重楼皂苷Ⅰ通过抑制PI3K/Akt/mTOR通路诱导人黑素瘤A375细胞凋亡与自噬

目的探讨重楼皂苷Ⅰ(PolyphylinⅠ,PPⅠ)对人黑素瘤A375细胞凋亡和自噬的影响以及相关机制,确定PPⅠ诱导的细胞自噬与其促进A375细胞凋亡的相关性。方法 PPⅠ处理A375细胞后,采用CCK-8法检测细胞活力;Annexin V-FITC/PI双标法检测PPⅠ对人黑素瘤细胞凋亡的作用;免疫印迹法检测相关蛋白的表达水平;通过观察细胞内自噬标志分子LC3的分布与表达来确定PPⅠ对自噬的诱导作用;采用氯喹抑制细胞自噬后,观察PPⅠ对细胞凋亡的影响。结果 PPⅠ能抑制A375细胞增殖活力;PPⅠ抑制PI3K/Akt/mTOR通路的活化并促进了A375细胞内Bax和cleaved-caspase 3的表达,抑制Bcl-2表达,诱导人黑素瘤细胞发生凋亡;PPⅠ促进了A375细胞LC-Ⅱ/LC-Ⅰ值和Beclin-1蛋白表达的升高,下调了p62蛋白的水平,促进了细胞自噬;PI3K/Akt/mTOR通路活化剂IGF-1处理A375细胞后抑制了PPⅠ的上述作用;PPⅠ与自噬抑制剂氯喹联用后,A375细胞凋亡数量明显减弱。结论 PPⅠ能抑制A375细胞的增殖,诱导细胞发生凋亡与自噬,抑制自噬减少了PPⅠ诱导的人黑素瘤细胞凋亡。     

Celecoxib抑制人黑素瘤A375细胞增殖及对Cox-2/MMP-1蛋白表达的影响

目的研究Celecoxib(塞来考昔)对人黑素瘤A375细胞增殖抑制、凋亡诱导和周期阻滞作用及对A375细胞表达Cox-2和分泌型MMP-1蛋白的影响。方法MTT法测定Celecoxib对A375细胞的增殖抑制作用,流式细胞术检测药物诱导细胞凋亡及周期阻滞作用;细胞爬片SABC免疫细胞化学检测Celecoxib对A375细胞Cox-2蛋白表达的影响,ELISA法分析Celecoxib对A375细胞分泌型MMP-1蛋白表达的影响。结果80μmol/L的Celecoxib明显抑制人黑素瘤A375细胞增殖,并诱导凋亡(凋亡率35.91%)和G2/M期阻滞,减少A375细胞表达Cox-2蛋白和分泌型MMP-1蛋白。结论人黑素瘤A375细胞表达Cox-2蛋白和MMP-1蛋白,Celecoxib是一种有潜力的抑制黑素瘤增殖的药物。     

重楼皂苷Ⅱ对A375人黑素瘤细胞增殖和凋亡的影响

目的研究重楼提取物单体重楼皂苷Ⅱ在体外对A375人黑素瘤细胞增殖和凋亡的影响。方法体外培养A375人黑素瘤细胞株,采用MTT法检测重楼皂苷Ⅱ对细胞增殖的影响,计算IC50值;透射电镜观察细胞超微结构的变化;采用流式细胞术检测重楼皂苷Ⅱ干预后A375人黑素瘤细胞凋亡的情况。结果重楼皂苷Ⅱ对A375人黑素瘤细胞的增殖有明显的抑制作用,24h的IC50值为12.04μmol/L。重楼皂苷Ⅱ对人A375细胞生长的抑制作用表现出时间和浓度依赖性。另外重楼皂苷Ⅱ引起A375黑素瘤细胞的凋亡率显著增加。结论重楼皂苷Ⅱ对A375人黑素瘤有潜在的抗癌作用,可能是通过诱导黑素瘤细胞凋亡而发挥作用。     

