Kayoko Saiki

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Near-infrared spectroscopy (NIRS) was used to measure frontal regional cerebral blood volume (rCBV) in a person whose brain was under the influence of pharmacological agents while the person was performing a complex task. Fourteen healthy participants were administered Uchida-Kraepelin psychodiagnostic (UKP) tests before and after caffeine intake, and the(More)
The characteristics of the mass spectra of sixty steroids were investigated using atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). In APCI-MS, the drift voltage and nebulizer temperature affected the appearance of molecular ions. Solvent adducted ions [M+H+CH3CN]+ and [M+H+H2O]+ were decreased with an increase in drift voltage. The(More)
Ornithine transcarbamylase (OTC) deficiency is the most common inborn error of the urea cycle. Although a combination of molecular methods have been used including DNA sequencing of all 10 exons and exon-intron boundaries of OTC gene, only approximately 80% of patients with OTC deficiency are found to have mutations. We report two known and three novel(More)
We established an improved method for quantification of phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) molecular species in neonatal serum using high-performance liquid chromatography coupled tandem mass spectrometry (LC-MS/MS). A multiple reaction monitoring (MRM) mode of positive ionization for MS/MS was used. The method involved purification(More)
We determined the optical isomer of the 2-hydroxyglutaric acid (2HG) that was elevated in the urine of five Japanese children with a mild form of glutaric aciduria type II (GA2), caused by a deficiency of electron transfer flavoprotein (ETF) or ETF-ubiquinone oxidoreductase (ETF-QO). The D- and L-enantiomers of 2HG were separated by capillary gas(More)
Mutations in the gene encoding UDP-glucuronosyltransferase 1A1 (UGT1A1) may reduce the glucuronidation of estradiol, bilirubin, etc. In the present study, we used a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to assay the activities of recombinant mutated UGT1A1 toward 17beta-estradiol (E2), by determining its glucuronide (E2G) content.(More)
Unconjugated steroids were extracted with dichloromethane from the serum of pre-term neonates. Conjugated steroid fraction in the residue was separated and purified by high performance liquid chromatography. The purified steroid fraction was subjected to enzyme (arylsulfatase from Helix pomatia) or acid hydrolysis. Liberated steroid was analyzed by gas(More)
Lysophosphatidylcholine (LPC) has various stimulatory effects on many types of immune cells. The purpose of our study was to characterize blood LPC levels and to determine the composition of LPC molecular species (LPCs) in the neonatal period. Thirty-six neonates were enrolled in this study and then grouped according to birth-weight as follows: non-very low(More)