Publications by authors named "Ohnuma N"

Toxoplasma gondii is a common perorally transmitted parasite; however, its immunopathogenesis in gut-associated tissues remains unclear. Here, we compared disease manifestation in C57BL/6 immunocompetent wild type (WT) mice and immunocompromised interferon (IFN)-γ-deficient (GKO) mice after peroral infection (PI) with T. gondii cysts (Fukaya strain).

View Article and Find Full Text PDF

Purpose: With current treatment regimens, high-risk neuroblastoma (NB) remains largely incurable. Oncolytic viral therapy uses replication-competent viruses, like Sindbis virus (SINV), to kill cancers. The SINV AR339 strain is blood borne and relatively non-virulent.

View Article and Find Full Text PDF

Ghrelin consists of 28 amino acid residues with an octanoyl modification at the third serine residue. Recently we have found that the C-terminal part of ghrelin protects the ester bond of 3-octanoyled serine from plasma esterases and plays the essential role to prolong the plasma half-life and to show its biological activity in vivo. In the present study, we researched whether the C-terminal part of ghrelin has a potential to prolong the plasma half-life of motilin, by comparing the pharmacokinetics of various chimeric peptides of ghrelin and motilin.

View Article and Find Full Text PDF

Background: In the recent years, surgical resection with pre- and/or postoperative chemotherapy has markedly improved the survival rate of hepatoblastoma patients. We herein report the results of patients treated with the current protocol of the Japanese Study Group for Pediatric Liver Tumor, JPLT-2.

Methods: A total of 279 patients with malignant liver tumor were enrolled in JPLT-2.

View Article and Find Full Text PDF

Ticks are ectoparasitic arthropods that can transmit a variety of microorganisms to humans and animals during blood feeding, causing serious infectious disorders, including Lyme disease. Acaricides are pharmacologic agents that kill ticks. The emergence of acaricide-resistant ticks calls for alternative control strategies for ticks and tick-borne diseases.

View Article and Find Full Text PDF

A 59-year-old woman with a history of lung sarcoidosis developed general edema and exertional dyspnea. An electrocardiogram showed first-degree atrioventricular block with complete right bundle branch block. Chest X-ray showed cardiomegaly.

View Article and Find Full Text PDF

We previously found that Plk1 inhibited the p53/p73 activity through its direct phosphorylation. In this study, we investigated the functional role of Plk1 in modulating the p53 family member TAp63, resulting in the control of apoptotic cell death in liver tumor cells. Immunoprecipitation and in vitro pull-down assay showed that p63 binds to the kinase domain of Plk1 through its DNA-binding region.

View Article and Find Full Text PDF

Despite the progress of therapy, outcomes of advanced hepatoblastoma patients who are refractory to standard preoperative chemotherapy remain unsatisfactory. To improve the mortality rate, novel prognostic markers are needed for better therapy planning. We examined the methylation status of 13 candidate tumor suppressor genes in 20 hepatoblastoma tumors by conventional methylation-specific PCR (MSP) and found hypermethylation in 3 of the 13 genes.

View Article and Find Full Text PDF

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).

View Article and Find Full Text PDF

Hepatoblastoma is one of the common pediatric solid tumors with frequent mutation of the beta-catenin gene which might be an early event of its carcinogenesis. However, the detailed molecular mechanism is still unknown. We studied the expression levels of CCAAT/enhancer binding protein alpha (C/EBPalpha) and C/EBPbeta, which regulate differentiation and growth of embryonic hepatocytes, to establish whether or not they were involved in affecting the clinical behavior of hepatoblastoma.

View Article and Find Full Text PDF

Background/purpose: There are various treatment strategies for gastroesophageal varices in children. We studied the therapeutic value of endoscopic variceal clipping (EVC) and ligation (EVL).

Methods: Four hundred ninety-nine endoscopic examinations performed between 1991 and 2005 were retrospectively analyzed.

View Article and Find Full Text PDF

Purpose: The aim of this study was to understand the level of bile flow by perinatal transitions of the hepatobiliary cyst size in biliary cystic malformation (BCM) cases and to examine the association between the transitions of the cyst size, cholangiographic images of the intrahepatic bile ducts (IHBDs), and histological features of the liver specimens in BCM.

Methods: We measured perinatal size of the hepatobiliary cyst in 7 BCM cases, composed of 1 case with choledochal cyst and 6 cases with biliary atresia (BA). Bile excretion was inferred from the transition of cyst size and the postoperative course.

View Article and Find Full Text PDF

Background: Pancreaticobiliary maljunction (PBM), which frequently accompanies choledochal dilation, is a high risk factor for biliary tract (gallbladder, bile duct) carcinoma because of the continuous reflux of pancreatic juice into the biliary tract. The aim of this study was to clarify the preferable operative age in PBM patients for the prevention of biliary tract carcinogenesis, with reference to the dilation types of bile ducts.

