Objective　To study the feasibility of constructing tissue engineered cartilage by differentiated rabbit bone marrow mesenchymal stem cells(MSC) cultured in vitro and in vivo. Methods　The MSC were isolated from the nucleated cells fraction of autologous bone marrow by density gradient centrifuge, and then induced into chondrogenic differentiation by adding dexamethasone, transforming growth factor-β1(TGF-β1) and ascorbic acid in vitro. After 3 weeks, some cells turned to round shape and secreted metachromatic matrix. The cartilaginoid grafts composed of chondrogenic MSC. Bovine type Ⅰ collagen and human fibrin were cultured within the chondrogenic medium for 2 weeks in vitro or transplanted subcutaneously adjacent to the knee joint for 3 weeks in vivo. Results　The most cells in the grafts were degenerated and disappeared after cultured in vitro. But the residual cells were survival and secreted metachromatic staining proteoglycan with toluidine blue, which was characteristic cartilage matrix. The grafts developed into matured cartilage tissue assessed by histological examination after 3 weeks of transplantation in vivo. Conclusion　MSC can be used as functional cells to constructing tissue engineered cartilage.

Objective　To observe the effect of repairing the articular cartilage defects with tissue-engineered cartilaginous grafts in rabbits. 　Methods　 A total of 60 rabbits were divided into the cartilage graft group, the pure carrier control group and the blank control group. In the cartilage graft group, the bone marrow mesenchymal stem cells (MSCs) of the rabbits were obtained by isolating and culturing the bone marrow aspirates in vitro. The culture system that facilitates the chondrogenous differentiation of MSCs in rabbits was established. The tissue engineering cartilaginous graft was composed of chondrogenetic MSCs, bovine type Ⅰ collagen and human fibrin. Then transplantations of the cartilaginous grafts were performed to repair articular cartilage defects in rabbits. 　Results　Hyaloid cartilage was formed within the defects repaired with the grafts at 12 weeks after transplantation by analyzing the content of type Ⅱ collagen and metachromatism. In the control groups, the fibrous cartilage repair was observed first, then the fibrous tissues and bone repairs were found. 　Conclusions　 The cartilaginous graft through tissue engineering is a promising graft for repairing articular cartilage defects.

Objective To explore the safety and feasibility of vagus nerve-preserving Da Vinci robotassisted radical gastrectomy for gastric cancer.Methods The retrospective cross-sectional study was conducted.The clinicopathological data of 12 gastric cancer patients who underwent vagus nerve-preserving Da Vinci robotassisted radical gastrectomy at the Southwest Hospital of the Third Military Medical University from January 2015 to November 2016 were collected.All patients underwent vagus nerve-preserving Da Vinci robot-assisted radical gastrectomy for gastric cancer.During operation,lymph node dissection of the pyloric region,the right side of the cardia and the superior margin of the pancreas were noticed,and other surgical procedures were the same as the traditional Da Vinci robot-assisted radical gastrectomy.Observation indicators:(1) intra-and post-operative situations:surgical methods,digestive tract reconstruction,operation time,volume of intraoperative blood loss,number of lymph node dissected,results of postoperative pathological examination,recovery time of gastrointestinal function,time for liquid diet intake,duration of postoperative hospital stay,short-term surgery-related complications (postoperative bleeding,anastomotic fistula,obstruction and intra-abdominal infection);(2)follow-up situations:postoperative long-term complications (gastric retention,alkaline reflux gastritis,dumping syndrome,gallbladder disease and cholelithiasis),postoperative quality of life (diet,upper abdominal discomfort,nausea,vomiting and diarrhea),postoperative nutritional status [body weight,hemoglobin (Hb),total protein (TP),albumin (Alb)] and tumor recurrence.Follow-up using telephone interview and outpatient examination was performed up to December 2016.Telephone interview included detecting diet of patients,digestive tract symptoms and body weight.Routine blood test,liver and kidney functions,tumor markers,chest X-ray,abdominal computed tomography (CT) or color Doppler ultrasound and gastroscopy of outpatient examinations were performed to detect tumor recurrence and metastasis.Measurement data with normal distribution were represented as x±s and measurement data with skewed distribution were described as M (range).Results (1) Intra-and post-operative situations:all the 12 patients underwent successful vagus nerve-preserving Da Vinci robot-assisted radical gastrectomy for gastric cancer,without conversion to laparoscopic surgery or open surgery,including 2 patients with D1 lymphadenectomy,2 patients with extended D1 lymphadenectomy and 8 patients with D2 lymphadenectomy.Five and 7 patients underwent respectively Billroth Ⅰ anastomosis and Billroth Ⅱ anastomosis of digestive tract reconstruction.Operation time,volume of intraoperative blood loss and number of lymph node dissected of 12 patients were (247± 34) minutes,(94 ± 23) mL and 27 ± 7,respectively.Results of postoperative pathological examination showed that distal and proximal surgical margins of 12 patients were negative and achieved R0 resection;326 lymph nodes were dissected,6 patients didn't have lymph node metastasis and 18 positive lymph nodes were detected in 6 patients.Recovery time of gastrointestinal function,time for liquid diet intake and duration of postoperative hospital stay in 12 patients were (57±14)hours,(64± 14)hours and (7.3±0.9)days,respectively.There was no occurrence of short-term surgery-related complications.(2) Follow-up situations:12 patients were followed up by telephone interview (10 receiving outpatient exaninations) for 9 months (range,1-20 months).Of 12 patients with long-term complications,2 had loss of appetite,1 had diarrhea,without occurrence of cholelithiasis,cholecystitis,gastric retention and dumping syndrome.Of 10 patients receiving outpatient examinations,body weight,Hb,TP and Alb were (56± 12) kg,(126± 10) g/L,(69.9±5.1) g/L,(43.2±3.3)g/L at 1 month postoperatively and (52±13)kg,(126±10)g/L,(72.1±2.4)g/L,(45.2±1.6)g/L at 3 months postoperatively,respectively,with negative carcinoembryonic antigen.There was no tumor recurrence and metastasis in 12 patients.Conclusion Vagus nerve-preserving Da Vinci robot-assisted radical gastrectomy is safe and feasible for gastric cancer,which has not affected the lymph node dissection and incidence of surgeryrelated complications,and it also can improve the postoperative quality of life and maintain good nutritional status.

