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1.
Artigo em Inglês | MEDLINE | ID: mdl-38714325

RESUMO

Atherosclerosis (AS) is the major cause of multiple cardiovascular diseases. In addition, the lipid accumulation of human vascular smooth muscle cells (HVSMCs) can cause the occurrence of AS. Sfrp5 was known to be downregulated in atherosclerosis; however, the detailed function of Sfrp5 in HVSMCs remains unclear. Specifically, we found that Sfrp5 expression in oxLDL-treated HVSMCs was downregulated. Sfrp5 overexpression inhibited the viability of HVSMCs induced by oxLDL. In addition, oxLDL-induced proliferation and migration in HVSMCs were abolished by Sfrp5 overexpression. Sfrp5 overexpression reduced oxLDL-caused oxidative stress, lipid accumulation, and inflammation in HVSMCs. Meanwhile, oxLDL treatment increased the expressions of Wnt5a, c-Myc, and ß-catenin in HVSMCs, while this phenomenon was rescued by Sfrp5 overexpression. Furthermore, the inhibitory effect of Sfrp5 upregulation on the viability and migration of HVSMCs was reversed by R-spondin. These results indicate that Sfrp5 overexpression could reverse oxLDL-induced lipid accumulation in HVSMCs through inactivating Wnt5a/ß-catenin signaling pathway.

2.
ACS Appl Mater Interfaces ; 16(17): 22122-22130, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38626418

RESUMO

The recent discovery of ferroelectricity in pure ZrO2 has drawn much attention, but the information storage and processing performances of ferroelectric ZrO2-based nonvolatile devices remain open for further exploration. Here, a ZrO2 (∼8 nm)-based ferroelectric capacitor using RuO2 oxide electrodes is fabricated, and the ferroelectric orthorhombic phase evolution under electric field cycling is studied. A ferroelectric remnant polarization (2Pr) of >30 µC/cm2, leakage current density of ∼2.79 × 10-8 A/cm2 at 1 MV/cm, and estimated polarization retention of >10 years are achieved. When the ferroelectric capacitor is connected with a transistor, a memory window of ∼0.8 V and eight distinct states can be obtained in such a ferroelectric field-effect transistor (FeFET). Through the conductance manipulation of the FeFET, a high object image recognition accuracy of ∼93.32% is achieved on the basis of the CIFAR-10 dataset in the convolutional neural network (CNN) simulation, which is close to the result of ∼94.20% obtained by floating-point-based CNN software. These results demonstrate the potential of ferroelectric ZrO2 devices for nonvolatile memory and artificial neural network computing.

3.
Small Methods ; : e2301419, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315088

RESUMO

The development of the proton exchange membrane water electrolyzer (PEMWE) is still limited by the prohibitive cost and scarcity of iridium (Ir)-based oxygen evolution reaction (OER) catalyst. This work presents a novel catalyst synthesized by precursor-atomization and rapid joule-heating method, successfully doping iridium atoms into polyvalent tungsten blends (W0 , W5+ , W6+ ) based on titanium substrate. The vacancy engineering of unsaturated tungsten oxide (W5+ , W6+ ) reconstructs the electronic structure of the catalyst surface, which resulting in the low-valence state iridium species, avoiding excessive oxidation of iridium and accelerating the catalytic kinetics. Meanwhile, metallic tungsten (W0 ) improves the conductivity of catalyst and guarantees the stable existence of oxygen vacancy. The TiIrWOx possesses excellent performance in acidic OER catalysis, requiring overpotential of only 181 mV to drive 10.0 mA cm-2 , and exhibiting a high mass activity of 753 A gIr -1 at an overpotential of 300 mV. The membrane electrode assembly (MEA) with TiIrWOx as anode electrocatalyst can reduce the Ir consumption amount by >60% compared to commercial IrO2 , and it can operated over 120 h at a current density of 1.0 A cm-2 .

