This research was a prospective, cross-sectional observational study of 128 health workers in the central part of the Republic of Serbia. The study surveyed health workers (physicians, pharmacists ...and nurses) who worked during peaks of the COVID-19 pandemic in the Republic of Serbia in June and November 2020. The Maslach Burnout Survey for Medical Personnel addresses three scales: (a) emotional exhaustion (EE) measures feelings of being emotionally overextended and exhausted by one’s work; (b) depersonalization (DP) measures an unfeeling and impersonal response toward recipients of one’s service, care treatment, or instruction; and (c) personal accomplishment (PA) measures feelings of competence and successful achievement in one’s work. Linear regression and the chi-square test were used to test a relationship between the input variables (x) and the single output variable (y). We can conclude that most health workers had a high degree of emotional exhaustion, but also a low degree of depersonalization and a high degree of sense of personal achievement. Nurses and physicians had similar answers on the pandemic during their work, but pharmacists had different answers.
The aim of this study was to examine and compare the effects of the acute administration of verapamil or amlodipine as representatives of the calcium channel blockers or nicorandil as a ...representative of the mitochondrial ATP-dependent potassium (K
ATP
) channel opener to cardiac contractility, coronary flow, and oxidative stress markers on ischemia/reperfusion injury in the isolated rat heart. The hearts of adult male
Wistar albino
rats (
n
= 60 total, 12 per group) were divided into five groups, two controls (preconditioning with Krebs–Henseleit solution) and three experimental depending on acute administrated pharmacological agents (0,63 µmol/L of verapamil, 0,1 µmol/L of amlodipine, and 200 µmol/L of nicorandil). After stabilization and 5 min of preconditioning in experimental groups, hearts from I/R control and all experimental groups underwent global ischemia (20 min) and reperfusion (30 min). Hearts from sham group were continuously followed for 50 min, after stabilization period. Cardiodynamic parameters and coronary flow were recorded at the end of stabilization (S), at the last minute of pharmacological preconditioning (P) and at intervals of 5 min after global ischemia, during reperfusion, or in case of sham group during 20–50 min after stabilization. At the same intervals, we collected coronary venous effluent from which we spectrophotometrically measured the parameters of oxidative stress: the index of lipid peroxidation, superoxide anion radical, hydrogen peroxide, and nitrite. In summary, our findings clearly indicate that the blocking of the calcium channel or the activation of K
ATP
may mediate the protective effect of myocardial preconditioning. The ex vivo results showed that all examined drugs after ischemia and reperfusion have beneficial cardioprotective properties associated with lower values of major pro-oxidative molecules. Obtained effects seem to be the most convincible in case of nicorandil.
This study was aimed to assess the impact of aerobic and anaerobic type of exercise on blood pressure and redox status in normotensive and hypertensive rats. After 1 week of preconditioning feeding ...and 1 week of preconditioning running regimen, Wistar albino rats (
n
= 72; bw: 270 ± 50 g) were randomly assigned to three groups according to running protocol (high-intensity interval training (HIIT) or moderate-intensity training (MIT)): sedentary control, MIT, HIIT; spontaneous hypertensive sedentary control (SHR), SHR + MIT and SHR + HIIT. Blood pressure (BP) measurement was performed by a tail-cuff noninvasive method BP system. After 48 h of rest following the final training, the rats were fasted for 24 h and sacrificed under ketamine/xylazine anesthesia and blood samples were collected. The level of the next prooxidants were measured: superoxide anion radical (O
2
−
); hydrogen peroxide (H
2
O
2
); nitrite level (NO
2
−
) and index of lipid peroxidation (thiobarbituric acid reactive substances), and the activity of antioxidative enzymes: reduced glutathione (GSH) superoxide dismutase (SOD) and catalase (CAT) activity. After the last week of running, HIIT strongly affected SP, DP, and HR in SHR rats compared to other hypertensive rats, as well as after MIT in normotensive conditions. We have found that HIIT training protocol induced a higher increase of O
2
−
and H
2
O
2
as compared to MIT. Findings of the present study pointed out that contrary to normotensive conditions, in hypertensive conditions both training regimes reduced the BP levels, which was more prominent in case of HIIT. In addition, MIT seems to be connected with milder disturbance of pro-oxidant production and better antioxidant response.
