Yuhki Koga
Kyushu University
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Publication
Featured researches published by Yuhki Koga.
Cancer Research | 2004
Yuhki Koga; Akinobu Matsuzaki; Aiko Suminoe; Hiroyoshi Hattori; Toshiro Hara
To detect the novel genes expressed uniquely in neutrophils and elucidate their function, the gene expression pattern was compared by using cDNA microarray containing 240 cytokine genes between the neutrophils and peripheral blood mononuclear cells (PBMCs) obtained from healthy human donors. Twenty-six genes, including tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), were expressed in neutrophils at a level >10 times higher than that seen in phytohemagglutinin-stimulated PBMCs. The amounts of mRNA and protein of TRAIL were quantified by real-time reverse transcription-PCR and ELISA, respectively. TRAIL was expressed in resting neutrophils at the mRNA and protein levels, and its expression was enhanced after stimulation with IFN-γ. Neutrophils expressed TRAIL on the cell surface and released it into the culture media. The cytotoxicity of neutrophil-derived TRAIL against Jurkat cells was determined by flow cytometry using FITC-conjugated annexin V. When Jurkat cells were cultured with neutrophils in the presence of IFN-γ, the number of Jurkat cells undergoing apoptosis increased, and such increase depended on the effector:target ratio. This cytotoxicity was suppressed partially by adding anti-TRAIL antibody to the media. Neutrophils may exert their own antitumor effect by TRAIL. A microarray analysis was found to be a useful tool for detecting novel genes that are suggested to play unknown roles in the neutrophil function.
Supportive Care in Cancer | 2006
Akinobu Matsuzaki; Aiko Suminoe; Yuhki Koga; Miho Hatano; Sagano Hattori; Toshiro Hara
BackgroundPeripherally inserted central venous catheters (PICCs) have been increasingly used in pediatric patients. However, little is known about the incidence and risk of complications when using this device in children with cancer. The purposes of this study are to assess the feasibility of PICCs and to determine the risk factors for PICC-related complications in pediatric patients with various types of malignancies.Patients and methodsWe attempted to place PICCs in 53 patients with a median age of 5 years ranging from 2 months to 20 years. PICCs were used to administer fluid, parenteral nutrition, anticancer agents, antibiotics, and blood products and also for the through-line blood sampling. The duration of catheterization and the incidence of PICC-related complications requiring removal were retrospectively evaluated in association with the diagnosis, sex, age and body weight of the patients, size, insertion site and tip location of the catheters, type of treatment, and duration of leukopenia.ResultsPICCs were successfully placed in 109 of 112 attempts (97.3%) in 53 patients, and they were followed for a total of 11,797 catheter days (median placement, 87 days; range, 3 to 512 days). Fifty five PICCs (50.5%) were removed as a result of PICC-related complications with a rate of 4.66 per 1,000 catheter days. The most common reasons for catheter removal were occlusion (n=18), breakage/leakage (15), and infection (10). More than 70% of such complications occurred more than 30 days after placement. The catheter tip location in the superior vena cava or the right atrium might decrease the risk of complications. Other parameters did not influence the incidence of complications.ConclusionsPICCs were found to provide a reliable access for prolonged intravenous administration and blood sampling in children intensively treated for hematologic and solid malignancies, thus leading to a reduction of physical pain and psychological stress in such patients. However, the long-term placement of PICCs may also be related to an increased risk of complications.
Pediatric Blood & Cancer | 2005
Akinobu Matsuzaki; Aiko Suminoe; Yuhki Koga; Naoko Kinukawa; Koichi Kusuhara; Toshiro Hara
To assess the immune response to inactivated trivalent split influenza vaccine in children with cancer.
Pediatric Blood & Cancer | 2005
Yuhki Koga; Akinobu Matsuzaki; Aiko Suminoe; Hiroyoshi Hattori; Satomi Kanemitsu; Toshiro Hara
Sensitivity of leukemic blasts to glucocorticoid is one of the important prognostic factors for pediatric acute lymphoblastic leukemia (ALL). Alternative splicing of the glucocorticoid receptor (GR) gene results in several isoforms. We examined an association of the expression pattern of GR isoforms in leukemic blasts with their sensitivity to glucocorticoid in childhood ALL.
Pediatric Transplantation | 2009
Aiko Suminoe; Akinobu Matsuzaki; Hiroyoshi Hattori; Yuhki Koga; Toshiro Hara
Abstract: Immature DCs were generated from the peripheral blood monocytes from five children with refractory solid tumors (Ewing sarcoma, synovial sarcoma, neuroblastoma) using GM‐CSF and IL‐4. These DCs were then pulsed with tumor‐specific synthetic peptides or tumor lysates in the presence of the immunogenic protein KLH for 12 h. Pulsed DCs were administered subcutaneously every one or two weeks in an outpatient setting without any toxicity. In one patient with Ewing sarcoma, the residual tumor disappeared following autologous PBSCT and DC therapy, and a complete remission has been maintained for 77 months. In two patients with synovial sarcoma or with neuroblastoma, growth of the tumors was temporally suppressed for one and 10 months, respectively, followed by their exacerbation. A DTH response was detected against KLH in all five patients and against the tumor lysate in one patient. In the patients with a possible DC‐mediated anti‐tumor effect, the number of CD8+ HLA‐DR+ lymphocytes and INF‐γ+CD8+ lymphocytes increased and an elevation of the NK cell cytotoxic activity was observed during and/or after DC therapy. DC‐based immunotherapy may therefore be a feasible, well‐tolerated and promising approach in the treatment of children with refractory malignant tumors.
