Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Anal Chem ; 96(25): 10380-10390, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38860916

RESUMO

To reduce the risk of atherosclerotic disease, it is necessary to not only diagnose the presence of atherosclerotic plaques but also assess the vulnerability risk of plaques. Accurate detection of the reactive oxygen species (ROS) level at plaque sites represents a reliable way to assess the plaque vulnerability. Herein, through a simple one-pot reaction, two near-infrared (NIR) fluorescent dyes, one is ROS responsive and the other is inert to ROS, are coassembled in an amphiphilic amino acid-assembled nanoparticle. In the prepared NIR fluorescent amino acid nanoparticle (named FANP), the fluorescent properties and ROS-responsive behaviors of the two fluorescent dyes are well maintained. Surface camouflage through red blood cell membrane (RBCM) encapsulation endows the finally obtained FANP@RBCM nanoprobe with not only further reduced cytotoxicity and improved biocompatibility but also increased immune escape capability, prolonged blood circulation time, and thus enhanced accumulation at atherosclerotic plaque sites. In vitro and in vivo experiments demonstrate that FANP@RBCM not only works well in probing the occurrence of atherosclerotic plaques but also enables plaque vulnerability assessment through the accurate detection of the ROS level at plaque sites in a reliable ratiometric mode, thereby holding great promise as a versatile tool for the diagnosis and risk assessment of atherosclerotic disease.


Assuntos
Aminoácidos , Corantes Fluorescentes , Nanopartículas , Placa Aterosclerótica , Espécies Reativas de Oxigênio , Placa Aterosclerótica/diagnóstico por imagem , Animais , Espécies Reativas de Oxigênio/metabolismo , Corantes Fluorescentes/química , Nanopartículas/química , Camundongos , Aminoácidos/química , Humanos , Medição de Risco , Imagem Óptica , Raios Infravermelhos , Células RAW 264.7
2.
Anal Chem ; 96(6): 2692-2701, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38305871

RESUMO

In recent years, the CRISPR/Cas12a-based sensing strategy has shown significant potential for specific target detection due to its rapid and sensitive characteristics. However, the "always active" biosensors are often insufficient to manipulate nucleic acid sensing with high spatiotemporal control. It remains crucial to develop nucleic acid sensing devices that can be activated at the desired time and space by a remotely applied stimulus. Here, we integrated photoactivation with the CRISPR/Cas12a system for DNA and RNA detection, aiming to provide high spatiotemporal control for nucleic acid sensing. By rationally designing the target recognition sequence, this photoactivation CRISPR/Cas12a system could recognize HPV16 and survivin, respectively. We combined the lateral flow assay strip test with the CRISPR/Cas12a system to realize the visualization of nucleic acid cleavage signals, displaying potential instant test application capabilities. Additionally, we also successfully realized the temporary control of its fluorescent sensing activity for survivin by photoactivation in vivo, allowing rapid detection of target nucleic acids and avoiding the risk of contamination from premature leaks during storage. Our strategy suggests that the CRISPR/Cas12a platform can be triggered by photoactivation to sense various targets, expanding the technical toolbox for precise biological and medical analysis. This study represents a significant advancement in nucleic acid sensing and has potential applications in disease diagnosis and treatment.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , Survivina/genética , Biomarcadores , Testes Imediatos
3.
Anal Chem ; 96(16): 6426-6435, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38604773

