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Objective:To prepare urokinase targeted thrombus microbubbles combined with low frequency ultrasound to dissolve thrombus in rabbit femoral artery, and to explore the mechanism of thrombolysis through the change of urokinase concentration.Methods:Twenty-four rabbits with thrombosed femoral artery were randomly divided into four treatment groups: urokinase alone (UK) group, ultrasound with non-targeted microbubble and urokinase (US+ M+ UK) group, platelet-targeted microbubble with urokinase (R+ UK) group, ultrasound with platelet-targeted microbubble and urokinase (US+ R+ UK) group. Thrombus-targeted microbubbles were injected through the ear vein and irradiated by ultrasound for 30 minutes, and the pulsed Doppler blood flow meter was used to continuously monitor the blood flow at 0 min, 10 min, 20 min, 30 min, 60 min, 90 min and 120 min after injection. At the same time, the changes in urokinase concentration were monitored, and the characteristics of blood flow and urokinase concentration changes were analyzed.Results:UK and US+ M+ UK groups failed to show recanalization at 120 minutes after treatment.In contrast, the US+ R+ UK and R+ UK groups both achieved persistent recanalization( P<0.001). Compared with the basal state. Both the R+ UK group and R+ UK+ US group showed a decrease at 60 minutes, and the difference was statistically significant( P<0.05). Conclusions:In the thrombolysis process of low-frequency ultrasound combined with a targeted contrast agent carrying urokinase, the targeting can make the local urokinase concentration of thrombus reach the highest level. At the same time, ultrasound and targeted microbubbles promote urokinase to enter the thrombus, and finally achieve the strongest thrombolytic effect.
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With the aging of social structure, the incidence of cardiovascular disease is increasing. Timely percutaneous coronary intervention (PCI) is an important method to treat acute coronary syndrome (ACS) and improve prognosis. Echocardiography has a prominent advantage in evaluating the ischemic myocardium and cardiac function in patients with ACS, therefore is of great significance in judging the development and prognosis. The applications of echocardiography in evaluating cardiac function changes after PCI were reviewed in this article.
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Objective To investigate the distribution characteristics and risk factors of intracranial and extracranial aterial lesions in Chinese patients with ischemic stroke . Methods In this multi‐center study ,2 310 continuously inpatients with ischemic stroke diagnosed in 20 stroke screening and prevention project base hospitals from June 2015 to M ay 2016 were enrolled . Carotid ultrasonography and transcranial color‐coded sonography or transcranial Doppler were performed in all patients to confirm the presence of cerebral artery stenosis or occlusion . According to the distribution of lesions ,the subjects were divided into 2 groups :the simple intracranial artery stenosis group and the simple extracranial artery stenosis group . T he difference of risk factors between the two groups was compared . Results Of the 2 310 patients with ischemic stroke ,1 516 ( 65 .6% ) had simple intracranial artery stenosis and 794 ( 34 .4% ) had simple extracranial artery stenosis . T he incidence of anterior circulation artery stenosis was higher in the group of intracranial artery stenosis than that in the extracranial artery stenosis group ( 68 .1% vs 48 .7% , P ＜0 .001) . Posterior circulation artery stenosis and combined anterior with posterior circulation artery stenosis were more common in patients with extracranial artery stenosis group than those in intracranial artery stenosis group ( 36 .4% vs 22 .1% ,14 .9% vs 9 .8% ;all P ＜0 .001) . Univariate analysis of risk factors for stroke showed that patients with intracranial arterial stenosis had a higher prevelence of hypertension , diabetes ,obesity ,and family history of stroke ,and their systolic blood pressure ,diastolic blood pressure , body mass index ( BM I) ,fasting blood‐glucose ,glycosylated hemoglobin ,triacylglycerol ,total cholesterol , and low‐density lipoprotein cholesterol were significantly higher than those in the extracranial arterial stenosis group ( all P ＜ 0 .05 ) . T he proportion of elderly ( ≥ 65 years old ) ,male and smokers in the extracranial arterial stenosis group was significantly higher than that in the intracranial arterial stenosis group ( all P ＜0 .05) . Multivariate logistic regression analysis showed that elderly ( ≥65 years old) ,male , and smoking history were independent risk factors for extracranial arterial stenosis ( OR＝ 2 .012 ,1 .637 , 1 .325 ,respectively ;all P ＜0 .05) . While hypertension ,diabetes ,less physical activity ,and high BM I levels were independent risk factors for simple intracranial arterial disease ( OR ＝ 1 .301 ,1 .252 ,1 .248 ,1 .030 , respectively ;all P ＜0 .05) . Conclusions There are significant differences in the distribution characteristics and risk factors of intracranial and extracranial aterial lesions in patients with ischemic stroke in China .
