Co30Cr8W1.6C3Ni1.4Si coatings were fabricated on Ti6Al4V alloy using a laser thermal spraying(LTS).The surface and cross-section morphologies,phases and bonding strength of obtained coatings were investigated using sc...Co30Cr8W1.6C3Ni1.4Si coatings were fabricated on Ti6Al4V alloy using a laser thermal spraying(LTS).The surface and cross-section morphologies,phases and bonding strength of obtained coatings were investigated using scanning electronic microscopy(SEM),X-ray diffraction(XRD),and scratch test,respectively.The effects of laser power on the coefficients of friction(COFs)and corrosive-wear behaviors of Co30Cr8W1.6C3Ni1.4Si coatings were investigated using a wear tester in 3.5%NaCl solution,and the electrochemical corrosion performance was analyzed using an electrochemical workstation.The experimental results show that the Co30Cr8W1.6C3Ni1.4Si coating is bonded with the substrate in the metallurgical form,and the bonding strengths of Co30Cr8W1.6C3Ni1.4Si coatings fabricated at the laser power of 1000,1200,and 1400 W are 76.5,56.5,and 55.6 N,respectively.The average COFs of Co30Cr8W1.6C3Ni1.4Si coatings fabricated at the laser power of 1000,1200,and 1400 W are 0.769,0.893,and 0.941,respectively;and the corresponding wear rates are 0.267×105,0.3178×105,and 0.325×105μm3/Nm,respectively,which increases with the increase of laser power,the wear mechanism is primarily abrasive wear.The corrosion potential of Co30Cr8W1.6C3Ni1.4Si coatings fabricated at the laser power of 1000,1200,and 1400 W is-0.05,-0.25,and-0.31 V,respectively,higher than-0.45 V of substrate which enhances the electrochemical corrosion resistance of substrate.展开更多
目的通过检测长链非编码RNA(long non-coding RNA,lncRNA)唐氏综合征关键区域8(Down syndrome critical region 8,DSCR8)在胃癌患者胃癌组织中的表达情况,对其表达水平与患者预后的关系以及与信号传导和转录激活因子3(signal transducer...目的通过检测长链非编码RNA(long non-coding RNA,lncRNA)唐氏综合征关键区域8(Down syndrome critical region 8,DSCR8)在胃癌患者胃癌组织中的表达情况,对其表达水平与患者预后的关系以及与信号传导和转录激活因子3(signal transducer and activator of transcription 3,STAT3)、微小RNA-98-5p(miR-98-5p)的相关性进行探讨。方法选取2013年8月至2015年6月185例我院已确诊收治的胃癌患者手术切除的胃癌组织、癌旁组织标本,采用实时荧光定量PCR方法检测组织样本中DSCR8、Stat3、miR-98-5p的表达情况,对DSCR8与胃癌临床病理参数的关系进行分析;DSCR8与STAT3、miR-98-5p以及STAT3和miR-98-5p间相关性用Pearson相关系数进行分析;采用Kaplan-Meier进行生存曲线分析;胃癌患者预后的影响因素使用Cox生存回归分析方法。结果与癌旁组织相比,胃癌组织中DSCR8的表达水平显著增加(P<0.05);DSCR8表达在患者淋巴结转移、肿瘤大小和TNM分期中差异有统计学意义(P<0.05)。胃癌组织中STAT3的表达水平显著增加,而miR-98-5p的表达水平则显著降低(P<0.05),二者呈显著负相关;DSCR8与STAT3呈显著正相关,而与miR-98-5p呈显著负相关;与DSCR8高表达组相比,DSCR8低表达组预后生存率较高(P<0.05)。多因素分析发现,淋巴结转移、TNM分期、肿瘤大小、DSCR8高表达均是影响预后生存的独立危险因素(P<0.05)。结论胃癌患者胃癌组织中DSCR8呈高表达,且与患者临床病理参数及预后生存情况密切相关,检测其表达水平对判断患者预后生存情况具有重要价值。展开更多
AIM: To investigate the influence of the CagA diversity in Helicobacter pylori (H. pylori ) strains from Colombia on the host cell biology. METHODS: Eighty-four H. pylori-cagA positive strains with different Glu-Pro-I...AIM: To investigate the influence of the CagA diversity in Helicobacter pylori (H. pylori ) strains from Colombia on the host cell biology. METHODS: Eighty-four H. pylori-cagA positive strains with different Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs patterns, isolated from patients with gastritis (n=17), atrophic gastritis (n=17), duodenal ulcer (n=16), intestinal metaplasia (n=16) and gastric cancer (n=18), were included. To determine the integrity of the cag pathogenicity island (cag PAI) we evaluated the presence of cagA, cagT, cagE, and cag10 genes by polymerase chain reaction. AGS gastric epithelial cellswere infected with each strain and assayed for translo-cation and tyrosine phosphorylation of CagA by western blot, secretion of interleukin-8 (IL-8) by enzyme-linked immuno sorbent assay after taking supernatants from cocultures