Gyung-Jae Oh

Prognostic potential of glutathione S-transferase M1 and T1 null genotypes for gastric cancer progression.

To improve understanding of glutathione S-transferase (GST) behavior in terms of a development and prognostic factor for gastric adenocarcinoma, we investigated the association between the GSTM1 and GSTT1 null genotypes and gastric cancer risk or the prognostic value of the GSTM1 and GSTT1 null genotypes was evaluated. Using a polymerase chain reaction-based method, the frequencies of GSTM1 and GSTT1 genotypes and prognostic factors, such as staging, differentiation, and histologic type (intestinal vs. diffuse), were evaluated in 80 patients with curatively resected primary gastric adenocarcinoma. The frequencies of GSTM1 and GSTT1 null individuals were higher in the gastric cancer group, but the differences were not statistically significant (for GSTM1 null odds ratio (OR)=0.86; 95% confidence interval (CI)=0.49-1.51 and for GSTT1, OR=0.97; 95% CI=0.55-1.71). Since the GSTM1 and GSTT1 null genotypes are potential indicators of gastric adenocarcinoma, we examined the relationship between the GSTM1 and GSTT1 genotypes and prognostic factors. In terms of the histologically diffuse type of cancer, GSTM1 indicated an approximately 3.24-fold increase (OR=3.24; 95% CI=1.05-10.17). With respect to gastric cancer differentiation, the frequency of the GSTM1 null genotype was linked with a statistically significant increase in risk (3.42-fold) for the high-grade type (OR=3.42; CI=1.02-13.24). Our results indicate that there is no obvious relationship between GSTM1 and GSTT1 polymorphisms and the development of gastric cancer. However, in Korean gastric adenocarcinoma patients the GSTM1 null genotype appears to be associated with a poorer prognosis.

The suggestive association of eotaxin-2 and eotaxin-3 gene polymorphisms in Korean population with allergic rhinitis

The eotaxin gene family (eotaxin, eotaxin-2 and eotaxin-3) has been implicated in the recruitment of eosinophils, basophiles and Th2 lymphocytes that are central aspects of allergic diseases. To determine whether single-nucleotide polymorphisms (SNPs) of the eotaxin-2 and eotaxin-3 genes are associated with susceptibility to allergic rhinitis, we scanned 178 allergic rhinitis patients and 281 controls without allergic rhinitis using the direct sequencing and single-base extension (SBE) methods. We also calculated the haplotype frequencies between +179T>C and +275C>T of eotaxin-2 and +2497T>G of eotaxin-3 in both controls and allergic rhinitis patients. The haplotype frequency between controls and allergic rhinitis patients was suggestively associated (P=0.0001). The genotype frequencies of eotaxin-3 +2497T>G in allergic rhinitis patients were suggestively different from those in non-allergic rhinitis controls (P=<0.0007). Our results strongly suggest that the SNP of eotaxin-3 might be associated with susceptibility to allergic rhinitis.

Identification of single nucleotide polymorphisms in the TNFRSF17 gene and their association with gastrointestinal disorders

TNFRSF17 is preferentially expressed in mature B lymphocytes, and may be important for the development of B cells. TNFRSF17 is selected as a candidate susceptibility gene to IBD pathogenesis by our cDNA microarray analysis, and we showed the specific expression of TNFRSF17 in resting and activated CD19+ cells obtained from human blood. We identified four SNPs (g-1729G>A, g.2295T>C, g.2445G>A and g.2493G>A) and one variation site (g.894delT) in the TNFRSF17 gene using direct sequencing analysis. In addition, the association of the genotype and allelic frequencies of these SNPs was studied in healthy controls and in patients with ulcerative colitis (UC) or irritable bowel syndrome (IBS). Although, the genotype and allelic frequencies of these SNPs, in the UC and IBS patients, were not significantly different from those in the healthy controls, the distribution of the AAG, GGA, AGG and AAA haplotypes, of the SNPs (g.-1729G>A, g.2445G> A and g.2493G>A) associated with the TNFRSF17 gene, in the UC patients, were notably different from those of the healthy controls (P = 0.002, 0.002, 4.7E-4 and 3.3E-6, respectively). Moreover, the frequencies of the AAG, AGG, GAG and GAA haplotypes were significantly different in the IBS patients compared to the healthy controls (P = 4.2E-5, 4.4E-17, 1.8E-22 and 1.6E-10, respectively). These results suggest that the haplotypes of the TNFRSF17 polymorphisms might be associated with UC and IBS susceptibility.

Patterns of three-phase bone scintigraphy according to the time course of complex regional pain syndrome type I after a stroke or traumatic brain injury.

