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1.
Chemistry ; 29(27): e202300250, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-36958938

RESUMEN

In this study, a highly air stable and eco-friendly methyl ammonium bismuth iodide (MA3 Bi2 I9 ) perovskite-like material has been prepared. After physiochemical characterizations, the synthesized MA3 Bi2 I9 was utilized as photo-catalyst towards hydrogen production. It is important to design and synthesize lead (Pb)-free perovskite-like material (MA3 Bi2 I9 ) for photo-catalytic hydrogen-production applications. The synthesized MA3 Bi2 I9 exhibits excellent photo-catalytic hydrogen generation with a production rate of 11.43 µmolg-1 h-1 . In the presence of a platinum co-catalyst, the hydrogen production rate further increases to 172.44 µmolg-1 h-1 . The MA3 Bi2 I9 photo-catalyst also demonstrates excellent cyclic stability.

2.
Chemistry ; 29(35): e202300513, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37029556

RESUMEN

In the past few years, there has been a significant increase in the development and production of perovskite or perovskite-like materials that do not contain lead (Pb) for the purpose of constructing solar cells. The development and testing of lead-free perovskite-like structures for solar cells is crucial. In this study, we used the solar cell capacitance software (SCAPS) to simulate perovskite solar cells based on methyl ammonium bismuth iodide (MA3 Bi2 I9 ). The electron-transport layer, hole-transport layer, and absorber layer thickness were optimized using SCAPS. The simulated perovskite solar cells (FTO/TiO2 /MA3 Bi2 I9 /spiro-OMeTAD/Au) performed well with a power conversion efficiency of 14.07 % and a reasonable open circuit voltage of 1.34 V, using the optimized conditions determined by SCAPS. Additionally, we conducted experiments to fabricate perovskite solar cells under controlled humidity, which showed a power conversion efficiency of 1.31 %.


Asunto(s)
Programas Informáticos , Simulación por Computador
3.
Environ Res ; 231(Pt 3): 116288, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37263474

RESUMEN

The removal of dyes from wastewater by photocatalytic technologies has received substantial attention in recent years. In the present study, novel Z-scheme V2O5/g-C3N4 photocatalytic composites were organized via simple hydrothermal processes and a sequence of several characterization aspects. The degradation results showed that the optimum Z-scheme GVO2 heterostructure composite photocatalysts (PCs) had a better efficiency (90.1%) and an apparent rate (0.0136 min-1) for the methylene blue (MB) aqueous organic dye degradation, which was about 6.18-fold higher than that of pristine GCN catalyst. Meanwhile, the GVO2 heterostructured PCs showed better recycling stability after five consecutive tests. Moreover, the free radical trapping tests established that •O2- and h+ species were the prime reactive species in the photocatalytic MB degradation process in the heterostructured PCs. The photocatalytic enhanced activity was primarily recognized as the synergistic interfacial construction of the Z-scheme heterojunctions among V2O5 and GCN, which improved the separation/transfer, lower recombination rate, extended visible-light utilization ability, and enhanced reaction rate. Therefore, the existing study affords a simple tactic for the development of a direct Z-scheme for photocatalytic heterojunction nanomaterials for potential environmental remediation applications.


Asunto(s)
Contaminantes Ambientales , Restauración y Remediación Ambiental , Colorantes , Azul de Metileno
4.
Environ Res ; 232: 116319, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37271436

RESUMEN

This current study aims to develop a unique biomaterial that can fight against oxidative stress and microbial infections without causing any harm. As a result, an easy-to-make, environment-friendly, long-lasting, and non-toxic copper oxide nanoparticle (CuONP) was synthesized using an edible mushroom Pleurotus citrinopileatus extract. The UV-vis spectroscopy analyses reflected a sharp absorbance peak at 250 nm. The FTIR, XRD, SEM, HR-TEM, and EDX instrumental tools were used to characterize the myco-produced CuONPs. The face-centred cubic (FCC) CuONPs were found to have diffraction peaks at the planes of (110), (002), (111), (112), (020), (202), (113), (310), (220), and (004). The HR-TEM result showed the particles had a spherical structure and an average nanoparticles size of 20 nm. The antimicrobial activity results expressed the broad spectrum of antibacterial effect and the better growth inhibition zone was recorded in P. aeruginosa (8.3 ± 0.1), E. coli (7.4 ± 0.3), K. pneumoniae (7.2 ± 0.1), S. aureus (7.1 ± 0.3), S. pneumoniae (6.3 ± 0.2), and B. cereus (6.2 ± 0.3 mm). The cytotoxicity efficacy of myco-synthesized CuONPs tested against a cancer cell line (HT-29) observed the best result in low doses of mushroom extract (45.62 µg/mL). Based on the outcome of the study suggests that the mycosynthesized CuONPs using Pleurotus mushroom extract might serve as an alternative agent for biomedical applications in the near future.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Pleurotus , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/química , Staphylococcus aureus , Escherichia coli , Cobre/química , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química , Óxidos , Espectroscopía Infrarroja por Transformada de Fourier
5.
Mikrochim Acta ; 190(5): 197, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-37120457

