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Featured researches published by Yoshihisa Sera.


Journal of Pediatric Surgery | 1996

Laparoscopic surgery for neuroblastoma identified by mass screening

Hirotoshi Yamamoto; Mitsuhiro Yoshida; Yoshihisa Sera

Most neuroblastoma identified by mass screening are clearly different from the clinically diagnosed tumors with respect to biology, epidemiology, and outcome. Because the neuroblastomas detected by mass screening have favorable biological features (97% survival rate at 5 years), aggressive surgery may not be appropriate for such tumors. Laparoscopic adrenalectomy was performed on a 9-month-old boy and two 8-month-old girls who had suitable lesions. The tumors were small (< 20 mm in diameter). With the patients under general anesthesia, five trocars were placed in the abdomen. The abdominal wall traction method was used in addition to pneumoperitoneum. Intraabdominal pressure was maintained at below 4 mm Hg. The adrenal tumors were well encapsulated and completely excised, placed into a plastic bag, and removed through one of the 10-mm trocar sites. No lymphadenopathy was observed. The postoperative course was uneventful. The tumors were of favorable Shimada histology and had no N-myc gene amplification. The patients have survived, with no evidence of recurrence or metastasis, through the follow-up period of 17 to 22 months.


Medical and Pediatric Oncology | 1998

Stratification of treatment of stage 4 neuroblastoma patients based on N-myc amplification status

Michio Kaneko; Hirokazu Nishihira; Hideo Mugishima; Naomi Ohnuma; Koonosuke Nakada; Keisei Kawa; Masahiro Fukuzawa; Sachiyo Suita; Yoshihisa Sera; Yoshiaki Tsuchida

BACKGROUND It has been shown that children aged more than 12 months with stage 3 and 4 neuroblastoma with N-myc amplification do worse than those without amplification. Development of an innovative chemotherapeutic protocol for patients in such an extremely poor-risk group was the purpose of this study. PROCEDURE Since March 1991 a new protocol for the treatment of advanced neuroblastoma was started. When N-myc was amplified more than 10-fold, patients received regimen A3, in which cyclophosphamide 1,200 mg/m2 was given on days 1 and 2; hence the dose of cytotoxic drugs was doubled. Patients with fewer than 10 copies of N-myc received regimen new A1, which is very similar to regimen A1 that had been used until March 1991 for all patients with advanced neuroblastoma with/without N-myc amplification. The efficacy of regimen A3 was evaluated. RESULTS The relapse-free survival rate at 1 and 2 years for stage 4 patients older than 12 months of age with N-myc amplification of more than 10-fold was 43% and 29%, respectively, with regimen A1 and that for the same subgroup of patients treated with regimen A3 since March 1991 was 79% and 49%, respectively; the difference is statistically significant. On the other hand, there were no differences in the relapse-free survival rate at 1 year and 2 years for stage 4 patients with fewer than 10 copies of N-myc between those treated with regimen A1 and those treated with new A1 since March 1991. CONCLUSIONS Stratification based on N-myc amplification into new A1 and A3 treatment protocols is of significant clinical importance. Regimen A3 was well tolerated and showed an improvement in clinical results in stage 4 patients with N-myc amplified more than 10-fold.


Transplantation | 2000

Manganese deposition in the globus pallidus in patients with biliary atresia.

Shinji Ikeda; Yasuo Yamaguchi; Yoshihisa Sera; Hajime Ohshiro; Shinichiro Uchino; Yasuyuki Yamashita; Michio Ogawa

BACKGROUND Chronic liver diseases may alter trace element contents in the brain. Among these trace elements, manganese is a ubiquitous transition metal excreted by the liver into the bile. Blood concentrations of manganese are elevated in patients with biliary atresia who have undergone hepatic portoenterostomy. The present study investigated the effects of liver transplantation on manganese deposition in the brain in such patients. METHODS The signal intensity of the globus pallidus was calculated as an index defined as the percentile ratio of signal intensity in the globus pallidus to the subcortical frontal white-matter in sagittal T1-weighted magnetic resonance imaging planes. RESULTS Brain magnetic resonance imaging revealed hyperintense signals in the globus pallidus due to manganese deposition in biliary atresia patients. Few neurologic symptoms related to manganese intoxication were observed. However, one 23-year-old female with biliary atresia had depressive symptoms and dyskinesia; she improved after oral administration of the dopamine precursor, L-DOPA. Manganese deposition disappeared in two patients after living-related reduced-size hepatic transplantation. CONCLUSIONS Manganese accumulates in the brain during cholestasis associated with biliary atresia and disappears after hepatic transplantation. Manganese deposition is likely to be subclinical and reversible but may be associated with some age-related neurologic symptoms.


