Ultrasound speckle tracking imaging in evaluation on left ventricular function in acute stage chest blast injury of rabbits / 中国医学影像技术

Objective To evaluate the impact of chest blast injury on left ventricular function and myocardial strain with speckle tracking imaging (STI).Methods Fifty healthy New Zealand rabbits were randomly divided into 4 groups.Five rabbits without blast injury were used as a normal group,and the other rabbits were placed in specific semi-enclosed blasting environment in accordance with the different distance of the explosion.With instantaneous detonators,slight,medium and heavy chest blast injury animal models were produced and labeled as A,B,and C group (each n=15),respectively.The left ventricular function was measured with conventional echocardiography and STI.The longitudinal strain (LS) of the left ventricle was measured with two-dimensional strain analysis software and statistically analyzed.Results There was no significant difference of ejection fraction (EF) and fractional shortening (FS) in the left ventricle after chest blast injury between group A and normal group (all P＞0.05),while LS of anterior wall,anterior septum wall and lateral wall of group A significantly decreased compared with those of normal group (all P＜0.05).In group B and C,the left ventricular EF,FS and LS of each segment were lower than those of normal group (all P＜0.05).In group C,the left ventricular EF,FS and LS of each segment were lower than those in group A (all P＜0.05).There was no significant difference of EF and FS between group B and group C.In group C,LS of anterior wall and lateral wall of basal segment and middle segment were lower than those of group B (all P＜0.05).Conclusion STI can reflect functional changes of left ventricle in each segment earlier and more sensitively after chest blast injury.

Role of homocysteine to promote the vascular smooth muscle cell proliferation by MiR-125 b methylation / 中国药理学通报

Aim To investigate the role of miR-125 b and its DNA methylation in homocysteine ( Hcy )-in-duced vascular smooth muscle cells( VSMCs) prolifera-tion. Methods VSMCs were stimulated with 0,50, 100, 200, 500 μmol · L-1 Hcy respectively. Then qRT-PCR was used to detect the mRNA levels of miR-125b,and nested-touchdown methylation-specific PCR ( ntMS-PCR) was used to detect the methylation levels of miR-125b. VSMCs were transfected with miR-125b precursor or the inhibitor of miR-125b ,then 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyl tetrazolium bromide ( MTT ) assay was used to reflect the proliferation of VSMCs. The distribution of CpG islands of miR-125b promoter region was analyzed by bioinformatics meth-ods. VSMCs were stimulated with 100 μmol·L-1 Hcy and transfected with or without DNA methylation inhib-itors 5-nitrogen impurity cytidine ( AZC) , then the ex-pression of miR-125b was detected by qRT-PCR. Re-sults The mRNA levels of miR-125 b were decreased in 100,200,500 μmol·L-1 Hcy group compared with 0 μmol·L-1 Hcy group. The precursor of miR-125b could inhibit the proliferation activity and the inhibitor of miR-125 b could increase the proliferation activity of VSMCs cells. Bioinformatics analysis indicated that MiR-125 b promoter region had a CpG island whose length was 792 bp ( 1881-2672 ) . The miR-125 b pro-moter region methylation levels increased after Hcy in-tervention ( P <0. 01 ) . The expression level of miR-125 b increased after AZC intervention ( P <0. 05 ) . Conclusions ① Hcy promotes vascular smooth mus-cle cell proliferation maybe by down-regulating the ex-pression of miR-125b. ② Hcy down-regulates the ex-pression of miR-125 maybe by up-regulating the methy-lation levels of miR-125b promoter region.

Initial observation of blast injury of liver by real-time shear wave elastography / 中华超声影像学杂志

Objective To explore the application value of real-time shear wave elastography(SWE) in the liver injury caused by the blast injury.Methods The abdominal mild,moderate and severe blast injury animal models were built,liver and abdominal cavity conventional ultrasound scan and liver SWE measurement were processed before and immediately post-blast,and then the two groups' liver alanine aminotransferase (ALT) and the liver pathology results were compaired.Results The conventional ultrasound scan,immediately after the injury,had found no abnormities of the hepatic tissue in the mild blast injury group,while varying degrees of liver capsular rupture,part of the liver parenchyma regional uneven echo,subcapsular hematoma,obvious liver parenchyma interruption,effusion between the disruption of liver parenchyma and abdominal cavity effusion etc.a series of liver injury had been found in the moderate and severe groups,and the severe blast injury group was more obvious.Three groups' immediately liver elasticity and ALT of post-blast liver injury were increased compared with the pre-blast,the liver elasticity and ALT of each group pre-and post-blast comparing had statistically signifcant (P ＜0.05),and the three groups post-blast immediately liver elasticity and ALT and any two groups' comparing also had statistically significant (P ＜0.05).Conclusions After the blast injury,the changes of liver elasticity were associated with the liver injury degree,the higher elasticity values suggest the heavier damage.Based on conventional ultrasonography,SWE could provide a new evaluation method for the judgement of liver balst injury,especially in the diagnosis of mild liver blast injury.

