新型酪氨酸激酶抑制剂XCF-43b体外抗血管新生研究

目的 探究XCF-43b 体外抗血管新生机理.方法 鸡胚尿囊膜(CAM)检测化合物抑制血管新生能力,MTT检测其对HUVEC细胞增殖影响,划痕实验和微管形成实验检测化合物对HUVEC迁移和微管形成的影响,Western印迹检测VEGFR2信号通路相关蛋白表达情况.结果 XCF-43b能够抑制CAM血管新生,抑制HUVEC细胞增殖的IC50为(28.42±7.23) μmol/L,对在VEGF刺激下的HUVEC的IC50值为(9.03±1.28) μmol/L,此外,2.5 μmol/L的XCF-43b能够抑制HUVEC细胞的迁移和微管形成;且能够抑制VEGFR2及其下游信号因子的激活.结论 XCF-43b通过抑制VEGFR2信号通路来抑制血管新生.     

黄芪注射液对体外血管新生的影响

背景：血管新生受生长因子的影响,黄芪可与血管内皮生长因子具有协同促血管新生的功效,但机制尚不明确。 目的：通过与单一血管内皮生长因子干预比较,观察中药黄芪对体外血管新生的作用机制。 方法：将黄芪注射液及血管内皮生长因子作用于SD大鼠胸主动脉内皮细胞,应用细胞增殖、细胞迁移、小管形成实验观察黄芪注射液对体外血管新生的促进作用,用Western blot实验检测血管内皮生长因子的表达。 结果与结论：黄芪能明显促进大鼠胸主动脉内皮细胞的增殖(P < 0.01),迁移的细胞数增加(P < 0.01),胸主动脉内皮细胞的小管形成数增加(P < 0.01),并明显促进内皮细胞血管内皮生长因子的表达(P < 0.01)。说明黄芪能明显促进内皮细胞增殖、细胞迁移、小管形成,具有显著的促进体外血管新生作用,其机制可能是通过增加血管内皮生长因子的表达而实现的。     

黄芪-脉络宁胶原促进体外胸主动脉内皮细胞血管新生的实验研究

目的:探讨黄芪-脉络宁胶原对血管新生的细胞学影响及其可能机制,为其应用于临床提供理论依据。方法:应用增殖、迁移、管腔形成实验观察黄芪-脉络宁胶原对大鼠胸主动脉内皮细胞在血管新生各阶段的作用,用Western Bloting实验检测大鼠胸主动脉血管内皮细胞生长因子(VEGF)的表达率。结果:黄芪-脉络宁胶原能明显促进大鼠胸主动脉内皮细胞的增殖率(与对照组比较,增加了90.22%,P<0.01)、迁移率(与对照组比较增加了211.43%,P<0.01)、管腔形成数(是对照组的2.46倍,P<0.01),同时刺激VEGF蛋白表达比对照组增加63.8%(P<0.01)。结论:黄芪-脉络宁胶原能明显促进内皮细胞增殖、迁移、管腔形成,具有显著促体外血管新生作用,其机制可能与增加VEGF蛋白的表达有关。     

抗人VEGF受体Ⅱ胞外Ⅲ区单克隆抗体的生物学活性研究

目的研究抗KDR单体Ycom1D3抑制VEGF诱导脐静脉内皮细胞（HUVEC）增殖的体外生物学活性。方法采用FACS鉴定Ycom1D3与抗原结合特异性，采用免疫共沉淀测定Ycom1D3阻断VEGF165刺激KDR酪氨酸激酶受体磷酸化作用，并采用[^3H]-Thymidine掺入法、内皮细胞损伤愈合试验和内皮细胞血管腔形成实验进一步确定Ycom1D3抑制VEGF165诱导内皮细胞增殖的中和活性。结果Ycom1D3不但能与HUVEC结合，而且能阻断由VEGF165刺激HUVEC表面KDR酪氨酸激酶受体磷酸化，进而显著抑制VEGF165诱导HUVEC增殖、迁移及体外三维胶原模型上内皮细胞毛细血管样结构的形成。结论Ycom1D3可以通过封闭KDR而抑制VEGF活性，在肿瘤及其它血管新生疾病治疗中具有潜在应用前景。     

