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1.
Front Cardiovasc Med ; 11: 1384736, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39049954

RESUMO

Background: Data on the use of the wearable cardioverter defibrillator in patients suffering from inherited and congenital heart disease are limited. Consequently, evidence for guideline recommendations in this patient population is lacking. Methods: In total 1,675 patients were included in a multicenter registry of eight European centers. In the present cohort, we included 18 patients suffering from congenital and inherited heart disease. Results: Nine patients (50%) were male with a mean age of 41.3 ± 16.4 years. Four patients suffered from hypertrophic cardiomyopathy (HCM), four patients suffered from non-compaction cardiomyopathy (NCCM), two patients were diagnosed with arrhythmogenic right ventricular cardiomyopathy (ARVC) and one patient suffered from muscular dystrophy of the limb-girdle type with cardiac involvement, secondary cardiomyopathy. Three patients presented with Brugada syndrome (BrS). One patient suffered from long-QT syndrome type 1 (LQTS1). Furthermore, two patients had congenital heart defects and one patient suffered from cardiac sarcoidosis (CS). There were no appropriate/inappropriate shocks with the WCD in this cohort. One patient had recurrent self-limiting sustained ventricular tachycardia during the wear time, but actively inhibited a shock and was hospitalized. The compliance rate in this cohort was 77.8% with a mean wear time of 45.3 ± 26.9 days with a mean follow-up time of 570 ± 734 days. 55.6% (10/18) of the patients received an ICD after WCD wear time. Conclusions: This retrospective study of patients with inherited and congenital heart disease shows that WCD use is not beneficial in the majority of patients with inherited and congenital heart disease.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38985244

RESUMO

BACKGROUND AND AIMS: Wearable cardioverter defibrillator (WCD) can protect patients from sudden cardiac death due to ventricular tachyarrhythmias and serve as a bridge to decision of definite defibrillator implantation. The aim of this analysis from an international, multicenter WCD registry was to identify predictors of sustained ventricular tachycardia (VT) and/or ventricular fibrillation (VF) in this population. METHODS: One thousand six hundred seventy-five patients with WCD were included in a multicenter registry from 9 European centers, with a median follow-up of 440 days (IQR 120-893). The primary study end point was the occurrence of sustained VT/VF. RESULTS: Sustained VT was detected by WCD in 5.4% and VF in 0.9% of all patients. Of the 30.3% of patients receiving ICD implantation during follow-up, sustained VT was recorded in 9.3% and VF in 2.6%. Non-ischemic cardiomyopathy (HR 0.5, p < 0.001), and medication with angiotensin-converting enzyme inhibitors (HR 0.7, p = 0.027) and aldosterone antagonists (HR 0.7, p = 0.005) were associated with a significantly lower risk of VT/VF. CONCLUSIONS: Patients who received WCD due to a transient increased risk of sudden cardiac death have a comparatively lower risk of VT/VF in the presence of non-ischemic cardiomyopathy. Of note, optimal medical treatment for heart failure not only results in an improvement in left ventricular ejection fraction but also in a reduction in the risk for VT/VF.

