Gastrointestinální trakt (GIT) byl dlouho u kriticky nemocných považován za nevýznamný, metabolicky a imunologicky neaktivní orgán. Ve skutečnosti však intestinální trakt vykonává celou řadu důležitých funkcí, které ve svém důsledku významně ovlivňují morbiditu a mortalitu mnoha kriticky nemocných. Jeho rozsáhlá absorpční plocha umožňuje vstřebávání nutrientů a současně představuje významnou bariéru před proniknutím intraluminálních mikrobů či toxických produktů do organizmu. Kromě toho je GIT největším lymfoidním orgánem v těle, významně se uplatňujícím při imunitní odpovědi kriticky nemocných. Dysfunkce GIT vzniká u nemocných na jednotkách intenzívní péče velmi často a časně. Abnormální kolonizace, narušená střevní epiteliální bariérová funkce a translokace bakterií představují hlavní komponenty dysfunkce GIT, které se uplatňují v patogenezi sepse a multiorgánového selhání. Tento článek shrnuje současný názor na úlohu GIT u kriticky nemocných se zaměřením na 1) hypotézu centrální úlohy GIT u sepse, traumatu a vývoje multiorgánové dysfunkce, 2) patofyziologii dysfunkce GIT, 3) monitoraci funkce GIT a 4) protektivní opatření a nové léčebné perspektivy.
Until relatively recently, the gastrointestinal (GI) trakt was considered a dormant, metabolically and immunologically inactive orgán in critically illnesses. However, the GI trakt provides a number of crucial functions that, in fact, may influence morbidity and mortality of many critically ill patients. Its large absorptive area provides a site for nutrient digestion and utilization and serves as an important barrier preventing the systemic absorption of intraluminal microbes and its toxic products. Moreover, the GI trakt is the largest reservou of lymphocytes in the body, which significantly contribute to the immune response of the critically ill patients. The gut dysfunction occurs frequently and early in the intensive care patients. Abnormal colonization, impaired intestinal epithelial barrier function and bacterial translocation represent the key components of gut failure implicating in the pathogenesis of sepsis and multiorgan dysfunction. This review summarizes recent insights finto the role of the gut in critically ill patients with particular focus on 1) the basis of „gut-origin hypothesis", 2) pathophysiology of gut dysfunction, 3) monitoring of intestinal function, and 4) protective measures and novel therapeutic strategies.
- MeSH
- Research Support as Topic MeSH
- Gastrointestinal Tract microbiology physiopathology MeSH
- Capillary Permeability MeSH
- Humans MeSH
- Multiple Organ Failure physiopathology therapy MeSH
- Critical Care MeSH
- Regional Blood Flow MeSH
- Intestinal Mucosa physiopathology MeSH
- Systemic Inflammatory Response Syndrome MeSH
- Check Tag
- Humans MeSH
- Publication type
- Review MeSH
Scarcity of medical resources inspired many teams worldwide to design ventilators utilizing different approaches during the recent COVID-19 pandemic. Although it can be relatively easy to design a simple ventilator in a laboratory, a large scale production of reliable emergency ventilators which meet international standards for critical care ventilators is challenging and time consuming. The aim of this study is to propose a novel and easily manufacturable principle of gas mixing and inspiratory flow generation for mechanical lung ventilators. Two fast ON/OFF valves, one for air and one for oxygen, are used to control the inspiratory flow generation using pulse width modulation. Short gas flow pulses are smoothed by low-pass acoustic filters and do not propagate further into the patient circuit. At the same time, the appropriate pulse width modulation of both ON/OFF valves controls the oxygen fraction in the generated gas mixture. Tests focused on the accuracy of the delivered oxygen fractions and tidal volumes have proved compliance with the international standards for critical care ventilators. The concept of a simple construction using two fast ON/OFF valves may be used for designing mechanical lung ventilators and thus suitable for their rapid production during pandemics.
