Intermediates, purity

Intermediate purity. 50 to 55 percent alumina. The anorthite (needle-structure) form is more resistant to the action of steam exposure. 

Intermediate purity (1-10 factor VI11 units/mg protein)... 

The envelope in Fig. 7.5 is for the maximum increase in terminal velocity obtainable by eliminating surface-active contaminants. For systems of intermediate purity, r may be assigned a value between zero and that given by the envelope. Since the envelope has been derived solely from experiments for aqueous systems, it should be used with caution for nonaqueous systems. 

II Prothrombin deficiency 30-40% 3 days Prothrombin complex concentrates (intermediate purity factor IX concentrates)... 

Von Willebrand Von Willebrand disease 30% Approximately 10 hours Intermediate purity factor VIII concentrates that contain von Willebrand factor. Some patients respond to DDAVP Cryoprecipitate1... 

Peerlinck K, Arnout J, Gilles JG, Saint-Remy JM, Vermylen J. A higher than expected incidence of factor VIII inhibitors in multitransfused haemophilia A patients treated with an intermediate purity pasteurized factor VIII concentrate. Thromb Haemost 1993 69 115-18. 

FIG. 13-53 Liquid-phase mole fraction profiles for ethanol-benzene-water distillation, (a) Low-purity profile, b) Intermediate-purity profile, (c) High-purity profile. 

Factor VIII is available as ultrapure recombinant product, ultrapure plasma-derived product, high purity plasma-derived product and intermediate purity plasma-derived product. 

Recombinant and high-purity coagulation factor products appear to have a greater tendency to induce inhibitors than human-derived concentrates of intermediate or low purity (7). These intermediate-purity or low-purity human-derived concentrates are probably more suitable for inducing immune tolerance in patients with hemophilia with inhibitors. It has been suggested that for immune tolerance a high content of Von Willebrand factor in factor VIII concentrates is required, although direct comparisons of different products have not been made (8). 

Thromboembolic complications developed in two of 81 patients with Von Willebrand disease treated with a high-purity factor VlllWon Willebrand factor (VWF) concentrate (10). Four cases of venous thrombosis were reported in patients with Von Willebrand disease treated with an intermediate-purity factor VIII/VWF concentrate. Use of pure VWF concentrate without increased factor VlllrC is preferable (11). 

Patients with hemophilia have various disturbances of immune function, resulting not only from infections with HIV and hepatitis, but also from chronic exposure to extraneous proteins in clotting factor concentrates (51). Protein contaminants, such as immunoglobulins, fibrinogen, and fibronectin, can depress immune function. It has been postulated that high-purity concentrates in HIV-positive hemophiliacs are associated with better maintenance of CD4+ cells and other indicators of immune function compared with products of intermediate purity (51). 

Makris M, Colvin B, Gupta V, Shields ML, Smith MP. Venous thrombosis following the use of intermediate purity... 

Rochat C, McFadyen ML, Schwyzer R, Gillham A, Cruickshank A. Continuous infusion of intermediate-purity factor VIII in haemophilia A patients undergoing elective surgery. Haemophilia 1999 5(3) 181-6. 

Prowse CV, Griffin B, Pepper DS, et al. Changes in factor VIII complex activities during the production of a clinical intermediate purity factor VIII concentrate. Thromb Haemost 1981 46 597-... 

All fermentation or bioprocesses start with the selection of the cell type. The choice is dependent on the product synthesized, the amount of product needed, the purity of the required product, and of course the cost. A bio-pharmaceutical such as an antibiotic, antibody, or protein that is directly injected into a human requires a highly pure product, whereas food products require intermediate purity, while commodity products such as ethanol produced for alternative fuel usage do not require as stringent sterile methodology. The advantages and disadvantages of the major classes or cell types are summarized in Table 1. 

Factor VIII concentrates can be classified according to their level of purity, which refers to the specific activity of factor VIII in the product. Cryoprecipitate is a low-purity product, containing a specific factor VIII activity level of less than 5 units/mg of protein. This product is no longer considered a primary treatment for factor VIE deficiency in countries where factor VEI concentrates are available, because cryoprecipitate does not undergo a viral inactivation process. Intermediate-purity products have a specific activity of factor VIE of 1 to 10 units/mg of protein, while high-purity products have a specific activity of 50 to 1,000 units/mg of protein. Ultrahigh-purity plasma-derived products are prepared with monoclonal antibody purification steps and have a specific activity of 3,000 units/mg of protein prior to the addition of albumin as a stabihzer. 

Because of the greater carbon and nitrogen contents of the intermediate-purity ferritic stainless steels, prevention of susceptibility to intergranular corrosion is more difficult than with the ultrahigh-purity alloys. Small amounts of niobium and/or titanium are added to combine... 

Isotherms disclose the potential utility of countercurrent use of carbon in a given application. It will be recalled that in counter-current application, the once-used carbon after being filtered from the completely purified liquid, is re-used to bring another batch of untreated liquid to an intermediate purity. The capacity to do this... 

Table 3 contains the chemical analyses of the brick samples tested in the simulative checker test. A high-purity magnesia brick, two intermediate-purity magnesia brick, and a magnesia-zircon brick were tested. 

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