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Biomedical subjects

F Sinowatz

Publications and source records attributed to F Sinowatz.

At least 145 records · Page 8Linked to original sources

On the ultrastructure of the canine mammary gland during pregnancy and lactation.

During pregnancy and lactation marked changes are observed in the fine structure of the secretory cells in the Beagle mammary gland: especially pronounced are differences in cellular height, shape and size of the nuclei and distribution of mitochondria. In later stages of pregnancy a proceeding development of those cellular organelles involved in synthesis and extrusion of secretory material (i.e. rough endoplasmic reticulum, Golgi apparatus) can be observed. Myoepithelial cells which can be first discerned from secretory cells by ultrastructural features from day 40 on show only minor variations of their ultrastructure during pregnancy and lactation.

Animals↗

The lamina propria of the bovine seminiferous tubule.

The boundary tissue of bovine testicular seminiferous tubules exhibits remarkable regional differences at the level of the seminiferous tubule proper, as compared with its terminal segment. The basal lamina of the seminiferous tubule proper is multilayered and possesses knob-like protrusions. At the level of the terminal segment the basal lamina is highly specialized; in the region of the terminal plug candelabrum-like projections of the tubular basal lamina invade the bases of the modified supporting cells up to a depth of 3.5 microns. The adjoining surface of these supporting cells is densely studded with hemidesmosomes. The elongated peritubular cells are arranged in 3--5 concentric layers around the tubulus seminiferus proper but form a loose association at the level of the terminal segment. Where the terminal segment joins the testicular straight tubule, peritubular cells may assemble to constitute a contractile spiral. Elastic tissue is situated mainly subjacent to the tubular basal lamina and to a lesser degree between the peritubular cell layers. A peritubular space lined by endothelium-like cells may surround the seminiferous tubule proper and also the transitional zone of the terminal segment.

Animals↗

Histochemical localization of glycosidases in dog epididymis.

The histochemical localization of five glycosidases was studied in the epididymis of mature dogs. beta-Galactosidase showed a distinct to strong reaction in the epithelium of the ductuli efferentes and throughout the whole length of the ductus epididymidis. beta-N-Acetylglucosaminidase reactivity was weak in the initial segment, but increased significantly in the middle and terminal segment. The maximum beta-glucuronidase activity was found in the ductuli efferentes and in the initial segment. The alpha-mannosidase reaction was weak in all segments except the middle segment where a distinct activity was seen. With the method employed, no alpha-fucosidase activity could be detected. The physiological role of the glycosidases in the epididymis is discussed briefly.

Acetylglucosaminidase↗

[Histological localization of hydrolases in the epididymis of the dog].

Localization and activity of five hydrolases (alkaline phosphatase, adenosine triphosphatase, acid phosphatase, nonspecific esterase and leucylamino-peptidase) were evaluated histochemically in the epididymides of mature dogs. In the ductuli efferentes, cilia and apical parts of the epithelial cells displayed high activity of alkaline phosphatase and adenosine triphosphatase. Strong activity of acid phosphatase, nonspecific esterase and leucylamino-peptidase was present in the basal and supranuclear zones of the epithelium of the ductuli efferentes. Stereocilia of all three segments of the ductus epididymidis showed a high activity of alkaline phosphatase. Positive adenosine triphosphatase reaction was confined to the stereocilia of the initial segment. A complex pattern of acid phosphatase activity was observed in the middle segment. The subdivision of the middle segment in four subsegments was therefore suggested. In the epithelium of the initial segment only a few nonspecific esterase-positive cells were seen. The infranuclear and basal areas of the epithelium in the middle segment and the supranuclear zone of the terminal segment displayed distinct nonspecific esterase activity. The possible contribution of the hydrolases to the function of the epididymis is discussed.

Acid Phosphatase↗

[Enzyme histochemical studies on the epithelium of the epididymis of the tomcat (author's transl)].

The histochemical localization of some oxidoreductases was investigated in the epididymides of adult tomcats. Succinate dehydrogenase, lactate dehydrogenase, beta-hydroxybutyrate-dehydrogenase revealed their highest activity in corpus and cauda epididymidis whereas glucose-6-phosphate-dehydrogenase was strongest in the caput. The activity of the diaphorases and of cytochrome oxidase in the epididymal epithelium increased from caput towards the cauda epididymidis. The reaction for isocitrate dehydrogenase was distinct throughout the whole length of the ductus epididymidis. Our findings were compared with the biochemical results of other authors and the functions of the oxidoreductases in the epididymal epithelium were briefly discussed.

Animals↗

The uterovaginal sperm host glands of the quail (Coturnix coturnix japonica): an ultrastructural and ultracytochemical study.

Ultrastructural and ultrahistochemical studies were performed on the uterovaginal sperm host glands of the quail (Coturnix coturnix japonica). The proximal parts of the glandular necks are lined by a pseudostratified epithelium, consisting of high columnar ciliated cells and small, irregular shaped, basal cells. The true glandular epithelium is composed only of columnar cells with microvilli on their luminal end. A characteristic luminal feature is a large lipid droplet in the perinuclear region. In the subplasmalemmal region numberous tubular profiles are seen which could represent a cellular resorption system. To evaluate the absorptive capacity of the uterovaginal sperm host glands, tracer studies with HRP, ferritin, lanthanum and ruthenium red were undertaken. Since between 5 min and 3 h after injection no absorption could be found with the techniques mentioned, it is suggested that phagocytosis of spermatozoa by the glandular epithelium is not likely to occur.

Absorption↗

A histochemical study of glycosidases in benign prostatic hyperplasia and in prostatic carcinoma in the human.

In benign hyperplasia marked beta-glucuronidase and N-acetyl-beta-glucosaminidase activity was seen in the prostatic epithelium whereas the reactions for 5 other glycosidases were only slight or negative. The intensity of the reaction for the glycosidases in prostatic carcinoma was dependent upon the degree of the differentiation. The possible importance of glycosidases for the invasiveness of prostatic carcinoma is briefly discussed.

Adenocarcinoma↗

[Histotopography of glycosidases in the accessory glands of the boar before and after castration].

The histochemical distribution of six glycosidases (N-acetyl-beta-glucosaminidase, beta-galactosidase, beta-glucuronidase, alpha-galactosidase, alpha-mannosidase and alpha-fucosidase) was investigated in the prostate, glandula vesicularis and glandula bulbourethralis of castrated and non-castrated adult boars. The functions of the glycosidases in the male accessory sex glands of the boar and their androgen dependence are discussed briefly.

Animals↗

[Histotopics of lysosomal enzymes in the epididymis of the tom-cat (author's transl)].

The histochemical localization of 6 lysosomal enzymes was studied in the epididymis of adult tomcats. A weak to distinct reaction for acid phosphatase, leucyl-amino-peptidase and non--specific esterase could be observed in the epithelium of the ductus epididymidis in all three segments. Among the glycosidases, N-acetyl-beta-glucosaminidase displayed the strongest activity. alpha-man and alpha-fuc could not be demonstrated. For N-Acetyl-beta-glucosaminidase, beta-Galactosidase, acid phosphatase and non-specific esterase, an increase of enzyme activity from the initial segment towards the terminal segment was seen. Intracellularly, the maximum of enzyme activity of those four enzymes was supranuclear. This histochemically enstablished pattern of enzyme activity in the epididymis of the tomcat was compared with those of other mammals. The possible functions of enzymes in the epididymis was briefly discussed.

Acid Phosphatase↗

The subcellular distribution of zinc in dog prostate studied by x-ray microanalysis.

X-ray microanalysis of zinc in ultrathin sections of dog prostate was performed by electron microscope microanalysis using the potassium pyroantimonate method of preparation. Prostates of both mature and immature dogs were examined and the metal was found to be localised primarily in the nucleolus, nuclear chromatin and secretory granules of epithelial cells. Differences in zinc concentrations were observed between mature and immature tissues, particularly in the nuclear chromatin. The metal was also incorporated into epithelial secretions, lysosomes and fibromuscular stroma. Variable binding of zinc to tissue components was revealed by a combination of histochemical precipitation and subcellular analysis.

Animals↗

Hormonal effects on canine prostatic explants in organ culture.

Explants of canine prostate were cultured in a defined medium for periods of up to 5 days with and without added steroids. Testosterone and 5 alpha-dihydrotestosterone failed to maintain their histological integrity and induced a greatly increased formation of stromal elements. Epitestosterone and 5 alpha-dihydroepitestosterone were partially successful in maintaining epithelial height although secretory activity was not preserved. The only steroid that sustained epithelial height and secretory activity whilst keeping stromal growth at a minimum was 5 alpha-androstane-3 alpha, 17 alpha-diol. The three other epimeric androstanediols were ineffective.

Androstane-3,17-diol↗