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Dive into the research topics where Kenichi Sugita is active.

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Featured researches published by Kenichi Sugita.


Journal of Clinical Oncology | 2005

No Advantage of Dexamethasone Over Prednisolone for the Outcome of Standard- and Intermediate-Risk Childhood Acute Lymphoblastic Leukemia in the Tokyo Children's Cancer Study Group L95-14 Protocol

Shunji Igarashi; Atsushi Manabe; Akira Ohara; Masaaki Kumagai; Tomohiro Saito; Yuri Okimoto; Takehiko Kamijo; Keiichi Isoyama; Michiko Kajiwara; Manabu Sotomatsu; Kenichi Sugita; Kanji Sugita; Miho Maeda; Hiromasa Yabe; Akitoshi Kinoshita; Takashi Kaneko; Yasuhide Hayashi; Kouichiro Ikuta; Ryohji Hanada; Masahiro Tsuchida

PURPOSE To evaluate whether dexamethasone (DEXA) yields a better outcome than prednisolone (PRED) in a prospective, randomized, controlled trial for the treatment of childhood acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS Two hundred thirty-one standard-risk (SR) patients and 128 intermediate-risk (IR) non-B-cell ALL patients were registered from March 1995 to March 1999. After random assignment in each group, the PRED arm patients received PRED 60 mg/m2 during induction followed by PRED 40 mg/m2 over four intensifications in the SR group and three intensifications in the IR group. DEXA arm patients received DEXA 8 mg/m2 during induction and DEXA 6 mg/m2 during the intensifications. The maintenance phase was continued until week 104. RESULTS Event-free survival rates at 8 years in the DEXA and PRED arms were 81.1% +/- 3.9% (n = 117) and 84.4% +/- 5.2% (n = 114), respectively, in the SR group (P = .217) and 84.9% +/- 4.6% (n = 62) and 80.4% +/- 5.1% (n = 66), respectively, in the IR group (P = .625). The primary reason for treatment failure was marrow relapse. Only two extramedullary relapses occurred in the DEXA arm compared with seven relapses in the PRED arm. Although complications were more prevalent in the DEXA arm than in the PRED arm, fatal toxicity was rare both groups. CONCLUSION DEXA administered at 8 mg/m2 during induction and 6 mg/m2 during intensification showed no advantage over PRED administered at 60 mg/m2 during induction and 40 mg/m2 during intensification in both the SR and IR groups.


Leukemia | 2007

Hypercalcemia in childhood acute lymphoblastic leukemia: frequent implication of parathyroid hormone-related peptide and E2A-HLF from translocation 17;19.

Takeshi Inukai; K Hirose; T Inaba; Hidemitsu Kurosawa; A Hama; H Inada; M Chin; Y Nagatoshi; Yoshitoshi Ohtsuka; M Oda; Hiroaki Goto; Mikiya Endo; A Morimoto; M Imaizumi; N Kawamura; Y Miyajima; M Ohtake; R Miyaji; M Saito; A Tawa; F Yanai; Kumiko Goi; S Nakazawa; Kenichi Sugita

Hypercalcemia is relatively rare but clinically important complication in childhood leukemic patients. To clarify the clinical characteristics, mechanisms of hypercalcemia, response to management for hypercalcemia, incidence of t(17;19) and final outcome of childhood acute lymphoblastic leukemia (ALL) accompanied by hypercalcemia, clinical data of 22 cases of childhood ALL accompanied by hypercalcemia (>12 mg/dl) reported in Japan from 1990 to 2005 were retrospectively analyzed. Eleven patients were 10 years and older. Twenty patients had low white blood cell count (<20 × 109/l), 15 showed hemoglobin⩾8 g/dl and 14 showed platelet count ⩾100 × 109/l. Parathyroid hormone-related peptide (PTHrP)-mediated hypercalcemia was confirmed in 11 of the 16 patients in whom elevated-serum level or positive immunohistochemistry of PTHrP was observed. Hypercalcemia and accompanying renal insufficiency resolved quickly, particularly in patients treated with bisphosphonate. t(17;19) or add(19)(p13) was detected in five patients among 17 patients in whom karyotypic data were available, and the presence of E2A-HLF was confirmed in these five patients. All five patients with t(17;19)-ALL relapsed very early. Excluding the t(17;19)-ALL patients, the final outcome of ALL accompanied by hypercalcemia was similar to that of all childhood ALL patients, indicating that the development of hypercalcemia itself is not a poor prognostic factor.


