Impaired response of gastric vessels to prostaglandin E2 in rats with persistent obstructive jaundice.

We investigated the response of gastric vessels to prostaglandin (PG) E2 after intra-duodenal release of bile in rats with obstructive jaundice. The animals were divided in four groups according to duration of bile duct obstruction (BDO): control and 1 week (W), 2W, and 3W groups. Prolonged BDO decreased gastric mucosal blood flow (BF) significantly. The BF recovered after the release of BDO in the 1W and 2W groups, but not in the 3W group. BDO decreased PGE2 content in gastric mucosa in the 1W, 2W, and 3W groups. PGE2 decreased vascular perfusion pressure of the isolated stomach in the control and 2W groups, but not in the 3W group. The response of gastric vessels to PGE2 was poor in the 3W group compared with the control and 2W groups. Decreased PGE2 in the gastric mucosa and decreased response of gastric vessels to PGE2 may affect gastric blood flow in obstructive jaundice.

Induction of apoptosis in a human hepatocellular carcinoma cell line by a neutralizing antibody to transforming growth factor-alpha.

A cell line derived from a Japanese man with hepatocellular carcinoma was established in culture and designated OCUH-16. The cell line has the morphological and chromosomal features of hepatocellular carcinoma cells and has a short doubling time (approximately 33 h). OCUH-16 cells were shown to express transforming growth factor-alpha (TGF-alpha) in addition to albumin, DNA polymerase-alpha, c-JUN, and the retinoblastoma gene product. Electron microscopy revealed TGF-alpha immunoreactivity associated with the cell membrane, but TGF-alpha was not detected in medium conditioned by OCUH-16 cells by enzyme-linked immunosorbent assay. Reverse transcription and polymerase chain reaction analysis revealed the presence of TGF-alpha messenger RNA in these cells. Culture of OCUH-16 cells in the presence of a neutralizing antibody to TGF-alpha inhibited cell proliferation and induced many cells to undergo apoptosis (programmed cell death). These observations suggest that endogenous TGF-alpha is necessary for OCUH-16 cell growth.

Etiological involvement of Helicobacter pylori in "reflux" gastritis after gastrectomy.

OBJECTIVES: "Reflux" gastritis after gastrectomy is associated with various symptoms that are often detrimental to the patients' quality of life. However, prevention of the reflux does not always bring relief from the symptoms of gastritis. Helicobacter pylori (H. pylori) is now considered one of the most important pathogenetic factors in gastritis. The association between H. pylori infection and reflux gastritis after gastrectomy was investigated in the present study. METHODS: In total, 115 patients who had undergone gastrectomy were entered in this study. Five biopsy specimens from the gastric remnant were taken during upper GI endoscopy. One specimen was examined pathohistologically, and the remaining four were examined for H. pylori infection. The histological degree of gastritis was determined according to the score system of Rauws et al. RESULTS: Forty-six patients (40%) demonstrated H. pylori infection in their stomachs. The prevalence of the infection was significantly higher in patients with conventional gastrectomy than in those with subtotal gastrectomy. The prevalence of H. pylori infection was significantly lower in patients who had undergone gastrectomy more than 4 yr ago. The histological gastritis score in patients with H. pylori infection was significantly higher than in those without H. pylori infection. Furthermore, the eradication of H. pylori in patients with both serious gastritis symptoms and no bile reflux improved the symptoms and significantly decreased the histological gastritis score. CONCLUSIONS: The results suggest that H. pylori is a factor in the pathogenesis of reflux gastritis after gastrectomy.

Expression of antigens related to apoptosis and cell proliferation in chronic nonsuppurative destructive cholangitis in primary biliary cirrhosis.

