There are lots of contents in the clinical teaching of cardiothoracic surgery , but the teaching time is short .What should be concerned by every cardiothoracic surgery teacher is how to make full use of the limited time to make students grasp the main contents of cardiothoracic surgery .It is crucial to develop new models of education and assessment .We discuss efforts in our teaching , including new teaching paradigms , teaching tools and multimedia teaching .The combination of varieties of teaching methods , clinical and basic teaching , theory teaching and clinical practice may improve the quality of clinical teaching in cardiothoracic surgery .

Objective To investigate the expression of RCAS1 in the tissues of normal cervix,cervical intraepithelial neoplasia(CIN)and cervical cancer,and to explore their role in the pathogenesis of cervical carcinoma.Methods The expression of RCAS1 protein was analyzed by immunohistochemical S-P method in 89 cases of cervical carcinoma,82 cases of CIN,and 24 cases of normal cervical specimens.Results Immunohistochemistry showed that the expression rate of RCAS1 in normal cervix,CINⅠ,CINⅡ-Ⅲ and cervical cancer were 0.00,0.314,0.447 and 0.775,respectively.RCAS1 expression tended to increase along with tumor progression.The expression of RCAS1 in cervical cancer was significantly related to the histological grade,the tumor in different sizes(≥4cm or 0.05)betwan patients' age,clinical stage and histological classification.Conclusions The data suggested that RCAS1 might play an important role in the pathoqenesis and development of cervical carcinoma.Over expressed RCAS1 could be regard as an important parameter in malignant degree and poor prognosis of cervical cancer.

OBJECTIVE To study the efficacyof the lateral vocal fold injection of autogenous fat for vocal fold insufficiency. METHODS Twenty nine patients with vocal fold insufficiency were treated in our department with fat injection. Deep lateral vocal fold injection was performed through direct laryngoscope under general anesthesia. Fat was injected into the lateral aspect of the vocal fold (paraglottic space) using a special high pressure Brunning injector. The perceptual acoustic,phonatory function,and video laryngostroboscopy were evaluated before and after operation. RESULTS All the patients were followed up for 10 to 18 months. There were 24 patients with excellent results,2 patients with improvement, and 3 patients with no improvement. Phonatory function showed significant improvement(P

This paper is to evaluate the biocompatibility and cytotoxicity of a new Ni-free Zr-based bulk metallic glass (BMG), Zr60.14 Cu22.31 Fe4.85 Al9.7 Ag3, by comparing it with conventional Ti6Al4V alloy. According to ISO 10993-5: 1999 and GB/T 16886.5-1997 standards, Zr60.14 Cu22.31 Fe4.85 Al9.7 Ag3, pure Zr and Ti6Al4V materials were extracted with surface area of sample/volume of medium ratio being 1 cm2/mL and 0.5 cm2/mL, respectively. The viabilities of MG-63 cells (Human osteosarcoma cell line) cultured in the BMG medium extracts for 1, 3 and 5 days were determined by CCK-8 assay. The cellular morphology of MG-63 cells cultured on the surface of samples for 3 days was tested through laser scanning confocal microscopy (LSCM) and scanning electron microscopy (SEM). The relative growth rate (RGR) of MG-63 cells cultured in Zr60.14 Cu22.31 Fe4.85 Al9.7 Ag3 and pure Zr were both more than 85%, indicating that the cytotoxicity of BMG was relatively low and met the national biomedical material eligibility standard. There was insignificant difference in the morphology of MG-63 cells cultured in the BMG medium extracts and the control group through LSCM and SEM, which showed the BMG had excellent biological compatibility. The Zr-based bulk metallic glass Zr60.14 Cu22.31 Fe4.85 Al9.7 Ag3 and the conventional Ti6Al4V alloy both had no obvious cytotoxicity to MG-63 cells. These results provided evidence that the new Zr-based bulk metallic glass could be potential replacement material for the orthopedic surgical implant.
Alloys ; Biocompatible Materials ; Cell Line ; Glass ; Humans ; Microscopy, Electron, Scanning ; Nickel ; Titanium ; Zirconium

