Objective To investigate the effects of sevoflurane preconditioning on renal ischemia-reperfusion(I/R)injury in rats.Methods Twenty-four adult male SD rats weighing 250-300 g were randomly divided into 3 groups(n=8 each):sham operation group (group S);I/R group; sevoflurane preconditioning group (group SP). After the rats underwent right nephrectomy, renal I/R was produced by occlusion of left renal artery for 45 min followed by reperfusion in I/R and SP groups.In group SP, the rats inhaled 2.2% sevoflurane for 1 h, then the inhalation was stopped and renal ischemia was performed 10 min later. Venous blood samples were collected at 2 h of reperfusion to determine the concentrations of serum creatinine(Cr), urea nitrogen (BUN), cystatin C (Cys C) . The renal tissues were obtained for microscopic examination, and Paller's score was recorded. Results Compared with group S, there was no significant difference in the serum Cr and BUN concentrations (P＞0.05), while the serum Cys C concentration and Paller's score for acute renal tubular injury were significantly increased in group I/R(P＜0.05). The serum Cys C concentration and Paller's score were significantly lower in group SP than in group I/R(P＜0.05).I/R-induced renal injury was significantly reduced in group SP compared with group I/R. Conclusion Preconditioning with sevoflurane can provide significant protection against renal I/R injury.

Objective To evaluate the effect of sevoflurane preconditioning on the expression of heat shock protein 70 (HSP70) during renal ischemia-reperfusion in rats.Methods Twenty-four pathogen-free healthy adult male Sprague-Dawley rats,weighing 250-300 g,aged 2-3 months,were divided into 3 groups (n=8 each) using a random number table:sham operation group (group S),renal I/R group (group I/R) and sevoflurane preconditioning group (group SP).The animals were anesthetized with 2％ pentobarbital sodium 50 mg/kg.After the right kidney was removed,the left renal artery was clamped for 45 min followed by 2 h reperfusion to establish the model of renal I/R injury.In group SP,2.2％ sevoflurane was inhaled for 1 h followed by 10-min washout before the model was established.The animals were sacrificed at the end of rcpcrfusion,and kidneys were then removed for determination of the expression of HSP70 (by immunohistochemistry) and malondialdehyde (MDA) content in renal tissues (by thiobarbituric acid colorimetric method).Results Compared with group S,the expression of HSP70 in renal tissues was significantly up-regulated,and the MDA content in renal tissues was increased in t/R and SP groups (P＜0.05).Compared with group I/R,the expression of HSP70 in renal tissues was significantly up-regulated,and the MDA content in renal tissues was decreased in group SP (P＜0.05).Conclusion The mechanism by which sevoflurane preconditioning reduces renal I/R injury is related to up-regulation of HSP70 expression in rats.

Objective To investigate the effect of the modified surgery for spontaneous rupture of esophagus (SRE) so as to improve treatmeut level.Methods Clinical data and surgical methods of 16 SRE patients including four patients with mid-esophagus ruptures and 12 with lower esophagus ruptures treated between February 1999 and June 2011 were analyzed retrospectively.All patients had only one laceration with the gap length of 1.5-5 cm (median 2.5 cm).Eleven patients had rupture into the left breast,two had rupture into the right chest,with no rupture into the chest in three patients.Ten patients suffered from hydropneumothorax and five from subcutaneous emphysema.Thc esophageal mucosas rathcr than muscular layers of all patients were sutured disconnectedly with absorbable thread.Omentum majus were embedded and fixed to muscular layer on the edge of esophagus rupture site.Fundus ventriculi were suspended and fixed to the dome of diaphragm.In the meantime,diaphragmatic hiatus were reconstructed above the esophagus rupture site for lower esophagus ruptures.Results The time from SRE attack to operation ranged from one hour to three days.Eleven patients were repaired within 24 hours of SRE onset and five patients were repaired after 24 hours of SRE onset.All patients got through the perioperative period smoothly and survived the operation with cure rate of 100％.The median hospital stay was 18.5 days.No esophageal narrow or canceration were found during follow-up (range,1-10 years),but two patients suffered from reflux which were relieved significantly after conservative treatment.Conclusion For treatment of SRE,interrupted suture for esophageal mucosal layers,omentum majus embedding instead of esophageal muscular layer suture and simultaneous anti-reflux operations can significantly reduce incidence of complications like esophageal fistula,stenosis and reflux and improve the cure rate.

Objective To investigate the effect of early coronary artery bypass grafting (CABG)to the left ventricular wall motion state and the significance of CABG to awake hibernating myocardial in dogs with acute myocardial infarction.Methods The anterior descending coronary of all thirty dogs were ligated into MI model.According to the operation date,the experimental groups included the 1 st week (n =6),the 2nd week (n =4),the 4th week (n =6) and the 6th week (n =6) CABG,and established control group (n =2) for every experimental group.Operators marked hibernate myocardial and determined the room wall motion score by means of dobutamine ultrasound load test (DSE) combining with tissue doppler imaging (DTI)technology before CABG and after eight weeks CABG through thoracotomy surgery for the experimental group and the control group.Every dog was executed and detected the area of MI.Results Four dogs of experimental group and all dogs of control group survived to the end of the study.The change of ventricular room wall motion score in the 1st and the 2nd week CABG was smaller than that in the 4th and the 6th week CABG and MI group(0.03 ±0.06,0.05 ±0.09,0.23 ±0.08,0.27 ±40.06,0.32 ±0.05,P ＜0.05).The change of room wall motion score in all CABG groups was smaller than that in MI group(1.195 ±0.09,1.25 ±0.18,1.30 ±0.18,1.36 ±0.11,1.65 ±0.17,P＜0.05).The hibernate myocardial were more awaken in all CABG groups than that in MI group (0.27 ± 0.12,0.22 ± 0.04,0.31 ± 0.09,0.23 ± 0.03,0.03 ± 0.04,P ＜ 0.05).The area of MI became smaller in 1 and 2 weeks CABG than that in 4 and 6 weeks CABG and MI group(20.75 ± 2.63,21.25 ± 2.5,27.25 ± 1.71,27.75 ± 2.22,P ＜ 0.05).Conclusions Early CABG surgery for dogs acute MI could improve the ventricular room wall motion obviously and wake up more hibernate myocardial.Especially,CABG surgery among two weeks could lessen the effect of MI to the ventricular room wall motion and reduce the scope of myocardial infarction maximatily.

