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991.
992.
Nucleotide oligomerization domain protein-1 (NOD1), a cytosolic pattern recognition receptor for the γ-D-glutamyl-meso-diaminopimelic acid (iE-DAP) is associated with the inflammatory diseases. Very little is known how bovine hepatocytes respond to specific ligands of NOD1 and sodium butyrate (SB). Therefore, the aim of our study was to investigate the role of bovine hepatocytes in NOD1-mediated inflammation during iE-DAP or LPS treatment or SB pretreatment. To achieve this aim, hepatocytes separated from cows at ∼160 days in milk (DIM) were divided into six groups: The nontreated control group (CON), the iE-DAP-treated group (DAP), the lipopolysaccharide-treated group (LPS), iE-DAP with SB group (DSB), LPS with SB group (LSB), and the SB group. Both iE-DAP and LPS highly increased the expression of both NOD1 and RIPK2, the two key factors for the immune response in hepatocytes. IκBα, NF-κB/p65, and MAP kinases (ERK, JNK, and p38) were activated through phosphorylation. The activation of NF-κB and MAPK pathway consequently increased the proinflammatory cytokines, IL-6, TNF-α, IL-8, and IFN-γ and the chemokines CCL5, CCL20, and CXCL-10. Both treatments improved iNOS/NOS2 expression. However, iE-DAP was failed to express acute phase protein SAA3, but HP and LPS HP but SAA3. These ligands also increased LRRK2, TAK1, TAB1, and β-defensins expression. The SB pretreatment at lower dose restored the function of hepatocytes by suppressing these increased molecules, as HDAC3 was inhibited. The activated NOD1 negatively regulated the expression of FOXA2. Altogether these data suggest an important role of bovine hepatocytes to promote immune responses via NOD1 expression during infection in the liver and a key role of SB to attenuate inflammation.  相似文献   
993.
Non-small-cell lung cancer (NSCLC) is one of the main causes of death induced by cancer globally. However, the molecular aberrations in NSCLC patients remain unclearly. In the present study, four messenger RNA microarray datasets (GSE18842, GSE40275, GSE43458, and GSE102287) were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between NSCLC tissues and adjacent lung tissues were obtained from GEO2R and the overlapping DEGs were identified. Moreover, functional and pathway enrichment were performed by Funrich, while the protein–protein interaction (PPI) network construction were obtained from STRING and hub genes were visualized and identified by Cytoscape software. Furthermore, validation, overall survival (OS) and tumor staging analysis of selected hub genes were performed by GEPIA. A total of 367 DEGs (95 upregulated and 272 downregulated) were obtained through gene integration analysis. The PPI network consisted of 94 nodes and 1036 edges in the upregulated DEGs and 272 nodes and 464 edges in the downregulated DEGs, respectively. The PPI network identified 46 upregulated and 27 downregulated hub genes among the DEGs, and six (such as CENPE, NCAPH, MYH11, LRRK2, HSD17B6, and A2M) of that have not been identified to be associated with NSCLC so far. Moreover, the expression differences of the mentioned hub genes were consistent with that in lung adenocarcinoma and lung squamous cell carcinoma in the TCGA database. Further analysis showed that all the six hub genes were associated with tumor staging except MYH11, while only the upregulated DEG CENPE was associated with the worse OS of patients with NSCLC. In conclusion, the current study showed that CENPE, NCAPH, MYH11, LRRK2, HSD17B6, and A2M might be the key genes contributed to tumorigenesis or tumor progression in NSCLC, further functional study is needed to explore the involved mechanisms.  相似文献   
994.
CASP13 has investigated the impact of sparse NMR data on the accuracy of protein structure prediction. NOESY and 15N-1H residual dipolar coupling data, typical of that obtained for 15N,13C-enriched, perdeuterated proteins up to about 40 kDa, were simulated for 11 CASP13 targets ranging in size from 80 to 326 residues. For several targets, two prediction groups generated models that are more accurate than those produced using baseline methods. Real NMR data collected for a de novo designed protein were also provided to predictors, including one data set in which only backbone resonance assignments were available. Some NMR-assisted prediction groups also did very well with these data. CASP13 also assessed whether incorporation of sparse NMR data improves the accuracy of protein structure prediction relative to nonassisted regular methods. In most cases, incorporation of sparse, noisy NMR data results in models with higher accuracy. The best NMR-assisted models were also compared with the best regular predictions of any CASP13 group for the same target. For six of 13 targets, the most accurate model provided by any NMR-assisted prediction group was more accurate than the most accurate model provided by any regular prediction group; however, for the remaining seven targets, one or more regular prediction method provided a more accurate model than even the best NMR-assisted model. These results suggest a novel approach for protein structure determination, in which advanced prediction methods are first used to generate structural models, and sparse NMR data is then used to validate and/or refine these models.  相似文献   
995.