RESUMEN

A highly sensitive 4-cyanophenol (4-CP) sensor was fabricated using multi-walled carbon nanotube (MWCNT)-embedded dual-microporous polypyrrole nanoparticle-modified screen-printed carbon electrodes (SPCE/DMPPy/MWCNT). The well-defined dual pores of DMPPy and MWCNT (~ 0.53 and ~ 0.65 nm) acted as good analyte absorption agents (shortening the ion diffusion path) and conducting agents (reducing the internal electron-transfer resistance). This enhanced electrical conductivity resulted in the improved electro-oxidation of 4-CP. A higher sensitivity (19.0 µA µM-1 cm-2) and lower limit of detection (0.8 nM) were achieved with a wide detection range of 0.001-400 µM (R2 = 0.9988). The proposed sensor exhibited excellent recovery of 4-CP in real-world samples. Therefore, the SPCE/DMPPy/MWCNT sensor is regarded highly suitable for rapidly detecting 4-CP.

6.
Nanotechnology ; 32(49)2021 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-34399410

RESUMEN

Hydrogen has been considered as one of the most promising alternative energy source to solve the future energy demands due to its high energy capacity and emission-free character. The generation of hydrogen from non-fossil sources is necessary for the sustainable development of human life on this planet. The hydrolysis of sodium borohydride can quickly produce a large amount of hydrogenin situand on-demand in the presence of the catalyst, which can be used as an alternative energy source. So, it is crucial to fabricate the highly efficient, robust, and economical catalyst for the production of hydrogen via hydrolysis of sodium borohydride. Herein, a facile and efficient approach for the synthesis of metal-functionalized reduced graphene oxide for the production of hydrogen at room temperature was used. Moreover, the synthesized catalyst has also been tested in the field of environmental catalysis for the reduction of toxic 4-nitrophenol to valuable 4-aminophenol in the presence of sodium borohydride. The enhanced activity of prepared metal-functionalized reduced graphene oxide is ascribed to a strong affinity between Fe-NXand reduced graphene oxide which facilitates electron transfer as well as synergistic effect. Overall, this work presents a crucial procedure for green chemistry reactions when a carbonaceous material is selected as a catalyst.

7.
Mikrochim Acta ; 188(7): 233, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-34145512

RESUMEN

Well-defined crystal structures of Pd-doped WO3 nanorods were assembled on graphitic carbon sheets (Pd-WO3/g-C3N4) for ultrasensitive detection of paraoxon-ethyl (PEL) using an electrochemical method. The electrochemical behavior of PEL on the Pd-WO3/g-C3N4 hybrid composite was investigated using cyclic voltammetry (CV) and amperometric techniques. The Pd-WO3 crystallite was seen to modify the kinetics of g-C3N4, which improved the reduction/redox peak currents of PEL at the Pd-WO3/g-C3N4 composite compared to those of the g-C3N4 and WO3/g-C3N4-modified electrode. Moreover, the π-π interaction and hydrogen bond between the PEL and Pd-WO3/g-C3N4 composite improved the charge-transfer properties. The Pd-WO3/g-C3N4 hybrid composite was therefore able to obtain an enhanced sensitivity (3.70 ± 0.05 µA µM-1 cm-2) and low detection limit (0.03 nM; S/N = 3) with a wide range of linear concentrations (0.01-60 and 80-900.0 ± 5 µM) at applied potential of - 0.63 V (vs. Ag/AgCl). The detection of PEL in agricultural water and soil samples was successfully demonstrated with satisfactory RSD of 2.5 to 3.1% and recovery results of 97 to 102%, respectively.

