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1.
Biotechnol Appl Biochem ; 71(1): 193-201, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37904286

RESUMO

In this study, an electrochemical biosensor was constructed for the detection of fibrin, specifically by a simple two-step approach, with a novel artificial enzyme (Tetrazyme) based on the DNA tetrahedral framework as signal probe. The multichannel screen-printed electrode with the activated surface cannot only remove some biological impurities, but also serve as a carrier to immobilize a large number of antigen proteins. The DNA tetrahedral nanostructure was employed to ensure the high sensitivity of the probe for biological analysis. The hemin was chimeric into the G-quadruplex to constitute the complex with peroxidase catalytic activity (hemin/G4-DNAzyme), subsequently, Tetrazyme was formed through combining of this complex and DNA tetrahedral nucleic acid framework. The artificial enzyme signal probe formed by the covalent combination of the homing peptide (Cys-Arg-Glu-Lys-Ala, CREKA), which is the aptamer of fibrin and the new artificial enzyme is fixed on the surface of the multichannel carbon electrode by CREKA-specific recognition, so as to realize the sensitive detection of fibrin. The feasibility of sensing platform was validated by cyclic voltammetry (CV) and amperometric i-t curve (IT) methods. Effects of Tetrazyme concentration, CREKA concentrations and hybridization time on the sensor were explored. Under the best optimal conditions of 0.6 µmol/L Tetrazyme, 80 µmol/L CREKA, and 2.5 h reaction time, the immunosensor had two linear detection ranges, 10-40 nmol/L, with linear regression equation Y = 0.01487X - 0.011 (R2 = 0.992), and 50-100 nmol/L, with linear regression equation Y = 0.00137X + 0.6405 (R2 = 0.998), the detection limit was 9.4 nmol/L, S/N ≥ 3. The biosensor could provide a new method with great potential for the detection of fibrin with good selectivity, stability, and reproducibility.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Hemina/química , Fibrina , Reprodutibilidade dos Testes , Limite de Detecção , Imunoensaio , DNA/química , Técnicas Eletroquímicas/métodos
2.
Biochem Genet ; 57(3): 403-420, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30600409

RESUMO

Rice tillering ability and plant height are two of the important traits determining the grain yield. A novel rice (Oryza sativa L.) mutant dhta-34 from an Indica cultivar Zhenong 34 treated by ethyl methy1 sulfonate (EMS) was investigated in this study. The dhta-34 mutant significantly revealed thrifty tillers with reduced plant height, smaller panicles and lighter grains. It also exhibited late-maturing (19.80 days later than the wild type) and withered leaf tip during the mature stage. The length of each internode was reduced compared to the wild type, belonging to the dn type (each internode of the plant stem decreased in the same ratio). The longitudinal section of dhta-34 internodes showed that the length of cells was reduced leading to the dwarfism of the mutant. The F2 population derived from a cross between dhta-34 and an Japonica cultivar Zhenongda 104 were used for gene mapping by using the map-based cloning strategy. The gene DHTA-34 was fine mapped in 183.8kb region flanked by markers 3R-7 and 3R-10. The cloning and sequencing of the target region from the mutant revealed that there was a substitution of G to A in the second exon of LOC_Os03g10620, which resulted in an amino acid substitution arginine to histidine. DHTA-34 encoded a protein of the α/ß-fold hydrolase superfamily, which could suppress the tillering ability of rice. DHTA-34 was a strong loss-of-function allele of the Arabidopsis thaliana D14 gene, which was involved in part of strigolactones (SLs) perception and signaling. Moreover, the relative expression of DHTA-34 gene in leaf was higher than that in bud, internode, root or sheath. This study revealed that DHTA-34 played an important role in inhabiting tiller development in rice and further identifying the function of D14.


