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101.
目的:观察大黄对急性百草枯中毒大鼠TNF-α、IL-10的干预作用,探讨其可能的作用机制。方法:90只SD大鼠随机分为生理盐水对照组(A组)、PQ(60 mg/kg)灌胃染毒组(B组)、生大黄(300mg/kg.d)干预组(C组),每组30只。中毒后6h、24h、72h分批处死存活的大鼠,并且检测大鼠血浆TNF-α、IL-10水平。结果:B组、C组TNF-α、IL-10水平在染毒后6h开始升高,72h达到高峰,与A组相比,差异有统计学意义(P〈0.05、P〈0.01),在相同时间点C组TNF-α和IL-10的表达低于B组,差异均有统计学意义(P〈0.01)。B组、C组血浆TNF-α、IL-10水平与中毒时间呈显著正性相关关系(r=0.849,P〈0.01;r=0.790,P〈0.01;r=0.0.943,P〈0.01;r=0.892,P〈0.01)。结论:大黄能够通过降低百草枯中毒大鼠体内的TNF-α、IL-10水平,减轻百草枯对大鼠的损伤作用 相似文献
102.
High major histocompatibility complex-unrestricted lysis of simian immunodeficiency virus envelope-expressing cells predisposes macaques to rapid AIDS progression
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Before the development of virus-specific immune responses, peripheral blood mononuclear cells (PBMC) from uninfected rhesus monkeys and human beings have the capacity to lyse target cells expressing simian immunodeficiency virus (SIV) or human immunodeficiency virus-1 (HIV) envelope (gp130 and gp120) antigens. Lysis by naive effector cells does not require major histocompatibility complex (MHC)-restricted antigen presentation, is equally effective for allogeneic and xenogeneic targets, and is designated MHC-unrestricted (UR) lysis. UR lysis is not sensitive to EGTA and does not require de novo RNA or protein synthesis. Several kinds of envelope-expressing targets, including cells that poorly express MHC class I antigens, can be lysed. CD4(+) effectors are responsible for most of the lytic activity. High lysis is correlated with high expression of HIV or SIV envelope, specifically, the central one-third of the gp130 molecule, and lysis is completely inhibited by a monoclonal antibody against envelope. Our work extends observations of human lymphocytes expressing HIV gp120 to the SIV/rhesus monkey model for AIDS. Additionally, we address the relevance of UR lysis in vivo. A survey of PBMC from 56 uninfected rhesus monkeys indicates that 59% of the individuals had peak UR lytic activity above 15% specific lysis. Eleven of these monkeys were subsequently infected with SIV. Animals with UR lytic activity above 15% specific lysis were predisposed to more rapid disease progression than animals with low UR lytic activity, suggesting a strong correlation between this form of innate immunity and disease progression to AIDS. 相似文献
103.
人重组白蛋白基因在巴斯德毕赤酵母中的高效表达 总被引:10,自引:0,他引:10
The yeast Pichia pastoris was transformed by the multi\|copy Pichia expression vector that can express secreted human albumin.The high level expression of cell line was selected after screening.The expression of human recombinant albumin in Pichia pastoris induced by different methods were compared.The retio of secreted human albumin is 80% in total secreted proteins and the expression level reaches as high as is 10g/L. 相似文献
104.
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106.
人源性抗HBsAg Fab抗体的发酵生产研究 总被引:3,自引:0,他引:3
为了适应工业生产的需要,利用fed—batch方法,重组人源性抗HBsAg Fab抗体酵母工程菌在30L发酵罐中进行了高密度发酵,发酵最适温度30℃,pH值范围5.0~5.3,溶氧范围20%~30%。发酵液OD600值达到300时开始诱导,甲醇最佳诱导浓度为10mL/L。重组人源性抗HBsAg Fab抗体经离子交换层析纯化,纯化产品经SDS-PAGE、Western blot进行分析和ELISA方法进行活性测定。结果显示,重组Fab抗体在Fed-batch发酵系统中可高效表达,经过192h的发酵生产,重组人源性抗HBsAg Fab抗体的表达量可达412mg/L。发酵上清经过离子交换层析纯化,获得纯度为95%的重组Fab抗体,该Fab抗体经ELISA分析具有较高的HBsAg抗原亲和力和特异性。结果证实可以通过高密度发酵毕赤酵母工程菌来高效生产重组人源性抗HBsAg Fab抗体,为后续的工业化生产应用奠定了基础。 相似文献
107.
