Prevalence of Lying Flat behaviors and its association with depressive symptoms among college students from three provinces and cities in China / 中国学校卫生

Objective@#To understand the prevalence of Lying Flat behaviors and its association with depressive symptoms among Chinese college students, so as to provide a scientific basis for promoting the physical and mental health development of adolescents.@*Methods@#From July to October 2023, three universities were selected through convenient sampling from Jiangxi Province, Liaoning Province and Beijing City, respectively. Selfdesigned questionnaire links were distributed on campus to collect basic information and Lying Flat behaviors among college students, and the Patient Health Questionnaire-9 (PHQ-9) was utilized to screen for students with depressive symptoms. Finally, a total of 4 225 valid questionnaires were obtained. Chisquare was used to compare of report rates of Lying Flat behaviors across different demographic characteristics. Ordered Logistic regression analysis was used to explore the association between Lying Flat behaviors and depressive symptoms, with Z test used to assess variations in the strength of associations.@*Results@#The reporting rates of academic, life, and social Lying Flat were 32.7%, 17.8% and 17.5%, respectively. And 6.7% of the participants were found of all three Lying Flat behaviors simultaneously.Among college students with three Lying Flat behaviors, the constituent ratios of no, mild, moderate and above depressive symptoms were 9.9%, 30.5% and 59.6%, respectively. Additionally, college students who had three Lying Flat behaviors were more likely to show mild, moderate and above depressive symptoms [OR(95%CI)=2.49(1.60-3.87), 7.69(5.01-11.79), P<0.01].@*Conclusions@#Academic Lying Flat behavior is most prevalent among college students. Academic, life and social Lying Flat behaviors are all significantly positively correlated with depressive symptoms. Attention should be paid to the Lying Flat behaviors and college students psychological health conditions to promote their physical and mental health development.

Association between HLA-B*27:04 and genetic susceptibility to ankylosing spondylitis in Hunan Province / 中南大学学报(医学版)

Objective:Human leukocyte antigen(HLA)B27 is a susceptibility allele of ankylosing spondylitis(AS),and HLA-B27 antigen typing is an important indicator for clinical diagnosis of AS,but current typing methods such as sequence specific primer polymerase chain reaction(PCR-SSP)still possess limitation.Therefore,this study aims to analyze the correlation between B27 subtypes and susceptibility to AS in Hunan Province by applying high-resolution polymerase chain reaction-sequence-based typing(PCR-SBT). Methods:Peripheral blood of 116 patients with suspected AS(suspected AS group)and 121 healthy volunteers(control group)admitted to the Second Xiangya Hospital from January 2020 to December 2020 were collected for HLA-B genotyping by PCR-SBT.Among the patients in the suspected AS group,23 patients were finally diagnosed with AS(confirmed AS group),and the remaining 93 undiagnosed patients served as the non-confirmed AS group.PCR-SBT and PCR-SSP were used to detect HLA-B27 typing in 116 patients with suspected AS,and the results of the 2 methods were compared. Results:The HLA-B27 allele frequency in the suspected AS group was significantly higher than that in the control group[11.63%vs 2.48%;P<0.001,odds ratio(OR)=5.18,95%confidence interval(CI)2.097 to 12.795].B*27:04,B*27:05,B*27:06,and B*27:07 were detected in the suspected AS group and the control group.The frequency of the B*27:04 allele in the suspected AS group was significantly higher than that in the control group(9.48%vs 1.24%;P<0.001,OR=8.346,95%CI 2.463 to 28.282).The positive rate of B27 in the suspected AS group and the confirmed AS group(B27+/+ and B27+/-)was significantly higher than that in the control group(χ2=16.579,P<0.001;χ2=94.582,P<0.001,respectively).Among the confirmed AS group,21 were HLA-B27 carriers,and the B27 positive rate in the confirmed AS group was 91.3%.PCR-SBT could achieve high resolution typing of the HLA-B gene locus,with higher sensitivity,specificity,positive predictive value,negative predictive value,and accuracy than PCR-SSP. Conclusion:PCR-SBT typing analysis shows a strong correlation between HLA-B * 27:04 and AS in Hunan province.The PCR-SBT method can be used as the preferred option for the auxiliary diagnosis of clinical AS.

