Magnesium promotes vascularization and osseointegration in diabetic states / 国际口腔科学杂志·英文版

Diabetes has long been considered a risk factor in implant therapy and impaired wound healing in soft and hard oral tissues. Magnesium has been proved to promote bone healing under normal conditions. Here, we elucidate the mechanism by which Mg2+ promotes angiogenesis and osseointegration in diabetic status. We generated a diabetic mice model and demonstrated the alveolar bone healing was compromised, with significantly decreased angiogenesis. We then developed Mg-coating implants with hydrothermal synthesis. These implants successfully improved the vascularization and osseointegration in diabetic status. Mechanically, Mg2+ promoted the degradation of Kelch-like ECH-associated protein 1 (Keap1) and the nucleation of nuclear factor erythroid 2-related factor 2 (Nrf2) by up-regulating the expression of sestrin 2 (SESN2) in endothelial cells, thus reducing the elevated levels of oxidative stress in mitochondria and relieving endothelial cell dysfunction under hyperglycemia. Altogether, our data suggested that Mg2+ promoted angiogenesis and osseointegration in diabetic mice by regulating endothelial mitochondrial metabolism.

A novel double-ring aortic valve stent: its development and experimental study / 介入放射学杂志

Objective To discuss the feasibility and effectiveness of transcatheter implantation of double-ring aortic valve stent through puncturing the tip of the heart under thoracotomy.Methods A novel double-ring aortic valve stent was independently designed by the authors.Three healthy goats were selected for this study.A small incision on the left anterolateral thoracic wall was made to expose the cardiac apex,than the puncturing of the left ventricular apex was performed to establish the working pathway.Guided by fluoroscopy,along a hard guide wire a double-ring aortic valve stent was inserted through a 22-French sheath to the site above the aortic valve.By utilizing the opened outer ring of the stent,the double-ring aortic valve stent was accurately placed at the bottom of the aortic valve sinus.Then,the balloon was inflated and the stent was released to substitute the original aortic valve of the experimental goat.The experiment results were evaluated immediately after the procedure.Results Transcatheter aortic valve implantation (TAVI) was successfully accomplished in all the three experimental goats.DSA was performed immediately after the procedure and anatomy evaluation indicated that the position of the implanted artificial aortic valve was satisfactory,which could replace the work of original valve.Conclusion It is technically feasible and clinically effective to use this novel double-ring aortic valve stent to perform TAVI through transapical route by puncturing the left ventricular apex.

Construction and identification of Mcl-1 gene shRNA expression plasmid in targeted silenced macrophages / 西安交通大学学报(医学版)

Objective To study the expressions of myeloid cell leukemia-1 (Mcl-1 ) gene in mouse macrophages Raw264.7 and human macrophages THP-1,to screen out the cell lines with high levels of expression as the experimental cells,and based on the screening results to construct the short hairpin RNA(shRNA)eukaryotic expression plasmid targeting mice Mcl-1 gene for transfection and further screen out the shRNA expression plasmid with the most obvious effect in silencing Mcl-1 gene.Methods Semi-quantitative PCR method was used to detect the expression of Mcl-1 mRNA in the two kinds of macrophages.Western blotting was adopted to detect the expressions of Mcl-1 proteins in the two kinds of macrophages.Three different gene loci for Mcl-1 shRNA fragments were designed with small molecules interfering RNA (siRNA)software.Eukaryotic expression plasmid Mcl-1 shRNA 1-3 carrying the shRNA fragments was constructed by a company.And the eukaryotic expression plasmid vector was transfected into scavenger cells Raw264.7 mice via through the liposome.The transfection results 24 h and 48 h after transfection were observed under the inverted fluorescence microscope;Mcl-1 mRNA and protein expression were detected by real time quantitative PCR and Western blot,respectively.Results The relative expression levels of Mcl-1 mRNA and protein in mouse macrophages Raw264.7 were significantly higher than those of human macrophages (P <0.05).The shRNA expression vector constructed within 24 h and 48 h could decrease Mcl-1 mRNA and protein levels in Raw264.7 cells,especially with the most obvious silencing effect at 48 h.The 48-h transfection group differed significantly from normal group,liposome group and negative control group (P <0.05).Compared with Mcl-1shRNA1and Mcl-1shRNA2,Mcl-1shRNA3 had the strongest effect in silencing Mcl-1mRNA and protein.Conclusion We have successfully screened out experimental Raw264.7 cells and Mcl-1 shRNA eukaryotic expression plasmid which has an obvious silencing effect targeting on Mcl-1 in mice macrophages Raw264.7.

