Biomedical subjects

P Ceccarelli

Publications and source records attributed to P Ceccarelli.

At least 37 records · Page 2Linked to original sources

PubMed1997

Basic and lectin histochemical characterization of bovine gustatory (von Ebner's) glands.

The Bovine tongue possesses numerous circumvallate papillae (8-16 each side). The troughs around the papillae are the openings of the ducts of the gustatory (von Ebner's) glands. In this study, we have characterized in situ the glycosidic composition of the secretion of bovine gustatory glands using traditional histochemical methods and lectin histochemistry with and without prior neuraminidase (sialidase) digestion. The lectin-horseradish peroxidase conjugates employed were: PNA, DBA, SBA, WGA, LTA, UEA I and ConA. Acinar cells show a diffuse positivity towards PAS and Alcian blue at pH 2.5 and the most intense and homogeneous lectin staining was obtained with PNA. This indicates that bovine gustatory glands secrete glycoproteins with 1,2-glycol containing hexoses and carboxyl-rich glycoconjugates and that galactosyl (beta 1-->3) Nacetylgalactosamine is the most frequent sugar residue present in these glycoproteins. Results were compared with data reported in the literature on the same glands of other species.

Animals↗

PubMed1997

Ultrastructural study on the stomach of Tilapia spp (Teleostei).

An ultrastructural study has been made of gastric mucosa of a teleostean fish, Tilapia spp. The cytological features of the surface mucous cells, mucous neck cells, glandular cells and endocrine cells are described. The surface mucous cells, identified by their superficial localization, are characterized by apical granules. The mucous neck cells are distinguished by the appearance of their mucous granules and their localization between surface mucous cells and glandular cells. The gastric glands contain only one form of cell whose fine structure is similar to cells that secrete hydrochloric acid. Physiological implications of some ultrastructural features are also discussed.

Animals↗

PubMed1997

Isolated agenesis of the gallbladder. An intraoperative problem.

Agenesis of the gallbladder and cystic duct is a rare congenital malformation. In 40-70% of cases this anomaly is associated with other gastrointestinal, skeletal, cardiovascular and genitourinary malformations. Lithiasis of the common bile duct is present in 25-50% of cases. In the majority of cases patients are asymptomatic or have symptoms compatible with a biliary disorder. A preoperative diagnosis is extremely difficult and the absence of the gallbladder is often an intraoperative finding. The authors report a case of isolated agenesis of the gallbladder. The relative embryology, development, diagnostic pitfalls, intraoperative behaviour and therapeutic strategies are discussed.

Adult↗

PubMed1996

The presence of granular excretory ducts in the rabbit zygomatic gland.

The proximal and interlobular ducts of rabbit zygomatic glands show a particular morphological feature consisting of numerous secretory granules localized in the apical cytoplasm of the cells. It is suggested that there is a similarity between these ducts and the granular ducts of submandibular glands in rodents.

Animals↗

PubMed1995

A lectin histochemical study of the zygomatic salivary gland of adult dogs.

Seven lectins (PNA, DBA, SBA, UEA I, LTA, WGA and ConA), conjugated with horseradish peroxidase, were used to characterize the glycosidic residues in the zygomatic gland of adult dogs. In some cases (PNA and DBA), lectin staining was preceded by neuraminidase digestion. The acinar and tubular cells produced glycoconjugates with different sugar residues, presenting binding sits for all of the lectins used. The apical surfaces of the cells lining the intra- and interlobular ducts were also stained by all the lectins. In contrast, the demilunar cells only reacted with the Neu-PNA sequence and Con A.

Animals↗

PubMed1995

Sialic acids in the chicken anterior lingual glands detected by lectins combined with enzymatic degradation and oxidizing agents.

The chicken anterior lingual glands contain a large amount of sialoglycoconjugates. This study is aimed at discriminating between them, on the basis of the degree of acetylation and the acceptor sugars, by means of lectins combined with neuraminidase digestion and treatment with oxidizing and deacetylating agents. In the anteromedial part of lingual glands, only low concentrations of periodate-labile sialic acid having alpha 2-3,6-galactose and alpha 2-6-N-acetylgalactosamine acceptor sugars were present. Mostly, C7 and/or C8 acetylated sialic acids occurred, while C9 acetylated sialic acid linked alpha 2-3-galactose and alpha 2-6-N-acetylgalactosamine were restricted to some cells. In the anterolateral part, sialic acid linked alpha 2-6-N-acetylgalactosamine was not acetylated, while sialoderivatives alpha 2-3 linked to galactose were mainly C9 acetylated.

Acetylation↗

PubMed1995

Ultrastructure of bovine von Ebner's salivary glands.

Bovine von Ebner's glands were studied by electron microscopy. The gland consists of tubulo-alveolar adenomeres which open into an abbreviated duct system. The cells of the secretory acini show many morphological features typical of serous cells and contain numerous granules with a complex substructure. Short intercalated ducts connect the acini with excretory ducts which are lined with bistratified epithelium. The striated ducts are absent. The von Ebner's gland morphology was compared with that of the same gland in other species of mammals and with the ultrastructure of the major bovine salivary glands.

