RESUMO
OBJECTIVE: To determine the incidence and occupational variation of granulosa cell tumours (GCTs) in Finland, Iceland, Norway and Sweden over a 60-year period, 1953-2012. DESIGN: A longitudinal cohort study. SETTING AND POPULATION: Finland, Iceland, Norway and Sweden and a total of 249 million women over a 60-year period (1953-2012). The NOCCA (Nordic Occupational Cancer Study) included 6.4 million women with 776 incident GCT cases diagnosed until the end of follow up. METHODS: Incidence rates were calculated from the national cancer registries and compared using quasi-Poisson regression models. Occupation-specific standardised incidence ratios (SIRs) were calculated from the Nordic Occupational Cancer (NOCCA) database. MAIN OUTCOME MEASURES: Incidence rates and standardised incidence ratios. RESULTS: The age-adjusted (World Standard) incidence rates remained quite constant: about 0.6-0.8 per 100 000 for most of the study period. The age-specific incidence was highest at 50-64 years of age. There were no occupations with significantly increased risk of GCT. Major changes in the use of oral contraceptives, postmenopausal hormonal therapy, fertility rate and lifestyle in general during the study period and among different occupational categories do not appear to have a marked effect on the incidence of GCT. CONCLUSION: Our findings support the concept of GCT as a primarily sporadic, not exposure-related, cancer. TWEETABLE ABSTRACT: The Nordic incidence rates of GCTs show stability over time and among different occupational categories.
Assuntos
Tumor de Células da Granulosa/epidemiologia , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Neoplasias Ovarianas/epidemiologia , Adulto , Estudos de Coortes , Feminino , Finlândia/epidemiologia , Seguimentos , Humanos , Islândia/epidemiologia , Incidência , Estudos Longitudinais , Pessoa de Meia-Idade , Noruega/epidemiologia , Ocupações , Sistema de Registros , Medição de Risco , Fatores de Risco , Suécia/epidemiologiaRESUMO
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 and/or 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-(beta 1-->3)-N-acetyl-D-galactosamine, beta-N-acetyl-D-galactosamine and alpha-L-fucose 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 alpha-L-fucose and afterwards also by the presence of D-galactose-(beta 1-->3)-N-acetyl-D-galactosamine, D-glucosamine and sialic acid.
Assuntos
Metabolismo dos Carboidratos , Esôfago/metabolismo , Glicoconjugados/metabolismo , Animais , Sequência de Carboidratos , Embrião de Galinha , Epitélio/embriologia , Epitélio/crescimento & desenvolvimento , Epitélio/metabolismo , Esôfago/anatomia & histologia , Esôfago/embriologia , Esôfago/crescimento & desenvolvimento , Glândulas Exócrinas/metabolismo , Hidrólise , Técnicas Imunoenzimáticas , Lectinas , Dados de Sequência Molecular , NeuraminidaseRESUMO
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.
Assuntos
Endométrio/metabolismo , Lectinas/metabolismo , Lectinas de Plantas , Proteínas de Soja , Adulto , Concanavalina A/metabolismo , Endométrio/patologia , Feminino , Fertilização in vitro , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Síndrome de Hiperestimulação Ovariana/induzido quimicamente , Síndrome de Hiperestimulação Ovariana/metabolismo , Ovário , Aglutinina de Amendoim/metabolismo , Aglutininas do Germe de Trigo/metabolismoRESUMO
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.
Assuntos
Granuloma Anular/metabolismo , Ceratodermia Palmar e Plantar/metabolismo , Ceratose Seborreica/metabolismo , Lectinas/metabolismo , Líquen Plano/metabolismo , Oligossacarídeos/metabolismo , Lectinas de Plantas , Concanavalina A/metabolismo , Glicoconjugados/metabolismo , Granuloma Anular/patologia , Humanos , Ceratodermia Palmar e Plantar/patologia , Ceratose Seborreica/patologia , Líquen Plano/patologia , Aglutinina de Amendoim/metabolismo , Aglutininas do Germe de Trigo/metabolismoRESUMO
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.
Assuntos
Carboidratos/análise , Endométrio/patologia , Oligossacarídeos/análise , Pós-Menopausa , Idoso , Atrofia , Feminino , Fucose/análise , Glucosamina , Histocitoquímica , Humanos , Hiperplasia , Lectinas , Pessoa de Meia-IdadeRESUMO
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.
Assuntos
Metabolismo dos Carboidratos , Ciclosporina/farmacologia , Glicoconjugados/metabolismo , Imunossupressores/farmacologia , Timo/citologia , Timo/efeitos dos fármacos , Animais , Atrofia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Histocitoquímica , Peroxidase do Rábano Silvestre , Lectinas , Masculino , Neuraminidase/química , Ratos , Ratos Wistar , Timo/metabolismo , Fixação de TecidosRESUMO
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.
Assuntos
Tubas Uterinas/crescimento & desenvolvimento , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Metabolismo dos Carboidratos , Endométrio/anatomia & histologia , Endométrio/crescimento & desenvolvimento , Tubas Uterinas/anatomia & histologia , Tubas Uterinas/metabolismo , Feminino , Histocitoquímica , Peroxidase do Rábano Silvestre , Humanos , Hidrólise , Lectinas , Pessoa de Meia-Idade , Neuraminidase , Inclusão em Parafina , Pós-Menopausa/fisiologiaRESUMO
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.
