ABSTRACT
Objective To assess longitudinal segmental myocardial strain and displacement of left ventricle (LV) in patients with dual chamber pacing (DDD) using velocity vector imaging (VVI) and to explore the clinical application value of VVI in assessing left ventricular motion.Methods A total of 23 patients before and after DDD pacemaker implantation were enrolled in this study.The peak systolic strain and displacement of ventricular segments were measured with VVI and compared before and after pacemaker implantation.Results Compared to the values at the baseline,the strain and displacement of lateral,interventricular septum,anterior and posterior wall of LV in patients with pacing were significantly decreased.The strain,displacement of basal and mid segments with pacing were decreased as well(P＜0.01).The left ventricular strain and displacement in patients with pacing were significantly decreased than those of patients at the baseline(P＜0.05).Left ventricular longitudinal displacement before and after DDD pacing was significantly decreased from basal,mid to apical segments.But no significant difference was found in longitudinal strain from basal,mid to apical segments of LV.Conclusions (1) Left ventricular strain and displacement in patients with pacing were different between those before and after DDD pacing.(2) VVI can accurately assess left ventricular strain and displacement in patients with DDD pacing,and can become a powerful mean to assess the regional myocardial function.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the inhibitory effect of tyroservatide (YSV) on growth of hepatocellular carcinoma cells.</p><p><b>METHODS</b>In vitro effects of YSV on five human hepatocellular carcinoma cell lines were assayed by MTS. In vivo effects of YSV on 5 human hepatocellular carcinoma cell lines were assayed by hollow fiber tumor model.</p><p><b>RESULTS</b>After treatment with YSV at a dose of 0.1 approximately 1.6 mg/ml, the growth of the five cell lines was significantly inhibited in vitro compared with that of the control group (P < 0.05). Especially, YSL remarkably inhibited the growth of human hepatocellular carcinoma BEL-7402 cells, i.e. the cell growth was inhibited by 63.3% after treatment with YSL at 1.6 mg/ml. The hollow fiber tumor model demonstrated that YSL (320 microg x kg(-1) x d(-1) and 640 microg x kg(-1) x d(-1)) treatment significantly inhibited the in vivo growth of the five cancer cell lines compared with that in the saline control (P < 0.05). YSL showed the highest level of inhibition of human BEL-7402 hepatocellular carcinoma cells, with an inhibitory index of 53.1% at 320 microg x kg(-1) x d(-1).</p><p><b>CONCLUSION</b>As a new method, hollow fiber assay may be used to evaluate the inhibitory effect of drugs on different tumor cells in vivo, rapidly, accurately and economically. Our results provide an instruction and evidence for clinical use of YSV.</p>