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1.
J Invasive Cardiol ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38754082

RESUMO

The combined procedure of catheter ablation and percutaneous left atrial appendage occlusion for patients with atrial fibrillation has been shown to be safe and feasible using radiofrequency energy or cryoballoon.

2.
ACS Appl Mater Interfaces ; 16(13): 16175-16185, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38509690

RESUMO

Zinc-ion batteries (ZIBs) are promising energy storage devices with safe, nonflammable electrolytes and abundant, low-cost electrode materials. Their practical applications are hampered by various water-related undesirable reactions, such as the hydrogen evolution reaction (HER), corrosion of zinc metal, and water-induced decay of cathode materials. Polymer hydrogel electrolytes were used to control these reactions. However, salt, water, and polymeric backbones intervene in polymer hydrogels, and currently, there are no systematic studies on how salt and water concentrations synergistically affect polymer hydrogels' electrochemical performance. Here, we used an in situ polymerization method to synthesize polyacrylamide (PAM) hydrogels with varied Zn(ClO4)2 (0.5 to 2.0 mol kg-1) and water (40 to 90 wt %) concentrations. Their electrochemical performances in Zn||Ti half-cells, Zn||Zn symmetrical cells, and Zn||V2O5 full cells have been comprehensively evaluated. Although the ionic conductivity of electrolytes increases with the salt concentration, a high salt concentration of 2.0 mol kg-1 with more Zn2+ solvated H2O would induce more severe HER and Zn corrosion at the electrolyte/electrode interfaces. A narrow window of the water concentration at 70-80 wt % is optimal to balance needs for achieving a high ionic conductivity and restricting water-related undesirable reactions. The chemically more active water counts roughly 64.1-73.1 wt % of the total water in electrolytes. PAM hydrogel electrolyte with 1.0 mol kg-1 Zn(ClO4)2 and 80 wt % water enables 1200 h of stable cycling in a Zn||Zn symmetric cell and 99.24% of Coulombic efficiency in a Zn||Ti half-cell. Due to the water-induced decay of V2O5, the electrolyte with 70 wt % water delivers the best performance in a Zn||V2O5 full cell, which can retain 73.7% of its initial capacity after 400 charge/discharge cycles. Our results show that achieving precise control of salt and water concentrations of hydrogel electrolytes in their optimal windows to reduce the fraction of chemically more active water while retaining high ionic conductivity is essential to enabling high-performance ZIBs.

3.
Int Med Case Rep J ; 16: 239-244, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37038550

RESUMO

Purpose: To report a case of misdiagnosed choroidal hemangioma, initially treated as central serous retinopathy (CSR) complicated by choroidal neovascularization (CNV), and to improve the proper identification of this disorder. Observations: Fundus images revealed a subtle, elevated choroidal lesion with an associated exudative detachment and choroidal vascular lesion on indocyanine green (ICG) angiography. Combined treatment with photodynamic therapy (PDT) and anti-VEGF therapy led to resolution of fluid and improvement in VA from 20/50 to 20/25. Conclusion: It is critical to understand the clinical features of choroidal hemangiomas and their physical presentation on retinal testing to diagnose and treat them in a timely and appropriate manner.

4.
J Hazard Mater ; 437: 129328, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35716562

RESUMO

Direct catalytic decomposition of methane (CDM) has been studied as a possible emission-free hydrogen production route for over 100 years. However, the high cost of catalyst regeneration limits its practical applications. Here, we demonstrate that the solid by-product from CDM using Fe ore catalysts comprising carbon nano onions encapsulated with magnetic Fe cores (Fe@C) can serve as efficient and recyclable Fenton catalysts for pollutant degradation. Fe@C/H2O2 has better performance than FeSO4/H2O2 at similar Fe concentrations and can be used to decompose various pollutants. Mechanistic studies reveal that graphitic carbon layers and encapsulated Fe0 contribute to their high catalytic activity. Further, Fe@C can be easily recovered from an aqueous solution and reused due to the encapsulated magnetic Fe particles. Over three reused cycles, Fe@C/H2O2 only yields 1/8 of Fe sludges compared to FeSO4/H2O2, significantly reducing Fe sludge treatment costs. Overall, Fe@C demonstrates excellent application potentials in water and wastewater treatment, making H2 production via CDM economically more viable.


