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The photoenzyme protochlorophyllide oxidoreductase (POR) is an important enzyme for understanding biological H‐transfer mechanisms. It uses light to catalyse the reduction of protochlorophyllide to chlorophyllide, a key step in chlorophyll biosynthesis. Although a wealth of spectroscopic data have provided crucial mechanistic insight, a structural rationale for POR photocatalysis has proved challenging and remains hotly debated. Recent structural models of the ternary enzyme–substrate complex, derived from crystal and electron microscopy data, show differences in the orientation of the protochlorophyllide substrate and the architecture of the POR active site, with significant implications for the catalytic mechanism. Here, we use a combination of computational and experimental approaches to investigate the compatibility of each structural model with the hypothesised reaction mechanisms and propose an alternative structural model for the cyanobacterial POR ternary complex. We show that a strictly conserved tyrosine, previously proposed to act as the proton donor in POR photocatalysis, is unlikely to be involved in this step of the reaction but is crucial for Pchlide binding. Instead, an active site cysteine is important for both hydride and proton transfer reactions in POR and is proposed to act as the proton donor, either directly or through a water‐mediated network. Moreover, a conserved glutamine is important for Pchlide binding and ensuring efficient photochemistry by tuning its electronic properties, likely by interacting with the central Mg atom of the substrate. This optimal 'binding pose' for the POR ternary enzyme–substrate complex illustrates how light energy can be harnessed to facilitate enzyme catalysis by this unique enzyme. [ABSTRACT FROM AUTHOR]

As physical therapists and exercise professionals, we have an obligation to promote health and well-being through participation in sport and recreational/physical activity. We play an active role in facilitating and encouraging movement for a large percentage of the population, including our transgender patients/clients. It is integral that we include transgender individuals in supportive and inclusive atmospheres of play, and it is critical for us to lead the conversation around the inclusion of the transgender community in recreational activities and sport. This commentary provides evidence for the physical therapy community to support, advocate for, and include all populations as we promote healthy habits through sport. [ABSTRACT FROM AUTHOR]

Simple Summary: Evidence-based medicine uses healthcare professional experience, research evidence, and patient preferences to support the best decisions in healthcare. Within this manuscript we outline the different ways that research methods and infrastructure have been developed to help support evidence-based decision-making in rhabdomyosarcoma. We discuss key issues in various areas including involving families in the research process, selecting aspects of the research design (topics and outcomes), drawing research together (evidence synthesis and guideline development), sharing research findings, and supporting research processes (including research about research). The foundations of evidence-based practice are the triad of patient values and preferences, healthcare professional experience, and best available evidence, used together to inform clinical decision-making. Within the field of rhabdomyosarcoma, collaborative groups such as the European Paediatric Soft Tissue Sarcoma Group (EpSSG) have worked to develop evidence to support this process. We have explored many of the key research developments within this review, including patient and public involvement, decision-making research, research into areas other than drug development, core outcome sets, reporting and dissemination of research, evidence synthesis, guideline development and clinical decision rules, research of research methodologies, and supporting research in RMS. [ABSTRACT FROM AUTHOR]

Background: Relapse and recurrence of depression are common, contributing to the overall burden of depression globally. Accurate prediction of relapse or recurrence while patients are well would allow the identification of high-risk individuals and may effectively guide the allocation of interventions to prevent relapse and recurrence.Aims: To review prognostic models developed to predict the risk of relapse, recurrence, sustained remission, or recovery in adults with remitted major depressive disorder.Method: We searched the Cochrane Library (current issue); Ovid MEDLINE (1946 onwards); Ovid Embase (1980 onwards); Ovid PsycINFO (1806 onwards); and Web of Science (1900 onwards) up to May 2021. We included development and external validation studies of multivariable prognostic models. We assessed risk of bias of included studies using the Prediction model risk of bias assessment tool (PROBAST).Results: We identified 12 eligible prognostic model studies (11 unique prognostic models): 8 model development-only studies, 3 model development and external validation studies and 1 external validation-only study. Multiple estimates of performance measures were not available and meta-analysis was therefore not necessary. Eleven out of the 12 included studies were assessed as being at high overall risk of bias and none examined clinical utility.Conclusions: Due to high risk of bias of the included studies, poor predictive performance and limited external validation of the models identified, presently available clinical prediction models for relapse and recurrence of depression are not yet sufficiently developed for deploying in clinical settings. There is a need for improved prognosis research in this clinical area and future studies should conform to best practice methodological and reporting guidelines. [ABSTRACT FROM AUTHOR]