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41.
In an attempt to improve immune responses and protective efficacy, we constructed two recombinant bacille Calmette-Guérin (rBCG) strains expressing an 85B antigen (Ag85B) and early secreted antigenic target-6 kDa antigen (ESAT6) of Mycobacterium tuberculosis (MTB) fusion protein. Both rBCG strains have the same protein insertion but in a different order (Ag85B-ESAT6 and ESAT6-Ag85B). The cultured supernatant of rBCG strains and the sera from the mice immunized with the fusion protein Ag85B- ESAT6 or ESAT6-Ag85B formed a band with a fraction size of 37 kDa, equalivalent to the sum of Ag85B and ESAT6. Six weeks after BALB/c mice were immunized with BCG or rBCG, spleen lymphocytes showed significant proliferation in response to culture filtrate protein of MTB. Compared with the BCG group, mice vaccinated with rBCG elicited a high level increase of immunoglobulin G antibodies to culture filtrate protein in the serum. The T-interferon levels in the lymphocyte culture medium supernatants increased remarkably in the rBCG1 group, significantly higher than that of the BCG immunized group (P〈0.05). Four weeks after vaccination, mice were infected with M. tuberculosis H37Rv and a dramatic reduction in the numbers of MTB colony forming units in the spleens and lungs was observed in the two rBCG immunization groups. Although these rBCG strains were more immunogenic, their protective effect was comparable to the classical BCG strain, and there were no significant differences between two rBCG groups (p〉0.05).  相似文献   
42.
Cytoplasmic dynein is the most important molecular motor driving the movement of a wide range of cargoes towards the minus ends of microtubules.As a molecular motor protein,dynein performs a variety of basic cellular functions including organelle transport and centrosome assembly.In the nervous system,dynein has been demonstrated to be responsible for axonal retrograde transport.Many studies have revealed direct or indirect evidence of dynein in neurodegenerative diseases such as amyotrophic lateral sclerosis,Charcot-Marie-Tooth disease,Alzheimer’s disease,Parkinson’s disease and Huntington’s disease.Among them,a number of mutant proteins involved in various neurodegenerative diseases interact with dynein.Axonal transport disruption is presented as a common feature occurring in neurodegenerative diseases.Dynein heavy chain mutant mice also show features of neurodegenerative diseases.Moreover,defects of dynein-dependent processes such as autophagy or clearance of aggregation-prone proteins are found in most of these diseases.Lines of evidence have also shown that dynein is associated with neurodevelopmental diseases.In this review,we focus on dynein involvement in different neurological diseases and discuss potential underlying mechanisms.  相似文献   
43.
The TK-selected chromosome-mediate gene transferlines were analysed using DNA dot blot method,G-11banding and in situ hybridization.The results showedthat CMGT can provide a wide variety of intermediatesize of the transgenome from greater than 80,000kb toless than 2,000kb.Some of transfectants are intergratedinto mouse chromosome which can be detected by G-11banding and in situ hybridization  相似文献   
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The protein prenylation is one of the essential post-translational protein modifications, which extensively exists in the eukaryocyte. It includes protein farnesylation and geranylgeranylation, using farnesyl pyrophosphate(FPP) or geranylgeranyl pyrophosphate(GGPP) as the substrate, respectively. The prenylation occurs by covalent addition of these two types of isoprenoids to cysteine residues at or near the carboxyl terminus of the proteins that possess Caa X motif, such as Ras small GTPase family. The attachment of hydrophobic prenyl groups can anchor the proteins to intracellular membranes and trigger downstream cell signaling pathway. Geranylgeranyl biphosphate synthase(GGPPS) catalyzes the synthesis of 20-carbon GGPP from 15-carbon FPP. The abnormal expression of this enzyme will affect the relative content of FPP and GGPP, and thus disrupts the balance between protein farnesylation and geranylgeranylation, which participates into various aspects of cellular physiology and pathology. In this paper, we mainly review the property of this important protein post-translational modification and research progress in its regulation of cigarette smoke induced pulmonary disease, adipocyte insulin sensitivity, the inflammation response of Sertoli cells, the hepatic lipogenesis and the cardiac hypertrophy.  相似文献   
46.
