人参皂苷单体Rh2(S亚型)对人急性髓系白血病细胞株KG1α增殖、凋亡的影响及其机制

目的探讨人参皂苷单体Rh2(S亚型)对人急性髓系白血病细胞株KG1α增殖、凋亡的影响及其机制。方法取对数生长期的KG1α细胞,分为两组:空白对照组(常规培养)和人参皂苷单体Rh2(S)组,采用MTT法检测细胞的增殖活力,倒置显微镜观察细胞的形态及数量,透射电镜观察细胞的超微结构,流式细胞仪检测细胞周期的分布,Real-time PCR检测细胞中β-catenin基因mRNA水平,免疫细胞化学法检测细胞中β-catenin、TCF4、CyclinD1蛋白的定位及表达,Western blot检测细胞中β-catenin、TCF4、CyclinD1蛋白的表达水平。结果人参皂苷单体Rh2(S)对KG1α细胞的增殖具有明显的抑制作用,且呈浓度和时间依赖性。与空白对照组比较,Rh2(S)作用48 h后,可见KG1α细胞分散生长,数量明显减少;可见数量不等,程度不同的凋亡细胞;G0/G1期细胞比例明显上升(P<0.05),G2+M和S期细胞比例明显下降(P<0.05);细胞中β-catenin基因mRNA水平明显降低(P<0.01)。β-catenin、TCF4、CyclinD1蛋白的表达水平明显降低(P<0.05或P<0.01)。结论人参皂苷单体Rh2(S亚型)对KG1α细胞具有明显的增殖抑制作用,其机制可能抑制Wnt/β-catenin/TCF4/CyclinD1信号通路,使细胞周期阻滞,诱导细胞凋亡。     

人参皂苷单体Rh2对人鼻咽癌CNE2细胞株增殖、凋亡的影响及其机制

目的研究人参皂苷单体Rh2对人鼻咽癌CNE2细胞株增殖、凋亡的影响及其可能的机制。方法取对数生长期的CNE2细胞,用不同浓度的Rh2(20、40、60、80、100μmol/L)处理不同时间(24、48、72 h),并设对照组(正常培养),采用MTT法检测各组细胞的增殖活力;用最适作用浓度的Rh2分别处理CNE2细胞24、48、72 h,采用Hoechst荧光染色法观察细胞凋亡形态;流式细胞术检测细胞凋亡率、周期分布以及膜电位的变化;Western blot法检测细胞凋亡相关蛋白Bax、Bcl-2、Caspase-3、CyclinD1、P53的表达水平。结果 Rh2对CNE2细胞的增殖具有明显的抑制作用,且呈时间和剂量依赖性,60μmol/L Rh2作用72 h为最适作用浓度和时间。经60μmol/L的Rh2作用48、72 h后,凋亡细胞数目增多,凋亡细胞体积变小,细胞核出现染色质不均匀,核浓缩聚集、碎裂,边集程度增大等现象。与对照组比较,经60μmol/L的Rh2作用24、48、72 h,CNE2细胞的凋亡率逐渐增加(P0.01);G0/G1期细胞比例逐渐升高(P0.01),S期(P0.01)和G2/M期细胞比例逐渐下降;细胞的膜电位逐渐降低(P0.05);促凋亡蛋白Bax、激活型Caspase-3和P53蛋白表达上调(P0.05),抗凋亡蛋白Bcl-2和细胞周期相关蛋白CyclinD1表达下调(P0.05)。结论人参皂苷单体Rh2具有抑制CNE2细胞增殖,使细胞周期阻滞在G0/G1期,诱导细胞凋亡的作用,其机制可能是通过Caspase/CyclinD1信号通路实现的。     

ZD 1839联合顺铂对人食管癌细胞HE-2增殖的影响

目的分析ZD1839联合顺铂用药对人食管细胞HE-2增殖的影响。方法在ZD1839和顺铂单独用药和联合用药情况下,采用MTT法检测不同浓度、不同作用时间的ZD1839与顺铂对人食管癌细胞HE-2增殖的抑制率;取各自48 h IC50值的半量为ZD1839与顺铂的药物浓度,流式细胞仪检测HE-2细胞凋亡及细胞周期的变化。结果ZD1839和顺铂均可抑制HE-2细胞的增殖,抑制效果呈剂量和用药时间依赖性(P均0.05);顺铂将细胞生长阻滞在S期,而ZD1839将细胞生长阻滞在G_0/G_1期,ZD1839联合顺铂用药,将细胞生长阻滞在G_0/G_1和S期;ZD1839联合顺铂用药的细胞增殖抑制率及细胞凋亡率均明显高于单独用药(P均0.01)。结论 ZD1839对食管癌细胞HE-2的增殖有抑制作用,且该抑制作用呈剂量和用药时间依赖性。同时,ZD1839可增强顺铂抑制食管癌细胞HE-2增殖的效应。     

