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Winter climate is changing rapidly in northern latitudes, and these temperature events have effects on salmonid thermal biology. Stressors during winter egg incubation could reduce hatching success and physiological performance of fall-spawning fishes. Here we quantified the potential for ontogenic carryover effects from embryonic thermal stress in multiple wild and hatchery-origin populations of brook trout (Salvelinus fontinalis), a temperate ectotherm native to northeastern North America. Fertilized eggs from four populations were incubated over the winter in the laboratory in four differing thermal regimes: ambient stream-fed water, chronic warming (+2 °C), ambient with a mid-winter cold-shock, and short-term warming late during embryogenesis (to stimulate an early spring). We examined body size and upper thermal tolerance at the embryonic, fry (10 weeks post-hatch and 27-30 weeks post-hatch) and gravid adult (age 2+) life stages (overall N = 1482). In a separate experiment, we exposed developing embryos to acute seven-day heat stress events immediately following fertilization and at the eyed-egg stage, and then assessed upper thermal tolerance (CTmax) 37 weeks post-hatch. In all cases, fish were raised in common garden conditions after hatch (i.e., same temperatures). Our thermal treatments during incubation had effects that varied by life stage, with incubation temperature and life stage both affecting body size and thermal tolerance. Embryos incubated in warmer treatment groups had higher thermal tolerance; there was no effect of the mid-winter melt event on embryo CTmax. Ten weeks after hatch, fry from the ambient and cold-shock treatment groups had higher and less variable thermal tolerance than did the warmer treatment groups. At 27-30 post-hatch and beyond, differences in thermal tolerance among treatment groups were negligible. Collectively, our study suggests that brook trout only exhibit short-term carryover effects from thermal stressors during embryo incubation, with no lasting effects on phenotype beyond the first few months after hatch.
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Embrión no Mamífero , Trucha , Animales , Trucha/fisiología , Trucha/crecimiento & desarrollo , Trucha/embriología , Embrión no Mamífero/fisiología , Respuesta al Choque Térmico , Termotolerancia , Femenino , Desarrollo Embrionario , Tamaño CorporalRESUMEN
Background: Anterior cruciate ligament injury of the knee is common and leads to decreased activity and risk of secondary osteoarthritis of the knee. Management of patients with a non-acute anterior cruciate ligament injury can be non-surgical (rehabilitation) or surgical (reconstruction). However, insufficient evidence exists to guide treatment. Objective(s): To determine in patients with non-acute anterior cruciate ligament injury and symptoms of instability whether a strategy of surgical management (reconstruction) without prior rehabilitation was more clinically and cost-effective than non-surgical management (rehabilitation). Design: A pragmatic, multicentre, superiority, randomised controlled trial with two-arm parallel groups and 1:1 allocation. Due to the nature of the interventions, no blinding could be carried out. Setting: Twenty-nine NHS orthopaedic units in the United Kingdom. Participants: Participants with a symptomatic (instability) non-acute anterior cruciate ligament-injured knee. Interventions: Patients in the surgical management arm underwent surgical anterior cruciate ligament reconstruction as soon as possible and without any further rehabilitation. Patients in the rehabilitation arm attended physiotherapy sessions and only were listed for reconstructive surgery on continued instability following rehabilitation. Surgery following initial rehabilitation was an expected outcome for many patients and within protocol. Main outcome measures: The primary outcome was the Knee Injury and Osteoarthritis Outcome Score 4 at 18 months post randomisation. Secondary outcomes included return to sport/activity, intervention-related complications, patient satisfaction, expectations of activity, generic health quality of life, knee-specific quality of life and resource usage. Results: Three hundred and sixteen participants were recruited between February 2017 and April 2020 with 156 randomised to surgical management and 160 to rehabilitation. Forty-one per cent (nâ =â 65) of those allocated to rehabilitation underwent subsequent reconstruction within 18 months with 38% (nâ =â 61) completing rehabilitation and not undergoing surgery. Seventy-two per cent (nâ =â 113) of those allocated to surgery underwent reconstruction within 18 months. Follow-up at the primary outcome time point was 78% (nâ =â 248; surgical, nâ =â 128; rehabilitation, nâ =â 120). Both groups improved over time. Adjusted mean Knee Injury and Osteoarthritis Outcome Score 4 scores at 18 months had increased to 73.0 in the surgical arm and to 64.6 in the rehabilitation arm. The adjusted mean difference was 7.9 (95% confidence interval 2.5 to 13.2; pâ =â 0.005) in favour of surgical management. The per-protocol analyses supported the intention-to-treat results, with all treatment effects favouring surgical management at a level reaching statistical significance. There was a significant difference in Tegner Activity Score at 18 months. Sixty-eight per cent (nâ =â 65) of surgery patients did not reach their expected activity level compared to 73% (nâ =â 63) in the rehabilitation arm. There were no differences between groups in surgical complications (nâ =â 1 surgery, nâ =â 2 rehab) or clinical events (nâ =â 11 surgery, nâ =â 12 rehab). Of surgery patients, 82.9% were satisfied compared to 68.1% of rehabilitation patients. Health economic analysis found that surgical management led to improved health-related quality of life compared to non-surgical management (0.052 quality-adjusted life-years, pâ =â 0.177), but