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1.
J Fluoresc ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695976

RESUMO

Carbon quantum dots (CQDs) were greenly synthesized via a single-step hydrothermal method, using the trunks of Bauhinia purpurea as the carbon source. They exhibited good dispersibility, water solubility, high sensitivity, and great stability with a spherical form and a particle size of 2.68 ± 0.32 nm. By utilizing the inner filter effect and dynamic quenching effect, the fluorescence quenching of CQDs can be induced to detect quinoline yellow. Detailed experimental results showed that the change rate of fluorescence intensity of CQDs had a good linear relationship with varying concentrations of quinoline yellow (2-128 µmol/L). It can be clearly observed that the fluorescence quenching occurred within 1 min, its correlation coefficient (R2) is 0.9912, and the detection limit (DL) is 1.7884 µmol/L, substantially lower than the maximum concentration stipulated by the national standard of 209.5 µmol/L. Furthermore, quinoline yellow had been successfully detected in real beverage samples using CQDs, with the recovery rates of 90.6%-110.4% and the relative standard deviation (RSD) ≤ 6.3% and it also showed great anti-interference and selectivity. These findings indicate that the detected quinoline yellow of CQDs possess substantial promise for a wide range of applications within the detected artificial food colors field.

2.
Ecotoxicol Environ Saf ; 272: 116050, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38325272

RESUMO

Silica nanoparticles (SiNPs) are widely used in the biomedical field and can enter the central nervous system through the blood-brain barrier, causing damage to hippocampal neurons. However, the specific mechanism remains unclear. In this experiment, HT22 cells were selected as the experimental model in vitro, and the survival rate of cells under the action of SiNPs was detected by MTT method, reactive oxygen species (ROS), lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and adenosine triphosphate (ATP) were tested by the kit, the ultrastructure of the cells was observed by transmission electron microscope, membrane potential (MMP), calcium ion (Ca2+) and apoptosis rate were measured by flow cytometry, and the expressions of mitochondrial functional protein, mitochondrial dynein, mitochondrial autophagy protein as well as apoptosis related protein were detected by Western blot. The results showed that cell survival rate, SOD, CAT, GSH-Px, ATP and MMP gradually decreased with the increase of SiNPs concentration, while intracellular ROS, Ca2+, LDH and apoptosis rate increased with the increase of SiNPs concentration. In total cellular proteins,the expressions of mitochondrial functional proteins VDAC and UCP2 gradually increased, the expression of mitochondrial dynamic related protein DRP1 increased while the expressions of OPA1 and Mfn2 decreased. The expressions of mitophagy related proteins PINK1, Parkin and LC3Ⅱ/LC3Ⅰ increased and P62 gradually decreased, as well as the expressions of apoptosis related proteins Apaf-1, Cleaved-Caspase-3, Caspase-3, Caspase-9, Bax and Cyt-C. In mitochondrial proteins, the expressions of mitochondrial dynamic related proteins DRP1 and p-DRP1 were increased, while the expressions of OPA1 and Mfn2 were decreased. Expressions of mitochondrial autophagy associated proteins PINK1, Parkin, LC3II/LC3I increased, P62 decreased gradually, as well as the expressions of apoptosis related proteins Cleaved-Caspase-3, Caspase-3, and Caspase-9 increased, and Cyt-C expressions decreased. To further demonstrate the role of ROS and DRP1 in HT22 cell apoptosis induced by SiNPs, we selected the ROS inhibitor N-Acetylcysteine (NAC) and Dynamin-related protein 1 (DRP1) inhibitor Mdivi-1. The experimental results indicated that the above effects were remarkably improved after the use of inhibitors, further confirming that SiNPs induce the production of ROS in cells, activate DRP1, cause excessive mitochondrial division, induce mitophagy, destroy mitochondrial function and eventually lead to apoptosis.


