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4712. Experiment NOvA poprvé zaznamenal dráhy prolétajících částic
- Creator:
- Soustružník, Karel, Jediný, Filip, Leitner, Rupert, and Lokajíček, Miloš
- Format:
- Type:
- model:article and TEXT
- Subject:
- fyzika, physics, 6, and 53
- Language:
- Czech
- Description:
- Vědci z experimentu NOvA koncem března tohoto roku úspěšně otestovli první plně funkční části tzv. vzdáleného detektoru. Po jejím zapnutí poprvé zaznamenali dráhy částic kosmického záření prolétajících aktivní částí detektoru. V polovině letošního roku bude spuštěn neutrinový svazek a detektory experimentu.NOvA začnou pátrat po interakcích neutrin s cílem určit jejich některé vlastnosti., Karel Soustružník [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4713. Experimental endotoxemia induces leukocyte adherence and plasma extravasation within the rat pial microcirculation
- Creator:
- Zhou, J., Schmidt, M., Johnston, B., Wilfart, F., Whynot, S., Hung, O., Murphy, M., Černý, V., Pavlovic, D., and Lehmann, C.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, sepse, hematoencefalická bariéra, sepsis, blood-brain barrier, endotoxin, intravital microscopy, 14, and 612
- Language:
- English
- Description:
- Disturbance of capillary perfusions due to leukocyte adhesion, disseminated intravascular coagulat ion, tissue edema is critical components in the pathophysiology of sepsis. Alterations in brain microcirculation during sepsis are not clearly understood. The aim of this study is to gain an improved understanding of alterations through direct visualization of brain microcirculations in an experimental endotoxemi a using intravital microscopy (IVM). Endotoxemia was induced in Lewis rats with Lipopolysaccharide (LPS, 15 mg/kg i.v.). The dura mater was removed via a cranial window to expose the pial vessels on the brain surface. Using fluorescence dyes, plasma extravasation of pial venous vessels and leukocyte-endothelial interaction were visualized by intravital microscopy 4 h after LPS administration. Plasma cytokine levels of IL1-β, IL-6, IFN-γ, TNF-α and KC/GRO were evaluated after IVM. A sign ificant plasma extravasation of the pial venous vessels was found in endotoxemia rats compared to control animals. In addition , a significantly increased number of leukocytes adherent to the pial venous endothelium was observed in septic animals. Endotoxemia also induced a significant elevation of plasma cytokine levels of IL1-β, IL-6, IFN-γ, TNF-α and KC/GRO. Endotoxemia increased permeability in the brain pial vessels accompanied by an increase of leukocyte-endothelium interactions and an increase of inflammatory cytokines in the plasma., J. Zhou ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4714. Experimental evaluation of the cardiac rhythm originating in myocardial sleeves of pulmonary veins using a monophasic action potential
- Creator:
- Otomar Kittnar, Yang, S.-G., and Mikuláš Mlček
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fibrilace síní, atrial fibrillation, myocardial sleeves, pulmonary veins, monophasic action potential, 14, and 612
- Language:
- English
- Description:
- Spontaneous depolarization similar to that from the sinus node was documented from the myocardial sleeves of pulmonary veins (PV) after isolation procedures. It was then hypothesized that sinus node-like tissue is present in the PVs of humans. Based on a number of features, the myocar dium of myocardial sleeves (MS) is highly arrhythmogenic. Membrane potentials originating from MS are invariably recordable at the PVs ostia in patients with atrial fibrillation (AF) and delayed conduction around the PVs ostia may play a role in re-e ntry process responsible for the initiation and maintenance of AF. Diagnostic and therapeutic evidence of premature atrial beats induced in MS of PVs and resulting in launch of AF was detected by 3D electroanatomic method of monophasic action potential (MAP). MAP recording plays an important role in a di rect view of human myocardial electrophysiology under both physiological and pathological conditions. Its crucial importance lies in the fact that it enables the study of the action potential of myocardial cell in vivo and, therefore, the study of the dynamic relation of this potential with all the organism variables. The knowledge of pathological MAPs from PV myocardial sleeves can help us to confirm a diagnosis when finding the similar action potential morphology. MAP can be also used to evaluate the therap eutic efficiency of vagal nerves suppression, radiofrequency ablation or other treatment procedures in PVs myocardial sleeves as well as for post- treatment following up., O. Kittnar, S.-G. Yang, M. Mlček., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4715. Experimental methods for simultaneous measurement of action potentials and electrograms in isolated heart
- Creator:
- Jana Kolářová, Kateřina Fialová, Oto Janoušek, Marie Nováková, and Ivo Provazník
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, isolated heart, action potential, electrogram, voltage sensitive dye, ratiometry, 14, and 612
- Language:
- English
- Description:
- Monophasic action potential (MAP) can be recorded from the heart surface by optical method based on fluorescence measurement. The motion of isolated heart during experiment caused additional noise in recorded signal. The motion artifact can be eliminated by ratiometric fluorescence emission measurements. This study is based on experiments in which optical MAP measurement is done by single-wavelength and dualwavelength measurement of fluorescence emission. Both recording setups are presented and their advantages and disadvantages are discussed. MAPs recorded by both methods from isolated rabbit hearts perfused according to Langendorff are presented. Simultaneous electrograms (EG) and MAPs recording are analyzed and measurement of velocity of impulse conduction through heart tissue is presented., J. Kolářová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4716. Experimental microsporidiosis in immunocompetent immunodeficient mice and monkeys