with higher NHS healthcare costs (£1107, pâ <â 0.001). The incremental cost-effectiveness ratio for the surgical management programme versus rehabilitation was £19,346 per quality-adjusted life-year gained. Using £20,000-30,000 per quality-adjusted life-year thresholds, surgical management is cost-effective in the UK setting with a probability of being the most cost-effective option at 51% and 72%, respectively. Limitations: Not all surgical patients underwent reconstruction, but this did not affect trial interpretation. The adherence to physiotherapy was patchy, but the trial was designed as pragmatic. Conclusions: Surgical management (reconstruction) for non-acute anterior cruciate ligament-injured patients was superior to non-surgical management (rehabilitation). Although physiotherapy can still provide benefit, later-presenting non-acute anterior cruciate ligament-injured patients benefit more from surgical reconstruction without delaying for a prior period of rehabilitation. Future work: Confirmatory studies and those to explore the influence of fidelity and compliance will be useful. Trial registration: This trial is registered as Current Controlled Trials ISRCTN10110685; ClinicalTrials.gov Identifier: NCT02980367. Funding: This award was funded by the National Institute of Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 14/140/63) and is published in full in Health Technology Assessment; Vol. 28, No. 27. See the NIHR Funding and Awards website for further award information.
The study aimed to find out whether it is better to offer surgical reconstruction or rehabilitation first to patients with a more long-standing injury of their anterior cruciate ligament in their knee. This injury causes physical giving way of the knee and/or sensations of it being wobbly (instability). The instability can affect daily activities, work, sport and can lead to arthritis. There are two main treatment options for this problem: non-surgical rehabilitation (prescribed exercises and advice from physiotherapists) or an operation by a surgeon to replace the damaged ligament (anterior cruciate ligament reconstruction). Although studies have highlighted the best option for a recently injured knee, the best management was not known for patients with a long-standing injury, perhaps occurring several months previously. Because the surgery is expensive to the NHS (around £100 million per year), it was also important to look at the costs involved. We carried out a study recruiting 316 non-acute anterior cruciate ligament-injured patients from 29 different hospitals and allocated each patient to either surgery or rehabilitation as their treatment option. We measured how well they did with special function and activity scores, patient satisfaction and costs of treatment. Patients in both groups improved substantially. It was expected that some patients in the rehabilitation group would want surgery if non-surgical management was unsuccessful. Forty-one per cent of patients who initially underwent rehabilitation subsequently elected to have reconstructive surgery. Overall, the patients allocated to the surgical reconstruction group had better results in terms of knee function and stability, activity level and satisfaction with treatment than patients allocated to the non-operative rehabilitation group. There were few problems or complications with either treatment option. Although the surgery was a more expensive treatment option, it was found to be cost-effective in the UK setting. The evidence can be discussed in shared decision-making with anterior cruciate ligament-injured patients. Both strategies of management led to improvement. Although a rehabilitation strategy can be beneficial, especially for recently injured patients, it is advised that later-presenting non-acute and more long-standing anterior cruciate ligament-injured patients undergo surgical reconstruction without necessarily delaying for a period of rehabilitation.
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Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Análisis Costo-Beneficio , Humanos , Masculino , Femenino , Lesiones del Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/rehabilitación , Adulto , Reino Unido , Reconstrucción del Ligamento Cruzado Anterior/rehabilitación , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Persona de Mediana Edad , Adulto Joven , Medicina Estatal , Inestabilidad de la Articulación/cirugía , Inestabilidad de la Articulación/rehabilitación , Adolescente , Evaluación de la Tecnología BiomédicaRESUMEN
Predicting soil water status remotely is appealing due to its low cost and large-scale application. During drought, plants can disconnect from the soil, causing disequilibrium between soil and plant water potentials at pre-dawn. The impact of this disequilibrium on plant drought response and recovery is not well understood, potentially complicating soil water status predictions from plant spectral reflectance. This study aimed to quantify drought-induced disequilibrium, evaluate plant responses and recovery, and determine the potential for predicting soil water status from plant spectral reflectance. Two species were tested: sweet corn (Zea mays), which disconnected from the soil during intense drought, and peanut (Arachis hypogaea), which did not. Sweet corn's hydraulic disconnection led to an extended 'hydrated' phase, but its recovery was slower than peanut's, which remained connected to the soil even at lower water potentials (-5 MPa). Leaf hyperspectral reflectance successfully predicted the soil water status of peanut consistently, but only until disequilibrium occurred in sweet corn. Our results reveal different hydraulic strategies for plants coping with extreme drought and provide the first example of using spectral reflectance to quantify rhizosphere water status, emphasizing the need for species-specific considerations in soil water status predictions from canopy reflectance.
