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1.
Nat Commun ; 15(1): 8375, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333106

RESUMEN

The mechanisms underlying the natural control of hepatitis B virus (HBV) infection have long been an intriguing question. Given the wide physiological range of liver stiffness and the growing attention to the role of mechanical microenvironment in homeostasis and diseases, we investigated how physical matrix cues impact HBV replication. High matrix stiffness significantly inhibited HBV replication and activated YAP in primary hepatocyte culture system, a key molecule in mechanosignaling. YAP activation notably suppressed HBV transcription and antigen expression. Several YAP-induced genes exhibited strong anti-HBV effects. Single-cell analysis of liver tissue from male individuals with active HBV replication revealed a strong significant negative correlation between YAP signature activation and HBV transcript levels. Intraperitoneal administration of YAP small molecule agonist potently controls HBV in male mouse models. These findings unveil a mechanism that involves the mechanical environment of hepatocytes and YAP to clear hepatotropic viral infection in the liver, providing new perspectives for HBV cure studies and antiviral development.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Hepatocitos , Hígado , Replicación Viral , Virus de la Hepatitis B/fisiología , Virus de la Hepatitis B/efectos de los fármacos , Animales , Hígado/virología , Hígado/metabolismo , Masculino , Humanos , Hepatocitos/virología , Hepatocitos/metabolismo , Ratones , Replicación Viral/efectos de los fármacos , Hepatitis B/virología , Hepatitis B/tratamiento farmacológico , Proteínas Señalizadoras YAP/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Mecanotransducción Celular , Antivirales/farmacología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Células Hep G2 , Modelos Animales de Enfermedad
2.
Polymers (Basel) ; 16(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39274060

RESUMEN

With the increasing shortage of water resources and the aggravation of water pollution, solar-driven interfacial steam generation (SISG) technology has garnered considerable attention because of its low energy consumption, simple operation, and environmental friendliness. The popular multi-layer SISG evaporator is composed of two basic structures: a photothermal layer and a support layer. Herein, the support layer underlies the photothermal layer and carries out thermal management, supports the photothermal layer, and transports water to the evaporation interface to improve the stability of the evaporator. While most research focuses on the photothermal layer, the support layer is typically viewed as a supporting object for the photothermal layer. This review focuses on the support layer, which is relatively neglected in evaporator development. It summarizes existing progress in the field of multi-layer interface evaporators, based on various polymers and biomaterials, along with their advantages and disadvantages. Specifically, mainly polymer-based support layers are reviewed, including polymer foams, gels, and their corresponding functional materials, while biomaterial support layers, including natural plants, carbonized biomaterials, and other innovation biomaterials are not. Additionally, the corresponding structure design strategies for the support layer were also involved. It was found that the selection and optimal design of the substrate also played an important role in the efficient operation of the whole steam generation system. Their evolution and refinement are vital for advancing the sustainability and effectiveness of interfacial evaporation technology. The corresponding potential future research direction and application prospects of support layer materials are carefully presented to enable effective responses to global water challenges.

3.
Rev Sci Instrum ; 95(9)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39320139

RESUMEN

Phase-shifting speckle interferometry could achieve full-field deformation measurement of rough surfaces. To meet the dynamic requirement and further improve the accuracy, a two-step synchronous phase-shifting measurement system is established based on the polarization-sensitive phase modulation ability of a liquid crystal spatial light modulator; by multiplexing the reference wavefront, an accurate phase shift is generated between two independent recording channels, and a common-path self-reference vortex interference structure is built for precise spatial registration. Meanwhile, according to the speckle statistical principle, a novel two-frame phase-shifting algorithm as well as a two-step spatial registration strategy is presented to strengthen the robustness of intensity and position differences caused by spatial-multiplexing; thereby, accurate transient deformation can be directly obtained from phase-shifting speckle interferograms recorded before and after deformation. The effectiveness and accuracy of the proposal are validated from the out-of-plane deformation measurement experiment by comparing with the traditional two-step and four-step phase-shifting methods. The dynamic ability is exhibited through reconstructing mechanical and thermal deformations across various application scenarios.

