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1.
Sensors (Basel) ; 22(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35458809

RESUMO

In this article, we present our research achievements regarding the development of a remote sensing system for motor pulse acquisition, as a first step towards a complete neuroprosthetic arm. We present the fabrication process of an implantable electrode for nerve impulse acquisition, together with an innovative wirelessly controlled system. In our study, these were combined into an implantable device for attachment to peripheral nerves. Mechanical and biocompatibility tests were performed, as well as in vivo testing on pigs using the developed system. This testing and the experimental results are presented in a comprehensive manner, demonstrating that the system is capable of accomplishing the requirements of its designed application. Most significantly, neural electrical signals were acquired and transmitted out of the body during animal experiments, which were conducted according to ethical regulations in the field.


Assuntos
Sistema Nervoso Periférico , Tecnologia de Sensoriamento Remoto , Potenciais de Ação , Animais , Eletrodos Implantados , Nervos Periféricos/fisiologia , Suínos
2.
J Mater Sci Mater Electron ; 33(25): 19998-20011, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38625349

RESUMO

Recently the emissions of volatile organic compounds (VOCs) in the atmosphere have increased dramatically with rapid development of urbanization and industry. This led to a large decline in air quality around the world, which resulted in a heavy impact on human health. Therefore, new/cheap detection devices for VOCs are of high interest. Formaldehyde (FA) is a very toxic VOC, which damages the respiratory system even in the smallest doses and short exposure time. Zinc oxide (ZnO)/nickel oxide (NiO) heterostructures were synthesized using an economical route: firstly, NiO was prepared by liquid exfoliation technique and deposited by dip-coating on alumina ceramic transducers with two interdigital gold (Au) electrodes, followed by low-temperature hydrothermal growth of ZnO. The as-prepared sensors were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM-EDAX), and X-Ray fluorescence (XRF). The response/recovery of ZnO/NiO heterostructure-based microsensors for formaldehyde was investigated at room temperature, in agreement with modern sensing requirements. The sensor operating voltage was varied between 1.5 and 5.0 V direct current (DC), to achieve the best sensor performance.

3.
Molecules ; 27(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35164084

RESUMO

Nanocomposite materials have seen increased adoption in a wide range of applications, with toxic gas detection, such as carbon monoxide (CO), being of particular interest for this review. Such sensors are usually characterized by the presence of CO absorption sites in their structures, with the Langmuir reaction model offering a good description of the reaction mechanism involved in capturing the gas. Among the reviewed sensors, those that combined polymers with carbonaceous materials showed improvements in their analytical parameters such as increased sensitivities, wider dynamic ranges, and faster response times. Moreover, it was observed that the CO reaction mechanism can differ when measured in mixtures with other gases as opposed to when it is detected in isolation, which leads to lower sensitivities to the target gas. To better understand such changes, we offer a complete description of carbon nanostructure-based chemosensors for the detection of CO from the sensing mechanism of each material to the water solution strategies for the composite nanomaterials and the choice of morphology for enhancing a layers' conductivity. Then, a series of state-of-the-art resistive chemosensors that make use of nanocomposite materials is analyzed, with performance being assessed based on their detection range and sensitivity.

4.
Sensors (Basel) ; 21(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809497

RESUMO

In recent years, research into the field of materials for flexible sensors and fabrication techniques directed towards wearable devices has helped to raise awareness of the need for new sensors with healthcare applicability. Our goal was to create a wearable flexible pressure sensor that could be integrated into a clinically approved blood pressure monitoring device. The sensor is built from a microfluidic channel encapsulated between two polymer layers, one layer being covered by metal transducers and the other being a flexible membrane containing the microfluidic channel, which also acts as a sealant for the structure. The applied external pressure deforms the channel, causing changes in resistance to the microfluidic layer. Electrical characterization has been performed in 5 different configurations, using alternating current (AC) and (DC) direct current measurements. The AC measurements for the fabricated pressure sensor resulted in impedance values at tens of hundreds of kOhm. Our sensor proved to have a high sensitivity for pressure values between 0 and 150 mm Hg, being subjected to repeatable external forces. The novelty presented in our work consists in the unique technological flow for the fabrication of the flexible wearable pressure sensor. The proposed miniaturized pressure sensor will ensure flexibility, low production cost and ease of use. It is made of very sensitive microfluidic elements and biocompatible materials and can be integrated into a wearable cuffless device for continuous blood pressure monitoring.


