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Biomedical subjects

J Geller

Publications and source records attributed to J Geller.

At least 127 records · Page 7Linked to original sources

Dihydrotestosterone concentration in prostate cancer tissue as a predictor of tumor differentiation and hormonal dependency.

Tissue dihydrotestosterone and 5alpha-reductase (delta4-3-ketosteroid-5alpha-oxidoreductase) levels have been measured in prostates of patients with cancer and benign prostatic hypertrophy; significant decreases in average values for both of these biochemical parameters were noted in prostate cancer compared to benign prostatic hypertrophy, although individual values overlapped in both groups. Prostate cancer tissue dihydrotestosterone levels appeared to correlate better than did either histological tumor grading or 5alpha-reductase with the ultimate clinical response to antiandrogen therapy. These results suggest that assay of tissue dihydrotestosterone levels in prostate cancer should be further explored as a possible marker for tumor differentiation.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

Utilization review of the late adolescent patient in a mental health center: steps toward the development of criteria for the adequacy of assessment and treatment.

This study is concerned with an attempt to determine whether meaningful utilization review criteria could be productively generated by viewing a patient population from a developmental perspecitve. During a 2-year period, a multidisciplinary panel at Yale University sought to identify the sociodemographic, clinical, and administrative issues posed by late adolescents seeking treatment at the Connecticut Mental Health Center, New Haven. We sought to address the following questions: a) From what segment of the population were we drawing our adolescent patients? b) Who referred them for help? c) What kinds of problems led to referral? d) What were the diagnostic characteristics of the adolescent's evaluation? e) Under what conditions do adolescents terminate treatment? The charts of over 1222 adolescent patients were studied to help us answer these questions. Our investigation revealed that the adolescent patients seen at the Mental Health Center were sociodemographically and diagnostically heterogeneous. An increasingly large number of adolescents are referring themselves for evaluation and treatment, rather than being sent by schools, physicians, or social welfare agencies. The majority of patients seeking help come from blue collar or working class backgrounds mainly because of intrapsychic complaints of anxiety and depression. Upwardly mobile, they constitute a group who have completed their high school education, often live away from home, and are struggling with problems of defining an identity different from that of their family. Review of their charts indicated that significant sholastic, medical, and developmental information was frequently lacking or vaguely recorded. Our chart review also indicated that many clinicians did not ask their patients about symptoms relating to body functioning such as difficulties with sleeping, eating, or psychosomatic complaints. The study also discovered that it was difficult in the great majority of the charts reviewed to specify the adolescent's own perception of the difficulties which led them to seek help. Suggestions are then outlined for developing review criteria dealing with the emancipated adolescent, parental involvement in the treatment of the adolescent, treatment plans, and the termination of treatment. The comparative advantages of combining utilization review criteria from both a traditional "disease model" and a "developmental model" are discussed. The panel concluded that input from both perspectives is necessary in understanding the impact of a mental health delivery system upon adolescent patients, their family, and the community.

Adolescent↗

A method for tissue extraction and determination of prostate concentrations of endogenous androgens by radioimmunoassay.

A method for simultaneously determining concentrations of major androgens in prostate has been developed. Extraction techniques used to isolate the androgens from minced tissue include homogenization with high-speed blades in Delsal's solvent mixture, adsorption to silica gel, followed by column and one thin-layer chromatography (TLC). Radioimmunoassays (RIA) of small aliquots of TLC eluates are used to quantitate picogram amounts of 5alpha-dihydrotestosterone (DHT) and 5alpha-androstanediols (Diol) and to estimate testosterone (T) and androstenedione (Ad). Contamination of blanks was reduced to RIA sensitivity limits primarily by treatment of glassware in a self-cleaning oven. The specificity of the method for each androgen was established by TLC separations of known prostate metabolites, antisera specificities, and parallelism of sample aliquots to androgen RIA standards. The overall precision, in terms of coefficients of variation, was 21% for DHT and 24% for Diol. T and Ad could not be measured with acceptable precision because their very low concentrations in prostate (less than or equal 0.5 ng/g tissue) were less than RIA sensitivity limits. Accuracy studies indicated recoveries ranging from 96% for Diol to 121% for DHT. In human benign hypertrophic prostate tissue, DHT averaged 153 ng/g soluble protein (5.8 ng/g tissue) which was 17 times higher than values obtained in human spleen and kidney; Diol in prostate showed no consistent differences from values noted in kidney or spleen.

Androgens↗

Comparison of androgen metabolites in benign prostatic hypertrophy (BPH) and normal prostate.

