Biomedical subjects

G Gheri

Publications and source records attributed to G Gheri.

At least 19 recordsLinked to original sources

PubMed2004

Distributional map of the terminal and sub-terminal sugar residues of the glycoconjugates in the prepubertal and postpubertal testis of a subject affected by complete androgen insensitivity syndrome (Morris's syndrome): lectin histochemical study.

In the present research we have investigated the distribution of the sugar residues of the glycoconjugates in the prepubertal and postpubertal testes of a subject with Morris's syndrome (CAIS, Complete Androgen Insensitivity Syndrome). For this purpose a battery of six horseradish peroxidase-conjugated lectins was used (SBA, PNA, WGA, ConA, LTA and UEAI). We have obtained a complete distributional map of the terminal and sub-terminal oligosaccharides in the tunica albuginea, interstitial tissue, lamina propria of the seminiferous tubules, Leydig cells, Sertoli cells, spermatogonia, mastocytes and endothelial cells. Furthermore the present study has shown that a large amount of sugar residues were detectable in the prepubertal and postpubertal testes but that some differences exist with particular regard to the Sertoli cells. The Sertoli cells and the Leydig cells of the retained prepubertal testis of the patient affected by Morris's syndrome were characterized by the presence of alpha-L-fucose, which was absent in the retained prepubertal testis of the normal subjects. Comparing the results on the postpubertal testis with those obtained on the same aged testis of healthy subjects we have demonstrated that alpha-L-fucose in the Sertoli and Leydig cells and D-galactose-N-acetyl-D-galactosamine in the Leydig cells are a unique feature of the subject affected by Morris's syndrome. D-galactose (ss1,3)-N-acetyl-D-galactosamine and sialic acid, which are present in the Leydig cells of the normal testis were never observed in the same cells of the postpubertal testis of the CAIS patient.

Adolescent↗

PubMed2003

Lectin binding in the human umbilical cord from normally grown pregnancies and from pregnancies complicated by intra-uterine growth retardation with absent or reversed diastolic flow.

The content and the distribution of the glycoconjugate sugar residues were investigated in the human umbilical cord from normally grown pregnancies and from pregnancies complicated by intra-uterine growth retardation with absent or reversed flow in the umbilical artery. The gestational age range was 29-41 weeks. For this purpose, a battery of eight horseradish peroxidase conjugated lectins was used (ConA, WGA, PNA, SBA, DBA, LTA, UEA I, and OOA; see text). Our data showed that in both study groups ConA, WGA and PNA (after neuraminidase digestion) and LTA, UEA I, and OOA reacted with Wharton's jelly and vessels of the umbilical cord from the first weeks of gestation considered. SBA reactivity was observed only in the amniotic epithelial cells of the jelly and in the endothelial cells of the vessels. The reactivity with the most part of the lectins decreased or was lacking in the various components of the umbilical cord between 39 and 41 weeks of gestation in the normal group and between 36 and 37 weeks of gestation in the pathological one. Moreover, the intensity of reactivity with ConA, WGA and PNA (after neuraminidase digestion) and LTA, UEA I, and OOA in the normal group and with PNA (before and after neuraminidase digestion) and LTA and OOA in the pathological one was stronger in the peripheral portion of the jelly with respect to the adventitial one. The reactivity with ConA and UEA I was stronger in the vein than in the arteries in both study groups. Some hypotheses are reported on the role played by the sugar residues in the normal and pathological umbilical cords.

Concanavalin A↗

PubMed2003

Lectin binding in the human foetal testis.

In the present study we have investigated the oligosaccharidic content of the glycoconjugates within the human foetal testis starting from its earliest differentiation phase (8, 10 and 12 weeks of gestation). To this purpose we have used a battery of six horseradish peroxidase-labelled lectins (SBA, PNA, WGA, UEAI, LTA and ConA). We have obtained a complete distributional map of the sugar residues of the glycoconjugates in the coelomic mesothelium, tunica albuginea, pre-Sertoli cells, pre-gonocytes, Leydig cells, basement membrane of the sex cords, interstitial tissue, mastocytes and endothelial cells of the capillary vessels. Since the beginning of the testis differentiation phase the cells of the coelomic mesothelium showed a large amount of sugar residues. In the pre-Sertoli cells and in the pre-gonocytes a role played as structural molecules by some oligosaccharides could be hypothesized. D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, sialic acid, N-acetyl-D-glucosamine and alpha-D-mannose could be involved in inducing and maintaining the cellular activity of the Leydig cells.

Cell Differentiation↗

PubMed2002

The glycoconjugate sugar residues of the sessile and motile cells in the thymus of normal and cyclosporin-A-treated rats: lectin histochemistry.

