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1.
Behav Res Methods ; 50(2): 662-672, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28455794

RESUMO

The Montreal Battery for the Evaluation of Amusia (MBEA; Peretz, Champod, & Hyde Annals of the New York Academy of Sciences, 999, 58-75, 2003) is an empirically grounded quantitative tool that is widely used to identify individuals with congenital amusia. The use of such a standardized measure ensures that the individuals tested will conform to a specific neuropsychological profile, allowing for comparisons across studies and research groups. Recently, a number of researchers have published credible critiques of the usefulness of the MBEA as a diagnostic tool for amusia. Here we argue that the MBEA and its online counterpart, the AMUSIA tests (Peretz et al. Music Perception, 25, 331-343, 2008), should be considered steps in a screening process for amusia, rather than standalone diagnostic tools. The goal of this article is to present, in detailed and easily replicable format, the full protocol through which congenital amusics should be identified. In providing information that has often gone unreported in published articles, we aim to clarify the strengths and limitations of the MBEA and to make recommendations for its continued use by the research community as part of the Montreal Protocol for Identification of Amusia.


Assuntos
Percepção Auditiva/fisiologia , Transtornos da Percepção Auditiva/diagnóstico , Testes Neuropsicológicos , Humanos , Estudos Longitudinais , Programas de Rastreamento/métodos , Memória de Curto Prazo/fisiologia , Música/psicologia
2.
Scand J Med Sci Sports ; 26(3): 256-65, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25809339

RESUMO

The purpose of this study was to quantify ball flight kinematics (ball speed, spin rate, spin axis orientation, seam orientation) and release location variability in the four most common pitch types in baseball and relate them to in-season pitching performance. Nine NCAA Division I pitchers threw four pitching variations (fastball, changeup, curveball, and slider) while a radar gun measured ball speed and a 600-Hz video camera recorded the ball trajectory. Marks on the ball were digitized to measure ball flight kinematics and release location. Ball speed was highest in the fastball, though spin rate was similar in the fastball and breaking pitches. Two distinct spin axis orientations were noted: one characterizing the fastball and changeup, and another, the curveball and slider. The horizontal release location was significantly more variable than the vertical release location. In-season pitching success was not correlated to any of the measured variables. These findings are instructive for inferring appropriate hand mechanics and spin types in each of the four pitches. Coaches should also be aware that ball flight kinematics might not directly relate to pitching success at the collegiate level. Therefore, talent identification and pitching evaluations should encompass other (e.g., cognitive, psychological, and physiological) factors.


Assuntos
Desempenho Atlético/fisiologia , Beisebol/fisiologia , Atletas , Fenômenos Biomecânicos , Interpretação Estatística de Dados , Mãos , Humanos , Masculino , Adulto Jovem
4.
Calcif Tissue Int ; 88(4): 325-35, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21212941

RESUMO

The role of exercise in promoting bone health is typically attributed to increased mechanical loading, which induces functional adaptation. Recent evidence suggests that habitual aerobic exercise has influence at the cellular level as well. The effect of aerobic capacity on osteoblast-lineage cell differentiation and function as well as skeletal phenotype is unknown. Using a rat model of high-capacity and low-capacity runners (HCRs and LCRs, respectively), in which an intrinsic functional genomic difference in aerobic capacity exists between nontrained animals, this study evaluated the effects of aerobic capacity on measures of bone mass and strength as well as osteoblast activity following ovariectomy. The ovariectomized rat emulates the clinical features of the estrogen-depleted human skeleton and represents a valuable model for studying short-term upregulation of osteoblast activity. We hypothesized that intrinsically high aerobic capacity would augment osteoblast response, which would mitigate the deleterious effects of hormone withdrawal. Femora and tibiae were assessed by micro-computed tomography, mechanical testing, and dynamic histomorphometry. HCRs had enhanced femoral tissue mineral density and estimated elastic modulus relative to LCRs. At 4 weeks postovariectomy, HCRs demonstrated a more robust osteoblast response. Markers of bone formation were upregulated to a greater extent in HCRs than LCRs, suggesting a role for aerobic capacity in governing osteoblast activity. Results from this and future studies will help to identify the influence of cellular aerobic metabolism on bone health, which may lead to new strategies for targeting diseases of the skeleton.


Assuntos
Osteoblastos/metabolismo , Ovariectomia/métodos , Oxigênio/metabolismo , Animais , Osso e Ossos/metabolismo , Elasticidade , Tolerância ao Exercício , Feminino , Fêmur/patologia , Hormônios/metabolismo , Modelos Biológicos , Condicionamento Físico Animal , Ratos , Estresse Mecânico , Microtomografia por Raio-X/métodos
5.
Comput Methods Biomech Biomed Engin ; 11(4): 379-87, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18568832

RESUMO

Bone is a dynamic tissue that undergoes structural modification in response to its mechanical environment, but how bone cells sense and respond to loading conditions remains incompletely understood. Current theories focus on strain-induced fluid flow for the primary means of mechanotransduction. To examine the influence of age-related cortical rarefaction on lacunocanalicular fluid characteristics, coupled fluid flow and mechanical computational models of bone specimens representing young, mid-age and aged samples were derived artificially from the same original micro-computed tomography image data. Simulated mechanical loading was applied to the bone models to induce pressure-driven interstitial fluid flow. Results demonstrated a decrease in pore pressure and fluid velocity magnitudes with age as a result of increased cortical porosity. Mean canal separation, as opposed to canal size, was implicated as a primary factor affecting age-related fluid dynamics. Future investigations through refinement of the model may implicate fluid stasis or inadequate nutrient transport experienced by osteocytes as a key factor in the initiation of cortical remodelling events.


Assuntos
Líquidos Corporais/fisiologia , Osso e Ossos/fisiologia , Osso e Ossos/ultraestrutura , Modelos Biológicos , Simulação por Computador , Humanos , Porosidade , Pressão
6.
J Am Coll Cardiol ; 24(6): 1475-81, 1994 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7930278

RESUMO

OBJECTIVES: This study was designed to determine the effectiveness, safety and costs associated with reuse of angioplasty catheters and to compare these results with those of a contemporary center that employed a single-use strategy. BACKGROUND: Coronary angioplasty is an important but expensive procedure. To overcome the financial constraints of the Canadian health care system, reuse of angioplasty catheters is routinely practiced in some institutions. METHODS: In a prospective observational study, data forms were completed after each angioplasty procedure and before patient discharge over a 10-month period. RESULTS: A total of 693 patients underwent coronary angioplasty in the two centers. Clinical and lesion characteristics were similar except for a higher incidence of unstable angina at the reuse center (p < 0.005). The angiographic success rate was identical (88%) at both centers. The reuse center utilized more balloon catheters/lesion (mean +/- SD 2.4 +/- 1.5 vs. 1.2 +/- 0.5, p < 0.00001) and had a higher incidence of initial balloon failure (10.2% vs. 3.3%, p < 0.0001). Significant prolongation of the procedure time (81 +/- 41 vs. 68 +/- 32 min, p < 0.0001) and increased volume of contrast medium (201 +/- 86 vs. 165 +/- 61 ml, p < 0.0001) were seen in the reuse center. A higher rate of adverse clinical events (7.8% vs. 3.8%, p < 0.025) was observed in the reuse center, especially in patients with unstable angina. CONCLUSIONS: The reuse strategy was associated with a higher rate of adverse events, prolonged procedure time and increased use of contrast medium, especially in lesions that were not crossed by the initial balloon and in patients with unstable angina. Whether these differences are related to the reuse strategy or to differences in patient groups cannot be ascertained by this observational study. A multicenter randomized trial is required to further assess the safety and the cost/benefit ratio of this strategy.


