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Objective:To prepare pH-sensitive liposomes to avoid the degradation of monophosphoryl lipid A (MPLA) by lysosomes.Methods:Using DOPE and CHEMS as carrier materials, pH-sensitive liposomes were prepared by thin-film dispersion method. Particle sizes and Zeta potential of the liposomes were detected by dynamic light scattering. The morphological features of pH-sensitive liposomes under different pH conditions were observed by transmission electron microscopy. Flow cytometry was performed to detect the phagocytosis of liposomes by THP-1 and DC2.4 cells. Confocal laser microscopy was used to observed the colocalization of liposomes and lysosomes. BALB/c mice were immunized with hepatitis B surface antigen (HBsAg) using MPLA pH-sensitive liposome as an adjuvant. The levels of serum anti-HBs were quantitatively detected by ELISA. IFN-γ and IL-2 spot forming cells (SFCs) in mouse splenic lymphocytes were detected by ELISPOT.Results:The pH-sensitive liposomes were constructed with an average particle size of (90.90±1.13) nm, polydispersity index (PDI) of 0.076±0.013 and Zeta potential of (-27.900±0.666) mV. As the pH value of the solution decreased, the particle size increased significantly and the liposomes presented irregular shapes, indicating the pH-sensitive features. The phagocytosis rates by THP-1 cells and DC2.4 cells were 10.40% and 12.40% for pH-sensitive fluorescent liposomes, and 1.09% and 0.28% for fluorescent liposomes. Confocal laser microscopy revealed that pH-sensitive fluorescent liposomes were phagocytosed by THP-1 cells and existed in the cytoplasm, while fluorescent liposomes existed in lysosomes. Compared with MPLA liposomes, MPLA pH-sensitive liposomes could significantly improve the cellular immune response in mice. The levels of IFN-γ and IL-2 SFCs in the MPLA pH-sensitive liposome group were significantly higher than those in the MPLA liposome group ( P<0.01) and the non-adjuvant group ( P<0.001). Conclusions:The pH-sensitive liposome delivery system could improve the utilization of MPLA as an adjuvant.
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Objective:To express the recombinant varicella-zoster virus (VZV) gE Δ-Fc fusion protein using CHO cell expression system, and provide reference for screening candidate antigens of recombinant herpes zoster vaccines. Methods:A eukaryotic expression plasmid containing the gE Δ-Fc gene was transfected into CHO cells. Monoclonal cells were selected by methionine sulfoximine (MSX) pressure screening and limited dilution method to obtain the CHO cells secreting and expressing the gE Δ-Fc fusion protein. The expressed gE Δ-Fc fusion protein was purified by MabSelect SuRe affinity chromatography. The binding activity of gE Δ-Fc fusion protein to Fc receptors was identified by ELISA. Flow cytometry was used to detect the phagocytosis of antigens by DC2.4 cells. Antibody titers in serum samples of BALB/c mice immunized with the gE Δ-Fc fusion protein were detect by ELISA. Results:A CHO cell line stably expressing the gE Δ-Fc fusion protein was obtained. Flow cytometry suggested that the phagocytotic activity of DC2.4 cells against the gE Δ-Fc fusion protein was stronger than that against gE. Moreover, the gE Δ-Fc fusion protein could induce BALB/c mice to produce high titers of specific anti-VZV antibodies. Conclusions:The recombinant VZV gE Δ-Fc fusion protein expressed in CHO cells had a good immunogenicity. This study provided reference for screening candidate antigens of recombinant herpes zoster vaccines.
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Objective To evaluate the immunogenicity of an immune complexed hepatitis B vac-cine ( HBsAg-HBIG immune complexes , IC) in mouse and cynomolgus monkeys by using recombinant hepa-titis B vaccine ( Saccharomyces cerevisiae, HBsAg) as the control .Methods BALB/c mice were vaccinated with single dose of IC and single dose of HBsAg respectively and then serum samples were collected at differ -ent time points for the detection of dynamic anti-HBs by using ELISA .The serum anti-HBs titers in BALB/c mice vaccinated with different immunization strategies were also analyzed .ELISPOT assay was performed to detect the numbers of IFN-γSFC and IFN-γpositive rate in splenocytes of BALB/c mice intramuscularly im-munized with IC, HBsAg or standard hepatitis B vaccine at 5μg/mouse.ED50 was measured to evaluate the stability of IC.Twelve cynomolgus monkeys were equally divided into two groups and immunized with high dose (100 μg) and low dose (20 μg) of IC respectively and then , serum anti-HBs levels at different time points were detected .Results The serum anti-HBs titers in IC immunized group at different time points were higher than those immunized with HBsAg .Moreover, the anti-HBs titer induced by two doses of IC reached a level comparable to that elicited by three doses of HBsAg .ELISPOT assay showed that both the numbers of IFN-γSFC and IFN-γpositive rate were the highest in IC immunized group as compared with those immunized with HBsAg and standard hepatitis B vaccine .IC had a lower ED50 than HBsAg, indicating a good long term stability .Cynomolgus monkeys immunized with high or low dose of IC produced high levels of anti-HBs titer during a long time period .Conclusion IC has a higher immunogenicity inducing both hu-moral immunity and cellular immunity as compared with HBsAg or standard hepatitis B vaccine .
