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Dive into the research topics where Keiichi Tominaga is active.

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Featured researches published by Keiichi Tominaga.


Gut | 2005

Methylation of the oestrogen receptor gene in non-neoplastic epithelium as a marker of colorectal neoplasia risk in longstanding and extensive ulcerative colitis

Shigehiko Fujii; Keiichi Tominaga; Kazuaki Kitajima; Jun Takeda; Toshihiro Kusaka; Mikio Fujita; Kazuhito Ichikawa; Shigeki Tomita; Yasuo Ohkura; Yuko Ono; Johji Imura; Tsutomu Chiba; Takahiro Fujimori

Background: Surveillance colonoscopy is widely recommended in patients with longstanding and extensive ulcerative colitis (UC) in order to detect colorectal neoplasia at an early stage. However, it still remains questionable whether surveillance colonoscopy effectively enables early detection of UC associated neoplasia. There is a great need for sensitive markers to identify individuals at increased risk of neoplasia. The oestrogen receptor (OR) gene shows age related methylation in the colorectal epithelium and is methylated frequently in sporadic colorectal neoplasia, suggesting that OR methylation may predispose to colorectal neoplasia. Aim: To clarify whether analysis of methylation of the OR gene in non-neoplastic epithelium can contribute to prediction of increased neoplasia risk in UC patients. Materials and methods: A total of 165 non-neoplastic colorectal epithelia from 30 patients with longstanding and extensive UC, including 13 UC patients with neoplasia and 17 patients without, were evaluated. Methylation specific polymerase chain reaction was performed to determine the methylation status of the OR gene. Results: Methylation of the OR gene was detected in 54 of 70 (77.1%) non-neoplastic colorectal epithelia in UC with neoplasia but in only 23 of 95 (24.2%) without neoplasia. Methylation of the OR gene was significantly more frequent in non-neoplastic epithelium from UC with neoplasia than in chronic colitic epithelium from UC without neoplasia. Furthermore, in UC with neoplasia, the OR gene was extensively methylated in non-neoplastic epithelia throughout the colorectum compared with those in UC without neoplasia. Conclusion: These results suggest that analysis of OR gene methylation may have potential as a useful marker for identifying individuals at increased risk of neoplasia among those with longstanding and extensive UC.


Clinical Cancer Research | 2005

Prediction of Colorectal Neoplasia by Quantitative Methylation Analysis of Estrogen Receptor Gene in Nonneoplastic Epithelium from Patients with Ulcerative Colitis

Keiichi Tominaga; Shigehiko Fujii; Kenichiroh Mukawa; Mikio Fujita; Kazuhito Ichikawa; Shigeki Tomita; Kazunari Kanke; Yuko Ono; Akira Terano; Hideyuki Hiraishi; Takahiro Fujimori

Purpose: The incidence of colorectal neoplasia has increased among patients with longstanding and extensive ulcerative colitis (UC). Therefore, surveillance colonoscopy has been widely recommended. However, there is controversy about the impact of cancer surveillance, and ways to improve its effectiveness are being sought. The estrogen receptor (ER) gene shows age-related methylation in the colorectal epithelium and is frequently methylated in colorectal neoplasia, suggesting that ER methylation occurs early in the process of colorectal tumorigenesis. Experimental Design: To clarify whether methylation analysis of the ER gene in nonneoplastic epithelium can help predict an increased risk for UC-associated neoplasia, a total of 105 nonneoplastic colorectal epithelia from 18 patients with longstanding and extensive UC, including 8 patients with neoplasia and 10 patients without neoplasia, were analyzed. In all patients, multiple samples were taken from six regions of the colorectum. The combined bisulfite restriction analysis method was used to determine the methylation status of the ER gene. Results: The mean methylation level of the ER gene was 25.4% in the nonneoplastic epithelia from UC patients with neoplasia, whereas it was only 4.0% in those without neoplasia (P < 0.001). The methylation level of the ER gene in UC patients with neoplasia was significantly higher than in UC patients without neoplasia throughout the colorectum except for the cecum. In UC patients with neoplasia, the mean ER methylation level in the distal colon (36.1%) was significantly higher than in the proximal colon (14.6%; P < 0.001). Conclusions: These results suggest that the analysis of ER gene methylation in nonneoplastic colorectal epithelium could have the potential to be a useful adjunct for identifying individuals with longstanding and extensive UC who are at increased risk of neoplasia and contribute to more effective cancer surveillance.


