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Dive into the research topics where Kazuya Takahama is active.

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Featured researches published by Kazuya Takahama.


Journal of Gastroenterology | 2002

Treatment of ulcerative colitis by feeding with germinated barley foodstuff: first report of a multicenter open control trial

Osamu Kanauchi; Toshihiro Suga; Masahiro Tochihara; Toshifumi Hibi; Makoto Naganuma; Hitoshi Asakura; Hiroshi Nakano; Kazuya Takahama; Yoshihide Fujiyama; Akira Andoh; Takashi Shimoyama; Nobuyuki Hida; Ken Haruma; Hideki Koga; Keiichi Mitsuyama; Michio Sata; Masanobu Fukuda; Atsushi Kojima; Tadao Bamba

Background. Germinated barley foodstuff (GBF) is a prebiotic foodstuff that effectively increases luminal butyrate production by stimulating the growth of protective bacteria. In the first pilot study, GBF has been shown to reduce both clinical activity and mucosal inflammation in ulcerative colitis (UC). The aim of this study was to investigate the efficacy of GBF in the treatment of UC in a multicenter open control trial. Methods. Eighteen patients with mildly to moderately active UC were divided into two groups using a random allocation protocol. The control group (n = 7) were given a baseline anti-inflammatory therapy for 4 weeks. In the GBF-treated group (n = 11), patients received 20–30 g GBF daily, together with the baseline treatment, for 4 weeks. The response to the treatments was evaluated clinically and endoscopically. Fecal micro-flora were also analyzed. Results. After 4 weeks of observation, the GBF-treated group showed a significant decrease in clinical activity index scores compared with the control group (P < 0.05). No side effects related to GBF were observed. GBF therapy increased fecal concentrations of Bifidobacterium and Eubacterium limosum. Conclusions. Oral GBF therapy may have the potency to reduce clinical activity of UC. We believe that these results support the use of GBF administration as a new adjunct therapy for UC.


BMC Gastroenterology | 2009

Selenoprotein S (SEPS1) gene -105G>A promoter polymorphism influences the susceptibility to gastric cancer in the Japanese population

Tomoyuki Shibata; Tomiyasu Arisawa; Tomomitsu Tahara; Masaaki Ohkubo; Daisuke Yoshioka; Naoko Maruyama; Hiroshi Fujita; Yoshio Kamiya; Masakatsu Nakamura; Mitsuo Nagasaka; Masami Iwata; Kazuya Takahama; Makoto Watanabe; Ichiro Hirata

BackgroundInflammation is a key factor in the process of carcinogenesis from chronic gastritis induced by Helicobacter pylori. Selenoprotein S (SEPS1) is involved in the control of the inflammatory response in the endoplasmic reticulum (ER). Recently the -105G>A polymorphism in the promoter of SEPS1 was shown to increase pro-inflammatory cytokine expression. We examined the association between this polymorphism and the risk of gastric cancer.MethodsWe took stomach biopsies during endoscopies of 268 Japanese gastric cancer patients (193 males and 75 females, average age 65.3), and 306 control patients (184 males and 122 females, average age 62.7) and extracted the DNA from the biopsy specimens. All subjects provided written informed consent. For the genotyping of the SEPS1 promoter polymorphism at position -105G>A, PCR-RFLP methods were used and the PCR products were digested with PspGI.Logistic-regression analysis was used to estimate odds ratios (OR) and 95% confidence intervals (CI), adjusting for age, sex, and H. pylori infection status.ResultsAmong cases, the distribution of genotypes was as follows: 88.4% were GG, 11.2% were GA, and 0.4% were AA. Among controls, the distribution was as follows: 92.5% were GG, 7.2% were GA, and 0.3% were AA. Among males, carrying the A allele was associated with an increased odds of gastric cancer, compared with the GG genotype (OR: 2.0, 95% CI 1.0–4.1, p = 0.07). Compared with the GG genotype, carrying the A allele was significantly associated with increased risks of intestinal type gastric cancer (OR: 2.0, 95%CI 1.0–3.9, p < 0.05) as well as of gastric cancer located in the middle third of the stomach (OR: 2.0, 95%CI 1.0–3.9, p < 0.05).ConclusionThe -105G>A promoter polymorphism of SEPS1 was associated with the intestinal type of gastric cancer. This polymorphism may influence the inflammatory conditions of gastric mucosa. Larger population-based studies are needed for clarifying the relation between inflammatory responses and SEPS1 polymorphism.


