1.Mechanisms of tumor necrosis factor-related apoptosis inducing ligandcombined with Triptolide in inducing the apoptosis of pancreatic cancer cells
Yan JIANG ; Wei LIU ; Zhiyu CHEN
Chinese Journal of Digestive Surgery 2015;14(4):321-328
Objective To investigate the mechanisms of tumor necrosis factor-related apoptosis inducing ligand (TRAIL) combined with Triptolide in inducing the apoptosis of pancreatic cancer cells.Methods (1) The pancreatic cancer cells (MiaPaca-2 cells) were divided into 4 groups:blank control group (no drugs were added),TRAIL + Triptolide-group (only TRAIL was added),TRAIL-Triptolide + group (only Triptolide was added) and TRAIL+ Triptolide+ group (TRAIL and Triptolide were added).The vitality of cells in all the 4 groups was assessed by CCK-8.The expressions of poly ADP-ribose polymerase (PARP),cysteinyl aspartate specific proteinase-3 (Caspase-3) and Caspase-8 were detected by Western blot.The vitality of cells was detected by CCK-8 and the vitality of Caspase-8 was detected by Caspase-Glo assays after adding Z-IETD-FMK,a specific inhibitor of Caspase-8.The expressions of myeloid cell leukemia-1 (Mcl-1),Bcl-xL and Bcl-2 were detected by Western blot.(2) The MiaPaca-2 cells were divided into 8 groups:①TRAIL-Mcl-1 siRNA-group (no TRAIL was added and Mcl-1 siRNA cells were not transfected),TRAIL+ Mcl-1 siRNA-group (TRAIL was added and Mcl-1 siRNA cells were not transfected),TRAIL-Mcl-1 siRNA + group (TRAIL was not added and Mcl-1 siRNA cells were transfected)and TRAIL+ Mcl-1 siRNA+ group (TRAIL was added and Mcl-1 siRNA cells were transfected).②TRAIL-Bcl-xL siRNA-group (TRAIL was not added and Bcl-xL siRNA was not transfected),TRAIL+ Bcl-xL siRNA-group (TRAIL was added and Bcl-xL siRNA was not transfected),TRAIL-Bcl-xL siRNA + group (TRAIL was not added and Bcl-xL siRNA was transfected) and TRAIL+ Bcl-xL siRNA+ group (TRAIL was added and Bcl-xL siRNA was transfected).The vitality of the cells in all the groups was detected by CCK-8.The expressions of Caspase-3 and Caspase-8 protein were detected by Western blot.The measurement data with normal distribution were presented as (x) ± s.The comparison among groups was done by ANOVA,and the pairwise comparison was done by LSD-t test.Results (1) The vitalities of MiaPaca-2 cells in the blank control group,TRAIL + Triptolide-group,TRAIL-Triptolide + group and TRAIL + Triptolide + group were 100.0% ± 1.1%,81.2% ± 2.3%,78.6% ± 3.6%and 40.1% ± 2.5 %,and the relative expressions of PARP protein were 0.510 ± 0.028,0.720 ±0.072,1.250 ±0.023 and 2.560 ± 0.220,the relative expressions of Caspase-3 were 0.080 ± 0.004,0.080 ± 0.003,0.110 ±0.005 and 2.720 ± 0.003,and the relative expressions of Caspase-8 were 0.070 ± 0.003,0.080 ± 0.005,0.120 ±0.003 and 0.990 ± 0.006,with significant differences among the 4 groups (F =203.607,1 457.785,332 421.900,35 437.218,P < 0.05).The vitality of M iaPaca-2 cells in the TRAIL + Triptolide + group was significantly different from those in the blank control group,the TRAIL + Triptolide-group and the TRAIL-Triptolide + group (t =34.583,355.936,36.271,P < 0.05).The relative expression of PARP protein of MiaPaca-2 cells in the TRAIL+ Triptolide + group was significantly different from those in the blank control group,TRAIL+ Triptolidegroup and TRAIL-Triptolide + group (t =591.784,63.739,2 268.987,P < 0.05).The relative expression of Caspase-3 protein of the MiaPaca-2 cells in the TRAIL + Triptolide + group was significantly different from those in the blank control group,the TRAIL + Triptolide-group and theTRAIL-Triptolide + group (t =3 266.153,9 145.228,1 738.713,P <0.05).The relative expression of Caspase-8 protein of the MiaPaca-2 cells in the TRAIL+ Triptolide +group was significantly different from those in the blank control group,the TRAIL+ Triptolide-group and the TRAIL-Triptolide + group (t =663.953,l 432.878,327.584,P < 0.05).The vitality of caspase-8 in the TRAIL+ Triptolide+ group was 711.0% ± 5.1% before adding Z-IETD-FMK,and then the vitality of MiaPaca-2 cells and caspase-8 changed to 70.0% ± 4.8% and 73.0% ± 2.4%,with significant differences (t =17.956,55.027,P < 0.05).The relative expressions of Mcl-1 protein in the blank control group,the TRAIL + Triptolidegroup,the TRAIL Triptolide + group and the TRAIL + Triptolide + group were 1.68 ± 0.22,2.08 ± 0.11,0.73 ±0.15 and 0.58 ± 0.18,the relative expressions of Bcl-xL protein were 0.65 ± 0.03,0.47 ± 0.03,0.32 ± 0.03and 0.26 ±0.05,the relative expressions of Bcl-2 protein were 0.65 ± 0.03,0.67 ± 0.03,0.62 ± 0.05 and 0.67 ± 0.03,with significant difference among the 4 groups (F =55.178,88.683,3.411,P < 0.05).The relative expressions of Mcl-1 protein of the MiaPaca-2 cells in the TRAIL-Triptolide + group and the TRAIL+ Triptolide +group were significantly different from those of the blank control group (t =23.506,47.631,P < 0.05) and the TRAIL + Triptolide-group (t =58.457,37.115,P < 0.05).The relative expressions of Bcl-xL protein of the MiaPaca-2 cells in the TRAIL-Triptolide + group and the TRAIL + Triptolide + group were significantly different from those of the blank control group (t =38.105,42.219,P < 0.05) and the TRAIL + Triptolide-group (t =32.476,15.814,P < 0.05).The relative expressions of Bcl-2 protein in the TRAIL-Triptolide + group and the TRAIL+ Triptolide + group were not significantly different from those of the blank control group (t =4.724,1.732,P > 0.05) and the TRAIL + Triptolide-group (t =3.464,0.000,P > 0.05).(2) The vitalities of MiaPaca-2 cells of the TRAIL-Mcl-1 siRNA-group,TRAIL + Mcl-1 siRNA-group,the TRAIL-Mcl-1 siRNA + group and the TRAIL + Mcl-1 siRNA + group were 100.0% ± 2.2%,79.3% ± 1.8%,71.2% ± 3.2% and 37.3% ± 5.4%,the relative expressions of Caspase-8 protein were 0.100 ± 0.003,0.100 ± 0.005,0.100 ± 0.003 and 0.350 ±0.005,and the relative expressions of Caspase-3 protein were 0.020 ± 0.003,0.060 ± 0.003,0.020 ± 0.003 and 0.590 ±0.004,with significant differences among the 4 groups (F =136.681,2 717.391,44 471.429,P <0.05).The vitality of MiaPaca-2 cells of the TRAIL + Mcl-1 siRNA + group was significantly different from those in the TRAIL-Mcl-1 siRNA-group,the TRAIL + Mcl-1 siRNA-group and the TRAIL-Mcl-1 siRNA + group (t =33.937,20.207,26.689,P < 0.05).The relative expression of Caspase-8 protein of the TRAIL + Mcl-1 siRNA +group was significantly different from those in the TRAIL-Mcl-1 siRNA-group,the TRAIL + Mcl-1 siRNA-group and the TRAIL-Mcl-1 siRNA + group (t =216.506,433.013,144.338,P < 0.05).The relative expression of Caspase-3 protein of the TRAIL + Mcl-1 siRNA + group was significantly different from those in the TRAIL-Mcl-1 siRNA-group,the TRAIL + Mcl-1 siRNA-group and the TRAIL-Mcl-1 siRNA + group (t =329.09,458.993,987.269,P <0.05).The vitalities of MiaPaca-2 cells of the TRAIL-Bcl-xL siRNA-group,the TRAIL+ Bcl-xL siRNA-group,the TRAIL-Bcl-xL siRNA + group and