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 HRP-lectins. 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.

Animals↗

PubMed2001

Ageing of the human oviduct: lectin histochemistry.

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.

Aged↗

PubMed2000

Glycoconjugate sugar residues in the chick embryo developing lung: a lectin histochemical study.

A lectin histochemical study was performed to investigate the distribution and changes of the oligosaccharidic component of the glycoconjugates in the lung of chick embryos, of 1-day-old chick, and of the adult animal. For this purpose, a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, Con A, LTA, and UEA I) were employed. During the first phase of parabronchi and atria formation, D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, beta-N-acetyl-D-galactosamine, D-glucosamine, alpha-D-mannose, and sialic acid, present at the level of the surface and of cytoplasmic granules of the lining epithelial cells, seem to play a role in regulating morphogenetic phenomena. In the subsequent phases, the parabronchial lumen and the atrial cavities were characterized by the presence of lectin-reactive material rich in terminal D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, beta-N-acetyl-D-galactosamine, D-glucosamine and alpha-D-mannose. From day 18 onwards and immediately after hatching, the free border of the cells lining the air capillaries was characterized by the presence of beta-N-acetyl-D-galactosamine and alpha-D-mannose. The appearance of these sugar residues was concomitant with the beginning of respiratory activity.

Aging↗

PubMed2000

Lectin binding in the ovary of the chick embryo and newborn.

The content, distribution and changes of the glycoconjugates sugar residues in the ovaries of chick embryos, from the 8th day of incubation to hatching and in 1-day old chick, were investigated. For this purpose, a battery of seven HRP-conjugated lectins was used (DBA, SBA, PNA, ConA, WGA, LTA and UEA I). Our data showed that SBA was a marker of the most immature oogonia in the ovarian cortex and medulla. The reactivity with ConA appeared to characterize the cells immediately prior to as well as during the meiotic division, as demonstrated by the presence of alpha-D-mannose at the "Balbiani bodies" in the oogonia of the ovarian cortex. The detection of Con A and SBA reactivity corresponded to maturative stages of the early oogonia in different cortical zones of the chick ovary. Our data also revealed that PNA seemed to be a marker of the degenerating oogonia located in the ovarian medulla. Moreover, PNA binding was a characteristic finding in the endothelial cells of the vessels located in the compact portion of the medulla in the left ovary, from the 8th to the 21st day of incubation and after hatching; PNA reactivity was only seen from the 16th day onwards in the endothelial cells of the cortex. During the whole considered period of incubation and after hatching, reactivity with UEAI, LTA and DBA was never detected.

Animals↗

PubMed1999

The oligosaccharidic component of the glycoconjugates in lichen planus, granuloma annulare, seborrheic keratosis and plamoplantar keratoderma: lectin histochemical study.

It is well known that cell surface glycoconjugates play an important role in cell proliferation, adhesion and differentiation. The aim of this investigation was to define the changes of the glycoconjugate saccharidic moieties in the epidermis and derma of patients affected by several skin pathologies such as seborrheic keratosis, lichen planus, granuloma annulare and palmoplantaris keratoderma. Bioptical specimens from skin lesions as well as from normal skin were fixed in Carnoy's fluid and routinely processed. The sections were treated with HRP-lectins (PNA, DBA, SBA, WGA, ConA, LTA and UEAI). Cytochemical controls were performed for specificity of lectin-sugar reaction. Some sections were pre-treated with neuraminidase prior to staining with HRP lectins. In comparison with normal human skin, epidermal lectin binding pattern in the considered diseases showed considerable qualitative and quantitative variations. In general, in all the considered pathologies, a lack and/or a decrease in lectin binding at the epidermal layers was observed; among the various diseases, differences in cellular localisation of the sugar residues were also noted. In such respect, an exception was represented by seborrheic keratosis, where the cells of the basal layer showed PNA reactivity, which was absent in the basal layer of the normal skin. Although seborrheic keratosis and lichen planus have been studied by others authors, our findings are not in total accordance concerning lectin binding; this is probably due to the different fixatives employed. Our findings seem to reveal significant changes in keratinocyte glycoconjugate oligosaccharides in the previously mentioned diseases, providing clues to their pathogenesis.

Concanavalin A↗

PubMed1998

Lectin binding in the human endometrium in early luteal phase following controlled ovarian hyperstimulation.

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 N-acetyl-D-glucosamine and D-mannose respectively, was detected at the level of the lining epithelium.

Adult↗

PubMed1997

Changes in expression of the oligosaccharides in the human fetal skin.

