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1.
Nanotechnology ; 35(28)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38579687

RESUMEN

Oxygen vacancies and heteroatom doping play important role in oxygen reduction activity of metal oxides. Developing efficient modification method is one of the key issues in catalysts research. Room temperature plasma treatment, with the advantages of mild working conditions, no emissions and high efficiency, is a new catalyst modification method developed in recent years. In this work, hydrothermal synthesizedα-MnO2nanorods are treated in NH3plasma at room temperature. In the reducing atmosphere, oxygen vacancies and N doping are achieved simultaneously on the surface. The NH3plasma etched MnO2demonstrate a significant enhanced oxygen reduction activity with half-wave potential of 0.84 V, limiting current density of 6.32 mA cm-2and transferred electrons number of 3.9. The Mg-air battery with N-MnO2display a maximum power density of 76.3 mW cm-2as well as stable discharge performance. This work provides new ideas for preparing efficient and cost-effective method to boost the catalysts activity.

2.
ACS Appl Mater Interfaces ; 16(10): 13316-13325, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38427779

RESUMEN

The application of rechargeable lithium metal batteries is challenged by intractable issues of uncontrollable Li dendrite growth that result in poor cycle life and safety risks. In this work, an air-stable interphase is developed to protect the lithium metal anode (LMA) via a facile solution-based approach. The Ag-embedded fluoride-rich interphase not only creates abundant lithiophilic sites for homogenizing Li nucleation and growth but also resists severe air erosion to protect the LMA beneath and enable decent cycling stability. As a result, the Ag-F-rich interphase enables flat Li deposition on LMA, which is clearly observed in the operando Li plating experiments. Paired with a LiFePO4 cathode (11.8 mg cm-2), the Ag-F-rich interphase-modified LMA enables 300 stable cycles at 0.5 C, delivering a capacity retention ratio as high as 91.4%. Even after being exposed to air for 1 h, the modified LMA still runs smoothly for over 120 cycles with ignorable capacity decay, exhibiting great air stability. This work proves the concept of functionalizing the interphase on the LMA to enable good cycling performance even under severe air erosion.

3.
Small ; 20(3): e2304528, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37649165

RESUMEN

Liquid metal batteries (LMBs) are promising candidates for grid-scale energy storage due to their exceptional kinetics, scalability, and long lifespan derived from the distinctive three-liquid-layer structure. However, the positive electrode (such as Bi) suffers from insufficient wettability on the current collector, resulting in excess electrical resistance and uneven current distribution, thus deteriorating the cycling stability. Here the incorporation of 4 mol% Se into Bi-based metal is proposed producing an interface layer with highly surface-active property that decreases the electrode's contact angle with the 304 stainless-steel (SUS304) from 144.7° to 74.3°, so as to improve the wettability. The as-prepared 20 Ah Li || Bi-Se4 (the content of Se is 4 mol% of Bi) cell cycled 1200 times with capacity fade rate of merely 0.00174% per cycle. This facile and effective approach provides a pathway toward the production of stable cells with an extended lifespan and boosts the practical implementation of LMBs.

4.
Angew Chem Int Ed Engl ; 62(31): e202306877, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37278885

RESUMEN

To be successfully implemented, an efficient conversion, affordable operation and high values of CO2 -derived products by electrochemical conversion of CO2 are yet to be addressed. Inspired by the natural CaO-CaCO3 cycle, we herein introduce CaO into electrolysis of SnO2 in affordable molten CaCl2 -NaCl to establish an in situ capture and conversion of CO2 . In situ capture of anodic CO2 from graphite anode by the added CaO generates CaCO3 . The consequent co-electrolysis of SnO2 and CaCO3 confines Sn in carbon nanotube (Sn@CNT) in cathode and increases current efficiency of O2 evolution in graphite anode to 71.9 %. The intermediated CaC2 is verified as the nuclei to direct a self-template generation of CNT, ensuring a CO2 -CNT current efficiency and energy efficiency of 85.1 % and 44.8 %, respectively. The Sn@CNT integrates confined responses of Sn cores to external electrochemical or thermal stimuli with robust CNT sheaths, resulting in excellent Li storage performance and intriguing application as nanothermometer. The versatility of the molten salt electrolysis of CO2 in Ca-based molten salts for template-free generation of advanced carbon materials is evidenced by the successful generation of pure CNT, Zn@CNT and Fe@CNT.