3.
Cardiovasc Revasc Med ; 60: 35-40, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37838620

RESUMO

BACKGROUND: The Carillon® Mitral Contour System® has been studied in 4 prospective controlled studies in the treatment of functional mitral regurgitation (FMR) where it has been found to reduce mitral regurgitation, reduce left ventricular and atrial volumes, and be associated with improvements in clinical parameters. AIMS: The CINCH post-market registry is designed to evaluate immediate, mid-term and long-term outcomes from a post-approval study of the Carillon® device evaluated in real-world practice. METHODS: The CINCH post-market registry is a single-arm study of percutaneous mitral annuloplasty with the Carillon device in patients with functional (secondary) mitral regurgitation and symptomatic congestive heart failure when utilized in real-world conditions. Patient selection, echocardiographic hemodynamic measurements, and patient follow-up requirements were performed per standard of care at each institution. RESULTS: A total of 101 patients treated with the Carillon device at 13 sites in Germany were enrolled in the CINCH registry. The mean age was 75 ± 9 years, 57 % were male, and patient presentation included primarily NYHA class III (69 %) with MR grade 3 (68 %). Over 5 years of follow-up, all-cause mortality was 40.1 %, the incidence of HFH was 53.9 %, and the composite outcome of HFH or death was 66.4 %. At each follow-up interval through 5 years, statistically significant reductions in NYHA class (p < 0.05) and MR grade (p < 0.01) were reported. CONCLUSIONS: In this "real world" registry of the Carillon Mitral Contour System, procedural safety and medium-term follow-up outcomes is similar to the outcomes seen in the prospective, controlled clinical trials, despite being used in populations of patients that extend outside of those studied in the trials. The use of this therapy in patients with atrial functional mitral regurgitation, and heart failure with preserved ejection fraction, was notable, since these types of patients were excluded from the prospective, controlled trials. This supports possible additional patient populations who might benefit from this type of mechanical therapy. The safety profile of this therapy in this registry and in the earlier trials may support a potential role in earlier forms of secondary mitral regurgitation.


Assuntos
Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca , Anuloplastia da Valva Mitral , Insuficiência da Valva Mitral , Humanos , Masculino , Idoso , Idoso de 80 Anos ou mais , Feminino , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Estudos Prospectivos , Ecocardiografia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Anuloplastia da Valva Mitral/efeitos adversos , Sistema de Registros , Resultado do Tratamento
4.
J Am Heart Assoc ; 12(18): e030615, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37681569

RESUMO

Background Data on the use of the wearable cardioverter-defibrillator (WCD) among patients with myocarditis remain sparse. Consequently, evidence for guideline recommendations in this patient population is lacking. Methods and Results In total, 1596 consecutive patients were included in a multicenter registry from 8 European centers, with 124 patients (8%) having received the WCD due to myocarditis and reduced left ventricular ejection fraction or prior ventricular tachyarrhythmia. The mean age was 51.6±16.3 years, with 74% being male. Patients were discharged after index hospitalization on heart failure medication: Angiotensin-converting enzyme inhibitors (62.5%), angiotensin-receptor-neprilysin inhibitor (22.9%), aldosterone-antagonists (51%), or beta blockers (91.4%). The initial median left ventricular ejection fraction was 30% (22%-45%) and increased to 48% (39%-55%) over long-term follow-up (P<0.001). The median BNP (brain natriuretic peptide) level at baseline was 1702 pg/mL (565-3748) and decreased to 188 pg/mL (26-348) over long-term follow-up (P=0.022). The mean wear time was 79.7±52.1 days and 21.0±4.9 hours per day. Arrhythmic event rates documented by the WCD were 9.7% for nonsustained ventricular tachycardia, 6.5% for sustained ventricular tachycardia, and 0% for ventricular fibrillation. Subsequently, 2.4% of patients experienced an appropriate WCD shock. The rate of inappropriate WCD shocks was 0.8%. All 3 patients with appropriate WCD shock had experienced ventricular tachycardia/ventricular fibrillation before WCD prescription, with only 1 patient showing a left ventricular ejection fraction <35%. Conclusions Patients with myocarditis and risk for occurrence of ventricular tachyarrhythmia may benefit from WCD use. Prior ventricular arrhythmia might appear as a better risk predictor than a reduced left ventricular ejection fraction <35% in this population.


Assuntos
Miocardite , Taquicardia Ventricular , Dispositivos Eletrônicos Vestíveis , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Volume Sistólico , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/terapia , Função Ventricular Esquerda , Miocardite/complicações , Miocardite/terapia , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/terapia , Desfibriladores
5.
ACS Appl Electron Mater ; 5(6): 3261-3267, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37396054

