PubMed Health⌕ Search

Biomedical subjects

D Balas

Publications and source records attributed to D Balas.

At least 55 records · Page 3Linked to original sources
PubMed1982

[Immunohistochemical localization of pituitary peptides in the rat pyloric antrum mucosa].

Several peptides normally produced in the anterior pituitary lobe were searched in rat antral mucosa by immunocytochemistry. Peptides derived from pro-opiomelanocortin were tested: some endocrine cells were immunoreactive with ACTH 17-39 antiserum, and only a few elements were stained with ACTH 1-24 and beta LPH antisera. No immunoreactive cells were observed using alpha MSH, beta MSH and beta endorphine antisera. Using an antiserum against beta endorphin, a few cells and nerve fibres were immunostained. The other pituitary hormones were also tested: numerous antral cells contained immunoreactive GH, and some cells immunoreactive PRL or compounds chemically related to these hormones. No cells were stained with antisera directed against glycoproteic hormones. This work showed that several peptides previously localized in the pituitary gland were found in the antral mucosa. Further studies are needed to identify the cell types containing these peptides and to determine their origin.

Adrenocorticotropic Hormone↗
PubMed1981

Experimental study of laser photocoagulation in the treatment of bleeding canine gastric ulcers.

We report experimental results obtained by laser photocoagulation on hemorrhagic lesions induced in dogs. The aims of this study were 1) to evaluate the real efficiency of the YAG laser to ensure hemostasis of briskly bleeding lesions; 2) to determine the minimum energy density necessary to ensure hemostasis; 3) to assess the damage depth inside the gastric wall after photocoagulation; 4) to compare reepithelialization of treated ulcers with that of control ulcers; 5) to evaluate the safety margin for the clinical use of the YAG laser.

Animals↗
PubMed1981

Effect of pancreatic duct ligation on the hamster intestinal mucosa. Variation of several hydrolases.

Hamster intestinal hydrolase activities were studied after pancreatic duct ligation for periods of 5, 7, 10, 15 and 30 days. From the 7th to the 10th day, maltase and sucrase were significantly increased in the jejunoileum. Higher levels were observed on day 7 in the duodenum for all the brush-border enzyme activities (maltase, sucrase, aminopeptidase, alkaline phosphatase). Intestinal lysozyme significantly increased from the 5th to the 15th day with a maximal level at the 7th day. The increased levels of brush-border enzymes observed here are not in accordance with our description of villous atrophy after pancreatic duct ligation in the hamster. On the other hand, the important increase in lysozyme activity is in good agreement with hypertrophy and hyperplasia of the Paneth cells which we observed during our morphological study. The morphological and biochemical findings on hamster small intestine confirm the effects of exocrine pancreatic secretion both on differentiation and on enzymatic levels of the mucosa. Besides, this experiment agrees with the direct desorbing action of the pancreatic juice on the brush border and suggests another hypothetical mechanism, still worth being investigated, to explain increased brush-border activities in the duodenum and increased levels of lysozyme in the jejunoileum.

Alkaline Phosphatase↗
PubMed1981

Long term effects of H2-receptor antagonists (cimetidine and ranitidine) on the human gastric and duodenal mucosa.

Cytological effects of two H2-receptor antagonists on the gastric and duodenal mucosa were studied during therapy of active duodenal ulcer (D.U.) in man. After endoscopic diagnosis (day 0), subjects were treated with cimetidine or ranitidine and re-examined on day 30. Only subjects with healed D.U. on day 30 were retained in this study. Gastric, pyloric and duodenal endoscopic biopsies were taken and treated for further morphometrical analysis both by light and electron microscopy. The use of the immunoperoxidase technique allowed evaluation of G and D cell populations. Kinetic parameters in proliferative zones were measured after in vitro incubation of biopsies with 3H-thymidine. No differences could be seen between the two H2-receptor antagonists. Increase of tubulovesicles and decrease of canaliculi in parietal cells are closely related to the inhibitory effect of these drugs on acid secretion. However secretory capacities of parietal cells are preserved since the whole membrane (tubulovesicle + canaliculi surface) remained constant. The collapsed aspect of the tubulovesicles on day 30 and the presence of connections between the tubulovesicle membrane, with both vesicle and canaliculi membrane, could support the theory of osmotic membrane expansion during parietal cell acid secretion. H2-receptor antagonists have been shown to be trophic in duodenal mucosa: both villi and microvilli area are increased. Confirming these findings, the proliferative compartment in the intestinal crypts was shown to be enlarged. No variation of G cell number could be seen in the antral mucosa; clear intracytoplasmic granules were increased in D.U. on day 0 but were not further modified on day 30. Somatostatin labelling index decreased. These last findings associated with the lack of G cell variations, suggest the presence of a possible paracrine modulation in the gastric and duodenal mucosa.

Biopsy↗
PubMed1980

Effects of pancreatic duct ligation on the hamster intestinal mucosa. Histological findings.

After pancreatic duct ligation good correlations were observed between degenerative signs of the exocrine pancreas and ultrastructural changes of intestinal epithelial cells: hypertrophy of Paneth and goblet cells; hyperplasia of Paneth cells, mucous cells and 'intermediate granular cells' after the 10th day. On the 7th day, the absorbing area of the intestine (villi area and microvilli area) decrease significantly. These cytological changes partially disappear after the 15th day concomitant to a partial regeneration of the exocrine pancreas. These findings suggest correlations between the epithelial cells of the small intestine and exocrine pancreatic secretion. Different possibilities (direct action of the pancreatic juice or indirect mechanisms) are discussed and proposed to explain the morphological variations of the intestinal mucosa after pancreatic duct ligation.

Animals↗
PubMed1979

A cyto-physiological study of the G-cell secretory cycle in the antrum mucosa of the hamster and of the rat.

The secretory cycle of the antral G cell in the golden hamster and in the Wistar rat has been investigated, using classical techniques of optical and electron microscopy associated with special methods (such as goniometry, densitometry, immunohistology, morphometry) and with radioimmunoassay for gastrin. This paper confirms the secretory cycle of the G cell after refeeding. It clarifies the nature of granule polymorphism and suggests a particular mechanism of emiocytosis with sequential granule fusion. Furthermore, our investigations show some dissociations between the G cell, the parietal cycle, and the seric immunoreactive gastrin in the late phase of the secretory cycle (2 to 6 h after refeeding).

Animals↗
PubMed1979

Comparative effects of CCK-PZ on certain intestinal hydrolases in the mucosa and in the luminal content of the hamster jejuno-ileum.

After isolation of the hamster small intestine, the effects of a continuous infusion of cholecystokinin-pancreozymin (CCK-PZ) are studied. Several enzymic activities are measured in the intestinal lumen and compared with the level found in the intestinal homogenate. During CCK-PZ infusion we observed a direct stimulation of Paneth cells associated with an increase of lysozyme activity. Furthermore this work confirms the stimulating effect of CCK-PZ on alkaline phosphatase and amino-peptidase. Maltase and sucrase levels were unaffected. The liberation of the hydrolase of the brush border in the intestinal lumen is negligible and cannot be considered as a true secretion. Only granule content of Paneth cells is actually secreted. However, biochemical data, corroborated by morphological results, suggest that Paneth cell secretion could in part be absorbed on the outer surface of the brush border.

Alkaline Phosphatase↗
PubMed1977

[Vogt-Koyanagi-Harada disease. About two observations (author's transl)].

After a reminder of clinical symptoms and development of the V.-K.-H. disease, some histological and clinical observations are related. The clinical observations are very characteristic of the V.-K.-H. disease. There are only two notable points: in both observations, a very low lymphocytic reaction to phytohemaglutinin and in the first observation, the presence of an anemia with parallel evolution to the uveitis. The histological examination of the depigmented area shows an infiltrate as described by Perrot, around the involved area in vitiligo. Ultrastructural study identifies 250 angströms wide particles that appear to be particles of alpha-glycogene, well developed amyelinic endings, and lastly, lymphocytoid cells closely joined with dendritic cells having internal granulations. These aspects have already been found in the iris by the Japanese authors, and they evoked an immunological mechanism.

Adult↗