5.
Diabetol Metab Syndr ; 15(1): 136, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37349808

RESUMEN

BACKGROUND: The evidence on the association between the triglyceride glucose (TyG) index and the risk of death in the general population remains controversial. This study aims to investigate the relationship between the TyG index and all-cause and cardiovascular mortality in the general population, with a focus on sex differences. METHODS: This prospective cohort study analyzed data from the National Health and Nutrition Examination Survey (1999-2002), comprising 7,851 US adults. The study employed multivariate Cox proportional hazards regression and two-segment Cox hazard regression models to evaluate the sex-specific differences in the relationship between the TyG index and all-cause and cardiovascular mortality. RESULTS: After 11,623 person-years of follow-up, there were 539 deaths, with 10.56% due to all-cause mortality and 2.87% due to cardiovascular mortality. After adjusting for multiple variables, our study found a U-shaped association of the TyG index with all-cause and cardiovascular mortality, with inflection points at 9.36 and 9.52. A significant sex difference was observed in the association between the TyG index and mortality. Below the inflection point, the relationship between the TyG index and mortality was consistent in males and females. However, above the inflection point, only males exhibited a positive association between the TyG index and all-cause mortality (adjusted hazard risk [HR], 1.62, 95% confidence interval [CI], 1.24-2.12) and cardiovascular mortality (adjusted HR, 2.28, 95% CI, 1.32-3.92). CONCLUSIONS: Our study showed a U-shaped association between the TyG index and all-cause and cardiovascular mortality in the general population. Furthermore, sex differences were observed in the association between the TyG index and mortality once it exceeded a certain threshold.

6.
Front Public Health ; 10: 1031241, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36483238

RESUMEN

Background: A substantial reduction in the number of cardiac implantable electronic device (CIED) implantation was reported in the early stages of the COVID-19 pandemic. None of the studies have yet explored changes in CIED implantation during the following pandemic. Objective: To explore changes in CIED implantation during the COVID-19 pandemic from 2020 to 2021. Methods: From 2019 to 2021, 177,263 patients undergone CIED implantation from 1,227 hospitals in China were included in the analysis. Generalized linear models measured the differences in CIED implantation in different periods. The relationship between changes in CIED implantation and COVID-19 cases was assessed by simple linear regression models. Results: Compared with the pre-COVID-19 period, the monthly CIED implantation decreased by 17.67% (95% CI: 16.62-18.72%, p < 0.001) in 2020. In 2021, the monthly number of CIED implantation increased by 15.60% (95% CI: 14.34-16.85%, p < 0.001) compared with 2020. For every 10-fold increase in the number of COVID-19 cases, the monthly number of pacemaker implantation decreased by 429 in 2021, while it decreased by 676 in 2020. The proportion of CIED implantation in secondary medical centers increased from 52.84% in 2019 to 56.77% in 2021 (p < 0.001). For every 10-fold increase in regional accumulated COVID-19 cases, the proportion of CIED implantation in secondary centers increased by 6.43% (95% CI: 0.47-12.39%, p = 0.036). Conclusion: The impact of the COVID-19 pandemic on the number of CIED implantation is diminishing in China. Improving the ability of secondary medical centers to undertake more operations may be a critical way to relieve the strain on healthcare resources during the epidemic.


Asunto(s)
COVID-19 , Pandemias , Humanos , COVID-19/epidemiología , China/epidemiología
7.
Front Public Health ; 10: 1027926, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36504945