4.
Cell Rep Methods ; 4(9): 100843, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39216483

RESUMEN

Dual-attribute immune cells possess advantageous features of cytotoxic T cells and natural killer (NK) cells and hold promise for advancing immunotherapy. Dual-attribute cell types such as invariant natural killer T cells, induced T-to-NK cells, and cytokine-induced killer cells have demonstrated efficacy and safety in preclinical and clinical studies. However, their limited availability hinders their widespread application. Human pluripotent stem cells (hPSCs) offer an ideal source. Here, we generate dual-attribute induced T-NK (iTNK) cells from hPSCs, expressing markers of both cytotoxic T and NK cells. Single-cell RNA and T cell receptor (TCR) sequencing analyses reveal that iTNK cells expressed signature genes associated with both NK and T cells and displayed a diverse TCR repertoire. iTNK cells release cytotoxic mediators, exert cytotoxicity against diverse tumor cell lines, and inhibit tumor growth in vivo. By harnessing adaptive and innate immune responses, hPSC-derived iTNK cells offer promising strategies for cancer immunotherapy.


Asunto(s)
Inmunoterapia , Células Asesinas Naturales , Neoplasias , Humanos , Células Asesinas Naturales/inmunología , Inmunoterapia/métodos , Neoplasias/terapia , Neoplasias/inmunología , Animales , Ratones , Células Madre Pluripotentes/inmunología , Linfocitos T Citotóxicos/inmunología , Línea Celular Tumoral , Receptores de Antígenos de Linfocitos T/inmunología , Diferenciación Celular/inmunología
5.
Plants (Basel) ; 13(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39204772

RESUMEN

Cyclobalanopsis gilva, a valuable timber species in China, holds significant importance for understanding the constraints imposed by climate change on the dynamic geographic distribution of tree species. This study utilized the MaxEnt maximum entropy model to reconstruct the migratory dynamics of C. gilva geographical distribution since the Last Glacial Maximum. The objective was to comprehend the restrictive mechanisms of environmental factors on its potential geographical distribution, aiming to provide insights for mid-to-long-term afforestation planning of C. gilva. The optimized MaxEnt model exhibited a significantly high predictive accuracy, with an average AUC value of 0.949 ± 0.004 for the modern suitable habitat model of C. gilva. The total suitable habitat area for C. gilva in contemporary times was 143.05 × 104 km2, with a highly suitable habitat area of 3.14 × 104 km2. The contemporary suitable habitat was primarily located in the southeastern regions of China, while the highly suitable habitat was concentrated in eastern Fujian and central-eastern Taiwan. Bioclimatic variables such as mean diurnal range (Bio2), min temperature of coldest month (Bio6), precipitation of driest quarter (Bio17), and precipitation of driest month (Bio14) predominantly influenced the modern geographic distribution pattern of C. gilva, with temperature factors playing a leading role. With global climate warming, there is a risk of fragmentation or even loss of suitable habitat for C. gilva by 2050 and 2090. Therefore, the findings of this study can significantly contribute to initiating a habitat conservation campaign for this species.

6.
Opt Express ; 32(11): 18800-18811, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38859029

RESUMEN

In sixth generation (6G) communications, terahertz (THz) communication is one of the most important technologies in the future due to its ultra-bandwidth, where hybrid beamforming has been widely used to solve the severe transmission attenuation in the THz band. However, the use of frequency-flat phase shifters in hybrid beamforming leads to the beam split effect. To solve the beam split influence, we propose a novel optical true time delay compensation network (OTTDCN)-based phase precoding structure with low power consumption. In the proposed scheme, the OTTDCN pre-generates multiple beam compensation modes to achieve phase compensation for different frequencies. As a result, the compensated beams can be reoriented toward the target direction at different frequencies. Moreover, a low-complexity beam compensation mode-based hybrid precoding algorithm is proposed, where the selection of the optimal beam compensation modes used for all radio-frequency (RF) chains with finite beam compensation modes is considered. The results show that the OTTDCN-based phase precoding scheme can effectively alleviate the beam split effect with low power consumption and achieve near-optimal performance.

7.
Environ Sci Pollut Res Int ; 31(25): 37010-37019, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38760599

RESUMEN

Studies identifying the relative importance of multiple ecological processes in macroinvertebrate communities in urban lakes at a basin scale are rare. In this study, 14 urban lakes in the Taihu Lake Basin were selected to explore the relative importance of environmental filtering and spatial processes in the assembly of macroinvertebrate communities. Our findings revealed significant spatiotemporal variations in macroinvertebrate communities, both between lakes and across seasons. We found that environmental filtering exerted a greater influence on taxonomic total beta diversity and its individual components (species turnover and nestedness) compared to spatial processes. Key environmental variables such as water depth, water temperature, total dissolved solids, chlorophyll a, and lake surface area were found to be crucial in shaping macroinvertebrate communities within these urban lakes. The observed high spatial heterogeneity in environmental conditions, along with intermediate basin areas, good connectivity and short distances between lakes, and the high dispersal ability of dominant taxa, likely contributed to the dominance of environmental filtering in macroinvertebrate community assembly. Our study contributes to a better understanding of the underlying mechanisms governing macroinvertebrate community assembly in urban lakes, thereby providing valuable insights for studies on community ecology and water environmental protection in urban lakes.