RESUMO

Sensors designed based on the trans-cleavage activity of CRISPR/Cas12a systems have opened up a new era in the field of biosensing. The current design of CRISPR/Cas12-based sensors in the "on-off-on" mode mainly focuses on programming the activator strand (AS) to indirectly switch the trans-cleavage activity of Cas12a in response to target information. However, this design usually requires the help of additional auxiliary probes to keep the activator strand in an initially "blocked" state. The length design and dosage of the auxiliary probe need to be strictly optimized to ensure the lowest background and the best signal-to-noise ratio. This will inevitably increase the experiment complexity. To solve this problem, we propose using AS after the "RESET" effect to directly regulate the Cas12a enzymatic activity. Initially, the activator strand was rationally designed to be embedded in a hairpin structure to deprive its ability to activate the CRISPR/Cas12a system. When the target is present, target-mediated strand displacement causes the conformation change in the AS, the hairpin structure is opened, and the CRISPR/Cas12a system is reactivated; the switchable structure of AS can be used to regulate the degree of activation of Cas12a according to the target concentration. Due to the advantages of low background and stability, the CRISPR/Cas12a-based strategy can not only image endogenous biomarkers (miR-21) in living cells but also enable long-term and accurate imaging analysis of the process of exogenous virus invasion of cells. Release and replication of virus genome in host cells are indispensable hallmark events of cell infection by virus; sensitive monitoring of them is of great significance to revealing virus infection mechanism and defending against viral diseases.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , MicroRNAs , Sistemas CRISPR-Cas/genética , Técnicas Biossensoriais/métodos , Humanos , MicroRNAs/análise , MicroRNAs/metabolismo , Regulação Alostérica , Proteínas Associadas a CRISPR/metabolismo , Endodesoxirribonucleases/metabolismo , Endodesoxirribonucleases/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Células HEK293
4.
Anal Chem ; 95(42): 15725-15735, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37819747

RESUMO

The trans-cleavage activity of CRISPR/Cas12a has been widely used in biosensing. However, many CRISPR/Cas12a-based biosensors, especially those that work in "on-off-on" mode, usually suffer from high background and thus impossible intracellular application. Herein, this problem is efficiently overcome by elaborately designing the activator strand (AS) of CRISPR/Cas12a using the "RESET" effect found by our group. The activation ability of the as-designed AS to CRISPR/Cas12a can be easily inhibited, thus assuring a low background for subsequent biosensing applications, which not only benefits the detection sensitivity improvement of CRISPR/Cas12a-based biosensors but also promotes their applications in live cells as well as makes it possible to design high-performance biosensors with greatly improved flexibility, thus achieving the analysis of a wide range of targets. As examples, by using different strategies such as strand displacement, strand cleavage, and aptamer-substrate interaction to reactivate the inhibited enzyme activity, several CRISPR/Cas12a-based biosensing systems are developed for the sensitive and specific detection of different targets, including nucleic acid (miR-21), biological small molecules (ATP), and enzymes (hOGG1), giving the detection limits of 0.96 pM, 8.6 µM, and 8.3 × 10-5 U/mL, respectively. Thanks to the low background, these biosensors are demonstrated to work well for the accurate imaging analysis of different biomolecules in live cells. Moreover, we also demonstrate that these sensing systems can be easily combined with lateral flow assay (LFA), thus holding great potential in point-of-care testing, especially in poorly equipped or nonlaboratory environments.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , Bioensaio , Processamento de Imagem Assistida por Computador , Oligonucleotídeos
5.
Sheng Li Xue Bao ; 75(2): 197-204, 2023 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-37089094

RESUMO

The purpose of this study was to establish a suitable method for extracting cerebrospinal fluid (CSF) from C57BL/6 mice. A patch clamp electrode puller was used to draw a glass micropipette, and a brain stereotaxic device was used to fix the mouse's head at an angle of 135° from the body. Under a stereoscopic microscope, the skin and muscle tissue on the back of the mouse's head were separated, and the dura mater at the cerebellomedullary cistern was exposed. The glass micropipette (with an angle of 20° to 30° from the dura mater) was used to puncture at a point 1 mm inboard of Y-shaped dorsal vertebral artery for CSF sampling. After the first extraction, the glass micropipette was connected with a 1 mL sterile syringe to form a negative pressure device for the second extraction. The results showed that the successful rate of CSF extraction was 83.33% (30/36). Average CSF extraction amount was (7.16 ± 0.43) µL per mouse. In addition, C57BL/6 mice were given intranasally ferric ammonium citrate (FAC) to establish a model of brain iron accumulation, and the CSF extraction technique established in the present study was used for sampling. The results showed that iron content in the CSF from the normal saline control group was not detected, while the iron content in the CSF from FAC-treated group was (76.24 ± 38.53) µmol/L, and the difference was significant. These results suggest that glass micropipette vacuum technique of CSF sampling established in the present study has the advantages of simplicity, high success rate, large extraction volume, and low bleeding rate, and is suitable for the research on C57BL/6 mouse neurological disease models.


