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Biomedical subjects

M Nistal

Publications and source records attributed to M Nistal.

At least 55 records · Page 3Linked to original sources
PubMed1996

Fusocellular gonadal stromal tumour of the testis with epithelial and myoid differentiation.

We describe an unusual fusocellular gonadal stromal tumour with a benign behaviour in the left testis from a 16-year-old man. The neoplasm consisted of a non-encapsulated proliferation of irregularly arranged, fusiform cell bundles in fibrous connective tissue. The tumour cells contained a slightly infolded nucleus, some dilated rough endoplasmic reticulum cisternae, abundant filament bundles which connected to subplasmalemmal electron-dense bodies, pinocytotic vesicles and a discontinuous basal lamina. The intercellular spaces were narrow and the tumour cells were joined by desmosomes. These cells were immunoreactive for muscle actin, alpha-actinin and vimentin. Focal immunostaining for collagen type IV was observed around the cells. No immunoreactivity for keratins, desmin S-100 protein or XIIIa factor was found. The findings suggest that the tumour arose from the peritubular myoid cells.

Actins↗
PubMed1995

Large cell calcifying Sertoli cell tumour of the testis.

Five cases of large cell calcifying Sertoli cell tumour of the testis not associated with complex dysplastic syndromes are reported. The age of the patients ranged from 13 to 34 years and all the tumours were histologically similar, having large, isomorphic, non-mitotic, eosinophilic Sertoli cells with foci of calcification. Flow cytometry demonstrated the cells to be diploid or hypodiploid. All cases were positive for vimentin and focally positive for low molecular weight keratin. The present cases, together with a review of the 22 previously reported tumours, demonstrate that there are two clear cut types of large cell calcifying Sertoli cell tumour; those which are associated with complex dysplastic syndromes and which are bilateral and multifocal, and those which are not associated and are unilateral and focal. Prognosis in all of our cases was uniformly good despite invasion of the rete testis in two cases. It is considered that conservative resection of the tumour is the treatment of choice in cases not associated with complex dysplastic syndromes, since the malignancy rate is low.

Adolescent↗
PubMed1995

The origin of testicular microliths.

The origin and development of eosinophilic bodies and microliths were studied histochemically and immunohistochemically in 29 human testes from prepubertal and adult males with different diseases. Non-calcified and partially calcified eosinophilic bodies were found mainly in infants and children. Most of the eosinophilic bodies were apparently located within the seminiferous tubules, where they were surrounded by a double Sertoli cell layer. Serial sections revealed that these tubules were configurated abnormally, either displaying a spiral course or forming a cap-like structure over the eosinophilic bodies that were actually extratubular. Completely calcified bodies (microliths) were found mainly in testes from adult men. The microliths were intratubular and appeared to be surrounded by a double layer of Sertoli cells. Eosinophilic bodies stained with eosin, periodic-acid-Schiff and silver methenamine like the tunica propria of seminiferous tubules. The peripheral band showed immunoreaction to both anti-laminin and anti-type IV collagen antibodies, similar to the basal lamina. Microliths were von Kossa-positive and immunostained similarly to the eosinophilic bodies. The present results suggest that a microlith is formed as a small eosinophilic body in the tunica propria. Afterwards, the body increases in size by deposit of new substances and compresses the seminiferous tubule which forms a ring or cap around it. Thereafter, the body undergoes calcification and becomes a microlith which compresses the seminiferous epithelium and enters the tubule.

Adolescent↗
PubMed1994

Two cases of laryngeal leishmaniasis in patients infected with HIV.

A high incidence of visceral leishmaniasis has been documented in HIV-infected patients in endemic areas. In these patients, atypical locations and a chronic course of the disease are more frequent. Two AIDS patients with laryngeal leishmaniasis are reported. These cases are believed to be the first of this type documented in the literature. The possible pathogenic mechanisms of the disease are discussed. Infection with Leishmania donovani may eventually be described for every organ containing phagocytic cells.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Epithelial-myoepithelial tumor of the bronchus.

