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2.
Nat Commun ; 11(1): 4896, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994414

RESUMO

Natural biomolecules such as peptides and DNA can dynamically self-organize into diverse hierarchical structures. Mimicry of this homopolymer self-assembly using synthetic systems has remained limited but would be advantageous for the design of adaptive bio/nanomaterials. Here, we report both experiments and simulations on the dynamic network self-assembly and subsequent collapse of the synthetic homopolymer poly(propylene sulfone). The assembly is directed by dynamic noncovalent sulfone-sulfone bonds that are susceptible to solvent polarity. The hydration history, specified by the stepwise increase in water ratio within lower polarity water-miscible solvents like dimethylsulfoxide, controls the homopolymer assembly into crystalline frameworks or uniform nanostructured hydrogels of spherical, vesicular, or cylindrical morphologies. These electrostatic hydrogels have a high affinity for a wide range of organic solutes, achieving >95% encapsulation efficiency for hydrophilic small molecules and biologics. This system validates sulfone-sulfone bonding for dynamic self-assembly, presenting a robust platform for controllable gelation, nanofabrication, and molecular encapsulation.


Assuntos
Hidrogéis/síntese química , Polipropilenos/síntese química , Sulfonas/química , Alcenos/química , Hidrogéis/química , Interações Hidrofóbicas e Hidrofílicas , Polipropilenos/química , Eletricidade Estática
3.
Ecotoxicol Environ Saf ; 205: 111318, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979806

RESUMO

The retention of polyether sulfone (PES) and bisphenol A (BPA) in wastewater has received extensive attention. The effects of PES and BPA on the removal of organic matter by anaerobic granular sludge were investigated. We also analyzed the changes in the electron transport system and the effects on the composition of extracellular polymeric substances (EPS), as well as alternations of the microbial community in the anaerobic granular sludge. In the experimental groups which received BPA, the removal of the chemical oxygen demand (COD) were significantly suppressed, which an average removal efficiency of less than 65%, 30% lower than that of the control group. In the loosely-bound EPS (LB-EPS) excitation-emission matrix (EEM) spectra, the absorption peak of tryptophan disappeared when the BPA pollutants was added, which it was present in the control group without added pollutants. The addition of PES and BPA also affected protease, acetate kinase, and coenzyme F420 activities in the anaerobic granular sludge. Especially, the coenzyme F420 reduced from 0.0045 to 0.0017 µmol/L in the presence of PES and BPA. The relative abundance of Spirochaetes decreased in the presence of PES and BPA, while the relative abundance of Bacteroidetes increased from 12.98% to 22.87%. At the genus level, in the presence of PES and BPA, the relative abundance of Acinetobacter increased from 2.20% to 9.64% and Hydrogenophaga decreased sharply from 15.58% to 0.12%.


Assuntos
Compostos Benzidrílicos/análise , Microplásticos/análise , Fenóis/análise , Polímeros/química , Sulfonas/química , Eliminação de Resíduos Líquidos , Anaerobiose , Compostos Benzidrílicos/toxicidade , Análise da Demanda Biológica de Oxigênio , Matriz Extracelular de Substâncias Poliméricas , Microbiota/efeitos dos fármacos , Microplásticos/toxicidade , Fenóis/toxicidade , Plásticos , Esgotos/química , Águas Residuárias
4.
Chemosphere ; 261: 127687, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32750620

