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We have previously reported that advanced glycation end products activated Rho-associated protein kinase and p38 mitogen–activated protein kinase, causing endothelial hyperpermeability. However, the mechanisms involved were not fully clarified. Here, we explored the role of myosin light chain kinase in advanced glycation end product–induced endothelial hyperpermeability. Myosin light chain phosphorylation significantly increased by advanced glycation end products in endothelial cells in a time- and dose-dependent manner, indicating that myosin light chain phosphorylation is involved in the advanced glycation end product pathway. Advanced glycation end products also induced myosin phosphatase–targeting subunit 1 phosphorylation, and small interfering RNA knockdown of the receptor for advanced glycation end products, or blocking myosin light chain kinase with its inhibitor, ML-7, or small interfering RNA abated advanced glycation end product–induced myosin light chain phosphorylation. Advanced glycation end product–induced F-actin rearrangement and endothelial hyperpermeability were also diminished by inhibition of receptor for advanced glycation end product or myosin light chain kinase signalling. Moreover, inhibiting myosin light chain kinase with ML-7 or blocking receptor for advanced glycation end product with its neutralizing antibody attenuated advanced glycation end product–induced microvascular hyperpermeability. Our findings suggest a novel role for myosin light chain and myosin light chain kinase in advanced glycation end product–induced endothelial hyperpermeability. [ABSTRACT FROM AUTHOR]

Nucleic acid aptamers are small sequences of DNA made via in vitro selection techniques to bind targets with high affinity and specificity. The term aptamer derives from the Latin, aptus, meaning “to fit”, emphasizing the lock-and-key relationship between aptamers and their binding targets. In 2004, aptamers began to attract researchers’ attention as new binding elements for biosensors (i.e. aptasensors). Their advantages over other sensors include a diverse range of possible target molecules, high target affinity, simple synthesis, and ability to form Watson–Crick base pairs. These attributes create an enormous array of possible sensing applications and target molecules, spanning nearly all detection methods and readout techniques. In particular, aptamers provide an opportunity for designing “label-free” sensors, meaning sensors that do not require covalently labeling a signal probe to either the analyte or the recognition element (here, the aptamer). “Label-free” systems previously could only analyze large molecules using a few readout techniques, such as when employing the other recognition elements like antibodies. “Label-free” methods are one of the most effective and promising strategies for faster, simpler, and more convenient detection, since they avoid the expensive and tedious labeling process and challenging labeling reactions, while retaining the highest degree of activity and affinity for the recognition element. “Label-free” sensors are one of the most promising future biosensors. [ABSTRACT FROM AUTHOR]

Polystyrene (PS), a polymer material renowned for its notable optical and mechanical properties, as well as low cost and ease of processing, stands as one of optimal candidate for flexible electrode substrate materials. However, prevalent modification techniques such as lithography, electron beam evaporation, and plasma etching all entail the requirement for specialized equipment and precise operation, thereby significantly elevating the technical barrier. In this study, we introduce a chemical plating method to fabricate a gold film electrode, coupled with prussian blue (PB) and glucose oxidase (GOx), for the development of a glucose electrochemical biosensor. This process offers simplicity, cost‐effectiveness, and feasibility under regular experimental conditions. The electrode surface is covered with numerous gold nanoparticles, effectively augmenting the actual electrode area and enhancing electron transfer efficiency. Remarkably, without the addition of sensitizing agents, the biosensor achieves highly sensitive glucose detection. The proposed biosensor exhibits a broad linear relationship in the concentration range of 0.005–1 mM, with a detection limit of 4.4 μM. Moreover, it exhibits favorable performance in detecting glucose levels in sweat samples, showcasing promising prospects for personal healthcare diagnostics. [ABSTRACT FROM AUTHOR]

Heterometallic supramolecules, known for their unique synergistic effects, have shown broad applications in photochemistry, host‐guest chemistry, and catalysis. However, there are great challenges to precisely construct heterometallic supramolecules rather than a statistical mixture, due to the limited metal‐ion selectivity of coordination units. In particular, heterometallic architectures precisely encoded with different metal ions usually fail to form in a one‐pot method when only one type of coordinated motif exists due to its poor metal‐ion selectivity. Herein, we propose an effective intramolecular cation‐π (ICπ) strategy and successfully constructed the heterometallic supramolecule Zn2Cu4L34 by the one‐pot self‐assembly of tritopic terpyridyl ligand L3 with Zn(II) and Cu(II), following a clear self‐assembly mechanism in which only thermodynamic dimers ZnL12 and Cu2L22 were constructed with model ligands L1, L2, Zn(II) and Cu(II) with perfect self‐sorting and an ultra‐high metal‐selectivity feature. The successful construction of the heterometallic supramolecule Zn2Cu4L34, in which the definite sequence of metal ions Zn(II) and Cu(II) is encoded in the one‐pot method, will offer a novel approach to precisely construct heterometallic architectures. [ABSTRACT FROM AUTHOR]

