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Computational simulation of spontaneous bone straightening in growing children.
Periosteal surface pressures have been shown to inhibit bone formation and induce bone resorption, while tensile strains perpendicular to the periosteal surface have been shown to inhibit bone resorption and induce new bone deposition. A new computational model was developed to incorporate these experimental findings into simulations of spontaneous bone straightening in children with congenital posteromedial bowing of the tibia. Three-dimensional finite element models of the periosteum were used to determine the relationships between the defect angle and the distribution of bone surface pressures and strains due to growth-generated tensile strains in the periosteum. These relationships were incorporated into an iterative simulation to model development of a growing, bowed tibia with an initial defect angle of 27 degrees. When periosteal loads were included in the simulation, the defect angle decreased to 10 degrees after 2 years, and the bone straightened by an age of 25 years. When periosteal loads were not included in the simulation, the defect angle decreased to 23 degrees after 2 years, and a defect angle of 9 degrees remained at an age of 25 years. A "modeling drift" bone apposition/resorption pattern appeared only when periosteal loads were included. The results suggest that periosteal pressures and tensile strains induced by bone bowing can accelerate the process of bone straightening and lead to more complete correction of congenital bowing defects. Including the mechanobiological effects of periosteal surface loads in the simulations produced results similar to those seen clinically, with rapid straightening during the first few years of growth. | {
"pile_set_name": "PubMed Abstracts"
} |
Vinyl-vinyl coupling on late transition metals through C-C reductive elimination mechanism. A computational study.
A detailed density functional study was performed for the vinyl-vinyl reductive elimination reaction from bis-sigma-vinyl complexes [M(CH=CH(2))(2)X(n)]. It was shown that the activity of these complexes decreases in the following order: Pd(IV), Pd(II) > Pt(IV), Pt(II), Rh(III) > Ir(III), Ru(II), Os(II). The effects of different ligands X were studied for both platinum and palladium complexes, which showed that activation barriers for C-C bond formation reaction decrease in the following order: X = Cl > Br, NH(3) > I > PH(3). Steric effects induced either by the ligands X or by substituents on the vinyl group were also examined. In addition, the major factors responsible for stereoselectivity control on the final product formation stage and possible involvement of asymmetric coupling pathways are reported. In all cases DeltaE, DeltaH, DeltaG, and DeltaG(aq) energy surfaces were calculated and analyzed. The solvent effect calculation shows that in a polar medium halogen complexes may undergo a reductive elimination reaction almost as easily as compounds with phosphine ligands. | {
"pile_set_name": "PubMed Abstracts"
} |
Chasing the genes that control resistance to gastrointestinal nematodes.
The host-protective immune response to infection with gastrointestinal (GI) nematodes involves a range of interacting processes that begin with recognition of the parasite's antigens and culminate in an inflammatory reaction in the intestinal mucosa. Precisely which immune effectors are responsible for the loss of specific worms is still not known although many candidate effectors have been proposed. However, it is now clear that many different genes regulate the response and that differences between hosts (fast or strong versus slow or weak responses) can be explained by allelic variation in crucial genes associated with the gene cascade that accompanies the immune response and/or genes encoding constitutively expressed receptor/signalling molecules. Major histocompatibility complex (MHC) genes have been recognized for some time as decisive in controlling immunity, and evidence that non-MHC genes are equally, if not more important in this respect has also been available for two decades. Nevertheless, whilst the former have been mapped in mice, only two candidate loci have been proposed for non-MHC genes and relatively little is known about their roles. Now, with the availability of microsatellite markers, it is possible to exploit linkage mapping techniques to identify quantitative trait loci (QTL) responsible for resistance to GI nematodes. Four QTL for resistance to Heligmosomoides polygyrus, and additional QTL affecting faecal egg production by the worms and the accompanying immune responses, have been identified. Fine mapping and eventually the identification of the genes (and their alleles) underlying QTL for resistance/susceptibility will permit informed searches for homologues in domestic animals, and human beings, through comparative genomic maps. This information in turn will facilitate targeted breeding to improve resistance in domestic animals and, in human beings, focused application of treatment and control strategies for GI nematodes. | {
"pile_set_name": "PubMed Abstracts"
} |
Mobile iron nanoparticle and its role in the formation of SiO2 nanotrench via carbon nanotube-guided carbothermal reduction.
The detailed role of iron nanoparticles (NPs) involved with the formation of SiO2 nanotrenches is revealed. The physical movements of iron NPs, such as levitation and adsorption, turn out to be responsible for the initiation of carbothermal reduction (C (carbon nanotube, s) + SiO2(s) <--> SiO(g) + CO(g)), which results in SiO2 nanotrenches that are fully guided by carbon nanotubes. Under the chemical vapor deposition condition with 0.1% of O2 gas, iron NPs are liberally levitated from SiO2/Si substrate then adsorbed on the sidewalls of carbon nanotubes. Depending on the numbers of iron NPs attached to carbon nanotubes, two different types of nanotrenches are determined. When multiple iron NPs are assembled on carbon nanotubes and involved in carbothermal reduction, aligned nanohole type of nanotrenches is produced (Type I). On the contrary, when single iron NPs initiate the carbothermal reduction, nanotrenches having smooth pathways and high shoulders are commonly formed (Type II). | {
"pile_set_name": "PubMed Abstracts"
} |
Differential effects of post-implantation time on potassium- versus D-amphetamine-evoked dopamine overflow in the striatum of F344 rats.
Effects of post-implantation time on potassium (K+)- versus D-amphetamine (D-AMPH)-evoked striatal dopamine (DA) overflow were measured using microdialysis in freely moving young and aged Fischer 344 rats. In one group, samples were collected on the day of probe insertion (Day 1 group). In a second group, samples were collected 24 h after probe insertion (Day 2 group). While analyses revealed no significant differences between the two age groups, the 100 mM K+ stimulus evoked a significantly greater amount of DA overflow in the Day 1 group compared to the Day 2 group. The decrease in 3,4-dihydroxyphenylacetic acid (DOPAC) produced by K+ stimulation was not influenced by post-implantation time. The effect of the 250 microM D-AMPH stimulus on DA overflow did not differ between the Day 1 and Day 2 groups, nor did the decrease in DOPAC that accompanied D-AMPH stimulation. These results support the hypothesis that under some stimulus conditions, post-implantation time is an important variable in microdialysis studies. | {
"pile_set_name": "PubMed Abstracts"
} |
An aptasensor for detection of potassium ions based on RecJ(f) exonuclease mediated signal amplification.
An electrochemical biosensor for potassium has been developed combining specific potassium-aptamer binding and RecJf exonuclease mediated signal amplification. Generally, the DNA probe with a stem-loop structure containing an anti-K(+) aptamer sequence is designed and modified on a gold electrode. K(+) can specifically bind to the aptamer and a G-quadruplex structure forms, which breaks the original stem-loop structure. The induced single-stranded 5' end can be further digested by RecJf exonuclease, releasing K(+) which can bind to another DNA probe on the electrode. After cycles of RecJf exonuclease cleavage initiated by K(+), the electrochemical signal intensity is significantly decreased, and can be used to determine the concentration of K(+). This aptasensor shows high sensitivity, selectivity as well as excellent stability and accuracy, which provides possibilities for further applications of K(+) assay in clinical diagnosis. | {
"pile_set_name": "PubMed Abstracts"
} |
Analysis of foraminifera assemblages and sediment geochemical properties to characterise the environment near Araçá and Saco da Capela domestic sewage submarine outfalls of São Sebastião Channel, São Paulo State, Brazil.
Superficial bottom samples were collected near diffusers of domestic sewage submarine outfalls at Araçá and Saco da Capela, São Sebastião Channel, Brazil. The goal of this study was to investigate the distribution and composition of live benthic foraminifera assemblages and integrate the results obtained with geochemical analyses to assess human-induced changes. According to the results obtained no environmental stress was observed near the Saco da Capela submarine outfall diffusers. The foraminifera assemblage is characterised by species typical of highly hydrodynamic environments, with well-oxygenated bottom waters and low nutrient contents. In contrast, near Araçá submarine outfall, organic enrichment was denoted by high phosphorus, sulphur and, to a lesser extent, total organic carbon content. Harmful influences on foraminifera could be identified by low richness and specific diversity, as well as the predominance of detritivore feeder species, which are associated with higher organic matter flux and low oxygen in the interstitial pore water. | {
"pile_set_name": "PubMed Abstracts"
} |
New strip immunoblot for the confirmation of HTLV-I/II infection.
In The Netherlands, anti-human T-cell lymphotropic virus type I (HTLV-I) blood donor screening became mandatory in January 1993. Donations reactive in the enzymelinked immunosorbent assay (ELISA) screening test are confirmed with Western blot analysis (WB). Only WB-positive or indeterminate blood donors are notified and retested by polymerase chain reaction (PCR) [1]. In accumulated data of the Dutch Blood Banks, only 2% of donors repeatedly positive in the anti-HTLV-I/II ELISA were WB-positive and all of these were also PCR-positive. However, 75% of the ELISA-positive blood donors have indeterminate WB results. In these cases the ELISA reactivities are nonspecific since all WB-indeterminate donors are negative in PCR [2]. Current WB confirmation thus leads to the notification and often to the deferral of many WB-indeterminate blood donors as well as to high costs for PCR testing, illustrating the need for a more specific serological confirmatory assay. The aim of our study was to evaluate a newly developed anti-HTLV-I/II Recombinant Immunoblot Assay (RIBA) to confirm samples reactive to screening tests with a special emphasis on the ability of this test to resolve WB-indeterminate results in blood donors, without compromising the sensitivity. | {
"pile_set_name": "PubMed Abstracts"
} |
Application of Alu-splice PCR on chromosome 21: DSCR1 and Intersectin.
Down syndrome (DS) is a major cause of mental retardation and congenital heart defects, with an overall incidence of one in 700 live births. DS is caused by increases in the amounts of a number of normal gene products, the exact number and identity of which are presently unknown. Elucidating the molecular basis of DS relies on the identification of the gene products whose augmentation by 50% or more causes symptoms of the disease. With the aim of contributing to the transcriptional map of human chromosome 21 and to identify new genes with potential involvement in DS, we developed a technique to isolate expressed sequences called Alu-splice PCR, which is very simple to perform and is independent of gene expression patterns. Putative exons are PCR amplified in genomic DNA by virtue of their proximity to Alu repeats using primers designed from splice-site consensus sequences in combination with specific Alu repeat primers. The Alu repeats, which are repetitive DNA elements found exclusively and at high frequency in the genomes of primates, impart the human specificity to the method. The splice-site consensus sequences were used to direct primers to exon boundaries. Using the Alu-splice technique, we have identified at least three new genes. We trapped an exon of DSCR1 (Down Syndrome Candidate Region 1) and two different exons of a gene called human Intersectin (ITSN). Presently, we are working with another novel trapped exon to identify the corresponding gene. The major advantage of Alu-splice PCR is that the technique can be readily established in any laboratory which has the basic facilities for molecular biology because no specialised materials or expertise is required. | {
"pile_set_name": "PubMed Abstracts"
} |
Endobronchial tuberculosis presenting as tumorous mass.
We report a case of an 18-year-old boy presenting with features of right middle lobe collapse. On bronchoscopy, a tumorous type of endobronchial tuberculosis was found to be obstructing the lumen of the right middle lobe bronchus. On treatment with anti-tuberculous drugs the growth resolved significantly within three months. The patient, however, developed mild stenosis of the airway. | {
"pile_set_name": "PubMed Abstracts"
} |
[Adult human retinal pigment epithelial cells - a potential source of cells for regeneration retina].
Retinal pigment epithelium (RPE) arises from neuroectoderm and plays a key role in support of photoreceptor functions. Several degenerative eye diseases, such as macular degeneration or retinitis pigmentosa, are associated with impaired RPE function that may lead to photoreceptor loss and blindness. RPE cell culture derived from adult human eyes autopsy could be an important source for transplantation to cure such retinal degenerative diseases. RPE cells subsequent isolation and maintenance in culture are described. Besides the results of immunocytochemical analysis that characterizes dedifferentiated state of cultured adult human RPE cells are given. Our findings demonstrate that mature human RPE cells have the capacity to express neural markers in response to conditions that promote dedifferentiation. | {
"pile_set_name": "PubMed Abstracts"
} |
Rate of false source attributions depends on how questions are asked.
Lindsay and Johnson (1989) and Zaragoza and Koshmider (1989) report evidence indicating that "eyewitness" subjects are much less likely to falsely claim to have seen information suggested to them verbally when they receive a source monitoring test than when they receive a recognition test requesting only identification of the seen information. The present study reports additional evidence that source misattributions are affected by the nature of the test. Intraub and Hoffman (1992) recently reported the results of a study in which subjects claimed to have seen pictures corresponding to scenes that had only been described in paragraphs they had read. With this paradigm, we found a similar effect using their test, but source confusions were reduced with a test patterned after the one used by Lindsay and Johnson. We attribute this difference in performance to the different decision criteria evoked by these two tests. | {
"pile_set_name": "PubMed Abstracts"
} |
Mineralocorticoid excess and inhibition of 11 beta-hydroxysteroid dehydrogenase in patients with ectopic ACTH syndrome.
11 beta-Hydroxysteroid dehydrogenase protects renal mineralocorticoid receptors from cortisol by converting cortisol to inactive cortisone. We hypothesize that 11 beta-dehydrogenase is inhibited by ACTH, providing a mechanism whereby cortisol induces hypokalaemic alkalosis in ectopic ACTH syndrome. The principal sources of plasma cortisone were assessed by selective venous catheterization with measurement of cortisol and cortisone by radioimmunoassays. The effect of ACTH on peripheral plasma cortisol/cortisone ratio was assessed in healthy volunteers during circadian rhythm, insulin induced hypoglycaemia, and infusions with exogenous ACTH or cortisol. In patients with Cushing's syndrome plasma cortisol/cortisone ratios were related to plasma potassium, corticosterone, and 11-deoxycorticosterone concentrations. Catheterization was performed in 24 patients with valvular or ischaemic heart disease. Cushing's syndrome patients included: 15 with pituitary adenoma; two with adrenal adenoma; and nine with ectopic ACTH secretion. Plasma cortisol/cortisone ratios were low in renal vein and high in hepatic vein. In healthy volunteers plasma cortisone increased during cortisol infusion but did not change with increases in endogenous or exogenous ACTH. Plasma cortisol/cortisone ratios were higher in ectopic ACTH syndrome than in other forms of Cushing's syndrome. However, the cortisol/cortisone ratio was no better a predictor of hypokalaemia than the levels of 11-deoxycorticosterone or corticosterone. Peripheral conversion of cortisol to cortisone occurs mainly in the kidney and is inhibited by ACTH. In ectopic ACTH syndrome the characteristic mineralocorticoid excess can be accounted for by a combination of increased secretion of cortisol, corticosterone and of 11-deoxycorticosterone and decreased inactivation of cortisol and corticosterone by 11 beta-dehydrogenase. | {
"pile_set_name": "PubMed Abstracts"
} |
Short- and long-term functional alterations of the skeletal muscle calcium release channel (Ryanodine receptor) by Suramin: apparent dissociation of single channel current recording and [3H]ryanodine binding.
