Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.064
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Chemistry ; 26(2): 384-389, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31550056

RESUMO

Phosphatidylinositol (PI) is the biosynthetic precursor for seven phosphoinositides, important signaling lipids in cells. A membrane-permeant caged PI derivative featuring a photo-removable coumarinyl group masking the negative charge of the phosphate, as well as two enzymatically removable butyrate esters for increased lipophilicity and for preventing phosphate migration, were synthesized. Rapid cell entry and cellular labeling in fixed cells was demonstrated by a photo-cross-linkable diazirine followed by attachment of a fluorophore through click chemistry. Using this technique, we found that the multifunctional caged PI derivative resided predominantly at internal membranes but rapidly changed to the plasma membrane after uncaging. Accordingly, a preliminary proteomic analysis of the lipid-protein conjugates revealed that the two major PI transport proteins PITPα and ß were prime targets of the photo-cross-linked PI derivative.


Assuntos
Fosfatidilinositóis/química , Coloração e Rotulagem/métodos , Membrana Celular/metabolismo , Química Click , Células HeLa , Humanos , Microscopia de Fluorescência , Fosfatidilinositóis/síntese química , Fosfatidilinositóis/metabolismo
2.
J Chromatogr A ; 1609: 460446, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31420178

RESUMO

Two new copolymer-grafted silica stationary phases were prepared and employed in hydrophilic interaction chromatography (HILIC). 2-(Dimethylamino)ethyl methacrylate (DMAEMA) are copolymerized with itaconic acid (IA) and acrylic acid (AA) respectively, via thiol-ene click reaction on silica surface with deep eutectic solvents (DES) as new solvents. The obtained poly(DMAEMA-co-itaconic acid)-grafted silica (Sil-PDM-PIA) and poly(DMAEMA-co-acrylic acid)-grafted silica (Sil-PDM-PAA) were characterized by Fourier transform infrared spectroscopy, elemental analysis and solid-state 13C NMR spectra. Their hydrophilic interaction performances were evaluated by separating nucleosides, nucleobases, saccharides, and amino acids. Compared with previous reported poly(itaconic acid)-grafted silica (Sil-PIA) and poly(acrylic acid)-grafted silica (Sil-PAA) stationary phases, these two new copolymer-grafted silica performed higher selectivity and better separation for polar analytes in HILIC.


Assuntos
Cromatografia/métodos , Química Click/métodos , Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Dióxido de Silício/química , Solventes/química , Compostos de Sulfidrila/química , Acetonitrilos/química , Aminoácidos/isolamento & purificação , Entropia , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Metacrilatos/química , Nucleosídeos/isolamento & purificação , Nylons/química , Reprodutibilidade dos Testes , Sais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Succinatos/química , Temperatura Ambiente
3.
Chemistry ; 26(8): 1800-1810, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31692134

RESUMO

Nature relies on reading and synthesizing the genetic code with high fidelity. Nucleic acid building blocks that are orthogonal to the canonical A-T and G-C base-pairs are therefore uniquely suitable to facilitate position-specific labeling of nucleic acids. Here, we employ the orthogonal kappa-xanthosine-base-pair for in vitro transcription of labeled RNA. We devised an improved synthetic route to obtain the phosphoramidite of the deoxy-version of the kappa nucleoside in solid phase synthesis. From this DNA template, we demonstrate the reliable incorporation of xanthosine during in vitro transcription. Using NMR spectroscopy, we show that xanthosine introduces only minor structural changes in an RNA helix. We furthermore synthesized a clickable 7-deaza-xanthosine, which allows to site-specifically modify transcribed RNA molecules with fluorophores or other labels.


Assuntos
RNA/química , Ribonucleosídeos/química , Pareamento de Bases , Química Click , Código Genético , Ressonância Magnética Nuclear Biomolecular , Conformação de Ácido Nucleico , RNA/metabolismo , Ribonucleosídeos/metabolismo , Técnicas de Síntese em Fase Sólida
4.
Chempluschem ; 84(7): 775-778, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31681526

RESUMO

In the past decade, several developments have expanded the chemical toolbox for astatination and the preparation of 211At-labeled radiopharmaceuticals. However, there is still a need for advanced methods for the synthesis of astatinated (bio)molecules to address challenges such as limited in vivo stability. Herein, we report the development of multifunctional 211At-labeled reagents that can be prepared by applying a modular and versatile click approach for rapid assembly. The introduction of tetrazines as bioorthogonal tags enables rapid radiolabeling and radio-crosslinking, which is demonstrated by steric shielding of 211At to significantly increase label stability in human blood plasma.


