Histology and histopathology Vol. 7, nº 2 (1992)

Permanent URI for this collection

https://hdl.handle.net/10201/17704

Browse

Now showing 1 - 16 of 16

Open Access
Photoreceptor fine structure in the southern fiddler ray (Trygonorhina fasciata)
(Murcia : F. Hernández, 1992) Braekevelt, Charlie R.
The fine structure of the retinal lntroduction photorecéptors has been studied by light and electron microscopy in the southern fiddler ray or guitarfish (Trygonorhina fasciata). The duplex retina of this species contains only rods and single cones in a ratio of about 40:l. No multiple receptors (double cones), no repeating pattern or mosaic of photoreceptors and no retinomotor movements of these photoreceptors were noted. The rods are cylindrical cells with inner and outer segments of the same diameter. Cones are shorter, stouter cells with a conical outer segment and a wider inner segment. Rod outer segment discs display severa1 irregular incisures to give a scalloped outline to the discs while cone outer segment discs have only a single incisure. In al1 photoreceptors a non-motile cilium joins the inner and outer segments. The inner segment is the synthetic centre of photoreceptors and in this compartment is located an accumulation of mitochondria (the ellipsoid), profiles of both rough and smooth endoplasmic reticulum, prominent Golgi zones and frequent autophagic vacuoles. The nuclei of rods and cones have much the same chromatin pattern but cone nuclei are invariably located against or particularly through the externa1 limiting membrane (ELM). Numerous Landolt's clubs which are ciliated dendrites of bipolar cells as well as Müller cell processes project through the ELM, which is composed of a series of zonulae adherentes between these cells and the photoreceptors. The synaptic region of both rods (spherules) and cones (pedicles) display both invaginated (ribbon) synapses and superficial (conventional) synapses with cones showing more sites than the rods.
Open Access
Effects of omeprazole on the number of immunoreactive gastrin- and somatostatin-cells in the rat gastric mucosa
(Murcia : F. Hernández, 1992) Pawlikowski, M.; Karbownik, M.; Lewinski, A.; Pisarek, Hanna; Wajs, E.; Szkudlinski, M.
The effects of omeprazole - an inhibitor of gastric acid secretion - on gastrin (G)- and somatostatin (D)-cell density in the gastric antral mucosa epithelium in rats were examined, following a 5-day treatment. It was found that omeprazole increased the density of G-cells, whereas it decreased the density of D-cells. That effect was probably independent of hypergastrinaemia, since it could not be blocked by a simultaneous treatment with proglumide - a gastrin receptor blocker. It is concluded that the observed phenomenon is a direct result of a lower gastric acidity, as a consequence of omeprazole treatment.
Open Access
Ultrastructural localisation of acid phosphatase in intestinal eosinophilic granule cells (EGC) of rainbow trout
(Murcia : F. Hernández, 1992) Powell, Mark D.; Briand, Heather A.; Wright, Glenda M.; Burka, John F.
Enzyme cytochemistry was used to investigate possible lysosome involvement in capsaicin induced degranulation of the eosinophilic granule cell (EGC) of the rainbow trout intestine. Three adult rainbow trout (Oncorhynchus mykiss) were injected intra 'k eritoneally with capsaicin in a saline vehicle (0.5 pg.g- body weight). Following a 2 hour period of incubation, the fish were killed, and a mid portion of the intestine was dissected and fixed in cold glutaraldehyde buffered with sodium cacodylate. Vibratome sections were incubated in either reaction medium containing B-glycerophosphate and cerium chloride in acetate buffer or substrate (Bglycerophosphate) deficient control medium. Sections were then refixed in osmium tetroxide and processed for electron microscopy. Acid phosphatase was found to be localised within lysosomes. The enzyme was not found in the large cytoplasmic granules under normal or capsaicin-stimulated conditions. EGCs which had migrated to the lamina propria in response to the capsaicin stimulation had a distinct multivesicular granule morphology. These multivesicular granules did not contain acid phosphatase suggesting that this form of EGC degranulation is not a lysosomally mediated event.
Open Access
Early in-vitro histological chondral differentiation
(Murcia : F. Hernández, 1992) Gil, J.; Gimeno, M.; Murillo-Ferrol, Narciso; Bascuas, J.A.