A primary bronchial tumor with a histological pattern similar to that of epithelial-myoepithelial tumor of the salivary gland is reported in a 55-year-old woman. The tumor was well delimited, although not encapsulated, and showed a polypoid growth. The tumor was composed of two types of neoplastic cells: epithelial cells displaying tubules and myoepithelial cells that either formed compact masses or surrounded the tubular formations. Immunohistochemical study confirmed positive immunoreaction to both high- and low-molecular-weight cytokeratins in the epithelial cells and positive immunoreaction to vimentin, S-100 protein, and myosin in the myoepithelial cells.

Bronchial Neoplasms↗
PubMed1993

Immunohistochemistry of the human ductus epididymis.

Our objective was to characterize epithelial cells, lamina propria, and sites of estrogen coupling in the caput, corpus, and cauda regions of the human epididymis using antibodies to cytokeratin types; epithelial membrane antigen; laminin; type IV collagen; vimentin; desmin-, and estradiol-receptor-related protein; and immuno-histochemical techniques. Principal cells immunostain by both AE1/AE3 antibodies (keratins 1-8, 10, 13-15, and 19) and anti-pan-keratin antibodies (keratin 5, 6, and 8). Immunoreactions to both anti-keratin antibodies increase from the caput to the cauda epididymis. The principal cells only immunostained by anti-keratin 19 antibodies in the cauda and showed no reaction to keratins 10 and 11. Basal cells and apical cells immunoreact to anti-AE1/AE3, antipankeratin, and antikeratin 19 antibodies, but not to antikeratin 10 and 11 antibodies, in all three epididymal regions. The principal cells immunoreact with epithelial membrane antigen antibodies in the stereocilia and subjacent cytoplasm. This immunostaining decreased from the caput to the cauda. Antivimentin antibodies stained the apical cytoplasm of principal cells and limited areas of both principal cells and basal cells. This immunoreaction decreased from the caput to cauda. Apical cells immunostained in the three regions. Immunoreaction to ER-D5 was moderate in the principal cells, basal cells, apical cells, and muscular coat cells in the cauda. The apical cells immunostained in the three regions. Antilaminin antibodies stained the epithelial basement membrane in the three regions. Type IV collagen was detected in the basement membrane as well as around the muscular coat cells in the three regions. Immunoreaction to desmin was intense in the muscular coat cells in the three regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Protein gene product 9.5 and ubiquitin immunoreactivities in rat epididymis epithelium.

A quantitative immunohistochemical study was performed of the distribution of protein gene product 9.5 (PGP, a soluble protein localized in neurons and neuroendocrine cells as well as in some non-nervous cells) and ubiquitin along the rat epididymis. In the ductuli efferents, PGP immunoreaction was observed in the whole cytoplasm of some columnar cells; a smaller number of columnar cells showed ubiquitin immunoreactivity with limited apical and basal cytoplasmic localization. In the proximal caput epididymidis, the whole cytoplasm of all columnar cells showed PGP immunoreactivity, ubiquitin immunostaining was negative in this region. In the middle and distal caput epididymidis and the distal cauda, the apical cytoplasm of some columnar cells and the whole cytoplasm of some basal cells showed immunoreactivity to PGP. In these regions, immunoreactivity to ubiquitin was positive in the supranuclear cytoplasm of some columnar cells but not in the basal cells. No immunoreactivity to PGP or ubiquitin was detected in the corpus epididymis and the proximal cauda. Double immunostaining revealed that all the epididymal ubiquitin immunoreactive cells were also PGP immunoreactive, whereas most PGP immunoreactive cells did not immunoreact to ubiquitin. In ubiquitin-PGP immunoreactive cells, the site of the PGP immunoreaction differed from that of the ubiquitin immunoreaction. PGP-ubiquitin immunoreactive cells also seemed to be immunoreactive to anti-AE1/AE3 keratin antibodies. The spermatozoal heads were immunoreactive to PGP antibodies in the epididymal regions from proximal caput to distal cauda but not in the ductuli efferents. The findings suggest that non-ubiquitinated PGP immunoreactive proteins are secreted in the epididymis, mainly in the proximal caput, and attach to spermatozoa.

