Texas Medical Center

About: Texas Medical Center is a healthcare organization based out in Houston, Texas, United States. It is known for research contribution in the topics: Population & Cancer. The organization has 2845 authors who have published 2394 publications receiving 79426 citations.

Manifestation of Hyperplastic Alveolar Nodules and Mammary Tumors in “Viable Yellow” and Non-yellow Mice

Abstract: The time course of appearance of hyperplastic alveolar nodule(s) (HAN) and mammary tumor(s) (MT) was determined in untreated virgin "viable yellow" (Avy/A) and non-yellow (A/a) (C3H/HeNIcrWf X VY/Wf)F1 female mice. The first HAN was detected in a yellow female at age 16 weeks, the first period in which mice were killed. HAN were not found in the non-yellow mice until they were 19 weeks old. The incidence of HAN increased to 92% among yellow females and to 75% among non-yellow females by 36 weeks of age. MT were first observed at age 22 weeks in yellow mice and at 28 weeks in non-yellow mice. The incidence of MT at 36 weeks was 75% among yellow mice and 22% among non-yellow mice. Type B adenocarcinoma was the predominant class of MT found in the yellow mice. The time courses of appearance and incidence of HAN and MT in the non-yellow F1 mice were similar to those observed in inbred C3H female mice. MT first appeared in each population when the incidence of HAN bearers had reached 40--45% regardless of age, body weight, or number of HAN per HAN bearer. Apparently, the phenotypic effects of the Avy gene primarily stimulated the multiplication of nodule-transformed cells to form HAN and thus indirectly enhanced MT formation.

Physicochemical characterization of the androgen receptor from hyperplastic human prostate

Abstract: In this manuscript we have characterized the androgen receptor from human benign prostatic hypertrophied (BPH) tissue. BPH tissue was obtained fresh from surgery, ground, and frozen in liquid nitrogen. Tissue was homogenized in 10 mM Tes buffer (pH 7.4 at 25 degrees C) containing 0.25 M sucrose, 20 mM Na2MoO4, 12 mM monothioglycerol, and 1.5 mM EDTA. Cytosol was labeled with (3H)-R1881 (0.5-10 nM) +/- a 100-fold excess of R1881 and a 500-fold excess of triamcinolone acetonide to identify specific androgen receptor sites. An exchange assay was developed, whereby maximum binding was achieved by raising the temperature to 30 degrees C for 15 min. A high-affinity binding protein was detected (Kd = 1.3 +/- 0.8 nM) which had a binding capacity of 15 +/- 7 fmol/mg protein. Binding was specific for androgens with the following Ki (nM) values: R1881 (0.09), dihydrotestosterone (6), testosterone (50), progesterone (92), estradiol (100), epitestosterone (860), and cortisol (greater than 1,000). Under high ionic conditions the sedimentation coefficient of the receptor was 4.1 S. Higher S values were not observed in the presence of the following protein inhibitors: leupeptin (20 or 150 microM), iodoacetamide (10 mM), DFP (5 mM), PMSF (1 mM), bacitracin (0.1 mM), antipain (0.1 mM), aprotinin (1 TIU/ml). Gel filtration analysis revealed a Stokes radius of 6.5 nm. These data indicate a Mr of 120,000 and a f/fo of 2.01. The receptor eluted from a chromatofocusing column at a pH of 6.8. The receptor bound to phosphocellulose and DNA cellulose after being heat-treated for 15 min at 30 degrees C. These results suggest that BPH tissue contains an androgen receptor which is similar to receptors in other androgen-responsive tissues.