青蒿琥酯对新生血管生长与成型影响的实验研究

目的通过观察新生血管生长发育与成型过程的形态学变化，研究青蒿琥酯对新生血管形成的影响。方法采用鸡胚绒毛尿囊膜模型、大鼠主动脉环无血清培养及人脐静脉内皮细胞体外培养，检测青蒿琥酯在新生血管形态发育过程中的作用。结果青蒿琥酯可影响血管内皮生长与实心条索形成，使血管生长期明显滞后，抑制血管生长。结论青蒿琥酯能通过干扰血管生长发育与成型而抑制血管生成。     

姜黄素抑制HGF诱导血管内皮细胞迁移和VEGF表达的体内外研究

目的:探索姜黄素抑制肝细胞生长因子(HGF)诱导血管生成的分子机制。方法:利用管腔形成实验、划痕实验、Western blot实验和动物实验观察姜黄素、c-Met抑制剂SU11274、磷脂酰肌醇3-激酶(PI3K)抑制剂LY294002和m TOR抑制剂rapamycin对HGF诱导的内皮细胞迁移、管腔形成能力、血管内皮生长因子(VEGF)表达、相关信号通路和瘤体内血管密度的影响。结果:姜黄素可显著抑制HGF诱导内皮细胞发生迁移、小管形成及VEGF的表达,同时抑制c-Met/AKT/m TOR/S6通路的磷酸化,并可减少瘤体内VEGF的表达和微血管密度。使用c-Met抑制剂SU11274、PI3K抑制剂LY294002或m TOR抑制剂rapamycin能得到和姜黄素相似的效应。结论:姜黄素抑制HGF诱导的血管生成可能是通过抑制c-Met/AKT/m TOR/S6信号通路活化实现的。     

血管内皮生长因子的生物学及其在临床的初步应用

血管内皮生长因子(VEGF)是内皮细胞特异性的有丝分裂原。它诱导内皮细胞增殖、促进内皮细胞迁移，并抑制内皮细胞凋亡，在调节血管和淋巴管新生中起重要作用。VEGF也是胚胎发育、软骨内骨形成、女性生殖系统、以及肿瘤和眼球内血管新生所必需的。另外，VEGF也可诱导血小板粘附于血管内皮细胞而出现高凝状态。目前，有许多临床实验正在评价VEGF在血管新生依赖性疾病的促血管新生作用和抗血管新生药物用于治疗的效果。     

粘着斑激酶在血管内皮细胞黏附和迁移中的作用

目的 采用粘着斑激酶（focal adhesion kinases,FAK)抑制剂抑制FAK在Y397位点的酪氨酸磷酸化,测定不同浓度的FAK抑制剂的对内皮细胞黏附、迁移及下游信号Rac1蛋白表达的影响,探索粘着斑激酶在内皮细胞黏附和迁移中的作用。方法 运用内皮损伤模型（划痕法）测定FAK抑制剂在2、4、8、24 h各时间点对EA.hy 926细胞迁移的影响。Western blot结合免疫荧光测定不同浓度的0~250 nmol/mL的FAK抑制剂的加入对Rac1蛋白分布和表达的影响。结果 随着FAK抑制剂浓度的增加,细胞迁移距离减少,Rac1蛋白表达逐渐减弱。结论 抑制FAK的磷酸化将抑制内皮细胞的黏附和迁移的生物学行为,下游Rac1蛋白表达降低。内皮细胞的黏附和迁移与FAKRho GTPases 信号轴相关。     

青蒿琥酯对人骨髓瘤细胞抗血管生成的作用

目的:研究青蒿琥酯对人RPMI-8226细胞诱导血管新生的抑制作用。方法:采用MTT法检测青蒿琥酯对RPMI-8226细胞增殖抑制作用;通过鸡胚绒毛尿囊膜体内血管生长实验,观察青蒿琥酯对RPMI-8226细胞诱导体内血管生成的影响;免疫蛋白印迹检测鸡胚绒毛尿囊膜内血管内皮生长因子(VEGF)和血管紧张素1(Ang-1)含量的表达变化。结果:青蒿琥酯以时间、剂量依赖方式抑制RPMI-8226细胞增殖;24h和48h后,其IC50值分别为(36.33±2.65)μmol/L和(14.31±3.28)μmol/L。在鸡胚绒毛尿囊膜体内血管生长实验中,经3、6、12μmol/L青蒿琥酯处理后,与单纯RPMI-8226细胞组比较,新生血管数目分别减少21.9%、38.2%和76.9%,差异有统计学意义;同时鸡胚绒毛尿囊膜内VEGF含量分别显著下降22.2%、34.2%和52.6%;Ang-1蛋白表达量分别显著下降15.6%、24.2%和39.6%。结论:青蒿琥酯具有抑制RPMI-8226细胞诱导血管新生的作用,其作用机制与下调RPMI-8226细胞的VEGF和Ang-1表达有关。     

