Histology and histopathology Vol. 8, nº 1 (1993)
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- PublicationOpen AccessClinico-pathological correlations in meningiomas, a DNA and immunohistochemical study(Murcia : F. Hernández, 1993) Cruz-Sánchez, F. F.; Miquel, R.; Rossi, M.L.; Figols, J.; Palacín, A.; Cardesa, AntonioWe have studied 41 meningiomas classified histologically as benjgn, atypical or anaplastic. There were 26 females and 15 males and the mean age was 53 years. 36 tumours were supratentorial, 4 infratentorial and one spinal. Flow cytometry was performed on paraffin-embedded tissue using a selective staining technique for DNA. The ploidy index of DNA and percentage of cells in the S and G2/M phases were calculated. Results were correlated with clinical, histological and immunohistological data. 16/41 tumours . were found to be diploid, 17/41 aneuploid and 8/41 could not be analysed. Significant correlations were found between aneuploid tumours and some qualitative features such as recurrence, pleomorphism, high cellular density, mitotic activity and brain and soft tissue infiltration. A high proliferative index appeared to be associated with clinical aggressiveness. No particular correlation between the expression of cytokeratin and epithelial membrane antigen markers and flow cytometry was found. Our results suggest that DNA flow cytometry in meningiomas may be of value in predicting the behaviour of these neoplasms and confirm that epithelial pattern in meningiomas is not linked to increased anaplasia or poor prognosis.
- PublicationOpen Accesslmmunogold identification of the GH cells of goat in different physiological conditions(Murcia : F. Hernández, 1993) Sánchez, J.; Bernabé, A.; Serrano, J.; Gómez, S.; Navarro Cámara, José AntonioGrowth hormone-containing cells (GH cells) in the anterior pituitary gland of the female goat during anoestrus, pregnancy and lactation were identified by the immunogold complex technique combined with electron microscopy. In the three physiological stages analyzed, most of the GH cells were characterized by a round to oval or triangular shape and the presence of numerous spherical and electrondense secretory granules (300- 1,200 nm). Granules with the largest diameters were observed during the lactating stage. In these cells, the rough endoplasmic reticulum (RER) and Golgi complex (GC) were usually poorly developed. Also in lactating animals, a low number of GH cells with more highly developed RER and GC with a few small secretory granules (230-360 nm in diameter) were also observed. This structural configuration suggests that these cells are more active than those with a lower development of cytoplasmic organelles, although their low frequency does not support a considerable increase in hormonal synthesis and release during lactation in comparison with anoestrus and pregnancy stages.
- PublicationOpen AccessGonadotrophin-releasing hormone immunoreactivity in the brain of the tropical freshwater fish, Pygocentrus notatus (Teleostei-Characidae)(Murcia : F. Hernández, 1993) Cáceres-Dittmar, G.; Tapia, F.J.; Guerrero, H. Y.; Paiva, C. L.; Marcano, D.The distribution of GnRH in the brain of the teleost Pygocentrus notatus was demonstrated with the avidin-biotin peroxidase immunocytochemical method using highly specific antibody against synthetic mammalian GnRH. Optimal immunoreaction was obtained using: 1) Bouin's fluid for fixation; 2) repeated incubation with primary antiserum; 3) the use of a detergent in the dilution buffer; 4) the high sensitivity of the avidin-biotin immunoperoxidase method with the cobalt intensification of 3-3'diaminobenzidine tetrahydrochloride; and 5) the use of primary antibody with high specificity. GnRH-immunoreactive (GnRH-ir) in cells andlor axons was observed in al1 main brain regions. In the forebrain, GnRH-ir was located in a network extending from the caudal part of the olfactory bulb to the telencephalon. GnRH-ir fibres were also observed in the optic tectum, cerebellum and hypothalamus. Two groups of neurona1 cell bodies were identified. One group was located in the antero-ventral telencephalon corresponding to the nucleus olfactoretinalis. The second group was found in the rostrodorsal hypothalamus. No GnRH-ir material was detected in the pituitary gland, thus confirming the results of previous studies on brain GnRH-ir distribution obtained by radioimmunoanalysis in this species. These results demonstrate a high degree of similarity between the GnRH systems of P. notatus and other teleost species.
- PublicationOpen AccessQuantitative histochemistry of phosphorus in the vestibular gelatinous membrane, an electron probe X-ray microanalytical study(Murcia : F. Hernández, 1993) López-Escámez, J. A.; Crespo, P. V.; Cañizares, F. J.; Campos, AntonioElectron probe X-ray microanalysis was used to study the phosphorus concentration in the otolithic gelatinous membrane of the saccule and the utricle with scanning electron microscopy. The otolithic membranes were plunge-frozen in liquid N2 and freeze-dried. Quantitative analysis was carried out with an energy dispersive detector using the peak-to-background ratio method and different concentrations of KH2P04 salts dissolved in dextran solutions. The otolithic gelatinous membrane consists of a 25- 30 pm-thick layer overlying the cilia of the hair cells. Elements detected in the gelatinous membrane are : Na, P, S, CI, K and Ca. Although Student's t-test did not show significant differences between saccular and utricular concentrations of phosphorus, the distribution of this element in the two organs was different. Regresssion analysis established that the concentrations of phosphorus in the saccular and utricular gelatinous membrane were dependent. The regression equation was: y = 18.02x2 + 133.9 (r = 0.83, P < 0.05) where y is the concentration of phosphorus in the utricle, and x2 the concentration of phosphorus in the saccule. The findings obtained in the present study could be related to structural differences in organic phosphate residues of the phosphoproteins associated to collagen, or to different polyphosphoinositide turnover rates in the cell membrane.
- PublicationOpen AccessInvolvement of neuropeptides in the regulation of growth, structure and function of the adrenal cortex(Murcia : F. Hernández, 1993) Malendowicz, L.K.Current data on the influence of neuropeptides on the growth, structure and function of cells comprising the hypothalamo-pituitaq-adrenal axis were presented and discussed. The action of vasopressin, oxytocin, neurotensin, bombesin, neuropeptide Y, substance P and VTP have been evaluated. The hypothesis has been introduced that in vivo effect of some neuropeptides on the structure and function of the adrenal cortex is mediated by vasopressin.