the TRAIL+ Bcl-xL siRNA + group were 100.0% ± 2.3%,87.2% ± 4.1%,74.1 ± 3.7% and 56.3% ± 5.4%,and the relative expressions of Caspase-3 protein were 0.060 ±0.004,0.070 ± 0.003,0.060 ± 0.004 and 0.390 ± 0.003,with significant differences among the 4 groups (F =70.074,4 643.478,P < 0.05).The vitality of MiaPaca-2 cells of the TRAIL + Bcl-xL siRNA + group was significantly different from those in the TRAIL-Bcl-xL siRNA-group,the TRAIL+ Bcl-xL siRNA-group and the TRAIL-Bcl-xL siRNA + group (t =24.416,41.170,18.136,P < 0.05).The relative expression of Caspase-3 protein of the TRAIL + Bcl-xL siRNA + group was significantly different from those in the TRAIL-Mcl-1 siRNA-group,the TRAIL + Mcl-1 siRNA-group and the TRAIL-Mcl-1 siRNA + group (t =285.788,554.256,190.526,P < 0.05).Conclusion Triptolide could induce the apoptosis of MiaPaca-2 cells by inhibiting the expressions of Mcl-1 and Bcl-xL,sensitizing TRAIL and activating Caspase-8 and Caspase-3.
2.Diagnosis and treatment of the sphenoid sinus malignant tumor
Xing YE ; Zhiyu YAN ; Guangliang GUO ;
Chinese Archives of Otolaryngology-Head and Neck Surgery 2006;0(09):-
OBJECTIVE To investigate the clinical characteristics,nasal endoscope and imaging findings, misdiagnosis and treatment results of sphenoid sinus malignant tumor.METHODS The clinical data of 9 cases with sphenoid sinus malignant tumor were summarized and analyzed.Headache was found in 8 patients, ophthalmic symptoms in 3 patients,nasal bleeding and obstruction in 3 patients,and cranial nerve palsy in 2 patients.They were often misdiagnosed as sphenoid sinusitis and nasopharyngeal carcinoma.RESULTS Only 1 patient with papillary carcinoma was cured for 6 years.One patient with neuroendocrine carcinoma was alive for 3 years after treatment.Four patients died at 2 to 3 years.Two patients were alive at 1 year after operation. One patient was lost to follow up.CONCLUSION Sphenoid sinus tumor had no characteristic symptoms in early stage.It is easy to misdiagnose and delay diagnosis. Patients with headache,visual symptoms and nasal bleeding should take nasal endoscopy,CT scan and MRI examination at early stage.
3.Insulin-like growth factor 1 promotes in vitro proliferation of chondrocytes in traumatic arthritis
Guang ZHAO ; Jifeng JING ; Zhiyu ZHANG ; Jiajun ZHU ; Yan CUI
Chinese Journal of Tissue Engineering Research 2014;(2):183-186
BACKGROUND:The early damaged chondrocytes are susceptible to de-differentiate and exert unstable phenotype during the in vitro culture, thus needing some growth factors.
OBJECTIVE:To observe the promotion effect of insulin-like growth factor 1 on the in vitro proliferation of chondrocytes in adult rabbits with traumatic arthritis.
METHODS:Traumatic arthritis models of adult rabbits were established by using the modified Hulth method. After the models were successful y established, the distal femur and proximal tibia were harvested under sterile conditions, the chondrocytes were cultured. The cultured cells were divided into two groups:control group was cultured with Dulbecco’s modified Eagle’s medium containing 10%fetal bovine serum, while experimental group was cultured with Dulbecco's modified Eagle’s medium containing 100μg/L insulin-like growth factor 1. The effect of insulin-like growth factor 1 on the proliferation of chondrocytes in adult rabbits with traumatic arthritis was determined through the cytomorphology, cellcounting, and cellactivity.
