무모쥐에서 자외선에 의한 피부 장벽 손상에 미치는 커큐민의 보호 효과

전희영(Hee Young Jeon),김정기(Jeong Kee Kim),김완기(Wan Gi Kim),이상준(Sang Jun Lee) 한국식품과학회 2008 한국식품과학회지 Vol.40 No.6

In vivo에서 8주간의 UVB 처리에 의해 유발되는 피부 장벽 기능 손상에 대한 커큐민의 보호 효능을 관찰한 결과, UVB에 의해 유도되는 경표피 수분손실량의 증가와 비정상적인 각질 세포의 증식이 커큐민의 섭취에 의해 억제됨을 확인하여 커큐민이 피부 장벽 손상을 방어하고 피부 장벽 기능이 정상적으로 작용할 수 있도록 도움을 주는 것을 알 수 있었다. 커큐민의 피부 장벽기능 보호 작용 기전을 살펴보기 위하여 각질형성세포주를 이용하여 피부 장벽 조절인자에 대한 커큐민의 작용을 평가한 결과 커큐민은 filaggrin과 SPT의 발현을 농도 의존적으로 증가시킴을 확인하였으며, 이를 통하여 커큐민이 각질형성세포의 정상적인 분화를 촉진하고 세라마이드 합성에 영향을 미침으로써 피부 장벽 기능을 강화하는 효능이 있음을 추정할 수 있었다. 이상의 결과로부터 커큐민이 피부 장벽 보호 또는 개선 효능을 갖는 새로운 미용 식품 소재로써 이용 가능성이 높음을 알 수 있다. 다만 식품 소재로써 커큐민을 활용하기 위해서는 그간 보고된 커큐민의 낮은 bioavailability에 대한 연구를 참고하여 임상에서 유효한 용량을 설정하기 위한 연구가 더 이루어져야 할 것이다. Recent research has shown that curcumin has beneficial effects in a variety of skin diseases, including scleroderma, psoriasis, and skin cancer. In this study, we assessed the effects of curcumin on epidermal permeability barrier function in vivo and in vitro. In order to evaluate the effects of curcumin on epidermal permeability barrier function in vivo, hairless rats were exposed to UVB irradiation, and curcumin was administered orally at a dosage of 150 ㎎/㎏ per day for 8 weeks. Transepidermal water loss (TEWL) and epidermal thickness were measured at the end of the experiment. The expression of filaggrin, a marker of keratinocyte differentiation, and serine palmitoyltransferase (SPT), a marker of the formation of the stratum corneum lipid barrier, in human HaCat keratinocytes were analyzed. The in vivo results showed that an 8 week administration of curcumin markedly prevented the UVB-induced increase in TEWL. The UV-induced increase in epidermal thickness was also reduced significantly by curcumin treatment. The in vitro results demonstrated the concentration-dependent effects of curcumin on the expression of both filaggrin and SPT in HaCat cells, reflecting the notion that curcumin can induce epidermal keratinocyte differentiation and can improve the recovery of skin barrier functions. These results show that curcumin is a promising candidate for the improvement of epidermal permeability barrier function.

에폭시 수지의 경화 거동에 미치는 반응성 희석제의 영향

김완영,이대수,김형순,김정기 ( Wan Young Kim,Dai Soo Lee,Hyung Soon Kim,Jung Gee Kim ) 한국공업화학회 1994 공업화학 Vol.5 No.6