Journal of Gastroenterology | 2007

Comparison between endoscopic papillary balloon dilatation and endoscopic sphincterotomy for the treatment of common bile duct stones

Hidetaka Watanabe; Masashi Yoneda; Keiichi Tominaga; Tsuneo Monma; Kazunari Kanke; Tadahito Shimada; Akira Terano; Hideyuki Hiraishi

BackgroundThis study was designed to evaluate the therapeutic outcome and early postoperative complications, especially pancreatitis, of endoscopic papillary balloon dilation (EPBD) and endoscopic sphincterotomy (EST) in patients with common bile duct stones in our department.MethodsOne hundred eighty patients with common bile duct stones were randomized to undergo EPBD or EST. An 8-mm dilatation balloon was used for EPBD. Modified Cotton’s criteria, in which relatively mild pancreatitis is also included as a complication, were used to determine the incidence of postoperative complications.ResultsThe rate of complete removal of stones was significantly higher in the EST group (95.6%) than in the EPBD group (86.6%); for stones less than 10 mm in diameter, however, the rate with EPBD (93.8%) was almost equivalent to that with EST (98.1%). According to modified Cotton’s criteria, the incidence of postoperative pancreatitis was significantly higher in the EPBD group (16.7%) than in the EST group (6.7%). Bleeding was encountered in one patient (1.1%) in the EST group, but in none in the EPBD group. No fatal complication occurred in either the EPBD or the EST group.ConclusionsAlthough EPBD appears to be comparable to EST for removal of small common bile duct stones, mild postoperative pancreatitis is more likely to occur with EPBD than with EST.


Journal of Gastroenterology and Hepatology | 2005

Analysis of K-ras mutations and expression of cyclooxygenase-2 and gastrin protein in laterally spreading tumors.

Kenichiroh Mukawa; Shigehiko Fujii; Jun Takeda; Kazuaki Kitajima; Keiichi Tominaga; Yoko Chibana; Mikio Fujita; Kazuhito Ichikawa; Shigeki Tomita; Yuko Ono; Johji Imura; Hitoshi Kawamata; Tsutomu Chiba; Hideyuki Hiraishi; Akira Terano; Takahiro Fujimori

Background and Aim: Recent advances in colonoscopic techniques have led to the increased detection of, and interest in, superficial type colorectal tumors, and a new category, the ‘laterally spreading tumor (LST)’, has been proposed. However, the characteristics of the genetic alterations in these LSTs have not yet been fully determined. We therefore classified LSTs as LST‐granular (LST‐G) or LST‐non‐granular (LST‐NG), according to their macroscopic appearance, and examined the genetic alterations in these two tumor groups compared with those in protruded type tumors.


Digestive Diseases and Sciences | 2011

Evaluation of Microvessels in Colorectal Tumors by Narrow Band Imaging Magnification: Including Comparison with Magnifying Chromoendoscopy

Yutaka Okamoto; Hidetaka Watanabe; Keiichi Tominaga; Ryo Oki; Michiko Yamagata; Fumie Yokotsuka; Motoo Ishida; Hironori Masuyama; Hideyuki Hiraishi

