400 results on '"T Kimura"'
Search Results
2. Muscle Stem Cell Function Is Impaired in β2-Adrenoceptor Knockout Mice
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Tatiana E, Koike, Cesar S, Fuziwara, Patricia C, Brum, Edna T, Kimura, Thomas A, Rando, and Elen H, Miyabara
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Mice, Knockout ,Mice ,Satellite Cells, Skeletal Muscle ,Muscles ,Animals ,Myogenin ,Wnt Signaling Pathway ,beta Catenin ,Receptors, Adrenergic - Abstract
Knockout (ko) mice for the β2 adrenoceptor (Adrβ2) have impaired skeletal muscle regeneration, suggesting that this receptor is important for muscle stem cell (satellite cell) function. Here, we investigated the role of Adrβ2 in the function of satellite cells from β2ko mice in the context of muscle regeneration, through in vivo and in vitro experiments. Immunohistochemical analysis showed a significant reduction in the number of self-renewed Pax7
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- 2022
3. DROP: Molecular voucher database for identification of Drosophila parasitoids
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Jeff Leips, Mariana Mateos, Nicholas A. Pardikes, Robert R. Kula, Yves Carton, Julien Varaldi, Todd A. Schlenke, Owen T. Lewis, Chia-Hua Lue, Phillip P. A. Staniczenko, Paul Z. Goldstein, Kent M. Daane, Emilio Guerrier, Amy C. Driskell, Sonja Scheffer, Massimo Giorgini, Melanie Thierry, Francis M. Jiggins, Scott E. Miller, Matthew L. Buffington, Joel J. Brown, Bregje Wertheim, Anna Jandová, Dan Tracey, Paul K. Abram, Kim A. Hoelmer, Masahito T. Kimura, Marylène Poirié, Shubha Govind, Xin-Geng Wang, Jeremy S Davis, Jan Hrcek, Matthew Lewis, Amelia R.I. Lindsey, Tyler A. Elliott, Wertheim lab, Biology Centre of the Czech Academy of Sciences (BIOLOGY CENTRE CAS), Czech Academy of Sciences [Prague] (CAS), City University of New York [New York] (CUNY), National Museum of Natural History [Washington], University of Guelph, Department of Anthropology [University of Minnesota], University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, Hokkaido University Museum, Hokkaido University [Sapporo, Japan], Evolution, génomes, comportement et écologie (EGCE), Institut de Recherche pour le Développement (IRD)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA), Grant Agency of the Czech Republic17-27184Y, and Czech Science Foundation
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0106 biological sciences ,0301 basic medicine ,redox homeostasis ,Food Chain ,biological control ,DNA sequences ,computer.software_genre ,[SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy ,010603 evolutionary biology ,01 natural sciences ,Genome ,plant symbiosis ,DNA sequencing ,molecular diagnostics ,03 medical and health sciences ,Type (biology) ,Genetics ,Animals ,diazotrophs ,Drosophila suzukii ,bacteria ,Drosophila ,Ecology, Evolution, Behavior and Systematics ,integrative taxonomy ,030304 developmental biology ,0303 health sciences ,biology ,Database ,fungi ,ROS ,Biodiversity ,biology.organism_classification ,Molecular diagnostics ,Voucher ,[SDV.BA.ZI]Life Sciences [q-bio]/Animal biology/Invertebrate Zoology ,030104 developmental biology ,GenBank ,Identification (biology) ,genomes ,computer ,Biotechnology - Abstract
Molecular identification is increasingly used to speed up biodiversity surveys and laboratory experiments. However, many groups of organisms cannot be reliably identified using standard databases such as GenBank or BOLD due to lack of sequenced voucher specimens identified by experts. Sometimes a large number of sequences are available, but with too many errors to allow identification. Here we address this problem for parasitoids of Drosophila by introducing a curated open-access molecular reference database, DROP (Drosophilaparasitoids). Identifying Drosophila parasitoids is challenging and poses a major impediment to realize the full potential of this model system in studies ranging from molecular mechanisms to food webs, and in biological control of Drosophila suzukii. In DROP (http://doi.org/10.5281/zenodo.4519656), genetic data are linked to voucher specimens and, where possible, the voucher specimens are identified by taxonomists and vetted through direct comparison with primary type material. To initiate DROP, we curated 154 laboratory strains, 856 vouchers, 554 DNA sequences, 16 genomes, 14 transcriptomes, and 6 proteomes drawn from a total of 183 operational taxonomic units (OTUs): 114 described Drosophila parasitoid species and 69 provisional species. We found species richness of Drosophila parasitoids to be heavily underestimated and provide an updated taxonomic catalogue for the community. DROP offers accurate molecular identification and improves cross-referencing between individual studies that we hope will catalyze research on this diverse and fascinating model system. Our effort should also serve as an example for researchers facing similar molecular identification problems in other groups of organisms.
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- 2021
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4. Intense browsing by sika deer (Cervus nippon) drives the genetic differentiation of hairy nettle (Urtica thunbergiana) populations
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Tetsuo I, Kohyama, Mei, Yoshida, Masahito T, Kimura, and Hiroaki, Sato
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Genotype ,Japan ,Deer ,Genetic Drift ,Animals ,Genetic Variation ,Bayes Theorem ,Herbivory ,Amplified Fragment Length Polymorphism Analysis ,Urticaceae - Abstract
Many studies have inferred the way in which natural selection, genetic drift and gene flow shape the population genetic structures, but very few have quantified the population differentiation under spatially and temporally varying levels of selection pressure, population fluctuation and gene flow. In Nara Park (6.6 km
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- 2021
5. The Glucagon-Like Peptide-1 Receptor Agonist Liraglutide Improves Hypoxia-Induced Pulmonary Hypertension in Mice Partly via Normalization of Reduced ETB Receptor Expression
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Takashi Miyauchi, Kazutaka Aonuma, Junya Honda, Satoshi Sakai, Hidekazu Maruyama, Satoshi Homma, Nobuyuki Murakoshi, Kazuko Tajiri, and T. Kimura
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Male ,0301 basic medicine ,Agonist ,medicine.medical_specialty ,Physiology ,medicine.drug_class ,Hypertension, Pulmonary ,Receptor expression ,Gene Expression ,Glucagon-Like Peptide-1 Receptor ,Mice ,03 medical and health sciences ,Internal medicine ,Animals ,Hypoglycemic Agents ,Medicine ,Hypoxia ,Receptor ,Glucagon-like peptide 1 receptor ,business.industry ,Liraglutide ,General Medicine ,Hypoxia (medical) ,medicine.disease ,Receptor, Endothelin B ,Pulmonary hypertension ,Mice, Inbred C57BL ,030104 developmental biology ,Endocrinology ,medicine.symptom ,business ,Endothelin receptor ,medicine.drug - Abstract
The glucagon-like peptide-1 receptor (GLP-1R) agonist liraglutide is an incretin hormone mimetic used in the treatment of diabetes. However, the effects of liraglutide on pulmonary hypertension (PH) and pulmonary endothelin (ET) system are unknown. Eight-week-old C57BL6/J mice were injected liraglutide or vehicle for 5 weeks. One week after injection, the mice were exposed to either room air (normoxia) or chronic hypoxia (10 % O2) for 4 weeks. The right ventricular systolic pressure (RVSP) was significantly higher in hypoxia + vehicle group than in normoxia + vehicle group. ET-1 mRNA expression in the lungs was comparable among all the groups. ETB mRNA and protein expression in the lungs was significantly lower in hypoxia + vehicle group than in normoxia + vehicle group. The above changes were normalized by liraglutide treatment. The expression of phospho-eNOS and phospho-AMPK proteins in the lungs was significantly higher in hypoxia + liraglutide group than in normoxia + vehicle group. We demonstrated for the first time that liraglutide effectively improved RVSP and RV hypertrophy in hypoxia-induced PH mice by activating eNOS through normalization of impaired ETB pathway and augmentation of AMPK pathway. Therefore, GLP-1R agonists can be promising therapeutic agents for PH.
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- 2018
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6. Related herbivore species show similar temporal dynamics
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Sofia Gripenberg, Riikka Kaartinen, Masahito T. Kimura, Ayco J. M. Tack, F. Guillaume Blanchet, Tea Huotari, Tomas Roslin, and Tylianakis, Jason
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0106 biological sciences ,Herbivore ,Insecta ,Phylogenetic tree ,Ecology ,010604 marine biology & hydrobiology ,Voltinism ,Rare species ,Community structure ,15. Life on land ,010603 evolutionary biology ,01 natural sciences ,Quercus ,Taxon ,Japan ,Phylogenetics ,Guild ,Animals ,Animal Science and Zoology ,Herbivory ,Life History Traits ,Finland ,Phylogeny ,Ecology, Evolution, Behavior and Systematics - Abstract
1. Within natural communities, different taxa display different dynamics in time. Why this is the case we do not fully know. This thwarts our ability to predict changes in community structure, which is important for both the conservation of rare species in natural communities and for the prediction of pest outbreaks in agriculture 2. Species sharing phylogeny, natural enemies and/or life history traits have been hypothesized to share similar temporal dynamics. We operationalized these concepts into testing whether feeding guild, voltinism, similarity in parasitoid community, and/or phylogenetic relatedness explained similarities in temporal dynamics among herbivorous community members. 3. Focusing on two similar data sets from different geographical regions (Finland and Japan), we used asymmetric eigenvector maps as temporal variables to characterize species- and community-level dynamics of specialist insect herbivores on oak (Quercus). We then assessed whether feeding guild, voltinism, similarity in parasitoid community, and/or phylogenetic relatedness explained similarities in temporal dynamics among taxa. 4. Species-specific temporal dynamics varied widely, ranging from directional decline or increase to more complex patterns. Phylogeny was a clear predictor of similarity in temporal dynamics at the Finnish site, whereas for the Japanese site, the data were uninformative regarding a phylogenetic imprint. Voltinism, feeding guild and parasitoid overlap explained little variation at either location. Despite the rapid temporal dynamics observed at the level of individual species, these changes did not translate into any consistent temporal changes at the community level in either Finland or Japan. 5. Overall, our findings offer no direct support for the notion that species sharing natural enemies and/or life history traits would be characterised by similar temporal dynamics, but reveal a strong imprint of phylogenetic relatedness. As this phylogenetic signal cannot be attributed to guild, voltinism or parasitoids, it will likely derive from shared microhabitat, microclimate, anatomy, physiology or behaviour. This has important implications for predicting insect outbreaks and for informing insect conservation. We hope that future studies will assess the generality of our findings across plant-feeding insect communities and beyond, and establish the more precise mechanism(s) underlying the phylogenetic imprint.
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- 2018
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7. The parasitoid complex of D. suzukii and other fruit feeding Drosophila species in Asia
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Alexandre Aebi, Francisco Javier Peris-Felipo, Pierre Girod, Hao Wu, Jinping Zhang, Matthew L. Buffington, Tim Haye, Nicolas Ris, Guohua Chen, Masahito T. Kimura, Yuan Fang, Marc Kenis, Nicolas Borowiec, Chun Xiao, CABI Europe Switzerland, Université de Neuchâtel (UNINE), Institut Sophia Agrobiotech (ISA), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut National de la Recherche Agronomique (INRA), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), European Biological Control Laboratory, USDA-ARS (EBCL - USDA ARS), Yunnan Agricultural University, Independent Artist, Chinese Academy of Agricultural Sciences (CAAS), European Project: 613678,EC:FP7:KBBE,FP7-KBBE-2013-7-single-stage,DROPSA(2014), Institut National de la Recherche Agronomique (INRA)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), and Kenis, Marc
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0106 biological sciences ,China ,food.ingredient ,[SDV]Life Sciences [q-bio] ,Wasps ,Biological pest control ,lcsh:Medicine ,Parasitism ,Zoology ,Leptopilina ,010603 evolutionary biology ,01 natural sciences ,Article ,Host Specificity ,Parasitoid ,Host-Parasite Interactions ,food ,Japan ,Animals ,lcsh:Science ,Drosophila suzukii ,Pest Control, Biological ,Asobara ,Multidisciplinary ,biology ,Geography ,Ants ,lcsh:R ,Figitidae ,biology.organism_classification ,010602 entomology ,Fruit ,Larva ,[SDE]Environmental Sciences ,lcsh:Q ,Drosophila ,Braconidae - Abstract
Drosophila suzukii is an invasive fly of East Asian origin that has become a serious fruit pest worldwide. Classical biological control through the introduction of parasitoids from Asia could help reduce populations of D. suzukii in invaded regions. Little is known about the native parasitoids of the fly in Asia. Therefore, surveys for larval parasitoids of D. suzukii were carried out in China and Japan between 2015 and 2017. Parasitoids of D. suzukii and other fruit-inhabiting drosophilids (D. pulchrella and D. subpulchrella) that are probably attacked by the same parasitoid complex were found in four Chinese provinces and four Japanese prefectures. Larval parasitoids were obtained at most sites where D. suzukii was found, with parasitism varying from 0.0 to 75.6%. At least eight parasitoid species were reared. The most abundant and frequent parasitoids were the Figitidae Ganaspis cf. brasiliensis and Leptopilina japonica, but another Leptopilina species and at least five Braconidae species belonging to the genera Areotetes, Asobara and Tanycarpa were obtained in low numbers. Due to its likely restricted host range, the most promising parasitoid for biological control is Ganaspis cf. brasiliensis. However, its exact specificity and taxonomic status require future research.
