Young Chang Tockgo

Epidemiologic picture of Kawasaki disease in Korea, 2000–2002

Background : The aim of this study was to investigate the incidence rate and epidemiologic patterns of Kawasaki disease in Korea for a 3 year period during 2000 to 2002.

Regulation of bcl-2 family in hydrogen peroxide-induced apoptosis in human leukemia HL-60 cells

Numerous types of cells have been shown to undergo apoptosis when exposed to oxidant agent such as hydrogen peroxide. In order to understand the functional relationship between the anti- and pro-apoptotic regulatory proteins in the cells under oxidant stress, we have studied the level of expression of apoptosis regulatory proteins, bcl-2 and bax, in human leukemia HL-60 cells. The exposure of HL-60 cells to different concentrations of H2O2 for 6 h resulted in a typical apoptosis of the cells as characterized by flow cytometry, cell cycle analysis, and DNA fragmantation. There was a block in G1 to S transition and apoptotic cells were mainly derived from S and G2 cells. Kinetic study demonstrated that the levels of both bcl-2-mRNA and -protein expression were decreased with the progression of cellular apoptosis whereas the level of bax-mRNA was unchanged but the expressed bax-protein was not detectable. Cycloheximide, a nonspecific translation inhibitor, did not prevent the hydrogen peroxide-mediated apoptosis in HL-60 cells. These results suggest that the regulation of bcl-2, but not of bax are important factor in the oxidative stress-induced apoptosis in HL-60 cells.

Effective treatment with fucoidin for perinatal hypoxic–ischemic encephalopathy in rats

Leukocyte-endothelial adhesion is a key step to initiate post-ischemic reperfusion injury in many organs. In this study, we found that the expressions of P-selectin mRNA and protein were increased in the ipsilateral hemisphere with a peak at 8 h after hypoxia-ischemia in immature brain. Such temporal profiles of P-selectin expression followed by hypoxia-ischemia are consistent with a role in the subsequent brain injury. Because fucoidin is known to inhibit P/L-selectin mediated leukocyte adhesion, we examined whether the treatment of fucoidin attenuates hypoxia-ischemia-induced neural damages. Treatment with fucoidin exhibited a substantial neuroprotective effect in a dose-dependent manner and inhibited the leukocyte adhesion significantly, as revealed by myeloperoxidase activity. These results suggest that anti-adhesion strategy may be an effective therapeutic application for the perinatal hypoxic-ischemic encephalopathy.

The Prevalence of Atopy and Asthma among University Freshmen in Seoul, Korea: Association with Obesity

The aims of this study were to investigate the prevalence of atopy, asthma, and obesity in university freshmen and to determine whether leptin is associated with bronchodilator reversibility in obesity. A total of 537 university freshmen completed International Study of Asthma and Allergies in Children (ISAAC) questionnaire and underwent skin prick testing and bronchodilator reversibility test. The prevalences of asthma, wheeze, and atopy were 10 (1.9%), 84 (15.6%), and 198 (36.9%), respectively. The mean (± SD) bronchodilator response (5.1 ± 4.4%) was higher in the overweight/obese men than in the normal male subjects (3.7 ± 3.2%, p < 0.05). The mean leptin level in the overweight/obese men was 5.55 ± 3.48 ng/mL, which was significantly higher than that (2.78 ± 1.65 ng/mL) of the normal male subjects. The prevalence of asthma among university freshmen is seriously under-diagnosed and leptin may play a role in bronchodilator reversibility in overweight/obese young men.

Seroprevalence to the circumsporozoite protein peptide antigen of Plasmodium vivax in Korean children.

Recently, malaria re‐emerged in the Republic of Korea (ROK), but there have been only a few reports on malaria seroprevalence. For the epidemiological study in children, a total of 1,176 serum samples were obtained from children and adolescent inhabitants from the three different regions, Pajoo, the Guro district in the western part of Seoul (Guro), and Ansan, from June to September 2002, when the transmission rate was high. Anti‐circumsporozoite protein (CSP) antibody levels were assessed in samples using an indirect enzyme‐linked immunosorbent assay (ELISA) method. Among the three regions, the highest IgG seroreactivity against the CSP antigen of Plasmodium vivax was found in the children from Pajoo (8.0%), followed by the children from Guro (3.2%), and those in Ansan (0.02%) had the lowest seroreactivity. In Pajoo, the profile of antibody response showed the highest in age 9, but decreased with age towards 12 years old. We found significant correlation between the seroprevalence and annual incidence in the investigated areas, suggesting that the area‐related patterns reflected the differences of inoculation rates in children.