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971.
Li-Jun Deng Yan-Lin Wu Xian-Hua He Ke-Nan Xie 《Journal of biomaterials science. Polymer edition》2013,24(18):2237-2251
AbstractA strategy developed for obtaining positive cellular responses remains to be focused in the filed of functional biomimetics. In this study, a hydrogel covered simvastatin-loaded polyetheretherketone (PEEK) bio-composites was constructed with the purpose of bone tissue regeneration therapy. Briefly, a three-dimensional (3D) porous structure was fabricated on PEEK surface; then the substrate was functionalized with the poly(L-lactic acid)/simvastatin porous film and hyaluronic acid hydrogel subsequently. In vitro cell attachment, proliferation, and cytoskeletal observation experiments reveal that our scaffolds show better bio-affinity due to the layer of hyaluronic acid hydrogel compared with control. Furthermore, the alkaline phosphatase activity, calcium mineral deposition evaluation, and gene expression for osteogenic potential all exhibit that the superior osteogenic differentiation of MC3T3-E1 pre-osteoblasts on our scaffolds. Therefore, our PEEK samples loaded with simvastatin and covered with hyaluronic acid hydrogel hold great potential in clinical applications for bone repair. 相似文献
972.
Drawing upon a sample of 772 migrant children and their parents in Shanghai, China, this study investigated how the interactions of social capital embedded in a range of social contexts (i.e., family, school, peer, and community) influenced the psychosocial adjustment of Chinese migrant children. Results of multiple‐group structural equation modeling revealed a moderating effect of community social capital on the associations between other dimensions of social capital and child psychosocial adjustment. Family social capital showed stronger effects when there was higher community social capital, while school social capital appeared to be most influential for children with lower community social capital. Peer social capital showed comparable effects on psychosocial adjustment regardless of the stock of community social capital, but was most important for children with limited resources in both the community and school. Implications of the research findings for theory, practice, policy and future research are discussed. © 2011 Wiley Periodicals, Inc. 相似文献
973.
Wen-Ni He Jun-Gui Dai Li-Jun Wu De-An Guo 《Journal of Asian natural products research》2013,15(9):760-764
Asiatic acid is a major pentacyclic triterpene isolated from Centella asiatica. It shows a variety of bioactivities. In order to obtain its derivatives, potentially useful for detailed pharmacological studies, the substrate was subjected to incubations with selected micro-organisms. In this work, asiatic acid was converted into three new compounds: 2α,3β,23,30-tetrahydroxyurs-12-ene-28-oic acid (1), 2α,3β,22β,23-tetrahydroxyurs-12-ene-28-oic acid (2), and 2α,3β,22β,23,30-pentahydroxyurs-12-ene-28-oic acid (3) by the fungus Alternaria longipes AS 3.2875. The structures of the three metabolites were determined by 1D and 2D NMR spectral data. 相似文献
974.
975.
976.
Caiyun He Huakang Tu Liping Sun Qian Xu Yuehua Gong Jingjing Jing Nannan Dong Yuan Yuan 《Oncotarget》2015,6(22):19017-19026
A series of host genes that respond to Helicobacter pylori (H. pylori) infection are involved in the process of gastric carcinogenesis. This study sought to examine interactions among polymorphisms of H. pylori-related genes PGC, PTPN11, TLR4, and IL1B and assess whether their interaction effects were modified by H. pylori infection. Thirteen polymorphisms of the aforementioned genes were genotyped by the Sequenom MassARRAY platform in 714 gastric cancer patients, 907 atrophic gastritis cases and 1276 healthy control subjects. When we considered the host genetic effects alone, gene–gene interactions consistently decreased the risks of gastric cancer and/or atrophic gastritis, including three two-way interactions: PGC rs6912200-PTPN11 rs12229892, PGC rs4711690-IL1B rs1143623 and PTPN11 rs12229892-IL1B rs1143623 and a three-way interaction: PGC rs4711690-PGC rs6912200-PTPN11 rs12229892. When the effect modification of H. pylori infection was evaluated, the cumulative effects of the aforementioned three-way interaction on atrophic gastritis susceptibility switched from being beneficial to being risky by the status of H. pylori infection. These data showed that SNP interactions among H. pylori-related genes PGC, PTPN11, and IL1B, are associated with susceptibility to gastric carcinogenesis. Moreover, we provided important hints of an effect modification by H. pylori infection on the cumulative effect of PGC and PTPN11 polymorphisms. Functional experiments and further independent large-scale studies especially in other ethnic populations are still needed to confirm our results. 相似文献
977.
978.
Xiaowei Peng Peiguo Cao Dong He Shuang Han Jianda Zhou Guolin Tan Wei Li Fenghui Yu Jianjun Yu Zan Li Ke Cao 《International journal of clinical and experimental pathology》2014,7(10):6784-6791
Resistance to chemotherapy is one of the key causal factors in cancer death and increasing evidence has revealed that microRNAs (miRNAs) are involved in chemoresistance in many kinds of human cancers. Paclitaxel has been used for treatment of advanced nasopharyngeal carcinoma (NPC); however, treatment failure often occurs due to development of acquired paclitaxel resistance. In this study, based on miRNA microarray screening and qRT-PCR validation, we found six differentially expressed miRNAs in our induced paclitaxel-resistant NPC CNE-1/Taxol cells. Furthermore, we clarified the role of miR-634, most significantly downregulated in the paclitaxel-resistant CNE-1/Taxol, in regulating the paclitaxel sensitivity in NPC cells. We restored miR-634 expression in the CNE-1/Taxol cells by lentivirus infection, and found restoration of miR-634 re-sensitized the CNE-1/Taxol cells to paclitaxel in vitro by MTT assay and colony formation assay. In xenograft mouse model, we found that miR-634 inhibited tumor growth and enhanced paclitaxel sensitivity. Thus, our findings provide important information for the development of targeted gene therapy for reversing paclitaxel resistance in NPC. 相似文献
979.
Yilong Zhang He Yan Guiying Wei Shitong Han Yufu Huang Qingfeng Zhang Weiqing Pan 《Antimicrobial agents and chemotherapy》2014,58(1):237-246
Southeast Asia (the Thailand-Cambodia border) has been considered the primal epicenter for most antimalarial drug resistance; however, numerous molecular epidemiological studies have successively reported multiple independent origins of sulfadoxine-pyrimethamine (SP) resistance-associated Plasmodium falciparum
dhfr (pfdhfr) and pfdhps alleles in other areas. To better understand the origin and evolutionary pathway of the SP resistance in Southeast Asia, a total of 374 P. falciparum field isolates from the Yunnan-Burma border and Hainan Island in southern China have been collected for comprehensive investigations on the mutation patterns of the pfdhfr/pfdhps genes as well as their microsatellite haplotypes. By comparative analysis of single-nucleotide polymorphism (SNP) genotyping and flanking microsatellite haplotypes, we reveal a unique origin of pyrimethamine-resistant mutations in Pfdhfr gene in Hainan Island and an oriented spread route of the pyrimethamine resistance from the Thailand-Cambodia border into the Hainan area, which reflects the geographical traits and SP administration histories in the two geographically independent areas. Moreover, genetic linkages between the high-level SP resistance-conferring pfdhfr/pfdhps alleles have been established in the isolates from the Yunnan-Burma border, raising the concern of a genetic basis in adopting combination chemotherapies against falciparum malaria. 相似文献
980.