elektronický časopis
- Conspectus
- Lékařské vědy. Lékařství
- NML Fields
- biomedicínské inženýrství
- NML Publication type
- elektronické časopisy
Frozen aqueous solutions are an important subject of study in numerous scientific branches including the pharmaceutical and food industry, atmospheric chemistry, biology, and medicine. Here, we present an advanced environmental scanning electron microscope methodology for research of ice samples at environmentally relevant subzero temperatures, thus under conditions in which it is extremely challenging to maintain the thermodynamic equilibrium of the specimen. The methodology opens possibilities to observe intact ice samples at close to natural conditions. Based on the results of ANSYS software simulations of the surface temperature of a frozen sample, and knowledge of the partial pressure of water vapor in the gas mixture near the sample, we monitored static ice samples over several minutes. We also discuss possible artifacts that can arise from unwanted surface ice formation on, or ice sublimation from, the sample, as a consequence of shifting conditions away from thermodynamic equilibrium in the specimen chamber. To demonstrate the applicability of the methodology, we characterized how the true morphology of ice spheres containing salt changed upon aging and the morphology of ice spheres containing bovine serum albumin. After combining static observations with the dynamic process of ice sublimation from the sample, we can attain images with nanometer resolution.
The Extended Low Temperature Method (ELTM) for the in-situ preparation of plant samples in an environmental scanning electron microscope enables carrying out repetitive topographical and material analysis at a higher resolution in the vacuum conditions of a scanning electron microscope or in the low gas pressure conditions of an environmental scanning electron microscope. The method does not require any chemical intervention and is thus suitable for imaging delicate structures rarely observable with common treatment methods. The method enables both sample stabilization as close to their native state as possible, as well as the transfer of the same sample from a low vacuum to an atmospheric condition for sample storage or later study. It is impossible for wet samples in the environmental scanning electron microscope. Our studies illustrate the high applicability of the ELTM for different types of plant tissue, from imaging of plant waxes at higher resolution, the morphological study of highly susceptible early somatic embryos to the elemental microanalysis of root cells. The method established here provides a very fast, universal and inexpensive solution for plant sample treatment usable in a commercial environmental scanning electron microscope equipped with a cooling Peltier stage.
- MeSH
- Acute Disease MeSH
- Humans MeSH
- Traumatology MeSH
- Emergency Medicine organization & administration MeSH
- Emergency Medical Services organization & administration MeSH
- Check Tag
- Humans MeSH
- Geographicals
- Europe MeSH
This article describes the surface structure of Norway spruce early somatic embryos (ESEs) as a typical culture with asynchronous development. The microstructure of extracellular matrix covering ESEs were observed using the environmental scanning electron microscope as a primary tool and using the scanning electron microscope with cryo attachment and laser electron microscope as a complementary tool allowing our results to be proven independently. The fresh samples were observed in conditions of the air environment of the environmental scanning electron microscope (ESEM) with the pressure from 550Pa to 690Pa and the low temperature of the sample from -18°C to -22°C. The samples were studied using two different types of detector to allow studying either the thin surface structure or material composition. The scanning electron microscope with cryo attachment was used for imaging frozen extracellular matrix microstructure with higher resolution. The combination of both electron microscopy methods was suitable for observation of "native" plant samples, allowing correct evaluation of our results, free of error and artifacts.
AIMS: To measure the stigma of healthcare providers toward people suffering from mental illness, the Opening Minds Stigma Scale for Health Care Providers (OMS-HC) is a commonly applied instrument. However, this scale has not been thoroughly validated in many European countries, its psychometric properties are still unknown and data on practicing psychiatrists is lacking. Therefore, this multicenter study aimed to assess the psychometric characteristics of the 15-item OMS-HC in trainees and specialists in adult and child psychiatry in 32 countries across Europe. MATERIALS AND METHODS: The OMS-HC was conducted as an anonymous online survey and sent via Email to European adult and child psychiatrists. Parallel analysis was used to estimate the number of OMS-HC dimensions. Separate for each country, the bifactor ESEM, a bifactor exploratory structural equation modeling approach, was applied to investigate the factor structure of the scale. Cross-cultural validation was done based on multigroup confirmatory factor analyses and reliability measures. RESULTS: A total of 4,245 practitioners were included, 2,826 (67%) female, 1,389 (33%) male. The majority (66%) of participants were specialists, with 78% working in adult psychiatry. When country data were analyzed separately, the bifactor model (higher-order factor solution with a general factor and three specific factors) showed the best model fit (for the total sample χ2/df = 9.760, RMSEA = 0.045 (0.042-0.049), CFI = 0.981; TLI = 0.960, WRMR = 1.200). The average proportion of variance explained by the general factor was high (ECV = 0.682). This suggests that the aspects of 'attitude,' 'disclosure and help-seeking,' and 'social distance' could be treated as a single dimension of stigma. Among the specific factors, the 'disclosure and help-seeking' factor explained a considerable unique proportion of variance in the observed scores. CONCLUSION: This international study has led to cross-cultural analysis of the OMS-HC on a large sample of practicing psychiatrists. The bifactor structure displayed the best overall model fit in each country. Rather than using the subscales, we recommend the total score to quantify the overall stigmatizing attitudes. Further studies are required to strengthen our findings in countries where the proposed model was found to be weak.