Assuntos
Encéfalo , Cisterna Magna , Camundongos , Animais , Vácuo , Camundongos Endogâmicos C57BL , Líquido Cefalorraquidiano
6.
Anal Chem ; 94(22): 8050-8057, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35615910

RESUMO

The trans-cleavage activity of CRISPR/Cas12a has been widely used in biosensing applications. However, the lack of exploration on the fundamental properties of CRISPR/Cas12a not only discourages further in-depth studies of the CRISPR/Cas12a system but also limits the design space of CRISPR/Cas12a-based applications. Herein, a "RESET" effect (random extending sequences enhance trans-cleavage activity) is discovered for the activation of CRISPR/Cas12a trans-cleavage activity. That is, a single-stranded DNA, which is too short to work as the activator, can efficiently activate CRISPR/Cas12a after being extended a random sequence from its 3'-end, even when the random sequence folds into secondary structures. The finding of the "RESET" effect enriches the CRISPR/Cas12a-based sensing strategies. Based on this effect, two CRISPR/Cas12a-based biosensors are designed for the sensitive and specific detection of two biologically important enzymes.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , DNA de Cadeia Simples/genética
7.
Anal Chem ; 93(48): 16231-16239, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34818886

RESUMO

Methods to detect and quantify disease biomarkers with high specificity and sensitivity in biological fluids play a key role in enabling clinical diagnosis, including point-of-care testing. Myeloperoxidase (MPO) is an emerging biomarker for the detection of inflammation, neurodegenerative diseases, and cardiovascular disease, where excess MPO can lead to oxidative damage to biomolecules in homeostatic systems. While numerous methods have been developed for MPO analysis, most techniques are challenging in clinical applications due to the lack of amplification methods, high cost, or other practical drawbacks. Enzyme-linked immunosorbent assays are currently used for the quantification of MPO in clinical practice, which is often limited by the availability of antibodies with high affinity and specificity and the significant nonspecific binding of antibodies to the analytical surface. In contrast, nucleic acid-based biosensors are of interest because of their simplicity, fast response time, low cost, high sensitivity, and low background signal, but detection targets are limited to nucleic acids and non-nucleic acid biomarkers are rare. Recent studies reveal that the modification of a genome in the form of phosphorothioate is specifically sensitive to the oxidative effects of the MPO/H2O2/Cl- system. We developed an oxidative cleavage-based three-dimensional DNA biosensor for rapid, ratiometric detection of HOCl and MPO in a "one-pot" method, which is simple, stable, sensitive, specific, and time-saving and does not require a complex reaction process, such as PCR and enzyme involvement. The constructed biosensor has also been successfully used for MPO detection in complex samples. This strategy is therefore of great value in disease diagnosis and biomedical research.


Assuntos
Técnicas Biossensoriais , Ácido Hipocloroso , DNA , Peróxido de Hidrogênio , Estresse Oxidativo , Peroxidase/metabolismo
8.
Analyst ; 146(8): 2600-2608, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33721010

