1,721,080 research outputs found
Parillo (Francesco) - " La cooperazione economica internazionale e i paesi in via di sviluppo " Giornale degli economisti e annali di economia.
No full textClair Pierre. Parillo (Francesco) - " La cooperazione economica internazionale e i paesi in via di sviluppo " Giornale degli economisti e annali di economia.. In: Revue économique, volume 18, n°4, 1967. p. 695
Glycocomposition of the apocrine interdigital gland secretions in the fallow deer (Dama dama)
Get PDFThe secretions of the tubular interdigital glands were investigated by conventional (Periodic-Acid Schiff,
Alcian-Blue at different pH, Low Iron Diamine and High Iron Diamine) and lectin (Con-A, UEA-I, LTA,
WGA, GSA-II, GSA-IB4, SBA, PNA, ECA, DBA, MAL-II and SNA) histochemical methods in adult males
and females of different age of fallow deer during the breeding season. Sialidase digestion and deacetylation
pre-treatment were also employed in conjunction with lectin histochemistry.
The glandular epithelium consisted of a single layer of low columnar cells with typical apical protrusions.
No substantial differences of the above histochemical staining in relation to sex and age were
observed. Conventional histochemical staining revealed that the interdigital glands secreted neutral glycoproteins
whereas acidic glycocomponents did not seem to be present. Lectin histochemical technique
allowed us to disclose a great heterogeneity of glycoproteins with N- and O-linked oligosaccharides containing
alpha-D-Man/alpha-D-Glc, GlcNAc, alpha-Fuc, terminal beta-D-Gal-(1-3)-D-GalNAc, -D-Gal-(1-4)-D-GlcNAc, alpha-Gal
and beta-GalNAc residues. beta-GalNAc and disaccharide beta-D-Gal-(1-3)-D-GalNAc were also found as subterminal
to sialyl moieties. The lack of sexual and age-related differences in the glucidic content of the glandular
secretions seems to indicate that the glycoderivatives may play only an accessory role in the
production of odoriferous signals in fallow deer
Glycohistochemical investigation on canine and feline zonae pellucidae of preantral and antral oocytes
Get PDFGlycoconjugate modifications were analysed in the zona pellucida during development of oocytes in dog and cat using conventional histochemical staining methods with or without previous carbohydrate digestion. A series of lectins combined with desulphation and sialic acid degradation were applied. No differences were observed between dog and cat follicles using conventional histochemical staining methods. In both species, the zona pellucida and follicular fluid/intercellular matrix strongly reacted with PAS and high iron diamine stain (HID) and reacted moderately with low iron diamine stain (LID). Treatment with testicular hyaluronidase, chondroitinase ABC, chondroitinase AC and chondroitinase B treatment diminished HID and LID positivity of follicular fluid and intercellular matrix. Lectins that gave the most intense staining of the zona pellucida of both species were SBA, PNA, RCA-I, GSA-IB4 and WGA, indicating the presence of beta-D-GalNAc, D-Gal and GlcNAc residues. Sulpho- and asulpho-carbohydrates were identified in terminal and/or subterminal positions linked to sialic acid residues. In conclusion, the results indicate that glycosaminoglycans are not present in the zona pellucida of both species. Differences were observed in carbohydrate residues and in their spatial distribution, depending on species and developmental stage of the follicles. The similarity in lectin affinity between ooplasm and zona pellucida of oocytes present in follicles at different stages of development confirm the involvement of oocytes in zona pellucida production
Glycohistochemistry of the zona pellucida of developing oocytes in the rabbit and hare
Get PDFLagomorpha are often used as animal models in reproductive experiments. The aim of the present study was to examine the glycoconjugate modifications occurring mainly in the zona pellucida during oocyte growth in the rabbit and hare, using a battery of lectins combined with sialidase digestion and chemical treatments. This histochemical approach made it possible to identify sulpho- and asulpho-carbohydrates in the terminal and/or subterminal position linked to sialic acid residues. The lectins that stained the zona pellucida of both species most effectively were SBA, PNA and WGA, indicating the presence of beta-D-N-acetylgalactosamine, beta-D-galactosamine and N-acetylglucosamine residues. The differences in the glucidic residue content and in their spatial distribution that depended on the species and stage of follicle development were also detected
Characterization of glycoconjugates in the secretory epithelium of the equine ampulla ductus deferentis
No full textThe present work was undertaken to
determine the glycoconjugates secreted by the
epithelium of the equine ampulla ductus deferentis,
using conventional (PAS, AB pH 2.5, AB pH 1.0) and
lectin histochemical procedures in conjunction with
enzymatic digestion and chemical treatment. The
presence of abundant apical cytoplasmic blebs suggests
that the equine ampulla secretes its products mainly in
an apocrine manner. Glandular cells secrete neutral and
acidic sialylated glycoconjugates as revealed by
conventional histochemical procedures. Lectin
histochemistry helped us to discover the following
histological positive sites: the mucosal cells, the
glandular epithelial cells, the apical cytoplasmic blebs
and the basal cells. The ampullary secretions contained
both glycoproteic material (revealed by Con-A-, LCA-,
GSA-II-, WGA-, RCA-I- positivity) and sialomucins
(evidenced by the reactivity of GSA-II, SBA, PNA and
RCA-I after sialidase digestion) having different
functional roles. The mucosal cells reacted with Con-A,
LCA, and also with sialidase/GSA-II-, SBA-, PNA-, and
RCA-I sequences, contributing to the chemical
heterogeneity of ampullary secretions. DBA lectin was a
specific marker for basal cells.
