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K J Tveter

Publications and source records attributed to K J Tveter.

At least 55 records · Page 3Linked to original sources

A randomized study on hormone-resistant prostatic cancer: estramustine phosphate versus low dose epirubicin with or without medroxyprogesterone acetate. A Norwegian multicenter study.

A prospective randomized study has been carried out in order to compare three different treatment modalities for symptomatic metastatic hormone-resistant prostatic cancer. A total of 79 patients were included. One group was treated with estramustine phosphate, another with Epirubicin plus Medroxyprogesterone acetate (MPA), while the third arm consisted of Epirubicin plus placebo. Best palliation was obtained by the combination of Epirubicin and MPA. This combination also seemed to be associated with the longest response duration.

Administration, Oral↗

Synchronous bilateral primary germ cell tumors in patient receiving estrogen therapy.

The present report concerns the occurrence of bilateral synchronous germ cell tumors in a sixty-eight-year-old man who received estrogen therapy for eleven months. Although there are previous reports on Leydig cell tumors developing in mice and man receiving estrogens, we have not found any connection between germ cell tumors and estrogen medication reported in the literature.

Aged↗

Calcified aortic sinotubular ridge: a source of coronary ostial stenosis or embolism.

This report reviews the findings in a calcified lesion involving the ridge at the junction of the sinus and tubular portions of the ascending aorta. The histologic features resemble the alterations in calcified aortic valve and do not exhibit those of atherosclerosis. The 37 cataloged cases are among the more severe and dramatic instances of a lesion more common than the cataloged number would suggest. The involved ridge may be related to any of the sinuses, although that related to the right aortic sinus is most commonly affected. Major complications include coronary ostial stenosis or embolism in an epicardial coronary artery. Ostial stenosis results either from overhanging of an ostium by the aortic lesion or from invasion of the wall of the aorta at the site of the arterial takeoff.

Age Factors↗

Long-term evaluation of aortic valvotomy for congenital aortic stenosis.

Aortic valvotomy (AV) for relief of congenital aortic stenosis (AS) is a palliative operation, and the purpose of this study was to determine the long-term benefit. After analyzing the symptoms at time of operation, 177 patients were separated by age at AV: newborns (1-14 days) 26, infants (2 weeks-1 year) 19, and children (greater than or equal to 1 year) 132. The newborn with critical AS typically presents with severe cardiac failure and the infant with moderate failure, whereas children may be asymptomatic. In the newborn group, final diagnosis has been made exclusively by noninvasive cardiac echogram since 1984. The presence of a hypoplastic left ventricle (HLV) and/or endocardial fibroelastosis (EFE) are the most important determinants of mortality. Operative survival was 11 of 13 (85%) in the newborn group if HLV/EFE were not present. No operative deaths for AV occurred after 1965 in children. When present, a preoperative electrocardiographic strain pattern resolved in 80% of patients. Of 33 reoperations (21%), four were required 1.0 (0.5-2) years later for newborns, five were required for infants 7.2 (1.5-20) years later, and 24 were required in children 11.0 (1.5-25) years later. These included 10 repeat valvotomies and 23 aortic valve replacements (AVRs) with a 91% survival rate. In summary, although valves of patients with congenital AS are morphologically abnormal, valvotomy is beneficial. It was found that (1) the operative survival rate has been 100% over the past 20 years for children and currently is greater than 80% in newborns in the absence of HLV/EFE; (2) reoperation rate is higher in newborns and infants; (3) benefit was shown by a sharp decrease in obstruction initially and improved ECG later; (4) long-term follow-up revealed a subset of patients who are asymptomatic and have only mild residual obstruction over 20 years after AV.

Actuarial Analysis↗

Metabolism of androgens in the seminal vesicles and the different lobes of the prostate in young mature rats.

Oxidation and reduction of 4-androstene-3,17-dione (androstenedione), 17 beta-hydroxy-4-androsten-3-one (testosterone), 17 beta-hydroxy-5 alpha-androstan-3-one (DHT), 5 alpha-androstan-3 alpha,17 beta-diol (3 alpha-A'diol) and 5 alpha-androstane-3 beta,17 beta-diol (3 beta-A'diol) were measured in homogenates from ventral (VP), dorsal (DP) and lateral prostate (LP), the coagulating gland (CG) and seminal vesicle (SV) of the intact sexually mature rat using NAD(H) or NADP(H) as cofactors. The specific activity of the various enzymes varied significantly between the different organs. 5 alpha-Reductase activity was highest in the DP and the CG, and undetectable in the LP. 17 beta-Hydroxysteroid oxidoreductase (17 beta-HSOR) activity was mainly confined to the LP. 3 alpha-Hydroxysteroid oxidoreductase (3 alpha-HSOR) activity was also highest in the LP. In the VP the highest 3 alpha-HSOR activity was recorded using NAD(H) as cofactor. In the other organs, similar or higher enzymatic activities were measured using NADP(H) as added cofactor. 3 beta-Hydroxysteroid oxidoreductase (3 beta-HSOR) activity was high in the LP and low or undetectable in the other tissues. Our results indicate that isoenzymes of 3 alpha-HSOR, 3 beta-HSOR and 17 beta-HSOR are present in the accessory sex organs of the rat.

