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Objective To explore the effect of expression of protein kinase C receptor 1(RACK1) induced by lipopolysaccharide (LPS) on Sonic hedgehog(SHH) signaling pathway in rat puhnonary microvascular endothelial cells (RPMVEC).Methods The healthy male SPF grade SD rat with 100-120 g body weight were gotten from the laboratory animal center of Anhui province.Using immunocytochemistry method,the expression of RACK1 protein in RPMVECs was detected,cultured RPMVECs were randomly divided into different groups as LPS dose-dependent group,SAG(smoothened Agonist,a SHH signaling pathway specific agonist) dose-dependent group,LPS time-dependent group,SAG time-dependent group and LPS+SAG group.In LPS dose-dependent groups,RPMVECs were cultured with 0.1,1,10 mg/L LPS for 8 h.In LPS time-dependent groups,RPMVECs were cultured with 10 mg/L LPS for 0,2,4,8,12,24 h.In SAG dose-dependent groups,RPMVECs were cultured with 0.1,1,10 μ mol/L for 8 h.In SAG time-dependent groups,RPMVECs were cultured with 1 μ mol/L SAG for 0,2,4,8,12,24 h.In LPS+SAG group,RPMVECs were cultured with 1 μ mol/L SAG 8 h after 10 mg/L LPS treatment for 1 h.In addition,blank group,LPS group and SAG group were set for control.Western blot were used to detect the level of RACK1 and RT-PCR were used to detect the expression of GLI-1 mRNA after intervention.Results Immunocytochemistry revealed that RACK1 were present in RPMVEC.1.In LPS dose-dependent groups (0,0.1,1,10 mg/L),the level of RACK1 elevated as LPS dose increased correspondingly with inter-group difference (P＜0.05);the relative expression levels of GLI-1 mRNA were (1.109 + 0.063),(1.039 + 0.135),(0.813 ± 0.066),(0.770 + 0.105),(1 mg/L vs.10 mg/L,P＞0.05;the rest P＜0.05).In LPS time-dependent groups,the relative expression level of RACK1 at 2 h (0.370 + 0.010) was higher than that at 0 h (0.329 ± 0.008),peaked at 12 h (1.296 ± 0.048),and compared with 0 h,there was significant differences (F=1 272.204,P＜0.05).The relative expression level of GLI-1 mRNA was decreased at 2 h (0.929 ±-0.007),and compared with 0 h(1.089 ± 0.042),there was significant differences (F=306.609,P＜0.05).2.In SAG dose-dependent groups,there was no significant difference in level of RACK1 between groups(all P＞0.05).The relative expression levels ofGLI-1 mRNA were (1.109 ± 0.063),(1.169 ± 0.052),(3.468 ± 0.128),(3.434 ± 0.054),(0 μ mol/L vs.0.1 μ mol/L and 1 μ mol/L vs.10 μ mol/L,P＞0.05,the rest P＜0.05).Among SAG time-dependent groups,there was no significant difference in levels of RACK1 protein(P＞0.05).The relative expression level of GLI-1 mRNA increased at 2 h (3.027 ± 0.065),and compared with 0 h (2.651 + 0.123),there was significant differences (F=132.841,P＜0.05).3.In LPS+SAG intervention groups,the expression of RACKI was lower than that in LPS group (0.831 ±0.040 vs.1.189 ± 0.149,P＜0.05),and the expression of GLI-1 mRNA was higher than that in LPS group (2.720 + 0.130 vs.0.796-4-0.082,P＜0.05).Conclusions The LPS up-regulates the expression of RACK1 in RPMVECs,and the activated SHH signaling pathway can down-regulate the expression of RACK1 induced by LPS in RPMVECs.
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Objective To prepare the multi-functional ultrasound contrast agents,which were investigated for ultrasound(US)/MR dual-mode imaging and high-intensity focused ultrasound(HIFU)synergism in vitro.Methods Double emulsion method was used to prepare the superparamagnetic iron oxide(SPIO)-loaded PLGA microcapsules(s-PLGA),and its morphology,size,Fe3O4 loading capacity were assessed.Then,the prepared s-PLGA microcapsules with different concentrations were applied to perform ultrasound and MR imaging in vitro.In addition,the degassed bovine liver in vitro was directly injected into 200 μl s-PLGA in saline(0.5 mg Fe/ml)just before HIFU ablation,the saline(200 μl)and pure PLGA (200 μl)were employed for control.After HIFU ablation,the volume of coagulated tissue irradiated by HIFU was calculated.Results The s-PLGA microcapsules were observed with regular spherical morphology and its average size was(885.6 ± 133.2)nm.In vitro,the s-PLGA showed hyperechogenicity in US imaging and MR negatively enhanced effeet in T2WI,the volume of coagulated tissue irradiated by HIFU after local injection of s-PLGA was larger than that of saline and pure PLGA(P＜0.05).Conclusions The prepared s-PLGA microcapsules are successfully acted as dual-mode biological imaging contrast agents for ultrasound and MR imaging and HIFU synergism in vitro.
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Objective To prepare polyclactic-co-glycolic acid(PLGA) polymer ultrasound contrast agent loading sudan black dye (SB-PLGA) and study the enhancement effect of it on rabbit lymph nodes imaging and as a sentinel lymph node (SLN) biopsy in the feasibility and value of the indicator.Methods SB-PLGA ultrasound contrast agent was made by double emulsion and freeze-drying methods.Thigh subcutaneous rabbit VX2 tumor model of eight lymph nodes were set up with the foot pad subcutaneous injection of contrast agents to get contrast-enhanced ultrasound imaging of the popliteal lymph node and the second inguinal lymph node stations.Then the blue stained lymph nodes were resected by popliteal lymph node dissection and the second station lymph nodes were also observed after 30 mins respectively,lymph nodes were examined by frozen sections HE staining in parallel.Results SB-PLGA microbubbles had a tight size distribution.Ultrasound imaging can be significantly enhanced lymph node imaging,the second station lymph node imaging was not obvious.Popliteal lymph node dissection for lymph node staining,30minutes later,frozen sections HE staining were seen within the lymph node contrast agent present in the lymphatic sinus and a large entry of macrophages.Inguinal lymph node dissection showed the second station of lymph nodes no blue staining.Conclusions SB-PLGA ultrasound contrast agent is good for sentinel lymph node imaging and biopsy indicator.Contrast agent retention and accumulation in the lymph nodes by the uptake of macrophages may be associated with the mechanisms of lymph node enhanced imaging.
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Objective To prepare a kind of superparamagnetic iron oxide (SPIO) and doxorubicin loaded multifunctional polymer microbubbles (MPMBs),and to explore its potential application as an ultrasound(US)/magnetic resonance (MR) imaging contrast agent in vitro.Methods The MPMBs and normal polymer microbubbles (PMBs) were made by double emulsion and freeze-drying methods.The physical property,drug encapsulation efficiency and the drug-loading efficiency of MPMBs were determined,and the release property and US/MR imaging enhancement of MPMBs were observed.Results The MPMBs had a regular shape and narrow size distribution.The drug encapsulation efficiency was (60.20±2.69) ％,and the drug-loading efficiency was (6.02 ± 0.27) ％.The in vitro release experiment showed that ultrasound can promote the release of doxorubicin in MPMBs.US imaging in vitro showed that the enhancement of MPMBs was better than PMBs,and MR imaging in vitro conformed that MPMBs could well enhance MR imaging.Conclusions The MPMBs is a multifunctional contrast agent with the treatment function as well as US/MR dual-mode imaging enhancement effect.