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1.
Kardiol Pol ; 82(4): 382-390, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38493454

RESUMO

BACKGROUND: In a population under 45 years of age, the predominant causes of sudden cardiac death (SCD) are inherited cardiac diseases. Determining the underlying cause may help identify relatives at risk and prevent further events but is more difficult if an autopsy has not been performed. AIMS: We aimed to assess the diagnostic value of clinical and genetic screening in relatives of young non-autopsied sudden unexplained death (SUD) victims. MATERIAL AND METHODS: Eighty-seven relatives of 65 young non-autopsied SUD victims from 39 families were evaluated from 2016 to 2019. The relatives underwent extensive noninvasive cardiac workup. Genetic examinations were performed in 39 families. RESULTS: The definite diagnoses were made in 17 of 39 (44%) families. Cardiomyopathies were identified in 10 families (5 hypertrophic, 4 dilated, and 1 arrhythmogenic), followed by long QT syndrome (5 families). In 3 families, probable diagnoses were made, whereas in 20 families no diagnosis was achieved. In total, definite and probable diagnoses were made in 18 and 5 patients, respectively. All affected relatives were offered medical management, one of them died of heart failure and one underwent transplantation during the median follow-up of 3 years. Disease-causing variants were found in 7 of 39 (18%) probands; all in families with a definite diagnosis. Variants of unknown significance were found in 2 probands. CONCLUSION: Screening of relatives of SUD victims is warranted and may save lives, even if it is not guided by autopsy results. Genetic testing in families without the disease phenotype has little effectiveness.


Assuntos
Morte Súbita Cardíaca , Testes Genéticos , Humanos , Feminino , Masculino , Morte Súbita Cardíaca/etiologia , Adulto , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , Criança , Predisposição Genética para Doença , Síndrome do QT Longo/genética , Síndrome do QT Longo/diagnóstico
2.
J Phys Chem A ; 127(26): 5580-5590, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37352233

RESUMO

We demonstrate a proof-of-concept of a new analytical technique to measure relative F atom exposure at the surfaces of fluorinated materials. The method is based on reactive-atom scattering (RAS) of Al atoms, produced by pulsed laser ablation of solid Al at 532 nm. The properties of the incident ground-state Al were characterized by laser-induced fluorescence (LIF); at typical ablation fluences, the speed distribution is approximately Maxwellian at ∼45000 K, with a most-probable kinetic energy of 187 kJ mol-1 and a mean of 560 kJ mol-1 When these Al atoms impact the surfaces of perfluorinated solids (poly(tetrafluorethylene), PTFE) or liquids (perfluoropolyether, PFPE), gas-phase AlF products are clearly detectable by LIF on the AlF A-X band. Quantitative AlF yields were compared for a small representative set of a widely studied family of ionic liquids based on the common 1-alkyl-3-methylimidazolium ([Cnmim]+) cation. Yields of (1.9 ± 0.2):1 were found from [C2mim][Tf2N] and [C8mim][Tf2N], containing the common fluorinated bis(trifluoromethylsulfonyl)imide anion ([Tf2N]-). This is in quantitative agreement with previous independent low-energy ion scattering (LEIS) measurements and consistent with other independent results indicating that the longer cationic alkyl chains cover a larger fraction of the liquid surface and hence reduce anion exposure. The expected null result was obtained for the ionic liquid [C2mim][EtSO4] which contains no fluorine. These results open the way for further characterization and the potential application of this new variant of the RAS-LIF method.

3.
Angew Chem Int Ed Engl ; 62(29): e202304075, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37158668

RESUMO

A chiral bispyrene macrocycle designed for exclusive intermolecular excimer fluorescence upon aggregation was synthesized by a double hydrothiolation of a bis-enol ether macrocycle followed by intramolecular oxidation of free thiols. Unusually high stereoselectivity was achieved for the thiol-ene additions under templated conditions and Et3 B/O2 radical initiation. After enantiomer separation (chiral stationary phase HPLC), aqueous conditions provoked aggregation. Detailed structural evolution was afforded by ECD/CPL monitoring. Three regimes can be observed and characterized by strong modifications in chiroptical patterns under, at, or above a 70 % H2 O : THF threshold. In luminescence, high glum dissymmetry factors values were obtained, up to 0.022, as well as a double sign inversion of CPL signals during the aggregation, a behavior rationalized by time-dependent density functional theory (TDDFT) calculations. Langmuir layers of enantiopure disulfide macrocycles were formed at the air-water interface and transferred onto solid substrates to afford Langmuir-Blodgett films, which were then studied by AFM and UV/ECD/fluorescence/CPL.