Animals↗
PubMed1993

Cytophotometric DNA quantification in human spermatogonia of cryptorchid testes.

The DNA content of spermatogonia was studied by cytophotometric quantification in the testes of cryptorchid children and adults, as well as in age-matched control males. In most cases, the average DNA content of spermatogonia was significantly increased in the cryptorchid testes of children with uni- or bilateral cryptorchidism, as well as in the contralateral scrotal testes of children with unilateral cryptorchidism. In the group of adult men the average DNA content of spermatogonia in the testes was even more increased than in children. There were not significant differences between 4 and 14 years of age, between unilateral and bilateral cryptorchidism, or between cryptorchid testes and contralateral normally descended testes. The DNA content of spermatogonia in the surgically descended testes of 3 children who were re-biopsied 3-4 years after orchidopexy was similar before and after orchidopexy. These findings suggest that the spermatogonia of many cryptorchid males bear a congenital lesion.

Adolescent↗
PubMed1993

Enzymohistochemical and immunohistochemical study of the human efferent ducts.

An enzymohistochemical and immunohistochemical study of the efferent ducts was performed in normal adult men. The epithelium consists of two types of columnar cells: principal cells (PCs) and ciliated cells (CCs), and is surrounded by a lamina propria (LP) with cells arranged circularly (LPCs). Enzymohistochemical study revealed more intense activity of succinic dehydrogenase, NADP, and ATPase in the CCs than in the PCs. The LPCs also showed an intense reaction for NADP and ATPase. Acid phosphatase activity was only intense in the apical cytoplasm of PCs. Immunohistochemical study revealed that antibodies to oestradiol receptor-related protein (ER-D5) immunostained the PCs and CCs intensely and the LPCs weakly. AE1/AE3 antibodies (which stain keratins nos. 1-8 and 14, 15 and 19) immunostained the PCs intensely, but was negative in both CCs and LPCs. Antibodies to keratin Ks.4.62 (which stain keratin no. 19) immunostained PCs and CCs but not LPCs. Epithelial membrane antigen antibodies (EMA) immunostained the adluminal surface and apical cytoplasm of PCs. Anti-vimentin antibodies immunostained the cytoplasm of PCs and CCs weakly as well as isolated cells in the LP. Antibodies to desmin immunostained most LPCs. Antibodies to collagen IV immunostained the basal lamina and many extracellular spaces in the LP, mainly around the LPCs. The differences between the enzymohistochemical and immunohistochemical patterns of the efferent ducts and those of the epididymis may help to explain functional differences along the epididymis.

Adult↗
PubMed1993

Immunohistochemical and semiquantitative study of the apical mitochondria-rich cells of the human prepubertal and adult epididymis.

An immunohistochemical and semiquantitative study of the apical mitochondria-rich cells (AMRC) in the caput, corpus and cauda of the human epididymis from the fetal period to adulthood was performed on autopsy specimens from normal males without testicular or associated pathology. The immunohistochemical pattern of AMRC differed from that of the principal cells (PC). AMRC showed a more intense immunoreaction to several keratin types (AE1 and AE3 keratin complexes, and keratins 18 and 19) and to oestradiol-related protein receptors than did PC. In addition, immunostaining with antibodies to epithelial membrane antigen was intense in PC and weak in AMRC. Two immunohistochemical types of basal cells were observed: one was similar to the AMRC and the other to PC. PC and AMRC were already present in fetuses of 24-27 wk gestation. Basal cells were only occasionally observed at this age, but became much more numerous in the 28-33 wk fetuses. No changes in the immunohistochemical patterns of any of these cell types were found during infancy and adulthood. The numbers of PC per unit length of basement membrane were very similar in the 3 epididymal regions and at all ages studied. In all age groups, the number of AMRC decreased from caput to cauda epididymis. In the caput and corpus, the number of AMRC rose during the fetal period and the first 6 months after birth and thereafter decreased progressively during infancy and adulthood.

