Histology and histopathology Vol. 5, nº 3 (1990)
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- PublicationOpen AccessStudies with the Golgi method in central gangliogliomas and dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos disease)(Murcia : F. Hernández, 1990) Ferrer, I.; Martí, E.; Guionneti, N.; Bella, R.; Serrano, T.; Towse, J.; Conesa, G.; Isamat, F.The rapid Golgi method, combined with current optical and electronmicroscopica1 techniques, was used in three central gangliogliomas and in one dysplastic gangliocytoma of the cerebellum to study the morphology of ganglionic cells. Gangliogliomas were composed of bipolar, fusiform and radiate cells with dense core and clear vesicles in the perikaryon and cellular processes, the number of each cellular type varying from one case to another. These features, together with the fact that isodendritic neurons are considered to be phylogenetically old neurons, suggest that these tumours are composed of «primitive» neurons that are not homogeneous with regard to their morphology. In contrast, ganglionic cells in dysplastic gangliocytoma are huge cells with long, stereotyped neurites that establish unique asymmetric contacts with neighbouring perikarya and neurites by means of claw-shaped processes covered with synaptic buttons. These morphological characteristics are different from those of any other neuron of the CNS.
- PublicationOpen AccessEffect of ethanol on the cerebellar cortex of the chick embryo(Murcia : F. Hernández, 1990) Quesada, A.; Prada, F. A.; Espinar, A.; Genís-Gálvez, J. M.
- PublicationOpen AccessScanning electron microscopic study of natural killer cell-mediated cytotoxicity(Murcia : F. Hernández, 1990) Fernández-Segura, E.; García, J.M.The interaction between human natural killer (NK) celis and NK-susceptible target cells, as well as the mechanism involved in target cell lysis, were studied with scanning electron microscopy (SEM). Low density human peripheral blood lymphocytes, highly enriched with large granular lymphocytes (LGL), were used as effector cells, and K562-cells were used as NK-susceptible target ceiis. The surface features of LGLINK cells were examined under SEM. In the area of interaction, NWtarget-cell conjugates showed microvilli andor filipodia, and extensive areas of intercellular contact. In addition, the effector cells in some NWtargetcell conjugates were polarized toward the target cell. Changes in target cell surface features included loss of microvilli, large surface blebs and the appearance of small pore-like lesions on the cell membrane. Our findings show that target cell lysis occurred by apoptosis and plasma membrane lesions analogous to those seen during complement-mediated cytotoxicity.
- PublicationOpen AccessAn ultratructural and immunohistochemical study of extracellular matrix in meningiomas(Murcia : F. Hernández, 1990) Hisashi Nitta; Tetsumori Yamashima; Junkoh Yamashita; Toshihiko KubotaExtracellular matrix of meningiomas was studied by light and electron microscopy with the aid of immunohistochemical techniques. Special attention was paid to the distribution of type 1,111, IV, V collagens and laminin with a comparison between meningothelial and fibroblastic types. Connective tissue fibers and basement membrane were not found among the tumor cells in the meningothelial type, but were found in the fibroblastic type. The immunolocalizations were consistently demonstrated extracellularly, but were not within the cytoplasm. Type 1, 111 and V collagens were usually demonstrated in the fibrous septum in the meningothelial type, while they were localized among the tumor cells in the fibroblastic type. Furthermore, type IV collagen and laminin were demonstrated within the vascular walls or around the syncytium in the meningothelial type, while they were localized among the tumor cells in the fibroblastic type. In both types the expression of type IV collagen and laminin was closely related to the distribution of basement membrane. Although meningothelial and fibroblastic meningiomas showed quite different distribution of extracellular matrices, the profile of collagen types expressed by these two basic types was essentially the same. The cellular derivation of meningiomas was discussed with particular attention to the structure of human arachnoid villi and meninges.
- PublicationOpen AccessHuman pulmonary dirofilariasis, report of a new European case(Murcia : F. Hernández, 1990) Fabbretti, G.; Fedeli, F.; Alessi, A.; Boaron, M.; Salpietro, V.; Brisigotti, M.We report a new European case of pulmonary dirofilariasis occurring in an Italian patient. The paper emphasizes the peculiar pathological features of Pulmonary Dirofilariasis, that, on clinical and radiological grounds, closely irriitates primary or secondary neoplasms. The disease characteristically presents itrelf as a solitary subpleural coin-like lesion, histologically corresponding to a well demarcatec,, roughly spherical infarct, centered by a medium-sized thrombosed artery whose lumen contains the parasite, i.e. a Dirofilaria nematode.