European Journal of Pharmacology | 1990

Endothelin: a potential modulator of cerebral vasospasm

Toshio Asano; Ichiro Ikegaki; Shin-ichi Satoh; Yoshio Suzuki; Masato Shibuya; Kenichi Sugita; Hiroyoshi Hidaka

1-(5-Isoquinolinesulfonyl)-homopiperazine, HA1077, is a calcium antagonist with anti-vasospastic properties. This compound blocks intracellular actions of calcium in a variety of experiments. In the present study, we examined the effects of HA1077 on the vascular actions of endothelin, an endothelium-derived vasoactive peptide, in dogs in vitro and in vivo. Intracisternal injections of endothelin (0.01 nmol) produced a significant vasospasm, as measured by angiography, similar to that seen in the canine hemorrhage model. Infusion of HA1077 led to a significant dilatation of the spastic basilar artery in endothelin-treated dogs. The rank order of in vitro contractile activity in canine cerebral arteries was a stable thromboxane A2 analog greater than endothelin greater than 5-hydroxytryptamine greater than prostaglandin F2 alpha greater than histamine greater than noradrenaline. HA1077 effectively antagonized the endothelin-induced contraction of canine basilar arterial strips in both calcium-containing and calcium-free medium. The present results indicate that HA1077 is an effective antagonist for endothelin in vitro and in vivo.


Leukemia | 2010

Long-term results of Tokyo Children's Cancer Study Group trials for childhood acute lymphoblastic leukemia, 1984–1999

Masahiro Tsuchida; Akira Ohara; Atsushi Manabe; Masaaki Kumagai; Hiroyuki Shimada; Akira Kikuchi; Tetsuya Mori; Masahiro Saito; M Akiyama; Takashi Fukushima; Kazutoshi Koike; M Shiobara; C Ogawa; Takashi Kanazawa; Y Noguchi; S Oota; Yuri Okimoto; Hiromasa Yabe; Michiko Kajiwara; Daisuke Tomizawa; K Ko; Kenichi Sugita; T Kaneko; Miho Maeda; Takeshi Inukai; Hiroaki Goto; Hiroyuki Takahashi; Keiichi Isoyama; Yasuhide Hayashi; R Hosoya

We report the long-term results of Tokyo Childrens Cancer Study Groups studies L84-11, L89-12, L92-13, and L95-14 for 1846 children with acute lymphoblastic leukemia, which were conducted between 1984 and 1999. The value of event-free survival (EFS)±s.e. was 67.2±2.2% at 10 years in L84-11, which was not improved in the following two studies, and eventually improved to 75.0±1.8% at 10 years in L95-14 study. The lower EFS of the L89-12 reflected a high rate of induction failure because of infection and delayed remission in very high-risk patients. The L92-13 study was characterized by short maintenance therapy; it resulted in poor EFS, particularly in the standard-risk (SR) group and boys. Females did significantly better than males in EFS in the early three studies. The gender difference was not significant in overall survival, partly because >60% of the males survived after the testicular relapse. Randomized studies in the former three protocols revealed that intermediate- or high-dose methotrexate therapy significantly reduced the testicular relapse rate. In the L95-14 study, gender difference disappeared in EFS. Contrary to the results of larger-scale studies, the randomized control study in the L95-14 reconfirmed with updated data that dexamethasone 8 mg/m2 had no advantage over prednisolone 60 mg/m2 in the SR and intermediate-risk groups. Prophylactic cranial irradiation was assigned to 100, 80, 44, and 44% of the patients in the studies, respectively. Isolated central nervous system relapse rates decreased to <2% in the last two trials. Secondary brain tumors developed in 12 patients at 8–22 years after cranial irradiation. Improvement of the remission induction rates and the complete omission of irradiation are currently main objectives in our studies.


Journal of Pediatric Hematology Oncology | 1993

High frequency of etoposide (VP-16)-related secondary leukemia in children with non-Hodgkin's lymphoma.

Kenichi Sugita; Toshiharu Furukawa; Masahiro Tsuchida; Yoji Okawa; Shinpei Nakazawa; Akatsuka J; Mutsuro Ohira; Kozo Nishimura

Patients and Methods : We report patients who were treated for non-Hodgkins lymphoma (NHL) or Ki-1 antigen-positive (Ki-1) lymphoma with a T-8801 protocol that included etoposide (VP-16) and behenoylcytosine arabinoside. Results : Secondary acute myeloid leukemia (AML) developed in 5 of 38 NHL and Ki-1 lymphoma patients, and the cumulative risk at 4 years was 18.4%. The median time from the initiation of the chemotherapy to the development of AML was 21 months (range, 13–30). Four patients had a FAB M5 morphology, and one had FAB M2. In four of five examined cases, chromosomal alterations involving the long arm of chromosome 11 were demonstrated at the time of development of AML. None of the 46 NHL patients who we treated with another protocol (B-8801), using significantly higher cumulative doses of VP-16 than in the case of the patients with T-8801 and a different schedule of VP-16 administration, developed secondary AML. Conclusions : The risk of secondary AML possibly related to the use of VP-16 given twice weekly.


