地鳖虫蛋白提取物对小鼠S180肉瘤及鸡胚尿囊膜血管生成的抑制作用

用不同浓度的地鳖虫蛋白粗提物(0.2~0.8g/ml)作用于S180肉瘤荷瘤小鼠,观察各组的抑瘤效果及重要生理指标的差异;同时分别用地鳖虫蛋白粗提物以及经过盐析、离子交换层析、分子筛由地鳖虫蛋白粗提物分离纯化得到的活性蛋白,作用于鸡胚尿囊膜,观察它们对新生血管生成的抑制作用。结果显示,地鳖虫蛋白粗提物对S180肉瘤荷瘤小鼠有显著的抑瘤作用;蛋白质粗提物以及纯化得到的活性蛋白对鸡胚尿囊膜新生血管的生成有明显的抑制作用,纯化品的抑制活性高于粗品,且二者对鸡胚生长发育的影响较阳性对照(地塞米松组)小,差异显著。因此,地鳖虫蛋白提取物有良好的体内抑瘤作用及血管生成抑制活性。     

自研培养基在人用鸡胚狂犬病疫苗中的应用

目的评估自主研发培养基QS作为首选培养基用于冻干人用狂犬病疫苗(鸡胚成纤维细胞)生产过程的可行性。方法分别制备基于自主研发培养基QS和其他3种商业化培养基(X1、X2、X3)的鸡胚成纤维细胞悬液,观察和比较细胞形态和生长特性;以Flury HEP株接种鸡胚成纤维细胞(MOI=0.003),分别通过直接免疫荧光法、蛋白质印迹法(Western blotting)和酶联免疫吸附测定(enzyme-linked immunosorbent assay, ELISA)比较不同培养基条件下收获液中病毒滴度和G蛋白含量。结果在细胞浓度1×10~6个/mL条件下,4种培养基培养的鸡胚成纤维细胞在形态上均无显著区别;但是自主研发培养基QS和X2的病毒收获液的G蛋白含量在第4天时分别为0.66 IU/mL和0.63 IU/mL,高于X1的0.5 IU/mL和X3的0.3 IU/mL。在第6天时分别为0.92 IU/mL和0.88 IU/mL,高于X1的0.64 IU/mL和X3的0.52 IU/mL,说明基于自主研发培养基QS和X2的病毒收获液在G蛋白含量方面具有明显优势。结论自主研发培养基QS可以用于冻干人用狂犬病疫苗(鸡胚成纤维细胞)的生产。     

双酶法酶解豌豆蛋白制备高抗氧化多肽的研究

以水解度及DPPH自由基清除能力为指标优选出1398中性蛋白酶和胰蛋白酶分步酶解豌豆分离蛋白,所得豌豆蛋白水解产物(pea protein hydrolysate,PPH)中相对分子量小于2 KDa的多肽占77.07％,对DPPH的半清除浓度(IC50)为3.01 mg/mL;PPH经Sephadex G-25凝胶层析和两次RESOURCETM 3RPC反相层析纯化获得高抗氧化活性峰,经反相层析鉴定为层析纯,当浓度在0.2 mg/mL时,对DPPH的清除率达到62.03％,与同浓度下的谷胱甘肽对DPPH的清除率相近(66.82％).     

4种珍稀食用菌水提物的抗氧化活性研究

用DPPH自由基清除法、羟基自由基清除法和超氧阴离子自由基清除法对4种珍稀食用菌灵芝、云芝、茶树菇、松茸的水提物进行抗氧化活性评价,为更好评价其抗氧化活性,以维生素C作为阳性对照。实验结果显示：4种食用菌水提物具有不同程度的抗氧化活性。云芝对DPPH自由基的清除能力最强,其IC₅₀值为1.46 mg/mL,维生素C清除DPPH自由基的IC₅₀为0.046 mg/mL;茶树菇对清除羟基自由基的清除能力最强,其IC₅₀值为1.41 mg/mL,云芝和松茸也有较强清除羟自由基能力,其IC₅₀值分别为1.56、1.57 mg/mL,三者的清除能力均明显优于阳性对照样品,维生素C清除羟自由基的IC₅₀为2.41 mg/mL;灵芝和云芝有较强清除超氧阴离子自由基能力,其IC₅₀值分别为124.48、138.28 mg/mL。     

鸡γ干扰素成熟蛋白基因的表达及其产物抗病毒活性测定

以血淋巴细胞提取的总RNA为模板,通过RT-PCR的方法克隆出鸡干扰素成熟蛋白的基因,把它与非融合表达载体pRLC相重组。通过对阳性宿主菌的不同时间的诱导摸索出最佳表达时间。把表达产物进行变性,复性,纯化后加入鸡胚成纤维细胞上,用水疱性口炎病毒进行攻毒,测出鸡重组干扰素的活性单位为1.0?06U/mL,获得了满意结果。     