Assuntos
Dispositivos Eletrônicos Vestíveis , Pressão Sanguínea , Impedância Elétrica , Microfluídica , Monitorização Fisiológica
5.
Sensors (Basel) ; 21(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807640

RESUMO

Developing a sensing layer with high electroactive properties is an important aspect for proper functionality of a wearable sensor. The polymeric nanocomposite material obtained by a simple electropolymerization on gold interdigitated electrodes (IDEs) can be optimized to have suitable conductive properties to be used with direct current (DC) measurements. A new layer based on polyaniline:poly(4-styrenesulfonate) (PANI:PSS)/single-walled carbon nanotubes (SWCNT)/ferrocene (Fc) was electrosynthesized and deposed on interdigital transducers (IDT) and was characterized in detail using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoemission spectroscopy (XPS), and X-ray diffraction (XRD). The sensor characteristics of the material towards carbon monoxide (CO) in the concentration range of 10-300 ppm were examined, showing a minimal relative humidity interference of only 1% and an increase of sensitivity with the increase of CO concentration. Humidity interference could be controlled by the number of CV cycles when a compact layer was formed and the addition of Fc played an important role in the decrease of humidity. The results for CO detection can be substantially improved by optimizing the number of deposition cycles and enhancing the Fc concentration. The material was developed for selective detection of CO in real environmental conditions and shows good potential for use in a wearable sensor.


Assuntos
Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Eletrodos , Ouro , Metalocenos
6.
Sensors (Basel) ; 21(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807664

RESUMO

The low-power sensing platform proposed by the Convergence project is foreseen as a wireless, low-power and multifunctional wearable system empowered by energy-efficient technologies. This will allow meeting the strict demands of life-style and healthcare applications in terms of autonomy for quasi-continuous collection of data for early-detection strategies. The system is compatible with different kinds of sensors, able to monitor not only health indicators of individual person (physical activity, core body temperature and biomarkers) but also the environment with chemical composition of the ambient air (NOx, COx, NHx particles) returning meaningful information on his/her exposure to dangerous (safety) or pollutant agents. In this article, we introduce the specifications and the design of the low-power sensing platform and the different sensors developed in the project, with a particular focus on pollutant sensing capabilities and specifically on NO2 sensor based on graphene and CO sensor based on polyaniline ink.


Assuntos
Grafite , Dispositivos Eletrônicos Vestíveis , Feminino , Humanos , Masculino , Monitorização Fisiológica
7.
Age Ageing ; 45(3): 427-30, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27013500

RESUMO

BACKGROUND: transcatheter aortic valve implantation (TAVI) has emerged as an alternative to surgical aortic valve replacement for patients with severe aortic stenosis considered inoperable or at high operative risk, but the long-term outcome remains unknown. HYPOTHESIS: we assessed the 4-year clinical and echocardiographic outcomes of patients undergoing TAVI with the self-expanding Medtronic CoreValve prosthesis. METHODS: sixty-three patients (mean age 80 ± 6 years) with severe aortic stenosis (AS) at high risk for surgical aortic valve replacement (Logistic EuroSCORE 28.8 ± 10.9%) were included in this study. RESULTS: all-cause cumulative mortality at 1, 2, 3 and 4 years was 14.3, 25.4, 28.6 and 36.5%, respectively. The cumulative incidence of documented major stroke at 4 years was 6.3%. In survivors, there was a significant improvement in functional status at 4 years. Paravalvular leak (trivial/mild to moderate) was observed in the majority of patients post-TAVI with no case of progression to severe regurgitation at 4-year follow-up. In multivariate analysis, independent predictor for increased all-cause mortality was left ventricular ejection fraction <40% (HR: 5.347, 95% CI: 1.126-25.381, P = 0.035). CONCLUSION: our study demonstrated favourable long-term (4 years) outcomes after successful TAVI using the third-generation Medtronic CoreValve device.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/terapia , Bioprótese , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estenose da Valva Aórtica/mortalidade , Estudos de Coortes , Ecocardiografia/métodos , Feminino , Seguimentos , Idoso Fragilizado , Avaliação Geriátrica , Humanos , Estimativa de Kaplan-Meier , Masculino , Modelos de Riscos Proporcionais , Desenho de Prótese , Medição de Risco , Estatísticas não Paramétricas , Taxa de Sobrevida , Fatores de Tempo , Substituição da Valva Aórtica Transcateter/mortalidade , Resultado do Tratamento
8.
J Thromb Thrombolysis ; 40(2): 193-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25863809

