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The wiring of the nervous system is established through a progressive refinement of the choices made by a growing axon. The growth cone is a highly motile structure at the tip of the axon that integrates the multitude of signals present in its environment and translates these signals into structural changes of the cytoskeleton that determine the rate and direction of extension. Four families of guidance cues were identified that provide directional information to growing axons: the ephrins, the netrins, the slit proteins, and the semaphorins. The semaphorins represent the largest family of guidance cues identified so far that can be divided into 8 classes based on the degree of sequence similarity between their semaphorin domains and the presence of class specific carboxy-terminal domains (CTD). Collectively, the in vitro data indicate that semaphorins function mainly as chemorepellents that direct axons away from tissues marked by their expression, but can also act as chemoattractants in some cases. Genetic analysis of the semaphorins and their receptor showed that these proteins play an important role in the development and function of different tissues other than the nervous system. The effects of the different semaphorins are mediated by a variety of receptor complexes that include members of the neuropilin and plexin protein families as well as other membrane proteins belonging to the immunoglobulin superfamily. Plexins directly and indirectly interact with members of the Rho-like GTPases, the kinases Fes, Fyn, and Cdk5, the oxidoreductase MICAL, lipoxygenase, and the CRMP proteins. The signal transduction cascades that include these signalling proteins and link semaphorin receptors to the cytoskeleton are still incompletely understood.
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Is Mical an oxidoreductase?
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the oxidoreductase MICAL
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In the last few weeks, the FDA approved three new therapies for multiple myeloma: ixazomib, the first oral proteasome inhibitor; and daratumumab and elotuzumab, two monoclonal antibodies that target CD38 and SLAMF7, respectively.
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What is the target of daratumumab?
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In the last few weeks, the FDA approved three new therapies for multiple myeloma: ixazomib, the first oral proteasome inhibitor; and daratumumab and elotuzumab, two monoclonal antibodies that target CD38 and SLAMF7, respectively.
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Miller Fisher syndrome is an acute inflammatory polyradiculoneuropathy that is generally considered a variant of Guillain-Barré syndrome and is characterized by the clinical triad of ataxia, areflexia, and ophthalmoplegia. Several reports of familial Guillain-Barré syndrome have been reported, indicating a possible underlying genetic and/or environmental predisposition to the development of Guillain-Barré syndrome. A familial association in Miller Fisher syndrome has not previously been described in the literature. We report 2 cases of Miller Fisher syndrome presenting simultaneously in siblings, with a review of recent relevant literature.
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Is the Miller-Fisher syndrome considered to be a variant of Guillain-Barré?
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Miller Fisher syndrome is an acute inflammatory polyradiculoneuropathy that is generally considered a variant of Guillain-Barré syndrome and is characterized by the clinical triad of ataxia,
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Primary neuronal cultures are a useful tool for measuring pharmacological- and transgene-regulated gene expression; however, accurate measurements can be confounded by heterogeneous cell types and inconsistent transfection efficiency. Here we describe our adaptation of a ribosomal capture strategy that was designed to be used in transgenic mice expressing tagged ribosomal subunits (RiboTag) in specific cell types, thereby allowing measurement of translating RNAs from desired cell types within complex tissues. Using this strategy we were able to isolate and analyze neuron-specific RNA despite the presence of glia by co-transfecting experimental plasmids with plasmids that selectively express RiboTag in neurons. RiboTag immunoprecipitation was capable of recovering high integrity RNA from small numbers of transfected cells that can then be interrogated by a variety of methods (e.g., RT-qPCR, PCR array, RNA-Seq) and compared with basal RNA expression of the entire culture. Additionally, we demonstrate how co-transfection of RiboTag with small hairpin RNA (shRNA) constructs can validate and accurately assess the degree of gene expression knockdown, and how RiboTag can be used to measure receptor-mediated gene regulation with transiently expressed designer receptors exclusively activated by designer drugs (DREADDs). RiboTag co-transfection represents a convenient and powerful tool to isolate RNA from a specific subset of cultured cells with a variety of applications for experiments in vitro.
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What is RiboTag profiling?
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Here we describe our adaptation of a ribosomal capture strategy that was designed to be used in transgenic mice expressing tagged ribosomal subunits (RiboTag) in specific cell types, thereby allowing measurement of translating RNAs from desired cell types within complex tissues. Using this strategy we were able to isolate and analyze neuron-specific RNA despite the presence of glia by co-transfecting experimental plasmids with plasmids that selectively express RiboTag in neurons. RiboTag immunoprecipitation was capable of recovering high integrity RNA from small numbers of transfected cells that can then be interrogated by a variety of methods (e.g., RT-qPCR, PCR array, RNA-Seq) and compared with basal RNA expression of the entire culture. Additionally, we demonstrate how co-transfection of RiboTag with small hairpin RNA (shRNA) constructs can validate and accurately assess the degree of gene expression knockdown, and how RiboTag can be used to measure receptor-mediated gene regulation with transiently expressed designer receptors exclusively activated by designer drugs (DREADDs). RiboTag co-transfection represents a convenient and powerful tool to isolate RNA from a specific subset of cultured cells with a variety of applications for experiments in vitro.
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Alcohol-based hand sanitizer is a liquid, gel, or foam that contains ethanol or isopropanol used to disinfect hands. Hand hygiene is an important component of the U.S. response to the emergence of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19). If soap and water are not readily available, CDC recommends the use of alcohol-based hand sanitizer products that contain at least 60% ethyl alcohol (ethanol) or 70% isopropyl alcohol (isopropanol) in community settings (1); in health care settings, CDC recommendations specify that alcohol-based hand sanitizer products should contain 60%-95% alcohol (≥60% ethanol or ≥70% isopropanol) (2). According to the Food and Drug Administration (FDA), which regulates alcohol-based hand sanitizers as an over-the-counter drug, methanol (methyl alcohol) is not an acceptable ingredient. Cases of ethanol toxicity following ingestion of alcohol-based hand sanitizer products have been reported in persons with alcohol use disorder (3,4). On June 30, 2020, CDC received notification from public health partners in Arizona and New Mexico of cases of methanol poisoning associated with ingestion of alcohol-based hand sanitizers. The case reports followed an FDA consumer alert issued on June 19, 2020, warning about specific hand sanitizers that contain methanol. Whereas early clinical effects of methanol and ethanol poisoning are similar (e.g., headache, blurred vision, nausea, vomiting, abdominal pain, loss of coordination, and decreased level of consciousness), persons with methanol poisoning might develop severe anion-gap metabolic acidosis, seizures, and blindness. If left untreated methanol poisoning can be fatal (5). Survivors of methanol poisoning might have permanent visual impairment, including complete vision loss; data suggest that vision loss results from the direct toxic effect of formate, a toxic anion metabolite of methanol, on the optic nerve (6). CDC and state partners established a case definition of alcohol-based hand sanitizer-associated methanol poisoning and reviewed 62 poison center call records from May 1 through June 30, 2020, to characterize reported cases. Medical records were reviewed to abstract details missing from poison center call records. During this period, 15 adult patients met the case definition, including persons who were American Indian/Alaska Native (AI/AN). All had ingested an alcohol-based hand sanitizer and were subsequently admitted to a hospital. Four patients died and three were discharged with vision impairment. Persons should never ingest alcohol-based hand sanitizer, avoid use of specific imported products found to contain methanol, and continue to monitor FDA guidance (7). Clinicians should maintain a high index of suspicion for methanol poisoning when evaluating adult or pediatric patients with reported swallowing of an alcohol-based hand sanitizer product or with symptoms, signs, and laboratory findings (e.g., elevated anion-gap metabolic acidosis) compatible with methanol poisoning. Treatment of methanol poisoning includes supportive care, correction of acidosis, administration of an alcohol dehydrogenase inhibitor (e.g., fomepizole), and frequently, hemodialysis.
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What is the active ingredient in the most common hand sanitizer?
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Clinicians should maintain a high index of suspicion for methanol poisoning when evaluating adult or pediatric patients with reported swallowing of an alcohol-based hand sanitizer product or with symptoms, signs, and laboratory findings (e.g., elevated anion-gap metabolic acidosis) compatible with methanol poisoning.
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Weevils (Curculionoidea) comprise one of the most diverse groups of organisms on earth. There is hardly a vascular plant or plant part without its own species of weevil feeding on it and weevil species diversity is greater than the number of fishes, birds, reptiles, amphibians and mammals combined. Here, we employ ultraconserved elements (UCEs) designed for beetles and a novel partitioning strategy of loci to help resolve phylogenetic relationships within the radiation of Australasian smurf-weevils (Eupholini). Despite being emblematic of the New Guinea fauna, no previous phylogenetic studies have been conducted on the Eupholini. In addition to a comprehensive collection of fresh specimens, we supplement our taxon sampling with museum specimens, and this study is the first target enrichment phylogenomic dataset incorporating beetle specimens from museum collections. We use both concatenated and species tree analyses to examine the relationships and taxonomy of this group. For species tree analyses we present a novel partitioning strategy to better model the molecular evolutionary process in UCEs. We found that the current taxonomy is problematic, largely grouping species on the basis of similar color patterns. Finally, our results show that most loci required multiple partitions for nucleotide rate substitution, suggesting that single partitions may not be the optimal partitioning strategy to accommodate rate heterogeneity for UCE loci.
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What is the contribution of ultraconserved elements in Australasian smurf-weevils?
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Here, we employ ultraconserved elements (UCEs) designed for beetles and a novel partitioning strategy of loci to help resolve phylogenetic relationships within the radiation of Australasian smurf-weevils (Eupholini). Despite being emblematic of the New Guinea fauna, no previous phylogenetic studies have been conducted on the Eupholini. In addition to a comprehensive collection of fresh specimens, we supplement our taxon sampling with museum specimens, and this study is the first target enrichment phylogenomic dataset incorporating beetle specimens from museum collections. We use both concatenated and species tree analyses to examine the relationships and taxonomy of this group. For species tree analyses we present a novel partitioning strategy to better model the molecular evolutionary process in UCEs. We found that the current taxonomy is problematic, largely grouping species on the basis of similar color patterns. Finally, our results show that most loci required multiple partitions for nucleotide rate substitution, suggesting that single partitions may not be the optimal partitioning strategy to accommodate rate heterogeneity for UCE loci.
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A quantitative trait locus (QTL) affecting milk fat percentage has been mapped to the centromeric end of the bovine chromosome 14 (BTA14). This genomic area includes the DGAT1 gene, which encodes acyl-CoA:diacylglycerol acyltransferase 1, the key enzyme of triglyceride biosynthesis. Genetic and biochemical studies led to the identification of the nonconservative DGAT1-K232A polymorphism as a causal mutation for the QTL. In addition to this, another polymorphism in the 5'-regulatory region of this gene, the DGAT1 variable number of tandem repeat (VNTR), also showed a strong association with milk fat percentage. This promoter VNTR polymorphism affects the number of potential Sp1 binding sites and therefore might have an impact on DGAT1 expression and also milk fat content. Hence, the DGAT1 VNTR polymorphism might be another causal mutation for the BTA14 QTL. However, evidence for Sp1 binding to this polymorphic site and for the capability of DGAT1 VNTR alleles to stimulate gene expression was lacking. In the current work Sp1-VNTR interactions were analyzed by EMSA. In addition, effects of DGAT1 VNTR alleles on gene expression were measured with reporter gene analyses. Conclusions from the results are that 1) the DGAT1 VNTR sequence is indeed a target for Sp1 binding; 2) DGAT1 VNTR alleles can stimulate gene expression in vitro and probably in vivo as well; and 3) although the stimulating effects of the different DGAT1 VNTR alleles did not show significant differences in vitro, their effects on transcription might be different in the chromatin context existing in vivo.
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What is the function of the DGAT1 gene product?
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This genomic area includes the DGAT1 gene, which encodes acyl-CoA:diacylglycerol acyltransferase 1, the key enzyme of triglyceride biosynthesis.
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The optimal surgical procedure for patients with calcified and organized chronic subdural haematoma (CSDH), or "armoured brain", has not been established because it is difficult to obtain good re-expansion of the brain after surgery. We present herein the case of a 32-year-old woman with huge calcified CSDH manifesting as refractory headache, periods of unconsciousness, and unsteady gait who obtained favourable results after craniotomy. Thinning of the thick calcified inner membrane using high-speed air drilling was performed after removal of the organized CSDH. The patient obtained good re-expansion after surgery. This observation illustrates that it is possible to perform such a surgery even on a huge calcified CSDH.
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Describe armoured brain syndrome.
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The optimal surgical procedure for patients with calcified and organized chronic subdural haematoma (CSDH), or "armoured brain", has not been established because it is difficult to obtain good re-expansion of the brain after surgery
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In the nucleus HuR binds to mRNAs containing adenylate-uridylate rich elements in the 3'-untranslated region. HuR may influence expression of its ligand mRNA through regulation of polyadenylation, translocation of the message to the cytosol, stabilization of the mRNA and/or altering its translational efficiency. Suppression of HuR using siRNA resulted in an attenuation of the 3T3-L1 differentiation program, consistent with HuR control of the expression of mRNA ligand(s) critical to the differentiation process. In the present study, we begin to identify mRNA ligands of HuR whose regulated expression is necessary for adipogenesis.
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Which are the main functions of the human HuR (ELAVL1) protein in fibroblasts?
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Suppression of HuR using siRNA resulted in an attenuation of the 3T3-L1 differentiation program, consistent with HuR control of the expression of mRNA ligand(s) critical to the differentiation process.
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Transcription-coupled DNA repair is a mechanism by which bulky DNA lesions that block transcription by RNA polymerase are prioritised for removal by the nucleotide excision repair apparatus. The trigger is thought to be the presence of an irreversibly blocked transcription complex, which is recognised by a transcription-repair coupling factor. Many common DNA lesions do not block transcription, but are bypassed with varying degrees of efficiency and with potentially mutagenic effects on the RNA transcripts that are produced. The effect of the bacterial transcription-repair coupling factor, Mfd, at such lesions is not known: it has been suggested that Mfd may promote mutagenesis by increasing the efficiency with which RNA polymerase bypasses non-bulky lesions, but it has also been reported that 8-oxoguanine, a major product of oxidative DNA damage that is efficiently bypassed by RNA polymerase, is subject to Mfd-dependent transcription-coupled repair in Escherichia coli. We have investigated the effect of Mfd during transcription of templates containing 8-oxoguanine, and various other non-bulky lesions. We show that an 8-oxoguanine in the template strand induces a transient pause in transcription, and that Mfd neither increases nor decreases the efficiency with which RNA polymerase bypasses the lesion. We also show that Mfd can displace a transcription complex stalled at a single strand nick, and that it decreases the efficiency with which RNA polymerase bypasses an abasic site. These activities are not affected by transcription rate, as similar results were obtained using "fast" and "slow" mutant RNA polymerases. Our findings suggest that 8-oxoguanine is unlikely to be directly targeted by the transcription-coupled repair pathway, and identify a potential role for Mfd in reducing the level of transcriptional mutagenesis caused by abasic sites.
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Which proteins act as factors that promote transcription-coupled repair in bacteria?
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The effect of the bacterial transcription-repair coupling factor, Mfd, at such lesions is not known: it has been suggested that Mfd may promote mutagenesis by increasing the efficiency with which RNA polymerase bypasses non-bulky lesions, but it has also been reported that 8-oxoguanine, a major product of oxidative DNA damage that is efficiently bypassed by RNA polymerase, is subject to Mfd-dependent transcription-coupled repair in Escherichia coli.
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Mutations in genes known to be responsible for most of the recognizable syndromes associated with bilateral coronal synostosis can be detected by molecular testing. The genetic alterations that could cause unilateral coronal synostosis are more elusive. It is recognized that FGFR and TWIST mutations can give rise to either bilateral or unilateral coronal synostosis, even in the same family. The authors undertook a prospective study of patients presenting with synostotic frontal plagiocephaly (unilateral coronal synostosis) to Children's Hospital Boston during the period from 1997 to 2000. Mutational analysis was performed on all patients and on selected parents whenever familial transmission was suspected. Intraoperative anthropometry was used in an effort to differentiate those patients in whom a mutation was detected from those in whom it was not. The anthropometric measures included bilateral sagittal orbital-globe distance, inter medial canthal distance, and nasal angulation. Macrocephaly and palpebral angulation were also considered possible determinants. There was a 2:1 female preponderance in 47 patients with synostotic frontal plagiocephaly. Mutations were found in eight of 47 patients: two patients with different single-amino-acid changes in FGFR2, three patients with FGFR3 Pro250Arg, and three patients with TWIST mutations. Another patient had craniofrontonasal syndrome for which a causative locus has been mapped to chromosome X, although molecular testing is not yet available. Two features were strongly associated with a detectable mutation in patients with synostotic frontal plagiocephaly: asymmetrical brachycephaly (retrusion of both supraorbital rims) and orbital hypertelorism. Other abnormalities in the craniofacial region and extremities were clues to a particular mutation in FGFR2, FGFR3, TWIST, or the X-linked mutation. Neither macrocephaly nor degree of nasal angulation nor relative vertical position of the lateral canthi correlated with mutational detection. An additional four patients in this study had either unilateral or bilateral coronal synostosis in an immediate relative and had anthropometric findings that predicted a mutation, and yet no genetic alteration was found. This suggests either that the authors' screening methods were not sufficiently sensitive or that perhaps there are other unknown pathogenic loci. Nevertheless, molecular testing is recommended for infants who have unilateral coronal synostosis, particularly if there are the anthropometric findings highlighted in this study or an otherwise suspicious feature in the child or a parent. Infants with either an identified or a suspected mutation usually need bilateral asymmetric advancement of the bandeau and may be more likely to require frontal revision in childhood.
