Kawakami T

References (8)

Title : Effect of hypochlorite oxidation on cholinesterase-inhibition assay of acetonitrile extracts from fruits and vegetables for monitoring traces of organophosphate pesticides - Kitamura_2014_J.Toxicol.Sci_39_71
Author(s) : Kitamura K , Maruyama K , Hamano S , Kishi T , Kawakami T , Takahashi Y , Onodera S
Ref : Journal of Toxicological Sciences , 39 :71 , 2014
Abstract : A reproducible method for monitoring traces of cholinesterase (ChE) inhibitors in acetonitrile extracts from fruits and vegetables is described. The method is based on hypochlorite oxidation and ChE inhibition assay. Four common representative samples of produce were selected from a supermarket to investigate the effect of different matrices on pesticides recoveries and assay precision. The samples were extracted with acetonitrile to prepare them for ChE inhibition assays: if necessary, clean-up was performed using dispersive solid-phase extraction for gas chromatography-mass spectrometry (GC/MS) analyses. Chlorine was tested as an oxidising reagent for the conversion of thiophosphorus pesticides (P=S compounds) into their P=O analogues, which have high ChE-inhibiting activity. Chlorine consumption of individual acetonitrile extracts was determined and was strongly dependent on the individual types of fruits and vegetables. After treating the acetonitrile extracts with an excess hypochlorite at 25 degrees C for 15 min, the ChE-inhibiting activities and detection limits for each chlorine-treated pesticide solution were determined. Matrix composition did not interfere significantly with the determination of the pesticides. Enhanced anti-ChE activities leading to low detection limits (ppb levels) were observed for the chlorine-treated extracts that were spiked with chlorpyrifos, diazinon, fenitrothion, and isoxathion. This combination of oxidative derivatisation and ChE inhibition assays was used successfully to monitor and perform semi-quantitative determination of ChE inhibitors in apple, tomato, cucumber, and strawberry samples.
ESTHER : Kitamura_2014_J.Toxicol.Sci_39_71
PubMedSearch : Kitamura_2014_J.Toxicol.Sci_39_71
PubMedID: 24418711

Title : Enhancement of anti-cholinesterase activity of aqueous samples by hypochlorite oxidation for monitoring traces of organophosphorus pesticides in water - Kanno_2012_J.Toxicol.Sci_37_389
Author(s) : Kanno A , Kawakami T , Takahashi Y , Onodera S
Ref : Journal of Toxicological Sciences , 37 :389 , 2012
Abstract : A reproducible method for monitoring traces of cholinesterase (ChE) inhibitors in aqueous samples is described: the method is based on chemical oxidation and a ChE inhibition assay. Chlorine was tested as an oxidizing reagent for conversion of various thiophosphorus pesticides (P=S compounds) into their P=O analogs, which have higher ChE-inhibiting activity. After treating buffered pesticide solutions (pH 6.0) with chlorine (final concentration less than 10 mg/l) of at 25 degrees C for 15 min, the ChE-inhibiting activities and detection limits for each pesticide were determined. Greater ChE-inhibiting activities, leading to lower detection limits (ppb levels), were observed for the chlorine-treated solutions fortified azinphos methyl, diazinon, isoxathion and ronnel etc. No changes in the ChE-inhibiting activities were observed for carbamate pesticide solutions tested before and after chlorination, but an additive effect showed against ChE when these compounds were mixed with paraoxon in water. This combination of oxidative derivatization and ChE inhibition assay was applied successfully to the detection and determination of ChE inhibitors in natural and drinking water samples.
ESTHER : Kanno_2012_J.Toxicol.Sci_37_389
PubMedSearch : Kanno_2012_J.Toxicol.Sci_37_389
PubMedID: 22467030

Title : The genomic landscape of species divergence in Ficedula flycatchers - Ellegren_2012_Nature_491_756
Author(s) : Ellegren H , Smeds L , Burri R , Olason PI , Backstrom N , Kawakami T , Kunstner A , Makinen H , Nadachowska-Brzyska K , Qvarnstrom A , Uebbing S , Wolf JB
Ref : Nature , 491 :756 , 2012
Abstract : Unravelling the genomic landscape of divergence between lineages is key to understanding speciation. The naturally hybridizing collared flycatcher and pied flycatcher are important avian speciation models that show pre- as well as postzygotic isolation. We sequenced and assembled the 1.1-Gb flycatcher genome, physically mapped the assembly to chromosomes using a low-density linkage map and re-sequenced population samples of each species. Here we show that the genomic landscape of species differentiation is highly heterogeneous with approximately 50 'divergence islands' showing up to 50-fold higher sequence divergence than the genomic background. These non-randomly distributed islands, with between one and three regions of elevated divergence per chromosome irrespective of chromosome size, are characterized by reduced levels of nucleotide diversity, skewed allele-frequency spectra, elevated levels of linkage disequilibrium and reduced proportions of shared polymorphisms in both species, indicative of parallel episodes of selection. Proximity of divergence peaks to genomic regions resistant to sequence assembly, potentially including centromeres and telomeres, indicate that complex repeat structures may drive species divergence. A much higher background level of species divergence of the Z chromosome, and a lower proportion of shared polymorphisms, indicate that sex chromosomes and autosomes are at different stages of speciation. This study provides a roadmap to the emerging field of speciation genomics.
ESTHER : Ellegren_2012_Nature_491_756
PubMedSearch : Ellegren_2012_Nature_491_756
PubMedID: 23103876
Gene_locus related to this paper: fical-u3kcg8 , fical-u3jzm0 , fical-u3jdg9 , fical-u3k1a7 , fical-u3k5s8 , fical-u3k5t1

