Search

Two approaches to determining the second-order polarizabilities of nitropyridine derivatives, electric-field-induced second-harmonic generation (EFISH) and solvachromic, arecompared. The results show that both methods produce the same values within theexperimental errors. The solvachromatic method results in important molecular parameters. The EFISH approach produces second-order polarizabilities which follow the two-level theoretical dispersion.

Background: The early and accurate diagnosis of acute myocardial infarction (AMI) is an important medical and economic challenge. We aimed to prospectively evaluate the performance of the new European Society of Cardiology rapid 0-hour/3-hour (0 h/3 h) rule out protocol for AMI.Methods: We enrolled 2,727 consecutive patients presenting with suspected AMI without persistent ST-segment elevation to the emergency department in a prospective international multicenter study. The final diagnosis was adjudicated by 2 independent cardiologists. The performance of the 0 h/3 h rule out protocol was evaluated using 4 high-sensitivity (primary analysis) and 3 sensitive cardiac troponin (cTn) assays.Results: Acute myocardial infarction was the final diagnosis in 473 patients (17.3%). Using the 4 high-sensitivity cTn assays, the 0-hour rule out protocol correctly ruled out 99.8% (95% [confidence interval] CI, 98.7%-100%), 99.6% (95% CI, 98.5%-99.9%), 100% (95% CI, 97.9%-100%), and 100% (95% CI, 98.0%-100%) of late presenters (>6 h from chest pain onset). The 3-hour rule out protocol correctly ruled out 99.9% (95% CI, 99.1%-100%), 99.5% (95% CI, 98.3%-99.9%), 100% (95% CI, 98.1%-100%), and 100% (95% CI, 98.2%-100%) of early presenters (<6 h from chest pain onset). Using the 3 sensitive cTn assays, the 0-hour rule out protocol correctly ruled out 99.6% (95% CI, 98.6%-99.9%), 99.0% (95% CI, 96.9%-99.7%), and 99.1% (95% CI, 97.2%-99.8%) of late presenters; and the 3-hour rule out protocol correctly ruled out 99.4% (95% CI, 98.3%-99.8%), 99.2% (95% CI, 97.3%-99.8%), and 99.0% (95% CI, 97.2%-99.7%) of early presenters. Overall, the 0 h/3 h rule out protocol assigned 40% to 60% of patients to rule out. None of the patients assigned rule out died during 3-months follow-up.Conclusions: The 0 h/3 h rule out protocol seems to allow the accurate rule out of AMI using both high-sensitivity and sensitive cTn measurements in conjunction with clinical assessment. Additional studies are warranted for external validation. [ABSTRACT FROM AUTHOR]

Background: We sought to evaluate the hospital and midterm results of different surgical revascularization techniques in pediatric patients within the European Congenital Heart Surgeons Association. Methods: From 1973 to 2011, 80 patients from 13 European Congenital Heart Surgeons Association centers underwent 65 pediatric coronary artery bypass grafting (PCABG) and 27 other coronary artery procedures (OCAP; 12 patients had combined PCABG and other coronary artery procedures). Excluded were patients with Kawasaki disease. Median age at the time of coronary procedure was 2.3 years (range, 2 days to 16.9 years); 33 patients (41.2%) were younger then 12 months. An emergency procedure was necessary in 34 patients (42.5%). Results: Twelve patients (15%) died in the hospital; age at surgery (p = 0.02) and the need for an emergent procedure (p = 0.0004) were related to hospital mortality. Median follow-up time was 7.6 years (range, 0.9 to 23 years). There were 3 late cardiac deaths, all after a median time of 4 years (range, 9 months to 8.8 years) after PCABG. Fourteen patients (20.5%) presented with symptoms, including congestive heart failure (n = 10) and angina (n = 4), that were significantly associated with a low ejection fraction (p < 0.001) and the presence of moderate or severe mitral valve regurgitation (p = 0.0003). Six patients underwent a reintervention for impaired myocardial perfusion; all of them had a stenotic or atretic PCABG (p = 0.001), and the majority were symptomatic (5 of 6 patients; 83.3%; p = 0.001). Conclusions: Both PCABG and other coronary artery procedures are suitable surgical options in pediatric patients with impaired myocardial perfusion, which increases operative and midterm survival. Such population of patients needs to be followed for life to prevent and treat any possible cause of further myocardial ischemia. [Copyright &y& Elsevier]

