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81.
In this review,the most recent progresses in the field of fluorescence signal amplification strategies based on DNA nanotechnology for miRNA are summarized.The types of signal amplification are given and the principles of amplification strategies are explained,including rolling circle amplification(RCA),catalytic hairpin assembly(CHA),hybridization chain reaction(HCR)and DNA walker.Subsequently,the application of these signal amplification methods in biosensing and bioimaging are covered and described.Finally,the challenges and the outlook of fluorescence signal amplification methods for miRNA detection are briefly commented. 相似文献
82.
The concept of aggregation‐induced emission (AIE) has opened new opportunities in many research fields. Motivated by the unique feature of AIE fluorogens (AIEgens), during the past decade, many AIE molecular probes and AIE nanoparticle (NP) probes have been developed for sensing, imaging and theranostic applications with excellent performance outperforming conventional fluorescent probes. This Review summarizes the latest advancement of AIE molecular probes and AIE NP probes and their emerging biomedical applications. Special focus is to reveal how the AIE probes are evolved with the development of new multifunctional AIEgens, and how new strategies have been developed to overcome the limitations of traditional AIE probes for more translational applications via fluorescence imaging, photoacoustic imaging and image‐guided photodynamic/photothermal therapy. The outlook discusses the challenges and future opportunities for AIEgens to advance the biomedical field. 相似文献
83.
Haixiao Fang Hang Zhang Lin Li Yun Ni Riri Shi Zheng Li Xuekang Yang Bo Ma Chengwu Zhang Qiong Wu Changmin Yu Naidi Yang Shao Q. Yao Wei Huang 《Angewandte Chemie (International ed. in English)》2020,59(19):7536-7541
Monoamine oxidases have two functionally distinct but structurally similar isoforms (MAO‐A and MAO‐B). The ability to differentiate them by using fluorescence detection/imaging technology is of significant biological relevance, but highly challenging with available chemical tools. Herein, we report the first MAO‐A‐specific two‐photon fluorogenic probe ( F1 ), capable of selective imaging of endogenous MAO‐A enzymatic activities from a variety of biological samples, including MAO‐A‐expressing neuronal SY‐SY5Y cells, the brain of tumor‐bearing mice and human Glioma tissues by using two‐photon fluorescence microscopy (TPFM) with minimal cytotoxicity. 相似文献
84.
Sen Ye Nir Hananya Ori Green Hansen Chen Angela Qian Zhao Jiangang Shen Doron Shabat Dan Yang 《Angewandte Chemie (International ed. in English)》2020,59(34):14326-14330
Selective and sensitive molecular probes for hydrogen peroxide (H2O2), which plays diverse roles in oxidative stress and redox signaling, are urgently needed to investigate the physiological and pathological effects of H2O2. A lack of reliable tools for in vivo imaging has hampered the development of H2O2 mediated therapeutics. By combining a specific tandem Payne/Dakin reaction with a chemiluminescent scaffold, H2O2‐CL‐510 was developed as a highly selective and sensitive probe for detection of H2O2 both in vitro and in vivo. A rapid 430‐fold enhancement of chemiluminescence was triggered directly by H2O2 without any laser excitation. Arsenic trioxide induced oxidative damage in leukemia was successfully detected. In particular, cerebral ischemia‐reperfusion injury‐induced H2O2 fluxes were visualized in rat brains using H2O2‐CL‐510 , providing a new chemical tool for real‐time monitoring of H2O2 dynamics in living animals. 相似文献
85.
Optical imaging plays a growing role in modern biomedical research and clinical applications due to its high sensitivity, superb spatiotemporal resolution and minimal hazards. Lanthanide‐doped nanoparticles (LDNPs), as a classical category of luminescent materials, exhibit promising photostability, near‐infrared (NIR)‐excited frequency up‐/down‐converting capabilities, emission fine‐tuning and multispectral features, which have greatly promoted the endeavors of deeper and clearer diagnostics in complex living conditions. This review focuses on the recent advances of LDNP‐based multipurpose imaging studies using upconversion, downshifting, lifetime, photoacoustic and multimodal nanoprobes in the NIR (650–1000 nm) and the second near‐infrared window (NIR‐II, 1000–1700 nm). The principle and design of various functional, activatable, multiplexing or multimodal lanthanide‐imaging nanoprobes (LINPs) as well as representative biophotonic applications are summarized in detail. In addition, the future perspectives and challenges for facilitating LINPs to clinical translations are discussed. 相似文献
86.
Additive manufacturing technologies, generally grouped under the name of 3D printing, are experiencing an explosion of interest during the last few years. The possibility of fast prototyping enabled by 3D printing has been recognized as a crucial booster for device fabrication and general scientific advancements. In this review, attention is focused on the latest developments in the field of redox flow batteries which are, similar to other energy related devices, characterized by the recent adoption of 3D printing methods for the fabrication of key components. Whether simply to investigate flow phenomena, test new designs or fabricate final-product components with custom features, the use of 3D printing can critically drive this field of research towards better performing energy-storage systems. The latest and most representative examples of redox flow battery studies will be discussed, categorized in relation to the electrolyte used and whether the devices are employed in aqueous or non-aqueous applications. 相似文献
87.
Tatsuaki Wada 《Physics letters. A》2011,375(20):2037-2040
Gauss? principle in statistical mechanics is generalized for a q-exponential distribution in nonextensive statistical mechanics. It determines the associated stochastic and statistical nonextensive entropies which satisfy Greene-Callen principle concerning on the equivalence between microcanonical and canonical ensembles. 相似文献
88.
Changfeng FangBin Cui Yuqing XuGuomin Ji Desheng Liu Shijie Xie 《Physics letters. A》2011,375(41):3618-3623
We report first-principles calculations of the current-voltage characteristic and the conductance of carbon-based molecular wires with different length capped with sulfur ends between two metallic electrodes made of different metals. The optimized molecular structure of carbon chain in the junction is presented on the structure of polyyne. The conductance of the polyyne wires shows oscillatory behavior depending on the number of carbon atoms (triple bonds). Current rectification is found and rectification direction presents inversion with the odd and even number of carbon atoms. 相似文献
89.
We generalize the usual two-strategy prisoner?s dilemma game to a multi-strategy game, in which the strategy variable s is allowed to take q different fractional values lying between 0 and 1. The fractional-valued strategies signify that individuals are not absolutely cooperative or defective, instead they can adopt intermediate strategies. Simulation results on 1D and 2D lattices show that, compared with the binary strategy game, the multi-strategy game can sustain cooperation in more stringent defective environments. We give a comprehensive analysis of the distributions of the survived strategies and we compare pairwise the relative strength and weakness of different strategies. It turns out that some intermediate strategies survive the pure defection because they can reduce being exploited and at the same time benefit from the spatial reciprocity effect. Our work may shed some light on the intermediate behaviors in human society. 相似文献
90.
Zdzis?aw Meglicki 《Physics letters. A》2011,375(27):2606-2616
We discuss Hardy?s paradox and weak measurements by using multitasking diagrams, which are introduced to illustrate the progress of quantum probabilities through the double interferometer system. We explain how Hardy?s paradox is avoided and elaborate on the outcome of weak measurements in this context. 相似文献