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Ceramides are key components of the skin's permeability barrier. In atopic dermatitis, pathological hydrolysis of ceramide precursors - glucosylceramides and sphingomyelin - into lysosphingolipids, specifically glucosylsphingosine (GS) and sphingosine-phosphorylcholine (SPC), and free fatty acids (FFAs) has been proposed to contribute to impaired skin barrier function. This study investigated whether replacing ceramides with lysosphingolipids and FFAs in skin lipid barrier models would exacerbate barrier dysfunction. When applied topically to human stratum corneum sheets, SPC and GS increased water loss, decreased electrical impedance, and slightly disordered lipid chains. In lipid models containing isolated human stratum corneum ceramides, reducing ceramides by ≥ 30% significantly increased permeability to four markers, likely due to loss of long-periodicity phase (LPP) lamellae and phase separation within the lipid matrix, as revealed by X-ray diffraction and infrared spectroscopy. However, when the missing ceramides were replaced by lysosphingolipids and FFAs, no further increase in permeability was observed. Conversely, these molecules partially mitigated the negative effects of ceramide deficiency, particularly with 5%-10% SPC, which reduced permeability even compared to control with "healthy" lipid composition. These findings suggest that while ceramide deficiency is a key factor in skin barrier dysfunction, the presence of lysosphingolipids and FFAs does not aggravate lipid structural or functional damage, but may provide partial compensation, raising further questions about the behavior of lyso(sphingo)lipids in rigid multilamellar lipid environments, such as the stratum corneum, that warrant further investigation.
- MeSH
- biologické modely MeSH
- ceramidy * metabolismus MeSH
- fosforylcholin analogy a deriváty MeSH
- kůže * metabolismus MeSH
- kyseliny mastné neesterifikované metabolismus MeSH
- lidé MeSH
- lysofosfolipidy metabolismus MeSH
- permeabilita účinky léků MeSH
- sfingosin analogy a deriváty metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
TiO2 nanoparticles (NPs) are extensively used in various applications, highlighting the importance of ongoing research into their effects. This work belongs among rare whole-body inhalation studies investigating the effects of TiO2 NPs on mice. Unlike previous studies, the concentration of TiO2 NPs in the inhalation chamber (130.8 μg/m3) was significantly lower. This 11-week study on mice confirmed in vivo the presence of TiO2 NPs in lung macrophages and type II pneumocytes including their intracellular localization by using the electron microscopy and the state-of-the-art methods detecting NPs' chemical identity/crystal structure, such as the energy-dispersed X-ray spectroscopy (EDX), cathodoluminescence (CL), and detailed diffraction pattern analysis using powder nanobeam diffraction (PNBD). For the first time in inhalation study in vivo, the alterations in erythrocyte morphology with evidence of echinocytes and stomatocytes, accompanied by iron accumulation in spleen, liver, and kidney, are reported following NP's exposure. Together with the histopathological evidence of hyperaemia in the spleen and kidney, and haemosiderin presence in the spleen, the finding of NPs containing iron might suggest the increased decomposition of damaged erythrocytes. The detection of TiO2 NPs on erythrocytes through CL analysis confirmed their potential systemic availability. On the contrary, TiO2 NPs were not confirmed in other organs (spleen, liver, and kidney); Ti was detected only in the kidney near the detection limit.
