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801.
重组Gallinacin-3的克隆及在大肠杆菌中的表达   总被引:3,自引:0,他引:3  
防御素是昆虫、植物和动物体内抗感染及激发特异性抗感染免疫的重要抗菌肽。Gallinacin-3(gal-3)可能是鸡体内最重要的β-防御素,但它的功能还未得到研究证实。本试验从鸡黏膜表皮组织中克隆了gal-3编码基因,并在大肠杆菌中成功表达了gal-3与谷胱甘肽转硫酶(GST)融合蛋白。经IPTG诱导后,融合蛋白的产量占细菌总蛋白的33.6%左右,主要以包涵体形式存在。用亲合层析技术从大肠杆菌裂解液中纯化出可溶性重组蛋白,并用酶切除目标蛋白的融合伴侣。抑菌试验发现,重组gal-3-GST融合蛋白在未去除融合伴侣时,就与游离的gal-3有着相同的抑菌活性,对沙门氏肠炎杆菌和志贺氏痢疾杆菌的最小杀菌浓度在20μg/mL(相当于约4μg/mL纯gal-3)左右,与其他物种β-防御素的活性相当。  相似文献   
802.
803.
AIM:To investigate the effect of an insulin-degrading enzyme (IDE) activator, iodoacetamide, on an AD rat model. METHODS:Thirty-two male Wistar rats were divided into 4 groups:Aβ group, Aβ+ iodoacetamide group, iodoacetamide group and control. Each group included 8 subjects. Aβ was injected into the CA3 area of bilateral hippocampi;Iodoacetamide was administered subcutaneously daily for 5 consecutive days before surgery. The behavior performance in the morris water maze was obtained. The level of Aβ was detected by immunohistochemistry staining and ELISA assay. RESULTS:Level of Aβ was significantly reduced in Aβ+iodoacetamide group compared with that of Aβ group (dropped by 24%), and the Aβ deposit decreased (by 23.9%), the cognition function of this group also greatly improved according to the behavior performance in the morris water maze. The mean escape latency in the place navigation was much lower compared to Aβ group and the times that rats acrossed the central platform in the spatial probe test was also elevated. CONCLUSION:Iodoacetamide significantly reduces the Aβ deposit in the hippocampus in an AD rat model and relieves memory loss.  相似文献   
804.
805.
AIM:To observe the influence of APP17-mer peptide on the learning and memory,and oxidative stress in mitochondria in hipp ocampal neurons of senescence accelerated mouse/prone 10 (SAMP10).METHODS:The 4-month-old SAMP 10s were randomly divided into mod el group and APP17-mer peptide group (the model group+APP17-mer peptide).The se nescence accelerated mouse/resistance1 (SAMR1) were used for normal control.The APP17-mer peptide group was injected with APP17-mer peptide subcutaneously in a dose of 0.34 μg/per mouse,three times a week;while the model group and the control group were injected with saline.After 28 weeks,water maze test was use d to evaluate the learning and memory of these mice.Then hydroxy lamine reactio n and thiobarbituric acid reaction were used to assay the activity of superoxid e dismutase (SOD) and contents of malondialdehyde (MDA) in mitochondria in hippo campal neurons,respectively.RESULTS:(1) The water maze test showed that the full-course swi mming time and numbers of error committed in model group were significantly incr eased as compared with the normal control (P<0.05).The results in APP17-me r peptide treated group were the same as that in normal control group.(2) Compa red with the normal control,the activity of SOD decreased in model group (P <0.01),and the contents of MDA increased (P<0.01).APP17-mer partially re versed the increase in MDA and the decrease in SOD.The content of MDA was lower and the activity of SOD was higher in APP17-mer peptide group than those in mod el group (P<0.05).CONCLUSION:The learning and memory deficit in SAMP10 are observ ed,and the balance of free radical generation/free radical scavenger is impai red.APP17-mer peptide has an antioxidant character and corrects the abnormal ch ange of SOD and MDA,which may be related to its protective effect of learning and memory.  相似文献   
806.