Abstract: We studied the susceptibility of human embryonic stem cells and derived contractile embryoid bodies from WAO9, HUES-5 and HUES-16 cell lines to Coxsackievirus B infection. After validating stem cell-like properties and cardiac phenotype, Coxsackievirus B receptors CAR and DAF, as well as type I interferon receptors were detected in all cell lines and differentiation stages studied. Real-time PCR analysis showed that CAR mRNA levels were 3.4-fold higher in undifferentiated cells, while DAF transcript levels were 2.78-fold more abundant in differentiated cultures (P <0.05). All cell lines were susceptible to Coxsackievirus serotypes B1-5 infection as shown by RT-PCR detection of viral RNA, immunofluorescence detection of viral protein and infectivity titration of cell culture supernatants resulting in cell death. Supernatants infectivity titers 24-48h post-infection ranged from 105-106 plaque forming units (PFU)/ml, the highest titers were detected in undifferentiated cells. Cell viability detected by a colorimetric assay, showed inverse correlation with infectivity titers of cell culture supernatants. Treatment with 100 U of interferon Iβ significantly reduced viral replication and associated cell death during a 24–48 h observation period, as detected by reduced infectivity titers in the supernatants and increased cell viability by a colorimetric assay, respectively. We propose human embryonic stem cell and derived contractile embryoid bodies as a valid model to study cardiac Coxsackievirus B infection. [ABSTRACT FROM AUTHOR]

Summary: Objectives: The study of a predicted outer membrane leptospiral protein encoded by the gene LIC12690 in mediating the adhesion process. Methods: The gene was cloned and expressed in Escherichia coli BL21 (SI) strain by using the expression vector pAE. The recombinant protein tagged with N-terminal hexahistidine was purified by metal-charged chromatography and used to assess its ability to activate human umbilical vein endothelial cells (HUVECs). Results: The recombinant leptospiral protein of 95kDa, named Lp95, activated E-selectin in a dose-dependent fashion but not the intercellular adhesion molecule 1 (ICAM-1). In addition, we show that pathogenic and non-pathogenic Leptospira are both capable to stimulate endothelium E-selectin and ICAM-1, but the pathogenic L. interrogans serovar Copenhageni strain promotes a statistically significant higher activation than the non-pathogenic L. biflexa serovar Patoc (P < 0.01). The Lp95 was identified in vivo in the renal tubules of animal during experimental infection with L. interrogans. The whole Lp95 as well as its fragments, the C-terminal containing the domain of unknown function (DUF), the N-terminal and the central overlap regions bind laminin and fibronectin ECM molecules, being the binding stronger with the DUF containing fragment. Conclusion: This is the first leptospiral protein capable to mediate the adhesion to ECM components and the activation of HUVECS, thus suggesting its participation in the pathogenesis of Leptospira. [Copyright &y& Elsevier]

Background: Cardiovascular abnormalities and small vascular size may preclude transvenous pacing and necessitate epicardial lead implantation. This study evaluates the performance of steroid-eluting, bipolar epicardial pacing leads. Methods: We prospectively enrolled 114 children with 239 atrial and ventricular bipolar epicardial leads (Medtronic CapSure 10366 or 4968, Minneapolis, MN), followed up to 12.2 years (median, 3.2). Lead data were obtained at implant and at semi-annual visits. Analysis was done for left or right atrial and ventricular leads. Results: Median atrial and ventricular pacing thresholds remained below 1.2 V at 0.5 ms. Thresholds did not differ between pacing sites: left atrial, 0.82V at 0.5 ms; right atrial, 0.74 V at 0.5 ms (p = 0.85); and left ventricular, 0.96V at 0.5 ms; right ventricular, 0.94 V at 0.5 ms (p = 0.65). Sensing demonstrated no difference for atrial leads, at left atrial, 3.4 mV; and right atrial, 2.9 mV (p = 0.12), but there was superiority of left over right ventricular leads (11.2 vs 7.7 mV, p = 0.002). During follow-up, the 239 atrial and ventricular leads experienced 19 (8%) lead failures. Lead survival at 2 and 5 years was 99% and 94% for atrial leads and 96% and 85% for ventricular leads, respectively. Conclusions: Bipolar steroid-eluting epicardial leads demonstrate excellent sensing characteristics and persistent low median pacing thresholds below 1.2 V at 0.5 ms in children during up to 12 years follow-up. Considering growing and active patients with most having congenital heart disease, the lead survival of 85% to 94% at 5 years is favorable. Subanalysis shows superior sensing for left ventricular leads. Bipolar steroid-eluting leads provide an alternative approach for permanent pacing and may also be considered for left atrial and ventricular pacing, resynchronization, or defibrillator therapy. [Copyright &y& Elsevier]