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- 2018
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8. Identification of a novel E‐box binding pyrrole‐imidazole polyamide inhibiting <scp>MYC</scp> ‐driven cell proliferation
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Carla Grandori, Masayoshi Soma, Narendra Kumar Verma, Tsugumichi Koshinaga, Jin Takeuchi, Rajeev Mishra, Hiroki Nagase, Xiaofei Wang, Jun Igarashi, Shota Uekusa, Norimichi Nemoto, Nobuko Koshikawa, Takeshi Kusafuka, Yujin Kobayashi, Christopher J. Kemp, Takayoshi Watanabe, Diptiman Choudhury, Noboru Fukuda, Miki Ohira, Maki Ikeda, Kyoko Fujiwara, Makoto T. Kimura, and Hiroyuki Kawashima
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Cancer Research ,Apoptosis ,MYC ,Mice, SCID ,Cell cycle ,Biology ,transcription therapy ,E-Box Elements ,Proto-Oncogene Proteins c-myc ,Mice ,pyrrole-imidazole polyamide ,Cyclin D1 ,Cell Line, Tumor ,Gene expression ,Consensus sequence ,Animals ,Humans ,Pyrroles ,E-box binding ,Promoter Regions, Genetic ,Gene ,Cell Proliferation ,Binding Sites ,Cell growth ,Imidazoles ,Cyclin-Dependent Kinase 4 ,Promoter ,Original Articles ,General Medicine ,Burkitt Lymphoma ,Xenograft Model Antitumor Assays ,3. Good health ,DNA-Binding Proteins ,Nylons ,Oncology ,E-Box ,Cancer research ,Eukaryotic Initiation Factor-4G ,Protein Binding ,K562 cells - Abstract
The MYC transcription factor plays a crucial role in the regulation of cell cycle progression, apoptosis, angiogenesis, and cellular transformation. Due to its oncogenic activities and overexpression in a majority of human cancers, it is an interesting target for novel drug therapies. MYC binding to the E-box (5'-CACGTGT-3') sequence at gene promoters contributes to more than 4000 MYC-dependent transcripts. Owing to its importance in MYC regulation, we designed a novel sequence-specific DNA-binding pyrrole-imidazole (PI) polyamide, Myc-5, that recognizes the E-box consensus sequence. Bioinformatics analysis revealed that the Myc-5 binding sequence appeared in 5'- MYC binding E-box sequences at the eIF4G1, CCND1, and CDK4 gene promoters. Furthermore, ChIP coupled with detection by quantitative PCR indicated that Myc-5 has the ability to inhibit MYC binding at the target gene promoters and thus cause downregulation at the mRNA level and protein expression of its target genes in human Burkitt's lymphoma model cell line, P493.6, carrying an inducible MYC repression system and the K562 (human chronic myelogenous leukemia) cell line. Single i.v. injection of Myc-5 at 7.5 mg/kg dose caused significant tumor growth inhibition in a MYC-dependent tumor xenograft model without evidence of toxicity. We report here a compelling rationale for the identification of a PI polyamide that inhibits a part of E-box-mediated MYC downstream gene expression and is a model for showing that phenotype-associated MYC downstream gene targets consequently inhibit MYC-dependent tumor growth.
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- 2015
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9. Polyunsaturated fatty acid deficiency during neurodevelopment in mice models the prodromal state of schizophrenia through epigenetic changes in nuclear receptor genes
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Takeo Yoshikawa, Chie Shimamoto, Manabu Toyoshima, Hisako Ohba, Yasuko Hisano, T Kimura, Shabeesh Balan, Kei Hamazaki, Akiko Watanabe, Kazuya Iwamoto, Motoko Maekawa, Yayoi Nozaki, E Takahashi, Akihiko Takashima, Miki Bundo, Tetsuo Ohnishi, Yoshimi Iwayama, and Noriko Osumi
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0301 basic medicine ,medicine.medical_specialty ,Docosahexaenoic Acids ,Offspring ,Peroxisome proliferator-activated receptor ,Prefrontal Cortex ,Prodromal Symptoms ,Receptors, Cytoplasmic and Nuclear ,Retinoid X receptor ,Biology ,Epigenesis, Genetic ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Pregnancy ,Internal medicine ,medicine ,Animals ,Cognitive Dysfunction ,Biological Psychiatry ,chemistry.chemical_classification ,Arachidonic Acid ,Behavior, Animal ,Milk, Human ,Malnutrition ,Oligodendrocyte ,Mice, Inbred C57BL ,Pregnancy Complications ,Psychiatry and Mental health ,Disease Models, Animal ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,Nuclear receptor ,chemistry ,Animals, Newborn ,Docosahexaenoic acid ,Prenatal Exposure Delayed Effects ,Schizophrenia ,Arachidonic acid ,lipids (amino acids, peptides, and proteins) ,Female ,Original Article ,030217 neurology & neurosurgery ,Polyunsaturated fatty acid - Abstract
The risk of schizophrenia is increased in offspring whose mothers experience malnutrition during pregnancy. Polyunsaturated fatty acids (PUFAs) are dietary components that are crucial for the structural and functional integrity of neural cells, and PUFA deficiency has been shown to be a risk factor for schizophrenia. Here, we show that gestational and early postnatal dietary deprivation of two PUFAs—arachidonic acid (AA) and docosahexaenoic acid (DHA)—elicited schizophrenia-like phenotypes in mouse offspring at adulthood. In the PUFA-deprived mouse group, we observed lower motivation and higher sensitivity to a hallucinogenic drug resembling the prodromal symptoms in schizophrenia. Furthermore, a working-memory task-evoked hyper-neuronal activity in the medial prefrontal cortex was also observed, along with the downregulation of genes in the prefrontal cortex involved in oligodendrocyte integrity and the gamma-aminobutyric acid (GABA)-ergic system. Regulation of these genes was mediated by the nuclear receptor genes Rxr and Ppar, whose promoters were hyper-methylated by the deprivation of dietary AA and DHA. In addition, the RXR agonist bexarotene upregulated oligodendrocyte- and GABA-related gene expression and suppressed the sensitivity of mice to the hallucinogenic drug. Notably, the expression of these nuclear receptor genes were also downregulated in hair-follicle cells from schizophrenia patients. These results suggest that PUFA deficiency during the early neurodevelopmental period in mice could model the prodromal state of schizophrenia through changes in the epigenetic regulation of nuclear receptor genes.
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- 2017
10. Left Ventricular Strain and Transmural Distribution of Structural Remodeling in Hypertensive Heart Disease
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T. Kimura, Nobutake Shimojo, Yoshihiro Seo, Nobuyuki Murakoshi, Tomoko Ishizu, Yuri Kameda, Dongzhu Xu, Kazutaka Aonuma, and Ryo Kawamura
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Male ,medicine.medical_specialty ,Heart Ventricles ,Diastole ,Blood Pressure ,Speckle tracking echocardiography ,Muscle hypertrophy ,Heart Rate ,Fibrosis ,Internal medicine ,Internal Medicine ,medicine ,Animals ,Ventricular remodeling ,Heart Failure ,Rats, Inbred Dahl ,Ventricular Remodeling ,business.industry ,Stroke Volume ,medicine.disease ,Hypertensive heart disease ,Rats ,Disease Models, Animal ,Blood pressure ,Echocardiography ,Heart failure ,Hypertension ,Cardiology ,business - Abstract
Left ventricular (LV) systolic wall strain is a new candidate for prognostic indicator of hypertensive heart failure. It remains unclear how underlying transmural structural remodeling corresponds to LV wall systolic deformation as hypertensive hypertrophy progresses. We fed 68 Dahl salt–sensitive rats a high-salt (hypertensive group) or low-salt diet (control group) from 6 weeks old. At 10, 14, and 18 weeks, pressure–volume relation, transmural distribution of LV fibrosis, and myocyte hypertrophy were evaluated. LV global longitudinal and circumferential strain was measured with speckle tracking echocardiography. Emax was preserved throughout the study period, whereas τ and end-diastolic pressure–volume relation progressively deteriorated from 14 weeks (diastolic dysfunction stage). Lung weight increased significantly at 18 weeks (decompensated stage). Histological percentage area fibrosis and collagen type I/III, myocyte hypertrophy, and α-myosin heavy chain isoform increased in the subendocardial layer at 14 weeks and progressed into the midlayer at 18 weeks. Longitudinal strain progressively deteriorated in the hypertensive group versus control group at 14 weeks (hypertensive group: −17±3%, control: −27±4%; P P =0.002). After adjustment for systolic wall stress, subendocardial percentage area fibrosis was selected as the independent determinant of longitudinal strain. This study showed that LV wall strain alternations were accompanied by fibrosis and myocyte hypertrophy from subendocardium to epicardium, and longitudinal strain related significantly to subendocardial layer fibrosis. Longitudinal strain could be a surrogate of subendocardial fibrotic changes and may be useful for risk stratification of hypertensive heart failure.
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- 2014
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11. Semen Collection and Polymerase Chain Reaction-Based Sex Determination of Black-Headed and Straw-Necked Ibis
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Takahisa Yamada, Bin Tong, Hiroaki Iwaisaki, Hideaki Yamashiro, S Yamagishi, Yuichi Wajiki, Toshie Sugiyama, Y Takahashi, T Kimura, K Kaneko, Y Kaneko, Sachio Takino, and Emi Uematsu
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Male ,Ibis ,Sex Determination Analysis ,Semen ,Sexing ,Biology ,biology.organism_classification ,Polymerase Chain Reaction ,Spermatozoa ,Sperm ,Semen collection ,Specimen Handling ,law.invention ,Birds ,Andrology ,Endocrinology ,law ,Animals ,Female ,Animal Science and Zoology ,Acrosome ,Polymerase chain reaction ,Biotechnology - Abstract
This study aimed to develop a polymerase chain reaction (PCR)-based sexing and effective semen collection methods for black-headed and straw-necked ibis species. However, most birds are not sexually dimorphic, that is, the sexes appear similar. Therefore, the gender should be determined before semen collection. DNA was extracted from the blood samples of 11 black-headed and 4 straw-necked ibis. The sex was determined after PCR amplification of the EE0.6 region of W-chromosome. The PCR products were separated using gel electrophoresis. A single band indicated the presence of the EE0.6 region and that the individual was a female, while no band indicated that the individual was a male. Further, the single bands from seven specimens were amplified. Semen collection was performed by massage or a combination of massage with electro-ejaculation and was attempted during all four seasons. The semen was successfully collected in March from male straw-necked ibis using the massage method. Limited motility, viability and concentration of straw-necked ibis sperm were observed. The sperm length was 180 μm and that of the nucleus was 30 μm with acrosome located at the tip of the nucleus. Thus, the PCR-based sexing proved to be an accurate molecular sexing method for black-headed and straw-necked ibis. Furthermore, we successfully collected semen and observed the stained sperm nucleus and acrosome of the straw-necked ibis sperm. We propose that the use of this PCR methodology can be applied as a routine method for sex determination and semen collection in ibis species for future ecological research. However, considering our limited success, further studies on semen collection method are required.
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- 2013
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12. Pretranscriptional Regulation of Tgf-β1 by PI Polyamide Prevents Scarring and Accelerates Wound Healing of the Cornea After Exposure to Alkali
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Noboru Fukuda, Xiaofei Wang, Hiroki Nagase, Linghua Wang, Hiroyuki Matsuda, Jun Igarashi, Min Chen, Takayoshi Watanabe, Tohru Sakimoto, Mitsuru Sawa, and Makoto T. Kimura
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Stromal cell ,Pharmacology ,Cornea ,Transforming Growth Factor beta1 ,Cicatrix ,Downregulation and upregulation ,Drug Discovery ,Genetics ,medicine ,Animals ,Humans ,Pyrroles ,RNA, Messenger ,Promoter Regions, Genetic ,Molecular Biology ,Wound Healing ,Binding Sites ,Corneal Haze ,Dose-Response Relationship, Drug ,Activator (genetics) ,Chemistry ,HEK 293 cells ,Imidazoles ,Original Articles ,Anatomy ,eye diseases ,Rats ,Nylons ,medicine.anatomical_structure ,Gene Expression Regulation ,Molecular Medicine ,sense organs ,Wound healing ,Transforming growth factor - Abstract
Corneal alkali burns are a serious clinical problem that often leads to permanent visual impairment. In this process, transforming growth factor (Tgf)-beta1 is upregulated and involved in the response to corneal injury and the process of corneal stromal scarring. To develop an efficient compound to inhibit Tgf-beta1 in the cornea, we designed GB1201, a pyrrole-imidazole (PI) polyamide targeting rat Tgf-beta1 gene promoter to the activator protein-1 (AP-1) binding site. GB1201 showed a high binding affinity to the target DNA sequence in the gel mobility shift and Biacore assays. GB1201 significantly inhibited the rat Tgf-beta1 gene promoter activity in HEK (human embryonic kidney) 293 cells in a concentration-dependent manner. Topically administrated GB1201 was distributed immediately to the nuclei of all cell layers of the cornea and remained for 24 hours. A corneal alkali burn model in rats was used to evaluate the therapeutic efficacy of GB1201. GB1201 suppressed the upregulation of Tgf-beta1 in the burned cornea, both in the mRNA and protein levels. Moreover, daily treatment with GB1201 for a week significantly improved the corneal tissue wound healing, reduced corneal stromal scarring, and prevented corneal haze formation. Our data suggest that PI polyamide may open new opportunities for therapeutic intervention in the treatment of chemically burned corneas.
