GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Secretion of fucosylated oligosaccharides related to the H antigen by human gastric cells (1998)
    Springer
    Histochemistry and cell biology 110 (1998), S. 295-301 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Although the role of the blood group antigens in the gastrointestinal tract is not well understood, alterations in blood group-related antigens have been described in some pathological processes. Thus, the knowledge of their expression under normal conditions is of special interest. Those individuals expressing their ABO blood group in exocrine epithelia and secretions are called secretors. The aim of the present study was the localization of H antigen expression in the normal human gastric epithelial cells of non-O blood group individuals. For this, a monoclonal anti-H antibody was examined by immunocytochemical methods at both the light and electron microscopic levels. In combination with enzymatic and chemical treatments, the nature of the oligosaccharide chains containing the H antigen was characterized. The selected cases were four A secretors, three A non-secretors, and three B non-secretors. The labeling of the anti-H antibody in the human stomach is described, irrespective of the blood group of the individuals. The staining was abolished when O-linked oligosaccharides were removed. Since commercially available anti-H antibodies usually also recognize other H-related antigens, the labeling of the antibody by H-related antigens cannot be dismissed. Our findings suggest the existence of H or H-related antigens in the O-linked oligosaccharides of the secretory granules of the surface, gastric pit, mucous neck, and transitional cells of the fundic mucosa, and in the intracellular canaliculi and tubulovesicular system of parietal cells. The H or H-related antigens were also localized in the apical membrane of all the cell types of the epithelial cells of the human fundic mucosa. The overall distribution of the H or H-related antigens in the stomach in non-O blood group individuals suggests the constitutive expression of an α(1,2)fucosyltransferase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004180050291
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Analysis of the distribution of glycoconjugates in the digestive gland of the bivalve mollusc Mytilus galloprovincialis by conventional and lectin histochemistry (1997)
    Springer
    Cell & tissue research 288 (1997), S. 591-602 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Carbohydrates ; Glycoconjugates ; Digestive tract ; Connective tissue ; Lectin histochemistry ; Mytilus galloprovincialis (Mollusca)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. We examined the distribution and pattern of reactivity of a panel of 16 lectins in the digestive gland of the bivalve mollusc Mytilus galloprovincialis at the light-microscopic level. Various chemical treatments were applied in combination with lectins to differentiate between N- and O-linked oligosaccharides. Several control reactions were carried out, including replacement of lectins by buffer and incubation with their specific competitive inhibitors. Some lectins reacted selectively with particular cell types, thus revealing a cell-specific glycoconjugate distribution pattern which is possibly related to the metabolic role of each cell type in the digestive gland. Glycoconjugates containing glucosamine, mannose, and sulfated galactose were associated with the endolysosomal system of digestive cells. These glycoconjugates were also found in small vesicles randomly distributed in the cytoplasm of adipogranular cells in the connective tissue. However galactosamine residues appeared to be associated mainly with basophilic cells. Fucose residues did not exhibit a cell-specific distribution and appeared in small amounts homogeneously distributed throughout the digestive gland tissue. Conventional histochemical reactions for carbohydrate detection revealed moderate amounts of periodic-acid–Schiff-positive, neutral carbohydrates widely distributed in digestive and connective tissues. Among the acid carbohydrates, most cell types contained complex sulfated carbohydrates, but not carboxylated ones; this agreed well with the complete lack of sialic acid residues in all cell types studied, as observed by lectin histochemistry.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050845
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Lectin histochemical localization of N- and O-linked oligosaccharides during the spermiogenesis of the urodele amphibian Pleurodeles waltl (1999)
    Springer
    Glycoconjugate journal 16 (1999), S. 639-648 
    Details
    ISSN: 1573-4986
    Keywords: lectin histochemistry ; amphibian ; testis ; spermiogenesis ; acrosome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The aim of this work is the characterization of the glycoconjugates of the spermatids during the spermiogenesis of the testis of an urodele amphibian, Pleurodeles waltl, by means of lectins in combination with several chemical and enzymatic procedures, in order to establish the distribution of N- and O-linked oligosaccharides in these cells. The acrosome was the most relevant lectin-labeled structure. The O-linked oligosaccharides contained DBA- and SBA-positive GalNAc, AAA-positive Fuc and PNA-positive Galβ1,3GalNAc. Sialic acid was scarcely observed, the Neu5Acα2,-3Galβ1,4GlcNAc sequence was found in N-linked oligosaccharides. Additionally, N-linked oligosaccharides containing HPA-positive GalNAc and AAA-positive Fuc were found. Moreover, with some lectins the acrosome showed a variable composition of the oligosaccharides in the different steps of the sperm maturation. Some residues were found only in the early steps in maturating acrosome, while others were in the later steps, showing that acrosomal glycoconjugates are modified during acrosome development in spermiogenesis. The changes observed during acrosome maturation suggest the existence of a predetermined pattern of storage of the acrosome components and a progressive compression of them.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007081101470
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Cytochemical characterization of oligosaccharide side chains of the glycoproteins of rat zona pellucida: An ultrastructural study (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 239 (1994), S. 137-149 
    Details
    ISSN: 0003-276X
    Keywords: Cytochemistry ; Lectin ; Rat zona pellucida ; Oocyte ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Background: The zona pellucida (ZP), an extracellular matrix which surrounds mammalian oocytes, is formed by different glycoproteins. Several studies have revealed that carbohydrate residues present in glycoproteins of ZP play a key role in the sperm-egg recognition. However, the origin and the biochemical composition of ZP remain to be completely resolved.Methods: ZP glycoproteins from rat ovarian follicles were investigated at light and electron microscopic level by the application of lectins conjugated to peroxidase, digoxigenin, and colloidal gold in combination with enzyme and chemical treatment. A quantitative analysis was also performed.Results: ZP shows reactivity to WGA, DSA, LFA, AAA, RCA I, and MAA. SBA and PNA showed a variable reactivity ranging from negative to strongly positive. A uniform pattern of binding throughout ZP was observed with DSA, Con A, AAA, MAA, and LFA. However, labeling by RCA I and SBA was higher in the outer ZP while PNA and WGA showed a higher binding in the inner ZP. Lectin reactivity was detected in cortical granules, endoplasmic reticulum, Golgi apparatus, vesicles, and multivesicular bodies of oocytes.Conclusions: ZP contained the terminal disaccharides Galβ1,4GlcNAc, Galβ1,3GalNAc, and GalNAcβ1,3Gal and the trisaccharides Neu5Acα2, 3Galβ1,4GlcNAc, Neu5Ac-Galβ1,3GalNAc, and Neu5Ac-GalNAcβ1,3Gal sequences. The occurrence of Fucose residues α 1,6 linked to the inner core region of N-linked glycoproteins of ZP was demonstratd by the use of several fucose-specific lectins. Methylation-saponification treatment in combination with lectin cytochemistry reveals that Gal, GalNAc, and polyllactosamine residues of rat ZP glycoproteins contain sulphated groups. The reactivity observed in ooplasmic vesicles was similar to that of ZP, thus suggesting that the oocyte is the site of synthesis of ZP glycoproteins. © 1994 Wiley-Liss, Inc.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1092390204
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...