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J Wimmerová

Publications and source records attributed to J Wimmerová.

17 recordsLinked to original sources

[Soluble elastin and antibody formation].

In the present study, we have obtained antibodies in rabbits to peptides prepared by digestion of elastin with either oxalic acid or phosphoric acid. By Elisa assay, we have shown the lowest production of antibodies against elastin-derived peptides prepared by digestion of N-elastin with phosphoric acid. We have found a strong cross-reactivity between antibodies obtained to peptides prepared by different digestion of insoluble elastin from bovine ligamentum nuchae or aorta and these antigens. A less pronounced cross-reactivity was observed in case of elastin-derived peptides from porcine aorta.

Animals↗

No embryotoxicity of exogenous alpha-elastin evidenced through interference with the chick embryonic morphogenetic systems.

The effects of alpha-elastin (1) on the morphogenetic systems of the chick embryo were studied by means of the CHEST (chick embryotoxicity screening test). The subgerminal administration of doses of 0.3 mg and larger induced a growth retardation of the caudal morphogenetic systems (CMS). The administration of single effective doses of 1 subgerminally on the second day and intraamniotically on the third and fourth d of embryogenesis verified the beginning of the direct embryotoxicity range between the doses of 0.3 and 1 mg per embryo. It presents in the theoretical extrapolation for mammals the dose limits between 1 and 10 g.kg-1 of maternal weight. Embryotoxic manifestations (body wall defects, growth retardation and embryolethality) were induced predominantly in the embryos treated on d 2 with the very high doses only. Their frequency was rare. It has been concluded that 1 could be a safe potential natural drug carrier in clinical practice.

Animals↗

[The effect of a diet containing long-chain fatty acids on the formation of insoluble elastin in the rat aorta].

The paper deals with the influence of long-chain fatty acids on the formation of insoluble elastin in vivo. Oil isolated from the sea fish named flounder has been chosen as the source of those long-chain fatty acids. The diet containing the flounder oil was administered to pregnant rat females. The influence of fatty acids on the formation of insoluble elastin was evaluated according to the percentage changes of insoluble elastin in the aortas of newborn rats and to the changes of the amount of desmosine cross-links in isolated elastin. The administration of the diet with long-chain fatty acids causes no changes in the content of elastin in the aortas of the new-born rats, meanwhile the amount of desmosine increases considerably. The results on the aortas of new-born rats shown here are in good agreement with the changes on the aortas of 3-month-old rats published in a previous paper.

Animals↗

Changes of insoluble elastin in the rat aorta depending on isolation method.

The present paper brings data on quantitative and qualitative changes of insoluble elastin in the rat aorta depending on the used isolation method. In the content of desmosine crosslinks, so as in the accumulation of insoluble elastin in the aorta, considerable differences were found between the results obtained by means of the cyanogen bromide method and those determined in the samples after alkaline hydrolysis. It is underlined by the authors that these methodical differences must be taken into consideration whenever effects of various drugs on the formation of insoluble elastin and on the desmosine crosslinks are examined. Accumulation of insoluble elastin and formation of desmosine crosslinks in the rat aorta were found to be delayed as compared to the chicks. This, unlike the chicks, enables us to influence the formation of desmosine crosslinks in the rat even during the postnatal period.

Animals↗

Interaction of alpha-elastin with ionic detergents.

Coacervation is known to be a fundamental step in elastogenesis that is influenced by various naturally occurring substances in connective tissue. Therefore, interaction of alpha-elastin with ionic detergents (sodium dodecyl sulfate, dodecylbenzyldimethylammonium bromide, cetyltrimethylammonium bromide, pentadecacarbethoxytrimethylammonium bromide and cetylpyridinium bromide) was studied as a model for the elastin interaction with amphipilic substances. The course of the interactions was followed by the effect on thermal coacervation, solubilization of lipophilic dye, difference spectra measurements and fluorescence probe. The results indicate that the detergents examined interact with alpha-elastin below critical micelle concentration in two different ways. In the first case, a mixed micelle can be formed from the detergent molecules (SDS, DBD) and alpha-elastin: alternatively mixed micelles are not formed, but the detergent molecules (CT, PCT, CP) do interact with elastin. The interaction of alpha-elastin at the isoelectric point was found to depend more on the chemical structure of the detergent molecule than on its charge. If detergent concentrations above the critical micelle concentration were applied, the interaction mechanism was different from that observed at lower detergent concentration.

Animals↗

Influence of D-penicillamine on the formation of elastin and its cross-links.

The amount of insoluble elastin and its content of desmosine cross-links were investigated in aortas of chick embryos, to which D-penicillamine was administered on the 6th or 14th--16th day of incubation. D-Penicillamine was shown to alter the formation and maturation of elastin. Using lower doses (less than 50 mg) the weight of pooled aortic elastin is higher as compared with controls (related to 1 mg of elastin or to total weight of elastin). Increased isodesmosine:desmosine ratio in these samples indicates that this elastin is very young. On the other hand, a high dose of D-penicillamine (100 mg) decreased the content of elastin and also of its desmosine cross-links. The authors explain their findings by counteraction of two factors due to administration of penicillamine: the increased solubility of "insoluble elastin", and the decreased cross-link formation.

Amino Acids↗