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- 2010
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13. In vivo dynamics of human cord blood-derived CD34− SCID-repopulating cells using intra-bone marrow injection
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T Kimura, Y Matsuoka, M Murakami, M Takahashi, T Nakamoto, K Yasuda, K Matsui, K Kobayashi, S Imai, H Asano, R Nakatsuka, Y Uemura, Y Sasaki, and Y Sonoda
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Cancer Research ,Cell Separation ,Mice, SCID ,CD38 ,Biology ,Mice ,Cell Movement ,Mice, Inbred NOD ,immune system diseases ,hemic and lymphatic diseases ,medicine ,Animals ,Humans ,Bone Marrow Transplantation ,Severe combined immunodeficiency ,Leukosialin ,Hematopoietic stem cell ,hemic and immune systems ,Hematology ,Fetal Blood ,Hematopoietic Stem Cells ,medicine.disease ,ADP-ribosyl Cyclase 1 ,Cell biology ,Transplantation ,medicine.anatomical_structure ,Oncology ,Cord blood ,Immunology ,SCID-Repopulating Cell ,Female ,Bone marrow ,Stem cell - Abstract
The identification of human CD34-negative (CD34(-)) hematopoietic stem cells (HSCs) provides a new concept for the hierarchy in the human HSC compartment. This study investigated the long-term repopulating capacity and redistribution kinetics of human cord blood-derived CD34(-) severe combined immunodeficiency (SCID)-repopulating cells (SRCs) and compared them with those of CD34(+)CD38(+) and CD34(+)CD38(-) SRCs using the intra-bone marrow injection (IBMI) to clarify the characteristics of CD34(-) SRCs. On the basis of the limiting dilution analyses data, estimated numbers of CD34(+)CD38(+), CD34(+)CD38(-), and CD34(-) SRCs were transplanted to NOD/SCID mice by IBMI. The human cell repopulation at the site of injection and the other bones were serially investigated. Interestingly, CD34(+)CD38(+), CD34(+)CD38(-), and CD34(-) SRCs began to migrate to other bones 2 and 5 weeks after the transplantation, respectively. Accordingly, the initiation of migration seemed to differ between the CD34(+) and CD34(-) SRCs. In addition, CD34(+)CD38(+) SRCs only sustained a short-term repopulation. However, both CD34(+)CD38(-) and CD34(-) SRCs had longer-term repopulation capacity. Taken together, these findings showed that CD34(-) SRCs show different in vivo kinetics, thus suggesting that the identified CD34(-) SRCs are a distinct class of primitive HSCs in comparison to the CD34(+)CD38(+) and CD34(+)CD38(-) SRCs.
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- 2009
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14. An oro-facial disease ‘noma (cancrum oris)’ in a Japanese monkey (Macaca fuscata): clinical signs, clinicopathological features, and response to treatment
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T. Kimura
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Male ,Pathology ,medicine.medical_specialty ,Basic fibroblast growth factor ,Noma ,Disease ,Simian ,medicine.disease_cause ,chemistry.chemical_compound ,medicine ,Animals ,General Veterinary ,biology ,Streptococcus ,Monkey Diseases ,Simian immunodeficiency virus ,biology.organism_classification ,medicine.disease ,Blood Cell Count ,chemistry ,Face ,biology.protein ,Macaca ,Female ,Animal Science and Zoology ,Creatine kinase ,Antibody - Abstract
Background A Japanese monkey developed severe oro-facial lesions that were called noma in humans. Although extensive destruction of both the buccal regions occurred with rapid progress, author successfully treated the lesions with povidone-iodine, enrofloxacin, chymotrypsin, a glycyrrhizin preparation, and a basic fibroblast growth factor. Methods Author clinicopathologically investigated this disease during the treatment. Results In the subcutaneous and muscular tissues, the lesions developed characteristic changes such as dissolving collagen fibers and muscular tissues phagocytosed by giant and epitheloid cells. The monkey showed a notable increase in creatine kinase activities. The present examinations revealed severe invasive findings in muscular tissues, which were accompanied by infections of β-hemolytic streptococcus Group C. This monkey was negative for simian immunodeficiency virus antibody; however, infection with simian D retrovirus was not ruled out. Conclusions Simian noma was a rapidly devastating disease, which destroyed the muscle tissues of oro-facial structure. Nonhuman primates are the only species that develop oro-facial lesions, corresponding to noma in humans.
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- 2008
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15. Development and characterization of immobilized human organic anion transporter-based liquid chromatographic stationary phase: hOAT1 and hOAT2
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J. Perry, Ruin Moaddel, T. Kimura, J.B. Pritchard, and N. Anzai
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Chromatography ,biology ,Organic anion transporter 1 ,Chemistry ,Ligand ,Clinical Biochemistry ,Synthetic membrane ,Organic Anion Transport Protein 1 ,Transporter ,Cell Biology ,General Medicine ,Plasma protein binding ,Organic Anion Transporters, Sodium-Independent ,Biochemistry ,Article ,Chromatography, Affinity ,Cell Line ,Analytical Chemistry ,Affinity chromatography ,biology.protein ,Animals ,Chromatography, Liquid ,Protein Binding ,Organic anion - Abstract
This paper reports the development of liquid chromatographic columns containing immobilized organic anion transporters (hOAT1, hOAT2). Cellular membrane fragments from MDCK cells expressing hOAT1 and S2 cells expressing hOAT2 were immobilized on the surface of the immobilized artificial membrane (IAM) liquid chromatographic stationary phase. The resulting stationary phases were characterized by frontal affinity chromatography, using the marker ligand [ 3 H]-adefovir for the hOAT1 and [ 14 C]- p-aminohippurate for the hOAT2 in the presence of multiple displacers. The determined binding affinities (Kd) for eight OAT1 ligands and eight OAT2 ligands were correlated with literature values and a statistically significant correlation was obtained for both the hOAT1 and hOAT2 columns: r2= 0.688 (p < 0.05) and r2=0.9967 (p
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- 2007
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16. Phylogeography, Interaction Patterns and the Evolution of Host Choice in Drosophila-Parasitoid Systems in Ryukyu Archipelago and Taiwan
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Biljana Novković and Masahito T. Kimura
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Gene Flow ,Science ,Wasps ,Taiwan ,Population genetics ,Biology ,Leptopilina ,Gene flow ,Coalescent theory ,Host-Parasite Interactions ,chemistry.chemical_compound ,Species Specificity ,Molecular marker ,Animals ,Drosophila Proteins ,Phylogeny ,geography ,Multidisciplinary ,geography.geographical_feature_category ,Phylogenetic tree ,fungi ,DNA ,biology.organism_classification ,Biological Evolution ,Phylogeography ,chemistry ,Evolutionary biology ,Archipelago ,Medicine ,Drosophila ,Research Article - Abstract
Island biotas provide a great opportunity to study not only the phylogeographic patterns of a group of species, but also to explore the differentiation in their coevolutionary interactions. Drosophila and their parasitoids are exemplary systems for studying complex interaction patterns. However, there is a lack of studies combining interaction-based and molecular marker-based methods. We applied an integrated approach combining phylogeography, interaction, and host-choice behavior studies, with the aim to understand how coevolutionary interactions evolve in Drosophila-parasitoid island populations. The study focused on the three most abundant Drosophila species in Ryukyu archipelago and Taiwan: D. albomicans, D. bipectinata, and D. takahashii, and the Drosophila-parasitoid Leptopilina ryukyuensis. We determined mitochondrial COI haplotypes for samples representing five island populations of Drosophila and four island populations of L. ryukyuensis. We additionally sequenced parts of the autosomal Gpdh for Drosophila samples, and the ITS2 for parasitoid samples. Phylogenetic and coalescent analyses were used to test for demographic events and to place them in a temporal framework. Geographical differences in Drosophila-parasitoid interactions were studied in host-acceptance, host-suitability, and host-choice experiments. All four species showed species-specific phylogeographic patterns. A general trend of the haplotype diversity increasing towards the south was observed. D. albomicans showed very high COI haplotype diversity, and had the most phylogeographically structured populations, with differentiation into the northern and the southern population-group, divided by the Kerama gap. Differentiation in host suitability was observed only between highly structured populations of D. albomicans, possibly facilitated by restricted gene flow. Differentiation in host-acceptance in D. takahashii, and host-acceptance and host-choice in L. ryukyuensis was found, despite there being no differentiation in these two species according to molecular markers. Host choice assays show that L. ryukyuensis populations that have had more time to coevolve adapt their behavior to exploit the most suitable host - D. albomicans. L. ryukyuensis parasitoids on border ranges may, on the other hand, benefit from broader host-acceptance, that may facilitate adaptation to uncertain and variable environments. All results indicate that Drosophila-parasitoid populations in the Ryukyu archipelago and Taiwan have different evolutionary trajectories, and coevolve in a dynamic, complex, and local-specific way.
- Published
- 2015
17. Global gene expression analysis in liver of obese diabetic db/db mice treated with metformin
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H. Ishikawa, M. Heishi, H. Gomi, M. Kanaoka, J. Ichihara, J. Sakai, M. Taiji, Yasushi Itakura, T. Kimura, R. Teramoto, and K. Hayashi
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Blood Glucose ,Male ,medicine.medical_specialty ,endocrine system diseases ,Ratón ,Endocrinology, Diabetes and Metabolism ,Gene Expression ,Mice, Obese ,Type 2 diabetes ,Models, Biological ,Diabetes Mellitus, Experimental ,Mice ,Internal medicine ,Diabetes mellitus ,Gene expression ,Internal Medicine ,medicine ,Animals ,Hypoglycemic Agents ,Oligonucleotide Array Sequence Analysis ,Dose-Response Relationship, Drug ,biology ,nutritional and metabolic diseases ,medicine.disease ,Obesity ,Metformin ,Mice, Inbred C57BL ,Gene expression profiling ,Endocrinology ,Liver ,Glucose-6-Phosphatase ,biology.protein ,Metabolic Networks and Pathways ,Glucose 6-phosphatase ,medicine.drug - Abstract
Metformin is widely used as a hypoglycaemic reagent for type 2 diabetes. While the reduction of hepatic gluconeogenesis is thought to be a key effect, the detailed molecular mechanism of action of metformin remains to be elucidated. To gain insight into this, we performed a global gene expression profiling study.We performed DNA microarray analysis to study global gene expression in the livers of obese diabetic db/db mice 2 h after a single administration of metformin (400 mg/kg).This analysis identified 14 genes that showed at least a 1.5-fold difference in expression following metformin treatment, including a reduction of glucose-6-phosphatase gene expression. The mRNA levels of glucose-6-phosphatase showed one of the best correlations with blood glucose levels among 12,000 genes. Enzymatic activity of glucose-6-phosphatase was also reduced in metformin-treated liver. Moreover, intensive analysis of the expression profile revealed that metformin effected significant alterations in gene expression across at least ten metabolic pathways, including those involved in glycolysis-gluconeogenesis, fatty acid metabolism and amino acid metabolism.These results suggest that reduction of glucose-6-phosphatase activity, as well as suppression of mRNA expression levels of this gene, in liver is of prime importance for controlling blood glucose levels in vivo, at least at early time points after metformin treatment. Our results also suggest that metformin not only affects expression of specific genes, but also alters the expression level of multiple genes linked to the metabolic pathways involved in glucose and lipid metabolism in the liver.
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- 2006
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18. Association of tissue-specific differentially methylated regions (TDMs) with differential gene expression
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Fei Song, Joseph F. Smith, Makoto T. Kimura, Tomoki Matsuyama, Hiroki Nagase, Arlene D. Morrow, and William A. Held
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Male ,Genetics ,Mice, Inbred BALB C ,Genome ,Multidisciplinary ,Reverse Transcriptase Polymerase Chain Reaction ,Restriction landmark genomic scanning ,Gene Expression ,Methylation ,Biological Sciences ,DNA Methylation ,Biology ,Molecular biology ,Bisulfite ,Mice ,Differentially methylated regions ,CpG site ,DNA methylation ,Gene expression ,Animals ,CpG Islands ,Promoter Regions, Genetic ,Gene - Abstract
Early studies proposed that DNA methylation could have a role in regulating gene expression during development [Riggs, A.D. (1975) Cytogenet. Cell Genet. 14, 9–25]. However, some studies of DNA methylation in known tissue-specific genes during development do not support a major role for DNA methylation. In the results presented here, tissue-specific differentially methylated regions (TDMs) were first identified, and then expression of genes associated with these regions correlated with methylation status. Restriction landmark genomic scanning (RLGS) was used in conjunction with virtual RLGS to identify 150 TDMs [Matsuyama, T., Kimura, M.T., Koike, K., Abe, T., Nakao, T., Asami, T., Ebisuzaki, T., Held, W.A., Yoshida, S. & Nagase, H. (2003) Nucleic Acids Res. 31, 4490–4496]. Analysis of 14 TDMs by methylation-specific PCR and by bisulfite genomic sequencing confirms that the regions identified by RLGS are differentially methylated in a tissue-specific manner. The results indicate that 5% or more of the CpG islands are TDMs, disputing the general notion that all CpG islands are unmethylated. Some of the TDMs are within 5′ promoter CpG islands of genes, which exhibit a tissue-specific expression pattern that is consistent with methylation status and a role in tissue differentiation.