克菌丹对人支气管上皮细胞周期及凋亡的影响

探讨克菌丹对人支气管上皮细胞周期及凋亡的影响.人支气管上皮细胞(16HBE)在加或不加S9代谢活化系统条件下,经0.0625～1.0 mg/L剂量的克菌丹染毒不同次数,应用流式细胞仪检测细胞周期及凋亡率的改变.在不加S9条件下,经1次染毒处理后,随着染毒剂量的增加,G0/G1期细胞显著减少,G2/M期细胞显著增加,凋亡细胞数减少(P<0.05);2次染毒处理后,各剂量组细胞出现G0/G1期阻滞,S期细胞数显著减少,低剂量组的凋亡细胞数显著增加(P<0.05),但高剂量组未出现明显的细胞凋亡现象.在代谢活化系统条件下,各染毒组的细胞周期和凋亡变化与溶剂对照组相比无显著性变化.经克菌丹染毒处理后,16HBE细胞周期呈现增殖性改变,细胞增殖失控可能是克菌丹遗传损伤效应后的早期分子事件.     

透明质酸对人骨性关节炎软骨细胞凋亡及细胞周期的影响

目的观察透明质酸(Hyaluronic acid,HA)对人骨性关节炎(Osteoarthritis,OA)软骨细胞凋亡及细胞周期的影响,以探讨HA保护软骨细胞的作用机制。方法分离人正常软骨细胞和OA软骨细胞,传至第2代后,分别经HA处理24 h,采用MTT法检测细胞的增殖活力,流式细胞术检测细胞凋亡率和细胞周期。结果 HA能明显降低人OA软骨细胞的凋亡率(P<0.05),提高细胞的增殖活力、S期比例和增殖指数(P<0.05),且对正常人软骨细胞的增殖活力和凋亡无明显影响。结论 HA可促进OA软骨细胞的分裂与增殖,降低细胞凋亡率,从而对软骨细胞发挥保护作用。     

神经纤毛蛋白1基因RNA干扰质粒对胃腺癌细胞SGC7901增殖和凋亡的影响

目的探讨神经纤毛蛋白1(Neuropilin1,NRP1)基因RNA干扰质粒对胃腺癌细胞SGC7901增殖和凋亡的影响。方法构建NRP1基因特异性shRNA表达质粒,经脂质体介导转染入人胃腺癌SGC7901细胞。采用Western blot法检测细胞中NRP1蛋白的表达水平,应用流式细胞术和Annexin-V-FITC/PI法检测细胞的增殖水平和凋亡率。结果经酶切及测序鉴定证明,shRNA-NRP1质粒构建正确,转染SGC7901细胞48h后,能有效抑制NRP1蛋白的表达,G0/G1期细胞百分比显著升高,S期细胞显著减少,细胞凋亡率增加。结论 shRNA-NRP1质粒能有效抑制胃腺癌SGC7901细胞株NRP1蛋白的表达,细胞周期阻滞在G0/G1期,从而降低细胞的增殖水平,诱导细胞进入凋亡期。     

联氨基姜黄素对乳腺癌细胞MCF-7增殖和凋亡的影响及其机制

目的探讨联氨基姜黄素对人乳腺癌细胞MCF-7增殖和凋亡的影响及其机制。方法采用MTT法检测联氨基姜黄素对MCF-7细胞的抗增殖效应,Hochest33258染色观察细胞形态学变化,流式细胞术分析细胞的周期分布和凋亡情况,Western blot检测MCF-7细胞中Bcl-2、Bax、Cyclin D1和Survivin蛋白的表达变化。结果联氨基姜黄素可抑制MCF-7细胞的增殖,IC50为2.56μmol/L,而姜黄素的IC50为21.22μmol/L;联氨基姜黄素染色24 h后,MCF-7细胞出现核荧光强度增强、颗粒状荧光等凋亡特征;凋亡细胞比率明显增加,并可阻滞细胞周期于G1期,且呈一定的剂量依赖性;联氨基姜黄素可使MCF-7细胞中Bcl-2、Cyclin D1、Survivin蛋白表达水平明显降低,而Bax表达增加。结论联氨基姜黄素具有抑制MCF-7细胞增殖、促进凋亡、阻滞细胞周期于G1期的作用,其机制可能与Bcl-2、Bax、Cyclin D1、Survivin蛋白的表达改变有关。     