Adult↗
PubMed1992

The peritubular myofibroblasts in the testes from normal men and men with Klinefelter's syndrome. A quantitative, ultrastructural, and immunohistochemical study.

The ultrastructure and immunostaining with antibodies against actin, desmin, and vimentin were studied in the peritubular myofibroblasts of testes from normal men and men with Klinefelter' syndrome (KS). The seminiferous tubules were classified into five types (a-e), related to the progressive degree of sclerosis measured as thickening of the lamina propria. In control testes, only types a and b tubules were present, whereas the testes from men with KS showed types b, c, d, and e tubules. The ultrastructural study revealed abundant microfilament bundles with electron-dense bodies in the cell periphery of the myofibroblasts in a and b tubules. In c tubules, the microfilament bundles of the myofibroblasts were lacking in electron-dense bodies. Myofibroblasts in tubules d and e showed scanty microfilament bundles. Immunostaining of peritubular myofibroblasts with anti-actin antibodies was intense in tubule types a-c and scanty in types d and e. Immunostaining of myofibroblasts with anti-desmin antibodies was intense in tubule types a and b, and negative in types c-e. Immunostaining with anti-vimentin antibodies was weak in tubule types a-c and intense in types d and e. Quantitative study revealed that with the progression of sclerosis, the number and volume per cross-sectioned tubule of actin-containing cells and, mainly, desmin-containing cells decrease while the number and volume of vimentin-containing cells increase.

Actins↗
PubMed1992

Macro-orchidism: light and electron microscopic study of four cases.

A hormonal and quantitative light microscopy study of one man with macro-orchidism associated with mental retardation and fragile X chromosome (case no. 1) and three men with idiopathic macro-orchidism (cases no. 2 to 4) is reported. Hormonal study revealed slightly increased follicle-stimulating hormone serum levels in cases no. 1 to 3. The testes from cases no. 1 (orchidoepididymoectomy specimen) and 2 (testicular biopsy) presented interstitial edema and three different tubular patterns that were arranged in a mosaic-like manner. Type I tubules had an increased diameter (less than 220 microns), dilated lumen, and thin seminiferous epithelium usually consisting of Sertoli cells, spermatogonia, primary spermatocytes, and sometimes a few spermatids. Type II tubules had a normal diameter (180 to 220 microns) and germ cell development varied between complete spermatogenesis and Sertoli-cell-only tubules. Type III tubules had decreased diameter (less than 180 microns), atrophic seminiferous epithelium, and thickened tunica propria. The appearance of the nuclei of the Sertoli cells in the three types of tubules could be either mature or immature. Some of the mature Sertoli cells presented a granular cytoplasm. A few of these granular cells grouped together, forming nests that protruded into the tubular lumen. The testicular biopsies from cases no. 3 and 4 only presented type II tubules that contained both mature and immature Sertoli cells. Quantitative study revealed that the large testicular size was principally due to an increased tubular length in all four cases. Although the seminiferous tubule lesions and interstitial edema suggest an obstructive process, the testicular excretory ducts (studied in case no. 1) appeared normal or only slightly dilated. It is possible that the seminiferous tubule lesions (dilated lumen and germ cell depletion) might be secondary to the Sertoli cell lesions (granular cytoplasm and nuclear immature-like pattern.

Adolescent↗
PubMed1992

Testicular fibroma.

A testicular fibroma in a 67-year-old man is reported. The tumor presented with expansive growth and myxoid areas. Atypias were absent. Differential diagnosis was made with immunohistochemical techniques that are useful for the diagnosis of nonspecialized gonadal stromal tumors. The origin of the tumor was probably in the interstitial or peritubular myofibroblasts.

Aged↗