In order to realize portable pathogen diagnostics with easier quantitation, digitization and integration, we develop a ready‐to‐use electrochemical sensing strategy (Iso‐E‐Codelock) for real‐time detection of isothermal nucleic acid amplification. Bridged by a branched DNA as codelock, the isothermal amplicon is transduced into increased current of an electrochemical probe, holding multiple advantages of high sensitivity, high selectivity, signal‐on response, "zero" background and one‐pot operation. Through a self‐designed portable instrument (BioAlex PHE−T), the detection can be implemented on a multichannel microchip and output real‐time amplification curves just like an expensive commercial PCR machine. The microchip is a rebuilding‐free and disposable component. The branch codelock probe can be customized for different targets and designs. Such high performance and flexibility have been demonstrated utilizing four virus (SARS‐CoV‐2, African swine fever, FluA and FluB) genes as targets, and two branch (3‐way and 4‐way) DNAs as codelock probes. [ABSTRACT FROM AUTHOR]

Through controlling the ssDNA product length of rolling circle amplification with AcyNTP, here we develop a nanopore signal enhancement strategy (STSS), which can successfully transfer the short oligonucleotide targets into long ssDNAs with appropriate lengths that can generate significant translocation currents. By labelling the RCA product with tags such as tetrahedral structures and isothermal amplicons, the resolution, signal specificity, and target range of the STSS can be further extended. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The development of accurate, rapid and practical electrochemical sensing technology for antibiotic detection has an important application prospect in many fields such as food safety, environmental monitoring, medical and health care. In this research, kanamycin specific DNA aptamer and its partially complementary short chain were self‐assembled onto the surface of an integrated portable plastic gold electrode (PGE) by Au—S bond, and a simple kanamycin electrochemical biosensor interface was constructed. At the same time, the epoxy resin channel layer was designed, and the auxiliary instrument was set up independently in the laboratory, which could help to measure and analyze eight groups of samples automatically in turn. The quantitative analysis results showed that in 20 min, the sensor had a good linear relationship between the peak current change of square wave voltammetry and the negative logarithm of kanamycin concentration when kanamycin concentration was in the range of 1—1000 μmol/L, and the detection limit could reach 0.40 μmol/L. In addition, the discrimination could be achieved within 5 min in the real‐time analysis mode. The sensor had a simple construction method, good selectivity and stability, and could be used for rapid or real‐time detection of kanamycin residues in actual water samples, which provided a new direction for the practical detection of kanamycin in environmental water samples. [ABSTRACT FROM AUTHOR]

Recent years, molecular detection technology has been playing an unprecedentedly important role in disease prevention and public health. Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) systems such as CRISPR/Cas12a and CRISPR/Cas13a, have been increasingly used in the detection of nucleic acid molecules because of its collateral cleavage ability in recent years. Herein, we develop a universal CRISPR/Cas12a‐assisted methodology based on a nucleic acid duplex switch structure that can distinguish different categories of targets, such as DNA, RNA and small molecules. It is worth noting that for nucleic acid detection, this method can significantly identify single base substitutions with high specificity, compared with other Cas12a‐assisted biosensing systems. The experimental results suggest that this method has great specificity for different targets, promising to be applied to rapid molecular diagnosis. [ABSTRACT FROM AUTHOR]

Nanopore sensing is highly promising in single molecular analysis but their broad applications have been challenged by the limited strategies that can transduce a target‐of‐interest into a specific and anti‐false/inference signal, especially for solid‐state nanopores with relatively lower resolution and higher noise. Here we report a high‐resolution signal‐production concept named target‐induced duplex polymerization strategy (DPS). Through linking the same or different duplex substrates (DSs) with a special linker (L) and an optional structure tag (ST), the DPS can generate target‐specific DS polymers with highly controllable duration times, duration intervals and even distinguished secondary tagging currents. Experimentally, DPS mono‐polymerization of single DS and co‐polymerization of multiple DSs has verified the duration time of a DPS product is the sum of those for each DS monomer. Tetrahedron‐DNA structures with different sizes are used as the STs to provide needle‐like secondary peaks for further resolution enhancement and multiplex assay. With these examples DPS represents a general, programmable and advanced strategy that may simultaneously provide size‐amplification, concentration amplification, and signal‐specificity for molecular recognition. It is also promisingly in various applications regarding to single molecular investigation, such as polymerization degree, structure/side chain conformation, programmable multiplex decoding and information index. [ABSTRACT FROM AUTHOR]

Nucleic acid testing technology has made considerable progress in the last few years. However, there are still many challenges in the clinical application of multiple nucleic acid assays, such as how to ensure accurate results, increase speed and decrease cost. Herein, a three-way junction structure has been introduced to specifically translate analytes of loop-mediated isothermal amplification to a catalytic hairpin assembly. For different analyses, a well-optimized nucleic acid circuit can be directly applied to detection, through only one-component replacement, which only not avoids duplicate sequence design but also saves detection cost. Thanks to this design, multiple and logical analysis can be easily realized in a single reaction with ultra-high sensitivity and selectivity. In this paper, Mycoplasma pneumoniae and Streptococcus pneumoniae can be clearly distinguished from the clinical mixed sample with negative control or one analyte in one tube single fluorescence channel. The fair experimental results of actual clinical samples provide a strong support for the possibility of clinical application of this methodology. [ABSTRACT FROM AUTHOR]

