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Biomedical subjects

F Carlei

Publications and source records attributed to F Carlei.

At least 55 records · Page 3Linked to original sources
PubMed1990

Immunocytochemical study of endocrine cells in pelvic ileal reservoirs.

The distribution and morphology of intestinal endocrine cells was investigated in the mucosa of pelvic ileal reservoirs using immunocytochemical methods. Endoscopic biopsies were obtained from 15 patients after the construction of a modified J-pouch. The mucosa of the reservoir showed a variable degree of colonic metaplasia in all cases. No relevant quantitative variations of gut endocrine cells were detected, as revealed by immunostaining for the general marker, chromogranin, compared with normal ileal mucosa. Immunostaining for different peptide-containing cells resulted in normal number and morphology of serotonin, enteroglucagon, peptide tyrosine-tyrosine, and somatostatin-containing cells. Neurotensin cells were less numerous than in normal mucosa. The role played by gastrointestinal hormones in the adaptive response of the intestine to pouch construction is, presently, unclear. Further studies involving measurements of fasting and meal-stimulated levels of gut hormones in pouch patients might clarify this aspect.

Adult↗
PubMed1990

[Changes in the prostanoid content and the population of endocrine cells in jejunal biopsies from celiac children].

Prostanoid content prostaglandin E2 (PGE2) and thromboxane B2 (TxB2) and endocrine cells population were evaluated in jejunal biopsies from celiac children; findings were compared to active celiac patients on a challenge diet. Patients were divided as follows: Group A: 14 children with active untreated celiac disease; Group B: 7 celiac children on gluten challenge who had received diet therapy for the past 2 years; Group C: 8 normal control children. Jejunal biopsies were used for endocrine cell population measurement by immunocytochemistry, using a specific marker (chromogranin), and for prostanoid radioimmunological evaluation. The quantitative assessment of the endocrine cell population in Groups A and B revealed a significantly higher number of endocrine cells (20 +/- 11.5; 18.4 +/- 9.8 n. cell/visual field respectively) compared to Group C (8.44 +/- 2.3 n. cell/visual field) (p less than 0.05). In the jejunal extract the PGE2 content (341.8 +/- 82.3) ng/g) for Group A biopsies was significantly higher than that of Group C biopsies (93 +/- 23 ng/g) (p less than 0.05. The PGE2 content (69.4 +/- +13.2 ng/g) for Group B did not show any statistically significant change. In contrast, TxB2 content in jejunal biopsies from all three groups was not significantly different.

APUD Cells↗
PubMed1990

[Functional changes in the biliary system following extrahepatic biliary obstruction].

To assess the potential structural changes of the biliary tree and liver in patients with extrahepatic biliary obstruction, the resected specimens of 20 patients operated for benign biliary stricture were evaluated by means of immunocytochemical and histological methods. Furthermore, liver biopsies were taken for the same purposes. The results showed that in the dilated segment of the hepatic duct proximal to the stricture, innervation was greatly reduced or completely absent with associated advanced morphological and histological changes and high intrabiliary pressure levels. Similar findings were observed in the liver biopsies, too. These biopsies showed advanced morphological and histological changes associated with reduced innervation. By contrast, the nondilated segment of the hepatic duct, distal to the obstruction, showed normal innervation, normal morphology and histology and normal levels of intrabiliary pressure. The present study provides evidence that in cases of extrahepatic biliary obstruction, there are advanced pathological changes in the biliary tree associated with innervation impairment. These structural changes are associated with functional changes in both the liver and the biliary tree. Such functional changes represent a threat to the patient, particularly if major surgery is required. Increased biliary pressure appears to be a major cause of the development of these changes. Biliary drainage, either surgical or endoscopic, is indicated as the only alternative to reduce intrabiliary pressure and to contribute to a reversal of these structural and functional changes.

Bile↗
PubMed1990

[Muciparous cells and endocrine cells of the gallbladder epithelium in patients with uncomplicated cholelithiasis].

