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Featured researches published by Rina Kurihara.


Journal of Biological Chemistry | 2006

Effects of peripheral cannabinoid receptor ligands on motility and polarization in neutrophil-like HL60 cells and human neutrophils

Rina Kurihara; Yumi Tohyama; Satoshi Matsusaka; Hiromu Naruse; Emi Kinoshita; Takayuki Tsujioka; Yoshinao Katsumata; Hirohei Yamamura

The possible role of the peripheral cannabinoid receptor (CB2) in neutrophil migration was investigated by using human promyelocytic HL60 cells differentiated into neutrophil-like cells and human neutrophils isolated from whole blood. Cell surface expression of CB2 on HL60 cells, on neutrophil-like HL60 cells, and on human neutrophils was confirmed by flow cytometry. Upon stimulation with either of the CB2 ligands JWH015 and 2-arachidonoylglycerol (2-AG), neutrophil-like HL60 cells rapidly extended and retracted one or more pseudopods containing F-actin in different directions instead of developing front/rear polarity typically exhibited by migrating leukocytes. Activity of the Rho-GTPase RhoA decreased in response to CB2 stimulation, whereas Rac1, Rac2, and Cdc42 activity increased. Moreover, treatment of cells with RhoA-dependent protein kinase (p160-ROCK) inhibitor Y27632 yielded cytoskeletal organization similar to that of CB2-stimulated cells. In human neutrophils, neither JWH015 nor 2-AG induced motility or morphologic alterations. However, pretreatment of neutrophils with these ligands disrupted N-formyl-l-methionyl-l-leucyl-l-phenylalanine (fMLP)-induced front/rear polarization and migration and also substantially suppressed fMLP-induced RhoA activity. These results suggest that CB2 might play a role in regulating excessive inflammatory response by controlling RhoA activation, thereby suppressing neutrophil migration.


International Journal of Legal Medicine | 2004

Mutations in 14 Y-STR loci among Japanese father-son haplotypes.

Rina Kurihara; Toshimichi Yamamoto; Rieko Uchihi; Shi-Lin Li; Takashi Yoshimoto; Hiroyuki Ohtaki; Kiyofumi Kamiyama; Yoshinao Katsumata

In the present study 161 Japanese father/son haplotype transfers in 147 pedigrees were analyzed at 14 Y-STRs with two multiplex PCR-based typing systems. Five isolated single repeat mutations were identified at the DYS389I, DYS439, Y-GATA-H4, DYS389II and DYS391 loci, and a pedigree showing triple alleles at the DYS385 locus (a duplicate locus) without allelic discrepancy between the father and son was also observed. The overall mutation rate estimated across the 14 Y-STRs in the Japanese population was 0.22%/locus/meiosis (95% C.I. 0.09–0.51%). This rate was not significantly different (p>0.05) from those of autosomal STRs and Y-STRs in other populations, including German, Austrian, Polish and Norwegian populations. Furthermore, 138 haplotypes were identified in 147 pedigrees with a haplotype diversity value of 0.9983. Therefore, a combination of the two systems should permit effective analysis with sufficient discriminatory power.


Journal of Chromatography B: Biomedical Sciences and Applications | 2001

Sensitive determination of pethidine in body fluids by surface ionization organic mass spectrometry.

Akira Ishii; Rina Kurihara; Kanako Watanabe-Suzuki; Takeshi Kumazawa; Hiroshi Seno; Hajime Matsushima; Osamu Suzuki; Yoshinao Katsumata

We have presented a simple and sensitive method for determining pethidine, a narcotic analgesic drug in body fluids by gas chromatography (GC)/surface ionization organic mass spectrometry (SIOMS). Good linearity was obtained in the range of 0.625-25 ng/ml of whole blood and urine by mass chromatography, and in the range of 0.05-2 ng/ml of whole blood by selected ion monitoring (SIM). Pethidine and diphenylpyraline (internal standard) were extracted from body fluids with Bond Elut Certify cartridges; their recoveries were above 95%. The detection limits (signal-to-noise ratio=3) were estimated to be 0.2 ng/ml of whole blood or urine by mass chromatography, 0.02 ng/ml of whole blood by SIM.


Journal of Chromatography B: Biomedical Sciences and Applications | 2001

Sensitive determination of four general anaesthetics in human whole blood by capillary gas chromatography with cryogenic oven trapping.

Takashi Kojima; Akira Ishii; Kanako Watanabe-Suzuki; Rina Kurihara; Hiroshi Seno; Takeshi Kumazawa; Osamu Suzuki; Yoshinao Katsumata

Four general anaesthetics, sevoflurane, isoflurane, enflurane and halothane, in human whole blood, have been found measurable with very high sensitivity by capillary gas chromatography-flame ionization detection (GC-FID) with cryogenic oven trapping upon injection of headspace (HS) vapor sample. To a 7-ml vial, containing 0.48 ml of distilled water and 20 microl of internal standard solution (5 microg), a 0.5-ml of whole blood sample spiked with or without anaesthetics, was added, and the mixture was heated at 55 degrees C for 15 min. A measure of 10 ml HS vapor was injected into the GC in the splitless mode at -40 degrees C oven temperature, which was programmed up to 250 degrees C. All four peaks were clearly separated; no impurity peaks were found among their peaks. Their extraction efficiencies were about 10%. The calibration curves showed good linearity in the range of 0.5-20 microg/ml; their detection limits were 10-100 ng/ml, which are almost comparable to those by previous reports. The coefficients of intra-day and day-to-day variations were 6.5-9.8 and 7.3-17.2%, respectively. Isoflurane or enflurane was also measured from whole blood samples in which three volunteers inhaled each compound.


