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Dive into the research topics where Yuji Imamura is active.

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Featured researches published by Yuji Imamura.


Journal of Gastroenterology | 2002

Long-term results of seton drainage on complex anal fistulae in patients with Crohn's disease

Yoshio Takesue; Hiroki Ohge; Takashi Yokoyama; Yoshiaki Murakami; Yuji Imamura; Taijiro Sueda

Background: The aim of this study was to assess the long-term (greater than 2 years) results of seton drainage on anal fistulae in patients with Crohns disease. Methods: Between September 1990 and September 1999, 32 patients with Crohns disease underwent seton drainage for complex anal fistulae. The median follow-up time in these patients was 62 months (range, 25–133 months). In 10 patients (31.3%), recurrent perineal abscesses occurred with inlying seton drainage, and these were drained by re-insertion of the seton. A Malecot catheter was also inserted in 8 patients with recurrence. Results: The overall success rate of long-term seton usage was 87.5%. The subsequent associated procedure was simple seton removal (n = 9), secondary core-out fistulectomy (n = 7), or lay-open fistulotomy (n = 4). Eleven patients still had the seton in place. Recurrence developed in 3 patients (33%) who underwent simple seton removal and in 2 patients (18.2%) who underwent the secondary core-out procedure or fistulotomy. At the last follow-up examination, continence had not changed in 28 (87.5%) of the 32 patients. No change in continence was experienced by 10 of the 11 patients who underwent secondary fistulotomy or the secondary core-out procedure. Conclusions: Long-term seton drainage for complex anal fistula in Crohns disease is efficacious in both treating sepsis and preserving anal sphincter function. A relatively good result was achieved by the secondary core-out procedure or fistulotomy at the time of seton removal.


Surgery Today | 1997

Postoperative Enteritis Caused by Methicillin-Resistant Staphylococcus aureus

Takashi Kodama; Takahiro Santo; Takashi Yokoyama; Yoshio Takesue; Eiso Hiyama; Yuji Imamura; Yoshiaki Murakami; Hiroaki Tsumura; Kanae Shinbara; Naokuni Tatsumoto; Yuichirou Matsuura

We examined the clinical features of 14 men (mean age 72 years) with postoperative enteritis caused by methicillin-resistantStaphylococcus aureus (MRSA). The patients had all undergone surgery for the treatment of digestive diseases and had received antibiotic prophylaxis consisting of an extended-spectrum cephem. Diarrhea appeared a mean of 3.3 days postoperatively and lasted for 5 days on average. In severe cases organ insufficiency was involved. Coagulase-positive staphylococci were the predominant organisms isolated from watery diarrhea. In 13 of 14 patients, coagulase type II isolates producing enterotoxins A, C and toxic shock syndrome toxin-1 (TSST-1) withenterotoxin A, C, andtst genes were isolated. These strains were sensitive to vancomycin and arbekacin; however, they were highly resistant to many other antibiotics. We also investigated the effects of a glucocorticoid hormone and gamma globulin on production of tumor necrosis factor-α (TNF-α) and interleukin-2 (IL-2) obtained from healthy volunteers. TNF-α and IL-2 production was enhanced by TSST-1 and the supernatant of Iscove-modified dulbecco medium, in which coagulase type II isolates producing enterotoxins A, C and TSST-1 with enterotoxin A, C were cultured for 24h. Both glucocorticoid hormone and gama globulin suppressed TNF-α and IL-2 production, thus suggesting that these drugs may be effective in treating postoperative MRSA enteritis.


Surgery Today | 2001

Kupffer Cell Function in Ischemic and Nonischemic Livers After Hepatic Partial Ischemia/Reperfusion

Atsushi Nakamitsu; Eiso Hiyama; Yuji Imamura; Yuichiro Matsuura; Takashi Yokoyama

Abstract Hepatic partial ischemic/reperfusion (I/R) injury, in which ischemic and nonischemic areas of the liver are likely to respond to each other after reperfusion, often occurs following hepatobiliary surgical procedures. Kupffer cells (KCs) are considered to play a major role in hepatic I/R injury. To study the activation of KCs in ischemic and nonischemic liver tissues following hepatic I/R, we investigated the superoxide generation and proinflammatory cytokine production of KCs in both liver parts in a rat model of partial hepatic I/R injury. KC superoxide generation in the ischemic and nonischemic lobes was upregulated 6 and 24 h after reperfusion, respectively, and then accelerated. The production of interleukin-1β (IL-1β) by KCs in the ischemic lobes increased during the early and late phases, 6 h and 48–72 h after reperfusion, respectively. A late increase in IL-1β production was also observed in the nonischemic lobes. Production of tumor necrosis factor-α (TNF-α) increased 6–24 h after reperfusion in both lobes. Upregulation of IL-1β mRNA in the ischemic lobes preceded the upregulation of TNF-α mRNA in both lobes. The hepatic partial I/R process results in activation of KCs in ischemic and nonischemic areas of the liver. The KCs are activated during the early phase after reperfusion in the ischemic areas, followed by activation in both the ischemic and nonischemic areas. This could be a cause of liver dysfunction after partial hepatic I/R during surgery.