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Objective To evaluate the diagnosis value of three-dimensional speckle tracking echocardiography ( 3D-STE) in severe multi-vessel coronary stenosis at resting state . Methods Ninety-one patients with chest tightness ,chest pain ,other related clinical symptoms ,and suspected coronary heart disease were enrolled and underwent coronary angiography ( CAG ) , two and three-dimensional echocardiography(2D-STE ,3D-STE) . According to CAG results ,the patients were divided into 3 groups:severe multi-vessel stenosis group ( n = 38 ) ,severe single-vessel stenosis group ( n = 22 ) ,and control group ( n =31) . All patients underwent two and three-dimensional echocardiography .3D-STE was applied to obtain left ventricular global longitudinal strain ( 3D GLS) ,global circumferential strain ( 3D GCS) ,global area strain (3D GAS) and global radial strain(3D GRS) . Receiver operating curve analysis was conduct to evaluate the diagnosis value of 3D-STE in severe multi-vessel coronary stenosis at resting state . Results 3D GLS ,3D GCS ,3D GAS and 3D GRS were decreased in the severe multi-vessel group and single-vessel stenosis group compared to those in the control group( P <0 .05) ;and greater decreases was observed in the severe multi-vessel stenosis group( P <0 .001) . Furthermore ,3D GLS and 3D GAS in the severe multi-vessel stenosis group were lower than those in severe single-vessel stenosis group( P <0 .05) . ROC curve showed that the cutoff value for 3D GLS was ≤ -11％ with a measurement sensitivity of 84 .2％ and cutoff value for 3D GAS was ≤ -20％ with a measurement specificity of 79 .3％ . A joint diagnostic test showed that the sensitivity was increased when 3D GLS was combined with at least one other parameters . Conclusions 3D-STE shows a great diagnostic potential when applied to detect severe multi-vessel coronary stenosis . Moreover ,GLS and GAS may act as more valuable indicators .
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Objective To investigate the differences of distribution characteristics and risk factors of large artery lesions in patients with ischemic cerebrovascular disease in different age groups in order to provide the basis for the prevention and treatment of stroke in different age groups.Methods From June 2015 to May 2016,a total of 10 711 consecutive inpatients with transient ischemic attack (TIA) and ischemic stroke from 20 centers nationwide were enrolled.Each 10 years was used as an age group from 40 years.All the patients were divided into 5 age groups.The differences of the different risk factors for cerebrovascular disease among the 5 groups were compared.All patients were separated by gender.The chi square test was used to compare the incidences of large artery stenosis of the intracranial and external and anterior and posterior circulation,and the number of vascular lesions in the same sex in different age groups.Results (1) The risk factors of elderly patients were mainly hypertension,diabetes mellitus,and atrial fibrillation (χ2=61.938,χ2=13.349,and χ2=55.940;all P<0.01).The smoking history,family history of cerebrovascular disease,and obesity were more frequent among the young and middle-aged people (χ2=131.505,χ2=7.298,and χ2=100.911,all P<0.01).(2) The linear trend chi square test results showed that the proportion of multivessel diseases in female and male extracranial arterial lesions increased gradually with the increase of age.(χ2=54.799,χ2=161.370,all P<0.01).The proportion of multivessel diseases in the intracranial artery in female decreased gradually (χ2=5.328,P=0.021),and that in male did not have obvious trend of change (χ2=0.289,P=0.591).(3) The linear trend chi square test results showed that the incidence of simple intracranial arterial stenosis in female and male intracranial arterial stenosis decreased gradually with the increase of age (χ2=20.090,χ2=42.351,all P<0.01),and the incidence of simple extracranial arterial stenosis increased gradually (χ2=40.311,χ2=90.698,all P<0.01).The incidence of both intracranial and extracranial artery stenoses increased gradually (χ2=12.077,χ2=45.887,all P<0.01).The incidence of simple posterior circulation vascular stenosis increased gradually in female (χ2=16.434,P<0.01),but that did not have obvious trend of change in male (χ2=1.701,P=0.192).The incidence of stenosis of both anterior and posterior arteries in female and male increased gradually (χ2=4.587,P=0.032;χ2=35.156,P<0.01).Conclusions The distribution of atherosclerotic lesions in ischemic cerebrovascular disease of the different age groups was different.No matter female or male patients,the majority of the young and middle-aged patients were intracranial artery lesions,and the elderly patients were mainly extracranial artery lesions.The majority of elderly women had posterior circulation artery lesions.Understanding the characteristics in patients with intracranial arterial lesion in different age groups will help to develop individualized stroke prevention and treatment strategies for the population of different age groups.
