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1.
J Virol ; 94(2)2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31619563

RESUMO

Internal ribosome entry site (IRES)-driven translation is a common strategy among positive-sense, single-stranded RNA viruses for bypassing the host cell requirement of a 5' cap structure. In the current study, we identified the ribosomal protein L13 (RPL13) as a critical regulator of IRES-driven translation of foot-and-mouth disease virus (FMDV) but found that it is not essential for cellular global translation. RPL13 is also a determinant for translation and infection of Seneca Valley virus (SVV) and classical swine fever virus (CSFV), and this suggests that its function may also be conserved in unrelated IRES-containing viruses. We further showed that depletion of DEAD box helicase DDX3 disrupts binding of RPL13 to the FMDV IRES, whereas the reduction in RPL13 expression impairs the ability of DDX3 to promote IRES-driven translation directly. DDX3 cooperates with RPL13 to support the assembly of 80S ribosomes for optimal translation initiation of viral mRNA. Finally, we demonstrated that DDX3 affects the recruitment of the eukaryotic initiation factor eIF3 subunits e and j to the viral IRES. This work provides the first connection between DDX3 and eIF3e/j and recognition of the role of RPL13 in modulating viral IRES-dependent translation. This previously uncharacterized process may be involved in selective mRNA translation.IMPORTANCE Accumulating evidence has unveiled the roles of ribosomal proteins (RPs) belonging to the large 60S subunit in regulating selective translation of specific mRNAs. The translation specificity of the large-subunit RPs in this process is thought provoking, given the role they play canonically in catalyzing peptide bond formation. Here, we have identified the ribosomal protein L13 (RPL13) as a critical regulator of IRES-driven translation during FMDV infection. Our study supports a model whereby the FMDV IRESs recruit helicase DDX3 recognizing RPL13 to facilitate IRES-driven translation, with the assistance of eIF3e and eIF3j. A better understanding of these specific interactions surrounding IRES-mediated translation initiation could have important implications for the selective translation of viral mRNA and thus for the development of effective prevention of viral infection.


Assuntos
RNA Helicases DEAD-box/metabolismo , Vírus da Febre Aftosa/metabolismo , Sítios Internos de Entrada Ribossomal , Iniciação Traducional da Cadeia Peptídica , Proteínas Ribossômicas/metabolismo , Proteínas Virais/biossíntese , Animais , Chlorocebus aethiops , Cricetinae , RNA Helicases DEAD-box/genética , Fator de Iniciação 3 em Eucariotos/genética , Fator de Iniciação 3 em Eucariotos/metabolismo , Vírus da Febre Aftosa/genética , Proteínas Ribossômicas/genética , Ribossomos/genética , Ribossomos/metabolismo , Suínos , Células Vero , Proteínas Virais/genética
2.
J Am Chem Soc ; 140(33): 10435-10438, 2018 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30084632

RESUMO

Conjugating a hydrophilic and protein-resistant polymer to a protein is a widely used strategy to extend the in vivo half-life of the protein; however, the benefit of the half-life extension is usually limited by the bioactivity decrease. Herein we report a supramolecular self-assembly strategy of site-specific in situ polymerization induced self-assembly (SI-PISA) to address the dilemma. An amphiphilic block copolymer (POEGMA-PHPMA) was directly grown from the C-terminus of an important therapeutic protein interferon-α (IFN) to in situ form IFN-POEGMA-PHPMA conjugate micelles. Notably, the in vitro bioactivity of the micelles was 21.5-fold higher than that of the FDA-approved PEGylated interferon-α PEGASYS. Particularly, the in vivo half-life of the micelles (83.8 h) was 1.7- and 100-fold longer than those of PEGASYS (49.5 h) and IFN (0.8 h), respectively. In a tumor-bearing mouse model, the micelles completely suppressed tumor growth with 100% animal survival, whereas at the same dose, PEGASYS and IFN were much less effective. These findings suggest that SI-PISA is promising as a next-generation technology to remarkably enhance the pharmacological performance of therapeutic proteins with short circulation half-lives.


