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Dive into the research topics where Gen Sugiyama is active.

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Featured researches published by Gen Sugiyama.


Alimentary Pharmacology & Therapeutics | 2009

Clinical trial: comparison of alendronate and alfacalcidol in glucocorticoid‐associated osteoporosis in patients with ulcerative colitis

S. Kitazaki; Keiichi Mitsuyama; Junya Masuda; K. Harada; Hiroshi Yamasaki; Kotaro Kuwaki; Hiroko Takedatsu; Gen Sugiyama; Osamu Tsuruta; Michio Sata

Background  Bone loss is often observed in patients with ulcerative colitis, particularly if they require glucocorticoids.


Journal of Gastroenterology and Hepatology | 2012

Serum immunoglobulin G4 associated with number and distribution of extrapancreatic lesions in type 1 autoimmune pancreatitis patients

Ryohei Kaji; Hidetoshi Takedatsu; Yoshinobu Okabe; Yusuke Ishida; Gen Sugiyama; Koji Yonemoto; Keiichi Mitsuyama; Osamu Tsuruta; Michio Sata

Background and Aim:  Type 1 autoimmune pancreatitis (AIP) is characterized by the increase of serum immunoglobulin (Ig)G4 and abundant IgG4 plasma cell infiltration in the pancreas and various extrapancreatic lesions (EPL), which are proposed as IgG4‐related disease. We assessed the correlation between serum IgG4 and the number of EPL, and the association between serum IgG4 and the distribution of EPL in type 1 AIP patients.


Digestive Endoscopy | 2010

DIRECT CHOLANGIOSCOPY USING A DOUBLE‐BALLOON ENTEROSCOPE: CHOLEDOCHOJEJUNOSTOMY WITH INTRADUCTAL BILIARY CARCINOMA

Yoshinobu Okabe; Kotaro Kuwaki; Hiroshi Kawano; Ryohei Kaji; Gen Sugiyama; Yusuke Ishida; Makiko Yasumoto; Yoshiki Naito; Atsushi Toyonaga; Osamu Tsuruta; Michio Sata

A 75‐year‐old man who underwent choledochojejunostomy for gallstones 30 years ago was hospitalized for general malaise. Abdominal computed tomography revealed marked dilation of the intrahepatic bile duct in the right lobe and an image of a hypervascular tumor. Endoscopic retrograde cholangiography using double‐balloon enteroscopy (DBE) showed a filling defect that was localized to the right hepatic bile duct. Furthermore, the scope was able to readily pass through the anastomosed site of the choledochojejunostomy and, therefore, we observed the interior of the bile duct using the same scope. We obtained an image showing a whitish, papillary‐like tumor, and a biopsy of the tumor rendered the pathology of intraductal papillary mucinous carcinoma. Direct cholangioscopy using DBE is a useful diagnostic tool, particularly in patients with a past history of choledochojejunostomy.


World Journal of Gastroenterology | 2014

Evaluation of endoscopic biliary stenting for obstructive jaundice caused by hepatocellular carcinoma.

Gen Sugiyama; Yoshinobu Okabe; Yusuke Ishida; Fumihiko Saitou; Ryuichi Kawahara; Hiroto Ishikawa; Hiroyuki Horiuchi; Hisafumi Kinoshita; Osamu Tsuruta; Michio Sata

AIM To review the usefulness of endoscopic biliary stenting for obstructive jaundice caused by hepatocellular carcinoma and identify problems that may need to be addressed. METHODS The study population consisted of 36 patients with obstructive jaundice caused by hepatocellular carcinoma (HCC) who underwent endoscopic biliary stenting (EBS) as the initial drainage procedure at our hospital. The EBS technical success rate and drainage success rate were assessed. Drainage was considered effective when the serum total bilirubin level decreased by 50% or more following the procedure compared to the pre-drainage value. Survival time after the procedure and patient background characteristics were assessed comparatively between the successful drainage group (group A) and the non-successful drainage group (group B). The EBS stent patency duration in the successful drainage group (group A) was also assessed. RESULTS The technical success rate was 100% for both the initial endoscopic nasobiliary drainage and EBS in all patients. Single stenting was placed in 21 patients and multiple stenting in the remaining 15 patients. The drainage successful rate was 75% and the median interval to successful drainage was 40 d (2-295 d). The median survival time was 150 d in group A and 22 d in group B, with the difference between the two groups being statistically significant (P < 0.0001). There were no statistically significant differences between the two groups with respect to patient background characteristics, background liver condition, or tumor factors; on the other hand, the two groups showed statistically significant differences in patients without a history of hepatectomy (P = 0.009) and those that received multiple stenting (P = 0.036). The median duration of stent patency was 43 d in group A (2-757 d). No early complications related to the EBS technique were encountered. Late complications occurred in 13 patients (36.1%), including stent occlusion in 7, infection in 3, and distal migration in 3. CONCLUSION EBS is recommended as the initial drainage procedure for obstructive jaundice caused by HCC, as it appears to contribute to prolongation of survival time.


