Chronic toxicity of dietary 2,3,7,8-tetrachlorodibenzo-p-dioxin to mink.

Mature female natural dark mink (Mustela vison) were fed 0.0006 (control), 0.016, 0.053, 0.180, or 1.40 ppb 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for 131-132 d to ascertain the chronic toxic effects of TCDD in mink, including reproduction. Consumption of the 1.4 ppb TCDD diet resulted in lethargy, bloody stools, and 16.7% mortality. Final mink body weights were inversely proportional to the dietary TCDD concentrations. Due to subnormal mink breeding, definitive effects of TCDD on mink reproductive performance were not ascertained; however, there were significant dose-dependent decreases in kit (young mink) birth weight and survival from birth to 3 w of age in the groups that had reproduction. There were also significant differences in adult minkwhite blood cell counts, plasma total solids, serum iron, phosphorus, albumin, total protein, total CO2, cholesterol, osmolality, and anion gap concentrations, and alanine aminotransaminase activity between the various dietary groups. During the latter stages alopecia and thickened, deformed, and elongated toenails were observed in the adult mink fed 1.4 ppb TCDD. At termination the mink fed 1.4 ppb TCDD had ascites, gastric ulcers, intestinal hemorrhages, depletion of adipose tissue, and mottled and/or discolored livers, spleens, and kidneys. Focal lymphocytic meningitis in region of the olfactory bulb was present in 42% of the mink fed 1.4 ppb TCDD. These results confirmed the high sensitivity of mink to TCDD and revealed a toenail abnormality not previously reported for mink fed TCDD.

The health development organization: an organizational approach to achieving child health development.

The health development organization (HDO) is a new approach to the organization and delivery of children's health and social services. The HDO would combine the best features of vertically integrated HMOs with horizontally integrated, child-focused social services and longitudinally integrated health promotion strategies. Its mandate would be to develop the health of children in a community. The impetus for creating HDOs is a growing body of evidence in chronic disease epidemiology, developmental psychopathology, early intervention research, and life course cohort studies that point to childhood as the period of life during which adult health status is determined and the opportunities for health capital formation are highest. Thus, a new kind of health care organization or framework, like the HDO, is needed to integrate a full range of critical services for promoting children's development.

Hypothalamic and pituitary dysfunction in obese males.

Previous studies have indicated dysfunction of the hypothalamic-hypophyseal axis in obesity. We have studied 12 obese males to further characterize the extent of this dysfunction. The hypothalamic-hypophyseal-gonadal axis is normal as determined by the testicular response to human chorionic gonadotropin (hCG), the pituitary response to 200 micrograms gonadotropin-releasing hormone (GnRH), and the hypothalamic-pituitary-testicular response to clomiphene. Although L-dopa suppresses prolactin normally, the ability of thyrotropin releasing hormone (TRH) to stimulate the release of prolactin and thyroid stimulating hormone (TSH) is blunted. These latter responses are inversely related to the degree of obesity. The response to chlorpromazine, a hypothalamic stimulus for prolactin secretion, is also blunted, and to a greater extent than the prolactin response to TRH. These data indicate that exogenous obesity in males is associated with more extensive hypothalamic and pituitary dysfunction than previously realized. The abnormalities with regard to prolactin and TSH release become progressively worse when body weight exceeds 200 percent of ideal. In addition, when evaluating pituitary function with regard to gonadotropin release, obese males may have an abnormal response to 100 micrograms GnRH but respond normally to 200 micrograms.