RESULTS AND CONCLUSION:The chondrocytes in adult rabbits with traumatic arthritis were successful y cultured, the majority of cells were mini-cells, presenting smal fusiform, round or polygonal shape. Hematoxylin-eosin staining showed that the number of cells in experimental group was higher than that in control group. MTT assay found that the absorbance of cells in experimental group was greater than that in control group (P<0.01). Our findings indicate that, insulin-like growth factor 1 can promote the in vitro proliferation of chondrocytes in adult rabbits with traumatic arthritis.
4.Doppler ultrasound screening for deep vein thrombosis in patients with lower limb fracture
Youqing YAN ; Hua REN ; Kun FENG ; Chaohui DU ; Zhiyu WEI
Chinese Journal of General Practitioners 2011;10(9):673-674
One hundred and sixteen patients with lower limb fracture were screened by Doppler ultrasound for deep vein thrombosis(DVT) of bilateral lower extremities within the first 72 h, d7 and d21 after fracture. Results showed that DVT was detected in 31 (26. 7% ) out of 116 cases within 72 h; at d7 and d21 DVT was detected in 3 and 1 patient respectively with a cumulated DVT rate of 30. 2% in 3 weeks.Serial Doppler ultrasonography is of value in screening for DVT of the lower extremities in patients with lower limb fracture at early stage.
5.Three-dimensional printing technology-aided total knee arthroplasty for osteoarthritis with genu varum deformity
Zhenguo SUN ; Jiajun ZHU ; Yan CUI ; Shenghui NI ; Zhiyu ZHANG
Chinese Journal of Tissue Engineering Research 2017;21(15):2395-2399
BACKGROUND: The complicated localization of intramedullary nails and osteotomy more dependent on surgeons' experience limit the application of conventional total knee arthroplasty (TKA). The occurrence of three-dimensional (3D) printing technology can achieve precise localization and osteotomy in TKA.OBJECTIVE: To explore the effectiveness of 3D printing technology-aided TKA versus conventional TKA for genu varum.METHODS: Thirty-four patients with genu varum undergoing primary unilateral TKA were recruited and were then divided into two groups (n=17 per group) in accordance with the random number table. One group was treated with TKA with 3D printing guild plate (3D printing group), while the other group received the conventional TKA (conventional group).The intraoperative and postoperative blood loss, operation time, as well as the Hospital for Special Surgery score, range of motion, and lower limb mechanical alignment at 2 weeks postoperatively were compared between two groups.RESULTS AND CONCLUSION: (1) The range of motion of knee in the 3D printing group was larger than that in the conventional group, but had no significant difference at 2 weeks postoperatively (P=0.744). (2) There was no significant difference in the Hospital for Special Surgery scores between two groups at 2 weeks postoperatively (P= 0.532). (3) The postoperative lower limb mechanical alignment showed no significant difference between two groups (t=0.218, P=0.632).(4) The operation time in the 3D printing group was significantly shorter than that in the conventional group (P=0.000). (5) The blood loss in the 3D printing group was significantly less than that in the conventional group (P=0.000). (6) Our findings indicate that 3D printing technology-aided TKA exhibits similar results to the conventional TKA in the Hospital for Special Surgery scores, range of motion, and lower limb mechanical alignment, but it shortens the operation time,reduces the blood loss, and achieves precise osteotomy, which is available for the elderly with poor basic condition, and weak tolerance of surgery.
