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As limited research has focused on the physiological responses associated with cricket activity, the aim of this pilot study was to measure selected physiological responses during batting in a simulated high-scoring 1-day cricket game. Ten male university cricketers performed a batting specific work bout consisting of four sprints per over (six balls) for a seven over period. Testing was conducted outdoors with players wearing full batting gear. All experimentation was conducted under temperate environmental conditions. During the simulated work bout, a portable on-line metabolic system (the k4b(2)) was attached to the subjects for the continuous assessment of selected physiological variables including heart rate (HR), ventilation (F(B), V(T) and V(E)), oxygen uptake (V(O2)) and metabolic carbon dioxide (V(CO2)) production. Energy expenditure was calculated from the oxygen consumption responses and substrate use was calculated from the V(O2)/V(CO2) responses. The results demonstrate that although the first over carried a statistically (p<0.05) lower energetic cost than the remaining six overs, most physiological responses stabilised thereafter. This excluded the heart rate responses which increased significantly (p<0.05) during the first three overs after which marginal increases were observed with no statistical difference between the last four overs (heart rate ranged from 149+/-19bt min(-1) in the fourth over to 155+/-18bt min(-1) in the last over). There was a mean energy expenditure of 2536kJh(-1) over the duration of the work bout. [ABSTRACT FROM AUTHOR]

There is a need for psychometrically sound measures of children's participation in recreation and leisure activities, for both clinical and research purposes. This paper provides information about the construct validity of the Children's Assessment of Participation and Enjoyment (CAPE) and its companion measure, Preferences for Activities of Children (PAC). These measures are appropriate for children and youth with and without disabilities between the ages of 6 and 21 years. They provide information about six dimensions of participation (i.e. diversity, intensity, where, with whom, enjoyment and preference) and two categories of recreation and leisure activities: (i) formal and informal activities; and (ii) five types of activities (recreational, active physical, social, skill-based and self-improvement). This paper presents information about the performance of the CAPE and PAC activity type scores using data from a study involving 427 children with physical disabilities between the ages of 6 and 15 years. Intensity, enjoyment and preference scores were significantly correlated with environmental, family and child variables, in expected ways. Predictions also were supported with respect to differences in mean scores for boys vs. girls, and children in various age groups. The information substantiates the construct validity of the measures. The clinical and research utility of the measures are discussed. [ABSTRACT FROM AUTHOR]

This article reviews the effectiveness of the 10 main strategies used to provide transition education and planning services for youth with disabilities. The review suggests that multifaceted interventions are most effective. Integrated and comprehensive transition services should address skill instruction and self-awareness; provide customized informational, emotional, and instrumental supports to meet the needs of youth and families; provide direct opportunities and experiences for skill development; and address the welcoming nature of community activities and settings. The information can be used by rehabilitation managers and therapists in the design and delivery of transition services. Recommendations are made for future research with respect to strategies to facilitate youth transitions. [ABSTRACT FROM AUTHOR]

This article describes the use and utility of the Life Needs Model of Pediatric Service Delivery at a regional children's rehabilitation center. The model is a transdisciplinary, evidence-based model that guides pediatric service delivery to meet the long-range goals of community participation and quality of life for children and youth with disabilities. The article describes the use of the model as a tool to assist with the development of organizational culture, strategic and operational planning, the development of therapists' expertise, and the development of community partnerships. The model also has influenced human resources practices, community relations activities, and research. The model provides needed direction to service planners about the types of services that are important to provide in a geographical region, and fills a gap in outlining the nature of services that can be encompassed in pediatric rehabilitation. [ABSTRACT FROM AUTHOR]

This article provides a conceptual model and review of the effectiveness of approaches for providing transition education and planning services for youth with disabilities. The model incorporates four approaches: skills training, prevocational/ vocational guidance, a client-centered approach, and an ecological/experiential approach. The model links these approaches to commonly used transition strategies, which reflect the personal, person-environment, and environmental levels of intervention. The model specifies the short-term goals addressed by the approaches and strategies and links these to the long-term outcome of multifaceted role engagement. Evidence for the effectiveness and utility of the identified approaches is reviewed. Recommendations are made for best practices in the delivery of transition education and planning services, for research, and for clinical practice. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the validity of five physical activity monitors available for research: the CSA, the TriTrac-R3D, the RT3, the SenseWear Armband, and the BioTrainer-Pro. METHODS: A total of 10 healthy men and 11 healthy women performed 10 min of treadmill walking at 54, 80, and 107 mxmin and treadmill running at 134, 161, 188, and 214 mxmin. The CSA, TriTrac-R3D, RT3, and BioTrainer-Pro accelerometers were placed side by side bilaterally at the waist in the axillary position, and the SenseWear Armband monitors were placed bilaterally on the posterior portion of each arm in the mid-humeral position. Simultaneous measurements of body motion and indirect calorimetry were continuously recorded during all exercise. Data were analyzed with repeated measures ANOVA and pairwise Bonferroni-adjusted estimated marginal means. RESULTS:: There was no significant difference in the mean energy expenditure (EE) recorded bilaterally by any of the monitors (P < 0.05) at any treadmill speed. The SenseWear Armband, the TriTrac-R3D, and the RT3 had significant increases in mean EE across all walking and running speeds (P < 0.05). Below 161 mxmin, the mean EE recorded by the BioTrainer-Pro and the CSA increased significantly (P < 0.001); however, there was no significant difference (P > 0.10) in mean EE recorded by either monitor for speeds above 161 mxmin. In general, all monitors overestimated EE at most treadmill speeds when compared with indirect calorimetry (P < 0.001), except for the CSA which underestimated EE at the lowest and highest speeds. CONCLUSION: The CSA was the best estimate of total EE at walking and jogging speeds, the TriTrac-R3D was the best estimate of total EE at running speeds, and the SenseWear Armband was the best estimate of total EE at most speeds. [ABSTRACT FROM AUTHOR]