Assuntos
Interferon-alfa/química , Micelas , Polietilenoglicóis/química , Polimerização , Ácidos Polimetacrílicos/química , Animais , Xenoenxertos , Camundongos , Proteínas Recombinantes/química
3.
Biomacromolecules ; 19(11): 4472-4479, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30351917

RESUMO

Self-assembly of site-selective protein-polymer conjugates into stimuli-responsive micelles is interesting owing to their potential biomedical applications, ranging from molecular imaging to drug delivery, but remains a significant challenge. Herein we report a method of site-selective in situ growth-induced self-assembly (SIGS) to synthesize site-specific human serum albumin-poly(2-(diisopropylamino)ethyl methacrylate) (HSA-PDPA) conjugates that can in situ self-assemble into pH-responsive micelles with tunable morphologies. Indocyanine green (ICG) was selectively loaded into the core of sphere-like HSA-PDPA micelles to form pH-responsive fluorescence nanoprobes. The nanoprobes rapidly dissociated into protonated individual unimers at a transition pH of around 6.5, that is the extracellular pH of tumors, which resulted in a sharp fluorescence increase and markedly enhanced cellular uptake. In a tumor-bearing mouse model, they exhibited greatly enhanced tumor fluorescence imaging as compared to ICG alone and pH-nonresponsive nanoprobes. These findings suggest that pH-responsive and site-selective protein-polymer conjugate micelles synthesized by SIGS are promising as a new class of tumor microenvironment-responsive nanocarriers for enhanced tumor imaging and therapy.


Assuntos
Fluorescência , Melanoma/patologia , Metilmetacrilatos/química , Imagem Molecular/métodos , Polímeros/química , Albumina Sérica Humana/química , Microambiente Tumoral , Animais , Feminino , Humanos , Concentração de Íons de Hidrogênio , Processamento de Imagem Assistida por Computador , Verde de Indocianina , Melanoma/diagnóstico por imagem , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Espectroscopia de Luz Próxima ao Infravermelho , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Drug Deliv Transl Res ; 14(9): 2386-2402, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38236508

RESUMO

During the development of hepatocellular carcinoma (HCC), hepatic stellate cells undergo activation and transform into cancer-associated fibroblasts (CAFs) due to the influence of tumor cells. The interaction between CAFs and tumor cells can compromise the effectiveness of chemotherapy drugs and promote tumor proliferation, invasion, and metastasis. This study explores the potential of glycyrrhetinic acid (GA)-modified liposomes (lip-GA) as a strategy for co-delivery of berberine (Ber) and doxorubicin (Dox) to treat HCC. The characterizations of liposomes, including particle size, zeta potential, polydispersity index, stability and in vitro drug release, were investigated. The study evaluated the anti-proliferation and anti-migration effects of Dox&Ber@lip-GA on the Huh-7 + LX-2 cell model were through MTT and wound-healing assays. Additionally, the in vivo drug distribution and anti-tumor efficacy were investigated using the H22 + NIH-3T3-bearing mouse model. The results indicated that Dox&Ber@lip-GA exhibited a nanoscale particle size, accumulated specifically in the tumor region, and was efficiently taken up by tumor cells. Compared to other groups, Dox&Ber@lip-GA demonstrated higher cytotoxicity and lower migration rates. Additionally, it significantly reduced the deposition of extracellular matrix (ECM) and inhibited tumor angiogenesis, thereby suppressing tumor growth. In conclusion, Dox&Ber@lip-GA exhibited superior anti-tumor effects both in vitro and in vivo, highlighting its potential as an effective therapeutic strategy for combating HCC.


Assuntos
Berberina , Carcinoma Hepatocelular , Movimento Celular , Proliferação de Células , Doxorrubicina , Ácido Glicirretínico , Lipossomos , Neoplasias Hepáticas , Berberina/administração & dosagem , Berberina/farmacocinética , Berberina/química , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Doxorrubicina/química , Doxorrubicina/farmacologia , Ácido Glicirretínico/administração & dosagem , Ácido Glicirretínico/química , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Humanos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células NIH 3T3 , Liberação Controlada de Fármacos , Tamanho da Partícula , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/química , Sistemas de Liberação de Medicamentos
5.
Macromol Rapid Commun ; 34(7): 616-20, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-23401022

RESUMO

A polyvinylpyrrolidone (PVP)-based fluorescent film with stable optical properties is successfully prepared in one pot without any additive. The reaction mechanism of ring-opening and self-crosslinking of linear PVP is proposed and demonstrated. The morphologies and the nanostructures of the fluorescent film as well as the unmodified film are investigated. The dye is incorporated into the film networks via covalent linkages, thus leading to the highly stable optical properties. The facile and effective synthesis approach opens a new way for the design of other multi-functional composite materials based on linear PVP.