Molecular Medicine Reports | 2008

Roles of high-mobility group box 1 in murine experimental colitis

Hiroshi Yamasaki; Keiichi Mitsuyama; Junya Masuda; Kotaro Kuwaki; Hidetoshi Takedatsu; Gen Sugiyama; Shingo Yamada; Michio Sata

High-mobility group box 1 (HMGB1) plays a role in inflammatory and immune-mediated diseases. This study investigated the role of HMGB1 in colonic inflammation. Colitis was induced by orally feeding mice 4.5% dextran sulfate sodium (DSS) for up to 7 days. Mice were sacrificed on days 0, 3, 7 and 10, and the colon harvested for the measurement of HMGB1 and pro-inflammatory cytokines. To block HMGB1 induction, an anti-HMGB1 antibody was administered intraperitoneally 2 h before or 3 days after the induction of colitis, and disease severity was assessed by clinical and histological scoring. The colonic levels of tumor necrosis factor-α and interleukin-1β were elevated in relation to disease severity. The level of HMGB1 increased more slowly than that of the cytokines. Immunohistochemical study of the colons showed that the tissues of mice treated with DSS had a higher expression of HMGB1 and its receptor - the receptor for advanced glycation end products - than normal controls, especially in inflammatory infiltrates. The anti-HMGB1 antibody ameliorated tissue damage. In conclusion, HMGB1 is an important mediator of colonic inflammation, and suppression of this protein partially protects against colonic inflammation.


PLOS ONE | 2016

Evaluation of Resistance-Associated Substitutions in NS5A Using Direct Sequence and Cycleave Method and Treatment Outcome with Daclatasvir and Asunaprevir for Chronic Hepatitis C Genotype 1.

Tatsuya Ide; Yuichiro Eguchi; Masaru Harada; Kunihide Ishii; Masaru Morita; Yasuyo Morita; Gen Sugiyama; Hirofumi Fukushima; Yoichi Yano; Kazunori Noguchi; Hiroki Nakamura; Junjiro Hisatomi; Hiroto Kumemura; Miki Shirachi; Shinji Iwane; Michiaki Okada; Yuichi Honma; Teruko Arinaga-Hino; Ichiro Miyajima; Kei Ogata; Reiichiro Kuwahara; Keisuke Amano; Toshihiro Kawaguchi; Ryoko Kuromatsu; Takuji Torimura

Background The aim of this study was to evaluate the efficacy of daclatasvir plus asunaprevir therapy in patients infected with hepatitis C virus and determine its relevance to resistant variants. Methods A total of 629 consecutive patients infected with hepatitis C virus genotype 1 were assessed. Daclatasvir (60 mg/day) plus asunaprevir (200 mg/day) was given for 24 weeks. The virological responses and resistance-associated substitutions of hepatitis C virus mutants were examined by the direct sequence and cycleave methods were evaluated. Results Overall, 89.4% (555/621) of patients exhibited a sustained virological response (SVR). The SVR rates in the patients with wild type, mixed, and mutant type Y93 by direct sequencing were 92.5% (520/562), 70.3% (26/37), and 42.9% (9/21), respectively. The SVR rates in the patients with 100%, 90%, 80%-30%, and 20%-0% Y93 wild by the cycleave method were 93.4% (456/488), 88.2%(30/34), 56.0%(14/25), and 36.8%(7/19), respectively. In contrast, the SVR rates for the wild type and mixed/mutant type L31 by direct sequencing were 90.2% (534/592) and 72.4% (21/29), respectively. In the multivariate analyses, the wild type Y93, no history of simeprevir therapy, the wild type L31, and low HCV RNA level were independent factors of SVR. Conclusion NS5A resistance-associated substitutions, especially Y93H, were major factors predicting the SVR. Although direct sequencing can predict the SVR rate, the cycleave method is considered to be more useful for predicting the SVR when used in combination.