Particular interest has been focused on modulation of solid‐state charge transport (CT) in DNA. Nevertheless, it remains challenging to do so in a sensitive and predictive manner due to the lack of a definite relationship between DNA base pair stacking and DNA CT. The challenges can be mainly attributed to the ill‐defined systems, which may lead to ambiguous and even contradictory conclusions. Here, we use DNA hairpins to construct the well‐defined self‐assembled monolayers. We reveal nearly positive‐linear correlations between DNA conformation and CT in the DNA hairpins regulated with metal ion chelation and DNA sequence. The correlations have been confirmed by the solid‐state current‐voltage characteristics and circular dichroism in solution. The enhanced CT via metal ion chelated DNA hairpins is mainly from the improved DNA energy coupling to electrodes, not the almost unchanged energy barrier when Hg ion‐induced DNA conformational switches toward the canonical B‐form. [ABSTRACT FROM AUTHOR]

Sensitive, rapid and low‐cost nucleic acid detection is critical for controlling infectious pathogens. Here, we develop a ready‐to‐use and multimodal detection based on a rebuilding‐free, ultrasensitive and selective strategy named dual hairpin ligation‐induced isothermal amplification pro (DHLApro). Taking influenza A, influenza B, MERS‐CoV, SARS‐CoV‐2 as model targets, we demonstrate DHLApro provides ≈zM level ultra‐sensitivity, being equaling to 0.45 copy/μL in original sample. By simply changing the recognition module, a set of DHLApro components can be applied to a new target without performance loss. Moreover, DHLApro innovatively allows flexible logic/multiplex assay using one set of primer, for example, the "N pathogens‐in‐1" OR gate screening and accurate multi‐channel multiplex assay. Compared with traditional methods, the cost of this logic/multiplex assay has been largely reduced and the cross‐interference between the multiple primer sets is also avoided. [ABSTRACT FROM AUTHOR]

The rapid development of spatial transcriptomics allows the measurement of RNA abundance at a high spatial resolution, making it possible to simultaneously profile gene expression, spatial locations of cells or spots, and the corresponding hematoxylin and eosin-stained histology images. It turns promising to predict gene expression from histology images that are relatively easy and cheap to obtain. For this purpose, several methods are devised, but they have not fully captured the internal relations of the 2D vision features or spatial dependency between spots. Here, we developed Hist2ST, a deep learning-based model to predict RNA-seq expression from histology images. Around each sequenced spot, the corresponding histology image is cropped into an image patch and fed into a convolutional module to extract 2D vision features. Meanwhile, the spatial relations with the whole image and neighbored patches are captured through Transformer and graph neural network modules, respectively. These learned features are then used to predict the gene expression by following the zero-inflated negative binomial distribution. To alleviate the impact by the small spatial transcriptomics data, a self-distillation mechanism is employed for efficient learning of the model. By comprehensive tests on cancer and normal datasets, Hist2ST was shown to outperform existing methods in terms of both gene expression prediction and spatial region identification. Further pathway analyses indicated that our model could reserve biological information. Thus, Hist2ST enables generating spatial transcriptomics data from histology images for elucidating molecular signatures of tissues. [ABSTRACT FROM AUTHOR]

Desirable biosensing assays need to be sensitive, specific, cost‐effective, instrument‐free, and versatile. Herein we report a new strategy termed CLIPON (CRISPR and Large DNA assembly Induced Pregnancy strips for signal‐ON detection) that can deliver these traits. CLIPON integrates a commercial pregnancy test strip (PTS) with four biological elements: the human chorionic gonadotropin (hCG), CRISPR‐Cas12a, crRNA and cauliflower‐like large‐sized DNA assemblies (CLD). CLIPON uses the Cas12a/crRNA complex both to recognize a target of interest and to release CLD‐bound hCG so that target presence can translate into a colorimetric signal on the PTS. We demonstrate the versatility of CLIPON through sensitive and specific detection of HPV genomic DNA, SARS‐CoV‐2 genomic RNA and adenosine. We also engineer a cell phone app and a hand‐held microchip to achieve signal quantification. CLIPON represents an attractive option for biosensing and point‐of‐care diagnostics. [ABSTRACT FROM AUTHOR]

Abstract: In this article, we reported a novel approach for in situ labeling and imaging HeLa cancer cells utilizing a bifunctional aptamer (AS1411) and its fluorescent ligand, protoporphyrin IX (PPIX). In the presence of potassium ion, AS1411 folded to G-quadruplex structure, binded fluorescent ligand (PPIX) with fluorescent enhancement, and targeted the nucleolin overexpressed by cancer cells. Consequently, bioimaging of cancer cells specifically were realized by laser scanning confocal microscope. The bioimaging strategy with AS1411–PPIX complex was capable to distinguish HeLa cancer cells from normal cells unambiguously, and fluorescence imaging of cancer cells was also realized in human serum. Moreover, the bioimaging method was very facile, effective and need not any covalent modification. These results illustrated that the useful approach can provide a novel clue for bioimaging based on non-covalent bifunctional aptamer in clinic diagnosis. [Copyright &y& Elsevier]