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1.
Artigo em Inglês | MEDLINE | ID: mdl-31374962

RESUMO

In situ injection of Fe(II)-activated persulfate was carried out to oxidize chlorinated hydrocarbons and benzene, toluene, ethylbenzene, and xylene (BTEX) in groundwater in a contaminated site in North China Plain. To confirm the degradation of contaminants, an oxidant mixture of persulfate, ferrous sulfate, and citric acid was mixed with the main contaminants including 1,2,3-trichloropropane (TCP) and benzene before field demonstration. Then the mixed oxidant solution of 6 m3 was injected into an aquifer with two different depths of 8 and 15 m to oxidize a high concentration of TCP, other kinds of chlorinated hydrocarbons, and BTEX. In laboratory tests, the removal efficiency of TCP reached 61.4% in 24 h without other contaminants but the removal rate was decreased by the presence of benzene. Organic matter also reduced the TCP degradation rate and the removal efficiency was only 8.3% in 24 h. In the field test, as the solution was injected, the oxidation reaction occurred immediately, accompanied by a sharp increase of oxidation-reduction potential (ORP) and a decrease in pH. Though the concentration of pollutants increased due to the dissolution of non-aqueous phase liquid (NAPL) at the initial stage, BTEX could still be effectively degraded in subsequent time by persulfate in both aquifers, and their removal efficiency approached 100%. However, chlorinated hydrocarbon was relatively difficult to degrade, especially TCP, which had a relatively higher initial concentration, only had a removal efficiency of 30%-45% at different aquifers and monitoring wells. These finding are important for the development of injection technology for chlorinated hydrocarbon and BTEX contaminated site remediation.


Assuntos
Água Subterrânea/química , Hidrocarbonetos Clorados/química , Propano/análogos & derivados , Sulfatos/química , Poluentes Químicos da Água/química , China , Recuperação e Remediação Ambiental , Oxirredução , Propano/química
2.
Chemosphere ; 236: 124342, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31326752

RESUMO

The growth of algae in water and the taste and odour compounds produced by algal metabolism present a threat to water quality, public health and aquatic ecosystems and cannot be effectively removed by conventional water treatment processes. In this paper, a hydroxyl radical (OH)-based drinking water treatment system (DWTS) with a capacity of 480 m3 per day was built in the Xinglin water plant, Xiamen, China. With pretreatment at 0.88 mg L-1, sand filtration, and disinfection at 0.31 mg L-1 during the conveyance of algae-laden water within only 9.8 s, OH removed all five kinds of algae, with a total content of 35,180 cells mL-1, while ClO2 treatment left live and dead algae at 7150 cells mL-1, which would be transported into the pipe networks for the drinking water supply. Meanwhile, OH degraded 2-Methylisoborneol (2-MIB) from 175 to 4.4 ng L-1, which was below the Chinese standard of 10 ng L-1, while ClO2 degraded 2-MIB only to 155 ng L-1. Based on analyses of the mass spectra database, OH could mineralize 2-MIB by opening the ring structures of 2,2-dimethyl-1,3-cyclopentanedione and 2-methyl-cyclohexenecarboxaldehyde to produce small-molecule compounds. After OH pretreatment and OH disinfection, all water quality and disinfection by-product indexes met the Chinese Sanitary Standards for Drinking Water. Therefore, OH advanced oxidation produced using strong ionization discharge could be practically applied for the degradation of 2-MIB during the treatment of algae-laden water in the OH DWTS.


Assuntos
/química , Compostos Clorados/química , Cianobactérias/metabolismo , Radical Hidroxila/análise , Óxidos/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , China , Diaminas/química , Desinfecção/métodos , Água Potável/química , Ecossistema , Filtração/métodos , Odorantes/análise , Oxirredução , Propano/análogos & derivados , Propano/química , Paladar , Qualidade da Água , Abastecimento de Água
3.
Int J Pharm ; 566: 652-661, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31181308

