The effects of blocking ventromedial hypothalamic nucleus (VMH) muscarinic cholinoceptors on cardiovascular responses were investigated in running rats. Animals were anesthetized with pentobarbital sodium and fitted with bilateral cannulae into the VMH. After recovering from surgery, the rats were familiarized to running on a treadmill. The animals then had a polyethylene catheter implanted into the left carotid artery to measure blood pressure. Tail skin temperature (Ttail), heart rate, and systolic, diastolic and mean arterial pressure were measured after bilateral injections of 0.2 μl of 5 × 10−9 mol methylatropine or 0.15 M NaCl solution into the hypothalamus. Cholinergic blockade of the VMH reduced time to fatigue by 31% and modified the temporal profile of cardiovascular and Ttail adjustments without altering their maximal responses. Mean arterial pressure peak was achieved earlier in methylatropine-treated rats, which also showed a 2-min delay in induction of tail skin vasodilation, suggesting a higher sympathetic tonus to peripheral vessels. In conclusion, muscarinic cholinoceptors within the VMH are involved in a neuronal pathway that controls exercise-induced cardiovascular adjustments. Furthermore, blocking of cholinergic transmission increases sympathetic outflow during the initial minutes of exercise, and this higher sympathetic activity may be responsible for the decreased performance., S. P. Wanner ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Physical training (PT) is beneficial in cardiovascular diseases associated with NO deficiency such as coronary disease, hypertension, etc. However, it is not known whether PT can also prevent pathological conditions associated with excess NO and fall of blood pressure (BP) such as acute myocardial infarction (AMI). The aim was to compare the effect of AMI on BP and functional state of the endothelium in rats trained by swimming and in untrained animals. After AMI, BP fell from 110±2 to 74±4 mm Hg (p<0.05), the endothelium-dependent relaxation increased from 37±4 to 66±6 % (p<0.05) and the extent of contraction suppression by the endothelium was significantly greater than in the controls. PT itself increased the endothelium-dependent relaxation of rat aorta but left BP unaffected. PT limited the AMI-induced fall of BP to 87±3 mm Hg, the endothelium- dependent relaxation to 53±4 % and prevented the hyporesponsiveness of the aorta to norepinephrine. We suggest that the protective effect of PT is related to inhibition of inducible NO synthase by a negative feedback mechanism.
This review presents experimental data on the perinatal significance of the recently developed concept of physical water compartments. This concept implies that in addition to the compartmentalization of body water into the intra- and extracellular spaces, motionally distinct water fractions – designated as physical water compartments – are also of importance in the neonatal body fluid redistribution. H1-NMR spectroscopy provides a quantitative estimate of tissue water fractions with different mobility as multicomponent analysis of the T2 relaxation decay curves allows us to determine the fast and slow relaxing components of the curves corresponding to the bound and free fractions of tissue water. Using this method, free and bound water fractions were measured in fetal and neonatal rabbit tissues (skin, skeletal muscle, liver, brain, lung) at different stages of maturity and under conditions of various fluid intake. It has been demonstrated that water mobility in individual fetal/neonatal tissues varies greatly and there is a general tendency of increasing free water at the expense of bound water fraction with progressing maturation. This tendency appears to be accelerated in the immediate postnatal period when the tissue water content is markedly reduced. The importance of hyaluronan in this process has also been addressed as the hyaluronan content is markedly elevated in the fetal/neonatal tissues and due to its polyanionic, hydrophilic nature it has been claimed to play a prominent but not clearly defined role in the control of tissue hydration.
The aim of this paper is to increase the stability of buildings and structures to natural disasters by modifying the Georgian clays into cement concrete filler by creation-using of rehydro-liming pozzolanization technology. The risk of damage-destruction of buildings and structures caused by earthquakes, sea storms, floods, mudflows, has increased in the world. Risks can be prevented by increasing of building and structure stability by reducing the anisotropy of cement concrete strength. To do this: Aqueous aluminosilicate minerals of clays, while dehydrating preserving habitus, are modified into a void containing (...mAl2O3∙nSiO2..) base minerals in which, after mixing in cement concrete while rehydro-liming, Ca(OH)2 is sorbed. The tobermorite, stratlingite, generated in filler, together with cement ettringite form fiber-needle-flaky habit clusters by modifying the structure of cement concrete with 3D self-nano-reinforcement, by reducing the anisotropy of strength - by increasing of stability to loads with variable direction-magnitude. It has been proven that in order to prevent risks of catastrophe, it is possible to use modification of Georgian clays by thermal dehydration in cement concrete technologies, which will create the preconditions for cement concrete pozzolanization by rehydro-liming, so the study of the basics of this process is actual., Rajden Skhvitaridze, Elena Shapakidze, IIoseb Gejadze, Merab Abazadze, Malxaz Turdzeladze, Teimuraz Cheishvili and Akaki Skhvitaridze., and Obsahuje bibliografii
The paper presents a theory of information systems based on advanced analogies with both classical and quantum physical models. In the first step the information analogies with magneto-electric circuits are introduced and the information parameters are defined under this inspiration. Well-known potential and flow values (e.g. potential and kinetic energy, voltage and electrical current, etc.) are transformed into information values, "information content" and "information flow". In the second step the quantum information models are introduced together with values "wave information flow" and "wave information content". By using these variables, the complex information models are described in more detail together with illustrative examples.
The paper presents the results of our effort to reveal objective parameters for evaluation of the spa treatment for patients with anxiety-depressive disorders. The study was based on our previous experience with neuroactive steroids and neurosteroids, which play a crucial role in the psychological well-being of patients by maintaining balance of the organism. A total number of 94 steroids were determinated in a group of 70 female patients diagnosed with anxiety-depressive disorders. Patients underwent a month spa treatment while maintaining unchanged medication dosing with SSRI (selective serotonin reuptake inhibitors). The other investigated factors contributing to improving the health of treated subjects were amino-acid homocysteine and serotonin. The blood samples were collected at the beginning and the end of the spa treatment. Serotonin in all patients increased by a relative 23 % (results given as relative differences in percent), while homocysteine decreased by 17.1 %. Statistically significant increases were found in 21 steroids, which indicate activation of the adrenal cortex. It can be assumed, that the overall improvement in the mental condition of patients, which was proved by questionnaire from Knobloch and Hausner, the increase in immune suppressive substances and anti-autoimmune responses, will maintain for a longer time after the spa treatment., M. Bicikova, L. Macova, L. Kolatorova, M. Hill, J. Novotny, D. Jandova, L. Starka., and Obsahuje bibliografii