著者

Y. Shimojo T. Nishimura H. Hazama N. Ito K. Awazu

出版者

International Phototherapy Association

雑誌

LASER THERAPY (ISSN:08985901)

巻号頁・発行日

vol.29, no.1, pp.61-72, 2020 (Released:2020-07-17)

参考文献数

59

被引用文献数

7 12

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Background and Objectives: Computational clinical trial (CCT) in the field of laser medicine promotes clinical application of novel laser devices, because this trial carried out based on numerical modeling of laser-tissue interactions and simulation of a series of treatment process. To confirm the feasibility of the computational clinical trial of skin treatment with a novel picosecond laser, this paper presents an evaluation method of the safety. Study Design/Materials and Methods: In this method, the light propagation and thermal diffusion process after ultrashort light pulse irradiation to a numerical skin model is calculated and the safety based on the photothermal damage is evaluated by computational modeling and simulation. As an example, the safety of a novel picosecond laser device was examined by comparing with several laser devices approved for clinical use. Results: The ratio of the maximum thermal damage induced by picosecond laser irradiation was 1.2 × 10-2 % at the epidermis, while that caused by approved laser irradiation was 99 % at the capillary vessels. The numerical simulation demonstrated that less thermal damage was observed compared with the approved devices. The results show the safety simulated by photothermal damage calculation was consistent with the reported clinical trials. Conclusions: This computational clinical trial shows the feasibility of applying computational clinical trials for the safety evaluation of novel medical laser devices. In contrast to preclinical and clinical tests, the proposed computational method offers regulatory science for appropriately and quickly predicting and evaluating the safety of a novel laser device.

著者

Yukiko Kimura Fusae T. Nishimura Shuntaro Abe Tatsushige Fukunaga Hideji Tanii Kiyofumi Saijoh

出版者

The Japanese Society of Toxicology

雑誌

The Journal of Toxicological Sciences (ISSN:03881350)

巻号頁・発行日

vol.34, no.1, pp.89-97, 2009-02-01 (Released:2009-02-01)

参考文献数

32

被引用文献数

10 12

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Class II alcohol dehydrogenase (π-ADH), encoded by alcohol dehydrogenase (ADH4), is considered to contribute to ethanol (EtOH) oxidation in the liver at high concentration. Four single nucleotide polymorphisms (SNPs) were found in the promoter region of this gene. Analysis of genotype distribution in 102 unrelated Japanese subjects revealed that four loci were in strong linkage disequilibrium and could be classified into three haplotypes. The effects of these polymorphisms on transcriptional activity were investigated in HepG2 cells. Transcriptional activity was significantly higher in cells with the -136A allele than in those with the -136C allele. To investigate whether this difference in transcriptional activity caused a difference in EtOH elimination, previous data on blood EtOH changes after 0.4 g/kg body weight alcohol ingestion were analyzed. When analyzed based on aldehyde dehydrogenase-2 gene (ALDH2) 487Glu/Lys genotype, the significantly lower level of EtOH at peak in subjects with -136C/A and -136A/A genotype compared with subjects with -136C/C genotype indicated that -136 bp was a suggestive locus for differences in EtOH oxidation. This effect was observed only in subjects with ALDH2 487Glu/Glu. These results suggested that the SNP at -136bp in the ADH4 promoter had an effect on transcriptional regulation, and that the higher activity of the -136A allele compared with the -136C allele caused a lower level of blood EtOH after alcohol ingestion; that is, individuals with the -136A allele may consume more EtOH and might have a higher risk for development of alcohol dependence than those without the -136A allele.