Assuntos
Genes de Plantas , Lactonas/farmacologia , Mutação , Oryza/genética , Sequência de Aminoácidos , Clonagem Molecular , Metanossulfonato de Etila/farmacologia , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Homologia de Sequência de Aminoácidos , Transdução de Sinais
3.
Plant Cell Rep ; 37(6): 933-946, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29572657

RESUMO

KEY MESSAGE: A rice receptor-like kinase gene OSBBS1/OsRLCK109 was identified; this gene played vital roles in leaf senescence and the salt stress response. Early leaf senescence can cause negative effects on rice yield, but the underlying molecular regulation is not fully understood. bilateral blade senescence 1 (bbs1), an early leaf senescence mutant with a premature senescence phenotype that occurs mainly performing at the leaf margins, was isolated from a rice mutant population generated by ethylmethane sulfonate (EMS) treatment. The mutant showed premature leaf senescence beginning at the tillering stage and exhibited severe symptoms at the late grain-filling stage. bbs1 showed accelerated dark-induced leaf senescence. The OsBBS1 gene was cloned by a map-based cloning strategy, and a guanine (G) insertion was found in the first exon of LOC_Os03g24930. This gene encodes a receptor-like cytoplasmic kinase and was named OsRLCK109 in a previous study. Transgenic LOC_Os03g24930 knockout plants generated by a CRISPR/Cas9 strategy exhibited similar early leaf senescence phenotypes as did the bbs1 mutant, which confirmed that LOC_Os03g24930 was the OsBBS1 gene. OsBBS1/OsRLCK109 was expressed in all detected tissues and was predominantly expressed in the main vein region of mature leaves. The expression of OsBBS1 could be greatly induced by salt stress, and the bbs1 mutant exhibited hypersensitivity to salt stress. In conclusion, this is the first identification of OsRLCKs participating in leaf senescence and playing critical roles in the salt stress response in rice (Oryza sativa L.).


Assuntos
Guanina , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Mutagênese Insercional , Mutação , Oryza/genética , Fenótipo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Sais , Estresse Fisiológico , Fatores de Tempo
4.
Mol Genet Genomics ; 292(2): 385-395, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28012016

RESUMO

Ferredoxin-dependent glutamate synthase (Fd-GOGAT, EC 1.4.7.1) plays major roles in photorespiration and primary nitrogen assimilation. However, due to no mutant or knockdown lines of OsFd-GOGAT have been reported in rice (Oryza sativa L.), the contribution of OsFd-GOGAT to rice foliar nitrogen metabolism remains little up-to-date. Here, we isolated a rice premature leaf senescence mutant named gogat1, which was reduced in 67% of the total GOGAT enzyme activity in leaves. The gogat1 mutant exhibited chlorosis under natural condition, while showed less extent premature leaf senescence under low light treatment. The gogat1 locus was mapped to a 54.1 kb region on chromosome 7, and the sequencing of OsFd-GOGAT showed one substitution (A to T) at the 3017th nucleotide of the open reading frame, leading to the amino-acid substitution of leucine changed to histidine. The gogat1 mutant showed reduced seed setting rate, while the grain protein content in gogat1 mutant was significantly higher than that in wild type. Meanwhile, during the grain-filling stage, total amino acids in the up three leaves and the upmost internode were increased dramatically. The results in this study suggested that OsFd-GOGAT might participate in nitrogen remobilization during leaf senescence, which provides a potential way to improve nitrogen use efficiency in rice.


Assuntos
Aminoácido Oxirredutases/metabolismo , Nitrogênio/metabolismo , Oryza/genética , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Aminoácido Oxirredutases/genética , Arabidopsis/genética , Mapeamento Cromossômico , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Luz , Mutação , Oryza/enzimologia , Fenótipo , Folhas de Planta/enzimologia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo , Sementes/metabolismo
5.
Nanotechnology ; 27(25): 254003, 2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27183363

RESUMO

Diabetes mellitus (DM) is one of the most common metabolic disorders in the world, of which more than 90% is type-2 diabetes mellitus (T2DM). There is a rather urgent need for reliable, sensitive and quick detection techniques in clinical application of T2DM. Ficolin-3 is a potential biomarker of T2DM, because serum ficolin-3 levels are associated with insulin resistance and predict the incidence of T2DM. Herein, a sandwich-type electrochemical immunosensor was developed for the detection of ficolin-3 in human serum. Cyclic voltammetry and the amperometric current versus time were used to characterize the performance of the immunosensor. Under optimal conditions, the detection limitation of ficolin-3 was 100 ng ml(-1) and the linear dynamic range was between 2 and 50 µg ml(-1). The method has ideal accuracy, excellent stability and selectivity and has wide application prospects in clinical research.