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- 2005
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19. Heat-shock-responsive genes are not involved in the adult diapause of Drosophila triauraria
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Masahito T. Kimura and Shin G. Goto
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DNA, Complementary ,Hot Temperature ,media_common.quotation_subject ,Molecular Sequence Data ,Insect ,Diapause ,Biology ,Genetics ,Transcriptional regulation ,Animals ,Drosophila Proteins ,Amino Acid Sequence ,HSP90 Heat-Shock Proteins ,Gene ,Heat-Shock Proteins ,media_common ,Drosophila triauraria ,Sequence Homology, Amino Acid ,Gene Expression Regulation, Developmental ,General Medicine ,Sequence Analysis, DNA ,ノハラカオジロショウジョウバエ ,Hsp70 ,休眠 ,Dormancy ,Drosophila ,Heat-shock-responsive genes ,Sequence Alignment ,熱ショック応答遺伝子 ,Function (biology) - Abstract
Although the molecular regulation of diapause remains largely unknown, there is an accumulation of data suggesting the involvement of heat-shock proteins in the expression of diapause or dormancy. However, Goto et al. [J. Insect Physiol. 44 (1998) 1009] reported that Drosophila triauraria does not express Hsp70 transcripts at normal temperatures, regardless of the diapause state. Here, we investigated the transcriptional regulation of other heat-shock-responsive genes (Hsp23, Hsp26, Hsp83 and Hsrw) in D. triauraria with relation to diapause. The results revealed that these genes are not regulated as a function of diapause, suggesting that they are not involved in the expression of diapause in this species.
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- 2004
20. Vulnerability of the thalamic somatosensory pathway after prolonged global hypoxic–ischemic injury
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Daniel F. Hanley, Jitendran Muthuswamy, Ming Chieh Ding, Nitish V. Thakor, T. Kimura, and Romergryko G. Geocadin
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Cell Survival ,Thalamus ,Action Potentials ,Stimulus (physiology) ,Somatosensory system ,Inhibitory postsynaptic potential ,Synaptic Transmission ,Biological Clocks ,Interneurons ,Evoked Potentials, Somatosensory ,Neural Pathways ,Reaction Time ,Animals ,Medicine ,Evoked potential ,Neurons ,Asphyxia ,Ventral Thalamic Nuclei ,business.industry ,General Neuroscience ,Electroencephalography ,Neural Inhibition ,Somatosensory Cortex ,Rats ,Disease Models, Animal ,Electrophysiology ,Somatosensory evoked potential ,Hypoxia-Ischemia, Brain ,Nerve Degeneration ,Heart Arrest, Induced ,Nerve Net ,medicine.symptom ,business ,Neuroscience - Abstract
The aim of this study was to test the hypothesis that under prolonged global ischemic injury, the somatosensory thalamus and the cortex would manifest differential susceptibility leading to varying degrees of thalamo-cortical dissociation. The thalamic electrical responses displayed increasing suppression with longer durations of ischemia leading to a significant thalamo-cortical electrical dissociation. The data also point to a selective vulnerability of the network oscillations involving the thalamic relay and reticular thalamic neurons. An adult rat model of asphyxial cardiac arrest involving three cohorts with 3 min (G1, n=5), 5 min (G2, n=5) and 7 min (G3, n=5) of asphyxia respectively was used. The cortical evoked response, as quantified by the peak amplitude at 20 ms in the cortical evoked potential, recovers to more than 60% of baseline in all the cases. The multi-unit responses to the somatosensory stimuli recorded from the thalamic ventral posterior lateral (VPL) nuclei consists typically of three components: (1). the ON response (
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- 2002
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21. Genetic analyses of resistance against Leptopilina victoriae in Drosophila bipectinata
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Tetsuo I. Kohyama, Awit Suwito, Masahito T. Kimura, and Tomohiro Takigahira
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Male ,Population ,Genes, Insect ,Plant Science ,Biology ,Plant disease resistance ,Parasitoid ,symbols.namesake ,Genetics ,Animals ,Amplified Fragment Length Polymorphism Analysis ,education ,Drosophila ,Gene ,Crosses, Genetic ,Disease Resistance ,education.field_of_study ,Autosome ,General Medicine ,biology.organism_classification ,Hymenoptera ,Genetic Loci ,Insect Science ,Mendelian inheritance ,symbols ,Animal Science and Zoology ,Amplified fragment length polymorphism ,Female - Abstract
Drosophila bipectinata from Iriomote-jima (IR) is susceptible to the endoparasitoid Leptopilina victoriae from Kota Kinabalu (L. victoriae KK), but D. bipectinata from Kota Kinabalu (KK) and Bogor (BG) is resistant. The cross experiments between the resistant (KK) and susceptible (IR) populations of D. bipectinata suggested that the resistance to this parasitoid is a dominant trait and controlled by a single locus or few linked loci on an autosome. In the AFLP analysis using the IR, KK and BG populations of D. bipectinata and the resistant and susceptible populations derived from a mixed population of these three geographic populations, a DNA fragment almost specific to susceptible flies was detected. It also revealed that genes from the IR population were more frequently maintained in the mixed population compared with those from the KK and BG populations, suggesting that at least a number of genes from the IR population are more advantageous under the laboratory conditions. This explains our previous results that the resistance was lowered in the mixed population although the resistance itself is suggested to incur only low costs; i.e., the resistance gene(s) from the KK and BG populations would have been linked with some genes that are disadvantageous under the laboratory conditions.
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- 2014
22. What determines host acceptance and suitability in tropical Asian Drosophila parasitoids?
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Awit Suwito and Masahito T. Kimura
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food.ingredient ,Oviposition ,Wasps ,Parasitism ,Leptopilina ,Drosophila melanogaster species group ,Parasitoid ,Host-Parasite Interactions ,food ,parasitic diseases ,Animals ,Ecology, Evolution, Behavior and Systematics ,Coevolution ,Asobara ,Larva ,Ecology ,biology ,fungi ,biology.organism_classification ,Indonesia ,Insect Science ,Taxonomy (biology) ,Drosophila ,Female - Abstract
For successful parasitism, parasitoid females must oviposit and the progeny must develop in individual hosts. Here, we investigated the determinants of host acceptance for oviposition and host suitability for larval development of Drosophila parasitoids from Bogor and Kota Kinabalu (≍1,800 km northeast of Bogor), Indonesia, in tropical Asia. Asobara pleuralis (Ashmead) from both localities oviposited frequently (60%) in all of the drosophilid species tested, except the strain from Kota Kinabalu oviposited rarely (10%) in Drosophila eugracilis BockWheeler. Leptopilina victoriae Nordlander from both localities only oviposited frequently (77%) in species from the Drosophila melanogaster species group except D. eugracilis (3.7%), whereas Leptopilina pacifica NovkovićKimura from Bogor oviposited frequently (85%) only in species from the Drosophila immigrans species group. Thus, host acceptance appeared to be affected by host taxonomy, at least in Leptopilina species. Host suitability varied considerably, even among closely related drosophilid species, which suggests that the host suitability is at least in part independent of host taxonomy and that it has been determined via parasitoid-host coevolutionary interactions (i.e., arms race). Host acceptance did not always coincide with host suitability, i.e., parasitoids sometimes oviposited in unsuitable host species. Geographic origin strongly affected the host acceptance and suitability in the A. pleuralis-D. eugracilis parasitoid-host pair, whereas it only weakly affected the acceptability and suitability in other parasitoid-host combinations.
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- 2014
23. Sexual isolation and cuticular hydrocarbons in Drosophila elegans
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Chihiro Katagiri, Kaori Ishii, Yoshiyuki Hirai, and Masahito T. Kimura
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Male ,Chromatography, Gas ,animal structures ,genetic structures ,Offspring ,Cuticle ,media_common.quotation_subject ,Zoology ,Drosophila elegans ,Courtship ,Sexual Behavior, Animal ,Species Specificity ,Inbred strain ,Genetics ,Animals ,Sex Attractants ,Mating ,Drosophila ,Crosses, Genetic ,reproductive and urinary physiology ,Genetics (clinical) ,media_common ,Sex Characteristics ,biology ,Ecology ,fungi ,biology.organism_classification ,Hydrocarbons ,Male courtship behaviour ,Female ,Cues ,psychological phenomena and processes - Abstract
In Drosophila elegans, partial sexual isolation has developed between the brown and black morphs, which are distributed allopatrically. The present study aims to understand how they discriminate between potential mates. Mating experiments show that the females of the two morphs differ in sexual signal(s) and the males discriminate using these differences. Body colouration is not used as a sexual cue in this species. Between the females of the two morphs, a large difference was observed in the percentages of 7-pentacosene and 9-pentacosene on the cuticle. Genetical analysis using recombinant inbred lines supported the possibility that the concentration of these pentacosenes plays a role in mate discrimination of these two morphs. However, males did not respond to killed females at all, suggesting that cuticular hydrocarbons of females are not the only cue for the induction of male courtship behaviour. It may be that unknown signals or substances are essential to induce male courtship and pentacosenes modulate the attractiveness of females, positively in the black morph and negatively in the brown morph. Drosophila elegans F1 offspring had intermediate characteristics in mate discrimination and hydrocarbon composition between the parental brown and black morph strains. The number of loci responsible for the differences in the concentration of pentacosenes and the male and female components in the mate recognition between these two morphs is suggested to be more than one.
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- 2001
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24. Phylogenetic Utility of Mitochondrial COI and Nuclear Gpdh Genes in Drosophila
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Shin G. Goto and Masahito T. Kimura
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Mitochondrial COI ,Glycerolphosphate Dehydrogenase ,macromolecular substances ,DNA, Mitochondrial ,Drosophila melanogaster species group ,Electron Transport Complex IV ,Evolution, Molecular ,Monophyly ,Phylogenetics ,Genetic variation ,parasitic diseases ,Genetics ,Melanogaster ,Animals ,Drosophila (subgenus) ,Molecular Biology ,Gene ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,DNA Primers ,Cell Nucleus ,biology ,Phylogenetic tree ,Base Sequence ,fungi ,Genetic Variation ,biology.organism_classification ,ミトコンドリア ,Mitochondria ,Drosophila melanogaster ,ショウジョウバエ ,Drosophila - Abstract
Phylogenetic utility of the mitochondrial COI (cytochrome oxidase subunit I) and nuclear Gpdh (glycerol-3-phosphate dehydrogenase) genes was studied in the Drosophila melanogaster species group. The rate of substitution was higher in the COI gene than in the Gpdh gene. In addition, multiple substitutions, not only for transitional but also for transversional substitutions, occurred faster in the COI gene. None of the trees obtained using the COI gene supported the well-established monophyly of the ananassae subgroup. In addition, the incongruence length difference test, Templeton test, and partitioned Bremer support revealed that the trees based on the COI data are considerably different from those based on the Gpdh and the combined data set. Thus, the COI gene did not show good phylogenetic performance in the melanogaster group. The present analyses based on the Gpdh gene and the combined data set revealed that the ananassae subgroup branched off first in the melanogaster group followed by the montium subgroup and further by the melanogaster subgroup in contrast to the most recent phylogenetic hypothesis based on Amy multigenes.
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- 2001
25. A novel quantitative EEG injury measure of global cerebral ischemia
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Daniel F. Hanley, R. Ghodadra, T. Kimura, H. Lei, Nitish V. Thakor, Romergryko G. Geocadin, and David L. Sherman
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Male ,medicine.medical_specialty ,Pathology ,Models, Neurological ,Ischemia ,Electroencephalography ,Brain Ischemia ,Quantitative eeg ,Central nervous system disease ,Physiology (medical) ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Analysis method ,Asphyxia ,medicine.diagnostic_test ,Vascular disease ,business.industry ,Brain ,Prognosis ,medicine.disease ,Sensory Systems ,Rats ,Disease Models, Animal ,Cepstral distance ,Neurology ,Cardiology ,Neurology (clinical) ,medicine.symptom ,business - Abstract
To develop a novel quantitative EEG (qEEG) based analysis method, cepstral distance (CD) and compare it to spectral distance (SD) in detecting EEG changes related to global ischemia in rats.Adult Wistar rats were subjected to asphyxic-cardiac arrest for sham, 1, 3, 5 and 7 min (n=5 per group). The EEG signal was processed and fitted into an autoregressive (AR) model. A pre-injury baseline EEG was compared to selected data segments during asphyxia and recovery. The dissimilarities in the EEG segments were measured using CD and SD. A segment measured was considered abnormal when it exceeded 30% of baseline and its duration was used as the index of injury. A comprehensive Neurodeficit Score (NDS) at 24 h was used to assess outcome and was correlated with CD and SD measures.A higher correlation was found with CD and asphyxia time (r=0.81, P0.001) compared to SD and asphyxia time (r=0.69, P0.001). Correlation with cardiac arrest time (MAP10 mmHg) showed that CD was superior (r=0.71, P0.001) to SD (r=0.52, P=0.002). CD obtained during global ischemia and 90 min into recovery correlated significantly with NDS at 24 h after injury (Spearman coefficient=-0.83, P0.005), and was more robust than the traditional SD (Spearman coefficient=-0.63, P0.005).The novel qEEG-based injury index from CD was superior to SD in quantifying early cerebral dysfunction after cardiac arrest and in providing neurological prognosis at 24 h after global ischemia in adult rats. Studying early qEEG changes after asphyxic-cardiac arrest may provide new insights into the injury and recovery process, and present opportunities for therapy.
