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Makoto Yoshiba

Publications and source records attributed to Makoto Yoshiba.

At least 19 recordsLinked to original sources
PubMed2006

Involvement of membrane-type bile acid receptor M-BAR/TGR5 in bile acid-induced activation of epidermal growth factor receptor and mitogen-activated protein kinases in gastric carcinoma cells.

Bile acids, which have been implicated in gastrointestinal-tract cell carcinogenesis, share properties with tumor promoters in that both affect signal transduction pathways responsible for cell proliferation and apoptosis. In the present study, we demonstrate that EGFR-ERK1/2 is activated following treatment of AGS human gastric carcinoma cells with bile acids. EGFR phosphoactivation is ligand-dependent, since treatment of cells with HB-EGF antisera or CM197 (a selective inhibitor of HB-EGF) markedly inhibits deoxycholate (DC)-promoted activation. Membrane-type bile acid receptor (M-BAR)/TGR5 is a recently identified G-protein-coupled receptor (GPCR). In AGS cells, siRNAs that target M-BAR suppress DC-induced phosphorylation of EGFR. Furthermore, introduction of siRNAs targeting ADAM17 transcripts resulted in suppression of DC-induced activation of EGFR and ERK1/2. These results suggest that in AGS cells, DC transactivates EGFR through M-BAR- and ADAM/HB-EGF-dependent mechanisms.

Adenocarcinoma↗
PubMed2006

Acute necrotizing esophagitis: role of nonsteroidal anti-inflammatory drugs.

BACKGROUND: Acute necrotizing esophagitis (ANE) is a rarely described entity that is thought to be a cause of upper gastrointestinal (UGI) bleeding, The present study examined the incidence of ANE among patients with UGI bleeding, as well as the clinical features of ANE, and the coexisting illnesses and medication histories of ANE patients. METHODS: A retrospective analysis of clinical and endoscopic findings and the clinical course in 16 patients with ANE was carried out over a 3-year period. RESULTS: We observed 16 patients (6%) of ANE in 239 patients with UGI bleeding during the 3-year period. The average age of the patients was 62.5 years. The lesions predominantly affected the lower third of the esophagus, and hiatal hernia was the most common (63%) coexisting endoscopic finding. All patients had coexisting disease. Fifty percent of patients with ANE (eight patients) had taken nonsteroidal anti-inflammatory drugs (NSAIDs). ANE also occurred in four patients with diabetic ketoacidosis. Supportive therapy, including parenteral nutrition and administration of a proton pump inhibitor, was effective. CONCLUSIONS: ANE is more common than has been previously reported, and it should be included in the differential diagnosis of UGI bleeding. ANE could be characterized as an "acute esophageal mucosal lesion," particularly in aged patients with hiatal hernia and among those who consume NSAIDs.

Acute Disease↗
PubMed2006

Possible association of vigorous hepatitis B virus replication with the development of fulminant hepatitis.

A 49 year-old man was referred to our hospital for fear of developing fulminant hepatic failure. There had been an outbreak of fulminant hepatitis B in a dialysis clinic in the western part of Honshu, Japan, that resulted in four deaths among six patients. After the sixth patient contracted severe hepatitis, all patients in the unit were screened biweekly for hepatitis B surface antigen (HBsAg) to detect newly infected patients as soon as possible. Our patient was the seventh victim, and on the day he gave a positive result for HBsAg, his hepatitis B virus (HBV) DNA level had reached 1.1 x 10(11) copies/ml as assessed by real time polymerase chain reaction. Sequence analysis of the causal HBV revealed the presence of a mutation in the precore region (nt 1896), two mutations in the core promoter (nt 1762 and nt 1764), and some minor mutations in the P gene that were restricted to the upstream region. These mutations are indicative of a virus with a high replicative rate that cannot secrete HBeAg. Taken together, these findings indicate that it is very likely that the replicative ability of the causal virus was as vigorous as that of HBV in hepatitis B e antigen-positive asymptomatic carriers with markedly high viral titers. The present case report provides clinical evidence of a possible association between the rapid spread of highly replicative HBV before host immunological recognition and the development of fulminant hepatitis.

DNA, Viral↗
PubMed2005

Elevated cyclooxygenase-2 expression in patients with early gastric cancer in the gastric pylorus.

