Biomedical subjects
Publications and source records attributed to A Trochimczuk.
The literature review dealing with participation of proteolytic enzymes in initiation and execution of apoptosis was done. Cysteine proteases with Asp-X cleavage specificity, called caspases, play the main role in this process. The other proteases such calpains and proteasomes take also part in apoptosis. The proteases degrade proteins of cytoskeleton and structural proteins of nucleus, they also activate proendonucleases.
Copolymers of butyl acrylate and ethylene glycol dimethacrylate with various degree of crosslinking and aminolysis were used for penicillin acylase immobilization. The amount and activity of the bound protein decreased with the decrease of crosslinking when copolymers having nearly constant degrees of aminolysis were compared. The increase of the carrier amino group content increased the ability to bind the protein (by glutaraldehyde method) without a proportional rise of enzyme activity. The comparative studies of immobilization effect and performance of the derivatives showed 40% crosslinked EGDMA, having an amino group content of 0.67 mmol g-3, to be the carrier of choice. This selected carrier was tested for active protein immobilization by use of crude acylase preparation. It was shown that up to a protein concentration of 9 mg cm-3 in the immobilization mixture the active protein was preferentially bound to the polymer matrix. It was indicated also that the derivative stability was mostly affected by multipoint attachment of the enzyme to the carrier surface.
Applications of various sorbents and ion-exchange resins to hemoperfusion are reviewed. With respect to the type of processes accompanying removal of toxines from blood, the fillings of hemoperfusion columns are classified into the group of: sorbents, iono-sorbents and ion-exchangers, immunoadsorbents. Possibilities of improving hemocompatibility of polymeric materials used in hemoperfusion columns by a sorptive or covalent covering their surfaces with natural materials-heparin and/or albumin are discussed.
In this work the way of chemical modification of macroporous polymer sorbents with a styrene-divinyl-benzene++ structure was presented. Their modification with amino acids leads to improvement of hemocompatibility of sorbents and to sorption magnification, particularly of hydrophilic polysorbates. In the work the full physical chemical characteristics of the received products was given and their sorption properties in the relation to urea, vitamin B12 and substances from phosphor-organic pesticides group as well as from barbituric acid derivatives were designated.
The changes occurring in human blood after contact with hydrophobic sorbent Vinylsorb S and with ionosorbents Vinylsorb SS were studied. The investigations were carried out using static method at room temperature. The time of contact was 2 h. It was found that the effect of all sorbents upon the morphological elements of blood was small, only platelets were sorbed to a significant extent. The effect of sorbents upon the clotting proteins was also small and plasma hemostasis should not be affected. The sorbents containing sulphonic groups significantly activate kallikreinogenesis and may intensify shock symptoms.
Among several various acrylic copolymer used as carriers for anti-bovine serum albumin the best are copolymers obtained from acrylonitrile and ethyl or butyl acrylate crosslinked with divinylbenzene which after aminolysis with di- or triamines were activated with glutardialdehyde. The immunoadsorbents thus obtained were successfully used for purification of bovine serum albumin from bovine serum or from crude fraction of the albumin by immunoaffinity chromatography. Electrophoretically pure bovine albumin was eluted from immunoadsorbent column with deionised water and with glycine/HCl buffer, pH 2.5. The albumin was contamined with less than 0.1% of bovine immunoglobulins and with 0.05% of rabbit immunoglobulins. No contamination with rabbit immunoglobulin was observed when immunoadsorbents were pre-treated with sodium borohydride.