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72. Cooling-evoked hemodynamic perturbations facilitate sympathetic activity with subsequent myogenic vascular oscillations via alpha2-adrenergic receptors
- Creator:
- Lin, Y.-H., Liu, Y.-P., Lin, Y.-C., Lee, P.-L., and Tung, C.-S.
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, cold stimulation, power spectral analysis, sympathetic activation, alpha2-adrenoceptors, myogenic vascular oscillations, 14, and 612
- Language:
- English
- Description:
- This study extends our previous work by examining the effects of alpha2 -adrenoceptors under cold stimulation involving the increase of myogenic vascular oscillations as increases of very-low-frequency and low-frequency of the blood pressure variab ility. Forty-eight adult male Sprague-Dawley rats were randomly divided into four groups: vehicle; yohimbine; hexamethonium+yohimbine; guanethidine+yohimbine. Systolic blood pressure, heart rate, power spectral analysis of spontaneous blood pressure and he art rate variability and spectral coherence at very-low-frequency (0.02 to 0.2 Hz), low-frequency (0.2 to 0.6 Hz), and high-frequency (0.6 to 3.0 Hz) regions were monitored using telemetry. Key findings are as follows: 1) Cooling-induced pressor response was attenuated by yohimbine and further attenuated by hexamethonium+yohimbine and guanethidine+yohimbine, 2) Cooling-induced tachycardia response of yohimbine was attenuated by hexame - thonium+yohimbine and guanethidine+yohimbine, 3) Different patterns of p ower spectrum reaction and coherence value compared hexamethonium+yohimbine and guanethi-dine+yohimbine to yohimbine alone under cold stimulation. The results suggest that sympathetic activation of the postsynaptic alpha2-adrenoceptors causes vasoconstriction and heightening myogenic vascular oscillations, in turn, may increase blood flow to prevent tissue damage under stressful cooling challenge., Y.-H. Lin, Y.-P. Liu, Y.-C. Lin, P.-L. Lee, C.-S. Tung., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
73. Cryografts implantation in human circulation would ensure a physiological transition in the arterial wall energetics, damping and wave reflection
- Creator:
- Bia, Daniel, Barra, J. G., Armentano, R. L., Zócalo, Y., Pérez, H., Saldías, M., Álvarez, I., and Cabrera Fischer, E. I.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, viskoelasticita, physiology, viscoelasticity, arterial wall, cryopreservation, buffer function, conduit function, 14, and 612
- Language:
- English
- Description:
- Each artery conduces blood (conduit function, CF) and smoothes out the pulsatility (buffering function, BF), while keeping its wall protected against the high oscillations of the pulse waves (damping function, ξ). These functions depend on each segment viscoelasticity and capability to store and dissipate energy. When a graft/prosthesis is implanted, the physiological gradual transition in the viscoelasticity and functionality of adjacent arterial segments is disrupted. It remains to be elucidated if the cryografts would allow keeping the physiological biomechanical transition. The aim of this study was to evaluate the cryografts capability to reproduce the functional, energetic and reflection properties of patients’ arteries and fresh homografts. Common carotid’s pressure, diameter and wall-thickness were recorded in vivo (15 patients) and in vitro (15 cryografts and 15 fresh homografts from donors). Calculus: elastic (Epd) and viscous (Vpd) indexes, CF, BF, dissipated (WD) and stored (WPS) energy and ξ. The graft-patient’s artery matching was evaluated using the reflection coefficient (Γ) and reflected power (WΓ). Cryografts did not show differences in Epd, Vpd, BF, CF, WD, WPS, and ξ, in respect to fresh homografts and patients’ arteries, ensuring a reduced Γ and WΓ. Cryografts could be considered as alternatives in arterial reconstructions since they ensure the gradual transition of patients’ arteries biomechanical and functional behavior., D. Bia, J. G. Barra, R. L. Armentano, Y. Zócalo, H. Pérez, M. Saldíaz, I. Álvarez, E. I. Cabrera Fischer., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
74. Cytokine profile in cases with premature elevation of progesterone serum concentrations during ovarian stimulation
- Creator:
- Nikolettos, N., Asimakopoulos, B., Frank Köster, Schöpper, B., Schulz, Ch., Caglar, G. S., Efthimiadou, A., Pagonopoulou, O., Klaus Diedrich, and Al-Hasani, S.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, progesteron, růstové faktory, leptin, physiology, progesterone, growth factors, premature elevation of progesterone, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), tumor necrosis factor-α, interleukin IL-1β, interleukin IL-6, 14, and 612
- Language:
- English
- Description:
