Discovery and in Vivo Evaluation of Novel RGD-Modified Lipid-Polymer Hybrid Nanoparticles for Targeted Drug Delivery

In the current study, the lipid-shell and polymer-core hybrid nanoparticles (lpNPs) modified by Arg–Gly–Asp(RGD) peptide, loaded with curcumin (Cur), were developed by emulsification-solvent volatilization method. The RGD-modified hybrid nanoparticles (RGD–lpNPs) could overcome the poor water solubility of Cur to meet the requirement of intravenous administration and tumor active targeting. The obtained optimal RGD-lpNPs, composed of PLGA (poly(lactic-co-glycolic acid))–mPEG (methoxyl poly(ethylene- glycol)), RGD–polyethylene glycol (PEG)–cholesterol (Chol) copolymers and lipids, had good entrapment efficiency, submicron size and negatively neutral surface charge. The core-shell structure of RGD–lpNPs was verified by TEM. Cytotoxicity analysis demonstrated that the RGD–lpNPs encapsulated Cur retained potent anti-tumor effects. Flow cytometry analysis revealed the cellular uptake of Cur encapsulated in the RGD–lpNPs was increased for human umbilical vein endothelial cells (HUVEC). Furthermore, Cur loaded RGD–lpNPs were more effective in inhibiting tumor growth in a subcutaneous B16 melanoma tumor model. The results of immunofluorescent and immunohistochemical studies by Cur loaded RGD–lpNPs therapies indicated that more apoptotic cells, fewer microvessels, and fewer proliferation-positive cells were observed. In conclusion, RGD–lpNPs encapsulating Cur were developed with enhanced anti-tumor activity in melanoma, and Cur loaded RGD–lpNPs represent an excellent tumor targeted formulation of Cur which might be an attractive candidate for cancer therapy.     

强化化工专业本科生计算机应用能力培养

以武汉科技大学化学工程与技术学院化学工程与工艺专业为例,介绍了优化培养计划、在专业理论教学中融入计算机应用和在实践教学强中融入计算机应用等强化化工专业本科生计算机应用能力培养的具体措施。指出化工专业本科生计算机应用能力的培养是一项系统工程,光靠低年级开设的那几门计算机课程是不够的,在高年级阶段还要继续强化计算机应用能力的培养。     

1,2,3,3,3-五氟丙烯的合成

介绍了1,2,3,3,3-五氟丙烯的性质和应用,综述了1,2,3,3,3-五氟丙烯的合成方法,分析了各合成工艺的优缺点,认为以HFP或卤代甲烷和卤代乙烯为原料合成1,2,3,3,3-五氟丙烯具有工业化前景,并指出加快1,2,3,3,3-五氟丙烯的应用研究对丰富我国ODS替代品的种类有重要意义。     

Pt promotional effects on Pd–Pt alloy catalysts for hydrogen peroxide synthesis directly from hydrogen and oxygen

H₂O₂ synthesis directly from H₂ and O₂ over supported Pd–Pt alloy catalysts was carried out using a semibatch reactor under ambient conditions. As compared to pure Pd, the performance of Pd–Pt catalysts was enhanced significantly. The promotional role of Pt was studied systematically by using in situ diffuse reflectance infrared Fourier transform spectroscopy of CO adsorption (DRIFTS), quantitative powder X-ray diffraction (XRD), X-rays photoelectron spectroscopy (XPS), and temperature-programmed desorption of H₂/O₂ (H₂/O₂-TPD). The spectra of DRIFT, XPS, and XRD demonstrate the formation of Pd–Pt alloy particles, which surfaces are enriched by Pt accompanying with possible electron transfer from Pd to Pt. The addition of Pt into Pd phase was proposed to impact on reactants adsorption, stabilization of intermediates such as OOH and OH radicals, and the formation and decomposition of H₂O₂.     

