Modification of Low Refractive Index Polycarbonate for High Refractive Index Applications

Polycarbonates and polythiourethanes are the most popular materials in use today, for optical applications. Polycarbonates are of two types which fall in the category of low refractive index and medium refractive index. The present paper describes the conversion of low refractive index polycarbonates into high refractive index material by the use of a high refractive index monomer, polythiol, as an additive. Novel polycarbonates, where the properties of refractive index and Abbe number can be tailor made, have been obtained. Thermal studies and refractive index determination indicate the formation of a new polymer with improved properties and suitable for optical applications

B-type natriuretic peptide clinical activation in aortic stenosis : impact on long-term survival

Objectives : This study was conducted to define the association between serum B-type natriuretic peptide (BNP) activation and survival after the diagnosis of aortic stenosis (AS).Background : In AS, the link between BNP levels and clinical outcome is in dispute. Failure to account for the normal shifting of BNP ranges with aging in men and women, not using hard endpoints (survival), and not enrolling large series of patients have contributed to the uncertainty.Methods : A program of prospective measurement of BNP levels with Doppler echocardiographic AS assessment during the same episode of care was conducted. BNP ratio (measured BNP/maximal normal BNP value specific to age and sex) >1 defined BNP clinical activation.Results : In 1,953 consecutive patients with at least moderate AS (aortic valve area 1.03 ± 0.26 cm2; mean gradient 36 ± 19 mm Hg), median BNP level was 252 pg/ml (interquartile range: 98 to 592 pg/ml); BNP ratio 2.46 (interquartile range 1.03 to 5.66); ejection fraction (EF) 57% ± 15%, and symptoms present in 60% of patients. After adjustment for all survival determinants, BNP clinical activation (BNP ratio >1) independently predicted mortality after diagnosis (p 2 (HR: 0.56; 95% CI: 0.47 to 0.66; p < 0.0001).Conclusions : In this large series of patients with AS, BNP clinical activation was associated with excess long-term mortality incrementally and independently of all baseline characteristics. Higher mortality with higher BNP clinical activation, even in asymptomatic patients, emphasizes the importance of appropriate clinical interpretation of BNP levels in managing patients with AS

Increased risk of acute kidney injury in patients undergoing tricuspid valve surgery

OBJECTIVES We aimed to determine which patients undergoing tricuspid valve (TV) surgery are at increased risk for acute kidney injury (AKI). METHODS We reviewed 951 patients [mean age 67 ± 13 years, 573 (60%) female] having TV surgery between 2000 and 2007. Analysis focused on clinical outcome; AKI was defined by the consensus RIFLE criteria (risk, injury, failure). RESULTS Surgical procedures included isolated TV surgery in 224 (24%) and TV surgery in conjunction with another cardiac operation in 727 (76%) patients. TV surgery involved redo surgery in 395 (42%). The incidence of postoperative AKI was 30% (n = 285), and 75 (7.9%) of these patients required renal replacement therapy. AKI stratified by increased RIFLE class was associated with worse postoperative outcomes (prolonged intubation, length of hospital stay and mortality; P < 0.001 for each variable). For patients with AKI, odds ratio for mortality was 4.2 [95% confidence interval (CI) 3.2-5.4, P < 0.001; area under receiver operating curves 0.85 (95% CI 0.80-0.91)], and 2.3 (95% CI 1.9-2.9, P < 0.001) for prolonged intubation for each increase in RIFLE class. Independent risk factors for AKI were older age, male gender, previous surgery, preoperative anaemia, length of cardiopulmonary bypass and TV replacement. Importantly, preoperative creatinine and pulmonary artery pressure were not independently associated with AKI. CONCLUSIONS TV surgery carries a high incidence of postoperative AKI that is associated with adverse outcome. The use of the RIFLE criteria allows comparison with prior studies and is an important predictor of early mortality. The estimation of patient risk for AKI should be based on multivariable predictio

