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Dive into the research topics where Katsunori Kouchi is active.

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Featured researches published by Katsunori Kouchi.


Journal of Pediatric Surgery | 1999

Nonoperative management of blunt pancreatic injury in childhood

Katsunori Kouchi; Masahiro Tanabe; Hideo Yoshida; Jun Iwai; Tadashi Matsunaga; Yasuhiro Ohtsuka; Hiroaki Kuroda; Tomoro Hishiki; Naomi Ohnuma

PURPOSE Nonoperative management for blunt pancreatic injury in children was performed between 1977 and 1998. The efficiency and safety of nonoperative management was examined. METHODS Pancreatic injury was diagnosed in 20 children. The surgical indication was determined by hemodynamic instability and the management of associated injuries. Children without surgical indications were treated initially by nonoperative management. RESULTS Nineteen of 20 children were treated initially nonoperatively, and 18 of the 19 survived. Surgical exploration was performed in only 1 child with perforation of the duodenum and bile duct. One child died of complications of total parenteral nutrition. Ultrasound scan and computed tomography scan showed pancreatic contusion in 9, laceration in 6, and injury of the main pancreatic duct (MPD) in 5. Pseudocysts were detected in 10 (5 laceration and 5 MPD injury). Pseudocysts smaller than 10 cm disappeared after nonoperative management, and those larger than 10 cm required operative management. Rupture of pseudocysts occurred in 2 children by rotating the upper torso. CONCLUSIONS Nonoperative management of pancreatic injuries is effective in children, although careful management is required to avoid complications. Pseudocysts smaller than 10 cm were treated successfully by nonoperative management, and those larger than 10 cm required surgical management.


Surgery Today | 2004

Optimal strategy of preoperative transcatheter arterial chemoembolization for hepatoblastoma.

Yasuhiro Ohtsuka; Tadashi Matsunaga; Hideo Yoshida; Katsunori Kouchi; Tadao Okada; Naomi Ohnuma

PurposeTo investigate the optimal strategy of preoperative transcatheter arterial chemoembolization (TACE) for hepatoblastoma.MethodsBetween 1992 and 2001, 7 children with hepatoblastoma (aged 9 months to 13 years) underwent preoperative TACE. The chemoembolic agent used was an emulsion of pirarubicin and lipiodol. Four patients without distant metastasis underwent “primary” TACE without systemic chemotherapy. The other 3 with distant metastases underwent “delayed” TACE following systemic chemotherapy. These patients were all examined retrospectively using clinical data.ResultsThe average dosage of lipiodol was 0.6 ml per tumor maximal diameter (cm). All the primary cases showed a significant decrease in α-fetoprotein (AFP) and a reduction in the tumor size. They consequently underwent a complete surgical resection and are now disease free. All the delayed cases showed a slight decrease in AFP and underwent complete surgical resection; however, two of them died of lung metastases, and the other died of a second malignancy. Regarding complications, liver dysfunction and pulmonary embolism occurred in one patient each.ConclusionsFor patients without distant metastasis, regardless of the resectability of the primary tumor, TACE may be considered the initial and only preoperative treatment, and it may be repeated. For patients with distant metastases, their complete eradication with systemic chemotherapy prior to TACE is essential.


Journal of Pediatric Gastroenterology and Nutrition | 2014

Role of pediatric endoscopic retrograde cholangiopancreatography in an era stressing less-invasive imaging modalities.

