中国人前列腺癌VEGF-C mRNA、VEGFR-3和CD31表达与肿瘤转移的关系

研究前列腺癌组织VEGF-C mRNA、VEGFR-3和CD31的表达与前列腺癌中血管、淋巴管的生成及肿瘤转移的关系。取34例前列腺癌组织和12例癌周正常组织标本,应用原位杂交法检测VEGF-C mRNA表达,并经VEGFR-3和CD31免疫组织化学标记及图像分析,采用Weidner最高血管密度计数法,计数癌组织中阳性淋巴管数(MLC)和微血管密度(MVD)。前列腺癌VEGF-C mRNA阳性15例(44.12%),VEGF-C mRNA表达与前列腺癌淋巴结转移、TNM分期相关;MLC (8.26±2.73/mm~2)和MVD(74.82±11.76/mm~2)显著高于癌周正常组织的MLC(4.82±3.48/mm~2)和MVD(32.86±5.41/mm~2),两者比较具有显著性差异。VEGFR-3和CD31表达之间存在正相关。有淋巴转移和TNM分期Ⅲ、Ⅳ期的前列腺癌患者VEGF-C mRNA阳性表达和MLC、MVD分别高于无淋巴转移和Ⅰ、Ⅱ期患者,均具有显著性差异;VEGF-C mRNA表达阳性者VEGFR-3和CD31高于表达阴性者,两者比较具有显著性差异;前列腺癌在不同的组织学分级的差异无统计学意义。VEGF-C促进了肿瘤诱导的淋巴管新生和血管新生,在前列腺癌的淋巴转移中起重要作用;前列腺癌组织中的VEGFR-3和CD31表达水平与肿瘤的转移密切相关;前列腺癌组织MLC和MVD的显著增高,提示肿瘤组织有新淋巴管和血管的生成,也可作为判断肿瘤转移的生物学指标。     

鱼腥藻PCC7120藻蓝蛋白α亚基体内重组研究

为了研究藻蓝蛋白α亚基的生物合成途径,通过构建相容的3种重组质粒pETDuet-cpcA、pCOLADuet-cpcE-cpcF和pACYCDuet-ho1-pcyA,将裂合酶基因cpcE和cpcF、血红素氧化酶基因ho1、藻蓝胆素合成酶基因pcyA和脱辅基藻蓝蛋白α亚基基因cpcA共同转入大肠杆菌BL21(DE3)。通过色素蛋白锌电泳和光谱检测表明产生了生物活性的CpcA-PCB。成功实现了大肠杆菌内藻蓝蛋白α亚基84位半胱氨酸残基与PCB的连接。而在裂合酶基因cpcE和cpcF不转入大肠杆菌的情况下,大肠杆菌内只有0.2%的CpcA-PCB产生。以上研究为进一步在大肠杆菌内合成天然的藻蓝蛋白奠定了基础。     

美洲黑杨次生维管组织发育的内在节律性与细胞内含物的动态变化

美洲黑杨（Populus deltoids）是一种重要的商业用材树种,在我国多用作胶合板和纸浆原料,其速生性的特点也很早为人们所认识。众所周知,树木次生维管组织的发育具有内在的节律性,与此同时维管组织的细胞内含物也会发生动态变化。利用电镜技术及细胞化学方法,研究了美洲黑杨次生维管组织的发育以及细胞内含物分布的变化,发现次生维管组织的发育具有内在节律性,在年周期中表现为分化期和休眠期交替出现,次生韧皮部与次生木质部交替分化形成。在维管组织发育过程中,早期蛋白质和脂类物质首先减少,然后淀粉粒解体消失,发育期内维管组织的蛋白质、脂类和淀粉的积累最少,休眠期内维管组织细胞内最早出现淀粉的积累,然后蛋白质和脂类物质积累大大增加。杨树维管组织发育过程的内在节律性与细胞内含物的动态变化密切相关。     

大鼠初级感觉神经元P2X3受体的表达及其与SP的关系

目的研究在大鼠初级感觉神经元细胞上P2X3受体的表达情况及其与P物质的关系。方法取SD大鼠背根神经节(DRG)和三叉神经节(TG)固定后切片;用抗P2X3受体抗体和抗SP抗体进行免疫组织化学反应,并通过两种不同的显色方法同时进行P2X3受体和SP的双标。结果P2X3免疫反应阳性细胞主要集中在小细胞和中等细胞(其中在TG,P2X3-ir阳性神经元约占整个细胞的24.8%;在DRG约31.7%的神经元是P2X3-ir阳性),并且在DRG和TG细胞上均存在有P2X3受体和SP共存(TG上的双标细胞占P2X3-ir阳性细胞总数的36.26%,DRG上占46.81%)。结论由于ATP门控阳离子通道受体P2X3本身就与伤害性感受的初级传入有关,而它与SP的共存可提示当组织中的ATP释放时可以通过P2X3受体作用于含SP的伤害性感觉神经末梢上,促使SP释放引起痛觉过敏。     