RESUMO

Pulmonary delivery is a highly attractive alternative to injections for biologics such as therapeutic proteins. However, bioavailabilities generally suffer from the presence of phagocytic cells that clear particulate matter entering the lung. In this study, microgel particles were developed using an all-aqueous two-phase system approach and evaluated for their efficacy as an inhalable controlled release system. Norbornene- and thiol-modified four- and eight-armed poly (ethylene glycol) with an average molecular mass of 10,000 Da were prepared as macromonomers for microgel formation. Emulsions of precursor solution droplets containing macromonomers and Irgacure 2959 as photocatalyst were prepared in a dextran solution. Irradiation with UV light was used to covalently crosslink the droplets by triggering the thiol-ene reaction. The resulting microgels were processed to dry powder inhaler formulations, and respirable aerodynamic sizes were assessed in vitro. Microgels were loaded with the model proteins lysozyme and bovine serum albumin, with encapsulation efficiencies of 51.5% and 73.6%, respectively. Depending on the macromonomer type, protein-loaded microgels released their cargo over a 6-14 day period. In an MTT assay, the particles did not show significant cytotoxicity, and their recognition by alveolar macrophages was considerably lower than for polystyrene control particles. This makes the microgels a promising pulmonary delivery system for proteins and other biologics.


Assuntos
Hidrogéis/administração & dosagem , Microesferas , Muramidase/administração & dosagem , Polietilenoglicóis/administração & dosagem , Soroalbumina Bovina/administração & dosagem , Administração por Inalação , Animais , Linhagem Celular , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Hidrogéis/química , Pulmão/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Camundongos , Muramidase/química , Fagocitose , Polietilenoglicóis/química , Propano/administração & dosagem , Propano/análogos & derivados , Propano/química , Propano/efeitos da radiação , Soroalbumina Bovina/química , Raios Ultravioleta
4.
Environ Toxicol ; 34(10): 1114-1120, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31231976

RESUMO

The aim of this study was designed to investigate the effects of rhynchophyllin (RH) on neuroinflammation in Tourette syndrome (TS) rats. TS model was established in rats by the injection of selective 5-HT2A/2C agonist 1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI). Behavior in DOI-induced rats was tested. Inflammatory cytokines levels such as interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in serum and striatum were detected. The expression levels of janus kinase 2 (JAK2)/signal transducer and transcription activator 3 (STAT3) and nuclear factor (NF)-κB pathways in striatum were measured by Western blot. Data indicated that RH can significantly reduce the numbers of nodding experiment of TS rats. RH significantly decreased IL-6, IL-1ß, and TNF-α in serum and striatum of TS rats, with altered expression of P-JAK2, P-STAT3, P-NF-κBp65, and P-IκBα in TS rats, as evidenced by Western blot analysis and immunohistochemistry, suggesting that the regulation of JAK2/STAT3 and NF-κB pathways might be involved in the mechanism of RH on TS.


Assuntos
Corpo Estriado/imunologia , Medicamentos de Ervas Chinesas/administração & dosagem , Janus Quinase 2/imunologia , Oxindois/administração & dosagem , Síndrome de Tourette/tratamento farmacológico , Uncaria/química , Animais , Corpo Estriado/efeitos dos fármacos , Humanos , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Janus Quinase 2/genética , Masculino , NF-kappa B/genética , NF-kappa B/imunologia , Propano/efeitos adversos , Propano/análogos & derivados , Ratos , Ratos Wistar , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Transdução de Sinais/efeitos dos fármacos , Síndrome de Tourette/induzido quimicamente , Síndrome de Tourette/genética , Síndrome de Tourette/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
5.
Appl Microbiol Biotechnol ; 103(16): 6837-6849, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31250061

RESUMO

1,2-Dichloroethane (1,2-DCA) is one of the most abundant manmade chlorinated organic contaminants in the world. Reductive dechlorination of 1,2-DCA by organohalide-respiring bacteria (OHRB) can be impacted by other chlorinated contaminants such as chloroethenes and chloropropanes that can co-exist with 1,2-DCA at contaminated sites. The aim of this study was to evaluate the effect of chloroethenes and 1,2-dichloropropane (1,2-DCP) on 1,2-DCA dechlorination using sediment cultures enriched with 1,2-DCA as the sole chlorinated compound (EA culture) or with 1,2-DCA and tetrachloroethene (PCE) (EB culture), and to model dechlorination kinetics. Both cultures contained Dehalococcoides as most predominated OHRB, and Dehalogenimonas and Geobacter as other known OHRB. In sediment-free enrichments obtained from the EA and EB cultures, dechlorination of 1,2-DCA was inhibited in the presence of the same concentrations of either PCE, vinyl chloride (VC), or 1,2-DCP; however, concurrent dechlorination of dual chlorinated compounds was achieved. In contrast, 1,2-DCA dechlorination completely ceased in the presence of cis-dichloroethene (cDCE) and only occurred after cDCE was fully dechlorinated. In turn, 1,2-DCA did not affect dechlorination of PCE, cDCE, VC, and 1,2-DCP. In sediment-free enrichments obtained from the EA culture, Dehalogenimonas 16S rRNA gene copy numbers decreased 1-3 orders of magnitude likely due to an inhibitory effect of chloroethenes. Dechlorination with and without competitive inhibition fit Michaelis-Menten kinetics and confirmed the inhibitory effect of chloroethenes and 1,2-DCP on 1,2-DCA dechlorination. This study reinforces that the type of chlorinated substrate drives the selection of specific OHRB, and indicates that removal of chloroethenes and in particular cDCE might be necessary before effective removal of 1,2-DCA at sites contaminated with mixed chlorinated solvents.