Assuntos
Química Click/métodos , Compostos Radiofarmacêuticos/química , Astato/química , Meia-Vida , Compostos Heterocíclicos com 1 Anel/química , Humanos , Marcação por Isótopo , Compostos Radiofarmacêuticos/sangue , Compostos Radiofarmacêuticos/síntese química
5.
Chem Commun (Camb) ; 55(96): 14506-14509, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31735949

RESUMO

Polymers are an attractive anchoring platform for the synthesis of radioimmunoconjugates. They enable independent control over the amount of radioisotope loading and antibody attachment, which is pivotal in developing tailorable formulations for personalised medicine. Herein, we report the synthesis of p(HEMA-ran-GMA) for the conjugation of lutetium ions and rituximab as a functional platform for radioimmunotherapy. We demonstrate the suitability of this platform using non-Hodgkin's lymphoma cells.


Assuntos
Imunoconjugados/química , Linfoma não Hodgkin/radioterapia , Radioimunoterapia , Antineoplásicos Imunológicos/química , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Química Click , Compostos de Epóxi/química , Humanos , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico , Lutécio/química , Metacrilatos/química , Polímeros/química , Rituximab/química , Rituximab/farmacologia , Rituximab/uso terapêutico
6.
Chem Commun (Camb) ; 55(87): 13093-13095, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31612161

RESUMO

Ubiquitin monomers functionalized with an azide or multiple alkynes were utilized for the assembly of branched ubiquitin oligomers (K6/K11, K11/K48, K11/K63, K6/K11/K48) by click chemistry. The oligomers resist deubiquitylase-catalysed hydrolysis and exhibit stability in eukaryotic cell lysates.


Assuntos
Ubiquitina/biossíntese , Alquinos/química , Azidas/química , Biocatálise , Química Click , Enzimas Desubiquitinantes/metabolismo , Células Eucarióticas/metabolismo , Humanos , Hidrólise , Ubiquitina/química , Ubiquitina/metabolismo , Ubiquitinação
7.
Molecules ; 24(19)2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581645

RESUMO

In recent years, several catalyst-free site-specific reactions have been investigated for the efficient conjugation of biomolecules, nanomaterials, and living cells. Representative functional group pairs for these reactions include the following: (1) azide and cyclooctyne for strain-promoted cycloaddition reaction, (2) tetrazine and trans-alkene for inverse-electron-demand-Diels-Alder reaction, and (3) electrophilic heterocycles and cysteine for rapid condensation/addition reaction. Due to their excellent specificities and high reaction rates, these conjugation methods have been utilized for the labeling of radioisotopes (e.g., radiohalogens, radiometals) to various target molecules. The radiolabeled products prepared by these methods have been applied to preclinical research, such as in vivo molecular imaging, pharmacokinetic studies, and radiation therapy of cancer cells. In this review, we explain the basics of these chemical reactions and introduce their recent applications in the field of radiopharmacy and chemical biology. In addition, we discuss the significance, current challenges, and prospects of using bioorthogonal conjugation reactions.


Assuntos
Antineoplásicos/síntese química , Compostos Radiofarmacêuticos/síntese química , Animais , Antineoplásicos/química , Catálise , Química Click , Reação de Cicloadição , Cisteína/química , Humanos , Imagem Molecular , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Compostos Radiofarmacêuticos/química
9.
Chem Biodivers ; 16(11): e1900340, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31647170