Value analysis of ultrasound-guided fine needle and core needle biopsy of cervical lymph nodes in diagnosis / 中国医师杂志

Objective To compare the value of ultrasound-guided fine-needle aspiration (FNA) and core needle biopsy (CNB) in diagnosing benign and malignant cervical lymph nodes.Methods A retrospective analysis was performed on 88 patients who received biopsy for cervical lymph node enlargement from January 2015 to May 2017.FNA (n =39) or CNB (n =49) were performed respectively to compare the sensitivity,specificity and accuracy of the two methods in diagnosing benign and malignant cervical lymph node enlargement.Results 84.6％ (33/39) of FNA cases were successfully collected,and 98％ (48/49) of FNA cases were successfully collected for definite pathological diagnosis (P =0.000).The sensitivity,specificity and accuracy of FNA and CNB in diagnosing malignant cervical lymph nodes were 90.9％ and 97.2％,94.1％ and 100％,92.3％ and 98％,respectively.Compared with FNA,there were statistically significant differences in sensitivity,specificity and accuracy in differentiating benign and malignant lymphatic lesions in cervical enlargement (P ＜0.01).The sensitivity and specificity of FNA and CNB in diagnosing cervical lymph node metastatic carcinoma were 100％ and 100％,95.2％ and 100％.Compared with FNA,there was no statistically significant difference in the sensitivity to the diagnosis of cervical lymph node metastatic carcinoma (P =0.102).Conclusions CNB is superior to FNA in sensitivity,specificity and accuracy in diagnosing cervical lymphadenopathy.However,when metastatic cancer was diagnosed,FNA was not significantly different from CNB in sensitivity (P =0.102),and FNA was recommended as the first choice.

Effects of Fengliao-Changweikang in Diarrhea-predominant Irritable Bowel Syndrome Rats and Its Mechanism Involving Colonic Motility

BACKGROUND/AIMS: This study was designed to investigate the effect of Fengliao-Changweikang (FLCWK) in diarrhea-predominant irritable bowel syndrome (IBS-D) rats and explore its underlying mechanisms. METHODS: IBS-D model rats were induced by neonatal maternal separation (NMS) combined with restraint stress (RS). In in vivo experiments, the model rats were randomly divided into 5 groups: NMS + RS, FLCWK (low dose, middle dose, and high dose), and pinaverium bromide. The normal control (no handling) rats were classified as the NH group. The therapeutic effect of FLCWK was evaluated by fecal characteristics, electromyographic response and abdominal withdrawal reflex scores. In in vitro experiments, the model rats were randomly divided into 2 groups: NMS + RS, FLCWK (middle dose), and no handling rats were used as the NH group. The differences in basic tension and ACh-induced tension of isolated colonic longitudinal smooth muscle strips (CLSMs) among the 3 groups were observed. In addition, different inhibitors (nifedipine, TMB-8, L-NAME, methylene blue, and 4-AP) were pretreated to explore the underlying mechanisms. RESULTS: In in vivo experiments, fecal characteristics, electromyographic response, and abdominal withdrawal reflex scores significantly improved in the FLCWK group, compared with the NMS + RS group. In in vitro experiments, the basic tension and ACh-induced tension of CLSMs in IBS-D rats were significantly inhibited by FLCWK. After pre-treatment with different inhibitors, the ACh-induced tension of CLSMs in each group showed no significant difference. CONCLUSIONS: FLCWK manifested curative effect in IBS-D rats by inhibiting colonic contraction. The underlying mechanisms may be related to regulatory pathway of nitric oxide/cGMP/Ca2+ and specific potassium channels.

The effect of different localizing techniques in guiding botulinum toxin injection in the treatment of lower limb spasticity in cerebral palsy children / 中华物理医学与康复杂志

