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501.
Here, we established a system for displaying heterologous protein to the C terminus of the peptidoglycan-binding domain (cA domain) of AcmA (a major autolysin from Lactococcus lactis). Western blot and flow cytometric analyses revealed that the fusion proteins (cA-AmyA) of the cA domain and α-amylase from Streptococcus bovis 148 (AmyA) are efficiently expressed and successfully displayed on the surfaces of L. lactis cells. AmyA was also displayed on the cell surface while retaining its activity. Moreover, with an increase in the number of cA domains, the quantity of cA-AmyA fusion proteins displayed on the cell surface increased. When three repeats of the cA domain were used as an anchor protein, 82% of α-amylase activity was detected on the cells. The raw starch-degrading activity of AmyA was significantly higher when AmyA was fused to the C terminus of the cA domain than when it was fused to the N terminus. In addition, cA-AmyA fusion proteins were successfully displayed on the cell surfaces of Lactobacillus plantarum and Lactobacillus casei.  相似文献   
502.
Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme degradation, is a cytoprotective enzyme upregulated in the vasculature by increased flow and inflammatory stimuli. Human genetic data suggest that a diminished HO-1 expression may predispose one to abdominal aortic aneurysm (AAA) development. In addition, heme is known to strongly induce HO-1 expression. Utilizing the porcine pancreatic elastase (PPE) model of AAA induction in HO-1 heterozygous (HO-1+/-, HO-1 Het) mice, we found that a deficiency in HO-1 leads to augmented AAA development. Peritoneal macrophages from HO-1+/- mice showed increased gene expression of pro-inflammatory cytokines, including MCP-1, TNF-alpha, IL-1-beta, and IL-6, but decreased expression of anti-inflammatory cytokines IL-10 and TGF-beta. Furthermore, treatment with heme returned AAA progression in HO-1 Het mice to a wild-type profile. Using a second murine AAA model (Ang II-ApoE-/-), we showed that low doses of the HMG-CoA reductase inhibitor rosuvastatin can induce HO-1 expression in aortic tissue and suppress AAA progression in the absence of lipid lowering. Our results support those studies that suggest that pleiotropic statin effects might be beneficial in AAA, possibly through the upregulation of HO-1. Specific targeted therapies designed to induce HO-1 could become an adjunctive therapeutic strategy for the prevention of AAA disease.  相似文献   
503.
Activation of numerous pathways has been documented in non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) has emerged as a common therapeutic target. The mitogen-activated protein kinase (MAPK) and AKT signaling pathways are downstream of EGFR and deregulated via genetic and epigenetic mechanisms in many human cancers. We evaluated selected markers in the EGFR pathway with reference to outcome. Tissues from 220 cases of NSCLC patients presented in a tissue microarray were assayed with immunohistochemistry for phosphorylated AKT, phosphorylated MAPK, phosphorylated mTOR, and EGFR and then quantified by automated image analysis. Individually, the biomarkers did not predict. Combined as ratios, p-mTOR/p-AKT, and p-MAPK/EGFR function as prognostic markers of survival (p=0.008 and p=0.029, respectively), however, no significance was found after adjustment (p=0.221, p=0.103). The sum of these ratios demonstrates a stronger correlation with survival (p<0.001) and remained statistically significant after adjustment (p=0.026). The algebraic combination of biomarkers offer the capacity to understand factors that predict outcome better than current approaches of evaluating biomarkers individually or in pairs. Our results show the sum of p-mTOR/p-AKT and p-MAPK/EGFR is a potential predictive marker of survival in NSCLC patients.  相似文献   
504.
Summary We have examined the c-Ha-ras locus in 145 cancer patients of a mixed group and 164 normal individuals in Japan for restriction fragment length polymorphisms and compared the allele distributions in normal and cancer populations. The c-Ha-ras gene is highly polymorphic in Japanese as previously reported in Caucasians. Two rare alleles were found to be present with increased frequencies in Japanese cancer patients. These results suggest that genotype analysis of the c-Ha-ras gene could be used to detect cancer-prone individuals.  相似文献   
505.
This study examines the self-assembly of colloidal particles with spherical dendritic brushes. The effective interaction between these particles was studied in Monte Carlo simulations of the Kremer–Grest model. Results confirmed the transferability of the effective potential at different temperatures. Using the potential of mean force obtained from Monte Carlo simulations, the structural formation of the system was studied in a three-dimensional system. The system is a crystalline state in the intermediate density range and exhibits re-entrant melting at much higher densities. Based on generalised local bond order analysis, a refined numerical method is proposed for analysing the structural formation of colloidal particles in three-dimensional systems. The numerical technique accurately reproduced the formation of the colloidal system.  相似文献   
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