991 resultados para Kirk, Bernard
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We report the case of a congenital myasthenic syndrome due to a mutation in AGRN, the gene encoding agrin, an extracellular matrix molecule released by the nerve and critical for formation of the neuromuscular junction. Gene analysis identified a homozygous missense mutation, c.5125G>C, leading to the p.Gly1709Arg variant. The muscle-biopsy specimen showed a major disorganization of the neuromuscular junction, including changes in the nerve-terminal cytoskeleton and fragmentation of the synaptic gutters. Experiments performed in nonmuscle cells or in cultured C2C12 myotubes and using recombinant mini-agrin for the mutated and the wild-type forms showed that the mutated form did not impair the activation of MuSK or change the total number of induced acetylcholine receptor aggregates. A solid-phase assay using the dystrophin glycoprotein complex showed that the mutation did not affect the binding of agrin to alpha-dystroglycan. Injection of wild-type or mutated agrin into rat soleus muscle induced the formation of nonsynaptic acetylcholine receptor clusters, but the mutant protein specifically destabilized the endogenous neuromuscular junctions. Importantly, the changes observed in rat muscle injected with mutant agrin recapitulated the pre- and post-synaptic modifications observed in the patient. These results indicate that the mutation does not interfere with the ability of agrin to induce postsynaptic structures but that it dramatically perturbs the maintenance of the neuromuscular junction.
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A passive sampling device, called Monitor of NICotine (MoNIC), was constructed and evaluated by the laboratory of the Institute for Work and Health to determine nicotine in Environmental Tobacco Smoke (ETS). To support a large campaign on the subject of passive smoking, the CIPRET Valais gracefully distributed more than 1500 MoNIC badges to the Swiss population in order to measure ETS. Non-stimulated saliva was also collected to determine nicotine/cotinine levels of participating volunteers. The inhaled Cigarette Equivalents (CE) by non-smokers was calculated for non-smokers, based on a reference of 0.2 mg of nicotine per cigarette. Using the detected CE on the badge for non-smokers, and comparing it to the nicotine/cotinine levels in saliva, we could confirm the use of the CE concept for estimating exposure to ETS
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ABSTRACT: Iron deficiency without anemia (IDWA) is related to adverse symptoms that can be relieved by supplementation. Since a blood donation can induce such an iron deficiency, we investigated the clinical impact of an iron treatment after blood donation. METHODS: One week after donation, we randomly assigned 154 female donors with IDWA aged <50 years to a 4-week oral treatment of ferrous sulfate vs. placebo. The main outcome was the change in the level of fatigue before and after the intervention. Also evaluated were aerobic capacity, mood disorder, quality of life, compliance and adverse events. Biological markers were hemoglobin and ferritin. RESULTS: Treatment effect from baseline to 4 weeks for hemoglobin and ferritin were 5.2 g/L (p < 0.01) and 14.8 ng/mL (p < 0.01) respectively. No significant clinical effect was observed for fatigue (-0.15 points, 95% confidence interval -0.9 to 0.6, p = 0.697) or for other outcomes. Compliance and interruption for side effects was similar in both groups. Additionally, blood donation did not induce overt symptoms of fatigue in spite of the significant biological changes it produces. CONCLUSIONS: These data are valuable as they enable us to conclude that donors with IDWA after a blood donation would not clinically benefit from iron supplementation. Trial registration: NCT00689793.
Resumo:
Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.
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INTRODUCTION: Systematic literature reviews provide best evidence, but are underused by clinicians. Thus, integrating Cochrane reviews into continuing medical education (CME) is challenging. We designed a pilot CME program where summaries of Cochrane reviews (Courriels Cochrane) were disseminated by e-mail. Program participants automatically received CME credit for each Courriel Cochrane they rated. The feasibility of this program is reported (delivery, participation, and participant evaluation). METHOD: We recruited French-speaking physicians through the Canadian Medical Association. Program delivery and participation were documented. Participants rated the informational value of Courriels Cochrane using the Information Assessment Method (IAM), which documented their reflective learning (relevance, cognitive impact, use for a patient, expected health benefits). IAM responses were aggregated and analyzed. RESULTS: The program was delivered as planned. Thirty Courriels Cochrane were delivered to 985 physicians, and 127 (12.9%) completed at least one IAM questionnaire. Out of 1109 Courriels Cochrane ratings, 973 (87.7%) conta-ined 1 or more types of positive cognitive impact, while 835 (75.3%) were clinically relevant. Participants reported the use of information for a patient and expected health benefits in 595 (53.7%) and 569 (51.3%) ratings, respectively. DISCUSSION: Program delivery required partnering with 5 organizations. Participants valued Courriels Cochrane. IAM ratings documented their reflective learning. The aggregation of IAM ratings documented 3 levels of CME outcomes: participation, learning, and performance. This evaluation study demonstrates the feasibility of the Courriels Cochrane as an approach to further disseminate Cochrane systematic literature reviews to clinicians and document self-reported knowledge translation associated with Cochrane reviews.
Resumo:
Enregistrement : (France) [Studio Bernard Roux, Paris], 28-01-1925 - 28-07-1926
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Enregistrement : (France) [Studio Bernard Roux, Paris], -.]-[s.d