This study documents the development of hand and upper-extremity function in young children who have cerebral palsy (CP) with upper-extremity involvement using longitudinal data. Assessments of hand function and the quality of upper-extremity movement were conducted on 29 males and 22 females (mean age 36.2 months, SD 10.6; age range 16 to 60 months at baseline) and on four other occasions over 10 months. Linear mixed effects modeling was used to estimate average developmental curves and the degree of individual differences in the patterns of development which were conditional on the body-site distribution of CP and severity of impairments. Results indicate that hand function in this clinical population develops differently from overall upper-extremity skills with declines in function in upper-extremity skills being more common and pronounced among older children. However, there is substantial interindividual variation. Distribution of CP and severity of impairments were significant predictors of development. Results are discussed in terms of their clinical implications. [ABSTRACT FROM AUTHOR]

The Measure of Processes of Care for Service Providers (MPOG-SP) is a 27-item self-assessment questionnaire for pediatric caregivers, designed to measure their reported implementation of family-centered service (FCS). The MPOG-SP was adapted from the well-validated and widely used measure in pediatric rehabilitation, the Measure of Processes of Care. In this article we describe the development, field testing, properties, and utility of this instrument.Four MPOC-SP factors were generated by exploratory factor analysis; each factor addresses a distinct facet of FCS (Cronbach's alpha for these scales is .86, .88, .76, and .84). Validity analyses revealed that MPOC-SP scale scores discriminate between reported caregiving behaviors and ideal levels of FCS implementation, and also reflect cross-discipline differences in professional roles. It is expected that the MPOC-SP will be useful in the program evaluations, research initiatives, and professional development endeavors. [ABSTRACT FROM AUTHOR]

Abstract Background Family social support, as a form of social capital, contributes to social health disparities at different age of life. In a life-course epidemiological perspective, the aims of our study were to examine the association between self-reported family social environment during childhood and self-reported health in young adulthood and to assess the role of family functioning during childhood as a potential mediating factor in explaining the association between family breakup in childhood and self-reported health in young adulthood. Methods We analyzed data from the first wave of the Health, Inequalities and Social Ruptures Survey (SIRS), a longitudinal health and socio-epidemiological survey of a random sample of 3000 households initiated in the Paris metropolitan area in 2005. Sample-weighted logistic regression analyses were performed to determine the association between the quality of family social environment in childhood and self-rated health (overall health, physical health and psychological well-being) in young adults (n = 1006). We used structural equation model to explore the mediating role of the quality of family functioning in childhood in the association between family breakup in childhood and self-rated health in young adulthood. Results The multivariate results support an association between a negative family social environment in childhood and poor self-perceived health in adulthood. The association found between parental separation or divorce in childhood and poor self-perceived health in adulthood was mediated by parent-child relationships and by having witnessed interparental violence during childhood. Conclusion These results argue for interventions that enhance family cohesion, particularly after family disruptions during childhood, to promote health in young adulthood.

Abstract Background Verbal autopsy analyses are widely used for estimating cause-specific mortality rates (CSMR) in the vast majority of the world without high-quality medical death registration. Verbal autopsies -- survey interviews with the caretakers of imminent decedents -- stand in for medical examinations or physical autopsies, which are infeasible or culturally prohibited. Methods and Findings We introduce methods, simulations, and interpretations that can improve the design of automated, data-derived estimates of CSMRs, building on a new approach by King and Lu (2008). Our results generate advice for choosing symptom questions and sample sizes that is easier to satisfy than existing practices. For example, most prior effort has been devoted to searching for symptoms with high sensitivity and specificity, which has rarely if ever succeeded with multiple causes of death. In contrast, our approach makes this search irrelevant because it can produce unbiased estimates even with symptoms that have very low sensitivity and specificity. In addition, the new method is optimized for survey questions caretakers can easily answer rather than questions physicians would ask themselves. We also offer an automated method of weeding out biased symptom questions and advice on how to choose the number of causes of death, symptom questions to ask, and observations to collect, among others. Conclusions With the advice offered here, researchers should be able to design verbal autopsy surveys and conduct analyses with greatly reduced statistical biases and research costs.