Assuntos
Bactérias/metabolismo , Microbiologia Ambiental , Poluentes Ambientais/metabolismo , Cloreto de Etil/metabolismo , Dicloretos de Etileno/metabolismo , Propano/análogos & derivados , Bactérias/classificação , Bactérias/genética , Biotransformação , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Oxirredução , Filogenia , Portugal , Propano/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Áreas Alagadas
6.
Org Lett ; 21(10): 3678-3681, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31038317

RESUMO

Horisfieldones A (1) and B (2), two dimeric diarylpropanes featuring an unprecedentedly aromatic ring-contracted framework, were isolated from Horsfieldia kingii. Their structures and absolute configurations were determined by the inspection of extensive spectroscopic data and electronic circular dichroism calculations. Molecular modeling analysis, in vitro enzyme-based bioassays, and structure-activity relationship analysis of these isolates revealed that (+)-1 (IC50 = 35.1 ± 3.9 µM, SI > 11.4) could present a new class of human DOPA decarboxylase inhibitor.


Assuntos
Dopa Descarboxilase/farmacologia , Propano/farmacologia , Dicroísmo Circular , Dopa Descarboxilase/química , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Propano/análogos & derivados , Propano/química , Relação Estrutura-Atividade
7.
Nat Chem ; 11(6): 578-586, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30988414

RESUMO

Polymerization reactions conducted inside cells must be compatible with the complex intracellular environment, which contains numerous molecules and functional groups that could potentially prevent or quench polymerization reactions. Here we report a strategy for directly synthesizing unnatural polymers in cells through free radical photopolymerization using a number of biocompatible acrylic and methacrylic monomers. This offers a platform to manipulate, track and control cellular behaviour by the in cellulo generation of macromolecules that have the ability to alter cellular motility, label cells by the generation of fluorescent polymers for long-term tracking studies, as well as generate a variety of nanostructures within cells. It is remarkable that free radical polymerization chemistry can take place within such complex cellular environments. This demonstration opens up a multitude of new possibilities for how chemists can modulate cellular function and behaviour and for understanding cellular behaviour in response to the generation of free radicals.


Assuntos
Radicais Livres/química , Polimerização/efeitos da radiação , Ácidos Polimetacrílicos/síntese química , Poliestirenos/síntese química , Acrilatos/química , Acrilatos/efeitos da radiação , Acrilatos/toxicidade , Citoesqueleto de Actina/efeitos dos fármacos , Compostos de Anilina/química , Compostos de Anilina/efeitos da radiação , Compostos de Anilina/toxicidade , Movimento Celular/efeitos dos fármacos , Fluorescência , Células HeLa , Humanos , Metacrilatos/química , Metacrilatos/efeitos da radiação , Metacrilatos/toxicidade , Propano/análogos & derivados , Propano/química , Propano/efeitos da radiação , Fase S/efeitos dos fármacos , Estirenos/química , Estirenos/efeitos da radiação , Estirenos/toxicidade , Raios Ultravioleta , Compostos de Vinila/química , Compostos de Vinila/efeitos da radiação , Compostos de Vinila/toxicidade
8.
Nutrients ; 11(4)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018609