The initial injury in primary biliary cirrhosis (PBC) is the destruction of portal bile ducts. Little information is available on apoptosis and cell proliferation in such bile ducts, so we used immunohistochemical techniques to locate molecules related to apoptosis [Fas antigen, Lewis Y antigen (BM1/JIMRO), and bcl-2 protein] and to cell proliferation (proliferating cell nuclear antigen, PCNA) in 21 patients with PBC. In addition, nick-end labelling was done to locate DNA fragmentation. The expression of these molecules in chronic nonsuppurative destructive cholangitis (CNSDC) was examined. Cell death and PCNA expression were both found in portal bile ducts affected by CNSDC in 7 of the 13 CNSDC patients examined. Fas antigen was found on the plasma membrane and rough endoplasmic reticulum of bile-duct cells with CNSDC in the frozen sections of all 6 patients with CNSDC out of the 9 patients inspected, and this antigen was found also in bile-duct cells without CNSDC in 2 of these 9 patients. It was not found in anatomically normal liver (from 2 patients with Gilbert's disease). The Lewis Y antigen was found in bile ducts with CNSDC and in proliferated ductules in all 16 patients examined. No bcl-2 protein was found in any bile-duct or ductule cells, but it was found in the cytoplasm of lymphocytes surrounding or invading CNSDC. DNA fragmentation was found in the nuclei of bile-duct cells with CNSDC by nick-end labelling. Our study indicated that Fas-mediated apoptosis might be involved in CNSDC, but that bcl-2 protein seems to participate less than Fas. Although the Lewis Y antigen was found in many bile ducts, the relationship between the antigen and apoptosis remains unknown because there was no evidence that this antigen mediates apoptosis.

Inhibitory effect of dopamine on gastric motility in rats.

BACKGROUND: There is disagreement with regard to the involvement of dopamine (DA) receptors in gastric motility. The mechanisms of the inhibitory effect of DA on rat gastric motility was investigated in association with acetylcholine (Ach) release in the present study. METHODS: In vivo vagotomized, splanchnicectomized rats and control rats were used, and gastric movement was determined as the gastric motility index after DA administration. In vitro study of Ach release from the circular muscle strips of the gastric corpus was investigated after administration of domperidone, SCH23390, phentolamine, or propranolol. RESULTS: In the in vivo study DA inhibited gastric motility in a dose-dependent manner. Vagotomy and splanchnicectomy had no effect on the inhibitory effect of DA. In vitro study DA inhibited [3H]-Ach release in a dose-dependent manner. The inhibitory effect of DA was antagonized by domperidone but not by phentolamine, propranolol, or SCH23390. CONCLUSIONS: Inhibition of gastric motility by dopamine is independent of extrinsic innervation and seems to be mediated by DA2 receptors in the gastric wall.

Telomere shortening in chronic liver diseases.

We measured the telomere length in patients with chronic hepatitis or liver cirrhosis and found a significant telomere shortening in the liver with chronic liver disease compared to that in the normal liver. The telomere length tended to decrease with the progression of chronic liver disease.

[A case of spontaneous mesenteric fibromatosis occurred from the mesentery of the small intestine].

The fibromatosis is benign tumor which is characterized by the remarkable proliferation and the invasive growth of fibrous tissue and no distant metastasis. It usually occurs from the abdominal wall or the extremities, and rarely from the mesentery. A 54-year-old male complained of an epigastralgia and emesis. He was diagnosed through imaging as the obstructive ileus by abdominal tumor. The laparotomy was performed and a round, egg sized tumor was found wear by dilated ileum. The tumor was considered to occur from the mesentery, and the iliectomy with the tumor was completed. It was suggested that ileus occurred in the early stage because the tumor was located just by the ileum.

[Residual gastritis after gastrectomy and Helicobacter pylori--its clinical significance].

