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Biomedical subjects

K Schwarz

Publications and source records attributed to K Schwarz.

At least 163 records · Page 9Linked to original sources
PubMed1987

Induction of estrogen-related hyperplastic changes in the prostate of the cynomolgus monkey (Macaca fascicularis) by androstenedione and its antagonization by the aromatase inhibitor 1-methyl-androsta-1,4-diene-3,17-dione.

The cynomolgus monkey was selected as an experimental model to investigate the role of estrogens in the pathogenesis of benign prostatic hyperplasia (BPH) because its prostate seems to be more like the human prostate than that of other primate species. The treatment of intact, adult animals with the aromatizable substrate androstenedione for 3 months resulted in no significant changes in prostate weight, but in microscopically clearly detectable estrogen-related hyperplastic changes, particularly in a marked smooth muscle activation. These effects were antagonized by simultaneous, subcutaneous treatment with the aromatase inhibitor 1-methyl-androsta-1,4-diene-3,17-dione (1-Methyl-ADD) and only partially reversed by oral treatment. The serum estradiol (E2) concentration, which was not significantly elevated after treatment with androstenedione in comparison to the control, was drastically decreased after subcutaneous treatment with 1-Methyl-ADD and moderately decreased after oral treatment. In conclusion, these results as well as the great anatomical and histological similarities between the prostate of the cynomolgus monkey and that of man indicate that it might be a suitable and interesting model for future BPH studies.

Androstenedione↗
PubMed1987

Effects of pentachlorophenol and some of its known and possible metabolites on different species of bacteria.

The antibacterial activity of pentachlorophenol and 35 of its known or possible metabolites against 30 different species of bacteria was tested. In comparison with pentachlorophenol, no increase of inhibitory activity was found for any of the chlorinated anisoles tested (except for pentachloroanisole against Streptomyces spp.), 2-chlorophenol, 2,6-dichlorophenol, 2,3,6- and 2,4,6-trichlorophenol, 2,3,5,6-tetrachlorophenol, tetrachloro-1,4- and -1,3-benzenediol (except for the 1,3-isomer against Streptomyces spp.), tetrachloro-1,3-dimethoxybenzene, and tetrachloro-1,3-benzenediol diacetate. Two chlorophenols, five dichlorophenols, four trichlorophenols, two tetrachlorophenols, and tetrachloro-1,2-benzenediol were more active than pentachlorophenol against some, but not all, of the strains tested.

Bacteria↗
PubMed1986

Development of a model for the induction of estrogen-related prostatic hyperplasia in the dog and its response to the aromatase inhibitor 4-hydroxy-4-androstene-3,17-dione: preliminary results.

Although the presence of the testes is an absolutely necessary prerequisite for benign prostatic hyperplasia (BPH) to occur, the role of androgens in the cause of BPH is still controversial. There are increasing signs for a decisive role of estrogens in that connection. We treated castrated beagle dogs of known age with androstenedione (an androgen that can be aromatized) and with the aromatase inhibitor 4-hydroxyandrostendione. Six or 9 months of treatment with androstenedione resulted in a BPH characterized by typical androgenic effects--ie, hyperplasia and hypertrophy of the epithelium--and by typical estrogenic effects--, stimulation of the stroma, especially of the smooth muscles, and cystic enlargement of the tubules. These estrogen-related effects could be clearly antagonized by the simultaneous treatment with the aromatase inhibitor 4-hydroxyandrostenedione. The hyperplastic effects on the epithelium were also partly antagonized by the aromatase inhibitor. Our preliminary results further strengthen the effectiveness of aromatase inhibitors as an alternative treatment of human BPH, which is thought to be predominantly a stromal disease.

Androstenedione↗
PubMed1985

Two CEA and three NCA species, although distinguishable by monoclonal antibodies, have nearly identical peptide patterns.