RESUMO

One of the major challenges facing the practical application of forward osmosis (FO) membranes is the need for high performance. Thus, the fabrication of highly permselective FO membranes is of great importance. The objective of this study was to improve the wettability/hydrophilicity of electrospun nanofiber (ESNF)-based substrates for the fabrication of nanofiber-supported thin film composite (NTFC) membranes for FO application. This study explored the impact of electrospun polyethersulfone/polyacrylonitrile (PES/PAN) nanofibers as the blend support to produce NTFC membranes. The blending of PES/PAN in the spinning dope was optimized. The blending of hydrophilic PAN (0-10 wt%) in PES affects the fiber diameter, hydrophilicity, water uptake, and roughness of the ESNF membrane substrates. Continuous thermal-rolling pretreatment was performed on the ESNF substrates prior to interfacial polymerization for polyamide active layer deposition. The results indicated that the fabricated NTFC membrane achieved significantly greater water flux (L/m2 h) while retaining a low specific salt flux (g/L) compared to traditional TFC membranes. The NTFC membrane flux increased with an increase in PAN content in the ESNF substrate. According to the FO performance results, the NTFC-10 (PES/PAN blend ratio of 90:10) exhibited optimal performance: a high water flux of 42.1 and 52.2 L/m2 h for the FO and PRO modes, respectively, and low specific salt flux of 0.27 and 0.24 g/L for the FO and PRO modes, respectively, using 1 M NaCl as the draw solution. This demonstrated the higher selectivity and water flux achieved by the developed NTFC membranes compared to the traditional TFC membranes.


Assuntos
Nanofibras/química , Polímeros/química , Sulfonas/química , Resinas Acrílicas , Interações Hidrofóbicas e Hidrofílicas , Estudos Longitudinais , Membranas Artificiais , Nylons , Osmose , Cloreto de Sódio , Água , Purificação da Água/métodos
5.
Chemosphere ; 261: 127762, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32738715

RESUMO

The presence of microplastics (MPs) and their effects have been widely investigated in the aquatic environment, whereas the research done in the terrestrial environment is incomparably lacking. MPs are considered a pollutant in soil on agricultural land, where they can act as a vector for other pollutants, namely organic chemical compounds, such as pesticides. In soil, presence of MPs is affecting the growth and life of microorganisms in it. The interactions between two types of MPs and three pesticides in the mixture with alluvial soil were studied. Adsorption of acetamiprid, chlorantraniliprole and flubendiamide in concentrations of 1, 5 and 10 mg L-1 onto polyester fibres and polypropylene particles of 0.5-1 mm size was studied at 1% and 5% (w/w) of their content in soil. Results showed that the adsorption of pesticides was dependent on their octanol/water partition coefficient, with the most highly adsorbed pesticide also being the most hydrophobic, regardless of the type and form of MPs. Adsorption of pesticides onto MP particles was confirmed in soil-MPs mixtures with 5% polypropylene and 5% polyester at all tested pesticides' concentrations, proving that MPs in soil systems act as carriers to pollutants. MPs in soil decreased the soil's intrinsic capacity to retain pesticides, indicating the possibility of a greater mobility of pesticides on MPs through the soil system.


Assuntos
Benzamidas/química , Microplásticos/química , Neonicotinoides/química , Poluentes do Solo/química , Sulfonas/química , ortoaminobenzoatos/química , Adsorção , Agricultura , Poluentes Ambientais , Praguicidas/química , Plásticos , Solo , Poluentes do Solo/análise
6.
Ecotoxicol Environ Saf ; 202: 110915, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800250

RESUMO

Benzobicyclon is a systemic herbicide that was officially registered in China in 2018. The environmental behaviors of benzobicyclon hydrolysate (BH), the main metabolite and active product of benzobicyclon, remain poorly understood in paddy fields. Here, agricultural soil samples were collected from paddy fields in Jiangxi (Ferralsols), Shandong (Alisols), Hebei (Luvisols), Heilongjiang (Phaeozems), Zhejiang (Anthrosols), Sichuan (Gleysols), Hainan (Plinthosols), and Hubei (Lixisols) across China. The equilibrium oscillation method was used to study the adsorption-desorption behaviors of BH in the eight soils. The relationships between BH adsorption and soil physicochemical properties, environmental factors (temperature and initial solution pH), and other external conditions (addition of humic acid, biochar, and metal ions) were quantified. The adsorption-desorption parameters of BH in all soils were well fitted by the Freundlich model. The adsorption constant of BH varied between 0.066 and 4.728. The BH adsorption capacity decreased in the following order: Phaeozems > Alisols > Ferralsols > Lixisols > Plinthosols > Anthrosols > Luvisols > Gleysols. The Freundlich adsorption and desorption constants of BH were linearly positively correlated with soil clay content (R2 = 0.711 and 0.709; P = 0.009 and 0.009, respectively), organic carbon content (R2 = 0.684 and 0.672; P = 0.011 and 0.013, respectively), and organic matter content (R2 = 0.698 and 0.683; P = 0.010 and 0.011, respectively); however, their linear relationships with soil cation exchange capacity were not significant (R2 = 0.192 and 0.192; P = 0.278 and 0.278, respectively). The adsorption and desorption constants of BH had negative, albeit not significant, correlations with soil pH (R2 = 0.104 and 0.100; P = 0.437 and 0.445, respectively). The adsorption of BH by soil occurred spontaneously and was mainly based on physical adsorption. Either low or high temperature reduced the ability of the soil to adsorb BH. The addition of humic acid to the soil increased BH adsorption, while the addition of biochar increased the solution pH, resulting in decreased BH adsorption. Cation type and ionic strength also had strong effects on BH adsorption. With the exception of Phaeozems, BH exhibited intermediate or high mobility in the agricultural soils and thus poses risks to surface water and groundwater.


