145 stran : ilustrace ; 30 cm
Směrnice, které se zaměřují na proces sterilizace zdravotnických prostředků pomocí páry a tepla. Určeno odborné veřejnosti.
- MeSH
- pára MeSH
- reprodukovatelnost výsledků MeSH
- řízení kvality MeSH
- sektor zdravotní péče MeSH
- sterilizace MeSH
- vysoká teplota MeSH
- zdravotnické prostředky MeSH
- Publikační typ
- směrnice MeSH
- Geografické názvy
- Česká republika MeSH
- Evropa MeSH
- Konspekt
- Metrologie. Standardizace
- NLK Obory
- technika lékařská, zdravotnický materiál a protetika
Dry skin is a common condition that is experienced by many. Besides being particularly present during the cold season, various diseases exist all year round, leading to localized xerosis. To prevent it, the skin is provided with natural moisturizing factors (NMFs). They are small amino acids or derivatives found in the outermost layer of the skin, the stratum corneum (SC). They are often claimed to be highly efficient humectants, increasing the water content to maintain the fluidity of the skin. However, alternative mechanisms have been proposed, suggesting that NMFs themselves may act as lipid mobility amplifiers. This work aims at investigating the role of three NMFs, namely, urea (URE), glycerol (GLY), and urocanic acid/urocanate (UCA/UCO) in SC in silico models, considering two different levels of humidity. Molecular dynamic simulations showed an increase in the diffusion of different lipid components, mainly free fatty acids (FFAs) and ceramide acyl chain moieties, in the presence of either high water content or NMFs. The membrane properties were modified, as seen by an increased thickness and greater lateral stiffness. All NMFs exhibited a similar impact, whereas UCA revealed slight differences according to its charged state. By studying NMF-water intermolecular interactions, we highlighted the role of NMF as a regulator of membrane perturbations while ensuring membrane fluidity. This role allows NMFs to prevent destabilization of the skin membrane in the presence of high water content. This study, performed at an atomistic resolution, highlighted a strong H-bond network between lipids involving mainly ceramides but also all other components. This network can be modified in the presence of a high water concentration or NMFs, resulting in modifications of membrane properties, rationalizing hydration effects.
- MeSH
- glycerol * chemie MeSH
- kůže * chemie metabolismus MeSH
- kyselina urokanová chemie metabolismus MeSH
- lidé MeSH
- močovina * chemie MeSH
- simulace molekulární dynamiky * MeSH
- voda * chemie MeSH
- vodíková vazba * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This study investigates the presence of perfluoroalkyl substances (PFAS) in the drinking water supplies in the Czech Republic using a risk-based monitoring approach. Tap water samples (n = 27) from sources close to areas potentially contaminated with PFAS were analysed. A total of 28 PFAS were measured using ultra-performance liquid chromatography with tandem mass spectrometry after solid phase extraction. Total PFAS concentrations (∑PFAS) varied from undetectable to 90.8 ng/L, with perfluoropentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA) and perfluorobutane sulfonic acid (PFBS) being the most abundant, detected in over 70% of samples. Risk-based monitoring in drinking water showed that commercial wells had higher PFAS levels compared to tap water, particularly C4-C9 perfluorocarboxylic acids (PFCAs), possibly due to proximity to industrial areas. However, the hypothesis that risk-based monitoring is more effective than random monitoring was not confirmed, possibly because specific sources did not produce the target PFAS or because of the wide range and less obvious sources of potential contamination. The study also assessed exposure risks and compliance with regulatory thresholds. Weekly intake estimates for adults and children indicated that regular consumption of most contaminated water sample would exceed the tolerable weekly intake. Compared to EU regulations, none of the tap water samples exceeded the 'Sum of PFAS' parametric value of 100 ng/L, though one sample approached this limit. In addition, surface water samples from the Jizera River (n = 21) showed a wider range of PFAS, with C7-C10 PFCAs, PFBS, and perfluorooctane sulfonic acid (PFOS) in every sample, with higher PFOS concentrations at a median of 2.56 ng/L. ∑PFAS concentrations increased downstream, rising from 1.08 ng/L near the spring to 26 ng/L downstream. This comprehensive analysis highlights the need for detailed/areal monitoring to also address hidden or non-obvious sources of PFAS contamination.
