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362. Prompt rise in urinary ammonium excretion suffices to mitigate metabolic acidosis in an experimental animal model of severe normovolemic hemodilution
- Creator:
- Teloh, J. K., Waack, I. N., and Groot, H. de
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, acidóza, moč, močové cesty, acidosis, urine, urinary tract, renal acid excretion, normovolemic hemodilution, acute metabolic acidosis, ammonium excretion, acid-base homeostasis, 14, and 612
- Language:
- English
- Description:
- Recently, we have established a model of severe stepwise normovolemic hemodilution to a hematocrit of 10 % in rats employing three different colloidal volume replacement solutions (Voluven, Volulyte and Gelafundin) that are routinely used in clinical practice at present. We did not see severe dilutional acidosis as to be expected, but a decline in urinary pH. We here looked on further mechanisms of renal acid excretion during normovolemic hemodilution. Bicarbonate, which had been removed during normovolemic hemodilution, was calculated with the help of the Henderson-Hasselbalch equation. The urinary amount of ammonium as well as phosphate was determined in residual probes. The absolute amount of free protons in urine was obtained from the pH of the respective samples. The amount of protons generated during normovolemic hemodilution was approximately 0.6 mmol. During experimental time (5.5 h), distinct urinary ammonium excretion occurred (Voluven 0.52 mmol, Volulyte 0.39 mmol and Gelafundin 0.77 mmol). Proton excretion via the phosphate buffer constituted 0.04 mmol in every experimental group. Excretion of free protons was in the range of 10-6 mmol. The present data prove that the prompt rise in urinary ammonium excretion is also valid for acute metabolic acidosis originating from severe normovolemic hemodilution., J. K. Teloh, I. N. Waack, H. de Groot., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
363. Protection of cardiac cell-to-cell coupling attenuate myocardial remodeling and proarrhythmia induced by hypertension
- Creator:
- Egan Benova, T., Szeiffova Bacova, B., Viczenczova, C., Diez, E., Miroslav Barančík, and Narcisa Tribulová
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hypertenze, hypertension, arrhythmias, connexin-43, cardioprotection, 14, and 612
- Language:
- English
- Description:
- Gap junction connexin channels are important determinants of myocardial conduction and synchronization that is crucial for coordinated heart function. One of the main risk factors for cardiovascular events that results in heart attack, congestive heart failure, stroke as well as sudden arrhythmic death is hypertension. Mislocalization and/or dysfunction of specific connexin-43 channels due to hypertension-induced myocardial remodeling have been implicated in the occurrence of lifethreatening arrhythmias and heart failure in both, humans as well as experimental animals. Recent studies suggest that downregulation of myocardial connexin-43, its abnormal distribution and/or phosphorylation might be implicated in this process. On the other hand, treatment of hypertensive animals with cardioprotective drugs (e.g. statins) or supplementation with non-pharmacological compounds, such as melatonin, omega-3 fatty acids and red palm oil protects from lethal arrhythmias. The antiarrhythmic effects are attributed to the attenuation of myocardial connexin-43 abnormalities associated with preservation of myocardial architecture and improvement of cardiac conduction. Findings uncover novel mechanisms of cardioprotective (antihypertensive and antiarrhythmic) effects of compounds that are used in clinical settings. Well-designed trials are needed to explore the antiarrhythmic potential of these compounds in patients suffering from hypertension., T. Egan Benova, B. Szeiffova Bacova, C. Viczenczova, E. Diez, M. Barancik, N. Tribulova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
364. Protein interactions with quaternized chitosan / heprain multilayers
- Creator:
- Kumorek, M., Dana Kubies, and Riedel, T.