RESUMO

Accurate and specific analysis of adenosine triphosphate (ATP) expression levels in living cells can provide valuable information for understanding cell metabolism, physiological activities and pathologic mechanisms. Herein, DNA nanolantern-based split aptamer nanoprobes are prepared and demonstrated to work well for in situ analysis of ATP expression in living cells. The nanoprobes, which carry multiple split aptamer units on the surface, are easily and inexpensively prepared by a "one-pot" assembly reaction of four short oligonucleotide strands. A series of characterization experiments verify that the nanoprobes have good monodispersity, strong biostability, high cell internalization efficiency, and fluorescence resonance energy transfer (FRET)-based ratiometric response to ATP in the concentration range covering the entire intracellular ATP expression level. By changing the intracellular ATP level via different treatments, the nanoprobes are demonstrated to show excellent performance in intracellular ATP expression analysis, giving a highly ATP concentration-dependent ratiometric fluorescence signal output. ATP-induced formation of large-sized DNA aggregates not only amplifies the FRET signal output, but also makes in situ ATP-imaging analysis in living cells possible. In situ responsive crosslinking of nanoprobes also makes them capable of lighting up the mitochondria of living cells. By simply changing the split aptamer sequence, the proposed DNA nanolantern-based split aptamer strategy might be easily extended to other targets.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Trifosfato de Adenosina , DNA , Sondas de DNA , Mitocôndrias
9.
Anal Chem ; 91(8): 5244-5251, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30883097

RESUMO

An ultimate goal of synthetic DNA motor studies is to mimic natural protein motors in biological systems. Here, we rationally designed a highly integrated and biostable DNA motor system with high potential for living body operation, through simple assembly of a Mn2+-dependent DNAzyme-powered DNA motor with a degradable MnO2 nanosheet. The motor system shows outstanding high integration and improved biostability. High integration confers the motor system with the ability to deliver all the core components to the target sites as a whole, thus, enabling precise control of the spatiotemporal distribution of these components and achieving high local concentrations. At the target sites, reduction of the MnO2 nanosheet by intracellular glutathione (GSH) not only releases the DNA motor, which can then be initiated by the intracellular target, but also produces Mn2+ in situ to power the autonomous and progressive operation of the DNA motor. Interestingly, the resultant consumption of GSH in turn protects the DNA motor from destruction by physiological GSH, thus, conferring our motor system with improved biostability, reduced false-positive outputs, and consequently, an increased potential to be applied in a living body. As a proof of concept, the highly integrated DNA motor system was demonstrated to work well for amplified imaging detection of survivin mRNA (mRNA), an important tumor biomarker, in both living cancer cells and living tumor-bearing mice. This work reveals concepts and strategies promoting synthetic DNA motor applications in biological systems.


Assuntos
DNA de Neoplasias/química , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , DNA Catalítico/química , DNA Catalítico/metabolismo , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Glutationa/química , Células HeLa , Humanos , Compostos de Manganês/química , Compostos de Manganês/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanoestruturas/química , Neoplasias Experimentais/diagnóstico por imagem , Imagem Óptica , Óxidos/química , Óxidos/metabolismo , Tamanho da Partícula , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Propriedades de Superfície , Survivina/química , Survivina/genética , Survivina/metabolismo
10.
Anal Chem ; 91(20): 13165-13173, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31512479

RESUMO

The introduction of nanotechnology can overcome some inherent drawbacks of traditional DNA probes, thus promoting their applications in living cells. Herein, a three-dimensional DNA nanostructure, a DNA nanolantern, was prepared via simple nucleotide hybridization of four short-stranded oligonucleotides and successfully applied to the construction of a novel DNA probe and signal amplifier. Compared to most reported DNA nanostructures, a DNA nanolantern shows the distinct advantages of low cost, easy design and preparation, more and arbitrary adjusted probe numbers, and high fluorescence resonance energy transfer (FRET) signal readout. Compared to traditional DNA probes, the constructed nanolantern-based one has improved cell internalization efficiency, enhanced biostability, accelerated reaction kinetics, excellent biocompatibility, and greatly reduced false-positive output and was demonstrated to work well for probing the expression level of tumor-related mRNA and microRNA in living cells. The DNA nanolantern can also be easily integrated with some reported signal amplification strategies, e.g., isothermal hybridization chain reaction (HCR), and the obtained signal amplifier combines the advantages of the DNA nanolantern and the HCR, enabling sensitive imaging detection of ultralow abundance targets in living cells. This work demonstrated that this simple DNA nanostructure can not only improve the performance of traditional DNA probes but can also be easily integrated with reported DNA-based strategy and technology, thus showing a broad application prospect.