RESUMO

Aim of the present study was to record the antithrombotic approach in AF and non-AF patients undergoing TAVI, and to compare the efficiency of the used regimens combination. Antithrombotic approach of patients undergoing TAVI remains a challenging dispute. It becomes even more complex when need for anticoagulant treatment is required due to concurrent atrial fibrillation. Consecutive patients with severe symptomatic aortic stenosis treated with TAVI, were retrospectively studied. All patients were divided into two groups, matched to age, depending on the existence of atrial fibrillation. The primary end-point was the composite of MACE, while the secondary end-point was the occurrence of major bleeding at follow-up. A total of 80 patients were included in the study. Out of them, 20 patients (80.2 ± 5.4 years) suffered from concurrent atrial fibrillation. This group was matched with 20 patients (80.6 ± 3.7 years) with no need for anticoagulation. AF-group patients were treated with clopidogrel plus acenocoumarol for 3 months. Following that, acetylsalicylic acid plus acenocoumarol were prescribed. Non-AF patients were treated with 3 months clopidogrel plus acetylsalicylic acid followed by single acetylsalicylic acid medication. No statistical significant differences in MACE between AF and non-AF group were identified (p = 0.705, phi coefficient = 0.06) (mean follow-up 23.4 ± 14 months). Similarly, there was no statistical significant difference for bleedings among the AF and non-AF patient group (p = 0.658, phi coefficient = 0.14). In patients undergoing TAVI with CoreValve, with concurrent AF, treatment with clopidogrel plus acenocoumarol for 3 months, followed by acetylsalicylic acid plus acenocoumarol, seems safe and effective enough in long-term follow-up.


Assuntos
Acenocumarol/administração & dosagem , Estenose da Valva Aórtica/terapia , Fibrilação Atrial/terapia , Fibrinolíticos/administração & dosagem , Ticlopidina/análogos & derivados , Substituição da Valva Aórtica Transcateter , Acenocumarol/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Clopidogrel , Feminino , Fibrinolíticos/efeitos adversos , Seguimentos , Humanos , Masculino , Ticlopidina/administração & dosagem , Ticlopidina/efeitos adversos
9.
Biosensors (Basel) ; 14(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38248408

RESUMO

There is great interest in the development of prosthetic limbs capable of complex activities that are wirelessly connected to the patient's neural system. Although some progress has been achieved in this area, one of the main problems encountered is the selective acquisition of nerve impulses and the closing of the automation loop through the selective stimulation of the sensitive branches of the patient. Large-scale research and development have achieved so-called "cuff electrodes"; however, they present a big disadvantage: they are not selective. In this article, we present the progress made in the development of an implantable system of plug neural microelectrodes that relate to the biological nerve tissue and can be used for the selective acquisition of neuronal signals and for the stimulation of specific nerve fascicles. The developed plug electrodes are also advantageous due to their small thickness, as they do not trigger nerve inflammation. In addition, the results of the conducted tests on a sous scrofa subject are presented.


Assuntos
Antebraço , Inflamação , Humanos , Eletrodos Implantados , Potenciais de Ação , Automação
10.
Catheter Cardiovasc Interv ; 81(6): 1061-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23197467

RESUMO

OBJECTIVES: This study sought to investigate whether the site of common femoral artery (CFA) cannulation in regard to the inferior epigastric artery (IEA) is associated with the incidence of vascular complications in patients undergoing transfemoral aortic valve implantation (TAVI). BACKGROUND: Vascular access complications are a main issue during TAVI and have been associated with significant increase of morbidity and mortality. The need for establishment of reliable predictors for these serious events remains important. METHODS: A total of 90 patients, who had undergone TAVI, were retrospectively studied. Vascular complications were defined as major and minor according to the Valve Academic Research Consortium (VARC) criteria. Patients were divided into high cannulation site (CS) group and low CS group depending on the common femoral artery puncture site position, in regards to the most inferior border of the IEA. RESULTS: Vascular complications were significantly more frequent in the high CS group versus the low CS group (32.3% vs. 11.9%, P = 0.039). High cannulation remained an independent predictor of vascular complications after adjustment for known risk factors (OR: 4.827, CI: 1.441-16.168; P = 0.011). CONCLUSIONS: In patients undergoing transfemoral TAVI, arterial puncture above the most inferior border of the IEA is associated with vascular complications.


