• Sleep Medicine and Psychophysiology
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• v.20 no.2
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• pp.63-68
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• 2013

Objectives: Several evidence has been suggested that the circadian gene variants contribute to the pathogenesis of seasonal affective disorder. In this study, we aimed to investigate the polymorphism in RORA (Retinoid-related orphan receptor A) gene in relation to seasonal variations among healthy young adults in Seoul, Korea. Methods: A total of 507 young healthy adult subjects were recruited by advertisement. Seasonal variations were assessed by the Seasonality Pattern Assessment Questionnaire (SPAQ). Single-nucleotide polymorphism in the RORA rs11071547 gene was genotyped by PCR in 507 individuals. Considering summer type as confounding factor, we conducted analysis 478 subjects except 29 subjects of summer type. The Chi-square test was conducted to compare differences between groups of seasonals and non-seasonals. Association between genotypes and Global Seasonality Score (GSS) were tested using ANCOVA (Analysis of covariance). Results: In this sample, the prevalence of SAD was 12.1% (winter type 9.3%, summer type 2.8%). There is no significant difference in genotyping distribution of RORA rs11071547 between groups of seasonals and non-seasonals. Global seasonality score (GSS) and scores of all subscales except body weight and appetite were not significantly different between the group with C allele homozygote and the group with T allele homozygote and heterozygote (p-value 0.138). Scores of body weight and appetite were significantly higher in group with C allele homozygotes. Conclusion: These results suggest that RORA gene polymorphism play a role in seasonal variations in appetite and body weight and is associated with susceptibility to seasonal affective disorder in some degree in the population studied.

• Journal of Biomedical Engineering Research
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• v.35 no.5
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• pp.160-168
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• 2014

Continuous body temperature monitoring is useful and essential in diverse medical procedures such as infection onset detection, therapeutic hypothermia, circadian rhythm monitoring, sleep disorder assessment, and gynecological research. However, the existing thermometers are too invasive or intrusive to be applied to long-term body temperature monitoring. In our previous study, we invented the bi-medium deep body thermometer which can noninvasively and continuously monitor deep tissue temperature. And the ratio of thermal resistances expressed as K-value should be obtained to estimate body temperature with the thermometer and it can be different under various measurement environments. Although the device was proven to be useful through preliminary simulation test and small group of human study, the experimental environment was restrictive in our previous approach. In this study, a finite element simulation was executed to obtain the K-value and evaluate the accuracy of bi-medium thermometer under various measurement environments. In addition, K-value estimation equation was developed by analyzing the influence of 5 measurement environmental factors (medium length, medium height, tissue depth, blood perfusion rate, and ambient temperature) on K-value. The results revealed that the estimation accuracy of bi-medium deep body thermometer based on computer simulation was very high (RMSE < $0.003^{\circ}C$) in various measurement environments. Also, bi-medium deep body thermometer based on K-value estimation equation showed relatively accurate results (RMSE < $0.3^{\circ}C$) except for one case. Although the K-value estimation technology should be improved for more accurate body temperature estimation, the results of finite element simulation showed that bi-medium deep body thermometer could accurately measure various tissue temperatures under diverse environments.