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1.
Front Biosci (Landmark Ed) ; 29(1): 22, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38287830

RESUMO

Understanding the pathogenesis of different phenotypes of asthma, including glucocorticoid-dependent and glucocorticoid-resistant asthma, is crucial for the development of effective treatments. Autophagy, a fundamental cellular process involved in cell homeostasis, has been implicated in asthma, although the exact mechanisms remain unclear. Recent studies have identified autophagy activation in eosinophilic, neutrophilic, and paucigranulocytic asthma, providing novel insights into the disease. This comprehensive review examines the role of autophagy in the pathogenesis and treatment of asthma, with a focus on various cell types. The goal is to uncover potential therapeutic targets and innovative treatment modalities to improve patient outcomes in clinical settings.


Assuntos
Asma , Neutrófilos , Humanos , Neutrófilos/metabolismo , Glucocorticoides/uso terapêutico , Asma/tratamento farmacológico , Asma/metabolismo , Autofagia , Fenótipo , Inflamação/metabolismo
2.
Dalton Trans ; 52(46): 17438-17448, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37947491

RESUMO

An NiMo alloy bonded with sulfur (NiMoS) exhibits enhanced surface affinity toward water and organic molecules, thereby enhancing electrocatalytic hydrogenation (ECH) reactions through synergistic effects. In industrial processes, indigo, an ancient dye employed in the denim industry, is typically chemically reduced using sodium dithionite. However, this process generates an excess of toxic sulfide, which heavily contaminates the environment. ECH is a sustainable alternative for indigo reduction due to its reduced reliance on chemicals and energy consumption. In this study, carbon-felt (CF)-supported NiMoS was synthesized in a two-step process. First, the NiMo alloy was electrodeposited onto the CF surface, followed by sulfidation in an oven at 600 °C. NiMoS exhibits a larger electrochemically active surface area and a smaller charge transfer resistance compared to pure Ni and NiMo. Furthermore, NiMoS demonstrates excellent thermodynamic and kinetic properties for water splitting in strong alkaline solutions (1.0 M KOH). Additionally, optimal reaction conditions for the ECH of indigo were explored. Under the conditions of a 1.0 M KOH hydroxide medium with 10% methanol (v/v), an indigo concentration of 5 g L-1, a reaction temperature of 70 °C, and a current density of 10 mA cm-2, NiMoS/CF achieved remarkable improvements in both conversion (99.2%) and Faraday efficiency (38.1%). The results of this experimental work offer valuable insights into the design and application of novel catalytic materials for the ECH of vat dyes, opening up new possibilities for sustainable and environmentally friendly processes in the dye industry.

3.
Environ Sci Pollut Res Int ; 30(31): 77127-77138, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37253910

RESUMO

Copper (Cu) can be harmful to host physiology at high levels, although it is still unclear exactly how it causes nephrotoxicity. Mitochondrial dysfunction and endoplasmic reticulum (ER) stress are associated with heavy metal intoxication. Meanwhile, mitochondria and ER are connected via mitochondria-associated ER membranes (MAM). In order to reveal the crosstalk between them, a total of 144 1-day-old Peking ducks were randomly divided into four groups: control (basal diet), 100 mg/kg Cu, 200 mg/kg Cu, and 400 mg/kg Cu groups. Results found that excessive Cu disrupted MAM integrity, reduced the co-localization of IP3R and VDAC1, and significantly changed the MAM-related factors levels (Grp75, Mfn2, IP3R, MCU, PACS2, and VDAC1), leading to MAM dysfunction. We further found that Cu exposure induced mitochondrial dysfunction via decreasing the ATP level and the expression levels of COX4, TOM20, SIRT1, and OPA1 and up-regulating Parkin expression level. Meanwhile, Cu exposure dramatically increased the expression levels of Grp78, CRT, and ATF4, resulting in ER stress. Overall, these findings demonstrated MAM plays the critical role in Cu-induced kidney mitochondrial dysfunction and ER stress, which deepened our understanding of Cu-induced nephrotoxicity.


