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I Raskó

Publications and source records attributed to I Raskó.

At least 37 records · Page 2Linked to original sources
PubMed1992

Allele frequencies of cystic fibrosis-linked markers and F508 deletion in affected Hungarian families.

Linked marker haplotype analysis of 16 cystic fibrosis (CF)-affected children, 3 fetuses, 1 healthy child and their parents was performed by restriction fragment length polymorphism (RFLP) for J3.11, Met H, Met D, XV-2c, KM.19 markers. Polymerase chain reaction (PCR) to detect the main mutation of CF chromosome, a specific 3 base pair (bp) deletion (delta F508) was also performed in 17 CF patients. Allelic frequencies on analysed CF chromosomes were: J3.11/Taq I 1.0, 0.0, J3.11/Msp I 0.44, 0.56, Met H/Taq I 0.73, 0.27, Met H/Msp I 0.80, 0.20, Met D/Taq I 0.75, 0.25, XV-2c/Taq I 0.85, 0.15, KM.19/Pst I 0.17, 0.83 for allele 1 and 2, respectively. Two markers, Met H and KM.19 were found to be in strong association with the CF mutation. The frequency of the delta F508 mutation on all 34 CF chromosomes was 0.65 (of which 0.73 was homozygous and 0.27 heterozygous for this deletion).

Adult↗
PubMed1992

About DR beta-restriction fragment length polymorphism (RFLP) analysis in kidney transplantation in connection with a paediatric patient.

A retrospective analysis of the HLA-DR antigens was performed at the DR beta DNA locus by the means of restriction fragment length polymorphism (RFLP) in the case of a two-times kidney transplanted paediatric patient and in 16 adult kidney donor recipient pairs in order to prove the importance of DNA molecular analysis in those cases where the serological identification is poor. The child and her grafts (first from her mother, the second from a cadaver donor) carried the DRw6 antigen which serologically can very poorly be defined. According to DR serotyping before transplantation both the child and the cadaver kidney proved to be DR5, 6, while the DNA analysis revealed mismatches; the child possessed the two subtypes: 13b1 and 14a of the DRw6 antigen only and none of the DR5, the cadaver kidney proved to belong to the DR4 antigen group instead of DR5, and furthermore to a different subtype of the DRw6 (13a3) than the recipient. The DNA analysis of other 16 adult donor-recipient pairs also underlined the importance of the DR beta RFLP analysis in cases where the transplantation antigens could be poorly defined.

Adult↗
PubMed1984

Detection of a nerve-specific membrane protein on differentiating PCC3/A/1 cells.

Attempts were made to prepare monoclonal antibodies specifically reactive with cell surface components of a murine neuroblastoma cell line, Neuro 2a. One of the antibodies (1c2) reacts with a varying proportion of in vitro cultivated Neuro 2a cells, but does not react with murine embryonal carcinoma cell lines (PCC3/A/1 and F9) or with a murine fibroblast line (LM). This antibody selectively stains a subpopulation of nerve cells in murine adult central nervous system, e.g. granular cells in cerebellar cortex. Immunoaffinity purification of adult brain and Neuro 2a plasma membrane fractions with the antibody resulted in an electrophoretically pure protein of approx. 28 kD molecular weight as estimated by SDS-PAGE. Although this antigen is absent from PCC3/A/1 embryonal carcinoma cells, it can be demonstrated after 9 days of growth and differentiation under low density conditions by indirect immunoperoxidase staining. This monoclonal antibody may prove useful in further analysis of neural tissue development.

Animals↗
PubMed1984

Spontaneous differentiation in the colonies of a nullipotent embryonal carcinoma cell line (F9).

Experiments were undertaken to reveal the spontaneous differentiation capacity of the nullipotent F9 embryonal-carcinoma (EC) cell line in colonies derived from single cells. Culture conditions which allowed the development of neuroblasts in colonies of the multipotent EC cell line (PCC3) were worked out, and comparative studies on neuroblast differentiation in PCC3 and F9 colonies were conducted. Neural-cell-specific silver impregnation, selective staining of cells having electrically excitable membranes with merocyanine 540 and the observation of nerve processes were considered as differentiation markers. The appearance of neuroblasts in F9 and PCC3 colonies could be detected from the 6th day after seeding. The development of neuroblasts was less prevalent in high-density cultures, especially in the case of F9. By the 8th day in differentiating colonies, PCC3 cells lost much of their colony-forming activity, while F9 cells preserved their original high plating efficiency, in spite of advanced differentiation. The determination of growth parameters during differentiation in colonies led to the conclusion that F9 cells had lost certain growth-control mechanisms which normally restrict the clonal growth of EC cells. It is suggested that the phenomenon of nullipotence may be analysed in terms of the coordinated regulation of proliferation and differentiation of EC cells.

Animals↗
PubMed1979

Pattern of segregation of chicken HPRT phenotype in Chinese hamster-chick red blood cell hybrids.

The pattern of segregation of hypoxanthine phosphoribosyltransferase (HPRT, E.C. 2.4.2.8) was determined in synchronized Chinese hamster-chick red blood cell hybrids. Three hybrid lines were synchronized at the G1-S boundary. Bromodeoxyuridine pulses were subsequently applied throughout the S phase, and the frequency of the segregant clones was determined. It was found that the segregation of the chicken-specific HPRT phenotype associated with the loss of a chromosome was potentiated by bromodeoxyuridine administered during the first hour following release of the block.

Animals↗
PubMed1979

Gene mutation and sister chromatid exchange in Chinese hamster cells.

The mutation in hypoxanthine phosphoribosyl transferase gene and the induction of sister chromatid exchange (SCE) were comparatively studied treating Chinese hamster ovary cells with the mutagens ethylmethanesulphonate. N-methyl-N'-nitro-N-nitrosoguanidine, Mitomycin C and X-ray. All the agents exerted strong mutagenic effects and showed a dose-dependent relationship for the induction of SCEs.

Animals↗
PubMed1978

The effect of bromodeoxyuridine on the segregation of the chicken-specific HPRT gene from Chinese hamster-chick red blood cell somatic hybrids.

The segregation of the chick-specific HPRT gene was studied in three Chinese hamster-chick red blood cell hybrid lines. The three lines showed individual segregation kinetics, the segregation taking place in an exponential-like fashion. Bromodeoxyuridine becomes incorporated into the nuclear DNA and increases the spontaneous segregation rate.

Animals↗
PubMed1970

L-serine deaminating enzymes in Escherichia coli crude extracts.

(a) The measured L-serine deaminating activity of a crude bacterial extract may originate from L-serine deaminase, from biosynthetic L-threonine deaminase, or from degradative L-serine deaminase. Nevertheless, the contribution of the individual enzymes can be determined.(b) About a half of the L-serine deaminating activity of wild type E. coli bacteria, grown in synthetic minimal medium, originates from L-serine deaminase and about half from biosynthetic L-threonine deaminase.(c) Ninety percent of L-serine deaminating activity of wild type E. coli bacteria, grown in yeast extract-tryptone medium, originates from L-serine deaminase, and the remainging ten percent from the degradative L-threonine deaminase.(d) Conditions have been established in which threonine deaminases are eliminated and the activity of L-serine deaminase alone could be measured, even in crude extracts.

Journal Article↗
PubMed1968

L-serine deaminase of Escherichia coli.

The native l-serine deaminase (l-serine hydrolyase, deaminating, EC 4.2.1.13) of Escherichia coli K-12, which seems to be a very labile protein, is rather stable in concentrated solution. Dilution rapidly inactivates it, but in the presence of a saturating concentration of l-serine the molecule is protected from inactivation. It is a very specific enzyme; l-serine is the sole substrate with a K(m) value of 6.60 x 10(-3)m. d-Serine and l-cysteine are competitive inhibitors. Substrate saturation curves of the native enzyme show sigmoid shape, whereas the enzyme liberated from the bacteria in the presence of l-serine exhibits normal Michaelis-Menten kinetics.

Chemical Phenomena↗
PubMedDate not supplied

Apolipoprotein E polymorphism in Pick's disease and in Huntington's disease.

The polymorphism of apolipoprotein E (apoE) has been recognized as a genetic risk factor in different neurodegenerative disorders, with or without tau protein- related neuropathology, but few published epidemiological data are available as concerns the association of different apoE alleles with two relatively rare forms of dementia, Pick's disease (PiD) and Huntington's disease (HD). In this study the frequency of the apoE4 allele was examined in 36 persons with histopathologically proven PiD and compared with that of the apoE genotype in 28 HD probands and 79 aged healthy controls. The E4 allele was overrepresented selectively in PiD (42%) as compared with the control population (7%). No such association was found for HD probands (9%). This finding lends further support to the hypothesis that the E4 genotype is not an Alzheimer's disease specific susceptibility factor, and that it could be present in diverse dementing disorders with tau protein related neuropathology, such as PiD.

Aged↗