BACKGROUND:Studies have shown that thymosinβ4 can improve the anti-apoptotic ability of a variety of cells, but the reports describing the changes in the anti-apoptotic ability of bone mesenchymal stem cells modified with thymosinβ4 gene in the hypoxic environment are rare.
OBJECTIVE:To observe the change in the apoptotic rate of bone mesenchymal stem cells modified with thymosinβ4 gene in the hypoxic environment, and to explore whether thymosinβ4 affects the apoptosis of bone marrow mesenchymal stem cells via regulating the expression of Bax and Bcl-2.
METHODS:Bone marrow mesenchymal stem cells were transfected with the recombinant lentiviral vector over-expressing the thymosinβ4 gene, and then we observed the expression of thymosinβ4 using western blot assay. cells were divided into three groups:thymosinβ4 transfection group, control virus group, and untreated group. Al three groups were placed in a hypoxic environment. The apoptotic rate of bone marrow mesenchymal stem cells was evaluated by the flow cytometry assay. The expression of Bax and Bcl-2 protein was detected by western blot.
RESULTS AND CONCLUSION:Thymosinβ4 gene was expressed successful y in the bone marrow mesenchymal stem cells showed by the western blot. The apoptotic rate of bone marrow mesenchymal stem cells in the hypoxic environment was lower in the thymosinβ4 transfection group than the control virus group and untreated group;while there was no difference between the latter two groups. Western blot results showed that the expression of Bcl-2 protein was higher in the thymosinβ4 transfection group than the control virus group and untreated group, and the expression of Bax protein was lower in the thymosinβ4 transfection group than the control virus group and untreated group. No difference in the expression of Bax and Bcl-2 was found between the control virus group and untreated group. These findings indicate that thymosinβ4 overexpression can improve the anti-apoptotic ability of bone mesenchymal stem cells modified in the hypoxic environment, and its possible mechanism is through regulating the expression of Bax and Bcl-2 protein.

The feasibility of bone marrow stromal cells autologous transplantation for rabbit model of dilated cardiomyopathy induced by adriamycin was studied. Twenty rabbits received 2 mg/kg of adriamycin intravenously once a week for 8 weeks (total dose, 16 mg/kg) to induce the cardiomyopathy model with the monitoring of cardiac function by transthoracic echocardiography. Marrow stromal cells were isolated from cell-transplanted group rabbits and were culture-expanded on the 8th week. On the 10th week, cells were labeled with 4,6-diamidino-2-phenylindole (DAPI), and then injected into the myocardium of the same rabbits. The results showed that viable cells labeled with DAPI could be identified in myocardium at 2nd week after transplantation. Histological findings showed the injury of the myocardium around the injection site was relieved with less apoptosis and more expression of bcl-2. The echocardiography found the improvement of local tissue movement from (2.12+/-0.51) cm/s to (3.81+/-0.47) cm/s (P<0.05) around the inject site, but no improvement of heart function as whole. It was concluded bone marrow stromal cells transplantation for dilated cardiomyopathy was feasibe. The management of cells in vitro, the quantity and the pattern of the cells transplantation and the action mechanism still need further research.