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The appearance of senescent cells in age-related diseases has spurred the search for compounds that can target senescent cells in tissues, termed senolytics. However, a major caveat with current senolytic screens is the use of cell lines as targets where senescence is induced in vitro, which does not necessarily reflect the identity and function of pathogenic senescent cells in vivo. Here, we developed a new pipeline leveraging a fluorescent murine reporter that allows for isolation and quantification of p16Ink4a+ cells in diseased tissues. By high-throughput screening in vitro, precision-cut lung slice (PCLS) screening ex vivo, and phenotypic screening in vivo, we identified a HSP90 inhibitor, XL888, as a potent senolytic in tissue fibrosis. XL888 treatment eliminated pathogenic p16Ink4a+ fibroblasts in a murine model of lung fibrosis and reduced fibrotic burden. Finally, XL888 preferentially targeted p16INK4a-hi human lung fibroblasts isolated from patients with idiopathic pulmonary fibrosis (IPF), and reduced p16INK4a+ fibroblasts from IPF PCLS ex vivo. This study provides proof of concept for a platform where p16INK4a+ cells are directly isolated from diseased tissues to identify compounds with in vivo and ex vivo efficacy in mice and humans, respectively, and provides a senolytic screening platform for other age-related diseases.
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Senescencia Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Fibroblastos , Fibrosis Pulmonar Idiopática , Animales , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Ratones , Humanos , Fibroblastos/metabolismo , Fibroblastos/patología , Fibroblastos/efectos de los fármacos , Senescencia Celular/efectos de los fármacos , Fibrosis Pulmonar Idiopática/patología , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Fibrosis Pulmonar Idiopática/genética , Senoterapéuticos/farmacología , Masculino , Pulmón/patología , Pulmón/metabolismo , Femenino , Proteínas HSP90 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Proteínas HSP90 de Choque Térmico/genéticaRESUMEN
Among options for atmospheric CO2 removal, sequestering soil organic carbon (SOC) via improved grazing management is a rare opportunity because it is scalable across millions of globally grazed acres, low cost, and has high technical potential. Decades of scientific research on grazing and SOC has failed to form a cohesive understanding of how grazing management affects SOC stocks and their distribution between particulate (POM) and mineral-associated organic matter (MAOM)-characterized by different formation and stabilization pathways-across different climatic contexts. As we increasingly look to grazing management for SOC sequestration on grazinglands to bolster our climate change mitigation efforts, we need a clear and collective understanding of grazing management's impact on pathways of SOC change to inform on-the-ground management decisions. We set out to review the effects of grazing management on SOC through a unified plant ecophysiology and soil biogeochemistry conceptual framework, where elements such as productivity, input quality, soil mineral capacity, and climate variables such as aridity co-govern SOC accumulation and distribution into POM and MAOM. To maximize applicability to grazingland managers, we discuss how common management levers that drive overall grazing pattern, including timing, intensity, duration, and frequency can be used to optimize mechanistic pathways of SOC sequestration. We discuss important research needs and measurement challenges, and highlight how our conceptual framework can inform more robust research with greater applicability for maximizing the use of grazing management to sequester SOC.
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Carbono , Suelo , Suelo/química , Secuestro de Carbono , Cambio Climático , MineralesRESUMEN
Critical thermal maximum (CTmax ) is widely used to measure upper thermal tolerance in fish but is rarely examined in embryos. Upper thermal limits generally depend on an individual's thermal history, which molds plasticity. We examined how thermal acclimation affects thermal tolerance of brook trout (Salvelinus fontinalis) embryos using a novel method to assess CTmax in embryos incubated under three thermal regimes. Warm acclimation was associated with an increase in embryonic upper thermal tolerance. However, CTmax variability was markedly higher than is typical for juvenile or adult salmonids.
