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1.
Mol Immunol ; 170: 60-75, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38626622

RESUMEN

Liver diseases caused by viral infections, alcoholism, drugs, or chemical poisons are a significant health problem: Liver diseases are a leading contributor to mortality, with approximately 2 million deaths per year worldwide. Liver fibrosis, as a common liver disease characterized by excessive collagen deposition, is associated with high morbidity and mortality, and there is no effective treatment. Numerous studies have shown that the accumulation of mast cells (MCs) in the liver is closely associated with liver injury caused by a variety of factors. This study investigated the relationship between MCs and carbon tetrachloride (CCl4)-induced liver fibrosis in rats and the effects of the MC stabilizers sodium cromoglycate (SGC) and ketotifen (KET) on CCl4-induced liver fibrosis. The results showed that MCs were recruited or activated during CCl4-induced liver fibrosis. Coadministration of SCG or KET alleviated the liver fibrosis by decreasing SCF/c-kit expression, inhibiting the TGF-ß1/Smad2/3 pathway, depressing the HIF-1a/VEGF pathway, activating Nrf2/HO-1 pathway, and increasing the hepatic levels of GSH, GSH-Px, and GR, thereby reducing hepatic oxidative stress. Collectively, recruitment or activation of MCs is linked to liver fibrosis and the stabilization of MCs may provide a new approach to the prevention of liver fibrosis.


Asunto(s)
Tetracloruro de Carbono , Cromolin Sódico , Cirrosis Hepática , Hígado , Mastocitos , Animales , Mastocitos/metabolismo , Mastocitos/inmunología , Mastocitos/efectos de los fármacos , Tetracloruro de Carbono/toxicidad , Ratas , Masculino , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/inmunología , Cirrosis Hepática/inducido químicamente , Cromolin Sódico/farmacología , Hígado/patología , Hígado/metabolismo , Hígado/efectos de los fármacos , Factor de Crecimiento Transformador beta1/metabolismo , Ratas Sprague-Dawley , Cetotifen/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/inmunología , Estrés Oxidativo/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
2.
Adv Sci (Weinh) ; : e2401667, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627981

RESUMEN

Constructing heterojunctions with vacancies has garnered substantial attention in the field of piezo-photocatalysis. However, the presence of interfacial vacancies can serve as charge-trapping sites, leading to the localization of electrons and hindering interfacial charge transfer. Herein, dual oxygen vacancies in the NiFe-layered double hydroxide and Bi2MoO6- x induced interfacial bonds have been designed for the piezo-photocatalytic N2 oxidation to NO3 -. Fortunately, it achieves sensational nitric acid production rates (7.23 mg g-1 h-1) in the absence of cocatalysts and sacrificial agents, which is 6.03 times of pure Bi2MoO6 that under ultrasound and light illumination. Theoretical and experimental results indicate that interfacial bonds act as "charge bridge" and "strain center" to break the carrier local effect and negative effects with piezocatalysis and photocatalysis for promoting exciton dissociation and charge transfer. Moreover, the strong electronic interaction of the interfacial bond induces internal reconstruction under ultrasound for promoting the local polarization and adsorption of N2, which accelerates the fracture of the N≡N bonds and reduces the activation energy of the reaction. The research not only establishes a novel approach for optimizing the combined effects of piezo-catalysis and photocatalysis, but also achieves equilibrium between the synergistic impacts of vacancies and heterojunctions.

3.
Toxicol Lett ; 394: 76-91, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38428544

RESUMEN

Aristolochic acid I (AAI), a component of aristolochic acids, can be converted to the toxic metabolite Aristolactam I (ALI) in vivo which forms aristolactam-nitrenium with delocalized positive charges. It is widely accepted that delocalized lipophilic cations can accumulate in mitochondria due to the highly negatively charged microenvironment of the mitochondrial matrix, but the uptake of ALI by mitochondria is not known. In this study, the cell uptake and mitochondrial localization of ALI, and its subsequent impact on mitochondrial function were investigated. Results show that ALI can rapidly penetrate HK-2 cells without relying on organic anion transporters 1/3 (OAT1/3). The cellular distribution of ALI was found to align with the observed distribution of a mitochondria-selective dye in HK-2 cells. Furthermore, the cell uptake and mitochondrial uptake of ALI were both inhibited by carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone, which induces mitochondrial membrane depolarization. These results suggest that ALI is selectively taken up by mitochondria. Consequently, mitochondrial dysfunction was observed after treatment with ALI. It should be noted that inhibiting OAT1/3 could result in an increased exposure of ALI in vivo and cause more seriously nephrotoxicity. In conclusion, this research reports the mitochondrial uptake of ALI and provides new insight on potential strategies for protection against AAI-induced nephrotoxicity.