血管内皮生长因子和内皮抑素对血管生成的作用研究进展

血管内皮生长因子（VEGF）是一种多功能糖蛋白，是由肿瘤细胞或宿主的非内皮细胞分泌的特异的内皮细胞有丝分裂因子，是最主要的促进血管生成因子。它具有促进血管通透性增加、血管内皮细胞分裂、增殖及诱导血管生成等作用。内皮抑素（ES）是胶原XⅧC末端降解片段，体内、体外实验表明内皮抑素能有效抑制血管内皮细胞增殖、迁移及新生血管形成，是一种特异性的目前为止作用最强的血管形成抑制荆。但其确切的抗血管形成的作用机制尚未阐明。现就血管内皮生长因子、内皮抑素在血管生成中的作用作一综述。     

A short course on virology / vectorology / gene therapy

For people starting off in the field of gene therapy, the encountered terminology is often quite confusing. Moreover, the background on basic virology may be modest. The following introduction provides a head start to any novice willing to gain more in-depth knowledge on the subject. The development of gene therapy is also addressed from a historical perspective.     

Effect of estrogen/progestin potency on lipid/lipoprotein cholesterol

We studied 374 women taking oral contraceptives, 284 women taking estrogen preparations after menopause, and 1086 women taking no hormones, to determine the relation of plasma lipids and lipoprotein cholesterol concentrations to various types of estrogen/progestin formulations. Premenopausal women, using oral contraceptives containing a relatively low dose of estrogen combined with a medium or high dose of progestin (Norlestrin, Ovral, or Demulen) had a 24 per cent higher median concentration of low-density-lipoprotein cholesterol than did those not using hormones (P less than 0.05). Women using oral contraceptives that are high in estrogen and low in progestin (Enovid or Oracon) had significantly higher concentrations of high-density-lipoprotein cholesterol than did nonusers; those using Ovral, a low-estrogen and high-progestin formulation, had significantly lower levels of high-density-lipoprotein cholesterol. In postmenopausal women the use of estrogen was associated with concentrations of low-density-lipoprotein cholesterol that were 11 to 19 per cent below the levels in postmenopausal women who did not use hormones. The effects of estrogen-progestin balance on low-density and high-density lipoproteins may underlie the increased incidence of stroke and myocardial infarction in women of childbearing age who take oral contraceptives.     

紫杉醇PCL-PEG-PCL温敏性缓释凝胶的制备及性能研究

目的 利用聚己内酯-聚乙二醇-聚己内酯(PCL1250-PEG1500-PCL1250)两亲性聚合物温敏凝胶作为载体材料,构建疏水性抗肿瘤药物紫杉醇的载药体系.方法 以辛酸亚锡为催化剂、聚乙二醇为引发剂,引发己内酯单体开环聚合,合成PCL1250-PEG1500-PCL1250三嵌段共聚物.通过核磁共振氢谱及凝胶渗透色谱对其组成、结构及分子量进行表征:制备不同凝胶浓度及初始载药量的载药温敏凝胶,并对其相转变性能、体外药物释放行为以及体内的生物降解性能进行考察.结果 核磁共振及凝胶渗透色谱测定结果表明:合成的共聚物组成与初始投料比一致,符合设计的PCL1250-PEG1500-PCL1250嵌段聚合物结构;该凝胶在15%～30%浓度区间内,具备温敏性溶胶-凝胶相转变能力;该温敏凝胶对紫杉醇具有可控的药物缓释能力,通过改变凝胶浓度及初始载药量可调节药物释放速率和维持释放的时间.小鼠背部皮下注射PCL1250-PEG1500-PCL1250溶胶后在体内迅速原位凝胶化,凝胶随植入时间逐渐降解至45 d时基本降解完全.结论 PCL1250-PEG1500-PCL1250温敏凝胶作为紫杉醇载药体系具有良好的药物控释能力和体内生物降解性能.     

