Krabbetuttle6664
Implant-associated infections and inadequate osseointegration are two challenges of implant materials in orthopedics. In this study, a lithium-ion-loaded (Li+)/mussel-inspired antimicrobial peptide (AMP) designed to improve the osseointegration and inhibit bacterial infections effectively is prepared on a polyetheretherketone (PEEK) biomaterial surface through the combination of hydrothermal treatment and mussel-inspired chemistry. The results illustrate that the multifunctional PEEK material demonstrated a great inhibitory effect on Escherichia coli and Staphylococcus aureus, which was attributed to irreversible bacterial membrane damage. In addition, the multifunctional PEEK can simultaneously upregulate the expression of osteogenesis-associated genes/proteins via the Wnt/β-catenin signaling pathway. Furthermore, an in vivo assay of an infection model revealed that the multifunctional PEEK implants killed bacteria with an efficiency of 95.03%. More importantly, the multifunctional PEEK implants accelerated the implant-bone interface osseointegration compared with pure PEEK implants in the noninfection model. Overall, this work provides a promising strategy for improving orthopedic implant materials with ideal osseointegration and infection prevention simultaneously, which may have broad application clinical prospects.The course of melanin formation is yet not thoroughly resolved on a mechanistic level. With the present study, incubations of catechin (CA)- and cysteine-derived dihydro-1,4-benzothiazine carboxylic acid derivatives were investigated for colored products during enzymatic browning. Analyses by high-performance liquid chromatography (HPLC)-mass spectrometry revealed the formation of two novel decarboxylated dihydro-1,4-benzothiazine derivatives [8-(3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl)-5-hydroxy-3,4-dihydro-2H-benzothiazine and 7-(3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl)-5-hydroxy-3,4-dihydro-2H-benzothiazine] preferentially under acidic conditions. Furthermore, in model reactions under neutral pH, a colored phenazine dimer intermediate was isolated by high-performance countercurrent chromatography and preparative HPLC when conducting the incubations in the presence of o-phenylenediamine (OPD). Mass spectrometry and nuclear magnetic resonance spectroscopy unequivocally verified the structure as (12E)-5,5'-dioxo-11a,11a'-bis(3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl)-3,3',4,4',5a,5a',6,6',11,11',11a,11a'-dodecahydro-2H,2'H,5H,5'H-12,12'-bi[1,4]thiazino[2,3-b]phenazine-3,3'-dicarboxylic acid. Enzymatically catalyzed incubations under aeration starting from the initial CA-cysteine adducts and their follow-up dihydro-1,4-benzothiazine carboxylic acids, respectively, proved that the unstable colored compound was a trichochrome-like reaction intermediate of the browning reaction cascade which can be trapped by postincubation with OPD, thus verifying their direct mechanistic relationship.Modern electrochemical and electronic devices require advanced electrolytes. Liquid crystals have emerged as promising electrolyte candidates due to their good fluidity and long-range order. However, the mesophase of liquid crystals is variable upon heating, which limits their applications as high-temperature electrolytes, e.g., implementing anhydrous proton conduction above 100 °C. Here, we report a highly stable thermotropic liquid-crystalline electrolyte based on the electrostatic self-assembly of polyoxometalate (POM) clusters and zwitterionic polymer ligands. These electrolytes can form a well-ordered mesophase with sub-10 nm POM-based columnar domains, attributed to the dynamic rearrangement of polymer ligands on POM surfaces. Notably, POMs can serve as both electrostatic cross-linkers and high proton conductors, which enable the columnar domains to be high-temperature-stable channels for anhydrous proton conduction. These nanochannels can maintain constant columnar structures in a wide temperature range from 90 to 160 °C. This work demonstrates the unique role of POMs in developing high-performance liquid-crystalline electrolytes, which can provide a new route to design advanced ion transport systems for energy and electronic applications.The structural diversity of natural products offers unique opportunities for drug discovery, but challenges associated with their isolation and screening can hinder the identification of drug-like molecules from complex natural product extracts. Here we introduce a mass spectrometry-based approach that integrates untargeted metabolomics with multistage, high-resolution native mass spectrometry to rapidly identify natural products that bind to therapeutically relevant protein targets. By directly screening crude natural product extracts containing thousands of drug-like small molecules using a single, rapid measurement, we could identify novel natural product ligands of human drug targets without fractionation. This method should significantly increase the efficiency of target-based natural product drug discovery workflows.Apoptosis, as a very important mode of programmed death, is closely associated with many diseases. Real-time in situ monitoring of the dynamic change of the apoptotic process remains a great challenge. Herein, a nanoprobe based on the gold-selenium (Au-Se) bond was developed for a sequential fluorescence activation imaging of cytochrome c (Cyt c) and caspase-9, two important apoptotic signaling molecules, to monitor the progression of apoptosis. The Cyt c aptamer and caspase-9-cleavable peptide chains labeled with two dyes were modified onto the surface of gold nanoparticles (Au NPs) by the Au-Se bond, which can be activated by upstream Cyt c and downstream caspase-9 to trigger fluorescence recovery. The Au-Se nanoprobe exhibited good specificity and stability. Compared with the traditional nanoprobe based on the gold-sulfur (Au-S) bond, the interference of biological thiols on the Au-Se nanoprobe can be effectively avoided. Importantly, the Au-Se nanoprobe can image the