The reaction product of cerium used for. localization of 5'-nuclcotidase (5'- Nase) and p-nitrophenylphosphatase(p-NPPase) is highly electron-dense but lacks sufficient contrast at the light microscopic level. We describe two methods for converting the reaction product of cerium to colored compounds visible by light microscopy. Using the Ce-Pb method and Ce-Pb-AgS method, the reaction prod- ucts of 5'-Nase and p-NPPase in isolated neurons of frontal cortex of rabbit were visualized by light microscopy. Aftcr application of the Ce-Pb-AgS method, surface of isolated neurons exhibtied crystalline precipitates by scanning electron microscopy(SEM). X-ray microanalysis of these crystals revealed the presence of high amounts of Ce, S/Pb and Ag. These results demonstrate that enzyme activity could be verified by SEM in conjunction with elementary microprobe analysis.

Objective To compare the clinical effects of endoscopic saphenous vein harvesting and traditional surgical management in coronary artery bypass grafting(CABG).Methods Between march 2007 to June 2008,215 patients underwent CABG.Among them,87 patients underwent endoscopic saphenous vein harvesting.At the same time,128 cases were managed by traditional ways.Results The cases were foUowed up for 1-17 months.Endoscopic great saphenous vein harvesting was superior to traditional management in the healing of wound infection,relief of pain,improvement of edema and skin feeling(P＜0.05).Conclusion Endoscope saphenous vein harvesting is an efficient technique for CABG which is characterized by less trauma and fewer wound complications,and will not influcence the function of vein as well.On the other hand,the satisfaction is improved.

Objective To analyze the reasons of perioperative hypoxia in Stanford A aortic dissection,and summarize its management strategies.Methods From Dec.2005 to Jul.2011,sixty four patients underwent surgery for acute type A aortic dissection,of which 9 cases were with chronic dissection and 55 cases with emergent ones.Preoperative oxygen fraction ratio( PaO2/FiO2 )in 51 cases was lower than 200 mm Hg.All of them underwent the surgery with the help of deep hypothermia cardiac arrest technique.Results Three cases died.Thirty-three cases could not live without ventilation during the first 72 h because of continuous hypoxia ( PaO2/FiO2 ＜ 200 mm Hg).One case underwent tracheotomy and auxiliary ventilation for 9 days.The rest were live without ventilation after auxiliary ventilator for 72 - 120 hrs.The data showed that postoperative hypoxia was related to preoperative hypoxia (oxygen fraction ratio ＜ 200 mm Hg),BMI,acute onset,hypothermia cardiac arrest time,and transfusion more than 3000 ml ( P ＜ 0.05 ).Conclusion Great attention should be paid to the perioperative hypoxia-related factors in Stanford A dissection,which will be helpful to improve prognosis.

Objective To evaluate the diagnostic value of 128-slice spiral CT angiography( MSCTA)for bypass grafts in patients after coronary artery bypass grafting(CABG).Methods One hundred and thirty-three bypass grafts (44 IMA grafts,89 saphenous veins grafts) of 46 patients after CABAG operation for 12 to 76 months were examined by MSCTA.Then the coronary angiography(CAG) was performed on those patients 3 - 10 days after MSCTA examination.The MSCTA results were compared with the angiography results.Results Among the 133 bypass grafts,MACTA examination showed that 17 grafts were occluded and 20 grafts were severe restenosis( restenosis degree ＞ 50％ ).There was also 17 occluded grafts showed in CAG examination as in MSCTA results.But 21 restenosis ( restenosis degree ＞ 50％ ) bypass grafts were identified by CAG.Compared with the CAG results,there was 1 false positive and 2 false negative in the MSCTA results.The overall sensitivity and specificity of MSCTA on evaluating the bypass grafts were 94.7％ and 98.9％.The positive predictive value and the negative predictive value were 97.3％ and 97.9％,respectively.Conclusion As a noninvasive examination,128-slice spiral CT could accurately identify and evaluate the bypass grafts lesions after CABG.

