Objective To observe whether coagulation zones can be produced by intraductal radiofrequency ablation (RFA) in vivo and investigate the effect of portal blood flow on the sizes of coagulation zones. Methods Fourteen bile duct targets in hepatic hilar from 6 swines were equally divided into non-Pringle manoeuvre group and Pringle manoeuvre group. A 13mm segment of non-insulated mono-electrode was inserted into the bile duct, then RFA was performed under the condition of 5 W power output for 4 minutes. The pathological changes of bile duct and adjacent hepatic tissues were observed. Results Semi-oval offwhite coagulation zones in the sections were observed in both groups, with obvious dark-red rims around them. Necrosis and denaturation of mucosal and submucosal layers of bile duct and denaturation of adjacent hepatic tissue in coagulation zones were observed under optical microscope. The dark-red rims revealed hepatic hemorrhage. The mean long axial diameter of coagulation zones in the non-Pringle manoeuvre group and Pringle manoeuvre group was (13.29±1.38)mm and (13.29±1.1 1)mm, respectively, with no statistical difference (t=0.000, P>0.05). The mean short axial diameter of coagulation zones in the non-Pringle manoeuvre group and Pringle manoeuvre group was (3.14±1.07)mm and (4.57±0.98)mm, respectively, with statistical difference (t=2.611, P<0.05). Conclusions Intraductal RFA can produce a typical ablation zone. The portal blood flow affects the short axial diameter of coagulation zone but does not affect the long axial diameter.

Objective:To observe the complications caused by radiofrequency ablation (RFA) after RFA via the lumen of bile duct in hilum hepatis and the pathological progress of the tissue in ablation zones. Methods: Fourteen healthy dogs were randomly divided into 2 groups with 7 dogs each group. RFA by inserting a 13 mm non-insulated mono-electrode into the lumen of bile duct was performed under general anesthesia on 10 W power output, 4 min ablation duration in group Ⅰand on 5 W power output, 8 min ablation duration in group Ⅱ. After RFA, 2 dogs were sacrificed in 3 days and 1 dog in 9 days and 4 dogs in 14 days respectively in each group. The complications concerning RFA such as bile leakage, cholelithiasis, hepatic artery thrombosis, portal vein thrombosis, hepatic vein thrombosis1 and vena cava thrombosis were observed. Results: Portal vein thrombosis, hepatic vein thrombosis and vena cava thrombosis occurred in one dog. Cholelithisis occurred in one dos. No hepatic artery thrombosis occurred in all dogs. No bile leakage caused by RFA occurred in all dogs. Obvious necrosis of the mucosal and submucosal layers of the wall of bile duct and hepatic tissue in coagulation zones occurred in 3 days after RFA. The infiltration of inflammatory cells and partial fibrosis of the mucosal and submucosal layers of bile duct and hepatic tissue occurred in 9 days after RFA. Obvious fibrosis of the wall of bile duct and hepatic tissue occurred in 14 days after RFA. Conclusions: The complications caused by RFA occur seldom after RFA via the lumen of bile duct. The necrosis, the infiltration of inflammatory cells and gradual fibrosis of the mucosal and submucosal layers of bile duct and hepatic tissue occur in ablation zone.

BACKGROUND: It is proposed that elevated serum homocysteine is an important independent risk factor for ischemic stroke (IS), and 5, 10-methylenetetrahydrofolate reductase (MTHFR) is the key enzyme for homocysteine metabolism. The relationship between genetic mutation of MTHFR and IS remains controversial.OBJECTIVE: To examine the association of hyperhomocysteinemia and two MTHFR gene polymorphisms with IS in Northwest Chinese population.DESIGN: Case-control study.SETTING: Department of Neurology, First Hospital Affiliated to Jilin University, and Department of Neurology, Xijing Hospital, Fourth Military Medical University of Chinese PLA.PARTICIPANTS: Ninety-seven consecutive patients with ischemic stroke (71 males and 26 females) treated between November 2001 and May 2002were recruited, who were diagnosed by CT scan or MRI in the Department of Neurology, Xijing Hospital, Fourth Military Medical University of Chinese PLA. The control group consisted of 94 subjects (58 males and 36 females) without history of ischemic stroke. All the subjects were free of intracranial hemorrhage, cancer, renal dysfunction, and none used multivitamins or estrogen.METHODS: Serum homocysteine was measured by fluorescence polarization immunoassay. Polymerase chain reaction-restriction length polymorphism (PCR-RFLP) method was employed to detect the genotype at the two sites of C677T and A1298C in MTHFR gene.MAIN OUTCOME MEASURES: Serum homocysteine levels and the genotypic frequency frequencies of the two mutations of MTHFR.RESULTS: The 677T allele frequency was 59.3% in IS patients and 44.7% in the controls, showing significant differences (P=0.006), but no difference in 1298C allele frequency was detected between the two groups (22.7% vs 19.7%, P ＞ 0.05). Homozygous 677TT genotype was closely associated with hyperhomocysteinemie (P ＜ 0.01). In multivariate logistic regression analysis,677T gene mutation and hyperhomocysteinemie were all associated with the IS, with an OR of 1.870 and 1.031 (P＜ 0.05), respectively.CONCLUSION: Hyperhomocysteinemie is a risk factor of IS, and C677T mutation significantly increases homocysteine levels, and serves also as an independent genetic risk factor of IS.