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Objective To investigate the effect of serum lipid level on carotid artery stenosis in patients with ischemic cerebrovascular disease.Methods Using a multi-center cross-sectional study,10 711 consecutive inpatients with transient ischemic attack (TIA) or ischemic stroke diagnosed clearly in 20 stroke screening and prevention project base hospitals from June 2015 to May 2016 were enrolled.According to the results of carotid ultrasonography,1 560 patients with extracranial carotid artery stenosis rate≥50% screened were enrolled in the study.They were divided into a severe stenosis group (70%-99%) and a mild-moderate stenosis group (5.80 mmol/L (7.3%[43/586]vs.0.4%[4/974]) and LDL-C>3.12 mmol/L (26.3%[154/586]vs.10.0%[97/974]) in patients of the severe stenosis group were higher than those in the mild-moderate stenosis group (26.3%[154/586]vs.10.0%[97/974]).Conclusion The high LDL-C and TC levels may increase the incidence of severe carotid artery stenosis or occlusion.
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Objective To analyze the correlation between smoking and occurrence of intracranial artery stenosis.Methods From June 2015 to May 2016,a total of 10 711 inpatients with transient ischemic attack (TIA) or ischemic stroke from 20 basel hospitals of nationwide were enrolled using a cross-sectional study,76 patients with unknown smoking and smoking cessation years were excluded.Finally,a total of 10 635 patients were enrolled.Transcranial color coded sonography and/or transcranial Doppler were used evaluate the intracranial artery stenosis lesions.The basic risk factors for cerebrovascular disease (age,sex,smoking and smoking years,whether smoking cessation and years,hypertension,diabetes,hyperlipidemia,atrial fibrillation,and family history of stroke) were recorded.According to the different smoking years,the smoking years were divided into five groups:non-smoking,smoking time ≤10-year,11 to 20-year,21 to 30-year,and >30-year groups for trend chi square test.According to the different smoking cessation years in the smokers,the smoking cessation years were divided into four groups:non-cessation,cessation time 1 to 10-year,11 to 20-year,and >20-year groups for trend chi square test.The effects of different smoking years and different smoking cessation years on the occurrence of intracranial arterial stenosis were analyzed.Results The incidence of intracranial artery stenosis in the smokers (40.4%[1 433/3 547]) was significantly higher than that in the non-smoking patients (29.4%[2 085/7 088]).There was significant difference (χ2=128.850,P<0.01),and the incidence of cerebral infarction in the smokers (91.6%[3 250/3 547]) was significantly higher than the non-smokers (85.0%[6 027/7 088]).There was significant difference (χ2=92.328,P<0.01).Smoking was an independent risk factor for intracranial artery stenosis (OR,1.603;95%CI 1.456-1.765;P<0.01).With the increase of smoking years,the detection rate of intracranial arterial stenosis increased gradually (trend χ2=115.437,P<0.01).Whether giving up smoking had no significant effect on the incidence of intracranial artery stenosis in patients with ≥20 years of smoking (trend χ2=1.043,P=0.307).Conclusions Smoking is an independent risk factor for affecting intracranial artery stenosis;the risk of disease increases with the number of smoking years.Long-term smokers (≥20 years) cannot reduce the effect on intracranial artery stenosis,even if they give up smoking.