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Salmonidae , Trucha , Animales , Temperatura , Trucha/fisiología , Aclimatación , Tomografía Computarizada por Rayos XRESUMEN
Understanding processes that govern and sustain biological diversity is a central goal of community ecology. Unisexual complexes, where reproduction depends on sperm from males of one or more bisexual host species, are rare and the processes driving their diversity and structure remain poorly understood. Unisexual Ambystoma salamanders produce distinct biotypes ('genomotypes') depending on which bisexual species they 'steal' sperm from. This reproductive mode should generate distinct assemblages depending on the locally available bisexual host species. Yet, how availability and relative abundance of multiple bisexual hosts influences composition and diversity of natural unisexual assemblages at local or regional scales remains unknown. We hypothesize that host identity most directly drives local assemblage composition, with host variation associated with increased beta and gamma diversity within unisexuals. We collected genetic samples from Ambystoma salamanders across Pelee Island, Ontario, Canada (2015-2022). Two host species were identified (A. texanum and A. laterale) with nine sites having a single host and one site having both. Unisexual assemblages were grouped into four clusters by similarity, with host identity being a key determinant. Gamma diversity increased as a result of distinct host-specific assemblages forming at different sites on the island (i.e., high beta diversity). Assemblage composition, but not diversity, was correlated with relative host abundance, which may reflect matching niche requirements between host and unisexual forms they produce. Our results demonstrate that diversity and structure of unisexual assemblages are clearly shaped by their host(s) and such systems may serve as models for studying how biotic interactions shape ecological communities.
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Semen , Urodelos , Masculino , Animales , Ambystoma , Biodiversidad , PloidiasRESUMEN
Importance: Ischemic heart disease remains the leading cause of mortality following hip and knee arthroplasty. Due to its antiplatelet and cardioprotective properties, aspirin has been proposed as an agent that could reduce mortality when used as venous thromboembolism (VTE) prophylaxis following these procedures. Objective: To compare aspirin with enoxaparin in reducing 90-day mortality for patients undergoing hip or knee arthroplasty procedures. Design, Setting, and Participants: This study was a planned secondary analysis of the CRISTAL cluster randomized, crossover, registry-nested trial performed across 31 participating hospitals in Australia between April 20, 2019, and December 18, 2020. The aim of the CRISTAL trial was to determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE following hip or knee arthroplasty. The primary study restricted the analysis to patients undergoing total hip or knee arthroplasty for a diagnosis of osteoarthritis only. This study includes all adult patients (aged ≥18 years) undergoing any hip or knee arthroplasty procedure at participating sites during the course of the trial. Data were analyzed from June 1 to September 6, 2021. Interventions: Hospitals were randomized to administer all patients oral aspirin (100 mg daily) or subcutaneous enoxaparin (40 mg daily) for 35 days after hip arthroplasty and 14 days after knee arthroplasty procedures. Main Outcomes and Measures: The primary outcome was mortality within 90 days. The between-group difference in mortality was estimated using cluster summary methods. Results: A total of 23â¯458 patients from 31 hospitals were included, with 14â¯156 patients allocated to aspirin (median [IQR] age, 69 [62-77] years; 7984 [56.4%] female) and 9302 patients allocated to enoxaparin (median [IQR] age, 70 [62-77] years; 5277 [56.7%] female). The mortality rate within 90 days of surgery was 1.67% in the aspirin group and 1.53% in the enoxaparin group (estimated difference, 0.04%; 95% CI, -0.05%-0.42%). For the subgroup of 21â¯148 patients with a nonfracture diagnosis, the mortality rate was 0.49% in the aspirin group and 0.41% in the enoxaparin group (estimated difference, 0.05%; 95% CI, -0.67% to 0.76%). Conclusions and Relevance: In this secondary analysis of a cluster randomized trial comparing aspirin with enoxaparin following hip or knee arthroplasty, there was no significant between-group difference in mortality within 90 days when either drug was used for VTE prophylaxis. Trial Registration: http://anzctr.org.au Identifier: ACTRN12618001879257.
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Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Tromboembolia Venosa , Adulto , Humanos , Femenino , Adolescente , Anciano , Masculino , Enoxaparina/uso terapéutico , Enoxaparina/efectos adversos , Aspirina/uso terapéutico , Tromboembolia Venosa/tratamiento farmacológico , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Cadera/efectos adversosRESUMEN
Kinship-based methods of population assessment such as close-kin mark-recapture require accurate and efficient genotyping methods capable of resolving complex relationships among kin. Inference of such relationships can be difficult using biallelic loci due to the large number of markers required to obtain the necessary power. Sequencing-based microsatellite panels offer an efficient alternative, combining high polymorphism with efficient next-generation methods. Here we construct, optimize, and test one such panel for lake trout (Salvelinus namaycush) using a combination of previously-published loci adapted for sequencing and de novo loci mined from a genome assembly. We performed three rounds of primer optimization, yielding a final panel of 131 loci, followed by testing with two different levels of PCR multiplexing (all primers in one or two groups) and two different reaction volumes (5 and 10 µL). Our results showed that the use of the largest multiplex and smallest reaction volume did not substantially change results, allowing significant cost and time savings. To test panel accuracy, we used both a set of 153 known-origin samples from origins of management interest and a series of hatchery crosses representing nine families with parent-offspring, half-sibling, and largely-unrelated pairs. Our results indicate that sequencing-based microsatellite panels can efficiently and accurately provide the information required for a population genetics analyses including population assignment, calculation of between-population F ST, and kinship-based population estimation techniques. Such techniques are seeing increasing applications for a wide range of taxa; our findings should provide insight and guidance for the development of the necessary molecular resources.
