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991.
992.
Qiwen Wang Weihong Jin Guosong Wu Ying Zhao Xue Jin Xiurong Hu Jun Zhou Guping Tang Paul K. Chu 《Biomaterials》2014
Cationic polymer PEI-CyD is doped with Nd by plasma technology to produce the gene vector: Nd@PEI-CyD. Luciferase expression and EGFP transfection experiments performed in vitro reveal that Nd@PEI-CyD has significantly higher transfection efficiency than lipofectamine 2000 and PEI-CyD and the mechanism is studied and proposed. The rare-earth element, Nd, stimulates the energy metabolism of cells, enhances cell uptake of complexes/pDNA, and regulates the cellular pathways. These special features suggest a new strategy involving metal-incorporated non-viral gene vectors. 相似文献
993.
Yuta Yoshizaki Eiji Yuba Naoki Sakaguchi Kazunori Koiwai Atsushi Harada Kenji Kono 《Biomaterials》2014
Cationic lipid-incorporated liposomes modified with pH-sensitive polymers were prepared by introducing 3, 5-didodecyloxybenzamidine as a cationic lipid to egg yolk phosphatidylcholine liposomes modified with 3-methylglutarylated hyperbranched poly(glycidol) (MGlu-HPG) as a pH-sensitive polymer. These liposomes were stable at neutral pH, but were destabilized below pH 6.0 because MGlu-HPG changed its characteristics from hydrophilic to hydrophobic in response to the pH decrease. Cationic lipid inclusion improved their pH sensitivity at weakly acidic pH and association of liposomes with murine dendritic cell (DC) lines. Cationic lipid-incorporated liposomes delivered entrapped ovalbumin (OVA) molecules not only to cytosol but also to endosome/lysosome. Treatment with cationic lipid-incorporated liposomes induced up-regulation of antigen presentation-involved molecules on DCs, the promotion of cytokine production, and antigen presentation via both major histocompatibility complex (MHC) class I and II molecules. Especially, antigen presentation via MHC class II was promoted by cationic lipid inclusion, which might correspond to efficient endosome/lysosome delivery of OVA. Subcutaneous administration of OVA-loaded cationic lipid-incorporated liposomes induced antigen-specific antibody production in serum and Th1-dominant immune responses in the spleen. Furthermore, administration of the cationic lipid-incorporated liposomes to mice bearing E.G7-OVA tumor more significantly reduced the tumor volume than liposomes without cationic lipids. Therefore, cationic lipid inclusion into pH-sensitive polymer-modified liposomes, which can achieve both efficient antigen intracellular delivery and activation of antigen presenting cell, is an effective approach to develop antigen carriers for efficient cancer immunotherapy. 相似文献
994.
Bartholomew I C Brai Rahmat A Adisa Adebimpe A Odetola 《African journal of traditional, complementary, and alternative medicines》2014,11(2):237-244
Background
Natural products from plants have received considerable attention in recent years due to their diverse pharmacological properties, including antioxidants and hepatoprotective activities. The protective effects of aqueous extract of Persea americana (AEPA) against carbon tetrachloride (CCl4)-induced hepatotoxicity in male albino rats was investigated.Materials and Methods
Liver damage was induced in rats by administering a 1:1 (v/v) mixture of CCl4 and olive oil [3 ml/kg, subcutaneously (sc)] after pre-treatment for 7 days with AEPA. Hepatoprotective effects of AEPA was evaluated by estimating the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and levels of total bilirubin (TBL). The effects of AEPA on biomarkers of oxidative damage (lipid peroxidation) and antioxidant enzymes namely, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were measured in liver post mitochondrial fraction.Results
AEPA and Reducdyn® showed significant (p<0.05) hepatoprotective activity by decreasing the activities of ALT, AST, ALP and reducing the levels of TBL. The activities of antioxidant enzymes, levels of malondialdehyde and protein carbonyls were also decreased dose-dependently in the AEPA-treated rats. Pre-treatment with AEPA also decreased the serum levels of glutathione significantly.Conclusion
These data revealed that AEPA possesses significant hepatoprotective effects against CCl4-induced toxicity attributable to its constituent phytochemicals. The mechanism of hepatoprotection seems to be through modulation of antioxidant enzyme system. 相似文献995.
