Super-resolution (SR) microscopy is a cutting-edge method that can provide detailed structural information with high resolution. However, the thickness of the specimen has been a major limitation for SR methods, and large biological structures have posed a challenge. To overcome this, the key step is to optimise sample preparation to ensure optical homogeneity and clarity, which can enhance the capabilities of SR methods for the acquisition of thicker structures. Oocytes are the largest cells in the mammalian body and are crucial objects in reproductive biology. They are especially useful for studying membrane proteins. However, oocytes are extremely fragile and sensitive to mechanical manipulation and osmotic shocks, making sample preparation a critical and challenging step. We present an innovative, simple and sensitive approach to oocyte sample preparation for 3D STED acquisition. This involves alcohol dehydration and mounting into a high refractive index medium. This extended preparation procedure allowed us to successfully obtain a unique two-channel 3D STED SR image of an entire mouse oocyte. By optimising sample preparation, it is possible to overcome current limitations of SR methods and obtain high-resolution images of large biological structures, such as oocytes, in order to study fundamental biological processes. Lay Abstract: Super-resolution (SR) microscopy is a cutting-edge tool that allows scientists to view incredibly fine details in biological samples. However, it struggles with larger, thicker specimens, as they need to be optically clear and uniform for the best imaging results. In this study, we refined the sample preparation process to make it more suitable for SR microscopy. Our method includes carefully dehydrating biological samples with alcohol and then transferring them into a mounting medium that enhances optical clarity. This improved protocol enables high-resolution imaging of thick biological structures, which was previously challenging. By optimizing this preparation method, we hope to expand the use of SR microscopy for studying large biological samples, helping scientists better understand complex biological structures.
Autoři popisují případ 62leté ženy, která několik měsíců pozorovala na zadní straně pravého stehna asymptomatický kožní projev sestávající z mnohočetných tmavých drsných papul seskupených na malé ploše. Dermatoskopické a histologické vyšetření potvrdilo diagnózu naevus comedonicus. Práce uvádí přehled současných poznatků o tomto onemocnění.
Stationary papular keratotic plaque on the thigh – Nevus Comedonicus An asymptomatic keratotic skin lesion lasting several months developed on the thigh of a 62-year-old female. The plaque was composed of multiple dark rough papules grouped in a small area. Clinical, dermoscopic and histopathologic diagnosis of naevus comedonicus was established. The article presents an overview of current knowledge about this disability.
- Klíčová slova
- naevus comedonicus,
- MeSH
- dermatoskopie metody MeSH
- diferenciální diagnóza MeSH
- hamartom * diagnóza klasifikace patologie MeSH
- kožní nemoci diagnóza klasifikace patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- névus * diagnóza klasifikace patologie MeSH
- vlasový folikul patologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
This work illustrates a novel application of a supervised superpixel-based segmentation method for root micrograph classification and total fungal colonization rate estimation. Two procedures relying on successive classifier application on different root micrographs or on the same micrograph but with an increasing number of labels to be assigned to each picture element category are compared to a reference grid-intersect count method. Finally, supervised classification with at least 16 labels on the same picture appears as a convenient method for obtaining rapid and confident colonization rate estimates. We suggest this kind of method may be easily and routinely implemented for research or educational purposes.
OBJECTIVES: This study aimed to investigate the impact of bleaching agents based on carbamide or hydrogen peroxide on dental ceramics in vitro, utilizing scanning electron microscopy (SEM) and elemental analysis via inductively coupled plasma optical emission spectroscopy (ICP-OES). METHODS: CAD/CAM ceramics (IPS e.max®CAD, IPS Empress®CAD, Vitablocs® Mark II, Celtra Duo, and inCoris TZI) were treated with bleaching agents using either 10%, 20%, 30% carbamide peroxide or with 35%, and 40% hydrogen peroxide. RESULTS: Surface elemental release was not significantly affected by the type or concentration of bleaching agent (p>0.05). Ion release in feldspathic ceramics was significantly higher than in other ceramic materials (p⟨0.0001). Microstructural surface changes were observed in all materials except for lithium disilicate and zirconia-reinforced lithium silicate ceramics. CONCLUSIONS: All bleaching agents tested in this study showed a similar impact within each material type tested regarding total mass loss, elemental composition, or surface structure. CLINICAL RELEVANCE: Lithium disilicate and zirconia-reinforced lithium silicate ceramics were the most resistant to bleaching agents. In contrast, feldspathic ceramic showed the highest ion release and surface deterioration when exposed to all bleaching agents tested.
