Optimization of von Willebrand factor multimer analysis in vertical mini-gel electrophoresis systems: A rapid procedure.

Von Willebrand disease (VWD) is a common cause of bleeding worldwide. Analysis of von Willebrand factor (VWF) multimer distribution (VWF:MD) is essential to properly classify and treat different types of VWD, and it is performed using a SDS agarose gel electrophoresis followed by Western blotting, a handmade technique that demands days to be completed and requires skillful execution. Aiming both to facilitate gel production and to shorten the preparation time, we developed an uncomplicated technique to provide agility in the analysis of VWF:MD, so that it can be easily accomplished in the routine practice of hemostasis laboratories.

Markers of endothelial dysfunction and severity of hypoxaemia in the Eisenmenger syndrome.

Endothelial dysfunction has been reported in hypoxaemic patients with the Eisenmenger syndrome, but a direct correlation between levels of endothelial markers and the severity of hypoxaemia has not been explored. With this in mind, we compared the levels in the plasma of tissue-type plasminogen activator, thrombomodulin, and von Willebrand factor in 25 patients with the Eisenmenger syndrome. They had a median age of 31 years, and were divided into 2 groups according to their recent clinical history.

Hypoxia and altered platelet behavior influence von Willebrand factor multimeric composition in secondary pulmonary hypertension.

In pulmonary hypertension (PH), defective plasma von Willebrand factor (vWF) lacking the larger multimers with increased concentration of low-molecular-weight fractions (LMW) has been reported, although the mechanisms involved are not completely known. Altered platelet behavior may be involved in this alteration; this hypothesis was investigated in 10 patients with PH associated with chronic hypoxemia and erythrocytosis (age 13 to 51 years, mean pulmonary artery pressure 38 to 98 mmHg). The possible influence of the hematocrit (Hct) and decreased oxygen saturation (SpO2) on vWF abnormalities was examined.