Apical cytoplasm

About: Apical cytoplasm is a research topic. Over the lifetime, 1080 publications have been published within this topic receiving 36131 citations.

The ampulla of the vas deferens in goats

Abstract: Zusammenfassung Zentrales Lumen und tubulo-alveolare Drusen der Samenleiterampulle der Ziege sind mit einem stellenweise einschichtig zylindrischen, stellenweise zweireihig zylindrischen Epithel ausgekleidet. Man kann Zylinderzellen und Basalzellen unterscheiden. Beide Zellarten enthalten reichlich Glykogen. Lipid-partikel lassen sich nicht nur in den Basalzellen, sondern in feinerer Verteilung auch in den Zylinderzellen nachweisen. Im elektronenmikroskopischen Bild fallen die Zellkerne der Basal- und Zylinderzellen durch das Vorkommen tiefer Cytoplasmainvaginationen auf, die den Kernen manchmal ein fragmentiertes Aussehen geben. Das granulare endoplasmatische Retikulum der Zylinderzellen bildet unregelmasig begrenzte Verdichtungszonen (Plaques) aus, die mit einer lockereren Ergastoplasmatextur in ihrer Umgebung kontrastieren. Mikrovillifreie apikale Cytoplasmaprojektionen einzelner Zylinderzellen werden im Zuge eines apokrinen Extrusionsprozesses vom basalen Cytoplasma demarkiert und abgenabelt. Im supranuklearen Cytoplasma der Zylinderzellen massieren sich viele dense bodies, wahrscheinlich lysosomaler Natur. Die starke, histochemisch nachweisbare Aktivitat von Glycerinaldehyd-phosphatdehydrogenase und Lactatdehydrogenase sowie die verhaltnismasig geringen Mengen von Isocitratdehydrogenase, Succinatdehydrogenase und Malatdehydrogenase lassen vermuten, das der Glykosekette eine besondere Bedeutung fur die Energieversorgung des Samenleiterampullenepithels zukommt. Die kraftige Reaktion des Epithels auf Glucose-6-phosphatdehy-drogenase wird im Zusammenhang mit der Fruktosebildung in der Samenleiterampulle diskutiert. Summary The ampulla of the vas deferens of the goat The central lumen and the tubular alveolar glands of the ampulla of the vas deferens of the goat are lined by cylindrical epithelium which is single-layered in parts and double-layered in others. It is possible to distinguish cylinder cells and basal cells. Both types of cell are rich in glycogen. Lipid particles are found not only in the basal cells but are also finely distributed in the cylinder cells. Under the electron-microscope the nuclei of the basal and cylinder cells show deep cytoplasmic invaginations which often give the nucleus a fragmented appearanec. The granular endoplasmic reticulum of the cylinder cells forms irregularly bounded zones of thickening (plaques) which are in marked contrast to the looser ergastoplasmic texture around them. Apical cytoplasm projections of individual cylinder cells free from microvilli are demarcated and separated from the basal cytoplasm by means of an apocrine extrusion process. In the supranuclear cytoplasm of the cylinder cells there accumulate many dense bodies which are probably lysosomal in nature. The marked histochemically demonstrable activity of glycerinaldehyde phosphate-dehydrogenase and lactate-dehydrogenase, together with the relatively small quantities of isocitrate-dehydrogenase, succinate-dehydrogenase and malate-dehydrogenase, suggest that the glucose chain is of particular significance for the provision of energy for the epithelium of the ampulla of the vas deferens. The marked reaction of the epithelium to glucose-6-phosphate dehydrogenase is discussed in relation to the formation of fructose in the ampulla. Resume Sur l'ampoule du canal deferent