2,133 research outputs found

    Innate immunity during SARS-CoV-2: evasion strategies and activation trigger hypoxia and vascular damage

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    Innate immune sensing of viral molecular patterns is essential for development of antiviral responses. Like many viruses, SARS-CoV-2 has evolved strategies to circumvent innate immune detection, including low cytosine–phosphate–guanosine (CpG) levels in the genome, glycosylation to shield essential elements including the receptor-binding domain, RNA shielding and generation of viral proteins that actively impede anti-viral interferon responses. Together these strategies allow widespread infection and increased viral load. Despite the efforts of immune subversion, SARS-CoV-2 infection activates innate immune pathways inducing a robust type I/III interferon response, production of proinflammatory cytokines and recruitment of neutrophils and myeloid cells. This may induce hyperinflammation or, alternatively, effectively recruit adaptive immune responses that help clear the infection and prevent reinfection. The dysregulation of the renin–angiotensin system due to down-regulation of angiotensin-converting enzyme 2, the receptor for SARS-CoV-2, together with the activation of type I/III interferon response, and inflammasome response converge to promote free radical production and oxidative stress. This exacerbates tissue damage in the respiratory system, but also leads to widespread activation of coagulation pathways leading to thrombosis. Here, we review the current knowledge of the role of the innate immune response following SARS-CoV-2 infection, much of which is based on the knowledge from SARS-CoV and other coronaviruses. Understanding how the virus subverts the initial immune response and how an aberrant innate immune response contributes to the respiratory and vascular damage in COVID-19 may help to explain factors that contribute to the variety of clinical manifestations and outcome of SARS-CoV-2 infection

    Antipsychotic dose escalation as a trigger for Neuroleptic Malignant Syndrome (NMS): literature review and case series report

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    Background: “Neuroleptic malignant syndrome” (NMS) is a potentially fatal idiosyncratic reaction to any medication which affects the central dopaminergic system. Between 0.5% and 1% of patients exposed to antipsychotics develop the condition. Mortality rates may be as high as 55% and many risk factors have been reported. Although rapid escalation of antipsychotic dose is thought to be an important risk factor, to date it has not been the focus of a published case series or scientifically defined. <p/>Aims: To identify cases of NMS and review risk factors for its development with a particular focus on rapid dose escalation in the 30 days prior to onset. <p/>Methodology: A review of the literature on rapid dose escalation was undertaken and a pragmatic definition of “rapid dose escalation” was made. NMS cases were defined using DSM-IV criteria and systematically identified within a secondary care mental health service. A ratio of titration rate was calculated for each NMS patient and “rapid escalators” and “non rapid escalators” were compared. <p/>Results: 13 cases of NMS were identified. A progressive mean dose increase 15 days prior to the confirmed episode of NMS was observed (241.7mg/day during days 1-15 to 346.9mg/day during days 16-30) and the mean ratio of dose escalation for NMS patients was 1.4. Rapid dose escalation was seen in 5/13 cases and non rapid escalators had markedly higher daily cumulative antipsychotic dose compared to rapid escalators. <p/>Conclusions: Rapid dose escalation occurred in less than half of this case series (n=5, 38.5%), although there is currently no consensus on the precise definition of rapid dose escalation. Cumulative antipsychotic dose – alongside other known risk factors - may also be important in the development of NMS

    Vocal Communications and the Maintenance of Population Specific Songs in a Contact Zone

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    Bird song has been hypothesized to play a role in several important aspects of the biology of songbirds, including the generation of taxonomic diversity by speciation; however, the role that song plays in speciation within this group may be dependent upon the ability of populations to maintain population specific songs or calls in the face of gene flow and external cultural influences. Here, in an exploratory study, we construct a spatially explicit model of population movement to examine the consequences of secondary contact of populations singing distinct songs. We concentrate on two broad questions: 1) will population specific songs be maintained in a contact zone or will they be replaced by shared song, and 2) what spatial patterns in the distribution of songs may result from contact? We examine the effects of multiple factors including song-based mating preferences and movement probabilities, oblique versus paternal learning of song, and both cultural and genetic mutations. We find a variety of conditions under which population specific songs can be maintained, particularly when females have preferences for their population specific songs, and we document many distinct patterns of song distribution within the contact zone, including clines, banding, and mosaics

    Applying refinement to the use of mice and rats in rheumatoid arthritis research

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    Rheumatoid arthritis (RA) is a painful, chronic disorder and there is currently an unmet need for effective therapies that will benefit a wide range of patients. The research and development process for therapies and treatments currently involves in vivo studies, which have the potential to cause discomfort, pain or distress. This Working Group report focuses on identifying causes of suffering within commonly used mouse and rat ‘models’ of RA, describing practical refinements to help reduce suffering and improve welfare without compromising the scientific objectives. The report also discusses other, relevant topics including identifying and minimising sources of variation within in vivo RA studies, the potential to provide pain relief including analgesia, welfare assessment, humane endpoints, reporting standards and the potential to replace animals in RA research

    Optical Magnetometry

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    Some of the most sensitive methods of measuring magnetic fields utilize interactions of resonant light with atomic vapor. Recent developments in this vibrant field are improving magnetometers in many traditional areas such as measurement of geomagnetic anomalies and magnetic fields in space, and are opening the door to new ones, including, dynamical measurements of bio-magnetic fields, detection of nuclear magnetic resonance (NMR), magnetic-resonance imaging (MRI), inertial-rotation sensing, magnetic microscopy with cold atoms, and tests of fundamental symmetries of Nature.Comment: 11 pages; 4 figures; submitted to Nature Physic

