Nicht-manuelle Immobilisierung von biologischen Erkennungselementen durch pH-induzierte Deposition von Polymerfilmen als Basis für die reproduzierbare Herstellung amperometrischer Biosensoren

Die reproduzierbare, parallele und nicht-manuelle Fixierung von molekularen Erkennungselementen auf Oberflächen hat eine erhebliche Bedeutung für die Entwicklung von spezifischen Sensoren für Anwendungen im Bereich der Biotechnologie, der klinischen Analytik, der medizinischen Diagnostik sowie in der kombinatorischen Chemie und dem Hochdurchsatzscreening. Insbesondere bei der Miniaturisierung von Biosensoren sowie der Herstellung höher integrierter Sensor-Aktuator-Systeme besteht dabei die Notwendigkeit für eine lokale Abscheidungstechnik mit hoher Auflösung bei gleichzeitig geringem Verbrauch an biologischen Erkennungskomponenten. Eine Methode, die diese Anforderungen erfüllen kann, ist die elektrochemisch induzierte Abscheidung von Polymeren in Gegenwart unterschiedlicher Erkennungselemente. Dabei erfolgt bei den herkömmlich verwendeten Polymerabscheidungen[1] die Kettenwachstumsreaktion durch Oxidation des entsprechenden Monomers über intermediäre radikalische Zwischenstufen in der Diffusionsschicht vor der Elektrode. Aufgrund des Radikalmechanismus sind solche Reaktionen sensitiv gegenüber der Anwesenheit von molekularem Sauerstoff und nukleophilen Reagenzien, so daß die Konzentration von Proteinen (z.B. Enzymen) in der Abscheidungslösung wegen der nukleophilen Seitenketten gering gehalten werden muß. Demgegenüber erfolgt die Bildung des Polymerfilms bei der von uns auf Basis eines industriell gebräuchlichen Verfahrens für den Korrosionsschutz entwickelten Methode, durch eine elektrochemisch oder photochemisch induzierte lokale Änderung des pH-Wertes, welche die Löslichkeit von emulgierten Polymeren verändert und somit zu dessen Koagulation auf der Elektrodenoberfläche führt. Die elektrochemische Abscheidung kann dabei je nach verwendetem Polymer entweder an der Anode oder der Kathode erfolgen

Treatment Satisfaction and Convenience for Patients With Atrial Fibrillation on Edoxaban or Vitamin K Antagonists After Transcatheter Aortic Valve Replacement:A Post Hoc Analysis from the ENVISAGE-TAVI AF Trial

ENVISAGE-TAVI AF (Edoxaban versus Standard of Care and Their Effects on Clinical Outcomes in Patients Having Undergone Transcatheter Aortic Valve Implantation–Atrial Fibrillation; NCT02943785) was a prospective, randomized, open-label trial comparing non–vitamin K oral anticoagulant (NOAC) edoxaban with vitamin K antagonists (VKAs) in patients with atrial fibrillation after successful transcatheter aortic valve replacement (TAVR). The effect of edoxaban- or VKA-based therapy on patient-reported outcomes remains unknown, as most studies focus on efficacy and safety. Pre-TAVR patient-reported expectations and post-TAVR Treatment Satisfaction and Convenience with edoxaban or VKA treatment (at months 3 and 12) were analyzed using the Perception of Anticoagulation Treatment Questionnaire (PACT-Q). This analysis included randomized and dosed patients with an evaluable PACT-Q1 assessment at baseline and ≥1 postbaseline assessment (PACT-Q2). Subanalyses included patients stratified by pre-TAVR anticoagulant (NOAC, VKA, no NOAC/VKA). Edoxaban- (n = 585) and VKA-treated (n = 522) patients had similar baseline characteristics and treatment expectations. Pre-TAVR anticoagulant use did not affect treatment expectations. After TAVR, edoxaban-treated patients had significantly higher Treatment Satisfaction and Convenience scores compared with VKA-treated patients at all time points (p &lt;0.001 for all). Among edoxaban-treated patients, those who received VKAs pre-TAVR were significantly more satisfied with treatment than those who received NOACs (p &lt;0.001) or no NOACs/VKAs (p = 0.003); however, there was no significant difference in the perception of convenience (p = 0.927 and p = 0.092, respectively). Conversely, among VKA-treated patients, the type of anticoagulant used pre-TAVR did not affect Treatment Satisfaction or Convenience scores post-TAVR. In conclusion, patients with atrial fibrillation who received edoxaban post-TAVR reported significantly higher Treatment Satisfaction and Convenience scores compared with those who received VKAs, resulting in a clinically meaningful difference between treatment groups.</p

