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Dive into the research topics where Noriko Nishiyama is active.

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Featured researches published by Noriko Nishiyama.


World Journal of Gastroenterology | 2013

Efficacy and safety of over-the-scope clip: Including complications after endoscopic submucosal dissection

Noriko Nishiyama; Hirohito Mori; Hideki Kobara; Kazi Rafiq; Shintarou Fujihara; Mitsuyoshi Kobayashi; Makoto Oryu; Tsutomu Masaki

AIM To retrospectively review the results of over-the-scope clip (OTSC) use in our hospital and to examine the feasibility of using the OTSC to treat perforations after endoscopic submucosal dissection (ESD). METHODS We enrolled 23 patients who presented with gastrointestinal (GI) bleeding, fistulae and perforations and were treated with OTSCs (Ovesco Endoscopy GmbH, Tuebingen, Germany) between November 2011 and September 2012. Maximum lesion size was defined as lesion diameter. The number of OTSCs to be used per patient was not decided until the lesion was completely closed. We used a twin grasper (Ovesco Endoscopy GmbH, Tuebingen, Germany) as a grasping device for all the patients. A 9 mm OTSC was chosen for use in the esophagus and colon, and a 10 mm device was used for the stomach, duodenum and rectum. The overall success rate and complications were evaluated, with a particular emphasis on patients who had undergone ESD due to adenocarcinoma. In technical successful cases we included not only complete closing by using OTSCs, but also partial closing where complete closure with OTSCs is almost difficult. In overall clinical successful cases we included only complete closing by using only OTSCs perfectly. All the OTSCs were placed by 2 experienced endoscopists. The sites closed after ESD included not only the perforation site but also all defective ulcers sites. RESULTS A total of 23 patients [mean age 77 years (range 64-98 years)] underwent OTSC placement during the study period. The indications for OTSC placement were GI bleeding (n = 9), perforation (n = 10), fistula (n = 4) and the prevention of post-ESD duodenal artificial ulcer perforation (n = 1). One patient had a perforation caused by a glycerin enema, after which a fistula formed. Lesion closure using the OTSC alone was successful in 19 out of 23 patients, and overall success rate was 82.6%. A large lesion size (greater than 20 mm) and a delayed diagnosis (more than 1 wk) were the major contributing factors for the overall unsuccessful clinical cases. The location of the unsuccessful lesion was in the stomach. The median operation time in the successful cases was 18 min, and the average observation time was 67 d. During the observation period, none of the patients experienced any complications associated with OTSC placement. In addition, we successfully used the OTSC to close the perforation site after ESD in 6 patients. This was a single-center, retrospective study with a small sample size. CONCLUSION The OTSC is effective for treating GI bleeding, fistulae as well as perforations, and the OTSC technique proofed effective treatment for perforation after ESD.


Digestive Endoscopy | 2013

Successful closing of duodenal ulcer after endoscopic submucosal dissection with over-the-scope clip to prevent delayed perforation.

Hirohito Mori; Fujihara Shintaro; Hideki Kobara; Noriko Nishiyama; Kazi Rafiq; Mitsuyoshi Kobayashi; Toshiaki Nakatsu; Noboru Miichi; Yasuyuki Suzuki; Tsutomu Masaki

Closure of post‐endoscopic submucosal dissection (ESD) duodenal artificial ulcer is not common in the clinical setting. We consider that post‐ESD ulcer closure by an over‐the‐scope‐clip (OTSC) method is one of the most effective ways to prevent delayed perforation. We report here two cases of mucosal duodenal cancer in a 65‐year‐old woman and in a 78‐year‐old man. Pathological examinations of the resected specimens revealed well‐differentiated adenocarcinomas. In these two clinical cases, we successfully carried out complete closures of post‐ESD duodenal ulcer using OTSC without any complications.


