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B Tandler

Publications and source records attributed to B Tandler.

At least 73 records · Page 4Linked to original sources
PubMed1989

Dense-cored vesicles and unusual lamellar bodies in type III gustatory cells in taste buds of rabbit foliate papillae.

Some type III cells in taste buds of rabbit foliate papillae have greatly increased numbers of dense-cored vesicles. Such cells also contain unusual lamellar bodies that resemble those in alveolar type II cells; they consist of alternating dense and light layers with a periodicity of about 4.4 nm. The precise relationship between the vesicles and the lamellar bodies is unknown.

Animals↗
PubMed1989

Modified endoplasmic reticulum in taste bud cells of the Japanese monkey.

Type III cells (receptor cells) in taste buds of vallate papillae in the Japanese monkey often have one or more cytoplasmic bodies composed of modified smooth endoplasmic reticulum in the form of concentric smooth-surfaced cisternae, up to 18 in number. The most peripheral cisternae may be in continuity with rough endoplasmic reticulum (RER). Type II cells have dilated RER cisternae that often contain crystalline plates with an axial periodicity that ranges from 17 to 27 nm. These observations show that both type III and type II cells of the Japanese monkey possess the cytoplasmic machinery to carry out several secretory functions.

Animals↗
PubMed1989

Viruses and annulate lamellae in Friend erythroleukemia cells.

Virus formation in a clone of murine undifferentiated Friend erythroleukemia cells was examined by electron microscopy. Budding C-type particles were present at the cell surface. The principal site of intracisternal particle production was in elements of rough-surfaced endoplasmic reticulum disposed about the periphery of stacks of annulate lamellae. Serial sections demonstrated that these virus-laden cisternae were in direct continuity with the annulate lamellae. In addition, intracisternal particles occurred in membranous honeycomb structures present in the cytoplasm of many cells. Viral elaboration also was associated with stacks of cisternae of endoplasmic reticulum that were devoid of ribosomes, but that were coated with an extensive and continuous layer of dense material. In some instances, the outer nuclear membrane was coated with the same dense substance. It appears that in Friend erythroleukemia cells, a very substantial portion of their cytomembranes is devoted to synthesis of intracisternal particles.

Animals↗
PubMed1988

Ultrastructural observations on human sublingual gland.

That part of the human sublingual gland that corresponds in morphology to the conventional description of this organ presented in most histology texts (probably the major sublingual gland, in contradistinction to the aggregated small glands that compose the minor sublingual glands) was studied by electron microscopy. The gland is mixed, with slightly more mucous elements than seromucous ones. The mucous cells are arranged in tubules that usually are capped by seromucous demilunes. Seromucous cells also form occasional acini or may be scattered in the walls of the mucous tubules. The appearance of the mucous cells varies with the stage of the secretory cycle that they may be in. Their secretory droplets increase in number and progressively compress cytoplasmic organelles. Filamentous bodies also may be present. Based on secretory-granule substructure, four different kinds of seromucous cells can be recognized; these may be a morphological expression of asynchronous synthesis of different secretory proteins. The duct system is an abbreviated one compared to the other major salivary glands. The first duct segments, into which the mucous tubules drain, are similar to intercalated ducts. Larger ducts contain mitochondria-rich cells but lack the basal striations that characterize striated ducts. The paucity of typical striated ducts may be correlated with the elaboration of sodium-rich saliva by the human sublingual gland.

Adult↗
PubMed1988

Goblet cell isolation from cat trachea: a comparison of methods.

Goblet cell hyperplasia and metaplasia may be important in the pathogenesis of many respiratory diseases. To study the intracellular mechanisms of mucin synthesis, a purified goblet cell preparation is necessary. We have compared different methods of cell dissociation using cat trachea, a source rich in goblet cells. The most successful method used EDTA to loosen the basement membrane and 1% pronase to dissociate the epithelial cells. Goblet cells recovered from a linear Percoll gradient showed preservation of their ultrastructural detail, trypan blue exclusion, oxygen consumption, and synthesis of a high molecular weight compound resistant to hyaluronidase degradation, consistent with mucous glycoprotein. This method allows the isolation of adequate numbers of purified goblet cells for further study of goblet cell synthetic processes.

Animals↗
PubMed1987

Forms of a self associating autoantibody complex between a monoclonal human IgG1 and human serum albumin.

