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41.
Interleukin‐35 (IL‐35), a member of the IL‐12 family, functions as a new anti‐inflammatory factor involved in arthritis, psoriasis, inflammatory bowel disease (IBD) and other immune diseases. Although IL‐35 can significantly prevent the development of inflammation in many diseases, there have been no early studies accounting for the role of IL‐35 recombinant protein in IBD and psoriasis. In this study, we assessed the therapeutic potential of IL‐35 recombinant protein in three well‐known mouse models: the dextransulfate sodium (DSS)‐induced colitis mouse model, the keratin14 (K14)‐vascular endothelial growth factor A (VEGF‐A)‐transgenic (Tg) psoriasis mouse model and the imiquimod (IMQ)‐induced psoriasis mouse model. Our results indicated that IL‐35 recombinant protein can slow down the pathologic process in DSS‐induced acute colitis mouse model by decreasing the infiltrations of macrophages, CD4+T and CD8+T cells and by promoting the infiltration of Treg cells. Further analysis demonstrated that IL‐35 recombinant protein may regulate inflammation through promoting the secretion of IL‐10 and inhibiting the expression of pro‐inflammatory cytokines such as IL‐6, TNF‐α and IL‐17 in acute colitis model. In addition, lower dose of IL‐35 recombinant protein could achieve long‐term treatment effects as TNF‐α monoclonal antibody did in the psoriasis mouse. In summary, the remarkable therapeutic effects of IL‐35 recombinant protein in acute colitis and psoriasis mouse models indicated that IL‐35 recombinant protein had a variety of anti‐inflammatory effects and was expected to become an effective candidate drug for the treatment of inflammatory diseases.  相似文献   
42.
含par位点的重组质粒Psjm3的构建及其稳定性研究   总被引:3,自引:0,他引:3  
利用自然质粒pSC101par位点的分离稳定性功能,构建了含par位点的质粒pSJM4和pSJM3,通过在同样宿主E.coli HB101中的稳定性比较研究表明,不含par位点的重组质粒pSJ3很不稳定,E.coli G3(pSJ3)在培养到第10代时已开始出现pSJ3的丢失,到培养至50代时则已全部丢失;而含par位点的重组质粒pSJM3则表现得十分稳定,E.coli G3-1(pSJM3)经70代培养,仍无明显的质粒丢失现象,其稳定率保持97%以上。通过对不含par和含par的非重组质粒pUC18和pSJM4的稳定性比较也获得同样的结果。通过对E.coliG3(pSJ3)和E.coli G3-1(pSJM3)的产酶活性比较研究表明,G3-1菌株明显高于G3菌株,说明我们构建的重组质粒pSJM3上的par位点功能不仅没有因外源基因的表达而受影响,而且有利于外源基因的表达。  相似文献   
43.
Salix cheilophila Schneid. is a naturally occurring Salix species in Mu Us Sandy Land, Inner Mongolia, China. We focused on the morphological adaptability of S. cheilophila to sand dune burial. For morphological measurements, 32 S. cheilophila seedlings were removed from a community which was in the process of being buried by a shifting sand dune. Each seedling collected included the entire root system. We measured the number, length, and biomass of the adventitious roots, primary lateral roots, and taproot, and compared the morphological characteristics of the root system, including adventitious roots, for seedlings buried to various levels in the sand. The growth range of adventitious roots increased as the length of the buried portion of the main shoot increased. In addition, the total dry weight of all current-year shoots tended to increase gradually with increasing total dry weight of the adventitious roots. These results suggest that S. cheilophila tends to make use of the sedimentary sand layer that accompanies shifting sand dunes. However, there was no correlation between biomass or number of adventitious roots and the length of the buried part of the main shoot. Thus, S. cheilophila does not grow adventitious roots proportional to the buried part. These morphological characteristics of the root system, including the adventitious roots, may indicate that S. cheilophila has poor morphological adaptability to sand dune burial.  相似文献   
44.
International Journal of Peptide Research and Therapeutics - It is demonstrated that gonadotropin-releasing hormone (GnRH) analogs can directly inhibit the proliferation of reproductive tissue...  相似文献   
45.