International Journal of Oncology | 2013

Antitumor effect of metformin in esophageal cancer: In vitro study

Mitsuyoshi Kobayashi; Kiyohito Kato; Hisakazu Iwama; Shintaro Fujihara; Noriko Nishiyama; Shima Mimura; Yuka Toyota; Takako Nomura; Kei Nomura; Joji Tani; Hisaaki Miyoshi; Hideki Kobara; Hirohito Mori; Koji Murao; Tsutomu Masaki

Recent studies suggest that metformin, which is a member of the biguanide family and commonly used as an oral anti-hyperglycemic agent, may reduce cancer risk and improve prognosis of numerous types of cancer. However, the mechanisms underlying the antitumor effect of metformin on esophageal cancer remain unknown. The goal of the present study was to evaluate the effects of metformin on the proliferation of human ESCC in vitro, and to study changes in the expression profile of microRNAs (miRNAs), since miRNAs have previously been associated with the antitumor effects of metformin in other human cancers. The human ESCC cell lines T.T, KYSE30 and KYSE70 were used to study the effects of metformin on human ESCC in vitro. In addition, we used miRNA array tips to explore the differences between miRNAs in KYSE30 cells with and without metformin treatment. Metformin inhibited the proliferation of T.T, KYSE30 and KYSE70 cells in vitro. Metformin blocked the cell cycle in G0/G1 in vitro. This blockade was accompanied by a strong decrease of G1 cyclins, especially cyclin D1, as well as decreases in cyclin-dependent kinase (Cdk)4, Cdk6 and phosphorylated retinoblastoma protein (Rb). In addition, the expression of miRNAs was markedly altered with the treatment of metformin in vitro. Metformin inhibited the growth of three ESCC cell lines, and this inhibition may have involved reductions in cyclin D1, Cdk4 and Cdk6.


Gastrointestinal Endoscopy | 2013

Bloc biopsy by using submucosal endoscopy with a mucosal flap method for gastric subepithelial tumor tissue sampling (with video).

Hideki Kobara; Hirohito Mori; Shintaro Fujihara; Noriko Nishiyama; Mitsuyoshi Kobayashi; Hideki Kamata; Tsutomu Masaki

Subepithelial tumors (SETs) include widely malignant tumors such as GI stromal tumors, malignant lymphomas, carcinoid tumors, gastric cancers similar to SETs, and benign tumors such as leiomyomas, aberrant pancreas, and lipomas. Currently, minimally invasive local resection techniques such as hybrid natural orifice transluminal endoscopic surgery (NOTES), which consists of endoscopic full-thickness gastric resection, have been developed for the treatment of GI stromal tumors. 1 However, there is no consensus regarding the optimal strategy for the tissue diagnosis of SETs before determining the plans for further management such as surgical resection or observation. SET differentiation is essentially important, because different types of lesions may need different management, prognoses, and therapeutic options. EUS morphologic features alone have limited specificity for the diverse subtypes of SETs, and EUS cannot differentiate between a benign or malignant origin. Recently, several diagnostic methods have been proposed for the tissue diagnosis of SETs. EUS-guided FNA (EUS-FNA) biopsy has been introduced as an easy, safe, and valuable method for obtaining tissue samples for the accurate diagnosis of GI SETs. 2-7 In


International Journal of Oncology | 2015

Antidiabetic drug metformin inhibits esophageal adenocarcinoma cell proliferation in vitro and in vivo.

Shintaro Fujihara; Kiyohito Kato; Asahiro Morishita; Hisakazu Iwama; Tomoko Nishioka; Taiga Chiyo; Noriko Nishiyama; Hisaaki Miyoshi; Mitsuyoshi Kobayashi; Hideki Kobara; Hirohito Mori; Keiichi Okano; Yasuyuki Suzuki; Tsutomu Masaki