Late outcome of repair of congenital coronary artery fistulas—a word of caution

ObjectivesWe reviewed our experience with repair of congenital coronary artery fistulas.MethodsFrom June 1983 to December 2009, 46 patients (median age, 59 years; range, 1-84 years) underwent surgical repair. The presenting symptoms included angina in 16 patients (35%), congestive heart failure in 11 (24%), and bacterial endocarditis in 5 (11%). Preoperatively, 9 patients (20%) had at least moderate tricuspid regurgitation. Coronary artery dominance was right in 38 patients (83%). Coronary artery aneurysms were found in 8 patients (17%). The most common pattern was right coronary artery-to-coronary sinus fistula (18 patients, 39%); 11 patients had (23%) more than 1 fistula. One patient had undergone previous coil embolization.ResultsCardiopulmonary bypass was used in 39 patients (85%), with extracardiac and intracardiac repair performed in 30 (65%) and 16 (35%), respectively. The most common associated procedures were coronary artery bypass in 13 patients (28%). Early mortality occurred in 1 patient (2%). Postoperative myocardial infarction occurred in 5 patients (11%); 4 of these patients underwent simple ligation or division of their fistulas. The mean follow-up was 6 ± 5.8 years (maximum, 22 years). Late mortality occurred in 11 patients (24%). Two patients underwent reoperation for severe tricuspid regurgitation. Survival was significantly reduced compared with the age- and gender-matched population (P = .03). Residual fistulas were detected in 3 patients (6%), with no reintervention needed.ConclusionsPerioperative myocardial infarction is an important complication of ligation of coronary artery fistulas and can contribute to reduced late survival. The tricuspid valve should be evaluated carefully at repair because of the relatively high rate of residual regurgitation in survivors

Sex differences and survival in adults with bicuspid aortic valves : verification in 3 contemporary echocardiographic cohorts

Background-—Sex-related differences in morbidity and survival in bicuspid aortic valve (BAV) adults are fundamentally unknown. Contemporary studies portend excellent survival for BAV patients identified at early echocardiographic-clinical stages. Whether BAV adults incur a survival disadvantage throughout subsequent echocardiographic-clinical stages remains undetermined. Methods and Results-—Analysis was done of 3 different cohorts of consecutive patients with echocardiographic diagnosis of BAV identified retrospectively: (1) a community cohort of 416 patients with first BAV diagnosis (age 35 21 years, follow-up 16 7 years), (2) a tertiary clinical referral cohort of 2824 BAV adults (age 51 16 years, follow-up 9 6 years), and (3) a surgical referral cohort of 2242 BAV adults referred for aortic valve replacement (AVR) (age 62 14 years, follow-up 6 5 years). For the community cohort, 20-year risks of aortic regurgitation (AR), AVR, and infective endocarditis were higher in men (all P=0.04); for a total BAV-related morbidity risk of 52 4% vs 35 6% in women (P=0.01). The cohort’s 25-year survival was identical to that in the general population (P=0.98). AR independently predicted mortality in women (P=0.001). Baseline AR was more common in men (P=0.02) in the tertiary cohort, with 20-year survival lower than that in the general population (P<0.0001); age-adjusted relative death risk was 1.16 (95% confidence interval [CI] 1.05-1.29) for men versus 1.67 (95% CI 1.38-2.03) for women (P=0.001). AR independently predicted mortality in women (P=0.01). Baseline AR and infective endocarditis were higher in men (both =0.001) for the surgical referral cohort, with 15-year survival lower than that in the general population (P<0.0001); age-adjusted relative death risk was 1.34 (95% CI 1.22-1.47) for men versus 1.63 (95% CI 1.40-1.89) for women (P=0.026). AR and NYHA class independently predicted mortality in women (both P=0.04). Conclusions-—Within evolving echocardiographic-clinical stages, the long-term survival of adults with BAV is not benign, as both men and women incur excess mortality. Although BAV-related morbidity is higher in men in the community, and AR and infective endocarditis are more prevalent in men, women exhibit a significantly higher relative risk of death in tertiary and surgical referral cohorts, which is independently associated with A

Comparaison de deux méthodes de sélection classique avec l'haplodiploïdisation pour la résistance à la mouche de Hesse chez le blé tendre (Triticum aestivum)