百子莲脱水素蛋白对人皮肤细胞损伤的保护作用

应用角质形成细胞(HaCaT)与成纤维细胞(NHSF)建立脱水、光老化及氧化应激模型评价百子莲Y_2SK_2与SK_3型脱水素蛋白对人皮肤细胞在不同胁迫条件下的保护功能。结果表明:0.01～10μmol/L为两种脱水素的安全作用浓度。光老化与氧化应激模型会造成人皮肤细胞发生氧化损伤与细胞凋亡。10μmol/L ApSK_3可将皮肤细胞超低温冻存后细胞活性提升57%～91%。ApSK_3可明显改善皮肤细胞在脱水处理中的胁迫损伤,两种脱水素在光老化与氧化应激模型中对皮肤细胞均有抗氧化保护作用,可显著降低细胞中MDA含量约10%～36%,提升HaCaT细胞的SOD酶活性;ApSK_3可有效抑制皮肤细胞在氧化胁迫下的casepase-3与casepase-8的酶活性,降低细胞程序性死亡事件发生。该研究发现脱水素蛋白在胁迫伤害中对人皮肤细胞具有保护作用,其机制可能与增强细胞抗氧化性以及参与细胞凋亡过程有关。     

吴茱萸碱对人结肠癌lovo细胞生长的抑制作用

目的探讨吴茱萸碱(Evodiamine,Evo)在体内外对人结肠癌lovo细胞生长的抑制作用及其机制。方法采用MTT法检测Evo对人结肠癌lovo细胞、人乳腺癌MDA-MB-231细胞以及人肺癌A549细胞生长的影响;流式细胞术分析Evo对lovo细胞细胞周期和细胞凋亡的影响;采用Evo治疗lovo细胞荷瘤裸鼠,并绘制肿瘤生长曲线;Westernblot法检测Evo对lovo细胞和肿瘤组织中Bcl-2及procaspase-3表达的影响。结果 Evo能抑制lovo细胞生长(P<0.01),促进MDA-MB-231细胞增殖(P<0.01),对A549细胞无明显作用(P>0.05);可将lovo细胞阻滞于S期(P<0.01),并呈时间依赖性诱导其凋亡(P<0.01);能抑制lovo细胞荷瘤裸鼠肿瘤生长(P<0.05);Westernblot检测结果显示,Evo在体内外均可降低lovo细胞Bcl-2及procas-pase-3的表达。结论 Evo可通过抑制Bcl-2表达,激活caspase-3,诱导凋亡,从而抑制lovo细胞的生长。     

小球藻类金属硫蛋白抗紫外辐射的作用研究

建立了小鼠胚胎成纤维(NIH/3T3)细胞紫外辐射损伤的实验模型,考察小球藻类金属硫蛋白(Zn-MT-like)对NIH/3T3细胞紫外辐射的保护作用。结果表明,小球藻Zn-MT-like对NIH/3T3细胞的生长无抑制作用,且具有较强的抗紫外辐射能力。质量浓度为10 g/L的小球藻Zn-MT-like可显著减少NIH/3T3细胞空泡、降低细胞裂解的程度,可使经紫外辐射的NIH/3T3细胞保持较好的活性。     

Protective Effect of the Ethyl Acetate Fraction of Sargassum muticum Against Ultraviolet B-Irradiated Damage in Human Keratinocytes

The aim of this study was to investigate the cytoprotective properties of the ethyl acetate fraction of Sargassum muticum (SME) against ultraviolet B (UVB)-induced cell damage in human keratinocytes (HaCaT cells). SME exhibited scavenging activity toward the 1,1-diphenyl-2-picrylhydrazyl radicals and hydrogen peroxide (H(2)O(2)) and UVB-induced intracellular reactive oxygen species (ROS). SME also scavenged the hydroxyl radicals generated by the Fenton reaction (FeSO(4) + H(2)O(2)), which was detected using electron spin resonance spectrometry. In addition, SME decreased the level of lipid peroxidation that was increased by UVB radiation, and restored the level of protein expression and the activities of antioxidant enzymes that were decreased by UVB radiation. Furthermore, SME reduced UVB-induced apoptosis as shown by decreased DNA fragmentation and numbers of apoptotic bodies. These results suggest that SME protects human keratinocytes against UVB-induced oxidative stress by enhancing antioxidant activity in cells, thereby inhibiting apoptosis.     

