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The data from the first investigatiom of a new antioxidants family – peroxidoxins - in parasites. The properties and mechanism of action of a new family of antioxidants-peroxidoxins have been described. The properties of parasitic peroxidoxins in some helminths and protozoans discovered as a result of genom sequencing and expressed sequence tag (EST) project have been presented. The data described untill now from a number of studies with parasites indicate that the family of peroxidoxins, very important for the host-parasite interactions may be in future a potential candidate vaccine molecules in some systems.
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Punkty uchwytu leków przeciwpasożytniczych

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The main biochemical target points of some antiparasitic drugs were discussed; nucleic acids and carbohydrate metabolism being the targets for chemotherapeutic attack in Protozoa and microtubules and nervous systems - the targets in helminths.
The diagnostic value of same enzymatic biochemical tests in trichinellosis was evalued, the usefulness of LDH iso⁻⁴ and iso⁻⁵ quantitative estimations being especially stressed.
Contemporary methods of directed chemotherapy are based on multi-step procedures, which require co-ordinated activities of interdisciplinary teams of biochemists, pharmacologists, geneticists, crystallochemists as well as computer scientists. Biochemists select the proper target, such as an enzyme, througt screenig of the biochemical influence of compounds-potential drugs on this target. For further research they use targets with very low inhibition constans ( > 10⁻⁶ M). Determination of the relation between therapeutic activity of the compound and modelling of its chemical structure constitutes an important part of the procedure. The most important part of the procedure is the recognition of the primary structure of the target. The two following pathways allow to do that: 1. isolation of DNA and gDNA or cDNA-started cloning of a gene responsible for production of the target protein and then its sequencing, 2. purification and crystallization of the target protein and further computer-aided processing of crystallographic data in order to determine the primary structure. Computational chemistry (C/C) methods are the basic part of the procedure of molecular modelling (M/M) of a target molecule and its interactions with a molecule of the future drug. Data obtained using a technology which engages the C/C and M/M methods not only allow to determine the aminoacid sequence of the target protein in question (e.g. a unique parasite enzyme) they also enable to further speculate on its secondary and tertiary structures. Such structure includes specified number of repeated motifs of α-helixes, β-sheets and loops or turns. Particularly, the „barrel" structure is very common in numerous enzymes. Two following examples of research on target-antiparasitic drug interactions is presented. They are the interaction between phosphoglicerate kinase in Leishmania and drug suramin and malic enzyme of Trichinella and drug closantel. New promising targets for new anti-protozoan drugs (protozoa of Trypanosoma species) include e.g. microbody translocation signal in kinetosom proteins (SKL) or protein blocking the transport of proteins to glycosomes-metabolic centres in Trypanosoma (repetitive groups of QRLQ). Recently, scientists Crom Arris Pharmaceutical (San Francisco) have considered, employing new data, up to 100 to fully characterize the surface structure of a molecule, using the systems of artificial intelligence.
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Diagnostyka anisakidozy

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As the anisakiasis is considered a food-borne disease, the necessity of a proper diagnosis of human anisakiasis is accompanied by the proper diagnosis of fish anisakiasis, because the invaded fish meat may represent a potential source of Anisakis invasion for human. The authoress presents some problems of the diagnosis of human anisakiasis and the attempts of the development of efficient diagnostic methods for detecting fish anisakiasis. In view of the difficulties in parasitological diagnosis of human anisakiasis and the diagnosis based on the clinical findings, serodiagnosis would be potentially of a great value. From the available literature it appears, however that serological tests have not yielded a practical and totally reliable method for routine application. Just recently Desowitz et al., 1985 reported that radioallergosorbent test could serve as a useful techuiqne for the serodiagnosis of human anisakiasis. Their investigations needed however further confirmation on a greater group of the individuals with chronic anisakiasis. Current methods of identification of the Anisakis larvae based on the morphological features are difficult and time consuming. Biochemical analysis to identify unique parasite constituents (like ascaroides in Ascaris) are not successful. Enzyme linked immuno assay procedure have been developed, but the interference by the other substances in fish flesh could not be eliminated. Therefore the goal of the investigations presented recently (Boczoń and Bier, 1986) was to develop biochemical techniques for detecing Anisakis in seafood looking for a metabolic changes that occur in invaded fish host. Like in trichinellosis or fasciolosis the uncoupling of the invaded by Anisakis fish muscle mitochondria was observed. Dependent on the intensity of invasion there is a significant increase of mitochondrial Mg++ - stimulated ATP-ase activity in fish muscle mitochondria isolated from different species invaded by Anisakinae nematodes. This activity can be used to estimate the number of nematodes per market fish. Anisakis simplex excretory-secretory products, which in Boczoń and Bier in vitro experiments also caused the mitochondrial ATP-ase activity in coupled rat mitochondria to increase, were found to be a potent inhibitors of rodent lymphocyte blast transformation (Raybourne et al., 1983) and may contain components which are active in in vitro tests for potential tumor promoters (Raybourne, personal communication).
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Profesor Tadeusz Mazur [wspomnienie posmiertne]

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The mechanism of intracellular killing of pathogens which involves both oxygen and reactive nitrogen intermediates have been discussed. The attention is focused on inducible nitric oxide synthase which produces NO, a soluble free radical. The role of nitric synthase in the pathogenesis of many parasitic infections has recently been emphasised. The participation of enzymatic and non-enzymatic antioxidants in the pathogenesis of many infections and the role of proteasomes in the process of repair of the oxidetively damaged proteins are also discussed.
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