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The search for more effective drugs for the management of common hair growth disorders remains a top priority, both for clinical dermatology and industry. In this pilot study, we report a pragmatic organotypic assay for basic and applied hair research. The patented technique produces microdroplets, which generate human folliculoid microspheres (HFMs), consisting of human dermal papilla fibroblasts and outer root sheath keratinocytes within an extracellular matrix that simulates elements of the hair follicle mesenchyme. Studying a number of different markers (for example, proliferation, apoptosis, cytokeratin-6, versican), we show that these HFMs, cultured under well-defined conditions, retain several essential epithelial-mesenchymal interactions characteristic for human scalp hair follicle. Selected, recognized hair growth-modulatory agents modulate these parameters in a manner that suggests that HFMs allow the standardized preclinical assessment of test agents on relevant human hair growth markers under substantially simplified in vitro conditions that approximate the in vivo situation. Furthermore, we show by immunohistochemistry, reverse transcriptase-PCR, and DNA microarray techniques that HFMs also offer a useful discovery tool for the identification of target genes and their products for candidate hair drugs. HFM thus represent an instructive modern experimental and screening tool for basic and applied hair research in the human system.
- MeSH
- apoptóza MeSH
- cyklosporin farmakologie MeSH
- cytokiny genetika MeSH
- epitelové buňky cytologie MeSH
- financování organizované MeSH
- hepatocytární růstový faktor farmakologie MeSH
- kultivované buňky MeSH
- lidé MeSH
- mezibuněčná komunikace MeSH
- mezoderm cytologie MeSH
- mikrosféry MeSH
- proliferace buněk MeSH
- stanovení celkové genové exprese MeSH
- vlasový folikul cytologie růst a vývoj MeSH
- Check Tag
- lidé MeSH
The main task of the research is to acquire fundamental knowledge about the effect of polymer structure on the physicochemical properties of films. A novel meta-material that can be used in manufacturing sensor layers was developed as a model. At the first stage, poly(sodium 4-styrenesulfonate) (PNaSS) cross-linked microspheres are synthesized (which are based on strong polyelectrolytes containing sulfo groups in each monomer unit), and at the second stage, PNaSS@PEDOT microspheres are formed. The poly(3,4-ethylenedioxythiophene) (PEDOT) shell was obtained by the acid-assisted self-polymerization of the monomer; this process is biologically safe and thus suitable for biomedical applications. The suitability of electrochemical impedance spectroscopy for E. coli detection was tested; it was revealed that the attached bacterial wall was destroyed upon application of constant oxidation potential (higher than 0.5 V), which makes the PNaSS@PEDOT microsphere particles promising materials for the development of antifouling coatings. Furthermore, under open-circuit conditions, the walls of E. coli bacteria were not destroyed, which opens up the possibility of employing such meta-materials as sensor films. Scanning electron microscopy, X-ray photoelectron spectroscopy, water contact angle, and wide-angle X-ray diffraction methods were applied in order to characterize the PNaSS@PEDOT films.
- MeSH
- bicyklické sloučeniny heterocyklické chemie MeSH
- Escherichia coli * MeSH
- mikrosféry MeSH
- polymery * chemie MeSH
- Publikační typ
- časopisecké články MeSH
The aim of the study was to estimate possibilities of salt substitutes usage in the preparation of two sushi types (nigiri and maki) prepared with different seafood (salmon: Salmo salar, tuna: Thunnus albacares, and shrimp: Pleoticus muelleri). Potassium chloride (Mary samples), Soda-Lo (hollowed microsphere of regular salt crystals), and regular salt (sodium chloride) were used in the experiment. Sushi samples (n = 1960) were evaluated by 40 trained panelists who noticed that maki shrimp samples prepared with Mary salt had higher bitterness (21.48 ± 28.01) in comparison with 2% sodium chloride (7.91 ± 8.80). The saltiness was lower in nigiri tuna prepared with Mary (49.59 ± 17.47) than 2% sodium chloride (61.11 ± 15.75). The study clearly showed the possibility of lowering sodium content in sushi meal with the usage of salt substitutes, with emphasis that Soda-Lo should be considered as a better option due to the retention of sensory properties in sushi samples prepared with this salt substitute.
- MeSH
- chlorid draselný aplikace a dávkování chemie MeSH
- chlorid sodný MeSH
- kuchyňská sůl aplikace a dávkování analýza MeSH
- lidé MeSH
- mikrosféry * MeSH
- potrava z moře (živočišná) MeSH
- potravinářská technologie MeSH
- tuňák MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
DNA amplification by real-time polymerase chain reaction (RT-PCR) was used for the evaluation of efficiency of polymer coating of magnetic hydrophilic poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) (P(HEMA-co-GMA)) and poly(glycidyl methacrylate) (PGMA) microspheres with/without carboxyl groups. The inhibition effect of magnetic microspheres on real-time polymerase chain reaction (RT-PCR) course was evaluated by regression analysis after the addition of different concentrations of tested microspheres to PCR mixtures. Microspheres mostly did not interfere in RT-PCR till the concentration 50 µg/25 µl PCR mixture. No relationship between Fe content (and microsphere diameter) and inhibition effect was found. Microspheres containing carboxyl groups extinguished the fluorescence at lower concentrations (10-20 µg/25 µl PCR mixture) without inhibition of DNA amplification as PCR products were detected using agarose gel electrophoresis. Negative effect of maghemite on PCR course was partially reduced by coating of magnetic core by silica or polymers. Two inhibition mechanisms of DNA amplification were discussed in this work.