协同增效与全效防晒化妆品

本文从添加UVB致伤性紫外线吸收剂、UVA致黑性紫外线吸收剂、UVAB全波段紫外线吸收剂、还原已晒黑黑色素、抑制酪氨酸酶、剥脱沉积色素死皮、成膜、抗过敏与刺激、保湿、增效SPF与PFA值、抗自由基与光老化、晒后修复、紫外线屏蔽、内皮素拮抗和赋活肌肤细胞等十五个方面介绍了协同增效与全效防晒化妆品的开发。     

PET/纳米TiO2抗紫外纤维的制备及性能研究

将金红石型TiO2添加至聚合反应体系中进行原位聚合,得到PET／纳米TiO2复合材料,通过透射 电镜(TEM)、扫描探针显微镜(SPM)研究了纳米TiO2在PET基体中的分散情况。将复合材料纺制成纤维, 并进行了力学性能、抗紫外性能等测试。结果表明,金红石型TiO2在基体中分散较均匀,TiO2质量分数为 1％时,基本呈纳米尺寸分散;PET／纳米TiO2纤维中含1％TiO2时,断裂强度较纯PET纤维下降6％左右,断 裂伸长率、结晶度也有所下降。织物对UVA,UVB波段的紫外线具有优异的屏蔽效果,抗紫外因子(UPF 值)可达50以上。     

防晒产品抗紫外线效能的研究

采用紫外分光光度法和体外ＳＰＦ测定法分别研究了ＵＶＢ和ＵＶＡ防晒剂紫外光谱特性;ＵＶＢ、ＵＶＡ防晒剂、成膜剂以及防晒时间对防晒产品ＳＰＦ的影响。结果表明：ＵＶＢ和ＵＶＡ复配可明显提高对紫外线的吸收能力;在含ＵＶＢ的防晒产品中加入ＵＶＡ防晒剂可显提高防晒产品ＳＰＦ值;防晒时间对部分防晒产品ＳＰＦ值有一定的影响;成膜剂能使防晒产品ＳＰＦ同线显上升。上述实验结果对进一步探讨防晒产品抗紫外线效能具有重     

The Photoprotective Effect of S-Methylmethionine Sulfonium in Skin

S-Methylmethionine sulfonium (SMMS) was reported to have wound-healing effects; we therefore have investigated the photoprotective effect of SMMS in the present study. SMMS increased the viability of keratinocyte progenitor cells (KPCs) and human dermal fibroblasts (hDFs) following ultraviolet B (UVB) irradiation, and reduced the UVB-induced apoptosis in these cells. SMMS increased the phosphorylation of extracellular signal-regulated kinases (ERK), and the inhibitor of the mitogen-activated protein kinase pathway significantly decreased the SMMS-induced viability of KPCs and hDFs. In addition, SMMS attenuated the UVB-induced reactive oxygen species (ROS) generation in KPCs and hDFs. SMMS induced the collagen synthesis and reduced the matrix metalloproteinase-1 expression in UVB-irradiated hDFs. In animal studies, application of 5% and 10% SMMS before and after UVB-irradiation significantly decreased the UVB-induced erythema index and depletion of Langerhans cells. In summary, SMMS protects KPCs and hDFs from UVB irradiation, and reduces UVB-induced skin erythema and immune suppression. Therefore, SMMS can be used as a cosmetic raw material, and protect skin from UVB.     

Protective Effects of Ethanol Extract of Brazilian Green Propolis and Apigenin against Weak Ultraviolet Ray-B-Induced Barrier Dysfunction via Suppressing Nitric Oxide Production and Mislocalization of Claudin-1 in HaCaT Cells

Once weak ultraviolet ray-B (UVB) irradiates the skin cells, the generation of reactive nitrogen species (RNS), but not reactive oxygen species (ROS), is stimulated for the mislocalization of claudin-1 (CLDN1), an essential protein for forming tight junctions (TJs). Since our skin is constantly exposed to sunlight throughout our lives, an effective protection strategy is needed to maintain the skin barrier against weak UVB. In the present study, we investigated whether an ethanol extract of Brazilian green propolis (EBGP) and flavonoids had a protective effect against weak UVB irradiation-induced barrier dysfunction in human keratinocyte-derived HaCaT cells. A pretreatment with EBGP suppressed TJ permeability, RNS production, and the nitration level of CLDN1 in the weak UVB-exposed cells. Among the propolis components, apigenin and apigenin-like flavonoids have potent protective effects against NO production and the mislocalization of CLDN1 induced by UVB. The analyses between structures and biological function revealed that the chemically and structurally characteristic flavonoids with a hydroxyl group at the 4′ position on the B-ring might contribute to its protective effect on barrier dysfunction caused by weak UVB irradiation. In conclusion, EBGP and its component apigenin protect HaCaT cells from weak UVB irradiation-induced TJ barrier dysfunction mediated by suppressing NO production.     