8.
Mikrochim Acta ; 188(4): 135, 2021 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-33759064

RESUMEN

We prepared, for the first time, carbon aerogels support on Pd-WO3 nanorods (CAs/Pd-WO3) hybrid nanocomposite via sol-gel and microwave-assisted methods. The as-prepared CAs/Pd-WO3-modified electrode was used as effective electrocatalyst for nanomolar level detection of mesalazine (MSA). The typical porous nature of carbon aerogels effectively prevented the aggregation of Pd-doped WO3 nanorods and increased the electrochemically active surface area. In addition, the Pd-WO3 nanointerface provides intrinsic improvement of the electrocatalytic activity and stability for the electrochemical oxidation process, and the interconnected conducting network of the porous surfaces of CAs accelerated rapid electron transport at the working electrode. The synergistic effect of the CAs/Pd-WO3 architecture has excellent electrocatalytic activity for the detection of MSA with high sensitivity of 2.403 ± 0.004 µA µM-1 cm-2, low detection limit of 0.8 ± 0.3 nM and wide linear response from 0.003-350 µM at a low applied potential of 0.30 V vs. Ag|AgCl. Satisfactory results were observed for its analytical performance in detecting MSA in human blood serum and urine samples, and recoveries ranged from 98.8 to 100.4%. We believe that the architecture of the modified CAs/Pd-WO3 electrocatalysts can be effectively used in clinical applications for the detection of MSA.

9.
Int Arch Allergy Immunol ; 175(1-2): 16-25, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29339659

RESUMEN

BACKGROUND: The transcription factor nuclear factor (NF)-κB plays a pivotal role in the development of allergic airway inflammation. However, the mechanism of NF-κB activation in asthma remains to be elucidated. METHODS: CK2α activation was assessed by CK2α phosphorylation and protein expression. Airway levels of histamine and cytokines were determined by ELISA. We used 2 (active and passive) forms of allergic pulmonary inflammation models. In the active form, the animals were immunized with ovalbumin (OVA) intraperitoneally, followed by an airway challenge with OVA. In the passive form, the animals were passively sensitized by intratracheal instillation with either anti-OVA IgE or anti-OVA IgG, followed by an airway challenge with OVA. The role of NADPH oxidase (NOX) in CK2α activation was assessed using NOX2-/- and NOX4-/- mice because NOX2 and NOX4 contribute to many inflammatory diseases. RESULTS: The second airway challenge increased CK2α phosphorylation and protein expression in airway epithelial cells as well as nuclear translocation of the p50 and p65 subunits of NF-κB, all of which were inhibited by the CK2α inhibitor 4,5,6,7-tetrabromobenzotriazole and the antioxidant N-acetyl-L-cysteine. CK2α phosphorylation and protein expression were significantly impaired in NOX2-/-, but not in NOX4-/-, mice. Induction of passive sensitization using anti-OVA IgE activated neither CK2α nor NF-κB. In contrast, induction of passive sensitization using anti-OVA IgG activated both CK2α and NF-κB. CONCLUSIONS: These data suggest that Fcγ receptor/reactive oxygen species/CK2α is a key inducer of NF-κB activation in airway epithelial cells in a murine model of asthma.


Asunto(s)
Asma/metabolismo , Quinasa de la Caseína II/metabolismo , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/metabolismo , FN-kappa B/metabolismo , Alérgenos/inmunología , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Histamina/metabolismo , Humanos , Inmunización , Inmunoglobulina E/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasa 2/genética , NADPH Oxidasa 4/genética , Ovalbúmina/inmunología , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Receptores de IgG/metabolismo
10.
Int Arch Allergy Immunol ; 171(1): 61-70, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27838690

