title stringlengths 0 1.13k | abstract stringlengths 1 15.7k | PMID int64 22 36.5M |
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[Effect of VEGF165 and the VEGF aptamer pegaptanib (Macugen) on the protein composition of tight junctions in microvascular endothelial cells of the retina]. | VEGF signalling is deregulated in diabetic retinopathy. Therefore, VEGF inhibitors like the modified RNA-oligonucleotide pegaptanib (VEGF aptamer, Macugen) which inhibits the interaction of VEGF(165) with its receptors, are currently being discussed as therapeutic options in the treatment of diabetic retinopathy. VEGF(165) does not only stimulate the proliferation and migration of endothelial cells but also induces delocalization of occludin which is part of the so-called tight junctions of endothelial cells likely associated with the breakdown of the blood-retina barrier. To further investigate the mechanisms of action of VEGF and its inhibitor, we studied the influence of VEGF(165) and/or pegaptanib on the protein composition of tight junctions in immortalised endothelial cells of the bovine retina (iBREC) by immunofluorescence staining. The tight junction proteins ZO-1, occludin and claudin-5 are strongly expressed at the plasma membrane in confluent iBREC, but are located in the cytoplasm in non-confluent cells. In the presence of 50 ng/ml VEGF(165), occludin was found in the cytoplasm after 1 to 2 days, whereas claudin-5 was not and ZO-1 was only weakly influenced. However, after addition of 33 microg/ml pegaptanib for 24 h to VEGF(165)-treated iBREC, all tight junction proteins tested were again strongly expressed in the plasma membrane. These results confirm an important role of tight junction proteins in the mechanisms of action of VEGF and pegaptanib on endothelial cells. | 18,951,306 |
Cloning and expression of sheep DNA methyltransferase 1 and its development-specific isoform. | Unlike the mouse embryo, where loss of DNA methylation in the embryonic nucleus leaves cleavage stage embryos globally hypomethylated, sheep preimplantation embryos retain high levels of methylation until the blastocyst stage. We have cloned and sequenced sheep Dnmt1 and found it to be highly conserved with both the human and mouse homologues. Furthermore, we observed that the transcript normally expressed in adult somatic tissues is highly abundant in sheep oocytes. Throughout sheep preimplantation development the protein is retained in the cytoplasm whereas Dnmt1 transcript production declines after the embryonic genome activation at the 8-16 cell stage. Attempts to clone oocyte-specific 5' regions of Dnmt1, known to be present in the mouse and human gene, were unsuccessful. However, a novel ovine Dnmt1 exon, theoretically encoding 13 amino acids, was found to be expressed in sheep oocytes, preimplantation embryos and early fetal lineages, but not in the adult tissue. RNAi-mediated knockdown of this novel transcript resulted in embryonic developmental arrest at the late morula stage, suggesting an essential role for this isoform in sheep blastocyst formation. | 18,951,375 |
Influence of different assignment conditions on the determination of symmetric homodimeric structures with ARIA. | The ambiguous restraint for iterative assignment (ARIA) approach for NMR structure calculation is evaluated for symmetric homodimeric proteins by assessing the effect of several data analysis and assignment methods on the structure quality. In particular, we study the effects of network anchoring and spin-diffusion correction. The spin-diffusion correction improves the protein structure quality systematically, whereas network anchoring enhances the assignment efficiency by speeding up the convergence and coping with highly ambiguous data. For some homodimeric folds, network anchoring has been proved essential for unraveling both chain and proton assignment ambiguities. | 18,951,392 |
Evidence-based algorithms for diagnosing and treating ventilator-associated pneumonia. | Ventilator-associated pneumonia (VAP) is widely recognized as a serious and common complication associated with high morbidity and high costs. Given the complexity of caring for heterogeneous populations in the intensive care unit (ICU), however, there is still uncertainty regarding how to diagnose and manage VAP. We recently conducted a national collaborative aimed at reducing health care-associated infections in ICUs of hospitals operated by the Hospital Corporation of America (HCA). As part of this collaborative, we developed algorithms for diagnosing and treating VAP in mechanically ventilated patients. In the current article, we (1) review the current evidence for diagnosing VAP, (2) describe our approach for developing these algorithms, and (3) illustrate the utility of the diagnostic algorithms using clinical teaching cases. This was a descriptive study, using data from a national collaborative focused on reducing VAP and catheter-related bloodstream infections. The setting of the study was 110 ICUs at 61 HCA hospitals. None. We assembled an interdisciplinary team that included infectious disease specialists, intensivists, hospitalists, statisticians, critical care nurses, and pharmacists. After reviewing published studies and the Centers for Disease Control and Prevention VAP guidelines, the team iteratively discussed the evidence, achieved consensus, and ultimately developed these practical algorithms. The diagnostic algorithms address infant, pediatric, immunocompromised, and adult ICU patients. We present practical algorithms for diagnosing and managing VAP in mechanically ventilated patients. These algorithms may provide evidence-based real-time guidance to clinicians seeking a standardized approach to diagnosing and managing this challenging problem. | 18,951,395 |
Sense of coherence moderates late effects of early childhood Holocaust exposure. | This study evaluated child Holocaust survivors with an emphasis on potential protective factors facilitating participants' adaptation to post-Holocaust life. We examined Antonovsky's (1979, 1987) salutogenic paradigm, testing the mediating and moderating effect of participants' sense of coherence (SOC) on the association between early childhood deprivation due to Holocaust persecution and posttraumatic stress later in life. The nonclinical sample, composed of 203 child Holocaust survivors born between 1935 and 1944 completed questionnaires on Holocaust survival exposure, inventories on current health, posttraumatic stress, and SOC. The results indicated that SOC moderates the association between traumatic experiences during the war and posttraumatic stress, and SOC acts as a protective factor, buffering the impact of traumatic Holocaust experiences on child survivors in old age. Survivors with a less coherent perspective on the meaning of their life showed greater vulnerability for posttraumatic complaints. The moderating role of the SOC may suggest promising avenues of therapeutic interventions for child Holocaust survivors and other adults with early childhood trauma. | 18,951,426 |
Quantitative neurite outgrowth measurement based on image segmentation with topological dependence. | The study of neuronal morphology and neurite outgrowth has been enhanced by the combination of imaging informatics and high content screening, in which thousands of images are acquired using robotic fluorescent microscopy. To understand the process of neurite outgrowth in the context of neuroregeneration, we used mouse neuroblastoma N1E115 as our model neuronal cell. Six-thousand cellular images of four different culture conditions were acquired with two-channel widefield fluorescent microscopy. We developed a software package called NeuronCyto. It is a fully automatic solution for neurite length measurement and complexity analysis. A novel approach based on topological analysis is presented to segment cells. The detected nuclei were used as references to initialize the level set function. Merging and splitting of cells segments were prevented using dynamic watershed lines based on the constraint of topological dependence. A tracing algorithm was developed to automatically trace neurites and measure their lengths quantitatively on a cell-by-cell basis. NeuronCyto analyzes three important biologically relevant features, which are the length, branching complexity, and number of neurites. The application of NeuronCyto on the experiments of Toca-1 and serum starvation show that the transfection of Toca-1 cDNA induces longer neurites with more complexities than serum starvation. | 18,951,464 |
Cyclic neutropenia in mammals. | Cyclic neutropenia (CN) has been well documented in humans and the gray collie. A recent model of the architecture and dynamics of hematopoiesis has been used to provide insights into the mechanism of cycling of this disorder. It provides a link between the cycling period and the cells where the mutated ELA2 is expressed. Assuming that the biologic defect in CN is the same in dogs, and the observation that the structure of hematopoiesis is invariant across mammals, we use allometric scaling techniques to correctly predict the period of cycling in the gray collie and extend it to other mammals from mice to elephants. This work provides additional support for the relevance of animal models to understand disease but cautions that disease dynamics in model animals are different and this has to be taken into consideration when planning experiments. | 18,951,469 |
Modulation of microtubule dynamics by the microtubule-associated protein 1a. | Structural microtubule-associated proteins (MAPs) interact with microtubules to regulate the various dynamic stages of microtubules. The purpose of this study was to measure the impact of myc-tagged MAP1a fragments on microtubule dynamic phases in vivo. Cells from an epithelial kidney cell line (LLCPK1) that had been permanently transfected with human green fluorescent protein (GFP)-alpha-tubulin were transiently transfected with myc-tagged MAP1a fragments. Cells expressing MAP1a fragments were used to make direct observations of microtubule dynamics in living cells using fluorescence microscopy. All truncated MAP1a heavy chain fragments that contained the microtubule-binding domain were shown to associate with microtubules. Truncated fragments containing different regions of the projection domain of MAP1a demonstrated variations in their impact on microtubule dynamic events by promoting growth or inhibition of shortening phases. In contrast to MAP1a, MAP2c bundled microtubules and resulted in a complete arrest of microtubule motility. Results from the present study suggest that MAP1a promotes slow, stable growth of microtubules. This type of growth may be important in the maintenance and restructuring of adult neurons. | 18,951,470 |
Content of endoplasmic reticulum and Golgi complex membranes positively correlates with the proliferative status of brain cells. | Although the molecular and cellular basis of particular events that lead to the biogenesis of membranes in eukaryotic cells has been described in detail, understanding of the intrinsic complexity of the pleiotropic response by which a cell adjusts the overall activity of its endomembrane system to accomplish these requirements is limited. Here we carried out an immunocytochemical and biochemical examination of the content and quality of the endoplasmic reticulum (ER) and Golgi apparatus membranes in two in vivo situations characterized by a phase of active cell proliferation followed by a phase of declination in proliferation (rat brain tissue at early and late developmental stages) or by permanent active proliferation (gliomas and their most malignant manifestation, glioblastomas multiforme). It was found that, in highly proliferative phases of brain development (early embryo brain cells), the content of ER and Golgi apparatus membranes, measured as total lipid phosphorous content, is higher than in adult brain cells. In addition, the concentration of protein markers of ER and Golgi is also higher in early embryo brain cells and in human glioblastoma multiforme cells than in adult rat brain or in nonpathological human brain cells. Results suggest that the amount of endomembranes and the concentration of constituent functional proteins diminish as cells decline in their proliferative activity. | 18,951,474 |
Fate of the nasal capsular cartilages in prenatal and perinatal tamarins (Saguinus geoffroyi) and extent of secondary pneumatization of maxillary and frontal sinuses. | Development of the nasal capsule cartilages was studied in seven Geoffroy's tamarins (Saguinus geoffroyi), including one fetus, five neonates and one infant. Four additional postnatal specimens of the genus were studied (one 5-month-old and three adults) to determine the magnitude of postnatal expansion of the paranasal sinuses. Alcian blue histochemistry and osteopontin immunohistochemistry were employed in selected subadult specimens to characterize cartilage matrix. The fetal S. geoffroyi possesses a continuous nasal capsule, including a zona anularis; the primordial maxillary sinuses are surrounded by cartilage. Secondary pneumatization is in progress in all older specimens, which have sinuses that are more than twofold larger compared to that of the fetus. Results indicate that extensive ossification of the middle part of the nasal capsule (pars intermedia) is occurring in the perinatal timeframe, forming portions of the ethmoid bone. Anteriorly, the nasal capsule comprises isolated fragments in perinatal specimens, which are fewer and smaller in the infant and in a 5-month-old S. midas, and nearby multinucleate cells suggest that osteoclasts break apart these initially continuous elements. Fragments of the pars intermedia and the tectum nasi are found transiently between mucosa and the sites of secondary pneumatization. The maxillary sinus mucosa is highly vascular in most perinatal specimens. Histochemical and immunohistochemical findings show that cartilage of endochondral bones and non-ossifying parts are distinct in the perinatal time period. These results indicate that breakdown of the capsular cartilage precedes secondary pneumatization as previously suggested. There are portions of the cartilage of the recessus maxillaris and tectum nasi that transiently block mucosa from interfacing directly with bone. Vascularization may play a role in the breakdown of cartilages as well as the onset of secondary pneumatization. Since cartilage has the capacity to produce substances that trigger angiogenesis and bone resorption, further detailed characterization of the cartilage bordering sites of secondary pneumatization is merited. | 18,951,479 |
Spinal cord dysmyelination caused by an antiproteolipid protein IgM antibody: implications for the mechanism of central nervous system myelin formation. | Antiglycolipid IgM antibodies are known to induce formation of "wide spaced" or "expanded" myelin, a distinctive form of dysmyelination characterized by a repeat period approximately two or three times normal, which is seen also in diseases, including multiple sclerosis. To determine whether an antibody directed against a myelin protein would cause equivalent pathology, we implanted O10 hybridoma cells into the spinal cord of adult or juvenile rats. O10 produces an IgM directed against PLP, the major protein of CNS myelin. Subsequent examination of the cords showed focal demyelination and remyelination. In addition, however, some juvenile cords, but none of the adult cords, displayed wide-spaced myelin with lamellae separated by an extracellular material comprising elements consistent with IgM molecules in appearance. Wide spacing tended to involve the outer layers of the sheath and in some cases alternated with normally spaced lamellae. A feature not seen previously consists of multiple expanded myelin lamellae in one sector of a sheath continuous with normally spaced lamellae in another, resulting in variation in sheath thickness around the axonal circumference. This uneven distribution of wide-spaced lamellae is most simply explained based on incorporation of IgM molecules into immature sheaths during myelin formation and implies a model of CNS myelinogenesis more complex than simple spiraling. The periaxonal space never displays widening of this kind, but the interface with adjacent myelin sheaths or oligodendrocytes may. Thus, wide spacing appears to require that IgM molecules bridge between two PLP-containing membranes and does not reflect the mere presence of immunoglobulin within the extracellular space. | 18,951,490 |
Presence of the maxillary sinus in fossil Colobinae (Cercopithecoides williamsi) from South Africa. | Extant cercopithecoid monkeys, except macaques, are distinguished among primates by their lack of paranasal pneumatization, including the maxillary sinus (MS). Analysis of this structure, widespread among Eutheria, suggests that its loss occurred in the cercopithecoid common ancestor; thus, the presence of the MS in macaques is not strictly homologous to that in other primates. CT analysis of the fossil species Victoriapithecus macinnesi supports this view, demonstrating the lack of the MS in this stem cercopithecoid. Recent evidence, however, has documented the presence of the MS in extinct cercopithecoids from the late Miocene and Pliocene. This study reports on CT examination of two fossil crania attributed to Cercopithecoides williamsi from South Africa, dated in the range, 3.0-1.5 Ma. BF 42a is a complete cranium from Bolts Farm; MP113 is an intact facial skeleton, including the anterior cranial vault, from the Makapansgat Limeworks. Both demonstrate MS presence, unknown in extant colobines and unexpected in most cercopithecoid monkeys. The relative size of the MS of BF 42a is similar to that of extant tropical and subtropical macaques. The presence of sinuses in several extinct colobines suggests that our understanding of the evolutionary history of these primates, and of the MS, is incomplete, and that other fossil cercopithecoids should be examined for this feature. The developmental plasticity exhibited in this feature, indicated by multiple loss and reemergence, provides further evidence that paranasal pneumatization has undergone a complex history of suppression and expression. | 18,951,495 |
