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1.
Food Chem ; 302: 125326, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416003

RESUMO

Ruminant meat is considered an excellent source of proteins, dietary fatty acids and essential minerals. Grilling is a popular cooking method; however, the high temperatures employ could modify the grilled meat quality and safety. In this study, the effects of novel beer-based marinades infused with herbs and spices on the quality, safety, and sensory perception of grilled beef and moose meat is examined. Unmarinated meat showed high content of volatile lipid oxidation and Maillard reaction products compared to the marinated samples, which contained higher number and abundance of terpenes and sulfur based compounds. Strong relationships between Maillard products and heterocyclic amines formation, as well as between volatile terpenes and the lipophilic antioxidant activity, were observed in the grilled meats. The findings suggest the unfiltered beer-based marinades were effective in reducing lipid oxidation and Maillard reaction compounds formation, while improving the nutritional quality, safety and sensory preference of grilled ruminant meats.


Assuntos
Cerveja , Culinária/métodos , Carne , Ruminantes , Adolescente , Adulto , Aminas/análise , Aminas/química , Animais , Bovinos , Qualidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Compostos Heterocíclicos/análise , Temperatura Alta , Humanos , Reação de Maillard , Carne/análise , Pessoa de Meia-Idade , Valor Nutritivo , Carne Vermelha , Especiarias , Paladar , Compostos Orgânicos Voláteis/análise
2.
J Agric Food Chem ; 67(40): 11129-11136, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31487456

RESUMO

4-Amion-2,2,6,6-tetramethylpiperidine (Temp) was grafted into sodium lignosulfonate (SL) to obtain hindered amine-modified lignosulfonate (SL-Temp). Then, the polymer surfactant (SL-Temp-CTAB) was prepared using cetyltrimethylammonium bromide (CTAB) and SL-Temp. Obtained SL-Temp-CTAB was used as an emulsifier to prepare a green emulsifiable concentrate (EC) of avermectin (AVM), which shows good emulsifying property and storage stability. The prepared AVM green EC can form AVM-loaded microspheres with nanometer particle size distribution after emulsification in water. After ultraviolet irradiation for 70 h, the AVM retention rate of the green EC prepared using SL-Temp-CTAB was 75.8%, which is much higher than that of commercial EC (0.4%) and the green EC prepared using unmodified SL (31.4%). Moreover, the AVM green EC prepared using SL-Temp-CTAB has slow-release performance, and the release equilibrium time is 5.3 times the commercial EC. Therefore, the newly prepared AVM green EC using a lignin-based functional emulsifier shows good antiphotolysis and slow-release performance compared to the traditional EC.


Assuntos
Aminas/química , Emulsificantes/síntese química , Lignina/química , Cetrimônio/química , Emulsificantes/química , Emulsões/química , Cinética , Lignina/análogos & derivados , Espectroscopia de Ressonância Magnética , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Chem Commun (Camb) ; 55(71): 10567-10570, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31417998

RESUMO

Macrocyclization of linear peptide precursors using the Petasis borono-Mannich reaction affords a diverse range of macrocycles with an endocyclic amine. Analysis of the corresponding macrocyclic structures underscores that the hydrogen bond between an endocyclic amine and the adjacent amide NH is a powerful control element for conformationally homogenous peptide macrocycles.


Assuntos
Ácidos Borônicos/química , Compostos Macrocíclicos/síntese química , Peptídeos Cíclicos/síntese química , Aldeídos/química , Amidas/química , Aminas/química , Aziridinas/química , Ciclização
4.
Chem Commun (Camb) ; 55(71): 10627-10630, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31429450

RESUMO

We report the synthesis of a novel hydroxyl-functionalised heteroleptic bis-NHC gold(i) complex that permits conjugation to various amines via carbamate bond formation. The resulting derivatives were studied in vitro using cell proliferation assays and fluorescent microscopic imaging of human cancer cell lines.