The present study demonstrates the following characteristic suramin actions on the purified skeletal muscle calcium release channel in single-channel current recordings and [(3)H]ryanodine binding to HSR: 1) Suramin (0.3-0.9 mM) induced a concentration-dependent increase in the open probability (P(o) congruent with 0.9) at 20 to 100 microM Ca(2+) and an almost fully open channel at 1 mM Ca(2+) (P(o) = 0.95) with a marked shift to longer open states (tau(o)3/tau(o)4). Suramin increased the apparent calcium affinity to the activating high-affinity calcium binding sites and reduced the apparent magnesium affinity to the inhibitory low affinity Ca(2+)/Mg(2+) binding sites. 2) Channel activation by suramin and sulfhydryl oxidation was additive. 3) Suramin (0.9 mM) reversed the Ca-calmodulin-induced channel inhibition at 0.1 or 1 to 5 microM Ca-calmodulin. 4) The open probability of the suramin activated channel was almost completely inhibited by 10 mM Mg(2+) or Ca(2+) on short suramin exposure. Prolonged suramin exposure (30-60 min) resulted in a time-dependent, slow increase in P(o), with long open states of low frequency in the presence of 10 to 20 mM Mg(2+) or Ca(2+). 5) Magnesium induced inhibition of P(o) (IC(50) = 0.38 mM) and equilibrium [(3)H]ryanodine binding (IC(50) = 0.30 mM) agreed well in control channels, but were dissociated in the presence of 0.9 to 1.0 mM suramin (IC(50) = 0.82 mM versus 83 mM). [(3)H]ryanodine binding seemed to monitor predominantly the long-term alteration in channel function. 6) The multiple effects of suramin on channel function suggest an allosteric mechanism and no direct effects on binding of endogenous ligands involved in channel gating. | {
"pile_set_name": "PubMed Abstracts"
} |
Nasal obstruction following septorhinoplasty: how well does acoustic rhinometry work?
Septorhinoplasty aims to improve not only the esthetic appearance but also breathing function of the nose. Although the esthetic improvement can be judged by the patient and the surgeon easily, evaluation of nasal breathing is more complicated. Besides the subjective symptom scores given by the patient, some objective methods have been developed. One of the most widely used of these objective methods is acoustic rhinometry, which gives valuable information about the cross-sectional areas and volumes of the nasal airway as a function of distance from the nostril. Since the introduction of acoustic rhinometry, many papers were reported regarding its efficiency with some conflicting conclusions. Septorhinoplasty has the potential to narrow the nasal airway, especially if it includes lateral osteotomies and hump reduction. We aimed to evaluate the role of rhinoplasty on nasal obstruction with the help of subjective symptom scores and acoustic rhinometry. The study consisted of 26 patients who underwent septorhinoplasty. Before and after surgery, the symptom scores and findings of acoustic rhinometry were collected both before and after decongestion of the nasal mucosa. Symptom scores decreased on both sides, which were statistically significant (p < 0.05), however, the changes in cross-sectional areas of the nasal airway were not statistically significant (p > 0.05). The correlation between the symptom scores and acoustic rhinometry findings was not significant for all levels. The effect of septorhinoplasty on nasal airway and some important maneuvers to protect against nasal obstruction are discussed. | {
"pile_set_name": "PubMed Abstracts"
} |
Heterogeneous effect of an Emergency Department Expert Charting System.
We compare results from different modules (occupational exposure to blood and body fluids, low back pain, and fever in children) of the Emergency Department Expert Charting System. Each module of this electronic medical record provides real-time advice based on clinical guidelines embedded in the software. We used a staggered off-on-off interrupted time-series design with an intent-to-treat analysis to implement the Emergency Department Expert Charting System in a university hospital emergency department for the treatment of fever in children, low back pain, and occupational exposure to blood and body fluids. We measured the quality of documentation as the percentage of essential items contained in the medical record and discharge instructions, the percentage of appropriate testing and treatment decisions, median charges per patient visit, physician satisfaction by pre-experiment and postexperiment questionnaires, and patient satisfaction by telephone questionnaire. The Emergency Department Expert Charting System improved documentation rates for all modules. The Emergency Department Expert Charting System consistently improved the appropriateness of diagnostic testing and treatment decisions for patients with occupational exposure to blood and body fluids while decreasing median charges. For the low back pain and fever in children modules, improvements in appropriateness of testing and treatment were less consistent and did not result in a decrease in charges. Although physicians were generally supportive of the intervention, the physicians' use of the Emergency Department Expert Charting System and satisfaction with the modules were greatest with occupational exposure to blood and body fluids and least with fever in children. For each presenting complaint, mean patient satisfaction was highest during the Emergency Department Expert Charting System phase. The delivery of guidelines through an electronic medical record with background decision support improved documentation, patient care, and patient satisfaction, although effects were heterogeneous across presenting complaints. The optimal guideline implementation strategy likely varies with the nature of the clinical problem and the type of health care delivery setting. For selected problems, delivering guidelines in this format through the Internet holds great promise for modifying physician behavior and improving care (see http://www.needlestick.mednet.ucla.edu ). | {
"pile_set_name": "PubMed Abstracts"
} |
[Parkinson disease : how to improve the voice and the quality of life].
Parkinson disease is a progressive neurodegenerative disease affecting the basal ganglia and causing the degeneration of dopaminergic neurons. It is a chronic affection with a slow evolution characterized by motor dysfunctions. Considering voice and speech, 90 % of patients present problems affecting their communication, social skills and quality of life. Although L-dopa has some effect on motor performance, speech and voice do not improve. So, the applicability and efficacy of non-pharmacological treatment, based on therapy is to be considered for voice impairment. Today, voice therapy is being viewed as a therapeutic option to be prescribed early in the course of Parkinson disease that may potentially contribute to slowing of motor symptom progression. | {
"pile_set_name": "PubMed Abstracts"
} |
Rotator cuff regeneration using a bioabsorbable material with bone marrow-derived mesenchymal stem cells in a rabbit model.
Rotator cuff regeneration using tissue engineering techniques is a challenging treatment in elderly patients with irreparable rotator cuff tears. A polyglycolic acid sheet scaffold with seeded mesenchymal stem cells (MSCs) may enhance the expression of type I collagen products and increase the mechanical strength of the regenerated tendon in vivo. Controlled laboratory study. A surgically created defect of infraspinatus tendons of rabbits was reconstructed with 2 different materials, a polyglycolic acid (PGA) sheet alone (PGA group) (n = 34) and a PGA sheet seeded with autologously cultured MSCs (MSC group) (n = 34). The authors created a tendon defect model without embedding any graft as the control model (control group) (n = 34). The rabbits were sacrificed at 4, 8, and 16 weeks after the operation and then were histologically evaluated. The rabbits were also biomechanically evaluated by measuring the ultimate failure loads and Young's modulus at 4 and 16 weeks following implantation. In the MSC group, the fibrocartilage layers and Sharpey fibers were found regularly in the insertion site at 8 weeks compared with the PGA group. In control group, thin membranes with many fibroblasts arranged in an irregular pattern linked the end of the torn cuff to the bone without any Sharpey fibers and type I collagen. A large volume of type I collagen was found in comparison with type III collagen at 16 weeks in the MSC group, whereas type III collagen was more prevalent than type I in the PGA group. The tendon maturing score in the MSC group had higher values than the PGA and control groups at 8 and 16 weeks (mean values were 21.0 ± 0.89, 24.0 ± 2.53 in the MSC group; 16.7 ± 2.25, 21.3 ± 2.42 in the PGA group; and 10.2 ± 0.98, 12.2 ± 1.72 in the control group, respectively) (P < .05). The results of the mechanical analysis revealed that the regenerated tendons in the MSC group had better tensile strength than in the PGA and control groups at 16 weeks (mean values were 3.04 ± 0.54 in the MSC group, 2.38 ± 0.63 in the PGA group, and 1.58 ± 0.13 in the control group) (P < .05). Bone marrow-derived MSCs were able to regenerate tendon-bone insertions and the tendon belly, including the production of type I collagen, and increased the mechanical strength of the regenerated rotator cuff tendon. Rotator cuff regeneration using MSCs is a promising treatment for massive rotator cuff defects. | {
"pile_set_name": "PubMed Abstracts"
} |
Feline bone marrow transplantation: its use in FIV-infected cats.
The use of autologous and allogenic bone marrow transplantations (BMT) in FIV-infected and uninfected cats is a novel therapy for feline hematopoietic diseases and retroviral infections. A total of 13 specific pathogen-free (SPF) cats received either autologous or allogenic BMT and seven of these cats were also infected with FIV before autologous or allogenic BMT. All BMT recipients received total body irradiation of 900 cGy just before BMT. Two FIV-infected and four uninfected cats received autologous uninfected BM cells cryopreserved before BMT. Five infected and two uninfected cats received BM cells from allogenic uninfected donors (RBC-, MHC-, and cross-matched). MHC-matching was based on mixed leucocyte reaction (MLR) and the donor-recipient combination which was compatible by MLR analysis, was used in this study. Recipients were monitored for hematology, immunology, virology, and clinical signs. All FIV-infected and uninfected recipients of autologous BMT had complete engraftment with minimal complications. Uninfected recipients of allogenic BMT had a more severe clinical episode with slower rate of engraftment. None of these BMT groups had mortality. In contrast, only two of the five infected recipients of allogenic BMT survived for a significant period of time (23 and 50 weeks) and rest of the cats succumbed to transfusion reactions. Both infected BMT groups had persistent CD4/CD8 inversion, low CD4+ cell counts, and FIV infection of engrafted peripheral blood mononuclear cells (PBMC). Overall, successful autologous and allogenic BMTs were performed in FIV-free cats. All infected recipients of autologous BMT had compete engraftment and are currently alive, with thelongest survival time being over 1 year. Thus, BMT in combination with antiviral drug therapies may be an alternative therapy against retroviral infection. | {
"pile_set_name": "PubMed Abstracts"
} |
A comparative joint simulator study of the wear of metal-on-metal and alternative material combinations in hip replacements.
While total hip replacement represents the major success story in orthopaedic surgery in the twentieth century, there is much interest in extending even further, early in the twenty first century, the life of implants. Osteolysis has been identified as a major factor limiting the life of prostheses, with indications that fine polyethylene wear debris, generated primarily at the interface between the femoral head and the acetabular cup, promotes the process. There is therefore considerable interest in the introduction of alternative wear resistant systems to limit the deleterious effects of wear. These alternatives include ceramic-on-ceramic and metal-on-metal configurations and the present paper is primarily concerned with the latter. Some six pairs of new metal-on-metal implants of 36 mm diameter and four pairs of existing metal-on-metal implants of 28 mm diameter were tested in a ten-station hip joint simulator in the presence of a 25 per cent bovine serum solution. The implants were tested in the anatomical position to 5 x 10(6) cycles. The new heads and cups were manufactured from CoCrMo alloy with careful attention being paid to sphericity and surface finish of both components. The wear performance of the new and existing metal-on-metal total hip replacements have been evaluated and compared. The overall wear rates have then been compared with previously reported wear rates for a zirconia-on-polyethylene prosthesis of 22 mm diameter tested on the same simulator. The comparison is taken further by recalling published penetration data for metal-on-polyethylene implants of 22 and 28 mm diameter and converting these to volumetric wear rates. It was found that the heads and cups in metal-on-metal joints wore by almost equal amounts and that the opposing surfaces converged to similar surface roughness as the testing time increased. Steady state wear rates were generally achieved after 1-2 x 10(6) cycles. The mean long-term wear rates for the metal-on-metal prostheses were very low, being 0.36 mm3/10(6) cycles and 0.45 mm3/10(6) cycles for the new implants of 36 mm diameter and established implants of 28 mm diameter respectively. These wear rates compare with 6.3 mm3/10(6) cycles for zirconia-on-ultra-high molecular weight polyethylene tested on the same simulator and representative clinical values for metal-on-polyethylene of 36 mm3/year for heads of 22 mm diameter and a reported range of 60-180 mm3/year for 28 mm heads. These values do not translate directly into numbers of particles, since the metallic debris from metal-on-metal joints is very fine. The number of metallic particles may exceed the number of polyethylene wear particles from an otherwise similar metal-on-polyethylene joint by a factor of 10(3). A detailed discussion of the size and morphology of wear debris and tissue reaction to various forms of debris is beyond the scope of this paper, but the biological response to polymeric, metallic and ceramic wear debris forms a major subject for further study. The present investigation nevertheless confirms the potential of carefully designed and manufactured metal-on-metal total replacement joints for the treatment of diseased and damaged hips. | {
"pile_set_name": "PubMed Abstracts"
} |
Next generation prophylactic human papillomavirus vaccines.
The two licensed bivalent and quadrivalent human papillomavirus (HPV) L1 (the major papillomavirus virion protein) virus-like particle (VLP) vaccines are regarded as safe, effective, and well established prophylactic vaccines. However, they have some inherent limitations, including a fairly high production and delivery cost, virus-type restricted protection, and no reported therapeutic activity, which might be addressed with the development of alternative dosing schedules and vaccine products. A change from a three-dose to a two-dose protocol for the licensed HPV vaccines, especially in younger adolescents (aged 9-13 years), is underway in several countries and is likely to become the future norm. Preliminary evidence suggests that recipients of HPV vaccines might derive prophylactic benefits from one dose of the bivalent vaccine. Substantial interest exists in both the academic and industrial sectors in the development of second-generation L1 VLP vaccines in terms of cost reduction-eg, by production in Escherichia coli or alternative types of yeast. However, Merck's nonavalent vaccine, produced via the Saccharomyces cerevisiae production system that is also used for their quadrivalent vaccine, is the first second-generation HPV VLP vaccine to be available on the market. By contrast, other pharmaceutical companies are developing microbial vectors that deliver L1 genes. These two approaches would add an HPV component to existing live attenuated vaccines for measles and typhoid fever. Prophylactic vaccines that are based on induction of broadly cross-neutralising antibodies to L2, the minor HPV capsid protein, are also being developed both as simple monomeric fusion proteins and as virus-like display vaccines. The strong interest in developing the next generation of vaccines, particularly by manufacturers in middle-to-high income countries, increases the likelihood that vaccine production will become decentralised with the hope that effective HPV vaccines will be made increasingly available in low-resource settings where they are most needed. | {
"pile_set_name": "PubMed Abstracts"
} |
Nursing Home Physicians' Assessments of Barriers and Strategies for End-of-Life Care in Norway and The Netherlands.
Working conditions in nursing homes (NHs) may hamper teamwork in providing quality end-of-life (EOL) care, especially the participation of NH physicians. Dutch NH physicians are specialists or trainees in elderly care medicine with NHs as the main workplace, whereas in Norway, family physicians usually work part time in NHs. Thus, we aimed at assessing and comparing NH physicians' perspectives on barriers and strategies for providing EOL care in NHs in Norway and in The Netherlands. A cross-sectional study using an electronic questionnaire was conducted in 2015. All NH physicians in Norway (approximately 1200-1300) were invited to participate; 435 participated (response rate approximately 35%). Of the total 1664 members of the Dutch association of elderly care physicians approached, 244 participated (response rate 15%). We explored NH physicians' perceptions of organizational, educational, financial, legal, and personal prerequisites for quality EOL care. Differences between the countries were compared using χ2 test and t-test. Most respondents in both countries reported inadequate staffing, lack of skills among nursing personnel, and heavy time commitment for physicians as important barriers; this was more pronounced among Dutch respondents. Approximately 30% of the respondents in both countries reported their own lack of interest in EOL care as an important barrier. Suggested improvement strategies were routines for involvement of patients' family, pain- and symptom assessment protocols, EOL care guidelines, routines for advance care planning, and education in EOL care for physicians and nursing staff. Inadequate staffing levels, as well as lack of competence, time, and interest emerge as important barriers to quality EOL care according to Dutch and Norwegian NH physicians. Their perspectives were mostly similar, despite large educational and organizational differences. Key strategies for improving EOL care in their facilities comprise education and incorporating available palliative care tools and systems. | {
"pile_set_name": "PubMed Abstracts"
} |
Association between antennal phenotype, wing polymorphism and sex in the genus Mepraia (Reduviidae: Triatominae).