17-Hydroxysteroid Dehydrogenases↗

Age dependent changes in androgen metabolism in the rat prostate.

Oxidation and reduction of androstenedione, testosterone, dihydrotestosterone (DHT), 5 alpha-androstan-3 alpha,17 beta-diol and 5 alpha-androstane-3 beta,17 beta-diol (3 alpha- and 3 beta-A'diol) were measured in homogenates from the ventral prostate (VP), dorsal prostate (DP), lateral prostate (LP), the coagulating gland (CG) and seminal vesicles (SV) in intact rats of different ages from young mature (3-6 months) to senescent rats (20-30 months). Some very old intact rats (30-32 months) were treated with testosterone in order to rule out the effect of this hormone on androgen metabolism. The enzymatic activities for young mature rats were significantly altered by increasing age, both with regard to differences between the various organs as well as differences in cofactor requirement. With increasing age, the specific activity of most enzymes gradually decreased. With testosterone as substrate, 5 alpha-reductase activity was significantly reduced in the old rats in all tissues studied and was undetectable in the oldest animals in the VP and the SV. On the other hand, 5 alpha-reductase could not be recorded in any tissue in any tissue in old rats when androstenedione was the substrate. 3 alpha-Hydroxysteroid oxidoreductase (3 alpha-HSOR) in the VP was the only enzyme which did not decrease in activity by increasing age. In the other lobes this enzyme activity decreased similar to 3 beta-hydroxysteroid oxidoreductase (3 beta-HSOR) and the 17 beta-hydroxysteroid oxidoreductase (17 beta-HSOR) activity. Administration of testosterone to old rats increased the specific activity of most of the enzymes studied.

3-Hydroxysteroid Dehydrogenases↗

A new dihydrotestosterone-forming index (DHTi).

A new index (DHTi) for the net formation of dihydrotestosterone (DHT) in a specific tissue is presented. This index is based on the main metabolic pathways forming DHT as well as on the main enzymatic activities removing DHT from the tissue. In the rat prostate, the DHTi is different in the various prostatic lobes. The index is highest in the ventral prostatic lobe, intermediate in the dorsal prostate and coagulating gland, and very low or undetectable in the seminal vesicles and the lateral prostatic lobe. With increasing age of the rats, the DHTi decreased. Testosterone treatment to old rats leads to an increased index.

17-Hydroxysteroid Dehydrogenases↗

A complete pyelo-uretero-vesical duplication.

A complete pyelo-ureteral duplication with a palpable pelvic mass giving urinary infection and a slight urinary incontinence is reported. An intravenous pyelography demonstrated that the renal calyces on the left side were reduced in number compared to those present on the right side. Renal resection and a pyelo-ureteral resection was performed. A brief survey of the embryological basis for this anomaly is presented.

Abnormalities, Multiple↗

Current approaches to research on prostatic function and pathology.

This article describes some of the techniques and approaches currently in use in prostatic research which hopefully will provide new information and perspectives on the etiology of prostatic pathology. These techniques include a variety of methods for visualizing and quantitating protein hormone receptors, protein electrophoresis of prostatic tissue and fluids for protein markers, cell separation of the different cell populations of the prostate so that their interaction can be evaluated, and tests for the influence of low molecular weight peptides on prostatic function. Examples of the type of information which can be derived from each of the approaches are included and discussed.

Adenylyl Cyclases↗

A systematic study of biochemical differences between the lobes of the rat prostate.

The present study constitutes a systematic search for biochemical parameters which could be used to monitor the isolated function of various prostate lobes and accessory sex glands in the rat. Various parameters were measured in the 105 000 X g supernatants of the ventral, lateral and dorsal prostate lobes, and in the coagulating glands and seminal vesicles. These included spermine, citric acid, acid phosphatase, fructose and zinc, as well as the pattern of proteins in both cytosols and secretions, which were determined using one dimensional SDS, polyacrylamide gel electrophoresis. The results suggest that several parameters can be used including: Ventral lobe--spermine or prostatein; Lateral lobe--zinc or a 15 000 dalton protein; Dorsal lobe--spermine or a 60 000 dalton protein; and coagulating gland--fructose.

Acid Phosphatase↗

Ileal ureter: current status.

Use of the ileum as a substitute for the ureter should be taken into consideration when urinary tract continuity cannot be restored by using urinary tract tissue. Another important indication for this procedure is recurrent renal calculi, to permit the free passage of stones. It is essential to reserve this operation for those patients whose renal function is relatively adequate. Chronic renal insufficiency with a serum creatinine level above 2.0--2.2 mg% is a contraindication for the operation. Another prerequisite for the operation is that the patient is able to empty his bladder; otherwise deterioration of renal kidney function may occur. The present article gives a review on the ileal ureter, with emphasis on the indications and operative technique.

Aged↗