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Dive into the research topics where Myung Chul Yoo is active.

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Featured researches published by Myung Chul Yoo.


Arthritis Research & Therapy | 2009

Anti-inflammatory and antiarthritic effects of piperine in human interleukin 1β-stimulated fibroblast-like synoviocytes and in rat arthritis models

Jun Soo Bang; Da Hee Oh; Hyun Mi Choi; Bongjun Sur; Sung-Jig Lim; Jung Yeon Kim; Hyung-In Yang; Myung Chul Yoo; Dae-Hyun Hahm; Kyoung Soo Kim

IntroductionThe objective of this study was to determine the anti-inflammatory, nociceptive, and antiarthritic effects of piperine, the active phenolic component in black pepper extract.MethodsThe in vitro anti-inflammatory activity of piperine was tested on interleukin 1β (IL1β)-stimulated fibroblast-like synoviocytes derived form patients with rheumatoid arthritis. The levels of IL6, matrix metalloproteinase (MMPs), cyclo-oxygenase 2 (COX-2), and prostaglandin E2 (PGE2) were investigated by ELISA and RT-PCR analysis. The analgesic and antiarthritic activities of piperine were investigated on rat models of carrageenan-induced acute paw pain and arthritis. The former were evaluated with a paw pressure test, and the latter by measuring the squeaking score, paw volume, and weight distribution ratio. Piperine was administrated orally to rats at 20 and 100 mg/kg/day for 8 days.ResultsPiperine inhibited the expression of IL6 and MMP13 and reduced the production of PGE2 in a dose dependant manner at concentrations of 10 to 100 μg/ml. In particular, the production of PGE2 was significantly inhibited even at 10 μg/ml of piperine. Piperine inhibited the migration of activator protein 1 (AP-1), but not nuclear factor (NF)κB, into the nucleus in IL1β-treated synoviocytes. In rats, piperine significantly reduced nociceptive and arthritic symptoms at days 8 and 4, respectively. Histological staining showed that piperine significantly reduced the inflammatory area in the ankle joints.ConclusionsThese results suggest that piperine has anti-inflammatory, antinociceptive, and antiarthritic effects in an arthritis animal model. Thus, piperine should be further studied with regard to use either as a pharmaceutical or as a dietary supplement for the treatment of arthritis.


Arthritis Research & Therapy | 2009

Adiponectin may contribute to synovitis and joint destruction in rheumatoid arthritis by stimulating vascular endothelial growth factor, matrix metalloproteinase-1, and matrix metalloproteinase-13 expression in fibroblast-like synoviocytes more than proinflammatory mediators.

Hyun Mi Choi; Yeon Ah Lee; Sang-Hoon Lee; Seung Jae Hong; Dae Hyun Hahm; Sang Yun Choi; Hyung In Yang; Myung Chul Yoo; Kyoung Soo Kim

IntroductionThe role of adiponectin in the pathogenesis of arthritis is still controversial. This study was performed to examine whether adiponectin is involved in joint inflammation and destruction in rheumatoid arthritis (RA) in relation to the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs).MethodsSynovial cells from RA patients were treated with adiponectin or interleukin (IL)-1β for 24 hours. The culture supernatant was collected and analyzed for the levels of IL-6, IL-8, prostaglandin E2 (PGE2), VEGF, and MMPs by enzyme-linked immunosorbent assay. The levels of adiponectin, VEGF, MMP-1, and MMP-13 in the joint fluids from 30 RA or osteoarthritis (OA) patients were also measured.ResultsAdiponectin at the concentration of 10 μg/mL stimulated the production of IL-6, IL-8, and PGE2 in RA fibroblast-like synoviocytes (FLSs), although the level of these was much lower than with 1 ng/mL IL-1β. However, adiponectin stimulated the production of VEGF, MMP-1, and MMP-13 at the same level as IL-1β. In addition, the level of adiponectin and MMP-1 in the joint fluid of RA patients was significantly higher than in OA patients. Adiponectin was positively correlated with VEGF in RA patients but not in OA patients, while the level of MMPs in joint fluid was not correlated with adiponectin in either RA or OA patients.ConclusionsAdiponectin may play a significant role in the pathogenesis of RA by stimulating the production of VEGF and MMPs in FLSs, leading to joint inflammation and destruction, respectively.


