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2122. Barevný svět zkamenělin
- Creator:
- Budil, Ivo and Mikuláš , Radek
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2123. Bariéry nervového systému za fyziologických a patologických stavů
- Creator:
- Piťha, Jiří
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, přehledy, and TEXT
- Subject:
- centrální nervový systém, periferní nervový systém, hematoencefalická bariéra--fyziologie--patologie, permeabilita buněčné membrány, biologický transport, homeostáza, endoteliální buňky--fyziologie--patologie, akvaporin 4--fyziologie, roztroušená skleróza--patologie, neuromyelitis optica, epilepsie, Alzheimerova nemoc, cévy--metabolismus, mozek--krevní zásobení, kapilární permeabilita--fyziologie, endotel cévní--fyziologie, and lidé
- Language:
- Czech and English
- Description:
- Centrální a periferní nervový systém jsou odděleny od krevního řečiště bariérami, které brání volnému přechodu ve vodě rozpustných molekul prostřednictvím těsných spojů, jež propojují endoteliální buňky a epiteliální buňky plexus chorioideus. Tyto bariéry též hrají roli v influxu esenciálních molekul a odstraňování xenobiotik. V posledních letech jsou objasňovány rozdíly a společné rysy jednotlivých bariérových systémů. Jejich poruchy hrají klíčovou roli v celé řadě chorob nervového systému. Článek objasňuje strukturu a funkci bariérových systémů za fyziologických a patologických okolností., Central and peripheral nervous systems are separated from the bloodstream by barrier structures that prevent free migration of water-soluble molecules through the tight junctions of the choroid plexus endothelial and epithelial cells. These barriers also play a role in the influx of essential molecules and elimination of xenobiotics. In recent years, differences and common features of the various barrier systems are being explored. Their disorders play a key role in a number of nervous system diseases. The present paper describes the structure and function of barrier systems under physiological and pathological conditions., and J. Piťha
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2124. Barokní nástěnná malba v monastické kultuře
- Creator:
- Martin Mádl
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Věda. Všeobecnosti. Základy vědy a kultury. Vědecká práce, barokní nástěnná malba, výzkumné projekty, baroque mural painting, research projects, Evropa střední, Europe, Central, 12, and 00
- Language:
- Czech
- Description:
- Martin Mádl.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2125. Baroque Organ Cases with Angelic Musicians: Johann Frančišek Janeček and the Embellishment of his Organs
- Creator:
- Koter, Darja
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Description:
- The paper discusses five instruments made by the organ-builder Johann Frančišek Janeček, who originated from a Bohemian or Moravian family, and who worked in Celje in Slovenia in the 18th century. Five of his preserved organs are embellished with angelic musicians: King David with the harp or St. Cecilia with the organ. The organ cases and figures with musical instruments bear certain resemblances to the work of the Bohemian and Moravian organ-builders. The paper also mentions some characteristics of the organ preserved in the church of Saint Catherine in Prague, made by Martin Janeãek and Jan Storck between 1734 and 1741.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2126. Baroreflex control of heart rate in young and adult salt hypertensive inbred dahl rats
- Creator:
- Jan Nedvídek and Josef Zicha
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, srdeční rytmus, krevní tlak, stárnutí, heart rate, blood pressure, aging, baroreflex sensitivity, salt intake, phenylephrine, inbred Dahl rats, 14, and 612
- Language:
- English
- Description:
- Baroreflex control of heart rate was studied in inbred salt-sensitive (SS/Jr) and salt-resistant (SR/Jr) Dahl rats that were subjected to chronic dietary sodium chloride loading (for 4 weeks) either in youth or only in adulthood, i.e. from the age of 4 or 12 weeks. Using phenylephrine administration to pentobarbital-anesthetized male rats we have demonstrated the decreased baroreflex sensitivity (lower slope for reflex bradycardia) in young prehypertensive SS/Jr rats fed a low-salt diet as compared to age-matched SR/Jr animals. High salt intake further suppressed baroreflex sensitivity in young SS/Jr but not in SR/Jr rats. Baroreflex sensitivity decreased with age in SR/Jr rats, whereas it increased in SS/Jr rats fed a low-salt diet. Thus at the age of 16 weeks baroreflex sensitivity was much higher in SS/Jr than in SR/Jr animals. High salt intake lowered baroreflex sensitivity even in adult SS/Jr rats without affecting it in adult SR/Jr rats. Nevertheless, baroreflex sensitivity was significantly lower in young SS/Jr rats with a severe salt hypertension than in adult ones with a moderate blood pressure elevation. It is concluded that the alterations of baroreflex sensitivity in young inbred SS/Jr rats (including the response to high salt intake) are similar to those described earlier for outbred salt-sensitive Dahl rats. We have, however, disclosed contrasting age-dependent changes of baroreflex sensitivity in both inbred substrains of Dahl rats., J. Nedvídek, J. Zicha., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2127. Baroreflex sensitivity and essential hypertension in adolescents
- Creator:
- Nataša Honzíková and Bohumil Fišer
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, adolescenti, obezita, genetika, human physiology, adolescents, obesity, genetics, esenciální hypertenze, baroreflexní citlivost, essential hypertension, baroreflex sensitivity, 14, and 612
- Language:
- English
- Description:
- 1a_It has been known for many years that baroreflex sensitivity is lowered in hypertensive patients. There are several known factors implicating this association, e.g. high blood pressure leads to remodeling of the carotid arterial wall, to its stiffness and to a diminished activation of baroreceptors; leptin released from a fatty tissue activates the sympathetic nervous system etc. On the other hand, low baroreflex sensitivity (BRS, usually quantified in ms/mmHg) can be inborn. Studies on primary hypertension in children and adolescents have brought new information about the role of baroreflex in the development of an early stage of primary hypertension. BRS lower than 3.9 ms/mmHg was found in 5 % of healthy subjects. This value approaches the critical value for the risk of sudden cardiac death in patients after myocardial infarction and corresponds to the value present in hypertensive patients. A decreased BRS and BRSf (baroreflex sensitivity expressed in mHz/mmHg, index independent of the mean cardiac interval), was found not only in children with hypertension, but also in those with white-coat hypertension. This is in accordance with a single interpretation. The decrease of BRS/BRSf precedes a pathological blood pressure increase., 2a_The contribution of obesity and BRS/BRSf to the development of hypertension in adolescents was also compared. Both factors reach a sensitivity and a specificity between 60 % and 65 %, but there is no correlation between the values of the body mass index and BRS either in the group of hypertensive patients or in healthy controls. If a receiver operating curve (sensitivity versus specificity) is plotted for both values together using logistic regression analysis, a sensitivity higher than 70 % and a specificity over 80 % are reached. This means that low baroreflex sensitivity is an independent risk factor for the development of primary hypertension. Studies demonstrate that adolescents with increased blood pressure and with BRS under 7 ms/mmHg should be given care and intensively motivated to change their lifestyle including a change in diet and increase in physical activity., and N. Honzíková, B. Fišer.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2128. Baroreflex Sensitivity as an Individual Characteristic Feature
- Creator:
- Jíra, M., Závodná, E., Honzíková, N., Nováková, Z., and Fišer , B.
