RESUMEN
The purpose of this study was to investigate the relationship between the changes in mean skin temperature and the energy expenditure induced by drinking coffee containing 4 mg of caffeine/kg body weight. Twelve healthy, weight-stable subjects were studied (five males, seven females; mean age +/- s.d., 25.3 +/- 3.3 years; BMI 22.5 +/- 3.1). Energy expenditure (EE) was measured by open-circuit indirect calorimetry, and skin temperature was determined with thermometric probes applied to the four body regions indicated by Ramanathan (chest, arm, thigh, calf). The calorimetric and thermometric measurements were carried out for 120 min with the participants lying down quietly. A significant correlation was found between the total thermogenic responses (net responses) and the temperature changes between 90 and 120 min from the coffee intake. Multiple regression analysis using mean EE after coffee intake as the dependent variable, and mean skin temperature and body weight as the independent variables yields the following equation: EE (kcal/min/m2) = -1.44 + 0.052 (mean skin temperature) + 0.004 (body weight). (r = 0.71 and P = 0.01) Our results indicate that small interindividual differences in mean skin temperature could explain energy expenditure differences in subjects with the same body weight, body composition and physical activity. This, in turn, could help explain variations in proneness to obesity.
Asunto(s)
Regulación de la Temperatura Corporal/efectos de los fármacos , Cafeína/farmacología , Café , Temperatura Cutánea/efectos de los fármacos , Adulto , Peso Corporal , Cafeína/administración & dosificación , Calorimetría Indirecta , Metabolismo Energético/efectos de los fármacos , Femenino , Humanos , Cinética , Masculino , Análisis de RegresiónRESUMEN
Taurine is a non-protein sulfur amino acid widely distributed in mammalian tissues, with poorly understood functions. Taurine administration has a variety of hemodynamic effects, including improvement of cardiac function and suppression of sympathetic activity. Increased urinary volume and sodium excretion have been reported in taurine-fed hamsters. Since patients with ascitic liver cirrhosis have severe hemodynamic and renal abnormalities potentially sensitive to taurine feeding, we evaluated the effects of the i.v. infusion of taurine on urinary flow and sodium excretion and on the hormones involved in the control of hydrosaline homeostasis. Eight cirrhotic patients with tense ascites were given an i.v. bolus of taurine (16 mumoles in 40 ml of saline). The next day patients were given saline only, as a control. Diuresis, urinary sodium and plasma renin activity, aldosterone, atrial natriuretic peptide and arginine vasopressin were measured for the following 6 hrs. Plasma taurine increased ten fold after infusion, then decreased exponentially. No side effects were recorded. After taurine, but not after saline, there was a prompt and significant increase in both urinary volume and sodium excretion. Diuresis increased from 340 +/- 43 to 817 +/- 116 microliters/min (p < 0.01); urinary sodium from 13.8 +/- 3 to 26.3 +/- 4 mumoles/min (p < 0.05). Both values returned to normal after 2-3 hrs. Taurine infusion caused a concomitant significant decrease in plasma renin activity (from 7.7 +/- 2.2 to 4.3 +/- 1.9 ng/ml/hr, p < 0.05) and aldosterone (from 588 +/- 47 to 348 +/- 89 pg/ml, p < 0.05), but no changes in atrial natriuretic peptide and arginine vasopressin. We conclude that i.v. taurine infusion in ascitic cirrhosis promotes a transient diuresis and natriuresis, apparently through the inhibition of the renin-aldosterone axis.
Asunto(s)
Diuresis/efectos de los fármacos , Cirrosis Hepática Alcohólica/orina , Cirrosis Hepática/orina , Natriuresis/efectos de los fármacos , Taurina/farmacología , Adulto , Anciano , Aldosterona/sangre , Arginina Vasopresina/sangre , Ascitis , Factor Natriurético Atrial/sangre , Presión Sanguínea/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Infusiones Intravenosas , Cirrosis Hepática/sangre , Cirrosis Hepática/fisiopatología , Cirrosis Hepática Alcohólica/sangre , Cirrosis Hepática Alcohólica/fisiopatología , Masculino , Persona de Mediana Edad , Valores de Referencia , Renina/sangre , Sodio/orina , Taurina/administración & dosificación , Taurina/sangre , Factores de TiempoRESUMEN
A total of 1552 antepartum nonstress tests performed during the week before delivery are analyzed with respect to both reactivity and the presence of pathologic baseline patterns (tachycardia, bradycardia, diminished beat-to-beat variability) or decelerations. Correlation with mode of delivery and condition of the newborn infant shows that, irrespective of nonstress test reactivity, the presence of baseline anomalies and/or decelerations is associated with significantly increased perinatal morbidity and mortality. Nonstress test analysis, if systematic, that is, not restricted to reactivity alone, makes it possible to better detect fetuses at high perinatal risk, in which case closer surveillance would be indicated.
Asunto(s)
Corazón Fetal/fisiología , Monitoreo Fetal/métodos , Frecuencia Cardíaca , Diagnóstico Prenatal , Puntaje de Apgar , Parto Obstétrico , Femenino , Sufrimiento Fetal/epidemiología , Humanos , Mortalidad Infantil , Recién Nacido , Embarazo , RiesgoRESUMEN
A Listeria infection of a twin pregnancy had induced a partus immaturus at 23 weeks. One foetus died in utero of a widespread foeto-placental granulomatosis, while the other one, dying sub-partu, showed only retroplacental abcesses. The unequal extent of the infection in the two placentas -- of diamniotic, dichorionic type -- is interpreted as different stages of the same disease; it could be due to a different resistance to the germ between the two dizygotic foetuses.