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1.
Arq Bras Cardiol ; 121(6): e20230684, 2024 Jun.
Artigo em Português, Inglês | MEDLINE | ID: mdl-39109691

RESUMO

BACKGROUND: There are no randomized studies comparing the maintenance of sinus rhythm after catheter ablation (CA) concerning treatment with antiarrhythmic drugs (AA) in elderly patients with paroxysmal atrial fibrillation (AF). OBJECTIVES: To compare the clinical results of pulmonary vein (PV) isolation with the second-generation PVAC Gold catheter against AA treatment in elderly people with recurrent symptomatic paroxysmal AF, refractory to at least one AA, and without structural heart disease. METHODS: Sixty patients with paroxysmal AF ≥ 65 years old were randomized to two forms of treatment: group 1: CA and group 2: AA drugs. The primary outcome was the AF recurrence-free rate after at least one year of follow-up. Secondary outcomes were: progression to persistent forms of AF, impact on quality of life (QOLF), and complications. The significance level adopted in the statistical analysis was 5% (p<0.05). RESULTS: The AF recurrence-free rate was 80% (10% with amiodarone) in the CA group, after 1.3 procedures per patient and 65% in the AA group (60% with amiodarone), (p = 0.119) in an average follow-up of 719 days (Q1: 566; Q3: 730). The persistent AF free rate was 83.4% in the AC group and 67.7% in the AA group (p = 0.073) Both strategies showed an improvement in the AFQoL score during follow-up (p < 0.001), with no difference between the groups. Although without clinical repercussions or impact on the intellectual assessment test, 25% of patients in the CA group showed signs of cerebral embolization on brain MRI. CONCLUSIONS: Both strategies for maintaining sinus rhythm promoted an improvement in the quality of life of elderly patients with symptomatic AF, with no statistical difference in the clinical outcomes. Additional studies using technologies with a better safety profile are needed to evaluate the benefits of CA in elderly patients with AF.


FUNDAMENTO: Não existem estudos randomizados comparando a manutenção do ritmo sinusal após ablação por cateter (AC) em relação ao tratamento com fármacos antiarrítmicos (AA) em pacientes idosos portadores fibrilação atrial (FA) paroxística. OBJETIVOS: Comparar os resultados clínicos do isolamento das veias pulmonares (VPs) com o cateter PVAC Gold de segunda geração com o uso de AA em idosos com FA paroxística sintomática, recorrente, apesar do uso de fármacos AA. MÉTODOS: Sessenta pacientes com FA paroxística ≥ 65 anos e sem cardiopatias estruturais foram randomizados para duas formas de tratamento: grupo 1: AC e grupo 2: AA. O desfecho primário foi a taxa livre de recorrência de FA após pelo menos um ano de seguimento. Os desfechos secundários foram: progressão para formas persistentes de FA, impacto na qualidade de vida (QVFA) e complicações. O nível de significância adotado na análise estatística foi de 5% (p<0,05). RESULTADOS: A taxa livre de recorrência de FA foi de 80% (10% com amiodarona) no grupo AC, após 1,3 procedimentos por paciente e de 65% no grupo AA (60% com amiodarona), (p = 0,119) num seguimento médio de 719 dias (Q1: 566; Q3: 730). A taxa livre de FA persistente foi de 83,4% no grupo AC e de 67,7% no grupo AA (p = 0,073). Ambas as estratégias apresentaram melhora no escore de QVFA durante o seguimento (p < 0,001), sem diferença entre os grupos. Embora sem repercussão clínica ou impacto no teste de avaliação intelectual, 25% dos pacientes do grupo PVAC apresentou sinais de embolização cerebral na RNM cerebral. CONCLUSÕES: Ambas as estratégias para manutenção do ritmo sinusal promoveram melhora na qualidade de vida de pacientes idosos com FA sintomática, sem diferença estatística nos desfechos clínicos preconizados. Estudos adicionais usando tecnologias com melhor perfil de segurança são necessários para avaliar os benefícios da AC em pacientes idosos com FA.