Mepraia spinolai and Mepraia gajardoi (Hemiptera, Reduviidae) are only found in the arid regions of northern Chile. Mepraia is the only genus of Triatominae with marked wing polymorphism. Females of both species are micropterous, males of M. spinolai may be micropterous, brachypterous or macropterous, while males of M. gajardoi are always brachypterous. Because of this wing polymorphism, Mepraia can be used as a model to analyze morphological adaptations related to the flying activity and evolutionary relationships in the Triatominae. The study presented here analyses the antennal phenotype of the Mepraia species and carries out a comparison with the two species of Triatoma included in the spinolai complex (Triatoma eratyrusiformis and Triatoma breyeri). The analysis of the antennal phenotype of Mepraia showed a marked intraspecific phenotypic variability related with sex and wing condition. The number and length of multiporous trichoid sensilla (TH) on the pedicel are significantly higher and longer in winged males and are strongly reduced in females. The great length of the TH sensillum is an infrequent characteristic within Triatominae. The results show that phenetic distances between sexes are greater than between the two species. Similarity between the Mepraia species and T. eratyrusiformis was found as they all show long bristles (BR) and TH and two sized basiconic receptors (BA), a pattern that have not been observed in other species of Triatominae. These characters are not present in T. breyeri. | {
"pile_set_name": "PubMed Abstracts"
} |
Speed cameras in Sweden and Victoria, Australia--a case study.
In this article, the ideas behind two different speed camera systems in Australia, Victoria, and Sweden are explored and compared. The study shows that even if the both systems technically have the same aim--to reduce speeding--the ideas of how that should be achieved differ substantially. The approach adopted in Victoria is based on the concept that speeding is a deliberate offence in which a rational individual wants to drive as fast as possible and is prepared to calculate the costs and benefits of his behaviour. Therefore, the underlying aim of the intervention is to increase the perceived cost of committing an offence whilst at the same time decrease the perceived benefits, so that the former outweigh the latter. The Swedish approach, on the other hand, appears to be based on a belief that road safety is an important priority for the road users and one of the reasons to why road users drive too fast is lack of information and social support. In order to evaluate road safety interventions and how their effects are created together with the ambition to transfer technology, there is a need for a comprehensive understanding of the systems and their modi operandi in their specific contexts. This study has shown that there are major differences between the ideas behind the two speed camera programs in Victoria, Australia and Sweden and that these ideas have an impact on the actual design of the different systems and how these are intended to create road safety effects. | {
"pile_set_name": "PubMed Abstracts"
} |
Total synthesis of antofine using the net [5+5]-cycloaddition of gamma,delta-unsaturated carbene complexes and 2-alkynylphenyl ketones as a key step.
A compound containing all of the carbons of the anticancer agent antofine was produced in a single step from the coupling of a gamma,delta-unsaturated carbene complex with a 2-alkynylphenyl ketone derivative. Subsequent conversion to antofine was effected in three steps. | {
"pile_set_name": "PubMed Abstracts"
} |
Na,K-ATPase receptor subunits alpha 1, alpha 2 and alpha 3 mRNA in dilated cardiomyopathy.
Na,K-ATPase receptor density has been shown to be down-regulated with decreasing ejection fraction in patients with chronic heart failure. It was the aim of the present study to determine whether down-regulation is detected also at the mRNA level. Six donor hearts and six explanted hearts due to dilated cardiomyopathy (ejection fraction 23 +/- 5%) were analyzed. RNA was extracted. Quantitative Na,K-ATPase receptor catalytic subunit alpha 1, alpha 2 and alpha 3 mRNA expression was determined by solution hybridization. No cross-reactivity occurred between the three probes. alpha 1 mRNA was expressed at about 5 and 10 times higher (p < 0.001) concentrations than alpha 2 and alpha 3 mRNA, respectively, and alpha 2 mRNA higher (p < 0.001) than alpha 3. There were no differences between right and left ventricles and between donor hearts and patients with dilated cardiomyopathy. In conclusion, Na,K-ATPase alpha 1 mRNA is the predominant subunit expressed in human myocardium. Depressed ejection fraction in dilated cardiomyopathy is not associated with changed mRNA subunit expression. Documented downregulation of Na,K-ATPase activity, therefore, may be associated with the structural and membrane-related beta subunit or posttranscriptional modification of the catalytic subunits. | {
"pile_set_name": "PubMed Abstracts"
} |
Systemic collateral and pulmonary artery stenosis in patients with congenital pulmonary valve atresia and ventricular septal defect.
Angiograms of 30 patients with congenital pulmonary valve atresia, ventricular septal defect, and large systemic-pulmonary collateral arteries (SPCAs) were evaluated. All had aortography, 28 had SPCA arteriography, and 26 had right ventriculography. Seventeen (65%) of 26 patients had a right ventricular infundibulum, 23 (77%) had a pulmonary artery confluence, and five of the nine patients without a right ventricular infundibulum had a confluence. Sixty-six SPCAs of aortic origin were seen; 28 (42%) had narrowing and 21 patients (70%) had one or more narrowed SPCAs. Five patients had collaterals from internal mammary, subclavian or innominate arteries. Fourteen (47%) had hilar pulmonary artery stenosis. Of these 14 patients mild peripheral stenosis was demonstrated in five. Right aortic arch was present in 15 patients (50%). Complete angiographic delineation of pulmonary vasculature is an essential procedure for preoperative detection of pulmonary and SPCA stenoses in these patients. | {
"pile_set_name": "PubMed Abstracts"
} |
Macrophage colony-stimulating factor accelerates wound healing and upregulates TGF-beta1 mRNA levels through tissue macrophages.
Macrophage colony-stimulating factor (M-CSF) is produced by many cell types involved in wound repair, yet it acts specifically on monocytes and macrophages. The monocyte-derived cell is thought to be important in wound healing, but the importance of the role of tissue macrophages in wound healing has not been well defined. Dermal ulcers were created in normal and ischemic ears of young rabbits. Either rhM-CSF (17 microg/wound) or buffer was applied to each wound. Wounds were bisected and analyzed histologically at Days 7 and 10 postwounding. The amounts of epithelial growth and granulation tissue deposition were measured in all wounds. The level of increase of TGF-beta1 mRNA level in M-CSF-treated wounds was examined using competitive RT-PCR. M-CSF increased new granulation tissue formation by 37% (N = 21, P < 0.01) and 50% (P < 0.01) after single and multiple treatments, respectively, in nonischemic wounds. TGF-beta1 mRNA levels in rhM-CSF-treated wounds increased 5.01-fold (N = 8) over vehicle-treated wounds under nonischemic conditions. In contrast, no effect could be detected in ischemic wounds treated with rhM-CSF, and these wounds only showed a 1.66-fold increase in TGF-beta1 mRNA levels when compared to ischemic wounds treated with vehicle alone. GAPDH, a housekeeping gene, showed no change. As mesenchymal cells lack receptors for M-CSF, the improved healing of wounds treated with topical rhM-CSF must reflect a generalized enhancement of activation and function of tissue macrophages, as demonstrated by upregulation of TGF-beta. The lack of effect under ischemic conditions suggests that either macrophage activity and/or response to M-CSF is adversely affected under those conditions; this may suggest the pathogenesis of impaired wound healing at the cellular level. | {
"pile_set_name": "PubMed Abstracts"
} |
M-PEIs nanogels: potential nonviral vector for systemic plasmid delivery to tumor cells.
Successfully systemic gene therapy has been hindered by vector-related limitations, including toxicity and inefficient gene delivery to tumor cells after intravenous administration. In this study, we evaluated the potential of spherical polyethylenimine nanogels (M-PEIs) as a novel vector for intravenous delivery of plasmids to tumor cells. M-PEIs provided a sustained release of plasmids up to 14 days and were also effective in protecting plasmids from enzymatic degradation in serum-conditioned media. M-PEIs showed no obvious cytotoxicity to mammalian cells in vitro as well as to liver, heart and kidney in mice after intravenous injection. Importantly, following intravenous administration of M-PEIs/plasmid complexes into human hepatocellular carcinoma xenograft-bearing mice, green fluorescence protein reporter gene expression was predominantly found in the tumor. This study indicates that M-PEIs may be a candidate for systemic delivery of plasmids into tumors. | {
"pile_set_name": "PubMed Abstracts"
} |
Methods for implanting steroid-containing cannulae into the paraventricular nucleus of neonatal rats.
Implantation of cannulae into brains of neonatal rats presents methodological difficulties. We discuss such issues as avoiding tissue injury, and describe successful techniques. Cannulae size, methods of preparation, insertion, and securing are evaluated. We present a modified cannula holder applicable to the soft neonatal brain. Application of these methods to the study of glucocorticoid receptors in the neonatal rat hypothalamus is illustrated. | {
"pile_set_name": "PubMed Abstracts"
} |
Emotional response to the ano-genital examination of suspected sexual abuse.
Concerns have arisen among professionals working with children regarding potential emotional distress as a result of the ano-genital examination for suspected child sexual abuse. The purpose of this study was to describe and compare children's anxiety immediately preceding and immediately following the medical assessment of suspected child sexual abuse, including the ano-genital exam, and to examine demographic characteristics of those children reporting clinically significant anxiety. In this descriptive study, children between the ages of 8 to 18 years of age requiring an ano-genital examination for concerns of suspected sexual abuse presenting to the Child Assessment Center of the Center for Child and Family Advocacy at Nationwide Children's Hospital were asked to participate. The Multidimensional Anxiety Scale for Children (MASC-10) was utilized in the study. The MASC-10 was completed by the child before and after the physical exam for suspected sexual abuse. Although most (86%) children gave history of sexual abuse during their forensic interview, the majority (83%) of children in this study did not report clinically significant anxiety before or after the child sexual abuse examination. Children reporting clinically significant anxiety were more likely to have a significant cognitive disability, give history of more invasive forms of sexual abuse, have a chronic medical diagnosis, have a prior mental health diagnosis, have an ano-genital exam requiring anal or genital cultures, and lack private/public medical insurance. A brief assessment of child demographics should be solicited prior to exam. Children sharing demographic characteristics listed above may benefit from interventions to decrease anxiety regardless of provider ability to detect anxiety. | {
"pile_set_name": "PubMed Abstracts"
} |
Causes and therapy of microinflammation in renal failure.
Microinflammation in renal failure has been the subject of numerous studies, but the causes of the inflammatory response in these patients are not clear. There are several potential causes and possible therapies for microinflammation, and they are discussed in this review with regard to uraemia and acidosis, heart failure and volume overload, oxidative stress and iron therapy, and bioincompatibility, especially regarding dialysis membranes. In addition, issues regarding dialysate contamination and access site infection are examined, followed by a discussion of possible drug therapy for microinflammation with angiotensin-converting enzyme inhibitors, angiotensin receptor antagonists, statins, aspirin, and antioxidants, such as vitamin E. | {
"pile_set_name": "PubMed Abstracts"
} |
How have people who have stopped or reduced their alcohol consumption incorporated this into their social rituals?
Limiting alcohol consumption is beneficial for health, but can be challenging given the role alcohol plays in the rituals of many social occasions. We examined how people who stopped or reduced their alcohol consumption incorporated this change within their social rituals. We conducted 16 semi-structured one-on-one interviews with adults aged 25-65 years, who lived in Australia and had stopped or significantly reduced their alcohol consumption in the previous year. Through thematic analysis, we identified four approaches to adapting drinking rituals: replacing alcohol with other drinks, replacing drinking with other social activities, changing the meaning of drinking rituals and replacing drinking occasions with activities that achieve different goals. These approaches varied in the extent to which they reflected a low or high change in the meanings and/or behaviours attached to the ritual. Approaches involving little change, such as using alternative drinks, were more readily accepted by participants' social companions than approaches involving more substantial changes such as replacing drinking with activities achieving different goals. Considering both the role and meaning alcohol carries in social interactions, and how else these might be achieved, may assist people to stop or reduce their drinking, without sacrificing their social lives. | {
"pile_set_name": "PubMed Abstracts"
} |
Some aspects of the epidemiology, clinical manifestations, and diagnosis of human dirofilariasis caused by Dirofilaria repens.
In recent years, zoonotic filariae Dirofilaria immitis and Dirofilaria (Nochtiella) repens are gaining popularity as incidental human parasitic pathogens. The usual hosts for these nematodes are domestic and wild carnivorous animals. The medical significance of human dirofilariasis is due to frequent misdiagnosis as malignancy and in many cases diagnosis is made after invasive surgical procedures. The aim of this study was to ascertain the geographical distribution and clinical manifestations of a relatively rare among people zoonotic disease such as dirofilariasis, whose epidemiological features depends on prevalence of the parasite among usual hosts, presence of suitable vector, and human activities favoring exposure. Data for a 39-year period were analyzed, during which, in Bulgaria, were recorded 47 cases of human dirofilariasis with various organ localizations. Morphological methods were also used for species identification of Dirofilaria (N.) repens and serological diagnostic tests for filariasis. Some epidemiological parameters such as annual incidence, prevalence for different geographic areas in Bulgaria, distribution by gender (28 females and 19 males) and age (from 19 to 77 years of age) of the diseased were identified, and aspects of the clinical manifestations, diagnosis, and treatment of the disease were discussed. Comparison was made between the number of cases in Bulgaria and those in other European countries. Although the climatic and faunal conditions in Bulgaria are favorable for disease transmission between animal reservoir hosts and humans, the diagnosis of dirofilariasis is often omitted. | {
"pile_set_name": "PubMed Abstracts"
} |
Use of pulmonary capillary wedge aspirates for the antemortem diagnosis of pulmonary microvascular tumor.
The diagnosis of pulmonary lymphangitic carcinoma usually requires fiberoptic bronchoscopy with transbronchial biopsy, percutaneous needle aspiration of the lung, and/or open lung biopsy. We performed right heart catheterization in three patients with adenocarcinoma, in whom the diagnosis of pulmonary lymphangitic carcinoma was made on the basis of cytologic examination of pulmonary capillary blood. | {
"pile_set_name": "PubMed Abstracts"
} |
Endothelin stimulates steroid secretion by frog adrenal gland in vitro: evidence for the involvement of prostaglandins and extracellular calcium in the mechanism of actin of endothelin.
Endothelin (ET-1) is a pleiotropic regulatory peptide which exerts multiple endocrine actions on the cardiovascular system. In the present study, we have investigated the possible role of ET-1 in the regulation of adrenocortical cells using perifused frog interrenal (adrenal) slices. Graded doses of ET-1 from 10(-11)-10(-9) M stimulated both corticosterone and aldosterone production in a dose-dependent manner. Repeated 20-min pulses of ET-1 (10(-9) M), given at the frequency of one pulse per 90 min, resulted in a marked reduction of the secretory response after the second pulse. Prolonged administration (3 h) of ET-1 induced a rapid increase in corticosterone and aldosterone output, followed by a gradual decline of corticosteroid secretion. Perifusion of frog adrenal tissue with ET-1 (10(-9) M) caused a significant increase in the release of prostaglandin E2 (PGE2) and 6-keto-PGF1 alpha, the stable metabolite of the prostacyclin PGI2. The enhancement of PG biosynthesis preceded by 10 min the peak of corticosteroids. When repeated pulses of ET-1 were administered, a significant diminution of the production of PGE2 and 6-keto-PGF1 alpha was observed after the second pulse. The cyclooxygenase inhibitor indomethacin (5 microM) totally suppressed the stimulatory effect of ET-1 on corticosterone and aldosterone secretion; in contrast, indomethacin did not affect ACTH-evoked corticosteroid secretion. Perifusion of adrenal slices with a calcium-free solution or addition of cobalt (4 mM) induced total inhibition of the stimulatory effect of ET-1. These results demonstrate that ET-1 is a potent stimulator of corticosterone and aldosterone secretion from frog adrenal gland in vitro. Our data show that repeated or prolonged administration of ET-1 induces a rapid desensitization phenomenon. The data also indicate that ET-1-evoked corticosteroid secretion is mediated by an increase in PG biosynthesis and requires the presence of extracellular calcium. | {
"pile_set_name": "PubMed Abstracts"
} |
Neutrophil-Kupffer-cell interaction in host defenses to systemic infections.
