Altitude acclimatization: influence on periodic breathing and chemoresponsiveness during sleep.

Although the influence of altitude acclimatization on respiration has been carefully studied, the associated changes in hypoxic and hypercapnic ventilatory responses are the subject of controversy with neither response being previously evaluated during sleep at altitude. Therefore, six healthy males were studied at sea level and on nights 1, 4, and 7 after arrival at altitude (14,110 ft). During wakefulness, ventilation and the ventilatory responses to hypoxia and hypercapnia were determined on each occasion.

Acute myocardial effects of chloramphenicol in newborn pigs: a possible insight into the gray baby syndrome.

Mechanical function and mitochondrial respiration were observed in newborn pig hearts in the presence of chloramphenicol. Isolated perfused hearts exposed to chloramphenicol (25, 50, or 100 micrograms/ml) demonstrated acute reductions in pressure development and cardiac output accompanied by elevated left atrial filling pressure. The effects of chloramphenicol and chloramphenicol succinate (25, 50, 100, or 200 micrograms/ml) on oxidative activity of isolated mitochondria were also investigated.