Showing papers on "Apical cytoplasm published in 1991"

Expression of Tn and sialyl-Tn antigens in tumor tissues of the ovary.

Abstract: The expression of sialyl-Tn and Tn antigens in various benign, borderline, and malignant ovarian tumors was examined immunohistochemically using newly developed antibodies specific for sialyl-Tn and Tn antigens. Sialyl-Tn antigen was detected in only one benign tumor, a mucinous adenoma that showed faint cytoplasmic staining in a few cells. However, sialyl-Tn was present in 5 of 12 serous borderline tumors, 10 of 19 mucinous borderline tumors, 10 of 13 serous adenocarcinomas, 15 of 16 mucinous adenocarcinomas, 14 of 15 endometrioid adenocarcinomas, and 7 of 7 clear cell carcinomas of the ovary. The antigen expression was observed throughout the cytoplasm of cancer cells and in the apical cytoplasm and luminal contents of some glands. The incidence and intensity of staining for sialyl-Tn antigen were higher in malignant tumors than in borderline tumors, but these results did not correlate with the histologic classification or differentiation. Coexpression of sialyl-Tn antigen and Tn antigen was observed in two serous adenocarcinomas, six mucinous borderline tumors, five mucinous adenocarcinomas, eight endometrioid, and seven clear cell carcinomas. In no case was Tn antigen expressed without concomitant sialyl-Tn antigen expression. Accumulation of sialyl-Tn antigen seems to be an early event of carcinogenesis of the ovary.

The follicular placenta of the viviparous fish, Heterandria formosa. I. Ultrastructure and development of the embryonic absorptive surface.

Abstract: Embryos of the poeciliid Heterandria formosa develop to term in the ovarian follicle in which they establish a placental association with the follicle wall (follicular placenta) and undergo a 3,900% increase in embryonic dry weight. This study does not confirm the belief that the embryonic component of the follicular placenta is formed only by the surfaces of the pericardial and yolk sacs; early in development the entire embryonic surface functions in absorption. The pericardial sac expands to form a hood-like structure that covers the head of the embryo and together with the yolk sac is extensively vascularized by a portal plexus derived from the vitelline circulation. The hood-like pericardial sac is considered to be a pericardial amnion-serosa. Scanning and transmission electron microscopy reveal that during the early and middle phases of development (Tavolga's stages 10-18 for Xiphophorus maculatus) the entire embryo is covered by a bilaminar epithelium whose apical surface is characterized by numerous, elongate microvilli and coated pits and vesicles. Electron-lucent vesicles in the apical cytoplasm appear to be endosomes while a heterogeneous group of dense-staining vesicles display many features characteristic of lysosomes. As in the larvae of other teleosts, cells resembling chloride cells are also present in the surface epithelium. Endothelial cells of the portal plexus lie directly beneath the surface epithelium of the pericardial and yolk sacs and possess numerous transcytotic vesicles. The microvillous surface epithelium becomes restricted to the pericardial and yolk sacs late in development when elsewhere on the embryo the non-absorptive epidermis differentiates. We postulate that before the definitive epidermis differentiates, the entire embryonic surface constitutes the embryonic component of the follicular placenta. The absorptive surface epithelium appears to be the principle embryonic adaptation for maternal-embryonic nutrient uptake in H. formosa, suggesting that a change in the normal differentiation of the surface epithelium was of primary importance to the acquisition of matrotrophy in this species. In other species of viviparous poeciliid fishes in which there is little or no transfer of maternal nutrients, the embryonic surface epithelium is of the non-absorptive type.

Characterization of early kidney lesions in estrogen-induced tumors in the Syrian hamster.

