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Dive into the research topics where Keiichi Haga is active.

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Featured researches published by Keiichi Haga.


Journal of Gastroenterology and Hepatology | 2016

MAIT cells are activated and accumulated in the inflamed mucosa of ulcerative colitis

Keiichi Haga; Asako Chiba; Tomoyoshi Shibuya; Taro Osada; Dai Ishikawa; Tomohiro Kodani; Osamu Nomura; Sumio Watanabe; Sachiko Miyake

Ulcerative colitis (UC) is a chronic, relapsing and remitting, inflammatory disorder of the large intestine. Mucosal associated invariant T (MAIT) cells are a member of innate‐like lymphocytes found abundantly in the mucosal tissue. The contribution of MAIT cells in the pathogenesis of UC is still unclear; therefore, this study aimed at investigating the role of these cells in patients with UC.


The Journal of Rheumatology | 2016

Involvement of Mucosal-associated Invariant T cells in Ankylosing Spondylitis

Eri Hayashi; Asako Chiba; Kurisu Tada; Keiichi Haga; Mie Kitagaichi; Shihoko Nakajima; Makio Kusaoi; Fumio Sekiya; Michihiro Ogasawara; Ken Yamaji; Naoto Tamura; Yoshinari Takasaki; Sachiko Miyake

Objective. Ankylosing spondylitis (AS) is characterized by chronic inflammation of the axial and peripheral joints and ligamentous attachments. Gut immunity is thought to be involved in AS, because a prominent coexistence of gut and joint inflammation has been observed in patients with AS. Mucosal-associated invariant T (MAIT) cells are preferentially located in the gut lamina propria and produce inflammatory cytokines such as interleukin 17 (IL-17) and tumor necrosis factor-α (TNF-α), which are therapeutic targets for AS. This study aimed to investigate the involvement of MAIT cells in AS. Methods. The frequency of MAIT cells and their cytokine production were determined in patients with AS and healthy controls (HC). The expression of a MAIT cell activation marker (CD69) was analyzed in patients with AS by using flow cytometry. Results. The frequency of MAIT cells in the peripheral blood was lower in patients with AS compared with HC. The levels of IL-17 produced by MAIT cells after activation were higher in patients with AS than in the HC. CD69 expression on MAIT cells correlated with the Ankylosing Spondylitis Disease Activity Score in patients with AS. Conclusion. These results suggest the involvement of MAIT cells in the pathogenesis of AS.


Medical Science Monitor | 2012

Multiple carcinoid tumors of the small intestine preoperatively diagnosed by double-balloon endoscopy

Se-yong Lee; Shibuya Tomoyoshi; Keiichi Haga; Hitosi Sasaki; Chie Ogata; Osamu Nomura; Yuka Fukuo; Wataru Abe; Taro Osada; Akihito Nagahara; Tatsuo Ogihara; Hirohiko Kamiyama; Kazuhiro Sakamoto; Sumio Watanabe

Summary Background Multiple carcinoid tumors of the small intestine are rare and are very difficult to detect preoperatively. Case Report A 75-year-old woman in whom the bleeding focus could not be found by upper and lower endoscopy and abdominal CT was admitted for evaluation of anemia. We examined the patient with total double-balloon endoscopy (DBE) and located multiple submucosal tumors. The multiple carcinoid tumors were resected successfully under laparoscopy. Conclusions We report a case of a successful laparoscopic operation for multiple carcinoid tumors in the small intestine without intraoperative endoscopy. Total digestive tract observation using DBE is very useful for laparoscopic operation for multiple tumors in the small intestine.


American Journal of Cardiology | 2012

Usefulness of Prominently Projected Aortic Arch on Chest Radiograph to Predict Severe Tortuosity of the Right Subclavian or Brachiocephalic Artery in Patients Aged >44 Years Undergoing Coronary Angiography With a Right Radial Artery Approach

Yuji Nishizaki; Shinichiro Yamagami; Keiichi Haga; Masahiro Sesoko; Haruyo Yamashita; Katsumi Miyauchi; Hiroyuki Daida