4.
Adv Mater ; 36(15): e2211305, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38291852

RESUMO

The big data era requires ultrafast, low-power, and silicon-compatible materials and devices for information storage and processing. Here, ferroelectric tunnel junctions (FTJs) based on SiO2/Hf0.5Zr0.5O2 composite barrier and both conducting electrodes are designed and fabricated on Si substrates. The FTJ achieves the fastest write speed of 500 ps under 5 V (2 orders of magnitude faster than reported silicon-compatible FTJs) or 10 ns speed at a low voltage of 1.5 V (the lowest voltage among FTJs at similar speeds), low write current density of 1.3 × 104 A cm-2, 8 discrete states, good retention > 105 s at 85 °C, and endurance > 107. In addition, it provides a large read current (88 A cm-2) at 0.1 V, 2 orders of magnitude larger than reported FTJs. Interestingly, in FTJ-based synapses, gradually tunable conductance states (128 states) with high linearity (<1) are obtained by 10 ns pulses of <1.2 V, and a high accuracy of 91.8% in recognizing fashion product images is achieved by online neural network simulations. These results highlight that silicon-compatible HfO2-based FTJs are promising for high-performance nonvolatile memories and electrical synapses.

5.
Eur J Clin Invest ; 54(2): e14113, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37874275

RESUMO

BACKGROUND: Cataract is the leading cause of blindness around the world. Previous investigations have assessed the relationship between cataract, cataract surgery and dementia risk, but their results remain controversial. Herein, we conducted a meta-analysis to evaluate the associations between cataract, cataract surgery and the risk of dementia. METHODS: We systemically screened the literature from three electronic databases PubMed, EMBASE and CENTRAL until April 2023. The data were collected by two independent researchers. The hazard ratios (HRs) or odds ratios (ORs) from eligible studies with 95% confidence intervals (CIs) were adjusted into the risk ratios (RRs), which were pooled using the random-effects model. RESULTS: A total of nine studies with 448,140 participants reported the associations between cataract or cataract surgery and the risk of dementia were included in this meta-analysis. The outcomes of our pooled analysis indicated that cataract was associated with an increased risk of all-cause dementia (RR = 1.24, 95% CI, 1.14-1.35, p < .00001), Alzheimer's disease (RR = 1.22, 95% CI, 1.10-1.35, p = .0002) and vascular dementia (RR = 1.29, 95% CI, 1.01-1.66, p = .04). Cataract surgery is associated with a reduction of the dementia risk (RR = 0.74, 95% CI, 0.67-0.81, p < .00001). CONCLUSIONS: Current evidence from the existing studies supports that cataract is associated with an increased risk of dementia, and cataract surgery may be instrumental in reducing the risk of dementia in patients with cataract.


Assuntos
Doença de Alzheimer , Extração de Catarata , Catarata , Humanos , Extração de Catarata/efeitos adversos , Extração de Catarata/métodos , Catarata/epidemiologia , Catarata/etiologia , Doença de Alzheimer/etiologia
6.
J Colloid Interface Sci ; 658: 714-727, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38141393

RESUMO

This work developed a novel chalcopyrite (CuFeS2) incorporated catalytic ceramic membrane (CFSCM), and comprehensively evaluated the oxidation-filtration efficiency and mechanism of CFSCM/peroxymonosulfate (PMS) for organics removal and membrane fouling mitigation. Results showed that PMS activation was more efficient in the confined membrane pore structure. The CFSCM50/PMS filtration achieved almost complete removal of 4-Hydroxybenzoic acid (4-HBA) under the following conditions: pH = 6.0, CPMS = 0.5 mM, and C4-HBA = 10 mg/L. Meanwhile, the membrane showed good stability after multiple uses. During the reaction, SO4•- and •OH were generated in the CFSCM50/PMS system, and SO4•- was considered to be the dominant reactive species for pollutant removal. The roles of copper, iron, and sulfur species, as well as the possible catalytic mechanism were also clarified. Besides, the CFSCM50/PMS catalytic filtration exhibited excellent antifouling properties against NOM with reduced reversible and irreversible fouling resistances. The Extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory analysis showed an increased in repulsive energy at the membrane-foulant interface in the CFSCM50/PMS system. Membrane fouling model analysis indicated that standard blocking was the dominant fouling pattern for CFSCM50/PMS filtration. Overall, this work demonstrates an efficient catalytic filtration process for foulants removal and outlines the synergy of catalytic oxidation and interface interaction.

