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61.
利用mtCOI PCR-RFLP技术鉴定中国境内九个烟粉虱隐种 总被引:1,自引:0,他引:1
烟粉虱Bemisia tabaci (Gennadius)是一个物种复合体, 包括31个以上形态上无法区分的隐种, 其中少数隐种是世界性入侵害虫。目前, 在中国境内分布有2个入侵隐种和13个土著隐种。快速、 高效的鉴别方法对掌握烟粉虱田间发生规律及制定相关防控策略具有重要意义。然而到目前为止, 除了mtCOI基因测序比对外, 尚未有一种简便的方法可以有效地区分多个烟粉虱隐种。本研究采用mtCOI PCR-RFLP技术, 单独或组合使用TaqI, VspI, Van91I, NcoI和FokI这5种限制性内切酶, 酶切烟粉虱mtCOI的PCR扩增片段, 鉴别分布在中国境内的9个烟粉虱隐种。结果表明, 单独使用TaqI酶切, 可鉴别出MEAM1和China 1两个隐种, 使用TaqI+NcoI分步酶切可鉴定出MED和Asia 1两个隐种, 使用TaqI+Van91I分步酶切可鉴定出Asia II 3和Asia II 9两个隐种, 使用TaqI+VspI+FokI分步酶切可鉴定出Asia II 1, Asia II 6和Asia II 7 3个隐种。本研究为高效鉴别中国境内的多个烟粉虱隐种提供了方法。 相似文献
62.
Tianjiao Lyu Nan Jia Jieyu Wang Xiaohui Yan Yinhua Yu Zhen Lu Robert C Bast Jr Keqin Hua Weiwei Feng 《Epigenetics》2013,8(12):1330-1346
The initiation of angiogenesis can mark the transition from tumor dormancy to active growth and recurrence. Mechanisms that regulate recurrence in human cancers are poorly understood, in part because of the absence of relevant models. The induction of ARHI (DIRAS3) induces dormancy and autophagy in human ovarian cancer xenografts but produces autophagic cell death in culture. The addition of VEGF to cultures maintains the viability of dormant autophagic cancer cells, thereby permitting active growth when ARHI is downregulated, which mimics the “recurrence” of growth in xenografts. Two inducible ovarian cancer cell lines, SKOv3-ARHI and Hey-ARHI, were used. The expression level of angiogenesis factors was evaluated by real-time PCR, immunohistochemistry, immunocytochemistry and western blot; their epigenetic regulation was measured by bisulfite sequencing and chromatin immunoprecipitation. Six of the 15 angiogenesis factors were upregulated in dormant cancer cells (tissue inhibitor of metalloproteinases-3, TIMP3; thrombospondin-1, TSP1; angiopoietin-1; angiopoietin-2; angiopoietin-4; E-cadherin, CDH1). We found that TIMP3 and CDH1 expression was regulated epigenetically and was related inversely to the DNA methylation of their promoters in cell cultures and in xenografts. Increased H3K9 acetylation was associated with higher TIMP3 expression in dormant SKOv3-ARHI cells, while decreased H3K27me3 resulted in the upregulation of TIMP3 in dormant Hey-ARHI cells. Elevated CDH1 expression during dormancy was associated with an increase in both H3K4me3 and H3K9Ac in two cell lines. CpG demethylating agents and/or histone deacetylase inhibitors inhibited the re-growth of dormant cancer cells, which was associated with the re-expression of anti-angiogenic genes. The expression of the anti-angiogenic genes TIMP3 and CDH1 is elevated during dormancy and is reduced during the transition to active growth by changes in DNA methylation and histone modification. 相似文献
63.
64.
PEG1基因影响动物胚胎生长及母性行为,多数动物PEG1为父方表达的遗传印记特征,但出生后猪的PEG1印记表达尚不清楚。因此,文章选取长白、大白和蓝塘3个品种共166头纯种猪,在猪的PEG1基因外显子12区域内寻找SNP,采用PCR-SSCP方法对其多态性进行检测和基因频率分析;取带有PEG1基因该位点SNP为杂合的仔猪3头,对其胃、胸腺、胰、脾、肺、肌肉、肝、舌、肾、脑、膀胱、心脏等组织器官和胎盘的mRNA产物分别进行RT-PCR-SSCP分析,结果表明:PEG1基因外显子12存在一个由G突变为A的单核苷酸多态性位点;PEG1的外显子12在3头仔猪的主要组织器官仅表达父亲来源的等位基因,表明猪的PEG1基因呈母方印记、父方表达的遗传特征。 相似文献
65.