RESUMEN

BACKGROUND: Cytosolic phospholipase A2 (cPLA2) plays a key role in the development of late-phase anaphylaxis. L-Glutamine (Gln), a nonessential amino acid, has anti-inflammatory activity via inhibiting cPLA2. METHODS: We used a penicillin-induced murine model of anaphylaxis, and late-phase anaphylaxis was quantified by measuring the increase in the hematocrit (Ht) value. Various inhibitors, small interfering RNA, and knockout mice were used in inhibition experiments. Phosphorylation and protein expression of cPLA2, ERK, and MAPK phosphatase 1 (MKP-1) were detected by Western blotting. RESULTS: Leukotriene (LT) B4 was found to be another potent inducer of late-phase anaphylaxis besides the known mediator platelet-activating-factor (PAF). Gln efficiently prevented late-phase anaphylaxis when it was administered up to 3 h after challenge injection via inhibiting cPLA2. Inhibition studies indicated that p38 MAPK was the major upstream regulator of cPLA2. Gln dephosphorylated p38 and cPLA2 via up-regulating the negative regulator of p38 MAPK, i.e., MKP-1 protein. MKP-1 blockade abrogated all the effects of Gln. CONCLUSION: Of the cPLA2 metabolites, PAF and LTB4 play a key role in the development of late-phase anaphylaxis, and Gln prevents the reaction via MKP-1-dependent deactivation of cPLA2.


Asunto(s)
Anafilaxia/inmunología , Anafilaxia/metabolismo , Fosfatasa 1 de Especificidad Dual/metabolismo , Glutamina/farmacología , Fosfolipasas A2 Citosólicas/metabolismo , Anafilaxia/genética , Anafilaxia/prevención & control , Animales , Modelos Animales de Enfermedad , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Leucotrieno B4/sangre , Ratones , Ratones Noqueados , Fosfolipasas A2 Citosólicas/genética , Fosforilación/efectos de los fármacos , Factor de Activación Plaquetaria/metabolismo , ARN Interferente Pequeño/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
11.
Nanotechnology ; 26(13): 135705, 2015 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-25760426

RESUMEN

This study proposes a novel method of improving the electrical conductivity of silver nanowires (NWs)-networked films for the application of transparent conductive electrodes. We applied Cs-added TiO2 (TiO2:Cs) nanoparticles onto Ag NWs, which caused the NWs to be neatly welded together through local melting at the junctions, according to our transmission and scanning electron microscopy analyses. Systematic comparison of the sheet resistance of the samples reveals that these welded NWs yielded a significant improvement in conductivity. OLED devices, fabricated by using the NW film planarized via embedding the wires into PMMA, demonstrated device performance was comparable with the reference sample with indium tin oxide electrode.

12.
Phys Chem Chem Phys ; 17(26): 16791-7, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26059493

RESUMEN

The electrical stabilities of low-voltage organic field-effect transistors (OFETs) were improved by applying graftable fluorinated polymer (gPFS) layers onto poly(4-vinyl phenol)-based cross-linked dielectrics (cPVP). As a result, a smooth and hydrophobic surface was formed, and the dielectric film displayed a low-leakage current density. The chemisorbed gPFS groups enabled the solution processing of an overlying 5,11-bis(triethylsilylethynyl)anthradithiophene semiconductor, which formed favorable terrace-like crystalline structures after solvent annealing. The top-contact OFETs showed superior operational stability compared to cPVP-based OFETs. Hysteresis was negligible, and the off-current of the transfer curve was one order of magnitude lower than that obtained from cPVP-based OFETs. The threshold voltage shift measured after a sustained gate bias stress for 1 h decreased significantly after introduction of the hydrophobic gPFS treatment; the energetic barrier to creating charge trapping sites increased, and the trap distribution narrowed, as supported by the stretched exponential function model.

13.
Immunology ; 143(1): 21-32, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24628121

RESUMEN

Platelet-activating factor (PAF) promotes tumour metastasis via activation of the transcription factor nuclear factor-κB (NF-κB). We here investigated the role of the protein kinase CK2 (formerly Casein Kinase 2 or II) in PAF-induced NF-κB activation and tumour metastasis, given that PAF has been reported to increase CK2 activity, and that CK2 plays a key role in NF-κB activation. PAF increased CK2 activity, phosphorylation and protein expression in vivo as well as in vitro. CK2 inhibitors inhibited the PAF-mediated NF-κB activation and expression of NF-κB-dependent pro-inflammatory cytokines and anti-apoptotic factors. Pre-treatment with the antioxidant N-Acetyl-L-Cysteine (NAC) resulted in a significant inhibition in PAF-induced enhancement of CK2 activity, phosphorylation and protein expression in vivo as well as in vitro. H2 O2 and known reactive oxygen species inducers, lipopolysaccharide (LPS) and tumour necrosis factor-α (TNF-α) enhanced CK2 activity, phosphorylation and protein expression, which was again inhibited by antioxidant. PAF, LPS and TNF-α induced increased CK2 activity, phosphorylationand protein expression, which were inhibited by p38 inhibitor. PAF, LPS or TNF-α increased pulmonary metastasis of B16F10, which was inhibited by antioxidants, CK2 inhibitor and p38 inhibitor. Our data suggest that (i) reactive oxygen species activate CK2 via p38, which, in turn, induces NF-κB activation, and (ii) PAF, LPS and TNF-α increase pulmonary tumour metastasis via the induction of the reactive oxygen species (ROS)/p38/CK2/NF-κB pathway.