Abstract Background Incomplete information on death certificates makes recorded cause-of-death data less useful for public health monitoring and planning. Certifying physicians sometimes list only the mode of death without indicating the underlying disease or diseases that led to the death. Inconsistent cause-of-death assignment among cardiovascular causes of death is of particular concern. This can prevent valid epidemiologic comparisons across countries and over time. Methods We propose that coarsened exact matching be used to infer the underlying causes of death where only the mode of death is known. We focus on the case of heart failure in US, Mexican, and Brazilian death records. Results Redistribution algorithms derived using this method assign the largest proportion of heart failure deaths to ischemic heart disease in all three countries (53%, 26%, and 22% respectively), with larger proportions assigned to hypertensive heart disease and diabetes in Mexico and Brazil (16% and 23% vs. 7% for hypertensive heart disease, and 13% and 9% vs. 6% for diabetes). Reassigning these heart failure deaths increases the US ischemic heart disease mortality rate by 6%. Conclusions The frequency with which physicians list heart failure in the causal chain for various underlying causes of death allows for inference about how physicians use heart failure on the death certificate in different settings. This easy-to-use method has the potential to reduce bias and increase comparability in cause-of-death data, thereby improving the public health utility of death records.

Abstract Background Studies have revealed large variations in average health status across social, economic, and other groups. No study exists on the distribution of the risk of ill-health across individuals, either within groups or across all people in a society, and as such a crucial piece of total health inequality has been overlooked. Some of the reason for this neglect has been that the risk of death, which forms the basis for most measures, is impossible to observe directly and difficult to estimate. Methods We develop a measure of total health inequality – encompassing all inequalities among people in a society, including variation between and within groups – by adapting a beta-binomial regression model. We apply it to children under age two in 50 low- and middle-income countries. Our method has been adopted by the World Health Organization and is being implemented in surveys around the world; preliminary estimates have appeared in the World Health Report (2000). Results Countries with similar average child mortality differ considerably in total health inequality. Liberia and Mozambique have the largest inequalities in child survival, while Colombia, the Philippines and Kazakhstan have the lowest levels among the countries measured. Conclusions Total health inequality estimates should be routinely reported alongside average levels of health in populations and groups, as they reveal important policy-related information not otherwise knowable. This approach enables meaningful comparisons of inequality across countries and future analyses of the determinants of inequality.

Abstract Background Prostanoids are known to participate in the process of fibrogenesis. Because lung fibroblasts produce prostanoids and are believed to play a central role in the pathogenesis of idiopathic pulmonary fibrosis (IPF), we hypothesized that fibroblasts (HF) cultured from the lungs of patients with IPF (HF-IPF) have an altered balance between profibrotic (thromboxane [TX]A2) and antifibrotic (prostacyclin [PGI2]) prostaglandins (PGs) when compared with normal human lung fibroblasts (HF-NL). Methods We measured inducible cyclooxygenase (COX)-2 gene and protein expression, and a profile of prostanoids at baseline and after IL-1β stimulation. Results In both HF-IPF and HF-NL COX-2 expression was undetectable at baseline, but was significantly upregulated by IL-1β. PGE2 was the predominant COX product in IL-1β-stimulated cells with no significant difference between HF-IPF and HF-NL (28.35 [9.09–89.09] vs. 17.12 [8.58–29.33] ng/106 cells/30 min, respectively; P = 0.25). TXB2 (the stable metabolite of TXA2) production was significantly higher in IL-1β-stimulated HF-IPF compared to HF-NL (1.92 [1.27–2.57] vs. 0.61 [0.21–1.64] ng/106 cells/30 min, respectively; P = 0.007) and the ratio of PGI2 (as measured by its stable metabolite 6-keto-PGF1α) to TXB2 was significantly lower at baseline in HF-IPF (0.08 [0.04–0.52] vs. 0.12 [0.11–0.89] in HF-NL; P = 0.028) and with IL-1β stimulation (0.24 [0.05–1.53] vs. 1.08 [0.51–3.79] in HF-NL; P = 0.09). Conclusion An alteration in the balance of profibrotic and antifibrotic PGs in HF-IPF may play a role in the pathogeneses of IPF.

Cell division presents a challenge for eukaryotic cells: how can chromosomes effectively segregate within the confines of a membranous nuclear compartment? Different organisms have evolved diverse solutions by modulating the degree of nuclear compartmentalization, ranging from complete nuclear envelope breakdown to complete maintenance of nuclear compartmentalization via nuclear envelope expansion. Many intermediate forms exist between these extremes, suggesting that nuclear dynamics during cell division are surprisingly plastic. In this review, we highlight the evolutionary diversity of nuclear divisions, focusing on two defining characteristics: (1) chromosome compartmentalization and (2) nucleocytoplasmic transport. Further, we highlight recent evidence that nuclear behavior during division can vary within different cellular contexts in the same organism. The variation observed within and between organisms underscores the dynamic evolution of nuclear divisions tailored to specific contexts and cellular requirements. In-depth investigation of diverse nuclear divisions will enhance our understanding of the nucleus, both in physiological and pathological states.