Assuntos
Aminas/química , Antineoplásicos/síntese química , Carbamatos/química , Complexos de Coordenação/síntese química , Corantes Fluorescentes/síntese química , Ouro/química , Células A549 , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Doxorrubicina/química , Humanos , Imagem Óptica , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Triazóis/química
5.
J Chem Theory Comput ; 15(9): 4982-5000, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31411469

RESUMO

In this work, we report the development of Drude polarizable force field parameters for the carboxylate and N-acetyl amine derivatives, extending the functionality of the existing Drude polarizable carbohydrate force field. The force field parameters have been developed in a hierarchical manner, reproducing the quantum mechanical gas-phase properties of small model compounds representing the key functional group in the carbohydrate derivatives, including optimization of the electrostatic and bonded parameters. The optimized parameters were then used to generate the models for carboxylate and N-acetyl amine carbohydrate derivatives. The transferred parameters were further tested and optimized to reproduce crystal geometries and J-coupling data from nuclear magnetic resonance experiments. The parameter development resulted in the incorporation of d-glucuronate, l-iduronate, N-acetyl-d-glucosamine (GlcNAc), and N-acetyl-d-galactosamine (GalNAc) sugars into the Drude polarizable force field. The parameters developed in this study were then applied to study the conformational properties of glycosaminoglycan polymer hyaluronan, composed of d-glucuronate and N-acetyl-d-glucosamine, in aqueous solution. Upon comparing the results from the additive and polarizable simulations, it was found that the inclusion of polarization improved the description of the electrostatic interactions observed in hyaluronan, resulting in enhanced conformational flexibility. The developed Drude polarizable force field parameters in conjunction with the remainder of the Drude polarizable force field parameters can be used for future studies involving carbohydrates and their conjugates in complex, heterogeneous systems.


Assuntos
Aminas/química , Carboidratos/química , Simulação de Dinâmica Molecular , Teoria Quântica , Eletricidade Estática
6.
Food Chem ; 298: 125048, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260953

RESUMO

Heterocyclic aromatic amines (HAAs) are harmful by-products naturally formed during the heating process of foodstuffs. The present work reported an analytical method for HAAs analysis for the first time in bakery products by QuEChERS technique combined with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Bakery products were ultrasonically extracted with acetonitrile and sodium hydroxide solution (1 mmol/L). The obtained extracting solution was nearly dried under nitrogen stream and subsequently purified by QuEChERS technique using primary secondary amine (PSA) as adsorbents. Fourteen HAAs were separated on a C18 column with the mobile phase of a mixture of acetonitrile and 1 mmol/L ammonium acetate water solution (containing 0.04% acetic acid), and detected by MS/MS under multiple reaction monitoring (MRM) mode. The developed method was validated in terms of linearity, matrix effect, accuracy and precision. The method showed a good linearity (R2 > 0.999) for all analytes in their corresponding concentration ranges. The method limit of quantifications (LOQs, S/N = 10) of 14 HAAs were in the range of 0.3-4.5 µg/kg. The average recoveries (n = 6) at 3 spiked levels ranged from 62.8 to 96.8% with relative standard deviations (RSDs) of 1.2-7.6%. The validated method was applied in HAAs analysis in 20 bakery products and 4 kinds of HAAs (harman, norharman, AaC, PhIP) were detected with the concentrations ranging from 0.6 to 35.6 µg/kg.


Assuntos
Aminas/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Aminas/química , Pão/análise , Compostos Heterocíclicos/química , Limite de Detecção , Reprodutibilidade dos Testes
7.
Anal Chim Acta ; 1078: 200-211, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31358220