Larsen KO Yndestad A Sjaastad I Løberg EM Goverud IL Halvorsen B Jia J Andreassen AK Husberg C Jonasson S Lipp M Christensen G Aukrust P Skjønsberg OH 《American journal of physiology. Lung cellular and molecular physiology》2011,301(1):L50-L59
The chemokine receptor CCR7 regulates lymphocyte trafficking, and CCR7 deficiency induces infiltration of T and B cells adjacent to vessels in mouse lungs. Perivascular infiltration of T and B cells has also been found in human pulmonary arterial hypertension, and downregulation of the CCR7 receptor in circulating leukocytes of such patients has been observed. To investigate whether changes in the CCR7 system contribute to the pathogenesis of pulmonary hypertension, we utilized mice deficient of the CCR7 receptor. The cardiopulmonary and inflammatory responses of CCR7 depletion were evaluated in CCR7-deficient and wild-type mice. Measurements of cytokines upregulated in the animal model were also performed in patients with pulmonary hypertension and controls and in vascular smooth muscle cells. We found that mice lacking CCR7 had increased right ventricular systolic pressure, reduced pulmonary artery acceleration time, increased right ventricular/tibial length ratio, Rho kinase-mediated pulmonary vasoconstriction, and increased muscularization of distal arteries, indicating pulmonary hypertension. These mice also showed increased perivascular infiltration of leukocytes, consisting mainly of T and B cells, and increased mRNA levels of the inflammatory cytokines interleukin-12 and CX3CL1 within pulmonary tissue. Increased serum levels of interleukin-12 and CX3CL1 were also observed in patients with pulmonary hypertension, particularly in those with pulmonary hypertension associated with connective tissue disorder. In smooth muscle cells, interleukin-12 induced secretion of the angiogenic cytokine interleukin-8. We conclude that these results suggest a role for CCR7 in the development of pulmonary arterial hypertension, at least in some subgroups, possibly via pulmonary infiltration of lymphocytes and secretion of interleukin-12 and CX3CL1. 相似文献
66.
摘要: 【目的】为了探讨圆唇散白蚁Reticulitermes labralis补充生殖蚁对巢群稳定和发展的作用。【方法】对野外巢群进行调查研究, 及对婚飞成虫通过雌雄配对与补充生殖蚁隔离巢群进行人工饲养的对比研究。【结果】在野外巢群只发现1对原始蚁王蚁后, 而补充生殖蚁的数量最多可达到689头/巢。圆唇散白蚁有3种类型的补充生殖蚁, 即由工蚁转化来的无翅型补充生殖蚁、若蚁转化来的翅芽型补充生殖蚁和末龄若蚁羽化来的拟成虫型补充生殖蚁。实验室条件下婚飞配对群体和隔离群体建群1个月后的存活率分别为64%和96%。建巢初期婚飞配对群体的子代数目增长缓慢, 2个月时的群体数量为6.3±1.54, 10个月时的群体数量也仅为8.4±1.47; 而隔离建群补充生殖蚁2个月时的群体数量为52.4±6.44, 10个月时的群体数量为164.3±20.85, 都高于婚飞配对群体。 此外, 野外巢群的补充蚁后跟原始蚁后一样都具有发达的卵巢。【结论】在圆唇散白蚁中补充生殖蚁是白蚁巢群主要的繁殖力量, 也是建立新巢群的重要繁殖品级。 相似文献
67.
68.
Zhang LX Tong XJ Sun XH Tong L Gao J Jia H Li ZH 《Cellular and molecular neurobiology》2008,28(4):501-509
Objectives To observe the effect of ultrashortwave (USW) therapy on nerve regeneration after acellular nerve allografts(ANA) repairing
the sciatic nerve gap of rats and discuss its acting mechanisms. Methods Sixteen Wistar rats weighing 180–220 g were randomly divided into four groups with four rats in each group: normal control
group; acellular group (ANA, treated by hypotonic-chemical detergent, was applied for bridging a 10 mm-long sciatic nerve
defect); USW group (After 24 h of ANA repairing the sciatic nerve gap, low dose USW was administrated for 7 min, once a day,
20 times a course of treatment, three courses of treatment in all); and autografts group. 12 weeks after operation, a series
of examinations was performed, including electrophysiological methods, the restoring rate of tibialis anterior muscle wet
weight, histopathological observation (myelinated nerve number, myelin sheath thickness, and axon diameter), vascular endothelial
growth factor (VEGF) mRNA expression of spinal cord, and muscle at injury site, and analyzed statistically. Results Compared to acellular nerve allografts alone, USW therapy can increase nerve conductive velocity, the restoring rate of tibialis
anterior muscle wet weight, myelinated nerve number, axon diameter, VEGF mRNA expression of spinal cord, and muscle at injury
site, the difference is significant. There were no differences between USW group and autografts group except myelin sheath
thickness. Conclusions USW therapy can promote nerve axon regeneration and Schwann cells proliferation after ANA repairing the sciatic nerve gap
of rats, the upregulation of VEGF mRNA expression of spinal cord and muscle may play an important role. 相似文献
69.
目前,对胚状体发生过程中的生理生化研究表明,这一过程伴随有核酸、蛋白质等大分子物质合成速度的增加及与胚胎发生有关的特异性蛋白的合成;一些同工酶,如过氧化物酶、脂酶、细胞色素氧化酶和谷氨酸脱氢酶 相似文献