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1.
PLoS One ; 19(6): e0306171, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38924067

RESUMO

This study aims to establish the validity and reliability of the prone Yo-YoIRL1 in elite female rugby league players (part one) and determine the anthropometric and physical characteristics contributing to 15m prone Yo-YoIRL1 performance (part two). Part one, 21 subjects completed one Yo-YoIRL1, one 20m and two 15m prone Yo-YoIRL1 tests over four sessions, with 7-14 days in-between. Part two, ten subjects completed a testing battery, including body mass, height, dual-energy x-ray absorptiometry, isometric mid-thigh pull, isometric bench-press, 10m and 20m sprints and an incremental treadmill test ([Formula: see text]). The 15m prone YoYoIRL1 demonstrated poor reliability with a typical error of 68m (21%) and a smallest worthwhile change of 54m (9%). Validity analysis found the prone versions of the YoYoIRL1 were not sensitive measures of intermittent running performance. Both prone YoYoIRL1 test distances demonstrated large mean bias (76% and -37% respectively) and typical error of the estimate (19% and 21%, respectively) in comparison to the YoYoIRL1. Body mass (r = -0.89), lean mass (r = -0.64), body fat % (r = -0.68), [Formula: see text] (l∙min-1) (r = -0.64), IMTP (r = -0.69), IBP (r = -0.15), 10m (r = -0.77) and 20m (r = -0.72) momentum displayed large negative relationships with 15m prone Yo-YoIRL1 performance. Due to the poor validity of the 20m prone YoYoIRL1, the poor validity and reliability of the 15m prone YoYoIRL1, and the anthropometric and physical characteristics which negatively impact performance, practitioners should reconsider the use of the prone YoYoIRL1 test to monitor high intensity intermittent running performance.


Assuntos
Desempenho Atlético , Teste de Esforço , Futebol Americano , Humanos , Feminino , Teste de Esforço/métodos , Reprodutibilidade dos Testes , Adulto Jovem , Adulto , Futebol Americano/fisiologia , Desempenho Atlético/fisiologia , Corrida/fisiologia , Atletas , Absorciometria de Fóton , Rugby
2.
PLoS One ; 19(2): e0297897, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38363784

RESUMO

Fusobacterium nucleatum (Fn) and enterotoxigenic Bacteroides fragilis (ETBF) are two pathobionts consistently enriched in the gut microbiomes of patients with colorectal cancer (CRC) compared to healthy counterparts and frequently observed for their direct association within tumors. Although several molecular mechanisms have been identified that directly link these organisms to features of CRC in specific cell types, their specific effects on the epithelium and local immune compartment are not well-understood. To fill this gap, we leveraged single-cell RNA sequencing (scRNA-seq) on wildtype mice and mouse model of CRC. We find that Fn and ETBF exacerbate cancer-like transcriptional phenotypes in transit-amplifying and mature enterocytes in a mouse model of CRC. We also observed increased T cells in the pathobiont-exposed mice, but these pathobiont-specific differences observed in wildtype mice were abrogated in the mouse model of CRC. Although there are similarities in the responses provoked by each organism, we find pathobiont-specific effects in Myc-signaling and fatty acid metabolism. These findings support a role for Fn and ETBF in potentiating tumorigenesis via the induction of a cancer stem cell-like transit-amplifying and enterocyte population and the disruption of CTL cytotoxic function.


Assuntos
Infecções Bacterianas , Neoplasias Colorretais , Humanos , Camundongos , Animais , Neoplasias Colorretais/patologia , Fusobacterium nucleatum , Carcinogênese , Bacteroides fragilis
3.
Behav Sci Law ; 42(1): 46-55, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38145476

RESUMO

Civil litigation involving the forensic neuropsychiatric evaluation of a personal injury case requires an assessment of damages and causation. The expert witness is obliged to integrate data from three critical sources of information: the review of records; the results of neuropsychological testing; and the findings from the clinical examination. In civil litigation involving a personal injury claim, the expert witness can be expected to address causation and prognosis of any neuropsychiatric damages. We discuss the undertaking of a forensic neuropsychiatric evaluation, psychiatric disorders often encountered in personal injury litigation, provide case vignettes and describe a number of special types of forensic neuropsychiatric evaluations, for example, Workers' Compensation, VA Disability and Social Security Disability.