In this study the authors have investigated the different morphofunctional features of the gallbladder mucosa in patients with uncomplicated cholelithiasis. Histological changes, type and distribution of endocrine and mucin-producing cells were characterized by immunocytochemistry and mucin histochemistry. The authors attempted to correlate these findings to the number and size of gallbladder stones as well as type of bacteria present in the bile. The results indicate that, despite similar clinical parameters, a wide range of histological changes may occur in the gallbladder mucosa of these patients. Moreover, the presence of some endocrine and mucin-producing cell types in the so called "pyloric metaplasia" led the Authors to hypothesize that the latter may be a trivial event.

Cholelithiasis↗
PubMed1989

The distribution of GAWK-like immunoreactivity in neuroendocrine cells of the human gut, pancreas, adrenal and pituitary glands and its co-localisation with chromogranin B.

GAWK is a recently discovered peptide isolated from extracts of human pituitary gland and subsequently shown to be identical to sequence 420-493 of human chromogranin B. The distribution of this peptide was studied in human gut, pancreas, adrenal and pituitary glands using antisera to two portions of the 74 amino acid peptide (sequences 1-17 and 20-38). In addition, the co-existence of GAWK immunoreactivity with other peptides and chromogranin B was investigated using comparative immunocytochemistry. In the gut, GAWK was localised mainly to serotonin-containing cells of the mucosal epithelium, where electron microscopy showed it to be stored in typical electron-dense (250 nm diameter) granules, and to a moderate population of nerve fibres in the gut wall. Considerable quantities of GAWK-like immunoreactivity were measured in the gut, up to 36.3 +/- 18 pmol GAWK 1-17/g wet weight of tissue (mean +/- SEM) and 12.4 +/- 2.9 pmol GAWK 20-38/g. Chromatography of gut extracts revealed several GAWK-like immunoreactive peaks. GAWK-like immunoreactivity was also detected in endocrine cells of pancreas, pituitary gland and adrenal medulla, where the highest concentrations of GAWK-like immunoreactivity were measured (GAWK 1-17 2071.8 +/- 873.2 and GAWK 20-38 1292.7 +/- 542.7 pmol/g). Endocrine cells containing GAWK-like immunoreactivity were found also to be immunoreactive for chromogranin B. Our results define a discrete distribution of GAWK immunoreactivity in human endocrine cells and nerves and provide morphological support for the postulated precursor-product relationship between chromogranin B and GAWK. Details of the functions of this peptide are awaited.

Adrenal Glands↗
PubMed1989

Heterotopic gastric mucosa of the rectum--characterization of endocrine and mucin-producing cells by immunocytochemistry and lectin histochemistry. Report of a case.

Heterotopic gastric mucosa in the rectum is particularly uncommon; only 23 cases have been reported to date. Moreover, no studies have been done on the neuroendocrine apparatus and glycoprotein production of the heterotopic mucosa. This study reports on a 13-year-old boy, admitted with rectal bleeding and persistent tenesmus. An ulcerative lesion was found on colonoscopy; biopsies revealed a fundic-type gastric tissue. Medical therapy (H2-blockers) promptly healed the rectal ulcer; surgical excision of the heterotopia was performed with complete and permanent relief of symptoms (3-year follow-up). Immunocytochemistry (PAP) revealed 5-Ht and somatostatin cells in the gastric-type mucosa, as in the normal human stomach. These cells also were present in the surrounding rectal epithelium where PYY-enteroglucagon cells were detected, which were absent in the heterotopic tissue. Mucin histochemistry showed PAS-positive cells also strongly stained by LA lectin in the heterotopic tissue, differentiating the rectal epithelium that remained unstained. Therefore, the morphofunctional status (endocrine cells and mucins) of the gastric heterotopia was almost identical to its orthotopic counterpart, confirming the hypothesis that endocrine cells and mucin-producing cells differentiate their metabolic products according to the anatomic and functional activity of the epithelium where they grow.