Abstract: Syrian hamsters were treated with diethylstilbestrol (DES), a potent estrogen and kidney carcinogen, or ethinyl estradiol (EE), a strong estrogen but weak carcinogen, for 1–9 months. At monthly intervals their kidneys were studied using light, immunoperoxidase, and electron microscopic techniques. At 5 months, DES-treated animals exhibited interstitial lesions composed of small round cells with a high nuclear:cytoplasmic ratio. Immunoperoxidase and ultrastructural studies showed these cells to be similar to cells in fully formed tumors at 9 months. Early lesions in EE-treated animals (seen as early as 1 month) were dissimilar; these lesions appeared in the deep cortex adjacent to the renal pelvis, where proximal tubules underwent hyperplastic changes, showing columnar cells with large nuclei, occasional mitoses, and sloughing of apical cytoplasm. Cells in early lesions of EE-treated animals did not resemble the fully developed tumor in either immunoperoxidase or ultrastructural features; although with longer treatment these tubular lesions progressed to dysplasia (3–5 months) and severe dysplasia/carcinoma in situ (7 months), they did not form grossly visible tumors during the 9-month study. Both early lesions identified were specific, inasmuch as they were not observed in control animals and animals treated with β-dienestrol and 17α-estradiol (noncarcinogenic weak estrogens). Animals given a combination of DES and EE showed tubular hyperplasia but not interstitial lesions; this finding was of particular interest because hamsters given this combination of estrogens do not develop gross renal tumors. These results strongly implicate the primitive interstitial cell in the hamster kidney as the cell of origin of the DES-induced neoplasm.

Ultrastructure of palatal taste buds in the perihatching chick.

Abstract: Palatal taste buds of perihatching chicks were examined by electron microscopy. Four intragemmal cell types were characterized. (1) Light: with voluminous, electron-lucent cytoplasm containing scattered free ribosomes, rough and smooth endoplasmic reticulum, plump mitochondria, sparse perinuclear filaments, occasional Golgi bodies, and numerous clear and dense-cored vesicles. Clear vesicles sometimes aggregate in a presynaptic-like configuration apposed to an axonal profile. These cells contained large, spherical, uniformly granular nuclei with one nucleolus. (2) Dark: with dense cytoplasm containing filamentous bundles surrounding the nucleus, occasional clear vesicles, centrioles, rough endoplasmic reticulum, and compact mitochrondria. The apical cytoplasm noticeably lacks dense secretory granules. Irregular to lobulated nuclei are densely granular, and contain scattered clumps of chromatin, adhering especially to the inner leaflet of the nuclear membrane, and at least one nucleolus. Cytoplasmic extensions of dark cells envelop other intragemmal cell types and nerve fibers. Light and dark cells project microvilli into the taste pore. (3) Intermediate: contain gradations of features of light and dark cells. (4) Basal: darker than the other intragemmal cell types and confined to the ventral bud region. Putative afferent synapses in relation to light cells, and axo-axonal contacts are described. While the appearance of axo-axonal contacts may be a transient developmental event, other bud features are consonant with observations in adult chickens and suggest that the peripheral gustatory apparatus is mature at hatching in this precocial avian species.

F-actin localization during trochoblast differentiation embryos

Abstract: We have studied the development of the ciliated, Patella vulgata trochophore larvae. This organ, the different clones of trochoblasts. In each of these filamentous (F-) actin is formed at the time that which we visualized with TRITC-phalloidin, is cilia that crosses each trochoblast. Isolated quartets of animal micromeres (from which the form rows of cilia and F-actin bands at the proper embryos, the trochoblasts shift their position form a ring of differentiated prototroch cells with a encircling the entire larva. At the dorsal side, a and thus a double band of F-actin is present. In double F-actin band are found in trochophores in which dorsoventral axis is inhibited experimentally. shows that the F-actin band extends from the apical cytoplasm of the prototroch cells. At the rootlet connected to the basal body of each cilium can the cytoplasm toward the nucleus, and a band of actin- interconnect neighboring basal apparatus. Treatment of cytochalasin B disrupts the organization of the F- TRITC-phalloidin, affects the angle of the effective reduces their swimming capacity. This suggests that for the normal locomotory behavior of the Patella