Assuntos
Biomarcadores Tumorais/análise , Sondas de DNA/química , DNA/química , MicroRNAs/análise , Nanoestruturas/química , RNA Mensageiro/análise , Linhagem Celular Tumoral , DNA/genética , Sondas de DNA/genética , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Humanos , Limite de Detecção , MicroRNAs/genética , Hibridização de Ácido Nucleico , RNA Mensageiro/genética , Timidina Quinase/genética
11.
Biochem Biophys Res Commun ; 503(2): 513-520, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29746866

RESUMO

The objective of the study is to calculate the role and underlying the molecular mechanisms of caveolin-1 (Cav-1) in atherosclerosis (AS). Cav-1 was mainly expressed in the endothelial cells of atherosclerotic lesions in both human patients and apolipoprotein E deficient (ApoE-/-) mice. Cav-1 deficiency (Cav-1-/-) attenuated high-fat diet (HFD)-induced atherosclerotic lesions in ApoE-/- mice, supported by the reduced aortic plaques. Cav-1-/- reduced the macrophage content and decreased the release of inflammation-related cytokines or chemokine in serum or abdominal aortas, accompanied with the inactivation of inhibitor κB kinase κ (IKKß)/p65/IκBα signaling pathway. Also, the activity of mitogen-activated protein kinases 7/c-Jun-N-terminal kinase (MKK7/JNK) signaling was decreased by Cav-1-/-. In addition, oxidative stress induced by HFD in ApoE-/- mice was alleviated by Cav-1-/-. In response to HFD, Cav-1-/- markedly reduced triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDLC) and very low-density lipoprotein-cholesterol (VLDLC) in serum of HFD-fed ApoE-/- mice, whereas enhanced high-density lipoprotein-cholesterol (HDLC) contents. Consistent with these findings, haematoxylin and eosin (H&E) and Oil Red O staining showed fewer lipid droplets in the liver of Cav-1-deficient mice. Further, real time-quantitative PCR (RT-qPCR) analysis indicated that Cav-1-/- alleviated dyslipidemia both in liver and abdominal aortas of ApoE-/- mice fed with HFD. Cav-1 inhibition-induced attenuation of inflammatory response, oxidative stress and dyslipidemia were confirmed in vitro using mouse vascular smooth muscle cells (VSMCs) treated with ox-LDL. Surprisingly, the processes regulated by Cav-1-knockdown could be abolished through promoting JNK activation in ox-LDL-treated VSMCs. In conclusion, Cav-1 expression could promote HFD-induced AS in a JNK-dependent manner.


Assuntos
Aterosclerose/metabolismo , Caveolina 1/metabolismo , Sistema de Sinalização das MAP Quinases , Animais , Aterosclerose/genética , Aterosclerose/patologia , Caveolina 1/análise , Caveolina 1/genética , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Dislipidemias/genética , Dislipidemias/metabolismo , Dislipidemias/patologia , Deleção de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo
12.
Dermatol Ther ; 31(3): e12598, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29642271

