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1.
Int J Dermatol ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546047

RESUMEN

BACKGROUND: Crisaborole, as a phosphodiesterase 4 (PDE4) inhibitor (PDE4i), effectively inhibits inflammatory pathways, showing promising results in atopic dermatitis (AD), particularly in chronic hyperplasia lesions. OBJECTIVES: Based on real-world data from China, this study assesses the effectiveness and safety of 2% PDE4i ointment as monotherapy for chronic hyperplastic AD lesions. MATERIALS AND METHODS: A total of 49 AD patients aged 12 and above with chronic hyperplastic lesions and Investigator's Static Global Assessment scores of mild or moderate were enrolled. They received 2% PDE4i ointment twice daily until the lesions completely cleared. The effectiveness endpoints comprised the onset time of pruritus and lesion remission and the time of complete lesion clearance. RESULTS: PDE4i demonstrated high effectiveness with minimal irritation, notable improvement in hyperpigmentation, and early remission of pruritus and lesions. The response varied across age groups; elderly patients experienced quicker pruritus relief compared to adolescents and adults, while adolescents showed earlier lesion remission by about 3 days. No significant difference was observed across age groups in the time for complete lesion clearance. Additionally, AD duration (less or more than 3 years) did not significantly impact pruritus or lesion remission. CONCLUSIONS: PDE4i monotherapy is effective and safe for chronic hyperplasia lesions in AD across all age groups, and its effectiveness appears to be independent of AD duration.

2.
J Hazard Mater ; 466: 133624, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38295726

RESUMEN

The generation, migration and reaction paths of electrons are the key steps for photodegradation of pollutants. However, efficient operation of the above pathways is still challenging. Herein, by strong coordination and slow pyrolysis, we constructed a narrow band Zn-Mn bimetallic photoactive core-shell material (Mn@Zn-N-C, Eg = 3.38 eV) with abundant oxygen vacancies for enhancing the above electronic paths. The photodegradation experiments of tetracycline hydrochloride (TCH) showed that the formation and transfer of vacancy-induced free electrons in the synthesized Mn@Zn-N-C was the key to improve the photocatalytic activity. The DFT calculation results revealed that the photogenerated electrons can transfer along the Mn-O-Zn bridge in Mn@Zn-N-C, and promote the formation of MnIV, which directly capture the free electrons and reset itself to MnII site. In this case, the introduction of Mn would enhance the separation of h+ and e-. The adjacent vacancies and defects then also trapped the above free electrons and hinder the recombination of photogenerated carriers. Simultaneously, the localized valence electron transfer between the above redox pairs (Mn4+/Mn2+ and Zn2+/Zn0) also promoted the long-term stability of the photocatalytic process. In summary, using vacancy induction strategy to regulate the evolution of valence- and free-electrons is a promising method to improve the production-transfer-utilization efficiency of photogenerated carriers.

3.
Ecotoxicol Environ Saf ; 268: 115691, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37979359

RESUMEN

The slow rate of electron transfer and the large consumption of carbon sources are technical bottlenecks in the biological treatment of wastewater. Here, we first proposed to domesticate aerobic denitrifying bacteria (ADB) from heterotrophic to autotrophic by electricity (0.6 V) under zero organic carbon source conditions, to accelerate electron transfer and shorten hydraulic retention time (HRT) while increasing the biodegradation rate. Then we investigated the extracellular electron transfer (EET) mechanism mediated by this process, and additionally examined the integrated nitrogen removal efficiency of this system with composite pollution. It was demonstrated that compared with the traditional membrane bioreactor (MBR), the BEC displayed higher nitrogen removal efficiency. Especially at C/N = 0, the BEC exhibited a NO3--N removal rate of 95.42 ± 2.71 % for 4 h, which was about 6.5 times higher than that of the MBR. Under the compound pollution condition, the BEC still maintained high NO3--N and tetracycline removal (94.52 ± 2.01 % and 91.50 ± 0.001 %), greatly superior to the MBR (10.64 ± 2.01 % and 12.00 ± 0.019 %). In addition, in-situ electrochemical tests showed that the nitrate in the BEC could be directly converted to N2 by reduction using electrons from the cathode, which was successfully demonstrated as a terminal electron acceptor.


Asunto(s)
Desnitrificación , Electrones , Carbono , Procesos Heterotróficos , Procesos Autotróficos , Nitratos , Nitrógeno/metabolismo , Reactores Biológicos
4.
Environ Pollut ; 336: 122449, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37633439