Outcomes after TAVI in patients with atrial fibrillation and a history of recent PCI:Results from the ENVISAGE-TAVI AF trial

Background: Patients with atrial fibrillation (AF) and a recent (≤ 90 days) percutaneous coronary intervention (PCI) undergoing transcatheter aortic valve implantation (TAVI) are at high bleeding risk due to the addition of oral antiplatelet (OAP) agents on top of oral anticoagulants. Data on outcomes of these patients are needed to optimize antithrombotic treatment. Methods: This analysis compared annualized clinical event rates in patients with and without a recent PCI enrolled in ENVISAGE-TAVI AF, a prospective, randomized, open-label, adjudicator-masked trial comparing edoxaban and vitamin K antagonists in AF patients after TAVI. The primary efficacy and safety outcomes were net adverse clinical events (NACE) and major bleeding. Results: Overall, 132 (94.3%) patients with a recent PCI (n = 140) received OAP after TAVI, compared with 692 (55.9%) patients without a recent PCI (n = 1237). Among patients with a recent PCI on OAP agents, use of dual antiplatelet therapy decreased to 5.5%, and use of single antiplatelet therapy (SAPT) increased to 78.0% over 3 months post-randomization. Conversely, use of SAPT predominated at all time points in patients without a recent PCI history. There were no significant differences in the incidence of NACE or other outcomes assessed, except for major bleeding events, which were more frequent in patients with vs without a recent PCI history (hazard ratio [95% confidence interval]: 2.17 [1.27, 3.73]; P = 0.005). Conclusions: Patients with AF undergoing TAVI with a recent PCI have a similar risk of ischemic events and mortality, but an increased risk of major bleeding compared with patients without a recent PCI. Graphical abstract: [Figure not available: see fulltext.].</p

Circulating brain‐derived neurotrophic factor concentrations and the risk of cardiovascular disease in the community

BACKGROUND: Brain‐derived neurotrophic factor (BDNF) is a pleiotropic peptide involved in maintaining endothelial integrity. It is unknown if circulating BDNF levels are associated with risk of cardiovascular disease (CVD). METHODS AND RESULTS: We prospectively investigated the association of circulating BDNF levels with cardiovascular events and mortality in 3687 participants (mean age 65 years, 2068 women) from the Framingham Heart Study (FHS). Using a common nonsynonomous single nucleotide polymorphism (SNP) in the BDNF gene (rs6265), we then performed a Mendelian randomization experiment in the CARDIoGRAM (Coronary ARtery DIsease Genome‐Wide Replication And Meta‐Analysis) consortium (>22 000 coronary artery disease [CAD] cases, >60 000 controls) to investigate whether SNP rs6265 was associated with CAD in CARDIoGRAM and, if so, whether the effect estimate differed from that predicted based on FHS data. On follow‐up (median 8.9 years), 467 individuals (261 women) in FHS experienced a CVD event, and 835 (430 women) died. In multivariable‐adjusted Cox regression, serum BDNF was associated inversely with CVD risk (hazard ratio [HR] per 1‐SD increase 0.88, 95% CI 0.80 to 0.97, P=0.01) and with mortality (HR 0.87, 95% CI 0.80 to 0.93, P=0.0002). SNP rs6265 was associated with BDNF concentrations (0.772 ng/mL increase per minor allele copy) in FHS. In CARDIoGRAM, SNP rs6265 was associated with CAD (odds ratio 0.957, 95% CI 0.923 to 0.992), a magnitude consistent with the predicted effect (HR per minor allele copy 0.99, 95% CI 0.98 to 1.0; P=0.06 for difference between predicted and observed effect). CONCLUSION: Higher serum BDNF is associated with a decreased risk of CVD and mortality. Mendelian randomization suggests a causal protective role of BDNF in the pathogenesis of CVD

Risk Factors of Ischemic Stroke in Patients With Atrial Fibrillation After Transcatheter Aortic Valve Implantation from the Randomized ENVISAGE-TAVI AF Trial