鸡α干扰素基因的克隆、原核表达及抗病毒效果研究

通过PCR从三黄肉鸡的肝脏基因组中扩增了鸡α干扰素(ChIFN-α)全长基因。序列分析表明ChIFN-α基因全长582bp,亚克隆其成熟蛋白编码基因(489bp),利用基因重组技术构建了E.coli/pET-28a( )-IFNα,使IFN-α置于pET-28a的T7启动子下游并同6×His(多聚组氨酸标签)-Tag融合。经酶切鉴定,DNA测序证实重组质粒构建正确;将重组质粒转化大肠杆菌BL21(DE3),IPTG诱导表达,SDS-PAGE,Western-blot分析证实表达出22kD左右的融合蛋白,表达的蛋白以不溶性的包涵体形式存在并且具有良好的免疫学活性。提纯的包涵体纯度可达70%以上,用镍亲和层析方法纯化蛋白则可达到95%。经透析复性后的蛋白在鸡胚成纤维细胞上能够抑制H9N2禽流感病毒的复制。鸡胚试验中重组干扰素抗病毒效果好在H9N2禽流感病毒攻毒组中,能保护鸡胚并使其孵出率达到100%的重组干扰素最小蛋白含量为2μg;重组干扰素对新城疫病毒复制也有一定的抑制能力,延迟该病毒复制时间为12h至48h;雏鸡试验表明重组干扰素也能较好地抵抗H9N2禽流感病毒对雏鸡的感染。两组试验均表明,亲和层析纯化蛋白是包涵体蛋白活性的20倍左右。     

盐穗木金属硫蛋白HcMT的体外自由基清除活性及抗氧化能力*

目的: 原核表达盐穗木(Halostachys caspica C. A. Mey.)金属硫蛋白HcMT并探究其抗氧化活性。方法: 构建原核表达载体pET-32a-HcMT,转化至大肠杆菌Escherichia coli BL21,加入Zn²⁺胁迫培养(终浓度为200 μmol/L),分离纯化得到Zn-HcMT,测定Zn-HcMT自由基清除活性和总抗氧化能力,制备复合物Zn-HcMT/TiO₂并做FTIR表征。结果: 通过原核表达获得融合蛋白Zn-HcMT,对·OH、O₂·^-、DPPH自由基具有较强的清除活性,对·OH、O₂·^-的IC₅₀分别为0.386 mg/mL、0.038 mg/mL。融合蛋白浓度为0.01 mg/mL时,对DPPH清除率达(37.43 ± 0.006 8)%,浓度为0.3mg/mL时TEAC(trolox-equivalent antioxidant capacity)值为(1.023 ± 0.01)mmol/L,融合蛋白还原力A₇₀₀为0.142 ± 0.055,FTIR图谱同时表现了Zn-HcMT和TiO₂吸收特性。结论: Zn-HcMT具有良好的清除ROS活性及较强的抗氧化能力,在化妆品领域有潜在应用前景。     

江蓠内生真菌NSS1蛋白活性的初步研究

为促进江蓠内生真菌NSS1抗菌蛋白的应用研究,利用硫酸铵沉淀法制备抗菌蛋白,最佳硫酸铵饱和度为65%。采用滤纸片法检测其对细菌指示菌的抑菌活性,抗菌粗蛋白均能抑制五种细菌指示菌的生长,当浓度达到750 μg/mL时,抑制效果最好。采用邻苯三酚自氧化法测定蛋白对超氧阴离子自由基(O-2)的清除作用,MTT法检测蛋白对肿瘤细胞的影响。抗菌蛋白在100℃以下,pH中性时抑菌活性稳定,对紫外线照射不敏感,丙三醇、甲醇和胰蛋白酶对抗菌蛋白的抑菌活性没有影响。不同浓度的蛋白液对超氧阴离子均有清除效果。当蛋白浓度达到360 μg/mL时对肿瘤细胞的抑瘤作用最强。上述结果显示抗菌蛋白具有较强的抑菌活性、抗氧化活性和抗肿瘤活性。     

鸡胚脑细胞磷脂和能量代谢的模拟微重力生物效应的31P-NMR谱研究

利用31P-NMR方法对回转器旋转的鸡胚脑细胞内磷酸单脂(PME)、磷酸双脂(PDE)及ATP和pH值进行了定量分析, 以研究对脑细胞磷脂代谢及能量代谢的模拟微重力生物效应. 实验结果显示出: 对E13鸡胚旋转24 h引起了ATP和PME及pH值水平的显著性升高. E15鸡胚经24 h旋转对脑细胞磷脂代谢及能量代谢产生类似影响, 但皆未达显著性差异水平. 还利用孔雀石绿方法测量旋转对鸡胚脑细胞 ATPase活性的影响. 从实验结果观察到: E13和E15鸡胚经24 h的旋转引起了ATPase活性的显著下降, 前者比后者更敏感. 停止旋转24 h后, 鸡胚脑细胞所出现的上述变化, 除ATP仍然高于对照外, 其他指标皆可以恢复.     

鸡γ干扰素成熟蛋白基因的表达及其产物抗病毒活性测定

以血淋巴细胞提取的总RNA为模板,通过RT-PCR的方法克隆出鸡γ干扰素成熟蛋白的基因,把它与非融合表达载体pRLC相重组.通过对阳性宿主菌的不同时间的诱导摸索出最佳表达时间.把表达产物进行变性,复性,纯化后加入鸡胚成纤维细胞上,用水疱性口炎病毒进行攻毒,测出鸡重组γ干扰素的活性单位为1.0×106U/mL,获得了满意结果.     

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.