108.
Knowledge of protein-protein interactions (PPIs) plays an important role in constructing protein interaction networks and understanding the general machineries of biological systems. In this study, a new method is proposed to predict PPIs using a comprehensive set of 930 features based only on sequence information, these features measure the interactions between residues a certain distant apart in the protein sequences from different aspects. To achieve better performance, the principal component analysis (PCA) is first employed to obtain an optimized feature subset. Then, the resulting 67-dimensional feature vectors are fed to Support Vector Machine (SVM). Experimental results on Drosophila melanogaster and Helicobater pylori datasets show that our method is very promising to predict PPIs and may at least be a useful supplement tool to existing methods. 相似文献
109.
Myokine IL-15 regulates the crosstalk of co-cultured porcine skeletal muscle satellite cells and preadipocytes 总被引:1,自引:0,他引:1
Yinghui Li Fengna Li Binbin Lin Xiangfeng Kong Yulong Tang Yulong Yin 《Molecular biology reports》2014,41(11):7543-7553
The present study was carried out to preliminarily reveal the underlying mechanisms of the co-culture system between porcine muscle satellite cells (SCs) and stromal-vascular cells (SVs). The two cell types were co-cultured to assess both proliferation and differentiation. Desmin and Pref-1 immunofluorescence staining technique were taken to identify the two types of isolated cells. The expression of specific marker genes Myogenin was up-regulated in SCs (P < 0.05) and the differentiation of SCs could be promoted when co-cultured with preadipocytes compared with the single-cultured control, while expression of c/EBPβ in SVs was down-regulated (P < 0.05) and the differentiation of preadipocytes could be inhibited. Furthermore, secretion of myokine IL-15 was markedly increased, as well as its gene and protein expression levels in co-culture supernatants. However, the secretion of adipokine leptin was significantly decreased. These findings demonstrate that myokines like IL-15 could facilitate the SCs’ differentiation while inhibit the SVs differentiation, and act as an important regulator of co-culture between muscle cells and adipocytes. 相似文献
110.
Lv K Guo Y Zhang Y Wang K Jia Y Sun S 《Biochemical and biophysical research communications》2008,374(1):101-105
The biological mechanism of a recent discovered association of type 2 diabetes with the ACAA-insertion/deletion polymorphism at the 3′UTR of the IGF2R gene has remained unclear. A very recently emerging novel polymorphic control layer by microRNAs (miRNAs) makes it possible to elucidate this issue. In this study, a prediction by web tools MicroInspector and miRanda demonstrated that DNA sequence polymorphism (DSPs) ACAA-insertion/deletion in IGF2R 3′UTR is located within the hsa-miR-657 and hsa-miR-453 binding sites. And luciferase reporter assay revealed that hsa-miR-657 acts directly at the 3′UTR of the IGF2R. Furthermore, ACAA-deletion exerted a further repression compared with ACAA-insertion, indicating that hsa-miR-657 regulates IGF2R gene expression in a polymorphic control manner. Importantly, we also demonstrated that hsa-miR-657 can translationally regulate the IGF2R expression levels in Hep G2 cells. Thus, our findings testify the possibility that the ACAA-insertion/deletion polymorphism may result in the change of IGF2R expression levels at least in part by hsa-miR-657-mediated regulation, contributing to the elucidation for the pathogenesis of type 2 diabetes and raise the possibility that miRNAs or in combination with functional DNA sequence polymorphism may be valuable in the treatment of human type 2 diabetes. 相似文献