Apical cytoplasm

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

Morphological and histochemical study of the endometrial effects of Ovral in the baboon

Abstract: In an effort to better understand changes induced by hormonal contraceptives, a group of female baboons were administered Ovral for a period of 9 months. During this time the endometrium was sampled by transcervical uterine biopsy from both the treated animals and from a control group. The biopsies were all obtained between 10 and 14 days of the treatment cycle or the normal menstrual cycle. The endometrial glandular cells from the treated animals exhibited an accelerated maturation compared with the controls. Ultrastructurally this was reflected by increased cell size, numerous long, slender microvilli on the apical membranes, and increased development of the Golgi complex. Differences were also observed in the predominant type of granule seen in the apical cytoplasm. After 3 and 6 months of treatment with Ovral, no significant differences were noted between groups or between animals within a group. However, after 9 months of treatment, the endometrium displayed differences from the earlier experimental groups as well as individual variations. The functional correlates of these observations are discussed and compared to human endometrium.

Cytochemical variations of human von Ebner's glands.

Abstract: Human von Ebner's glands were analyzed during fetal and childhood development, and adultness, with the purpose of observing possible age-related cytochemical changes. Tongues from 8-38 weeks-old fetuses, samples of the lingual V from newborns, 8 to 14 years-old children and adults aged 20 years and older were used. H/E, and techniques for mucosubstances (PAS, PAS/amylase, PAS/sialidase, methenamine-silver, Alcian blue at pH 2.5 and 1.0, and Toluidine blue at pH 3.8) were employed. Between 16 and 20 weeks acini and ducts in the process of formation were identified, being the parenchyma completely developed at 24 weeks. The morphology of glands from newborns consisted of basophilic and periodate-negative serous acini. In infants secretory cells contained PAS positive apical granules that were sensitive to sialidase, periodate-reactive and slightly metachromatic. These characteristics were increased with age. Besides, in adults, the apical cytoplasm of the adenomerous and the luminal content were also alcianophilic. The cytochemical variations observed indicates that human von. Ebner's glands are composed of cells of the seromucous type that contain sialomucins and sulphomucins.

Ejaculatory duct of the migratory grasshopper, Melanoplus sanguinipes (fabr.) (Orthoptera : Acrididae): A histological and ultrastructural analysis

Abstract: The ejaculatory duct of the migratory grasshopper ( Melanoplus sanguinipes [Fabr.]) (Orthoptera : Acrididae) is divisible into 3 regions: upper ejaculatory duct (UED) into whose anterior end the accessory glands and vasa deferentia empty; the funnel characterized by its slit-like lumen; and the lower ejaculatory duct (LED). Anteriorly, the UED has a keyhole-shaped lumen surrounded by a thin intima and highly columnar epithelial cells whose most conspicuous feature is massive aggregations of microtubules. More posteriorly, the UED lumen differentiates into dorsal and ventral chambers, the former having a thick cuticular lining armed with spines. In the hindmost part of the UED, the ventral chamber expands to obliterate the dorsal chamber; its cuticular lining thickens, and conspicuous lateral evaginations develop. The thick cuticle includes 3 distinct layers and on its surface carries numerous spatulate processes. In this region, the epithelial cells develop numerous short microvilli beneath which are many mitochondria. As the funnel is reached, the intima becomes extremely thick, and the epithelial cells lack microvilli and most microtubules. Within the funnel, a new, very distinct form of cuticle appears, which is in “units”, each associated with an epithelial cell and having a rounded epicuticular cap. The new cuticle arises ventrally but rapidly spreads to encircle the entire lumen, at which point the LED is considered to begin. Beneath this new cuticle, the epithelial cells are columnar, have long microvilli, numerous mitochondria in the apical cytoplasm, and rough endoplasmic reticulum basally. Apically, adjacent cells are tightly apposed; however, prominent intercellular channels develop more basally. The ejaculatory duct's features are briefly discussed in terms of its role in spermatophore formation.

BBS4 protein has basal body/ciliary localization in sensory organs but extra-ciliary localization in oligodendrocytes during human development

Abstract: Bardet-Biedl syndrome protein 4 (BBS4) localization has been studied in human embryos/fetuses from Carnegie stage 15 to 37 gestational weeks in neurosensory organs and brain, underlying the major clinical signs of BBS. We observed a correlation between the differentiation of the neurosensory cells (hair cells, photoreceptors, olfactory neurons) and the presence of a punctate BBS4 immunostaining in their apical cytoplasm. In the brain, BBS4 was localized in oligodendrocytes and myelinated tracts. In individual myelinated fibers, BBS4 immunolabelling was discontinuous, predominantly at the periphery of the myelin sheath. BBS4 immunolabelling was confirmed in postnatal developing white matter tracts in mouse as well as in mouse oligodendrocytes cultures. In neuroblasts/neurons, BBS4 was only present in reelin-expressing Cajal-Retzius cells. Our results show that BBS4, a protein of the BBSome, has both basal body/ciliary localization in neurosensory organs but extra-ciliary localization in oligodendrocytes. The presence of BBS4 in developing oligodendrocytes and myelin described in the present paper might attribute a new role to this protein, requiring further investigation in the field of myelin formation.

Estrutura microscópica do complexo tubular: rede testicular e ductos excretores proximais do testículo em codorna doméstica (Coturnix coturnix)

Abstract: Rete testis (RT) of quail was formed by epithelial passageways localized initially into the albuginea layer that recover the cranial pole of the testis passing afterwards to the related proximal epididymal region (ER). At the ER occurred a continuance of RT passageways with the mainly shaped chambers of the proximal efferent ducts (PED). PED had continuance with the distal efferent ducts (DED), forming an anastomotic tubular complex of RT–efferent ducts inside the ER. Small differences were noted on the RT-DEP-DED histologic structure along the year, being more evident in spring and autumn, respectively the active and quiescent phases of the annual testis cycle. More expressive variability was noted between the principal (P) epithelium cells and in tubular diameters of DEP-DED, during the two focused seasons. Spring features of RT-DEP-DED were characterised by relative enlargement of the passageways and marked organelle development in the apical cytoplasm of P cells, allowing conclude presence of active processes of endocytoses. Fall quiescence was marked by an enfolding pattern of all the tubular passageways, lacking of spermatozoa and small amount of heterogeneous material inside their luminal compartments, followed by presence of ultrastructural degenerative features in apical cytoplasm of P cells and ciliated cells of the DEPDED complex.