Objective To prepare recombinant human epidermal growth factor (rhEGF) sustained-release microspheres and evaluate their morphology, rhEGF releasing activities and cell proliferation activity in vitro and compare difference of rhEGF sustained-release microspheres and rhEGF in facilitaring ulcer healing in diabetic rats. Methods (1) rhEGF sustained-release microspheres were prepared by the modified double emulsion method. Morphology of the microspheres was detected by transmission electron microscope and size distribution measured by laser granularity meter/Zeta electric potential meter. ELISA assays were applied to determine rhEGF releasing. (2)Proliferation of mouse fibroblasts was analyzed by MTr method. (3) Diabetic rat models were prepared and divided into four groups, ie, rhEGF sustained-release mierospheres group (Group A), rhEGF stock solution group (Group B), blank sustainedrelease mierospheres group (Group C) and PBS meustruum control group (Group D), which were given drug once a day. The wound healing rate was calculated by taking photographs at days 3,7,14 and 21. Skin specimens from the wound edge were harvested partially for observation of hydroxyproline (HYP) contents. Immunohistochemistry was employed to detect integrin 131 and keratin-19 and measure their positive staining area ratio. Results (1) The particle diameter of rhEGF sustained-release microspheres was 193.5 nm, with relative uniform particle diameter distribution. There showed no conglutination among rhEGF susrained-release microspheres, with good dispersibility. Releasing drug lasted for 24 hours and accorded with Higuchi release kinetic model. (2) Different concentrations of rhEGF sustained-release microspheres could promote the proliferation of mouse fibroblast, especially the concentration of 10 μg/L (P <0.05, compared with the control). (3) From the 7th day after treatment, Group A had the fastest wound healing rate, with statistical difference compared with other three groups (P < 0.05). Group A had higher HYP contents and positive area ratio of integrin β1 and keratin-19 than Group B. Conclusions rhEGF sustained-release microspheres prepared by the modified double emulsion method have uniform particle size and can last release for 24 hours. Compared with rhEGF stock solution, rhEGF sustained-release microspheres have faster and better ulcer healing and higher healing quality in diabetic rats.

OBJECTIVE The aim of our study was to evaluate the significance of the frequency of microsatellite instability (MSI) and its relationship to mismatch repair gene (MMR) in laryngeal squamous cell carcinoma.METHODS We investigated the expression frequency and clinical significance of MSI and MMR in 50 laryngeal squamous cell carcinoma (LSCC) patients from Beijing Tongren Hospital. The status of MSI was evaluated using microdissection - polymerase chain reaction (PCR) - single strand length polymorphism (SSLP) - silver staining.Five markers on chromosomes 1p, 3p, 5q, 9p, 17p, which were adjacent to BCAR3 (breast cancer anti-estrogen resistance 3), FHIT, APC, CDKN2A (p16), TP53 respectively, were used. Two of the six components of MMR -hMLH1 and hMSH2- were investigated by an immunohistochemical approach because of the high frequency of their downregulation in head and neck tumors. RESULTS The informative case number of the five markers (D17S796, D3S3544, D5S656, D1S375, D9S162) were 44, 42, 45, 44 and 40 respectively. The incidence of MSI was lower than the frequency of loss of heterozygosity (LOH). The incidence of MSI on D17S796 (TP53)was 20.5% (9/44),on D3S3544 (FHIT) was 14.3 % (6/42), on D5S656 (APC) was 31.1% (14/45), on D1S375 (BCAR3) was 20.5 % (9/44), and on D9S162 (CDKN2A) was 15.0 % (6/40). Though there was no relationship between MSI status and age, gender, smoke history, tumor location, tumor differentiation and T stage (P＞0.05),there was a strong correlation between MSI and relapse condition (P＜0.01). Also, MSI status correlated with MMR expression to some degree (P＜0.01), but it was common for negative and positive staining of MMR to coexist on the same slide. CONCLUSION Microsatellite instability and abnormal mismatch repair may contribute to the carcinogenesis of a subset of laryngeal squamous cell carcinoma. Microsatellite instability may be a characteristic signal of tumor recurrence.

