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Biomedical subjects

W Voigt

Publications and source records attributed to W Voigt.

At least 91 records · Page 5Linked to original sources
PubMed1978

Inhibition of testosterone 5 alpha-reductase by and antiandrogenicity of allenic 3-keto-5,10-secosteroids.

(4R)-5,10-seco-19-norpregna-4,5-diene-3,10,20-trione(II), A 3-keto-5,10-secosteroid which is an irreversible inhibitor of delta 5-3-ketosteroid isomerase was tested for its possible antiandrogenicity in the hamster flank organ test. The organs of female animals topically treated with 4 microgram of testosterone propionate (TP) for 4 weeks enlarged in size and showed pigmentation resembling adult males. When compound II was applied concomitantly with TP, androgenic stimulation was completely blocked and the flank organs remained small like those of female animals. These results suggest that compound II may be a useful anti-androgen when applied topically. It may well act mainly by inhibition of the formation of 5alphs-reduced metabolites was markedly inhibited.

5-alpha Reductase Inhibitors↗
PubMed1978

Characterization of prostate carcinoma lines in the Copenhagen rat.

A comprehensive study of the R-3327 line of prostate adenocarcinoma of the Copenhagen rat was performed. This tumor, investigated in its histologic, endocrinologic, and immunologic aspects, was compared with a squamous cell prostate carcinoma derived from the R-3327. The two tumor lines differ in their rates of growth and in their androgen receptor contents, i.e., the adenocarcinoma is androgen dependent and grows slowly, whereas the squamous cell carcinoma has a rapid rate of growth and is androgen independent. A study of cell-mediated immune responses revealed that: 1) Nonspecific responses to mitogens in the blastogenic assay, as well as antibody-dependent cellular cytotoxicity, are enhanced in animals bearing tumors. 2) The R-3327 is immunogenic to its host as demonstrated by two parameters. 3) The antigens present in the squamous cell carcinoma are not recognized by lymphocytes of the animals bearing the adenocarcinoma, substantiating the specificity of the reaction. For these reasons, the system of R-3327 prostate adenocarcinoma provides a relevant model for the study of prostate cancer.

Adenocarcinoma↗
PubMed1977

Estrogen-binding protein from rat preputial gland: purification and characterization.

Cytosol from the rat preputial gland has been shown to contain a protein which binds both estrone and estradiol. The protein, after a 26-fold purification from the cytosol of female Sprague-Dawley rats, migrated as one band during electrophoresis in sodium dodecyl sulfate on acrylamide gel. The electrophoretic mobility indicated a molecular weight of 15,000. The association constant for estrone as determined by equilibrium dialysis was 1.2 X 10(7) M-1, while that for 17beta-estradiol was 3.3 X 10(6) M-1. Progesterone, cortisol, testosterone, or diethylstilbestrol did not bind to the purified protein, whereas 17alpha-estradiol or estriol bound only slightly. In the presence of retinoic acid, but not retinol, the binding of estrone was reduced. Optimum binding for estrone was at pH 6.5 to 8.5.

Animals↗
PubMed1977

[Utilization of inorganic sulfur sources by Staphylococcus aureus strains].

Staphylococcus aureus strains of different host-adapted variants (Meyer 1966) have been tested for their ability to use inorganic sulfur sources. All the 25 strains tested were able to utilize sodium sulfide as sulfur source in a medium similar to that described by Kloos and Pattee (1965). Using S. aureus strain 116/74 grown in a medium containing Na2-35S as the only sulfur source we studied incorporation and insertion of inorganic sulfide into sulfur containing amino acids. In disintegrated and fractionated cellular material we could find 35S labelled homocystine and methionine as major compounds, and cystine, cysteic acid, homocysteic acid, and beta-sulphopyruvate as minor compounds. The occurrence of homocystine and the sulfonic acids in bacterial proteins is rather uncommon.

Bacterial Proteins↗
PubMed1977

[Glycine dependence of Staphylococcus aureus strains].

Glycine dependent Staphylococcus aureus var. bovis strains (TSCHAPE and RISCHE 1971) were tested for their ability to grow on glycine containing and glycine deprived media. We observed glycine dependence only in minimal media. In complete media the strains grew in absence of glycine. Testing the ability of some glycine precursors we found that in minimal media glycine could be replaced by threonine and in some cases by serine. One mutant (Gly 100 Glyox.r.) was able to metabolize glyoxylate instead of glycine. Aspartic acid was metabolized in presence of glycine. Using 14C-aspartic acid we detected 14C-glycine and 14C-threonine. Presumably the bacteria metabolize aspartic acid to glycine via threonine.

Aspartic Acid↗
PubMed1977

Adenocarcinoma R-3327 of the Copenhagen rat as a suitable model for immunological studies of prostate cancer.

An experimental animal model for the study of host-prostatic tumor cell interactions has been described. R-3327, a line of prostatic adenocarcinoma of the Copenhagen rat, has been proven to be immunogenic to its syngeneic host as evidenced by two different in vitro cell-mediated immune assays. Specificity of the responses has been ascertained on the basis of absence of response: (a) of nonimmune lymphocytes to the R-3327 tumor antigen(s); (b) of R-3327 immune lymphocytes to several normal tissues including normal prostate; (c) of immune lymphocytes to unrelated squamous cell prostatic carcinoma of the Copenhagen rat. Furthermore, the presence of tumor has an effect in several nonspecific aspects of host response, inducing splenomegaly, heightened responses to nonspecific mitogens in lymphocyte transformation assay, and increased levels of killer cell action. Since there are many histological, biochemical, and functional analogies between this tumor line and human prostate carcinomas, this system appears to be suitable for immunological and possible immunotherapeutic studies of this type of neoplasia.

Adenocarcinoma↗
PubMed1977

[The endoscopic retrograde cholangiography (author's transl)].

This is a report of 760 endoscopic cholangiographic procedures. 76% of all examinations answered the given clinical problem. Prepapillar stenosis of the choledochus resulting from pancreatic diseases can be found in 35% of all pathologic findings. The diagnosis of a possible stenosis of the papilla Vateri is not facilitated by a retrograde cholangiographic examination. The intravenous cholangiogram with special regard to bile drainage seems to yield more information. A common drainage hindrance of the pancreatic and bile duct in connection with a stenosis of the papilla was shown in 26%. In 65% of patients with a postcholecystectomy-syndrome organic disease could be demonstrated which made a second operation necessary.

Adult↗
PubMed1975

5alpha-dihydrotestosterone-binding proteins and androgen sensitivity in prostatic cancers of Copenhangen rats.

A line (R-3327-A) of androgen-insensitive squamous cell carcinomas of the prostate of Copenhagen rats has been derived from an established line (R-3327) of androgen-responsive tumors R-3327 A tummors have a growth rate of approximately 10 times that of R-3327. The response of R=3327 A to hormonal environment has been determined by measuring the growth rate of the tumor transplanted to males, females, and castrated males. No great differences were observed. The metabolism of testosterone by tumore samples was studied following s.c. injections of the labeled steroid. The results show very little 5alpha-reduction of testosterone compared with that obtained in the prostate gland itself, as well as in the androgen-sensitive R-3327 tumors. A comparison of the presence of 17beta-hydroxy-5alpha-androstan-3-one-binding proteins in cytoplasmic extracts from both lines of tumors shows that the receptor proteins are present only in the androgen-sensitive R-3327 and not in the androgen-insensitive R-3327 A. The levels of the receptor proteins in R-3327 tumors are higher in tumors borne by male than by female animals, and castration of males decreases the amount of 17beta-hydroxy-5alpha-androstan-3-one binding.

Androgens↗