DNA-Programmed Four-Bit Quaternary Fluorescence Encoding (FLUCO) Enables 51-Colored Bioimaging Analysis.

Color encoding plays a crucial role in painting, digital photography, and spectral analysis. Achieving accurate, target-responsive color encoding at the molecular level has the potential to revolutionize scientific research and technological innovation, but significant challenges persist. Here, we propose a multibit DNA self-assembly system based on computer-aided design (CAD) technology, enabling accurate, target-responsive, amplified color encoding at the molecular level, termed fluorescence encoding (FLUCO). As a model, we establish a quaternary FLUCO system using four-bit DNA self-assembly, which can accurately encode 51 colors, presenting immense potential in applications such as spatial proteomic imaging and multitarget analysis. Notably, FLUCO enables the simultaneous imaging of multiple targets exceeding the limitations of channels using conventional imaging equipment, and marks the integration of computer science for molecular encoding and decoding. Overall, our work paves the way for target-responsive, controllable molecular encoding, facilitating spatial omics analysis, exfoliated cell analysis, and high-throughput liquid biopsy.

Proximity-Enhanced Functional Imaging Analysis of Engineered Tumors.

Functional imaging (FI) techniques have revolutionized tumor imaging by providing information on specific tumor functions, such as glycometabolism. However, tumor cells lack unique molecular characteristics at the molecular level and metabolic pathways, resulting in limited metabolic differences compared to normal cells and increased background signals from FI. To address this limitation, we developed a novel imaging technique termed proximity-enhanced functional imaging (PEFI) for accurate visualization of tumors. By using "two adjacent chemically labeled glycoproteins" as output signals, we significantly enhance the metabolic differences between tumor and normal cells by PEFI, thereby reducing the background signals for analysis and improving the accuracy of tumor functional imaging. Our results demonstrate that PEFI can accurately identify tumors at the cellular, tissue, and animal level, and has potential value in clinical identification and analysis of tumor cells and tissues, as well as in the guidance of clinical tumor resection surgery.

An Intelligent DNA Nanoreactor for Easy-to-Read In Vivo Tumor Imaging and Precise Therapy.

Nanomaterial-based in vivo tumor imaging and therapy have attracted extensive attention; however, they suffer from the unintelligent "always ON" or single-parameter responsive signal output, substantial off-target effects, and high cost. Therefore, achieving in vivo easy-to-read tumor imaging and precise therapy in a multi-parameter responsive and intelligent manner remains challenging. Herein, an intelligent DNA nanoreactor (iDNR) was constructed following the "AND" Boolean logic algorithm to address these issues. iDNR-mediated in situ deposition of photothermal substance polydopamine (PDA) can only be satisfied in tumor tissues with abundant membrane protein biomarkers "AND" hydrogen peroxide (H2 O2 ). Therefore, intelligent temperature-based in vivo easy-to-read tumor imaging is realized without expensive instrumentation, and its diagnostic performance matches with that of flow cytometry, and photoacoustic imaging. Moreover, precise photothermal therapy (PTT) of tumors could be achieved via intelligent heating of tumor tissues. The precise PTT of primary tumors in combination with immune checkpoint blockade (ICB) therapy suppresses the growth of distant tumors and inhibits tumor recurrence. Therefore, highly programmable iDNR is a powerful tool for intelligent biomedical applications.

Aptamer-based self-assembled nanomicelle enables efficient and targeted drug delivery.

Nucleic acid aptamer-based nanomicelles have great potential for nanomedicine and nanotechnology applications. However, amphiphilic aptamer micelles are known to be inherently unstable upon interaction with cell membranes in the physiological environment, thus potentially compromising their specific targeting against cancer cells. This flaw is addressed in the present work which reports a superstable micellar nanodelivery system as an amphiphilic copolymer self-assembled micelle composed of nucleic acid aptamer and polyvalent hydrophobic poly(maleic anhydride-alt-1-octadecene) (C18PMH). Using Ce6 as a drug model, these C18-aptamer micelles exhibit efficient tumor-targeting and -binding ability, facilitating the entry of Ce6 into targeted cells for photodynamic therapy. In addition, they can be loaded with other hydrophobic drugs and still demonstrate favorable therapeutic effects. As such, these C18-aptamer micelles can serve as a universal platform for loading multiple drugs, providing a safer and more effective solution for treating cancer.