RESUMEN

Background: The COVID-19 pandemic has significantly impacted routine cardiovascular health assessments and services. We aim to depict the temporal trend of catheter ablation (CA) and provide experience in dealing with the negative impact of the COVID-19 pandemic. Methods: Data on CA between January 2019, and December 2021, were extracted from the National Center for Cardiovascular Quality Improvement platform. CA alterations from 2019 to 2021 were assessed with a generalized estimation equation. Results: A total of 347,924 patients undergoing CA were included in the final analysis. The CA decreased remarkably from 122,839 in 2019 to 100,019 (-18.58%, 95% CI: -33.40% to -3.75%, p = 0.02) in 2020, and increased slightly to 125,006 (1.81%, 95% CI: -7.01% to 3.38%, p = 0.49) in 2021. The CA experienced the maximal reduction in February 2020 (-88.78%) corresponding with the peak of monthly new COVID-19 cases and decreased by 54.32% (95%CI: -71.27% to -37.37%, p < 0.001) during the 3-month lockdown and increased firstly in June 2020 relative to 2019. Since then, the CA in 2020 remained unchanged relative to 2019 (-0.06%, 95% CI: -7.01% to 3.38%, p = 0.98). Notably, the recovery of CA in 2021 to pre-COVID-19 levels was mainly driven by the growth of CA in secondary hospitals. Although there is a slight increase (2167) in CA in 2021 relative to 2019, both the absolute number and proportion of CA in the top 50 hospitals nationwide [53,887 (43.09%) vs. 63,811 (51.95%), p < 0.001] and top three hospitals in each province [66,152 (52.73%) vs. 72,392 (59.28%), p < 0.001] still declined significantly. Conclusions: The CA experienced a substantial decline during the early phase of the COVID-19 pandemic, and then gradually returned to pre-COVID-19 levels. Notably, the growth of CA in secondary hospitals plays an important role in the overall resumption, which implies that systematic guidance of secondary hospitals with CA experience may aid in mitigating the negative impact of the COVID-19 pandemic.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Control de Enfermedades Transmisibles , Análisis Espacio-Temporal , Hospitales
8.
J Inflamm Res ; 15: 6645-6656, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36532652

RESUMEN

Background: The joint association of atrial fibrillation (AF) and statin therapy with adverse outcomes in heart failure (HF) patients with cardiac resynchronization therapy (CRT) has not been fully investigated so far. The purpose of this study was to explore the independent and joint association of AF and statin therapy with adverse outcomes. Methods: Study patients were divided into four groups according to AF status and statin use: Non-AF/Statin, Non-AF/Non-Statin, AF/Statin, and AF/Non-Statin. Multivariate Cox proportional hazards regression models were used to evaluate the independent and joint association of AF and statin therapy with poor prognosis. Results: Among 685 CRT patients, there were 180 deaths (26.5%) and 198 HF hospitalization (29.6%) during the 14 years of follow-up. AF was associated with a 46% increased risk of all-cause mortality (HR, 1.46; 95% CI, 1.03-2.07) and a 59% increased risk of HF hospitalization (HR, 1.59; 95% CI, 1.16-2.20) than those without AF. However, statin therapy failed to improve the prognosis. In the joint analysis, compared with the Non-AF/Statin group, the AF/Non-Statin group suffered a higher risk of all-cause mortality (HR, 1.75; 95% CI, 1.04-2.93) and HF hospitalization (HR, 1.76; 95% CI, 1.08-2.86). Furthermore, adding AF to the traditional risk factor model significantly improved the predictive value for death (C-statistic from 0.654 to 0.691) and HF (C-statistic from 0.613 to 0.675). Conclusion: AF was associated with poor prognosis, and statin use failed to improve the prognosis. Further analysis showed that statin therapy is ineffective in improving prognosis and fails to attenuate the adverse effects of AF.

9.
Dalton Trans ; 51(46): 17780-17786, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36349813

RESUMEN

In this work, the smashing effect of explosives innovatively led to the preparation of nanoparticles. The energetic material 3,5-dinitrobenzoic acid (DNBA) was introduced as a ligand to coordinate with silver ions and connect graphene sheets via electrostatic attraction in the sol-gel process. Owing to the thermolysis of DNBA, the pore-formation of graphene sheets, thermal reduction of Ag+ and achievement of monodisperse Ag nanoparticles were realized simultaneously. The morphology and composition of the nanocomposites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Then, the nanocomposite was used to construct a hydrogen peroxide (H2O2) sensor, which displayed excellent catalytic performance over a wide linear concentration range of 4 × 10-5 to 4 × 10-3 mM with a corresponding sensitivity of 72 µA mM-1 cm-2 and detection limit of 101.25 nM with a signal-to-noise ratio of 3.