4.
Langmuir ; 39(6): 2135-2151, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36739536

RESUMO

Recently the focus of the Langmuir-Blodgett technique as a method of choice to transfer monolayers from the air/water interface onto solid substrates in a controllable fashion has been shifting toward purely hydrophobic gold and silver nanoparticles. The fundamental interactions between particles that become relevant in the absence of polar groups range from dispersive attractions from the metal cores and repulsions between ligand shells to weaker entropic factors. The layer evolution is explored, starting with interfacial self-assembly upon solution spreading and domain and circular island formation, which subsequently merge into a complete monolayer and finally form multilayers or macroscopic wrinkles. Moreover, structural properties such as the core:ligand size ratio are investigated in the context of dispersive forces, whereby the nanoparticles with small cores and long ligands tend not to aggregate sufficiently to produce continuous films, those with large cores and short ligands were found to aggregate irreversibly, and those in between the two extremes were concluded to be able to form highly organized crystalline films. Similarly, the characteristics of the spreading solution such as the concentration and the solvent type crucially influence the film crystallinity, with the deciding factor being the degree of affinity between the capping ligand and the solvent used for spreading. Finally, the most common strategies employed to enhance the mechanical stability of the metal nanoparticle films along with the recent attempts to functionalize the particles in attempts to improve their applicability in the industry are summarized and evaluated in relation to their future prospects. One of the objectives of this feature article is to elucidate the differences between hydrophobic metal nanoparticles and typical amphiphilic molecules that the majority of the literature in the field describes and to familiarize the reader with the knowledge required to design Langmuir-Blodgett nanoparticle systems as well as the strategies to improve existing ones.

5.
Angew Chem Int Ed Engl ; 62(16): e202215746, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36728623

RESUMO

A bidentate chiral dithiol (diBINAS) is utilised to bridge Au25 nanoclusters to form oligomers. Separation by size allows the isolation of fractions that are stable thanks to the bidentate nature of the linker. The structure of the products is elucidated by small-angle X-ray scattering and calculated using density functional theory. Additional structural details are studied by diffusion-ordered nuclear magnetic resonance spectroscopy, transmission electron microscopy and matrix-assisted laser desorption/ionization time of flight mass spectrometry. Significant changes in the optical properties are analysed by UV/Vis and fluorescence spectroscopies, with the latter demonstrating a strong emission enhancement. Furthermore, the emergent chiral characteristics are studied by circular dichroism. Due to the geometry constraints of the nanocluster assemblies, diBINAS can be regarded as a templating molecule, taking a step towards the directed self-assembly of metal clusters.

6.
J Colloid Interface Sci ; 630(Pt B): 28-36, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36327730

RESUMO

HYPOTHESIS: Langmuir-Blodgett (LB) technique allows the deposition of gold nanoparticles and nanoclusters (atomically precise nanoparticles below 2 nm in diameter) onto solid substrates with an unprecedented degree of control and high transfer ratios. Nanoclusters are expected to follow the crinkle folding mechanism, which promotes the formation of trilayers of nanoparticles but kinetically disfavors the formation of the fourth layer. EXPERIMENTS: LB films of Au38(SC2H4Ph)24 nanocluster were prepared at a range of surface pressures in the bilayer/trilayer regime and their internal structure was analyzed with X-ray Reflectivity (XRR) and Grazing-Incidence Wide-Angle X-ray Scattering (GIWAXS). Bimodal atomic force microscopy (AFM) imaging was used to quantify the elastic modulus, which can be correlated with the topography at the same point on the surface. FINDINGS: Nanocluster bilayers and trilayers exhibited the elastic moduli of ca. 1.2 GPa and 0.9 GPa respectively. Films transferred in the 20-25 mN/m surface pressure regime displayed a particular propensity to form highly vertically organized trilayers. Further compression resulted in disorganization of the layers. Crucially, the use of two cantilevers of contrasting stiffness for bimodal AFM measurements has demonstrated a new approach to quantify the mechanical properties of ultrathin films without the use of deconvolution algorithms to remove the substrate contribution.


Assuntos
Ouro , Nanopartículas Metálicas , Microscopia de Força Atômica , Raios X , Módulo de Elasticidade
8.
Small ; 17(27): e2005954, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33559304

RESUMO

Langmuir-Blodgett technique is utilized to deposit ultrathin films of Au38 (SC2 H4 Ph)24 nanocluster onto solid surfaces such as mica and silicon. The morphologies of the films transferred at various surface pressures within the mono/bi/trilayer regime are studied by atomic force microscopy (AFM). The time spent on the water surface before the deposition has a decisive effect on the final ordering of nanoclusters within the network and is studied by fast AFM, X-ray reflectivity, and grazing-incidence wide-angle X-ray scattering.

