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101.
CAO Cong ZHAO GuoWei YU Wei XIE XueMin WANG WenTian YANG RuiFeng LV Xiang LIU DePei 《中国科学:生命科学英文版》2014,57(5):488-494
Studies on the chaperone proteinα-hemoglobin stabilizing protein(AHSP)reveal that abundant AHSP in erythroid cells enhance the cells’tolerance to oxidative stress imposed by excessα-hemoglobin in pathological conditions.However,the potential intracellular modulation of AHSP expression itself in response to oxidative stress is still unknown.The present study examined the effect and molecular mechanism of STAT3,an oxidative regulator,on the expression of AHSP.AHSP expression increased in K562 cells upon cytokine IL-6-induced STAT3 activation and decreased in STAT3 knock-down K562 cells.Regulation of AHSP in oxidative circumstance was then examined inα-globin-overloaded K562 cells,and real-time PCR showed strengthened expression of both AHSP and STAT3.ChIP analysis showed binding of STAT3 to AHSP promoter and binding was significantly augmented with IL6 stimulation and uponα-globin overexpression.Dual luciferase reporter assays of the wildtype and mutated SB3 element,an IL-6RE site,in the AHSP promoter in K562 cells highlighted the direct regulatory effect of STAT3 on AHSP gene.Finally,direct binding of STAT3 to SB3 site of AHSP promoter was confirmed with EMSA assays.Our work reveals an adaptive AHSP regulation mediated by the redox-sensitive STAT3 signaling pathway,and provides clues to the therapeutic strategy for AHSP enhancement. 相似文献
102.
湖北地区宫颈癌组织中人乳头瘤病毒16型E7基因的分离、克隆和序列分析 总被引:5,自引:1,他引:5
采用加端聚合酶链反应技术,从湖北地区一宫颈癌患者癌组织DNA中分离出人乳头瘤病毒16型(HPV16)E7基因,并在pUC18载体中克隆。经限制性核酸内切酶分析和DNA序列分析,确认了含HPV16E7重组克隆质粒,命名pHPV16E7─HB。DNA序列分析表明,HPV16E7─HB基因全长294bp(与报道的标准株基因长度相同),但其核苷酸顺序中有两处发生了C→T突变,即第43位密码子CAA变为TAA,第76位CGT变为TGT;前者使谷氨酰胺密码子变为终止密码,即无义奕变(nonsensemutation)。这种突变发生在294个碱基的DNA扩增产物之中,不像是PCR本身的错配,而很可能是湖北株与标准株之间的结构差异。 相似文献
103.
Toshihiko Sudo Xiaoxian Zhao Yoko Wakamatsu Miki Shibahara Nobuhiko Nomura Tadaatsu Nakahara Akemi Suzuki Yoshiro Kobayashi Chunyuan Jin Takehide Murata Kazunari K. Yokoyama 《Cytotechnology》2000,33(1-3):259-264
Four analogs of succinoyl trehalose lipid-3 (STL-3)with saturated even-number or odd-number carbonchains, and unsaturated or halogenated fatty acidswere examined for their ability to inhibit the growthand induce the differentiation of HL-60 humanpromyelocytic leukemia cells. The optimalconcentration of STL-3 at which such activities wererecognized was closed to the critical micelleconcentration of STL-3. Analog of STL-3 witheven-number or odd-number carbon chain and unsaturatedfatty acids strongly inhibited growth and induced thedifferentiation of HL-60 cells, as evaluated in termsof nitroblue tetrazilium-reducing activity and theappearance of the CD36 antigen. An analog of STL-3with halogenated fatty acids significantly inhibitedproliferation but only induced the differentiation ofHL-60 cells. Our results indicate that the effects ofSTL-3 and its analogs on HL-60 cells depend on thestructure of the hydrophobic moiety of STL-3.These authors contributed equally to this work 相似文献
104.
105.
Yanming Sun Ruofeng Yan Charles I. Muleke Guangwei Zhao lixin Xu Xiangrui Li 《International journal of peptide research and therapeutics》2007,13(3):387-392
The effect of Haemonchus contortus galectin peptides rHco-gal-m/f to induce apoptosis in the peripheral blood lymphocytes (PBLCs) of goats was investigated. Analysis of apoptosis was
carried out with agarose gel electrophoresis, flow cytometry and transmission electron microscopy. The results indicated that
there were visible apoptosis bodies and typical DNA ladders by genomic DNA fragmentation. The quantitative analysis of apoptosis
by flow cytometry indicated that rHco-gal-m/f peptides induced apoptosis was time and dose dependent. Ultrastructural studies of the PBLCs revealed that a large
number of apoptotic cells were present in galectin-treated cells, which had the typical morphologic changes of apoptosis such
as reduction of the cytoplasmic volume, loss of cell surface microvilli, chromatin condensation and fragmentation of the apoptotic
cells into small apoptotic bodies. 相似文献
106.