Assuntos
Corantes Fluorescentes/química , Nanoestruturas/química , Povidona/química , Estrutura Molecular , Povidona/síntese química , Propriedades de Superfície
6.
Biosens Bioelectron ; 222: 114996, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36521203

RESUMO

Here, a novel and portable machine learning-assisted smartphone-based visual molecularly imprinted ratiometric electrochemiluminescence (MIRECL) sensing platform was constructed for highly selective sensitive detection of 2,4-Dichlorophenoxyacetic acid (2,4-D) for the first time. Te doped CdS-coated Mn3O4 (Te-CdS@Mn3O4) with catalase-like activity served as cathode-emitter, while luminol as anode luminophore accompanied H2O2 as co-reactant, and Te-CdS@Mn3O4 decorated molecularly imprinted polymers (MIPs) as recognition unit, respectively. Molecular models were constructed and MIP band and binding energies were calculated to elucidate the luminescence mechanism and select the best functional monomers. The peroxidase activity and the large specific surface area of Mn3O4 and the electrochemical effect can significantly improve the ECL intensity and analytical sensitivity of Te-CdS@Mn3O4. 2,4-D-MIPs were fabricated by in-situ electrochemical polymerization, and the rebinding of 2,4-D inhibits the binding of H2O2 to the anode emitter, and with the increase of the cathode impedance, the ECL response of Te-CdS@Mn3O4 decreases significantly. However, the blocked reaction of luminol on the anode surface also reduces the ECL response. Thus, a double-reduced MIRECL sensing system was designed and exhibited remarkable performance in sensitivity and selectivity due to the specific recognition of MIPs and the inherent ratio correction effect. Wider linear range in the range of 1 nM-100 µM with a detection limit of 0.63 nM for 2,4-D detection. Interestingly, a portable and visual smartphone-based MIRECL analysis system was established based on the capture of luminescence images by smartphones, classification and recognition by convolutional neural networks, and color analysis by self-developed software. Therefore, the developed MIRECL sensor is suitable for integration with portable devices for intelligent, convenient, and fast detection of 2,4-D in real samples.


Assuntos
Técnicas Biossensoriais , Impressão Molecular , Impressão Molecular/métodos , Smartphone , Luminol/química , Peróxido de Hidrogênio , Medições Luminescentes/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção , Polímeros Molecularmente Impressos , Ácido 2,4-Diclorofenoxiacético , Técnicas Eletroquímicas/métodos
7.
J Hazard Mater ; 435: 128962, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35472546

RESUMO

The global occurrence of plastic fragment pollutants in water resources has raised concerns about food safety, drinking water security, and long-term ecological impacts worldwide. The different chemical nature, the persistence, and the smaller size make micro-plastics accumulators for toxins that pose a potential threat to human health. Generally, the smaller the size of the plastic fragments is, the more difficult it is to remove them from the aquatic environment. Methods to remove plastics from water or other media are highly needed. Here, we develop core-shell superparamagnetic melanin nanoparticles, which can put magnetism on nano-/micro-plastics within 30 s and then rapidly remove them from water by applying an external magnetic field. The shell material (artificial nano-melanin) provides simultaneously attractive electrostatic, hydrophobic interaction, and van der Waals' forces to attract nano-/micro-plastics, which plays a key role in the rapid remediation of the plastic fragments. With this principle applied to a simple method, the average removal efficiency achieves 89.3%. We show a method for high-throughput remediation of various micro-plastics with simple materials and processes, which have the potential for rapid, green, and large-scale remediation in the future.


Assuntos
Água Potável , Poluentes Químicos da Água , Humanos , Concentração de Íons de Hidrogênio , Fenômenos Magnéticos , Melaninas , Microplásticos , Plásticos/química , Poluentes Químicos da Água/análise
8.
Biosens Bioelectron ; 209: 114262, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35429772