Objective: To study the effect of enalapril on inducible atrial fibrillation(AF) in old rats. Methods: Old male Wistar rats were randomly divided into control group(n = 12) and experimental group(n = 13). Rats in control group were fed routinely. Rats were fed with enalapril besides normal diet in experimental group for three months. Rats were then anesthetized, thoracotomy was performed and pericardium was opened to expose heart. Right atrium effective refractory period(ERP) was measured. Sinus conduction time (SCT) and sinus recovery time (SRT) were measured for evaluating sinus function. Interatrial conduction time(IACT) and atrium response to burst pacing were evaluated in vivo. Plasma angiotensinⅡ level and atrial tissue angiotensinⅡ level were determined by radioimmunoassay. Sections were cut from the tissue of atrium and stained with Masson trichrome. The ratio of the area occupied by interstitial to the total area was measured. Results: Contrast to control group,IACT and SRT were shorter in experimental group(P ＜ 0.01 and P ＜ 0.05 respectively). AF were induced in 9 rats in control group and 4 rats in experimental group(P ＜ 0.05). AngiotensinⅡconcentration was significantly decreased in right and left atrium tissues of experimental group compared with that in control group(P ＜ 0.01). A significant decrease in interstitial atrial fibrosis was presented in experimental group compared with that of control group(P ＜ 0.01). Conclusion: Inducible atrial fibrillation rate was decreased in old rats after treatment with enalapril. This effect maybe resulted from the inhibited local atrium renin-angiotensin system and improved sinus node function by enalapril.

Objective To investigate the morphological change and SHP -2(src -homology domain contai-ning protein tygosine phosphatase type 2) gene expression in auditory cortical neuron after auditory deprivation in rat .Methods A total of 48 SD rats were randomly divided into 2-week group ,4-week group ,6-week group ,8-week group and 4 corresponding control groups with 6 rats in each group .Bilateral cochlear ablation was done to traumatized groups to ensure their postoperative ABR threshold was above 90 dB SPL .Then paraffin sectioning and HE and Nissl staining were used to detect morphological change of auditory cortical neuron ,simultaneously the RT-PCR was used to measure the expression of SHP -2 gene in auditory cortical neuron of each group ,and relative quantitative analysis was used .Results The HE and Nissl staining revealed that apoptotic shape of auditory cortical neuron became serious by time ,with the diversified cellular morphology .The relative quantity of SHP -2 gene showed statistical differences between any two groups by the method of one -way ANOVA ,showing a rising trend by time (P<0 .05) .Conclusion Along with time ,auditory cortex ,auditory deprivation showed increasing neuronic apoptosis and neuronic proliferation .Apoptosis was the final result from the mutual antagonism by the 2 factors .

