Histology and histopathology Vol. 5, nº 4 (1990)

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http://hdl.handle.net/10201/177434

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Histogenetic evolution of bovine gastric compartments during the prenatal period
(Murcia : F. Hernández, 1990) Vivo, J.; Robina, A.; Regodón, S.; Guillén, M.T.; Franco, A.; Mayoral, A.I.
In order to carry out this study, 62 embryos and fetuses of Friesian cows were used, and every stomach was dissected and subjected to the usual laboratory procedures. After obtaining each preparation all the histological and metrical changes that took place in the wall of the viscus during its development are described. The compartments are histologically differentiated into three stages: in the first one there is no compartment differentiation: in the second one, the rumino-reticulum, omasum and abomasum have differentiated; and in the third one every compartment is differentiated. In group 16, (78 days of gestation), a decrease in thickness of the muscular layer of all compartments, parallel to the histological differentiation has been observed.
Open Access
Scanning electron microscopy of swine lymphoid organs
(Murcia : F. Hernández, 1990) Ramos, José; Ramis, Antonio J.; Rabanal, Rosa M.; Marco, Alberto; Domingo, Mariano; Ferrer, Luis M.
The aim of this investigation was to study by scanning electron microscopy the structure of several swine lymphoid organs (lymph nodes, Peyer's patches, and tonsil). Two groups of animals were used: sixmonth- old pigs and six- to nine-day-old piglets. Samples were jet-washed to eliminate most free cells in order to observe the reticular framework of these organs more clearly. Peyer's patches in piglets showed two types of villi. In one of them the cellular types were absorptive cells and goblet cells. The second type of villi were shorter and wider, with M cells characterized by presenting long, thick microvilli over their surfaces. Peyer's patches of pigs did not show this second type of villi but were usually covered by absorptive villi. The soft palate tonsil was similar in both groups of animals with its surface epithelia1 cells full of microfolds, partially and frequently obscured by microorganisms. The appearance of the surface epithelium in the same crypt was different depending on the area. There was a large number of holes through which cells apparently passed towards the crypt lumen. The medulla in the lymph nodes was at the periphery and showed a dense reticular framework. Cortex-like lymphoid tissue was formed by lymphoid follides and diffuse lymphoid tissue with high endothelid venules and lymphatic sinuses. The serosal surface of lymphoid organs was formed either by a typical mesothelial cell layer (small intestine) or by loosely arranged connective fibers (lymph nodes).
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Haemangioblastoma, Histological and immunohistological study of an enigmatic cerebellar tumour
(Murcia : F. Hernández, 1990) Cruz-Sánchez, F. F.; Rossi, M.L.; Rodríguez-Prados, S.; Nakamura, N.; Hughes, J.T.; Coakham, H.B.
Paraffin-embedded blocks of 36 cerebellar haemangioblastomas were reacted with a panel of antibodies including glial fibrillary acidic protein, vimentin, epithelial membrane antigen, cytokeratin, Factor VIII, a neuroendocrine marker and with Ulex europaeus. agglutinin The main histological features, apart from the characteristic large abnormal vessels, were a prominent reticulin network, a cystic architecture and cellular and nuclear polymorphism. Two cell types were identified: endothelial and stromal. Twenty tumours were positive for glial fibrillary acidic protein because of included or reactive astrocytes as well as positive stromal cells. Vimentin was positive in all tumours with a diffuse distribution and a somatic pattern; blood vessels, stromal cells and reactive astrocytes were strongly positive. Factor V111 and Ulex europaeus agglutinin reactivity were present in a similar pattern of staining in endothelium and in five cases there were stromal cells that were positive with the latter. We were not able to ascertain the histogenesis of the stromal cell, which remains enigmatic.
Open Access
Results and histological development of various surgical techniques for correcting eversion of the third eyelid in dogs
(Murcia : F. Hernández, 1990) Mañé, M.C; Vives, M.A.; Barrera, R.; Bascuas, J.A.
An experimental study was made of 20 dogs in order to compare various surgical techniques used to correct eversion of the third eyelid, namely resection of most of the cartilage, resection of the central portion of the cartilage, and cartilage homotransplantation. An analysis was made of histological results obtained 45 days after operation, the most satisfactory result being recorded for homotransplantation of the third eyelid cartilage.
Open Access
Sites of lymph follicle formation in the draining popliteal lymph nodes of mice locally injected with antigenic and mitogenic substances
(Murcia : F. Hernández, 1990) Hee Kyung Ahnl; Hajime Hoshi; Kaeko Horie; Hidetsugu Nagata
Our previous studies showed that some antigenic and mitogenic substances, when locally injected into mice, efficiently produced new lymph follicles outside pre-exisiting follicles in draining lymph nodes, whereas others had virtually no effect. In the present experiments, young adult male mice were injected with several antigens and mitogens in the rear footpad, and the number and development sites of newly produced lymph follicles in the draining popliteal nodes were studied using serial sections of the nodes obtained between 5 and 21 days after injection. In the unstimulated state, each popliteal node contained a limited number of lymph follicles which mostly lay in a portion of the peripheral cortex overlaying the deep cortex (this portion is referred to as the PCOU), whereas a portion of the peripheral cortex extending beyond the deep cortex (referred to as the PCBU) was underdeveloped with only occasional follicles. Mice treated with soluble PHA or fluid tetanus toxoid developed germinal centers in association with existing follicles but failed to produce new follicles. The PCBU of the draining nodes remained underdeveloped, and the number and distribution pattern of lymph follicles within a draining node were comparable to those in the control node. Animals treated with LPS (50 pg). Con A, alum-precipitated PHA or alum-precipitated tetanus toxoid produced significantly large numbers of new follicles outside pre-existing follicles in the draining nodes, the new follicles produced in the PCBU being generally more numerous than those in the PCOU. In these draining nodes, the peripheral cortex, comprising a number of follicles, was found to overlie the deep cortex and extend beyond the deep cortex towards the hilar region. In animals given a less effective stimulant, such as ferritin or a smaller dose of LPS (10 pg), the draining nodes produced a relatively small number of new follicles, most of which were formed in the PCBU. The present results indicate that in the mouse popliteal node, the PCBU is morphologically underdeveloped under normal conditions. but develops lymph follicles in response to exogenous stimuli more readily than the PCOU, and that substances efficient in inducing follicle formation can be regarded as capable of stimulating the development of the peripheral cortex.

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