7.
Waste Manag ; 172: 117-126, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37913689

RESUMO

Membrane concentrated landfill leachate has been characterized by complex component and degradation resistant. In this work, a new catalytic ceramic membrane (CuCM) was developed by in-situ integrating copper oxide in the membrane and used in combination with peroxymonosulfate (PMS) for leachate concentrate treatment. The performance and key factors of the CuCM/PMS system were systematically studied. Results showed that the CuCM/PMS system experienced promising efficiency in the pH range of 3 âˆ¼ 11. The highest COD, TOC, UV254 and Color removal efficiency achieved by the CuCM-3/PMS system under the conditions of pH = 7.0 and CPMS = 10 mM, which reached up to 63.4%, 50.5%, 75.1% and 90.2%, respectively. The possible mechanism of leachate remediation was proposed and non-free radicals (Cu(Ⅲ), 1O2) played an important role in the CuCM/PMS system for leachate remediation. The fluorescence spectrum and GC-MS analysis showed that the refractory organics with a high molecular weight in the leachate concentrate were mostly oxidized into small molecules, which also alleviated the membrane fouling. In addition, the slight decrease in COD (7.4%) and TOC (9.7%) after 6 cycles revealed the good catalytic stability and reusability of CuCM-3/PMS. This work provides a feasible strategy for leachate concentrate remediation via a nonradical oxidation process.


Assuntos
Peróxidos , Poluentes Químicos da Água , Oxirredução , Cerâmica , Poluentes Químicos da Água/análise
8.
Arq. bras. oftalmol ; 86(4): 322-329, July-Sep. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447374

RESUMO

ABSTRACT Purpose: This study aimed to use computational models for simulating the movement of respiratory droplets when assessing the efficacy of standard slit-lamp shield versus a new shield designed for increased clinician comfort as well as adequate protection. Methods: Simulations were performed using the commercial software Star-CCM+. Respiratory droplets were assumed to be 100% water in volume fraction with particle diameter distribution represented by a geometric mean of 74.4 (±1.5 standard deviation) μm over a 4-min duration. The total mass of respiratory droplets expelled from patients' mouths and droplet accumulation on the manikin were measured under the following three conditions: with no slit-lamp shield, using the standard slit-lamp shield, and using our new proposed shield. Results: The total accumulated water droplet mass (kilogram) and percentage of expelled mass accumulated on the shield under the three aforementioned conditions were as follows: 5.84e-10 kg (28% of the total weight of particle emitted that settled on the manikin), 9.14e-13 kg (0.045%), and 3.19e-13 (0.015%), respectively. The standard shield could shield off 99.83% of the particles that would otherwise be deposited on the manikin, which is comparable to 99.95% for the proposed design. Conclusion: Slit-lamp shields are effective infection control tools against respiratory droplets. The proposed shield showed comparable effectiveness compared with conventional slit-lamp shields, but with potentially enhanced ergonomics for ophthalmologists during slit-lamp examinations.