Update on HIV/HCV Coinfection

Liver disease is currently one of the leading causes of hospitalization and death in HIV-positive individuals. Coinfection with the hepatitis C virus (HCV) is a major contributor to this trend. Besides hepatic damage, which is enhanced in the presence of HIV-associated immunosuppression, HCV may contribute to disease in coinfected individuals by potentiating immune activation and chronic inflammation, which ultimately account for an increased risk of cardiovascular events, kidney disease, and cancers in this population. Fortunately, hepatitis C therapeutics has entered a revolutionary era in which we hope that most patients treated with the new oral direct-acting antivirals (DAA) will be cured. However, many challenges preclude envisioning a prompt elimination of HCV from the coinfected population. Issues that should be addressed include the following: (1) rising incidence of acute hepatitis C in men who have sex with men, and expansion/recrudescence of injection drug use in some settings/regions; (2) adverse drug interactions between antiretrovirals and DAA; and (3) high cost of DAA, which may lead many to defer or fail to access appropriate therapy.     

紫杉醇PCL—PEG—PCL温敏性缓释凝胶的制备及性能研究

目的利用聚己内酯-聚乙二醇-聚己内酯（PCL1250-PEG1500-PCL1250）两亲性聚合物温敏凝胶作为载体材料,构建疏水性抗肿瘤药物紫杉醇的载药体系。方法以辛酸亚锡为催化剂、聚乙二醇为引发剂,引发己内酯单体开环聚合,合成PCL1250-PEG1500-PCL1250三嵌段共聚物。通过核磁共振氢谱及凝胶渗透色谱对其组成、结构及分子量进行表征;制备不同凝胶浓度及初始载药量的载药温敏凝胶,并对其相转变性能、体外药物释放行为以及体内的生物降解性能进行考察。结果核磁共振及凝胶渗透色谱测定结果表明：合成的共聚物组成与初始投料比一致,符合设计的PCL1250-PEG1500-PCL1250嵌段聚合物结构;该凝胶在15％～30％浓度区间内,具备温敏性溶胶-凝胶相转变能力;该温敏凝胶对紫杉醇具有可控的药物缓释能力,通过改变凝胶浓度及初始载药量可凋节药物释放速率和维持释放的时间。小鼠背部皮下注射PCL1250-PEG1500-PCL1250溶胶后在体内迅速原位凝胶化,凝胶随植入时间逐渐降解至45d时基本降解完全。结论PCL1250-PEG1500-PCL1250温敏凝胶作为紫杉醇载药体系具有良好的药物控释能力和体内生物降解性能。     

Biomimetic calcium phosphate coatings on Polyactive 1000/70/30.

Precalcification of Polyactive 1000/70/30 with a biomimetic calcium phosphate coating is expected to enhance the bioactivity of this biodegradable polymer for the application as bone filler or scaffold of bone tissue engineering. This study presents a 1-day one-step incubation method to obtain either amorphous or bone-like apatitic calcium phosphate coating on Polyactive 1000/70/30. Either dense plates or three-dimensional porous blocks of the polymer were incubated in a simplified but concentrated simulated body fluid-derived solution at 37 degrees C. By bubbling CO2 gas, a solution was prepared with calcium and phosphate ion concentrations five times of that of regular simulated body fluid. With controlled stirring, the CO2 was released out of the solution and exchanged by air. The pH of the solution increased to induce coating formation. Adjusting stirring rate and CO2/air exchange rate controlled the process kinetics. The reaction kinetics had little influence on the crystallographic structure of the final coating mineral for a given solution composition as shown by Fourier transform infrared spectroscopy and X-ray diffraction. However, the interface structure between the coating and substrate was kinetics-dependent. A fast precipitation condition resulted in a uniform but superficial calcification pattern at the surface of polymer. A slow process by selecting either a slow stirring or a slow CO2/air exchange, on the contrary, induced a localized but deep inside calcification pattern. A tensile test showed no statistically significant difference in the mechanical properties among uncoated and coated polymers. The cracking behavior of coatings from different kinetics, however, exhibited different manners, as can be attributed to different interface structures and interfacial strengths.