Asunto(s)
Ácidos Aristolóquicos , Ácidos Aristolóquicos/toxicidad , Mitocondrias
4.
J Colloid Interface Sci ; 656: 528-537, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38007944

RESUMEN

Vacancies engineering has sparked a huge interest in enhancing photocatalytic activity, but monovacancy simultaneously conducts as either electron or hole acceptor and redox reaction, worsening charge transfer and catalytic performance. Here, the concept of electronic inversion has been proposed through the simultaneous introduction of surface oxygen and S vacancies in CdIn2S4 (OSv-CIS). Consequently, under mild conditions, the well-designed OSv-CIS-200 demonstrated a strong rate of N-benzylidenebenzylamine production (2972.07 µmol g-1 h-1) coupled with Hydrogen peroxide (H2O2) synthesis (2362.33 µmol g-1 h-1) (PIH), which is 12.4 times higher than that of CdIn2S4. Density functional theory (DFT) simulation and characterization studies demonstrate that oxygen is introduced into the lattice on the surface of the material, reversing the charge distribution of the S vacancy and enhancing the polarity of the total charge distribution. It not only provides a huge built-in electric field (BEF) for guiding the orientation of the charge transfer, but also acts as a long-distance active site to accelerate reaction and prevent H2O2 decomposition. Our work offers a straightforward connection between the atomic defect and intrinsic properties for designing high-efficiency materials.

5.
Chemosphere ; 345: 140505, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37866493

RESUMEN

With the rapid development of aquaculture, the production of oyster shells has surged, posing a potential threat to the environment. While oyster shell powder is widely recognized for its inherent alkalinity and rich calcium carbonate content, making it a superior soil conditioner, its role in organic solid waste composting remains underexplored. To investigate the effects of varying concentrations of oyster shell powder on compost maturation and calcium activation, this study employed thermophilic co-composting with acidic sugar residue and bean pulp, incorporating 0% (control), 10% (T1), 20% (T2), 30% (T3), and 40% (T4) oyster shell powder. Findings revealed that appropriate proportions of oyster shell powder significantly enhance temperature stability during composting and elevate maturation levels, notably reducing ammonia emissions between 62.5% and 76.7%. Intriguingly, the calcium in the oyster shell powder was significantly activated during composting, with the 40% addition group achieving the highest calcium activation rate of 48.5%. In summation, the inclusion of oyster shell powder not only optimizes the composting process but also efficiently activates the calcium, resulting in an alkaline organic-inorganic composite soil conditioner with high exchangeable calcium content. This research holds significant implications for promoting the high-value utilization of oyster shells.


Asunto(s)
Compostaje , Ostreidae , Animales , Residuos Sólidos , Calcio , Polvos , Suelo/química , Carbonato de Calcio , Calcio de la Dieta
6.
Materials (Basel) ; 16(13)2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37444875

RESUMEN

In this study, a novel hybrid additive and subtractive manufacturing method using pulsed arc plasma (PAP-HASM) was developed to better integrate additive and subtractive processes. The PAP-HASM process is based on the flexible application of pulsed arc plasma. In this PAP-HASM method, wire arc additive manufacturing using pulsed arc plasma (PAP-WAAM) and dry electrical discharge machining (EDM) milling were used as additive and subtractive techniques, respectively; both are thermal machining processes based on pulsed arc plasma, and both are dry machining techniques requiring no working fluids. The PAP-HASM can be easily realized by only changing the pulsed power supply and tool electrodes. A key technological challenge is that the recast layer on the part surface after dry EDM milling may have a detrimental effect on the component fabricated by PAP-HASM. Here, the hybrid manufacturing method developed in this study was validated with commonly used 316L stainless steel. Preliminary experimental results showed that the PAP-HASM specimens exhibited excellent tensile properties, with an ultimate tensile strength of 539 ± 8 MPa and elongation of 46 ± 4%, which were comparable to the PAP-WAAM specimens. The recast layer on the surface after dry EDM milling has no significant detrimental effect on the mechanical properties of the parts fabricated by PAP-HASM. In addition, compared with components fabricated by PAP-WAAM, those fabricated by PAP-HASM showed significantly better surface roughness.