Assuntos
Pontos de Referência Anatômicos , Estenose da Valva Aórtica/terapia , Cateterismo Cardíaco , Cateterismo Periférico , Artérias Epigástricas , Artéria Femoral , Implante de Prótese de Valva Cardíaca/métodos , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/efeitos adversos , Cateterismo Periférico/efeitos adversos , Distribuição de Qui-Quadrado , Artérias Epigástricas/diagnóstico por imagem , Feminino , Artéria Femoral/diagnóstico por imagem , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Modelos Logísticos , Masculino , Tomografia Computadorizada Multidetectores , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Punções , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Lesões do Sistema Vascular/etiologia
11.
Gels ; 9(5)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37232947

RESUMO

Detection of greenhouse gases is essential because harmful gases in the air diffuse rapidly over large areas in a short period of time, causing air pollution that will induce climate change with catastrophic consequences over time. Among the materials with favorable morphologies for gas detection (nanofibers, nanorods, nanosheets), large specific surfaces, high sensitivity and low production costs, we chose nanostructured porous films of In2O3 obtained by the sol-gel method, deposited on alumina transducers, with gold (Au) interdigitated electrodes (IDE) and platinum (Pt) heating circuits. Sensitive films contained 10 deposited layers, involving intermediate and final thermal treatments to stabilize the sensitive film. The fabricated sensor was characterized using AFM, SEM, EDX and XRD. The film morphology is complex, containing fibrillar formations and some quasi-spherical conglomerates. The deposited sensitive films are rough, thus favoring gas adsorption. Ozone sensing tests were performed at different temperatures. The highest response of the ozone sensor was recorded at room temperature, considered to be the working temperature for this specific sensor.

12.
J Clin Med ; 12(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37373740

RESUMO

BACKGROUND: A paravalvular leak (PVL) is a complication following valve replacement, which may lead to heart failure and hemolysis. The aim of this study is to investigate whether the clinical outcome after transcatheter PVL closure differs according to the prominent indication of the procedure (symptoms of heart failure or hemolysis). METHODS: The data of consecutive patients who had transcatheter treatment for PVL between July 2011 and September 2022 in five Greek centers were analyzed. The primary endpoint was the technical, and clinical success rates with regards to the prominent indication of paravalvular leak closure. The secondary endpoints included the evaluation and comparison of the clinical and technical success in relation to the type of valve that was treated (aortic or mitral) as well as the survival analysis in relation to the closure indication and type of valve that was treated. RESULTS: In total, 60 patients were retrospectively studied (39% men, mean age 69.5 ± 11 years). Regarding the primary outcomes, the technical success in patients mainly suffering from hemolysis was 86.1%, while in those presenting heart failure it was 95.8%, p = 0.387. Furthermore, the clinical success was 72.2% and 87.5% among hemolysis and heart failure patients, respectively, p = 0.210. During the follow-up period, the two-year survival rates were significantly better for patients treated for the aortic valve (78.94%) compared to those in the mitral position (48.78%), p = 0.014. In total, 25 patients died (41.7%) during 24 months of follow-up. CONCLUSIONS: Transcatheter paravalvular leak closure can be performed with high technical and clinical success rates without any difference according to the prominent indication of closure.

13.
Gels ; 9(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37367146

RESUMO

Healthcare professionals face an ongoing challenge in managing both acute and chronic wounds, given the potential impact on patients' quality of life and the limited availability of expensive treatment options. Hydrogel wound dressings offer a promising solution for effective wound care due to their affordability, ease of use, and ability to incorporate bioactive substances that enhance the wound healing process. Our study aimed to develop and evaluate hybrid hydrogel membranes enriched with bioactive components such as collagen and hyaluronic acid. We utilized both natural and synthetic polymers and employed a scalable, non-toxic, and environmentally friendly production process. We conducted extensive testing, including an in vitro assessment of moisture content, moisture uptake, swelling rate, gel fraction, biodegradation, water vapor transmission rate, protein denaturation, and protein adsorption. We evaluated the biocompatibility of the hydrogel membranes through cellular assays and performed instrumental tests using scanning electron microscopy and rheological analysis. Our findings demonstrate that the biohybrid hydrogel membranes exhibit cumulative properties with a favorable swelling ratio, optimal permeation properties, and good biocompatibility, all achieved with minimal concentrations of bioactive agents.

