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71.
Influence of Genetic Variation in the C-Reactive Protein Gene on the Inflammatory Response During and After Acute Coronary Ischemia 总被引:4,自引:0,他引:4
J. Suk Danik D. I. Chasman C. P. Cannon D. T. Miller R. Y. L. Zee P. Kozlowski D. J. Kwiatkowski P. M. Ridker 《Annals of human genetics》2006,70(6):705-716
The aim of this research was to assess whether common genetic variants within the C-reactive protein gene ( CRP ) are related to the degree of acute rise in plasma C-reactive protein (CRP) levels following an acute coronary syndrome (ACS). While polymorphisms within CRP are associated with basal CRP levels in healthy men and women, less is known about the relationship of such genetic variants and the degree of CRP rise during and after acute ischemia. Plasma CRP is associated with increased rates of recurrent coronary events. We evaluated seven common genetic variants within CRP and assessed their relationship to the degree of rise in CRP levels immediately following an acute coronary syndrome in 1827 European American patients. Variants in the putative promoter region, −757T > C and −286C > T > A, were associated with the highest CRP elevations after ACS. Patients with two copies of the A allele of SNP −286C > T > A had median CRP values of 76.6 mg/L, compared to 11.1 mg/L in patients with no copies of the rare variant (p-value <0.0001), post ACS. The lowest CRP values were found for patients with minor alleles of the exonic 1059G > C and the 3'untranslated region 1846G > A SNPs. For example, patients homozygous for the minor allele of 1059G > C had 71% lower median CRP values than those homozygous for the major allele [3.5 vs 12.0 mg/L, p < 0.0001]. These trends persisted in the chronic stable phase after ischemia had resolved, and after adjustment for infarct size by peak creatinine kinase levels and clinical status by Killip class. Assessment of CRP genetic variants identified patients with higher and lower CRP elevation after acute coronary syndrome. 相似文献
72.
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74.
P F Maness 《Journal of neuroscience research》1986,16(1):127-139
The advent of recombinant DNA technology has led to the identification in the DNA of normal animal cells of over 30 proto-oncogenes that are homologous to retroviral transforming genes. One of these encodes a protein kinase (pp60c-src) of unknown function, that is preferentially synthesized in brain and neural retina. Here the expression of pp60c-src in the peripheral nervous system was examined in sensory neurons from chick dorsal root ganglia with antisera raised against the transforming protein of Rous sarcoma virus (pp60v-src) expressed in Escherichia coli carrying the cloned v-src gene. This antiserum recognizes pp60c-src specifically in normal chicken cells. Western immunoblotting showed that dorsal root ganglia of stage 30 (day 6.5) chick embryos contained elevated levels of pp60c-src. Immunoperoxidase staining of neuron-enriched cultures prepared from chick dorsal root ganglia showed pp60c-src immunoreactivity in cells with neuronal morphology; flat, fibroblastic cells contained no detectable immunoreactivity. Indirect double immunofluorescence with pp60src antibodies and monoclonal antibodies against the 200-kD subunit of neurofilament protein confirmed that the cells expressing pp60c-src were neurons. Ninety-six percent of the neurofilament-positive cells were immunoreactive with pp60src antibodies, and conversely, all pp60c-src-positive cells were immunoreactive with neurofilament antibodies. pp60c-src immunofluorescence appeared to be distributed over the cell body, processes, and growth cones. These results clearly demonstrate that pp60c-src is a product of neurons and is expressed in sensory neurons in culture. 相似文献
75.
ALVARO MARTÍNEZ DEL POZO MARIA GASSET MERCEDES O
ADERRA JOS G. GAVILANES 《Chemical biology & drug design》1989,34(5):416-422
α-Sarcin binds one Zn(II) cation per protein molecule, with a Kd value of 0.9 mM, determined by equilibrium dialysis experiments. Ca(II), Mg(II), and Mn(II) do not bind to α-sarcin. Cd(II) and Co(II) also behave as Zn(II). The binding produces local modifications on the protein conformation affecting the microenvironment of tryptophan residues. The three cations modify the fluorescence emission of the protein. The near-u. v. circular dichroism spectrum of the protein is also altered. The binding of Zn(II) and related cations does not modify the secondary structure of the protein. The ribonucleolytic activity of a-sarcin is inhibited upon Zn(II) binding, but no alteration of the ability of the protein to aggregate phospholipid vesicles has been observed. 相似文献
76.