- Creator:
- Didier, E.S., Varner, P.W., Didier, P.J., Aldras, A.M., Millichamp, N.J., Murphey-Corb, M., Bohm, R., and Shadduck, J.A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Microsporidia, AIDS, opportunistic infection, Nosema, Encephalitozoon, encephaiitozoonosis, and microsporidiosis
- Language:
- English
- Description:
- Microsporidia cause opportunistic infections in AIDS patients and commonly infect laboratory animals, as well. Euthymie C57B1/6 mice experimentally infected with intraperitoneal injections of lxlO6 Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923, Encephalitozoon hellem Didier et al., 1991, or Nosema comeum Shadduck et al., 1990 displayed no clinical signs of disease. Athymic mice, however, developed ascites and died 8-16 days after inoculation with N. comeum, 21-25 days after inoculation with E. cuniculi, and 34-37 days after inoculation with E. hellem. All athymic mice displayed hepatomegaly, dilated intestine and accumulation of ascites fluid. Granulomatous lesions were primarily located in the liver, lung, pancreas, spleen, and on serosal surfaces of abdominal organs.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4717. Experimental models of acute lung injury in the newborns
- Creator:
- Daniela Mokrá and Andrea Čalkovská
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, novorozenci, newborns, acute lung injury, animal model, surfactant depletion, meconium aspiration, 14, and 612
- Language:
- English
- Description:
- Acute lung injury in the preterm newborns can originate from prematurity of the lung and insufficient synthesis of pulmonary surfactant. This situation is known as respiratory distress syndrome (RDS). In the term neonates, the respiratory insufficiency is related to a secondary inactivation of the pulmonary surfactant, for instance, by action of endotoxins in bacterial pneumonia or by effects of aspirated meconium. The use of experimental models of the mentioned situations provides new information on the pathophy siology of these disorders and offers unique possibility to test novel therapeutic approaches in the conditions which are very similar to the clinical syndromes. Herewith we review the advantages and limitations of the use of experimental models of RDS and meconium aspiration syndrome (MAS) and their value for clinics., D. Mokra, A. Calkovska., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4718. Experimental Models of Cardiovascular Overload: April 11-12, 2000
- Format:
- print, bez média, and svazek
- Type:
- article, sborníky abstraktů, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, konference, physiology, conferences, 14, and 612
- Language:
- English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4719. Experimental models of hyperlipoproteinemia and atherosclerosis
- Creator:
- Rudolf Poledne and Jurčíková-Novotná, L.
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, lipoproteiny, ateroskleróza, lipoproteins, atherosclerosis, atherosclerosis-models, 14, and 612
- Language:
- English
- Description:
- The first experimental model of atherosclerosis (in rabbits) is more than hundred years old. Several animal species have bee n used to produce hyperlipoproteine mia and possible atherosclerosis. The gene manipulation produced the most used models recently. This review acknowledges the extensive study of atherosclerotic changes in experimental models of hyperlipoprotein emia and at herosclerosis to come to light thus far and the purpose here is not only to summariz e the published data but also to try to add some details of our experience in using these models. In addition to rabbit (the old but also improved model by reno-vascular hy pertension) dog, birds, pig, hamster, mice, rat and non-human primate’s animal models are described. The gene manipulation produced the most used models two decades ago. Germline genetically engineered (without apoE or LDL receptor genes) animals have beco me the most used models producing atherosclerotic changes in the aorta. Recent new models also producing atherosclerotic changes but without germline genetic manipulation are also described., R. Poledne, L. Jurčíková-Novotná., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4720. Experimental models of spontaneous ventricular arrhythmias and of sudden cardiac death
- Creator:
- Milan Štengl
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, srdce, náhlá srdeční smrt, heart, sudden cardiac death, experimental animal model, 14, and 612
- Language:
- English
- Description:
- Sudden cardiac death defined as natural death from cardiac causes occurring within one hour of the onset of acute symptoms is one of the most significant non-injury causes of death in the adult population of industrialised countries. The understanding of the mechanisms leading to sudden cardiac death is so far limited. Recently, a number of experimental animal models with high incidence of sudden cardiac death were developed and are intensively studied to get new insights into the sudden cardiac death mechanisms. In this review the animal models of sudden cardiac death are summarized and their principal properties shortly described., M. Štengl., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public