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Dive into the research topics where Hiroaki Tsumura is active.

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Featured researches published by Hiroaki Tsumura.


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 | 1993

A study on postoperative enteritis caused by methicillin-resistant Staphylococcus aureus

Yoshio Takesue; Takashi Yokoyama; Takashi Kodama; Takahiro Santou; Atsushi Nakamitsu; Yoshiaki Murakami; Yuugi Imamura; Katsunari Miyamoto; Mitsuaki Okita; Hiroaki Tsumura; Toshiaki Hirata; Yuichiro Matsuura

We investigated the production of staphylococcal enterotoxin (SE) with respect to coagulase types by methicillin-resistant Staphylococcus aureus (MRSA). A total of 138 strains of MRSA, which were isolated from clinical materials in the surgical ward between 1983 and 1990, were studied. Coagulase type IV strains produced SE A only, whereas coagulase type II strains were classified into four groups by SE production: SE B producing strains (32.7%), SE C producing strains (29.8%), SE B and C coproducing strains (12.5%), and SE A and C coproducing strains (25.0%). Almost all of the organisms (nine of ten) which were isolated from the feces of patients with MRSA enteritis were SE A and C coproducing strains. The coincidence in time of the prevalence of MRSA enteritis and the isolation SE A and C coproducing strains also demonstrated that these strains caused MRSA enteritis. Although SE C producing strains and SE A and C coproducing strains were simultaneously prevalent in 1990, the former tended to be sensitive while the latter tended to be resistant to minocycline. Considering the variety of antibiotic sensitivity in coagulase type II strains, it is thus considered to be of critical importance for epidemiologic purposes to further characterize isolates by SE typing.


Gastrointestinal Endoscopy | 2004

An evaluation of laparoscopic cholecystectomy after selective percutaneous transhepatic gallbladder drainage for acute cholecystitis.

Hiroaki Tsumura; Toru Ichikawa; Eiso Hiyama; Tetsuya Kagawa; Masahiro Nishihara; Yoshiaki Murakami; Taijiro Sueda

BACKGROUND The aim of this study was to evaluate the safety and usefulness of laparoscopic cholecystectomy after selective percutaneous transhepatic gallbladder drainage in patients with severe acute cholecystitis and patients with acute cholecystitis and severe comorbid disease. METHODS According to whether percutaneous transhepatic gallbladder drainage was performed before surgery, 133 patients with acute cholecystitis were divided into a percutaneous transhepatic gallbladder drainage group (n=60) and non-percutaneous-transhepatic-gallbladder-drainage group (n=73). Background factors, safety, and postoperative course were retrospectively evaluated and compared between these two groups. RESULTS Compared with the non-percutaneous-transhepatic-gallbladder-drainage group, the percutaneous transhepatic gallbladder drainage group was significantly older (p=0.0009), had a higher frequency of comorbid disease (p=0.0252), and a worse American Society of Anesthesiology classification (p=0.0021). In individual statistical tests, body temperature (p=0.0288), white blood cell count (p=0.0175), and C-reactive protein value (p=0.0022) were significantly elevated in the percutaneous transhepatic gallbladder drainage group; however, for frequency of comorbid disease, body temperature, and white blood cell count, significance was removed by correction for multiple testing of data. There was no significant difference in gender distribution, history of upper abdominal surgery, or body mass index between the two groups. The duration of surgery was marginally but significantly longer in the percutaneous transhepatic gallbladder drainage group (p=0.0414; in a single statistical test; however, that significance was removed by correction for the multiple testing of data). Between the two groups, there was no significant difference in blood loss at surgery, frequency of postoperative complications, rate of conversion to open laparotomy, interval until oral feeding was resumed, and length of postoperative hospital stay. CONCLUSIONS These data suggest that satisfactory outcomes can be achieved with selective pre-operative gallbladder drainage in older and sicker patients with acute cholecystitis.


Gastroenterologia Japonica | 1991

Toxin involvement in methicillin-resistant Staphylococcus aureus enteritis in gastroenterological surgery

Yoshio Takesue; Takashi Yokoyama; Takashi Kodama; Takahiro Santou; Atsushi Nakamitsu; Yoshiaki Murakami; Yuuji Imamura; Katsunari Miyamoto; Mitsuaki Okita; Hiroaki Tsumura; Hideyuki Itaha; Yuichiro Matsuura

SummaryThe authors investigated the production of toxic shock syndrome toxin-1 (TSST-1) and staphylococcal enterotoxins (SE) by Methicillin-resistantStaphylococcus aureus (MRSA) isolates to clarify the pathogenesis of postoperative MRSA enteritis in patients undergoing gastroenterological surgery. Regarding the percentage of TSST-1-producing strains, there was a significant difference between type II MRSA strains (68.8%) and type IV MRSA strains (4.2%). Among type II strains, all those producing staphylococcal entorotoxin (SE) type C (SEC) also produced TSST-1, although other strains that produced SEB without TSST-1 were commonly isolated. Strains producing SEA were potent producers of SE which was considered to be responsible for enteritis. Therefore, we hypothesized that the strains which produced both SEA and SEC tended to cause enteritis associated with TSS-like symptoms owing to the high titer of these toxins.