Assuntos
Cobre , Patos , Animais , Cobre/toxicidade , Cobre/metabolismo , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Rim/metabolismo , Estresse do Retículo Endoplasmático
4.
Chem Biol Interact ; 362: 109981, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35588787

RESUMO

Vanadium (V) is a common environmental and industrial pollutant that can cause nephrotoxicity in animals in excess. The purpose of this research was to explore the interaction between endoplasmic reticulum (ER) stress and autophagy induced by V in the kidney of ducks. Duck renal tubule epithelial cells were exposed to different concentrations of sodium metavanadate (NaVO3) (0, 100 and 200 µM) and PERK inhibitor (GSK, 1 µM), or autophagy inhibitor (chloroquine, 50 µM) alone for 24 h (chloroquine for the last 4 h). The results showed that exposure to V caused the dilatation and swelling of the ER and intracellular calcium overload, and upregulated PERK, eIF2α, ATF4 and CHOP mRNA levels and p-PERK and CHOP protein levels associated with ER stress in cells. Additionally, V markedly increased the number of autophagosomes, acidic vesicular organelles (AVOs) and LC3 puncta, as well as the mRNA levels of Beclin1, Atg5, Atg12, LC3A and LC3B and protein levels of Beclin1, Atg5 and LC3B-II/LC3B-I, but decreased the imRNA and protein levels of p62. Moreover, treatment with the PERK inhibitor ameliorated the changed factors above induced by V, but the V-induced variation of ER-stress related factors were aggravated after treatment with the autophagy inhibitor. Together, our data suggested that excessive V could induce ER stress and autophagy in duck renal tubular epithelial cells. ER stress might promote V-induced autophagy via the PERK/ATF4/CHOP signaling pathway, and autophagy may play a role in alleviating ER stress induced by V.


Assuntos
Patos , Estresse do Retículo Endoplasmático , Animais , Apoptose , Autofagia , Proteína Beclina-1 , Cloroquina/toxicidade , Patos/genética , Patos/metabolismo , Células Epiteliais/metabolismo , RNA Mensageiro , Vanádio , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
5.
J Inorg Biochem ; 232: 111809, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35421768

RESUMO

Vanadium (V) is necessary for the health and growth of animals, but excessive V has harmful effects on the ecosystem health. Endoplasmic reticulum (ER)-mitochondria coupling as a membrane structure connects the mitochondrial outer membrane with the ER. The mitochondria-associated ER membrane (MAM) is a region of the ER-mitochondria coupling and is essential for normal cell function. Currently, the crosstalk between ER-mitochondrial coupling and apoptosis in the toxic mechanism of V on duck kidney is still unclear. In this study, duck renal tubular epithelial cells were incubated with different concentrations of sodium metavanadate (NaVO3) and/or inositol triphosphate receptor (IP3R) inhibitor 2-aminoethyl diphenyl borate (2-APB) for 24 h. The results showed that V could significantly increase lactate dehydrogenase (LDH) release, the mitochondrial calcium level and the numbers of the fluorescent signal points of IP3R; shortened the length ER-mitochondria coupling and reduced its formation; markedly upregulate the mRNA levels of MAM-related genes and protein levels, causing MAM dysfunction. Additionally, V treatment appeared to upregulate pro-apoptotic genes and downregulate anti-apoptotic genes, followed by cell apoptosis. The V-induced changes were alleviated by treatment with IP3R inhibitor. In summary, V could induce the dysfunction of ER-mitochondrial coupling and apoptosis, and inhibition of ER-mitochondrial coupling could attenuate V-induced apoptosis in duck renal tubular epithelial cells.


Assuntos
Patos , Vanádio , Animais , Apoptose , Cálcio/metabolismo , Patos/metabolismo , Ecossistema , Retículo Endoplasmático , Células Epiteliais/metabolismo , Mitocôndrias , Vanádio/farmacologia
6.
Phys Chem Chem Phys ; 19(24): 16281, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28607982

RESUMO

Correction for 'Preparation of Mo nanopowders through electroreduction of solid MoS2 in molten KCl-NaCl' by Haiping Gao et al., Phys. Chem. Chem. Phys., 2014, 16, 19514-19521.

7.
Angew Chem Int Ed Engl ; 56(7): 1751-1755, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28090748

RESUMO

Although, in the carbon family, graphite is the most thermodynamically stable allotrope, conversion of other carbon allotropes, even amorphous carbons, into graphite is extremely hard. We report a simple electrochemical route for the graphitization of amorphous carbons through cathodic polarization in molten CaCl2 at temperatures of about 1100 K, which generates porous graphite comprising petaloid nanoflakes. This nanostructured graphite allows fast and reversible intercalation/deintercalation of anions, promising a superior cathode material for batteries. In a Pyr14 TFSI ionic liquid, it exhibits a specific discharge capacity of 65 and 116 mAh g-1 at a rate of 1800 mA g-1 when charged to 5.0 and 5.25 V vs. Li/Li+ , respectively. The capacity remains fairly stable during cycling and decreases by only about 8 % when the charge/discharge rate is increased to 10000 mA g-1 during cycling between 2.25 and 5.0 V.

