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Dive into the research topics where Tomoyuki Nomura is active.

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Featured researches published by Tomoyuki Nomura.


Gastrointestinal Endoscopy | 2004

Cholangiography can discriminate sclerosing cholangitis with autoimmune pancreatitis from primary sclerosing cholangitis

Takahiro Nakazawa; Hirotaka Ohara; Hitoshi Sano; Shigeru Aoki; Shinya Kobayashi; Tetsu Okamoto; Hideto Imai; Tomoyuki Nomura; Takashi Joh; Makoto Itoh

BACKGROUND Sclerosing cholangitis with autoimmune pancreatitis has a cholangiographic appearance that is similar to that of primary sclerosing cholangitis, but only the former responds well to corticosteroid therapy. It, therefore, is necessary to distinguish between these two diseases. Cholangiography is the reference standard for the diagnosis of primary sclerosing cholangitis. The present study compared the characteristic findings for these two types of sclerosing cholangitis. METHODS Cholangiograms from patients with primary sclerosing cholangitis (n = 29) and sclerosing cholangitis with autoimmune pancreatitis (n = 26) were studied with regard to length and region of stricture formation, and other characteristic findings. RESULTS Band-like stricture, beaded or pruned-tree appearance, and diverticulum-like formation were significantly more frequent in primary sclerosing cholangitis. In contrast, segmental stricture, long stricture with prestenotic dilatation and stricture of the distal common bile duct were significantly more common in sclerosing cholangitis with autoimmune pancreatitis. Discriminant analysis based on these findings correctly identified 27 of 28 patients with primary sclerosing cholangitis and 25 of 26 patients with sclerosing cholangitis with autoimmune pancreatitis. It also identified a patient with an incorrect diagnosis of primary sclerosing cholangitis who proved, on review of a surgical specimen, to have findings consistent with lymphoplasmacytic sclerosing cholangitis. CONCLUSIONS Characteristic cholangiographic features allow discrimination of sclerosing cholangitis with autoimmune pancreatitis and lymphoplasmacytic sclerosing cholangitis without pancreatitis from primary sclerosing cholangitis.


Journal of Gastroenterology | 2001

Th1/Th2 cytokine profiles and their relationship to clinical features in patients with chronic hepatitis C virus infection

Satoshi Sobue; Tomoyuki Nomura; Tetsuya Ishikawa; Satomi Ito; Katsuhisa Saso; Hirotaka Ohara; Takashi Joh; Makoto Itoh; Shinichi Kakumu

Purpose. An imbalance in helper T-cell type 1 (Th1) and type 2 (Th2) cytokines is suggested to play an important role in the pathogenesis of chronic viral infections, but this issue is not resolved in patients with hepatitis C virus (HCV) infection. The aim of this study was to clarify the relationship between the balance of Th1 and Th2 cytokines and liver damage. Methods. We investigated cytokine levels in the peripheral blood and liver tissue of patients with chronic HCV infection (n = 59) by three different methods; we used flow cytometry to detect intracellular cytokines, and we measured cytokine titers in sera and in the supernatants of lymphocyte cultures with enzyme-linked immunosorbent assays (ELISAs). Results. In both CD4+ and CD8+ cells, interferon (IFN) γ-producing cell populations increased, while there was no difference in interleukin (IL)-10 production, indicating a shift to a Th1 cytokine profile with the progression of liver disease. With respect to the ratio of IFN-γ to IL-10, a correlation was found in CD4+ cells between peripheral blood and liver tissue (r = 0.98; P = 0.0011). Th1 cytokine was predominant in intrahepatic CD4+ cells, while it was predominant in peripheral blood CD8+ cells. Conclusions. These findings indicate a correlation between dominant Th1 response and disease activity and progression. In addition, we suggest that intrahepatic CD4+ T cells play a pathogenetic role in the hepatic injury of HCV infection.