RESUMEN

Although alkaline sulfite activation of ferrate (Fe(VI)) has advantages of fast response and high activity for degradation of organic contaminants, the specific production pathways of active species and the pH conditions still hinder its widespread application. Based on this, our study constructed a novel advanced oxidation process of calcium sulfite (CaSO3) could activated Fe(VI) continuously by Ca2+ buffering and investigated the mechanism under different pH values and CaSO3 dosages with ciprofloxacin as a target organic pollutant. The results showed that Ca2+ stabilized the process at a neutral/weakly alkaline microenvironment of pH 7-8, which could alleviate the hydrolysis of ≡FeIV=O by protons and iron hydroxyl groups. Besides, the removal of pollutants occurred efficiently when sulfate (SO32-) was excessive and had a 3:1 ratio of SO32- to Fe(VI), achieving more than 99% removal of electron-rich phenolic organic pollutants within 2 min. By adding different radical scavengers and combining electrochemical analysis methods and electron paramagnetic resonance spectroscopy techniques to revealed that the main active species in Fe(VI)/CaSO3 process were ≡FeIV=O/≡FeV=O. Furthermore, the reactivity of various sulfate species (such as SO32-, SO3•-, SO4•-, SO5•-) with Fe(VI) was calculated using density functional theory (DFT), and it was found that Fe(VI)-SO32- reaction has a much lower energy barrier (-36.08 kcal/mol), indicating that SO32- can readily activate Fe(VI) and generate ≡FeIV=O to attack the atoms with high Fukui index (f -) in organic pollutants. The above results confirm the feasibility of Fe(VI)/CaSO3 process. Thus, this study can theoretically and practically prove that the main active species is ≡FeIV=O, rather than SO4•- or •OH in Fe(VI)/CaSO3 process.


Asunto(s)
Calcio , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Hierro/química , Oxidación-Reducción , Sulfitos , Óxidos de Azufre , Sulfatos
5.
J Environ Manage ; 323: 116256, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36126592

RESUMEN

Defects and vacancies are the essential reasons for the removal of heavy metal ions from wastewater by low-cost biochar materials. This study aimed to use chemically activated hemp stem core alkali extraction residue biochar as an adsorbent to remove nickel (Ni) and copper (Cu) ions from the simulated waste liquid. A large number of defects and vacancies were introduced into the pyrolysis process to study the efficient removal of heavy metal ions Cu and Ni by hemp rod biomass carbon material (HSR-BC) with different carbon base mass ratios and temperatures. The specific surface area of the prepared hemp rod active biochar was highly correlated with the aperture and carbon base ratio and temperature, and reached the maximum value (1429 m2/g) at 600 °C with the ratio of carbon to base (1:3.5). The removal rates of heavy metals Ni(II) and Cu(II) were as high as 94.25% and 99.54%, respectively, and the adsorption capacities were up to 7.85 mg/g and 24.88 mg/g. The adsorption isotherm follows the Langmuir equation and chemo-adsorption was the main adsorption process. Comparing the surface defects and vacancies of biochar materials before and after adsorption showed that the defects of sp-C and oxygen vacancies produced on the edge of the carbon were the main active sites of the biochar material, an amount of carbon defects would become an anchor site for the Lewis acidic groups, the defective acid site strengthened the electron transfer between the functional group and the Ni(II)/Cu(II), promoted the strong cooperation of Ni(II)/Cu(II) ions with -COOH group to enable efficient and rapid adsorption removal. In addition, a large number of carbon-deficient structures could quickly anchor the Ni(II)/Cu(II) due to their local electron deficiency state, which was difficult to desorb. This study provided an in-depth understanding and guidance for the development of low-cost biochar materials with excellent removal performance of heavy metal ions.


Asunto(s)
Cannabis , Metales Pesados , Contaminantes Químicos del Agua , Adsorción , Álcalis , Carbono , Carbón Orgánico , Cobre , Iones , Cinética , Metales Pesados/química , Níquel , Oxígeno , Aguas Residuales , Contaminantes Químicos del Agua/química
7.
Eur J Pharmacol ; 734: 1-8, 2014 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-24685639

RESUMEN

Exposure to ultraviolet (UV) radiation leads to a progressive increase in dermal damage through the degradation of collagen, which is mediated by matrix metalloproteinases (MMPs). UV radiation alters the intracellular signaling events that regulate the elaboration of MMPs. Our previous study showed that P165, the N-terminal 5-mer peptide analog of amyloid precursor protein, exerts a protective effect on ultraviolet A (UVA)-induced loss of collagen type I in human dermal fibroblasts (HDFs) by inhibiting the generation of intracellular reactive oxygen species and MMP-1. In this study, we focused on specific signal transduction pathways to elucidate the possible photoprotective mechanisms of P165 in controlling MMP-1 inhibition. Results from western blot analyses indicated that pretreatment with P165 dose-dependently inhibited UVA-induced phosphorylation of extracellular regulated protein kinases (ERK), c-Jun N-terminal kniase (JNK), p38 mitogen-activated protein kinases (MAPKs), and the phosphorylation of their downstream targets c-Jun and c-Fos. The photoprotective effects of P165 were further demonstrated in collagen type I secretion and cellular senescence induced by UVA irradiation. These findings suggest that P165 exerts photoprotective activity in UVA-treated HDFs by regulating MMP-1 generation. This activity may be mediated by inhibiting the MAPK signaling pathways. Thus, P165 is a potential agent for the prevention of skin photoaging.


Asunto(s)
Precursor de Proteína beta-Amiloide/química , Fibroblastos/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasa 1 de la Matriz/metabolismo , Oligopéptidos/farmacología , Rayos Ultravioleta/efectos adversos , Colágeno Tipo I/metabolismo , Activación Enzimática/efectos de los fármacos , Activación Enzimática/efectos de la radiación , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/efectos de la radiación , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de la radiación , Fosforilación/efectos de los fármacos , Fosforilación/efectos de la radiación , Proteínas Proto-Oncogénicas c-fos/metabolismo , Piel/citología , beta-Galactosidasa/metabolismo
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