Asunto(s)
Monitoreo del Ambiente , Invertebrados , Lagos , China , Animales , Ecosistema , Biodiversidad
8.
BMC Plant Biol ; 24(1): 351, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38684962

RESUMEN

BACKGROUND: Rose (Rosa hybrida) is a globally recognized ornamental plant whose growth and distribution are strongly limited by drought stress. The role of Mediator, a multiprotein complex crucial for RNA polymerase II-driven transcription, has been elucidated in drought stress responses in plants. However, its physiological function and regulatory mechanism in horticultural crop species remain elusive. RESULTS: In this study, we identified a Tail module subunit of Mediator, RhMED15a-like, in rose. Drought stress, as well as treatment with methyl jasmonate (MeJA) and abscisic acid (ABA), significantly suppressed the transcript level of RhMED15a-like. Overexpressing RhMED15a-like markedly bolstered the osmotic stress tolerance of Arabidopsis, as evidenced by increased germination rate, root length, and fresh weight. In contrast, the silencing of RhMED15a-like through virus induced gene silencing in rose resulted in elevated malondialdehyde accumulation, exacerbated leaf wilting, reduced survival rate, and downregulated expression of drought-responsive genes during drought stress. Additionally, using RNA-seq, we identified 972 differentially expressed genes (DEGs) between tobacco rattle virus (TRV)-RhMED15a-like plants and TRV controls. Gene Ontology (GO) analysis revealed that some DEGs were predominantly associated with terms related to the oxidative stress response, such as 'response to reactive oxygen species' and 'peroxisome'. Furthermore, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment highlighted pathways related to 'plant hormone signal transduction', in which the majority of DEGs in the jasmonate (JA) and ABA signalling pathways were induced in TRV-RhMED15a-like plants. CONCLUSION: Our findings underscore the pivotal role of the Mediator subunit RhMED15a-like in the ability of rose to withstand drought stress, probably by controlling the transcript levels of drought-responsive genes and signalling pathway elements of stress-related hormones, providing a solid foundation for future research into the molecular mechanisms underlying drought tolerance in rose.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Virus de Plantas , Rosa , Rosa/genética , Rosa/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ciclopentanos/metabolismo , Ciclopentanos/farmacología , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Estrés Fisiológico/genética , Arabidopsis/genética , Arabidopsis/fisiología , Acetatos/farmacología , Plantas Modificadas Genéticamente
9.
J Mater Chem B ; 12(17): 4063-4079, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38572575

RESUMEN

DNA methylation is the process by which specific bases on a DNA sequence acquire methyl groups under the catalytic action of DNA methyltransferases (DNMT). Abnormal changes in the function of DNMT are important markers for cancers and other diseases; therefore, the detection of DNMT and the selection of its inhibitors are critical to biomedical research and clinical practice. DNA molecules can undergo intermolecular assembly to produce functional aggregates because of their inherently stable physical and chemical properties and unique structures. Conventional DNMT detection methods are cumbersome and complicated processes; therefore, it is necessary to develop biosensing technology based on the assembly of DNA nanostructures to achieve rapid analysis, simple operation, and high sensitivity. The design of the relevant program has been employed in life science, anticancer drug screening, and clinical diagnostics. In this review, we explore how DNA assembly, including 2D techniques like hybridization chain reaction (HCR), rolling circle amplification (RCA), catalytic hairpin assembly (CHA), and exponential isothermal amplified strand displacement reaction (EXPAR), as well as 3D structures such as DNA tetrahedra, G-quadruplexes, DNA hydrogels, and DNA origami, enhances DNMT detection. We highlight the benefits of these DNA nanostructure-based biosensing technologies for clinical use and critically examine the challenges of standardizing these methods. We aim to provide reference values for the application of these techniques in DNMT analysis and early cancer diagnosis and treatment, and to alert researchers to challenges in clinical application.


