Masahide Kita
Okayama University
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Featured researches published by Masahide Kita.
Endoscopy | 2013
Yoshiro Kawahara; Keisuke Hori; Ryuta Takenaka; Junichiro Nasu; Seiji Kawano; Masahide Kita; Takao Tsuzuki; Minoru Matsubara; Sayo Kobayashi; Hiroyuki Okada; Kazuhide Yamamoto
BACKGROUND AND STUDY AIMS Endoscopic submucosal dissection (ESD) is being increasingly used for superficial esophageal cancers. However, esophageal ESD is technically difficult, time consuming, and less safe compared with endoscopic mucosal resection (EMR). To perform ESD safely and more efficiently, various types of knives have been developed. This study compared the efficacy of our newly developed device, Mucosectom2, with that of conventional devices for esophageal ESD. PATIENTS AND METHODS Between May 2007 and February 2011, ESD was performed for 172 esophageal lesions. Of these, 120 lesions were treated by conventional devices only, whereas 52 lesions were treated by conventional devices and the Mucosectom2. Procedure time, en bloc and R0 resection rates, and adverse events were retrospectively compared between the conventional and Mucosectom2 groups. RESULTS The median procedure time was 48.0 minutes in the conventional group and 21.5 minutes in the Mucosectom2 group; the procedure time was significantly shorter in the Mucosectom2 group than in the conventional group (P < 0.0001). The en bloc and R0 resection rates were lower in the conventional group than those in the Mucosectom2 group, although these differences were not significant. The rate of exposure of the muscle layer in the Mucosectom2 group was significantly lower than in the conventional group (P = 0.04). The rates of perforation and postoperative bleeding were not significantly different between the two groups. CONCLUSIONS This feasibility study suggests that, compared with conventional ESD devices, the Mucosectom2 may decrease the time required for esophageal ESD. Although our groups appeared comparable, they were studied at different times. Endoscopic expertise and endoscope quality may have differed during these periods, thereby affecting the results of our study. A prospective trial is therefore required to confirm our results.
Gastrointestinal Endoscopy | 2016
Tatsuhiro Gotoda; Hiroyuki Okada; Keisuke Hori; Yoshiro Kawahara; Masaya Iwamuro; Makoto Abe; Yoshiyasu Kono; Kou Miura; Hiromitsu Kanzaki; Masahide Kita; Seiji Kawano; Kazuhide Yamamoto
BACKGROUND AND AIMS Although the usefulness of propofol sedation during endoscopic submucosal dissection (ESD) for gastric neoplasms was reported previously, information is limited on its use in elderly patients. We investigated the safety and efficacy of propofol sedation with a target-controlled infusion (TCI) pump and bispectral index (BIS) monitoring system (TCI/BIS system) in elderly patients during gastric ESD. METHODS Included were 413 consecutive gastric ESD procedures involving 455 lesions (379 patients) performed in patients under propofol sedation with a TCI/BIS system between October 2009 and September 2013. Patients were divided into 3 groups: group A, age <70 years (n = 162); group B, age ≥70 and <80 years (n = 171); and group C, age ≥80 years (n = 80). We compared the propofol dose and adverse events (eg, hypotension and hypoxemia) during ESD. RESULTS Older groups required a lower target concentration of propofol (group A: median 2.1 μg/mL [interquartile range (IQR), 1.9-2.3]; group B: median 1.6 μg/mL [IQR, 1.3-1.8]; and group C: median 1.4 μg/mL [IQR, 1.2-1.6]; P < .0001). Hypotension tended to occur in the younger group, and hypoxemia occurred at a significantly higher rate in the older groups, although the number of cases was small. Low preoperative systolic blood pressure (≤125 mm Hg) was associated with hypotension (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.12-2.70; P = .013) and abnormal pulmonary function was associated with hypoxemia in groups B and C (OR, 4.54; 95% CI, 1.01-31.5; P = .048). CONCLUSIONS Elderly patients required lower doses of propofol with the TCI/BIS system than younger patients. Attention to hypoxemia is necessary in elderly patients, particularly patients with abnormal pulmonary function.
