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1.
Microorganisms ; 12(6)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38930468

RESUMEN

Given the recognized involvement of the gut microbiome in the development of obesity, considerable efforts are being made to discover probiotics capable of preventing and managing obesity. In this study, we report the discovery of Lactiplantibacillus plantarum GBCC_F0227, isolated from fermented food, which exhibited superior triglyceride catabolism efficacy compared to L. plantarum WCSF1. Molecular analysis showed elevated expression levels of α/ß hydrolases with lipase activity (abH04, abH08_1, abH08_2, abH11_1, and abH11_2) in L. plantarum GBCC_F0227 compared to L. plantarum WCFS1, demonstrating its enhanced lipolytic activity. In a high-fat-diet (HFD)-induced mouse obesity model, the administration of L. plantarum GBCC_F0227 mitigated weight gain, reduced blood triglycerides, and diminished fat mass. Furthermore, L. plantarum GBCC_F0227 upregulated adiponectin gene expression in adipose tissue, indicative of favorable metabolic modulation, and showed robust growth and low cytotoxicity, underscoring its industrial viability. Therefore, our findings encourage the further investigation of L. plantarum GBCC_F0227's therapeutic applications for the prevention and treatment of obesity and associated metabolic diseases.

2.
Crit Rev Anal Chem ; : 1-17, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829955

RESUMEN

Electrochemical measurements involving single nanoparticles have attracted considerable research attention. In recent years, various studies have been conducted on single-entity electrochemistry (SEE) for the in-depth analyses of catalytic reactions. Although, several electrocatalysts have been developed for H2 energy production, designing innovative electrocatalysts for this purpose remains a challenging task. Stochastic collision electrochemistry is gaining increased attention because it has led to new findings in the SEE field. Importantly, it facilitates establishing structure activity relationships for electrocatalysts by monitoring transient signals. This article reviews the recent achievements related to hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) using different electrocatalysts at the nanoscale level. In particular, it discusses the electrocatalytic activities of noble metal nanoparticles, including Ag, Au, Pt, and Pd nanoparticles, at the single-particle level. Because heterogeneity is a key factor affecting the catalytic activity of nanostructures, our work focuses on the influence of heterogeneities in catalytic materials on the OER and HER activities. These results may help to achieve a better understanding of the fundamental processes involved in the water splitting reaction.

3.
Small ; : e2400333, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528427

RESUMEN

Redox-active organic compounds gather significant attention for their potential application as electrodes in alkali ion batteries, owing to the structural versatility, environmental friendliness, and cost-effectiveness. However, their practical applications of such compounds are impeded by insufficient active sites with limited capacity, dissolution in electrolytes, and sluggish kinetics. To address these issues, a naphthol group-containing triarylamine polymer, namely poly[6,6'-(phenylazanediyl)bis(naphthol)] (poly(DNap-OH)) is rationally designed and synthesized, via oxidative coupling polymerization. It is capable of endowing favorable steric structures that facilitate fast ion diffusion, excellent chemical stability in organic electrolytes, and additional redox-active sites that enable a bipolar redox reaction. By exploiting these advantages, poly(DNap-OH) cathodes demonstrate remarkable cycling stability in both lithium-ion batteries (LIBs) and potassium-ion batteries (PIBs), showcasing enhanced specific capacity and redox reaction kinetics in comparison to the conventional poly(4-methyltriphenylamine) cathodes. Overall, this work offers insights into molecular design strategies for the development of high-performance organic cathodes in alkali-ion batteries.

4.
Microbiol Resour Announc ; 13(2): e0063523, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38206021

RESUMEN

The complete mitochondrial genome of Marphysa victori Lavesque, Daffe, Bonifácio & Hutchings, 2017, was 15,891 bp in length with a GC content of 41%, comprising 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes. The maximum-likelihood tree showed the closest relationship between M. victori and M. sanguinea.

