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In this study, a thin poly (methyl methacrylate) coating was formed on a self-assembled monolayer formed on a gold plate after chemically binding estrone. Subsequently, the estrone molecules were hydrolyzed and extracted using a solvent to form a molecular-imprinted system. The estrone-imprinted gold plate was then used as a working electrode to measure the estrone recognition ability through electrochemical methods. The recognition ability of this working electrode was evaluated for similar compounds. The selectivity factors for the seven estrone analogs were measured, and these values ranged from 0.19 to 0.67. According to the experimental results, the estrone-imprinted system showed good differentiation of estrone from other estrone analogs. Comparing these selectivity factors with those of a previous study on a cholesterol-imprinted system, the relative molecular size difference between the target molecule and similar molecules had a significant impact on the selectivity factor.
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To tackle the challenge of ground-level ozone pollution, this study proposed a potential catalytic design approach for ozone decomposition using Cu-Mn bimetallic oxide. This approach is grounded in an understanding of the intrinsic reactivity for catalyst and incorporates a novel potassium-driven low-temperature oxidation process for catalyst synthesis. The research highlights the creation of a highly reactive Cu-Mn oxide phase with extensive defect coverage, leading to significantly increased reaction rates. It also identifies the MnO2(100) facet as a crucial active phase, where oxygen vacancies simultaneously enhance O3 adsorption and decomposition, albeit with a concurrent risk of O2 poisoning due to the stabilization of adsorbed O2. Crucially, the incorporation of Cu offsets the effects of oxygen vacancies, influencing conversion rates and lessening O2 poisoning. The synergistic interplay between Cu and oxygen vacancies elevates the performance of the defect-rich Cu-Mn oxide catalyst. By combining computational and experimental methods, this study not only advances the understanding of the Cu-Mn oxide system for ozone decomposition but also contributes valuable insights into developing more efficient catalysts to mitigate ozone pollution.
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This study develops a vitamin C controlled-release system, trackable via color changes as a function of vitamin C release. The system is composed of coaxial microfibers prepared via coaxial electrospinning, with a core of poly(ethylene oxide) (PEO) incorporating vitamin C, and a shell composed of polycaprolactone (PCL) containing polydiacetylene (PDA) as the color-changing material. The shell thickness is controlled by adjusting the amount of PCL ejected during electrospinning, allowing regulation of the release rate of vitamin C. When vitamin C added to PEO penetrates the PCL layer, the color of PDA changes from blue to red, indicating a color change. The results of this study can be applied to devices that require immediate detection of vitamin C release levels.
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Compared to infant formula, breast milk is the best source of nutrition for infants; it not only improves the neonatal intestinal function, but also regulates the immune system and gut microbiota composition. However, probiotic-fortified infant formula may further enhance the infant gut environment by overcoming the limitations of traditional infant formula. We investigated the probiotic formula administration for one month by comparing 118 Korean infants into the following three groups: infants in each group fed with breast milk (50), probiotic formula (35), or placebo formula-fed group (33). Probiotic formula improved stool consistency and defecation frequency compared to placebo formula-fed group. The probiotic formula helped maintaining the level of secretory immunoglobulin A (sIgA), which had remarkably decreased over time in placebo formula-fed infants (compared to weeks 0 and 4). Moreover, probiotic formula decreased the acidity of stool and considerably increased the butyrate concentration. Furthermore, the fecal microbiota of each group was evaluated at weeks 0 and 4. The microbial composition was distinct between each groups, and the abundance of health-promoting bacteria increased in the probiotic formula compared to the placebo formula-fed group. In summary, supplementation of probiotic infant formula can help optimize the infant gut environment, microbial composition, and metabolic activity of the microbiota, mimicking those of breast milk.