Assuntos
Compostos Bicíclicos com Pontes/química , Herbicidas/química , Poluentes do Solo/química , Sulfonas/química , Adsorção , Agricultura , China , Argila , Água Subterrânea , Herbicidas/análise , Solo/química , Poluentes do Solo/análise
7.
Bull Environ Contam Toxicol ; 105(2): 261-269, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32666192

RESUMO

Persistence and sorption behaviour of flubendiamide in two different Indian soils as affected by maize stalk biochar was studied. The persistence was more in West Bengal soil (178.6 days) than Sikkim soil (165.3 days) at 10 µg g-1 fortification level. Biochar amendment addition to soil at 5% enhanced the degradation process and half-life (T1/2) values were 103.5 and 117.4 days, respectively for biochar amended Sikkim and West Bengal soil. Sorption study through batch equilibrium method resulted the 4 h equilibrium time with adsorption 6.22% ± 0.16% and 5.26% ± 0.16% in Sikkim and West Bengal soil, respectively. Biochar addition at 5% increased the adsorption of flubendiamide to 8.12% ± 0.16% and 5.88% ± 0.16% indicating a greater influence in this process. The adsorption was more in biochar amended Sikkim soil than West Bengal soil. The values of desorption was slower than adsorption indicating a hysteresis effect having hysteresis coefficient (H1) ranges between 0.025 and 0.151 in two test soils.


Assuntos
Benzamidas/química , Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química , Sulfonas/química , Adsorção , Benzamidas/análise , Biomassa , Carvão Vegetal/economia , Solo , Poluentes do Solo/análise , Sulfonas/análise , Zea mays
8.
PLoS One ; 15(7): e0236529, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697797

RESUMO

In this study, functionalized multi-walled carbon nanotubes (MWCNT-NH2) were synthesized as an additive for the preparation of mixed matrix membranes (MMMs) and then were investigated by FTIR and FE-SEM techniques. Polyether sulfone (PES) polymeric membrane modified with functionalized MWCNT-NH2 carbon nanotubes was prepared by phase inversion method. The effect of MWCNT-NH2 on the morphology and property of the PES membrane was evaluated using scanning electron microscopy. The flux, enrichment factor and swelling properties of modified membranes were also used to investigate the membranes performance. The results showed that the flux and enrichment factor in modified PES membrane containing 5 wt.% of functionalized MWCNT-NH2 carbon nanotubes were obtained 1.2 L.m-2h-1 and 3.3, respectively. The influence of methanol concentration on the flux and enrichment factor was investigated. The results corroborated that the flux didn't change significantly, while the enrichment factor was decreased.


