Effective delivery is the primary barrier against the clinical translation of gene therapy. Yet there remains too much unknown in the gene delivery mechanisms, even for the most investigated polymeric carrier (i.e., PEI). As a consequence, the conflicting results have been often seen in the literature due to the large variability in the experimental conditions and operations. Therefore, some key parameters should be identified and thus strictly controlled in the formulation process. Methods : The effect of the formulation processing parameters (e.g., concentration or mixture volume) and the resulting nanostructure properties on gene transfection have been rarely investigated. Two types of the PEI/DNA nanoparticles (NPs) were prepared in the same manner with the same dose but at different concentrations. The microstructure of the NPs and the transfection mechanisms were investigated through various microscopic methods. The therapeutic efficacy of the NPs was demonstrated in the cervical subcutaneous xenograft and peritoneal metastasis mouse models. Results : The high-concentration process (i.e., small reaction-volume) for mixture resulted in the large-sized PEI/DNA NPs that had a higher efficiency of gene transfection, compared to the small counterpart that was prepared at a low concentration. The microstructural experiments showed that the prepared small NPs were firmly condensed, whereas the large NPs were bulky and botryoid-shaped. The large NPs entered the tumor cells via the macropinocytosis pathway, and then efficiently dissociated in the cytoplasm and released DNA, thus promoting the intranuclear delivery. The enhanced in vivo therapeutic efficacy of the large NPs was demonstrated, indicating the promise for local-regional administration. Conclusion : This work provides better understanding of the effect of formulation process on nano-structural properties and gene transfection, laying a theoretical basis for rational design of the experimental process.

An overlap titanium-on-aluminum configuration based on laser penetration welding was designed to suppress the formation of intermetallic compounds. Weld surface appearance, weldgeometry, microstructure, and mechanical property of the joint were investigated. The collaps of upper liquid titanium closes keyhole filled with boiling aluminum vapor, which induces welding spatter. Optimizing processing parameters could control the welding spatter to some extent. Weld geometry is characterized by depth of the weld loss, depth of the penetration of titanium into aluminum and width of joining, which depends on processing parameters strongly. The overlap titanium-on-aluminum configuration can suppress the formation of intermetallic compounds inside Ti weld. Interfacial reaction appears between Ti weld and Al, and the reaction layers are composed of TiAl and TiAl 3 . The banded structures with Ti 3 Al were found inside Ti weld. Tensile capacity of the joint increases firstly and then decreases with increasing laser power or decreasing welding speed, depending on weld geometry and interfacial reaction. Moreover, there are two broken modes of the joints, which are fractured in interface and in Ti weld, respectively. When joints fracture in the Ti weld, the joint has the higher tensile property, up to 184 N/mm.

Background microRNAs (miRNAs) play important roles in abnormal proliferation and migration of vascular smooth muscle cells (VSMCs), which lead to restenosis in coronary artery disease. Nevertheless, the role of miR-18a-5p and how it works in VSMCs remain unknown. Material/Methods miR-18a-5p expression was determined by fluorescence quantitative real-time polymerase chain reaction (qRT-PCR) analysis of tissues from 20 patients with stent restenosis, and rats with carotid artery injury, as well as VSMCs. A cell viability assay was used to measure cell proliferation. Cell migration abilities were assessed by transwell migration assay and wound healing assays. To identify miR-18a-5p targets, a dual-luciferase reporter assay was performed. Western blot analysis and immunofluorescence techniques were used to assess the protein expression levels of AKT and ERK. The rescue effects of miR-18a-5p on the proliferation or migration of VSMCs were evaluated after exposure to the AKT inhibitor MK-2206 and ERK inhibitor PD98059. Results The expression level of miR-18a-5p was significantly higher in the blood serum of patients with stent restenosis and in rats with carotid artery injury, and the expression of AKT and ERK was higher after carotid artery injury. The proliferation and migration abilities of VSMCs were accelerated by the overexpression of miR-18a-5p. It was found that miR-18a-5p directly modulates AKT/ERK signaling. Upregulated miR-18a-5p increased the protein expression levels of AKT and ERK and we found a positive correlation between miR-18a-5p expression level and expression of AKT and ERK. Additionally, the promoting effect of miR-18a-5p on VSMCs proliferation, migration, and invasion was reversed by ERK inhibitor or AKT inhibitor. Conclusions miR-18a-5p can promote proliferation of VSMCs by activating the AKT/ERK signaling pathway.

A series of novel chromeno[4,3-c]pyrazol-4(2H)-one containing carbonyl or oxime derivatives (4a-n, 5a-n) have been synthesized and evaluated their biological activities as phosphatidyl inositol 3-kinase (PI3K) inhibitors. Out of them, compound 5l showed the most potent antiproliferative activities against HCT-116 with IC 50 of 0.10 µM in vitro, and exhibited the most potent activity for PI3Kα with the value of 0.012 µM. Docking simulation of 5l into PI3Kα active site were performed to determine the probable binding model, and it indicated that compound 5l could be optimized as a potential inhibitor of PI3Kα in the further study. Key words chromeno[4,3-c]pyrazol-4(2H)-one derivative; inhibitor; antiproliferativeThree distinct classes of lipid phosphatidyl inositol 3-kinases (PI3Ks), as a family, play a key role in cellular processes by regulating functions such as cell metabolism, proliferation, differentiation, motility, and intracellular trafficking.