We have proposed to evaluate different patterns represented on 3-phase bone scintigraphy (TPBS) according to the time course of complex regional pain syndrome (CRPS) type I (CRPS-I) after a stroke or traumatic brain injury. TPBS was performed in 50 consecutive patients for the evaluation of CRPS. We divided the patients into CRPS and non-CPRS groups based on the use of International Association for the Study of Pain criteria. We evaluated the changes on TPBS according to clinical stages based on time course. In the early acute stage within 6 weeks, minimal uptake on all TPBS phases was observed in the 90% of the patients in the CRPS-I group and in 75% of the patients in the non-CRPS group. In the acute stage of CRPS in the range of 2 to 20 weeks, moderately increased uptake was seen for 78%, 83%, and 83% of the patients in the CRPS group for the 3 phases, respectively. However, only 16% of the patients in the non-CRPS group had moderately increased uptake as seen on all TPBS phases. In the late stage of more than 21 weeks, there was no distinct difference in uptake between the 2 groups. A sequential change during the time course for the CPRS-I group was statistically significant (P < 0.05). Therefore, performance of follow-up TPBS may be useful to diagnose CPRS-I in uncertain cases of the early acute stage after a stroke or traumatic brain injury.

Identifying Polymorphisms in IL-31 and Their Association with Susceptibility to Asthma.

Background Interleukin 31 (IL-31) is a T helper type 2 effector cytokine that plays an important role in the pathogenesis of atopic and allergic diseases. IL-31 may be involved in promoting allergic inflammation and in inducing airway epithelial responses such as allergic asthma. Methods Single-base extension analysis was used to detect the genotypes of IL-31 single nucleotide polymorphisms (SNPs), and we compared the genotype and allele frequencies of the IL-31 SNPs between patients with asthma and healthy controls. Results There were no significant differences in the genotype and allele frequencies of the IL-31 SNPs between patients with asthma and healthy controls. Furthermore we compared the genotype and allele frequencies of IL-31 SNPs between patients with atopic asthma, those with non-atopic asthma and healthy controls. This showed that the SNPs were not associated with the susceptibility to atopic asthma. There were no significant differences in the haplotype frequencies of IL-31 SNPs between patients with asthma and healthy controls. In patients with asthma, the IL-31 SNPs were significantly correlated with total serum levels of IgE (p=0.035). Conclusions Our results indicate that, the IL-31 SNPs may be associated with IgE production in patients with asthma.

INHIBITORY EFFECT OF IMMUNOGLOBULIN E PRODUCTION BY JIN-DEUK-CHAL (SIEGESBECKIA ORIENTALIS)

Elevated levels of immunoglobulin (Ig) E are associated with immediate-type allergic reactions. Jin-deuk-chal is the whole plant of Siegesbeckia orientalis (SO) sL. Immunization of mice with small amounts of protein antigens on alum results in several fold increases in total plasma IgE, much of it specific for the immunizing antigen. In the present study, we investigated the effect of Siegesbeckia orientalis (SO) on IgE production. SO inhibited the plasma levels of IgE induced by antigens. The effects of SO on the interleukin (IL)-4-dependent IgE response by mouse whole spleen cells were studied. IL-4 dependent IgE production of lipopolysaccharide (LPS)-stimulated whole spleen cells was inhibited by SO. In addition, using U266B1 human IgE-bearing B cells, we found that SO inhibited the production of IgE activated by LPS plus IL-4. These results suggest that SO have antiallergic activity by inhibition of IgE production from B cells.

HbA1c is significantly associated with arterial stiffness but not with carotid atherosclerosis in a community-based population without type 2 diabetes: The Dong-gu study.

OBJECTIVES We examined the associations between HbA1c levels and various atherosclerotic vascular parameters among adults without diabetes from the general population. METHODS A total of 6500 community-dwelling adults, who were free of type 2 diabetes and ≥50 years of age, were included. High-resolution B-mode ultrasound was used to evaluate carotid artery structure, including intima-media thickness (IMT), plaque, and luminal diameter. Brachial-ankle pulse wave velocity (baPWV), which is a useful indicator of systemic arterial stiffness, was determined using an automatic waveform analysis device. RESULTS No significant associations were observed between HbA1c, carotid IMT, plaque, or luminal diameter in a fully adjusted model. However, the odds ratio (95% confidence interval) for high baPWV (defined as the highest quartile) increased by 1.43 (1.19-1.71) per 1% HbA1c increase after adjusting for conventional risk factors in a multivariate logistic regression analysis. In addition, HbA1c was independently associated with baPWV in a multivariate linear regression analysis. CONCLUSIONS High-normal HbA1c level was independently associated with arterial stiffness, but not with carotid atherosclerotic parameters, in the general population without diabetes. Our results suggest that the functional atherosclerotic process may already be accelerated according to HbA1c level, even at a level below the diagnostic threshold for diabetes.