Digestive Endoscopy | 2013

Technique of reintervention for stent dysfunction in patients with malignant hilar biliary stricture

Yoshinobu Okabe; Yusuke Ishida; Tomoyuki Ushijima; Gen Sugiyama; Michio Sata

At present, the endoscopic approach is the most commonly adopted method for stenting in patients with unresectable malignant hilar biliary stricture. This procedure is important, as it determines the quality of life and prognosis of the patient. Regarding the quality of the stent material, self‐expandable metallic stents (SEMS) are expected to show longer‐term stent patency than plastic stents (PS), and their use as devices of first choice has been increasing. However, complications such as stent occlusion due to tumor ingrowth or biliary sludge formation occur at a considerably high frequency, necessitating reintervention in a considerable number of patients. In the case of dysfunction of an implanted PS, the stent is removed, and the lumen ofthe bile duct is cleaned, followed by placement of a new stent. In the event of dysfunction of a SEMS, cleaning of the lumen of the SEMS and placement of a second stent (PS is preferable) are carried out. Nevertheless, the results have not been entirely gratifying. Development of SEMS or PS suited to multidisciplinary treatment that would enable uncomplicated reintervention is anticipated.


Digestive Endoscopy | 2013

Evaluation of magnifying endoscopy using narrow band imaging using ex vivo bile duct (with video).

Yusuke Ishida; Yoshinobu Okabe; Ryohei Kaji; Makiko Yasumoto; Yu Sasaki; Tomoyuki Ushijima; Gen Sugiyama; Yuhei Kitasato; Hiroyuki Horiuchi; Hisafumi Kinoshita; Osamu Tsuruta; Michio Sata

Detailed endoscopic findings of the bile duct mucosa, even of the non‐neoplastic mucosa, have not yet been established. The aim of the present study was to compare a currently used video cholangioscope (CCS) with a magnifying endoscope (ME) that is commonly used for the gastrointestinal tract, for visualization of the bile duct mucosa.


Digestive Endoscopy | 2012

USE OF A PARTIALLY COVERED SELF‐EXPANDABLE METALLIC STENT TO TREAT A BILIARY STRICTURE SECONDARY TO CHRONIC PANCREATITIS COMPLICATED BY RECURRENT CHOLANGITIS: A CASE REPORT

Yoshinobu Okabe; Yusuke Ishida; Yu Sasaki; Tomoyuki Ushijima; Gen Sugiyama; Osamu Tsuruta

The patient was a 69 year old man who had been diagnosed with alcoholic chronic pancreatitis and lower common bile duct (CBD) stricture. He subsequently developed cholangitis 2–3 times a year, and we replaced the endoscopic biliary stent (EBS) each time. In April 2010, he was admitted because of complication by a liver abscess and acute cholangitis. We performed percutaneous transhepatic liver abscess drainage. The inflammatory findings then rapidly improved, but the patient developed acute cholangitis due to the sludge and the stones. Then, we placed a partially covered self‐expandable metallic stent (C‐SEMS) in the lower CBD and performed endoscopic lithotripsy through the C‐SEMS, and the cholangitis subsequently improved. Two weeks after, we removed the C‐SEMS endoscopically and replaced it with a 10 Fr plastic stent; since then there have been no recurrences of cholangitis. Our experience in this case suggested that when a plastic stent is placed long‐term to treat a biliary stricture associated with chronic pancreatitis, it might be useful to also control biliary sludge and stones using a C‐SEMS.


Journal of Hepato-biliary-pancreatic Sciences | 2012

Endoscopic ultrasonographic study of autoimmune pancreatitis and the effect of steroid therapy

Yoshinobu Okabe; Yusuke Ishida; Ryohei Kaji; Gen Sugiyama; Makiko Yasumoto; Yoshiki Naito; Atsushi Toyonaga; Osamu Tsuruta; Michio Sata

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