Thrombin clots

In essence, the basic steps of making cell blocks consist of fixation, centrifugation to make cell pellet, transfer the pellet to a labeled tissue cassette which then is processed and embedded in paraffin. The most challenging component of this technique is the methods to harden the cell pellet so it can be easily picked up from the tube without losing precious material. With only a simple sedimentation technique, the cell pellet is usually small and friable. In order to harden the cell pellet, several technical modifications have been reported. The most popular methodology includes plasma-thrombin clot technique, agar technique, and fixation with Bouin s solution. 

These authors reported greatly improved sample transfer without pipette failure due to plugging caused by thrombin clot formation when a LEAP HTS PAL autosampler was used for liquid transfer automation. 

The anticoagulant activity of dextran derivatives were assessed by measuring the thrombin clotting time (ThNIH units) of freshly prepared platelets from plasma in the presence of the CMD, CMDB, CMDBSSu and CMDSu polymers and of human thrombin (1094 NIH units mL 1). The anticomplementary activity was expressed as the amount of polymer that inhibits 50% formation of the alternative and classical pathway C3 convertase [220,290,291]. 

Thrombin clotting time 70 to 120 seconds 1 50 to 600 seconds depending on indication for anticoagulation... 

We now report results concerning the interactions between these two proteins and two of these polystyrene derivatives sulfonated polystyrene (PSSO3) and sulfonate-glutamic acid sulfonamide polystyrene (PSSO2GIU). The adsorption of each protein was studied either in purified system or in plasma and the binding constants were determined. Moreover, the catalysed formation of thrombin-anti-thrombin III complex was examined and compared with the antithrombic activity measured through thrombin clotting times of plasma preincubated with these polymers. 

The antithrombic activity of the polymers was first compared through the thrombin clotting times of platelet poor plasma (PPP) incubated with various amounts of suspended resin. The results were translated into the amount of inactivated thrombin as previously described and are reported in Fig. 4. These curves show that the inactivation of the same thrombin activity in plasma requires approximately 3 times more PSSO3 than PSSO2GIU. 

Prothrombin time (PT), activated partial thromboplastin time (aPTT), and Thrombin clotting time (TCT)... 

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