The mode of association of an unusual human autoantibody complex, composed of a monoclonal immunoglobulin, Tu IgG, and human serum albumin was investigated. A crystalline complex forms from these components in the cold and we have shown that it consists of IgG and albumin in a 1:2 molar ratio [Jentoft et al., Biochemistry 21, 289-294 (1982)]. The crystalline complex was analyzed by electron microscopy and the soluble natural complexes (formed by dissolving the crystals at 20 degrees C) were studied by sedimentation velocity. The sedimentation studies demonstrated that the soluble Tu IgG-albumin complexes are in equilibrium with free Tu IgG and albumin molecules and that the major soluble sedimenting species has a S20,w value of 12.5S. At a constant concn of complex, the size of the sedimenting complex can be reduced by lowering the pH, increasing the ionic strength, or adding CaCl2, citrate, ascorbate or urea. These intermediate, soluble forms have S20,w values that are consistent with 1:1 and 1:2 Tu IgG-albumin complexes. Parameters of repeat distances and angles that were obtained from electron micrographs of the crystalline form of the Tu IgG-albumin complex were used to propose a model for the 12.5S species and were also incorporated into a three-dimensional model for the complex. The 12.5S complex is proposed to form by dimerization of the 1:2 Tu IgG-albumin complex via interactions of albumin with the Fc region of the antibody. The 12.5S dimer may be the nucleating species for subsequent rapid associations that lead to spontaneous formation of crystals. In the proposed model for the Tu IgG-albumin crystals, the angle between the Fab arms of each Tu IgG molecule is 90 degrees, the antigenic determinant on the albumin is located near one end of the long axis of the cylindrical molecule, the site of interaction with Fc is located at the other end of the cylinder, and the CH3 domain of the IgG contains the binding site for albumin that is responsible for the formation of the dimeric 12.5S species. A series of sedimentation velocity experiments suggest that the association between the CH3 domain of IgG and albumin requires the prior formation of the antibody-antigen complex.

Antibodies, Monoclonal↗
PubMed1987

Salivary gland changes in disease.

Ultrastructural alterations occurring in human salivary glands as a result of a variety of diseases are described. Major changes in these organs in cases of cystic fibrosis are probably the result of duct blockage, as indicated by study of chronically inflamed salivary glands. A new disease of salivary glands is reported in which parotid serous granules are distorted by bundles of fine filaments, which may be due to the untoward polymerization of a secretory protein, perhaps proline-rich protein. Finally, a clear-cell adenocarcinoma of palatine gland origin is described in which the nuclei display complex pseudoinclusions and the cytoplasm contains numerous herpes-type viruses.

Child↗
PubMed1987

Modified smooth endoplasmic reticulum in type II cells of rabbit taste buds.

Type II cells of taste buds from rabbit foliate papillae are characterized by a widespread system of smooth endoplasmic reticulum (SER), usually in the form of a loose network. In some cells, the SER is tightly compacted into a juxtanuclear aggregate that is continuous with the perinuclear space and that appears to merge with the Golgi complex. In other type II cells, the SER is in a honeycomb arrangement. Where type II cells confront nerves, they may have extensive smooth-membraned subsurface cisternae. The presence of manifold forms of SER in type II cells suggests that these cells may have a variety of secretory functions.

Animals↗
PubMed1986

Ultrastructure of the submandibular gland in the rabbit.

The secretory endpieces of the rabbit submandibular gland are unusual in that they consist of seromucous acini (not demilunes) that empty into serous tubules that in turn drain into intercalated ducts. Seromucous granules consist of a moderately dense spherule in a fibrillogranular matrix. Serous granules contain a feltwork of filaments, which are liberated as a tangled skein during exocytosis. Peculiar granulated cells that have secretory granules of complex morphology are present at each end of the serous tubules. Intercalated ducts are, cytologically speaking, relatively simple, but the duct cells may contain a few oblong secretory granules. Striated ducts are typical in structure, although postfixation with ferrocyanide-reduced osmium reveals significant amounts of glycogen in the basal processes. Modified mitochondria are present in striated duct cells, but their frequency varies from rabbit to rabbit. Such mitochondria contain either an array of parallel, rigid cristae linked by intermembranous bridges, or a bundle of helical filaments within an expanded crista. Interspersed with the striated duct cells, especially near the duct origin, are some highly vacuolated cells with sparse mitochondria. Excretory ducts consisting of stratified columnar (sometimes pseudostratified) epithelium often show bleb formation of the luminal surface of the tall cells.

Animals↗
PubMed1986

Gap junctions in rat sublingual gland.

Gap junctions were observed in rat sublingual gland to link serous cells to serous cells, mucous cells to mucous cells, and myoepithelial cells to myoepithelial cells. In addition to connecting homologous cells, gap junctions were present between conterminous serous and mucous cells. Since the rat sublingual gland is innervated solely by parasympathetic nerves, the presence of gap junctions between disparate secretory cell types raises the possibility that serous and mucous cells in this organ secrete simultaneously in response to parasympathetic stimulation.

Animals↗
PubMed1986

Dividing type II cell in rabbit taste bud.

Examination of rabbit foliate papillae by electron microscopy revealed for the first time the existence of a dividing cell within a taste bud. The ultrastructure of this cell was in keeping with that of type II cells of the sort located in the center of taste buds. Whether this cell is capable of differentiating into other cell types is still unclear.

Animals↗
PubMed1986

Papillary morphology of the tongue of the American chameleon: Anolis carolinensis.