Assuntos
Antiarrítmicos , Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Qualidade de Vida , Humanos , Fibrilação Atrial/cirurgia , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/terapia , Fibrilação Atrial/fisiopatologia , Antiarrítmicos/uso terapêutico , Feminino , Masculino , Idoso , Ablação por Cateter/métodos , Resultado do Tratamento , Veias Pulmonares/cirurgia , Recidiva , Amiodarona/uso terapêutico , Fatores de Tempo
2.
Small ; : e2400351, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874126

RESUMO

Schwarzites are porous (spongy-like) carbon allotropes with negative Gaussian curvatures. They are proposed by Mackay and Terrones inspired by the works of the German mathematician Hermann Schwarz on Triply-Periodic Minimal Surfaces (TPMS). This review presents and discusses the history of schwarzites and their place among curved carbon nanomaterials. The main works on schwarzites are summarized and are available in the literature. Their unique structural, electronic, thermal, and mechanical properties are discussed. Although the synthesis of carbon-based schwarzites remains elusive, recent advances in the synthesis of zeolite-templates nanomaterials have brought them closer to reality. Atomic-based models of schwarzites are translated into macroscale ones that are 3D-printed. These 3D-printed models are exploited in many real-world applications, including water remediation and biomedical ones.

3.
An Acad Bras Cienc ; 96(2): e20231336, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747801

RESUMO

The disease coronavirus COVID-19 has been the cause of millions of deaths worldwide. Among the proteins of SARS-CoV-2, non-structural protein 12 (NSP12) plays a key role during COVID infection and is part of the RNA-dependent RNA polymerase complex. The monitoring of NSP12 polymorphisms is extremely important for the design of new antiviral drugs and monitoring of viral evolution. This study analyzed the NSP12 mutations detected in circulating SARS-CoV-2 during the years 2020 to 2022 in the population of the city of Manaus, Amazonas, Brazil. The most frequent mutations found were P323L and G671S. Reports in the literature indicate that these mutations are related to transmissibility efficiency, which may have contributed to the extremely high numbers of cases in this location. In addition, two mutations described here (E796D and R914K) are close and have RMSD that is similar to the mutations M794V and N911K, which have been described in the literature as influential on the performance of the NSP12 enzyme. These data demonstrate the need to monitor the emergence of new mutations in NSP12 in order to better understand their consequences for the treatments currently used and in the design of new drugs.


Assuntos
COVID-19 , RNA-Polimerase RNA-Dependente de Coronavírus , SARS-CoV-2 , Humanos , Brasil , Simulação por Computador , COVID-19/virologia , COVID-19/transmissão , Mutação/genética , SARS-CoV-2/genética , Proteínas não Estruturais Virais/genética , RNA-Polimerase RNA-Dependente de Coronavírus/genética , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo
4.
An Acad Bras Cienc ; 96(1): e20230218, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808812

RESUMO

Latin American and the Caribbean regions (LAC) harbor one of the most biodiverse areas of the world, the Neotropics. True bugs (Hemiptera: Heteroptera) are a diverse lineage of insects, with more than 45,000 species, particularly speciose in the Neotropical region. True bugs are fundamental in the dynamics of natural and modified ecosystems, with several species critical to agriculture and public health. We compiled Heteroptera research in LAC from 1998-2022 using bibliographic databases. Productivity, collaborative networks, and the main topics studied were analyzed. A total of 1,651 Heteroptera studies from LAC were found, with continuous growth being 2021 the most prolific. Four categories (Taxonomy of extant species, Faunistic inventories and new records, Pest species biology, and Community ecology) represent most of the published research. About 60 percent of the records evaluated correspond to five families (Pentatomidae, Reduviidae, Coreidae, Miridae, and Rhyparochromidae). We emphasize the need to keep working on Heteroptera taxonomy because it will allow further advances in other areas such as phylogenetic analyses, biogeography, ecology, and natural history, among others. The results of our analyses characterize the current state of heteropterology in the region, establishing a baseline for future studies and efforts to broaden the knowledge of the group.


