- MeSH
- genetická predispozice k nemoci MeSH
- genetické poradenství MeSH
- genetické testování MeSH
- lidé MeSH
- nádory prsu * etiologie genetika MeSH
- nádory vaječníků * etiologie genetika MeSH
- profylaktická mastektomie MeSH
- rizikové faktory MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- přehledy MeSH
- Klíčová slova
- onkoplastická chirurgie, resekce nádoru,
- MeSH
- chirurgická onkologie * metody MeSH
- lidé MeSH
- mamoplastika metody MeSH
- mastektomie metody MeSH
- plastická chirurgie * metody MeSH
- Check Tag
- lidé MeSH
Effects of low-frequency electromagnetic fields (LF EMF) on the activation of different tissue recovery processes have already been fully understood. Preliminary recent data demonstrated that a special case of sinusoidal electromagnetic fields, known as amplitude-modulated currents (AMC) could have a potential to accelerate the cell metabolism or cell migration. An AMC generator was designed to generate sinusoidal induced electric currents with the amplitude modulation and the harmonic carrier frequency of 5,000 Hz was modulated by frequencies of 1 to 100 Hz. The magnetic field peak was 6 mT, electric field intensity 2 V/m and the current density of induced electrical currents was approximately 1 A/m(2). The coil of the generator was adapted to easy handling and safe integration into the shelf of the CO(2) incubator. The shelf with the coil was prepared for the introduction of cells in standard plastic in vitro chambers. The tests focused on cells with migratory capacity after injury or during immunological processes and thus, mesenchymal stromal cells (MSC), dendritic cells (DC), and fibroblasts were chosen. The tests involved exposures of the cells to LF EMF (180 min/day) every day, for a period of three days, before examining them for cell death, morphology changes, and CD markers. The samples were tested by using MTT assay and the effects on the intracellular concentration of reactive oxygen species were quantified. The cell migration was finally measured with the help of the transwell migration assay. None of the cell types showed any decrease in the cell viability after the LF EMF application and the cells displayed minimum changes in reactive oxygen species. Functional changes (acceleration of cell migration) after AMC exposure were statistically significant for the MSC samples only. The acceleration of MSCs is associated with the production of MMP by these cells. The EMF has a potential to be a safe, clinically applicable selective activator of MSC homing, MSC paracrine production, and subsequent regeneration processes.
- MeSH
- buňky 3T3 MeSH
- dendritické buňky fyziologie MeSH
- elektromagnetická pole * MeSH
- fibroblasty fyziologie MeSH
- lidé MeSH
- matrixová metaloproteinasa 2 metabolismus MeSH
- mezenchymální kmenové buňky fyziologie MeSH
- myši MeSH
- parakrinní signalizace MeSH
- pohyb buněk * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In the last few years, magnetically labeled cells have been intensively explored, and non-invasive cell tracking and magnetic manipulation methods have been tested in preclinical studies focused on cell transplantation. For clinical applications, it is desirable to know the intracellular pathway of nanoparticles, which can predict their biocompatibility with cells and the long-term imaging properties of labeled cells. Here, we quantified labeling efficiency, localization, and fluorescence properties of Rhodamine derivatized superparamagnetic maghemite nanoparticles (SAMN-R) in mesenchymal stromal cells (MSC). We investigated the stability of SAMN-R in the intracellular space during a long culture (20 days). Analyses were based on advanced confocal microscopy accompanied by atomic absorption spectroscopy (AAS) and magnetic resonance imaging. SAMN-R displayed excellent cellular uptake (24 h of labeling), and no toxicity of SAMN-R labeling was found. 83% of SAMN-R nanoparticles were localized in lysosomes, only 4.8% were found in mitochondria, and no particles were localized in the nucleus. On the basis of the MSC fluorescence measurement every 6 days, we also quantified the continual decrease of SAMN-R fluorescence in the average single MSC during 18 days. An additional set of analyses showed that the intracellular SAMN-R signal decrease was minimally caused by fluorophore degradation or nanoparticles extraction from the cells, main reason is a cell division. The fluorescence of SAMN-R nanoparticles within the cells was detectable minimally for 20 days. These observations indicate that SAMN-R nanoparticles have a potential for application in transplantation medicine.