Residual gastritis after gastrectomy brings the various symptoms such as abdominal pain, nausea, emesis and loss of appetite, and often hazards quality of life of the patient. Bile reflux to the stomach is believed as one of the important pathogenesis of residual gastritis, however the prevention for bile reflux cannot always heal the gastritis. Helicobacter pylori (H. pylori) is considered as one of the most important pathogenesis of gastroduodenal ulcer and gastritis, and H. pylori may possibly cause residual gastritis after gastrectomy. However, the association between infection with H. pylori and the residual gastritis has not revealed yet. In the present study, the association with H. pylori and the residual gastritis after gastrectomy was investigated in 56 patients who had undergone gastrectomy before. Twenty-four patients (42.9%) had H. pylori infection at their stomachs and the incidence of the infection in the patients with gastrectomy was significantly higher with subtotal gastrectomy. As for the histological gastritis score of Rauws (Rauws' score), Rauws' score of H. pylori positive group was significantly higher than H. pylori negative group. Furthermore, the eradication of H. pylori for the patients with serious symptoms of gastritis improved the symptoms and decreased significantly Rauws' score. These results suggest that H. pylori was associated with the pathogenesis of residual gastritis after gastrectomy.

Protein kinase C alpha-, beta- and gamma-subspecies in basal granulated cells of rat duodenal mucosa.

Protein kinase C [cPKC: alpha, beta (beta I, beta II), gamma], a Ca(2+)- and phospholipid-dependent enzyme, has been thought to play a critical role in the synthesis and secretion of gut hormones in gastrointestinal mucosa. However, the localization of PKC has not yet been clarified at the cellular level in the gastrointestinal epithelium. The present study was made to identify cPKC-containing cells immunohistochemically in the rat duodenal epithelium by light and electron microscopy and by confocal laser scanning microscopy. Special attention was paid to the demonstration of cPKC in basal granulated cells. By light microscopy, some duodenal epithelial cells were demonstrated to be immunopositive for PKC alpha-, beta- and gamma-subspecies. Their distribution and incidence were almost similar to those of cells stained by the silver impregnation method of Grimelius. By electron microscopy, profiles of secretory granules were found at the basal region of the PKC-immunopositive epithelial cells. When the cells were double-immunostained for gastrin, serotonin or somatostatin and for PKC alpha-, beta- or gamma-subspecies, these gut hormones and PKC subspecies were shown to colocalize as examined by confocal laser scanning microscopy. These findings show that cPKC (alpha, beta, gamma) is present in basal granulated cells such as G-, EC- and D-cells, presumably playing some important role in regulation of gut hormones, including their synthesis and/or secretion.

Expression of the retinoblastoma gene product in human hepatocellular carcinoma.

Using the mouse anti-human retinoblastoma gene product (pRB) monoclonal antibody, PMG3-245, pRB was detected immunohistocytochemically in human hepatocellular carcinoma (HCC) tissues and a human HCC cell line, designated OCUH-16, recently established in our laboratory. This antibody reacted with human pRB and yielded a single band of approximately 110 kd from cultured OCUH-16 cells. The granules that stained for pRB were found mostly in the HCC cell nuclei, with a few granules observed in the rough endoplasmic reticulum by electron microscopy. Most of the stained granules were located in the euchromatin-rich areas. The percentage of OCUH-16 cells that expressed pRB or DNA polymerase alpha (DNA-PA) decreased over time as the number of OCUH-16 cells increased. The number of HCC cells that stained for pRB in the biopsy specimens from 11 patients varied and pRB expression was well maintained in early and advanced HCC. The level of pRB expression did not correlate with the differentiation of HCC cells or the clinical prognosis. The expression of pRB statistically correlated with that of DNA-PA (P < .01; r = .92). Some sinusoidal cells also stained for pRB. These findings imply that large deletions in the pRB gene are rare in the initiation or promotion of HCC. The correlation between pRB and DNA-PA may suggest that stained pRB participates in the proliferation of both HCC and non-HCC cells.

Immunohistochemical study of dopamine in rat gastric mucosa with acute gastric ulcer.