Objective To observe the effect of free muscle localization and ultrasound-guided injection of botulinum toxin type A (BTX-A) combined with rehabilitation training on lower limb spasm of cerebral palsy children.Methods Sixty-one cerebral palsy children with lower limb spasticity were randomly divided into a manual localizing group (31 cases) and an ultrasound-guided group (30 cases).The children of both groups underwent BTX-A injection at adductors,hamstrings and calf triceps.The former group was injected with bare hands,while the latter was injected under the guidance of ultrasound.Both groups were administered with rehabilitation training from the 3rd day onwards after injection.Before and 12 weeks after the injection,the modified Ashworth scale (MAS) and gross motor function scale (GMFM) were used to evaluate the lower limb spasticity and function in 2 groups.Results Before the injection,there was no significant difference between the 2 groups in terms of MAS and GMFM scores (P ＞ 0.05).However,12 weeks after the injection,the average MAS scores of the two groups decreased,and that of the ultrasound-guided injection group (1.43 ±0.50) was significantly lower than that of the manual localizing group (1.77 ± 0.56).After the injection,the average GMFM scores of both groups increased,and that of the ultrasound-guided injection group was significantly higher than the manual localizing group (67.10 ± 11.25).Conclusion Ultrasound-guided injection of BTX-A with intensive rehabilitation training can significantly reduce the lower limb spasticity in children with cerebral palsy,and increase their motion of joint and motor function,and improve their posture and gait.

Expression and Clinic Significance of Serum DJ-1 in Ovarian Cancer / 天津医药

Objective To investigate serum DJ-1 expression and its significance in ovarian cancer. Methods The expression levels of DJ-1 protein were detected by double antibody sandwich method in 52 cases of ovarian tumors (9 cases of benign ovarian tumors, 5 cases of borderline ovarian tumors and 38 cases of ovarian cancer,ovarian tumor group and 20 non-ovarian tumors (control group). Results The expression of DJ-1 protein was lower in the control group than that in ovarian tumor group (P0.05). Conclusion DJ-1 might be used as a serum marker in the diagnosis of ovarian cancer. It might be involved in the pathogenesis of ovarian cancer,and could predit the development and prognosis of ovarian cancer.

Evaluation of left ventricular geometry and function by echocardiography in patients after arterial switch operation / 中华超声影像学杂志

Objective To study the early and mid-term outcome in terms of left ventricular(LV)geometry and function in patients with transposition of great arteries with intact ventricular septum (TGA/IVS) undergoing arterial switch operation.Methods Twenty patients were followed up and divided into 2 groups according to age:the earlier group and the later group.Age and sexual matched controls were also designed as control group 1 and control group 2.LV posterior wall thickness(PWTd),dimension(LVIDd)and length(L) at end diastolic phase,LV end-diastolic volume (EDV),end-systolic volume (ESV),ejection fraction (EF),mitral valve early (E) and late (A) inflow velocities and E/A,isovolumic relaxation time (IVRT) were obtained by two-dimensional echocardiography,normalized isovolumic relaxation time (IVRTn),wall thickness index (PWTd/LVIDd) and LV geometry index(LVIDd/L) were calculated,and these indexes between groups were compared.Results ①Compared with control group 1,PWTd in earlier group was higher [(0.41 + 0.06)cm vs (0.36 + 0.05)cm,P =0.022],but LVIDd had no significant statistical difference [(2.08 + 0.21)cm vs (2.21 + 0.23)cm,P =0.117],indicating PWTd/ LVIDd differed between groups(0.20 + 0.04 vs 0.16 + 0.01 P =0.001).②No abnormalities were observed in later group.③Compared with different age groups in TGA,EDV,ESV,L,LVIDd,PWTd were significantly higher in later group(P =0.000).There were obvious correlations between EDV,ESV,L,LVIDd and examined age (r =0.90,0.83,0.73,0.90,P =0.000,R2 =0.809,0.694,0.528,0.808) while there were no significant correlation between PWTd and examined age(r =0.56,P =0.000,R2 =0.309).Conclusions Early after operation,LV is undergoing hypertrophy or hyperplasia in TGA/IVS,but will recover in the mid-term period,and the function is normal all the time indicating that the LV myocardium may avoided irreversible pathological changes if operated in time.All in all,LV develops well in mid-term period.