Assuntos
Prova Pericial , Transtornos Mentais , Humanos , Transtornos Mentais/diagnóstico , Avaliação da Deficiência
4.
Nanoscale ; 16(1): 223-236, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38053416

RESUMO

A detailed comparison of the capabilities of electron microscopy and nano-infrared (IR) microscopy for imaging microbial nanostructures has been carried out for the first time. The surface sensitivity, chemical specificity, and non-destructive nature of spectroscopic mapping is shown to offer significant advantages over transmission electron microscopy (TEM) for the study of biological samples. As well as yielding important topographical information, the distribution of amides, lipids, and carbohydrates across cross-sections of bacterial (Escherichia coli, Staphylococcus aureus) and fungal (Candida albicans) cells was demonstrated using PiFM. The unique information derived from this new mode of spectroscopic mapping of the surface chemistry and biology of microbial cell walls and membranes, may provide new insights into fungal/bacterial cell function as well as having potential use in determining mechanisms of antimicrobial resistance, especially those targeting the cell wall.


Assuntos
Nanoestruturas , Microscopia de Força Atômica , Nanoestruturas/química , Microscopia Eletrônica de Transmissão , Candida albicans , Escherichia coli , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
5.
Environ Sci Pollut Res Int ; 30(58): 121558-121568, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37955728

RESUMO

Plastic pollution is now a ubiquitous feature of freshwater systems and the majority of this is fibrous. Here, we test the effects of plastic and cellulose-based fibres (polyester, cotton, and bamboo from commercial clothing) on fish host-parasite interactions using a freshwater fish host-parasite model system (guppy Poecilia reticulata-Gyrodactylus turnbulli). For uninfected fish, polyester exposure was associated with significantly higher mortality rates compared with the other two fibre types. For infected fish, whilst polyester and cotton exposure were not associated with any significant changes to parasite burdens, fish exposed to bamboo fibres had significantly reduced maximum parasite burdens compared with fish not exposed to any fibres, indicating that the bamboo fibres and/or associated dyes conferred some degree of resistance or tolerance. Whilst unable to determine the exact nature of the chemical dyes, when testing off-host parasite survival on exposure to the fibre dyes, cotton and particularly polyester dyes were associated with higher parasite mortality compared to bamboo. Overall, we add to the growing body of evidence which shows that polyester microplastic fibres and their associated dyes can be detrimental for both fish and parasite survival, and we highlight the need for increased transparency from textile industries on the chemical identity of fabric dyes.


Assuntos
Parasitos , Poecilia , Trematódeos , Animais , Plásticos , Celulose , Poliésteres , Gossypium
6.
bioRxiv ; 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37066368

RESUMO

Fusobacterium nucleatum (Fn) and enterotoxigenic Bacteroides fragilis (ETBF) are two pathobionts consistently enriched in the gut microbiomes of patients with colorectal cancer (CRC) compared to healthy counterparts and frequently observed for their direct association within tumors. Although several molecular mechanisms have been identified that directly link these organisms to features of CRC in specific cell types, their specific effects on the epithelium and local immune compartment are not well-understood. To fill this gap, we leveraged single-cell RNA sequencing (scRNA-seq) on wildtype mice and mouse model of CRC. We find that Fn and ETBF exacerbate cancer-like transcriptional phenotypes in transit-amplifying and mature enterocytes in a mouse model of CRC. We also observed increased T cells in the pathobiont-exposed mice, but these pathobiont-specific differences observed in wildtype mice were abrogated in the mouse model of CRC. Although there are similarities in the responses provoked by each organism, we find pathobiont-specific effects in Myc-signaling and fatty acid metabolism. These findings support a role for Fn and ETBF in potentiating tumorigenesis via the induction of a cancer stem cell-like transit-amplifying and enterocyte population and the disruption of CTL cytotoxic function.

