Electron scale coherent structure as micro accelerator in the Earth's magnetosheath.

Turbulent energy dissipation is a fundamental process in plasma physics that has not been settled. It is generally believed that the turbulent energy is dissipated at electron scales leading to electron energization in magnetized plasmas. Here, we propose a micro accelerator which could transform electrons from isotropic distribution to trapped, and then to stream (Strahl) distribution. From the MMS observations of an electron-scale coherent structure in the dayside magnetosheath, we identify an electron flux enhancement region in this structure collocated with an increase of magnetic field strength, which is also closely associated with a non-zero parallel electric field. We propose a trapping model considering a field-aligned electric potential together with the mirror force. The results are consistent with the observed electron fluxes from ~50 eV to ~200 eV. It further demonstrates that bidirectional electron jets can be formed by the hourglass-like magnetic configuration of the structure.

Association between the IL1B, IL1RN polymorphisms and COPD risk: a meta-analysis.

The interleukin-1 (IL-1) gene polymorphisms have been implicated in chronic obstructive pulmonary disease (COPD) risk, but results are controversial. We aimed to conduct a meta-analysis to address this issue. Odds ratio (OR) and 95% confidence interval (CI) were used to investigate the strength of the association. The meta-analysis revealed no association between the IL1B (-511), (-31), (+3954) polymorphisms and COPD risk. However, stratification by ethnicity indicated that the T allele carriers of the IL1B (-511) polymorphism and the C allele carriers of the IL1B (-31) variant were associated with an increased risk for developing COPD in East Asians (OR = 1.61, 95% CI: 1.13-2.31, Pz = 0.009 and OR = 1.55, 95% CI: 1.14-2.11, Pz = 0.006, respectively). The meta-analysis revealed a significant association between the IL1RN (VNTR) polymorphism and COPD risk in all study subjects and East Asians under homozygote model (22 vs. LL: OR = 3.16, 95% CI: 1.23-8.13, Pz = 0.017 and OR = 3.20, 95% CI: 1.13-9.12, Pz = 0.029, respectively). Our meta-analysis suggests that the IL1B (-511), (-31) and IL1RN (VNTR) polymorphisms are associated with COPD risk in East Asians. There is no association between the IL1B (+3954) polymorphism and COPD risk. Further studies should be performed in other ethnic groups besides East Asians.

The regulated upon activation normal T-cell expressed and secreted (RANTES) -28C/G and -403G/A polymorphisms and asthma risk: a meta-analysis.

BACKGROUND AND OBJECTIVES: Genetic studies have revealed that the regulated upon activation normal T-cell expressed and secreted (RANTES) -28C/G and -403G/A polymorphisms are associated with asthma risk, but contradictory findings have also been reported. Therefore, we undertook a meta-analysis on this topic. METHODS: The PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases were used to identify relevant studies published in the medical literature from 1990 to March 26, 2014. Nine studies (containing 2,103 cases and 2,876 controls) investigated the -28C/G polymorphism, and 11 studies (including 2,015 cases and 1,909 controls) assessed the -403G/A polymorphism. RESULTS: The pooled results demonstrated that the -28C/G polymorphism was not associated with asthma risk in the overall populations (Caucasians, Asians, and a mixed population). However, in subgroup analysis according to age, the -28G allele was associated with an increased risk of asthma in children (odds ratio [OR] 1.27, 95 % confidence interval [CI] 1.03-1.57, P value for heterogeneity [P het] = 0.163, P value for the overall effect [P z] = 0.028). When we further stratified the studies performed in children on the basis of ethnicity, we found that the -28G allele was associated with an increased risk of asthma in Asian children (OR 1.28, 95 % CI 1.02-1.62, P het = 0.127, P z = 0.035), but not in Caucasian children (OR 1.20, 95 % CI 0.68-2.12, P het = 0.137, P z = 0.530). In subgroup analysis by asthma phenotype, no association between either atopic or non-atopic asthma and the -28C/G polymorphism was identified. For the -403G/A polymorphism, meta-analysis showed no association with asthma risk in the overall populations (Caucasians, Asians, and black people). In subgroup analyses by age, ethnicity, and asthma phenotype, we still did not find any association between the -403G/A polymorphism and asthma. CONCLUSION: Current findings suggest an association between the -28G allele and asthma risk in Asian children but not in Caucasian children.

Association between the ghrelin Leu72Met polymorphism and type 2 diabetes risk: a meta-analysis.

AIMS: Data on the association between the ghrelin Leu72Met polymorphism and type 2 diabetes are conflicting. A meta-analysis was performed on this topic. METHODS: We searched for case-control studies using electronic databases (Medline and PubMed) and reference lists of studies. Odds ratios (OR) and 95% confidence intervals (CI) assuming dominant, recessive and homozygote comparison genetic models were calculated. RESULTS: Six case-control studies involving a total of 3417 cases and 3081 controls were included in this meta-analysis. No association was found between the ghrelin Leu72Met polymorphism and type 2 diabetes risk in the overall population in dominant, recessive and homozygote comparison models. However, in subgroup analyses stratified by ethnicity, we found that the risk for type 2 diabetes was decreased in subjects with Met72+ genotypes in Caucasians (OR=0.79, 95% CI: 0.64-0.98, P(z)=0.030). CONCLUSION: The ghrelin Leu72Met polymorphism was protective against type 2 diabetes in Caucasians. Future studies performed in larger sample size are needed to allow a more definitive conclusion.

Association of interleukin-1 gene polymorphisms with multiple sclerosis: a meta-analysis.

BACKGROUND: Dysregulated levels of interleukin-1 (IL-1) were observed in patients with multiple sclerosis (MS). Previous studies have provided conflicting evidence implicating the IL-1 gene polymorphisms in MS risk. METHODS: A meta-analysis of 16 case-control studies involving 3,482 cases and 3,528 controls was conducted to evaluate this association. RESULTS: No association was found between the IL-1α -889 (rs1800587), IL-1α +4,845 (rs17561), IL-1ß -511 (rs16944), IL-1ß +3,953 (rs1143634), IL-1ra variable number tandem repeat (VNTR) polymorphisms and MS risk. However, in subgroup analyses for the IL-1ra VNTR polymorphism, we found that individuals carrying the 2 allele had a 32 % increased risk for bout-onset MS (relapsing remitting and secondary progressive MS) when compared to the LL homozygotes (OR = 1.32, 95 % CI = 1.06-1.66, P (z) = 0.014). CONCLUSION: Common variants in the IL-1 region are not associated with MS risk but our data suggest that the IL-1ra VNTR polymorphism might be associated with bout-onset MS subtype.