Structured light technology
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The GPCR signalling cascade is a key pathway responsible for the signal transduction of a multitude of physical and chemical stimuli, including light, odorants, neurotransmitters and hormones. Understanding the structural and functional properties of the GPCR cascade requires direct observation of signalling processes in high spatial and temporal resolution, with minimal perturbation to endogenous systems. Optical microscopy and spectroscopy techniques are uniquely suited to this purpose because they excel at multiple spatial and temporal scales and can be used in living objects. Here, we review recent developments in microscopy and spectroscopy technologies which enable new insights into GPCR signalling. We focus on advanced techniques with high spatial and temporal resolution, single-molecule methods, labelling strategies and approaches suitable for endogenous systems and large living objects. This review aims to assist researchers in choosing appropriate microscopy and spectroscopy approaches for a variety of applications in the study of cellular signalling. LINKED ARTICLES: This article is part of a themed issue Complexity of GPCR Modulation and Signaling (ERNST). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.14/issuetoc.
- MeSH
- lidé MeSH
- mikroskopie * metody MeSH
- receptory spřažené s G-proteiny * chemie metabolismus MeSH
- signální transdukce MeSH
- spektrální analýza * metody MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
A series of new indole-pyrazole hybrids 8a-m were synthesized through the palladium-catalyzed ligandless Heck coupling reaction from easily accessible unsubstituted, methoxy- or fluoro-substituted 4-ethenyl-1H-pyrazoles and 5-bromo-3H-indoles. These compounds exerted cytotoxicity to melanoma G361 cells when irradiated with blue light (414 nm) and no cytotoxicity in the dark at concentrations up to 10 μM, prompting us to explore their photodynamic effects. The photodynamic properties of the example compound 8d were further investigated in breast cancer MCF-7 cells. Evaluation revealed comparable anticancer activities of 8d in both breast and melanoma cancer cell lines within the submicromolar range. The treatment induced a massive generation of reactive oxygen species, leading to different types of cell death depending on the compound concentration and the irradiation intensity.
- MeSH
- fotochemoterapie * MeSH
- fotosenzibilizující látky * farmakologie chemická syntéza chemie MeSH
- indoly * farmakologie chemie chemická syntéza MeSH
- lidé MeSH
- MFC-7 buňky MeSH
- molekulární struktura MeSH
- nádorové buněčné linie MeSH
- nádory prsu farmakoterapie patologie MeSH
- palladium chemie farmakologie MeSH
- protinádorové látky * farmakologie chemická syntéza chemie MeSH
- pyrazoly * farmakologie chemická syntéza chemie MeSH
- reaktivní formy kyslíku * metabolismus MeSH
- viabilita buněk účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Assessment of the posterior lateral knee pain poses diagnostic challenges, requiring accurate evaluation of various structures in light of the medical history and physical examination. Despite substantial progress in the ultrasonographic diagnosis of musculoskeletal disorders, the current protocol (EURO-MUSCULUS/USPRM. Basic scanning protocols for knee) fails to conduct a comprehensive investigation into the intricate, tendons, and ligaments of the posterior lateral knee. This pictorial review aims to bridge this gap by offering a systematic approach to utilize ultrasound examination of the less-discussed structures in this specific region. Providing cadaveric and magnetic resonance images, this essay demonstrates the efficacy of ultrasound in diagnosing posterior lateral knee pain. Notably, pathologies such as ligamentous sprains and tears are clearly discernible. Moreover, the integration of ultrasound guidance plays a vital role in reducing the risk of inadvertent neurovascular injury during injection, such as the common peroneal nerve and lateral genicular artery. This comprehensive approach will enhance clinicians' understanding and equip them with effective management strategies for posterior lateral knee pain.Critical relevance statement In this visual exposition, we delve into the intricacies of the posterior lateral corner of the knee. Offering a methodical approach to employ ultrasound for visualization of the less-explored structures within this region, the authors aim to enhance the diagnosis in posterior lateral knee pain.Key points1. Ultrasound excels at revealing intricate structures in the posterior lateral knee.2. Due to proximity of vital structures, extreme caution is crucial during injections.3. Employing dynamic scan and understanding ligaments enables a comprehensive exploration of pathologies.