The results obtained were compared with our
previous findings regarding the differences in the lectin
binding pattern of the plasma-membrane of equine
sperm collected from epididymal cauda and the ampulla
ductis deferentis. Our results support other studies that
indicate that ampullary secretions are involved in
altering the plasma-membrane glycoconjugates of
spermatozoa, contributing to their maturation
Glycohistochemical investigation on canine and feline zonae pellucidae of preantral and antral oocytes
No full textGlycoconjugate modifications were analysed in the zona pellucida during development of oocytes in dog and cat using conventional histochemical staining methods with or without previous carbohydrate digestion. A series of lectins combined with desulphation and sialic acid degradation were applied. No differences were observed between dog and cat follicles using conventional histochemical staining methods. In both species, the zona pellucida and follicular fluid/intercellular matrix strongly reacted with PAS and high iron diamine stain (HID) and reacted moderately with low iron diamine stain (LID). Treatment with testicular hyaluronidase, chondroitinase ABC, chondroitinase AC and chondroitinase B treatment diminished HID and LID positivity of follicular fluid and intercellular matrix. Lectins that gave the most intense staining of the zona pellucida of both species were SBA, PNA, RCA-I, GSA-IB4 and WGA, indicating the presence of beta-D-GalNAc, D-Gal and GlcNAc residues. Sulpho- and asulpho-carbohydrates were identified in terminal and/or subterminal positions linked to sialic acid residues. In conclusion, the results indicate that glycosaminoglycans are not present in the zona pellucida of both species. Differences were observed in carbohydrate residues and in their spatial distribution, depending on species and developmental stage of the follicles. The similarity in lectin affinity between ooplasm and zona pellucida of oocytes present in follicles at different stages of development confirm the involvement of oocytes in zona pellucida production
Complex carbohydrates occurring in the digestive apparatus of the Umbrina cirrosa (L.) fry
No full textThe glycosoaminoglycans in the digestive apparatus of immature fish have important biological functions and are involved in morphofunctional differentiation. The aim of this study was to investigate the glycoconjugate histochemistry in the different parts of the digestive apparatus (oesophagus, stomach, intestine) of Umbrina cirrosa (L.) fry using classical histochemical reactions (periodic acid-Schiff, Alcian blue pH 2.5, Alcian blue/periodic acid-Schiff, high iron diamine, low iron diamine) in conjunction with glycolytic digestions that degrade different classes of glycosoaminoglycans. No differences were observed in the reactivity to conventional histochemical staining of the oesophagus, stomach or intestine among 27-, 34- or 44-day-old fry. In the oesophagus, the mucopolysaccharides contained chondroitin sulphates B and A and/or C, heparan sulphate and chondroitin. In the stomach, only neutral glycoconjugates were revealed, whereas in the intestine there were only chondroitin sulphates. Some differences in the type and content of glycoconjugates were found in Umbrina cirrosa (L.) fry compared to those of adult subjects, probably related to different dietary habits and to changes in the environmental conditions
Immunohistochemical localization and identification of orexin A and orexin B type 2 receptor in the horse gastrointestinal apparatus.
No full textHistochemical characterization of plasma membrane glycoconjugates in ejaculated equine sperm
No full text- …