and cell elongation induction. For cell elongation quantification, coculture photographs were taken and the proportion of "hummingbird" cells (>15 μm) was determined. RESULTS: Overall 72% (60/84) of the strains were found to harbor a functional cag PAI. Levels of phos-phorylated CagA were significantly higher for isolates from duodenal ulcer than the ones in strains from gas-tritis, atrophic gastritis, intestinal metaplasia and gastric cancer (49.1% ± 23.1% vs 21.1% ± 19.5%, P < 0.02; 49.1% ± 23.1% vs 26.2%±14.8%, P<0.045; 49.1% ± 23.1% vs 21.5% ± 19.5%, P<0.043 and 49.1% ± 23.1% vs 29.5% ± 27.1%, P < 0.047 respectively). We observed variable IL-8 expression levels ranging from 0 to 810 pg/mL and from 8.8 to 1442 pg/mL at 6 h and 30 h post-infection, respectively. cagPAI-defective strains did not induce detectable levels of IL-8 at 6 h post-infection. At 30 h post-infection all strains induced IL-8 expression in AGS cells, although cagPAI-defective strains induced significantly lower levels of IL-8 than strains with a functional cagPAI (57.1 ± 56.6 pg/mL vs 513.6 ± 338.6 pg/mL,P < 0.0001). We did not observe differences in the extent of cell elongation induction between strains with a functional or a defective cagPAI in 6 h cocultures. At 24 h post infection strains with functionalcagPAI showed high diversity in the extent of hummingbird phenotype induction ranging from 7% to 34%. cag PAI defective strains induced significantly lower levels of elongation than strains with functional cag-PAI with one or more than one EPIYA-C motif (15.1% ± 5.2%vs 18.9% ± 4.7%,P < 0.03; and 15.1% ± 5.2% vs 20.0% ± 5.1%, P < 0.003 respectively). No differences were observed in cellular elongation inductionor IL-8 expression among H. pylori strains bearing one and more than one EPIYA-C motifs, neither at 6 h nor at 24 h of coculture. There were no associations between the levels of induction of cell elongation or IL-8 expression and number of EPIYA motifs or pathology. CONCLUSION: The present work describes a lack of association between H. pylori CagA protein EPIYA motifs variations from Colombian isolates and disease-associated cellular responses.展开更多
基金Funded by the Key Research and Development Project of Jiangsu Province(BE2016052)。
文摘Co30Cr8W1.6C3Ni1.4Si coatings were fabricated on Ti6Al4V alloy using a laser thermal spraying(LTS).The surface and cross-section morphologies,phases and bonding strength of obtained coatings were investigated using scanning electronic microscopy(SEM),X-ray diffraction(XRD),and scratch test,respectively.The effects of laser power on the coefficients of friction(COFs)and corrosive-wear behaviors of Co30Cr8W1.6C3Ni1.4Si coatings were investigated using a wear tester in 3.5%NaCl solution,and the electrochemical corrosion performance was analyzed using an electrochemical workstation.The experimental results show that the Co30Cr8W1.6C3Ni1.4Si coating is bonded with the substrate in the metallurgical form,and the bonding strengths of Co30Cr8W1.6C3Ni1.4Si coatings fabricated at the laser power of 1000,1200,and 1400 W are 76.5,56.5,and 55.6 N,respectively.The average COFs of Co30Cr8W1.6C3Ni1.4Si coatings fabricated at the laser power of 1000,1200,and 1400 W are 0.769,0.893,and 0.941,respectively;and the corresponding wear rates are 0.267×105,0.3178×105,and 0.325×105μm3/Nm,respectively,which increases with the increase of laser power,the wear mechanism is primarily abrasive wear.The corrosion potential of Co30Cr8W1.6C3Ni1.4Si coatings fabricated at the laser power of 1000,1200,and 1400 W is-0.05,-0.25,and-0.31 V,respectively,higher than-0.45 V of substrate which enhances the electrochemical corrosion resistance of substrate.