10.
J Transl Med ; 20(1): 478, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-36266665

RESUMEN

BACKGROUND: The combined association of triglyceride-glucose (TyG) index and different systolic blood pressure (SBP) levels with all-cause and cardiovascular mortality among the general population remains unclear. METHODS: In this study, 6245 individuals were from the National Health and Nutrition Examination Survey (1999-2002). The study endpoints were all-cause and cardiovascular mortality. Multivariate Cox proportional hazards regression models were used to explore the combined association of TyG index and different SBP levels with all-cause and cardiovascular mortality. RESULTS: During a mean follow-up period of 66.8 months, a total of 284 all-cause deaths (331/100000 person-years) and 61 cardiovascular deaths (66/100000 person-years) were recorded. Multivariate Cox regression analysis revealed that the combination of low TyG index and low SBP (< 120 mmHg and < 130 mmHg) was associated with a reduced risk of all-cause and cardiovascular mortality than others. However, survival benefit was not observed in the combined group with the low TyG index and SBP < 140 mmHg. Furthermore, the mortality rate in the combined group of low TyG index and low SBP gradually increased with the elevation of SBP level. CONCLUSION: The combination of low TyG index and low SBP (< 120 mmHg and < 130 mmHg) was associated with a lower risk of all-cause and cardiovascular mortality. However, no survival benefit was observed in the combined group of low TyG index and SBP < 140 mmHg.


Asunto(s)
Enfermedades Cardiovasculares , Glucosa , Humanos , Presión Sanguínea , Triglicéridos , Encuestas Nutricionales , Glucemia/análisis , Factores de Riesgo , Biomarcadores , Medición de Riesgo
11.
Antimicrob Agents Chemother ; 66(6): e0221821, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35658489

RESUMEN

Liver-stage Plasmodium in humans is an early stage of malarial infection. Decoquinate (DQ) has a potent multistage antimalarial activity. However, it is practically water insoluble. In this study, the hot-melt extrusion (HME) approach was employed to prepare solid dispersions of DQ to improve oral bioavailability. The DQ dispersions were homogeneous in an aqueous suspension that contained most DQ (>90%) in the aqueous phase. Soluplus, a solubilizer, was found compatible with DQ in forming nanoparticle formulations during the HME process. Another excipient HPMC AS-126 was also proven to be suitable for making DQ nanoparticles through HME. Particle size and antimalarial activity of HME DQ suspensions remained almost unchanged after storage at 4°C for over a year. HME DQ was highly effective at inhibiting Plasmodium infection in vitro at both the liver stage and blood stage. HME DQ at 3 mg/kg by oral administration effectively prevented Plasmodium infection in mice inoculated with Plasmodium berghei sporozoites. Orally administered HME DQ at 2,000 mg/kg to mice showed no obvious adverse effects. HME DQ at 20 mg/kg orally administered to rats displayed characteristic distributions of DQ in the blood with most DQ in the blood cells, revealing the permeability of HME DQ into the cells in relation to its antimalarial activity. The DQ dispersions may be further developed as an oral formulation targeting Plasmodium infection at the liver stage.


Asunto(s)
Antimaláricos , Decoquinato , Malaria , Animales , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Decoquinato/farmacología , Composición de Medicamentos , Calor , Hígado , Malaria/tratamiento farmacológico , Ratones , Plasmodium berghei , Ratas , Solubilidad
12.
Malar J ; 21(1): 24, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35073922

RESUMEN

BACKGROUND: Severe malaria caused by Plasmodium falciparum leads to most malaria-related deaths globally. Decoquinate (DQ) displays strong activity against multistage infection by Plasmodium parasites. However, the development of DQ as an oral dosage form for the treatment of malaria at the blood stage has not been successful. In this study, liposome formulations of DQ were created for intravenous (IV) injection to suppress Plasmodium berghei, a parasite that causes severe malaria in mice. METHODS: DQ liposomes were prepared by conventional ethanol injection method with slight modifications and encapsulation efficiency evaluated by the well-established centrifugation method. Potency of the DQ liposomes against P. falciparum was assessed in vitro using freshly isolated human red blood cells. The efficacy of the DQ liposomes was examined in the mouse model of severe malaria. RESULTS: The DQ liposomes were around 150 nm in size and had the encapsulation efficiency rates > 95%. The freshly prepared and lyophilized liposomes were stable after storage at - 20 °C for 6 months. The liposomes were shown to have excellent activity against P. falciparum in vitro with DQ IC50 0.91 ± 0.05 nM for 3D7 (chloroquine sensitive strain) and DQ IC50 1.33 ± 0.14 nM for Dd2 (multidrug resistant strain), which were 18- and 14-fold more potent than artemisinin, respectively. Mice did not have any signs of toxicity after receiving high dose of the liposomes (DQ 500 mg/kg per mouse) by IV injection. In the mouse model of severe malaria, the liposomes had impressive efficacy against P. berghei with DQ ED50 of 0.720 mg/kg. CONCLUSION: The DQ liposomes prepared in this study were stable for long term storage and safe for IV injection in mammalian animals. The newly created liposome formulations had excellent activity against Plasmodium infection at the blood-stage, which encourages their application in the treatment of severe malaria.