Pediatric Surgery International | 2015
Ryota Souzaki; Yoshiaki Kinoshita; Satoshi Ieiri; Makoto Hayashida; Yuhki Koga; Ken Shirabe; Toshiro Hara; Yoshihiko Maehara; Makoto Hashizume; Tomoaki Taguchi
The patient is a 3-year-old female diagnosed with PRETEXT IV hepatoblastoma (HB). Although the tumor was decreased after the neoadjuvant chemotherapy, HB still located at the porta hepatis. The patient underwent extended left lobectomy successfully after surgical simulation using three-dimensional (3D) printing liver model based on preoperative CT.
Pediatric Hematology and Oncology | 2008
Akinobu Matsuzaki; Aiko Suminoe; Yuhki Koga; Koichi Kusuhara; T. Hara; Reina Ogata; Tetsutaro Sata; Toshiro Hara
A 5-year-old girl with acute lymphoblastic leukemia in remission suffered from fatal visceral varicella-zoster virus (VZV) infection after the oral administration of a high-dose dexamethasone. She abruptly developed fulminant hepatitis and disseminated intravascular coagulation, and died 3 days later. VZV DNA and antigens were detected in the peripheral blood (6 × 108 copies/mL) and a postmortem liver specimen, respectively. The exposure to VZV was not confirmed and no skin lesions were observed. VZV infection should be considered in patients with unexplained liver dysfunction under severe immunosuppressive condition, even in the absence of viral exposure and skin involvement.
Journal of Pediatric Surgery | 2013
Ryota Souzaki; Satoshi Ieiri; Munenori Uemura; Kenoki Ohuchida; Morimasa Tomikawa; Yoshiaki Kinoshita; Yuhki Koga; Aiko Suminoe; Kenichi Kohashi; Yoshinao Oda; Toshiro Hara; Makoto Hashizume; Tomoaki Taguchi
PURPOSE In pediatric endoscopic surgery, a limited view and lack of tactile sensation restrict the surgeons abilities. Moreover, in pediatric oncology, it is sometimes difficult to detect and resect tumors due to the adhesion and degeneration of tumors treated with multimodality therapies. We developed an augmented reality (AR) navigation system based on preoperative CT and MRI imaging for use in endoscopic surgery for pediatric tumors. METHODS The patients preoperatively underwent either CT or MRI with body surface markers. We used an optical tracking system to register the reconstructed 3D images obtained from the CT and MRI data and body surface markers during surgery. AR visualization was superimposed with the 3D images projected onto captured live images. Six patients underwent surgery using this system. RESULTS The median age of the patients was 3.5 years. Two of the six patients underwent laparoscopic surgery, two patients underwent thoracoscopic surgery, and two patients underwent laparotomy using this system. The indications for surgery were local recurrence of a Wilms tumor in one case, metastasis of rhabdomyosarcoma in one case, undifferentiated sarcoma in one case, bronchogenic cysts in two cases, and hepatoblastoma in one case. The average tumor size was 22.0±14.2 mm. Four patients were treated with chemotherapy, three patients were treated with radiotherapy before surgery, and four patients underwent reoperation. All six tumors were detected using the AR navigation system and successfully resected without any complications. CONCLUSIONS The AR navigation system is very useful for detecting the tumor location during pediatric surgery, especially for endoscopic surgery.
Pediatric Blood & Cancer | 2009
Yuhki Koga; Akinobu Matsuzaki; Aiko Suminoe; Miho Hatano; Yusuke Saito; Yoshiaki Kinoshita; Tatsuro Tajiri; Tomoaki Taguchi; Kenichi Kohashi; Yoshinao Oda; Masazumi Tsuneyoshi; Toshiro Hara
A 5‐month‐old male with stage II malignant rhabdoid tumor of the kidney (MRTK) and a 24‐month‐old male with stage III MRTK were treated with surgical resection of tumors and chemotherapy of alternating ICE (ifosfamide, carboplatin, and etoposide) and VDC (vincristine, doxorubicin, and cyclophosphamide), followed by high‐dose chemotherapy using etoposide, carboplatin, and melphalan with autologous hematopoietic stem cell transplantation (SCT). Two patients have been alive without any evidence of disease for 30 and 37 months after diagnosis, respectively, and require no medication. Consolidation with SCT should be further studies for selected patients with high‐risk MRTK. Pediatr Blood Cancer 2009;52:888–890.
Journal of Pediatric Hematology Oncology | 2006
Yuhki Koga; Shouichi Ohga; Akihiko Nomura; Hidetoshi Takada; Toshiro Hara
Diamond-Blackfan anemia (DBA) is a rare congenital pure red cell aplasia occasionally presenting physical anomalies. Ribosomal protein S19 gene (RPS19) is one of the causative genes for DBA; however, the pathologic mechanism of erythroblastopenia and abnormal morphology has not been clarified. To assess the pathophysiology of DBA, the gene expression profile of 2 representative patients carrying no RPS19 mutations was compared with that of aplastic anemia (AA) patients, assessed by the microarray analyses. The K-mean clustering analysis revealed the significant categorization of 28 ribosomal protein (RP) genes into a small set of group (994 genes) (P=2.39E-17), all of which were expressed at lower levels in DBA than in AA patients. RPS19 was categorized into the set of low expressing genes in DBA patients. No mutations were determined in the promoter and coding sequences of top 10 RP genes expressed at the levels over 1.2 of the AA/DBA ratio, in 3 DBA patients. These results indicated that the lower expression of RP gene group, even without the mutation, was a distinctive feature of DBA from AA, although the study number was small. The reduced RP gene expression, by itself, may suggest an underlying mechanism of the constitutional anemia.