RESUMO

The effect of the ionization in the RP-HPLC retention of 66 acid-base compounds, most of them drugs of pharmaceutical interest, is studied. The retention time of the compounds can be related to the pH measured in the mobile phase (pwsH) through the sigmoidal equations derived from distribution of the neutral and ionic forms of the drug into the stationary and mobile phases. Fitting of the obtained retention vs. pH profiles provides the retention times of the ionic and neutral forms and the pKa values of the drugs in the mobile phase (pwsKa). The obtained pwsKa values are linearly correlated to the pKa values in water (pwwKa) with two different correlations, one for neutral acids and another for neutral bases that reflect the different influence of the dielectric constant of the medium in ionization of acids and bases. The retention of the neutral species is well correlated to the octanol-water partition coefficient of the drugs as measure of the lipophilicity of the drug, which affects chromatographic retention. Also, the retention time of the ionized forms is related to the retention time of the neutral forms by two different linear correlations, one for anions and the other for cations. These last correlations point out the different retention behaviour of anions and cations: anions are less retained than cations of the same lipophilicity, as measured by the octanol-water partition coefficient of the neutral form. The different retention behaviour of anionic, cationic and neutral forms is confirmed by the hold-up times obtained from different approaches: pycnometry and retention times of anionic (KBr and KI) and neutral (DMSO) markers. Hold-up times obtained by pycnometric measurements agree with those obtained by retention of neutral markers (0.83-0.85 min), whereas hold-up time for anions is mobile phase pH dependent. At acidic pH it is similar to the hold-up time for neutral markers (0.83 min), but then it decreases with the increase of mobile phase pH to 0.65 min at pH 11. The decrease can be explained by the ionization of the silanols of the column and exclusion of anions by charge repulsion. Although not directly measured, the obtained retention data and correlations indicate hold-up time for cations are similar or slightly lower than hold-up time for neutral compounds (0.77-0.83 min). The model proposed and the correlations obtained can be very useful for its implementation in retention prediction algorithms for optimization of separation purposes.


Assuntos
Aminas/química , Ácidos Carboxílicos/química , Fenóis/química , Piridinas/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Modelos Químicos
8.
J Enzyme Inhib Med Chem ; 34(1): 1178-1185, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31282230

RESUMO

The activation of the ß-class carbonic anhydrases (CAs, EC 4.2.1.1) from the bacteria Brucella suis and Francisella tularensis with amine and amino acids was investigated. BsuCA 1 was sensitive to activation with amino acids and amines, whereas FtuCA was not. The most effective BsuCA 1 activators were L-adrenaline and D-Tyr (KAs of 0.70-0.95 µM). L-His, L-/D-Phe, L-/D-DOPA, L-Trp, L-Tyr, 4-amino-L-Phe, dopamine, 2-pyridyl-methylamine, D-Glu and L-Gln showed activation constants in the range of 0.70-3.21 µM. FtuCA was sensitive to activation with L-Glu (KA of 9.13 µM). Most of the investigated compounds showed a weak activating effect against FtuCA (KAs of 30.5-78.3 µM). Many of the investigated amino acid and amines are present in high concentrations in many tissues in vertebrates, and their role in the pathogenicity of the two bacteria is poorly understood. Our study may bring insights in processes connected with invasion and pathogenic effects of intracellular bacteria.


Assuntos
Aminas/farmacologia , Aminoácidos/farmacologia , Brucella suis/enzimologia , Anidrases Carbônicas/metabolismo , Ativação Enzimática/efeitos dos fármacos , Francisella tularensis/enzimologia , Aminas/química , Aminoácidos/química , Anidrases Carbônicas/genética , Relação Estrutura-Atividade
9.
J Enzyme Inhib Med Chem ; 34(1): 1210-1217, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31286781

RESUMO

In this study, a series of 4,5-bis(substituted phenyl)-4H-1,2,4-triazol-3-amine compounds was designed, synthesised, and evaluated to determine their potential as anti-lung cancer agents. According to the results of screening of lung cancer cell lines A549, NCI-H460, and NCI-H23 in vitro, most of the synthesised compounds have potent cytotoxic activities with IC50 values ranging from 1.02 to 48.01 µM. Particularly, compound 4,5-bis(4-chlorophenyl)-4H-1,2,4-triazol-3-amine (BCTA) was the most potent anti-cancer agent, with IC50 values of 1.09, 2.01, and 3.28 µM against A549, NCI-H460, and NCI-H23 cells, respectively, meaning many-fold stronger anti-lung cancer activity than that of the chemotherapeutic agent 5-fluorouracil. We also explored the effects of BCTA on apoptosis in lung cancer cells by flow cytometry and western blotting. Our results indicated that BCTA induced apoptosis by upregulating proteins BAX, caspase 3, and PARP. Thus, the potential application of compound BCTA as a drug should be further examined.