RESUMO

Brassica vegetables such as cabbage or pak choi contain alkenyl glucosinolates which can release epithionitriles and to a lesser degree isothiocyanates upon enzymatic hydrolysis. Here, for the first time, the metabolism of an epithionitrile was investigated in humans, namely 1-cyano-2,3-epithiopropane (CETP). After consumption of Brassica oleracea var. capitata f. alba and Brassica carinata sprouts, the main urinary metabolite of CETP was identified as N-acetyl-S-(3-cyano-2-(methylsulfanyl)propyl-cysteine using an UHPLC-ESI-QToF-MS approach and synthesis of the metabolite. This urinary epithionitrile metabolite is an S-methylated mercapturic acid. No other metabolites were detected. Then, in a preliminary pilot experiment the excretion kinetics of CETP were investigated in three volunteers. After consumption of a B. carinata sprout preparation containing 50.8 µmol of CETP, urinary N-acetyl-S-(3-cyano-2-(methylsulfanyl)propyl-cysteine concentrations were the highest three hours after consumption, ranging from 23.9 to 37.2 µM, and declined thereafter. Thus, epithionitriles are bioavailable compounds that are metabolized similarly to isothiocyanates by the mercapturic acid pathway. In the future, more epithionitrile metabolites should be identified and the pharmacokinetics of these important class of dietary compounds should be assessed in more detail.


Assuntos
Acetilcisteína/análogos & derivados , Brassica/química , Nitrilos/metabolismo , Propano/análogos & derivados , Compostos de Sulfidrila/metabolismo , Acetilcisteína/química , Acetilcisteína/metabolismo , Acetilcisteína/urina , Humanos , Estrutura Molecular , Propano/metabolismo
9.
Environ Pollut ; 249: 305-310, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30901644

RESUMO

Swampy/septic odors are one of the most important odor types in drinking water. However, few studies have specifically focused on it compared to the extensive reported musty/earthy odor problems, even though the former is much more offensive. In this study, an investigation covering the odor characteristics, algal distribution and possible odorants contributing to swampy/septic odor, including dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), diisopropyl sulfide (DIPS), dipropyl sulfide (DPS), dibutyl sulfide (DBS), 2-methylisoborneol (2-MIB) and geosmin (GSM), was performed in source and finished water of 56 drinking water treatment plants (DWTPs) in 31 cities across China. While the musty/earthy and swampy/septic odors were dominant odor descriptors, the river source water exhibited a higher proportion of swampy/septic odor (38.5%) compared to much higher detection rate of musty/earthy odor (50.0%) in the lake/reservoir source water. The occurrence of swampy/septic odor, which was much easier to remove by conventional drinking water treatment processes compared to musty/earthy odors, was decreased by 62.9% and 46.3% in river and lake/reservoir source water respectively. Statistical analysis showed that thioethers might be responsible for the swampy/septic odor in source water (R2 = 0.75, p < 0.05). Specifically, two thioethers, DMDS and DMTS were detected, and other thioethers were not found in all water samples. DMDS was predominant with a maximum odor activity value (OAV) of 2.0 in source water and 1.3 in finished water. The distribution of the thioethers exhibited a marked regional characteristics with higher concentrations being detected in the east and south parts of China. The high concentrations of thioethers in lake/reservoir source water samples could be partly interpreted as the bloom of the cyanobacteria. This study provides basic information for swampy/septic odor occurrence in drinking water and will be helpful for further water quality management in water industry in China.


Assuntos
Água Potável/química , Odorantes/análise , Poluentes Químicos da Água/análise , Purificação da Água , China , Cidades , Água Potável/análise , Naftóis , Propano/análogos & derivados , Rios , Sulfetos/análise
10.
Int J Biol Macromol ; 126: 1030-1036, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30611805

RESUMO

It is highly desirable to develop biodegradable UV-shielding materials from the renewable resources as the ever-increasing demand for the sustainable environment. In this work, TiO2 decorated lignin particles (TiO2@lignin) were synthesized successfully by hydrothermal method in aqueous solution to improve the UV shielding performance of lignin particles. The poly(propylene carbonate) (PPC) composite films (thickness of ~23 µm) with different contents of TiO2@lignin were prepared via a blade-casting method. Morphological analysis showed that the TiO2@lignin dispersed uniformly in the PPC matrix with a good miscibility. UV-vis transmission spectra results revealed that the PPC composite film containing 5 wt% TiO2@lignin could absorb about 90% of UV light in the full UV band (200-400 nm), indicating the TiO2@lignin had a good UV-shielding property. Moreover, the presence of TiO2@lignin could significantly improve the thermal stability of the PPC/TiO2@lignin composite films. The DMA results showed that the introduction of TiO2@lignin could enhance the storage modulus and glass transition temperature simultaneously.