7.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37446016

RESUMEN

Renal fibrosis is relentlessly progressive and irreversible, and a life-threatening risk. With the continuous intake of a high-purine diet, hyperuricemia has become a health risk factor in addition to hyperglycemia, hypertension, and hyperlipidemia. Hyperuricemia is also an independent risk factor for renal interstitial fibrosis. Numerous studies have reported that increased mast cells (MCs) are closely associated with kidney injury induced by different triggering factors. This study investigated the effect of MCs on renal injury in rats caused by hyperuricemia and the relationship between MCs and renal fibrosis. Our results reveal that hyperuricemia contributes to renal injury, with a significant increase in renal MCs, leading to renal fibrosis, mitochondrial structural disorders, and oxidative stress damage. The administration of the MCs membrane stabilizer, sodium cromoglycate (SCG), decreased the expression of SCF/c-kit, reduced the expression of α-SMA, MMP2, and inhibited the TGF-ß1/Smad2/3 pathway, thereby alleviating renal fibrosis. Additionally, SCG reduced renal oxidative stress and mitigated mitochondrial structural damage by inhibiting Ang II production and increasing renal GSH, GSH-Px, and GR levels. Collectively, the recruitment of MCs, activation of the TGF-ß1/Smad2/3 pathway, and Ang II production drive renal oxidative stress, ultimately promoting the progression of renal fibrosis in hyperuricemic rats.


Asunto(s)
Hiperuricemia , Enfermedades Renales , Ratas , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Hiperuricemia/metabolismo , Mastocitos/metabolismo , Transducción de Señal , Enfermedades Renales/metabolismo , Riñón/metabolismo , Fibrosis , Estrés Oxidativo
8.
Luminescence ; 38(9): 1562-1571, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37309260

RESUMEN

A series of Mn4+ -doped and Mn4+ ,K+ -co-doped Ba2 LaTaO6 (BLT) double-perovskite phosphors was synthesized using a high-temperature solid-state reaction. The phase purity and luminescence properties were also studied. The optimum doping concentration of Mn4+ and K+ was obtained by investigating the photoluminescence excitation spectra and photoluminescence emission spectra. The comparison of BLT:Mn4+ phosphors with and without K+ ions shows that the photoluminescence intensity of K+ -doped phosphors was greatly enhanced. This is because there was a charge difference when Mn4+ ions were doped with Ta5+ ions in BLT. Mn4+ -K+ ion pairs were formed after doping K+ ions, which hinders the nonradiative energy transfer between Mn4+ ions. Therefore, the luminescence intensity, quantum yield, and thermal stability of phosphors were enhanced. The electroluminescence spectra of BLT:Mn4+ and BLT:Mn4+ ,K+ were measured. The spectra showed that the light emitted from the phosphors corresponded well with chlorophyll a and phytochrome PR . The results show that the BLT:Mn4+ ,K+ phosphors had good luminescence properties and application prospects and are ideal materials for plant-illuminated red phosphors.


Asunto(s)
Iluminación , Metales Alcalinos , Clorofila A , Luminiscencia , Iones
9.
Nanomaterials (Basel) ; 13(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36770390

RESUMEN

After the discovery of bulk photovoltaic effect more than half a century ago, ferro-electrical and magneto-optical experiments have provided insights into various related topics, revealing above bandgap open voltages and non-central symmetrical current mechanisms. However, the nature of the photon-generated carriers responses and their microscopic mechanisms remain unclear. Here, all-inorganic perovskite Bi0.85Gd0.15Fe1-xMnxO3 thin films were prepared by a sol-gel process and the effects of Gd and Mn co-doped bismuth ferrites on their microtopography, grain boundries, multiferroic, and optical properties were studied. We discovered a simple "proof of principle" type new method that by one-step measuring the leakage current, one can demonstrate the value of photo generated current being the sum of ballistic current and shift current, which are combined to form the so-called bulk photovoltaic current, and can be related to the prototype intrinsic properties such as magneto-optical coupling and ferroelectric polarization. This result has significant potential influence on design principles for engineering multiferroic optoelectronic devices and future photovoltaic industry development.