Assuntos
Heterópteros , América Latina , Animais , Região do Caribe , Heterópteros/classificação , Pesquisa/tendências , Pesquisa/classificação , Bibliometria
10.
JACC Clin Electrophysiol ; 9(11): 2315-2328, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37676203

RESUMO

BACKGROUND: The subxiphoid pericardial access is technically difficult and has a considerable rate of complications, thus transatrial access may be an alternative. OBJECTIVES: This study sought to assess the feasibility and safety of this strategy regarding periprocedural period and after 1-week follow-up. METHODS: The investigators performed epicardial mapping through transatrial puncture in 20 swine. Animals were divided into group A, in which aspiration of the sheath was performed to maintain negative pressure after the withdraw of the catheters, and group B, in which a device (Konar-MF VSD Occluder) was delivered to occlude the right atrial appendage perforation. Bleeding was investigated immediately and 1 week after. RESULTS: Access was safe in 19 of 20 animals (95%) with small amount of bleeding (6.4 ± 6 mL). In group A (n = 10), 1 animal presented hemopericardium right after the puncture. In the other 9, epicardial ablation was performed and 60.0 ± 28.0 mL of blood was aspirated without events. After 1 week, fibrin-hemorrhagic pericarditis was identified in 3 animals. In group B (n = 10), reaching the epicardial surface was possible in all animals. An adequate position of the prosthesis was obtained in 90% (9 of 10). One death occurred in the immediate postoperative period, secondary to pneumothorax. After 1 week, postmortem analysis showed absence of pericardial bleeding and a normal-appearing pericardium in the 8 animals with adequate prosthesis position. CONCLUSIONS: Transatrial access allows epicardial mapping and ablation. Sheath removal after negative pressure contributes to achieving acute bleeding control but does not prevent its occurrence. The use of the device prevents bleeding and hemorrhagic pericarditis.


Assuntos
Mapeamento Epicárdico , Pericardite , Animais , Suínos , Estudos de Viabilidade , Mapeamento Epicárdico/métodos , Pericárdio/cirurgia , Hemorragia/etiologia
11.
Vascular ; : 17085381231193492, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37540895

RESUMO

PURPOSE: Postoperative complications after major surgery, especially vascular procedures, are associated with a significant increase in costs and mortality. Previous studies evaluating general anesthesia versus regional or neuraxial anesthesia for infrainguinal bypass have produced conflicting results. The main aim of the present study is to review current evidence on the application of regional or general anesthesia in patients undergoing infrainguinal bypass surgery and its potential favorable effects on postoperative outcomes. CONTENTS: Patients undergoing vascular surgery often have multiple comorbidities, and it is important to outline both benefits and risks of regional anesthesia techniques. Neuraxial anesthesia in vascular surgery allows overall avoidance of general anesthesia and does provide short-term benefits beyond analgesia. Previous observational studies suggest that neuraxial anesthesia for lower limb revascularization may reduce morbidity and length of stay. However, evidence of long-term benefits is lacking in most procedures and further work is still warranted. CONCLUSIONS: Neuraxial anesthesia is usually an effective anesthesia technique for infrainguinal bypass surgery. Elderly patients and those with underlying respiratory problems may display some benefit from neuraxial anesthesia. Further evaluation within institutions should be performed to identify which patients would most benefit from regional techniques. Notably, systemic antithrombotic and anticoagulation therapy is common among this population and may affect anesthetic choices.

13.
Zootaxa ; 5263(3): 401-410, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37044979

RESUMO

The rare Neotropical Discocephalini (Heteroptera: Pentatomidae) monotypic genus Glyphuchus Stål, 1860 and its type species Glyphuchus sculpturatus Stål, 1860 are known only from the female holotype. Here, they are redescribed based on a recently collected specimen and on the holotype. The male of the genus is described for the first time based on a specimen collected in a protected area of the Atlantic Rain Forest, in southeastern Brazil. General morphology and male and female genitalia are described and compared to those of other Discocephalini genera. Photos of the main morphological characters are presented, as well as photos of the living and preserved specimens. The relevance of protected areas for studies on biodiversity and natural history is highlighted.