RESUMO

A series of camphecene and quinolizidine alkaloid (-)-cytisine conjugates has been obtained for the first time using 'click' chemistry methodology. The cytotoxicity and virus-inhibiting activity of compounds were determined against MDCK cells and influenza virus A/Puerto Rico/8/34 (H1N1), correspondingly, in in vitro tests. Based on the results obtained, values of 50 % cytotoxic dose (CC50 ), 50 % inhibition dose (IC50 ) and selectivity index (SI) were determined for each compound. It has been shown that the antiviral activity is affected by the length and nature of linkers between cytisine and camphor units. Conjugate 13 ((1R,5S)-3-(6-{4-[(2-{(E)-[(1R,4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene]amino}ethoxy)methyl]-1H-1,2,3-triazol-1-yl}hexyl)-1,2,3,4,5,6-hexahydro-8H-1,5-methanopyrido[1,2-a][1,5]diazocin-8-one), which contains cytisine fragment separated from triazole ring by -C6 H12 - aliphatic linker, showed the highest activity at relatively low toxicity (CC50 =168 µmol, IC50 =8 µmol, SI=20). Its selectivity index appeared higher than that of reference compound, rimantadine. According to theoretical calculations, the antiviral activity of the lead compound 13 can be explained by its influence on the functioning of neuraminidase.


Assuntos
Alcaloides/farmacologia , Antivirais/farmacologia , Cânfora/análogos & derivados , Etanolaminas/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Alcaloides/química , Animais , Antivirais/síntese química , Antivirais/química , Azocinas/química , Azocinas/farmacologia , Cânfora/química , Cânfora/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Galinhas , Química Click , Relação Dose-Resposta a Droga , Etanolaminas/química , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Quinolizinas/química , Quinolizinas/farmacologia
10.
J Chem Phys ; 151(14): 144706, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615228

RESUMO

Quantum dot (QD) biological imaging and sensing applications often require surface modification with single-stranded deoxyribonucleic acid (ssDNA) oligonucleotides. Furthermore, ssDNA conjugation can be leveraged for precision QD templating via higher-order DNA nanostructures to exploit emergent behaviors in photonic applications. Use of ssDNA-QDs across these platforms requires compact, controlled conjugation that engenders QD stability over a wide pH range and in solutions of high ionic strength. However, current ssDNA-QD conjugation approaches suffer from limitations, such as the requirement for thick coatings, low control over ssDNA labeling density, requirement of large amounts of ssDNA, or low colloidal or photostability, restraining implementation in many applications. Here, we combine thin, multidentate, phytochelatin-3 (PC3) QD passivation techniques with strain-promoted copper-free alkyne-azide click chemistry to yield functional ssDNA-QDs with high stability. This process was broadly applicable across QD sizes (i.e., λem = 540, 560, 600 nm), ssDNA lengths (i.e., 10-16 base pairs, bps), and sequences (poly thymine, mixed bps). The resulting compact ssDNA-QDs displayed a fluorescence quenching efficiency of up to 89% by hybridization with complementary ssDNA-AuNPs. Furthermore, ssDNA-QDs were successfully incorporated with higher-order DNA origami nanostructure templates. Thus, this approach, combining PC3 passivation with click chemistry, generates ssDNA-PC3-QDs that enable emergent QD properties in DNA-based devices and applications.


Assuntos
DNA de Cadeia Simples/química , Nanocompostos/química , Pontos Quânticos/química , Alquinos/química , Azidas/química , Compostos de Cádmio/química , Química Click , Fluorescência , Ouro/química , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/química , Fitoquelatinas/química , Poli T/química , Compostos de Selênio/química , Sulfetos/química , Propriedades de Superfície , Compostos de Zinco/química
11.
Nat Commun ; 10(1): 4697, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619683

RESUMO

Comprehensive protein identification and concomitant structural probing of proteins are of great biological significance. However, this is challenging to accomplish simultaneously in one confined space. Here, we develop a nanosecond photochemical reaction (nsPCR)-based click chemistry, capable of structural probing of proteins and enhancing their identifications through on-demand removal of surrounding matrices within nanoseconds. The nsPCR is initiated using a photoactive compound, 2-nitrobenzaldehyde (NBA), and is examined by matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS). Benefiting from the on-demand matrix-removal effect, this nsPCR strategy enables enhanced neuropeptide identification and visualization from complex tissue samples such as mouse brain tissue. The design shows great promise for structural probing of proteins up to 155 kDa due to the exclusive accessibility of nsPCR to primary amine groups, as demonstrated by its general applicability using a series of proteins with various lysine residues from multiple sample sources, with accumulated labeling efficiencies greater than 90%.


