http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kurokawa, Manabu,Kim, Jiyeon,Geradts, Joseph,Matsuura, Kenkyo,Liu, Liu,Ran, Xu,Xia, Wenle,Ribar, Thomas J.,Henao, Ricardo,Dewhirst, Mark W.,Kim, Wun-Jae,Lucas, Joseph E.,Wang, Shaomeng,Spector, Neil L AAAS 2013 Science signaling Vol.6 No.274
<P><B>Breaking Down to Build Resistance</B></P><P>Chemotherapeutic resistance often arises because of the rewiring of signaling pathways in cancer cells. Kurokawa <I>et al.</I> found that the ubiquitin E3 ligase MDM2 triggered the breakdown of another ubiquitin E3 ligase, HUWE1. In breast cancer cells that died when exposed to the HER2 (human epidermal growth factor receptor 2) EGFR (epidermal growth factor receptor) tyrosine kinase inhibitor lapatinib, MDM2 was degraded, which enabled HUWE1 to trigger the degradation of a prosurvival protein and promote assembly and activation of a protein complex required for the execution of cell death. However, MDM2 degradation did not occur in lapatinib-resistant breast cancer cells, and thus, the abundance of HUWE1 was decreased, promoting cell survival. In a mouse xenograft model, an inhibitor of MDM2 reduced the growth of tumors generated from lapatinib-resistant breast cancer cells. Thus, MDM2 could be targeted to circumvent resistance to lapatinib in breast cancers.</P>
Dynamic Characteristics of DC-DC Converters Using Digital Filters
Kurokawa, Fujio,Okamatsu, Masashi,Ishibashi, Taku,Nishida, Yasuyuki The Korean Institute of Power Electronics 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.3
This paper presents the dynamic characteristics of buck and buck-boost dc-dc converters with digital filters. At first, the PID, the minimum phase FIR filter and the IIR filter controls are discussed in the buck dc-dc converter. Comparisons of the dynamic characteristics between the buck and buck-boost converters are then discussed. As a result, it is clarified that the superior dynamic characteristics are realized in the IIR filter method. In the buck converter, the undershoot is less than 2% and the transient time is less than 0.4ms. On the other hand, in the buck-boost converter, the undershoot is about 3%. However, the transient time is approximately over 4ms because the output capacitance is too large to suppress the output voltage ripple in this type of converter.
Kurokawa, Kenji,Ryu, Kyoung-Hwa,Ichikawa, Rie,Masuda, Akiko,Kim, Min-Su,Lee, Hanna,Chae, Jun-Ho,Shimizu, Takashi,Saitoh, Tatsuya,Kuwano, Koichi,Akira, Shizuo,Dohmae, Naoshi,Nakayama, Hiroshi,Lee, Bok American Society for Biochemistry and Molecular Bi 2012 The Journal of biological chemistry Vol.287 No.16
J-Groove Technique for Suppressing Various Anomalous Flow Phenomena in Turbomachines
Kurokawa, Junichi Korean Society for Fluid machinery 2011 International journal of fluid machinery and syste Vol.4 No.1
In operating a turbomachine at off-design conditions various instabilities caused by anomalous flow phenomena occur and sometimes lead to the damage of a turbomachine. In order to avoid these phenomena various devices characteristic to each phenomenon have been developed, however they make turbomachines large-sized and cause efficiency drop. The present author has developed a very simple and innovative device, termed "J-groove," of suppressing various anomalous flow phenomena commonly by controlling the angular momentum of the main flow. It has been revealed that J-groove makes an operation of a turbomachine stable in all flow range, causes little efficiency drop, and can be easily applied to an existing machine. Here is reviewed totally the results of suppressing various anomalous flow phenomena in turbomachines.
Flow Analysis in Positive Displacement Micro-Hydro Turbine and Development of Low Pulsation Turbine
Kurokawa, Junichi,Matsui, Jun,Choi, Young-Do Korean Society for Fluid machinery 2008 International journal of fluid machinery and syste Vol.1 No.1
In order to extract micro hydropower in the very low specific speed range, a Positive Displacement Turbine (PDT) was proposed and steady performance was determined experimentally. However, the suppression of large pressure pulsation is inevitable for practical application of PDT. The objective of the present study is to reveal the mechanism and the characteristics of pressure pulsation in PDT by use of CFD and to suppress the pressure pulsation. Unsteady CFD analysis has revealed that large pressure pulsation is caused by large variation of rotational speed of the following rotor, while the driving rotor, which is output rotor, keeps constant speed. Here is newly proposed a 4-lobe helical type rotor which can reduce the pressure pulsation drastically and the performance prediction of new PDT is determined.