Asunto(s)
Antimaláricos/farmacología , Decoquinato/farmacología , Eritrocitos/efectos de los fármacos , Liposomas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Animales , Animales no Consanguíneos , Eritrocitos/parasitología , Femenino , Humanos , Masculino , Ratones
13.
Med Sci Monit ; 27: e930909, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34873140

RESUMEN

BACKGROUND Fine particulate matter (PM2.5) is the air pollutant that most threatens global public health. The purpose of this study was to observe the inflammatory and oxidative stress injury of multiple organs induced by PM2.5 in rats and to explore the tissue-protective effect of erdosteine. MATERIAL AND METHODS We randomly divided 40 male Wistar rats into a blank control group, a saline group, a PM2.5 exposure group, and an erdosteine intervention group. We assessed changes in organs tissue homogenate and biomarkers of inflammation and oxidative stress in serum and bronchoalveolar lavage fluid (BALF). RESULTS (1) The expressions of IL-6, IL-1ß, TNF-alpha, 8-OHdG, 4-HNE, and PCC in serum and BALF of the PM2.5 exposure group increased, but decreased after treatment with erdosteine, suggesting that erdosteine treatment attenuates inflammatory and oxidative stress injury. (2) The expression of γ-GCS in serum and lungs in the PM2.5 exposure group increased, but did not change significantly after treatment with erdosteine. This suggests that PM2.5 upregulates the level of γ-GCS, while erdosteine does not affect this protective response. (3) The expression of T-AOC in serum, lungs, spleens, and kidneys of the PM2.5 exposure group decreased, but increased after treatment with erdosteine. Our results suggest that PM2.5 can cause imbalance of oxidation/anti-oxidation in multiple organs, and erdosteine can alleviate this imbalance. CONCLUSIONS PM2.5 exposure can lead to inflammatory and oxidative stress damage in serum and organ tissues of rats. Erdosteine may be an effective anti-inflammatory and antioxidant that can reduce this injury.


Asunto(s)
Inflamación/prevención & control , Riñón/efectos de los fármacos , Lesión Pulmonar/prevención & control , Estrés Oxidativo/efectos de los fármacos , Material Particulado/efectos adversos , Bazo/efectos de los fármacos , Tioglicolatos/farmacología , Tiofenos/farmacología , Animales , Antioxidantes/farmacología , Biomarcadores/metabolismo , Líquido del Lavado Bronquioalveolar , Modelos Animales de Enfermedad , Expectorantes , Masculino , Ratas , Ratas Wistar
14.
Front Cardiovasc Med ; 8: 648910, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33981734

RESUMEN

Aims: To evaluate whether low level left vagus nerve stimulation (LLVNS) in early stage of myocardial infarction (MI) could effectively prevent ventricular arrhythmias (VAs) and protect cardiac function, and explore the underlying mechanisms. Methods and Results: After undergoing implantable cardioverter defibrillators (ICD) and left cervical vagal stimulators implantation and MI creation, 16 dogs were randomly divided into three groups: the MI (n = 6), MI+LLVNS (n = 5), and sham operation (n = 5) groups. LLVNS was performed for 3 weeks. VAs, the left ventricular function, the density of the nerve fibers in the infarction area and gene expression profiles were analyzed. Compared with the MI group, dogs in the MI+LLVNS group had a lower VAs incidence (p < 0.05) and better left ventricular function. LLVNS significantly inhibited excessive sympathetic nerve sprouting with the evidences of decreased density of TH, GAP43 and NF positive nerves (p < 0.05). The gene expression profiling found a total of 206 genes differentially expressed between MI+LLVNS and MI dogs, mainly involved in cardiac tissue remodeling, cardiac neural remodeling, immune response and apoptosis. These genes, including 55 up-regulated genes and 151 down-regulated genes, showed more protective expressions under LLVNS. Conclusions: This study suggests that LLVNS was delivered without altering heart rate, contributing to reduced incidences of VAs and improved left ventricular function. The potential mechanisms included suppressing cardiac neuronal sprouting, inhibiting excessive sympathetic nerve sprouting and subduing pro-inflammatory responses by regulating gene expressions from a canine experimental study.

