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The epigenetic modification of nucleic acids represents a versatile approach for achieving high-efficient control over gene expression and transcription and could dramatically expand their biosensing and therapeutic applications. Demethylase-involved removal of N6-methyladenine (m6A) represents one of the vital epigenetic reprogramming events, yet its direct intracellular evaluation and as-guided gene regulation are extremely rare. The endonuclease-mimicking deoxyribozyme (DNAzyme) is a catalytically active DNA that enables the site-specific cleavage of the RNA substrate, and several strategies have imparted the magnificent responsiveness to DNAzyme by using chemical and light stimuli. However, the epigenetic regulation of DNAzyme has remained largely unexplored, leaving a significant gap in responsive DNA nanotechnology. Herein, we reported an epigenetically responsive DNAzyme system through the in vitro selection of an exquisite m6A-caged DNAzyme that could be specifically activated by FTO (fat mass and obesity-associated protein) demethylation for precise intracellular imaging-directed gene regulation. Based on a systematic investigation, the active DNAzyme configuration was potently disrupted by the site-specific incorporation of m6A modification and subsequently restored into the intact DNAzyme structure via the tunable FTO-specific removal of m6A-caging groups under a variety of conditions. This orthogonal demethylase-activated DNAzyme amplifier enables the robust and accurate monitoring of FTO and its inhibitors in live cells. Moreover, the simple demethylase-activated DNAzyme facilitates the assembly of an intelligent self-adaptive gene regulation platform for knocking down demethylase with the ultimate apoptosis of tumor cells. As a straightforward and scarless m6A removal strategy, the demethylase-activated DNAzyme system offers a versatile toolbox for programmable gene regulation in synthetic biology.The magneto-optical phenomenon known as Faraday rotation involves the rotation of plane-polarized light as it passes through an optical medium in the presence of an external magnetic field oriented parallel to the direction of light propagation. Faraday rotators find applications in optical isolators and magnetic-field imaging technologies. In recent years, organic thin films comprised of polymeric and small-molecule chromophores have demonstrated Verdet constants, which measure the magnitude of rotation at a given magnetic field strength and material thickness, that exceed those found in conventional inorganic crystals. We report herein the thin-film magnetic circular birefringence (MCB) spectra and maximum Verdet constants of several commercially available and newly synthesized phthalocyanine and porphyrin derivatives. Five of these species achieved maximum Verdet constant magnitudes greater than 105 deg T-1 m-1 at wavelengths between 530 and 800 nm. Notably, a newly reported zinc(II) phthalocyanine derivative (ZnPc-OT) reached a Verdet constant of -33 × 104 deg T-1 m-1 at 800 nm, which is among the largest reported for an organic material, especially for an optical-quality thin film. The MCB spectra are consistent with resonance-enhanced Faraday rotation in the region of the Q-band electronic transition common to porphyrin and phthalocyanine derivatives, and the Faraday A-term describes the electronic origin of the magneto-optical activity. Overall, we demonstrate that phthalocyanines and porphyrins are a class of rationally designed magneto-optical materials suitable for applications demanding large Verdet constants and high optical quality.Binary blends of water-insoluble polymers are a versatile strategy to obtain nanostructured films at the air-water interface. However, there are few reported structural studies of such systems in the literature. Depending on the compatibility of the polymers and the role of the air-water interface, one can expect various morphologies. In that context, we probed Langmuir monolayers of cellulose acetate (CA), of deuterated and postoxidized polybutadiene (PBd) and three mixtures of CA/PBd at various concentrations by coupling surface pressure-area isotherms, Brewster angle microscopy (BAM), and neutron reflectometry at the air-water interface to determine their thermodynamic and structural properties. The homogeneity of the films in the vertical direction, averaged laterally over the spatial coherence length of the neutron beam (∼5 μm), was assessed by neutron reflectometry measurements using D2O/H2O subphases contrast-matched to the mixed films. At 5 mN/m, the whole mixed films can be described by a single slightly hydrated thin layer. [https://www.selleckchem.com/products/ro5126766-ch5126766.html RO5126766 Raf inhibitor] However, at 15 mN/m, the fit of the reflectivity curves requires a two-layer model consisting of a CA/PBd blend layer in contact with the water, interdiffused with a PBd layer at the interface with air. At intermediate surface pressure (10 mN/m), the determined structure was between those obtained at 5 and 15 mN/m depending on film composition. This PBd enrichment at the air-film interface at high surface pressure, which leads to the PBd depletion in the blend monolayer at the water surface, is attributed to the hydrophobic character of this polymer compared with the predominantly hydrophilic CA.PbCrO3 features an unusual charge distribution Pb0.52+Pb0.54+Cr3+O3 with Pb charge disproportionation at ambient pressure. A charge transfer between Pb and Cr is induced by the application of pressure resulting in Pb2+Cr4+O3 charge distribution and a large volume collapse. Here, structural and charge distribution changes in PbCr1-xVxO3 are investigated. Despite a cubic crystal structure in 0 ≤ x ≤ 0.60, discontinuous reduction in the unit cell volume was observed between x = 0.35 and 0.40. Hard X-ray photoemission spectroscopy confirmed the change in Pb charge state from the coexisting Pb2+ and Pb4+ at x = 0.35 to single Pb2+ at x = 0.40. This indicates that V substitution stabilizes the high pressure cubic Pb2+Cr4+O3-type phase. With further increase in the V substitution, the PbVO3-type polar tetragonal phase appeared at x = 0.80.Biocompatible self-healing hydrogels present an effective application as drug-releasing vehicles for tissue engineering and wound repairing. At the same time, the effective hemostatic property of the hydrogels also improves the application property as wound dressing materials. In this research, the PNIPAM-bearing acylhydrazide P(NIPAM-co-AH) was synthesized and then hemostatic polyphosphate (PolyP) was imported to prepare polyphosphate-conjugated P(NIPAM-co-AH) (PNAP). Through the acylhydrazone connection of PNAP and aldehyde functional PEO (PEO DA), the self-healing hydrogel with a hemostatic property was fabricated with good flexibility and sealing effect. The resultant hydrogels kept excellent biocompatibility and showed controlled drug release behavior. More importantly, the hydrogel accelerated the coagulation rate in vitro and presented a strong hemostatic effect as the binder in the hemorrhage model in vivo, which endow the hemostatic hydrogel with a very useful drug delivery carrier for wound healing applications or first aid treatment of the wounded in critical situations.