5.
Environ Res ; 247: 118217, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38244965

RESUMEN

BACKGROUND: Recent studies have demonstrated that long-term exposure to particulate matter (PM) is associated with poor sleep quality. However, no studies have linked PM constituents, particularly heavy metals, to sleep quality. OBJECTIVE: This study investigated the association between exposure to heavy metals in PM and sleep quality. METHODS: We obtained nationwide data from the Korean Community Health Survey conducted in 2018 among adults aged 19-80 years. Sleep quality was evaluated using Pittsburgh Sleep Quality Index (PSQI). Poor sleep quality was defined as PSQI ≥5. One-year and three-month average concentrations of heavy metals (lead, manganese, cadmium, and aluminum) in PM with diameter ≤10 µm were obtained from nationwide air quality monitoring data and linked to the survey data based on individual district-level residential addresses. Logistic regression analyses were performed after adjusting for age, gender, education level, marital status, smoking status, alcohol consumption, history of hypertension, and history of diabetes mellitus. RESULTS: Of 32,050 participants, 17,082 (53.3%) reported poor sleep quality. Increases in log-transformed one-year average lead (odds ratio, 1.14; 95% confidence interval, 1.08-1.20), manganese (1.31; 1.25-1.37), cadmium (1.03; 1.00-1.05), and aluminum concentrations (1.17; 1.10-1.25) were associated with poor sleep quality. Increases in log-transformed three-month average manganese (odds ratio, 1.13; 95% confidence interval, 1.09-1.17) and aluminum concentrations (1.28; 1.21-1.35) were associated with poor sleep quality. CONCLUSION: We showed for the first time that exposure to airborne lead, manganese, cadmium, and aluminum were associated with poor sleep quality. This study may be limited by self-reported sleep quality and district-level exposure data.


Asunto(s)
Contaminantes Atmosféricos , Metales Pesados , Adulto , Humanos , Material Particulado/análisis , Manganeso/análisis , Cadmio/análisis , Calidad del Sueño , Aluminio , Exposición a Riesgos Ambientales/análisis , Metales Pesados/toxicidad , Metales Pesados/análisis , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis
6.
Anal Chem ; 95(5): 2832-2837, 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36625765

RESUMEN

Cloud point temperature (Tcp) is a thermal index used to define the phase transition of thermoresponsive polymers. In this study, we used electrochemical techniques to obtain an electrochemical cloud point temperature (Tecp) that exhibits the more accurate phase transition temperature and can replace Tcp. Thermoamperometry on an ultramicroelectrode was conducted with a poly(arylene ether sulfone) (PES10) as a model system to obtain a current-temperature (i-T) curve in real time; the Tecp of the PES10 was determined from the i-T curve. The i-T curve shows an unprecedented current decrease in the PES10 solution despite increasing temperature; on the other hand, the current increased linearly with increasing temperature in the solution without PES10. This phenomenon was analyzed by considering the characteristics of PES10 during phase transition, such as dynamic viscosity, temperature of the solution, and electrode impedance. It was confirmed that the current drops shown in the i-T curves were mainly due to the decrease of real electrode area. The comparison of Tecp and Tcp showed that both depended similarly on the concentrations of the thermoresponsive polymer and the supporting electrolyte. The results reveal that by adjusting the concentration of polymer and electrolyte in an organic solution, Tecp, as a new analytical method, can be used in electric circuit-based energy storage appliances such as Li-ion batteries and supercapacitors.

7.
Anal Chim Acta ; 1233: 340489, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36283779

RESUMEN

Excellent thermal and mechanical properties of aromatic polyimides (PIs) make them attractive materials in various fields. PIs is performed using polyamic acid (PAA) precursors due to their limited solubility. However, PAAs can be easily depolymerized by moisture and heat, which can degrade the properties of PIs. Therefore, quality control of PAAs is an important task in researches and industrial applications. Here, we propose a simple, rapid, and novel method to observe the depolymerization of PAAs. The method is based on the principle that, as the molecular weight of the polymer decreases, the solution viscosity decreases, and the viscosity of the solution can be easily and rapidly measured using electrochemistry. We accelerated depolymerization by applying heat to a PAA solution and measured the change in viscosity of the solution through cyclic voltammetry. The proposed method, which also makes it possible to determine the dynamic viscosity of a polymer solution, is presented as a model system to observe state changes in various polymers.


Asunto(s)
Derivados del Benceno , Polímeros , Polímeros/química , Derivados del Benceno/química , Electroquímica , Peso Molecular , Viscosidad
8.
Nat Commun ; 13(1): 5669, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36167830

RESUMEN

IgE is central to the development of allergic diseases, and its neutralization alleviates allergic symptoms. However, most of these antibodies are based on IgG1, which is associated with an increased risk of fragment crystallizable-mediated side effects. Moreover, omalizumab, an anti-IgE antibody approved for therapeutic use, has limited benefits for patients with high IgE levels. Here, we assess a fusion protein with extracellular domain of high affinity IgE receptor, FcεRIα, linked to a IgD/IgG4 hybrid Fc domain we term IgETRAP, to reduce the risk of IgG1 Fc-mediated side effects. IgETRAP shows enhanced IgE binding affinity compared to omalizumab. We also see an enhanced therapeutic effect of IgETRAP in food allergy models when combined with Bifidobacterium longum, which results in mast cell number and free IgE levels. The combination of IgETRAP and B. longum may therefore represent a potent treatment for allergic patients with high IgE levels.