6.The impact of polyclonal neural cell adhesion molecule antibody on the potency of botulinum toxin
Yan GUO ; Lingjing JIN ; Wuchao LIU ; Yuguo ZHENG ; Qiang GUAN ; Lizhen PAN ; Zhiyu NIE
Chinese Journal of Physical Medicine and Rehabilitation 2013;35(11):833-838
Objective To investigate the impact of polyclonal neural cell adhesion molecule antibody (P-NCAM-Ab) on the potency of botulinum toxin A (BTX-A).Methods Ninety male Sprague-Dawley rats were randomly divided into 3 equal groups:a normal control group,a BTX-A group and a P-NCAM-Ab group.The rats in the normal control group were injected with 100 μl of saline solution in their right gastrocnemius,while those in the BTX-A and P-NCAM-Ab groups were injected with 100 μl of BTX-A (0.5 U).In addition,the rats in the P-NCAM-Ab group were also injected with 100 μl of P-NCAM-Ab (the dosage was 20 U) at the same site on the 3rd day after the BTX-A injection.The rats' gastrocnemius muscle strength was evaluated with a self-made system for evaluating neuromuscular function before and after the toxin injection,on the 3rd day,as well as 1,2,4,6,8,10 and 12 weeks after the BTX-A injection.Any wet weight changes in the muscles were observed,and immunochemistry methods were employed to observe any structural changes in the motor endplates and nerve fibers at the different time points.Results After the saline injection,the average gastrocnemius muscle strength of the control group increased with time,while strength in the BTX-A and P-NCAM-Ab groups demonstrated a decrease in strength followed by a gradual increase.The average gastrocnemius muscle strength of the rats in the BTX-A and P-NCAM-Ab groups was significantly lower than that of the control group at all time points.Compared with the BTX-A group,the muscle strength of the P-NCAM-Ab group rats decreased further.Strength recovery in the BTX-A and P-NCAM-Ab groups was significantly slower than in the control group.The wet weight percentage in the BTX-A and P-NCAM-Ab groups at first decreased and then recovered with time.After the BTX-A injection,the average wet weight percentage of the P-NCAM-Ab group rats was significantly lower than that of the BTX-A group after 3 days,and 1,2 and 4 weeks.Karnovsky-Roots AchE staining showed that the motor endplates' color in the BTX-A and P-NCAM-Ab groups deepened gradually,though the color of the P-NCAM-Ab group was lighter than that of the BTX-A group at each time point.The mean optical density of the motor endplates' positive reaction area increased with time in both groups,but the P-NCAM-Ab group was lower than that of the BTX-A group at 1,2,4,8 and 12 weeks.Counting the nerve fibers dyed by gold chloride showed similar trends with both experimental groups significantly different from the control group.Conclusion P-NCAM-Ab can increase the potency of BTX-A and prolong its action.
7.Effects of heptanol preconditioning on structure, function and Cx43 content of mitochondria in rabbit model of myocardial ischemia/reperfusion injury
Yan HE ; Guoqiang ZHONG ; Zhiyu ZENG ; Weike LI ; Wei LI ; Jinyi LI
Chinese Journal of Pathophysiology 2010;26(3):461-465
AIM: To investigate the effects of heptanol preconditioning on the changes of structure, function and connexin 43 (Cx43) content in mitochondria in a rabbit model of myocardial isehemia-reperfusion (IR) injury. METHODS: In anesthetized open-chest rabbits, the left anterior descending artery (LAD) was occluded for 30 min and reperfused for 4 h. Sixty-four rabbits were randomly divided into 4 groups (n=16 in each group): sham operation group (sham group), ischemia-reperfusion group (IR group), ischemic preconditioning group (IP group) and heptanol preconditioning group (HT group). All rabbits in the 4 groups were killed 4 h after reperfusion. Myocardial infarct size was determined at the end of the experiment. Mitochondria was isolated by centrifugations. The ultrastructural changes of the mitochondria were observed under electronic microscope. The mitochondrial membrane potential, Ca~(2+) concentration, MDA content and SOD activity of myocardial mitochondria were also examined. The content of mitochondria Cx43 was detected by Western blotting. RESULTS: Compared to IR group, the myocardial infarct size was significantly reduced in IP (18.97%±2.80%) and HT (19.97%±3.80%) groups, the damage of mitoehondrial ultrastructure was milder (P<0.05), mitochondrial membrane potential was significantly higher and Ca~(2+) concentration was much lower (P<0.01) in IP group and HT group. No significant difference of MDA content and SOD activity in myocardial mitochondria between IR group and HT group was found. However, MDA content were much lower and SOD activity was significantly higher in IP group as compared to IR group (P<0.01). Compared to sham group, the mitochondria Cx43 expression was distinctly decreased compared to IR group (P<0.05) and no significant difference was found between IP group and HT group (P>0.05). CONCLUSION: Heptanol preconditioning protects myocardium from ischemia-reperfusion injury. The mechanism may be related to increasing in mitochondrial membrane potential, alleviating Ca~(2+) overload in myocardial mitochondria and attenuating the decrease in mitochondria Cx43 expression induced by isehemia-reperfusion.