Assuntos
Membranas Artificiais , Nanotubos de Carbono/química , Polímeros/química , Sulfonas/química , Metanol/química , Porosidade , Água/química , Purificação da Água/métodos
9.
Ann N Y Acad Sci ; 1475(1): 43-51, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32483859

RESUMO

There is a significant need to study the binding of active compounds to the specific sites on insect ryanodine receptors (RyRs) that are the targets of two novel classes of diamide insecticides to which insects are becoming increasingly resistant. Here, we describe a rapid assay to study the action of potential compounds on the flubendiamide (Flu) binding site of insect RyRs that uses a fluorescence polarization assay with the fluorescence probe Flu-R-L that we synthesized. The IC50 of Flu for inhibiting probe binding on insect RyR was 18.82 ng/mL. The binding of 86 novel phthalic diamide derivatives on insect RyRs was studied using this newly established assay, and the compounds that exhibited high-affinity binding in the assay also possessed in vivo insecticidal activity against Plutella xylostella. Thus, Flu-R-L is a highly selective and sensitive fluorescence probe for studying the binding affinity of novel compounds to the Flu binding site of insect RyRs. The assay based on Flu-R-L is a rapid, accurate, and sensitive method for the screening of potentially bioactive molecules that bind specifically to insect RyRs.


Assuntos
Corantes Fluorescentes/metabolismo , Mariposas/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Animais , Benzamidas/química , Sítios de Ligação , Bioensaio , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Cinética , Pirazóis/química , Reprodutibilidade dos Testes , Sulfonas/química , ortoaminobenzoatos/química
10.
Chemosphere ; 256: 127099, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470733

RESUMO

Membrane fouling is an issue of concern due to the hydrophobic properties of polyethersulfone (PES) membrane when applied in water treatment. In this work, a facile hydrothermal method was utilized to synthesize hierarchical flower-like structured molybdenum disulfide nanosheets (HF-MoS2 NSs) that then incorporated into PES membranes as composite membranes. We characterized their permeability, the separation performance, the antifouling performance, and the antibacterial activity systematically. Results showed that composite membranes exhibited a better pure water flux (286 LMH/bar) at the HF-MoS2 NSs content of 0.4 wt%, which was 1.8 times higher than the control membrane. Also, composite PES membranes achieved 98.2% and 96.9% rejection of BSA and HA in comparison with the control PES membrane (87.3%, and 84.5%, respectively). Compare to the control PES membrane, the flux recovery ratio of the composite membrane increased from 69% to 88% for BSA fouling and increased from 84% to 93% for HA fouling. The retention rate for the organic dyes also improved slightly after HF-MoS2 NSs incorporation into the membrane. Additionally, the composite membranes exhibited a relatively high antibacterial activity against E. coli and B. subtilis with antibacterial rates of 67.8% and 82.5%, respectively. In conclusion, HF-MoS2 NSs incorporated composite membranes were shown to have outstanding filtration performance and could be a promising candidate for practical application in water filtration.


Assuntos
Nanoestruturas/química , Polímeros/química , Sulfonas/química , Purificação da Água/métodos , Dissulfetos/química , Escherichia coli , Filtração , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Molibdênio/química , Permeabilidade , Água/química
11.
Eur J Med Chem ; 194: 112269, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32248002

RESUMO

RAS-RAF pathway presents a valuable target for the cancer treatment due to its important roles in the regulation of tumor proliferation, apoptosis and the obtained resistance. To explore such target a RAS/CRAF interference agent, was therefore conjugated with Pt(IV) prodrugs via ester bond, resulting in total eleven multifunctional Pt(IV) complexes. The complexes could target genomic DNA and disrupt the signaling transduction from RAS protein to CRAF so that block the mitogen-activated protein kinase (MAPK) signaling pathway. Experiments in vitro indicated that all of the Pt(IV) complexes showed potent anti-tumor activity with IC50 values ranged from 8 nM to 22.55 µM, which were significantly improved as compared with cisplatin (CDDP) whose IC50 values ranged from 5.45 µM to 9.05 µM. Among them, 26 exerted the best anti-tumor activity in vitro, which not only exhibited excellent cytotoxicity against normal tumor cells, but also against CDDP-resistance cell lines (e.g. A549/CDDP and SKOV-3/CDDP). Importantly, 26 only showed little effect on normal cell lines such as HUEVC and LO2. Besides, the following biological mechanisms studies demonstrated that 26 could efficiently enter. A549 cells, significantly arrest cell cycle at G2/M phase, disrupt the signaling pathway and trigger endogenous caspase apoptosis pathway. Furthermore, results of a xenograft subcutaneous model of A549 tumor showed that 26 could effectively decrease tumor growth rates without causing loss of bodyweight.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glicina/análogos & derivados , Compostos Organoplatínicos/farmacologia , Sulfonas/farmacologia , Quinases raf/antagonistas & inibidores , Proteínas ras/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cisplatino/farmacologia , Dano ao DNA , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glicina/química , Glicina/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonas/química , Quinases raf/metabolismo , Proteínas ras/metabolismo
12.
J Chromatogr A ; 1619: 460953, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32178861