棉花枯萎病菌多聚半乳糖醛酸内切酶在pH大于7时不稳定,故对它进行多种化学修饰而又不影响其活性,必须在pHd小于7的体系中进行。本文报道将PGAUase在还原剂存在下,与稀酸处理的Sepharose 4B交联,获得较高活力的固定化酶。固定化酶催化动力学表明,最适pH为4,4,最适温度为55℃,在pH1至8.0范围内稳定。和溶液酶比较,对热稳定性提高,但对碱稳定性下降。以多聚半乳糖醛酸为底物,Km为0.27mmol/L,Vmax为66.67nmol/L·min,均大于溶液酶(Km=0.07mmol/L,Vmax=28.00nmol/L·min)。在pH4.8,30℃,聚半乳糖醛酸在固相酶的柱中循环水解不同的时间降解产物经圆盘电泳和等电聚焦测定,得到不同大小的寡糖片段混合物,证明固相酶和溶液酶的作用方式相同,同时使以酶解法制备一定大小的有生物活性的寡糖分子成为可能。  相似文献   
46.
To investigate the effect of apolipoprotein E (apoE) on cytokine expression profile of the liver of young mice, quantitative RT-PCR (qRT-PCR) assay and cytokine antibody array for multiplex analysis of 62 cytokines have been used to analyze characteristics of expression of cytokines in the liver of 6-week-old apoE-null (apoE−/−) mice. The levels of plasma cytokines were also analyzed. The mRNA level of IL-1β, IL-2, IL-6, ICAM-1, VCAM-1, MCP-1, NF-κB (p65), IFN-γ and IκB-α were increased significantly in apoE−/− mice comparative to wild-type (WT) mice. IL-4, IL-10 and GM-CSF, however, were slightly decreased. Compared with WT, levels of 21 cytokines altered twofold or more in apoE−/− mice, including 10 cytokines increased and 11 decreased. Expression patterns of IL-1β, IL-2, IL-4, IL-6, IL-10, GM-CSF, IFN-γ and VCAM-1 showed identical trend between cytokine antibody array and qRT-PCR analysis. Moreover, levels of IL-1β, IFN-γ and IL-6 in the plasma were elevated, while IL-4 was lightly decreased in apoE−/− mice compared to those in WT mice. These results implied that promotion of type I immune response in the liver of young apoE−/− mice due to alteration of these cytokines, and the phenotypes may be caused by the regulation of NF-κB. The inflammation and lipid metabolism dysfunction in the liver cooperated in dysfunction of the liver in young apoE−/− mice.  相似文献   
47.
Admixture mapping (AM) is a promising method for the identification of genetic risk factors for complex traits and diseases showing prevalence differences among populations. Efficient application of this method requires the use of a genomewide panel of ancestry-informative markers (AIMs) to infer the population of origin of chromosomal regions in admixed individuals. Genomewide AM panels with markers showing high frequency differences between West African and European populations are already available for disease-gene discovery in African Americans. However, no such a map is yet available for Hispanic/Latino populations, which are the result of two-way admixture between Native American and European populations or of three-way admixture of Native American, European, and West African populations. Here, we report a genomewide AM panel with 2,120 AIMs showing high frequency differences between Native American and European populations. The average intermarker genetic distance is ~1.7 cM. The panel was identified by genotyping, with the Affymetrix GeneChip Human Mapping 500K array, a population sample with European ancestry, a Mesoamerican sample comprising Maya and Nahua from Mexico, and a South American sample comprising Aymara/Quechua from Bolivia and Quechua from Peru. The main criteria for marker selection were both high information content for Native American/European ancestry (measured as the standardized variance of the allele frequencies, also known as "f value") and small frequency differences between the Mesoamerican and South American samples. This genomewide AM panel will make it possible to apply AM approaches in many admixed populations throughout the Americas.  相似文献   
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蹄蝠科的核型进化:比较染色体涂色、G带和C带分析(英文)   总被引:1,自引:0,他引:1  
Mao XG  Wang JH  Su WT  Wang YX  Yang FT  Nie WH 《动物学研究》2010,31(5):453-460
与其姐妹科(菊头蝠科)相比,蹄蝠科的细胞遗传学研究较少。迄今为止,仅少数蹄蝠科几个物种有高分辨率的G带核型报道,且有关该科核型进化的大多数结论都是基于常规Giemsa染色研究而得。该研究利用三叶小蹄蝠的染色体特异探针,通过比较染色体涂色、G和C显带,建立了5种蹄蝠的染色体同源性图谱,并探讨了它们同源染色体间的G和C带异同。结果表明:罗伯逊易位、臂内倒位以及异染色质的扩增可能是蹄蝠科物种核型进化的主要机制。通过对这5种蹄蝠物种及其外群物种之间的同源染色体片段的比较分析,作者推测蹄蝠科的祖先核型并不像先前认为的全由端着丝粒染色体组成,而应该含有中着丝粒染色体。  相似文献   
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