Based on regional differences in surface morphology, the dorsum of the tongue of Anolis carolinensis can be subdivided into four distinct zones. The first quarter of the tongue is relatively smooth, whereas the second and fourth quarters are festooned with closely packed cylindriform papillae, which are covered by typical parakeratotic stratified squamous epithelium. The third quarter of the tongue is covered by papillae of novel morphology that we have named "plumose papillae." These are composed of a slender connective tissue core covered by stratified squamous epithelium from whose surface numerous elongated cells radiate. These "plume cells" are about 30-40 microns long and have an extremely irregular nucleus in their expanded terminus. Their stalks are affixed by desmosomes to the deeper cells of the epithelium, and their free surfaces are covered by intricately patterned microplications. Their cytosol contains a dense web of 100-A cytofilaments that may be involved in maintaining the peculiar morphology of the cells. Regardless of type, all lingual papillae of A. carolinensis contain a single longitudinally oriented skeletal muscle fiber that originates from the underlying lingual muscles, raising the possibility that the papillae can be moved at will. The plumose papillae and their retinue of plume cells are unique morphological structures that may be important in mastication and deglutition of food.

Animals↗
PubMed1986

Isolation of plasma membranes from Drosophila embryos.

Cell surface components probably play an important role in early embryonic development. However, hardly any information is available on the structure or regulation of expression of the corresponding genes. As a first step in approaching this issue, we devised a procedure to obtain enriched plasma membranes from embryonic Drosophila cells. Membranes are fractionated according to two independent physical parameters: size, using velocity gradient centrifugation and density, using isopicnic gradient centrifugation. The final membrane fraction is enriched by 6 to 8 fold with respect to the plasma membrane enzyme marker Na+/K+ ATPase and substantially depleted of the mitochondrial enzyme marker cytochrome C oxidase. Two-dimensional polyacrylamide gel electrophoresis of the purified membranes reveals enrichment for specific proteins and electron microscopy reveals membrane vesicles in abundance. The enriched fraction should be suitable for the preparation of antibody probes that recognize cell surface components.

Animals↗
PubMed1986

Heterogeneous response of subsarcolemmal heart mitochondria to calcium.

The Ca2+ -uptake capacity of two distinct populations of rat heart mitochondria was characterized by monitoring Ca2+ movements directly (using both 45Ca and dual-wavelength spectroscopy) and indirectly (monitoring effects of Ca2+ on respiration, enzyme release, and morphology). Interfibrillar mitochondria accumulated up to 930 nmol/mg protein, whereas the capacity of the subsarcolemmal mitochondria for Ca2+ uptake was limited to 620 nmol/mg protein. In both mitochondrial populations, uptake of the maximal amount of Ca2+ was accompanied by increased proton permeability and subsequent release of the accumulated Ca2+. Even when calcium was taken up and apparently retained by the subsarcolemmal mitochondria, resting respiratory rates increased. Morphological examination of these mitochondria revealed that, although the majority of mitochondria were in the aggregated, energized conformation, a considerable number were disrupted. These damaged mitochondria were probably responsible for the increased resting respiratory rates. No net release of calcium was observed, however, since the intact mitochondria could take up any calcium released by the damaged mitochondria. Morphological disruption of this subset of subsarcolemmal mitochondria was accompanied by release of not only cytochrome c but also of mitochondrial marker enzymes into the extramitochondrial milieu. In contrast, the interfibrillar mitochondria were relatively unaffected in terms of morphology and marker enzyme release, even when their capacity to retain calcium was exceeded.

Animals↗
PubMed1986

Ultrastructure of the submandibular gland in 2 species of macaques.

The ultrastructure of the submandibular glands was studied in 2 species of macaques (Macaca mulatta and Macaca irus). The glands, which were identical in both species, were predominantly serous, but contained scattered mucous acini. The serous cells contained 1 of 2 morphologically distinct secretory granules of complex substructure, whereas mucous droplets were relatively simple in structure. Other parts of the macaque glands were similar to their counterparts in other primates. The close resemblance of the serous granules to each other in the 2 species studied and to 3 other macaque species previously described by others suggests that these monkeys are taxonomically closely related.

Animals↗
PubMed1986

Ultrastructure of the angularis oris salivary gland in the house sparrow.

The angularis oris gland, an avian salivary gland that lies beneath the zygomatic arch, was studied in the house sparrow by means of light and electron microscopy. The gland consists of lobules composed of epithelial tubules and folds on a delicate connective tissue framework. The lobules are drained by large channels to form an intraglandular duct, which becomes the main extraglandular duct. The tubules, folds, and all ducts are covered by pseudostratified epithelium that shows progressive changes from the blind ends of tubules to the duct system. At the closed end of the tubules, the tall cells contain an aggregation of closely packed mucous droplets; their mitochondria are long and slender. As the epithelium nears the duct system, the mucus content of the tall cells is reduced and the mitochondria, which are increased in number, are ovoid. The lateral borders of the cells are complexly interlocked. In the ducts, mitochondria-rich cells with extensive lateral interfoliation comprise the major cell type; some of these cells contain a few mucous droplets at their apices. The basal cells of the pseudostratified epithelium have the same basic structure regardless of their location. These pyramidal cells have abundant cytofilaments and are joined to the basal lamina by many hemidesmosomes. Despite the absence of clear-cut morphological zonation, the angularis oris may function in a manner that is analogous to mammalian salivary glands: secretory cells produce the organic component of the saliva, mucus, while the mitochondria-rich cells with their extensive lateral membranes probably resorb electrolytes to render the final saliva hypotonic.

Animals↗