- MeSH
- aplikace inhalační MeSH
- erytrocyty * účinky léků patologie MeSH
- inhalační expozice * škodlivé účinky MeSH
- kovové nanočástice * toxicita MeSH
- myši MeSH
- nanočástice * toxicita MeSH
- plíce * účinky léků metabolismus patologie MeSH
- testy subchronické toxicity MeSH
- titan * toxicita farmakokinetika aplikace a dávkování MeSH
- tkáňová distribuce MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Skin represents the largest organ in the human body, functioning as a protective barrier against environmental factors while playing a critical role in thermoregulation. Acne vulgaris is recognized as the most common dermatological condition affecting adolescents, and if left untreated, it can result in lasting skin damage and associated psychosocial challenges. This study aims to develop innovative polymeric biomaterials that could effectively support the treatment of acne vulgaris. The synthesis of these biomaterials involves the use of polyethylene glycol 6000, sodium alginate, and the antioxidant protein glutathione (GHS) to create polymeric hydrogels. These hydrogels were generated via a UV-mediated crosslinking process. To enhance the functional properties of the hydrogels, zinc oxide microparticles (ZnO), synthesized through a wet precipitation method, were incorporated into the formulations. Characterization of the ZnO was performed using Fourier-Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), particle sizer analysis, and Scanning Electron Microscopy (SEM). Additionally, the bioactivity of the synthesized materials was evaluated through incubation in media simulating physiological body fluids. The cytotoxic effects of the biomaterials were assessed using an indirect test on mouse fibroblast (L929) cells, in accordance with ISO 10993-5 guidelines. The results of our research indicate that the developed biomaterials exhibit potential as a carrier for active substances, contributing positively to the treatment of acne vulgaris and potentially improving overall skin health.
- MeSH
- acne vulgaris farmakoterapie MeSH
- algináty chemie MeSH
- biokompatibilní materiály chemie farmakologie MeSH
- buněčné linie MeSH
- fibroblasty účinky léků metabolismus MeSH
- glutathion * metabolismus MeSH
- hydrogely * chemie MeSH
- kůže * účinky léků metabolismus MeSH
- lidé MeSH
- myši MeSH
- nosiče léků chemie MeSH
- oxid zinečnatý * chemie farmakologie MeSH
- regenerace účinky léků MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The integration of 3D printing into the pharmaceutical sciences opens new possibilities for personalized medicine. Poly(lactide) (PLA), a biodegradable and biocompatible polymer, is highly suitable for biomedical applications, particularly in the context of 3D printing. However, its processability often requires the addition of plasticizers. This study investigates the use of phase diagram modeling as a tool to guide the rational selection of plasticizers and to assess their impact on the thermodynamic and kinetic stability of PLA-based amorphous solid dispersions (ASDs) containing active pharmaceutical ingredients (APIs). Thermodynamic stability against API recrystallization was predicted based on the API solubility in PLA and Plasticizer-PLA carriers using the Conductor-like Screening Model for Real Solvents (COSMO-RS), while the kinetic stability of the ASDs was evaluated by modeling the glass transition temperatures of the mixtures. Two APIs, indomethacin (IND) and naproxen (NAP), with differing glass-forming abilities (i.e., recrystallization tendencies), and three plasticizers, triacetin (TA), triethyl citrate (TEC), and poly(L-lactide-co-caprolactone) (PLCL), were selected for investigation. The physical stability of ASD formulations containing 9 wt% API and plasticizer to PLA in two ratios, 10:81 and 20:71 w/w %, was monitored over time using differential scanning calorimetry and X-ray powder diffraction and compared with phase diagram predictions. All formulations were predicted to be thermodynamically unstable; however, those containing no plasticizer or with TEC and TA at 10 wt% were predicted to exhibit some degree of kinetic stability. Long-term physical studies corroborated these predictions. The correlation between the predicted phase behavior and long-term physical stability highlights the potential of phase diagram modeling as a tool for the rational design of ASDs in pharmaceutical 3D printing.