The respiration metabolismand excretion of marinebivalves were studied by different researchers[1—6].Themetabolic rate of bivalves is influenced by a number ofvariables,includingtemperature,body size,oxygen ten-sion,food concentration,reproductive state,activityleveland physiological condition.The excreted metabolites ofbivalves include ammonia,urea,uric acid and others,with ammonia comprising70%of the total excretion.Solenaia oleivorais a proper freshwater bivalve in China.For the consumer it has the follo...  相似文献   
47.
Sodium channel gene expression in mosquitoes, Aeries albopictus (S.)   总被引:1,自引:0,他引:1  
A mosquito strain of Aedes albopictus, HAmAal^G0, from Huntsville, Alabama, USA, showed a normal susceptibility and low tolerance to permethrin and resmethrin (pyrethroid insecticides) compared to a susceptible Ikaken strain, even though these pyrethroid insecticides have been used in the field for a long period of time in Alabama. Recently, we treated HAmAal^G0 in the laboratory with permethrin for five generations and detected no significant change in the level of resistance to permethrin in the selected mosquitoes, HAmAal^G0, compared with the parental strain HAmAal^G0. We then examined the allelic expression at the L-to-F kdr site of the sodium channel gene in the Aedes mosquitoes to address our hypothesis that the L-to-F kdr mutation was not present in HAmAal^G0 and HAmAal^G5 mosquitoes. We found that every tested individual in Ikaken, HAmAal^G5, and HAmAal^G5 populations expressed a codon of CTA at the L-to-F kdr site encoding Leu, strongly corresponding to their susceptibility to insecticides.  相似文献   
48.
从新生儿脐血和成人骨髓中分选出造血干/祖细胞(HSC/HPC),构建成cDNA文库,对其进行大规模表达序列标签(EST)测序,通过生物信息学等手段分析基因表达谱,并进行新基因的全长cDNA克隆。在所测的10512条可分析E ST序列中,有9866条来自脐血CD34+|细胞,其中4697条(47.6%)为已知基因,2603条(26.4%)为已知EST,1415条(14.3%)代表未知EST。在已知基因中,8.2%基因与造血相关,22.7%涉及细胞代谢、结构和迁移,13.0%与细胞分裂和防御相关,26.2%与RNA、蛋白质的合成相关,10.6%和细胞信号传递有关。对一些已知和未知的EST,综合测序、生物信息学等方法,进行全长克隆,已获得23个新基因的全长cDNA。 Abstract:Hematopoietic stem/progenitor cells were isolated from umbilical cord blood and adult bone marrow,and subject to cDNA library construction.The gene expression pattern in CD34+ cells and the identification and cloning of novel genes were performed by sequencing ESTs and analyzing them with the tools of bioinformatics.Among the obtained 10 512 ESTs which could be further analyzed,9,866 were from umbilical cord blood where 4 697(67.6%)were known genes,2 603(26.4%)were known ESTs and 1415(14.3%)represented novel ESTs.Within the identified genes,8.2% was involved in hematopoiesis,22.7% was associated with cell metabolism,structure and mobility,13.0% was linked to cell division and defence,26.2% was related to RNA protein synthesis and 10.6% was related with cell signal transduction.In parallel,we developed an efficient working system combining sequencing,bioinformatics,etc.and obtained 23 full-length cDNAs from both known and novel ESTs identified in this work.  相似文献   
49.
对象、方法与结果 1989年4-12月,对南京市城区200对来院建卡的孕妇及其配偶,取外周血制备染色体,G显带分析,每例计数39个中期分裂相,分析3个核型.200对夫妇中发现6对夫妇之一方染色体异常(见表1).其余196对核型正常。对该6例的子女进了随访及染色体分析,结果见表1。  相似文献   
50.
INTRODUCTIONProtoplastcultureis0neofthen1ostrapidlydevel0pingareasinp1anttissueculture,becauseofitsimportancei11plantgeneticmanipulation.However,sofar,thereareonlyafewforesttreespeciesinwhichplantregenerationfr0mprotoplastshaJsbeensuccessful,namelyLiriode…  相似文献   
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