芍药苷对人黑素瘤细胞株A375增殖凋亡的影响

目的:研究不同浓度芍药苷(PF)对人黑素瘤细胞A375增殖抑制及早期凋亡的影响.方法:将体外培养的人黑素瘤细胞株A375分为6组,5个实验组分别加入不同浓度PF(2、1、0.5、0.1、0.01 mg/mL),对照组不加PF.光镜下观察细胞密度及形态、MTT法测定细胞增殖抑制率,Amnexin V/PI染色法检测细胞早期凋亡率.结果:镜下观察可见随着PF浓度的增加,黑素瘤细胞株A375数量降低,贴壁能力渐差,细胞形态渐圆钝,甚至出现皱缩.与对照组相比,不同浓度PF处理A375细胞24h、48h和72 h后,PF对细胞有浓度依赖性的增殖抑制作用(P＜0.05),但未见明显的时间依赖性(P＞0.05).不同浓度PF干预24h时A375细胞的早期凋亡率,对照组和各实验组差异无统计学意义(P＜0.05).结论:PF能抑制人黑素瘤细胞株A375的增殖,这种抑制作用呈浓度依赖性而非时间依赖性,但对A375细胞早期凋亡率无明显影响.     

白藜芦醇对恶性黑素瘤细胞株增殖的影响

目的 研究白藜芦醇对恶性黑素瘤体外抗癌作用,探讨其抗癌作用的分子机制.方法 采用MTT法检测白藜芦醇对人恶性黑素瘤细胞系A375及小鼠恶性黑素瘤细胞系B16-F1增殖的影响;Annexin-V/PI双标流式细胞术检测白藜芦醇对A375、B16-F1细胞凋亡的影响,PI单标流式细胞术测定白藜芦醇对A375、B16-F1细胞周期的影响;Western印迹法检测白藜芦醇对A375、B16-F1细胞Bcl-2、Bax蛋白表达的影响.结果 白藜芦醇对A375、B16-F1细胞增殖具有明显的抑制作用,且呈量效及时效关系.25 μmol/L白藜芦醇作用24 h即可诱导A375细胞凋亡,其细胞凋亡率为16.7%±2.1%.100μmol/L白藜芦醇作用24 h时B16-F1细胞凋亡率可达39.6%±3.3%.100 μmol/L白藜芦醇作用12 h时A375细胞凋亡率为17.2%±1.7%,作用72 h时达52.3%±4.1%;相同浓度白藜芦醇作用12 h时B16-F1细胞凋亡率为18.4%±1.6%,作用72 h时达56.7%±4.5%.白藜芦醇处理组A375及B16-F1细胞周期均发生变化,细胞周期被阻滞于G1期,此阻滞效应随白藜芦醇浓度的增加而增加,25 μmol/L、100μmol/L白藜芦醇作用24 h时,A375 G1期比例分别为40.51%±3.97%和55.64%±4.95%.B16-F1细胞分别为41.34%±3.12%和53.93%±5.12%.白藜芦醇明显下调A375及B16-F1细胞抗凋亡蛋白Bcl-2的表达,同时上调促凋亡蛋白Bax的表达水平.结论 白藜芦醇可通过调控细胞周期进程、诱导细胞凋亡而有效抑制A375及B16-F1的增殖,其机制与调节Bel-2、Bax的表达有关.     

维A酸CD437和阿维A抑制人黑素瘤A375细胞的比较

目的探讨合成的维A酸CD437与阿维A对体外培养的人黑素瘤A375细胞的增殖抑制、凋亡诱导、周期阻滞作用及对Bax/bcl-2蛋白表达的影响。方法MTT法测定CD437及阿维A对人黑素瘤A375细胞的增殖抑制作用;流式细胞术检测两种药物诱导细胞凋亡及周期阻滞;细胞爬片SABC免疫细胞化学分析两种药物对细胞Bax/bcl-2蛋白表达的影响。结果干预24h后,10-5mol/L维A酸CD437和阿维A对人黑素瘤A375细胞的增殖抑制率(PIR)和凋亡率分别为58.6%和43.25%,28.03%和17.13%(P<0.05),CD437促A375细胞G0/G1期阻滞,而阿维A无此作用;两药均上调A375细胞Bax蛋白表达和下调bcl-2蛋白表达,但CD437组与阿维A组差异无显著性。结论与阿维A相比较,CD437更有效抑制人黑素瘤A375细胞的增殖及更明显的凋亡诱导和G0/G1期阻滞作用;在辅助治疗黑素瘤方面,CD437比阿维A可能更具潜力。     