Takeshi Saito; Keita Terui; Tetsuya Mitsunaga; Mitsuyuki Nakata; Yutaka Kuriyama; Yasuyuki Higashimoto; Katsunori Kouchi; Naomi Onuma; Hideo Takahashi; Hideo Yoshida

Background:The significance of pediatric endoscopic retrograde cholangiopancreatography (ERCP) according to age or disease variation is inconclusive. This study aimed to evaluate the usefulness of pediatric ERCP in diagnosing or treating small children with pancreaticobiliary disorders, including choledochal cyst (CC) and biliary atresia (BA). Methods:From 1980 to 2011, 235 ERCPs were performed in 220 pediatric patients (median age, 2 years) at our institution. Underlying pathology was CC in 92 patients (3 years), BA in 62 patients (55 days), and others in 66 patients. Success and complication rates, and ERCP findings were retrospectively analyzed. Results:The overall success rate was 96%. Rates for individual pathologies were 99% for CC, 92% for BA, and 96% for others. The success rate was 100% among children >3 years, but 92% when limited to infants. Post-ERCP hyperamylasemia and duodenal perforation occurred in 9% and 0.4% of cases, respectively. Regarding preoperative evaluation of the pancreaticobiliary system in CC, ERCP clearly delineated pancreaticobiliary maljunction (79%) and the pancreatic duct (94%), whereas it visualized the common bile duct and intrahepatic bile duct at relatively low rates (77% and 33%, respectively). ERCP successfully identified 16 cases (18%) with non-BA of 90 patients with suspected BA. Moreover, ERCP demonstrated only pancreatic duct in 70% of all BA. Conclusions:ERCP among children including infants with CC and BA can be performed with fairly satisfactory results. Although pediatric ERCP can also help describe the pancreaticobiliary system in detail, its indication should be deliberately considered when anatomical information from less-invasive imaging modalities is insufficient.


Clinical Cancer Research | 2005

Shc Family Expression in Neuroblastoma: High Expression of shcC Is Associated with a Poor Prognosis in Advanced Neuroblastoma

Elena Terui; Tadashi Matsunaga; Hideo Yoshida; Katsunori Kouchi; Hiroaki Kuroda; Tomoro Hishiki; Takeshi Saito; Shin-ichi Yamada; Hiroshi Shirasawa; Naomi Ohnuma

The biological features and prognosis of neuroblastoma, a neural crest-derived pediatric tumor, are closely associated with expression of the Trk receptor. Because the Shc family proteins (ShcA, ShcB, and ShcC) are adaptors for various receptors, including Trk receptors, and are regulators of neuronal cell development, we speculated that they may play a role in neuroblastoma. Therefore, in this study, we used semiquantitative reverse transcription-PCR to examine the expression of these three genes in 15 neuroblastoma cell lines, an all-trans-retinoic acid–treated neuroblastoma cell line, and 52 tumor samples. In neuroblastoma cell lines and tumor samples, shcA was ubiquitously and highly expressed. Little expression of shcA was observed. Also, shcB was hardly expressed in neuroblastoma cell lines, but its expression in RT-BM-1 cells was enhanced after all-trans-retinoic acid–induced differentiation, and it was highly expressed in low-stage tumors (P = 0.0095). This suggests that ShcB participates in cellular differentiation and may correlate with a favorable prognosis in neuroblastoma. Finally, the expression of shcC was observed in most of the neuroblastoma cell lines and in some stage 4 patients. Patients with a high expression of shcC had a very poor prognosis (P < 0.0001) and amplification of MYCN, and all died within 31 months after diagnosis. Therefore, ShcC seems to be associated with an aggressive tumor phenotype, perhaps by enhancing TrkB signals. Our results suggest that the expressions of shcB and shcC are important biological factors in neuroblastoma and are useful prognostic indicators.


Journal of Pediatric Surgery | 2008

Endoscopic sphincterotomy is a useful preoperative management for refractory pancreatitis associated with pancreaticobiliary maljunction.