Asunto(s)
Técnicas Biosensibles , ADN , Nanoestructuras , Nanotecnología , Técnicas Biosensibles/métodos , Humanos , ADN/química , ADN/metabolismo , Nanoestructuras/química , Metilación de ADN , Metilasas de Modificación del ADN/metabolismo , Metilasas de Modificación del ADN/análisis
10.
BMC Anesthesiol ; 24(1): 126, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565990

RESUMEN

BACKGROUND: The comparison between sedation and general anesthesia (GA) in terms of all-cause mortality remains a subject of ongoing debate. The primary objective of our study was to investigate the impact of GA and sedation on all-cause mortality in order to provide clarity on this controversial topic. METHODS: A systematic review and meta-analysis were conducted, incorporating cohort studies and RCTs about postoperative all-cause mortality. Comprehensive searches were performed in the PubMed, EMBASE, and Cochrane Library databases, with the search period extending until February 28, 2023. Two independent reviewers extracted the relevant information, including the number of deaths, survivals, and risk effect values at various time points following surgery, and these data were subsequently pooled and analyzed using a random effects model. RESULTS: A total of 58 studies were included in the analysis, with a majority focusing on endovascular surgery. The findings of our analysis indicated that, overall, and in most subgroup analyses, sedation exhibited superiority over GA in terms of in-hospital and 30-day mortality. However, no significant difference was observed in subgroup analyses specific to cerebrovascular surgery. About 90-day mortality, the majority of studies centered around cerebrovascular surgery. Although the overall pooled results showed a difference between sedation and GA, no distinction was observed between the pooled ORs and the subgroup analyses based on RCTs and matched cohort studies. For one-year all-cause mortality, all included studies focused on cardiac and macrovascular surgery. No difference was found between the HRs and the results derived from RCTs and matched cohort studies. CONCLUSIONS: The results suggested a potential superiority of sedation over GA, particularly in the context of cardiac and macrovascular surgery, mitigating the risk of in-hospital and 30-day death. However, for the longer postoperative periods, this difference remains uncertain. TRIAL REGISTRATION: PROSPERO CRD42023399151; registered 24 February 2023.


Asunto(s)
Anestesia General , Humanos , Anestesia General/métodos , Anestesia General/mortalidad , Mortalidad Hospitalaria , Procedimientos Endovasculares/métodos , Sedación Consciente/métodos , Sedación Consciente/mortalidad , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos
11.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557883

RESUMEN

Quantitative phase imaging (QPI) provides 3D structural and morphological information for label free living cells. Unfortunately, this quantitative phase information cannot meet doctors' diagnostic requirements of the clinical "gold standard," which displays stained cells' pathological states based on 2D color features. To make QPI results satisfy the clinical "gold standard," the virtual staining method by QPI for label free lymphocytes based on self-supervised iteration Cycle-Consistent Adversarial Networks (CycleGANs) is proposed herein. The 3D phase information of QPI is, therefore, trained and transferred to a kind of 2D "virtual staining" image that is well in agreement with "gold standard" results. To solve the problem that unstained QPI and stained "gold standard" results cannot be obtained for the same label free living cell, the self-supervised iteration for the CycleGAN deep learning algorithm is designed to obtain a trained stained result as the ground truth for error evaluation. The structural similarity index of our virtual staining experimental results for 8756 lymphocytes is 0.86. Lymphocytes' area errors after converting to 2D virtual stained results from 3D phase information are less than 3.59%. The mean error of the nuclear to cytoplasmic ratio is 2.69%, and the color deviation from the "gold standard" is less than 6.67%.


Asunto(s)
Algoritmos , Imágenes de Fase Cuantitativa , Coloración y Etiquetado
12.
Opt Express ; 32(7): 11737-11750, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571014

RESUMEN

This paper provides an extensive discussion of a complex amplitude-based dynamic three-dimensional deformation measurement method, in which the phase and amplitude of the speckle field are used for out-of-plane and in-plane deformation calculation respectively. By determining the optimal polarization states of the speckle field and reference field from the comprehensive analysis of measurement mathematical model in the principle of polarization multiplexing, the 3-step phase-shifting interferograms and one speckle gram can be directly recorded by a polarization camera in a single shot. The out-of-plane deformation would be recovered from the subtraction of speckle phases that are demodulated by a special least square algorithm; speckle gram with improved quality is offered for correlation computation to obtain in-plane deformation. The advancement and significance of the optimized strategy are intuitively demonstrated by comparing the measurement accuracy under different combinations of polarization states. Finally, the dynamic thermal deformation experiment reveals the potential in practical real-time applications.