Hepatic differentiation of rat mesenchymal stem cells by a small molecule

Mesenchymal stem cells (MSCs) are capable of self-renewal and multilineage differentiation. A periodic acid-Schiff (PAS) stain-based assay was developed to screen for small-molecule inducers of hepatic differentiation of bone marrow MSCs. 2-(4-Bromophenyl)-N-(4-fluorophenyl)-3-propyl-3H-imidazo[4,5-b]pyridin-5-amine (SJA710-6) was identified as a novel small molecule able to induce the differentiation of rat MSCs (rMSCs) toward hepatocyte-like cells in vitro, where rMSCs treated with SJA710-6 have typical morphological and functional characteristics of hepatic cells, including glycogen storage, urea secretion, uptake of low density lipoprotein (LDL) and expression of hepatocyte-specific genes and proteins. Expression of FoxH1 (FAST1/2) induces the differentiation of rMSCs towards hepatocyte-like cells, suggesting that this gene plays an important role in the hepatic fate specification of rMSCs.     

Theoretical Prediction of the Structure and Properties of Cubic Spinel Nitrides

The structure and properties of cubic spinel nitrides were investigated based on first-principles theoretical calculations. The lattice constants, bulk moduli, band structures, electronic bonding, and lattice stability of thirty-nine single and double nitrides were studied. The single spinel nitrides of the form c -A₃N₄ (where A is a Group IVA element), except c -Hf₃N₄, are all semiconductors with band gaps ranging from an indirect gap of 0.07 eV in c -Ti₃N₄ to a direct gap of 3.45 eV in c -Si₃N₄. For double nitrides of the form c -AB₂N₄ (where A and B are Group IVA (Ti, Zr, Hf) or IVB (C, Si, Ge, Sn) elements), both metallic and insulating band structures are possible. The stability of the double spinel nitrides, relative to single nitrides, is dependent on the optimal cation radii and polyhedral volumes at the tetrahedral A sites and the octahedral B sites. Of the thirty-two double nitrides, only nine are predicted to be energetically favorable. Among the potentially stable phases, the most interesting ones are c -CSi₂N₄ (which has an exceptionally strong covalent bonding and large bulk modulus), c -SiGe₂N₄ (which has an energetically favorable direct band gap of 1.85 eV), and c -SiTi₂N₄ (which is metallic).     

镁质复合滑板的研制和使用

研究了镁砂及烧成温度对镁质滑板高温性能的影响。结果表明 :以ω(MgO)≥ 98%、C/S≥ 3、晶粒直径≥ 5 0 0 μm的高纯镁砂为内层料 ,以中低档镁砂为外层料 ,用纸浆废液作结合剂 ,直接复合成型的镁质滑板经 16 5 0℃左右的高温烧成后 ,性能指标达到外商订货要求 ,不经浸油、打箍 ,在国外 385t连铸钢包批量试用成功。     

Design of S‐Allylcysteine in Situ Production and Incorporation Based on a Novel Pyrrolysyl‐tRNA Synthetase Variant

The noncanonical amino acid S‐allyl cysteine (Sac) is one of the major compounds of garlic extract and exhibits a range of biological activities. It is also a small bioorthogonal alkene tag capable of undergoing controlled chemical modifications, such as photoinduced thiol‐ene coupling or Pd‐mediated deprotection. Its small size guarantees minimal interference with protein structure and function. Here, we report a simple protocol efficiently to couple in‐situ semisynthetic biosynthesis of Sac and its incorporation into proteins in response to amber (UAG) stop codons. We exploited the exceptional malleability of pyrrolysyl‐tRNA synthetase (PylRS) and evolved an S‐allylcysteinyl‐tRNA synthetase (SacRS) capable of specifically accepting the small, polar amino acid instead of its long and bulky aliphatic natural substrate. We succeeded in generating a novel and inexpensive strategy for the incorporation of a functionally versatile amino acid. This will help in the conversion of orthogonal translation from a standard technique in academic research to industrial biotechnology.     

An analytical model of nanopatterned superhydrophobic surfaces

Wetting behaviors on a hydrophobic nanopatterned surface, which are of primary consideration in the design of superhydrophobic surfaces, are studied on an analytic model that shows the hole-patterned substrate is more favorable for water droplets to nucleate on the inside of holes based on nucleation theory. After droplet nucleation, the transition from Wenzel state to Cassie–Baxter state may occur during the growth stage. The calculation of the free energy of droplets during the growth stage indicates that the wetting transitions depend on the volume of the droplets, and Wenzel state or Cassie–Baxter state depends on the absolute size and relative size of the geometrical morphology of the nanoholes.