In vitro chondrogenesis is possible in the chick embryo from stage 4 of Hamburger and Hamilton (1951), only 18-19 hours of incubation, before somite formation. In stage 4 of Hamburger and Hamilton (1951) the chondroblasts are placed laterally to the primitive streak and notochord cells are not necessary for cartilage differentiaton.
Open Access
Localization of blood coagulation factors in the germinal centers of human Peyer's patches
(Murcia : F. Hernández, 1992) Kudo, S.; Yamakawa, Mitsunori; Imai, Yutaka; Tsukamoto, M.
The immunohistochemical distribution of 15 blood coagulation factors in the germinal centers (GCs) of human Peyer's patches (PPs) was studied. Although factor VIII, active alpha-thrombin, and fibrinogen were hardly evident in the GCs, the majority of coagulation factors, such as kallikrein, high-molecular-weight kininogen, factos XII, X, IX, VII, V, XIIIa and XIIIb, prothrombin, anti-thrombin 111 and inactive alpha-thrombin were found, showing a lace-like staining pattern similar to that obtained with a monoclonal antibody, R4123, specific for follicular dendritic cells (FDCs) in the GCs. By immunoelectron microscopy, positive reactions for factor X and XIIIa were found on the surfaces of FDCs, GC cells, andlor in the intercellular spaces of GCs, being especially marked on the surface of the labyrinth-like structure of FDCs. It is concluded that a majority of coagulation factors are localized in the GCs of human PPs. Furthermore, it is suggested that some of these coagulation factors have a close topographical relationship with FDCs.
Open Access
Effect of cholesterol and its autooxidation derivatives on endocytosis and dipeptidyl peptidases of aortic endothelial cells
(Murcia : F. Hernández, 1992) Fornas, E.; Mayordomo, F.; Renau-Piqueras, J.; Alborch, E.
The effects of cholesterol (CHO) and cholesterol autooxidation derivatives (CAD) on the endocytosis of cationized ferritin (CF) by endothelial cells have been investigated. The effect of both substances on the activity of lysosomal enzymes dipeptidyl peptidase 1 (DPP 1) and dipeptidyl peptidase 11 (DPP 11) was also studied. Treatment of rats with CAD induced striking alterations in the ultrastructure of endothelial cells and makes it impossible to analyze the effect of this toxin on endocytosis processes. In contrast, CHO-treated cells displayed a good ultrastructural preservation and showed an increased ability to endocyte ferritin, as compared with controls. Both DPPI and DPP 11 activities increased after 3 weeks of CAD or CHO treatment. Our results indicate that although CHO damage endothelial cells, the most important effects could be attributed to CAD which usually accompanies CHO-supplemented diets.
Open Access
Intimal thickening in arterial autografts. Role of the adventitial layer
(Murcia : F. Hernández, 1992) Buján, J.; Bellón, J.M.; Gianonatti, M.C.; Golitsin, A.
In the present work, the repairing response of the iliac arterial wall is studied after carrying out autografts in segments of these vessels. The formation of the intimal hyperplasia, which occurred in al1 the cases, was followed at the biochemical leve1 (tritium thymidine incorporation) and with light and electron microscopy. The adventitial layer showed great activity during the repairing process. We believe that it plays an important role not only in neoadventitial formation, but also in myointimal raising.
Open Access
Changes in the ventral dermis and development of iridophores in the anadromous sea lamprey, Petromyzon marinus, during metamorphosis: an ultrastructural study
(Murcia : F. Hernández, 1992) Wright, Glenda M.; McBurney, Kim M.
The ultrastructural changes that take place in the ventral dermisalong with the development of iridophores were examined in the anadromous sea lamprey, Petromyzon marinus, during metamorphosis. There is a disruption of al1 components of the ventral dermis and a reformation that results in a sturcture very similar to that prior to metamorphosis. Although not a dermal component, a layer of iridophores develops directly beneath the dermis during late metamorphosis. The dermal endothelium is lost by mid metamorphosis (stage 4) and the highly organized collagenous lamellae making up the bulk of the dermis become disrupted by the migration of fibroblasts into the region. Many of these fibroblasts are involved in the degradation of the lamellae. By stage 5 of metamorphosis some fibroblasts become highly active collagen synthesizing cuboidal