Assuntos
Técnicas Eletroquímicas , Lectinas/sangue , Técnicas Biossensoriais , Ouro , Humanos , Imunoensaio , Limite de Detecção , Ficolinas
6.
Int J Biol Macromol ; 257(Pt 1): 128605, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061508

RESUMO

Co-fermentation of multiple substrates has emerged as the most effective method to improve the yield of bioproducts. Herein, sustainable rubberwood enzymatic hydrolysates (RWH) were co-fermented by Aureobasidium pullulans to produce poly(ß-L-malic acid) (PMA), and RWH + glucose/xylose was also investigated as co-substrates. Owing to low inhibitor concentration and abundant natural nitrogen source content of RWH, a high PMA yield of 0.45 g/g and a productivity of 0.32 g/L/h were obtained by RWH substrate fermentation. After optimization, PMA yields following the fermentation of RWH + glucose and RWH + xylose reached 59.92 g/L and 53.71 g/L, respectively, which were 52 % and 36 % higher than that after the fermentation of RWH. RWH + glucose more significantly affected the correlation between PMA yield and substrate concentration than RWH + xylose. The results demonstrated that the co-fermentation of RWH co-substrate is a promising method for the synthesis of bioproducts.


Assuntos
Aureobasidium , Polímeros , Xilose , Fermentação , Polímeros/metabolismo , Malatos , Glucose
7.
Cell Prolif ; 57(6): e13603, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38228366

RESUMO

Breast cancer has overtaken lung cancer as the number one cancer worldwide. Paclitaxel (PTX) is a widely used first-line anti-cancer drug, but it is not very effective in clinical breast cancer therapy. It has been reported that triptolide (TPL) can enhance the anticancer effect of paclitaxel, and better synergistic therapeutic effects are seen with concomitant administration of PTX and TPL. In this study, we developed pH-responsive polymeric micelles for co-delivery of PTX and TPL, which disassembling in acidic tumour microenvironments to target drug release and effectively kill breast cancer cells. Firstly, we synthesized amphiphilic copolymer mPEG2000-PBAE through Michael addition reaction, confirmed by various characterizations. Polymer micelles loaded with TPL and PTX (TPL/PTX-PMs) were prepared by the thin film dispersion method. The average particle size of TPL/PTX-PMs was 97.29 ± 1.63 nm, with PDI of 0.237 ± 0.003 and Zeta potential of 9.57 ± 0.80 mV, LC% was 6.19 ± 0.21%, EE% was 88.67 ± 3.06%. Carrier material biocompatibility and loaded micelle cytotoxicity were assessed using the CCK-8 method, demonstrating excellent biocompatibility. Under the same drug concentration, TPL/PTX-PMs were the most toxic to tumour cells and had the strongest proliferation inhibitory effect. Cellular uptake assays revealed that TPL/PTX-PMs significantly increased intracellular drug concentration and enhanced antitumor activity. Overall, pH-responsive micellar co-delivery of TPL and PTX is a promising approach for breast cancer therapy.


Assuntos
Neoplasias da Mama , Diterpenos , Compostos de Epóxi , Micelas , Paclitaxel , Fenantrenos , Polímeros , Diterpenos/farmacologia , Diterpenos/química , Diterpenos/administração & dosagem , Compostos de Epóxi/química , Fenantrenos/química , Fenantrenos/farmacologia , Fenantrenos/administração & dosagem , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Paclitaxel/farmacologia , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Paclitaxel/química , Concentração de Íons de Hidrogênio , Feminino , Polímeros/química , Portadores de Fármacos/química , Células MCF-7 , Liberação Controlada de Fármacos , Linhagem Celular Tumoral , Polietilenoglicóis/química , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
8.
Bioelectrochemistry ; 156: 108627, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38142545

RESUMO

The level of folate receptor (FR) has become one of the independent factors for measuring human tumor diseases. The precise quantification of FR is helpful for the early diagnosis and subsequent treatment of tumors. The modification of electrodes is a key issue in ensuring and enhancing the electrochemical biosensing ability. In this study, we in-situ synthesized a nanocomposite material with excellent conductivity and stability by grafting first-generation poly(amidoamine) dendrimers onto the MXene (Ti3C2TX) as the immobilized matrix (PAMAM@MXene). An electrochemical sensor was developed for FR monitor by loading the PAMAM@MXene on screen-printed carbon electrodes (SPCEs). Scanning electron microscopy (SEM) supported the effective synthesis of PAMAM@MXene. Under optimal conditions, the prepared sensor achieved the quantification of FR with a wide range of concentrations from 10 ng/mL to 1000 ng/mL with a detection limit (LOD) of 5.6 ng/mL. It also exhibited satisfactory selectivity, reproducibility, and stability, which provided the possibility for expanding new pathways in the detection of clinical FR.