- MeSH
- chemické látky znečišťující vodu * analýza MeSH
- extrakce na pevné fázi MeSH
- fluorokarbony * analýza MeSH
- hodnocení rizik MeSH
- lidé MeSH
- monitorování životního prostředí * metody MeSH
- pitná voda * chemie MeSH
- tandemová hmotnostní spektrometrie MeSH
- vystavení vlivu životního prostředí analýza statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
In contrast to conventional diffusion magnetic resonance imaging (MRI), multi-b-value diffusion MRI methods are able to separate the signal from free water, pseudo-diffusion, and non-Gaussian components of water molecule diffusion. These approaches can then be utilised in so-called intravoxel incoherent motion imaging and diffusion kurtosis imaging. Various parameters provided by these methods can describe additional characteristics of the tissue microstructure and potentially help in the diagnosis and classification of various pathological processes. In this review, we present the basic principles and methods of analysing multi-b-value diffusion imaging data and specifically focus on the known possibilities for its use in the diagnosis of brain lesions. We also suggest possible directions for further research.
- MeSH
- difuzní magnetická rezonance * metody MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- mozek diagnostické zobrazování MeSH
- nemoci nervového systému * MeSH
- pohyb těles MeSH
- senzitivita a specificita MeSH
- voda MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Introduction: Rheumatoid arthritis (RA) is a chronic autoimmune disease with unknown cause. It mainly affects joints and, without proper treatment, negatively impacts their movement, causes painful deformities, and reduces the patients' quality of life. Current treatment options consist of various types of disease-modifying antirheumatic drugs (DMARDs), however 20-30% of patients are partially resistant to them. Therefore, development of new drugs is necessary. Possible option are compounds exhibiting their action via endocannabinoid system, which plays an important role in pain and inflammation modulation. One such compound - cannabidiol (CBD) has already been shown to attenuate synovitis in animal model of RA in in vivo studies. However, it has low bioavailability due to its low water solubility and lipophilicity. This issue can be addressed by preparation of a lipid containing formulation targeting lymphatic system, another route of absorption in the body. Materials and Methods: CBD-containing emulsion was prepared by high-shear homogenization and its droplet size distribution was analysed by optical microscopy. The relative oral bioavailability compared to oil solution as well as total availability of CBD were assessed in a cross-over study in rats and absorption of CBD via lymphatic system was observed. The effect of CBD on the animal model of RA was determined. Results: Compared to oil solution, the emulsion exhibited higher absolute oral bioavailability. Significant lymphatic transport of CBD was observed in all formulations and the concentrations in lymph were calculated. The therapeutic effect of CBD on RA was confirmed as an improvement in clinical symptoms as well as morphological signs of disease activity were observed during the study. Conclusion: In this work, we prepared a simple stable emulsion formulation, determined the pharmacokinetic parameters of CBD and calculated its absolute bioavailability in rats. Moreover, we successfully tested the pharmaceutical application of such a formulation and demonstrated the positive effect of CBD in an animal model of RA.
- MeSH
- aplikace orální MeSH
- bolest farmakoterapie MeSH
- emulze MeSH
- kanabidiol * farmakologie chemie MeSH
- klinické křížové studie MeSH
- krysa rodu rattus MeSH
- kvalita života MeSH
- revmatoidní artritida * farmakoterapie MeSH
- voda MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- dezinfekce MeSH
- lidé MeSH
- pití * MeSH
- pitná voda mikrobiologie zákonodárství a právo MeSH
- Check Tag
- lidé MeSH
Pružnosť ciev je významným rizikovým faktorom kardiovaskulárnych ochorení (KVO), ktoré sú najčastejšou príčinou úmrtí v rozvinutých krajinách. Na základe merania pružnosti ciev obyvateľov zásobovaných mäkkou pitnou vodou (100 respondentov) a tvrdou pitnou vodou (100 respondentov) bol zistený výrazný rozdiel v rýchlosti pulznej vlny (PWVao), arteriálneho veku a v rozdieli medzi arteriálnym a skutočným vekom (∆ vek). U respondentov, ktorí konzumovali mäkkú pitnú vodu, bola PWVao o 1,9 m.s−1 vyššia, arteriálny vek o 23,2 rokov vyšší a ∆ vek o 14,5 roka vyšší. Respondentom pôvodne konzumujúcim mäkkú pitnú vodu bol obsah Ca a Mg v pitnej vode zvýšený o približne 10–15 mg.l−1. Po 18 mesiacoch konzumácie obohatenej pitnej vody so zvýšeným obsahom Ca a Mg sa respondentom pôvodne konzumujúcim mäkkú pitnú vodu PWVao znížila o 0,93 m.s−1, arteriálny vek sa znížil o 10,42 roka a ∆ vek sa znížil o 11,79 roka. Veľmi výrazne sa im tak znížilo riziko vzniku KVO.