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, chitosan, bílkoviny, proteins, heparin, basic fibroblasts growth factor, layer-by-layer, 14, and 612
- Language:
- English
- Description:
- Understanding the behavior of single proteins at the polyelectrolyte multilayer film/solution interface is of prime importance for the designing of bio-functionalized surface coatings. In the present paper, we study the adsorption of the model proteins, albumin and lysozyme, as well as basic fibroblast growth factor (FGF-2) on a polysaccharide multilayer film composed of quaternized chitosan and heparin. Several analytical methods were used to describe the formation of the polysaccharide film and its interactions with the proteins. Both albumin and lysozyme adsorbed on quaternized chitosan/heparin films, however this process strongly depended on the terminating polysaccharide. Protein adsorption was driven mainly by electrostatic interactions between protein and the terminal layer of the film. The effective binding of FGF-2 by the heparinterminated film suggested that other interactions could also contribute to the adsorption process. We believe that this FGF-2- presenting polysaccharide film may serve as a biofunctional surface coating for biologically-related applications., M. Kumorek, D. Kubies, T. Riedel., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
365. Proteomic analysis of peroxynitrite-induced protein nitration in isolated beef heart mitochondria
- Creator:
- Matej Kohutiar, Adam Eckhardt, Jiří Wilhelm, Šantorová, P, and Ivan Mikšík
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- Type:
- model:article and TEXT
- Subject:
- fyziologie člověka, human physiology, Mitochondrial proteome, Peroxynitrite, 3-nitrotyrosine, 2D electrophoresis, Mass spectrometry, 14, and 612
- Language:
- English
- Description:
- Summary Mitochondria are exposed to reactive nitrogen species under physiological conditions and even more under several pathologic states. In order to reveal the mechanism of these processes we studied the effects of peroxynitrite on isolated beef heart mitochondria in vitro. Peroxynitrite has the potential to nitrate protein tyrosine moieties, break the peptide bond, and eventually release the membrane proteins into the solution. All these effects were found in our experiments. Mitochondrial proteins were resolved by 2D electrophoresis and the protein nitration was detected by immunochemical methods and by nano LC-MS/MS. Mass spectrometry confirmed nitration of ATP synthase subunit beta, pyruvate dehydrogenase E1 component subunit beta, citrate synthase and acetyl-CoA acetyltransferase. Immunoblot detection using chemiluminiscence showed possible nitration of other proteins such as cytochrome b-c1 complex subunit 1, NADH dehydrogenase [ubiquinone] ironsulfur protein 2, elongation factor Tu, NADH dehydrogenase [ubiquinone] flavoprotein 2, heat shock protein beta-1 and NADH dehydrogenase [ubiquinone] iron-sulfur protein 8. ATP synthase beta subunit was nitrated both in membrane and in fraction prepared by osmotic lysis. The high sensitivity of proteins to nitration by peroxynitrite is of potential biological importance, as these enzymes are involved in various pathways associated with energy production in the heart., M. Kohutiar, A. Eckhardt, I. Mikšík, P. Šantorová, J. Wilhelm., and Seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
366. Proteomic approach for identification of IgA nephropathy-related biomarkers in urine
- Creator:
- Prikryl, P., Vojtova, L., Dita Maixnerová, Martin Vokurka, Neprasova, M., Tomáš Zima, and Tesar, V.
