Modification of the skin barrier properties. Permeation enhancers and the stratum corneum repair.

This dissertation aims to contribute to understanding the action mechanism of the skin permeation enhancers. It presents novel structure-activity relationship of the enhancers; hydrogen bonding ability, polar head size, chirality and the properties of the hydrophobic chains are discussed. Furthermore, a ceramide analogue effective in skin barrier repair was found. The common feature of these compounds is their site of action -skin barrier, particularly the stratum corneum ceramides. The skin barrier structure and function, including the recently proposed models of the barrier formation and molecular organisation are reviewed.Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi

Srovnání sací bublinky a bandáže pro analýzu epidermálních genů, bílkovin a lipidů

Analysis of epidermal genes, proteins and lipids is important in the research and diagnosis of skin diseases. Although punch biopsy is the first-choice technique for the skin sampling, it is unnecessarily invasive for obtaining a sample just for the epidermal analysis. Here we compare two less invasive methods, suction blistering (SB) and tape stripping (TS), for the analysis of selected epidermal genes (quantitative real-time reverse transcription PCR, qRT-PCR), proteins (western blotting, WB), and lipids in ten healthy volunteers. TS provided significantly less material than SB and no viable epidermal layers could be obtained according to the reflectance confocal microscopy. Consistently, only the SC protein filaggrin and housekeeping GAPDH together with FLG and RPL13A mRNA were detected by TS. In the SB samples, WB and qRT-PCR could easily detect all the selected proteins (claudin-1, occludin, filaggrin, laminin and GAPDH) and genes (CLDN1, OCLN, FLG, LAMA3 and RPL13A), respectively. A single SB sample further provided enough of material for immunohistochemistry and lipid analyses, which was not feasible with the TS samples. Immunohistochemistry of the SB samples showed intact epidermal structure and a characteristic expression of claudin-1. Infrared spectroscopy showed well-ordered lipids with both orthorhombic and hexagonal packing and high-performance thin layer chromatography confirmed all lipid classes (including ceramide subclasses) in correct proportions. Taken together, SB represents a reliable sampling technique that can be utilized for multipurpose epidermal analyses in various studies.Analýza epidermálních genů, proteinů a lipidů je důležitá při výzkumu a diagnostice kožních onemocnění. Ačkoli biopsie punch je metoda první volby pro vzorkování kůže, je zbytečně invazivní pro získání vzorku jen pro epidermální analýzu. Pro analýzu vybraných epidermálních genů (kvantitativní PCR reverzní transkripce v reálném čase, qRT-PCR), bílkoviny (Western blotting, WB) a srovnávací metody (SB) a strip stripping (TS) lipidů u deseti zdravých dobrovolníků. TS poskytovaly výrazně méně než SB a žádné životaschopné epidermální vrstvy nemohou být získány podle reflexní konfokální mikroskopie. Konzistentně byly TS detekovány pouze SC proteiny filaggrinu a housekeeping GAPDH společně s FLG a RPL13A mRNA. U vzorků SB by mohly WB a qRT-PCR snadno detekovat všechny vybrané proteiny (claudin-1, okluzin, filaggrin, laminin a GAPDH) a geny (CLDN1, OCLN, FLG, LAMA3 a RPL13A). Jeden vzorek SB dále poskytl dostatek materiálu pro imunohistochemické a lipidové analýzy, což nebylo možné u vzorků TS. Imunohistochemie vzorků SB ukázala intaktní epidermální strukturu a charakteristickou expresi claudinu-1. Infračervená spektroskopie ukázala dobře uspořádané lipidy s orthorhombickým a hexagonálním obalem a vysoce výkonná tenkovrstvá chromatografie potvrdila všechny třídy lipidů (včetně ceramidových podtřížek) ve správném poměru. Společně SB představuje spolehlivou metodu vzorkování, která může být použita pro víceúčelové epidermální analýzy v různých studiích

Development of 3,5-Dinitrobenzylsulfanyl-1,3,4-oxadiazoles and Thiadiazoles as Selective Antitubercular Agents Active Against Replicating and Nonreplicating Mycobacterium tuberculosis

Herein, we report the discovery and structure activity relationships of 5-substituted-2-[(3,5-dinitrobenzyl)-sulfanyl]-1,3,4-oxadiazoles and 1,3,4-thiadiazoles as a new class of antituberculosis agents. The majority of these compounds exhibited outstanding in vitro activity against Mycobacterium tuberculosis CNCTC My 331/88 and six multidrug-resistant clinically isolated strains of M. tuberculosis, with minimum inhibitory concentration values as low as 0.03 mu M (0.011-0.026 mu g/mL). The investigated compounds had a highly selective antimycobacterial effect because they showed no activity against the other bacteria or fungi tested in this study. Furthermore, the investigated compounds exhibited low in vitro toxicities in four proliferating mammalian cell lines and in isolated primary human hepatocytes. Several in vitro genotoxicity assays indicated that the selected compounds have no mutagenic activity. The oxadiazole and thiadiazole derivatives with the most favorable activity/toxicity profiles also showed potency comparable to that of rifampicin against the nonreplicating streptomycin-starved M. tuberculosis 18b-Lux strain, and therefore, these derivatives, are of particular interest