文摘目的通过检测长链非编码RNA(long non-coding RNA,lncRNA)唐氏综合征关键区域8(Down syndrome critical region 8,DSCR8)在胃癌患者胃癌组织中的表达情况,对其表达水平与患者预后的关系以及与信号传导和转录激活因子3(signal transducer and activator of transcription 3,STAT3)、微小RNA-98-5p(miR-98-5p)的相关性进行探讨。方法选取2013年8月至2015年6月185例我院已确诊收治的胃癌患者手术切除的胃癌组织、癌旁组织标本,采用实时荧光定量PCR方法检测组织样本中DSCR8、Stat3、miR-98-5p的表达情况,对DSCR8与胃癌临床病理参数的关系进行分析;DSCR8与STAT3、miR-98-5p以及STAT3和miR-98-5p间相关性用Pearson相关系数进行分析;采用Kaplan-Meier进行生存曲线分析;胃癌患者预后的影响因素使用Cox生存回归分析方法。结果与癌旁组织相比,胃癌组织中DSCR8的表达水平显著增加(P<0.05);DSCR8表达在患者淋巴结转移、肿瘤大小和TNM分期中差异有统计学意义(P<0.05)。胃癌组织中STAT3的表达水平显著增加,而miR-98-5p的表达水平则显著降低(P<0.05),二者呈显著负相关;DSCR8与STAT3呈显著正相关,而与miR-98-5p呈显著负相关;与DSCR8高表达组相比,DSCR8低表达组预后生存率较高(P<0.05)。多因素分析发现,淋巴结转移、TNM分期、肿瘤大小、DSCR8高表达均是影响预后生存的独立危险因素(P<0.05)。结论胃癌患者胃癌组织中DSCR8呈高表达,且与患者临床病理参数及预后生存情况密切相关,检测其表达水平对判断患者预后生存情况具有重要价值。
基金Supported by National Cancer Institute, Bogotá, Colombia,Grant No. 41030310 to Bravo MM and Sciences Faculty, LosAndes University, Bogotá, Colombia
文摘AIM: To investigate the influence of the CagA diversity in Helicobacter pylori (H. pylori ) strains from Colombia on the host cell biology. METHODS: Eighty-four H. pylori-cagA positive strains with different Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs patterns, isolated from patients with gastritis (n=17), atrophic gastritis (n=17), duodenal ulcer (n=16), intestinal metaplasia (n=16) and gastric cancer (n=18), were included. To determine the integrity of the cag pathogenicity island (cag PAI) we evaluated the presence of cagA, cagT, cagE, and cag10 genes by polymerase chain reaction. AGS gastric epithelial cellswere infected with each strain and assayed for translo-cation and tyrosine phosphorylation of CagA by western blot, secretion of interleukin-8 (IL-8) by enzyme-linked immuno sorbent assay after taking supernatants from cocultures and cell elongation induction. For cell elongation quantification, coculture photographs were taken and the proportion of "hummingbird" cells (>15 μm) was determined. RESULTS: Overall 72% (60/84) of the strains were found to harbor a functional cag PAI. Levels of phos-phorylated CagA were significantly higher for isolates from duodenal ulcer than the ones in strains from gas-tritis, atrophic gastritis, intestinal metaplasia and gastric cancer (49.1% ± 23.1% vs 21.1% ± 19.5%, P < 0.02; 49.1% ± 23.1% vs 26.2%±14.8%, P<0.045; 49.1% ± 23.1% vs 21.5% ± 19.5%, P<0.043 and 49.1% ± 23.1% vs 29.5% ± 27.1%, P < 0.047 respectively). We observed variable IL-8 expression levels ranging from 0 to 810 pg/mL and from 8.8 to 1442 pg/mL at 6 h and 30 h post-infection, respectively. cagPAI-defective strains did not induce detectable levels of IL-8 at 6 h post-infection. At 30 h post-infection all strains induced IL-8 expression in AGS cells, although cagPAI-defective strains induced significantly lower levels of IL-8 than strains with a functional cagPAI (57.1 ± 56.6 pg/mL vs 513.6 ± 338.6 pg/mL,P < 0.0001). We did not observe differences in the extent of cell elongation induction between strains with a functional or a defective cagPAI in 6 h cocultures. At 24 h post infection strains with functionalcagPAI showed high diversity in the extent of hummingbird phenotype induction ranging from 7% to 34%. cag PAI defective strains induced significantly lower levels of elongation than strains with functional cag-PAI with one or more than one EPIYA-C motif (15.1% ± 5.2%vs 18.9% ± 4.7%,P < 0.03; and 15.1% ± 5.2% vs 20.0% ± 5.1%, P < 0.003 respectively). No differences were observed in cellular elongation inductionor IL-8 expression among H. pylori strains bearing one and more than one EPIYA-C motifs, neither at 6 h nor at 24 h of coculture. There were no associations between the levels of induction of cell elongation or IL-8 expression and number of EPIYA motifs or pathology. CONCLUSION: The present work describes a lack of association between H. pylori CagA protein EPIYA motifs variations from Colombian isolates and disease-associated cellular responses.