Assuntos
Técnicas Biossensoriais , Neoplasias , Nitritos , Elementos de Transição , Humanos , Reprodutibilidade dos Testes , Técnicas Eletroquímicas , Eletrodos , Ácido Fólico
9.
J Am Chem Soc ; 135(33): 12172-5, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23924191

RESUMO

The DNA origami technology holds great promise for the assembly of nanoscopic technological devices and studies of biochemical reactions at the single-molecule level. For these, it is essential to establish well controlled attachment of functional materials to predefined sites on the DNA origami nanostructures for reliable measurements and versatile applications. However, the two-sided nature of the origami scaffold has shown limitations in this regard. We hypothesized that holes of the commonly used two-dimensional DNA origami designs are large enough for the passage of single-stranded (ss)-DNA. Sufficiently long ssDNA initially located on one side of the origami should thus be able to "thread" to the other side through the holes in the origami sheet. By using an origami sheet attached with patterned biotinylated ssDNA spacers and monitoring streptavidin binding with atomic force microscopic (AFM) imaging, we provide unambiguous evidence that the biotin ligands positioned on one side have indeed threaded through to the other side. Our finding reveals a previously overlooked critical design feature that should provide new interpretations to previous experiments and new opportunities for the construction of origami structures with new functional capabilities.


Assuntos
DNA de Cadeia Simples/química , Nanoestruturas/química , Conformação de Ácido Nucleico , Simulação de Dinâmica Molecular
10.
J Am Chem Soc ; 135(2): 696-702, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23237536

RESUMO

Self-assembled DNA origami nanostructures have shown great promise for bottom-up construction of complex objects with nanoscale addressability. Here we show that DNA origami-based 1D nanoribbons and nanotubes are one-pot assembled with controllable sizes and nanoscale addressability with high speed (within only 10-20 min), exhibiting extraordinarily high cooperativity that is often observed in assembly of natural molecular machines in cells (e.g. ribosome). By exploiting the high specificity of DNA-based self-assembly, we can precisely anchor proteins on these DNA origami nanostructures with sub-10 nm resolution and at the single-molecule level. We attach a pair of enzymes (horseradish peroxidase and glucose oxidase) at the inner side of DNA nanotubes and observe high coupling efficiency of enzyme cascade within this confined nanospace. Hence, DNA nanostructures with such unprecedented properties shed new light on the design of nanoscale bioreactors and nanomedicine and provide an artificial system for studying enzyme activities and cascade in highly organized and crowded cell-mimicking environments.


Assuntos
Reatores Biológicos , DNA/química , Nanoestruturas/química , Nanotecnologia , Microscopia de Força Atômica
11.
Chemphyschem ; 14(10): 2101-11, 2013 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-23788363

RESUMO

We have briefly overviewed recent efforts in the electrochemistry of single transition metal complex, redox metalloprotein, and redox-marked oligonucleotide (ON) molecules. We have particularly studied self-assembled molecular monolayers (SAMs) of several 5'-C6-SH single- (ss) and double-strand (ds) ONs immobilized on Au(111) electrode surfaces via Au-S bond formation, using a combination of nucleic acid chemistry, electrochemistry and electrochemically controlled scanning tunnelling microscopy (in situ STM). Ds ONs stabilized by multiply charged cations and locked nucleic acid (LNA) monomers have been primary targets, with a view on stabilizing the ds-ONs and improving voltammetric signals of intercalating electrochemical redox probes. Voltammetric signals of the intercalator anthraquinone monosulfonate (AQMS) at ds-DNA/Au(111) surfaces diluted by mercaptohexanol are significantly sharpened and more robust in the presence than in the absence of [Co(NH3)6](3+). AQMS also displays robust Faradaic voltammetric signals specific to the ds form on binding to similar LNA/Au(111) surfaces, but this signal only evolves after successive voltammetric scanning into negative potential ranges. Triply charged spermidine (Spd) invokes itself a strong voltammetric signal, which is specific to the ds form and fully matched sequences. This signal is of non-Faradaic, capacitive origin but appears in the same potential range as the Faradaic AQMS signal. In situ STM shows that molecular scale structures of the size of Spd-stabilized ds-ONs are densely packed over the Au(111) surface in potential ranges around the capacitive peak potential.