Assuntos
Materiais Biocompatíveis/química , Química Verde , Lignina/química , Propano/análogos & derivados , Titânio/química , Raios Ultravioleta , Varredura Diferencial de Calorimetria , Módulo de Elasticidade , Nanopartículas/química , Nanopartículas/ultraestrutura , Espectroscopia Fotoeletrônica , Propano/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Difração de Raios X
11.
Anticancer Agents Med Chem ; 19(3): 347-355, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30479221

RESUMO

BACKGROUND: Cancer can be considered as a disease in which normal cells start behaving badly, multiplying uncontrollably, ignoring signals to stop and accumulating to form a mass that is generally termed as a tumor. Apoptosis or programmed cell death is a physiological process that enables organisms to control their cell numbers in many developmental and physiological settings and to eliminate unwanted cells and it plays essential role in chemotherapy-induced tumor-cell killing. The correct balance between apoptosis and inhibition of apoptosis is important in animal development as well as in tissue homeostasis. The aim of this paper is to introduce the readers about the design strategy and synthesis of effective cytotoxic and apoptotic inducing agents based on benzo[d]imidazo[2,1-b]thiazole scaffold. METHODS: Benzo[d]imidazo[2,1-b]thiazole-propenone conjugates were synthesized by the condensation of 7- methoxy-2-(aryl)benzo[d]imidazo[2,1-b]thiazol-3-yl)prop-2-yn-1-ones with aryl/hetero aryl amines in ethanol at room temperature. These in turn were obtained from 7-methoxy-2-(aryl)benzo[d]imidazo[2,1-b]thiazole-3- carbaldehydes on treatment with ethynylmagnesium bromide followed by oxidation. RESULTS: 3-Arylaminopropenone linked 2-arylbenzo[d]imidazo[2,1-b]thiazole conjugates prepared in this investigation exhibited significant cytotoxic activity and arrested HeLa cancer cells in G1 phase. The treatment of the conjugate led to 40% of loss of mitochondrial membrane potential (DΨm) in HeLa cells and 4 fold increase in the levels of reactive oxygen species (ROS). In addition, it induces apoptosis in HeLa cells, this was examined by the wound healing assay, Actin filaments and Hoechst staining assay. CONCLUSION: The encouraging biological profile exhibited by these 3-arylaminopropenone 2-aryl linked benzo[d]imidazo[2,1-b]thiazole conjugates demonstrate that they have the potential to be developed as a lead by further structural modifications to obtain potential chemotherapeutic agents that are likely to target the HeLa cancer cells.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Imidazóis/farmacologia , Propano/farmacologia , Tiazóis/farmacologia , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazóis/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Propano/análogos & derivados , Propano/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Tiazóis/química , Cicatrização/efeitos dos fármacos
12.
J Cardiovasc Pharmacol Ther ; 24(3): 269-277, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30474386

RESUMO

Poly (propylene carbonate, PPC) is a new member of the aliphatic polyester family. An outstanding feature of PPC is that it produces mainly water and carbon dioxide when degraded in vivo, causing minimal side effects. This unique property together with excellent biocompatibility and biodegradability makes PPC a promising material for drug delivery. In this study, we explored the effect of the sirolimus (an inhibitor of cell growth)-eluting PPC mesh on graft stenosis and its possible mechanisms in a rat arteriovenous grafting model. The PPC mesh was prepared by electrospinning. A jugular vein to abdominal aortic autograft transplantation model was established in rats. The graft was then treated by wrapping with the drug mesh or the drug-free mesh or left untreated. Four weeks posttransplantation, neointima was measured with hematoxylin and eosin staining, matrix metalloproteinase-2 (MMP-2), and MMP-9, and proliferating cell nuclear antigen (PCNA) in the grafts were assayed by Western blotting and immunohistochemistry, respectively. In vitro rat aortic adventitial fibroblast cell (RAAFC) migration was assessed using the Boyden chamber assay, and phospho-mammalian target of rapamycin (mTOR) levels in RAAFCs were determined by Western blotting. Animals with the drug mesh had an intimal area index of 4.87% ± 0.98%, significantly lower than that of the blank group (14.21% ± 2.56%) or the PPC group (15.03% ± 2.35%, both P < .05). The sirolimus mesh markedly suppressed MMP-2 and MMP-9 expression, decreased PCNA-positive cell numbers, inhibited RAAFC migration, and reduced phospho-mTOR levels. Our data suggest that the sirolimus-eluting PPC mesh might be potentially applied for the management of grafting stenosis.


