Effect of microtubule reactive drugs on steroid- and centrifugation-induced germinal vesicle migration during goldfish oocyte meiosis.

During the process of progestogen-induced meiotic maturation in the goldfish oocyte, the oocyte nucleus (germinal vesicle, GV) migrates to the sperm entry site or micropyle at the animal pole. Following GV migration (GVM) to the micropyle, the nuclear membrane undergoes dissolution (GVD) and the cell enters metaphase I in preparation to generate the first polar body. Microtubule destabilizing drugs including colcemid, nocodazole and vinblastine were found to elicit GVM, mimicking the process which occurs just prior to the prophase I-metaphase I transition during steroid induced oocyte meiotic maturation.

Estradiol-17 beta Silastic implants suppress oocyte development in the brook trout, Salvelinus fontinalis.

A technique for long-term implantation (i.e., 6 months) of steroid-containing Silastic capsules in brook trout was developed along with a method for longitudinal study of ovarian dynamics in individual females.

Characterization of gonadotropin-releasing hormone (GnRH) binding to pituitary receptors in goldfish (Carassius auratus).

Goldfish pituitary gonadotropin-releasing hormone (GnRH) receptors were characterized by using a superagonist analog of teleost GnRH (tGnRH-A; [D-Arg6, Trp7, Leu8, Pro9-NHEt]-GnRH). Equilibrium binding of 125I-tGnRH-A to a goldfish pituitary membrane preparation was achieved after a 30-min incubation at 4 degrees C; binding was significantly reduced after increasing incubation temperature to 22 degrees C. Binding of the radioligand was a function of tissue concentration, with a linear correlation over the range of 0.

A study of goldfish oocyte meiosisin vitro: effects of 2,4-dinitrophenol and adenosine-5-triphosphate.

Germinal vesicle migration (GVM) and/or dissolution (GVD) were measured in goldfish oocytes, treated with 17α, 20β dihydroxyprogesterone (DHP) and other compounds considered to effect the cytoskeleton and oxidative phosphorylation,in vitro. Administration of DHP reinitiated meiotic maturation, increasing GVM and GVD in goldfish oocytes. Addition of 2,4-dinitrophenol (DNP) to the incubation medium significantly inhibited DHP-induced GVM and GVD.

Effects of cytochalasin B on steroid-induced oocyte meiosis and centrifugally induced nuclear movement in the goldfish Carassius auratus.

In goldfish, 17 alpha, 20 beta-dihydroxyprogesterone (DHP) induced oocyte nucleus or germinal vesicle migration (GVM) and dissolution (GVD) in a dose-related fashion. Administration of cytochalasin B (CB) in the presence of DHP inhibited the steroid-induced GVM and GVD after 24 and 48 h of incubation. The presence of CB alone, at concentrations below 25 micrograms/mL, had no effect on GVM or GVD.

The effect of low-dose cyclophosphamide and immunologic exposure upon growth of established Dunning R-3327-G subline rat prostate adenocarcinomas.

Utilizing the Dunning rat prostate adenocarcinoma, a low dose of cyclophosphamide (CY), 30 mg/kg, administered either alone or following diethylstilbestrol (DES) therapy, was as effective as higher levels of CY (100 mg/kg) in ability to initiate tumor regression. A lower dose (10 mg/kg) of CY was initially ineffective. Animals which had been injected with tumor an additional 10 days prior to initiation of CY treatment were apparently more responsive to this mode of chemotherapy.

Pelvic lymph node dissection in prostate cancer.

The results of pelvic lymph node dissections in 105 prostate cancer patients were analyzed to compare the clinical with the pathologic stages. Twenty-four per cent of patients clinically believed to be node-negative had positive nodal involvement with cancer.

A study of androgen-stimulated L-leucine transport by the intestine of rainbow trout (Salmo gairdneri Richardson) in vitro.

The intestinal transport of L-leucine and fluid was studied in response to in vitro administration of 17 alpha-methyltestosterone (MT; 50 micrograms/ml) and 11-ketotestosterone (KT; 10 micrograms/ml), using strips of rainbow trout intestine incubated for 60 min in vitro. Both MT and KT increased the intestinal absorption of the amino acid without significantly affecting fluid transport. Addition of ouabain, 2,4-dinitrophenol (DNP) and sodium fluoride (NaF) reduced the intestinal transport of leucine.

Effects of steroids and sex reversal on intestinal absorption of L-[14C]leucine in vivo, in rainbow trout, Salmo gairdneri.

The effects of steroids (17 alpha-methyltestosterone (MT), 17 beta-oestradiol (E2)), and of sex reversal (XX male) on intestinal absorption and accumulation of L-[14C]leucine (5 mM), were investigated in unanaesthetized rainbow trout (Salmo gairdneri), using an in vivo gut perfusion technique. Each steroid was luminally perfused through the gut at a concentration of 50 micrograms/ml perfusate, during five separate perfusions carried out on the same fish at 30-min intervals (perfusion periods 1 to 5), for a total of 120 min at 14 degrees. Experiments were also conducted on masculinized, genetically female trout (XX male) with steroid-free perfusate.

Case report of an ovarian hydatid cyst.

Hydatid cyst is a parasitic disease caused by Taenia echinococcus. The first and most important site for this parasite is the liver. Secondary involvement of the pelvic organs is seen.