RNA-Polymer Hybrids via Direct and Site-Selective Acylation with the ATRP Initiator and Photoinduced Polymerization.

Combining synthetic polymers with RNA paves the way for creating RNA-based materials with non-canonical functions. We have developed an acylation reagent that allows for direct incorporation of the atom transfer radical polymerization (ATRP) initiator into both short synthetic oligoribonucleotides and natural biomass RNA extracted from torula yeast. The acylation was performed in a quantitative yield. The resulting initiator-functionalized RNAs were used for grafting polymer chains from the RNA by photoinduced ATRP, resulting in RNA-polymer hybrids with narrow molecular weight distributions. The RNA initiator was used for the polymerization of oligo(ethylene oxide) methyl ether methacrylate, poly(ethylene glycol) dimethacrylate, and N-isopropylacrylamide monomers, resulting in RNA bottlebrushes, hydrogels, and stimuli-responsive materials. This approach, readily applicable to both post-synthetic and nature-derived RNA, can be used to engineer the properties of a variety of RNA-based macromolecular hybrids and assemblies providing access to a wide variety of RNA-polymer hybrids.

Visible Light-ATRP Driven by Tris(2-Pyridylmethyl)Amine (TPMA) Impurities in the Open Air.

Atom transfer radical polymerization (ATRP) of oligo(ethylene oxide) monomethyl ether methacrylate (OEOMA500 ) in water is enabled using CuBr2 with tris(2-pyridylmethyl)amine (TPMA) as a ligand under blue or green-light irradiation without requiring any additional reagent, such as a photo-reductant, or the need for prior deoxygenation. Polymers with low dispersity (D = 1.18-1.25) are synthesized at high conversion (>95%) using TPMA from three different suppliers, while no polymerization occurred with TPMA is synthesized and purified in the laboratory. Based on spectroscopic studies, it is proposed that TPMA impurities (i.e., imine and nitrone dipyridine), which absorb blue and green light, can act as photosensitive co-catalyst(s) in a light region where neither pure TPMA nor [(TPMA)CuBr]+ absorbs light.

Direct Polymerization Approach to Synthesize Acid-Degradable Block Copolymers Bearing Imine Pendants for Tunable pH-Sensitivity and Enhanced Release.

The development of effective approaches to synthesize smart amphiphilic block copolymers (ABPs) exhibiting acid-responsive degradation through the cleavage of acid-labile imine bonds is extensively explored for controlled release of encapsulated biomolecules, particularly in drug delivery. Here, a new approach based on direct polymerization utilizing a controlled radical polymerization technique to synthesize acid-degradable ABPs bearing pendant imine linkages in hydrophobic block is reported. The approach centers on the synthesis of a novel methacrylate bearing benzoic imine group that can be polymerized to form the hydrophobic imine pendant block. The formed ABPs respond to mild acidic pHs equivalent to tumoral and endosomal/lysosomal acidic environments. This causes the dissociation of self-assembled nanoassemblies through change in their hydrophilic/hydrophobic balance upon the cleavage of pendant imine linkages to the corresponding aldehyde and primary amine, thus leading to the enhanced release of encapsulated drugs. The proof-of-concept results suggest that this robust approach is versatile to further design advanced nanoassemblies responding to dual/multiple stimuli, thus being more effective to intracellular drug delivery.

Comparison of modification of a bacterial uricase with N-hydroxysuccinimide esters of succinate and carbonate of monomethoxyl poly(ethylene glycol).