shaped cells that align to form a layer above the reformed dermal endothelium. New lamellae are formed by these cuboidal cells which then divide and migrate into the lamellae where they assume the characteristic attenuated appearance of fibroblasts in the adult dermal lamellae region. Iridophores first appear during stage 5 directly beneath the dermal endothelium. Reflecting platelets develop from double membraned vesicles associated with the Golgi apparatus. By late metamorphosis, stacks of trapezoidal shaped platelets fill the cytoplasm of the iridophores. The significance of the changes in the dermis during metamorphosis are discussed. This work is part of a continuing series of studies on the connective tissues in the anadromous sea lamprey.
Open Access
The ependymal surface of the fourth ventricle of the rat: a combined scanning and transmission electron microscopic study
(Murcia : F. Hernández, 1992) Alvarez-Morujo, A.J.; Toranzo, D.; Blazquez, J.L.; Pelaez, B.; Sánchez, A.; Pastor, F.E.; Amat, G.; Amat, P.
The morphological features of the ependymal surface and supraependymal elements of the fourth ventricle of the rat were examined by scanning electron microscopy (SEM) and by the transmission electron rnicroscopy (TEM). The results confirm the following aspects: 1) The presence of supraependymal elements and microvilli in the ependymal territories, including the sites where the cilia completely cover the ependymal surface; 2) The existence of cilia with oval or sphencal thickenings together with supraependymal bulbs similar in size to those of the larger ciliary swellings; 3) Identification of the long supraependymal fibres with intermittent fusiform dilations observed under the SEM with the neme fibres seen under the TEM; 4) The existence of intraventricular axodendritic synapses.
Open Access
Peritoneal fine structure of inguinal hernia: a transmission electron microscope study
(Murcia : F. Hernández, 1992) Baradi, A.F.; Parry, B.R.; Heslop, J.H.
Fine structure of normal human parietal peritoneum served as control data for recording changes in the fine structure of the peritoneum of hernial sacs. In these sacs, mesothelial cells retracted, rounded up and some of them eventually separated altogether to give rise to wide open intercellular spaces thus creating unhindered passageways (stomata) between the subserosal connective tissue and the cavity of the sacs. There was a considerable collagen build-up in the subserosal fibrous tissue of hernial sacs. Occurrence of this fibrosis is at variance with an accepted surgical concept which suggests a defect in collagen synthesis as the cause of herniation. In some sacs mesothelial nodules andior peritoneal adhesions were present. Certain cytological changes in the mesothelial cells of hernial sacs showed features in common with cells of malignant tumours in general, and features mimicing malignant mesotheliomas in particular. This is in spite of the fact that thorough gross and light microscopic examination of operative specimens and cytological evaluation of peritoneal effusion failed to reveal any evidence of malignancy. Pathologists should be aware of the consummate ability of mesothelial cells to mimic carcinomas in order to avoid possible diagnostic errors. In this report, an electron micrograph of peritoneal adhesion is being published for the first time in the literature. A syncytium-like firm bond between adjoining mesothelial cells constituted the adhesion which is obviously an irreversible process.
Open Access
Effects of captopril on the development of rat doxorubicin nephropathy
(Murcia : F. Hernández, 1992) Squadrito, F.; Macchiarelli, C.; Santoro, G.; Arcoraci, V.; Trimarchi, G.R.; Sturniolo, R.; Nottola, S.A.; Motta, P.M.; Caputi, A.P.
The effects of a daily administration of an anti-converting enzyme inhibitor, Captopril (CPT) (100 mg/kg/orally), on the development of functional and morphological alterations induced in rats by a single injection (7.5 mg/kg/iv) of Doxorubicin (DXR) (Adnamycin*), were investigated. Twenty-four-hour protein excretion, urine output, food intake, water intake, and body weight gain were measured weekly for 30 days. Transmission and scanning electron microscopy observations were performed on kidney samples after 30 days. Four groups were studied. Group 1 were control rats. Group 2 were rats injected with DXR. Group 3 were rats injected with DXR and treated with CPT for 30 days. Group 4 were rats injected