Synthetic estrogens and tamoxifen as promoters of hepatocarcinogenesis.

Previously, we demonstrated that the synthetic estrogens mestranol and ethinyl estradiol (EE) were strong promoters of hepatocarcinogenesis initiated in intact female rats by prior treatment with diethylnitrosamine (J. D. Yager, H.

Schistosoma mansoni and S. japonicum: comparison of levels of ultraviolet irradiation for vaccination of mice with cercariae.

When cercariae of Schistosoma mansoni and of S. japonicum were irradiated with various levels of u.v.

Regulation of rat hepatocyte epidermal growth factor receptor by the liver tumor promoter ethinyl estradiol.

We have previously demonstrated that the liver tumor promoter ethinyl estradiol (EE) greatly enhanced the DNA synthetic response of rat hepatocytes in primary culture to epidermal growth factor (EGF). This effect was associated with a 2-fold increase in surface EGF receptor number. In this report, we demonstrate that the increase in cell surface [125I]EGF binding caused by EE is time dependent, beginning at 8 h and reaching a plateau at 18 h.

Schistosoma japonicum: an ultraviolet-attenuated cercarial vaccine applicable in the field for water buffaloes.

Water buffaloes were vaccinated three times with 10,000 Schistosoma japonicum cercariae irradiated with ultraviolet (uv) light at a dose of 400 microW x min/cm2. The irradiation was performed with cheap, simple, and portable equipment in a rural area of Hubei Province (People's Republic of China). A challenge infection of 1000 untreated cercariae was given to six vaccinated and six naive control buffaloes, while two vaccinated animals were not challenged.

Comparative cross-over pharmacokinetic study on two types of postcoital contraceptive tablets containing levonorgestrel.

A pharmaceutical and pharmacokinetic study was carried out on levonorgestrel tablets from two different sources (Hungarian- and Chinese-made). Both preparations contained 0.75 mg levonorgestrel and had been shown to have similar contraceptive efficacy and side effects when used for postcoital contraception.

Metabolism of the liver tumor promoter ethinyl estradiol by primary cultures of rat hepatocytes.

Previously, we reported that relatively high micromolar concentrations of the liver tumor promoter 17 alpha-ethinyl estradiol (EE2) stimulated DNA synthesis and enhanced the DNA synthetic response to epidermal growth factor (EGF) in primary cultures of female rat hepatocytes [J.D. Yager, B.

Pharmacokinetic study of orally administered RU 486 in non-pregnant women.

A method based on HPLC was devised for the estimation of RU 486 in blood and utilised to study the pharmacokinetics of a single dose of 50 mg RU 486 administered orally to 12 women on day 7 of the cycle. The dose was rapidly absorbed with peak plasma concentration between 1 and 2 hours. Distribution was also rapid (mean t1/2 alpha: 1.

Termination of early human pregnancy with RU 486 (mifepristone) and the prostaglandin analogue sulprostone: a multi-centre, randomized comparison between two treatment regimens.

A multi-centre, randomized trial was conducted to compare the efficacy and side-effects of two combination regimens of the antiprogestin RU 486 and the intramuscular PGE2 analogue sulprostone for termination of early pregnancy (amenorrhoea up to 49 days). Women in the 3-day group (n = 125) received 25 mg RU 486 twice daily for 3 days plus a single injection of 0.25 mg sulprostone in the morning of the third day of antiprogestin treatment.

Effects of the liver tumor promoter ethinyl estradiol on epidermal growth factor-induced DNA synthesis and epidermal growth factor receptor levels in cultured rat hepatocytes.

The objective of this study was to determine whether DNA synthesis induced in the livers of female rats treated with ethinyl estradiol (EE) was due to direct effects of this synthetic estrogen on hepatocytes. Hepatocytes, obtained by collagenase perfusion from female Lewis rats, were cultured in serum-free medium containing low or no phenol red and supplemented with insulin, transferrin, and selenium. When present at 10-15 microM for the initial 30 h of culture, EE caused a subsequent 2-2.

Enhancement in rats by the liver tumor promoter ethinyl estradiol of a serum factor(s) which is stimulatory for hepatocyte DNA synthesis.

Fractionation of female rat serum or plasma on Sephadex G-200 revealed the presence of an activity stimulatory for hepatocyte DNA synthesis. Treatment of female rats with the liver tumor promoter ethinyl estradiol (EE) at 2.5 micrograms/day caused a 1.

The effect of levonorgestrel administered in large doses at different stages of the cycle on ovarian function and endometrial morphology.

In a pharmacokinetic study, levonorgestrel (L-NOG) 0.75 mg was administered orally to 10 swedish women in the early follicular phase of the menstrual cycle. L-NOG levels were measured after L-NOG administration.

Schistosoma mansoni: effect of gossypol on infections in mice.

Gossypol, a toxic drug present in cotton seed oil, was subcutaneously injected into mice infected with Schistosoma mansoni. Injections were given daily over three 15 day-periods covering, respectively, schistosomula migration through skin and lungs, parasite establishment in the mesenteric veins and the schistosome sexual maturation phase. Worms were recovered by mesenteric perfusion and eggs were counted in livers and intestines 52 days after infection.

Pharmacokinetic study of levonorgestrel used as a postcoital agent.

The pharmacokinetics and pharmacodynamics of levonorgestrel (LNG) were studied in six women given 0.75 mg LNG orally for seven days during the periovulatory phase of the menstrual cycle. Steady-state concentrations of LNG were reached within three days and serum LNG concentrations at various times on day 7 were generally lower than on day 1, presumably due to a reduced serum level of SHBG.

Postcoital contraception with levonorgestrel during the peri-ovulatory phase of the menstrual cycle. Task Force on Post-ovulatory Methods for Fertility Regulation.

The contraceptive efficacy and side effects of postcoital levonorgestrel used repeatedly during the peri-ovulatory period of one cycle was examined in 259 women. All subjects were of proven fertility in their present union and had ovulatory cycles as assessed from pre-treatment BBT charts. The mean number of coital acts during the treatment cycle was 7.

Sera of Schistosoma japonicum-infected patients cross-react with diagnostic 31/32 kD proteins of S. mansoni.

Schistosoma mansoni adult worm antigens were tested for cross-reactions with sera obtained from patients infected with S. japonicum. The sera consistently recognized a doublet of bands, in immunoblots, which had molecular weights of approximately 31 and 32 kilodaltons (kD).

Pharmacokinetics of norethisterone in humans.

The pharmacokinetics of a dose of 1mg norethisterone administered with 50 micrograms ethynyloestradiol was studied in 83 subjects. The dose was rapidly absorbed and there were wide variations in the serum NET concentrations at any particular time after dosing; the concentrations at 24 h varied from 100 to 1700 pg/ml. There was a significant negative correlation between the serum NET concentration and the time after dosing in all women.