Objective To evaluate regional myocardial mechanical dysfunction of left ventricle in patients with ECG T-wave inversion using echocardiographic velocity vector imaging.Methods One hundred nineteen female patients with T wave inversion divided into three groups:V1-6 T-wave inversion group(52 patients),V1-4 Twave inversion group (33 patients),V3-6 T-wave inversion group (34patients),while selected 44 healthy women in control group.Peak systolic radial strain (SRSmax) and strain rate (SRSrmax),peak systolic circumferential strain (SCSrmax) and strain rate (SCSmax) were derived and compared from three short-axis views of left ventricle at 18 wall segments using a dedicated Syngo VVI software and workstation,and the depth of T-wave inversion in different precordial lead was measured and correlated with mechanics parameters between four groups.Results In V1-6 T-wave inversion group,each mechanical variable of anteroseptal,anterior,anterolateral and inferolateral walls decreased (P ＜0.05-0.01).In V1-4 T-wave inversion group each mechanical variable of anteroseptal,anterior and inferoseptal walls declined (P ＜0.05-0.01).In V3-6 T-wave inversion group four mechanical variables(i.e.,SRSmax SRSr SCSmax and SCSrmax) of anteroseptal,anterior,anterolateral and inferolateral walls reduced,mainly at basal segment (P ＜0.05-0.01).The ventricular segments of reduced SRSmax,SRSrmax and SCSrmax in V1-6 T-wave inversion group and of SRSrmax in V3-6 T-wave inversion group were more than those in V1-4 T-wave inversion group (P ＜0.05-0.01).In V1-6 T-wave inversion group,negative correlationships between radial mechanical variables of anteroseptal wall and the depths of V4 and V5 lead T-wave inversion were found (r =-0.29--0.37,P ＜0.05-0.01).Otherwise a positive correlationships between SCSmax of anterolateral wall and the depth of V3 lead T-wave inversion were established (rs =0.44,P =0.01) in V1-4 T-wave inversion group.Conclusions There is a regional myocardial dysfunction of LV in female patients with ECG T-wave inversion.The extent of electrical repolarization abnormality is correlated to the severity of regional myocardial dysfunction.

Objective To develop an in vivo procedure f or His bundle pacing (HBP) and radio-frequency (RF) ablation of the atrio-ventricular node (AVN) guided by intracardiac echocardiography (ICE) and tissue Doppler imaging (TDI). The procedure included a custom designed bipolar active fixation pacing lead and steerable delivery catheter, and a commercial RF generator and ablation catheter. Methods Six anesthetized- closed-chest canines were tested. The anatomy in the His bundle and AVN regions, and the onset of myocardial electro-mechanical activation were identified using ICE and TDI. The lead and RF ablation catheter were navigated using an ICE catheter (for local detailed imaging) and fluoroscopy (for global imaging). Surface QRS morphologies were recorded to confirm HBP and third degree block post-ablation. Results Direct His bundle pacing was achieved in one canine, and His + ventricular septal pacing in the remaining five. QRS width in sinus rhythm and HBP were ( 59.7-? 5.3-)ms and ( 82.8-? 16.6-)ms separately (P= 0.02-). The increased QRS width for HBP was due to early septal activation. HBP thresholds were ( 3.0-? 1.0-) volts at 0.5 ms (N=5 due to a late exit block). The mean procedure durations were: HBP 40 minutes (3 to 81 minutes), AVN ablation 3 minutes (2 to 5 minutes), and total X-ray exposure 13 minutes (1 to 55 minutes). Post-mortem analysis of the lead and ablation lesions confirmed correct anatomic localization for HBP and AVN ablation. Conclusions ICE provides precise anatomic guidance of HBP lead implantation and AVN ablation and can significantly reduce exposure to fluoroscopy.

