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1.
Sci Total Environ ; 935: 173303, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38761948

RESUMO

Cadmium (Cd) and sulfamethoxazole (SMX) frequently coexist in farmlands, yet their synergistic toxicological impacts on terrestrial invertebrates remain unexplored. In this study, earthworms were exposed to artificial soils percolated with Cd (5 mg/kg), SMX (5 mg/kg) or combination of them for 7 days, followed by a 12-day elimination phase in uncontaminated soil. The uptake of Cd and SMX by the earthworms, along with their subcellular distribution, was meticulously analyzed. Additionally, a suite of biomarkers-including superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and weight loss-were evaluated to assess the health status of the earthworms and the toxicological effects of the Cd and SMX mixture. Notably, the cotreatment with Cd and SMX resulted in a significantly higher weight loss in Eisenia fetida (41.25 %) compared to exposure to Cd alone (26.84 %). Moreover, the cotreatment group exhibited substantially higher concentrations of Cd in the total internal body, fraction C (cytosol), and fraction E (tissue fragments and cell membranes) in Eisenia fetida compared to Cd alone counterparts. The combined exposure also significantly elevated the SMX levels in the total body and fraction C compared with the SMX-only treated earthworms. Additionally, Eisenia fetida subjected to the combined treatment showed markedly increased activities of SOD, CAT, and MDA compared to those treated with Cd alone. The effect addition indices (EAIs), ranging from 1.00 to 2.23, unequivocally demonstrated a synergistic effect of the combined treatments. Interestingly, relocating the earthworms to clean soil did not mitigate the observed adverse effects. These findings underscore the increased risk posed by the Cd-SMX complex to terrestrial invertebrates in agricultural areas.


Assuntos
Biomarcadores , Cádmio , Oligoquetos , Poluentes do Solo , Sulfametoxazol , Oligoquetos/efeitos dos fármacos , Oligoquetos/fisiologia , Animais , Sulfametoxazol/toxicidade , Cádmio/toxicidade , Poluentes do Solo/toxicidade , Biomarcadores/metabolismo , Malondialdeído/metabolismo , Superóxido Dismutase/metabolismo , Catalase/metabolismo
2.
Phys Chem Chem Phys ; 23(20): 11764-11773, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33982714

RESUMO

Ni based catalysts have been widely studied for H2 production due to the ability of Ni to break C-C and C-H bonds. In this work, we study inverse catalysts prepared by well-controlled sub-monolayer deposition of CeO2 nanocubes onto Ni thin films for ethanol steam reforming (ESR). Results show that controlling the coverage of CeO2 nanocubes on Ni enhances H2 production by more than an order of magnitude compared to pure Ni. Contrary to the idea that C deposits must be continuously oxidized for sustained H2 production, the surface of the most active catalysts show significant C deposition, yet no deactivation is observed. HAADF-STEM analysis reveals the formation of carbon filaments (CFILs), which propel Ni particles upward at the filament tips via a catalytic tip growth mechanism, resulting in a Ni@CFIL active phase for ESR. Near-ambient pressure XPS indicates that the Ni@CFIL active phase forms as a result of C gradients at the interface between regions of pure Ni metal and domains of closely packed CeO2 nanocubes. These results show that the mesoscale morphology of deposited CeO2 nanocubes is responsible for templating the formation of a Ni@CFIL catalyst, which resists deactivation leading to highly active and stable H2 production from ethanol.

3.
Br J Ophthalmol ; 104(9): 1277-1282, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31744795

RESUMO

AIMS: To construct a program to predict the visual acuity (VA), best corrected VA (BCVA) and spherical equivalent (SE) of patients with retinopathy of prematurity (ROP) from 3 to 12 years old after intravitreal injection (IVI) of anti-vascular endothelial growth factor and/or laser photocoagulation treatment. METHODS: This retrospective study employed a feedforward artificial neural network with an error backpropagation learning algorithm to predict visual outcomes based on patient birth data, treatment received and age at follow-up. Patients were divided into two groups based on prior treatments. The main outcome measures were the difference between the predicted and actual values of visual outcomes. These were analysed using the normalised root mean square error (RMSE). Two-way repeated measures analysis of variance was used to compare the predictive accuracy by this algorithm. RESULTS: A total of 60 ROP infants with prior treatments were included. In the IVI group, the normalised average RMSE for VA, BCVA, and SE was 0.272, 0.185 and 0.131, respectively. In the laser group, the normalised average RMSE for VA, BCVA and SE was 0.190, 0.250 and 0.104, respectively. This result shows that better predictive power was obtained for SE than for VA or BCVA in both the IVI and laser groups (p<0.001). In addition, the algorithm performed slightly better in predicting visual outcomes in the laser group (p<0.001). CONCLUSIONS: This algorithm offers acceptable power for predicting visual outcomes in patients with ROP with prior treatment. Predictions of SE were more precise than predictions of for VA and BCVA in both groups.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Fotocoagulação a Laser , Redes Neurais de Computação , Retinopatia da Prematuridade/fisiopatologia , Retinopatia da Prematuridade/terapia , Acuidade Visual/fisiologia , Bevacizumab/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Injeções Intravítreas , Masculino , Valor Preditivo dos Testes , Ranibizumab/uso terapêutico , Refração Ocular/fisiologia , Retinopatia da Prematuridade/tratamento farmacológico , Retinopatia da Prematuridade/cirurgia , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
4.
Med Hypotheses ; 85(2): 207-11, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25957655

RESUMO

Osteoarthritis of the knee affects a large population worldwide and is associated with an extremely high economic burden largely attributable to the effects of disability, comorbid disease, and the expense of treatment. Since the initiating events that result in the cartilage degradation are poorly understood, there has been very limited success in demonstrating disease modification in clinical trials of potential therapies. Medial plica related medial abrasion phenomenon has recently been identified to have close relationship with medial compartment osteoarthritis. We hypothesized that this abrasion phenomenon will elicit lifelong interplay between pathologic medial plica and the facing medial femoral condyle and might play a role in the pathogenesis of knee osteoarthritis by both physical and chemical effects. After evaluating current evidence, we designed a study to prove that the concentrations of total protein, cartilage degrading related cytokines (tumor necrosis factor-α and interleukin-1ß) and enzyme (matrix metalloproteinase-3) are higher in the medial compartment of the knee having the phenomenon of medial abrasion. The accumulating data and findings about medial abrasion phenomenon might be important for the understanding of the pathogenesis or progression of this common disease. We hope that our hypothesis will stimulate further studies verifying if medial abrasion phenomenon plays more roles in the pathogenesis of knee osteoarthritis. Further clinical observations for its appropriate treatment based on this hypothesis are also mandatory for the benefits of patients.


Assuntos
Modelos Biológicos , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/fisiopatologia , Membrana Sinovial/fisiopatologia , Sinovite/complicações , Sinovite/fisiopatologia , Simulação por Computador , Citocinas/imunologia , Humanos , Meniscos Tibiais/fisiopatologia
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