Asunto(s)
Bifidobacterium longum , Hipersensibilidad a los Alimentos , Bifidobacterium longum/metabolismo , Suplementos Dietéticos , Hipersensibilidad a los Alimentos/terapia , Humanos , Inmunoglobulina D , Inmunoglobulina E , Inmunoglobulina G , Omalizumab/uso terapéutico , Receptores de IgE/metabolismo
9.
Nanoscale ; 14(18): 6981-6989, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35470845

RESUMEN

Single-entity analysis is an important research topic in electrochemistry. To date, electrode collisions and subsequent electrode-particle interactions have been studied for many types of nano-objects, including metals, polymers, and micelles. Here we extend this nano-object electrochemistry analysis to Pickering emulsions for the first time. The electrochemistry of Pickering emulsions is important because the internal space of a Pickering emulsion can serve as a reactor or template; this leads to myriad possible applications, all the while maintaining mechanical stability far superior to what is exhibited by conventional emulsions. This work showed that Pickering emulsions exhibit similar hydrodynamic behavior to other nano-objects, despite the complex structure involving hard nanoparticle surfactants, and the electron-transport mechanism into the internal volume of Pickering emulsions was elucidated. The Pickering emulsion electrochemistry platform developed here can be applied to electrochemical nanomaterial synthesis, surmounting the challenges faced by conventional synthetic strategies involving normal emulsions.

10.
Nanomaterials (Basel) ; 13(1)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36615957

RESUMEN

Nanoparticles are used in various fields, including fuel cells, energy conversion devices, and sensors, because of their large surface area and excellent catalytic properties. Although various methods of synthesizing nanoparticles are available, the most popular is the solution-phase reduction of metal ions. Electrodeposition is a method of reducing metal ions in solution and is widely used because of its various advantages. In this study, Ag nanoparticles with a narrow size distribution were evenly dispersed on the surface of an electrode by applying electrodeposition in an agarose hydrogel medium instead of in solution, confirming the feasibility of Ag deposition in agarose hydrogel, even at a lower reduction potential than that in solution. These results are attributed to the electrolyte effect owing to the hydrophilic backbone of the agarose hydrogel and the gel effect, which reduces unexpected convection. H2O2 was detected by using the Ag nanoparticles synthesized in agarose hydrogel, and the limit of detection for H2O2 was found to be 4.82 µM, with a dynamic range of 1-500 µM. The nanoparticle synthesis platform proposed in this study is expected to be actively used for the synthesis of other metal/nonmetal nanoparticles.

11.
Materials (Basel) ; 14(24)2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34947478

RESUMEN

We synthesized a new poly(triphenylamine), having a hyperbranched structure, and employed it in lithium-ion batteries as an organic cathode material. Two types of monomers were prepared with hydroxyl groups and nitro leaving groups, activated by a trifluoromethyl substituent, and then polymerized via the nucleophilic aromatic substitution reaction. The reactivity of the monomers differed depending on the number of hydroxyl groups and the A2B type monomer with one hydroxyl group successfully produced poly(triphenylamine). Based on thermal, optical, and electrochemical analyses, a composite poly(triphenylamine) electrode was made. The electrochemical performance investigations confirmed that the lithium-ion batteries, fabricated with the poly(triphenylamine)-based cathodes, had reasonable specific capacity values and stable cycling performance, suggesting the potential of this hyperbranched polymer in cathode materials for lithium-ion batteries.

12.
ACS Omega ; 5(25): 15709-15714, 2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32637846

RESUMEN

Oxide scales often formed on the surface of stainless steel, and it is of high interest to descale the surface oxide effectively and environment-friendly during steel smelting and engineering processing. It is generally done by treating the oxide layer under strong and harsh mixed acid (HNO3 + HF) conditions or in a strong molten salt (NaOH + NaNO3) environment at high temperatures, while the generation of very harmful and environmentally hazardous gases, such as NO x , is inevitable. A novel, simple, fast, and environment-friendly electrochemical method at ambient temperature is proposed in this research to remove the oxide scale from the stainless steel surface using an ionic liquid with a small amount of HCl. It was found that the optimized electrochemical anodization treatment in an ionic liquid environment could significantly improve the descaling efficiency at least 50 times faster than the simple passive and slow dissolution in a mixture of an ionic liquid and a concentrated acid.

