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1.
Rev Environ Contam Toxicol ; 251: 1-24, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31011831

RESUMO

Heavy metal pollution in surface water is a global environmental problem. This study analyzed the trends, health risks, and sources of eight dissolved heavy metal species in river and lake water across five continents (Africa, Asia, Europe, North America, and South America; Oceania was excluded owing to a lack of data) for the period 1970-2017. We wanted to assess the effects of various implemented countermeasures to pollution and to determine those that could be adopted worldwide. Collectively, the water system showed increasing trends for Cd, Cr, Cu, Ni, Mn, and Fe and decreasing trends for Pb and Zn. The mean dissolved concentrations of most heavy metals were highest in Asia and lowest in Europe. Most heavy metals had low non-carcinogenic risks over this period. The cancer risks associated with Pb were lower than the hazardous level on all five continents over the five decades, whereas the cancer risks related to Cr exceeded the hazardous level in the 1970s, 2000s, and 2010s, and in Africa, Asia, and North America over the entire period. Mining and manufacturing were consistently found to be critical sources of metal pollution from 1970 to 2017. However, the heavy metal sources differed significantly by continent, with waste discharge and rock weathering dominant in Africa; mining and manufacturing, along with rock weathering, are dominant in Asia and South America; fertilizer and pesticide use, along with rock weathering, are dominant in North America; and mining and manufacturing, waste discharge, and rock weathering are dominant in Europe. Global trends in the metal loadings in water and in relevant pollution-control measures suggest that countermeasures in Europe have successfully controlled heavy metal pollution. The successful measures include implementing rigorous standards for metal emissions, limiting the metal concentrations in products, and rigorously treating metal-contaminated waste. Therefore, the measures implemented in Europe should be extended worldwide to treat heavy metal pollution in water.


Assuntos
Exposição Ambiental/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Humanos , Lagos , Rios
2.
Int J Phytoremediation ; 21(3): 240-245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30656962

RESUMO

Bioaccumulation of heavy metals in aquatic plants is significantly affected by hydrological regime and therefore the accumulation and translocation of cadmium in five organs-panicle, leaf, stem, root, and bud-of an emergent plant (Miscanthus sacchariflorus) were compared between the submerged environment and non-submerged environment. In the submerged condition, the cadmium concentration was higher in the panicle and leaf than in the stem, root, and bud. Cadmium concentration in the root exhibited a positive regression with cadmium concentration in the sediment. However, cadmium concentration in the panicle, leaf, stem, and bud exhibited no significant regression with cadmium concentration in the sediment. In the non-submerged environment, the cadmium concentration was higher in the below-ground organs than in the aboveground organs. The mean bioaccumulation coefficient in the 24 investigated plots in the submerged environment was higher than that in the 20 and 40 mg kg-1 cadmium treatments in the non-submerged environment. The mean translocation factor in the submerged environment was nine times higher than that in non-submerged environment. These results indicate that submergence enhanced cadmium bioaccumulation in the aboveground organs and that this plant can be used to remove heavy metals from polluted rivers and lakes.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Cádmio , Poaceae
3.
Nat Commun ; 8(1): 2164, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29255244

RESUMO

Excessive nuclear factor-κB (NF-κB) activation mediated by tumor necrosis factor α (TNFα) plays a critical role in inflammation. Here we demonstrate that angiopoietin-like 8 (ANGPTL8) functions as a negative feedback regulator in TNFα-triggered NF-κB activation intracellularly. Inflammatory stimuli induce ANGPTL8 expression, and knockdown or knockout of ANGPTL8 potentiates TNFα-induced NF-κB activation in vitro. Mechanistically, upon TNFα stimulation, ANGPTL8 facilitates the interaction of IKKγ with p62 via forming a complex, thus promoting the selective autophagic degradation of IKKγ. Furthermore, the N-terminal domain mediated self-oligomerization of ANGPTL8 is essential for IKKγ degradation and NF-κB activation. In vivo, circulating ANGPTL8 level is high in patients diagnosed with infectious diseases, and the ANGPTL8/p62-IKKγ axis is responsive to inflammatory stimuli in the liver of LPS-injected mice. Altogether, our study suggests the ANGPTL8/p62-IKKγ axis as a negative feedback loop that regulates NF-κB activation, and extends the role of selective autophagy in fine-tuned inflammatory responses.


