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The microstructure and phase composition of Al-5Ti-1B, Al-4Ti-1C and Al-5Ti-0.8B-0.2C master alloys were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS), and the effects of the three kinds of master alloys on the grain size and mechanical properties of 7050 alloy were investigated. The results show that the existence of Zr reduces the grain refining effects of Al-5Ti-1B and Al-4Ti-1C master alloys, but hardly influences the refinement of Al-5Ti-0.8B-0.2C master alloy. The reason is that Al-5Ti-0.8B-0.2C containing B-doped TiC can resist Zr-poisoning, and after adding 0.2% (mass fraction) Al-5Ti-0.8B-0.2C, the average grain size of 7050 alloy is reduced from about 200μm to (60±5)μm, the ultimate tensile strength increases from 405MPa to 515MPa, increasing by 27.2%, and the elongation rate increases from 2.1% to 4.1%. However, after adding 0.2% Al-5Ti-1B and Al-4Ti-1C master alloys, the grain size is larger and the distribution is uneven, exhibiting obvious “refinement poisoning” phenomenon.

The association between the interleukin-6 (IL-6) gene -572 C/G (rs1800796) polymorphism and type 2 diabetes mellitus (T2DM) risk remains controversial. Thus, we performed this meta-analysis by searching PubMed, Embase, Web of Science, CBMdisc and CNKI databases until January 30, 2012. In addition, hand searching of the references of identified articles was performed. A total of 10 case-control studies including 11,681 subjects were selected to evaluate the possible association. Our results showed evidence for significant association between the IL-6 gene -572 C/G polymorphism and T2DM risk (for G allele vs. C allele: odds ratio [OR] = 1.29, 95% confidence interval [CI] = 1.09-1.52, P = 0.002, P = 0.008 after Bonferroni testing; for G/G vs. C/C: OR = 1.89, 95% CI = 1.51-2.37, P < 0.00001, P < 0.00004 after Bonferroni testing; for GG vs. G/C + C/C: OR = 1.75, 95% CI = 1.20-2.56, P = 0.004, P = 0.016 after Bonferroni testing; for G/G + G/C vs. C/C: OR = 1.32, 95% CI = 1.11-1.57, P = 0.001, P = 0.004 after Bonferroni testing). In addition, similar results were obtained in the subgroup analysis based on ethnicity. In summary, the present meta-analysis suggests a significant association between the IL-6 gene -572 G allele and increased risk of T2DM., (© 2013 Blackwell Publishing Ltd/University College London.)

Epidemiological studies have evaluated the association between interleukin-6 (IL-6) gene -174 G/C polymorphism and type 1 diabetes mellitus (T1DM) risk, but results of different studies have been inconsistent. The present meta-analysis was therefore designed to clarify these controversies. PubMed, Embase and Web of Science were searched from the first available year to March 25, 2012, as well as hand searching of the references of identified articles were performed. All studies investigating the association between IL-6 gene -174 G/C polymorphism and T1DM risk were included. Data analyses were carried out by Review Manager 5.1.2 and Stata 11.0. Seven studies were included in the final meta-analysis, covering a total of 9697 T1DM cases and 8455 controls. The results showed no evidence for significant association between IL-6 gene -174 G/C polymorphism and T1DM risk (for C/C+C/G vs. G/G: OR=1.30, 95% CI=0.84-2.00, p=0.24; for C/C vs. C/G+G/G: OR=1.10, 95% CI=0.75-1.60, p=0.63; for C/C vs. G/G: OR=1.34, 95% CI=0.75-2.42, p=0.33; for C allele vs. G allele: OR=1.16, 95% CI=0.88-1.53, p=0.30). In addition, the similar results were obtained in the subgroup analysis based on ethnicity. In summary, the present meta-analysis suggests that IL-6 gene -174 G/C polymorphism is not associated with T1DM risk. However, due to the small sample size in most of the included studies and the selection bias existed in some studies, the results should be interpreted with caution., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Epidemiological studies have evaluated the association between IL-1β -511 C/T polymorphism and duodenal ulcer (DU) risk. However, the results remain conflicting. The aim of this study was to perform a meta-analysis to investigate a more authentic association between IL-1β -511 C/T polymorphism and DU. Systematic searches of electronic databases Embase, PubMed and Web of Science as well as hand searching of the references of identified articles and the meeting abstracts were performed. Study selection, data abstraction and study quality evaluation were independently conducted in duplicate. Statistical analyses were performed using software Stata 11.0. The pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were performed. Publication bias was tested by Begg's funnel plot and Egger's regression test. A total of 14 studies including 1887 cases and 2780 controls were included in our final meta-analysis. There was no evidence of significant association between IL-1β -511 C/T polymorphism and DU (for T allele vs. C allele: OR=0.93, 95% CI=0.82-1.06; for T/T vs. C/C: OR=0.83, 95% CI=0.64-1.08; for dominant model: OR=0.93, 95% CI=0.80-1.07; and for recessive model: OR=0.87, 95% CI=0.69-1.11). Significant association was found in all genetic models for the PB subgroup and sensitivity analyses. In conclusion, our meta-analysis suggests that there was no evidence of a significant association between IL-1β -511 C/T polymorphism and DU with or without Helicobacter pylori infection, whereas a significant association was found by sensitivity analyses which showed a protective effect of the T allele against DU risk., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Interleukin-6 (IL-6) gene -174 G/C polymorphism has been reported to be associated with coronary heart disease (CHD), but the results remain inconclusive. The present meta-analysis was therefore designed to clarify these controversies. This meta-analysis was performed by searching PubMed, Embase and Web of Science databases. A total of 20 studies including 9619 CHD cases and 10,919 controls were combined showing no evidence of association between IL-6 gene -174 G/C polymorphism and CHD risk (for C/C+C/G vs. G/G: OR=1.10, 95% CI=0.99-1.22, p=0.07; for C/C vs. C/G+G/G: OR=1.08, 95% CI=0.93-1.24, p=0.33; for C/C vs. G/G: OR=1.16, 95% CI=0.97-1.39, p=0.11; for C allele vs. G allele: OR=1.10, 95% CI=1.00-1.21, p=0.06). Moreover, we also did not find significant association between IL-6 gene -174 G/C polymorphism and myocardial infarction (MI) risk. However, in the subgroup analysis by ethnicity, significant association was found among Asians (for C/C+C/G vs. G/G: OR=1.35, 95% CI=1.05-1.63, p=0.02). In summary, the present meta-analysis suggests that IL-6 gene -174 G/C polymorphism is associated with increased CHD risk among Asians. However, due to the small subjects included in the subgroup analysis of Asians, the results should be interpreted with caution., (Copyright © 2012 Elsevier B.V. All rights reserved.)