Asunto(s)
Quinasa de la Caseína II/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , FN-kappa B/metabolismo , Factor de Activación Plaquetaria/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Western Blotting , Modelos Animales de Enfermedad , Ensayo de Cambio de Movilidad Electroforética , Activación Enzimática/fisiología , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Invasividad Neoplásica/patología , Reacción en Cadena en Tiempo Real de la Polimerasa
14.
J Immunol ; 189(11): 5139-46, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23109722

RESUMEN

Neutrophils are inflammatory cells that may contribute in a crucial way to the pathophysiology of steroid-resistant severe asthma. We previously reported that the nonessential amino acid l-glutamine (Gln) suppressed the recruitment of neutrophils into the airway in a murine model of asthma. In this study, we investigated the mechanisms by which Gln exerts beneficial effects in airway neutrophilia. We used the model we previously developed, which is suitable for examining sequential early asthmatic events, including neutrophil infiltration. Gln suppressed airway neutrophilia in a CXC chemokine-independent way. Airway neutrophilia was associated with cytosolic phospholipase A(2) (cPLA(2)) and 5-lipoxygenase (5-LO) activities. p38 MAPK, the upstream pathway of cPLA(2) and 5-LO, played a key role in inducing airway neutrophilia. Gln inhibited not only the phosphorylation of cPLA(2) and p38 MAPK but also leukotriene B(4) levels in the airways. Gln induced the early induction of MAPK phosphatase-1 (MKP-1) protein, a negative regulator of p38. MKP-1 small interfering RNA abrogated all the effects of Gln. Our results suggest that pathways involving p38/cPLA(2)/5-LO have a major role in airway neutrophilia. Gln suppresses airway neutrophilia via inhibiting p38 MAPK and its downstream pathways in an MKP-1-dependent way, which may provide a novel therapeutic strategy for pulmonary neutrophilic inflammatory diseases.


Asunto(s)
Fosfatasa 1 de Especificidad Dual/inmunología , Glutamina/uso terapéutico , Inflamación/tratamiento farmacológico , Neutrófilos/efectos de los fármacos , Fosfolipasas A2/inmunología , Sistema Respiratorio/efectos de los fármacos , Animales , Araquidonato 5-Lipooxigenasa/genética , Araquidonato 5-Lipooxigenasa/inmunología , Citosol/efectos de los fármacos , Citosol/inmunología , Citosol/metabolismo , Fosfatasa 1 de Especificidad Dual/genética , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/inmunología , Glutamina/administración & dosificación , Glutamina/inmunología , Inflamación/genética , Inflamación/inmunología , Inflamación/metabolismo , Leucotrieno B4/antagonistas & inhibidores , Leucotrieno B4/inmunología , Ratones , Ratones Endogámicos BALB C , Neutrófilos/inmunología , Neutrófilos/metabolismo , Inhibidores de Fosfolipasa A2 , Fosfolipasas A2/genética , Fosforilación/efectos de los fármacos , Fosforilación/inmunología , Sistema Respiratorio/inmunología , Sistema Respiratorio/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/inmunología
15.
J Colloid Interface Sci ; 657: 229-239, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38039883