Assuntos
Encéfalo/metabolismo , Química Click , Neuropeptídeos/metabolismo , Processos Fotoquímicos , Coloração e Rotulagem , Animais , Benzaldeídos , Braquiúros , Camundongos , Imagem Óptica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Chemistry ; 25(68): 15508-15515, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31613028

RESUMO

We have developed a fully synthetic and multifunctional antibody-recruiting molecule (ARM) to guide natural antibodies already present in the blood stream against cancer cells without pre-immunization. Our ARM is composed of antibody and tumor binding modules (i.e., ABM and TBM) displaying clustered rhamnose and cyclo-RGD, respectively. By using a stepwise approach, we have first demonstrated the importance of multivalency for efficient recognition with naturel IgM and αv ß3 integrin expressing M21 tumor cell line. Once covalently conjugated by click chemistry, we confirmed by flow cytometry and confocal microscopy that the recognition properties of both the ABM and TBM are conserved, and more importantly, that the resulting ARM promotes the formation of a ternary complex between natural IgM and cancer cells, which is required for the stimulation of the cytotoxic immune response in vivo. Due to the efficiency of the synthetic process, a larger diversity of heterovalent ligands could be easily explored by using the same multivalent approach and could open new perspectives in this field.


Assuntos
Anticorpos/imunologia , Glicoconjugados/química , Integrina alfaVbeta3/metabolismo , Ramnose/química , Linhagem Celular Tumoral , Química Click , Citometria de Fluxo , Humanos , Imunização , Integrina alfaVbeta3/química , Ligantes
13.
Org Biomol Chem ; 17(45): 9712-9725, 2019 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-31531484

RESUMO

Fluorescent hybridization probes are important tools for rapid, specific and sensitive analysis of genetic mutations. In this work, we synthesized novel alkyne-modified styryl dyes for conjugation with pyrrolidinyl peptide nucleic acid (acpcPNA) by click chemistry for the development of hybridization responsive fluorescent PNA probes. The free styryl dyes generally exhibited weak fluorescence in aqueous media, and the fluorescence was significantly enhanced (up to 125-fold) upon binding with DNA duplexes. Selected styryl dyes that showed good responses with DNA were conjugated with PNA via sequential reductive alkylation-click chemistry. Although these probes showed little fluorescence change when hybridized to complementary DNA, significant fluorescence enhancements were observed in the presence of structural defects including mismatched, abasic and base-inserted DNA targets. The largest increase in fluorescence quantum yield (up to 14.5-fold) was achieved with DNA carrying base insertion. Although a number of probes were designed to give fluorescence response to complementary DNA targets, probes that are responsive to mutations such as single nucleotide polymorphism (SNP), base insertion/deletion and abasic site are less common. Therefore, styryl-dye-labeled acpcPNA is a unique probe that is responsive to structural defects in the duplexes that may be further applied for diagnostic purposes.


Assuntos
Sondas de DNA/química , DNA/análise , Fluorescência , Corantes Fluorescentes/química , Ácidos Nucleicos Peptídicos/química , Pirrolidinas/química , Estirenos/química , Química Click , DNA/genética , Corantes Fluorescentes/síntese química , Estrutura Molecular , Mutação , Estirenos/síntese química
14.
Chem Asian J ; 14(19): 3240-3250, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31508892

RESUMO

With the rapid development of nanoscience and nanotechnology, various types of functional nanoreactors have been designed for diverse applications. Here, the recent evolution of the rational design of nanoreactors for chemical synthesis and biomedical applications are briefly summarized and discussed. The presence of nanoreactors provides constrained space isolated from the surrounding environment. Scientists are committed to studying changes in chemical reactions when the reaction system is confined to the nanosized space. Nanoreactors accelerate the reaction rate and even change mechanism of some chemical reactions. Cells and organelles as natural nanoreactors are also discussed. The development of intracellular synthesis makes it possible to realize various applications in biomedicine. The challenges on the rational design of nanoreactors and perspectives are also discussed.