Background : Schizophrenia (SZ) is a multifactorial chronic psychiatric disorder with a worldwide prevalence of 1%. Altered expression of PLCβ occurs in SZ patients, suggesting alterations in the PLCβ/IP 3 /Ca 2+ signaling pathway. This cascade regulates critical cellular processes in all cell types, including the neuronal lineage; however, there is scarce evidence regarding the functionality of this transduction signaling in neuronal cells derived from SZ patients. Objective : We evaluated the functionality of the PLCβ/IP 3 /Ca 2+ pathway in olfactory neuronal precursor cells (hONPCs) obtained from SZ patients. Methods : Cryopreserved hONPCs isolated from SZ patients and healthy subjects (HS) were thawed. The cellular types in subcultures were corroborated by immunodetection of the multipotency and lineage markers SOX-2, Musashi-1, nestin, and β-III tubulin. The PLCβ/IP 3 /Ca 2+ pathway was activated by GPCR (G q ) ligands (ATP, UTP, serotonin, and epinephrine). In addition, PLCβ and IP 3 R were directly stimulated by perfusing cells with the activators m-3M3FBS and ADA, respectively. Cytosolic Ca 2+ was measured by microfluorometry and by Ca 2+ imaging. The amount and subcellular distribution of the PLCβ1 and PLCβ3 isoforms were evaluated by confocal immunofluorescence. IP 3 concentration was measured by ELISA. Results : The results show that the increase of cytosolic Ca 2+ triggered by GPCR ligands or directly through either PLCβ or IP 3 R activation was significantly lower in SZ-derived hONPCs, regarding HS-derived cells. Moreover, the relative amount of the PLCβ1 and PLCβ3 isoforms and IP 3 production stimulated with m-3M3FBS were reduced in SZ-derived cells. Conclusions : Our results suggest an overall functional impairment in the PLCβ/IP 3 /Ca 2+ signaling pathway in SZ-derived hONPCs.

About 3 billion new tires are produced each year and about 800 million tires become waste annually. Global dependence upon tires produced from natural rubber and petroleum-based compounds represents a persistent and complex environmental problem with only partial and often-times, ineffective solutions. Tire emissions may be in the form of whole tires, tire particles, and chemical compounds, each of which is transported through various atmospheric, terrestrial, and aquatic routes in the natural and built environments. Production and use of tires generates multiple heavy metals, plastics, PAH's, and other compounds that can be toxic alone or as chemical cocktails. Used tires require storage space, are energy intensive to recycle, and generally have few post-wear uses that are not also potential sources of pollutants (e.g., crumb rubber, pavements, burning). Tire particles emitted during use are a major component of microplastics in urban runoff and a source of unique and highly potent toxic substances. Thus, tires represent a ubiquitous and complex pollutant that requires a comprehensive examination to develop effective management and remediation. We approach the issue of tire pollution holistically by examining the life cycle of tires across production, emissions, recycling, and disposal. In this paper, we synthesize recent research and data about the environmental and human health risks associated with the production, use, and disposal of tires and discuss gaps in our knowledge about fate and transport, as well as the toxicology of tire particles and chemical leachates. We examine potential management and remediation approaches for addressing exposure risks across the life cycle of tires. We consider tires as pollutants across three levels: tires in their whole state, as particulates, and as a mixture of chemical cocktails. Finally, we discuss information gaps in our understanding of tires as a pollutant and outline key questions to improve our knowledge and ability to manage and remediate tire pollution., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

This study explored the acceptability of Children and Teens in Charge of their Health (CATCH), a program for children with spina bifida or cerebral palsy to enhance their physical activity and diet. Qualitative interviews were conducted with children ( n  = 6) and their parents ( n  = 6) who participated in CATCH. Analysis used an environmental systems framework. Microsystem factors impacting acceptability of the program were: Children's motivations for change, their age, and their physical health. Mesosystem factors were: Use of virtual coaching and the relationship between coach and child. Macrosystem factors (e.g. Covid-19), did not impact acceptability, but affected some goal attainment strategies. CATCH was broadly acceptable to children and parents and shows promise as a health promotion program tailored to children with disabilities. An environmental systems framework can potentially help other health promotion programs enhance their acceptability and success.