RESUMEN

Electrolysis in seawater is a low-cost but difficult method of producing hydrogen. Herein, self-assembled hierarchical three-dimensional (3D) porous trimetallic palladium-iron and cobalt oxide anchored on a cheap and high surface area nickel foam (NF) (PdFeCo3-xO4/NF) were synthesized using a simple and low-cost impregnation-hydrothermal and thermal reduction strategy. The as-fabricated PdFeCo3-xO4/NF electrode showed both superhydrophilic and superaerophobic properties, which favored the fat removal of oxygen bubbles from the electrode surface owing to the close interaction between the electrode and electrolyte. Furthermore, the significant synergistic effect of trimetallics and the NF-matrix resulted in substantially enhanced oxygen evolution reaction (OER) intrinsic activity. The self-assembled PdFeCo3-xO4/NF catalyst exhibited critical low overpotentials of 300 and 340 mV to achieve an extremely large current density of 100 mA cm-2 in 1 M KOH solution and 1 M KOH seawater. Cell voltages as low as 1.44 and 1.51 V were required to drive 10 mA cm-2 in alkaline solution and seawater electrolytes for the full cell overall water splitting performance. This work suggests a promising strategy for developing next-generation electrocatalysts appropriate for natural seawater with cost-effective.

16.
Int Arch Allergy Immunol ; 160(2): 173-83, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23018605

RESUMEN

BACKGROUND: Nonspecific airway hyperresponsiveness (AHR) is one of the cardinal features of bronchial asthma. Early AHR is caused by chemical mediators released from pulmonary mast cells activated in an IgE-dependent way. However, the mechanism of late AHR remains unclear. METHODS: Features of airway allergic inflammation were analyzed, including antigen-induced AHR, using a murine model of asthma. The model was suitable for examining the sequential early molecular events occurring after the initial airway exposure to antigen. RESULTS: AHR increased at 10-12 h after airway challenge, followed by the second-phase response, which was larger and broader in resistance at 18-30 h. Pretreatment of sensitized animals with anti-tumor necrosis factor (TNF) before airway challenge or induction of allergic asthma in TNF(-/-) mice resulted in abrogation of the first-phase late AHR. Intratracheal instillation of TNF induced a single peak of AHR at 10 h. IgE and IgG immune complexes induced the development of the first-phase late AHR by TNF production. Pretreatment with cytosolic phospholipase inhibitor and 5-lipoxygenase inhibitors abolished the first-phase late AHR as well as the leukotriene B(4) levels in the airway. CpG-oligodeoxynucleotide (ODN) pretreatment reduced airway levels of Th2 cytokines, eosinophil infiltration and second-phase late AHR. However, CpG-ODN did not reduce TNF levels or the magnitude of first-phase late AHR. CONCLUSION: Biphasic late AHR occurs in a murine model of asthma. First- and second-phase late AHR is caused by TNF and Th2 response, respectively.


Asunto(s)
Asma/inmunología , Hiperreactividad Bronquial/inmunología , Alérgenos/inmunología , Animales , Asma/fisiopatología , Hiperreactividad Bronquial/fisiopatología , Citocinas/inmunología , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Immunoblotting , Inflamación/inmunología , Inflamación/fisiopatología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina/inmunología , Células Th2/inmunología , Factor de Necrosis Tumoral alfa/inmunología
17.
J Anesth ; 27(4): 563-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23455773

RESUMEN

PURPOSE: This prospective, observational study was performed to examine the hypothesis that if conventional 7-cm head elevation is applied, laryngoscopy is more difficult for patients with anteroposterior chest diameter (chest AP diameter) outside the average range (≥17.7 or ≤14.7 cm). METHODS: Chest AP diameter at the sternal notch were measured preoperatively. All patients were placed on a surgical bed with an incompressible 7-cm pillow. During laryngoscopy, the laryngeal view was graded by use of the Cormack-Lehane classification. Difficult visualization of the larynx (DVL) was defined as a grade 3 or 4 view. RESULTS: DVL was observed for 49 patients (18.2 %). Differences between measured chest AP diameter for each patient and the calculated median value were used for statistical analysis. In univariate analysis, the difference between chest AP diameter and the median value was significantly related to DVL. Logistic regression analysis confirmed that the difference between chest AP diameter and the median value was an independent predictor of DVL (odds ratio, 3.900; 95 % confidence interval, 2.371-6.415; p < 0.001). Receiver operating characteristic curve analysis showed that this test with a test threshold of 1.5 cm had reasonable diagnostic accuracy (area under the curve of 0.748). CONCLUSION: When using a standard pillow size of 7 cm, chest AP diameter above or below the average range (≥17.7 or ≤14.7 cm) was a strong predictor of DVL for apparently normal-sized patients. In such cases, modification of pillow height should be considered.