Assuntos
Metabolismo dos Carboidratos , Embrião de Galinha/fisiologia , Glicoconjugados/metabolismo , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos/metabolismo , Embrião de Galinha/anatomia & histologia , Embrião de Galinha/metabolismo , Histocitoquímica , Lectinas , Oligossacarídeos/metabolismoRESUMO
The anlage of duodenum, ileum and colon were removed from chick embryos of day 8-21 of incubation and from 1-day-old chicks. A battery of seven different horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, Con A, WGA, LTA and UEAI) was used to study the carbohydrate residues of the glycoconjugates in the goblet cells of the three parts of the intestine. The main results can be summarized as follows: differences in lectin binding were absent in the proximal and distal parts of the duodenum, ileum and colon. Lectin histochemistry showed differences among the three intestinal segments for the time of appearance of the oligosaccharides in the goblet mucus. In the colonic goblet cells of 1-day-old chicks, LTA and UEAI lectins showed two different types of linkage of alpha-L-fucose. This is the first demonstration of UEAI reactive sites in Gallus domesticus.
Assuntos
Carboidratos/análise , Células Caliciformes/química , Lectinas/análise , Animais , Animais Recém-Nascidos , Embrião de Galinha , Galinhas , Colo/química , Colo/embriologia , Colo/ultraestrutura , Duodeno/química , Duodeno/embriologia , Duodeno/ultraestrutura , Células Caliciformes/ultraestrutura , Íleo/química , Íleo/embriologia , Íleo/ultraestrutura , Técnicas ImunoenzimáticasRESUMO
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.
Assuntos
Envelhecimento/metabolismo , Implantação do Embrião/fisiologia , Endométrio/metabolismo , Lectinas/metabolismo , Adulto , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , GravidezRESUMO
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.
Assuntos
Metabolismo dos Carboidratos , Moela das Aves/metabolismo , Glicoconjugados/metabolismo , Lectinas/química , Animais , Sequência de Carboidratos , Carboidratos/análise , Carboidratos/química , Embrião de Galinha , Células Epiteliais , Epitélio/metabolismo , Moela das Aves/embriologia , Glicoconjugados/química , Histocitoquímica , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Lectinas/metabolismo , Dados de Sequência MolecularRESUMO
Tongue anlage were taken in chick embryos from the 7th to the 21st d of incubation and in 3 d old chicken. A battery of 7 different horseradish peroxidase-conjugated lectins (PNA, ConA, DBA, SBA, LTA, WGA, UEA I) was used to study the carbohydrate residues of glycoconjugates at the epithelial cells of the anterior and posterior lingual glands. Some sugar residues, detected at the surface of the epithelial cells in early developmental stages of glandular primordia, seemed to play a role in inducing and regulating the first differentiative steps of the glands. Differences in type, amount, time of appearance and cellular localization between the 2 groups of glands were detected. The group of the anterior lingual glands, adjacent to the entoglossal cartilage (paraentoglossal glands), showed some peculiar histochemical characteristics.
Assuntos
Carboidratos/análise , Língua/embriologia , Animais , Sequência de Carboidratos , Embrião de Galinha , Histocitoquímica , Peroxidase do Rábano Silvestre , Lectinas , Dados de Sequência Molecular , Língua/citologiaRESUMO
Fragments of metanephros were taken from chick embryos and studied from the 7th to the 21st d of incubation. A battery of 7 different horseradish peroxidase-labelled lectins (PNA, ConA, DBA, SBA, LTA, WGA and UEA I) was used to analyse the distribution and changes of carbohydrate moieties in glycoconjugates along the metanephric nephron from the S-shaped body stage onwards. DBA and SBA reacted for a short time at some sites during the considered period of incubation. Provided WGA and ConA reacted with most of the nephric components, the almost ubiquitous presence of N-acetyl-D-glucosamine and alpha-D-mannose was demonstrated. SBA and LTA were found to be good markers of the proximal tubule. On the 12th d of incubation, sialic acid was found in the podocytes, capillary walls, and the connecting and collecting ducts. On the same day, other oligosaccharides were present at the nephric tubular components. The simultaneous presence of sialic acid and other sugar residues may be significant for the identification of the exact stage of incubation at which metanephric activity starts. The possible role of some sugar residues for the regulation of metanephric activity is discussed.
Assuntos
Carboidratos/análise , Glicoconjugados/análise , Rim/embriologia , Lectinas/metabolismo , Animais , Sítios de Ligação , Sequência de Carboidratos , Embrião de Galinha , Glicosilação , Histocitoquímica , Peroxidase do Rábano Silvestre/química , Rim/química , Glomérulos Renais/química , Glomérulos Renais/embriologia , Túbulos Renais/química , Túbulos Renais/embriologia , Microvilosidades/química , Dados de Sequência MolecularRESUMO
A battery of horseradish peroxidase-conjugated lectins (ConA, WGA, PNA, SBA, DBA, UEAI and LTA) was used to study the content and distribution of glycoconjugate sugar residues of the normal human nasal mucosa. Our findings indicate that differences exist between the types of sugar residues found in the secretory product of the mucous goblet-like cells and those found in the mucous glands secretion. The saccharide content of the epithelial basal cells, which has never been previously investigated, is reported. Differences in the content and distribution of glycoconjugate sugar residues were found between human nasal mucosa and that of the other human extrapulmonary tracts.