新构建的含DF3启动子和白喉毒素A片段的重组表达载体对人乳腺癌细胞的特异性杀伤作用

目的研究新构建的含人乳腺癌DF3启动子和白喉毒素A片段的重组表达载体PGL3-DF3-DTA对人乳腺癌细胞的影响。方法构建重组表达载体PGL3-DF3-DTA,并用其转染DF3阳性和阴性的乳腺癌细胞MCF-7和MDA-MB-231。通过MTT法测定PGL3-DF3-DTA在体外对乳腺癌细胞生长的影响,建立裸鼠动物模型观察PGL3-DF3-DTA在体内对乳腺癌细胞的杀伤效应。结果成功构建出重组表达载体PGL3-DF3-DTA并建立了人乳腺癌裸鼠动物模型,经重组表达载体PGL3-DF3-DTA作用后的DF3阳性人乳腺癌细胞出现明显的凋亡现象,Ki-67、bcl-2基因表达水平降低,bax基因表达水平升高。结论重组表达载体PGL3-DF3-DTA能对DF3阳性的乳腺癌细胞产生特异性杀伤作用。     

Morphology and Phase Behavior of Two-Component Lipid Membranes

The stability and shapes of domains with different bending rigidities in lipid membranes are investigated. These domains can be formed from the inclusion of an impurity in a lipid membrane or from the phase separation within the membrane. We show that, for weak line tensions, surface tensions and finite spontaneous curvatures, an equilibrium phase of protruding circular domains or striped domains may be obtained. We also predict a possible phase transition between the investigated morphologies.     

A new strain, Streptomyces venezuelae GY1, producing a poly(vinyl alcohol)-degrading enzyme

Summary An actinomycete strain, which could produce an extracellular poly(vinyl alcohol) (PVA)-degrading enzyme, was isolated from a PVA-contaminated soil sample using PVA as the sole carbon source. The strain was identified as Streptomyces venezuelae according to the whole-nucleotide-sequence analysis of 16S rDNA, the morphological and the physiological characteristics. The strain produced 120 U/l extracellular PVA-degrading enzyme when PVA was used as the sole carbon source. When glucose was used as the sole carbon source, however, the extracellular enzyme activity was very low (12 U/l). This is the first report showing that an actinomycete strain can produce a PVA-degrading enzyme.     

In vivo anti-osteoporotic activity of isotaxiresinol, a lignan from wood of Taxus yunnanensis

Isotaxiresinol, the main lignan isolated from the water extract of wood of Taxus yunnanensis, was investigated for its effect on bone loss, on serum biochemical markers for bone remodeling and on uterine tissue, using ovariectomized (OVX) rats as the model of postmenopausal osteoporosis. After oral administration of isotaxiresinol (50 and 100mg/kg/d) for 6 weeks, bone mineral content (BMC) and bone mineral density (BMD) in total and cortical bones were increased as compared to those of OVX control rats, and decreases of three bone strength indexes induced by OVX surgery were prevented. Serum biochemical markers for bone remodeling revealed that isotaxiresinol slightly increased bone formation and significantly inhibited bone resorption without side effect on uterine tissue. These results suggest that isotaxiresinol may be useful for treatment of postmenopausal osteoporosis, especially for prevention of bone fracture induced by estrogen deficiency.     

Characterization and function analysis of a cold-induced AmCIP gene encoding a dehydrin-like protein in Ammopiptanthus mongolicus.

A cDNA clone was isolated after difference screening from cotyledons of two-week cold-treated Ammopiptanthus mongolicus. The full-length cDNA sequence [designated as AmCIP (A. mongolicus cold-induced protein) gene] was 806 bp long and contained a 465 bp open reading frame (ORF) encoding a 16.6 kD protein of 154 amino acids. Bioinformatic analyses indicated that CIP belongs to dehydrin family with the features of high hydrophilicity, a helix K-segment, a long Gly-rich region and a phosphorylatable tract of Ser as well as deficiency in Cys and Trp. The expression of CIP gene increased after two weeks of cold treatment and more expression was detected in radicle than in cotyledon. And PCR amplification of the AmCIP gene from genome of A. mongolicus revealed this gene has no intron. Function prediction suggested this protein seems to protect the stabilization of membrane structure and prevent macromolecular coagulation or sequestrate calcium ions by association or disassociation with membrane under low temperature conditions.     

Levels of Hexachlorocyclohexanes and Dichloro-Dipheny-Trichloroethanes in Penguin Droppings Collected from Ardley Island,Maritime Antarctic

This article reports the concentrations of hexachlorocyclohexanes (HCHs) and dichloro-diphenyl-trichloroethanes (DDTs) in fresh Gentoo penguin (Pygoscelis Papua) droppings deposited on the Ardley Island (62°13′S, 58°56′W), West Antarctica, and those in the island's two lake cores. In the fresh penguin droppings, metabolites were the predominant constituents of the DDT group, most likely due to the ban on DDT use in agriculture and the higher stability of the metabolites in the environment. In contrast, γ-HCH comprised 66% of the total HCHs, apparently due to the continuous use of Lindane in the Southern Hemisphere. The concentrations of HCHs and DDTs in the fresh droppings are many times higher than those in penguin plume, the latter currently being used as biomaterial for monitoring coastal contaminations in Antarctica. Results of this study indicate that penguin droppings have a good potential for use as another biomonitoring material in detecting the organochlorine pesticides and other contaminants in the maritime Antarctic. Because penguin droppings can be well preserved in lake sediments, they also provide a good and continuous historical record of these contaminants. The slight increase of DDTs since the 1990s, as observed in the aged penguin droppings in the sediment cores, suggests there have been new inputs of DDT into the Antarctic coastal ecosystem, probably from the illegal use of DDT in the Southern Hemisphere.