الملخص
ObjectiveTo clarify the value of the left ventricular longitudinal strain（LVLS）parameters in patients with cardiac amyloidosis （CA） and primary hypertension with left ventricular hypertrophy （HLVH）. MethodsForty-one patients confirmed with CA were selected and assigned to CA with hypertension group （n =14） and pure CA group （n=27） based on the initial diagnosis with or without hypertension. Twenty patients with primary hypertension-induced left ventricular hypertrophy （HLVH group） and twenty healthy controls were also selected， matching for gender， age， and body surface area. Clinical data， conventional echocardiography parameters were collected and LVLS parameters were measured. Within-group variations were compared among the four groups， and pairwise comparisons were conducted between groups. The sensitivity and specificity of each parameter in predicting CA were judged by the receiver operator characteristic （ROC） curvy in CA and HLVH patients with left ventricular ejection fraction （LVEF） preserved. ResultsAmong the conventional echocardiography parameters， LVEF and left ventricular end-diastolic diameter （LVEDD） were lower in the CA with hypertension group and pure CA group compared with the higher values in the HLVH group and control group. Whereas， left ventricular posterior wall thickness （LVPWT）， relative wall thickness （RWT）， and average E/e' were higher in the two CA groups compared with the HLVH group （all P＜0.05）.Among the LVLS parameters， Global longitudinal strain （GLS） was the worst in the CA with hypertension group so as pure CA group， modest in the HLVH group， and highest in the control group. On the contrary， relative longitudinal strain and ejection fraction strain ratio （EFSR） were the highest in the CA with hypertension group so as to pure CA group， modest in the HLVH group， and lowest in the control group （all P＜0.05）. ROC analysis showed that when LVEF was preserved， the absolute value of GLS less than 14.35% and EFSR higher than 4.28 could effectively distinguish CA from HLVH （all AUCs＞0.9，all P＜0.05）； meanwhile GLS showed high sensitivity（100%） and EFSR showed great specificity（95%）. There were not statistically significance in any parameter between CA with hypertension group and pure CA group（all P＞0.05）. ConclusionWhether CA was complicated with hypertension or not， there were statistically significance among routine echocardiography and LVLS parameters compared with HLVH. In particular， GLS and EFSR are accurate in predicting CA in patients with myocardial hypertrophy and preserved LVEF.
الملخص
BACKGROUND:Our previous work demonstrated that bone marrow mesenchymal stem cells (BMSCs) transplantation could improve cardiac function in rats with myocardial infarction.However,the overall efficacy was unsatisfactory,and there was a low efficiency of BMSCs differentiating into cardiomyocytes in the local infarct myocardium.OBJECTIVE:To transfect long non-coding RNA-Braveheart (IncRNA-Bvht) into BMSCs in order to observe whether it could promote cardiomyocyte differentiation of BMSCs in vitro.METHODS:pLVX-IRES-ZsGreen1-IncRNA-Bvht vector was constructed and applied to transfect IncRNA-Bvht into bMSCs,and then,the transfection efficiency was detected.BMSCs were obtained from C57BL/6 mice and cultured ir vitro.Passage 3 cells were divided into three groups:BMSCs group,null vector group and IncRNA-Bvht group.All cells in the three groups were cultured in the normal condition for 48 hours and cardiomyocytes differentiation was induced by 5-azacytidine for another 24 hours followed by 2-week culture under normal conditions.Cardiomyocyte differentiation of BMSCs was observed under fluorescence microscopy and expression of cardiac specific cell markers including troponin T and myosin were examined using immunofluorescent staining,western blot assay,and qRT-PCR.RESULTS AND CONCLUSION:Cell morphological changes could be observed in all the groups 2 weeks after the induction.Interconnected cells arranged consistently in all the three groups.Immunofiuorescent staining results showed that the expression of troponin T and myosin was notably positive,and the proportion of troponin T positive cells was significantly increased.qRT-PCR and western blot assay results indicated that there were significantly increased levels of troponin T and myosin in the IncRNA-Bvht group as compared with the BMSCs and null vector groups (P ＜ 0.01),suggesting that IncRNA-Bvht could efficiently promote cardiomyocyte differentiation of BMSCs in vitro.