15.
Talanta ; 225: 122084, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33592796

RESUMEN

In this paper, a cysteine-functionalized zwitterionic stationary phase (Cys-silica) was prepared based on the "thiol-ene" click chemistry between cysteine and vinyl-functionalized silica, and was further modified with bromoethane, 1-bromooctane and 1-bromooctadecane, respectively, to obtain a series of quaternary ammoniation-functionalized stationary phases (Cys-silica-Cn, n = 2, 8 and 18). These zwitterionic stationary phases were regarded as reversed-phase/ion-exchange (RP/IEC) mixed-mode chromatography (MMC) stationary phases for protein separation. The retention behaviors of proteins on these zwitterionic stationary phases were carefully investigated. The results indicated that the retentions of acidic and basic proteins on these zwitterinonic stationary phases were significantly influenced by the acetonitrile and salt concentrations, pH of mobile phase as well as the hydrophobicity of the ligand. The separation selectivity of proteins on these zwitterionic stationary phases strongly depended on the pH value of mobile phase. The baseline separation of 6 kinds of basic proteins can be achieved at pH 8.0 using Cys-silica-C2 or Cys-silica-C8 column, and 5 kinds of acidic proteins can also be separated completely at pH 4.0 with Cys-silica-C2 column. Moreover, owing to the quaternary ammoniation-functionalization on Cys-silica by using appropriately hydrophobic bromoalkanes, the selectivity and separation efficiency of proteins can be enhanced greatly. As a result, the acidic and basic proteins can be separated completely step by step from the complex sample by adjusting pH of mobile phase using a single Cys-silica-C2 column, which illustrates that the cysteine-functionalized zwitterionic stationary phase has a great potential for protein separation.


Asunto(s)
Química Clic , Cisteína , Cromatografía por Intercambio Iónico , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Dióxido de Silicio
16.
J Interv Card Electrophysiol ; 61(3): 545-550, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32808082

RESUMEN

PURPOSE: Magnetic resonance imaging (MRI) at 3.0 T is becoming more common, but there is a lack of sufficient evidence on the safety of a 3.0 T scan in patients with pacemakers. This study aimed to investigate the safety and practical concerns of 3.0 T scans for patients with MR-conditional pacemakers. METHODS: Twenty consecutive patients were enrolled. A standardized protocol was developed by cardiologists, pacemaker engineers, and radiologists. Pacemaker interrogation was performed immediately before and after the scan. Scan-related adverse events were documented, and imaging quality was graded as level 1 to 4 by radiologists. RESULTS: Twenty-three MRI scans of different body regions (brain = 13, lumbar spine = 4, cervical spine = 2, and heart = 4) were performed, and the average time of a scan was 25 ± 11 min. No significant changes in sensing amplitude (atrial 3.1 ± 1.1 mV vs. 2.9 ± 1.2 mV, P = 0.71; ventricular 9.3 ± 3.5 mV vs. 10.2 ± 3.4 mV, P = 0.46), lead impedances (atrial 647 ± 146 Ω vs. 627 ± 151 Ω, P = 0.7; ventricular: 780 ± 247 Ω vs.711 ± 226 Ω, P = 0.36), or pacing threshold (atrial 0.6 ± 0.2 V/0.4 ms vs. 0.6 ± 0.2 V/0.4 ms, P = 0.71; ventricular 0.7 ± 0.3 V/0.4 ms vs. 0.7 ± 0.2 V/0.4 ms, P = 0.85) were observed pre- and postscan. No adverse events were detected. Image quality review showed grade 1 quality in 16 patients and grade 2 quality in 4 patients with artifacts of pulse generators and leads in cardiac MRI scan and no impact on diagnostic value. CONCLUSION: Our initial data indicated that 3.0 T scanning might be feasible under a standardized protocol with good diagnostic imaging quality irrespective of body region in patients with MR-conditional pacemakers.