RESUMO Introdução: Os oftalmologistas têm alto risco de contrair a doença do Coronavírus-19 devido à proximidade com os pacientes durante os exames com lâmpada de fenda. Usamos um modelo de computação para avaliar a eficácia das proteções para lâmpadas de fenda e propusemos uma nova proteção ergonomicamente projetada. Métodos: As simulações foram realizadas no software comercial Star-CCM +. Os aerossóis de gotículas foram considerados 100% de água em fração de volume com distribuição de diâmetro de partícula representada por uma média geométrica de 74,4 ± 1,5 (desvio padrão) μm ao longo de uma duração de quatro minutos. A massa total de gotículas de água acumulada no manequim e a massa expelida pela boca do paciente foram medidas em três condições diferentes: 1) Sem protetor de lâmpada de fenda, 2) com protetor padrão, 3) Com o novo protetor proposto. Resultados: A massa total acumulada das gotas de água (kg) e a porcentagem da massa expelida acumulada no escudo para cada uma das respectivas condições foram; 1) 5,84e-10 kg (28% do peso total da partícula emitida que assentou no manequim), 2) 9,14e-13 kg (0,045%), 3,19e-13 (0,015%). O escudo padrão foi capaz de proteger 99,83% das partículas que, de outra forma, teriam se depositado no manequim, o que é semelhante a 99,95% para o projeto proposto. Conclusão: Protetores com lâmpada de fenda são ferramentas eficazes de controle de infecção contra gotículas respiratórias. O protetor proposto mostrou eficácia comparável em comparação com os protetores de lâmpada de fenda convencionais, mas potencialmente oferece uma melhor ergonomia para oftalmologistas durante o exame de lâmpada de fenda.

9.
RSC Adv ; 13(25): 17436-17448, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37313519

RESUMO

Catalytic ceramic membranes (CMs) integrated with different metal oxides were designed and fabricated by an impregnation-sintering method. The characterization results indicated that the metal oxides (Co3O4, MnO2, Fe2O3 and CuO) were uniformly anchored around the Al2O3 particles of the membrane basal materials, which could provide a large number of active sites throughout the membrane for the activation of peroxymonosulfate (PMS). The performance of the CMs/PMS system was evaluated by filtrating a phenol solution under different operating conditions. All the four catalytic CMs showed desirable phenol removal efficiency and the performance was in order of CoCM, MnCM, FeCM and CuCM. Moreover, the low metal ion leaching and high catalytic activity even after the 6th run revealed the good stability and reusability of the catalytic CMs. Quenching experiments and electron paramagnetic resonance (EPR) measurements were conducted to discuss the mechanism of PMS activation in the CMs/PMS system. The reactive oxygen species (ROS) were supposed to be SO4˙- and 1O2 in the CoCM/PMS system, 1O2 and O2˙- in the MnCM/PMS system, SO4˙- and ·OH in the FeCM/PMS system, and SO4˙- in the CuCM/PMS system, respectively. The comparative study on the performance and mechanism of the four CMs provides a better understanding of the integrated PMS-CMs behaviors.

10.
Int J Biol Macromol ; 235: 123925, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36871682

RESUMO

Poria cocos (PC) refers to a fungal species which is also known as "Fuling" in China. For >2000 years, PC has demonstrated its therapeutic values as a kind of traditional medicine. It is believed that the various biological benefits created by PCs highly rely on the Poria cocos polysaccharide (PCP). This review recapitulates the recent progress made in PCP in four aspects: i) the methods of extraction, separation, and purification, ii) structural characterization and identification, iii) the related bioactivities and mechanism of action, and iv) structure-activity relationships. Through discussion about the objective as mentioned above, it can be found out that PCP is categorized into water-soluble polysaccharide (WPCP) and alkaline-soluble polysaccharide (APCP), which are totally different in structure and bioactivity. The structures of WPCP are multiplicity whose backbone can be (1,6)-α-galactan and (1,3)-ß-mannoglucan etc. to perform various bioactivities including anti-tumor effect, anti-depressant effect, anti-Alzheimer effect, anti-atherosclerosis effect, hepatoprotection etc. The structures of APCP are much more single with backbone of (1,3)-ß-D-glucan and the studies of activity concentrate on anti-tumor effect, anti-inflammatory effect and immunomodulation. Besides, the future opportunities of WPCP are primary structure identification. For APCP, scholars can focus on the conformation of polysaccharide and its relationship with activity.


