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T Brodniewicz-Proba

Publications and source records attributed to T Brodniewicz-Proba.

10 recordsLinked to original sources
PubMed1991

Human plasma fractionation and the impact of new technologies on the use and quality of plasma-derived products.

Recent years brought several important changes in the domain of human plasma derived products. High purity and effective anti-viral treatment became a reality. This radically improved the quality of patient treatment. At the same time recent discoveries in molecular biology paved the way for the production of several crucial plasma components by recombinant technology. In the light of these developments the future possibilities for different plasma components production is widely discussed and the eventual benefit of more expensive technologies is being evaluated. This paper, analyzes and presents methods applied by different producers to obtain plasma derived components preparations. The impact of these technologies, the quality of the products and the future of the plasma industry is being discussed.

Biotechnology↗
PubMed1991

Large-scale preparation of a highly purified solvent-detergent treated factor VIII concentrate.

Large-scale adaptation of a recently reported glycine precipitation method for the production of factor VIII (FVIII) concentrate is described. Scaling up of the method required some modification including the addition of aluminum hydroxide to the glycine buffer to reduce the level of contaminating proteins in the final preparation and the use of centrifugation to replace filtration by glass beads. Furthermore, the resultant product was virus inactivated by incorporation of the organic solvent and detergent technique. At industrial level, the modified method gave a good recovery of FVIII activity (230 IU/l plasma) with high purity (4 IU/mg protein). The final product, after virus inactivation and lyophilization, yielded 185 IU of FVIII activity per liter of starting plasma and was considered to be suitable for clinical evaluation.

Detergents↗
PubMed1989

The interaction between human blood-coagulation factor VIII and von Willebrand factor. Characterization of a high-affinity binding site on factor VIII.

The interaction between human Factor VIII and immobilized multimeric von Willebrand Factor (vWF) was characterized. Equilibrium binding studies indicated the presence of multiple classes of Factor VIII-binding sites on vWF. The high-affinity binding (Kd = 2.1 x 10(-10) M) was restricted to only 1-2% of the vWF subunits. Competition studies with monoclonal antibodies with known epitopes demonstrated that the Factor VIII sequence Lys1673-Arg1689 is involved in the high-affinity interaction with vWF.

Amino Acid Sequence↗
PubMed1987

Modified glycine precipitation technique for the preparation of factor VIII concentrate of high purity and high stability.

A modification of the glycine precipitation method for the production of factor VIII concentrate is reported. In this procedure, cryoprecipitate was prepared, washed and dissolved in buffer. Contaminating fibrinogen was precipitated by the addition of 2.8 M glycine buffer at 30 degrees C. The fibrinogen precipitate was removed by filtration using a layer of glass beads. Factor VIII was then precipitated from the filtrate by adding solid NaCl. After centrifugation, the precipitate was resuspended in buffer, desalted, sterilized by filtration, lyophilized and subjected to dry-heat treatment. The procedure gave a good recovery of factor VIII (280 IU/l) and seems applicable to large-scale production. The resulting factor VIII concentrate was especially characterized by its high purity (10 IU/mg) and stability both in the liquid state and during dry-heat treatment.

Chemical Precipitation↗
PubMed1980

Properties of a terminal deoxyribonucleotidyltransferase isolated from wheat germ.

An enzyme able to catalyse the polymerization of deoxyribonucleotides in a template-independent manner was isolated from dry wheat germ. This activity is associated with a soluble protein which is homogeneous with respect to the molecular weight (approx. 500000) and, under denaturing conditions, dissociates into product of two size classes, 67000 and 45000 daltons respectively. The enzyme-catalysed polymerization can be primed by oligo- as well as poly-deoxyribonucleotides, and is highly efficient (234 nmol/h per mg of finally purified protein) when only one of the four deoxyribonucleoside 5'-triphosphates is present in the incubation mixture. An extension of the 3'-hydroxy termini of polydeoxyribonucleotide chains for approx. 40 nucleotide residues was achieved when non-denatured DNA and [3H]dTTP were used as the primer and substrate respectively. It is concluded that the enzyme isolated from wheat germ shares catalytic properties with the terminal deoxynucleotidyltransferase of mammalian thymus. Unlike that transferase, however, the plant enzyme prefers non-denatured to single-stranded DNA as primer and requires both Mg2+ and Mn2+ ions for maximal activity.

Catalysis↗
PubMed1976

RNA polymerases I and II in germinating wheat embryo.

1. The RNA polymerase I was practically absent in the resting embryos and appeared several hours after the beginning of imbibition, whereas the level of polymerase II was high in the resting embryos and did not increase significantly during the imbibition phase. 2. Incorporation in vivo of [14C]valine into polymerase I and II indicated that the synthesis of RNA polymerase I is initiated in germinating embryos much earlier than that of RNA polymerase II. 3. It is suggested that RNA polymerase II is stored in resting wheat embryos to support mRNA synthesis at the onset of germination, whereas the RNA polymerase I activity appears at a further stage of germination.

Amanitins↗
PubMedDate not supplied

Ultrastructural localization of factor VIII procoagulant antigen in human liver hepatocytes.

Factor VIII is generally believed to circulate in blood as a multimeric complex of two glycoproteins which are physiologically and immunologically distinct. One component of the factor VIII complex is factor VIII procoagulant activity (FVIII:C) which is associated with factor VIII/procoagulant antigen (FVIII:Ag, formerly FVIII/CAg). The second, larger unit of the complex is factor VIII/von Willebrand factor (vWF:Ag, formerly factor VIII-related antigen or FVIIIRAg). FVIII:C has anti-haemophilic activity and is defective or deficient in patients with classical haemophilia, and vWF:Ag is absent in patients with von Willebrand disease. FVIII:Ag was demonstrated recently in endothelial cells lining hepatic sinusoids, by using immunoperoxidase staining and light microscopy, whereas biochemical data had indicated its presence predominantly in the hepatocyte fractions and in lesser amounts in endothelial cells. Moreover, recent hybridization experiments detected FVIII:C messenger RNA in liver and kidney tissues. Despite several efforts, the cells responsible for FVIII:C synthesis have not been unequivocally identified. Here we use protein A-gold complex labelling to demonstrate the ultrastructural localization of FVIII:C in human liver cells; the results indicate that hepatocytes may synthesize FVIII:Ag.

Antibodies, Monoclonal↗