RESUMO

A novel, portable, and smartphone-based molecularly imprinted polymer electrochemiluminescence (MIP-ECL) sensing platform was constructed for sensitive and selective determination of furosemide (FSM). In this platform, MoSe2 nanoparticles/starch-derived biomass carbon (MoSe2/BC) nanocomposites as imprinted material, lucigenin (Luc) as the energy donor, CdS quantum dots (CdS QDs) were used as the luminophore (energy acceptor), and molecularly imprinted polymer (MIP) as the specificity recognition element to construct a MIP-ECL sensing system based on electroluminescence resonance energy transfer (ECL-RET) mechanism, which enhanced the sensitivity and the specificity of this system. Imprinted materials were characterized by SEM, TEM, XRD, FT-IR, etc. and the recognition performance of MIP was characterized using CV, EIS, and ECL methods. The elution and re-sorption of template molecules can be used as a switch to control ECL based on the signal that can be quenched by FSM. Interestingly, deep learning based on convolutional neural networks realizes batch processing of ECL signals. Additionally, this developed MIP-ECL method was established by using the traditional ECL analyzer detector for the assay of FSM with a detection limit of 4 nM in the range of 0.010 µM-100 µM. Besides, the consumer smartphone sensing platform based on deep learning showed an outstanding linear response between the R-value of the picture and the concentration of furosemide in the range of 1-70 µM with a detection limit of 0.25 µΜ, which is much lower than that the reported for other detection methods. More importantly, due to the transferability of deep learning, the smartphone-based MIP-ECL systems can facilitate the real-time monitoring of biochemical analytes in multiple fields.


Assuntos
Técnicas Biossensoriais , Aprendizado Profundo , Impressão Molecular , Pontos Quânticos , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Furosemida , Limite de Detecção , Medições Luminescentes/métodos , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Pontos Quânticos/química , Smartphone , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Ethnopharmacol ; 265: 113115, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32891812

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ancient Egyptian texts only offer glimpses into their conceptual understandings of the inner-body and illness manifestation. Explanations of how prescribed materia medica were believed to work are rare and obscure, often resulting in modern approximations for ancient terminology such as 'ra-ib'-an ancient Egyptian classification predominantly translated as 'stomach'-leading to misunderstandings of historical texts, and therefore their use of pharmacology. AIM OF THE STUDY: To investigate the ra-ib and the explanatory models of illness from the Egyptian perspective, and to explore the link between these and the prescribed selection of materia medica. To then compare the conceptual mechanics of these treatment strategies with those of another non-Western tradition-namely Traditional Chinese Medicine (TCM)-to provide further insight into potential conceptual frameworks. MATERIALS AND METHODS: We conducted a case study of a unit of Ancient Egyptian texts focusing on the ra-ib. Totalling 34 prescriptions, the first stage lexicographically analysed the texts using cognitive linguistic and translation theories to produce our new understanding. This enabled our comparison of the mechanics of materia medica usage within these texts with those found in TCM outlined by the Pharmacopoeia of the Peoples Republic of Pharmacopeia of the People's Republic of China 2015 for the relevant ingredients. RESULTS: the study demonstrated that-rather than denoting the organ 'stomach'-ra-ib instead constitutes a system running from the mouth, downward to the anus. This is best translated as 'inner thoroughfare', and changes the way in which we attempt to understand potential motivations in the selection of ingredients. By exploring common themes in the use of eleven securely translated ingredients from the Egyptian corpus and the Pharmacopoeia of the People's Republic of China-representing a modern traditional system which understands the body via a series of interconnected systems-we were able to highlight certain themes which might be 'universal' to system-based traditions; this provided new insights into the Egyptian motivations for treatment selection. CONCLUSIONS: Having gained the ancient view of the body and illness, cultural comparisons are important for providing further potential insights and clarifications of a discontinued historical healing tradition. The new understanding of the ra-ib from our study greatly changes the way in which we understand the dynamics of Egyptian ethnopharmacological source material from this period.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Materia Medica/história , Medicina Tradicional Chinesa/métodos , Antigo Egito , Etnofarmacologia , História Antiga , Humanos , Materia Medica/farmacologia , Farmacopeias como Assunto
10.
Nanoscale ; 8(9): 5302-12, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26881415

RESUMO

A novel smart fluorescent drug delivery system composed of a perylene diimide (PDI) core and block copolymer poly(d,l-lactide)-b-poly(ethyl ethylene phosphate) is developed and named as PDI-star-(PLA-b-PEEP)8. The biodegradable PDI-star-(PLA-b-PEEP)8 is a unimolecular micelle and can self-assemble into supramolecular micelles, called as fluorescent supramolecular micelles (FSMs), in aqueous media. An insoluble drug camptothecin (CPT) can be effectively loaded into the FSMs and exhibits pH-responsive release. Moreover, the FSMs with good biocompatibility can also be employed as a remarkable fluorescent probe for cell labelling because the maximum emission of PDI is beneficial for bio-imaging. The flow cytometry and confocal laser scanning microscopy analysis demonstrate that the micelles are easily endocytosed by cancer cells. In vitro and in vivo tumor growth-inhibitory studies reveal a better therapeutic effect of FSMs after CPT encapsulation when compared with the free CPT drug. The multifunctional FSM nanomedicine platform as a nanovehicle has great potential for fluorescence imaging-guided cancer therapy.


