Plasma heparin activity dextran

Dextran 70 seems to be as effective as subcutaneous heparin, but is easier to administer and puts less of a burden on nursing services. Measured blood loss is similar in patients given dextran, low-dose heparin or pre-operative warfarin. Few patients given dextran or low-dose heparin seem to bleed excessively. In one study, bleeding was associated with higher levels of plasma-heparin activity (30 ). 

Specihc poly anions such as dextran sulfate (DS) appear to exhibit strong anti-HIV activity in vitro [36,37]. Human oral administration of DS is poorly absorbed, but intravaneous administration does result in increased plasma lipolytic activity [38]. Poly anions that have been considered for intravaginal anti-HIV activity include DS, carrageenan, heparin, heparan sulfate, dermatan sulfate, pentosan polysulfate, fucoidan chondroitin sulfate, keratan sulfate, and PAVAS [21,22,39,40],... 

Anticoagulant activity in vitro calculated from the number of micrograms of dextran sulphate and heparin required to give 50 per cent inhibition of coagulation of 1 ml. dog plasma. Anticoagulant activity in vivo calculated from Lee and White clotting times at 0, 1, 2, 3 hours after intravenous injection in rabbits of 3 mg/kg. Peak = peak clotting times. Area = area under the curve with formula of Millar, Jaques and Henriet suitably modified. Values for heparin were activity in vitro, 3-5 g in vivo, peak = 100 (92-108) minutes area = 0-20 LDg = 220 42 mg/kg. 

Payne and Baker tested a series of sulphated dextrans in vitro and in vivo. Their data have been recalculated and are shown in Table 3.8. In vitro, the anticoagulant activity in citrated plasma was from 0-09 to 20 per cent of that of heparin. For different preparations the value varied according to whether the end-point was the maximum amount which allowed clotting, or the amount for 50 per cent clotting or the minimum amount to prevent clotting completely. In contrast to the low anticoagulant potency in vitro are the results obtained in vivo. When the total response measured by the Lee and... 

The role of sialic acid residues in determining the life-time of circulating cells and glycoproteins and the importance of desialylation have been discussed, Chromatography on Blue Dextran 2000 coupled to agarose has been used in the rapid separation of factor X from citrated human plasma a 2(XX)-fold purification was achieved, Inhibition by the antithrombin-heparin cofactor of the conversion of factor IX into its active form by factor IXa has been examined. The process is time-dependent and requires a 1 1 combination... 

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