- Format:
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- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, nemoci ledvin, kidney diseases, urine proteomics, IgAN, LC-MS/MS, 14, and 612
- Language:
- English
- Description:
- Proteinuria is often used as a surrogate marker in monitoring and predicting outcome in patients with chronic kidney diseases, but it is non-specific. IgAN belongs to the most common primary glomerulonephritis worldwide with serious prognosis. The main aim of this work was to assess differences in urine proteins in patients with IgA nephropathy and to identify abnormal proteins as potential biomarkers of IgA nephropathy or the renal disease. In our pilot project, we selected 20 patients and compared them with 20 healthy volunteers. Protein quantification was performed using iTRAQ (isobaric tag for relative and absolute quantitation) labeling method. The peptides were separated by the isoelectric focusing method (IEF) and nano-LC with C18 column and identified by mass spectrometry using MALDI-TOF/TOF MS. Proteins´ lists obtained from IEF-LC-MS-MS/MS analysis were combined and contained 201 proteins. It was found out that 113 proteins were common in both experiments. 30 urinary proteins were significantly up- or down-regulated in patients with IgA nephropathy. We characterized potential biomarkers such as alpha-1-antitrypsin, apolipoprotein A-I, CD44 antigen or kininogen. Potential biomarkers of IgAN should be validated in further studies., P. Prikryl, L. Vojtova, D. Maixnerova, M. Vokurka, M. Neprasova, T. Zima, V. Tesar., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
367. Pulmonary surfactant and bacterial lipopolysaccharide: the interaction and its functional consequences
- Creator:
- Kolomaznik, M., Nova, Z., and Andrea Čalkovská
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- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, plíce, lungs, lipopolysaccharide, pulmonary surfactant, inhibition, alveolar type II cells, lung injury, 14, and 612
- Language:
- English
- Description:
- The respiratory system is constantly exposed to pathogens which enter the lungs by inhalation or via blood stream. Lipopolysaccharide (LPS), also named endotoxin, can reach the airspaces as the major component of the outer membrane of Gram-negative bacteria, and lead to local inflammation and systemic toxicity. LPS affects alveolar type II (ATII) cells an d pulmonary surfactant and although surfactant molecule has the effective protective mechanisms, excessive amount of LPS interacts with surfactant film and leads to its inactivation. From immunological point of view, surfactant specific proteins (SPs) SP-A and SP-D are best characterized, however, there is increasing evidence on the involvement of SP-B and SP-C and certain phospholipids in immune reactions. In animal models, the instillation of LPS to the respiratory system induces acute lung injury (ALI). It is of clinical importance that endotoxin-induced lung injury can be favorably influenced by intratracheal instillation of exogenous surfactant. The beneficial effect of this treatment was confirmed for both natural porcine and synthetic surfactants. It is believed that the surfactant preparations have anti-inflammatory properties through regulating cytokine production by inflammatory cells. The mechanism by which LPS interferes with ATII cells and surfactant layer, and its consequences are discussed below., M. Kolomaznik, Z. Nova, A. Calkovska., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
368. Pupillary light reflex is altered in adolescent depression
- Creator:
- Mestanikova, A., Igor Ondrejka, Mestanik, M., Cesnekova, D., Visnovcova, Z., Bujnakova, I., Oppa, M., Andrea Čalkovská, and Ingrid Tonhajzerová
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- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, autonomní nervový systém, autonomic nervous system, major depressive disorder, pupillary light reflex, adolescent patients, autonomic lateralization, 14, and 612
- Language:
- English
- Description:
- Major depressive disorder is associated with abnormal autonomic regulation which could be noninvasively studied using pupillometry. However, the studies in adolescent patients are rare. Therefore, we aimed to study the pupillary light reflex (PLR), which could provide novel important information about dynamic balance between sympathetic and parasympathetic nervous system in adolescent patients suffering from major depression. We have examined 25 depressive adolescent girls (age 15.2±0.3 y ear) prior to pharmacotherapy and 25 age/gender-matched healthy subjects. PLR parameters were measured separately for both eyes after 5 min of rest using Pupillometer PLR-2000 (NeurOptics, USA). The constriction percentual change for the left eye was significantly lower in depressive group compared to control group (-24.12±0.87 % vs. - 