Assuntos
Proteínas Semelhantes a Angiopoietina/metabolismo , Autofagia , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Hormônios Peptídicos/metabolismo , Células A549 , Proteínas Semelhantes a Angiopoietina/sangue , Proteínas Semelhantes a Angiopoietina/genética , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Humanos , Quinase I-kappa B/genética , Inflamação/sangue , Inflamação/genética , Inflamação/metabolismo , Interleucina-1beta/farmacologia , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/genética , Hormônios Peptídicos/sangue , Hormônios Peptídicos/genética , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo
4.
Future Med Chem ; 9(9): 847-858, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28635308

RESUMO

AIM: Sodium-glucose cotransporter 2 (SGLT2) is a promising target for diabetes therapy. We aimed to develop computational approaches to identify structural features for more potential SGLT2 inhibitors. MATERIALS & METHODS: In this work, 46 triazole derivatives as SGLT2 inhibitors were studied using a combination of several approaches, including hologram quantitative structure-activity relationships (HQSAR), topomer comparative molecular field analysis (CoMFA), homology modeling, and molecular docking. HQSAR and topomer CoMFA were used to construct models. Molecular docking was conducted to investigate the interaction of triazole derivatives and homology modeling of SGLT2, as well as to validate the results of the HQSAR and topomer CoMFA models. RESULTS: The most effective HQSAR and topomer CoMFA models exhibited noncross-validated correlation coefficients of 0.928 and 0.891 for the training set, respectively. External predictions were made successfully on a test set and then compared with previously reported models. The graphical results of HQSAR and topomer CoMFA were proven to be consistent with the binding mode of the inhibitors and SGLT2 from molecular docking. CONCLUSION: The models and docking provided important insights into the design of potent inhibitors for SGLT2.


Assuntos
Relação Quantitativa Estrutura-Atividade , Inibidores do Transportador 2 de Sódio-Glicose , Triazóis/farmacologia , Humanos , Modelos Moleculares , Triazóis/síntese química , Triazóis/química
5.
Sci Rep ; 5: 13556, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26324190

RESUMO

Amyloid formation is associated with multiple amyloidosis diseases. Human calcitonin (hCT) is a typical amyloidogenic peptide, its aggregation is associated with medullary carcinoma of the thyroid (MTC), and also limits its clinical application. Magnolia officinalis is a traditional Chinese herbal medicine; its two major polyphenol components, magnolol (Mag) and honokiol (Hon), have displayed multiple functions. Polyphenols like flavonoids and their derivatives have been extensively studied as amyloid inhibitors. However, the anti-amyloidogenic property of a biphenyl backbone containing polyphenols such as Mag and Hon has not been reported. In this study, these two compounds were tested for their effects on hCT aggregation. We found that Mag and Hon both inhibited the amyloid formation of hCT, whereas Mag showed a stronger inhibitory effect; moreover, they both dose-dependently disassembled preformed hCT aggregates. Further immuno-dot blot and dynamic light scattering studies suggested Mag and Hon suppressed the aggregation of hCT both at the oligomerization and the fibrillation stages, while MTT-based and dye-leakage assays demonstrated that Mag and Hon effectively reduced cytotoxicity caused by hCT aggregates. Furthermore, isothermal titration calorimetry indicated Mag and Hon both interact with hCT. Together, our study suggested a potential anti-amyloidogenic property of these two compounds and their structure related derivatives.


Assuntos
Compostos de Bifenilo/metabolismo , Calcitonina/metabolismo , Lignanas/metabolismo , Compostos de Bifenilo/química , Calcitonina/química , Calorimetria , Linhagem Celular Tumoral , Difusão Dinâmica da Luz , Humanos , Lignanas/química , Magnolia/química , Magnolia/metabolismo , Medicina Tradicional Chinesa , Microscopia Eletrônica de Transmissão , Polifenóis/química , Ligação Proteica
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