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Dive into the research topics where Masumi Ohhira is active.

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Featured researches published by Masumi Ohhira.


Journal of Gastroenterology | 2005

Usefulness of recombinant Em18-ELISA to evaluate efficacy of treatment in patients with alveolar echinococcosis.

Yoshinori Fujimoto; Akira Ito; Yuji Ishikawa; Mitsutaka Inoue; Yasuaki Suzuki; Masumi Ohhira; Takaaki Ohtake; Yutaka Kohgo

Alveolar echinococcosis (AE) is a rare parasitic disease caused by Echinococcus multicularis and most commonly involves the liver. Early diagnosis is essential to improve the prognosis of patients with AE of the liver. Em18, an 18-kD diagnostic antigen from Echinococcus multilocularis, is highly specific and sensitive to detect AE. We previously reported that an enzyme-linked immunosorbent assay (ELISA) system using a recombinant Em18 antigen (RecEm18) was highly useful in the differential serodiagnosis of AE. In this report, we present seven AE patients who showed dynamic changes in RecEm18-ELISA values in the course of long-term follow up of albendazole (ABZ) chemotherapy, and/or resections of the liver or bone metastasis. All seven AE patients revealed positive values, over the cutoff level, of the RecEm18-ELISA before the treatments. The values in six patients fell below the cutoff level after the treatments, but the value in a patient with recurrence never fell below the cutoff level, and increased again. From these results, it seems that the RecEm18-ELISA is useful to evaluate the efficacy of treatment and predict recurrence in patients with AE. RecEm18-ELISA may be an important examination for: (a) the mass screening of AE in Japan, (b) the confirmative diagnosis of AE prior to surgical and/or chemotherapeutic treatments,


Biochemical and Biophysical Research Communications | 2009

A Jak2 inhibitor, AG490, reverses lipin-1 suppression by TNF-α in 3T3-L1 adipocytes

Yoshihiro Tsuchiya; Nobuhiko Takahashi; Takayuki Yoshizaki; Sachie Tanno; Masumi Ohhira; Wataru Motomura; Satoshi Tanno; Kaoru Takakusaki; Yutaka Kohgo; Toshikatsu Okumura

Lipin-1 is a multifunctional metabolic regulator, involving in triacylglycerol and bioactive glycerolipids synthesis as an enzyme, transcriptional regulation as a coactivator, and adipogenesis. In obesity, adipose lipin-1 expression is decreased. Although lipin-1 is implicated in the pathogenesis of obesity, the mechanism is still not clear. Since TNF-alpha is deeply involved in the pathogenesis of obesity, insulin resistance, and diabetes, here we investigated the role of TNF-alpha on lipin-1 expression in adipocytes. Quantitative PCR studies showed that TNF-alpha suppressed both lipin-1A and -1B isoform expression in time- and dose-dependent manners in mature 3T3-L1 adpocytes. A Jak2 inhibitor, AG490, reversed the suppressive effect of TNF-alpha on both lipin-1A and -1B. In contrast, NF-kappaB, MAPKs, ceramide, and beta-catenin pathway tested were not involved in the mechanism. These results suggest that TNF-alpha could be involved in obesity-induced lipin-1 suppression in adipocytes and Jak2 may play an important role in the mechanism.


Journal of Gastroenterology | 2007

Lipopolysaccharide induces adipose differentiation-related protein expression and lipid accumulation in the liver through inhibition of fatty acid oxidation in mice

Masumi Ohhira; Wataru Motomura; Mitsuko Fukuda; Takayuki Yoshizaki; Nobuhiko Takahashi; Satoshi Tanno; Nobutaka Wakamiya; Yutaka Kohgo; Shima Kumei; Toshikatsu Okumura