에폭시 수지의 성형 가공성을 조절하기 위해 반응성 희석제를 사용했을 때의 경화특성 및 경화 후 유리 전이온도의 변화를 조사하였다. 반응성 희석제로 사용한 Butyl gilcidyl ether(BGE) 및 Phenyl glycidyl ether(PGE)함량의 증가에 따라 경화에 따른 발열량과 경화 후 유리 전이온도는 낮아지는 특성이 관찰되었다. 에폭시 수지는 BGE를 사용한 경우 PGE를 사용한 경우보다 더 낮은 유리 전이온도를 보였으며, 희석제의 첨가에 따른 유리 전이온도 변화는 가교점 사이의 분자량 증가 때문으로 해석하였다. 에폭시 수지의 경화 거동을 자촉매 반응에 대한 속도론식으로 해석한 결과 속도상수 k₁, k₂는 희석제의 양에 따라 감소하였다. Curing behavior and glass transition temperatures of epoxy resins into which reactive diluents were added to control processability were investigated. Heat of cure generated of the epoxy resin was reduced with butyl glycidyl ether(BGE) and phenyl glycidyl ether(PGE) contents. T_g of the resin was decreased with the amount of reactive diluents and it was attributed to increased molecular weight between crosslink points. Cure kinetics of the resins was studied employing autocatalytic reaction model and found that reaction constants decreased as the contents of reactive diluent was increased.

만성 신부전 환자에서 과호모시스테인혈증의 유병율 및 그 결정 인자

최원,김정기,박미정,박병석,나명윤,염충호,김수완,최기철,강영준 대한신장학회 2000 대한신장학회잡지 Vol.19 No.6

혈액투석 환자에서 혈청 마그네슘과 부갑상선호르몬 치의 관계

마성권,김정기,박미정,박병석,나명윤,염충호,김수완,김남호,강영준,최기철 대한신장학회 2000 대한신장학회잡지 Vol.19 No.6

지속성 외래 복막투석 환자에서 Erythropoietin 치료의 반응감소 예측인자

박미정,김정기,김남호,최원,최기철,박병석,이성철,강영준,김수완,마성권,정권 대한내과학회 2000 대한내과학회지 Vol.59 No.2

Background : The present study was aimed at investigating the predictive parameters of erythropoietin (EPO) hyporesponsiveness in patients with continuous ambulatory peritoneal dialysis (CAPD). Methods : We studied 40 patients with end stage renal failure who were receiving peritoneal dialyis for at least 6 months and EPO therapy for at least more than 2 months. Pearson's simple correlation and multiple stepwise linear regression analysis was used to discover what parameter can predict EPO resistance. We expressed EPO resistance index (ERI) as 'weekly EPO dose/hematocrit/body weight'. The dose of EPO is titrated by about 25% every 2 or 4 weeks to maintain a target hematocrit between 33% and 36%. Results : We analyzed the relationship between ERI and other predictive parameters by Pearson's correlation. These results showed ERI has a statistically significant correlation with transferrin saturation (TS) (r=-0.327, p=0.042), total Kt/V (r=-0.423, p=0.018), serum albumin (r=-0.458, p=0.003), normalized protein catabolic rate (nPCR) (r=-0.479, p=0.006), normalized protein equivalent of total nitrogen appearance (nPNA) (r=-0.488, p=0.005) and serum C-reactive protein (CRP) (r=0.332, p=0.036). Regression analysis was performed using stepwise linear regression for multiple variables to discover the most independent variable which is correlated with ERI. ERI was entered as a dependent variable, whereas the other parameters (age, duration of peritoneal dialysis, serum albumin, CRP, serum ferritin, total Kt/V, nPCR, nPNA, serum iPTH, serum aluminium, TS) were entered as independent variables. This analysis showed CRP was the most significant variable, and if CRP is excluded, nPNA was the significant variable. CRP had a statistically significant correlation with serum albumin (r=-0.418, p=0.007) and total Kt/V (r=-0.366, p=0.043). High CRP group had more increased level of ERI(p$lt;0.05), age(p$lt;0.05) and serum creatinine(p$lt;0.05) than normal control, but more decreased level of serum albumin(p$lt;0.01) and serum iron level(p$lt;0.05). Conclusion : These results indicate that CRP is the most important predictor of EPO hyporesponsiveness.(Korean J Med 59:183-191, 2000)