Journal of Gastroenterology | 2000

Progression of primary biliary cirrhosis after proctocolectomy for ulcerative colitis.

Hiroki Ohge; Yoshio Takesue; Takashi Yokoyama; Eiso Hiyama; Yoshiaki Murakami; Yuji Imamura; Fumio Shimamoto; Yuichiro Matsuura

Abstract: We report a case of progression of primary biliary cirrhosis (PBC) after proctocolectomy for ulcerative colitis. A 43-year-old woman underwent a total proctocolectomy after being diagnosed with ulcerative colitis. In the course of the preoperative investigation, liver function test results were within the normal range. Four months after the proctocolectomy, the patient showed a high level of alkaline phosphatase (2398 IU/l) and a positive anti-mitochondrial antibody titer (>1 : 160). There were no associated symptoms. A liver biopsy demonstrated expansion of all portal areas by infiltrates of lymphocytes and histiocytes. These appearances indicated chronic biliary disease and were compatible with PBC. The association of PBC and ulcerative colitis is rare. However, a review of the recent literature suggests that PBC and ulcerative colitis may be associated; this combination should be kept in mind.


Journal of Gastroenterology | 2000

Strictureplasty for short duodenal stenosis in Crohn's disease

Yoshio Takesue; Takashi Yokoyama; Shinji Akagi; Hiroki Ohge; Yoshiaki Murakami; Yuji Imamura; Kenichiro Uemura; Tetsuya Kanehiro; Yuichiro Matsuura

Abstract: Involvement of the gastroduodenum is extremely rare in Crohns disease. For obstructing duodenal Crohns disease, bypass procedures have traditionally been selected. However, more recently, strictureplasty has become an acceptable surgical option. We treated two Crohns disease patients with short proximal duodenal stenosis, using Finney-type strictureplasty. Their postoperative courses were uneventful and they have remained asymptomatic during follow-up periods of more than 5 years, and 4 months, respectively. Owing to the good clinical results of our two patients, we consider strictureplasty to be indicated for short proximal duodenal stenosis in Crohns disease.


Surgery Today | 1992

Anomalous arrangement of the pancreaticobiliary ductal system without dilatation of the biliary tract.

Yoshiaki Murakami; Takashi Kodama; Yoshio Takesue; Mitsuaki Okita; Atsushi Nakamitsu; Yuji Imamura; Hitoshi Sewake; Hiroaki Tsumura; Katsunari Miyamoto; Yuichiro Matsuura; Takashi Yokoyama

A rare case of anomalous arrangement of the pancreaticobiliary ductal system without dilatation of the biliary tract (AAPBDS without DBT) associated with mucosal dysplasia of the biliary duct is described herein. A 53 year old male with a long history of diarrhea and right upper abdominal pain was diagnosed as having AAPBDS without DBT by endoscopic retrograde cholangiopancreatography and other examinations. Excision of the gallbladder and biliary duct with a Roux-en-Y hepatico-jejunostomy was performed and subsequent pathological examination of the surgical specimens showed mucosal hyperplasia of the gall-bladder and mucosal dysplasia of the biliary duct. Considering the dysplastic changes of the biliary duct as seen in our case, and the high incidence of AAPBDS without DBT developing into carcinoma of the biliary duct, being 12.2 per cent, we suggest that pancreaticobiliary ductal diversion with excision of the gall-bladder and biliary duct should also be performed for AAPBDS without DBT. However, further pathological investigations concerning the excised biliary duct in AAPBDS without DBT will be need to be carried out.


Surgery Today | 1993

Mucin-producing pancreatic tumors: A study of nuclear DNA content by flow cytometry

Yoshiaki Murakami; Takashi Yokoyama; Takashi Kodama; Yoshio Takesue; Mitsuaki Okita; Atsushi Nakamitsu; Yuji Imamura; Takahiro Santo; Hiroaki Tsumura; Katsunari Miyamoto; Yuichiro Matsuura

Nuclear DNA content in eight surgically resected mucin-producing pancreatic tumors (MPPT) consisting of two mucinous intraductal adenocarcinomas (MIDAC), two mucinous intraductal adenomas (MIDA), one mucinous cystadenocarcinoma (MCAC), and three mucinous cystadenomas (MCA) were measured by flow cytometry using paraffin-embedded tissue samples. The technique of Shutte was used for the preparation of paraffin-embedded tissue into single dissociated nuclei, while the method of Vindelov was used for staining the isolated nuclei with propidium iodine. Clinicopathologically, the four patients with MIDAC or MIDA were all male and had cystic lesions with a dilated pancreatic duct at the head of the pancreas, while the four patients with MCAC or MCA were all females and had cystic tumors at either the body or tail of the pancreas. All eight patients with MPPT had no metastasis to the regional lymph nodes and were all still alive without recurrence. In an analysis of nuclear DNA content, seven of eight patients had DNA diploid tumors while one patient with a MIDAC perforating the duodenum and choledochus had a DNA aneuploid tumor. Thus, these findings suggest that DNA diploid patterns in MPPT might be associated with a favorable prognosis in MPPT although some patients whose MPPT invaded the surrounding organs might have DNA aneuploid tumors.