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Purpose To observe the thrombolytic effect of different ultrasonic frequencies combined with urokinase-containing targeted microbubble contrast agent on rabbit femoral artery,to explore the main influencing factors,and to determine the potential indicators related to recurrent embolism in the microcirculation.Materials and Methods Unilateral femoral arterial thrombosis models were established in the selected 72 New Zealand white rabbits,which were randomly divided into 12 groups,6 rabbits in each group.This study was performed on an experimental combination of three factors and different levels,including different ultrasonic frequencies (1.6,2.2,2.8 MHz),different ultrasonic irradiation time (30 and 60 min),and different urokinase dose (3 and 6 mg).Thrombolysis with urokinase-containing targeted microbubble was performed under low frequency ultrasonic assisted irradiation,the recanalization status of blood vessels was observed,and recurrent embolism in the microcirculation was confirmed by HE staining.Furthermore,rabbit blood samples were collected,with indicators,including 6-keto-prostaglandin F1a (6-keto-PGF1a),Thromboxane B2 (TXB2),P/T ratio (6-keto-PGF1a/TXB2) and P-selectin (SP) being detected.Results All the vessels were recanalized.There was no occurrence of recurrent embolism in the group with ultrasonic frequency of 2.2 MHz,radiation time of 30 min,and urokinase dose of 3 mg.Rabbits' blood vessels were observed to be not completely recanalized in other groups,accompanied with different degree of recurrent embolism in the microcirculation.6-keto-PGF 1 a content of the rabbits in the group without recurrent embolism obviously increased after thrombolysis,and the difference was statistically significant (P＜0.05).While,there was no statistical difference in other indicators (P＞0.05).Conclsion The thrombolysis with ultrasound frequency of 2.2 MHz,irradiation time of 30 min,and urokinase dose of 3 mg could achieve complete recanalization of blood vessels.Under the certain conditions of ultrasonic frequency,irradiation time and urokinase dosage,thrombus can be effectively dissolved.However,there may be risk of recurrent embolism in the microcirculation during thrombolysis process.The increase of 6-keto-PGF 1a content has a certain effect on reducing the formation of recurrent embolism in the microcirculation.
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Objective To evaluate gene transfection in liver , lung and kidney by ultrasound , microbubble and recombinant adenovirus mediated exogenous stromal cell derived factor-1α ( SDF-1α) gene transfer to the heart in rats with acute myocardial infarction( AMI) . Methods Forty AMI SD rats were randomly divided into control and experimental groups:myocardial infarction + ultrasound irradiation group (M+ U/control group , n = 10) ,and 3 experimental subgroups on the basis of pAd-EGFP/SDF-1α ( The biotin recombinant adenovirus expressing enhanced green fluorescent protein and SDF-1α) . Genes transfection length of time:1 day ,2 days and 3 days of transfection ( M +S1+U ,M+S2+U and M+S3+U group) . The expression of EGFP in liver ,lung and kidney were detected by laser scanning confocal microscopy at 7 days after administration . Results There was a little expression of EGFP in the liver ,lung and kidney in the drug delivery group and no expression in the control group .The differences in the expression of EGFP between all the gene delivery groups and the control group were statistically significant ( P <0 .05) . With the increase of the number of medication days , the target gene transfection increased slightly ,but there was no significant difference among the different drug delivery groups . Conclusions When the ultrasound ,microbubble and recombinant adenovirus mediated exogenous SDF-1αgene transfer to the heart in AMI rats ,liver ,lung and kidney tissues will also be transfected . However ,with the increasing of the days of administration , the transfection of target gene in non-target tissue produces only a slight accumulation . The transfection area of target gene in non-target tissue is not linear correlated with the days of administration .