Title : Cadmium reduces adipocyte size and expression levels of adiponectin and Peg1\/Mest in adipose tissue - Kawakami_2010_Toxicology_267_20
Author(s) : Kawakami T , Sugimoto H , Furuichi R , Kadota Y , Inoue M , Setsu K , Suzuki S , Sato M
Ref : Toxicology , 267 :20 , 2010
Abstract : Adipose tissue dysfunction has been associated with diabetogenic effects. The effects of repeated Cd exposure on adipocytes remain largely unknown. We administered Cd at doses of 0, 5, 10, and 20 micromol/kgbw sc for 2 weeks (3.5 times/week) to mice and assessed the possible alteration of epididymal white adipose tissue (WAT), including histological difference, adipocyte differentiation and functional capacity. Whereas hepatic weight did not differ between the control and Cd-exposed groups, WAT weight, as well as adipose cell mass, significantly decreased in a dose-dependent manner in Cd-treated mice. The Cd concentration in WAT significantly increased in Cd-treated groups after 2 weeks of exposure. Next, we examined the effects of Cd on adipocyte differentiation and hypertrophy. Cd exposure significantly decreased the paternally expressed gene 1/Mesoderm-specific transcript mRNA expression levels. Both peroxisome proliferator-activated receptor gamma2 and CCAAT/enhancer-binding protein alpha mRNA expression levels in WAT tended to decrease in the Cd-treated groups. Next, we determined the effects of Cd exposure on the mRNA expression levels of adipose-derived hormones, such as adiponectin and resistin. The adiponectin mRNA expression level in WAT decreased after both 6h and 2 weeks of exposure to a high dose of Cd, and the reduction in resistin mRNA expression levels was observed after 2 weeks of exposure. These results suggest that Cd exposure causes abnormal adipocyte differentiation, expansion, and function, which might lead to development of insulin resistance, hypertension, and cardiovascular disease.
ESTHER : Kawakami_2010_Toxicology_267_20
PubMedSearch : Kawakami_2010_Toxicology_267_20
PubMedID: 19666079

Title : Serum cytokeratin 18 M30 antigen level and its correlation with nutritional parameters in middle-aged Japanese males with nonalcoholic fatty liver disease (NAFLD) - Tabuchi_2010_J.Nutr.Sci.Vitaminol.(Tokyo)_56_271
Author(s) : Tabuchi M , Tomioka K , Kawakami T , Murakami Y , Hiramatsu M , Itoshima T , Sugawara S , Kawashima A , Okita M , Tsukamoto I
Ref : J Nutr Sci Vitaminol (Tokyo) , 56 :271 , 2010
Abstract : Cytokeratin (CK) 18 M30 antigen has been proposed as a diagnostic marker of nonalcoholic fatty liver disease (NAFLD). We studied serum CK18 M30 antigen level and examined the correlations among CK18 and biological data, dietary intake, and plasma fatty acid composition in middle-aged Japanese males with (NAFLD; n=42) and without NAFLD (control; n=35). NAFLD was diagnosed if subjects showed fatty liver on abdominal ultrasonography and their alcohol consumption was <20 g/d. They were also confirmed to have negative serological results for tests of autoimmune liver disease and hepatitis B and C. In the NAFLD group, body mass index, waist circumference, serum M30 antigen, alanine transaminase (ALT), cholinesterase, triacylglycerol, LDL-cholesterol, and HbA1c were significantly higher than in the control group. In the fatty acid analysis of plasma phospholipids, significantly higher dihomo-gamma-linolenic acid (DGLA), total saturated fatty acids (SFA), and palmitic/linoleic acid ratio as well as lower arachidonic acid/DGLA ratio were observed in the NAFLD group compared with the control group. In the NAFLD group, M30 antigen was correlated positively with serum ALT, plasma DGLA, dietary SFA, and serum TNF-alpha as determined by partial correlation analysis controlled for BMI. On the basis of multivariate regression analysis using a stepwise method, M30 antigen was significantly associated with ALT and plasma DGLA. Regarding the determinants of NAFLD as revealed by logistic regression analysis, a high odds ratio was observed for plasma DGLA. In conclusion, members of the NAFLD group showed higher levels of serum CK18 M30 antigen and M30 antigen was strongly associated with serum ALT and plasma DGLA. Abnormal fatty acid metabolism may be a factor that causes aggravation of NAFLD.
ESTHER : Tabuchi_2010_J.Nutr.Sci.Vitaminol.(Tokyo)_56_271
PubMedSearch : Tabuchi_2010_J.Nutr.Sci.Vitaminol.(Tokyo)_56_271
PubMedID: 21228496