Evaluation of left ventricular myocardial function in patients with severe aortic stenosis by two-dimensional speckle tracking imaging / 中华超声影像学杂志

Objective To evaluate left ventricular(LV) systolic function by two-dimensional speckle tracking imaging(2D-STI) in severe aortic stenosis(AS) patients.Methods Standard echocardiography and 2D-STI examinations were performed in a total of 54 subjects including 26 consecutive patients with severe AS with LV ejection fraction(LVEF) ≥50％ and 28 controls.2D-STI including systolic longitudinal strain (LS) and strain rate(LSr) were assessed from the apical 4-chamber,3-chamber and 2-chamber views,the circumferential strain(CS) and strain rate(CSr),radial strain(RS) and strain rate(RSr) were measured from the standard short axis views (averaging 6 segments per view).The above parameters of AS groups were compared with those of normals.The repeatability of LVEF,LS and RS was evaluated in 6 AS patients and 6 normal volunteers selected at random from the investigation.Results ① There was no significant difference between AS group and control group in LVEF,LV end-diastolic dimension(LVEDD),LV endsystolic dimension (LVESD) and midwall fractional shortening (mwFS) (P ＞ 0.05).② Significant differences were detected between the two groups.LS,RS,CS,LSr,RSr,and CSr were obviously decreased in AS group(P ＜0.05).③The repeatability of LVEF,LS and RS was good by consecutive measurement of identical and independent observers.Conclusions Despite the presence of normal LVEF,the LV systolic function is impaired in severe AS patients.

Evaluation of left ventricular bulk rotation and untwisting in transplanted hearts using two-dimensional speckle tracking imaging: a preliminary study / 中华超声影像学杂志

Objective To evaluate the changes of left ventricular (LV) bulk rotation and untwisting in transplanted hearts using 2-dimensional speckle tracking imaging(STI).Methods Basal and apical LV short-axis images were acquired in 15 heart transplant recipients 3 months post surgery(HT group) and 56 healthy control subjects.Basal and apical rotation versus time profiles were drawn using 2-dimensional STI software.Appropriate values were chosen from the dataset obtained and compared between two groups.Results ①Compared with the control group,the heart rate,anterior-posterior diameter of left atrium,enddiastolic interventricular septum thickness,left ventricular posterior wall thickness,isovolumic relaxation time and E/e ratio were significantly increased,e and a values were decreased significantly in HT group (P ＜ 0.05).② No significant difference was noticed in the peak degrees of LV bulk rotation,the degrees of LV bulk rotation at the time of aortic valve closure and mitral valve opening (P =0.700,0.984,0.495,respectively) between 2 groups.In both groups,systolic rotation reached its maximum at end-systole [(96.1 ± 8.4) ％ in HT group vs (100.5 ± 6.3) ％ in control group,P =0.065].③Significant decreases in untwisting rate and trend untwisting variables were observed in the HT group(P ＜0.001).Conclusions 3 months after transplanted,left ventricular bulk rotation of cardiac allografts remained normal,and significant decreases in both untwisting rate and trend untwisting variables showed that the diastolic function of cardiac allografts was impaired.

Establishment and assessment of orthotropic and heterotrophic valve implantation models in goat with minimally invasive methods / 中华胸心血管外科杂志

Objective To establish and evaluate 3 kinds of minimally-invasive valve implantation model in vivo.Methods A novel tissue engineered heart valve(TEHV) manufactured by branched polyethylene glycol cross-linked acellular porcine valve and a minimally-invasive valve implantation system according to the design of Corevalve revalving system were adopted.After anesthesia,18 adult male goats were randomly divided into 3 groups: the ulrasound-directed orthotropic group (group A,n =6),angiography-directed orthotropic group (group B,n =6) and direct-released heterotopic group (group C,n =6),and all received minimally-invasive valve implantation orthotropically or heterotopically.4 weeks later,the valvular function was evaluated by CTA and/or echocardiography.Results All 3 kinds of caprine model were successfully constructed.The operation success rate of each group was A: 66.7％,B: 50.0％ and C: 100.0％,respectively(multiple x2 analysis,group A and B P ＞0.05; group A and C,group B and C,P ＜0.05).The operation-time of each group was A: (79 ± 18) min,B:(61 ±23) min,C: (45 ± 15) min(one-way ANOVA,P ＜0.05).The survival rate at4 weeks was A: 100％,B: 100％ and C: 83.3％ (multiple x2 analysis,P ＞ 0.05).Echocardiography and CTA proved the short-term function of implanted TEHV was satisfactory.Conclusion All 3 kinds of caprine valve implantation model can be established without cardiopulmonary bypass and blood transfusion.The devices and equipments required in group A is relatively simple,but the procedure cost longer time for it is hard to determine the right position by ultrasound.The application of angiography made the positioning much easier in group B while the procedure had to be performed in specific operation room with angiographic apparatus.Group C did rely on neither special equipments nor complex operation,but the valve leaflets cannot work normally,so this model was only suitable for testing in vivo characteristics such as biocompatiblities.