Trans-epidermal Transport and Storage of Calcium in Holthuisana transversa (Brachyura; Sundathelphusidae) During Premoult

Abstract: Holthuisana transversa reabsorbs much of its exoskeletal calcium in the last 3 days before ecdysis and stores it in circulating granules in the haemocoel and in non-circulating granules in the subepidermal connective tissue. Calcium enters the epidermal cells from the moulting fluid, probably through their apical microvilli and is either incorporated into intracellular calcium granules or exits the cell via the basolateral membranes to be used in formation of two other granule types. Intracellular granules (0.4–2 μm long) form in large masses in the apical cytoplasm of the epidermal cells. They are formed as membrane-bound vesicles by the Golgi, and calcium and organic matrix material are added from the surrounding cytoplasm. As development proceeds, lamellae appear and calcium carbonate is deposited in the matrix. Granule masses move basally and are stored in the connective tissue. Calcium is also incorporated into extracellular large granules (0.8–3.8 μm long) which are formed in narrow intercellular channels between epidermal cells. A third granule type (small granules, 0.26 μm diameter) is formed in subepidermal connective tissue cells and released into the haemolymph in very large numbers. Calcium was identified in the two larger granule types using X-ray microanalysis and significant amounts of phosphorus and potassium were also present in the large granules. A model for ion cycling between the exoskeleton and granules is presented.

Choanocyte‐like cells in the digestive system of the starfish Marthasterias glacialis (Echinodermata)

Abstract: Two types of choanocyte-like cells have been found in the digestive tract of the starfish. Type I choanocytes are in the lining epithelium of all organs of the digestive system. These are narrow, columnar cells strongly anchored basally and expanded apically into a protuberance projecting into the lumen. A prominent flagellum surrounded by microvilli projects from the center of this protuberance. Apical cytoplasm contains numerous mitochondria, secondary lysosomes, and multivesicular bodies. A distinctive characteristic of these cells is a filament bundle that traverses the length of the cell from its region of attachment on the rootlet of the flagellar basal body to its terminus on the basal plasma membrane. Between the attenuated basal ends of type I cells are the nerve fibers of an intraepithelial nerve plexus. Thickness of the plexus is correlated with the quantity of type I cells in the epithelium. Type II choanocytes are in the cuboidal coelomic epithelium that forms the outer layer of digestive tract organs. These cells are smaller than those of type I, and they have an apical collar surmounted by a ring of 13 microvilli. Within the collar is a cup-shaped depression with a central flagellum. Coated vesicles, secondary lysosomes, and phagocytic infoldings are observed in and near the collar cytoplasm. Filament bundles similar to those in type I choanocytes are also observed in coelomic epithelial cells that are sufficiently tall. Injection of peroxidase into the stomach and ferritin into the coelom results in phagocytic uptake of these macromolecules by type I and type II choanocytes, respectively.

Cyclic localization change of Golgi apparatus in Sertoli cells induced by mature spermatids in rats.

Abstract: Previously we reported that the intracellular localization of the Golgi apparatus of rat Sertoli cells changes during the seminiferous epithelial cycle, and that the cyclic changes seem to be correlated to specific generations of germ cells. To ascertain which generations of germ cells are responsible for the cyclic changes, we determined the relative volume of the Golgi apparatus within the basal, mid, and apical cytoplasm of Sertoli cells in testes with and without mature spermatids. In normal adult rats, the Golgi apparatus was usually localized exclusively in the basal cytoplasm, whereas at stages VII-IX it increased remarkably in mid and apical cytoplasm, with a concomitant decrease in the basal cytoplasm. In young adult testes without spermatids at steps 15-19 of spermiogenesis (2nd layer spermatids), the Golgi apparatus was localized in the basal cytoplasm throughout the seminiferous epithelial cycle. Orchiopexy maintained for 35 days following 60 days of cryptorchidism allowed germ cells to regenerate to spermatids at steps 1-14 of sperminogenesis (1st layer spermatids), but failed to change the intracellular localization of the Golgi apparatus in Sertoli cells. At 50 days after orchiopexy, when all generations of germ cells appeared in the tubules, the cyclic changes in localization of the Golgi apparatus were restored similar to those in normal adult testes. These findings indicate that the cyclic change in localization of the Golgi apparatus in Sertoli cells is evoked by the presence of 2nd layer spermatids.