Assuntos
Dinaminas , Mitofagia , Nanopartículas , Dióxido de Silício , Trifosfato de Adenosina , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Dinaminas/metabolismo , Nanopartículas/toxicidade , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/farmacologia , Superóxido Dismutase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Camundongos , Linhagem Celular Tumoral
3.
Environ Toxicol ; 38(2): 289-299, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36416502

RESUMO

There is no ideal therapy for testicular damage induced by Cr(VI); however, bone marrow mesenchymal stem cells (BMSCs) transplantation may be a promising therapy. A Cr(VI) solution was administered to rats by intraperitoneal injection for 30 days, then BMSCs from donor rats were transplanted. Two weeks later, decreased activity and appetite, along with other pathological changes, were improved in the BMSCs group. The location of BMSCs in damaged testes was observed via laser confocal microscopy. Chromium content in the Cr(VI) and BMSCs groups significantly increased compared with that in the control group, but there was no significant difference between the two groups, as revealed by atomic absorption spectrometry. The ferrous iron and the total iron content of testes in the BMSCs group were significantly lower than those in the Cr(VI) group, as observed by Lillie staining and a tissue iron assay kit. Western blotting and immunohistochemical analyses revealed that the expression of Beclin 1, LC3B, 4-hydroxynonenal, and transferrin receptor 1 was decreased in the BMSCs group, compared with the Cr(VI) group. The expression of glutathione peroxidase 4 (GPX4), SLC7A11, p-AKT, mammalian target of rapamycin (mTOR), and p-mTOR in the BMSCs group was higher than that in the Cr(VI) group. Taken together, we propose that BMSCs repair Cr(VI)-damaged testes by alleviating ferroptosis and downregulating autophagy-associated proteins through the upregulation of AKT and mTOR phosphorylation.


Assuntos
Células da Medula Óssea , Ferroptose , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Testículo , Animais , Ratos , Autofagia , Células da Medula Óssea/metabolismo , Cromo/toxicidade , Ferro/metabolismo , Células-Tronco Mesenquimais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Testículo/efeitos dos fármacos , Testículo/lesões , Testículo/cirurgia
4.
Nanotechnology ; 33(34)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902851

RESUMO

Chemisorbed oxygen acts a crucial role in the redox reaction of semiconductor gas sensors, and which is of great significance for improving gas sensing performance. In this study, an oxygen-plasma-assisted technology is presented to enhance the chemisorbed oxygen for improving the formaldehyde sensing performance of SnO2electropun fiber. An inductively coupled plasma device was used for oxygen plasma treatment of SnO2electrospun fibers. The surface of SnO2electrospun fibers was bombarded with high-energy oxygen plasma for facilitating the chemisorption of electronegative oxygen molecules on the SnO2(110) surface to obtain an oxygen-rich structure. Oxygen-plasma-assisted SnO2electrospun fibers exhibited excellent formaldehyde sensing performance. The formaldehyde adsorption mechanism of oxygen-rich SnO2was investigated using density functional theory. After oxygen plasma modification, the adsorption energy and the charge transfer number of formaldehyde to SnO2were increased significantly. And an unoccupied electronic state appeared in the SnO2band structure, which could enhance the formaldehyde adsorption ability of SnO2. The gas sensing test revealed that plasma-treated SnO2electrospun fibers exhibited excellent gas sensing properties to formaldehyde, low operating temperature, high response sensitivity, and considerable cross-selectivity. Thus, plasma modification is a simple and effective method to improve the gas sensing performance of sensors.

5.
Environ Toxicol ; 37(8): 1891-1901, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35396826

RESUMO

Methylmercury (MeHg) is an environmental neurotoxic substance, which can easily cross the blood-brain barrier, causing irreversible damage to the human central nervous system. Reactive oxygen species (ROS) are involved in various ways of intracellular physiological or pathological processes including neuronal apoptosis. This study attempted to explore the role of ROS-mediated poly ADP-ribose polymerase (PARP)/apoptosis-inducing factor (AIF) apoptosis signaling pathway in the process of MeHg-induced cell death of human neuroblastoma cells (SH-SY5Y). Here, we found that SH-SY5Y cells underwent apoptosis in response to MeHg, which was accompanied by the increased levels of ROS and calcium ion, and the activation of caspase cascades and PARP. Inhibiting the production of ROS can reduce the apoptosis rate to a certain extent. PARP/AIF apoptotic pathway is independent of caspase dependent signaling pathway and regulates it. In conclusion, these results suggest that ROS mediated activation of caspase pathway and PARP/AIF signaling pathway are involved in MeHg induced apoptosis, and these two pathways interact with each other.