According to literature, the incidence of three-canal maxillary first premolar is between 0.5% and 7.5%. The two types of three-canal maxillary premolars are two-rooted and three-rooted three-canal maxillary premolars. Most case reports in Chinese literature focus on three-rooted three-canal maxillary premolars. To our knowledge, no domestic case report on two-rooted three-canal maxillary premolar has been published. In this study, we describe the root canal treatment of a two-rooted three-canal maxillary premolar.

Objective To discuss clinical application,value and effect of tracheal stent in surgical operation for tracheostenosis caused by thyroid tumor.Methods Clinical data of 6 patients with tracheal stenosis and dyspnea caused by thyroid tumor invasiveness or tracheal compression from Oct.2015 to Sep.2016 were retrospectively analyzed.Of the 6 patients,1 case had nodular goiter and 5 cases had differentiated thyroid carcinoma(DTC).Results All patients had dyspnea caused by thyroid tumor invasiveness or tracheal compression.Dyspnea relieved dramatically after tracheal stent was implantated under local anesthesia.Thyroidectomy was given later,with intraoperative tracheal intubation as well as anesthesia,and the surgery finally succeeded.One case with benign multinodular goiter received complete resection and 5 cases with DTC invading the trachea received complete resection of thyroid and neck lymph node dissection,followed by end-to-end anastomosis of invaded trachea sleeve resection.All patients got stage Ⅰ healing in surgical wound.Five cases received radioactive 131I treatment as well as TSH suppression therapy after DTC surgery.All patients were alive and disease-free after a follow-up of 4 to 15 months.Conclusions For patients with tracheostenosis caused by thyroid tumor invasiveness or tracheal compression,operation under cardiopulmonary bypass is necessary if tracheal intubation is difficult.For hospitals without cardiopulmonary bypass,tracheal stent implantation can effectively relieve dyspnea symptom and reduce risk of tracheal intubation under anesthesia,which provides possibility for surgical treatment.

Objective To investigate the radioprotective effect of cimetidine on survival rate and hematopoietic system in acutely irradiated mice.Methods The total body irradiation doses were 6.0Gy and 8.0Gy respectively at 1.01Gy/min rate. Sixty healthy male C57BL/6 mice were randomly divided into control group, model group, positive-drug (523) group and cimetidine groups (33.3mg/kg, 100mg/kg and 300mg/kg). Each group had ten mice. The mice were given intragastric administration of cimetidine for 6d before the irradiation in cimetidine groups, and 523 was administered before irradiation once a day for one day in 523 group, and at 5h after irradiation, was given again. The 30d survival rate after 8.0Gy irradiation was recorded. The peripheral blood cells, bone marrow DNA content and frequency of micronucleated polychromatic erythrocytes (fMNPCE) were determined 30d after 6.0Gy irradiation.Results After 8.0Gy irradiation, all the mice died on 21th day in model control group. The survival rates in cimetidine groups were 50%, 20% and 30%, respectively. After 6.0Gy irradiation on 30th day, compared with control group, the peripheral white blood cells (WBC) and bone marrow DNA content were decreased significantly (P<0.01,P<0.05) in model group, and fMNPCE was increased significantly (P<0.05). Compared with model group, WBC was significantly increased in 300mg/kg cimetidine group (P<0.01). In cimetidine groups, the bone marrow DNA content was increased significantly after irradiation (P<0.01 orP<0.05), and the fMNPCE was decreased significantly (P<0.01 orP<0.05) and tended towards normal.Conclusion Cimetidine could improve 30d survival rate of acutely irradiated mice and has good protective effect on hematopoietic system.

Objective The study aimed to explore the main forms of double minute chromosomes(DMs)in the cell cycle of colorectal cancer at different phases,and to clarify the replication and separation phases of DMs.Methods After using serum-free starvation to block the progression of cell cycle in colorectal cancer COLO 320DM cells,Calyculin-A was used to induce interphase cells to prepare karyotype samples through advanced chromatin condensation.COLO 320DM cells were treated with colchicine to ob-tain mitosis(M)phase cells for karyotype analysis.The karyotypes of cells at the early stage of DNA synthesis(G1 phase),the late stage of DNA synthesis(G2 phase),metaphase(M-mid),anaphase(M-late),and telophase(M-ter)of mitosis were observed and photographed under a regular optical microscope,and counted the number of DMs.Results DMs mainly existed in monotypic form at the G1 phase,M-late phase and M-ter phase of cells.In the G2 and M-mid phases of cells,DMs mainly existed in a diploid form.Conclusion Monomeric DMs undergo replication in the S phase and transform from monomers to diploids,while diploid DMs in the M-late phase complete separation and transition from diploids to monomers.