EGCG对中波紫外线诱导HaCaT细胞p53基因和蛋白表达的实验研究

目的:研究表没食子儿茶素没食子酸酯(EGCG)对中波紫外线(UVB)照射诱导永生化角质形成细胞株-HaCaT细胞的p53 mRNA和p53蛋白表达的影响。方法:以一定剂量UVB照射HaCaT细胞,并以200μg/mL EGCG处理照射后的HaCaT细胞,分别用RT-PCR法和Western blot方法检测各处理条件下p53 mRNA和/或p53蛋白的表达水平。结果:30 mJ/cm2的UVB照射后HaCaT细胞的p53 mR-NA和p53蛋白表达逐渐增加,4 h达到峰值,4 h后随照射剂量增加而增加,24 h后有所恢复;加入EGCG可下调UVB诱导的表达作用。结论:UVB照射对HaCaT细胞p53 mRNA和p53蛋白的诱导表达有时效性与量效性,EGCG可下调UVB照射的这种诱导作用。     

表没食子儿茶素没食子酸酯对中波紫外线诱导人原代表皮黑素细胞光损伤干预作用的研究

目的:观察中波紫外线(UVB)诱导人原代表皮黑素细胞光产物的形成和清除情况,以及表没食子儿茶素没食子酸酯(EGCG)的干预作用.方法:选择10、20、40、80、100 mg/L 5种浓度EGCG作用于体外培养的人表皮黑素细胞72 h,测定细胞增殖活性.采用免疫斑点印迹技术在30 mJ/cm2UVB照射及EGCG干预下.分别取照射后0.5 h和24 h检测环丁烷嘧啶二聚体(CPDs)的产生和清除量.结果:低浓度(＜20 mg/L)EGCG能促进黑素细胞增殖.UVB照射后黑素细胞内光产物形成较快,但清除缓慢.EGCG对UVB诱导光产物的形成无明显影响,但能加速光产物的清除(P＜0.05).结论:EGCG能加速UVB照射后黑素细胞内光产物的清除.     

中波紫外线对角质形成细胞MMP-1及TIMP-1的影响

目的：研究中波紫外线照射对永生化人角质形成细胞的影响。方法：绘制细胞生长曲线,用不同剂量UVB（30、60、90 mJ/cm2）照射永生化人角质形成细胞,用MTT方法测定UVB照射后细胞的增殖活性,用RT-PCR方法测定HaCaT细胞中MMP-1mRNA和TIMP-1mRNA的表达。结果：UVB照射后,HaCaT细胞的增殖活性受到抑制,MMP-1 mRNA表达增强,TIMP-1 mRNA表达下降,90 mJ/cm2照光组与未照光组比较,差异均有统计学意义。结论：UVB照射可诱导HaCaT细胞损伤和细胞凋亡,促使MMP-1mRNA表达增加,TIMP-1 mRNA表达减少,二者比例失调,这可能与光老化的发生有一定的关系。     

APP17肽对紫外线照射的皮肤成纤维细胞MMP-1和TIMP-1 mRNA表达的影响

目的:探讨β-淀粉样前体蛋白17肽(APP17肽)对紫外线照射后人皮肤成纤维细胞增殖及MMP-1和TIMP-1mRNA表达的影响。方法:在培养的人皮肤成纤维细胞中加入不同浓度的APP17肽,并用UV照射培养的人皮肤成纤维细胞。MTT法检测细胞活性,应用RT-PCR方法检测不同剂量APP17肽及UV照射后细胞中MMP-1mRNA和TIMP-1mRNA的表达情况。结果:APP17肽可增加非照射及UV照射后成纤维细胞的活性(P<0.05)。RT-PCR结果显示,6J/cm2UVA 36mJ/cm2UVB照射后MMP-1mRNA的表达增加1.78倍(P<0.01),TIMP-1mRNA的表达增加1.13倍(P<0.05)。APP17肽可在一定水平抑制MMP-1mRNA的表达,并诱导TIMP-1mRNA的表达(P<0.05)。结论:APP17肽可抑制体外培养的成纤维细胞的胶原降解,并可抑制UV诱导的胶原降解。     

UVB致成纤维细胞损伤及两种中药的保护作用研究

目的观察中波紫外线(UVB)辐射后成纤维细胞(FB)DNA光产物环丁烷嘧啶二聚体(CPD s)产生和清除情况及表没食子儿茶素没食子酸酯(EGCG)和黄芩甙的干预作用。方法以30,60,90 m J/cm2UVB照射FB并予EGCG及黄芩甙干预处理,采用免疫细胞化学法在照光后不同时间检测CPD s的产生和清除情况。结果细胞损伤程度随照光剂量加大而加重;30 m J/cm2UVB照射后细胞CPD s生成量在辐射后1 h左右达到高峰,同时细胞也开始清除CP-D s,辐射后4 h内清除速率较快,4 h后清除速率逐渐降低,至24 h基本清除CPD s;EGCG和黄芩甙处理UVB辐射的细胞CPD s少于单纯照光组(P<0.05)。结论UVB辐射可以导致FB的DNA损伤而产生光产物CPD s;细胞损伤程度显示剂量依赖性;细胞自身有修复能力;EGCG和黄芩甙均可降低UVB辐射所致的光产物水平。     