RESUMO

This study aims to explore the expression of RORγt, BATF, and IL-17 in Chinese vitiligo patients with 308 nm excimer laser treatment. One hundred and sixty-four vitiligo patients treated with 308 nm excimer laser were enrolled as Case group and 137 health examiners as Control group. Quantitative real-time polymerase chain reaction and immunohistochemistry were conducted to detect the expressions of RORγt, BATF, and IL-17. Expression of RORγt, BATF, IL-17A, and IL-17F were higher in Case group than Control group, with the diagnostic accuracy of 88.04, 87.38, 97.34, and 89.04%, respectively. Pearson correlation analysis showed a positive correlation in RORγt, BATF, IL-17A, and IL-17F mRNAs in vitiligo patients. Moreover, their expressions were higher in active vitiligo patients than stable ones. Besides, the expressions of RORγt, BATF, IL-17A, and IL-17F in vitiligo skin were significantly higher than those in non lesional skin and normal controls. After treatment, their expressions were significantly decreased. Active vitiligo and the high expressions of RORγt, BATF, and IL-17F were the independent risk factors for the ineffectiveness of 308 nm excimer laser treatment. The expressions of RORγt, BATF, IL-17 were significantly enhanced in vitiligo patients, which were correlated with the activity of vitiligo and 308 nm excimer laser therapeutic effects.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Interleucina-17/genética , Lasers de Excimer/uso terapêutico , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Vitiligo/cirurgia , Adolescente , Adulto , Idoso , Fatores de Transcrição de Zíper de Leucina Básica/análise , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Interleucina-17/análise , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/análise , Reação em Cadeia da Polimerase em Tempo Real , Vitiligo/metabolismo , Vitiligo/patologia , Adulto Jovem
13.
Sheng Li Xue Bao ; 70(3): 294-300, 2018 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-29926071

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the degeneration of dopaminergic neurons in the substantia nigra and the intraneuronal Lewy bodies in this area. Genetic mutations in PD pathogenesis have been explored and better understood in recent years. GBA variants are now considered to be the single largest risk factor for PD. Gaucher disease (GD) is a lysosomal storage disorder disease and an inherited deficiency of lysosomal glucocerebrosidase (GCase) arising from mutations in the gene GBA. A group of patients with GD exhibit parkinsonian symptoms, meanwhile, GBA mutations are more frequently observed in patients with PD. These lines of evidence suggest a close relationship between GBA mutations and PD. GBA mutations are associated with an earlier onset age and a distinct cognitive decline in PD. GCase loss-of-function caused by GBA mutations interferes with the degradation of α-synuclein, and α-synuclein pathology in turn inhibits normal GCase function in PD, which forms a vicious cycle. However, the exact mechanisms for this bidirectional pathogenic loop have not to be fully elucidated. In this review, we summarize the current understandings on the potential link between GBA mutations and PD pathogenesis, which may show novel insights into PD etiology and therapeutics.


Assuntos
Glucosilceramidase/genética , Mutação , Doença de Parkinson/genética , Disfunção Cognitiva , Neurônios Dopaminérgicos/patologia , Doença de Gaucher/genética , Humanos , Transtornos Parkinsonianos/genética , Fatores de Risco , Substância Negra , alfa-Sinucleína
14.
ACS Nano ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231016

RESUMO

The spacing between cells has a significant impact on cell-cell interactions, which are critical to the fate and function of both individual cells and multicellular organisms. However, accurately measuring the distance between cell membranes and the variations between different membranes has proven to be a challenging task. In this study, we employ metal-induced energy transfer (MIET) imaging/spectroscopy to determine and track the intermembrane distance and variations with nanometer precision. We have developed a DNA-based molecular adhesive called the DNA nanobrush, which serves as a cellular adhesive for connecting the plasma membranes of different cells. By manipulating the number of base pairs within the DNA nanobrush, we can modify various aspects of membrane-membrane interactions such as adhesive directionality, distance, and forces. We demonstrate that such nanometer-level changes can be detected with MIET imaging/spectroscopy. Moreover, we successfully employed MIET to measure distance variations between a cellular plasma membrane and a model membrane. This experiment not only showcases the effectiveness of MIET as a powerful tool for accurately quantifying membrane-membrane interactions but also validates the potential of DNA nanobrushes as cellular adhesives. This innovative method holds significant implications for advancing the study of multicellular interactions.