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Critical thermal maximum (CTmax) is widely used for measuring thermal tolerance but the strong effect of acclimation on CTmax is a likely source of variation within and among studies/species that makes comparisons more difficult. There have been surprisingly few studies focused on quantifying how quickly acclimation occurs or that combine temperature and duration effects. We studied the effects of absolute temperature difference and duration of acclimation on CTmax of brook trout (Salvelinus fontinalis), a well-studied species in the thermal biology literature, under laboratory conditions to determine how each of the two factors and their combined effects influence critical thermal maximum. Using an ecologically-relevant range of temperatures and testing CTmax multiple times between one and 30 days, we found that both temperature and duration of acclimation had strong effects on CTmax. As predicted, fish that were exposed to warmer temperatures longer had increased CTmax, but full acclimation (i.e., a plateau in CTmax) did not occur by day 30. Therefore, our study provides useful context for thermal biologists by demonstrating that the CTmax of fish can continue to acclimate to a new temperature for at least 30 days. We recommend that this be considered in future studies measuring thermal tolerance that intend to have their organisms fully acclimated to a given temperature. Our results also support using detailed thermal acclimation information to reduce uncertainty caused by local or seasonal acclimation effects and to improve the use of CTmax data for fundamental research and conservation planning.
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Aclimatación , Peces , Animales , TemperaturaRESUMEN
Hypodiploid acute lymphoblastic leukemia (ALL) is an aggressive blood cancer with a poor prognosis despite intensive chemotherapy or stem cell transplant. Children and adolescents with positive end-of-induction minimal residual disease have an overall survival lower than 30%. However, data regarding therapeutic alternatives for this disease is nearly nonexistent, emphasizing the critical need for new or adjunctive therapies that can improve outcomes. We previously reported on the therapeutic efficacy of venetoclax (ABT-199) in hypodiploid B-lineage ALL but with limitations as monotherapy. In this study, we set out to identify drugs enhancing the anti-leukemic effect of venetoclax in hypodiploid ALL. Using a highthroughput drug screen, we identified dinaciclib, a cyclin-dependent kinase inhibitor that worked synergistically with venetoclax to induce cell death in hypodiploid cell lines. This combination eradicated leukemic blasts within hypodiploid ALL patient-derived xenografts mice with low off-target toxicity. Our findings suggest that dual inhibition of BCL-2 (venetoclax) and CDK9/MCL-1 (dinaciclib) is a promising therapeutic approach in hypodiploid ALL, warranting further investigation to inform clinical trials in this high-risk patient population.
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Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Animales , Ratones , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Línea Celular Tumoral , Apoptosis , Proteínas Proto-Oncogénicas c-bcl-2 , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Antineoplásicos/farmacologíaRESUMEN
Cases of feline tuberculosis (TB) can be challenging to diagnose. Currently, this is achieved through a combination of mycobacterial culture, polymerase chain reaction (PCR), or interferon-gamma release assay (IGRA); however, these each have limitations. There is limited data regarding the use of humoral immunodiagnostics for TB in cats. Therefore, we sought to develop an enzyme-linked immunosorbent assay (ELISA) to further facilitate the diagnosis of feline TB. A comparative PPD (purified protein derivative) antibody ELISA was optimised for use on serum and plasma, and was tested against samples from 14 cats with culture-confirmed TB and 24 uninfected controls. Selection of an appropriate positive cut-off value based on receiver-operator characteristic curve analysis gave test sensitivity of 64.3 % and specificity of 100 %. When tested on further samples from cats with strongly suspected mycobacteriosis, 32.9 % (23/70) were antibody positive. Notably, positive results were recorded in cats that failed to respond to the IGRA, and in one PCR and IGRA negative cat. No positive responses were identified in cats with non-tuberculous mycobacterial infections, or with non-mycobacterial diseases (n = 12). Therefore, antibody-based diagnostics may be useful adjunctive tests for cases of TB missed by the IGRA, helping protect both feline and, in turn, human health.