- MeSH
- 3D tisk * MeSH
- citráty chemie MeSH
- diferenciální skenovací kalorimetrie metody MeSH
- farmaceutická chemie metody MeSH
- farmaceutická technologie metody MeSH
- indomethacin * chemie MeSH
- krystalizace MeSH
- naproxen chemie MeSH
- polyestery * chemie MeSH
- rozpouštědla chemie MeSH
- rozpustnost * MeSH
- stabilita léku MeSH
- termodynamika MeSH
- tranzitní teplota MeSH
- triacetin chemie MeSH
- změkčovadla * chemie MeSH
- Publikační typ
- časopisecké články MeSH
The vertebrate visual cycle hinges on enzymatically converting all-trans-retinol (at-ROL) into 11-cis-retinal (11c-RAL), the chromophore that binds to opsins in photoreceptors, forming light-responsive pigments. When struck by a photon, these pigments activate the phototransduction pathway and initiate the process of vision. The enzymatic isomerization of at-ROL, crucial for restoring the visual pigments and preparing them to receive new light stimuli, relies on various enzymes found in both the photoreceptors and retinal pigment epithelium cells. To function effectively, retinoids must shuttle between these two cell types. Retinol-binding protein 3 (RBP3), located in the interphotoreceptor matrix, probably plays a pivotal role in this transport mechanism. Comprised of four retinoid-binding modules, RBP3 also binds fatty acids, potentially aiding retinal function by facilitating the loading and unloading of different retinoids at specific cell types thereby directing the cycle. In this study, we present a 3.67 Å cryoEM structure of porcine RBP3, along with molecular docking analysis and corroborative in-solution small-angle X-ray scattering data for titration of RBP3 with relevant ligands, that also give insights on RBP3 conformational adaptability.
- MeSH
- difrakce rentgenového záření MeSH
- elektronová kryomikroskopie metody MeSH
- konformace proteinů MeSH
- maloúhlový rozptyl * MeSH
- molekulární modely MeSH
- oční proteiny MeSH
- prasata MeSH
- proteiny vázající retinol * chemie metabolismus MeSH
- simulace molekulového dockingu MeSH
- vazba proteinů MeSH
- vitamin A metabolismus chemie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The novel diiron amine complexes [Fe2Cp2(CO)(NH2R')(μ-CO){μ-CN(Me)(Cy)}]CF3SO3 [R' = H, 3; Cy, 4; CH2CH2NH2, 5; CH2CH2NMe2, 6; CH2CH2(4-C6H4OMe), 7; CH2CH2(4-C6H4OH), 8; Cp = η5-C5H5, Cy = C6H11 = cyclohexyl] were synthesized in 49-92 % yields from [Fe2Cp2(CO)2(μ-CO){μ-CN(Me)(Cy)}]CF3SO3, 1a, using a straightforward two-step procedure. They were characterized by IR and multinuclear NMR spectroscopy, and the structure of 7 was confirmed through X-ray diffraction analysis. Complexes 3-8 and the acetonitrile adducts [Fe2Cp2(CO)(NCMe)(μ-CO){μ-CN(Me)(R)}]CF3SO3 (R = Cy, 2a; Me, 2b; Xyl = 2,6-C6H3Me2, 2c) were assessed for their water solubility, octanol-water partition coefficient and stability in physiological-like solutions. The in vitro antiproliferative activity of 2a-c and 3-8 was tested on seven human cancer cell lines (A2780, A2780R, PC3, A549, MCF7, HOS and HT-29), while the selectivity was evaluated using normal MRC-5 cells. Overall, the complexes exhibited variable cytotoxicity, with IC50 values reaching the low micromolar range for 3, 7 and 8 in A2780 and A2780R cells, along with significant selectivity. Targeted experiments covered cell cycle modification, induction of cell death, mitochondrial membrane potential, ROS production and interaction with DNA and bovine serum albumin (BSA) as a model protein. The interaction of 3 with BSA was further investigated through computational studies. Results showed a negligible increase in intracellular ROS levels (except for 2b) and insignificant changes in mitochondrial membrane potential.