Journal of Pediatric Surgery | 1999

Surgical indications for patients with hyperammonemia.

Shinji Ikeda; Yoshihisa Sera; Hajime Ohshiro; Shinichiro Uchino; Takako Uchino; Fumio Endo

BACKGROUND/PURPOSE The authors surgically treated seven of eight patients with congenital portosystemic shunt and hyperammonemia. This entity is uncommon in children. METHODS The patients included five boys and three girls with a mean age of 8 years (range, 7 months to 24 years). Preoperative symptoms included hyperammonemia. Hepatic encephalopathy was evident in five patients. Diagnosis and assessment were made by ultrasound scan, magnetic resonance imaging (MRI), angiography, and 123 I-iodoamphetamine per-rectal portal scintigraphy. Surgical banding was done for five patients and transvenous coil embolization for two. One patient was not a surgical candidate because there were no intrahepatic portal veins. RESULTS In four of the five patients treated using surgical banding, and in both patients who underwent coil embolizations, hyperammonemia and clinical symptoms improved soon after surgery. However, in the remaining patient, hyperammonemia worsened after surgery, and reoperation was needed because of a severe portal hypertension, possibly caused by malconformation of hepatic veins. CONCLUSIONS For patients with congenital portosystemic shunt, early diagnosis and surgery are needed to prevent damage to central nerves caused by persistent hyperammonemia. Maldevelopment of the intrahepatic portal veins is a surgical option, if the patient has a normal liver architecture, but malconformation of hepatic veins or severe anomalies such as cardiac defects would rule out surgical intervention.


European Journal of Pediatrics | 1989

Serial ultrasonic examination to differentiate biliary atresia from neonatal hepatitis--special reference to changes in size of the gallbladder.

S. Ikeda; Yoshihisa Sera; M. Akagi

We performed serial ultrasonic examinations to differentiate biliary atresia from neonatal hepatitis. The subjects studied were 144 children (100 normal neonates and infants, 31 patients with neonatal hepatitis and 13 patients with biliary atresia). They were examined by ultrasound before, during and after feeding. In 97 out of 100 normal children and all patients with neonatal hepatitis, the gallbladder was identified, and the change in size following oral feeding was observed. In four children with severe neonatal hepatitis which could not be differentiated from biliary atresia by clinical and laboratory data, we readily identified the gallbladder and observed the change in the size following oral feeding. In 8 of 13 patients with biliary atresia, we identified a small gallbladder whose size was not affected by oral feeding. In the other patients the gallbladder was not identified before, during or after oral feeding. On the basis of these results, we consider that serial ultrasonic examination with oral feeding aids in a differential diagnosis of biliary atresia and neonatal hepatits.


Digestive Diseases and Sciences | 1999

Surgical Correction of Patent Ductus Venosus in Three BroThers

Shinji Ikeda; Yasuo Yamaguchi; Yoshihisa Sera; Hajime Ohshiro; Shinichiro Uchino; Michio Ogawa

We report the presence of a patent ductusvenosus in three broThers who underwent surgicalcorrection. Patent ductus venosus was demonstrated byultrasonography. Portosystemic venous shunt ratios asevaluated by [123I]iodoamphetamine per rectalportal scintigraphy were 67%, 50%, and 77%,respectively. Histologic examination of liver biopsyspecimens revealed fatty degeneration in all cases.Portal vein pressure before and after temporarily occluding thepatent ductus venosus was estimated by an Anthron P-Ucatheter introduced into the portal vein via theligament teres hepatis. Portal venous pressure increased from 10 to 17 cm H2O, 16 to 23 cmH2O, and 14 to 27 cm H2O,respectively. The refore, banding of the ductus venosuswith Teflon tape was attempted to prevent portalhypertension following complete ligation. As a result, portal venous pressures afterstricture of the ductus venosus were 12, 21, and 20 cmH2), respectively. Bile acid and liver enzymes decreasedand returned to normal within 14 days after surgery. Interestingly, serum concentrations ofhepatocyte growth factor (HGF) increased significantlyafter restoration of the portal blood flow and thengradually decreased, but remained persistently elevated for at least two weeks in two cases measuredafter surgical correction. One month after correction,liver function returned to normal as assessed byserological and histological parameters in all cases. These results suggest that it is important todetermine wheThe r stricture or complete ligation isindicated for a patent ductus venosus during surgicalcorrection, based on the portal venous pressure after temporal test occlusion of the duct. Inaddition, HGF may be a useful marker for normalizationof hepatic microcirculation after surgery.