8.Cx43 in mitochondria participates in the protection for heptanol preconditioning on myocardial ischemia/reperfusion injury of rabbits
Yan HE ; Zhiyu ZENG ; Guoqiang ZHONG ; Jinyi LI ; Weike LI ; Wei LI
Chinese Pharmacological Bulletin 2009;25(12):1660-1665
Aim To investigate the roles of Cx43 in mitochondria and mitochondrial ATP sensitive potassium channe1(mitoK_(ATP)~+)participating in the protection for heptanol preconditioning on myocardial ischemia/reperfusion injury of rabbits.Methods In anesthetized open-chest rabbits,the left anterior descending artery(LAD)was occluded for 30 min and reperfused for 4 hrs.All rabbits were randomly divided into five groups(n=16 in each group):sham operation group(Group Sham),ischemic reperfusion group(Group IR),ischemic preconditioning group(Group IP),heptanol preconditioning group(Group HT)and 5-HD plus heptanol preconditioning group(Group HT+5-HD),All rabbits in the five groups were killed 4h after reperfusion.Myocardial infarct size was determined at the end of the experiment.The heart rate and the mean arterial pressure(MAP)were recorded and plasma CK-MB and cTnI activity were measured at baseline,the end of ischemia,and after 2 hrs and 4 hrs of reperfusion respectively.Mitochondria was isolated with different centrifugations.Ultrastructural changes of mitochondria were observed under electron microscope.The content of the mitochondria Cx43 was detected with Western blot.Results The plasma CK-MB,cTnI activity and myocardial infarct size were significantly reduced in IP(18.97±2.8)% and HT(19.97±3.8)% groups as compared to IR groups (35.67±5.8)%,(P<0.01).Compared to group IR,the damage of mitochondria in group IP and group HT were milder(P<0.01).No significant difference was found between Group IP and Group HT.Compared to sham group, the mitochondria Cx43 expression was distinctly decreased in group IR and group HT+5-HD(P<0.01)and no significant difference was found between Group IP and Group HT.Conclusions Heptanol preconditioning can protect the heart from I/R injury by improving mitochondrial ultrastructure and by attenuating the decrease of mitochondria Cx43 expression induced by I/R.The mitochondrial Cx43 expression may be concerned with depending on mito K_(ATP)~+.