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Objective To construct the uItrasound microbubbIes co-carrying recombinant adenovirus containing stromal cell derived factor 1 (SDF-1α) and bone morphogenetic protein 2 (BMP2),and to study the maximum efficiency of carrying adenovirus and the optimum proportion of double gene combined with ultrasound contrast agents.Methods Microbubbles were combined separately with recombinant adenovirus co-expression of enhanced green fluorescent protein and SDF-1α(pAd-EGFP/SDF-1α) as well as red fluorescence protein and BMP2 (pAd-RFP/BMP2) via biotin-streptavidin method,and the maximum efficiency of carrying DNA in microbubbles was detected.Three microbubbles with binary vectors were prepared by blending the two above-mentioned pAd at different ratio (1 ∶1,1 ∶ 2,2 ∶ 1) into the microbubbles.The microbubbles with binary vectors were evaluated though physiochemical properties,fluorescence microscope and flow cytometry to test the carrying rate of DNA in microbubbles.Results There was no significant difference in PH,average diameter and concentrations between targeted microbubbles and control group (P ＞0.05).The carrying efficiency of DNA increased with virus loads in microbubbles,but lowered if further increasing virus amount after reaching saturation.When the proportion of binary vectors and microbubbles was 1 ∶ 1,its efficiency of carrying SDF-1α gene and BMP-2 was approximately equal,and flow cytometry demonstrated that the positive rate of microbubbles labeled by both fluorescein isothiocyanate(FITC) and rhodamine was (65.6 ± 0.5)％.However,it was (59.0 ± 2.3)％ when their proportion was the 2 ∶ 1,which was significantly lower than those when other two proportions (1 ∶ 1 and 1 ∶ 2).Under the fluorescence microscope,the targeted microbubbles were equally surrounded by bright green or red fluorescence.Conclusions Ultrasound microbubbles of double genes carrying EGFP/SDF-1a and RFP/BMP2 is made successfully via biotin-streptavidin method.The optimal proportion of combining microbubbles with double gene is 1 ∶1,which can reveal the optimum load rate and stable combination.
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Objective To explore the express of von willebrand factor(vWF) and tissue factor(TF) in ultrasound combined with urokinase and RGDS-targeted microbubbles for recanalization of occluded rabbit femoral artery.Methods A total of 42 rabbits with platelet-rich thrombi in the femoral artery were randomized into 7 treatment groups (n =6 in each group):①ultrasound alone (US) group;②ultrasound,non-targeted microbubbles (US + M) group;③urokinase alone (UK) group;④ ultrasound,non-targeted microbubble and urokinase (US + M + UK) group;⑤ ultrasound,platelet-targeted microbubble (US + R) group;⑥ platelet-targeted microbubble,urokinase (R + UK) group;⑦ ultrasound,platelet-targeted microbubble and urokinase (US + R + UK) group.A total of 6 ml of infusion liquor of urokinase,RGDS and microbubbles (SonoVue) were mixed by the direct conjugation method,infusion via vein within 20 min.Ultrasound was conducted to lyse the clot for 30 min.The recanalization and the velocity tracing change of blood flow in thrombolytic process and the express of vWF and TF were evaluated at 120 min post treatment.Results For US,UK,US + M,US + R and US + M + UK groups,recanalization were failed.The R + UK and US + R + UK groups were partly recanalizated or completed recanalized (P ＜0.001).vWF and TF were positive in US,US + M,US + R and R + UK group.vWF and TF were negative in US + M + UK,UK and US + R + UK groups.Conclusions The combined effects of low frequency ultrasound and targeted microbubble combined with urokinase can inhibit the expression of vWF and TF,and then promote the thrombolysis,however it can affect the expression of vWF and TF after reperfusion.
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Objective To investigate the relationship between the content of stromal cell-derived factor-1 (SDF-1) in myocardium in different period of myocardial infarction and left ventricular function.Methods Twenty three Chinese miniature pigs were randomly divided into the experimental group and the control group.The swines in experimental group were prepared as acute myocardial infarction model by ligating anterior descending coronary artery and were randomly divided into 6 subgroups according to the different time points after infarction.The left ventricular end-diastolic diameter (LVDd),left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) were measured respectively.Global circumferential strain (GCS) and global radial strain (GRS) of left ventricle were measured.The content of SDF-1 were also measured by real-time quantitative PCR.Results Compared with the control group,SDF-1 levels were significantly elevated,and LVEF,LVFS,GCS and GRS were reduced.However,LVDd were significantly increased.The content of SDF-1 and GCS has a negative correlation (r =-0.580,P =0.000).Conclusions The content of SDF-1 in myocardial tissue have a certain relationship with GCS of left ventricular myocardium.