Recent studies have shown the presence of dopamine (DA) in gastric and duodenal mucosa, and changes in gastric mucosal DA content have been observed in patient with acute ulcers. Immunohistochemical demonstration of the distribution of DA in gastric mucosa under stress was studied by light and electron microscopy. In the control group, DA was present in the gastric gland proper in the gastric corpus and antrum on light microscopy, and on the surface of mucous granules in chief cells, mucous neck cells, and surface epithelium on electron microscopy. In the stress group, DA in gastric mucosa was almost undetectable on light and electron microscopy. Further, in this group serum DA concentration was significantly higher in the portal vein than in the abdominal aorta. Endogenous DA in gastric mucosal cells may affect gastric mucosa differently from exogenous DA, and stress may release endogenous intracellular DA into extracellular spaces.

Immunohistochemical analysis of retinoblastoma gene product (pRB) expression in malignant and non-malignant liver diseases.

The retinoblastoma gene product is a nuclear phosphoprotein that undergoes cell cycle-dependent changes in its phosphorylation status. To analyze the expression of retinoblastoma gene product in the process of liver regeneration and the initiation of hepatocellular carcinoma, we studied immunohistochemically the expression of retinoblastoma gene product and DNA polymerase alpha (DPA) in 33 patients with various liver diseases. Only a few hepatocytes positive for retinoblastoma gene product were found in undamaged, nonregenerating liver tissues, whereas many hepatocytes positive for retinoblastoma gene product were detected in specimens of regenerating liver obtained from patients with acute or chronic liver diseases. Similarities were found between distribution patterns of hepatocytes positive for retinoblastoma gene product and those of hepatocytes positive for DPA, and a highly significant positive correlation was found between the number of hepatocyte nuclei stained for retinoblastoma gene product per 1000 nuclei examined (R-LI) and the number of hepatocyte nuclei stained for DPA per 1000 nuclei examined (D-LI) in tissues obtained from patients with nonmalignant liver disease. Hepatocellular carcinoma cells positive for DPA were detected in the 14 hepatocellular carcinoma specimens tested. In ten of these specimens, hepatocellular carcinoma cells positive for retinoblastoma gene product were found but not in the other four. For all hepatocellular carcinoma specimens, R-LI was proportional to D-LI. Thus in both nonmalignant and malignant liver, retinoblastoma gene product increased in proportion to proliferation of hepatocytes or hepatocellular carcinoma cells.

[A case report of allergic granulomatous angitis with the perforation of ileum].

A case of allergic granulomatous angitis (AGA) complicated with the perforation of the ileum was described. A 52-year-old male had suffered from bronchial asthma since 1990, and two years later he had severe attack of asthma and manifestation of systemic vasculitis. He was diagnosed a AGA with the symptom of vascultitis, history of asthma, and the abnormal hematological findings (WBC 13000/mm3, eosinophilia 11.1%, IgE 1290U/ml, RA 2+). The treatment with adrenal corticoid hormone was started. In April 1992, he complained of severe right lower abdominal pain. He was diagnosed the gastrointestinal perforation by the abdominal X-ray examination and emergency operation was performed. Two ileal perforations were found at the operation and the ileectomy was carried out. Only 11 cases of AGA complicated with the gastrointestinal perforation have ever been reported in Japan. The perforation occurred often at the small intestine and the poor prognosis was referred. The administration of adrenal corticoid hormone should be continued after operation.

An immunohistochemical study of glucagonoma conducted on the metastatic lymph nodes from a patient with recurrent metastatic glucagonoma: report of a case.

In this report, we briefly present the case of a 67-year-old woman who developed recurrent glucagonoma with lymph node metastasis. An immunohistochemical study of the metastatic tumor revealed immunoreactivity of glucagon and protein kinase C (PKC)-alpha, -beta, and -gamma in the tumor cells, two types of which were seen by electron microscopy. One type had abundant secretory granules and mitochondria, while the other had few granules and mitochondria. Some granules were similar to typical A cell granules and others were atypical. An immunoelectron microscopic demonstration revealed PKC-alpha, -beta, and -gamma immunostaining in the cytoplasm of all the tumor cells, while some secretory granules had PKC immunostaining, and others had no immunostaining. Thus, it appears that metastatic glucagonoma and its associated granules are composed of two types of mature and immature cells or granules. As immunoreactivity of PKC-alpha and -gamma was found in the tumor cells, but not in the normal A cells of the islets of Langerhans, the PKC subspecies alpha and gamma, which are not present in normal pancreatic A cells, may exist in human glucagonoma cells.

