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Featured researches published by Akitoshi Ikegami.


Pancreatology | 2002

A case of autoimmune pancreatitis responding to steroid therapy

Takeshi Saito; Shigeki Tanaka; Hitoshi Yoshida; Tsunao Imamura; Junichi Ukegawa; Tetsuya Seki; Akitoshi Ikegami; Fuyuhiko Yamamura; Tetsuya Mikami; Yuji Aoyagi; Junichi Niikawa; Keiji Mitamura

We report a case of autoimmune pancreatitis without obvious evidence of autoimmunological participation, which responded well to steroid treatment and provided histologic and radiographic evidence for this improvement. A 68-year-old woman presented abdominal fullness, diffuse pancreatic swelling on abdominal computed tomography and ultrasonography, and diffuse narrowing of the main pancreatic duct on endoscopic retrograde pancreatography. Transgastric aspiration needle biopsy of the body of the pancreas performed under endoscopic ultrasonography showed severe atrophy of acinar cells, infiltration of T lymphocytes. She was diagnosed as having autoimmune pancreatitis without obvious evidence of autoimmunological participation. Administration of 30 mg/day of predonisolone was started. Computed tomography showed marked improvement of the diffuse swelling of the pancreas, and endoscopic retrograde pancreatograpy showed amelioration of the narrowing of the main pancreatic duct after the start of treatment. Pancreatic tissue obtained by needle biopsy after the start of treatment with predonisolone revealed marked histologic improvement, including amelioration of the fibrosis, and infiltration of inflammatory lymphocytes, and a substantial increase in the number of pancreatic acinar cells. The present report is the first to demonstrate histologic recovery of autoimmune pancreatitis after steroid therapy.


Journal of Gastroenterology | 2002

Significance of measurement of high-sensitivity C-reactive protein in acute pancreatitis

Tsunao Imamura; Shigeki Tanaka; Hitoshi Yoshida; Katsuya Kitamura; Akitoshi Ikegami; Akira Takahashi; Junichi Niikawa; Keiji Mitamura

Background: Determination of the severity of acute pancreatitis is difficult in the early phase after onset, and we often encounter difficulties in making decisions to initiate intensive care during the early phase. Therefore, there is real need for a simple and inexpensive method that can precisely evaluate the severity of acute pancreatitis. Methods: In the present study, we measured serum C-reactive protein (CRP) levels in 20 patients with acute pancreatitis, using a high-sensitivity CRP (hs-CRP) assay method. Results: CRP levels were as low as 1.0, 0.4, and 0.3 mg/dl in cases 2, 3, and 9, respectively, with severe acute pancreatitis. These three patients were hospitalized within 24 h after the onset of pancreatitis. Cases 2, 3, and 9 showed high hs-CRP levels, of 209 000, 68 600, and 154 000 ng/ml, respectively, and their interleukin (IL)-6 levels were above 500 pg/ml. The mean hs-CRP level was 222 760 ± 32 197 ng/ml in patients with severe acute pancreatitis and 22 798 ± 8216 ng/ml in patients with mild to moderate pancreatitis, with a significantly higher level in the severe cases. Cases 14, 16, and 20, with mild to moderate pancreatitis, had hs-CRP levels of 83 400, 1800, and 55 400 ng/ml, respectively. Conclusions: Measurement of hs-CRP levels is a simple and inexpensive method. The hs-CRP levels were found to significantly increase in the early phase of severe acute pancreatitis, suggesting that hs-CRP could possibly serve as an early indicator of the progression of acute pancreatitis into a serious state.


Pancreas | 2000

Involvement of calmodulin and protein kinase C in cholecystokinin release by bombesin from STC-1 cells.

Akira Takahashi; Shigeki Tanaka; Yoshikatsu Miwa; Hitoshi Yoshida; Akitoshi Ikegami; Junichi Niikawa; Keiji Mitamura

The mouse intestinal neuroendocrine tumor cell line STC-1 secretes cholecystokinin (CCK) and other hormones. We investigated the role of Ca2+, calmodulin (CaM), and protein kinase C (PKC) in the regulation of CCK release from STC-1 cells. Phorbol 12-myristate 13-acetate (TPA) significantly stimulated CCK release. Staurosporine significantly inhibited CCK release from STC-1 cells stimulated by TPA in a dose-dependent manner. The absence of extracellular calcium completely inhibited CCK release from TPA-stimulated STC-1 cells. Neurotensin did not stimulate CCK release from these cells. W-7, a CaM antagonist, reduced CCK release from STC-1 cells stimulated by bombesin in a dose-dependent manner. These findings suggest that CaM and PKC play an important role in the regulation of CCK release from STC-1 cells stimulated by bombesin.