5 alpha-Dihydrotestosterone (DHT) and androstanediols (diols) have been measured in human prostate tissue. DHT levels in surgical specimens of prostate from 8 patients with BPH averaged 5.6 +/- 0.93 S.E. ng/g and were significantly greater than (P less than 0.01) values of 2.1 +/- 0.32 S.E. ng/g in 6 normal prostates obtained post-mortem from males less than 50 yrs old. Androstanediols averaged 2.3 +/- 0.35 S.E. ng/g in the BPH specimens compared to values of 10.2 +/- 2.4 S.E. ng/g in the normal prostates (P less than 0.01). This significantly higher (P less than 0.001) ratio of diols/DHT in the normal (5.1 +/- 0.93 S.E.) compared to the BPH prostate (0.45 +/- 0.08 S.E.) suggests that a decrease in 3-hydroxysteroid oxido-reductase, which converts DHT to diol, may be an important clue to the pathogenesis of BPH.

Androstane-3,17-diol↗

Effect of megestrol acetate (Megace) on steroid metabolism and steroid-protein binding in the human prostate.

Megestrol acetate (Megace), an antiandrogen, was administered in a dosage of 80 mg daily to 6 patients with benign prostatic hypertrophy (BPH) for 4 to 25 days prior to transurethral resection of the prostate (TURP). Surgical tissue from drug-treated patients was compared to untreated controls in regard to: 1) the enzymatic reduction of testosterone (T) and dihydrotestosterone (DHT); 2) DHT binding to a cytosol receptor protein; 3) tissue levels of endogenous dihydrotestosterone and androstanediols (diols). When minced prostate was incubated with 3H-T and 14C-androstenedione for 1 h at 37 C, prostate 5alpha-reductase activity, measured as reduced products formed from substrate, decreased to 31% and 39%, respectively, of the control values. Prostate 3-oxido-reductase enzyme activity, measured as diols formed from 3H-DHT, was decreased to neglible values in Megace-treated patients compared to an 8.7% conversion to diols in controls. No 3H-DHT binding to a cytosol receptor protein could be demonstrated in 4 out of 5 prostates from Megace-treated patients, whereas the presence of such a receptor was noted in 14 out of 17 untreated controls. Endogenous DHT levels in Megace-treated patients averaged 1.1 ng/g (SE = 0.26), significantly less than the average of 3.9 ng/g (SE = 0.49) found in controls (P less than 0.001). No significant difference was noted in endogenous diols. In addition to these effects on tissue, Megace significantly decreased plasma levels of T, LH, and FSH at the end of the 4- to 25-day period; plasma prolactin levels did not change. Continued studies of Megace for the possible treatment of benign prostatic hypertrophy may be warranted since the drug appears to block several important biochemical steps which mediate the effects of androgen on the human prostate.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

Evidence for a specific dihydrotestosterone-binding cytosol receptor in the human prostate.

A technique for the demonstration of a human steroid and organ-specific prostate cytosol receptor is described. Tissue from 17 patients with benign prostatic hypertrophy was incubated in Eagle's medium with 3H-testosterone (T) .06 nM following pre-incubation with an anti-androgen. The minces were homogenized and the cytosol fraction obtained. The cytosol was then fractionated on a duo-gel column of G-50 Sephadex over Bio-gel A 1.5m and fractions counted for 3H, assayed for protein and plotted graphically. Three main peaks were seen. Only the second peak (approximately 150,000 mol wt), which contained predominantly dihydrotestosterone (DHT), was significantly and reproducibly inhibited by 2.1 muM cyproterone acetate (Cyp A) pre-incubation. This inhibiton was considered a specific indicator for receptor since Cyp A at muM had little effect (less than 10%) on 3H-DHT binding to plasma. Similar results were noted for other anti-androgens tested, but cortisol and etiocholanolone had no effects on 3H-5alpha DHT binding to prostate cytosol. Steroid-protein peaks for fractionated human thyroid, muscle, and spleen cytosol were not inhibited by Cyp A. Fractionated kidney cytosol contained a 3H-T-binding protein peak which was significantly decreased by Cyp A. Pronase incubation and heating at 50 C for 30 min both resulted in either a significant decrease or complete loss of receptor. Gel filtration analysis of 3H-cytosol derived from human prostate minces pre-incubated with and without Cyp A, provides a relatively rapid technique for the demonstration of cytosol receptor in approximately 80% of prostates from patients with benign prostatic hypertrophy.

Aged↗