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  • 1
    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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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 288 (1997), S. 539-544 
    ISSN: 1432-0878
    Keywords: Key words: Testis ; hsp60 ; Infertility ; Spermatogonia ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The immunohistochemical localization of heat-shock protein 60 (hsp60) was investigated in testicular biopsies obtained from 121 adult men with disturbed fertility. In normal unaffected tubules, hsp60 immunoreactivity was localized to spermatogonia, primary spermatocytes and Sertoli cells. In spermatogonia, cytosolic and mitochondrial labelling could be differentiated. In general, the number of stained spermatogonia decreased with the loss of spermatogenic function. A significant (P〈0.01) reduction of stained spermatogonia was observed in testes with maturation arrest of spermatogenesis at the level of primary spermatocytes (30.2±21.6%) compared with testes exhibiting normal spermatogenesis. In addition, the decrease in the score correlated significantly with the diminution of cytosolic hsp60 immmunolabelling (coefficient r=0.25, P=0.03). There was a significant difference (P〈0.01) in the percentage of cytosolic-stained spermatogonia in testes with a score equal to or greater than 5 (14.7±9.8%) and a score less than 5 (8.9±6.9%). These observations suggest that a low level of hsp60 expression in spermatogonia may lead to a different pattern of protection, which in turn could be involved in low spermatogenic efficiency.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0878
    Keywords: Hypophyseal pars tuberalis ; (TSH), Thyrotropin ; Immunocytochemistry ; Photoperiod ; Phodopus sungorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Specific secretory cells in the hypophyseal pars tuberalis of Djungarian hamsters maintained under different photoperiods were investigated immunocytochemically by means of the colloidal gold technique using antibodies against rat thyrotropin (TSH). Secretory cells of animals kept under long photoperiods (LD16:8) showed positive staining of secretory granules (diameters 90–130 nm), whereas other intracellular structures were free of immunoreactivity. In animals kept under short photoperiods (LD8:16) secretory cells displayed increased numbers of secretory granules, but these organelles were devoid of immunoreactivity. In contrast, immunoreactivity of thyrotropes in the pars distalis did not differ between the two groups of animals investigated. The present results confirm earlier light-microscopical studies that in the pars tuberalis specific secretory cells show TSH-like immunoreactivity; however, they differ in their reactivity pattern from classical thyrotropes in the pars distalis.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 256 (1989), S. 183-190 
    ISSN: 1432-0878
    Keywords: Testis ; Spermatogonia, dislocation ; Compartmentation, pattern ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pattern of compartmentation of the seminiferous epithelium was investigated, using a lanthanum tracer technique, in human testicular biopsies of adult infertile men (age 27 to 44 years), where dislocation of spermatogonia from the basal lamina occurred. Spermatogonia type A and B were found in a two-or three-layered arrangement, in aberrant locations throughout the seminiferous epithelium, and in intratubular positions associated with fragments of Sertoli cell cytoplasm. Tracer impregnation was found around spermatogonia in a multilayered arrangement, indicating the extension of the basal compartment in a luminal direction. Single spermatogonia within the second or third layer of the seminiferous epithelium were regularly found to be surrounded by tracer. The junctional complex between the lateral membranes of adjacent Sertoli cells was devoid of tight junctions. Tracer penetration around spermatogonia in a more luminal position was prevented by intact Sertoli cell junctional complexes; tracer was also absent from intraluminal located spermatogonia associated with cytoplasmic fragments of Sertoli cells. The luminal extension of the basal compartment associated with the dislocation of spermatogonia clearly differs from the pattern of compartmentation during the movement of primary spermatocytes within undisturbed epithelium. There is a strong incidence of elevated serum levels of folliclestimulating hormone (〉7 U/l), indicating a suppression of Sertoli cell function; this may be the cause for the dislocation of spermatogonia and the changes of compartmentation.
    Type of Medium: Electronic Resource
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