Diseases of The Colon & Rectum | 2001

Gut transit time after ileal pouch-anal anastomosis using a radiopaque marker

Yoshio Takesue; Yoshihiro Sakashita; Shinji Akagi; Yoshiaki Murakami; Hiroki Ohge; Yuji Imamura; Yoko Horikawa; Takashi Yokoyama

PURPOSE: The aim of this study was to determine the contribution of gastrointestinal motility to bowel function and the pathogenesis of pouchitis after ileal pouch-anal anastomosis. METHODS: Gastrointestinal transit time was assessed by a radiopaque marker technique in 32 patients with ulcerative colitis. RESULTS: Small intestinal transit time and pouch emptying time were 4.1±2 hours and 4.1±2.5 hours, respectively. There was no significant difference in pouch emptying time between patients with and without pouchitis. When only patients with acute pouchitis that responded to metronidazole were analyzed, there was a trend toward a prolonged pouch emptying time compared with those without pouchitis (P=0.095). Whole gut transit time was inversely correlated with 24-hour stool frequency in patients without pouchitis (r=−0.63,P<0.005). In the analysis of regional transit time, only small intestinal transit time was inversely correlated with 24-hour stool frequency (r=−0.472,P<0.05). Significant prolongation of small intestinal transit time was demonstrated in patients over a period of 41 months (the median time) after ileostomy closure compared with those whose pouches had been functioning for 6 to 41 months (5.4±1.7 hoursvs. 3.1±1.3 hours,P<0.005). CONCLUSIONS: There was an association between small intestinal motility and bowel frequency. Further investigation is necessary in the pathogenesis of acute pouchitis regarding the relationship between delayed pouch emptying and subsequent development of mucosal inflammation.


Surgery Today | 1997

Influence of ileal pouch capacity and anal sphincteric function on the clinical outcome after ileal pouch-anal anastomosis

Yoshio Takesue; Takashi Yokoyama; Takashi Kodama; Yoshiaki Murakami; Yuji Imamura; Yuichiro Matsuura

This study was designed to determine the influence of ileal pouch capacity and anal sphincteric function on the clinical outcome after ileal pouch-anal anastomosis. A total of 24 patients who had undergone ileal pouch-anal anastomosis (J pouch) for ulcerative colitis were studied. The 24-hour stool frequency was found to be inversely correlated with the sensitivity threshold volume (STV), maximal tolerance volume (MTV), and distensibility, but was independent of the maximal resting pressure and maximal squeeze pressure. Patients experiencing nocturnal fecal incontinence had maximal resting pressures that were significantly lower than those of nocturnally continent patients. Among the patients with fecal incontinence, those with frequent soiling had lower resting pressures, STV, and distensibility than the patients with intermittent spotting. In addition, the STV in patients needing nocturnal evacuation were lower than those of patients who did not evacuate after falling asleep. The conclusions are as follows. Both stool frequency and the need for nocturnal pouch evacuation correlated directly with pouch volume. Anal incontinence was more common in patients with low internal sphincteric function. In addition, frequent and gross nocturnal incontinent patients demonstrate a worse function in both the anal sphincter and reservoir than those with intermittent spotting.


World Journal of Gastroenterology | 2015

Successful treatment of conversion chemotherapy for initially unresectable synchronous colorectal liver metastasis

Kenta Baba; Akihiko Oshita; Mohei Kohyama; Satoshi Inoue; Yuta Kuroo; Takuro Yamaguchi; Hiroyuki Nakamura; Yoichi Sugiyama; Tatsuya Tazaki; Masaru Sasaki; Yuji Imamura; Yutaka Daimaru; Hideki Ohdan; Atsushi Nakamitsu

A 72-year-old woman with a sigmoid colon cancer and a synchronous colorectal liver metastasis (CRLM), which involved the right hepatic vein (RHV) and the inferior vena cava (IVC), was referred to our hospital. The metastatic lesion was diagnosed as initially unresectable because of its invasion into the confluence of the RHV and IVC. After she had undergone laparoscopic sigmoidectomy for the original tumor, she consequently had 3 courses of modified 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) plus cetuximab. Computed tomography revealed a partial response, and the confluence of the RHV and IVC got free from cancer invasion. After 3 additional courses of mFOLFOX6 plus cetuximab, preoperative percutaneous transhepatic portal vein embolization (PTPE) was performed to secure the future remnant liver volume. Finally, a right hemihepatectomy was performed. The postoperative course was uneventful. The patient was discharged from the hospital on postoperative day 13. She had neither local recurrence nor distant metastasis 18 mo after the last surgical intervention. This multidisciplinary strategy, consisting of conversion chemotherapy using FOLFOX plus cetuximab and PTPE, could contribute in facilitating curative hepatic resection for initially unresectable CRLM.

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Yoshio Takesue

Hyogo College of Medicine

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Yoshiaki Murakami

Memorial Hospital of South Bend

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Yoshiaki Murakami

Memorial Hospital of South Bend

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