Assuntos
Aorta Abdominal/cirurgia , Fármacos Cardiovasculares/administração & dosagem , Materiais Revestidos Biocompatíveis , Oclusão de Enxerto Vascular/prevenção & controle , Veias Jugulares/transplante , Propano/análogos & derivados , Sirolimo/administração & dosagem , Telas Cirúrgicas , Enxerto Vascular/instrumentação , Animais , Autoenxertos , Movimento Celular , Desenho de Equipamento , Fibroblastos/metabolismo , Fibroblastos/patologia , Oclusão de Enxerto Vascular/metabolismo , Oclusão de Enxerto Vascular/patologia , Oclusão de Enxerto Vascular/fisiopatologia , Veias Jugulares/metabolismo , Veias Jugulares/patologia , Veias Jugulares/fisiopatologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Fosforilação , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Wistar , Serina-Treonina Quinases TOR/metabolismo , Enxerto Vascular/efeitos adversos , Grau de Desobstrução Vascular
13.
Nat Prod Res ; 33(20): 2958-2963, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30468086

RESUMO

Myristigranol, a new diarylpropane derivative, was isolated from the methanol extract of Myristica fragrans wood along with one diarylpropanoid and three stilbenoids. The isolated constituents were exhaustingly identified using the analyses of 1D and 2D NMR spectroscopic techniques and comparison of the literatures reported as well. The antioxidant activity was also determined.


Assuntos
Myristica/química , Propano/análogos & derivados , Madeira/química , Antioxidantes/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Propano/isolamento & purificação , Propano/farmacologia , Estilbenos/isolamento & purificação
14.
Molecules ; 23(10)2018 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-30347858

RESUMO

Traditional ionic liquids (ILs) catalysts suffer from the difficulty of product purification and can only be used in homogeneous catalytic systems. In this work, by reacting ILs with co-catalyst (ZnBr2), we successfully converted three polyether imidazole ionic liquids (PIILs), i.e., HO-[Poly-epichlorohydrin-methimidazole]Cl (HO-[PECH-MIM]Cl), HOOC-[Poly-epichlorohydrin-methimidazole]Cl (HOOC-[PECH-MIM]Cl), and H2N-[Poly-epichlorohydrin-methimidazole]Cl (H2N-[PECH-MIM]Cl), to three composite PIIL materials, which were further immobilized on ZSM-5 zeolite by chemical bonding to result in three immobilized catalysts, namely ZSM-5-HO-[PECH-MIM]Cl/[ZnBr2], ZSM-5-HOOC-[PECH-MIM]Cl/[ZnBr2], and ZSM-5-H2N-[PECH-MIM]Cl/[ZnBr2]. Their structures, thermal stabilities, and morphologies were fully characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The amount of composite PIIL immobilized on ZSM-5 was determined by elemental analysis. Catalytic performance of the immobilized catalysts was evaluated through the catalytic synthesis of propylene carbonate (PC) from CO2 and propylene oxide (PO). Influences of reaction temperature, time, and pressure on catalytic performance were investigated through the orthogonal test, and the effect of catalyst circulation was also studied. Under an optimal reaction condition (130 °C, 2.5 MPa, 0.75 h), the composite catalyst, ZSM-5-HOOC- [PECH-MIM]Cl/[ZnBr2], exhibited the best catalytic activity with a conversion rate of 98.3% and selectivity of 97.4%. Significantly, the immobilized catalyst could still maintain high heterogeneous catalytic activity even after being reused for eight cycles.


Assuntos
Imidazóis/química , Líquidos Iônicos/química , Propano/análogos & derivados , Zeolitas/química , Alcenos/química , Apatitas/química , Dióxido de Carbono/química , Catálise , Imidazóis/síntese química , Líquidos Iônicos/síntese química , Microscopia Eletrônica de Varredura , Propano/síntese química , Propano/química , Difração de Raios X
15.
Reprod Toxicol ; 82: 10-17, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30219569

RESUMO

Although equal numbers of X and Y spermatozoa are produced during spermatogenesis, the sex chromosome ratio in ejaculated spermatozoa can be altered by exposure to endocrine-disrupting chemicals (EDCs), which can be reflected by altered sex ratios at birth. Here, we hypothesized EDCs affect sperm functions and viability of X and Y chromosome-bearing human spermatozoa. After exposure to genistein (Gen), bisphenol A (BPA), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), dibromochloropropane (DBCP), and diazinon (Diaz), we evaluated motility, viability, capacitation, and differential viability of X and Y spermatozoa. All EDCs tested altered sperm viability, motility, and capacitation. Interestingly, the Y/X ratio of live spermatozoa was significantly lower in sperm treated with TCDD, DBCP, and Diaz than control spermatozoa. Our results suggest that some of EDCs have larger effects on the viability of Y spermatozoa than X spermatozoa, implicating that a reduction in Y sperm viability may result in a female-biased sex ratio of offspring at birth.