An automated self-similarity analysis of the pulmonary tree of the Sprague-Dawley rat. | We present the results of an automated analysis of the morphometry of the pulmonary airway trees of the Sprague-Dawley rat. Our work is motivated by a need to inform lower-dimensional mathematical models to prescribe realistic boundary conditions for multiscale hybrid models of rat lung mechanics. Silicone casts were made from three age-matched, male Sprague-Dawley rats, immersed in a gel containing a contrast agent and subsequently imaged with magnetic resonance (MR). From a segmentation of this data, we extracted a connected graph, representing the airway centerline. Segment statistics (lengths and diameters) were derived from this graph. To validate this MR imaging/digital analysis method, airway segment measurements were compared with nearly 1,000 measurements collected by hand using an optical microscope from one of the rat lung casts. To evaluate the reproducibility of the MR imaging/digital analysis method, two lung casts were each imaged three times with randomized orientations in the MR bore. Diameters and lengths of randomly selected airways were compared among each of the repeated imaging datasets to estimate the variability. Finally, we analyzed the morphometry of the airway tree by assembling individual airway segments into structures that span multiple generations, which we call branches. We show that branches not segments are the fundamental repeating unit in the rat lung and develop simple mathematical relationships describing these structures for the entire lung. Our analysis shows that airway diameters and lengths have both a deterministic and stochastic character. | 18,951,511 |
The estrous cycle modulates small leucine-rich proteoglycans expression in mouse uterine tissues. | In the pregnant mouse uterus, small leucine-rich proteoglycans (SLRPs) are drastically remodeled within a few hours after fertilization, suggesting that ovarian hormone levels modulate their synthesis and degradation. In this study, we followed by immunoperoxidase approach, the presence of four members of the SLRP family (decorin, lumican, biglycan, and fibromodulin) in the uterine tissues along the estrous cycle of the mouse. All molecules except fibromodulin, which predominates in the myometrium, showed a striking modulation in their distribution in the endometrial stroma, following the rise in the level of estrogen. Moreover, notable differences in the distribution of SLRPs were observed between superficial and deep stroma, as well as between the internal and external layers of the myometrium. Only biglycan and fibromodulin were expressed in the luminal and glandular epithelia. All four SLRPs were found in cytoplasmic granules of mononucleated cells. The pattern of distribution of the immunoreaction for these molecules in the uterine tissues was found to be estrous cycle-stage dependent, suggesting that these molecules undergo ovarian hormonal control and probably participate in the preparation of the uterus for decidualization and embryo implantation. In addition, this and previous results from our laboratory suggest the existence of two subpopulations of endometrial fibroblasts that may be related to the centrifugal development of the decidua. Anat Rec, 2008. (c) 2008 Wiley-Liss, Inc. | 18,951,514 |
Impact of changes in life circumstances on subjective well-being in an adult population over a 3-year period. | Mental health problems are a major issue worldwide, and there is a need to further explore factors that may increase or decrease people's subjective well-being (SWB). The main aim of the present study was to extend knowledge concerning changes in cohabitation, social support or financial situation and their influence on SWB, after controlling for personality (i.e. neuroticism), in a 3-year follow-up of an adult population-based sample. The change in overall well-being was also studied during the 3- year interval. Longitudinal design. A random sample of Swedish citizens, aged 20-64 years, residing in Stockholm County received a questionnaire by post, comprising items pertaining to demographics, personality, social support and SWB. All the respondents received a second questionnaire 3 years later. In total, 8324 subjects were included in the present study. The overall well-being of the study sample was relatively stable. Separate analyses of the three life circumstances indicated that, after controlling for personality, positive and negative changes in each sphere of life still affected SWB. Despite personality and the stability of SWB, these results indicate that changes in financial situation, social support and cohabitation influence SWB. It is important for society and the healthcare services to be aware that a negative change in any of these life circumstances may lead to decreased well-being for a period of at least 3 years. | 18,951,593 |
Clinical and molecular profile of a new series of patients with immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome: inconsistent correlation between forkhead box protein 3 expression and disease severity. | Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is an autoimmune genetic disorder caused by mutation of the forkhead box protein 3 gene (FOXP3), a key regulator of immune tolerance. We sought to provide clinical and molecular indicators that facilitate the understanding and diagnosis of IPEX syndrome. In 14 unrelated affected male subjects who were given diagnoses of IPEX syndrome based on FOXP3 gene sequencing, we determined whether particular FOXP3 mutations affected FOXP3 protein expression and correlated the molecular and clinical data. Molecular analysis of FOXP3 in the 14 subjects revealed 13 missense and splice-site mutations, including 7 novel mutations. Enteropathy, generally associated with endocrinopathy and eczema, was reported in all patients, particularly in those carrying mutations within FOXP3 functional domains or mutations that altered protein expression. However, similar genotypes did not always result in similar phenotypes in terms of disease presentation and severity. In addition, FOXP3 protein expression did not correlate with disease severity. Severe autoimmune enteropathy, which is often associated with increased IgE levels and eosinophilia, is the most prominent early manifestation of IPEX syndrome. Nevertheless, the disease course is variable and somewhat unpredictable. Therefore genetic analysis of FOXP3 should always be performed to ensure an accurate diagnosis, and FOXP3 protein expression analysis should not be the only diagnostic tool for IPEX syndrome. | 18,951,619 |
Neuro-archaeology: pre-symptomatic architecture and signature of neurological disorders. | During brain development cells divide, differentiate and migrate to their assigned targets to form synapses and active cell assemblies. This sequence is controlled both by genetic programs and environmental factors. Alterations of this sequence by mutations or environmental insults leads to the formation of misconnected circuits endowed with a 'pre-symptomatic signature'. I propose here that early- and late-onset neurological disorders as diverse as infantile epilepsies, mental retardation, dyslexia or, in certain conditions, even Huntington's and Alzheimer's disease might be, in part, born at early developmental stages before symptoms appear. The core of this working hypothesis is that imaging or non-invasive recordings might unravel signatures of disorders to come, thereby permitting earlier diagnosis and potential treatment of neurological disorders. | 18,951,639 |
Dynamic feedback between phenotype and physiology in sexually selected traits. | Theory predicts that physiological costs of producing elaborate phenotypes assure the honesty of sexually selected traits. It is generally assumed that these physiological processes drive sexually selected displays. However, a recent study by Safran and colleagues demonstrates that the manipulation of plumage ornaments in barn swallows alters the temporal course of circulating androgens, thus rejecting the scenario of a static, unidirectional relationship between physiology and sexual displays. Instead, these results suggest that dynamic feedbacks between physiological, morphological and behavioural costs underlie the development and maintenance of sexually selected ornaments. | 18,951,654 |
Spontaneous gasping increases cerebral blood flow during untreated fatal hemorrhagic shock. | Gasping has been found to be associated with improved ventilation, stroke volume, and cerebral blood flow (CBF) during untreated ventricular fibrillation. However, its effects have not been thoroughly assessed during fatal hemorrhagic shock. In this study, we hypothesized that gasping increases CBF during fatal hemorrhagic shock. Ten male Wistar rats (body weight: 195-225g) were intraperitoneally anesthetized with sodium pentobarbital (50mg/kg). Arterial pressure was recorded in the left femoral artery. Respiratory thoracic movements were recorded with a pressure sensor placed under the animal's back. The left carotid artery was cannulated to continuously withdraw blood (0.1ml/min) as a means of inducing hemorrhagic shock. CBF was measured with a laser flow meter. The arterial pulse wave was lost after withdrawing 7.3+/-0.9ml of blood and at that point, spontaneous gasping developed in all of the animals. CBF averaged 48.8+/-8.8ml/(min100g-brain) under control conditions before the start of blood withdrawal, and it decreased significantly to 4.4% of baseline during the pulseless state (P<0.01). The gasping, observed during in the pulseless state increased CBF to an average of 54.2% of baseline (P<0.01). Gasping was observed during fatal hemorrhagic shock and generated large increases in CBF. The forceful contraction of the inspiratory muscles during gasping may increase CBF by decreasing intrathoracic pressure, which increases venous return to the heart. | 18,951,685 |
Nitric oxide as an early marker of human embryo metabolic cleavage in ART using fresh or thawed oocytes. | To study a possible role of nitric oxide (NO) as a marker of development in the early phases of human embryo cleavage during assisted reproduction. 179 women having ART were included. 123 women used fresh oocytes and 56 oocyte thawing cycles in the Center of Reproductive Medicine, Department of Obstetrics and Gynecology, Arcispedale S. Maria Nuova, between July 2005 and June 2006; 57 patients had IVF and 122 patients had ICSI. NO concentrations in IVF or ICSI embryo culture media were assessed by monitoring levels of NO stable oxidation products (nitrites/nitrates). Analysis of embryo quality was performed. Student's t-test or Mann-Whitney and logistic regression model tests were applied to the data. In patients using fresh oocytes, there were greater NO production in embryos derived from ICSI than from IVF after 52 h of culture (38.64 micromol/L vs 11.2 micromol/L, p<0.05). No correlation with embryo quality was observed. Embryos derived from fresh oocytes produce more NO than embryos from thawed oocytes both after 48 and 52 h of culture (16.12 micromol/L vs 6.83 micromol/L and 25.93 micromol/L vs 2.98 micromol/L respectively, p<0.05). NO in embryo culture media is not a metabolic cleavage marker or a marker of embryo quality in ART. However, it could be an important parameter in the investigation of metabolism in frozen/thawed oocytes. | 18,951,688 |
Exchange of angular momentum in EMCD experiments. | In energy loss magnetic chiral dichroism (EMCD) experiments a chiral electronic transition is induced that obeys the dipole selection rule for the magnetic quantum number Deltam = +/- 1 or DeltaL(z) = +/- h. The incident plane electron wave is inelastically scattered and is detected in the diffraction plane, i.e. again in a plane wave state. Naïve reasoning suggests that the angular momentum L(z) of the probe electron has not changed in the interaction since plane waves have L(z) = 0. This leads to the seeming contradiction that angular momentum is not conserved in the interaction. A closer inspection shows that the density matrix of the probe has indeed L(z) = +/- h after a chiral interaction. However, L(z) is not conserved when the probe electron propagates further to the exit surface of the specimen because the rigid lattice breaks rotational symmetry. Thus, the angular momentum of the photo electron that is created in a chiral electronic transition stems from both the probing electron and the crystal lattice. | 18,951,701 |
Emerging treatment strategies for acute myeloid leukemia (AML) in the elderly. | Acute myeloid leukemia (AML) is more prevalent in older adults, with an incidence in the United States of 17.6 per 100,000 for those 65 years of age, compared with an incidence of 1.8 per 100,000 for those <65 years of age. While there have been improvements in survival during the last decade for younger patients, prognosis in elderly patients is still poor; approximately 50% achieve complete responses, but many of them relapse. With increasing age, more patients are suboptimal candidates for standard induction chemotherapy due to poor performance status, pre-existing myelodysplasia, unfavorable cytogenetics, treatment-related AML, multidrug resistance protein expression, and CD34 positivity, which are often characteristic of this patient population. In addition, the presence of comorbid conditions make many treatment options less tolerable for elderly patients. Several investigators have described subgroups showing no benefit after intensive treatment approaches in recent years. However, several novel agents have been developed to treat elderly AML patients. These include new chemotherapeutic agents, such as nucleoside analogs, as well as targeted therapies like farnesyltransferase inhibitors, tyrosine kinase inhibitors, epigenetic drugs, and antibodies. On the other hand new insights into the biology of the disease lead to a better understanding of its heterogeneity. Thus, with a variety of novel substances at hand it is increasingly important to introduce a risk-adapted approach for the optimal management of patients. This review will identify subgroups not likely to benefit from intensive chemotherapy and highlight the efficacy and tolerability of new agents in the treatment of AML. | 18,951,721 |
Involvement of CRH-R2 receptor in eating behavior and in the response of the HPT axis in rats subjected to dehydration-induced anorexia. | Wistar rats subjected to dehydration-induced anorexia (DIA), with 2.5% NaCl solution as drinking water for 7 days, decrease by 80% their food intake and present some changes common to pair-fed food restricted rats (FFR) such as: weight loss, decreased serum leptin and expression of orexigenic arcuate peptides, increasing the anorexigenic ones and serum corticosterone levels. In contrast, the response of the HPT axis differs: DIA animals have increased TRH expression in PVN and present primary as opposed to the tertiary hypothyroidism of the FFR. Exclusive to DIA is the activation of CRHergic neurons in the lateral hypothalamus (LH) that project to PVN. Since TRH neurons of the PVN contain CRH receptors, we hypothesized that the differences in the response of the HPT axis to DIA could be due to CRH regulating TRHergic neurons. CRH effect was first evaluated on TRH expression of cultured hypothalamic cells where TRH mRNA levels increased after 1h with 0.1nM of CRH. We then measured the mRNA levels of CRH receptors in the PVN of male and female rats subjected to DIA; only those of CRH-R2 were modulated (down-regulated). The CRH-R2 antagonist antisauvagine-30 was therefore injected into the PVN of male rats, during the 7 days of DIA. Antisauvagine-30 induced a higher food intake than controls, and impeded the changes produced by DIA on the HPT axis: PVN TRH mRNA, and serum TH and TSH levels were decreased to similar values of FFR animals. Results corroborate the anorexigenic effect of CRH and show its role, acting through CRH-R2 receptors, in the activation of TRHergic PVN neurons caused by DIA. These new data further supports clinical trials with CRH-R2 antagonists in anorexia nervosa patients. | 18,951,722 |
Local delivery of osteoprotegerin may be a way of reinforcing orthodontic anchorage. | One of the most challenging problems in orthodontics is anchorage. The traditional mechanical methods of reinforcing anchorage are limited by multiple factors, but a pharmacological approach aimed at utilizing the known biological mechanisms underlying tooth movement may provide an ideal way of reinforcing orthodontic anchorage. So we make the hypotheses that if the resorptive process of modeling during tooth movement can be inhibited, tooth movement may be inhibited as well. Since osteoprotegerin (OPG) has been found to be a key factor in the inhibition of osteoclast differentiation and activation, and involved in mechano-modulation of bone modeling, its local delivery adjacent to the anchorage teeth may provide a novel pharmacological approach for preventing unneeded tooth movement that is highly desirable for reinforcing orthodontic anchorage. | 18,951,727 |