Mouse melanoma cell line B16F10-derived conditioned medium inhibits sodium L-ascorbate-induced B16F10 cell apoptosis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of mouse melanoma cell line B16F10-derived conditioned medium on the apoptosis of B16F10 cells.</p><p><b>METHODS</b>B16F10 cells were cultured in high-glucose DMEM in the presence of 10% fetal bovine serum, and upon cell confluence, the growth medium was replaced with serum-free high-glucose DMEM. After 8 h, the medium was collected and infiltrated to serve as the conditioned medium. B16F10 cells cultured in normal growth medium or the conditioned medium were exposed to 10 mmol/L sodium L-ascorbate, and the cell apoptosis was analyzed. The ingredients in the conditioned medium with relative molecular mass less or more than 5 000 were extracted to assess their effect on sodium L-ascorbate-induced cell apoptosis.</p><p><b>RESULTS</b>The conditioned medium for B16F10 cells significantly inhibited cell apoptosis induced by sodium L-ascorbate, and the effective ingredients in the medium showed a relative molecular mass below 5,000.</p><p><b>CONCLUSION</b>Mouse melanoma cell line B16F10-derived conditioned medium can suppress sodium L-ascorbate- induced apoptosis of B16F10 cells, and the ingredients with relative molecular mass less than 5 000 are responsible for this effect.</p>

Effect of lentivirus-mediated nestin gene silencing on metastatic potential of human melanoma cell line UACC903 in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of lentivirus-mediated RNA interference (RNAi) of nestin on the metastatic potential of human melanoma cell line UACC903.</p><p><b>METHODS</b>A lentiviral vector for RNAi targeting the coding region of human nestin mRNA (nestin-RNAi-LV) and another control vector containing a nonsense sequence were constructed. The vectors were transfected into UACC903 cells, and nestin expression in the cells was detected by RT-PCR, immunofluorence assay and Western blotting. The invasive ability and migration of the transfected UACC903 cells was evaluated using Transwell and scrape assay, respectively. Fluorescence assay was used to examine the expressions of E-cadherin, N-cadherin and β-catenin in the cells.</p><p><b>RESULTS</b>The lentiviral vector nestin-RNAi-LV was constructed successfully. Compared with the control vector, nestin-RNAi-LV resulted in obviously reduced expression of nestin mRNA and protein, lowered migration ability of UACC903 cells, and reduced cell adhesion and invasiveness (P<0.05).</p><p><b>CONCLUSION</b>Lentivirus-mediated nestin RNAi can specifically inhibit nestin expression to cause decreased cell migration and invasiveness of human melanoma cell line UACC903.</p>

Evaluation of right ventricular global longitudinal function in patients with tetralogy of fallot by two-dimensional ultrasound speckle tracking imaging / 华中科技大学学报（医学）（英德文版）

Quantification of right ventricular (RV) volume and function remains a challenge because of RV complex geometry by conventional echocardiography. The purpose of this study was to assess RV global longitudinal function in patients with tetralogy of Fallot (TOF) by 2-dimensional ultrasound speckle tracking imaging (STI). Thirty-eight patients with TOF were enrolled in this study and divided into child group (n=25) and adult group (n=13) according to age. Thirty-eight age- and sex-matched normal subjects were selected as control groups including child control group (n=25) and adult control group (n=13). RV global longitudinal peak systolic strain (GLS), strain rate (GLSR(s)), early diastolic strain rate (GLSR(e)) and late diastolic strain rate (GLSR(a)) were measured in all subjects by STI from the apical 4-chamber view and compared between groups. Furthermore, the main factors affecting the RV global longitudinal functional parameters were assessed. Compared with those in controls, RV GLS, GLSR(s) and GLSR(e) were significantly reduced in patients with TOF (P0.05). The diameter of right ventricle, main pulmonary artery and ventricular septum defect had correlations with RV GLSR(s) (r ( 1 )=-0.490, r ( 2 )=0.580, r ( 3 )=-0.528, respectively, P<0.05 for all). Tricuspid annular plane peak systolic velocity (Sm) was the independent predictor of RV global strain and strain rate (beta(1)=0.355, P (1)=0.031, beta(2)=0.307, P (2)=0.021). RV global longitudinal function is decreased in patients with TOF, especially in adult patients. STI is a sensitive and accurate technique in RV global functional assessment.