Objective To summarize the experience in endovascular repair of De Bakey type Ⅲ aortic dissection in recent years and summarize the prevention and management of the related perioperative complications.Methods From January 2009 to January 2011,49 cases of endovascular repair for De Bakey type Ⅲ aortic dissection were performed under general anesthesia in our department.There were 45 male and 4 female.The follow-up was performed in the outpatient department or by telephone.Results There was no inhospital death and no paraplegia events.Severe complication included:coma,2 cases ( 4.1％ ) ; endoleak,2 cases (4.1％ ) ; upper limb ischemia,2 cases (4.1％ ).Recurrent proximal aortic dissection,1 case.Fever was occurred in most of those cases.Conclusion Endovascular repair of aortic dissection improves the outcome of aortic dissection patients.But more attention should be pay to prevent the severe complications,It will help to improve the prognosis and life quality by reducing the risk of retrograde dissection,acute brain ischemia and endoleak.

Objective To review the experience of treatment for prosthetic valve endocarditis(PVE)after mitral valve replacement(MVR)in 16 cases.Methods From September 1979 to December 2010,16 patients were diagnosed as PVE after MVR by modified Duke University diagnostic criteria.There were 10 males and 6 females.Their ages ranged from 19 to 55 years old(mean 28 years old).The incidence of PVE was 0.97％(16/1657)after MVR.Blood culture positive was in 5 cases.Medical treatment alone was performed in 10 patients who were treated by using Penicillin or Vancomycin with other broad-spectrum antibiotics,using Fluconazole and Amphotericin if necessary.Combined medical and surgical management were performed in 6 cases.One emergency case was operated because of obstinate heart failure.Five cases underwent operation after adequate antibiotics treatment and general condition improvement.The infective tissue and vegetation were aggressively debrided after the infective prosthetic valve removed.Before the new valve was replaced paravalvular tissue must be flushed with diluted iodine solution and large quantities of normal saline.Tricuspid valve repair (TVR)was performed during the same period in 3 cases.Results Hospital death occurred in 8 patients and only 2 patients were recovery in group with medical treatment only.The main reasons of death were infective shock and cardiac failure in 4 patients,cerebral complications(embolism or bleeding)and multiple organs failure in 4 cases.While 6 patients cured after combined medical and surgical management.Follow-up had been carried out in 8 cases for 1.7 to 15 years(mean 5.1 years).Eight years later one patient was re-operated because of severe tricuspid regurgitation and paravalvular leak.There was no PVE recurrence in others.Conclusion Combined medical and surgical management for PVE get a better result than medical treatment alone.Good prognosis lies in timely diagnosis,adequate antibiotics,aggressive debridement of infective tissue and better myocardium protection during operation.

Objective To summarize our experience in endovascular repair of 83 cases with type B aortic dissection.Methods A retrospective analysis was performed in 83 cases of type B aortic dissections who were treated in our hospital.Results The surgical procedure was successful for all the patients.Two patients died peri-operatively.One case encountered a coma,but no post-operative paraplegia occurred.Conclusion Endovascular repair for type B aortic dissection is a micro-invasive,safe and effective technique.Long-term follow-up is required to give a comprehensive evaluation.

Objective To describe the treatment experience of post-operative complications after total arch replacement for acute type A aortic dissection in 34 cases.Methods The subjects were 34 consecutive patients (Twenty-eight males and 6 females,age 34.0 -60.0 yrs) who received total arch replacement for acute Stanford type A aortic dissection from Jan.2005 to Oct.2010 in our hospital.The duration from the onset of the symptoms to the hospitalization ranged from 4 - 18 hrs.Pre-operative 2-D Echo revealed aortic valve regurgitation in 8 patients and mitral valve regurgitation in 1 patient.Results Three patients died after operation ( mortality 8.8％ ).Severe complications included acute kidney injury in 13 cases,respiratory dysfunction in 12 cases,paraplegia in 1 case,mental disorder in 10 cases and excessive post-operative bleeding in 2 cases.Conclusion The incidence of the complications after total arch replacement is still high and severe.Intensive care should be stressed peri-operatively and early diagnosis and treatment for post-operative complications are important procedures.