麦冬皂苷B通过抑制PI3K/Akt/mTOR通路诱导人黑色素瘤A375细胞凋亡

目的探讨麦冬皂苷B对人黑色素瘤(Melanoma)A375细胞增殖,凋亡和细胞周期的影响以及相关机制。方法麦冬皂苷B处理A375细胞后,采用CCK-8法检测细胞活力;流式细胞仪检测A375细胞周期变化及细胞凋亡水平;Hoechst33258荧光染色法观察细胞凋亡形态;免疫印迹法检测麦冬皂苷B对A375细胞PI3K,p-PI3K,AKT,p-AKT蛋白以及通路下游凋亡相关蛋白Bcl-2,Bax,Cleaved-caspase3表达的影响。结果麦冬皂苷B能抑制A375细胞增殖活力及PI3K/Akt/mTOR通路的活化;麦冬皂苷B促进了A375细胞内Bax和Cleaved-caspase 3的表达,抑制Bcl-2表达,诱导人黑色素瘤细胞发生凋亡;麦冬皂苷B阻滞了A375细胞细胞周期,G0/G1期细胞比例明显升高;PI3K/Akt/mTOR通路活化剂IGF-1处理A375细胞后抑制了麦冬皂苷B的上述作用。结论麦冬皂苷B能抑制A375细胞的增殖,诱导细胞发生凋亡,阻滞细胞周期于G0/G1期。     

生存素反义寡核苷酸对人恶性黑素瘤A375细胞生物学行为的影响

目的研究生存素反义寡核苷酸(AS-ODN)经脂质体介导转染对A375细胞增殖、凋亡的影响。方法合成生存素硫代反义寡核苷酸(AS-ODN),脂质体携带转染人恶性黑素瘤A375细胞。采用台盼蓝计数、软琼脂克隆形成试验、电镜、流式细胞仪检测AS-ODN对A375细胞增殖及凋亡的影响。通过裸鼠致瘤实验观察AS-ODN对A375细胞动物体内增殖的抑制作用。结果生存素反义寡核苷酸能降低G2/M期细胞百分比,诱导细胞凋亡发生,明显抑制A375细胞的生长和克隆形成,裸鼠体内A375细胞恶性增殖潜力下降。结论脂质体介导生存素AS-ODN能有效抑制A375细胞增殖、诱导肿瘤细胞凋亡。     

苦参碱抑制人恶性黑素瘤A375细胞株的侵袭

目的 探讨苦参碱对恶性黑素瘤细胞A375转移能力的影响及其作用机制。方法 采用MTT法和膜联蛋白-V-FITC/PI双染色法分别检测不同浓度苦参碱对A375细胞增殖和凋亡的影响,半定量RT-PCR分析经苦参碱干预后A375细胞乙酰肝素酶mRNA的表达变化,细胞黏附实验检测细胞黏附能力的改变,基质胶侵袭实验观察细胞侵袭能力的变化。结果 苦参碱浓度≥0.5mg/mL时可抑制A375细胞增殖并诱导细胞凋亡,其作用呈剂量依赖性;苦参碱浓度在0.125～0.5mg/mL时,能明显下调A375细胞乙酰肝素酶mRNA的表达,并能抑制细胞的黏附、侵袭能力(P<0.01),其抑制效应呈剂量依赖性,在不同浓度组间比较差异均有统计学意义(P<0.01)。结论 苦参碱在体外能抑制A375细胞的黏附、侵袭能力。苦参碱抗肿瘤侵袭可能与抑制肿瘤细胞增殖、诱导细胞凋亡以及下调乙酰肝素酶的表达有关。     

丹皮酚对人黑素瘤A375和M14细胞系增殖与凋亡的影响

目的:确定丹皮酚对体外培养人黑素瘤A375和M14细胞增殖与凋亡的影响。方法:利用CCK8检测黑素瘤A375和M14细胞的增殖抑制率;以流式细胞仪检测细胞周期变化、Annexin-V/PI法观察细胞凋亡的变化;用Hoechst33258染色法观察细胞凋亡的形态变化。结果:细胞周期显示丹皮酚处理过的A375和M14细胞G2/M期比例均高于对照组。以0 mmol/L、1.25 mmol/L、2.5 mmol/L、5 mmol/L丹皮酚作用24 h后,A375细胞的早期凋亡率分别为3.11%±0.53%,13.74%±1.73%,25.95%±0.57%和46.44%±0.81%;M14细胞的早期凋亡率分别为1.00%±0.08%,2.00%±0.01%,2.99%±0.29%和14.73%±0.94%,呈剂量依赖性诱导A375和M14细胞凋亡。经5 mmol/L丹皮酚作用后Hoechst33258染色示凋亡细胞形态改变。结论:丹皮酚对黑素瘤A375和M14细胞均具有抑制增殖和诱导凋亡的作用。     

International Summit on Cutaneous Antifungal Therapy, Focus on Tinea Capitis, Boston, Massachusetts, November 11–13, 1994

This article reports the highlights of presentations made at an international symposium held on November 11–13, 1994, in Boston, Massachusetts, on the subject of cutaneous antifungal therapy. Some of the key points pertaining to the epidemiology, etiology, pathogenesis, presentation, and management of tinea capitis are discussed.     

