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991.
Sugihara K Okayama T Kitamura S Yamashita K Yasuda M Miyairi S Minobe Y Ohta S 《Archives of toxicology》2008,82(1):5-11
The aryl hydrocarbon receptor (AhR) ligand activities of six known AhR ligands were compared in vivo and in vitro. The in vivo ligand activity was estimated in terms of induction of cytochrome P450 1A1/2 activities, i.e., ethoxyresorufin-O-dealkylase (EROD) and methoxyresorufin-O-dealkylase (MROD) activities, and in vitro ligand activity was evaluated with a recombinant yeast reporter gene assay. The
test chemicals were 3-methylcholanthrene (MC), β-naphthoflavone (β-NF), indirubin, indigo, 3,3′-diindolylmethane (DIM) and
diphenyl-p-phenylenediamine (DPPD). The first four showed potent AhR ligand activity in vitro, comparable with that of 2,3,7,8-tetrachlorodibenzo-p-dioxin, while DIM and DPPD showed weaker activity. Administration of MC and β-NF to mice caused significant induction of
EROD and MROD activities, while indirubin, indigo and DIM also induced these activities, but less potently. DPPD also induced
the activities, but was toxic at higher doses. These enhancing effects were lost or greatly reduced in Ahr-null mice (Ahr
−/−). Our results suggest that EROD and MROD activity assays are useful for evaluating the AhR ligand activity of chemicals in
vivo, where the biodynamics of the chemicals plays an important role. 相似文献
992.
Toyonaga Y Iwai N Motohiro T Sunakawa K Fujii R 《The Japanese journal of antibiotics》2008,61(3):172-183
A post-marketing clinical study was previously conducted in pediatric patients with respiratory infection to evaluate the pharmacokinetics, efficacy and safety of cefcapene pivoxil (CFPN-PI) fine granules for children. Based on the results from this study, we evaluated PK/PD breakpoints and clinical/bacteriological effects of CFPN-PI at free drug concentrations in pediatric patients with respiratory infection to determine an effective and safe dosage regimen of CFPN-PI. The following results were obtained from 61 pediatric patients evaluated in our research. 1) The response rate of pediatric respiratory infection to CFPN-PI was 100% for laryngopharyngitis, 84.6% for acute bronchitis, 100% for tonsillitis, 100% for pneumonia and 95.8% for all. 2) The bacteriological response (eradication rate of Haemophilus influenzae, Streptococcus pyogenes, Moraxella catarrhalis, Streptococcus pneumoniae, etc.) of pediatric respiratory infection to CFPN-PI was 87.5% for laryngopharyngitis, 66.7% for acute bronchitis, 75.0% for tonsillitis, 63.6% for pneumonia and 73.8% for all. 3) The blood concentration simulation demonstrated that the PK/PD breakpoint exceeding the time above MIC (TAM) of 40% after administration of CFPN-PI 3 mg/kg three times daily was 0.27 microg/mL. 4) The pediatric patients with respiratory infection were stratified by the TAM (%) of CFPN-PI into 40% to 100% (TAM > or = 40% group) and 0% to 40% (TAM < 40% group) to compare the clinical and bacteriological effects of CFPN-PI. The clinical and bacteriological response rates, respectively, were 97.4% and 77.8% in the TAM > or = 40% group, and 88.9% and 62.5% in the TAM < 40% group. There was no difference in the clinical effect between the two TAM-stratified groups. On the other hand, the bacteriological effect, i.e., eradication rate, tended to be higher in the TAM > or = 40% group than in the TAM < 40% group, although the between-group difference was not statistically significant. 相似文献
993.
Kenichi Nakajima Naoya Matsumoto Tokuo Kasai Shinro Matsuo Keisuke Kiso Koichi Okuda 《Annals of nuclear medicine》2016,30(3):188-199
As a 2-year project of the Japanese Society of Nuclear Medicine working group activity, normal myocardial imaging databases were accumulated and summarized. Stress-rest with gated and non-gated image sets were accumulated for myocardial perfusion imaging and could be used for perfusion defect scoring and normal left ventricular (LV) function analysis. For single-photon emission computed tomography (SPECT) with multi-focal collimator design, databases of supine and prone positions and computed tomography (CT)-based attenuation correction were created. The CT-based correction provided similar perfusion patterns between genders. In phase analysis of gated myocardial perfusion SPECT, a new approach for analyzing dyssynchrony, normal ranges of parameters for phase bandwidth, standard deviation and entropy were determined in four software programs. Although the results were not interchangeable, dependency on gender, ejection fraction and volumes were common characteristics of these parameters. Standardization of 123I-MIBG sympathetic imaging was performed regarding heart-to-mediastinum ratio (HMR) using a calibration phantom method. The HMRs from any collimator types could be converted to the value with medium-energy comparable collimators. Appropriate quantification based on common normal databases and standard technology could play a pivotal role for clinical practice and researches. 相似文献
994.