Assuntos
Poluentes Ambientais , Ferro , Carbono , Catálise , Peróxido de Hidrogênio , Metano , Oxirredução
6.
Int J Geriatr Psychiatry ; 34(9): 1287-1293, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29023987

RESUMO

INTRODUCTION: Neuropsychiatric symptoms (NPS) are common at all stages of Alzheimer disease (AD). Delusions in AD are associated with negative clinical consequences and may signal rapid disease progression. Hence, we sought to determine the prevalence of delusions in drug-naïve (no cholinesterase inhibitor or neuroleptic medications) AD patients. METHODS: In this meta-analysis, a search of the EMBASE, MEDLINE, and PsycINFO databases was performed. We selected studies reporting delusion prevalence measured by the Neuropsychiatric Inventory (NPI) in drug-naïve AD patients. An aggregate delusion event rate with 95% confidence interval (CI) was calculated. The I2 statistic was used to assess the magnitude of between-study heterogeneity. Single variable meta-regressions allowed examination of the effect of moderating factors and heterogeneity. Quantitative measures were used to appraise for publication bias. RESULTS: We identified 6 studies with 591 participants allowing calculation of the aggregate delusional prevalence rate. Irrespective of dementia severity, the aggregate event rate for delusions was 29.1% (95% CI: 20-41%; I2  = 84.59). No publication bias was observed. CONCLUSION: This meta-analysis calculates a 29.1% prevalence rate of delusions in AD patients. There is a trend towards increasing delusion prevalence in concordance with increasing severity of dementia. Given delusions are associated with poorer outcomes, the obtained prevalence should motivate clinicians to screen carefully for delusions. Current literature limitations warrant future studies, with sub-analyses on dementia severity, and other neurobiological factors known to influence the presence of delusions.


Assuntos
Doença de Alzheimer/psicologia , Delusões/epidemiologia , Humanos , Prevalência
7.
Angew Chem Int Ed Engl ; 51(26): 6456-9, 2012 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-22639391

RESUMO

New sensation: A resistance-based biosensor uses gold-coated magnetic nanoparticles (Au@MNPs) functionalized with the antibiotic enrofloxin (see picture; purple), which bind to anti-enrofloxin as analyte (blue). The Au@MNPs can be magnetically assembled between electrodes, and the measured resistance R is a function of analyte concentration.


Assuntos
Técnicas Biossensoriais/métodos , Ouro/química , Nanopartículas Metálicas/química , Compostos Orgânicos/análise , Modelos Moleculares
8.
Chem Commun (Camb) ; 48(29): 3503-5, 2012 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-22389188

RESUMO

Herein, we demonstrate the use of modified gold-coated magnetic nanoparticles as 'dispersible electrodes' which act as selective capture vehicles for electrochemical detection of prostate-specific antigen (PSA). A key advantage of this system is the ability to quantify non-electrochemical active analytes such as proteins with unprecedented detection limits and fast response times.