9.
Minerva Cardiol Angiol ; 69(5): 502-509, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32657554

RESUMO

BACKGROUND: Impaired myocardial tissue reperfusion affects prognosis of patients with ST-segment elevation myocardial infarction (STEMI) treated with percutaneous coronary intervention (PCI) and can be identified by ST-segment analysis. To date, evaluation of the myocardial tissue reperfusion of the right ventricle (RV) among the patients treated with PCI for inferior STEMI with right ventricular infarction (RVI) has not been made yet. METHODS: Patients with inferior STEMI were screened for RVI. Tissue reperfusion was evaluated by maximal residual ST-segment deviation post PCI, independently for the RV and for inferior wall. Myocardial injury was assessed by the peak creatine kinase-mb (CK-MB) value. RESULTS: Among 456 patients with inferior STEMI, concomitant RVI occurred in 153 (33.5%) subjects (59.86±10.35 years old, 71.9% females). Tissue reperfusion of LV was present in 75 (49%), whereas 55 (35.9%) had both successful LV and RV reperfusion. Among 97 (63.4%) with successful tissue reperfusion of RV, 55 (56.7%) had associated successful tissue reperfusion of inferior wall. Adequate LV reperfusion was accompanied by RV in over 73.3% of patients (P=0.006). Mean peak CK-MB was lower in the group with adequate versus impaired RV tissue-perfusion (197±143 vs. 305±199 U/L, P=0.021 respectively). CONCLUSIONS: Impaired reperfusion of RV is observed in more than one third of inferior STEMIs with RVI and is not strictly associated with impaired reperfusion of inferior wall and clinical or angiographic variables, therefore ST-segment analysis for RV is mandatory.


Assuntos
Infarto Miocárdico de Parede Inferior , Intervenção Coronária Percutânea , Disfunção Ventricular Direita , Idoso , Angioplastia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Infarto Miocárdico de Parede Inferior/terapia , Masculino , Pessoa de Meia-Idade , Reperfusão Miocárdica , Intervenção Coronária Percutânea/efeitos adversos
13.
Am J Cardiol ; 126: 66-72, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32340714

RESUMO

Available prediction models are inaccurate in elderly who underwent transcatheter aortic valve implantation (TAVI). The aim of present study was to analyze the separate and combined prognostic values of baseline HDL-C and C-reactive protein (CRP) levels in patients treated successfully with TAVI who had complete 2-year follow-up. We analyzed 334 patients treated with TAVI from 01/2010 to 07/2017 who had measurements of HDL-C and CRP on admission or during qualification for the procedure. Baseline HDL-C ≤46 mg/dl (areas under the curve [AUC] = 0.657) and CRP ≥0.20 mg/dl (AUC = 0.634) were predictive of 2-year mortality. After stratification with both cutoffs, patients with low HDL-C and concomitant high CRP most often had LVEF ≤50% and were high risk as per EuroSCORE II. Those with isolated CRP elevation had the lowest frequency of LVEF ≤50%, but more sarcopenia (based on psoas muscle area). After adjustment in the multivariate analysis for other identified predictors including EuroSCORE II and statin therapy, isolated HDL-C ≤46 mg/dl (identified in 40 patients) and isolated CRP ≥0.20 mg/dl (n = 109) were both independent predictors of 2-year mortality (hazard ratio [HR] = 2.92 and HR = 2.42, respectively) compared with patients with both markers within established cutoffs (n = 105) who had the lowest 2-year mortality (9.5%). Patients with both markers exceeding cutoffs (n = 80) had the highest risk (HR = 4.53) with 2-year mortality of 42.5%. High CRP was associated with increased mortality within the first year of follow-up, whereas low HDL-C increased mortality in the second year. The combination of both markers with EuroSCORE II enhanced mortality prediction (AUC = 0.697). In conclusion, low baseline HDL-C and high CRP jointly contribute to the prediction of increased all-cause mortality after TAVI.


Assuntos
Proteína C-Reativa/análise , HDL-Colesterol/sangue , Mortalidade , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/cirurgia , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Insuficiência Renal Crônica/mortalidade , Medição de Risco , Sensibilidade e Especificidade , Fatores Sexuais , Volume Sistólico
16.
J Invasive Cardiol ; 31(10): E301-E302, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31567120

RESUMO

An 85-year-old, symptomatic man with severe chronic mitral regurgitation MR, left ventricular ejection fraction of 30%, permanent atrial fibrillation, and EuroScore II of 13% qualified for MitraClip procedure. TEE and electrocardiography documented acute hemodynamic changes throughout the procedure.


Assuntos
Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Hemodinâmica/fisiologia , Insuficiência da Valva Mitral/cirurgia , Idoso de 80 Anos ou mais , Ecocardiografia Transesofagiana , Seguimentos , Humanos , Masculino , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/fisiopatologia , Desenho de Prótese , Índice de Gravidade de Doença
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