Histology and histopathology Vol. 7, nº 3 (1992)
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- PublicationOpen AccessA scanning and transmission electron microscopic study of the membranes of chicken egg(Murcia : F. Hernández, 1992) Tan, C.K.; Chen, T. W.; Chan, H.L.; Ng, L.S.Questions regarding the structure of the inner and outer shell membranes of the chicken egg were addressed in this study by correlating observations from light microscopy and scanning and transmission electron microscopy. The egg membrane had a limiting membrane, which measured .9 to .15 pn in thickness and appeared to be a continuous and an impervious layer, but the shell membrane did not. Under the SEM, each membrane was seen to be made up of severa1 fibre layers. In the tear preparations viewed under the SEM two layers were observed in the egg membranes and three to five layers in the shell membrane, with an apparent plane of cleavage between each layer. Each fibre was made up of a central core and an outer mantle layers. The central core was perforated by channels which measured .O8 to 1.1 1 pn in diameter and ran longitudinally along the length of the fibre. Between the mantle layer and the fibre core was a gap or cleft measuring between .O3 to .07pn. The diameter of the fibres of the inner layer of the egg membrane ranged between .O8 to .64pn, whereas those of the outer layer of the same membrane ranged from .O5 to 1.11 p.m. Fibres in the shell membrane ranged from . l l to 4.14 pm diameter.
- PublicationOpen AccessStudies on the interaction between titin and myosin(Murcia : F. Hernández, 1992) Wang, Seu-Mei; Chung-Jiuan Jeng; Mu-Chien SunThis study examines the interaction of titin and mysoin. In order to analyze the domains of myosin contributing to the binding for titin, we conducted a solid phase binding assay. Different portions of mysoin (heavy chains, light chains and myosin fragments ) were coated on the microtiter wells and reacted with biotinylated titin. Then the binding of biotinylated titin to these polypeptides was detected by using the avidinbiotin- peroxidase method. The results demonstrated that light meromyosin and subfragment 1 were the major domains of myosin interacting with titin. Titin fragments obtained by trypsin digestion were allowed to react with myosin in an affinity column, and the bound fragments were isolated by an acidic elution. Immunoblot analysis of mysoin-bound titin fragments revealed that an A-band domain of titin was responsible for the binding of myosin. In addition, biotinylated titin labelled the outer A-bands and Z-bands in intact myofibrils, thus confirming the in situ binding of titin to myosin.
- PublicationOpen AccessRapid induction of atherosclerosis in rabbits(Murcia : F. Hernández, 1992) Saso, Y.; Kitamura, K.; Yasoshima, A.; Iwasaki, H. .; Takashima, K.; Doi, K.; Morita, T.Japanese white rabbits fed a restricted amount (100 glheadlday) of an atherogenic diet (AD) containing 0.2% cholesterol and 6% peanut oil showed mild and persistent hypercholesterolemia (338 I79 mgtdl). They developed atherosclerotic lesions 4 weeks after deendothelialization of aorta carried out at the 4th week of AD-feeding. This rabbit model of atherosclerosis has such advantages as being able to be produced in a short period and having similar biochemical and pathological characteristics with those in human atherosclerosis.
- PublicationOpen AccessBronchial-associated lymphoid tissue (BALT) response to airway challenge with cigarette smoke,bovine antigen and anti-pulmonary serum(Murcia : F. Hernández, 1992) Escolar Castellón, J.de D.; Escolar castellón, A.; Roche Roche, P.A.; Miñana Amada, C.The bronchial-associated lymphoid tissue (BALT) is a lymphoepithelial organ, related to the immune defence of the lung and to alveolar clearance, which changes size in certain states of disease. Changes in the size of BALT were quantified and compared, and Spearman's test was used to test the relation with the bronchial epithelium. A total of 180 rats were used, divided into 6 groups of 30 as follows: 1) untreated controls; 2) exposed to cigarette smoke for two months; 3) treated with antipulmonary serum three doses daily over five days; 4) exposed to cigarette smoke and treated with antipulmonary serum; 5) sensitized with bovine albumin and exposed to an environment containing this antigen for two months; 6) exposed to cigarette smoke and bovine albumin. The lungs were processed for histological study, and were stained with the PAS-Alcian blue method. The main left bronchi BALT was studied, and the following were quantified: Lymphatic area (LA), as a percentage of the lung surface occupied by BALT; the flat epithelium (FEp), as the length of bronchial epithelium anatomically related to LA, whose cells tend to adopt a flat shape; the Contact epithelium (Cep), as the length of bronchial epithelium which is in direct contact with the LA. A percentage count of bronchial cells was made in the following classifications: globet cells; globet cells stained with the PAS-Alcian blue method; flat cells; lymphoepithelium cells; columnar cells; and bronchial epithelium cells excluding the above two cell types. The most outstanding findings were that, in comparison with the controls, the FEp and CEp had increased in al1 the treated animals, and the CEp of the group treated with bovine albumin + cigarette smoke was the only one in which the difference was Offprint requests to: Dr. D. Juan de Dios Escolar Castellón, Facultad de Medicina, C./ Domingo Miral s/n, 50009 Zaragoza, Spain not significant (p > 0.05). The lymphatic area increased significantly (p < 0.001) in the groups treated with cigarette smoke, anti-pulmonary serum and cigarette smoke + anti-pulmonary serum, and decreased (p > 0.05) in the one treated with bovine albumin. Regression analysis gave good indices in general (Rho > 0.06), the exception being the group treated with cigarette smoke + ALS, in the relations CEpJFEp and CEpILA (Rho < 0.06). The globet ceiis decreased significantly in al1 the treated animals; however, the correlation between globet cells and the other variables did not give good indices (Rho > 0.06). Therefore, it is deduced that BALT can change shape in different conditions, FEp being the variable which increases most. The fa11 in globet ceiis is associated exclusively with the substances which were administered, since no relation was found between these cells and the morphological changes in the BALT.
- PublicationOpen AccessUltrastructure of murine cardiac ganglia in experimental Chagas's disease(Murcia : F. Hernández, 1992) Wong, W. C.; Tan, C.K.; Singh, M.; Yick, T. Y.Albino mice, infected with Trypanosoma cruzi (Tulahuen strain) were sacrificed on days 7, 9, 12, 14, 16, 18, 21, 32 and 39 following infection. Transmission electron microscopic examination of the cardiac ganglia revealed no ultrastructural change at day 7. At day 9 there was peri- and intraganglionic monocytic infiltration but parasites were absent. Between days 12 and 16 there was intense monocytic infiltration, with intra-ganglionic presence of parasites within fibroblasts, monocytes and macrophages. None were seen within capsular cells, endothelial cells, Schwann cells, statellite cells and ganglion cells. The Schwann cells and satellite cells, however, showed phagocytic activity. Satellite cells were also reactive with proliferative pseudopodia which encircled neuronal processes. By day 18, parasites were absent in the ganglia. But monocytes were still present up to day 39, some of them still engulfing satellite cell and neuronal processes. Satellite cells continued to be reactive and Schwann cells phagocytic. Ganglion cells remained normal throughout the experiment.The results suggest that infection of Schwann cells, satellite cells and ganglion cells may depend upon the tissue tropism of the strain of the parasite used and its concentration in the inoculum. The results are consistent with the view that any parasympathetic dysfunction in experimental Chaga's disease in the mouse may be of a transient nature.