Clot strength

Figure 2. Clotting of micellar casein by rennet at different ionic strengths. Absorbance measurements in the Cary 14 spectrophotometer at 500 nm in 0.5-cf cuvettes 35°C skim milk diluted 16 times clotting strength in reaction mixture 1.43 SU. Time flows to the left. (A) I = 0.04 (B) I = 0.06 (C) I = 0.12.

Figure 4. Showing the influence of the ionic strength on the enzymatic clotting time of K-casein (0.1 g/100 mL) at pH 6.7 and 35°C. Clotting strength in reaction mixture, 0.8 SU.

Figure 6. Arrhenius plot for the clotting of K-casein brought about by rennet. Experimental conditions pH 6.7 I = 0.2 31.5°C. Kappa-casein concentration 0.1 g/100 mL clotting strength in reaction mixture, 3.97...

I 8 Gurbel PA, Zaman K, Bliden KR Tantry US. Maximum clot strength is a novel and highly predictive indicator of restenosis a... 

Clot strength (G in dynes per square centimeter) defined by G = (5000MA)/(96-MA). In a tissue factor-modified TEG (Khurana et al. 1997), clot strength is clearly a function of platelet concentration. 

To study the clotting of micellar casein skim milk prepared from low-heat skim milk powder was diluted 16 times with 0.01 M CaCl2, to which NaCl was added to adjust the ionic strength. 

Some characteristic clotting curves of micellar casein at 35° C and different ionic strength are shown in Figure 2. It is seen that an increase of the ionic strength brings about an extension of the lag phase with a simultaneous disappearance of the minimum. This indicates, as explained in the introduction, that salt chiefly decreases the rate of proteolysis. 

The influence of the ionic strength on the clotting time of -casein at 35°C is shown in Figure 4. The pronounced minimum is strongly reminiscent of the minimum found with milk (11,12), though it occurs at a considerably lower ionic strength. 

The Influence of the Ionic Strength on the Clotting Time. We have seen that between I = 0.03 and 0.5 an increase of the ionic strength chiefly brings about a decrease of the rate of proteolysis. We shall now present a simple argument to explain the effect of salt and to show the importance of the cluster of cationic residues around the labile Phe-Met bond in -casein (5) in stabilizing the ES-complex. If the latter is identified with Bronsted s activated complex (13), one has for the rate of proteolysis... 

In the cardiovascular system, there is a 10 to 20 beat per minute increase in heart rate, a 5-10 mm increase in blood pressure, and an increase in the strength of heart contractions. Nicotine increases the incidence of cardiac arrhythmia (irregular heartbeat) in susceptible people. It causes constriction of blood vessels in the skin, and causes platelets to adhere together leading to an increased possibility of blood clots. 

Less than 1% of the applied coagulant activity is recovered in fraction Nos. 1, 2, 3, 4. Fraction 1 however possesses proteolytic activtity which in concentrated solutions would dissolve fibrin clots. The thrombin-like activity is eluted from these columns in significant amounts at a buffer strength of 0.04 M or greater. 

The third problem in the blood-coagulation scenario is that it avoids the crucial issues of how much, how fast, when, and where. Nothing is said about the amount of clotting material initially available, the strength of the clot that would be formed by a primitive system, the length of time the clot would take to form once a cut ocurred, what fluid pressure the clot would resist, how detrimental the... 

Maximum amplitude (MA) greatest amplitude on the TEG trace. MA represents the absolute strength of the fibrin clot and is a direct function of the maximum dynamic strength of fibrin and platelets. 

Negatively charged acylneuraminic acid residues impart a certain strength to cell membranes because of their mutual repulsion, and influence the mutual adhesion of cells in the organ structure. Whereas neuraminic acid allows the aggregation of embryonal muscle cells of the hen, presumably via Ca bridges, it prevents spontaneous clumping of blood platelets, and it so opposes any undesirable formation of blood clots. 

The following two papers compare M-C and H-C bond strengths on the basis of high-level MO calculations E. Clot, C. Megret, O. Eisenstein, and R. N. Perutz, J. Am. Chem. Soc.,... 

Stony, J.E., and Ford, G.D. (1982). Some factors affecting the post clotting development of coagulum strength in renneted milk. J. Dairy Res. 49,469-477. 

---