Objective　To study the effects of ACE1 on amount and mRNA expression of Ca2+ release channels(RyR2) of myocardial sarcoplasmic reticulum(SR) in prevention and treatment of chronic heart failure.Methods　After the model of chronic heart failure was established with ligation of left corongary artery in rats,the animals were prevented and treated with Perindopril. Hemodynamic parameters, Bmax and Kd of ［3H］－ryanodine binding to RyR2、RyR2 mRNA content were determined.Results　Compared with the control group(group C),LVEDP in the heart faliure group (group F)increased(P<0.01),while+dp/dtmax and -dp/dtmaxdecreased significantly(P<0.01).LVEDP was lower but +dp/dtmax and -dp/dtmaxsignificantly higher in the Perindopril treated group(group P)than those in group F(P<0.01).Bmaxof ［3H］－ryanodine binding to RyR2 and mRNA content of RyR2 in group F were lower than those in group C(P<0.01),and these in group P were higher than those in group F(P<0.01). There were no significant difference of Kd among the three groups(P>0.05).Conclusion　The amount and mRNA expression of RyR2 of myocardial sarcoplasmic reticulum(SR) decreased in chronic heart failure.Perindopril can improve mRNA expression and amount of RyR2 of myocardial SR in prevention and treatment of chronic heart failure, thus contributing to the improvement of myocardial function.

This article aims to introduce the progress, mechanism, advantage, disadvantage and application of cryoablation technique, as well as the most advanced instruments in the world nowadays, which have been clinically used for the treatment of cancer, and their operating principles and functions.The following are some of the state-of-the-art cryoablation instruments:the ArcticFront balloon catheter for the ablation of pulmonary vein(CryoCath Technologies Inc., Canada), the V-probe(Endocare Inc., U.S.A.), which can generate iceball of five different diameters by adjusting the slip-twisting position, the 1.47 mm diameter probe(Galil-medical Inc., Israel), the Cryo-s(Metrum-cryoflex Inc., Denmark), and cryosurgery-hyperthermia equipment and"nano frozen"technique(Liu Jing's Study Group).The prospect of cryoablation technique is also discussed in this paper.

Objective To evaluate which b value is the best to distinguish the glioma recurrence and radiation-induced brain injury using DWI when b value were at 1 000 s/mm2、3 000 s/mm2 and 5 000 s/mm2 respectively.Methods Retrospective analysis the DWI of 21 patients who suffered from glioma recurrence and radiation-induced brain injury obtained on a 3T MRI scanner.Results (1)All recurrent glioma (100%)showed hyper-intense signal,while most radiation-induced brain injury patients (80%)showed hypo-in-tense signal when b=5 000 s/mm2 .The sensitivity and specificity were high (100% and 80% respectively)when hyper-intense sig-nal was taken as a diagnostic point of glioma recurrence and radiation-induced brain injury.(2)The receiver operating characteristic (ROC)curve analysis suggested that the minimum ADC resulted in a highest sensitivity to differentiate glioma recurrence from radi-ation-induced brain injury when b=5 000 s/mm.Conclusion High b-value is more accurate to reflect cell density,and the minimum ADC is better to differentiate the glioma recurrence and radiation-induced brain injury when b=5 000 s/mm2 on DWI.

Objective To study the mechanism of carvedilol therapy of congestive heart failure. Methods After chronic heart failure model was established by ligation of the left coronary artery in rats, rats were treated with carvedilol and terazosin. Then hemodynamic parameters, activity of sarcoplasmic reticulum(SR) Ca 2+ pump(SERCA 2a ) and the rate of cardiomyocyte apoptosis were determined. Results Compared with those of the control group( group C), the activity of SR Ca 2+ pump in the heart failure group(group F) decreased( P 0.05). Carvedilol intervention reduced the rate of cardiomyocyte apoptosis, but enhanced the activity of SR Ca 2+ pump significantly in dose dependent manner. The activity of SR Ca 2+ pump was negatively correlated with the rate of cardiomyocyte apoptosis( r =-0.814, P

Objective To investigate the result of local injection of growth differentiation factor-5 (GDF-5) and fibrin gel for treatment of lumbar disc injury in rabbits.Methods Lumbar puncture with a 20-gauge needle was performed at L3/4,L4/5,and L5/6 discs of 40 New Zealand white rabbits.After needle puncture,L3/4 discs were injected with GDF-5 and fibrin gel (compound group) ; L4/5 discs fibrin gel (fibrin gel group) ; L5/6 discs nothing (blank control group).Two weeks later,intervertebral disc degeneration in each group was observed via radiography,MRI and nucleus proteoglycan content detection and histological examination.Results At postoperative 2-,4-,8-,and 12-weeks,X-ray films revealed a gradual decrease in disc height index (DHI) among the three groups,but the decreasing velocity was lower in compound group than in other two groups (P ＜ 0.05).On MRI,the signal of intervebral discs among the three groups diminished progressively with time,but a relatively lower decreasing was observed in compound group (P ＜ 0.05).At postoperative 4-week,proteoglycan content of the nucleus pulposus was (6.3-± 0.4) in compound group,higher than (5.9-0.4) in blank control group and (5.8-± 0.3)in fibrin gel group (P ＜0.05).At postoperative 2-week,histological evaluation showed (5.28 ±0.41)points in compound group,lower than (7.54 ± 0.53) points in blank control group and (7.21 ± 0.44)points in fibrin gel group (P ＜ 0.05).Conclusion Local injection of GDF-5 and fibrin gel facilitates the restoration of the injured discs and delays further disc degeneration.