World Journal of Gastroenterology | 2015

0.025-inch vs 0.035-inch guide wires for wire-guided cannulation during endoscopic retrograde cholangiopancreatography: A randomized study.

Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Yoshiki Sato; Tomoyuki Iwata; Tomohiro Nomoto; Akitoshi Ikegami; Hitoshi Yoshida

AIM To compare the clinical outcomes between 0.025-inch and 0.035-inch guide wires (GWs) when used in wire-guided cannulation (WGC). METHODS A single center, randomized study was conducted between April 2011 and March 2013. This study was approved by the Medical Ethics Committee at our hospital. Informed, written consent was obtained from each patient prior to study enrollment. Three hundred and twenty-two patients with a naïve papilla of Vater who underwent endoscopic retrograde cholangiopancreatography (ERCP) for the purpose of selective bile duct cannulation with WGC were enrolled in this study. Fifty-three patients were excluded based on the exclusion criteria, and 269 patients were randomly allocated to two groups by a computer and analyzed: the 0.025-inch GW group (n = 109) and the 0.035-inch GW group (n = 160). The primary endpoint was the success rate of selective bile duct cannulation with WGC. Secondary endpoints were the success rates of the pancreatic GW technique and precutting, selective bile duct cannulation time, ERCP procedure time, the rate of pancreatic duct stent placement, the final success rate of selective bile duct cannulation, and the incidence of post-ERCP pancreatitis (PEP). RESULTS The primary success rates of selective bile duct cannulation with WGC were 80.7% (88/109) and 86.3% (138/160) for the 0.025-inch and the 0.035-inch groups, respectively (P = 0.226). There were no statistically significant differences in the success rates of selective bile duct cannulation using the pancreatic duct GW technique (46.7% vs 52.4% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.884) or in the success rates of selective bile duct cannulation using precutting (66.7% vs 63.6% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.893). The final success rates for selective bile duct cannulation using these procedures were 92.7% (101/109) and 97.5% (156/160) for the 0.025-inch and 0.035-inch groups, respectively (P = 0.113). There were no significant differences in selective bile duct cannulation time (median ± interquartile range: 3.7 ± 13.9 min vs 4.0 ± 11.2 min for the 0.025-inch and 0.035-inch groups, respectively; P = 0.851), ERCP procedure time (median ± interquartile range: 32 ± 29 min vs 30 ± 25 min for the 0.025-inch and 0.035-inch groups, respectively; P = 0.184) or in the rate of pancreatic duct stent placement (14.7% vs 15.6% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.832). The incidence of PEP was 2.8% (3/109) and 2.5% (4/160) for the 0.025-inch and 0.035-inch groups, respectively (P = 0.793). CONCLUSION The thickness of the GW for WGC does not appear to affect either the success rate of selective bile duct cannulation or the incidence of PEP.


Journal of Gastroenterology | 2003

Effect of IS-741 on ethionine-induced acute pancreatitis in rats: relation to pancreatic acinar cell regeneration

Tsunao Imamura; Junichi Niikawa; Katsuya Kitamura; Akira Takahashi; Akitoshi Ikegami; Hitoshi Yoshida; Shigeki Tanaka; Keiji Mitamura

Background: Tissue destruction arising from neutrophil infiltration of the pancreas and other organs in acute pancreatitis is supposed to be suppressed by IS-741. We studied the effect of IS-741 on acute pancreatitis induced by DL-ethionine in rats. Methods: Rats fed with a low protein diet for 11 days received daily intraperitoneal administration of DL-ethionine (20 mg/100 g) for the last 4 days of the diet. To evaluate the therapeutic effect on ethionine-induced pancreatitis, IS-741 (10 mg/kg s.c.) was administered every 8 h beginning after the second ethionine injection (IS group). An equal volume of saline was used for control rats as alternative to IS-741 (control group). The rats were killed 1, 3, 5, and 7 days after the last injection of ethionine. Blood was collected to measure concentrations of the inflammatory cytokine, interleukin-8. Histologic and biochemical examinations of the pancreas were performed. The pancreatic weight, DNA content, and protein levels were determined. The pancreas was histologically examined. Results: Pancreatic tissue in the control group showed marked infiltration of inflammatory cells, and acinar cell necrosis was widespread 1 day after the last injection of ethionine (day 1). The severity of acute pancreatitis was alleviated in rats treated with IS-741 (IS group). Pancreatic wet weight and DNA content in the IS group were higher than those in the control group on day 1. Pancreatic protein level per DNA in the IS group was higher than that in the control group on day 7. The plasma interleukin-8 level in the control group was higher than that in the IS group on day 5. Conclusions: Therapeutic administration of IS-741 ameliorated ethionine-induced acute pancreatitis in rats, and IS-741 could be a useful drug to treat patients with severe acute pancreatitis.