Pediatric Radiology | 1998

Gallbladder contraction in biliary atresia: a pitfall of ultrasound diagnosis

Shinji Ikeda; Yoshihisa Sera; Hajime Ohshiro; Shinichiro Uchino; Miwa Akizuki; Yuichi Kondo

Abstract In 3 (9 %) of 34 children with biliary atresia, US revealed gallbladder contraction following an oral feed, given on admission, but not with subsequent feeds. Surgery revealed a Kasai type IIIa biliary atresia with a patent communication between the gallbladder and duodenum. We propose that the bile ducts may initially have been patent, but then gradually became obliterated secondary to inflammation. These cases may explain the development of one type of biliary atresia.


Journal of Pediatric Surgery | 1999

Successful coil embolization in an infant with congenital intrahepatic portosystemic shunts.

Shinji Ikeda; Yoshihisa Sera; M. Yoshida; Toshiya Izaki; Shinichiro Uchino; Fumio Endo; Masaki Ohmuraya; Toru Beppu

The authors report the case of a 7-month-old Japanese infant with congenital intrahepatic portosystemic shunts. He had hypergalactosaemia and hyperammonemia at age 1 month. The diagnosis was made by ultrasonography and angiography. Coil embolization was performed successfully, and then hyperammonemia and hypergalactosaemia improved soon after surgery.


Journal of Pediatric Surgery | 2000

Manganese deposits in patients with biliary atresia after hepatic porto-enterostomy

Shinji Ikeda; Yoshihisa Sera; Mitsuhiro Yoshida; Hajime Ohshiro; Shinichiro Uchino; Yoichiro Oka; Kwang Jong Lee; Atsushi Kotera

PURPOSE The aim of this study was to determine if there is latent manganese toxicity in patients with biliary atresia. METHODS Fifteen children with biliary atresia were examined postoperatively with regard to whole-blood manganese levels using brain magnetic resonance imaging (MRI) and I-123 iodoamphetamine (IMP) per rectal portal scintigraphy. RESULTS Nine (60%) of the 15 had high whole-blood manganese levels (mean, 4.1 microg/dL; range, 1.2 to 9.6; normal, 0.5 to 2.5), and these 9 had hyperintense globus pallidus on T1-weighted images, with no corresponding signal change in T2 sequences. I-123 IMP per rectal portal scintigraphy was done for 13 patients to evaluate portosystemic shunt flow. 12 (92%) of these patients had an increased flow. Mean shunt ratio was estimated to be 41% (range, 0.6 to 98; normal, <5%). Encephalopathy was evident in only 1 patient. CONCLUSIONS Some patients with biliary atresia in the postoperative period have manganese deposits in globus pallidus on T1-weighted images and high whole-blood manganese levels, possibly caused by increased portsystemic shunt, and a latent or subclinical encephalopathy is also present.


Pediatric Surgery International | 1999

Extrahepatic biliary atresia associated with trisomy 18.

Shinji Ikeda; Yoshihisa Sera; M. Yoshida; Hajime Ohshiro; Mikako Ueno; Toshiya Izaki; Miwa Akizuki; Rieko Hamamoto; Shinichiro Uchino

Abstract A case of extrahepatic biliary atresia (EBA) associated with trisomy 18 is presented. A 1-month-old boy was suspected to have Alagille syndrome with obstructive jaundice, a systolic heart murmur, growth retardation, and a small, pointed chin. However, surgery and chromosomal analysis revealed EBA associated with trisomy 18. Chromosomal examination must be performed in patients with jaundice and congenital anomalies. It is possible that EBA in trisomy 18 syndrome is due to a chromosomal disorder.

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