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In this study, the basic probiotic characteristics and functional properties of lactic acid bacteria (LAB) were investigated using two in vitro models of inflammation induced by lipopolysaccharide (LPS) and H2O2. Fifteen strains were prescreened out of 60 LAB candidates based on their radical scavenging activity to determine the antioxidant capacity of the strains. The top 15 candidates were further investigated to evaluate their survival rate under low pH and bile salt conditions that mimic the intestinal environment. Three strains, Levilactobacillus brevis D70 (Levilact), Lactiplantibacillus pentosus S16 (Lactipla), and Limosilactobacillus fermentum MF10 (Limosilact), were capable of scavenging free radicals and survived under artificial intestinal conditions. Therefore, Levilact. brevis D70, Lactipla. pentosus S16, and Limosilact. fermentum MF10 were selected for further antioxidant, anti-inflammation, and mitochondrial activity examinations via cell models of inflammation and oxidative stress. Among the three strains, Limosilact. fermentum MF10 showed the highest anti-inflammatory activities by significantly downregulating the relative mRNA expression levels of inflammatory biomarkers such as interleukin 8 (IL-8) and interferon-gamma (IFN-γ) induced by LPS (P < 0.05). Moreover, Limosilact. fermentum MF10 was also capable of upregulating the gene expression levels of antioxidative mediator glutathione peroxidase 4 (GPX4) induced by reactive oxygen species (ROS) in both human HT-29 epithelial cells and human HaCaT keratinocytes. Limosilact. fermentum MF10 was also capable of regulating mitochondrial membrane potential (MMP), which plays a key role in the mitochondrial activity of HaCaT cells. As a result, Limosilact. fermentum MF10 showed the highest potential for probiotic properties and impacts the immune-related gut-skin axis by altering proinflammatory cytokines, antioxidative biomarkers, and MMP.
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Lactobacillales , Probióticos , Humanos , Antioxidantes/farmacologia , Lactobacillales/genética , Células HaCaT , Peróxido de Hidrogênio , Lipopolissacarídeos , Probióticos/farmacologia , Inflamação , Anti-Inflamatórios/farmacologia , Ácido Láctico , BiomarcadoresRESUMO
A molecularly imprinted system is introduced here whose color gradually changes as the analyte becomes rebound. The MIP was prepared from an acryloyl-modified ß-cyclodextrin (ß-CD), acrylamide (AAm), and N,N'-methylenebisacrylamide (MBAA), and imprinted with bisphenol A (BPA). The sensing capability of the MIP was first tested by potentiometry. A spin-coated gold plate coated with the MIP was used as a working electrode; the electrode can differentiate BPA from phenol or p-cresol, which were used as analogs of BPA. Next, a color-responsive system was fabricated by forming a hydrogel membrane containing the modified ß-CD, AAm, and MBAA. A vesicle solution was prepared from N-(2-aminoethyl)pentacosa-10,12-diynamide by sonication and incorporated into the hydrogel. The blue polydiacetylene was formed by UV photopolymerization. In the presence of BPA, this system undergoes a color change from blue to red that is proportional to the degree of BPA rebinding. The color change is due to the contraction of the gel membrane that rebinding causes. The method works to 0.5 mM BPA concentration range. The detection limits for BPA are 0.1 mM on visual assessment and 50 µM on spectrophotometric readout. Graphical AbstractA molecular imprinting system is described whose color changes from blue to red as it binds bisphenol A. The degree of rebinding can be measured by detecting the color change of polydiacetylene vesicle. CD: cyclodextrin, BPA: bisphenol A.
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Highly active catalyst systems for polymerizing 2,6-dimethylphenol were studied by using aromatic amine ligands and copper(I) chloride. The aromatic amine ligands employed were pyridine, 1-methylimidazole, 2-aminopyridine, 3-aminopyridine, and 4-aminopyridine. A mixture of chloroform and methanol (9:1, v/v) was used as a polymerization solvent. All experiments were performed with oxygen uptake measurement apparatus, while the reaction rate for each aromatic amine ligand-Cu catalyst system and the amount of by-product, 3,3',5,5'-Tetramethyl-4,4'diphenoquinone (DPQ), were measured to determine the efficiency of the catalyst systems. The 4-aminopyridine/Cu (I) catalyst system was found to be extremely efficient in poly(2,6-dimethyl-1,4-phenylene ether) (PPE) synthesis; it had the fastest reaction rate of 6.98 × 10-4 mol/L·s and the lowest DPQ production. The relatively high basicity of 4-aminopyridne and the less steric hindrance arising from a coordination of Cu and 4-aminopyridine in this catalyst are responsible for the fast polymerization rate. When 2-aminoprydine (an isomer of 4-aminopyridine) was used as a ligand, however, no polymerization occurred probably due to steric hindrance.