AbstractsBackground/AimsNarrow band imaging (NBI) magnification analysis has entered use in clinical settings to diagnose colorectal tumors. Pit pattern analysis with magnifying endoscopy is already widely used to assess colorectal lesions and invasion depth. Our study compared diagnoses by vascular pattern analysis and pit pattern analysis with NBI magnification.MethodsWe examined 296 colorectal lesions—15 hyperplastic polyps (HP), 213 low-grade adenomas (L-Ad), 26 high-grade adenomas (H-Ad), 31 with intramucosal to scanty submucosal invasion (M-Sm-s), and 11 with massive submucosal invasion (Sm-m)—applying the system of Kudo et al. to analyze pit patterns, and the system of Tanaka et al. to analyze and classify vascular patterns by NBI into three categories: type A (hyperplasia pattern), type B (adenomatous pattern), and type C (carcinomatous pattern). Type C cases were subdivided into subtypes C1, C2, and C3. We used this system to examine histology type and invasion depth.ResultsDiagnostic sensitivity, specificity, and accuracy were 100% for both type II pit pattern HP and type A HP. Diagnostic sensitivity, specificity, and accuracy were 85.4, 94.5, and 93.2% for Vi and Vn pit pattern cancer and 95.2, 91.7, and 92.2% for type C cancer (no significant differences in sensitivity, specificity, or accuracy). Diagnostic sensitivity, specificity, and accuracy were comparable for Vi high-grade irregularity and Vn pit pattern Sm-m (90.9, 96.8, and 96.7%) and type C2/C3 Sm-m (90.1, 98.2, and 98.0%), with no significant differences in sensitivity, specificity, or accuracy.ConclusionsVascular pattern analysis by NBI magnification proved comparable to pit pattern analysis.


BMC Gastroenterology | 2013

Efficacy, safety and cost analyses in ulcerative colitis patients undergoing granulocyte and monocyte adsorption or receiving prednisolone

Keiichi Tominaga; Masakazu Nakano; Mina Hoshino; Kazunari Kanke; Hideyuki Hiraishi

BackgroundPatients with ulcerative colitis (UC) are treated with prednisolone (PSL), which causes adverse side effects. Extracorporeal granulocyte/monocyte adsorption (GMA) with an Adacolumn depletes elevated/activated myeloid lineage leucocytes as sources of inflammatory cytokines. We were interested to evaluate the efficacy, safety and the treatment cost for PSL and GMA.MethodsForty-one patients with active UC had achieved remission with GMA, at 1 or 2 sessions/week, up to 10 sessions (n=24) or with orally administered PSL (1mg/kg bodyweight, n=17). Clinical activity index (CAI) ≤4 was considered clinical remission. Following remission, patients received 5-aminosalicylic acid (2250-3000mg/day) or sulphasalazine (4000-6000mg/day) as maintenance therapy and were followed for 600 days. The total treatment cost was assessed based on 1€=150JPY.ResultsPSL was tapered after two weeks, and discontinued when a patient achieved remission. The average time to the disappearance of at least one major UC symptom (haematochezia, diarrhoea, or abdominal discomfort) was 15.3 days in the GMA group and 12.7 days in the PSL group, while time to remission was 27.9 days in the GMA group and 27.6 days in the PSL group, CAI 0.8 and 2.0, respectively. The Kaplan-Meier plots showed similar remission maintenance rates over the 600 days follow-up period. The average medical cost was 12739.4€/patient in the GMA group and 8751.3€ in the PSL group (P<0.05). In the GMA group, 5 transient adverse events were observed vs 10 steroid related adverse events in the PSL group (P<0.001).ConclusionsIn appropriately selected patients, GMA has significant efficacy with no safety concern. The higher cost of GMA vs PSL should be compromised by good safety profile of this non-pharmacological treatment intervention.


Digestive Endoscopy | 2010

IPMN penetration of the stomach.