Objective To investigate the clinical value of lasting methylene blue staining in precise hepatectomy.Methods The clinical data of 21 patients with liver cancer who received precise hepatectomy after methylene blue staining at General Hospital of PLA from February to August in 2009 were retrospectively analyzed.After the hepatic pedicle Was dissected,methylene blue WaS injected into the portal vein,and then the hepatic pedicle was ligated.Parenchymal division is initiated along the line of devascularization demarcated on Glisson capsule.Results The success rate of methylene blue staining Was 100%.Methylene blue retained in the parenchyma for(80±23)minutes.Right hepatectomy was performed on 2 patients,left hepatectomy on 1,right posterior lobectomy on 2,right anterior lobectomy on 3,left lateral lobectomy on 1,segmentectomy of segment Ⅷon 2,segmentectomy of segment Ⅶ on 3,segmentectomy of segment Ⅵ on 1,segmentectomy of segment Ⅳ on 2 and combined segmentectomy on 4.The mean volume of blood loss,incidence of postoperative complications and postoperative hospital stay were(236±6)ml,14%(3/21)and(12±3)days.Conclusions Ligation of hepatic pedicle after methylene blue injection has the advantages of high success rate and lasting staining of parenchyma of liver.Especially,this staining method contributes to improve the precision of hepatectomy by guiding the segment selection during parenchyma transection.

Objective To evaluate the feasibility of radical liver resection following downstaging of hepatocellular carcinoma (HCC) by transcatheter arterial chemoembolization (TACE). Methods Eleven patients with HCC underwent radical liver resection after downstaging of HCC by TACE from January 1991 to June 2002, then the clinical features, intraoperative blood loss, postoperative complications and survival time were studied. Results All patients received the radical liver resection successfully, and the mean intraoperative blood loss and operative time of all the patients Was 1336.4ml (110-3200ml) and 272.8 minutes (210-390 minutes), respectively. Each of the 6 patients had an amount of blood loss more than 1000ml. The postoperative complications included bile leakage (3 patients) and ascites (1 patient), with total incidence of 36%. The median survival time was 61.5 months, and the number of patients survived for 1, 2, 3 years was 8, 7, 6, respectively. Conclusion Radical liver resection after downstaging of HCC by TACE is safe and feasible.

Objective To investigate the effects of docosahexaenoic acid (DHA) on action potential (AP)and transient outward potassium channel (Ito) in rat ventricular myocytes in order to evaluate the anti-arrhythmia mechanism of DHA. Method The rat ventricular myocytes were isolated by using enzyme digestion method. AP and Ito of individual ventricular myocyte were recorded by using patch-clamp technique in whole-cell configuration at room temperature. The effects of DHA on AP and Ito were observed when it was applied in 0 μmol/L, 20 μmol/L, 40 μmol/L, 60 μmol/L, 80 μmol/L, 100 μmol/L and 120μmol/L separaterly. Results The 25%,50% and 90% of action potential duration (APD25, APD50 and APD90) were gradually prolonged with the escalation of concentration of DHA ( P ＜ 0.05, n= 20). The effects of DHA of different concentrations on AP maximal velocity (Vmax), AP amplitude (APA) and AP overshoot (OS) did not produce significantly different results (P ＞ 0.05, n= 20). The degree of blockade of Ito was concentration-dependent as different concentrations of DHA were applied, and as the concentration of DHA was escalated, the I-V curves went downwards, the stably inactivated curves shifted to the lift, and the time taken for recovery from inactivation prolonged ( P ＜ 0.05, n =20). However, the different concentrations of DHA did not produce different effects on stably activated curves ( P＞ 0.05). The Itos were blocked to (2.61 ± 0.26)%, (21.79±4.85)%, (63.11 ± 6.57)%, 75.52±7.26 ) %, (81.82 ± 7.63) % and (84.33 ± 8.25) % by the above given concentrations of DHA respectively under given potential equaling to + 70 mV( P ＜ 0.05, n = 20), and the half-effect concentration (EC50) of DHA on Ito was(49.11±2.68) umol/L. Conclusions The effects of DHA on APD and Ito may be one of the anti-arrhythmia mechanism of DHA.