BACKGROUND: Duodenogastric reflux after surgery increases the risk of gastric carcinoma. To determine whether bile reflux influences the development of gastric cancer in patients who have not had surgery, we compared cyclooxygenase-2 (COX-2) immunoreactivity in early gastric cancer originating from the gastric pylorus and that originating from other locations. We also examined the effects of bile acids on the expression and activity of COX-2 in gastric cells in vitro. METHODS: Tumor sections from 79 patients who underwent endoscopic mucosal resection for early intestinal-type gastric carcinoma were stained using a COX-2-specific monoclonal antibody. Immunoblotting of COX-2 was used to assess the effects of bile acids on COX-2 expression and activity in human gastric cell lines. RESULTS: Among the 79 early gastric cancer lesions studied, 13 (16%) arose in the gastric pylorus. In this group, COX-2 immunoreactivity was negative to weak in 38% (5 of 13 lesions) and moderate to strong in 62% (8 of 13 lesions). In the control group, COX-2 immunoreactivity was negative to weak in 70% (46 of 66 lesions) and moderate to strong in 30% (20 of 66 lesions). COX-2 expression was significantly elevated in early gastric cancer located in the gastric pylorus, compared with that in the other locations. In human gastric cell lines, bile acids induced COX-2 expression, mediated by the ERK 1/2 mitogen-activated protein kinase pathway. CONCLUSIONS: COX-2 expression is elevated in early gastric cancer of the gastric pylorus, a common site of gastric cancer. Bile acids induced COX-2 expression in human gastric cell lines, suggesting a role of bile reflux in gastric carcinogenesis.

Adenocarcinoma↗
PubMed2005

Osteopontin expression in proliferated bile ductules: the correlation with liver damage in fulminant hepatitis.

There have been many reports about the severity of hepatic necrosis caused by fulminant hepatitis; however, the relation between proliferated bile ductules and osteopontin (OPN) expression in inflamed areas in each of the clinical forms of fulminant hepatitis has not been described. To analyze the mechanism in the onset of fulminant hepatitis, we classified not only 16 autopsy cases of fulminant hepatitis into two clinical forms--acute and subacute--but also 3 autopsy cases of late-onset hepatic failure (LOHF) associated with fulminant hepatitis, and examined liver specimens by light microscopy and immunohistochemistry and also serum transaminase levels. Histopathologic study revealed that some of the proliferated bile ductules were associated directly with deteriorating hepatocytes and that bile plugs were present in the proliferated bile ductules. The value of the proliferative cell nuclear antigen labeling index (PCNA-L I) for proliferated bile ductules was very high during the acute form of fulminant hepatitis. Immunohistochemical analysis revealed that OPN expression was higher in the proliferated bile ductules of acute-form fulminant hepatitis than in cirrhotic and normal liver bile ducts. Transaminase levels in acute-form fulminant hepatitis were significantly elevated in comparison with levels in the other forms of the disease. Comparison of acute form fulminant hepatitis with the subacute form and LOHF showed OPN expression in proliferated bile ductules and serum aspartate aminotransferase (ALT)max to be decreased in the subacute form of fulminant hepatitis. OPN expression is an important marker of the degree of liver inflammation, and its regulation mechanism is very important to understanding the pathophysiology of fulminant hepatitis.

Acute Disease↗
PubMed2005

Intraductal tubular neoplasms of the pancreas: histogenesis and differentiation.

OBJECTIVES: Intraductal neoplasms of the pancreas are generally referred to as intraductal papillary mucin-producing neoplasms (IPMNs), according to the WHO classification system. Herein, we report that morphologic and immunohistochemical features of intraductal tubular carcinoma (ITC) are quite different from those of intraductal papillary mucinous carcinoma (IPMC). METHODS: We analyzed histogenesis and differentiation of ITC by light microscopy and immunohistochemistry. RESULTS: Histologically, ITC was characterized as an intraductal nodular appearances with a monotonous tubular growth pattern without papillary projection. ITC showed de novo-like appearance without sequential progression usually observed in IPMC, suggesting that ITC is a homogeneous neoplasm. Cuboidal tumor cells in ITC resembled normal pancreatic duct epithelia, and the characteristic growth pattern of ITC replaced that of normal pancreatic duct epithelium. Immunohistochemically, ITC cells were positive for MUC-1 on the apical side of the cell membrane. In contrast to ITC cells, IPMC cells were negative for MUC-1, and ductal adenocarcinoma cells were strongly positive for MUC-1, as was the stroma around the cancer. The immunohistochemical staining pattern of DUPAN-2 resembled that of MUC-1. Interestingly, localization of MUC-1 and DUPAN-2 staining in ITC cells was similar to that in normal pancreatic ductules. ITC cells were negative for MUC-2 and MUC-5AC. In contrast, most IPMC cells were positive for MUC-2 and MUC-5AC. CONCLUSION: Based on our histologic and immunohistochemical findings, the intraductal pancreatic neoplasm (IPN) can be classified into 2 groups: IPN with gastrointestinal differentiation and IPN with pancreatic duct differentiation. Our present data indicated that ITC cells may arise directly from duct epithelia without progression and possessed pancreatic duct differentiation. On the basis of our data, we suggest that classification of pancreatic neoplasms in the WHO and The Armed Forces Institute of Pathology (AFIP) systems should be reconsidered.