Two-dimensional speckle tracking imaging quantitative assessment of left ventricular global and regional myocardial function in normal rats / 中国医学影像技术

Objective To investigate the value of two-dimensional speckle tracking imaging (2D-STI) in assessing left ventricular global and regional myocardial function in normal rats. Methods Echocardiography was performed during low-dose dobutamine stress in 20 normal adult male Wistar rats. High frame rate of 2D images were recorded from the left ventricular short-axis views at the papillary muscle level. Peak systolic radial strain (PRS) and circumferential strain (PCS) of each segment, left ventricular global peak systolic radial strain (G_(PRS)) and circumferential strain (G_(PCS)) were measured at EchoPAC work station. Left ventricular internal diameter at diastole (LVIDd), systole (LVIDs), fractional shortening (FS) and ejection fraction (EF) were measured with anatomical M-model echocardiography. Dynamic changes of each index during stress experiment were observed. The correlations between EF and left ventricular global two-dimensional strain (G_(PRS), G_(PCS)) were analyzed respectively. Results PRS was similar in all segments of mid-ventricular in short-axis view (P>0.05) at baseline, while PCS of each segment showed heterogeneity, with the anteroseptal and anterior wall showing the largest value and the inferior wall showing the lowest value (P0.05). Conclusion With good reproducibility, 2D-STI can noninvasively and easily assess global and regional left ventricular myocardial deformation of normal rats at rest and during low-dose dobutamine stress.

Diagnosis of the criss-cross heart by echocardiography / 中华超声影像学杂志

Objective To explore the value of echocardiography in the diagnosis of the criss-cross heart. Methods The echocardiographic results of 6 patients with the criss-cross heart were reviewed retrospectively. The echocardiographic characteristics were analyzed and compared with the surgery results in 4 operated cases. Results The 6 cases were interpreted as representing a criss-cross heart with solitus atria,D-loop ventricles and concordant atrioventricular connections. The ventriculo-arterial alignments of 5 cases were abnormal including double outlet right ventricle with anterior aorta in 2 and transposition of the great arteries in 3 while 1 patient had concordant connection. The following principal characteristics were tilting the transducer from posterior to anterior could demonstrate the connection of the left-sided left atrium and the right-sided left ventricle through mitral valve at first. The more anterior angulation of the transducer then showed the right-sided right atrium was connected to the left-sided right ventricle through tricuspid imaging displayed the two atrial outflows crossed each other without mixing at atrioventricular valve level.right ventricle often occured. The echocardiographic diagnosis of the criss-cross heart and its associated cardiac abnormalities were confirmed by surgery in 4 cases except 1 persistent left superior vena cava was missed. Conclusions The invisibility of a standard 4-chamber view in any cut was very characteristic in the echocardiographic diagnosis of the criss-cross heart. The definitive appearance was the separate display of the two ventricular inlets and the crossed atrioventricular connections with each atrium emptying into the contralateral ventricle by continuous subxiphoid or apical scanning. The transthoracic echocardiography can diagnose this rare heart disease and associated cardiac abnormalities accurately.

Assessment of regional left ventricular myocardial function in rats after acute occlusion of left anterior descending artery by two-dimensional speckle tracking imaging / 华中科技大学学报（医学）（英德文版）