Objective To study human lung adenocarcinoma cell line A-549 treated with antagonist and agonist of potassium channel how to affect metastasis of A-549 and its mechanism. Methods Invasion and migration capability of A-549 in vitro was evaluated by using transwell chamber model. Alteration of cytoskeleton was observed through immunofluorescence. Western blotting were used to detect the protein expression of Ezrin and HuR in A-549 cell lines while Glibenclamde and Pinacidil were applied to them. Results In the presence of the antagonist Glibenclamide, migration of A-549 was inhibited by (57.18±5.46)% and invasion was inhibited by (54.92±3.72)% in the transwell assay, meanwhile A-549 manifested disorder of microtubule and more orderly microfilament. And agonist of the potassium channel had an contrary effect on A-549. Ezrin and HuR protein were successfully down-regulated in A-549 treated with Glibenclamide and upregulated in A-549 treated with pinacidil. Conclusion Functional alterations of the potassium channel affects capability of migration and invision of A-549, which is associated with different expression of ezrin and HuR protein that modify cytoskeleton.

OBJECTIVE To identify the pop strain of Staphylococcus aureus hospital acquired infection by random amplification of polymorphic DNA(RAPD),and to study the molecular mechanism of antibiotic(resistance),so as to reduce the occurrence of drug resistance and infection acquired in hospital.METHODS 1.DNA from 21 strains of S.aureus were extracted by the phenol-chloroform method and analyzed by using arbitrary(primer) polymerase chain reaction(AP-PCR).2.Amplifying mecA,GyrA and GrlA by PCR,and testing the(variation) of these genes by using Hinf Ⅰ-digested analysis.RESULTS Twenty one S.aureus strains were divided into 3(genetic) types.Type Ⅰ is the pop strain in our hospital which including 12 strains.Fourteen from 17 clinical stains were resistant to meticillin and quinolones,of which 13 strains had mecA except isolate 13064.And they all had(variation) in(GyrA) and/or GrlA.CONCLUSIONS RAPD provides markers for the typing of clinical strains and is suitable for(molecular) epidemiologic studies with high type ability,powerful discrimination,simplicity and(rapidness). Type Ⅰ is the pop S.aureus strain in hospital-acquired infection of our hospital.The majority of these strains are multi-(resistant) to meticillin,quinolones and other antibiotics.

OBJECTIVE To study the molecular mechanism of antibiotic resistance in hospital acquired(Staphylococcus) epidermidis infection,so as to reduce the occurrence of drug resistance and infection(acquired) in hospital.METHODS DNA from 18 strains of S.epidermidis were extracted by the phenol-chloroform method,and mecA,gyrA and grlA were amplified by PCR,then the variation of gyrA and grlA was tested by Hinf Ⅰ-(digested)(analysis).RESULTS Fifteen from 18 S.epidermidis strains were resistant to meticillin,and all of them had mecA gene. Eleven from 18 S.epidermidis strains were resistant to meticillin,quinolones and other(antibiotics).And they all had a mutant in gyrA and/or grlA.The mutated spots were gyrA Ser84(TCA→TTA) and GrlA Ser80(TCC→TTC).CONCLUSIONS The majority of hospital acquired S.epidermidis strains are multi-resistant to meticillin,quinolones and other antibiotics,which are caused by acquirement of drug-resistance gene or(mutation) of drug-targeting genes.Medical institutions must strictly standardize the application of antibiotics to(reduce)(development) of drug resistance.