Role of ERO1αand its DNA methylation in homocysteine-induced inhibition of hepatocyte proliferation / 中国药理学通报

Aim To explore the role of ERO1 αand its DNA methylation in homocysteine (Hcy)-induced in-hibition of hepatocytes proliferation.Methods The hepatocytes stimulated with 0 μmol·L -1 Hcy were set as the normal group (NC group)and the hepatocytes stimulated with 1 00 μmol·L -1 Hcy as the experimen-tal group (Hcy group).Methyl thiazolyl tetrazolium (MTT)reduction assay was used to reflect the prolifer-ation of the hepatocytes;qRT-PCR and Western blot were used to detect the mRNA and protein levels of ERO1 α;the expression of green fluorescence protein was observed in hepatocytes after the recombinant plas-mid of ERO1 α was constructed,which was used to confirm if the recombinant plasmid into hepatocytes was successful,then the mRNA and protein levels of ERO1 αwere assayed and the proliferation of the hepa-tocytes was also detected;ntMSP was used to detect the change of ERO1 αDNA methylation.Results The mRNA and protein levels of ERO1 αwere decreased in Hcy group compared with NC group,and the prolifera-tion activity of hepatocytes in Hcy group was de-creased.Sequencing result showed that the recombi-nant plasmid of ERO1 αwas constructed successfully. QRT-PCR and Western blot revealed that ERO1 αwas overexpressed. The result of MTT suggested that ERO1 αoverexpression restored hepatocyte proliferation inhibited by Hcy.Hcy caused ERO1 αDNA hyperm-ethylation.Conclusions Hcy inhibits hepatocyte pro-liferation by downregulating the expression of ERO1 α, and methylation of ERO1 αpromoter may play a role in this process.

The levels of NO decrease induced apoptosis in human placental trophoblast cells through oxidative stress / 中国药理学通报

Aim To investigate the possible mecha-nisms of the levels of NO decrease induced apoptosis in human placental trophoblast cells. Methods Human placental trophoblast cells ( HTR-8 ) were cultured in 5 ml DMEM-F12 culture medium with 37℃ 5% CO2 . Then, the old culture medium was discarded and re-placed with 10,100,500,1 000 μmol·L-1 L-NAME, and the group without L-NAME was set as the control group, cultured for 48h. The effects of L-NAME on the survival of cells were detected by methylthiazolyldiphe-nyl tetrazolium bromide ( MTT); the content of NO in cells was tested by nitrate reductive enzymatic;trans-mission electron microscopy, flow cytometry analysis and Annexin-V FITC dyeing were used to test the effects of L-NAME on apoptosis in HTR-8 cells;restore Fe3+ colorimetric assay was applied for detection of to-tal antioxidant capacity ( T-AOC ) , xanthine oxidase for detection of superoxide dismutase ( SOD) activity, and thiobarbituric acid colorimetry for determination of content of MDA. Results Compared with the control group, the survival rate of HTR-8 cells and the levels of NO in 100,500,1 000 μmol·L-1 L-NAME group were significantly reduced(P<0.05,P<0.01). Flow analysis and Annexin-V FITC staining showed that L-NAME could induce cell apoptosis in a dose-dependent manner. The number of cell apoptosis was negatively correlated with the content of NO ( r = -0.5210 ) in HTR-8 cells. Transmission electron microscopy results showed that compared with the control group, the ex-perimental group's cell nucleus shape was irregular, nuclear pyknosis in irregular shape, the chromatin ag-glutination or side the collection, mitochondrial swell-ing or enrichment, crest fracture or dissolved, even vanished, forming the vacuole, especially in 100 μmol ·L-1 L-NAME group, the apoptotic bodies obviously appeared. At the same time, T-AOC, SOD levels in HTR-8 cells decreased ( P <0.05 ) , and the MDA content increased ( P<0.05 ) . The number of cell ap-optosis was negatively correlated with the level of T-AOC ( r= -0.3212 ) , SOD ( r= -0.2779 ) in HTR-8 cells , while positively correlated with the content of MDA(r=0.2807). Conclusion Oxidative stress may play an important role in the levels of NO decrease in-duced apoptosis in human placental trophoblast cells.