Ultrastructure of the mink parotid gland.

Abstract: Acini in the parotid gland of the North American mink (Mustela vision) are composed of seromucous cells that contain secretory granules of peculiar morphology. Many of the granules consist of a light matrix in which is embedded an inclusion made up of dense, frequently parallel rodlets in a fibrillar material of moderate density. Like the submandibular gland of the same animal, the tall cells of the parotid striated ducts contain numerous polygonal, often rhomboidal, crystalloids in their apical cytoplasm. These crystalloids are present equally in both sexes and are as abundant in the parotid as in the submandibular gland.

Complex Carbohydrate Histochemistry of the Lateral Prostate and Seminal Vesicle of the Guinea Pig

Abstract: A systematic histochemical study of the complex carbohydrates of the lateral prostate and seminal vesicle of the guinea pig has been made. The complex carbohydrates of the guinea pig male accessory sex glands were partially characterized by various conventional carbohydrate histochemical methods including periodic acid-Schiff, selective periodate oxidation-Schiff reaction, Alcian blue staining at pH 2.5 and 1.0, and high iron diamine. The results indicated that neutral glycoconjugates with 1,2-glycol groups and sialic acids were present in the luminal border and apical cytoplasm of the glandular cells, basement membrane and connective tissue in the lamina propria of the lateral prostate. Similar patterns were demonstrated in the seminal vesicle except that there were relatively fewer or no neutral carbohydrates in the apical cytoplasm of the vesicular epithelial cells. The epithelial basement membrane and connective tissue at the epithelial-stromal interface of both glands were rich in acidic and sulphated glycosaminoglycans. Partial characterization by bovine testicular hyaluronidase indicated the presence of chondroitin sulphates in the lamina propria of the glands.

Antidiuretic-hormone-induced morphological changes in the ampullary epithelium of the frog semicircular canal.

Abstract: Morphological changes induced by in vitro treatment with arginine-vasotocin, the frog antidiuretic hormone, were studied in the ampullary epithelium of the frog semicircular canal. Morphological changes appeared only in the apical side of the dark cells, while the basal part of these cells and the other cells lining the semicircular canal did not show any change. Changes consisted of the appearance of numerous small vesicles in the apical cytoplasm and the development of microvilli on the apical plasma membrane of the dark cells. These results suggest that arginine-vasotocin could play a role in the regulation of endolymph section.

Histochemistry of human urethral glands.

Abstract: Human urethral glands were reacted histochemically and immunohistochemically to identify glycopro-teins, some androgen metabolic enzymes, and VIP-like immunoreactivity. Neutral/acid mucosubstances were detected mainly in the apical cytoplasm of the principal cells. 3β-, 17β-, and 3α-hydroxysteroid dehydrogenase, G6PD, and 6PGD reactivity were intense in all the glandular epithelium. Small amounts of VIP-positive fibers were noted around the secretory elements.

Cryofixation, ultracryomicrotomy, and X-ray microanalysis of enterocytes from chick duodenum: Vitamin-D-induced formation of an apical tubulovesicular system