Arthritis Research & Therapy | 2006

Association of the programmed cell death 1 (PDCD1) gene polymorphism with ankylosing spondylitis in the Korean population

Sanghoon Lee; Yeon-Ah Lee; Doo-Hyun Woo; Ran Song; Eun Kyung Park; Mi-Hyun Ryu; Younghoon Kim; Kyoung-Soo Kim; Seung-Jae Hong; Myung Chul Yoo; Hyung-In Yang

The PD-1 (programmed death 1) molecule is a negative regulator of T cells. PDCD1 (programmed cell death 1) has been reported to have a genetic association in systemic lupus erythematosus and rheumatoid arthritis in Caucasians. However, there are no reports on the association between this gene and ankylosing spondylitis (AS). The present study investigated the association of the PD-1 polymorphisms and the haplotypes with AS in a Korean population sample. In a case-control association study, two single-nucleotide polymorphisms, PD-1.5 C/T and PD-1.9 T/C, were genotyped in 95 AS patients and 130 healthy controls. The T allele of the PD-1.9 polymorphism was more frequent in the Korean male population with AS than in the Korean male controls (21.0% versus 6.9%, odds ratio 1.89, 95% confidence interval 1.483 to 2.408). The frequency of the CT haplotype (PD-1.5 C/T and PD-1.9 T/C) was higher in the AS patients (19%) than the controls (5.4%) (odds ratio 1.83, 95% confidence interval 1.559 to 2.521). The PD-1 polymorphism was demonstrated in Korean AS patients. The results suggest a genetic association between the PD-1 polymorphism and susceptibility to AS.


Rheumatology International | 2011

Expression levels and association of gelatinases MMP-2 and MMP-9 and collagenases MMP-1 and MMP-13 with VEGF in synovial fluid of patients with arthritis.

Kyoung Soo Kim; Hyun Mi Choi; Yeon-Ah Lee; In Ah Choi; Sang-Hoon Lee; Seung-Jae Hong; Hyung-In Yang; Myung Chul Yoo

This study was performed to provide evidence, albeit indirectly, as to which matrix metalloproteinases (MMPs), among the gelatinases MMP-2 and MMP-9 and the collagenases MMP-1 and MMP-13, play a more proactive role in the angiogenic process in arthritic joint. Joint fluid was collected from 33 patients with rhuematoid arthritis (RA) and osteoarthritis (OA), and protein (MMPs and vascular endothelial growth factor (VEGF)) levels were measured by ELISA, and the association of MMPs with VEGF was evaluated in joint fluid of patients with RA or OA. The levels of collagenases (total MMP-1 and total MMP-13) and gelatinases (total MMP-2 and total MMP-9) in RA joint fluid were significantly higher than those in OA fluid. Total MMP-9 levels were significantly associated with VEGF levels in RA fluids, but not in OA fluid, while total MMP-13 levels were strongly associated with VEGF levels in both RA and OA fluid. However, total MMP-2 and total MMP-1 levels were not associated with VEGF levels in either RA or OA joint fluid. Our results indirectly suggest that in RA and OA, MMP-9 and MMP-13 may play a more important role in angiogenesis than MMP-2 and MMP-1.


Drugs | 1997

NSAID-Induced Gastrointestinal Damage

G. David Champion; Pao Hsii Feng; Takeshi Azuma; David E. Caughey; Ka Ho Chan; Sadao Kashiwazaki; Hwa-Chang Liu; Achmad R. Nasution; Masasni Nobunaga; Surawut Prichanond; Tito P. Torralba; Visitsunthorn Udom; Deesomchok Utis; Soo Ray Wang; Woon Sing Wong; Dah-Jung Yang; Myung Chul Yoo

SummaryThe problem of nonsteroidal anti-inflammatory drug (NSAID)-induced gastrointestinal toxicity was reviewed by members of the Asia Pacific League of Associations for Rheumatology (APLAR) in a consensus conference in September 1992. This paper by the participants presents the consensus conclusions incorporating knowledge from recent publications. There had been a high level of concern that much of the toxicity had resulted from extensive and indiscriminate prescribing of NSAIDs. The implementation of evidence-based guidelines was considered likely to be able to effect a substantial reduction in toxicity without significant loss of overall therapeutic benefit. The evidence from which such guidelines could be developed is critically appraised.


Journal of Ethnopharmacology | 2010

The analgesic and anti-inflammatory effect of WIN-34B, a new herbal formula for osteoarthritis composed of Lonicera japonica Thunb and Anemarrhena asphodeloides BUNGE in vivo

Moonkyu Kang; In-Ho Jung; Jonghyun Hur; Soon Han Kim; Jeong Hun Lee; Ji-Yun Kang; Kyoung Chul Jung; Kyoung Soo Kim; Myung Chul Yoo; Dong-Suk Park; Jae-Dong Lee; Yong-Baik Cho

