A 28-day feeding study with methyl isoeugenol in rats.

Methyl isoeugenol was administered in rodent diet for a minimum of 28 consecutive days to groups of 16 male and 16 female rats (Sprague-Dawley strain) at levels of approximately 30, 100 and 300 mg/kg body weight/day. A further group of 16 male and 16 female rats was given the rodent diet as a control. The administration of methyl isoeugenol in the diet did not adversely affect the growth or general health of the animals or their food intakes. Although high dose animals of both sexes had increased lymphocyte and total white blood cell counts, these are not considered, in isolation, to be an adverse effect of treatment. None of the minor variations observed in the serum chemical analyses or urine analyses is considered to be indicative of a treatment-related toxic effect. An increase in liver weight, adjusted for body weight, was seen in male and female rats receiving 300 mg methyl isoeugenol/kg body weight. Few histopathological abnormalities were observed. Although the incidence of kidney and Harderian gland lesions was higher for high dose animals compared with the controls, the lesions are of a type that occurs spontaneously and are thus not considered to be attributable to treatment with methyl isoeugenol. While the increased liver weight and white blood cell counts of rats given 300 mg methyl isoeugenol/kg body weight may represent effects of treatment, it is not considered that there is any reason to regard these as adverse effects.     

Absence of percutaneous absorption of aflatoxin

Aflatoxin, dissolved in dimethylsulfoxide or acetone, was applied to the shaved skin between the shoulder blades of rats. Half of the rats were anesthetized. No aflatoxin was found in the internal organs of anesthetized rats at 20 or 130 min after skin application. Aflatoxin was found on the paws and in the stomach, liver, and kidney of conscious rats indicating that aflatoxin is ingested after being removed from the skin by the paws during grooming. Larger quantities of aflatoxin were ingested when it was applied dissolved in dimethylsulfoxide than in acetone presumably because dimethylsulfoxide is less volatile and, therefore, easier to remove during grooming. There was no evidence of percutaneous absorption. These findings explain how aflatoxin which is applied to rat skin produces hepatic lesions.     

Staphylococcal epidermidis infection of a hemodialysis button-graft complex controlled by vancomycin for 11 months

A 54 year old woman had a Bentley DiaTAP button implanted in her thigh for hemodialysis access. She had been started on continuous ambulatory peritoneal dialysis (CAPD) because of intractable vascular access problems. Unfortunately, CAPD had to be discontinued because of fungal peritonitis. Transplantation had not been possible because of circulating cytotoxic antibodies. The prosthetic complex soon became infected with Staphylococcus epidermidis and blood cultures were intermittently positive for 11 months. However, with continuing vancomycin therapy she remained in her usual state of health, without side effects from vancomycin, until venous thrombosis resolved and it became possible to remove the infected prosthetic complex and implant a button in an arm. As a last resort, it may be possible to maintain a patient on dialysis in reasonable health with a DiaTAP button graft complex infected with Staphylococcus epidermidis and intermittent positive blood cultures using long term vancomycin therapy. Such management probably would not be appropriate for any other organism.     

Reduced risk of hepatitis B and hepatitis C among injection drug users in the Tacoma syringe exchange program.

OBJECTIVES. This case-control study examined the association between syringe exchange use and hepatitis B and C in injection drug users. METHODS. Case patients included 28 injection drug users with acute hepatitis B and 20 with acute hepatitis C reported to the health department in a sentinel hepatitis surveillance county; control subjects were injection drug users with no markers of exposure to hepatitis B or C (n = 38 and 26, respectively) attending health department services during the same period. Data were abstracted from clinic records. RESULTS. Seventy-five percent of case patients with hepatitis B and 26% of control subjects had never used the exchange; similar proportions were found for the hepatitis C case and control groups. After adjustment for demographic characteristics and duration of injecting drugs, nonuse of the exchange was associated with a sixfold greater risk of hepatitis B (odds ratio [OR] = 5.5; 95% confidence interval [CI] = 1.5, 20.4) and a sevenfold greater risk of hepatitis C (OR = 7.3; 95% CI = 1.6, 32.8). CONCLUSIONS. The results suggest that use of the exchange led to a significant reduction in hepatitis B and hepatitis C in the county and may have also prevented a substantial proportion of human immunodeficiency virus infections in injection drug users.     

Lymphoid leukosis in chickens chemically bursectomized and subsequently inoculated with bursa cells.

Lymphoid leukosis (LL), a neoplasm of the bursa-dependent lymphoid cells of the chicken, was induced by Rous-associated virus-1 in susceptible chickens. Cyclophosphamide (CY), which destroyed the lymphoid elements of the bursa of Fabricius and abrogated humoral immunity, prevented LL. Concomitantly, osteopetorosis and other neoplasms increased. Transfer of bursa cells from chickens into CY-treated hatchmates restored immune competence. Birds whose B-cell functions were reconstituted died of LL and were less likely to die of osteopetrosis and other neoplasms than were CY-treated chicks. These results suggested that the bursa cell transferred into the CY-treated chicks were the target cells for lymphoid leukosis transformation.     

抗肿瘤药物产销现状及发展

本文论述了当前国内外抗肿瘤(癌)药物的产销现状。从新药研究和抗肿瘤药物发展趋势要求出发,提出了我国研究开发抗癌药的六个方面建议,希望能对我国抗癌药物研究开发工作有所帮助。