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Objective To evaluate the effect of different doses of aspirin on the platelet inhibition rate by thremboelastography.Methods One hundred and eighty patients with ischemic stroke or transient cerebral ischemic attack (TIA) were randomly divided into aspirin 100 mg/d group (60 patients),aspirin 200 mg/d group (60 patients) and aspirin 300 mg/d group (60 patients) according to the order of treatment.The platelet inhibition rate which arachidonic acid pathway induced was measured by thromboelastography and compared at different time points (before medication; 7 days,6 months,1 year after medication).Results There were significant differences in the platelet inhibition rate after medication at different time points compared with that before medication in three groups (P ＜ 0.05).After medication at different time points,the platelet inhibition rate of aspirin 100 mg/d group and aspirin 200 mg/d group was gradually decreasing.On the contrary,that of the aspirin 300 mg/d group showed gradually increasing.Cross-sectional comparison of the three groups at different time points showed that there was no significant difference in the platelet inhibition rate among three groups before medication,7 days,6 months after medication (P ＞ 0.05).However,there was significant difference at 1 year after medication (P ＜ 0.05).The platelet inhibition rate inaspirin 300 mg/d group [(93.8 ± 18.6)％] was higher than that in aspirin 200 mg/d group [(83.7 ± 11.2)％]and aspirin 100 mg/d group [(76.6 ± 12.8)％] (P ＜ 0.05).During medication there were 9 patients of less than 50％ platelet inhibition rate in aspirin 100 mg/d group,5 patients in aspirin 200 mg/d group,3 patients in aspirin 300 mg/d group,and 2 patients of peptic ulcer bleeding in aspirin 300 mg/d group.Conclusions The appropriate dose of aspirin (100,200,300 mg/d) can play a very good anti-platelet effect.Increasing the dose on the basis of 100 mg/d,the platelet inhibition rate shows no increase in the short-term (≤6 months),but in the long-term (1 year) there may be differences.It may be associated with less aspirin resistance and the relative increasing bleeding risk.
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To analyze the clinical effects and safety of carotid endarterectomy [CEA] and carotid artery stenting [CA5] in the treatment of high-risk carotid stenosis patients. Total 63 patients who underwent CEA or CAS in our hospitals from January 2007 to December 2012 were selected in this study, and were randomly divided into an observation group and a control group. The patients in the observation group were subjected to CAS and those in the control group were subjected to CEA to compare the primary and secondary endpoints of the treatment. The arrival rates of the primary and secondary endpoints were 7.14% and 10.71% respectively in the observation group, while those were 11.43% and 11.43% respectively in the control group. There were no significant differences in the arrival rates of primary and secondary endpoints between the two groups [P > 0.05]. The efficacies and safety of CAS and CEA are similar in treating high-risk carotid stenosis patients
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@#Objective To observe the effect of low frequency electrical stimulation on dysphagia after stroke. Methods 60 patients with dysphagia after stroke were divided into treatment group and control group with 30 cases in each group. The control group was treated with swallowing exercise, while the treatment group was treated with low frequency electrical stimulation in addition. They were assessed with Fujishima's swallowing evaluation before and after treatment. Results The score increased after treatment in both groups (P<0.05), and increased more in the treatment group than in the control group (P<0.05). Conclusion Low frequency electrical stimulation can improve the effects of swallowing exercise on dysphagia after stroke.
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Object To establish a quantitative method for ephedrine and pseudoephedrine in the aqueous decoctions of MAHUANG TANG (ADMHT) by GC MS, and to determine the content of the two components in decoctions of the different recipes consisted of Herba Ephedrae, and other herbs by using the quantitative method will be established, so as to study the effect of compatible medicinal herbs on the release of the two components in Herba Ephedrae to decoctions Methods The quantitative method by the help of characteristic ion was used in GC MS Results The content of ephedrine and pseudoephedrine in decoction prepared from Herba Ephedrae and Semen Armeniacae Amarum evidently decreases, the content of two components in decoction prepared from Herba Ephedrae and Ramulus Cinnamomin evidently increases, the content of two components in decoction prepared from Herba Ephedrae and Radix Glycyrrhizae has no obvious change, as compared with that of two components in decoction from Herba Ephedrae alone Conclusion The method is good in the aspect of separable effect, sensitivity and reproducibility The method not only can quantify the two components, but also provide the bases of quality control for the pharmacokinetic study and therapeutic detection of Herba Ephedra recipes