Objective To summarize our experience in the management of cardiopulmonary bypass (CPB) with deep hypothermic circulatory arrest (DHCA) during aortic arch surgery.Methods From March 2007 to May 2010,58 consecutive patients,including 24 urgent and 34 selective operations underwent aortic arch surgery.Thirty-nine hemiarch and 19 total aortic arch replacement operations were performed.CPB was established by perfusion through femoral artery (42 cases) and right subclavian artery (RSA) ( 16 cases),of which 4 cases were carried out with antegrade cerebral perfusion (ACP).Results The mean CPB time was ( 208.88 ± 136.45 ) min.The mean cerebral circulation arrest was ( 27.36 ± 11.50 ) min.Nasopharyngeal and rectal temperature were ( 16.01 ±2.67)℃ and ( 19.72 ±2.13)℃ respectively before DHCA was initiated.The mean times for cooling and rewarming were ( 50.91 ± 16.89) min and ( 88.97 ± 43.68 ) min.The mean time of intubation was (56.70 ± 45.19 ) h.The time in ICU was ( 5.68 ± 5.31 ) d,and the time of hospitalization was (30.11 ± 22.27 ) d.Acute renal failure,hypoxemia,and paraplegia occurred post-operatively in 4,19,and 2 patients,respectively.Four patients died post-operatively with a mortality of 6.90％.Compared with those received hemiarch replacement operation,the patients received total aortic arch replacement had statistically longer time of CPB([262.16 ±219.97]min vs [182.92 ±53.81] min,t =2.14,P ＜0.05),cerebral circulatory arrest ( [30.47 ± 15.86 ] win vs [25.85 ± 8.48 ] min,t =2.40,P ＜ 0.05 ),rewarming ( [110.00 ± 68.66 ] min vs [78.72 ± 17.31 ] min,t =2.69,P ＜ 0.05 ),and intubation ( [93.95 ± 131.89 ] h vs [38.08 ± 30.70 ] h,t =2.50,P ＜ 0.05 ).There was no significant difference in the times of these procedures between emergency surgery group and elective surgery group,between RSA and femoral artery cannulation groups.Conclusion It is crucial that the cooling and re-warming procedures during aortic arch surgery should be carried out slowly,gradually,and completely when DHCA was adopted alone.conclusion through right axillary artery or RSA was preferred for ACP,in order to accomplish the body circulation arrest at a relative high temperature,to shorten the CPB time,and to alleviate potential harmful effects of hypothermia.Meticulous management of CPB is one of the most important measures to improve the patients' outcome.

Objective To describe the follow-up data of 34 patients receiving total arch replacement with an open stent graft for acute type Ⅰ aortic dissection.Methods The subjects were 34 consecutive patients with type Ⅰ acute aortic dissection ( Twenty-eight males and 6 females,aged 34.0 - 46.0 yrs) who received total arch replacement with an open stent graft in our hospital from Jan.2005 to Oct.2010.Thirty of the 34 patients were followed up for 2 - 70 months.CT scanning was performed at the 3 and 12 months and then yearly after operation to detect the thrombus formation,absorption of thrombus,and obliteration of the false lumen after its exclusion by the stent graft.Results Three patients died peri-operatively with the mortality of 8.8％.One patient died during the follow-up period.Obliteration was recognized in all the patients at the distal side of the stent graft during the follow-up period.The false lumen remained in 10 patients at the distal part of descending aorta,but the diameter of the false lumen was not enlarged.Conclusion In patients with acute type Ⅰ aortic dissection,it is relative safe to perform extensive primary repair of the thoracic aorta by stent grafting.This method may enhance the obliteration of the false lumen and reduce the possibility for further operations to manage a residual false lumen.