Objective To detect stunned myocardium using low-dose dobutamine stress (DBS)combined with two-dimensional speckle tracking imaging (2D-STI),and to evaluate the difference and characteristics of mechanical parameters in different conditions between stunned myocardium and adjacent normal myocardium.Methods The acute myocardium ischemia/reperfusion (I/R) of anterior wall of left ventricle(LV) was induced with 60 minutes ligation of left anterior descending coronary artery (LAD),and with reperfusion of 120 minutes in 10 open-chest beagle dogs.Dobutamine was administered continuously via vein with two different dose of 5 μg · kg-1 · min-1 and 10 μg · kg-1 · min-1.At baseline,post ischemia/reperfusion,after the first DBS and the second,the gray-scale dynamic images of three cardiac cycle of left ventricular short axis at the levels of mitral annulus,papillary muscle and apex were acquired.The systolic peak of circumferential strain (CS),radial displacement (RD) of eighteen segments of subendocardium and subepicardium were analyzed by Speckle tracking workstation.LV end-systolic dimension(LVIDS),LV end-diastolic dimension (LVIDD),LV eject fraction (LVEF),heart rate (HR),aortic valve forward flow velocity time integral(AV-VTI) were also measured.Results ①There was no statistical significance (P ＞0.05) under the conditions of baseline,post I/R,the first DBS and the second for LVIDD,LVIDS,LVEF,HR and AV-VTI.②Compared with baseline,the peak systolic subendocardium and subepicardium CS,RD decreased significantly at the apex and middle of short-axis anterior wall of LV under the conditions of post I/R;The parameters of the first DBS was significantly increased compared with the I/R (P ＜ 0.05) ; There was no difference between the two DBS and baseline(P ＞0.05).The peak systolic subendocardium and subepicardium CS,RD at the bottom segment of LV were no statistical significance under the four conditions.③There was no difference for anterolateral wall and anterior septum of LV at the level of papillary muscle under the four conditions.Conclusions ①Low-dose DBS combined with two-dimensional speckle tracking imaging can detect stunned myocardium accurately.② After the occurrence stunning myoeardium,the peak systolic subendocardium RD decreased slightly,subepicardium RD was normal,the subendocardium CS of the surrounding myocardium was still normal,and the peak systolic subepicardium CS decreased to some degree.

BACKGROUND:Acute myocardial infarction with acute onset is dangerous, but the aided diagnosis for hyperacute disease mainly depends on electrocardiogram. The advantages of tissue Doppler strain imaging were utilized to help early diagnosis of acute myocardial infarction.
OBJECTIVE:To observe left ventricular transmural peak radial strain and strain time-to-peak of subendocardiac muscle, midmyocardium and subepicardiac muscle using tissue Doppler strain imaging in dogs before and after acute myocardial infarction, and to assess its mechanical characteristics.
METHODS:A total of 16 Beagle dog models of acute myocardial ischemia were established by ligating left anterior descending coronary artery. The two-dimensional apical short-axis views of the left ventricle in five complete cardiac cycles were acquired and stored in TDI-Q workstation before and after acute myocardial ischemia. Transmural peak radial strain and strain time-to-peak of segment, subendocardiac muscle, midmyocardium and subepicardiac muscle at infarct region and baseline were observed.
RESULTS AND CONCLUSION:Peak radial strains at infarct and subendocardiac muscle, midmyocardium and subepicardiac muscle were decreased compared with the baseline (P<0.05). Peak strain gradient disappeared in each layer of infarct myocardium. Strain time-to-peak of the whole segment and infarct myocardium at different layers was significantly postponed (P<0.05). There was a positive correlation of peak radial strain between subendocardium and segment as wel as between medium and segment at baseline (r=0.617, P<0.01;r=0.556, P<0.01). This relationship disappeared at infarct region (r=0.338, P>0.05;r=0.218, P>0.05). Results indicated that after acute myocardial infarction, peak strain gradient disappeared at different layers at infarct region. Acute myocardial ischemia induces peak radial strain decrease at subendocardium, medium, subepicardium and strain time-to-peak at infarct region was significantly postponed, which reflected abnormal cardiac structure and dysfunction, resulted in uncoordinated cardiac motion and asynchronous heart movement. This may be an important mechanical mechanism triggering heart failure.