Assuntos
Aminas/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Triazóis/síntese química , Triazóis/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Triazóis/química
10.
J Chromatogr A ; 1603: 141-149, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31277951

RESUMO

Ethyleneamines have been produced and commercialized for decades in the chemical industry for a diverse range of applications. The presence of amine functional groups provides them opportunity to adsorb onto surfaces which can make them a very challenging sample matrix to analyze using separation techniques. In the present report, a new aqueous SEC-RI method, which enables MWD characterization of higher ethyleneamines, is described. The sample preparation was based on the dilute-and-shoot methodology. A surface-modified SEC column with positively charged groups attached to the stationary phase was used. The mobile phase composition (salt concentration, pH) was optimized to suppress interaction between the ethyleneamines and the packing material. Very symmetrical peak shapes were achieved for low MW monodisperse ethyleneamines despite their high primary amine content. MWD calculations were conducted using conventional narrow standard calibration with partial linear extrapolation of the calibration curve. The narrow standards were of the same chemistry as the samples of interest. Consequently, the standard components display a consistent behaviour towards the column packing as the sample components which makes the present method more robust and the interpretation of the quantitative results more convenient. Effect on the measured MW averages and MW distribution due to various experimental parameters (e.g., system variability, mobile phase preparation, sample concentration) were investigated showing good repeatability (RSD < 2%) for Mn, Mw, and Mz.


Assuntos
Aminas/química , Cromatografia em Gel/métodos , Aminas/síntese química , Calibragem , Peso Molecular , Padrões de Referência , Água/química
11.
Chemphyschem ; 20(16): 2110-2121, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31265754

RESUMO

The physicochemical properties and transfection efficacies of two samples of a cationic lipid have been investigated and compared in 2D (monolayers at the air/liquid interface) and 3D (aqueous bulk dispersions) model systems using different techniques. The samples differ only in their chain composition due to the purity of the oleylamine (chain precursor). Lipid 8 (using the oleylamine of technical grade for cost-efficient synthesis) shows lateral phase separation in the Langmuir layers. However, the amount of attached DNA, determined by IRRAS, is for both samples the same. In 3D systems, lipid 8 p forms cubic phases, which disappear after addition of DNA. At physiological temperatures, both lipids (alone and in mixture with cholesterol) assemble to lamellar aggregates and exhibit comparable DNA delivery efficiency. This study demonstrates that non-lamellar structures are not compulsory for high transfection rates. The results legitimate the utilization of oleyl chains of technical grade in the synthesis of cationic transfection lipids.


Assuntos
Aminas/química , DNA/química , Lipídeos/química , Lipossomos/química , Aminas/síntese química , Aminas/normas , Aminas/toxicidade , Animais , Bovinos , Linhagem Celular Tumoral , Colesterol/química , Técnicas de Transferência de Genes/normas , Humanos , Lipídeos/síntese química , Lipídeos/normas , Lipídeos/toxicidade , Lipossomos/normas , Lipossomos/toxicidade , Estrutura Molecular , Transição de Fase , Suínos , Transfecção/normas , Temperatura de Transição
12.
Radiat Res ; 192(2): 219-230, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31246533

RESUMO

Primary amines form a key component of a well-studied mechanism for capturing carbon dioxide (CO2) from the atmosphere. This study comprises a single-step synthesis of a novel sorbent for CO2 by grafting monomers rich in primary amines to three commercial-grade fabrics: polyethylene terephthalate, high-density polyethylene and nylon 6. An initial evaluation of the sorbency of the chosen monomers, allylamine and butenylamine, qualitatively confirmed their ability to extract CO2 from the atmosphere. Six novel copolymers, comprised of each of the three fabrics grafted with one of each monomer, were synthesized using radiation-induced graft copolymerization through electron beam irradiation. All fabrics achieved greater grafting with butenylamine compared to allylamine, likely given the closer proximity of the primary amine to the radical on the latter's structure. Primary amines can stabilize radicals, preventing copolymerization reactions. Characterization of sorbency revealed that the majority of the grafted amines likely reacted to adsorb CO2. Therefore, the amount of amine grafted comprises the primary limiting factor on the sorbents' CO2 capacity.