Adolescent↗
PubMed1989

Structural and functional biliary tree changes secondary to extrahepatic biliary obstruction.

To assess the potential structural changes of the biliary tree and the liver in patients with extrahepatic biliary obstruction, the resected specimens of 20 patients operated on for benign biliary stricture, were evaluated by means of immunocytochemical, histological and scanning electronmicroscopic studies. Furthermore, liver biopsies were taken for the same purposes. Our results showed that in the dilated segment of the hepatic duct proximal to the stricture, innervation was greatly reduced or completely absent with associated advanced morphological and histological changes and high intrabiliary pressure levels. Similar findings were observed in the liver biopsies, too. These biopsies showed advanced morphological and histological changes associated with reduced innervation. In contrast, the nondilated segment of the hepatic duct, distal to the obstruction, showed normal innervation, normal morphological and histological findings and normal levels of intrabiliary pressure. The present study provides evidence that in cases of extrahepatic biliary obstruction, there is a feature of advanced pathological changes in the biliary tree associated with alterations in innervation. These structural changes are associated with functional changes in both the liver and the biliary tree. These functional changes represent a threat to the patient, in particular if major surgery is required. Increased biliary pressure appears to be a major cause of the development of these changes. Biliary drainage, either surgical or endoscopic, is indicated as the sole alternative, to reduce the intrabiliary pressure and to contribute to a reversal of these structural and functional changes.

Bile Ducts↗
PubMed1988

Neuroendocrine innervation of the hepatic vessels in the rat and in man.

An extensive array of nerve fibers ramify around the afferent blood vessels of the liver and the extrahepatic and intrahepatic biliary pathways, and are thought to be involved in regulation of blood flow. Although the role of sympathetic innervation is established, little is known about the location or role of regulatory peptidergic innervation in the liver. We examined the anatomic distribution of a wide variety of regulatory peptides and several neural antigens by in situ immunohistochemistry in the rat and in man. A rich peptidergic plexus of nerve fibers and ganglion cells was observed around the arterial vessels in both species, with intense immunoreactivity for neuron-specific enolase, neurofilaments, neuropeptide Y, substance P, and vasoactive intestinal polypeptide. S-100 protein immunoreactivity was seen principally in large nerve bundles, suggesting that the majority of nerves in this area were unmyelinated. In contrast, the portal vessels revealed very little peptidergic innervation. No staining was observed with antibodies directed against insulin, glucagon, gastrin, serotonin, met-enkephalin-Arg-Gly-Leu, cholecystokinin, or growth hormone. These findings indicate the presence of a rich, although selective, peptidergic plexus surrounding afferent hepatic blood vessels. This plexus may play an important role in regulation of hepatic blood flow.

Animals↗
PubMed1988

Occurrence and developmental pattern of neuromedin U-immunoreactive nerves in the gastrointestinal tract and brain of the rat.

Neuromedin U is a newly described regulatory peptide, found by radioimmunoassay in significant concentrations in both the brain and gut of the rat. The aim of the present study was to localize this peptide immunoreactivity to discrete structures of the gut and brain and to map its distribution using immunocytochemistry. In the gut, neuromedin U was confined to nerve fibres mainly in the myenteric and submucous plexuses and the mucosa of all areas except stomach. Immunoreactive ganglion cells were seen in both ganglionated plexuses and their number did not increase following colchicine administration. This observation and the finding that the population of neuromedin U-immunoreactive nerves in the ileum was not affected by complete extrinsic denervation indicated that the nerves are mostly intrinsic in origin. Colocalization studies revealed neuromedin U and calcitonin gene-related peptide were present in the same myenteric and submucosal ganglion cells. Transection experiments showed that, like calcitonin gene-related peptide-immunoreactive nerves, fibres containing neuromedin U project for very short distances in both an oral and anal direction. At the electron microscopic level, neuromedin U immunoreactivity, demonstrated using the immunogold technique, was localized to large granular vesicles. In the central nervous system, neuromedin U immunoreactivity was localized to fibres which were widespread throughout the brain, except in the cerebellum. The presence of neuromedin U-immunoreactive cell bodies was restricted to the rostrocaudal part of the arcuate nucleus. Colocalization studies showed that a proportion of the neuromedin U-immunoreactive cell bodies in the arcuate nucleus also contained pro-opiomelanocortin. Neuromedin U-immunoreactive fibres were first detected in the rat intestinal mucosa at day 1 after birth. In the brain, the arcuate nucleus showed neuromedin U-immunoreactive neuronal cell bodies at E16 but not at E14. In conclusion, neuromedin U is a new member of the group of molecules known as brain-gut peptides.