Legal Medicine | 2002

Identification and characterization of 17 phenothiazine compounds by capillary high-performance liquid chromatography/fast atom bombardment mass spectrometry

Yasushi Mizuno; Keizo Sato; Toshiyuki Sano; Rina Kurihara; Takashi Kojima; Yoshinori Yamakawa; Akira Ishii; Yoshinao Katsumata

Phenothiazines are widely prescribed as neuroleptics; some are used as antihistaminics. These compounds are important in clinical and forensic toxicology. Seventeen phenothiazine compounds with heavy side chain structures have been found to be detectable by high-performance liquid chromatography/fast atom bombardment-mass spectrometry (HPLC/FAB-MS) method. Authentic samples of the compounds were subjected to our HPLC/FAB-MS system; their mass spectra were obtained by positive and negative modes. Four typical phenothiazines, in the serum samples of two patients, were also analyzed. All 17 phenothiazines were sufficiently separated on the chromatogram. In the positive mode, all the base peaks were quasimolecular ions; their main fragment ions observed were [M-R(1)+CH(2)](+), [R(1)](+), [M-R(1)](+) and [M+H+Gly](+). In the negative mode, the base peaks were [Cl](-) for chlorpromazine, prochlorperazine and perphenazine, three compounds containing chloride. For the other compounds, they were [M-R(1)-CH(3)](-), [M-R(1)-CH(2)CH(3)](-) or [M-R(1)-(CH(3))(2)](-) ions. We observed [M+H](-) ions in all the compounds, however, the ir intensities were variable (3-74%). The spectra and mass chromatograms of four compounds and their metabolites in the extracted serum samples from two patients, were also obtained. The approximate detection limits for phenothiazines were less than 1 ng on-column in the positive mode, and about 1 microg on-column in the negative mode. We have succeeded in the identification and characterization of 17 phenothiazine compounds at therapeutic concentrations in body fluids using our HPLC/FAB-MS system. The present method would be useful in forensic toxicological practice.


Legal Medicine | 2001

Sensitive determination of midazolam and identification of its two metabolites in human body fluids by column-switching capillary high-performance liquid chromatography/fast atom bombardment–mass spectrometry

Toshiyuki Sano; Keizo Sato; Rina Kurihara; Yasushi Mizuno; Takashi Kojima; Yoshinori Yamakawa; Takamichi Yamada; Akira Ishii; Yoshinao Katsumata

Midazolam is a benzodiazepine and is widely prescribed for preanesthesia or general anesthesia. Overdose or intoxication cases of midazolam have been reported. In Japan, smuggled midazolam tablets could be involved in some criminal cases. Midazolam and its two metabolites were extracted by the solid-phase extraction method using Bond Elut SCX cartridges. The compounds were analyzed by on-line capillary high-performance liquid chromatography/fast atom bombardment-mass spectrometry. Midazolam and its two metabolites were well separated on the chromatogram, and each mass spectra gave [M+H](+) ion as a base peak. Deuterium-labeled midazolam was synthesized as an internal standard; it has enabled precise and reproducible quantitation of midazolam in blood samples. The calibration curve showed excellent linearity in the range of 2-200 ng/ml in spiked serum. The detection limit was 300 pg/ml (signal-to-noise ratio=3). The whole blood and urine samples from the victim of a homicide case were analyzed, and the midazolam concentration in the whole blood was estimated to be 163 ng/ml. The present method should be useful in clinical and forensic toxicology, because of its high sensitivity and specificity.


Legal Medicine | 2000

Sensitive determination of mianserin and setiptiline in body fluids by gas chromatography with surface ionization detection (GC-SID)

Akira Ishii; Rina Kurihara; Takashi Kojima; Toshiyuki Sano; Yasushi Mizuno; Yashinori Yamakawa; Yoshinao Katsumata

Tetracyclic antidepressants, mianserin and setiptiline, in human body fluids have been found measurable with high sensitivity by gas chromatography (GC) with surface ionization detection (SID). The compounds in human whole blood or urine samples were extracted by solid-phase extraction using Bond Elut C(18) cartridges. The recoveries of both compounds from the body fluids were above 85%. For quantitation of mianserin, 25 ng of setiptiline was used as internal standard; and for quantitation of setiptiline, vice versa. The calibration curves for spiked whole blood or urine samples were linear in the range of 1.25-50 ng/ml. The detection limit of mianserin and setiptiline was about 1 ng/ml, which is comparable to those obtained by the previous GC-mass spectrometry methods. Our method seems very useful for determination of mianserin and setiptiline in forensic and clinical toxicology, because of high sensitivity, low background impurities and easy handling of the GC instrument.


International Journal of Legal Medicine | 2003

Haplotype analysis with 14 Y-STR loci using 2 multiplex amplification and typing systems in 2 regional populations in Japan

Rieko Uchihi; Toshimichi Yamamoto; Kanako Usuda; Takashi Yoshimoto; Miwa Tanaka; Seisaku Tokunaga; Rina Kurihara; Katsushi Tokunaga; Yoshinao Katsumata


Biochemical and Biophysical Research Communications | 2005

Protein-tyrosine kinase, Syk, is required for CXCL12-induced polarization of B cells

Satoshi Matsusaka; Yumi Tohyama; Jinsong He; Yuhong Shi; Ryoichi Hazama; Tomomi Kadono; Rina Kurihara; Kaoru Tohyama; Hirohei Yamamura


Journal of Chromatography B | 2003

Sensitive determination of pethidine in body fluids by gas chromatography-tandem mass spectrometry

Akira Ishii; Miwa Tanaka; Rina Kurihara; Kanako Watanabe-Suzuki; Takeshi Kumazawa; Hiroshi Seno; Osamu Suzuki; Yoshinao Katsumata

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