In patients with prevalent or incident atrial fibrillation (AF) after successful transcatheter aortic valve implantation (TAVI) enrolled in the EdoxabaN Versus standard of care and theIr effectS on clinical outcomes in pAtients havinG undergonE Transcatheter Aortic Valve Implantation - in Atrial Fibrillation (ENVISAGE-TAVI AF) trial, the incidence of ischemic stroke (IS) and any stroke was numerically less in the edoxaban group than in the vitamin K antagonist (VKA) group. The present study aimed to identify risk factors associated with IS in an on-treatment subanalysis in patients from ENVISAGE-TAVI AF who received ≥1 dose of edoxaban or VKA. Baseline patient characteristics were compared in patients with and those without IS. Numerical variables were compared using a 1-way analysis of variance; categorical variables were compared using Fisher's exact test. Stepwise Cox regression determined patient characteristics associated with the first IS event. Of 1,377 patients, 41 (3.0%) experienced an IS, and 1,336 (97.0%) did not; baseline demographics and clinical characteristics were well balanced between groups. Most ISs occurred within 180 days of TAVI for edoxaban (57.9%) and VKA (68.2%). The rate of IS was 2.0/100 person-years for edoxaban versus 2.7/100 person-years for VKA. Independently associated with IS were history of systemic embolic events (hazard ratio 2.96, 95% confidence interval 1.26 to 7.00, p = 0.01) and pre-TAVI use of VKAs (hazard ratio 2.17, 95% confidence interval 1.12 to 4.20, p = 0.02). In conclusion, although the overall incidence of IS was small for patients with AF on edoxaban or VKA after successful TAVI, patients with a history of systemic embolic events or pre-TAVI use of VKAs may be at greater risk of IS after TAVI.</p

Quantitative fluid overload in severe aortic stenosis refines cardiac damage and associates with worse outcomes

Aims: Cardiac decompensation in aortic stenosis (AS) involves extra-valvular cardiac damage and progressive fluid overload (FO). FO can be objectively quantified using bioimpedance spectroscopy. We aimed to assess the prognostic value of FO beyond established damage markers to guide risk stratification. Methods and results: Consecutive patients with severe AS scheduled for transcatheter aortic valve implantation (TAVI) underwent prospective risk assessment with bioimpedance spectroscopy (BIS) and echocardiography. FO by BIS was defined as ≥1.0 L (0.0 L = euvolaemia). The extent of cardiac damage was assessed by echocardiography according to an established staging classification. Right-sided cardiac damage (rCD) was defined as pulmonary vasculature/tricuspid/right ventricular damage. Hospitalization for heart failure (HHF) and/or death served as primary endpoint. In total, 880 patients (81 ± 7 years, 47% female) undergoing TAVI were included and 360 (41%) had FO. Clinical examination in patients with FO was unremarkable for congestion signs in >50%. A quarter had FO but no rCD (FO+/rCD−). FO+/rCD+ had the highest damage markers, including N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. After 2.4 ± 1.0 years of follow-up, 236 patients (27%) had reached the primary endpoint (29 HHF, 194 deaths, 13 both). Quantitatively, every 1.0 L increase in bioimpedance was associated with a 13% increase in event hazard (adjusted hazard ratio 1.13, 95% confidence interval 1.06–1.22, p < 0.001). FO provided incremental prognostic value to traditional risk markers (NT-proBNP, EuroSCORE II, damage on echocardiography). Stratification according to FO and rCD yielded worse outcomes for FO+/rCD+ and FO+/rCD−, but not FO−/rCD+, compared to FO−/rCD−. Conclusion: Quantitative FO in patients with severe AS improves risk prediction of worse post-interventional outcomes compared to traditional risk assessment

Comprehensive exploration of the effects of miRNA SNPs on monocyte gene expression

We aimed to assess whether pri-miRNA SNPs (miSNPs) could influence monocyte gene expression, either through marginal association or by interacting with polymorphisms located in 3'UTR regions (3utrSNPs). We then conducted a genome-wide search for marginal miSNPs effects and pairwise miSNPs × 3utrSNPs interactions in a sample of 1,467 individuals for which genome-wide monocyte expression and genotype data were available. Statistical associations that survived multiple testing correction were tested for replication in an independent sample of 758 individuals with both monocyte gene expression and genotype data. In both studies, the hsa-mir-1279 rs1463335 was found to modulate in cis the expression of LYZ and in trans the expression of CNTN6, CTRC, COPZ2, KRT9, LRRFIP1, NOD1, PCDHA6, ST5 and TRAF3IP2 genes, supporting the role of hsa-mir-1279 as a regulator of several genes in monocytes. In addition, we identified two robust miSNPs × 3utrSNPs interactions, one involving HLA-DPB1 rs1042448 and hsa-mir-219-1 rs107822, the second the H1F0 rs1894644 and hsa-mir-659 rs5750504, modulating the expression of the associated genes. As some of the aforementioned genes have previously been reported to reside at disease-associated loci, our findings provide novel arguments supporting the hypothesis that the genetic variability of miRNAs could also contribute to the susceptibility to human diseases