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- 2000
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26. Expanded polyglutamine stretches interact with TAFII130, interfering with CREB-dependent transcription
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Isao Hozumi, Ichiro Kanazawa, Yasuteru Sano, Mitsunori Yamada, Takayoshi Shimohata, Yasuyuki Aoyagi, Osamu Onodera, Kumi Sakoe, Toshiya Sato, Hiroshi Ishiguro, Naoko Tanese, Chiharu Uchida, Takeshi Ikeuchi, Kenkichi Nozaki, Irwin Davidson, Reiji Koide, Mutsuo Oyake, Masatoyo Nishizawa, Takayuki Ooshima, Toshihiro Nakajima, Yoshihisa Takiyama, Shoji Tsuji, Toshiharu Nagatsu, Satoshi Naruse, Hitoshi Takahashi, Jun Goto, T. Kimura, and Aki Sato
- Subjects
Transcription, Genetic ,Transcription (biology) ,Cloning, Molecular ,Cyclic AMP Response Element-Binding Protein ,Aged, 80 and over ,Genetics ,Cell Death ,biology ,Neurodegeneration ,Brain ,Neurodegenerative Diseases ,Middle Aged ,Cell biology ,DNA-Binding Proteins ,COS Cells ,Electrophoresis, Polyacrylamide Gel ,Female ,Cell Nucleolus ,Plasmids ,Protein Binding ,Transcriptional Activation ,Programmed cell death ,Recombinant Fusion Proteins ,Blotting, Western ,Green Fluorescent Proteins ,Molecular Sequence Data ,Globus Pallidus ,Transfection ,CREB ,Cell Line ,Two-Hybrid System Techniques ,Coactivator ,medicine ,Animals ,Humans ,Aged ,Cell Nucleus ,TATA-Binding Protein Associated Factors ,beta-Galactosidase ,medicine.disease ,Element binding protein ,Precipitin Tests ,Luminescent Proteins ,Dentate Gyrus ,biology.protein ,Transcription Factor TFIID ,Atrophy ,Peptides ,Trinucleotide Repeat Expansion ,Transcription Factors - Abstract
At least eight inherited neurodegenerative diseases are caused by expanded CAG repeats encoding polyglutamine (polyQ) stretches. Although cytotoxicities of expanded polyQ stretches are implicated, the molecular mechanisms of neurodegeneration remain unclear. We found that expanded polyQ stretches preferentially bind to TAFII130, a coactivator involved in cAMP-responsive element binding protein (CREB)-dependent transcriptional activation, and strongly suppress CREB-dependent transcriptional activation. The suppression of CREB-dependent transcription and the cell death induced by polyQ stretches were restored by the co-expression of TAFII130. Our results indicate that interference of transcription by the binding of TAFII130 with expanded polyQ stretches is involved in the pathogenetic mechanisms underlying neurodegeneration.
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- 2000
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27. Mutations in the Activation Loop Tyrosines of Protein Tyrosine Kinase Syk Abrogate Intracellular Signaling But Not Kinase Activity
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J, Zhang, T, Kimura, and R P, Siraganian
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Enzyme Precursors ,Binding Sites ,Receptors, IgE ,Immunology ,Intracellular Signaling Peptides and Proteins ,Protein-Tyrosine Kinases ,Cell Degranulation ,Rats ,Mutation ,Animals ,Syk Kinase ,Immunology and Allergy ,Mast Cells ,Phosphorylation ,Signal Transduction - Abstract
The protein tyrosine kinase Syk plays a pivotal role in mediating the high-affinity IgE receptor (FcεRI)-induced degranulation of mast cells. To examine the mechanism of Syk regulation, the two tyrosine residues at 519 and 520 in the putative activation loop of rat Syk were mutated to phenylalanine either singly or in combination. The various mutants were expressed in a Syk-negative variant of the RBL-2H3 (rat basophilic leukemia 2H3) mast cell line. In these transfected cell lines, mutant Syk did show increased tyrosine phosphorylation in vivo and increased enzymatic activity in vitro after FcεRI aggregation. There were conformational changes detected by an Ab when the wild-type and mutant Syk were either tyrosine phosphorylated or bound to tyrosine-phosphorylated immunoreceptor tyrosine-based activation motif peptides. However, these mutant Syk were incapable of transducing FcεRI signaling. In cells in which the expression level of mutant Syk was similar to that of the wild-type Syk, FcεRI cross-linking induced no increase in cellular protein tyrosine phosphorylation, no increase in tyrosine phosphorylation of phospholipase C-γ2 and mitogen-activated protein kinase, and no histamine release. Overexpression of Y519F or Y520F Syk mutants partially reconstituted the signaling pathways. These results indicate that these tyrosines in the putative activation loop are not essential for the enzymatic activity of Syk or for the conformational changes induced by binding of tyrosine-phosphorylated immunoreceptor tyrosine-based activation motif peptides. However, these tyrosines are necessary for Syk-mediated propagation of FcεRI signaling.
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- 1998
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28. Pharmacokinetics of [125I]-recombinant human interleukin-11
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T. Watanabe, M. Tateishi, S. Higuchi, K. Aoyama, Y. Takariki, T. Uchida, T. Usui, M. Hirose, T. Kimura, K. Mori, and N. Asahara
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medicine.medical_specialty ,Amniotic fluid ,Metabolic Clearance Rate ,Injections, Subcutaneous ,Placenta ,Uterus ,Ovary ,Biology ,Iodine Radioisotopes ,Rats, Sprague-Dawley ,Excretion ,Pharmacokinetics ,Pregnancy ,Internal medicine ,Lactation ,medicine ,Animals ,Humans ,Tissue Distribution ,Pharmacology (medical) ,Maternal-Fetal Exchange ,Pharmacology ,Fetus ,Interleukin-11 ,Recombinant Proteins ,Rats ,medicine.anatomical_structure ,Endocrinology ,Animals, Newborn ,Female - Abstract
Placental transfer and excretion into milk of [125I]-rhIL-11 (recombinant human interleukin-11) after subcutaneous administration in female rats were investigated. After administration of [125I]-rhIL-11 to rats on the 14th day of gestation, radioactivity in the kidney was the highest among excised tissues, being 3 times higher than that in the plasma at 1.5 h. Radioactivity in other tissues, including the mammary gland, ovary, uterus, placenta and amniotic fluid, was lower than that in the plasma. Although radioactivity in fetuses was detected 6 h after administration, the level was only 2% of the plasma concentration in dams, and the radioactivity was not found in fetal-derived TCA precipitates. These results indicate that rhIL-11 does not readily pass through the placenta into the fetus. After subcutaneous administration of [125I]-rhIL-11 to lactating rats 14 days after delivery, radioactivity in milk was 1.1-1.6 times that in the plasma of dams. Radioactivity in clotted milk in the stomachs of suckling infants was almost equal to that in the dam's milk; however, only a small amount of radioactivity was detected in infant kidneys.
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- 1998
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29. How Drosophila species acquire cold tolerance . Qualitative changes of phospholipids
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Chihiro Katagiri, Takashi Ohtsu, and Masahito T. Kimura
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Male ,Hot Temperature ,Acclimatization ,Climate ,Oviposition ,Phospholipid ,Biology ,Biochemistry ,chemistry.chemical_compound ,Japan ,Species Specificity ,Membrane fluidity ,Animals ,Phospholipids ,Unsaturated fatty acid ,chemistry.chemical_classification ,Phosphatidylethanolamine ,Fatty acid ,Homeoviscous adaptation ,Cold Temperature ,Membrane ,chemistry ,Fatty Acids, Unsaturated ,Drosophila ,Female ,Polyunsaturated fatty acid - Abstract
Phospholipids of many cold-tolerant organisms have been reported to contain more unsaturated fatty acids than cold-susceptible organisms, a phenomenon known to maintain membrane fluidity at low temperature. However, we have obtained results to the contrary through a comparison of the membrane phospholipids of six temperate and subtropical species belonging to the Drosophila melanogaster species group. With enhancement of cold tolerance, the percentages of monoenoic acids increased but the percentages of dienoic acids decreased, that is, the number of double bonds in the phospholipid decreased without a marked variation in the percentages of unsaturated fatty acids. Concomitantly, the percentage of fatty acids containing 16 carbon atoms increased, while that of fatty acids with 18 carbon atoms decreased. Since phosphatidylethanolamine is a dominant phospholipid in Drosophila, these changes probably contribute to keeping the homeoviscosity of the cellular membranes in a manner different to that in phosphatidylcholine-rich membranes, thereby increasing cold tolerance.
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- 1998
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30. Increased natural killer resistance to cyclosporine A by continuous doses of dexamethasone in rats
- Author
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H. Takakuwa, Y. Sakamoto, F. Yoshida, J.‐I. Hosokawa, E. Kamio, K. Tagami, M. Sakurai, T. Kimura, and K. Nakagawa
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Cytotoxicity, Immunologic ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Immunology ,Dose-Response Relationship, Immunologic ,Dexamethasone ,Drug Administration Schedule ,Immune system ,Internal medicine ,medicine ,Animals ,Immunology and Allergy ,Glucocorticoids ,Saline ,business.industry ,Nk activity ,Healthy subjects ,Rats, Inbred F344 ,Rats ,Killer Cells, Natural ,Endocrinology ,Cyclosporine ,business ,Immunosuppressive Agents ,hormones, hormone substitutes, and hormone antagonists ,Research Article ,medicine.drug - Abstract
There is a controversy on the effects of physiological levels of glucocorticoids on natural killer (NK) cytotoxity. Therefore, the effects of exogenously administered dexamethasone on NK cytotoxity in 8-week-old male, Fischer 344 rats were studied. We suppose that the reason for the controversy is insufficient sensitivity of the ordinal radioactive chromium-release assay for normal healthy subjects or animals. Therefore, we developed a new index, a resistance to artificial immunosuppressor, cyclosporine A (CsA) using rat NK activity as an indicator, and named this index, increased resistance to immunosuppressor (IRIS). After some basic, characterizing studies, authors confirmed the fact that continuous doses of dexamethasone (DEX) attenuated NK suppression of CsA. In protocol 4, 18 rats were randomly divided into three groups: the first (DEX + CsA) was injected for 5 days with 0.1 mg DEX/kg/day and a single dose of CsA on the final day, intraperitoneally; the second (SAL + CsA) was treated with an equal volume of saline and CsA; the third (DEX + SAL) was treated with DEX but not CsA. The IRIS in NK activity was increased significantly (P < 0.01) with 5 days injection of DEX. These results demonstrated that physiological, and continuous dosage of glucocorticoids stimulated IRIS in NK activity in rats, and this suggests that appropriate stimuli through the hypothalamic-adrenal axis might be acting, at least, as a defence against immune collapses or dysfunctions.
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- 1997
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31. <scp>l</scp>-Citrulline conversion to<scp>l</scp>-arginine in sphenopalatine ganglia and cerebral perivascular nerves in the pig
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T. Kimura, J. G. Yu, Takaaki Ishine, Tony J.-F. Lee, and William E. O'Brien
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Cerebral veins ,Pathology ,medicine.medical_specialty ,Swine ,Physiology ,Argininosuccinate synthase ,Cerebral arteries ,Argininosuccinate Synthase ,Arginine ,chemistry.chemical_compound ,Nerve Fibers ,Physiology (medical) ,medicine ,Citrulline ,Animals ,Dihydrolipoamide Dehydrogenase ,biology ,Pia mater ,Ganglia, Parasympathetic ,Anatomy ,Cerebral Arteries ,Argininosuccinate Lyase ,Cerebral Veins ,Argininosuccinate lyase ,Electric Stimulation ,NG-Nitroarginine Methyl Ester ,medicine.anatomical_structure ,chemistry ,Circulatory system ,cardiovascular system ,biology.protein ,Pia Mater ,Nitric Oxide Synthase ,Cardiology and Cardiovascular Medicine ,Blood vessel - Abstract
The presence of nitric oxide synthase (NOS), argininosuccinate synthetase (ASS), and argininosuccinate lyase (ASL) and their coexistence with NADPH-diaphorase (NADPHd), a marker for NOS, in the porcine sphenopalatine ganglia (SPG), pial veins, and the anterior cerebral arteries was examined using immunohistochemical and histochemical staining techniques. NOS-immunoreactive (I), ASS-I, and ASL-I fibers were found in pial veins and the anterior cerebral arteries. NOS, ASS, and ASL immunoreactivities were also found in neuronal cell bodies in the SPG. Almost all neuronal cell bodies in the SPG and nerve fibers in pial veins and the anterior cerebral arteries that were reactive to ASS, ASL, and NOS were also stained positively with NADPHd, suggesting that ASS, ASL, and NOS were colocalized in the same neurons in the SPG and perivascular nerves. With the use of in vitro tissue bath techniques,l-citrulline but notd-citrulline reversed inhibition of neurogenic vasodilation in isolated porcine pial veins produced by NOS inhibitors such as NG-nitro-l-arginine methyl ester. In the presence of l-aspartate,l-arginine was synthesized froml-citrulline in homogenates of SPG and endothelium-denuded cerebral arteries and pial veins. These results provide evidence indicating that perivascular nerves in pial veins like cerebral arteries can convertl-citrulline tol-arginine for synthesizing nitric oxide. The conversion is most likely via an argininosuccinate pathway.
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- 1997
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32. Induction of intestinal lesions in nu/nu mice induced by transfer of lymphocytes from syngeneic mice infected with murine retrovirus
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T Mizuochi, T Narita, K Ohtsuka, S Inada, K. Suzuki, Michio Fujiwara, M. Makino, Ryogo Yui, Y Okada, T Kimura, and Hitoshi Asakura
- Subjects
Pathology ,medicine.medical_specialty ,Lymphocyte ,Immunology ,Mice, Nude ,Autoimmunity ,Spleen ,Biology ,Virus ,Mice ,Murine leukemia virus ,medicine ,Animals ,Germ-Free Life ,Lymphocytes ,Colitis ,Immunodeficiency ,Leukemia, Experimental ,Gastroenterology ,Hyperplasia ,medicine.disease ,biology.organism_classification ,Intestines ,Leukemia Virus, Murine ,Mice, Inbred C57BL ,Disease Models, Animal ,Tumor Virus Infections ,Mononuclear cell infiltration ,Sjogren's Syndrome ,medicine.anatomical_structure ,Lymphocyte Transfusion ,Female ,Retroviridae Infections - Abstract
Background—Murine leukemia virus, LP-BM5, induces severe immunodeficiency with abnormal lymphoproliferation in susceptible C57BL/6 mice. In a previous study, it was shown that a Sjögren’s syndrome-like systemic exocrinopathy is induced in the virus infected mice.Aims—To examine lymphocyte functions of the virus infected mice.Methods—Four-week old mice were inoculated with the virus and their spleen cells were transferred into syngeneic nu/nu mice. Their organs were examined by light and electron microscopy. Phenotypes of the colon infiltrating cells were examined by flow cytometry.Results—All nu/nu recipients had died by six weeks after cell transfer, showing runting disease like cachexia with diarrhoea and anal bleeding. Histopathological examination revealed that systemic exocrinopathy was adoptively transferable and that the colon became thickened due to mononuclear cell infiltration into the mucosal and submucosal layer with hyperplasia of intestinal epithelial cells. No virus particles were found in the colon. Flow cytometric analyses revealed that most of the infiltrating CD4+ T cells showed CD45RBlow. No intestinal lesions were observed in the virus infected mice nor in nu/nu mice inoculated with normal lymphocytes.Conclusion—Lymphocytes of the virus infected mice induced colitis and hyperplasia of intestinal epithelial cells as well as systemic exocrinopathy in nu/nu mice. Our experimental system may give some insight into intestinal lesions associated with virus infection.
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- 1997
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33. Myocardial necrosis depth prediction during extracellular photosensitization reaction of talaporfin sodium by defined index using fluorescence measurement
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T. Kimura, Keiichi Fukuda, A. Ito, M. Takahashi, Seiji Takatsuki, and Tsunenori Arai
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Necrosis ,Photosensitizing Agents ,Porphyrins ,Chemistry ,medicine.medical_treatment ,Myocardium ,Analytical chemistry ,Photodynamic therapy ,Dermatology ,Fluorescence ,Nuclear magnetic resonance ,Dogs ,Spectrometry, Fluorescence ,Interstitial space ,Photochemotherapy ,In vivo ,medicine ,Extracellular ,Animals ,Surgery ,Photosensitizer ,Irradiation ,medicine.symptom ,Extracellular Space - Abstract
An application of photodynamic therapy for myocardial ablation, which would induce myocardial electrical conduction block, is proposed. For the proposed application, an extracellular photosensitization reaction (PR) is performed while photosensitizer is distributed in myocardial interstitial space by employing a short drug-light interval. Because the myocardial necrosis depth must be accurately controlled to prevent surrounding tissue injury during the myocardial ablation procedure, the necrosis depth during PR needs to be predicted. The purpose of this study is to investigate the availability of predicting PR-induced myocardial necrosis depth (d nec) using a defined fluorescence-fall amount (FA), which is the calculated result of fluorescence intensity decrease from the start of the PR multiplied by irradiation duration and corresponds to photosensitizer consumption amount under an assumption that the photosensitizer consumption rate is faster than the photosensitizer supply rate. The correlation between FA and d nec was experimentally investigated in vivo using an open-chested canine heart model with 2.5 and 5.0 mg/kg of talaporfin sodium at an irradiance of 5–20 W/cm2 for 5–20 s. The fluorescence measurement was performed at a wavelength of 710 nm during the PR to derive FA. One week after the PR, a uniform necrosis depth was measured histopathologically as d mnec. A logarithmic correlation between d mnec and FA was confirmed with R 2 = 0.69–0.80 and a d mnec range of 0.2–7.1 mm. The defined FA might be useful for predicting d nec for the extracellular PR in myocardium when using talaporfin sodium.
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- 2013
34. Venom components of Asobara japonica impair cellular immune responses of host Drosophila melanogaster
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Shunsuke X, Furihata, Hitoshi, Matsumoto, Masahito T, Kimura, and Yoichi, Hayakawa
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Immunity, Cellular ,Drosophila melanogaster ,Hemocytes ,Phagocytosis ,Species Specificity ,Larva ,Oviposition ,Wasps ,Animals ,Female ,Wasp Venoms ,Host-Parasite Interactions ,Immunity, Humoral - Abstract
The endoparasitoid wasp Asobara japonica has highly poisonous venom: the host Drosophila larvae are killed by envenomation at a dose that is naturally injected by the female wasp at parasitism. This insecticidal venom is neutralized, however, because A. japonica introduces lateral oviduct components soon after venom injection at oviposition. Although the venom and lateral oviduct components of this parasitoid have been partially characterized, how the venom components favor successful development of wasp eggs and larvae in the host remains ambiguous. Here, we demonstrated that A. japonica venom did not affect host humoral immune responses, determined as expression of antimicrobial peptide (AMP) genes, but significantly diminished two cellular responses, spreading and phagocytosis, by host hemocytes. Moreover, venom components drastically elevated a serine protease-like activity 4 h after its injection. The lateral oviduct components did not negate the detrimental effects of the venom on host cellular immunities, but significantly reduced the venom-induced elevation of protease activity. Both active factors in venom and lateral oviduct components were roughly characterized as heat-labile substances with a molecular mass of at least 10 kDa. Finally, venom of A. japonica, with a wide host range, was found to be much more toxic than that of Asobara rossica, which has a limited host range. These results reveal that A. japonica venom toxicity allows exploitation of a broader range of host insects because it is essential to overcome cellular immune responses of the host for successful parasitism.
- Published
- 2013
35. Monoclonal antibody against lymphocyte function-associated antigen 1 inhibits the formation of primary biliary cirrhosis-like lesions induced by murine graft-versus-host reaction
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T, Kimura, K, Suzuki, S, Inada, A, Hayashi, M, Isobe, Y, Matsuzaki, N, Tanaka, T, Osuga, and M, Fujiwara
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Hepatology ,Liver Cirrhosis, Biliary ,Antibodies, Monoclonal ,Pyruvate Dehydrogenase Complex ,Flow Cytometry ,Intercellular Adhesion Molecule-1 ,Antibodies ,Lymphocyte Function-Associated Antigen-1 ,Mice, Inbred C57BL ,Graft vs Host Reaction ,Mice ,Liver ,Splenomegaly ,Animals - Abstract
Interaction between intercellular adhesion molecule 1 (ICAM-1) and lymphocyte function-associated antigen 1 (LFA-1) might be involved in the pathogenesis of liver diseases. We investigated whether monoclonal antibodies (mAbs) against these two adhesion molecules could inhibit the formation of primary biliary cirrhosis (PBC)-like lesions in an animal model using graft-versus-host reaction (GVHR) with major histocompatibility complex class II disparity. PBC-like hepatic lesions such as cellular infiltration of portal area and nonsupprative destructive cholangitis (NSDC) were generated by injecting spleen T cells of C57BL/6 (B6) mice into (B6. C-H-2bm12 X B6) F1 mice. In the liver of these mice, increased number of LFA-1-positive cells and enhanced expression of ICAM-1 on sinusoidal endothelial cells and bile duct epithelial cells were observed immunohistochemically, when compared with F1 mice without GVHR. Hepatic lesions of these mAb-treated mice were almost completely inhibited in these mice compared with GVHR mice. Furthermore, we studied to determine which anti-LFA-1 mAb or anti-ICAM-1 mAb was essential to inhibit the hepatic lesions. Mice solely treated with anti-LFA-1 mAb showed significant inhibition of hepatic lesions, whereas treatment with anti-ICAM-1 mAb could not inhibit the lesions. Despite the inhibition of hepatic lesions, induction of GVHR and production of antimitochondrial antibodies were not impaired in mAb-treated mice. We conclude that LFA-1 mediates cell infiltration into the liver in this murine model of GVHR and suggest a possible therapeutic role of mAbs to this adhesion molecule in selective autoimmune liver diseases.
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- 1996
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36. Hyperbaric oxygenation prevents delayed neuronal death following transient ischaemia in the gerbil hippocampus
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H. Harai, J. Takamatsu, Shingo Baba, Toru Iwaki, T. Kimura, A. Kondo, and H. Koga
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Male ,medicine.medical_specialty ,Histology ,Ischemia ,Hippocampus ,Hippocampal formation ,Gerbil ,Neuroprotection ,Functional Laterality ,Pathology and Forensic Medicine ,Physiology (medical) ,medicine ,Animals ,Oxygen toxicity ,Heat-Shock Proteins ,Neurons ,Hyperbaric Oxygenation ,Cell Death ,business.industry ,Human brain ,medicine.disease ,Immunohistochemistry ,Surgery ,Microscopy, Electron ,medicine.anatomical_structure ,nervous system ,Neurology ,Ischemic Attack, Transient ,Anesthesia ,Neurology (clinical) ,Neuron ,Gerbillinae ,business ,Cell Nucleolus - Abstract
The mechanism of the neuroprotective effect of hyperbaric oxygenation remains unclear although its clinical benefits have been well recognized for human ischaemic neuronal disease. The preventive effect of hyperbaric oxygenation against delayed neuronal death was investigated in the gerbil following transient forebrain ischaemia. Delayed neuronal death in the gerbil was produced by clips on both the common carotid arteries (10 min). Morphological examination was carried out after several protocols of hyperbaric oxygenation, modified from the protocols for human ischaemic neuronal disease. Neurons in the hippocampal CA1 were well preserved in the gerbils treated with hyperbaric oxygenation, more so than in the gerbils with no hyperbaric oxygenation. Moreover, more neurons were preserved in the CA1 treated with hyperbaric oxygenation within 6 h of the ischaemia, than when the hyperbaric oxygenation was started 24 h after the ischaemia. The induction of heat shock proteins (HSP72 and HSP27) became weaker in the gerbils with hyperbaric oxygenation than in those without hyperbaric oxygenation, as seen immunohistochemically. We also observed an increase in dense bodies, that were shown to be lysosomes and myelinoid structures in the cytoplasm of the neurons ultrastructurally, in the hippocampus with hyperbaric oxygenation. However, no oxygen toxicity to the neurons was detected, up to at least two atmospheres absolute. This experimental system was useful to investigate the preventive mechanism of hyperbaric oxygenation against delayed neuronal death in the gerbil, and to determine the clinical indications and the most effective protocol for hyperbaric oxygenation for ischaemic neuronal damage in the human brain.
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- 1996
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37. Novel 2-Amino-1,4-dihydropyridine Calcium Antagonists. II. Synthesis and Antihypertensive Effects of 2-Amino-1,4-dihydropyridine Derivatives Having N,N-Dialkylaminoalkoxycarbonyl Groups at 3- and/or 5-Position
- Author
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T, Kobayashi, T, Inoue, S, Nishino, Y, Fujihara, K, Oizumi, and T, Kimura
- Subjects
Male ,Dihydropyridines ,Structure-Activity Relationship ,Magnetic Resonance Spectroscopy ,Rats, Inbred SHR ,Hypertension ,Drug Discovery ,Animals ,General Chemistry ,General Medicine ,Calcium Channel Blockers ,Antihypertensive Agents ,Rats - Abstract
Novel 2-amino-1,4-dihydropyridine derivatives I, which contain N,N,-dialkylaminoalkoxycarbonyl groups at the 3- and/or 5-position, were synthesized and their antihypertensive effects were evaluated in spontaneously hypertensive rats. Remarkably prolonged duration of antihypertensive action was observed when a tertiary amino group was introduced into either the 3- and/or 5-ester side-chain of the 1,4-dihydropyridine ring. In particular, the compounds containing cyclic amino moieties at the 3-position showed greater potency than those with acyclic amino moieties. Chemical modification studies indicated that the two ester side-chains of 1,4-dihydropyridine at the 3- and 5-position might function in a different manner in relation to the antihypertensive activities. 3-(1-Benzhydrylazetidinited potent and long-lasting antihypertensive effects with gradual onset of action, and is a promising candidate as an antihypertensive drug.
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- 1995
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38. Immunosuppressive effect of prolactin-induced protein
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S, Sugiura, M, Fujimiya, H, Ebise, Y, Miyahira, I, Kato, Y, Sugiura, T, Kimura, M, Uehara, H, Sato, and H, Sugiura
- Subjects
Immunosuppression Therapy ,Keratinocytes ,Male ,Binding Sites ,Oxazolone ,Down-Regulation ,Proteins ,HLA-DR Antigens ,Immunohistochemistry ,Antibodies ,Mice, Inbred C57BL ,Disease Models, Animal ,Mice ,CD4 Antigens ,Dermatitis, Allergic Contact ,Animals - Abstract
Prolactin-induced protein (PIP) has been shown to bind to CD4 and is speculated to block CD4-HLA-DR interaction. However, the immunomodulatory effect of PIP on chronic allergic contact dermatitis (ACD) remains to be elucidated. The aim of this work was to define the role of PIP during the immunoresponse. Using an oxazolone-induced mouse chronic ACD model, expression of PIP was immunohistologically examined. Furthermore, effects of continued exposure of a peptide mimicking the major binding site of PIP (amino acids 106-132) for CD4 was examined in a mouse chronic ACD model. We clarified that keratinocytes and dermal infiltrating cells are positively stained with anti-PIP antibody. The PIP peptide significantly downregulated oxazolone-induced mouse ACD compared to the controls. We also found that inflammation of PIP-non-applied control ear was also suppressed in a synchronized manner in the late phase of the PIP peptide applied mouse. These findings suggest that PIP might have an immunosuppressive effect in mouse chronic ACD.