Assuntos
Neoplasias , Poria , Wolfiporia , Antioxidantes/química , Neoplasias/tratamento farmacológico , Polissacarídeos/química , Poria/química , Água , Wolfiporia/química , Glucanos/química
11.
Vasc Med ; 28(1): 6-17, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36759934

RESUMO

BACKGROUND: Circular RNAs (circRNAs) have been implicated in the pathogenesis of atherosclerosis (AS) and the migration and proliferation of vascular smooth muscle cells (VSMCs) under oxidized low-density lipoprotein (ox-LDL). Here, we defined the exact action of human circ_0007478 in VSMC migration and proliferation induced by ox-LDL. METHODS: Human VSMCs (HVSMCs) were exposed to ox-LDL. Circ_0007478, microRNA (miR)-638, and rho-associated protein kinase 2 (ROCK2) levels were gauged by quantitative real-time PCR (qRT-PCR) and western blot. Cell viability and proliferation were assessed by MTT and EdU assays, respectively. Transwell assays were used to detect cell migration and invasion. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to evaluate the direct relationship between miR-638 and circ_0007478 or ROCK2. RESULTS: Our data indicated that circ_0007478 expression was augmented in AS serum samples and ox-LDL-treated HVSMCs. Depletion of circ_0007478 attenuated HVSMC proliferation, migration, and invasion induced by ox-LDL. Mechanistically, circ_0007478 targeted miR-638 by directly pairing to miR-638. Reduction of miR-638 reversed the effects of circ_0007478 depletion on ox-LDL-evoked proliferation, migration, and invasion in HVSMCs. ROCK2 was a direct miR-638 target and miR-638-mediated inhibition of ROCK2 relieved ox-LDL-evoked HVSMC proliferation, migration, and invasion. Furthermore, circ_0007478 was identified as a competing endogenous RNA (ceRNA) for miR-638 to modulate ROCK2 expression. CONCLUSION: Our present study establishes an undescribed ceRNA regulatory network, in which circ_0007478 targets miR-638 to upregulate ROCK2, thereby contributing to ox-LDL-induced proliferation and migration in HVSMCs.


Assuntos
Aterosclerose , MicroRNAs , Humanos , Músculo Liso Vascular , Aterosclerose/genética , Movimento Celular , Lipoproteínas LDL/farmacologia , Proliferação de Células , MicroRNAs/genética , Apoptose , Células Cultivadas , Miócitos de Músculo Liso , Quinases Associadas a rho/genética
12.
DNA Cell Biol ; 42(2): 97-104, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36730754

RESUMO

To investigate the effect of paired box protein 5 (PAX5)/integrin subunit alpha X (ITGAX) in atherosclerosis (AS). AS model was established using ApoE-/- mice (C57BL/6). Human vascular smooth muscle cells (HVSMCs) were stimulated with ox-LDL. Quantitative reverse transcription polymerase chain reaction and Western blotting were used to detect the expression levels of genes and proteins. Reporter constructs and luciferase assays were used to investigate the role of ITGAX and PAX5. Cells proliferation and inflammation factors were detected. The results presented that aortic plaque area, lipid content, serum triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels were significantly increased in the high-fat diet group (p < 0.05). ITGAX was upregulated in atherosclerotic tissues. In addition, ox-LDL treatment induced HVSMCs proliferation, migration, and invasion. Reporter constructs and luciferase assays indicated ITGAX interaction with PAX5. Furthermore, siITGAX and siPAX5 cotransfection restored the rate of HVSMCs in G1 and S and G2/M phases, decreased the content of tumor necrosis factor-alpha (TNF-ɑ), interleukin (IL)-6, and IL-8 (p < 0.05). Interestingly, siITGAX and siPAX5 cotransfection also decreased the expression levels of TNF-α, TNF-R1, TNF-R2, CD19, and CD86 (p < 0.05). Our results suggest that ITGAX may be a potential therapeutic target for AS.