Magnetism-Controllable Catalytic Activity of DNAzyme.

Controllable regulation of enzyme activity is an important prerequisite for the in-depth application of enzymes, especially in today's intelligent era. However, irreversible regulation and cumbersome operation make this goal difficult to achieve. Here, by adopting magnetism and a harmless, noncontact, and time- and space-controllable physical element, we developed a system that could conveniently and reversibly regulate the activity of DNAzyme. In this system, the strands of the DNAzyme could be stretched or folded by applying or removing a magnetic field. Thereby, the conformation-dependent endonuclease activity of the DNAzyme could be facilely switched between an "OFF" and "ON" state. This system provides a reusable platform for the control of enzyme catalytic activity through magnetism, which provides guidance for further application in some related scientific research, especially the regulation of the activity of conformation-dependent polymers (DNAzymes, aptamers, and peptides).

Computer-Aided Design of DNA Self-Limited Assembly for Relative Quantification of Membrane Proteins.

Immunofluorescence imaging of cells plays a vital role in biomedical research and clinical diagnosis. However, when it is applied to relative quantification of proteins, it suffers from insufficient fluorescence intensity or partial overexposure, resulting in inaccurate relative quantification. Herein, we report a computer-aided design of DNA self-limited assembly (CAD-SLA) technology and apply it for relative quantification of membrane proteins, a concept proposed for the first time. CAD-SLA can achieve exponential cascade signal amplification in one pot and terminate at any desired level. By conjugating CAD-SLA with immunofluorescence, in situ imaging of cell membrane proteins is achieved with a controllable amplification level. Besides, comprehensive fluorescence intensity information from fluorescent images can be obtained, accurately showing relative quantitative information. Slight protein expression differences previously indistinguishable by immunofluorescence or Western blotting can now be discriminated, making fluorescence imaging-based relative quantification a promising tool for membrane protein analysis. From the perspectives of both DNA self-assembly technology and immunofluorescence technology, this work has solved difficult problems and provided important reference for future development.

Single-Cell Analysis of Highly Metastatic Circulating Tumor Cells by Combining a Self-Folding Induced Release Reaction with a Cell Capture Microchip.

Nondestructive analysis of the single-cell molecular phenotype of circulating tumor cells (CTCs) is of great significance to the precise diagnosis and treatment of cancer but is also a huge challenge. To address this issue, here, we develop a facile analysis system that integrates CTCs' capture and molecular phenotype analysis. An isothermal nucleic acid amplification technique named self-folding induced release reaction (sFiR), which has high-efficiency signal amplification capabilities and can run under physiological conditions, is first developed to meet the high requirements for sensitivity and nondestructivity. By combining the sFiR with immune recognition and a single cell capture microchip, the molecular phenotype analysis of a single CTC is realized. As a model, nondestructive analysis of junction plakoglobin (JUP), an overexpressed membrane protein that is closely related to the metastasis of CTCs, is successfully achieved. Results reveal that this sFiR-based analysis system can clearly distinguish the expression of JUP in different cancer cell lines and can present quantitative information on the expression of JUP. Furthermore, the captured and analyzed CTCs maintain their basic physiological activity and can be used for drug sensitivity testing. Considering the excellent performance and ease of operation of the system, it can provide technical support for CTC-based cancer liquid biopsy and drug development.

Tetrahedral DNA Nanoconjugates for Simultaneous Measurement of Telomerase Activity and miRNA.