Assuntos
DNA/química , Técnicas Eletroquímicas , Ouro/química , Metaloproteínas/química , Eletrodos , Tamanho da Partícula , Propriedades de Superfície
12.
Front Bioeng Biotechnol ; 11: 1263715, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026899

RESUMO

Genetic engineering of complex metabolic pathways and multiple traits often requires the introduction of multiple genes. The construction of plasmids carrying multiple DNA fragments plays a vital role in these processes. In this study, the Gibson assembly and Gateway cloning combined Pyramiding Stacking of Multigenes (PSM) system was developed to assemble multiple transgenes into a single T-DNA. Combining the advantages of Gibson assembly and Gateway cloning, the PSM system uses an inverted pyramid stacking route and allows fast, flexible and efficient stacking of multiple genes into a binary vector. The PSM system contains two modular designed entry vectors (each containing two different attL sites and two selectable markers) and one Gateway-compatible destination vector (containing four attR sites and two negative selection markers). The target genes are primarily assembled into the entry vectors via two parallel rounds of Gibson assembly reactions. Then, the cargos in the entry constructs are integrated into the destination vector via a single tube Gateway LR reaction. To demonstrate PSM's capabilities, four and nine gene expression cassettes were respectively assembled into the destination vector to generate two binary expression vectors. The transgenic analysis of these constructs in Arabidopsis demonstrated the reliability of the constructs generated by PSM. Due to its flexibility, simplicity and versatility, PSM has great potential for genetic engineering, synthetic biology and the improvement of multiple traits.

13.
Microbiol Spectr ; : e0448922, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36912679

RESUMO

Mycoplasma pneumoniae is the most common pathogen causing respiratory tract infection, and the P1 protein on its adhesion organelle plays a crucial role during the pathogenic process. Currently, there are many studies on P1 and receptors on host cells, but the adhesion mechanism of P1 protein is still unclear. In this study, a modified virus overlay protein binding assay (VOPBA) and liquid chromatography-mass spectrometry (LC-MS) were performed to screen for proteins that specifically bind to the region near the carboxyl terminus of the recombinant P1 protein (rP1-C). The interaction between rP1-C and vimentin or ß-4-tubulin were confirmed by far-Western blotting and coimmunoprecipitation. Results verified that vimentin and ß-4-tubulin were mainly distributed on the cell membrane and cytoplasm of human bronchial epithelial (BEAS-2B) cells, but only vimentin could interact with rP1-C. The results of the adhesion and adhesion inhibition assays indicated that the adhesion of M. pneumoniae and rP1-C to cells could be partly inhibited by vimentin and its antibody. When vimentin was downregulated with the corresponding small interfering RNA (siRNA) or overexpressed in BEAS-2B cells, the adhesion of M. pneumoniae and rP1-C to cells was decreased or increased, respectively, which indicated that vimentin was closely associated with the adhesion of M. pneumoniae and rP1-C to BEAS-2B cells. Our results demonstrate that vimentin could be a receptor on human bronchial epithelial cells for the P1 protein and plays an essential role in the adhesion of M. pneumoniae to cells, which may clarify the pathogenesis of M. pneumoniae. IMPORTANCE Mycoplasma pneumoniae is the most common pathogen causing respiratory tract infection, and the P1 protein on its adhesion organelle plays a crucial role during the pathogenic process. A variety of experiments, including enzyme-linked immunosorbent assay (ELISA), coimmunoprecipitation, adhesion, and adhesion inhibition assay, have demonstrated that the M. pneumoniae P1 protein can interact with vimentin, that the adhesion of M. pneumoniae and recombinant P1 protein to BEAS-2B cells was affected by the expression level of vimentin. This provides a new idea for the prevention and treatment of Mycoplasma pneumoniae infection.

