Insulin-A Probable Gross Molecular Structure Einstein, J. Ralph; McGavin, A. Stewart; Low, Barbara W.
Proceedings of the National Academy of Sciences - PNAS,
01/1963, Letnik:
49, Številka:
1
Journal Article
Abstract
Objective:
'Disuse' and 'Deconditioning' in relation to low back pain (LBP) are terms often used interchangeably. Discussions of 'disuse' refer to general physical inactivity, which evidence ...suggests does not differ between symptomatic and asymptomatic persons. 'Deconditioning' refers to a decrease in function, commonly both cardiovascular/aerobic fitness and muscular strength/endurance, again noting little difference. However, examination of decreased function relating specifically to lumbar extensor musculature deconditioning has yet to be examined, corroborating all possible methods. Thus, this review attempts to reappraise the deconditioning hypothesis in LBP, specifically considering lumbar extensor deconditioning.
Methods:
A literature review was conducted examining both cross-sectional and prospective data on specific lumbar extensor deconditioning and LBP. A narrative approach and 'snowballing' style literature search was used involving initial use of PubMed and Google Scholar databases searching up to December 2012. Included were studies utilizing the following three research methods, allowing specific induction of the role of such deconditioning; (1) strength/endurance testing of the isolated lumbar extensor musculature, (2) imaging and histochemical examination of the lumbar extensor musculature, and (3) fatigue testing of the lumbar extensor musculature using electromyography.
Results/findings:
Despite issues interpreting individual studies due to methods, the majority of evidence suggests LBP is associated with decreased strength/endurance, atrophy, and excessive fatigability of the lumbar extensors. Prospective studies also suggest lumbar extensor deconditioning may be a common risk factor predicting acute low back injury and LBP.
Conclusions:
The hypothesis of specific lumbar extensor deconditioning as being a causal factor in LBP is presently well supported. It is by no means the only causative factor and further research should more rigorously test this hypothesis addressing the methodological issues highlighted regarding previous studies. However, its role suggests specific exercise may be a worthwhile preventative and rehabilitative approach.
Abstract Objective Chronic low back pain (CLBP) is prevalent, costly, and acknowledged as multifactorial in nature. However, deconditioning of the lumbar extensor musculature may be a common factor. ...Thus specific resistance exercise is often recommended. Many resistance exercises for the lumbar extensors exist, although recent evidence suggests that isolated lumbar extension (ILEX) resistance training may best for conditioning these muscles. Thus this review aimed to examine the use of ILEX resistance training in participants with CLBP to provide a best-evidence synthesis for practitioners and clinicians. Literature Survey Reference lists from previous reviews were searched in addition to SPORTDiscus, PubMed, and Google Scholar databases up to May 2014 using search terms including combinations and synonyms of “isolation,” “lumbar extension,” “lumbar exercise,” “lumbar strength,” “lumbar endurance,” “lumbar spine,” “low back exercise,” “CLBP,” “pain,” and “disability.” Methodology A “snowballing”-style literature search was used that involved an emergent approach. Studies examining ILEX resistance training as an intervention in symptomatic CLBP populations reporting pain, disability, or global perceived outcomes (GPO) as outcomes were examined. Pain and disability were outcomes and were compared to consensus guidelines for minimal clinically important changes. Single case reports were excluded. Synthesis Results suggest that ILEX resistance training produces significant and meaningful improvements in perceived pain, disability, and GPOs, as part of a multiple intervention or stand-alone approach. A low frequency (once per week) yet high intensity of effort (to momentary muscular failure) approach using either full or limited range-of-motion ILEX resistance training appears to be sufficient and best for significant and meaningful outcomes. Limited comparative studies between ILEX resistance training and other specific exercise approaches exist; however, only limited evidence supports ILEX resistance training as being more effective. Conclusions These findings highlight ILEX resistance training as effective for significant and meaningful improvements in perceived pain, disability, and GPOs for CLBP participants. Further research should elucidate comparisons between ILEX resistance training and other specific exercise approaches and should clarify whether lumbar extensor conditioning is the mechanism responsible for the improvements reported.
Objectives/Hypothesis
Use of clinical questionnaires to assist in the screening of vestibular disorders in the acute hospital setting is needed. The objective is to detail the clinimetric properties ...and clinical utility of patient‐reported questionnaires for quantifying dizziness/vertigo symptoms associated with vestibular dysfunction, and to determine validity and utility for screening dizziness/vertigo in the emergency department.
Data Sources
We performed a systematic review of PubMed, CINAHL, Embase, and Web of Science in May 2015.
Methods
Two independent reviewers selected studies reporting clinimetric properties of patient‐reported questionnaires that aim to evaluate symptomology of dizziness/vertigo associated with vestibular dysfunction. A third reviewer resolved disparities. Of 1,901 articles initially found in the database search, 58 articles and 9 patient‐reported questionnaires were included.