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Is there an association between FGFR3 mutation and plagiocephaly?
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Other abnormalities in the craniofacial region and extremities were clues to a particular mutation in FGFR2, FGFR3, TWIST, or the X-linked mutation.
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The production performance of pigs has been significantly improved due to long-term artificial selection, and the specific variation characterizations (selection signatures) emerged from the selected genome regions. Different types of breeds are subjected to different selection intensities and had different selection signatures. Selective sweep analysis is one of major methods to detect the selection signatures. In this study, based on the 60K BeadChip genotyping data of both commercial Large White (n=45) and local Tongcheng pigs (n=45), genetic differentiation coefficient Fst was applied to detect the selection signatures. Using gPLINK software to set quality control standards, a total of 34 304 SNPs were selected for statistical analysis. Fst values between two breeds were estimated with Genepop package and the average Fst value was 0.3209. Setting Fst>0.7036 (1% of total number of Fst values) as selection threshold, 344 SNPs were obtained and SNP location annotation indicated that there were 79 candidate genes (Sus scrofa Build 9). Furthermore, network analysis was performed using Ingenuity Pathway Analysis and the preliminary results suggested that most genes were involved in growth, reproduction, and immune response, such as NCOA6, ERBB4, RUNX2, and APOB genes. The findings from this study will contribute to further identification of candidate genes and causal mutations implying for meat production and disease resistance in pig.
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Which software are used for the detection of selective sweeps?
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Using gPLINK software to set quality control standards, a total of 34 304 SNPs were selected for statistical analysis. Fst values between two breeds were estimated with Genepop package and the average Fst value was 0.3209.
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Recent studies have disclosed the function of enhancer RNAs (eRNAs), which are long non-coding RNAs transcribed from gene enhancer regions, in transcriptional regulation. However, it remains unclear whether eRNAs are involved in the regulation of human heme oxygenase-1 gene (HO-1) induction. Here, we report that multiple nuclear-enriched eRNAs are transcribed from the regions adjacent to two human HO-1 enhancers (i.e. the distal E2 and proximal E1 enhancers), and some of these eRNAs are induced by the oxidative stress-causing reagent diethyl maleate (DEM). We demonstrated that the expression of one forward direction (5' to 3') eRNA transcribed from the human HO-1 E2 enhancer region (named human HO-1enhancer RNA E2-3; hereafter called eRNA E2-3) was induced by DEM in an NRF2-dependent manner in HeLa cells. Conversely, knockdown of BACH1, a repressor of HO-1 transcription, further increased DEM-inducible eRNA E2-3 transcription as well as HO-1 expression. In addition, we showed that knockdown of eRNA E2-3 selectively down-regulated DEM-induced HO-1 expression. Furthermore, eRNA E2-3 knockdown attenuated DEM-induced Pol II binding to the promoter and E2 enhancer regions of HO-1 without affecting NRF2 recruitment to the E2 enhancer. These findings indicate that eRNAE2-3 is functional and is required for HO-1 induction.
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Are there enhancer RNAs (eRNAs)?
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Recent studies have disclosed the function of enhancer RNAs (eRNAs), which are long non-coding RNAs transcribed from gene enhancer regions, in transcriptional regulation.
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The prevalence of metabolic disorders (MDs), especially diabetes, is rapidly increasing worldwide, leading to an increasing risk of cardiovascular and other socially relevant complications. To boost MD biomarker discovery, advanced proteomics can harmonize metabolomics. Indeed, the rapid development of mass spectrometry (MS) has designated proteomics as an emerging platform to interrogate the plasma/serum proteome for the discovery of next-generation biomarkers exploitable for risk assessment, early detection and prognosis of MDs. Preanalytical plasma/serum treatment, such as combinatorial peptide ligand libraries with nano-liquid chromatography coupled with tandem MS or selected reaction monitoring coupled to triple-quadrupole time-of-flight instruments, are proven clinical laboratory techniques for quantitative analyses. New strategies, such as SWATH™ MS, which allows us to systematically characterize and quantify query sample sets of 'any protein of interest' in complex biological samples, may dramatically improve next-generation MD biomarkers, especially considering the plethora of candidates coming from the 'bioreactor' gut microbiota affecting MD onset and progression.
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What is the main application of SWATH-MS in proteomics?
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ew strategies, such as SWATH™ MS, which allows us to systematically characterize and quantify query sample sets of 'any protein of interest' in complex biological samples,
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Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder; however, it remains underdiagnosed and undertreated. Although screening tools such as the Berlin questionnaire (BQ), STOP-BANG questionnaire (SBQ), STOP questionnaire (STOP), and Epworth sleepiness scale (ESS) are widely used for OSA, the findings regarding their diagnostic accuracy are controversial. Therefore, this meta-analysis investigated and compared the summary sensitivity, specificity, and diagnostic odds ratio (DOR) among the BQ, SBQ, STOP, and ESS according to the severity of OSA. Electronic databases, namely the Embase, PubMed, PsycINFO, ProQuest dissertations and theses A&I databases, and China knowledge resource integrated database, were searched from their inception to July 15, 2016. We included studies examining the sensitivity and specificity of the BQ, SBQ, STOP, and ESS against the apnea-hypopnea index (AHI) or respiratory disturbance index (RDI). The revised quality assessment of diagnostic accuracy studies was used to evaluate the methodological quality of studies. A random-effects bivariate model was used to estimate the summary sensitivity, specificity, and DOR of the tools. We identified 108 studies including a total of 47 989 participants. The summary estimates were calculated for the BQ, SBQ, STOP, and ESS in detecting mild (AHI/RDI ≥ 5 events/h), moderate (AHI/RDI ≥ 15 events/h), and severe OSA (AHI/RDI ≥ 30 events/h). The performance levels of the BQ, SBQ, STOP, and ESS in detecting OSA of various severity levels are outlined as follows: for mild OSA, the pooled sensitivity levels were 76%, 88%, 87%, and 54%; pooled specificity levels were 59%, 42%, 42%, and 65%; and pooled DORs were 4.30, 5.13, 4.85, and 2.18, respectively. For moderate OSA, the pooled sensitivity levels were 77%, 90%, 89%, and 47%; pooled specificity levels were 44%, 36%, 32%, and 621%; and pooled DORs were 2.68, 5.05, 3.71, and 1.45, respectively. For severe OSA, the pooled sensitivity levels were 84%, 93%, 90%, and 58%; pooled specificity levels were 38%, 35%, 28%, and 60%; and pooled DORs were 3.10, 6.51, 3.37, and 2.10, respectively. Therefore, for mild, moderate, and severe OSA, the pooled sensitivity and DOR of the SBQ were significantly higher than those of other screening tools (P < .05); however, the specificity of the SBQ was lower than that of the ESS (P < .05). Moreover, age, sex, body mass index, study sample size, study populations, presence of comorbidities, PSG or portable monitoring performance, and risk of bias in the domains of the index test and reference standard were significant moderators of sensitivity and specificity (P < .05). Compared with the BQ, STOP, and ESS, the SBQ is a more accurate tool for detecting mild, moderate, and severe OSA. Sleep specialists should use the SBQ to conduct patient interviews for the early diagnosis of OSA in clinical settings, particularly in resource-poor countries and sleep clinics where PSG is unavailable.
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Which disease risk can be estimated with the Stop-Bang questionnaire?
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Compared with the BQ, STOP, and ESS, the SBQ is a more accurate tool for detecting mild, moderate, and severe OSA. Sleep specialists should use the SBQ to conduct patient interviews for the early diagnosis of OSA in clinical settings, particularly in resource-poor countries and sleep clinics where PSG is unavailable.
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Diabetes induces cardiomyocyte apoptosis and suppresses cardiac autophagy, indicating that the interplay between autophagy and apoptotic cell death pathways is important in the pathogenesis of diabetic cardiomyopathy. The potential mechanism, however, remains unknown. We recently reported that diabetes depresses AMP-activated protein kinase (AMPK) activity, inhibits MAPK8/JNK1-BCL2 signaling, and promotes the interaction between BECN1 and BCL2. Concomitantly, diabetes induces cardiomyocyte apoptosis and suppresses cardiac autophagy. Activation of AMPK directly phosphorylates MAPK8, which mediates BCL2 phosphorylation and subsequent BECN1-BCL2 dissociation, leading to restoration of cardiac autophagy, protection against cardiac apoptosis, and ultimately improvement in cardiac structure and function. We conclude that dissociation of BCL2 from BECN1 through activation of MAPK8-BCL2 signaling may be an important mechanism by which AMPK activation restores autophagy, protects against cardiac apoptosis, and prevents diabetic cardiomyopathy.
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What is the role of AMPK in diabetic cardiomyopathy?
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Activation of AMPK directly phosphorylates MAPK8, which mediates BCL2 phosphorylation and subsequent BECN1-BCL2 dissociation, leading to restoration of cardiac autophagy, protection against cardiac apoptosis, and ultimately improvement in cardiac structure and function.
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In an animal model of AMI relevant to the human disease, intracoronary administration of IGF-1/HGF is a practical and effective strategy to reduce pathological cardiac remodeling, induce myocardial regeneration, and improve ventricular function.
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what is the role of IGF-1 in cardiac regeneration after myocardial infarction?
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In an animal model of AMI relevant to the human disease, intracoronary administration of IGF-1/HGF is a practical and effective strategy to reduce pathological cardiac remodeling, induce myocardial regeneration, and improve ventricular function.
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Ivosidenib (Tibsovo) is a small molecule, orally available inhibitor of mutated cytosolic isocitrate dehydrogenase 1 (IDH1) that is being developed by Agios Pharmaceuticals for the treatment of cancer in patients with IDH1 mutations. The mutated form of the IDH1 enzyme produces a metabolite, 2-hydroxyglutarate (2-HG), which is thought to play a role in the formation and progression of acute myeloid leukaemia (AML), gliomas and other cancers. Elevated 2-HG levels interfere with cellular metabolism and epigenetic regulation, thereby contributing to oncogenesis. Ivosidenib targets the IDH1 metabolic pathway to prevent a build-up of the oncometabolite 2-HG. This article summarizes the milestones in the development of ivosidenib leading to this first approval in the USA for the treatment of patients with relapsed or refractory AML with a susceptible IDH1 mutation. Clinical development for AML, cholangiocarcinoma, glioma, myelodysplastic syndromes and solid tumours is ongoing worldwide.
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Which molecule is inhibited by ivosidenib?
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Ivosidenib targets the IDH1 metabolic pathway to prevent a build-up of the oncometabolite 2-HG.
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Background We evaluated the effect of erenumab, a fully human monoclonal antibody that inhibits the canonical calcitonin gene-related peptide receptor, on migraine-related disability, impact, and health-related quality of life among patients with episodic migraine. Methods Patients enrolled in a phase 3, 6-month, double-blind, placebo-controlled study of once-monthly erenumab 70 and 140 mg for migraine prevention (STRIVE) used an eDiary during the baseline and double-blind treatment phases to complete validated, specific questionnaires, including the modified (monthly) Migraine Disability Assessment Questionnaire; Headache Impact Test; and Migraine-Specific Quality of Life Questionnaire-role function-restrictive (MSQ-RFR), -role function-preventive (MSQ-RFP), and -emotional function (MSQ-EF). Results A total of 955 patients were randomized to receive erenumab 70 mg (n = 317), erenumab 140 mg (n = 319), or placebo (n = 319). Erenumab versus placebo resulted in significantly greater improvements in all patient-reported outcomes; changes from baseline were numerically higher with 140 mg erenumab. Improvements occurred rapidly and were maintained over 6 months of treatment. Between-group differences from placebo over months 4-6 for the 70- and 140-mg dose groups were, respectively, -2.1 and -2.8 for modified (monthly) Migraine Disability Assessment Questionnaire, -2.1 and -2.3 for Headache Impact Test, 5.1 and 6.5 for MSQ-RFR, 4.2 and 5.4 for MSQ-RFP, and 5.2 and 6.7 for MSQ-EF ( p < 0.001 for all). Erenumab also significantly reduced the proportion of patients with severe and very severe migraine-related disability and increased the proportion of patients with clinically meaningful improvements in migraine-related impact and health-related quality of life. Conclusion Erenumab reduced migraine disability and impact and improved patients' health-related quality of life, reinforcing its role as a promising new therapy for migraine prevention.
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Which receptor is targeted by Erenumab?
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Background We evaluated the effect of erenumab, a fully human monoclonal antibody that inhibits the canonical calcitonin gene-related peptide receptor, on migraine-related disability, impact, and health-related quality of life among patients with episodic migraine.
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CENP-A is a centromere-specific histone H3 variant that is required for kinetochore assembly and accurate chromosome segregation. For it to function properly, CENP-A must be specifically localized to centromeres. In fission yeast, Scm3sp and the Mis18 complex, composed of Mis16, Eic1, and Mis18, function as a CENP-A(Cnp1)-specific chaperone and a recruiting factor, respectively, and together ensure accurate delivery of CENP-A(Cnp1) to centromeres. Although how Scm3sp specifically recognizes CENP-A(Cnp1) has been revealed recently, the recruiting mechanism of CENP-A(Cnp1) via the Mis18 complex remains unknown. In this study, we have determined crystal structures of Schizosaccharomyces japonicus Mis16 alone and in complex with the helix 1 of histone H4 (H4α1). Crystal structures followed by mutant analysis and affinity pull-downs have revealed that Mis16 recognizes both H4α1 and Scm3sp independently within the CENP-A(Cnp1)/H4:Scm3sp complex. This observation suggests that Mis16 gains CENP-A(Cnp1) specificity by recognizing both Scm3sp and histone H4. Our studies provide insights into the molecular mechanisms underlying specific recruitment of CENP-A(Cnp1)/H4:Scm3sp into centromeres.
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What is the function of the Mis18 protein?
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In fission yeast, Scm3sp and the Mis18 complex, composed of Mis16, Eic1, and Mis18, function as a CENP-A(Cnp1)-specific chaperone and a recruiting factor, respectively, and together ensure accurate delivery of CENP-A(Cnp1) to centromeres.
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Metabotropic glutamate receptor 5 (mGluR5) has been implicated in Alzheimer's disease (AD) pathology. We sought to understand whether mGluR5's role in AD requires glutamate signaling. We used a potent mGluR5 silent allosteric modulator (SAM, BMS-984923) to separate its well-known physiological role in glutamate signaling from a pathological role in mediating amyloid-β oligomer (Aβo) action. Binding of the SAM to mGluR5 does not change glutamate signaling but strongly reduces mGluR5 interaction with cellular prion protein (PrP) bound to Aβo. The SAM compound prevents Aβo-induced signal transduction in brain slices and in an AD transgenic mouse model, the APPswe/PS1ΔE9 strain. Critically, 4 weeks of SAM treatment rescues memory deficits and synaptic depletion in the APPswe/PS1ΔE9 transgenic mouse brain. Our data show that mGluR5's role in Aβo-dependent AD phenotypes is separate from its role in glutamate signaling and silent allosteric modulation of mGluR5 has promise as a disease-modifying AD intervention with a broad therapeutic window.
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Silent Allosteric Modulation of mGluR5 is a form of treatment for what disease?
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silent allosteric modulation of mGluR5 has promise as a disease-modifying AD intervention with a broad therapeutic window.
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Monoamine Oxidase A (MAOA) is a critical enzyme in the catabolism of monoaminergic neurotransmitters. MAOA transcriptional activity is thought to be regulated by a well characterized 30 base pair (bp) variable nucleotide repeat (VNTR) that lies approximately ∼1000 bp upstream of the transcriptional start site (TSS). However, clinical associations between this VNTR genotype and behavioral states have been inconsistent. Herein, we describe a second, 10 bp VNTR that lies ∼1500 bp upstream of the TSS. We provide in vitro and in silico evidence that this new VNTR region may be more influential in regulating MAOA transcription than the more proximal VNTR and that methylation of this CpG-rich VNTR is genotype dependent in females. Finally, we demonstrate that genotype at this new VNTR interacts significantly with history of child abuse to predict antisocial personality disorder (ASPD) in women and accounts for variance in addition to that explained by the prior VNTR.
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With which personality traits has the human monoamine oxidase A (MAOA) gene been associated?
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However, clinical associations between this VNTR genotype and behavioral states have been inconsistent.
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A recently described protein, metaxin 1, serves as a component of a preprotein import complex in the outer membrane of the mammalian mitochondrion. A yeast two-hybrid screen with metaxin 1 as bait has now identified a novel protein, which we have termed metaxin 2, as a metaxin 1-binding protein. Metaxin 2 shares 29% identity with metaxin 1 at the amino acid level, but metaxin 2, unlike metaxin 1, lacks a C-terminal mitochondrial outer membrane signal-anchor domain. Two C. elegans hypothetical proteins, CelZC97.1 and CelF39B2.i, share high sequence similarity with metaxin 2 and metaxin 1, respectively, and likely represent the C. elegans orthologs. Affinity-purified antibodies against metaxin 2 were prepared against the recombinant protein produced in E. coli and were used to analyze the subcellular distribution of metaxin 2. In subcellular fractions of mouse liver, a 29 kD immunoreactive protein, consistent in size with the predicted translation product of metaxin 2 cDNA, was found solely in mitochondria. Alkali extraction of mitochondria indicated that metaxin 2 is peripherally associated with mitochondrial membranes. Metaxin 2 in intact mitochondria was susceptible to digestion with proteinase K, indicating that metaxin 2 is located on the cytosolic face of the mitochondrial outer membrane. Finally, baculoviruses encoding a His6-tagged metaxin 2 and an untagged metaxin 1 lacking its C-terminal transmembrane domain were produced and used separately or in combination to infect Sf21 insect cells. Metaxin 1 bound to a Ni2+-chelate affinity column only in the presence of metaxin 2, indicating that metaxin 1 and metaxin 2 interact when overexpressed in insect cells. These results suggest that metaxin 2 is bound to the cytosolic face of the mitochondrial outer membrane by means of its interaction with membrane-bound metaxin 1, and that this complex may play a role in protein import into mammalian mitochondria.