Abstract: New methods of tissue preparation were developed to study the morphology and distribution of calcium ions in duodenal enterocytes from normal, rachitic, and vitamin D-replete (either cholecalciferol [CC] or 1,25-dihydroxycholecalciferol [1,25-DHCC] treated) chicks. Frozen hydrated sections were prepared from cryofixed tissues by ultracryomicrotomy at – 125° C. Sections were subsequently freeze-dried by increasing the temperature to – 100°C. The latter temperature was maintained throughout both the structural and elemental analyses. In cells from normal, rachitic, and vitamin D-treated [CC] animals the brush border from lanthanum-infused tissues was electron dense and calcium-lanthanum positive by x-ray analysis. In the absence of lanthanum, i.e., sucrose-infused duodena, the microvilli were still calcium positive. In the terminal web region of normal and CC-treated enterocytes, numerous, apparently interconnected, tubules and vesicles were seen. Vacuole-like structures were also seen. Such structures were especially prominent in the enterocytes from the vitamin-treated [CC] animals. Except for the vacuoles, the tubules and vesicles were electron dense in the lanthanum-infused duodena, and clear in sucrose-infused tissues. In both instances, the structures were calcium positive. Similar, but even larger structures were seen below the terminal web. Here however, the tubules and vesicles seemed to be organized into multiple complex interconnecting networks, i.e., tubulo-vesicular complexes. Both the tubules and the vesicles seemed to be interconnected via smaller channel-like entities. The extensiveness of this structure was better appreciated in the enterocytes from lanthanum-infused tissues, where it appeared similar in structure and complexity to an en face view of the sarcoplasmic reticulum of skeletal muscle. These intestinal complexes were less well developed, decreased in number, and quite often absent, in the apical cytoplasm of absorptive cells from rachitic chicks. In the enterocytes from animals treated for 24 hours with 1,25-DHCC, the same highly developed tubulo-vesicular networks were again seen in the enterocyte apical cytoplasm. They were even more developed in the 1,25-DHCC-treated animals. All structures were intensely calcium positive in enterocytes from both the lanthanum- and the sucrose-infused preparations. Numerous endocytotic (pinocytotic) vesicles were seen at the lumenal plasmalemma. Similar structures were also apparent in the terminal web region of the 1,25-DHCC-treated enterocytes. Exocytotic vesicles were seen at the apical aspect of the lateral cell membrane, below the level of the junctional complex. All components of this unique system contained high concentrations of calcium. A similar, apically located, tubulovesicular complex has not been described in the enterocytes of conventionally prepared tissues obtained from either normal or vitamin D-replete duodena from rats, mice, chicks, etc. Thus it appears that this system, which could play a role in intestinal calcium transport, is extremely labile and apparently not preserved (maintained) by ordinary biological fixatives and/or by routine methods used for the preparation of tissues for electron microscopy. Therefore, cryofixation, ultracryomicrotomy, etc., may prove to be essential for the identification of transiently induced states of cell activation associated with hormones, growth factors, nerve impulses, etc. Since the dilated components of the tubulo-vesicular system described herein resemble (size, shape, density, etc.) the so-called calcium lysosomes previously described by our group in normal and vitamin D-replete chick enterocytes, the effect of 1,25-DHCC on certain lysosomal acid hydrolases was determined. After 24 hours treatment with 1,25-DHCC, there was a three to fourfold increase in the release of lysosomal enzymes such as acid phosphatase, cathepsin B, and B-N-acetyl-D-glucosaminidase into the medium of isolated enterocytes in comparison to untreated control cells. This would seem to indicate that the tubulo-vesicular network described here is comprised, at least in part, of lysosomes.

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.

Histochemical study on the bile duct system of normal Mongolian gerbils.

Abstract: The bile duct system of normal Mongolian gerbils was examined histochemically. The luminal surface membrane and apical cytoplasm of the biliary and gallbladder epithelial cells were stained with periodic acid-Schiff (PAS), alcian blue, pH 2.5 (AB) and high iron diamine (HID)-AB, and many epithelial cells of the common bile duct and gallbladder had weakly PAS-positive granular material in their supranuclear cytoplasm. Lectin-histochemically, these cells had binding sites to Concanavalia ensiformis (ConA), Dolichos biflorus (DBA), Glycine max (SBA), Ulex europeas-I (UEA-I), and Triticum vulgaris (WGA). On the other hand, the periductal glandular epithelial cells were not stained by any histochemical stainings. In addition to these light microscopic findings, the electron microscopic findings based on the periodic acid-silver methenamine method and avidin-biotin colloidal gold method for DBA and WGA suggested that the biliary and gallbladder epithelial cells of Mongolian gerbils secreted mucin with terminal sialic and sulfonic acid residues and that the lectin binding activity of mucin secreted from these cells was similar to that of mucin secreted from the periductal glandular epithelial cells of mice and rats.