Esophageal carcinoma is the eighth most common cancer worldwide and the sixth leading cause of cancer-related deaths, with one of the worst prognoses of any form of cancer. Treatment with the anti-diabetic drug metformin has been associated with reduced cancer incidence in patients with type 2 diabetes. This study therefore evaluated the effects of metformin on the proliferation, in vitro and in vivo, of human esophageal adenocarcinoma cells, as well as the microRNAs associated with the antitumor effects of metformin. Metformin inhibited the proliferation of the esophageal adenocarcinoma cell lines OE19, OE33, SK-GT4 and OACM 5.1C, blocking the G0 to G1 transition in the cell cycle. This was accompanied by strong reductions in G1 cyclins, especially cyclin D1, cyclin-dependent kinase (Cdk)4, and Cdk6, and decreases in retinoblastoma protein phosphorylation. In addition, metformin reduced the phosphorylation of epidermal growth factor receptor and insulin-like growth factor and insulin-like growth factor-1 receptor, as well as angiogenesis-related proteins, such as vascular endothelial growth factor, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2. Metformin also markedly altered microRNA expression. Treatment with metformin of athymic nude mice bearing xenograft tumors reduced tumor proliferation. These findings suggest that metformin may have clinical use in the treatment of esophageal adenocarcinoma.


Endoscopy | 2012

Local steroid injection into the artificial ulcer created by endoscopic submucosal dissection for gastric cancer: prevention of gastric deformity

Hirohito Mori; Kazi Rafiq; Hideki Kobara; Shintarou Fujihara; Noriko Nishiyama; Mitsuyoshi Kobayashi; Takashi Himoto; Reiji Haba; Masanobu Hagiike; Kunihiko Izuishi; Keiichi Okano; Yasuyuki Suzuki; Tsutomu Masaki

BACKGROUND AND STUDY AIMS Endoscopic submucosal dissection (ESD) of large gastric lesions results in an extensive artificial ulcer that can lead to marked gastric deformity. The aim of the current study was to evaluate therapeutic efficacy in the prevention of gastric deformity of local triamcinolone acetonide (TCA) injection into the extensive artificial ulcer following ESD. PATIENTS AND METHODS A total of 45 patients who were diagnosed with early gastric cancer were enrolled. Patients were randomly assigned by the sealed-envelope randomization method to either local TCA injections (n = 21) or sham-control (n = 20) groups. Two clips were placed at the two maximum outer edges of the artificial ulcer after the lesion had been resected (Day 0). Local TCA injections were performed on postoperative Day 5 and Day 12. The distance between the two clips was measured by endoscopic measuring forceps on Days 5, 12, 30, and 60. Granulation formation and gastric deformity were evaluated by visual analog scale (VAS) on Days 30 and 60. RESULTS Local TCA injection did not alter clip-to-clip distance on postoperative Day 60, and formation of flat granulation tissue over the ulcer was followed by regenerative mucosa without any gastric deformity. The sham-control group showed significant shortening of clip-to-clip distance compared with the local steroid-injected group and protruded forms of granulation tissue with mucosal convergence. Histological evaluation revealed prominent growth of neovessels, swelling, and marked increases in endothelial cells in the local steroid-injected group compared with the sham-control group. CONCLUSIONS Local steroid injection into the floor of a post-ESD artificial ulcer promotes the formation of granulation tissue at an early stage of the healing process leading to regeneration of gastric mucosa without mucosal convergence or gastric deformity.


Journal of Gastroenterology and Hepatology | 2013

Steroid permeation into the artificial ulcer by combined steroid gel application and balloon dilatation: Prevention of esophageal stricture

Hirohito Mori; Kazi Rafiq; Hideki Kobara; Shintaro Fujihara; Noriko Nishiyama; Makoto Oryuu; Yasuyuki Suzuki; Tsutomu Masaki

Local steroid injection therapy is effective for preventing esophageal stricture after endoscopic submucosal dissection (ESD) but is associated with the risk of puncture‐related complications, such as bleeding. We evaluated the effectiveness of the application of triamcinolone acetonide gel following permeation into a large artificial ESD ulcer by balloon dilatation compared with steroid injection.


