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Evaluation of microvascular endothelial function is essential for investigating the pathophysiology and treatment of cardiovascular and metabolic diseases. Although laser speckle contrast imaging technology is well accepted as a noninvasive methodology for assessing microvascular endothelial function, it has never been used to compare male patients with coronary artery disease with male age-matched healthy controls. Thus, the aim of this study was to determine whether laser speckle contrast imaging could be used to detect differences in the systemic microvascular functions of patients with established cardiovascular disease (n=61) and healthy age-matched subjects (n=24). Cutaneous blood flow was assessed in the skin of the forearm using laser speckle contrast imaging coupled with the transdermal iontophoretic delivery of acetylcholine and post-occlusive reactive hyperemia. The maximum increase in skin blood flow induced by acetylcholine was significantly reduced in the cardiovascular disease patients compared with the control subjects (74 vs 116%; P<0.01). With regard to post-occlusive reactive hyperemia-induced vasodilation, the patients also presented reduced responses compared to the controls (0.42±0.15 vs 0.50±0.13 APU/mmHg; P=0.04). In conclusion, laser speckle contrast imaging can identify endothelial and microvascular dysfunctions in male individuals with cardiovascular disease. Thus, this technology appears to be an efficient non-invasive technique for evaluating systemic microvascular and endothelial functions, which could be valuable as a peripheral marker of atherothrombotic diseases in men.

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This study compared strategies to equalize the volume of aerobic exercise performed with different intensities by Wistar rats, based on the distance covered during exercise bouts and energy expenditure (EE, isocaloric sessions) obtained from oxygen uptake (V̇O2) or respiratory exchange ratio (RER). Thirty-three male rats (270.5±12.8 g) underwent maximal exercise tests to determine V̇O2 reserve (V̇O2R), being randomly assigned to three groups: moderate-intensity continuous exercise at speed corresponding to 50% V̇O2R (MIC; n=11); high-intensity continuous exercise at 80% V̇O2R (HIC; n=11); and high-intensity intermittent exercise (HII; n=11) at 60% V̇O2R (3 min) and 80% V̇O2R (4 min). Exercise duration was calculated individually to elicit EE of 5 kcal in each session. No difference between groups was found for total running distance (MIC: 801±46, HIC: 734±42, HII: 885±64 m; P=0.13). Total EE measured by RER was systematically underestimated compared to values obtained from V̇O2 (HII: 4.5% and MIC: 6.2%, P<0.05). Total EE (calculated from V̇O2), and duration of HIC bouts (2.8 kcal and 30.8±2.2 min) were lower (P<0.0001) than in MIC (4.9 kcal and 64.7±1.8 min) and HII (4.7 kcal and 46.9±2.2 min). Predicted and actual values of total V̇O2, total EE, and duration of isocaloric sessions were similar in MIC and HII (P>0.05), which were both higher than in HIC (P<0.0001). In conclusion, the time to achieve a given EE in exercise bouts with different intensities did not correspond to the total distance. Therefore, the volume of aerobic exercise in protocols involving Wistar rats should be equalized using EE rather than total covered distance.

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This study compared strategies to equalize the volume of aerobic exercise performed with different intensities by Wistar rats, based on the distance covered during exercise bouts and energy expenditure (EE, isocaloric sessions) obtained from oxygen uptake (V̇O2) or respiratory exchange ratio (RER). Thirty-three male rats (270.5±12.8 g) underwent maximal exercise tests to determine V̇O2 reserve (V̇O2R), being randomly assigned to three groups: moderate-intensity continuous exercise at speed corresponding to 50% V̇O2R (MIC; n=11); high-intensity continuous exercise at 80% V̇O2R (HIC; n=11); and high-intensity intermittent exercise (HII; n=11) at 60% V̇O2R (3 min) and 80% V̇O2R (4 min). Exercise duration was calculated individually to elicit EE of 5 kcal in each session. No difference between groups was found for total running distance (MIC: 801±46, HIC: 734±42, HII: 885±64 m; P=0.13). Total EE measured by RER was systematically underestimated compared to values obtained from V̇O2 (HII: 4.5% and MIC: 6.2%, P<0.05). Total EE (calculated from V̇O2), and duration of HIC bouts (2.8 kcal and 30.8±2.2 min) were lower (P<0.0001) than in MIC (4.9 kcal and 64.7±1.8 min) and HII (4.7 kcal and 46.9±2.2 min). Predicted and actual values of total V̇O2, total EE, and duration of isocaloric sessions were similar in MIC and HII (P>0.05), which were both higher than in HIC (P<0.0001). In conclusion, the time to achieve a given EE in exercise bouts with different intensities did not correspond to the total distance. Therefore, the volume of aerobic exercise in protocols involving Wistar rats should be equalized using EE rather than total covered distance.

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BACKGROUND AND OBJECTIVES: Platelet transfusions are performed almost entirely according to expert experience. This study assessed the effectiveness of a restrictive guideline to reduce platelet transfusions in preterm infants. METHODS: A retrospective cohort of preterm infants with a birth weight of <1500 g had been born in 2 periods. In Period 1, a transfusion was indicated for a platelet count of <50,000/ml in clinically stable neonates or <100,000/ml in bleeding or clinically unstable infants. In Period 2, the indications were restricted to <25,000/ml in clinically stable neonates, or <50,000/ml in newborns who were either on mechanical ventilation, subject to imminent invasive procedures, within 72 h following a seizure, or extremely premature and <7 days old. A count of <100,000/ml was indicated for bleeding or major surgery. RESULTS: Periods 1 and 2 comprised 121 and 134 neonates, respectively. The rates of ventricular haemorrhage and intrahospital death were similar in both periods. The percentage of transfused infants, the odds of receiving a platelet transfusion, the mean platelet count before transfusion and the percentage of transfusions with a platelet count >50,000/ml were greater in Period 1. Among thrombocytopenic neonates, the percentage of transfused neonates and the number of transfusions were similar in both groups. CONCLUSION: The restrictive guideline for platelet transfusions reduced the platelet count thresholds for neonatal transfusions without increasing the rate of ventricular haemorrhage.

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AIM: Exercise effects in subjects with HIV/AIDS are not entirely understood. The study aimed to investigate the effects of a supervised exercise program on the physical fitness and immunological function of HIV-infected subjects. METHODS: Twenty-seven highly active antiretroviral therapy treated HIV-infected patients (age: 45±2 years; CD4-T: 21.3±2.2%) were assigned to a control (CG, n=8) or experimental (EG, n=19) group. The EG participated in a 12-week exercise program, consisting of aerobic training, strength, and flexibility exercises (3 times/wk; aerobic-30min: PWC 150; strength-50min: 3 sets of 12 reps of 5 exercises at 60-80% 12 RM; flexibility-10min: 2 sets of 30 s at maximal range of motion of 8 exercises). RESULTS: Prior to training there was no significant difference in any variable between the EG and the CG. Flexibility (23%, P<0.05), 12 repetition maximum in the leg press and seated bilateral row exercises (54% and 65% respectively, P<0.05) increased, while the heart rate at a given cycle ergometer workload declined (19% for slope and 12% for intercept, P<0.05) in the EG, but not in the CG. No significant differences were found for the relative and absolute CD4 T-cell counts between groups prior to or after training, but there was a slight enhancement trend in the EG (16%, P=0.19). CONCLUSION: Overall training can improve the muscle and aerobic fitness of HIV-infected patients with no negative effect on their immunological function.

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Diversos estudos relatam os efeitos da denervacao sobre a homeostasia energetica do musculo soleo, sendo demonstrado que concomitante ao processo de atrofia ha reducao no metabolismo muscular da glicose e aumento de colageno no endomisio e perimisio, indicando que a atrofia e acompanhada de alteracoes metabolicas e fibrose. O objetivo deste trabalho foi estudar os efeitos da associacao dos tratamentos com metformina(0,1g/kg) e estimulacao eletrica (f=10Hz, fase=3ms, 20 min/dia) sobre a morfologia e reserva de glicogenio do musculo soleo denervado de ratos. Tratamento com PAS (acido periodico de Schift) foi utilizado para evidenciar reservas de glicogenio, e a densidade de areas das fibras foi obtida pela tecnica morfometrica e analisada pela ANOVA com teste F e teste de Tukey para comparacao das medias. Apos 15 dias, a associacao dos tratemntos nao recuperou o peso do musculo soleo (69,33mg), perdido com a denervacao (63,33mg, p>0,05), no entanto, promoveu aumento de granulos de glicogenio, evidenciando melhora nas condicoes metabolicas das fibras

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