- Type:
- article, model:article, and TEXT
- Subject:
- Baroreflex sensitivity, Reproducibility, and Interindividual variability
- Language:
- English
- Description:
- The reproducibility of baroreflex sensitivity (BRS in ms/mmHg; BRSf in mHz/mmHg) determined with respect to the coherence between the variability in systolic blood pressure (SBP) and inter-beat intervals (IBI) or heart rate (HR) was tested. SBP and IBI were recorded beat-to-beat for 5 min (Finapres, breathing at 0.33 Hz) in 116 subjects (aged 19-24 years) sitting at rest three times in periods of one week. BRS and BRSf was determined by a cross-spectral method in a frequency range of 0.067-0.133 Hz. Eight indices were evaluated: BRS0.1Hz/BRSf0.1Hz - the value at a frequency of 0.1 Hz; BRSCOHmax/BRSfCOHmax - the value at maximum coherence; BRSWcoh/BRSfWcoh - weighted value with respect to coherence values in the whole frequency range; BRSWPcoh/BRSWPcoh - weighted value with respect to coherence for frequencies with coherence above 0.5. All indices revealed a lower intraindividual than interindividual variability (p<0.001). The individual mean values of BRS or BRSf correlated (p<0.001) with standard deviation of their individual values for all indices. Baroreflex sensitivity is an individual characteristic feature with the highest reproducibility at its low values in spite of its resting variation. Reproducibility is not influenced by modification of the spectral method used.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2129. Baroreflex sensitivity determined by spectral method and heart rate variability, and two-years mortality in patients after myocardial infarction
- Creator:
- Nataša Honzíková, Bořivoj Semrád, Fišek, B., and Růžena Lábrová
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, infarkt myokardu, myocardial infarction, baroreflex sensitivity, spectral analysis, cardiac death, risk stratification, 14, and 612
- Language:
- English
- Description:
- Sympathetic overactivity and low parasympathetic activity is an autonomic dysfunction (AD) which enhances cardiac mortality. In the present study, the impact of AD on the mortality in patients after myocardial infarction was evaluated. We examined 162 patients 7-21 days after myocardial infarction, 20 patients of whom died in the course of two years. Baroreflex sensitivity (BRS) was estimated by spectral analysis of spontaneous fluctuations of systolic blood pressure and cardiac intervals (Finapres, 5 min recording, controlled breathing 20/min). The heart rate variability was determined as SDNN index (mean of standard deviations of RR intervals for all 5-min segments of 24-hour ECG recordings). BRS < 3 ms/mm Hg and/or SDNN index < 30 ms were taken as markers of AD. The risk stratification was performed according to the number of the following standard risk factors of increased risk of cardiac mortality (SRF): ejection fraction < 40 %, positive late potentials and the presence of ventricular extrasystoles > 10/h. No difference in mortality between patients with AD (4 %) and without AD (4.5 %) was found in 92 patients without SRF, the mortality in 6 patients with three SRF was 66.6 %. Five of these patients had AD. Out of 64 patients with one or two SRF, 32 had AD. The mortality of patients without AD was 6.25 % and 31.2 % of those with AD (p<0.025). It is concluded that AD enhanced two-years mortality five fold in our patients with moderate risks., N. Honzíková, B. Semrád, B. Fišer, R. Lábrová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2130. Baroreflex sensitivity during psychological stress
- Creator:
- Al-Kubati, Mohamed A. A., Fišer, B., and Seigelová, J.
- Type:
- article, model:article, and TEXT
- Subject:
- baroreflex sensitivity, exercise, psychological stress, blood pressure, and heart rate
- Language:
- English
- Description:
- The aim of this study was to analyse the changes of baroreflex sensitivity (BRS) and their relation to changes of heart rate and blood pressure in medical students during moderate psychological stress brought about by oral examination. The changes of BRS during the stress were compared with the changes during light physical exercise. Thirty three students were examined 30 min before and 30 min after the exam. Thirty-nine students of control group were examined at rest and during light exercise. Blood pressure was noninvasively recorded by Peňáz method at rate-controlled breathing (0.33 Hz). The BRS [ms/mm Hg] and BRSf [Hz/mm Hg] were calculated by spectral analysis of spontaneous fluctuations of blood pressure and inter-beat intervals (IBI). BRS before examination (7.12 ms/mm Hg) was significantly lower than after the oral exam (8.77 ms/mm Hg, p<0.05). The difference between BRS in the test group after the oral exam and the control group at rest (10.78 ms/mm Hg) was not significant. BRS during light exercise (7.44 ms/mm Hg) corresponded to the value during psychological stress. The values of BRSf did not change during psychological stress (before: 0.0182 Hz/mm Hg; after: 0.0182 Hz/mm Hg) and exercise (rest: 0.0158 Hz/mm Hg; exercise: 0.0144 Hz/mm Hg). Correlation between BRS or BRSf and blood pressure were not found. A significant negative correlation (r = -0.404, p<0.05) between BRSf and the increase of diastolic blood pressure during stress was observed. It is concluded that BRSf remained constant during psychological stress and exercise, and differed essentially from that in hypertensive subjects.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public