Digestion | 2007

Risk prediction of gastric cancer by analysis of aberrant DNA methylation in non-neoplastic gastric epithelium.

Tomomitsu Tahara; Tomiyasu Arisawa; Tomoyuki Shibata; Fangyu Wang; Masakatsu Nakamura; Mikijyu Sakata; Mitsuo Nagasaka; Tamaki Takagi; Yoshio Kamiya; Hiroshi Fujita; Shin Hasegawa; Masami Iwata; Kazuya Takahama; Makoto Watanabe; Ichiro Hirata; Hiroshi Nakano

Background: Aberrant DNA methylation is one of the major events in carcinogenesis. Promoter DNA methylation is also present in various non-neoplastic tissues including gastric epithelium as age-related phenomenon, suggesting that it occurs early in the process of tumorigenesis. Aim: We aimed to clarify the relationship of aberrant DNA methylation in non-neoplastic gastric epithelia with the risk of gastric cancer, Helicobactor pylori infection, and the degree of H. pylori-induced gastritis. Methods: 89 patients enrolled in this study. The status of aberrant DNA methylation was compared in two groups of patients: 43 cases with gastric cancer (mean age 65.9 years [29–91], F:M = 0.30, intestinal type [n = 25], diffuse type [n = 18]) and 46 age- and sex-matched patients without gastric cancer (peptic ulcer diseases [n = 11], gastritis [n = 35]) as a control group. Genomic DNA was extracted directly from non-neoplastic epithelia of antral biopsies obtained by endoscopy. The promoter methylation status of the p14 and p21 genes was determined by methylation-specific-polymerase chain reaction (MSP). The promoter methylation status of the p16 gene was quantified by digital densitographic analysis following MSP. The degree of gastritis in the antrum was assessed according to the updated Sydney system. The PG I/II ratio was calculated based on the data of serum PG I and PG II levels measured by radioimmunoassay. Results: In all 89 subjects, CpG island methylation was found in 25.8% for p14, 52.8% for p16, 1.1% for p21. Among non-cancer patients, the methylation frequency of the p14 gene was significantly higher in H. pylori-positive than in H. pylori-negative patients (38.5 vs. 10.0%, p = 0.03). The mean (± SD) methylation levels of the p16 gene in non-neoplastic gastric epithelium was significantly higher in gastric cancer cases both in all patients and in H. pylori-positive patients (0.45 ± 0.31 vs. 0.20 ± 0.17; p = 0.019, 0.45 ± 0.31 vs. 0.20 ± 0.17; p = 0.016, respectively). The methylation level of the p16 gene was also associated with the presence of intestinal-type gastric cancer (p = 0.017). The methylation level of the p16 gene was significantly higher in patients with intestinal metaplasia (IM) than those without (p = 0.04). Furthermore, the methylation level of the p16 gene was correlated with lower PG l/ll ratio (p = 0.04). The methylation of the p21gene was found in only 1 patient with gastric cancer. Conclusions: Our data suggest that promoter of the p14 gene may be one of the specific regions whose methylation is closely associated with H. pylori infection. Methylation levels of the p16 gene seem to be accumulated in the progression of gastric mucosal atrophy and IM, and thus may be associated with the presence of gastric cancer especially for intestinal-type histopathology.