Although it is well known that certain characteristics, such as older age, female gender, hypertension, and high body mass index, are closely associated with severe arterial tortuosity among patients undergoing transradial coronary angiography, few data are available regarding useful predictors of severe arterial tortuosity among geriatric patients. The purpose of the present study was to evaluate the characteristics of geriatric patients with severe tortuosity of the right subclavian artery or brachiocephalic artery. The coronary angiographic reports of patients with severe tortuosity of the right subclavian artery or brachiocephalic artery and age- and gender-matched control patients were retrospectively evaluated. A total of 847 consecutive patients underwent right transradial coronary angiography. Of these patients, 48 (5.7%) had severe tortuosity (29 women, age 73.4 ± 8.6 years). The factors associated with severe arterial tortuosity were greater body mass index (odds ratio 1.17, p = 0.02), the presence of a prominently projected aortic arch on a chest radiograph (odds ratio 5.62, p <0.01), and lower serum creatinine value (odds ratio 0.05, p <0.01). In conclusion, the presence of a prominently projected aortic arch on the chest radiograph is a useful predictor of severe arterial tortuosity.


Journal of Medical Case Reports | 2016

Obscure gastrointestinal bleeding caused by small intestinal lipoma: a case report

Noboru Yatagai; Hiroya Ueyama; Tomoyoshi Shibuya; Keiichi Haga; Masahito Takahashi; Osamu Nomura; Naoto Sakamoto; Taro Osada; Takashi Yao; Sumio Watanabe

BackgroundSmall intestinal lipomas are rare, usually asymptomatic, and most commonly encountered incidentally during investigation of the gastrointestinal tract for another reason. However, they may cause obscure gastrointestinal bleeding.Case presentationWe report a case of obscure gastrointestinal bleeding due to a small intestinal lipoma. A 69-year-old Japanese man on antiplatelet therapy presented to our department with tarry stools and anemic symptoms. A small intestinal tumor was detected by capsule endoscopy and double-balloon endoscopy. After laparoscopic resection, the tumor was confirmed to be a lipoma.ConclusionsSmall intestinal lipomas are difficult to detect by conventional modalities, but capsule endoscopy and double-balloon endoscopy are good modalities for the diagnosis of small intestinal lipomas. Treatment of small intestinal lipomas should be selected carefully, considering the tumor size, size of stalk, administration of antithrombotic therapy, and endoscopic operability.


Journal of Clinical Apheresis | 2018

Efficacy of cytapheresis for remission induction and dermatological manifestations of ulcerative colitis

Osamu Nomura; Taro Osada; Tomoyoshi Shibuya; Dai Ishikawa; Keiichi Haga; Tomohiro Kodani; Naoto Sakamoto; Tatsuo Ogihara; Ken Yamaji; Sumio Watanabe

In ulcerative colitis (UC) patients, cytapheresis depletes elevated and activated leucocytes, which are known to release inflammatory cytokines including tumor necrosis factor (TNF)‐α. Further, there are UC patients who develop erythema nodosum (EN) or pyoderma gangrenosum (PG) as extra‐intestinal manifestations of UC.


Intestinal Research | 2018

Successful remission of ulcerative colitis flare-up during pregnancy with adsorptive granulomonocytapheresis plus tacrolimus

Tomoyoshi Shibuya; Keiichi Haga; Masato Kamei; Koki Okahara; Shoko Ito; Masahito Takahashi; Osamu Nomura; Takashi Murakami; Masae Makino; Tomohiro Kodani; Dai Ishikawa; Naoto Sakamoto; Taro Osada; Tatsuo Ogihara; Sumio Watanabe; Akihito Nagahara

Ulcerative colitis (UC) is 1 of the 2 major phenotypes of chronic inflammatory bowel disease (IBD), which afflicts millions of individuals throughout the world with debilitating symptoms that impair function and quality of life. Further, IBD often affects women during childbearing age. Indeed, UC activity frequently increases during pregnancy, and the medications used to induce remission may adversely affect the health of the mother and the unborn child. We report successful induction of a remission in a UC case who experienced a flare-up in the first trimester of pregnancy. Upon relapse, she was treated with steroids and adsorptive granulomonocytapheresis (GMA) with the Adacolumn plus tacrolimus. This combination therapy induced a stable remission that was maintained during her entire pregnancy. She gave birth to a healthy child at 36 weeks of pregnancy with no maternal or fetal complications. Our experience indicates that GMA, as a non-drug therapeutic intervention with a favorable safety profile, plus tacrolimus might be a relevant treatment option for patients with active IBD during pregnancy. A future study of a large cohort of pregnant patients should strengthen our findings.