The American Journal of Gastroenterology | 1999

Standards for selecting percutaneous ethanol injection therapy or percutaneous microwave coagulation therapy for solitary small hepatocellular carcinoma: consideration of local recurrence

Hideo Horigome; Tomoyuki Nomura; Katsuhisa Saso; Makoto Itoh

OBJECTIVES:Percutaneous ethanol injection therapy (PEIT) and percutaneous microwave coagulation therapy (PMCT) are effective treatments for small hepatocellular carcinoma (HCC). There are no clear standards, however, for the selection of PEIT or PMCT. We determined standards based on local recurrence.METHODS:The subjects were 88 patients with solitary HCC measuring ≤30 mm in diameter, who were treated by PEIT (n = 45) or PMCT (n = 43) and judged to be cured using computerized tomography (CT) with contrast medium after treatment. Patient characteristics, including age, gender, viral markers, Child-Pugh classification, tumor size, tumor cell differentiation, and serum α-fetoprotein (AFP) concentration we analyzed, and the factors influencing the local recurrence in the PEIT and PMCT groups were determined, using univariate and multivariate analysis.RESULTS:Univariate analysis indicated that tumor cell differentiation and serum AFP concentration influenced local recurrence in the PEIT group, and tumor size did so in the PMCT group. Multivariate analysis revealed that tumor cell differentiation influenced local recurrence in the PEIT group, and tumor size did so in the PMCT group. PEIT was effective for treating well-differentiated HCC, and PMCT was effective for treating HCC measuring ≤15 mm in diameter. PMCT was superior to PEIT for treating patients with HCC measuring ≤15 mm in diameter. In such cases with well-differentiated HCC, PEIT was as effective as PMCT.CONCLUSIONS:The selection of PEIT or PMCT to treat patients with HCC should be based on tumor size and cell differentiation.


Journal of Gastroenterology and Hepatology | 2002

Limitations of imaging diagnosis for small hepatocellular carcinoma: Comparison with histological findings

Hideo Horigome; Tomoyuki Nomura; Katsuhisa Saso; Makoto Itoh; Takashi Joh; Hirotaka Ohara

Background and Aims : The purpose of this study was to clarify the value and limitation of imaging modalities for diagnosing small hepatocellular carcinoma (HCC).


Journal of Gastroenterology | 2003

Intracystic hemorrhage of a simple liver cyst mimicking a biliary cystadenocarcinoma

Yasuhiro Kitajima; Yasutaka Okayama; Masaaki Hirai; Kazuki Hayashi; Hideto Imai; Tetsu Okamoto; Shigeru Aoki; Shinji Akita; Kazuo Gotoh; Hirotaka Ohara; Tomoyuki Nomura; Takashi Joh; Yoshifumi Yokoyama; Makoto Itoh

Simple liver cysts are rarely complicated by intracystic hemorrhage. We encountered a case of simple liver cyst that was morphologically similar to biliary cystadenocarcinoma, which was complicated by asymptomatic intracystic hemorrhage and successfully treated by right lobectomy. A large cystic lesion of the liver was detected in a 57-year-old woman during a mass screening health check. Abdominal ultrasonography (US) revealed that the cystic lesion, containing many hyperechoic papillary structures, occupied almost the entire region of the right hepatic lobe. In addition, a round mural nodule, measuring approximately 5 cm in diameter, was detected in the cystic wall. Abdominal computed tomography (CT) revealed that the inner part of the cystic lesion showed homogeneous low density, but CT did not show the round nodule detected by US. On T1-weighted sequence of magnetic resonance imaging (MRI), the lesion showed homogeneous high signals, together with a low-signal tumorous lesion in the cystic wall. T2-weighted sequence of MRI showed unhomogeneous high signals, together with high signals in the tumorous part. These findings did not exclude the possibility of a malignant cystic tumor, such as biliary cystadenocarcinoma. Therefore, right lobectomy was performed. Histological examinations of resected tissue specimens revealed that the lesion was a liver cyst containing a large amount of blood clot, and that the tumorous lesion detected by US and MRI was a large mass of blood clot which was partly liquefied. This case indicates the diagnostic importance of the morphological discordance between CT and US or MRI findings for liver cyst containing a large amount of blood clot.