Asunto(s)
Marcapaso Artificial , Artefactos , Seguridad de Equipos , Ventrículos Cardíacos , Humanos , Imagen por Resonancia Magnética
17.
Ann Noninvasive Electrocardiol ; 26(2): e12814, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33368864

RESUMEN

BACKGROUND: Ventricular arrhythmia is a leading cause of cardiac death among patients with post-infarction left ventricular aneurysm (PI-LVA). The effect of coronary revascularization in PI-LVA patients with ventricular tachyarrhythmia remains unknown. This study aims to investigate the impact of revascularization therapy on clinical outcomes in these patients. METHODS: A total of 238 PI-LVA patients were enrolled, and 59 patients were presented with sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Patients were classified into 4 groups by treatment strategies (medical or revascularization) and the presence of VT/VF: group 1 (n = 57): VT/VF- and revascularization-; group 2 (n = 122): VT/VF- and revascularization+; group 3 (n = 34): VT/VF+ and revascularization+; and group 4 (n = 25): VT/VF+ and revascularization-. The clinical outcomes were compared, and the primary endpoint was cardiac death or heart transplantation. RESULTS: Patients were followed up for 45 ± 16 months, and 41 patients (17.2%) reached the primary endpoint. Kaplan-Meier analysis showed that in VT/VF- patients, revascularization associated with higher cardiac survival compared with medical therapy (log-rank p = .002), but in VT/VF+ patients, revascularization did not predict better cardiac outcome (log-rank p = .901). Cox regression analysis revealed PET-EF (HR 4.41, 95% CI: 1.72-11.36, p = .002) and moderate/severe mitral regurgitation (HR 2.32, 95% CI: 1.02-5.30, p = .046) as independent predictors of adverse cardiac outcome in patients with VT/VF. CONCLUSION: PI-LVA patients with VT/VF are at high risk of adverse cardiac outcome, and coronary revascularization does not mitigate this risk, although revascularization was associated with higher cardiac survival in PI-LVA patients without VT/VF.


Asunto(s)
Puente de Arteria Coronaria/métodos , Aneurisma Cardíaco/cirugía , Infarto del Miocardio/complicaciones , Intervención Coronaria Percutánea/métodos , Taquicardia Ventricular/cirugía , Femenino , Estudios de Seguimiento , Aneurisma Cardíaco/etiología , Aneurisma Cardíaco/fisiopatología , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Taquicardia Ventricular/etiología , Taquicardia Ventricular/fisiopatología
18.
JACC Clin Electrophysiol ; 6(10): 1291-1299, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33092757

RESUMEN

OBJECTIVE: The aim of this study was to assess pacing and electrophysiological parameters, as well as short-term outcomes, among patients undergoing left bundle branch pacing (LBBP) or His bundle pacing (HBP). BACKGROUND: There are limited data directly comparing different conduction system pacing modalities. METHODS: Consecutive patients undergoing de novo conduction system pacing for bradycardia indications were evaluated. Procedural and fluoroscopic times and pacing characteristics were compared between groups at implantation and at 3-month follow-up. RESULTS: This study included 251 subjects. HBP was successful in 109 (87.2%) of 125 patients, compared with 115 (91.3%) of 126 for LBBP. The mean procedure time (78 ± 36 min vs. 54 ± 24 min, p < 0.001) and fluoroscopy duration (12 ± 5 min vs. 5 ± 2.8 min, p < 0.001) were significantly longer for HBP compared with LBBP. The paced QRS duration (113.7 ± 24.4 ms vs. 114.1 ± 11.2 ms) were similar between groups (p = 0.87). Capture threshold was significantly lower (1.3 ± 0.6 V/1.0 ms vs. 0.6 ± 0.2 V/0.4 ms, p < 0.001), whereas R-wave amplitude was significantly higher (2.8 ± 3.0 mV vs. 12.5 ± 9.0 mV, p < 0.001) with LBBP compared with HBP at implantation. During follow-up, a capture threshold >3.0 V occurred in 8 HBP patients versus 0 LBBP patients (p = 0.003). CONCLUSIONS: LBBP has similar paced QRS durations and success rates, but shorter procedure and fluoroscopy durations, as well as better pacing parameters compared with HBP. Further prospective study is needed to compare long-term outcomes, safety, and pacing stability with these 2 conduction system pacing modalities.