Francisco Jose Martinez-Guijarro Eduardo Soriano Jose Antonio del Rio Carlos Lopez-Garcia 《Brain research》1991,547(2)
An antibody against the calcium binding protein parvalbumin selectively labels a set of neurons in the cerebral cortex of lizards. Golgi-like immunostained bipolar, multipolar and pyramid-like neurons appear mainly located in the inner plexiform layers. Parvalbumin-immunoreactive (PARV-IR) puncta are concentrated in the cell layer of the dorsal and dorsomedial cortices showing a basket-like distribution. The morphology and distribution of PARV-IR neurons and puncta overlap GABA-immunostaining in the cerebral cortex of lizards. Thus, it is likely that PARV-IR neurons are a subset of the cortical GABAergic neurons of lizards. 相似文献
77.
78.
Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy. 相似文献
79.
目的探讨内源性热休克蛋白90(HSP90)在缺氧心肌细胞丝氨酸苏氨酸蛋白激酶(AKT)相关信号通路中的作用。方法建立新生Wistar大鼠心肌细胞缺氧模型,将细胞分为正常组、缺氧组、加入HSP90特异性阻断剂格尔德霉素后再缺氧组(格尔德霉素+缺氧组)。于缺氧后1、3、6、12、24、48h用噻唑蓝法检测心肌细胞的活力;缺氧24h,原位缺口末端标记法检测心肌细胞凋亡指数(AI);缺氧1、3、6、12、24h,蛋白质印迹法检测大鼠心肌细胞中内源性HSP90及AKT表达水平。结果(1)缺氧24、48h,缺氧组、格尔德霉素+缺氧组细胞活力均较正常组明显下降(P〈0.05);格尔德霉素+缺氧组细胞活力缺氧12h即开始明显下降,缺氧48h时明显低于缺氧组(P〈0.05)。(2)缺氧24h,缺氧组细胞AI为(10.7±1.2)%,明显高于正常组[(1.9±0.3)%.P〈0.05];格尔德霉素+缺氧组细胞AI为(26、3±5.3)%,明显高于缺氧组(P〈0.01)。(3)缺氧12h,缺氧组心肌细胞内源性HSP90及AKT表达水平高于正常组与格尔德霉素+缺氧组;缺氧24h,缺氧组有所下降.格尔德霉素+缺氧组则下降更明显。结论内源性HSP90对维持心肌细胞的活力有重要作用.缺氧心肌细胞AKT表达水平可受内源性HSP90表达水平的影响。 相似文献
80.
目的:探讨胰岛素样生长因子 I(IGF-Ⅰ)和胰岛素样生长因子结合蛋白 1(IGFBP—1)与妊高征(PIH)的关系。方法:采用免疫放射法测定50例妊高征孕妇(PIH组)和108例正常孕妇(对照组)的血清 IGF-Ⅰ、IGFBP-1水平,并对其结果进行相关性分析。结果:①妊高征孕妇血清 IGF-Ⅰ水平低于正常孕妇(P<0.05),且重度妊高征孕妇血清 IGF-Ⅰ水平低于中度和轻度孕妇(P<0.05,P<0.01)。②妊高征孕妇血清 IGFBP-1水平高于正常孕妇(P<0.05),且重度妊高征孕妇血清 IGFBP-1水平高于中度和轻度孕妇(P<0.05,P<0.01)。③两组孕妇血清 IGF-Ⅰ水平与血清 IGFBP-1水平呈负相关(r=-0.386,P<0.05)。④妊高征孕妇血清 IGF-Ⅰ水平与舒张压呈负相关(r=-0.386,P<0.05),血清 IGFBP-1水平与舒张压呈正相关(r=0.632,P<0.01)。结论:妊高征孕妇血清 IGF-Ⅰ、IGFBP-1水平的高低可反映妊高征的严重程度。 相似文献