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  • 1
    Electronic Resource
    Electronic Resource
    Morphometric analysis of human epidermis treated with testosterone and dehydroepiandrosterone in organ culture (1989)
    Springer
    Archives of dermatological research 281 (1989), S. 417-423 
    Details
    ISSN: 1432-069X
    Keywords: Androgens ; Epidermis ; Organ culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The influences of testosterone and dehydroepiandrosterone (DHA) on human epidermal differentiation in skin organ culture were studied with quantitative light and electron microscopic morphometric methods. The hormones had equal effects on the general tissue architecture at the concentrations of 10-7 mol/l: they had a negligible effect on the thickness of the vital and cornified layers of epidermis, and on the type of keratinization, but caused a significant increase in the number of granular cells. The electron microscopic stereologic analyses showed that testosterone did not alter the size of either vital or cornified epidermal cells. Neither did it influence the quantities of major keratinocyte organelles (keratin filaments, desmosomes, ribosomes, mitochondria) in the different epidermal strata. However, the amounts of keratohyalin granules and keratinosomes were significantly higher in testosterone-treated granular cells than in controls. Qualitative electron-microscopic analysis of DHA-treated skin showed a similar change in the amount of keratohyalin granules and keratinosomes. The present findings suggest that although androgenic hormones exert little or no direct anabolic effect on epidermis, they may modulate keratinocyte maturation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00455328
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  • 2
    Electronic Resource
    Electronic Resource
    Ultrastructural study of hydrocortisone action in cultured human epidermis (1982)
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 106 (1982), S. 0 
    Details
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Adult human skin was maintained in organ culture in a chemically defined medium without serum for up to 10 days. Under these conditions cultured epidermis revealed ultrastructural changes suggesting alterations in keratinization. Half of the newly formed stratum corneum became parakeratotic. The number and size of keratohyalin granules were reduced, and only few keratinosomes were present after the 5th day of culture.The effect of hydrocortisone at final concentrations of 10−5–10−9 mol/1 was studied by applying stereological techniques for electron microscopic morphometry on systematically sampled tissues. The volume densities of tissue components and cell organelles were assessed at three different strata of epidermis on the 5th day of culture. Changes of keratinization due to the culture conditions were partly reversed by the hormone, i.e. hydrocortisone increased the volume densities of keratohyalin granules, keratinosomes and tonofilaments. Minute effects due to hormonal action were seen on tissue components or the volume densities of other cellular organelles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2133.1982.tb00903.x
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  • 3
    Electronic Resource
    Electronic Resource
    The influence of steroidal and nonsteroidal estrogens on the 5α-reduction of testosterone by the ventral prostate of the rat
    Amsterdam : Elsevier
    Journal of Steroid Biochemistry 35 (1990), S. 249-256 
    Details
    ISSN: 0022-4731
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0022-4731(90)90281-V
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  • 4
    Electronic Resource
    Electronic Resource
    47. Role of mesenchyme in the early cytodifferentiation of human prostate
    Amsterdam : Elsevier
    Journal of Steroid Biochemistry 11 (1979), S. xxv 
    Details
    ISSN: 0022-4731
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0022-4731(79)90411-4
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  • 5
    Electronic Resource
    Electronic Resource
    Studies on the mechanism of testosterone action on glucose metabolism in the rat ventral prostate
    Amsterdam : Elsevier
    Journal of Steroid Biochemistry 6 (1975), S. 1405-1413 
    Details
    ISSN: 0022-4731
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0022-4731(75)90077-1
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  • 6
    Electronic Resource
    Electronic Resource
    An attempt to simulate junctional epithelium of human gingiva in vitro (1983)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of periodontal research 18 (1983), S. 0 
    Details
    ISSN: 1600-0765
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Pieces of human masticator mucosa were maintained in a Trowell-type organ culture. The explants were placed on their side on either microporous filters or decalcified dentin matrix slices. The presence of serum in the culture medium enhanced epithelial outgrowth (epibolus) from the explants. The epibolus grew longer in contact with the substratum than along the free connective tissue surface of the explant.When grown on microporous filters, the flow of migrating cells was directed between the explant and substratum. As a sign of epithelial attachment to the filter, a structure morphologically similar to basal lamina and hemidesmosomes was seen. The decalcified dentin matrix, however, caused the epithelial cells to migrate outwards from the explant. The explants became loosely attached to the matrix. Although some electron-dense material was secreted into the contact area, a typical basal lamina was not seen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0765.1983.tb00365.x
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  • 7
    Electronic Resource
    Electronic Resource
    Development of human fetal prostate in culture (1981)
    Springer
    Urological research 9 (1981), S. 89-98 
    Details
    ISSN: 1434-0879
    Keywords: Human ; Prostatic ; Differentiation ; Androgens ; Interaction ; Ultrastructural
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The direct influence of androgens on prostatic development was studied by culturing explants of urogenital sinuses of human embryos and fetuses aged 6 to 13 weeks in the presence of either 10-7 mol/l testosterone or dihydrotestosterone for 6 days. The differentiation of prostatic epithelial cells started both in control and androgen-treated explants in the ninth week, and androgens accelerated the differentiation of the secretory pathway organelles in the epithelial cells. The amount of granular endoplasmic reticulum and the number of Golgi complexes increased in the presence of androgens, especially in the older fetuses. Incipient secretory activity appeared in some cells during the culture and the differentiation occurred sooner in the androgen-treated explants than in the controls or in vivo. The differentiation and maintenance of the urogenital mesenchyme was also better in the presence of the hormone. The direct epitheliomesenchymal cell contacts seen earlier in vivo were also seen during the differentiation in vitro. These contacts may indicate an inductive role of the mesenchyme in the glandular morphogenesis. Androgens were not able to induce the epithelial differentiation in vitro before the first signs of mesenchymal differentiation were evident in vivo. The results suggest either that the mesenchymal changes are not solely determined by androgens or that the early explants may require additional factors for proper differentiation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00256682
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  • 8
    Electronic Resource
    Electronic Resource
    Biomarker Responses in Whitefish (Coregonus lavaretus L. s.l.) Experimentally Exposed in a Large Lake Receiving Effluents from Pulp and Paper Industry (1998)
    Springer
    Archives of environmental contamination and toxicology 34 (1998), S. 69-80 
    Details
    ISSN: 1432-0703
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Notes: Abstract. Physiological and biochemical biomarker responses were studied in juvenile whitefish (Coregonus lavaretus L. s.l.) exposed experimentally to effluent from the forest industry. The large study area (609 km2), Southern Lake Saimaa, in Southeast Finland, receives 330,000 m3 d−1 of biologically and 55,000 m3 d−1 of chemically treated effluents, discharged from two integrated elementary chlorine free (ECF) bleached kraft pulp and paper mills, from one ECF pulp mill, and from one mill producing unbleached pulp and cardboard. The assessment of exposure to effluent discharged from the mills was based on lake water chlorophenolics (CPs) and resin acids (RAs) measured in samples collected from the 22 experimental sites along the area. Despite the low levels of effluent constituents in the lake, they were still accumulated in detectable levels in fish bile, indicating an exposure to the bioactive compounds of effluents. In comparison to the reference area, a two- to four-fold increase in ethoxyresorufin O-deethylase (EROD) activity was observed in whitefish exposed in the vicinity (1–6 km) of all the mills. However, cytochrome P450 1A1 (CYP1A1) gene expression was increased in only one of the receiving areas, indicating higher sensitivity of the EROD activity in the present study. There were no statistically significant correlations between EROD activity and the ambient water concentrations of the CPs, the RAs, or effluent dilution expressed by water sodium concentration. Neither bile chlorophenolics nor bile resin acids showed a significant correlation with EROD. No significant changes in circulating reproductive steroids, 17β-estradiol and testosterone, in juvenile whitefish were observed. The vitellogenin gene was expressed in the vicinity of the pulp mill discharging the most wood-derived compounds, i.e. resin acids and wood-sterols, including β-sitosterol. No differences were observed in plasma immunoglobulin M, glucose, or lactate concentrations between the effluent sources.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002449900287
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  • 9
    Electronic Resource
    Electronic Resource
    Early cytodifferentiation of human prostatic urethra and Leydig cells (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 194 (1979), S. 429-443 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The ultrastructure of the urethral epithelium and mesenchyme of the 6- to 9-week-old human embryos was studied in order to reveal early morphological signs of prostatic development. The morphological changes of the urethral wall were correlated with the cytodifferentiation of the Leydig cells of the same embryos. Throughout the study the urethral epithelium had two or more layers of cuboidal cells. The ultrastructure of the cells was primitive and they did not achieve characteristics of the secretory prostatic cell. The surface cells had well developed apical junctions and slender cytoplasmic processes projecting into widened intercellular spaces appeared during the developmental period. The urethral mesenchyme showed the most salient changes. The mesenchymal cells adjacent to the urethral epithelium differentiated in the ninth week into fibroblast-like cells with an elongated shape and cytoplasmic processes. Granular endoplasmic reticulum appeared in the cytoplasm and collagen fibers were seen in the intercellular space. Mesenchymal cell processes contacting the continuous basal lamina under the epithelium were present. No direct epithelio-mesenchymal cellular contacts could be seen. The differentiation of the mesenchyme before the epithelial outgrowths suggests that the mesenchyme has an essential role in the glandular development.Electron microscopic study of the Leydig cells showed that the amount of agranular endoplasmic reticulum increased considerably in the ninth week. This agrees with earlier biochemical findings on the capability of Leydig cells to produce androgens by this time. The temporal relationship between the cytodifferentiation of Leydig cells and the urethral wall is consistent with the idea that in the human, fetal androgens induce prostatic development.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091940309
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  • 10
    Electronic Resource
    Electronic Resource
    Correlation of early cytodifferentiation of the human fetal prostate and leydig cells (1980)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 196 (1980), S. 263-273 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The ultrastructural differentiation of the human prostatic epithelium and mesenchyme was studied in early developing glands and correlated with the differentiation of the Leydig cells of the same individuals during the tenth to sixteenth weeks.After initial folding of the basal lamina, the epithelial cells began to migrate into the differentiated, condensed mesenchyme at the end of the 10th week, and in the 11th week some of the prostatic outgrowths acquired a lumen. The acinar and tubular epithelium in the fetal prostate remained stratified, and adult type simple epithelium was not seen during the period between the 10th and 16th weeks. As a sign of incipient secretory activity, a few epithelial cells became polarized, and secretion granules with flocculent or dense content appeared in the Golgi area and in the apical parts of the cells in the 13th week. Occasional direct epitheliomesenchymal cell contacts were visible in association with the appearance of the secretory activity. Two cell types, not seen in the normal adult prostate, appeared in the epithelium of the primitive glands. Their nature and role in the glandular morphogenesis are not clear.During this time, the ultrastructural differentiation of the Leydig cells continued and their size and number increased. They occupied almost the whole in terstitium by the time secretion granules appeared in the prostatic cells. These findings support the current notion that androgens secreted by Leydig cells are the major regulators of prostatic development in man.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091960302
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