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41.
Enterovirus 71 (EV71) is a highly infectious major causative agent of hand, foot, and mouth disease (HFMD) which could lead to severe neurological complications. There is currently no effective therapy against EV71. In this study, RNA interference (RNAi) is employed as a therapeutic approach for specific viral inhibition. Various regions of the EV71 genome were targeted for inhibition by chemically synthesized siRNAs. Transfection of rhabdomyosarcoma (RD) cells with siRNA targeting the 3'UTR, 2C, 3C, or 3D region significantly alleviated cytopathic effects of EV71. The inhibitory effect was dosage-dependent with a corresponding decrease in viral RNA, viral proteins, and plaque formations by EV71. Viral inhibition of siRNA transfected RD cells was still evident after 48 h. In addition, no significant adverse off-target silencing effects were observed. These results demonstrated the potential and feasibility for the use of siRNA as an antiviral therapy for EV71 infections. 相似文献
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Transfection of human macrophages by lipoplexes via the combined use of transferrin and pH-sensitive peptides 总被引:10,自引:0,他引:10
Simões S Slepushkin V Pretzer E Dazin P Gaspar R Pedroso de Lima MC Düzgüneş N 《Journal of leukocyte biology》1999,65(2):270-279
The crucial function of macrophages in a variety of biological processes and pathologies render these cells important targets for gene therapeutic interventions. Commonly used synthetic gene delivery vectors have not been successful in transfecting these non-dividing cells. A combination strategy involving cationic liposomes to condense and carry DNA, transferrin to facilitate cellular uptake, and the pH-sensitive peptide GALA to promote endosome destabilization, resulted in significant expression of a luciferase gene. Transfection of macrophages was dependent on the degree of differentiation of the cells. The quaternary complexes of cationic liposomes, DNA, transferrin, and GALA exhibited a net negative charge, which may obviate a limitation of cationic synthetic vectors in vivo. The lack of cytotoxicity and the expected lack of immunogenicity of these complexes may render them useful for gene delivery to macrophages in vivo. 相似文献
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Park SJ Kim YC Suh SH Rhim H Sim JH Kim SJ So I Kim KW 《The Japanese journal of physiology》2000,50(6):635-643
The ion channel conductances that regulate the membrane potential was investigated by using a perforated patch-clamp technique in rabbit aorta endothelial cells (RAECs). The whole-cell current/voltage (I-V) relation showed a slight outward rectification under physiological ionic conditions. The resting membrane potential was -23.3 +/- 1.1 mV (mean +/- SEM, n = 19). The slope conductances at the potentials of -80 and 50 mV were 31.0 +/- 4.0 and 62.8 +/- 7.1 pS pF(-1), respectively (n = 15). Changes in the extracellular and intracellular Cl(-) concentrations did not affect the reversal potential on I-V curves. The background nonselective cationic (NSC) current was isolated after the K(+) current was suppressed. The relative permeabilities calculated from the changes in reversal potentials using the constant-field theory were P(K):P(Cs):P(Na):P(Li) = 1:0.87:0.40:0.27 and P(Cs):P(Ca) = 1:0.21. Increases in the external Ca(2+) decreased the background NSC current in a dose-dependent manner. The concentration for half block by Ca(2+) was 1.1 +/- 0.3 mM (n = 7). Through the continuous recording of the membrane potential in a current-clamp mode, it was found that the background NSC conductance is the major determinant of resting membrane potential. Taken together, it could be concluded that the background NSC channels function as the major determinant for the resting membrane potential and can be responsible for the background Ca(2+) entry pathway in freshly isolated RAECs. 相似文献
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A study of 28 patients receiving a standard regimen of total intravenous nutrition (I.V.N.) for periods of > 14 days has shown the transient development of hypercalciuria in 14 patients (50%). The peak incidence of hypercalciuria occurred in 11 patients (39%) after 1 week of I.V.N. and hypercalciuria persisted for 1–4 weeks. In only one patient was hypercalciuria present at the end of the treatment period. Urine calcium (Ca) and nitrogen (N) excretion rates correlated significantly (r = 0.48 p<0.001) and urine N excretion varied from week to week in parallel with urine Ca excretion in the hypercalciuric group of patients. There was no significant difference in urine Ca excretion between 12 patients who received 3.75 mmol Ca/day and 16 patients who received 8.75 mmol Ca/day. It is concluded that transient hypercalciuria may be related to increased protein catabolism and N excretion and that it probably does not indicate a major problem in mineral metabolism. 相似文献
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A rapid isotachophoretic separation of benzo[ C]phenanthridine alkaloids from CHELIDONIUM MAJUS L. is described. The method allows the determination of sanguinarine and chelerythrine in the presence of other isoquinoline alkaloids in crude alkaloids extracts. 相似文献
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Joanna Rees Simone Radavelli Bagatini Johnny Lo Jonathan M. Hodgson Claus T. Christophersen Robin M. Daly Dianna J. Magliano Jonathan E. Shaw Marc Sim Catherine P. Bondonno Lauren C. Blekkenhorst Joanne M. Dickson Joshua R. Lewis Amanda Devine 《Nutrients》2021,13(5)
Increasing prevalence of mental health disorders within the Australian population is a serious public health issue. Adequate intake of fruits and vegetables (FV), dietary fibre (DF) and resistant starch (RS) is associated with better mental and physical health. Few longitudinal studies exist exploring the temporal relationship. Using a validated food frequency questionnaire, we examined baseline FV intakes of 5845 Australian adults from the AusDiab study and estimated food group-derived DF and RS using data from the literature. Perceived mental health was assessed at baseline and 5 year follow up using SF-36 mental component summary scores (MCS). We conducted baseline cross-sectional analysis and prospective analysis of baseline dietary intake with perceived mental health at 5 years. Higher baseline FV and FV-derived DF and RS intakes were associated with better 5 year MCS (p < 0.001). A higher FV intake (754 g/d vs. 251 g/d, Q4 vs. Q1) at baseline had 41% lower odds (OR = 0.59: 95% CI 0.46–0.75) of MCS below population average (<47) at 5 year follow up. Findings were similar for FV-derived DF and RS. An inverse association was observed with discretionary food-derived DF and RS. This demonstrates the association between higher intakes of FV and FV-derived DF and RS with better 5 year mental health outcomes. Further RCTs are necessary to understand mechanisms that underlie this association including elucidation of causal effects. 相似文献