UVB Inhibits Proliferation,Cell Cycle and Induces Apoptosis via p53, E2F1 and Microtubules System in Cervical Cancer Cell Lines

Ultraviolet (UV) exposure has been linked to skin damage and carcinogenesis, but recently UVB has been proposed as a therapeutic approach for cancer. Herein, we investigated the cellular and molecular effects of UVB in immortal and tumorigenic HPV positive and negative cells. Cells were irradiated with 220.5 to 1102.5 J/m² of UVB and cell proliferation was evaluated by crystal violet, while cell cycle arrest and apoptosis analysis were performed through flow cytometry. UVB effect on cells was recorded at 661.5 J/m² and it was exacerbated at 1102.5 J/m². All cell lines were affected by proliferation inhibition, cell cycle ablation and apoptosis induction, with different degrees depending on tumorigenesis level or HPV type. Analysis of the well-known UV-responsive p53, E2F1 and microtubules system proteins was performed in SiHa cells in response to UVB through Western-blotting assays. E2F1 and the Microtubule-associated protein 2 (MAP2) expression decrease correlated with cellular processes alteration while p53 and Microtubule-associated Protein 1S (MAP1S) expression switch was observed since 882 J/m², suggesting they were required under more severe cellular damage. However, expression transition of α-Tubulin3C and β-Tubulin was abruptly noticed until 1102.5 J/m² and particularly, γ-Tubulin protein expression remained without alteration. This study provides insights into the effect of UVB in cervical cancer cell lines.     

Disease-Dependent Antiapoptotic Effects of Cannabidiol for Keratinocytes Observed upon UV Irradiation

Although apoptosis of keratinocytes has been relatively well studied, there is a lack of information comparing potentially proapoptotic treatments for healthy and diseased skin cells. Psoriasis is a chronic autoimmune-mediated skin disease manifested by patches of hyperproliferative keratinocytes that do not undergo apoptosis. UVB phototherapy is commonly used to treat psoriasis, although this has undesirable side effects, and is often combined with anti-inflammatory compounds. The aim of this study was to analyze if cannabidiol (CBD), a phytocannabinoid that has anti-inflammatory and antioxidant properties, may modify the proapoptotic effects of UVB irradiation in vitro by influencing apoptotic signaling pathways in donor psoriatic and healthy human keratinocytes obtained from the skin of five volunteers in each group. While CBD alone did not have any major effects on keratinocytes, the UVB treatment activated the extrinsic apoptotic pathway, with enhanced caspase 8 expression in both healthy and psoriatic keratinocytes. However, endoplasmic reticulum (ER) stress, characterized by increased expression of caspase 2, was observed in psoriatic cells after UVB irradiation. Furthermore, decreased p-AKT expression combined with increased 15-d-PGJ₂ level and p-p38 expression was observed in psoriatic keratinocytes, which may promote both apoptosis and necrosis. Application of CBD partially attenuated these effects of UVB irradiation both in healthy and psoriatic keratinocytes, reducing the levels of 15-d-PGJ₂, p-p38 and caspase 8 while increasing Bcl2 expression. However, CBD increased p-AKT only in UVB-treated healthy cells. Therefore, the reduction of apoptotic signaling pathways by CBD, observed mainly in healthy keratinocytes, suggests the need for further research into the possible beneficial effects of CBD.     

漆酚甲醛缩聚物/醇酸树脂IPN的研究

本文制备了漆酚缩甲醛聚合物 (UF)与醇酸树脂 (AR)组成的同步互穿网络共混物 ,并对共混物涂膜的物理机械性能 ,抗溶剂性能和动态力学性能进行了研究。结果表明 ,IPN共混可以改善UF的柔韧性、抗紫外线性能等 ,并且能提高漆液的固体含量     

ABS塑料专用漆的研制

采用优化筛选的方法，研制出ABS塑料专用漆的配方。实验结果表明；以热塑性丙烯酸树脂RJ-6—61为主树脂。在高温、高湿和强紫外线照射条件下，辅助树脂采用醋酸-丁酸纤维素（CAB-381—20）为宜；而在低温、低湿和弱紫外线照射条件下，辅助树脂选用1／4s硝化棉效果最佳。