sequential changes of the two markers in situ in real time during cell apoptosis. This work provides an effective tool for the accurate and real-time detection of apoptosis and is conducive to the in-depth study of the relationship between apoptosis and disease.Artificial compound eyes (ACEs) endowed with durable superhydrophobicity, wide field-of-view (FOV), and antireflection properties are extremely appealing in advanced micro-optical systems. However, the simple and high-efficiency fabrication of ACEs with these functions is still a major challenge. Herein, inspired by moth eyes, ACEs with hierarchical macro/micro/nano structures were fabricated using the combination of nanotip-focused electrohydrodynamic jet (NFEJ) printing and air-assisted deformation processes. NSC 649890 The NFEJ printing enables the direct and maskless fabrication of hierarchical micro/nanolens arrays (M/NLAs) without intermediate steps. The introduction of M/NLAs on the eye surface significantly improves the water hydrophobic performance with a water contact angle of 161.1° and contact angle hysteresis (CAH) of 4.2° and generally decreases the reflectance by 51% in the wavelength range of 350-1600 nm in comparison to the macroeye without any structures. The contact angle remains almost unchanged, and the CAH slightly increases from 4.2° to 8.7° after water jet impact for 20 min, indicating a durable superhydrophobicity. Moreover, the results confirm that the durable superhydrophobic ACEs with antireflection properties exhibit excellent imaging quality and a large FOV of up to 160° without distortion.A new Os(II) complex dyad featuring direct singlet-to-triplet (S-T) absorption and intramolecular triplet energy transfer (ITET) with lifetime up to 7.0 μs was designed to enhance triplet energy transfer efficiency during triplet-triplet annihilation upconversion (TTA-UC). By pairing with 9,10-bis(phenylethynyl)anthracene (BPEA) as a triplet acceptor, intense upconverted green emission in deaerated solution was observed with unprecedented TTA-UC emission efficiency up to 26.3% (with a theoretical maximum efficiency of 100%) under photoexcitation in the first biological transparency window (650-900 nm). Meanwhile, a 7.1% TTA-UC emission efficiency was acquired in an air-saturated hydrogel containing the photosensitizer and a newly designed hydrophilic BPEA derivative. This ITET mechanism would inspire further development of a highly efficient TTA-UC system for biological fields and renewable energy production.Conversion of common reactants to diverse products is a key objective of organic syntheses. Recent developments in transition-metal-catalyzed C-H functionalization have increased the interest in such conversions. Both the position of functionalization and the type of the substituent can be varied, allowing systematic diversification of common structural cores. Because five-membered heteroarenes (pyrazole, imidazole, thiazole, pyrrole, and thiophene) are ubiquitous in pharmaceuticals and organic functional materials, the selective C-H functionalization of these heterocyclic cores facilitates both the optimization of their physicochemical properties and streamlining of their preparation. In addition, the parent forms of these heterocycles are more readily available and inexpensive than any other derivatives of their families. Hence, their nondirected C-H functionalization is highly desirable. Although various regioselective reactions have been developed, many of them target the most reactive site; hence, exceptcle intermediates.Other research groups have also contributed to the development of divergent reactions, in investigations ranging from the pioneering studies in the early days of research on C-H functionalization to recent studies with new ligands. We have also discussed these studies in context. These approaches provide access to many heteroarenes with systematically varied substituents. We believe that new ligand systems and mechanistic insights gained through these studies will enrich fields beyond C-H functionalization of five-membered heteroarenes.The gut microbiome is essential to maintain overall health and prevent disease, which can occur when these microbes are not in homeostasis. Microbial biotherapeutics are important to combat these issues, but they must be alive at the time of delivery for efficacy. Many potentially therapeutic species are anaerobes and thus are difficult to manufacture because of the limited efficacy of existing protective methods, making their production nearly impossible. We have developed a self-assembling cellular coating to improve the viability and stability of the next-generation biotherapeutic Bacteroides thetaiotaomicron. We show protection from both harsh processing conditions and oxygen exposure, even in the absence of canonical cryoprotectants. This advance will increase the range of microbes that can be stably manufactured and facilitate the development of emerging strains of interest by ensuring their postproduction viability.Inappropriate cancer management can be prevented by simultaneous cancer diagnosis, treatment, and real-time assessment of therapeutic processes. Here, we describe the design of a two-photon (TP) photosensitizer (PS), ACC-B, for high temporal and spatioselective near-infrared cancer therapy. ACC-B consisting of a biotin unit significantly enhanced the cancer sensitivity of the PS. Upon TP irradiation, ACC-B generated reactive oxygen species (ROS) through the type I photodynamic therapy (PDT) process and triggered highly selective cancer ablation. In addition, fluorescence microscopy images revealed that ACC-B-loaded live human colon tissues showed a marked difference in ACC-B uptake between normal and cancer tissues, and this property was used for real-time imaging. Upon 770 nm TP treatment, ACC-B generated ROS efficiently in live colon cancer tissues with high spatial selectivity. During PDT, ACC-B can provide in situ spatioselective visualization of cellular behavior and molecular information for therapeutic assessment in specific regions.