Search

Nanostructured materials often exhibit unique physical properties, such as fast carrier transport, subwavelength optical waveguiding, and a high surface-area-to-volume ratio. When the size of a material is reduced to nanoscale dimensions, its physical and chemical properties can change dramatically. In addition, nanostructures offer exciting new opportunities for environmental applications. In this review, we aim to provide an up-to-date summary of recent research related to multifunctional TiO2-based inorganic and organic semiconductor nanomaterials, covering both their synthesis and applications. After a brief introduction of the definition and classification of TiO2-based inorganic and organic semiconductor nanomaterial structures, we discuss various application strategies, such as sewage treatment, heavy metal removal, and the oxidation of alcohols to the corresponding aldehydes. In our previous work, we fabricated a variety of TiO2-based hollow spheres using a diverse range of materials from inorganic semiconductors to organic semiconductors and applied these structures as photocatalysts. Further, the development of these nanostructures may enable numerous applications in the field of environmental technology.

Objectives: Acyclovir (ACV) is an antiviral drug, which requires frequent dosing regimen because of poor oral bioavailability and short half-life. In this study, ACV nanoparticles were formulated using ammonium methacrylates copolymers such as Eudragit RS 100 (Eud RS) and Eudragit RL 100 (Eud RL) to prolong release drug, and increase bioavailability. Methods: ACV loaded nanoparticles were prepared by the solvent replacement technique and then were characterized by particle size, distribution, entrapment efficiency, differential scanning calorimeter, transmission electron microscope, and in-vitro drug release. Results: It was found that as drug:polymer ratio changed from 1:2 to1:5, particle size and drug entrapment efficiency increased significantly. ACV– Eud RS loaded nanoparticles had a larger mean diameter of 363 nm in comparison to 200 nm of ACV- Eud RL nanoparticles. DSC results showed that in the prepared ACV-Eud RS nanoparticles, the drug was presented in the amorphous phase and may have been molecularly dispersed in the polymer matrix, but in the ACV-Eud RL nanoparticles, the drug was presented in the particles and homogeneously dispersed in the polymeric matrix. The entrapment efficiency of AVC-Eud RS nanoparticles was higher than that of ACV-Eud RL nanoparticles. In vitro drug release study showed that the ratios of released drug from ACV-Eud RS nanoparticles in the range from 58±3.8 to 62.9±4.6%, which was lower than those from ACV-Eud RL nanoparticles, in the range from 73.3±4.9 to 77.9±2.9%. The release was found to follow the Weibull model with a Fickian diffusion mechanism for both ACVEud RS and ACV- Eud RL nanoparticles. Conclusion: These results suggest that ACV nanoparticles based on Eud RS100 and Eud RL100 could prolong the release of the drug.

Yuxia Duan,1,2 Mengjing Zhao,2 Mengmeng Jiang,2 Zhi Li,1 Caifang Ni1 1Department of Interventional Radiology, The First Affiliated Hospital of Soochow University, Suzhou 215006, People’s Republic of China; 2Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, People’s Republic of ChinaCorrespondence: Caifang Ni Email caifangni@yeah.netBackground: Long noncoding RNAs (lncRNAs) can promote hepatocellular carcinoma (HCC) initiation and progression. In this report, we examined the role of lncRNA LINC02476 in HCC.Methods: The expression levels of different lncRNAs in HCC were explored using the TCGA database and lncRNA LINC02476 was selected for further study. The expression of LINC02476 in HCC tissues was determined by real-time PCR. The clinicopathological characteristics of HCC patients were analyzed relative to the expression of LINC02476.The expression of LINC02476 was downregulated in HCC cells using a lentiviral vector and different assays were performed to study cell growth, proliferation, invasion, apoptosis and the cell cycle. MiR-497 was selected as a miRNA that could interact with LINC02476 which was further tested by RNA immunoprecipitation. HMGA2 was selected as a possible target of miR-497, and their interaction was examined by a luciferase reporter assay.Results: LINC02476 expression was elevated in HCC cell lines and HCC tissues. When LINC02476 was downregulated, the growth and the invasion of HCC cells decreased in vitro and in vivo. LINC02476 negatively regulated the expression of miR-497 by acting as a ceRNA. HMGA2 was directly targeted and inhibited by miR-497.Conclusion: The results indicate that LINC02476 functions through the miR-497/HMGA2 axis and that it has a role in the growth and metastasis of HCC cells. Therefore,LINC02476 could be an interesting new molecular target in HCC therapies.Keywords: LINC02476, miR-497, HMGA2, hepatocellular carcinoma

There is a strong need to develop MRI contrast agents (CAs) with lower in-vivo retention, stronger signal enhancement, and more specific imaging. Here, we report a novel dextran (DEX)-based nanomicelle system as an MRI CA with superior tumor imaging and relatively short intravascular persistence. Gadolinium (Gd)-chelate (DTPA-Gd) was conjugated directly to DEX hydroxyl via a degradable ester bond. DEX-DTPA-Gd was then modified with dodecylsuccinic anhydride to obtain the amphiphilic derivative, 2-dodecylsuccinic acid (DSA)-grafted DEX-DTPA-Gd. Nanomicelles were prepared by dissolving DSA-DEX-DTPA-Gd in water using ultrasonication. The physicochemical properties, cytotoxicity, and MRI efficiency of the synthesized CA were evaluated. The synthesized DSA-DEX-DTPA-Gd self-assembled into nanomicelles with an average diameter of 67.80 ± 5.21 nm. Within the given Gd concentration range, DSA-DEX-DTPA-Gd and Magnevist® exhibited similar cytotoxicity. DEX-based CAs resulted in a greater contrast enhancement of T1-weighted signal intensity in the tumor region than Magnevist®, and the tumors were clearly defined for at least 3 h. Simultaneously, the ester bond in DSA-DEX-DTPA-Gd facilitated the elimination of Gd chelates, compared with the relatively more stable amide linker. The DEX-based nanomicelle system with directly ester-bound DTPA-Gd may serve as an MRI CA with superior tumor imaging and relatively rapid elimination.

In this paper, we present novel integrable symplectic maps, associated with ordinary difference equations, and show how they determine, in a remarkably diverse manner, the integrability, including Lax pairs and the explicit solutions, for integrable partial difference equations which are the discrete counterparts of integrable partial differential equations of Korteweg‐de Vries‐type (KdV‐type). As a consequence it is demonstrated that several distinct Hamiltonian systems lead to one and the same difference equation by means of the Liouville integrability framework. Thus, these integrable symplectic maps may provide an efficient tool for characterizing, and determining the integrability of, partial difference equations.