Specificity of screening of short hairpin RNA targeting Mcl-1 gene in Raw264.7 cells / 中国免疫学杂志

Objective:To transfect Mcl-1shRNA into Raw264.7 cells,and screen out specific shRNA eukaryotic expression plasmids with the most significant effect of silent Mcl-1 gene to figure out the effect of shRNA on Mcl-1 expression in murine macrophage cell line Raw 264.7.Methods: Specific shRNA was transfected into murine macrophage cell line Raw 264.7 via lipofectamine.Semi-quantitative RT-PCR and Western blot were respectively employed to test the changes in Mcl-1 mRNA level and Mcl-1 protein expressions 24 h and 48 h after the transfection ,and the silencing effects of the three pairs of specific shRNA fragments corresponding to different sites were analyzed.Results: Specific shRNA fragments at 24 h and 48 h could effectively reduce Mcl-1 mRNA and protein level ,with higher silencing effects than those of the normal group ,the lipofectamine group and the negative control group.There were statistically significant differences among them ( P<0.05 ).Among the three pairs of specific shRNA fragments corre-sponding to different sites ,Mcl-1 shRNA3 showed the most significant inhibiting effect on Mcl-1 mRNA and proteins.Conclusion:RNA interference can downregulate the level of Mcl-1 mRNA in murine macrophage cell line Raw 264.7 and greatly downregulate the expression of Mcl-1protein.Specific shRNA eukaryotic expression plasmids with the most significant effect of silent Mcl-1 gene have been screened out successfully.

Effect of Mcl-1 signaling pathway blockers on apoptosis of mouse macro-phages infected with Mycobacterium tuberculosis H37Rv / 中国病理生理杂志

[ ABSTRACT] AIM: To explore the effects of Mcl-1 signal pathway blockers on Mcl-1 expression, macrophage apoptosis and Mycobacterium tuberculosis in the model of mice infected with Mycobacterium tuberculosis H37Rv.METH-ODS:A mouse infection model was established by intraperitoneal injection of H37Rv suspension.The signaling pathway blockers AG490, PD98059 and LY294002 for JAK/STAT, MAPK and PI3K, respectively, were intraperitoneally injected into the mice infected with H37Rv.Cell acid-fast staining was used to observe whether the mouse peritoneal macrophages infected with H37Rv were successfully established.Immunocytochemical method was employed to detect Mcl-1 expression in the mouse peritoneal macrophages infected with H37Rv.The apoptotic rate in each group was measured by flow cytomer-ty.The scavenging capacity of apoptotic macrophages against H37Rv was determined by Mycobacterium tuberculosis colony counting.RESULTS:The result of cell acid-fast staining revealed the existence of dispersive arrangement of red short anti-acid Mycobacterium tuberculosis within infected macrophages.The result of cell immunocytochemistry showed strongly posi-tive expression of Mcl-1 protein in H37Rv infection group, AG490 treatment group and LY294002 treatment group, weakly positive expression of Mcl-1 protein in PD98059 treatment group, and negative expression of Mcl-1 protein in control group. The result of flow cytometry found that the macrophage apoptotic rate in H37Rv infection group was higher than that in con-trol group, while that in PD98059 treatment group was high than that in other groups with statistically significant differences (P<0.05).The result of Mycobacterium tuberculosis colony counting showed that PD98059 treatment had the most signifi-cant inhibitory effect on H37Rv strain.CONCLUSION: Mcl-1 signaling pathway blockers increase the apoptotic rate of macrophages infected with Mycobacterium tuberculosis H37Rv and inhibit the growth of Mycobacterium tuberculosis by inhibi-ting the signaling pathways of JAK/STAT, MAPK and PI3K, among which the MAPK has the most obvious interfering effect on Mcl-1, and leads to the highest apoptotic rate of infected macrophages and the strongest bacteriostasis.

