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Cancer is a global disease which has been disturbing researchers in medicine and seriously threatens patients' health and lifetime around the world in the past several decades. Due to the characteristics of cancer cells, such as uncontrollable cell proliferation, cell invasion and metastasis to surrounding tissues, lower grade of differentiation, higher telomerase activity and others, it has been one of the most usual lethal factors, next to heart disease in incidence. Cancer mortality can be decreased by early diagnosis, and the people who with treatment at an early stage have an obvious improved survival rate. Consequently, early detection is significant for better understanding the pathogenesis of cancer and improving the prognosis of patients. In situ detection technique is a vital tool for imaging and cellular pathology research, which can provide effective information about tumor markers in the early cancer detection. In view of low expression of most tumor markers in the early stage of cancers, detection techniques based on DNA signal amplification and DNA nanodevices can provide a strong support for the diagnosis and detection of cancers. In this review, we summarize the research progress of different analytical techniques for detecting various tumor markers that have been reported in recent years. We compare different DNA amplification and nanodevices, then provide guidance and suggestions for better understanding in situ analysis of cancer cells. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a common type of malignant tumor with high incidence and mortality, and is the third leading cause of cancer‐related death in human. High‐precision detection of tumor markers, such as microRNA (miRNA), is expected to contribute to the early diagnosis of HCC as well as improve the survival rate of HCC patients. In recent years, great effort has been made to develop different methods to detect HCC‐associated miRNA, in which signal amplification strategies are incorporated to realize high sensitivity. Among them, isothermal nucleic acid signal amplification is an emerging signal amplification technology which has the advantages of high amplification efficiency, good reproducibility, and easy operation for real‐time analysis. Herein, we provide an overview of the advances in the application of isothermal nucleic acid signal amplification in HCC‐associated miRNA detection by highlighting several representative works in recent years. MicroRNA is a low‐abundance biomarker closely linked to the occurrence and development of hepatocellular carcinoma. Isothermal nucleic acid signal amplification is an efficient and sensitive microRNA detection method that is easy to conduct without extensive instrumentation. The application of this method for the detection of microRNA associated with hepatocellular carcinoma is reviewed. [ABSTRACT FROM AUTHOR]

Details are given of a study of the characteristics of field-induced electron emission from hydrogen-free high sp3 content (>90%) amorphous diamond (a-D) film deposited on heavily doped (ρ<0.01ω·cm) n-type monocrystalline Si (111) substrate. It is demonstrated that a-D film has excellent electron field emission properties. The emission current can reach 0.9 μA at applied field as low as 1 V/μm, and the emission current density can be about several mA/cm2 under 20 V/μm. The emission current is stable when the beginning current is at 50 μA within 72 h. Uniform fluorescence display of electron emission from the whole face of the a-D film under the electric field of 10–12 V/μm is also observed. The contribution of excellent electron emission property results from the smooth, uniform, amorphous surface and high sp3 content of the a-D film. [ABSTRACT FROM AUTHOR]

Expansion microscopy (ExM) facilitates nanoscale imaging under conventional microscopes, but it frequently encounters challenges such as fluorescence losses, low signal-to-noise ratio (SNR), and limited detection throughput. To address these issues, a method of orthogonal DNA self-assembly-based ExM (o-DAExM) platform is developed, which employs hybridization chain reaction instead of conventional fluorescence labeling units, showcasing signal amplification efficacy, enhancement of SNR, and expandable multiplexing capability at any stage of the ExM process. In this work, o-DAExM has been applied to compare with immunofluorescence-based ExM for cellular cytoskeleton imaging, and the resolved nanoscale spatial distributions of cytoskeleton show outstanding performance and reliability of o-DAExM. Furthermore, the study demonstrates the utility of o-DAExM in accurately revealing exosome heterogeneous information and multiplexed analysis of protein targets in single cells, which provides infinite possibilities in super-resolution imaging of cells and other samples. Therefore, o-DAExM offers a straightforward expansion and signal labeling method, highlighting future prospects to study nanoscale structures and functional networks in biological systems., (© 2024 Wiley‐VCH GmbH.)

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., (© 2024 Wiley‐VCH GmbH.)

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., (© 2023 Wiley-VCH GmbH.)

DNA nanomachines developed by DNA nanotechnology, an attractive branch of nanoengineering, have been widely applied in drug delivery, biomarker detection, etc. However, the existing DNA nanomachines are mainly conducted in solution systems and the application of surface-confined DNA nanomachines is limited due to the less variety and lower efficiency than those in a solution. The efficiency is greatly limited due to the fact that the surface-confined substances cannot freely perform the Brownian movement, which is not conducive to performance improvement. In this work, we proposed a DNA nanomachine with multitentacles based on the multivalent effect and confirmed that the processing efficiency of multitentacles is much higher than that of a single tentacle by kinetic experiments. Interestingly, a multitentacle DNA nanomachine enables stable capture and integral processing of nanoparticles through only one collision between the surface and the nanoparticle, avoiding the loss of efficiency caused by repeated collisions. In addition, a multitentacle DNA nanomachine-based immunoassay exhibits comparable sensitivity to traditional enzyme-linked immunosorbent assay (ELISA) methods in practical applications. Therefore, it is believed that the construction and application of a multitentacle DNA nanomachine expand the application of DNA nanomachines in interfacial biosensing systems, e.g., ELISA and electrochemical biosensors, and provide ideas for the design of other nanomachines working on the interface.