RESUMO

Owing to its high electrical conductivity, low density, and flexibility, graphene has great potential for use as a building block in a wide range of applications from nanoelectronics to biosensing and high-frequency devices. For many device applications, it is required to deposit dielectric materials on graphene at high temperatures and in ambient oxygen. This has been proven to be highly challenging because these conditions cause significant degradation in graphene. In this work, we investigate the degradation of graphene at elevated temperatures in an oxygen atmosphere and possible protection mechanisms to enable the growth of oxide thin films on graphene at higher temperatures. We show that coating graphene with self-assembled monolayers of hexamethyldisilazane (HMDS) prior to a high-temperature deposition can significantly reduce the damage induced. Furthermore, a graphene sample treated with HMDS displayed a weaker doping effect due to weak interaction with oxygen species than bare graphene, and a much slower rate of electrical resistance degradation was exhibited during annealing. Thus, it is a promising approach that could enable the deposition of metal oxide materials on graphene at high temperatures without significant degradation in graphene quality, which is critical for a wide range of applications.

6.
ACS Nano ; 17(15): 14619-14631, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37470391

RESUMO

Biosensors based on graphene field effect transistors (GFETs) have the potential to enable the development of point-of-care diagnostic tools for early stage disease detection. However, issues with reproducibility and manufacturing yields of graphene sensors, but also with Debye screening and unwanted detection of nonspecific species, have prevented the wider clinical use of graphene technology. Here, we demonstrate that our wafer-scalable GFETs array platform enables meaningful clinical results. As a case study of high clinical relevance, we demonstrate an accurate and robust portable GFET array biosensor platform for the detection of pancreatic ductal adenocarcinoma (PDAC) in patients' plasma through specific exosomes (GPC-1 expression) within 45 min. In order to facilitate reproducible detection in blood plasma, we optimized the analytical performance of GFET biosensors via the application of an internal control channel and the development of an optimized test protocol. Based on samples from 18 PDAC patients and 8 healthy controls, the GFET biosensor arrays could accurately discriminate between the two groups while being able to detect early cancer stages including stages 1 and 2. Furthermore, we confirmed the higher expression of GPC-1 and found that the concentration in PDAC plasma was on average more than 1 order of magnitude higher than in healthy samples. We found that these characteristics of GPC-1 cancerous exosomes are responsible for an increase in the number of target exosomes on the surface of graphene, leading to an improved signal response of the GFET biosensors. This GFET biosensor platform holds great promise for the development of an accurate tool for the rapid diagnosis of pancreatic cancer.


Assuntos
Técnicas Biossensoriais , Carcinoma Ductal Pancreático , Exossomos , Grafite , Neoplasias Pancreáticas , Humanos , Reprodutibilidade dos Testes , Transistores Eletrônicos , Neoplasias Pancreáticas/diagnóstico , Técnicas Biossensoriais/métodos , Carcinoma Ductal Pancreático/diagnóstico , Neoplasias Pancreáticas
8.
Eur J Clin Invest ; 53(7): e13977, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36852491

RESUMO

BACKGROUND: Wearable cardioverter defibrillators (WCD) are used as a 'bridging' technology in patients, who are temporarily at high risk for sudden cardiac death (SCD). Several factors should be taken into consideration, for example patient selection, compliance and optimal drug treatment, when WCD is prescribed. We aimed to present real-world data from seven centres from Germany and Switzerland according to age differences regarding the outcome, prognosis, WCD data and compliance. MATERIALS AND METHODS: Between 04/2012 and 03/2021, 1105 patients were included in this registry. Outcome data according to age differences (old ≥45 years compared to young <45 years) were analysed. At young age, WCDs were more often prescribed due to congenital heart disease and myocarditis. On the other hand, ischaemic cardiomyopathy (ICM) was more present in older patients. Wear days of WCD were similar between both groups (p = .115). In addition, during the WCD use, documented arrhythmic life-threatening events were comparable [sustained ventricular tachycardia: 5.8% vs. 7.7%, ventricular fibrillation (VF) .5% vs. .6%] and consequently the rate of appropriate shocks was similar between both groups. Left ventricular ejection fraction improvement was documented over follow-up with a better improvement in younger patients as compared to older patients (77% vs. 63%, p = .002). In addition, at baseline, the rate of atrial fibrillation was significantly higher in the older age group (23% vs. 8%; p = .001). The rate of permanent cardiac implantable electronic device implantation (CiED) was lower in the younger group (25% vs. 36%, p = .05). The compliance rate defined as wearing WCD at least 20 h per day was significantly lower in young patients compared to old patients (68.9% vs. 80.9%, p < .001). During the follow-up, no significant difference regarding all-cause mortality or arrhythmic death was documented in both groups. A low compliance rate of wearing WCD is predicted by young patients and patients suffering from non-ischaemic cardiomyopathies. CONCLUSION: Although the compliance rate in different age groups is high, the average wear hours tended to be lower in young patients compared to older patients. The clinical events were similar in younger patients compared to older patients.