    Psychological determinants of whole-body endurance performance

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    Background: No literature reviews have systematically identified and evaluated research on the psychological determinants of endurance performance, and sport psychology performance-enhancement guidelines for endurance sports are not founded on a systematic appraisal of endurance-specific research. Objective: A systematic literature review was conducted to identify practical psychological interventions that improve endurance performance and to identify additional psychological factors that affect endurance performance. Additional objectives were to evaluate the research practices of included studies, to suggest theoretical and applied implications, and to guide future research. Methods: Electronic databases, forward-citation searches, and manual searches of reference lists were used to locate relevant studies. Peer-reviewed studies were included when they chose an experimental or quasi-experimental research design, a psychological manipulation, endurance performance as the dependent variable, and athletes or physically-active, healthy adults as participants. Results: Consistent support was found for using imagery, self-talk, and goal setting to improve endurance performance, but it is unclear whether learning multiple psychological skills is more beneficial than learning one psychological skill. The results also demonstrated that mental fatigue undermines endurance performance, and verbal encouragement and head-to-head competition can have a beneficial effect. Interventions that influenced perception of effort consistently affected endurance performance. Conclusions: Psychological skills training could benefit an endurance athlete. Researchers are encouraged to compare different practical psychological interventions, to examine the effects of these interventions for athletes in competition, and to include a placebo control condition or an alternative control treatment. Researchers are also encouraged to explore additional psychological factors that could have a negative effect on endurance performance. Future research should include psychological mediating variables and moderating variables. Implications for theoretical explanations of endurance performance and evidence-based practice are described

    An Improved Technique for Chromosomal Analysis of Human ES and iPS Cells

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    Prolonged in vitro culture of human embryonic stem (hES) cells can result in chromosomal abnormalities believed to confer a selective advantage. This potential occurrence has crucial implications for the appropriate use of hES cells for research and therapeutic purposes. In view of this, time-point karyotypic evaluation to assess genetic stability is recommended as a necessary control test to be carried out during extensive ‘passaging’. Standard techniques currently used for the cytogenetic assessment of ES cells include G-banding and/or Fluorescence in situ Hybridization (FISH)-based protocols for karyotype analysis, including M-FISH and SKY. Critical for both banding and FISH techniques are the number and quality of metaphase spreads available for analysis at the microscope. Protocols for chromosome preparation from hES and human induced pluripotent stem (hiPS) cells published so far appear to differ considerably from one laboratory to another. Here we present an optimized technique, in which both the number and the quality of chromosome metaphase spreads were substantially improved when compared to current standard techniques for chromosome preparations. We believe our protocol represents a significant advancement in this line of work, and has the required attributes of simplicity and consistency to be widely accepted as a reference method for high quality, fast chromosomal analysis of human ES and iPS cells

    Current challenges in software solutions for mass spectrometry-based quantitative proteomics

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    This work was in part supported by the PRIME-XS project, grant agreement number 262067, funded by the European Union seventh Framework Programme; The Netherlands Proteomics Centre, embedded in The Netherlands Genomics Initiative; The Netherlands Bioinformatics Centre; and the Centre for Biomedical Genetics (to S.C., B.B. and A.J.R.H); by NIH grants NCRR RR001614 and RR019934 (to the UCSF Mass Spectrometry Facility, director: A.L. Burlingame, P.B.); and by grants from the MRC, CR-UK, BBSRC and Barts and the London Charity (to P.C.

    Pediatricians' perspectives on the impact of MRSA in primary care: a qualitative study

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    <p>Abstract</p> <p>Background</p> <p>The incidence of skin and soft-tissue infections (SSTIs) has rapidly increased among children in primary care settings since the emergence of community-associated methicillin-resistant <it>Staphylococcus aureus </it>(CA-MRSA). Recent treatment recommendations emphasize CA-MRSA as the primary cause, performing incision and drainage (I&D) as the primary therapy, and not prescribing antibiotics for uncomplicated cases. It is unknown how this epidemic has impacted primary care pediatricians in terms of their practice patterns and barriers they face to providing recommended therapies.</p> <p>Methods</p> <p>3 Focus groups among 29 primary care pediatricians in the San Francisco Bay Area were conducted. Transcripts were reviewed and coded into major themes by two investigators using modified grounded theory.</p> <p>Results</p> <p>Substantial changes in clinical practice have occurred since the emergence of CA-MRSA. These include increased office visits for SSTIs, patients with multiple recurrences and transmission within households. Additionally, our participants reported increased visits for mild skin problems due to media reports contributing to fears about CA-MRSA. Participants routinely prescribed antibiotics for SSTIs, however, few performed I&D. Few were aware of recent SSTI treatment recommendations. Barriers to prescribing antibiotics with CA-MRSA activity included concerns about side-effects and lack of local epidemiologic data showing that it is the primary etiology. Barriers to performing I&D included lack of training, resources and skepticism about its necessity. Important clinical challenges included increased time demands for follow-up visits and patient education along with the lack of evidence-based strategies for preventing recurrent inections and household transmission.</p> <p>Conclusion</p> <p>CA-MRSA has influenced the presentation and treatment of SSTIs especially in terms of case numbers and recurrences. Barriers to providing recommended therapies can be addressed through improved dissemination of treatment guidelines and epidemiologic data. Studies are urgently needed toimprove theevidence-base for treatment and prevention strategies.</p
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