The American Journal of Gastroenterology | 2008

Oral Spherical Adsorptive Carbon for the Treatment of Intractable Anal Fistulas in Crohn's Disease: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

Yoshihiro Fukuda; Masakazu Takazoe; Akira Sugita; Tadashi Kosaka; Fukunori Kinjo; Yoshimasa Otani; Hisao Fujii; Kazutaka Koganei; Kazuya Makiyama; Toshio Nakamura; Takeyasu Suda; S. Yamamoto; Toshifumi Ashida; Akira Majima; Norikazu Morita; Kazunari Murakami; Nobuhide Oshitani; Kazuya Takahama; Masahiro Tochihara; Tomoyuki Tsujikawa; Makoto M. Watanabe

OBJECTIVES:Anal fistulas are common in individuals with Crohns disease (CD). We sought to evaluate the efficacy of oral spherical adsorptive carbon (AST-120) (Kremezin®; Kureha Corporation, Tokyo, Japan) for the treatment of intractable anal fistulas in patients with CD.METHODS:In this multicenter, randomized, double-blind, placebo-controlled trial, patients with CD and at least one active anal fistula under treatment were assigned to receive either AST-120 or placebo for 8 wk. Improvement was defined as a reduction of 50% or more from baseline in the number of draining fistulas observed at both 4 and 8 wk. Remission was defined by closure of all draining fistulas at both 4 and 8 wk. The Perianal Disease Activity Index (PDAI) and Crohns Disease Activity Index (CDAI) were also assessed.RESULTS:In total, 62 patients were randomized, of whom 57 received AST-120 (N = 27) or placebo (N = 30). The improvement rate in the AST-120 group (37.0%) was significantly greater than that in the placebo group (10.0%) (P= 0.025). The corresponding remission rates were 29.6% and 6.7%, respectively (P= 0.035). PDAI significantly improved at both 4 and 8 wk with AST-120, compared to placebo (P= 0.004 and P= 0.005, respectively). CDAI was also significantly improved at both 4 and 8 wk in the AST-120 group, compared to the placebo group (P= 0.007 and P= 0.001, respectively). AST-120 treatment was well tolerated and no life-threatening adverse events were observed.CONCLUSION:AST-120 is useful for the control of intractable anal fistulas in CD patients.


Journal of Gastroenterology and Hepatology | 2007

Genetic polymorphisms of CD14 and Toll-like receptor-2 (TLR2) in patients with ulcerative colitis

Fang-Yu Wang; Tomomitsu Tahara; Tomiyasu Arisawa; Tomoyuki Shibata; Masakatsu Nakamura; Hiroshi Fujita; Masami Iwata; Yoshio Kamiya; Mitsuo Nagasaka; Kazuya Takahama; Makoto Watanabe; Ichiro Hirata; Hiroshi Nakano

Background and Aim:  Ulcerative colitis (UC) is a multifactorial disease resulting from a complex interaction of genetic and environmental factors. Identifying genetic variants that alter the innate immune response is highly relevant to understanding the pathogenesis of UC. The aim of this study was to investigate the association between CD14 and Toll‐like receptor‐2 (TLR2) genetic polymorphisms and chronic UC in Japanese patients.


Journal of Gastroenterology and Hepatology | 2006

Effect of concurrent elemental diet on infliximab treatment for Crohn’s disease

Torao Tanaka; Kazuya Takahama; Tomomi Kimura; Tamaki Mizuno; Mitsuo Nagasaka; Katsumi Iwata; Hiroshi Nakano; Masaaki Muramatsu; Masakazu Takazoe

Background:  Infliximab and elemental diet (ED) have been shown to be effective in the management of Crohn’s disease. However, few experiences have been reported regarding their combination therapy. The aim of the present study was to investigate the efficacy and safety of infliximab in Japanese patients, the first such study in Asia, as well as the effect of concomitant ED.


European Journal of Gastroenterology & Hepatology | 2009

Increased number of methylated CpG islands correlates with Helicobacter pylori infection, histological and serological severity of chronic gastritis.

Tomomitsu Tahara; Tomiyasu Arisawa; Tomoyuki Shibata; Masakatsu Nakamura; Daisuke Yoshioka; Masaaki Okubo; Naoko Maruyama; Toshiaki Kamano; Yoshio Kamiya; Hiroshi Fujita; Yoshihito Nakagawa; Mitsuo Nagasaka; Masami Iwata; Kazuya Takahama; Makoto M. Watanabe; Hiromi Yamashita

Background Promoter hypermethylation of tumor suppressor genes is one of the major events in gastric carcinogenesis. Promoter hypermethylation is also present in non-neoplastic gastric epithelium as age-related phenomenon and some reports suggest the potential association between promoter hypermethylation and Helicobacter pylori infection. Here, we examined whether methylation of multiple promoter CpG islands would occur by H. pylori infection and correlate with histological or serological severity of chronic gastritis. Methods One hundred and ninety-one gastric mucosa samples were obtained by endoscopy. The promoter methylation status of the p14, p16, DAP-kinase and CDH1 genes were determined by methylation-specific-polymerase chain reaction. The degree of gastritis in the antrum was assessed according to the updated Sydney system in 150 participants. The pepsinogen (PG) I/II ratio was calculated based on the data of serum PG I and PG II levels measured by radioimmunoassay in 54 selected cases. Results CpG island methylation was found in 32.5% for p14, 35.1% for p16, 43.5% for DAP-kinase and 36.1% for CDH1, whereas non, 1, 2, 3, and all methylation of four promoter CpG sites were present in 46 (24.1%), 59 (30.9%), 46 (24.1%), 30 (15.7%), and 10 (5.2%) participants, respectively. A strong association between the increased number of methylated CpG islands and H. pylori infection was observed (P<0.0001). An increased number of methylated CpG islands was also associated with severity of neutrophil infiltration (P<0.0001), mononuclear cell infiltration (P<0.0001) and atrophy (P=0.0021) in all, and severity of neutrophil infiltration (P=0.0177) and mononuclear cell infiltration (P=0.0004) in H. pylori-positive participants. An increased number of methylated CpG islands correlated with lower PG I/II ratio in all (P=0.0105) and H. pylori-infected participants (P=0.074). Conclusion Multiple promoter CpG islands would be methylated by H. pylori infection, and an increased number of methylated CpG sites correlate with histological and serological severity of chronic gastritis.


Abdominal Imaging | 1992

Intestinal tuberculosis: Findings on double-contrast barium enema

Hiroshi Nakano; Edgar Jaramillo; Makoto Watanabe; Ikuro Miyachi; Kazuya Takahama; Madoka Itoh

Seven cases of intestinal tuberculosis in an active stage were studied by the double-contrast barium enema (DCBE) method. Formerly, diagnosis of intestinal tuberculosis in the early stage by single-contrast barium enema (SCBE) and barium meals was based on functional phenomena, such as spasm and hypermotility of the ileocecal region. Presently, this can be better accomplished by DCBE. DCBE enables the detection of shallow ulcers with their characteristic elevated margins. These ulcers are frequently slim and transversally oriented. Confluence of ulcers may create whole girdle ulcers or affecte entire segments. In more advanced stages, characteristic deformities, also evident by SCBE, such as symmetrical annular stenoses, shortening, retraction, pouch formation, and the frequently observed pathology of the ileocecal valve and the cecal region, acquire a new dimension with DCBE.


Journal of Clinical Biochemistry and Nutrition | 2008

A Genetic Variant of the CD14 C-159T in Patients with Functional Dyspepsia (FD) in Japanese Subjects.