Validation of a method for the determination of sterols and triterpenes in the aerial part of Justicia anselliana (Nees) T. Anders by capillary gas chromatography. | An accurate and sensitive method, combining soxhlet extraction, solid phase-extraction and capillary gas chromatography is described for the quantitative determination of one triterpene (lupeol) and three sterols (stigmasterol, campesterol and beta-sitosterol) and the detection of another triterpene (alpha-amyrin) from the aerial part of Justicia anselliana. This is the first method allowing the quantification of sterols and triterpenes in this plant. It has been fully validated in order to be able to compare the sterol and triterpene composition of different samples of J. anselliana and therefore help to explain the allelopathic activity due to these compounds. This method showed that the aerial part of J. anselliana contained (292+/-2)mg/kg of lupeol, (206+/-1)mg/kg of stigmasterol, (266+/-2)mg/kg of campesterol and (184+/-9)mg/kg of beta-sitosterol. | 18,951,746 |
[Field 5. Safety practices procedures for mechanical ventilation. French-speaking Society of Intensive Care. French Society of Anesthesia and Resuscitation]. | Invasive or endotracheal mechanical ventilation can lead to numerous complications likely to burden morbidity and mortality of patients in the intensive care unit. Various safety practices for mechanical ventilation may involve intubation, the mechanical ventilation period, weaning and extubation, the use of tracheostomy as well as non-invasive ventilation. The main objective of safety practices described in this chapter is to prevent or avoid the main risks due to invasive mechanical ventilation. | 18,951,756 |
[New autoanti-bodies in rheumatoid arthritis: anti-citrullinated protein or peptide autoanti-bodies and the others]. | New treatment strategies require that rheumatoid arthritis (RA) be diagnosed as early as possible. New diagnostic markers were required, because rheumatoid factors (RF), until now criteria for classification of RA, are not sufficiently specific and sometimes appear late, thereby limiting their diagnostic usefulness. The objective of this review is to describe the current state of knowledge and more particularly to analyze the interest of new RA autoanti-bodies, called anti-peptide or anti-citrullinated protein anti-bodies (ACPA). Other autoanti-bodies have been described, including anti-Sa, anti-alpha enolase, and anti-calpastatin autoanti-bodies. Nonetheless, their diagnostic value remains limited compared to ACPA. Accordingly, in daily practice today, the only autoanti-bodies that must be tested for to diagnose RA are the ACPAs and RFs. The discovery of ACPA (initially called anti-keratin and anti-perinuclear anti-bodies) was a major step forward for the laboratory diagnosis of RA. The tests most often used routinely areenzyme-linked immunosorbent assays(ELISA) with cyclic citrullinated peptides, whence the name anti-CCP autoanti-bodies. Accordingly, the two terms ACPA and anti-CCP can both be used. The diagnostic value, in particular their specificity, is on the order of 95%, regardless of the method of identification. These markers are very useful and are often present earlier than RF. These ACPA also have prognostic value because they are associated with more aggressive forms of RA. On the other hand, their value over time, in particular, their fluctuation as a function of treatment, is more controversial. In practice, it is recommended to test for both RF and ACPA in a diagnostic work-up for early RA. During follow-up, the value of testing for these autoanti-bodies has not been demonstrated, but additional studies are still necessary with the anti-CCP autoanti-bodies and the new anti-citrullinated protein autoanti-bodies. | 18,951,757 |
Total synthesis and biological evaluation of potent analogues of dictyostatin: modification of the C2-C6 dienoate region. | By exploiting a Still-Gennari olefination of a common C11-C26 aldehyde with a C4-C10 or C1-C10 beta-ketophosphonate, three modified C2-C6 region analogues of the 22-membered macrolide dictyostatin were synthesised and evaluated in vitro for growth inhibition against a range of human cancer cell lines, including the Taxol-resistant NCI/ADR-Res cell line. 6-Desmethyldictyostatin and 2,3-dihydrodictyostatin displayed potent (low nanomolar) antiproliferative activity, intermediate between dictyostatin and discodermolide, while 2,3,4,5-tetrahydrodictyostatin showed activity comparable to discodermolide. As with dictyostatin, these simplified analogues act through a mechanism of microtubule stabilisation, G2/M arrest and apoptosis. | 18,951,787 |
The contribution of plukenetione A to the anti-tumoral activity of Cuban propolis. | Increasing efforts are directed toward finding applications for natural products and their derivatives in the treatment of human diseases. Among such products, propolis, a resinous substance produced by honey bees from various plant sources, has been found to be a promising source of potential therapeutics. In the present work, we aimed at studying the perspective of Cuban propolis as a source of possible anti-cancer agents. We found an anti-metastatic effect in mice and considerable cytotoxicity without cross-resistance in both wild-type and chemoresistant human tumor cell lines. Plukenetione A--identified for the first time in Cuban propolis--induced G0/G1 arrest and DNA fragmentation in colon carcinoma cells. Furthermore, the activities of both topoisomerase I and DNA polymerase were inhibited, while the expression of topoisomerase II-beta, EGF receptor, and multidrug resistance-related protein genes was found repressed. We assume that plukenetione A contributes to the anti-tumoral effect of Cuban propolis mainly by targeting topoisomerase I as well as DNA polymerase. | 18,951,805 |
Periodontal impact of surgically induced dental lesions in mandibular osteodistraction: an animal study. | The objective of the study was to evaluate the impact of dental lesions on the periodontium, in a canine model of mandibular osteodistraction. In six adult male Beagle dogs, an osteotomy was made between the right second lateral incisor and canine, and a distraction device placed. The roots adjacent to the osteotomy were deliberately damaged by the reciprocating saw and chisel, with preservation of the attached gingiva. The osteodistraction protocol used was: latency of 7 days, rate of distraction 1mm per day, and rhythm once a day for 5 days. Vital staining was carried out with tetracycline, Xylenol Orange and Calcein Green. The dogs were sacrificed after 12 weeks of consolidation and the specimens were evaluated with light microscopy (native, polarized light, fluorescence, and after toluidin blue staining). The periodontal ligament (PDL) regeneration was observed in the 2500 slices examined. Cementum and dentine lesions were repaired by cellular cementum. Loose dentine and cementum-dentine fragments were embedded in regenerated PDL and their surface repaired by cementum. By means of light microscopic examination and within the limited observation time, no degenerative pulpal changes were found, when the pulp canal was not entered. Extensive pulp exposure and destruction resulted in ingrowth of the PDL and bone-like tissue. In that case, cellular cementum also lined the dentine surface of the pulp canal. Although there was an extensive reparative response to the para-pulpal lesions, none of the changes observed showed evidence of a loss of functional integrity of the periodontium at the distraction site. The fate of the tooth with exposed pulp canal remains uncertain. | 18,951,812 |
[The Vitruvian Man: an anatomical drawing for proportions by Leonardo Da Vinci]. | The aim of the study was to find out and to analyse the text by Vitruvius which inspired the famous drawing by Leonardo da Vinci (circa 1490) kept in the Galleria dell'Accademia, in Venezia, Italy: the man inscribed in one circle and in one square. The book "de Architectura" by Vitruvius Marcus Pollio was printed several times since the Renaissance when both the roman architecture of antiquity and this text became very popular. From a French translation by Claude Perrault in 1864, it became easy to find a French translation with the original text in Latin (Paris, 2003, Les Belles Lettres, French text by Pierre Gros). The drawing by Leonardo da Vinci illustrates with great accuracy and fidelity the quotation of Vitruvius (with the exception of two of the 12 main relationships). The genius of Leonardo da Vinci was to keep only one trunk, head and neck for two pairs of limbs: scapular and pelvic; to make the circle tangent to the lower edge of the square; to adjust a few features of the quotation for the equilibrium of the whole figure; and of course to bring his incredible skill as a drawer (one of the best of his century). The drawing was made on a sheet of paper 344x245mm, in black ink which became dark brown with time; several lines complete the figure above and below; a short caption and a horizontal scale appear just under the drawing. The celebrity of the drawing, a symbol of the Renaissance, of the equilibrium of man and mankind, of the universality of the artists and intellectuals of the time (Humanism) made it iconic and it has been constantly reproduced and adapted especially for advertisement and logos, not only in the medical field. | 18,951,824 |
Budget impact model of rituximab after failure of one or more TNFalpha inhibitor therapies in the treatment of rheumatoid arthritis. | To estimate the budget impact implied by the introduction of rituximab after failure of one or more anti-TNFalpha therapies in the perspective of the French health care system. A Markov model reproduced the course, over 4years, of patients treated either by infliximab, etanercept, adalimumab or RTX, after failure of one or more anti-TNFalpha therapies, in a multicentric study. A sensitivity analysis was developed to account for patients in 3rd and subsequent lines of treatment who are expected to consume more healthcare resources. When RTX is not used, total annual medical cost is euro16,555 per patient, euro13,206 of which are dedicated to drug acquisition. When RTX is the only treatment in use, these costs decrease respectively to euro11,444 and euro7469. Total savings per patient and per year is euro5000. Over 4 years, total savings for the targeted population reach euro118M. In the sensitivity analysis, the difference between H2 and H2-coeff 2 (20%) reaches euro5,400,000 in total direct costs during the first year of simulation. This difference decreases along the period, to reach euro2,400,000 the fourth year of simulation, and is due to the fact that rituximab acquisition costs are independent from the treatment line. If TNFalpha inhibitors were the only treatment available, the annual global cost of treatment would be euro16,555 per patient versus euro11,444 for patients treated exclusively with rituximab. RTX is expected to produce important savings (-31%) if used after failure of one or more TNFalpha therapies. This is mainly due to its lower drug acquisition cost. These savings could increase with the development of rituximab in earlier stages of treatment. | 18,951,825 |
Formin' an invasion machine: actin polymerization in invading apicomplexans. | Apicomplexan parasites are motile and invade host cells. The force required for this is generated by an actomyosin motor. In a recent paper, Baum and colleagues suggest that the protein formin regulates the polymerization of actin at the moving junction between parasite and host cell. This finding provides novel insight into the mechanism of host cell invasion. | 18,951,846 |
Injectable fillers for facial rejuvenation: a review. | Health care practices are moving toward a more preventative focus. In addition to leading healthier lives and seeking help to eradicate disease, patients are enlisting the help of plastic surgeons to reduce the visible signs of aging. Traditionally, facial rejuvenation focused on skin tightening through resection and resurfacing. In recent years, increasing emphasis has been placed on minimally invasive cosmetic improvement. Today, plastic surgeons combat the effects of aging with a variety of non-incisional methods such as soft-tissue augmentation with facial fillers. A multitude of soft-tissue fillers exist, each with their own chemical constituents, indications, and effectiveness. It is imperative that plastic surgeons understand these agents when treating patients with cosmetic complaints. | 18,951,862 |
Identification of an inducible factor secreted by pancreatic cancer cell lines that stimulates the production of fucosylated haptoglobin in hepatoma cells. | Fucosylation is one of the most important oligosaccharide modifications and is involved in cancer and inflammation. Recently, fucosylated haptoglobin was identified as a possible tumor marker for pancreatic cancer. The molecular mechanism underlying increases in fucosylated haptoglobin in sera of patients with pancreatic cancer seems to be complicated. Our previous study [N. Okuyama, Y. Ide, M. Nakano, T. Nakagawa, K. Yamanaka, K. Moriwaki, K. Murata, H. Ohigashi, S. Yokoyama, H. Eguchi, O. Ishikawa, T. Ito, M. Kato, A. Kasahara, S. Kawano, J. Gu, N. Taniguchi, E. Miyoshi, Fucosylated haptoglobin is a novel marker for pancreatic cancer: a detailed analysis of the oligosaccharide structure and a possible mechanism for fucosylation, Int. J. Cancer 118 (11) (2006) 2803-2808] demonstrated that pancreatic cancer cells secrete a factor, which induces the production of haptoglobin in hepatoma cells. In the present study, we found that interleukin 6 (IL6) expressed in pancreatic cancer is a factor that induces the haptoglobin production, using a neutralizing antibody for IL6. Real-time PCR analyses revealed the up-regulation of fucosylation regulatory genes after IL6 treatment, resulting increases in fucosylated haptoglobin being revealed by a lectin ELISA. This pathway could be one of the possible mechanisms underlying increases in haptoglobin in sera of patients with pancreatic cancer. | 18,951,869 |
Insulin gene is a target in activin receptor-like kinase 7 signaling pathway in pancreatic beta-cells. | Activins regulate pancreatic development, differentiation and insulin secretion. Activin receptor-like kinase 7 (ALK7) has been identified as a receptor for Nodal and Activin AB and B, and is expressed in pancreatic islets and beta-cell lines. In this study, human insulin promoter was activated by Smad2, Smad3 and the pancreatic and duodenal homeobox factor-1 (PDX-1) in the ALK7 pathway. A conserved Smad binding element was related to the promoter activation. Phosphorylated Smad2/Smad3 and PDX-1 were bound to insulin gene with Nodal and Activin AB, and the phosphorylated Smad2/Smad3 interacted with PDX-1. These results indicate that one of the direct target genes of Nodal and Activin AB signals is the insulin gene in pancreatic beta-cells and that PDX-1 is directly involved in the ALK7-Smad pathway. | 18,951,876 |
Allosteric modulation of 5-HT(1A) receptors by zinc: Binding studies. | 5-HT(1A) receptors were studied via [(3)H]WAY-100635 and [(3)H]8-OH-DPAT binding to rat brain cortical membranes. We characterized the effect of zinc (Zn(2+)) on the binding properties of the 5-HT(1A) receptor. The allosteric ternary complex model was applied to determine the dissociation constant (K(A)) of Zn(2+) and their cooperativity factors (alpha) affecting the dissociation constants (K(D), K(i)) of [(3)H]WAY-100635, [(3)H]8-OH-DPAT, and serotonin (5-HT), the endogenous neurotransmitter. Zn(2+) (5microM-1mM) inhibited the binding of agonist/antagonist to 5-HT1A receptors, mostly by decreasing both the ligands' affinity and the maximal number of sites. In [(35)S]GTPgammaS binding assays Zn(2+) behaved as insourmountable antagonist of 5-HT1A receptors, in agreement with radioligand binding assays. The residues involved in the formation of the inhibitory binding site on the 5-HT1A receptor were assessed by using N-ethyl-maleimide (NEM) or diethylpyrocarbonate (DEPC) which modify preferentially cysteine and histidine residues, respectively. Exposure to both agents did not block the negative allosteric effects of Zn(2+) on agonist and antagonist binding. Our findings represent the first quantitative analysis of allosteric binding interactions for 5-HT(1A) receptors. The physiological significance of Zn(2+) modulation of 5-HT(1A) receptors is unclear, but the colocalization of 5-HT(1A) receptors and Zn(2+) in the nervous system (e.g. in the hippocampus and cerebral cortex) suggests that Zn(2+) released at nerve terminals may modulate signals generated by the 5-HT(1A) receptors in vivo. Finally, these findings suggest that synaptic Zn(2+) may be a factor influencing the effectiveness of therapies that rely on 5-HT(1A) receptor activity. | 18,951,909 |