15.
J Hazard Mater ; 448: 130821, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36709736

RESUMO

Lignin, the most abundant source of renewable aromatic compounds derived from natural lignocellulosic biomass, has great potential for various applications as green materials due to its abundant active groups. However, it is still challenging to quickly construct green polymers with a certain crystallinity by utilizing lignin as a building block. Herein, new green lignin-based covalent organic polymers (LIGOPD-COPs) were one-pot fabricated with water as the reaction solvent and natural lignin as the raw material. Furthermore, by using paraformaldehyde as a protector and modulator, the LIGOPD-COPs prepared under optimized conditions displayed better crystallinity than reported lignin-based polymers, demonstrating the feasibility of preparing lignin-based polymers with improved crystallinity. The improved crystallinity confers LIGOPD-COPs with enhanced application performance, which was demonstrated by their excellent performances in sample treatment of non-targeted food safety analysis. Under optimized conditions, phytochromes, the main interfering matrices, were almost completely removed from different phytochromes-rich vegetables by LIGOPD-COPs, accompanied by "full recovery" of 90 chemical hazards. Green, low-cost, and reusable properties, together with improved crystallinity, will accelerate the industrialization and marketization of lignin-based COPs, and promote their applications in many fields.


Assuntos
Lignina , Polímeros , Lignina/química , Polímeros/química , Biomassa , Água , Solventes
16.
Talanta ; 236: 122846, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635236

RESUMO

Simultaneous detection of multiple microRNAs (miRNAs) with high sensitivity can give accurate and reliable information for clinical applications. By uniformly anchoring hairpin probes on the surface of DNA nanolantern, a three-dimensional DNA nanostructure contains abundant and adjustable modification sites, highly integrated DNA nanoprobes were designed and developed as catalytic hairpin assembly (CHA)-based signal amplifiers for enzyme-free signal amplification detection of target miRNAs. The nanolantern-based CHA (NLC) amplifiers, which were facilely prepared via a simple "one-pot" annealing method, showed enhanced biostability, improved cell internalization efficiency, accelerated CHA reaction kinetics, and increased signal amplification capability compared to the single-stranded DNA hairpin probes used in traditional CHA reaction. By co-assembling multiple hairpin probes on a DNA nanolantern surface, as-prepared NLC amplifiers were demonstrated to work well for highly sensitive and specific imaging, expression level fluctuation analysis of two miRNAs in living cells, and miRNAs-guided tumor imaging in living mice. The proposed DNA nanolantern-based nanoamplifier strategy might provide a feasible way to promote the cellular and in vivo applications of nucleic acid probes.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Animais , Catálise , DNA/genética , Camundongos , MicroRNAs/genética , Sondas de Ácido Nucleico
17.
Chem Sci ; 13(15): 4364-4371, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35509467

RESUMO

Besides gene-editing, the CRISPR/Cas12a system has also been widely used in in vitro biosensing, but its applications in live-cell biosensing are rare. One reason is lacking appropriate carriers to synchronously deliver all components of the CRISPR/Cas12a system into living cells. Herein, we demonstrate that MnO2 nanosheets are an excellent carrier of CRISPR/Cas12a due to the two important roles played by them. Through a simple mixing operation, all components of the CRISPR/Cas12a system can be loaded on MnO2 nanosheets and thus synchronously delivered into cells. Intracellular glutathione (GSH)-induced decomposition of MnO2 nanosheets not only results in the rapid release of the CRISPR/Cas12a system in cells but also provides Mn2+ as an accelerator to promote CRISPR/Cas12a-based biosensing of intracellular targets. Due to the merits of highly efficient delivery, rapid intracellular release, and the accelerated signal output reaction, MnO2 nanosheets work better than commercial liposome carriers in live-cell biosensing analysis of survivin messenger RNA (mRNA), producing much brighter fluorescence images in a shorter time. The use of MnO2 nanosheets might provide a good carrier for different CRISPR/Cas systems and achieve the rapid and sensitive live-cell biosensing analysis of different intracellular targets, thus paving a promising way to promote the applications of CRISPR/Cas systems in living cells.