Assuntos
Atmosfera/química , Dióxido de Carbono/química , Polimerização , Têxteis , Adsorção , Aminas/química , Técnicas de Química Sintética , Radioquímica
13.
J Chromatogr A ; 1602: 107-116, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31182304

RESUMO

Polystyrene is one of the best candidates as the extracting medium due to its high stability in different media and acceptable extraction capability. However, the hydrophobic nature and low wettability of polystyrene limits its application to non-polar analytes. To resolve this limitation, in this project, amine groups were chemically attached to the surface of magnetic polystyrene. The resulting hydrophilic magnetic particles were expected to be capable of extracting both polar and non-polar analytes. Non-steroidal anti-inflammatory drugs (NSAIDs) were chosen for testing the applicability of modified magnetic polystyrene according to the importance of their analysis and also their wide polarity range. Major parameters associated with the extraction procedure were optimized using central composite design (CCD) method and pH 3, extraction time of 15 min, desorption volume of 350 µL and desorption time of 4 min were chosen as optimized values. Under these conditions, figures of merit were calculated including: linear dynamic range (0.5-1000 µg L-1), linear equation and limits of detection (0.1-3 µg L-1). To investigate the method precision, inter-day, intra-day and synthesis-to-synthesis relative standard deviation (RSD) were studied (<12%). All studies were conducted using blank urine samples spiked with aspirin, salicylic acid, ibuprofen, diclofenac and mefenamic acid. Naproxen was chosen as the internal standard and high-performance liquid chromatography-UV-Vis (HPLC-UV) was employed for the subsequent determination after extraction. To evaluate the applicability of the method for real sample analysis, urine samples from patients under treatment were analyzed and acceptable results were obtained. The aminated magnetic polystyrene revealed superior extraction efficiency, much higher than polystyrene before functionalization. In addition, hospital wastewater sample was tested and acceptable extraction efficiencies were obtained.


Assuntos
Aminas/química , Magnetismo , Preparações Farmacêuticas/isolamento & purificação , Preparações Farmacêuticas/urina , Poliestirenos/química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/urina , Diclofenaco/química , Diclofenaco/urina , Humanos , Ibuprofeno/química , Ibuprofeno/urina , Limite de Detecção , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias/química
14.
Food Chem ; 293: 529-536, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151644

RESUMO

The effect of glucose oxidase (GOx) catalytic oxidation on the efficacy of gallic acid (GA) to modify the chemical structure and gelling behavior of myofibrillar protein (MP) was investigated. In contrast to non-oxidized MP samples where GA induced very little changes, GA (0, 6, 30, and 60 µmol/g MP) under GOx treatment promoted sulfhydryl and amine loss (up to 58% and 49%, respectively). The attenuation of intrinsic tryptophan fluorescence in the GA/GOx-treated MP corroborated the finding. The gelling capacity of MP, corresponding to disulfide and non-disulfide bond formation in protein aggregates, was markedly enhanced by 60 µmol GA under GOx, up to 86% in gel storage modulus G' and 53% in gel strength. The GOx-aided GA modification of MP could be a potential ingredient strategy in meat processing to promote textural attributes of cooked products.


Assuntos
Ácido Gálico/química , Géis/química , Glucose Oxidase/metabolismo , Proteínas Musculares/química , Aminas/química , Aminas/metabolismo , Animais , Ácido Gálico/metabolismo , Carne/análise , Microscopia Eletrônica de Varredura , Proteínas Musculares/metabolismo , Oxirredução , Reologia , Compostos de Sulfidrila/química , Compostos de Sulfidrila/metabolismo
15.
J Agric Food Chem ; 67(28): 8045-8052, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31241326

RESUMO

n-Octadecylamine was adopted as a cleanup agent to develop a novel solidification of a switchable solvent-based QuEChERS method. At higher temperatures (such as 55 °C), n-octadecylamine can melt into a liquid, allowing effective extraction of matrix interferences in acetonitrile solution (i.e., in dispersive liquid-liquid microextraction). At lower temperatures, n-octadecylamine carrying matrix interferences can rapidly solidify and easily separate from the acetonitrile solution. The results demonstrated that n-octadecylamine possessed a better ability to remove matrix interferences and reduce matrix effects than those of traditional solid-phase dispersive extraction cleanup agents of primary secondary amine and octadecyl bonded silica gel. By coupling it with gas chromatography-mass spectrometry, the proposed method was applied to the detection of 16 pesticides in cucumber. The recoveries were from 80.9 to 112.6% with relative standard deviations less than 12.9%. Satisfactory results were also obtained for the detection of 16 pesticides in pear, orange, apple, pepper, lettuce, and tomato.