Leukemia | 2000

Long-term follow-up of childhood acute lymphoblastic leukemia in Tokyo Children's Cancer Study Group 1981-1995.

Masahiro Tsuchida; Koichiro Ikuta; Ryouji Hanada; Saito T; Keiichi Isoyama; Kenichi Sugita; Toyoda Y; Atsushi Manabe; Kazutoshi Koike; Akitoshi Kinoshita; Miho Maeda; Ishimoto K; Sato T; Yuri Okimoto; Kaneko T; Michiko Kajiwara; Manabu Sotomatsu; Yasuhide Hayashi; Hiromasa Yabe; Ryota Hosoya; Yasutaka Hoshi; Ohira M; Fumio Bessho; Tsunematsu Y; Ichiro Tsukimoto; Shinpei Nakazawa

The objectives were as follows: Firstly, to estimate the overall probability of event-free survival (EFS) and isolated CNS relapse in the studies for children with acute lymphoblastic leukemia (ALL) during the 1980s and 1990s. Secondly, to report the EFS according to presenting features and lineage. Thirdly, to evaluate the treatment results re-classified by the risks of NCI criteria. Four consecutive protocol studies were performed in the Tokyo Childrens Cancer Study Group: L81–10 protocol (1981–1984, 189 patients), L84–11 (1984–1989, 484 patents), L89–12 (1989–1992, 418 patients) and L92–13 (1992–1995, 347 patients). Overall EFS at 5 years in each protocol was 56.5 ± 3.8(1 s.e.)%, 71.0 ± 2.1%, 67.8 ± 2.3%, and 63.4 ± 2.7%, respectively. The cumulative isolated CNS relapse rate at 5 years was 8.1 ± 2.1%, 3.5 ± 0.9%, 3.6 ± 1.0%, 1.0 ± 0.6. The EFS in SR/HR (standard risk/high risk) according to the NCI criteria in B-precursor ALL at 5 years was 61.9 ± 4.3%/41.4 ± 7.4% (lineage was not confirmed.), 72.5 ± 2.6%/63.4 ± 5.0%, 77.4 ± 2.7%/56.3 ± 4.7%, and 67.8 ± 3.4%/56.7 ± 5.4% in each protocol. Also EFSs according to NCI SR/HR at 5 years of T-ALL in protocols L84–11, L89–12 and L92–13 were 55.6 ± 16.6%/60.9 ± 10.1%, 72.7 ± 13.4%/51.6 ± 9.1%, and 77.1 ± 14.4%/53.6/10.1%, respectively. The truncation of maintenance therapy to 6 months resulted in a decreased EFS in L92–13, particularly due to an increase of bone marrow relapse after cessation of therapy in SR and HR. The NCI risk criteria work properly even in the patients treated by different intensities, so that it makes the comparison possible among the patients in various groups. The overall EFSs in childhood ALL improved in 1980s, but it seemed stable or decreased in 1990s. The short maintenance therapy resulted in poor outcome in SR on the L92–13 protocol. Many of these late relapsers were effectively rescued and overall survival remained at a high level. The proportion of patients who received cranial irradiation reduced without any increase of the CNS events.


Oncogene | 2003

Fusion of an AF4-related gene, LAF4, to MLL in childhood acute lymphoblastic leukemia with t (2 ; 11) (q11 ; q23)

Mitsuteru Hiwatari; Tomohiko Taki; Takeshi Taketani; Masafumi Taniwaki; Kenichi Sugita; Mayuko Okuya; Mitsuoki Eguchi; Kohmei Ida; Yasuhide Hayashi

We showed that the LAF4 gene on 2q11.2–12 was fused to the MLL gene on 11q23 in a pediatric patient with CD10 positive acute lymphoblastic leukemia (ALL) having t(2;11)(q11;q23). The LAF4 gene, which encodes a lymphoid nuclear protein of 1227 amino acids with transactivation potential, is thought to have a role in early lymphoid development. The LAF4 protein was homologous to AF4 and AF5q31 proteins that are fused to MLL in infant early pre-B ALL and the breakpoint of LAF4 was located within the region homologous to the transactivation domain of AF4 and AF5q31. Expression of the 8.5-kb LAF4 transcript was detected in the adult heart, brain, and placenta and in the fetal brain. LAF4 expression was found to be higher in ALL cell lines than in AML and Epstein–Barr virus-transformed B-lymphocyte cell lines. These findings suggest that LAF4, AF4 and AF5q31 might define a new family particularly involved in the pathogenesis of 11q23-associated ALL.