Journal of Hepato-biliary-pancreatic Surgery | 2008

Patient with perforation caused by emphysematous cholecystitis who showed flare on the skin of the right dorsal lumbar region and intraperitoneal free gas

Tetsuya Kanehiro; Hiroaki Tsumura; Toru Ichikawa; Yuji Hino; Yoshiaki Murakami; Taijiro Sueda

We report an 84-year-old man with perforation caused by emphysematous cholecystitis who showed flare on the skin of the right dorsal lumbar region and intraperitoneal free gas. The patient was admitted for abdominal pain, abdominal swelling, and consciousness disorder 18 days after the onset. Abdominal computed tomography (CT) revealed emphysema in the gallbladder and a small amount of intraperitoneal free gas. Intraoperative findings suggested gangrenous cholecystitis. The gallbladder wall was perforated, and an abscess involving the right subphrenic region, the periphery of the liver and gallbladder, and the right paracolonic groove, was detected. The flare on the body surface may have reflected abscess formation in the right abdominal cavity. Emphysematous cholecystitis induces necrosis and perforation in many patients, and immediate strategies such as emergency surgery are important.


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.


International Journal of Antimicrobial Agents | 2003

Relevance of antimicrobial agent-induced endotoxin release from in vitro cultured Escherichia coli and in vivo experimental infection with Gram-negative bacilli

Hiroaki Tsumura; Eiso Hiyama; Takashi Kodama; Taijiro Sueda; Takashi Yokoyama

In vitro exposure of Gram-negative bacilli (GNB) to antimicrobial agents may induce endotoxin (ET) release, that may cause various reactions in vivo resulting in endotoxic shock. We used the antimicrobial agents, flomoxef (FMOX) and gentamicin (GM), to investigate the kinetics of ET released from in-vitro-cultured Escherichia coli and to examine the ET effect on tumor necrosis factor (TNF) production by macrophages. In a rabbit model of E. coli peritonitis, we measured plasma ET, TNF and blood bacterial counts under the administration of FMOX or GM. In our in vitro experiment, ET levels under FMOX were significantly higher than those under GM, and ET induced TNF production in a dose-dependent manner. However, in vivo, plasma ET, TNF, and blood bacterial counts under antimicrobial agents were significantly lower than those of the controls, and those under FMOX treatment did not differ from those under GM treatment. Thus, ET release may not be a critical problem in GNB infections if appropriate antimicrobial agents are administered.


Surgery Today | 1995

Severity and predicted outcome of postoperative Pseudomonas aeruginosa infections

Takashi Kodama; Takashi Yokoyama; Yoshio Takesue; Mitsuaki Okita; Atsushi Nakamitsu; Eiso Hiyama; Yuji Imamura; Takahiro Santo; Yoshiaki Murakami; Hiroaki Tsumura; Kanae Shinbara; Katsunari Miyamoto; Naokuni Tatsumoto; Yuichirou Matsuura

The severity and predicted outcome of postoperative Pseudomonas aeruginosa (P. aeruginosa) infections (PPAI) was evaluated using a severity scoring system based on a simplification and modification of the APACHE II system. A total of 86 patients in whom P. aeruginosa was isolated from various sources were examined. PPAI developed in 50 patients, resulting in an overall mortality rate of 24%. An increased severity score (SS) correlated with an increased risk of developing PPAI. Thus, PPAI developed in 33% of the patients with an SS of 0–1, in 66.7% of those with an SS of 2–3, and in 100% of those with an SS of 6 or higher. Moreover, the mortality rate of the patients with an initial score of 6 or higher was 50%. The mean (±SD) initial severity score was 5.4±2.9 for survivors and 2.9±2.6 for nonsurvivors (P<0.01). In the patients who subsequently died, the SS remained high throughout the clinical course despite therapy, whereas in the survivors the SS decreased progressively, reflecting a favorable clinical course. These results suggest that our severity scoring system was useful for predicting outcome and monitoring the response of PPAI to therapy.


Digestive Surgery | 2018

Clinical Characteristics and Surgical Treatment for Inguinal Endometriosis in Young Women of Reproductive Age

Hiroaki Niitsu; Hiroaki Tsumura; Tetsuya Kanehiro; Hiroaki Yamaoka; Hiroyuki Taogoshi; Naoki Murao

Aim: To study the characteristics and surgical treatment of inguinal endometriosis (IEM), which can occur in women of reproductive age. Methods: Patients who underwent groin surgery at the Hiroshima City Funairi Citizens Hospital between 2004 and 2017 were retrospectively examined. Patients with IEM were divided into 3 groups based on the site of occurrence as follows: at a hernia sac or hydrocele of Nuck’s canal (type I), round ligament (type II), or subcutaneous area (type III). Clinical characteristics were compared among groups. Results: Of 2,798 patients investigated, 28 were pathologically diagnosed as having IEM with 15, 10, and 3 classified as type I, II, and III respectively. All patients presented with a mass (median 20 mm) and/or bulge that mainly occurred at the right inguinal region. Sixteen patients presented with inguinal pain associated with menstruation. While the groups did not differ in terms of most clinical characteristics, the lack of a preoperative diagnosis of IEM occurred more frequently for type I than for types II and III. Conclusions: Because IEM-type I might be underdiagnosed preoperatively, complete resection of a hernia sac or hydrocele of Nuck’s canal with subsequent pathological examination is required for women of reproductive age with an inguinal disease.

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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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