Assuntos
Aterosclerose , Fator de Necrose Tumoral alfa , Animais , Humanos , Camundongos , Aterosclerose/metabolismo , Diferenciação Celular , Colesterol/metabolismo , Interleucina-6 , Lipoproteínas LDL/farmacologia , Lipoproteínas LDL/metabolismo , Camundongos Endogâmicos C57BL , Fator de Transcrição PAX5/metabolismo , Transdução de Sinais
13.
ACS Appl Mater Interfaces ; 15(4): 5058-5070, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36655932

RESUMO

The spatial structure regulation of catalysts could optimize the reaction pathway and enhance the mass transfer kinetics, which might realize the efficient and low-consumption removal of pollutants in Fenton-like technology. In this study, N,N-dimethylformamide (DMF) intercalation was used to adjust the interlayer spacing of FeOCl from 7.90 to 11.84 Å by a simple and rapid intercalation method, thereby enhancing the mass transfer kinetics and altering the catalytic pathway. The removal rate of BPA in the DMF-FeOCl/PS system increased by 8.78 times, showing good resistance to complex water environments (such as pH, humic acid, and anions), especially in 5 g/L high-salt wastewater. The direct electron transfer processes between Fe(IV) and pollutants mediated by interlayer Fe sites generate phenoxy radicals, and the polymerization processes occur, achieving efficient removal of pollutants and low CO2 emissions. This study provides new insight into the efficient and low-carbon treatment of high-salt wastewater.

14.
Water Res ; 231: 119631, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36682234

RESUMO

Fenton-like reactions is attractive for environmental pollutant control, but there is an urgent need to improve the utilisation of hydroxyl radicals (·OH) in practical applications. Here, for the first time, FeOCl is encapsulated within a Metal Organic Framework (MOF) (Materials of Institut Lavoisier-101 (MIL-101(Fe))) as a yolk-shell reactor (FeOCl-MOF) by in situ growth. The interaction between FeOCl and the MOF not only increases the electron density of FeOCl, but also shifts down the d-band centre. The increase of electron density could promote the efficient conversion of H2O2 to ·OH catalysed by FeOCl. And the shift of the d-band centre to the lower energy level facilitates the desorption of ·OH. Experimental and theoretical calculations showed that the high catalytic performance was attributed to the unique yolk-shell structure that concentrates the catalytic and adsorption sites in a confinement space, as well as the improved electron density and d-band centre for efficient generation, rapid desorption and utilized nearby of ·OH. Which is utilized nearby by the organic pollutants adsorbed by the surface MOF, thus greatly improving the effective conversion of H2O2 and the ·OH utilisation (from 25.5% (Fe2+/H2O2) to 77.1% (FeOCl-MOF/H2O2)). In addition, a catalytic reactor was constructed to achieve continuous efficient treatment of organic pollutants. This work provides a Fenton-like microreactor for efficient generation, rapid desorption, and nearby utilization of ·OH to improve future technologies for deep water purification in complex environments.


Assuntos
Poluentes Ambientais , Estruturas Metalorgânicas , Espécies Reativas de Oxigênio , Estruturas Metalorgânicas/química , Peróxido de Hidrogênio/química , Radical Hidroxila/química
15.
Environ Res ; 222: 115322, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36693467

RESUMO

The presence of antibiotics in water bodies seriously threatens the ecosystem and human health. Advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS), an effective method to remove antibiotics, have a bottleneck problem that the low oxidant utilization is attributed to the hindered electron transfer between metal oxides and peroxides. Here, CuO with rich oxygen vacancies (OVs), MSCuO-300, was synthesized to efficiently degrade tetracycline hydrochloride (TTCH) (k = 0.095 min-1). The dominant role of direct adsorption and activation of OVs and its regulated Cu-O, rather than surface hydroxyl adsorption, mediated a short-range catalytic pathway. The shortened catalytic pathway between active sites and PMS accelerated the charge transfer at the interface, which promoted PMS activation. Compared with CuxO-500 and Commercial CuO, the activation rate of PMS was increased by 11.97, and 12.64 times, respectively. OVs contributed to the production of 1O2 and O2•-, the main active species. In addition, MSCuO-300/PMS showed excellent adaptability to real water parameters, such as pH (3-11), anions, and continuous reactor maintained for 168 h. This study provides a successful case for the purification of antibiotic-containing wastewater in the design of efficient catalysts by oxygen defect strategies.