Adenocarcinoma↗
PubMed2004

Virological significance of low-level hepatitis B virus infection in patients with hepatitis C virus associated liver disease.

The clinical and virological significance of low-level viremia by hepatitis B virus (HBV) in hepatitis C virus (HCV)-infected patients remains unclear. HBV-DNA and HCV-RNA were, therefore, quantitatively analyzed in livers and sera from co-infected patients. HBV-DNA and HCV-RNA were quantitated using real-time detection of polymerase chain reaction (RTD-PCR), based on Taq-Man chemistry, in 220 non-HCV-infected healthy volunteers and 93 HCV-infected patients without detectable HBsAg. Serum HBV-DNA was detected in 4 (1.8%) of 220 non-HCV-infected healthy volunteers and 32 (34.4%) of 93 HCV-infected patients without detectable HBsAg. HCV-infected patients displayed higher frequency of HBV infection than healthy volunteers (P < 0.0001). Hepatocellular carcinoma (HCC) was more frequent among co-infected patients than among HCV mono-infected patients (P < 0.001). However, quantities of HBV-DNA in sera from co-infected patients were very low (8-19,000 copies/ml). HBV-DNA was detected in liver tissue from co-infected patients at 2-20 copies per 100 hepatocytes, accounting for 1/1,000 to 1/10,000 of HBsAg positive patients. In livers of patients with HCC and HCV or HBV mono-infection, the viruses existed predominantly in non-cancerous tissue, with levels 10- to 1,000-fold and 1- to 100-fold higher than in cancerous tissue, respectively. In contrast, patients co-infected with HCV and HBV displayed decreased HBV levels in non-cancerous tissue, but no change in cancerous tissue. These results indicate that low-level HBV infection exists in HCV-infected patients. HCC was more common among HCV/HBV co-infected patients than among HCV mono-infected patients. HCV might initiate hepatocarcinogenesis, but does not necessarily determine progression to HCC.

Adult↗
PubMed2004

Mucinous cystadenoma of the pancreas 17 years after excision of gallbladder because of a choledochal cyst.

A 56-year-old woman who had undergone excision of the gallbladder because of a choledochal cyst had a tumorous lesion of the pancreas identified by upper abdominal ultrasonography, but an operation was not carried out, because there was no apparent increase in the cystic mass and no elevation of serum tumor markers. In October 2001, she was admitted to our hospital to check for malignancy because of elevated levels of the tumor marker Dupan-2. Abdominal enhanced computed tomography and upper abdominal ultrasonography revealed a large multilocular cystic mass in the body to tail of the pancreas. Endoscopic retrograde cholangiopancreatography showed elongation of the common duct that communicates with the common bile duct and the main pancreatic duct, indicating an anomalous arrangement of the biliary and pancreatic duct system. No apparent communications between the cystic mass and the main pancreatic duct were observed. In January 2002, the patient underwent a spleen-preserving distal pancreatectomy, and histopathological and immunohistochemical examinations led to the diagnosis of pancreatic mucinous cystadenoma with ovarian-like stroma. The mucinous cystadenoma was detected 17 years after the operation for the choledochal cyst. To the best of our knowledge, no documented case reports of mucinous cystadenoma of the pancreas associated with a choledocal cyst have been reported to date. We present here the first case report of pancreatic mucinous cystadenoma occurring in the body to tail of the pancreas, associated with a choledocal cyst.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed2004

Histologic and immunohistochemical comparison of intraductal tubular carcinoma, intraductal papillary-mucinous carcinoma, and ductal adenocarcinoma of the pancreas.

