蝎毒多肽提取物的抗血管生成作用

用不同浓度的东亚钳蝎素的多肽提取物PESV(4～20μg／ml)作用于人脐静脉内皮细胞(HUVEC),观察HUVEC增殖活性和凋亡变化,增殖活性检测采用BrdU掺入的ELISA法,凋亡水平和凋亡相关基因Bcl-2和Bax表达的检测采用流式细胞术检测;用鸡胚尿囊膜(CAM)显示PESV对血管生成的抑制作用。结果显示,PESV抑制HUVEC的增殖,而对乳腺癌细胞MDA-MB-231的增殖无明显影响;PESV作用72h后,HUVEC凋亡相关基因Bcl-2表达降低,Bax表达增加,凋亡细胞比例增至10．5％,明显高于对照组;0．5mgPESV能明显抑制CAM新生血管的形成。因此,PESV具有良好的体外抗肿瘤血管生成活性,PESV作为一种肿瘤血管抑制剂的天然药物来源,其有效成分和药理作用有待进一步研究。     

原核表达Arresten蛋白抑制血管生成作用

目的:研究原核表达的Arresten蛋白纯化品对血管内皮细胞及血管生成的抑制作用。方法:MTT法检测Arresten蛋白对人脐静脉内皮细胞(HUVEC)增殖的影响;流式细胞仪分析Arresten蛋白作用下HUVEC凋亡的情况;细胞迁移实验观察Arresten蛋白对HUVEC迁移能力的影响;鸡胚绒毛尿囊膜(CAM)实验观察Arresten蛋白对新生血管的抑制情况。结果:原核表达的Arresten蛋白纯化品能特异性地抑制 HUVEC的增殖、迁移,诱导HUVEC的凋亡,并在一定范围内呈现出剂量—效应关系。Arresten蛋白能有效抑制鸡胚尿囊膜血管的生长(P<0.01)。结论:原核表达的Arresten蛋白纯化品对内皮细胞有特异的抑制作用,能有效抑制血管生成。     

羟基红花黄色素A抑制PDGF促大鼠血管平滑肌细胞增殖的作用

羟基红花黄色素A是从活血化瘀中草药红花中分离出来的黄酮类化合物,研究发现其对心血管疾病具有很好的治疗作用,但该化合物对血管增生性疾病的防治机理还不清楚。该研究通过采用大鼠血管平滑肌细胞(vascular smooth muscle cells,VSMCs)培养、MTT分析、Western blot、免疫组织化学等方法研究羟基红花黄色素A对VSMCs增殖的影响及其作用机制。实验结果表明,羟基红花黄色素A浓度依赖性地抑制血小板源生长因子(platelet-derived growth factor,PDGF)诱导的VSMCs增殖,降低增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)的表达,阻断PDGF受体的激活和MEK/ERK信号通路的活化。该研究证实,羟基红花黄色素A通过降低PCNA表达和阻断MEK/ERK1/2信号通路抑制大鼠血管平滑肌细胞的增殖。     

以CAM为活性导向快速分离抑制血管新生活性成分

采用鸡胚尿囊膜模型(CAM),对云南鼠尾草和丹参两种植物抑制血管新生活性部位进行筛选,继而,将活性部位采用硅胶柱层析、凝胶柱色谱及其他分离手段做进一步的分离纯化,根据化合物理化性质和波谱数据对其进行结构鉴定,并用CAM模型对化合物做活性评价,结果从5个活性部位分离得到5个具有较强抑制血管新生作用的化合物:丹参酮ⅡA(1)、丹参内酯(2)、丹参酮Ⅰ(3)、隐丹参酮(4)、柳杉醇(7),其中化合物2和7首次发现具有抑制血管新生活性。     

96种中药单体抑制血管生成的活性研究

采用内皮细胞高通量筛选模型和鸡胚尿囊膜(CAM)实验筛选技术,分析96种中药单体的抑制血管生成的活性。筛选结果表明有11种中药单体对Eahy-926细胞的增殖有一定的抑制作用且呈剂量依赖关系,有10种中药单体具有抑制CAM血管形成的作用。秦皮素、汉防己甲素、和厚朴酚、蝙蝠葛碱、鲁斯可皂苷元、高粱姜素、染料木素、隐绿原酸、齐墩果酸和α-倒捻子素,这10种单体化合物值得进一步研究。     

缺血性心脏病患者血清对血管内皮细胞增殖的影响

目的:探讨不同阶段缺血性心脏病患者血清对人脐静脉血管内皮细胞(HUVEC)增殖的影响。方法:采集正常健康人群组(A组)、缺血性心脏病高危人群组(B组)、缺血性心脏病急性期患者组(C组)、缺血性心脏病稳定期患者(D组)的血清,分别作用于人脐静脉血管内皮细胞不同时间,通过MTT比色法,检测细胞的生长抑制率,观察其对HUVEC增殖的影响。结果:四组血清处理HUVEC 24、48、72、96小时后,B组、C组和D组的细胞生长抑制率均显著低于A组(P0.05),且C组和D组24小时的生长抑制率显著低于B组(P0.05),D组48、96小时显著低于B组(P0.05),D组96小时显著低于C组(P0.05)。随着观察时间的延长,A、B、C组患者血清的促增殖作用逐渐增强,48 h、72 h和96 h的生长抑制率均显著低于同组24 h(P0.05);A组患者血清培养至96 h,生长抑制率与同组48 h比较显著降低(P0.05)。结论:从高危患者发展至缺血性心脏病,以及心血管疾病在度过急性期后,随着病程和生存期的延长,其血清对细胞的促增殖作用逐渐增强。     

