Kenji Okumura

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Petroleum contains many heterocyclic organosulfur compounds refractory to conventional hydrodesulfurization carried out with chemical catalysts. Among these, dibenzothiophene (DBT) and DBTs bearing alkyl substitutions are representative compounds. Two bacterial strains, which have been identified as Paenibacillus strains and which are capable of efficiently(More)
From an exposure of 25.5 kiloton-years of the Super-Kamiokande detector, 900 muon-like and 983 electronlike single-ring atmospheric neutrino interactions were detected with momentum pe > 100 MeV/c, pμ > 200 MeV/c, and with visible energy less than 1.33 GeV. Using a detailed Monte Carlo simulation, the ratio (μ/e)DATA/(μ/e)MC was measured to be 0.61 ±(More)
Toll-like receptors (TLRs) are mammalian homologues of the Drosophila Toll receptors and are thought to have roles in innate recognition of bacteria. We demonstrated that TLR 2, 4, 6, and 8 but not TLR5 were expressed on mouse bone marrow-derived mast cells (BMMCs). Using BMMCs from the genetically TLR4-mutated strain C3H/HeJ, we demonstrated that(More)
The membrane antigen B7/BB1 (refs 1, 2) is expressed on activated B cells, macrophages and dendritic cells, and binds to a counter-receptor, CD28, expressed on T lymphocytes and thymocytes. Interaction between CD28 and B7 results in potent costimulation of T-cell activation initiated through the CD3/T-cell receptor complex. Discrepancies between results(More)
NF-kappaB is activated by various stimuli including inflammatory cytokines and stresses. A key step in the activation of NF-kappaB is the phosphorylation of its inhibitors, IkappaBs, by an IkappaB kinase (IKK) complex. Recently, two closely related kinases, designated IKKalpha and IKKbeta, have been identified to be the components of the IKK complex that(More)
BACKGROUND In mammals, two possible clock genes (Clock, Per1) have very recently been reported. mPer1 (the first identified mouse period gene), in particular, shows a circadian expression in suprachiasmatic nuclei (SCN), the mammalian circadian centre. However, only mPer1 and Clock as clock components may not be sufficient to understand all the events in(More)
Natural killer T (NKT) cells constitute a distinct subpopulation of T cells with a unique antigen specificity, prompt effector functions, and an unusual tissue distribution. NKT cells are especially abundant in the liver, but their physiological function in this organ remains unclear. In the present study, we examined the possible contribution of NKT cells(More)
With the aim of establishing the basic knowledge and resources needed for applied genetics, we investigated the genome structure of red clover Trifolium pratense L. by a combination of cytological, genomic and genetic approaches. The deduced genome size was approximately 440 Mb, as estimated by measuring the nuclear DNA content by flow cytometry. Seven(More)
Tumor necrosis factor (TNF) receptor-associated factors (TRAFs) were identified as signal transducers for the TNF receptor superfamily. However, the exact roles of TRAF2 and TRAF5 in TNF-induced NF-kappaB activation still remain controversial. To address this issue, we generated TRAF2 and TRAF5 double knockout (DKO) mice. TNF- but not interleukin-1-induced(More)
Super-Kamiokande is the world’s largest water Cherenkov detector, with net mass 50,000 tons. During the period April, 1996 to July, 2001, Super-Kamiokande I collected 1678 live-days of data, observing neutrinos from the Sun, Present address: University of Pittsburgh, Pittsburgh, PA 15260, USA. Present address: California Institute of Technology, Pasadena,(More)