A D-Y Shaped Neuropeptide Y Mimetic Peptide-Dye Self-Assembly with Maximal Emission Beyond 1300 nm and Glioma Mitochondrial Activity Modulation.

Neuropeptide Y (NPY), as one of the most abundant neuropeptides known, is widely distributed in the central and peripheral nervous system. However, most of the reported NPY-mimetic peptides are hard to cross the blood-brain barrier, target glioma mitochondria, and achieve self-assembly nanostructure in situ. Here, based on the α-helix structure of the novel chiral NPY-mimetic peptides D/LNPY(14), a Y-shaped peptide is designed with the sequences that can be recognized by enterokinase and achieved nanofibers conversion in glioma cell mitochondria. Coupling the Y-shaped NPY-mimetic peptide with the NIR-II fluorophore IR1048, a red-shifting of the fluorescence spectrum beyond 1300 nm is achieved through self-assembly. After the self-assembly in glioma mitochondria, the formed nanofibers can promote intracellular mitochondrial ROS production and extend the NIR-II fluorescence imaging time to at least 7 days in vivo. This work for the first time endows the self-assembly of α-helical-based chiral NPY-mimetic peptides, providing a novel strategy for glioma subcellular regulation enhanced antitumor treatment guided by NIR-II fluorescence imaging.

Organic small-molecule fluorescent probe-based detection for alkali and alkaline earth metal ions in biological systems.

Metal ions widely exist in biological systems and participate in many vital biochemical processes. Monitoring and analyzing metal ions in biological systems can help reveal physiological processes and understand disease causes. There are various detection methods for metal ions, among which organic small-molecule fluorescent probes have significant advantages, such as high fluorescence quantum yield, easy modification, good biocompatibility, high sensitivity, and fast real-time detection. This review presents recent studies on fluorescent probes for alkali and alkaline earth metal ions (including Na+, K+, Ca2+, and Mg2+) in biological systems. All the candidates are organized according to their structures, and the sensing mechanisms of fluorescent probes are also highly taken into account. Finally, the challenges, trends and prospects of fluorescent probes in metal ion detection are discussed. We hope that this review can provide guidance for the development of fluorescent molecular probe-based alkali and alkaline earth metal ion detection methods in the future.

Recent progress on near-infrared fluorescence heptamethine cyanine dye-based molecules and nanoparticles for tumor imaging and treatment.

Recenly, near-infrared fluorescence heptamethine cyanine dyes have shown satisfactory values in bioengineering, biology, and pharmacy especially in cancer diagnosis and treatment, owing to their excellent fluorescence property and biocompatibility. In order to achieve broad application prospects, diverse structures, and chemical properties of heptamethine cyanine dyes have been designed to develop novel functional molecules and nanoparticles over the past decade. For fluorescence and photoacoustic tumor imaging properties, heptamethine cyanine dyes are equipped with good photothermal performance and reactive oxygen species production properties under near-infrared light irradiation, thus holding great promise in photodynamic and/or photothermal cancer therapies. This review offers a comprehensive scope of the structures, comparisons, and applications of heptamethine cyanine dyes-based molecules as well as nanoparticles in tumor treatment and imaging in current years. Therefore, this review may drive the development and innovation of heptamethine cyanine dyes, significantly offering opportunities for improving tumor imaging and treatment in a precise noninvasive manner. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Decomposition Analysis of Factors Affecting Changes in Industrial Wastewater Emission Intensity in China: Based on a SSBM-GMI Approach.

This paper investigated the factors driving the changes in industrial wastewater emission intensity (IWEI) across provinces in China. To do this, we proposed a Super-efficiency Slacks-based Measure-Global Malmquist Index (SSBM-GMI) to decompose the change in IWEI into the effects from efficiency change (ECE), technological change (TCE), capital⁻wastewater substitution (KWE) and labor⁻wastewater substitution (LWE). The method was applied to conduct an empirical study using Chinese provincial data from 2003⁻2015. The main findings include the following: firstly, TCE was the dominant driving force behind the reduction in IWEI with an average annual contribution of -6.4% at the national level, followed by KWE (-5.3%), LWE (-1.8%) and ECE (1.2%). Secondly, significant differences exist in the driving factors behind the reduction in IWEI across regions. The reduction in IWEIs in the Northeast area and the Great Northwest area was mainly driven by productivity growth, while the reduction in IWEIs in the other areas was mainly driven by factor substitution. Thirdly, the shortage of KWE and LWE has impeded IWEI reduction in the Great Northwest area, the Middle Reaches of the Yellow River, the Northeast area and the North area. Finally, some particular policy implications were also recommended for reducing industrial wastewater emission in China.

A chitosan/gelatin/aldehyde hyaluronic acid hydrogel coating releasing calcium ions and vancomycin in pH response to prevent the formation of bacterial biofilm.

Osteomyelitis is a refractory disease of orthopedics, part of which is caused by medical implants. The main difficulties in treatment are the barrier effect after the formation of bacterial biofilm, and the difficulty in achieving sustained antibiotic intervention. In view of this situation, we studied a hydrogel coating that can release CaCl2 and vancomycin in pH-responsive manner. We used nano-TiO2 to modify Chitosan/ Gelatin/Aldehyde Hyaluronic Acid (CS/Gel/AHA) hydrogel, and combined with the dip-coating technique, prepared a coating with good mechanical strength. The hydrogel-loaded zeolitic imidazolate framework (ZIF) decomposes under acidic conditions, and the released Ca2+ act on the bacterial Bap protein to inhibit the formation of biofilm, and the released vancomycin kills free bacteria. The antibacterial coating achieved good bactericidal effect in both in vitro experiments and rat subcutaneous implant model. These results not only provide a new way to enhance the strength of hydrogels to prepare coatings, but also utilize a new approach to responsively inhibit the formation of biofilms, showing the promising application prospects of the coating in antibacterial treatment of medical implants.