28.04±0.96%, p˂0.01). Furthermore, average constriction velocity and maximum constriction velocity for the left eye were significantly lower in depressive group compared to control group (p˂0.05, p˂0.01, respectively). In contrast, no significant between-groups differences were found for the right eye. Concluding, this study revealed altered PLR for left eye indicating a deficient parasympathetic activity already in adolescent major depression. Additionally, the differences between left and right eye could be related to functional lateralization of autonomic control in the central nervous system., A. Mestanikova, I. Ondrejka, M. Mestanik, D. Cesnekova, Z. Visnovcova, I. Bujnakova, M. Oppa, A. Calkovska, I. Tonhajzerova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
369. Quercetin protects against stress-induced anxiety- and depression-like behavior and improves memory in male mice
- Creator:
- Samad, N, Saleem, A, Yasmin, F, and Shehzad, M. A
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- Type:
- model:article and TEXT
- Subject:
- acetylcholin, acetylcholine, quercetin, immobilization stress, antioxidant enzymes, serotonin, 14, and 612
- Language:
- English
- Description:
- The present study evaluates the protective role of Quercetin (Quer), against immobilization stress- induced anxiety, depression and cognition alteration in mice using behavioral and biochemical parameters. 24 adult Albino mice were distributed into 2 groups vehicle (n=12; 1 ml/kg) and Quer injected (n=12; 20 mg/kg/ml). The animals received their respective treatment for 14 days. On day 15, after the drug administration, animals were sub-divided into 4 groups (n=6); (i) unstressed + vehicle; (ii) stressed + vehicle; (iii) unstressed + Quer; (iv) stressed + Quer. On day 16, 24 h after the immobilization stress behavioral activities (light-dark activity, elevated plus maze, Morris water maze, and forced swim test) monitored and then animals were decapitated 1 h after the drug administration. Brain samples were collected for biochemical (antioxidant enzymes, AChE, ACh, 5-HT and its metabolite) analysis. The present study indicates the Quer reversed the stress-induced anxiety and depression, in addition, memory performance was more enhanced in stressed group. Following the treatment of Quer, stress-induced elevation of lipid peroxidation and suppression of antioxidant enzymes were also reversed. Administration of Quer decreased AChE in unstressed, while levels of acetylcholine were increased in vehicle and Quer treated stressed animals. The metabolism of 5-HT was increased in Quer treated stressed than unstressed animals. In conclusion, the present finding showed that Quer could prevent the impairment of antioxidant enzymes and also regulate the serotonergic and cholinergic neurotransmission and produce antianxiety, antidepressant effect and enhance memory following 2 h immobilization stress in mice., N. Samad, A. Saleem, F. Yasmin, M. A. Shehzad., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
370. Radiofrequency electromagnetic field affects heart rate variability in rabbits
- Creator:
- Míšek, Jakub, Veterník, Marcel, Tonhajzerová, Ingrid, Jakušová, Viera, Janousek, Ladislav, and Jakuš, Ján
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- mobilní komunikace, králíci, fyziologie, mobile communication, rabbits, physiology, cardiac autonomic regulation, cell phone, radiofrequency electromagnetic exposure, 14, and 612
- Language:
- English
- Description:
- The aim of this study was to assess the effects of radiofrequency electromagnetic field (RF EMF) on heart rate variability (HRV) in rabbits with intensity slightly exceeding the limits for occupations. Totally 21 New Zealand white rabbits divided into two groups were used in this double-blind study. The first group of animals without general anesthesia was subjected to HRV examination under exposure to a device generated RF EMF source (frequency 1788 MHz, intensity 160 V/m, lasting 150 min.). The second group (premedications + α chloralose mg/kg) underwent the same protocol under the exposure to the real RF EMF signal from the base stations of mobile providers (frequency range 1805 - 1870 MHz - corresponding to the downlink signal of Slovak mobile providers, 160 V/m, 150 min., respectively). Individual 5-min records were used to analyze the HRV parameters: heart rate and root Mean Square of the Successive Differences (rMSSD) for time domain analysis and spectral powers in the low (LF-VFS) and high frequency (HF-VFS) bands for frequency domain analysis. Our study revealed the increased in HRV parameters (HF-HRV, rMSSD) associated with lower heart rate indicating increased cardiac vagal control under the exposure to RF EMF in experimental methods., Jakub Misek, Marcel Veterník, Ingrid Tonhajzerova, Viera Jakusova, Ladislav Janousek, Jan Jakus., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public