Representative levels of blood lead, mercury, and urinary cadmium in youth: Korean Environmental Health Survey in Children and Adolescents (KorEHS-C), 2012–2014

BACKGROUND This study examined levels of blood lead and mercury, and urinary cadmium, and associated sociodemographic factors in 3-18 year-old Korean children and adolescents. MATERIALS AND METHODS We used the nationally representative Korean Environmental Health Survey in Children and Adolescents data for 2012-2014 and identified 2388 children and adolescents aged 3-18 years. The median and 95th percentile exposure biomarker levels with 95% confidence intervals (CIs) were calculated. Multivariate regression analyses were performed on log transformed exposure biomarker levels adjusted for age, sex, area, household income, and fathers education level. The median exposure biomarker levels were compared with data from Germany, the US, and Canada, as well as the levels of Korean children measured at different times. RESULTS The median levels of blood lead and mercury, as well as urinary cadmium were 1.23μg/dL, 1.80μg/L, and 0.40μg/L (95% CIs, 1.21-1.25, 1.77-1.83, and 0.39-0.41, respectively). The blood lead levels were significantly higher in boys and younger children (p<0.0001) and children with less educated fathers (p=0.004) after adjusting for covariates. Urinary cadmium level increased with age (p<0.0001). The median levels of blood mercury and urinary cadmium were much higher in Korean children and adolescents than those in their peers in Germany, the US, and Canada. Blood lead levels tended to decrease with increasing age and divergence between the sexes, particularly in the early teen years. Median levels of blood lead and urinary cadmium decreased since 2010. CONCLUSION Sociodemographic factors, including age, sex, and fathers education level were associated with environmental exposure to heavy metals in Korean children and adolescents. These biomonitoring data are valuable for ongoing surveillance of environmental exposure in this vulnerable population.

Korean Stroke Cohort for functioning and rehabilitation (KOSCO): study rationale and protocol of a multi-centre prospective cohort study

BackgroundDevelopment of a long-term stroke care plan requires serial assessment of long-term patient function and consideration of caregiver mood. However, to date, few comprehensive cohort studies have included both stroke patients and caregivers.Methods/DesignKOSCO is a large, multi-centre prospective cohort study for all acute first-ever stroke patients admitted to participating hospitals in nine distinct areas of Korea. This study is designed as a 10-year, longitudinal follow-up investigating the residual disabilities, activity limitations, and quality of life issues arising in patients suffering from first-ever stroke. The main objectives of this study are to identify the factors that influence residual disability and long-term quality of life. The secondary objectives of this study are to determine the risk of mortality and recurrent vascular events in patients with acute first-ever stroke. We will investigate longitudinal health behaviors and patterns of healthcare utilization, including stroke rehabilitation care. We will also investigate the long-term health status, mood, and quality of life in stroke patient caregivers. In addition, we will identify baseline and ongoing characteristics that are associated with our secondary outcomes.DiscussionKOSCO is a prospective, multi-centre, 10-year longitudinal follow-up study investigating the residual disabilities, activity limitations, and quality of life issues arising in patients suffering from first-ever stroke.

The immunogenicity of a single dose of hepatitis A virus vaccines (Havrix® and Epaxal®) in Korean young adults.

Purpose Assessing the immunogenicity of a single dose of hepatitis A virus (HAV) vaccines is important because some people receive only a single dose. However, previous studies have shown variable results and have not examined the effects of demographic characteristics other than gender. This study was performed to examine the immunogenicity of a single dose of HAV vaccine according to the vaccine type and demographic characteristics in young adults. Materials and Methods Seronegative medical school students were randomly allocated to receive either Havrix or Epaxal. Results After approximately 11 months, the seroconversion rate in 451 participants was 80.7%. In men, the Havrix group showed a significantly higher seroconversion rate (81.9%) than the Epaxal group (69.2%), whereas both vaccine groups showed similarly high immunogenicity in women (Havrix: 90.1%, Epaxal: 92.9%; P for interaction=0.062). According to the results of a multivariate analysis, Epaxal showed significantly lower immunogenicity than Havrix only in men. Age, obesity, drinking, smoking, and follow-up time did not significantly affect seroconversion in either gender. Conclusion The seroconversion rate of single-dose HAV vaccines was low in men, particularly in those who received Epaxal. Our results suggest that gender effects should be considered when comparing the immunogenicity of different HAV vaccines.