Hemispheric asymmetries in discourse processing: evidence from false memories for lists and texts. | Previous research suggests that the right hemisphere (RH) may contribute uniquely to discourse and text processing by activating and maintaining a wide range of meanings, including more distantly related meanings. The present study used the word-lists false memory paradigm [Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 803-814.] to examine the hypothesis that difference between the two cerebral hemispheres in discourse processing may be due, at least partly, to memory representations for implicit text-related semantic information. Specifically, we tested the susceptibility of the left hemisphere (LH) and RH to unpresented target words following the presentation of semantically related words appearing in either word lists or short texts. Findings showed that the RH produced more false alarms than the LH for unpresented target words following either word lists or texts. These findings reveal hemispheric differences in memory for semantically related information and suggest that RH advantage in long-term maintenance of a wide range of text-related word meanings may be one aspect of its unique contribution to the construction of a discourse model. The results support the RH coarse semantic coding theory [Beeman, M. (1998). Coarse semantic coding and discourse comprehension. In M. Beeman & C. Chiarello (Eds.), Right hemisphere language comprehension: Perspectives from cognitive neuroscience (pp. 255-284). Mahwah, NJ: Erlbaum.] and suggest that hemispheric differences in semantic processing during language comprehension extend also to verbal memory. | 18,951,910 |
Inactivated rotavirus vaccines: a priority for accelerated vaccine development. | Live oral rotavirus vaccines have proven to be generally safe and effective to prevent severe dehydrating diarrhea among children in high and some middle income countries. However, concerns linger about rare but severe adverse events, such as intussusception and their efficacy against the full range of rotavirus serotypes. More importantly, live oral vaccines have been less immunogenic and results of trials to assess their efficacy in poor children of both Africa and Asia will not be available for 2-3 years. This review describes the rationale for developing an inactivated rotavirus vaccine (IRV) as an alternative approach should live oral vaccines not work well in these challenging populations. Studies have demonstrated the protective role of serum antibody in animals and children and the robust serum antibody response and protection against rotavirus infection in animal models following parenteral immunization with IRV. Four years after licensing the first new generation of rotavirus vaccine, we still remain several years away from knowing how well they work in the target populations. Research to develop alternative approaches should be fostered as an insurance policy to protect against suboptimal efficacy or unanticipated adverse events that could hinder global immunization and protection of all children. | 18,951,937 |
DNA based vaccination with a cocktail of plasmids encoding immunodominant Leishmania (Leishmania) major antigens confers full protection in BALB/c mice. | Despite the lack of effective vaccines against parasitic diseases, the prospects of developing a vaccine against leishmaniasis are still high. With this objective, we have tested four DNA based candidate vaccines encoding to immunodominant leishmania antigens (LACKp24, TSA, LmSTI1 and CPa). These candidates have been previously reported as capable of eliciting at least partial protections in the BALB/c mice model of experimental cutaneous leishmaniasis. When tested under similar experimental conditions, all of them were able to induce similar partial protective effects, but none could induce a full protection. In order to improve the level of protection we have explored the approach of DNA based vaccination with different cocktails of plasmids encoding to the different immunodominant Leishmania antigens. A substantial increase of protection was achieved when the cocktail is composed of all of the four antigens; however, no full protection was achieved when mice were challenged with a high dose of parasite in their hind footpad. The full protection was only achieved after a challenge with a low parasitic dose in the dermis of the ear. It was difficult to determine clear protection correlates, other than the mixture of immunogens induced specific Th1 immune responses against each component. Therefore, such an association of antigens increased the number of targeted epitopes by the immune system with the prospects that the responses are at least additive if not synergistic. Even though, any extrapolation of this approach when applied to other animal or human models is rather hazardous, it undoubtedly increases the hopes of developing an effective leishmania vaccine. | 18,951,941 |
Hippocampal neuronal subpopulations are differentially affected in double transgenic mice overexpressing frontotemporal dementia and parkinsonism linked to chromosome 17 tau and glycogen synthase kinase-3beta. | Glycogen synthase kinase-3beta (GSK-3beta) has been proposed as the main kinase able to phosphorylate tau aberrantly in Alzheimer's disease and in related tauopathies. We have previously generated a double transgenic mouse line overexpressing the enzyme GSK-3beta and tau protein carrying a triple frontotemporal dementia and parkinsonism linked to chromosome 17 mutation whose expression patterns overlap in CA1 (pyramidal neurons) and dentate gyrus (granular neurons). Here, we have used this transgenic model to analyze how axonal and somatodendritic neuronal compartments are affected in the hippocampus. Our data demonstrate that neuronal subpopulations respond differentially to increased GSK-3 activity. Thus, dentate gyrus granular neurons undergo apoptotic death with subsequent degeneration of the mossy fibers, while CA1 pyramidal neurons accumulate hyperphosphorylated tau both in the axonal and in the somatodendritic compartments. These studies also allow us to propose a model of spreading of pathology through the hippocampus as a consequence of GSK-3 and tau dysregulation. | 18,951,953 |
Characterization of Bacillus stearothermophilus infA and of its product IF1. | Bacillus stearothermophilus infA encoding translation initiation factor IF1 was cloned and expressed in Escherichia coli and its transcript and protein product characterized. Although the functional properties of B. stearothermophilus and E. coli IF1, compared in several translational tests in the presence of both homologous and heterologous components, are not entirely identical, the two proteins are interchangeable in an in vitro translational system programmed with a natural mRNA. The availability of purified B. stearothermophilus IF1 now allows us to analyze the translation initiation pathway using efficient in vitro tests based entirely on purified components derived from this thermophilic Gram-positive bacterium. | 18,951,960 |
Comparison of chlordecone and estradiol effects on splenic T-cells in (NZBxNZW)F(1) mice. | Previous studies have shown that treatment of ovariectomized females with 17-beta estradiol (E2) accelerates the development of autoimmunity in the (NZBxNZW)F(1) murine lupus model. Treatment with estrogenic organochlorine pesticides (OCPs) such as chlordecone produces a similar effect. Although it is reasonable to postulate that the effects of chlordecone and related OCPs on autoimmunity are due to their estrogenic effects, this has not been clearly demonstrated. The objective of this study was to compare effects of chlordecone and E2 on splenic T lymphocyte parameters plausibly related to autoimmunity; specifically, on T-cell phenotype and functions. Ovariectomized (NZBxNZW)F(1) mice were treated for 6 weeks with implanted sustained-release pellets containing chlordecone or E2 at dosing rates shown previously to significantly shorten time to onset of disease. E2, but not chlordecone, increased the percentage of activated and memory CD4 T-cells, and reduced naive CD4 T-cells. E2 also elevated CD25 and glucocorticoid-induced TNF receptor (GITR) levels in CD4 T-cells, an effect not shared by chlordecone. On the other hand, both chlordecone and E2 increased Bcl-2 expression in CD4 T-cells and reduced CD4 T-cell apoptosis without affecting their proliferation. Although both treatments increased TNF-alpha and IL-2 secretion by CD4 T-cells, only chlordecone increased secretion of IFN-gamma and GM-CSF. E2, but not chlordecone, increased IL-10 secretion. These observations indicate that although it is considered an estrogenic OCP, chlordecone exerts effects on splenic T-cells that are different in a number of ways from E2. | 18,951,962 |
Evaluation of a taste sensor instrument (electronic tongue) for use in formulation development. | A taste sensor instrument (electronic tongue) was evaluated to determine its utility in developing a taste-enhanced liquid formulation. To train the electronic tongue, human sensory panel data were collected for two prototype formulations, a solution of the drug in water and several marketed products. Studies using the electronic tongue were conducted to determine taste-masking effectiveness of formulations compared to a matching placebo, to establish correlation with human sensory data, and to evaluate unknown formulations and predict their bitterness scores. In the first experiment, the effectiveness of a proposed taste-masking strategy was determined by comparing formulation prototypes containing a bitter active pharmaceutical ingredient (API) against corresponding placebos (i.e. formulations without an active ingredient) using electronic tongue data. The analysis of the electronic tongue data was based on the assumption that the drug was well taste masked if the placebo matched the formulation with API. In a second set of experiments, electronic tongue data were compared to existing data from a human taste panel for several marketed products and prototype formulations. A good correlation (r(2)=0.99) was achieved from this comparison, and the relative taste of prototype formulations not tasted by humans was predicted. | 18,951,963 |
An alternative pathway for Alu retrotransposition suggests a role in DNA double-strand break repair. | The Alu family is a highly successful group of non-LTR retrotransposons ubiquitously found in primate genomes. Similar to the L1 retrotransposon family, Alu elements integrate primarily through an endonuclease-dependent mechanism termed target site-primed reverse transcription (TPRT). Recent studies have suggested that, in addition to TPRT, L1 elements occasionally utilize an alternative endonuclease-independent pathway for genomic integration. To determine whether an analogous mechanism exists for Alu elements, we have analyzed three publicly available primate genomes (human, chimpanzee and rhesus macaque) for endonuclease-independent recently integrated or lineage specific Alu insertions. We recovered twenty-three examples of such insertions and show that these insertions are recognizably different from classical TPRT-mediated Alu element integration. We suggest a role for this process in DNA double-strand break repair and present evidence to suggest its association with intra-chromosomal translocations, in-vitro RNA recombination (IVRR), and synthesis-dependent strand annealing (SDSA). | 18,951,971 |
Microsclerotia development in Verticillium dahliae: Regulation and differential expression of the hydrophobin gene VDH1. | The vascular wilt fungus Verticillium dahliae produces persistent resting structures, known as microsclerotia, which are important for this plant pathogen's long-term survival. Previously, we identified a hydrophobin gene (VDH1) that is necessary for microsclerotial production. The current study of VDH1's expression, and its regulation, was undertaken to provide insight into the largely uncharacterized molecular mechanisms relevant to microsclerotial development. Reporter gene analysis showed that VDH1 is specifically expressed in developing microsclerotia, as well as in hyphal fusions and conidiophores, suggesting that VDH1 mediates the development of microsclerotia from conidiophores and other hyphal structures. We report also on the effects of nutrient availability on the regulation of microsclerotial development in V. dahliae; the gene's activity appears to be regulated in response to carbon availability. Lastly, constitutive expression of VDH1 results in delayed disease symptom development, but has no noticeable effect on in vitro microsclerotial development. | 18,951,989 |
Human mitochondrial variants influence on oxygen consumption. | This work investigates if human mitochondrial variants influence on maximal oxygen consumption (VO(2max)). With this purpose we recruited, as a uniform population in term of nutritional habits and life style, 114 healthy male Spanish subjects that practiced fitness exercises 3-4 times a week. Once mtDNA haplogroups were determined, we found that J presents with lower VO(2max) (P=0.02) than nonJ variants. J has been related with a lower efficiency of electron transport chain (ETC), diminished ATP and ROS production. Thus, the difficult to compensate the mitochondrial energetic deficiency could explain the accumulation of J haplogroup in LHON and multiple sclerosis. Furthermore, the lower ROS production associated to J could also account for the accrual of this variant in elderly people consequent to a decreased oxidative damage. | 18,952,007 |
Cesarean delivery on maternal request: the impact on mother and newborn. | Mothers should be counseled that the most concerning risks related to maternal request cesarean delivery are neonatal respiratory morbidity and those that may affect the mother's future reproductive health, including life-threatening conditions, such as placenta accreta. The literature suggests that overall risks of maternal complications with cesarean delivery on maternal request are slightly lower than a trial of vaginal delivery and are primarily driven by the avoidance of unplanned or emergent cesarean deliveries and their associated increased rate of complications. When addressing risks and benefits with patients, there are three areas of importance. First, the risks for neonatal respiratory morbidity and abnormal placentation with future pregnancies should be emphasized. Secondly, there are many areas on which studies are lacking. Finally, numerous factors can alter the risks and benefits--such as culture, maternal obesity, and provider background--and should be acknowledged. | 18,952,018 |
Kinetic characterization and identification of a novel inhibitor of hypoxia-inducible factor prolyl hydroxylase 2 using a time-resolved fluorescence resonance energy transfer-based assay technology. | The human hypoxia-inducible factor prolyl hydroxylases 1, 2, and 3 (HIF-PHD1, -2, and -3) are thought to act as proximal sensors of cellular hypoxia by virtue of their mechanism-based dependence on molecular oxygen. These 2-oxoglutarate (2-OG) and non-heme iron-dependent oxygenases constitutively hydroxylate HIF, resulting in high-affinity binding to Von Hippel-Lindau protein (pVHL). Some reported affinities for the HIF-PHDs for 2-OG and iron approach the estimated physiological concentrations for these cofactors, suggesting that the system as described is not catalytically optimal. Here we report the enzymatic characterization of full-length recombinant human HIF-PHD2 using a novel and sensitive catalytic assay. We demonstrated submicromolar affinities for 2-OG and ferrous iron and HIF-PHD2 Km values for oxygen that are greater than atmospheric oxygen levels, suggesting that molecular oxygen is indeed the key regulator of this pathway. In addition, we observed enhancement of HIF-PHD2 catalytic activity in the presence of ascorbic acid with only minor modifications of HIF-PHD2 requirements for 2-OG, and a detailed pH study demonstrated optimal HIF-PHD2 catalytic activity at pH 6.0. Lastly, we used this sensitive and facile assay to rapidly perform a large high-throughput screen of a chemical library to successfully identify and characterize novel 2-OG competitive inhibitors of HIF-PHD2. | 18,952,043 |
Intrinsic uncoupling in the ATP synthase of Escherichia coli. | The ATP hydrolysis activity and proton pumping of the ATP synthase of Escherichia coli in isolated native membranes have been measured and compared as a function of ADP and Pi concentration. The ATP hydrolysis activity was inhibited by Pi with an half-maximal effect at 140 microM, which increased progressively up in the millimolar range when the ADP concentration was progressively decreased by increasing amounts of an ADP trap. In addition, the relative extent of this inhibition decreased with decreasing ADP. The half-maximal inhibition by ADP was found in the submicromolar range, and the extent of inhibition was enhanced by the presence of Pi. The parallel measurement of ATP hydrolysis activity and proton pumping indicated that, while the rate of ATP hydrolysis was decreased as a function of either ligand, the rate of proton pumping increased. The latter showed a biphasic response to the concentration of Pi, in which an inhibition followed the initial stimulation. Similarly as previously found for the ATP synthase from Rhodobacter caspulatus [P. Turina, D. Giovannini, F. Gubellini, B.A. Melandri, Physiological ligands ADP and Pi modulate the degree of intrinsic coupling in the ATP synthase of the photosynthetic bacterium Rhodobacter capsulatus, Biochemistry 43 (2004) 11126-11134], these data indicate that the E. coli ATP synthase can operate at different degrees of energetic coupling between hydrolysis and proton transport, which are modulated by ADP and Pi. | 18,952,048 |
