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The clotting time of blood is a measure as to how long blood requires to transform from its liquid state to that of a solid. The final product of clotting is the production of a fibrin clot (scab), a three dimensional polymer. The body uses clotting to stop bleeding that can cause extremely fatal diseases and ultimately even death. Russell's Viper Venom (RVV) generates a procoagulant effect on both citrated whole blood (CWB) and plasma by converting Factor X to Factor Xa, resulting in a shortened clotting time. Hydrogen peroxide (H 2 O 2 ) is an oxidizer generated by the immune system. H 2 O 2 serves as the first line of defense against bacteria and viruses. This in vitro study was performed by on CWB and plasma, both individually with RVV, H 2 O 2 , and the combination of the latter two. The clotting time, rate of clot formation, and the maximum strength of the clot were determined. The results show that the combination of RVV and H 2 O 2 significantly reduces the clotting time, (p< .001) when compared to each alone.

Abnormal blood clotting is present in many diseases and can be a major cause of death and/or complications. The abnormal clotting of blood may decrease the blood flow and therefore decrease oxygen going to certain organs giving rise to organ failure. A study was performed on pooled, human citrated whole blood (CWB) from which was prepared platelet rich plasma (PRP) and platelet poor plasma (PPP). The clotting times of each CWB, PRP and PPP were determined instrumentally. The CWB has the shortest clotting time, followed by PRP and subsequently followed by PPP (acellular). There were significant differences between the mean values for each of the groups. This data shows that the cellular components of blood contain substances which initiate some aspects of the clotting cascades. The fact that cells alter clotting time indicates that plasma assays alone may not be an effective clinical test to monitor coagulation. It may be that whole blood laboratory tests may be more effective in detecting and monitoring disease than those currently performed on plasma.

Endotoxin (Lipopolysaccharide, LPS) is a part of the outer membrane of the cell wall of gram-negative bacteria. LPS induces activation of the coagulation cascade in humans. This procoagulant effect on citrated whole blood produces a shortened clotting time. Silver ion (Ag/sup +/) denatures the anticoagulant proteins and affects the intrinsic pathway of blood coagulation by producing a shortened clotting time. This in vitro study was performed by mixing human citrated whole blood (CWB) with LPS, silver nitrate (AgNO/sub 3/), and the combination of the two. The clotting time, rate of clot formation, and the maximum strength of the clot were determined. The results show that the combination of LPS and Ag/sup +/ significantly reduces the clotting time (p

The effect of copper ions on the blood coagulation time was determined. In the experiment that was performed in vitro, there were three different aliquots for each blood sample. The three aliquots were composed of the control, 0.05 mM CuSO/sub 4/, and 0.1 mM CuSO/sub 4/. Thirty two microliters of 0.1 M CaCl/sub 2/ was then added to each aliquot to initiate blood coagulation. When the copper ion concentration was increased, there was a significant increase in blood coagulation time.

Tissue factor (TF) is a transmembrane glycoprotein and the main triggering element for blood coagulation. Expression of TF on the cell surfaces and its appearance as a soluble molecule are characteristic features of acute and chronic inflammation in conditions such as arteriosclerosis leading to stroke and myocardial infection. A study was performed on human citrated whole blood, by separating plasma from the red blood cells. Ten microlitres of 25% tissue factor (TF) was added to both the plasma and packed red blood cells (RBC's), and the clotting time, rate of clot formation and the maximum strength of the clot determined. TF bearing samples clotted more rapidly and had greater clot strength when compared to that of control aliquots.

The sedimentation rate (sed rate), also called, the Erythrocyte Sedimentation Rate (ESR) is a blood test for inflammation in the body. If it is elevated, then there is an inflammatory process in the body which can be monitored. The test is broad and non-specific; however, it may determine the effectiveness of therapy for the inflammatory condition. We performed studies on human citrated whole blood by adding 100 microlitres of 1% of MethylCellulose to each of glass and plastic tubes with the blood. The samples (n=12) were incubated at 37/spl deg/ for 10 minutes. Later, the blood from each of the tubes were placed in pipettes, sealed and left undisturbed for an hour. The ESR was measured, and it was found that the sedimentation rate of the blood in plastic settled at a higher rate than the one in glass.

Whether copper sulfate affects the sedimentation rate of erythrocytes in blood was investigated. We performed the experiment by placing by 1ml of blood in plastic vials. After that, we added 10/spl mu/l of 1% CuSO/sub 4/ solution to an aliquot. Then, we put 10/spl mu/l of 5% of CuSO/sub 4/ to 1ml of the same blood into different vial. Following this procedure, we incubated the blood with the various concentrations of CuSO/sub 4/ to 37 degrees Celcius for ten minutes. Then, we determined the sedimentation rates of the red blood cells (RBCs) for the control, the blood that contained .001% of CuSO/sub 4/, and the blood that contained .005% of CuSO/sub 4/. We repeated this experiment with fourteen (n=14) different samples of blood. The results indicate that there was a statistical significance (P

The mercuric ion (Hg/sup 2+/) has been shown to have a procoagulant effect on citrated whole blood through its excitation of the extrinsic pathway. The silver ion (Ag/sup +/) affects the intrinsic pathway of blood coagulation also producing a shortened clotting time. This in vitro study involved mixing citrated whole blood (CWB) with mercuric nitrate Hg(NO/sub 3/)/sub 2/, silver nitrate AgNO/sub 3/, and the combination of the two. The eight samples were incubated for ten minutes at 37/spl deg/C and were analyzed by an Amelung KC 4A clot detector. The results show that the combination of Ag/sup +/ and Hg/sup 2+/ significantly reduces the clotting time (p

The hypochlorite ion (OCl/sup -/) is a powerful oxidant that participates in the pathogenesis of ischemia/reperfusion injury, inflammation, and atherosclerosis. Whether hypochlorite has any anticoagulative properties in blood has previously not been investigated. We performed in vitro studies by spiking human citrated whole blood (CWB) with sodium hypochlorite (NaOCl) at final concentrations of 0 /spl mu/g/mL (control), 9.5 FLg/mL, and 95 /spl mu/g/mL. The samples (n=12) were incubated at 37/spl deg/C for 10 minutes and recalcified with 0.1 M CaCl/sub 2/ to initiate clotting. The clotting or recalcification time (RT) was measured with a Sonoclot Coagulation Analyzer. The results indicate a significant prolongation (p

A rapid blood clotting test for monitoring the thrombin inhibiting activity of the drug hirudin is described. This test, a modified ecarin clotting time may enable the monitoring of a patient's hirudin dosage so that a safe, therapeutic level is achieved. The results show that there was an increase in clotting time with an increased level of hirudin. The data demonstrates a linear correlation between ecalin clotting time prolongation and hirudin content. Each clotting time is significantly prolonged (p