Inflammatory Bowel Diseases | 2018

The Microbial Composition of Bacteroidetes Species in Ulcerative Colitis Is Effectively Improved by Combination Therapy With Fecal Microbiota Transplantation and Antibiotics

Dai Ishikawa; Takashi Sasaki; Masahito Takahashi; Kyoko Kuwahara-Arai; Keiichi Haga; Shoko Ito; Koki Okahara; Akihito Nakajima; Tomoyoshi Shibuya; Taro Osada; Keiichi Hiramatsu; Sumio Watanabe; Akihito Nagahara

Background We previously reported that fresh fecal microbiota transplantation (FMT) after triple-antibiotic therapy (amoxicillin, fosfomycin, and metronidazole [AFM]; A-FMT) synergistically contributed to the recovery of phylum Bacteroidetes composition associated with the endoscopic severity and treatment efficacy of ulcerative colitis (UC). Here, we performed further microbial analyses using a higher-resolution method to identify the key bacterial species in UC and determine whether viable Bacteroidetes species from donor feces were successfully colonized by A-FMT. Methods The taxonomic composition of Bacteroidetes in 25 healthy donors and 27 UC patients at baseline was compared at the species level using a heat-shock protein (hsp) 60-based microbiome method. Microbiota alterations before and after treatment of UC patients were also analyzed in 24 cases (n = 17 A-FMT; n = 3 mono-AFM; n = 4 mono-FMT). Results We found species-level dysbiosis within the phylum Bacteroidetes in UC samples, which was associated with reduced species diversity, resulting from hyperproliferation and hypoproliferation of particular species. Moreover, in responders treated with A-FMT, diversity was significantly recovered at 4 weeks after a fresh round of FMT, after which high degrees of similarity in Bacteroidetes species composition among recipients and donors were observed. Conclusions A-FMT alleviated intestinal dysbiosis, which is caused by the loss of Bacteroidetes species diversity in patients with UC. Eradication of dysbiotic indigenous Bacteroidetes species by AFM pretreatment might promote the colonization of viable Bacteroidetes cells, thereby improving the intestinal microbiota dysbiosis induced by UC. Our findings serve as a basis for further investigations into the mechanisms of FMT.


Digestion | 2018

Improved Visibility of Barrett’s Esophagus with Linked Color Imaging: Inter- and Intra-Rater Reliability and Quantitative Analysis

Tsutomu Takeda; Akihito Nagahara; Kei Ishizuka; Shoki Okubo; Keiichi Haga; Maiko Suzuki; Akihito Nakajima; Hiroyuki Komori; Yoichi Akazawa; Kentaro Izumi; Kohei Matsumoto; Hiroya Ueyama; Yuji Shimada; Kenshi Matsumoto; Daisuke Asaoka; Tomoyoshi Shibuya; Naoto Sakamoto; Taro Osada; Mariko Hojo; Shuko Nojiri; Sumio Watanabe

Background/Aims: To evaluate the usefulness of linked color imaging (LCI) and blue LASER imaging (BLI) in Barrett’s esophagus (BE) compared with white light imaging (WLI). Methods: Five expert and trainee endoscopists compared WLI, LCI, and BLI images obtained from 63 patients with short-segment BE. Physicians assessed visibility as follows: 5 (improved), 4 (somewhat improved), 3 (equivalent), 2 (somewhat decreased), and one (decreased). Scores were evaluated to assess visibility. The inter- and intra-rater reliability (intra-class correlation coefficient) of image assessments were also evaluated. Images were objectively evaluated based on L* a* b* color values and color differences (ΔE*) in a CIELAB color space system. Results: Improved visibility compared with WLI was achieved for LCI: 44.4%, BLI: 0% for all endoscopists; LCI: 55.6%, BLI: 1.6% for trainees; and LCI: 47.6%, BLI: 0% for experts. The visibility score of trainees compared with experts was significantly higher for LCI (p = 0.02). Intra- and inter-rater reliability ratings for LCI compared with WLI were “moderate” for trainees, and “moderate-substantial” for experts. The ΔE* revealed statistically significant differences between WLI and LCI. Conclusion: LCI improved the visibility of short-segment BE compared with WLI, especially for trainees, when evaluated both subjectively and objectively.


Inflammatory Bowel Diseases | 2017

Changes in Intestinal Microbiota Following Combination Therapy with Fecal Microbial Transplantation and Antibiotics for Ulcerative Colitis.

Dai Ishikawa; Takashi Sasaki; Taro Osada; Kyoko Kuwahara-Arai; Keiichi Haga; Tomoyoshi Shibuya; Keiichi Hiramatsu; Sumio Watanabe

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