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Where is the metaxin complex localized?
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In subcellular fractions of mouse liver, a 29 kD immunoreactive protein, consistent in size with the predicted translation product of metaxin 2 cDNA, was found solely in mitochondria.
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Acute akinesia is a life-threatening complication of Parkinson disease (PD). It is unlike the "wearing-off" phenomenon that occurs when dopaminergic drug levels decline and responds to dopaminergic rescue drugs. Acute akinesia may be a clinical entity distinct from the previously described PD motor fluctuations.
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What is the "wearing-off" phenomenon in levodopa-treated patients with Parkinson's Disease?
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It is unlike the "wearing-off" phenomenon that occurs when dopaminergic drug levels decline and responds to dopaminergic rescue drugs.
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No standard chemotherapy regimens have been defined yet for extranodal natural killer/T cell lymphoma (ENKTL), and the prognosis of patients with advanced or relapsed disease is very poor. Daratumumab, an investigated anti-cancer drug targeting CD38, has been of great interest in the treatment of CD38-expressing malignancies, especially multiple myeloma. In this study, we reviewed the clinical data of 94 patients with ENKTL, investigated the expression of CD38, and analyzed the prognostic value of CD38 expression. Forty-seven patients had weak expression of CD38, and the other 47 patients had strong expression. The complete response (CR) rate was significantly higher in patients who were treated with asparaginase-based therapy (83.8 vs. 59.6 %, p = 0.025). There was a trend towards higher CR rate in CD38 weak expression group (78.7 vs. 59.6 %, p = 0.074). At a median follow-up time of 42 months, the 2-year and 5-year progression-free survival (PFS) rates were 53.0 and 39.0 %, respectively, and the 2-year and 5-year overall survival (OS) rates were 68.0 and 58.0 %, respectively. In multivariate survival analysis including CD38 expression status, International Prognostic Index (IPI) score, local tumor invasion, and chemotherapy regimens, it was found that strong expression of CD38 and non-asparaginase-based chemoregimens were independent adverse prognostic factors for PFS (p = 0.009 and 0.027, respectively), while local tumor invasion and higher IPI score were independent adverse prognostic factors for OS (p = 0.002 and 0.035, respectively). In subgroup analysis, strong expression of CD38 significantly correlated with inferior survival outcomes in patients without local tumor invasion (p = 0.011) or with stage I-II disease (p = 0.008). In conclusion, we firstly found that the majority of ENKTL cases were CD38 positive, with half had strong expression of CD38, which significantly correlated with poor outcomes, indicating the potential role of CD38 as a therapy target for ENKTL.
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Which molecule is targeted by Daratumumab?
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Daratumumab, an investigated anti-cancer drug targeting CD38, has been of great interest in the treatment of CD38-expressing malignancies, especially multiple myeloma.
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C3G (Crk SH3 domain binding guanine nucleotide releasing factor) (Rap guanine nucleotide exchange factor 1), essential for mammalian embryonic development, is ubiquitously expressed and undergoes regulated nucleocytoplasmic exchange. Here we show that C3G localizes to SC35-positive nuclear speckles and regulates splicing activity. Reversible association of C3G with speckles was seen on inhibition of transcription and splicing. C3G shows partial colocalization with SC35 and is recruited to a chromatin and RNase-sensitive fraction of speckles. Its presence in speckles is dependent on intact cellular actin cytoskeleton and is lost on expression of the kinase Clk1. Rap1, a substrate of C3G, is also present in nuclear speckles, and inactivation of Rap signaling by expression of GFP-Rap1GAP alters speckle morphology and number. Enhanced association of C3G with speckles is seen on glycogen synthase kinase 3 beta inhibition or differentiation of C2C12 cells to myotubes. CRISPR/Cas9-mediated knockdown of C3G resulted in altered splicing activity of an artificial gene as well as endogenous CD44. C3G knockout clones of C2C12 as well as MDA-MB-231 cells showed reduced protein levels of several splicing factors compared with control cells. Our results identify C3G and Rap1 as novel components of nuclear speckles and a role for C3G in regulating cellular RNA splicing activity.
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Which biological process takes place in nuclear speckles?
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Here we show that C3G localizes to SC35-positive nuclear speckles and regulates splicing activity.
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Progranulin, a secreted glycoprotein, is encoded in humans by the single GRN gene. Progranulin consists of seven and a half, tandemly repeated, non-identical copies of the 12 cysteine granulin motif. Many cellular processes and diseases are associated with this unique pleiotropic factor that include, but are not limited to, embryogenesis, tumorigenesis, inflammation, wound repair, neurodegeneration and lysosome function. Haploinsufficiency caused by autosomal dominant mutations within the GRN gene leads to frontotemporal lobar degeneration, a progressive neuronal atrophy that presents in patients as frontotemporal dementia. Frontotemporal dementia is an early onset form of dementia, distinct from Alzheimer's disease. The GRN-related form of frontotemporal lobar dementia is a proteinopathy characterized by the appearance of neuronal inclusions containing ubiquitinated and fragmented TDP-43 (encoded by TARDBP). The neurotrophic and neuro-immunomodulatory properties of progranulin have recently been reported but are still not well understood. Gene delivery of GRN in experimental models of Alzheimer's- and Parkinson's-like diseases inhibits phenotype progression. Here we review what is currently known concerning the molecular function and mechanism of action of progranulin in normal physiological and pathophysiological conditions in both in vitro and in vivo models. The potential therapeutic applications of progranulin in treating neurodegenerative diseases are highlighted.
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What protein is encoded by the GRN gene?
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Progranulin, a secreted glycoprotein, is encoded in humans by the single GRN gene.
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Mammalian interphase chromosomes fold into a multitude of loops to fit the confines of cell nuclei, and looping is tightly linked to regulated function. Chromosome conformation capture (3C) technology has significantly advanced our understanding of this structure-to-function relationship. However, all 3C-based methods rely on chemical cross-linking to stabilize spatial interactions. This step remains a "black box" as regards the biases it may introduce, and some discrepancies between microscopy and 3C studies have now been reported. To address these concerns, we developed "i3C", a novel approach for capturing spatial interactions without a need for cross-linking. We apply i3C to intact nuclei of living cells and exploit native forces that stabilize chromatin folding. Using different cell types and loci, computational modeling, and a methylation-based orthogonal validation method, "TALE-iD", we show that native interactions resemble cross-linked ones, but display improved signal-to-noise ratios and are more focal on regulatory elements and CTCF sites, while strictly abiding to topologically associating domain restrictions.
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What is the TALE-iD method used for?
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Using different cell types and loci, computational modeling, and a methylation-based orthogonal validation method, "TALE-iD", we show that native interactions resemble cross-linked ones, but display improved signal-to-noise ratios and are more focal on regulatory elements and CTCF sites, while strictly abiding to topologically associating domain restrictions.
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The large size of spectrin, the flexible protein promoting reversible deformation of red cells, has been an obstacle to elucidating the molecular mechanism of its function. By studying cloned fragments of the repeating unit domain, we have found a correspondence between positions of selected spectrin repeats in a tetramer with their stabilities of folding. Six fragments consisting of two spectrin repeats were selected for study primarily on the basis of the predicted secondary structures of their linker regions. Fragments with a putatively helical linker were more stable to urea- and heat-induced unfolding than those with a putatively nonhelical linker. Two of the less stably folded fragments, human erythroid alpha-spectrin repeats 13 and 14 (HEalpha13,14) and human erythroid beta-spectrin repeats 8 and 9 (HEbeta8,9), are located opposite each other on antiparallel spectrin dimers. At least partial unfolding of these repeats under physiological conditions indicates that they may serve as a hinge. Also less stably folded, the fragment of human erythroid alpha-spectrin repeats 4 and 5 (HEalpha4,5) lies opposite the site of interaction between the partial repeats at the C- and N-terminal ends of beta- and alpha-spectrin, respectively, on the opposing dimer. More stably folded fragments, human erythroid alpha-spectrin repeats 1 and 2 (HEalpha1,2) and human erythroid alpha-spectrin repeats 2 and 3 (HEalpha2,3), lie nearly opposite each other on antiparallel spectrin dimers of a tetramer. These clusterings along the spectrin tetramer of repeats with similar stabilities of folding may have relevance for spectrin function, particularly for its well known flexibility.
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Alpha-spectrin and beta-spectrin subunits form parallel or antiparallel heterodimers?
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Two of the less stably folded fragments, human erythroid alpha-spectrin repeats 13 and 14 (HEalpha13,14) and human erythroid beta-spectrin repeats 8 and 9 (HEbeta8,9), are located opposite each other on antiparallel spectrin dimers.
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We have determined the nucleotide sequence of the murine immunoglobulin gamma 2a membrane 3' untranslated region (1413 nucleotides) and approximately 679 nucleotides of downstream sequence. Two AATAAA hexanucleotide sequences are present in the 2092 nucleotide interval. The first one functions as the major polyA signal, directing cleavage and polyadenylation at a site 20 nucleotides downstream. Within 41 nucleotides downstream of the major membrane polyA signal are two sequences with 75% homology to the consensus sequence, (C/T)GTGTT(C/T)(C/T), identified by McLauchlan et al. [Nucl. Acids Res. 13, 1347-1365 (1985)]. An 80% homology match to the Berget consensus sequence, CA(C/T)TG, begins five nucleotides 3' of the major polyA site (used 20 times more than the second, downstream polyA site) [Berget Nature 309, 179-182 (1984)]. The second AATAAA, located 73 nucleotides 3' of the first, directs cleavage and polyadenylation 18 nucleotides downstream at a minor polyA site. One match with 75% homology to the McLauchlan consensus sequence begins 17 nucleotides 3' of the second (weaker) polyA site. No matches to the Berget consensus sequence are located near this second, weaker polyA site.
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What is the most prominent sequence consensus for the polyadenylation site?
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Two AATAAA hexanucleotide sequences are present in the 2092 nucleotide interval. The first one functions as the major polyA signal
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The anti programmed cell death-1 (PD-1) antibodies pembrolizumab and nivolumab have been recently licensed by the Food and Drug Administration for the treatment of advanced melanoma. Immune checkpoint inhibitors such as these can induce endocrine adverse events but autoimmune diabetes has not been described to date. However, there is a strong preclinical rationale that supports this autoimmune toxicity. We describe for the first time the case of an adult patient who developed autoimmune diabetes likely as a consequence of PD-1 inhibition with pembrolizumab. The presence of high serum titres of anti-glutamic acid decarboxylase antibodies together with a suggestive clinical presentation, age of the patient and preclinical data strongly support an autoimmune aetiology of the diabetes. Moreover, the patient was found to have a well-known high-risk human leucocyte antigen type for the development of type 1 diabetes in children, so the PD-1 inhibition is very likely to have triggered the autoimmune phenomenon. Our case suggests that insulin-dependent diabetes might be a rare but important anti-PD-1 immune-related adverse event.
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What is targeted by monoclonal antibody Pembrolizumab?
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We describe for the first time the case of an adult patient who developed autoimmune diabetes likely as a consequence of PD-1 inhibition with pembrolizumab.
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Drug interactions involving protease inhibitors are common. Protease inhibitors are well known inhibitors of the 3A4 isozyme of cytochrome P450. Select protease inhibitors, including co-formulated lopinavir/ritonavir, may induce glucuronidation or the activity of other CYP450 isozymes. We describe the case of a patient taking warfarin who experienced a significantly decreased international normalized ratio after the initiation of antiretroviral therapy that included lopinavir/ritonavir. We review the possible mechanisms of this interaction and the reported interactions between warfarin and other protease inhibitors.
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Please list 7 classes of drugs that interact with Warfarin.
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We review the possible mechanisms of this interaction and the reported interactions between warfarin and other protease inhibitors.
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Different classes of non-coding RNAs, including microRNAs, have recently been implicated in the process of tumourigenesis. In this study, we examined the expression and putative functions of a novel class of non-coding RNAs known as transcribed ultraconserved regions (T-UCRs) in neuroblastoma. Genome-wide expression profiling revealed correlations between specific T-UCR expression levels and important clinicogenetic parameters such as MYCN amplification status. A functional genomics approach based on the integration of multi-level transcriptome data was adapted to gain insights into T-UCR functions. Assignments of T-UCRs to cellular processes such as TP53 response, differentiation and proliferation were verified using various cellular model systems. For the first time, our results define a T-UCR expression landscape in neuroblastoma and suggest widespread T-UCR involvement in diverse cellular processes that are deregulated in the process of tumourigenesis.
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Are transcribed ultraconserved regions involved in cancer?
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Different classes of non-coding RNAs, including microRNAs, have recently been implicated in the process of tumourigenesis. In this study, we examined the expression and putative functions of a novel class of non-coding RNAs known as transcribed ultraconserved regions (T-UCRs) in neuroblastoma
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Biological systems are hierarchically self-organized complex structures characterized by nonlinear interactions. Biochemical energy is transformed into work of physical forces required for various biological functions. We postulate that energy transduction depends on endogenous electrodynamic fields generated by microtubules. Microtubules and mitochondria colocalize in cells with microtubules providing tracks for mitochondrial movement. Besides energy transformation, mitochondria form a spatially distributed proton charge layer and a resultant strong static electric field, which causes water ordering in the surrounding cytosol. These effects create conditions for generation of coherent electrodynamic field. The metabolic energy transduction pathways are strongly affected in cancers. Mitochondrial dysfunction in cancer cells (Warburg effect) or in fibroblasts associated with cancer cells (reverse Warburg effect) results in decreased or increased power of the generated electromagnetic field, respectively, and shifted and rebuilt frequency spectra. Disturbed electrodynamic interaction forces between cancer and healthy cells may favor local invasion and metastasis. A therapeutic strategy of targeting dysfunctional mitochondria for restoration of their physiological functions makes it possible to switch on the natural apoptotic pathway blocked in cancer transformed cells. Experience with dichloroacetate in cancer treatment and reestablishment of the healthy state may help in the development of novel effective drugs aimed at the mitochondrial function.
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Which is the primary distinction between the Reverse Warburg effect and the conventional Warburg effect?
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The metabolic energy transduction pathways are strongly affected in cancers. Mitochondrial dysfunction in cancer cells (Warburg effect) or in fibroblasts associated with cancer cells (reverse Warburg effect) results in decreased or increased power of the generated electromagnetic field, respectively
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Septins are an evolutionarily conserved family of GTP-binding proteins. They are involved in diverse processes including cytokinesis, apoptosis, infection, neurodegeneration and neoplasia. In this study, through thorough data mining of existed channel catfish genomic resources, we identified a complete set of 15 septin genes. Septins were classified into four subgroups according to phylogenetic analysis. Extensive comparative genomic analysis, including domain and syntenic analysis, supported their annotation and orthologies. The expression patterns of septins in channel catfish were examined in healthy tissues and after infection with two major bacterial pathogens, Edwardsiella ictaluri and Flavobacterium columnare. In healthy channel catfish, most septin genes were ubiquitously expressed and presented diversity patterns in various tissues, especially mucosal tissues, proposing the significant roles septin genes may play in maintaining homeostasis and host immune response activities. After bacterial infections, most septin genes were regulated, but opposite direction in expression profiles were found with the two bacterial pathogens: the differentially expressed septin genes were down-regulated in the intestine after E. ictaluri infection while generally up-regulated in the gill after F. columnare infection, suggesting a pathogen-specific and tissue-specific pattern of regulation. Taken together, these results suggested that septin genes may play complex and important roles in the host immune responses to bacterial pathogens in channel catfish.
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What are Septins?
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Septins are an evolutionarily conserved family of GTP-binding proteins. They are involved in diverse processes including cytokinesis, apoptosis, infection, neurodegeneration and neoplasia.
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Angiogenin (ANG) promotes cell growth and survival. Under growth conditions, ANG undergoes nuclear translocation and accumulates in the nucleolus where it stimulates rRNA transcription. When cells are stressed, ANG mediates the production of tRNA-derived stress-induced small RNA (tiRNA), which reprograms protein translation into a survival mechanism. The ribonucleolytic activity of ANG is essential for both processes but how this activity is regulated is unknown. We report here that ribonuclease/angiogenin inhibitor 1 (RNH1) controls both the localization and activity of ANG. Under growth conditions, ANG is located in the nucleus and is not associated with RNH1 so that the ribonucleolytic activity is retained to ensure rRNA transcription. Cytoplasmic ANG is associated with and inhibited by RNH1 so that random cleavage of cellular RNA is prevented. Under stress conditions, ANG is localized to the cytoplasm and is concentrated in stress granules where it is not associated with RNH1 and thus remains enzymatically active for tiRNA production. By contrast, nuclear ANG is associated with RNH1 in stressed cells to ensure that the enzymatic activity is inhibited and no unnecessary rRNA is produced to save anabolic energy. Knockdown of RNH1 abolished stress-induced relocalization of ANG and decreased cell growth and survival.