만성 신부전 환자에서 과호모시스테인혈증의 유병율 및 그 결정 인자

박미정,최원,강영준,김정기,박병석,김수완,나명윤,염충호,최기철 대한신장학회 2000 Kidney Research and Clinical Practice Vol.19 No.6

Background: Hyperhomocysteinemia plays an important role in atherosclerosis resulting from endothelial dysfunction and injury followed by platelet activation and thrombus formation. We evaluated the prevalence and determinants of hyperhomocysteinemia in patients with chronic renal failure(CRF) and relationship between hyperhomocysteinemia and cardiovascular diseases. Methods: We evaluated the prevalence of hyperhomocysteinemia in CRF patients and hemodialysis patients. Fasting plasma homocysteine, vitamin B12, vitamin B6 creatinine, fibrinogen, lipoprotein(a), glucose, total cholesterol, HDL cholesterol, and TG levels were assessed in 69 patients. Results: Hyperhomocysteinemia was detected 5% in controls, 86% in CRF groups, and 85% in hemodialysis group. Serum folate value in hemodialysis group was significantly higher than normal control (10.7±4.8 vs. 15.3±5.4nmoL/L; p$lt;0.05). Plasma homocysteine concentration negatively correlated with serum folate level in hemodialysis patients(r=-0.42, p$lt;0.05). Cardiovaslar diseases were deteceted 14% in CRF patients and 25% in hemodialysis patients. Matched odds ratios(with 95% confidence intervals) were respectively 118.75, 107.7 for homocysteine in CRF and hemodialysis patients compaired with control group. Conclusion: Plasma homocysteine level correlated negatively with serum folate level in hemodialysis patients. In univariate analysis, determinant of plasma homocysteine concentration in hemodialysis patients is plasma folate concentration. We considered that hyperhornocysteinemia is also an independent risk factor of cardiovascular diseases.

혈액투석 환자에서 혈청 마그네슘과 부갑상선호르몬 치의 관계

박미정,김남호,강영준,김정기,박병석,김수완,나명윤,마성권,염충호,최기철 대한신장학회 2000 Kidney Research and Clinical Practice Vol.19 No.6

The important factors involved in the regulation of PTH are calcium, vitamin D, and phosphorus. However, recent studies have suggested that magnesium may also play a significant role in the modulation of PTH. The aims of this study was to analyze the relationship between serum magnesium and PTH levels in the hemodialysis patients. We studied 66 stable patients under maintenance hemodialysis for more than 6 months. Calcium carbonate was used as a phosphate binder in all patients. No patient had been previously treated with vitamin D and aluminum hydroxide. Biochemical parameters were evaluated 3 times during 7 months, and the mean values were computed. The mean serum magnesium level was 2.7±0.4 mEq/L. Hypermagnesemia(defined as serum Mg$gt;2.2 mEq/L) was found in 60 patients(90.1%). Serum magnesiurn levels were inversely correlated with senum iPTH levels(r=-0.579; p$lt;0.001). Serum total and ionized calcium levels were inversely correlated with serum iPTH levels(r=-0.743; p$lt;0.001, r=-0.699; p$lt;0.001, respectively).Serum alkaline phosphatase levels positively correlated with serum iPTH levels (r=0.364; p=0.003). In lower iPTH group(serum iPTH120pg/mL), serum magnesium, total calcium, and ionized calcium levels were significantly higher. Alkaline phosphatase level was significantly lower in lower PTH group. After controlling for the effect of the other variables, serum magnesium and iPTH levels were inversely correlated(r=-0.53; p$lt;0.001). A stepwise multiple regression analysis showed that serum magnesium level was the most predictive variable(R²=0.72; p$lt;0.001). Hypermagnesemia is frequent in hemodialysis patients. There is a significant inverse relationship between serum magnesium and PTH levels. In addition, serum magnesium concentration has an important influence on PTH regulation. These results suggest that hypermagnesemia may have a suppressive effect on PTH regulation in hemodialysis patients.