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Santana Wu posted an update 1 day, 8 hours ago
With growing evidence of inhalation of small infectious particles as an important mode of transmission for SARS-CoV-2, workplace risk assessments should focus on eliminating or minimizing such exposures by applying the hierarchy of controls. We adapt a control banding model for aerosol-transmissible infectious disease pandemic planning to encourage the use of source and pathway controls before receptor controls (personal protective equipment). Built on the recognition that aerosol-transmissible organisms are likely to exhibit a dose-response function, such that higher exposures result from longer contact times or higher air concentrations, this control banding model offers a systematic method for identifying a set of source and pathway controls that could eliminate or reduce the need for receptor controls. We describe several examples for workers at high risk of exposure in essential or return to work categories. The goal of using control banding for such workers is to develop effective infection and disease prevention programs and conserve personal protective equipment.Acquiring a foreign language is challenging for many adults. Yet certain individuals choose to acquire sometimes dozens of languages and often just for fun. Is there something special about the minds and brains of such polyglots? Using robust individual-level markers of language activity, measured with fMRI, we compared native language processing in polyglots versus matched controls. Polyglots (n = 17, including nine “hyper-polyglots” with proficiency in 10-55 languages) used fewer neural resources to process language Their activations were smaller in both magnitude and extent. click here This difference was spatially and functionally selective The groups were similar in their activation of two other brain networks-the multiple demand network and the default mode network. We hypothesize that the activation reduction in the language network is experientially driven, such that the acquisition and use of multiple languages makes language processing generally more efficient. However, genetic and longitudinal studies will be critical to distinguish this hypothesis from the one whereby polyglots’ brains already differ at birth or early in development. This initial characterization of polyglots’ language network opens the door to future investigations of the cognitive and neural architecture of individuals who gain mastery of multiple languages, including changes in this architecture with linguistic experiences.Pathogenic muscle-specific tyrosine kinase (MuSK)-specific IgG4 autoantibodies in autoimmune myasthenia gravis (MG) are functionally monovalent as a result of Fab-arm exchange. The development of these unique autoantibodies is not well understood. We examined MG patient-derived monoclonal autoantibodies (mAbs), their corresponding germline-encoded unmutated common ancestors (UCAs), and monovalent antigen-binding fragments (Fabs) to investigate how affinity maturation contributes to binding and immunopathology. Mature mAbs, UCA mAbs, and mature monovalent Fabs bound to MuSK and demonstrated pathogenic capacity. However, monovalent UCA Fabs bound to MuSK but did not have measurable pathogenic capacity. Affinity of the UCA Fabs for MuSK was 100-fold lower than the subnanomolar affinity of the mature Fabs. Crystal structures of two Fabs revealed how mutations acquired during affinity maturation may contribute to increased MuSK-binding affinity. These findings indicate that the autoantigen drives autoimmunity in MuSK MG through the accumulation of somatic mutations such that monovalent IgG4 Fab-arm-exchanged autoantibodies reach a high-affinity threshold required for pathogenic capacity.Type I interferons (IFN-I) are a major antiviral defense and are critical for the activation of the adaptive immune system. However, early viral clearance by IFN-I could limit antigen availability, which could in turn impinge upon the priming of the adaptive immune system. In this study, we hypothesized that transient IFN-I blockade could increase antigen presentation after acute viral infection. To test this hypothesis, we infected mice with viruses coadministered with a single dose of IFN-I receptor-blocking antibody to induce a short-term blockade of the IFN-I pathway. This resulted in a transient “spike” in antigen levels, followed by rapid antigen clearance. Interestingly, short-term IFN-I blockade after coronavirus, flavivirus, rhabdovirus, or arenavirus infection induced a long-lasting enhancement of immunological memory that conferred improved protection upon subsequent reinfections. Short-term IFN-I blockade also improved the efficacy of viral vaccines. These findings demonstrate a novel mechanism by which IFN-I regulate immunological memory and provide insights for rational vaccine design.
Sleep disturbances may contribute to physical function impairment among older adults.
To examine the associations between sleep quality and duration and impaired physical function among older adults.
Cross-sectional study involving 392 non-institutionalized adults aged ≥65 years, who were recruited from primary health care centres in Spain. Sleep quality and duration were assessed with the Pittsburgh Sleep Quality Index (PSQI). The FRAIL scale was used to identify physical frailty, the short physical performance battery to assess lower extremity functional impairment (LEFI) and grip strength was measured using a hand-held dynamometer to assess muscle weakness. Statistical analyses were performed with logistic regression models adjusted for potential confounders.
Participants with poor sleep quality (PSQI global score ≥10) were more likely to have functional limitations; the odds ratio (95% confidence interval) was 2.90 (1.10-7.64) for physical frailty, 2.73 (1.34-5.58) for LEFI and 2.32 (1.14-4.75) for muscle weakness. Sleep quality components associated with frailty were sleep disturbances, use of sleeping medication and daytime dysfunction. The only quality component associated with LEFI was poor sleep efficiency, while subjective poor sleep quality and daytime dysfunction were linked to muscle weakness. No associations were observed between night-time sleep duration and physical function indicators.
Poor self-reported sleep quality, but not sleep duration, was associated with an increased frequency of physical frailty, LEFI and muscle weakness. Interventions to improve sleep quality could contribute to healthy ageing.
Poor self-reported sleep quality, but not sleep duration, was associated with an increased frequency of physical frailty, LEFI and muscle weakness. Interventions to improve sleep quality could contribute to healthy ageing.