Asunto(s)
Laringoscopía/métodos , Obesidad/fisiopatología , Tamaño Corporal , Femenino , Humanos , Intubación Intratraqueal/métodos , Laringe/anatomía & histología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Morbilidad , Postura , Estudios Prospectivos , Tórax/anatomía & histología
18.
Micromachines (Basel) ; 14(10)2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37893344

RESUMEN

Recently, two-dimensional (2D) MXenes materials have received enormous attention because of their excellent physiochemical properties such as high carrier mobility, metallic electrical conductivity, mechanical properties, transparency, and tunable work function. MXenes play a significant role as additives, charge transfer layers, and conductive electrodes for optoelectronic applications. Particularly, titanium carbide (Ti3C2Tx) MXene demonstrates excellent optoelectronic features, tunable work function, good electron affinity, and high conductivity. The Ti3C2Tx has been widely used as electron transport (ETL) or hole transport layers (HTL) in the development of perovskite solar cells (PSCs). Additionally, Ti3C2Tx has excellent electrochemical properties and has been widely explored as sensing material for the development of electrochemical biosensors. In this review article, we have summarized the recent advances in the development of the PSCs using Ti3C2Tx MXene as ETL and HTL. We have also compiled the recent progress in the fabrication of biosensors using Ti3C2Tx-based electrode materials. We believed that the present mini review article would be useful to provide a deep understanding, and comprehensive insight into the research status.

19.
Biosensors (Basel) ; 13(11)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37998142

RESUMEN

L-tryptophan (L-TRP) is an essential amino acid responsible for the establishment and maintenance of a positive nitrogen equilibrium in the nutrition of human beings. Therefore, it is vital to quantify the amount of L-tryptophan in our body. Herein, we report the MoS2/S@g-CN-modified glassy carbon electrode for the electrochemical detection of L-tryptophan (L-TRP). The MoS2/S@g-CN composite was successfully synthesized using an efficient and cost-effective hydrothermal method. The physical and chemical properties of the synthesized composite were analyzed using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray analysis (EDX). The crystallite size of the composite was calculated as 39.4 nm, with porous balls of MoS2 decorated over the S@g-CN surface. The XPS spectrum confirmed the presence of Mo, S, O, C, and N elements in the sample. The synthesized nanocomposite was further used to modify the glassy carbon (GC) electrode (MoS2/S@g-CN/GC). This MoS2/S@g-CN/GC was used for the electrochemical detection of L-TRP using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. For the purpose of comparison, the effects of the scanning rate and the concentration of L-TRP on the current response for the bare GC, S@g-CN/GC, MoS2/GC, and MoS2/S@g-CN/GC were studied in detail. The MoS2/S@g-CN-modified GC electrode exhibited a rational limit of detection (LoD) of 0.03 µM and a sensitivity of 1.74 µA/ µMcm2, with excellent stability, efficient repeatability, and high selectivity for L-TRP detection.


Asunto(s)
Grafito , Humanos , Grafito/química , Triptófano/análisis , Molibdeno , Carbono/química , Electrodos , Técnicas Electroquímicas/métodos
20.
Biosensors (Basel) ; 13(2)2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36831961

RESUMEN

Electrochromic technologies that exhibit low power consumption have been spotlighted recently. In particular, with the recent increase in demand for paper-like panel displays, faster coloration time has been focused on in researching electrochromic devices. Tungsten trioxide (WO3) has been widely used as an electrochromic material that exhibits excellent electrochromic performance with high thermal and mechanical stability. However, in a solid film-type WO3 layer, the coloration time was long due to its limited surface area and long diffusion paths of lithium ions (Li-ions). In this study, we attempted to fabricate a fibrous structure of WO3@poly(ethylene oxide) (PEO) composites through electrospinning. The fibrous and porous layer showed a faster coloration time due to a short Li-ion diffusion path. Additionally, PEO in fibers supports Li-ions being quickly transported into the WO3 particles through their high ionic conductivity. The optimized WO3@PEO fibrous structure showed 61.3 cm2/C of high coloration efficiency, 1.6s fast coloration time, and good cycle stability. Lastly, the electrochromic device was successfully fabricated on fabric using gel electrolytes and a conductive knitted fabric as a substrate and showed a comparable color change through a voltage change from -2.5 V to 1.5 V.


Asunto(s)
Dispositivos Electrónicos Vestibles , Transporte Biológico , Difusión , Conductividad Eléctrica , Electrodos , Litio
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