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In an effort to better understand the relationship existing between lipoprotein pattern and longevity, we studied the lipid and lipoprotein distribution of 94 men over age 80 who lived in a nursing home, and assessed the role of selective mortality, body mass and sex hormone secretion in determining these distributions. High density lipoprotein subfraction and serum testosterone measurements were obtained on subsamples. The main findings were: (a) Presence of a lipoprotein pattern characterized by low LDL (total serum cholesterol: 179.6 +/- 36.0 mg/dl; LDL cholesterol: 106.3 +/- 31.2 mg/dl) and high HDL2 cholesterol (18.5 +/- 10.2 mg/dl) levels. (b) Occurrence of a positive association between LDL and HDL3 (r = 0.51, P less than 0.01), resulting in an overall high HDL2/HDL3 ratio. Mortality over a 6-month period was directly related to LDL level and possibly inversely related to HDL2 level, suggesting that selective mortality played a major role in determining the pattern observed. Body mass and serum testosterone concentration, which tended to be low, were independently correlated with lipoprotein level; a particularly strong correlation (positive) existed between free testosterone and triglyceride (r = 0.68, P less than 0.01). The latter results suggest that changes related to senescence also influenced lipid and lipoprotein levels.

This study was undertaken to compare prospectively the frequency, nature, and severity of infections experienced by children in three types of child care arrangements: home care, group care (two to six children), and day care (seven or more children). Children were enrolled at birth and observed for 12 to 18 months. At entry there were 159 children in home care, 40 in group care, and 45 in day care. The families were telephoned every 2 weeks to record on a standardized form the type and severity of illnesses experienced during the previous interval. Severe illnesses were defined by high fever, duration exceeding 10 days, or physician visit. Children remaining in their original child care group for at least 1 year were compared with regard to the frequency and severity of illness. Children in group care and day care were more likely than children in home care to experience at least six respiratory infections, more than 60 days of illness, and more than four severe illnesses (P less than 0.01). Similarly, life table analyses showed that children in home care had fewer episodes of infection than did children in day care (P less than 0.01). Although no children were hospitalized because of acute infections during the first year of study, hospitalization for myringotomy and tube placement occurred in 21% of children in day care and 3% of children in home care (P less than 0.01).

An epidemiological link was found between contamination of a hospital water-supply by Legionella pneumophila and by Pittsburgh pneumonia agent (PPA) and subsequent cases of nosocomial legionnaires' disease and Pittsburgh pneumonia. The extent of L pneumophila isolation from the water-supply paralleled the occurrence of disease. Whenever L pneumophila was isolated from more than 30% of ten selected water sites, nosocomial legionellosis occurred. The temperature of the hot water tanks was raised to 60-77°C for 72 h, and water outlets were flushed for 30 min with hot water. A decline in numbers of L pneumophila and PPA in the water-supply was followed by a fall in the incidence of legionnaires' disease and Pittsburgh pneumonia. In addition, intermittent raising of the temperature in the hot water system decreased both the number of months in which disease occurred and the proportion of nosocomial pneumonias caused by these organisms.

The ability of exogenously administered N6, O2′-dibutyryl analogue of cyclic AMP to shorten, in a dose-related manner, the duration of narcosis of eight structurally different agents (chloral hydrate, paraldehyde, diazepam, amobarbital, halothane, ketamine, ethanol and methanol) has been demonstrated in the rat. No other nucleotide, neurotransmitter, biogenic amine or hormone tested, shortened, in a dose-related manner the sleeping time induced by the anaesthetic agents.

Three doses of amobarbital, an anesthetic dose (80 mg/kg), a minimum lethal dose (130 mg/kg), and a high lethal dose (180 mg/ kg) were administered intraperitoneally to groups of rats. All rats were injected intracerebroventricularly with 0.9% saline or dibutyryl cyclic AMP, 200 μg/rat. While those rats treated with saline solution were still sleeping at decapitation and those treated with dibutyryl cyclic AMP were awake, there were no significant differences in their brain concentrations of amobarbital.

The effect of incomplete penetrance of monofactorial recessive trait on the frequencies of sib-pair types in a random mating population has been examined. A method of estimating the gene frequency and the penetrance percentage from sib-pair data is given and illustrated by two numerical examples. The difficulty in interpreting the sib-pair data on rheumatoid arthritis in the Blackfeet Indians has been discussed.