Title : Monitoring of cholinesterase-inhibiting activity in water from the Tone canal, Japan, as a biomarker of ecotoxicity - Kawakami_2008_Ecotoxicology_17_221
Author(s) : Kawakami T , Takezawa A , Nishi I , Watanabe E , Ishizaka M , Eun H , Onodera S
Ref : Ecotoxicology , 17 :221 , 2008
Abstract : The cholinesterase (ChE)-inhibiting activity of water and the concentrations of representative inhibitors were monitored in the Tone canal, Japan, during April to December 2006. The ChE-inhibiting activity, measured by using horse serum as enzyme source, increased from late April to early June, and from September to October. Although the trends in the ChE-inhibiting activity of the samples were consistent with concentration changes of organophosphorus pesticides, ChE-inhibiting activity was not observed in samples replicated on the basis of the chemical concentrations detected. The water samples were treated with chlorine to enhance the ChE-inhibiting activity by conversion of thiophosphate pesticides to phosphate pesticides. The ChE-inhibiting activity increased in almost all the chlorine-treated samples, although organophosphorus pesticides were either not detected or detected in traces in the samples by gas chromatographic-mass spectrometric analysis. These results suggested that assay of ChE-inhibiting activity is important for evaluating the ecotoxicity of environmental water, because toxicological investigations based solely on inhibitor concentrations may underestimate the contamination. Furthermore, the combined method of oxidation by chlorination and the ChE assay is very effective for screening and monitoring of organophosphorus pesticides in environmental water.
ESTHER : Kawakami_2008_Ecotoxicology_17_221
PubMedSearch : Kawakami_2008_Ecotoxicology_17_221
PubMedID: 18202915

Title : CD41+\/CD45+ cells without acetylcholinesterase activity are immature and a major megakaryocytic population in murine bone marrow - Matsumura-Takeda_2007_Stem.Cells_25_862
Author(s) : Matsumura-Takeda K , Sogo S , Isakari Y , Harada Y , Nishioka K , Kawakami T , Ono T , Taki T
Ref : Stem Cells , 25 :862 , 2007
Abstract : Murine megakaryocytes (MKs) are defined by CD41/CD61 expression and acetylcholinesterase (AChE) activity; however, their stages of differentiation in bone marrow (BM) have not been fully elucidated. In murine lineage-negative (Lin(-))/CD45(+) BM cells, we found CD41(+) MKs without AChE activity (AChE(-)) except for CD41(++) MKs with AChE activity (AChE(+)), in which CD61 expression was similar to their CD41 level. Lin(-)/CD41(+)/CD45(+)/AChE(-) MKs could differentiate into AChE(+), with an accompanying increase in CD41/CD61 during in vitro culture. Both proplatelet formation (PPF) and platelet (PLT) production for Lin(-)/CD41(+)/CD45(+)/AChE(-) MKs were observed later than for Lin(-)/CD41(++)/CD45(+)/AChE(+) MKs, whereas MK progenitors were scarcely detected in both subpopulations. GeneChip and semiquantitative polymerase chain reaction analyses revealed that the Lin(-)/CD41(+)/CD45(+)/AChE(-) MKs are assigned at the stage between the progenitor and PPF preparation phases in respect to the many MK/PLT-specific gene expressions, including beta1-tubulin. In normal mice, the number of Lin(-)/CD41(+)/CD45(+)/AChE(-) MKs was 100 times higher than that of AChE(+) MKs in BM. When MK destruction and consequent thrombocytopenia were caused by an antitumor agent, mitomycin-C, Lin(-)/CD41(+)/CD45(+)/AChE(-) MKs led to an increase in AChE(+) MKs and subsequent PLT recovery with interleukin-11 administration. It was concluded that MKs in murine BM at least in part consist of immature Lin(-)/CD41(+)/CD45(+)/AChE(-) MKs and more differentiated Lin(-)/CD41(++)/CD45(+)/AChE(+) MKs. Immature Lin(-)/CD41(+)/CD45(+)/AChE(-) MKs are a major MK population compared with AChE(+) MKs in BM and play an important role in rapid PLT recovery in vivo.
ESTHER : Matsumura-Takeda_2007_Stem.Cells_25_862
PubMedSearch : Matsumura-Takeda_2007_Stem.Cells_25_862
PubMedID: 17420226