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BACKGROUND:Due to the different transplantation time after myocardial infarction, the homing ability of bone marrow mesenchymal stem cels to damaged tissues as wel as the repairing role wil be very different. OBJECTIVE:To explore the optimal window time for the homing of bone marrow mesenchymal stem cels to the myocardial tissue after myocardial infarction. METHODS: Eighteen Chinese miniature pigs were modeled by the ligation of left anterior descending coronary artery. BrdU-labeled bone marrow mesenchymal stem cels were injectedvia the coronary artery at 1 day, 3 days, 1 week, 2 weeks, 3 weeks, 4 weeks after modeling, respectively. Then, the animals were kiled at 3 days after cel transplantation to detect the home of bone marrow mesenchymal stem cels in the infarct zone. RESULTS AND CONCLUSION:BrdU-labeled positive cels with brown nuclei were visible at 1 day, 3 days, 1 week, 2 weeks, 3 weeks, and 4 weeks after myocardial infarction, especialy at 1 week after myocardial infarction (P < 0.05). It indicates that the best homing window for bone marrow mesenchymal stem cels was at week after myocardial infarction, when the stem cel transplantation is given to be able to promote myocardial repair.
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Objective To assess the value of the myocardial segment number of color change in the bull's eyes of three-dimensional speckle tracking echocardiography (3D-STE)in the detection of multi-vessel coronary stenosis at the resting state.Methods A total of 125 consecutive patients were enrolled and divided into the following three groups according to the coronary angiography(CAG):multi-vessel coronary stenosis group (n=48),single-vessel stenosis group(n =34)and control group (n =43).All patients underwent two-dimensional (2D)and three-dimensional echocardiography (3D)and three-dimensional speckle tracking echocardiography (STE).The bull's eyes of left ventricular 17 myocardial segments including longitudinal strain(LS),circumferential strain (CS),area strain(AS)and radial strain(RS)were acquired by 3D-STE.The homogeneous colors were regarded as normal wall motion myocardial segment (LS,CS,AS is a uniform red,RS for uniform blue ),the colors were uneven or shallower,or changes were regarded as abnormal wall motion myocardial segment.The myocardial segment number of color change in the bull's eyes can be calculated.Receiver operating characteristic (ROC ) curves were computed to determine optimal strain cutoff values to predict multi-vessel coronary stenosis.Results The myocardial segments of abnormal wall motion in the bull's eyes (LS,CS,AS,and RS)were significantly increased compared with the control group(P <0.001).In particular,the multi-vessel coronary stenosis group were dramatically increased than the single-vessel coronary stenosis group.Meanwhile,these parameters were higher in patients with multi-vessel coronary stenosis than in those with single-vessel coronary stenosis (P <0.05).ROC analysis demonstrated areas under the curve of 0.84 for 3D GLS,0.89 for 3D GCS,0.95 for 3D GAS,and 0.89 for 3D GRS.An optimal cutoff value of magnitude,sensitivity and specificity were LS,12,89.6%,76.7%;CS,11,89.6%,74.4%;AS,12,91.7%,88.4%;RS,13,81.2%,86.0%,respectively. Conclusions The myocardial segment number of color change in the bull's eyes by 3D-STE is useful to detect multi-vessel coronary stenosis,where in GAS are more valuable indicators with higher sensitivity and specificity.
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BACKGROUND:Stromal cel-derived factor-1 (SDF-1) is one of the most powerful chemokines in myocardial infarction region and plays a particularly pivotal role in the homing of stem cels to an injured myocardium and promoting angiogenesis. On the other hand the microbubble and acoustics active substances carrying targetable ligands can be prepared into targeted ultrasound contrast agents that can be combined with living cels used for molecular imaging. The key of ultrasonic molecular imaging is to find imaging targets, and to successfuly prepare targeted ultrasound contrast agent which can be combined with the imaging target specificaly and efficiently. OBJECTIVE:To prepare and evaluate targeted microbubble contrast agents with SDF-1 monoclonal antibody. METHODS:Targeted microbubble contrast agent with SDF-1 monoclonal antibody was prepared using the biotin-streptavidin method. The physiochemical properties of targeted microbubble contrast agent were evaluated by appearance, pH, particle diameter, optical and fluorescence microscope and flow cytometry test. Four minipigs underwent ligation of the left anterior descending coronary artery to complete the establishment of acute myocardial infarction model, and another two minipigs were subject to thoracotomy but no ligation of the coronary artery. Then, al animals were injected with microbubble contrast agents. The stability of microbubbles was assessed by immunofluorescence testin vivo. RESULTS AND CONCLUSION:SDF-1 and microbubbles were combined by biotin-streptavidin method.In vitro appearance of the contrast agent was translucent yelow or green, and stratified after standing. pH vaule was 7.02±0.12 for non-targeted contrast agent and 6.10±0.19 for targeted microbubble contrast agent. Under the fluorescence microscope, the distribution and size of targeted microbubbles were uniform, and the microbubbles were surrounded by bright and ring shaped green fluorescence that had no changes after highly shaking. The diameter of microbubbles was (2 422.62±238.82) nm after carrying the SDF-1 antibody. Flow cytometry results showed that the carrying rate of targeted contrast agents was stable in different periods.In vivo test showed that targeted microbubbles gathered in vascular endothelial cel surface after acute myocardial infarction. These findings indicate that the targeted microbubble contrast agent carrying SDF-1 monoclonal antibody prepared by biotin-streptavidin method can be combined with vascular endothelial cels, and the binding rate is high and stablein vitro.