- MeSH
- aminy chemie farmakologie MeSH
- komplexní sloučeniny chemie farmakologie chemická syntéza MeSH
- lidé MeSH
- ligandy MeSH
- molekulární struktura MeSH
- nádorové buněčné linie MeSH
- proliferace buněk * účinky léků MeSH
- protinádorové látky * farmakologie chemie chemická syntéza MeSH
- screeningové testy protinádorových léčiv * MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- železo chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Ziziphora clinopodioides subsp. bungeana (Juz.) Rech.f. is used in traditional medicine for various purposes. Previous phytochemical studies focused on phenolic compounds, but triterpenoids were almost overlooked. OBJECTIVE: The study focused on the isolation of compounds with dual antidiabetic activity from the aerial parts of Z. clinopodioides subsp. bungeana. MATERIALS AND METHODS: Separation of CHCl3-soluble fraction by silica gel column chromatography using different mobile phases and purification of compounds by semi-preparative HPLC or preparative TLC. The structures of pure compounds were elucidated by 1D and 2D NMR experiments along with HRMS. Compound 1 was additionally identified by the single crystal X-ray diffraction method. α-Glucosidase inhibitory assay and GLUT4 expression and translocation in C2C12 myotubes were conducted to evaluate antidiabetic potential of isolated compounds. RESULTS: This phytochemical study led to the isolation of 20 compounds, including a unique monoterpene diperoxy dimer (1). Compounds 7 and 9-11 displayed more potent α-glucosidase inhibitory activity (IC50 45.3-135.3 μM) than acarbose used as a positive control (IC50 264.7 μM), while only pomolic acid (5) increased GLUT4 translocation in C2C12 myotubes in a significant manner. CONCLUSION: Extensive chromatographic separation led to the isolation and identification of a unique monoterpene diperoxy dimer (1) from aerial parts of Z. clinopodioides subsp. bungeana. Some triterpenes inhibited α-glucosidase, another increased GLUT4 translocation. Although none of the isolated compounds demonstrated dual antidiabetic activity, selected triterpenes proved to be potent antidiabetic agents in vitro.
- MeSH
- alfa-glukosidasy metabolismus MeSH
- buněčné linie MeSH
- hluchavkovité * chemie MeSH
- hypoglykemika * farmakologie chemie izolace a purifikace MeSH
- inhibitory glykosidových hydrolas farmakologie izolace a purifikace chemie MeSH
- myši MeSH
- nadzemní části rostlin chemie MeSH
- přenašeč glukosy typ 4 metabolismus MeSH
- rostlinné extrakty chemie farmakologie MeSH
- triterpeny * farmakologie chemie izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Free radical polymerization technique was used to formulate Poloxamer-188 based hydrogels for controlled delivery. A total of seven formulations were formulated with varying concentrations of polymer, monomer ad cross linker. In order to assess the structural properties of the formulated hydrogels, Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Scanning electron microscopy (SEM), and X-ray diffraction (XRD) were carried out. To assess the effect of pH on the release of the drug from the polymeric system, drug release studies were carried in pH 1.2 and 7.4 and it was found that release of the drug was significant in pH 7.4 as compared to that of pH 1.2 which confirmed the pH responsiveness of the system. Different kinetic models were also applied to the drug release to evaluate the mechanism of the drug release from the system. To determine the safety and biocompatibility of the system, toxicity study was also carried out for which healthy rabbits were selected and formulated hydrogels were orally administered to the rabbits. The results obtained suggested that the formulated poloxamer-188 hydrogels are biocompatible with biological system and have the potential to serve as controlled drug delivery vehicles.
