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C Bordi

Publications and source records attributed to C Bordi.

At least 109 records · Page 6Linked to original sources
PubMed1991

Ultrastructural morphometry of gastric endocrine cells before and after omeprazole. A study in the oxyntic mucosa of duodenal ulcer patients.

Long-term toxicological experiments with inhibitors of acid secretion were found to induce hyperplasia and eventually carcinoid tumors of the enterochromaffin-like cells of the oxyntic mucosa. To evaluate the effects of 6 months' treatment with omeprazole in humans, the oxyntic endocrine cells were morphometrically investigated at the ultrastructural level in five patients with active duodenal ulcer. No omeprazole-induced changes were found in the volume density of the total endocrine cell population and specific cell types (including the enterochromaffin-like cell) as well as in the other cytological parameters investigated (number of cell profiles per unit area, mean cross-sectional area of cell profiles, nuclear-cytoplasmic ratio, and density of cytoplasmic secretory granules). Both pretreatment and post-treatment values in our patients with duodenal ulcer significantly differed from those of a previous investigation of healthy volunteers with regard to the volume density of enterochromaffin-like cells and non-granulated cells, which increased, and of D cells, which markedly decreased. The latter result may provide a cellular basis for impairment in the paracrine release of fundic somatostatin in peptic ulcer disease. Finally, morphometric data on endocrine cell volume density provided by electron microscopy were found to correlate with those obtained in the same patients using light microscopy techniques (Grimelius silver impregnation and chromogranin A immunostaining). It is concluded that 6 months' treatment with pharmacological doses of omeprazole is devoid of appreciable trophic effect on endocrine cells of human oxyntic mucosa.

Adult↗
PubMed1990

Immunohistochemical localization of factor X-like antigen in pancreatic islets and their tumours.

The authors have investigated by immunohistochemistry the distribution of factor X-like antigen in normal pancreatic islets and in a series of 46 pancreatic endocrine tumours. It was found that both glucagon-producing (A) cells and pancreatic polypeptide-producing (PP) cells are immunoreactive for the antigen. Benign glucagonomas and PP-omas presented the highest concentrations of immunoreactive material whose intracellular distribution was consistent with localization within cell secretory granules. Some benign insulinomas also presented factor X immunostaining in spite of the absence of the antigen in normal insulin-producing B cells. Although malignant tumours usually exhibited very low or no immunostaining, two of three malignant glucagonomas showed scattered, intensely immunoreactive cells. The factor X-like antigen identified in this study was found to differ from chromogranin A and B. The possible implications of the present findings for coagulative disorders associated with glucagonomas or diabetes are discussed.

Adenoma, Islet Cell↗
PubMed1990

Quantitative ultrastructure of endocrine cells of oxyntic mucosa in Zollinger-Ellison syndrome. Correspondence with light microscopic findings.

The endocrine cells of the oxyntic mucosa of five patients with longstanding Zollinger-Ellison syndrome were quantitatively investigated with electron microscopy and two light microscopic methods (Grimelius and immunostaining for chromogranin A). Ultrastructurally, the volume density of endocrine cells was 3.2% +/- 1.1% of the mucosal epithelial component, a 168% increase (P less than 0.001) over the value found in normal subjects. Of the six endocrine cell types of human oxyntic mucosa, only enterochromaffinlike cells increased in cell density (65% +/- 15% of the total endocrine cell mass), size, and number of cell profiles per unit area. The enterochromaffinlike cells also underwent morphological changes of secretory granules with a decrease in vacuolated forms, increase in elongated profiles, and appearance of granules with a punctate structure of the core. The latter variety of granules was previously observed only in carcinoid tumors of the oxyntic mucosa and is possibly related to the enterochromaffinlike cell hyperplasia-neoplasia sequence seen in hypergastrinemic patients. A positive relationship was found between endocrine cell densities evaluated ultrastructurally and with chromogranin A immunostaining. It is concluded that in Zollinger-Ellison syndrome, the trophic effects induced by longstanding hypergastrinemia are strictly selective for enterochromaffinlike cells and are associated with ultrastructural features typical for enterochromaffinlike cell tumors.

Adult↗
PubMed1990

Glycoprotein hormone alpha subunit in endocrine cells of human oxyntic mucosa. Studies on its relation to neuroendocrine tumors.

Expression of the alpha-subunit of glycoprotein hormones is an acquired feature of the endocrine cells of the oxyntic mucosa in patients with sustained serum levels of gastrin, and may be related to the hyperplasia-carcinoid sequence occurring in these patients. In the present study we have investigated the intragastric cellular localization and the circulating levels of alpha-subunit in a patient with Zollinger-Ellison syndrome. In this patient we have found that: 1) Endocrine cells accounted for 2.29% +/- 1.44% of the total oxyntic mucosal volume (normal value: 0.9% +/- 0.4%), with the ECL cells representing 63.22% +/- 10.9% of the total endocrine cell volume (normal value: 29.8 +/- 8.8%). 2) Cells immunoreactive for the alpha-subunit were found to correspond ultrastructurally to a subpopulation of enterochromaffin-like cells, indistinguishable from similar cells devoid of significant immuno-electron microscopic labeling. 3) Immunoreactive cells included a portion of oxyntic endocrine cells with punctate granules, a feature previously observed only in carcinoid tumors of the oxyntic mucosa. 4) In consecutive sections of freeze-dried vapor-fixed biopsies a fraction of alpha-subunit storing cells was found to co-express histamine. 5) The serum alpha-subunit levels were abnormally elevated and paralleled those of gastrin in a secretin-stimulation test. Analysis of similar curves in two other patients with Zollinger-Ellison syndrome, and five patients with hypergastrinemic atrophic gastritis, all presenting alpha-subunit containing oxyntic endocrine cells, showed significant alpha-subunit elevations only in the patients with ulcerogenic syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastric Mucosa↗
PubMed1990

Identification of the endocrine cells detected by the monoclonal antibody HISL-19 in human tissues.

The human endocrine cells reacting with the monoclonal antibody HISL-19 were identified with hormone antisera of proven specificity using a double immunostaining procedure. The epitope for HISL-19 was found in all types of pituitary cells except ACTH cells, in thyroid C cells, in all types of adrenal medullary and pancreatic islet cells and in somatostatin and pancreatic polypeptide cells of the gastrointestinal mucosa. No staining was found in parathyroid cells and in most gastrointestinal endocrine cells. Either paranuclear focal accumulation or diffuse cytoplasmic distribution of immunoreactive material were found. The spectrum of HISL-19 immunoreactive cells was found to be only in part complementary to that of cells immunoreactive for chromogranin A. Thus, it is concluded that the monoclonal antibody HISL-19 is a useful addition to other immunohistochemical markers for the detection of cells showing neuroendocrine features.

Adrenal Medulla↗
PubMed1989

Composite carcinoid-adenocarcinoma of the stomach associated with multiple gastric carcinoids and nonantral gastric atrophy.

A case of multiple gastric carcinoids and nonantral atrophic gastritis in which the larger tumor was a composite carcinoid-adenocarcinoma is presented. The two components of the composite tumor immunohistochemically showed clear-cut diverging functional differentiations although the available evidence supported a common histogenesis from the metaplastic intestinal epithelium of the gastric mucosa. The carcinoid tissue of the composite tumor, which showed "atypical" features, also differed from the other, pure carcinoids, in which the histologic appearance was "typical." Total gastrectomy performed 1 month after the original gastric resection with antrectomy disclosed regressive changes in the endocrine cell proliferations of the gastric stump consistent with the withdrawal of a stimulating effect of the antral gastrin.

Adenocarcinoma↗
PubMed1989

Quantitative electron microscopy of endocrine cells in oxyntic mucosa of normal human stomach.

An ultrastructural morphometric study of the endocrine cells of the oxyntic mucosa of the stomach in gastric biopsies collected from five male and five female healthy volunteers aged 19-31 was performed. No sex-related differences were disclosed. Endocrine cells accounted for 1.2 +/- 0.4% of the epithelial volume and 0.9 +/- 0.4% of the mucosal volume, i.e., including the lamina propria. After classification of the specific endocrine cell types according to the ultrastructural morphology of secretory granules, the volume densities of ECL, P and D cells (30 +/- 9%, 24 +/- 7%, and 22 +/- 4% of the entire endocrine cell mass, respectively) were higher than those of other endocrine cell types. In particular, EC cells contributed less than 10% and X cells represented a very low proportion of the total cells. Non-granulated profiles of cells which in all other respects appeared to be endocrine were also found with a volume density of 8 +/- 4%. D cells were distinguished by the high fraction of cytoplasm occupied by secretory granules (31 +/- 5%). Subdivision of the whole mucosa into four horizontal segments revealed the endocrine cells to be mostly distributed in the three lower, with virtually no endocrine cells in the superficial segment. The quantitative ultrastructural analysis of the endocrine cell population of the normal human oxyntic mucosa provided by this study may allow a better evaluation of physiological and pharmacological variations of the endocrine cell population.

Adult↗
PubMed1989

Structure and function of endocrine cells in the oxyntic (acid-secreting) mucosa of human stomach.