Assuntos
Fibrilação Atrial , Isquemia Miocárdica , Dispositivos Eletrônicos Vestíveis , Humanos , Idoso , Pessoa de Meia-Idade , Volume Sistólico , Função Ventricular Esquerda , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/etiologia , Isquemia Miocárdica/terapia , Isquemia Miocárdica/complicações , Sistema de Registros , Fibrilação Atrial/complicações , Desfibriladores/efeitos adversos , Estudos Retrospectivos
9.
Technol Health Care ; 31(2): 735-746, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36442163

RESUMO

BACKGROUND: Atrial fibrillation (AF) is associated with significant morbidity and is predicted by atrial high rate events. The early detection of AF is paramount to timely interventions to reduce the morbidity of AF. The DX ICD system combined with Home Monitoring® allows for continuous atrial rhythm monitoring without the need for a dedicated atrial lead. OBJECTIVE: To establish the reaction to and timing of reactions to the detection of atrial high rate episodes (AHRE). METHODS: A prospective cohort of DX ICD systems was followed up and the response to AHREs was collected and evaluated. RESULTS: A total of 234 patients were enrolled; an AHRE ⩾ 6 min was detected in 13.7% of patients (n= 32) within a mean follow-up duration of 16 months. A high rate of oral anticoagulation (OAC) prescription was seen with the detection of AHREs in patients with a not-low risk CHA2DS2-VASc score. There was a delay in this prescription highlighting the potential to improve the timeliness of patient care in this group of patients. CONCLUSIONS: The DX ICD system provides rapid and ongoing atrial rhythm monitoring such that physicians are rapidly aware of AHRE without the need for a dedicated atrial lead, but local protocols are needed to improve the response time of anti-coagulation prescription.


Assuntos
Fibrilação Atrial , Desfibriladores Implantáveis , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/terapia , Fibrilação Atrial/diagnóstico , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Fatores de Risco
10.
Sens Diagn ; 1(4): 719-730, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35923775

RESUMO

Graphene field-effect transistor (GFET) biosensors exhibit high sensitivity due to a large surface-to-volume ratio and the high sensitivity of the Fermi level to the presence of charged biomolecules near the surface. For most reported GFET biosensors, bulky external reference electrodes are used which prevent their full-scale chip integration and contribute to higher costs per test. In this study, GFET arrays with on-chip integrated liquid electrodes were employed for COVID-19 detection and functionalized with either antibody or aptamer to selectively bind the spike proteins of SARS-CoV-2. In the case of the aptamer-functionalized GFET (aptasensor, Apt-GFET), the limit-of-detection (LOD) achieved was about 103 particles per mL for virus-like particles (VLPs) in clinical transport medium, outperforming the Ab-GFET biosensor counterpart. In addition, the aptasensor achieved a LOD of 160 aM for COVID-19 neutralizing antibodies in serum. The sensors were found to be highly selective, fast (sample-to-result within minutes), and stable (low device-to-device signal variation; relative standard deviations below 0.5%). A home-built portable readout electronic unit was employed for simultaneous real-time measurements of 12 GFETs per chip. Our successful demonstration of a portable GFET biosensing platform has high potential for infectious disease detection and other health-care applications.

