Physiological research / Academia Scientiarum Bohemoslovaca (PHYSIOL RES)

Publications in this journal

• Article: Urbancova (Knotkova) H, Hník P, Vejsada R. Bone fracture induces reflex muscle atrophy which is sex-dependent. Physiological Research, 1993, 42:35-40.

  • Urbancova (Knotkova) H, Hník P, Vejsada R
  Physiological research / Academia Scientiarum Bohemoslovaca 04/2013;
• Source

  Available from: psu.edu

  Article: Animal models in the study of exercise-induced cardiac hypertrophy.

  Y Wang, U Wisloff, O J Kemi
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  ABSTRACT: Exercise training-induced cardiac hypertrophy occurs following a program of aerobic endurance exercise training and it is considered as a physiologically beneficial adaptation. To investigate the underlying biology of physiological hypertrophy, we rely on robust experimental models of exercise training in laboratory animals that mimic the training response in humans. A number of experimental strategies have been established, such as treadmill and voluntary wheel running and swim training models that all associate with cardiac growth. These approaches have been applied to numerous animal models with various backgrounds. However, important differences exist between these experimental approaches, which may affect the interpretation of the results. Here, we review the various approaches that have been used to experimentally study exercise training-induced cardiac hypertrophy; including the advantages and disadvantages of the various models.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59(5):633-44.
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  Available from: cas.cz

  Article: Calretinin expression in the mammalian neocortex: a review.

  F Barinka, R Druga
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  ABSTRACT: In the mammalian neocortex, the calcium-binding protein calretinin is expressed in a subset of cortical interneurons. In the recent years, research on interneurons is one of the most rapidly growing fields in neuroscience. This review summarizes the actual knowledge of the functions of calretinin in neuronal homeostasis and particularly of the distribution, connectivity and physiological properties of calretinin expressing interneurons in the neocortex of rodents and primates, including humans. The possible neuroprotective role of calretinin and the presumed "resistance" of calretinin-expressing interneurons to various pathological processes are also discussed.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59(5):665-77.
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  Available from: psu.edu

  Article: Experimental methods for simultaneous measurement of action potentials and electrograms in isolated heart.

  J Kolárová, K Fialová, O Janousek, M Nováková, I Provazník
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  ABSTRACT: 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 dual-wavelength 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.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59 Suppl 1:S71-80.
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  Available from: psu.edu

  Article: Holism and life manifestations: molecular and space-time biology.

  J Krecek
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  ABSTRACT: Appeals of philosophers to look for new concepts in sciences are being met with a weak response. Limited attention is paid to the relation between synthetic and analytic approach in solving problems of biology. An attempt is presented to open a discussion on a possible role of holism. The term "life manifestations" is used in accordance with phenomenology. Multicellular creatures maintain milieu intérieur to keep an aqueous milieu intracellulair in order to transform the energy of nutrients into the form utilizable for driving cellular life manifestations. Milieu intérieur enables to integrate this kind of manifestations into life manifestations of the whole multicellular creatures. The integration depends on a uniqueness and uniformity of the genome of cells, on their mutual recognition and adherence. The processes of ontogenetic development represent the natural mode of integration of cellular life manifestations. Functional systems of multicellular creatures are being established by organization of integrable cells using a wide range of developmental processes. Starting from the zygote division the new being displays all properties of a whole creature, although its life manifestations vary. Therefore, the whole organism is not only more than its parts, as supposed by holism, but also more than developmental stages of its life manifestations. Implicitly, the units of whole multicellular creature are rather molecular and developmental events than the cells per se. Holism, taking in mind the existence of molecular and space-time biology, could become a guide in looking for a new mode of the combination of analytical and synthetic reasoning in biology.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59(2):157-63.
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  Available from: psu.edu

  Article: Effects of different sleep restriction protocols on sleep architecture and daytime vigilance in healthy men.

  H Wu, W S Stone, X Hsi, J Zhuang, L Huang, Y Yin, L Zhang, Z Zhao
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  ABSTRACT: Sleep is regulated by complex biological systems and environmental influences, neither of which is fully clarified. This study demonstrates differential effects of partial sleep deprivation (SD) on sleep architecture and psychomotor vigilance task (PVT) performance using two different protocols (sequentially) that each restricted daily sleep to 3 hours in healthy adult men. The protocols differed only in the period of sleep restriction; in one, sleep was restricted to a 3-hour block from 12:00 AM to 3:00 AM, and in the other, sleep was restricted to a block from 3:00 AM to 6:00 AM. Subjects in the earlier sleep restriction period showed a significantly lower percentage of rapid-eye-movement (REM) sleep after 4 days (17.0 vs. 25.7 %) and a longer latency to the onset of REM sleep (L-REM) after 1 day (78.8 vs. 45.5 min) than they did in the later sleep restriction period. Reaction times on PVT performance were also better (i.e. shorter) in the earlier SR period on day 4 (249.8 vs. 272 ms). These data support the view that earlier-night sleep may be more beneficial for daytime vigilance than later-night sleep. The study also showed that cumulative declines in daytime vigilance resulted from loss of total sleep time, rather than from specific stages, and underscored the reversibility of SR effects with greater amounts of sleep.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59(5):821-9.
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  Available from: psu.edu

  Article: Analysis of the electrical heart field.