BackgroundIn the present study, we examined the effect of lipopolysaccharide (LPS) on liver histopathology with special reference to lipid metabolism in mice.MethodsMice were injected with LPS intraperitoneally, and its effect on the liver was investigated pathologically and biochemically.ResultsOil-red O staining and adipose differentiation-related protein (ADRP) immunohistochemistry demonstrated that injection of LPS transiently induced lipid accumulation and ADRP expression in hepatocytes, especially around the portal vein. Microscopic observation revealed that lipid accumulation started 12 h after LPS injection. Time-course studies showed that LPS rapidly, within 2 h, decreased hepatic expression of nuclear hormone receptors, including peroxisome proliferator-activated receptor (PPAR) α. LPS inhibited the expression of PPARα-target genes involved in fatty acid oxidation in the liver such as those coding for enoyl-CoA hydratase, acyl-CoA dehydrogenase, and carnitine palmitoyl transferase-1, whereas LPS also suppressed the expression of genes related to fatty acid synthesis such as those for fatty acid synthase, stearoyl-CoA desaturase, and acetyl-CoA carboxylase α.ConclusionsLPS induces transient lipid accumulation and expression of ADRP in the liver through inhibition of fatty acid oxidation by downregulation of the PPARα-related transcriptional mechanism.


Journal of Gastroenterology | 1995

Changes in free radical-metabolizing enzymes and lipid peroxides in the liver of Long-Evans with cinnamon-like coat color rats.

Motoyuki Ohhira; Minoru Ono; Masumi Ohhira; Chihiro Sekiya; Masayoshi Namiki; Yoshinori Fujimoto; Minako Nagao; Michio Mori

We report changes in free radical-metabolizing enzymes and the increased generation of lipid peroxides associated with extreme metal accumulation in the liver of the Long-Evans with cinnamon-like coat color (LEC) rat, a new mutant strain displaying hereditary hepatitis and subsequent hepatocellular carcinoma. The activity of free radical-metabolizing enzymes and lipid peroxides, and the concentration of metal in the liver were determined sequentially after birth. Mn-superoxide dismutase activity significantly increased immediately after the onset of hepatitis in LEC rats, whereas no remarkable change was observed in control rats. Cu, Zn-superoxide dismutase activity in LEC rats was similar to that in control rats. Glutathione reductase activity increased, while glutathione peroxidase activity was lower in LEC rats than in control rats throughout the observation periods. Lipid peroxides, estimated by thiobarbituric acid reaction, also increased 4-to 5-fold immediately after the onset of hepatitis in LEC rats. Copper concentration was 30-to 50-fold higher in the liver of LEC rats than in control rats, and the iron content also increased significantly before and after the onset of hepatitis. These findings suggested that an oxidant injury generated by toxic metals could be one of the factors responsible for hepatocellular damage in this unique hereditary hepatitis.


Brain Research | 2015

Antinociceptive action against colonic distension by brain orexin in conscious rats.

Toshikatsu Okumura; Tsukasa Nozu; Shima Kumei; Kaoru Takakusaki; Saori Miyagishi; Masumi Ohhira

Increasing evidence has suggested that brain orexins are implicated in a wide variety of physiological functions. With regard to gastrointestinal functions, orexin-A acts centrally to regulate gastrointestinal functions such as gastric and pancreatic secretion, and gastrointestinal motility. Visceral sensation is also known as one of key gastrointestinal functions which are controlled by the central nervous system. Little is, however, known about a role of central orexin in visceral sensation. This study was therefore performed to clarify whether brain orexin may be involved in the process of visceral sensation. Visceral sensation was evaluated by colonic distension-induced abdominal withdrawal reflex (AWR) in conscious rats. Intracisternally administered orexin-A dose-dependently increased the threshold volume of colonic distension-induced AWR. In contrast, neither intraperitoneal injection of orexin-A nor intracisternal orexin-B altered the threshold volume. While intracisternal SB334867, an orexin 1 receptor antagonist, by itself failed to change the threshold volume, SB334867 injected centrally completely blocked the morphine-induced antinociceptive action against colonic distension. These results suggest for the first time that orexin-A specifically acts centrally in the brain to enhance antinociceptive response to colonic distension. We would furthermore suggest that endogenous orexin-A indeed mediates the antinociceptive effect of morphine on visceral sensation through the orexin 1 receptors. All these evidence might indicate that brain orexin plays a role in the pathophysiology of functional gastrointestinal disorders such as irritable bowel syndrome because visceral hypersensitivity of the gut is considered to play a vital role in the diseases.


Asia Pacific Family Medicine | 2010

Characteristics in patients with headache in an outpatient clinic in Japan

Toshikatsu Okumura; Sachie Tanno; Masumi Ohhira; Satoshi Tanno; Tsukasa Nozu

BackgroundLittle is known about the prevalence of primary and secondary headache in clinics in Japan. The aim of this study is to characterize patients with headache in an outpatient unit where primary care physicians are working in Japan.MethodsConsecutive outpatients who newly visited the Department of General Medicine, Asahikawa Medical College Hospital, Asahikawa, Japan between April 2005 and March 2009 were analyzed. Each parameter such as age, sex or diagnosis was investigated.ResultsOut of 4693 patients, 418 patients visited to our department because of headache. Primary headache was found in 167 patients (39.9%). The rate of tension-type headache (TTH) (30.8%) was highest, followed by migraine (9.1%). Approximately 3 times higher rate of migraine was observed in female patients when compared with male patients. In female patients, migraine was observed more frequently in younger patients. On the other hands, TTH was observed in almost all aged patients in males and females, and the rate of TTH peaks between the ages of 40 and 49 years in both sex. The present study also demonstrated that 8.4% of patients who chiefly complained of headache had been diagnosed as depression while 1.7% of remained patients had been diagnosed as depression, indicating 5-times higher rate of depression in patients with headache.ConclusionAll these results suggest that primary headache, especially TTH, is highly observed and depression should be considered in patients with headache in an outpatient clinic where primary care physicians are working in Japan.


European Journal of Radiology | 2003

Clinical utility of sequential imaging of hepatocellular carcinoma by contrast-enhanced power Doppler ultrasonograpy

Yasuaki Suzuki; Yoshinori Fujimoto; Yayoi Hosoki; Masako Suzuki; Shinobu Sakurai; Masumi Ohhira; Hiroyuki Saito; Yutaka Kohgo

The aim of this study was to investigate the clinical utility of sequential imaging of hepatocellular carcinoma (HCC) by contrast-enhanced power Doppler ultrasonograpy (CE-PDUS) to differentiate hepatocellular carcinoma from adenomatous hyperplasia (AH) and regenerated nodule (RN) and to predict the degree of differentiation of HCC. Fifty-one patients with 62 hepatic lesions including 33 moderately and poorly differentiated HCCs, 19 well-differentiated HCCs, seven AHs and three large RNs were examined by CE-PDUS. The imaging patterns during early arterial phase (tumor vessel image), late vascular phase (tumor perfusion image) and post-vascular phase (liver perfusion image) were classified as diffuse, basket, peripheral, central and no enhancement; as whole tumor, partial tumor and no enhancement; as whole tumor, partial tumor and no defect, respectively. The diffuse pattern in the tumor vessel image, the whole enhancement pattern in the tumor perfusion image and the whole defect pattern in the liver perfusion image were observed in moderately and poorly differentiated HCCs only. The basket pattern in the tumor vessel image and the partial defect pattern in the tumor perfusion image were observed in HCCs only. All AH/RNs showed no defect pattern in the liver perfusion image. The sequential imaging of HCC during early arterial, late vascular and post-vascular phases by CE-PDUS is clinically useful to differentiate HCC from AH/RN and to predict the degree of differentiation of HCC.


Journal of Gastroenterology | 1996

Primary biliary cirrhosis associated with idiopathic thrombocytopenic purpura.

Yusuke Mizukami; Motoyuki Ohhira; Akinori Matsumoto; Yukari Murazumi; Kazuhiko Murazumi; Hitoyoshi Ohia; Masumi Ohhira; Minoru Ono; Takayoshi Miyake; Isao Maekawa; Yutaka Kohgo

A case of primary biliary cirrhosis (PBC) associated with idiopathic thrombocytopenic purpura (ITP) is reported. The patient is a 59-year-old man. When he was 49 years old, he was diagnosed with ITP and received steroid therapy that successfully increased platelet numbers. However, the steroid therapy failed to normalize the elevated gamma-glutamyl transpeptidase. Ten years after this episode, he suffered from general itching and malaise and exhibited a gradual increase of serum biliary enzyme levels. Immunologically, IgM was increased and anti-mitochondrial antibody was positive. Histological findings of liver needle biopsy showed chronic non-suppurative destructive cholangitis, confirming the diagnosis of PBC. To date, very few PBC cases associated with ITP have been reported. Our case is the second one in Japan. PBC and ITP in our patient seemed to develop simultaneously, but the effect of steroid therapy on the two conditions was different. This result suggests that the autoimmune process may have been different in PBC and ITP in the present patient.


European Journal of Radiology | 2003

Usefulness of contrast-enhanced wide-band Doppler ultrasonograpy to diagnose alveolar echinococcosis of the liver and evaluate the effect of the treatment

Yasuaki Suzuki; Yoshinori Fujimoto; Yayoi Hosoki; Masako Suzuki; Mitsutaka Inoue; Shinobu Sakurai; Takaaki Ohtake; Masumi Ohhira; Hiroyuki Saito; Yutaka Kohgo

Alveolar echinococcosis is a rare parasitic disease caused by Echinococcus multicularis and most commonly involves the liver. Early diagnosis and accurate evaluation of the effect of the treatment are essential to improve the prognosis of patients with alveolar echinococcosis of the liver (AEL). The aim of this study was to demonstrate the characteristic imaging of AEL by contrast-enhanced Dynamic Flow (CE-DF) employing a wide-band Doppler technique for the diagnosis and the accurate evaluation of the effect of the treatment. Four patients with five AEL lesions before treatment or during medication were examined by CE-DF. All of the five AEL lesions examined by CE-DF revealed a defect with an irregular and distinct margin like a worm-eaten defect appearance, which was never observed on other hepatic lesions, in liver perfusion image during post-vascular phase. In addition, CE-DF made it possible to measure the size of AEL lesions accurately because the margin was detected distinctly. These data suggest that CE-DF is clinically useful for the diagnosis of AEL and the evaluation of the effect of the treatment.


Journal of Gastroenterology and Hepatology | 1998

Altered intrahepatic pathway of para-umbilical vein in portal hypertension

Motoyuki Ohhira; Hitoyoshi Ohta; Masumi Ohhira; Akinori Matsumoto; Takaaki Ohtake; Yoshinori Fujimoto; Kazuhiko Murazumi; Minoru Ono; Yutaka Kohgo

The object of this study was to determine the frequency and characteristics of altered paraumbilical vein in the hepatic parenchyma, developed from portal hypertension, using computed tomography (CT). Two hundred and ninety‐two patients who presented with portal hypertension from 1986 to 1996 were studied retrospectively. The pathway of the dilated para‐umbilical vein was demonstrated by contrast‐enhanced CT. Thirty‐one (11%) patients had a dilated para‐umbilical vein arising from the left portal vein into the falciform ligament. In 24 (77%) of these patients, the para‐umbilical vein followed the expected route, passing through the fissure of ligamentum teres hepatis. The remaining seven patients (23%) displayed the unusual pathway, with the vein arising from the left branch of the portal vein and passing into the hepatic parenchyma. In these seven patients, four had one collateral vein, and three patients had two collateral veins in the liver parenchyma. The dilated para‐umbilical vein frequently passes through the hepatic parenchyma in patients with portal hypertension.

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Tsukasa Nozu

Asahikawa Medical University

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Shima Kumei

Asahikawa Medical University

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Yutaka Kohgo

Asahikawa Medical College

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Motoyuki Ohhira

Asahikawa Medical College

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Yasuaki Suzuki

Asahikawa Medical College

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Kaoru Takakusaki

Asahikawa Medical University

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Minoru Ono

Asahikawa Medical College

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Satoshi Tanno

Asahikawa Medical College

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