Usefulness of right ventricular fractional area change to predict death, heart failure, and stroke following myocardial infarction (from the VALIANT ECHO Study)

Severe right ventricular dysfunction independent of left ventricular ejection fraction increased the risk of heart failure (HF) and death after myocardial infarction (MI). The association between right ventricular function and other clinical outcomes after MI was less clear. Two-dimensional echocardiograms were obtained in 605 patients with left ventricular dysfunction and/or clinical/radiologic evidence of HF from the VALIANT echocardiographic substudy (mean 5.0 +/- 2.5 days after MI). Clinical outcomes included all-cause mortality, cardiovascular (CV) death, sudden death, HF, and stroke. Baseline right ventricular function was measured in 522 patients using right ventricular fractional area change (RVFAC) and was related to clinical outcomes. Mean RVFAC was 41.9 +/- 4.3% (range 19.2% to 53.1%). The incidence of clinical events increased with decreasing RVFAC. After adjusting for 11 covariates, including age, ejection fraction, and Killip's classification, decreased RVFAC was independently associated with increased risk of all-cause mortality (hazard ratio [HR] 1.61, 95% confidence interval [CI] 1.31 to 1.98), CV death (HR 1.62, 95% CI 1.30 to 2.01), sudden death (HR 1.79, 95% CI 1.26 to 2.54), HF (HR 1.48, 95% CI 1.17 to 1.86), and stroke (HR 2.95, 95% CI 1.76 to 4.95), but not recurrent MI. Each 5% decrease in baseline RVFAC was associated with a 1.53 (95% CI 1.24 to 1.88) increased risk of fatal and nonfatal CV outcomes. In conclusion, decreased right ventricular systolic function is a major risk factor for death, sudden death, HF, and stroke after MI.     

Block copolymer compatibilization driven frustrated crystallization in electrospun nanofibers of polystyrene/poly(ethylene oxide) blends

The confined crystallization behaviour of poly(ethylene oxide) (PEO) has been studied in electrospun nanofibers of the phase-separated blends of polystyrene (PS) and PEO compatibilized with polystyrene-block-poly(ethylene oxide) (PS-b-PEO) block copolymer. The PS was present as the majority component such that the electrospun nanofibers consisted of PEO domains dispersed in the PS matrix. The phase separation in the blend occurred under the radial constraint of the nanofibers which led to the formation of small-sized fibrillar PEO domains. The use of block copolymer compatibilizer resulted in a noticeable decrease in the PEO domain size in the as-spun nanofibers. Moreover, the decrease in the domain size and domain connectivity was more substantial in the thermally annealed blend nanofibers due to the suppression of the domain coalescence mechanism resulting from the localization of the PS-b-PEO block copolymer at the interface. Consequently, the fraction of PEO domains crystallizing via homogeneous nucleation increased in the compatibilized blend nanofibers due to the presence of higher number of heterogeneity free PEO domains and disruption in their spatial connectivity. Interestingly, in the compatibilized blend nanofibers consisting of low molecular weight PEO, additional crystallization event attributed to surface nucleation was observed. The surface nucleation, plausibly, resulted from the formation of wet-brush structures where the PEO homopolymers homogeneously wet the PEO blocks present at the interface. In such a scenario, the PEO crystallization occurred via surface nucleation at the domain interface. The surface nucleated crystallization was absent in the compatibilized blend nanofibers composed of high molecular weight PEO presumably due to the formation of morphology with dry-brush structures.

Confined crystallization behaviour of poly(ethylene oxide) (PEO) was studied in electrospun nanofibers of the phase-separated blends of polystyrene (PS) and PEO compatibilized with polystyrene-block-poly(ethylene oxide) (PS-b-PEO) block copolymer.     

Is There a Role for Antiplatelet Therapy in Infective Endocarditis? A Review of Current Scientific Evidence

Recently, interest has emerged regarding adjuvant antiplatelet therapy in infective endocarditis (IE) and its impact on clinical outcomes. Despite ongoing research, the role of antiplatelet therapy in this setting remains unclear. Generally, investigations of IE are limited by the low incidence of the disease, practical issues related to diagnosis, and the highly variable latency period between symptom onset and definitive diagnosis. This article reviews the rationale for using antiplatelet therapy in the setting of IE and the contemporary literature that investigates its use.     

Generic outpatient referrals: why don't GPs make them?

AIM: Generic general practitioners' (GPs') referrals to secondary care would facilitate equitable distribution of workload and allow planning to meet access time targets. This study assessed GP's referral patterns across a metropolitan health authority, which has actively encouraged generic referrals. METHODS: A focus group of GPs was used to determine the factors influencing their referral patterns to secondary care for a surgical opinion. A questionnaire was devised based on the factors that emerged from the focus group. All GPs attending continuing-medical-education sessions across Doncaster Health authority were asked to complete this questionnaire. RESULTS: Of the 79 GPs surveyed, 78 completed the questionnaire. Of them, 22% stated that they made generic referrals rather than to an individual surgeon. Almost four of five GPs made referrals specifically to a named surgeon. A total of 43% of the GPs who referred to a named surgeon ranked perceived clinical skills/ competence as the most important factor. The other factors that influenced their decision in order of importance were waiting times (19%), personal rapport with consultant (12.6%) and feedback from patients (12.6%). CONCLUSION: Despite encouragement by secondary care and the local health authority, 78% of GPs in the Doncaster area do not make generic referrals. This has to be taken into account in planning service delivery.     

Alterations of transforming growth factor beta receptor II, insulin growth factor receptor II genes in microsatellite unstable prostate carcinomas

DNA from 45 primary prostate tumors and corresponding normal tissues were analyzed to detect whether the alterations of transforming growth factor beta receptor II (TGFbetaRII) and insulin growth factor receptor II (IGFRII) are associated with microsatellite instability (MSI). We identified that 25 tumors were microsatellite unstable (55%). The remaining 20 tumors are found to be microsatellite stable. Loss of heterozygosity (LOH) was also tested at various loci. Results indicate that in case of TGFbetaRII, the rate of frame-shift mutation depends on the number of polyadenine [poly(A)] tracts. Twelve percent of the tumors had frame-shift alteration at BAT-RII locus which has 10 poly(A) repeats. Twenty percent of the tumors had frame-shift at BAT-25 locus which has 25 poly(A) repeats. In addition, IGFRII gene was examined for the presence of mutation in the repetitive sequences. Seven of the 25 tumors showed deletion of a G within eight poly(G) repeats. Besides these changes there were two tumors which showed a novel insertion of A within this poly(G) repeat making a change in 9 samples (R4, 36%). On the other hand, 4 tumors showed changes within the 5CT repeats. In addition, 3 tumors showed another novel insertion of C within the CT repeats.