11.
J Cardiovasc Electrophysiol ; 33(11): 2243-2249, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35930623

RESUMO

AIMS: Treatment with the wearable cardioverter defibrillator (WCD) may protect against sudden cardiac death (SCD) as a bridging therapy until a cardioverter-defibrillator may be implanted. We analyzed in a multicenter setting a consecutive patient cohort wearing WCD to explore sex differences. METHODS AND RESULTS: We analyzed 708 consecutive patients, 579 (81.8%) from whom were males and 129 (18.2%) females (age, 60.5 ± 14 vs. 61.6 ± 17 years old; p = .44). While the rate of ischemic cardiomyopathy (ICM) as a cause of prescription of WCD was significantly higher in males as compared to females (42.7% vs. 26.4%; p = .001), females received it more frequently due to nonischemic cardiomyopathy (NICM) (55.8% vs. 42.7%); p = .009). The wear time of WCD was equivalent in both groups (21.1 ± 4.3 h/days in males vs. 21.5 ± 4.4 h/days in females; p = .27; and 62.6 ± 44.3 days in males vs. 56.5 ± 39 days in females; p = .15). Mortality was comparable in both groups at 2-year-follow-up (6.8% in males vs. 9.7% in females; p = .55). Appropriate WCD shocks and the incidence of ICD implantations were similar in both groups (2.4% in males vs. 3.9% in females; p = .07) (35.1% in males vs. 31.8% in females; p = .37), respectively. In age tertile analysis, compliance was observed more in 73-91 years old group as compared with 14-51 years old group (87.8% vs. 68.3%; p < .001). CONCLUSION: Compliance for wearing WCD was excellent regardless of sex. Furthermore, mortality and the incidence of ICD implantations were comparable in both sexes. Appropriate WCD shocks were similar in both sexes.


Assuntos
Cardiomiopatias , Desfibriladores Implantáveis , Dispositivos Eletrônicos Vestíveis , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto , Adolescente , Adulto Jovem , Caracteres Sexuais , Cardioversão Elétrica/efeitos adversos , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/etiologia , Cardiomiopatias/complicações , Desfibriladores , Desfibriladores Implantáveis/efeitos adversos
12.
Sci Rep ; 12(1): 3203, 2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35217697

RESUMO

Patients at high risk for sudden cardiac death (SCD) may benefit from wearable cardioverter defibrillators (WCD) by avoiding immediate implantable cardioverter defibrillator (ICD) implantation. Different factors play an important role including patient selection, compliance and optimal drug treatment. We aimed to present real world data from 4 centers from Germany and Switzerland. Between 04/2012 and 03/2019, 708 patients were included in this registry. Patients were followed up over a mean time of 28 ± 35.5 months. Outcome data including gender differences and different etiologies of cardiomyopathy were analyzed. Out of 708 patients (81.8% males, mean age 61.0 ± 14.6), 44.6% of patients had non-ischemic cardiomyopathy, 39.8% ischemic cardiomyopathy, 7.9% myocarditis, 5.4% prior need for ICD explantation and 2.1% channelopathy. The mean wear time of WCD was 21.2 ± 4.3 h per day. In 46% of patients, left ventricular ejection fraction (LVEF) was > 35% during follow-up. The younger the patient was, the higher the LVEF and the lower the wear hours per day were. The total shock rate during follow-up was 2.7%. Whereas an appropriate WCD shock was documented in 16 patients (2.2%), 3 patients received an inappropriate ICD shock (0.5%). During follow-up, implantation of a cardiac implantable electronic device was carried out in 34.5% of patients. When comparing German patients (n = 516) to Swiss patients (n = 192), Swiss patients presented with longer wear days (70.72 ± 49.47 days versus 58.06 ± 40.45 days; p = 0.001) and a higher ICD implantation rate compared to German patients (48.4% versus 29.3%; p = 0.001), although LVEF at follow-up was similar between both groups. Young age is a negative independent predictor for the compliance in this large registry. The most common indication for WCD was non-ischemic cardiomyopathy followed by ischemic cardiomyopathy. The compliance rate was generally high with a decrease of wear hours per day at younger age. Slight differences were found between Swiss and German patients, which might be related to differences in mentality for ICD implantation.