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The thermal chromatic sensitivity of polydiacetylenes (PDAs) with 10,12-pentacosadiynoic acid (PCDA) derivatives, which have a hydroxyl group (HEEPCDA) and an amine group (APPCDA), were investigated using D2O and H2O as solvents. The vesicle solution with polymerized HEEPCDA exhibited a reversible chromatic response during the heating and cooling cycle in D2O, but not in H2O. On the other hand, the vesicle solution with the polymerized APPCDA exhibited a reversible chromatic response in H2O during the heating and cooling cycle, but the color of the solution did not change much in D2O. The critical vesicle concentration of HEEPCDA was lower in D2O than in H2O, and the chromatic sensitivity of the polymerized vesicles to temperature was slower in D2O than in H2O. We think that it is due to D2O being a more highly structured solvent than H2O with the hydrogen bonding in D2O stronger than that in H2O.
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It has previously been suggested that reactive oxygen species (ROS) are involved in the pathogenesis of chronic inflammatory diseases, which entails the initial activation of pro-inflammatory cytokines to facilitate leukocyte transmigration. The present study investigated whether intracellular superoxide dismutase (SOD) suppressed monocyte endothelial trafficking and transmigration. Human umbilical vein endothelial cells (HUVECs) and THP-1 monocytes were activated by the cytokine tumor necrosis factor-α (TNF-α) in the absence and presence of cell-permeable transactivator of transcription (Tat)-SOD protein. External stimulation with SOD was conducted using endothelial cells and monocytes. Purified cell-permeable Tat-SOD, but not non-targeted SOD, at 1-3 µM was transduced into endothelial cells in a time and dose-dependent manner. Non-toxic Tat-SOD at ≤0.5 µM, but not 1 µM SOD, blocked the monocyte-endothelium interactions by inhibiting the TNF-α-induced stimulation of vascular cell adhesion molecule-1 (VCAM-1) in HUVECs and integrin ß1 in THP-1 cells. Endothelial VCAM-1 induction by TNF-α was responsible for superoxide anion production being quenched by N-acetyl-cysteine and Tat-SOD. SOD treatment markedly inhibited superoxide anion production induced by TNF-α, but no inhibition of endothelial transmigration was noted. Tat-SOD prevented transendothelial monocyte migration by firmly localizing occludin-1, platelet/endothelial cell adhesion molecule1 (PECAM-1) and vascular endothelialcadherin present in paracellular junctions and inhibiting endothelial induction and activation of matrix-degrading membrane type-1 (MT-1) matrix metalloproteinase (MMP), MMP-2 and MMP-9. By contrast, treatment with 1 µM SOD did not have such effects. Furthermore, transduced Tat-SOD hindered nuclear transactivation of nuclear factor-κB (NF-κB), modulating the induction of paracellular junction proteins and matrixdegrading MMP in TNF-αstimulated HUVECs. Transduced Tat-SOD, but not external SOD, impeded cytokine-induced endothelial adhesion and the transmigration of monocytes. Thus, we suggest that transduced Tat-SOD qualifies as an atheroprotective agent against oxidation-driven and inflammation-associated atherosclerosis.