Assuntos
Carboidratos/análise , Glicoconjugados/análise , Mucosa Nasal/química , Adolescente , Adulto , Sequência de Carboidratos , Criança , Feminino , Histocitoquímica , Peroxidase do Rábano Silvestre , Humanos , Lectinas , Masculino , Dados de Sequência Molecular , Valores de ReferênciaRESUMO
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.
Assuntos
Glicoconjugados/metabolismo , Ilhotas Pancreáticas/metabolismo , Monossacarídeos/metabolismo , Pâncreas/metabolismo , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos , Embrião de Galinha , Ilhotas Pancreáticas/citologia , Pâncreas/citologia , Pâncreas/embriologiaRESUMO
With the aim of clarifying certain morphological aspects of lingual development, chick tongues between the 8th day of incubation and hatching and also during the early postincubation period were investigated by means of the Scanning Electron Microscope. During this time, the tongue anlage underwent some remarkable morphogenetic changes, mostly involving the superficial epithelium but also including the appearance of the lingual glands at the level of the lingual root. With regards to the epithelium, it was possible to observe that in the first days of the incubation period examined, the superficial cells appeared dome-shaped, with microvilli on the apical surface; later they tended to become more flattened, and the microvilli were replaced by a thick net of microplicae. During the final days of incubation, and after hatching desquamative phenomena became evident. At no site of the tongue rudiment were taste buds ever observed, possibly because of the different functional role played by the avian tongue in comparison with that of the mammals.
Assuntos
Língua/embriologia , Fatores Etários , Animais , Embrião de Galinha , Galinhas/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Língua/crescimento & desenvolvimento , Língua/ultraestruturaRESUMO
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.
Assuntos
Oligossacarídeos/metabolismo , Pele/embriologia , Concanavalina A , Epiderme/embriologia , Epiderme/metabolismo , Fixadores , Idade Gestacional , Peroxidase do Rábano Silvestre , Humanos , Lectinas , Mesoderma/metabolismo , Aglutinina de Amendoim , Pele/metabolismoRESUMO
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.
Assuntos
Glicoconjugados/metabolismo , Lectinas , Estômago de Aves/metabolismo , Animais , Sequência de Carboidratos , Embrião de Galinha , Células Epiteliais , Epitélio/embriologia , Epitélio/metabolismo , Histocitoquímica , Dados de Sequência Molecular , Estômago de Aves/citologia , Estômago de Aves/embriologiaRESUMO
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.
Assuntos
Animais Recém-Nascidos/metabolismo , Embrião de Galinha/metabolismo , Galinhas/metabolismo , Lectinas/metabolismo , Ovário/embriologia , Ovário/metabolismo , Animais , Embrião de Galinha/fisiologia , Feminino , Histocitoquímica , Ovário/citologia , Distribuição TecidualRESUMO
The authors have investigated the morphological aspects of the wall components of the developing colon in the chick embryo (Gallus domesticus) from the 7th to th 15th day of incubation. Particular attention has been given to the lumen recanalization, phenomenon which occurs also in other animal species. The most significant results can be summarized as follows: 1) the lumen is recanalized at the 7th day only at the proximal part of the colon (Fig. 1, Tav. 1), while at the distal tract it is still completely filled by an epithelial plug (Fig. 2, Tav. 1). Therefore the recanalization of the lumen takes place cranio-caudad. 2) At the 8th day the process of recanalization of the lumen shows, in the distal part of the colon, well defined modalities. Radially oriented intraepithelial spaces within the epithelium filling the lumen join other semilunar intercellular spaces, which are placed near the central part of the occluded lumen (Fig. 3). By the junction of a couple of radially oriented spaces with one semilunar space, an U-shaped intercellular space derives, which delimits an incoming epithelial fold (Tav. 3). Such a phenomenon is continued also during the 9th and 10th day of incubation (Fig. 6, Tav. 2). 3) At the 11th day the colonic lumen is completely open and, in its distal part, the appearance of the primordial previllous ridges can be observed (Fig. 7). In the proximal tract the previllous ridges develop one day later (Fig. 8). 4) At the 13th day, in the distal part of the colon, the first appearance of crypts occurs (Fig. 10). So, while the process of recanalization of the lumen is cranio-caudad, the formation of previllous ridges and crypts proceeds caudo-cranially. 5) From the 11th day onwards the lamina propria is actively involved in the process of formation of the previllous ridges. Only at the 14th day, in the distal part of the colon anlage, the appearance of the muscularis mucosae is observed (Fig. 11). 6) The muscle layer and the subserous stratum do not show appreciable morphological changes in the course the considered period of incubation.