9.Morphology changes of ocular anterior segment and its influencing factors following LASIK
Jie, WANG ; Zhiyu, DU ; Xueyao, LI ; Yu, ZHANG ; Pisong, YAN ; Huizhen, CHEN ; Hao, YAO
Chinese Journal of Experimental Ophthalmology 2016;34(8):729-733
Background Laser in situ keratomileusis (LASIK) is widely applicated to correct the refractive error in ophthalmology nowadays.However,the morphology and structure changes of anterior eye segment caused by the ablation of corneal stroma and suction of negative pressure during surgery should be concerned.Objective This study was to assess the changes of the anterior eye segment parameters and the factors influencing these parameters after LASIK.Methods The clinical data of 59 eyes of 31 patients who received LASIK in Chongqing Medal Eye Institute during May 2012 to July 2013 were retrospectively analyzed.The mean age of the patients was (24.52±8.41) years and the spherical equivalent was (-5.96±3.75) D.The central anterior chamber angle (ACA),anterior chamber volume (ACV),anterior chamber depth (ACD) were measured with Sirius Scheimpflug tomography,and lens thickness (LT) was measured by A-scan before operation and 1,3,6 months after operation.The anterior chamber was divided into anterior and posterior parts by the plane of cornea 4 mm radius area.The ACD of cornea 4 mm radius area sagittal height section (Sag4mm ACD) (the height from posterior corneal vertex to corneal radius of 4 mm plane) and residual ACD (RACD) (the height from corneal radius of 4 mm plane to the anterior lens surface) were computed.The association between ACD and RACD or LT were assessed by Pearson correlation analysis.Results The ACA,ACV,ACD,RACD and LT were significantly different among various time points before and after LASIK (F =8.319,P<0.05;F =11.596,P<0.05;F =24.045,P<0.01;F =16.087,P<0.05;F =15.333,P<0.01),and the ACA,ACV,ACD and RACD were significantly decreased 1-6 months after LASIK than those before LASIK (all at P<0.05).There were no significant differences in the Sag4 mm ACD between pre-and postLASIK (all at P>0.05).The LT was significantly increased after surgery in comparison with that before surgery (P<0.01).The positive correlations were found between RACD and ACD before LASIK and in 1,3,6 months after LASIK (r =0.976,0.824,0.724,0.938,all at P<0.05) and negative correlation between LT and ACD in 3 and 6 months after LASIK (r=-0.344,P<0.01;r =-0.363,P<0.01).Conclusions The ACD decrease following LASIK mainly in the sector from the plane of cornea 4 mm radius area to lens surface.The change of ACD might be associated with forward shifting of anterior lens surface caused by enhanced accommodation.
10.Evaluation of subendocardial strain and displacement of left ventricle:a canine model with acute myocardial ischemia using velocity vector imaging
Yan BAI ; Lixue YIN ; Zhigang WANG ; Mingliang ZUO ; Huiruo LIU ; Zhiyu GUO ; Yu ZHONG
Chinese Journal of Ultrasonography 2008;17(9):799-804
Objective To assess subendocardial systolic circumferential strain(CS),radial strain(RS)and radial displacement(RD)of left ventricle(LV)in short-axis view and LV global systolic function in open-chest canine model with acute myocardial ischemia using velocity vector imaging(VVI),and to establish their spatial correlationships.Methods Left anterior descending coronary artery(LAD)was ligated for 20 minutes to induce acute myocardial ischemia in 12 open-chest canine model.At baseline and 20 minutes after ischemia,two-dimensional dynamic gray-scale images of three standard left ventricular short-axis views at the levels of mitral annulus,papillary muscle and apex and the images of LV apical fourchamber and two-chamber view were acquired and transfefred to VVI workstation for off-line analysis.Peak systolic CS,RS and RD of eighteen segments and of three global short-axis sections of LV were measured at subendocardium.and LV ejection fraction(LVEF)and stroke volume(SV)were calculated using Simpson's method.The differences and correlationships were analyzed between them.Resuls Compared with the value at baseline,LVEF decreased significantly(P<0.05)after ischemia.The peak systolic subendocardial CS,RS and RD of the affected segments,global CS,RD at papillary muscle and apex views and global RS at apex view were significantly lower than those at baseline after ischemia(P<0.05).There was a good linear correlationship between the peak systolic CS and RD of 17 segments(except the middle segment of LV lateral wall after ischemia)and each global short-axis level before and after ischemia(r=0.662-0.995,P<0.05,P<0.01 or P<0.001),The peak systolic RS of six segments and each global short-axis level(except the apex level at baseline)was correlated with RD(r=0.580-0.916,P<0.05,P<0.01 or P<0.001);There was not statistical correlationship between global RDs and SV as well as LVEF.Conclusions Subendocardial circumferential strain and radial displacement may sensitively reflect the changes of regional and global myocardial systolic function induced by acute myocardial ischemia.The significant correlationship between subendocardial circumferential systolic strain and radial displacement might indicate that circumferential deformation of myocardium result in the changes of the radial displacement mainly.