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Aterosclerose/genética , Inflamação/genética , Superóxido Dismutase/genética , Aterosclerose/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/patologia , Monócitos/metabolismo , Monócitos/patologia , NF-kappa B/biossíntese , Oxirredução/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Transporte Proteico/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/biossíntese , Superóxido Dismutase-1 , Ativação Transcricional , Transdução Genética , Fator de Necrose Tumoral alfa/biossíntese , Molécula 1 de Adesão de Célula Vascular/biossínteseRESUMO
The noble vesicular system of polydiacetylene showed a red shift using two types of detecting systems. One of the systems involves the absorption of target materials from the outer side of the vesicle, and the other system involves the permeation through the vesicular layers from within the vesicle. The chromatic mixed vesicles of N-(2-aminoethyl)pentacosa-10,12-diynamide (AEPCDA) and dimethyldioctadecylammonium chloride (DODAC) were fabricated by sonication, followed by polymerization by UV irradiation. The stability of monomeric vesicles was observed to increase with the polymerization of the vesicles. Methotrexate was used as a target material. The polymerized mixed vesicles having a blue color were exposed to a concentration gradient of methotrexate, and a red shift was observed indicating the adsorption of methotrexate on the polydiacetylene bilayer. In order to check the chromatic change by the permeation of methotrexate, we separated the vesicle portion, which contained methotrexate inside the vesicle, and checked chromatic change during the permeation of methotrexate through the vesicle. The red shift apparently indicates the disturbance in the bilayer induced by the permeation of methotrexate. The maximum contrast of color appeared at the equal molar ratio of AEPCDA and DODAC, indicating that the formation of flexible and deformable vesicular layers is important for red shift. Therefore, it is hypothesized that the system can be applicable for the chromatic detection of the permeation of methotrexate through the polydiacetylene layer.
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Immobilized metal affinity monolith column as a new class of chromatographic support is shown to be superior to conventional particle-based column as plasmid DNA (pDNA) purification platform. By harnessing the affinity of endotoxin to copper ions in the solution, a majority of endotoxin (90%) was removed from the alkaline cell lysate using CuCl(2)-induced precipitation. RNA and remaining endotoxin were subsequently removed to below detection limit with minimal loss of pDNA using either monolith or particle-based column. Monolith column has the additional advantage of feed concentration and flowrate-independent dynamic binding capacity for RNA molecules, enabling purification process to be conducted at high feed RNA concentration and flowrate. The use of monolith column gives three fold increased productivity of pDNA as compared to particle-based column, providing a more rapid and economical platform for pDNA purification.
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Cromatografia de Afinidade/métodos , DNA/isolamento & purificação , Plasmídeos/isolamento & purificação , Resinas Sintéticas/química , Adsorção , Cromatografia de Afinidade/instrumentação , DNA/química , Metais/química , Plasmídeos/químicaRESUMO
This study investigated the preventive effect of ribosomal protein S3 (rpS3) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice. A cell permeable expression vector PEP-1-rpS3 was constructed. Topical application of the vector markedly inhibited TPA-induced expression levels of cyclooxygenase-2 (COX-2) and pro-inflammatory cytokines. Application of PEP-1-rpS3 also resulted in a significant reduction in the activation of nuclear factor-kappa B (NF-kB) and mitogen-activated protein kinase (MAPK) in TPA-treated ears. These results indicate that PEP-1-rpS3 inhibits inflammatory response cytokines and enzymes by blocking NF-kB and MAPK, prompting the suggestion that PEP-1-rpS3 can be used as a therapeutic agent against skin inflammation.
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Dermatite/prevenção & controle , Mediadores da Inflamação/fisiologia , Peptídeo Hidrolases/genética , Proteínas de Plantas/genética , Proteínas Ribossômicas/genética , Acetato de Tetradecanoilforbol/toxicidade , Animais , Dermatite/genética , Dermatite/patologia , Edema/genética , Edema/patologia , Edema/prevenção & controle , Vetores Genéticos/uso terapêutico , Humanos , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Peptídeo Hidrolases/uso terapêutico , Proteínas de Plantas/uso terapêutico , Proteínas Ribossômicas/uso terapêutico , Acetato de Tetradecanoilforbol/antagonistas & inibidores , Transdução Genética/métodosRESUMO
Arginine deiminase (ADI), an arginine-degrading enzyme, has anti-proliferative and anti-tumor activities and is capable of inhibiting the production of nitric oxide (NO). Modulation of nitric oxide (NO) production is considered a promising approach for the treatment of various diseases including cancer, inflammation and neuronal disorders. In this study, an ADI gene was fused with an HIV-1 Tat peptide in a bacterial expression vector to produce an genetic in-frame Tat-ADI fusion protein. When added exogenously to the culture media, the expressed and purified Tat-ADI fusion proteins were efficiently transduced into macrophage Raw 264.7 cells in a time- and dose-dependent manner. Furthermore, transduced Tat-ADI fusion proteins markedly increased cell viability in cells treated with lipopolysaccharide (LPS). This increase in viability was mediated by an inhibition of NO production. These results suggest that this Tat-ADI fusion protein can be used in protein therapies of NO-related disorders such as cancer, inflammation and neuronal diseases.
