RESUMEN
This study aimed to explore the effects of "touch-rugby" training on the cardiovascular autonomic control in sedentary subjects. 22 adults (30-64 years old) were included in this study. Before (pre-test) and after (post-test) the period of training, cardio-respiratory recordings were achieved at rest and during a graded maximal exercise on a treadmill. The Smoothed-Pseudo-Wigner-Ville Distribution provided instantaneous time frequency components of RR intervals and systolic blood pressure variability in low- and high-frequency bands. The baroreflex sensitivity was assessed in low-frequency and high-frequency bands. Between pre-test and post-test, resting heart rate (74±10 vs. 69±12 beats.min(-1), p<0.05) and systolic blood pressure (118±19 vs. 103±22 mm Hg, p<0.01) decreased. Root mean square of successive differences (34.6±30.1 vs. 47.6±34.8 ms, p<0.001), high-frequency RR variability (590±288 vs. 1262±767 ms², p<0.001) increased whereas low-frequency/high-frequency ratio decreased (3.5±3.4 vs. 1.5±0.9, p<0.05). The high-frequency baroreflex sensitivity increased (13.4±10.1 vs. 26.0±20.9 ms.mmHg(-1), p<0.05). Playing touch rugby with one session weekly over 3 months modified the cardiovascular autonomic control of sedentary subjects. A decrease in the sympathetic tone combined with both an increase in the vagal tone and a decrease in systolic blood pressure at rest were observed. Therefore, such training appears to be beneficial to cardiac health.
Asunto(s)
Sistema Nervioso Autónomo/fisiología , Presión Sanguínea/fisiología , Ejercicio Físico/fisiología , Fútbol Americano/fisiología , Adulto , Barorreflejo/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Descanso/fisiologíaRESUMEN
Mutations associated with hepatitis B virus (HBV) resistance to lamivudine have not been extensively addressed in human immunodeficiency virus (HIV)-HBV coinfection. We have studied the HBV polymerase sequences from nine coinfected patients who experienced HBV recurrence while under lamivudine treatment. In seven of these nine patients, Met(550), belonging to the highly conserved YMDD motif, was mutated to Val and was associated with a substitution of Met for Leu(526) in each case. In the two remaining patients, we found a Met(550)-to-Ile change that was associated in only one case with a Leu(526)-to-Met mutation. No mutation was observed in three control patients not receiving lamivudine. This study demonstrates the emergence of particular genetic profiles in HBV-HIV-coinfected patients experiencing a loss of control of HBV infection despite high doses of lamivudine.
Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Virus de la Hepatitis B/genética , Hepatitis B/tratamiento farmacológico , Lamivudine/uso terapéutico , Mutación , Farmacorresistencia Microbiana , Infecciones por VIH/complicaciones , Hepatitis B/complicaciones , Virus de la Hepatitis B/efectos de los fármacos , HumanosRESUMEN
OBJECTIVE: The diagnosis of perioperative myocardial infarction (PMI) after cardiac surgery remains an important issue. The present study was designed to determine the relevance of the measurement of serum cardiac troponin I (cTnI, a biochemical marker with high cardiospecificity. Therefore, cTnI was compared with creatine kinase-MB (CK-MB) mass and to the other classical signs of myocardial infarction after cardiac surgery. DESIGN: A prospective study. SETTING: A university hospital. PARTICIPANTS: Forty-one patients undergoing coronary artery bypass grafting (CABG) (n = 17) or valvular replacement (n = 24). These patients were separated into three groups according to postoperative complications: group 1, Q-wave PMI (n = 5); group 2, nonspecific changes (non-Q wave) on the electrocardiogram (ECG) and/or need of inotropic support (n = 12); group 3, no postoperative complication (n = 24). INTERVENTIONS: Postoperative follow-up consisted of serial determination of different biochemical markers (CK, CK-MB, cTnI), ECGs, and echocardiography. Blood samples were drawn before (H0) and 3 (H3), 12 (H12), 20 (H20), 24 (H24), and 48 (H48) hours after the onset of cardiopulmonary bypass (CPB). MEASUREMENTS AND MAIN RESULTS: In all patients in group 3, CK-MB and cTnI concentrations increased, and peaked at H12 after CPB (13.4 +/- 7.7 and 7.1 +/- 4.1 micrograms/L for CK-MB and cTnI, respectively). In group 1, cTnI concentrations were significantly higher than in group 3 from H12 until H48 (p < 0.002), peaked later (H24; 59.0 +/- 38.8 micrograms/L), and remained in plateau. In group 2, cTnI peak concentrations were significantly different than in groups 1 and 3 (26.2 +/- 14.8 micrograms/L) and occurred at H24 (as in patients with Q-wave PMI). CONCLUSION: A cTnI concentration less than 15 micrograms/L (mean + 2 standard deviations [SDs] of peak cTnI in group 3) within 24 to 48 hours after cardiac surgery is highly suggestive of the absence of perioperative myocardial necrosis. Because of its higher cardiospecificity than CK-MB mass, and its prolonged release after myocardial necrosis, cTnI might be a useful tool in the diagnosis of PMI after cardiac surgery.