Assuntos
Compostos de Metilmercúrio , Neuroblastoma , Adenosina Difosfato Ribose/farmacologia , Apoptose , Fator de Indução de Apoptose/metabolismo , Fator de Indução de Apoptose/farmacologia , Caspases/metabolismo , Humanos , Compostos de Metilmercúrio/toxicidade , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Clin Lab ; 67(10)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655193

RESUMO

BACKGROUND: As a serious public universal health issue, metabolic syndrome (MetS) has a high prevalence world-wide. Some studies illustrated that GCKR modulated insulin action and serum lipids are critical diagnostic criteria of MetS. The goal of this study is to investigate the association between GCKR polymorphisms with metabolic syndrome (MetS) in a Han population from northeast China. METHODS: Four single nucleotide polymorphisms (SNPs, rs1260326, rs8179206, rs780094, and rs2293571) were genotyped in 3,754 participants. MetS was defined according to International Diabetes Federation criteria (2009). Genotype and allele frequency distributions were compared between two groups by chi-squared test. The associations of the four SNPs under different genetic models with MetS were tested by multivariate logistic regression analysis adjusted for age, gender, location, education, occupation alcohol consumption, and smoking. p-values of no more than 0.003125 [0.05/(4 SNPs*4 different genetic models)] after Bonferroni correction were considered statistically significant. Linkage disequilibrium (LD) and haplotype analysis were evaluated by the Haploview software (version 4.2) and SNPStats program. RESULTS: Logistic regression analysis revealed that after Bonferroni correction, rs780094 was associated with MetS under the recessive model (p = 0.002). Weak LD was found for the four SNPs, and the CAGC haplotype appeared to be significantly decreased the risk of MetS (p = 0.026, OR = 0.88, 95% CI = 0.79 - 0.98). CONCLUSIONS: GCKR rs780094 was associated with MetS in northeast Han population, and haplotype CAGC generated by rs1260326, rs8179206, rs780094, and rs2293571 may decrease the risk of the disease.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Síndrome Metabólica , Proteínas Adaptadoras de Transdução de Sinal/genética , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Frequência do Gene , Predisposição Genética para Doença , Haplótipos , Humanos , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/genética , Polimorfismo de Nucleotídeo Único
7.
Chem Biodivers ; 18(5): e2100106, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33759356

RESUMO

In search of new environmentally friendly and effective antifungal agents, a series of 4-aminoquinolines bearing a 1,3-benzodioxole moiety were prepared and their structures were fully elucidated by spectroscopic analyses. The antifungal activities of all the target compounds against five phytopathogenic fungi were evaluated in vitro. The results revealed that most of the newly synthesized compounds exhibited obvious inhibitory activities at the concentration of 50 µg/mL. Among them, 6-(furan-2-yl)-N-(4-methylphenyl)-2H-[1,3]dioxolo[4,5-g]quinolin-8-amine hydrochloride (7m) displayed more promising antifungal potency with EC50 values of 10.3 and 14.0 µg/mL against C. lunata and A. alternate, respectively. Particularly, the EC50 value of 7m against C. lunata was 7.3-fold as potent as the standard azoxystrobin. There were some significant morphological alterations in the mycelia of C. lunata when treated with 7m at 50 µg/mL. Additionally, the preliminary structure-activity relationships (SARs) were also discussed. Thus, this study suggests that 4-aminoquinolines bearing a 1,3-benzodioxole moiety are interesting scaffolds for the development of novel antifungal agents.