The morphological and functional characteristics of the endocrine cells of the oxyntic (acid-secreting) mucosa of the human stomach, a target of the trophic effect of gastrin, are reviewed. In healthy subjects these cells account for 0.90 +/- 0.35% of the volume of the entire mucosa and for 1.21 +/- 0.44% of the volume of the epithelial mucosal component alone. The cells show no extension to the glandular lumen and show an intimate anatomic relationship with contiguous non-endocrine epithelial cells. This configuration indicates undefined local functions of the paracrine type not influenced by the gastric lumen content. Seven cell types were identified ultrastructurally, three of which (enterochromaffin-like (ECL), P and D) cumulatively account for more than 75% of the total endocrine cell mass. The secretory product(s) of the endocrine cells has not been demonstrated definitively with the exception of minor cell populations producing glucagon (only in the fetal life), somatostatin and 5-HT. Recently, production of histamine and glycoprotein hormone alpha-subunit by oxyntic endocrine cells of man have been reported. However, histamine seems to occur in these cells normally, whereas the production of glycoprotein hormone alpha-subunit appears to be virtually restricted to cells of patients with hypergastrinaemic conditions.

Animals↗
PubMed1988

Nonrandom expression of polypeptide hormones in pancreatic endocrine tumors. An immunohistochemical study in a case of multiple islet cell neoplasia.

One hundred four endocrine tumors found in the body and tail of the pancreas of a patient with the Zollinger-Ellison syndrome (ZES) and multiple endocrine neoplasia (MEN-I) were investigated by immunohistochemistry for insulin, glucagon, somatostatin, pancreatic polypeptide (PP), and gastrin. The results for each tumor were scored into six grades according to the frequency of immunoreactive cells. Pancreatic polypeptide, glucagon, insulin, and somatostatin were demonstrated in 96, 80, 62, and 42 tumors, respectively. When only the higher scores of cell frequency (3-5) were considered, PP and glucagon (accounting for 71 and 49 tumors, respectively) differed markedly from insulin (two tumors) and somatostatin (0). The frequency of PP-immunoreactive cells was higher in tumors of large size whereas that of glucagon cells was higher in the smaller neoplasms. No significant associations of the tumoral hormonal expressions were found with the type of histologic structure (trabecular versus gyriform), the occurrence of stromal fibrosis, and the intrapancreatic location of the neoplasms, except for a higher number of somatostatin cells in fibrotic tumors. Gastrin-immunoreactive cells never were found in the tumors in spite of the concomitant hypergastrinemia. In conclusion, the nonrandom expression of the hormonal phenotype by the neoplastic islet cells, as shown by the immunohistochemical, semiquantitative analysis of a large number of tumors, suggests that in our MEN-I patient the genetically determined neoplasms also are affected by other mechanisms, possibly nongenetic.

Aged↗
PubMed1988

Ultrastructure of a neuroendocrine complex in oxyntic mucosa of normal human stomach.

The occurrence and ultrastructural characteristics of an extraepithelial neuroendocrine complex found in the oxyntic mucosa of a healthy young adult subject are described. The complex is composed of endocrine cells (P and ECL types) identical to those located intraepithelially and peripherally located axons embraced by cytoplasmic extension of scattered Schwann cells.

Adult↗
PubMed1988

Comparative study of seven neuroendocrine markers in pancreatic endocrine tumours.

A comparative immunocytochemical investigation was performed on a series of 59 pancreatic endocrine tumours using a panel of seven markers for neuroendocrine neoplasms: neurone specific enolase (NSE), PGP 9.5, chromogranin A (CgA), PHE5, prealbumin (Pa), HISL-19, and alpha-subunit of human chorionic gonadotropin (alpha-HCG). Most markers can be separated into two groups characterized by an identical immunoreactive cellular compartment and substantial overlapping in the immunohistochemical results. The first group comprises soluble cytoplasmic proteins such as NSE and PGP 9.5 and is characterized by a diffuse, homogeneous staining of the cell cytoplasm that is not related to the type of hormone produced or the degree of cell differentiation. The second group includes antigens located in the cell secretory granules such as CgA, PHE5, Pa and HISL-19 and is characterized by a heterogenous, often polarized cell staining. The latter markers strongly react with benign glucagonomas and PP-omas and, in contrast with those of the former group, are strictly neuroendocrine-specific. However, they often are less effective in staining insulinomas and malignant tumours. An additional, distinctive and useful characteristic of the HISL-19 antibody was its ability to label the Golgi complex also in tumours with absent granular staining. Finally, alpha-HCG was found in 9 of 16 malignant tumours (mostly glucagonomas and insulinomas) and in 4 of 43 benign neoplasms (all insulinomas). The latter finding is not in accordance with the reputed specificity of the alpha-HCG expression by pancreatic endocrine tumours as a marker for tumour malignancy.

Adenoma, Islet Cell↗
PubMed1988

Expression of glycoprotein hormone alpha-subunit by endocrine cells of the oxyntic mucosa is associated with hypergastrinemia.

Previous studies have shown that hyperplastic endocrine cells of the oxyntic mucosa in patients with atrophic gastritis may express immunoreactivity for the alpha-subunit of human chorionic gonadotropin (alpha-HCG, common to all glycoprotein hormones). Since this endocrine proliferation is regarded as dependent on the trophic effect of the concomitant hypergastrinemia, the relation between immunohistochemical expression of alpha-HCG by oxyntic endocrine cells and serum levels of gastrin were investigated. The study was performed on endoscopic gastric biopsies of the oxyntic mucosa from 49 patients subdivided into the following groups: A) with histologically normal mucosa and normogastrinemia (22 cases), B) with atrophic gastritis and normogastrinemia (12 cases), C) with normal mucosa and hypergastrinemia (Zollinger-Ellison syndrome, retained antrum) (7 cases) and D) with atrophic gastritis and hypergastrinemia (with or without pernicious anemia) (8 cases). The alpha-HCG immunoreactive cells were found in all hypergastrinemic patients (groups C and D), regardless of the concomitant pathological condition of the mucosa. These cells accounted for 7.8% to 44.7% of the number of Grimelius argyrophil cells in consecutive serial sections. In contrast, alpha-HCG-containing cells were exceptional or absent in most normogastrinemic patients. Their number was sizable in only two cases of group A and three cases of group B, where it ranged from 2.5% to 14.8% of the number of argyrophil cells. It was concluded that expression of alpha-HCG is another feature of oxyntic endocrine cells associated with hypergastrinemia in addition to those previously recognized such as development of hyperplasia and/or carcinoid tumors.

Adolescent↗
PubMed1988

Histopathological classification of nonantral gastric endocrine growths in man.

Recently, the gastric endocrine system has been recognized as the origin of benign and malignant tumors in pernicious anemia. It has also been found that the gastric endocrine cells respond to permanent elevation of serum gastrin levels induced by changes in acid secretion in response to surgical procedures, drug therapy and age. Therefore, a definition of nonantral gastric endocrine hyperplasia (simple or diffuse, linear or chain-forming, micronodular, adenomatoid), dysplasia (enlarging or fusing micronodules, microinvasion, nodular growth) and neoplasia (intramucosal carcinoid, invasive carcinoid) is presented. The individual entities are illustrated, together with the literature discussed and the techniques for their identification presented.

Endocrine System Diseases↗
PubMed1988

Immunocytochemical patterns of islet cell tumors as defined by the monoclonal antibody HISL-19.

A series of 51 islet cell tumors removed from 28 patients was investigated immunohistochemically with the monoclonal antibody HISL-19. The antibody was produced after immunization of BALB/c mice with human islet cells and was found to react with a wide range of neuroendocrine and neural cells. All tumors presented positive immunoreaction showing various combinations of 2 basic patterns. The first pattern reflected the immunostaining of the secretory granules of the tumor cells. This "granular" staining was predominantly associated with benign neoplasms and with the tumoral production of glucagon and pancreatic polypeptide (PP), while it was absent or inconsistent in most insulin-secreting tumors. The second pattern consisted of focal immunoreactive aggregates located in a peri- (and, in polarized cells, supra-) nuclear position. This "cluster-type" staining showed a good morphologic and topographic correspondence with the Golgi apparatus of the cells of the same tumors, as shown by electron microscopy. The latter pattern was well represented in all types of islet cell tumors except those producing PP. Moreover, it was more apparent in less differentiated tumors in which the granular pattern was often absent or inconsistent. Cluster-type (but not granular) immunoreactivity was frequently found in some nonendocrine, nontumoral pancreatic structures, particularly in the epithelium of small ducts. However, the immunoreactive aggregates of nonendocrine cells were distinctly less prominent than those of endocrine cells. On the basis of a comparison with other immunohistochemical markers for neuroendocrine cells, it is concluded that the HISL-19 monoclonal antibody presents specific staining characteristics useful for the cytologic analysis of islet cell tumors.

Adenoma, Islet Cell↗
PubMed1987

Immunocytochemical localization of pyrazine-binding protein in bovine nasal mucosa.

Polyclonal antibodies have been raised against purified bovine pyrazine-binding protein, a protein that binds the odorant 2-isobutyl-3-methoxypyrazine. These antibodies have been utilized in immunocytochemical experiments to localize the pyrazine-binding protein in bovine nasal mucosa. Tissue fragments, macroscopically identified as olfactory and respiratory mucosa, were fixed in Bouin's fluid and embedded in paraffin. Consecutive serial sections were processed for immunofluorescence studies and restained either with haematoxylin-eosin or with periodic acid Schiff-Alcian Blue. In both olfactory and respiratory mucosa, only seromucous tubulo-acinar glands were specifically labelled. These glands are located in the lamina propria underlying typical respiratory epithelium, even in those tissues that are macroscopically defined as olfactory mucosa.

Animals↗