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BACKGROUND:Occluder closure of atrial septal defect exhibits clear function, safety and efficiency advantages ＜br> OBJECTIVE:Using real-time three-dimensional echocardiography (RT-3DE) technique to evaluate the effect of atrial septal defect occlusion using different occluders on left ventricular structure and motion of the mitral annulus. ＜br> METHODS:Thirty-seven cases diagnosed as atrial septal defect underwent atrial septal defect occlusion, including 20 males and 17 females, aged 20-60 years. The occluder was chosen individual y according to defect size and edge hardness. Conventional and RT-3DE examinations were performed at 1 day prior to occlusion, 1 and 3 months after occlusion. ＜br> RESULTS AND CONCLUSION:Four of 37 patients were withdrawn from the study because of poor RT-3DE results. The other 33 patients harvested good occlusion results. At 1 and 3 months after occlusion, left ventricular end diastolic volume, left ventricular end systolic volume, left atrial end diastolic volume, left atrial end systolic volume were significantly increased (P＜0.05). Moreover, the more increase in these parameters occurred at 3 months after occlusion (P＜0.05). There were no significant changes in left ventricular ejection fraction and mitral annular displacement at three different time points. Left ventricular volume change rate and left atrial volume change rate were positively correlated to the type of occluders, while there was no correlation between endocardial cushion stump and mitral annular displacement. These findings suggest that atrial septal defect occlusion can increase the volume of the left ventricle and left atrium, but exhibit no effect on the motion of the mitral annulus.
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Objective To evaluate the difference of myocardium strain between myocadial infarction and ventricular aneurysm (VA) by two-dimensional speckle-tracking imaging in rabbits.Methods 26 healthy New Zealand white rabbits were enrolled in this study,6 were put into the control group and 20 in the experimental group.models of myocardial infarction concomitant with VA were prepared by the ligation of the middle segment of left anterior descending artery and left circumflex artery.At 4 weeks after the procedure,according to the pathological inspect and echocardiography for whether VA formed,the experimental animals were divided into the VA group and the myocadial infarction group.Echocardiography was performed to measure the LV cavity size and cardiac function.Radial strain rate (SrR) and circumferential strain rate(SrC) indexes were measured by 2D-STI software for each animal at the level of apex in left ventricular short-axis view,and then calculated the strain rate decrease percentage in each segment.Results 1)Compared with the control group,SrR-S,SrR-E,SrR A,SrC-S,SrC-E,SrC-A in all segments were reduced significantly in the VA group and the myocadial infarction group (P ＜ 0.05),the VA group was the most significant.2)Compared with the myocadial infarction group,the strain rate decrease percentage of SrR-S,SrR-E,SrR-A,SrC-S,SrC-E,SrC-A in all segment had significant in the VA group.Comparison between the each section,the strain rate decrease percentage of SrR-Santerior wall,SrR-Sateral wall,SrC-Santerior wall,SrC-Slateral wall were the most significant.3)There were the tighter relationship between the strain rate decrease percentage of SrR-Santerior wall,SrC-Santerior wall,SrR-Slateral wall,SrC-Slateral wall and left ventricular ejection fraction (r =0.82,0.72,0.75,0.71,repectively,all P ＜ 0.05).4) The ROC curve analysis showed that when the strain rate decrease percentage was 60％ as the critical point,the strain rate decrease percentage of SrC-Santerior wall,SrC-Slateral wall,SrR-Santerior wall,SrR-Slateral wall had a sensitivity of 83.30 ％,84.40％,83.30％,67.70％％ and a specificity was 73.60％,78.20％％,69.70％,83.30％ for prognosis ventricular aneurysm,repectively.Conclusions After ventricular aneurysm formation,anterior and lateral wall myocardial strain were give priority to the myocardial mechanics reconstruction,thus systolic myocardial strain rate decrease percentage can be important indicator of infarction myocardial developing into ventricular aneurysm.
