Blood, defibrinated

Benzyl alcohol, 23, 14 BeNZYLAMINE, a-METHYL-, 23, 68 Benzyl carbamate, 23, 14 Benzyl chloride, 21, 99 Benzyl chloroeormate, 23, 13 Benzyl cyanide, 23, 71 Bisulfite compound, use for purification of an aldehyde, 23, 78 use for purification of a ketone, 23, 79 Blood, defibrinated, 21, 53 Booster pump, use of, for hydrogenation, 23, 69... 

Application of Impedance. Initial use of impedance centered on the conductive measurement of microbial metabolic products. As microorganisms grow, their metabolic products increase the conductivity of a medium. For example, the conductivity of putrefying defibrinated blood increased over time (30). Clinical microbiologists used impedance to detect urinary tract infections in half the time of standard methods (31). 

In a 5-I. round-bottomed flask equipped with a thermometer, reflux condenser, and dropping funnel are placed 4 1. of glacial acetic acid and 1 g. of sodium chloride. The acid is heated to boiling on a sand bath until the sodium chloride is in solution, and then 1 1. of defibrinated blood (Note 1) is added in a thin stream from the dropping funnel over a period of about thirty minutes. The blood should not touch the sides of the flask. 

The results of Figure 11 are in striking contrast. Here, when the liver perfusion is carried out with completely defibrinated blood, there is a remarkable net synthesis of fibrinogen which becomes prominent only after the second to third hour and is impressive by the fifth and sixth hours. The chemically measured circulating level of fibrinogen has increased some 60 mg. % above that present in the zero time specimens. Net synthesis of fibrinogen of this magnitude has been repeatedly obtained in more than 25 perfusion studies which will be detailed elsewhere. 

The exclusive role of the liver in the biosynthesis of fibrinogen, questioned by some, has been reaffirmed in isolated liver perfusion experiments in which maximal net biosynthesis of fibrinogen of 0.6 mg. per hour per gram wet weight of liver occurs. This approximates three to four times the normal rate of fibrinogen biosynthesis in turnover in the intact normal rat and occurs only in liver perfusions in which the stimulus of extreme hypofibrinogenemia associated with the use of completely defibrinated blood is present. 

Blood.1—The defibrinated blood of a dog was submitted to electrolysis by Becquerel. He made use of platinum electrodes and a current furnished by a battery of three Daniell cells. At the negative pole he observed the following phenomena ... 

Variation in diameter of distal tubules of uterine gland during second pregnancy cycle of G. m. morsltans fed jhi vitro on day 1 with 20-OHE (4 ug/50 mg blood) in defibrinated pig blood compared with control (analysis of variance gives P<.001 for treatment and time on day 5-7). (Vertical bars S.D.) "Reproduced with permission from Ref. 10. Copyright 1981 Insect Sci. Applic. Pergamon Press, Oxford. ... 

Maximum likelihood problt analysis (65) of dose response data for larval mortality obtained following addition of Ivermectin to defibrinated pig blood fed once in vitro to pregnant G. m. morsltans (x2 (7df) 8.82 ns)... 

Chocolate agar is a polypeptone or beef infusion agar enriched with 2% hemoglobin released from defibrinated heated rabbit s or sheep s blood. The blood hemolysis creates the chocolate color. Free hemin and nicotinamide... 

If an anticoagulant has been added to the blood and the plasma isolated, it may be advisable to defibrinate the plasma to yield a serum analog. The method for this varies according to the anticoagulant for citrate, add 1 % of a solution of thrombin (lOOIU/mLin IMCaClg). For heparin, add 1% protamine sulfate solution (5 mg/mL) and thrombin as above. 

Concern over the fate of the bound complex appears unnecessary, since radiolabeled thrombin or thrombin-antithrombin III complexes were readily displaced from the surfaces by defibrinated plasma containing crude antithrombin III. Therefore, the bound heparin apparently does not become saturated with inactive complex, enabling the bound heparin, if it remains active, to act catalytically to potentiate the inactivation of thrombin as it is generated. Whether the consumption rate of antithrombin III or prothrombin, on the other hand, can be controlled, or whether it would result in a systemic blood defect, remains to be examined. 

SP Sephadex as before ( 1 0) using a modification of the method of Lundblad et al. (JJ ) to produce a product with a specific activity of 1850 NIH U/mg (). Purified human a-thrombin (3000 - 31 53 NIH U/mg) was the kind gift of Dr. J.W. Fenton II (N,Y. State Department of Health). Heat defibrinated citrated human plasma (5 °C, 5 min) was used as a source of crude antithrombin III (0.2 mg/mL). Purified human antithrombin III (1000 U/mg 1 mL plasma = 100 U) was the kind gift of Dr. M. Wickerhauser (American Red Cross, Bethesda, MD). A purified human antithrombin III of similiar activity to that of Wickerhauser (0.29 mg/mL) was also prepared from citrated human plasma (Red Cross Blood Bank, Toronto) using heparin-Sepharose (13). 

To obtain thrombin, it is possible to use either a maceration of leucocytes, or extracts of muscles or of lymphatic ganglia. Schmidt flrst isolated the enzyme from defibrinated blood by precipitation with alcohol. To one part of serum he adds twenty parts of alcohol. A precipitate of albuminoid substances forms, which carries with it the thrombin. The contact with alcohol is prolonged for two or three months, which renders the coagulum almost entirely insoluble in water. Then the precipitate is filtered and is dried in vacuo over H2SO4. On treating with warm water, the enzyme dissolves and not the albuminoids. The solution so obtained shows great activity, and if a little is added to plasma, there results a coagulation infinitely more rapid than that which results under ordinary conditions. 

The thrombin may also be extracted from fibrin which is precipitated during the coagulation. The blood, freshly collected, is first of all diluted to prevent a sudden coagulation. It is left undisturbed for some time, and then is whipped with a small brush to produce defibrination. The fresh fibrin is then treated with a 0.5% solution of NaCl, a concentration sufifident to dissolve the enzyme, but too dilute to attack the fibrin. Thus is obtained a very active solution of thrombin. 

After straining, heparinization, or defibrination, hemin is separated from blood by pouring the blood into hot acetic acid containing sodium chloride. On cooling, the hemin separates. Another method is to precipitate the globin protein with strontium chloride and concentrate the filtrate, from which hemin crystallises. 

---