Assuntos
Frutas/química , Microextração em Fase Líquida/métodos , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Verduras/química , Acetonitrilos/química , Aminas/química , Citrus sinensis/química , Cucumis sativus/química , Cromatografia Gasosa-Espectrometria de Massas , Alface/química , Microextração em Fase Líquida/instrumentação , Lycopersicon esculentum/química , Malus/química , Solventes/química
16.
Environ Sci Pollut Res Int ; 26(24): 25130-25141, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31254198

RESUMO

Amine-modified diatomite with remarkable formaldehyde (HCHO) removal efficiency was prepared by grafting 3-aminopropyltrimethoxysilane (APTMS) in this research. The interfacial properties and microstructures of the prepared adsorbents were characterized and analyzed. The HCHO adsorption properties of the amine modified diatomite were also systematically studied, and it has been proven to be effective adsorbent with better adsorption performance than activated carbon for the removal of gaseous HCHO. Furthermore, to better explain the experimental results, we performed density functional theory (DFT) study on the adsorption system and calculated the geometry, energy, and charge parameters based on first principles. Also, the underlying adsorption mechanism was proposed detailedly by combining experimentation with DFT calculation, suggesting that amine modified diatomite can be efficient adsorbent for the elimination of gaseous formaldehyde.


Assuntos
Aminas/química , Carvão Vegetal/química , Terra de Diatomáceas/química , Formaldeído/análise , Adsorção , Teoria da Densidade Funcional , Formaldeído/química , Gases
17.
Int J Nanomedicine ; 14: 4229-4245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239677

RESUMO

Purpose: Gene therapies via Noggin small interfering (si)RNA (siNoggin) and bone morphogenetic protein (BMP)-2 plasmid DNA (pBMP-2) may be promising strategies for bone repair/regeneration, but their ideal delivery vectors, efficacy difference, and underlying mechanisms have not been explored, so these issues were probed here. Methods: This study used lipopolysaccharide-amine nanopolymersomes (LNPs), an efficient cytosolic delivery vector developed by the research team, to mediate siNoggin and pBMP-2 to transfect MC3T3-E1 cells, respectively. The cytotoxicity, cell uptake, and gene knockdown efficiency of siNoggin-loaded LNPs (LNPs/siNoggin) were studied, then the osteogenic-differentiation efficacy of MC3T3-E1 cells treated by LNPs/pBMP-2 and LNPs/siNoggin, respectively, were compared by measuring the expression of osteogenesis-related genes and proteins, alkaline phosphatase (ALP) activity, and mineralization of the extracellular matrix at all osteogenic stages. Finally, the possible signaling pathways of the two treatments were explored. Results: LNPs delivered siNoggin into cells efficiently to silence 50% of Noggin expression without obvious cytotoxicity. LNPs/siNoggin and LNPs/pBMP-2 enhanced the osteogenic differentiation of MC3T3 E1 cells, but LNPs/siNoggin was better than LNPs/pBMP-2. BMP/Mothers against decapentaplegic homolog (Smad) and glycogen synthase kinase (GSK)-3ß/ß-catenin signaling pathways appeared to be involved in osteogenic differentiation induced by LNPs/siNoggin, but GSK-3ß/ß-catenin was not stimulated upon LNPs/pBMP-2 treatment. Conclusion: LNPs are safe and efficient delivery vectors for DNA and RNA, which may find wide applications in gene therapy. siNoggin treatment may be a more efficient strategy to enhance osteogenic differentiation than pBMP-2 treatment. LNPs loaded with siNoggin and/or pBMP-2 may provide new opportunities for the repair and regeneration of bone.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Proteínas de Transporte/metabolismo , Diferenciação Celular , Lipopolissacarídeos/farmacologia , Nanopartículas/química , Osteogênese , Polímeros/química , RNA Interferente Pequeno/administração & dosagem , Fosfatase Alcalina/metabolismo , Aminas/química , Animais , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Matriz Extracelular/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Minerais/química , Nanopartículas/toxicidade , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Plasmídeos/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Transfecção , beta Catenina/metabolismo
18.
Food Chem ; 297: 125027, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253341