Most relevant textbooks characterize phagocytosis by Kupffer cells as the principal mechanism for clearing bacterial pathogens from the bloodstream and eliminating them from the liver. Here, Stephen Gregory and Edward Wing discuss recent evidence indicating that the actual mechanism is far more complicated, dependent upon the complex interaction of Kupffer cells with neutrophils that immigrate into the liver following infection. | {
"pile_set_name": "PubMed Abstracts"
} |
Photochromic Hydrazone Switches with Extremely Long Thermal Half-Lives.
A family of easily accessible light-activated hydrazone switches has been developed having thermal half-lives of up to 2700 years! Structure-property analysis shows that replacing the rotor pyridyl group of our typical hydrazone switch with a phenyl one leads to the long-lived negative photochromic compounds. The switching properties of the hydrazones in both toluene and DMSO were assessed offering insights into the kinetics and thermodynamics of the switching process. | {
"pile_set_name": "PubMed Abstracts"
} |
Trait anxiety and autonomic indicators of the processing of threatening information: a cued S1-S2 paradigm.
The aim of this study was to use autonomic parameters in a cued S1-S2 task to examine associations between the processing of threatening information and trait anxiety in normal individuals. Forty-six student volunteers were designated high- or low-anxious due to pre-defined cutoff scores on the STAI. A cued S1-S2 task was presented in which the type of warning signal (S1) was consistently related to either threatening or non-threatening pictures (S2). Ten threat and 10 non-threat pictures were randomly presented. Heart rate and electrodermal activity were recorded in the time interval between S1 and S2. Results indicated deeper heart rate decelerations on threatening trials in high-anxious as compared to low-anxious individuals. For non-threatening trials, the opposite pattern was found. Moreover, high-anxious participants exhibited higher electrodermal responses to the S1, irrespective of the trial's valence as well as stronger responses to the threatening S2. Autonomic responses can, thus, be regarded as sensitive markers of information processing differences in trait anxiety. | {
"pile_set_name": "PubMed Abstracts"
} |
[PulseNet Japan: surveillance system for the early detection of diffuse outbreak based on the molecular epidemiological method].
As the foods are stocked below freezing and widely distributed, a kind of food-borne outbreak which occurs in separate regions or in different time, so called "diffuse outbreak", has been found at the present day. Unless the outbreak is early recognized, the number of victims would increase. Some methods have been developed to analyze the relatedness of bacteria isolated from the patients of enteric infections. PFGE, pulsed-field gel electrophoresis, is one of the methods and powerful to discriminate the difference in nucleotide sequences among bacterial genomes. Availability of PFGE analysis is appreciated to examine the linkage of each incident of food-borne infections in epidemiological investigation. A PFGE network, PulseNet Japan, is now under construction among National Institute of Infectious Diseases, local Health Institutes and Ministry of Health, Labour and Welfare. | {
"pile_set_name": "PubMed Abstracts"
} |
Biocompatibility of silver nitrate and ofloxacine coated bioabsorbable SR-PLLA rods.
The purpose of this study was to evaluate the biocompatibility of silver nitrate and ofloxacine coatings of bioresorbable self-reinforced poly-L-lactic acid (SR-PLLA) rods. SR-PLLA rods coated with pure poly(caprolactone-co-L-lactide) or blended with silver nitrate (10, 5 or 2 weight-%) or ofloxacine (5 or 2 weight-%) were implanted in the dorsal muscles of 25 male rabbits. Tissue reactions caused by implantation trauma were seen 1 week after implantation. The positive control and 10 w-% silver nitrate coating showed the most marked reactions 1 month after implantation. Only sparse reactions were seen 6 months after implantation. Tissue reactions were scored semi-quantitatively. As a result of this study, we concluded that silver nitrate or ofloxacine coatings up to five w-% did not alter the good biocompatibility of SR-PLLA essentially. The method may lead to the possibility of preventing bacterial adhesion to urological stents during insertion. | {
"pile_set_name": "PubMed Abstracts"
} |
Critical illness neuromuscular syndromes.
Critical illness neuromyopathy (CINM) is the most common peripheral neuromuscular disorder encountered in the ICU. Bilateral diffuse weakness predominant in the proximal part of the limbs after improvement of the acute phase of the critical illness is highly suggestive of CINM. Although muscle and peripheral nerve often are involved in combination, muscle involvement alone increasingly is identified on electrophysiological investigation, including direct muscle stimulation. Respiratory muscles also are involved, and CINM may cause delayed weaning and prolonged MV. Besides muscle immobilization and prolonged sepsis-induced multiple organ failure, which are both strong contributors to CINM, hyperglycemia and use of corticosteroids also might have a deleterious effect on the neuromuscular system in critically ill patients. | {
"pile_set_name": "PubMed Abstracts"
} |
The Brief COPE: Factor Structure and Associations With Self- and Other-Directed Aggression Among Emerging Adults.
The Brief COPE has seen frequent use across populations despite lack of confirmatory factor-analytic examination. We further examine Brief COPE validity with respect to self- and other-directed aggression because emerging adulthood represents a distinct developmental time period in which stress, poor coping, and aggression intersect. Drawing on archival data (n = 576) from a larger investigation of college student health, this cross-sectional survey study tested (1) four competing Brief COPE factor structures, (2) Brief COPE factor associations with aggression, and (3) stress by coping interactions predicting aggression outcomes. Prominent findings included (1) poor-to-marginal confirmatory factor-analytic support for a four-factor structure; (2) positive bivariate associations of avoidant coping with elevated stress, depression, suicide, self-injury, and aggression; (3) positive bivariate associations between adaptive coping strategies with stress and aggression; and (4) an interaction where avoidant coping has a stronger association with other-directed aggression for those low in stress. The interaction findings were significant for males only and applied specifically to hostility. Findings are contextualized within future Brief COPE research as well as emerging adulthood theory. | {
"pile_set_name": "PubMed Abstracts"
} |
Platelet rap1B phosphorylation is a sensitive marker for the action of cyclic AMP- and cyclic GMP-increasing platelet inhibitors and vasodilators.
Rap1B, a ras-like protein expressed in high concentrations in human platelets, serves as a substrate for protein kinase A (PKA) and, eventually, protein kinase G (PKG). We measured rap1B phosphorylation by autoradiography of 32P-labeled proteins in platelets prelabeled with [32P]-orthophosphate. Platelets coincubated with histamine-stimulated human umbilical vein endothelial cells (EC) showed increased phosphorylation of the 50-Kd vasodilator-stimulated phosphoprotein (VASP) of 2.6 +/- 0.5-fold maximally and of rap1B of 17.5 +/- 7.1-fold maximally (mean +/- SE, n = 4). Incubation of platelets with prostacyclin (PGI2), the PGI2-analogue iloprost (ILO), the nitric oxide (NO) donors SIN-1 or sodium nitroprusside (SNP) showed greater concentration-dependent phosphorylation of rap1B than of VASP. Phosphorylation of rap1B had a slow time course and was irreversible in contrast to that of VASP, which was rapid and reversible. Phosphorylation of rap1B was dependent on an increase of platelet cyclic AMP and/or cyclic GMP. Very small concentrations of ILO (50 pM), PGI2 (1 nM), and SIN-1 (100 nM) increased rap1B phosphorylation. Rap1B phosphorylation could also be detected by Western blot after incubation of platelet-rich plasma (PRP) with ILO or SIN-1. Measurement of platelet rap1B phosphorylation is a novel tool that allows monitoring of the action of labile (PGI2, NO) and more stable (ILO, SIN-1, SNP) platelet inhibitors and vasodilators that increase intracellular cyclic AMP and cyclic GMP. Determination of rap1B phosphorylation by Western blot opens new possibilities of measuring platelet-EC interactions in clinical studies and of monitoring the action of systemically applied PGI2 analogues and nitrovasodilators in pharmacologic studies. | {
"pile_set_name": "PubMed Abstracts"
} |
Repair or Reconstruction in Acute Posterolateral Instability of the Knee: Decision Making and Surgical Technique Introduction.
Complex knee injury surgeons must frequently decide whether to repair or reconstruct an acute posterolateral corner (PLC) injury. If repair is not feasible or fails, reconstruction is often necessary. Several studies have found that reconstruction has better outcomes and lower failure rates. Careful studies of the anatomy of the corner have led to the development of "two-tailed" reconstruction techniques which are becoming widely used in the field. Repair should not be completely disregarded as there are times when it is necessary, especially when no donor allograft tissue is readily available or when aggressive postoperative rehabilitation will not be performed. Optimally, if the patient has high quality tissue available for repair, it is best to combine reconstruction with repair. The authors have developed a new PLC reconstruction technique which applies the functional anatomy that has been increasingly defined. We detail these methods here, which include the use of cortical button suspensory fixation and interference screw fixation of allografts in sockets. This allows for individual and sequential intraoperative tensioning of the grafts to obtain optimal knee stability and motion. | {
"pile_set_name": "PubMed Abstracts"
} |
Chemical properties of water-soluble porphyrins. 5. Reactions of some manganese (III) porphyrins with the superoxide and other reducing radicals.
Solution properties of three manganese porphyrins, in monomeric form, were investigated. These were the 'picket-fence-like' porphyrin Mn(III)-alpha,alpha,alpha,beta- tetra-ortho(N-methylisonicotinamidophenyl)porphyrin (Mn(III)PFP) and two 'planar unhindered' porphyrins, the Mn(III)TMPyP (tetrakis (4-N-methylpyridyl)porphyrin) and Mn(III)TAP (tetra(4-N,N,N-trimethylanilinium)porphyrin). The porphyrin properties studied were: the absorption spectra in their manganic and manganous forms; acid/base properties of the aquo complexes; the effect of potential axial ligands (up to a concentration of 0.1 mol dm-3) and their one electron reduction potentials. Knowing these properties, the reaction of the Mn(III) porphyrins with the superoxide radical and other reducing radicals were studied using the pulse radiolysis technique. The second-order reaction rate constant of O2- with the Mn(III) porphyrins, which governs the catalytic efficiency of the metalloporphyrins upon the disproportionation of the superoxide radical, was 5.1 X 10(7) to 4.0 X 10(5) dm3 mol-1 s-1, depending on the pH and the nature of the metalloporphyrin. These values are at least one order of magnitude lower than found for Fe(III)TMPyP. One electron reduction of the three Mn(III) porphyrins by eaq-, CO2-, CH2OH and (CH3)2COH had similar second-order rate constants (10(9)-10(10) dm3 mol-1 s-1). That for (CH3)2(CH2)COH was about 10(5) dm3 mol-1 s-1. Reduction in all cases produced the corresponding Mn(II) porphyrin and no intermediate was found. The oxidation reaction of the Mn(II) porphyrins by O2- was approximately two orders of magnitude faster when compared to the reduction of Mn(III) porphyrins with the same radical. Since the reactivities of O2- towards the three manganese (III) compounds follow their reduction potentials, it is suggested that these reactions are governed by an outer-sphere mechanism. This suggestion is corroborated by the finding that water molecules acting as axial ligands, in these aqueous solution systems, are not replaced by another potential ligand when the latter is in the concentration range of 100 mM or less. | {
"pile_set_name": "PubMed Abstracts"
} |
Distinctive pro-inflammatory gene signatures induced in articular chondrocytes by oncostatin M and IL-6 are regulated by Suppressor of Cytokine Signaling-3.
To describe gene expression in murine chondrocytes stimulated with IL-6 family cytokines and the impact of deleting Suppressor of Cytokine Signaling-3 (SOCS-3) in this cell type. Primary chondrocytes were isolated from wild type and SOCS-3-deficient (Socs3(Δ/Δcol2)) mice and stimulated with oncostatin M (OSM), IL-6 plus the soluble IL-6 receptor (IL-6/sIL-6R), IL-11 or leukemia inhibitory factor (LIF) for 4 h. Total RNA was extracted and gene expression was evaluated by microarray analysis. Validation of the microarray results was performed using Taqman probes on RNA derived from chondrocytes stimulated for 1, 2, 4 or 8 h. Gene ontology was characterized using DAVID (database for annotation, visualization and integrated discovery). Multiple genes, including Bcl3, Junb, Tgm1, Angptl4 and Lrg1, were upregulated in chondrocytes stimulated with each gp130 cytokine. The gene transcription profile in response to OSM stimulation was pro-inflammatory and was highly correlated to IL-6/sIL-6R, rather than IL-11 or LIF. In the absence of SOCS-3, OSM and IL-6/sIL-6R stimulation induced an interferon (IFN)-like gene signature, including expression of IL-31ra and S100a9. While each gp130 cytokine induced a transcriptional response in chondrocytes, OSM- and IL-6/sIL-6R were the most potent members of this cytokine family. SOCS-3 plays an important regulatory role in this cell type, as it does in hematopoietic cells. Our results provide new insights into a hierarchy of gp130-induced transcriptional responses in chondrocytes that is normally restrained by SOCS-3 and suggest therapeutic inhibition of OSM may have benefit over and above antagonism of IL-6 during inflammatory arthritis. | {
"pile_set_name": "PubMed Abstracts"
} |
[Doping and urologic tumors].
Several substances such as growth hormone (GH), erythropoietin (Epo), and anabolic steroids (AS) are improperly utilized to increase the performance of athletes. Evaluating the potential cancer risk associated with doping agents is difficult since these drugs are often used at very high doses and in combination with other licit or illicit drugs. The GH, via its mediator, the insulin-like growth factor 1 (IGF-1), is involved in the development and progression of cancer. Animal studies suggested that high levels of GH/IGF-1 increase progression of androgen-independent prostate cancer. Clinical data regarding prostate cancer are mostly based on epidemiological studies or indirect data such as IGF-1 high levels in patients with prostate cancer. Even if experimental studies showed a correlation between Epo and cancer, no clinical data are currently available on cancer development related to Epo as a doping agent. Androgens are involved in prostate carcinogenesis modulating genes that regulate cell proliferation, apoptosis and angiogenesis. Most information on AS is anecdotal (case reports on prostate, kidney and testicular cancers). Prospective epidemiologic studies failed to support the hypothesis that circulating androgens are positively associated with prostate cancer risk. Currently, clinical and epidemiological studies supporting association between doping and urological neoplasias are not available. Nowadays, exposure to doping agents starts more prematurely with a consequent longer exposition period; drugs are often used at very high doses and in combination with other licit or illicit drugs. Due to all these elements it is impossible to predict all the side effects, including cancer; more detailed studies are therefore necessary. | {
"pile_set_name": "PubMed Abstracts"
} |
A longitudinal study to identify constraints to dairy cattle health and production in rural smallholder communities in Northern Vietnam.
