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Biomedical subjects

J Coupek

Publications and source records attributed to J Coupek.

14 recordsLinked to original sources
PubMed1979

Correlation of extracts obtained by high efficiency gel chromatography of lactic dehydrogenase virus infected mouse serum and cytosol from human tumors using leukocyte adherence inhibition assay.

Immunochemically active fractions were obtained using Separon Hema-300-glc(R) from serum of lactic dehydrogenase virus (LDV) infected mice and from homogenates of human tumors. The mixture of proteins of tumorous origin from the cytosol giving a positive reaction in the leukocyte adherence inhibition (LAI) test was found in the same fractions showing maximum of absorbance at 340 nm in the spectrophotometer and a corresponding peak in the refractometer. Analogous peaks were not proved in material obtained from healthy controls, but they were found in some human placentas and fetal organs. The LDV fraction obtained from mouse serum served as a "control" antigen in LAI test for human tumor testing, and results corresponded with those obtained using cytosol specific for the tumor under study.

Animals↗
PubMed1977

Reactive carriers of immobilized compounds.

Sphericanl macroporous reactive carriers capable of forming covalent bonds with amino acids and proteins were prepared by the suspension copolymerization of 2-hydroxyethyl methacrylate, ethylene dimethacrylate and p-nitrophenyl esters of methacrylic acid and methacryloyl derivatives of glycine, beta-alanine and epsilon-aminocaproic acid. The effect of the spacer length, pH and the type of the buffer used, concentration of reactive groups in the copolymer, concentration of the ligand and the participation of the hydrolytic and aminolytic reaction of p-nitrophenyl functional groups in the attachment of glycine, D,L-phenylalanine and serumalbumin was studied. Macroporous copolymers containing reactive functional groups can be used as active enzyme carriers, if their activity is not blocked by the presence of p-nitrophenol split off in the attachment reaction.

Carboxylic Acids↗
PubMed1977

Separation of naphthoquinones and lipophilic vitamins by gel and thin-layer chromatography.

A separation of naphthoquinones on silica gel and on silica gel impregnated with polyethylene glycol 200 by thin-layer chromatography was compared with gel permeation chromatography (GPC) on styrene-divinylbenzene copolymer S-832-gel using tetrahydrofuran as mobile phase. Factors affecting the separations attainable are discussed, and it is concluded that GPC is a suitable method for the determination of K vitamins in natural materials.

Chromatography, Gel↗
PubMed1976

Affinity chromatography on hydroxyalkyl methacrylate gels. III. Adsorption of chymotrypsin to poly(hydroxyalkyl methacrylates) with covalently bound benzyloxycarbonyl-glycyl-D-phenylalanine and -D-leucine as function of pH and ionic strength.

Chymotrypsin is specifically adsorbed at low ionic strength and alkaline pH to hydroxyalkyl methacrylate gels with N-benzyloxycarbonylglycl-D-phenylalanine or N-benzyloxycarbonylglycyl-D-leucine attached through 1,6-hexanediamine. Chymotrypsin is not adsorbed either to the unmodified gel (Spheron) or to the gel with attached, 1,6-hexanediamine (NH2-Spheron). The adsorption of chymotrypsin to Z-Gly-D-Phe-NH2-Spheron was investigated as a function of pH and ionic strength. Trypsin is not adsorbed to this gel. Chymotrypsin isolated from a crude pancreatic extract by affinity chromatography on Z-Gly-D-Phe-NH2-Spheron had the same activity as the enzyme isolated on a column of Spheron, to which the naturally-occurring trypsin inhibitor had been coupled.

Binding Sites↗
PubMed1976

Gel chromatography of serum from mice infected with a virus elevating L-lactate: NAD oxidoreductase activity--an attempt to separate viral and enzymatic activities.

Gel chromatography on Spheron P-500 of mouse serum yielded fractions elevating lactate dehydrogenase activity. The order of elution was viral activity, proteins and lactate dehydrogenase activity. Viral contamination occurred also in certain fractions subjected to repeated gel chromatography in which no proteins were detectable.

Animals↗
PubMed1975

Pepsin immobilized by covalent fixation to hydroxyalkyl methacrylate gels: preparation and characterization.

Insoluble active derivatives of pepsin (EC 3.4.23.1) were prepared by covalent binding of this enzyme to hydroxyalkyl methacrylate gels modified with 1,6-diaminohexane or epsilon-aminocaproic acid in an acid medium by means of water-soluble carbodiimide. The amount of attached enzyme, its proteolytic activity, pH activity curves of the preparations obtained and the time and pH dependence of their stability were determined.

Drug Stability↗
PubMed1975

Affinity chromatography on hydroxyalkyl methacrylate gels. II. Isolation of thiol-containing protein and peptide using mercurial derivatives of gels.

Absorption properties of hydroxyalkyl methacrylate gels containing various amounts of mercuri derivatives of p-acetaminophenoxyethyl methacrylates (Hg-APEMA) and methacrylanilide (Hg-MAA) were investigated by means of a reduced Ellman's agent (5,5'-dithiobis-2-nitrobenzoic acid) and papain. The optimum gel was used for the affinity chromatography of SH-protease from beans and for the isolation of a peptide with a free sulphhydryl group from the chymotryptic hydrolyzate of serum albumin.

Buffers↗