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Produtos do Gene tat , Hidrolases , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/biossíntese , Proteínas Recombinantes de Fusão , Animais , Linhagem Celular , Sobrevivência Celular , Produtos do Gene tat/genética , Produtos do Gene tat/metabolismo , HIV-1/metabolismo , Humanos , Hidrolases/genética , Hidrolases/metabolismo , Macrófagos/citologia , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismoRESUMO
Familial Amyotrophic lateral sclerosis (FALS) is a progressive neurodegenetative disorder induced by mutations of the SOD1 gene. Heat shock protein 27 (HSP27) is well-defined as a stress-inducible protein, however the its role in ALS protection has not yet been established. To investigate the role HSP27 may have in SOD1 mutant-mediated apoptosis, human SOD1 or HSP27 genes were fused with a PEP-1 peptide in a bacterial expression vector to produce a genetic in-frame fusion protein, which was then transduced into cells. We found the purified PEP-1-HSP27 fusion proteins can be transduced efficiently into neuronal cells and protect against cell death by enhancing mutant SOD1 activity. Moreover, transduced PEP-1-HSP27 efficiently prevents protein aggregation produced by oxidative stress. These results suggest that transduced HSP27 fusion protein may be explored as a potential therapeutic agent for FALS patients.
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Esclerose Lateral Amiotrófica/enzimologia , Citoproteção , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas Mutantes/metabolismo , Neurônios/citologia , Superóxido Dismutase/metabolismo , Transdução Genética , Astrócitos/citologia , Astrócitos/metabolismo , Morte Celular , Sobrevivência Celular , Cisteamina/análogos & derivados , Cisteamina/metabolismo , Proteínas de Choque Térmico , Humanos , Chaperonas Moleculares , Neurônios/metabolismo , Estresse Oxidativo , Peptídeos/metabolismo , Estrutura Quaternária de Proteína , Proteínas Recombinantes de Fusão/isolamento & purificação , Superóxido Dismutase/química , Superóxido Dismutase-1RESUMO
Tumor necrosis factor (TNF)-related, apoptosis-inducing ligand (Apo2L/TRAIL) has a unique homotrimeric structure, and its conformational stability is essential for its apoptotic activity. The conformational stability of a modified version of TRAIL(114-281) with two additional domains of histidine tag and isoleucine zipper [His-ILZ-TRAIL(114-281)] was evaluated in various pH environments according to three different biological or physicochemical considerations: cytotoxicity, antibody-binding affinity, and tertiary structure. The biological properties of His-ILZ-TRAIL(114-281) were the most stably maintained at pH 6.0. The physicochemical analyses (circular dichroism and fluorescence spectroscopy) demonstrate that its bioactivity loss by pH challenge was originated from its structural collapse as a homotrimer.
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Ligante Indutor de Apoptose Relacionado a TNF/química , Afinidade de Anticorpos/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Meia-Vida , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Cinética , Conformação Proteica/efeitos dos fármacos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Termodinâmica , Fatores de TempoRESUMO
The laser generation method of focused-Lamb wave is expected to have high defect-detection ability with advantages of non-contact testing. In this method, the laser beam is illuminated on the surface of the object through an arrayed-arc slit, and then the energy of the generated Lamb wave is concentrated on the focus point of arc. This focusing effect enables the concentration of higher wave intensity on the focus with better S/N ratio of signal, and has better spatial resolution compared to the conventional line arrayed method. This paper describes a 2-D imaging system using this laser generated, focused-Lamb wave combined with its detection by the air-coupled transducer. This technique is fully non-contact so it can be easily applied for the automatic inspection. The effectiveness of the proposed method was verified by experiments on a 1-mm thick aluminum plate with artificial drill-hole defect with diameters of 1mm. The 2-D image of was constructed by scanning and the result showed that the location and size of defects were clearly detected.