The objective of the study was to investigate constraints to dairy cattle health and production in rural smallholder communities in northern Vietnam, one of the target areas of the Vietnam government's dairy development programme. A total of 99 dairy farms (11 per commune) were recruited from 9 of 32 communes in Ba Vi District, using random two-stage cluster sampling. After the initial questionnaire interviews were conducted, farms were visited at three monthly intervals over a period of 1 year. Information on several health and production parameters relating to the study cattle was collected. Using multiple indicator modelling, it was found that Fasciola infestation, farmers who had been involved in dairying for longer (not indicative of better management skills), larger herd size, and cattle being kept in a shed were linked to reduced reproductive performances. | {
"pile_set_name": "PubMed Abstracts"
} |
Prevalence of anaerobic ammonium-oxidizing bacteria in contaminated groundwater.
Anaerobic ammonium-oxidizing (anammox) bacteria perform an important step in the global nitrogen cycle: anaerobic oxidation of ammonium and reduction of nitrite to form dinitrogen gas (N(2)). Anammox organisms appear to be widely distributed in natural and artificial environments. However, their roles in groundwater ammonium attenuation remain unclear and only limited biomarker-based data confirmed their presence prior to this study. We used complementary molecular and isotope-based methods to assess anammox diversity and activity occurring at three ammonium-contaminated groundwater sites: quantitative PCR, denaturing gradient gel electrophoresis, sequencing of 16S rRNA genes, and (15)N-tracer incubations. Here we show that anammox performing organisms were abundant bacterial community members. Although all sites were dominated by Candidatus Brocadia-like sequences, the community at one site was particularly diverse, possessing four of five known genera of anammox bacteria. Isotope data showed that anammox produced up to 18 and 36% of N(2) at these sites. By combining molecular and isotopic results we have demonstrated the diversity, abundance, and activity of these autotrophic bacteria. Our results provide strong evidence for their important biogeochemical role in attenuating groundwater ammonium contamination. | {
"pile_set_name": "PubMed Abstracts"
} |
[Mortality prognostic factors of cardiogenic shock complicating an acute myocardial infarction and treated by percutaneous coronary intervention].
To determine the in-hospital prognosis and late outcome of cardiogenic shock complicating acute myocardial infarction treated by early (< 24 hours) percutaneous coronary intervention (PCI). Retrospective monocentric study of a consecutive cohort of patients undergoing early PCI (< 24 heures) for cardiogenic shock complicating acute myocardial infarction from 1994 to 2004. The cohort included 175 patients (mean age = 65 +/- 14 years, 68% male). A successful PCI was obtained in 69% of patients. The in-hospital mortality was 43%. Independent risk factors associated with an increased mortality were: absence of TIMI three flow (P < 0.0001), absence of smoking (P < 0.009) and the need for mechanical ventilation (P < 0.002). Nor stent use or anti GP IIb/IIa infusions were predictors of a better outcome. At hospital discharge, mean left ventricular ejection fraction (LVEF) was 38 +/- 12%. Kaplan-Meier estimate of survival was 63% for in-hospital survivors (maximum follow-up = 9 years). Independent predictors of an impaired long-term outcome were: a LVEF < 0.3 (P < 0.028) and 3-vessel disease on coronary angiography (P < 0.004). In-hospital mortality of patients suffering cardiogenic shock complicating acute myocardial infarction and treated by PCI remains high despite PCI improvement. The long-term survival appears, however, to be better than that of patients with coronary artery disease and low LVEF. | {
"pile_set_name": "PubMed Abstracts"
} |
Human alkyladenine DNA glycosylase uses acid-base catalysis for selective excision of damaged purines.
Human alkyladenine DNA glycosylase (AAG) protects against alkylative and oxidative DNA damage, flipping damaged nucleotides out of double-stranded DNA and catalyzing the hydrolytic cleavage of the N-glycosidic bond to release the damaged nucleobase. The crystal structure of AAG bound to a DNA substrate reveals features of the active site that could discriminate between oxidatively damaged or alkylated purines and normal purines. A water molecule bound in the active site adjacent to the anomeric carbon of the N-glycosidic bond is suggestive of direct attack by water, with Glu125 acting as a general base. However, biochemical evidence for this proposed mechanism has been lacking. The structure also fails to explain why smaller pyrimidine nucleosides are excluded as substrates from this relatively permissive active site that catalyzes the excision of a structurally diverse group of damaged purine bases. We have used pH dependencies, site-directed mutagenesis, and a variety of substrates to investigate the catalytic mechanism of AAG. Single-turnover excision of hypoxanthine and 1,N(6)-ethenoadenine follows bell-shaped pH-rate profiles, indicating that AAG-catalyzed excision of these neutral lesions requires the action of both a general acid and a general base. In contrast, the pH-rate profile for the reaction of 7-methylguanine, a positively charged substrate, shows only a single ionization corresponding to a general base. These results suggest that AAG activates neutral lesions by protonation of the nucleobase leaving group. Glu125 must be deprotonated in the active form of the enzyme, consistent with a role as a general base that activates and positions a water nucleophile. Acid-base catalysis can account for much of the 10(8)-fold rate enhancement that is achieved by AAG in the excision of hypoxanthine. The prominent role of nucleobase protonation in catalysis by AAG provides a rationale for its specialization toward damaged purines while effectively excluding pyrimidines. | {
"pile_set_name": "PubMed Abstracts"
} |
Peripheral gene expression profile of mechanical hyperalgesia induced by repeated cold stress in SHRSP5/Dmcr rats.
Repeated cold stress (RCS) is known to transiently induce functional disorders associated with hypotension and hyperalgesia. In this study, we investigated the effects of RCS (24 and 4 °C alternately at 30-min intervals during the day and 4 °C at night for 2 days, followed by 4 °C on the next 2 consecutive nights) on the thresholds for cutaneous mechanical pain responses and on peripheral expression of "pain-related genes" in SHRSP5/Dmcr rats, which are derived from stroke-prone spontaneously hypertensive rats. To define genes peripherally regulated by RCS, we detected changes in the expression of pain-related genes in dorsal root ganglion cells by PCR-based cDNA subtraction analysis or DNA microarray analysis, and confirmed the changes by RT-PCR. We found significantly changed expression in eight pain-related genes (upregulated: Fyn, St8sia1, and Tac 1; downregulated: Ctsb, Fstl1, Itpr1, Npy, S100a10). At least some of these genes may play key roles in hyperalgesia induced by RCS. | {
"pile_set_name": "PubMed Abstracts"
} |
Xenografted human amniotic fluid-derived stem cell as a cell source in therapeutic angiogenesis.
Amniotic fluid-derived stem cells (AFSCs) are pluripotent with high renewal capacity and are not tumorigenic. We tested whether AFSCs can function as a cell source for therapeutic angiogenesis in a mouse hindlimb ischemia model. Using a defined culture medium for endothelial lineage cells (ECs), we differentiated human AFSCs into AFSC-derived ECs (AFSC-ECs) in vitro, as evidenced by expression of EC markers, and capillary-like network formation on Matrigel. We assessed the in vivo therapeutic angiogenesis efficacy of AFSC-ECs in an athymic nude mouse model of hindlimb ischemia. One day after high ligation of the external iliac artery in athymic nude mice, AFSC-ECs were intramuscularly injected into ischemic limbs. The AFSC-ECs demonstrated endothelial cell characteristics in vitro. Four weeks later, AFSC-ECs transplantation significantly increased limb salvage (85%), compared to AFSCs (56%), human umbilical vein endothelial cells (HUVECs; 25%), or medium (0%). Laser Doppler perfusion analysis revealed that the ischemic/normal limb blood perfusion ratio significantly improved in the AFSC-EC group. AFSC-EC transplantation significantly increased capillary and arteriole densities as compared to AFSCs, HUVECs, and medium. Transplanted AFSC-ECs were incorporated into vessels in the ischemic region, as confirmed by immunofluorescent staining for human smooth muscle 22α or von Willebrand factor. Matrix metalloproteinase (MMP)-3 and MMP-9 expressions were significantly higher in AFSC-ECs. MMP-9 might activate angiogenesis by regulation of vascular endothelial growth factor. Our study indicated that AFSC-EC transplantation improved limb salvage and blood perfusion by promoting neovascularization. Therefore, AFSC-ECs possess the potential for therapeutic angiogenesis. | {
"pile_set_name": "PubMed Abstracts"
} |
Characteristics of rehabilitation services in high-FIM efficiency hospitals after hip fracture.
Characteristics of rehabilitation services probably explain a large proportion of the variation in clinical outcomes following hip fracture. The aim of this study was to clarify rehabilitation characteristics of high-performance hospitals after hip fracture. This is a retrospective observational study using the Japan Rehabilitation Database for the period 2005-2015. We divided facilities into high-FIM efficiency and low-FIM efficiency hospitals by using the mean of Functional Independence Measure efficiency for each hospital. We compared rehabilitation characteristics between high- and low-FIM efficiency hospitals. We identified 1247 patients with hip fracture from 12 hospitals who were eligible for analysis after applying exclusion criteria. Using one-to-one random matching on admission Functional Independence Measure, 880 pairs of patients were included for final analysis. More patients were discharged home in the high-FIM efficiency hospitals compared with low-FIM efficiency hospitals. High-FIM efficiency hospitals had significantly shorter length of stay. Patients in high-FIM efficiency hospitals received higher amounts of daily rehabilitation, early rehabilitation, and preoperative rehabilitation. Patients in high-FIM efficiency hospitals engaged in more weekend exercise and self-exercise. Our data suggested that the amount, timing, and type of rehabilitation are essential indicators of performance in acute hip fracture. J. Med. Invest. 66 : 324-327, August, 2019. | {
"pile_set_name": "PubMed Abstracts"
} |
Fasting times in caregivers of children presenting for ambulatory surgery.
It has been the anecdotal experience in this unit that many parents and guardians of children presenting for day-case surgery also fast along with their child for prolonged periods of time. There have been several episodes of parents feeling dizzy or nauseated on leaving the anesthetic room after induction of anesthesia, and many incidents of fainting in recovery when collecting their child. Our purpose was to investigate this theme further, by auditing the fasting times of caregivers coming to the induction room over a 3-month period. This information has not been previously described in the literature. We carried out a prospective audit of current practice. Data were collected by questionnaire, which caregivers were requested to complete in the holding area, after the child was checked in for theatre. Two hundred and fifty-seven caregivers fasted for 0-6 h and 223 fasted for >6 h. One hundred and fourteen caregivers fasted for 7-12 h and 109 caregivers fasted between 13 and 19 h. A large proportion of parents choose to fast with their children. Some caregivers fast for long periods. In general, this does not cause any ill effects, although some parents missed routine medications while fasting. | {
"pile_set_name": "PubMed Abstracts"
} |
[Nursing education: integrating gender equity consciousness].
Gender sensitivity influences the way a nurse handles the nursing process and can influence both patient care and public perception of the nursing profession. Nurses unaware of the influences of gender are unable to perform holistic nursing, the practice of which centers on patient-centered care. Education is essential to promote gender consciousness. Providing scenario-based education to apply gender consciousness can help nursing students integrate gender and nursing care concepts and improve nursing care quality. In addition to raising attention to this important issue, this article makes comprehensive suggestions on how to apply gender concepts in nursing education. These suggestions include requiring instructors to consider and assess their own gender consciousness in order to enhance positive gender consciousness; reviewing teaching materials to identify and remove content tainted by sexual discrimination, and emphasizing gender education in the nursing education curriculum. | {
"pile_set_name": "PubMed Abstracts"
} |
Treatment of tobacco addiction and the cardiovascular specialist.
Tobacco smoking is the leading cause of avoidable deaths worldwide, and half of these deaths are due to cardiovascular disease (CVD). Physicians specialized in the management of CVD play a key role in ensuring that all smokers with cardiovascular disorders are offered best evidence support to help them quit smoking. This review summarizes recent findings on smoking as a risk factor for CVD, effects of smoking cessation on the prognosis of CVD patients, interactions between drug treatment for CVD and smoking, effective interventions to promote quitting in CVD patients and policy issues regarding tobacco control. Smoking cessation following an acute cardiovascular event yields a substantial reduction in morbidity and mortality. Recent declines in CVD mortality were mainly a result of risk factor modification rather than improvement of medical treatments for CVD. The latter are also less effective in smokers than in nonsmokers, and smokers are at high risk of medication nonadherence. Effective interventions to support quit attempts in smokers with CVD are available. Cardiovascular specialists should encourage policy-makers to take appropriate tobacco control action. Cardiovascular specialists are in a unique position to promote cardiovascular health at the individual as well as at a population level. | {
"pile_set_name": "PubMed Abstracts"
} |
Symposium: Normal and abnormal REM sleep regulation: REM sleep in successful, usual, and pathological aging: the Pittsburgh experience 1980-1993.
Successful psychological and physical adaptation in late life correlates with preservation of sleep quality and physiological integrity of nocturnal EEG sleep measures. Failure to adapt is associated with loss of sleep continuity, alterations in the temporal distribution of delta wave activity, and by either a relative increase in REM sleep (e.g. in mood disorders) or a decrease in REM sleep (e.g. neurodegenerative disorders). Maintenance of sleep (particularly REM sleep) into late life may not be just a correlate, but also possibly a mechanism, of successful aging and thus necessary to the long-term maintenance of vitality and engagement in life. | {
"pile_set_name": "PubMed Abstracts"
} |
Some shallow-water hydroids (Cnidaria: Hydrozoa) from the central east coast of Florida, USA.
This paper gives a systematic account of 67 species, referable to 22 families and 40 genera, identified in a small collection of hydroids from the central Atlantic coast of Florida between Melbourne and Palm Beach. The fauna mostly comprises an assemblage of tropical western Atlantic species ranging northwards along the southeastern coast of the United States. One new species, Lafoea intorta, is described. Applying Reversal of Precedence provisions in zoological nomenclature, the widely-used generic name Halopteris Allman, 1877 is designated as valid and as a nomen protectum, while its virtually unused senior synonym Halicornaria Hincks, 1865 (not Halicornaria Allman, 1874) is reduced to a nomen oblitum. The genus Pasya Stechow, 1922 is resurrected for the hydroid generally known as Dynamena quadridentata (Ellis & Solander, 1786). Laomedea tottoni Leloup, 1935 is shown to be a junior objective synonym of Clytia fragilis Congdon, 1907, which in turn is a junior subjective synonym of Clytia linearis (Thornely, 1900). Obelia oxydentata Stechow, 1914 is recognized as distinct from O. bidentata Clark, 1875. Hincksella brevitheca Galea, 2009, first described from Cuba, is reported for only the second time; records of the species are added here from Grand Cayman Island and the Caribbean coast of Panama as well as from the Atlantic coast of Florida. Also reported for the second time is Antennella incerta Galea, 2010, previ-ously known only from Guadeloupe in the Caribbean Sea. The true Halopteris diaphana (Heller, 1868), known from the Mediterranean Sea and from Brazil, is reported for the first time from the western North Atlantic. Earlier records of the species in the region are based on misidentifications of H. alternata (Nutting, 1900). Male gonothecae of Halecium calderi Galea, 2010 are reported and illustrated for the first time. | {
"pile_set_name": "PubMed Abstracts"
} |
[An analysis of combined desensitizing acupoints therapy in 419 cases of allergic rhinitis accompanying asthma].