Vaccine | 2002

Immune responses in mice to intranasal and intracutaneous administration of a DNA vaccine encoding Helicobacter pylori-catalase

Masayuki Miyashita; Takashi Joh; Katsushi Watanabe; Isami Todoroki; Kyoji Seno; Hirotaka Ohara; Tomoyuki Nomura; Mitsuki Miyata; Kunio Kasugai; Kunio Tochikubo; Makoto Itoh; Masakazu Nitta

We previously reported that the intracutaneous injection of DNA vaccines encoding Helicobacter pylori heat shock proteins elicited specific immune responses, and led to reduced infection in mice. In this study, we constructed DNA vaccine encoding H. pylori-catalase (pcDNA3.1-kat) and investigated the immune responses to intranasal and intracutaneous administration of pcDNA3.1-kat. C57/BL6 mice were immunized intracutaneously with 10 microg of pcDNA3.1-kat or intranasally with 50 microg of pcDNA3.1-kat. Catalase-specific IgG antibody was detected in the sera of intranasal and intracutaneous immunized mice. Both intranasal and intracutaneous immunized mice were significantly protected from colonization by H. pylori and had significantly reduced degrees of gastritis. These results demonstrate that DNA vaccine encoding H. pylori-catalase can induce an immune response against H. pylori, and that intranasal immunization works as well as intracutaneous immunization.


Journal of Gastroenterology and Hepatology | 2005

Intrahepatic biliary papilloma morphologically similar to biliary cystadenoma

Shigeru Aoki; Yasutaka Okayama; Yasuhiro Kitajima; Kazuki Hayashi; Hideto Imai; Tetsu Okamoto; Shinji Akita; Kazuo Gotoh; Hirotaka Ohara; Tomoyuki Nomura; Takashi Joh; Yoshifumi Yokoyama; Makoto Itoh

Abstract  A 37‐year‐old man presented complaining of epigastralgia. Abdominal ultrasonography revealed the presence of a papillary tumor (9 mm in diameter) in the cystic lesion (18 mm in diameter) in hepatic segment 4, which was accompanied by mild intrahepatic bile duct dilatation. Although abdominal computed tomography also showed the cystic lesion, it did not show papillary tumors inside the lesion. Endoscopic retrograde cholangiography showed the communication between the cystic lesion and the left hepatic duct. In addition, mucus was observed in the common bile duct. When transpapillary intraductal ultrasonography was performed through the left hepatic duct using a fine ultrasonic probe, a hyperechoic papillary and lobulated tumor was clearly shown in the cystic lesion. The wall of the cyst was smooth and there was no sign of tumor infiltration. Based on these findings, biliary cystadenoma was diagnosed and an extended left lobectomy was carried out. However, pathological findings postoperatively revealed that the lesion was a localized biliary papilloma, developing and extending to the intrahepatic duct. This case is rare and there have been no published reports describing a biliary papilloma morphologically similar to biliary cystadenoma.


Pancreas | 2000

Apoptosis of acinar cells is involved in chronic pancreatitis in Wbn/Kob rats: role of glucocorticoids.

Takashi Hashimoto; Tamaki Yamada; Takio Yokoi; Hitoshi Sano; Hakuji Ando; Takahiro Nakazawa; Hirotaka Ohara; Tomoyuki Nomura; Takashi Joh; Makoto Itoh

The involvement of pancreatic acinar cell apoptosis and its relation to glucocorticoid exposure were investigated in spontaneously occurring chronic pancreatitis in male Wistar Bonn/Kobori (WBN/Kob) rats. Although most lobules were not inflamed in 10-week-old WBN/Kob, increased apoptosis of pancreatic acinar cells, confirmed by TUNEL staining was focally observed (0.10 ± 0.10 vs. 0.05 ± 0.10/field in 10-week Wistar rats). Localized hemorrhagic lesions and brown foci in the splenic lobes were apparent, with significant decrease in pancreas weight in 20-week WBN/Kob rats along with marked apoptosis (1.95 ± 0.31 vs. 0.07 ± 0.04/field in 20-week Wistar rats). Electron microscopy revealed apoptotic bodies to be present in acinar cells. Pancreatic myeloperoxidase activities, indirect indices of granulocyte infiltration, as well as histologic scores were significantly increased at 15 and 20 weeks, and endogenous corticosterone levels were significantly decreased at 10, 15, and 20 weeks as compared with values for age-matched Wistar rats. Prednisolone in the drinking water (0.01 mg/mL; calculated dose, 1.03 ± 0.03 mg/kg/d) for 10 weeks significantly attenuated increases in numbers of apoptotic acinar cells and pancreatic myeloperoxidase activities and tended to reduce the histologic scores in 20-week WBN/Kob rats as compared with the vehicle group. In summary, (a) apoptosis of pancreatic acinar cells is involved in chronic pancreatitis, (b) endogenous corticosterone is decreased, and (c) prednisolone treatment attenuates both apoptosis of pancreatic acinar cells and chronic pancreatitis in male WBN/Kob rats. We conclude that apoptosis of acinar cells related to decreased corticosterone may be a trigger of chronic pancreatitis in this model.