Assuntos
Oxigênio , Tetraciclina , Humanos , Ecossistema , Peróxidos/química , Antibacterianos , Água
16.
J Thromb Haemost ; 21(1): 76-82, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36695399

RESUMO

BACKGROUND: Central venous catheters are prone to clotting, particularly in patients with cancer. Although low-molecular-weight heparin and direct oral anticoagulants, such as apixaban and rivaroxaban, have been evaluated for the prevention of catheter thrombosis, their efficacy remains uncertain. OBJECTIVES: Compare apixaban and rivaroxaban with enoxaparin for the prevention of catheter-induced clotting in vitro. METHODS: To address this uncertainty, we used a well-established microplate-based assay to compare the effects of enoxaparin, apixaban, and rivaroxaban on catheter-induced thrombosis and thrombin generation in human plasma. RESULTS: Consistent with our previous findings, catheter segments shortened the clotting time and promoted thrombin generation. When compared at concentrations with similar anti-factor Xa activity as enoxaparin, apixaban and rivaroxaban were >20-fold less potent than enoxaparin for the prevention of catheter-induced clotting and thrombin generation. CONCLUSION: The prevention of catheter thrombosis in patients with cancer is challenging. Clinical trials are needed to compare the efficacy of low-molecular-weight heparin with that of direct oral anticoagulants both for the prevention and treatment of catheter thrombosis.


Assuntos
Neoplasias , Trombose , Humanos , Enoxaparina/farmacologia , Enoxaparina/uso terapêutico , Rivaroxabana/uso terapêutico , Anticoagulantes/uso terapêutico , Trombina , Piridonas/farmacologia , Piridonas/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Trombose/etiologia , Trombose/prevenção & controle , Catéteres , Neoplasias/tratamento farmacológico , Inibidores do Fator Xa/uso terapêutico
17.
J Colloid Interface Sci ; 634: 231-242, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535161

RESUMO

Lower reaction speed and excessive oxidant inputs impede the removal of contaminants from water via the advanced oxidation processes based on peroxymonosulfate. Herein, we report a new confined catalysis paradigm via the hollow hetero-shell structured CN@C (H-CN@C), which permits effective decontamination through polymerization with faster reaction rates and lower oxidant dosage. The confined space structures regulated the CN and CO and electron density of the inner shell, which increased the electron transfer rate and mass transfer rate. As a result, CN in H-CN@C-10 reacted with peroxymonosulfate in preference to CO to generate singlet oxygen, improving the second-order reaction kinetics by 503 times. The identification of oxidation products implied that bisphenol AF could effectively remove by polymerization, which could reduce carbon dioxide emissions. These favorable properties make the nanoconfined catalytic polymerization of contaminants a remarkably promising nanocatalytic water purification technology.


Assuntos
Peróxidos , Purificação da Água , Polimerização , Peróxidos/química , Oxidantes
18.
Arq Bras Oftalmol ; 86(4): 322-329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35544928