Objective To investigate the effects of miR-335-5p on the proliferation and apoptosis of osteoblasts which were exposed to high glucose condition, and explore its possible molecular mechanisms. Methods MC3T3-E1 osteoblasts were divided into four groups:control group(5. 5 mmol/L glucose), high glucose group(HG group, 22. 0 mmol/L glucose), agomir-335-5p group(transfected with agomir-335-5p and exposed to 22. 0 mmol/L glucose) , and agomir negative control group( agomir NC group, transfected with agomir negative control and exposed to 22. 0 mmol/L glucose), cultured for 7 days. Cell proliferaton, cell apoptosis, expressions of miR-335-5p and dickkopfhomolog1(DKK1)mRNA,proteinlevelsofDKK1andcysteinylaspartate-specificproteinase-3(caspase-3) were detected using MTT, flow cytometry, quantitative realtime PCR and western blot, respectively. Results Compared with control group, the expression of miR-335-5p mRNA and cell proliferation in HG group were significantly decreased(P<0. 05), while cell apoptosis and the protein levels of DKK1 and caspase-3 were increased significantly(P<0. 05), the expression of DKK1 mRNA did not change (P>0. 05). The miR-335-5p mRNA expression and cell proliferation in agomir-335-5p group were higher than those in HG group and agomir NC group(P<0. 05). However, Cell apoptosis and the protein levels of DKK1 and caspase-3 in agomir-335-5p group were lower than those in HG group(P<0. 05). Conclusion High glucose inhibits the proliferation and induce the apoptosis of MC3T3-E1 osteoblast through decreasing the expression of miR-335-5p and subsequently increasing the DKK1 expression.

Objective To assess longitudinal segmental myocardial strain(?),displacement(D) and the changes of the inner dimension of left ventricle(?L),and to establish their spatial correlationship during cardiac pacing and conductive block.Methods The standard apical four chamber view of left ventricle were acquired during cardiac pacing(n=12),right bundle branch block(RBBB,n=13) and sinus rhythm(n=14) using GE Vivid 7 dimension and the M3S probe with(4.0) MHz for the analysis of the longitudinal myocardial segmental(apical and basal segments) ? and D of left ventricle with two dimensional strain analysis software.The maximal and change longitudinal dimension of left ventricle was measured and calculated at end-diastole and end-systole respectively.The differences of the above parameters were compared and the spatial correlationships among them were analyzed.Results The peak ? of the septal basal segment during cardiac pacing was significant higher than that of the apical segment.There were significant differences in the peak D and(?D)(D_(basal)-D_(apical)) at lateral wall among sinus rhythm,RBBB and pacing group(P

OBJECTIVE To investigate the prevalence of erythromycin resistance genes ermB and mefA and the relationship of drug resistance and genes in Streptococcus pneumoniae.METHODS Forty three strains of S. pneumoniae were collected from respiratory system infected children from Dec 2004 to Oct 2005 at Yuying Pediatric Hospital of Wenzhou Medical College.Erythromycin sensitivity test was done by using MIC method.The erythromycin resistance genes ermB and mefA were detected by PCR.RESULTS In all forty three strains,forty were erythromycin resistant(93%),three were erythromycin sensitive.The total detection rate of erythromycin resistance genes ermB and mefA was 76.7% and 23.3%,respectively.There were neither gene ermB nor gene mefA in 3 erythromycin-sensitive S.pneumoniae.In 40 strains the detection rate of gene ermB was 82.5% and that of gene mefA was 25%.The erythromycin resistance gene ermB or mefA were detected in 35 of the 43 strains.The total detection rate of erythromycin resistance gene was 81.4%.In the 35 erythromycin resistance strains there were 25 strains in which gene ermB existed lonely and 2 strains in which gene mefA existed lonely.There were both genes ermB and gene mefA in 8 of the 35 erythromycin resistance strains.CONCLUSIONS The erythromycin resistance of S.pneumoniae can be caused mainly by gene expression of ermB or mefA,but the gene mefA seems to be less important than gene ermB.Obviously the erythromycin isn′t useful in treating S.pneumoniae infection.

