Synthesis of polyurethanes by polycondensation of active biscarbonates of diols with hexamethylenediamine and its derivatives

A new synthesis pathway to polyurethanes (PURs) by polycondensation of active carbonates of diols with hexamethylenediamine was investigated in detail including model studies. It has been shown that high-molecular-weight PURs (η_red ≤ 3,8 dL/g) can be obtained under optimum reaction conditions. Salts of the diamine and its N,N′-trimethyl-silylated derivative were also used for the synthesis of film- and fiber-forming PURs.     

Single‐Center Experience With HeartMate II Left Ventricular Assist Device Explantation

In patients with continuous flow left ventricular assist devices (CF‐LVADs) myocardial recovery is uncommon. Given the heterogeneity of the population implanted and low incidence of recovery, the discovery of native left ventricular (LV) recovery and criteria for explantation of CF‐LVAD system is not clearly determined. We sought to analyze the characteristics of the patients who underwent CF‐LVAD explantation at our institution. Prospectively collected data on patients supported with CF‐LVADs were reviewed retrospectively. Patients who underwent CF‐LVAD explants were identified and their characteristics were analyzed with a focus on patient presentation and determinants of explantability. From November 2006 to June 2014, 223 patients (181 male, 42 female) underwent implantation of HeartMate II LVAD. Seven female (16.7%) and one male (0.6%) patients were explanted (P < 0.001). Mean age was 43 ± 9 years and etiology for cardiomyopathy was ischemic in three (37.5%) patients, nonischemic in four (50%) patients, and mixed in the one (12.5%) male patient of the cohort. Five (62.5%) patients presented acutely with significant hemolysis, and were found to have LV improvement as well as reduced, absent, or reversed diastolic flow velocities on echocardiography. Overall, mean lactate dehydrogenase level before explantation was 1709 ± 1168 U/L compared to the mean baseline level of 601 ± 316 U/L (P = 0.048). Mean LV ejection fraction (LVEF) improved from 17 ± 7% preimplant to 56 ± 11% pre‐explantation (P < 0.001). Median number of days on CF‐LVAD support was 870 (interquartile range, 209–975) while mean duration of follow‐up after the CF‐LVAD explantation was 276 ± 240 days. Mean LVEF dropped from 46 ± 19% postexplantation to 34 ± 10% during the most recent follow‐up (P = 0.015). At our institution, patients who underwent LVAD explants were predominantly women with nonischemic cardiomyopathy. Clinical evidence of hemolysis and echocardiographic evidence of reduced or absent diastolic flow velocities were common findings in these patients. Over time, patient's native LV function declined in the absence of LVAD (after LVAD explantation). Significant challenges remain in predicting LV recovery and identifying those individuals who have recovered myocardial function significant enough to be explanted.     

Electromagnetic interference between implantable cardiac devices and continuous-flow left ventricular assist devices: a review

Journal of Interventional Cardiac Electrophysiology - Many patients with continuous-flow left ventricular assist devices (CF-LVAD) have other, co-existing implantable cardiac devices. While such...     

Childhood asthma in Batumi,Georgia: Prevalence and environmental correlates

Objective: A relative lack of data for Eastern Europe and unknown epidemiology of childhood asthma in Batumi (Georgia) justified a study aimed at determining the prevalence of physician-diagnosed asthma and related respiratory conditions, a comparison of the prevalence of these conditions between urban and rural children, and identification of their environmental correlates. Methods: Subjects of the cross-sectional population-based study were 3238 urban and 2081 rural children aged 5–17 years whose respiratory status was assessed using the ISAAC questionnaire. Results: The overall prevalence of asthma was larger in rural children than in urban children (2.8% vs. 1.8%, respectively; p = 0.01). Spastic bronchitis occurred with similar frequency in urban (7.8%) and rural children (6.5%). Compared with urban children, rural subjects had dry cough at night (13.1 vs 8.2%, p < 0.001) and attacks of dyspnea (4.7 vs 2.4%, p < 0.001) more often. The prevalence of other symptoms did not differ significantly between urban and rural subjects. Results of multivariate analyses showed that both asthma and spastic bronchitis were associated (p < 0.05) with parental history of asthma, dampness in the house, and poor financial standing of the family. In addition, asthma was related to coal/wood-based heating whereas spastic bronchitis was associated with passive smoking and lower parental education. Conclusions: The findings show a low prevalence of ever-diagnosed asthma in the examined population. Nosological tradition and similar correlates of asthma and spastic bronchitis suggest that some cases of asthma might be included in the diagnostic category of spastic bronchitis.     

Antioxidant and anti-inflammatory activities of quercetin 7-O-β-D-glucopyranoside from the leaves of Brasenia schreberi

Brasenia schreberi Gmel. (Cabombaceae) is an aquatic plant that grows in eastern Asia, Australia, Africa, and North and Central America. B. schreberi leaf extracts were obtained by sequential solvent extraction with dichloromethane, methanol, and water. The antioxidant potential of each extract was assessed by using the oxygen radical absorbance capacity (ORAC) assay. With this method, methanol and water extracts were found to be active with mean ± standard deviation values of 7 ± 2 and 5.1 ± 0.5?μmol Trolox? equivalents (TE)/mg, respectively. Two major phenolic compounds, quercetin-7-O-β-D-glucopyranoside and gallic acid, were respectively isolated from the methanolic and water extracts. Both compounds exhibited antioxidant activities, in particular quercetin-7-O-β-D-glucopyranoside (ORAC value, 18 ± 4 μmol TE/μmol). In contrast to its well-known antioxidant homologue quercetin, quercetin-7-O-β-D-glucopyranoside does not inhibit growth of human fibroblasts (WS-1) or murine macrophages (RAW 264.7). Some flavonoids have been reported to possess beneficial effects in cardiovascular and chronic inflammatory diseases associated with overproduction of nitric oxide. Quercetin-7-O-β-D-glucopyranoside possesses anti-inflammatory activity, inhibiting expression of inducible nitric oxide synthase and release of nitric oxide by lipopolysaccharide-stimulated RAW 264.7 macrophages in a dose-dependent manner. Quercetin-7-O-β-D-glucopyranoside also inhibited overexpression of cyclooxygenase-2 and granulocyte macrophage-colony-stimulating factor.