Periarticular infiltration following total knee and hip arthroplasty has been demonstrated to be equivalent to peripheral nerve blocks for postoperative pain management. The ideal cocktail has not been established yet. We have conducted a literature search on PubMed and Embase. Our search criteria included randomized controlled trials (RCTs) and systematic reviews (SRs). We tried to only include the most recent studies to keep the information current. The included research focused at Dexmedetomidine, Liposomal Bupivacaine, Ropivacaine, Epinephrine, Ketorolac, Morphine, Ketamine and Glucocorticosteroids. Each medication's mode of action, duration, ideal dosage, contraindications, side effects and effectiveness have been summarized in the review article. This article will help the clinician to make an informed evidence-based decision about which medications to include in their ideal cocktail., (© 2023. Crown.)

Basic Multicellular Units (BMUs) conduct bone remodeling, a critical process of tissue turnover which, if imbalanced, can lead to disease, including osteoporosis. Parathyroid hormone (PTH 1-34; Teriparatide) is an osteoanabolic treatment for osteoporosis; however, it elevates the rate of intra-cortical remodeling (activation frequency) leading, at least transiently, to increased porosity. The purpose of this study was to test the hypothesis that PTH not only increases the rate at which cortical BMUs are initiated but also increases their progression (Longitudinal Erosion Rate; LER). Two groups (n = 7 each) of six-month old female New Zealand white rabbits were both administered 30 μg/kg of PTH once daily for a period of two weeks to induce remodeling. Their distal right tibiae were then imaged in vivo by in-line phase contrast micro-CT at the Canadian Light Source synchrotron. Over the following two weeks the first group (PTH) received continued daily PTH while the second withdrawal group (PTHW) was administrated 0.9 % saline. At four weeks all animals were euthanized, their distal tibiae were imaged by conventional micro-CT ex vivo and histomorphometry was performed. Matching micro-CT datasets (in vivo and ex vivo) were co-registered in 3D and LER was measured from 612 BMUs. Counter to our hypothesis, mean LER was lower (p < 0.001) in the PTH group (30.19 ± 3.01 μm/day) versus the PTHW group (37.20 ± 2.77 μm/day). Despite the difference in LER, osteonal mineral apposition rate (On.MAR) did not differ between groups indicating the anabolic effect of PTH was sustained after withdrawal. The slowing of BMU progression by PTH warrants further investigation; slowed resorption combined with elevated bone formation rate, may play an important role in how PTH enhances coupling between resorption and formation within the BMU. Finally, the prolonged anabolic response following withdrawal may have utility in terms of optimizing clinical dosing regimens., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

CRISPR-Cas9 is a powerful gene-editing technology; however, off-target activity remains an important consideration for therapeutic applications. We have previously shown that force-stretching DNA induces off-target activity and hypothesized that distortions of the DNA topology in vivo, such as negative DNA supercoiling, could reduce Cas9 specificity. Using single-molecule optical-tweezers, we demonstrate that negative supercoiling λ-DNA induces sequence-specific Cas9 off-target binding at multiple sites, even at low forces. Using an adapted CIRCLE-seq approach, we detect over 10,000 negative-supercoiling-induced Cas9 off-target double-strand breaks genome-wide caused by increased mismatch tolerance. We further demonstrate in vivo that directed local DNA distortion increases off-target activity in cells and that induced off-target events can be detected during Cas9 genome editing. These data demonstrate that Cas9 off-target activity is regulated by DNA topology in vitro and in vivo, suggesting that cellular processes, such as transcription and replication, could induce off-target activity at previously overlooked sites., Competing Interests: Declaration of interests S.J.B. is co-founder and VP Science Strategy at Artios Pharma Ltd and is on the Molecular Cell advisory board. G.A.K. is lead inventor on a patent (EP3737756B1) for the ODS method used to generate negatively supercoiled DNA, which is licensed to LUMICKS B.V., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Proper monitoring of fatigue and muscular damage may be used to decrease the high levels of cardiovascular disease, overuse musculoskeletal injuries, and workers compensation claims within the profession of firefighting. The purpose of this study was to examine muscle damage, muscular fatigue, and inflammation responses following a typical firefighting shift. Twenty-four professional firefighters completed two Physical Ability Tests to standardize the tasks typically performed in a day of work, and to elicit similar physiological responses. Participants were then monitored for 48 h. Prior to, and 48 h following the Physical Ability Tests, participants were evaluated for changes in strength, power, range-of-motion, as well as blood markers including myoglobin and c-reactive protein. Following the Physical Ability Tests, significant differences in myoglobin ( p < 0.05), grip strength ( p < 0.05), vertical jump ( p < 0.05), and sit-and-reach ( p < 0.05) were observed. No difference in c-reactive protein was observed ( p > 0.05). After 24 hours following a shift, firefighters exhibited decreased strength, power, and range-of-motion. This may lead to decreases in performance and an increased risk of injury.