18.
Chem Asian J ; 17(5): e202101315, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34989140

RESUMO

Molecular self-assembly is widely used in the fields of biosensors, molecular devices, efficient catalytic materials, and medical biomaterials. As the carrier of genetic information, DNA is a kind of biomacromolecule composed of deoxyribonucleotide units. DNA nanotechnology extends DNA of its original properties as a molecule that stores and transmits genetic information from its biological environment by taking advantage of its unique base pairing and inherent biocompatibility to produce structurally-defined supramolecular structures. With the continuously development of DNA technology, the assembly method of DNA nanostructures is not only limited on the basis of DNA hybridization but also other biochemical interactions. In this review, we summarize the latest methods used to construct higher-order DNA structures. The problems of DNA nanostructures are discussed and the future directions in this field are provided.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Pareamento de Bases , DNA/química , Nanoestruturas/química , Nanotecnologia
19.
Chem Sci ; 13(35): 10395-10405, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36277631

RESUMO

The separation and detection of circulating tumor cells (CTCs) have a significant impact on clinical diagnosis and treatment by providing a predictive diagnosis of primary tumors and tumor metastasis. But the responsive release and downstream analysis of live CTCs will provide more valuable information about molecular markers and functional properties. To this end, specific capture and controllable release methods, which can achieve the highly efficient enrichment of CTCs with strong viability, are urgently needed. DNA networks create a flexible, semi-wet three-dimensional (3D) microenvironment for cell culture, and have the potential to minimize the loss of cell viability and molecular integrity. More importantly, responsive DNA networks can be reasonably designed as smart sensors and devices to change shape, color, disassemble, and giving back to external stimuli. Here, a strategy for specifically collecting cells using a dual-aptamer DNA network is designed. The proposed strategy enables effective capture, 3D encapsulation, and responsive release of CTCs with strong viability, which can be used for downstream analysis of live cells. The programmability of CRISPR/Cas12a, a powerful toolbox for genome editing, is used to activate the responsive release of captured CTCs from the DNA network. After activation by a specified double-strand DNA (dsDNA) input, CRISPR/Cas12a cleaves the single-stranded DNA regions in the network, resulting in molecular to macroscopic changes in the network. Accompanied by the deconstruction of the DNA network into fragments, controllable cell release is achieved. The viability of released CTCs is well maintained and downstream cell analysis can be performed. This strategy uses the enzymatic properties of CRISPR/Cas12a to design a platform to improve the programmability and versatility of the DNA network, providing a powerful and effective method for capturing and releasing CTCs from complex physiological samples.

20.
Front Genet ; 13: 1047382, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36568375

RESUMO

Background: Esophageal Squamous Cell Cancer (ESCC) is an aggressive disease associated with a poor prognosis. As a newly defined form of regulated cell death, ferroptosis plays a crucial role in cancer development and treatment and might be a promising therapeutic target. However, the expression patterns of ferroptosis-related genes (FRGs) in ESCC remain to be systematically analyzed. Methods: First, we retrieved the transcriptional profile of ESCC from TCGA and GEO datasets (GSE47404, GSE23400, and GSE53625) and performed unsupervised clustering to identify different ferroptosis patterns. Then, we used the ssGSEA algorithm to estimate the immune cell infiltration of these patterns and explored the differences in immune cell abundance. Common genes among patterns were finally identified as signature genes of ferroptosis patterns. Results: Herein, we depicted the multi-omics landscape of FRGs through integrated bioinformatics analysis and identified three ESCC subtypes with distinct immune characteristics: clusters A-C. Cluster C was abundant in CD8+ T cells and other immune cell infiltration, while cluster A was immune-barren. By comparing the differently expressed genes between clusters of diverse datasets, we defined a gene signature for each cluster and successfully validated it in the TCGA-ESCC dataset. Conclusion: We provided a comprehensive insight into the expression pattern of ferroptosis genes and their interaction with immune cell infiltration. Additionally, we established a gene signature to define the ferroptosis patterns, which might be used to predict the response to immunotherapy.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA