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Background and Purpose: Whether imaging parameters would independently predict stroke recurrence in low-risk minor ischemic stroke (MIS) or transient ischemic attack (TIA) according to traditional score system (such as ABCD 2 score, which was termed on the basis of the initials of the five factors: age, blood pressure, clinical features, duration, diabetes) remains unclear. We sought to evaluate the association between imaging parameters and 1-year stroke recurrence in patients with TIA or MIS in different risk stratum stratified by ABCD 2 score. Methods: We included patients with TIA and MIS (National Institutes of Health Stroke Scale score ≤3) with complete baseline vessel and brain imaging data from the Third China National Stroke Registry III. Patients were categorized into different risk groups based on ABCD 2 score (low risk, 0–3; moderate risk, 4–5; and high risk, 6–7). The primary outcome was stroke recurrence within 1 year. Multivariable Cox proportional-hazards regression models were used to assess whether imaging parameters (large artery stenosis, infarction number) were independently associated with stroke recurrence. Results: Of the 7140 patients included, 584 patients experienced stroke recurrence within 1 year. According to the ABCD 2 score, large artery stenosis was associated with higher stroke recurrence in both low-risk (adjusted hazard ratio, 1.746 [95% CI, 1.200–2.540]) and moderate-risk group (adjusted hazard ratio, 1.326 [95% CI, 1.042–1.687]) but not in the high-risk group ( P >0.05). Patients with multiple acute infarctions or single acute infarction had a higher risk of recurrent stroke than those with no infarction in both low- and moderate-risk groups, but not in the high-risk group. Conclusions: Large artery stenosis and infarction number were independent predictors of 1-year stroke recurrence in low-moderate risk but not in high-risk patients with TIA or MIS stratified by ABCD 2 score. This finding emphasizes the importance of early brain and vascular imaging evaluation for risk stratification in patients with TIA or MIS.

The protein-mediated bidirectional electron transfer (ET) is the foundation of protein molecular wire, and plays an important role in the rapid detection of oxo-guanine-adenine DNA mismatches by MutY glycosylase. However, the influences of structural transitions on bidirectional ET are still not clear. In this work, the modified through-bond coupling (MTBC) model was further refined to correlate the structural transition and ET rate more quantitatively. With this model, various polyglycine structures (310-helix, α-helix, β-sheets, linear, polyproline helical I and II) were studied to explore the influences of structural transitions on bidirectional ET. It was found that the HOMO-LUMO gaps (ΔE) in CN (from the carboxyl to amino terminus) direction are much lower than that in opposite direction, except for polypro I. However, with the equal tunneling energy, the differences between bidirectional ET rates are slight for all structures. In structural transitions, we found that the ET rates are not only affected by the Ramachandran angles, but also correlated to the alignment of C = O vectors, the alignment of peptide planes and the rearrangement of other structure factors. The detailed information can be used to rationalize the inhomogeneous ET across different protein structures and design more efficient protein molecular wires.

The association between the methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism and ischemic stroke (IS) has been extensively studied; however, the results from genetic association studies have been inconsistent even in the Chinese population. As far as we know, there was no previous meta-analysis concerning this association in the Chinese population. Therefore, the aim of our meta-analysis was to further evaluate the association in the Chinese population.We collected all of the relevant studies from Pubmed, OVID, Embase, Chinese Wan Fang database, CNKI, Chongqing VIP database and CBM up to August 2014. The available data was analyzed by Stata (version 12.0). We used odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to present the strength of the association. Heterogeneity was evaluated by the Q-test and I(2) statistic. Different genetic models, subgroup analysis, publication bias and sensitivity analysis were used to improve the comprehensive understanding.The results showed a significant association between the MTHFR gene C677T polymorphism and IS in six genetic models (additive model: OR = 1.34, 95%CI: 1.17 ∼ 1.54, p0.001; dominant model: OR = 1.44, 95% CI:1.26 ∼ 1.64, p0.001; recessive model: OR = 1.45, 95% CI: 1.15 ∼ 1.83, p = 0.001; heterozygote model: OR = 1.35, 95% CI: 1.18 ∼ 1.55, p0.001; homozygote model: OR = 1.80, 95% CI: 1.34 ∼ 2.41, p0.001; and allelic model: OR = 1.34, 95% CI: 1.17 ∼ 1.53, p0.001) based on the overall population, as well as subgroup analysis. In addition, the similar results were obtained in the sensitivity analysis based on studies with the high quality.This meta-analysis presented a significant association between the MTHFR gene C677T polymorphism and IS, the T allele might be a risk factor for IS in the Chinese population.