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Z Katona

Publications and source records attributed to Z Katona.

10 recordsLinked to original sources
PubMed1992

The cerebroside sulfate activator from pig kidney: purification and molecular structure.

The activator protein for hydrolysis of cerebroside sulfate by arylsulfatase A was purified from pig kidney in high yield. This protein, also known as sphingolipid activator protein-1 and saposin-B, was particularly rich in pig kidney. Purification was achieved by a simple procedure involving homogenation and heat treatment followed by affinity, ion exchange, and gel filtration chromatographies. The final product was better than 90% pure by gel electrophoresis and HPLC. It was possible to sequence more than 60 amino acids from the N-terminus with only a few uncertain residues. The sequence differed from that predicted for the human protein by about 10%, with most amino acid variations being conservative. There appeared to be a residual glycosyl substituent on asparagine 21, but the sugar content was low and the protein failed to bind to concanavalin A. The cerebroside sulfate activator proved to be exceptionally resistant to denaturation or protease digestion. The apparent molecular mass was approximately 20,000 Da on preparative gel-filtration columns, but was variable when estimated by HPLC gel filtration. Values ranging from 30,000 to over 100,000 Da were observed in neutral buffers, while values around 15,000-16,000 Da were seen in acidic buffers such as those used for assay of the biological activity. This was further decreased to a putative subunit of 7000-8000 Da under severe denaturing conditions. Pig kidney is a convenient source for the large-scale preparation of this interesting protein which has heretofore been obtained from human sources.

Amino Acid Sequence↗
PubMed1992

The cerebroside sulfate activator from pig kidney: derivitization, cerebroside sulfate binding, and metabolic correction.

Highly purified cerebroside sulfate activator from pig kidneys was characterized by a number of chemical and biological procedures. Methods for chemical modifications were evaluated in an attempt to obtain biologically active derivatives. Iodination, dabsylation, and to a lesser degree reductive methylation provided useful products with good retention of cerebroside sulfate activator activity. Other procedures resulted in largely inactive derivatives or losses in both protein and biological activities. Attempts at renaturation of cerebroside sulfate activator subjected to various denaturing conditions appeared to be successful in many instances, but it was uncertain if the protein structure had actually been disrupted. The binding of cerebroside sulfate by activator was estimated by gel filtration under conditions similar to those of its assay. The formation of a relatively stable 1:1 complex was observed, collaborating results with the human protein. The complex was stable enough to be isolated and shown to be an efficient substrate for arylsulfatase A. The effectiveness of the pig kidney cerebroside sulfate activator for correcting the metabolic defect in activator-deficient human fibroblasts was compared with human materials. The pig kidney protein was taken up more efficiently by the cells and resulted in a better metabolic correction than material from human liver, but was somewhat less effective than a preparation from human urine.

Animals↗
PubMed1979

Position of bioengineering education in Hungary.

Medical electronic equipment has been produced in Hungary since the early forties. Industrial production of bioengineering started only in 1957. At the same time the bioengineering section of the Scientific Society of Measurement and Automation was founded. This Section was instrumental in recognizing the necessity for and establishing a structured education programme in bioengineering which started in the Postgraduate Institute for Engineers within Budapest Technical University. Later this was incorporated in the programme of the Technical University as an optional subject. Today there is also a specialised engineering course at the Technical University. There are significant developments in the bioengineering education of physicians and medical students. This paper deals with the possibility of classification bioengineering devices which has proved useful in education in Hungary.

Biomedical Engineering↗
PubMed1975

Automatic indirect sphygmomanometry.

After discussing the different methods of indirect blood pressure measurement the paper describes the fully automatic indirect blood pressure measuring apparatus, Type AVM-2 and AVM-4, development in Hungary. Experience gained using these instruments is reported and the requirements for this type of instrument outlined. Finally the paper discusses the most important characteristics of this equipment.

Automation↗