This study evaluated the change in regional left ventricular myocardial function in rats following acute occlusion of the left anterior descending coronary artery (LAD) by using two-dimensional speckle tracking imaging (2D-STI). Sixty Wistar rats were randomly divided into two groups, a myocardial infarction (MI) group, in which 50 rats were subjected to LAD occlusion for 30-45 min, and a sham-operated (SHAM) group that contained 10 rats serving as control. Echocardiography was performed at baseline and 1, 4 and 8 week(s) after the operation. High frequency two-dimensional images of left ventricular short axis at papillary muscle level were recorded. Peak systolic radial strain (PRS) and circumferential strain (PCS) were measured in the mid-ventricle in short-axis view by using EchoPAC workstation. Left ventricular internal diameter at diastole (LVIDd) and systole (LVIDs), fractional shortening (FS), ejection fraction (EF) and left ventricular mass (LVM) were measured by anatomical M-model echocardiography. Infarct size was measured using triphenyl tetrazolium chloride (TTC) staining 1 week and 8 weeks after the operation. Fibrosis of left ventricular myocardium was displayed using Van Gieson staining 1 week after the infarction. In terms of the TTC staining results, the left ventricle fell into three categories: infarcted, peri-infarcted and remote myocardial regions. Compared with those at baseline and in the SHAM group, (1) PRS and PCS in the infarcted, peri-infarcted and remote myocardial regions were significantly decreased in the MI group within 1 week after the operation (P0.05). However, LVIDd, LVIDs and LVM were increased significantly 4 and 8 weeks after the operation (P<0.05), and FS and EF were decreased substantially (P<0.05). Van Gieson staining showed that fibrosis developed in all the three myocardial regions to varying degrees. It is concluded that 2D-STI is non-invasive and can be used to assess regional function of myocardium with different blood supply in rats following acute occlusion of the LAD, and can be used as a sensitive and reliable means to follow up the process of left ventricular remodeling.

Quantitative analysis of myocaridal perfusion in rabbits by tansthoracic real-time myocardial contrast echocardiography / 华中科技大学学报（医学）（英德文版）

To evaluate the feasibility of real-time myocardial contrast echocardiography (RTMCE) by quantitative analysis of myocardial perfusion in rabbits, transthoracic RTMCE was performed in 10 healthy rabbits by using continuous infusion of SonoVue into the auricular vein. The short axis view at the papillary muscle level was obtained. The duration of the time that the contrast took to appear in right heart, left heart and myocardium was recorded. The regional myocardial signal intensity (SI) versus refilling time plots were fitted to an exponential function: y(t) =A(1-e(-beta(t-t0))) + C, where y is SI at any given time, A is the SI plateau that reflects myocardial blood volume, and beta is the slope of the refilling curve that reflects myocardial microbubble velocity. The A, beta and Axbeta values at different infusion rate of SonoVue were analyzed and the A, beta and Axbeta values in each segment in the short axis view at the papillary muscle level were compared. All the animal experiments were successful and high-quality images were obtained. The best intravenous infusion rate for SonoVue was 30 mL/h. The contrast appeared in right heart, left heart and myocardium at 7.5+/-2.2 s, 9.1+/-2.4 s and 12.2+/-1.6 s respectively. After 16.6+/-2.3s, myocardial opacification reached a steady state. The mean A, beta and Axbeta value in the short axis view at the papillary muscle level were 9.8+/-3.0 dB, 1.4+/-0.5 s(-1) and 13.5+/-3.6 dBxs(-1) respectively. A, beta and Axbeta values showed no significant differences among 6 segments. It was suggested that RTMCE was feasible for quantitative analysis of myocardial perfusion in rabbits. It provides a non-invasive method to evaluate the myocardial perfusion in rabbit disease models.

Evaluation of left ventricular torsion in systolic phase in healthy infants, children and adolescents with two-dimensional ultrasound speckle tracking imaging / 中国医学影像技术

