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1.
Phys Ther Sport ; 65: 137-144, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38181564

RESUMO

BACKGROUND: Sub-concussive and concussive impacts sustained during contact sports such as rugby may affect neurocognitive performance, vestibular-ocular-motor function, symptom burden and academic ability. METHOD: Student-athletes (n = 146) participating in rugby union British Universities or domestic competitions were assessed on the Immediate Post-Concussion and Cognitive Test, Post-Concussion Symptom Scale, vestibular-oculo-motor screening tool and revised perceived academic impact tool. Individual change from pre-season (July-September 2021) to 2-weeks following last exposure to contact (April-July 2022) was analysed. RESULTS: Symptom burden significantly worsened (p=0.016) over the season. Significant improvements on verbal memory (p=0.016), visual memory (p=0.008) and motor processing speed (p=0.001) suggest a possible learning effect. Surprisingly, the number of days lost to concussion significantly and positively affected performance on verbal memory (p = 0.018) and reaction time (p = 0.027). Previous concussive events significantly predicted a worsening in symptom burden (p < 0.028), as did in-season concussive events, predicting improved verbal memory (p = 0.033) and symptom burden change (p = 0.047). Baseline performance significantly affected change on several neurocognitive tests, with low-scorers showing more improvement over the season. CONCLUSION: Participation in rugby union was not associated with deleterious effects on brain function. Previous concussive events and in-season factors, possibly related to learning effects, may explain improvement in cognitive function across the season.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Humanos , Idoso , Traumatismos em Atletas/diagnóstico , Rugby , Universidades , Estações do Ano , Concussão Encefálica/diagnóstico , Atletas , Estudantes
2.
J Biomech ; 155: 111666, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37263075

RESUMO

Over the past fifty years there has been considerable development in motion analysis systems and in computer simulation modelling of sports movements while the relevance and importance of functional variability of sports technique has become increasingly recognised. Technical developments for experimental work have led to increased, and still increasing, subject numbers. Increased subjects per study give better statistical power, the ability to utilise different data analyses, and thus the determination of more subtle and nuanced factors. The overall number of studies has also increased massively. Most actions in sport can, and have, been studied at some level with even the more challenging ones, such as player on player impacts, having some developing research. Computer simulation models of sports movements have ranged from simple (one or two segment) models to very complex musculoskeletal models and have used parameters ranging from the generic to individual-specific. Simple models have given insights into the key mechanics of movement while individual-specific model optimisations have been used to improve athlete performance. Our depth of understanding of the mechanics of sports techniques has increased across a wide range of sports. In the future there is likely to be more development and use of markerless motion capture, individual-specific model parameters, and more consideration of motor control aspects in the analysis of sports technique.


Assuntos
Desempenho Atlético , Humanos , Simulação por Computador , Fenômenos Biomecânicos , Movimento , Movimento (Física)
3.
Brain Inj ; 36(4): 455-468, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35377822

RESUMO

BACKGROUND: Physiological differences between a maturing and matured brain alters how Sports-Related Concussion (SRC) affects different age groups; therefore, a review specific to university-aged student-athletes is needed. OBJECTIVES: Determine time to recovery for symptom burden, neurocognitive and Vestibular-Ocular-Motor (VOM) function and academic impact in university-aged student-athletes. METHODS: Searches were conducted in PubMed, SpringerLink, PsycINFO, Science Direct, Scopus, Cochrane, Web of Science and EMBASE. Articles were included if they contained original data collected within 30 days in university-aged student-athletes, analysed SRC associated symptoms, neurocognitive or VOM function or academic ability and published in English. Two reviewers independently reviewed sources, using the Oxford Classification of Evidence-Based Medicine (CEBM) and the Downs and Black checklist, and independently extracting data before achieving consensus. RESULTS: 58 articles met the inclusion criteria. Recovery of symptoms occurred by 7 and 3-5.3 days for neurocognition. The evidence base did not allow for a conclusion on recovery time for VOM function or academic ability. Few papers investigated recovery times at specified re-assessment time-points and have used vastly differing methodologies. CONCLUSIONS: To fully understand the implication of SRC on the university-aged student-athlete' studies using a multi-faceted approach at specific re-assessments time points are required.Systematic review registration number: CRD42019130685.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Idoso , Atletas , Traumatismos em Atletas/complicações , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico , Humanos , Estudantes , Universidades
4.
Phys Ther Sport ; 52: 287-296, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34715487