Masanobu?IbarakiEmail authorView authors OrcID profile Keisuke?Matsubara Kaoru?Sato Tetsuro?Mizuta Toshibumi?Kinoshita 《Annals of nuclear medicine》2016,30(10):690-698
Objective
Positron emission tomography (PET) enables quantitative measurements of various biological functions. Accuracy in data acquisition and processing schemes is a prerequisite for this. The correction of scatter is especially important when a 3D PET scanner is used. The aim of this study was to validate the use of a simplified calculation-based scatter correction method for 15O studies in the brain.Methods
We applied two scatter correction methods to the same 15O PET data acquired from patients with cerebrovascular disease (n = 10): a hybrid dual-energy-window scatter correction (reference method), and a deconvolution scatter correction (simplified method). The PET study included three sequential scans for 15O-CO, 15O-O2, and 15O-H2O, from which the following quantitative parameters were calculated, cerebral blood flow, cerebral blood volume, cerebral metabolic rate of oxygen, and oxygen extraction fraction.Results
Both scatter correction methods provided similar reconstruction images with almost identical image noise, although there were slightly greater differences in white-matter regions compared with gray matter regions. These differences were also greater for 15O-CO than for 15O-H2O and 15O-O2. Region of interest analysis of the quantitative parameters demonstrated that the differences were less than 10 % (except for cerebral blood volume in white-matter regions), and the agreement between the methods was excellent, with intraclass correlation coefficients above 0.95 for all the parameters.Conclusions
The deconvolution scatter correction despite its simplified implementation provided similar results to the hybrid dual-energy-window scatter correction. We consider it suitable for application in a clinical 15O brain study using a 3D PET scanner.995.
Keisuke Kakisaka Kazuyuki Ishida Kojiro Kataoka Yuji Suzuki Shunichi Yanai Hidekatsu Kuroda Tamotsu Sugai Takayuki Matsumoto Yasuhiro Takikawa 《Pathology international》2016,66(7):404-408
Sclerosing cholangitis (SC) with granulocytic epithelial lesion (GEL) responds well to immunosuppression therapy. We treated a 42‐year‐old Japanese female with ulcerative colitis, who was admitted for further evaluation of both an elevated alkaline phosphatase level and dilated intrahepatic bile ducts. A liver biopsy on the fourth hospital day revealed the infiltration of neutrophils into the bile duct epithelium, which was diagnosed as GEL. Because her ulcerative colitis was in an active stage, prednisolone (PSL) therapy was started. After the administration of PSL, laboratory data dramatically decreased. A liver biopsy was performed on the 66th hospital day to confirm the lesion around bile ducts in the portal tract. The infiltration of neutrophils into the bile duct epithelium disappeared after PSL administration, and IgG4‐positive plasma cells were not found in the liver. Herein, we report a rare case of GEL‐positive SC. The present case provides early evidence of treatment‐induced histological changes as well as serial changes in biochemical data during the course of immunosuppression therapy. 相似文献
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999.
Keisuke Kurita Ryota Shin Tsutomu Tabei Daisuke Shiomi 《Genes to cells : devoted to molecular & cellular mechanisms》2019,24(3):259-265
Bacterial cells, including Escherichia coli and Bacillus subtilis, continuously elongate and divide. Although the cell width is maintained during cell cycle, the molecular mechanisms involved in its regulation remain unknown. MreB has been implicated to play a role in maintaining cell width. Several point mutations in mreB that affect cell width have been identified. The MreB protein forms clusters or polymers in the cell and moves along annular tracks perpendicular to the long axis. This rotation is coupled with peptidoglycan synthesis. Here, we focused on two MreB mutants, MreBA125V and MreBA174T. Cells producing MreBA125V and MreBA174T were thinner and thicker than WT cells, and MreBA125V and MreBA174T rotated faster and slower than WT MreB, respectively. We observed that the rotation rate correlated with the cell wall synthesis rate. Thus, we conclude that the velocity of MreB rotation also affects cell width, that is, the faster the MreB rotates, the thinner the cell width is. 相似文献
1000.
Yamamoto Kurara Uchida Keisuke Furukawa Asuka Tamura Tomoki Ishige Yuki Negi Mariko Kobayashi Daisuke Ito Takashi Kakegawa Tomoya Hebisawa Akira Awano Nobuyasu Takemura Tamiko Amano Tomonari Akashi Takumi Eishi Yoshinobu 《Immunologic research》2019,67(2-3):182-193
Immunologic Research - Bacterial catalase is important for intracellular survival of the bacteria. This protein of Propionibacterium acnes, one of possible causes of sarcoidosis, induces... 相似文献