In this study, a tetrahedral DNA nanostructure was first self-assembled; this was then conjugated with gold nanoparticles (AuNPs) and carbon nanodots (CDs). The fabricated nanocomposites allow simultaneous analysis of telomerase activity and miRNA with dual fluorescence channels. By further introducing an iRGD peptide sequence, the nanoconjuates can be conveniently transferred inside living cells for in situ imaging. The analytical performances and anti-jamming capabilities are excellent. Meanwhile, the materials are highly biocompatible for intracellular applications. Therefore, the proposed biosystem shows great promise as a powerful tool for quantitative analysis of the dual biomarkers. The strategy can also be further exploited as a versatile platform for in situ detection of many other targets for early disease diagnosis.

pH-Based immunoassay: explosive generation of hydrogen ions through an immuno-triggered nucleic acid exponential amplification reaction.

In this work, we propose a novel concept and a proof-of-concept strategy for the fabrication of a pH-based immunoassay platform with a certain degree of universality and scalability to make it adaptable for different application scenarios. The immunoreactions for the target detection are converted to pH changes through an engineered and optimized isothermal nucleic acid amplification, named exponential amplification reaction (EXPAR). Thus, a variety of well-developed methods for pH analysis, e.g. pH indicators, pH-strips and pH meters, can be applied for immunoassay directly. Here, we show that this proof-of-concept strategy is applicable for both macromolecular and micromolecular antigens by adopting human platelet-derived growth factor-BB (PDGF-BB) and chloramphenicol (CAP) as the model targets, respectively. The detection can be achieved using a colorimetric pH indicator after a 15 min reaction of the immuno-triggered isothermal nucleic acid amplification. In addition, compared with the traditional enzyme-linked immunosorbent assay (ELISA), the performance of our strategy, especially the detection limits, is improved to varying degrees for different targets, making the strategy a promising alternative for diverse application scenarios of immunoassay.

Cucurbit[8]uril-assisted peptide assembly for feasible electrochemical assay of histone acetyltransferase activity.

Accumulating findings demonstrate the importance of histone acetyltransferases (HATs) in regulating the acetylation of histones and reveal that their aberrant catalytic activities are involved in the occurrence and progress of numerous diseases. Herein, a feasible electrochemical method is proposed to assay the activity of HAT. The critical elements of the assay method are the hindrance of HAT-catalyzed acetylation against carboxypeptidase Y-catalyzed digestion and cucurbit[8]uril-assisted peptide assembly, which may recruit peptide-templated silver nanoparticles onto the electrode surface, producing significant electrochemical signals. Taking p300 as a model HAT, the assay method is validated to exhibit desirable selectivity, reproducibility, and usability in inhibitor analysis, and allow absolute activity determination in a linear range from 0.1 to 50 nM with a detection limit of 0.055 nM, which is lower than those of previous reports. Therefore, this work may provide an effective tool for HAT activity assay, which will be of great potential in HAT-related fundamental research, disease diagnosis, and drug development in the future. Graphical abstract ᅟ.

A Dual-Enzyme-Assisted Three-Dimensional DNA Walking Machine Using T4 Polynucleotide Kinase as Activators and Application in Polynucleotide Kinase Assays.

T4 polynucleotide kinase (T4 PNK), an intracellular kinase, catalyzes the phosphorylation of 5'-hydroxyl termini in nucleic acids and plays a crucial role in DNA-related physiological activities. Malfunctioning of PNK is associated with the deregulation of many cellular activities and eventually induces a variety of human diseases. Herein, we report a smart three-dimensional (3D) DNA walking machine using PNK as an effective activator when coupled with the duplex DNA nuclease-assisted cleavage reaction. The 3D DNA tracks benefit from high DNA loading capacity of gold nanoparticles, and the high efficiency of duplex nuclease-mediated cyclic cleavage facilitates the movement of the DNA machine in response to T4 PNK. The DNA machine is also applied for the PNK assay based on the signal amplification from point to area during the DNA walking process. The method achieves an excellent detection limit of 0.0067 U/mL with a linear range from 0.01 to 0.3 U/mL and a favorable specificity even in complex serum samples. Therefore, the 3D DNA machine shows great potential in biochemical and molecular biology studies, drug discovery, and clinic diagnostics.

Chemical Peeling with a Modified Phenol Formula for the Treatment of Facial Freckles on Asian Skin.

