Kyu Wol Yun

Age-related changes in erythropoietin immunoreactivity in the cerebral cortex and hippocampus of rats

Although oxidative stress may influence the fluid properties of blood, resulting in a potential decrement in blood flow and oxygen delivery to the brain during aging, very little is known about age-related changes in Epo expression. Therefore, we examined age-related changes in Epo expression in the cerebral cortex and hippocampus with an immunohistochemical technique. In aged rats, there was a significant decrease in Epo immunoreactivity in the pyramidal cells in the cortical regions. In the hippocampus of adult rats, a distinct immunoreactivity pattern was observed in the CA1-3 areas and dentate gyrus. In aged hippocampus, Epo immunoreactivity was significantly deceased in the pyramidal layer of CA1 regions, and the granule cell layer of dentate gyrus. It was noted that there was distinct pattern of Epo immunoreactivity in the pyramidal layer of CA2-CA3 region of aged rats. Epo immunoreactivity was relatively strong, but was observed only in the periphery of the cytoplasm. The first demonstration of age-related decreases in Epo expression in the cerebral cortex and hippocampus may provide useful data for investigating the pathogenesis of age-related neurodegenerative diseases, suggesting that age-related decreases in Epo may contribute to degenerative events following age-related decreases in brain flow and oxygen supply.

A Study on Correlation between Anxiety Symptoms and Suicidal Ideation.

Objective In South Korea, the number of deaths from suicide has increased in the last two decades, and suicide has become both a social and political problem. In this study, after controlling the variables influencing suicidal ideation, it was expected that it would be determined if anxiety symptoms are independently related to suicidal ideation. Methods Data were obtained from 327 psychiatric outpatients accomplished a self-reported questionnaire that included sociodemographic characteristics and clinical variables as well as self-rating scales for measuring the severity of ones anxiety, depression, and suicidal ideation. Logistic-regression analyses were used to determine the correlation between anxiety symptoms and significant suicidal ideation, adjusting for covariates. Results The patients with significant suicidal ideation were shown to be less educated, unemployed, never married, divorced, or separated by death, or living alone, and were shown to have a lower income, a drinking habit, a higher number of past suicide attempts, and more family members who committed suicide, than the patients without significant suicidal ideation. After adjusting the covariates influencing significant suicidal ideation, anxiety symptoms were associated with significant suicidal ideation. However, after adjusting for depressive symptoms, only the trait anxiety was associated with significant suicidal ideation. Conclusion These findings suggest that anxiety symptoms are an independent risk factor for suicidal ideation. Clinicians may thus use anxiety symptoms for the screening examination when evaluating suicidal ideation and risk, and will have to actively evaluate and treat the anxiety symptoms of patients with suicidal tendencies.

Influence of the Interaction between the Serotonin 1A Receptor C-1019G Polymorphism and Negative Life Stressors on the Development of Depression

The current study aimed to investigate the interaction between the serotonin 1A receptor gene (HTR1A) C-1019G polymorphism and recent negative life stressors on depression in a Korean community sample. The HTR1A C-1019G polymorphism was genotyped in 416 community-dwelling Koreans (156 males, 260 females; 44.37 ± 14.67 years old). Lifetime and current major depressive episodes were diagnosed using the Structured Clinical Interview for DSM-IV. The Center for Epidemiological Studies for Depression Scale (CES-D) was self-applied and face-to-face interviews investigating negative life stressors within the last 6 months were also performed. The results indicated that there were significant interactions between the C-1019G polymorphism and negative life stressors on CES-D scores (p = 0.02) as well as on current major depressive episodes (p = 0.002), but not on past major depressive episodes. G carriers alone had higher CES-D scores and more frequently experienced major depressive episodes after stressors. The interaction between the C-1019G polymorphism in HTR1A and recent negative life stressors accounted for current major depressive episodes and depressive symptoms. Our findings suggest that people with this gene variant may be more susceptible to developing depression especially after negative life stressors.

The Associations of Coping Mechanism with Arterial Stiffness in Hwa-Byung Patients

Objective The goal of this study is to assess the relationship between stress coping mechanisms and the risk of atherosclerosis in patients with Hwa-Byung. Methods The Korean version of the Ways of Coping Checklist (WOCC) was administered to 50 patients with Hwa-Byung (49.1±10.1 years, 6 males). Brachial-ankle pulse wave velocity (baPWV) and serum cholesterol level were assessed in all participants. Results After controlling for age, sex, diagnosis of hypertension, Body Mass Index (BMI), and serum cholesterol level, the score of seeking social support in coping strategies was negatively correlated with right and left baPWV (r=-0.356, p=0.016; r=-0.373, p=0.012, respectively). In addition, the score of active coping mechanism was negatively correlated with both sides of baPWV (r=-0.383, p=0.009; r=-0.389, p=0.008, respectively). Conclusion The seeking social support and active coping mechanism were inversely related to the severity of arterial stiffness in Hwa-Byung patients. Therefore, our result may suggest a possibility that coping strategies in Hwa-Byung patients are associated with the risk of atherosclerosis.