Plasma zinc concentration, body composition and physical activity in obese preschool children.

Zinc (Zn) deficiency and obesity can be observed together in some developing countries. Zn deficiency may enhance fat deposition and decrease lean mass accrual, which in turn, appears to influence physical activity (PA), although this has not yet been evaluated in obese children. The objective of the study was to find out the association between measurements of plasma Zn and serum leptin, body composition, and PA in Chilean obese preschool children. Seventy-two 18- to 36-month-old obese children [weight-for-length/height z score (WHZ) > 2.0 SD], belonging to low socioeconomic communities, participated in the study. Plasma Zn, serum leptin, weight, waist circumference, height, total body water (TBW) assessed by deuterium isotopic dilution technique and daily activity, measured by registering 48 h with an accelerometer, were evaluated. We found 82% of children with WHZ > 3 SD. The geometric mean Zn intake was 6.2 +/- 2.5 mg/day. The mean plasma Zn was 91.8 +/- 11.4 microg/dL, with 10% of the children having levels <80 microg/dL. No correlation was found between plasma Zn concentrations and either weight, WHZ, or waist circumference. Serum leptin was lower in males than in females (2.9 +/- 2.8 vs 6.8 +/- 5.0 ng/mL, respectively; p < 0.001). TBW was different between males and females (56.2 +/- 5.4 vs 52.8 +/- 4.3% body weight, respectively; p = 0.004), but no significant association was found between TBW and plasma Zn. Moderate + intense PA, (as percentage of wake time), was greater in males than in females (6.3 +/- 3.1% vs 3.4 +/- 2.3%, respectively; p < 0.001), but it was not significantly correlated to plasma Zn. In conclusion, plasma Zn was not associated with body composition as assessed by TBW, serum leptin, or with the magnitude of physical activity in Chilean overweight preschool children.

[Cardiac rhythm and systemic embolism in long-term follow up of patients with non-valvular paroxysmal atrial fibrillation]. / Ritmo cardíaco y embolias sistémicas en la evolución alejada de pacientes con fibrilación auricular paroxística no valvular.

BACKGROUND: Paroxysmal atrial fibrillation may predispose to systemic embolism. There is little information about the evolution of cardiac rhythm and the occurrence of new embolic events in these patients. AIM: To report the results of a long term follow up of patients with paroxysmal atrial fibrillation. PATIENTS AND METHODS: Patients consulting for non valvular paroxysmal atrial fibrillation were followed for a mean period of 5 years. An EKG, 2D echocardiogram and brain CT scans were performed on admission and at the end of the follow up period to all patients. RESULTS: Sixty eight patients aged 65 +/- 1.5 years were studied. Thirty two had an idiopathic atrial fibrillation, 28 had a history of mild hypertension and 8 had a history of coronary artery disease. Evidence of systemic emboli was found in 17 patients at entry (to the brain in 14 patients). During the follow up 87% of patients required antiarrhythmics, 27% were anticoagulated and 28% received aspirin. Five patients had new embolic episodes. Of these, four had a history of prior embolism. Forty one percent of patients continued in sinus rhythm and remained asymptomatic, 32% had at least one recurrence of paroxysmal atrial fibrillation and nine patients evolved to chronic atrial fibrillation. Five patients required a permanent pacemaker due to symptomatic bradycardia. CONCLUSIONS: Most patients with non valvular paroxysmal atrial fibrillation remain in sinus rhythm but one third have recurrences of the arrhythmia. A main risk factor for embolism is the history of previous embolic episodes.

[Idiopathic tachycardia originated in left ventricle]. / Taquicardia ventricular idiopática originada en el ventrículo izquierdo.

BACKGROUND: Idiopathic ventricular tachycardia occurs in patients with no structural heart disease and may originate in left of right ventricle. AIM: To report our experience with this condition. PATIENTS AND METHODS: We report six patients (five male), aged 35 years old as a mean, with idiopathic left ventricular tachycardia that were subjected to conventional electrophysiological studies with atrial and ventricular stimulation programs and radiofrequency fulguration, between December 1993 and May 1996. RESULTS: The mean lapse of disease was 24 months and five patients received antiarrhythmic medications previously. All tachycardias had a morphology with an image of right bundle branch block. Radiofrequency fulguration was done after obtaining a satisfactory pace mapping of at least 11 of the 12 superficial EKG derivations. The procedure was successful in five patients and two had a relapse. One of the relapsed patients was successfully fulgurated again. CONCLUSIONS: Radiofrequency fulguration for idiopathic ventricular tachycardias is a safe and effective therapeutic procedure.

[Cardiopulmonary exercise test in patients with chronic cardiac failure: comparison with normal subjects and reproducibility of measurements]. / Prueba de esfuerzo cardiopulmonar en pacientes con insuficiencia cardíaca crónica: comparación con sujetos normales y reproducibilidad de las mediciones.

The aim of this work was to measure oxygen consumption and carbon dioxide production during exercise in 21 subjects with cardiac failure and 13 normal subjects. During the resting period, subjects with cardiac failure had higher ventilatory frequency and respiratory quotient than normals. During maximal exercise, the former achieved higher ventilatory frequency and oxygen ventilatory equivalent than normals. In subjects with cardiac failure and normals, anaerobic thresholds were 14.4 +/- 0.9 and 28.8 +/- 2.2 ml/kg/min respectively and peak oxygen consumptions 17.1 +/- 1 and 34.4 +/- 1.7 ml/kg/min respectively. There were less than 10% differences in parameters when tests were repeated in 10 subjects with cardiac failure. It is concluded that gas exchange testing may be a reliable and objective assessment method in patients with cardiac failure.

Influence of blood storage after in vitro exposure on the yield of micronuclei observed in human lymphocytes.

In a cooperative study, four laboratories evaluated the micronucleus test in irradiated and non-irradiated lymphocytes with respect to time of storage, the difference between X-ray and gamma exposure and inter-observer variance. The results were compared with parallel studies on dicentric aberrations. No significant differences between laboratories, with respect to storage time or between gamma and X-irradiation were observed for micronuclei and dicentrics using analysis of variance. However, micronuclei are not suitable for an assessment of exposure inhomogeneity because of a significant overdispersion already in controls and homogeneously irradiated samples.

[Surgery of evolving myocardial infarction]. / Cirugía del infarto miocardico en evolución.

Limitation of infarct size has been proven to improve the prognosis in patients with recent myocardial infarction (MI). Emergency coronary bypass surgery may be used for this aim. We operated on 44 such patients within 15 days of onset of MI. Operation was done within 6 hr in 11 patients and later on in the other 33, due to post infarction angina or incomplete MI. One patient died in the perioperative period. Thirty nine patients were followed at a mean of 33 months: 2 have angina, one dyspnea and the rest is asymptomatic. We believe that bypass surgery is an effective treatment in selected patients with recent MI.