Modification of in vitro hematopoiesis induced by addition of GM-CSF in long term normal human bone marrow cultures

We have studied the effects of GM-CSF on cell growth in Dexter's type normal human long-term bone marrow cultures. Non adherent and adherent cells were weekly harvested and studied all over the time of culture up to 10 weeks: number, cytology, hematopoietic granulocyte-macrophage progenitors content (CFU-GM). Control consisted of cultures without growth factor. GM-CSF (100 ng/ml) induced a significant increase in the number of non adherent and adherent cells, mainly increasing the number of cells of the granulocytic lineage. GM-CSF also induced a transient increase in the number of CFU-GM in the non adherent fraction, but as from week 6 of culture, there were no more CFU-GM. At last GM-CSF inhibited completely or partially the adipocyte growth in the adherent stromal cell layers. In conclusion, at this concentration, GM-CSF might be responsible for the accelerated aging, maybe linked to the hematopoietic stem cells exhaustion and to the almost exclusive presence of monocyte-macrophage cell types in the culture supernatant.     

Evaluation of skin carcinogenicity of technical 2,2-bis-(p-glycidyloxyphenyl)-propane in CF1 mice

The carcinogenic potential of a technical-grade epoxy resin, Araldite® GY 250, of which the diglycidyl ether of bisphenol A (DGEBPA) is the main component, was investigated in CF1 mice. Groups of 50 male and 50 female mice were treated for 2 yr by repeated epidermal application of a 1 or 10% (v/v) solution in acetone. The controls, 50 mice of each sex, were treated with acetone alone. The treatment had no effect on survival and no excess incidence of skin tumours occurred. A positive control group of 50 male and 50 female CF1 mice was treated by epidermal application of 2% (v/v) β-propiolactone in acetone. In this group there was a high incidence of malignant skin tumours at the site of application and, consequently, increased mortality. Treatment with neither DGEBPA technical nor β-propiolactone induced systemic neoplasia.     

Adopting new models for continuity of care: the ward as mini-mental-health-center.

Several years ago the staff of a traditional psychiatric ward in a Veterans Administration hospital began trying to provide continual care for their former inpatients after they left the hospital. Nursing assistants conducted basic-skills groups and other groups in board-and-care homes; staff members made themselves available to former inpatients and theri families, roommates, or board-and-care sponsors through a 24-hour telephone service and home visits; and a day-care program and follow-up groups for the ward's outpatients were set up. Later the staff establiched additional day-care and follow-up programs in a downtown satellite unit. In a recent three month period, patients made a total of 4488 visits to the satellite and hospital programs. The preceding paper discusses some of the theoretical considerations on which this program and other alternatives to traditional care are based.     

Exposures to environmental toxicants and attention deficit hyperactivity disorder in U.S. children

OBJECTIVE: The purpose of this study was to examine the association of exposures to tobacco smoke and environmental lead with attention deficit hyperactivity disorder (ADHD). METHODS: Data were obtained from the National Health and Nutrition Examination Survey 1999-2002. Prenatal and postnatal tobacco exposure was based on parent report; lead exposure was measured using blood lead concentration. ADHD was defined as having current stimulant medication use and parent report of ADHD diagnosed by a doctor or health professional. RESULTS: Of 4,704 children 4-15 years of age, 4.2% were reported to have ADHD and stimulant medication use, equivalent to 1.8 million children in the United States. In multivariable analysis, prenatal tobacco exposure [odds ratio (OR) = 2.5; 95% confidence interval (CI), 1.2-5.2] and higher blood lead concentration (first vs. fifth quintile, OR = 4.1; 95% CI, 1.2-14.0) were significantly associated with ADHD. Postnatal tobacco smoke exposure was not associated with ADHD (OR = 0.6; 95% CI, 0.3-1.3; p = 0.22). If causally linked, these data suggest that prenatal tobacco exposure accounts for 270,000 excess cases of ADHD, and lead exposure accounts for 290,000 excess cases of ADHD in U.S. children. CONCLUSIONS: We conclude that exposure to prenatal tobacco and environmental lead are risk factors for ADHD in U.S. children.     

Plasma free cyanide and blood total cyanide: a rapid completely automated microdistillation assay

Techniques are presented which provide direct measurement of both free cyanide (CN-) in plasma and total CN- in whole blood. Loss of total CN- from blood is prevented by conversion to cyanmethemoglobin. Both free and total CN- are assayed by a completely automated method providing readout 17 minutes after sampling. No prior isolation technique is required and sensitivity is adjustable to cover a broad range of CN- concentrations from 1 to 4000 uM. Precision of blood CN- values from 2 to 2500 uM is within +/- 2.3%. No interference results from thiocyanate or thiosulfate at a concentration of approximately 1 mM.     

Drug safety in the treatment of Crohn's disease

The management of Crohn's disease usually consists of a succession of short-term acute phase treatments followed by long-term maintenance therapy. The disease affects young patients and for this reason the long-term safety of the drugs needs to be especially taken into consideration. The safety, dose, duration for optimal efficacy and the most frequent adverse events will be described in this article.