Suppressive effects of retinoids on iron-induced oxidative stress in the liver. | We previously reported that impaired retinoid signaling in the liver causes steatohepatitis and hepatocellular carcinoma. Recently, oxidative stress induced by hepatic iron overload has emerged as an important factor for the progression of liver disease in patients with chronic hepatitis C, alcoholic liver disease, and nonalcoholic steatohepatitis. In this study, the relationship between retinoid signaling and iron metabolism in the liver was investigated. The effect of retinoids on the iron metabolism was examined in HuH7 cells treated with all-trans retinoic acid and acyclic retinoid NIK-333. In in vivo experiments, we used the mice expressing the dominant negative form of retinoic acid receptor alpha gene under the control of albumin enhancer/promoter (RAR-E Tg) and iron-overloaded wild mice fed with retinoid-deficient and retinoid-excess diets. Hepatic iron accumulation and increased expression of hemojuvelin were observed in RAR-E Tg mouse liver. Retinoid treatment significantly suppressed expression of hemojuvelin and mildly suppressed expression of transferrin receptor type 2 and hepcidin, accompanied by decreased hepatic iron content and iron-induced oxidative stress in vitro and in vivo. Overexpression of hemojuvelin in HuH7 hepatoma cells led to a significant increase in cellular iron content. Our results suggest that retinoids are involved in hepatic iron metabolism through transcriptional regulation of hemojuvelin. This study demonstrated a novel functional role of retinoids in preventing iron-induced oxidative stress in the liver. | 18,952,085 |
Morphology and kinetics of the three distinct phases of red blood cell invasion by Plasmodium falciparum merozoites. | The invasion of red blood cells (RBCs) is an essential event in the life cycle of all malaria-causing Plasmodium parasites; however, there are major gaps in our knowledge of this process. Here, we use video microscopy to address the kinetics of RBC invasion in the human malaria parasite Plasmodium falciparum. Under in vitro conditions merozoites generally recognise new target RBCs within 1 min of their release from their host RBC. Parasite entry ensues and is complete on average 27.6s after primary contact. This period can be divided into two distinct phases. The first is an approximately 11s 'pre-invasion' phase that involves an often dramatic RBC deformation and recovery process. The second is the classical 'invasion' phase where the merozoite becomes internalised within the RBC in a approximately 17s period. After invasion, a third 'echinocytosis' phase commences when about 36 s after every successful invasion a dramatic dehydration-type morphology was adopted by the infected RBC. During this phase, the echinocytotic effect reached a peak over the next 23.4s, after which the infected RBC recovered over a 5-11 min period. By then the merozoite had assumed an amoeboid-like state and was apparently free in the cytoplasm. A comparison of our data with that of an earlier study of the distantly related primate parasite Plasmodium knowlesi indicated remarkable similarities, suggesting that the kinetics of invasion are conserved across the Plasmodium genus. This study provides a morphological and kinetic framework onto which the invasion-associated physiological and molecular events can be overlaid. | 18,952,091 |
Crystal structure of the erythromycin polyketide synthase dehydratase. | The dehydratases (DHs) of modular polyketide synthases (PKSs) catalyze dehydrations that occur frequently in the biosynthesis of complex polyketides, yet little is known about them structurally or mechanistically. Here, the structure of a DH domain, isolated from the fourth module of the erythromycin PKS, is presented at 1.85 A resolution. As with the DH of the highly related animalian fatty acid synthase, the DH monomer possesses a double-hotdog fold. Two symmetry mates within the crystal lattice make a contact that likely represents the DH dimerization interface within an intact PKS. Conserved hydrophobic residues on the DH surface indicate potential interfaces with two other PKS domains, the ketoreductase and the acyl carrier protein. Mutation of an invariant arginine at the hypothesized acyl carrier protein docking site in the context of the erythromycin PKS resulted in decreased production of the erythromycin precursor 6-deoxyerythronolide B. The structure elucidates how the alpha-hydrogen and beta-hydroxyl group of a polyketide substrate interact with the catalytic histidine and aspartic acid in the DH active site prior to dehydration. | 18,952,099 |
Tracking prey or tracking the prey's resource? Mechanisms of movement and optimal habitat selection by predators. | We synthesize previous theory on ideal free habitat selection to develop a model of predator movement mechanisms, when both predators and prey are mobile. We consider a continuous environment with an arbitrary distribution of resources, randomly diffusing prey that consume the resources, and predators that consume the prey. Our model introduces a very general class of movement rules in which the overall direction of a predator's movement is determined by a variable combination of (i) random diffusion, (ii) movement in the direction of higher prey density, and/or (iii) movement in the direction of higher density of the prey's resource. With this model, we apply an adaptive dynamics approach to two main questions. First, can it be adaptive for predators to base their movement solely on the density of the prey's resource (which the predators do not consume)? Second, should predator movements be exclusively biased toward higher densities of prey/resources, or is there an optimal balance between random and biased movements? We find that, for some resource distributions, predators that track the gradient of the prey's resource have an advantage compared to predators that track the gradient of prey directly. Additionally, we show that matching (consumers distributed in proportion to resources), overmatching (consumers strongly aggregated in areas of high resource density), and undermatching (consumers distributed more uniformly than resources) distributions can all be explained by the same general habitat selection mechanism. Our results provide important groundwork for future investigations of predator-prey dynamics. | 18,952,108 |
Expression profiles of cytokines released in intestinal epithelial cells of the rainbow trout, Oncorhynchus mykiss, in response to bacterial infection. | To determine whether fish intestinal epithelial cells (IECs) contribute to mucosal immunity, we established a method for isolating IECs from the rainbow trout Oncorhynchus mykiss and examined cytokine production in these cells. Components of the intestinal epithelium were released by incubation of intestinal pieces with 1mM dithiothreitol (DTT)/ethylenediamine tetraacetic acid (EDTA). The IEC-rich fraction (purity >90%; survival rate approximately 95%) was obtained by centrifugation on a 35%/40% Percoll gradient, followed by magnetic cell sorting using an anti-trout IgM antiserum. The gene expression profiles of 14 cytokines in trout IECs were investigated after culturing the cells for 6h with or without the pathogenic bacterium Aeromonas salmonicida. Trout IECs could produce several cytokines, of which IL-1beta and TNFalpha2 were upregulated when the cells were stimulated with live A. salmonicida. Immunohistochemical analyses with the anti-trout TNF antibody confirmed that the TNF protein was present in the IECs of trout that were intra-anally challenged with live A. salmonicida. These results show that trout IECs are an important trigger of the intestinal immune system. Further, formalin-killed A. salmonicida, conditioned medium of this bacterium, or live nonpathogenic Escherichia coli could not upregulate the expression of these cytokines. These results indicate that the production of inflammatory cytokines by IECs is caused by the adhesion of A. salmonicida, but is not due to only simple ligand-receptor interactions between the surface molecules of IECs and the bacterium or in response to bacterial secretions. | 18,952,122 |
The zinc finger protein A20 targets TRAF2 to the lysosomes for degradation. | The zinc finger-containing protein A20 is a negative regulator of TNF-induced JNK (c-Jun-N-terminal kinase) and NFkappaB (nuclear factor kappaB) signaling. A20 is an unusual enzyme that contains both ubiquitinating and deubiquitinating activities. Although A20 is mostly localized in the cytosol, our recent studies reveal that a fraction of A20 can associate with a lysosome-interacting compartment in a manner that requires its carboxy terminal zinc fingers, but independent of its ubiquitin modifying activities. Whether the lysosome-associated A20 has a function in cellular signaling is unclear. Here, we demonstrate that A20 is capable of targeting an associated signaling molecule such as TRAF2 to the lysosomes for degradation. This process is dependent on the membrane tethering zinc finger domains of A20, but does not require A20 ubiquitin modifying activity. Our findings suggest a novel mode of A20 action that involves lysosomal targeting of signal molecules bound to A20. | 18,952,128 |
MBL2 single nucleotide polymorphism diversity among four ethnic groups as revealed by a bead-based liquid array profiling. | In the present work we established a rapid, cost-effective and high-throughput method for genotyping using a multiplexed microsphere-based suspension array platform - Luminex xMAP which enabled us to analyze 3 SNPs in the MBL2 gene promoter and 5' UTR, and 3 coding SNPs exon 1 haplotypes, associated with different levels of MBL2 expression. Using this system MBL2 diversity in four different ethnic groups, namely, Asian (Japanese), Caucasian, Hispanic and African-American-assessed. Results showed significant variability in terms of allele, genotype, and haplotype distribution. Characteristic MBL haplotype patterns were defined for each ethnic group. A prevalence of haplotypes coding functional proteins capable of complement activation and pathogen opsonization was observed. Regardless of the significant diversity of individual haplotypes, a high, almost similar (25-28%) proportion of haplotypes associated with MBL deficiency was found in the four ethic groups. The proportion of individuals homozygous for the haplotypes resulting in complete MBL2 deficiency was also significant (2-10%). Considering the role of MBL2 in innate immunity and as a clinically relevant marker, the genotyping approach developed and the knowledge of the genetic variation in different ethnic groups will be relevant to future medical genetic studies. | 18,952,132 |
Identification of an unusual AT(D)Pase-like activity in multifunctional NAD glycohydrolase from the venom of Agkistrodon acutus. | NAD-glycohydrolases (NADases) are ubiquitous enzymes that possess NAD glycohydrolase, ADPR cyclase or cADPR hydrolase activity. All these activities are attributed to the NADase-catalyzed cleavage of C-N glycosyl bond. AA-NADase purified from the venom of Agkistrodon acutus is different from the known NADases, for it consists of two chains linked with disulfide-bond(s) and contains one Cu(2+) ion. Here, we show that AA-NADase is not only able to cleave the C-N glycosyl bond of NAD to produce ADPR and nicotinamide, but also able to cleave the phosphoanhydride linkages of ATP, ADP and AMP-PNP to yield AMP. AA-NADase selectively cleaves the P-O-P bond of ATP, ADP and AMP-PNP without the cleavage of P-O-P bond of NAD. The hydrolysis reactions of NAD, ATP and ADP catalyzed by AA-NADase are mutually competitive. ATP is the excellent substrate for AA-NADase with the highest specificity constant k(cat)/K(m) of 293+/-7mM(-1)s(-1). AA-NADase catalyzes the hydrolysis of ATP to produce AMP with an intermediate ADP. AA-NADase binds with one AMP with high affinity determined by isothermal titration calorimetry (ITC). AMP is an efficient inhibitor against NAD. AA-NADase has so far been identified as the first unique multicatalytic enzyme with both NADase and AT(D)Pase-like activities. | 18,952,139 |
Mechanisms of human inherited epilepsies. | It is just over a decade since the discovery of the first human epilepsy associated ion channel gene mutation. Since then mutations in at least 25 different genes have been described, although the strength of the evidence for these genes having a pathogenic role in epilepsy varies. These discoveries are allowing us to gradually begin to unravel the molecular basis of this complex disease. In the epilepsies, virtually all the established genes code for ion channel subunits. This has led to the concept that the idiopathic epilepsies are a family of channelopathies. This review first introduces the epilepsy syndromes linked to mutations in the various genes. Next it collates the genetic and functional analysis of these genes. This part of the review is divided into voltage-gated channels (Na+, K+, Ca2+, Cl(-) and HCN), ligand-gated channels (nicotinic acetylcholine and GABA(A) receptors) and miscellaneous proteins. In some cases significant advances have been made in our understanding of the molecular and cellular deficits caused by mutations. However, the link between molecular deficit and clinical phenotype is still unknown. Piecing together this puzzle should allow us to understand the underlying pathology of epilepsy ultimately providing novel therapeutic strategies to complete the clinic-bench-clinic cycle. | 18,952,142 |
Genetic study of an American family with DYT3 dystonia (lubag). | X-linked dystonia-parkinsonism (XDP, DYT3), endemic in the Philippine island of Panay, is characterized by the clinical onset with dystonia followed by parkinsonism. We found a 35-year-old American male patient, originally from Panay with typical XDP, has a 2-year history of parkinsonism, dystonia, and tremor. Ancestral DYT3 haplotype and disease-specific SVA (short interspersed nuclear element, variable number of tandem repeats, and Alu composite) retrotransposon insertion were identified in the DYT3 proband and two female unaffected family members. No mutation(s) and expression changes in peripheral blood lymphocytes were observed in the TATA-binding protein-associated factor 1 gene (TAF1) or the chemokine CXC motif receptor 3 gene (CXCR3) of the proband or other DYT3 carriers. These findings indicate blood DNA test has a diagnostic utility and implications for genetic counseling in families with DYT3. In contrast, TAF1 and CXCR3 gene expression in peripheral blood lymphocytes is not a suitable surrogate disease marker for DYT3. | 18,952,144 |
I.c.v. administration of orexin-A induces an antidepressive-like effect through hippocampal cell proliferation. | A decrease in orexin-A (OX-A) levels has been reported to be associated with depression. It is also well known that stress and depression can disrupt neurogenesis in the dentate gyrus of the hippocampus; however, it is unclear how OX-A is involved in depression and/or neurogenesis. In the present study, we investigated the effect of i.c.v. administration of OX-A on the forced swimming test (FST), an accepted behavioral screen of antidepressant-like activity, and on the cell proliferation with bromodeoxyuridine (BrdU) in the dentate gyrus at 4 days after i.c.v. administration of OX-A. OX-A administration (140 pmol/mouse) led to a significant reduction in animal immobility in the FST, without affecting spontaneous locomotor activities or serum corticosterone levels. In addition, the number of BrdU-positive cells in the dentate gyrus was significantly increased in OX-A-treated mice in vivo; however, OX-A did not affect the percentage of doublecortin-positive cells in the dentate gyrus. The proliferation of neural progenitor cells derived from rat fetal brain was not affected by OX-A treatment in vitro, and the orexin receptor 1 (OXR1) protein was not expressed in these cells. Treatment with the OXR1 antagonist SB-334867 (30 mg/kg, i.p.) blocked both the OX-A-induced decrease in the immobility of FST and increase in BrdU-positive. Moreover, the OX-A-induced increase in neuropeptide Y (NPY)-positive cells in the hilus of the dentate gyrus was blocked by SB-334867. These results suggest that OX-A induces an antidepressive-like effect, at least in part, via the enhancement of cell proliferation in the dentate gyrus. These effects of OX-A also may be partly relevant to the regulation of the NPY system in the hilus of the dentate gyrus. | 18,952,152 |
Functionally modified gelatin microspheres impregnated collagen scaffold as novel wound dressing to attenuate the proteases and bacterial growth. | An attempt was made to develop a new therapeutic delivery system which would play a dual role of attenuating MMP activity in the wounds and also prevent infection by controlled delivery of antimicrobials. A catechol type MMP inhibitor 2,3-dihydroxybenzoic acid (DHBA) was conjugated to gelatin microspheres using EDC/NHS as coupling agents. The potential of the modified gelatin microspheres (DHB-MS) to attenuate the proteases such as MMP 2 and MMP 9 in the diabetic wound tissues was investigated by gelatin zymography. Further the modified microspheres were loaded with doxycycline and impregnated in a reconstituted collagen scaffold as novel wound dressing. The in vitro release behavior of doxycycline from both DHB-MS and DHB-MS impregnated collagen scaffold was investigated. DHB-MS when incubated with the tissue lysate for 6h displayed the complete inhibition of the MMPs in the tissue lysate. The in vitro drug release studies from the collagen scaffold exhibited the burst release of 44%, exerted immediate chemo prophylaxis and sustained delivery for 72 h. The MTT assay and fluorescent labeling with calcein AM indicated that the DHB-MS is biocompatible to human foreskin fibroblasts. Thus the system developed provides wider scope to control the pathogens involved in infection and also the excess matrix degradation. | 18,952,165 |