British Journal of Haematology | 2002

X-linked thrombocytopenia in a girl

Hirokazu Inoue; Hidemitsu Kurosawa; Shigeaki Nonoyama; Kohsuke Imai; Hisami Kumazaki; Takayuki Matsunaga; Yuya Sato; Kenichi Sugita; Mitsuoki Eguchi

Summary. We report X‐linked thrombocytopenia (XLT) in a 6‐year‐old girl with petechiae and thrombocytopenia from the age of 3 months. Her 2‐year‐old brother was also diagnosed with XLT. The Wiskott–Aldrich syndrome protein (WASP) gene was detected as a replacement of +5th G to Aon intron 6 using sequence analysis, and the WASP expression levels in this patient were one‐third those of a healthy control. The X‐inactivation analysis of the patients lymphocytes showed a random pattern of X‐chromosome inactivation. To our knowledge, this is the first confirmed report of XLT in a female.


Acta Haematologica | 1995

Human herpesvirus 6 infection associated with hemophagocytic syndrome.

Kenichi Sugita; Hiroyuki Kurumada; Mitsuoki Eguchi; Toshiharu Furukawa

Dr. Kenichi Sugita, The Second Department of Pediatrics, Dokkyo University School of Medicine, 880 Kitakobayashi, Mibu Tochigi, 321-02 (Japan) Table 1. Serological studies Virus-associated hemophagocytic syndrome (VAHS), first described by Risdall et al. [1], is a potentially self-limited proliferation of cytologically benign histiocytes exhibiting marked hemophagocytosis, in association with a systemic viral infection. Thus far, Epstein-Barr virus, cytomegalovirus, herpes simplex virus and adenovirus have been known as the most common causative agents [2-4]. We describe a girl who had VAHS associated with human herpesvirus 6 (HHV-6) infection. A 15-year-old girl, previously well, complained about common-cold-like symptoms, a sore throat, malaise and had otitis media in April 1993. Several days later, she was referred to our hospital because of fever and for evaluation of leukopenia. Physical examination revealed pharyngitis and slightly enlarged and tender cervical lymph nodes. An enlarged liver extending 1 cm below the right costal margin was palpated but no splenomegaly was found. The blood count revealed: Hb 13.2 g/dl, platelet count 115 × 109/1 and WBC 0.5 × 109/1 (band 14%, segmented neutrophils 35%, monocytes 6%, lymphocytes 45%). The CD4+/CD8+ ratio was 0.68. Bone marrow aspiration from the iliac crest revealed normal cellularity (total nuclear cells, 169 × 109/1) with a normal megakaryocyte count (0.09 × 109/1) and profuse macrophage infiltration (4.5 %) with evidence of hemophagocytosis. The coagulation screen was within normal limits. The serum lactate dehydrogenase (LDH) level was 1,097 WU (normal range: 185-330 WU), ferritin 0.631 g/l (normal range: 0.003-0.078 g/l) and total cholesterol and triglycerides were within the normal range. On serological examination, the titers of anti-HHV-6 IgM were 40 and 10 in the first and the second measurement, respectively and those of IgG were 10 and 10. The HHV-6 antibody was evaluated using the indirect immunofluorescence method as described previously [5]. Serum specimens that showed fluorescence at a 10-fold dilution were considered positive for HHV-6 antibody. During the clinical course, the titer of IgM decreased to less than 10 while that of IgG increased to 80 (table 1). These findings suggested that she had a recent HHV-6 infection. However, HHV-6 DNA could not be detected in the cultures of mononuclear cells (obtained on May 20, 1993) or in the serum (sample from June 12, 1993). No evidence of


Medical Molecular Morphology | 2002

Ultrastructural and cytochemical characterization of human cord blood cells

Tetsuya Mikami; Mitsuoki Eguchi; Hidemitsu Kurosawa; Yuya Sato; Kenichi Sugita; Hiroshi Suzumura; Nozomu Tadokoro; Hiroshi Watanabe; Noriyuki Inaba

 As part of a study to identify the characteristics of cord blood cells, we examined their morphological features by electron microscopy. Additionally, we cultured CD34-positive cells derived from cord blood and from bone marrow to perform morphological observations, as well as cytochemical examinations following the peroxidase reaction. Compared with normal peripheral blood cells, cord blood cells frequently showed immature morphology and a unique ultrastructure, such as nuclear pockets in neutrophils, several crystalloids in a single eosinophilic granule, and deformed nuclei in lymphoctytes. In contrast to bone marrow cells, cord blood cells yielded a large number of cells of immature myelo-monocytic lineages in cell culture, and demonstrated a weaker peroxidase reaction. We identified that cord blood cells were different from normal peripheral blood cells and bone marrow cells, confirming the functional differences that were previously assumed.

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