RESUMO

BACKGROUND: Time to recovery for symptom burden and neurocognition following a Sports-Related Concussion (SRC) has previously been determined by consolidating varying re-assessment time points into a singular point, and has not been established for Vestibular-Ocular-Motor (VOM) function or academic ability. OBJECTIVES: Establish when recovery of symptom burden, neurocognition, VOM function, and academic ability occurs in university-aged student-athletes. METHODS: Student-athletes completed an assessment battery (Post-Concussion Symptom Scale (PCSS), Immediate Post-Concussion Assessment and Cognitive Test (ImPACT), Vestibular Ocular-Motor Screening (VOMS), Perceived Academic Impairment Tool (PAIT)) during pre-season (n = 140), within 48 hours, 4, 8 and 14 days post-SRC and prior to Return To Play (RTP) and were managed according to the Rugby Football Union' community pathway (n = 42). Student-athletes were deemed recovered or impaired according to Reliable Change Index' (RCI) or compared to their individual baseline. RESULTS: Symptom burden recovers by four days post-SRC on RCI and to baseline by eight days. VOM function and academic ability recovers by 8 days. Some student-athletes demonstrated worse performance at RTP on all tests by RCI and to baseline, except for on VOMS score and near point convergence by RCI change. CONCLUSIONS: Variation in individual university-aged student-athletes requires a multi-faceted approach to establish what dysfunctions post-SRC exist and when recovery occurs.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Futebol Americano , Idoso , Atletas , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Humanos , Estudos Prospectivos , Estudantes , Universidades
5.
Brain Inj ; 35(7): 788-797, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33896286

RESUMO

Introduction: Research indicates Sports-Related Concussion (SRC) impairs Vestibular-Ocular-Motor (VOM) function. The aim was to explore if VOM impairment correlates with longer Return To Play (RTP), symptom burden, neurocognitive performance and academic capability.Participants: 40 (61.4% male) Loughborough University, UK, rugby union student-athletes who sustained 42 SRCs.Methods: Student-athletes completed an assessment battery during pre-season (baseline), 2, 4, 8 and 14 days post-SRC and prior to RTP and were managed according to the rugby Football Union' community pathway.Outcome measures: Vestibular Ocular-Motor Screening (VOMS), Immediate Post-Concussion Assessment and Cognitive Test, Post-Concussion Symptom Scale, Perceived Academic Impairment Tool questionnaire and percentage of academic activities specifically missed due to SRC.Results: VOMS scores were significantly (p < 0.005) greater than baseline at all time points except RTP. Presence of VOM dysfunction at 14 days post-SRC significantly correlated with a longer RTP, greater symptom burden and increased odds ratio at 2, 4 and 8 days and academic time loss at 2, 4 and 8 days post-SRC.Conclusion: VOM impairment is associated with an increased symptom burden and impaired academic capability, and a longer time to RTP when present at 14 days post-SRC.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Atletas , Traumatismos em Atletas/complicações , Concussão Encefálica/complicações , Feminino , Humanos , Masculino , Volta ao Esporte , Estudantes
7.
Respir Res ; 18(1): 208, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29237464

RESUMO

BACKGROUND: Airway epithelial cells (AEC) act as the first line of defence in case of lung infections. They constitute a physical barrier against pathogens and they participate in the initiation of the immune response. Yet, the modalities of pathogen recognition by AEC and the consequences on the epithelial barrier remain poorly documented. METHOD: We investigated the response of primary human AEC to viral (polyinosinic-polycytidylic acid, poly(I:C)) and bacterial (lipopolysaccharide, LPS) stimulations in combination with the lung remodeling factor Transforming Growth Factor-ß (TGF-ß). RESULTS: We showed a strong production of pro-inflammatory cytokines (Interleukin (IL)-6, Tumor Necrosis Factor α, TNFα) or chemokines (CCL2, CCL3, CCL4, CXCL10, CXCL11) by AEC stimulated with poly(I:C). Cytokine and chemokine production, except CXCL10, was Toll Like Receptor (TLR)-3 dependent and although they express TLR4, we found no cytokine production after LPS stimulation. Poly(I:C), but not LPS, synergised with TGF-ß for the production of matrix metalloproteinase-9 (MMP-9) and fibronectin. Mechanistic analyses suggest the secretion of Wnt ligands by AEC along with a degradation of the cellular junctions after poly(I:C) exposure, leading to the release of ß-catenin from the cell membrane and stimulation of the Wnt/ß-catenin pathway. CONCLUSION: Our results highlight the cross talk between TGF-ß and TLR signaling in bronchial epithelium and its impact on the remodeling process.


Assuntos
Metaloproteinase 9 da Matriz/biossíntese , Mucosa Respiratória/metabolismo , Receptor 3 Toll-Like/biossíntese , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Células Cultivadas , Quimiocinas/metabolismo , Citocinas/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Receptor Cross-Talk/efeitos dos fármacos , Receptor Cross-Talk/fisiologia , Mucosa Respiratória/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos
8.
Am J Transplant ; 17(6): 1502-1514, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27982503

RESUMO

Chronic lung allograft dysfunction (CLAD) is the major limitation of long-term survival after lung transplantation. CLAD manifests as bronchiolitis obliterans syndrome (BOS) or restrictive allograft syndrome (RAS). Alloimmune reactions and epithelial-to-mesenchymal transition have been suggested in BOS. However, little is known regarding the role of allogenicity in epithelial cell differentiation. Primary human bronchial epithelial cells (BECs) were treated with activated T cells in the presence or absence of transforming growth factor (TGF)-ß. The expression of epithelial and mesenchymal markers was investigated. The secretion of inflammatory cytokines and matrix metalloproteinase (MMP)-9 was measured in culture supernatants and in plasma from lung transplant recipients (LTRs): 49 stable, 29 with BOS, and 16 with RAS. We demonstrated that C-C motif chemokine 2 secreted by T cells supports TGF-ß-induced MMP-9 production by BECs after binding to C-C chemokine receptor type 2. Longitudinal investigation in LTRs revealed a rise in plasma MMP-9 before CLAD onset. Multivariate analysis showed that plasma MMP-9 was independently associated with BOS (odds ratio [OR] = 6.19, p = 0.002) or RAS (OR = 3.9, p = 0.024) and predicted the occurrence of CLAD 12 months before the functional diagnosis. Thus, immune cells support airway remodeling through the production of MMP-9. Plasma MMP-9 is a potential predictive biomarker of CLAD.


Assuntos
Biomarcadores/sangue , Células Epiteliais/imunologia , Rejeição de Enxerto/diagnóstico , Pneumopatias/complicações , Transplante de Pulmão/efeitos adversos , Metaloproteinase 9 da Matriz/sangue , Receptores CCR2/metabolismo , Linfócitos T/imunologia , Adulto , Aloenxertos , Brônquios/imunologia , Brônquios/metabolismo , Brônquios/patologia , Doença Crônica , Citocinas/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Seguimentos , Rejeição de Enxerto/sangue , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/imunologia , Humanos , Estudos Longitudinais , Pneumopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Fatores de Risco , Linfócitos T/metabolismo , Fator de Crescimento Transformador beta/metabolismo
9.
BMC Public Health ; 16(1): 1143, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27825373

RESUMO

BACKGROUND: Body dissatisfaction is associated with a range of adverse outcomes, including impaired psychological health, low physical activity and disordered eating. This longitudinal study used the Factors Influencing Transitions in Girls' Active Leisure and Sport (FITGALS) dataset to examine trends in body image of adolescent females. Specifically, the study examined satisfaction with body size, physical appearance and dieting behaviour for two cohorts at transitional life phases in two geographic regions longitudinally over a 3-year period. METHODS: A sample of 732 adolescent females in Grade 7 (n = 489, 66.8 %) and Grade 11 (n = 243, 33.2 %) at randomly selected Australian metropolitan and non-metropolitan secondary schools responded to a questionnaire in three successive years from 2008 to 2010. Participants reported perceptions about their body size and physical appearance and whether they were, or ought to be, on a diet. The data were analysed using a series of longitudinal logistic regression models. RESULTS: Dieting and dissatisfaction with body size significantly increased over time and more so for older than younger girls. Region significantly moderated the effect of grade level regarding dissatisfaction with body size but not dieting. In non-metropolitan regions, those in the younger cohort were significantly more likely to be dissatisfied with their body size than the older cohort; whereas in metropolitan regions, those in the older cohort were significantly more likely to be dissatisfied with their body size than the younger cohort. Adolescent female's perceptions of their appearance were unchanged over time, region and grade level. CONCLUSIONS: Differences across time, region and grade level were found among adolescent females on body size and dieting behaviour, but not physical appearance. Adolescent females experience early and increasing body size dissatisfaction and dieting as they age, but stable perceptions of physical appearance. Age and geographic region are important considerations for the timing and targeting of interventions to address body image concerns. Further investigation of regional differences in body image perceptions and factors that affect these is warranted. The findings of this study highlight the ongoing need for strategies during adolescence to promote a healthy appreciation of body size and appearance.


Assuntos
Comportamento do Adolescente/psicologia , Imagem Corporal , Tamanho Corporal , Dieta Redutora/psicologia , Comportamento Alimentar/psicologia , Satisfação Pessoal , Aparência Física , Adolescente , Austrália , Peso Corporal , Criança , Cidades , Exercício Físico , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Feminino , Humanos , Estudos Longitudinais , Saúde Mental , Instituições Acadêmicas , Análise Espacial , Inquéritos e Questionários
10.
Rev Mal Respir ; 33(7): 565-72, 2016 Sep.
Artigo em Francês | MEDLINE | ID: mdl-26803449

RESUMO

INTRODUCTION: Anemia occurs commonly in COPD and is associated with a poor prognosis. The role of comorbidities in this is suspected but poorly characterized and the economic implications of anemia combined with COPD in France have not been studied. The healthcare resource utilization and cost impact of anemia remain to be investigated. METHODS: One hundred and fifty-one COPD patients attending a pulmonology outpatient department during a 6 months period were retrospectively selected if they had undergone a pulmonary function test, a blood gas analysis or a blood count. The Charlson comorbidity index, resource utilization and economic data from the year before the diagnosis of anemia were compared between anemic and non-anemic patients as well as 3-year survival analysis. RESULTS: The prevalence of anemia was 18.5% and was not influenced by GOLD stage. The identification of anemia was similar from blood gas results and full blood count analysis. Comorbidities - mainly cardiovascular - were found in 86% of the anemic patients. The Charlson index was 5.4±2 in the anemic group compared to 4.1±1.5 in the non-anemic group (P<0.01). The Charlson index was the only predictive factor of anemia using logistic regression analysis. The 3-year mortality was 36% in the anemic versus 7% in the non-anemic group (P<0.05). The main factor identified which predicted 3-year mortality was the presence of anemia using logistic regression. Healthcare costs the year prior to the diagnosis of anemia were not significantly different between groups, but there was a tendency to an increase in the cost of the hospitalizations in the anemic group. CONCLUSIONS: Anemia is easy to diagnose in COPD from the blood gas analysis. It is frequently linked to the presence of comorbidities - mainly cardiovascular diseases - and is the more important predictive factor of the 3-year mortality. There was a tendency towards an increase in the costs of hospitalizations in anemic patients but this remains to be confirmed in a larger economic study.


Assuntos
Anemia/economia , Anemia/epidemiologia , Custos de Cuidados de Saúde , Doença Pulmonar Obstrutiva Crônica/economia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Idoso , Anemia/complicações , Anemia/mortalidade , Gasometria , Doenças Cardiovasculares/economia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Comorbidade , Feminino , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/mortalidade , Testes de Função Respiratória , Estudos Retrospectivos , Análise de Sobrevida
11.
J Oral Rehabil ; 38(9): 655-60, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21314708

RESUMO

Occlusal indicators are widely used in dental treatment to measure tooth contacts that occur during occlusion. However, the presence of an indicator may affect the mechanics of occlusion and lead to invalid tooth contact data. The objective of this study was to determine the effect of four indicators (Parkell, silk, T-Scan(®) sensor and paper) on surface electromyography (SEMG) activity during occlusion. Twenty-three subjects performed strong bites and maximum clenches onto the four indicators and natural dentition. Surface electromyography recordings of anterior temporalis and superficial masseter activity and the subjects' perception of each indicator were measured. SEMG activity with the T-Scan(®) sensor and paper was significantly different (higher masseter activity; P < 0·05) compared to that for natural dentition. The Parkell and silk gave no significant differences to natural dentition. Similarly, subjects perceived that T-Scan(®) sensor and paper had the greatest effect on occlusion and were the least comfortable (P < 0·05). Thus, the very plastic T-Scan(®) sensor and very thick articulating paper both affected SEMG activity during occlusion and, therefore, may not provide valid tooth contact information for dental treatment. In conclusion, occlusal indicators can change SEMG activity during occlusion which may affect the validity of the measurements they provide.


Assuntos
Materiais Dentários , Oclusão Dentária , Má Oclusão/diagnóstico , Músculo Masseter/fisiologia , Músculo Temporal/fisiologia , Adulto , Eletromiografia/métodos , Feminino , Humanos , Registro da Relação Maxilomandibular/métodos , Masculino , Papel , Reprodutibilidade dos Testes , Seda , Adulto Jovem
12.
J Biomech ; 44(5): 955-61, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21159340

RESUMO

Strength, or maximum joint torque, is a fundamental factor governing human movement, and is regularly assessed for clinical and rehabilitative purposes as well as for research into human performance. This study aimed to identify the most appropriate protocol for fitting a maximum voluntary torque function to experimental joint torque data. Three participants performed maximum isometric and concentric-eccentric knee extension trials on an isovelocity dynamometer and a separate experimental protocol was used to estimate maximum knee extension angular velocity. A nine parameter maximum voluntary torque function, which included angle, angular velocity and neural inhibition effects, was fitted to the experimental torque data and three aspects of this fitting protocol were investigated. Using an independent experimental estimate of maximum knee extension angular velocity gave lower variability in the high concentric velocity region of the maximum torque function compared to using dynamometer measurements alone. A weighted root mean square difference (RMSD) score function, that forced the majority (73-92%) of experimental data beneath the maximum torque function, was found to best account for the one-sided noise in experimental torques resulting from sub-maximal effort by the participants. The suggested protocol (an appropriately weighted RMSD score function and an independent estimate of maximum knee extension angular velocity) gave a weighted RMSD of between 11 and 13 Nm (4-5% of maximum isometric torque). It is recommended that this protocol be used in generating maximum voluntary joint torque functions in all torque-based modelling of dynamic human movement.


Assuntos
Articulações/patologia , Adulto , Fenômenos Biomecânicos , Biofísica/métodos , Humanos , Contração Isométrica/fisiologia , Cinética , Joelho/fisiologia , Articulação do Joelho/fisiologia , Movimento (Física) , Movimento , Contração Muscular/fisiologia , Músculo Esquelético/patologia , Torque
13.
J Oral Rehabil ; 37(9): 663-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20492437