Assuntos
Hemípteros , Heterópteros , Feminino , Masculino , Animais
14.
Sci Rep ; 13(1): 6937, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37117229

RESUMO

The formation of our Solar System and planetary defense strategies are among the priorities to be investigated in the next years by the space science community. As in-situ missions to small bodies (as comets and asteroids) are options to conduct these investigations, this paper proposes a combination of methodologies to produce low-cost transfers to near-earth asteroids (NEAs). Low-cost trajectories derived from retrograde periodic orbits around [Formula: see text] are taken as a starting point for the escape of the Earth-Moon system and, as the vehicle exits the sphere of influence of Earth, the deployment of an adjustable solar sail guarantees the interception of the target in a predetermined position and time of flight. Different sail loadings (164, 61 and 30 g/m2) are tested and a case study to the NEA 65,803 Didymos is presented. The results show economies in the velocity increments required by the mission up to 8.48%, although a longer time of flight might be needed depending on the sail loading.

16.
J Interv Card Electrophysiol ; 66(7): 1581-1587, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36602693

RESUMO

BACKGROUND: Cardiac magnetic resonance (CMR) allowed to precisely identify the substrate in scar-related ventricular tachycardia (VT). New software has been developed to define the 3D scar and corridors to help VT ablation by integrating the scar and electroanatomical mapping (EAM). The objective of this study is to evaluate the results of VT ablation aided by the integration of EAM and CMR software processed scar. METHODS: We selected patients that underwent VT ablation with the integration of EAM and CMR processed using ADAS software and imported to the CARTO system using VTK file format. RESULTS: From 2019 to 2021, eight patients (mean age 63 ± 4.4, 62.5% male; EF 47 ± 12%) underwent CMR-aided VT ablation. Mean procedural time was 281 ± 77 min. There was of 9 ± 4.4 epicardial and 7.9 ± 4.3 endocardial bulls eye segments with at least 2 g of border zone or core scar. In a median follow-up time of 532 days (Q1: 284, Q3: 688), three patients (37.5%) presented VT recurrence, all three underwent a second procedure, with no VT recurrence on the follow-up. No patient died in the follow-up. CONCLUSION: CMR aided is ablation is feasible and effective in patients with scar related VT.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Humanos , Masculino , Feminino , Cicatriz/diagnóstico por imagem , Cicatriz/cirurgia , Cicatriz/patologia , Resultado do Tratamento , Imageamento por Ressonância Magnética/métodos , Taquicardia Ventricular/diagnóstico por imagem , Taquicardia Ventricular/cirurgia , Espectroscopia de Ressonância Magnética , Ablação por Cateter/métodos
19.
Nanotechnology ; 34(10)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36399779

RESUMO

Vertical nanostructure technologies are becoming more important for the down scaling of nanoelectronic devices such as logic transistors or memories. Such devices require dense vertical nanostructured channel arrays (VNCA) that can be fabricated through a top-down approach based on group IV materials. We present progresses on the top-down fabrication of highly anisotropic and ultra-dense Si1-xGex(x= 0, 0.2, 0.5) VNCAs. Dense nanowire and nanosheet patterns were optimized through high resolution lithography and transferred onto Si1-xGexsubstrates by anisotropic reactive ion etching with a fluorine chemistry. The right gas mixtures for a given Ge content resulted in perfectly vertical and dense arrays. Finally we fabricated oxide shell/SiGe core heterostructures by dry- and wet-thermal oxidation and evaluated their applicability for nanostructure size engineering, as already established for silicon nanowires. The impact of the nanostructured shape (wire or sheet), size and Ge content on the oxide growth were investigated and analysed in detail through transmission electron microscopy.

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