Animals↗

PubMed1995

Serotonin-containing cells in the horse gastrointestinal tract.

The presence and distribution of serotonin-containing cells in the gastroenteric tract of horses have been investigated. The enterochromaffin (EC) cells have been identified using immunostaining procedures at both light and electron microscopic level. The EC cells were very numerous in the pyloric gland region, were only few in the duodenum but were absolutely lacking from the more distal portions of the intestine.

Animals↗

PubMed1995

A lectin histochemical study of gustatory (von Ebner's) glands of the horse tongue.

In the present work, gustatory glands (von Ebner's glands) of the horse tongue were examined by means of five peroxidase-conjugated lectins (PNA, DBA, SBA, UEA I, WGA), with and without prior sialidase digestion, in order to investigate the presence and distribution of carbohydrate residues in secretory cells and duct cells. The most intense staining of secretory cells was observed with PNA after pre-treatment with neuraminidase. This indicates that the terminal trisaccharide sequence sialic acid- (alpha 2-->3, 6) galactosyl (beta 1-->3) N-acetylgalactosamine is the most frequent oligosaccharide chain present in glycoproteins secreted by horse gustatory glands. Secretory cells also contained oligosaccharides with terminal alpha-N-acetylgalactosamine and N-acetylglucosamine, whereas fucose was found in only a few glandular cells. The apical cytoplasm of duct lining cells reacted with all the lectins except WGA.

Animals↗

PubMed1995

The endocrine cells in the gastro-enteric tract of adult fallow deer (Dama dama L.).

Endocrine cells were detected in the gastro-enteric tract of the fallow deer by means of immunohistochemical procedures, using antibodies against serotonin, somatostatin, gastrin, glucagon and cholecystokinin. The number of cells positive for each antiserum in each region was evaluated. Serotonin-containing enterochromaffin (Ec) cells were present in every region investigated and were most numerous in the proximal duodenum. Cells positive for somatostatin were present in all the regions studied, with the exception of the colon, and were especially numerous in the proper gastric-gland region. Cells that were stained by the anti-gastrin antibody were very numerous in the pyloric-gland region but only rare in the duodenum. Glucagon-immunoreactive cells were only detected in the large intestine and their frequency was always less than 10/0.5 mm2. Cholecystokinin-containing cells were scarce and restricted to the pyloric-gland region and duodenum.

Animals↗

PubMed1994

Localization of glycoconjugates in dog parotid gland by lectin histochemistry.

Parotid glands from adult dogs were stained with a battery of seven horseradish peroxidase-conjugated lectins (PNA, UEA, LTA, DBA, SBA, WGA and ConA). In some cases (PNA and DBA) neuraminidase digestion was followed by lectin staining. Acinar cells contained conspicuous quantities of oligosaccharides with terminal sialic acid radicals. Galactosil-(beta 1-->3) N-acetylgalactosamine was the most abundant penultimate sugar linked to N-acetylneuraminic acid. Sialylated components having the terminal dimer sialic acid-N-acetylgalactosamine were found in the acinar cells. Secretory cells presented a heterogeneous distribution of glycoconjugates with terminal fucose and beta-N-acetylgalactosamine. Fucose, N-acetylglucosamine and alpha-N-acetylgalactosamine were present on the apical cytoplasm and surface of the striated and interlobular duct cells. This glycosidic composition was unaffected by extensive selective breeding. The role of abundant amounts of sialic acid radicals in the oral mucosa was considered.

Animals↗

PubMed1994

Glycoconjugates in the mandibular salivary gland of adult dogs revealed by lectin histochemistry.

The glycosidic residues in the mandibular glands of five adult dogs were studied by using seven different lectin-horseradish peroxidase conjugates. In some cases a treatment with sialidase preceded the lectin staining. The mucous acinar cells contained oligosaccharides with alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas the demilunar cells contained glycoconjugates rich in sialic acid linked to the penultimate disaccharide galactosyl-(beta 1-->3) N-acetylgalactosamine.

Animals↗

PubMed1993

Basic and lectin histochemistry for studying glycoconjugates in the lingual salivary glands of the Japanese quail (Coturnix coturnix japonica).

Traditional non-lectin staining methods and lectin histochemistry combined with specific exoglycosidase digestion were used to investigate the histological structure of these glands and to visualize the occurrence and composition of salivary glycoconjugates. The quail lingual glands comprise the anterior lingual gland, with rostral and caudal portions that differ in morphology and histochemical staining, and the posterior lingual gland devoid of regional differences. Carbohydrate histochemistry further differentiated the secretory structures by revealing a heterogeneous cell population of tubules within the rostral and caudal portions of the anterior gland, and a rather homogeneous staining of the tubuloalveolar elements in the rostral portion of the anterior lingual gland and in the posterior gland. Tubuloalveolar secretory cells mainly produced sulphate-containing molecules. In addition, sialoglycoconjugates were present in both anterior and posterior lingual glands, whereas fucoglycoconjugates were visualized only in the anterior gland.

Acetylgalactosamine↗

PubMed1993

Lectin histochemical study of bovine lingual glands.