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ObjectiveTo evaluate the influence on left ventricular(LV) twist,and the relationship between LV twist and function in the rabbits with ventricular aneurysm formed after myocardial infarction by two-dimensional ultrasound speckle tracking imaging.MethodsTwenty-six healthy rabbits were divided into two groups,six as control group,twenty as experimental group.The model of myocardial infarction and ventricular aneurysm were established by ligaturing left anterior descending coronary artery and left circumflex artery.After four weeks,according to the pathological examination of whether ventricular aneurysm formed or not,the experimental group was divided into myocardial infarct group and ventricular aneurysm group.Echocardiography was performed to measure rotations (at the levels of mitral annulus and apex in LV short-axis view),LV twist,left ventricular cavity size and function.ResultsCompared with the myocardial infarct group,LV end-diastolic diameter(LVEDD) and LV end-diastolic volume(LVEDV) were larger in the ventricular aneurysm group,but LV ejection fraction (LVEF),LV fractional shortening (LVFS),apical rotation and LV twist were lower in the ventricular aneurysm group than the myocardial infarct group.Both apical rotation and LV twist had shown a great correlation with LVEF.The conclusion was also shown in the ROC curve that sensitivity and specificity of diagnosis cardiac dysfunction were 76.9％ and 80.0％ respectively when the apical rotation was 1.21°.Conclusions There was a closely relationship between the change of apical rotation and the LV systolic function.When the apical rotation dropped to 1.21°,an apparent decline of LV systolic function was implied.
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Objective To measure the parameters of mitral valve leaflets and mitral annulus in patientswithmildmitralregurgitation( MR )byreal timethree-dimensionaltransesophagealechocardiography (RT-3D-TEE),and explored the mechanism of MR.MethodsFifty-seven MR subjects were selected and twenty-eight subjects without mitral regurgitation were served as control group,all subjects were examined by RT-3D-TEE and acquired image,mitral valve quantification (MVQ) software was used for post-processing.Mitral annulus parameters (H/DAIPm,E2D,θAv-Mv,mitral annulus θnpa) and mitral valve leaflets parameters(A3DE,L2DAIPm,VA1-3tentVp1-3tentVtentHtentθnpa ) at the end of systolic were measured.The results of two groups were compared,and the most affected parameters to mild mitralregurgitation were selected.Results Compared with control group,VA3tent was decreased,mitral annulus θnpa and L2DAIPm increased,and the mitral valve leaflets θnpa was independently correlation factor of mild mitral regurgitation.ConclusionsThe mitral annulus geometry to flat in subjects with mild MR,the mitral valve local area is increased in subjects with mild MR,the mitral valve leaflets θnpa is independently correlation factor of mild mitral regurgitation.
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Objective To evaluate left atrial appendage regional function and movement changes of systolic and diastolic in patients with atrial fibrillation by speckle tracking imaging(STI) and real-time three-dimensional transesophageal echocardiography(RT-3D TEE).Methods Sixty-seven patients underwent RT-3D TEE was divided into 24 controls,22 paroxysmal atrial fibrillation,21 persistent atrial fibrillation.Left atrial appendage was divided into basal,middle and apical segment.Left atrial appendage emptying fraction of the overall (LAA-EF),basal emptying fraction (B-EF),middle emptying fraction (M-EF) and apical emptying fraction (A-EF) was measured by three-dimensional volume measurement.Each segment systolic strain rate (SRS) and diastolic strain rate (SRD) was measured by STI.Results LAA-EF,B-EF,M-EF,A-EF of paroxysmal atrial fibrillation and persistent atrial fibrillation group were lower than those of the control group,and persistent atrial fibrillation group was the lowest in the three groups.Compared with the control group,SRS and SRD of left atrial appendage basal,middle,apical segment was lower in paroxysmal atrial fibrillation group and persistent atrial fibrillation group,and persistent atrial fibrillation group decreased more significantly.Conclusions Paroxysmal atrial fibrillation and persistent atrial fibrillation can lead to left atrial appendage global or local systolic and diastolic function to reduce,and persistent atrial fibrillation decreased more significantly.