To explore the effective therapy in treating allergic rhinitis accompanying asthma. A combined desensitizing therapy in treating 419 cases of allergic rhinitis accompanying asthma caused by allergens has been carried out using acupoint of the head and the upper back with the extract of positive allergen(s). After three treatment courses, the extract of allergens was taken again to make intradermal injection. Diameter of redness and swelling on the skin was significantly reduced in comparison with that before the treatment (P < 0.01). Lymphocyte transformation difference of 3H-TdR incorporation rate between a combined desensitizing acupoints group and A or B control groups was significant (P < 0.01). Difference of acidophil cell direct count, IgA, IgG, E-rosette formative rate of this group in comparison with A or B control groups was significant (P < 0.05). Four hundred and nineteen cases were followed up for 3 years, 68.73% of the patients were markedly curative effect; 29.12% turned better. Comparison of the difference of this group with the other two control groups was significant (P < 0.01). This article showed that the method is promising and worthwhile for popularizing in treatment of allergic rhinitis accompanying allergic asthma. | {
"pile_set_name": "PubMed Abstracts"
} |
Open bite treatment using clear aligners.
A 35-year-old female patient with dentoalveolar open bite of 4 mm, molar Class I malocclusion, centered midlines, moderate crowding, and labial inclination of the lower incisor was treated with clear aligners to reduce protrusion and close the anterior open bite. The result showed that clear aligners were an effective method with which to correct this malocclusion. The treatment was complete after 18 months. The patient was satisfied with her new appearance and function. | {
"pile_set_name": "PubMed Abstracts"
} |
STRA13 interacts with STAT3 and modulates transcription of STAT3-dependent targets.
STRA13 is a pVHL-dependent bHLH transcription factor up-regulated on the mRNA level in multiple cancer cell lines and implicated recently in the regulation of immune cell homeostasis and autoimmunity. In searching for STRA13-interacting proteins with oncogenic potential by the yeast two-hybrid screening, we identified STAT3 beta as a STRA13-binding partner. We showed that STRA13 binds predominantly to phosphorylated (active) STAT3 alpha and beta isoforms via its HLH and C-terminal regions. We also found that STRA13 was able to activate transcription from STAT-dependent cis-elements. Expression of endogenous STRA13 was shown to be cytokine-inducible, consistent with STRA13 involvement in STAT-dependent transcription regulation. We demonstrated that the STAT3-regulated promoter of the pro-apoptotic Fas gene was activated upon STRA13 over-expression and that co-expression of STRA13 with STAT3 beta or STAT3 alpha modulated the transcriptional outcome. Forced expression of STRA13 induced apoptosis, in agreement with the STRA13 activation effect on the Fas promoter. Simultaneous expression of STRA13 and STAT3 beta resulted in alleviation of the STRA13 pro-apoptotic effect. Thus, for the first time, we identify STRA13 as a STAT3 partner and provide a consistent line of evidence for STRA13 involvement into regulation of apoptosis via the STAT pathways. | {
"pile_set_name": "PubMed Abstracts"
} |
[Treatment of neuromyelitis optica].
Neuromyelitis optica (NMO) or Devic's disease is an inflammatory neurologic disease characterized by severe optic neuritis and transverse myelitis. Other features of NMO include female preponderance, higher onset age, severe functional disability, longitudinally extensive spinal cord lesions (longer than 3 vertebral segments), and oligoclonal IgG bands negativity. Brain lesions are not uncommon in NMO. The relation between NMO and multiple sclerosis (MS) has long been a matter of controversy, but since the discovery of anti-aquaporin 4 (AQP4) antibody (NMO-IgG), an NMO-specific autoantibody, the clinical, MRI, and laboratory features that distinguish NMO from MS have been clarified. Anti-AQP4 antibody binds to the extracellular domain of AQP4, which is highly expressed in endfeet of astrocytes. Recent neuropathological studies, analysis of CSF-GFAP levels during relapse and experimental studies strongly suggest that NMO is an anti-AQP4 antibody-mediated astrocytopathic disease and that T cell-mediated CNS inflammation is necessary to develop NMO. Also, IL-6 is remarkably elevated in the CSF and appears to regulate plasmablasts to produce anti-AQP4 antibody. Therefore, from the therapeutic point of view, depletion of anti-AQP4 antibody, suppression of T cell response to trigger relapse and anti-IL-6 therapy seem to be pivotal. High-dose intravenous methylprednisolone is the first-line therapy for acute exacerbations of NMO. But plasma exchange should be started soon if corticosteroid is not efficacious. If untreated, AQP4 antibody-positive patients are highly likely to experience relapses within a year. Thus, immunosuppressive therapy (corticosteroids, immunosuppressants, rituximab) should be initiated without delay. Preliminary results suggest that eculizumab, an anti-C5 monoclonal antibody, can also prevent relapse in NMO, Meanwhile, interferon-beta, a first-line disease modifying drug of MS, is not effective in NMO. Symptomatic therapy for pain, paresthesia, spasticity, dysuria and constipation which commonly occur in the chronic stage of NMO is also important to improve patients' quality of life. | {
"pile_set_name": "PubMed Abstracts"
} |
Caffeine consumption and anxiety and depressive symptomatology among medical students.
Caffeine is one of the most widely consumed psychoactive substances in the world and is ingested in a variety of favorites, such as coffee, tea, cola and so on. Although it has been suggested that high dose caffeine users have more anxiety and depressive symptoms than low users, this relationship is not clear in Japan, where caffeine consumption is considered to be less than in Western countries. A questionnaire survey was conducted among medical students and 291 out of 423 initial subjects completed it. Among males, caffeine consumption was significantly and positively correlated with anxiety symptoms, when alcohol use and smoking habit were adjusted. However, there was no relationship between caffeine consumption and depressive symptoms. Among females, although there was no association between caffeine consumption and anxiety symptoms, high dose caffeine users showed less depressive symptoms than moderate and low users, when alcohol use was adjusted. It is suggested that caffeine use is one of the important factors, in researching psychological health among the general population. We need further epidemiological studies to determine whether there is a causal relationship between caffeine and psychological ill health or not. | {
"pile_set_name": "PubMed Abstracts"
} |
New adjuvants: EU regulatory developments.
This paper discusses EU regulatory texts that are relevant for the introduction of new adjuvants in human vaccines and discusses the EU requirements at the developmental level, during the manufacturing process and at the final product stage. The emphasis is on regulatory expectations regarding safety at preclinical and clinical stages. The article highlights regulatory concerns and existing bottlenecks that have led to a slow approval process for new adjuvants. | {
"pile_set_name": "PubMed Abstracts"
} |
Infectious agents and age-related neurodegenerative disorders.
chlamdAs with other organ systems, the vulnerability of the nervous system to infectious agents increases with aging. Several different infectious agents can cause neurodegenerative conditions, with prominent examples being human immunodeficiency virus (HIV-1) dementia and prion disorders. Such infections of the central nervous system (CNS) typically have a relatively long incubation period and a chronic progressive course, and are therefore increasing in frequency as more people live longer. Infectious agents may enter the central nervous system in infected migratory macrophages, by transcytosis across blood-brain barrier cells or by intraneuronal transfer from peripheral nerves. Synapses and lipid rafts are important sites at which infectious agents may enter neurons and/or exert their cytotoxic effects. Recent findings suggest the possibility that infectious agents may increase the risk of common age-related neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and stroke. While scenarios can be envisioned whereby viruses such as Chlamydia pneumoniae, herpes simplex and influenza promote damage to neurons during aging, there is no conclusive evidence for a major role of these pathogens in neurodegenerative disorders. In the case of stroke, blood vessels may be adversely affected by bacteria or viruses resulting in atherosclerosis. | {
"pile_set_name": "PubMed Abstracts"
} |
[Venous ulcer on the hand due to a treatment-related arteriovenous fistula].
An arteriovenous fistula of the arm for hemodialysis needs to last long and provide easy access for puncture. A 50 year-old woman, with type 2 diabetes complicated by chronic renal failure, presented with an ulcer on the dorsum of the right hand that had developed over the past year. Humeral artery to basilica vein, side-to-side, arteriovenous fistula in the right arm was created in 1996. In 1999, she received a renal transplant. In 2002, she developed a deep ulcer on the dorsum of the right hand that progressed over one year, without improvement good local treatment. Doppler echography and a fistulography revealed proximal stenosis of the basilica vein, and a less restricted distal stenosis before the shunt. A venous ulcer on the dorsum of the hand due excessive venous pressure in the draining area. The complications of arteriovenous fistulas can be severe. Arterial stenosis is frequent and is the consequence of intimal hypertrophy. Chronic ischemia symptoms can be observed, but the hemodynamic loss is usually asymptomatic. When clinical signs are noisy emergency surgery is required. Venous stenosis is responsible for ischemia through venous overload, leading to edema of the arm, and rarely to venous-ulcer type trophic disorders as seen in this patient. Screening for stenosis on the vascular vein network must be systematic before creating an arteriovenous fistula. | {
"pile_set_name": "PubMed Abstracts"
} |
Involvement of oxidative stress, NF-IL-6, and RANTES expression in dengue-2-virus-infected human liver cells.
The liver has been suspected to be one of the major targets of dengue virus infection. Here, we detected increasing secretion of the chemokine RANTES (regulated upon activation, normal T cell expressed and secreted), which functions to recruit the immune cells, in dengue-virus-infected liver cells and patients. Three luciferase reporter genes with various deletions at the 5'-end of the RANTES promoter were constructed to explore the RANTES activation mechanism in human liver cells. The reporter gene was optimally activated by dengue-2 virus when the RANTES promoter contains the region from the transcription starting site (+1) to the nucleotide at the -181 position. NF-IL-6 and an undefined factor forming DNA-protein complexes in the RANTES promoter E and A/B regions in the infected cells were demonstrated by electrophoretic mobility shift assay. Further analysis showed that oxidative stress was an upstream inducer of NF-IL-6 and RANTES signaling in dengue-virus-infected liver cells. This finding was demonstrated by three antioxidants (N-acetyl-l-cysteine, nitro-l-arginine methyl ester, and pyrrolidine dithiocarbamate) used to suppress the activation. In contrast, the DNA binding activity of the undefined factor was not affected by the antioxidant treatment, indicating the existence of an oxidant-independent pathway. We hypothesize that dengue virus infection of the liver cells may trigger both an oxidant-dependent and an oxidant-independent pathway to up-regulate RANTES mRNA expression through activating NF-IL-6 and an undefined factor, respectively. In conclusion, the present study suggests a new direction for the study of liver pathogenesis involving RANTES in host immune responses during dengue virus infection. | {
"pile_set_name": "PubMed Abstracts"
} |
[Ultrasound in the diagnostics of fatty liver in obesity].
Chronic diffuse liver diseases produce a characteristic ultrasound image called bright liver. On the basis of liver attenuation, two major appearances can be observed: low and high attenuation types. It is proved that high attenuation is associated with fatty liver and subcutaneous fat thickness correlates with attenuation. Cut-off value of attenuation and subcutaneous fat thickness was searched for differentiation of the two attenuation types and that of the normal livers. 441 patients (proved by histology) were examined by ultrasound. 132 normal livers, 176 low and 133 high attenuation type bright livers were found. Cut-off level of attenuation, determined by frequency distribution analysis was defined as 1.1 dB/cm/MHz, between fatty liver and low attenuation type bright liver and normal liver. Cut-off value for subcutaneous fat thickness could not be determined. It is concluded, that above the cut-off point of attenuation, the diagnosis of fatty liver can be established without liver biopsy. Subcutaneous fat thickness values give additive confirmative data. | {
"pile_set_name": "PubMed Abstracts"
} |
Short- and long-term influence of the levonorgestrel-releasing intrauterine system (Mirena®) on vaginal microbiota and Candida.
Recurrent vulvovaginal infections are a frequent complaint in young women in need of contraception. However, the influence of the contraceptive method on the course of the disease is not well known. To investigate the influence of the levonorgestrel-releasing intrauterine-system (LNG-IUS) on the vaginal microflora. Short-term (3 months) and long-term (1 to 5 years) changes of vaginal microbiota were compared with pre-insertion values in 252 women presenting for LNG-IUS insertion. Detailed microscopy on vaginal fluid was used to define lactobacillary grades (LBGs), bacterial vaginosis (BV), aerobic vaginitis (AV) and the presence of Candida. Cultures for enteric aerobic bacteria and Candida were used to back up the microscopy findings. Fisher's test was used to compare vaginal microbiome changes pre- and post-insertion. Compared to the pre-insertion period, we found a temporary worsening in LBGs and increased rates of BV and AV after 3 months of LNG-IUS. After 1 and 5 years, however, these changes were reversed, with a complete restoration to pre-insertion levels. Candida increased significantly after long-term carriage of LNG-IUS compared to the period before insertion [OR 2.0 (CL951.1-3.5), P=0.017]. Short-term use of LNG-IUS temporarily decreases lactobacillary dominance, and increases LBG, AV and BV, but after 1 to 5 years these characteristics return to pre-insertion levels, reducing the risk of complications to baseline levels. Candida colonization, on the other hand, is twice as high after 1 to 5 years of LNG-IUS use, making it less indicated for long-term use in patients with or at risk for recurrent vulvovaginal candidosis. | {
"pile_set_name": "PubMed Abstracts"
} |
Light- and electron microscopic characteristics of the vegetative centers in the guinea pig sacral spinal cord intermediate zone.
A dense AChE-negative and NA fluorescent network was visualized by light microscopy in the sacral spinal cord intermediate zone of grown-up guinea pigs of both sexes. This network connects in horizontal and vertical direction the preganglionic vegetative nuclei (n. intermediolateralis pars principalis (ILp), n. intermediolateralis pars funicularis (ILf), n. intercalatus spinalis (IC), n. intercalatus pars paraependimalis (ICpe), (Petras and Cummings 1972) along 2--4 segments of the spinal cord. Electron microscopy demonstrated dense core ves icles (40--100 nm) in the cytoplasm of the ILp cells. The surface of the ILp neurons is covered with synaptic boutons which have clear and dense core vesicles (40--100 nm). The bundles of fibres connecting the vegetative nuclei are built of parallel myelinated fibres and myelinfree axons and dendrites. On their course the axons form varicosites. In the latter and in the synaptic enlargements there are clear and dense core (40--100 nm) vesicles. The probable origin of the vegetative fibres of guinea pig sacral spinal cord is discussed. | {
"pile_set_name": "PubMed Abstracts"
} |
Association of Mean Platelet Volume with Acute Ischemic Cerebrovascular Accident Among Patients with Type 2 Diabetes Mellitus: A Hospital-Based Study.
To study the association of MPV (mean platelet volume) and acute ischemic stroke in patients of type 2 diabetes mellitus (DM). This was a 1-year cross-sectional hospital-based study involving 79 patients presented with acute ischemic stroke. Among them, 25 were diabetic and 54 were nondiabetic. Demographic data and history of the patients were recorded. Investigations such as haemoglobin estimation, platelet count, MPV, HbA1c, imaging studies were conducted and evaluated for acute ischemic brain stroke. All the patients underwent neurological examination according to National Institute of Health Stroke Scale (NIHSS) at the time of admission and MPV was noted. Outcome of stroke was assessed during discharge by modified Rankin morbidity (MRM) score. SPSS 20 was used to analyse the data. Among 79 them, 25 patients (31.6%) had history of diabetes which formed the diabetic subset and the remaining 54 (68.35%) were considered in non-diabetic subset. MPV in patients with DM was significantly high (10.16 ± 0.89 fL) compared to nondiabetic patients (8.25 ± 0.91 fL; p<0.001). The mean NIHSS scores were significantly high in patients with diabetes compared to nondiabetic patients (20.38±3.19 vs. 17.76±3.74; p=0.006). Also, the mean MRM scores were significantly high in diabetics than that of nondiabetics (4.12 ± 0.66 vs. 3.00 ± 0.61; p<0.001). History of stroke was present in 12% of patients with DM compared to 1.85% of the non-diabetic patients (p=0.091). Acute ischemic stroke in diabetic patients is significantly associated with raised MPV level, which is likely to be severe with high morbidity and mortality. Hence, MPV is an easily available blood parameter, which defines platelet reactivity and proves to be a good predictor of severity and outcome of stroke in diabetics. Also, higher percentile of patients showed history of recurrent stroke in diabetics as compared to non-diabetics in whom the MPV was considerably raised compared to other diabetic stroke cases. | {
"pile_set_name": "PubMed Abstracts"
} |
First and Second Step Characteristics of Amputee and Able-Bodied Sprinters.
