[Relationship between PDGF-A, bFGF and proliferation of smooth muscle cells in vein grafts]

OBJECTIVE

To detect the relationship between platelet-derived growth factor-A (PDGF-A), basic fibroblast growth factor (bFGF), and proliferation of smooth muscle cells in vein grafts.

METHODS

An animal model of autogenous vein graft was established by transplanting internal branch of the jugular vein to the common iliac artery by end-to-end anastomosis. 25 rats were used. The grafted veins were harvested at 6 h, 2 d, 1 w, 2 w and 4 w respectively after the operation. The expression of PDGF-A and bFGF in different stages after grafting procedure was observed immunohistochemically.

RESULTS

The expression of PDGF-A peaked at 1 w, paralleled with proliferation of SMC, and was significantly higher than that at 6 h (P < 0.01). The expression of PDGF-A diminished gradually. At 4 w, it was significantly lower than that at 1 w (P < 0.01). bFGF demonstrated bimodal pattern of the expression: the first peak of expression occurred by 2 d and the second peak by 2 w. The difference was significantly compared with other stages.

CONCLUSIONS

The expression of PDGF-A 1 contributed to migration and proliferation of SMC. Except for contributing to proliferation of SMC, bFGF perhaps took part in endothelization.

[The relation-ship between apoptosis, apoptosis related-gene expression and proliferative activity in smooth muscle cell after autogenous vein grafting]

OBJECTIVE

To study the mechanism of graft vein stenosis.

METHODS

A rat experimental model of autogenous vein graft was established by transplanting the right external jungular vein into the infrarenal abdominal aorta in 100 Wister rats. Electric microscope, TUNEL and immunohistochemical S-P technique were used to detect the apoptosis, the expression of apoptosis related-gene bcl-2 and bax and proliferation cell nuclear antigen (PCNA) of smooth muscle cells(SMCs) in vein graft.

RESULTS

From 1 to 8 weeks after replacement, the expression of apoptosis and PCNA of SMCs was continuously higher than the control group (P < 0.01). From 1 to 2 weeks, the expression of TUNEL and PCNA showed peak value. From 1 to 2 weeks, the positive rate of apoptosis was lower than that of PCNA, but from 4 to 8 weeks, the positive rate of TUNEL was higher than that of PCNA. There was obvious positive correlation between the expression of TUNEL and PCNA (r = 0.813 P < 0.05). One to 2 weeks after vein grafting, bcl-2 positive rate increased and was more different than the control group and the group of 4 to 8 weeks after vein grafting (P < 0.010).

CONCLUSIONS

The imbalance of proliferation and apoptosis may be related to the vessel remodeling and vein graft stenosis, and bcl-2 and bax protein may involve in the regulation of apoptosis of VSMC. Adopting the mixed strategy to regulate the balance between proliferation and apoptosis may be useful to prevent vein graft stenosis.

[Reconstruction of esophagus by microsurgical technique in forty-five cases]

Reconstruction and repair of atresia or defect of the upper portion of esophagus is difficult. From November 1980 to December 1997, forth-five cases, consisting 35 males and 10 females, were treated with microsurgical technique. The 45 patients fell into the following groups as esophageal atresia of various causes in 21 cases, anastomotic fistula or stenosis following reconstruction of esophagus in 7 cases and late carcinoma of esophagus in 17 cases. The types of reconstruction consisted of transfer of free jejunum with its lower portion carrying a vascular pedicle in 24 cases, free transfer of jejunal graft in 15 cases, free vascularized jejunal graft in 2 cases and free vascularized tubular skin graft in 4 cases. After a follow-up of 6-19 months besides eight cases died from late esophageal carcinoma, thirty-seven cases were survived and could take food by mouth. All of the benign cases could return to work. In patients having late esophageal carcinoma, the operative procedure could improve the life quality and facilitate chemotherapy and radiotherapy.

[Management of true extremity aneurysms: experience in 23 patients]

OBJECTIVE

To explore the etiologic feature and specificity of diagnosis and treatment in true aneurysms of the extremities.

METHOD

23 patients with true aneurysms of the extremities from January 1984 to September 1997 were retrospectively reviewed.

RESULT

Of 30 true aneurysms of the extremities, multiple aneurysms were found in 7 patients (30.4%). The multiple aneurysms were diagnosed in the same time or in different time. 21 patients were treated by exclusion of aneurysm and replacement with autogenous saphenous vein or graft.