Objective To investigate the role of double contrast-enhanced ultrasonography (DCUS) in the diagnosis of rectal gastrointestinal stromal tumors (GISTs). Methods In eleven patients with rectal GISTs before surgery, gastrointestinal ultrasound contrast agent were injected into rectal lumen and tumor’s two dimensional ultrasound features were analyzed. Microbubbles were injected into the vein to investigate the feature of lesion microcirculation perfusion. After the surgery, according to the tumor diameter and mitotic count, rectal GISTs were classified as very low-risk, low-risk, intermediated-risk and high-risk tumors. The very low-risk and low-risk tumors were grouped together as one group while the intermediated-risk and high-risk tumors were grouped together as another group. According to ultrasound performance and pathological type, ultrasonic features of rectal GISTs with different risk levels were estimated. Results Among all rectal GISTs cases, 63.6%(7/11) were low-risk. Under DCUS, the tumor diameter was less than 5 cm, with regular round, hypoechogenicity, uniform low enhancement and less internal liquefaction necrosis. For the 36.4%(4/11) high-risk cases, under DCUS, the tumor diameter was≥5 cm, with irregular round or lobulation, mixed hyperechogenicity and hypoechogenicity, nonuniform high enhancement, large blood vessel and common liquefied necrosis region. The biological behavior of rectal GISTs was relevant to lesion size, liquefaction necrosis and enhancement mode of ultrasound contrast and irrelevant to the bound and shape of lesion. The accuracy of DCUS and contrast-enhanced ultrasonography were 90.9%(10/11) and 72.7%(8/11) respectively. Conclusions DCUS is considered as an effective tool in diagnosingrectal GISTs and can get useful information of the biological characteristics. It has great value for the diagnosis and treatment of rectal GISTs.

The effect of loss-of-function of Attractin (Atrn) on the male mouse reproduction system was examined in the study. The weights and pathological changes of testes and epididymes were compared between Atrn mutant (Atrn ( mg-3J )) mice and wild-type mice (C3HeB/FeJ) at different months of age. The number and motility of sperms were measured in the mutant and control mice. Furthermore, the testicular lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH) in these animals were detected. The fertility potential of the sperms was observed in vivo and in vitro. The results showed that the testes of 3-month-old Atrn ( mg-3J ) mice experienced no significantly different pathological changes from the control mice at the same month of age but the SDH activity was substantially reduced. In the 5-month-old mutant mice, as compared with the control mice, mild vacuolation was found in the testes, the density and motility of sperms were decreased in the epididymes, the sperm fertility was impaired and the testicular enzyme activity was reduced. It is concluded that the age-related Atrn gene progressively loses its function and can cause testis vacuolation and impaired sperm function, which may be responsible for the impairment of male reproductive ability.

Objective To evaluate the imaging diagnosis of anomalous origin of coronary artery from the pulmonary artery(ACAPA).Methods A total of 11 cases with ACAPA were included in the present study.Chest films,echocardiography,cardioangiography,and electron beam computed tomography (EBCT) were employed as diagnostic modalities.Macroscopic anatomy at operation was referred. Results Ten cases were classified as anomalous origin of left coronary artery from the pulmonary artery(ALCAPA) and 1 case as anomalous origin of right coronary artery from the pulmonary artery(ARCAPA).They could not be diagnosed by chest films,but could be diagnosed by echocardiography in 3 cases,by EBCT in 1 case,and by cardioangiography in all cases.In ALCAPA,cardioangiography showed that the left coronary arteries arising from the posterior sinus or posterior wall of the pulmonary artery were perfused retrogradely via the collaterals from the dilated right coronary artery.In ARCAPA,the right coronary artery originated from the right sinus of the pulmonary artery.Gross anatomy at operation showed that the sites of the anomalous origins were the same as that of cardioangiography.Ischemic fibrosis of the anterior papillary muscles,mitral valve annulus enlargement,and prolapse of mitral valve,which led to mitral valve insufficiency,were found in 3 cases.Conclusion Chest film has limitation in the diagnosis and echocardiography should be further improved.Cardioangiography remains the “gold standard” of the preoperative diagnosis.

Objective To evaluate the effect of self-expandable occluder on closure of patent ductus arteriosus(PDA)with severe pulmonary arterial hypertension(PH)in adults.Methods Twenty-eight adult patients underwent transcatheter closure of PDA at a mean age of(31.3?11.6)years [(18—58)years].Either Amplatzer duct occluder or domestic device was used in the present study.X-ray,EKG and UCG were repeated in one day,one month,three months,and six months.Results Twenty of the 28 patients had successful occlusion,and the other 8 patients were given up.In the successful group,the narrowest diameter of PDA was(10.4?2.7)mm [(6—16)mm],the diameter of selected occluder was(15.6?3.2)mm [(10—20)mm] at the end of pulmonary artery.Systemic artery oxygen saturation(SAsat)before and after oxygen inhalation was(93.5?1.8)%,(98.2?1.8)%,respectively(P