Assuntos
Técnicas Biossensoriais , Óxido Ferroso-Férrico/química , Ouro/química , Nanopartículas/química , Antígeno Prostático Específico/análise , Anticorpos Monoclonais/imunologia , Eletroquímica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Antígeno Prostático Específico/imunologia
9.
Arch Otolaryngol Head Neck Surg ; 137(7): 694-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21768414

RESUMO

OBJECTIVE: To correlate patient reports of olfactory dysfunction after surgical intervention for allergic fungal rhinosinusitis (AFRS) with endoscopic findings, psychophysical testing, and quality-of-life scores. DESIGN: A prospective cohort study. SETTING: A tertiary care rhinology clinic at St Paul's Hospital, Vancouver, British Columbia, Canada. PATIENTS: Eighty-one patients with AFRS seen at routine postoperative follow-up. MAIN OUTCOME MEASURES: The Sniffin' Sticks test and a visual analog scale for the perceived olfactory ability of patients with AFRS were administered, along with a 36-Item Short-Form Health Survey. An endoscopic staging score was assigned for each patient. RESULTS: Forty men and 41 women with AFRS underwent olfactory testing; 52 of these individuals completed all parts of the assessment. The mean threshold, discrimination, and identification score was 19 (hyposmic), with a significant correlation between patients' performance on the Sniffin' Sticks test and endoscopic staging, as well as their reported olfactory ability (P < .001 for all 3 tests). The mean score for the 36-Item Short-Form Health Survey was 71, but there was a poor correlation between it and the threshold, discrimination, and identification score; visual analog scale; and endoscopic scores (P > .05 for all 3 tests). CONCLUSION: All patients with AFRS should be evaluated with olfactory testing and treated according to the results.


Assuntos
Micoses/complicações , Transtornos do Olfato/etiologia , Rinite Alérgica Perene/complicações , Sinusite/complicações , Olfato , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/microbiologia , Micoses/fisiopatologia , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/fisiopatologia , Estudos Prospectivos , Rinite Alérgica Perene/microbiologia , Rinite Alérgica Perene/fisiopatologia , Índice de Gravidade de Doença , Sinusite/microbiologia , Sinusite/fisiopatologia
10.
Chem Commun (Camb) ; 46(46): 8821-3, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-20953483

RESUMO

Herein, we introduce the concept of utilizing conductive gold-coated magnetic nanoparticles as 'dispersible electrodes', which serve as the active element in the selective capture and direct electro-analytical quantification of analytes. This concept reduces response times and decreases detection limits by bringing the sensor to the analyte rather than the conventional paradigm of the analyte finding the sensor.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Cobre/química , Eletroquímica , Eletrodos , Óxido Ferroso-Férrico/química , Magnetismo , Soluções , Propriedades de Superfície
11.
Chemphyschem ; 11(13): 2807-13, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20669213

RESUMO

Physical and electrochemical properties of gold nanoparticle-based electrodes are highlighted. Polycrystalline gold electrodes are passivated by a self-assembled monolayer, then the immobilization of gold nanoparticles "switch on" the electrochemical reactivity of ruthenium. Herein, gap-mode Raman studies show that the location of the nanoparticles is on the top of the monolayer, meaning that the "switching on" cannot be attributed to a direct electrical contact between nanoparticles and the gold support. This "switching on" feature is also not affected by the size of the gold nanoparticles with a range of diameters between 4 and 67 nm. Further, the charge of the nanoparticles is investigated by grafting chemical groups onto the nanoparticles which is observed to alter the electron-transfer kinetics. The variation in rate constant however is insufficient to attribute the "switching on" phenomenon to a possible adsorption of the redox species onto the nanoparticles.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Adsorção , Eletroquímica , Eletrodos , Cinética , Oxirredução , Tamanho da Partícula , Análise Espectral Raman , Propriedades de Superfície
12.
Laryngoscope ; 120(8): 1682-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20568278