Assuntos
Aminoquinolinas/farmacologia , Antifúngicos/farmacologia , Dioxóis/farmacologia , Fungos/efeitos dos fármacos , Aminoquinolinas/síntese química , Aminoquinolinas/química , Antifúngicos/síntese química , Antifúngicos/química , Dioxóis/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular
8.
Environ Toxicol ; 36(4): 675-685, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33270327

RESUMO

The application of silica nanoparticles (SiNPs) in areas of agriculture and medicine has raised great concerns for the potential adverse effects of SiNPs. The increasing toxicological studies focused mainly on the lung and cardiovascular system, but the adverse effects of SiNPs on nervous system have not been well explored. This study aimed to evaluate the role and mechanism of unfolded protein reaction (UPR) in SiNPs-induced cell injury on nerve cells in vitro. We investigated the UPR-mediated apoptosis caused by SiNPs in human neuroblastoma (SH-SY5Y) cell line. The size of SiNPs and its effect on cell ultrastructure were observed by transmission electron microscopy (TEM). Cell growth, mitochondrial membrane potential (MMP), calcium ion (Ca2+ ), apoptosis rate, and the expression level of related proteins were evaluated using MTT, flow cytometry, and western blot in SH-SY5Y cells exposed to SiNPs. The results showed that with the increase of SiNPs concentration, cell viability decreased, MMP decreased, active oxygen (ROS), and Ca2+ levels increased in a dose-dependent manner. In addition, protein expression of PERK, GRP78, and other related proteins in the unfolded protein response increased in a dose-response manner together with the expression of apoptosis proteins. Conclusively, this study confirmed that SiNPs can affect the neural system by interfering structure and functional and inducing apoptosis in nerve cells through unfolded protein response.


Assuntos
Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Nanopartículas/química , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/química
9.
Mol Divers ; 24(4): 1065-1075, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31705363

RESUMO

A series of 2-phenyl-4-aminoquinolines were designed, synthesized and evaluated for their antifungal activities against three phytopathogenic fungi in vitro. All of the target compounds were fully elucidated by 1H NMR, 13C NMR and HRMS spectra. The results indicated that most of the target compounds demonstrated significant activities against the tested fungi. Among them, compound 6e exhibited more promising inhibitory activities against C. lunata (EC50 = 13.3 µg/mL), P. grisea (EC50 = 14.4 µg/mL) and A. alternate (EC50 = 15.6 µg/mL), superior to azoxystrobin, a commercial agricultural fungicide. The structure-activity relationship (SAR) revealed that the aniline moiety at position 4 of the quinoline scaffold played a key role in the potency of a compound. And the substitution positions of the aniline moiety significantly influenced the activities. These encouraging results yielded a variety of 2-phenylquinolines bearing an aniline moiety acting as promising antifungal agents.


Assuntos
Aminoquinolinas/síntese química , Aminoquinolinas/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Compostos de Anilina/química , Fungos/efeitos dos fármacos , Fungicidas Industriais/síntese química , Fungicidas Industriais/farmacologia , Testes de Sensibilidade Microbiana , Pirimidinas/farmacologia , Quinolinas/química , Estrobilurinas/farmacologia , Relação Estrutura-Atividade
10.
Phys Chem Chem Phys ; 20(37): 24427-24433, 2018 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-30221300

RESUMO

Borophenes, which are two-dimensional boron counterparts made of the three synthetic polymorphs T, ß12 and χ3, have been considered as potential anode materials in Li-ion batteries with extremely high capacities. However, Li hopping on ß12 and χ3 borophenes is quite slow with high energy barriers (around 0.6 eV), thus preventing the application of these borophenes in the fast charging realm. Here, we have used halogen functionalization in an attempt to boost the sluggish Li-ion diffusion dynamics in the prototype χ3 borophene system. Halogens bind strongly to χ3 borophene with substantial electron transfer from the latter to the former, thereby leading to local electron deficiency in the χ3 borophene. The synergy of electron extraction from χ3 borophene and the electrostatic attraction between halogens and Li results in an enhanced affinity between χ3 borophene and Li as well as a reduction in the Li-ion hopping barrier. Iodine is the preferred dopant, for which most diffusion paths exhibit energy barriers typically smaller than 0.2 eV. Our results suggest that halogen incorporation could facilitate intercalation and de-intercalation of Li-ions in borophene-based anode materials.

