An unusual finding of schwannoma in the mammary gland of a dog.

Peripheral nerve sheath tumours (PNSTs) are rare in the mammary glands of dogs. Here, we report a case of a schwannoma, composed of two parts, of the mammary gland of a dog. The first part consists of clusters of uncircumscribed, alternating, more concentrated and looser regions.

Measurement of blood pressure in rats: Invasive or noninvasive methods?

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 values are defined as a starting point (i.

An Obstructive Sleep Apnea - A Novel Public Health Threat.

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 can assume that heart rate variability (HRV) will be altered in patients with OSA. Most studies show that in both the time and frequency domains, patients with OSA have higher sympathetic components and lower parasympathetic dominance than healthy controls.

Heart rate variability in male rats.

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 neural (parasympathetic, sympathetic, reflex) and humoral (hormones, thermoregulation) control of myocardial activity.

Sex differences, chronobiology and general anaesthesia in activities of the autonomic nervous system in rats.

New Findings: What is the topic of this review? Changes in heart rate variability in rats with sex differences and the use of different anaesthesia during light-dark cycles. What advances does it highlight? The review highlights and discusses synthesized current results in order to advance knowledge and understanding of sex differences with an emphasis on changes in the autonomic nervous system determined by heart rate variability.

Abstract: Heart rate variability (HRV) is commonly used in experimental studies to assess sympathetic and parasympathetic activities.

General anesthesia and electrocardiographic parameters in in vivo experiments involving rats.

In in vivo cardiovascular or toxicological studies involving rat models, changes in selected electrocardiographic (ECG) parameters are monitored after various interventions to assess the origin and development of heart rhythm disorders. Each ECG parameter has diagnostic significance; as such, commonly evaluated ECG parameters, including heart rate, PR interval, P wave duration, P wave amplitude, QRS complex, QT and QTc interval duration, R wave and T wave amplitude, of rats under various types of general anesthesia were the focus of this study. Studies that performed in vivo cardiovascular or toxicological experiments in rats were retrieved from a search of the Web of Science database for articles published mainly between 2000 and 2021.

Arterial pH and blood gas values in rats under three types of general anesthesia: a chronobiological study.

The aim of study was to review the status of arterial pH, pO(2) and pCO(2) under general anesthesias in dependence on the light-dark (LD) cycle in spontaneously breathing rats. The experiments were performed using three- to four-month-old pentobarbital(P)-, ketamine/xylazine(K/X)- and zoletil(Z)-anesthetized female Wistar rats after a four-week adaptation to an LD cycle (12 h light:12 h dark). The animals were divided into three experimental groups according to the anesthetic agent used: P (light n=11; dark n=8); K/X (light n=13; dark n=11); and Z (light n=18; dark n=26).

Reactive oxygen species and antioxidant defense in human gastrointestinal diseases.

Crohn's disease and ulcerative colitis, known together as inflammatory bowel diseases (IBDs), and celiac disease are the most common disorders affecting not only adults but also children. Both IBDs and celiac disease are associated with oxidative stress, which may play a significant role in their etiologies. Reactive oxygen species (ROS) such as superoxide radicals (O•), hydroxyl radicals (•OH), hydrogen peroxide (HO), and singlet oxygen (O) are responsible for cell death via oxidation of DNA, proteins, lipids, and almost any other cellular constituent.

Dietary intake and ghrelin and leptin changes after sleeve gastrectomy.

Introduction: Surgical intervention in obesity is today the most effective treatment method in high level obesity management. Bariatric interventions not only ensure body weight reduction, but may influence dietary habits.

Aim: To assess changes in adipose hormones and dietary habits in obese patients after sleeve gastrectomy.

Effect of reoxygenation on the electrical stability of the rat heart in vivo: a chronobiological study.

Reoxygenation following hypoxic episodes can increase the risk for the development of ventricular arrhythmias, which, in addition to circadian aspects of reoxygenation arrhythmias has not been studied extensively. The aim of the present study was to evaluate circadian changes in the electrical stability of the rat heart during reoxygenation following a hypoventilatory episode. The electrical stability of the heart, defined in the present study as the ventricular arrhythmia threshold (VAT), was measured at 3 h intervals at clock times 09:00, 12:00, 15:00, 18:00, 21:00, 24:00, 03:00, 06:00 and 09:00 during 20 min hypoventilation (20 breaths/min, tidal volume = 0.

Autonomic nervous system under ketamine/ xylazine and pentobarbital anaesthesia in a Wistar rat model: a chronobiological view.

The aim of the present study was to determine the effect of ketamine/ xylazine and pentobarbital anaesthesia on heart rate variability as a marker of autonomic nervous system activity. The experiments were performed in ketamine/ xylazine (10 mg/kg/15 mg/kg) and pentobarbital (40 mg/kg, i.p.

Effects of sleeve gastrectomy on parameters of lipid and glucose metabolism in obese women - 6 months after operation.

Introduction: Surgical intervention in obesity is today the most effective treatment method in high level obesity management with long-term clinical results and satisfaction of operated patients. Bariatric interventions not only ensure body weight reduction, but may influence lipid and saccharide metabolism as well.

Aim: To monitor the dynamics of changes in selected lipid and glucose metabolism parameters after laparoscopic sleeve gastrectomy (LSG) in obese women.

Chronophysiologic aspects of ECG changes during a systemic asphyxic episode and subsequent reoxygenation in an experimental rat model.