RESUMO

PURPOSE: This study aimed to use computational models for simulating the movement of respiratory droplets when assessing the efficacy of standard slit-lamp shield versus a new shield designed for increased clinician comfort as well as adequate protection. METHODS: Simulations were performed using the commercial software Star-CCM+. Respiratory droplets were assumed to be 100% water in volume fraction with particle diameter distribution represented by a geometric mean of 74.4 (±1.5 standard deviation) µm over a 4-min duration. The total mass of respiratory droplets expelled from patients' mouths and droplet accumulation on the manikin were measured under the following three conditions: with no slit-lamp shield, using the standard slit-lamp shield, and using our new proposed shield. RESULTS: The total accumulated water droplet mass (kilogram) and percentage of expelled mass accumulated on the shield under the three aforementioned conditions were as follows: 5.84e-10 kg (28% of the total weight of particle emitted that settled on the manikin), 9.14e-13 kg (0.045%), and 3.19e-13 (0.015%), respectively. The standard shield could shield off 99.83% of the particles that would otherwise be deposited on the manikin, which is comparable to 99.95% for the proposed design. Conclusion: Slit-lamp shields are effective infection control tools against respiratory droplets. The proposed shield showed comparable effectiveness compared with conventional slit-lamp shields, but with potentially enhanced ergonomics for ophthalmologists during slit-lamp examinations.

19.
Front Cardiovasc Med ; 9: 1070806, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465442

RESUMO

Background: Several studies have summarized the clinical performance of direct oral anticoagulants (DOACs) in atrial fibrillation (AF) patients with mitral stenosis or aortic stenosis. The significance of this review was to provide clinicians the latest update of the clinical application of DOACs in managing this specific population. Methods: Literatures from the PubMed database up to July 2022 were screened for inclusion. Studies on the effect of DOACs in patients suffering from AF with mitral or aortic stenosis were assessed for further selection. Results: Results from four studies were gathered: the RISE MS trial, the DAVID-MS study, and two observational studies. In the Korean observational study with a 27-month follow-up duration and a sample population consisted of patients with mitral stenosis and AF, the thromboembolic events happened at a rate of 2.22%/ year in the DOAC group and 4.19%/year in the warfarin group (adjusted hazard ratio: 0.28; 95% CI: 0.18-0.45). Intracranial hemorrhage occurred at rates of 0.49% and 0.93% in the DOAC and the warfarin groups, respectively (adjusted hazard ratio: 0.53; 95% CI: 0.22-1.26). In the Danish observational study, which had a sample pool with AF patients with aortic stenosis, reported that the adjusted hazard ratios for thromboembolism and major bleeding were 1.62 (95% CI, 1.08-2.45) and 0.73 (95% CI, 0.59-0.91) for DOACs compared with warfarin during 3 years of follow-up. In the RISE-MS trial involving AF patients with mitral stenosis, there were no differences in ischemic stroke, systemic embolic events, or major bleeding between the rivaroxaban vs. warfarin groups during a 1-year follow-up as well as equal rate of increased thrombogenicity in the left atrial appendage at 6 months. The rate of silent cerebral ischemia at 12 months was higher in the warfarin group (17.6%) than that in the rivaroxaban group (13.3%). Conclusions: Current published studies supported DOACs' effectiveness in preventing thromboembolism in patients of AF with mitral or aortic stenosis. Further clinical trials could confirm these findings.

20.
ACS Appl Mater Interfaces ; 14(21): 24602-24609, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35604049

RESUMO

Ferroelectric tunnel junction (FTJ) is one promising candidate for next-generation nonvolatile data storage and neural network computing systems. In this work, the high-performance 50 nm-diameter Au/Ti/PbZr0.52Ti0.48O3 (∼3 nm, (111)-oriented)/Nb:SrTiO3 (Nb: 0.7 wt %) FTJs are achieved to demonstrate the scaling down capability of FTJ. As a nonvolatile memory, the FTJ shows eight distinct resistance states (3 bits) with a large ON/OFF ratio (>103), and these states can be switched at a fast speed of 10 ns. Intriguingly, the long-term potentiation/depression and spike timing-dependent plasticity, that is, fundamental functions of biological synapses, can be emulated in the nanoscale FTJ-based artificial synapse. A convolutional neural network (CNN) simulation is then carried out based on the experimental results, and a high recognition accuracy of ∼93.8% on fashion product images is obtained, which is very close to the result of ∼94.4% by a floating-point-based CNN software. In particular, the FTJ-based CNN simulation also exhibits robustness to input image noises. These results indicate the great potential of FTJ for high-density information storage and neural network computing.

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