de la chevre La lumiere centrale et les glandes tubulo-alveolaires de l'ampoule de la chevre sont revetues d'un epithelium cylindrique en partie monostratifie et en partie bistratifie. On peut distinguer les cellules cylindriques des cellules basales. Les deux especes cellulaires sont richement pourvues en glycogene. On peut mettre en evidence des particules lipidiques, non seulement dans les cellules basales, mais aussi, en tres fine repartition, dans les cellules cylindriques. Au microscope electronique, on observe de profondes invaginations cytoplasmiques dans les noyaux des cellules basales et cylindriques, qui donnent parfois a ces noyaux un aspect fragmente. Le reticulum endoplasmique granuleux des cellules cylindriques forme des zones plus denses, limitees irregulierement (plaques), qui contrastent avec la texture ergastoplasmique plus lâche de leur entourage. Des projections cytoplasmiques apicales, exemptes de microvillosites, de quelques cellules cylindrique sont demarquees et se separent du cytoplasme basal au cours d'un processus d'extrusion apocrine. Dans le cytoplasme supranucleaire des cellules cylindriques s'amassent de nombreuses inclusions denses, probablement de nature lysosomique. L'intense activite des dehydrogenases glycerine-aldehyde-phosphorique et des dehydrogenases lactiques, que l'on peut mettre en evidence histochimiquement, de meme que les quantites relativement faibles de dehydrogenaes isocitriques, succiniques et maliques nous laissent supposer que le cycle du glucose joue un role particulier dans le metabolisme energetique de l'epithelium de l'ampoule. On discute la forte reaction de l'epithelium aux dehydrogenases glucose-6-phosphoriques, en relation avec la formation du fructose dans l'ampoule. Resumen Sobre la ampolla del conducto deferente del macho cabrio La luz central y las glandulas tubulo-alveolares de la ampolla del conducto deferente se hallan revestidas por un epitelio cilindrico, a trechos mono-estratificado, a trechos de dos filas. Pueden distinguirse celulas cilindricas y celulas basales. Ambos tipos celulares contienen glucogeno en abundancia. Particulas lipidas no solo se pueden identificar en las celulas basales, sino en distribucion mas fina tambien en las celulas cilindricas. En la imagen elec-tronicomicroscopica sorprenden los nucleos celulares de las celulas basales y cilindricas por la presencia de invaginaciones citoplasmaticas profundas, que le deparan a los nucleos, en ocasiones, un aspecto fragmentado. El reticulo endoplasmatico granular de las celulas cilindricas forma zonas de condensacion (placas) delimitadas con irregularidad, que contrastan con la textura ergoplasmatica mas laxa a su alrededor. Proyecciones citoplasmaticas apicales, libres de microvellosidades, de las distintas celulas cilindricas se demarcan y estrangulan a lo largo de un proceso extrusivo apocrino. En el citoplasma supranuclear de las celulas cilindricas se amontonan muchos corpusculos densos, tal vez de naturaleza lisosomica. La actividad considerable de glicerinalde-hidofosfatodehidrogenasa y lactatodehidrogenasa, identificables histoquimicamente, asi como las cantidades relativamente escasas de isocitratodehidrogenasa, permiten sospechar que a la cadena de glucosa le corresponde un significado especial para el abastecimiento energetico del epitelio de la ampolla del conducto deferente. La reaccion potente del epitelio frente a la glucosa-6-fosfatodehidrogenasa se discute en relacion con la formacion de fructosa en la ampolla del conducto deferente.