Objective We sought to evaluate the efficacy of bipolar radiofrequency ablation of atrial fibrillation (AF) in patients undergoing cardiac surgery,and to determine independent factors affecting the recurrence.Methods From June 2007 through February 2010,81 patients with atrial fibrillation underwent a modified Cox-Maze Ⅳ procedure using a biopolar radiofrequency device( Medtronic in 32 cases,Atricure in 49 cases).There were 45 males and 36 females,aged (48.2 ± 11.0)years,including 26 cases of permanent AF,44 cases of persistent AF and 11 cases of paroxysmal AF.The mean duration time of AF was (7.56 ± 7.47 ) years.The left atrial diameter were 36 ～ 72 mm.In conjunction with cardiac surgery including:mitral valve replacement (MVR) (or add tricuspid valve plasty (TVP) in 33 cases,mitral and aortic valve replacement (DVR)( or add TVP) in 18 cases,off-pump coronary artery bypass surgery (OPCAB) in 16 cases,aortic valve replacement (AVR) in 4 cases,MVR and coronary artery bypass grafting (CABG) in 1 case,mitral valve plasty (MVP) in 1 case,and others in 8 cases.Among them,22 patients were undergoing electrophysiological mapping by high-frequency bipolar stimulation from June 2009 to February 2010.A follow-up of 12 to 44 months was completed.Recurrences were evaluated by 12-lead ECG or 24 hour Holter recording every clinic visit-1,3,6,9,and 12 months after the procedure and yearly thereafter,or if symptoms developed.Multivariate regression analysis was performed to determine independent factors affecting the recurrence.Results Hospital mortality was 1.23％.The successful ablation of AF were 100％,82.5％,and 84.8％ immediately after operation,at discharge,and at 2(6.1 ± 13.6) months after operation respectively.Multinomial regression analysis showed small left atrium ( ＜ 60 mm),and electrophysiological mapping might contribute better sinus rhythm restoration ( P ＜ 0.05 ).Conclusion Bipolar radiofrequency ablation of atrial fibrillation in patients undergoing cardiac surgery is safe and effective.Small left atrium ( ＜ 60mm) and electrophysiological mapping should be considered to improve results in selected patients.

ObjectiveTo investigate the influence of cobalt chloride ( CoCl2 )-mimetic hypoxia on theproliferation,apoptosis and migration of human pancreatic cancer cell fine PANC1.MethodsPANC1 cells were treated with 0(control),100,200,400,800 μmol/L CoCl2 respectively for 24 h.Real-time RT-PCR and Western blot were used to determine hypoxia induced factor ( HIF)-1o mRNA and protein expression respectively,and cell counting kit-8(CCK-8) assays,flow cytometry and cell scratch test were used to examine the proliferation,apoptosis and migration of PANC1 cells,respectively.ResultsIn the control group and 100,200,400 and 800 μmol/L CoCl-2 groups,the expressions of HIF-1t mRNA were 1,1.08 ±0.12,1.12 ± 0.09,1.04±0.11,0.66 ±0.07,and the expressions of VEGF mRNA were 1,2.69±0.35,4.81 ±0.54,2.19 ± 0.21,0.79 ± 0.08,while the expressions of HIF-1 α protein were 0.23 ± 0.03,0.36 ± 0.04,1.15 ± 0.11,1.08 ± 0.09,0.44 ± 0.04; and the expressions of VEGF protein were 0.14 ± 0.02,0.12 ± 0.01,0.95 ±0.09,0.87 ±0.09,0.55 ±0.06; and cell viability rates were 100％,(98.43 ±2.88)％,(76.15 ± 0.70)％,(53.87 ±0.77)％,(35.23 ±0.67)％ ; while cell apoptotic rates were (5.2 ±1.12)％,(5.74 ± 1.07)％,(6.82 ± 1.85)％,(12.09 ±3.53)％,(31.88 ±6.95)％ ; the cell migration distance of PANC1 cells were (43.24 ±3.67)％,(59.46 ±5.39)％,(80.56 ±8.05)％,(63.89 ±5.96)％,(9.09 ± 1.59 ) ％.Compared with those of control group,the expressions of VEGF mRNA,VEGF and HIF-1 α protein,cell migration distance showed a two-way variation ( ascending first and descending later) (P ＜0.05 ),and the expression of HIF-1α mRNA and cell proliferation rate was decreased in a dose-dependent manner,while the cell apoptosis was increased in a dose-dependent manner.Conclusions CoCl2 significantly inhibits the proliferation and promotes apoptosis of PANC1 cells at certain level.CoCl2 has a two-way effect on the migration of PANC1 cells,and it may be related to the direct injury of high concentration of CoCl2 on cells.

[Abstract ] Objective The aim of the study was to investigate the effects of recombinant human erythoropoietin (EPO) and bone marrow mesenchymal stem cell (BMSC) transplantation on renal inflammatory response following cardiopulmonary bypass (CPB). Methods Forty sprague-Dawley male rats were randomly divided into five groups (n=8):shame operation group, CPB group, EPO group, BMSC group and EPO +BMSC group.CPB model was built in shame operation group without CPB .The other four groups un-derwent CPB, following by jugular vein infusion of 1.5 ×106 BMSCs after an hour′s 100 L/kg/min bypass .Jugular vein infusion of 3000 IU/kg EPO was done in EPO group , while the combination of EPO with BMSCs was infused in EPO +BMSC group.The same volume of isotonic saline solution was infused via jugular vein in CPB group and shame operation group respectively .Rats were sacrificed at 24 hours after CPB termination .Blood samples were collected for the determi-nation of creatinine(Cr) and urea nitro(BUN) levels.HE staining was applied in the examination of renal tissues .ELISA was used in the determination of serum interleukin 6 (IL-6) and interleukin 10 (IL-10) levels and western blot was taken to test the expressions of tumor necrosis factor (TNF-α) and insulin-like growth factor 1 (IGF-1). Results In CPB group, the levels of Cr, BUN, IL-6 and the expression of TNF-αwere increased, while IL-10 level and of IGF-1 expression were decreased(P<0.05).TNF-αexpression was increased while IGF-1 expression was decreased in renal tissue (P<0.05).HE staining results showed the renal injury in EPO +BM-SC group was significantly lower than those in EPO group , BMSC group and CPB group , along with the decrease in the levels of Cr , BUN, IL-6, the increase in IL-10 level(P<0.05), as well as the decline of TNF-αexpression and the rise of IGF-1 expression(P<0.05). Conclusion The combination of EPO and BMSCs which reduces renal inflammatory response following CPB has protective effects on renal injury following CPB in rats , which is better than single application of EPO or BMSCs .

BACKGROUND:It has been proved that erythropoietin can promotes angiogenesis in injured tissue, which is closely related to the proliferation and differentiation of endothelial progenitor cel s. However, the involved mechanism remains unclear yet.
OBJECTIVE:To investigate the effect of erythropoietin on the function and activity of bone marrow-derived endothelial progenitor cel s in mice, and to explore the signal pathway.
METHODS:The endothelial progenitor cel s from the bone marrow of mice were separated by means of density gradient centrifugation and then cultured. The cel s were preconditioned by specific inhibitor of PI3K
(LY294002), and were divided into the fol owing groups:EGM-2 group, three erythropoietin preconditioned groups (the concentrations of erythropoietin in medium were 1, 5, 10 U/mL respectively), erythropoietin+LY group (10 U/mL erythropoietin and 10 mmol/L LY294002 in medium), LY group (10 mmol/L LY294002 in medium), dimethyl sulfoxide group (1 mL/L dimethyl sulfoxide in medium). The cel proliferation and apoptosis were evaluated by cel counting kit-8 and flow cytometry respectively. The contents of endothelial nitric oxide synthase and vascular endothelial growth factor in cel lysates were detected by the method of ELISA, and the expressions of Akt and p-Akt were by western blot assay.
RESULTS AND CONCLUSION:Erythropoietin could promote the proliferation of endothelial progenitor cel s in a dose-dependent manner, which was, however, completely inhibited by LY294002. The apoptosis rate in the erythropoietin preconditioned groups was significantly lower than that in the erythropoietin+LY group. The contents of endothelial nitric oxide synthase and vascular endothelial growth factor in cel lysates of LY group and erythropoietin+LY group were significantly lower than those in the erythropoietin groups. There was no difference in Akt expression found in each group, while the p-Akt expression in the erythropoietin+LY group was significantly lower than that in the erythropoietin groups. The above results reveal that erythropoietin can promote the proliferation of endothelial progenitor cel s and decrease the cel apoptosis, which is depending on PI3K/Akt signal pathway.