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  • Central neurocytoma  (2)
  • Epididymal ultrastructure  (2)
  • Human  (2)
  • Man  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Pleomorphic pineocytoma with extensive neuronal differentiation: report of two cases (1994)
    Springer
    Acta neuropathologica 88 (1994), S. 448-453 
    Details
    ISSN: 1432-0533
    Keywords: Key words Pineal parenchymal tumors ; Pineocytoma ; Pineoblastoma ; Central neurocytoma ; Neuronal differentiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two pineal parenchymal tumors are presented, arising in a 54-year-old man and a 72-year-old woman; respectively. They showed isomorphic, cellular areas of small cells, often with characteristic pineocytomatous rosettes, and of medium-sized cells, as well as less cellular regions with highly pleomorphic, often ganglioid large cells. Immunohistochemistry disclosed extensive neuronal differentiation. There was intense positivity for neurofilament protein and microtubule-associated protein 2 in the pleomorphic areas and more variable expression in the isomorphic regions. Diffuse synaptophysin positivity was seen, accentuated along the borders of pleomorphic cells and in the rosettes, as well as diffuse interstitial and/or cytoplasmic expression of neuron-specific enolase, PGP 9.5 and tau. β-Tubulin III was detected in most cells and slight positivity was found in the rosettes. Expression of glial fibrillary acidic protein, however, was restricted to resident astrocytes and an interstitial network of processes. These neuronally differentiated pleomorphic pineocytomas underline the broad histomorphological spectrum of pineal parenchymal tumors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00389497
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  • 2
    Electronic Resource
    Electronic Resource
    Pleomorphic pineocytoma with extensive neuronal differentiation: report of two cases (1994)
    Springer
    Acta neuropathologica 88 (1994), S. 448-453 
    Details
    ISSN: 1432-0533
    Keywords: Pineal parenchymal tumors ; Pineocytoma ; Pineoblastoma ; Central neurocytoma ; Neuronal differentiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two pineal parenchymal tumors are presented, arising in a 54-year-old man and a 72-year-old woman; respectively. They showed isomorphic, cellular areas of small cells, often with characteristic pineocytomatous rosettes, and of medium-sized cells, as well as less cellular regions with highly pleomorphic, often ganglioid large cells. Immunohistochemistry disclosed extensive neuronal differentiation. There was intense positivity for neurofilament protein and microtubule-associated protein 2 in the pleomorphic areas and more variable expression in the isomorphic regions. Diffuse synaptophysin positivity was seen, accentuated along the borders of pleomorphic cells and in the rosettes, as well as diffuse interstitial and/or cytoplasmic expression of neuron-specific enolase, PGP 9.5 and tau. β-Tubulin III was detected in most cells and slight positivity was found in the rosettes. Expression of glial fibrillary acidic protein, however, was restricted to resident astrocytes and an interstitial network of processes. These neuronally differentiated pleomorphic pineocytomas under-line the broad histomorphological spectrum of pineal parenchymal tumors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00389497
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Protein transport to the epididymal lumen (1987)
    Springer
    Cell & tissue research 248 (1987), S. 527-530 
    Details
    ISSN: 1432-0878
    Keywords: Epididymal ultrastructure ; Peroxidase ; Protein transport ; Fluid-phase endocytosis ; Sprague-Dawley rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Experiments were performed to clarify the debate over the entry of circulating proteins into the epididymal lumen by use of the marker horseradish peroxidase (HRP). Epididymal tubules from the caput epididymidis of the rat were immersed in medium TC 199 containing HRP (3.5 mg/ ml) for 5 min to 3 h at 33° C. Sections were examined for the presence of tracer within the epithelial cells by electron microscopy. From 5 min to 3 h, vesicles containing peroxidase reaction products were found throughout the cytoplasm of the principal cells. Vesicles occurred close to both the basal and apical membranes, and many were found opening into the interstitial space and lumen, depending on the length of incubation. By 5 min labelled vesicles were infrequently found in the apical part of the cells. Reaction product was observed in the epididymal lumen adhering to the microvilli from 30 min of incubation onwards. At all periods of incubation peroxidase was present at the base of the epithelium and between the cells, but it was never found within the tight junctional complexes, and no reaction deposits were found within epithelial cells of tubules incubated in the absence of peroxidase. It is concluded that large molecules leaving the capillaries may enter the epididymal lumen in the caput by means of fluid-phase endocytosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216479
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  • 4
    Electronic Resource
    Electronic Resource
    Pattern of compartmentation in human seminiferous tubules showing dislocation of spermatogonia (1989)
    Springer
    Cell & tissue research 256 (1989), S. 183-190 
    Details
    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
    URL: http://dx.doi.org/10.1007/BF00224733
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  • 5
    Electronic Resource
    Electronic Resource
    Sulfhydryl oxidase immunoreactivity in seminiferous tubules of infertile men (1992)
    Springer
    Cell & tissue research 267 (1992), S. 209-214 
    Details
    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
    URL: http://dx.doi.org/10.1007/BF00302957
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  • 6
    Electronic Resource
    Electronic Resource
    Immunohistochemical distribution of sulfhydryl oxidase in the human testis (1991)
    Springer
    Cell & tissue research 266 (1991), S. 23-28 
    Details
    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
    URL: http://dx.doi.org/10.1007/BF00678707
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  • 7
    Electronic Resource
    Electronic Resource
    Distribution of heat-shock protein 60 immunoreactivity in testes of infertile men (1997)
    Springer
    Cell & tissue research 288 (1997), S. 539-544 
    Details
    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
    URL: http://dx.doi.org/10.1007/s004410050839
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  • 8
    Electronic Resource
    Electronic Resource
    Transcytosis in the epididymis studied by local arterial perfusion (1988)
    Springer
    Cell & tissue research 253 (1988), S. 631-637 
    Details
    ISSN: 1432-0878
    Keywords: Epididymal ultrastructure ; Transcytosis ; Protein transport ; Fluid-phase endocytosis ; Epididymal arterial perfusion ; Rat (Sprague-Dawley) ; Golden hamster ; Mouse (CB6/F1)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The transport of protein across the cells of the epididymal epithelium was studied using horseradish peroxidase. Transient vascular perfusion of the epididymis of the rat and golden hamster was achieved by pulsatile retrograde infusion into the testicular artery. Peroxidase was found in the interstitium and in the epithelium, located in vesicles, vacuoles and multivesicular bodies of principal, clear and apical cells. Similar findings were obtained in mice after systemic injection of the tracer. In the rat, discharge to the lumen was confirmed by the appearance of enzyme activity in luminal fluid from the caput epididymidis after local injection. The extent of transport amounted to no more than what has been considered leakage in physiological experiments, and the time-course of appearance complemented that found by electron microscopy. The level of transcytosis after pulsatile administration of peroxidase in vivo, as judged from the occurrence of tracer in the epithelium, was much less than that obtained during constant immersion in vitro. The protein was present in multivesicular bodies of principal cells and in vesicles of clear cells at short times after presentation in vitro, when it could not have arrived by endocytosis from the lumen. This suggests that routing of basal endocytic vesicles to the lysosomal apparatus occurs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219754
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