Aim To introduce an improved method of Langendorff perfusion of the isolated rat heart that is easy to determine the termination of digestion.Methods Hearts were excised quickly from anesthetized SD rats.After the perfusate was free of blood,the solution was changed to perfusion buffer(0.6% Collagenase B,0.6% BSA,30 ?mol?L-1 Ca2+ in Tyrode solution)at 37℃.Hearts were isolated by traditional and improved Langendorff perfusion.Individual myocardial cell was measured by video-based motion edge-detection system(IonOptix,USA).Results One group of heart was digested by traditional Langendorff perfusion for 13~16 min.The termination of digestion could not be judged properly by this method.The nature and quality of the cardiocytes were various.The cardiocytes could not keep their survival and viability when exposed to Tyrode Solution with 1.8 mmol?L-1 Ca2+.Another group was digested by improved Langendorff perfusion.More than 80% survival cardiac ventricle myocytes could be obtained by improved Langendorff perfusion.Moreover,about 50% cardiac myocytes exposed to Tyrode solution with 1.8 mmol?L-1 Ca2+ could retain rod-shaped and be used to contraction research.The contraction of cardiocyte was stabile within 1 000 s.Conclusion Cardiac myocytes disassociated from improved Langendorff perfusion can be used in these studies of detecting contraction and relaxation.This method is economical and easy to control.The beginners are able to acquire the technological method over a short-term practice.

Noticing the phenomenon that biological tissues will change its elasticity by orders of magnitude after it was frozen, we proposed in principle the strategy of using ultrasound elastography to monitor the formation and thawing of the iceball when performing a cryosurgery. Following our former theoretical evaluation, conceptual experiments were designed to apply ultrasound elastography to monitor three kinds of testing samples which includes: phantom embedded with glass block, phantom with tissues at normal temperature and phantom with frozen tissues inside. It was demonstrated for the first time that the ultrasound elastography could provide a high contrast picture on the ice ball during cryosurgery. The measurement errors involved in the application of the method was preliminarily analyzed and approaches to further improve the method were pointed out. With a much different value in elastography than that of water, monitoring the ice ball, the imaging target in clinics, is expected to be an important area for the application of ultrasound elastography.
Cryosurgery ; methods ; Elasticity Imaging Techniques ; methods ; Phantoms, Imaging ; Ultrasonics

Objective To establish an animal model of calpastatin ( CAST) transgenic mice by inserting the full hu-man CAST into the genome of C57BL/6J mice.Methods Recombinant transgenic vector pRP .EX3d-EF1A-CAST-IRES-eGFP was constructed by Gateway technology .It was injected into the fertilized eggs from C 57BL/6J mice.The injected eggs were transplanted into the oviduct of pseudopregnant mice .Tail DNA PCR screening was performed to identify the positive founder mice.The expressions of CAST mRNA and protein in tissues of the transgenic mice were detected by RT -PCR and Western blotting.Results Ninty eggs were transplanted into the oviducts of 3 recipients.The transplantation success rate was 100%.23 viable offsprings were born from the recipients .Tail DNA PCR screening showed that two of the offsprings were positive transgenic mice .The positive rate of transgenic mice was 9%.RT-PCR assay revealed that CAST mRNA ex-pressions were present in the heart , liver, kidney, lung, spleen, brain and skeletal muscle of the transgenic mice .Addition-ally, the CAST protein expression was significantly increased in the transgenic mice .Conclusion CAST transgenic mice have been successfully established and provide a good animal model support for further studies on the CAST function .

ObjectiveTo investigate the diagnosis and treatment of purple urine bag syndrome following transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC).Methods Clinical data of 13 patients who developed purple urine bag syndrome out of 117 patients undergoing TACE for HCC in the Sixth Afifliated Hospital of Sun Yat-sen University between January 2012 and May 2014 were retrospectively studied. Among the 13 patients, 4 were males and 9 were females with the age ranging from 35 to 68 years old and the median of 53 years old. The tumor diameter was≤5 cm in 8 cases and was > 5 cm in 5 cases. The operative duration of TACE was≤30 min in 6 cases and was >30 min in 7 cases. The informed consents of all patients were obtained and the local ethical committee approval had been received. The diagnostic criteria was pink to purple urine in the urine bag after TACE and no blood urine detected by urine routine test.ResultsThe incidence of purple urine bag syndrome following TACE was 11.1% (13/117). After purple urine bag syndrome was confirmed, the patients were given the comprehensive therapy of urine acidification, rehydration, regular change of urinary catheter and urine bag, and gastrointestinal function improvement. No anti-infective therapy was given. The average indwelling time of urinary catheter was (12±3) d.ConclusionsIt is not a rare case for purple urine bag syndrome following TACE for HCC, thus it should be taken seriously. The treatment mainly includes urine acidiifcation, rehydration and gastrointestinal function improvement.

Objective To investigate the clinical efifcacy of transcatheter arterial chemoembolization (TACE) combined with radiofrequency ablation (RFA) in treatment of liver metastasis of colon cancer. Methods A total of 68 patients with liver metastasis of colon cancer in the Sixth Affiliated Hospital of Sun Yat-sen University from June 2007 to May 2011 were enrolled in this prospective study. The informed consents of all patients were obtained and local ethical committee approval had been received. There were 43 males and 25 females with a mean age of (59±4) years old. The patients were divided into RFA group and Control group with 34 cases in each group according to random number table method. Patients in both groups underwent TACE ifrstly and patients in RFA group underwent RFA 3 weeks after TACE treatment. Cluster of differentiation (CD) 3+, CD4+, CD8+positive cell percentage and CD4+/CD8+ratio were deifned by flow cytometry before and after treatments in two groups. The tumor diameter after treatments and general efifcacy were observed. The patients were followed up and the tumor recurrence and survival of the patients were observed. The comparisons of tumor diameter and immune function between two groups were conducted using t test. The comparison of efifcacy between two groups was conducted using rank sum test. The survival analysis was conducted using Log-rank test and Z test. Results The CD4+, CD8+percentage and CD4+/CD8+ratio were (42±4)%, (13±3)%, 2.9±0.9 in RFA group after treatment and were (33±4)%, (17±3)%, 2.3±0.9 in Control group, where signiifcant differences were observed (t=5.483,-6.488, 9.321;P<0.05). The tumor diameter in RFA group after treatment [(0.9±0.1) cm] was significantly smaller than that in Control group [(1.9±0.2) cm] (t=-4.573, P<0.05). The total effective rate in RFA group was 62%(21/34) and was 35%(12/34) in Control group. The treatment efifcacy of RFA group was better than that of Control group (Z=4.769, P<0.05). The 2-, 3-year survival rates in RFA group (38.2%, 23.5%) were significantly higher than those in Control group (14.7%, 5.9%) (Z=4.836, 4.221; P<0.05). Conclusions TACE combined with RFA is a safe and effective regimen in treating liver metastasis of colon cancer. The efifcacy may be associated with the improvement of the body’s immune function.