Julien Cappelle Delong Zhao Marius Gilbert Martha I. Nelson Scott H. Newman John Y. Takekawa Nicolas Gaidet Diann J. Prosser Ying Liu Peng Li Yuelong Shu Xiangming Xiao 《EcoHealth》2014,11(1):109-119
For decades, southern China has been considered to be an important source for emerging influenza viruses since key hosts live together in high densities in areas with intensive agriculture. However, the underlying conditions of emergence and spread of avian influenza viruses (AIV) have not been studied in detail, particularly the complex spatiotemporal interplay of viral transmission between wild and domestic ducks, two major actors of AIV epidemiology. In this synthesis, we examine the risks of avian influenza spread in Poyang Lake, an area of intensive free-ranging duck production and large numbers of wild waterfowl. Our synthesis shows that farming of free-grazing domestic ducks is intensive in this area and synchronized with wild duck migration. The presence of juvenile domestic ducks in harvested paddy fields prior to the arrival and departure of migrant ducks in the same fields may amplify the risk of AIV circulation and facilitate the transmission between wild and domestic populations. We provide evidence associating wild ducks migration with the spread of H5N1 in the spring of 2008 from southern China to South Korea, Russia, and Japan, supported by documented wild duck movements and phylogenetic analyses of highly pathogenic avian influenza H5N1 sequences. We suggest that prevention measures based on a modification of agricultural practices may be implemented in these areas to reduce the intensity of AIV transmission between wild and domestic ducks. This would require involving all local stakeholders to discuss feasible and acceptable solutions. 相似文献
107.
以苯乙晴为原料,经水解、氯甲基化、取代、还原四步反应制得盐酸4-(β-氨乙基)苯乙酸。并对文献方法进行了改进。 相似文献
108.
Kim CH Pennisi P Zhao H Yakar S Kaufman JB Iganaki K Shiloach J Scherer PE Quon MJ LeRoith D 《American journal of physiology. Endocrinology and metabolism》2006,291(2):E298-E305
Most rodent models of insulin resistance are accompanied by decreased circulating adiponectin levels. Adiponectin treatment improves the metabolic phenotype by increasing fatty acid oxidation in skeletal muscle and suppressing hepatic glucose production. Muscle IGF-I receptor (IGF-IR)-lysine-arginine (MKR) mice expressing dominant-negative mutant IGF-IRs in skeletal muscle are diabetic with insulin resistance in muscle, liver, and adipose tissue. Adiponectin levels are elevated in MKR mice, suggesting an unusual discordance between insulin resistance and adiponectin responsiveness. Therefore, we investigated the metabolic actions of adiponectin in MKR mice. MKR and ob/ob mice were treated both acutely (28 microg/g) and chronically (for 2 wk) with full-length adiponectin. Acute hypoglycemic effects of adiponectin were evident only in ob/ob mice but not in MKR mice. Chronic adiponectin treatment significantly improved both insulin sensitivity and glucose tolerance in ob/ob but not in MKR mice. Adiponectin receptor mRNA levels and adiponectin-stimulated phosphorylation of AMPK in skeletal muscle and liver were similar among MKR, wild-type, and ob/ob mice. Thus MKR mice are adiponectin resistant despite normal expression of adiponectin receptors and normal AMPK phosphorylation in muscle and liver. MKR mice may be a useful model for dissecting relationships between insulin resistance and adiponectin action in regulation of glucose homeostasis. 相似文献
109.
微生物群落结构探针杂交评价不同培养基从活性污泥分离优势菌群的能力 总被引:8,自引:1,他引:8
用ERICPCR (Enterobacterial Repetitive Intergenic ConsensusPCR)、苯酚羟化酶大亚基基因(LmPHs)扩增和群落结构探针分子杂交检测技术对LB、dCGY、MP和FWM 4种培养基从焦化废水处理厂2个曝气池活性污泥中分离优势功能菌群的能力进行了比较研究。LmPHs扩增显示7种回收菌群中均有以多亚基苯酚羟化酶为代谢途径的苯酚降解菌存在。用代表苯酚降解高峰期活性污泥优势菌组成的总DNA的ERICPCR产物经地高辛标记作为群落结构的混合探针M1和M8,对8种回收菌群的ERICPCR指纹图谱进行杂交检测,不同培养基回收优势菌的能力不同,以废水为基础的FWM培养基从活性污泥中回收到的优势菌种群最多(30.8%~42.9%)。本文建立了用微生物群落结构探针杂交技术对不同培养基回收分离优势菌能力进行评价的方法。 相似文献
110.
Wang LL Chen KP Zhang Z Yao Q Gao GT Zhao Y 《The Journal of eukaryotic microbiology》2006,53(4):310-313
The microsporidian Nosema antheraeae is a pathogen that infects the Chinese oak silkworm, Antheraea pernyi. We sequenced the complete small subunit (SSU) rRNA gene and the internal transcribed spacer (ITS) of N. antheraeae, and compared the SSU rRNA sequences in other microsporidia. The results indicated that Nosema species, including N. antheraeae, formed two distinct clades, consistent with previous observations. Furthermore, N. antheraeae is clustered with N. bombycis with high bootstrap support. The organization of the rRNA gene of N. antheraeae is LSU-ITS1-SSU-ITS2-5S, also following a pattern similar to the Nosema type species, N. bombycis. Thus, N. antheraeae is a Nosema species and has a close relationship to N. bombycis. 相似文献