13.
Sensors (Basel) ; 24(6)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38544229

RESUMEN

This study addresses the ongoing challenge for learning-based methods to achieve accurate object detection in foggy conditions. In response to the scarcity of foggy traffic image datasets, we propose a foggy weather simulation algorithm based on monocular depth estimation. The algorithm involves a multi-step process: a self-supervised monocular depth estimation network generates a relative depth map and then applies dense geometric constraints for scale recovery to derive an absolute depth map. Subsequently, the visibility of the simulated image is defined to generate a transmittance map. The dark channel map is then used to distinguish sky regions and estimate atmospheric light values. Finally, the atmospheric scattering model is used to generate fog simulation images under specified visibility conditions. Experimental results show that more than 90% of fog images have AuthESI values of less than 2, which indicates that their non-structural similarity (NSS) characteristics are very close to those of natural fog. The proposed fog simulation method is able to convert clear images in natural environments, providing a solution to the problem of lack of foggy image datasets and incomplete visibility data.

14.
Cancers (Basel) ; 15(22)2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-38001569

RESUMEN

Hepatocellular carcinoma (HCC) develops through multiple mechanisms. While recent studies have shown the presence of extrachromosomal circular DNA (eccDNA) in most cancer types, the eccDNA expression pattern and its association with HCC remain obscure. We aimed to investigate this problem. The genome-wide eccDNA profiles of eight paired HCC and adjacent non-tumor tissue samples were comprehensively elucidated based on Circle-seq, and they were further cross-analyzed with the RNA sequencing data to determine the association between eccDNA expression and transcriptome dysregulation. A total of 60,423 unique eccDNA types were identified. Most of the detected eccDNAs were smaller than 1 kb, with a length up to 182,363 bp and a mean sizes of 674 bp (non-tumor) and 813 bp (tumor), showing a greater association with gene-rich rather than with gene-poor regions. Although there was no statistical difference in length and chromosome distribution, the eccDNA patterns between HCC and adjacent non-tumor tissues showed significant differences at both the chromosomal and single gene levels. Five of the eight HCC tissues showed significantly higher amounts of chromosome 22-derived eccDNA expression compared to the non-tumor tissue. Furthermore, two genes, SLC16A3 and BAIAP2L2, with a higher transcription level in tumor tissues, were related to eccDNAs exclusively detected in three HCC samples and were negatively associated with survival rates in HCC cohorts from public databases. These results indicate the existence and massive heterogeneity of eccDNAs in HCC and adjacent liver tissues, and suggest their potential association with dysregulated gene expression.

15.
J Agric Food Chem ; 71(42): 15745-15753, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37816159

RESUMEN

Not only do flavan-3-ols participate in the formation of chromogenic oxidation products such as theaflavins, but chlorogenic acid (3-caffeoylquinic acid, CQA) is also involved in the enzymatic oxidation during black tea processing. The critical oxidation product of CQA and (-)-epigallocatechin (EGC) were identified as an adduct containing benzobicyclo[3.2.2]nonenone structure, which was named as the dichlorogeniccatechin (DCGC) oligomer. It was composed of two molecules of CQA and one molecule of EGC. The effects of the initial reactant ratio and reaction time on the generation of DCGC were also analyzed. A high proportion of CQA promoted the production of DCGC, but a high proportion of EGC inhibited the DCGC formation. In addition, the content of DCGC in Keemun black tea during processing was determined. The content of DCGC highly increased after withering but decreased after drying. This study provides a new perspective for the investigation of other oxidation oligomers in black tea.


Asunto(s)
Camellia sinensis , Catequina , Té/química , Ácido Clorogénico , Catequina/química , Camellia sinensis/química , Oxidación-Reducción
16.
Opt Express ; 31(21): 33830-33841, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37859154

RESUMEN

This paper proposes a flexible and accurate dynamic quantitative phase imaging (QPI) method using single-shot transport of intensity equation (TIE) phase retrieval achieved by division of focal plane (DoFP) polarization imaging technique. By exploiting the polarization property of the liquid crystal spatial light modulator (LC-SLM), two intensity images of different defocus distances contained in orthogonal polarization directions can be generated simultaneously. Then, with the help of the DoFP polarization imaging, these images can be captured with single exposure, enabling accurate dynamic QPI by solving the TIE. In addition, our approach gains great flexibility in defocus distance adjustment by adjusting the pattern loaded on the LC-SLM. Experiments on microlens array, phase plate, and living human gastric cancer cells demonstrate the accuracy, flexibility, and dynamic measurement performance for various objects. The proposed method provides a simple, flexible, and accurate approach for real-time QPI without sacrificing the field of view.