表没食子儿茶素没食子酸酯对紫外线诱导的角质形成细胞分泌血管内皮生长因子的影响

目的：研究绿茶中表没食子儿茶素没食子酸酯（EGCG）对中波紫外线（UVB）诱导角质形成细胞HaCaT株（简称HaCaT细胞）分泌血管内皮生长因子（VEGF）的影响。方法：试验共设立空白对照组、单纯加药组、单纯照光组和加药照光组4组，以15mJ/cm^2 UVB的剂量照射细胞，酶联免疫吸附试验（EUSA）方法检测不同时间细胞上清液中VEGF含量。反转录（RT）-PCR测定VEGFmRNA表达。结果：UVB照射后，HaCaT细胞分泌的VEGF在照光后12h开始明显增加，随时间延长。VEGF水平逐渐增加。EGCG对UVB诱导的VEGF升高有明显抑制作用。在12、18、24h3个时间点．EGCG明显抑制VEGF水平的升高。结论：EGCG可以抑制紫外线诱导的HaCaT细胞分泌VEGF。     

甘草等提取物对UVB诱导小鼠皮肤HSP27基因表达的影响

目的:评价甘草、红景天、黄芪提取物对中波紫外线(UVB)照射诱导BALB/c小鼠皮肤HSP27mRNA表达水平的影响。方法:分组将自制5%与10%甘草、红景天、黄芪提取物溶液涂于小鼠背部皮肤,20min后给予500mJ/cm^2 UVB照射,每日1次,连续30天;设UVB对照组与空白对照组。RTPCR法检测各组小鼠背部皮肤组织中HSP27 mRNA的表达水平。结果:UVB照射组小鼠皮肤中HSP27 mRNA表达水平较空白对照组显著增高(P<0.05),不同剂量甘草、红景天、黄芪处理后可进一步上调HSP27表达水平(P<0.05)。结论:UVB照射可诱导小鼠皮肤HSP27 mRNA表达增加,甘草、红景天、黄芪可进一步诱导HSP27 mRNA表达增加。     

紫外线诱导HaCat转铁蛋白受体表达机制的初步探讨

目的探讨紫外线诱导转铁蛋白受体(TFR)表达的机制。方法以紫外线(UVB)照射HaCat,流式细胞仪检测TFR的表达,realtime-PCR检测TFRmRNA表达。结果UVB可增强TFR的表达,并呈剂量依赖性和时间依赖性。10mJ/cm2的UVB就能促进TFR表达,在紫外线照射后6h开始表达。UVB以剂量依赖性方式诱导TFR的mRNA表达,在UVB照射后8h,TFRmRNA表达水平达高峰,16h开始下降。结论UVB可增强TFR的表达。     

308 nm单频准分子光对人黑素细胞凋亡、周期和KIT蛋白表达的影响

目的 探讨308 nm单频准分子光对体外培养的人黑素细胞凋亡、细胞周期和KIT蛋白表达的影响.方法 在流式细胞仪上采用Annexin V检测0,20,40,80,160,300 mJ/cm2剂量308 nm单频准分子光照射后24 h黑素细胞的凋亡;采用碘化丙啶检测80 mJ/cm.照射后24 h细胞周期的变化.实时荧光PCR和Werstern印迹分别检测0,20,40,80,160,300 mJ/cm2剂量照射后24 h黑素细胞c-kit mRNA和KIT蛋白的表达.结果 照射后24 h,在小于160 mJ/cm2剂量下,黑素细胞凋亡无明显增加,但300 mJ/cm2时的凋亡率与对照相比较明显增加(P＜0.05).80 mJ/cm2剂量照射后24 h,S期细胞数明显高于其对照,分别为29.06%±0.75%和22.64%4±0.07%;低剂量308 nm单频准分子光照射后24 h,c-kit mRNA表达呈先增加后减少的趋势,80 mJ/cm2时达高峰,KIT蛋白的表达与mRNA的表达趋势一致.结论 低剂量308 nm单频准分子光(80 mJ/cm2)促进黑素细胞增殖和KIT的表达.     

双氢青蒿素对UVB诱导的人皮肤HaCaT细胞凋亡的保护作用

目的:明确双氢青蒿素(DHA)对UVB诱导人皮肤HaCaT细胞凋亡的保护作用。方法:将体外培养的HaCaT细胞分为空白对照组,UVB照射组和UVB+DHA(20、40、60、80μmol/L)组,采用MTT法检测细胞系的增殖情况,流式细胞仪检测细胞的凋亡率,RT-PCR法检测抗凋亡基因survivin和促凋亡基因caspease-3(激活型)mRNA水平,Western检测相关蛋白表达水平。结果:30 mJ/cm~2 UVB照射24 h后,UVB组和UVB+DHA(20、40、60、80μmol/L)组细胞的增殖率分别为空白对照组的(50.13±2.42)%,(60.23±2.30)%,(69.24±3.19)%,(79.37±2.47)%和(70.41±2.24)%。UVB组和UVB+60μmol/L DHA组中HaCaT细胞凋亡率分别为(46.7±3.2)%和(23.71±1.2)%。与UVB组比较,UVB+60μmol/L DHA组中HaCaT细胞caspase-3 mRNA及蛋白表达降低、survivin mRNA及蛋白表达升高。结论:DHA可抑制UVB所致HaCaT细胞的凋亡,其机制可能与survivin和caspase-3有关。     