Objective To investigate the relationship between family function and unhealthy mood in patients with vascular dementia (VD).Methods 120 VD patients were investigated by the Family APGAR index (APGAR),Hamilton Depression Scale (HAMD),Hamilton Anxiety Scale (HAMA),and Mini-Mental State Examination (MMSE).Results 98 cases (81.7％) were in depression with anxiety.Family dysfunction was presented in 83.3％ of 120 VD patients.The mild and moderate cognitive impairment were present in 55.8％ and 44.2％.The score of MMSE,the total score and factors scores of APGA were negatively related to the score of HAMD and HAMA.The score of MMSE was positively related to the total score and factors scores of APGA.The family dysfunction,self-reported financial burden and cognitive disorder were the risk factors of unhealthy mood (OR＞1).Conclusions The results suggest that improvement of VD patients' family function,reducing the economic burden and enhancing cognitive function can possibly relieve the unhealthy mood of patients.

ObjectiveTo investigate the molecular response of adult and neonate ovine articular cartilage to acute mechanical injury.MethodsAn established in vitro model was used to compare gene expression difference of ovine articular cartilage explants at different developmental stages 24 hours after mechanical injury and the gene expression was compared between these models and that of the uninjured controls by microarray analysis.Total RNA was isolated from the tissue samples,linearly amplified,and applied to a 15 208 Ovine probes cDNA microarray(Agilent).Validation for selected genes(PPARγ,GRO TNC and LDHA) was obtained by real-time polymerase chain reaction.Comparisons between groups were performed by variance analysis.ResultsThere was significant difference in gene expression in adult and neonatal ovine articular cartilage after mechanical injury.Eighty-six genes were significantly manipulated at least 2-fold following mechanical injury for neonate sheep and 83 genes for adult sheep (P＜0.05).Conclusion Our findings indicate that mechanical injury to adult and neonatal ovine articular cartilage results in the activation of a series of signaling responses.We could identify four significant genes that are up or downregulated in response to acute mechanical injury.Significant functional clusters including genes associated with wound healing,articular protection,repair integration,and energy metabolism.Of these,PPARG could be specifically identified as novel target molecules and potential chondroprotective agent involved in traumatic cartilage injury and cartilage integrated repair.

Objective To observe left ventricular transmural peak radial strain and strain time-to-peak of peri-infarct different layers myocardium using tissue Doppler strain imaging, to assess its mechanical pattern during acute myocardial ischemia.Methods Left anterior descending coronary artery (LAD) were ligated in experimental open-chest Beagle dog models (n = 9),the two-dimensional apical short-axis views of left ventricle in three complete cardiac cycles were acquired and stored in TDI-Q workstation at baseline(the control group of peri-infarc myocardium) and during acute myocardial ischemia respectively.Sampling volume was uesd to measure the peak radial strain and the strain time-to-peak consesquently on the derived M -mode tissue Doppler velocity images at peri-infarct myocardium before and after ischemic segments and different layers(subendocardium, medium, subepicardium).Statistical analies was performed using student's t- test or Pearson's correlations.Results Peak radial strain decreased at peri-infarct subendoeardium (P<0.05) with no significant difference between those at baseline and at peri-infarct medium (P >0.05), the peak radial strain increasd at peri-infarct subepieardium (P < 0.05) ,and the strain time-to-peak at different layers of peri-infarct myoeardium was significantly postponed (P< 0.05).There was a good correlationship of peak radial strain between subendocardium and segment as well as between the medium and segment (r = 0.617, P<0.01 ; r = 0.556, P<0.01).This correlationship disappeared at peri-infarct myocardial segment (r = 0.287, P > 0.05, r = 0.243, P > 0.05).Conclusions The left ventricular transmural mechanical remodeling at peri-infarct myocardium is the integrant of result of mechanical interactions between ischemic and nonischemic myocardium,which might be one of the trigger the structural and fundational remodeling processes involving in the pathophysiological foundation of ischemie cardiomyopathy.