海参皂苷Des-echinoside A通过NF-κB信号通路抑制人肺巨细胞癌95D细胞转移

采用高速逆流色谱法从革皮氏海参中分离纯化得到皂苷单体Des-echinoside A,研究了Des-echinoside A对高转移人肺巨细胞癌95D细胞增殖和转移的影响及其分子机制。结果显示:Des-echinoside A能显著降低95D细胞增殖(P0.01)、迁移(P0.01)、侵袭(P0.01)以及粘附能力(P0.01);还能显著抑制鸡胚尿囊膜(chick embryo chorioallantoic membrane,CAM)上的血管新生。Des-echinoside A能显著降低u PA、MMP-2/-9、VEGF和NF-κB mRNA的表达(P0.05,P0.01),显著上调TIMP-1/-2 mRNA的表达(P0.01),提示Desechinoside A可能通过调控NF-κB信号通路抑制95D细胞转移。     

白芨中萜类化合物通过诱导血管内皮细胞凋亡抑制血管生成

本文研究了白芨中的萜类化合物对血管生成的抑制作用．及其抑制血管生成的可能机制。采用萃取和色谱法从白芨中分离和纯化了该萜类化合物。通过鸡胚绒毛囊膜（CAM）和人脐静脉内皮细胞（HUVEC）研究了白芨中萜类化合物及其粗提物对血管及血管内皮细胞的抑制作用。结果表明,含该萜类的粗提物显著抑制鸡胚绒毛尿囊膜血管生成;该萜类纯品能明显抑制HUVEC增殖,且可诱导HUVEC凋亡,包括细胞体积缩小,细胞膜起泡,细胞核裂解,染色质浓缩和边集,出现凋亡小体,DNA降解。因此．白芨萜类化合物的抗血管生成作用与诱导血管内皮细胞凋亡有关。     

云南昭通年青褐煤黄腐酸钠对血管新生作用的影响

研究云南昭通地区年青褐煤黄腐酸钠对体内外血管新生作用的影响。将不同浓度的黄腐酸钠作用于人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)体外模型和鸡胚绒毛尿囊膜(chick chorioallantoic membrane,CAM)体内模型,采用MTT和划痕法检测其对HUVECs增殖和迁移的影响,以ELISA试剂盒测定细胞上清液血管内皮生长因子(vascular endothelial growth factor,VEGF)的表达,采集CAM图片用Image-Pro Plus6.0软件考察给药区域血管新生的情况。结果显示,与对照组比较,云南昭通年青褐煤黄腐酸钠在100、200、400μg/m L的浓度下对HUVECs的增殖有抑制作用(P0.05,P0.01),在100、200μg/m L浓度时对迁移有抑制作用并能下调血管内皮生长因子VEGF的表达(P0.01),在高浓度800、1200μg/m L下能抑制CAM血管的新生(P0.05)。研究结果表明,云南昭通地区年青褐煤黄腐酸钠具有良好的血管新生抑制作用,其机制可能与生长因子VEGF表达的下调有关。     

平阳霉素对鸡胚绒毛尿囊膜血管内皮细胞生长的影响

利用鸡胚绒毛尿囊膜研究平阳霉素对血管内皮细胞移动和增殖的影响.(1)内皮细胞移动采用组织学切片、常规H-E染色,通过观察不同胚龄鸡胚CAM的组织学结构即可判定毛细血管EC移动.发现鸡胚在第8、10、12天胚龄时CAM EC都位于外胚层绒毛膜上皮之下,随胚龄增大,EC逐渐由中胚层移向外胚层.而孵育至第14天后(16、18天)CAM毛细血管EC大都移至外胚层上皮之上,紧贴壳膜.PY可明显抑制EC移动,使第18天胚龄时早已该移至外胚层之上的毛细血管EC仍停留在外胚层上皮之下.(2)内皮细胞增殖用放射自显影技术对第10天胚龄的鸡胚CAM EC进行3H-TdR标记,标记率即反映EC增殖的程度.同时用血管生长抑制剂PY对比研究对EC增殖的影响.对照组和实验组EC 3H-TdR标记率分别为41.5±3.4%和20.3±1.5%,PY可使CAM EC的DNA合成减少,即抑制EC增殖.鸡胚CAM可作为研究EC移动和增殖的体内模型,用于血管生成刺激因子和抑制因子的筛选和研究.     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.