Search PubMed⌕ Search

Biomedical subjects

S H Weinstein

Publications and source records attributed to S H Weinstein.

At least 37 records · Page 2Linked to original sources

Preliminary observations on the results of combined 125iodine seed implantation and external irradiation for carcinoma of the prostate.

Fifty-seven patients with localized carcinoma of the prostate were treated with pelvic lymphadenectomy and a reduced 125iodine implant dosage, supplemented by a moderate dose of external beam radiotherapy to the whole pelvis delivered 4 to 6 weeks later. The incidence of pelvic nodal metastases was 28 per cent and the operative morbidity was 15 per cent. Late radiation sequelae developed in 18 patients, including 15 patients with radiation proctitis (29 per cent), among whom 2 (4.6 per cent) suffered rectal ulceration and required diverting colostomy. Followup has been 2 years or longer (median 33 months) in 26 patients, of whom 22 (85 per cent) are free of disease. Three patients are living with osseous metastases or local disease and there has been 1 death of prostatic carcinoma, for an absolute 2-year survival rate of 95 per cent. Of the 7 patients with poorly differentiated tumor and of the 8 patients with positive pelvic lymph nodes 5 and 6, respectively, remain free of disease after a minimum 2-year followup. Potency has been lost in 20 per cent and reduced significantly in 30 per cent of the patients followed 18 months or longer. Prostatic biopsies on 28 asymptomatic patients 12 to 30 months after completion of therapy showed no tumor in 21 (75 per cent).

Adenocarcinoma↗

High-performance liquid chromatographic determination of ethmozin in plasma.

A sensitive, specific high-performance liquid chromatographic procedure was developed for the determination of plasma ethmozin levels. Basic plasma samples were partitioned with methylene chloride. The organic extract was washed with water and then evaporated to dryness under reduced pressure. The residue was redissolved in 0.2 ml of the mobile phase, consisting of hexane-tetrahydrofuran-methanol-water (66:27:6,30:0.7 v/v), and then chromatographed on a microporous silica column. With a variable-wavelength UV detector set at 268 nm, 10 ng of ethmozin/ml of plasma was measured. The utility of the method for human pharmacokinetic studies was demonstrated.

Chromatography, High Pressure Liquid↗

Experience with live donor nephrectomy.

We studied 100 patients undergoing nephrectomy for living related renal transplantation. after completion of tissue typing preoperative studies included urinalysis and culture, creatinine clearance determination, excretory urography and renal arteriography. Patient characteristics, preoperative test, surgical approach, complications, long-term followup and cost factors were reviewed. There was no mortality and morbidity was minimal except for wound complications. Renal function generally remained normal. Donor nephrectomy is a worthwhile and safe procedure with an acceptably low incidence of postoperative complications.

Adolescent↗

Determination of oxycodone in plasma and identification of a major metabolite.

An electron-capture GLC method is described for oxycodone and its major metabolite, noroxycodone, in plasma and urine. The method involves extraction of the two substances into benzene-isopropranol at pH 10.4, followed by back-extraction into 0.1 N HCl. The acid phase is washed with hexane and made alkaline prior to reextraction into benzene-isopropanol. The solvent is removed by evaporation, and the heptafluorobutyryl derivatives of the test substances are formed. After removal of excess reagent, oxycodone and noroxycodone are quantitated by GLC. The characteristics of both substances, with respect to plasma levels in dogs and analgesic activity in mice, are reported. Isolation of noroxycodone from human urine and its identification by TLC, GLC, and mass spectrometry are described.

Analgesics, Opioid↗

Quantitative determination of nalbuphine in plasma using electron-capture detection.

A procedure for the determination of nalbuphine in plasma is presented. The compound and an internal standard are extracted into benzene-2-propanol from plasma at pH 10.4, followed by back-extraction into 0.1 N HCl. After the acid phase is washed with benzene and the compound is reextracted into benzene-2-propanol, the heptafluorobutyryl derivatives are formed and determined using electron-capture GLC. The lower limit of sensitivity is approximately 0.5 ng/ml, and the upper limit of the linear dynamic range is greater than 50 ng/ml. Peak plasma levels of 50 and 150 ng were observed in two dogs 10 and 20 min, respectively, after subcutaneous administration of 1 mg of nalbuphine/kg. Nalbuphine was detectable in plasma 5 hr after administration.

Animals↗

Doxorubicin hydrochloride (adriamycin) in irradiated patients with advanced transitional cell carcinoma.

Twenty-five patients with advanced transitional cell carcinoma of the urinary tract were treated with doxorubicin hydrochloride (Adriamycin). Eight evaluable patients who received extensive external irradiation therapy and at least two doses of doxorubicin hydrochloride were studied to assess bone marrow toxicity and possible augmentation of radiation dermatitis. Myelosuppression was similar in both irradiated patients and those who received doxorubicin alone. None of the irradiated patients displayed skin augmentation reactions with doxorubicin. In the dose range used chemotherapy with doxorubicin did not appear to be particularly hazardous in irradiated patients.

Aged↗

Comparison of flutamide (SCH-13521) and diethylstilbestrol in untreated advanced prostatic cancer.

A double-blind study comparing the efficacy of flutamide (SH-13521) and diethylstilbestrol in 15 patients with advanced, previously untreated adenocarcinoma in the prostate in herein presented. Patients receiving diethylstilbestrol, 1 mg. daily, remained stable without evidence of progression of their disease for an average of 25.6 weeks while those receiving either high-or low-dose flutamide showed no objective progression for an average of thirty weeks. There were no complete remissions, and no signficant side effects were seen with either of these agents. In this small series of hormonally untreated Stage D prostatic cancer patients, neither agent displayed significant superiority.