AIM: To study the effect of supernatants from cord blood mononuclear cells (CBMC) and peripheral blood mononuclear cells (PBMC) on infection of HIV-1 in vitro, and develop effectively soluble factors for human acquired immunodeficiency syndrome (AIDS) treatment. METHODS: Different supernatants from CBMC and PBMC activated by PHA for 5 hours and 12 hours were added to cell culture systems between HIV-1ⅢB/H9 cells labeled by calcein-AM and MT-2 cells, then to count the fusion under a reverted fluorescent microscope after 2 hours, respectively, and different soluble factors in supernatants were detected by Luminex 100TM. RESULTS: These supernatants from CBMC and PBMC activated by PHA for 5 hours and 12 hours inhibited the formation of fusion, and there is no difference between supernatants collected in CBMC and PBMC at same time point. However, the supernatants collected in 5 hours were more effective to inhibit the formation of fusion than those in 12 hours (P<0.05). There was a lower concentration for pro-inflammatory cytokines, such as IFN-γ, MCP-1 and TNF-α, in supernatants from CBMC than those from PBMC, but the concentration of MIP-1a and RANTES in supernatants from CBMC was higher than those from PBMC. CONCLUSION: The soluble factors for anti-HIV can be prepared from CBMC and PBMC, which is a new source of anti-HIV therapeutic preparation.  相似文献   
807.
AIM: To investigate the characterization of absorption of hematoporphyrin monomerthyl ether (HMME), a domestic new generation photosensitizer product, by activated T cells from human peripheral blood. METHODS: Evaluation was performed by flow cytometry on the effects of incubating concentration and time of HMME on absorption by activated T cells. Lymphocytes were separated from human peripheral blood by density gradient centrifugation with Ficoll and T cells were activated with polyclonal stimulators PHA and PDB+Ion. To analyze the effects of HMME incubating doses on the absorption of activated T cells, the cultural lymphocytes were incubated with a serial doses of HMME for 1 h and HMME absorption were measured by FACS after immuno-staining with anti-CD3 antibody. To test the impact of HMME incubating time on the absorption of activated T cells, the cultural lymphocytes were incubated with HMME for various times and HMME absorption were measured by FACS after immuno-staining with anti-CD3 antibody. RESULTS: The HMME absorption-dose curve and absorption-time curve were shifted to right and up in the activated T cells as compared to resting T cells. HMME absorptions of activated T cells were statistic significantly larger than that of resting T cells in the doses between 5 mg/L to 20 mg/L. HMME absorptions of either activated T cells or resting T cells underwent a gradual increase with the incubation-time in HMME at concentration of 10 mg/L. HMME absorptions of activated T cells were statistic significantly larger than that of resting T cells in the incubation-time between 15 to 60 min. CONCLUSION: The differences of HMME absorption between activated T cells and resting T cells depend on the incubation times and doses of HMME. HMME absorption of activated T cells are significantly larger than that of resting T cells in certain incubation-times and doses. These results suggest that incubation time and dose associated with HMME-PDT therapeutic windows will be created for selective deletion of activated T cells.  相似文献   
808.
果实蝇属害虫是国际上备受关注的检疫性有害生物。福州机场截获的疫情数据分析表明,橘小实蝇是我国南方周边国家和地区果实蝇群落结构中的优势种群。传播该虫的主要水果有莲雾、释迦、芒果、火龙果。每年3~11月是该虫的截获高峰期。  相似文献   
809.
草地螟寄生蝇寄生规律及控害作用研究   总被引:2,自引:0,他引:2  
田间调查和室内饲养观察表明,康保县草地螟的寄生蝇主要有伞裙追寄蝇、双斑截尾寄蝇等5种。草地螟寄生蝇一般只寄生幼虫,未见寄生其他虫态。寄生率随草地螟幼虫密度增大、虫龄增长而迅速升高。多年发生资料分析,寄生蝇寄生率高的年份,下年草地螟的发生为害程度明显减轻。  相似文献   
810.
与苹果果皮红色性状相关的RAPD分子标记的筛选   总被引:7,自引:2,他引:7  
用355条10bp随机引物来筛选与苹果果实红色性状连锁的分子标记。通过分离群体分组分析,在果实红色与非红色2个对比基因池间进行了扩增筛选,初步选出49个多态性引物,进一步对这些多态性引物进行群体上的分析发现S519可以扩增出大约1000bp左右的一条与红色性状相关的DNA特异带。对本研究的73个来自3个不同杂交组合的F1后代个体分析表明,该标记判断果实红色性状的符合率为76.7%。鉴于获得的多态性标记对果皮颜色预测的准确率不高的现状,我们采用了双标记组合分析方案,即用S5191000分别与以往获得的3个与果色性状相关的标记(S12891200、S12351000和S21071200)配对组合进行判断,从而使得标记对目标性状预测的正确性大为提高。另外,对总共获得的4个RAPD标记在9个栽培品种上进行了分析,大多数品种的表现与理论一致。  相似文献   
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