Internal Medicine | 2015
Yasushi Yamasaki; Junichiro Nasu; Kou Miura; Yoshiyasu Kono; Hiromitsu Kanzaki; Keisuke Hori; Takehiro Tanaka; Masahide Kita; Takao Tsuzuki; Minoru Matsubara; Seiji Kawano; Yoshiro Kawahara; Masahiro Tabata; Hiroyuki Okada; Kazuhide Yamamoto
Composite tumors in the stomach composed of adenocarcinoma and neuroendocrine carcinoma are rare. We herein report a case of intramucosal gastric mixed adenoneuroendocrine carcinoma (MANEC) that was treated with endoscopic submucosal dissection (ESD). A 77-year-old man who had previously received ESD for early gastric adenocarcinoma underwent esophagogastroduodenoscopy for screening, which showed a depressed lesion on the lesser curvature of the antrum. The tumor was removed en bloc via ESD and pathologically diagnosed as MANEC. The tumor was located within the mucosal layer, and no lymphovascular invasion was evident. Seven months after the ESD procedure, the patient is currently feeling well without recurrence or metastasis.
Internal Medicine | 2015
Hisashi Ishikawa; Masaya Iwamuro; Hiroyuki Okada; Keisuke Hori; Masahide Kita; Seiji Kawano; Yoshiro Kawahara; Takehiro Tanaka; Eisei Kondo; Tadashi Yoshino; Kazuhide Yamamoto
A 36-year-old Japanese woman presented with extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) in the stomach. The gastric lesions only partially improved after eradication therapy for Helicobacter pylori. A fluorescence in situ hybridization analysis revealed no fusion genes of API2-MALT1, although trisomy of chromosome 18 was identified. Radiation therapy was initiated to treat the gastric lymphoma lesions, resulting in complete remission. However, MALT lymphoma recurred in the stomach 16 months later. This case indicates that intensive follow-up is required for MALT lymphoma associated with chromosomal aberrations in order to detect early relapse.
Gut and Liver | 2016
Yoshiyasu Kono; Hiroyuki Okada; Ryuta Takenaka; Ko Miura; Hiromitsu Kanzaki; Keisuke Hori; Masahide Kita; Takao Tsuzuki; Seiji Kawano; Yoshiro Kawahara; Kazuhide Yamamoto
Background/Aims The interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and Helicobacter pylori remains controversial. We retrospectively investigated whether H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users. Methods From January 2010 to December 2013, a total of 245 long-term NSAID (including low-dose aspirin) users who had undergone an esophagogastroduodenoscopy and had been evaluated for H. pylori infection were enrolled at Okayama University Hospital and Tsuyama Chuo Hospital. The degree of gastric mucosal injury was assessed according to the modified Lanza score (MLS). Severe gastric mucosal injury was defined as an MLS ≥4. Univariate and multivariate logistic regression analyses were performed. Results In the univariate analysis, age ≥75 years (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.3 to 4.2), H. pylori-positivity (OR, 2.0; 95% CI, 1.2 to 3.5), and the concomitant use of proton pump inhibitors (PPIs) (OR, 0.48; 95% CI, 0.26 to 0.86) were significantly associated with severe gastric mucosal injury. The multivariate analysis was adjusted by age and sex and demonstrated that H. pylori-positivity (OR, 1.8; 95% CI, 1.0 to 3.3) and the concomitant use of PPIs (OR, 0.53; 95% CI, 0.28 to 0.99) significantly contributed to severe gastric mucosal injury. Conclusions H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users.
Digestion | 2016
Ko Miura; Hiroyuki Okada; Yoshiyasu Kouno; Hiromitsu Kanzaki; Masaya Iwamuro; Keisuke Hori; Masahide Kita; Seiji Kawano; Yoshiro Kawahara; Takehiro Tanaka; Hiroyuki Yanai
Background/Aims: Patients who are Helicobacter pylori antibody negative and have normal pepsinogen (PG) levels (group A of ABC (D) stratification) are considered unlikely to develop gastric cancer. This study aimed to clarify the involvement (uninfection, present infection or previous infection) of H. pylori in group A patients with early gastric cancer who underwent endoscopic submucosal dissection (ESD) by examining their background gastric mucosa endoscopically and histologically. Methods: This study included 166 patients with gastric cancer who were treated by ESD. Patients were classified according to PG levels and H. pylori antibody titers. Three biopsies (greater curvature of the antrum, lesser curvature of the middle corpus and greater curvature of the middle corpus) from group A were histologically analyzed and compared with those of groups B, C, D and after eradication). Results: In group A (34 patients), 32 patients had endoscopic atrophy (group A′). Histological neutrophil activity, chronic inflammation and atrophy scores were lower in group A′ than in other groups. Group A′ scores were similar to those of the after eradication group. Conclusion: Most of the group A patients with early gastric cancer were not uninfected with H. pylori, but had previous infections, thus carrying carcinogenic risk.