Uricase after modification with monomethoxy poly(ethylene glycol) (mPEG) is currently the sole agent to treat refractory gout. For formulating Bacillus fastidious uricase, succinimidyl carbonate of mPEG-5000 (SC-mPEG5k) and succinimidyl succinate of mPEG-5000 (SS-mPEG5k) were compared. SC-mPEG5k possessed higher purity, comparable reaction rate constant with glycine but lower hydrolysis rate, and stronger effectiveness to modify amino groups. The uricase possessed two types of amino groups bearing a 25-fold difference in reactivity with SC-mPEG5k or SS-mPEG5k at pH 9.2. Oxonate and xanthine concentration-dependently protected the bacterial uricase from inactivation during PEGylation. With SC-mPEG5k at a molar ratio of 200 to uricase subunits and oxonate of 50 µM, the PEGylated uricase (1) retained about 73% of the original activity, (2) displayed about 10% reactivity to rabbit anti-sera recognizing the native uricase, (3) elicited IgG in rats accounting for about 5% of that by the native uricase, (4) exhibited circulation half-life time of about 25 H in cock plasma in vivo, and (5) concurrently maintained uric acid at lowered levels for over 20 H. Hence, PEGylation with SC-mPEG under the protection of a competitive inhibitor was a practical approach to formulation of the bacterial uricase; protection of enzymes by competitive inhibitors during PEGylation may have universal significance.

Biomass-derived cellulose nanocrystals modified nZVI for enhanced tetrabromobisphenol A (TBBPA) removal.

Nano zero-valent iron (nZVI) is an advanced environmental functional material for the degradation of tetrabromobisphenol A (TBBPA). However, high surface energy, self-agglomeration and low electron selectivity limit degradation rate and complete debromination of bare nZVI. Herein, we presented biomass-derived cellulose nanocrystals (CNC) modified nZVI (CNC/nZVI) for enhanced TBBPA removal. The effects of raw material (straw, filter paper and cotton), process (time, type and concentration of acid hydrolysis) and synthesis methods (in-situ and ex-situ) on fabrication of CNC/nZVI were systematically evaluated based on TBBPA removal performance. The optimized CNC-S/nZVI(in) was prepared via in-situ liquid-phase reduction using straw as raw material of CNC and processing through 44 % H2SO4 for 165 min. Characterizations illustrated nZVI was anchored to the active sites at CNC interface through electrostatic interactions, hydrogen bonds and FeO coordinations. The batch experiments showed 0.5 g/L CNC-S/nZVI(in) achieved 96.5 % removal efficiency at pH = 7 for 10 mg/L initial TBBPA. The enhanced TBBPA dehalogenation by CNC-S/nZVI(in), involving in initial adsorption, reduction process and partial detachment of debrominated products, were possibly attributed to elevated pre-adsorption capacity and high-efficiency delivery of electrons synergistically. This study indicated that fine-tuned fabrication of CNC/nZVI could potentially be a promising alternative for remediation of TBBPA-contaminated aquatic environments.

Biomass RNA for the Controlled Synthesis of Degradable Networks by Radical Polymerization.

Nucleic acids extracted from biomass have emerged as sustainable and environmentally friendly building blocks for the fabrication of multifunctional materials. Until recently, the fabrication of biomass nucleic acid-based structures has been facilitated through simple crosslinking of biomass nucleic acids, which limits the possibility of material properties engineering. This study presents an approach to convert biomass RNA into an acrylic crosslinker through acyl imidazole chemistry. The number of acrylic moieties on RNA was engineered by varying the acylation conditions. The resulting RNA crosslinker can undergo radical copolymerization with various acrylic monomers, thereby offering a versatile route for creating materials with tunable properties (e.g., stiffness and hydrophobic characteristics). Further, reversible-deactivation radical polymerization methods, such as atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT), were also explored as additional approaches to engineer the hydrogel properties. The study also demonstrated the metallization of the biomass RNA-based material, thereby offering potential applications in enhancing electrical conductivity. Overall, this research expands the opportunities in biomass-based biomaterial fabrication, which allows tailored properties for diverse applications.

Combined orthodontic and orthognathic treatment with 3D-printing technique offers a precise outcome: A case report of two years followup.