Nuclear pore complexes (NPCs) are large proteinaceous assemblies that mediate nuclear compartmentalization. NPCs undergo large-scale structural rearrangements during mitosis in metazoans and some fungi. However, our understanding of NPC remodeling beyond mitosis remains limited. Using time-lapse fluorescence microscopy, we discovered that NPCs undergo two mechanistically separable remodeling events during budding yeast meiosis in which parts or all of the nuclear basket transiently dissociate from the NPC core during meiosis I and II, respectively. Meiosis I detachment, observed for Nup60 and Nup2, is driven by Polo kinase-mediated phosphorylation of Nup60 at its interface with the Y-complex. Subsequent reattachment of Nup60-Nup2 to the NPC core is facilitated by a lipid-binding amphipathic helix in Nup60. Preventing Nup60-Nup2 reattachment causes misorganization of the entire nuclear basket in gametes. Strikingly, meiotic nuclear basket remodeling also occurs in the distantly related fission yeast, Schizosaccharomyces pombe. Our study reveals a conserved and developmentally programmed aspect of NPC plasticity, providing key mechanistic insights into the nuclear basket organization., (© 2022 King et al.)

In anaphase, any unresolved DNA entanglements between the segregating sister chromatids can give rise to chromatin bridges. To prevent genome instability, chromatin bridges must be resolved prior to cytokinesis. The SNF2 protein PICH has been proposed to play a direct role in this process through the remodeling of nucleosomes. However, direct evidence of nucleosome remodeling by PICH has remained elusive. Here, we present an in vitro single-molecule assay that mimics chromatin under tension, as is found in anaphase chromatin bridges. Applying a combination of dual-trap optical tweezers and fluorescence imaging of PICH and histones bound to a nucleosome-array construct, we show that PICH is a tension- and ATP-dependent nucleosome remodeler that facilitates nucleosome unwrapping and then subsequently slides remaining histones along the DNA. This work elucidates the role of PICH in chromatin-bridge dissolution, and might provide molecular insights into the mechanisms of related SNF2 proteins., (© 2022. The Author(s).)

Melatonin (MEL), an indolamine with diverse functions in the brain, has been shown to produce antidepressant-like effects, presumably through stimulating neurogenesis. We recently showed that the combination of MEL with ketamine (KET), an NMDA receptor antagonist, has robust antidepressant-like effects in mice, at doses that, by themselves, are non-effective and have no adverse effects. Here, we show that the KET/MEL combination increases neurogenesis in a clone derived from human olfactory neuronal precursors, a translational pre-clinical model for effects in the human CNS. Neurogenesis was assessed by the formation of cell clusters > 50 µm in diameter, positively stained for nestin, doublecortin, BrdU and Ki67, markers of progenitor cells, neurogenesis, and proliferation. FGF, EGF and BDNF growth factors increased the number of cell clusters in cultured, cloned ONPs. Similarly, KET or MEL increased the number of clusters in a dose-dependent manner. The KET/MEL combination further increased the formation of clusters, with a maximal effect obtained after a triple administration schedule. Our results show that the combination of KET/MEL, at subeffective doses that do not produce adverse effects, stimulate neurogenesis in human neuronal precursors. Moreover, the mechanism by which the combination elicits neurogenesis is meditated by melatonin receptors, CaM Kinase II and CaM antagonism. This could have clinical advantages for the fast treatment of depression.

Supplementation with cannabidiol (CBD) may expedite recovery when consumed after exercise. The purpose of this study was to determine if supplementation with CBD reduces inflammation and enhances performance following strenuous eccentric exercise in collegiate athletes. Twenty-four well-trained females (age = 21.2 ± 1.8 years, height = 166.4 ± 8 cm, weight = 64.9 ± 9.1 kg) completed 100 repetitions of unilateral eccentric leg extension to induce muscle damage. In this crossover design, participants were randomized to receive 5 mg/kg of CBD in pill form or a placebo 2 h prior to, immediately following, and 10 h following muscle damage. Blood was collected, and performance and fatigue were measured prior to, and 4 h, 24 h, and 48 h following the muscle damage. Approximately 28 days separated treatment administration to control for the menstrual cycle. No significant differences were observed between the treatments for inflammation, muscle damage, or subjective fatigue. Peak torque at 60°/s ( p = 0.001) and peak isometric torque ( p = 0.02) were significantly lower 24 h following muscle damage, but no difference in performance was observed between treatments at any timepoint. Cannabidiol supplementation was unable to reduce fatigue, limit inflammation, or restore performance in well-trained female athletes.

Topoisomerase IIIα is a type 1A topoisomerase that forms a complex with RMI1 and RMI2 called TRR in human cells. TRR plays an essential role in resolving DNA replication and recombination intermediates, often alongside the helicase BLM. While the TRR catalytic cycle is known to involve a protein-mediated single-stranded (ss)DNA gate, the detailed mechanism is not fully understood. Here, we probe the catalytic steps of TRR using optical tweezers and fluorescence microscopy. We demonstrate that TRR forms an open gate in ssDNA of 8.5 ± 3.8 nm, and directly visualize binding of a second ssDNA or double-stranded (ds)DNA molecule to the open TRR-ssDNA gate, followed by catenation in each case. Strikingly, dsDNA binding increases the gate size (by ~16%), while BLM alters the mechanical flexibility of the gate. These findings reveal an unexpected plasticity of the TRR-ssDNA gate size and suggest that TRR-mediated transfer of dsDNA may be more relevant in vivo than previously believed., (© 2022. The Author(s).)