Detection of the preneoplastic lesions of small hepatocellular carcinoma in cirrhotic livers.

To identify the preneoplastic lesions of hepatocellular carcinoma and the fine structure of preneoplastic hepatocytes, we studied proliferative conditions in cirrhosis of the liver. In all, 46 foci of cellular alteration (FCA), three regions of adenomatous hyperplasia (ADH), and 21 small hepatocellular carcinomas (sHCC) were studied by published criteria for sHCC and by the proliferative activity of the lesions as examined with monoclonal antibodies against DNA polymerase alpha and proliferating cell nuclear antigen. The four patients with FCA composed of basophilic hepatocytes were classified by the criteria as having sHCC; cells had features similar to those of sHCC. Two of these four patients with FCA were found to have HCC several years later. The number of hepatocytes stained for proliferating cell nuclear antigen was 72 and 81 per 1000 hepatocyte nuclei in the two patients who developed HCC. In one of the three patients with ADH, a sHCC was found 1 year later, and dysplastic hepatocytes from the region of ADH in this patient had features similar to those of HCC cells by light and electron microscopy. In this patient, the number of hepatocytes stained for DNA polymerase alpha was 452 per 1000 nuclei. Therefore, FCA and ADH might be preneoplastic lesions of sHCC in cirrhosis of the liver. Preneoplastic hepatocytes seem to be small cells with basophilic cytoplasm, with a large nucleus to cytoplasm ratio, finely indented nuclei with a smaller amount of condensed chromatin than normal, and poorly to moderately developed organelles.

A case of benign schwannoma of the thoracic wall mimicking a malignant tumor.

A fist-sized tumor mainly locating in the right thoracic wall of a 73 year-old woman was found by ultrasonography and computed tomography, although a definitive diagnosis was not obtained because of the tumor extension to the abdominal cavity from the right internal thoracic wall, precluding biopsy. Angiography of the right eleventh intercostal artery demonstrated irregular tumor vessels, indicating malignant nature of the tumor. Therefore en-block resection of the tumor with the right eleventh rib was performed under a thoracotomy. Postoperative histopathological examination showed that the tumor was a benign schwannoma of Antoni type A. Since schwannoma is usually difficult to diagnose preoperatively without histopathological study, it is suggested that patients with schwannoma-like tumors, as represented by the present case, should be treated carefully to avoid excessive surgery including an extensive resection of the surrounding tissue.

Effect of pirenzepine on postoperative gastric secretion.

Post surgical stress ulcers of the upper digestive tract, once developed, is difficult to control depending on the primary disease and associated complications. As to the cause of postoperative stress ulcers, decreased defensive factors such as gastric mucosal blood flow and increased gastric secretions have been pointed out. Recently, pirenzepine hydrochloride has been shown to be a specific antagonist of muscarinic cholinergic M1 receptors and a suppressant of gastric acid secretion. Therefore we studied its effect on gastric secretions in postoperative patients. Twenty one patients admitted for abdominal surgery, excluding gastric surgery, were selected and randomly assigned to the pirenzepine group (10 cases) or control group (11 cases). Since the serum half life of pirenzepine is 10 hours, 20mg of pirenzepine was administered intravenously immediately after the operation and twice daily (9 a.m. and 9 p.m.) from postoperative day 1 until day 7. Gastric secretions and gastric pH were measured preoperatively and daily until day 7. In the control group, significant increases in the volume of secretion and significant decreases in gastric pH were observed after the operation. In contrast, the pirenzepine group had a significantly decreased amount of gastric secretion and the gastric pH was higher than those in the control group. Thus we conclude that pirenzepine decreases gastric secretion and increases gastric pH in postoperative patients. Pirenzepine can be regarded as an effective agent for the control of postoperative gastric hypersecretion and possibly a good prophylactic for postoperative stress ulcers.