- MeSH
- DNA bakterií analýza genetika MeSH
- elektroforéza v agarovém gelu MeSH
- kvantitativní polymerázová řetězová reakce * MeSH
- kyseliny polymethakrylové chemie MeSH
- magnetické nanočástice chemie MeSH
- mikrosféry * MeSH
- molekulární patologie metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Alginátové mikrosféry s indomethacinem byly připraveny intovou gelací za použití chloridu vápenatého. Byl hodnocen vliv koncentrace chloridu vápenatého na velikost, enkapsulační účinnost a sféricitu připravených mikročástic. Bylo zjištěno, že změnou různých formulačních proměnných lze měnit enkapsulační účinnost i disoluční profil mikrosfér. Optimální in vitro disoluční profil indometacinu (podle USP specifikace s prodlouženým uvolňováním) byl dosažen ze vzorku obsahujícího 2 % natrium-alginátu a 2 % methylcelulosy tvrzeného v 3% roztoku chloridu vápenatého. Dle kinetického modelování disolučních dat byl Highuchi difuzní model vybrán jako vhodný. Dle FTIR studie nebyly potvrzeny žádné interakce mezi složkami mikročástic. DSC a XRD studie odhalily, že krystalinita léčiva inkorporovaného do mikročástic byla nižší ve srovnání s čistým léčivem. Farmakokinetické parametry byly získány na základě in vivo testů na králících s použitím HPLC techniky. Bylo zjištěno, že indomethacinové mikrosféry prokázaly vyšší t1/2 a AUC ve srovnání s indomethacinovou suspenzí. Jednoznačně bylo tedy prokázáno řízené uvolňování léčiva z mikrosfér, poskytující delší působení léčiva v terapeutickém rozmezí, které je výhodné zejména v léčbě chronických onemocnění.
Indomethacin-loaded alginate microspheres were prepared by the ionic cross linking technique using calcium chloride. The effect of calcium chloride concentration was evaluated with respect to the size, entrapment efficiency and shape (sphericity) of the particles. The entrapment efficiency and in vitro release profiles were found to be altered by changing various formulation parameters. The desired indomethacin in vitro release profile (as per USP specifications for extended release formulations) was obtained from microspheres prepared from gel containing 2% of sodium alginate and 2% of methyl cellulose hardened in 3% calcium chloride solution. The kinetic modeling of the release data indicated that indomethacin release from alginate microspheres followed Higuchi model and the release mechanism was diffusion. FTIR study confirmed the absence of any drug polymer interaction. DSC and XRD studies revealed that the crystallinity of the drug decreased when loaded in the alginate microspheres. The pharmacokinetic parameters were also evaluated in rabbits using HPLC technique and it was found that indomethacin loaded microspheres showed increased t1/2 and AUC values. Ke value was less than that of pure drug. This confirmed controlled release of the drug from microspheres leading to more residence time in the body within the therapeutic range providing longer duration of action which is preferable in chronic treatment of the diseases.
The efficient isolation and concentration of protein antigens from complex biological samples is a critical step in several analytical methods, such as mass spectrometry, flow cytometry and immunochemistry. These techniques take advantage of magnetic microspheres as immunosorbents. The focus of this study was on the development of new superparamagnetic polymer microspheres for the specific isolation of the tumor suppressor protein p53. Monodisperse macroporous poly(glycidyl methacrylate) (PGMA) microspheres measuring approximately 5 μm and containing carboxyl groups were prepared by multistep swelling polymerization of glycidyl methacrylate (GMA), 2-[(methoxycarbonyl)methoxy]ethyl methacrylate (MCMEMA) and ethylene dimethylacrylate (EDMA) as a crosslinker in the presence of cyclohexyl acetate as a porogen. To render the microspheres magnetic, iron oxide was precipitated within their pores; the Fe content in the particles received ∼18 wt%. Nonspecific interactions between the magnetic particles and biological media were minimized by coating the microspheres with poly(ethylene glycol) (PEG) terminated by carboxyl groups. The carboxyl groups of the magnetic PGMA microspheres were conjugated with primary amino groups of mouse monoclonal DO-1 antibody using conventional carbodiimide chemistry. The efficiency of protein p53 capture and the degree of nonspecific adsorption on neat and PEG-coated magnetic microspheres were determined by western blot analysis.
- MeSH
- kyseliny polymethakrylové chemie MeSH
- mikrosféry * MeSH
- myší monoklonální protilátky chemie MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádorový supresorový protein p53 chemie izolace a purifikace MeSH
- polyethylenglykoly chemie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