目的探讨超声引导下前列腺穿刺联合外周血循环肿瘤细胞(CTCs)检测对前列腺癌预后的预测效果。方法选取2011年1月至2017年12月期间于郑州大学第二附属医院收治的83例前列腺癌患者为研究对象,全部患者均根据超声引导下经直肠前列腺穿刺活检术确诊为前列腺癌,检测病理标本中CK34BE12、p63、α-甲酰基辅酶A消旋酶(AMACR)等免疫标志物的表达状况,并采用Cell Search细胞搜索系统检测外周血CTCs的数量,据此分为阳性组(≥5个/7.5 ml)和阴性组(<5个/7.5 ml)。分析穿刺组织中免疫标志物表达状况、外周血CTCs计数与患者临床病理特征、生存状况的相关性。各标志物的阳性例数、Gleason评分>7分的比例、TNM分期等定性资料的比较采用x^2检验或Fisher确切概率法,年龄、血常规、凝血功能、肝功能、PSA水平等定量资料的比较采用t检验。采用Kaplan-Meier法进行生存分析,采用多因素Cox比例风险回归模型分析患者预后的预测因素。结果(1)全部患者中外周血CTCs、穿刺组织中CK34BE12、p63、AMACR的阳性率分别为31.33、3.61、3.61、86.75。CTCs阳性组的AMACR阳性率为100.00,高于CTCs阴性组的80.70,差异有统计学意义(x^2=4.227,P<0.05)。(2)AMACR阳性组患者的血红蛋白(HB)低于AMACR阴性组[(123.66±13.33)g/L比(134.89±20.08)g/L,t=2.420,P=0.018],血小板(PLT)、血清谷丙转氨酶、D-二聚体(DD)、前列腺特异抗原(PSA)水平、Gleason评分>7分的比例均高于AMACR阴性组[(197.23±36.98)×10^9/L比(172.83±33.33)×10^9/L,t=2.062,P=0.042;(38.80±10.03)U/L比(31.46±7.83)U/L,t=2.317,P=0.023;(255.00±38.80)μg/L比(220.81±30.99)μg/L,t=2.785,P=0.007;(26.60±12.23)ng/ml比(17.90±8.88)ng/ml,t=2.263,P=0.026;45.83比9.09,x^2=3.916,P=0.048],差异有统计学意义(P<0.05)。CTCs阳性组患者的HB低于CTCs阴性组[(121.69±15.89)g/L比(132.73±18.85)g/L,t=2.767,P=0.007],血清碱性磷酸酶、DD、PSA水平、Gleason评分>7分、T3~T4期、M1期的比例均高于CTCs阴性组[(105.69±30.56)U/L比(88.89±35.58)U/L,t=2.205,P=0.030;(256.63±35.86)μg/L比(236.98±33.30)μg/L,t=2.368,P=0.020;(30.09±11.89)ng/ml比(23.33±10.99)ng/ml,t=2.533,P=0.013;57.69比33.33,x^2=4.381,P=0.036;30.77比8.77,x^2=4.981,P=0.026;50.00比17.54,x^2=9.390,P=0.002],差异有统计学意义(P<0.05)。(3)全部患者的中位生存时间为58.33个月,1、3、5年的生存率分别为88.95、51.81、30.12。AMACR阳性组、CTCs阳性组患者的中位生存时间为40.93、36.93个月,低于AMACR阴性组、CTCs阴性组的66.66、69.56个月,差异有统计学意义(P<0.05)。多因素Cox比例风险回归模型分析结果表明,Gleason评分>7分、M1期、AMACR阳性、CTCs阳性是患者死亡的独立危险因素(HR=1.883、3.666、2.009、2.923,P<0.05)。结论超声引导下前列腺穿刺联合外周血CTCs检测对前列腺癌患者的预后具有重要的预测价值,临床上可根据穿刺组织中AMACR表达水平和外周血CTCs计数进行预后的综合分析。  相似文献   
996.