High-cell density shake-flask expression and rapid purification of the large fragment of Thermus aquaticus DNA polymerase I using a new chemically and temperature inducible expression plasmid in Escherichia coli. | We have developed a new expression vector, pcI(ts) ind(+), based upon the powerful rightward promoter of bacteriophage lambda, which is controlled by a temperature-sensitive and chemically-inducible version of the lambda repressor on the same plasmid. Locating the repressor gene on the plasmid makes this vector "portable" in that it can be used to transform any strain of Escherichia coli. Hence, control over strains, induction conditions, and harvest times can be used to optimize yields of heterologous proteins. To provide a proof of concept, we show that E. coli recA(+) and recA(-) host cells transformed with pcI(ts) ind(+) modKlenTaq1 (a modified version of the large fragment of Thermus aquaticus DNA polymerase I) could be grown to high cell densities in multiple shake-flasks. A mutant version of modKlenTaq1 (V649C) could be induced by simply raising the thermostat setting from 30 to 37 degrees C and (in the case of recA(+) cells) adding nalidixic acid to achieve full induction (12-13% of the total cellular protein). Using a rapid, two-step purification process, it was possible to purify nearly 300 mg of modKlenTaq1 V649C from six 2.8-L baffle-bottomed shake-flasks each holding 1.5L of culture for a final yield of approximately 33 mg per liter or 3mg of purified enzyme per gram of cells wet weight. | 18,952,180 |
Three galactose inducible promoters for use in C. neoformans var. grubii. | Cryptococcus neoformans is the causative agent of cryptococcal meningoencephalitis, most frequently occurring in immunocompromised individuals. There are three varieties of C. neoformans, var. grubii, var. neoformans, and var. gatti. Worldwide var. grubii is the most prevalent clinical isolate. However, few tools for the study of essential genes in var. grubii exist. Here we describe three endogenous inducible promoters for use in the study of this important opportunistic pathogen. We identified eight potential homologs of S. cerevisiae galactose genes in var. grubii. We found that GAL1, GAL7, and UGE2 were regulated by glucose and galactose and can be used successfully during mating. Our analysis indicated these promoters should prove to be excellent tools for analysis of genes in var. grubii. | 18,952,189 |
Development of a matrix solid-phase dispersion method for the simultaneous determination of pyrethroid and organochlorinated pesticides in cattle feed. | A matrix solid-phase dispersion (MSPD) method was developed for the simultaneous extraction of 36 common pesticides and breakdown products (mostly pyrethroids and organochlorines) in cattle feed. Different parameters affecting the extraction efficiency (such as dispersing phase, clean-up adsorbent and elution volume) were investigated. The experimental procedure was optimized using a multivariate statistical approach and the final analyses were carried out by GC-muECD. Several protocols for extract purification were also studied. As far as we know, this is the first application of MSPD for the extraction of most of the target pesticides from animal feed. Using the optimized extraction conditions, the method was validated in terms of accuracy, and precision (within-a-day and among-days), using a certified reference material (CRM 115) as well as spiked cattle feedingstuffs at different concentration levels. A matrix effect study was also carried out using various real samples. The recoveries were satisfactory (>75% in most cases) and the quantification limits, at the sub-ngg(-1) or low-ngg(-1) level, complied with the regulated maximum residue levels (MRLs) in animal feed and in main crops used in the preparation of cattle feeding materials. Finally, the MSPD-GC-muECD methodology was applied to the analysis of real cattle feed samples collected in farms of dairy cattle from NW Spain. | 18,952,214 |
Quantification of N-acetyl- and N-glycolylneuraminic acids by a stable isotope dilution assay using high-performance liquid chromatography-tandem mass spectrometry. | The present report describes a method for the quantification of N-acetyl- and N-glycolylneuraminic acids without any derivatization, using their (13)C(3)-isotopologues as internal standards and a C(18) reversed-phase column modified by decylboronic acid which allows for the first time a complete chromatographic separation between the two analytes. The method is based on high-performance liquid chromatographic coupled with electrospray ion-trap mass spectrometry. The limit of quantification of the method is 0.1mg/L (2.0ng on column) for both analytes. The calibration curves are linear for both sialic acids over the range of 0.1-80mg/L (2.0-1600ng on column) with a correlation coefficient greater than 0.997. The proposed method was applied to the quantitative determination of sialic acids released from fetuin as a model of glycoproteins. | 18,952,219 |
Upregulation of protein kinase cdelta in vascular smooth muscle cells promotes inflammation in abdominal aortic aneurysm. | The development of abdominal aortic aneurysms (AAAs) involves a complex interplay of extracellular matrix degradation, inflammation, and apoptosis. We have previously shown that protein kinase Cdelta (PKCdelta) plays a critical role in vascular smooth muscle cell (vSMC) apoptosis in the setting of oxidative stresses. Here, we show that PKCdelta is also involved in the signaling that draws inflammatory cells to aneurismal tissue. Immunostaining for monocyte chemotactic factor (MCP)-1 and PKCdelta was performed on paraffin-fixed arterial sections. Enzyme-linked immunosorbent assay to detect MCP-1 produced by vSMCs was performed on media from cultured rat A10 cells after cytokine induction with or without the PKCdelta-specific inhibitor rottlerin. Migration of isolated lymphocytes was evaluated in response to media from activated A10 cells. Human AAAs show widespread and elevated expression of PKCdelta that is not seen in normal aortic tissues. Cytokine stimulation of cultured vSMCs induced vigorous production of the key chemotactant MCP-1, the expression of which was PKCdelta dependent. Stimulated vSMCs were capable of inducing the migration of leukocytes, and this effect was also dependent on PKCdelta activity. Staining of human AAA tissue for MCP-1 showed an expression pattern that was identical to that of PKCdelta and smooth muscle specific alpha-actin. PKCdelta is widely expressed in human AAA vessel walls and mediates MCP-1 expression by vSMCs, which could contribute to the inflammatory process. These findings, coupled with earlier studies of PKCdelta, suggest that PKCdelta plays a central role in the pathogenesis of AAAs and may be a potential target for future therapies. | 18,952,226 |
Norepinephrine-mediated suppression of phagocytosis by wound neutrophils. | The systemic response to injury is characterized by massive release of norepinephrine (NE) into the circulation as a result of global sympathetic activation. Multiple authors have demonstrated NE-mediated alterations in migration of circulating neutrophils to wounds. We hypothesized that NE further alters wound neutrophil phagocytic function through adrenergic signaling pathways. A standard subcutaneous sponge wound model was used. Murine wound neutrophils were harvested at 24 and 120 h after injury and treated with physiological (10(-9) M) and pharmacologic (10(-6) M) doses of NE. Phagocytosis of green fluorescent protein-labeled Escherichia coli was assayed by flow cytometry. The signaling pathways mediating NE modulation of phagocytosis by wound neutrophils were defined by pharmacologic manipulation of alpha- and beta-adrenoreceptors and protein kinase A. Pharmacologic-dose NE, but not-physiological-dose NE, suppressed the phagocytic efficiency of 120-h wound neutrophils. This alteration in phagocytic efficiency appears to be mediated through alpha- and beta- adrenoreceptors and downstream protein kinase A. Phagocytosis by 24-h wound neutrophils was not impacted by NE treatment. The present study is the first to demonstrate NE-mediated alterations in the process of phagocytosis by wound neutrophils. We conclude that NE plays a temporally and dose-defined immunomodulatory role in cutaneous wound healing through alterations in phagocytosis by wound neutrophils and may represent a target for therapeutic manipulation of the innate immune response. | 18,952,237 |
Substance P enhances wound closure in nitric oxide synthase knockout mice. | The neuropeptide, substance P (SP), up-regulates nitric oxide production (NO). The purpose of this study was to determine whether SP enhances response to cutaneous injury in nitric oxide synthase knockout (NOS null) mice. We studied mice with targeted deletions of the 3 NOS genes, neuronal NOS, inducible NOS, or endothelial NOS. Full thickness dorsal wounds were treated daily (d 0-6) with topical SP or normal saline (NaCl). Wounds were analyzed by flow cytometry for macrophage, leukocyte, endothelial, and dendritic cells. Healing time and wound epithelialization were compared using analysis of variance. Wound closure in the 3 NOS null mice was slower than the control mice (P < 0.05). SP treatment enhanced wound closure in NOS null mice (P < 0.02). NOS null wounds exhibited reduced inflammation. SP increased macrophage, leukocyte, and dendritic cell densities at d 3 and d 7 (P < 0.05) in all NOS null mice. SP increased endothelial cell number in neuronal NOS and inducible NOS null mice, but not in endothelial NOS null mice (P > 0.05). SP ameliorated the impaired wound healing response observed in NOS null mice by enhancing wound closure kinetics and epithelialization. SP increased inflammatory cell density in the wounds supporting the essential role of inflammatory cells, especially macrophages, in wound repair. | 18,952,239 |
Detection of spatial fluctuations of non-point source fecal pollution in coral reef surrounding waters in southwestern Puerto Rico using PCR-based assays. | Human fecal contamination of coral reefs is a major cause of concern. Conventional methods used to monitor microbial water quality cannot be used to discriminate between different fecal pollution sources. Fecal coliforms, enterococci, and human-specific Bacteroides (HF183, HF134), general Bacteroides-Prevotella (GB32), and Clostridium coccoides group (CP) 16S rDNA PCR assays were used to test for the presence of non-point source fecal contamination across the southwestern Puerto Rico shelf. Inshore waters were highly turbid, consistently receiving fecal pollution from variable sources, and showing the highest frequency of positive molecular marker signals. Signals were also detected at offshore waters in compliance with existing microbiological quality regulations. Phylogenetic analysis showed that most isolates were of human fecal origin. The geographic extent of non-point source fecal pollution was large and impacted extensive coral reef systems. This could have deleterious long-term impacts on public health, local fisheries and in tourism potential if not adequately addressed. | 18,952,244 |
Speciation analysis of arsenic in terrestrial plants from arsenic contaminated area. | Arsenic speciation analysis was carried out in plants collected from arsenic contaminated area. Two plant species were chosen for the investigation: Reed Grass (Calamagrostis arundinacea) and Lady Fern (Athyrium filix-femina). To characterize arsenic species several different extraction procedures were applied including enzymatic extraction and extraction using surfactant solution (SDS). Two-step sequential extraction (water+SDS) that assures the highest extraction efficiency was applied to extract arsenic species from plant material. HPLC with anion-exchange column was used to separate extracted arsenic compounds and ICP-MS was applied for quantitative arsenic determination after species separation. | 18,952,257 |
A model for simultaneous crystallisation and biodegradation of biodegradable polymers. | This paper completes the model of biodegradation for biodegradable polymers that was previously developed by Wang et al. (Wang Y, Pan J, Han X, Sinka, Ding L. A phenomenological model for the degradation of biodegradable polymers. Biomaterials 2008;29:3393-401). Crystallisation during biodegradation was not considered in the previous work which is the topic of the current paper. For many commonly used biodegradable polymers, there is a strong interplay between crystallisation and hydrolysis reaction during biodegradation - the chain cleavage caused by the hydrolysis reaction provides an extra mobility for the polymer chains to crystallise and the resulting crystalline phase becomes more resistant to further hydrolysis reaction. This paper presents a complete theory to describe this interplay. The fundamental equations in the Avrami's theory for crystallisation are modified and coupled to the diffusion-reaction equations that were developed in our previous work. The mathematical equations are then applied to three biodegradable polymers for which long term degradation data are available in the literature. It is shown that the model can capture the behavior of the major biodegradable polymers very well. | 18,952,280 |
Assessment of biomarkers of cadmium stress in lettuce. | Laboratory and field studies have provided encouraging insights into the capacity of plants to act as biomonitors of environmental quality through the use of biomarkers. However, a better understanding of the overall process of Cd-induced senescence, describing the cascade of Cd effects in plants is needed for a selection of relevant biomarkers of Cd stress. In order to approach this, 5-week old Lactuca sativa L. were exposed for 14 days to 100muM Cd(NO(3))(2) and harvested at days 0, 1, 3, 7 and 14. The parameters measured included classical endpoints (shoot and root growth) and biochemical endpoints related to photosynthesis, nutrients content, and oxidative stress. Cadmium-exposed plants displayed nutrient imbalances in leaves and roots. Photosynthetic efficiency was significantly decreased and lipid peroxidation was enhanced. Antioxidant enzymes were significantly altered during exposure-catalase was inhibited by the end of exposure and peroxidase was induced at day 1 in young leaves. These alterations culminated in a decrease in shoot growth after 14-days exposure to Cd. Biochemical alterations could be used in integrative approaches with classical endpoints in ecotoxicological tests for Cd and after further testing in real scenarios conditions, they could form the basis of a plant biomarkers battery for monitoring and predicting early effects of exposure to Cd. | 18,952,284 |
OS9 interacts with DC-STAMP and modulates its intracellular localization in response to TLR ligation. | Dendritic cell-specific transmembrane protein (DC-STAMP) has been first identified as an EST in a cDNA library of human monocyte-derived dendritic cells (DC). DC-STAMP is a multimembrane spanning protein that has been implicated in skewing haematopoietic differentiation of bone marrow cells towards the myeloid lineage, and in cell fusion during osteoclastogenesis and giant cell formation. To gain molecular insight in how DC-STAMP exerts its function, DC-STAMP interacting proteins were identified in a yeast-2-hybrid analysis. Herein, we report that amplified in osteosarcoma 9 (OS9) physically interacts with DC-STAMP, and that both proteins colocalize in the endoplasmic reticulum in various cell lines, including immature DC. OS9 has previously been implicated in ER-to-Golgi transport and transcription factor turnover. Interestingly, we now demonstrate that toll-like receptor (TLR)-induced maturation of DC leads to the translocation of DC-STAMP from the ER to the Golgi while OS9 localization is unaffected. Applying TLR-expressing CHO cells we could confirm ER-to-Golgi translocation of DC-STAMP following TLR stimulation and demonstrated that the DC-STAMP/OS9 interaction is involved in this process. Collectively, the data indicate that OS9 is critically involved in the modulation of ER-to-Golgi transport of DC-STAMP in response to TLR triggering, suggesting a novel role for OS9 in myeloid differentiation and cell fusion. | 18,952,287 |
Nylon wool purification alters the activation of T cells. | Purification of lymphocytes, particularly T cells, is commonly performed using nylon wool. This enrichment method selectively retains B cells and some myeloid cells allowing a significantly more pure T cell population to flow through a nylon wool column. T cells purified in this fashion are assumed to be unaltered and functionally naïve, however some studies have suggested aberrant in vitro T cell responses after nylon wool treatment. We found that nylon wool purification significantly altered T cell proliferation, expression of activation markers and production of cytokines. Our results suggest that nylon wool treatment modifies T cell activation responses and that caution should be used when choosing this purification method. | 18,952,296 |