Oncology Reports | 2013

The efficacy and safety of prophylactic closure for a large mucosal defect after colorectal endoscopic submucosal dissection

Shintaro Fujihara; Hirohito Mori; Hideki Kobara; Noriko Nishiyama; Mitsuyoshi Kobayashi; Kazi Rafiq; Tsutomu Masaki

Endoscopic submucosal dissection (ESD) is not a common treatment for colorectal neoplasms because of its technical difficulties and has a higher incidence of complication. In particular, perforation is one of the severe complications and these patients require surgical intervention. However, whether prophylactic closure after colorectal ESD prevents perforation and other complications is not known. In the present study, we assessed the efficacy and safety of prophylactic closure for a large mucosal defect after colorectal ESD using a conventional clip and over-the-scope clip (OTSC) system. From April 2010 to December 2012, 68 patients with colorectal tumors were treated with ESD. The prohylactic closure was indicated for patients with excessive coagulation in the muscularis propria or larger resection size. The closure group reduced the peritoneal inflammatory reaction and abdominal symptoms without increasing complications. The closure group also had a significantly lower WBC count (post operative day 1), CRP (post operative day 4) and abdominal pain after colorectal ESD compared to the non-closure group. Perforation occurred in 1 case, and postoperative bleeding in 2 cases, with only 1 bleeding case needing an emergency endoscopy in the non-closure group. One perforation case needed emergency surgery because the endoscopic treatment was ineffective. Without increasing adverse effects, the prophylactic closure efficiently reduced the inflammatory reaction and abdominal symptoms of colorectal ESD in patients with large superficial colorectal neoplasms.


Gastroenterology Research and Practice | 2012

Metabolic syndrome, obesity, and gastrointestinal cancer.

Shintaro Fujihara; Hirohito Mori; Hideki Kobara; Noriko Nishiyama; Mitsuyoshi Kobayashi; Makoto Oryu; Tsutomu Masaki

Metabolic syndrome is a cluster of metabolic abnormalities and is defined as the presence of three or more of the following factors: increased waist circumference, elevated triglycerides, low high-density lipoprotein cholesterol, high blood pressure, and high fasting glucose. Obesity, which is accompanied by metabolic dysregulation often manifested in the metabolic syndrome, is an established risk factor for many cancers. Adipose tissue, particularly visceral fat, is an important metabolic tissue as it secretes systemic factors that alter the immunologic, metabolic, and endocrine milieu and also promotes insulin resistance. Within the growth-promoting, proinflammatory environment of the obese state, cross-talk between macrophages, adipocytes, and epithelial cells occurs via obesity-associated hormones, adipocytokines, and other mediators that may enhance cancer risk and progression. This paper synthesizes the evidence on key molecular mechanisms underlying the obesity-cancer link.


BioMed Research International | 2014

Current Innovations in Endoscopic Therapy for the Management of Colorectal Cancer: From Endoscopic Submucosal Dissection to Endoscopic Full-Thickness Resection

Shintaro Fujihara; Hirohito Mori; Hideki Kobara; Noriko Nishiyama; Tae Matsunaga; Maki Ayaki; Tatsuo Yachida; Asahiro Morishita; Kunihiko Izuishi; Tsutomu Masaki

Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment for colorectal cancer. However, due to technical difficulties and an increased rate of complications, ESD is not widely used in the colorectum. In some cases, endoscopic treatment alone is insufficient for disease control, and laparoscopic surgery is required. The combination of laparoscopic surgery and endoscopic resection represents a new frontier in cancer treatment. Recent developments in advanced polypectomy and minimally invasive surgical techniques will enable surgeons and endoscopists to challenge current practice in colorectal cancer treatment. Endoscopic full-thickness resection (EFTR) of the colon offers the potential to decrease the postoperative morbidity and mortality associated with segmental colectomy while enhancing the diagnostic yield compared to current endoscopic techniques. However, closure is necessary after EFTR and natural transluminal endoscopic surgery (NOTES). Innovative methods and new devices for EFTR and suturing are being developed and may potentially change traditional paradigms to achieve minimally invasive surgery for colorectal cancer. The present paper aims to discuss the complementary role of ESD and the future development of EFTR. We focus on the possibility of achieving EFTR using the ESD method and closing devices.

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