Assuntos
Cardiomiopatias , Desfibriladores Implantáveis , Isquemia Miocárdica , Dispositivos Eletrônicos Vestíveis , Idoso , Cardiomiopatias/complicações , Cardiomiopatias/terapia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores/efeitos adversos , Desfibriladores Implantáveis/efeitos adversos , Cardioversão Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Sistema de Registros , Volume Sistólico , Função Ventricular Esquerda , Dispositivos Eletrônicos Vestíveis/efeitos adversos
13.
ACS Sens ; 7(1): 253-262, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-34908400

RESUMO

Glial fibrillary acidic protein (GFAP) is a discriminative blood biomarker for many neurological diseases, such as traumatic brain injury. Detection of GFAP in buffer solutions using biosensors has been demonstrated, but accurate quantification of GFAP in patient samples has not been reported, yet in urgent need. Herein, we demonstrate a robust on-chip graphene field-effect transistor (GFET) biosensing method for sensitive and ultrafast detection of GFAP in patient plasma. Patients with moderate-severe traumatic brain injuries, defined by the Mayo classification, are recruited to provide plasma samples. The binding of target GFAP with the specific antibodies that are conjugated on a monolayer GFET device triggers the shift of its Dirac point, and this signal change is correlated with the GFAP concentration in the patient plasma. The limit of detection (LOD) values of 20 fg/mL (400 aM) in buffer solution and 231 fg/mL (4 fM) in patient plasma have been achieved using this approach. In parallel, for the first time, we compare our results to the state-of-the-art single-molecule array (Simoa) technology and the classic enzyme-linked immunosorbent assay (ELISA) for reference. The GFET biosensor shows competitive LOD to Simoa (1.18 pg/mL) and faster sample-to-result time (<15 min), and also it is cheaper and more user-friendly. In comparison to ELISA, GFET offers advantages of total detection time, detection sensitivity, and simplicity. This GFET biosensing platform holds high promise for the point-of-care diagnosis and monitoring of traumatic brain injury in GP surgeries and patient homes.


Assuntos
Técnicas Biossensoriais , Lesões Encefálicas Traumáticas , Grafite , Ensaio de Imunoadsorção Enzimática , Proteína Glial Fibrilar Ácida , Humanos
14.
ACS Omega ; 6(7): 4767-4775, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33644584

RESUMO

The performance of graphene devices is often limited by defects and impurities induced during device fabrication. Polymer residue left on the surface of graphene after photoresist processing can increase electron scattering and hinder electron transport. Furthermore, exposing graphene to plasma-based processing such as sputtering of metallization layers can increase the defect density in graphene and alter the device performance. Therefore, the preservation of the high-quality surface of graphene during thin-film deposition and device manufacturing is essential for many electronic applications. Here, we show that the use of self-assembled monolayers (SAMs) of hexamethyldisilazane (HMDS) as a buffer layer during the device fabrication of graphene can significantly reduce damage, improve the quality of graphene, and enhance device performance. The role of HMDS has been systematically investigated using surface analysis techniques and electrical measurements. The benefits of HMDS treatment include a significant reduction in defect density compared with as-treated graphene and more than a 2-fold reduction of contact resistance. This surface treatment is simple and offers a practical route for improving graphene device interfaces, which is important for the integration of graphene into functional devices such as electronics and sensor devices.

15.
ACS Appl Mater Interfaces ; 13(7): 7854-7864, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33560115

RESUMO

Graphene field-effect transistors (GFETs) are suitable building blocks for high-performance electrical biosensors, because graphene inherently exhibits a strong response to charged biomolecules on its surface. However, achieving ultralow limit-of-detection (LoD) is limited by sensor response time and screening effect. Herein, we demonstrate that the detection limit of GFET biosensors can be improved significantly by decorating the uncovered graphene sensor area with carbon dots (CDs). The developed CDs-GFET biosensors used for exosome detection exhibited higher sensitivity, faster response, and three orders of magnitude improvements in the LoD compared with nondecorated GFET biosensors. A LoD down to 100 particles/µL was achieved with CDs-GFET sensor for exosome detection with the capability for further improvements. The results were further supported by atomic force microscopy (AFM) and fluorescent microscopy measurements. The high-performance CDs-GFET biosensors will aid the development of an ultrahigh sensitivity biosensing platform based on graphene for rapid and early diagnosis of diseases.