17.
Opt Express ; 31(16): 25635-25647, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37710445

RESUMEN

We propose a fast and robust method for calibrating Spatial Light Modulators (SLMs) based on polarization phase-shifting interferometry. Our method effectively calibrates the SLM by addressing both the static aberration and nonlinear phase response, utilizing specially designed gray images loaded sequentially onto the SLM. Notably, we introduce a novel kinoform that effectively eliminates the influence of tilt phase shift between two shots of the polarization camera. This results in a highly accurate phase aberration map and phase modulation curve with exceptional stability, making it an ideal method to calibrate the SLM with exceptional efficiency and precision in real applications.

18.
Anal Chim Acta ; 1271: 341432, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37328254

RESUMEN

Tetrahedral DNA nanostructure (TDN), as a classical bionanomaterial, which not only has excellent structural stability and rigidity, but also possesses high programmability due to strict base-pairs complementation, is widely used in various biosensing and bioanalysis fields. In this study, we first constructed a novel biosensor based on Uracil DNA glycosylase (UDG) -triggered collapse of TDN and terminal deoxynucleotidyl transferase (TDT)-induced insertion of copper nanoparticles (CuNPs) for fluorescence and visual analysis of UDG activity. In the presence of the target enzyme UDG, the uracil base modified on the TDN were specifically identified and removed to produce an abasic site (AP site). Endonuclease IV (Endo.IV) could cleave the AP site, making the TDN collapse and generating 3'-hydroxy (3'-OH), which were then elongated under the assistance of TDT to produce poly (T) sequences. Finally, Copper (II) sulfate (Cu2+) and l-Ascorbic acid (AA) were added to form CuNPs using poly (T) sequences as templates (T-CuNPs), resulting in a strong fluorescence signal. This method exhibited good selectivity and high sensitivity with a detection limit of 8.6 × 10-5 U/mL. Moreover, the strategy has been successfully applied to the screening of UDG inhibitors and the detection of UDG activity in complex cell lysates, which means that it has promising applications in clinical diagnosis and biomedical research.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , ADN Nucleotidilexotransferasa , Uracil-ADN Glicosidasa/análisis , Cobre , Límite de Detección , ADN/química , ADN Polimerasa Dirigida por ADN , Técnicas Biosensibles/métodos
19.
Opt Lett ; 48(9): 2329-2332, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37126266

RESUMEN

An accurate dynamic 3D deformation measurement method realized by the combination of phase-shifting speckle interferometry and speckle correlation is proposed. By converting the speckle field and the reference field into a circular polarized and linear polarized state, the three-step phase-shifting speckle interferograms and one specklegram were recorded directly and simultaneously within a single image by using a polarization camera. Then, the out-of-plane deformation was demodulated from the synchronous phase-shifting fringe patterns, and the in-plane deformation was measured by performing correlation calculations by using specklegrams with the effect of the reference field ignored. Thus, the full-field 3D deformation was obtained precisely. Experimental results demonstrated the accuracy and dynamic measurement ability of the proposed method, which is compact and feasible for actual dynamic scenes.

20.
Sci Total Environ ; 885: 163844, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37142005

RESUMEN

A field experiment was conducted to investigate the effectiveness and mechanisms of foliar spraying of transpiration inhibitor (TI) and different amounts of rhamnolipid (Rh) on the Cd content in rice grain. The contact angle of TI on the rice leaves was significantly reduced when it was combined with one critical micelle concentration of Rh. The Cd concentration in the rice grain in the presence of TI, TI + 0.5Rh, TI + 1Rh, and TI + 2Rh significantly decreased by 30.8 %, 41.7 %, 49.4 %, and 37.7 % respectively, compared with the control treatment. Specifically, the Cd content with TI + 1Rh was as low as 0.182 ± 0.009 mg/kg, which meets the national food safety requirements (< 0.2 mg/kg). The rice yield and plant biomass of TI + 1Rh were highest compared to the other treatments, possibly because of the alleviation of oxidative stress due to Cd. The hydroxyl and carboxyl concentrations in the soluble components in the leaf cells for the TI + 1Rh treatment were the highest compared to the other treatments. Our results demonstrated that the foliar spraying of TI + 1Rh is an efficient method to reduce Cd accumulation in rice grain. It holds potential for the future development of safe food production in soils polluted with Cd.


Asunto(s)
Oryza , Contaminantes del Suelo , Cadmio/toxicidad , Cadmio/análisis , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Suelo
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