Assuntos
Angioplastia Coronária com Balão/economia , Angioplastia Coronária com Balão/instrumentação , Redução de Custos , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Reutilização de Equipamento/economia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
7.
J Am Coll Cardiol ; 35(3): 592-9, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10716459

RESUMO

OBJECTIVES: Our intent was to investigate the effect of the dihydropyridine calcium channel blocker amlodipine on restenosis and clinical outcome in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Amlodipine has sustained vasodilatory effects and relieves coronary spasm, which may reduce luminal loss and clinical complications after PTCA. METHODS: In a prospective, double-blind design, 635 patients were randomized to 10 mg of amlodipine or placebo. Pretreatment with the study drug started two weeks before PTCA and continued until four months after PTCA. The primary angiographic end point was loss in minimal lumen diameter (MLD) from post-PTCA to follow-up, as assessed by quantitative coronary angiography (QCA). Clinical end points were death, myocardial infarction, coronary artery bypass graft surgery and repeat PTCA (major adverse clinical events). RESULTS: Angioplasty was performed in 585 patients (92.1%); 91 patients (15.6%) had coronary stents implanted. Follow-up angiography suitable for QCA analysis was done in 236 patients in the amlodipine group and 215 patients in the placebo group (per-protocol group). The mean loss in MLD was 0.30 +/- 0.45 mm in the amlodipine group versus 0.29 +/- 0.49 mm in the placebo group (p = 0.84). The need for repeat PTCA was significantly lower in the amlodipine versus the placebo group (10 [3.1%] vs. 23 patients [7.3%], p = 0.02, relative risk ratio [RR]: 0.45, 95% confidence interval [CI]: 0.22 to 0.91), and the composite incidence of clinical events (30 [9.4%] vs. 46 patients (14.5%), p = 0.049, RR: 0.65, CI: 0.43 to 0.99) within the four months follow-up period (intention-to-treat analysis). CONCLUSIONS: Amlodipine therapy starting two weeks before PTCA did not reduce luminal loss, but the incidence of repeat PTCA and the composite major adverse clinical events were significantly reduced during the four-month follow-up period after PTCA with amlodipine as compared with placebo.


Assuntos
Anlodipino/uso terapêutico , Angioplastia Coronária com Balão , Bloqueadores dos Canais de Cálcio/uso terapêutico , Doença das Coronárias/terapia , Vasos Coronários/efeitos dos fármacos , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prevenção Secundária , Resultado do Tratamento
8.
Plant Foods Hum Nutr ; 38(4): 343-53, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3237636

RESUMO

The objective of this work was to study the effect of the extraction of phenols by methanol/acetone/water and proteolysis (pepsin 1 hour; trypsin 2 hours) on the nutritional characteristics of unheated rapeseed protein as measured by weight gain, protein intake, net protein ratio, apparent digestibility and absorbed protein. The effect of proteolysis of the methanol/acetone/water extracted rapeseed protein, and the effect of mixing the methanol/acetone/water extract back with the extracted rapeseed protein was also studied. Extraction of phenolic compounds from rapeseed flour significantly improved weight gain, protein intake, net protein ratio and absorbed protein value. However, the mixing of phenolic extract with the extracted rapeseed protein did not appear to have a significant effect. Enzymatic hydrolysis (1 hour with pepsin and 2 hours with trypsin) of the raw material significantly improved the weight gain and protein intake. The combined methanol/acetone/water extraction and protein hydrolysis treatments were beneficial on all nutritional quality parameters of rapeseed protein. These results suggest that the protein-bound phenolic compounds, rather than the free phenolic compounds contribute mainly to the decrease in the nutritional values of proteins associated with phenolic compounds in raw flour before extraction.


Assuntos
Brassica/análise , Proteínas de Plantas/análise , Acetona , Animais , Interpretação Estatística de Dados , Hidrólise , Metanol , Valor Nutritivo , Fenóis , Ratos , Ratos Endogâmicos
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