RESUMO

This study aimed to measure neuromuscular function for the masticatory muscles under a range of occlusal conditions in healthy, dentate adults. Forty-one subjects conducted maximum voluntary clenches under nine different occlusal loading conditions encompassing bilateral posterior teeth contacts with the mandible in different positions, anterior teeth contacts and unilateral posterior teeth contacts. Surface electromyography was recorded bilaterally from the anterior temporalis, superficial masseter, sternocleidomastoid, anterior digastric and trapezius muscles. Clench condition had a significant effect on muscle function (P = 0.0000) with the maximum function obtained for occlusions with bilateral posterior contacts and the mandible in a stable centric position. The remaining contact points and moving the mandible to a protruded position, whilst keeping posterior contacts, resulted in significantly lower muscle activities. Clench condition also had a significant effect on the per cent overlap, anterior-posterior and torque coefficients (P = 0.0000-0.0024), which describe the degree of symmetry in these muscle activities. Bilateral posterior contact conditions had significantly greater symmetry in muscle activities than anterior contact conditions. Activity in the sternocleidomastoid, anterior digastric and trapezius was consistently low for all clench conditions, i.e. <20% of the maximum voluntary contraction level. In conclusion, during maximum voluntary clenches in a healthy population, maximum masticatory muscle activity requires bilateral posterior contacts and the mandible to be in a stable centric position, whilst with anterior teeth contacts, both the muscle activity and the degree of symmetry in muscle activity are significantly reduced.


Assuntos
Oclusão Dentária , Músculos da Mastigação/fisiologia , Junção Neuromuscular/fisiologia , Adulto , Dente Pré-Molar/anatomia & histologia , Força de Mordida , Oclusão Dentária Central , Eletromiografia , Feminino , Humanos , Incisivo/anatomia & histologia , Masculino , Mandíbula/anatomia & histologia , Músculo Masseter/fisiologia , Dente Molar/anatomia & histologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Músculos do Pescoço/fisiologia , Músculo Temporal/fisiologia , Fatores de Tempo , Torque , Adulto Jovem
14.
J Biomech ; 43(2): 364-9, 2010 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-19840881

RESUMO

In landings from a flight phase the mass centre of an athlete experiences rapid decelerations. This study investigated the extent to which co-contraction is beneficial or necessary in drop landings, using both experimental data and computer simulations. High speed video and force recordings were made of an elite martial artist performing drop landings onto a force plate from heights of 1.2, 1.5 and 1.8m. Matching simulations of these landings were produced using a planar 8-segment torque-driven subject-specific computer simulation model. It was found that there was substantial co-activation of joint flexor and extensor torques at touchdown in all three landings. Optimisations were carried out to determine whether landings could be effected without any co-contraction at touchdown. The model was not capable of landing from higher than 1.05m with no initial flexor or extensor activations. Due to the force-velocity properties of muscle, co-contraction with net zero joint torque at touchdown leads to increased extensor torque and decreased flexor torque as joint flexion velocity increases. The same considerations apply in any activity where rapid changes in net joint torque are required, as for example in jumps from a running approach.


Assuntos
Modelos Biológicos , Contração Muscular/fisiologia , Esportes/fisiologia , Adulto , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos , Simulação por Computador , Articulação do Quadril/fisiologia , Humanos , Articulação do Joelho/fisiologia , Modelos Lineares , Masculino , Artes Marciais/fisiologia , Corrida/fisiologia , Atletismo/fisiologia
15.
Int J Sports Med ; 30(10): 713-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19764007

RESUMO

Standing arm-cranking ('grinding') is predominantly an upper-body exercise, however, the contribution of the legs to this activity is unknown. The purpose of the study was to examine the influence of normal lower-limb movement on physiological strain during arm-cranking. Eight elite professional America's Cup grinders performed two exercise trials, on an adjustable standing arm-crank ergometer with SRM powercrank, in a cross-over design. Each trial comprised of two 5-min stages at the same work rate ( approximately lactate threshold) with the knee joint splinted or normal movement available. Vertical ground reaction forces (VGRF) and knee joint angle were determined from two force plates and sagittal plane video, respectively. Work rate was identical for the two conditions (246 (14) vs. 246 (13) W, p=0.7). Knee joint range of motion and unilateral VGRF amplitude were greater during normal compared with splinted arm-cranking (both p<0.01). There was no difference in VO2 (p=0.2) between the two conditions, however, there was greater VCO2 (8%, p=0.001), RER (11%, p<0.001), V(E) (17%, p<0.001) and HR (7 (3) beats.min(-1), p<0.001) during splinted compared with normal arm-cranking. Furthermore, the rise in BLa was greater after splinted than normal arm-cranking (4.8 (0.8) vs. 3.7 (1.0) mmol.L(-1), p=0.04). These data suggest that the lower-limbs play an integral role in standing arm-cranking, and restricted leg movement markedly affects the cardiovascular and metabolic responses to this activity.