The feasibility of bone marrow stromal cells autologous transplantation for rabbit model of dilated cardiomyopathy induced by adriamycin was studied. Twenty rabbits received 2 mg/kg of adriamycin intravenously once a week for 8 weeks (total dose, 16 mg/kg) to induce the cardiomyopathy model with the monitoring of cardiac function by transthoracic echocardiography. Marrow stromal cells were isolated from cell-transplanted group rabbits and were culture-expanded on the 8th week. On the 10th week, cells were labeled with 4,6-diamidino-2-phenylindole (DAPI), and then injected into the myocardium of the same rabbits. The results showed that viable cells labeled with DAPI could be identified in myocardium at 2nd week after transplantation. Histological findings showed the injury of the myocardium around the injection site was relieved with less apoptosis and more expression of bcl-2. The echocardiography found the improvement of local tissue movement from (2.12±0.51) cm/s to (3.81±0.47) cm/s (P＜0.05) around the inject site, but no improvement of heart function as whole. It was concluded bone marrow stromal cells transplantation for dilated cardiomyopathy was feasibe. The management of cells in vitro, the quantity and the pattern of the cells transplantation and the action mechanism still need further research.

The effect of loss-of-function of Attractin (Atrn) on the male mouse reproduction system was examined in the study. The weights and pathological changes of testes and epididymes were compared between Atrn mutant (Atrnmg-3J) mice and wild-type mice (C3HeB/FeJ) at different months of age. The number and motility of sperms were measured in the mutant and control mice. Furthermore,the testicular lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH) in these animals were detected. The fertility potential of the sperms was observed in vivo and in vitro. The results showed that the testes of 3-month-old Atrnmg-3J mice experienced no significantly different pathological changes from the control mice at the same month of age but the SDH activity was substantially reduced. In the 5-month-old mutant mice,as compared with the control mice,mild vacuolation was found in the testes,the density and motility of sperms were decreased in the epididymes,the sperm fertility was impaired and the testicular enzyme activity was reduced. It is concluded that the age-related Atrn gene progressively loses its function and can cause testis vacuolation and impaired sperm function,which may be responsible for the impairment of male reproductive ability.

ObjectiveTo assess the value of free-breathing 3D phase sensitive inversion recovery (PSIR) turbo FLASH for demonstrating the left ventricular myocardial scar in patients with myocardial infarction.MethodsTwenty-three patients with myocardial infarction underwent 2D and 3D phase sensitive inversion recovery (PSIR) Turbo FLASH sequences 10-15 minutes after injection of dimeglumine gadopentetate.The image quality,the area,location and volume of hyperenhanced scar were independently assessed by two experienced radiologists.Student′s t test or rank sum test and Pearson linear correlation were used for the statistics.ResultsThere were no significant differences in the overall image quality (2.57 ±0.59 vs 2.39 ±0.66,Z=-0.93,P =0.35),the area (24.48 ±10.83 vs 29.00 ± 11.56,Z=-1.41,P =0.16) and location ( 16.78 ± 6.51 vs 18.87 ± 6.76,Z =- 1.17,P =0.24) of hyperenhanced scar between 2D and 3D PSIR sequences.The mean volume of hyperenhanced scar was significantly greater in 3D PSIR sequence than that in 2D PSI R sequence [(23.46 ± 10.61 ) vs (31.65 ±　 13.86) cm3,t =-2.25,P =0.03].There was a good correlation in the volume of hyperenhanced scar between 2D PSIR and 3D PSIR sequences (r=0.940,P＜0.01 ;y =2.851 + 1.228x,R2 =0.883).ConclusionFree-breathing 3D PSIR Turbo FLASH is a promising new imaging technique for accurate assessment of myocardial scar.

