Browsing by Subject "Sugar residues"

Now showing 1 - 5 of 5
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    Ageing of the human oviduct: lectin histochemistry
    (Murcia : F. Hernández, 2001) Gheri, G.; Noci, I.; Sgambati, E.; Borri, P.; Taddei, G.; Gheri Bryk, S.
    The aim of the present research was to investigate the changes of the sugar residues in the oviduct in the course of ageing in postmenopausal women vs normally menstruating women, by means of lectin histochemistry. Twenty asymptomatic postmenopausal women (48- 83 years old) were recruited among patients who underwent a vaginal hysterectomy. Eight normally menstruating women were recruited as controls. Fragments of Fallopian tubes (pars ampullaris) were fixed in 10% formalin and routinely processed. The sections were labelled with HRP-lectins (PNA, SBA, DBA, WGA, Con A, LTA, UEAI). Some sections were pre-treated with neuraminidase prior to staining with HRP-lectins. Among the postmenopausal patients, our histochemical data showed that there was no difference in the localization and distribution of sugar residues of glycoconjugates as detected by various HRP-lectins. Moreover, our results demonstrated that the oviductal epithelium is characterized by apical reactivity in both ciliated and non-ciliated cells. In the course of ageing, the ciliated cells changed their morphology from bathyprismatic to large and rounded shape. ConA lectin reacted intensely with such highly degenerating ciliated cells and could be considered a marker of these cells. The degenerating ciliated cells are also characterized by the absence of sialic acid. In comparison with the sugar residues present in the control group, the oviductal epithelium of postmenopausal women is characterized by the loss of reactivity with DBA, WGA and ConA. Moreover, PNA reactive material was present at the free border of the ciliated and non-ciliated cells. The latter findings were statistically confirmed and could be considered strictly related to the ageing process.
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    Characterization of the glycoconjugate sugar residues in developing chick esophageal epithelium
    (Murcia : F. Hernández, 1993) Gheri, G.; Gheri Bryk, S.; Sgambati, E.; Gulisano, M.
    The development of the esophagus in the chick embryo is characterized by remarkable morphological changes especially at the level of the epithelium. Using horseradish peroxidase-conjugated lectins (DBA, PNA, SBA, WGA, ConA, LTA, UEAI) we have studied, at the level of the esophagus of chick embryos from the 8th to the 21st day of incubation and of 1- and 2-day-old chicken, the evolution of the saccharidic moieties of glycoconjugates, which precedes andlor is concomitant with the epithelial morphological transformations. We have found differences in content and cellular distribution of oligosaccharides during the histogenetic processes which characterize the lining and glandular epithelium. Before the appearance of cilia and mucus secretion at the bathyprismatic epithelial cells, the sugar residues D-galactose-(B 133)-N-acetyl-Dgalactosamine, B-N-acetyl-D-galactosamine and a-Lfucose were detected only at the luminal cell surface. These oligosaccharides were probably involved in giving rise to the polarization of the esophageal epithelial cells. The esophageal gland mucus was first characterized by the presence of a-L-fucose and afterwards also by the presence of D-galactose-(Bl33)-N-acetyl-Dgalactosamine, D-glucosamine and sialic acid.
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    IIThe glycoconjugate sugar residues of the sessile and motile cells in the thymus of normal and Cyclosporin-A-treated rats: lectin histochemistry
    (Murcia : F. Hernández, 2002) Gheri, G.; Gheri Bryk, S.; Riccardi-Arbi, R.; Sgambati, E.; Cirri Borghi, M.B.
    It is well known that cell surface glycoconjugates play a determinant role in cellular recognition, cell-to-cell adhesion and serve as receptor molecules. T-lymphocytes are in strict contact with the thymic epithelial cells, which control their process of maturation and proliferation. On the other hand the normal maturation of the epithelial cells is believed to be induced by T-lymphocytes. For these reasons we have studied the glycoconjugates saccharidic moieties of the sessile and motile cells in the thymus of normal male albino Wistar rats and their changes following cyclosporin-A treatment, using a battery of seven HRPlectins. Cytochemical controls were performed for specificity of lectin-sugar reaction. Some sections were pre-treated with neuraminidase prior to staining with HRP-lectins. Our results have demonstrated, in the control rats, a large amount and a variety of terminal and subterminal oligosaccharides within and/or on the epithelial thymic cells and in macrophages. After cyclosporin-A treatment, among the thymic epithelial cells, the subcapsular, paraseptal and perivascular cells showed the loss of some sugar residues, which characterized the same cells in the intact thymus. Some hypotheses are reported on the role played by the glycoconjugate sugar residues in control and cyclosporin-A treated rats.
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    Lectin binding in the human endometrium in early luteal phase following controlled ovarian hyperstimulation
    (Murcia : F. Hernández, 1998) Gheri, G.; Gheri Bryk, S.; Taddei, G.; Borri, P.; Noci, I.
    A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties on the endometrial epithelium and stroma in 12 women undergoing controlled ovarian hyperstimulation (COH) for in-vitro fertilisation for embryo transfer (IVF-ET) in early luteal phase. 7 control subjects were also evaluated. For this purpose a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEA I) was used. Cytochemical controls were performed for specificity of lectin-sugar reaction. As far as the endometrial glands and stroma are concerned, the obtained data showed no differences in the endometrial lectin binding between the subjects of the control group and the ones undergoing COH, with the exception of PNA reactivity at the level of the apical portion of the glandular cells, which was detected only in COH women. It is noteworthy that, although the endometrial dating using the Noyes's criteria showed marked dissynchronies between the stroma and the glands in COH subjects, a uniformity of lectin binding, revealing the same type and localization of terminal oligosaccharides, was observed in all the examined subjects. The uniformity in distribution of the sugar residues detected in the endometrial specimens following COH might be due to the massive FSH and/or hCG treatment which probably determines an endometrial environment almost equal in all the examined subjects. In all the treated subjects reactivity with sialidase-WGA and ConA, revealing the presence of Nacetyl -D-glucosamine and D-mannose respectively, was detected at the level of the lining epithelium.
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    Sugar residues content and distribution in atrophic and hyperplastic postmenopausal human endometrium: lectin histochemistry
    (Murcia : F. Hernández, 1996) Gheri, G.; Gheri Bryk, S.; Taddei, G.; Moncini, D.; Noci, I.
    A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties of the human postmenopausal endometrium (14 atrophic and 15 hyperplastic). For this purpose a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEA I) was used. No differences in lectin binding between atrophic and hyperplastic endometria were observed. This investigation allowed us to provide a basic picture of the oligosaccharidic distribution in postmenopausal endometria. The data on the saccharidic distribution at the postmenopausal endometria showed a large amount of sugar residues at all the investigated sites, i.e. the lining and glandular epithelium, the stroma and the vessels (capillary and large vessels). Furthermore, at the endometrial lining epithelium, at the glands and at the wall of the blood vessels of some postmenopausal women the presence of a-L-fucosyl residues which bind via a (1-6) linkage to penultimate glucosaminyl residues andtor difucosylated oligosaccharides was demonstrated for the first time.