13.
ACS Sens ; 5(7): 1943-1948, 2020 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-32498511

RESUMEN

This research introduces a method to directly detect serotonin in a single platelet through single-entity electrochemistry. Platelets isolated from human blood were analyzed by cyclic voltammetry and current-time measurements. When a single platelet collides with an ultramicroelectrode, serotonin inside the platelet is oxidized at the electrode surface, and an anodic current peak is consequently observed during measurement. The concentration of serotonin can be determined by integrating this peak current. In addition, this method can be used to determine the platelet concentration. Analysis of the collision frequency of platelets can provide information about the platelet concentration in the blood. As a result, platelet levels and serotonin concentrations in single platelets can be measured quickly and easily.


Asunto(s)
Plaquetas , Electroquímica , Serotonina , Electrodos , Humanos , Serotonina/análisis
14.
Biosens Bioelectron ; 151: 111999, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31999594

RESUMEN

In recent years, rapid progress in the field of single-entity electrochemistry (SEE) has opened a novel exploratory area in the field of analytical and electrochemistry. SEE is a method of studying the behavior of particles at the single particle level, which yields important information on the diffusion coefficient, individual particle size, size distribution, catalytic activity, collision frequency, and internal substances of the particles. Various types of particles have been studied through SEE. Among them, this review focuses on the results of analyzing soft particles (cells, proteins, viruses, liposomes, enzymes, vesicles, emulsion droplets, micelles, carbonaceous nanomaterials, and others). We introduce the various electrochemical techniques used in SEE and discuss important concepts and equations that must be known to apply SEE. We also introduce the results of recent research on several important soft particles. Finally, the potential applications in areas such as sensors, materials, catalysts, energy, and biomedicine, as well as the trends of related works are described. In the future, research on soft particle analysis using SEE is expected to increase rapidly, and this review is expected to be a valuable reference for researchers in the field.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Nanopartículas del Metal/química , Catálisis , Humanos , Nanoestructuras/química , Tamaño de la Partícula
15.
Genomics Inform ; 18(4): e46, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33412762

RESUMEN

We developed the BaSDAS (Barcode-Seq Data Analysis System), a GUI-based pooled knockout screening data analysis system, to facilitate the analysis of pooled knockout screen data easily and effectively by researchers with limited bioinformatics skills. The BaSDAS supports the analysis of various pooled screening libraries, including yeast, human, and mouse libraries, and provides many useful statistical and visualization functions with a user-friendly web interface for convenience. We expect that BaSDAS will be a useful tool for the analysis of genome-wide screening data and will support the development of novel drugs based on functional genomics information.

16.
ACS Sens ; 4(12): 3248-3256, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31680513

RESUMEN

The quantitative analysis of human platelets is important for the diagnosis of various hematologic and cardiovascular diseases. In this article, we present a stochastic particle impact electrochemical (SPIE) approach for human platelets with fixation (F-HPs). Carboxylate-functionalized polystyrene particles (PSPs) are studied as well as a standard platform of SPIE-F-HPs. For SPIE-PSPs (or F-HPs), [Fe(CN)6]4- was used as the redox mediator, and electro-oxidation of [Fe(CN)6]4- to [Fe(CN)6]3- was conducted on a Pt ultramicroelectrode (UME) by applying a constant potential, where the corresponding oxidation current is mass-transfer-controlled. When PSPs (or F-HPs) are introduced into aqueous solution with [Fe(CN)6]4-, sudden current drops (SCDs) were observed, which resulted from the partial blockage of a Pt UME by collision of an individual PSP (or F-HP). For SPIE-PSPs (or F-HPs), we found that it is essential to enhance the migration of PSPs (F-HPs) toward a Pt UME by maximizing the steady state current associated with electro-oxidation of [Fe(CN)6]4-. This was accomplished by increasing its concentration to the solubility limit. We successfully measured the concentration of F-HPs dispersed in aqueous solution containing [Fe(CN)6]4- with a minimum detectable concentration of 0.1 fM, and the size distribution of F-HPs was also estimated from the obtained idrop distribution based on the SPIE analysis, where idrop stands for the magnitude of the current drop of each SCD. Lastly, we revealed that HPs without the fixation process (WF-HPs) are difficult to quantitatively analyze by SPIE because of their transient activation process, which results in changes from their spherical shape. The observed difficulty was also confirmed by finite element analysis, which shows that idrop can be significantly increased, as an elongated WF-HP is adsorbed on the edge of an UME.