Assuntos
Nanotecnologia , Tecnologia Biomédica , Técnicas Biossensoriais/métodos , Química Click , Nanopartículas/química , Polímeros
15.
Eur J Pharm Sci ; 139: 105066, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31513922

RESUMO

Thrombomodulin (TM) is an endothelial cell membrane protein that plays essential roles in controlling vascular haemostatic balance. The 4, 5, 6 EGF-like domain of TM (TM456) has cofactor activity for thrombin binding and subsequently protein C activation. Therefore, recombinant TM456 is a promising anticoagulant candidate but has a very short half-life. Ligation of poly (ethylene glycol) to a bioactive protein (PEGylation) is a practical choice to improve stability, extend circulating life, and reduce immunogenicity of the protein. Site-specific PEGylation is preferred as it could avoid the loss of protein activity resulting from nonspecific modification. We report herein two site-specific PEGylation strategies, enzymatic ligation and copper-free click chemistry (CFCC), for rTM456 modification. Recombinant TM456 with a C-terminal LPETG tag (rTM456-LPETG) was expressed in Escherichia coli for its end-point modification with NH2-diglycine-PEG5000-OMe via Sortase A-mediated ligation (SML). Similarly, an azide functionality was easily introduced at the C-terminus of rTM456-LPETG via SML with NH2-diglycine-PEG3-azide, which facilitates a site-specific PEGylation of rTM456via CFCC. Both PEGylated rTM456 conjugates retained protein C activation activity as that of rTM456. Also, they were more stable than rTM456 in Trypsin digestion assay. Further, both PEGylated rTM456 conjugates showed a concentration-dependent prolongation of thrombin clotting time (TCT) compared to non-modified protein, which confirms the effectiveness of these two site-specific PEGylation schemes.


Assuntos
Anticoagulantes/administração & dosagem , Anticoagulantes/química , Trombomodulina/administração & dosagem , Trombomodulina/química , Azidas/administração & dosagem , Azidas/química , Coagulação Sanguínea/efeitos dos fármacos , Química Click , Estabilidade de Medicamentos , Humanos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Trombina/metabolismo , Trombomodulina/genética
16.
Eur J Med Chem ; 183: 111696, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541869

RESUMO

Cell division cycle 25 (Cdc25) protein phosphatases play key roles in the transition between the cell cycle phases and their association with various cancers has been widely proven, which makes them ideal targets for anti-cancer treatment. Though several Cdc25 inhibitors have been developed, most of them displayed low activity and poor subtype selectivity. Therefore, it is extremely important to discover novel small molecule inhibitors with potent activities and significant selectivity for Cdc25 subtypes, not only served as drugs to treat cancer but also to probe its mechanism in transitions. In this study, miniaturized parallel click chemistry synthesis via CuAAC reaction followed by in situ biological screening were used to discover selective Cdc25 inhibitors. The bioassay results showed that compound M2N12 proved to be the most potent Cdc25 inhibitor, which also act as a highly selective Cdc25C inhibitor and was about 9-fold potent than that of NSC 663284. Moreover, M2N12 showed remarkable anti-growth activity against the KB-VIN cell line, equivalent to that of PXL and NSC 663284. An all-atom molecular dynamics (MD) simulation approach was further employed to probe the significant selectivity of M2N12 for Cdc25C relative to its structural homologs Cdc25A and Cdc25B. Overall, above results make M2N12 a promising lead compound for further investigation and structural modification.


Assuntos
Antineoplásicos/farmacologia , Técnicas de Química Combinatória , Inibidores Enzimáticos/farmacologia , Fosfatases cdc25/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Química Click , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Simulação de Dinâmica Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Fosfatases cdc25/metabolismo
17.
Carbohydr Res ; 484: 107780, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31479870

RESUMO

This work combined three classes of compounds in the same molecule "amino triazole-glycoside" and developed a convenient method for the synthesis of this type of compound via a one-pot two step reaction. Alkylation of amine derivatives with propargyl bromide to give propargylamine was performed in the first step subsequently followed by a 'click' reaction with various ß-azido-glycosides in the presence of CuI in aqueous solution to provide ß-amino triazole-glycosides. Thirty-two examples of glycosides were obtained in moderate to good yield using this one-pot procedure.