Objective To evaluate the efficacy of MRI for assessment of re-distribution of bone marrow mesenchymal stem cells injected intramyocardially in main organs (heart, liver, spleen and kidney) under different heart status (beating or arresting) in a porcine model. Methods Bone marrow-derived mesenchymal stem cells were obtained from the male swine and labeled with iron oxide during culture. Acute myocardial infarction was created in female swine, one week later, the survivors were randomly divided into 4 groups. Cardiopulmonary bypass was set up to arrest the heart, and then labeled cells (1×108) were intramyocardially injected into the border of the infracted myocardium in group 1 (n=6). The same volume of cells was grafted into the beating heart in group 2 (n=6). In group 3 and 4, saline was injected into either the arresting or beating myocardium. Three days later, re-distribution of stem cells and cardiac function were assessed by T2*WI and cine MRI, respectively. All animals were sacrificed for histology and real-time quantitative polymerase chain reaction (RT-PCR) of sex-determining region on Y-chromosome (SRY) investigation.The ANOVA and t test was used for statistics. Results The left ventricular end-diastolic volume (LVEDV) before transplantation for group 1-4 were: (56.8±5.3),(54.8±6.8),(57.4±4.3)and(56.8±2.8) ml, and after transplantation for group 1-4 were: (65.2±5.2),(63.2±3.7),(60.2±4.7)and(62.2±4.4) ml. The left ventricular end-systolic volume (LVESV) before transplantation for group 1-4 were: (33.5±7.6),(32.3±5.3),(33.5±3.6)and(32.7±4.6) ml,and after transplantation for group 1-4 were: (37.3±5.6),(36.3±6.9),(34.3±5.4)and(36.3±8.1) ml. The left ventricular EF values (LVEF) before transplantation for group 1-4 were: (42.3±7.2)%,(41.7±6.8)%,(41.8±8.6)% and(42.7±7.7)%,and after transplantation for group 1-4 were: (44.5±8.7)%,(43.1±7.4)%,(42.8±5.6)% and(43.3±8.4)%. The myocardial infarction area (MI) before transplantation for group 1-4 were: (6.5±2.1),(6.4±1.9),(6.5±2.5)and(6.4±2.6) cm2,and after transplantation for group 1-4 were: (6.4±2.3),(6.2±2.6),(6.3±2.5)and(6.4±2.8) cm2 . There were no statistical differences before and after transplantation in these 4 groups[P values of before and after transplantation for LVEDV, LVESV, LVEF,MI were >0.05 (F= 0.277, 0.066,0.066, 0.003); and >0.05 (F= 1.137,0.182,0.021,0.008),respectively]. The T2 value of the infracted myocardium in group 1 decreased more obviously than that in group 2[(-22.3 ± 2.2) vs (-17.0 ± 0.8) ms, t=-5.489, P＜0.01], while the T2 value of the spleen decreased more significantly in group 2 than that in group 1[(-7.7 ± 0.7) vs (-13.3 ± 1.1) ms,t=9.055, P＜0.01]. The T2 values of the liver and kidney were no significant differences in group 1 and 2 (liver, t=-0.532,P>0.05 and kidney, t=-0.113,P>0.05). The results of RT-PCR in group 1 and 2 showed significant differences in heart[(150±62) vs (72±4) U/L ,P<0.05, t=3.109], spleen[(131±1) vs (233±17) U/L, P＜0.01, t=- 13.286]and liver[(17±1) vs (9±5) U/L ,P<0.01,t= 3.492]. Pathological examination demonstrated that the transplanted stem cells were positive for Prussian blue staining, which had a good correlation with MRI results. Conclusion MRI can serve as a convenient and efficient imaging method to track the migration of stem cells with SPIO labeled in early stage and evaluate its early re-distribution in vivo. Injection of bone marrow mesenchymal stem cells in the arresting heart could favor retaining more cells in the myocardium.