11.
J Nanosci Nanotechnol ; 18(12): 8399-8402, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189966

RESUMO

A simple two-step aqueous method was employed to grow MgO nanostructures on ZnO/sapphire at low temperature. The obtained thin MgO nanostructures were uniformly distributed on the surface of ZnO layer and showed the sheet-like structures. Meanwhile, an ultraviolet (UV) photodetector based on ITO/MgO/ZnO structures was fabricated by simple way. The obtained UV detector showed excellent UV sensing properties. This novel method will greatly facilitate fabrication of large-scale metal-insulator-semiconductor with relatively low cost at remarkably low temperature.

12.
Sensors (Basel) ; 18(2)2018 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-29382155

RESUMO

In order to improve the sensing properties of tin dioxide gas sensor, four kinds of different SiO2/Al2O3 ratio, different particle size of MFI type zeolites (ZSM-5) were coated on the SnO2 to prepared zeolite modified gas sensors, and the gas sensing properties were tested. The measurement results showed that the response values of ZSM-5 zeolite (SiO2/Al2O3 = 70, grain size 300 nm) coated SnO2 gas sensors to formaldehyde vapor were increased, and the response to acetone decreased compared with that of SnO2 gas sensor, indicating an improved selectivity property. The other three ZSM-5 zeolites with SiO2/Al2O3 70, 150 and 470, respectively, and grain sizes all around 1 µm coated SnO2 sensors did not show much difference with SnO2 sensor for the response properties to both formaldehyde and acetone. The sensing mechanism of ZSM-5 modified sensors was briefly analyzed.

13.
Sensors (Basel) ; 17(8)2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28792433

RESUMO

In2O3/SnO2 composite hetero-nanofibers were synthesized by an electrospinning technique for detecting indoor volatile organic gases. The physical and chemical properties of In2O3/SnO2 hetero-nanofibers were characterized and analyzed by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), Energy Dispersive X-Ray Spectroscopy (EDX), specific surface Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS). Gas sensing properties of In2O3/SnO2 composite hetero-nanofibers were measured with six kinds of indoor volatile organic gases in concentration range of 0.5~50 ppm at the operating temperature of 275 °C. The In2O3/SnO2 composite hetero-nanofibers sensor exhibited good formaldehyde sensing properties, which would be attributed to the formation of n-n homotype heterojunction in the In2O3/SnO2 composite hetero-nanofibers. Finally, the sensing mechanism of the In2O3/SnO2 composite hetero-nanofibers was analyzed based on the energy-band principle.

14.
Physiol Mol Biol Plants ; 23(1): 125-134, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28250589

RESUMO

Ethylene-responsive factors (ERFs) are commonly considered to play an important role in pathogen defense responses. However, only few of ERF members have been characterized in Sea island cotton (Gossypium barbadense). Here, we reported a novel AP2/ERF transcription factors gene, named GbERFb which was cloned and identified from Sea island cotton by RACE. The expression of GbERFb was significantly induced by treatments with ethylene, Methyl jasmonate, salicylic acid, wounding, H2O2 and Verticillium dahliae (V. dahliae) infection. Bioinformatics analysis showed that GbERFb protein containing a conserved ERF DNA binding domain and a nuclear localization signal sequence, belonged to IXb subgroup of the ERF family. Further experiments demonstrated that GbERFb could bind the GCC box cis-acting element and interact with GbMAPKb (MAP kinase) directly in yeast. Over-expression of GbERFb in tobacco could increase the disease resistance to V. dahliae. The results suggest that the GbERFb, a new AP2/ERF transcription factor, could enhance the resistance to V. dahliae and be useful in improvement of crop resistance to pathogenes.