Titanium: a review on exposure,release, penetration,allergy, epidemiology,and clinical reactivity

Exposure to titanium (Ti) from implants and from personal care products as nanoparticles (NPs) is common. This article reviews exposure sources, ion release, skin penetration, allergenic effects, and diagnostic possibilities. We conclude that human exposure to Ti mainly derives from dental and medical implants, personal care products, and foods. Despite being considered to be highly biocompatible relative to other metals, Ti is released in the presence of biological fluids and tissue, especially under certain circumstances, which seem to be more likely with regard to dental implants. Although most of the studies reviewed have important limitations, Ti seems not to penetrate a competent skin barrier, either as pure Ti, alloy, or as Ti oxide NPs. However, there are some indications of Ti penetration through the oral mucosa. We conclude that patch testing with the available Ti preparations for detection of type IV hypersensitivity is currently inadequate for Ti. Although several other methods for contact allergy detection have been suggested, including lymphocyte stimulation tests, none has yet been generally accepted, and the diagnosis of Ti allergy is therefore still based primarily on clinical evaluation. Reports on clinical allergy and adverse events have rarely been published. Whether this is because of unawareness of possible adverse reactions to this specific metal, difficulties in detection methods, or the metal actually being relatively safe to use, is still unresolved.     

The Evaluation of the Impact of Age,Skin Tags,Metabolic Syndrome,Body Mass Index,and Smoking on Homocysteine,Endothelin-1, High-sensitive C-reactive Protein,and on the Heart

Background:

Skin tags (STs) are small, pedunculated skin-colored or brown papules that occur around any site where skin folds occur. The literature is short of comprehensive and controlled clinical studies aimed to evaluate the atherogenic risk factors in patients with STs.

Aim of Work:

The aim of this study is to evaluate the impact of age, STs, metabolic syndrome (METs), body mass index (BMI), and smoking on homocysteine (Hcy), endothelin-1 (ET-1), high-sensitive C-reactive protein (Hs-CRP), and on cardiovascular diseases.

Materials and Methods:

This study included 30 cardiac patients with STs, 30 non-cardiac patients with STs, and 30 healthy controls with neither heart disease nor STs. History of smoking, measurement of height, weight, BMI, waist circumference (WC), blood pressure, STs number, color, acanthosis nigricans, estimation of serum level of fasting glucose, triglycerides (TGs), cholesterol, high-dense lipoproteins (HDL), Hcy, ET-1, Hs-CRP, and the presence of the METs were elicited in the three groups.

Results:

Regarding the Hcy, ET-1, and Hs-CRP, the cardiac-STs group showed the highest levels and the control group showed the least (P < 0.001). The percents of patients with METs were 56.7% in the cardiac-STs, 40% in the non-cardiac-STs, and 0% in the control group (P < 0.001). Mean BMI exceeded the limit of obesity in the cardiac-STs group (30.9 ± 3.9) and the non-cardiac-STs group (32.6 ± 6) and was normal in the control group (24.7 ± 2.8). Hyperpigmented STs were present in 66.7% of the cardiac-STs group. Multivariate regression analysis for the independent effectors on Hcy level were the presence of STs (P < 0.001), METs (P = 0.001), and BMI (P = 0.024). Regarding ET-1, the effectors were the presence of STs and METs (P = 0.032). For Hs-CRP, effectors were the presence of STs (P < 0.001) and smoking (P = 0.040). Multivariate logistic regression of the predictors of cardiac disease showed that the independent predictors of the occurrence of cardiac disease were BMI (P < 0.001), STs (P = 0.002), and METs (P = 0.037).

Conclusion:

STs may act as a physical sign of underlying raised cardiac atherogenic factors. This may indicates an ongoing risk on coronary circulation which may indicate further corrective action, hopefully early enough. The association of ST with obesity and METs represents a Bermuda Triangle that act against the heart.