Objective To explore the sensitivity of a little amount of subarachnoid hemorrhage (SAH) between CT and different MR sequences through animal experiment,to find a more sensitive way to diagnosis SAH.Methods 18 healthy adult white New Zealand rabbits were randomly divided into two experimental groups(group A and group B) and one control group(group C).Rabbit SAH model was established by injecting blood into the cisterna magna one time.All rabbits underwent CT and MR scan at 2 hours,48 hours after operation.The findings on CT and different MR sequences were observed and recorded.Results ①In experimental groups(group A and group B),MR FLAIR sequences in the diagnosis of a little amount of SAH was more sensitive than that on MR T1WI,T2WI and CT in acute phase.And the diagnosis sensitivity between MR FLAIR and CT was statistically significant(P<0.05).②Abnormal signs of SAH could not be found in group C.Conclusion ①Rabbit SAH model was established successfully which will be the foundation for the follow-up study of medical imaging.②MR FLAIR sequence is more sensitive to diagnose a little amount of SAH in acute phase,and may be used in the routine diagnosis of SAH in acute phase.

BACKGROUND:Among the factors causing vascular endothelial cell injury,angiotensin Ⅱ(Ang Ⅱ) caused by renin-angiotensin system (RAS), especially by local RAS, plays an important patho-physiological role.OBJECTIVE: To observe the effect of tanshinone ⅡA on the vascular endothelial cells secreting nitric oxide (NO) and endothelial nitric oxide synthase (eNOS) gene expression as well as intracellular Ca2+ level induced by Ang Ⅱ, and investigate the protective effect of tanshinone ⅡA on vascular endothelial cells.DESIGN: Controlled observation experiment.SETTING: Department of Emergency, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology.MATERIALS: This experiment was carried out in the Experimental Center for Basic Medicine, Tongji Medical College,Huazhong University of Science and Technology from March 2006 to October 2006. Porcine aorta used in this experiment was provided by the Department of Pathophysiology of Tongji Medical College.METHODS: Nitric acid deoxidization method and reverse transcription-polymerase chain reaction (RT-PCR) were used to detect the effects of Ang Ⅱ of different concentrations (10-8 to 10-6 mol/L) on endothelial cells secreting NO and eNOS mRNA expression in cultured porcine aortic endothelial cells at different time points (1,6 and 24 hours) separately, then 50 mg/L tanshinone Ⅱ A was respectively added at different time point (0, 6 hours) when Ang Ⅱ was at 10-6 mol/L, and changes in NO production and eNOS gene expression were detected respectively at 1, 6 and 24 hours. Intracellular Ca2+ level was also detected with laser scanning confocal microscopy.MAIN OUTCOME MEASURES: ① NO content. ②eNOS mRNA expression. ③Intracellular Ca2+ level.RESULTS: ① NO production and eNOS mRNA expression were decreased with increase of Ang Ⅱ concentration and prolongation of time (P ＜ 0.01). ② NO production and eNOS mRNA expression in each tanshinone ⅡA-treated group were significantly higher than those in the Ang Ⅱ group. At 1 and 6 hours of tanshinone ⅡA treatment, production of NO and eNOS mRNA expression in the Ang Ⅱ + tanshinone ⅡA group were significantly higher than those in the Ang Ⅱ 6 hours + tanshinone ⅡA group (P ＜ 0.05); There were no significant differences in NO production and eNOS mRNA expression between two groups at 24 hours (P ＞ 0.05). ③Intracellular Ca2+ level in the Ang Ⅱ group was significantly higher than that of control group (P ＜ 0.01), and intracellular Ca2+ level in the tanshinone ⅡA + Ang Ⅱ was significantly lower than that in the Ang Ⅱ group (P ＜ 0.05).CONCLUSION: Tanshinone Ⅱ A has a protective effect on vascular endothelial cells and their functions by suppressing the inhibition of Ang Ⅱ on NO level and eNOS gene expression in cultured porcine aortic endothelial cells.

Objective To investigate the changes of cardiotrophin-1(CT-1) expression in rats with pressure overload-induced cardiac hypertrophy,and the effects of benazepril on this expression and the concerned cardiac hypertrophy.Methods The model of pressure overload was established by constriction of abdominal aorta and divided randomly into hypertrophied group(LVH,n=7) and benazepril intervention group(Ben,n=7,benazepril 1mg?kg~(-1)?d~(-1) orally)2 weeks later.A sham-operation group(Sham,n=7) served as control.Blood pressure and left ventricular mass index(LVMI) were investigated after 3 weeks' treatment.AngⅡ level in myocardium was measured by radioimmunoassay.The mRNA level of CT-1 was examined by RT-PCR.Results Compared with the sham group, blood pressure and LVMI in LVH group were increased significantly(P

Objective To investigate the changes of GP130 expression in rats with pressure overload-induced cardiac hypertrophy, and the effect of Benazepril on GP130 expression and the concerned cardiac hypertrophy. Methods Two weeks after the Wistar rat model of pressure overload was established by constriction of abdominal aorta, the survived rats were randomly divided into hypertrophy group (LVH, n=7) and Benazepril intervention group (Ben, n=7, 1 mg?kg -1 ?d -1 Benazepril orally for 3 weeks). A sham-operation group (Sham, n=7) was set up as control. Blood pressure and left ventricular mass index (LVMI) were investigated at 3th week after model establishment. AngⅡ level in myocardium was measured by radioimmunoassay. The protein level of GP130 in cardiomyocytes was determined by immunohistochemistry. Results As compared with the Sham group, blood pressure and LVMI increased significantly (P