Risk Assessment of Dioxin in Japan
Kurokawa, Yuji The Korean Society of Toxicology Korea Environment 2001 Toxicological Research Vol.17 No.-
In 1990, Tolerable Daily Intake (TDI) of 10 pg TCDD/kg/day for dioxins based on carcinogenicity and reproductive toxicity was determined by WHO/EURO, that resulted in the establishment of TDIs in other countries. In Japan, Ministry of Health and Welfare and Environment Agency, respectively established the TDI of 10 pg TCDD/kg/day and Health Risk Assessment Index of 5 pg TCDD/kg/day in 1996. Accumulation of new scientific data, especially by molecular toxicology since 1990, resulted in the reevaluation of TDI by WHO-ECEH and IPCS in May, 1998. At this meeting, it was stressed that \circled1 toxic effects of dioxin is mediated through Ah-receptor in both animals and humans, \circled2 use of ebody burdeni concept is better than the use of traditional NOAEL/UF approach, \circled3 inclusion of coplanar PCBs in the TDI by the use of new WHO-TEF. LOAELs (0.16~200 ng TCDD/kg/day) obtained from reproductive toxicity and immunotoxicity in rats, and neurobehavioral toxicity and induction of endometriosis in rhesus monkeys are calculated to be the body burden of 10~50 ng TCDD/kg that is 14~37 pg TEQ/kg/day as human daily intake. Finally TDI of 1~4 pg TEQ/kg/day was established by applying the UF of 10. In Japan, reproductive toxicity and immunotoxicity in rats were used to obtain LOAELs (100~200 ng TCDD/kg/day). Finally TDI of 4 pg TEQ/kg/day was established in June 1999 by applying the UF of 10 to human daily intake of 43.6 pg TEQ/kg/day which corresponds to the body burden of 86 ng TCDD/kg.
Kurokawa, Kenji,Jung, Dong-Jun,An, Jang-Hyun,Fuchs, Katharina,Jeon, Yu-Jin,Kim, Na-Hyang,Li, Xuehua,Tateishi, Koichiro,Park, Ji Ae,Xia, Guoqing,Matsushita, Misao,Takahashi, Kazue,Park, Hee-Ju,Peschel, American Society for Biochemistry and Molecular Bi 2013 The Journal of biological chemistry Vol.288 No.43
<P>Serum antibodies and mannose-binding lectin (MBL) are important host defense factors for host adaptive and innate immunity, respectively. Antibodies and MBL also initiate the classical and lectin complement pathways, respectively, leading to opsonophagocytosis. We have shown previously that <I>Staphylococcus aureus</I> wall teichoic acid (WTA), a cell wall glycopolymer consisting of ribitol phosphate substituted with α- or β-<I>O-N</I>-acetyl-<SMALL>d</SMALL>-glucosamine (GlcNAc) and <SMALL>d</SMALL>-alanine, is recognized by MBL and serum anti-WTA IgG. However, the exact antigenic determinants to which anti-WTA antibodies or MBL bind have not been determined. To answer this question, several <I>S. aureus</I> mutants, such as α-GlcNAc glycosyltransferase-deficient <I>S. aureus</I> Δ<I>tarM</I>, β-GlcNAc glycosyltransferase-deficient Δ<I>tarS</I>, and Δ<I>tarMS</I> double mutant cells, were prepared from a laboratory and a community-associated methicillin-resistant <I>S. aureus</I> strain. Here, we describe the unexpected finding that β-GlcNAc WTA-deficient Δ<I>tarS</I> mutant cells (which have intact α-GlcNAc) escape from anti-WTA antibody-mediated opsonophagocytosis, whereas α-GlcNAc WTA-deficient Δ<I>tarM</I> mutant cells (which have intact β-GlcNAc) are efficiently engulfed by human leukocytes via anti-WTA IgG. Likewise, MBL binding in <I>S. aureus</I> cells was lost in the Δ<I>tarMS</I> double mutant but not in either single mutant. When we determined the serum concentrations of the anti-α- or anti-β-GlcNAc-specific WTA IgGs, anti-β-GlcNAc WTA-IgG was dominant in pooled human IgG fractions and in the intact sera of healthy adults and infants. These data demonstrate the importance of the WTA sugar conformation for human innate and adaptive immunity against <I>S. aureus</I> infection.</P>