RESUMO

A solid phase microextraction coupled with flash evaporation gas chromatography method was applied to the determination of phthalate esters (PAEs). Polysulfone (PSF) hollow fiber at 1 cm length was employed as extraction element to adsorb PAEs directly. Predominant parameters including stirring velocity, salt concentration, extraction time and extraction temperature were optimized. PSF fiber with absorbed PAEs was put into a small sample cup. The extracted analytes were thermally desorbed at 300 °C in a pyrolyzer, and then entered into a column for separation. The linearity of the method was satisfactory over a concentration range of 2-1000 µg/L with the correlation coefficients r>0.99 for all analytes except dimethoxyethyl phthalate. The relative standard deviations for peak areas were below 9.5% (n = 6). The developed technique achieved high enrichment factors (280-9930 times) and low limits of detection (0.001-0.130 µg/L). The recoveries over the range of 87.0-117.7% were obtained by analyzing real spiked samples. The results demonstrated that this was a simple, environmentally friendly and accurate method for the determination of PAEs in bottled water samples.


Assuntos
Cromatografia Gasosa , Água Potável/química , Ésteres/isolamento & purificação , Ionização de Chama , Análise de Alimentos/métodos , Polímeros/química , Microextração em Fase Sólida , Sulfonas/química , Adsorção , Ésteres/análise , Ácidos Ftálicos/isolamento & purificação , Temperatura
13.
J Chromatogr A ; 1620: 461000, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32173026

RESUMO

This work focused on the development and validation of a method based on hollow fiber-based solid-phase microextraction coupled to ultra-performance liquid chromatography tandem mass spectrometry (HF-based-SPME-UPLC-MS/MS) for the determination of five antipsychotics at a pg mL-1 level in human whole blood and urine. Four types of hollow fiber membrane materials, including polyether sulfone, polypropylene, polyvinyl chloride and polyvinylidene fluoride were investigated. Finally, polyether sulfone hollow fiber without any modification was selected as the adsorption medium for solid-phase microextraction (SPME) with the following extraction procedure: the analytes were adsorbed onto the hollow fiber in the sample bottle with application of ultrasonication. Subsequently, the hollow fiber was transferred into a slim glass tube containing an appropriate solvent, and the analytes were desorbed by ultrasound treatment before detection by UPLC-MS/MS. In order to obtain satisfactory extraction efficiency, extraction parameters such as hollow fiber membrane material, pH, hollow fiber length, extraction time, desorption solvent and desorption time were investigated. Under the optimum experimental conditions, this method allowed for determination of five antipsychotics in human whole blood with excellent limits of quantification (LOQs) (25.0, 12.5, 25.0, 25.0 and 12.5 pg mL-1 for perphenazine, chlorpromazine, chlorprothixene, promethazine and trifluoperazine, respectively). The corresponding LOQs in human urine were 25.0, 12.5, 12.5, 12.5 and 12.5 pg mL-1 for the respective antipsychotics. The precision (RSD) was no more than 13.3%. The extraction recoveries for human whole blood and urine were in the range of 46.4-96.6% and 65.2-101.9%, respectively. The proposed method was compared with other methods from the literature and the results demonstrate that it is a simple, sensitive, efficient and green technique. It is suitable for analyzing trace target analytes in complex matrices such as biological samples and can provide a reliable tool for drug monitoring especially in forensic analysis and case of drug abuse.