Effects of Mcl-1 silencing on apoptosis of mouse peritoneal macrophages infected with different virulence of Mycobacterium tuberculosis / 中国病理生理杂志

AIM:To investigate the effect of inhibiting Mcl-1 gene expression on apoptosis of mouse peritoneal macrophages infected with different virulence of Mycobacterium tuberculosis using a technique of RNA interference .METH-ODS:The BALB/c mice were infected with prepared bacterium of the virulence strains of Xinjiang , H37Rv, H37Ra and BCG.Mcl-1-shRNA was applied to the mouse model of infection , and the control groups were set up .On 1 d, 3 d, 5 d and 7 d, the mouse peritoneal macrophages were collected .The expression of Mcl-1 at mRNA and protein levels was deter-mined by real-time PCR and Western blot .The apoptotic rate of peritoneal macrophages was analyzed by flow cytometry . RESULTS:The expression of Mcl-1 at mRNA and protein levels was up-regulated in the peritoneal macrophages from the mice infected with different virulence of Mycobacterium tuberculosis, and the cells from the mice infected with virulence strains of Xinjiang and H37Rv expressed higher level of Mcl-1 than the uninfected control cells (P<0.05).The expres-sion of Mcl-1 at mRNA and protein levels was reduced by RNA interference as compared with control group ( P<0.05 ) . Inhibition of Mcl-1 expression induced apoptosis of peritoneal macrophages in the mice .CONCLUSION: The Mcl-1 ex-pression at mRNA and protein levels in mouse peritoneal macrophages infected with different virulence of Mycobacterium tu-berculosis was effectively suppressed by Mcl-1-shRNA, which can induce macrophage apoptosis .

Sequential immune’s effects of traditional BCG primary immunization and IL-12 combined with Ag85A DNA booster immunization in mice / 中国人兽共患病学报

The aim of this study is to investigate the immune effects of BCG primary immunization and IL-12 combined with Mycobacterium tuberculosis Ag85A DNA vaccine booster immunization on mice .We randomly divided the mice into 7 groups ,namely PBS negative controls ,BCG controls ,pcAg85A controls ,BCG primary immunization combined with Ag85A booster immunization controls ,BCG primary immunization combined with Ag85A and IL-12 booster immunization controls , BCG primary immunization combined with IL-12 booster immunization controls ,and BCG primary immunization combined with pcDNA3 .1 booster immunization controls .Implementing the immune in procedure of BCG primary immunization and cytokine IL-12 booster immunization combined with mycobacterium tuberculosis Ag85A DNA ,we observed the immune effect on mice by detecting the mice serum total IgG , specific lymphocyte proliferation and cytokine levels in 4 ,6 ,8 weeks after the last immunization .Comparing the mice immunized in the strategy of BCG primary immunization and cytokine IL-12 combined with Mycobacterium tuberculosis Ag85A DNA vaccine strengthening immunization to the mice in other groups by other immune ways ,we found that ,in BCG/Ag85A+ IL-12 groups ,IgG in-creased significantly (P＜ 0 .05) ,specific lymphocyte prolifera-ted significantly ,and after strengthening immunization IFN-γlevels ,IL-2 levels and IL-4 levels in the three periods were 128 .2 ±20.4,190.2±16.51,244.2±39.14 ;146.2±17.29,271.6±16.36and16.36±28.12 ;68.6±6.62,96.6±5.5and5.5± 10 .71 ,respectively ,which were higher than those in other groups (P＜0 .05) .It’s suggested that the immunization way of BCG primary immunization and cytokine IL-12 combined with Mycobacterium tuberculosis Ag85A DNA vaccine booster immu-nization could significantly enhance the humoral and cellular immunity of the bodies ,and provide the basis for further study on protective effect test in animals .

Transcatheter establishment of an animal model with acute aortic valve regurgitation：an experimental study / 介入放射学杂志

