ABSTRACT
Objective: To study the effect of serum from patients with atherosclerotic risk factors on the synthesis of endothelial tissue factor. Methods: Serum from 30 diabetic patients, 30 hyperlipemic patients, 30 smokers and 30 normal serum were incubated with cultured endothelial cells from a human umbilical vein. The tissue factor of endothelial cells was measured using the assay that was developed in house after 24 hours incubation time. Results: Smokers’ serum can significantly cause the increase in endothelial tissue factor. The mean level of tissue factor induced by smokers’ serum is 1.12 microunits/cell whereas the mean level of tissue factor induced by diabetic serum, hyperlipemic serum and normal serum is 0.4, 0.48 and 0.2 microunit/cell, respectively. Conclusion: Smoking may increase the risk of thrombosis by increasing the tissue factor production of endothelial cells.
ABSTRACT
Home-made enzyme-linked immunosorbent assays (ELISA) for protein C (PC) and protein S (PS) antigenic assays, using commercial antibodies, were set up in our laboratory. The latter can be used for the measurement of total PS and also free PS, after the precipitation of bound form. Here we describe the procedure for both PC and PS ELISA's, and their quality evaluation and cost. Intra- and inter-assay variation (n = 20) were calculated to be 7.3% and 8.1% for the PC ELISA and 10.2% and 10.1% for free PS ELISA. The accuracy of the tests assessed by external quality assurance of WHO International External Quality Assessment Scheme in Blood Coagulation (IEQAS) was satisfactory. The level of PC antigen in 50 healthy volunteers was 89 ฑ 18% and that of free protein S was 94 ฑ 16%. In conclusion the quality of the home-made ELISA's was acceptable while the cost was much cheaper than that of commercial ELISA kits.
ABSTRACT
Plasma levels of von Willebrand factor (vWF), an indicator for endothelial injury, were measured in type II diabetic patients with or without retinopathy and 20 normal control subjects. Patients were grouped according to their degree of retinopathy, 12 patients with no evidence of retinopathy, 19 patients with background retinopathy and 23 patients with proliferative retinopathy. All groups of diabetic patients had significantly higher vWF levels when compared to normal controls. But the levels of vWF did not correlate with the severity of retinopathy. The data suggested that diabetic patients had some degree of endothelial injury that might not relate to the development of retinopathy.
ABSTRACT
A technique to measure the tissue factor activity of endothelial cells was developed and the tissue factor activity of the endothelial cells was studied after stimulation with cultured media from the endothelial cells of babies born to severe per-eclampsia patients and from normal pregnancies. The results show no statistical differences. Media from the endothelial cells of the babies of pre-eclampsia patients induced the tissue factor activity to a mean level of 0.08 mU/ml, whereas that from the normal pregnancies stimulated the tissue factor synthesis to a mean level of 0.14 mU/ml. It may be concluded that there are no injurious substances released from the endothelial cells of babies that cause increased tissue factor synthesis from endothelial cells.
ABSTRACT
D-dimer was measured in 20 normal non-pregnant women, 20 normal pregnant women and 20 severe pre-eclampsia patients. D-dimer was found to be 182 + 63 ng/ml (mean+ SD) in non-pregnant women, significantly higher at 1,355+ 279 ng/ml in normal pregnant women and 1,928+ 625 ng/ml in severe pre-eclampsia. No abnormalities were detected in a screening coagulogram. It is concluded that D-dimer may-be more useful than a screening coagulogram. For the early detection of the activation of the coagulation system that occurs in normal pregnancy and becomes elevated in severe pre-eclampsia.