Title : Complete sequencing and characterization of 21,243 full-length human cDNAs - Ota_2004_Nat.Genet_36_40
Author(s) : Ota T , Suzuki Y , Nishikawa T , Otsuki T , Sugiyama T , Irie R , Wakamatsu A , Hayashi K , Sato H , Nagai K , Kimura K , Makita H , Sekine M , Obayashi M , Nishi T , Shibahara T , Tanaka T , Ishii S , Yamamoto J , Saito K , Kawai Y , Isono Y , Nakamura Y , Nagahari K , Murakami K , Yasuda T , Iwayanagi T , Wagatsuma M , Shiratori A , Sudo H , Hosoiri T , Kaku Y , Kodaira H , Kondo H , Sugawara M , Takahashi M , Kanda K , Yokoi T , Furuya T , Kikkawa E , Omura Y , Abe K , Kamihara K , Katsuta N , Sato K , Tanikawa M , Yamazaki M , Ninomiya K , Ishibashi T , Yamashita H , Murakawa K , Fujimori K , Tanai H , Kimata M , Watanabe M , Hiraoka S , Chiba Y , Ishida S , Ono Y , Takiguchi S , Watanabe S , Yosida M , Hotuta T , Kusano J , Kanehori K , Takahashi-Fujii A , Hara H , Tanase TO , Nomura Y , Togiya S , Komai F , Hara R , Takeuchi K , Arita M , Imose N , Musashino K , Yuuki H , Oshima A , Sasaki N , Aotsuka S , Yoshikawa Y , Matsunawa H , Ichihara T , Shiohata N , Sano S , Moriya S , Momiyama H , Satoh N , Takami S , Terashima Y , Suzuki O , Nakagawa S , Senoh A , Mizoguchi H , Goto Y , Shimizu F , Wakebe H , Hishigaki H , Watanabe T , Sugiyama A , Takemoto M , Kawakami B , Watanabe K , Kumagai A , Itakura S , Fukuzumi Y , Fujimori Y , Komiyama M , Tashiro H , Tanigami A , Fujiwara T , Ono T , Yamada K , Fujii Y , Ozaki K , Hirao M , Ohmori Y , Kawabata A , Hikiji T , Kobatake N , Inagaki H , Ikema Y , Okamoto S , Okitani R , Kawakami T , Noguchi S , Itoh T , Shigeta K , Senba T , Matsumura K , Nakajima Y , Mizuno T , Morinaga M , Sasaki M , Togashi T , Oyama M , Hata H , Komatsu T , Mizushima-Sugano J , Satoh T , Shirai Y , Takahashi Y , Nakagawa K , Okumura K , Nagase T , Nomura N , Kikuchi H , Masuho Y , Yamashita R , Nakai K , Yada T , Ohara O , Isogai T , Sugano S
Ref : Nat Genet , 36 :40 , 2004
Abstract : As a base for human transcriptome and functional genomics, we created the "full-length long Japan" (FLJ) collection of sequenced human cDNAs. We determined the entire sequence of 21,243 selected clones and found that 14,490 cDNAs (10,897 clusters) were unique to the FLJ collection. About half of them (5,416) seemed to be protein-coding. Of those, 1,999 clusters had not been predicted by computational methods. The distribution of GC content of nonpredicted cDNAs had a peak at approximately 58% compared with a peak at approximately 42%for predicted cDNAs. Thus, there seems to be a slight bias against GC-rich transcripts in current gene prediction procedures. The rest of the cDNAs unique to the FLJ collection (5,481) contained no obvious open reading frames (ORFs) and thus are candidate noncoding RNAs. About one-fourth of them (1,378) showed a clear pattern of splicing. The distribution of GC content of noncoding cDNAs was narrow and had a peak at approximately 42%, relatively low compared with that of protein-coding cDNAs.
ESTHER : Ota_2004_Nat.Genet_36_40
PubMedSearch : Ota_2004_Nat.Genet_36_40
PubMedID: 14702039
Gene_locus related to this paper: human-ABHD1 , human-ABHD4 , human-ABHD12 , human-ABHD16A , human-ACOT1 , human-LDAH , human-ABHD18 , human-CES1 , human-CES4A , human-CES5A , human-CPVL , human-DAGLB , human-EPHX2 , human-KANSL3 , human-LIPA , human-LPL , human-MEST , human-NDRG1 , human-NLGN1 , human-NLGN4X , human-PRCP , human-PRSS16 , human-SERAC1 , human-TMEM53