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Enfermedades de los Gatos , Mycobacterium tuberculosis , Tuberculosis , Gatos , Animales , Humanos , Interferón gamma , Tuberculosis/diagnóstico , Tuberculosis/veterinaria , Ensayos de Liberación de Interferón gamma/métodos , Ensayos de Liberación de Interferón gamma/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Ensayo de Inmunoadsorción Enzimática/métodos , Sensibilidad y Especificidad , Enfermedades de los Gatos/diagnósticoRESUMEN
BACKGROUND: Both medial knee osteoarthritis and associated varus alignment have been proposed to alter knee joint loading and consequently overloading the medial compartment. Individuals with knee osteoarthritis and varus deformity are candidates for coronal plane corrective surgery, high tibial osteotomy. This study evaluated knee loading and contact location for a control group, a pre-surgery cohort and the same cohort 12 months post-surgery using a musculoskeletal modelling approach. METHODS: Joint kinematics during gait were measured in 30 knee osteoarthritis patients, before and after high tibial osteotomy, and 28 healthy adults. Using a musculoskeletal model that incorporated patient-specific mechanical tibial femoral angle, the resulting muscle, ligament, and contact forces were calculated and the medial - lateral condyle load distribution was analysed. FINDINGS: Surgery changed medial compartment contact force throughout stance relative to pre-surgery. This reduction in medial compartment contact force pre- vs post-HTO is observed despite a significant increase in post-surgery walking speed compared to pre-HTO, where increased speed is typically associated with increased joint loading. INTERPRETATION: This study has estimated the effects of high tibial osteotomy on knee loading using a generic model that incorporates a detailed knee model to better understand tibiofemoral contact loading. The findings support the aim of surgery to unload the medial knee compartment and lateralise joint contact forces.
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Osteoartritis de la Rodilla , Adulto , Humanos , Osteoartritis de la Rodilla/cirugía , Articulación de la Rodilla/cirugía , Articulación de la Rodilla/fisiología , Tibia/cirugía , Fémur , Fenómenos Biomecánicos/fisiología , Osteotomía/métodosRESUMEN
This article reconstructs how Arab doctors, medical missionaries, British counterinsurgents, and Palestinian rebels negotiated and contested the legitimate role of medical workers and healthcare in times of colonial conflict. Drawing insight from a medical anthropological literature which challenges the notion of medical neutrality as normative, and setting mandate Palestine alongside other case studies of medicine in times of conflict from the interwar Middle East and North Africa, this article argues that while healthcare and medical authority could be put to work to support the colonial status quo, they could serve other, more radical ends too. To highlight the complexity of the political positioning of medical workers and healthcare, this article focuses on the town of Hebron during the great revolt which rocked the foundations of British rule in Palestine between 1936 and 1939, and relies on a range of colonial and missionary archival sources. The first part of the article uses the case study of an Egyptian medical doctor who took up political office in the town in moments of crisis to show how medical authority could be consciously transmuted into a force to uphold a besieged political order. The second part draws on the diary of a British mission doctor to reconstruct his efforts to assert medical neutrality during the great revolt, and-more strikingly still-how Palestinian insurgents participated actively in this attempt to transplant international legal protections to Hebron. The final part traces the incorporation of healthcare into the strategies of both British counterinsurgents and Palestinian rebels, with the British policy of collective punishment indirectly but appreciably degrading access to healthcare for Palestinians, and Palestinian counterstate ambitions extending to the establishment of insurgent medical services in the hills.
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Árabes , Condiciones Sociales , Humanos , Historia del Siglo XX , Medio OrienteRESUMEN
Conservation and management professionals often work across jurisdictional boundaries to identify broad ecological patterns. These collaborations help to protect populations whose distributions span political borders. One common limitation to multijurisdictional collaboration is consistency in data recording and reporting. This limitation can impact genetic research, which relies on data about specific markers in an organism's genome. Incomplete overlap of markers between separate studies can prevent direct comparisons of results. Standardized marker panels can reduce the impact of this issue and provide a common starting place for new research. Genotyping-in-thousands (GTSeq) is one approach used to create standardized marker panels for nonmodel organisms. Here, we describe the development, optimization, and early assessments of a new GTSeq panel for use with walleye (Sander vitreus) from the Great Lakes region of North America. High genome-coverage sequencing conducted using RAD capture provided genotypes for thousands of single nucleotide polymorphisms (SNPs). From these markers, SNP and microhaplotype markers were chosen, which were informative for genetic stock identification (GSI) and kinship analysis. The final GTSeq panel contained 500 markers, including 197 microhaplotypes and 303 SNPs. Leave-one-out GSI simulations indicated that GSI accuracy should be greater than 80% in most jurisdictions. The false-positive rates of parent-offspring and full-sibling kinship identification were found to be low. Finally, genotypes could be consistently scored among separate sequencing runs >94% of the time. Results indicate that the GTSeq panel that we developed should perform well for multijurisdictional walleye research throughout the Great Lakes region.
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Introduction British Orthopaedic Association Standards for Trauma (BOAST) guidelines state that a radiograph of the wrist at the time of removal of immobilisation is not required in conservatively managed distal radius fracture (DRF) patients unless there is clinical cause for concern. The aim of this pilot audit was to investigate local compliance with these guidelines. Materials and methods The first cycle of a retrospective audit was performed on conservatively managed DRF patients presenting between August and October 2021. An intervention was introduced in the form of education to highlight current guidelines. A second cycle was then performed prospectively on patients presenting between February and April 2022. Data was analysed to assess whether radiographs were taken at the time of cast removal, if the indication for the radiograph was documented and whether it affected the management plan. Results In the first cycle, 20 of 46 patients (43.5%) had repeat radiographs at the time of cast removal compared to 12 of 41 patients (29.3%) in the second cycle (p=0.170). None of the first-cycle patients had any documentation on the indication for radiograph at the time of cast removal and none of the radiographs altered the management plan. In the second cycle documentation on the indication for the radiograph was present for seven of the 12 radiographs and two altered the management plan. Conclusion Through education on adherence to national guidelines, the number of radiographs in patients with conservatively managed DRFs was reduced.
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Chromosome instability (CIN) is an early step in carcinogenesis that promotes tumor cell progression and resistance to therapy. Using plasmids integrated adjacent to telomeres, we have previously demonstrated that the sensitivity of subtelomeric regions to DNA double-strand breaks (DSBs) contributes to telomere loss and CIN in cancer. A high-throughput screen was created to identify compounds that affect telomere loss due to subtelomeric DSBs introduced by I-SceI endonuclease, as detected by cells expressing green fluorescent protein (GFP). A screen of a library of 1832 biologically-active compounds identified a variety of compounds that increase or decrease the number of GFP-positive cells following activation of I-SceI. A curated screen done in triplicate at various concentrations found that inhibition of classical nonhomologous end joining (C-NHEJ) increased DSB-induced telomere loss, demonstrating that C-NHEJ is functional in subtelomeric regions. Compounds that decreased DSB-induced telomere loss included inhibitors of mTOR, p38 and tankyrase, consistent with our earlier hypothesis that the sensitivity of subtelomeric regions to DSBs is a result of inappropriate resection during repair. Although this assay was also designed to identify compounds that selectively target cells experiencing telomere loss and/or chromosome instability, no compounds of this type were identified in the current screen.
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AbstractThe rise in temperature associated with climate change may threaten the persistence of stenothermal organisms with limited capacities for beneficial thermal acclimation. We investigated the capacity for within-generation and transgenerational thermal responses in brook trout (Salvelinus fontinalis), a cold-adapted salmonid. Adult fish were acclimated to temperatures within (10°C) and above (21°C) their thermal optimum for 6 mo before spawning, then mated in a full factorial breeding design to produce offspring from cold- and warm-acclimated parents and bidirectional crosses between parents from both temperature treatments. Offspring from families were subdivided and reared at two acclimation temperatures representing their current (15°C) and anticipated future (19°C) habitat temperatures. Offspring thermal physiology was measured as the rate of oxygen consumption (Mo2) during an acute change in temperature (increase of 2°C h-1) to observe their Mo2-temperature relationship. We recorded resting Mo2, peak (highest achieved, thermally induced) Mo2, and critical thermal maximum (CTM) as performance metrics. Although limited, within-generation plasticity was greater than transgenerational plasticity, with offspring warm acclimation elevating CTM by 0.5°C but slightly lowering peak thermally induced Mo2. Transgenerational plasticity was evident as a slightly elevated resting Mo2 and a shift of the Mo2-temperature relationship to higher rates overall in offspring from warm-acclimated parents. Furthermore, offspring whose parents were warm acclimated were in worse condition than those whose parents were cold acclimated. Both parents contributed to offspring thermal responses; however, the paternal effect was stronger. Despite the existence of within-generation and transgenerational plasticity in brook trout, it is unlikely that these will be sufficient for coping with long-term changes to environmental temperatures.