ETHNOPHARMACOLOGICAL RELEVANCE Lonicera japonica Thunb and Anemarrhena asphodeloides BUNGE have been used for the treatment of a variety of inflammatory diseases, cold and infective diseases in many countries, including Korea and China. AIM OF THE STUDY This study aimed to assess the anti-nociceptive and anti-inflammatory activities of n-butanol fraction (WIN-34B) prepared from dried flowers of Lonicera japonica and dried roots of Anemarrhena asphodeloides as potential novel treatment of osteoarthritis. MATERIALS AND METHODS Anti-nociceptive activities of WIN-34B (100, 200 and 400 mg/kg, p.o.) were measured using acetic acid-induced writhing response, formalin-induced paw licking, hot plate, radiant heat tail-flick, carrageenan-induced paw pressure, and Hargreaves tests, respectively. Anti-inflammatory activities of WIN-34B (100, 200 and 400 mg/kg, p.o.) were assessed using acetic acid-induced vascular permeability, carrageenan-induced paw edema, and croton oil-induced ear edema. Anti-osteoarthritis effect of WIN-34B was analyzed using monosodium iodoacetate (MIA)-induced osteoarthritis animal model. RESULTS WIN-34B exhibited better anti-inflammatory activity than that of celecoxib in carrageenan at the dose of 200 mg/kg and croton oil-induced paw edema and ear edema at the doses of 200 and 400 mg/kg. WIN-34B exhibited significant anti-inflammatory effects on vascular permeability. WIN-34B also exhibited significant anti-nociceptive activities in the late phase of formalin-induced paw licking and writhing response model in mice. In radiant heat tail-flick and carrageenan-induced paw pressure tests, WIN-34B at the dose of 400 mg/kg and at the doses of 200 and 400 mg/kg presented similar activities to indomethacin and celecoxib. Compared to indomethacin WIN-34B at 400mg/kg showed similar or better anti-nociceptive activities after 1 and 2h of theraphy in the hot plate test and better anti-nociceptive activity than that of celecoxib in Hargreves test. In the MIA-induced osteoarthritis animal models, WIN-34B at 400 mg/kg exhibited similar or better anti-nociceptive property than that of celecoxib throughout the pain measurement periods. CONCLUSION When compared to celecoxib, WIN-34B exhibited similar or better anti-nociceptive and anti-inflammatory activities in osteoarthritic animal models, which may become a potential novel treatment for osteoarthritis.


Clinical Rheumatology | 2007

Synovial proliferation differentially affects hypoxia in the joint cavities of rheumatoid arthritis and osteoarthritis patients

Yeon-Ah Lee; Jung Yeon Kim; Seung-Jae Hong; Sang-Hoon Lee; Myung Chul Yoo; Kyoung Soo Kim; Hyung-In Yang

This study was performed to investigate whether synovial proliferation (SP) differentially affects hypoxia in the joint cavities of rheumatoid arthritis (RA) and osteoarthritis (OA) patients. Thirty RA and 42 OA patients who underwent synovitis assessment were classified into two groups based on the presence or absence of SP, as revealed by musculoskeletal ultrasonography. Synovial fluids (SFs) from the knee joints were analyzed for interleukin (IL)-8, pO2, and white blood cell counts and blood samples were analyzed for erythrocyte sedimentation rate (ESR). No difference was found between the OA patients with and without SP in terms of SF oxygen tension (SF pO2) or IL-8 level, whereas the RA patients had significantly lower SF pO2 levels in their knee joints than did the OA patients with SP, and the RA patients had higher levels of IL-8 in their joints than did the OA patients. The counts of infiltrated immune cells in the SF and tissues were much higher for patients with RA and SP than for those with OA and SP. The ESRs were not found to be correlated with SP in OA patients but were negatively correlated with SF pO2 levels in RA patients. We conclude that ultrasonographically detected SP in OA patients does not generate a more hypoxic SF than that found in OA patients without SP. The SFs from RA patients with SP are hypoxic, which indicates that SP may have different impacts on hypoxia in the joint cavities of RA and OA patients.


Arthritis Research & Therapy | 2007

Taurine chloramine differentially inhibits matrix metalloproteinase 1 and 13 synthesis in interleukin-1β stimulated fibroblast-like synoviocytes

Kyoung Soo Kim; Eun-Kyung Park; Seung Min Ju; Hye-Sook Jung; Jun Soo Bang; Chaekyun Kim; Yeon-Ah Lee; Seung-Jae Hong; Sang-Hoon Lee; Hyung-In Yang; Myung Chul Yoo

