Effects of sulfonylureas on lipids in type 2 diabetes mellitus: a meta-analysis of randomized controlled trials.

OBJECTIVE: Previous studies suggested that dyslipidemia was potentially associated with anti-diabetic medications of sulfonylureas (SUs). The results were, however, inconsistent. Therefore, we conducted a meta-analysis of randomized controlled trials (RCTs) to assess the effects of SUs on the level of lipids in patients with type 2 diabetes mellitus (T2DM). METHODS: We searched PubMed, EMBASE, and CENTRAL databases for RCTs that addressed the effects of second- and/or third-generation SUs used in T2DM patients on lipids profiles with study duration of at least 12 weeks. Two reviewers independently screened literature, collected data, and assessed methodological quality of included studies. The meta-analysis was performed by using the RevMan5.1 software. RESULTS: A total of 59 RCTs were included, of which 52 were included for final meta-analysis. The results suggested that SUs statistically increased the levels of FFA (SMD = 0.24, 95%CI 0.06 to 0.42) and TG (MD = 0.06, 95%CI 0.02 to 0.10), but decreased HDL-C (MD = -0.07, 95%CI -0.11 to -0.04) and LDL-C (MD = -0.11, 95%CI -0.17 to -0.04); but the SUs had no effect on TC (MD = 0.01, 95%CI -0.05 to 0.08), ApoA1 (MD = 0.01, 95%CI -0.03 to 0.04), and Apo B (MD = -0.01, 95%CI -0.05 to 0.03). When compared to metformin, SUs could increase TC and LDL-C; compared to glinides, SUs increased TC and lowered HDL-C; compared to thiazolidinediones, SUs reduced TC, LDL-C, HDL-C, and increase TG. CONCLUSIONS: SUs have a small effect on lipids, although they may statistically increase the level of FFA and TG, and decrease LDL-C and HDL-C.

The quality analysis of literature retrievals of systematic reviews for traditional Chinese medicine.

BACKGROUND: The literature retrievals are still the main problems which limit the quality of systematic review (SR) for traditional Chinese medicine (TCM), and there were still no comprehensive analyses for these problems. The aim of this study is to analyze these problems to guide future SRs for TCM. METHODS: The Cochrane Library (Issue 2, 2009) and the Chinese BioMedical Database (CBM, 1978- 2009.7.31) were comprehensively searched to identify the SRs of TCM. The native literature retrieval rate of the first author, the characteristics of the included databases, the number of the included database, the reporting of literature retrieval strategy, and the reporting of adjuvant search for both the SRs from the CBM and Cochrane Library were analyzed. RESULTS: A total of 341 SRs were included in our analyses, including 245 from the CBM and 96 from the CL. The Chinese-authored SRs ranked the first in median retrieval rate (100%). The Cochrane SRs were significantly superior than the CBM SRs: more searched databases (media: 4 vs. 6, P < 0.001), more precision of retrieval time, more conducting gray literatures searches (47.92% vs. 20.41%) and handing searches (57.29% vs. 54.69%), and more reported retrieval strategies (66.67% vs. 8.16%). CONCLUSIONS: There were significant problems in the literature retrieval of SRs for TCM. In future, when performing any SRs for TCM, sufficient and proper databases, clearly searching strategies and times, proper adjuvant retrievals should be reported. Cochrane SRs might be a better choice.

The Arg399Gln polymorphism in the XRCC1 gene is associated with increased risk of hematological malignancies.

The associations between the Arg399Gln polymorphism in X-ray repair cross-complementing gene 1 (XRCC1) gene and the risk of hematological malignancies have been extensively investigated. However, the results were inconsistent. The objective of the current study is to investigate the association by meta-analysis. We searched PubMed database, Embase database, CNKI database, Wanfang database, and Weipu database, covering all studies until August 7, 2013. Statistical analysis was performed by using the Revman4.2 software and the Stata10.0 software. A total of 27 case-control studies concerning the Arg399Gln polymorphism were included from 26 articles. The results suggested that the Arg399Gln polymorphism was not associated with an increased/decreased risk of hematological malignancies in total analysis (OR = 1.15, 95 % confidence interval (CI) = 0.97-1.35, P = 0.10 for Arg/Gln + Gln/Gln vs. Arg/Arg). In the subgroup analysis by ethnicity and cancer types, significant association was found in Asians (OR = 1.35, 95 % CI = 1.04-1.75, P = 0.03) but not in Europeans (OR = 1.07, 95 % CI = 0.86-1.33, P = 0.56), and in leukemia (OR = 1.25, 95 % CI = 1.02-1.54, P = 0.03) but not in lymphoma (OR = 0.98, 95 % CI = 0.80-1.20, P = 0.84) or myeloma (OR = 1.13, 95 % CI = 0.23-5.69, P = 0.88). The current meta-analysis indicated that the Arg399Gln polymorphism in the XRCC1 gene might be a risk factor for hematological malignancies in Asians or for leukemia. In future, more large-scale case-control studies are needed to validate these results.

The association between gene polymorphisms and risk of nasopharyngeal carcinoma.