Objective To evaluate left ventricular torsion (LVtor) and twist of different segments in systolic phase of healthy infants, children and adolescents with two-dimensional ultrasound speckle tracking imaging (STI). Methods One hundred and seventeen healthy subjects aged from 3 days to 15 years were divided into 5 groups: infants (3 days-2 years), pre-school age children (3-5 years), school age children (6-9 years), preadolescent (10-12 years) and adolescent age (13-15 years). Basal and apical short-axis images of left ventricle were acquired to analyze torsion of every segment and LV torsion. The peak twist (Ptw) of left ventricular was calculated, and the values of different groups were compared. Results ①Seen from the apex level, the normal LV performed wringing motion with clockwise rotation at the base and counterclockwise rotation at the apex in infants, children and adolescents. ②Seen from the short-axis basal level, torsion angle was the biggest in inferior, but the smallest in anterior in same age group (P<0.05). In different age group, there was no statistical difference in torsion angle at basal level. ③Torsion angle of short axis apex level increased with age increasing, and reached peak in adolescents. No statistical difference was found in torsion angle of every segments in apical level among subjects in the same age group. ④Torsion angle of every segment in apical and basal level changed with age increased while ventricular wall rotating mainly with apical plane gradually. In adolescents, significant difference was found in torsion angle in same segments between basal and apical plane (P<0.01). ⑤Torsion of the basal plane of left ventricular changed with age increasing, but no statistical difference was found. Torsion of the apical plane of left ventricular increased with age increasing (P<0.05). Ptw of left ventricular increased with age increasing, and reached the peak in preadolescence and adolescence. ⑥No statistical difference was found in all parameters of torsion and rotation between males and females. Conclusion LVtor in every segment in apical plane and Ptw of left ventricular increase with age increasing before adolescence.

Evaluation of coronary collateral circulation after acute coronary artery occlusion with contrast real-time three-dimensional echocardiography in dogs / 中国医学影像技术

Objective To evaluate the collateral circulation after canine acute coronary artery occlusion with contrast real-time three-dimensional echocardiography (RT-3DE). Methods Left anterior descending coronary artery was ligated in 12 healthy mongrel dogs. All dogs underwent myocardial contrast echocardiography (MCE) before ligation, immediately after ligation, at 30 min and 180 min after ligation respectively, and myocardial mass with collateral supply was calculated. Results Different degrees of collateral circulation were established in all dogs after left anterior descending coronary artery ligation. At 30 min after ligation, the myocardial mass with collateral supply was (9.65±2.90) g, while at 180 min after ligation were (12.58±3.98) g (P<0.01). Conclusion The coronary collateral circulation can be observed clearly and myocardial mass with collateral supply can be quantified accurately with contrast RT-3DE.

Assessment of left ventricular regional myocardial function after acute occlusion of the left anterior descending artery in rats model by two-dimensional strain echocardiography / 中华超声影像学杂志

Objective To explore the value of two-dimensional strain echocardiography for quantitative assessing the change of regional left ventricular myocardial function in rats following acute myocardial infarction. Methods Sixty Wistar rats were randomly divided into two groups. The study group consisted of 50 rats with occlusion of LAD for 30-45 minutes and the sham-operated group consisted of 10 rats without occlusion of LAD. Echocardiography were performed before operation, which was defined as baseline, and 1 week, 4 weeks and 8 weeks after operation. Left ventricular internal diameter at diastole ( LVIDd) and systole < LVIDs), fractional shortening( FS), ejection fraction (EF) and left ventricular mass(LVM) were measured by anatomical M-model echocardiography. High frame rate two-dimensional images were recorded in the left ventricular short-axis views at the papillary muscle level. Peak systolic radial strain(PRS) and circumferential strain(PCS) of each segment were measured using 2-dimensional strain software. The rats were sacrificed and the infarcted size of each segment was measured using triphenyl tetrazolium chloride (TTC) after echocardiography was performed. Fibrosis of left ventricular myocardium was displayed using Van Gieson stain in 1 weeks after infarction. Results Based on the TTC findings,the left ventricle of the study group was divided into three regions:infarcted,peri-infarct and remote myocardial regions. Van Gieson stain showed fibrosis existed in all the three regions. Compared with baseline and sham-operated group, PRS and PCS of infarcted, peri-infarct and remote myocardial regions of the study group significantly decreased within 1 week after operation ( P <0. 01) and persisted for 8 weeks. PCS and PRS of infarcted, peri-infarct and remote myocardial regions of the study group in 4 weeks and 8 weeks after operation showed no significant difference when compared with those in 1 week after operation ( P >0. 01). Compared with baseline and sham-operated group,LVIDd,LVIDs and LVM of study group all increased significantly ( P <0. 05) in 4 weeks and 8 weeks after operation,and FS and EF reduced significantly ( P <0. 05). Two-dimensional strain obtained in interobserver and intraobserver both showed high agreement. Conclusions Two-dimensional strain echocardiography can assess regional function of myocardium with different perfusion in rats following acute myocardial infarction, and provides a sensitive and reliable method to follow up the process of left ventricular remodeling after myocardial infarction.