L'efficacité des méthodes classiques et alternatives d'amélioration génétique repose sur l'évolution de la variabilité génétique des populations ségrégatives sous sélection. L'objectif de cette étude est de comparer l'évolution de la fréquence des gènes de résistance à la mouche de Hesse (Mayetiola destructor) sous deux méthodes classiques de sélection en comparaison avec la méthode de l'haplodiploïdisation. Les distributions et les proportions observées du caractère "résistance à la mouche de Hesse" ont été évaluées pour des lignées produites par la méthode de filiation unipare (FUP), la méthode " bulk " et l'haplodiploïdisation (DH) de quatre populations hybrides de blé tendre (Triticum aestivum). Ces populations sont issues des croisements entre des parents résistants à la mouche de Hesse marocaine et des parents sensibles mais adaptés aux conditions marocaines. Les résultats ont montré un effet marqué de la méthode d'amélioration génétique. En effet, malgré leur avancement à la génération F6, les lignées produites par les méthodes FUP et " bulk " présentent toujours un taux non négligeable d'hétérozygotie pour ce caractère alors que la méthode DH a abouti à une homozygotie parfaite. Les proportions de résistance observées chez les lignées FUP et haploïdes doublées sont approximativement les mêmes que celles théoriquement attendues. Cependant, la méthode " bulk " a permis une sélection naturelle au champ qui a favorisé le caractère résistant de manière significativeThe relative usefulness of conventional and alternative breeding methods relies on the evolution of genetic variability in segregating populations undergoing selection. The objective of this study was to compare the frequencies of genetic resistance to Hessian fly (Mayetiola destructor) in populations generated by two conventional breeding methods in comparison with lines advanced through doubled haploid method. Distribution and proportions of Hessian fly resistance were evaluated in four populations of bread wheat lines advanced through 'Single Seed Descent' (SSD), 'Bulk', and doubled-haploid (DH) methods. These populations were all derived from crosses involving resistant parents and susceptible lines adapted to Moroccan conditions. The results of this study have shown a clear effect of the breeding method. The Bulk and SSD (F6) derived lines have shown a substantial residual heterozygocity while DH method has produced completely homozygous material. The observed proportions of resistance did not deviate from expected in the populations of lines derived through SSD and DH methods while evidence of natural selection for resistance was significant in the lines derived through the Bulk method

CD40 gene polymorphism and its expression in children with Kawasaki disease from North India: a preliminary case–control study and meta-analysis

IntroductionCD40 gene single-nucleotide polymorphisms (SNPs) have been associated with susceptibility and development of coronary artery abnormalities (CAAs) in children with Kawasaki disease (KD) in Japanese, Chinese, and Taiwanese populations. However, data on SNPs of the CD40 gene in patients with KD from the Indian subcontinent are not available. We studied the CD40 gene polymorphisms and its expression in children with KD from North India.MethodsSNPs of the CD40 gene (rs4810485, rs1535045) were studied using Sanger sequencing. CD40 expression was studied by flow cytometry. Meta-analysis was carried out to assess the role of both SNPs of the CD40 gene in KD. GRADEpro GDT software (v.3.2) was used to assess the “certainty of evidence.”ResultsForty-one patients with KD and 41 age-, sex-matched febrile controls were enrolled. However, none of the alleles and genotypes of the CD40 gene were found to be associated with KD. CD40 expression was higher in KD and in KD with CAAs compared to controls, but it failed to reach statistical significance. In a meta-analysis, the T allele of rs153045 was found to be significantly associated with KD (OR = 1.28; 95% confidence interval (: 1.09–1.50; p = 0.002). The GRADE of evidence for this outcome, however, is of “ very low certainty.”ConclusionThe present study found no association between SNPs (rs4810485 and rs153045) and susceptibility to KD. This could be a reflection of a modest sample size. CD40 expression was higher in KD and in KD with CAAs. In the meta-analysis, the T allele of rs153045 was significantly associated with KD. Our study confirms a significant genetic heterogeneity in KD among different ethnicities

Left atrial size is a potent predictor of mortality in mitral regurgitation due to flail leaflets results from a large international multicenter study

Background-Left atrium (LA) enlargement is common in organic mitral regurgitation (MR) and is an emerging prognostic indicator. However, outcome implications of LA enlargement have not been analyzed in the context of routine clinical practice and in a multicenter study. Methods and Results-The Mitral Regurgitation International DAtabase (MIDA) registry enrolls patients with organic MR due to flail leaflets, diagnosed in routine clinical practice, in 5 US and European centers. We investigated the relation between LA diameter and mortality under medical treatment and after mitral surgery in 788 patients in sinus rhythm (64±12 years; median LA, 48 [43 to 52] mm). LA diameter was independently associated with survival after diagnosis (hazard ratio, 1.08 [1.04 to 1.12] per 1 mm increment). Compared with patients with LA<55 mm, those with LA â¥55 mm had lower 8-year overall survival (P<0.001). LA â¥55 mm independently predicted overall mortality (hazard ratio, 3.67 [1.95 to 6.88]) and cardiac mortality (hazard ratio, 3.74 [1.72 to 8.13]) under medical treatment. The association of LA â¥55 mm and mortality was consistent in subgroups. Similar excess mortality associated with LA â¥55 mm was observed in asymptomatic and symptomatic patients (P for interaction, 0.77). In patients who underwent mitral surgery, LA â¥55 mm had no impact on postoperative outcome (P<0.20). Mitral surgery was associated with greater survival benefit in patients with LA â¥55 mm compared with LA <55 mm (P for interaction, 0.008). Conclusions-In MR caused by flail leaflets, LA diameter â¥55 mm is associated with increased mortality under medical treatment, independent of the presence of symptoms or left ventricular dysfunction. © 2011 American Heart Association, Inc