RESUMO

The structure and the cation-exchange functional groups of hybrid silica materials were evaluated for the effective detoxification of hydroalcoholic solutions containing eight toxic biogenic amines (BA) usually found in fermented beverages. Results show the effectiveness of the removal is related to the number of amino functions in the extracted molecule, retention by the solid being more effective in the case of multiple amino groups, since retention is stabilized through interaction with the material surface at several points. BA with one amino function (isoamylamine, tyramine, ß-phenylethylamine), in general, showed a weak retention by the solids. For BA with more than two amine groups (spermine, spermidine), the removal rate was close to 100% for all studied materials. For histamine, cadaverine and putrescine, the removal percentages were higher with a lamellar structured sulfonic acid functionalized material and with bifunctional materials (SBA-15 type and macroporous) containing sulfonic/phosphonic acid groups obtained by co-condensation sol-gel route.


Assuntos
Aminas Biogênicas/química , Dióxido de Silício/química , Adsorção , Aminas/química , Aminas Biogênicas/análise , Cadaverina/química , Cromatografia Líquida de Alta Pressão , Géis/química , Histamina/química , Espectrometria de Massas , Porosidade , Putrescina/química , Espermidina/química , Espermina/química , Ácidos Sulfônicos/química , Propriedades de Superfície , Tiramina/química
19.
Eur J Med Chem ; 179: 38-55, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31233921

RESUMO

Indoleamine 2, 3-dioxygenase 1 (IDO1) plays a key role in tryptophan catabolism which is an important mechanism in immune tolerance. The small molecule epacadostat is the most advanced IDO1 inhibitor, but its phase III trials as a single agent or in combinations with PD-1 antibody failed to show appreciable objective responses. To gain more insight on the antitumor efficacy of IDO1 inhibitors, we have designed a series of analogues of epacadostat by incorporating a cyclic aminosulfonamide moiety as the sidechain capping functionality. Compound 5a was found to display significant potency against recombinant hIDO1 and hIDO1 expressed HEK293 cancer cells. This compound has improved physico-chemical properties, acceptable PK parameters as well as optimal cardiac safety. Similar to epacadostat, 5a is ineffective as single agent in the CT-26 syngeneic xenograft model, however, the combination of 5a with PD-1 antibody showed both elevated tumor growth inhibition and prolonged median life span.


Assuntos
Aminas/farmacologia , Antineoplásicos/farmacologia , Desenho de Drogas , Inibidores Enzimáticos/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Oxidiazóis/farmacologia , Aminas/síntese química , Aminas/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Feminino , Células HEK293 , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Oxidiazóis/síntese química , Oxidiazóis/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
20.
J Chromatogr A ; 1601: 310-318, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31054832

RESUMO

Efficient separation of aromatic amine isomers is a challenging issue in chemical industry and environmental analysis. Here we report the use of p-amino-tetradecyloxy-calix[4]arene (C4A-NH2) as a novel stationary phase for gas chromatographic (GC) separations. The statically coated C4A-NH2 capillary column showed a high column efficiency of 4332 plates/m for a 0.25 mm ID column and medium polarity. The C4A-NH2 stationary phase exhibited an excellent separation performance both for aromatic amine isomers and a complex mixture of aliphatic analytes with a wide ranging polarity, showing distinct advantages over the commercial polysiloxane stationary phases via diversified molecular interactions covering H-bonding, π-π, van der Waals interactions and shape-fitting selectivity. The retention mechanisms of aromatic amine isomers on C4A-NH2 column were further investigated by quantum chemistry calculations. In addition, the C4A-NH2 column showed good column repeatability with relative standard deviation (RSD) values of 0.03%-0.07% for run-to-run, 0.10%-0.27% for day-to-day and 2.6%-5.7% for column-to-column, respectively, and thermal stability up to 240℃.


Assuntos
Aminas/análise , Calixarenos/química , Fenóis/química , Aminas/química , Cromatografia Gasosa/métodos , Isomerismo , Reprodutibilidade dos Testes , Siloxanas/química
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