ABSTRACT
This study examined the changes of activities of vitamin K-dependent clotting factors (VKDCF)under various pathological conditions and explored the relationship between acquired deficiency of VKDCFs and hemorrhage.Clinical data of 35 patients who were diagnosed as having acquired deficiency of VKDCF were retrospectively analyzed.Coagulation factors involved in the intrinsic and extrinsic pathways were detected in these patients and 41 control subjects.The results showed that the average activities of VKDCFs were decreased in the patients in comparison to the control subjects and significantly increased after treatment of these patients with vitamin K and blood products.Multivariate regression analysis indicated that decreased activity of VKDCF was not an independent risk factor for bleeding disorders owing to deficiency or metabolic disturbance of vitamin K.It was concluded that acquired deficiency of VKDCF occurs under a variety of pathologic conditions and is closely associated with hemorrhagic events.Administration of vitamin K and transfusion of blood products containing high concentrations of VKDCFs helps alleviate the hemorrhagic diseases.
ABSTRACT
The effects of tissue factor (TF) on doxorubicin-induced apoptosis in human neuroblas- toma were investigated. The expression of TF was examined by Western blotting. TFsiRNA-pSUPER plasmid was constructed by inserting specific 19-nt silencing sequence targeting TF gene into pSU- PER vector. Transfection of TFsiRNA-pSUPER was performed using lipofectamine2000. The cytotox- icity of doxorubicin was determined by WST assay. The activation of Caspase-3 and PARP induced by doxorubicin was tested by Western blotting. The apoptotic cells were stained by Hochest33342 and counted under fluorescence inverted microscope. It was found that human neuroblastoma cell line SK-N-MC expressed high level of TF. Knockdown of the TF expression was achieved by trans- fection of TFsiRNA-pSUPER on SK-N-MC cells in a dose-dependent manner. Inhibition of TF sig- nificantly decreased the viability of transfected SK-N-MC cells treated with different concentrations of doxorubicin. Cleavage of Caspase-3 and PARP was enhanced in transfected SK-N-MC cells with down-regulation of TF. TFsiRNA treatment significantly increased the number of apoptotic cells in transfected SK-N-MC cells as compared with those control cells (P＜0.05) when these cells were ex-posed to 1 μg/mL doxorubicin for 8 h. These results suggested that knockdown of the TF expression by specific siRNA vector could increase the cytotoxicity of doxorubicin and enhance doxorubi- cin-induced apoptosis in human nearoblastoma cells. Over-expression of TF might contribute to chemotherapy resistance in human neuroblastoma and its progression, at lest in part, by regulating doxorubicin-induced apoptosis.
ABSTRACT
To clarify the role of TAFI in hypertensive disorders in pregnancy, 22 subjects, including 10 with pre-eclampsia (PE) and 12 with gestational hypertension were examined for the levels of TAFI and thrombin-antithrombin (TAT) complex. Thirty normal pregnant women served as controls. ELISA was employed for the detection. The results showed that the TAFI antigen levels in normal pregnancy group, gestational hypertension group and PE group were (85.35±24.69)%, (99.65±18.27)%, (110.12±23.36)%; (97.06±21.40)%, (114.08±27.76)%, (125.49±24.70)%; (106.6±19.21)%, (129.2±25.07)%, (139.1±30.12)%, in the 1st, 2nd and 3rd trimester respectively. No significant differences were found between the normal pregnancy group and gestational hypertension group but significant difference existed between normal pregnancy group and PE group in each tri- mester (P<0.05). TAT complexes were significantly higher in patients with PE than that in controls (P<0.05), but no correlation was found between TAT and TAFI. It is concluded that TAFI may con- tributed to the impairment of fibrinolysis in the patients with PE and may serves as a sensitive indi- cator for PE, but it may not help in the diagnosis of the gestational hypertension.