- MeSH
- dextrany metabolismus MeSH
- fluorescenční spektrometrie MeSH
- intracelulární prostor metabolismus MeSH
- lidé MeSH
- magnetické nanočástice chemie MeSH
- mezenchymální kmenové buňky cytologie metabolismus MeSH
- molekulární sondy chemie metabolismus MeSH
- molekulární zobrazování metody MeSH
- rhodaminy chemie MeSH
- tuková tkáň cytologie MeSH
- viabilita buněk MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
2-Ethylhexyl methoxycinnamate (EHMC) is one of the most used ultraviolet filters in personal care products. It undergoes cis/trans isomerization in sunlight, and there is limited toxicological understanding of the effects of the cis-isomer. It is known that two geometric isomers of one compound can have different physico-chemical properties and effects. However, there are no studies focusing on toxicokinetics of EHMC isomerization products to compare their potential difference in dermal exposure to cis-EHMC and trans-EHMC due to the difference in their dermatotoxicokinetics. In this study, dermal absorption of the parental trans-EHMC and its cis isomer was studied. A commercially available sunscreen lotion containing trans-EHMC and spiked with laboratory-prepared cis-EHMC was locally applied on the forearm skin of two volunteers. After 8 h of skin exposure, the stratum corneum (SC) layer was removed by tape stripping. The removed thickness of the SC was determined spectrophotometrically using a total protein assay. The concentration of both isomers in the removed SC was measured by HPLC-DAD. A new diffusion and permeability coefficient of both EHMC isomers in SC were determined by Fick's second law of diffusion in vivo. The difference in dermatotoxicokinetic parameters between the two isomers was not statistically significant. However, separate toxicological studies of isomeric forms and the determination of their dermatotoxicokinetic parameters are crucial for refinement of human risk assessment.
- MeSH
- cinnamáty chemie farmakokinetika MeSH
- dospělí MeSH
- epidermis metabolismus MeSH
- kožní absorpce * MeSH
- lidé MeSH
- přípravky chránící proti slunci chemie farmakokinetika MeSH
- stereoizomerie MeSH
- toxikokinetika MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Due to their widespread usage, people are exposed to pesticides on a daily basis. Although these compounds may have adverse effects on their health, there is a gap in the data and the methodology needed to reliably quantify the risks of non-occupational human dermal exposure to pesticides. We used Franz cells and human skin in order to measure the dermal absorption kinetics (steady-state flux, lag time and permeability coefficient) of Carbendazim and Simazine. These parameters were then used to refine the dermal exposure model and a probabilistic simulation was used to quantify risks resulting from exposure to pesticide-polluted waters. The experimentally derived permeability coefficient was 0.0034 cm h(-1) for Carbendazim and 0.0047 cm h(-1) for Simazine. Two scenarios (varying exposure duration and concentration, i.e. environmentally relevant and maximum solubility) were used to quantify the human health risks (hazard quotients) for Carbendazim and Simazine. While no risks were determined in the case of either scenario, the permeability coefficient, which is concentration independent and donor, formulation, compound and membrane specific, may be used in other scenarios and exposure models to quantify more precisely the dermally absorbed dose during exposure to polluted water. To the best of our knowledge, the dermal absorption kinetics parameters defined here are being published for the first time. The usage of experimental permeability parameters in combination with probabilistic risk assessment thus provides a new tool for quantifying the risks of human dermal exposure to pesticides.
- MeSH
- benzimidazoly farmakokinetika MeSH
- biologické modely * MeSH
- dospělí MeSH
- hodnocení rizik MeSH
- karbamáty farmakokinetika MeSH
- kinetika MeSH
- kožní absorpce * MeSH
- kůže účinky léků metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- permeabilita MeSH
- pesticidy farmakokinetika MeSH
- simazin farmakokinetika MeSH
- techniky in vitro MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