15.
Chem Res Toxicol ; 29(6): 972-80, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27124590

RESUMO

The development of a unique bioassay for cytotoxicity analysis of coal fly ash (CFA) particulate matter (PM) and its potential application for air quality monitoring is described. Using human cell lines, A549 and SK-MES-1, as live probes on microelectrode-embedded 96-well sensors, impedance changes over time are measured as cells are treated with varying concentrations (1 µg/mL-20 mg/mL) of CFA samples. A dose-dependent impedance change is determined for each CFA sample, from which an IC50 histogram is obtained. The assay was successfully applied to examine CFA samples collected from three coal-fired power plants (CFPs) in China. The samples were separated into three size fractions: PM2.5 (<2.5 µm), PM10-2.5 (2.5 µm < x < 10 µm), and PM10 (>10 µm). Dynamic cell-response profiles and temporal IC50 histograms of all samples show that CFA cytotoxicity depends on concentration, exposure time (0-60 h), and cell-type (SK-MES-1 > A549). The IC50 values differentiate the cytotoxicity of CFA samples based on size fraction (PM2.5 ≈ PM10-2.5 ≫ PM10) and the sampling location (CFP2 > CFP1 ≈ CFP3). Differential cytotoxicity measurements of particulates in human cell lines using cell-electronic sensing provide a useful tool for toxicity-based air quality monitoring and risk assessment.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Cinza de Carvão/química , Cinza de Carvão/toxicidade , Monitoramento Ambiental , Material Particulado/análise , Material Particulado/toxicidade , Poluentes Atmosféricos/química , Proliferação de Células/efeitos dos fármacos , Cinza de Carvão/análise , Relação Dose-Resposta a Droga , Humanos , Tamanho da Partícula , Material Particulado/química , Propriedades de Superfície , Fatores de Tempo , Células Tumorais Cultivadas
16.
Chemistry ; 20(27): 8458-66, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24895115

RESUMO

Our findings on the bifunctional squaramide-catalyzed enantioselective conjugate addition of ß-ketoamides to nitroolefins are disclosed. It appears that simple acyclic methylene ß-ketoamides, unlike the extensively studied ß-ketoesters, afford the products in excellent diastereoselectivities, and maintain high yields and enantioselectivities. Moreover, competition and kinetic studies were conducted to rationalize the observed reactivity and selectivity. The high level of diastereocontrol, along with the amenability of the amide group to postfunctionalization, dramatically increase the synthetic usefulness of the transformation.

17.
Environ Int ; 183: 108407, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38150806

RESUMO

Halobenzoquinones (HBQs) were recently discovered as an emerging class of drinking water disinfection byproducts with carcinogenic concern. However, the molecular mechanism underlying HBQs-induced DNA damage is not clear. In this study, we integrated in vitro genotoxicity, computational toxicology, and the quantitative toxicogenomic analysis of HBQs on DNA damage/repair pathways in human bladder epithelial cells SV-HUC-1. The results showed that HBQs could induce cytotoxicity with the descending order as 2,6-DIBQ > 2,6-DCBQ ≈ 2,6-DBBQ. Also, HBQs can increase DNA damage in SV-HUC-1 cells and thus generate genotoxicity. However, there is no significant difference in genotoxicity among the three HBQs. The results of molecular docking and molecular dynamics simulation further confirmed that HBQs had high binding fractions and stability to DNA. Toxicogenomic analysis indicated that HBQs interfered with DNA repair pathways, mainly affecting base excision repair, nucleotide excision repair and homologous recombination repair. These results have provided new insights into the underlying molecular mechanisms of HBQs-induced DNA damage, and contributed to the understanding of the relationship between exposure to DBPs and risks of developing bladder cancer.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Humanos , Desinfecção/métodos , Toxicogenética , Simulação de Acoplamento Molecular , Água Potável/análise , Dano ao DNA , Desinfetantes/toxicidade , Poluentes Químicos da Água/análise
18.
Environ Int ; 186: 108631, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38588609

RESUMO

Methylmercury (MeHg) is a global environmental pollutant with neurotoxicity, which can easily crosses the blood-brain barrier and cause irreversible damage to the human central nervous system (CNS). CNS inflammation and autophagy are known to be involved in the pathology of neurodegenerative diseases. Meanwhile, MeHg has the potential to induce microglia-mediated neuroinflammation as well as autophagy. This study aims to further explore the exact molecular mechanism of MeHg neurotoxicity. We conducted in vitro studies using BV2 microglial cell from the central nervous system of mice. The role of inflammation and autophagy in the damage of BV2 cells induced by MeHg was determined by detecting cell viability, cell morphology and structure, reactive oxygen species (ROS), antioxidant function, inflammatory factors, autophagosomes, inflammation and autophagy-related proteins. We further investigated the relationship between the inflammatory response and autophagy induced by MeHg by inhibiting them separately. The results indicated that MeHg could invade cells, change cell structure, activate NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome and autophagosome, release a large amount of inflammatory factors and trigger the inflammatory response and autophagy. It was also found that MeHg could disrupt the antioxidant function of cells. In addition, the inhibition of NLRP3 inflammasome alleviated both cellular inflammation and autophagy, while inhibition of autophagy increased cellular inflammation. Our current research suggests that MeHg might induce BV2 cytotoxicity through inflammatory response and autophagy, which may be mediated by the NLRP3 inflammasome activated by oxidative stress.