Lectin histochemistry was used to investigate the glycoconjugate saccharidic moieties in the skin of human fetuses ranging in age from the 8th to the 13th week of gestation. For this purpose, seven HRP-conjugated lectins were employed (Con A, WGA, PNA, DBA, SBA, UEAI and LTA). The distribution and changes of the sugar residues of glycoconjugates at the level of the various layers of the fetal epidermis, as well of the underlying mesenchyme were studied. We have shown that UEAI reactivity is a characteristic finding of the cells of the intermediate layer at the 11th and 12th week of gestation. LTA reactivity was detected only at the free border of the peridermal cells from the 10th to the 13th week of gestation. We demonstrated the presence of PNA binding sites at both the basal and peridermal cells from the 8th week of gestation, whereas other authors have stated that the appearance of PNA reactivity coincides with the onset of fetal skin stratification (11th-12th week of gestation). Moreover, some typical features in lectin reactivity at the level of the mesenchymal cells and fibres have been pointed out.

Concanavalin A↗

PubMed1997

Glycoconjugate saccharidic moieties of the exocrine and endocrine pancreas in the chick embryo, newborn and adult.

A battery of horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEAI) was used to study the distribution of glycoconjugate sugar residues in the exocrine and endocrine pancreas of chick embryos, 1-day-old chicks and adult animals. During the period of incubation considered here, the time of appearance and changes in the oligosaccharides were noted in the acinar cells, in the endocrine cells of the "light islets" and in the capillary endothelial cells. In the developing exocrine pancreas, the basolateral surface of the acinar cells reacted with PNA, WGA, LTA and ConA for the entire period of incubation while SBA, WGA, LTA and ConA reactivity was detected in the apical plasma membrane. Zymogen granule membrane reacted with PNA, WGA and LTA from the 12th day onward, while ConA reactivity was detectable from the 7th day onward. Owing to its early appearance, alpha-D-mannose, revealed by ConA lectin, might in some way contribute to the maturation of the zymogen granule. In the 1-day-old chick and in the adult the cellular surface reacted with WGA and ConA. The zymogen granule membrane reacted with PNA, WGA and ConA in the 1-day-old chick. In the adult, WGA and ConA reactivity was observed in the zymogen granule membrane, whereas at this site PNA reactivity was revealed only after neuraminidase digestion. The hypothesis formulated by others that granule membrane lectin reactivity is equal to the apical membrane reactivity, owing to exocytotic processes, is not consistent with our results in the chick embryos, the 1-day-old chick and the adults. The surface and the granules of the islet beta cells in different periods of incubation reacted with WGA, SBA and, after neuraminidase treatment, with PNA. The same reactivity was seen also in 1-day-old chick while in the adult the granules of the beta cells also reacted with ConA. These findings show the achievement of an almost adult-like state of glycosylation of the glycoconjugates in the beta cells at an early stages of development.

Aging↗

PubMed1996

Aging of the human endometrium: peri-implantation phase endometrium does not show any age-dependent variation in lectin binding.

OBJECTIVE: To evaluate if the peri-implantation endometrium shows age variations in lectin patterns, which suggest possible age variations in embryo-maternal recognition. STUDY DESIGN: Peri-implantation endometria of younger ( < 30 years of age: n = 13) and older ( > 40 years of age: n = 17) normally menstruating women was studied. Endometrial specimens were routinely fixed in buffered formaline and embedded in paraffin. Sections (5 microns) were studied using seven lectins: DBA (Dolicus biflorus, binding specificity alpha-D-GalNAc), PNA (Arachis hypogea, binding specificity D-Gal (beta 1 --> 3)-D-GalNAc), SBA (Glycine max binding specificity alpha/beta-D-GalNAc > D-Gal), WGA (Triticum vulgare binding specificity (alpha-D-GlcNAc)n and sialic acid), ConA (Canavalia ensiformis binding specificity alpha-D-Man > alpha-D-Glc), LTA (Lotus tetragonolobus binding specificity alpha-L-fucose) and UEA 1 (Ulex europaeus binding specificity alpha-L-fucose). RESULTS: No significant differences were found in the glycoconjugates sugar residue content and distribution between the endometria of women < 30 years of age and those of women > 40. CONCLUSIONS: Our results suggest that human endometrium does not age, at least while cyclic hormonal stimulation and menstruation are present.

Adult↗

PubMed1996

Sugar residues content and distribution in atrophic and hyperplastic postmenopausal human endometrium: lectin histochemistry.

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 alpha-L-fucosyl residues which bind via alpha (1-6) linkage to penultimate glucosaminyl residues and/or difucosylated oligosaccharides was demonstrated for the first time.

Aged↗

PubMed1995

The value of lymph node dissection in hereditary medullary thyroid carcinoma: a retrospective, European, multicentre study.