Objective A foundation for one of the biological components,Spirulina,to be applied in Controlled Ecological Life Support System(CELSS)would be laid with exploring effects of ionization radiation on the growth of Spirulina.Methods By using the ?-rays of ~(60)Co,Spirulina were irradiated.The dose of the ionization radiation covered 0,0.5,1.0,1.5,2.0,2.5,3.0 kGy.After irradiated,these Spirulina were cultured under the same conditions.The growth state,shape change,photodensity change,photosynthetic efficiency(O2 produced),and trophic physiological indexes of Spirulina or its solution,were observed,measured and analyzed.Its anti-irradiation ability was investigated.Results After irradiared with ~(60)Co ray,the growth rate,photosynthetic O2 produced efficiency,length of fila and other trophic physiological indexes were all affected in certain degree,but as compared to the higher plants,Spirulina have stronger radiation proof and self-rehabilitation capacity.Even if under high radiation condition(3.0 kGy),there was no complete death of cells,and the dose resulted in 50% death of the Spirulina was 2.0 kGy.Conclusion Spirulina has stronger ionization radiation proof and self-rehabilitation capacity,it can be considered as one of the key biological components in CELSS for future long-term space missions.

OBJECTIVE To investigate the antibiotic resistance status in clinical strains of Staphylococcus aureus (SAU) in Xiangfan and provide scientific evidence for reasonable use of antibiotics. METHODS Retrospective review was performed to analyzed the specimen source and the clinical distribution of 359 strains of SAU. BioMerieux Vitek 32 was used to identify the species of bacteria. Antibiotic susceptibility test was performed by K-B method and drug-resistance results were read according to CLSI2006. RESULTS Isolating rate of methicillin resistant S. aureus (MRSA) arrived at 54.9%. The results of susceptibility test showed that SAU had been resistant to the diverse antibiotics in different degree. The drug sensitivity rate of glycopeptide antibiotics and linezolid were all 100%. CONCLUSIONS The different grade hospitals should practically perform the management of antibiotics to postpone the resistance development and control outbreak and prevalence of nosocomial infections.

Objective To summarize the safety and efficacy of low dose of hepatitis B immunoglobulin (HBIG) for prevention of de novo hepatitis B infection after renal transplantation.MethodsThe clinical data of 138 patients who received renal transplantation without hepatitis B infection between January 2007 and June 2010 were retrospectively studied (study group).All the patients in study group were given low dose of HBIG injection before transplantation.The HBsAb titer was monitored regularly after transplantation,and the dosage of HBIG adjusted according to the level of the HBsAb titer.HBIG was implied to all patients in the study group for more than one year.The clinical data of 196 patients who received renal transplantation without hepatitis B infection between January 2004 and December 2006 served as the control group.These 196 patients were not treated with HBIG.The incidence of de novo hepatitis B infection,and acute rejection of these two groups was analyzed.The one-year graft and patients survival rate was also investigated.Results During the follow- up period of 12 months,only one case in the study group had de novo hepatitis B infection (0.7％) 6 months after renal transplantation,while 11 cases (5.6％) in the control group had de novo hepatitis B infection,in which 2 cases were died from acute hepatic failure.The incidence of de novo hepatitis B infection had statistically difference between the two groups (P＜0.05).The incidence of acute rejection in the study and control groups was 13.8％ and 17.3％ respectively (P＞0.05).The one-year graft and patient survival rate in the study and control groups was 96.4％ and 97.8％,and 90.3％ and 91.8％ respectively (P＜0.05).ConclusionLow dose of HBIG is effective and safe for prevention of de novo hepatitis B infection after renal transplantation.

Objective To evaluate three-dimentional (3D) reconstruction technique and methylene blue staining in precise anatomic hepatectomy.Methods The clinical data of 12 patients with hepatocellular carcinoma who were admitted to the Chinese PLA General Hospital from February 2009 to August 2011 were retrospectively analyzed.The 3D reconstruction of the liver tumor and intrahepatic vessels were done based on the computed tomography data and magnetic resonance imaging data.The portal vein supplying the tumor and its anatomic relationship with adjacent vessels were evaluated.Precise anatomic hepatectomy was performed guided by sustained methylene blue staining.Results The accurate rate of 3D model of the portal triad was 12/12.The shape of target segments observed after methylene blue staining was consistent with the results of 3D evaluation.Two patients received hemihepatectomy,3 received lobectomy,5 received monosegmentectomy or subsegmentectomy,2 received multisegmentectomy.The mean tumor diameter,operation time,blood loss,postoperative hospital stay and complication rate were 5.6cm (2.5-16.0 cm),(150±24)minutes,(236±25)ml,(10±3)days and 2/12,respectively.After a median follow-up of 14 months,tumor recurrence was found in 2 patients,and 1 of them died of tumor progression.Conclusions The 3D reconstruction may contribute to precise evaluation of the anatomic relationship between the tumor and its adjacent vessels.The 3D technique combined with sustained methylene blue staining may significantly improve the accuracy of anatomic hepatectomy.