Assuntos
Técnicas Biossensoriais , Carbono/química , Exossomos/química , Pontos Quânticos/química , Transistores Eletrônicos , Tamanho da Partícula , Propriedades de Superfície
16.
Herz ; 46(2): 172-177, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31555894

RESUMO

BACKGROUND: Patients with a left ventricular ejection fraction (LVEF) ≤35% should be protected from sudden cardiac death with an implantable cardioverter-defibrillator (ICD). The onset of the effect of optimal medical therapy (OMT) is unclear, and a wearable cardioverter-defibrillator (WCD) can bridge this period. PATIENTS AND METHODS: Our study analyzed 104 patients (age, 68.9 ± 11.7 years; 81% [84/104] male) whose first diagnosis included an LVEF <35%. After exclusion of reversible causes for LVEF reduction and initiation/adjustment of the OMT, the WCD was employed. The LVEF and indication for ICD were re-evaluated after 62 ± 36 days. The LVEF development and implantation rate were correlated with underlying disease (ischemic [ICM] or nonischemic cardiomyopathy [NICM]), comorbidities, and age/gender. RESULTS: The wearing time of the WCD was 22.8 ± 1.9 h/day. An LVEF improvement from 28.5 ± 6.4% to 40 ± 11.7% was achieved through OMT (p < 0.0001). An improvement in LVEF of up to more than 35% was achieved in 66 of 104 patients (63%), and only 37% of patients were subsequently given an ICD. This affected 41% of patients with ICM and 30% of patients with NICM (p = 0.205). Notably, no ICD interventions were observed over 362 ± 89.5 days after implantation in the ICD-receiver group. CONCLUSION: The indication for ICD can be re-evaluated after 2 months. Patients with NICM respond better to OMT compared with ICM patients. The LVEF recovered to >35% in >60% of cases.


Assuntos
Desfibriladores Implantáveis , Dispositivos Eletrônicos Vestíveis , Idoso , Idoso de 80 Anos ou mais , Morte Súbita Cardíaca/prevenção & controle , Cardioversão Elétrica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
17.
Front Physiol ; 11: 596844, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363477

RESUMO

BACKGROUND: The REACT DX registry evaluates standard therapies to episodes of long-lasting atrial tachyarrhythmias and assesses the quality of sensing and stability of the lead and the implantable cardioverter-defibrillator (ICD) (BIOTRONIK Lumax VR-T DX and successors) over at least a 1-year follow-up period. OBJECTIVE: To study the association between the risk of de novo device-detected atrial fibrillation (AF), the autonomic perturbations before the onset of paroxysmal AF and a 7-days heart rate variability (7dHRV) 1 month after ICD implantation. METHODS: The registry consists of 234 patients implanted with an ICD, including 10 with de novo long-lasting atrial tachyarrhythmias with no prior history of AF. The patients were matched via the propensity-score methodology as well as for properties directly influencing the ECGs recorded using GE CardioMem CM 3000. Heart rate variability (HRV) analysis was performed using standard parameters from time- and frequency-domains, and from non-linear dynamics. RESULTS: No linear HRV was associated with an increased risk of AF (p = n.s.). The only significant approach was derived from symbolic dynamics with the parameter "forbidden words" which distinguished both groups on all 7 days of measurements (p < 0.05), thereby quantifying the heart rate complexity (HRC) as drastically lower in the de novo AF group. CONCLUSION: Cardiac autonomic dysfunction denoted by low HRC may be associated with higher AF incidence. For patients with mild to moderate heart failure, standard HRV parameters are not appropriate to quantify cardiac autonomic perturbations before the onset of AF. Further studies are needed to determine the individual risk for AF that would enable interventions to restore autonomic balance in the general population.