In perchloric acid extracts of normal lung and colonic tumors, 3 NCA molecules were identified by monoclonal antibodies that cross-reacted with CEA, which itself gave 2 bands in SDS-PAGE. The proteins had molecular weights of 50, 75 and 97 kd, while the 2 CEA molecules banded at 180 and 160 kd in SDS-PAGE. No MAb recognized only one molecule, with the exception of MAb 3/13 which precipitated solely the upper CEA band. Analysis of the biochemical relationship of the cross-reactive antigens showed that none of them contained any internal methionine. Furthermore, after digestion by thermolysin, the peptide maps of the immunoprecipitated molecules showed very close similarities, if not identity. When the cross-reactive and the CEA were compared, the only differences found were in the upper CEA band, which apparently lacked one hydrophobic peptide, while the 97 kd cross-reacting protein showed one extra peptide. We conclude from our results that CEA and the cross-reacting molecules are composed of nearly identical, small (i.e. less than 50 kd) polypeptide chains.

Antibodies, Monoclonal↗
PubMed1984

Research and development of infant formulae with reduced allergenic properties.

Infant formulae based on hydrolyzed proteins or elemental diets offer the best treatment of cow's milk allergy whenever exclusive breast-feeding is not possible. In situations with a family history of atopy, formulae using other protein sources such as soya or chicken meat can also be a good preventive measure. The food industry needs reliable research methods for the evaluation of every new option before considering clinical trials. Allergenicity of cow's milk proteins was evaluated by the induction of mouse monoclonal reagins and also by oral administration of milk preparations to mice and guinea pigs. Animals initially raised on commercial diets containing about 1% milk whey could not be sensitized. Maintenance of a milk-free diet from pregnancy until weaning, and feeding milk in a liquid form led to an optimal sensitization of the guinea pigs. These animals suffered systemic anaphylaxis and their sera sensitized skin in virgin hosts. Under optimal conditions, while giving liquid preparations to drink, a considerable proliferation of the milk flora occurred. As no mucosal alterations could be detected, primary gut damage due to infection was probably not the triggering factor for oral sensitization. Bacterial products (e.g., endotoxins, enterotoxins) could stimulate the gut response towards milk proteins, either due to an adjuvant effect or to increased mucosal permeability. Microbial contamination of milk is practically unavoidable and it can generally induce biologic activity, e.g., fresh milk regularly gives a positive limulus test for endotoxin by the time it is consumed or processed. Reduction of bacterial contaminants by milk protective factors might help to prevent oral sensitization.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Comparison of colon-, lung-, and breast-derived carcinoembryonic antigen and cross-reacting antigens by monoclonal antibodies and fingerprint analysis.

Using a set of monoclonal antibodies that recognize different antigenic determinants on CEA, we analyzed CEA and cross-reacting antigens in the PCA extracts of mammary, lung, and colonic tumors. We could show differences between colonic and lung tumor CEA and identify a molecule in a breast tumor PCA extract cross-reacting with a colonic tumor CEA that has the same molecular weight but is not identical with it. By fingerprint analysis of the CEA digested with thermolysin, we could demonstrate differences between the two lung tumor CEA bands and the colonic tumor CEA. The results could be supported by sequential digest with V8-protease. The MAb so far available cannot distinguish between colonic and lung tumor CEA and the two lung tumor CEA bands. No differences were found in the fingerprints of colonic tumor CEA after immunoprecipitation with the different monoclonal antibodies.

Antibodies, Monoclonal↗
PubMed1983

[New aspects of the Heidenreich and Beck perfusion method in urodynamics. I: Practical experience with a complex urodynamic work station].

122 patients with urinary incontinence of all degrees and 32 controls are investigated by means of a complex urodynamic unit constructed by the authors. Essential part is a robust selfmade three-canal-catheter of heatsealed angiographic material with an external diameter of 10 Charr., which undamagedly can be used at least forty times. The unit enables to do cystometries and simultaneous cystourethrotonometries with electromyography of pelvic floor and mictiometries. The investigations are possible at a normal expense in lying or sitting and all intermediate positions. Many urometric parameters had been determined with aid of perfusion uromanometry according to the principle of Heidenreich and Beck. New combinations had been elaborated. The functional length of urethra in stress profile, the maximal urethral closing pressure, the electronically registered urethral closure pressure, the depression factor and the stress quotient are of special importance. By means of these criteria the qualification of the apparently old fashioned perfsuion uromanometry for a modern urodynamic diagnosis could be demonstrated. The results are compared with those obtained with microtransducer technique.

Female↗