Keita Terui; Hideo Yoshida; Katsunori Kouchi; Tomoro Hishiki; Takeshi Saito; Tetsuya Mitsunaga; Ayako Takenouchi; Toshio Tsuyuguchi; Taketo Yamaguchi; Naomi Ohnuma

BACKGROUND Pancreatitis associated with pancreaticobiliary maljunction (PBM) is commonly treated nonoperatively before surgery. It is, however, sometimes uncontrollable, and little has been reported about the management. METHODS Focusing on the preoperative management, we reviewed clinical courses of 4 PBM cases (ages 1 to 7 years old). Each had pancreatitis that was totally resistant to medical treatment and was applied endoscopic sphincterotomy (ES). RESULTS The first case underwent percutaneous transhepatic catheter drainage (PTCD) primarily. In spite of daily lavage using the drainage tube for a week, plugs located in the common channel were not removed, and clinical findings were not improved. Therefore, ES followed by removal of protein plugs was performed to improve pancreatitis dramatically. Through this experience, 3 subsequent cases with refractory pancreatitis all underwent successful ES primarily soon after the medical treatments turned out to be ineffective. In all 4 cases, protein plugs were impacted in common channels, and ES could successfully remove the plugs that were impossible to remove by using PTCD. Improved preoperative pancreaticobiliary decompression by ES shortens the duration of recalcitrant acute pancreatitis associated with PBM allowing for a subsequent safe operation. CONCLUSIONS Endoscopic sphincterotomy is one of the useful preoperative managements for refractory pancreatitis associated with PBM.


Pediatric Radiology | 2000

Intralobar bronchopulmonary sequestration evaluated by contrast-enhanced three-dimensional MR angiography.

Katsunori Kouchi; Hideo Yoshida; Tadashi Matsunaga; Yasuhiro Ohtsuka; Hiroaki Kuroda; Tomoro Hishiki; Yoshiharu Satou; Keita Terui; Tetsuya Mitsunaga; Naomi Ohnuma

Abstract Bronchopulmonary sequestration (PS) is characterized by non-functioning lung tissue fed from one or several aberrant systemic arteries. The condition is diagnosed by visualizing the feeding arteries using non-invasive CT, MRI, colour Doppler sonography or conventional angiography. We present a 5-year-old boy in whom intralobar sequestration was diagnosed using contrast-enhanced 3D MR angiography, which visualised fine blood vessels in the thoraco-abdominal region without arterial puncture. This technique is useful for diagnosing PS.


American Journal of Medical Genetics Part A | 2003

Gorlin syndrome with ulcerative colitis in a Japanese girl

Katsunori Fujii; Toshiyuki Miyashita; Taku Omata; Kazuhiko Kobayashi; Jun-ichi Takanashi; Katsunori Kouchi; Masao Yamada; Yoichi Kohno

We present the case of a 14‐year‐old Japanese girl who had both Gorlin syndrome and ulcerative colitis. She had complained of blood stools for 6 months and severe scoliosis from her infancy. Physical examination revealed multiple nevi, palmar and plantar pits, jaw cysts, and calcification of the falx cerebri, leading to the diagnosis of Gorlin syndrome. Total colonoscopy revealed an edematous and spotty bleeding mucosa extending from the anus to the transverse colon. Histological examination was also compatible with ulcerative colitis. Thus, we diagnosed her as having Gorlin syndrome with ulcerative colitis. Gene analysis revealed a mutation, 1247InsT, in the human patched gene (PTCH), resulting in the truncation of PTCH protein. Since Gorlin syndrome and ulcerative colitis are rare disorders in childhood, this association is interesting, suggesting a correlation between the hedgehog signaling and intestinal disorders.


Journal of Muscle Research and Cell Motility | 1993

Incorporation of microinjected biotin-labelled actin into nascent myofibrils of cardiac myocytes: an immunoelectron microscopic study

Katsunori Kouchi; Hideyo Takahashi; Yutaka Shimada

SummaryIncorporation of microinjected biotin-labelled actin into nascent myofibrils of cultured cardiac muscle cells was investigated by immunogold electron microscopy. At the proximal parts of myofibrils, gold labelling was first found (at about 4 min after injection) around the A-band level. This observation suggests that polymerization of actin or the addition of newly-formed actin filaments occurs preferentially in association with myosin filaments to increase the myofibrillar girth. The distal terminals of developing myofibrils were also labelled at about 4 min after injection. This rapid incorporation of actin subunits at the myofibrillar ends suggests the continued reorganization and/or de novo formation of myofibrils at these positions. Along the extending direction of the myofibrillar terminals, gold particles were arranged in rows on the inner surface of the sarcolemma. These rows of particles continued to become longer with incubation. It appears that actin subunits are added at the membrane-associated ends of pre-existing actin filaments to increase the length of myofibrils.