Objective To explore the feasibility and effectiveness of interventional transcatheter destruction of the aortic valve to establish an animal model with acute aortic valve regurgitation. Methods Eight healthy goats were used for this study. A limited sternotomy approach was used to access the apex of the heart. Puncturing of the apex of the heart was performed to establish a wire track, then, under fluoroscopic guidance a 10 F sheath was inserted along this track of hard wire until to the ascending aorta above the aortic valve. The internal sheath was removed. Via the 10 F sheath a 10 mm occluder of ventricular septal defect (VSD) was introduced into the ascending aorta above the aortic valve. The sheath was pulled back to the left ventricle, while the occluder remained in the ascending aorta above the aortic valve. Then the occluder was quickly pulled back into the left ventricle in order to make some certain damage to the aortic valve. And an acute aortic valve regurgitation model was thus established. Angiography of ascending aorta above the aortic Among the 8 animals, two died of acute left ventricular failure on the spot due to excessive regurgitation blood flow after the operation. Macroscopically, damage of the aortic valve was seen. In the six survivors, angiography of ascending aorta above the aortic valve and Doppler echocardiography showed that moderate degree of regurgitation was detected in 5 and small amount of regurgitation in one. Two experimental goats with moderate degree of regurgitation died of heart failure separately at seven days and fifteen days after the operation. The remaining four experimental goats survived for more than three months. Follow- up checkups with echocardiography suggested the presence of mild- moderate degree of regurgitation. Conclusion Acute aortic valve regurgitation model in experimental goats can be established through transapical transcatheter damage of aortic valve by quickly pulling back a VSD occluder which has been placed in the ascending aorta above the aortic valve. This method is clinically feasible, technically simple and repeatable, the result is reliable, and the degree of regurgitation is controllable.

Three-dimensional finite element analysis of canine distalization through reducing resistance and distraction osteogenesis / 中国组织工程研究

BACKGROUND:Peridental membrane distraction osteogenesis exerts the functions at peridental membrane and leads to tooth movement. Alveolar bone distraction osteogenesis produces tooth movement through the displacement of the whole bone plate. OBJECTIVE:To establish three-dimensional finite element model of upper and lower jaw of healthy adults under three different conditions, and to compare the stress distribution and distal movement of the models using three-dimensional finite element analysis method. METHODS:Model 1:three-dimensional finite element model of the canine under normal conditions using a variety of software;Model 2:three-dimensional finite element model of the canine after distracting osteggenesis of the periodontal ligament;Model 3, three-dimensional finite element model of the canine after reducing resistance and distracting osteggenesis of the alveolar bone. The force loadings were stimulated among these models. RESULTS AND CONCLUSION:The biggest displacements on those three models occurred in canine crown on 1/3, and the displacement quantity on canine was model 2>model 3>model 1. The biggest equivalent stress concentrated in distal alveolar crest, and the equivalent stress was model 2

Experimental study of transcatheter aortic valve implantation assisted with snare to fix the delivery system / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility and effectiveness of transcatheter aortic valve implantation assisted with snare to fix the delivery system.</p><p><b>METHODS</b>This study was made in 5 healthy goats. After the abdomen was opened and the abdominal aorta was exposed, a stiff guide wire was advanced into the apex of the left ventricle through abdominal arterial puncture points. The delivery catheter equipped with valved stent was inserted into the descending aorta under fluoroscopy along the stiff guide wire. A minimal thoracic surgery approach was used to access the apex of the heart. A J-type guidewire and 5 F multifunction catheter were placed transapically and across the aortic valve down to the descending aorta. The snare was introduced through the 5 F catheter into the ascending aorta and was controlled to seize the head of stent delivery catheter. Then the delivery catheter was advanced into the left ventricle. The valved stent was positioned in the desired position under aortography and then the balloon was dilated and the valved stent was deployed into the aortic annulus assisted with snare to fix the catheter to prevent stent dispositions. Aortic angiography and echocardiography were performed to evaluate of valve performance post procedure.</p><p><b>RESULTS</b>The interventional procedure was completed successfully in all 5 goats. The mean aortic annulus diameter was (23.8 ± 2.6) mm, two valved stent of 23 mm diameter and three valved stent of 26 mm in diameter were implanted. The operation duration and X-ray exposure time were (112.3 ± 19.5) min and (16.8 ± 5.2) min, respectively. Immediate observation after procedure showed that the valved stents were in the desired position after implantation by angiography and echocardiography. No moderate to severe aortic regurgitation was observed. All goats were alive at 1 month post procedure.</p><p><b>CONCLUSIONS</b>The procedure of transcatheter implantation of a balloon-expandable valved stent into the aortic valve position of goats assisted with snare to fix the delivery catheter is feasible and effective. This procedure might be suitable also for patients with noncalcified aortic stenosis.</p>