- The aim of this study was to investigate the concentrations of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), leptin, tumor necrosis factor-α, interleukin (IL)-1β and IL-6, in cycles with a premature rise of serum progesterone. 25 intracytoplasmic sperm injection (ICSI) cycles with (Group 1) and 25 ICSI cycles without a premature progesterone elevation (Group 2) were included. The cut-off value of serum progesterone on the day of human chorionic gonadotropin (hCG) administration was 0.9 ng/ml. The indication for ICSI was male factor infertility exclusively. On the day of hCG injection, serum IL-6, VEGF and bFGF were significantly higher in Group 1 (7.7±24.5 pg/ml, 290.2±161.4 pg/ml and 15.7±8.2 ng/ml respectively) than in Group 2 (1.7±0.7 pg/ml, 175.2±92.1 pg/ml, and 9±1.6 ng/ml respectively). On the day of follicular puncture, serum cytokine concentrations were similar in the two groups. IL-6 intrafollicular concentrations were higher in Group 1 (14.7±20.7 pg/ml) than in Group 2 (9±9.3 pg/ml, p=0.031). There were no differences regarding the ICSI outcome. Patients with serum progesterone above 0.9 ng/ml, have elevated serum concentrations of IL-6, VEGF, and bFGF, as well as elevated intrafollicular concentrations of IL-6. The outcome of ICSI cycles is not associated with premature elevation of progesterone when the cut-off value is set at 0.9 ng/ml., N. Nikolettos, B. Asimakopoulos, F. Köster, B. Schöpper, Ch. Schulz, G. S. Caglar, A. Efthimiadou, O. Pagonopoulou, K. Diedrich, S. Al-Hasani., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
75. Cytokine profile of human septic shock serum inducing cardiomyocyte contractile dysfunction
- Creator:
- Joulin, O., Petillot, P., Labalette, M., Lancel, S., and Neviere, Remi
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, nekróza, stárnutí buněk, human physiology, necrosis, cell aging, heart dysfunction, tumor necrosis factor, interleukin, 14, and 612
- Language:
- English
- Description:
- This study was designed to measure nitrite/nitrate and cytokine levels of serum obtained from septic shock patients and to describe potential depressant effects of human septic serum on rat cardiomyocytes. Serum was prepared from 10 non-septic patients and 10 patients with documented septic shock. Adult rat ventricular myocytes were exposed to 20 % serum in the medium. Cardiomyocyte contractility was assessed by measuring shortening fraction and shortening velocity. Serum levels of nitrite/nitrate, a marker of nitric oxide final metabolites, and cytokines (tumor necrosis factor (TNF)-α, interleukin (IL) 1β , 6, 10, 8 and 12p70) were measured. Compared with serum from non-septic patients, serum of septic shock patients induced rapid reduction of the extent and velocity of shortening in isolated cardiomyocytes. Nitrite/nitrate, TNF-α , IL-1β and IL-12p70 concentrations of tested serum for cardiomyocyte studies were not increased in septic serum compared with controls . In contrast, septic serum that induced a depression of in vitro contractility, had increased levels of IL-6, IL-8 and IL-10. We can conclude that the depression of in vitro contractility induced by septic serum is not directly dependent on elevated levels of nitric oxide metabolites, TNF-α or IL-1β. Our results support the view that other cytokines, including IL-6, IL-8 and IL-10, are potent circulating mediators of myocardial depression in cardiomyocytes., O. Joulin, P. Petillot, M. Labalette, S. Lancel, R. Neviere., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
76. D-galactosamine/lipopolysaccharide-induced hepatotoxicity downregulates sirtuin 1 in rat liver: role of sirtuin 1 modulation in hepatoprotection
- Creator:
- Kemelo, M. K., Wojnarová, L., Nikolína Kutinová-Canová, and Hassan Farghali
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, SIRT1, resveratrol, EX-527, d-galactosamine, lipopolysaccharide, hepatotoxicity, 14, and 612
- Language:
- English
- Description:
- D-Galactosamine/Lipopolysaccharide (D-GalN/LPS) is a well known model of hepatotoxicity that closely resembles acute liver failure (ALF) seen clinically. The role of sirtuin 1 in this model has not yet been documented. However, there have been a number of studies about the cytoprotective effects of resveratrol, a SIRT1 activator, in the liver. This study was aimed at elucidating the roles of SIRT1 protein expression or catalytic activity in DGalN/ LPS model of hepatotoxicity. ALF was induced in male Wistar rats by intraperitoneal injection of D-GalN and LPS. Some groups of animals were pretreated with resveratrol and/or EX-527 (SIRT1 inhibitor). The effects of these treatments were evaluated by biochemical and Western blot studies. D-GalN/LPS treatment was able to induce hepatotoxicity and significantly increase all markers of liver damage and lipid peroxidation. A dramatic decrease of SIRT1 levels in response to D-GalN/LPS treatment was also documented. Resveratrol pretreatment attenuated D-GalN/LPS-induced hepatotoxicity. EX-527 blocked the cytoprotective effects of resveratrol. However, both resveratrol and EX-527 pretreatments did not exhibit any significant effect on SIRT1 protein expression. Collectively, these results suggest that downregulation of SIRT1 expression is involved in the cytotoxic effects of D-GalN/LPS model and SIRT1 activity contributes to the cytoprotective effects of resveratrol in the liver., M. K. Kemelo, L. Wojnarová, N. Kutinová Canová, H. Farghali., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