[The fine structure of the gustatory cells of the circumvallate, foliate and fungiform papillae in hibernating bats].

Abstract: The cells of vallate, foliate and fungiform papillae were studied in insectivore hibernating bats (Pipistrellus pipistrellus and Rhinolophus ferrumequinum) in the various epochs of the year in order to show cell types the seasonal changes. On the basis of the ultrastructural aspects and the relationships with nerve endings, besides the few basal cells, three types of sensorial cells can be identified: dark type I cells, light type II cells and light type III cells. All gustatory cells, long and narrow shaped, extend from the epithelial basal lamina to the gustatory canal, where they send long microvillous expansions of the apical cytoplasm. These expansions, except those of the fungiform papillae which never extend beyond the lower two thirds, usually reach the external opening of the taste pore, always completely void of dense substance. Dark type I cells are characterized by a developed RER and large granules. Light type III cells show peculiar dense core light vesicles, labelled protein A-gold particles immunoreactive to 5-HT. These cells only in the foliate and fungiform papillae also have bundles of microtubules whose function is still unknown. After comparative evaluation and discussion of topographical and ultrastructural aspects with those of other mammals and humans, the Authors states that bats are provided with a valid gustatory system and that all cell types are involved in taste transduction.

Immuno-histochemical and -cytochemical evidence suggesting the presence of Campylobacter jejuni and Campylobacter coli in cases of porcine intestinal adenomatosis.

Abstract: Antisera against a number of Campylobacter species were used in immuno-histochemical and -cytochemical studies on cases of porcine intestinal adenomatosis. Avidin-biotin-complex (ABC) and streptavidin immunoperoxidase methods were used on formalin-fixed, paraffin-embedded and frozen sections. Protein A gold method was used on formaldehyde fixed and frozen sections for immuno-cytochemistry. The antisera used were raised in rabbits by subcutaneous or intravenous injection of living or formalin treated organisms. Antisera against different serotypes of the thermotolerant, catalase positive Campylobacters, Campylobacter jejuni and Campylobacter coli gave positive reactions in the immuno-histochemical studies. The staining was found in intestinal epithelial cells both in the ileum and in the colon and was restricted to the apical cytoplasm of adenomatous epithelial cells. The staining had a granular pattern, the positive structures sometimes having the shape of Campylobacter. Epithelial cells in areas with normal differentiation of goblet cells did not stain. In contrast, no staining resulted with antisera against Campylobacter sputorum subsp. mucosalis and Campylobacter hyointestinalis. Immuno-cytochemistry, using antisera against Campylobacter jejuni showed that the positive staining in altered epithelial cells were restricted to intracellular organisms having a structure resembling Campylobacter spp.

An Episode of Proliferative Hemorrhagic Enteropathy Associated with Lawsonia Intracellularis in a Pig Farm from Romania

Abstract: Introduction: In swine, Lawsonia intracellularis is known to be responsible for porcine proliferative enteropathy. The syndrome can be divided in an acute intestinal hemorrhage (proliferative hemorrhagic enteropathy) affecting naive adult pigs and a wasting disease (porcine intestinal adenomatosis) in growing pigs. As new diagnostic techniques develop, there is increased number of pig farms where L. intracellularis is being identified worldwide. Aims: There are few reports of L. intracellularis outbreaks in Romania. We aimed to describe the clinical signs, treatment, outcome, gross necropsy and histopathological lesions from an episode of proliferative hemorrhagic enteropathy associated with L. intracellularis in a farm from Transylvania. Materials and methods: A farm of 4000 pigs (TOPIGS line) from Bistrita-Nasaud County. The microscopical examination was composed of Hematoxilin and Eosin exam, Warthin-Starry silver stain and immunohistochemistry for Multi-Cytokeratin. Results: Over a period of 6 days, a total number of 10 pigs dyed (from 2000 animals in the age group 90-120 days), and 1 pig dyed (from 1000 animals in the age group 60-90 days) with pallor, anorexia or with no clinical signs. Gross lesions were represented by pallor of the carcass and were restricted to the ileum. The intestinal wall was thicker (cerebriform aspect) and turgid. A mixture of blood and fibrin was present in the ileum, impregnating the faeces in the large intestine. Histologically the mucosa was thicker due to epithelial proliferation (Multi-Cytokeratin positive), with few Goblet cells, with severe erosion, necrosis and haemorrhage. Curved rod-shaped bacteria with morphology consistent with L. intracellularis were observed in the apical cytoplasm of epithelial cells using the Warthin-Starry silver stain. The food was medicated with chlortetracycline (20 - 40 mg a.s./kg b.w./day) and the pigs remained healthy, with no further mortality. Conclusion: We report here an outbreak of proliferative hemorrhagic enteropathy associated with L. intracellularis in a pig farm from Romania, emphasizing the importance of early diagnostic and control measures for this disease.

Structural and biochemical modifications in parotid gland induced by fasting.

Abstract: Structural, ultrastructural and biochemical modifications produced by fasting in the parotid gland of guinea pig, were studied. The highest storage of secretory granules was found in the apical cytoplasm after a 12 hour fasting period. The curve of soluble proteins showed that the highest storage of proteins in the parenchyma took place after a 10/12 hour fasting period. Amylase activity reached its highest point after a 10 hour fasting period. We suggest that granules stored in cellular cytoplasm after a 12 hour fasting period would have completed their maturation cycle.