18.
ACS Appl Mater Interfaces ; 12(44): 49786-49794, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33079533

RESUMO

Heterostructures involving two-dimensional (2D) transition metal dichalcogenides and other materials such as graphene have a strong potential to be the fundamental building block of many electronic and optoelectronic applications. The integration and scalable fabrication of such heterostructures are of the essence in unleashing the potential of these materials in new technologies. For the first time, we demonstrate the growth of few-layer MoS2 films on graphene via nonaqueous electrodeposition. Through methods such as scanning and transmission electron microscopy, atomic force microscopy, Raman spectroscopy, energy- and wavelength-dispersive X-ray spectroscopies, and X-ray photoelectron spectroscopy, we show that this deposition method can produce large-area MoS2 films with high quality and uniformity over graphene. We reveal the potential of these heterostructures by measuring the photoinduced current through the film. These results pave the way toward developing the electrodeposition method for the large-scale growth of heterostructures consisting of varying 2D materials for many applications.

19.
Biosens Bioelectron ; 170: 112673, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33038584

RESUMO

Currently the world is being challenged by a public health emergency caused by the coronavirus pandemic (COVID-19). Extensive efforts in testing for coronavirus infection, combined with isolating infected cases and quarantining those in contact, have proven successful in bringing the epidemic under control. Rapid and facile screening of this disease is in high demand. This review summarises recent advances in strategies reported by international researchers and engineers concerning how to tackle COVID-19 via rapid testing, mainly through nucleic acid- and antibody- testing. The roles of biosensors as powerful analytical tools are emphasized for the detection of viral RNAs, surface antigens, whole viral particles, antibodies and other potential biomarkers in human specimen. We critically review in depth newly developed biosensing methods especially for in-field and point-of-care detection of SARS-CoV-2. Additionally, this review describes possible future strategies for virus rapid detection. It helps researchers working on novel sensor technologies to tailor their technologies in a way to address the challenge for effective detection of COVID-19.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas Biossensoriais , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Testes Imediatos , Animais , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico/economia , Técnicas de Laboratório Clínico/instrumentação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/economia , Desenho de Equipamento , Humanos , Pandemias , Testes Imediatos/economia , SARS-CoV-2 , Fatores de Tempo
20.
Clin Res Cardiol ; 109(10): 1223-1231, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32030497

RESUMO

AIMS: To investigate the long-term prognostic value of aspiration thrombectomy in conjunction with primary percutaneous coronary intervention (PCI) compared to conventional PCI in patients with non-ST-elevation myocardial infarction (NSTEMI). METHODS: In the randomized TATORT-NSTEMI (Thrombus aspiration in thrombus containing culprit lesions in non-ST-elevation myocardial infarction) trial, NSTEMI patients with thrombus containing culprit lesions were randomized to either PCI with aspiration thrombectomy or conventional PCI. The endpoint was a combination of all-cause death, reinfarction and new congestive heart failure. RESULTS: From 440 patients initially randomized, outcome data were available in 432 (98.2%) patients at a median follow-up of 4.9 (interquartile range [IQR] 4.4-5.0) years. Thrombectomy was associated with a significant reduction of the combined endpoint compared to conventional PCI (19.9% vs. 30.7%, p = 0.01). This finding was primarily driven by a reduced rate of reinfarction with thrombectomy (3.4% vs. 10.3%, p = 0.01). Thrombectomy was still independently associated with the combined endpoint after multivariable adjustment (hazard ratio [HR] 0.47, 95% confidence interval [CI] 0.30-0.76, p = 0.002). Findings were consistent across all analyzed subgroups (p values for interaction all > 0.05). CONCLUSIONS: In NSTEMI, thrombus aspiration is associated with favorable clinical outcome during long-term follow-up. CLINICAL TRIAL REGISTRATION: NCT01612312.


Assuntos
Trombose Coronária/terapia , Infarto do Miocárdio sem Supradesnível do Segmento ST/terapia , Intervenção Coronária Percutânea/métodos , Trombectomia/métodos , Idoso , Feminino , Seguimentos , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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