Mitsuki Miyata

Aichi Medical University, Masaki-chō, Ehime, Japan

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Publications (6)14.44 Total impact

  • Article: Therapeutic efficacy of infliximab on patients with short duration of Crohn's disease: a Japanese multicenter survey.
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    ABSTRACT: This study was designed to evaluate the efficacy of infliximab in patients with Crohn's disease of durations less than one year. Two nationwide surveys of 35 Japanese institutions majoring in inflammatory bowel disease identified 41 patients with active Crohn's disease who were treated by infliximab within 12 months after the diagnosis (E-group) and 97 patients treated later during their clinical course (L-group). Clinical features, responses to infliximab, and accompanying medications were compared between the two groups. A decrease in Crohn's disease activity index > or = 70 or the index < 150 two weeks after infliximab was regarded to be efficacious. The age was younger (24 vs. 33 years, median, P < 0.0001) and intestinal stricture (12 vs. 49 percent, P < 0.0001), internal fistula (0 vs. 26 percent, P = 0.0003), and previous intestinal resection (7 vs. 57 percent, P < 0.0001) were less frequent in the E-group than in the L-group. The efficacy of infliximab was different between the two groups with a significantly higher value in the E-group than in the L-group (90 vs. 61 percent, P = 0.0012). A multivariate logistic regression analysis revealed nonstricturing intestinal lesion to be a significant factor related to the efficacy of infliximab. Infliximab is more efficacious in Crohn's disease with short duration, probably because of less frequent stenosis.
    Diseases of the Colon & Rectum 07/2008; 51(6):916-23. · 3.13 Impact Factor
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    Article: Successful treatment of severe pouchitis with rebamipide refractory to antibiotics and corticosteroids: a case report.
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    ABSTRACT: The antibiotics, metronidazole and ciprofloxacin, are the first-line treatment for pouchitis. Patients who do not respond to antibiotics or conventional medications represent a major challenge to therapy. In this report, we have described a successful treatment of severe refractory pouchitis with a novel agent, rebamipide, known to promote epithelial cell regeneration and angiogenesis. A 27-year-old male with ileo-anal pouch surgery presented with worsening anal pain, diarrhea, and abdominal pain. The patient was diagnosed to have pouchitis and was given metronidazole together with betamethasone enema (3.95 mg/dose). However, despite this intensive therapy, the patient did not improve. On endoscopy, ulceration and inflammation were seen in the ileal pouch together with contact bleeding and mucous discharge. The patient was treated with rebamipide enema (150 mg/dose) twice a day for 8 wk without additional drug therapy. Two weeks after the rebamipide therapy, stool frequency started to decrease and fecal hemoglobin became negative at the 4th wk. At the end of the therapy, endoscopy revealed that ulcers in the ileal pouch had healed with no obvious inflammation. The effect of rebamipide enema was dramatic and was maintained throughout the 11-mo follow-up. The patient continued to be in remission. No adverse effects were observed during the treatment or the follow-up period. The sustained response seen in this case with severe and refractory pouchitis indicates that agents, which promote epithelial cell growth, angiogenesis and mucosal tissue regeneration, are potential therapeutic agents for the treatment of refractory colorectal lesions.
    World Journal of Gastroenterology 02/2006; 12(4):656-8. · 2.47 Impact Factor
  • Article: Rebamipide enemas-new effective treatment for patients with corticosteroid dependent or resistant ulcerative colitis.
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    ABSTRACT: In this study we investigated the effect of rebamipide enema in patients with steroid-resistant and/or dependent ulcerative colitis. Rebamipide enemas were administered twice daily for a 12-week period; this treatment was further continued longer in patients who requested this. Disease activity index as reflecting the clinical condition and endoscopic index with histological grading were determined before and after the treatment period. Nine of 11 (81.8%) patients on 12-week treatment with rebamipide approved and were classified as colitis in remission. Moreover, seven of 11 patients requested long-term medication, the longest medication term being 80 weeks. These results medicated that rebamipide enemas may be effective in patients with steroid-resistant and/or dependent ulcerative colitis.