Assuntos
Autofagia , Inflamassomos , Inflamação , Compostos de Metilmercúrio , Microglia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Compostos de Metilmercúrio/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Autofagia/efeitos dos fármacos , Camundongos , Inflamassomos/metabolismo , Animais , Inflamação/induzido quimicamente , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos
19.
Environ Sci Technol ; 47(6): 2823-30, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23368424

RESUMO

Four halobenzoquinones (HBQs), 2,6-dichloro-1,4-benzoquinone (DCBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (DCMBQ), 2,3,6-trichloro-1,4-benzoquinone (TCBQ), and 2,6-dibromobenzoquinone (DBBQ), have been recently confirmed as disinfection byproducts (DBPs) in drinking water; however, their toxicological information is scarce. Here, we report that HBQs are cytotoxic to T24 bladder cancer cells and that the IC50 values are 95 µM for DCBQ, 110 µM for DCMBQ, 151 µM for TCBQ, and 142 µM for DBBQ, after a 24-h exposure. The antioxidant N-acetyl-l-cysteine (NAC) significantly reduces the cytotoxicity induced by the four HBQs, supporting the hypothesis that oxidative stress contributes to the cytotoxicity of HBQs. To further explore the oxidative mechanisms of cytotoxicity, we examined HBQ-induced production of reactive oxygen species (ROS) in T24 cells, and measured 8-hydroxydeoxyguanosine (8-OHdG), protein carbonyls, and malondialdehyde (MDA) adducts of proteins, markers of oxidative damage to DNA, proteins, and lipids, respectively. All four HBQs generated intracellular ROS in T24 cells in a concentration-dependent manner. HBQs also produced 8-OHdG in genomic DNA of T24 cells, with the highest levels of 8-OHdG induced by DCMBQ. Protein carbonylation was significantly increased in T24 cells that were incubated with each of the four HBQs for 24 h. However, MDA adduct formation, a marker of lipid peroxidation, was not affected by any of the four HBQs tested. These results suggest that the ROS-induced oxidative damage to DNA and protein carbonylation are involved in the observed toxicity of HBQs in T24 cells.


Assuntos
Benzoquinonas/toxicidade , Desinfetantes/toxicidade , Neoplasias da Bexiga Urinária/induzido quimicamente , 8-Hidroxi-2'-Desoxiguanosina , Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Benzoquinonas/química , Linhagem Celular Tumoral , Desoxiguanosina/análogos & derivados , Desoxiguanosina/análise , Desinfetantes/química , Água Potável/efeitos adversos , Água Potável/análise , Halogenação , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/análise , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Bexiga Urinária/citologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/metabolismo
20.
ChemSusChem ; 16(24): e202300708, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-37624682

RESUMO

Interphases, especially the electrochemically formed solid electrolyte interphase (SEI), are significantly important for cycling stability, reaction kinetics and safety of rechargeable batteries. The structure and composition of the electric double layer (EDL) greatly affect the formation of the SEI and the performance of electrodes. However, as far as we know, there is no review discussing the theme specifically. Herein, the recent substantial progress for EDL and its impact on the formation of SEI in rechargeable batteries are reviewed and discussed. Firstly, the specific adsorption of electrolyte components on electrodes' surface and the ionic solvation structure are introduced. Furthermore, various methods for controlling EDL in different electrode systems are described. Finally, the potential future advancements of the SEI through the manipulation of EDL are discussed, aiming to enhance the electrochemical performance of rechargeable batteries.

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