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Biomedical subjects

I László

Publications and source records attributed to I László.

At least 19 recordsLinked to original sources
PubMed1998

Plant tissue culture as a model for study of diversity in formaldehyde binding.

The effect of endogenous formaldehyde (HCHO) deprivation with dimedone - as abiotic stress - was investigated on the methylation-demethylation reactions in Datura innoxia Mill. callus cultures. The matrix assisted laser desorption/ionization mass spectrometric (MALDI MS) investigation of the culture extracts revealed characteristic differences between the tissues cultivated in light and dark. MALDI MS data show the presence of a precursor molecule and its mono- and tri-hydroxymethyl derivative, only in the cultures maintained in light. The relative amount of the different derivatives changed considerably, as a consequence of dimedone application in the culture medium and during the extraction.

Culture Techniques↗
PubMed1998

Formaldehyde generators and capturers as influencing factors of mitotic and apoptotic processes.

There is a growing amount of evidence pointing to the fact that several endogenous and exogenous methylated compounds are potential formaldehyde generators in their biological reactions. N(G)-methylated lysines, N(G)-methylated as well as hydroxymethylated arginines, and 1'-methyl-ascorbigen have been examined in this respect. The apoptosis-inducing effect of formaldehyde molecules formed from methyl groups was earlier first published by our group. Dimedone, an artificial capturer molecule for formaldehyde, has been found to prevent the apoptosis-inducing effect of 1'-methyl-ascorbigen as well as N(G)-hydroxymethylated arginines. More recently resveratrol, present in grapes and wines, has been shown to have cardioprotective and cancer chemopreventive effect. Our group has been successful in demonstrating that this natural formaldehyde capturer molecule can also influence cell proliferation and apoptosis. The apoptosis-inducing or -preventing effect of formaldehyde generators and capturers seems to be dose-dependent and may be utilized in various disturbances of cell proliferation and active cell death.

Apoptosis↗
PubMed1981

Localization of thiamine pyrophosphatase activity in motor end plates.

Thiamine pyrophosphatase (TPPase) activity was localized in the terminal arborization of the motor end plates both in rat and frog striated muscles. Electron microscopically the end product of the enzyme was seen in synaptic vesicles. That TPPase was axonally transported was indicated by its localization following experimental ligation of peripheral nerves. It is thus possible that TPPase may play a role in the synthesis of the synaptic mediator substance of the neuromuscular junction.

Animals↗
PubMed1980

Local production of proteins in normal human bronchial secretion.

Concentrations of albumin, IgG, IgA, IgM, alpha 1-acid glycoprotein, alpha 1-antitrypsin, alpha 2-macroglobulin, transferrin, haptoglobin, and coeruloplasmin were determined by radial immunodiffusion in the blood sera and bronchial washings of 8 patients without clinical, radiologic or bronchoscopic evidence of lung diseases. The local production of the proteins was calculated with a formula used by Deuschl and Johansson for the estimation of local synthesis of bronchial immunoglobulins. The formula was completed by a reduction factor established by the authors, based on their previous investigations. The calculations indicated that the individual proteins were secreted locally in various percentages of the total amount found in the secretion, as follows: IgG, 37%; IgA, 84.5%; transferrin, 44.5%, alpha 1-antitrypsin, 15.2%; coeruloplasmin, 11.3%. Local synthesis of IgM was found only in 3 patients. The alpha 1-acid glycoprotein and the haptoglobin do not seem to be secreted locally by the normal bronchial mucosa; they reach the mucus from blood only, through ultrafiltration.

Albumins↗
PubMed1975

Electron histochemistry of thiamine pyrophosphatase activity in the neuronal golgi apparatus observed after axotomy and transneuronal deprivation.

Thiamine pyrophosphatase activity of the neuronal Golgi apparatus exhibits specific patterns, characterizing nerve cell types of the rat spinal cord at the light microscopal level. Electron histochemistry reveals TPPase activity within cisterns of the internal part of the dictiosomes and in vesicles associated with the Golgi system. According to electron microscopical studies performed on semi-thin (0.5 mu) sections, TTPase activity outlines a three-dimensional system of fenestrated cisterns and cisterns and vesicles. In accord with literature data, asotomy of motoneurones results in a light microscopic decrease of dictiosomal TTPase activity and in an electron microscopic hypertrophy of the Golgi system. Electron histochemically, TTPase in the hepertrophied cisterns exhibits a sporadic, patchy localization, which is completely restored only in the state of restitution. On the contrary, transection of dorsal roots does not induce any light- or electron microscopic alterations in the TPPase activity of cells in the substantia gelatinosa Rolandi. Alterations of neuronal TPPase reaction offer a methodological possibility for hodological studies.

Animals↗