Assuntos
Antipsicóticos/análise , Cromatografia Líquida/métodos , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Adsorção , Adulto , Antipsicóticos/sangue , Antipsicóticos/isolamento & purificação , Antipsicóticos/urina , Feminino , Humanos , Microextração em Fase Líquida/métodos , Polímeros/química , Reprodutibilidade dos Testes , Solventes , Sulfonas/química
14.
Chemistry ; 26(32): 7258-7262, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32128894

RESUMO

Reaction of (R)-3,3'-diformyl-1,1'-bi-2-naphthol with concentrated sulfuric acid gives the corresponding 6,6'-disulfonated compound (R)-2 selectively. This provides a simple and efficient method to convert a water-insoluble compound to a water-soluble fluorescent probe. It is found that (R)-2 in combination with Zn2+ shows a highly enantioselective fluorescent response toward various amino acids in the aqueous HEPES buffer solution at pH 7.4. For example, an enantioselective fluorescence enhancement ratio [ef=ΔID /ΔIL ] up to 35.8 is observed for the recognition of asparagine. NMR and mass spectroscopic investigations are conducted to explore the reaction of (R)-2 with asparagine.


Assuntos
Aminoácidos/química , Corantes Fluorescentes/química , Naftóis/química , Sulfonas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Fluorescência , Estereoisomerismo , Água , Zinco/química
15.
J Am Chem Soc ; 142(7): 3392-3400, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32009391

RESUMO

Targeted covalent modification of surface-exposed lysines is challenging due to their low intrinsic reactivity and high prevalence throughout the proteome. Strategies for optimizing the rate of covalent bond formation by a reversibly bound inhibitor (kinact) typically involve increasing the reactivity of the electrophile, which increases the risk of off-target modification. Here, we employ an alternative approach for increasing kinact of a lysine-targeted covalent Hsp90 inhibitor, independent of the reversible binding affinity (Ki) or the intrinsic electrophilicity. Starting with a noncovalent ligand, we appended a chiral, conformationally constrained linker, which orients an arylsulfonyl fluoride to react rapidly and enantioselectively with Lys58 on the surface of Hsp90. Biochemical experiments and high-resolution crystal structures of covalent and noncovalent ligand/Hsp90 complexes provide mechanistic insights into the role of ligand conformation in the observed enantioselectivity. Finally, we demonstrate selective covalent targeting of cellular Hsp90, which results in a prolonged heat shock response despite concomitant degradation of the covalent ligand/Hsp90 complex. Our work highlights the potential of engineering ligand conformational constraints to dramatically accelerate covalent modification of a distal, poorly nucleophilic lysine on the surface of a protein target.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lisina/química , Sulfonas/farmacologia , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP90/química , Humanos , Ligantes , Estereoisomerismo , Sulfonas/síntese química , Sulfonas/química
16.
J Appl Oral Sci ; 28: e20190156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049134

RESUMO

OBJECTIVE: The present study aimed to investigate the participation of focal adhesion kinases (FAK) in interactions between osteoblastic cells and titanium (Ti) surfaces with three different topographies, namely, untreated (US), microstructured (MS), and nanostructured (NS). METHODOLOGY: Osteoblasts harvested from the calvarial bones of 3-day-old rats were cultured on US, MS and NS discs in the presence of PF-573228 (FAK inhibitor) to evaluate osteoblastic differentiation. After 24 h, we evaluated osteoblast morphology and vinculin expression, and on day 10, the following parameters: gene expression of osteoblastic markers and integrin signaling components, FAK protein expression and alkaline phosphatase (ALP) activity. A smooth surface, porosities at the microscale level, and nanocavities were observed in US, MS, and NS, respectively. RESULTS: FAK inhibition decreased the number of filopodia in cells grown on US and MS compared with that in NS. FAK inhibition decreased the gene expression of Alp, bone sialoprotein, osteocalcin, and ALP activity in cells grown on all evaluated surfaces. FAK inhibition did not affect the gene expression of Fak, integrin alpha 1 ( Itga1 ) and integrin beta 1 ( Itgb1 ) in cells grown on MS, increased the gene expression of Fak in cells grown on NS, and increased the gene expression of Itga1 and Itgb1 in cells grown on US and NS. Moreover, FAK protein expression decreased in cells cultured on US but increased in cells cultured on MS and NS after FAK inhibition; no difference in the expression of vinculin was observed among cells grown on all surfaces. CONCLUSIONS: Our data demonstrate the relevance of FAK in the interactions between osteoblastic cells and Ti surfaces regardless of surface topography. Nanotopography positively regulated FAK expression and integrin signaling pathway components during osteoblast differentiation. In this context, the development of Ti surfaces with the ability to upregulate FAK activity could positively impact the process of implant osseointegration.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Osteoblastos/efeitos dos fármacos , Quinolonas/farmacologia , Sulfonas/farmacologia , Titânio/química , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Proteína-Tirosina Quinases de Adesão Focal/análise , Proteína-Tirosina Quinases de Adesão Focal/química , Expressão Gênica , Integrinas/análise , Microscopia Eletrônica de Varredura , Osseointegração/efeitos dos fármacos , Osteoblastos/fisiologia , Quinolonas/química , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Sulfonas/química , Propriedades de Superfície
17.
Chemosphere ; 244: 125386, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050321