- Published
- 2012
39. Loss of biological activity of human chorionic gonadotropin (hCG) by the amino acid substitution on the 'CMGCC' region of the α-subunit
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Masami Kusunoki, Naoko Nishikiori, Fumitaka Saji, T. Kikuchi, Kiyoshi Miyai, Tadashi Kimura, Osamu Tanizawa, T. Kimura, Masayasu Koyama, and Chihiro Azuma
- Subjects
Male ,medicine.medical_specialty ,DNA, Complementary ,Molecular Sequence Data ,Mutant ,Gene Expression ,Biology ,Biochemistry ,Protein Structure, Secondary ,Human chorionic gonadotropin ,Immunoenzyme Techniques ,Mice ,Xenopus laevis ,Endocrinology ,Complementary DNA ,Internal medicine ,medicine ,Animals ,Humans ,Point Mutation ,Amino Acid Sequence ,RNA, Messenger ,Site-directed mutagenesis ,Molecular Biology ,Messenger RNA ,Base Sequence ,Leydig cell ,Leydig Cells ,Biological activity ,Molecular biology ,medicine.anatomical_structure ,Glycoprotein Hormones, alpha Subunit ,Mutagenesis, Site-Directed ,Oocytes ,Cysteine - Abstract
In order to study the bioactive sites of the glycoprotein hormones, we have prepared five point mutants on the CMGCC (Cys 28 -Met 29 -Gly 30 -Cys 31 -Cys 32 ) region of the human α-subunit by using site-directed mutagenesis. Each mutant human chorionic gonadotropin (hCG) agr; cDNA and a wild-type hCGβ cDNA were transcribed by T3 RNA polymerase, and the mixture of the hCGα mRNA and hCGβ mRNA was microinjected into Xenopus laevis oocytes. All five mutant hCGs produced in oocyte culture supernatants were detected as immunoreactive forms by enzyme immunoassay. In contrast, four mutants (Cys 28 → Tyr 28 , Gly 30 → Arg 30 , Ala 30 , Asp 30 ) were devoid of biological activity in vitro bioassay using the production of testosterone with mouse Leydig cells. These results indicate that the CMGCC region in the α-subunit, particularly the cysteine residue at position 28 and the glycine residue at position 30, plays an important role in the biosynthesis of glycoprotein hormones.
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- 1994
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40. Carboxyl-terminal parathyroid hormone fragments stimulate osteoclast-like cell formation and osteoclastic activity
- Author
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Hidesuke Kaji, Masaaki Fukase, Toshitsugu Sugimoto, T Kimura, Masanori Kanatani, Akimitsu Miyauchi, Kazuo Chihara, and S Sakakibara
- Subjects
medicine.medical_specialty ,Osteoclasts ,Parathyroid hormone ,Cell Separation ,Biology ,Bone resorption ,Calcium in biology ,Mice ,Endocrinology ,Osteoclast ,Precursor cell ,Internal medicine ,Bone cell ,Cyclic AMP ,medicine ,Animals ,Bone Resorption ,Cellular Senescence ,chemistry.chemical_classification ,Mice, Inbred ICR ,Osteoblasts ,Biological activity ,Intracellular Membranes ,Hematopoietic Stem Cells ,Peptide Fragments ,Rats ,Amino acid ,medicine.anatomical_structure ,chemistry ,Parathyroid Hormone ,Calcium ,Rabbits ,Cell Division - Abstract
The controversy still exists about the biological activity of carboxyl (C)-terminal PTH fragments. The present study was performed to examine the effect of C-terminal PTH fragments on osteoclast-like cell formation and bone-resorbing activity. In contrast to human (h) PTH-(1-34) or hPTH-(1-84), any C-terminal fragments examined [hPTH-(35-84), hPTH-(53-84), and hPTH-(69-84)] did not affect cellular cAMP production and intracellular calcium in osteoblastic UMR-106 cells. Although hPTH-(1-84) caused an increase in cAMP production and intracellular calcium less effectively than hPTH-(1-34) in UMR-106 cells, the former caused a stimulation of osteoclast-like cell formation in osteoblast-containing mouse bone cell cultures more effectively than the latter. All of the C-terminal fragments significantly stimulated osteoclast-like cell formation, and their effectiveness seemed to depend on the amino acid length of the fragments. The conditioned medium from UMR-106 cells pretreated with C-terminal PTH as well as amino-terminal PTH significantly stimulated osteoclast-like cell formation from mouse hemopoietic blast cells supported by granulocyte-macrophage colony-stimulating factor. Moreover, all of the C-terminal fragments stimulated osteoclast-like cell formation from hemopoietic blast cells even in the absence of osteoblasts, and their effectiveness seemed to depend on the length of fragments. As for bone-resorbing activity by mature osteoclasts, all of the C-terminal fragments stimulated bone resorption in osteoblast-containing mouse bone cell cultures, whereas these fragments did not affect the bone-resorbing activity of isolated rabbit osteoclasts. The present study first indicates that C-terminal PTH fragments stimulate osteoclast-like cell formation as well as bone-resorbing activity by mature osteoclasts in the presence of osteoblasts and accelerate osteoclast-like cell formation from hemopoietic blast cells in the absence of osteoblasts.
- Published
- 1994
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41. Response of plasma tissue factor pathway inhibitor to diet-induced hypercholesterolemia in crab-eating monkeys
- Author
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Shin Nakamura, A. Takenaka, Hisao Kato, T. Kimura, S. Miyamoto, Y. Yoshikuni, O. Takenaka, K.-I. Enjyoji, and T. Abumiya
- Subjects
Very low-density lipoprotein ,medicine.medical_specialty ,Serine Proteinase Inhibitors ,Lipoproteins ,Hypercholesterolemia ,Biology ,Cholesterol, Dietary ,chemistry.chemical_compound ,Tissue factor ,Tissue factor pathway inhibitor ,Internal medicine ,Blood plasma ,medicine ,Animals ,Antigens ,Heparin ,Cholesterol ,Macaca fascicularis ,Endocrinology ,chemistry ,Coagulation ,lipids (amino acids, peptides, and proteins) ,Cardiology and Cardiovascular Medicine ,medicine.drug ,Lipoprotein - Abstract
Tissue factor pathway inhibitor (TFPI), a protease inhibitor associated with lipoproteins in plasma and endothelial cells, can inhibit the initial reactions of the tissue factor-mediated coagulation pathway. A positive relationship between TFPI and cholesterol has been demonstrated in human plasma. To investigate this relation in more detail, in the present study we measured TFPI in the plasma of monkeys on a high-cholesterol diet. After diet treatment, cholesterol levels and TFPI activity were increased 3- and 1.5-fold, respectively. Three forms of TFPI, low-density lipoprotein (LDL)/very-low-density lipoprotein (VLDL)-associated TFPI, high-density lipoprotein (HDL)-associated TFPI, and free TFPI, were measured after gel filtration of plasma. In hypercholesterolemic monkeys, levels of TFPI activity and antigen in the LDL/VLDL fraction were increased to about three times those of normal monkeys. Changes in HDL-associated TFPI and free TFPI were not significant compared with the change in LDL/VLDL-associated TFPI. After the monkeys received heparin infusions TFPI was increased about fivefold, but there was no significant difference in these increases between normal and hypercholesterolemic monkeys. The increase in TFPI after heparin infusion is discussed in terms of the relationship between lipoprotein-associated TFPI in plasma and endothelial cell-associated TFPI.
- Published
- 1994
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42. Interactions of ginsenosides with ligand-bindings of GABAA and GABAB receptors
- Author
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Hack-Seang Kim, T. Kimura, I. K. Ho, Ki Wan Oh, P.A. Saunders, and H.M. Rheu
- Subjects
Male ,Baclofen ,Ginsenosides ,Stereochemistry ,Molecular Sequence Data ,Herb-Drug Interactions ,Saponin ,Panax ,Flunitrazepam ,GABAB receptor ,Ligands ,Sulfur Radioisotopes ,Tritium ,Rats, Sprague-Dawley ,Bridged Bicyclo Compounds ,chemistry.chemical_compound ,Animals ,Pharmacology ,chemistry.chemical_classification ,Plants, Medicinal ,Muscimol ,GABAA receptor ,Saponins ,Bridged Bicyclo Compounds, Heterocyclic ,Receptors, GABA-A ,Ligand (biochemistry) ,In vitro ,Rats ,Carbohydrate Sequence ,Receptors, GABA-B ,chemistry ,Ginsenoside - Abstract
1. 1. Total saponin fraction decreased the affinity of specific [ 3 H]muscimol binding without changes in B max . Ginsenoside Rb 1 Rb 2 , Rc, Re, Rf and Rg 1 inhibited the specific [ 3 H]muscimol binding to the high-affinity site. 2. 2. Total saponin fraction increased the affinity of specific [ 3 H]flunitrazepam binding. Ginsenoside Re and Rf enhanced specific [ 3 H]flunitrazepam binding. 3. 3. Total saponin fraction decreased the affinity of specific [ 35 S]TBPS binding without changes in B max . Ginsenosides did not affect specific or non-specific [ 35 S]TBPS binding. 4. 4. Total saponin fraction decreased the affinity of specific [ 3 H]baclofen binding without changes in B max . Ginsenoside Rc inhibited specific [ 3 H]baclofen binding.
- Published
- 1994
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43. Stimulatory Effects of HSR-803 on Ileal Motor Activity
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Y, Iwanaga, N, Suzuki, K, Kato, T, Kimura, K, Morikawa, H, Kato, Y, Ito, and Y, Gomi
- Subjects
Male ,medicine.medical_specialty ,medicine.medical_treatment ,Guinea Pigs ,Myenteric Plexus ,In Vitro Techniques ,Pharmacology ,chemistry.chemical_compound ,Ileum ,Dopamine ,Internal medicine ,Benzyl Compounds ,medicine ,Animals ,Potency ,Receptors, Cholinergic ,Ketamine ,SCH-23390 ,Membranes ,Chemistry ,Dopamine antagonist ,Methamphetamine ,Acetylcholine ,Stimulation, Chemical ,Perfusion ,Quinuclidinyl Benzilate ,Stimulant ,Endocrinology ,Benzamides ,NMDA receptor ,Carbachol ,Peristalsis ,Cholinesterase Inhibitors ,medicine.drug - Abstract
Stimulatory effects of HSR-803 on intestinal motor activity in vitro were studied in guinea pig ileum. HSR-803 (1 x 10(-6)-1 x 10(-4) M) increased the amplitude of longitudinal muscle contractions and increased the frequency of peristalsis in isolated segments of guinea pig ileum. The stimulatory effect in amplitude and not frequency was abolished by 1 x 10(-6) M atropine. In the Magnus method with ileal segments, HSR-803 (1 x 10(-7) - 1 x 10(-4) M) produced contractions concentration-dependently, which were inhibited by atropine (1 x 10(-8) and 3 x 10(-8) M) and 3 x 10(-7) M tetrodotoxin (TTX). In the [3H]-quinuclidinyl benzilate (QNB) binding experiment with ileal smooth muscle, HSR-803 had low affinity for acetylcholine (ACh) receptors (pKi = 4.47 +/- 0.04). In addition, HSR-803 failed to increase the spontaneous release and the electrical stimulation-induced [3H]ACh release in ileal smooth muscle. On the other hand, HSR-803 (1 x 10(-5) M) enhanced contractions induced by ACh, but had no effect on contractions induced by carbachol, which is not hydrolyzed by acetylcholinesterase (AChE). In conclusion, HSR-803 stimulated ileal motor activity. However, HSR-803 had low affinity for ACh receptors and had no influence on ACh release. It is likely that HSR-803 stimulated motor activity mainly due to prevention of ACh hydrolysis.