- MeSH
- design s pomocí počítače * MeSH
- karbamidperoxid * chemie MeSH
- keramika * chemie MeSH
- látky na bělení zubů * chemie MeSH
- mikroskopie elektronová rastrovací MeSH
- peroxid vodíku * chemie MeSH
- povrchové vlastnosti MeSH
- testování materiálů MeSH
- zirkonium chemie MeSH
- zubní porcelán * chemie MeSH
- Publikační typ
- časopisecké články MeSH
In the presented study, the cells of the glacial alga Ancylonema alaskanum collected in the Austrian Alps were analyzed. Algae were imaged both in their natural environment and in laboratory conditions using transmitted light and fluorescence microscopy. Using appropriate fluorochromes, the cell wall and cell organelles were studied. Oval nuclei located in the middle of the cell next to the chloroplasts and active mitochondria as well as lipid thylakoids of chloroplasts were imaged. Scanning electron microscopy showed that the surface of the algal cell wall was not significantly differentiated, and atomic force microscope imaging recorded little roughness. The SEM EDS analysis revealed that carbon, nitrogen, oxygen, and magnesium were the main components of the cells. It is worth emphasizing that the analyzed living algal cells were obtained directly from the glacier surface and demonstrated normal respiratory processes i.e. undisturbed physiological functions. Additionally, the mineral material accompanying the cells in their natural environment - fragments of the rock were imaged by Differential Interference Contrast microscopy and analyzed by Fourier Transform Infrared Spectroscopy. The study provides new data on the morphology and physicochemical characteristics of A. alaskanum, contributing to a more comprehensive characterization of their place in this harsh ecosystem.
- MeSH
- ledový příkrov * MeSH
- mikroskopie elektronová rastrovací MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Rakousko MeSH
Nedd4-2 E3 ligase regulates Na+ homeostasis by ubiquitinating various channels and membrane transporters, including the epithelial sodium channel ENaC. In turn, Nedd4-2 dysregulation leads to various conditions, including electrolytic imbalance, respiratory distress, hypertension, and kidney diseases. However, Nedd4-2 regulation remains mostly unclear. The present study aims at elucidating Nedd4-2 regulation by structurally characterizing Nedd4-2 and its complexes using several biophysical techniques. Our cryo-EM reconstruction shows that the C2 domain blocks the E2-binding surface of the HECT domain. This blockage, ubiquitin-binding exosite masking by the WW1 domain, catalytic C922 blockage and HECT domain stabilization provide the structural basis for Nedd4-2 autoinhibition. Furthermore, Ca2+-dependent C2 membrane binding disrupts C2/HECT interactions, but not Ca2+ alone, whereas 14-3-3 protein binds to a flexible region of Nedd4-2 containing the WW2 and WW3 domains, thereby inhibiting its catalytic activity and membrane binding. Overall, our data provide key mechanistic insights into Nedd4-2 regulation toward fostering the development of strategies targeting Nedd4-2 function.