with DXR and treated with CPT for 15 days (CPT treatment started 15 days after DXR injection). Group 1 did not show significant functional or morphological changes. Group 2 showed severe proteinuria, significant increase in urinary volume within 2 weeks, significant body weight reduction and diffuse morphological changes. These changes mainly consisted of podocyte swelling, severe foot process fusion, and presence of casts within tubular lumen. Group 3, with respect to group 2, showed a significant reduction of the 24 h protein excretion and urine output. This group displayed morphological changes similar to those observed in group 2, but with a focal distribution. Group 4 showed functional and morphological changes comparable with those of group 2. It is concluded that CPT partially inhibits the development of the functional and morphological damage induced by DXR in the rat kidney. However, CPT did not influence the natural development of nephropathy when treatment started 15 days after DXR injection.
Open Access
Neurotrophic factor-like effect of FPF1070 on septal cholinergic neurons after transections of fimbria-fornix in the rat brain
(Murcia : F. Hernández, 1992) Akai, F.; Hiruma, S.; Sato, T.; Iwamoto, N.; Fujimoto, M.; Ioku, M.; Hashimoto, S.
FPF1070 is an aqueous protein-free solution, which consists of 85% free amino acids and 15% small peptides. Our previous study showed a potent neurotrophic factor-like activity in cultured embryonic cells of dorsal root ganglia. The present study investigated whether FPF1070 regenerated the cholinergic cells in the media1 septal nucleus after axonal transections by cutting the fimbria-fornix. Fimbrial transections reduced the number of septal cholinergic cells by 30 + 3.6%, compared with the number on contralateral sides at 4 weeks. Intrapretioneal injections of FPF1070 caused 49.9 * 6.3% of the cholinergic neurons to survive. Furthermore, the cell sizes of the cholinergic neurons were significantly different: 16.4 + 4.2 pm, 14.3 I3. 8 pm in FPF1070 treatment and vehicle treatment, respectively. These results indicated that FPF1070 prevents the degeneration and atrophy of impaired cholinergic neurons by systemic administration.
Open Access
Morphology and functional responses of isolated inner adrenocortical cells of rats infuse with interleukin-B
(Murcia : F. Hernández, 1992) Rebuffat, P.; Malendowicz, L.K.; Andreis, P.G.; Meneghelli, V.; Kasprzak, A.; Nussdorfer, G.G.
The effects of the prolon Ye d infusion with interleukin-1B (IL-10) (20 pM.kg- .min- ') on the function and morphology of the isolated inner cells of the rat adrenal cortex were investigated. After 3 and 5 days of IL-1B infusion, the level of circulating ACTH was below the control level, while the plasma concentration of corticosterone was strikingly elevated. After 5 days of infusion, isolated inner adrenocortical cells showed an enhanced basal and ACTH-stimulated corticosterone secretion, and showed a conspicuous hypertrophy. The acute exposure to IL-1B 10" M did not affect the secretory activity of dispersed cell from either control or IL-lB-infused rats. These findings indicate that the prolonged exposure to high levels of circulating IL-lB, like those occurring during chronic inflammatory diseases, is able to enhance the growth and steroidogenic (glucocorticoid) capacity of the rat inner adrenocortical zones. Moreover, they suggest that the mechanism underlying this adrenocorticotrophic effect of IL-1B does not involve either a stimulation of the hypophyseal ACTH release or a direct stimulatory effect of monokine on adrenocortical cells. It is suggested that IL-1B may activate an intra-adrenal paracrine regulatory mechanism.
Open Access
Etiology of the developing eye in myelencephalic blebs (my) mice
(Murcia : F. Hernández, 1992) Center, Elizabeth M.; Polizotto, René S.