Gastrointestinal Endoscopy | 2004

Efficacy of ERCP via the accessory papilla in children with choledochal cysts.

Katsunori Kouchi; Hideo Yoshida; Tadashi Matsunaga; Hiroaki Kuroda; Tomoro Hishiki; Takeshi Saito; Gen Matsuura; Shugo Komatsu; Naomi Ohnuma

BACKGROUND ERCP via the major duodenal papilla in children with choledochal cyst may not clearly visualize the entire pancreatic duct and the junction of the pancreatic and biliary ducts. This may be caused by obstruction of the pancreatic duct by a dilated common bile duct. METHODS Patients with choledochal cysts who underwent ERCP with injection of contrast medium at the major duodenal papilla were classified as either belonging to a MP group, in which the entire pancreatic duct and junction of the pancreatic and biliary ducts were visualized, or to a M/AP group, in which these structures were either partially visualized or not visualized. ERCP via the accessory papilla subsequently was performed in the M/AP group by using 0.6- or 0.8-mm metal-tip catheters. The efficacy of ERCP via the accessory papilla in children with choledochal cysts was evaluated. OBSERVATIONS ERCP was performed in 13 patients. Seven were assigned to the MP group and 6 to the M/AP group. ERCP via the accessory papilla in the M/AP group was successful in 5 of the 6 patients; pancreas divisum was demonstrated in one, a protein plug at the main pancreatic duct in another, and the entire pancreatic duct and junction of the pancreatic and biliary ducts in the remaining 3 patients. No patient developed pancreatitis as a result of ERCP, including ERCP via the accessory papilla. CONCLUSIONS In children with choledochal cyst, ERCP via the accessory papilla is an effective method for visualization of the detailed structure of the entire pancreatic ductal system and junction of the pancreatic and biliary ducts when ERCP via the major duodenal papilla is unsuccessful.


Pediatric Surgery International | 2018

Neonates undergoing gastrointestinal surgery have a higher incidence of non-IgE-mediated gastrointestinal food allergies

Takahiro Korai; Katsunori Kouchi; Ayako Takenouchi; Aki Matsuoka; Kiyoaki Yabe; Chikako Nakata

PurposeWe aimed at investigating the incidence and risk factors of non-IgE-mediated gastrointestinal food allergies (non-IgE-GI-FAs) in neonates and infants.MethodsA total of 126 infants who underwent neonatal gastrointestinal surgeries were grouped into those with (n = 13) and those without an onset of non-IgE-GI-FAs (n = 113). The characteristics of the two groups (e.g., birth weight, delivery type, small intestinal surgeries, and pre-/postoperative nutrition) were compared. Small intestinal surgeries were classified into those with and those without full-layer invasion of the small intestine. For the statistical analysis, postoperative nutrition was classified into breast milk only, formula milk, and elemental diet only.ResultsExcept for full-layer surgical invasion of the small intestine and the period of parenteral nutrition, no significant differences were found between the two groups. Surgery with full-layer invasion was a risk factor of non-IgE-GI-FAs (odds ratio (OR) 10.70, 95% confidence interval (95% CI) 2.11–54.20; p = 0.004). Formula milk after surgery was a risk factor of non-IgE-GI-FAs when compared to breast milk (OR 5.65, 95% CI 1.33–24.00; p = 0.019).ConclusionNeonates undergoing gastrointestinal surgery have a higher incidence of non-IgE mediated gastrointestinal food allergies. We recommend that formula milk should not be administered to newborns who underwent neonatal gastrointestinal surgeries with full-layer invasion of the small intestine.

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Hideo Yoshida

Boston Children's Hospital

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Naomi Ohnuma

University of Texas Southwestern Medical Center

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Takeshi Saito

Jichi Medical University

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