Tomomitsu Tahara; Tomiyasu Arisawa; Tomoyuki Shibata; Masakatsu Nakamura; Fangyu Wang; Daisuke Yoshioka; Masaaki Okubo; Naoko Maruyama; Yoshio Kamiya; Masahiko Nakamura; Hiroshi Fujita; Mitsuo Nagasaka; Masami Iwata; Kazuya Takahama; Makoto Watanabe; Ichiro Hirata; Hiroshi Nakano

Inflammatory changes in the gastric mucosa are commonly observed in Japanese patients with functional dyspepsia (FD). However, detailed data regarding the relationship between the genetic regulatory factors of inflammation and FD are not available. CD14 is an important mediator of the inflammatory response in the first line of host defense by recognition of Lipopolysaccharide (LPS). We aimed to investigate the association between CD14 promoter C-159T polymorphism and FD in a Japanese population. 108 patients with FD and 99 non-dyspeptic subjects enrolled in this study. Dyspeptic symptoms were divided according to Rome III criteria. CD14 gene C-159T polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism. In the non-dyspeptics, the CD14 genotype distribution was 28CC (28.3%), 51CT (51.5%), 21TT (21.2%). Meanwhile, the CD14 genotype distribution in FD was 31CC (28.4%), 56CT (51.4%), 22TT (20.2%). The genotype distribution was not significantly different. There was no significant difference between two groups in the genotype distribution. We did not found any association between CD14 genotypes and dyspeptic patients in different gender and Helicobacter pylori infection status. No significant association was also found between CD14 polymorphism and any of different subtypes of FD according to Rome III while there was a weak correlation between TT genotype and PDS in male subjects (TT vs others, OR = 3.18, 95% CI = 0.98−10.26, p = 0.06). In conclusion, our results suggest that CD14 polymorphism is unlikely to associate with susceptibility of dyspeptic symptoms. The role of inflammation related-gene polymorphisms to the development of dyspepsia needs to further evaluation.


Hepato-gastroenterology | 2012

Role of heat-shock protein (HSP) 70-2 genotype in peptic ulcer in Japanese population.

Tomomitsu Tahara; Tomiyasu Arisawa; Tomoyuki Shibata; Hiromi Yamashita; Masakatsu Nakamura; Daisuke Yoshioka; Masaaki Okubo; Naoko Maruyama; Toshiaki Kamano; Yoshio Kamiya; Hiroshi Fujita; Nakagawa Y; Mitsuo Nagasaka; Masami Iwata; Kazuya Takahama; Makoto M. Watanabe; Hiroshi Nakano

BACKGROUND/AIMS There have been reports showing the protective role of inducible heat-shock protein (HSP) 70 in gastric epithelial cells. An A to G transition at the 1267 position HSP70-2 gene has been shown to be associated with a different level of HSP70 mRNA expression. We aimed to clarify the effect of HSP70-2 polymorphism on the risk of peptic ulcer diseases in a Japanese population. METHODOLOGY A total of 519 subjects participated in this study. All subjects underwent upper gastroscopy. Restriction fragment length polymorphism analysis was performed for polymorphisms at 1267 of HSP70-2 gene in all the subjects. RESULTS After gastroscopy, 109, 53 and 357 subjects were diagnosed as gastric ulcer, duodenal ulcer and non-ulcer subjects, respectively. Although, there were no significant differences of HSP70-2 genotype distributions among nonulcer subjects, overall ulcer, gastric and duodenal ulcers when the subjects were divided into two groups according to age distribution, logistic regression analysis showed that the BB genotype increased the risk of duodenal ulcer in subjects 60 years and older. (Gender, status of H. pylori infection and NSAID use adjusted OR=3.12, 95%CI=1.33-7.35, p=0.009). CONCLUSIONS It appears that polymorphism of HSP70-2 gene is not directly associated with the susceptibility to peptic ulcer diseases but BB genotype is associated with an increased risk of duodenal ulcer in older subjects in the Japanese population.

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Masami Iwata

Fujita Health University

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Yoshio Kamiya

Fujita Health University

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Naoko Maruyama

Fujita Health University

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Masaaki Okubo

Osaka Prefecture University

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