BACKGROUND: Chemical peeling is an efficient method for the treatment of pigment disorders. For freckles, medium-depth to deep peeling using a phenol solution is one of the most effective chemical peels, and modifications of facial skin can be observed up to 20 years after peeling. However, applying phenol to the skin may cause serious side effects. Phenol peeling has been rarely used in Asia due to its tendency to cause permanent pigmentary changes and hypertrophic scars. METHODS: In total, 896 Chinese inpatients with facial freckles were enrolled in this study. The phenol formula was modified with crystalline phenol, dyclonine, camphor, anhydrous alcohol and glycerin and adjusted to a concentration of 73.6-90.0%. The entire peeling treatment was divided into two procedures performed separately on 2 days. RESULTS: All patients exhibited 26% or greater improvement, and 99.66% of patients exhibited 51% or greater improvement (good and excellent). Scarring and systemic complications were not observed in any patient. CONCLUSIONS: The modified phenol formula is very effective and safe for the treatment of facial freckles in Asian patients. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Negative Enthalpy Variation Drives Rapid Recovery in Thermoplastic Elastomer.

The mechanism behind the resilience of polymeric materials, typically attributed to the well-established entropy elasticity, often ignores the contribution of enthalpy variation (ΔH), because it is based on the assumption of an ideal chain. However, this model does not fully account for the reduced resilience of thermoplastic polyurethane (TPU) during long-range deformation, which is mainly caused by the dynamics of physical crosslink networks. Such reduction is undesirable for long-range stretchable TPU considering its wide application range. Therefore, a negative ΔH effect is established in this work to facilitate instant recovery in long-range stretchable TPU, achieved by constructing a reversible interim interface via strain-induced phase separation. Consequently, the newly constructed dual soft segmental TPU shows resilience efficiency exceeding 95%, surpassing many synthetic high-performance TPUs with typical efficiencies below 80%, and comparable to biomaterials. Moreover, a remarkable hysteresis loop with a ratio exceeding 50%, makes it a viable candidate for applications such as artificial ligaments or buffer belts. The research also clarifies structural factors influencing resilience, including the symmetry of the dual soft segments and the content of hard segments, offering valuable insights for the design of highly resilient long-range stretchable elastomers.

Non-Woven Fabric Thermal-Conductive Triboelectric Nanogenerator via Compositing Zirconium Boride.

With the vigorous development of the Internet of Things, 5G technology, and artificial intelligence, flexible wearable sensors have received great attention. As a simple and low-cost power supply in wearable sensors, the triboelectric nanogenerator (TENG) has a wide range of applications in the field of flexible electronics. However, most polymers are thermally poor conductors (less than 0.1 W/(m·K)), resulting in insufficient heat dissipation performance and limiting the development of TENG. In this study, a high-performance non-woven fabric TENG with strong thermal conductivity (0.26 W/m·K) was achieved by introducing ZrB2 into the polyurethane (PU) matrix. The excellent output performance with an open circuit voltage (Voc) of 347.6 V, a short circuit current (Isc) of 3.61 µA, and an accumulated charge of 142.4 nC endows it with good sensitivity. The electrospun PU/ZrB2 composites exhibit excellent sensing performance to detect body movements in situ, such as pressing, clapping, running, and walking. Moreover, the generated power can light up 224 LED bulbs as a demonstration of self-powering ability.

Maximizing Interlaminar Fracture Toughness in Bidirectional GFRP through Controlled CNT Heterogeneous Toughening.

"Interleaving" is widely used for interlaminar toughening of fiber-reinforced composites, and the structure of interleaving is one of the important factors affecting the toughening efficiency of laminates. Several experiments have demonstrated that compared to continuous and dense structures, toughening layers with structural heterogeneity can trigger multiple toughening mechanisms and have better toughening effects. On this basis, this work further investigates the application of heterogeneous toughening phases in interlaminar toughening of bidirectional GFRP. CNT was selected to construct toughening phases, which was introduced into the interlaminar of composites through efficient spraying methods. By controlling the amount of CNT, various structures of CNT toughening layers were obtained. The fracture toughness of modified laminates was tested, and their toughening mechanism was analyzed based on fracture surface observation. The results indicate that the optimal CNT usage (0.5 gsm) can increase the initial and extended values of interlayer fracture toughness by 136.0% and 82.0%, respectively. The solvent acetone sprayed with CNT can dissolve and re-precipitate a portion of the sizing agent on the surface of the fibers, which improves the bonding of the fibers to the resin. More importantly, larger discrete particles are formed between the layers, guiding the cracks to deflect in the orientation of the toughened layer. This generates additional energy dissipation and ultimately presents an optimal toughening effect.