Assuntos
Braço/fisiologia , Desempenho Atlético/fisiologia , Extremidade Inferior/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , América , Estudos Cross-Over , Ergometria , Humanos , Lactatos/sangue , Masculino , Esforço Físico , Testes de Função Respiratória , Rotação , Extremidade Superior/fisiologia
16.
Eur Respir J ; 32(2): 362-71, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18353854

RESUMO

Airway mesenchymal cells, such as myofibroblasts and airway smooth muscle cells, contribute to inflammation, airway remodelling and hyperresponsiveness in asthma by excessive proliferation and inflammatory mediator production. Using endobronchial biopsies obtained from both nonasthmatic and asthmatic subjects, in situ proliferation was assessed by immunostaining for cyclin D1. The number of immunoreactive cells increased with asthma severity and was restricted to the epithelium and subepithelial connective tissue. Despite increases in smooth muscle area, cyclin D1 was not detected in cells in intact muscle bundles. Biopsy-derived cell cultures were characterised as predominantly myofibroblasts, and were assessed to determine whether proliferation and cytokine production varied with asthma status. Cell enumeration showed that basal proliferation was similar in cells from nonasthmatics and asthmatics, and mitogenic responses to fibroblast growth factor-2, thrombin or serum were either reduced or unchanged in cells from asthmatics. Interleukin (IL)-1-dependent granulocyte-macrophage colony-stimulating factor and IL-8 release was increased in cell supernatants from asthmatics. Thus, increased rates of cellular proliferation identified in situ in the asthmatic airway occurred outside the expanded smooth muscle compartment. Although reduced proliferative responses were observed in cultured myofibroblasts from asthmatics, the increased cytokine production by these cells suggests that this contributes to and may perpetuate ongoing inflammation in asthma.


Assuntos
Albuterol/análogos & derivados , Androstadienos/farmacologia , Asma/metabolismo , Fibroblastos/metabolismo , Músculo Liso/metabolismo , Músculos/metabolismo , Traqueia/metabolismo , Adulto , Albuterol/farmacologia , Broncodilatadores/farmacologia , Proliferação de Células , Ciclina D1/metabolismo , Feminino , Fluticasona , Humanos , Masculino , Pessoa de Meia-Idade , Xinafoato de Salmeterol
17.
Br J Sports Med ; 40(5): 477-82; discussion 482-3, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16632584

RESUMO

In 2002, Tennis Australia commissioned a report into the experiences of elite female past players on leaving the professional tennis circuit. Australian players who were in the top 800 of the Women's Tennis Association (WTA) end of year rankings and who had left the professional circuit within the previous 15 years were asked by mail to respond to a questionnaire. The questionnaire asked players to describe their feelings about leaving the tour during the time leading up to leaving the tour to two years after retirement. The main findings of the study suggested that those who planned to leave the tour found the transition process easy, whereas those who did not plan to leave the tour found the process difficult. Most players (66%) did not regret leaving the tour, and, although the remaining players responded that they regretted leaving, none attempted a comeback. Tennis Australia has implemented strategies to assist current players on the professional tour based on the results of this study.