Asunto(s)
Plaquetas/química , Separación Celular/métodos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Ferrocianuros/química , Humanos , Microelectrodos , Oxidación-Reducción , Platino (Metal)/química , Poliestirenos/química , Procesos Estocásticos
17.
RSC Adv ; 9(16): 9049-9052, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35517656

RESUMEN

Solvent-, acidity-, and redox-responsive thione(thiol)-disulfide interconversion were achieved by a dinuclear copper(ii) complex bearing a bis(thiosemicarbazone) (bTSC) ligand. The role of copper(ii) ion coordination was rationalized by parallel comparison with a bare bTSC ligand and zinc(ii) bTSC complexes under identical reaction conditions.

18.
Sci Rep ; 8(1): 12348, 2018 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-30120377

RESUMEN

Transition metal-doped SnO2 nanoparticles (TM-SnO2) were synthesized by applying a thermos-synthesis method, which first involved doping SnO2 with Sb and then with transition metals (TM = Cr, Mn, Fe, or Co) of various concentrations to enhance a catalytic effect of SnO2. The doped particles were then analyzed by using various surface analysis techniques such as transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning transmission X-ray microscopy (STXM), and high-resolution photoemission spectroscopy (HRPES). We evaluated the catalytic effects of these doped particles on the oxidation of L-cysteine (Cys) in aqueous solution by taking electrochemical measurements and on the photocatalytic oxidation of Cys by using HRPES under UV illumination. Through the spectral analysis, we found that the Cr- and Mn-doped SnO2 nanoparticles exhibit enhanced catalytic activities, which according to the various surface analyses were due to the effects of the sizes of the particles and electronegativity differences between the dopant metal and SnO2.


Asunto(s)
Cisteína/metabolismo , Electroquímica , Nanopartículas del Metal/química , Oxidación-Reducción , Procesos Fotoquímicos , Compuestos de Estaño/química , Electroquímica/métodos , Nanopartículas del Metal/ultraestructura , Elementos de Transición
19.
Anal Chem ; 90(12): 7261-7266, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29847933

RESUMEN

Herein, a study on a new lower critical solution temperature (LCST) polymer in an organic solvent by an electrochemical technique has been reported. The phase-transition behavior of poly(arylene ether sulfone) (PAES) was examined on 1,2-dimethoxyethane (DME). At a temperature above the LCST point, polymer molecules aggregated to create polymer droplets. These droplets subsequently collided with an ultramicroelectrode (UME), resulting in a new form of staircase current decrease. The experimental collision frequency and collision signal were analyzed in relation to the concentration of the polymer. In addition, the degree of polymer aggregation associated with temperature change was also observed.

20.
Biosens Bioelectron ; 110: 155-159, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29609162

RESUMEN

Blood tests (e.g., red blood cell (RBC) count) are crucial for detecting, diagnosing, and monitoring the progression of blood disorders. Here, we report the development of a new and rapid method for electrochemically detecting RBCs using single-particle collision events. The principle of this method relies on the electrochemical oxidation of an electroactive redox species (potassium ferrocyanide) hindered by an RBC attached to an electrode surface. A decrease in staircase current, caused by the collision of RBCs on the electrode, was observed. The magnitude of this current decrease could provide quantitative information on the size and concentration of RBCs, which could be converted into the mean corpuscular volume (MCV) and used for diagnosis. Anemia-related diseases caused by abnormal count of RBCs (e.g., erythrocytosis, pernicious anemia) or abnormal RBC size (e.g. megaloblastic anemia, microcytic anemia) could be detected easily and quickly using this electrochemical collision method, potentially leading to extensive applications in hematology and point-of-care blood testing devices.


Asunto(s)
Técnicas Electroquímicas/instrumentación , Recuento de Eritrocitos/instrumentación , Índices de Eritrocitos , Eritrocitos/citología , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Diseño de Equipo , Recuento de Eritrocitos/métodos , Humanos , Microelectrodos , Oxidación-Reducción
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