14.
JACC Cardiovasc Interv ; 16(22): 2722-2732, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38030358

RESUMO

BACKGROUND: Scarce data exist on the evolution of device-related thrombus (DRT) after left atrial appendage closure (LAAC). OBJECTIVES: This study sought to assess the incidence, predictors, and clinical impact of persistent and recurrent DRT in LAAC recipients. METHODS: Data were obtained from an international multicenter registry including 237 patients diagnosed with DRT after LAAC. Of these, 214 patients with a subsequent imaging examination after the initial diagnosis of DRT were included. Unfavorable evolution of DRT was defined as either persisting or recurrent DRT. RESULTS: DRT resolved in 153 (71.5%) cases and persisted in 61 (28.5%) cases. Larger DRT size (OR per 1-mm increase: 1.08; 95% CI: 1.02-1.15; P = 0.009) and female (OR: 2.44; 95% CI: 1.12-5.26; P = 0.02) were independently associated with persistent DRT. After DRT resolution, 82 (53.6%) of 153 patients had repeated device imaging, with 14 (17.1%) cases diagnosed with recurrent DRT. Overall, 75 (35.0%) patients had unfavorable evolution of DRT, and the sole predictor was average thrombus size at initial diagnosis (OR per 1-mm increase: 1.09; 95% CI: 1.03-1.16; P = 0.003), with an optimal cutoff size of 7 mm (OR: 2.51; 95% CI: 1.39-4.52; P = 0.002). Unfavorable evolution of DRT was associated with a higher rate of thromboembolic events compared with resolved DRT (26.7% vs 15.1%; HR: 2.13; 95% CI: 1.15-3.94; P = 0.02). CONCLUSIONS: About one-third of DRT events had an unfavorable evolution (either persisting or recurring), with a larger initial thrombus size (particularly >7 mm) portending an increased risk. Unfavorable evolution of DRT was associated with a 2-fold higher risk of thromboembolic events compared with resolved DRT.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Acidente Vascular Cerebral , Tromboembolia , Trombose , Humanos , Feminino , Incidência , Apêndice Atrial/diagnóstico por imagem , Resultado do Tratamento , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/terapia , Fibrilação Atrial/complicações , Tromboembolia/diagnóstico por imagem , Tromboembolia/epidemiologia , Tromboembolia/etiologia , Trombose/diagnóstico por imagem , Trombose/epidemiologia , Trombose/etiologia , Acidente Vascular Cerebral/etiologia
15.
Sensors (Basel) ; 12(8): 11372-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23112661

RESUMO

The following paper describes the design and functions of a miniaturized integrated platform for optical and electrical monitoring of cell cultures and the necessary steps in the fabrication and testing of a silicon microchip Micro ElectroMechanical Systems (MEMS)-based technology for cell data recording, monitoring and stimulation. The silicon microchip consists of a MEMS machined device containing a shank of 240 µm width, 3 mm long and 50 µm thick and an enlarged area of 5 mm × 5 mm hosting the pads for electrical connections. Ten platinum electrodes and five sensors are placed on the shank and are connected with the external electronics through the pads. The sensors aim to monitor the pH, the temperature and the impedance of the cell culture. The electrodes are bidirectional and can be used both for electrical potential recording and stimulation of cells. The fabrication steps are presented, along with the electrical and optical characterization of the system. The target of the research is to develop a new and reconfigurable platform according to the particular applications needs, as a tool for the biologist, chemists and medical doctors working is the field of cell culture monitoring in terms of growth, maintenance conditions, reaction to electrical or chemical stimulation (drugs, toxicants, etc.). HaCaT (Immortalised Human Keratinocyte) cell culture has been used for demonstration purposes in order to provide information on the platform electrical and optical functions.