OBJECTIVE To investigate antimicrobial resistance and molecular epidemiology profiles of meticillin-resistant Staphylococcus aureus(MRSA)sampled from lower respiratory tract.METHODS Totally 107 MRSA strains were isolated from lower respiratory tract specimens at Shanghai Pulmonary Hospital between Dec 2005 and Dec 2006.PVL genes were detected by PCR.The genotypes of SCCmec were identified by multiplex PCR.The antimicrobial resistance of MRSA were tested by Kirby-Bauer agar dilution.We also performed the homology of 32 MRSA strains using pulsed-field gel electrophoresis(PFGE).RESULTS All of the 107 MRSA strains were negative in the PVL locus detection and the most frequent SCCmec types were type Ⅲ(81.3%),the others including type Ⅱ(15.9%),type Ⅳ(2.8%),type Ⅰ and type Ⅴ were not found in this group.Those 3 different types of SCCmec were all resistant to ?-lactam antibiotics,less resistant to rifampin,and susceptible to vancomycin,teicoplanin and daptomycin.The resistant rate of those 3 types were different to the non-?-lactam antimicrobial drugs such as trimethoprim/sulfamethoxazole,clindamycin,erythromycin,gentamicin,levofloxacin,and tetracycline,the resistant rate in the types Ⅱ and Ⅲ was significantly higher than the type Ⅳ.PFGE analyses assorted the 32 MRSA strains into 4 PFGE patterns:pulsotype A(25 strains),including subtypes A1(17strains),A2(1 strain)and A3(7 strains);pulsotype B(5 strains),pulsotype C(1 strain),and pulsotype D(1 strain).CONCLUSIONS This study does not found positive PVL locus in the MRSA strains in our hospital,the most frequent SCCmec types are type Ⅲ and some are type Ⅱ.PFGE presented that there are outbreaks of MRSA in ICU ward and TB ward No 5 at that time and the pandemic strains are subtypes A1 and A3,most of these MRSA strains are multiple resistant,which deserves attention from both the clinical staff and infection-control department of the hospital.

Objective To investigate the effect of Propranolol and Phentolamine on neurogenic pulmonary ede-ma(NPE)in rats. Methods One hundred and twenty male Wistar rats were randomly divided into 4 groups:the con-trol group(group A),the NPE group(group B),the Propranolol treatment group(group C)and the Phentolamine treatment group(group D),30 cases in each group. Diffuse brain injury was induced in the latter 3 groups. The lung wet/ dry ratio was calculated. HE staining was used to measure the histological changes in the lung tissues. The levels of neuropeptide Y(NPY)and substance P(SP)in the serum and the bronchoalveolar lavage fluid(BALF)were detected by enzyme - linked immunosorbent assay(ELISA). The expressions of NPY and SP in the lung tissues were demonstra-ted by immunohistochemical staining,and immunohistochemical scores(IHS)were measured after scarifying the ani-mals at different time points(0. 5,6. 0 and 24. 0 h after injury). Results Compared with group A,water volume in the lungs in group B increased at 24. 0 h(P ﹤ 0. 05);NPY content in the serum was elevated at 6. 0 h,while that in BALF was elevated at 6. 0 h and 24. 0 h(all P ﹤ 0. 05);SP content in the serum was elevated at 0. 5 h and 6. 0 h(all P ﹤0. 05),while that in BALF was elevated at 0. 5 h(P ﹤ 0. 05);The expression of NPY protein in the lung tissue in-creased at 0. 5 h,6. 0 h and 24. 0 h(all P ﹤ 0. 05),while the level of SP protein increased at 0. 5 h(P ﹤ 0. 05). Com-pared with group B,water volume in the lungs in group C was higher at 6. 0 h and 24. 0 h(all P ﹤ 0. 05);NPY concen-trations in the serum were higher at 6. 0 h and 24. 0 h(all P ﹤ 0. 05),while those in BALF were higher at 0. 5 h, 6. 0 h,and 24. 0 h(all P ﹤ 0. 05);SP concentrations in serum and BALF were higher at 0. 5 h(all P ﹤ 0. 05). The ex-pression of NPY protein increased at 6. 0 h(P ﹤ 0. 05),while the levels of SP protein increased at 0. 5 h,6. 0 h and 24. 0 h(all P ﹤ 0. 05). Compared with group B,the level of NPY in serum in group D was lower at 6. 0 h,and that in BALF was lower at 6. 0 h and 24. 0 h(all P ﹤ 0. 05). The level of SP in serum was lower at 0. 5 h(P ﹤ 0. 05). The ex-pression of NPY protein decreased at 6. 0 h and 24. 0 h(all P ﹤ 0. 05),while the levels of SP protein decreased at 0. 5 h(P ﹤ 0. 05). Conclusions Phentolamine is effective in reducing NPE through reduction of NPY and SP,while propranolol can stimulate the release of NPY and SP to aggravate NPE following traumatic brain injury in rats.