Sona Gresova

Pavol Jozef Šafárik University in Košice · Department of Medical Physiology

Experiments should always be based on control values. This assumption fully applies to cardiovascular parameters, such as heart rate (HR) and blood pressure (BP), which are highly sensitive to various external and internal stimuli and can already be significantly altered when an experiment begins. Therefore, it is neces sary to determine which v...

Experiments should always be based on control values. This assumption fully applies to cardiovascular parameters, such as heart rate (HR) and blood pressure (BP), which are highly sensitive to various external and internal stimuli and can already be significantly altered when an experiment begins. Therefore, it is necessary to determine which value...

The cardiovascular system is primarily controlled by the autonomic nervous system, and any changes in sympathetic or parasympathetic activity also have an impact on myocardial activity. Heart rate variability (HRV) is a readily available metric used to assess heart rate control by the autonomic nervous system. HRV can provide information about neur...

In patients with obstructive sleep apnea (OSA) during obstructive events, episodes of hypoxia and hypercapnia may modulate the autonomic nervous system (ANS) by increasing sympathetic tone and irritability, which contributes to sympathovagal imbalance and ultimately dysautonomia. Because OSA can alter ANS function through biochemical changes, we ca...

Heart rate variability (HRV) is commonly used in experimental studies to assess sympathetic and parasympathetic activities. The belief that HRV in rodents reflects similar cardiovascular regulations in humans is supported by evidence, and HRV in rats appears to be at least analogous to that in humans, although the degree of influence of the parasym...

Background: The aim of the study was to compare the continuous glucose monitoring (CGM)-determined glycaemic variability (GV) of pregnant women with gestational diabetes mellitus (GDM) and without GDM (CG; control group). The secondary aim was to evaluate the association between risk factors of diabetes in pregnancy and parameters of glyceamic cont...

It is well known that in patients with obstructive sleep apnea syndrome (OSAS) the apnea-hypopnea index (AHI) is significantly decreased during slow wave sleep (SWS). It used to be explained by the ability of SWS to stabilize the upper airways against collapse. Another explanation, which is the focus of the current study, is that it is just a resul...

Objective: Obstructive sleep apnoea syndrome (OSAS) associated with daytime sleepiness (DS) contributes to a higher incidence of motor vehicle accidents. Validation of fitness to drive in driving license applicants, with special concern regarding OSAS accompanied by excessive DS, became mandatory under new EU legislation in January 2016. The aim o...

Introduction: Validation of fitness to drive in applicants for a driving license, with a special concern regarding OSAS accompanied by excessive daytime sleepiness, became mandatory under new EU legislation in January 2016. The aim of the study was to translate and validate the recommended Questionnaire to screen for OSAS (Q-OSAS) in Slovakia. Mate...

The specific aim of the present study, with respect to dependence on the light–dark (LD) cycle under in vivo conditions in spontaneously breathing rats was to review initial state in electrophysiological parameters that may predict the development of heart rhythm disorders in pentobarbital (40 mg/kg), ketamine–xylazine (100 + 15 mg/kg) and zoletil...

The design and development of experimental, in vivo chronobiological animal models may help reveal some of the relationships between circadian rhythms and biological function, which can be very difficult to study in humans. To perform ethically acceptable cardiovascular research involving animals, the use of general anaesthesia is often necessary....

Zoletil anaesthesia does not affect vital functions; however, there is no literature evidence regarding the effect of zoletil anaesthesia on the circadian rhythm(s) of vital functions. The aims of this study, with respect to dependence on the light-dark (LD) cycle under in vivo conditions in spontaneously breathing zoletil-anaesthetized rats, were...

Administration of anaesthesia may influence specific aspects of in vivo animal experiments and is an especially important consideration for experiments conducted during the daytime. Although chronobiological studies investigating interactions between general anaesthesia and circadian rhythms are sparse, all suggest that general anaesthetic agents h...

Basis: Restless legs syndrome (RLS) is a neurological disorder characterized by throbbing, pulling, creeping, or other unpleasant sensations in the legs and an uncontrollable, and sometimes overwhelming urge to move them. Symptoms occur primarily at night, when a person is relaxing or at rest and can increase in severity during the night. Moving th...

Although it is thought that Obstructive sleep apnea (OSA) is worse during rapid eye movement (REM) sleep than in non-REM (NREM) sleep there are some uncertainties, especially about apnoe-hypopnoe-index (AHI). Several studies found no significant difference in AHI between both sleep stages. However, REM sleep is associated more with side sleeping co...

Various diseases often result in decompensation requiring resuscitation. In infants moderate hypoxia evokes a compensatory augmented breath -- sigh and more severe hypoxia results in a solitary gasp. Progressive asphyxia provokes gasping respiration saving the healthy infant -- autoresuscitation by gasping. A neonate with sudden infant death syndro...

Agonal gasping provoked by asphyxia can save ~15% of mammals even from untreated ventricular fibrillation (VF), but it fails to revive infants with sudden infant death syndrome (SIDS). Our systematic study of airway reflexes in cats and other animals indicated that in addition to cough, there are two distinct airway reflexes that may contribute to...

1) To analyze heart rate variability (HRV) changes, reflecting the sympathovagal balance with secondary hypertension caused by sleep disordered breathing (SDB), compared to healthy controls and essential hypertension without SDB; 2) to compare HRV changes between various degrees of SDB severity; and 3) to test the modification of HRV indices by con...

Nocturnal cardiac arrhythmias (NCA) were analyzed in patients with sleep apnea/hypopnea syndrome (SAHS) and controls. Occurrence and severity of NCA were compared in 33 SAHS patients and 16 control subjects, matched for cardiovascular risk factors. Continuous overnight polysomnography provided ECG, respiratory and sleep parameters for a comparative...

It has been shown previously that the suppression of slow-wave sleep (SWS) markedly reduced insulin sensitivity and led to an impairment of glucose tolerance. We hypothesized that a decreased amount of SWS is a feature peculiar to subjects with type 2 diabetes. A retrospective case-control study analyzed polysomnographic recordings and covariate da...

Re-evaluation of our earlier c-Fos-like immuno-reactive studies and brainstem transection/lesion experiments in over 40 anaesthetized, non-paralyzed cats allowed comparison of two distinct airway defensive reflexes with the distinct generators for inspiration (I) and expiration (E), described recently in juvenile rats. The spiration reflex (AspR) i...

Ambulatory blood pressure monitoring and parallel polysomnographic study were performed in 116 adult males divided into 6 groups. Thirty blood-pressure (BP) and polysomnographic variables were measured to test their usefulness for screening for both arterial hypertension and sleep apnea-hypopnea syndrome (SAHS). The development of severe breathing...

The main functions of the blood are the transport, and delivery of oxygen and nutrients, removal of carbon dioxide and waste products of metabolism, distribution of heat and signals of immune system. They are provided by circulation due to the driving force of the heart. Circulation of the blood depends on its rheological properties of the blood as...

Sleep-disordered breathing (SDB) is often associated with impaired glucose metabolism. The study aimed at assessing immediate effect of CPAP on glucose excursions in type 2 diabetic patients with SDB measured with 72-hour continuous glucose monitoring system (CGMS). 8 type 2 diabetic patients with SDB (men, age 48,13±4,91 years, BMI 34,06±7,41 kg·m...