10.
Toxicology ; 483: 153387, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36464070

RESUMEN

The accumulation of uric acid (UA) in the body can lead to the occurrence of hyperuricemia or uric acid nephropathy. Mast cells (MCs) increase oxidative stress and release renin to promote the production of Ang II. The aim of this study was to investigate the effect of UA on MCs in rat kidneys and the association between MCs and renal injury. Our results show that UA accumulation in the kidney stimulated the degranulation of MCs and the release of renin to promote Ang II production, resulting in renal oxidative stress, mitochondrial structural damage, and microvascular system damage. The expression of urate-related transporters was regulated by the UA level and serum urinary toxins levels were substantially elevated in hyperuricemia. Administration of the MCs membrane stabilizer sodium cromoglycate (SCG) or the angiotensin receptor antagonist Valsartan decreased the production of renin and Ang II and relieved renal oxidative stress, mitigated mitochondrial structural damage and microvascular system damage, and promoted the excretion of UA and urinary toxins by increasing the expression of urate-related transporters. These results demonstrate that the accumulation of UA in the kidney can trigger the degranulation of MCs and promote the development of renal oxidative stress. Administration of SCG and Valsartan ameliorated UA-induced renal injury by inhibiting MCs degranulation and reducing renal oxidative stress by inhibiting renin and Ang II production and accelerating renal clearance of UA and uremic toxins.


Asunto(s)
Mastocitos , Estrés Oxidativo , Ácido Úrico , Animales , Ratas , Degranulación de la Célula , Hiperuricemia/metabolismo , Riñón/metabolismo , Riñón/patología , Mastocitos/metabolismo , Renina/metabolismo , Renina/farmacología , Ácido Úrico/metabolismo , Ácido Úrico/farmacología , Valsartán/farmacología , Valsartán/metabolismo
11.
Luminescence ; 37(12): 2018-2027, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36114011

RESUMEN

A new green luminescent phosphor, Li(Y1-x Tbx )GeO4 , was prepared using a high-temperature solid-phase method. The X-ray diffraction (XRD) measured spectrum agreed well with the standard card JCPDS No. 02-3479, indicating that it is a quaternary compound belonging to the space group of Pnma(62) with an orthogonal crystalline phase; the excitation and emission spectra measured using the phosphor spectrometer showed that it can be effectively excited by near-ultraviolet light at 378 nm and blue light at 482 nm, and produced excellent strong emission of green light at 550 nm. The afterglow test results show that the sample had a good long afterglow effect at lower doping concentrations; the thermal stability test results showed that its thermal burst activation energy ΔE ≈ 0.37 eV had its excellent thermal stability. The rare earth Tb3+ -doped green phosphor, LiYGeO4 :Tb3+ , has potential applications in household lighting, medical therapy, and optical storage.


Asunto(s)
Sustancias Luminiscentes , Metales de Tierras Raras , Sustancias Luminiscentes/química , Luminiscencia , Difracción de Rayos X , Litio
12.
Luminescence ; 37(8): 1343-1351, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35689345

RESUMEN

Due to the advantages of good physicochemical properties, thermal stability, and optical properties, double perovskite compounds have received extensive attention. On this basis, a new type of red phosphor, Ca2 YNbO6 :xEu3+ , was synthesized using a high-temperature solid-phase method. Its phase purity, morphology, elemental composition, absorption spectrum, photoluminescence, thermal stability, and Commission Internationale de l'éclairage (CIE) chromaticity coordinates were thoroughly investigated. The results display that there is no impurity phase in the samples and the convergence factor Rwp = 14.2%; the microscopic particles are uniform and full, and the distribution of each element is uniform. The energy band gap ΔE is between 3.71 eV and 3.65 eV. The luminescence intensity is the best when the doped Eu3+ concentration x reaches 0.4, and emits 612 nm red light (5 D0 →7 F2 ) under 465 nm excitation, and the concentration quenching is attributed to a d-d interaction. The luminescence intensity at 425 K was still 75% of the room temperature luminescence intensity, which indicates that the thermal stability is extremely superior. The CIE chromaticity coordinates (0.6534, 0.3455) of the Ca2YNbO6:0.4Eu3+ phosphors are very close to National Television Standards Committee (0.670, 0.330), and the samples have low correlated colour temperature (2656 K) and high colour purity (99.90%). All findings suggest that Ca2 YNbO6 :Eu3+ can serve as a substitute for red phosphor in WLEDs.