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Which is the subcellular localization of the protein angiogenin?
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Under growth conditions, ANG undergoes nuclear translocation and accumulates in the nucleolus where it stimulates rRNA transcription
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The methylation state of lysine 20 on histone H4 (H4K20) has been linked to chromatin compaction, transcription, DNA repair and DNA replication. Monomethylation of H4K20 (H4K20me1) is mediated by the cell cycle-regulated histone methyltransferase PR-Set7. PR-Set7 depletion in mammalian cells results in defective S phase progression and the accumulation of DNA damage, which has been partially attributed to defects in origin selection and activation. However, these studies were limited to only a handful of mammalian origins, and it remains unclear how PR-Set7 and H4K20 methylation impact the replication program on a genomic scale. We employed genetic, cytological, and genomic approaches to better understand the role of PR-Set7 and H4K20 methylation in regulating DNA replication and genome stability in Drosophila cells. We find that deregulation of H4K20 methylation had no impact on origin activation throughout the genome. Instead, depletion of PR-Set7 and loss of H4K20me1 results in the accumulation of DNA damage and an ATR-dependent cell cycle arrest. Coincident with the ATR-dependent cell cycle arrest, we find increased DNA damage that is specifically limited to late replicating regions of the Drosophila genome, suggesting that PR-Set7-mediated monomethylation of H4K20 is critical for maintaining the genomic integrity of late replicating domains.
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Is H4K20 methylation associated with DNA replication?
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The methylation state of lysine 20 on histone H4 (H4K20) has been linked to chromatin compaction, transcription, DNA repair and DNA replication.
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At the beginning of this century the compulsory vaccination and revaccination which was legally founded after the introduction of the vaccination by Jenner (1796) led to the removal of the smallpox in Europe and Northern America. However, up to the sixties in the developing countries of Asia, Africa as well as of Southern America and Middle America still fell ill and died of small-pox millions of people. Between 1953 and 1973 importations into countries of Europe and Northern America took place in 51 cases. In 1959 on the motion of the USSR the WHO decided performance of a world-wide eradication programme of small-pox which could be led to success with comprehensive personal, material and financial support of many countries. Flanking scientific, technological and methodical measures were of essential importance. In May 1980 the World Health Assembly in Geneva announced in solemn form the world-wide eradication of the small-pox and gave recommendations to the member countries for concluding measures concerning the small-pox vaccination, the foundation of vaccine reserves and the control of the epidemiological situation in the world. Also in the GDR the small-pox vaccination in childhood could be abolished.
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Has small pox been eradicated from the world?
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In May 1980 the World Health Assembly in Geneva announced in solemn form the world-wide eradication of the small-pox and gave recommendations to the member countries for concluding measures concerning the small-pox vaccination, the foundation of vaccine reserves and the control of the epidemiological situation in the world.
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Duchenne and Becker types of muscular dystrophy are usually differentiated according to age of onset and rate of progression criteria which are not sufficient. The aim of this paper was to re-establish the clues for distinguishing Duchenne from Becker types of muscular dystrophy. According to the onset and progression of the disease, one hundred and eleven patients were subdivided into two groups. First group--Becker muscular dystrophy--consisted of 40 patients and second one of 71 patients with Duchenne type of muscular dystrophy. Clinical data confirm some well known differences between Duchenne and Becker muscular dystrophy concerning the age of onset, severity of disease and rate of progression. Electromyographic signs of myopathic changes and spontaneous activity were found in both diseases. Spontaneous activity--bizarre and fibrillation potentials, as well as sharp waves are more common for Duchenne type. The differences between the Becker from Duchenne type of muscular dystrophy can be described on the basis of complex investigations (clinical, electromyographical, histological and biochemical).
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What is the difference between Duchenne muscular Dystrophy and Becker muscular dystrophy?
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Clinical data confirm some well known differences between Duchenne and Becker muscular dystrophy concerning the age of onset, severity of disease and rate of progression.
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We describe a case of a 42-year-old man, with a previous episode of angina and a normal ECG and serum cardiac markers, and a two months later finding of biphasic T wave in leads V2-V3 and deeply inverted T wave in V4-V5 at a asymptomatic occupational evaluation. This is a typical ECG pattern of Wellens' syndrome. A subsequent coronary angiography showed a critical stenosis of proximal left anterior descendent. We underline the careful value of prolonged observation in chest pain unit and repetitive ECG evaluation also during pain-free period after an angina episode, to exclude an earlier T wave pseudonormalization.
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Describe Wellens' Syndrome.
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We describe a case of a 42-year-old man, with a previous episode of angina and a normal ECG and serum cardiac markers, and a two months later finding of biphasic T wave in leads V2-V3 and deeply inverted T wave in V4-V5 at a asymptomatic occupational evaluation. This is a typical ECG pattern of Wellens' syndrome.
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The contribution of human subtelomeric DNA and chromatin organization to telomere integrity and chromosome end protection is not yet understood in molecular detail. Here, we show by ChIP-Seq that most human subtelomeres contain a CTCF- and cohesin-binding site within ∼1-2 kb of the TTAGGG repeat tract and adjacent to a CpG-islands implicated in TERRA transcription control. ChIP-Seq also revealed that RNA polymerase II (RNAPII) was enriched at sites adjacent to the CTCF sites and extending towards the telomere repeat tracts. Mutation of CTCF-binding sites in plasmid-borne promoters reduced transcriptional activity in an orientation-dependent manner. Depletion of CTCF by shRNA led to a decrease in TERRA transcription, and a loss of cohesin and RNAPII binding to the subtelomeres. Depletion of either CTCF or cohesin subunit Rad21 caused telomere-induced DNA damage foci (TIF) formation, and destabilized TRF1 and TRF2 binding to the TTAGGG proximal subtelomere DNA. These findings indicate that CTCF and cohesin are integral components of most human subtelomeres, and important for the regulation of TERRA transcription and telomere end protection.
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Does the CTCF protein co-localize with cohesin?
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These findings indicate that CTCF and cohesin are integral components of most human subtelomeres, and important for the regulation of TERRA transcription and telomere end protection
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Phospholamban (PLB) is a major target of the beta-adrenergic cascade in the heart, functioning to modulate contractile force by altering the rate of calcium re-sequestration by the Ca-ATPase. Functionally, inhibition by PLB binding is manifested by shifts in the calcium dependence of Ca-ATPase activation toward higher calcium levels; phosphorylation of PLB by PKA reverses the inhibitory action of PLB. To investigate structural changes in the cytoplasmic portion of PLB that result from either the phosphorylation of PLB by cAMP-dependent protein kinase (PKA) or calcium binding to the Ca-ATPase, we have used frequency-domain fluorescence spectroscopy to measure the spatial separation and conformational heterogeneity between N-(1-pyrenyl)maleimide, covalently bound to a single cysteine (Cys(24)) engineered near the membrane surface of the transmembrane domain of PLB, and Tyr(6) in the cytosolic domain. Irrespective of calcium activation of the Ca-ATPase or phosphorylation of Ser(16) in PLB by PKA, we find that PLB remains tightly associated with the Ca-ATPase in a well-defined conformation. However, calcium activation of the Ca-ATPase induces an increase in the overall dimensions of the cytoplasmic portion of bound PLB, whereas PLB phosphorylation results in a more compact structure, consistent with increased helical content induced by a salt link between phospho-Ser(16) and Arg(13). Thus, enzyme activation of the Ca-ATPase may occur through different mechanisms: calcium binding to high-affinity sites within the Ca-ATPase functions to overcome conformational constraints imposed by PLB on the N-domain of the Ca-ATPase; alternatively, phosphorylation stabilizes the backbone fold of PLB to release inhibitory interactions with the Ca-ATPase.
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Is phospholamban phosphorylated by Protein kinase A?
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Phospholamban (PLB) is a major target of the beta-adrenergic cascade in the heart, functioning to modulate contractile force by altering the rate of calcium re-sequestration by the Ca-ATPase. Functionally, inhibition by PLB binding is manifested by shifts in the calcium dependence of Ca-ATPase activation toward higher calcium levels; phosphorylation of PLB by PKA reverses the inhibitory action of PLB.
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Evolutionary innovation relies partially on changes in gene regulation. While a growing body of evidence demonstrates that such innovation is generated by functional changes or translocation of regulatory elements via mobile genetic elements, the de novo generation of enhancers from non-regulatory/non-mobile sequences has, to our knowledge, not previously been demonstrated. Here we show evidence for the de novo genesis of enhancers in vertebrates. For this, we took advantage of the massive gene loss following the last whole genome duplication in teleosts to systematically identify regions that have lost their coding capacity but retain sequence conservation with mammals. We found that these regions show enhancer activity while the orthologous coding regions have no regulatory activity. These results demonstrate that these enhancers have been de novo generated in fish. By revealing that minor changes in non-regulatory sequences are sufficient to generate new enhancers, our study highlights an important playground for creating new regulatory variability and evolutionary innovation.
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Is there evidence for de novo genesis of enhancers in vertebrates?
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Here we show evidence for the de novo genesis of enhancers in vertebrates.
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Modified nucleotides in messenger RNA (mRNA) have been discovered over 40 years ago, but until recently little was known about which transcripts contain them and what their function is. High-throughput sequencing approaches revealed a dynamic landscape of the 'Epitranscriptome' for many mRNA modifications in various organisms from yeast to humans. Meanwhile, also many genes encoding mRNA-modifying enzymes and auxiliary proteins have been identified yielding functional insights by reverse genetics into their role in development and disease.
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What is "Epitranscriptome analysis"?
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Modified nucleotides in messenger RNA (mRNA) have been discovered over 40 years ago, but until recently little was known about which transcripts contain them and what their function is. High-throughput sequencing approaches revealed a dynamic landscape of the 'Epitranscriptome' for many mRNA modifications in various organisms from yeast to humans.
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Extracellular ATP is an important signaling molecule throughout the inflammatory cascade, serving as a danger signal that causes activation of the inflammasome, enhancement of immune cell infiltration, and fine-tuning of several signaling cascades including those important for the resolution of inflammation. Recent studies demonstrated that ATP can be released from cells in a controlled manner through pannexin (Panx) channels. Panx1-mediated ATP release is involved in inflammasome activation and neutrophil/macrophage chemotaxis, activation of T cells, and a role for Panx1 in inducing and propagating inflammation has been demonstrated in various organs, including lung and the central and peripheral nervous system. The recognition and clearance of dying cells and debris from focal points of inflammation is critical in the resolution of inflammation, and Panx1-mediated ATP release from dying cells has been shown to recruit phagocytes. Moreover, extracellular ATP can be broken down by ectonucleotidases into ADP, AMP, and adenosine, which is critical in the resolution of inflammation. Together, Panx1, ATP, purinergic receptors, and ectonucleotidases contribute to important feedback loops during the inflammatory response, and thus represent promising candidates for new therapies.
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Where is the protein Pannexin1 located?
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Recent studies demonstrated that ATP can be released from cells in a controlled manner through pannexin (Panx) channels.
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Breast cancer is a very heterogeneous disease, encompassing several intrinsic subtypes with various morphological and molecular features, natural history and response to therapy. Currently, molecular targeted therapies are available for estrogen receptor (ER)(-) and human epidermal growth factor receptor 2 (Her2)-positive breast tumors. However, a significant proportion of primary breast cancers are negative for ER, progesterone receptor (PgR), and Her2, comprising the triple negative breast cancer (TNBC) group. Women with TNBC have a poor prognosis because of the aggressive nature of these tumors and current lack of suitable targeted therapies. As a consequence, the identification of novel relevant protein targets for this group of patients is of great importance. Using a systematic two dimensional (2D) gel-based proteomic profiling strategy, applied to the analysis of fresh TNBC tissue biopsies, in combination with a three-tier orthogonal technology (two dimensional PAGE/silver staining coupled with MS, two dimensional Western blotting, and immunohistochemistry) approach, we aimed to identify targetable protein markers that were present in a significant fraction of samples and that could define therapy-amenable sub-groups of TNBCs. We present here our results, including a large cumulative database of proteins based on the analysis of 78 TNBCs, and the identification and validation of one specific protein, Mage-A4, which was expressed in a significant fraction of TNBC and Her2-positive/ER negative lesions. The high level expression of Mage-A4 in the tumors studied allowed the detection of the protein in the tumor interstitial fluids as well as in sera. The existence of immunotherapeutics approaches specifically targeting this protein, or Mage-A protein family members, and the fact that we were able to detect its presence in serum suggest novel management options for TNBC and human epidermal growth factor receptor 2 positive/estrogen receptor negative patients bearing Mage-A4 positive tumors.
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Proteomic analyses have revealed proteins associated with the triple-negative breast cancers. List some proposed proteins.
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We present here our results, including a large cumulative database of proteins based on the analysis of 78 TNBCs, and the identification and validation of one specific protein, Mage-A4, which was expressed in a significant fraction of TNBC and Her2-positive/ER negative lesions.
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Protein phosphorylation-dephosphorylation events play a primary role in regulation of almost all aspects of cell function including signal transduction, cell cycle, or apoptosis. Thus far, T cell phosphoproteomics have focused on analysis of phosphotyrosine residues, and little is known about the role of serine/threonine phosphorylation in early activation of the T cell receptor (TCR). Therefore, we performed a quantitative mass spectrometry-based analysis of the global phosphoproteome of human primary T cells in response to 5 min of TCR activation with anti-CD3 antibody. Combining immunoprecipitation with an antiphosphotyrosine antibody, titanium dioxide phosphopeptide enrichment, isobaric tag for the relative and absolute quantitation methodology, and strong cation exchange separation, we were able to identify 2814 phosphopeptides. These unique sites were employed to investigate the site-specific phosphorylation dynamics. Five hundred and seventeen phosphorylation sites showed TCR-responsive changes. We found that upon 5 min of stimulation of the TCR, specific serine and threonine kinase motifs are overrepresented in the set of responsive phosphorylation sites. These phosphorylation events targeted proteins with many different activities and are present in different subcellular locations. Many of these proteins are involved in intracellular signaling cascades related mainly to cytoskeletal reorganization and regulation of small GTPase-mediated signal transduction, probably involved in the formation of the immune synapse.
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Global quantitative phosphoproteomic analyses are emerging. List the preferred technologies for the enrichment for phosphorylated peptides?
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Combining immunoprecipitation with an antiphosphotyrosine antibody, titanium dioxide phosphopeptide enrichment, isobaric tag for the relative and absolute quantitation methodology, and strong cation exchange separation, we were able to identify 2814 phosphopeptides.
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The muscular dystrophy is a group of inherited disorders characterized in the most of cases by progressive muscle weakness. The best known are X-linked disorder Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). BMD is a milder form of the disease with a later age of onset and a slower clinical progression. The DMD gene, located on Xp21, is the largest human gene in the human genome (2.3 Mb). DMD gene consists of 79 exons and codes for dystrophin protein. A 9-year-old boy, who experienced symptoms of the disease, was admitted to the Casablanca University Children's Hospital. The patient, with no known family history of significant muscle disease, was first examined at 4 years of age because of walking difficulties and a limited hands force. Blood tests revealed elevated serum levels of creatine kinase (7.60 U/L). The electromyogram showed myopathic changes, consisting of polyphasic potentials, and the muscular biopsy revealed dystrophic aspect. Analysis of the dystrophin-encoding gene by PCR deletion analysis of the dystrophin gene was performed by multiplex PCR primer sets of Chamberlain and Beggs. The analysis showed a deletion of exons 45 to 49. Mother genetic testing showed the heterozygosis deletion.
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Where is the DMD gene located?
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The DMD gene, located on Xp21, is the largest human gene in the human genome (2.
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Numerous abnormalities of thyroid hormones in end-stage renal disease (ESRD) have been described. Our aim was to analyze the impact of these abnormalities on survival. In 167 hemodialyzed ESRD patients, TSH and thyroid hormone levels (T4, fT4, T3, fT3, rT3) were determined. The patients were then prospectively followed up for up to 5 years and the possible impact of any observed abnormalities on their mortality was studied. Only 16.8 % patients had all six tests within the reference range. The pattern of nonthyroidal illness syndrome was found in 56.3 %. Low T3 was particularly common (44.3 %), and clearly associated with increased 6- and 12-month mortality and decreased overall survival (log rank test, P=0.007). Independent of T3 levels (Spearman correlation, NS), increased rT3 was more frequently observed (9.9 %) than expected from the literature, and was also related to increased mortality and decreased survival (log rank test, P=0.021). Increased rT3 may be more common in ESRD patients than previously described, and together with decreased T3 it may serve as an indicator of poor prognosis in subsequent months.
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Is low T3 syndrome a prognostic marker in patients with renal insufficiency?
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Increased rT3 may be more common in ESRD patients than previously described, and together with decreased T3 it may serve as an indicator of poor prognosis in subsequent months.
