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The purpose of this study was to determine whether arm circumference is predictive of arterial occlusion in the standing position and to determine the change in pressure before and immediately after exercise. Thirty-one participants had their arm circumference, blood pressure and standing arterial occlusion determined before exercise. Participants then completed elbow flexions at 40% of resting arterial occlusion at 30% of their one repetition maximum (1 RM). The goal repetitions for the exercise included one set of 30 repetitions followed by 3 sets of 15, with 30s rest between sets. Immediately following the last set, postexercise arterial occlusion was determined. Two different models of hierarchical linear regression were used to determine the greatest predictor of standing arterial occlusion. Our final model explained 69% of the variance in arterial occlusion with arm circumference (β = 0·639, part = 0·568) explaining more than brachial systolic blood pressure (β = 0·312, part = 0·277). Standing arterial occlusion increased from pre- [138 (15) mmHg] to post- [169 (20) mmHg] exercise ( P<0·001). In conclusion, the cardiovascular response to blood flow restriction ( BFR) in the upper arm following 4 sets of elbow flexion exercise decreases the relative arterial occlusion pressure. In addition, we confirm previous data that circumference explains the most unique variance in arterial occlusion pressure in the upper body. These findings are important as they provide additional insight into making the pressure more uniform between participants throughout exercise. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to investigate the acute and chronic skeletal muscle response to differing levels of blood flow restriction (BFR) pressure.Methods: Fourteen participants completed elbow flexion exercise with pressures from 40% to 90% of arterial occlusion. Pre/post torque measurements and electromyographic (EMG) amplitude of each set were quantified for each condition. This was followed by a separate 8-week training study of the effect of high (90% arterial occlusion) and low (40% arterial occlusion) pressure on muscle size and function.Results: For the acute study, decreases in torque were similar between pressures [-15.5 (5.9) Nm, P = 0.344]. For amplitude of the first 3 and last 3 reps there was a time effect. After training, increases in muscle size (10%), peak isotonic strength (18%), peak isokinetic torque (180°/s = 23%, 60°/s = 11%), and muscular endurance (62%) changed similarly between pressures.Conclusion: We suggest that higher relative pressures may not be necessary when exercising under BFR. [ABSTRACT FROM AUTHOR]

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This article discusses how the high demand for personal protective equipment during the COVID-19 pandemic can help draw attention to society's deep-seated reliance on forced labor. [ABSTRACT FROM AUTHOR]

This Viewpoint discusses the need for collaborative care among health care professionals to meet mental health demands in the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Following a decades long period of investigational dormancy, there is renewed interest in employing psychedelics as psychiatric treatments. The academic journals, institutions, and countries that have helped sustain clinical psychedelic research and the evolution of the literature on clinical studies of psychedelics have only recently begun to be investigated. To expand upon this work, we conducted a bibliometric analysis of clinical studies of 5-methoxy-N, N-dimethyltryptamine (5-MeO-DMT), ayahuasca, dimethyltryptamine (DMT), lysergic acid diethylamide (LSD), ibogaine, mescaline, 3,4-methylenedioxymethamphetamine (MDMA), and psilocybin published from 1965–2021. Our search revealed 394 relevant articles. After a lull from the 1970s-1990s, publications in this area have resurged. Studies most frequently focused on MDMA (49%), LSD (19%), psilocybin (18%), and ayahuasca (7%). A subanalysis of studies from 1965 to 2009 ("Older cohort") compared to 2010–2021 ("Recent cohort") revealed that the Recent cohort had a higher proportion of studies investigating psychedelics' therapeutic applications and a lower proportion of studies investigating the effects of psychedelics on people using them in non-research settings. Compared to the Older cohort, psilocybin studies increased proportionally in the Recent cohort, while DMT and mescaline studies decreased. Network analyses of inter-country collaborations suggested that psychedelic researchers in the United Kingdom have the most diverse international collaborations. [ABSTRACT FROM AUTHOR]

