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Objective:To explore the application value of four-dimensional automatic left ventricular quantitation(4D Auto LVQ) technology, in evaluating the myocardial mechanics in patients with different risk stratifications of hypertrophic cardiomyopathy(HCM).Methods:A total of 88 HCM patients and 20 healthy volunteers were selected from February 2020 to February 2022 in the First Affiliated Hospital of Zhengzhou University. According to the HCM Risk-SCD score, HCM patients were divided into 3 groups: low-risk group( n=49), intermediate-risk group( n=21), and high-risk group( n=18). Conventional ultrasound parameters were collected, and 4D Auto LVQ technology was used to obtain the mechanical parameters of left ventricular myocardium, including global longitudinal strain(GLS) , global circumferential strain(GCS), global area strain(GAS), global radial strain(GRS), twist and torsion. The differences in these parameters among the four groups were compared. The predictive values of conventional ultrasound parameters and myocardial mechanical parameters in patients with intermediate- and high-risk HCM patients were analyzed by ROC curve. Results:①Left ventricular end-diastolic diameter, left ventricular end-diastolic volume, left ventricular end-systolic volume, and peak systolic velocity of mitral annulus in the low-, intermediate-, and high-risk groups were lower than those in the control group while left ventricular maximal wall thickness(LVMWT) and early diastolic peak velocity of mitral value orifice/early diastolic peak velocity of mitral annulus(E/e′) were higher, left atrial diameter(LAD) and left ventricular outflow tract gradients(LVOTG) in the intermediate- and high-risk groups were higher than the low-risk group(all P<0.05). ②Compared with the control group, the GLS of HCM patients was lower, and the GLS of the intermediate- and high-risk groups was lower than the low-risk group. GCS and GRS in the intermediate- and high-risk groups were lower than those in the low-risk group. GAS in the high-risk group was lower than the low-risk and the control group, but higher than the intermediate-risk group(all P<0.05). Compared with the control group, the twist and torsion in the intermediate- and high-risk groups were higher, but lower than the low-risk group, and the differences were statistically significant(all P<0.05). ③The ROC results showed that the area under the curve(AUC) of the model containing conventional ultrasound parameters(LVWMT, LAD, and LVOTG) for predicting intermediate- and high-risk HCM patients was 0.811, with a sensitivity of 0.769 and a specificity of 0.755. The AUC of the conventional ultrasound parameters combined with myocardial mechanical parameters was 0.904, as the sensitivity was 0.667 and the specificity was 0.980. Conclusions:4D Auto LVQ can evaluate the mechanical characteristics of LV myocardium in HCM patients with different risk stratifications. Myocardial mechanical parameters combined with conventional ultrasound parameters can improve the diagnostic performance of patients with intermediate- and high-risk HCM.
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Objective Bone marrow mesenchymal stem cells (BMSCs) were induced to differentiate to the special histological types of neurons in vitro.The morphological change of cells and positive expression of specific antigen on membrane were studied,and the function of connection between the induced BMSCs was also detected.The feasibility of BMSCs differentiate to the special histological types of neurons was investigated.Methods BMSCs were divided into group Ⅰ (induced with bFGF+GDNF),group Ⅱ (induced with bFGF+GDNF+WHI-P131 +Shh),and control group (no revulsive).The morphologic change of cells was observed,and the positive rate of neuron specific surface antigen and the content of dopamine were detected.Formation of mature synaptic structure was detected by immunohistochemical assay of postsynaptic density protein 95 (PSD-95) expression,and synaptic loop was shown by FM1-43 stain synaptic vesicles.Results By immunohistochemical staining,the positive rates of dopamine transporter (DAT) and tyrosine hydroxylase (TH) in group Ⅱ were significantly higher than those in group Ⅰ,and dopamine can been detected in cell culture supematant of group Ⅱ.After BMSCs was induced into dopamine neuron-like cells,number and length of cell protrusions,positive rate of PSD-95 and fluorescence intensity of FM1-43 in group Ⅱ were significantly higher than those of group Ⅰ.Conclusions There were no significant change in positive rate of neuron-specific surface markers,rate of cell survival and differentiation rate after BMSCs differentiated to dopaminergic neuron-like cells.The number and length of cell protrusions,content of dopamine in cell culture supematant,positive rate of dopaminergic neuron-specific surface antigen (DAT and TH),synaptic function index (positive rate of PSD-95 and fluorescence intensity of synaptic loop) of group Ⅱ were all significantly higher than that of group Ⅰ.