- MeSH
- COVID-19 * therapy MeSH
- Mass Casualty Incidents * MeSH
- Oxygen MeSH
- Humans MeSH
- Ventilators, Mechanical MeSH
- Pandemics MeSH
- Critical Care MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Fluorochrome selection is a key step in designing multi-color antibody panels. The list of available fluorochromes is continuously growing, fitting current needs in clinical flow cytometry to simultaneously use more markers to better define multiple leukocyte subpopulations in a single tube. Several criteria guide fluorochrome selection: i) the fluorescence profiles (excitation and emission), ii) relative brightness, iii) fluorescence overlap, iv) fluorochrome stability, and v) reproducible conjugation to antibodies. Here we used 75 samples (45 bone marrow and 30 blood) to illustrate EuroFlow strategies for evaluation of compatible fluorochromes, and how the results obtained guide fluorochrome selection as a critical step in the antibody-panel building process. Our results allowed identification of optimal fluorescence profiles (e.g. higher fluorescence intensity and/or resolution with limited fluorescence overlap into neighbor channels) for brilliant violet (BV)421 and BV510 in the violet laser and allophycocyanin (APC) hilite 7 (H7) or APC C750 in the red laser vs. other candidate fluorochromes generally applied for the same detectors and here evaluated. Moreover, evaluation of the same characteristics for another group of fluorochromes (e.g. BV605, BV650, PE CF594, AF700 or APC AF700) guided selection of the most appropriate fluorochrome conjugates to be combined in a multi-color antibody panel. Albeit this is a demanding approach, it could be successfully applied for selection of fluorochrome combinations for the EuroFlow antibody panels for diagnosis, classification and monitoring of hematological malignancies and primary immunodeficiencies. Consequently, sets of 8-, 10- and 12-color fluorochrome combinations are proposed as frame of reference for initial antibody panel design.
- MeSH
- Fluorescent Dyes * MeSH
- Immunophenotyping methods MeSH
- Humans MeSH
- Flow Cytometry methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Analysis and sorting of plant chromosomes (plant flow cytogenetics) is a special application of flow cytometry in plant genomics and its success depends critically on sample quality. This unit describes the methodology in a stepwise manner, starting with the induction of cell cycle synchrony and accumulation of dividing cells in mitotic metaphase, and continues with the preparation of suspensions of intact mitotic chromosomes, flow analysis and sorting of chromosomes, and finally processing of the sorted chromosomes. Each step of the protocol is described in detail as some procedures have not been used widely. Supporting histograms are presented as well as hints on dealing with plant material; the utility of sorted chromosomes for plant genomics is also discussed. © 2016 by John Wiley & Sons, Inc.
- MeSH
- Chromosomes, Plant metabolism MeSH
- DNA, Plant genetics MeSH
- In Situ Hybridization, Fluorescence MeSH
- Karyotyping MeSH
- Meristem cytology drug effects MeSH
- Metaphase drug effects MeSH
- Molecular Weight MeSH
- Nitrous Oxide pharmacology MeSH
- Proteomics MeSH
- Flow Cytometry methods MeSH
- Plants genetics MeSH
- Seeds drug effects MeSH
- Publication type
- Journal Article MeSH
Endoteliální glykokalyx představuje klíčovou komponentu endoteliální bariéry na její intraluminální straně a má rozhodující úlohu při udržování vaskulární integrity za fyziologických a velmi pravděpodobně i patologických stavů. Biochemická struktura glykokalyx determinuje její vysokou vulnerabilitu, v kontextu kritických stavů je rozvoj endoteliální dysfunkce vždy spojen s určitým stupněm poškození glykokalyx. Současný stav poznání umožňuje formulovat předpoklad vztahu mezi funkcí glykokalyx a náhradou objemu v rámci tekutinové terapie. Minimalizace poškození (případně reparace již poškozené) glykokalyx představuje racionální klinický koncept k udržení/obnovení endoteliální integrity a dosažení maximální možné objemové efektivity tekutinové náhrady. Článek přináší shrnutí dané problematiky a diskutuje argumenty pro zohlednění významu glykokalyx při rozhodování o způsobu vedení tekutinové léčby.
The endothelial glycocalyx represents a key component of the endothelial barrier on its intraluminal side. It is vital for the maintenance of vascular integrity in physiological conditions and most probably also in pathophysiological conditions. Due to its sugar-based structure, it is highly vulnerable and in the context of critical conditions of patients, the development of endothelial dysfunction is always linked to a certain degree of damage of the glycocalyx. The current state of knowledge favours determining a presumption of a relationship between the function of the glycocalyx and volume replacement therapy. Attempts to minimize damage (and to allow spontaneous recovery) are the only available rational concepts of maintaining integrity of the endothelium and reaching the maximal effect of infusion therapy. This narrative review article brings a summary of this topic and discusses arguments for consideration of the significance of the glycocalyx in the decision-making in fluid therapy.
- Keywords
- endoteliální glykokalyx,
- MeSH
- Endothelium, Vascular metabolism MeSH
- Glycocalyx * physiology metabolism drug effects MeSH
- Capillary Permeability MeSH
- Humans MeSH
- Microcirculation physiology MeSH
- Critical Care MeSH
- Fluid Therapy * adverse effects MeSH
- Check Tag
- Humans MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