- MeSH
- Child MeSH
- Adult MeSH
- Humans MeSH
- Attitude of Health Personnel * MeSH
- Psychometrics MeSH
- Reproducibility of Results MeSH
- Social Stigma * MeSH
- Health Personnel MeSH
- Check Tag
- Child MeSH
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
- Research Support, Non-U.S. Gov't MeSH
Nálezy částic kovů v patologicky změněných tkáních, jako jsou zánětlivé léze, nádory a jiné, vedly k myšlence, že mohou souviset se vznikem některých idiopatických chorob. Pro pochopení etiopatogeneze nemocí, spojených s přítomností nano- a mikročástic v organizmu, vznikla nová oblast patologie - nanopatologie. Četné výzkumy prokázaly, že nanočástice mohou vstupovat do lidského organizmu vdechováním nebo požitím. Průchodem přes plicní alveoly, kůži nebo střevní sliznici se dostávají do krve a lymfy, kdy jsou dále rozváděny do dalších orgánů. Existuje řada studií, ve kterých byl popsán negativní vliv ultrajemných částic na respirační a kardiovaskulární systém. Rovněž dochází k ukládání těchto částic v tkáních. Výzkumy také prokázaly, že některé nanočástice jsou schopny procházet póry jaderné membrány, kdy hrozí riziko poškození genetické informace buňky. Rovněž jsou schopny procházet přes hematoencefalickou a placentární bariéru. Nelze také opomenout jejich úlohu v indukci oxidativního stresu. Hlavním nástrojem k identifikaci těchto částic je skenovací elektronová mikroskopie s energiově disperzní spektroskopií (ESEM-EDS). Na základě tohoto vyšetření lze zjistit přibližnou velikost, morfologii a elementární složení částic. Chybí však metodika, která by umožnila kvantitativní hodnocení. Potenciál nanopatologie lze spatřovat v objasnění etiopatogeneze řady onemocnění a to nejenom respiračního, kardiovaskulárního, ale i řady dalších orgánových systémů.
The detection of metal particles in the pathologically altered tissues (eg. in inflammatory lesions or tumors) led to the idea that they might be associated with emergence of some idiopathic diseases. To understand the etiopathogenesis of diseases associated with the presence of nanoparticles in the tissue there is a new area of patology - nanopathology. Numerous studies have shown that nanoparticles can enter the human body through inhalation or ingestion. Through the pulmonary alveoli, skin and intestinal mucosa, the nanoparticles may reach the blood and lymphatic system, which subsequently distributes them to other target organs. Epithelial surfaces of conjunctiva and skin represent another potential way of penetration of nanoparticles into the body. There is a number of studies, which described the adverse effects of ultrafine particles on respiratory and cardiovascular system. Recent studies have also shown that some nanoparticles are able to pass through the pores of the nuclear membrane, where they may pose a risk of damage to cells and genetic information and they are also potentially capable to cross the placental and hematoencephalic barriers. Further, their role in the induction of oxidative stress is significant in relation to the mutagenesis. Scanning electron microscopy with energy disperse spectroscopy (SEM-EDS) represents a suitable tool for identification of metal-based particles in tissues and body fluids. Importance of nanopathogy can be seen in the elucidation of the etiopathogenesis of many diseases, not only of respiratory and cardiovascular systems, but also of many other organ systems.
- Keywords
- nemoci z nanočástic, ESEM-EDS,
- MeSH
- Metal Nanoparticles adverse effects MeSH
- Humans MeSH
- Microscopy, Electron, Scanning MeSH
- Nanoparticles * analysis adverse effects toxicity MeSH
- Nanomedicine * MeSH
- Nanostructures adverse effects therapeutic use MeSH
- Nanotechnology trends MeSH
- Disease * etiology MeSH
- Manufactured Materials adverse effects toxicity MeSH
- Environmental Exposure MeSH
- Environmental Pollution MeSH
- Check Tag
- Humans MeSH
- Publication type
- Review MeSH