It has been suggested that taurine chloramine (TauCl) plays an important role in the downregulation of proinflammatory mediators. However, little is known about its effect on the expression of matrix metalloproteinases (MMPs). In this study, we investigated the effects of TauCl on synovial expression of MMPs. The effects of TauCl on MMP expression in IL-1β stimulated fibroblast-like synoviocytes (FLSs) were studied using the following techniques. Real-time PCR and semi-quantitative PCR were employed to analyze the mRNA expression of MMPs. ELISA was used to determine protein levels of MMPs. Western blot analyses were performed to analyze the mitogen-activated protein kinase and inhibitor of nuclear factor-κB (IκB) kinase signalling pathways. Finally, electrophoretic mobility shift assay and immunohistochemistry were used to assess localization of transcription factors. IL-1β increased the transcriptional and translational levels of MMP-1 and MMP-13 in rheumatoid arthritis FLSs, whereas the levels of MMP-2 and MMP-9 were unaffected. TauCl at a concentration of 400 to 600 μmol/l greatly inhibited the transcriptional and translational expression of MMP-13, but the expression of MMP-1 was significantly inhibited at 800 μmol/l. At a concentration of 600 μmol/l, TauCl did not significantly inhibit phosphorylation of mitogen-activated protein kinase or IκB degradation in IL-1β stimulated rheumatoid arthritis FLSs. The degradation of IκB was significantly inhibited at a TauCl concentration of 800 μmol/l. The inhibitory effect of TauCl on IκB degradation was confirmed by electrophoretic mobility shift assay and immunochemical staining for localization of nuclear factor-κB. TauCl differentially inhibits the expression of MMP-1 and MMP-13, and inhibits expression of MMP-1 primarily through the inhibition of IκB degradation, whereas it inhibits expression of MMP-13 through signalling pathways other than the IκB pathway.


International Orthopaedics | 1998

A prospective randomized study on the use of nadroparin calcium in the prophylaxis of thromboembolism in Korean patients undergoing elective total hip replacement

Myung Chul Yoo; C. S. Kang; Young-Jae Kim; Seul-Ki Kim

Summary. Because of the belief that post-operative deep vein thrombosis (DVT) is rare in Asian patients, thromboprophylaxis is not usually prescribed for surgical patients. This study reports an open multi-centre controlled study of the use of a low molecular weight heparin, nadroparin calcium (Fraxoparine Sanofi France), as opposed to no prophylaxis in 100 patients undergoing uncemented total hip replacement. The patients had bilateral venography performed preoperatively and 10 days after operation. Eight patients (16%) developed DVT in the control group of 50 patients and 1 (2%) in the treatment group, also of 50 patients. Pulmonary embolus occurred in 1 patient in the treatment group and in 3 in the control group. Intraoperative and postoperative blood loss did not differ significantly between the two groups. Our study suggests that the incidence of DVT in Asian patients, though somewhat less than in their Western counterparts, is still considerable. It confirms the safety and efficacy of nadroparin calcium in preventing post-operative DVT in patients undergoing elective total hip replacement.Résumé. A cause de l’idée selon laquelle la thrombose veineuse profonde post-opéraloire est rare parmi les patients asiatiques, la tromboprophylaxie pour les patients opérés est inhabituelle. Nous avons accompli une étude, comparant la prophylaxie au moyen d’héparine de bas poids moléculaire en utilisant du calcium nadroparine (Fraxiparine Sanofi France) et la non-prophylaxie sur 100 patients subissant un remplacement total de la hanche. Les patients ont subi une vénographie bilatérale avant l’opération et 10 jours après. Huit patients (16%) ont développé une thrombose veineuse dans le groupe de contrôle, contre 1 (2%) dans le groupe traité (p = 0.015, 95% CI 0.02 – 0.67). Trois embolies pulmonaires sont survenues dans le groupe de contrôle et 1 dans le groupe traité (p = 0.27 95% CI 0.04 – 2.44) aucune n’étant fatale. La perte de sang intra-opératoire et post-opératoire n’a pas varié de manière significative entre les deux groupes. Notre étude démontre que l’incidence de la thrombose veineuse profonde post-opératoire chez les patients asiatiques est notable bien qu’elle soit moindre que dans les pays occidentaux et confirme la sûreté et l’efficacité du calcium nadroparine pour la prévenir aprés un remplacement total de la hanche.


Journal of Arthroplasty | 2011

Causes and Patterns of Aborting a Robot-Assisted Arthroplasty

Young Soo Chun; Kang Il Kim; Yoon Je Cho; Yoon Hyuk Kim; Myung Chul Yoo; Kee Hyung Rhyu

For a successful robot-assisted arthroplasty, every step should be executed harmoniously. However, when we encounter serious obstacles during surgery, it is sometimes better to abort the procedure in a timely manner. This study investigated the possible causes and patterns of aborted robot-assisted arthroplasties. Of 100 consecutively planned robot-assisted arthroplasties, 22 cases were aborted. Most involved total knee arthroplasty (21/22 cases). We classified the causes according to the stage at which they occurred and the type of error. Abortions after starting the milling procedure and abortions due to an interactive factor were the most common. We believe that this study can guide surgeons to effective decision making during robot-assisted arthroplasty.

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