RESUMO

Polysulfone ultrafiltration (UF) and polypiperazine-amide nanofiltration (NF) membranes were first fabricated by phase inversion and interfacial polymerization, and then modified by the commonly used TiO2 on the membrane surface, respectively. Compared with the pristine UF and NF membranes, pure water flux decreased by 40.66% for modified UF membrane and 12.92% for modified NF membrane, while the contact angle of the modified membranes decreased from 66.5° to 35.3° for UF membrane and from 48.2° to37.7° for NF membrane. However, the membrane modified by TiO2 nanoparticles for both UF and NF membranes exhibited much better anti-fouling and separation performance for two types of oil-in-water emulsions with different droplet size (i.e., prepared oil-in-water emulsion with low salinity and oil produced water in Shengli oilfield, China). It was obvious that water flux of modified UF only slightly decreased and the stable water flux was 2.2 times and 15.6% higher than that of pristine membranes for the prepared oil-in-water emulsion and produced water, respectively. According to the five fouling models for UF, the TiO2 modified UF membrane could alleviate the fouling on membrane surface and greatly increase water flux by reducing the adsorption, deposition, blockage of membrane pores and formation of cake layer for two types of oil-in-water emulsion. For NF, water flux of the modified membrane increased by 66.1% and 22.8% for prepared oil-in-water emulsion and produced water, respectively. TiO2 coating effectively alleviated the oil adhesion and cake layer formation on the membrane surface.


Assuntos
Emulsões/química , Membranas Artificiais , Poluição por Petróleo , Piperazina/química , Polímeros/química , Sulfonas/química , Purificação da Água/métodos , China , Emulsões/isolamento & purificação , Óleos Industriais , Nanopartículas , Campos de Petróleo e Gás , Ultrafiltração/métodos , Ultrafiltração/normas
18.
Eur J Med Chem ; 191: 112139, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32109777

RESUMO

Since our study showed that sulfone derivatives' action mode creates a lesser risk of inducing widespread resistance among Candida spp., we continued verifying sulfones' antifungal activity using the following newly synthesized derivatives: bromodichloromethy-4-hydrazinyl-3-nitrophenyl sulfone (S1), difluoroiodomethyl-4-hydrazinyl-3-nitrophenyl sulfone (S2), and chlorodifluoromethyl-4-hydrazinyl-3-nitrophenyl sulfone (S3). As the mechanism by which sulfones gain access to the cytoplasm has not been elucidated yet, in order to track S1-3, we coupled their hydrazine group with BODIPY (final S1-3 BODIPY-labelled were named SB1-3). This approach allowed us to follow the vital internalization and endocytic routing of SB1-3, while BODIPY interacts primarily with fungal surfaces, thus confirming that S1-3 and their counterparts SB1-2 behaved as non-typical agents by damaging the cell membrane and wall after being endocytosed (SB1-3 fluorescence visible inside the unlysed sessile cells). Thus greatly decreasing the likelihood of the appearance of strains resistance. Core sulfones S1-3 are a promising alternative not only to treat planktonic C. albicans but also biofilm-embedded cells. In the flow cytometric analysis, the planktonic cell surface was digested by S1-3, which made the externalized PS accessible to AnnexinV binding and PI input (accidental cell death ACD). The occurrence of ACD as well as apoptosis (crescent-shaped nuclei) and anoikis of sessile cells (regulated cell death by 100%-reduction in attachment to epithelium) was assessed through monitoring the AO/PI/HO342 markers. CLSM revealed the invasion of S1-3 and SB1-3 in C. albicans without inducing cell lysis. This was a novel approach in which QCM-D was used for real-time in situ detection of viscoelastic changes in the C. albicans biofilm, and its interaction with S1 as a representative of the sulfones tested. S1 (not toxic in vivo) is a potent fungicidal agent against C. albicans and could be administered to treat invasive candidiasis as a monotherapy or in combination with antifungal agents of reference to treat C. albicans infections.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Sulfonas/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonas/síntese química , Sulfonas/química
19.
Colloids Surf B Biointerfaces ; 188: 110769, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31918157