Gene polymorphisms have been implicated in increased susceptibility of nasopharyngeal carcinoma, but studies have reported inconclusive results. The present study investigates the relationship between each potential gene polymorphism and the risk of nasopharyngeal carcinoma through a comprehensive series of meta-analyses. Data from Pubmed, CNKI, Wanfang and Weipu databases were collected, evaluated and analyzed. Statistical analysis was performed using the Revman 4.2 and STATA 10.0 softwares. A total of 9,705 nasopharyngeal carcinoma cases and 11,041 controls in 34 case-control studies were identified for data analysis. The results suggested that the Arg399Gln polymorphism of XRCC1 gene, the 1G/2G polymorphism of MMP-1 gene, the RsaI polymorphism of CYP2E1 gene, the -1306C>T polymorphism of MMP-2 gene and the Arg72Pro polymorphism of p53 gene might be related to increased risks of nasopharyngeal carcinoma under different genetic comparison models, while the Arg194Trp and Arg280His polymorphisms of XRCC1 gene and the 309T>G polymorphism of MDM2 gene might not contribute to the risk of nasopharyngeal carcinoma. This current meta-analysis suggests that five polymorphisms might be risk factors for nasopharyngeal carcinoma under different genetic comparison models. Future studies are needed to validate our findings.

Study on the association between the Arg194Trp polymorphism in the XRCC1 gene and the risk of hematological malignancies.

The association between the Arg194Trp polymorphism in the XRCC1 gene and the risk of hematological malignancies has been extensively investigated. However, the results were inconsistent. The objective of the current study is to investigate the association by meta-analysis. We searched the PubMed, Embase, CNKI, Wanfang, and Weipu databases, covering all studies until Aug. 7, 2013. Statistical analysis was performed by using the RevMan4.2 software and the Stata10.0 software. A total of 20 case-control studies concerning the Arg194Trp polymorphism were indentified from 19 articles. In total analysis, our results suggested that the Arg194Trp polymorphism was not associated with an increased/decreased risk of hematological malignancies (odds ratio (OR) = 1.01, 95 % confidence interval (CI) = 0.85-1.22, P = 0.87 for Arg/Trp+Trp/Trp vs. Arg/Arg). In the subgroup analysis by ethnicity, no significant association was found either among Asians (OR = 1.04, 95% CI = 0.84-1.29, P = 0.72) or among Europeans (OR = 1.04, 95% CI = 0.72-1.49, P = 0.83); in the subgroup analyses by cancer types, no significant association was found either among leukemia (OR = 1.10, 95% CI = 0.89-1.35, P = 0.39) or in lymphoma (OR = 0.83, 95% CI = 0.57-1.22, P = 0.35). The current meta-analysis indicated that the Arg194Trp polymorphism in the XRCC1 gene might be not a risk factor for hematological malignancies. In the future, more large-scale case-control studies are needed to validate these results.

The Arg188His polymorphism in the XRCC2 gene and the risk of cancer.

The Arg188His polymorphism in the XRCC2 gene has been suggested as a risk factor for cancer with inconclusive results. The aim of the current study is to investigate the association between the polymorphism with of cancer by meta-analysis. A total of 33 case-control studies from 27 publications were included for data analyses. The results suggested that the Arg188His polymorphism was not associated with increased/decreased risk of cancer in total analysis (Arg/His+His/His vs. Arg/Arg: OR = 0.98, 95% CI = 0.91-1.06). In the subgroup analysis by ethnicity, no statistical significant association was found in Europeans. In the subgroup analysis by cancer types, statistical significant association was found in ovarian cancer but not in other cancers. The current meta-analysis indicated that the Arg188His polymorphism in the XRCC2 gene might be a risk factor for ovarian cancer. In the future, more large-scale case-control studies are needed to validate our results.

The Thr241Met polymorphism in the XRCC3 gene is associated with increased risk of cancer in Chinese mainland populations.

The Thr241Met polymorphism in XRCC3 gene may affect the DNA repair pathways and be associated with the risk of cancer. However, the results of previous studies are inconsistent in Chinese mainland populations. The objective of this study is to investigate the association between the Thr241Met polymorphism in XRCC3 gene and risk of cancer for the Chinese Mainland populations by meta-analysis. We searched PubMed database, Embase database, CNKI database, and Wanfang database, and the last search was updated on July 24, 2013. Statistical analysis was performed using RevMan4.2 and Stata10.0 software. Finally, a total of 23 case-control studies in 23 articles were included. The results suggested a significant association between the Thr241Met polymorphism in XRCC3 gene and cancer risk in Chinese mainland populations (Met/Met + Thr/Met vs. Thr/Thr: OR = 1.25, 95 % CI = 1.02-1.54, P = 0.04). In the subgroup analyses by cancer types, significant associations were found in cervical cancer and nasopharyngeal cancer. The current meta-analysis suggested that the Thr241Met polymorphism in the XRCC3 gene may be a risk factor for cancer in Chinese mainland populations. In the future, more case-control studies are needed to validate these results.

The association between the Arg280His polymorphism in the XRCC1 gene and the risk of hematological malignancies.

The associations between the Arg280His polymorphism in X-ray repair cross-complementing gene 1 (XRCC1 gene) and hematological malignancies have been extensively investigated. However, the results were inconsistent. The objective of the current study was to investigate the associations between the Arg280His polymorphism in XRCC1 gene and the risk of hematological malignancies by meta-analysis. We searched PubMed, Embase, CNKI, Wanfang, and Weipu databases, covering all studies until 07 Aug 2013. Statistical analysis was performed by using the Revman4.2 software and the Stata10.0 software. A total of 2,650 cases and 3,856 controls in 12 case-control studies concerning the Arg280His polymorphism were included. The results suggested that the Arg280His polymorphism might not be associated with risk of hematological malignancies (OR = 1.08, 95%CI = 0.86-1.35, P = 0.50). In the subgroup analyses by cancer types and ethnicity, no significant associations were found among different cancers or different ethnicities. The current meta-analysis indicated that the Arg280His polymorphism in the XRCC1 gene might not be a risk factor for hematological malignancies. In future, more large-scale case-control studies are needed to validate these results.