Aging↗
PubMed1987

Prostanoids in jejunal biopsy specimens of celiac children with active disease and on challenge diet. Radioimmunologic evaluation.

Prostanoid generation (prostaglandin E2 and thromboxane B2) in jejunal biopsy specimens from celiac patients was evaluated, comparing celiac patients with celiac patients on challenge diet and controls. Generation of prostaglandin E2 in jejunal specimens from 14 children with active celiac disease was significantly higher (341.8 +/- 82.3 ng/g; mean +/- SEM) than that from 7 celiac patients on gluten challenge diet (69.4 +/- 13.2 ng/g) or 8 normal children (92 +/- 23 ng/g) (p less than 0.05). In contrast, thromboxane B2 generation in jejunal specimens from all three groups did not show any statistically significant variation. Our results indicate that prostaglandin E2 generation is not merely related to the activity of clinical symptoms, since patients receiving gluten challenge had prostaglandin E2 levels that did not differ from those of controls.

Adolescent↗
PubMed1987

Action of famotidine and ranitidine on prostaglandin E2 (PGE2) content of fundic and duodenal mucosa in duodenal ulcer patients.

PGE2 plays an important role in gastric cytoprotection. Previous experience has shown that H2-blocker drugs may have a role in gastric cytoprotective mechanisms. The effects have been compared of ranitidine and famotidine on PGE2 content in duodenal ulcer patients. Twenty patients were treated for 4 weeks as follows: group A, ranitidine (150 mg twice daily); group B, famotidine (40 mg daily). The patients underwent EGDS before and after therapy. The results show that both famotidine and ranitidine significantly increase the PGE2 content of fundic mucosa (from 112.3 +/- 73 to 210.7 +/- 106 ng/g wet wt and from 109.6 +/- 52.4 to 230.2 +/- 104.6 ng/g wet wt, respectively) in duodenal ulcer patients (p less than 0.01). Similarly, the PGE2 content of duodenal mucosa significantly increases after famotidine treatment (from 51.9 +/- 27.5 to 105.3 +/- 55.6 ng/g wet wt) as well as ranitidine treatment (from 53.8 +/- 24 to 172.6 +/- 72.9 ng/g wet wt) (p less than 0.01). It is concluded that these drugs play an important role in gastric and duodenal cytoprotection.

Adult↗
PubMed1986

Correlation between tyrosine hydroxylase immunoreactive cells in tumors and urinary catecholamine output in neuroblastoma patients.

The results of an immunocytochemical evaluation of tyrosine hydroxylase (TH) immunoreactivity in 30 neuroblastic tumors of infancy are reported. Although no correlations could be found between the immunoreactive pattern and the site of origin or the staging of the tumor, a positive relationship between the urinary catecholamine output and the density of TH-immunoreactive cells could be established. TH was mostly localized on the cytoplasm of the differentiating neuroblasts, whereas immature elements were rarely positive. Moreover, 2 stage IVS cases did not contain any TH immunoreactivity. The possible significance of this finding in the investigation of this form of neuroblastoma, which has a peculiar biological behavior, is considered.