The ventral striatum (VS) is thought to signal the predicted value of expected outcomes. However, it is still unclear whether VS can encode value independently from variables often yoked to value such as response direction and latency. Expectations of high value reward are often associated with a particular action and faster latencies. To address this issue we trained rats to perform a task in which the size of the predicted reward was signaled before the instrumental response was instructed. Instrumental directional cues were presented briefly at a variable onset to reduce accuracy and increase reaction time. Rats were more accurate and slower when a large versus small reward was at stake. We found that activity in VS was high during odors that predicted large reward even though reaction times were slower under these conditions. In addition to these effects, we found that activity before the reward predicting cue reflected past and predicted reward. These results demonstrate that VS can encode value independent of motor contingencies and that the role of VS in goal-directed behavior is not just to increase vigor of specific actions when more is at stake. [ABSTRACT FROM AUTHOR]

The development of a topical microbicide blocking the sexual transmission of HIV-1 is urgently needed to control the global HIV/AIDS pandemic. The actinomycete-derived lectin actinohivin (AH) is highly specific to a cluster of high-mannose-type glycans uniquely found on the viral envelope (Env). Here, we evaluated AH's candidacy toward a microbicide in terms of in vitro anti-HIV-1 activity, potential side effects, and recombinant producibility. Two validated assay systems based on human peripheral blood mononuclear cell (hPBMC) infection with primary isolates and TZM-bl cell infection with Env-pseudotyped viruses were employed to characterize AH's anti-HIV-1 activity. In hPMBCs, AH exhibited nanomolar neutralizing activity against primary viruses with diverse cellular tropisms, but did not cause mitogenicity or cytotoxicity that are often associated with other anti-HIV lectins. In the TZM-bl-based assay, AH showed broad anti-HIV-1 activity against clinically-relevant, mucosally transmitting strains of clades B and C. By contrast, clade A viruses showed strong resistance to AH. Correlation analysis suggested that HIV-1′s AH susceptibility is significantly linked to the N-glycans at the Env C2 and V4 regions. For recombinant (r)AH expression, we evaluated a tobacco mosaic virus-based system in Nicotiana benthamiana plants as a means to facilitate molecular engineering and cost-effective mass production. Biochemical analysis and an Env-mediated syncytium formation assay demonstrated high-level expression of functional rAH within six days. Taken together, our study revealed AH's cross-clade anti-HIV-1 activity, apparent lack of side effects common to lectins, and robust producibility using plant biotechnology. These findings justify further efforts to develop rAH toward a candidate HIV-1 microbicide. [ABSTRACT FROM AUTHOR]

Background: Medicine is currently experiencing a "psychedelic renaissance", said by many to have commenced in 2006. Since then, clinical trials have consistently demonstrated promising findings for psychedelic-assisted therapies in the treatment of various mental health conditions and addictions. While most of this work has been privately funded, governmental biomedical research funding bodies in countries such as Australia, Canada, Israel, New Zealand, and the United Kingdom have begun supporting it. Given that the United States National Institutes of Health (NIH) is the largest public funder of biomedical research in the world, it is important to understand the degree to which the organization is supporting clinical trials of psychedelic-assisted therapies. We are unaware of existing literature quantifying direct NIH grant support for psychedelic-assisted therapy clinical trials, so we sought to answer this important question by searching all NIH grants awarded since the beginning of the psychedelic renaissance.Methods: We queried NIH RePORTER, NIH's grant database, for grants awarded from 2006-2020 mentioning the psychedelics 3,4-Methylenedioxymethamphetamine (MDMA), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT), ayahuasca, dimethyltryptamine (DMT), ibogaine, lysergic acid (LSD), mescaline, peyote, and psilocybin. We manually reviewed resulting grants to determine whether they directly funded psychedelic-assisted therapy clinical trials.Results: We identified zero NIH grants directly funding psychedelic-assisted therapy clinical trials during the study period.Conclusion: While governmental biomedical research funding bodies in other countries have begun funding clinical trials of psychedelic-assisted therapies during the psychedelic renaissance, NIH has yet to directly fund a single psychedelic-assisted therapy clinical trial. Concerns about risks related to psychedelics, a federal law preventing promotion of legalization of Schedule 1 drugs, and prioritization of grants for other types of studies on psychedelics may explain the dearth of NIH funding for psychedelic-assisted therapy clinical trials. [ABSTRACT FROM AUTHOR]