Bovine lingual glands consist of mucous acini capped by demilunes. Information on the chemical structure of their secretory glycoconjugates was obtained by means of a battery of peroxidase-conjugated lectins with affinity for specific terminal sugars. Sialidase procedures followed by lectin staining were also used to visualize the sugar sequences. Stored secretions in mucous acinar cells contained fucose, N-acetylglucosamine, alpha and beta-N-acetylgalactosamine as terminal sugar residues and beta-galactose as penultimate sugar in a heterogeneous distribution. Demilunar cells failed to react with any of the lectins examined except that of Dolichos biflorus.

Acetylgalactosamine↗

PubMed1993

Lectin histochemistry of glycoconjugates in horse salivary glands.

The glycoconjugate content of major horse salivary glands was investigated by means of horseradish peroxidase-conjugated lectins. Qualitative differences were observed in the terminal sugar residues of secretory glycoproteins and glycoconjugates linked to the apical surface of excretory duct epithelial cells. Mucous acinar cells in mandibular and sublingual glands contained oligosaccharides with D-galactose, alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas mandibular, sublingual and parotid serous cells contained only oligosaccharides with terminal alpha- and beta-N-acetylgalactosamine residues. The apical portion of striated and interlobular duct lining cells of mandibular and sublingual glands stained for alpha- and beta-N-acetylgalactosamine and for N-acetylglucosamine. In parotid gland the cytoplasm of intercalated duct cells and the apical surface of striated duct epithelial cells stained for alpha-N-acetylgalactosamine.

Animals↗

PubMed1993

Chemical and electron microscopic studies of cattle (Bos taurus) with four types of phenotypic pigmentation.

The biological behavior of the pigmentary phenotypes of four breeds of cattle has been analysed: the black pigmentation of Holstein Friesian; the red pigmentation of Limousin; the dilution in Charolais; and the postnatal disappearance of red pigmentation in Chianina. The analytic techniques included the characterization of melanins by high-performance liquid chromatography, the examination of follicular melanocytes by light microscopy, and the examination of melanosomes by electron microscopy. The black phenotype was very strongly eumelanogenic. The red phenotype in Limousin is polymorphic: individual follicular melanocytes contain both mature eumelanosomes and pheomelanosomes. Charolais and Chianina cattle exhibited a dramatic reduction in melanogenic activity, which was characterized by the almost exclusive presence of prephaoemelanosomes in Charolais and of immature premelanosomes in Chianina. In the dilute Charolais phenotype, the density of distribution of follicular melanocytes also seemed to be reduced. The genes that are responsible for these four phenotypes seem to act on the maturation, differentiation, and density of distribution of the melanosomes.

Alleles↗

PubMed1992

S-100 protein binds to annexin II and p11, the heavy and light chains of calpactin I.

S-100 protein, a dimeric, Ca(2+)-binding protein of the EF-hand type, interacts with annexin II (p36, the heavy chain of the cytoskeletal protein complex, calpactin I), with p11 (the light and regulatory chain of calpactin I) and with the hetero-tetramer annexin II2-p11(2) (calpactin I) in a Ca(2+)-regulated way, but not with annexins I, V and VI. The interaction of S-100 protein with the above proteins was investigated by fluorescence spectroscopy using acrylodan-S-100 protein and acrylodan-annexin II and by cross-linking experiments using the bifunctional cross-linker disuccinimidyl suberate (DSS). S-100 protein binds with the highest affinity to annexin II (Kd approx. 0.4 microM) and with the lowest affinity to calpactin I (Kd approx. 10 microM), with a constant stoichiometry of about 2 mol of protein/S-100 dimer. Thus, S-100 protein could substitute for p11 in regulating the activities of annexin II in cells which do not express p11 and/or act synergistically with p11 in cells expressing both p11 and S-100. The binding of S-100 protein to p11 could reflect the natural tendency of S-100 subunits and p11 to dimerize. Chimeric p11-S-100 alpha and p11-S-100-beta proteins could therefore form in a Ca(2+)-regulated way. The interaction of S-100 protein with calpactin I appears of doubtful physiological importance, because of the low binding affinity, of the small extent of fluorescence changes induced by calpactin I in acrylodan-S-100 protein and of lack of DSS-induced complex formation between the two protein species.

2-Naphthylamine↗

PubMed1992

Novel isoforms of CaBP 33/37 (annexin V) from mammalian brain: structural and phosphorylation differences that suggest distinct biological roles.

Two calcium-dependent phospholipid- and membrane-binding proteins have been purified from bovine brain. These are termed CaBP33 and CaBP37. Complete sequence analysis has revealed that these two proteins are isoforms of annexin V. Despite an apparent difference of 4 kDa between the two proteins on SDS-PAGE, only two amino-acid substitutions were found. These are, in CaBP33, Ser-36 and Lys-125 and in CaBP37, Thr-36 and Glu-125. This corresponds to a mass difference of 15 Da. This was confirmed by electrospray mass spectrometric analysis. Both isoforms can be phosphorylated substoichiometrically in vitro by protein kinase C at residue Thr-22.

Amino Acid Sequence↗