14.
Colloids Surf B Biointerfaces ; 228: 113419, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37393700

RESUMO

Paclitaxel is one of the most effective chemotherapeutic drugs which processes the obvious curative effect for a broad range of cancers including breast, ovarian, lung, and head & neck cancers. Though some novel paclitaxel-loaded formulations have been developed, the clinical application of the paclitaxel is still limited due to its toxicity and solubility issues. Over the past decades, we have seen rapid advances in applying nanocarriers in paclitaxel delivery systems. The nano-drug delivery systems offer unique advantages in enhancing the aqueous solubility, reducing side effects, increasing permeability, prolonging circulation half-life of paclitaxel. In this review, we summarize recent advances in developing novel paclitaxel-loaded nano delivery systems based on nanocarriers. These nanocarriers show great potentials in overcoming the disadvantages of pure paclitaxel and as a result improving the efficacy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Sistemas de Liberação de Fármacos por Nanopartículas , Medicina de Precisão , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
15.
Analyst ; 137(19): 4435-9, 2012 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-22898737

RESUMO

We have coupled gold nanoparticles with horseradish peroxidase (HRP) to assemble catalytic nanoconjugates (HRP-AuNPs) for glucose detection. We found that a proper mixing ratio of HRP/AuNPs can significantly improve catalytic activity for the cascade reaction, an effect arising from increased spatial coupling between enzymes. Such gold nanoparticle-based nanoconjugates are shown to be promising nanosensors for glucose.


Assuntos
Colorimetria , Glucose/análise , Ouro/química , Peroxidase do Rábano Silvestre/metabolismo , Nanopartículas Metálicas/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Peroxidase do Rábano Silvestre/química
16.
Colloids Surf B Biointerfaces ; 220: 112944, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36274398

RESUMO

With the continuous increasing number of cancer patients worldwide, there has been great interest in developing the targeted delivery anti-cancer drugs. The drug concentration reaching the tumor site is not enough to achieve a good therapeutic effect if it relies only on passive targeted drug delivery. In a long-lasting effort to improve the anti-cancer effect of drugs, surface ligand modification to nanocarriers has been actively explored to greatly improve the targeting ability, induce apoptosis in tumor cells, and prolong the drug circulation time in blood. This present review provides an overview of the effects of surface ligand modifications on the properties of anti-tumor nanocarriers. The first part presents the targeting mechanisms of nanocarriers. The second part focuses on recent progress in types of surface modification ligands exploited for anti-tumor nanocarriers. And the third part encompasses the effect of surface modifications on the properties of nanocarriers. In addition, the perspective in this field is also discussed.


Assuntos
Nanopartículas , Neoplasias , Humanos , Portadores de Fármacos/uso terapêutico , Ligantes , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico
17.
Biochim Biophys Acta Mol Basis Dis ; 1867(1): 165966, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931889

RESUMO

BACKGROUND: Esophageal Squamous Cell Carcinoma (ESCC) is an aggressive malignancy, leading to more than 250,000 deaths in China every year. However, the pathogenesis of ESCC remains unclear, which hinders the diagnosis and treatment of the disease in clinic. METHOD: To elucidate underlying mechanism and identify potential biomarkers, an integrative strategy of combining transcriptome and metabolome has been implemented to find potential causal genes and metabolites for ESCC. RESULTS: At the transcriptional level, dysregulated genes in ESCC patients were identified and pathway enrichment analysis discovered tyrosine metabolic pathway as a promising target. Subsequently, up- and down-stream metabolites of tyrosine pathway were explored through targeted metabolome approach. Five metabolites, i.e. phenylalanine, 4-hydroxyphenyllactic acid, 3,4-dihydroxyphenylalanine, 3,4-dihydroxyphenylacetic acid and tyrosine were identified as diagnosis biomarkers for ESCC and metastatic ESCC patients. A biological model incorporating both transcriptional and metabolic dysregulation was also established to illustrate the potential mechanism of tumorigenesis and metastasis for ESCC. CONCLUSION: Integrative transcriptomics and metabolomics analysis suggested that tyrosine pathway was essential for the tumorigenesis and metastasis of ESCC primarily through altering immune response and regulating tumor microenvironment. This research sheds light on the pathogenesis of ESCC and discovers potential biomarkers for the diagnosis of the disease.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Metaboloma , Transcriptoma , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Microambiente Tumoral
18.
Biomacromolecules ; 10(12): 3335-40, 2009 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-19924999