Assuntos
Cromossomos Humanos X , Cromossomos Humanos Y , Disruptores Endócrinos/toxicidade , Espermatozoides/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Diazinon/toxicidade , Genisteína/toxicidade , Humanos , Masculino , Fenóis/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Propano/análogos & derivados , Propano/toxicidade , Razão de Masculinidade , Motilidade Espermática/efeitos dos fármacos
16.
Molecules ; 23(9)2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30201888

RESUMO

We aimed to develop new effective catalysts for the synthesis of propylene carbonate from propylene oxide and carbon dioxide. A kind of Mx+LClx coordination complex was fabricated based on the chelating tridentate ligand 2,6-bis[1-(phenylimino)ethyl] pyridine (L). The obtained products were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. It was found that the catalytic activity of the complexes with different metal ions, the same ligand differed and co-catalyst, where the order of greatest to least catalytic activity was 2 > 3 > 1. The catalytic system composed of complex 2 and DMAP proved to have the better catalytic performance. The yields for complex 2 systems was 86.7% under the reaction conditions of 100 °C, 2.5 MPa, and 4 h. The TOF was 1026 h-¹ under the reaction conditions of 200 °C, 2.5 MPa, and 1 h. We also explored the influence of time, pressure, temperature, and reaction substrate concentration on the catalytic reactions. A hypothetical catalytic reaction mechanism is proposed based on density functional theory (DFT) calculations and the catalytic reaction results.


Assuntos
Dióxido de Carbono/química , Complexos de Coordenação/química , Compostos de Epóxi/química , Propano/análogos & derivados , Piridinas/química , Catálise , Cristalografia por Raios X , Reação de Cicloadição , Ligantes , Conformação Molecular , Propano/síntese química , Propano/química , Eletricidade Estática
17.
Ind Health ; 56(6): 561-565, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29973469

RESUMO

1,2-Dichloropropane (1,2-DCP) is used widely in Korea as a substitute for trichloroethylene or methylene chloride. Some companies mistakenly consider that 1,2-DCP is an eco-friendly detergent because its use is not regulated, but 1,2-DCP is known to inhibit the central nervous system in animals; a few cases of accidental exposure have been reported in humans. We present a case of acute encephalopathy caused by exposure to 1,2-DCP. A 41 yr-old male presented with dizziness, headache, and diplopia after exposure to the detergent without protective equipment. Brain magnetic resonance imaging suggested metabolic encephalopathy, but the patient had no thiamine deficiency and no other metabolic disorder. As the symptoms had commenced after exposure to a large amount of solvent while skimming rust from the surface, and as the symptoms were more severe during the work week, improved on weekends, and disappeared after solvent exposure ceased, the toxic encephalopathy was likely induced by inhalation of the detergent.


Assuntos
Síndromes Neurotóxicas/etiologia , Exposição Ocupacional/efeitos adversos , Propano/análogos & derivados , Solventes/toxicidade , Adulto , Encéfalo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Propano/toxicidade , República da Coreia
18.
Int J Mol Sci ; 19(7)2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30011782

RESUMO

The blends of Poly(propylene carbonate) (PPC) and polyester-based thermoplastic polyurethane (TPU) were melt compounded in an internal mixer. The compatibility, thermal behaviors, mechanical properties and toughening mechanism of the blends were investigated using Fourier transform infrared spectra (FTIR), tensile tests, impact tests, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and dynamic mechanical analysis technologies. FTIR and SEM examination reveal strong interfacial adhesion between PPC matrix and suspended TPU particles. Dynamic mechanical analyzer (DMA) characterize the glass transition temperature, secondary motion and low temperature properties. By the incorporation of TPU, the thermal stabilities are greatly enhanced and the mechanical properties are obviously improved for the PPC/TPU blends. Moreover, PPC/TPU blends exhibit a brittle-ductile transition with the addition of 20 wt % TPU. It is considered that the enhanced toughness results in the shear yielding occurred in both PPC matrix and TPU particles of the blends.


Assuntos
Plásticos Biodegradáveis/química , Polímeros/química , Poliuretanos/química , Propano/análogos & derivados , Varredura Diferencial de Calorimetria , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Propano/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Resistência à Tração
19.
Neuron ; 98(4): 801-816.e7, 2018 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-29706583

RESUMO

Monoaminergic modulation of cortical and thalamic inputs to the dorsal striatum (DS) is crucial for reward-based learning and action control. While dopamine has been extensively investigated in this context, the synaptic effects of serotonin (5-HT) have been largely unexplored. Here, we investigated how serotonergic signaling affects associative plasticity at glutamatergic synapses on the striatal projection neurons of the direct pathway (dSPNs). Combining chemogenetic and optogenetic approaches reveals that impeding serotonergic signaling preferentially gates spike-timing-dependent long-term depression (t-LTD) at thalamostriatal synapses. This t-LTD requires dampened activity of the 5-HT4 receptor subtype, which we demonstrate controls dendritic Ca2+ signals by regulating BK channel activity, and which preferentially localizes at the dendritic shaft. The synaptic effects of 5-HT signaling at thalamostriatal inputs provide insights into how changes in serotonergic levels associated with behavioral states or pathology affect striatal-dependent processes.


Assuntos
Corpo Estriado/metabolismo , Plasticidade Neuronal/genética , Receptores 5-HT4 de Serotonina/genética , Serotonina/metabolismo , Tálamo/metabolismo , Animais , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/genética , Corpo Estriado/citologia , Corpo Estriado/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Indóis/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Depressão Sináptica de Longo Prazo , Camundongos , Camundongos Transgênicos , Vias Neurais , Plasticidade Neuronal/efeitos dos fármacos , Optogenética , Piperidinas/farmacologia , Propano/análogos & derivados , Propano/farmacologia , Antagonistas do Receptor 5-HT4 de Serotonina/farmacologia , Sulfonamidas/farmacologia , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Tálamo/citologia , Tálamo/efeitos dos fármacos
20.
Eur J Pharmacol ; 830: 105-114, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29709439

RESUMO

Compounds containing a nitro group may reveal vasodilator properties. Several nitro compounds have a NO2 group in a short aliphatic chain connected to an aromatic group. In this study, we evaluated in rat aorta the effects of two nitro compounds, with emphasis on a putative recruitment of the soluble guanylate cyclase (sGC) pathway to induce vasodilation. Isolated aortic rings were obtained from male Wistar rats to compare the effects induced by 2-nitro-1-phenylethanone (NPeth) or 2-nitro-2-phenyl-propane-1,3-diol (NPprop). In aortic preparations contracted with phenylephrine or KCl, NPeth and NPprop induced vasorelaxant effects that did not depend on the integrity of vascular endothelium. NPeth had a lesser vasorelaxant efficacy than NPprop and only the NPprop effects were inhibited by pretreatment with the sGC inhibitors, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) or methylene blue. In an ODQ-preventable manner, NPprop inhibited the contractile component of the phenylephrine-induced response mediated by intracellular Ca2+ release or by extracellular Ca2+ recruitment through receptor- or voltage-operated Ca2+ channels. In contrast, NPprop was inert against the transient contraction induced by caffeine in Ca2+-free medium. In an ODQ-dependent manner, NPprop inhibited the contraction induced by the protein kinase C activator phorbol 12,13-dibutyrate or by the tyrosine phosphatase inhibitor sodium orthovanadate. In silico docking analysis of a sGC homologous protein revealed preferential site for NPprop. In conclusion, the nitro compounds NPeth and NPprop induced vasorelaxation in rat aortic rings. Aliphatic chain substituents selectively interfered in the ability of these compounds to induce vasorelaxant effects, and only NPprop relaxed aortic rings via a sGC pathway.


Assuntos
Aorta Torácica/efeitos dos fármacos , Guanilato Ciclase/metabolismo , Nitrocompostos/farmacologia , Propano/análogos & derivados , Vasodilatadores/farmacologia , Animais , Aorta Torácica/fisiologia , Guanilato Ciclase/fisiologia , Masculino , Propano/farmacologia , Ratos Wistar
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