    Digestive Diseases and Sciences 11/2005; 50 Suppl 1:S119-23. · 2.12 Impact Factor
  • Article: ASSESSMENT OF MISS AND INCIDENCE RATES OF NEOPLASTIC POLYPS AT COLONOSCOPY
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    ABSTRACT: Background:  The incidence rate after a colonoscopic polypectomy includes the true incidence rate of new polyp formation and miss rate of polyps at the initial colonoscopy. It is therefore important to assess accurate incidence rates of polyps as well as those of missing polyps with colocoscopy.Methods:  Six hundred and eighty-eight patients who underwent total colonoscopy twice within 30 days were investigated to determine the miss rates of neoplastic polyps under colonoscopy. The cumulative incidence rates of neoplasm were evaluated by the Kaplan-Meier method in another series of investigations on 864 patients who underwent surveillance total colonoscopy over 31 days.Results:  In 157 (22.8%) patients out of 688, 200 neoplastic lesions (all adenomas) were missed during the first examination. The miss rate was 16% for adenomas ≤ 5 mm and 2% for adenomas > 10 mm. The miss rates of patients with 0, 1, 2, or > 2 neoplastic polyps on the first examination was 5.3%, 19.6%, 23.5% and 35.5%, respectively. One year cumulative incidence rates of patients with 1, 2, or > 2 neoplastic polyps on the first examination were 18.4%, 21.1% and 34.2%, respectively.Conclusion:  Detection of multiple neoplasms on index colonoscopy predicts a high miss rate and cumulative incidence rate on surveillance colonoscopy. A substantial proportion of neoplasms detected at nearly 1-year postpolypectomy surveillance colonoscopy were missed at the initial total colonoscopy.
    Digestive Endoscopy 12/2004; 17(1):44 - 49. · 1.19 Impact Factor
  • Article: Protective actions of rat gastric epithelial E-cadherin expression against epithelial barrier dysfunctions induced by chemical hypoxia-reoxygenation in vitro.
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    ABSTRACT: E-cadherin expressed on gastric epithelium is reported to form adherence junctions and stabilize barrier functions. While hypoxia-reoxygenation is well known to cause gastric mucosal injury during reoxygenation, gastric E-cadherin actions against this stress remain unclear. In this study, using the oxygen depleting agent thioglycolic acid we examined whether E-cadherin expressed on rat cultured gastric epithelial cells has protective actions against epithelial barrier dysfunction induced by chemical hypoxia-reoxygenation. Chemical hypoxia was induced by incubating cells with 5 mm thioglycolic acid in glucose free medium for 60 min. Cells were then reoxygenated for 240 min by changing to normal medium. The expression of E-cadherin on the cell surface was measured with an enzyme immunoassay, and epithelial permeability was determined by the diffusion rate of FITC-dextran through the cell layer. E-cadherin expression increased during the 60 min hypoxic period, accompanied by activation of protein kinase C, protein kinase G and protein kinase A. The increased expression significantly diminished, but was considerably higher than the control values during reoxygenation for 180 min, which was partially due to generation of reactive oxygen species but not to activation of protein kinase. Conversely, epithelial permeability was stabilized during hypoxia, but increased only for 30 min of reoxygenation, probably due to generation of reactive oxygen species. Epithelial permeability during hypoxia was elevated by a combination of all the protein kinase inhibitors. An increase in the expression of E-cadherin during hypoxia through the activation of the kinases is likely to stabilize epithelial barrier functions. The reactive oxygen species generated during 30 min reoxygenation increased the molecular expression of E-cadherin less than during hypoxic stress. The transient break in the barrier functions caused by reactive oxygen species during reoxygenation appears to overcome the reactive oxygen species mediated cytoprotective action increasing E-cadherin expression.
    European Journal of Gastroenterology & Hepatology 01/2003; 14(12):1295-302. · 1.76 Impact Factor
  • Article: Immune responses in mice to intranasal and intracutaneous administration of a DNA vaccine encoding Helicobacter pylori-catalase.
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    ABSTRACT: 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.
    Vaccine 06/2002; 20(17-18):2336-42. · 3.77 Impact Factor