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  • 1995-1999
  • 1990-1994  (3)
  • Testis  (2)
  • Cell & Developmental Biology  (1)
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 191 (1991), S. 261-279 
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The structure of the human caput epididymidis was examined by gross morphological and light and electron microscopic techniques. There were at least seven types of tubules, each characterized by a different epithelium. These tubules were connected with one another by at least eight types of junctions to form a network. Most of the caput epididymidis was composed of efferent ducts. Within these, five types of tubules, each with a different ciliated epithelium, were found in different regions; and four types of junctions between the efferent ducts and the epididymal tubule were observed. The efferent ducts left the testis, initially as parallel straight tubules containing both ciliated and non-ciliated cells in an epithelium of irregular height. Each efferent duct then coiled tortuously into lobules that folded over one another. These efferent ducts then branched out as thin tubules to join a network of dark tubules which were lined by a regular epithelium containing prominently vacuolated, nonciliated cells. These tubules anastomosed via common cavities characterized by a ciliated cuboidal epithelium and sometimes joined tubules exhibiting a non-vacuolated ciliated epithelium. The latter, as well as typical efferent ducts, made connection with the epididymis proper in both end-to-end and end-to-side junctions. In the more distal junctions with the epididymis, the efferent ducts joined to a transitional epididymal ductule before joining to the side of the epididymis proper. Post-junctional epithelia in the beginning of the epididymis occasionally contained patches of cells characteristic of efferent ducts. Tall cells with long stereocilia constituted a discontinuous “initial segment”-like region of the epididymis. This is the most detailed study so far of the epithelia and the tubule organization in the caput epididymidis of any species, and most of the results are reported for the first time for the human. Although the pattern of the tubule network resembles that of some domestic species, the rich variety of epithelia has not been appreciated before.
    Additional Material: 35 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 267 (1992), S. 209-214 
    ISSN: 1432-0878
    Keywords: Testis ; Sulfhydryl oxidase ; Hypospermatogenesis ; Sertoli cell integrity ; Immunocytochemistry ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Sulfhydryl oxidase (SOx) immunoreactivity was investigated in the seminiferous epithelium of human biopsy material from the testes of 33 adult men with disturbed fertility. SOx immunoreactivity was expressed in normal seminiferous epithelium in type-A spermatogonia (27±4% of all spermatogonia) (n=4), in spermatocytes and round spermatids. Mature spermatozoa as well as Sertoli cells were unlabelled. within the interstitium, Leydig cells were immunopositive. In biopsies of oligozoospermic men showing hypospermatogenesis (n=24), an increase in labelled spermatogonia up to more than 90% was observed in biopsies, where seminiferous epithelia revealed only spermatogonia and Sertoli cells. Within the group of oligozoospermic patients there was a significant increase of labelled spermatogonia from 43±13% (〉20 mill/ejaculate) (n=7) to 55±16% ( 20 and 〉20 mill/ejaculate) (n=6) to 68±8% (〈5 mill/ejaculate) (n=11) and a significant (P=0.01) decrease of score count from 7.0±2.7 to 2.0±1.8. In this group the increase of labelled spermatogonia was correlated with sperm concentrations in the ajaculate (correlation coefficient: r=-0.6). In biopsies of azoospermic patients showing maturation arrest at the level of spermatocytes or spermatids (n=5) the percentage of labelled spermatogonia was within the range of 24% to 59%. Immunoreactivity in Sertoli cells was only found in single degenerating cells and in tubules showing Sertoli Cell Only Syndrome (SCO) without lumen formation. Sertoli cells within immature seminiferous cords were immunonegative, indicating that Sertoli cell SOx immunoreactivity is rather a sign of physiological alterations in degenerating cells than dependent on the stage of differentiation. Leydig cells did not show changes of immunoreactivity in any biopsy. It is concluded that SOx expression in spermatogonia may serve as a marker for spermatogenic efficiency.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 266 (1991), S. 23-28 
    ISSN: 1432-0878
    Keywords: Testis ; Spermatogenesis ; Leydig cells ; Sulfhydryl oxidase ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Sulfhydryl oxidase (SOx) is an enzyme that catalyzes the oxidation of sulfhydryl compounds. It is present in mitochondria of certain testicular cells at specific stages of functional activation. In the mature human testis moderate SOx immunoreactivity is found in Leydig cells, and lacking in Sertoli and in peritubular cells. The Adark spermatogonia usually contain immuno-reactive mitochondria, while in Apale spermatogonia immunoreactivity is mostly low. In stage V of spermatogenesis, Apale spermatogonia were found containing immunoreactive material. Leptotene (stages IV and V) and zygotene (stage VI) primary spermatocytes display a moderate immunoreaction. It is strongest in pachytene spermatocytes of stages I–IV, decreases in stage V, and is low during diakinesis and in secondary spermatocytes. Late spermatids usually show a stronger immunoreactivity than early spermatids. At stage V of spermatogenesis the late spermatids contain only few immunoreactive particles. Spermatozoa are free of SOx-immunoreactive mitochondria. In residual bodies small amounts of SOx-immunoreactive particles are seen. Compared to rat and hamster testis, SOx immunoreactivity of the human testis is less clearly stage-dependent and it is not confined to certain germ cell stages. As deduced from the findings in patients with spermatogenic disorders, the SOx immunoreactivity of spermatogonia in human testis seems to be of diagnostic relevance.
    Type of Medium: Electronic Resource
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