Assuntos
Aposentadoria/psicologia , Tênis/psicologia , Austrália , Comportamento Competitivo , Feminino , Humanos , Inquéritos e Questionários
18.
Ann Biol Clin (Paris) ; 63(6): 653-9, 2005.
Artigo em Francês | MEDLINE | ID: mdl-16330386

RESUMO

The WHO classification describes a group of myelodysplastic/myeloproliferative diseases, including a provisional entity, refractory anaemia with ringed sideroblasts (RARS) associated with marked thrombocytosis, underlining that is a provisional entity without consensus of belonging to myelodysplastic rather than to myeloproliferative syndromes. The authors report two cases with features of refractory anaemia with excess of ringed sideroblasts and marked thrombocytosis. In the first case, RARS is concomitant with thrombocytosis and fits the WHO criteria for this temporary entity. The second case is a typical RARS, who developed a thrombocytosis after several years and emphasizes that a link, at least progressive, exists between RARS and myeloproliferative disorders. The authors summed up the various situations related to secondary or primary acquired sideroblastic anaemia, likewise to primitive and reactive thrombocytosis. The cases of RARS + marked thrombocytosis reported in the literature are few in number and do not allow to settle between a particular form of myelodysplastic syndrome and a myeloproliferative disorder, a fully justified reason to classify these patients in a temporary group. To date, there is no codified therapy for this disorders.


Assuntos
Anemia Sideroblástica/classificação , Anemia Sideroblástica/complicações , Trombocitose/complicações , Idoso , Idoso de 80 Anos ou mais , Anemia Sideroblástica/patologia , Feminino , Neoplasias Hematológicas/classificação , Neoplasias Hematológicas/complicações , Humanos , Masculino , Índice de Gravidade de Doença , Trombocitose/patologia , Organização Mundial da Saúde
19.
Bone Marrow Transplant ; 35(9): 903-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15765111

RESUMO

To decrease red blood cell (RBC) transfusion requirements during high-dose therapy (HDT) for hematological malignancies, we conducted a pilot study to assess the effect of recombinant human erythropoietin (rHuEpo) given during chemotherapy before HDT and autologous peripheral stem-cell transplantation (APSCT). The transfusion histories of 15 HDT and APSCT for hematological disease performed in 11 consecutive patients who received rHuEpo (10 000 U subcutaneously three times/week) were compared to those of 22 HDT and ASCT performed in 17 consecutive historical controls matched for hematological parameters. rHuEpo increased the hemoglobin (Hb) level from 10.3+/-2.3 g/dl at diagnosis to 12.9+/-2.2 g/dl at the time of HDT in 11 patients; no major adverse effects occurred. Compared to historical controls (95%, 21/22), RBC transfusion requirements were significantly lower for rHuEpo recipients (26%, 4/15) (P=0.00001) and rHuEpo responders (15%, 2/13) (P=0.000002). After HDT and APSCT, fewer RBC transfusions were needed: 3.3, 1.2 and 0.3 RBC units for controls, rHuEpo recipients and rHuEpo responders, respectively (P=0.006 and 0.00002). Therefore, rHuEpo should be administered before, and not after HDT and APSCT, to lower RBC transfusion requirements after HDT and APSCT.


Assuntos
Transfusão de Eritrócitos , Eritropoetina/administração & dosagem , Linfoma de Célula do Manto/terapia , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico , Adulto , Idoso , Humanos , Linfoma de Célula do Manto/sangue , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Projetos Piloto , Proteínas Recombinantes , Transplante Autólogo
20.
Br J Sports Med ; 38(3): 337-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15155439

RESUMO

The case is reported of a 40 year old male high risk sport athlete who had seriously injured himself several times and as a result was partially physically disabled and had trouble with mental tasks requiring concentration such as spelling, reading numbers, and writing. The athlete was referred to a sports psychologist. In consultations, it became clear that he was having difficulty reconciling the difference between his life as it used to be and as it would be in the future. Part of his difficulty was dealing with the frustration and anger "outbursts" which resulted from not being able to perform straightforward everyday motor skills. In spite of his injuries and disability, the patient badly wanted to continue participating in extreme sports. Reversal theory is used in the discussion to provide theoretical explanations of the motivation for his extreme risk taking behaviour.


Assuntos
Traumatismos em Atletas/psicologia , Traumatismo Múltiplo/psicologia , Assunção de Riscos , Adaptação Psicológica , Adulto , Ira , Nível de Alerta , Traumatismos em Atletas/etiologia , Dano Encefálico Crônico/etiologia , Dano Encefálico Crônico/psicologia , Humanos , Masculino , Traumatismo Múltiplo/etiologia
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