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BACKGROUND: Humans' nervous system has a limited ability to repair nerve cells, which poses substantial challenges in treating injuries and diseases. Stem cells are identified by the potential to renew their selves and develop into several cell types, making them ideal candidates for cell replacement in injured neurons. Neuronal differentiation of embryonic stem cells in modern medicine is significant. Nanomaterials have distinct advantages in directing stem cell function and tissue regeneration in this field. We attempted in this systematic review to collect data, analyze them, and report results on the effect of nanomaterials on neuronal differentiation of embryonic stem cells. METHODS: International databases such as PubMed, Scopus, ISI Web of Science, and EMBASE were searched for available articles on the effect of nanomaterials on neuronal differentiation of embryonic stem cells (up to OCTOBER 2023). After that, screening (by title, abstract, and full text), selection, and data extraction were performed. Also, quality assessment was conducted based on the STROBE checklist. RESULTS: In total, 1507 articles were identified and assessed, and then only 29 articles were found eligible to be included. Nine studies used 0D nanomaterials, ten used 1D nanomaterials, two reported 2D nanomaterials, and eight demonstrated the application of 3D nanomaterials. The main biomaterial in studies was polymer-based composites. Three studies reported the negative effect of nanomaterials on neural differentiation. CONCLUSION: Neural differentiation is crucial in neurological regenerative medicine. Nanomaterials with different characteristics, particularly those cellular regulating activities and stem cell fate, have much potential in neural tissue engineering. These findings indicate a new understanding of potential applications of physicochemical cues in nerve tissue engineering.
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Células Madre Embrionarias , Nanoestructuras , Humanos , Neuronas/metabolismo , Ingeniería de Tejidos/métodos , Diferenciación CelularRESUMEN
This study investigated the efficiency of hydrochar derived from hydrothermal fulvification of wheat straw in adsorbing malachite green (MG) dye. The characterizations of the hydrochar samples were determined using various analytical techniques like SEM, EDX, FTIR, X-ray spectroscopy, BET surface area analysis, ICP-OES for the determination of inorganic elements, elemental analysis through ultimate analysis, and HPLC for the content of sugars, organic acids, and aromatics. Adsorption experiments demonstrated that hydrochar exhibited superior removal efficiency compared to feedstock. The removal efficiency of 91 % was obtained when a hydrochar dosage of 2 g L-1 was used for 20 mg L-1 of dye concentration in a period of 90 min. The results showed that the study data followed the Freundlich isotherms as well as the pseudo-second order kinetic model. Moreover, the determined activation energy of 7.9 kJ mol-1 indicated that the MG adsorption was a physical and endothermic process that increased at elevated temperatures. The study also employed an artificial neural network (ANN), a machine learning approach that achieved remarkable R2 (0.98 and 0.99) for training and validation dataset, indicating high accuracy in simulating MG adsorption by hydrochar. The model's sensitivity analysis demonstrated that the adsorbent dosage exerted the most substantial influence on the adsorption process, with MG concentration, pH, and time following in decreasing order of impact.
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In this study, copper oxide nanoparticles (CuONPs) were prepared by a simple chemical method and then characterized by scanning electron microscope (SEM). A novel electrochemical sensor for hydrogen peroxide (H2O2) analysis was prepared by immobilizing copper oxide nanoparticles and polyalizarin yellow R (PYAR) on bare glassy carbon electrode (PAYR/CuONPs/GCE). The electrocatalytical behavior of the proposed electrochemical sensor was also studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). Based on the results, the PAYR/CuONP nanocomposite had significant electrocatalytic oxidation and reduction properties for the detection and determination of H2O2. Some parameters such as linear range, sensitivity, and detection limit for reduction peak were obtained as 0.1-140 µM, 1.4154 µA cm-2 µM-1, and 0.03 µM, respectively, by the DPV technique. Some advantages of this electrode were having widespread linear range, low detection limit, and, most importantly, ability in simultaneous oxidation and reduction of H2O2 at two applied potentials.
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Grafito , Nanocompuestos , Nanopartículas , Cobre , Técnicas Electroquímicas , Electrodos , Peróxido de Hidrógeno , Límite de DetecciónRESUMEN
Because ADAM17 promotes colonic tumorigenesis, we investigated potential miRNAs regulating ADAM17; and examined effects of diet and tumorigenesis on these miRNAs. We also examined pre-miRNA processing and tumour suppressor roles of several of these miRNAs in experimental colon cancer. Using TargetScan, miR-145, miR-148a, and miR-152 were predicted to regulate ADAM17. miR-143 was also investigated as miR-143 and miR-145 are co-transcribed and associated with decreased tumour growth. HCT116 colon cancer cells (CCC) were co-transfected with predicted ADAM17-regulating miRNAs and luciferase reporters controlled by ADAM17-3'UTR. Separately, pre-miR-143 processing by colonic cells was measured. miRNAs were quantified by RT-PCR. Tumours were induced with AOM/DSS in WT and transgenic mice (Tg) expressing pre-miR-143/miR-145 under villin promoter. HCT116 transfection with miR-145, -148a or -152, but not scrambled miRNA inhibited ADAM17 expression and luciferase activity. The latter was suppressed by mutations in ADAM17-3'UTR. Lysates from colonocytes, but not CCC, processed pre-miR-143 and mixing experiments suggested CCC lacked a competency factor. Colonic miR-143, miR-145, miR-148a, and miR-152 were downregulated in tumours and more moderately by feeding mice a Western diet. Tg mice were resistant to DSS colitis and had significantly lower cancer incidence and tumour multiplicity. Tg expression blocked up-regulation of putative targets of miR-143 and miR-145, including ADAM17, K-Ras, XPO5, and SET. miR-145, miR-148a, and miR-152 directly suppress colonocyte ADAM17 and are down-regulated in colon cancer. This is the first direct demonstration of tumour suppressor roles for miR-143 and miR-145 in an in vivo model of colonic tumorigenesis.
