Keita Hirai

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Lamotrigine (LTG) is used to treat epilepsy. The variability of LTG pharmacokinetics among individuals may be attributed to polymorphisms in the genes of uridine diphosphate glucuronosyltransferases (UGTs) 1A4 and UGT2B7 and/or combination with other drugs. In this study, we evaluated the association between LTG concentrations and patient characteristics(More)
This paper develops a color image recovery system from a color-embedded gray image. A reversible color-to-gray algorithm is an effective technique from several viewpoints such as running cost, data quantity, and security in practical applications. Most of the conventional algorithms work only on electronic gray images in the closed computer world, and do(More)
PURPOSE Valproic acid (VPA), which is widely used to treat epilepsy, migraine, and bipolar disorder, can causes severe hyperammonemia. However, the mechanism responsible for this adverse effect is not readily apparent. We previously reported that phenytoin coadministration is a strong risk factor for the development of hyperammonemia during VPA-based(More)
The long-term efficacy of tolvaptan, a vasopressin V2 receptor antagonist, has been reported. However, the safety of long-term treatment remains to be fully elucidated. We assessed the safety profile of tolvaptan with respect to hypernatremia. This retrospective study included 371 patients treated with tolvaptan. Risk factors for hypernatremia (serum sodium(More)
A method is proposed for estimating a generalized bispectral matrix for fluorescent objects. The Donaldson matrix is constructed on the wide wavelength range over ultraviolet and visible wavelengths. We use neither an ultraviolet light (black light) nor a monochromator. We present an algorithm for estimating precisely the general shape of luminescent(More)