Results
Clinimetric properties of content validity, criterion validity, internal consistency, inter‐/intrarater reliability, test–retest reliability, and responsiveness to vestibular rehabilitation are reported, and methodological quality is rated using the COSMIN (Consensus‐based Standards for the selection of health Measurement Instruments) checklist. Clinical utility is described in terms of target population, purpose, number of items, and whether the questionnaire was validated in the emergency department.
Conclusions
The Vestibular Rehabilitation Benefit Questionnaire, a relatively new tool, scored an “excellent” rating on three COSMIN criteria, and may be the best measure to address treatment outcomes. Questions on respective tools ranged from nine to 36, and no questionnaire was validated in the emergency department. Due to the number of questions and lack of validity, none of the questionnaires was deemed appropriate as a screening tool for dizziness/vertigo in the emergency department. Laryngoscope, 128:971–981, 2018
Global control of COVID-19 requires broadly accessible vaccines that are effective against SARS-CoV-2 variants. In this report, we exploit the immunostimulatory properties of bacille Calmette-Guérin ...(BCG), the existing tuberculosis vaccine, to deliver a vaccination regimen with potent SARS-CoV-2-specific protective immunity. Combination of BCG with a stabilised, trimeric form of SARS-CoV-2 spike antigen promoted rapid development of virus-specific IgG antibodies in the blood of vaccinated mice, that was further augmented by the addition of alum. This vaccine formulation, BCG:CoVac, induced high-titre SARS-CoV-2 neutralising antibodies (NAbs) and Th1-biased cytokine release by vaccine-specific T cells, which correlated with the early emergence of T follicular helper cells in local lymph nodes and heightened levels of antigen-specific plasma B cells after vaccination. Vaccination of K18-hACE2 mice with a single dose of BCG:CoVac almost completely abrogated disease after SARS-CoV-2 challenge, with minimal inflammation and no detectable virus in the lungs of infected animals. Boosting BCG:CoVac-primed mice with a heterologous vaccine further increased SARS-CoV-2-specific antibody responses, which effectively neutralised B.1.1.7 and B.1.351 SARS-CoV-2 variants of concern. These findings demonstrate the potential for BCG-based vaccination to protect against major SARS-CoV-2 variants circulating globally.
Resistance exercise may acutely enhance muscle contractile activity, which is known as postactivation potentiation (PAP). Postactivation potentiation augments important skills that require power ...production that are necessary during soccer performance. The aim of this study was to determine the optimal recovery time to elicit PAP after a bout of high-intensity resistance exercise in professional soccer players. Twenty-two senior professional soccer players (mean SD; age, 23 4.5 years; stature, 1.83 6.6 m; body mass, 80.9 7.8 kg) were randomized to either an experimental (n = 11) or a control group (n = 11). Both groups performed a standardized warm-up and baseline countermovement jump (CMJ) followed by a 10-minute recovery. The control group then performed a CMJ at 15 seconds and at 4, 8, 12, 16, and 20 minutes, whereas the experimental group performed a 3 repetition maximum (RM) squat and then an identical CMJ protocol. No significant differences were found between the groups for CMJ peak power (p > 0.05) or jump height (p > 0.05). No time effect for peak power (F(6,60) = 2.448; p = 0.063) or jump height (F(6,60) = 2.399; p = 0.089) was observed throughout the experimental group trials. Responders (n = 6) displayed individualized PAP profiles at 4 (n = 3), 12 (n = 1), and 16 (n = 2) minutes after conditioning contraction, whereas nonresponders (n = 5) did not. A set of 3RM squats failed to acutely potentiate all participants CMJ performance. Both PAP responders and nonresponders were identified and have individualized PAP time constants. This is not consistent with the previous literature, which used identical protocols. Strength and conditioning practitioners need to individualize recovery "windows" and identify athletes who respond to PAP before undertaking a complex training intervention.
Antidepressants are increasingly recognized to have anti-inflammatory properties in addition to their ability to treat major depressive disorders. To explore if engagement of 5-hydroxytryptamine ...(5-HT) receptors was required for the anti-inflammatory effect of the tetracyclic antidepressant mianserin, a series of structural derivatives were generated with the aim of reducing 5-HT receptor binding. Primary human peripheral blood mononuclear cells were used to screen for anti-inflammatory activity. The lead compound demonstrated a significant loss in 5-HT receptor binding, as assessed by non-selective 5-HT binding of radiolabelled serotonin in rat cerebral cortex. However, it retained the ability to inhibit endosomal toll-like receptor 8 signaling in primary human macrophages and spontaneous cytokine production from human rheumatoid synovial tissue equivalent to that previously observed for mianserin. These data demonstrate that the anti-inflammatory mechanism of mianserin may be independent of 5-HT receptor activity. This research offers new insights into the mechanism and structural requirements for the anti-inflammatory action of mianserin.
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