RESUMO

Polysulfone (PSf) membrane is widely employed in blood purification fields, but the blood compatibility of PSf membrane is not adequate. To improve the hemocompatibility of PSf membrane, 4-(chloromethyl)benzoic acid (CMBA) and sulfonated hydroxypropyl chitosan (SHPCS) were grafted onto PSf membrane surface. In our strategy, CMBA was firstly grafted on the PSf membrane surface through the Friedel-Crafts alkylation reaction, and the product was named BAPSf membrane. Then, SHPCS was grafted onto the BAPSf membrane surface by esterification, and the product was named SHPCS-BAPSf membrane. The effects of temperature and reaction time on the productivity of BAPSf and the grafting density of carboxyl and the effects of reaction time on the grafting density of SHPCS grafted onto the BAPSf membrane surface were studied. The SHPCS-BAPSf membranes are investigated by ATR-FTIR, XPS, contact angle measurements and evaluated by blood compatibility in vitro. The results reveal that the hydrophilicity of SHPCS-BAPSf membranes were grealy improved and the evaluation of protein adsorption, hemolysis test, platelet adhesion plasma recalcification time(PRT), activated partial thromboplastin time(APTT), prothrombin time(PT) and thrombin time(TT) confirmed that the SHPCS-BAPSf membranes have remarkable blood compatibility.


Assuntos
Ácido Benzoico/química , Materiais Biocompatíveis/química , Quitosana/química , Polímeros/química , Sulfonas/química , Adsorção , Animais , Testes de Coagulação Sanguínea , Plaquetas/química , Bovinos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Tamanho da Partícula , Adesividade Plaquetária , Soroalbumina Bovina/química , Propriedades de Superfície
20.
Molecules ; 25(2)2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31936021

RESUMO

The molybdenum (Mo)-catalyzed oxidation of sulfide under neutral conditions yields sulfone. This reaction proceeds more smoothly than olefin epoxidation and primary or secondary alcohol oxidation. In this study, Mo-catalyzed oxidation was used to screen for sulfur compounds (named "MoS-screening") in microbial broths by liquid chromatography-mass spectrometry (LC/MS). To demonstrate proof-of-concept, known sulfur microbial compounds were successfully identified from a mixture of non-sulfur microbial compounds as sulfinyl or sulfonyl products of Mo-catalyzed oxidation. Then our MoS-screening method was used to screen 300 samples of microbial broth for sulfur compounds. One of the identified compounds was a kitasetaline-containing N-acetyl cysteine moiety produced by an actinomycete strain. These results demonstrate the potential of MoS-screening in the search for new sulfur compounds from microbial sources.


Assuntos
Actinobacteria/metabolismo , Molibdênio/química , Sulfonas/química , Compostos de Enxofre/química , Acetilcisteína/química , Actinobacteria/química , Actinobacteria/crescimento & desenvolvimento , Catálise , Cromatografia Líquida , Fermentação , Espectrometria de Massas , Oxirredução , Sulfetos/química , Enxofre/química
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