Morphological and immunological characteristics of the bovine temporal lymph node and hemal node. | Anatomical dissection of the temporal regions of 62 cattle demonstrated that lymph nodes and hemal nodes are present in 89% of the animals (bilaterally in 65% and unilaterally in 24% of the cases). Lymph nodes accounted for 60% and hemal nodes for 40% of all examined nodes. They are nearly always round with diameters ranging from 1 to 9mm. Injections of India ink showed that their drainage area consists of the forehead, the upper eyelid, the base of the horn and the temporal muscle. Immunohistochemistry and flow cytometry revealed that the distribution and percentages of the different cell populations in the lymph nodes and hemal nodes are similar to other cranial lymph nodes. Based on its anatomical location the name temporal lymph node (lymphonodus temporalis) is proposed. | 18,952,301 |
Boost first, eliminate systematic error, and individualize CTV to PTV margin when treating lymph nodes in high-risk prostate cancer. | The purpose of this report is to evaluate the movement of the planning target volume (PTV) in relation to the pelvic lymph nodes (PLNs) during treatment of high-risk prostate cancer. We reviewed the daily treatment course of ten consecutively treated patients with high-risk prostate cancer. PLNs were included in the initial PTV for each patient. Daily on-board imaging of gold fiducial markers implanted in the prostate was used; daily couch shifts were made as needed and recorded. We analyzed how the daily couch shifts impacted the dose delivered to the PLN. A PLN clinical target volume was identified in each man using CT-based treatment planning. At treatment planning, median minimum planned dose to the PLN was 95%, maximum 101%, and mean 97%. Daily couch shifting to prostate markers degraded the dose slightly; median minimum dose to the PLN was 92%, maximum, 101%, and mean delivered, 96%. We found two cases, where daily systematic shifts resulted in an underdosing of the PLN by 9% and 29%, respectively. In other cases, daily shifts were random and led to a mean 2.2% degradation of planned to delivered PLN dose. We demonstrated degradation of the delivered dose to PLN PTV, which may occur if daily alignment only to the prostate is considered. To improve PLN PTV, it maybe preferable to deliver the prostate/boost treatment first, and adapt the PTV of the pelvic/nodal treatment to uncertainties documented during prostate/boost treatment. | 18,952,307 |
High precision transponder localization using a novel electromagnetic positioning system in patients with localized prostate cancer. | The Micropos 4DRT system is being developed to provide accurate, precise, objective, and continuous target localization during radiotherapy. This study involves the first in vivo use of the system, aiming to evaluate the localization accuracy of this electromagnetic positioning technique compared with radiographic localization and to assess its real-time tracking ability. An active positioning marker was inserted in the prostatic urethra of 10 patients scheduled to receive radiotherapy for localized prostate cancer. A receiving sensor plate (antennae system) was placed at a known position in the treatment tabletop. Initial in vivo system calibrations were performed in three subjects. Ten additional patients were then enrolled in a study arm that compared radiographic transponder location to radiotransponder location simultaneously acquired by the Micropos 4DRT system. Frontal and side radiographs were taken with the radiopaque transponder located at three different positions within the prostatic urethra. The transponder insertions were all successful and without complications. Comparison of the transponder location as per the Micropos 4DRT system with the radiographic transponder localization showed an average (+/-SD) absolute and relative 3D difference of 2.7+/-1.2 and 1.7+/-1.0mm, respectively. Continuous transponder tracking capability was also demonstrated. Electromagnetic positioning using the Micropos transponder system is feasible in vivo. Evaluation of this novel non-ionizing localization system, in this study using a transponder positioned in the prostatic urethra, indicates transponder localization accuracy to isocenter comparable with X-ray localization of a radiopaque marker. | 18,952,311 |
[Contribution of exercise and diet in the management of knee osteoarthritis in the obese]. | Our objective was to determine whether exercise and weight loss are more effective either separately or in combination, in improving pain and physical function in obese adults with moderate knee osteoarthritis (OA). Forty-five obese adults, with a body mass index greater than 35 kg/m2 or 30<or=BMI<35 associated to at least one cardiovascular risk factor, suffering from knee pain with evident radiographic signs of knee OA, were involved in our study. All patients were evaluated at baseline and at the end of the study. The assessment parameters were weight loss, the bioelectric impedance analysis, pain, six-minute walk distance, cardiovascular parameters, and muscular strength. The physical function was measured with the Womac and the Lequesne indexes. Patients were randomized into four groups, a control group (G1), exercise only group (G2), diet plus exercise group (G3) and diet only group (G4). There was no difference between the four groups at baseline. Significant improvement of function (Womac) was noticed in groups performing exercise only (G2) (26%), diet plus exercise (G3) (37.89%) and diet only (G4) (18.34%). We also noticed an improvement in pain in G2 (p=0.04), G3 (p<0.001) and G4 (p=0.02). The improvement of quadriceps strength was noted only in G2 (p=0.01) et G3 (p=0.001) without any change in control group and diet only group (G4). The improvement of cardiovascular parameters was observed only in G2 and G3. Weight loss, decreased BMI and waist circumference was more important in diet plus exercise group (G3). The combination of weight loss and exercise provide better improvements in physical function and pain in obese adults with knee OA compared with either intervention alone. Exercise used alone or associated to dietary provides better improvements in physical capacity and muscle strength. | 18,952,312 |
Payments for health care and its effect on catastrophe and impoverishment: experience from the transition to Universal Coverage in Thailand. | Equitable health financing was embodied in the reform strategies of Thailand's health care system when the country moved towards implementing the Universal Coverage (UC) policy in 2001. This study aimed to measure the pattern of household out-of-pocket payments for health care and to examine the financial catastrophe and impoverishment due to such payments during the transitional period (pre- and post-Universal Coverage policy implementation) in Thailand. This study used the nationally representative Socioeconomic Surveys in 2000 (pre-UC), 2002, and 2004 (post-UC), which contained data from 24747, 34758 and 34843 individual households, respectively. The proportion of out-of-pocket payments for health care as a share of household living standards among Thai households shows a decreasing pattern during the observed period. Moreover, the incidence and intensity of catastrophic payments for health care decline from the pre-UC to post-UC period. The distribution of incidence and the intensity of catastrophic payments for health care across quintiles also indicate that the lower quintile group (1st and 2nd quintiles) incurs lower catastrophic health care payments compared to the higher quintile group. The UC policy is also effective in preventing impoverishment due to out-of-pocket payments for health care since both the poverty headcount and poverty gap decline from the pre-UC to post-UC period. This study provides important evidence that the UC policy implementation is a valuable social protection and safety net strategy that contributes to the prevention of financial catastrophe and impoverishment due to out-of-pocket payments for health care. In conclusion, the UC policy in Thailand achieves one of the goals of improving the health system through equitable health care financing by reducing financial catastrophe and impoverishment due to out-of-pocket payments for health care. | 18,952,336 |
The evolving concept of health literacy. | The relationship between poor literacy skills and health status is now well recognized and better understood. Interest in this relationship has led to the emergence of the concept of health literacy. The concept has emerged from two different roots - in clinical care and in public health. This paper describes the two distinctive concepts that reflect health literacy, respectively, as a clinical "risk", or a personal "asset". In the former case a strong science is developing to support screening for poor literacy skills in clinical care and this is leading to a range of changes to clinical practice and organization. The conceptualization of health literacy as an asset has its roots in educational research into literacy, concepts of adult learning, and health promotion. The science to support this conceptualization is less well developed and is focused on the development of skills and capacities intended to enable people to exert greater control over their health and the factors that shape health. The paper concludes that both conceptualizations are important and are helping to stimulate a more sophisticated understanding of the process of health communication in both clinical and community settings, as well as highlighting factors impacting on its effectiveness. These include more personal forms of communication and community based educational outreach. It recommends improved interaction between researchers working within the two health literacy perspectives, and further research on the measurement of health literacy. The paper also emphasizes the importance of more general strategies to promote literacy, numeracy and language skills in populations. | 18,952,344 |
Objective assessment of cardiopulmonary resuscitation skills of 10-11-year-old schoolchildren using two different external chest compression to ventilation ratios. | To objectively evaluate how effectively children can perform cardiopulmonary resuscitation CPR) 2 months after a single, 2h training session and establish whether or not their performance is affected by the ratio of external chest compressions to ventilations used. Eighty-five schoolchildren aged 10-11 years old were given a 2-h CPR training programme. After 2 months they were randomised into two groups and asked to perform CPR on a resuscitation skills reporter manikin for 3min at a ratio of 30:2 followed by 5min rest, then for 3min at 15:2 (or vice versa). Chest compression depths and ventilation volumes were recorded on a laptop computer and analysed using the Hills and Armitage crossover trial design. The school children were found to be capable of performing effective CPR 2 months after a single training session. In both groups the percentage of chest compressions, of depth recommended by current CPR guidelines, was greater when the 15:2 ratio was being used (P<0.001). The average chest compression depth was significantly greater when the children were performing CPR at a ratio of 15:2 (P<0.001). The compression to ventilation ratio used did not affect the average volume or percentage of effective ventilations given. However, in both groups, the ventilation variables showed enhanced performance during the second period of CPR. Children as young as 10-11 years are capable of performing effective CPR after a single, 2h training session in cardiopulmonary resuscitation given in school. This age group are able to achieve greater depth of chest compressions, when using a ratio of 15:2 rather than 30:2. | 18,952,356 |
Digalloylresveratrol, a new phenolic acid derivative induces apoptosis and cell cycle arrest in human HT-29 colon cancer cells. | Digalloylresveratrol (DIG) is a new synthetic ester of the naturally occurring polyhydroxyphenolic substances gallic acid and resveratrol which both exert anti-cancer activity in a number of tumor cell lines. The aim of the study was to identify the biochemical effects of DIG in HT-29 human colon cancer cells. DIG induced dose-dependently apoptosis after treatment for 72 h (40 microM DIG caused apoptosis in 45% of cells). DIG led to a substantial imbalance of deoxyribonucleoside triphosphates (dNTPs), the products of the enzyme ribonucleotide reductase (RR) and directly inhibited RR as it significantly reduced the incorporation of (14)C-labeled cytidine into the DNA of tumor cells. Furthermore, DIG affected the cell division and inhibited the transition from S to G2/M phase of the cell cycle. In contrast to resveratrol or gallic acid, DIG did not inhibit cyclooxygenases I and II. When HT-29 cells were simultaneously treated with DIG and 5-FU, the standard chemotherapeutic substance for colon cancer, additive growth inhibitory effects could be observed. With respect to the various biochemical and anti-proliferative effects of DIG in HT-29 cells, we regard DIG as a potential candidate for future treatment options of colon cancer and conclude that further preclinical and in vivo studies are warranted. | 18,952,370 |
The treatment of hand burns. | In more than 80% of all burns, the hand is involved. Even if a burned hand does not play a major role for the survival of a patient, its function and aesthetic appearance are of utmost importance for the re-integration into society and professional life. Adequate treatment demands a number of major decisions: necessity of an escharotomy in the early post-traumatic phase, the timing of surgery and the type of wound coverage, as well as immobilization and rehabilitation. Rapid wound closure is of utmost importance, but infection control and the preservation of active and passive motion are also essential for optimal recovery of the injured hand. The treatment of hand burns requires the interdisciplinary teamwork of surgeons, physio- and occupational therapists, psychologists, motivated health care personnel and consequent treatment strategies. | 18,952,379 |
[Hyperreactive malarial splenomegaly: three clinical cases and literature review]. | Hyperreactive malarial splenomegaly (HMS) is the chronic stage of a long-term stimulation of the immune system secondary to plasmodial infections, more frequently in genetically predisposed patients. HMS is a leading cause of large tropical splenomegaly in endemic zones but has been described in immigrants from Africa and in some European expatriates living in endemic countries. Diagnostic criteria include: long-term stay in a endemic zone, often large splenomegaly, high IgM titer, high antiplasmodial antibody titer, regression by at least 40% of splenomegaly six months after curative antimalarial treatment. In tropical settings, B-cell lymphoma and splenic lymphoma are the main differential diagnoses, which may be identified by a clonality analysis. Recent studies suggest that HMS can be treated by a short-term antimalarial therapy as long as the patient resides out of a malarial endemic country. | 18,952,389 |
Aseptic loosening of total hip arthroplasty: preliminary genetic investigation. | Femoral and acetabular loosening can be attributed different factors, but the causes and mechanism of early failure are still obscure. The objective of this study was to investigate the relationship between gene polymorphisms and early implant failure. Fifty-eight patients older than 50 years was recruited for analysis of MMP-1 promoter polymorphisms in early osseointegrated implant failure. The results showed in control group a frequency of 20.97% of 2G allele and 67.74% the genotype 1G/1G whereas, in the test group, a frequency of 83.33% of 2G allele and 66.66% the genotype 2G/2G. These results indicate that the polymorphism in the promoter of the MMP-1 gene could be a risk factor for early implant failure of total hip arthroplasty. | 18,952,406 |
Compostable cutlery and waste management: an LCA approach. | The use of disposable cutlery in fast food restaurants and canteens in the current management scenario generates mixed heterogeneous waste (containing food waste and non-compostable plastic cutlery). The waste is not recyclable and is disposed of in landfills or incinerated with or without energy recovery. Using biodegradable and compostable (B&C) plastic cutlery, an alternative management scenario is possible. The resulting mixed homogeneous waste (containing food waste and compostable plastic cutlery) can be recycled through organic recovery, i.e., composting. This LCA study, whose functional unit is "serving 1000 meals", shows that remarkable improvements can be obtained by shifting from the current scenario to the alternative scenario (based on B&C cutlery and final organic recovery of the total waste). The non-renewable energy consumption changes from 1490 to 128MJ (an overall 10-fold energy savings) and the CO(2) equivalents emission changes from 64 to 22 CO(2) eq. (an overall 3-fold GHG savings). | 18,952,413 |
Studies of the metabolic stability in cells of 5-(trifluoroacetyl)thiophene-2-carboxamides and identification of more stable class II histone deacetylase (HDAC) inhibitors. | 5-(Trifluoroacetyl)thiophene-2-carboxamides were found to be potent and selective class II HDAC inhibitors. This paper describes their further development and the investigation on the cause for the lack of cell-based activity. A rapid screening assay was set up which enabled the identification of more metabolic stable compounds as potent and selective class II HDAC inhibitors. | 18,952,417 |