Clinical data of 139 patients with hereditary medullary thyroid carcinoma (HMTC) from nine european centres surgically treated from 1980 to 1991 were reviewed retrospectively to analyse the value of systematic versus selective lymphadenectomy (LA). Biochemical cure rate was significantly higher in patients who underwent LA compared to patients who did not. In nodal-positive HMTC, systematic LA compared to selective LA improved biochemical cure in small but not large tumours. In nodal-negative HMTC, systematic LA compared to selective LA could not improve biochemical cure in either small or large primary tumours. To prevent local recurrences with the risk of increased surgical and tumour-related morbidity, systematic LA should be performed in all HMTC patients regardless of the primary tumour stage. However, an improvement of biochemical cure by systematic LA seems to be possible only in nodal-positive small primary tumours without distant metastases.

Adult↗

PubMed1995

Lectin histochemical study of glycoconjugates in the chick embryo proventriculus.

A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties of the lining and glandular epithelium of the chick embryo proventriculus from day 7 to hatching. The sugar residues D-galactose-(beta 1-->3)-N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, alpha/beta-N-acetyl-D-galactosamine and alpha-D-mannose were present at the lining epithelium of the proventriculus from the 7th day onwards; alpha-D-fucosyl residues were never detected. The same sugar residues were detected in the cells of the deep glands from the 7th day; alpha-L-fucose appeared later. The sugar residues appeared in the cells of the superficial glands at different times during the development of the proventriculus. In comparison to that of the deep glands, the secretion of the superficial glands was characterized, by the absence of N-acetylgalactosamine and alpha-D-mannose. From day 20 onwards, the composition of the mucus released by the two types of glands was identical from a qualitative point of view. The histological and histochemical results showed that the superficial glands are well defined morphological structures and not "an artefact of contraction", as claimed by other authors.

Animals↗

PubMed1994

Identification of sugar residues in secretory glycoconjugates of the lining and glandular epithelium of the chick embryo gizzard using lectin histochemistry.

Using seven horseradish peroxidase-conjugated lectins we studied the distribution of glycoconjugate sugar residues in the lining and glandular epithelium of the gizzard in chick embryos from day 7 to 21 of incubation. At the outer layer of the lining epithelium all investigated sugar residues were present from day 7 onwards, except alpha-L-fucose, which was detected later. From day 9 some cells, which contained granules characterised by D-galactose-(beta 1--->3)-N-acetyl-D-galactosamine and N-acetyl-D-glucosamine, were observed in the inner part of the lining epithelium. Afterwards, although in different time periods, all investigated oligosaccharides were detected in intercellular spaces filled with mucous material. At first, the cells of the anlage of the tubular glands appeared to be characterised by D-glucosamine and alpha-D-mannose only. Afterwards, all the investigated sugar residues were detected. At hatching, the luminal glandular secretion showed all investigated sugar residues, except alpha-L-fucose, which was typical for the early formation of the tubular glands. Our data suggest that during the development of the gizzard three time periods of mucous release can be distinguished.

Animals↗

PubMed1994

The nasal respiratory epithelium in the human fetus: lectin histochemistry.

Lectin binding histochemistry was used to investigate the glycoconjugate saccharidic moieties in the respiratory epithelium of human fetuses ranging in age from the 8th to the 12th week of gestation. The distribution and changes in the sugar residues of the glycoconjugates at the level of the basal cells, the bathyprismatic cells and the bathyprismatic ciliated cells are reported. PNA and SBA allowed the identification of some 'elongated cells', which were characterized by lectin-reactive supranuclear granules. These epithelial cells, which have not previously been identified using conventional histochemical methods, might be the precursors of secretory cells.

Embryonic and Fetal Development↗

PubMed1994

Histochemical study of human nasopharyngeal epithelium by horseradish peroxidase conjugated lectins.

This study proposes a simple method for assessing whether non-respiratory epithelia of the nasopharynx (i.e. cuboidal, squamous) represent a modified differentiation from the normal pseudo-stratified lining, or whether they possess common characteristics suggesting they are just in a different morphological stage. Peroxidase-labelled lectins were used, since they detect sugar residues of membrane glycoconjugates which play an important role in cell differentiation. Biopsies were taken from healthy controls and from patients affected by upper airway inflammation of varying degree and duration. While pseudostratified and cuboidal epithelia possess similar histochemical characteristics, squamous epithelium has a different behaviour; in particular it is the only type to show intense reactivity to Lotus tetragonolobus lectin (LTA). This would seem to indicate that squamous epithelium is in a different state of differentiation, possibly suggesting dysplasia. Lectins may be valuable both in morphological studies and in the clinical evaluation of airway epithelia.

Adolescent↗