Many genomic processes lead to the formation of underwound (negatively supercoiled) or overwound (positively supercoiled) DNA. These DNA topological changes regulate the interactions of DNA-binding proteins, including transcription factors, architectural proteins and topoisomerases. In order to advance our understanding of the structure and interactions of supercoiled DNA, we recently developed a single-molecule approach called Optical DNA Supercoiling (ODS). This method enables rapid generation of negatively supercoiled DNA (with between <5% and 70% lower helical twist than nonsupercoiled DNA) using a standard dual-trap optical tweezers instrument. ODS is advantageous as it allows for combined force spectroscopy, fluorescence imaging, and spatial control of the supercoiled substrate, which is difficult to achieve with most other approaches. Here, we describe how to generate negatively supercoiled DNA using dual-trap optical tweezers. To this end, we provide detailed instructions on the design and preparation of suitable DNA substrates, as well as a step-by-step guide for how to control and calibrate the supercoiling density produced., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Micronized copper (Cu) azole (MCA) wood preservative formulations include Cu in nano form, and relatively little is known about longer term effects of Cu leached from MCA into wetland ecosystems. We tested the hypothesis that changes in soil microbiomes within reconstructed freshwater wetlands will be associated with exposure to elevated Cu concentrations originating from immersed MCA-treated wood stakes. Eight replicate communities were assembled with Willamette Valley (OR, USA) flood plain soil and clonally propagated wetland plants within mesocosms. Inundated communities were equilibrated for 5 months before installation of MCA or control southern yellow pine stakes (n = 4 communities/experimental group). Soil samples were collected for 16S and internal transcribed spacer amplicon sequencing to quantify responses in prokaryotes and eukaryotes, respectively, at 15 time points, spanning two simulated seasonal dry downs, for up to 678 days. Physiochemical properties of water and soil were monitored at 20 and 12 time points respectively, over the same period. For both taxonomic groups of organisms, phylogenetic diversity increased and was positively correlated with elapsed days. Furthermore, there was significant divergence among eukaryotes during the second year based on experimental group. Although the composition of taxa underwent succession over time, there was significantly reduced relative abundance of sequence variants from Gomphonema diatoms and Scutellinia fungi in communities where MCA wood stakes were present compared with the controls. These focused microbiome shifts were positively correlated with surface water Cu and soil Cu concentrations, which were significantly elevated in treated communities. The reconstructed communities were effective systems for assessing potential impacts to wetland microbiomes after exposure to released copper. The results further inform postcommercialization risk assessments on MCA-treated wood. Environ Toxicol Chem 2021;40:3351-3368. Published 2021. This article is a U.S. Government work and is in the public domain in the USA., (Published 2021. This article is a U.S. Government work and is in the public domain in the USA.)

Micronized Cu (μ-Cu) is used as a wood preservative, replacing toxic chromated copper arsenate (CCA). Micronized Cu is malachite [Cu 2 CO 3 (OH) 2 ] that has been milled to micron/submicron particles, with many particle diameters less than 100 nm, mixed with biocides and then used to treat wood. In addition to concerns about the fate of the Cu from μ-Cu, there is interest in the fate of the nano-Cu (n-Cu) constituents. We examined movement of Cu from μ-Cu-treated wood after placing treated-wood stakes into model wetland ecosystems. Release of Cu into surface and subsurface water was monitored. Surface water Cu reached maximum levels 3 days after stake installation and remained elevated if the systems remained inundated. Subsurface water Cu levels were 10% of surface water levels at day 3 and increased gradually thereafter. Sequential filtering indicated that a large portion of the Cu in solution was associating with soluble organics, but there was no evidence for n-Cu in solution. After 4 months, Cu in thin-sections of treated wood and adjacent soil were characterized with micro X-ray absorption fine structure spectroscopy (μ-XAFS). Localization and speciation of Cu in the wood and adjacent soil using μ-XAFS clearly indicated that Cu concentrations decreased over time in the treated wood and increased in the adjacent soil. However, n-Cu from the treated wood was not found in the adjacent soil or plant roots. The results of this study indicate that Cu in the μ-Cu-treated wood dissolves and migrates into adjacent soil and waters primarily in ionic form (i.e., Cu 2+ ) and not as nano-sized Cu particles. A reduced form of Cu (Cu 2 S) was identified in deep soil proximal to the treated wood, indicating strong reducing conditions. The formation of the insoluble Cu 2 S effectively removes some portion of dissolved Cu from solution, reducing movement of Cu 2+ to the water column and diminishing exposure., (Published by Elsevier Ltd.)