- MeSH
- elektronová kryomikroskopie MeSH
- HEK293 buňky MeSH
- lidé MeSH
- molekulární modely MeSH
- proteinové domény MeSH
- proteiny 14-3-3 * metabolismus chemie MeSH
- ubikvitinace MeSH
- ubikvitinligasy Nedd4 * metabolismus chemie genetika ultrastruktura MeSH
- vápník * metabolismus MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
There is increasing pressure on meat producers worldwide due to the need for higher yields and improved meat quality. This is why anabolic androgenic steroids (AAS) have been widely used in most countries, due to their ability to accelerate animal muscle growth. However, out of concern for their side effects, EU states have banned their use and implemented control mechanisms. But they are reaching their limits, and therefore, it is necessary to look for new ways and investigate the mechanism of action of AAS on muscle tissue. This study replicated the administration of banned AAS (testosterone, nandrolone and their combination) and observed their effect on pig muscle. The pig model was purposely chosen for the study, as no such research has been carried out on this species. At the same time, pork is one of the most consumed meats in Europe. It focused on histological changes in muscle structure, specifically the size of muscle fibres and the number of satellite cells per muscle fibre. Furthermore, ultrastructural changes in muscle fibres, the diameter of myofibrils, the number of myofibrils per area, the distance between myofibrils and the size of sarcomeres were examined. The results using the techniques of histology, fluorescent labelling and transmission electron microscopy showed that, after the application of AAS, there is an increase in the diameter of muscle fibres, an increase in the diameter of myofibrils, a decrease in the number of myofibrils per surface area and, in the case of testosterone, an increase in the distance between myofibrils and an increase in the length of sarcomeres. There was also a significant increase in the number of satellite cells per muscle fibre. The detected statistically significant differences between control and experimental groups provide evidence that selected histological parameters could be additional mechanisms for detecting the presence of AAS in pork meat in the future.
- MeSH
- anabolika * farmakologie MeSH
- kosterní svalová vlákna * účinky léků ultrastruktura MeSH
- kosterní svaly účinky léků anatomie a histologie ultrastruktura MeSH
- myofibrily * účinky léků ultrastruktura MeSH
- nandrolon * farmakologie MeSH
- prasata anatomie a histologie MeSH
- sarkomery účinky léků ultrastruktura MeSH
- satelitní buňky kosterního svalu účinky léků ultrastruktura MeSH
- testosteron * farmakologie MeSH
- transmisní elektronová mikroskopie veterinární MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
160 stran : ilustrace ; 28 cm
Atlas, který se zaměřuje na anatomii lidského mozku, zobrazenou mikroskopicky, makroskopicky a pomocí magnetické rezonance. Určeno odborné veřejnosti.; Učebnice Řezy mozkem – nepostradatelný průvodce anatomickými detaily a diagnostickými metodami – spojuje makroskopické, mikroskopické a MRI řezy mozku do jednoho uceleného a systematického celku. Poskytuje jasné vizuální pochopení toho, jak mozek vypadá a jak jej lze interpretovat prostřednictvím moderních diagnostických metod, jejichž neustálý vývoj vyžaduje od studentů a lékařů, aby se orientovali nejen v zevní anatomii mozku, ale i v řezech. Vyšetření magnetickou rezonancí a výpočetní tomografií patří dnes mezi běžné metody a jednoznačným předpokladem k jejich interpretaci je znalost anatomie. Nejsrozumitelnější přístup k anatomii mozku – bohatá obrazová dokumentace umožňuje vidět mozek při pitvě nebo ve špičkově vybavené laboratoři. Ať už jde o frontální, transverzální nebo sagitální roviny, vše je zachyceno a doplněno přesnými schématy, která pomáhají pochopit polohu a orientaci jednotlivých řezů. Zdařilá kombinace teorie a praxe – text poskytuje vše, co je třeba pro interpretaci snímků z MRI nebo CT vyšetření, od makroskopické stavby až po mikroskopické detaily. Exkluzivní mikroskopické řezy – unikátní soubor mikroskopických řezů umožňuje porozumět hlavním strukturám, což pomáhá identifikaci jak pod mikroskopem, tak na diagnostických snímcích. Přehledná orientace díky současné anatomické nomenklatuře. Předpokladem k účelnému využití této publikace je základní znalost anatomie CNS, neboť atlas se soustředí výhradně na obrazovou dokumentaci. Kniha je určena studentům lékařství, neurologům, neuroradiologům, ale i dalším odborníkům, které fascinuje mozek a chtějí si rozšířit znalosti o jeho stavbě.
