BackgroundP-wave indices are appealing markers for predicting atrial fibrillation (AF) recurrences post ablation.ObjectiveThis study evaluates the value of P wave indices to predict recurrences post pulmonary vein isolation (PVI) in patients with paroxysmal AF.MethodsWe selected 198 patients (57 ± 8 years, 150 males) with symptomatic drug-refractory paroxysmal AF undergoing PVI in our hospital. A 12-lead electrocardiogram was used to measure P wave duration in lead II, P wave terminal force (PWTF) in lead V1, P wave axis and dispersion.ResultsDuring a follow-up of 9 ± 3 months, recurrences occurred in 60 (30.3%) patients. The patients that had AF recurrence had longer mean P wave duration (122.9 ± 10.3 vs 104.3 ± 14.2 ms, p < 0.001), larger P wave dispersion (40.7 ± 1.7 ms vs 36.6 ± 3.2 ms, p < 0.001). P wave duration ≥ 125 ms has 60% sensitivity, 90% specificity, positive predictive value (PPV) of 72% and negative predictive value (NPV) of 83.7%, whereas P wave dispersion ≥ 40 ms has 78% sensitivity, 67% specificity, PPV of 51% and NPV of 87.6% 48/66 (72.7%) patients with PWTF ≤ - 0.04 mm/second vs 12/132(9%) with PWTF > -0.04 mm/second showed recurrence of AF (p < 0.001). P wave axis was not different between two groups. On multivariate analysis, P wave indices were not independent from left atrial size and age.ConclusionsP wave duration ≥ 125 ms, P wave dispersion ≥ 40 ms and PWTF in V1 ≤ - 0.04 mm/sec are good clinical predictors of AF recurrences post PVI in patients with paroxysmal atrial fibrillation; however they were not independent from left atrial size and age.

To obtain comprehensive knowledge of the interfacial effect on the impact performance of sisal fiber reinforced epoxy composites, the fiber surface was modified in different ways prior to compounding. By using a surface tensiometer and dynamic mechanical analyzer, interfacial interactions in the composites were characterized. The results indicated that the chemical treatments brought about strong bonding between sisal bundles and the epoxy matrix. The subsequent impact tests revealed that the microfailure mechanism involved is a function of interfacial adhesion and fiber length continuity (i.e., continuous or discontinuous fiber). In the case of unidirectional laminates, an optimum fiber treatment should be able to result in an increased affinity between fiber bundles and matrix and a decreased intercellular adhesion. In this way, extension and uncoiling of the spirally arranged microfibrils, a main energy consumption process of plant fibers, can impart significant toughness to the composites. For short fiber composites, the interfacial strength should be properly tailored so as to increase energy dissipation through debonding and pullout of fiber bundles.

This study aimed to examine effects of adjunctive baicalin therapy to ampicillin for experimental bacterial meningitis in rabbits. After Escherichia Coli inoculation, mean leukocyte counts, concentrations of protein, tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1) and lactate in cerebrospinal fluid (CSF), brain water content and mean arterial and intracranial pressures substantially increased in the meningitis group. Ampicillin alone for 5 h markedly exacerbated the enhanced leukocyte counts and protein concentration, and showed no significant effect on the elevated CSF TNF-alpha, IL-1 and lactate concentration, mean arterial and intracranial pressures, and brain water content. Baicalin (7-D-glucuronic acid-5,6-dihydroxyflavone, C(21)H(18)O(11)) completely counteracted ampicillin-induced exacerbation, and further alleviated the enhanced mean leukocyte counts and protein concentration when combined with ampicillin. Adjunctive baicalin also significantly ameliorated the elevated CSF TNF-alpha, IL-1 and lactate concentration, mean arterial and intracranial pressures, and brain water content. Baicillin, as an adjunctive treatment exerted multiple therapeutic effects in experimental bacterial meningitis.

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