OBJECTIVE: To analyze the differences between intraductal tubular carcinoma (ITC) and intraductal papillary-mucinous carcinoma (IPMC), we performed light microscopic and immunohistochemical analysis of 4 cases of ITC, 6 cases of IPMC, and 9 cases of ductal adenocarcinoma of the pancreas. METHODS AND RESULTS: Light microscopic examination showed no hyperplasia or adenoma around the carcinoma in ITC, and immunohistochemical analysis showed that the apical side of the cell membrane was positive for MUC-1 in almost all ITC cells. In contrast to ITC cells, all IPMC cells were negative for MUC-1 and ductal adenocarcinoma cells were strongly positive for MUC-1 in the cytoplasm and cell membrane. Immunohistochemical staining patterns of DUPAN-2 in ITC resembled those of MUC-1 in these cancers. ITC and IPMC cells were negative for carcinoembryonic antigen, but ductal adenocarcinoma cells were positive. There were no apparent differences in proliferative activity between ITC and IPMC, but ductal adenocarcinoma showed significantly greater activity than either ITC or IPMC. CONCLUSION: The PCNA-L.I of IPMC and ITC was lower and the cell atypia of them was more mild compared with those of ductal carcinoma, indicating that IPMC possess low-grade malignant potentials. However, we observed differences of growth patterns and mucous secretion between ITC and IPMC of the pancreas.

Adenocarcinoma↗
PubMed2004

[Liver failure].

Explore the source record for details and available documents.

Acute Disease↗
PubMed2004

[Allogeneic peripheral blood stem cell transplantation for a hepatitis B virus carrier with Epstein-Barr virus associated with hemophagocytic syndrome].

We report herein a 21-year-old hepatitis B virus (HBV) female carrier who developed persistent fever, lymphadenopathy and pancytopenia in September of 2000. Hemophagocytes were found in the bone marrow smears. Epstein-Barr virus (EBV) serology showed positive for VCA-IgG, IgM and EB-ER and negative for EBNA. The EBV genome was detected in the peripheral blood. The patient was diagnosed as having EBV-associated hemophagocytic syndrome (EBV-AHS) and received chemotherapy. Although she was treated with lamivudine three months after the initiation of chemotherapy, she developed severe hepatitis. She recovered from the hepatitis through a combination of plasma exchange, immunosuppressive and antiviral therapies. Because of the refractoriness of her EBV-AHS to chemotherapy, she received allogeneic peripheral blood stem cell transplantation (PBSCT) from her HLA-identical brother. Hepatitis B did not recur after the PBSCT under administration of lamivudine. The EBV genome in the peripheral blood disappeared soon after the PBSCT but it was revealed again after the initiation of prednisolone for the treatment of acute GVHD. A donor lymphocyte infusion (DLI) was given on day 169 and the EBV genome copy number in the peripheral blood gradually decreased and disappeared. Although the origin of the EBV-infected cells could not be determined as being from the host or donor, DLI was a useful treatment for the recurrence of EBV infection after allogeneic stem cell transplantation for EBV-AHS.

Adult↗
PubMed2003

Combined interferon alpha2b and cyclosporin A in the treatment of chronic hepatitis C: controlled trial.

BACKGROUND: Only 15% to 20% of patients with chronic hepatitis C have a sustained virological response to interferon monotherapy. The aim of the present study was to compare the efficacy and safety of interferon, in combination with oral cyclosporin A, with interferon monotherapy in the treatment of chronic hepatitis C. METHODS: We assigned 120 patients with chronic hepatitis C to receive the standard Japanese dose of interferon alpha2b alone for 24 weeks or that dose of interferon alpha2b in combination with cyclosporin A, at doses of 200 mg daily for the first 4 weeks and 100 mg daily for the following 20 weeks. All patients were assessed for drug safety, tolerance, and efficacy at the end of weeks 4, 12, 24, and 48. Efficacy was assessed by the disappearance of serum hepatitis C virus (HCV)-RNA by polymerase chain reaction and normalization of serum aminotransferase. The primary endpoint was a sustained virological response; i.e., sustained undetectable serum HCV RNA at 48 weeks. RESULTS: The sustained virological response rate was significantly higher in the combination therapy group (42/76) than in the monotherapy group (14/44; P = 0.01). The sustained biochemical response rate was also higher in the combination therapy group (46/76) than in the monotherapy group (17/44; P = 0.017). In patients with genotype 1 and high viral loads, the sustained virological response rate was markedly higher in the combination therapy group (16/38) than in the monotherapy group (1/21; P = 0.006). Side-effect profiles were similar in the two groups. CONCLUSIONS: In patients with chronic hepatitis C; combined interferon and cyclosporin A treatment was more effective than interferon monotherapy. The benefit was mostly achieved in patients with a high viral load and HCV genotype 1.

Alanine Transaminase↗