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Colitis , Neoplasias del Colon , MicroARNs , Animales , Neoplasias del Colon/genética , Metilación de ADN , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Inflamación , Carioferinas , Ratones , MicroARNs/metabolismo , Regulación hacia ArribaRESUMEN
Improved electron transfer properties and catalytic activity of manganese oxide (MnOx) was demonstrated following its electrochemical deposition on a deoxyribonucleic acid (DNA) modified glassy carbon electrode. The MnOx showed different morphologies, electrocatalytic properties and electrochemical kinetics. Scanning electron microscopy showed that electrodeposition of MnOx on a bare glassy carbon electrode led to the formation of irregular-shapes while a nanowire cluster (NWC) was formed on a GCE/DNA due to the DNA serving as a template. Electrochemical impedance spectroscopy (EIS) revealed lower charge transfer resistance of the MnOxNWC compared with MnOx. A new mechanism is presented for the electrodeposition of MnOx on the surface of a GC/DNA electrode. An electrochemical biosensor was fabricated based on depositing MnOx onto a glassy carbon /DNA electrode (GCE/DNA/MnOxNWC) and was used to detect hydrogen peroxide (H2O2). The MnOx nanowire cluster and DNA exhibited significant electrocatalytic activity for simultaneous electrocatalytic oxidation at two oxidation potentials (0.6 V and 0.98 V vs Ag/AgCl) and one reduction potential (-0.5 V vs Ag/AgCl) for H2O2 at pH 6.0. A new mechanism for the detection of H2O2 is presented. Excellent electrocatalytic activity, stability and facility for simultaneous detection of H2O2 at different of applied potentials are proposed advantages of the proposed electrochemical biosensor.
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ADN/química , Peróxido de Hidrógeno/análisis , Compuestos de Manganeso/química , Nanocables/química , Óxidos/química , Moldes Genéticos , Reproducibilidad de los ResultadosRESUMEN
A novel electrochemical modified electrode for the impedimetric mechanism study of horseradish peroxidase and hydrogen peroxide was proposed based on immobilizing horseradish peroxidase/3(trimethoxysilyl) propylamine/graphene on glassy carbon electrode (HRP/TMSPA/Gr/GCE). Cyclic voltammetry and SEM were utilized to corroborate the successful stepwise assemblage procedure of the electrode. The electrochemical impedance spectroscopy measurements revealed that the charge transfer resistance increases at low concentrations and significantly decreases at high concentrations after enzymatic reaction with hydrogen peroxide. The mechanism study of the horseradish peroxidase and hydrogen peroxide were also investigated by electrochemical impedance spectroscopy.
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Electroquímica , Enzimas Inmovilizadas/química , Peroxidasa de Rábano Silvestre/química , Peróxido de Hidrógeno/química , Espectroscopía Dieléctrica , Electrodos , Grafito/química , Nanotubos de Carbono/química , Transición de FaseRESUMEN
Amyloid fibrils were produced in a solution of bovine serum albumin (BSA) in buffer solution in the presence of fructose. The solution was incubated for 20â¯weeks in the dark. We used glycation induced bovine serum albumin in which fibrilogenesis (nano fibrils) followed by using fluorescence (Thioflavin T), Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) to achieve the size and morphology of fibrils. A novel electrochemical biosensor for the detection of hydrogen peroxide was developed based on immobilizing poly (alizarin yellow R) and amyloid nano-fibrils on glassy carbon electrode (PAYR/AMLNFibs/GCE). The electrocatalytic response of the biosensor was proportional to the hydrogen peroxide concentration in the range of 1⯵M to 2.2â¯mM with a limit of detection and sensitivity of 290â¯nM and 0.024⯵A/µM, respectively. The modified electrode demonstrated many advantages such as high sensitivity, low detection of limit and excellent catalytic activity.
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Amiloide/química , Compuestos Azo/química , Electroquímica/métodos , Peróxido de Hidrógeno/análisis , Nanocompuestos/química , Nanofibras/química , Animales , Técnicas Biosensibles , Catálisis , Bovinos , Espectroscopía Dieléctrica , Dispersión Dinámica de Luz , Electrodos , Fluorescencia , Glicosilación , Leche/química , Nanofibras/ultraestructura , Oxidación-Reducción , Reproducibilidad de los Resultados , Albúmina Sérica Bovina/química , Espectrometría de FluorescenciaRESUMEN
Based on immobilizing manganese oxide nanospheres (MnOxNsph)/deoxyribonucleic (DNA) on glassy carbon electrode (MnOxNsph/DNA/GCE), a new electrochemical biosensor for the detection of thiourea (TU) was fabricated. In order to prepare DNA template, cyclic voltammetry (CV) method was used. Scanning electron microscopy (SEM) was used for characterization of MnOx/DNA. Electrochemical impedance spectroscopy was utilized to confirm the successful stepwise assembly procedure of the biosensor. The electrocatalytical behaviors of the biosensor were also investigated by cyclic voltammetry and differential pulse voltammetry (DPV). The results showed that MnOxNsph/DNA exhibited a remarkable electrocatalytic activity for the oxidation of TU under optimal conditions. The linear range, detection of limit and sensitivity were calculated for oxidation peaks (OX1 and OX2). This electrode demonstrated many advantages such as high sensitivity, low detection of limit, excellent catalytic activity at natural pH values, remarkable antifouling property toward TU and its oxidation product for the two oxidation peaks.