RESUMO

OBJECTIVES/HYPOTHESIS: The Messerklinger technique is an endoscopic approach to sinus surgery designed to be minimally invasive and preserve mucosa and therefore physiological function. More recently there have been advocates for more radical endoscopic approaches to the frontal sinus such as the modified Lothrop procedure. This study aims to determine the effectiveness of endoscopic frontal sinusotomy in preventing recurrent frontal sinus disease and the need for any revision frontal sinus surgery. STUDY DESIGN: Retrospective data review. METHODS: A retrospective review of the chronic rhinosinusitis database at St. Paul's Sinus Centre was performed, randomly selecting 200 patients who had undergone primary bilateral functional endoscopic sinus surgery between 2000 and 2009. Any endoscopic or radiological recurrences listed on the database were counted along with the number of cases returned to theater for revision surgery. The preoperative Lund-Mackay score was also extracted from the database. RESULTS: In the 200 patients who had undergone their primary surgery at St. Paul's Hospital, the recurrence rate of frontal sinus disease was 19%, with less than one half (8%) requiring revision surgery. The Lund-Mackay scores showed no correlation between disease severity and the incidence of recurrence (P = .35), and there was no difference between polyp and nonpolyp forms of chronic rhinosinusitis (P = .14). A comparison with 100 patients in the database who had received their primary surgery at another center showed that the revision patients had a recurrence rate of 34% and a revision rate of 21%. The patients who did not receive surgical revision were treated satisfactorily with topical medications in the outpatient clinic. CONCLUSIONS: Meticulously performed endoscopic frontal sinusotomy with computer guidance appears to be an effective minimally invasive procedure to treat chronic frontal sinusitis secondary to outflow tract obstruction. Properly performed, it is effective in dealing with the most diseased frontal sinus. It offers clear advantages in reducing complications and recurrence rates in frontal sinus disease even in revision cases.


Assuntos
Seio Frontal/cirurgia , Sinusite Frontal/cirurgia , Rinite/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otorrinolaringológicos , Reoperação , Estudos Retrospectivos , Prevenção Secundária , Cirurgia Assistida por Computador , Adulto Jovem
13.
Langmuir ; 25(18): 11121-8, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19572504

RESUMO

The influence of the length of a self-assembled monolayer (SAM) linker on the electrochemical performance of electrode-linker-gold nanoparticle molecular constructs is investigated. Electrodes were first modified with amino-1-alkanethiols of four different lengths (C=2, 6, 8, and 11). The SAM showed progressively greater blocking ability to ruthenium hexamine as the length of the alkyl chain increased to the point where no significant Faradaic peak was observed for the amino-1-undecanethiol SAM. Upon the attachment of gold nanoparticles, distinct Faradaic electrochemistry of the ruthenium hexamine was observed for all four length SAMs with the electrochemistry being similar to that observed on a bare electrode. The charge transfer resistance to this Faradaic process was observed to be insensitive to the length of the intervening SAM, indicating it is electron transfer between the redox species and the nanoparticles, rather than tunneling across the SAM, which is the rate-limiting step. Some comments on the mechanism of charge transfer are provided. When forming multilayers of the linker-nanoparticle constructs, fabricated in a stepwise manner, whenever the distal species was the SAM the Faradaic process was blocked and whenever it was the nanoparticle a distinct Faradaic process was observed. With up to five layers of linker-nanoparticles, there was little increase in charge transfer resistance and again the charge transfer resistance was insensitive to the length of the linker.

14.
Nano Lett ; 9(5): 2021-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19382766

RESUMO

Monitoring enzyme secretion in tissue culture has proved challenging because to date the activity cannot be continuously measured in situ. In this Letter, we present a solution using biopolymer loaded photonic crystals of anodized silicon. Shifts in the optical response by proteolytic degradation of the biopolymer provide label-free sensing with unprecedented low detection limits (1 pg) and calculation of kinetic parameters. The enhancement in sensitivity relative to previous photonic crystal sensors constitutes a change in the sensing paradigm because here the entire pore space is responsive to the secreted enzyme rather than just the pore walls. In situ monitoring is demonstrated by detecting secretion of matrix metalloprotease 9 from stimulated human macrophages.


Assuntos
Peptídeo Hidrolases/análise , Pontos Quânticos , Técnicas de Cultura de Células , Células Cultivadas , Humanos , Macrófagos/enzimologia , Peptídeo Hidrolases/metabolismo , Fótons
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