Sang Tae Choi

Plasma chemerin levels in rheumatoid arthritis are correlated with disease activity rather than obesity.

Joint Bone Spine - In Press.Proof corrected by the author Available online since jeudi 8 aout 2013

Immunological Impact of Taekwondo Competitions

Immunological changes in elite adolescent female athletes during Taekwondo competitions were investigated on-field. 6 female athletes (16.7 ± 0.8 year-old) volunteered and performed 5 bouts of demonstration Taekwondo competitions simulating real tournaments in intensity, duration, and break-time intervals on the same day. Blood samples were taken before, after the competitions and during the recovery, respectively. Immunological changes and oxidative stress in peripheral blood mononuclear cells were evaluated by flow-cytometry. During the competitions, exercise intensity was 92.2 ± 3.8% (86.1~95.7) of the maximal heart rate. Blood lactate increased immediately after the competitions (p=0.0165) and decreased to baseline during recovery. Intracellular reactive oxygen species (ROS) in the peripheral blood increased continuously during recovery (p<0.05, respectively). Natural killer cells increased immediately after the competitions (p=0.0006), and decreased during recovery. B and T cells increased immediately after the competitions and remained elevated throughout recovery (p<0.05, respectively). CD4/CD8 ratio after the competitions was decreased (p=0.0091) and returned to baseline during recovery. These results suggest that the immunological function of the elite female adolescent athletes could be attenuated after Taekwondo competitions. Further large-scaled Taekwondo studies on immunologic and apoptotic changes related to oxidative stress should be performed for improving and protecting the health of adolescent athletes.

Elevated Serum Homocysteine Levels Were Not Correlated with Serum Uric Acid Levels, but with Decreased Renal Function in Gouty Patients

Hyperhomocysteinemia is one of the important factors of the cardiovascular disease, and gout is well known to be associated with cardiovascular disease. There are a few reports on the serum homocysteine (Hcy) levels in patients with gout, however, the results showed discrepancies. In this study, we measured Hcy levels in patients with gout and examined factors associated with the levels of serum Hcy. Ninety-one male patients with gout and 97 age-matched healthy male controls were enrolled in the study. Serum uric acid levels were not significantly different between gout and healthy control groups. However, serum Hcy levels were significantly higher in patients with gout compared to controls (13.96±4.05 µM/L vs 12.67±3.52 µM/L, P=0.035). In gout group, patients with 1-2 stages of chronic kidney disease (CKD) had significantly lower serum Hcy than those with 3-5 stages of CKD (13.15±3.46 µM/L vs 17.45±4.68 µM/L, P<0.001). Multivariate linear analysis revealed an inverse association between serum Hcy and estimated glomerular filtration rate (eGFR) (β=-0.107, P<0.001). In conclusion, serum Hcy was elevated in male patients with gout. Hyperhomocysteinemia was not correlated with serum uric acid, but it was inversely associated with impaired renal function. Graphical Abstract

Usefulness of Serum Leucine-Rich Alpha-2 Glycoprotein as a Disease Activity Biomarker in Patients with Rheumatoid Arthritis

Our study aimed to investigate whether serum leucine-rich alpha-2-glycoprotein (LRG) levels are elevated in patients with rheumatoid arthritis (RA). In addition, we assessed their correlation with disease activity parameters and pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α). Our study included 69 patients with RA and 48 age- and sex-matched healthy controls. Serum concentrations of TNF-α and LRG were determined by enzyme-linked immunosorbent assay. Serum LRG concentrations were significantly elevated in patients with RA compared with those in healthy controls (30.8±14.4 vs. 22.2±6.1 ng/mL; P<0.001). In patients with RA, serum LRG levels were found to be correlated with disease activity score 28 (DAS28), erythrocyte sedimentation rate, and C-reactive protein levels (γ=0.671; γ=0.612; and γ=0.601, P<0.001, respectively), but not with serum TNF-α levels. Serum LRG levels in patients with an active disease status (DAS28≥2.6) were significantly higher than those in remission (DAS28<2.6) (36.45±14.36 vs. 24.63±8.81 ng/mL; P<0.001). Our findings suggest that serum LRG could contribute to the inflammatory process independent of TNF-α and it may be a novel biomarker for assessing inflammatory activity in patients with RA. Graphical Abstract

Levels of Plasma-soluble Triggering Receptor Expressed on Myeloid Cells-1 (sTREM-1) Are Correlated with Disease Activity in Rheumatoid Arthritis

Objective. To determine whether levels of plasma-soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) are elevated in patients with rheumatoid arthritis (RA) and whether levels are correlated with disease activity and other variables. Methods. Our study included 71 patients with RA and 50 age- and sex-matched healthy controls. Clinical characteristics and laboratory measures, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and 28-joint Disease Activity Score (DAS28) were assessed. Plasma levels of sTREM-1 and tumor necrosis factor-α (TNF-α) were measured by ELISA. Results. Patients with RA had significantly higher plasma sTREM-1 levels than healthy controls (170.10 ± 84.71 pg/ml vs 97.41 ± 40.64 pg/ml; p < 0.001). In patients with RA, plasma sTREM-1 levels were found to be correlated with DAS28, ESR, CRP, white blood cell counts, neutrophil counts, and plasma TNF-α levels (r = 0.329, p = 0.005; r = 0.241, p = 0.043; r = 0.314, p < 0.001; r = 0.261, p = 0.028; r = 0.278, p = 0.019; and r = 0.313, p = 0.009, respectively). Plasma sTREM-1 levels in patients with active disease status (DAS28 > 3.2) were significantly higher than in those with low disease status (DAS28 ≤ 3.2; 208.89 ± 100.14 pg/ml vs 150.29 ± 68.70 pg/ml; p = 0.005). Conclusion. Patients with RA had higher plasma sTREM-1 levels than healthy controls, and plasma sTREM-1 levels were correlated with disease activity measures, suggesting that plasma sTREM-1 could play a role in the inflammatory process associated with TNF-α, and that it may be a useful disease activity marker in RA.

Seasonality of Gout in Korea: A Multicenter Study

The object of this study was to evaluate the seasonality of gout in Korea. We retrospectively examined data from 330 patients seen at nine rheumatology clinics, treated with urate lowering therapy (ULT) more than one year after stopping prophylactic medication. Demographic data, clinical and laboratory features, and seasonality of gout onset and flares were collected. Season was classified in three-month intervals. The mean age was 52.2 yr and mean disease duration was 26.8 months. The male to female count was 318:12. The onset of acute gouty attacks was obtained in 256 patients. Gout developed most commonly in summer season (36.7%) (P<0.001) and in June (15.6%, P=0.002). During ULT, there were 147 (male 97.3%) gout flares. Although there was no statistically significant difference, gout flares were more common in summer (30.6%). Aggravating factors were identified in 57 flares: alcohol (72.0%) was most common. In the patients who attained target serum uric acid (<6 mg/dL) at the end of prophylaxis, gout flares were high in fall (35.8%) and September (17.0%). In Korea, the summer is most common season of gout onset and there is a tendency for gout flares to increase during ULT in summer/fall season. Graphical Abstract

Current gout treatment and flare in South Korea: Prophylactic duration associated with fewer gout flares

To evaluate treatment patterns and clinical factors affecting gout flare in South Korea.

Nonsteroidal antiinflammatory drugs (NSAID) versus NSAID with hydroxychloroquine in treatment of chemotherapy-related arthropathy: Open-label multicenter pilot study

To the Editor: Various musculoskeletal manifestations can develop in a patient receiving chemotherapy for malignancy1,2,3,4,5,6. We previously examined the occurrence and prognosis of chemotherapy-related arthropathy (CRA) in 18 patients with a variety of cancers with favorable responses after a mean of 3 months’ treatment with nonsteroidal antiinflammatory drugs (NSAID) and disease-modifying antirheumatic drugs (DMARD)7. However, that study was limited by the small number of enrolled patients and its retrospective design. Therefore, on the basis of our previous report, a multicenter randomized open-label pilot study was designed to evaluate whether adding hydroxychloroquine (HCQ) to NSAID modifies disease activity in CRA. Our study was conducted in accord with the ethical principles of the Declaration of Helsinki and was approved by the institutional review boards of the hospitals involved. We obtained written informed consent from all participants. We registered our trial in the database of the Clinical Research Information Service (http://ncrc.cdc.go.kr/cris: KCT0000160) as a randomized clinical trial (RCT). The open-labeled RCT was carried out at 7 tertiary hospitals from April 2007 to June … Address correspondence to Dr. C-H. Suh, Department of Rheumatology and BK21 Division of Cell Transformation and Restoration, Ajou University School of Medicine, San 5, Wonchon-dong, Yeongtong-gu, Suwon, South Korea 443-721. E-mail: chsuh{at}ajou.ac.kr