Idiopathic calcinosis of the areola of the nipple

Idiopathic calcinosis cutis involving the breast is a rare condition. Previously reported cases were detected by mammography without specific cutaneous findings. We report a case of idiopathic calcinosis of the areola of the nipple in a 32-year-old Korean woman that has unique clinical features resembling scrotal calcinosis.     

自体疣包埋治疗尖锐湿疣疗效的Meta分析

目的：评价自体疣包埋对尖锐湿疣的治疗效果。方法：在Pubmed、《中国学术期刊网络出版总库》、《万方数据库》、《中文科技期刊数据库》中检索符合标准的关于自体疣包埋治疗尖锐湿疣的随机对照试验,应用Review Manager 5.3.5软件进行Meta分析。结果：共纳入10篇文献,入选文献发表偏倚较小,无明显异质性（P=0.25）。Meta分析结果显示,自体疣包埋联合CO2激光治疗对尖锐湿疣的治愈率显著高于单用CO2激光治疗,差异有统计学意义[Z=9.54,P<0.00001, RR=1.50,95%CI (1.38-1.63)]。结论：自体疣包埋联合CO2激光治疗治疗尖锐湿疣疗效优于单用CO2激光治疗。     

Functional properties of the surface of the vermilion border of the lips are distinct from those of the facial skin

BACKGROUND: The vermilion border of the lips (lip for short) is the only part on the face where the oral mucosa is persistently exposed to the outside. Despite its prominent presence on the face, constituting not only the target of cosmetics but also the site for various skin diseases, its functional properties remain almost unknown. OBJECTIVES: To elucidate the functional properties of the vermilion border of the lips. METHODS: We studied the biophysical properties of the lip by comparing them with those of the cheek skin in 303 healthy Japanese females aged 21-80 years, in winter. We used a closed-chamber system to measure transepithelial water loss (TEWL) of the lip to avoid the effect of breathing. Moreover, we examined the effects of oral etretinate, a drug that definitely produces dry, scaly lips, on the lips of seven male patients aged 49-89 (average 67) years. RESULTS: TEWL was significantly almost three times as high on the lips as that on the cheek which is a site that shows far higher levels than do other body areas. TEWL decreased with age more remarkably on the lip than on the cheek. High-frequency conductance, a parameter for surface hydration state, was significantly lower on the lip than on the cheek. The mean values obtained were about one-third of those on the cheek, and no age-related changes were observed either on the lip or on the cheek. The superficial epithelial cells on the lip were parakeratotic and larger than those of the cheek skin. Furthermore, we detected a significant increase in TEWL on the lip as well as on the cheek of patients treated with oral etretinate. CONCLUSIONS: It appears that the incomplete corneocyte formation of the lip surface is responsible for the poor barrier function and water-holding capacity.     

Measurement of the mechanical properties of the skin using the suction test

INTRODUCTION: The suction test is commonly used to study the mechanical properties of human skin in vivo. The unevenness of the stress fields complicates obtaining the intrinsic mechanical parameters of the skin in vivo because the values of the local stresses and deformations cannot be calculated directly from the displacements and forces applied by the test apparatus. In general, users only take into account the negative pressure applied and the elevation of the dome of skin drawn up in order to deduce the properties of the skin. This method has the major disadvantage of being dependent on the experimental conditions used: in particular, the size of the suction cup and the negative pressure applied. Here, we propose a full mechanical study of the test to provide rigorous results. We compare the frequently used geometric method (making the thin plate hypothesis), Timoshenko's method (which can take greater plate thicknesses into account) and finally various results obtained by the finite elements (FE) technique. METHODS: The suction test was modelled by FE with large displacements and large deformations both for orthotropic and isotropic plates. The results obtained in the elastic domain for various values of Young's modulus and of applied negative pressure were used as references and were compared with methods using analytical relationships. RESULTS: The geometric method generally used in the interpretation of suction tests gives results, which in certain configurations, are very different from those obtained by FE. The method of Timoshenko is suited to thick plates 'in contact' or embedded round the edge, the elevation of the dome and the tension and flexion stresss are analytically accessible through relationships involving four constants that are dependent on the limit conditions. Comparison with the FE results enabled the optimisation of the coefficients to adapt the relationships to the particular conditions of the suction trials. CONCLUSION: We showed the limits of the geometrical method and proposed a solution, which while remaining simple to use, gives results that are closer to reality both for the calculation of the modulus and for the determination of the state of the stresses obtained.