Effects of biosolubility on pulmonary uptake and disposition of gases and vapors of lipophilic chemicals.

Since statistical analysis proved the intercorrelation of tissue-gas partition coefficients of chemicals with similar chemical structures, bioavailability is controlled by one parameter dependent on the physicochemical properties of the chemicals and two constants distinguishing the tissues. Oil-gas partition coefficients are suggested to describe the biosolubility of volatile halogenated aliphatic chemicals. Tissue-gas partition coefficients derived from oil-gas partition coefficients were substituted in a pharmacokinetic model in order to study the effect of biosolubility on uptake, distribution, and elimination of inhaled chemicals.

Changes in the binding of oestradiol to uterine oestrogen receptors induced by some progesterone and 19-nor-testosterone derivatives.

The effects of two progesterone derivatives, namely medroxyprogesterone acetate (MPA) and chlormadinone, and two 19-nor-testosterone derivatives, namely norgestrel and norethisterone, on the binding of oestradiol to its cytoplasmic receptors in the rat uterus were compared. In experiments performed in vivo, the rats were given a single oral dose (15 mg/kg) of one of the four progestins and killed 1, 6, 24 and 48 h later. Norgestrel, norethisterone and MPA induced a prompt and remarkable decrease in oestradiol-receptor interaction 1 h after treatment.

Effects of bromocriptine and dopamine on the binding of estradiol to its uterine cytoplasmic receptors.

The in vivo and in vitro effects of bromocriptine on the binding of estradiol 17 beta to its specific uterine receptors were studied in both mature and immature rats. A single i.p.

The correlation between estrogen receptor status, axillary-node metastases and disease-free interval after surgery in primary breast cancer.

The prognostic value of estrogen receptor (ER) status in primary breast cancer was evaluated in 208 women subjected to Halsted radical mastectomy. The correlation between ER status, node involvement and disease-free interval after surgery was analyzed in detail. Forty-seven out of 127 ER-positive patients received hormonal adjuvant therapy, whereas the 81 ER-negative patients did not.

[Changes in hematologic parameters in 120 Somalian subjects].

We have studied in Somali subjects (120), compared with 120 Caucasus subjects the hemoglobin, the hematocrit, the number of red cells, the MCV, the MCH and MCHC. The results demonstrate that in Somali subjects have significant reduction of all parameters, and the reasons of those blood disorders in this tropical country must be associated with the scourges of poverty and malnutrition.

Effects of estrogens P-1496 and P-1560 on the binding of estradiol with rat uterine estrogen receptors.

The interference of two weak estrogens (P-1496 and P-1560) on the binding of estradiol with uterine estrogen receptors is comparatively studied. Both P-1496 and P-1560 decrease the estradiol binding capacity, but P-1560 is less effective than P-1496. Since P-1496 is a more potent estrogenic substance than P-1560, the results obtained confirm that the uterotrophic activity of estrogens is related to the binding capability to uterine estrogen receptors.

Changes in the concentration of uterine cytoplasmic oestrogen receptors induced by doxorubicin and methotrexate.

The effects of doxorubicin and methotrexate on the oestradiol-induced depletion, replenishment and subsequent increase beyond the normal value (overshoot) in the number of uterine cytoplasmic oestrogen receptors were investigated in intact rats. Injection of doxorubicin (0.5 mg/kg, i.

Determination of ethinyl estradiol in human urine by radiochemical GLC.

A radiochemical GLC analysis was developed for 3H-labeled ethinyl estradiol in human urine. The technique was applied to the unconjugated and aglycone fractions of urine collected from women who were dosed orally with: (a) single capsules containing 2.0 mg of 3H-quinestrol (900 muCi) and 2.

Bunolol metabolism by dogs: urinary excretion of 5-hydroxytetralone.

1. Anion exchange and t.l.

Assessment of the hazards of polybrominated biphenyls.

During their peak use period, PBBs represented under 1% of the total sales of fire retardant chemicals, and very probably would have escaped intensive study if they had not been mixed accidentally with animal feed preparations. Instead, international attention was drawn to PBBs by the state-supervised killing of over 35,000 cattle which had been contaminated with PBBs. Interestingly, low doses of PBBs exert a broad spectrum of toxicological, pharmacological, and biochemical effects despite low acute toxicity.

Interference of gestagens and androgens with rat uterine oestrogen receptors.

The inhibitory effect of some gestagens and calusterone on the binding of oestradiol-17beta to its specific uterine receptors has been investigated in intact rats. Progesterone, medrogestone, clogestone, medroxyprogesterone acetate and calusterone reduce the specific oestradiol-receptor interaction in vitro; this effect is dose-dependent and does not differ significantly from one drug to the other. A more relevant decrease in the amount of oestradiol-17beta bound to specific receptors has been observed with calusterone.

l-bunolol metabolites in human urine.

Nine radiolabeled compounds were identified in human urine after administering a single oral dose of 3H-l-bunolol (3 mg) to 5 male volunteers. These compounds represented 54.7% of the dose and 71.

l-Bunolol metabolism in rats: identification of urinary metabolites.

Urine collected for 24 hr from rats given a single oral dose of 3H-l-bunolol (10 mg/kg) was found to contain only 25.8% of the dose and more than 30 labeled compounds. Nine compounds were identified and quantified as follows: bunolol (0.

Metabolism of l-bunolol.

The metabolism of l-bunolol, a new beta-blocking drug, was studied in man after single oral 3-mg doses of 3H-labeled compound. Absorption from the gut was rapid and virtually complete. Peak levels of bunolol and of dihydrobunolol, an active metabolite, were observed at 1 hr.