  O Kittnar, M Mlcek
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  ABSTRACT: There are three basic procedures used for an assessment of the electrical heart field from the body surface: standard electrocardiography, vectorcardiography, and body surface potential mapping (BSPM). BSPM has two major advantages over both other methods: 1) it allows exploring the entire chest surface, thus providing all the information on the cardiac electric field available at the body surface; 2) it is more sensitive in detecting local electrical events, such as local conduction disturbances or regional heterogeneities of ventricular recovery. Nevertheless the results obtained using BSPM procedure cannot answer all questions about real causality of detected changes of the electrical heart field. We tried therefore to use mathematical model of the electrical field in order to answer these questions. A simple and anatomical forward calculation model was used to test the hypothesis whether the altered position of the heart could explain heterogeneity of repolarization at late stages of pregnancy in humans. The hypothesis was declined. Further findings included: A. Repolarization duration (represented by QT interval) in healthy subjects are distributed regularly and predictably on the body surface carrying no information about local pathology. B. At any systemic analysis of ventricular repolarization, it is vital to consider the regions where any electrode systems record low amplitudes due to methodological, not pathological reasons. C. Anatomical (heterogeneous) model did not yield superior results over simple (homogenous) ones possibly since none reflected the specific torso geometry of individual patients.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59 Suppl 1:S19-24.
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  Available from: psu.edu

  Article: Three-dimensional electrogram in spherical coordinates: application to ischemia analysis.

  O Janousek, J Kolárová, M Nováková, I Provazník
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  ABSTRACT: Three-dimensional electrogram was used for analysis of ischemia manifestation in isolated hearts. Three parameters based on spherical coordination system were used in this study - amplitude of electrical heart vector, its azimuth and elevation. The parameters were presented as a trend. This approach reflected ischemic changes in a manner which can be easily observed and evaluated. Ischemia was analysed in seven isolated hearts of New Zealand white rabbits. It was found that (a) ischemia changes heart electric vector, (b) ischemic preconditioning has a protective effect, and (c) both of these findings can be clearly observed by the proposed method.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59 Suppl 1:S51-8.
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  Available from: psu.edu

  Article: Preclinical atherosclerosis and other determinants of venous thromboembolism in patients with thrombophilias.

  O Auzký, L Pagáčová, T Sejda, J Pitha
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  ABSTRACT: At present, the supposed association between venous thromboembolism and atherosclerosis has yet to be proven. However, no data are available from patients with thrombophilias. We evaluated the association between preclinical atherosclerosis and prevalence of thromboembolic events in patients with thrombophilias. Presence of preclinical atherosclerosis in common carotid and femoral arteries measured by ultrasound was assessed by Belcaro score (based mainly on the presence of plaques) and by measurements of intima media thickness in the same location in 109 patients (43 men, mean age 41.5+/-13 years) with established thrombophilias. Other parameters under the study were age, presence of traditional cardiovascular risk factors, anthropometric and clinical data including blood pressure measurements and medication. The differences between patients with (n=47) and without (n=62) thromboembolic events were assessed by paired t-test and chi square tests. In patients with a history of venous thromboembolism, body mass index and the prevalence of antihypertensive treatment (AT) were significantly higher than in patients without history of thromboembolism (BMI: 26.5+/-5.0 vs. 24.4+/-3.7 kg/m2; p=0.04, AT: 25.5 % vs. 8.1 %; p=0.013). No significant differences between groups were found regarding preclinical atherosclerosis. Overweight and hypertension, but not preclinical atherosclerosis, were more prevalent in patients with thrombophilias suffering from thromboembolism.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59(5):721-8.
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  Available from: psu.edu

  Article: Meal test for glucose-dependent insulinotropic peptide (GIP) in obese and type 2 diabetic patients.

  J Skrha, J Hilgertová, M Jarolímková, M Kunešová, M Hill
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  ABSTRACT: Glucose-dependent insulinotropic peptide (GIP) contributes to incretin effect of insulin secretion which is impaired in Type 2 diabetes mellitus. The aim of this study was to introduce a simple meal test for evaluation of GIP secretion and action and to examine GIP changes in Type 2 diabetic patients. Seventeen Type 2 diabetic patients, 10 obese non-diabetic and 17 non-obese control persons have been examined before and after 30, 60 and 90 min stimulation by meal test. Serum concentrations of insulin, C-peptide and GIP were estimated during the test. Impaired GIP secretion was found in Type 2 diabetic patients as compared with obese non-diabetic and non-obese control persons. The AUCGIP during 90 min of the meal stimulation was significantly lower in diabetic patients than in other two groups (p<0.03). Insulin concentration at 30 min was lower in diabetic than in non-diabetic persons and the GIP action was delayed. The deltaIRI/deltaGIP ratio increased during the test in diabetic patients, whereas it progressively decreased in obese and non-obese control persons. Simple meal test could demonstrate impaired GIP secretion and delayed insulin secretion in Type 2 diabetic patients as compared to obese non-diabetic and non-obese healthy control individuals.
  Physiological research / Academia Scientiarum Bohemoslovaca 01/2010; 59(5):749-55.