Search results for "Diethylstilbestrol"
showing 10 items of 18 documents
Phosphorylated intermediate of a transport ATPase and activity of protein kinase in membranes from corn roots
1983
A maize-root microsomal fraction was enriched in ATPase by treatment with Triton X-100. This activity, which reached 1.2-2.0/mumol Pi x min-1 x mg protein-1, was specific for ATP, very slightly stimulated by K+, inhibited by orthovanadate and diethylstilbestrol, resistant to oligomycin and azide, and had a Km of 1.2 mM MgATP. Incubation of the microsomal fraction with [gamma 32-P]ATP followed by electrophoresis in acid conditions revealed the presence of several phosphoproteins. The phosphorylation of a 110000-Mr polypeptide reached the steady-state level in less than 5 s and rapidly turned over the phosphate group. The phosphorylation level was an hyperbolic function of the [ATP] with a Km…
Soluble and nuclear oestrogen receptor status of advanced endometrial cancer in relation to subsequent clinical prognosis
1987
Both soluble and nuclear oestrogen receptors have been measured in at least two separate sections from 72 endometrial cancers and 12 normal endometria. Concentration of oestrogen receptor is shown to be, in our hands, more meaningful when expressed per unit DNA than per unit protein, whether for soluble or nuclear receptor. Endometrial cancer cells from the central part of the tumour are shown to be receptor negative more frequently than those from peripheral tumour. Thus, in large cancers, biopsies from different areas are required before a tumour can be correctly designated as receptor positive, heterogeneous or receptor negative. The intratumoral variation of receptor status may relate t…
The effects of histamine on the isolated mouse uterus
2000
1. A study is made of the contractile and relaxant effects, and mechanism of action, of histamine on isolated uterus from mice treated with diethylstilboestrol, employing acetylcholine and adrenaline as contractile and relaxant standard agents. 2. Concentration-response curves for histamine agonists were obtained in the absence and presence of selective histaminergic blocking drugs (clemizole, ranitidine and thioperamide) and indomethacin. A number of experiments were carried out in uterus from reserpinised mice. Concentration-response curves for acetylcholine and adrenaline were also obtained in the absence and presence of their selective antagonist (atropine and propranolol). 3. In isolat…
Study on the histamine-like activity of guanfacine
1990
Abstract The effects of guanfacine have been studied on guinea-pig isolated atria and diethylstilboestrol-treated rat isolated uterus to determine whether it possesses histamine-like activity. Guanfacine produced a concentration-dependent negative chronotropic effect which was not modified by ranitidine (0.1 μM). In rat isolated uterus contracted by KCl, clonidine (5–5000 μM) produced concentration-dependent relaxation which was blocked by ranitidine (0.1 μM), but guanfacine only produced relaxation at high concentrations (100–1000 μM), and this was not affected by ranitidine (0.1 μM). It is concluded that guanfacine, unlike clonidine, does not produce effects due to activation of H2-recept…
Estrogen-Induced Mutations and Its Role in the Development of Tumorigenesis
2006
Using RAPD-PCR fingerprinting, the detection of mutations induced by estrogen (E) exposure was studied in nonmalignant- and malignant cells. Cells exposed to 17α-and 17β-estradiol, diethylstilbestrol, bisphenol A, and α-zearalanol induced mutations in different regions of the genome. They consisted of insertion/deletion as a result of point or length mutations and quantitative changes as a result of hypoploidy or polyploidy. We also detected several mutated loci in tumor-free tissues, adjacent to tumors, and DES-induced tumors. The data suggest that these mutations occurred in early stages of stilbene E-induced renal carcinogenesis, and that they may be induced as a result of stilbene E tre…
Activity and immunohistochemistry of DT-diaphorase in hamster and human kidney tumours.
1994
We have studied the biochemical and immunohistochemical changes of DT-diaphorase in diethylstilbestrol (DES)-induced hamster kidney tumours and human biopsies from normal kidneys and renal clear cell carcinoma. The activities of primary and secondary antioxidants in these hamster and human tissues are also reported. DT-diaphorase is decreased in the different subcellular fractions of hamster and human tissues. In hamster kidney the activities of the one-electron quinone reductases show a nearly two-fold increase. Immunohistochemical findings confirm the decrease in DT-diaphorase in hamster and human tissues. This image is of special interest in the case of nephroblastoma (Wilms' tumour), si…
The levels of quinone reductases, superoxide dismutase and glutathione-related enzymatic activities in diethylstilbestrol-induced carcinogenesis in t…
1990
The level of quinone oxidoreductases (microsomal and cytosolic DT-diaphorase, NADPH-cytochrome P450 reductase and NADH-cytochrome b5 reductase), superoxide dismutase and glutathione-related enzymatic activities in diethylstilbestrol (DES)-induced carcinogenesis in kidney from Syrian golden hamsters are presented. Animals that exhibited two different stages of DES-induced carcinogenesis in kidney--pre- and neoplastic lesions and tumorous lesions (after 6 and 8 months of continuous exposure to DES respectively)--were studied in comparison to kidneys from control animals. A dramatic decrease in microsomal and cytosolic DT-diaphorase activities (13.6 and 37.8% of controls), as well as in glutat…
Inhibition of Platelet Aggregation Caused by Estrogen Treatment in Patients with Carcinoma of the Prostate
1975
Platelet aggregation is increased in patients with carcinoma of the prostate treated with estrogens. Hence, these patients have a high incidence of cardiovascular and thromboembolic diseases. Platelet aggregation has been tested with the platelet aggregation test. It was inhibited by administration of 500 mg. acetylsalicylic acid twice daily. An aggregation inhibiting effect has been found in all 38 patients. To reduce the excess hazards of cardiovascular complications of estrogens in treating carcinoma of the prostate acetylsalicylic acid is recommended as an adjunct therapy.Estrogen therapy for prostatic carcinoma may lead to the development of cardiovascular complications, such as thromb…
Followup of irradiated prostatic carcinoma by aspiration biopsy.
1977
AbstractOf 66 patients with irradiated prostatic carcinoma 53 were controlled regularly by repeat aspiration biopsy every 6 months. Local sterilization was achieved in 43 per cent but the results of combined radiotherapy (endocrine therapy plus irradiation) were only 8 per cent more favorable than those in patients treated by radiotherapy alone. Thus, endocrine therapy is not warranted before the radiation effect is evaluated. Post-radiation treatment should be determined by the clinical and bioptic findings.
Alteration of poly (ADP-Rib) synthesis during progesterone- caused gene expression in oviducts of quails.
1976
Summary The biological model of the selective induction of RNA synthesis in oviducts of estrogen stimulated immature quails by progesterone has been used to clarify whether poly (ADP-Rib) is involved in DNA transcription. The chromatin-bound as well as the soluble poly (ADP-Rib) polymerase has been isolated from oviducts and the optimal reaction conditions have been determined. The activities, as measured by the incorporation rates of NAD + into poly (ADP-Rib), of both, chromatin-bound « endogenouspolymerase (in the absence of « exogenousDNA and histones) and soluble enzyme (native DNA - lysine-rich histone ratio: 4.3) from progesterone treated quail oviducts, have been determined to be onl…