Differentiation of epidermal cells in the regenerating planarian Dugesia japonica

Abstract: Distribution of the cytoplasmic components in planarian epidermal cells is highly polarized, just as in vertebrate epithelia. Differentiating epidermal cells of the planarian Dugesia japonica Ichikawa et Kawakatsu were found to have relatively conspicuous accumulations of microtubules in their apical cytoplasm. When colchicine, a microtubule-disrupting drug, was applied to regenerating worms, it reversibly disorganized the polarity of differentiating epidermal cells. Cytochalasin B, which depolymerizes actin filaments, had no significant effect on the polarization, however. Tubulin could be localized by immunocytochemistry in the cytoplasm of differentiating epidermal cells; this reaction was inhibited by treatment with colchicine for 20 h. These observations indicate that microtubules play a role in establishing polarity during cell differentiation.

Inhibitory effects of ionophore A23187 on the release of thyroid hormone and colloid reabsorption in mouse thyroid glands

Abstract: The effect of the ionophore A23187 on a. the release of thyroid hormone from perifused mouse thyroid glands and b. the morphological changes in follicular epithelial cells was evaluated. A23187 at a concentration of 5 mumol/l significantly inhibited both the TSH- and the forskolin-stimulated release of T3 and T4. In the presence of 3-isobutyl-1-methylxanthine or (4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone) RO 20-1724, A23187 did not affect the forskolin-stimulated release of cAMP, but did inhibit the release of T3 and T4 stimulated by forskolin. Light and electron microscopic evaluation of the follicular epithelial cells of mouse thyroid tissues following 1-h stimulation with forskolin showed numerous pseudopods engulfing luminal colloid of various size and the presence of reabsorbed colloid droplets in the apical cytoplasm. Quantitative electron microscopic analysis revealed that the addition of the ionophore A23187 reduced the number of reabsorbed colloid droplets to one eighth in follicular epithelial cells. These observations suggest that the increase in intracellular Ca2+ induced by the ionophore A23187 inhibits the TSH-stimulated thyroid hormone release independently of the cAMP level, and that the suppression of thyroid hormone release may be due to an inhibition of colloid reabsorption.

of epidermal cells in the regenerating planarian Dugesia japonica

Abstract: Distribution of the cytoplasmic components in planarian epidermal cells is highly polarized, just as in vertebrate epithelia. Differentiating epidermal cells of the planarian Dugesia japonica Ichikawa et Kawakatsu were found to have relatively conspicuous accumulations of microtubules in their apical cytoplasm. When colchicine, a microtubule-disrupting drug, was applied to regenerating worms, it re­ versibly disorganized the polarity of differentiating epidermal cells. Cytochalasin B, which depolymerizes actin filaments, had no significant effect on the polarization, however. Tubulin could be localized by immunocytochemistry in the cytoplasm of differentiating epidermal cells; this reaction was inhibited by treatment with colchicine for 20 h. These observations indicate that microtubules playa role in estab­ lishing polarity during cell differentiation.

Clinical Applications of Thyroid Peroxidase Autoantibody Determination

Abstract: In thyroid autoimmune disorders circulating autoantibodies (anti-M Ab) are frequently detected reacting with the thyroid microsomal antigen (M-Ag), a membrane protein associated with the microsomal subcellular fraction and located mainly in the apical cytoplasm and on the plasma membrane of thyroid follicular cells [1–6]. Recent investigations have provided biochemical, immunological, and molecular evidence that thyroid peroxidase (TPO) is the main and possibly the only autoantigenic component of thyroid microsomes [6–13].