Arterial stiffness is a significant risk factor for cardiovascular diseases (CVD), which are the most common cause of death in developed countries. Based on measurements of arterial stiffness in inhabitants supplied with soft drinking water (100 respondents) and hard drinking water (100 respondents), a significant difference in pulse wave velocity (PWVao), arterial age, and the difference between arterial and actual age (Δ age) was found. In the respondents consuming soft drinking water, PWVao was 1.9 m.s-1 higher, arterial age was 23 years higher, and Δ age was 14.5 years higher. The respondents originally consuming soft drinking water, had the content of Ca and Mg in their water increased by approximately 10-15 mg.l-1. After 18 months of consuming enriched drinking water with increased Ca and Mg content, PWVao in the respondents originally consuming soft drinking water decreased by 0.93 m.s-1, arterial age decreased by 10.42 years, and Δ age decreased by 11.79 years. Their risk of developing CVD thus decreased significantly.
- MeSH
- hořčík MeSH
- kardiovaskulární nemoci prevence a kontrola MeSH
- klinická studie jako téma MeSH
- lidé MeSH
- pitná voda * analýza MeSH
- tuhost cévní stěny MeSH
- vápník dietní MeSH
- Check Tag
- lidé MeSH
- Geografické názvy
- Slovenská republika MeSH
Long-term peritoneal dialysis is associated with the development of peritoneal membrane alterations, both in morphology and function. Impaired ultrafiltration (UF) is the most important functional change, and peritoneal fibrosis is the major morphological alteration. Both are caused by the continuous exposure to dialysis solutions that are different from plasma water with regard to the buffer substance and the extremely high-glucose concentrations. Glucose has been incriminated as the major cause of long-term peritoneal membrane changes, but the precise mechanism has not been identified. We argue that glucose causes the membrane alterations by peritoneal pseudohypoxia and by the formation of advanced glycosylation end products (AGEs). After a summary of UF kinetics including the role of glucose transporters (GLUT), and a discussion on morphologic alterations, relationships between function and morphology and a survey of the pathogenesis of UF failure (UFF), it will be argued that impaired UF is partly caused by a reduction in small pore fluid transport as a consequence of AGE-related vasculopathy and - more importantly - in diminished free water transport due to pseudohypoxia, caused by increased peritoneal cellular expression of GLUT-1. The metabolism of intracellular glucose will be reviewed. This occurs in the glycolysis and in the polyol/sorbitol pathway, the latter is activated in case of a large supply. In both pathways the ratio between the reduced and oxidised form of nicotinamide dinucleotide (NADH/NAD+ ratio) will increase, especially because normal compensatory mechanisms may be impaired, and activate expression of hypoxia-inducible factor-1 (HIF-1). The latter gene activates various profibrotic factors and GLUT-1. Besides replacement of glucose as an osmotic agent, medical treatment/prevention is currently limited to tamoxifen and possibly Renin/angiotensis/aldosteron (RAA) inhibitors.
- MeSH
- dialyzační roztoky škodlivé účinky metabolismus MeSH
- glukosa škodlivé účinky metabolismus MeSH
- glykosylace MeSH
- lidé MeSH
- peritoneální dialýza * škodlivé účinky MeSH
- peritoneum metabolismus MeSH
- ultrafiltrace MeSH
- voda metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Klíčová slova
- metoda REZUM,
- MeSH
- hyperplazie prostaty * chirurgie MeSH
- indukovaná hypertermie MeSH
- lidé MeSH
- miniinvazivní chirurgické výkony MeSH
- pára MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
