The authors experienced a case of fatal cerebellar, and brainstem infarction accompanying clamping of the left subclavian artery during operation for thoracic aortic aneurysm. Autopsy of this case revealed that right vertebral artery became markedly hypoplastic distal to the posteroinferior cere bellar artery, and left vertebral and basilar arteries were occluded by thrombus formation. These findings indicate that clamping of the dominant left subclavian artery is responsible for severe vertebrobasilar ischemia producing the fatal brain infarction. Since the occurrence of this devastating complication, we have performed pancerebral angiography and balloon occlusion test of the left subclavian artery in patients who might undergo proximal clamping of the aortic arch between the left carotid artery and the left subclavian artery during operations for thoracic aortic aneurysm. Selective perfusion of the left subclavian artery is then planned for those with abnormal vertebrobasilar communications producing neurological signs.

Left ventricular hypertrophy in patients with aortic valve disease has long been recognized as a significant risk factor for aortic valve replacement. Higher operative mortality in such patients has been attributed to poor myocardial preservation. In these patients improvement of left ventricular subendocardial blood flow during reperfusion seems to be mandatory to avoid subendocardial injury. Therefore, we attempted to increase subendocardial blood flow during reperfusion by terminal warm blood cardioplegia (TWBCP) followed by controlled aortic root reperfusion (CARR) in patients requiring isolated aortic valve replacement. The patients with TWBCP and CARR had a tendency towards severe left ventricular hypertrophy and more advanced NYHA function class compared to those with hypothermic cardioplegia alone. Nevertheless, the patients with TWBCP and CARR showed significantly better recovery of left ventricular function, i.e., spontaneous recovery of beating and higher cardiac index as well as left ventricular stroke work index, despite significantly less catecholamine support. These resuls suggest that TWBCP followed by CARR may offer significant benefits over unmodified reperfusion during aortic valve replacement for patients with severe left ventricular hypertrophy.

BACKGROUNDThe earthworm fibrinolytic enzyme (EFE) is a complex protein enzyme that is widely distributed in the earthworm's digestive cavity. Possessing strong protein hydrolysis activity, EFE not only has a direct effect on fibrin, but also can activate plasminogen. Its therapeutic and preventative effects on thrombosis-related disease have been confirmed clinically. Recently, there has been increased interest in the anti-tumor activity of EFE. In this study, the anti-tumor activity of EFE, isolated from Eisenia foetida, on human hepatoma cells was evaluated in vitro and in vivo. The potential mechanisms involved were also studied.

METHODSIn vitro experiments were performed in four human hepatoma cell lines: HLE, Huh7, PLC/PRF/5 and HepG2. After treatment with EFE in various concentrations, the inhibition of the rate of cell proliferation was measured. For the in vivo studies, tumor-bearing models xenografted with Huh7 cells were developed in nude mice, and then the mice were fed with EFE once a day for 4 weeks, and the control group received only saline. An inhibitory effect on tumor growth was observed. Also, apoptosis was observed with flow cytometric assay and fluorescent dye staining with acridine orange and ethidium bromide (AO/EB). The expression of matrix metalloproteinase 2 (MMP-2) were detected by Western blotting assay.

RESULTSAfter treatment with various concentrations of EFE, the proliferation of all hepatoma cell lines was suppressed to varying degrees in vitro. The IC(50) for HLE, Huh7, PLC/PCF/5 and HepG2 were 2.11, 5.87, 25.29 and 17.30 uku/ml, respectively. After administration of EFE orally for 4 weeks, the growth of tumor xenograft of Huh7 cells in nude mice was significantly inhibited in vivo. The tumor inhibitory rates in the EFE 500 uku/(kgxd) and 1000 uku/(kgxd) groups were 46.08% (compared with control group, P = 0.026) and 57.52% (compared with control group, P = 0.002) respectively. Meanwhile, the average weight of body, spleen or thymus did not show any remarkable differences among the various groups. The population in sub-G(1) stage was more in the EFE treated groups than in the control group according to flow cytometric assay. After treatment with EFE 0, 5, 10 uku/ml for 72 hours, the apoptotic rates were 3.5%, 10.9% and 12.3% in HLE cells, and 5.0%, 24.7% and 34.5% in Huh7 cells respectively. Under fluorescent staining with AO/EB, the apoptotic morphological changes could be detected more significantly in the EFE treated groups than in the untreated groups. After treatment with EFE in doses of 0, 5, 10 uku/ml for 72 hours, the apoptotic rates were 3.02%, 8.76%, 10.54% in HLE cells, and 3.95%, 18.27%, 30.89% in Huh7 cells respectively. The apoptosis-inducing effects of EFE occurred in a dose dependent manner. Western blotting assay showed that, after treatment with EFE, the secretions of MMP-2 were significantly inhibited in HLE and Huh7 cells.

CONCLUSIONSEFE showed significant anti-tumor activity in hepatoma cells both in vitro and in vivo, which may be because EFE could induce apoptosis of hepatoma cells and inhibit the expression of MMP-2. This suggests that EFE has a potential role in the treatment of hepatoma.

Animals ; Antineoplastic Agents ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Fibrinolytic Agents ; pharmacology ; Flow Cytometry ; Humans ; Liver Neoplasms, Experimental ; drug therapy ; pathology ; Male ; Matrix Metalloproteinase 2 ; analysis ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Oligochaeta ; enzymology ; Transplantation, Heterologous