- Published
- 1993
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44. Hydrogen sulphide protects mouse pancreatic β-cells from cell death induced by oxidative stress, but not by endoplasmic reticulum stress
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S, Taniguchi, L, Kang, T, Kimura, and I, Niki
- Subjects
Caspase 7 ,Male ,Mice, Inbred ICR ,Caspase 3 ,Tunicamycin ,Palmitates ,Apoptosis ,DNA Fragmentation ,Hydrogen Peroxide ,In Vitro Techniques ,Sulfides ,Endoplasmic Reticulum ,Research Papers ,Cell Line ,Mice ,Oxidative Stress ,Stress, Physiological ,Insulin-Secreting Cells ,Animals ,Cytokines ,Thapsigargin ,Hydrogen Sulfide ,Reactive Oxygen Species ,Proto-Oncogene Proteins c-akt - Abstract
Hydrogen sulphide (H₂S), a potentially toxic gas, is also involved in the neuroprotection, neuromodulation, cardioprotection, vasodilatation and the regulation of inflammatory response and insulin secretion. We have recently reported that H₂S suppresses pancreatic β-cell apoptosis induced by long-term exposure to high glucose. Here we examined the protective effects of sodium hydrosulphide (NaHS), an H₂S donor, on various types of β-cell damage.Isolated islets from mice or the mouse insulinoma MIN6 cells were cultured with palmitate, cytokines (a mixture of tumour necrosis factor-α, interferon-γ and interleukin-1β), hydrogen peroxide, thapsigargin or tunicamycin with or without NaHS. We examined DNA fragmentation, caspase-3 and -7 activities and reactive oxygen species (ROS) production in the treated cells thereafter. Apoptotic cell death in isolated islets was also assessed by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) method.NaHS suppressed DNA fragmentation and the activities of caspase-3 and -7 induced by palmitate, the cytokines or hydrogen peroxide. In contrast, NaHS failed to protect islets and MIN6 cells from apoptosis induced by thapsigargin and tunicamycin, both of which cause endoplasmic reticulum stress. NaHS suppressed ROS production induced by cytokines or hydrogen peroxide but it had no effect on ROS production in thapsigargin-treated cells. NaHS increased Akt phosphorylation in MIN6 cells treated with cytokines but not in cells treated with thapsigargin. Treatment with NaHS decreased TUNEL-positive cells in cytokine-exposed islets.H₂S may prevent pancreatic β-cells from cell apoptosis via an anti-oxidative mechanism and the activation of Akt signalling.
- Published
- 2010
45. Autoimmunomodulation
- Author
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J M Stefano, Eric M. Smith, L A Mallozzi, George B. Stefano, J P Finn rd, T Kimura, Michael K. Leung, Thomas K. Hughes, and S Pryor
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Aging ,Immunity, Cellular ,biology ,General Neuroscience ,Vertebrate ,Autoantigens ,General Biochemistry, Genetics and Molecular Biology ,Immune system ,History and Philosophy of Science ,Opioid ,Immunity ,biology.animal ,Age related ,Immunology ,medicine ,Animals ,Humans ,Endorphins ,medicine.drug ,Invertebrate - Published
- 1992
- Full Text
- View/download PDF
46. Photodynamic therapy using pheophorbide-a and Q-switched Nd:YAG Laser on implanted human hepatocellular carcinoma
- Author
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S Ono, K Kajimura, Noriyuki Hamato, Masahiko Sakai, T Kimura, Motoshige Nabeshima, Yukitaka Yamashita, Minoru Okuma, Hitoshi Someda, and Fuminori Moriyasu
- Subjects
Chlorophyll ,Male ,Radiation-Sensitizing Agents ,medicine.medical_specialty ,Pathology ,Necrosis ,medicine.medical_treatment ,Mice, Nude ,Photodynamic therapy ,Mice ,chemistry.chemical_compound ,Liver Neoplasms, Experimental ,Internal medicine ,medicine ,Animals ,Humans ,Photosensitizer ,Irradiation ,Mice, Inbred BALB C ,business.industry ,Lasers ,Gastroenterology ,Middle Aged ,medicine.disease ,Tumor tissue ,Liver ,Photochemotherapy ,chemistry ,Pheophorbide A ,Nd:YAG laser ,Hepatocellular carcinoma ,Female ,medicine.symptom ,Nuclear medicine ,business ,Neoplasm Transplantation - Abstract
To evaluate whether administration of pheophorbide-a, a new photosensitizer, followed by use of Q-switched Nd:YAG laser produces a photodynamic reaction, we administered pheophorbide-a to female nude mice (BALB/c-nu) that had been implanted with human hepatocellular carcinoma. Intra-tumoral concentrations of pheophorbide-a were measured by high-performance liquid chromatography. 3 hours after peroral administration of 1 mg/kg body weight, the intra-tumoral concentration was too low to reveal photodynamic effects. Peroral administration of 250 mg/kg body weight, intra-peritoneal administration of 5 mg/kg body weight, and intra-tumoral injection of 200 micrograms yielded 0.24 micrograms/g, 0.83 micrograms/g and 3.68-108 micrograms/g tumor concentrations, respectively. All tumors were irradiated interstitially using a Q-switched Nd:YAG laser at 1064 nm. Only tumors that had been intra-tumorally injected had areas of necrosis larger than those in control tumors. The results suggest that the injection of pheophorbide-a followed by interstitial irradiation using a Q-switched Nd:YAG laser does not induce sufficient photodynamic reaction if the intra-tumoral pheophorbide-a concentration is less than 0.83 micrograms/g tumor tissue, and that photodynamic therapy may be useful if the pheophorbide-a tumor concentration is within the range of 0.83-108 micrograms/g.
- Published
- 1991
- Full Text
- View/download PDF
47. Agglutination of human O erythrocytes by influenza A(H1N1) viruses freshly isolated from patients
- Author
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K. Haruki, T. Kimura, S. Minoshiro, Y. Seto, K. Shibe, and T. Murakami
- Subjects
Adult ,Erythrocytes ,Hemagglutination ,Influenza vaccine ,viruses ,Guinea Pigs ,Orthomyxoviridae ,Hemagglutinin (influenza) ,Viral Plaque Assay ,Virus ,Cell Line ,Influenza A Virus, H1N1 Subtype ,Virology ,Influenza, Human ,Animals ,Humans ,Hemadsorption ,Child ,Antigens, Viral ,Hemagglutination assay ,biology ,virus diseases ,Hemagglutination Tests ,biology.organism_classification ,Agglutination (biology) ,Titer ,Influenza A virus ,biology.protein ,Chickens - Abstract
The hemagglutinin titers of 10 influenza A(H1N1) viruses were examined using the erythrocytes of several species. Human O erythrocytes showed the highest agglutination titer to the viruses, whereas chicken erythrocytes showed a low titer. These findings were noted for at least 10 passages by serial dilutions of the viruses in Madin-Darby canine kidney (MDCK) cells. All influenza A(H1N1) viruses, plaque-cloned directly from throat-washing specimens of patients, also agglutinated human O but not chicken erythrocytes. The results of a hemadsorption test indicated that chicken erythrocytes possess less affinity to MDCK cells infected with the A/Osaka City/2/88(HlNl) strain than to those infected with the A/Yamagata/120/86(H1N1) strain which is used as an inactivated influenza vaccine in Japan. However, there were no significant differences between the A/Osaka City/2/88 and the A/Yamagata/120/86 strains in the hemagglutination inhibition test. Since human O erythrocytes have high agglutination activity to influenza A(H1N1) and also to A(H3N2) and B viruses in MDCK cells, these erythrocytes may be useful for the serological diagnosis of influenza.
- Published
- 1991
- Full Text
- View/download PDF
48. Effect of mivazerol, a alpha-agonist, on striatal norepinephrine concentration during transient forebrain ischemia in rats
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T, Kimura, K, Sato, T, Nishikawa, Y, Tobe, and Y, Masaki
- Subjects
Male ,Dose-Response Relationship, Drug ,Imidazoles ,Electroencephalography ,Sodium Chloride ,Corpus Striatum ,Rats ,Rats, Sprague-Dawley ,Disease Models, Animal ,Norepinephrine ,Neuroprotective Agents ,Prosencephalon ,Ischemic Attack, Transient ,Animals ,Adrenergic alpha-Agonists ,Chromatography, High Pressure Liquid - Abstract
We have previously reported that mivazerol, a alpha(2)-agonist, possibly provides neuroprotection against transient forebrain ischemia in rats. This study was designed to investigate the ability of mivazerol to attenuate ischemia-induced increase in striatal norepinephrine concentration after transient forebrain ischemia in rats.Male Sprague-Dawley rats, anesthetized with halothane, were assigned to one of three groups (n=10 each); control (C, normal saline 1 ml/kg), mivazerol 20 microg/kg (M20), and 40 microg/kg (M40) groups. Monitored variables included temporal muscle temperature (maintained at 37.5+/-0.1 degrees C), electroencephalogram, systolic/diastolic blood pressure, heart rate, arterial blood gases, and blood glucose concentrations. Thirty minutes after subcutaneous drug administration, forebrain ischemia was induced with hemorrhagic hypotension (systolic arterial pressure: 40-50 mmHg) and bilateral carotid artery occlusion for 10 min, and then the brain was reperfused. Norepinephrine concentration in the interstitial fluids in the striatum was analyzed using in vivo microdialysis in combination with high-performance liquid chromatography.Ischemia resulted in a prompt increase in norepinephrine concentrations in the striatum in all groups. However, there were no significant differences in norepinephrine concentrations in the striatum between the three groups at any period.Our results indicate that mivazerol did not attenuate ischemia-induced increase in striatal norepinephrine concentration. This suggests that the possible neuroprotective property of mivazerol is not related to inhibition of norepinephrine release in the brain.
- Published
- 2008
49. Aberrantly spliced alpha-dystrobrevin alters alpha-syntrophin binding in myotonic dystrophy type 1
- Author
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M, Nakamori, T, Kimura, T, Kubota, T, Matsumura, H, Sumi, H, Fujimura, M P, Takahashi, and S, Sakoda
- Subjects
Transcription, Genetic ,Reverse Transcriptase Polymerase Chain Reaction ,Myocardium ,RNA Splicing ,Calcium-Binding Proteins ,Age Factors ,Membrane Proteins ,Muscle Proteins ,Mice, Transgenic ,Exons ,Transfection ,Cell Line ,Polymyositis ,Alternative Splicing ,Mice ,Sarcolemma ,Muscular Dystrophies, Limb-Girdle ,Species Specificity ,Trinucleotide Repeats ,Reference Values ,Dystrophin-Associated Proteins ,Animals ,Myotonic Dystrophy ,Motor Neuron Disease ,Muscle, Skeletal - Abstract
Myotonic dystrophy type 1 (DM1) is a multisystemic disorder caused by a CTG repeat expansion in the DMPK gene. Aberrant messenger RNA (mRNA) splicing of several genes has been reported to explain some of the symptoms in DM1, but the cause of muscle wasting is still unknown. By contrast, many forms of muscular dystrophy are caused by abnormalities of the dystrophin-glycoprotein complex (DGC). alpha-Dystrobrevin is a key component of the DGC in striated muscle and plays important roles in maturation and signal transduction by interacting with alpha-syntrophin. The goal of this study was to investigate alternative splicing of alpha-dystrobrevin in DM1 and examine alpha-syntrophin binding of different alpha-dystrobrevin splice isoforms.Splicing patterns of alpha-dystrobrevin in DM1 muscle were studied by reverse-transcriptase PCR. Expression of the variant splice isoform was examined by immunoblotting and immunohistochemistry. Alternatively spliced isoforms were expressed in cultured cells to investigate interaction with alpha-syntrophin. alpha-Syntrophin expression was examined by immunoblotting.alpha-Dystrobrevin mRNA including exons 11A and 12 was increased in both skeletal and cardiac muscle of DM1 patients. The aberrantly spliced alpha-dystrobrevin isoform was localized to the sarcolemma, and showed increased binding with alpha-syntrophin. Furthermore, levels of alpha-syntrophin associated with the DGC were increased in DM1 muscle.Alternative splicing of alpha-dystrobrevin is dysregulated in myotonic dystrophy type 1 (DM1) muscle, resulting in changes in alpha-syntrophin binding. These results raise the possibility that effects on alpha-dystrobrevin splicing may influence signaling in DM1 muscle cells.
- Published
- 2008
50. An orthotopic skull base model of malignant meningioma
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Gilson S, Baia, Eduard B, Dinca, Tomoko, Ozawa, Edna T, Kimura, Michael W, McDermott, C David, James, Scott R, VandenBerg, and Anita, Lal
- Subjects
Time Factors ,Tumor Suppressor Proteins ,Green Fluorescent Proteins ,Mice, Nude ,Tetrazolium Salts ,Skull Base Neoplasms ,nervous system diseases ,Dacarbazine ,Gene Expression Regulation, Neoplastic ,Disease Models, Animal ,Mice ,Thiazoles ,DNA Repair Enzymes ,Cell Line, Tumor ,otorhinolaryngologic diseases ,Meningeal Neoplasms ,Temozolomide ,Animals ,Female ,Meningioma ,neoplasms ,Antineoplastic Agents, Alkylating ,DNA Modification Methylases ,Neoplasm Transplantation ,Research Articles - Abstract
Meningioma tumor growth involves the subarachnoid space that contains the cerebrospinal fluid. Modeling tumor growth in this microenvironment has been associated with widespread leptomeningeal dissemination, which is uncharacteristic of human meningiomas. Consequently, survival times and tumor properties are varied, limiting their utility in testing experimental therapies. We report the development and characterization of a reproducible orthotopic skull‐base meningioma model in athymic mice using the IOMM‐Lee cell line. Localized tumor growth was obtained by using optimal cell densities and matrigel as the implantation medium. Survival times were within a narrow range of 17–21 days. The xenografts grew locally compressing surrounding brain tissue. These tumors had histopathologic characteristics of anaplastic meningiomas including high cellularity, nuclear pleomorphism, cellular pattern loss, necrosis and conspicuous mitosis. Similar to human meningiomas, considerable invasion of the dura and skull and some invasion of adjacent brain along perivascular tracts were observed. The pattern of hypoxia was also similar to human malignant meningiomas. We use bioluminescent imaging to non‐invasively monitor the growth of the xenografts and determine the survival benefit from temozolomide treatment. Thus, we describe a malignant meningioma model system that will be useful for investigating the biology of meningiomas and for preclinical assessment of therapeutic agents.
- Published
- 2007
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