Ultrastructural localization of protein kinase C beta-subspecies in the axon terminal of rat neuromuscular junction.

Ultrastructural localization of protein kinase C (PKC) beta-subspecies in neuromuscular junctions of the rat lumbrical muscle was investigated by the immunoperoxidase and immunofluorescence methods. By light microscopy, PKC beta-like immunoreactivity (PKC beta-LIR) was found in the axon terminal expansions as well as in the preterminal axons. By confocal laser scanning microscopy, the staining for PKC beta-like immunoreactivity was more intense in the presynaptic regions just in contact with the acetylcholine receptor stained by FITC-alpha-bungarotoxin. By electron microscopy, PKC beta-like immunoreactivity was distributed non-uniformly in the terminal expansions. In the terminal expansions, PKC beta-like immunoreactivity was accumulated in the presynaptic regions in contact with the post-synaptic folds. This accumulation was approximately 0.1-0.2 microns in diameter, which comprised a part of the presynaptic plasma membrane and a group of synaptic vesicles adjacent to it. Weak immunoreactivity was also found diffusely in the axoplasmic matrix. The discrete presynaptic accumulation of PKC beta-subspecies may represent the strategical localization specialized for the effective regulation of neurotransmitter release.

Analysis of proliferating biliary epithelial cells in human liver disease using a monoclonal antibody against DNA polymerase alpha.

The proliferative activity and ultrastructural characteristics of proliferating biliary epithelial cells were analysed immunohistocytochemically in 39 biopsied liver specimens from patients with acute viral hepatitis, chronic hepatitis and liver cirrhosis using a monoclonal antibody against DNA polymerase alpha (DNA-PA). In acute viral hepatitis with perivenular confluent necrosis, proliferation of typical bile ducts was found frequently in portal areas. In chronic aggressive hepatitis and cirrhosis, ductular proliferation of both typical and atypical forms was found in enlarged portal and periportal areas and in confluent necrotic areas. The number of proliferating biliary epithelial cells that stained positive for DNA-PA was small. There were very few positively stained cells in atypical bile ducts in confluent necrotic areas of cirrhosis. Atypical bile ducts seen in chronic aggressive hepatitis, cirrhosis and acute hepatitis with confluent necrosis were positively stained for both cytokeratins 8 and 19. In cirrhosis, the number of stained biliary epithelial cells in typical bile ducts was larger than the number of such cells in atypical bile ducts (P < 0.01). By electron microscopy, the cells positively stained for DNA-PA were mostly so-called clear cells with irregular nuclei containing coarse nucleoplasm, and a few small cells with scanty cytoplasm and few organelles.

Protein kinase C (alpha, beta, gamma) in Pacinian corpuscle.

Immunocytochemical demonstration of protein kinase C (PKC) subspecies (alpha, beta, gamma) was carried out in Pacinian corpuscles of rat hind feet using monoclonal or polyclonal antibodies against each of these subspecies. The inner core cells and lamellae and the Schwann cell cytoplasm of the nerve fiber innervating the corpuscle were strongly positive for PKC alpha-immunoreactivity (IR). In contrast, the axon terminal and the outer core did not display any positive alpha-IR. Very weak PKC beta-IR was detected in the ultraterminal region of the axon terminal, while the trunk region showed no immunoreactivity. Very faint PKC beta-IR was found also in the lamellar cells located at the periphery of the inner core and the endoneurial fibroblasts in the intermediate layer. PKC gamma-IR was not detected in any part of the corpuscle. The strong PKC alpha-IR in the inner core and the presence or absence of PKC alpha-, beta-, and gamma-IR in the axon terminal are discussed from the point of view of the functional aspects of each part.