8.
Phys Chem Chem Phys ; 16(36): 19514-21, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-25105181

RESUMO

Electrolysis of MoS2 to produce Mo nanopowders and elemental sulfur has been studied in an equimolar mixture of NaCl and KCl at 700 °C. The reduction mechanism was investigated by cyclic voltammetry (CV), potentiostatic and constant voltage electrolysis together with spectroscopic and scanning electron microscopic analyses. The reduction pathway was identified to be MoS2 → LxMoS2 (x ≤ 1, L = Na or K) → L3Mo6S8 and LMo3S3 → Mo, and the last step to format metallic Mo was found to be relatively slow in kinetics. Electrolysis at a cell voltage of 2.7 V has led to a rapid reduction of MoS2 to nodular Mo nanoparticles (50-100 nm), with the current efficiency and energy consumption being about 92% and 2.07 kW h kg(-1)-Mo, respectively.

9.
Chemistry ; 16(20): 5920-6, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20397159

RESUMO

Heterodimer nanostructures have attracted extensive attention, owing to an increasing degree of complexity, functionality, and then importance. So far, all the reported ones are built from solid nanoparticles. Herein, nearly monodisperse heterodimer nanostructures are constructed by hollow PbS(x) and solid Au domains simultaneously through a mild reaction between PbS nanocrystals and the gold species in the presence of dodecylamine. Control experiments clearly reveal the underlying formation mechanism of the hollow PbS(x)-solid Au heterodimers. The Au(III) species in the solution, lead to the etching of PbS nanocrystals and the Au(I) species facilitate the control of the number of gold domains per nanoparticle. Dodecylamine molecules not only work as a stabilizer in the reaction, but also act as a reducing agent that could greatly affect the morphology of the product. The optical properties of the heterodimers are investigated based on UV/Vis absorption spectroscopy and Raman spectroscopy. This novel heterodimer nanostructure pushes the development of complex nanocrystal-based architectures forward, and also provides many opportunities for potential applications.

10.
Recent Pat Nanotechnol ; 3(3): 192-202, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19958284

RESUMO

Quantum dot-encoded beads as a new type of fluorescent labels exhibit significant advantages over common organic dyes, such as narrow, strong and tunable emissions, excellent photo stability, good versatility in structure and component, and simplicity for excitation of multiple nanocrystals. These features lead to the great potential of the beads in the fields of ultrasensitive detections, clinical diagnostics, as well as molecular imaging. This report will briefly review the fabrication and optical properties of the beads based on recent papers and patents. The applications of the beads in ultrasensitive detections are also discussed. The systematic introduction from basic studies to practical applications would give us a comprehensive and clear view about this field, disclose the current challenges, and promote their future developments.


Assuntos
Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Patentes como Assunto , Pontos Quânticos , Transdutores , Estados Unidos
11.
Angew Chem Int Ed Engl ; 48(22): 3991-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19378313

RESUMO

Turing lead into gold: Hollow hybrid PbS(x)-Au nanostructures of about 10 nm in diameter were synthesized using a one-step reaction under mild experimental conditions. The redox reaction of gold precursors with PbS nanocrystals in the presence of dodecylamine leads to the hollow feature of hybrid nanostructures (see picture).

12.
Nanotechnology ; 19(25): 255603, 2008 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-21828655

RESUMO

This paper describes the development of a novel and simple chemical route to mass production of mesoporous ZnS nanoparticles in high yield. XRD, FESEM, TEM, SAED, EDS and XPS analyses show that spherical nanoparticles are crystalline ZnS in a zinc-blende structure. The resulting nanoparticles have an average diameter of about 30 nm and pore sizes in the range of 3-6 nm. The formation of mesoporous nanostructures could be attributed to higher nucleation rate in the course of preparation that resulted in the quick aggregation of initial crystallites and the formation of pores between them. The as-prepared mesoporous ZnS exhibited excellent photocatalytic activities. This preparation method provides one possible route to the synthesis of other mesoporous structures for exploratory studies on the applications of mesoporous nanocrystals.

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