Assuntos
Corantes Fluorescentes , Micelas , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/terapia , Imagem Óptica/métodos , Animais , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Humanos , Imidas/química , Imidas/farmacologia , Camundongos Endogâmicos BALB C , Nanomedicina , Perileno/análogos & derivados , Perileno/química , Perileno/farmacologia , Poliésteres/química , Poliésteres/farmacologia
11.
Nanoscale ; 8(8): 4452-7, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26847879

RESUMO

The challenge in photothermal therapy (PTT) is to develop biocompatible photothermal transducers that can absorb and convert near-infrared (NIR) light into heat with high efficiency. Herein, we report salt-induced aggregation of gold nanoparticles (GNPs) in biological media to form highly efficient and biocompatible NIR photothermal transducers for PTT and photothermal/photoacoustic (PT/PA) imaging of cancer. The GNP depots in situ formed by salt-induced aggregation of GNPs show strong NIR absorption induced by plasmonic coupling between adjacent GNPs and very high photothermal conversion efficiency (52%), enabling photothermal destruction of tumor cells. More interestingly, GNPs in situ aggregate in tumors to form GNP depots, enabling simultaneous PT/PA imaging and PTT of the tumors. These findings may provide a simple and effective way to develop a new class of intelligent and biocompatible NIR photothermal transducers with high efficiency for PT/PA imaging and PTT.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Cloreto de Sódio/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Difusão Dinâmica da Luz , Humanos , Raios Infravermelhos , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/toxicidade , Camundongos , Camundongos Nus , Microscopia Eletrônica de Transmissão , Neoplasias/diagnóstico por imagem , Neoplasias/mortalidade , Neoplasias/terapia , Técnicas Fotoacústicas , Fototerapia , Polietilenoglicóis/química , Taxa de Sobrevida , Transplante Heterólogo
12.
Biomaterials ; 47: 13-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25682156

RESUMO

A major disadvantage of therapeutic proteins is their instability to external stressors during storage, transport and use. Here, we report site-specific in situ growth of a cyclized protein-polymer conjugate with improved in vitro and in vivo stability. Green fluorescence protein (GFP) was genetically fused at its N- and C-termini with two sortase recognition sequences pentaglycine and LPETG, respectively to yield a linear GFP (l-GFP). A cyclized GFP (c-GFP) was generated from the l-GFP by sortase-catalyzed cyclization. A maleimide-functionalized atom transfer radical polymerization (ATRP) initiator was selectively attached to a free cysteine residue genetically engineered at the C-terminus of GFP to form a macroinitiator (c-GFP-Br). Subsequent in situ ATRP of oligo(ethylene glycol) methyl ether methacrylate (OEGMA) from the c-GFP-Br generated a site-specific (C-terminal) and stoichiometric (1:1) c-GFP-POEGMA conjugate with almost quantitative conversion and highly retained activity. Notably, the c-GFP-POEGMA conjugate showed 9- and 310-fold increases in thermal stability as compared to the l-GFP and its counterpart l-GFP-POEGMA, respectively. Additionally, the conjugate displayed significantly improved tumor retention relative to the l-GFP and l-GFP-POEGMA. The method developed may be applicable to a variety of therapeutic proteins to improve their in vitro and in vivo stability.


Assuntos
Materiais Biocompatíveis/química , Proteínas de Fluorescência Verde/química , Polímeros/química , Engenharia de Proteínas , Proteínas/química , Aminoaciltransferases/química , Animais , Proteínas de Bactérias/química , Compostos de Benzil/química , Linhagem Celular Tumoral , Cromatografia Líquida , Dicroísmo Circular , Cisteína Endopeptidases/química , Eletroforese em Gel de Poliacrilamida , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Ligação Proteica , Estrutura Terciária de Proteína , Piridazinas/química , Quinolinas/química , Espectrometria de Fluorescência , Espectrometria de Massas em Tandem
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