7.
Phys Ther Sport ; 61: 185-191, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37116373

RESUMO

OBJECTIVE: Develop a questionnaire to monitor symptoms of player perceived shoulder function/dysfunction. DESIGN: 3-Stage Online Delphi Study. METHODS: Participants: surgeons, sports and exercise medics, academic researchers, strength and conditioning coaches, therapists and athletes split by level of expertise/experience. Stage-1: experts (n = 12) rated constructs/items from the steering group and made changes/proposed additional constructs/items. Stage-2: experts rated/amended new constructs/items from stage-1. Stage-3: experienced professionals (n = 25) rated/ranked constructs/items from stage 2. Consensus thresholds were defined per stage (≥50% agreement/4-5 rating on 1-5 Likert scale (stages 1-2), ≥68% agreement, and items ranked for perceived importance (stage-3)). RESULTS: Stage-1, all four constructs (a. Activities of daily living, b. Range of motion, c. Strength and conditioning, d. Sports specific training and competition) and 26/42 original items achieved consensus. Twelve items were combined into five items. Four new items were also proposed. Stage-2, the combined items and three of the four new items achieved consensus. Stage-3 the four constructs and 22 items all achieved consensus. CONCLUSIONS: Following a 3-stage online Delphi process, involving expert and experienced clinicians, practitioners and athletes, a new four construct, 22 item RSF questionnaire has been developed which can be used with rugby players, to monitor perceived shoulder performance and symptoms.


Assuntos
Rugby , Ombro , Humanos , Técnica Delphi , Atividades Cotidianas , Inquéritos e Questionários
8.
PLoS One ; 17(7): e0270336, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35797359

RESUMO

BACKGROUND: The evaluation of physical qualities in talent identification and development systems is vital and commonplace in supporting youth athletes towards elite sport. However, the complex and dynamic development of physical qualities in addition to temporal challenges associated with the research design, such as unstructured data collection and missing data, requires appropriate statistical methods to be applied in research to optimise the understanding and knowledge of long-term physical development. AIM: To collate and evaluate the application of methodological and statistical methods used in studies investigating the development of physical qualities within youth athletes. METHODS: Electronic databases were systematically searched form the earliest record to June 2021 and reference lists were hand searched in accordance with the PRISMA guidelines. Studies were included if they tested physical qualities over a minimum of 3 timepoints, were observational in nature and used youth sporting populations. RESULTS: Forty articles met the inclusion criteria. The statistical analysis methods applied were qualitatively assessed against the theoretical underpinnings (i.e. multidimensional development, non-linear change and between and within athlete change) and temporal challenges (i.e. time variant and invariant variables, missing data, treatment of time and repeated measures) encountered with longitudinal physical testing research. Multilevel models were implemented most frequently (50%) and the most appropriately used statistical analysis method when qualitatively compared against the longitudinal challenges. Independent groups ANOVA, MANOVA and X2 were also used, yet failed to address any of the challenges posed within longitudinal physical testing research. CONCLUSIONS: This methodological review identified the statistical methods currently employed within longitudinal physical testing research and addressed the theoretical and temporal challenges faced in longitudinal physical testing research with varying success. The findings can be used to support the selection of statistical methods when evaluating the development of youth athletes through the consideration of the challenges presented.


Assuntos
Esportes , Esportes Juvenis , Adolescente , Atletas , Humanos , Estudos Longitudinais , Projetos de Pesquisa
9.
Nanoscale Res Lett ; 15(1): 161, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32761390

RESUMO

The control of the growth of hematite nanoparticles from iron chloride solutions under hydrothermal conditions in the presence of two different structure promoters has been studied using a range of both structural and spectroscopic techniques including the first report of photo induced force microscopy (PiFM) to map the topographic distribution of the structure-directing agents on the developing nanoparticles. We show that the shape of the nanoparticles can be controlled using the concentration of phosphate ions up to a limit determined to be ~6 × 10-3 mol. Akaganéite (ß-FeOOH) is a major component of the nanoparticles formed in the absence of structure directors but only present in the very early stages (< 8 h) of particle growth when phosphate is present. The PiFM data suggest a correlation between the areas in which phosphate ions are adsorbed and areas where akaganéite persists on the surface. In contrast, goethite (α-FeOOH) is a directly observed precursor of the hematite nanorods when 1,2-diamino propane is present. The PiFM data shows goethite in the center of the developing particles consistent with a mechanism in which the iron hydroxide re-dissolves and precipitates at the nanorod ends as hematite.

10.
Sports Med Open ; 6(1): 14, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32086645

RESUMO

Rugby union (RU) is a skill-collision team sport played at junior and senior levels worldwide. Within England, age-grade rugby governs the participation and talent development of youth players. The RU player development pathway has recently been questioned, regarding player performance and well-being, which sport science research can address. The purpose of this review was to summarise and critically appraise the literature in relation to the applied sport science of male age-grade RU players in England focussing upon (1) match-play characteristics, (2) training exposures, (3) physical qualities, (4) fatigue and recovery, (5) nutrition, (6) psychological challenges and development, and (7) injury. Current research evidence suggests that age, playing level and position influence the match-play characteristics of age-grade RU. Training exposures of players are described as 'organised chaos' due to the multiple environments and stakeholders involved in coordinating training schedules. Fatigue is apparent up to 72 h post match-play. Well-developed physical qualities are important for player development and injury risk reduction. The nutritional requirements are high due to the energetic costs of collisions. Concerns around the psychological characteristics have also been identified (e.g. perfectionism). Injury risk is an important consideration with prevention strategies available. This review highlights the important multi-disciplinary aspects of sport science for developing age-grade RU players for continued participation and player development. The review describes where some current practices may not be optimal, provides a framework to assist practitioners to effectively prepare age-grade players for the holistic demands of youth RU and considers areas for future research.

11.
Int J Sports Physiol Perform ; 13(10): 1331-1336, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29745789

RESUMO

PURPOSE: To quantify the frequencies and timings of rugby union match-play phases (ie, attacking, defending, ball in play [BIP], and ball out of play [BOP]) and then compare the physical characteristics of attacking, defending, and BOP between forwards and backs. METHODS: Data were analyzed from 59 male rugby union academy players (259 observations). Each player wore a microtechnology device (OptimEye S5; Catapult, Melbourne, Australia) with video footage analyzed for phase timings and frequencies. Dependent variables were analyzed using a linear mixed-effects model and assessed with magnitude-based inferences and Cohen d effect sizes (ES). RESULTS: Attack, defense, BIP, and BOP times were 12.7 (3.1), 14.7 (2.5), 27.4 (2.9), and 47.4 (4.1) min, respectively. Mean attack (26 [17] s), defense (26 [18] s), and BIP (33 [24] s) phases were shorter than BOP phases (59 [33] s). The relative distance in attacking phases was similar (112.2 [48.4] vs 114.6 [52.3] m·min-1, ES = 0.00 ± 0.23) between forwards and backs but greater in forwards (114.5 [52.7] vs 109.0 [54.8] m·min-1, ES = 0.32 ± 0.23) during defense and greater in backs during BOP (ES = -0.66 ± 0.23). CONCLUSIONS: Total time in attack, defense, and therefore BIP was less than BOP. Relative distance was greater in forwards during defense, whereas it was greater in backs during BOP and similar between positions during attack. Players should be exposed to training intensities from in-play phases (ie, attack and defense) rather than whole-match data and practice technical skills during these intensities.

12.
Urol Case Rep ; 9: 9-11, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27617213

RESUMO

Adrenocortical carcinoma (ACC) is a rare malignancy that is generally associated with a poor prognosis whose existence dictates the management of incidental renal masses. We report a case of ACC diagnosed and treated at its apparent inception in a patient undergoing close surveillance imaging of a prior malignancy. Despite timely detection and resection of a localized ACC this patient rapidly progressed to systemic disease. This case highlights the rapid growth kinetics of ACC and puts into perspective the challenges associated with the established treatment paradigm for patients diagnosed with an adrenal mass.

13.
J Strength Cond Res ; 29(6): 1713-22, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25474341

RESUMO

The purpose of this study was to evaluate the annual and long-term (i.e., 4 years) development of anthropometric and physical characteristics in academy (16-20 years) rugby league players. Players were assessed at the start of preseason over a 6-year period and were required to be assessed on consecutive years to be included in the study (Under 16-17, n = 35; Under 17-18, n = 44; Under 18-19, n = 35; Under 19-20, n = 16). A subset of 15 players were assessed for long-term changes over 4 years (Under 16-19). Anthropometric (height, body mass, sum of 4 skinfolds) and physical (10- and 20-m sprint, 10-m momentum, vertical jump, yo-yo intermittent recovery test level 1, 1 repetition maximum [1RM] squat, bench press, and prone row) assessments were collected. Paired t-tests and repeated measures analysis of variance demonstrated significant annual (e.g., body mass, U16 = 76.4 ± 8.4, U17 = 81.3 ± 8.3 kg; p < 0.001, d = 0.59) and long-term (e.g., vertical jump, Under 16 = 44.1 ± 3.8, Under 19 = 52.1 ± 5.3 cm; p < 0.001, d = 1.74) changes in anthropometric and physical characteristics. Greater percentage changes were identified between the Under 16-17 age categories compared with the other ages (e.g., 1RM squat, U16-17 = 22.5 ± 19.5 vs. U18-19 = 4.8 ± 6.4%). Findings demonstrate the annual and long-term development of anthropometric and physical characteristics in academy rugby league players establishing greater changes occur at younger ages upon the commencement of a structured training program within an academy. Coaches should understand the long-term development of physical characteristics and use longitudinal methods for monitoring and evaluating player performance and development.