INTRODUCTION AND IMPORTANCE: Precision Medicine and evidence-based clinical treatment approach are proposed worldwide in medical science nowadays. Orthodontic first approach (OFA) and Computer-aided surgical simulation (CASS) combined 3D-printing technique offered more chances for the doctors to obey the principle of Precision Medicine in the orthodontic and orthognathic approach. CASE PRESENTATION: We reported a 20-year-old patient, with skeletal Class III relationship and asymmetric mandible, was treated by OFA. And with the CASS combined 3D-Printing Technique, the presurgery simulation and 3D-printed surgery guiding splint and stable splint offered the Combined Orthodontic and Orthognathic Treatment (COOT) a powerful and accurate guiding. The results exhibited that the patient had a perfect maxilla and mandible relationship and significant improvement in profile. CLINICAL DISCUSSION: There is still a debate between "surgery first" (SF) and conventional OFA. In this study, we analyzed the trend of different approaches in the COOT, which was a team work and required mainly the collaboration of orthodontist and Orthognathic surgeon. This study showed the precision of the CASS could offer for the OFA to evoke people immersing in saving time in COOT. CONCLUSION: All of these indicated that CASS was a powerful and precise method for COOT, which could offer the patient an esthetic and stable result.

The Proteasome Inhibitor Bortezomib Inhibits Inflammatory Response of Periodontal Ligament Cells and Ameliorates Experimental Periodontitis in Rats.

BACKGROUND: Periodontitis is a chronic inflammatory disease initiated by bacteria and their virulence factors. Bortezomib (BTZ) is the first proteasome inhibitor for clinical treatment of malignancies. Its anticancer activity is accompanied by an anti-inflammatory effect. However, there are few reports about its anti-inflammatory effect and underlying mechanism in periodontal disease, especially on human periodontal ligament cells (hPDLCs), which are considered a promising cell-based therapy for treating periodontitis. METHODS: hPDLCs were treated with lipopolysaccharide (LPS) and pretreated with BTZ. mRNA and protein levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1ß, IL-6, and IL-8 were determined. The anti-inflammatory mechanism of BTZ was studied. Further, experimental rat periodontitis was induced with ligature and LPS injection, and simultaneously and locally treated with BTZ (three injections/week). Four weeks after treatment, microcomputed tomography, immunohistochemical, and histopathologic analyses were performed. RESULTS: Bortezomib administration at safe concentrations (≤1 nM) inhibited production of proinflammatory cytokines in LPS-stimulated hPDLCs via nuclear factor (NF)-kappa B, p38/extracellular signal-regulated kinase, and mitogen-activated protein kinase/activator protein-1 pathways. Moreover, in the LPS and ligature-induced periodontitis rat model, BTZ suppressed expression of TNF-α, IL-1ß, IL-6, and IL-8, reduced the ratio of receptor activator of NF-κB ligand/osteoprotegerin, and prevented alveolar bone absorption. CONCLUSION: These findings demonstrate the anti-inflammatory activity of BTZ against periodontal inflammatory response and present BTZ as a promising therapy for periodontal disease.

Rapid degradation of Congo red by molecularly imprinted polypyrrole-coated magnetic TiO2 nanoparticles in dark at ambient conditions.

A novel molecularly imprinted polymer (MIP)-coated magnetic TiO2 nanocomposite was prepared, using methyl orange (MO) as the dummy template and pyrrole as functional monomer, for degradation of Congo red (CR). The nanocomposite was characterized by Fourier transform infrared spectroscopy, thermo-gravimetric analysis, X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer. The imprinting efficiency of the imprinted nanoparticles was investigated by static binding test, and their degradation ability toward CR was also studied. Moreover, the effects of pH, temperature, dissolved oxygen and oscillation rate on degradation rate of CR were investigated. Results showed that the imprinted nanocomposite had higher adsorption ability for MO compared with the non-imprinted one. Moreover, it could degrade CR rapidly in dark at room temperature and atmospheric pressure and could be recycled easily by a magnet with a good reusability. A degradation mechanism was proposed according to LC-MS analysis of degradation products of CR. The new imprinted nanoparticles showed high catalytic activity at ambient conditions without light illumination and additional chemicals, and therefore, it can be potentially applied to the rapid, "green" and low-cost degradation of CR in industrial printing and dyeing wastewater.