Fibrinogen drying

This is a dry sponge of human fibrin prepared by elotting a foam of human fibrinogen solution with human thrombin. It is then freeze-dried, cut into shapes and sterilized by dry heat at 130°C for 3 hours. Before use, it is saturated with thrombin solution. Blood coagulation occurs in contact with the thrombin in the interstices of the foam. 

Cohn, and their associates in Harvard during World War II in their efforts to isolate serum proteins for clinical use. Traces of the organic solvents were removed during the freeze-drying of the different preparations. In the U.K. plasma fibrinogen was obtained by Kekwick and his colleagues by low-temperature precipitation with ether. Serum proteins acquired by these chemical methods were mixtures. 

Fig. 43 Dry thickness of poly(2-hydroxyethyl methacrylate) (PHEMA) as a function of the position on the substrate (lower panel). The fluorescence microscopy images show the corresponding structure of fibrinogen at three positions along the PHEMA gradient (upper panel). (Reproduced with permission from [164])...

Fertilization inhibition. Hot water extract of the roasted seed, administered in the drinking water of female rats at variable doses daily for 30 weeks, was inactive . Fibrinogen level increase. Hot water extract of the dried seed, administered to adults at a dose of five cups/day, produced weak activity ". 

Dried human thrombin. A preparation of the enzyme that converts human fibrinogen into fibrin. It is obtained front liquid human plasma and may be prepared by predpiiaiiiun with suitable gaits and Organic solvents under controlled conditions of pH, ionic strength, and temperature. 

Table V. Effects of Substrate and of Drying on Conversion of Pre-adsorbed Fibrinogen and on Desorption by Plasma...

After rinse and air drying, slide was covered over one horizontal area with anti-fibrinogen serum (f), over another with anti-7s gamma-globulin serum. Both were rinsed off 2 min later (see text). Note area of g on one is clearly visible, indicating the plasma had not fully converted its own globulin deposit... 

Fibrinolytic effects of garlic have also been evaluated. Garlic oil was shown to increase fibrinolytic activity by 55% (p <0.01) after 3 months of treatment, with 2 g twice daily for 3 months. Fibrinogen was not affected (24). A dried garlic preparation (Sapec) was shown to significantly increase tissue plasminogen activator activity compared to placebo after 1 day and 14 days of treatment (23). 

Many PD patients secrete large quantities of fibrinogen into the peritoneal cavity, which results in fibrin formation. This can lead to intraperitoneal adhesions and outflow obstruction. Intraperitoneal heparin may prevent this complication as a result of its local an-tiflbrin effect. Because standard heparin has a molecular weight of 12,000 to 15,000 daltons, it is minimally absorbed and thereby has limited systemic effects. The absorption of intraperitoneal erythropoietin has also been studied. Its bioavailability is low, but may be increased when added into a dry peritoneum. ... 

Figure 5 depicts similar results for Cohn I fibrinogen. Air drying was shown to have a marked disruptive effect on the adsorbate (Figure 5a). The morphology of the adsorbate differed from that of the air-dried y-globulin however, the morphology and pore size of the critical-point-dried adsorbate (Figure 5b) were similar to those for y-globulin. Comparison of the...

Figure 5. Cohn I fibrinogen, 3 mg/dL, adsorbed on Teflon (partial gold decoration technique). Key a, air dried, sintered Teflon b, critical-point dried, sintered Teflon and c, critical-point dried, Fluorofilm Teflon. Bar equals 0.1 p,mfor b and c.

Figure 9. Albumin, 2500 mg/dL solution, preadsorped on sintered Teflon followed by Cohn I fibrinogen, 300 mg/dL, lh each (critical-point dry and PGDTEM techniques). Key bar equals 0.1 pm.

Figure 10. Summary of albumin preadsorption results on a number of polymers. Air drying and PGDTEM were used for all samples. Key F, 30 mg % fibrinogen (Cohn I) and A Fy 2500 mg % albumin followed by 30 mg % fibrinogen (Cohn I).

Air-exposed albumin aggregates more extensively than the critical-point-dried albumin adsorbate. Yet in both cases, no evidence of the ability (similar to that of fibrinogen, fibronectin, and 7-globulin) to support extensive films in tension during the dehydration process exists. 

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