- MeSH
- akrylové pryskyřice * chemie MeSH
- diferenciální skenovací kalorimetrie MeSH
- difrakce rentgenového záření MeSH
- hydrogely * chemie MeSH
- koncentrace vodíkových iontů MeSH
- králíci MeSH
- lékové transportní systémy MeSH
- léky s prodlouženým účinkem chemie farmakokinetika MeSH
- mikroskopie elektronová rastrovací MeSH
- nosiče léků chemie MeSH
- poloxamer * chemie MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- termogravimetrie MeSH
- timolol * aplikace a dávkování farmakokinetika chemie MeSH
- uvolňování léčiv MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Nanoparticles have drawn significant interest in a range of applications, ranging from biomedical to environmental sciences, due to their distinctive physicochemical characteristics. In this study, it was reported that simple biological production of Ag, Se, and bimetallic Ag2Se nanoparticles (NPs) with Pseudomonas aeruginosa is a promising, low-cost, and environmentally friendly method. For the first time in the scientific literature, Ag2Se nanoparticles have been generated via green bacterial biosynthesis. UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and EDX were used to characterize the produced NPs. Biosynthesized NPs were examined for antibacterial, antibiofilm, and photocatalytic properties, and it was determined that the effects of NPs were dose dependent. The biosynthesized AgNPs, SeNPs, and Ag2Se NPs showed anti-microbial activity against Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentrations (MICs) of E. coli and S. aureus were between 150 and 250 μg/mL. The NPs showed antibiofilm activity against E. coli and S. aureus at sub-MIC levels and reduced biofilm formation by at least 80% at a concentration of 200 μg/mL of each NPs. To photocatalyze the breakdown of Congo red, Ag, Se, and Ag2Se NPs were utilized, and their photocatalytic activity was tested at various concentrations and intervals. A minor decrease of photocatalytic degradation was detected throughout the NPs reuse operation (five cycles). Based on the encouraging findings, the synthesized NPs demonstrated antibacterial, antibiofilm, and photocatalytic properties, suggesting that they might be used in pharmaceutical, medical, environmental, and other applications.
- MeSH
- antibakteriální látky * farmakologie chemie chemická syntéza MeSH
- biofilmy * účinky léků MeSH
- Escherichia coli * účinky léků MeSH
- katalýza MeSH
- kovové nanočástice * chemie MeSH
- mikrobiální testy citlivosti * MeSH
- Pseudomonas aeruginosa * účinky léků metabolismus MeSH
- selen chemie farmakologie MeSH
- sloučeniny stříbra chemie farmakologie MeSH
- Staphylococcus aureus * účinky léků MeSH
- stříbro * chemie farmakologie metabolismus MeSH
- technologie zelené chemie * MeSH
- Publikační typ
- časopisecké články MeSH
Autoři v článku prezentují epidemiologii, rizikové faktory přispívající ke vzniku urolitiáz, věnují se dále laboratornímu vyšetření u litiatiků, včetně problematiky analýzy složení konkrementů a jeho významu. Hlavním cílem článku je předložení metod neinvazivní léčby jednotlivých typů litiázy, především metafylaxe u pacientů s litiázou, a to jak režimových opatřeních, tak i užití farmak, které přispívají ke snížení četností recidiv litiázy, ale i komplikacím, které jsou s tímto onemocněním spojené.
The authors present the epidemiology, risk factors contributing to the development of urolithiasis, laboratory examination in lithiatic patients, including the analysis of the composition of concrements and its significance. The main goal of the article is to present the methods of non-invasive treatment of different types of lithiasis, especially metaphylaxis in patients with lithiasis, both regimen measures and the use of drugs that contribute to reducing the frequency of recurrences of lithiasis, as well as complications associated with this disease
- MeSH
- alopurinol farmakologie terapeutické užití MeSH
- analýza moči metody MeSH
- cystinurie farmakoterapie komplikace MeSH
- difrakce rentgenového záření metody MeSH
- diuretika farmakologie terapeutické užití MeSH
- hydroxyapatit terapeutické užití MeSH
- hyperkalciurie farmakoterapie komplikace MeSH
- hyperoxalurie farmakoterapie komplikace MeSH
- hyperurikemie farmakoterapie komplikace MeSH
- infekce močového ústrojí etiologie komplikace MeSH
- kaliumcitrát farmakologie terapeutické užití MeSH
- kaménky etiologie klasifikace terapie MeSH
- klinické laboratorní techniky metody MeSH
- lidé MeSH
- oxaláty škodlivé účinky MeSH
- rizikové faktory MeSH
- urolitiáza * diagnóza farmakoterapie prevence a kontrola MeSH
- vápník dietní terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH