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Biomedical subjects

W Hoffman

Publications and source records attributed to W Hoffman.

66 records · Page 4Linked to original sources
PubMed1972

Human prolactin and thyrotropin concentrations in the serums of normal and hypopituitary children before and after the administration of synthetic thyrotropin-releasing hormone.

Synthetic thyrotropin-releasing hormone (TRH) was administered to normal children and hypopituitary patients in a dose of 7 mug/kg i.v. over 30-60 sec. Serum thyrotropin (TSH) and prolactin (HPr) concentrations were measured by radioimmunoassay before and at 15-min intervals for 2 hr after TRH. In 20 normal children HPr rose from a mean baseline value of 7.0+/-1.2 (SEM) ng/ml to a mean peak value of 39.5+/-5 ng/ml. In 11 patients with growth hormone (GH) deficiency without TSH deficiency. HPr values rose from a mean baseline of 3.6+/-0.8 ng/ml to a mean peak value of 13.9+/-2.8, a significantly less peak response as compared with normal children (P < 0.005). The TSH responses to TRH, however, were statistically indistinguishable from those of normal children. In 10 patients with GH and TSH deficiency both the mean baseline HPr levels (25.0+/-5 ng/ml) and the mean peak HPr levels after TRH (68.5+/-10 ng/ml) were significantly higher (P < 0.005 and < 0.025) than those of normal children. Similar comparisons were also true for the peak TSH responses (P < 0.05). Two panhypopituitary patients released no TSH and only small amounts of HPr after TRH. After thyroid replacement therapy in eight of the patients with GH and TSH deficiency, the mean HPr baseline levels (7.6+/-1.0 ng/ml) and peak levels (23.3+/-4.6 ng/ml) after the same dose of TRH were significantly less than their pretreatment levels (P < 0.001 and < 0.01) and were within the range for normal children. Synthetic TRH stimulates the simultaneous release of TSH and HPr in normal children and most hypopituitary patients. When the concentrations of thyroxine (T4) and triiodothyronine (T3) are low, the levels of HPr before and after TRH are elevated. After thyroid replacement therapy, HPr levels decrease to normal. T4 and/or T3 may condition the production or effects of prolactin-inhibiting factor (PIF) activity. The TSH and HPr responses after TRH in hypopituitary patients will determine whether the primary defect resides in the pituitary or hypothalamus, but cannot delineate the hypothalamic defect as a deficiency of hypothalamic hormone production or neurohumoral transmission.

Adolescent↗
PubMedDate not supplied

Adjuvant polyarthritis. III. Evidence in support of viral etiology.

Intraperitoneal administration of a relatively small volume (0.2 ml) of plasma obtained from Sindbis virus--infected animals containing approximately 480 units of interferon/ml effectively suppressed the development of adjuvant arthritis. Similarly, administration of interferon (624 units/rat/day, ip) prepared in vitro by exposing rat embryo fibroblast culture to poly I:C in the presence of cycloheximide also suppressed the development of adjuvant arthritis without affecting the humoral or the cell-mediated immune response. The findings provide circumstantial evidence to the speculation that a virus or a virus-like organism plays a role in the pathogenesis of this disease.

Animals↗
PubMedDate not supplied

Organochlorine compounds: Risk of non-Hodgkin's lymphoma and breast cancer?

Organochlorines (i.e., synthetic chlorinated hydrocarbon compounds) are widespread, environmental contaminants that are present throughout the United States. Strong epidemiological evidence has linked occupational exposure to a high incidence of non-Hodgkin's lymphoma. Recently, it has been postulated that exposure to organochlorines increases the risk of developing breast cancer. Human data on this issue remain insufficient, but recent results are very consistent. Observations in human populations of the immunotoxic and hormone-mimicking properties of some organochlorines add biological plausibility to the epidemiologic findings. Limitations in our ability to measure organochlorine exposure still preclude a quantitative risk assessment, relative to these cancer endpoints. Public health action with respect to restriction of ongoing production and use of organochlorines, however, appears warranted for purposes of prevention.

Breast Neoplasms↗
PubMedDate not supplied

Cost containment in small hospitals: targeting strategies beyond this decade.

This study identifies the contributors to cost containment in small size, full-service hospitals (100-199 beds). A conceptual model has proposed and tested on data from 316 executives representing both for-profit and not-for-profit hospitals. The data suggest that the for-profit sector is more effective in managing its costs than its not-for-profit counterpart. However, the findings raise the issue of whether cost management leads to cost containment. The assumption of this study is that cost containment is a strategic concern, while cost management is operational.

Cost Control↗
PubMedDate not supplied

Followup study of possible HIV seropositivity among abusers of parenteral drugs in 1971-72.

Serum specimens obtained from a nationwide sample of parenteral drug abusers (PDAs) during the period 1971-72 had previously been screened for human immunodeficiency virus (HIV) antibodies. Some specimens were considered to be positive to both ELISA and Western blot (WB) analysis. These findings have been a topic of controversy, since HIV was not thought to have penetrated at-risk populations at such an early date. This study was a followup of those PDAs with apparent seropositivity to WB analysis. Of 10 persons followed, only one death (in 1985) was documented, and postmortem findings were inconsistent with HIV infection. Eight of the remaining PDAs were traced and found to be alive and well in 1989. Fresh specimens were obtained from the two persons with the strongest 1971-72 WB staining and were found to be both ELISA and WB negative on retesting. Their T-cell parameters were within normal limits. We concluded that the earlier WB results were most likely false positives and that definitive evidence of HIV infection in the U.S. addict population as early as 1971-72 is still lacking.

Blotting, Western↗