77. Daily rhythm in rat pineal catecholamines
- Creator:
- Ivan Ahlers, Bernadetta Pástorová, Peter Solár, and Eva Ahlersová
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, rat pineal, catecholamines, daily oscillations, 14, and 612
- Language:
- English
- Description:
- A daily rhythm in the oscillations of pineal dopamine, norepinephrine and epinephrine content was found in male Wistar:Han rats. The acrophases of the oscillations were localized in the first half of the dark period and generally higher values were found in the dark part of the day., I. Ahlers, B. Pástorová, P. Solár, E. Ahlersová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
78. Degenerative Changes of the Vertebral Column in Lithuanian Palaeopopulation /
- Creator:
- Jankauskas, Rimantas
- Type:
- text and články
- Subject:
- Kulturní antropologie. Etnologie. Etnografie, fyziologie, antropologie, společnost středověká, Litva, světové dějiny středověku (do r. 1492), and národnosti, vztahy mezi národnostmi a národní hnutí
- Language:
- English
- Rights:
- unknown
79. Delayed effects of elevated corticosterone level on volume of hippocampal formation in laboratory rat
- Creator:
- Petr Zach, Mrzílková, J., Lenka Řezáčová, Aleš Stuchlík, and Karel Valeš
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, corticosterone, hyppocampus, lateralization, volumetry, long evans rat, 14, and 612
- Language:
- English
- Description:
- We studied delayed effects of elevated plasma levels of corticosterone (Cort) on volumetry, neuronal quantity, and gross marks of neurodegeneration in the hippocampal formation of Long-Evans rats. Animals were exposed to increased CORT levels for three weeks via implanted subcutaneous pellets. Volumetry, neuronal quantification and gros s marks of degeneration were measured seven weeks after the termination of CORT treatment. We observed significant differences in volumes and especially in laterality of hippocampal subfields between control and CORT- treated animals. We found th at the left hippocampus was substantially larger than the right hippocampus in the corticosterone-treated group, but not in the control group. In the control group, on the other hand, right hippocampal volume was markedly higher than all other measured volumes (hippocampal left control, hippocampal left CORT-treated and hippocampal right CORT-treated). Left hippocampal volume did not differ between the groups., P. Zach, J. Mrzílková, L. Řezáčová, A. Stuchlík, K. Valeš., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
80. Depressed cardiac contractility and its postnatal development in rats after chemical sympathectomy
- Creator:
- Jitka Švíglerová, Jitka Kuncová, Lukáš Nalos, Jana Slavíková, and Milan Štengl
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, fyziologie, neuropeptidy, srdce, potkan, physiology, neuropeptids, heart, Rattus norvegicus, chemical sympathectomy, contraction, norepinephrine, 2, and 577
- Language:
- English
- Description:
- This study sought to evaluate whether consumption of polyphenol extract from Cognac (CPC) modulates platelet activation and cardiovascular reactivity in rats. Male Wistar rats were treated daily for 4 weeks by intra-gastric gavage receiving CPC at 80 mg/kg/day or vehicle (5 % glucose). Platelet adhesion and aggregation in response to different activators were assessed. Cardiac and vascular reactivity in response to various agonists as well as NO measurement by electron paramagnetic resonance technique were investigated in isolated heart and thoracic aorta. Oral administration of CPC decreased platelet aggregation induced by ADP but not by collagen. CPC did not affect adhesion to collagen. The chronotropic but not the inotropic response to isoprenaline was reduced without alteration of NO production in hearts from CPC-treated rats. CPC treatment did not affect ex vivo relaxation to acetylcholine nor NO content of rat aorta. CPC did not significantly alter the response to phenylephrine in aorta despite the participation of endothelial vasoconstrictor products. In summary, chronic treatment with CPC has no impact on ex vivo vascular and cardiac reactivity; however, it reduced heart work and platelet aggregation. These data suggest the existence of compounds in Cognac that may decrease the risk of coronary thrombosis and protect against some cardiac diseases., J. Švíglerová, J. Kuncová, L. Nalos, J. Slavíková, M. Štengl., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public