BACKGROUND: The hospital readmission rate has been proposed as an important outcome indicator computable from routine statistics. However, most commonly used measures raise conceptual issues. OBJECTIVES: We sought to evaluate the usefulness of the computerized algorithm for identifying avoidable readmissions on the basis of minimum bias, criterion validity, and measurement precision. RESEARCH DESIGN AND SUBJECTS: A total of 131,809 hospitalizations of patients discharged alive from 49 hospitals were used to compare the predictive performance of risk adjustment methods. A subset of a random sample of 570 medical records of discharge/readmission pairs in 12 hospitals were reviewed to estimate the predictive value of the screening of potentially avoidable readmissions. MEASURES: Potentially avoidable readmissions, defined as readmissions related to a condition of the previous hospitalization and not expected as part of a program of care and occurring within 30 days after the previous discharge, were identified by a computerized algorithm. Unavoidable readmissions were considered as censored events. RESULTS: A total of 5.2% of hospitalizations were followed by a potentially avoidable readmission, 17% of them in a different hospital. The predictive value of the screen was 78%; 27% of screened readmissions were judged clearly avoidable. The correlation between the hospital rate of clearly avoidable readmission and all readmissions rate, potentially avoidable readmissions rate or the ratio of observed to expected readmissions were respectively 0.42, 0.56 and 0.66. Adjustment models using clinical information performed better. CONCLUSION: Adjusted rates of potentially avoidable readmissions are scientifically sound enough to warrant their inclusion in hospital quality surveillance. [ABSTRACT FROM AUTHOR]

Objective: Systemic inflammatory response syndrome and infectious complications are major causes of morbidity and mortality after cardiopulmonary bypass. Recent work in adult patients suggests that the balance between proinflammatory and anti-inflammatory mediators is important. We hypothesized that the expression of different function-related receptors on circulating monocytes might reflect the net response of the inflammatory reaction. Methods: We performed a prospective and observational study in a tertiary pediatric cardiac center in a population of children (n = 40) undergoing elective cardiac surgery. Expression of receptors on the surface of monocytes was assessed before, during, and after surgical intervention. Results: Early monocyte activation was demonstrated by changes of the expression of the chemokine receptor CCR2, which was inversely correlated with plasma levels of monocyte chemotactic protein 1 (rho = −0.54, P = .002). High levels of monocyte chemotactic protein 1 were found in children with high expression of the adhesion receptor CD11b/CD18 on circulating monocytes. The intensity of human leukocyte antigen DR expression rapidly decreased in all children after the onset of cardiopulmonary bypass (P < .001). Low human leukocyte antigen DR expression was correlated with increased plasma levels of interleukin 10 postoperatively. Children who had signs of bacterial pneumonia postoperatively had lower levels of human leukocyte antigen DR expression before surgical intervention (relative risk, 13.3; P = .007). Conclusions: The expression of monocyte function-related receptors is altered after cardiac surgery. Early activation of monocytes by monocyte chemotactic protein 1 possibly released from the heart is followed by an anti-inflammatory response with suppression of monocyte human leukocyte antigen DR expression. The increased risk of bacterial infection after pediatric cardiac surgery can be anticipated by surveillance of monocyte function before surgical intervention. [Copyright &y& Elsevier]

Unlabelled: We aimed to prospectively derive and validate a novel 0-/1-hour algorithm using high-sensitivity cardiac troponin I (hs-cTnI) for the early "rule-out" and "rule-in" of acute myocardial infarction (AMI).Methods: In a prospective multicenter diagnostic study, we enrolled 1,500 patients presenting with suspected AMI to the emergency department. The final diagnosis was centrally adjudicated by 2 independent cardiologists blinded to hs-cTnI concentrations. The hs-cTnI (Siemens Vista) 0-/1-hour algorithm incorporated measurements performed at baseline and absolute changes within 1 hour, was derived in the first 750 patients (derivation cohort), and then validated in the second 750 (validation cohort).Results: Overall, AMI was the final diagnosis in 16% of patients. Applying the hs-cTnI 0-/1-hour algorithm developed in the derivation cohort to the validation cohort, 57% of patients could be classified as "rule-out"; 10%, as "rule-in"; and 33%, as "observe." In the validation cohort, the sensitivity and the negative predictive value for AMI in the "rule-out" zone were 100% (95% CI 96%-100%) and 100% (95% CI 99%-100%), respectively. The specificity and the positive predictive value (PPV) for AMI in the "rule-in" zone were 96% (95% CI 94%-97%) and 70% (95% CI 60%-79%), respectively. Negative predictive value and positive predictive value of the 0-/1-hour algorithm were higher compared to the standard of care combining hs-cTnI with the electrocardiogram (both P < .001).Conclusion: The hs-cTnI 0-/1-hour algorithm performs very well for early rule-out as well as rule-in of AMI. The clinical implications are that used in conjunction with all other clinical information, the 0-/1-hour algorithm will be a safe and effective approach to substantially reduce time to diagnosis. [ABSTRACT FROM AUTHOR]

Most personnel neutron dosimeters and field monitors suffer from an energy dependence. The knowledge of the energy distribution of the measured neutron field is necessary to correct the response of the detectors. However, the response of the detectors can be significantly improved when only a simple idea of the spectrum hardness is available.This paper describes a way of characterizing the neutron spectrum hardness in a large variety of neutron fields (with energies extending from thermal to 100 MeV) by using the various indications of different types of passive neutron detectors. These indications allow the choice of the appropriate factors established by calibration measurements or taken from the literature to correct the energy dependent response of personnel neutron dosimeters and field monitors. [ABSTRACT FROM AUTHOR]