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Hepcidin is encoded as an 84 amino acid prepropeptide containing a typical N-terminal 24 amino acid endoplasmic reticulum targeting signal sequence, and a 35 amino acid proregion (pro) with a consensus furin cleavage site immediately followed by the C-terminal 25 amino acid bioactive iron-regulatory hormone (mature peptide). We performed pulse-chase studies of posttranslational processing of hepcidin in human hepatoma HepG2 cells and in primary human hepatocytes induced with bone morphogenic protein (BMP-9). In some experiments, the cells were treated with the furin protease inhibitor decanoyl-Arg-Val-Lys-Arg-chloromethylketone (CMK) or furin siRNA. In the absence of furin inhibitor, hepcidin was found to be processed in less than 1 h and secreted as a 3 kDa form reactive with anti-mature but not anti-pro antibody. In the presence of furin inhibitors or furin siRNA, a 6 kDa form reactive with both anti-pro and anti-mature antibody was rapidly secreted into the medium. Processing was not affected by inhibitors of the hypoxia inducible factor (HIF) pathway, or by treatment with 30 microM holo- or apo-transferrin. In conclusion, the hepatic prohormone convertase furin mediates the posttranslational processing of hepcidin. The proteolytic cleavage of prohepcidin to hepcidin is not regulated by iron-transferrin or the HIF pathway.
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What is the connection between furin and hepcidin?
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In conclusion, the hepatic prohormone convertase furin mediates the posttranslational processing of hepcidin.
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The dopaminergic stabilizer pridopidine demonstrates state-dependent effects on locomotor activity, counteracting both hypo- and hyperactivity in rats. Pridopidine has been shown to display both functional dopamine D2 receptor antagonist properties and increase in biomarkers associated with NMDA-mediated glutamate transmission in the frontal cortex. To further characterise the effects of pridopidine on prefrontal cortex (PFC) neurons, a series of in vivo electrophysiological studies were performed in urethane-anaesthetised rats. Pridopidine, administered at doses from 10 to 60 mg/kg (i.v.), dose dependently increased pyramidal cell firing in the majority of the neurons tested. Pridopidine induced a significant increase of 162 % in mean firing activity of PFC neurons, versus initial basal firing activity as the cumulative dose of 30 mg/kg, i.v., was administered. This enhancement of activity was due to increased firing frequency of already spontaneously active neurons, rather than an increase in population activity. The increase was partially reversed or prevented by a sub-threshold dose of the dopamine D1 receptor antagonist SCH23390 (0.5 mg/kg, i.v.). Microiontophoretic application of pridopidine had only moderate activating effects. The selective dopamine D1 receptor agonist A-68930 also had limited effects when administered by microiontophoretic application, but exerted a dose dependent (0.2-3 mg/kg, i.v.) activation of firing in the majority of neurons tested (10/16). However, inhibition of firing by systemic administration of A-68930 was also observed in a subgroup of neurons (6/16). Both activation and inhibition of firing induced by systemic administration of A-68930 were reversed by the systemic administration of SCH23390. The present data suggests that pridopidine enhances pyramidal cell firing via an indirect dopamine D1 receptor-mediated mechanism. These effects of pridopidine may serve to strengthen the cortico-striatal communication and to improve motor control in Huntington's disease for which pridopidine is currently in development.
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Pridopidine has been tested for treatment of which disorder?
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These effects of pridopidine may serve to strengthen the cortico-striatal communication and to improve motor control in Huntington's disease for which pridopidine is currently in development.
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The amyloid hypothesis has long been the central dogma in drug discovery for Alzheimer's disease (AD), leading to many small-molecule and biological drug candidates. One major target has been the β-site amyloid-precursor-protein-cleaving enzyme 1 (BACE-1), with many big pharma companies expending great resources in the search for BACE-1 inhibitors. The lack of efficacy of verubecestat in mild-to-moderate AD raises important questions about the timing of intervention with BACE-1 inhibitors, and anti-amyloid therapies in general, in AD treatment. It also suggests new possibilities for discovering BACE-1-targeted compounds with more complex mechanisms of actions and improved efficacy. Herein, we review the major advances in BACE-1 drug discovery, from single-target small molecule inhibitors to multitarget compounds. We discuss these compounds as innovative tools for better understanding the complexity of AD and for identifying efficacious drug candidates to treat this devastating disease.
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Is Verubecestat effective for Alzheimer's Disease?
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The lack of efficacy of verubecestat in mild-to-moderate AD raises important questions about the timing of intervention with BACE-1 inhibitors, and anti-amyloid therapies in general, in AD treatment.
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Small deletions and duplications frequently occur in the pericentromeric region of chromosomes and many of these are associated with developmental abnormalities. These developmental syndromes are conventionally attributed to abnormal expression of protein-coding genes in the affected region. A hypothesis has recently been published concerning a Master Development Program based on noncoding transcripts from these regions (Parris GE. A hypothetical Master Development Program for multi-cellular organisms: Ontogeny and phylogeny. Biosci Hypotheses 2009;2:3-12.). This paper summarizes and expands the recently published hypothesis to include it application to developmental diseases. The author proposes that development of multi-cellular organisms is guided by a Master Development Program (MDP) located primarily in the pericentromeric heterochromatin. The MDP is believed to consist of a series of Generation-Specific Control Keys (GSCK) transcribed in sequence by Ikaros family transcription factors unless the GSCKs are suppressed by Sall1-family or Dnmt3b-family proteins. The MDP is proposed to increment with each cell cycle to the next GSCK resulting in development of the clone. A clone may be programmed to split into two clones as necessary through a two-cycle mitosis processes. The transcripts of the GSCKs presumably yield noncoding nuclear messenger RNAs (nmRNAs, 8-30 nt units) that act directly (e.g., as primers for RNA polymerase II) and indirectly to regulate HOX and other high-level transcription factor and developmental genes. As envisioned, the MDP would evolve by terminal addition of new GSCKs. The new GSCKs are produced by evolutionary consolidation of retro-transcripts into pyknons that collect and evolve at the end of the pericentromeric heterochromatin and are eventually incorporated into the MDP. The retro-transcripts are though to be produced during episodic retrovirus epidemics and account for punctuated equilibrium in species evolution.
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Which is the definition of pyknons in DNA?
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The new GSCKs are produced by evolutionary consolidation of retro-transcripts into pyknons that collect and evolve at the end of the pericentromeric heterochromatin and are eventually incorporated into the MDP
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During adult homeostasis and regeneration, the freshwater planarian must accomplish a constant balance between cell proliferation and cell death, while also maintaining proper tissue and organ size and patterning. How these ordered processes are precisely modulated remains relatively unknown. Here we show that planarians use the downstream effector of the Hippo signaling cascade, yorkie (yki; YAP in vertebrates) to control a diverse set of pleiotropic processes in organ homeostasis, stem cell regulation, regeneration and axial patterning. We show that yki functions to maintain the homeostasis of the planarian excretory (protonephridial) system and to limit stem cell proliferation, but does not affect the differentiation process or cell death. Finally, we show that Yki acts synergistically with WNT/β-catenin signaling to repress head determination by limiting the expression domains of posterior WNT genes and that of the WNT-inhibitor notum. Together, our data show that yki is a key gene in planarians that integrates stem cell proliferation control, organ homeostasis, and the spatial patterning of tissues.
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Is the Wnt protein modified by notum?
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the WNT-inhibitor notum.
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Radiation-induced sarcomas are recognized complications of radiation therapy and are associated with poor prognosis. Radiation-induced osteosarcoma is one of the rare types of radiation-induced sarcomas, with the risk of radiation-induced osteosarcomas being only 0.01%-0.03% among all patients treated with radiotherapy. There have been only four reported cases of radiation-induced osteosarcomas after radiotherapy for gliomas. Here, we report a unique case of radiation-induced osteosarcomas arising on the skull and extending to the skin, with a short latent period. We also review the clinical features of the previously reported cases.
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Can radiotherapy cause radiation induced osteosarcoma?
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Here, we report a unique case of radiation-induced osteosarcomas arising on the skull and extending to the skin, with a short latent period.
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In metazoans, enhancers of gene transcription must often exert their effects over tens of kilobases of DNA. Over the past decade it has become clear that to do this, enhancers come into close proximity with target promoters with the looping away of intervening sequences. In a few cases proteins that are involved in the establishment or maintenance of these loops have been revealed but how the proper gene target is selected remains mysterious. Chromatin insulators had been appreciated as elements that play a role in enhancer fidelity through their enhancer blocking or barrier activity. However, recent work suggests more direct participation of insulators in enhancer-gene interactions. The emerging view begins to incorporate transcription activation by distant enhancers with large scale nuclear architecture and subnuclear movement.
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Do enhancers have to be close to their gene targets?
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In metazoans, enhancers of gene transcription must often exert their effects over tens of kilobases of DNA. Over the past decade it has become clear that to do this, enhancers come into close proximity with target promoters with the looping away of intervening sequences.
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Lacosamide (LCM) is a newer antiepileptic drug with a dual mode of action. It selectively enhances slow inactivation of voltage-gated sodium channels without affecting fast inactivation, and modulates collapsing response mediator protein 2 (CRMP-2). It has a high oral bioavailability of approximately 100%. It has shown potent and broad neuroprotective effects in vitro and in vivo animal models making it a potential candidate for long term treatment of epilepsy. In addition to this, it has demonstrated analgesic activity in various animal models. Apart from this, LCM has demonstrated potent effects in animal models for a variety of CNS disorders like schizophrenia and stress induced anxiety. Various safety pharmacology and toxicology studies have shown that LCM is well tolerated. Clinical trials have also suggested that LCM is a safe, effective, and well tolerated adjunctive treatment for reduction of seizure frequency in patients with highly refractory, partial seizures. Other potential indications of LCM are being investigated.
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What are the main indications of lacosamide?
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Lacosamide (LCM) is a newer antiepileptic drug with a dual mode of action.
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Hemophilic pseudotumor is a rare, but well-known, complication of hemophilia. We describe a 50-year-old man with mild hemophilia A, but with no previous need for Factor VIII supplementation, who presented with a pathologic fracture of the right femoral neck and shaft caused by a large hemophilic pseudotumor. Initial nonoperative therapy with factor replacement and skeletal traction resulted in radiographic evidence of fracture healing, but the patient's pain persisted. Therefore, he had a radical resection of his hemophilic pseudotumor (soft tissue component and entire femur), and reconstruction with a custom total femoral replacement. Six months after resection, the patient returned to full-time employment. Although pseudotumor formation is a well-recognized complication of hemophilia, the pseudotumor in our study is one of the largest yet described. More importantly, to our knowledge this is the first report of a pseudotumor treated by radical resection and reconstruction with a custom femoral prosthesis. We think that radical resection and reconstruction with a custom total femoral prosthesis is a valuable alternative to amputation in massive pseudotumors of the femur and soft tissues of the thigh.
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What is Hemophilic Pseudotumor?
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Although pseudotumor formation is a well-recognized complication of hemophilia, the pseudotumor in our study is one of the largest yet described.
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Fluorescent reporter proteins based on flavin-binding photosensors were recently developed as a new class of genetically encoded probes characterized by small size and oxygen-independent maturation of fluorescence. Flavin-based fluorescent proteins (FbFPs) address two major limitations associated with existing fluorescent reporters derived from the green fluorescent protein (GFP)-namely, the overall large size and oxygen-dependent maturation of fluorescence of GFP. However, FbFPs are at a nascent stage of development and have been utilized in only a handful of biological studies. Importantly, a full understanding of the performance and properties of FbFPs as a practical set of biological probes is lacking. In this work, we extensively characterize three FbFPs isolated from Pseudomonas putida, Bacillus subtilis, and Arabidopsis thaliana, using in vitro studies to assess probe brightness, oligomeric state, maturation time, fraction of fluorescent holoprotein, pH tolerance, redox sensitivity, and thermal stability. Furthermore, we validate FbFPs as stable molecular tags using in vivo studies by constructing a series of FbFP-based transcriptional constructs to probe promoter activity in Escherichia coli. Overall, FbFPs show key advantages as broad-spectrum biological reporters including robust pH tolerance (4-11), thermal stability (up to 60°C), and rapid maturation of fluorescence (<3 min.). In addition, the FbFP derived from Arabidopsis thaliana (iLOV) emerged as a stable and nonperturbative reporter of promoter activity in Escherichia coli. Our results demonstrate that FbFP-based reporters have the potential to address key limitations associated with the use of GFP, such as pH-sensitive fluorescence and slow kinetics of fluorescence maturation (10-40 minutes for half maximal fluorescence recovery). From this view, FbFPs represent a useful new addition to the fluorescent reporter protein palette, and our results constitute an important framework to enable researchers to implement and further engineer improved FbFP-based reporters with enhanced brightness and tighter flavin binding, which will maximize their potential benefits.
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List fluorescent reporter proteins.
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Flavin-based fluorescent proteins (FbFPs)
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Proper development of the immune system is an intricate process dependent on many factors, including an intact DNA damage response. The DNA double-strand break signaling kinase ATM and its cofactor NBS1 are required during T cell development and for the maintenance of genomic stability. The role of a second ATM cofactor, ATMIN (also known as ASCIZ) in T cells is much less clear, and whether ATMIN and NBS1 function in synergy in T cells is unknown. Here, we investigate the roles of ATMIN and NBS1, either alone or in combination, using murine models. We show loss of NBS1 led to a developmental block at the double-positive stage of T cell development, as well as reduced TCRα recombination, that was unexpectedly neither exacerbated nor alleviated by concomitant loss of ATMIN. In contrast, loss of both ATMIN and NBS1 enhanced DNA damage that drove spontaneous peripheral T cell hyperactivation, proliferation as well as excessive production of proinflammatory cytokines and chemokines, leading to a highly inflammatory environment. Intriguingly, the disease causing T cells were largely proficient for both ATMIN and NBS1. In vivo this resulted in severe intestinal inflammation, colitis and premature death. Our findings reveal a novel model for an intestinal bowel disease phenotype that occurs upon combined loss of the DNA repair cofactors ATMIN and NBS1.
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What is the role of DNA Repair Cofactors ATMIN and NBS1?
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Our findings reveal a novel model for an intestinal bowel disease phenotype that occurs upon combined loss of the DNA repair cofactors ATMIN and NBS1.
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The establishment of cell fates involves alterations of transcription factor repertoires and repurposing of transcription factors by post-translational modifications. In embryonic stem cells (ESCs), the chromatin organizers SATB2 and SATB1 balance pluripotency and differentiation by activating and repressing pluripotency genes, respectively. Here, we show that conditional gene inactivation weakens ESC pluripotency, and we identify SUMO2 modification of SATB2 by the E3 ligase ZFP451 as a potential driver of ESC differentiation. Mutations of two SUMO-acceptor lysines of ( ) or knockout of impair the ability of ESCs to silence pluripotency genes and activate differentiation-associated genes in response to retinoic acid (RA) treatment. Notably, the forced expression of a SUMO2-SATB2 fusion protein in either or ESCs rescues, in part, their impaired differentiation potential and enhances the down-regulation of The differentiation defect of ESCs correlates with altered higher-order chromatin interactions relative to ESCs. Upon RA treatment of ESCs, SATB2 interacts with ZFP451 and the LSD1/CoREST complex and gains binding at differentiation genes, which is not observed in RA-treated cells. Thus, SATB2 SUMOylation may contribute to the rewiring of transcriptional networks and the chromatin interactome of ESCs in the transition of pluripotency to differentiation.
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Is Satb1 a transcription factor?
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chromatin organizers SATB2 and SATB1
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The interaction between the (epi)genetic makeup of an individual and his/her environmental exposure record (exposome) is accepted as a determinant factor for a significant proportion of human malignancies. Recent evidence has highlighted the key role of epigenetic mechanisms in mediating gene-environment interactions and translating exposures into tumorigenesis. There is also growing evidence that epigenetic changes may be risk factor-specific ("fingerprints") that should prove instrumental in the discovery of new biomarkers in cancer. Here, we review the state of the science of epigenetics associated with environmental stimuli and cancer risk, highlighting key developments in the field. Critical knowledge gaps and research needs are discussed and advances in epigenomics that may help in understanding the functional relevance of epigenetic alterations. Key elements required for causality inferences linking epigenetic changes to exposure and cancer are discussed and how these alterations can be incorporated in carcinogen evaluation and in understanding mechanisms underlying epigenome deregulation by the environment.
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What is a exposome?
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The interaction between the (epi)genetic makeup of an individual and his/her environmental exposure record (exposome) is accepted as a determinant factor for a significant proportion of human malignancies.
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Focal cortical dysplasias are a well-recognized cause of medically intractable seizures. The clinical relevance of certain subgroups of the International League Against Epilepsy (ILAE) classification scheme remains to be determined. The aim of the present work is to assess the effect of the focal cortical dysplasia type Ib and Ic histologic subtypes on surgical outcome with respect to seizure frequency. This study also provides an opportunity to compare the predictive value of the ILAE and Palmini et al classification schemes with regard to the type I focal cortical dysplasias. We retrospectively reviewed 91 focal cortical dysplasia patients (55% female; median age: 19 years (interquartile range 8-34); median seizure duration: 108 months (interquartile range 36-204)) with chronic epilepsy who underwent surgery. We compared the pathological subtypes, evaluating the patients' post-surgical outcome with respect to seizure frequency according to the Engel's classification and the ILAE outcome classification. Both the ILAE classification scheme and Palmini et al classification scheme were utilized to classify the histologic subtype. Using χ(2) and Fisher's exact tests, we compared the post-surgical outcomes among these groups. Of the 91 patients, there were 50 patients with ILAE focal cortical dysplasia type Ib, 41 with ILAE focal cortical dysplasia type Ic, 63 with Palmini et al focal cortical dysplasia type IA, and 28 with Palmini et al focal cortical dysplasia type IB. After surgery, 44 patients (48%) were seizure-free. Crude analysis revealed no significant difference between patients with subtypes of ILAE focal cortical dysplasia type I or Palmini et al focal cortical dysplasia type I concerning postoperative outcome according to the Engel and ILAE scoring systems on seizure frequency. Our findings revealed no significant difference concerning surgical outcome with respect to seizure frequency for the histologic subtypes of ILAE focal cortical dysplasia type I (Ib vs Ic) or Palmini et al focal cortical dysplasia type I (IA vs IB). In isolation, the histologic subtype of focal cortical dysplasia type I does not appear predictive of postoperative outcome.