Zhou  Hai-Yan  Li  Yi-Zuo  Jiang  Rui  Hu  Hai-Feng  Wang  Yuan-Shan  Liu  Zhi-Qiang  Xue  Ya-Ping  Zheng  Yu-Guo 《Bioprocess and biosystems engineering》2019,42(10):1573-1582
Bioprocess and Biosystems Engineering - R-2-(4-hydroxyphenoxy)propionic acid (R-HPPA) is a key intermediate of the enantiomerically pure phenoxypropionic acid herbicides. R-HPPA could be...  相似文献   
997.
998.
3,3′,4,4′,5-Polychlorinated biphenyl (PCB126) is a persistent organic environmental pollutant which can affect various biological activities of organisms, such as immunity, neurological function, and reproduction. In our study, we aimed to investigate the effects of PCB126 on granulosa cells (GCs). GCs were collected from ovaries in PMSG-treated mice, after 24 hours culture. GCs were then incubated with 10 pg/mL, 100 pg/mL, and 10 ng/mL of PCB126 for another 24 hours. Following these steps, exposed GCs were collected for further experimentation. Our data showed that the number of GCs in the 10 ng/mL PCB126 decreased. Meanwhile, pyknotic nuclei and condensed chromatin increased, while the apoptotic cells in the 10 ng/mL PCB126 group were significantly increased. Furthermore, the expression of the apoptotic executive protein caspase-3 increased after PCB126 treatment. The expression of Bax, Bcl-2, and Bim related to the mitochondrial apoptosis pathway were also influenced to different degrees. Thus, our data suggested that PCB126 affect the GCs apoptosis, and mitochondrial apoptosis pathway was involved in this process.  相似文献   
999.
Cervical cancer is the fourth most lethal human malignancy and the leading cause of death among females around the world. Many antitumor agents have microbial origins. 5′-epi-SPA-6952A is a new 24-membered macrolide isolated from the cultured broth of Streptomyces diastatochromogenes. Therefore, we studied the activity and molecular mechanism of 5′-epi-SPA-6952A in human cervical carcinoma HeLa cell. The results showed that 5′-epi-SPA-6952A significantly inhibited cell proliferation and migration. In addition, 5′-epi-SPA-6952A obviously increased the production of intracellular reactive oxygen species and DNA damage in HeLa cells. Moreover, nuclear shrinkage of cells, decrease in mitochondrial membrane potential, and upregulation of Bax/Bcl-2 ratio resulted in the release of cytochrome c, and activation of caspase-9/3 was observed in HeLa cells treated with 5′-epi-SPA-6952A, which means it enhanced the intrinsic mitochondrial apoptosis. Besides, DNA-damage associated proteins poly (ADP-ribose) polymerase (PARP) and p53 were also studied, and the expressions of cleaved-PARP and p53 were drastically increased in HeLa cells treated with 5′-epi-SPA-6952A. Furthermore, we confirmed that 5′-epi-SPA-6952A affected the survival of HeLa cells by blocking cell cycle progression in the G1 phase. Taken together, the results shows that 5′-epi-SPA-6952A significantly inhibited HeLa cells proliferation via intrinsic mitochondrial apoptosis, cell cycle arrest, and blocking cell migration.  相似文献   
1000.
Skeletal muscle is an important and complex organ with multiple biological functions in humans and animals. Proliferation and differentiation of myoblasts are the key steps during the development of skeletal muscle. MicroRNA (miRNA) is a class of 21-nucleotide noncoding RNAs regulating gene expression by combining with the 3′-untranslated region of target messenger RNA. Many studies in recent years have suggested that miRNAs play a critical role in myogenesis. Through high-throughput sequencing, we found that miR-323-3p showed significant changes in the longissimus dorsi muscle of Rongchang pigs in different age groups. In this study, we discovered that overexpression of miR-323-3p repressed myoblast proliferation and promoted differentiation, whereas the inhibitor of miR-323-3p displayed the opposite results. Furthermore, we predicted Smad2 as the target gene of miR-323-3p and found that miR-323-3p directly modulated the expression level of Smad2. Then luciferase reporter assays verified that Smad2 was a target gene of miR-323-3p during the differentiation of myoblasts. These findings reveal that miR-323-3p is a positive regulator of myogenesis by targeting Smad2. This provides a novel mechanism of miRNAs in myogenesis.  相似文献   
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