Ngozi Paulinus Okolie Abiodun Falodun Oluseyi Davids 《African journal of traditional, complementary, and alternative medicines》2014,11(3):221-227
Background
The antioxidant properties of ethanolic root extract of pepper fruit (Donnetia tripetala), and its effect on lipid peroxidation of some fresh beef tissues during frozen storage were investigated.Materials and Methods
The antioxidant parameters were assessed using standard methods, while malondialdehyde levels of different fresh beef tissue sections treated with the extract prior to freezing, were estimated in a colorimetric reaction with thiobarbituric acid.Results
The H2O2-scavenging ability of the extract was similar to that of ascorbic acid, with a maximum scavenging power of 55.61 ±4.98%, and an IC50 value of 86µg/ml. The extract exhibited a concentration-dependent ferric ion-reducing power, although this was significantly lower relative to that of the ascorbic acid (p < 0.05). The total phenolic content was 212.5 ± 0.002 mg/g, while the nitric oxide-scavenging ability was 64.33 ± 0.2% after 150 min. The capacity of the extract to inhibit lipid peroxidation in frozen heart muscle slices was significantly higher than that of vitamin C (p < 0 .05), but comparable to vitamins C and E in frozen testes and kidney slices.Conclusion
These results suggest that the root extract of D. tripetala is rich in antioxidants which can be applied to meat preservation during refrigerated storage. 相似文献996.
目的探讨影响健康孕妇新生儿体重的相关因素。方法本研究为前瞻性研究,选择2013年3-8月在青岛市市立医院检查并决定在本院分娩的早孕妇女480例,排除个别妊娠合并症和并发症,共376例进入研究,追踪调查至孕妇分娩。详细记录孕妇年龄、孕前体质量、身高、分娩孕周、分娩前体质量、孕期体质量增长、新生儿体质量,并检测妊娠32~34周孕妇血脂及血糖水平,分析各因素与新生儿体质量的相关性。结果孕期体质量增长、甘油三酯水平与新生儿体质量呈正相关(r=0.213,P〈0.01;r=0.244,P〈0.001)。甘油三酯与孕前体重指数、孕期体质量增长呈正相关(r=0.172,P〈0.05;r=0.178,P〈0.01)。巨大儿组孕妇甘油三酯水平为(3.82±1.47)mmol/L,正常儿组孕妇为(3.21±1.26)mmol/L,差异有统计学意义(P〈0.05)。巨大儿组孕妇空腹血糖水平为(4.45±0.063)mmol/L,正常儿组孕妇血糖水平为(4.17±0.50)mmol/L,差异有统计学意义(P〈0.01)。结论孕妇血脂、血糖水平及孕期增重显著影响新生儿出生体重,孕期应该平衡膳食、合理增重,并进行血脂、血糖监测,对控制新生儿的体重有重要的临床意义。 相似文献
997.
Tsung-Hsien Lin Shao-Yuan Chuang Chun-Yuan Chu Wen-Hsien Lee Po-Chao Hsu Ho-Ming Su Yi-Heng Li Ching-Chang Fang Kuo-Yang Wang Wei-Kung Tseng Ai-Hsien Li Kwo-Chang Ueng I-Chang Hsieh Lien-Chi Huang Chiun-Hsiung Wang Wen-Harn Pan Hung-I Yeh Chau-Chung Wu Wei-Hsian Yin Jaw-Wen Chen 《International journal of medical sciences》2014,11(4):381-388
Background: Patients with chronic kidney disease (CKD) is a very high risk cardiovascular disease population and should be treated aggressively. We investigated lipid management in CKD patients with atherosclerosis in Taiwan.Methods: 3057 patients were enrolled in a multi-center study (T-SPARCLE). Lipid goal are defined as total cholesterol (TC) < 160mg/dl, low-density lipoprotein (LDL) <100 mg/dl, high-density lipoprotein (HDL) > 40 mg/dl in men, HDL > 50 mg/dl in women, non-HDL cholesterol < 130mg/dl, and triglyceride < 150 mg/dl.Results: Compared with those without CKD (n=2239), patients with CKD (n=818) had more co-morbidities (hypertension, glucose intolerance, stroke and heart failure) and lower HDL but higher triglyceride levels. Overall 2168 (70.5%) patients received lipid-lowering agents. There was similar equivalent statin potency between CKD and non-CKD groups. The goal attainment is lower in HDL and TG in the CKD group as compared with non-CKD subjects (47.1 vs. 51.9% and 63.2 vs. 68.9% respectively, both p < 0.02). Analysis of sex and CKD interaction on goals attainment showed female CKD subjects had lower non-HDL and TG goals attainment compared with non-CKD males (both p < 0.019).Conclusion: Although presenting with more comorbidities, the CKD population had suboptimal lipid goal attainment rate as compared with the non-CKD population. Further efforts may be required for better lipid control especially on the female CKD subjects. 相似文献
998.
《The Journal of pediatrics》2014,164(5):1128-1132.e1
999.