RESUMEN
OBJECTIVE: To report the proportion of Canadian medical students interested in a career in psychiatry at medical school entry and to describe the unique demographics and career influences associated with this early interest. METHODS: From 2001 to 2004, during the first 2 weeks of medical school, a 41-item survey of career choice, demographics, and attitudes toward various aspects of medical practice was distributed to all students in 18 classes at 8 Canadian medical schools. Associations between early career interest, demographics, and career influences were explored. RESULTS: Of the 2096 completed surveys, 3.2% of students named psychiatry as their first career choice. While 34% of students considered psychiatry a possible career option, 54.9% stated that they had not considered this option. Students interested in psychiatry were more likely than other students to have an undergraduate education in the arts, to have close family or friends practicing medicine, and to have worked voluntarily with people with mental illness. Students interested in psychiatry had a lesser social orientation than students interested in family medicine but had a greater social orientation and lesser hospital orientation than students interested in other specialties. CONCLUSIONS: Enhanced psychiatric care may be aided by the selective recruitment into medical school of students with a demonstrated empathy toward people with mental illness, an educational background in the arts, and a strong social orientation. As career influences change throughout medical school, participants in this study will be re-surveyed at graduation to better understand the evolution of career choice decision-making throughout medical school.
Asunto(s)
Selección de Profesión , Psiquiatría/educación , Actitud del Personal de Salud , Canadá , Recolección de Datos , Humanos , Internado y Residencia , Estudiantes de Medicina/psicología , Estudiantes de Medicina/estadística & datos numéricosRESUMEN
This study compared the effects of inspiring either a hyperoxic (60% O(2)) or normoxic gas (21% O(2)) while cycling at 70% peak O(2) uptake on 1) the ATP derived from substrate phosphorylation during the initial minute of exercise, as estimated from phosphocreatine degradation and lactate accumulation, and 2) the reliance on carbohydrate utilization and oxidation during steady-state cycling, as estimated from net muscle glycogen use and the activity of pyruvate dehydrogenase (PDH) in the active form (PDH(a)), respectively. We hypothesized that 60% O(2) would decrease substrate phosphorylation at the onset of exercise and that it would not affect steady-state exercise PDH activity, and therefore muscle carbohydrate oxidation would be unaltered. Ten active male subjects cycled for 15 min on two occasions while inspiring 21% or 60% O(2), balance N(2). Blood was obtained throughout and skeletal muscle biopsies were sampled at rest and 1 and 15 min of exercise in each trial. The ATP derived from substrate-level phosphorylation during the initial minute of exercise was unaffected by hyperoxia (21%: 52.2 +/- 11.1; 60%: 54.0 +/- 9.5 mmol ATP/kg dry wt). Net glycogen breakdown during 15 min of cycling was reduced during the 60% O(2) trial vs. 21% O(2) (192.7 +/- 25.3 vs. 138.6 +/- 16.8 mmol glycosyl units/kg dry wt). Hyperoxia had no effect on PDH(a), because it was similar to the 21% O(2) trial at rest and during exercise (21%: 2.20 +/- 0.26; 60%: 2.25 +/- 0.30 mmol.kg wet wt(-1).min(-1)). Blood lactate was lower (6.4 +/- 1.0 vs. 8.9 +/- 1.0 mM) at 15 min of exercise and net muscle lactate accumulation was reduced from 1 to 15 min of exercise in the 60% O(2) trial compared with 21% (8.6 +/- 5.1 vs. 27.3 +/- 5.8 mmol/kg dry wt). We concluded that O(2) availability did not limit oxidative phosphorylation in the initial minute of the normoxic trial, because substrate phosphorylation was unaffected by hyperoxia. Muscle glycogenolysis was reduced by hyperoxia during steady-state exercise, but carbohydrate oxidation (PDH(a)) was unaffected. This closer match between pyruvate production and oxidation during hyperoxia resulted in decreased muscle and blood lactate accumulation. The mechanism responsible for the decreased muscle glycogenolysis during hyperoxia in the present study is not clear.
Asunto(s)
Metabolismo de los Hidratos de Carbono , Hiperoxia/fisiopatología , Ácido Láctico/metabolismo , Músculo Esquelético/fisiopatología , Oxígeno/metabolismo , Esfuerzo Físico , Complejo Piruvato Deshidrogenasa/sangre , Adulto , Prueba de Esfuerzo , Humanos , Masculino , Consumo de Oxígeno , Método Simple Ciego , Factores de TiempoRESUMEN
This study investigated whether the supplement Microhydrin (MH) contains silica hydride bonds (Si-H) and if Microhydrin supplementation increased performance or altered metabolism compared to placebo (PL) during prolonged endurance cycling. Seven endurance-trained male cyclists consumed 9.6 g of MH or PL over 48 h in a randomized, double-blind, crossover design. Subjects cycled at approximately 70% of their VO2peak, coupled with five 2-min bursts at 85% VO2peak to simulate hill climbs over 2 h. Subjects then completed a time trial, which required them to complete 7 kJ/kg body mass as quickly as possible. Infrared spectrometry analysis showed a complete absence of Si-H bonds in MH. There was no difference in time trial performance between the 2 trials (PL: 2257+/-120 s vs. MH: 2345+/-152 s). Measured oxygen uptake, respiratory exchange ratio, carbohydrate (MH: 2.99+/-0.13 g/min; PL: 2.83+/-0.17 g/min avg. over 2 h) and fat (MH: 0.341+/-0.06 g/min; PL: 0.361+/-0.07 g/min) oxidation rates and all blood parameters (lactate, glucose, and free fatty acids) were all unaffected by MH supplementation. The volume of expired CO2 and ventilation were significantly greater with MH supplementation (P < or = 0.05). The results indicate that oral Microhydrin supplementation does not enhance cycling time trial performance or alter metabolism during prolonged submaximal exercise in endurance-trained cyclists.