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1.
Am Heart J ; 270: 13-22, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38253304

RESUMO

BACKGROUND: Safety and feasibility of transcatheter aortic valve replacement (TAVR) without balloon aortic valvuloplasty (BAV) using the SAPIEN 3 balloon-expandable device has been previously demonstrated. The impact on long-term valve hemodynamic performances and outcomes remains however unknown. We evaluate long-term clinical and hemodynamic results according to the implant strategy (direct TAVR vs BAV pre-TAVR) in patients included in the DIRECTAVI randomized trial (NCT02729519). METHODS: Clinical and echocardiographic follow-up until January 2023 was performed for all patients included in the DIRECTAVI trial since 2016 (n = 228). The primary endpoint was incidence of moderate/severe hemodynamic valve deterioration (HVD), according to the Valve Academic Research defined Consortium-3 criteria (increase in mean gradient ≥10 mmHg resulting in a final mean gradient ≥20 mmHg, or new/worsening aortic regurgitation of 1 grade resulting in ≥ moderate aortic regurgitation). RESULTS: Median follow-up was 3.8 (2.2-4.7) years. Mean age at follow-up was 87 ± 6.7 years. No difference in incidence of HVD in the direct implantation group compared to the BAV group was found (incidence of 1.97 per 100 person-years and 1.45 per 100 person-years, respectively, P = 0.6). Prevalence of predicted prothesis-patient mismatch was low (n = 13 [11.4%] in the direct TAVR group vs n = 15 [13.2%] in BAV group) and similar between both groups (P = .7). Major outcomes including death, stroke, hospitalization for heart failure and pacemaker implantation were similar between both groups, (P = .4, P = .7, P = .3, and P = .3 respectively). CONCLUSION: Direct implantation of the balloon-expandable device in TAVR was not associated with an increased risk of moderate/severe HVD or major outcomes up to 6-year follow-up. These results guarantee wide use of direct balloon-expandable valve implantation, when feasible. CLINICAL TRIALS REGISTRATION NUMBER: NCT05140317.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Valvuloplastia com Balão , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Idoso de 80 Anos ou mais , Substituição da Valva Aórtica Transcateter/métodos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Seguimentos , Insuficiência da Valva Aórtica/cirurgia , Resultado do Tratamento , Fatores de Tempo , Desenho de Prótese , Valvuloplastia com Balão/efeitos adversos
2.
Medicina (Kaunas) ; 57(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34684084

RESUMO

Inflammatory processes are deeply involved in ischemia-reperfusion injuries (IRI) and ventricular remodelling (VR) after a ST-segment elevation myocardial infarction (STEMI). They are associated with clinical adverse events (heart failure and cardiovascular death) adding damage to the myocardium after reperfusion. Moreover, acute myocardial infarction (AMI) induces a local sympathetic denervation leading to electrical instability and arrythmia. Colchicine, a well-known alkaloid with direct anti-inflammatory effects, was shown to reduce the myocardial necrosis size and limit the VR. In a recent proof of concept study, colchicine appears to prevent sympathetic denervation in a mice model of ischemia/reperfusion, but not in the necrosis or in the border zone areas. The Colchicine to Prevent Sympathetic Denervation after an AMI study (COLD-MI) is an ongoing, confirmative, prospective, monocentre, randomized, open-label trial. The COLD-MI trial aims to evaluate the intensity of sympathetic denervation after AMI and its potential modulation due to low dose colchicine. Sympathetic denervation will be noninvasively evaluated using single-photon emission computed tomography (SPECT). After a first episode of STEMI (Initial TIMI flow ≤ 1) and primary percutaneous coronary intervention (PPCI), patients will be randomized (n = 56) in a 1:1 ratio to either receive colchicine or not for 30 days. The primary end point will be the percentage of myocardial denervation measured by 123I-metaiodobenzylguanidine (123I-MIBG) SPECT at a 6-month follow-up. The main secondary end points will be basic ECG parameters (QRS duration, corrected QT) and HRV parameters from a 24 hour-recording Holter at 1- and 6-months follow-up. Results from this study will contribute to a better understanding of the cardioprotective effect of colchicine after AMI. The present study describes the rationale, design, and methods of the trial.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Animais , Colchicina/uso terapêutico , Humanos , Camundongos , Infarto do Miocárdio/tratamento farmacológico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Simpatectomia
4.
RSC Adv ; 13(24): 16529-16535, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37274409

RESUMO

In this paper, we have studied the critical behavior and the magnetocaloric effect (MCE) simulation for the La0.75Ca0.1Na0.15MnO3 (LCNMO) compound at the second order ferromagnetic-paramagnetic phase transition. The optimized critical exponents, based on the Kouvel-Fisher method, were found to be: ß = 0.48 and γ = 1. These obtained values supposed that the Mean Field Model (MFM) is the proper model to analyze adequately the MCE in the LCNMO sample. The isothermal magnetization M(H, T) and the magnetic entropy change -ΔSM(H, T) curves were successfully simulated using three models, namely the Arrott-Noakes equation (ANE) of state, Landau theory, and MFM. The framework of the MFM allows us to estimate magnetic entropy variation in a wide temperature range within the thermodynamics of the model and without using the usual numerical integration of Maxwell relation.

6.
RSC Adv ; 13(41): 28632-28641, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37780730

RESUMO

In this study, we meticulously deposited an Al-doped ZnO nanoparticle thin film on a p-type silicon substrate using the precise sputtering method. We conducted a comprehensive exploration of the film's structure, morphology, and optical properties. X-ray diffraction (XRD) confirmed its polycrystalline wurtzite configuration with a dominant (002) orientation. High-resolution scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed a uniformly textured surface adorned with densely packed nanoparticles. Regarding optical properties, the Al-doped ZnO thin film exhibited exceptional transmittance exceeding 80% across visible and near-infrared spectra. Moving on to electrical characteristics, we assessed the Au/Al-doped ZnO/p-Si/Al heterostructure under dark and illuminated conditions. Through current-voltage (I-V) and impedance measurements, we observed significant improvements in conductivity and performance under illumination. Notably, there was an increase in current conduction and a reduction in impedance, highlighting the advantages of illumination. Collectively, these findings emphasize the promising potential of the Au/Al-doped ZnO/p-Si/Al heterostructure, particularly in the realms of optoelectronic devices and photovoltaics. With its ability to efficiently mobilize charges and adeptly assimilate light, this heterostructure stands as a frontrunner for transformative applications in these technologically vital domains.

7.
RSC Adv ; 13(43): 30230-30242, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37854492

RESUMO

Pure zinc oxide nanoparticles, as well as those doped with 3% calcium, aluminum, and gallium, were synthesized using a sol-gel method and then deposited onto an alumina substrate for sensing tests. The resulting nanoparticles were characterized using a variety of techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), UV-VIS-NIR absorption spectroscopy, and photoluminescence (PL) measurements, to examine their structural, morphological, and optical properties. The prepared nanoparticles were found to have the hexagonal wurtzite structure of ZnO with a P63mC space group. The UV-Vis-IR spectra showed that the samples are highly absorbent in the UV range, while the PL spectra confirmed the presence of many defects in the ZnO structure, such as oxygen vacancies and zinc interstitials. The doped samples exhibited more defects than the pure sample. SEM images of the deposited film surface showed agglomerates with a spherical shape and confirmed the nanometer scale size of our prepared samples, as corroborated by the TEM images. The EDX spectra indicated the high purity of the ZnO deposited films, with a high presence of Zn and O and the presence of the doped elements (Ca, Al, and Ga) in each doped sample. Sensing tests were performed on ZnO, Ca3%-doped ZnO (C3ZO), Al3%-doped ZnO (A3ZO), and Ga3%-doped ZnO (G3ZO) sensors in the presence of volatile organic compounds (VOCs) gases such as ethanol, formaldehyde, methanol, and acetone at low concentrations. The sensors exhibited high responses to low ppm level concentrations of the VOCs gases. At a low operational temperature of 250 °C, the C3ZO sensor had the highest response to 5 ppm of ethanol, methanol, and formaldehyde gases compared to the pure and other doped sensors. Additionally, the A3ZO sensor exhibited the highest response to acetone gas. In conclusion, our findings suggest that the doping of zinc oxide can enhance the low concentration detection of VOCs gases, with the C3ZO and A3ZO sensors showing the highest response to specific gases.

8.
J Clin Med ; 10(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34830668

RESUMO

Sleep disturbances are frequent among patients with heart failure (HF). We hypothesized that self-reported sleep disturbances are associated with a poor prognosis in patients with HF. A longitudinal study of 119 patients with HF was carried out to assess the association between sleep disturbances and the occurrence of major cardiovascular events (MACE). All patients with HF completed self-administered questionnaires on sleepiness, fatigue, insomnia, quality of sleep, sleep patterns, anxiety and depressive symptoms, and central nervous system (CNS) drugs intake. Patients were followed for a median of 888 days. Cox models were used to estimate the risk of MACE associated with baseline sleep characteristics. After adjustment for age, the risk of a future MACE increased with CNS drugs intake, sleep quality and insomnia scores as well with increased sleep latency, decreased sleep efficiency and total sleep time. However, after adjustment for left ventricular ejection fraction and hypercholesterolemia the HR failed to be significant except for CNS drugs and total sleep time. CNS drugs intake and decreased total sleep time were independently associated with an increased risk of MACE in patients with HF. Routine assessment of self-reported sleep disturbances should be considered to prevent the natural progression of HF.

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