CONCLUSION

Early diagnosis and treatment are recommended to prevent complications which can cause limb loss, and multiple aneurysms must be taken into account. Importance of arteriography should be stressed in the diagnosis of multiple aneurysms. Exclusion of aneurysm and autogenous saphenous vein reconstruction is the first choice of treatment, circulation of the operated extremities should be noticed and close follow-up is imperative to pay attention to the development of new aneurysms.

[Surgical treatment of extracranial carotid artery aneurysm]

OBJECTIVE

To study the experience in the treatment of extracranial carotid aneurysm.

METHODS

67 cases of extracranial carotid artery aneurysm(ECAA) were treated surgically from January 1986 to June 1997.

RESULTS

There were a mortality rate of 1.5% and a hemiparalysis rate of 4.5%.

CONCLUSION

Clinical examinations are important for diagnosis of ECAA. Angiography plays a significant role in understanding the morphology, function, pathophysiology of ECAA. To decrease postoperative cerebral ischemia, collateral circulation of cerebral vessels should be evaluated and matas test done. Correct operative method is a key factor for successfull treatment.

[Ultrasonic angiography in therapeutic decision-making in peripheral occlusive vascular diseases]

OBJECTIVE

To study quickscan (QS) in different therapeutic decision-making in 55 patients with peripheral occlusive vascular diseases.

METHODS

Based on QS results, 30 patients were treated conservatively. The disease progress and therapeutic effects were assessed by QS in every three months. Percutaneous transluminal angioplasty was performed successfully in 5 patients without prior diagnostic angiography. 20 patients were scheduled for surgery. Operation of eleven patients was guided by information obtained from QS findings only, which was confirmed during operation. Angiography was necessary in 9 patients except one to formulate a therapeutic strategy.

RESULTS

The accuracy of QS was 92%(23/25).

CONCLUSION

QS is of value in deciding the access route of angiography and PTA, and can replace preoperative angiography, Quickscan is time-saving, inexpensive, objective and accurate. It can be used in therapeutic decision making in peripheral occlusive vascular diseases and bypass grafting.

The accuracy of color Doppler flow imaging for the detection of symptomatic deep venous thrombosis in Chinese patients

To evaluate the ability of color Doppler flow imaging (CDFI) to detect deep venous thrombosis (DVT), which is difficult to diagnose clinically, 67 limbs of 60 patients who presented with clinical signs strongly indicative of DVT during the period between June 1988 and June 1992, were examined. The iliac, common femoral, and superficial femoral veins were assessed with the patient in the supine position, and the popliteal vein was examined with the patient prone. Gentle but firm compression with the transducer probe was used to test for the presence of DVT. Ascending contrast venograms were also obtained within 24 h after the ultrasound procedure, with venography being used as the standard for comparison with CDFI. DVT was identified in 63 limbs by contrast venography and in 62 limbs by CDFI. The sensitivity and specificity of CDFI were 98.4% and 100%, respectively, while the positive and negative predictive values were 100% and 80%, respectively. The thromboses were classified into three patterns: the filling type, the local type, and mural thrombus, detected in 63%, 27%, and 10%, of the limbs respectively, with the filling type being the most common in this series. The results of our study illustrated that CDFI is highly sensitive and specific for detecting symptomatic DVT and that it should be gradually substituted for venography in such patients.

Experience in prevention of serious complications of laparoscopic cholecystectomy

OBJECTIVE

To study the causes and prevention of the complications of laparoscopic cholecystectomy (LC).

PATIENTS AND METHODS

Based on experience with 2 428 cases, the following should be paid attention to when dissecting and separating adhesions around the gallbladder and of the Calot's triangle. The best method for the prevention of mistaking the common bile duct (CBD) for the cystic duct is to find the junction of the cystic infundibulum and duct, separate the gallbladder wall along the infundibulum, and transect the cystic duct at the junction with the infundibulum. If dense adhesions around the gallbladder or of the Calot's triangle are met with, LC should be abandoned and open the cholecystectomy (OC) should be used instead. In separating the Calot's triangle, blunt dissection should be used to avoid burning the extrahepatic bile duct (EHBD), and blind hemostasis should be avoided. If the cystic artery lies in the upper part and the back of the cystic duct, the cystic duct should be dissected out, clipped and cut first, then the cystic artery be dealt with. If the cystic artery is in the front part of the pedicle of the gallbladder, the artery should be separated, clipped and cut first. Injury to the adjacent organs may be avoided by using electric coagulating hook correctly and avoiding accidental damage to the viscera, and keeping from viscera injury due to current chemotaxis in the closed cavity of the body.