The combination of DNA force spectroscopy and polarization microscopy of fluorescent DNA intercalator dyes can provide valuable insights into the structure of DNA under tension. These techniques have previously been used to characterize S-DNA-an elongated DNA conformation that forms when DNA overstretches at forces ≥ 65 pN. In this way, it was deduced that the base pairs of S-DNA are highly inclined, relative to those in relaxed (B-form) DNA. However, it is unclear whether and how topological constraints on the DNA may influence the base-pair inclinations under tension. Here, we apply polarization microscopy to investigate the impact of DNA pulling geometry, torsional constraint, and negative supercoiling on the orientations of intercalated dyes during overstretching. In contrast to earlier predictions, the pulling geometry (namely, whether the DNA molecule is stretched via opposite strands or the same strand) is found to have little influence. However, torsional constraint leads to a substantial reduction in intercalator tilting in overstretched DNA, particularly in AT-rich sequences. Surprisingly, the extent of intercalator tilting is similarly reduced when the DNA molecule is negatively supercoiled up to a critical supercoiling density (corresponding to ∼70% reduction in the linking number). We attribute these observations to the presence of P-DNA (an overwound DNA conformation). Our results suggest that intercalated DNA preferentially flanks regions of P-DNA rather than those of S-DNA and also substantiate previous suggestions that P-DNA forms predominantly in AT-rich sequences.

Topoisomerases are essential enzymes that regulate DNA topology. Type 1A family topoisomerases are found in nearly all living organisms and are unique in that they require single-stranded (ss)DNA for activity. These enzymes are vital for maintaining supercoiling homeostasis and resolving DNA entanglements generated during DNA replication and repair. While the catalytic cycle of Type 1A topoisomerases has been long-known to involve an enzyme-bridged ssDNA gate that allows strand passage, a deeper mechanistic understanding of these enzymes has only recently begun to emerge. This knowledge has been greatly enhanced through the combination of biochemical studies and increasingly sophisticated single-molecule assays based on magnetic tweezers, optical tweezers, atomic force microscopy and Förster resonance energy transfer. In this review, we discuss how single-molecule assays have advanced our understanding of the gate opening dynamics and strand-passage mechanisms of Type 1A topoisomerases, as well as the interplay of Type 1A topoisomerases with partner proteins, such as RecQ-family helicases. We also highlight how these assays have shed new light on the likely functional roles of Type 1A topoisomerases in vivo and discuss recent developments in single-molecule technologies that could be applied to further enhance our understanding of these essential enzymes., (© The Author(s) 2021. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Military service can include numerous adverse events. As such, resiliency has been considered as a means of potentially helping active-duty personnel face adversity and be better prepared for the demands of military service. However, research in military contexts has been hindered by use of disparate conceptualizations, definitions, and measures of resiliency. To provide some resolution to these inconsistencies, we use a comprehensive, theoretically based model of resiliency to explore how self-regulation processes contributed to Soldiers' negative affect and self-perceived effectiveness. We hypothesized that self-regulation (comprising distinct affective, behavioral, and cognitive processes) increments prediction of Soldiers' outcomes over and above trait-based resiliency protective factors. Using a sample of active-duty military personnel, cognitive self-regulation and affective self-regulation incremented the prediction of negative affect and self-perceived Soldier effectiveness, respectively, over and above trait-based protective factors. These results support the use of a comprehensive model and measure of resiliency, which may enable greater consistency across future research endeavors. As these results validated the links between self-regulation and post-adversity outcomes, this study provides a basis for developing new resiliency training programs. Additional implications for theory and continued research on resiliency in military contexts are discussed., Competing Interests: No potential conflict of interest was reported by the authors., (© 2021 Society for Military Psychology, Division 19 of the American Psychological Association.)

Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1-34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).., (© 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).)

A hallmark of aging is the progressive accumulation of cellular damage. Age-induced damage arises due to a decrease in organelle function along with a decline in protein quality control. Although somatic tissues deteriorate with age, the germline must maintain cellular homeostasis in order to ensure the production of healthy progeny. While germline quality control has been primarily studied in multicellular organisms, recent evidence suggests the existence of gametogenesis-specific quality control mechanisms in unicellular eukaryotes, highlighting the evolutionary conservation of meiotic events beyond chromosome morphogenesis. Notably, budding yeast eliminates age-induced damage during meiotic differentiation, employing novel organelle and protein quality control mechanisms to produce young and healthy gametes. Similarly, organelle and protein quality control is present in metazoan gametogenesis; however, whether and how these mechanisms contribute to cellular rejuvenation requires further investigation. Here, we summarize recent findings that describe organelle and protein quality control in budding yeast gametogenesis, examine similar quality control mechanisms in metazoan development, and identify research directions that will improve our understanding of meiotic cellular rejuvenation., (Copyright © 2020 Elsevier Inc. All rights reserved.)