Aged↗

Doxorubicin chemotherapy in advanced transitional cell carcinoma.

During the past year 25 patients with advanced transitional cell carcinoma were treated with intravenous doxorubicin hydrochloride (Adriamycin), 60 to 75 mg. per square meter of body surface area, every three weeks. Among the 19 evaluable patients, one partial objective remission lasting five months was observed. All 7 patients with bone pain had symptomatic relief and 12 patients had significant subjective improvement lasting an average of six-and-a-half months. Side effects were minimal and consisted of alopecia, mild leukopenia, and mild stomatitis; no significant cardiotoxicity was observed. Doxorubicin hydrochloride appears to have important antitumor activity in advanced urothelial tumors. Controlled clinical trials with this agent alone and in combined drug regimens are needed.

Aged↗

Vesicoureteral reflux in recurrent carcinoma of the bladder--implications for treatment and prognosis.

In an evaluation of the use of topical triethylenethiophosphoramide for therapy and prevention of recurrent multiple superficial transitional cell carcinoma of the bladder retrograde cystography was done. Unilateral or bilateral vesicoureteral reflux was demonstrated in 9 consecutive patients studied. Retrospective analysis uncovered 9 additional patients with bladder cancer and reflux. The discovery of vesicoureteral reflux prompts currently unanswerable questions regarding the etiology and pathogenesis of urothelial malignancy, as well as the role of topical chemotherapy in superficial tumors.

Adult↗

Serum immunoglobulins in genitourinary malignancies.

Serum concentrations of immunoglobulins G, A and M (IgG, Ig A and IgM) were measured by immunodiffusion in a control population of 58 patients and in 165 patients with cancer of the prostate, bladder, kidney or testis. Tumor patients were ranked according to clinical staging. In a smaller group of patients serum levels of IgE were measured by radioimmunoassay. IgG, IgA and IgM concentrations did not correlate with staging or the presence of malignancy. However, a statistically significant correlation between increased IgE levels and advanced bladder cancer (staged D1 and D2) stimulated us to study more patients with bladder tumors. In a subsequent group of 22 bladder tumor patients this trend could not be reproduced. IgE levels did not correlate with a history of allergy in any of the patients tested. Concentrations of immunoglobulins G, A, M and E seem to be unchanged in genitourinary malignancies, although their functional role here has not been assessed qualitatively.

Female↗

Pitfalls in clinical staging of bladder tumors.

Errors in clinical staging of bladder carcinoma occur in about 50 per cent of patients. Sources of error include (1) a variable assortment of diagnostic studies performed, (2) inexactitudes inherent in the diagnostic measures employed, (3) insufficient corroboration by surgical and pathologic staging, (4) the lack of a satisfactory means for detecting micrometastases, and (5) a generalized confusion regarding the multiple classifications available for clinical staging. More precise clinical staging will be influential in treatment decision-making and in prognosis. Minimum requirements for clinical staging of the primary tumor currently include complete examination, excretory urography, cystoscopy, bimanual examination under anesthesia, and transurethral resection or biopsy. Polycystography, triple contrast cystograpy and arteriography may be helpful occasionally to document muscle invasion. Pedal lymphangiography and lymphography can in selected cases be helpful in detecting otherwise silent nodal involvement in spite of its inability to demonstrate many primary or regional lymph nodes. Familiarity with the above diagnostic options and the advantages and limitations of each is essential for each physician caring for a patient with bladder carcinoma. Conversion to TNM classification for bladder carcinoma that is similar to that of the UICC seems appropriate (1) because of its more rational approach to extent of involement by primary tumor, lymph node and distant sites, and (2) in order for our western hemisphere urologists to communicate better with our colleagues from around the globe. Such a system is now under consideration by a subcommittee of the American Joint Committee on Staging and End Result Reporting.

Aged↗

Biotransformation of pravastatin sodium in humans.

Pravastatin sodium (PV) is a potent cholesterol-lowering agent that acts by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Biotransformation profiles of PV in pooled human urine, plasma, and feces from healthy male volunteers given single 19.2-mg oral or 9.9-mg iv doses of [14C]PV were determined by HPLC. The predominant drug-related component in urine, plasma, and feces corresponded to intact PV; in the pooled urine samples, PV constituted 29 and 69% of the radioactivity after the po and iv doses, respectively. The delta 4.5-3 alpha-hydroxy isomer of PV constituted 10% (po) and 2% (iv), and 6-epi-PV constituted 3% (po) and 1% (iv) of the urinary radioactivity. Negligible amounts of the lactones of PV or its isomers were detected in urine, plasma, or feces. At least 15 other metabolites were also present; none of these accounted for more than 6% of the total urinary radioactivity. For metabolite isolation, an aliquot of pooled urine samples, obtained after administration of the radioactive dose, was added as a tracer to urine samples obtained from healthy subjects after administration of single nonradiolabeled 40-mg oral doses of PV. Urinary metabolites were concentrated on an XAD-2 column, extracted with ethyl acetate, and purified by extensive preparative HPLC. In addition to isolation and identification of unchanged drug and the two isomeric metabolites described above, eight other metabolites were isolated and structural assignments were made based on HPLC, UV spectra, mass spectral analysis, and proton NMR.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