World Journal of Gastrointestinal Endoscopy | 2014

Evaluation of diagnostic cytology via endoscopic naso-pancreatic drainage for pancreatic tumor

Tomoyuki Iwata; Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Yoshiki Sato; Tomohiro Nomoto; Akitoshi Ikegami; Hitoshi Yoshida

AIM To evaluate the usefulness of cytology of the pancreatic juice obtained via the endoscopic naso-pancreatic drainage tube (ENPD-C). METHODS ENPD was performed in cases where a diagnosis could not be made other than by using endoscopic retrograde cholangiopancreatography and in cases of pancreatic neoplasms or cystic tumors, including intraductal papillary mucinous neoplasm (IPMN) suspected to have malignant potential. 35 patients (21 males and 14 females) underwent ENPD between January 2007 and June 2013. The pancreatic duct was imaged and the procedure continued in one of ENPD-C or ENPD-C plus brush cytology (ENPD-BC). We checked the cytology result and the final diagnosis. RESULTS The mean patient age was 69 years (range, 48-86 years). ENPD-C was performed in 24 cases and ENPD-C plus brush cytology (ENPD-BC) in 11 cases. The ENPD tube was inserted for an average of 3.5 d. The final diagnosis was confirmed on the basis of the resected specimen in 18 cases and of follow-up findings at least 6 mo after ENPD in the 18 inoperable cases. Malignancy was diagnosed in 21 cases and 14 patients were diagnosed as having a benign condition. The ratios of class V/IV:III:II/I findings were 7:7:7 in malignant cases and 0:3:11 in benign cases. The sensitivity and specificity for all patients were 33.3% and 100%, respectively. The cytology-positive rate was 37.5% (6/16) for pancreatic cancer. For IPMN cases, the sensitivity and specificity were 33% and 100%, respectively. CONCLUSION Sensitivity may be further increased by adding brush cytology. Although we can diagnosis cancer in cases of a positive result, the accuracy of ENPD-C remains unsatisfactory.


Pediatric Dermatology | 2011

A case of gastrocolic fistula

Jun Arai; Yu Shimozuma; Tomohiro Nomoto; Akitoshi Ikegami; Fumihiko Nozu; Michio Imawari; Yusuke Tajima; Atsushi Sato; Kimiyasu Yamazaki; Koji Otsuka; Takashi Kato; Masahiko Murakami


Pancreas | 2007

THERAPEUTIC PROCEDURE AND PROGNOSIS IN PATIENTS WITH AUTOIMMUNE PANCREATITIS

Shigeki Tanaka; Hitoshi Yoshida; Akitoshi Ikegami; Katsuya Kitamura


The Showa University Journal of Medical Sciences | 2006

Protease-activated Receptor 2 (PAR-2) in Pancreatic Macrophages/monocytes is Involved in Exacerbation of Acute Pancreatitis in Rats

Tadashi Honma; Hitoshi Yoshida; Junichi Niikawa; Shigeki Tanaka; Takahisa Yamazaki; Katsuya Kitamura; Tsunao Imamura; Akitoshi Ikegami; Takeshi Kawaguchi; Michio Imawari


Pancreatology | 2002

26th Annual Meeting of the Pancreatic Society of Great Britain and Ireland

Waldemar Uhl; Matthias B. Schneider; Andrew L. Warshaw; Clement W. Imrie; Claudio Bassi; Colin J. McKay; Paul Georg Lankisch; John M. Fitzpatrick; Ross Carter; Eugene Di Magno; Peter A. Banks; David C. Whitcomb; Christos Dervenis; Charles D. Ulrich; Kat Satake; Paula Ghaneh; Werner Hartwig; Jens Werner; G. P. McEntee; John P. Neoptolemos; Markus W. Büchler; Jens M. Mayer; Hana Algül; Yusuke Tando; Günter Schneider; Hans Weidenbach; Guido Adler; T. Armstrong; E. Walters; S. Varshney

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