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Salmonidae , Aclimatación/fisiología , Animales , Consumo de Oxígeno , Salmonidae/genética , Temperatura , Trucha/genéticaRESUMEN
BACKGROUND: Anterior cruciate ligament (ACL) rupture is a common debilitating injury that can cause instability of the knee. We aimed to investigate the best management strategy between reconstructive surgery and non-surgical treatment for patients with a non-acute ACL injury and persistent symptoms of instability. METHODS: We did a pragmatic, multicentre, superiority, randomised controlled trial in 29 secondary care National Health Service orthopaedic units in the UK. Patients with symptomatic knee problems (instability) consistent with an ACL injury were eligible. We excluded patients with meniscal pathology with characteristics that indicate immediate surgery. Patients were randomly assigned (1:1) by computer to either surgery (reconstruction) or rehabilitation (physiotherapy but with subsequent reconstruction permitted if instability persisted after treatment), stratified by site and baseline Knee Injury and Osteoarthritis Outcome Score-4 domain version (KOOS4). This management design represented normal practice. The primary outcome was KOOS4 at 18 months after randomisation. The principal analyses were intention-to-treat based, with KOOS4 results analysed using linear regression. This trial is registered with ISRCTN, ISRCTN10110685, and ClinicalTrials.gov, NCT02980367. FINDINGS: Between Feb 1, 2017, and April 12, 2020, we recruited 316 patients. 156 (49%) participants were randomly assigned to the surgical reconstruction group and 160 (51%) to the rehabilitation group. Mean KOOS4 at 18 months was 73·0 (SD 18·3) in the surgical group and 64·6 (21·6) in the rehabilitation group. The adjusted mean difference was 7·9 (95% CI 2·5-13·2; p=0·0053) in favour of surgical management. 65 (41%) of 160 patients allocated to rehabilitation underwent subsequent surgery according to protocol within 18 months. 43 (28%) of 156 patients allocated to surgery did not receive their allocated treatment. We found no differences between groups in the proportion of intervention-related complications. INTERPRETATION: Surgical reconstruction as a management strategy for patients with non-acute ACL injury with persistent symptoms of instability was clinically superior and more cost-effective in comparison with rehabilitation management. FUNDING: The UK National Institute for Health Research Health Technology Assessment Programme.
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Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Traumatismos de la Rodilla , Lesiones del Ligamento Cruzado Anterior/diagnóstico , Lesiones del Ligamento Cruzado Anterior/etiología , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/efectos adversos , Reconstrucción del Ligamento Cruzado Anterior/métodos , Humanos , Traumatismos de la Rodilla/etiología , Traumatismos de la Rodilla/rehabilitación , Traumatismos de la Rodilla/cirugía , Articulación de la Rodilla/cirugía , Medicina Estatal , Resultado del TratamientoRESUMEN
Importance: There remains a lack of randomized trials investigating aspirin monotherapy for symptomatic venous thromboembolism (VTE) prophylaxis following total hip arthroplasty (THA) or total knee arthroplasty (TKA). Objective: To determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE after THA or TKA. Design, Setting, and Participants: Cluster-randomized, crossover, registry-nested trial across 31 hospitals in Australia. Clusters were hospitals performing greater than 250 THA or TKA procedures annually. Patients (aged ≥18 years) undergoing hip or knee arthroplasty procedures were enrolled at each hospital. Patients receiving preoperative anticoagulation or who had a medical contraindication to either study drug were excluded. A total of 9711 eligible patients were enrolled (5675 in the aspirin group and 4036 in the enoxaparin group) between April 20, 2019, and December 18, 2020. Final follow-up occurred on August 14, 2021. Interventions: Hospitals were randomized to administer aspirin (100 mg/d) or enoxaparin (40 mg/d) for 35 days after THA and for 14 days after TKA. Crossover occurred after the patient enrollment target had been met for the first group. All 31 hospitals were initially randomized and 16 crossed over prior to trial cessation. Main Outcomes and Measures: The primary outcome was symptomatic VTE within 90 days, including pulmonary embolism and deep venous thrombosis (DVT) (above or below the knee). The noninferiority margin was 1%. Six secondary outcomes are reported, including death and major bleeding within 90 days. Analyses were performed by randomization group. Results: Enrollment was stopped after an interim analysis determined the stopping rule was met, with 9711 patients (median age, 68 years; 56.8% female) of the prespecified 15â¯562 enrolled (62%). Of these, 9203 (95%) completed the trial. Within 90 days of surgery, symptomatic VTE occurred in 256 patients, including pulmonary embolism (79 cases), above-knee DVT (18 cases), and below-knee DVT (174 cases). The symptomatic VTE rate in the aspirin group was 3.45% and in the enoxaparin group was 1.82% (estimated difference, 1.97%; 95% CI, 0.54%-3.41%). This failed to meet the criterion for noninferiority for aspirin and was significantly superior for enoxaparin (P = .007). Of 6 secondary outcomes, none were significantly better in the enoxaparin group compared with the aspirin group. Conclusions and Relevance: Among patients undergoing hip or knee arthroplasty for osteoarthritis, aspirin compared with enoxaparin resulted in a significantly higher rate of symptomatic VTE within 90 days, defined as below- or above-knee DVT or pulmonary embolism. These findings may be informed by a cost-effectiveness analysis. Trial Registration: ANZCTR Identifier: ACTRN12618001879257.