Journal of Gastroenterology | 2003

Exophytic pedunculated gastrointestinal stromal tumor with remarkable cystic change

Itaru Naitoh; Yasutaka Okayama; Masaaki Hirai; Yasuhiro Kitajima; Kazuki Hayashi; Tetsu Okamoto; Shinji Akita; Kazuo Gotoh; Mutsue Mizusima; Hitoshi Sano; Hirotaka Ohara; Tomoyuki Nomura; Takashi Joh; Yoshifumi Yokoyama; Makoto Itoh

A 59-year-old man with bloody stools, and previously diagnosed with sigmoid colon carcinoma, visited our hospital. Preoperative abdominal ultrasonography (US) showed another tumor, with an uneven irregular surface, measuring about 9 × 5 cm, below the left hypochondrium. The tumor consisted of several cysts. Abdominal computed tomography (CT) showed a multicystic tumor attached to the stomach, and its septum and marginal region were intensely stained on contrast imaging. On magnetic resonance imaging (MRI), low and markedly high signals were revealed in the tumor on T1-weighted and T2-weighted sequences, respectively. Contrast imaging of the upper digestive tract showed extramural compression of the greater curvature of the antral stomach by the tumor. The tumor was partially imaged by endoscopic ultrasonography (EUS), but continuity to the stomach was not confirmed. On abdominal angiography, the tumor was slightly stained via the gastroepiploic arteries. Surgical treatment was performed to excise both the gastric tumor and the sigmoid colon carcinoma. The gastric tumor was removed with gastric wall tissue where the tumor was attached to a 2-cm pedicle. It was multicystic, contained watery fluid, and had a smooth outer surface. Histologically, the tumor consisted of multiple irregular cysts without epithelial lining, and solid epitheloid cell nests in between. The tumor cells had clear or eosinophilic cytoplasm and round nuclei. No mitotic figures were seen. The tumor cells in the pedicle were connected with the muscularis propriae of the stomach. Immunohistochemistry showed c-kit-positive, CD34-positive smooth muscle actin (SMA)-negative, and S-100-negative staining of tumor cells. The final diagnosis was gastrointestinal stromal tumor (GIST).


Microbiology and Immunology | 1999

Arginine Carboxypeptidase (CPR) in Human Plasma Determined with Sandwich ELISA

Xiaoyan Guo; Akihiro Morioka; Yoko Kaneko; Noriko Okada; Kyoko Obata; Tomoyuki Nomura; William Campbell; Hidechika Okada

There are two types of carboxypeptidases present in human blood, carboxypeptidase N (CPN) and arginine carboxypeptidase (CPR). CPR is generated during coagulation from a precursor (proCPR) which can be converted to the active form by trypsin in vitro. Since it is difficult to distinguish the two types of carboxypeptidases in human blood by the measurement of enzyme activity, we established a quantitative sandwich ELISA by which CPR can be quantitated. The amount of CPR in plasma, fresh serum and heated serum were essentially the same. Therefore the ELISA assay does not distinguish proCPR, activated CPR and inactivated CPR. With the ELISA method, CPR was quantitated in plasma from fifty patients with rheumatoid arthritis and eleven patients with severe hepatitis as well as healthy individuals. The amount of CPR in plasma obtained from patients with rheumatoid arthritis was not found to be lower than that of normal subjects. Furthermore, the patients who suffered severe hepatitis and had very low levels of CPR‐total were fatal. This suggests that a decrease of CPR level might be a good indication of a patients prognosis to death by hepatitis.

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Makoto Itoh

Nagoya City University

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Takashi Joh

Nagoya City University

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