Methods: There were 165 PBM patients in total studied, including 92 pediatric patients (< or =15 y) (cystic, 63; spindle-like, 29; nondilation, 0) and 73 adult patients (>15 y) (cystic, 45; spindle-like, 18; nondilation, 10) who underwent operative excision of extrahepatic bile ducts or cholecystectomy.

View Article and Find Full Text PDF

The prognosis for children with malignant solid tumors has improved dramatically in Japan. During the last two decades, various groups have conducted sequential studies of the treatment of children with neuroblastoma, Wilms' tumor, and hepatoblastoma. Most institutes participated in nonrandomized trials designed to evaluate the safety and efficacy of combination chemotherapy, surgery, and radiotherapy in each group study and treated children with these tumors The results are reviewed and areas for future investigation are identified.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

Purpose: Members of the Japanese Biliary Atresia Society were surveyed to determine their current practice regarding early use of corticosteroids after Kasai's operation.

Methods: Questions included the patient's background data, dosage, timing, complications, and outcome. Anicteric survival with the native liver was statistically compared between groups categorized by steroid dosage using Kaplan-Meier analysis.

View Article and Find Full Text PDF

Background/aims: Hypoxia/reoxygenation (H/R) causes oxidative stress to the cell and induces apoptotic cell death. Signal transducer and activator of transcription-3 (Stat3) is one of the most important molecules involved in the initiation of liver development and regeneration, and has recently been shown to protect cells against various pathogens. In order to investigate the hepatoprotective effects of Stat3, we examined whether it protects against H/R-induced injury in primary hepatocytes.

View Article and Find Full Text PDF

We hypothesized that hyperbaric oxygenation (HBO) combined with a long tube (LT) [HBO + LT] would be more effective than HBO combined with a short tube (ST) [HBO + ST] for simple adhesive postoperative intestinal obstruction (APIO) in children, assuming that there is synergism between HBO and LT. The objective of this study was to determine retrospectively the effect of HBO + LT compared to HBO + ST for simple APIO in children. Seventy-three patients were diagnosed with simple APIO, and 51 of these patients were treated with HBO + LT during 104 HBO sessions, while 22 were treated with HBO + ST during 34 HBO sessions.

View Article and Find Full Text PDF

Telomerase, an enzyme related with cellular immortality, has been extensively studied in many kinds of malignant tumours for clinical diagnostic or prognostic utilities. Telomerase activity is mainly regulated by the expression of hTERT (human telomerase reverse transcriptase), which is a catalytic component of human telomerase. To evaluate whether the levels of hTERT mRNA provides a molecular marker of hepatoblastoma malignancy, we examined hTERT mRNA expression levels in the primary hepatoblastoma tissues by fluorescent RT-PCR using LightCycler technology and followed up the clinical outcomes in 63 patients listed in the Japanese Study Group of Pediatric Liver Tumor between 1991 and 2002.

View Article and Find Full Text PDF

Hepatoblastoma is one of the most common malignant liver tumors in young children. Recent evidences have suggested that the abnormalities in Wnt signaling pathway, as seen in frequent mutation of the beta-catenin gene, may play a role in the genesis of hepatoblastoma. However, the precise mechanism to cause the tumor has been elusive.

View Article and Find Full Text PDF

STAT1 (signal transducer and activator of transcription 1) is potentially involved in cell survival, as well as cell death, in different types of cells. The present study was designed to examine the effects of STAT1 on hypoxia/re-oxygenation (H/R)-induced cell death and/or survival, and the underlying mechanisms of any such effects. H/R was shown to induce apoptotic cell death of rat hepatocytes.

View Article and Find Full Text PDF

Purpose: To investigate the optimal strategy of preoperative transcatheter arterial chemoembolization (TACE) for hepatoblastoma.

Methods: Between 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.

View Article and Find Full Text PDF

Background/aims: To clarify the association between the reovirus infection of the hepatobiliary tree and the development of infantile obstructive cholangiopathy (IOC) including biliary atresia (BA) and congenital dilatation of the bile duct (CBD).

Methods: We designed reovirus common primers for nested RT-PCR based on the L3 gene segment. The spectrum and the sensitivity of common primers were evaluated with purified reoviral RNAs and reovirus mixed with stool samples.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

Multilocular cyst of the kidney is an uncommon benign renal neoplasm. Because of its benign nature, this lesion is best managed by nephron-sparing surgery. This report describes a child who underwent a partial nephrectomy for a multilocular cyst of the kidney.

View Article and Find Full Text PDF