Assuntos
Desenvolvimento do Adolescente , Desempenho Atlético/fisiologia , Futebol Americano/fisiologia , Aptidão Física/fisiologia , Adolescente , Antropometria , Estatura , Peso Corporal , Teste de Esforço , Humanos , Força Muscular , Corrida/fisiologia , Dobras Cutâneas , Fatores de Tempo , Adulto Jovem
14.
Eur J Neurosci ; 35(7): 991-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22487030

RESUMO

Learning is proposed to occur when there is a discrepancy between reward prediction and reward receipt. At least two separate systems are thought to exist: one in which predictions are proposed to be based on model-free or cached values; and another in which predictions are model-based. A basic neural circuit for model-free reinforcement learning has already been described. In the model-free circuit the ventral striatum (VS) is thought to supply a common-currency reward prediction to midbrain dopamine neurons that compute prediction errors and drive learning. In a model-based system, predictions can include more information about an expected reward, such as its sensory attributes or current, unique value. This detailed prediction allows for both behavioral flexibility and learning driven by changes in sensory features of rewards alone. Recent evidence from animal learning and human imaging suggests that, in addition to model-free information, the VS also signals model-based information. Further, there is evidence that the orbitofrontal cortex (OFC) signals model-based information. Here we review these data and suggest that the OFC provides model-based information to this traditional model-free circuitry and offer possibilities as to how this interaction might occur.


Assuntos
Gânglios da Base/fisiologia , Lobo Frontal/fisiologia , Aprendizagem/fisiologia , Modelos Neurológicos , Rede Nervosa/fisiologia , Animais , Humanos
15.
PLoS One ; 6(2): e16715, 2011 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21379579

RESUMO

A causal role of mutations in multiple general transcription factors in neurodevelopmental disorders including autism suggested that alterations in global levels of gene expression regulation might also relate to disease risk in sporadic cases of autism. This premise can be tested by evaluating for changes in the overall distribution of gene expression levels. For instance, in mice, variability in hippocampal-dependent behaviors was associated with variability in the pattern of the overall distribution of gene expression levels, as assessed by variance in the distribution of gene expression levels in the hippocampus. We hypothesized that a similar change in variance might be found in children with autism. Gene expression microarrays covering greater than 47,000 unique RNA transcripts were done on RNA from peripheral blood lymphocytes (PBL) of children with autism (n = 82) and controls (n = 64). Variance in the distribution of gene expression levels from each microarray was compared between groups of children. Also tested was whether a risk factor for autism, increased paternal age, was associated with variance. A decrease in the variance in the distribution of gene expression levels in PBL was associated with the diagnosis of autism and a risk factor for autism, increased paternal age. Traditional approaches to microarray analysis of gene expression suggested a possible mechanism for decreased variance in gene expression. Gene expression pathways involved in transcriptional regulation were down-regulated in the blood of children with autism and children of older fathers. Thus, results from global and gene specific approaches to studying microarray data were complimentary and supported the hypothesis that alterations at the global level of gene expression regulation are related to autism and increased paternal age. Global regulation of transcription, thus, represents a possible point of convergence for multiple etiologies of autism and other neurodevelopmental disorders.


Assuntos
Transtorno Autístico/genética , Regulação da Expressão Gênica , Idade Paterna , Adulto , Algoritmos , Transtorno Autístico/sangue , Transtorno Autístico/etiologia , Transtorno Autístico/metabolismo , Células Sanguíneas/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Fatores de Risco , Estudos de Validação como Assunto , Adulto Jovem
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