新型高载药量姜黄素聚前药两亲分子的制备与抗肿瘤研究

姜黄素具有良好的抗癌活性,但其水溶性差、中性与碱性p H条件下稳定性不足等因素限制其医学应用。另外,聚前药两亲分子(polyprodrug amphiphiles)具有载药量高、水溶性改善、纳米结构调控等优势,在抗肿瘤研究中越来越突显优势。本工作通过缩聚方法成功制备了一种姜黄素的聚前药两亲分子,Poly(Cur-altTEG),具有高载药量,提高了姜黄素的水溶性和稳定性,进一步的细胞毒性实验表明其具有良好的抗肿瘤活性。     

姜黄素与消化系统肿瘤的研究进展

姜黄素是一种疏水多酚,从姜黄中提取的姜黄磺胺类草药。半个世纪以来大量的研究表明姜黄素在体外及体内显示了各种诸如抗炎、细胞活素的释放、抗氧化、免疫调节、促进凋亡以及抗血管生成的特性。姜黄素同样也被证明是耐药性和放疗不敏感性的调解者。同样,在各种临床试验研究中证明了姜黄素抗肿瘤的作用,本文就姜黄素在消化系统肿瘤中的抗肿瘤机制做一综述。     

姜黄素与消化系统肿瘤的研究进展

姜黄素是一种疏水多酚,从姜黄中提取的姜黄磺胺类草药。半个世纪以来大量的研究表明姜黄素在体外及体内显示了各种诸如抗炎、细胞活素的释放、抗氧化、免疫调节、促进凋亡以及抗血管生成的特性。姜黄素同样也被证明是耐药性和放疗不敏感性的调解者。同样,在各种临床试验研究中证明了姜黄素抗肿瘤的作用,本文就姜黄素在消化系统肿瘤中的抗肿瘤机制做一综述。     

姜黄素抗肿瘤作用及机制研究进展

姜黄素是从草本植物姜黄、莪术等根茎中提取的一种植物多酚,有着广泛的药理作用,具有抗心血管疾病、抗肿瘤、抗微生物、抗抑郁、抗炎、抗氧化等生物学功能。抗肿瘤是姜黄素主要生物活性之一,抗肿瘤机制主要有:抑制肿瘤细胞增殖,诱导肿瘤细胞凋亡,抗肿瘤侵袭及转移,逆转肿瘤细胞耐药性及增加对化疗的敏感性等。本文就其抗肿瘤机制的研究进行综述,为姜黄素的进一步开发利用提供基础。     

姜黄素类似物抑制肿瘤细胞增殖的细胞学机制研究进展

姜黄素是一种具有多种生物学效应的天然多酚类物质,但其较低的稳定性和生物利用率等因素限制了其实际临床应用,具有同样类似活性的姜黄素类似物或衍生物目前越来越受到关注。已发现多种化学合成姜黄素类似物小分子能在体外和体内抑制肿瘤细胞增殖,具有潜在的抗肿瘤活性。自噬和凋亡是细胞两种面对外界刺激采取的主动自主行为,近来发现大部分姜黄素类似物小分子能通过诱导自噬或(和)凋亡通路途径引起细胞死亡,该文结合笔者课题组前期研究结果就姜黄素类似物诱导的细胞学机制进行综述,以期为未来有关姜黄素类似物的抗肿瘤药理作用研究提供参考。     

姜黄素诱导肿瘤细胞凋亡的研究进展

姜黄素是从姜科植物的根茎姜黄中提取的一种植物多酚,具有抗炎、抗氧化、抗凝、抗动脉粥样硬化、抗肿瘤等药理作用。本文综述了姜黄素诱导肿瘤细胞凋亡的分子生物学机制研究进展。     

姜黄素衍生物及复合物抗肿瘤的研究

近年来,包括姜黄素、姜黄素衍生物及复合物在内的姜黄家族的抗肿瘤能力已被越来越多的学者所关注,成为现代抗肿瘤研究的热点。姜黄素的去甲氧基化、氨基化、烯酮类、萜烯类等官能团修饰能通过提高姜黄素的水溶性和稳定性,提高其生物利用度,改善药代动力学,增强其抗癌能力。氧钒(vanadyl,IV)复合物、烷氧基联苯/姜黄素偶联物、姜黄素与磺丁基醚-β环糊精包被而成的复合物也均对肿瘤细胞有不同的杀伤抑制作用。现对几年来国内外姜黄素衍生物及复合物抗肿瘤的研究进行总结,旨在为进一步认识姜黄素的抗肿瘤机制,并对姜黄素进行改造提供思路。     

姜黄素抗肿瘤的机制

姜黄素具有很显著的抗肿瘤作用。本文通过对几年来国内外对姜黄素抗肿瘤的研究进行总结,介绍了姜黄素的抗肿瘤机制。在分子水平上,肿瘤细胞摄取姜黄素,增加药物作用的靶位点,调节肿瘤细胞的信号传递,从而调节肿瘤细胞中某些酶活性及蛋白质、基因的表达。在细胞水平上,姜黄素能抑制肿瘤细胞的增殖、促进肿瘤细胞凋亡、逆转肿瘤细胞的多药耐药性、增强NK细胞杀伤力。在组织水平上抑制肿瘤血管生成等方面来发挥抗肿瘤作用。     

姜黄素对COPD抗炎抗氧化作用研究进展

慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)是一种以进行性、不完全可逆性气流受限为主要特征的慢性炎症性肺部疾病。该病是有害气体或颗粒导致肺部异常炎症有关[1]。姜黄素是从姜科植物姜黄中提取的一种酚类化合物,有抗氧化、抗炎、抗肿瘤等作用,近年来研究表明姜黄素对香烟诱导COPD大鼠有抗炎抗氧化作用。     

姜黄素与肿瘤细胞自噬

姜黄素是姜黄中主要的多酚类物质,具有抗炎、抗氧化、抗肿瘤等药理作用,而有关其选择性抗肿瘤作用日渐成为研究热点。姜黄素对肺癌、乳腺癌、肝癌、结直肠癌、恶性胶质瘤、骨肉瘤、白血病等多种恶性肿瘤均具有抑制作用,并且具有良好的生物安全性。自噬是真核细胞应激调控的生物学机制,与肿瘤的发生、发展存在复杂关系。近年来研究证实,姜黄素可通过多种信号通路调控自噬复合体,进而诱导肿瘤细胞自噬,达到抑制细胞生长、促进细胞死亡的作用。本文就姜黄素诱导肿瘤细胞自噬概况及其机制做一综述。     

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.