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
SIGNIFICANCE: Over more than 300 years, microscopic imaging keeps providing fundamental insights into the mechanisms of living organisms. Seeing microscopic structures beyond the reach of free-space light-based microscopy, however, requires dissection of the tissue-an intervention seriously disturbing its physiological functions. The hunt for low-invasiveness tools has led a growing community of physicists and engineers into the realm of complex media photonics. One of its activities represents exploiting multimode optical fibers (MMFs) as ultra-thin endoscopic probes. Employing wavefront shaping, these tools only recently facilitated the first peeks at cells and their sub-cellular compartments at the bottom of the mouse brain with the impact of micro-scale tissue damage. AIM: Here, we aim to highlight advances in MMF-based holographic endo-microscopy facilitating microscopic imaging throughout the whole depth of the mouse brain. APPROACH: We summarize the important technical and methodological prerequisites for stabile high-resolution imaging in vivo. RESULTS: We showcase images of the microscopic building blocks of brain tissue, including neurons, neuronal processes, vessels, intracellular calcium signaling, and red blood cell velocity in individual vessels. CONCLUSIONS: This perspective article helps to understand the complexity behind the technology of holographic endo-microscopy, summarizes its recent advances and challenges, and stimulates the mind of the reader for further exploitation of this tool in the neuroscience research.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: During the worldwide COVID-19 pandemic crisis, the role of digital contact tracing (DCT) intensified. However, the uptake of this technology expectedly differed among age cohorts and national cultures. Various conceptual tools were introduced to strengthen DCT research from a theoretical perspective. However, little has been done to compare theory-supported findings across different cultural contexts and age cohorts. OBJECTIVE: Building on the original study conducted in Belgium in April 2020 and theoretically underpinned by the Health Belief Model (HBM), this study attempted to confirm the predictors of DCT adoption in a cultural environment different from the original setting, that is, the Czech Republic. In addition, by using brief qualitative evidence, it aimed to shed light on the possible limitations of the HBM in the examined context and to propose certain extensions of the HBM. METHODS: A Czech version of the original instrument was administered to a convenience sample of young (aged 18-29 y) Czech adults in November 2020. After filtering, 519 valid responses were obtained and included in the quantitative data analysis, which used structural equation modeling and followed the proposed structure of the relationships among the HBM constructs. Furthermore, a qualitative thematic analysis of the free-text answers was conducted to provide additional insights about the model's validity in the given context. RESULTS: The proposed measurement model exhibited less optimal fit (root mean square error of approximation=0.065, 90% CI 0.060-0.070) than in the original study (root mean square error of approximation=0.036, 90% CI 0.033-0.039). Nevertheless, perceived benefits and perceived barriers were confirmed as the main, statistically significant predictors of DCT uptake, consistent with the original study (β=.60, P<.001 and β=-.39; P<.001, respectively). Differently from the original study, self-efficacy was not a significant predictor in the strict statistical sense (β=.12; P=.003). In addition, qualitative analysis demonstrated that in the given cohort, perceived barriers was the most frequent theme (166/354, 46.9% of total codes). Under this category, psychological fears and concerns was a subtheme, notably diverging from the original operationalization of the perceived barriers construct. In a similar sense, a role for social influence in DCT uptake processes was suggested by some respondents (12/354, 1.7% of total codes). In summary, the quantitative and qualitative results indicated that the proposed quantitative model seemed to be of limited value in the examined context. CONCLUSIONS: Future studies should focus on reconceptualizing the 2 underperforming constructs (ie, perceived severity and cues to action) by considering the qualitative findings. This study also provided actionable insights for policy makers and app developers to mitigate DCT adoption issues in the event of a future pandemic caused by unknown viral agents.
- MeSH
- COVID-19 * epidemiologie MeSH
- lidé MeSH
- mladiství MeSH
- mobilní aplikace * MeSH
- pandemie MeSH
- srovnání kultur MeSH
- trasování kontaktů metody MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
OBJECTIVES: A stent is a mesh tube inserted into a natural passage in the body to prevent disease induction. Self-expandable esophageal nitinol stents such as SX-ELLA Stent Esophageal HV (HV Stent Plus) can be indicated for palliation of malignant esophageal strictures, for the treatment of benign esophageal strictures that are refractory to standard therapy and for the treatment of esophago-respiratory fistulas. A silicone-stent coating is used for tumor in-growth prevention and esophago-respiratory fistula occlusion. The thickness of the stent and the overall integrity of the silicone coating of all wires indicate the overall mechanical properties of the esophageal stent and the resistance to external adverse events such as corrosion and mechanical and chemical resistance. METHODS: The polymer multicomponent epoxy resin - a mixture of Epon and Durcupan - was used as a method for robust sample stabilization. A cutting system using a thin water beam with a powder (Blue Line) was chosen as the best variant to obtain 6 samples for both-sided measurement (10 measuring sides). The optical microscopic reflective light method was used to examine wire crossing points in the sections. Fifty values were measured on either sample side for the internal, external and mesh thickness of the silicone stent layer. The wire crossing points were selected so that the silicone layer structure could be clearly seen, and the wires approached each other most closely. Only approximately 4 to 8 crossing points in each section could be measured when applying this approach. The resolution of the microscope and calibration (based on the camera used) was 0.677 μm/pixel. RESULTS: Additional data could be obtained on 8 planes. Two boundary samples were destroyed by the cutting process. Whole coating of the stent was around all mesh wires, especially in areas with higher mechanical stress (wire crossing). The minimum detectable and admissible value determined for all 3 measuring areas (internal, external, mesh) on the wire crossings was 6.77 μm, i.e., 10 pixels, based on the microscope resolution and manufacturer's methodology. The results were characterized by p < 0.001 for all 3 parameters. We tested opposite samples in each section to verify the section quality and data consistency. For the 4 areas, the data were significantly different, but the thickness differences were only on the order of units percent, so the measurements were not appreciably affected. We assume that the material cutting loss, making up 1-2 mm, contributed to the differences in the sections. CONCLUSION: We examined the overall integrity of the silicone coating of the esophageal stent. The method of HV stent anchoring in a polymeric bath followed by cutting with a waterjet and sample measurement under an optical microscope proved to be very simple and reliable. Sufficient thicknesses of the silicone layer on the wire cross sections were verified. The coated silicone layer thickness appeared to be significantly different along the stent from the proximal part to the distant part, presumably due to the manufacturing technology.