The etiology of the eye defects in myelencephalic blebs (my) mutant mice has been poorly understood for almost seventy years. Embryos from 9 to 14 M days of gestation were subjected to Alcian blue 8GX staining for acidic glycosaminoglycan deposition in basement membrane structures of the developing eye in my stock and control specimens. In addition 12 day embryos were subjected to avidinbiotin- peroxidase labelling for laminin. At 9 - 9 M days of gestation more Alcian blue positive extracellular matrix was found in the region between the optic vesicle and the overlying putative lens ectoderm in the my stock embryos. By 12 days, there was an irregular and lesser amount of deposition of glycosaminoglycans in the len's capsule and in the «inner lirniting membrane~ of the presumptive neural retina; however, the deposition of laminin appeared to be greater in the inner lirniting membrane of the my eye. By 14 days, the damage to the eye in the my embryos can be quite extensive, and the deposition of glycosaminoglycans was very meager in this situation. It appears that irregular deposition of glycosaminoglycans in the extracellular matrix and possible increase in the amount of laminin in basement structures in my embryos indicate disruption of the normal histochemistry involved in the development of the eye. Altered histochemistry may in turn indicate changes in permeability between cells of the developing tissues which result in the blebbing.
Open Access
Differential proliferation of rat aortic and mesenteric smooth muscle cells in culture
(Murcia : F. Hernández, 1992) Waldbillig, David K.; Pang, Stephen C.
Smooth muscle cells (SMC) from various arterial origins have been successfully maintained in culture. The present study evaluates the proliferative activity of aortic and mesenteric SMC in culture. Aortic and mesenteric SMC were obtained from male Wistar rats by explant and enzyme digestion techniques, respectively. Vascular SMC obtained by either method exhibited a characteristic hill-and-valley growth pattern in culture after confluence and were positively labelled with either anti-smooth muscle actin or myosin by an indirect immunofluorescent method. The rate of incorporation of thymidine into DNA and cell number counting were used as indices of proliferation in vitro. Vascular SMC from passages 4-33 were first synchronized with either Dullbecco's Modified Eagle's Medium (DME) or Ham's F-12 medium, supplemented with insulin-transfemngselenium (ITS), for 72 hours. SMC were then stimulated with 10% bovine serum for either 24 or 72 hours with the former processed for scintillation counting, the latter for cell number determination. The incorporation of tritiated thymidine into DNA following a 2 hour incubation was determined by scintillation counting after perchloric acid extraction. In terms of cell numbers, proliferative responses to bovine serum were determined by Coulter counting. Autoradiography was also carried out in some cultures to determine both thymidine and mitotic labelling indices. The rate of thymidine incorporation in aortic cells was 2-3 fold higher than in mesenteric cells. Aortic and mesenteric SMC lines exhibited similar cell cycle intervals in terms of total duration and individuals cycle parameters. However, the total thymidine index was higher in the aortic than mesenteric SMC. These results suggest that SMC from different arterial origins possess different rates of proliferation. Differences in the rate of in vitro proliferation in these cell lines are due to differences in growth fraction, the number of celis traversing the cell cycle. The mechanisms underlying these differential proliferative potentials remain to be determined.
Open Access
Hypophyseal pathology in AIDS
(Murcia : F. Hernández, 1992) Mosca, L.; Costanzi, G.; Antonacci, C.; Boldorini, R.; Carboni, N.; Cristina, S.; Liberani, C.; parravicini, C.; Pirolo, A.; Vago, L.
One hundred and eleven pituitary glands of patients (93 males, 18 females; mean age 32 years, 5 months) who died of fully developed AIDS or ARC were examined under light microscopy with the aid of immunohistochemistry. On post mortem (p.m.) examination a wide series of multiorgan alterations was noticed. Microscopically vanous lesions in both adeno- and neurohypophysis were seen. These ranged from vessel damage to secondaries to systemic infections, neoplasms and functional derangements. Necrotic lumps due to recent infarction could appear in both parts of the gland, while old fibrous scars sustained a previously overcome necrosis. Different pathogens (mainly fungi) could be seen either within the gland or arising from its meningeal surroundings. Examples of tumour pathology were provided by microadenomas, gliosis/gliomas; the frequency of adenomas (11.7%) was similar to that typical of senility. The functional impairment was mainly connected with ACTH cell hyperplasia, which seems in keeping with corticoadrenal or ACTH-receptor damage.

Browse

Browsing Histology and histopathology Vol. 7, nº 2 (1992) by Issue Date

Results Per Page

Sort Options