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Which disorder is rated by Palmini classification?
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Crude analysis revealed no significant difference between patients with subtypes of ILAE focal cortical dysplasia type I or Palmini et al focal cortical dysplasia type I concerning postoperative outcome according to the Engel and ILAE scoring systems on seizure frequency.
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Proteins on the surface of parasite-infected erythrocytes (PIESPs) have been one of the major focuses of malaria research due to their role in pathogenesis and their potential as targets for immunity and drug intervention. Despite intense scrutiny, only a few surface proteins have been identified and characterized. We report the identification of two novel surface proteins from Plasmodium falciparum-infected erythrocytes. Surface proteins were fractionated through biotin-streptavidin interaction and analyzed by shotgun proteomics. From a list of 36 candidates, two were selected for further characterization. The surface location of both proteins was confirmed by confocal microscopy using specific antibodies. PIESP1 and PIESP2 are unlikely to be associated with knobs, the protrusions on the parasite-infected erythrocyte (PIE) surface. In contrast to other known PIESPs, such as PfEMP1 and Rifin, these novel proteins are encoded by single copy genes, highly conserved across Plasmodium ssp., making them good targets for interventions with a broad specificity to various P. falciparum isolates.
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Which is the localization of the RIFIN family of proteins?
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In contrast to other known PIESPs, such as PfEMP1 and Rifin,
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We live in an age of access to more information than ever before. This can be a double-edged sword. Increased access to information allows for more informed and empowered researchers, while information overload becomes an increasingly serious risk. Thus, there is a need for intelligent information retrieval systems that can summarize relevant and reliable textual sources to satisfy a user's query. Question answering is a specialized type of information retrieval with the aim of returning precise short answers to queries posed as natural language questions. We present a review and comparison of three biomedical question answering systems: askHERMES (http://www.askhermes.org/), EAGLi (http://eagl.unige.ch/EAGLi/), and HONQA (http://services.hon.ch/cgi-bin/QA10/qa.pl).
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List available biomedical question answering systems.
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We present a review and comparison of three biomedical question answering systems: askHERMES (http://www.
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Late gadolinium enhancement is the technique of choice for detecting myocardial fibrosis. Although this technique is used in a wide range of cardiovascular pathologies, ischemic cardiomyopathy and the workup for myocarditis and other cardiomyopathies make up a significant proportion of the total indications. Multiple studies during the last decade have demonstrated its utility to adequately characterize myocardial tissue and offer diagnostic and prognostic information. Recent T1 mapping techniques aim to overcome the limitations of late gadolinium enhancement to assess diffuse fibrosis. ¹⁹F magnetic resonance has recently emerged as a promising technique for the assessment of inflammation. In the following review we will discuss the basic aspects of fibrosis assessment with MR and its utility for diagnostic and prognostic evaluation. We will also address the topic of cardiovascular inflammation imaging with ¹⁹F as a potential new development that may broaden the indications for MR in the future.
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What is the clinical indication of cardiac T1 mapping magnetic resonance?
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Recent T1 mapping techniques aim to overcome the limitations of late gadolinium enhancement to assess diffuse fibrosis.
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The tafazzin gene encodes a phospholipid-lysophospholipid transacylase involved in cardiolipin metabolism, but it is not known why it forms multiple transcripts as a result of alternative splicing. Here we studied the intracellular localization, enzymatic activity, and metabolic function of four isoforms of human tafazzin and three isoforms of Drosophila tafazzin upon expression in different mammalian and insect systems. When expressed in HeLa cells, all isoforms were localized in mitochondria except for the B-form of Drosophila tafazzin, which was associated with multiple intracellular membranes. Among the human isoforms, only full-length tafazzin (FL) and tafazzin lacking exon 5 (Delta5) had transacylase activity, and only these two isoforms were able to restore a normal cardiolipin pattern, normal respiratory activity of mitochondria, and male fertility in tafazzin-deficient flies. Both FL and Delta5 were associated with large protein complexes in 293T cell mitochondria, but treatment with alkali and proteinase K suggested that the Delta5 isoform was more integrated into the hydrophobic core of the membrane than the FL isoform. Although all Drosophila isoforms showed transacylase activity in vitro, only the A-form supported cardiolipin remodeling in flies. The data suggest that humans express two mitochondrial isoenzymes of tafazzin that have similar transacylase activities but different membrane topologies. Furthermore, the data show that the expression of human tafazzin in flies creates cardiolipin with a Drosophila pattern, suggesting that the characteristic fatty acid profile of cardiolipin is not determined by the substrate specificity of tafazzin.
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What is the function of the protein tafazzin?
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Among the human isoforms, only full-length tafazzin (FL) and tafazzin lacking exon 5 (Delta5) had transacylase activity, and only these two isoforms were able to restore a normal cardiolipin pattern, normal respiratory activity of mitochondria, and male fertility in tafazzin-deficient flies.
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The ability of bicuculline, a GABA antagonist, to enhance dopamine (DA) synthesis in retinas of rats 1, 4, 7, 15 and 60 days after eye opening was assessed and compared to the time course of postnatal development of the light-induced increase in DA synthesis. The accumulation of dihydroxyphenylalanine (DOPA) following administration of the L-aromatic amino acid decarboxylase inhibitor, NSD 1015, was used to estimate DA synthesis. In dark-adapted rats, neither bicuculline nor light enhanced DOPA accumulation 1 day after eye opening, but on the remaining days either treatment significantly augmented DA synthesis, and by day 15 the effects were as great as those observed in adult retinas. At each time point, the magnitude of the drug effect on DA synthesis in the dark was similar to that observed following light exposure. These results suggest that an endogenous GABAergic input to the DA neurons appears at the same time as the acquisition of the dopaminergic response to light. The effect of bicuculline treatment on DA synthesis in light-exposed animals was also assessed. At 4 and 7 days the drug significantly enhanced DOPA accumulation over that produced by exposure to light alone, but on later days bicuculline exerted no such additive effect. These data imply that early in the maturation of the light response mechanisms other than removal of an inhibitory GABAergic tone may be partially responsible for excitation of the DA neurons.
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Is NSD-1015 an inhibitor of Aromatic L-Amino Acid Decarboxylase?
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The accumulation of dihydroxyphenylalanine (DOPA) following administration of the L-aromatic amino acid decarboxylase inhibitor, NSD 1015, was used to estimate DA synthesis.
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Pheochromocytomas synthesize and release catecholamines, which subsequently are related to various clinical manifestations of the disease. However, pheochromocytomas are not innervated and the catecholamine release and synthesis are not initiated by neural impulses. It is still unknown how catecholamine synthesis is regulated in pheochromocytomas. As a first step toward understanding the molecular mechanisms by which catecholamine synthesis is controlled in the tumor, we measured the levels of mRNA coding for the catecholamine synthesizing enzyme, tyrosine hydroxylase (TH) and catecholamines in 6 pheochromocytomas and 2 normal adrenal glands. The TH mRNA level was overexpressed and the catecholamine contents were high in 4 out of 6 pheochromocytomas. There was a close correlation between the TH mRNA level and the catecholamines content in the tumors. We also examined the gene expression of the messengers of other catecholamine synthesizing enzymes, dopamine beta-hydroxylase (DBH) and aromatic 1-amino acid decarboxylase (AADC) in pheochromocytomas. The expression of these genes was in parallel with that of TH mRNA in the tumors. These findings indicate that catecholamine overproduction in pheochromocytomas is mediated by the overexpression of genes coding for catecholamines synthesizing enzymes, TH, DBH, and AADC.
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Which enzymes synthesize catecholamines in adrenal glands?
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As a first step toward understanding the molecular mechanisms by which catecholamine synthesis is controlled in the tumor, we measured the levels of mRNA coding for the catecholamine synthesizing enzyme, tyrosine hydroxylase (TH) and catecholamines in 6 pheochromocytomas and 2 normal adrenal glands
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A human genetic defect associated with 'long Q-T syndrome', an abnormality of cardiac rhythm involving the repolarization of the action potential, was recently found to lie in the HERG gene, which codes for a potassium channel. The HERG K+ channel is unusual in that it seems to have the architectural plan of the depolarization-activated K+ channel family (six putative transmembrane segments), yet it exhibits rectification like that of the inward-rectifying K+ channels, a family with different molecular structure (two transmembrane segments). We have studied HERG channels expressed in mammalian cells and find that this inward rectification arises from a rapid and voltage-dependent inactivation process that reduces conductance at positive voltages. The inactivation gating mechanism resembles that of C-type inactivation, often considered to be the 'slow inactivation' mechanism of other K+ channels. The characteristics of this gating suggest a specific role for this channel in the normal suppression of arrhythmias.
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Does the hERG gene code for a protein which is part of a sodium channel?
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A human genetic defect associated with 'long Q-T syndrome', an abnormality of cardiac rhythm involving the repolarization of the action potential, was recently found to lie in the HERG gene, which codes for a potassium channel.
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The social impairments of autism spectrum disorder (ASD) have a major impact on quality of life, yet there are no medications that effectively treat these core social behavior deficits. Preclinical research suggests that arginine vasopressin (AVP), a neuropeptide involved in promoting mammalian social behaviors, may be a possible treatment for ASD. Using a double-blind, randomized, placebo-controlled, parallel study design, we tested the efficacy and tolerability of a 4-week intranasal AVP daily treatment in 30 children with ASD. AVP-treated participants aged 6 to 9.5 years received the maximum daily target dose of 24 International Units (IU); participants aged 9.6 to 12.9 years received the maximum daily target dose of 32 IU. Intranasal AVP treatment compared to placebo enhanced social abilities as assessed by change from baseline in this phase 2 trial's primary outcome measure, the Social Responsiveness Scale, 2nd Edition total score (SRS-2 score; = 9.853; = 0.0052; η = 33.0%; Cohen's = 1.40). AVP treatment also diminished anxiety symptoms and some repetitive behaviors. Most of these findings were more pronounced when we accounted for pretreatment AVP concentrations in blood. AVP was well tolerated with minimal side effects. No AVP-treated participants dropped out of the trial, and there were no differences in the rate of adverse events reported between treatment conditions. Last, no changes from baseline were observed in vital signs, electrocardiogram tracings, height and body weight, or clinical chemistry measurements after 4 weeks of AVP treatment. These preliminary findings suggest that AVP has potential for treating social impairments in children with ASD.
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Is autism thought to be related to the Arginine Vasopressin Peptide (AVP)?
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Preclinical research suggests that arginine vasopressin (AVP), a neuropeptide involved in promoting mammalian social behaviors, may be a possible treatment for ASD.
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Mulibrey nanism (muscle-liver-brain-eye nanism; MUL) is an autosomal recessively transmitted disease characterized by severe growth delays of prenatal onset caused by mutations in the TRIM37 gene. Recent studies on the subcellular localization revealed that the TRIM37 (KIAA0898) protein is located in peroxisomes. Therefore, MUL has been classified as a new peroxisomal disorder. Up to now, four mutations have been reported, all of which lead to frameshifts and truncated proteins. In this study, mutation screening was performed for the coding region of the TRIM37 gene in a Turkish family by means of RT-PCR and direct cDNA sequencing. We have identified a novel mutation resulting in a frameshift cosegregating within the family. Finally, we report on the presence of novel splice variants observed in lymphoblastoid cells and muscle tissue of normal subjects and patients.
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Does TRIM37 gene mutation causes Mulibrey nanism?
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Mulibrey nanism (muscle-liver-brain-eye nanism; MUL) is an autosomal recessively transmitted disease characterized by severe growth delays of prenatal onset caused by mutations in the TRIM37 gene.
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In recent years, the introduction and Federal Drug Administration approval of immune checkpoint inhibitor antibodies has dramatically improved the clinical outcomes for patients with advanced melanoma. These antagonist monoclonal antibodies are capable of unleashing dormant or exhausted antitumor immunity, which has led to durable complete and partial responses in a large number of patients. Ipilimumab targets the cytotoxic T lymphocyte-associated protein 4 (CTLA-4) receptor. Nivolumab and pembrolizumab target programmed cell death protein 1 (PD-1) receptors and have proven to be superior to ipilimumab alone. The combination of ipilimumab and nivolumab has yielded higher response rates, greater tumor shrinkage, and longer progression-free survival than either monotherapy alone. As other promising immunotherapies for melanoma proceed through clinical trials, future goals include defining the role of immune checkpoint inhibitors as adjuvant therapy, identifying optimal combination strategies, and developing reliable predictive biomarkers to guide treatment selection for individual patients.
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What are PD-1 inhibitors?
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Nivolumab and pembrolizumab target programmed cell death protein 1 (PD-1) receptors and have proven to be superior to ipilimumab alone. T
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Awareness of the risk of airborne transmission of SARS-CoV-2 makes patients hesitant about using inhaled medications that are considered as a potential source of viral transmission and immunosuppression. However, patients with asthma or COPD should continue all prescribed inhaled medications. Apparently, inhalers, including pMDIs, DPIs, or SMIs, have a low risk of contamination although characteristics of drug formulation can precipitate cough, whereas some researchers do not rule out the probability that nebulizer treatments may increase the risk of infection transmission via droplet nuclei and aerosols. Considering that aerosol therapy generates fugitive emissions that are not inhaled by the patient and are released from the device during expiration, several international professional bodies have provided recommendations for drug delivery via inhalers and in particular, nebulizers. Unfortunately, these recommendations are often in conflict with each other and do not clarify whether it is appropriate to use nebulizers during this COVID-19 pandemic. Considering what is available in literature, there are no known infection-related hazards to an uninfected patient and also a patient with COVID-19 that preclude the use of a nebulizer at home, but it fundamental that all patients, regardless of whether or not suffering from COVID-19, always follow some practical advices.
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Should patients using inhaled glucocorticoids for asthma or COPD be advised to stop these medications to prevent COVID-19?
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However, patients with asthma or COPD should continue all prescribed inhaled medications.
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In growing cells, apurinic/apyrimidinic (AP) sites generated spontaneously or resulting from the enzymatic elimination of oxidized bases must be processed by AP endonucleases before they compromise cell integrity. Here, we investigated how AP sites and the processing of these noncoding lesions by the AP endonucleases Nfo, ExoA, and Nth contribute to the production of mutations (hisC952, metB5, and leuC427) in starved cells of the Bacillus subtilis YB955 strain. Interestingly, cells from this strain that were deficient for Nfo, ExoA, and Nth accumulated a greater amount of AP sites in the stationary phase than during exponential growth. Moreover, under growth-limiting conditions, the triple nfo exoA nth knockout strain significantly increased the amounts of adaptive his, met, and leu revertants produced by the B. subtilis YB955 parental strain. Of note, the number of stationary-phase-associated reversions in the his, met, and leu alleles produced by the nfo exoA nth strain was significantly decreased following disruption of polX. In contrast, during growth, the reversion rates in the three alleles tested were significantly increased in cells of the nfo exoA nth knockout strain deficient for polymerase X (PolX). Therefore, we postulate that adaptive mutations in B. subtilis can be generated through a novel mechanism mediated by error-prone processing of AP sites accumulated in the stationary phase by the PolX DNA polymerase.
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Which mechanisms underlie adaptive mutagenesis (stationary-phase mutagenesis) in Bacillus subtilis?
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subtilis can be generated through a novel mechanism mediated by error-prone processing of AP sites accumulated in the stationary phase by the PolX DNA polymerase
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Several second-generation active β-amyloid (Aβ) vaccines and passive Aβ immunotherapies are under clinical investigation with the aim of boosting Aβ clearance from the brain of the Alzheimer's disease (AD) patients. However, the preliminary cognitive efficacy of bapineuzumab, a humanized anti-Aβ monoclonal antibody, appears uncertain. Moreover, the occurrence of vasogenic edema and, more rarely, brain microhemorrhages, especially in apolipoprotein E ϵ4 carriers, have led to abandoning of the highest dose of the drug. Solanezumab, another humanized anti-Aβ monoclonal antibody, was shown to neutralize soluble Aβ oligomers, which is believed to be the more neurotoxic Aβ species. Phase II studies showed a good safety profile of solanezumab while studies on cerebrospinal and plasma biomarkers documented good signals of pharmacodynamic activity. However, the preliminary equivocal cognitive results obtained with bapineuzumab as well as the detrimental cognitive effects observed with semagacestat, a potent γ-secretase inhibitor, raise the possibility that targeting Aβ may not be clinically efficacious in AD. The results of four ongoing large Phase III trials on bapineuzumab and two Phase III trials on solanezumab will tell us if passive anti-Aβ immunization is able to alter the course of this devastating disease, and if Aβ is still a viable target for anti-AD drugs.
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Is bapineuzumab effective for treatment of patients with Alzheimer's disease?
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However, the preliminary equivocal cognitive results obtained with bapineuzumab as well as the detrimental cognitive effects observed with semagacestat, a potent γ-secretase inhibitor, raise the possibility that targeting Aβ may not be clinically efficacious in AD.
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Super-enhancers are characterized by high levels of Mediator binding and are major contributors to the expression of their associated genes. They exhibit high levels of local chromatin interactions and a higher order of local chromatin organization. On the other hand, lncRNAs can localize to specific DNA sites by forming a RNA:DNA:DNA triplex, which in turn can contribute to local chromatin organization. In this paper, we characterize a new class of lncRNAs called super-lncRNAs that target super-enhancers and which can contribute to the local chromatin organization of the super-enhancers. Using a logistic regression model based on the number of RNA:DNA:DNA triplex sites a lncRNA forms within the super-enhancer, we identify 442 unique super-lncRNA transcripts in 27 different human cell and tissue types; 70% of these super-lncRNAs were tissue restricted. They primarily harbor a single triplex-forming repeat domain, which forms an RNA:DNA:DNA triplex with multiple anchor DNA sites (originating from transposable elements) within the super-enhancers. Super-lncRNAs can be grouped into 17 different clusters based on the tissue or cell lines they target. Super-lncRNAs in a particular cluster share common short structural motifs and their corresponding super-enhancer targets are associated with gene ontology terms pertaining to the tissue or cell line. Super-lncRNAs may use these structural motifs to recruit and transport necessary regulators (such as transcription factors and Mediator complexes) to super-enhancers, influence chromatin organization, and act as spatial amplifiers for key tissue-specific genes associated with super-enhancers.
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Is Mediator present at super enhancers?
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Super-enhancers are characterized by high levels of Mediator binding and are major contributors to the expression of their associated genes.
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Epigenetic changes are defined as inherited modifications that are not present in DNA sequence. Gene expression is regulated at various levels and not only in response to DNA modifications. Examples of epigenetic control are DNA methylation, histone deacetylation and mi-RNA expression. Methylation of several tumor suppressor gene promoters is responsible for their silencing and thus potentially sustain cancerogenesis. Similarly, histone deacetylation can lead to oncogene activation. mi-RNA are small (18-20 nucleotides) non-coding RNA fragments capable of inhibiting other m-RNA, ultimately altering the balance in oncogene and tumor suppressor gene expression. It has been shown that growth of several tumor types can be stimulated by epigenetic changes in various phases of cancerogenesis, and drugs able to interfere with these mechanisms can have a positive impact on tumor progression. As matter of fact, epigenetic changes are dynamic and can be reversed by epigenetic inhibitors. Recently, methyltransferase and histone deacetylase inhibitors have attracted the attention of researchers and clinicians as they potentially provide alternative therapeutic options in some cancers. Drugs that inhibit DNA methylation or histone deacetylation have been studied for the reactivation of tumor suppressor genes and repression of cancer cell growth. Epigenetic inhibitors work alone or in combination with other therapeutic agents. To date, a number of epigenetic inhibitors have been approved for cancer treatment. The main challenge in the field of epigenetic inhibitors is their lack of specificity. In this review article we describe their mechanisms of action and potential in cancer treatment.
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What are some examples of epigenetic modifications?
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Epigenetic changes are defined as inherited modifications that are not present in DNA sequence.
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cause sudden cardiac death?
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Patients diagnosed with an electrical cardiomyopathy have an increased risk of syncope and sudden cardiac death (SCD).
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The pathology of drug-induced pulmonary toxicity in children is poorly understood and probably under-estimated, in the absence of any prospective studies evaluating in a systematic fashion the side effect of medication on the respiratory apparatus. The pulmonary toxicity of thoracic irradiation has markedly receded with more restricted indications for this sort of treatment. Three clinical patterns are most commonly encountered in drug induced lung disease in children: interstitial lung disease, hypersensitivity lung disease and non-cardiogenic pulmonary oedema. The diagnosis is a diagnosis of exclusion and rests on a group of clinical arguments and also on the progress of the disease. Broncho-alveolar lavage rules out infectious disease. Respiratory function tests show non-specific anomalies. A lung biopsy may be indicated. The mechanism of the pulmonary toxicity are associated with disequilibrium of the oxidant/antioxidant and protease/antiprotease system as well as disturbance of the immune response or alteration of the pulmonary matrix by disease of the collagen system. Increased toxicity may be seen in children because of a very significant cumulative dose. The cytotoxic drugs which are most often implicated in causing this are bleomycin, methotrexate, cyclophosphamide and busulfan. Other drugs which are responsible for toxic lung disease are nitrofurantoin, sulfasalazine, D-penicillamine, betalactams, Diphenyl-hydantoin and carbamazepine. Acute post-radiation lung disease is rare. Post-radiation fibrosis is found six months after irradiation and hinders thoraco-pulmonary growth in the child. It is important to assess lung function in all children before any chemotherapy or thoracic irradiation. Cytotoxic drugs are the most common cause of toxic lung disease. This iatrogenic disease requires a multi-discipline approach to ensure the quality of care for these children.
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What class of drugs is commonly associated with Drug-induced interstitial lung disease (DIILD)?
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Cytotoxic drugs are the most common cause of toxic lung disease.
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Mgm1 is a member of the dynamin family of GTP-binding proteins. Mgm1 was first identified in yeast, where it affects mitochondrial morphology. The human homologue of Mgm1 is called OPA1. Mutations in the OPA1 gene are the prevailing cause of dominant optic atrophy, a hereditary disease in which progressive degeneration of the optic nerve can lead to blindness. Here we investigate the properties of the Mgm1/OPA1 protein in mammalian cells. We find that Mgm1/OPA1 is localized to the mitochondrial intermembrane space, where it is tightly bound to the outer surface of the inner membrane. Overexpression of wild type or mutant forms of the Mgm1/OPA1 protein cause mitochondria to fragment and, in some cases, cluster near the nucleus, whereas the loss of protein caused by small interfering RNA (siRNA) leads to dispersal of mitochondrial fragments throughout the cytosol. The cristae of these fragmented mitochondria are disorganized. At early time points after transfection with Mgm1/OPA1 siRNA, the mitochondria are not yet fragmented. Instead, the mitochondria swell and stretch, after which they form localized constrictions similar to the mitochondrial abnormalities observed during the early stages of apoptosis. These abnormalities might be the earliest effects of losing Mgm1/OPA1 protein.
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Which is the cellular localization of the protein Opa1?
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We find that Mgm1/OPA1 is localized to the mitochondrial intermembrane space,
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Macrophage actin-associated tyrosine phosphorylated protein (MAYP) belongs to the Pombe Cdc15 homology (PCH) family of proteins involved in the regulation of actin-based functions including cell adhesion and motility. In mouse macrophages, MAYP is tyrosine phosphorylated after activation of the colony-stimulating factor-1 receptor (CSF-1R), which also induces actin reorganization, membrane ruffling, cell spreading, polarization, and migration. Because MAYP associates with F-actin, we investigated the function of MAYP in regulating actin organization in macrophages. Overexpression of MAYP decreased CSF-1-induced membrane ruffling and increased filopodia formation, motility and CSF-1-mediated chemotaxis. The opposite phenotype was observed with reduced expression of MAYP, indicating that MAYP is a negative regulator of CSF-1-induced membrane ruffling and positively regulates formation of filopodia and directional migration. Overexpression of MAYP led to a reduction in total macrophage F-actin content but was associated with increased actin bundling. Consistent with this, purified MAYP bundled F-actin and regulated its turnover in vitro. In addition, MAYP colocalized with cortical and filopodial F-actin in vivo. Because filopodia are postulated to increase directional motility by acting as environmental sensors, the MAYP-stimulated increase in directional movement may be at least partly explained by enhancement of filopodia formation.
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Which proteins are involved in actin bundling and filopodia formation and function?
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Overexpression of MAYP decreased CSF-1-induced membrane ruffling and increased filopodia formation, motility and CSF-1-mediated chemotaxis.
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The septins are filament-forming, GTP-binding proteins that are conserved from yeast to humans. Septins assemble into higher-order structures such as rings, bars, and gauzes with diverse functions including serving as membrane diffusion barriers and scaffolds for cell signaling. The basis for septin filament polymerization and the rules governing septin polymer dynamics are presently not well understood. Pharmacological agents are essential tools in studying such properties of the actin and microtubule cytoskeletons however there are only limited reports of a drug specific to the septin cytoskeleton. Forchlorfenuron (FCF) is a synthetic plant cytokinin used in agriculture which has been shown to alter septin organization in yeast and mammalian tissue culture cells. Here we assess cellular requirements and properties of septin-based structures induced by FCF. Treatment of the filamentous fungus Ashbya gossypii with FCF leads to assembly of extensive septin fibers throughout hyphae which is rapidly reversed upon removal of the drug. These fibers do not exchange or add septin subunits after assembly, indicating that FCF suppresses normal septin dynamics and stabilizes the polymers. While FCF-induced septin fibers do not co-localize to actin or microtubules, a polarized F-actin cytoskeleton is likely required for the assembly of drug-induced septin fibers. Thus, FCF is a potent inducer of septin polymerization and acts as a reversible stabilizer of extended septin polymers. This drug will be a powerful tool for studying mechanisms of septin polymerization and function, particularly in cell types where molecular analyses are complicated by the presence of multiple isoforms and limited genetics.
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What are Septins?
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The septins are filament-forming, GTP-binding proteins that are conserved from yeast to humans. Septins assemble into higher-order structures such as rings, bars, and gauzes with diverse functions including serving as membrane diffusion barriers and scaffolds for cell signaling.
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The members of the NOX family of enzymes are expressed in a variety of tissues and serve a number of functions. There is a high level of conservation of primary protein sequence, as well as functional features, although specialized responses are beginning to emerge. In this context, our data demonstrate that the NOX1 cytoplasmic domains interact efficiently with the cytoplasmic subunits of the phagocyte NADPH oxidase and identify the second cytoplasmic loop of NOX electron transporters as a crucial domain for enzyme function. Studies of cytosolic co-factors showed that the C-terminal cytoplasmic domain of NOX1 was absolutely required for activation with NOXO1 and NOXA1 and that this activity required interaction of the putative NADPH-binding region of this domain with NOXA1. Finally, we have provided the first example of how alternative splicing of a NOX co-factor may be involved in the regulation of NADPH oxidase function.
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Which NADPH oxidase family member requires interaction with NOXO1 for function?
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Studies of cytosolic co-factors showed that the C-terminal cytoplasmic domain of NOX1 was absolutely required for activation with NOXO1 and NOXA1 and that this activity required interaction of the putative NADPH-binding region of this domain with NOXA1.
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Fanconi anemia (FA) is a genetically heterogeneous autosomal recessive syndrome associated with chromosomal instability, hypersensitivity to DNA cross-linking agents, and predisposition to malignancy. The gene for FA complementation group G (FANCG) was the third FA gene to be cloned, and was found to be identical with human XRCC9, which maps to 9p13. The cDNA is predicted to encode a polypeptide of 622 amino acids, with no sequence similarities to any other known protein or motifs that could point to a molecular function for FANCG/XRCC9. We used single strand conformational polymorphism analysis (SSCP) to screen genomic DNA from a panel of 307 racially and ethnically diverse unrelated FA patients from the International Fanconi Anemia Registry (IFAR) for variants in FANCG. Twenty-seven abnormal SSCP patterns were found; 18 of these variants appear to be pathogenic mutations while nine are likely to be nonpathogenic polymorphisms. Direct sequencing of genomic DNA from seven FA-G probands with one mutant allele not detected in the SSCP study and three additional probands assigned to the FA-G complementation group by retroviral correction with FANCG resulted in the detection of nine additional pathogenic mutations and two common SNPs. Conditions for rapid screening for these mutations by DHPLC for use in a clinical laboratory setting were established. The most common FANCG mutations in the IFAR population were: IVS8-2A>G (seven Portuguese-Brazilian probands), IVS11+1G>C (seven French-Acadian probands), 1794_1803del10 (seven European probands), and IVS3+1G>C (five Korean or Japanese probands). Our data suggest that the Portuguese-Brazilian, French-Acadian, and Korean/Japanese mutations were likely to have been present in a founding member of each of these populations.
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Is Fanconi anemia presented as a genetically and clinically heterogeneous disease entity?
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Fanconi anemia (FA) is a genetically heterogeneous autosomal recessive syndrome associated with chromosomal instability, hypersensitivity to DNA cross-linking agents, and predisposition to malignancy
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The CHEK2-1100delC mutation is recurrent in the population and is a moderate risk factor for breast cancer. To identify additional CHEK2 mutations potentially contributing to breast cancer susceptibility, we sequenced 248 cases with early-onset disease; functionally characterized new variants and conducted a population-based case-control analysis to evaluate their contribution to breast cancer risk. We identified 1 additional null mutation and 5 missense variants in the germline of cancer patients. In vitro, the CHEK2-H143Y variant resulted in gross protein destabilization, while others had variable suppression of in vitro kinase activity using BRCA1 as a substrate. The germline CHEK2-1100delC mutation was present among 8/1,646 (0.5%) sporadic, 2/400 (0.5%) early-onset and 3/302 (1%) familial breast cancer cases, but undetectable amongst 2,105 multiethnic controls, including 633 from the US. CHEK2-positive breast cancer families also carried a deleterious BRCA1 mutation. 1100delC appears to be the only recurrent CHEK2 mutation associated with a potentially significant contribution to breast cancer risk in the general population. Another recurrent mutation with attenuated in vitro function, CHEK2-P85L, is not associated with increased breast cancer susceptibility, but exhibits a striking difference in frequency across populations with different ancestral histories. These observations illustrate the importance of genotyping ethnically diverse groups when assessing the impact of low-penetrance susceptibility alleles on population risk. Our findings highlight the notion that clinical testing for rare missense mutations within CHEK2 may have limited value in predicting breast cancer risk, but that testing for the 1100delC variant may be valuable in phenotypically- and geographically-selected populations.
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Which is the main CHEK2 genetic variant, thought to be involved in familial breast cancer?
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The CHEK2-1100delC mutation is recurrent in the population and is a moderate risk factor for breast cancer
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Patients with Sjögren syndrome are at increased risk of lymphoma development. Because most lymphomas initially involve the neck organs, including the lymph nodes, meticulous imaging studies mainly focused on the cervical regions are recommended in the follow-up of patients with Sjögren syndrome.
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Are patients with Sjogren syndrome at increased risk for lymphoma?
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Patients with Sjögren syndrome are at increased risk of lymphoma development.
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Teprotumumab (teprotumumab-trbw; TEPEZZA™ - Horizon Therapeutics) is a monoclonal antibody insulin-like growth factor-I receptor (IGF-IR) antagonist developed for the treatment of thyroid eye disease (Graves ophthalmopathy/orbitopathy, thyroid-associated ophthalmopathy). Based on positive results from two multinational clinical trials teprotumumab was recently approved for this indication in the US. This article summarizes the milestones in the development of teprotumumab leading to this first approval for thyroid eye disease.
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Which molecule is targeted by Teprotumumab?
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Teprotumumab (teprotumumab-trbw; TEPEZZA™ - Horizon Therapeutics) is a monoclonal antibody insulin-like growth factor-I receptor (IGF-IR) antagonist developed for the treatment of thyroid eye disease (Graves ophthalmopathy/orbitopathy, thyroid-associated ophthalmopathy).
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The leucine rich repeat kinase 2 (LRRK2/dardarin) is implicated in autosomal dominant familial and sporadic Parkinson's disease (PD); mutations in LRRK2 account for up to 40% of PD cases in some populations. LRRK2 is a large protein with a kinase domain, a GTPase domain, and multiple potential protein interaction domains. As such, delineating the functional pathways for LRRK2 and mechanisms by which PD-linked variants contribute to age-related neurodegeneration could result in pharmaceutically tractable therapies. A growing number of recent studies implicate dysregulation of mitogen activated protein kinases 3 and 1 (also known as ERK1/2) as possible downstream mediators of mutant LRRK2 effects. As these master regulators of growth, differentiation, neuronal plasticity and cell survival have also been implicated in other PD models, a set of common cell biological pathways may contribute to neuronal susceptibility in PD. Here, we review the literature on several major cellular pathways impacted by LRRK2 mutations--autophagy, microtubule/cytoskeletal dynamics, and protein synthesis--in context of potential signaling crosstalk involving the ERK1/2 and Wnt signaling pathways. Emerging implications for calcium homeostasis, mitochondrial biology and synaptic dysregulation are discussed in relation to LRRK2 interactions with other PD gene products. It has been shown that substantia nigra neurons in human PD and Lewy body dementia patients exhibit cytoplasmic accumulations of ERK1/2 in mitochondria, autophagosomes and bundles of intracellular fibrils. Both experimental and human tissue data implicate pathogenic changes in ERK1/2 signaling in sporadic, toxin-based and mutant LRRK2 settings, suggesting engagement of common cell biological pathways by divergent PD etiologies.
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What is the dardarin protein?
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The leucine rich repeat kinase 2 (LRRK2/dardarin) is implicated in autosomal dominant familial and sporadic Parkinson's disease (PD);
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Invasion of the subendothelial space by vascular smooth muscle cells (VSMCs) contributes to the development and progression of diverse cardiovascular diseases. In this report we show that the expression of activated versions of Src, Cdc42 and Rac1, or a kinase-dead but open form of the p21-activated kinase (PAK1), induces primary rat aorta VSMCs to form extracellular matrix-degrading actin-rich protrusions that are morphologically similar to the invadopodia formed by highly invasive tumor cells. The matrix-degrading structures are enriched in known markers for invadopodia, including cortactin and tyrosine-phosphorylated cortactin and contain the matrix metalloproteinases MMP-9 and MT1-MMP and the urokinase plasminogen activator receptor (uPAR). In contrast to other cell types, invadopodia formation in VSMCs is only weakly supported by the phorbol ester PBDu. Invadopodia formation by Src was dependent on Cdc42, Rac, and ERK, but not on p38 MAPK. Invadopodia formation induced by kinase-dead PAK1 required Src and ERK activity and a direct interaction with the exchange factor PIX. VSMCs embedded in a three-dimensional collagen matrix formed actin- and cortactin-rich extensions that penetrated through holes in the matrix, suggesting that invadopodia-like structures are formed in a three-dimensional environment.
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In which process Src, Cortactin and MT1-MMP are playing an essential role?
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In this report we show that the expression of activated versions of Src, Cdc42 and Rac1, or a kinase-dead but open form of the p21-activated kinase (PAK1), induces primary rat aorta VSMCs to form extracellular matrix-degrading actin-rich protrusions that are morphologically similar to the invadopodia formed by highly invasive tumor cells.
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Surgical or pharmacologic methods to control gonadal androgen biosynthesis are effective approaches in the treatment of a variety of non-neoplastic and neoplastic diseases. For example, androgen ablation and its consequent reduction in circulating levels of testosterone is an effective therapy for advanced prostate cancers. Unfortunately, the therapeutic effectiveness of this approach is often temporary because of disease progression to the 'castration resistant' (CRPC) state, a situation for which there are limited treatment options. One mechanism thought to be responsible for the development of CRPC is extra-gonadal androgen synthesis and the resulting impact of these residual extra-gonadal androgens on prostate tumor cell proliferation. An important enzyme responsible for the synthesis of extra-gonadal androgens is CYP17A1 which possesses both 17,20-lyase and 17-hydroxylase catalytic activities with the 17,20-lyase activity being key in the androgen biosynthetic process. Orteronel (TAK-700), a novel, selective, and potent inhibitor of 17,20-lyase is under development as a drug to inhibit androgen synthesis. In this study, we quantified the inhibitory activity and specificity of orteronel for testicular and adrenal androgen production by evaluating its effects on CYP17A1 enzymatic activity, steroid production in monkey adrenal cells and human adrenal tumor cells, and serum levels of dehydroepiandrosterone (DHEA), cortisol, and testosterone after oral dosing in castrated and intact male cynomolgus monkeys. We report that orteronel potently suppresses androgen production in monkey adrenal cells but only weakly suppresses corticosterone and aldosterone production; the IC(50) value of orteronel for cortisol was ~3-fold higher than that for DHEA. After single oral dosing, serum levels of DHEA, cortisol, and testosterone were rapidly suppressed in intact cynomolgus monkeys. In castrated monkeys treated twice daily with orteronel, suppression of DHEA and testosterone persisted throughout the treatment period. In both in vivo models and in agreement with our in vitro data, suppression of serum cortisol levels following oral dosing was less than that seen for DHEA. In terms of human CYP17A1 and human adrenal tumor cells, orteronel inhibited 17,20-lyase activity 5.4 times more potently than 17-hydroxylase activity in cell-free enzyme assays and DHEA production 27 times more potently than cortisol production in human adrenal tumor cells, suggesting greater specificity of inhibition between 17,20-lyase and 17-hydroxylase activities in humans vs monkeys. In summary, orteronel potently inhibited the 17,20-lyase activity of monkey and human CYP17A1 and reduced serum androgen levels in vivo in monkeys. These findings suggest that orteronel may be an effective therapeutic option for diseases where androgen suppression is critical, such as androgen sensitive and CRPC.
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Which enzyme is inhibited by Orteronel?
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Orteronel (TAK-700), a novel, selective, and potent inhibitor of 17,20-lyase is under development as a drug to inhibit androgen synthesis
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Delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage is a cause of considerable morbidity and mortality. Magnesium sulfate has been proposed as a prophylactic intervention for angiographic vasospasm and to improve clinical outcomes. A systematic review was conducted to determine the evidence for the prophylactic use of magnesium sulfate in aneurysmal subarachnoid hemorrhage. Medline, Embase, Cochrane library, clinicaltrials.gov, and controlled-trials.com were searched with a comprehensive search strategy. 2,035 records were identified in the initial search and 1,574 remained after removal of duplicates. Randomized, parallel group, controlled trials of magnesium sulfate in patients with aneurysmal subarachnoid hemorrhage were included. A total of ten studies were included. Review Manager and GRADE software were used to synthesize the results. The summary effect for Glasgow outcome scale and the modified Rankin scale is a risk ratio (RR) of 0.93 [95 % confidence interval (CI) 0.82-1.06]. The RR for mortality is 0.95 [95 % CI 0.76-1.17]. Delayed cerebral ischemia has a RR of 0.54 [95 % CI 0.38-0.75], which is the only outcome with a statistically significant summary effect measure favoring magnesium treatment. Delayed ischemic neurological deficit has a RR of 0.93 [95 % CI 0.62-1.39]. Transcranial doppler vasospasm has a RR of 0.72 [95 % CI 0.51-1.03]. Current evidence does not support the prophylactic use of magnesium sulfate in aneurysmal subarachnoid hemorrhage.
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Does magnesium sulfate improve outcomes of subarachnoid hemorrhage patients?
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Current evidence does not support the prophylactic use of magnesium sulfate in aneurysmal subarachnoid hemorrhage
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Most radiation-induced osteosarcomas of the skull are reported to arise in the facial bone or paranasal sinus after radiotherapy for retinoblastoma and/or pituitary adenoma. Here we report two cases of radiation-induced osteosarcoma in the paranasal sinus after treatment for frontal glioma. Case 1 was a 56-year-old woman who underwent surgical resection of a left frontal tumor in October 1990. The histological diagnosis was a low-grade glioma, and radiotherapy of 54 Gy was administered. Sixteen years later, in September 2006, the patient noted an enlarging subcutaneous mass in the right frontal region. CT showed an osteolytic mass in the right frontal sinus. An open biopsy established the histopathological diagnosis of osteosarcoma, and the patient subsequently died of rapid tumor regrowth. Case 2 was a 58-year-old man who underwent partial removal of a bifrontal tumor in May 1996. The histological diagnosis was anaplastic oligoastrocytoma, and radiotherapy of 56 Gy was administered. Twelve years later, in March 2008, the patient was readmitted to our hospital for reasons of marked deterioration in general physical condition. Tumor recurrence was suspected in the left frontal lobe, and CT demonstrated an osteolytic mass in the left frontal and ethmoid sinus. A secondary operation was performed, and the pathological specimens were diagnosed as osteosarcoma. Radiotherapy was readministered, but the subject died of rapid tumor regrowth. From these clinicopathological findings, both cases were diagnosed as radiation-induced osteosarcoma. Radiation-induced osteosarcomas appeared 16 and 12 years after radiotherapy in cases 1 and 2, respectively. As the prognosis of radiation-induced osteosarcoma is poorer than that of primary osteo-sarcoma, careful attention is required for consideration of the long-term survival of patients with glioma.
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Can radiotherapy cause radiation induced osteosarcoma?
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As the prognosis of radiation-induced osteosarcoma is poorer than that of primary osteo-sarcoma, careful attention is required for consideration of the long-term survival of patients with glioma.
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We sought to evaluate the efficacy and safety data of a combination regimen using weekly irinotecan in combination with capecitabine and concurrent radiotherapy (CapIri-RT) as neoadjuvant treatment in rectal cancer in a phase-II trial. Patients with rectal cancer clinical stages T3/4 Nx or N+ were recruited to receive irinotecan (50 mg m(-2) weekly) and capecitabine (500 mg m(-2) bid days 1-38) with a concurrent RT dose of 50.4 Gy. Surgery was scheduled 4-6 weeks after the completion of chemoradiation. A total of 36 patients (median age 62 years; m/f: 27:9) including three patients with local recurrence were enclosed onto the trial. The median distance of the tumour from the anal verge was 5 cm. The main toxicity observed was (NCI-CTC grades 1/2/3/4 (n)): Anaemia 23/9/-/-; leucocytopenia 12/7/7/2, diarrhoea 13/15/4/-, nausea/vomiting 9/10/2/-, and increased activity of transaminases 3/3/1/-. One patient had a reversible episode of ventricular fibrillation during chemoradiation, most probably caused by capecitabine. The relative dose intensity was (median/mean (%)): irinotecan 95/91, capecitabine 100/92). Thirty-four patients underwent surgery (anterior resection n=25; abdomino-perineal resection n=6; Hartmann's procedure n=3). R0-resection was accomplished in all patients. Two patients died in the postoperative course from septic complications. Pathological complete remission was observed in five out of 34 resected patients (15%), and nine patients showed microfoci of residual tumour (26%). After a median follow-up of 28 months one patient had developed a local recurrence, and five patients distant metastases. Three-year overall survival for all patients with surgery (excluding three patients treated for local relapse or with primary metastatic disease) was 80%. In summary, preoperative chemoradiation with CapIri-RT exhibits promising efficacy whereas showing managable toxicity. The local recurrence and distant failure rates observed after a median 28 months are low compared with standard 5-fluorouracil based therapy.
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Which drugs are included in the CAPIRI regimen?
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We sought to evaluate the efficacy and safety data of a combination regimen using weekly irinotecan in combination with capecitabine and concurrent radiotherapy (CapIri-RT) as neoadjuvant treatment in rectal cancer in a phase-II trial.
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Ras/Raf-prototypic oncogenes induce cellular senescence, a terminal cell-cycle arrest, as a default cellular safeguard program, while oncogenic Myc is known to rather promote apoptosis as the prime failsafe mechanism. We review and discuss here evidence for Myc-induced senescence - which is detectable to a limited degree as a cell-autonomous, direct response to Myc action, but occurs predominantly in a non-cell-autonomous fashion via crosstalk of the oncogene-driven cell population with non-neoplastic bystanders, namely cells of the host immune system, prompting them to release pro-senescent cytokines that strike back onto adjacent proliferating tumor cells. In particular, we discuss how Myc-evoked apoptosis serves as a signal for macrophage attraction and activation, followed by the secretion of TGF-β as a cytokine that is capable of terminally arresting Myc-driven lymphoma cells without causing further DNA damage and without launching a senescence-associated, pro-inflammatory, and, therefore, potentially detrimental cytokine response in the target population. In essence, non-cell-autonomous but still oncogene-orchestrated senescence is a functionally relevant, robustly tumor-suppressive principle with critical implications for conceptually novel anti-cancer therapies in the clinic.
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Which oncogenes are able to induce cellular senescence?
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Ras/Raf-prototypic oncogenes induce cellular senescence, a terminal cell-cycle arrest, as a default cellular safeguard program
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Miller Fisher syndrome is a variant of Guillain-Barre syndrome characterized by the classic triad of ophthalmoplegia, ataxia, and areflexia. Pupillary involvement is common in MFS and has been reported in 35-42% of MFS patients. Although case reports have discussed isolated ophthalmoplegia as a presentation of MFS, anisocoria and rapid fluctuation of pupillary diameter have not been reported in anti-GQ1b antibody positive individuals. Here we describe an individual who presented with diplopia and was found to have progressive internal and external ophthalmoplegia with frequent fluctuations in pupillary diameter and anisocoria. These exam findings are not commonly described even in atypical presentations of MFS. The onset of symptoms was preceded by an upper respiratory infection but no gastrointestinal symptoms. Imaging and CSF studies were unremarkable; however serum levels of immunoglobulin G anti-GQ1b antibody and anti-GAD antibody were elevated confirming the diagnosis of MFS. The patient was treated with IVIG and intravenous steroids with mild resolution of external ophthalmoplegia. He did not go on to develop more typical features of MFS such as ataxia or areflexia. This demonstrates that isolated external and internal ophthalmoparesis with rapidly fluctuating pupillary diameter and associated anisocoria can be the sole manifestation of atypical MFS.
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Is the Miller-Fisher syndrome considered to be a variant of Guillain-Barré?
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Miller Fisher syndrome is a variant of Guillain-Barre syndrome characterized by the classic triad of ophthalmoplegia, ataxia, and areflexia
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Pulmonary hypertension (PH) is a progressive disease that is accompanied by a poor prognosis. Pulmonary vasoconstriction is facilitated through multiple pathways and results in increased pulmonary vascular pressure leading to cell proliferation, vascular remodeling, right ventricular hypertrophy/failure, and ultimately death. Until recently, just six medications were approved -all for one subclass of PH. On October 8, 2013, riociguat (Adempas®) became the first medication approved for multiple etiologies of PH. Preclinical studies have demonstrated safety and efficacy with significant clinical trials supporting its advancement into phase IV trials. Although long-term safety and efficacy and place in therapy remain to be established, riociguat presents as an exciting new option for the treatment of PH and potentially has additional indications in the near future.
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What is generic name of drug Adempas?
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On October 8, 2013, riociguat (Adempas®) became the first medication approved for multiple etiologies of PH.
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An unexpectedly large fraction of genes in metazoans (human, mouse, zebrafish, worm, fruit fly) express high levels of circularized RNAs containing canonical exons. Here we report that circular RNA isoforms are found in diverse species whose most recent common ancestor existed more than one billion years ago: fungi (Schizosaccharomyces pombe and Saccharomyces cerevisiae), a plant (Arabidopsis thaliana), and protists (Plasmodium falciparum and Dictyostelium discoideum). For all species studied to date, including those in this report, only a small fraction of the theoretically possible circular RNA isoforms from a given gene are actually observed. Unlike metazoans, Arabidopsis, D. discoideum, P. falciparum, S. cerevisiae, and S. pombe have very short introns (∼ 100 nucleotides or shorter), yet they still produce circular RNAs. A minority of genes in S. pombe and P. falciparum have documented examples of canonical alternative splicing, making it unlikely that all circular RNAs are by-products of alternative splicing or 'piggyback' on signals used in alternative RNA processing. In S. pombe, the relative abundance of circular to linear transcript isoforms changed in a gene-specific pattern during nitrogen starvation. Circular RNA may be an ancient, conserved feature of eukaryotic gene expression programs.
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What is the function of circular RNA?
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Circular RNA may be an ancient, conserved feature of eukaryotic gene expression programs.
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This research paper examines the challenges in the development and adoption of an electronic patient diary within the Pathways Home for Respiratory Illness Project. This project supported community-based patients suffering from chronic obstructive pulmonary disease (COPD) to achieve increased levels of self-management and self-efficacy using electronic-monitoring techniques and mentoring by community health nurses. Participants had the option of voluntarily adopting an electronic patient diary to support their self-monitoring, which provided patients, nurses and clinicians with access to symptom and psycho-social data. This aimed to improve the identification, comprehension and initiation of early action in relation to alterations in their conditions. The paper presents data on technology adoption, electronic diary usage and, self-reported data quality, as well as examining the impact of the technology on hospitalisations (frequency and duration). The participants who chose to use the online patient diary continued their involvement with the project for the entire trial period (85% vs 54% completion). Participants were more likely to maintain use of the online patient diary than the paper diary. Both the groups experienced a positive improvement in their self-efficacy to self-manage their condition scores. The data highlight the problems implicit in some of the assumptions underpinning existing information systems models, especially in evaluating impact and the end-points presumed to be relevant in systems development life cycles.
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In which diseases have electronic patient diaries been applied ?
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This project supported community-based patients suffering from chronic obstructive pulmonary disease (COPD) to achieve increased levels of self-management and self-efficacy using electronic-monitoring techniques and mentoring by community health nurses.
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Coronavirus disease 2019 (COVID-19) has become a global pandemic. Previous studies showed that comorbidities in patients with COVID-19 are risk factors for adverse outcomes. This study aimed to clarify the association between nervous system diseases and severity or mortality in patients with COVID-19. We performed a systematic literature search of four electronic databases and included studies reporting the prevalence of nervous system diseases in COVID-19 patients with severe and non-severe disease or among survivors and non-survivors. The included studies were pooled into a meta-analysis to calculate the odds ratio (OR) with 95% confidence intervals (95%CI). We included 69 studies involving 17 879 patients. The nervous system diseases were associated with COVID-19 severity (OR = 3.19, 95%CI: 2.37 to 4.30, P < 0.001) and mortality (OR = 3.75, 95%CI: 2.68 to 5.25, P < 0.001). Specifically, compared with the patients without cerebrovascular disease, patients with cerebrovascular disease infected with COVID-19 had a higher risk of severity (OR = 3.10, 95%CI: 2.21 to 4.36, P < 0.001) and mortality (OR = 3.45, 95% CI: 2.46 to 4.84, P < 0.001). Stroke was associated with severe COVID-19 disease (OR = 1.95, 95%CI: 1.11 to 3.42, P = 0.020). No significant differences were found for the prevalence of epilepsy (OR = 1.00, 95%CI: 0.42 to 2.35, P = 0.994) and dementia (OR = 2.39, 95%CI: 0.55 to 10.48, P = 0.247) between non-severe and severe COVID-19 patients. There was no significant association between stroke (OR = 1.79, 95%CI: 0.76 to 4.23, P = 0.185), epilepsy (OR = 2.08, 95%CI: 0.08 to 50.91, P = 0.654) and COVID-19 mortality. In conclusion, nervous system diseases and cerebrovascular disease were associated with severity and mortality of patients with COVID-19. There might be confounding factors that influence the relationship between nervous system diseases and COVID-19 severity as well as mortality.
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What factors are associated with severe COVID-19?
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This study aimed to clarify the association between nervous system diseases and severity or mortality in patients with COVID-19.
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