Internal Medicine | 2015
Masaya Iwamuro; Hiroyuki Okada; Takehiro Tanaka; Keisuke Hori; Masahide Kita; Seiji Kawano; Yoshiro Kawahara; Kazuhide Yamamoto
A 78-year-old Japanese man underwent routine esophagogastroduodenoscopy, during which a reddish, flat elevated lesion was observed in the middle third of the esophagus. A bright red area of protrusion appeared in the center of the elevated lesion three months later, and the protruded nodule grew to be a blood blister six months after the initial endoscopy examination. The morphology of the lesion changed from a protruded nodule to a mass with two humps that subsequently returned to a single hump during the three-year observation period. A histological diagnosis of pyogenic granuloma was made based on a biopsy performed at six months. This report illustrates a rare case of an esophageal pyogenic granuloma presenting with a unique endoscopic appearance and morphologic changes. Endoscopic ultrasonography images are also presented.
Case Reports in Medicine | 2015
Masaya Iwamuro; Takao Tsuzuki; Shogen Ohya; Hiroyuki Okada; Takehiro Tanaka; Keisuke Hori; Masahide Kita; Seiji Kawano; Yoshiro Kawahara; Kazuhide Yamamoto
A 32-year-old Japanese man presented with a gastric submucosal tumor. Esophagogastroduodenoscopy showed a sessile submucosal tumor measuring approximately 10 mm in diameter on the greater curvature of the gastric antrum. Endoscopic ultrasonography examination revealed a solid tumor with a diameter of 11.8 mm, which was located in the deep mucosal and submucosal layers. The internal echogenicity was homogenous and hypoechoic. Biopsy examinations were performed twice but were not diagnostic since only the intact mucosal layer was obtained. The patient was subsequently diagnosed with ectopic pancreas in the stomach by endoscopic submucosal dissection (ESD). This case underscores the usefulness of the ESD technique for the pathological diagnosis of gastric submucosal tumors.
Oncotarget | 2018
Masahide Kita; Kenji Yokota; Chihiro Kageyama; Susumu Take; Kazuyoshi Goto; Yoshiro Kawahara; Osamu Matsushita; Hiroyuki Okada
Helicobacter pylori infections cause gastritis and affect systemic immune responses; however, no direct association between immune cells and stomach bacteria has yet been reported. The present study investigated DEC205-mediated phagocytosis of H. pylori and the role of DEC205-positive macrophages in the human gastric mucosa. DEC205 mediated phagocytosis of H. pylori was detected immunocytochemically in PMA-stimulated macrophages differentiated from NOMO1 cells. Expression of DEC205 mRNA in peripheral blood mononuclear cells (PBMCs) from H. pylori-infected patients was analyzed following stimulation with H. pylori cell lysate. We found that anti-DEC205 antibodies inhibited phagocytosis of H. pylori. The number of cells double-positive for DEC205 and CD14 in human gastric mucosa was higher in H. pylori-infected patients. DEC205-positive macrophages invaded the extracellular space between epithelial cells within gastric pits. In addition, DEC205 mRNA expression was upregulated in human PBMCs stimulated with H. pylori lysate. These findings suggest DEC205-expressing macrophages are important for recognition of H. pylori in human gastric mucosa, which affects systemic immunity.
Digestive Diseases and Sciences | 2017
Yoshiyasu Kono; Minoru Matsubara; Tatsuya Toyokawa; Ryuta Takenaka; Seiyu Suzuki; Junichirou Nasu; Masao Yoshioka; Masahiro Nakagawa; Motowo Mizuno; Hiroyuki Sakae; Makoto Abe; Tatsuhiro Gotoda; Ko Miura; Hiromitsu Kanzaki; Masaya Iwamuro; Keisuke Hori; Takao Tsuzuki; Masahide Kita; Seiji Kawano; Yoshiro Kawahara; Hiroyuki Okada
The article, Multicenter Prospective Study on the Safety of Upper Gastrointestinal Endoscopic Procedures in Antithrombotic Drug Users by Yoshiyasu Kono, Minoru Matsubara, Tatsuya Toyokawa, Ryuta Takenaka, Seiyu Suzuki Junichirou Nasu, Masao Yoshioka, Masahiro Nakagawa, Motowo Mizuno, Hiroyuki Sakae, Makoto Abe, Tatsuhiro Gotoda, Ko Miura, Hiromitsu Kanzaki, and Masaya Iwamuro published online on January 3, 2017, in Digestive Diseases and Sciences, contains an error in Table 5. A revised version of Table 5 is below. The number of postoperative bleeding after EMR/ESD in multiple antithrombotic drug users contained an error.