In sprint events, the first 2 steps are used to accelerate the center of mass horizontally and vertically. Amputee athletes cannot actively generate energy with their running-specific prosthesis. It is likely that sprint acceleration mechanics, including step asymmetry, are altered compared with able-bodied athletes. To investigate spatiotemporal and kinetic variables of amputee compared with able-bodied sprinters. Kinematic and kinetic data of the first and second stance were collected from 15 able-bodied and 7 amputee sprinters (2 unilateral transfemoral, 4 unilateral transtibial, and 1 bilateral transtibial) with a motion-capture system (250 Hz) and 2 force plates (1000 Hz). In addition, bilateral asymmetry was quantified and compared between groups. Compared with able-bodied athletes, amputee athletes demonstrated significantly lower performance values for 5- and 10-m times. Step length, step velocity, and step frequency were decreased and contact times increased. Peak horizontal force and relative change of horizontal velocity were decreased in both stances. Peak vertical force and relative change of vertical velocity were lower for the amputee than the able-bodied group during the first stance but significantly higher during the second stance. During the first stance, able-bodied and amputee sprinters displayed a similar orientation of the ground-reaction-force vector, which became more vertically orientated in the amputee group during second stance. Amputee sprinters showed significantly greater asymmetry magnitudes for vertical force kinetics compared with able-bodietd athletes. A running-specific prosthesis does not replicate the function of the biological limb well in the early acceleration phase. | {
"pile_set_name": "PubMed Abstracts"
} |
Halomonas beimenensis sp. nov., isolated from an abandoned saltern.
A Gram-staining negative, motile, non-spore-forming, short rod-shaped (0.8-1.5 × 1.5-2.0 µm), halophilic bacterium, designated strain NTU-107(T), was isolated from brine samples collected from the abandoned Beimen saltern in southern Taiwan. The novel strain grew with 0-15% (w/v) NaCl (optimum between 5% and 10%), at 15-55 °C (optimum 40 °C) and at pH 5.5-9.5 (optimum pH 7.5). The major cellular fatty acids were C(18:1)ω7c, C(16:0) and C(19:0 )cyclo ω8c, the genomic DNA G+C content was 66.5 mol%, and the predominant ubiquinone was Q-9. The major polar lipids included phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. In a phylogenetic analysis based on 16S rRNA gene sequences, strain NTU-107(T) clustered with members of the genus Halomonas. In hybridization experiments, however, the levels of DNA-DNA relatedness between strain NTU-107(T) and the type strains of its closest phylogenetic neighbours (Halomonas koreensis, H. organivorans and H. ventosae) were all found to be less than 40 %. Based on the phenotypic, chemotaxonomic and genetic data, strain NTU-107(T) represents a novel species within the genus Halomonas, for which the name Halomonas beimenensis sp. nov. is proposed. The type strain is NTU-107(T) ( = BCRC 17999(T) = KCTC 22876(T) = JCM 16084(T)). | {
"pile_set_name": "PubMed Abstracts"
} |
Regulation of bone lysis in inflammatory diseases.
Focal bone erosion is a major pathological feature of several common inflammatory diseases. Over the past decade there have been major advances in our understanding of the factors that regulate osteoclast formation and activity. It is now apparent that receptor activator for NFkappaB (RANK), its ligand RANKL (also known as TRANCE, osteoclast differentiation factor and osteoprotegerin (OPG) ligand) and the RANKL inhibitor OPG, are the major factors regulating osteoclast formation. These molecules influence normal bone physiology and now there is growing evidence that RANK-RANKL interactions also regulate osteoclast formation in disease. This paper reviews recent findings showing expression of RANK, RANKL and OPG in inflammatory diseases including rheumatoid arthritis, periodontal disease and peri-implant loosening. It is emerging that OPG and RANKL are key molecules regulating bone loss in disease and therapeutic intervention that targets these molecules may be helpful in treating a wide range of diseases. | {
"pile_set_name": "PubMed Abstracts"
} |
[Choice of antibiotic therapy for acute streptococcus A sore throat: new bacteriologic data].
The choice of antibiotic therapy for sore throat of bacterial origin must be directed against the beta-haemolytic streptococcus A, or more rarely C and G. Recent bacteriological data confirm the raised and constant antibacterial activity in vitro of penicillins V and G, with minimal inhibitory concentrations (CMI) as low as 0.01 mg/ml. Until now, there have been no resistant or reduced sensitivity strains reported. Those strains reported as "tolerant" to penicillin are not correlated with therapeutic checks. As for strains of "intermediate sensitivity" to penicillin, these should be attributed to effects of the diffusion techniques. In contrast, in France now, 8% of strains of streptococcus A are resistant to macrolides and 60% to tetracyclines. Finally, new data show that the different selective powers of beta-lactamines, especially cephalosporins, introduce risks of modification of the oro-pharingeal ecology, linked in part with transfer of genetic material between commensal streptococci of reduced sensitivity to beta-lactamines to sensitive pneumococci. All these data emphasize the importance of an antibiotic therapy that is directed to streptococcus A, with a strong and constant bactericidal activity, without risk of selection or appearance of strains of resistant streptococcus A, and that will not disturb the long term bacterial ecology of the oro-pharynx. Now, in 1994 phenoxymethylpenicillin, Oracilline, penicillin V has the place of reference in the treatment of bacterial acute sore throat. | {
"pile_set_name": "PubMed Abstracts"
} |
Purification, crystallization and preliminary crystallographic studies of an integral membrane protein, cytochrome bo3 ubiquinol oxidase from Escherichia coli.
Cytochrome bo(3) ubiquinol oxidase has been successfully purified for crystallization. Single crystals of this integral membrane protein diffract X-rays to 3.5 A resolution and belong to the orthorhombic space group C222(1). From the diffraction data, the unit-cell parameters were determined to be a = 91.3, b = 370.3, c = 232.4 A. The crystals have a solvent content of 59% and contain two molecules per asymmetric unit. A search model generated from the structures of cytochrome c oxidase from Paracoccus denitrificans and the extrinsic domain of cytochrome bo(3) ubiquinol oxidase from Escherichia coli was used for molecular-replacement studies, resulting in a solution with sensible molecular packing. | {
"pile_set_name": "PubMed Abstracts"
} |
Intercalation of 3-phenyl-1-proponal into OTS SAMs on silica nanoasperities to create self-repairing interfaces for MEMS lubrication.
Self-assembled monolayers (SAMs) have been widely studied as potential lubricants for microelectromechanical system (MEMS) devices. However, these single-layer films have nominally been found to be insufficient for mitigating wear in sliding contacts because of their rapid breakdown under the high pressures found within the nanoasperity junctions at such interfaces. As such, there is a critical need to explore approaches beyond simple, single-component SAMs toward films that introduce additional lubricant molecules into the system. Because alcohol vapors have previously been shown to reduce wear in MEMS devices, here we have investigated a mixed monolayer consisting of an octadecyltrichlorosilane (OTS) SAM infused with 3-phenyl-1-propanol (3P1P), assembled on silica nanoparticle films. A combination of atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), and FTIR spectroscopy was employed to investigate the structural and frictional properties of the mixed monolayers and to evaluate surface wear as a function of time. The nanoparticle film/AFM tip junction provides a ready mimic for the asperity-asperity contacts found in MEMS devices. Here it was found that for a mixed monolayer of OTS with ca. 15% 3P1P, the surfaces showed dramatically reduced friction and no wear under the same load conditions as surfaces with an OTS SAM alone. Moreover, the multicomponent film also displayed no increase in friction and exhibited no wear even after 14 h of shearing contact in an AFM at loads that would break down the OTS layer. The ability of the OTS SAM to trap short-chain alcohols, such as 3P1P, and to release them under load suggests a simple MEMS lubrication scheme that could be readily integrated into MEMS device architectures. | {
"pile_set_name": "PubMed Abstracts"
} |
Gambogic acid enhances the radiosensitivity of human esophageal cancer cells by inducing reactive oxygen species via targeting Akt/mTOR pathway.
Radiotherapy is a widespread treatment in human solid tumors. However, therapy resistance and poor prognosis are still problems. Gambogic acid (GA), extracted from the dried yellow resin of gamboges, has an anticancer effect against various types of cancer cells. To explore the radiosensitivity of GA on esophageal cancer cell line TE13, cell viability was tested by Cell Counting Kit-8 (CCK-8) assay, colony formation assay was used to assess the effects of GA on the radiosensitivity of TE13, and flow cytometry was performed to meter the percentage of apoptosis. The protein levels of microtubule-associated protein 1 light chain 3 (LC3), caspase3, caspase8, casepase9, pAkt, and p-mammalian target of rapamycin (p-mTOR) were tested using Western blot. The distribution of LC3 was detected by immunofluorescence. Additionally, we also examined reactive oxygen species (ROS) expression by laser scanning confocal microscope (LSCM). The cells were transfected with adenovial vector to monitor the autophagy through the expression of green fluorescent protein (GFP-red fluroscent protein (RFP)-LC3. The rates of apoptotic cells in combined-treated TE13 increased significantly compared with the control groups in accordance with the results of Western blot. The clonogenic survival assay showed that GA enhances radiosensitivity with a sensitizing enhancement ratio (SER) of 1.217 and 1.436 at different concentrations. The LC3-II protein level increased in the combined group indicating the increase of autophagy incidence, and the results of GFP-RFP-LC3 experiment showed that GA may block the process of autophagic flux in TE13 cells. Moreover, we successfully demonstrated that ROS is involved in the induction of autophagy. ROS-mediated autophagy depends on the inhibition of the Akt/mTOR pathway. Taken together, GA induced radiosensitivity involves autophagy and apoptosis which are regulated by ROS hypergeneration and Akt/mTOR inhibition. | {
"pile_set_name": "PubMed Abstracts"
} |
The 'medical body' as philosophy's arena.
Medicine, as Byron Good argues, reconstitutes the human body of our daily experience as a "medical body," unfamiliar outside medicine. This reconstitution can be seen in two ways: (i) as a salutary reminder of the extent to which the reality even of the human body is constructed; and (ii) as an arena for what Stephen Toulmin distinguishes as the "intersection" of natural science and history, in which many of philosophy's traditional (and traditionally abstract) questions are given concrete and urgent form. This paper begins by examining a number of dualities between the medical body and the body familiar in daily experience. Toulmin's epistemological analysis of clinical medicine as combining both universal and existential knowledge is then considered. Their expression, in terms of attention, respectively, to natural science and to personal history, is explored through the epistemological contrasts between the medical body and the familiar body, noting the traditional philosophical questions which they in turn illustrate. | {
"pile_set_name": "PubMed Abstracts"
} |
Countervailing social network influences on problem behaviors among homeless youth.
The impact of countervailing social network influences (i.e., pro-social, anti-social or HIV risk peers) on problem behaviors (i.e., HIV drug risk, HIV sex risk or anti-social behaviors) among 696 homeless youth was assessed using structural equation modeling. Results revealed that older youth were less likely to report having pro-social peers and were more likely to have HIV risk and anti-social peers. A longer time homeless predicted fewer pro-social peers, more anti-social peers, and more HIV risk peers. Heterosexual youth reported fewer HIV risk peers and more pro-social peers. Youth recruited at agencies were more likely to report pro-social peers. Having pro-social peers predicted less HIV sex risk behavior and less anti-social behavior. Having HIV risk peers predicted all problem behavior outcomes. Anti-social peers predicted more anti-social behavior. Once the association between anti-social and HIV risk peers was accounted for independently, having anti-social peers did not independently predict sex or drug risk behaviors. | {
"pile_set_name": "PubMed Abstracts"
} |
Feedback control of glomerular filtration rate in isolated, blood-perfused dog kidneys.
Micropuncture studies were done in isolated, blood-perfused dog kidneys to investigate the intrarenal nature of tubuloglomerular feedback regulation of nephron filtration rate. Collections were made at early proximal tubular sites during alterations in flow through the loop of Henle to elicit the feedback response. Renal blood flow in the 10 isolated kidneys averaged 4 ml/ min-g kidney after an initial vasoconstriction. Filtration rate was 0.52 +/- 0.12 ml/min-g kidney for the period 90-120 min, but progressively fell after 120 min, as did fractional sodium reabsorption and PAH extraction. The feedback regulation of nephron filtration rate was demonstrated during the first 3 hrs of perfusion even with subnormal renal function. The feedback response expressed as the percent reduction of early proximal flow rate when loop of Henle flow was elevated from 0 to 45 nl/min was 41.3 +/- 4.5 (for the first 90 min), 35.3 +/- 7.5 (90-120 min), 24.3 +/- 6.8 (120-150 min), and 26.6 +/- 7.7% (150-180 min). After 180 min, the feedback response was no longer demonstrated. These results show that feedback-induced changes in nephron filtration rate are achieved in the absence of nervous system influences. | {
"pile_set_name": "PubMed Abstracts"
} |
Secondary hyperparathyroidism in diabetic and nondiabetic patients on long-term continuous ambulatory peritoneal dialysis (CAPD).
Serum values of calcium, phosphate, alkaline phosphatases and parathyroid hormone (PTH) are reported for 24 diabetic and 26 nondiabetic patients treated with continuous ambulatory peritoneal dialysis (CAPD) for a total of 779 months, without the use of vitamin D or calcium supplements. Radiographic data are reported for 25 patients followed on CAPD for at least 12 months. Serum calcium was well maintained and control of hyperphosphataemia acceptable, but phosphate-binding therapy had to be continued in the majority of patients. Diabetic patients had lower serum phosphate levels and higher serum calcium than nondiabetic patients during the first year of CAPD. In nondiabetic patients the institution of CAPD was followed by a fall in PTH, possibly largely reflecting transperitoneal PTH elimination. No patient achieved normalization of serum PTH on CAPD. Although no symptomatic bone disease was observed, radiographic evidence of progressive hyperparathyroid bone disease developed in 3 of the 25 examined patients, all nondiabetic. In summary, long-term CAPD with a dialysate calcium concentration of 1.75 mmol/l seems to be compatible with normocalcaemia and a steady-state situation with regard to secondary hyperparathyroidism in the majority of patients. Despite transperitoneal elimination, serum PTH remains elevated, and definite progression of hyperparathyroidism is observed in some patients, however, probably making a case for vitamin D therapy and/or intraperitoneal or peroral calcium supplementation in these patients. | {
"pile_set_name": "PubMed Abstracts"
} |
[A case of infantile virilizing adrenocortical tumor].
The patient was a 16-month-old girl, born by mature natural delivery and weighing 3,320 g. Hirsutism was noted on birth. Development of pubic hair and hypertrophy of the labia minora were noted after 8 months. At the time of admission, the height was 80 cm and body weight 14.5 kg. Systemic obesity, facial acne, systemic hirsutism, low pitched voice and hypertrophied clitoris were observed. Androstenedione, dehydroepiandrosterone-sulfate and cortisol showed high levels in the blood, and the urinary 17-KS was obviously high, along with an increase in urinary 17-OHCS. The subject did not respond to either the dexamethasone inhibition test or ACTH load test. The abdominal CT revealed a tumor in the front upper position of the left kidney, and adrenal scintigraphy disclosed an obvious accumulation image in the adrenal gland on the left side. Based on the diagnosis of a left adrenal tumor, left adrenalectomy was performed. The tumor measured 5.0 x 4.5 x 3.7 cm, and weighed 57 g. Histopathologically it was diagnosed as adrenocortical adenoma. The infantile virilizing adrenocortical tumor is reported together with some discussion of the literature. | {
"pile_set_name": "PubMed Abstracts"
} |
Hydroxyproline-rich protein in the capsule of a strain of Staphylococcus aureus.