The aim of the study was to evaluate the effect of ventilatory manoeuvres on some ECG parameters as a function of the light-dark (LD) cycle in in vivo conditions. The PQ and QT intervals were measured in ketamine/xylazine-anaesthetized female Wistar rats (100 mg/15 mg/kg, i.m.

Hemorheology and circulation.

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 well as on characteristics of the vessels through which the blood passes.

[Chronobiology and practical medicine].

In present time, to classify the healthy as potencional possibility of the organism to accept variable environment influences without the break of the biological important functions is not satisfactory. Examples from the different field of the clinical medicine refer to importance of the knowledge's of the circadian rhythmicity concerning many diseases, symptoms or significant remissions. Therefore, clinical trials considering the biological variability differ from the convectional studies by assumption that biology of patient is dynamic, that time of the diagnostic test running is significant and that drugs can influence safety and therapeutic effect in the dependence on the day-time.

The effect of hypoxic myocardial preconditioning is highly dependent on the light-dark cycle in Wistar rats.

Background: Cardioprotective effects by hypoxic preconditioning are well known mainly through in vitro experiments. However, the chronobiological aspects of phenomenon of cardioprotection by hypoxic preconditioning have not been studied in in vitro and in vivo experiments, and there are no consistent data regarding the daytime dependence of preconditioning effects.

Aim: To determine the protective effects of myocardial preconditioning applied during the dark (active) part of the day regimen, and to obtain an understanding concerning chronophysiological aspects of this phenomenon in in vivo rat experiments.

Effect of systemic hypoxia and reoxygenation on electrical stability of the rat myocardium: chronophysiological study.

The aim of the study was to determine the dependence of changes in the electrical stability of the heart on the light-dark cycle (LD cycle) in disorders of pulmonary ventilation. The ventricular arrhythmia threshold (VAT) was measured in female Wistar rats (adaptation to the light regime 12:12 h, ketamine/xylazine anesthesia 100 mg/15 mg/kg, i.m.

Ionic hemolysis behavior of erythrocytes in rats of both sexes.

Erythrocyte microrheology changes were measured by cation-osmotic haemolysis in Wistar albino rats of both sexes. Erythrocyte membrane biophysical properties were estimated using the method of cation-osmotic haemolysis (COH) described by Nicak and Mojzis [Comp. Haematol.

Chronophysiological view on changes of the electrical stability of the heart and heart rate under pentobarbital sodium and ketamine/xylazine anesthesia in a hypoventilation-reoxygenation rat model.

Objectives: To determine the effect of the light-dark cycle (LD) and type of anesthetic agent used on changes in the electrical stability of the heart in disorders of pulmonary ventilation.

Methods: The ventricular arrhythmia threshold (VAT) and heart rate (HR) were measured in anesthetized female Wistar rats adapted to an LD regimen of 12 h:12 h (pentobarbital sodium 30 mg/kg, intraperitoneally, or ketamine/xylazine 100 mg/15 mg/kg, intramuscularly; open chest experiments) under artificial normoventilation (tidal volume 1 mL/100 g, respiratory rate 40 breaths/min) and during 20 min of hypoventilation (tidal volume 0.5 mL/100 g, respiratory rate 20 breaths/min) followed by 20 min of reoxygenation.

Preconditioning by hypoventilation increases ventricular arrhythmia threshold in Wistar rats.

Hypoventilation, as one of ventilatory disorders, decreases the electrical stability of the heart similarly as ischemia. If preconditioning by short cycles of ischemia has a cardioprotective effect against harmful influences of a prolonged ischemic period, then preconditioning by hypoventilation (HPC) can also have a similar effect. Anesthetized rats (ketamine 100 mg/kg + xylasine 15 mg/kg i.

Modulatory influences of ventilatory disorders on electrical stability of the rat heart.

It is a known fact that there is a relationship between some ventilatory disorders and the incidence of ventricular arrhythmias. The aim of our study was to show this relation in the circadian dependence in in-vivo rat models. The electrical stability of the heart was measured by ventricular arrhythmia threshold (VAT) at 3h intervals during a 24h period.

[An overview of the regulation of basic functions of the digestive system].

The gastrointestinal system is the gate through which nutritive substances, vitamins, minerals, and fluids enter the body. Proteins, fats and complex carbohydrates are broken down into absorbable units (products of the digestion) in the digestive tract and finally they are absorbed together with vitamins, minerals and water into the blood or the lymph. The digestive and absorptive functions of the gastrointestinal tract depend on the various mechanisms, which adjust the food, put it through the gastrointestinal tract and mix it together with digestive enzymes secreted by the salivary glands, stomach, pancreas, small intestine and with bile.

Relation of ventricular fibrillation threshold to heart rate during normal ventilation and hypoventilation in female Wistar rats: a chronophysiological study.

The aim of our study was to verify the relationship between heart rate (HR) and ventricular fibrillation threshold (VFT) during different types of ventilation in female Wistar rats from the circadian point of view. The experiments were performed under pentobarbital anesthesia (40 mg/kg i.p.

[Circadian rhythm of the ventricular fibrillation threshold in a model of hypoventilation-reoxygenation in female Wistar rats].

Hypoxia, similarly as myocardial ischemia, decreases the electric stability of the heart and thus produces the conditions for the genesis of ventricular arrhythmias within the 24 h period however a prompt restoration of oxygen supply or blood flow within myocardium causes serious ventricular arrhythmias. Therefore the aim of our study was to evaluate the reoxygenation impact on myocardium after hypoventilation in circadian dependence. The experiments were performed in female Wistar rats (pentobarbital anesthesia 40 mg/1 kg i.