A Spanish sporadic case of deafness-dystonia (Mohr-Tranebjaerg) syndrome with a novel mutation in the gene encoding TIMM8a, a component of the mitochondrial protein translocase complexes. | Mohr-Tranebjaerg syndrome is a rare X-linked condition characterized by the association of dystonia and progressive postlingual sensorineural hearing impairment. Here we report the clinical and genetic findings in a Spanish patient with MTS carrying a novel mutation in the DDP1 (deafness-dystonia peptide 1) gene, which encodes TIMM8a, a component of the mitochondrial protein translocation system. The phenotypic variability observed in patients with Mohr-Tranebjaerg syndrome suggests the involvement of modifier factors which may modulate the clinical manifestations of the syndrome. | 18,952,432 |
Substituted hippurates and hippurate analogs as substrates and inhibitors of peptidylglycine alpha-hydroxylating monooxygenase (PHM). | Peptidyl alpha-hydroxylating monooxygenase (PHM) functions in vivo towards the biosynthesis of alpha-amidated peptide hormones in mammals and insects. PHM is a potential target for the development of inhibitors as drugs for the treatment of human disease and as insecticides for the management of insect pests. We show here that relatively simple ground state analogs of the PHM substrate hippuric acid (C(6)H(5)-CO-NH-CH(2)-COOH) inhibit the enzyme with K(i) values as low as 0.5microM. Substitution of sulfur atom(s) into the hippuric acid analog increases the affinity of PHM for the inhibitor. Replacement of the acetylglycine moiety, -CO-NH-CH(2)-COOH with an S-(thioacetyl)thioglycolic acid moiety, -CS-S-CH(2)-COOH, yields compounds with the highest PHM affinity. Both S-(2-phenylthioacetyl)thioglycolate and S-(4-ethylthiobenzoyl)thioglycolic acid inhibit the proliferation of cultured human prostate cancer cells at concentrations >100-fold excess of their respective K(i) values. Comparison of K(i) values between mammalian PHM and insect PHM shows differences in potency suggesting that a PHM-based insecticide with limited human toxicity can be developed. | 18,952,446 |
Prospective randomized comparison of left atrial and biatrial radiofrequency ablation in the treatment of atrial fibrillation. | The aim of this study was to compare, in patients with permanent atrial fibrillation (AF), the efficacy and safety of left atrial ablation with that of a biatrial procedure and to assess the risk factors for late failure of sinus rhythm restoration. Between January 2004 and January 2007, 299 consecutive patients underwent the radiofrequency ablation procedure for AF associated with concomitant cardiac surgery. According to a prospective, open, and randomized trial, 149 patients underwent left atrial plus cavotricuspid isthmus ablation (left atrial group), while 150 patients underwent biatrial ablation (biatrial group). The postoperative and mid-term follow-up results were compared between the two groups. Both univariate and multivariate analyses were used to assess the risk factors for late recurrence of AF. There were seven in-hospital deaths (2.3%), including two in the left atrial group (1.3%) and five in the biatrial group (3.3%), and there were no differences in the incidence of the mortality and complications during the postoperative and follow-up periods between the groups. At discharge, sinus rhythm was maintained in 77.1% of the patients, including 78.2% of those in the left atrial group and 75.9% in the biatrial group (p=0.68). Follow-up was completed in 97% of the patients, with a mean time of 28+/-5 months. At the latest follow-up, two deaths occurred in the biatrial group. Sinus rhythm was documented in 237 (85.0%) out of all the patients, including 85.2% (121/142) in the left atrial group and 84.1% (116/138) in the biatrial group patients (p=0.87). Using a multivariate analysis, a left atrial diameter of >/=80 mm (p=0.02) was an independent predictor for a late recurrence of AF. Both the left atrial combined with cavotricuspid isthmus ablation and biatrial maze procedure is safe and effective in treating patients with AF, with an acceptable sinus conversion rate, mortality and morbidity. A left atrial dimension of >/=80 mm was a significant predictor for a late recurrence of AF. | 18,952,450 |
Bioprosthetic replacement of the ascending thoracic aorta: what are the options? | Increasing patient age and improved durability of latest generation bioprostheses have stimulated the use of bioprosthetic devices in the setting of ascending aortic replacement as an alternative to mechanical valved conduits or aortic valve-sparing procedures. We performed an English literature review to assess different surgical options that have been described for bioprosthetic replacement of the ascending aorta. Reported options include: (1) composite valved conduits using a stented bioprosthesis; (2) composite valved conduits using a stentless bioprosthesis; (3) total xenopericardial valved conduits. Composite valved grafts using stented bioprostheses offer a safe and durable option for bioprosthetic replacement of the ascending aorta. Other options are of more recent use and await medium-term results. | 18,952,452 |
Expression of BCL10 is significantly associated with the progression and prognosis of oral squamous cell carcinomas in Taiwan. | This study used an immunohistochemical technique to examine the expression of BCL10 in 93 specimens of oral squamous cell carcinoma (OSCC) and 21 specimens of normal oral mucosa (NOM). We found a significant correlation between the higher mean BCL10 labeling index (LI) and OSCCs at the tongue, with larger tumor size, with positive lymph node metastasis, with more advanced clinical stages, or with recurrence (all p-values=0.000). Positive lymph node metastasis (p=0.044) and BCL10 LI>50% (p=0.037) were identified as independent unfavorable prognosis factors by multivariate analyses with Cox regression model. The Kaplan-Meier curve showed that OSCC patients with a BCL10 LI>50% had a significantly poorer cumulative survival than those with a BCL10 LI<50% (log-rank test, p<0.00001). We conclude that the BCL10 LI in OSCC samples can predict the progression of OSCCs and the survival of OSCC patients. | 18,952,491 |
Enhanced frequencies of CD14++CD16+, but not CD14+CD16+, peripheral blood monocytes in severe asthmatic patients. | CD16+ monocytes are expanded in various inflammatory conditions. Recently it was reported that CD16+ monocytes can be divided into two subsets with contrasting potential of modulating inflammatory responses, namely CD14++CD16+ and CD14+CD16+ monocytes. Here, we characterized and quantified CD14++CD16+ and CD14+CD16+ monocyte subsets in asthmatic patients in the context of severity of disease and different treatment options. Subjects included seventeen severe asthmatics and eighteen moderate asthmatics treated with moderate-to-high doses of inhaled glucocorticosteroids (GCS), twenty nine steroid-naive mild asthmatics and fifteen healthy controls. First, we demonstrated that CD14++CD16+ monocytes, in contrast to CD14+CD16+ monocytes, present significantly higher expression of anti-inflammatory molecule CD163. The frequency of CD14++CD16+, but not CD14+CD16+ monocytes, was significantly higher in patients with severe asthma as compared to mild and moderate asthmatics. However, the frequency of both CD16+ monocyte subsets did not correlate directly with exhaled nitric oxide levels. Short-term administration of oral GCS in patients with exacerbations resulted in a preferential decrease of CD14+CD16+ monocytes. Our study indicates that CD14++CD16+ and CD14+CD16+ monocyte subsets in asthmatics are differentially modulated by both the inflammatory process and GCS treatment. | 18,952,503 |
grlA and gyrA mutations and antimicrobial susceptibility in clinical isolates of ciprofloxacin- methicillin-resistant Staphylococcus aureus. | To determine grlA and gyrA mutations in ciprofloxacin- methicillin-resistant Staphylococcus aureus isolates and their susceptibility to current antimicrobials, including a newer fluoroquinolone gatifloxacin, glycopeptides vancomycin, teicoplanin and oxazolidinone linezolid. A total of 56 methicillin-resistant S. aureus (MRSA) isolates were collected during 2003-2006 from inpatients of Süleyman Demirel University Hospital. The isolates were confirmed to be MRSA by the production of coagulase, showing resistance against cefoxitin and having the mecA gene and tested by disk diffusion for susceptibility to vancomycin, teicoplanin and linezolid. The minimum inhibitory concentrations (MICs) of ciprofloxacin and gatifloxacin were measured using the E-test. The quinolone resistance determining regions (QRDRs) of isolates were amplified by PCR and mutations in grlA and gyrA genes were identified by direct sequencing. Sequencing data revealed that 96% of our isolates had mutations in both grlA and gyrA genes. Among these, the grlA mutation of Ser-80-Phe or Tyr and the gyrA mutation of Ser-84-Leu were the most dominant ones being detected in 50 (89%) and 40 (71%) isolates, respectively. Although 96% of isolates were highly resistant to ciprofloxacin (MIC, >or=32 mg/l), only 54% of ciprofloxacin-resistant MRSA isolates were resistant to gatifloxacin and exhibited lower-level resistance (MIC, <or=6 mg/l). Of the isolates tested, 46% were found to be susceptible to gatifloxacin (MIC, <or=0.5 mg/l). Full susceptibility was observed for vancomycin, teicoplanin and linezolid. This study provided information on grlA and gyrA mutations and current antimicrobial susceptibility in clinical MRSA isolates. The results indicated that gatifloxacin is still effective against MRSA isolates and might be useful for treatment of less serious MRSA infections but careful monitoring of susceptibility is required. | 18,952,518 |
Smoking and drinking habits are important predictors of Helicobacter pylori eradication. | The aim of the study was to evaluate the effect of smoking and drinking habits, in separate and joint analyses, on the efficacy of H. pylori eradication. A total of 250 patients were recruited. They were treated with a 7-day course of omeprazole, amoxicillin, tinidazole (OAT), omeprazole amoxicillin, clarithromycin (OAC) or omeprazole, clarithromycin, tinidazole (OCT). The efficacy of H. pylori eradication was tested with a CLO-test and histology 4 weeks after the completion of antibacterial therapy. Drinking was found not to affect the efficacy of H. pylori eradication in any therapeutic group, while smoking decreased it in the OAC group (smokers 69.6%, non-smokers 94.3%, p=0.006). In the OAT treated group H. pylori eradication rate was lower in smokers-non-drinkers than in smokers-drinkers and non-smokers-non-drinkers (38.9% vs 83.2% and 70.0%, p=0.002 and p=0.034, respectively), while in the OAC treated group, smokers-non-drinkers had lower eradication efficacy than non-smokers-drinkers and non-smokers-non-drinkers (59.1% vs 100% and 91.3%, p=0.01 and p=0.012, respectively). In the OCT treated group, differences between subgroups were not significant. Smoking and drinking habits when analyzed jointly are more useful to predict the outcome of H. pylori eradication than when analyzed separately. | 18,952,538 |
Treatment of patients with myeloma with comorbid conditions: considerations for the clinician. | Patients with multiple myeloma (MM) frequently present with serious comorbidities such as renal impairment and/or diabetes. Treatment of these patient subsets poses a greater challenge: renal dysfunction can alter drug clearance leading to increased toxicity, and commonly used regimens can induce or exacerbate hyperglycemia. In recent years, novel targeted therapies have broadened and improved treatment options for all patients with MM. With these advancements, clinical trials are beginning to report benefit in patients with renal impairment. Furthermore, steroid-sparing and steroid-free regimens have proven highly efficacious and are predicted to improve options for patients with diabetes. This review will highlight recent trials evaluating novel regimens that promise to improve the standard of care for patients with MM with significant comorbidity. | 18,952,546 |
Unraveling the biologic and clinical complexities of HER2. | It has been over 20 years since the discovery of the human epidermal growth factor receptor 2 (HER2), a tyrosine kinase receptor that is a potent oncoprotein in breast and other cancers and has become an opportune target for therapy. HER2 plays a critical role in normal development, forming homodimers or heterodimers with other HER family members and triggering downstream signaling cascades controlling proliferation, cell survival, and apoptosis. However, amplification of the HER2 gene in cancer cells results in overexpression of HER2 receptors on the cell surface, leading to excessive and dysregulated signaling. HER2-driven signaling also upregulates transcription factors that act on the HER2 promoter, increasing its expression. In breast cancer, HER2 is gene amplified in 20%-25% of primary tumors and is associated with a more aggressive phenotype and poorer prognosis. The key role HER2 plays in tumorigenesis makes it an ideal target for therapy. Trastuzumab, a monoclonal antibody against HER2, inhibits downstream signaling and has proven to be effective against HER2-overexpressing metastatic breast cancer both as a single agent and in combination with chemotherapy. Seminal clinical trial data also show that the use of adjuvant trastuzumab in combination with chemotherapy or as a single agent after chemotherapy significantly increases disease-free and overall survival. Lapatinib, a dual tyrosine kinase inhibitor against HER1 and HER2, has been approved in combination with capecitabine for HER2-overexpressing advanced or metastatic breast cancer, which has progressed following previous anthracycline, taxane, and trastuzumab therapy. Other HER2-targeting strategies are also under active investigation. | 18,952,552 |
Extended adjuvant endocrine therapy in breast cancer: current status and future directions. | Women with hormone receptor-positive breast cancer have traditionally been treated with 5 years of adjuvant tamoxifen to reduce their risk of subsequent recurrent disease. Among those who experience subsequent disease recurrence, the majority do so after 5 years, suggesting that longer durations of endocrine therapy might be beneficial. Two options tested include longer tamoxifen and, in postmenopausal women, a switch to an aromatase inhibitor (AI). In the National Cancer Institute of Canada Cooperative Trials Group MA.17 trial, we tested the AI letrozole given to postmenopausal women for 5 years after tamoxifen as extended adjuvant therapy because of its efficacy in patients with advanced breast cancer in progression on previous tamoxifen. The first interim analysis (median, 2.4 patient years) showed substantial benefits from letrozole, and all patients were unblinded and offered the option of letrozole. Despite two thirds of the patients crossing over to letrozole, an intent-to-treat analysis at 54 months' follow-up continued to demonstrate the strong beneficial effect of extended adjuvant letrozole. Furthermore, significant benefit was demonstrated among patients who had been randomized to placebo but elected to take letrozole after a prolonged washout from previous tamoxifen (late extended adjuvant therapy). A trial examining the merits of > 5 years of treatment with an AI, MA.17R, is ongoing, as are a number of other trials of duration of therapy. This article reviews results from MA.17 and the design of these trials of duration. | 18,952,554 |
Retrospective evaluation of clinical outcomes in patients with HER2-positive advanced breast cancer progressing on trastuzumab-based therapy in the pre-lapatinib era. | Patients with HER2-positive breast cancer whose disease has become resistant to the anti-HER2 monoclonal antibody trastuzumab can benefit from lapatinib, a dual epidermal growth factor receptor/HER2 tyrosine kinase (TK) inhibitor. Before the availability of this compound, trastuzumab was often continued beyond disease progression, usually in addition to further chemotherapy, an approach which was not based on randomized studies. We sought to retrospectively compare the clinical outcomes of patients who, upon progression during an initial trastuzumab-based regimen, stopped or continued trastuzumab in addition to further chemotherapy. From the clinical records of 407 patients with HER2-positive advanced breast cancer, we identified 279 patients progressing during an initial trastuzumab-based treatment. Of these patients, 83 continued trastuzumab in addition to chemotherapy, and 112 received chemotherapy alone. We found no difference in response rate (28% vs. 30%; P = .5), median time to second tumor progression (8.4 months vs. 7 months; P = .24), or median postprogression survival (20.6 months and 15.4 months; P = .29) according to whether patients continued or stopped trastuzumab. At multivariate analysis, continuation of trastuzumab was associated with a statistically insignificant trend toward reduced risk of second progression (hazard ratio, 0.753; P = .08). Patients with HER2-positive advanced breast cancer developing tumor progression during an initial trastuzumab-based regimen did not seem to benefit significantly from the continuation of trastuzumab in addition to chemotherapy. For these patients, there is evidence from a large randomized trial that effective HER2 targeting can be accomplished by inhibiting the HER2 TK activity with lapatinib. | 18,952,558 |
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