Multispectral imaging is used in various applications including astronomy, industry and agriculture. In retinal imaging, the single-shot multispectral image stack is typically acquired and analyzed. This multispectral analysis can provide information on various structural or metabolic properties. This paper describes the multispectral improvement of a video-ophthalmoscope, which can acquire retinal video sequences of the optic nerve head and peripapillary area using various spectral light illumination. The description of the multispectral video imaging is provided and several applications are described. These applications include multispectral retinal photoplethysmography, visualization of spontaneous vein pulsation and multispectral RGB image generation.
With the development of light microscopy, it is becoming increasingly easy to obtain detailed multicolor fluorescence volumetric data. The need for their appropriate visualization has become an integral part of fluorescence imaging. Virtual reality (VR) technology provides a new way of visualizing multidimensional image data or models so that the entire 3D structure can be intuitively observed, together with different object features or details on or within the object. With the need for imaging advanced volumetric data, demands for the control of virtual object properties are increasing; this happens especially for multicolor objects obtained by fluorescent microscopy. Existing solutions with universal VR controllers or software-based controllers with the need to define sufficient space for the user to manipulate data in VR are not usable in many practical applications. Therefore, we developed a custom gesture-based VR control system with a custom controller connected to the FluoRender visualization environment. A multitouch sensor disk was used for this purpose. Our control system may be a good choice for easier and more comfortable manipulation of virtual objects and their properties, especially using confocal microscopy, which is the most widely used technique for acquiring volumetric fluorescence data so far.
- MeSH
- gesta * MeSH
- konfokální mikroskopie MeSH
- software MeSH
- virtuální realita * MeSH
- Publikační typ
- časopisecké články MeSH
The article deals with the possible influence of an extremely low-frequency magnetic field on cellular structures. The work is carried out to verify the change of growth dynamics of exposed samples by application of a time-varying magnetic field, with a specified action value of magnetic flux density, valid in the European Union. The frequency of applied field was preliminarily confirmed as biologically active, under conditions for Ion Parametric Resonance theory, in experimental work focused on targeting Ca2+ ions bound in specific positions on cellular membranes of eukaryotic cells. In thirty experiments, the authors use the dynamics of growth over a time horizon of eight hours to elucidate the effect of the field on the proliferation activity of the cells. Since living beings are exposed to similar electromagnetic fields daily, the presented article shed some light on whether, or not the irradiation has brought a statistically significant effect under conditions specified in ICNIRP guidelines and recommendations.
- MeSH
- biomedicínské technologie metody MeSH
- biomedicínský výzkum metody MeSH
- elektromagnetická pole škodlivé účinky MeSH
- kvasinky účinky záření MeSH
- magnetické pole * škodlivé účinky MeSH
- radiační expozice škodlivé účinky MeSH
- Saccharomyces cerevisiae růst a vývoj účinky záření MeSH
- vystavení vlivu životního prostředí prevence a kontrola škodlivé účinky MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
... Parvin -- Introduction, 2 Atomic Structure, 2 Particles, 2 -- The Atom and the Nucleus, 3 The Forces, ... ... Paramagnetic Resonance Dosimetry, 44 Biological Dosimetry, 45 Biological Molecules, 45 Genetic Structures ... ... , 45 Cells and Biological Structures, 45 Composite Detectors and Arrays, 45 Linear Detector Arrays, 45 ... ... Reducing Tobacco Smoking, 235 Modifying Alcohol Consumption, 236 HPV Vaccination, 236 Ultraviolet Light ... ... Sharma -- Introduction, 579 -- Physics and Technology of Proton Beam Therapy, 579 Physical Characteristics ...
Eighth edition xxiii, 615 stran : ilustrace, tabulky ; 28 cm
- MeSH
- nádory radioterapie MeSH
- nukleární lékařství metody MeSH
- radioterapie metody MeSH
- Publikační typ
- učebnice MeSH
- Konspekt
- Učební osnovy. Vyučovací předměty. Učebnice
- Lékařské vědy. Lékařství
- NLK Obory
- radiologie, nukleární medicína a zobrazovací metody
- onkologie
- NLK Publikační typ
- kolektivní monografie