Assuntos
Química Click/métodos , Glicosídeos/síntese química , Alquilação , Aminas/química , Sequência de Carboidratos , Glicosídeos/química , Pargilina/análogos & derivados , Pargilina/química , Propilaminas/química , Triazóis/química
18.
Anal Bioanal Chem ; 411(25): 6745-6754, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31482291

RESUMO

In the literature, there are reports of the utilization of various hydrogels to create generic platforms for protein microarray applications. Here, a novel strategy was developed to obtain high-performance microarrays. In it, a dextran hydrogel is used to covalently immobilize oligonucleotides and proteins. This method employs aqueous solutions of dextran methacrylate (Dx-MA), which is a biocompatible photopolymerizable monomer. Capture probes are immobilized inside the hydrogel via a light-induced thiol-acrylate coupling reaction at the same time as the dextran polymer is formed. Hydrogel microarrays based on this technique were prepared on different surfaces, such as a Blu-ray Disk and polycarbonate or alkene-functionalized glass slides, and these systems showed high probe-loading capabilities and good biorecognition yields. This methodology presents advantages such as a low cost, a short analysis time, a low limit of detection, and multiplexing capabilities, among others. Confocal fluorescence microscopy analysis demonstrated that in these hydrogel-based microarrays, receptor immobilization and the biorecognition event occurred within the hydrogel and not merely on the surface.


Assuntos
Dextranos/química , Ácidos Nucleicos Imobilizados/química , Metacrilatos/química , Química Click/métodos , Hidrogéis/química , Ácidos Nucleicos/análise , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Cimento de Policarboxilato/química , Compostos de Sulfidrila/química
19.
Carbohydr Polym ; 224: 115163, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472828

RESUMO

Efficient procedure for preparation of the novel magnetic nanobiocomposite (MNbC) was successfully established by employing click chemistry protocol. The resulted structure exhibited valuable characteristics from biological viewpoints. The prepared materials and obtained nanobiocomposite were characterized by means of nuclear magnetic resonance (NMR), fourier transform infrared (FT-IR), thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). To assay the antiproliferative effects of the MNbC; as cancerous cells, Hela, MCF-7 and Saos were evaluated by means of MTT assay and compared with normal fibroblast cell line. Promising antiproliferative effects were observed on both epitheloid and mesenchymal cancer cell lines depending on MNbC concentration and time. To detect the apoptosis-associated changes of cell membranes during the process of apoptosis, Acridine Orange/Ethidium Bromide (AO/EB) dual staining fluorescent technique was incorporated. The studies in this article including all of these specifications represent convincing key findings that make MNbC as an appreciable candidate for further bio-applications.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Quitosana/química , Quitosana/farmacologia , Imãs/química , Nanocompostos/química , Química Click , Células HeLa , Humanos , Células MCF-7
20.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1864(12): 158516, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31473345

RESUMO

In the metabolism of pulmonary surfactant, the ATP-binding cassette sub-family A member 3 (ABCA3) is a crucial protein in the formation of the storage compartment for surfactant, the lamellar body (LB), and the transport of phospholipids in it. Mutations in ABCA3 not only disturb surfactant metabolism but also cause chronic interstitial lung diseases. Assays for ABCA3 transport function are needed to investigate pathophysiology of the mutations and treatment options for the patients. We metabolically labeled choline (Cho) head phospholipids with the Cho analogue, propargyl-Cho. The universal incorporation of propargyl-Cho was confirmed by mass spectrometry and labeled lipids were visualized in confocal microscopy by click reaction with an azide fluorophore. After pulse-labeling propargyl-Cho labeled lipids accumulated in ABCA3+ vesicles in a time and concentration dependent manner. When treated with the choline kinase inhibitor MN58b during the first 12 h, the lipids intensity inside ABCA3+ vesicles decreased, whereas intensity was unchanged when treated after 12 h. Miltefosine, a substrate of ABCA3, decreased the incorporation of labeled lipids in ABCA3+ vesicles at all time points. The lipids intensity inside the mutated (p.N568D or p.L1580P) ABCA3+ vesicles was decreased compared to wild type, while the intensity outside of vesicles showed no difference. Propargyl-Cho can metabolically pulse-label Cho phospholipids. Visualization and quantification of fluorescence intensity of the labeled lipids inside ABCA3+ vesicles at equilibrium can specifically assess the transport function of ABCA3.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Colina/metabolismo , Fosfolipídeos/metabolismo , Transporte Biológico Ativo , Colina/análise , Química Click , Células HEK293 , Humanos , Microscopia Confocal , Fosfolipídeos/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA