The ecotoxicological effect of after-usage released TiO2 nanoparticles in aquatic resources has been a major concern owing to their production and utilization in different applications. Addressing the issue, this study investigates the detailed in vivo molecular toxicity of TiO2 nanoparticles with Paramecium caudatum. TiO2 nanoparticles were synthesized at a lab scale using high energy ball milling technique; characterized for their physicochemical properties and investigated for their ecotoxicological impact on oxidative stress, steatosis, and apoptosis of cells through different biochemical analysis, flow cytometry, and fluorescent microscopy. TiO2 nanoparticles; TiO2 (N15); of size 36 ± 12 nm were synthesized with a zeta potential of - 20.2 ± 8.8 mV and bandgap of 4.6 ± 0.3 eV and exhibited a blue shift in UV-spectrum. Compared to the Bulk TiO2, the TiO2 (N15) exhibited higher cytotoxicity with a 24 h LC50 of 202.4 μg/ml with P. Caudatum. The mechanism was elucidated as the size and charge-dependent internalization of nanoparticles leading to abnormal physiological metabolism in oxidative stress, steatosis, and apoptosis because of their influential effect on the activity of metabolic proteins like SOD, GSH, MDA, and catalase. The study emphasized the controlled usage TiO2 nanoparticles in daily activity with a concern for ecological and biomedical aspects.
- MeSH
- apoptóza MeSH
- nanočástice * chemie toxicita MeSH
- oxidační stres MeSH
- Paramecium caudatum * MeSH
- titan toxicita MeSH
- Publikační typ
- časopisecké články MeSH
Nitric oxide (NO) chemistry inside the body is the most interesting part of its behavior. NO is involved in controlling blood pressure, and in transmitting nerve signals and a variety of other signaling processes. To explain the behavior of NO, it is necessary to determine its immediate concentration or observe time-dependent changes in its concentration. In Paramecium caudatum, NO is formed by calcium-dependent nNOS (NOS1)-like protein, which is distributed in the cytoplasm. NO synthesis affects the ciliary beat and consequent motility of cells and blocked NO synthesis reduces the ability of cells to move. The possibility of online coupling of microdialysis (of P. caudatum solution) with NO detection is demonstrated. Direct measurement of NO is carried out using dilute Bluestar® Forensic reagent (luminol-H2 O2 system; one of the NO detections is based upon the chemiluminescent reaction between NO and the luminol-H2 O2 system, which is specifically reactive to NO). The effect of a nitric oxide synthase inhibitor, NG-nitro-l-arginine methyl ester was observed. NO production was inhibited and the movement of P. caudatum was restricted. These effects were time dependent and after a specific time were reversed.
- MeSH
- inhibitory enzymů farmakologie MeSH
- luminiscenční měření MeSH
- luminol chemie MeSH
- mikrodialýza metody MeSH
- NG-nitroargininmethylester farmakologie MeSH
- oxid dusnatý analýza chemie metabolismus MeSH
- Paramecium caudatum chemie metabolismus MeSH
- peroxid vodíku chemie MeSH
- synthasa oxidu dusnatého antagonisté a inhibitory MeSH
- Publikační typ
- časopisecké články MeSH
Dispersal and the underlying movement behaviour are processes of pivotal importance for understanding and predicting metapopulation and metacommunity dynamics. Generally, dispersal decisions are condition-dependent and rely on information in the broad sense, like the presence of conspecifics. However, studies on metacommunities that include interspecific interactions generally disregard condition-dependence. Therefore, it remains unclear whether and how dispersal in metacommunities is condition-dependent and whether rules derived from single-species contexts can be scaled up to (meta)communities. Using experimental protist metacommunities, we show how dispersal and movement depend on and are adjusted by the strength of interspecific interactions. We found that the predicting movement and dispersal in metacommunities requires knowledge on behavioural responses to intra- and interspecific interaction strengths. Consequently, metacommunity dynamics inferred directly from single-species metapopulations without taking interspecific interactions into account are likely flawed. Our work identifies the significance of condition-dependence for understanding metacommunity dynamics, stability and the coexistence and distribution of species.
Predator and prey isoclines are estimated from data on yeast-protist population dynamics (Gause et al., 1936). Regression analysis shows that the prey isocline is best fitted by an L-shaped function that has a vertical and a horizontal part. The predator isocline is vertical. This shape of isoclines corresponds with the Lotka-Volterra and the Rosenzweig-MacArthur predator-prey models that assume a prey refuge. These results further support the idea that a prey refuge changes the prey isocline of predator-prey models from a horizontal to an L-shaped curve. Such a shape of the prey isocline effectively bounds amplitude of predator-prey oscillations, thus promotes species coexistence.
- MeSH
- biologické modely * MeSH
- Paramecium fyziologie MeSH
- predátorské chování * MeSH
- Schizosaccharomyces fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- Euglena fyziologie chemie MeSH
- fylogeneze MeSH
- kardiotonika chemie MeSH
- mikrobiologické jevy účinky léků MeSH
- molekulární struktura MeSH
- natriuretické peptidy fyziologie chemie MeSH
- organismy a jejich formy chemie klasifikace účinky léků MeSH
- osmotická diuretika MeSH
- osmóza fyziologie účinky léků MeSH
- Paramecium fyziologie chemie MeSH
- plazi MeSH
- rostliny MeSH
- ryby MeSH
Nanomaterials are now produced in large quantities due to their useful properties different from other materials. Possible toxicity of nanomaterials is currently addressed and discussed. Using a modified Tollens process, an aqueous dispersion of Ag nanoparticles was prepared, on which their unique properties and changes of material characteristics when approaching nano dimensions can be demonstrated. Also, experiments regarding toxicity of nanoparticles were proposed. Toxicity of the nanoparticles was tested on Paramecium caudatum. Following the instruction, the students discover that the prepared Ag nanoparticles are much less toxic than ionic Ag. The proposed experiments bring interdisciplinary chemical, physical, and biological findings and knowledge.
- MeSH
- antiinfekční látky toxicita MeSH
- chemické techniky analytické metody trendy výchova MeSH
- financování organizované MeSH
- koloidy chemie toxicita MeSH
- lidé MeSH
- mikrochemie metody výchova MeSH
- nanočástice mikrobiologie toxicita využití MeSH
- nanotechnologie metody trendy výchova MeSH
- Paramecium caudatum účinky léků MeSH
- přírodní vědy metody trendy výchova MeSH
- stříbro toxicita MeSH
- testy toxicity metody využití MeSH
- výchova a vzdělávání metody MeSH
- Check Tag
- lidé MeSH
Tetrahymena and Paramecium species are widely used representatives of the phylum Ciliata. Ciliates are particularly suitable model organisms for studying the functional heterogeneity of tubulins, since they provide a wide range of different microtubular structures in a single cell. Sequencing projects of the genomes of members of these two genera are in progress. Nearly all members of the tubulin superfamily (alpha-, beta-, gamma-, delta-, epsilon-, eta-, theta-, iota-, and kappa-tubulins) have been identified in Paramecium tetraurelia. In Tetrahymena spp., the functional consequences of different posttranslational tubulin modifications (acetylation, tyrosination and detyrosination, phosphorylation, glutamylation, and glycylation) have been studied by different approaches. These model organisms provide the opportunity to determine the function of tubulins found in ciliates, as well as in humans, but absent in some other model organisms. They also give us an opportunity to explore the mechanisms underlying microtubule diversity. Here we review current knowledge concerning the diversity of microtubular structures, tubulin genes, and posttranslational modifications in Tetrahymena and Paramecium species.
Many of the highly organized microtubular arrangements in ciliates are located in the cortical area containing membrane vesicles and vacuoles. In Tetrahymena thermophila and Paramecium caudatum, immunofluorescence microscopy with the monoclonal antibody TU-06, directed against beta-tubulin, revealed distinct staining of this cortical region alone, while the cilia and other microtubular structures were unstained. The specificity of the antibody was confirmed by immunoblotting and by preabsorption of the antibody with purified tubulin. Double-label immunofluorescence with antibodies against gamma-tubulin, detyrosinated alpha-tubulin, and centrin showed that the TU-06 epitope is localized outside the basal body region. This was also confirmed by immunogold electron microscopy of thin sections. Proteolytic digestion of porcine brain beta-tubulin combined with a peptide scan of immobilized, overlapping peptides disclosed that the epitope was in the beta-tubulin region beta81-95, a region which is phylogenetically highly conserved. As known posttranslational modifications of beta-tubulin are located outside this area, the observed staining pattern cannot be interpreted as evidence of subcellular sequestration of modified tubulin. The limited distribution of the epitope could rather reflect the dependence of TU-06 epitope exposition on conformations of tubulin molecules in microtubule arrangements or on differential masking by interacting proteins.
- MeSH
- buněčná membrána imunologie MeSH
- buňky 3T3 MeSH
- epitopy analýza imunologie metabolismus MeSH
- financování organizované MeSH
- imunoblotting MeSH
- mapování epitopu MeSH
- myši MeSH
- Paramecium imunologie MeSH
- Tetrahymena thermophila imunologie MeSH
- tubulin imunologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- MeSH
- buněčná membrána * MeSH
- fyziologie buňky MeSH
- Paramecium * MeSH
- regenerace MeSH
- RNA MeSH
- Publikační typ
- práce podpořená grantem MeSH