13.
Asia Pac J Clin Nutr ; 25(4): 911-919, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27702735

RESUMEN

BACKGROUND AND OBJECTIVES: The aim of this study was to explore the influence of fluoride exposure and ERα gene polymorphisms on reproductive hormone concentrations of women in accordance with endemic fluorosis residence. METHODS AND STUDY DESIGN: A cross sectional study was conducted in Tongxu county, Henan Province, China. A total of 679 women were recruited using cluster sampling and each subject provided fasting blood and an associated urine sample. We measured the concentrations of serum gonadotropin releasing hormone (GnRH), follicle-stimulating hormone, luteinizing hormone, and estradiol and urinary fluoride. RESULTS: In the defluoridation project group (DFPG), serum GnRH was lower in women carrying C/C genotype compared to in those carrying C/T and T/T genotypes of ERα gene rs3798577 (p<0.05). In the endemic fluorosis group (EFG), serum GnRH was lower in women carrying Pp genotype compared to in those carrying PP and pp genotypes of ERα PvuII (p<0.05). Serum GnRH in women from EFG who carried Pp, pp, Xx and xx genotypes in ERα gene PvuII and XbaI was lower than in those in the control group (CG) who carried same genotypes (p<0.05). Furthermore, serum GnRH in women from EFG was significantly lower than in those in CG, regardless of whether the women were carrying C/C, C/T or T/T genotypes of ERα rs3798577 (p<0.05). Serum estradiol concentrations in EFG were significantly lower than in CG when the women were carrying the Pp, Xx and T/T genotypes in ERα gene (p<0.05). CONCLUSION: Interaction of ERα gene and fluoride exposure may influence women's serum reproductive hormone concentrations.


Asunto(s)
Enfermedades Endémicas , Receptor alfa de Estrógeno/genética , Intoxicación por Flúor/epidemiología , Intoxicación por Flúor/genética , Fluoruros/efectos adversos , Hormonas/sangre , Adolescente , Adulto , China/epidemiología , Estudios Transversales , Exposición a Riesgos Ambientales , Estradiol/sangre , Femenino , Fluoruros/orina , Fluorosis Dental , Hormona Folículo Estimulante/sangre , Genotipo , Hormona Liberadora de Gonadotropina/sangre , Humanos , Hormona Luteinizante , Persona de Mediana Edad , Polimorfismo Genético , Adulto Joven
14.
Nanoscale Res Lett ; 11(1): 387, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27599718

RESUMEN

Bilayer magnetoelectric (ME) nanofilms composed of Bi0.9Nd0.1FeO3 (BNF) and Ni0.55Zn0.45Fe2O4 (NZF) were fabricated on the Pt(111)/Ti/SiO2/Si(100) substrates via sol-gel and a subsequent rapid thermal process with different growth sequences of BNF and NZF forming the following layered structures: BNF/NZF and NZF/BNF. The phase composition, microstructure, and ferroelectric, dielectric, ferromagnetic, and ME coupling properties of the composites were investigated at room temperature. Structural characterization by X-ray diffraction and scanning electron microscopy showed that there are no other impurity phases but BNF and NZF, and the nucleation barrier caused that it is easier for NZF and BNF to grow on each other rather than on the surface of Pt/Ti/SiO2/Si. The tests of the physical properties indicated that such heterostructures present both good ferroelectric, ferromagnetic, and dielectric properties and the in-plane ME coupling coefficient α E at room temperature but some discrepancies also exist, which can be attributed to an interfacial effect, in other words, the deposition sequences of the constituent phases have a great influence on the properties of bilayer films.

15.
Ying Yong Sheng Tai Xue Bao ; 21(1): 1-8, 2010 Jan.
Artículo en Chino | MEDLINE | ID: mdl-20387415

RESUMEN

Landsat Thematic Mapper (TM) image was used to estimate Moso bamboo forest biomass, and six atmospheric calibration methods (FLAASH model, 6S model, and DOS1-4 models) were adopted to analysis the effects of atmospheric calibration on the remote sensing estimation of Moso bamboo forest biomass. All the six calibration methods could effectively reduce the atmospheric impacts on TM spectral responses. The relationships between NDVI and Moso bamboo forest biomass under the calibration by the six calibration methods were improved. Great differences were observed in the relationships of Moso bamboo forest biomass with NDVI, II, and MI when using the same calibration methods, suggesting that atmospheric calibration should be made for studying the biophysical significance of vegetation indices. The Landsat TM data corrected with DOS3 model had the highest correlation coefficient with Moso bamboo forest biomass, but there were no significant differences in the correlation coefficients after corrected with the six calibration methods, which indicated that atmospheric calibration might be not required if a single TM image was used for biomass estimation with multiple linear regression model.


Asunto(s)
Atmósfera , Bambusa/crecimiento & desarrollo , Biomasa , Ecosistema , Comunicaciones por Satélite , Calibración , China , Modelos Lineales
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