Solitary eosinophilic granulocytic sarcoma in a dog.

A 6-year-old male golden retriever presented with swelling of the left upper eyelid of 2 months duration, which did not improve following a course of antibiotics. Routine serum biochemistry, complete blood count and diagnostic imaging identified no clinically significant abnormalities. The mass was surgically excised, and histopathologic examination was performed. Eosinophilic granulocytic sarcoma (GS) was diagnosed based on the results of histopathology and immunohistochemistry. This is the first report of GS affecting the eyelid of a dog.

Metal-organic framework integrated hydrogel bioreactor for smart detection of metal ions.

Bioreactors with environment responsiveness for smart detection has attracted widespread interest. Bioreactors that operate in liquid have excellent reaction speed and sensitivity, and those that operate at a solid interface have unique portability and stability. However, bioreactors that can simultaneously take advantage of both properties are still limited. Here, we developed a metal-organic framework (MOF) integrated hydrogel bioreactor that can accommodate both solid and liquid properties by using a hydrogel as a quasi-liquid medium. To enhance the stability and intelligence of the hydrogel bioreactor, we have opted for the utilization of europium metal-organic framework (Eu-MOF) as the optical output to withstand long-term storage challenges, and DNA as the highly programmable substance for intelligent target response. On this basis, smart detection of metal ions and biological micro-molecules have been achieved. Notably, this quasi-liquid hydrogel bioreactor has effectively tackled the intrinsic issues of inadequate dispersion stability of Eu-MOF in liquid systems and poor stability of DNA against environmental interference. Moreover, this MOF integrated hydrogel bioreactor has been applied to the construction of a portable hydrogel bioreactor, which enables platform-free and arrayed target detection via a smartphone, providing a new perspective for further promoting the application of quasi-liquid hydrogel bioreactors and intelligent nanobiological sensors.

Free-Standing CNT Film for Interlaminar Toughening: Insight into Infiltration and Thickness Effects.

Carbon fiber reinforced polymer composites have the advantages of being lightweight, having high strength and designability, and having been extensively used. However, the interlaminar toughness and delamination resistance of these composites are relatively poor due to their laminated structure and intrinsic brittleness of resin matrix. In this paper, commercialized free-standing carbon nanotube (CNT) films, drawn from CNT forests, were used to toughen the interlaminar interfaces of the composites. The effects of resin infiltration state and thickness of CNT films on the interlaminar toughening effect were systematically investigated. The results show that the pre-infiltration treatment of CNT films with acetone diluted epoxy resin solution can effectively improve the degree of resin infiltration. Compared with the samples containing untreated CNT film, the Mode I and Mode II interlaminar fracture toughness of the treated samples were significantly improved. The GIC reached a maximum of 1412.42 J/m2 at a CNT film thickness of 5 µm, which was about 61.38% higher than that of the baseline. At a CNT film thickness of 15 µm, the GIIC reached a maximum value of 983.73 J/m2, approximately 67.58% higher than that of the baseline. The corresponding toughening mechanisms were also systematically analyzed.

Bile duct hamartoma in a dog.

An 11-year-old female Collie presented with a significantly increased abdominal circumference. Computed tomography of the abdomen revealed that the left lateral lobe of the liver contained a large mass, which was excised via laparotomy. Histologically, many small, dilated, cystic luminal structures were anastomosed and connected to a net-like structure. Immunohistochemistry revealed cytokeratin 19-immunopositive areas, representing bile duct structures in the cystic lumen. Based on these results, the tumour was diagnosed as a bile duct hamartoma. To our knowledge, this is the first report of a bile duct hamartoma in a dog.