Masakazu Nakano; Keiichi Tominaga; Hidetaka Watanabe; Kazunari Kanke; Masaya Tamano; Hideyuki Hiraishi

An 83‐year old Japanese man was transferred to our hospital due to a 1‐week history of melena and signs of disordered awareness. Esophagogastroduodenoscopy showed a villous tumor associated with massive white mucous discharge in the posterior wall of the gastric corpus, where pathologically identified mucin‐producing epithelium with nuclear atypia had developed into a papillary form. An abdominal enhanced computed tomography scan demonstrated communication between the dilated main pancreatic duct and the gastric lumen. Based on these findings, we reached a diagnosis of gastric penetration by an intraductal papillary mucinous neoplasm (IPMN) of the main pancreatic duct. IPMN is partly characterized by expansive mucinous growth that may result in penetration into adjacent organs.


BMC Gastroenterology | 2014

A second-look endoscopy may not reduce the bleeding after endoscopic submucosal dissection for gastric epithelial neoplasm

Fumiaki Takahashi; Naoto Yoshitake; Takashi Akima; Hitoshi Kino; Masakazu Nakano; Chieko Tsuchida; Kohei Tsuchida; Keiichi Tominaga; Takako Sasai; Hironori Masuyama; Hideyuki Hiraishi

BackgroundGastric endoscopic submucosal dissection (ESD) has gradually come to be recommended as the optimal treatment for early gastric cancer; however, one of the primary issues is postoperative bleeding. Although second-look endoscopy is conventionally performed to reduce the risk of postoperative bleeding, its benefit has not yet been clearly elucidated. The objective of this study was to elucidate the benefit of second-look endoscopy.MethodsA total of 459 lesions in patients were underwent gastric ESD from May 2004 to April 2013 at our hospital were included in the analysis. The patients were divided into those who had bleeding within 24 hours after ESD (immediate bleeding) and those in whom bleeding occurred 24 hours or more after the procedure (delayed bleeding); the underlying disease, age, lesion site, diameter of the resected specimen, and lesion diameter were analyzed to identify the risk factors for postoperative bleeding after ESD.ResultsPost-ESD immediate or delayed bleeding occurred in 23 of the 459 cases (5.0%). Second-look endoscopy was performed in 210 of 447 cases (47.0%) excluding 12 cases with immediate bleeding; in the remaining 237 of the 447 cases (53.0%), it was not performed. Post-ESD delayed bleeding occurred in 6 of the 210 cases (2.9%) and 5 of the 237 cases (2.1%), with no statistically significant difference between the two groups. Overall, the following factors were identified as the risk factors for postoperative bleeding: young age (P = 0.005), lesions in the L segment (P = 0.042), and large size of the resected specimen (P = 0.005). The risk factors identified in the immediate bleeding group were lesions in the L segment (P = 0.032), large size of the resected specimen (P < 0.001), and large tumor size (P = 0.011), and those in the delayed bleeding group were young age (P = 0.013) and concomitant renal disease (P = 0.011).ConclusionsThe results of this study suggest that second-look endoscopy after gastric ESD may not be useful for preventing postoperative bleeding.


Blood Purification | 2007

Selection of Anticoagulants for Leukocytapheresis Therapy in Cases of Active Ulcerative Colitis

Kazunari Kanke; Mina Hoshino; Keiichi Tominaga; Michiko Nakano; Akira Terano; Hideyuki Hiraishi

Background and Aim: Leukocytapheresis (LCAP) is an extracorporeal leukocyte removal therapy that removes immunocompetent leukocytes from the peripheral blood. Nafamostat mesilate (NM) is the most commonly used anticoagulant for LCAP due to various benefits associated with its use, such as a reduced likelihood of bleeding and minimization of adverse reactions caused by contact between blood and the LCAP device. However, adverse reactions have also been reported with NM administration. We reviewed the safety of anticoagulants other than NM, from the perspective of bradykinin production and the consequent drop in blood pressure during treatment. Methods: For each of 10 patients with ulcerative colitis, we used four types of anticoagulants sequentially [NM (30–50 mg), heparin, low-molecular-weight heparin (LMWH) and NM (1 mg), and LMWH] for LCAP. We then examined the changes in the blood bradykinin concentrations from the perspective of adverse reactions during LCAP. Results: The bradykinin production levels from Cellsorba EX varied, depending on the type of anticoagulant used. NM alone (30–50 mg) or LMWH + NM (1 mg) inhibited bradykinin production, whereas heparin alone or LMWH alone significantly accelerated it. However, an excessive fall of blood pressure was not noted in any of the cases. Use of LMWH alone was frequently associated with pressure elevations in the column. Conclusions: Given the significant benefits of minimized adverse reactions of LCAP and of continuation of LCAP, we suggest that an appropriate selection of the anticoagulant(s) may allow safer execution of LCAP.