RESULTS

A total of 2427 patients were cured. One patient died of frequent episodes of supraventricular tachycardia and pneumonia on the 21st day after LC.

CONCLUSION

If LC surgeons follow the above said principles of LC technique. LC is very safe for patients with benign diseases of the gallbladder.

[Ultrasonic angiography in diagnosis of peripheral vascular disease]

The ability of Quickscan (QS) was studied to assess haemodynamically significant lesions in the iliac and femoro-popliteal arteries. Quickscan was prospectively and independently compared to digital subtraction angiography (DSA) of the iliac and femoro-poplited arteries. In 155 patients, 631 arterial segments were evaluated. A QS frequency ratio of greater than 1:3 had a sensitivity of 93% and a specificity of 85% in detecting stenosis > 50% diameter (75% area) reduction in the iliac artery as shown on DSA. The sensitivity and specificity for stenosis in the femoral and popliteal arteries were 85%, 96%, 82%, 98% respectively. In the detection of occlusion, QS had a sensitivity of 84% and a specifity of 98% in the iliac artery; 94%, 97%, in the femoral; and 94%, 85% in the popliteal arteries respectively. There was a significant correlation between the area reduction found by QS and the calf/brachial pressure index (CBI) (r = -0.77 P < 0.01). 35 patients underwent successfully angioplasty based on QS findings. We conclude that quickscan can provide an inexpensive, quick and noninvasive screening technique for the routine initial assessment of peripheral vascular disease.

A two-year experience with laparoscopic cholecystectomy--a report of 1475 cases from Kunming, China

Over a 2-year period, from 12 September 1991 to 11 September 1993, laparoscopic cholecystectomy was performed on 1475 patients with benign gallbladder disease in Kunming General Hospital, Yunnan, China. Of these, 28 cases (1.9%) were converted to open surgery. Various complications were documented in 27 instances including extrahepatic bile duct injury in 4 cases (0.3%), postoperative haemorrhage requiring laparotomy in 3 cases (0.2%) and bile leak from cystic duct stump in 1 case (0.07%). There was 1 (0.07%) death in the series. The junction between the gallbladder infundibulum and the cystic duct is an important landmark which laparoscopic surgeons must identify in the course of the procedure. Because the junction remains a comparatively constant landmark, in difficult laparoscopic cholecystectomy, excessive dissection of the bile duct would be unnecessary. During dissection of the hepatic hilus, blund dissection is recommended and the blind use of cautery and haemostasis should be avoided.

Purification and characterization of hedgehog liver metallothioneins

Two forms of liver metallothioneins (MTs) were purified from hedgehog exposed to zinc, using gel filtration on Sephacryl S-100 and DEAE Sepharose Fast Flow chromatography. The peptide chain weight of both MT-1 and MT-2 was found to be about 10,000, as determined by high performance liquid chromatography. This value was higher than that calculated from amino acid analysis. The amino acid composition of hedgehog liver MT-1 and MT-2 resembles that of liver to MTs from rabbit and other species. Their distinctive features include an extremely high cysteine content, about 33% of all the amino acid residues, and an absence of aromatic amino acids and histidine. In addition, a rapid method for the determination of MTs during animal tissue purification has been established. The samples were directly added in an ammoniacal solution of a Co(II) salt for recording linear sweep polarograms. By comparison with the commonly used metal determination method, our method is direct, rapid, credible and suitable for all the MTs or MT-like samples.

[Acute toxicity of flesh oil of Hippophae rhamnoides L. and its protection against experimental hepatic injury]

Protection by flesh oil of Hippophae rhamnoides against hepatotoxicity induced by CCl4 and acetaminophen (AAP) is reported in this paper. It was found that the oil markedly inhibited MDA formation of liver induced by CCl4 and AAP, decreased sGPT levels induced by CCl4 and blocked depletion of GSH damaged liver induced by AAP.LD50 greater than 45.0 g/kg.