Catecholamines↗
PubMed1986

Gut endocrine cell population in coeliac disease estimated by immunocytochemistry using a monoclonal antibody to chromogranin.

Abnormalities of gut endocrine responses, as well as changes in the number of different endocrine cell types, have been reported convincingly in coeliac patients. Nevertheless, no estimation of total numbers of gut endocrine cells has yet been made in well defined groups of coeliacs. In this study, we have visualised all endocrine cell types in jejunal biopsies from coeliac patients with active and quiescent disease as well as in controls, using a monoclonal antibody to chromogranin. This protein was purified originally from bovine adrenal medulla and is known to be a reliable marker for all endocrine cells of the gut. The following groups were considered: (a) nine coeliacs with active illness, (b) 10 coeliacs under gluten-free diet, (c) eight coeliacs receiving gluten challenge, (d) five non-coeliacs (controls). Histological (haematoxylin and eosin) and immunocytochemical (peroxidase anti-peroxidase) stains were applied to 3 micron paraffin sections. Quantitative estimation of endocrine cell density was made using four different methods in order to evaluate the results fully (number of cells/mm2, number of cells/visual field, number of cells/8 crypts-villi, number of cells/unit of length of muscularis mucosae). In patient groups (a) and (c), coeliacs with active disease and coeliacs on gluten challenge diet respectively, a significantly higher number of endocrine cells was observed in comparison with normal controls (group d). In group (b) patients, coeliacs on gluten-free diet, no significant changes in the number of endocrine cells were observed in comparison with controls. Our results show that a significant increase in endocrine cell density exists in coeliacs with active illness (groups a and c), in comparison with controls. This condition is resolved in coeliacs receiving a gluten-free diet (group b).

Antibodies, Monoclonal↗
PubMed1986

Occurrence and distribution of a newly discovered peptide, galanin, in the mammalian enteric nervous system.

Galanin, a newly discovered peptide, was found throughout the gastrointestinal tract of man, pig, and rat, exclusively in nerves. The concentrations of immunoreactive galanin ranged from 3.7 +/- 0.7 (mean +/- SEM) pmol/g in rat antrum to 76.5 +/- 14.3 pmol/g in pig colon. The predominantly intrinsic origin of the galanin nerves was shown by the finding of the peptide in submucosal ganglion cells, the majority of which also contained VIP. Furthermore, neither extrinsic denervation of the gut nor administration of capsaicin, which selectively destroys extrinsic afferent fibres, had any significant effect on the galanin innervation. The caudal projection of galanin-immunoreactive fibres was demonstrated by complete transection of the gut, which led to their reduction in the 1 to 2 cm distal to the cut. The abundance of galanin in the innervation of the mammalian gut and its reported action on smooth muscle contractility suggest this peptide to be a novel regulatory factor in the control of bowel function.

Animals↗
PubMed1986

Immunocytochemical study of a trabecular carcinoma of the skin (Merkel cell tumor). Case report.

The existence of different neuroendocrine markers was investigated by immunocytochemistry in a case of Merkel cells tumor. Neuroplastic cells contain NSE,NF,CK and chromogranin A i.r. On the basis of the results the neuroendocrine nature of this uncommon neoplasm of the skin is confirmed and it is suggested that chromogranin A could represent an additional marker for Merkel cells tumors.

Adenocarcinoma↗
PubMed1985

Occurrence, distribution and nature of neuropeptide Y in the rat pancreas.

Significant quantities of a newly discovered peptide, neuropeptide Y, were found in the rat pancreas, where they were localized to nerves in the exocrine parenchyma and around arterial and ductal structures. Although unaffected by surgical parasympathectomy, the periarterial and periductal nerves were abolished by chemical sympathectomy, suggesting that NPY is partially costored with sympathetic transmitters in nerve fibers.

Animals↗