Clinical Gastroenterology and Hepatology | 2017

Clinical and Pharmacokinetic Factors Associated With Adalimumab-Induced Mucosal Healing in Patients With Crohn’s Disease

Kenji Watanabe; Takayuki Matsumoto; Tadakazu Hisamatsu; Hiroshi Nakase; Satoshi Motoya; Naoki Yoshimura; Tetsuya Ishida; Shingo Kato; Tomoo Nakagawa; Motohiro Esaki; Masakazu Nagahori; Toshiyuki Matsui; Yuji Naito; Takanori Kanai; Yasuo Suzuki; Masanori Nojima; Mamoru Watanabe; Toshifumi Hibi; Akira Andoh; Toshifumi Ashida; Katsuya Endo; Yutaka Endo; Hiroshi Fujita; Mikihiro Fujiya; Ken Haruma; Sakiko Hiraoka; Yutaka Honda; Hideki Iijima; Bunei Iizuka; Kentaro Ikeya

Background & Aims We previously reported results from a prospective randomized controlled trial comparing the efficacy of adalimumab monotherapy versus combination with azathioprine for patients with Crohn’s disease (CD) who were naive to biologics and thiopurines. We performed a subanalysis of data from this study to evaluate factors associated with endoscopic response and mucosal healing in study participants. Methods We compared simple endoscopic scores for CD between patients with moderate to severe active CD randomly assigned groups that received adalimumab monotherapy (n = 85) or adalimumab in combination with azathioprine (n = 91), from June 2011 to June 2014 in Japan. We evaluated associations of simple endoscopic scores for CD with clinical factors and trough levels of adalimumab. Ultimately, 135 patients at Week 26 and 139 patients at Week 52 from 44 referral sites were analyzed for the present investigation. Results The odds for endoscopic response were significantly higher in the combination group than in the monotherapy group at Week 26 (odds ratio [OR], 2.12; 95% confidence interval [CI], 1.04–4.32) but not at Week 52 (OR, 1.50; 95% CI, 0.77–2.94). The odds of mucosal healing did not differ significantly between groups at Weeks 26 or 52. Simple endoscopic scores for CD at Week 0 was significantly associated with mucosal healing at Week 26 (OR, 0.80; 95% CI, 0.72–0.90) and at Week 52 (OR, 0.91; 95% CI, 0.84–0.99). Higher adalimumab trough level at Week 26 associated with mucosal healing at Week 52 (OR, 1.34; 95% CI, 1.14–1.58; P for trend = .001) and was significantly higher in patients with endoscopic response than in patients without endoscopic response at Weeks 26 and 52 (P < .001). Conclusions In a post hoc analysis of data from a randomized controlled trial of patients with moderate to severe CD, we found that adalimumab in combination with azathioprine increased trough levels of adalimumab. Higher trough levels of adalimumab associated with endoscopic response and mucosal healing at Weeks 26 and 52. UMIN registration No: 000005146.

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Masakazu Nakano

Dokkyo Medical University

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Naoto Yoshitake

Dokkyo Medical University

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Takeshi Sugaya

Dokkyo Medical University

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Takako Sasai

Dokkyo Medical University

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Akira Kanamori

Dokkyo Medical University

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