A protein fraction containing a high amount of hydroxyproline was found in the capsule of the Smith diffuse strain (encapsulated) when compared with that of dialysate medium. This content varied depending upon temperature, oxygen supply, sodium chloride, and carbohydrates. The hydroxyproline content of the single proteinaceous fraction, obtained by Sephadex G-200 column chromatography, was one fourth of the total amino acid composition. | {
"pile_set_name": "PubMed Abstracts"
} |
Delay in diagnosis of breast cancer. A professional liability risk.
This article notes that liability claims of failure to diagnose breast cancer are increasing in number and severity, at least in part because women understand that early diagnosis improves survival. Legal cases are presented that illustrate particular liability risks, and risk management recommendations are made. | {
"pile_set_name": "PubMed Abstracts"
} |
Single crystalline magnetite nanotubes.
We descried a method to synthesize single crystalline Fe3O4 nanotubes by wet-etching the MgO inner cores of MgO/Fe3O4 core-shell nanowires. Homogeneous Fe3O4 nanotubes with controllable length, diameter, and wall thickness have been obtained. Resistivity of the Fe3O4 nanotubes was estimated to be approximately 4 x 10-2 Omega cm at room temperature. Magnetoresistance of approximately 1% was observed at T = 77 K when a magnetic field of B = 0.7 T was applied. The synthetic strategy presented here may be extended to a variety of materials such as YBCO, PZT, and LCMO which should provide ideal candidates for fundamental studies of superconductivity, piezoelectricity, and ferromagnetism in nanoscale structures. | {
"pile_set_name": "PubMed Abstracts"
} |
Raman spectroscopy of breast tissues.
Breast cancer is one of the leading female cancers. The major drawback of the gold standard of screening, mammography, is the high rate of false reports, aside from the risk from repeated exposure to harmful ionizing radiations. Histopathology, the gold standard of diagnosis, is time consuming and often prone to subjective interpretations. Molecular level diagnosis 'omics' is becoming increasingly popular; among these is metabolomics, diagnosis based on 'metabolic fingerprinting'. In the present article we review a Raman spectroscopic approach to metabolic fingerprinting in breast cancer detection. This review opens with a brief background on anatomical and etiological aspects of breast cancers. We present an overview of conventional detection approaches in breast cancer screening and diagnosis methods, followed by a concise note on the basics of optical spectroscopy and its applications in the screening/diagnosis of breast malignancy. We present the recent developments in Raman spectroscopic diagnosis of breast cancers and also share our experience in Raman spectroscopic classification of normal, benign and malignant breast tissues. Perspectives and current status of Raman spectroscopic screening/diagnosis of breast cancers are also discussed. | {
"pile_set_name": "PubMed Abstracts"
} |
New perspectives in the diagnosis of Echinococcus disease.
Echinococcosis, an endemic disease on the Asian continent, is caused by the tapeworm Tenia Echinococcus, which produces cysts in the liver and other organs. I reviewed 157 patients with hydatid disease of the liver. The hydatid cysts were single in 125 patients and predominantly in the right lobe, but multiple in 31 patients, localized in both lobes or in the lung, spleen, pancreas, heart, or peritoneum. In 14 patients, early complications were manifested by rupture of the cyst into the biliary tract, the lung, or the peritoneum. Infection of the cysts was rare. Late postsurgical complications, noted in 10, were the development of an abscess or cirrhosis. I evaluated the importance of computed tomography (CT) in the diagnosis of hydatidosis of the liver and other visceral organs: It made a correct and accurate diagnosis in 96% of 157 patients. But, in ruptured or infected cysts, CT scans could not distinguish between a hydatid cyst and an abscess. Surgery is still the treatment of choice in hydatid disease. It is absolutely indicated in complicated cases, and is easy and curative in uncomplicated ones. I have used Mebendazole in 18 patients for 2 years without significant benefit, except in two patients with disseminated hydatidosis. Mebendazole stabilized the disease. | {
"pile_set_name": "PubMed Abstracts"
} |
Regulation of D-amino acid oxidase expression in the yeast Rhodotorula gracilis.
Rhodotorula gracilis is a oleaginous yeast which utilizes D-amino acids as a source of carbon and/or nitrogen. D-amino acid oxidase (DAAO), which converts D-amino acids in the corresponding alpha-keto acids and ammonia, is the first enzyme involved in the catabolism of D-amino acids. DAAO activity is induced by the presence of D-alanine, but the presence of the L-isomer prevents induction by inhibiting the transport of D-alanine into cells. To understand how DAAO expression is regulated, R. gracilis cells were grown on media containing different nitrogen and/or carbon sources. As a general rule, the level of DAAO mRNA reached a maximum after 15 h growth and preceded by approximately 6 h the maximum level of DAAO activity. The inducer D-alanine acts by increasing the rate of DAAO mRNA transcription: the increase in DAAO expression is due essentially to de novo synthesis. The presence of a supplemental carbon source (e.g. succinate or glucose) does not repress DAAO expression. Ammonium sulphate appears to have a negative effect on DAAO mRNA translation and on the expression of DAAO activity: DAAO is only partially active when the yeast is grown in the presence of D-alanine and ammonium sulphate. The best expression of DAAO activity was obtained by growing the cells for 12 h at 30 degrees C in the presence of glucose and D-alanine using cells pre-cultured for 10 h on glucose and L-alanine (0.99 U/mg protein, corresponding to approximately 1.0% total proteins in the crude extract). Under these growth conditions a six-fold increase in DAAO production was achieved. | {
"pile_set_name": "PubMed Abstracts"
} |
Identification, clinical-pathological characteristics and treatment outcomes of patients with metastatic breast cancer and somatic human epidermal growth factor receptor 2 (ERBB2) mutations.
The human epidermal growth factor receptor 2 (ERBB2) may harbour somatic mutations that drive breast tumorigenesis. Here, we study prevalence, tumour characteristics and disease outcome of ERBB2 mutations in a large unselected cohort of metastatic breast cancer (mBC) patients. We retrospectively included all mBC patients with sufficient primary breast tumour, diagnosed between 2000 and 2015 (n = 775). Genomic DNA was subjected to a targeted-resequencing assay to identify hotspot mutations in exon 8, 17, 19, 20, and 21 of ERBB2. We studied demographics, tumour characteristics, median distant disease-free survival (DDFS), using a time-to-event analysis and time to progression (TTP) and overall survival (OS) upon metastasis, using Kaplan-Meier and log-rank statistics to assess differences between ERBB2-mutation statuses. ERBB2 mutations were observed in 1.8% of the samples (13/721). Patient and tumour characteristics were independent of ERBB2 mutations. Luminal ERBB2-mutated (ERBB2mut+) cases (n = 5) had a shorter DDFS than ERBB2mut- cases (median DDFS 0.8 vs. > 4.0 years, p = 0.02). ER-positive ERBB2mut+ patients who received an aromatase inhibitor (AI) as first-line treatment (stage IV disease) had a worse TTP vs. ERBB2mut- patients (n = 3 vs. 156; median TTP 103 vs. 311 days, p = 0.04). OS for all subtypes was lower for ERBB2mut+ vs. ERBB2mut- cases (n = 11 vs. 669; median OS 1.1 vs. 2.3 years, p = 0.46). ERBB2mut+ are rare in patients in whom mBC developed and no evidence was found for an association with specific types of BC or patient characteristics, although outcomes of ERBB2mut+ carriers might be worse. The latter, however, needs to be validated in larger populations. | {
"pile_set_name": "PubMed Abstracts"
} |
Histamine H3 Receptor Ligands in the Group of (Homo)piperazine Derivatives.
Since its discovery in 1983, followed by gene cloning in 1999, the histamine H3 receptor served as an outstanding target for drug discovery. The wide spectrum of possible therapeutic implications makes H3R's one of the most researched areas in the vast GPCR ligands field - started from imidazole containing ligands, through various successful imidazole replacements, with recent introduction of Wakix® to pharmaceutical market. One such replacement is piperazine moiety, a significant versatile scaffold in rational drug design for most of the GPCR ligands. Therefore, herein, we review ligands built on piperazine, as well as its seven membered analogue azepine, that target H3R's and their potential therapeutical applications, in order to elucidate the current state of the art in this vast field. Due to a high level of structural divergence among compounds described herein, we decided to divide them into groups, where the key division element was the position of nitrogen basicity decreasing moieties in (homo)piperazine ring. Paying attention to a number of published structures and their overall high biological activity, one can realize that the (homo)piperazine scaffold bids a versatile template also for histamine H3 receptor ligands. With two possible substitution sites and therefore a number of possible structural combinations, piperazine derivatives stand as one of the largest group of high importance among H3R ligands. | {
"pile_set_name": "PubMed Abstracts"
} |
A Synaptic Basis for GLP-1 Action in the Brain.
Unraveling the brain control of metabolism may generate opportunities to discover novel precision medicines for obesity and diabetes. In this issue of Neuron, Liu et al. (2017) identify a novel glucagon-like peptide (GLP)-1 receptor-dependent signaling process that exerts anorexigenic action via the regulation of AMPA receptor subunit composition in the hypothalamus. | {
"pile_set_name": "PubMed Abstracts"
} |
High expression of DNA repair pathways is associated with metastasis in melanoma patients.
We have identified a gene-profile signature for human primary malignant melanoma associated with metastasis to distant sites and poor prognosis. We analyse the differential gene expression by looking at whole biological pathways rather than individual genes. Among the most significant pathways associated with progression to metastasis, we found the DNA replication (P=10(-14)) and the DNA repair pathways (P=10(-16)). We concentrated our analysis on DNA repair and found that 48 genes of this category, among a list of 234 genes, are associated with metastatic progression. These genes belong essentially to the pathways allowing recovery of stalled replication forks due to spontaneous blockage or induced DNA lesions. Because almost all these differentially expressed repair genes were overexpressed in primary tumors with bad prognosis, we speculate that primary melanoma cells that will metastasize try to replicate in a fast and error-free mode. In contrast to the progression from melanocytes to primary melanoma, genetic stability appears to be necessary for a melanoma cell to give rise to distant metastasis. This overexpression of repair genes explains nicely the extraordinary resistance of metastatic melanoma to chemo- and radio-therapy. Our results may open a new avenue for the discovery of drugs active on human metastatic melanoma. | {
"pile_set_name": "PubMed Abstracts"
} |
[Inhibition of the expression of prostate specific antigen by curcumin].
To study the effect of curcumin on the expression of prostate specific antigen (PSA). AXSYM system-chemical luciferase method was used to examine the content of PSA in prostate cancer cell lines, LNCap after treated with different doses of curcumin. pGL3-PSA luciferase expression vector, containing 640 bp DNA of PSA gene 5' promoter region was constructed and transfected into LNCap cell with lipofectin. Through detecting the activity of luciferase, the effect of curcumin on the promoter of PSA was studied. Western blotting was used to detect expression of androgen receptor (AR) in LNCap cell with different concentrations of curcumin. The expression of PSA was inhibited and activity of luciferase was reduced by curcumin. There was also significant difference in AR expression as shown by Western blotting experiment after treatment of different doses of curcumin. Through inhibiting AR expression, curcumin reduced the function of PSA promoter and inhibited PSA protein expression. | {
"pile_set_name": "PubMed Abstracts"
} |
Conjugated linoleic acid increased C-reactive protein in human subjects.
We previously showed that conjugated linoleic acid (CLA) increases 15-keto-dihydro-prostaglandin F2alpha, a marker for cyclooxygenase-mediated lipid peroxidation and thus an indicator of cyclooxygenase-mediated inflammation. The aim of the present study was to investigate the effects of CLA on other indicators of inflammation in human subjects, including C-reactive protein, TNF-alpha, TNF-alpha receptors 1 and 2, and vascular cell adhesion molecule-1. In a double-blind, placebo-controlled study, fifty-three human subjects were supplemented with a mixture (4.2 g/d) of the isomers cis-9,trans-11 CLA and trans-10,cis-12 CLA or control oil for 3 months. CLA supplementation increased levels of C-reactive protein (P=0.003) compared with the control group. However, no changes in TNF-alpha, TNF-alpha receptors 1 and 2, and vascular cell adhesion molecule-1 were detected. | {
"pile_set_name": "PubMed Abstracts"
} |
c-Met expression is regulated by Mitf in the melanocyte lineage.
Hepatocyte growth factor (HGF)/c-Met signaling is thought to be a key pathway in both melanocyte development and melanoma metastasis. Here, HGF stimulation of melanocytes was seen to up-regulate c-Met expression. In an effort to decipher the mechanism by which HGF up-regulates its receptor, we found that c-Met is a direct transcriptional target of Mitf. This was confirmed with chromatin immunoprecipitation experiments of the human c-Met promoter, as well as by the ability of adenovirally expressed Mitf to modulate endogenous c-Met protein levels in melanocytes. Disruption of Mitf blocked HGF-dependent increases in endogenous c-Met message and protein levels, indicating that HGF regulates its own receptor levels via Mitf. Finally, dominant-negative inhibition of Mitf resulted in profound resistance of melanocytes and melanoma cells to HGF-dependent matrix invasion, suggesting a physiologic role for this pathway in melanocytic development and melanoma. | {
"pile_set_name": "PubMed Abstracts"
} |
Inhibition of steroidogenic response to corticotropin in mouse adrenal tumor cells (Y-1) by the ionophore A23187. Role of protein biosynthesis.
Addition of the ionophore A23187 to Y-1 mouse adrenal tumor cells in monolayer culture inhibits steroidogenesis and the steroidogenic response to corticotropin (50% inhibition at 1 . 10(-7)M). Inhibition is rapid in onset and is not overcome by addition of external Ca2+. The ionophore also inhibits stimulation of steroid synthesis by cyclic AMP. A23187 inhibits incorporation of the amino acid lysine into protein by Y-1 cells and the dose dependence of this inhibition closely resembles that of the inhibition of the steroidogenic response to corticotropin. Addition of A23187 to a subcellular system for protein synthesis prepared from Y-1 cells, inhibits incorporation of the amino acid phenylalanine into protein and this effect is not overcome by high concentrations of Ca2+. The inhibitory effect of A23187 on the response to corticotropin, like that response itself, takes place at some part of steroid synthesis after entry of cholesterol into the cells and before the side-chain cleavage of cholesterol. These studies confirm the importance of protein synthesis in the response to corticotropin and demonstrate that the effect of protein synthesized under the influence of corticotropin is exerted at some point in the events which bring substrate (cholesterol) to the mitochondrial side-chain cleavage enzyme system. It is also shown that A23187 inhibits protein synthesis, and hence the response to corticotropin, by a mechanism which is independent of the concentration of available Ca2+. | {
"pile_set_name": "PubMed Abstracts"
} |
[Progress in streptothricin antibiotics - A review].
Streptothricins are a group of the earliest discovered antibiotics with broad antimicrobial spectrum, and have been used for crop protection. We reviewed the studies on streptothricin resistance, biosynthesis of the three components (streptolidine, carbamoylated D-glucosamine and poly β-lysine chain) and chemical synthesis of streptothricins. The important aspects for future streptothricin researches were also discussed. | {
"pile_set_name": "PubMed Abstracts"
} |
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