PURPOSE: To document the expression of apical-basal polarity (ABP) determinants in the mouse corneal epithelium (CE) and elucidate the functions of Pard3 in establishment and maintenance of ABP, stratification, homeostasis, and barrier function in the CE. METHODS: Pard3Δ/ΔC mice (Pard3LoxP/LoxP; Aldh3A1-Cre/+) with cornea-specific Pard3 ablation were generated by breeding Aldh3A1-Cre/+ with Pard3LoxP/LoxP mice. The control (Aldh3A1-Cre/+ or Pard3LoxP/LoxP alone) and Pard3Δ/ΔC corneal histology, ocular surface properties, barrier function, and actin cytoskeleton were assessed by Haematoxylin and Eosin staining of paraformaldehyde-fixed, paraffin-embedded tissues, scanning electron microscopy, fluorescein staining, and phalloidin staining, respectively. The expression of specific markers of interest was evaluated by qRT-PCR, immunoblots and immunofluorescent staining. RESULTS: Dynamic changes were observed in the expression and localization of ABP determinants as the CE stratified and matured between post-natal day 5 (PN5) and PN52. Adult Pard3Δ/ΔC CE contained fewer cell layers with rounded basal cells, and loosely adherent superficial cells lacking microplicae. Adult Pard3Δ/ΔC CE also displayed impaired barrier function with decreased expression of tight junction, adherens junction, and desmosome components, disrupted actin cytoskeletal organization, increased proliferation, and upregulation of transcription factors that drive epithelial-mesenchymal transition (EMT). CONCLUSIONS: Disruption of ABP in Pard3Δ/ΔC CE, altered expression of cell junction complex components and disorganized actin cytoskeleton, increased cell proliferation, and upregulated EMT transcription factors suggest that the ABP-determinant Pard3 promotes CE features while suppressing mesenchymal cell fate. Collectively, these results elucidate that Pard3-mediated ABP is essential for CE stratification, homeostasis and barrier function.
- MeSH
- adaptorové proteiny signální transdukční * MeSH
- cytoskelet * metabolismus MeSH
- homeostáza fyziologie MeSH
- mikroskopie elektronová rastrovací MeSH
- myši MeSH
- polarita buněk * fyziologie MeSH
- rohovkový epitel * metabolismus ultrastruktura MeSH
- těsný spoj * metabolismus fyziologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Rentgenová výpočetní mikrotomografie (mikroCT) představuje moderní zobrazovací technologii s vysokým rozlišením umožňující detailní analýzu zobrazovaného vzorku. Nabízí jedinečný pohled na trojrozměrnou architekturu díky rozlišení na pomezí makroskopického a histologického zobrazení. V oblasti anatomické patologie mikroCT nachází uplatnění zejména při morfometrické analýze nádorů, hodnocení resekčních okrajů chirurgických vzorků či detekci metastáz v lymfatických uzlinách. Kombinace mikroCT s tradičními histopatologickými technikami a s využitím digitální 3D rekonstrukce otevírá nové možnosti při analýze komplexních patologických procesů. Přestože je tato metoda zatím převážně využívána ve výzkumu, její klinický potenciál je značný. Mezi hlavní přednosti patří neinvazivní zobrazení a možnost integrace s digitální patologií a nástroji umělé inteligence. Hlavními limitacemi v současné době zůstávají potřeba kontrastování vzorků, monochromatická povaha obrazu a vysoká radiační zátěž. Pokrok v technologickém vývoji však může tyto překážky překonat a umožnit širší využití mikroCT v rutinní klinické diagnostice. Tento článek představuje technologii mikroCT a její diagnostický potenciál v patologii, přibližuje její aplikace, výhody a omezení, a nabízí vhled do budoucí perspektivy jejího využití.
X-ray microtomography (microCT) represents a modern high-resolution imaging technology enabling detailed analysis of the tissue. It offers a unique perspective on three-dimensional architecture, bridging the gap between macroscopic and histological imaging. In anatomical pathology, microCT is particularly utilized for morphometric tumor analysis, evaluation of surgical specimen resection margins, and detection of metastases in lymph nodes. The combination of microCT with traditional histopathological techniques, and with digital 3D reconstructions, opens new avenues for analyzing complex pathological processes. Although this method is currently used in research, its clinical potential is significant. Key advantages include non-invasive imaging and the ability to be integrated with digital pathology and artificial intelligence tools. Current limitations include the need for sample contrast enhancement, the monochromatic nature of the images, and high radiation exposure. Advances in technological development, however, may overcome these barriers and enable the broader adoption of microCT in routine clinical diagnostics. This article explores the diagnostic potential of microCT in pathology, highlighting its applications, advantages, and limitations, while offering insights into current capabilities and future perspectives of this technology.