We systematically collected an integrated atlas of 273,923 single-cell transcriptomes from the muscles of mice divided into young, old, and geriatric age groups (5, 20, and 26 months old), monitored over six time points post-myotoxin injury. Eight cell types, including subsets of T cells, NK cells, and macrophages, showed differing response kinetics across age groups, with some showing accelerated and others slower dynamics. Through the application of pseudotime analysis, we found the characteristic myogenic cell states and trajectories of old and geriatric ages. Cellular senescence was assessed by employing experimentally validated and compiled gene lists to explore age discrepancies. Aged muscles exhibited a discernible increase in senescent-like subpopulations, notably among their self-renewing muscle stem cells. Across the lifespan of the mouse, this resource details the diverse, altered cellular states that underlie the decline of skeletal muscle regenerative capacity.
Regeneration of skeletal muscle necessitates the synchronized participation of both myogenic and non-myogenic cells, with a meticulously planned spatial and temporal arrangement. The regenerative capacity of skeletal muscle progressively weakens with the aging process, a consequence of alterations in myogenic stem/progenitor cell states and functions, the influence of non-myogenic cell types, and systemic changes, all of which become more pronounced with advancing age. Elaidoic acid A complete, network-based analysis of the cellular and external changes influencing muscle stem/progenitor cell participation in muscle regeneration across the lifespan has not yet been definitively established. To generate a thorough atlas of regenerative muscle cell states throughout a mouse's lifetime, we have collected 273,923 single-cell transcriptomes from the hindlimb muscles of young, old, and geriatric (4-7, 20, and 26 months-old, respectively) mice at six precisely timed intervals after inducing myotoxin injury. Our research unveiled 29 muscle cell types, 8 demonstrating altered abundance across age cohorts. These included T cells, NK cells, and varied macrophage populations, proposing that the age-dependent decline in muscle repair capacity might stem from a temporal misalignment within the inflammatory response's progression. Plant genetic engineering Investigating myogenic cell populations throughout the regeneration period, our pseudotime analysis disclosed age-dependent trajectories of myogenic stem/progenitor cells in old and geriatric muscles. Cellular senescence's significant role in limiting cellular function in aging tissues led to the development of a collection of bioinformatics tools, intended for identifying senescence in single-cell data and assessing their performance in pinpointing senescence in key myogenic stages. Assessing the relationship between single-cell senescence scores and the co-expression pattern of hallmark senescence genes reveals
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Using a model of muscle foreign body response (FBR) fibrosis, we experimentally constructed a gene list that successfully identified senescent-like myogenic cells across different mouse ages, injury points, and cell cycle phases with high accuracy (receiver-operator curve AUC = 0.82-0.86), demonstrating performance equivalent to curated lists. This scoring approach, additionally, delineated transient senescence subtypes within the myogenic stem/progenitor cell developmental pathway, showing a correlation with arrested MuSC self-renewal at all ages in mice. Exploring aging mouse skeletal muscle, this new resource comprehensively details the evolving cellular states and interaction networks supporting skeletal muscle regeneration throughout a mouse's life cycle.
The process of skeletal muscle regeneration is driven by the coordinated actions of myogenic and non-myogenic cells, demonstrating a delicate balance in spatial and temporal organization. Myogenic stem/progenitor cell states and functions, non-myogenic cell contributions, and systemic alterations accumulate with age, causing a decrease in the regenerative capacity of skeletal muscle. A detailed network analysis of cell-intrinsic and -extrinsic changes affecting muscle stem/progenitor cell involvement in muscle regeneration across the lifespan is presently lacking. An atlas of regenerative muscle cell states across the mouse lifespan was created using 273,923 single-cell transcriptomes from hindlimb muscles of young, aged, and geriatric mice (4-7, 20, and 26 months old, respectively), collected at six time points following myotoxin injury, with samples taken at close intervals. Twenty-nine muscle-resident cell types were identified; eight displayed altered abundance patterns in different age groups, including T cells, NK cells, and multiple macrophage subtypes. This may indicate that age-related declines in muscle repair are driven by a miscoordination of the inflammatory response. A pseudotime analysis of myogenic cells throughout the regeneration process showed distinct age-related trajectories for myogenic stem/progenitor cells in both old and geriatric muscle tissue. Senescence's critical role in restricting cell functions within aging tissues drove the creation of a series of bioinformatics tools. These tools were specifically designed to discover senescence in single-cell datasets and evaluate their performance in identifying senescence markers across crucial myogenic stages. By analyzing the relationship between single-cell senescence scores and the co-expression of hallmark senescence genes Cdkn2a and Cdkn1a, we determined that an empirically derived gene list from a muscle foreign body response (FBR) fibrosis model effectively (AUC = 0.82-0.86 on receiver-operator curves) identified senescent-like myogenic cells across various mouse ages, injury time points, and cell cycle stages, replicating the precision of curated gene lists. Subsequently, this scoring method isolated transitory senescence subgroups of myogenic stem/progenitor cells that are related to stalled MuSC self-renewal states in mice of all ages. A detailed analysis of aging mouse skeletal muscle provides a complete picture of the shifting cellular states and interaction networks crucial for skeletal muscle regeneration during the entire lifespan of the mouse.
Subsequent to cerebellar tumor resection in pediatric patients, cerebellar mutism syndrome is observed in approximately 25% of cases. The cerebellar outflow pathway, comprised of the cerebellar deep nuclei and superior cerebellar peduncles, has been shown by our group to be associated with a greater likelihood of CMS occurrence when damaged. To determine the generalizability of these findings, we analyzed an independent data set. We undertook an observational study of 56 pediatric patients that underwent cerebellar tumor removal to assess if there was a link between the location of the lesion and the manifestation of CMS. We theorized that individuals who developed CMS following surgery (CMS+) would show lesions that intersect significantly more with 1) the cerebellar outflow pathway, and 2) a previously mapped lesion-symptom correlation for CMS. The analyses were conducted, in keeping with pre-registered hypotheses and analytic methods, as specified at (https://osf.io/r8yjv/). Microbial ecotoxicology Our research confirmed the existence of supporting evidence for both hypotheses. When compared to CMS- patients, CMS+ patients (n=10) displayed lesions with an increased overlap along the cerebellar outflow pathway (Cohen's d = .73, p = .05), and on the CMS lesion-symptom map (Cohen's d = 11, p = .004). The results confirm the connection between lesion position and the risk of CMS occurrence, proving applicability across multiple study groups. Pediatric cerebellar tumor surgery might benefit from the guidance offered by these findings, leading to an optimal approach.
Health systems intended to enhance hypertension and cardiovascular disease care have not been subjected to many rigorous evaluations in sub-Saharan Africa. Evaluation of the Ghana Heart Initiative (GHI), a multi-faceted supply-side program to improve cardiovascular health in Ghana, will consider its reach, effectiveness, acceptance, fidelity of implementation, associated costs, and long-term sustainability. Employing a mixed-methods, multi-faceted approach, this study investigates the impact of the GHI within 42 participating health facilities. Within the Greater Accra Region, a comparison was conducted on primary, secondary, and tertiary health facilities, while 56 control facilities from the Central and Western Regions served as a benchmark. The evaluation design is structured by the RE-AIM framework, incorporating the WHO health systems building blocks and the Institute of Medicine's six dimensions of health care quality: safe, effective, patient-centered, timely, efficient, and equitable. Evaluation tools include: (i) a health facility survey, (ii) a healthcare provider survey concerning their knowledge, attitudes, and practices on hypertension and cardiovascular disease management, (iii) a patient exit survey, (iv) a review of outpatient and inpatient medical records, and (v) qualitative interviews with patients and various health system stakeholders to determine the barriers and facilitators to the Global Health Initiative implementation. The study's approach involves primary data collection, supplemented by secondary routine data from the District Health Information Management System. This data is used to conduct an interrupted time series analysis, evaluating monthly counts of hypertension and cardiovascular disease-specific indicators as the outcomes. Performance of health service delivery indicators, including inputs, processes, and outcomes of care (such as hypertension screening, newly diagnosed hypertension, guideline-directed medical therapy prescriptions, and patient satisfaction/acceptability), will be compared between intervention and control facilities to assess primary outcomes. Subsequently, an economic evaluation and budget impact assessment is intended to support the nationwide growth of the GHI. Through this study, policy-relevant data will be collected about the GHI's distribution, efficiency, faithfulness of implementation, reception, and longevity. The study will also examine cost and budget impact analysis, informing national-scale expansion of the GHI to different parts of Ghana and offering valuable lessons for similar contexts in low- and middle-income countries.