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Objective To investigate the value of three-dimensional speckle tracking imaging(3D-STI) in assessment of left ventricular regional systolic function in acute myocardial infarction model of dogs.Methods Left anterior descending (LAD) coronary artery was ligated in 24 adult beagle dogs.Longitudinal strain(LS) of every left ventricular segment before ligation and 180 min after ligation,and the time for acquisition and analysis were obtained using two-dimensional speckle tracking imaging (2D-STI) and 3D-STI.After the experiment,left ventricular myocardium were determined by TTC staining and divided into two groups:infarcted myocardial segments and non-infarcted myocardial segments.Results Experimental model of acute myocardial infarction was established successfully in 20 dogs.After ligation,both LS of 2D-STI and 3D-STI in infarcted myocardial segments were significantly lower (P ＜ 0.01).The time for acquisition and analysis of the images by 3D-STI were significantly shorter than that by 2D-STI (P ＜0.01).The area under the ROC curve of 3D-STI was larger than that of 2D-STI.A cut-off value of-12.56％ for LS of the 3D-STI had 77.9％ sensitivity and 88.2％ specificity in predicting acute myocardial infarction.Conclusions 3D-STI is a convenient,accurate method for evaluating left ventricular regional systolic function.
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ObjectiveTo investigate a new way to prevent hyperacute rejection (HAR) during liver xenotransplantation through blocking the xenograft with recipient blood serum before transplantation.MethodsTwenty guinea-pig (GP) and Sprague-Dawley (SD) rats were pair-matched as donor and recipient randomly.Before transplantation,blood serum collected from other SD rats was inactivated at 45 ℃ in water bath for 30 minutes.Guinea-pig donor livers from experimental group ( n =10 ) were pre-perfused by 0.1％ solution of this blood serum,and donor livers from control group (n =10) were treated by Ringer solution.Then orthotopic liver xenotransplantations were performed by the modified two-cuff technique immediately.Liver morphology changes and survival rate and time of recipients were observed,and histopathological lesions were detected by HE staining,and liver ALT level was evaluated.ResultsThe operation time and anhepatic phases between two groups were not different significantly ( P ＞ 0.05 ).The survival rate of recipients from experimental group was higher,and its survival time was longer than that of control group significantly (P ＜ 0.01 ).The liver histological changes such as thrombosis and interstitial bleeding in experimental group was less severe than that in control group (P ＜0.01 ).The level of ALT in blood serum of rats from experimental group were lower than that from control group significantly ( P ＜ 0.05).ConclusionsThe results suggested that blocking the donor graft with recipient blood serum inhibits HAR during liver xenotransplantation.
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Present research of bone marrow mesenchymal stem cells (BMSCs) mainly contains the studies of the characteristics of biology, the induced differentiation, the mechanism of regulation and so on. The research of the characteristics of biology and the osteogenic and adopocitic induction are comparatively mature, showing many biological characteristics such as adherence, plasticity, heterology, self-renewal, rapid clone formation and transplantation. Adherence combined with density gradient centrifugation method is widely used in the isolation and purification of BMSCs. As to neural induction, there are many uncertainties, such as morphous of typical neurons, specific labeling, excitability, synaptic connection with other neurons, synaptic potential, and whether the induction of fully functional neurons from BMSCs is possible. In addition, the research of the regulation mechanism is mostly uncertain, and there are still many safety problems.