RESUMO

Fabrication of poly(dimethylsiloxane) (PDMS)/poly(methyl methacrylate) (PMMA) nanofibers is critical to harness the advantage of nanostructured membrane applied in protein microarrays. Electrospinning (ES) of PDMS nanofibers is challenging because of the relatively low molecular weight of PDMS prepolymer. We report a strategy to fabricate PDMS/PMMA nanofibers via ES by introducing carrier polymer PMMA into PDMS solutions to supplement the deficiency of chain entanglements in the PDMS prepolymer. The prepared PDMS/PMMA nanofibrous membrane (PDMS/PMMA NFM) was successfully used as substrates for protein microarrays. The results of immunoassays showed the superior performance of PDMS/PMMA NFM as 3D substrate for protein microarrays; the limit-of-detection (LOD) on PDMS/PMMA NFM was 32 times lower than that on nitrocellulose membrane. The realization of ES PDMS extends the scope of ES materials from thermoplastic polymers to thermosetting materials. Given the simplicity, low cost, and high efficiency of ES technology, we believe that PDMS/PMMA NFM is a promising 3D substrate for protein microarrays.


Assuntos
Dimetilpolisiloxanos/química , Membranas Artificiais , Nanofibras/química , Polimetil Metacrilato/química , Análise Serial de Proteínas , Eletricidade
19.
Bioelectrochemistry ; 127: 163-170, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30831354

RESUMO

Long-term accumulation of organophosphate pesticides in environment presents a potential hazard to human and animal health. Towards this, a highly sensitive amperometric AChE-biosensor based on conjugated polymer and Ag-rGO-NH2 nanocomposite has been successfully developed. First, 4, 7-di (furan-2-yl) benzo thiadiazole (FBThF) was electrochemically polymerized on the electrode surface. Then, Ag-rGO-NH2 nanocomposite and acetylcholinesterase (AChE) are modified on the polymer membrane surface. In this way, a novel amperometric AChE-biosensor was successfully prepared. The as-prepared biosensor possessed excellent conductivity, catalytic activity, and biocompatibility which were attributed to the synergistic effects of poly(FBThF) and Ag-rGO-NH2 and provided a hydrophilic surface for AChE adhesion. Under optimized conductions, the linear range was 0.099-9.9 µg L-1 with a regression coefficient of 0.9947 for malathion, 0.0206-2.06 µg L-1 with a regression coefficient of 0.9969 for trichlorfon. The detection limit is calculated to be about 0.032 µg L-1 for malathion and 0.001 µg L-1 for trichlorfon (S/N = 3). Moreover, the biosensor exhibited acceptable reproducibility and long-term stability, which makes it possible to provide a novel and promising tool for analysis of organophosphate pesticides.


Assuntos
Acetilcolinesterase/química , Técnicas Biossensoriais/métodos , Grafite/química , Nanocompostos/química , Organofosfatos/análise , Praguicidas/análise , Prata/química , Aminação , Água Potável/análise , Enzimas Imobilizadas/química , Limite de Detecção , Malus/química , Oxirredução , Polímeros/química , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise
20.
Talanta ; 201: 119-125, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122401

RESUMO

Glycated hemoglobin (HbA1c) represents the average glucose level over the past three months and has been considered as the most important biomarker for the diagnosis of Type Ⅱ diabetes (T2D). Herein, a label-free and quantitative electrochemical biosensor based on 4-mercaptophenylboronic acid (4-MPBA) modified gold nano-flowers (Au NFs) substrate was developed for the determination of HbA1c. Under optimal conditions, the linear dynamic ranges of HbA1c (5 µg/mL - 1000 µg/mL) and HbA1c% (2%-20%) by cyclic voltammetry were achieved. The electrochemical biosensor showed great detection specificity towards HbA1c and relatively stability after storage at 4 °C. This method could also be applied in human serum system which holds great potential to be applied to monitor real blood samples of diabetes patients. In human serum system, the recovery rate could reach 103.8% and 99.0%. It could achieve fast detection, the total analysis time was less than 65 min, and the detection time was less than 10 s. Moreover, in terms of fabrication process, operation procedure, detection time and cost, this technique was superior to the current HbA1c detection methods suggesting great promise for the practical clinical use in the future.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Hemoglobinas Glicadas/análise , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/instrumentação , Ácidos Borônicos/química , Carbono/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Hemoglobinas Glicadas/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Oxirredução , Compostos de Sulfidrila/química
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