Asunto(s)
Bradicardia , Fascículo Atrioventricular , Bradicardia/terapia , Estimulación Cardíaca Artificial , Electrocardiografía , Humanos , Estudios Prospectivos
19.
Nanomedicine ; 29: 102265, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32668297

RESUMEN

Photodynamic therapy (PDT) provides a novel sight for non-invasive tumor ablation, which, however, is still limited by low converting efficiency and short life-time of produced singlet oxygen. In this work, a bioresponsive lanthanide-based nanomedicine, FeOOH-coated and toluidine blue (TB)-loaded NaLuF4:Yb,Er,Tm@NaLuF4, is constructed for tumor microenvironment-activated photodynamic therapy with triple-collaborative enhancing strategy. In response to intratumoral reducibility and acidity, coated FeOOH decomposes, eliminating reduced glutathione (GSH) and up-regulating intratumoral oxidative stress to enhance PDT. Besides, Fe2+ is also released from this redox process, which can improve intratumoral dissolved O2 for PDT by catalytic decomposition of H2O2. Lastly, quenched upconversion luminescence of lanthanide-doped nanoparticles also recovers, which allows more efficient energy transfer to TB and hence improves PDT efficiency. By the above triple-collaborative strategy, highly efficient photodynamic tumor ablation is performed in vivo. This work proposes a rigorous method to elevate photodynamic therapeutic efficiency.


Asunto(s)
Nanopartículas/química , Neoplasias/tratamiento farmacológico , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Línea Celular Tumoral , Diagnóstico por Imagen/métodos , Humanos , Peróxido de Hidrógeno/química , Elementos de la Serie de los Lantanoides/química , Elementos de la Serie de los Lantanoides/farmacología , Luminiscencia , Nanomedicina/métodos , Neoplasias/patología , Fármacos Fotosensibilizantes/química , Oxígeno Singlete/química
20.
Pacing Clin Electrophysiol ; 43(8): 781-790, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32524648

RESUMEN

AIM: To assess the electrocardiogram patterns of paced QRS narrowing after successful left bundle branch area pacing (LBBAP) and echocardiographic measurements in patients with bradycardia and bundle branch block (BBB). METHODS: We prospectively enrolled 55 consecutive bradycardia patients with BBB and left ventricular ejection fraction ≥40% who had attempted LBBAP. Successful LBBAP was defined as paced QRS morphology of a right BBB (RBBB) pattern in lead V1 and a recording of abruptly shortened and then constant stimulus to peak left ventricular activation time with high and low output. Pacing characteristics and echocardiographic measurements were evaluated perioperatively and at 6-month follow-up. RESULTS: The success rate of LBBAP was 83.6% in patients with BBB, and median cumulative X-ray dose-area product was 100.5 µGym2 (60.0, 179.3). LBBAP was successful in 19 of 26 patients with left BBB (LBBB) (73.1%) and in 27 of 29 patients with RBBB (93.1%). The QRS duration (QRSd) was significantly shortened in patients with LBBB (QRSd 169.4 ± 22.6 to 119.6 ± 9.5 ms), and five forms of QRSd narrowing were observed in patients with RBBB with the mean QRSd shortened from 143.1 ± 16.6 ms to 119.5 ± 11.7 ms. The thresholds for narrowing of QRSd were higher in RBBB than LBBB (1.74 ± 0.36 V/0.4 ms vs 0.79 ± 0.17 V/0.4 ms, P < .001). During the 6-month follow-up, both left and right ventricular synchronies were improved, and narrow QRSd persisted in patients with BBB. CONCLUSION: In most bradycardia patients, RBBB could be completely or partially narrowed by LBBAP at different pacing models in addition to the correction of LBBB with LBBAP.


Asunto(s)
Bradicardia/fisiopatología , Bradicardia/terapia , Bloqueo de Rama/fisiopatología , Bloqueo de Rama/terapia , Electrocardiografía , Estimulación Cardíaca Artificial , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
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