Assuntos
Técnicas de Cultura de Células/instrumentação , Sistemas Microeletromecânicos/instrumentação , Imagem Óptica/instrumentação , Compostos de Anilina/química , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Condutividade Elétrica , Desenho de Equipamento , Humanos , Concentração de Íons de Hidrogênio , Sistemas Microeletromecânicos/métodos , Microeletrodos , Nanofibras , Imagem Óptica/métodos , Temperatura
16.
Nanomaterials (Basel) ; 12(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36145032

RESUMO

Undoped and Zn-doped ITO (ITO:Zn) multifunctional thin films were successfully synthesized using the sol-gel and dipping method on three different types of substrates (glass, SiO2/glass, and Si). The effect of Zn doping on the optoelectronic, microstructural, and gas-sensing properties of the films was investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), spectroscopic ellipsometry (SE), Raman spectroscopy, Hall effect measurements (HE), and gas testing. The results showed that the optical constants, the transmission, and the carrier numbers were correlated with the substrate type and with the microstructure and the thickness of the films. The Raman study showed the formation of ITO films and the incorporation of Zn in the doped film (ITO:Zn), which was confirmed by EDX analysis. The potential use of the multifunctional sol-gel ITO and ITO:Zn thin films was proven for TCO applications or gas-sensing experiments toward CO2. The Nyquist plots and equivalent circuit for fitting the experimental data were provided. The best electrical response of the sensor in CO2 atmosphere was found at 150 °C, with activation energy of around 0.31 eV.

17.
Pharmaceuticals (Basel) ; 16(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36678545

RESUMO

Green chemistry is a pharmaceutical industry tool, which, when implemented correctly, can lead to a minimization in resource consumption and waste. An aqueous extract of Salix alba L. was employed for the efficient and rapid synthesis of silver/gold particle nanostructures via an inexpensive, nontoxic and eco-friendly procedure. The nanoparticles were physicochemically characterized using ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), X-ray diffraction (XRD) and scanning electron microscopy (SEM), with the best stability of up to one year in the solution obtained for silver nanoparticles without any chemical additives. A comparison of the antimicrobial effect of silver/gold nanoparticles and their formulations (hydrogels, ointments, aqueous solutions) showed that both metallic nanoparticles have antibacterial and antibiofilm effects, with silver-based hydrogels having particularly high antibiofilm efficiency. The highest antibacterial and antibiofilm efficacies were obtained against Pseudomonas aeruginosa when using silver nanoparticle hydrogels, with antibiofilm efficacies of over 75% registered. The hydrogels incorporating green nanoparticles displayed a 200% increased bacterial efficiency when compared to the controls and their components. All silver nanoparticle formulations were ecologically obtained by "green synthesis" and were shown to have an antimicrobial effect or potential as keratinocyte-acting pharmaceutical substances for ameliorating infectious psoriasis wounds.

18.
Circ J ; 75(9): 2105-12, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21712606

RESUMO

BACKGROUND: Residual platelet reactivity (RPR) after clopidogrel loading, measured by the VerifyNow assay, has been shown to predict 12-month clinical events in patients with acute coronary syndromes. However, links between coronary angiographic findings and outcome in patients with ST-elevation myocardial infarction (STEMI), with RPR have not been reported. We investigated whether RPR is associated with the amount of intracoronary thrombus burden (TB) in patients with STEMI undergoing unexpectedly-delayed primary percutaneous coronary intervention (pPCI). Moreover, we evaluated whether RPR might influence coronary flow and myocardial perfusion immediately post-pPCI. METHODS AND RESULTS: The VerifyNow assay was used to determine RPR after clopidogrel loading, expressed in P2Y12-Reaction-Units (PRU). Intracoronary-TB was angiographically estimated and stratified as TB-Grade-A, -B and -C. Thrombolysis In Myocardial Infarction (TIMI) flow and Myocardial Blush (MB) were also estimated post-PCI. A total of 74 consecutive patients who presented with STEMI were enrolled in the study. Patients with greater TB presented significantly higher PRU-levels (174.1 ± 91.5, 196.23 ± 113.4 and 252.8 ± 107.8 for TB-Grade A, B and C, respectively; P=0.044). PRU-levels >251.5 were shown to predict Large-TB (LTB; TB-Grade-C) (sensitivity=57.9%; specificity=77.8%; P=0.014). Impaired TIMI-flow and MB after PCI were significantly associated with higher PRU-levels (P < 0.001). CONCLUSIONS: Among the studied patients, those with a higher RPR after clopidogrel loading presented larger intracoronary TB, worse post-PCI myocardial flow and perfusion.


Assuntos
Angioplastia Coronária com Balão , Trombose Coronária/terapia , Infarto do Miocárdio/terapia , Inibidores da Agregação Plaquetária , Ticlopidina/análogos & derivados , Síndrome Coronariana Aguda/fisiopatologia , Síndrome Coronariana Aguda/terapia , Idoso , Clopidogrel , Circulação Coronária/efeitos dos fármacos , Trombose Coronária/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Ticlopidina/administração & dosagem , Ticlopidina/efeitos adversos , Fatores de Tempo
19.
Hellenic J Cardiol ; 62(6): 416-422, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33617960

RESUMO

BACKGROUND: Paravalvular leak (PVL) is a common complication following valve replacement, which leads to heart failure and hemolysis. Transcatheter PVL closure has emerged as a reliable alternative with promising results. We quote the combined three-center experience of PVL patients treated percutaneously. METHODS: Consecutive patients treated percutaneously for PVL were retrospectively studied. Procedural characteristics, inhospital, and long-term clinical outcomes were assessed. Technical (successful deployment) and clinical (NYHA and/or hemolysis improvement) success were evaluated. RESULTS: In total, 39 patients treated for PVL in either the aortic (12 patients) or the mitral (27 patients) position were studied. Amplatzer Vascular Plug III was the most commonly used device among the 45 devices totally implanted. Postprocedurally, the rates of at least moderate PVL (87.5% preprocedurally vs 10.5% at discharge) and functional status (mean NYHA class 2.8 ± 0.7 on admission vs 1.5 ± 0.8 at follow-up) were statistically significantly improved. Total population technical success rate was 89.7%, being comparable between patients treated for mitral or aortic valve PVLs (92.6% vs 83.3%, respectively). Clinical success was achieved in 82.1% of patient cohort without statistical difference among those with isolated aortic or mitral PVL or among those with PVL closure an indication of heart failure or hemolysis. During a mean follow-up of 33.5 months, five patients died, including one periprocedural death. CONCLUSIONS: This multicenter recorded experience confirms that percutaneous PVL closure can be performed with high technical and clinical success rates and limited complications that lead to significant PVL reduction and functional status improvement.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Cateterismo Cardíaco , Seguimentos , Próteses Valvulares Cardíacas/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Falha de Prótese , Estudos Retrospectivos , Resultado do Tratamento
20.
Am J Cardiol ; 154: 78-85, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243938

RESUMO

The impact of the antiplatelet regimen and the extent of associated platelet inhibition on cerebrovascular microembolic events during transcatheter aortic valve implantation (TAVI) are unknown. Our aim was to evaluate the effects of ticagrelor versus clopidogrel and of platelet inhibition on the number of cerebrovascular microembolic events in patients undergoing TAVI. Patients scheduled for TAVI were randomized previous to the procedure to either aspirin and ticagrelor or to aspirin and clopidogrel. Platelet inhibition was expressed in P2Y12 reaction units (PRU) and percentage of inhibition. High intensity transient signals (HITS) were assessed with transcranial Doppler (TCD). Safety outcomes were recorded according to the VARC-2 definitions. Among 90 patients randomized, 6 had an inadequate TCD signal. The total number of procedural HITS was lower in the ticagrelor group (416.5 [324.8, 484.2]) (42 patients) than in the clopidogrel group (723.5 [471.5, 875.0]) (42 patients), p <0.001. After adjusting for the duration of the procedure, diabetes, extra-cardiac arteriopathy, BMI, hypertension, aortic valve calcium content, procedural ACT, and pre-implantation balloon valvuloplasty, patients on ticagrelor had on average 256.8 (95% CI: [-335.7, -176.5]) fewer total procedural HITS than patients on clopidogrel. Platelet inhibition was greater with ticagrelor 26 [10, 74.5] PRU than with clopidogrel 207.5 (120 to 236.2) PRU, p <0.001, and correlated significantly with procedural HITS (r = 0.5, p <0.05). In conclusion, ticagrelor resulted in fewer procedural HITS, compared with clopidogrel, in patients undergoing TAVI, while achieving greater platelet inhibition.


Assuntos
Estenose da Valva Aórtica/cirurgia , Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Embolia Intracraniana/prevenção & controle , Complicações Intraoperatórias/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Ticagrelor/uso terapêutico , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Idoso de 80 Anos ou mais , Terapia Antiplaquetária Dupla/métodos , Feminino , Humanos , Embolia Intracraniana/diagnóstico por imagem , Embolia Intracraniana/epidemiologia , Complicações Intraoperatórias/diagnóstico por imagem , Complicações Intraoperatórias/epidemiologia , Masculino , Ultrassonografia Doppler Transcraniana
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