Diallyl trisulfide (DATS) is distinguished as the most potent polysulfide isolated from garlic. The aim of our study was to investigate effects of oral administration of DATS on healthy and diabetic ...rats, with special attention on heart function. Rats were randomly divided into four groups: CTRL (healthy rats), DATS (healthy rats treated with DATS), DM (diabetic rats), DM + DATS (diabetic rats treated with DATS). DATS (40 mg/kg of body weight) was administered every other day for 3 weeks, at the end of which rats underwent echocardiography, glycemic measurement and redox status assessment. Isolated rat hearts were subjected to 30 min global ischemia and 60 min reperfusion, after which heart tissue was counterstain with hematoxylin and eosin and cardiac Troponin T staining (cTnT), while expression of Bax, B cell lymphoma 2 (Bcl-2), caspase-3, caspase-9 and superoxide dismutase-2 were examined in the left ventricle. DATS treatment significantly reduced blood glucose levels of diabetic rats, and improved cardiac function recovery, diminished oxidation status, attenuated cardiac remodeling and inhibited myocardial apoptosis in healthy and diabetic rats. DATS treatment causes promising cardioprotective effects on ex vivo-induced ischemia/reperfusion (I/R) injury in diabetic and healthy rat heart probably mediated by inhibited myocardial apoptosis. Moreover, appropriate DATS consumption may provide potential co-therapy or prevention of hyperglycemia and various cardiac complications in rats with DM.
Three selective and most used inhibitors of PDE-5-sildenafil, vardenafil and tadalafil- have been successfully used for the treatment of erectile dysfunction. Erectile dysfunction and cardiovascular ...diseases might be considered as two dissimilar clinical signs of the identical systemic disease. PDE-5 inhibitors can through different models and mechanisms induce vasodilation, decrease apoptosis and cell proliferation, and they are widely present in various tissues that make them promising targets in a range of cardiovascular diseases.
PubMed was explored to identify papers published from 1990-2019, presenting data for the most used PDE-5 inhibitors (sildenafil, tadalafil or vardenafil) in treatment of cardiovascular diseases.
This article analyses the therapeutic potentials of PDE-5 inhibitors in cardiovascular diseases and discusses mechanisms, possible risks and limitations. Comparable to earlier studies, newer studies suggest cardioprotective effects of PDE-5 inhibitors, which include different models and mechanisms and do not indicate an increased rate of significant cardiovascular adverse reactions. Dissimilarity in the pharmacokinetics and pharmacodynamics of PDE-5 inhibitors are significant to their risk- benefit profile and clinical use. Some of the studies suggesting infarct size reduction after PDE-5 inhibition described the especially close dose-effect relation, other studies dosage adaptation in drug- drug interactions.
PDE-5 inhibitors indicate the encouraging useful effects by ischemia/reperfusion injury, myocar-dial infarction, cardiac hypertrophy, cardiomyopathy and systolic and diastolic congestive heart failure. Therefore, this and similar reviews can help for additional clinical targeting in the therapy of cardiovascular diseases.
This study aimed to assess the impact of high-intensity interval training (HIIT) vs. moderate-intensity continuous training (MIT) on cardiodynamic parameters in isolated rat heart. Wistar albino rats ...were randomly assigned to groups according to running protocol: sedentary control, MIT, and HIIT; spontaneous hypertensive rat (SHR) sedentary control, SHR + MIT, and SHR + HIIT. HIIT groups performed the running in 5 sprints × 45–55 m/min for 30–90 s, with 2 min of rest after each sprint, while MIT groups performed the running of 10–15 m/min for 1 h with 3 min of rest every 100 m; both protocols were implemented 5 days/week over 4 weeks with 1 week of adaptation before protocols started. Isolated rat hearts were perfused according to Langendorff technique at gradually increased coronary perfusion pressures (40–120 cmH
2
O). Using a sensor placed in the left ventricle, we registered maximum and minimum rate of pressure development in the left ventricle, systolic and diastolic left ventricular pressure, and heart rate. Coronary flow was measured flowmetrically. MIT was connected with cardiac depression in normotensive conditions, while HIIT leads to cardiac depression in hypertensive rats. HIIT induced more significant increase of contractile and relaxation parameters of the isolated rat heart, especially in hypertensive animals.
The aim of our study was to examine the effects of different dietary strategies, high-fat (HFd) or standard diet (Sd) alone or in combination with standardized oral supplementation (0.45 mL/kg/day) ...of Aronia melanocarpa extract (SAE) in rats with metabolic syndrome (MetS). SAE is an official product of pharmaceutical company Pharmanova (Belgrade, Serbia); however, the procedure for extraction was done by EU-Chem company (Belgrade, Serbia). Rats were divided randomly into six groups: control with Sd, control with Sd and SAE, MetS with HFd, MetS with HFd and SAE, MetS with Sd and MetS with Sd and SAE during 4 weeks. At the end of the 4-week protocol, cardiac function and liver morphology were assessed, while in the blood samples glucose, insulin, iron levels and systemic redox state were determined. Our results demonstrated that SAE had the ability to lower blood pressure and exert benefits on in vivo and ex vivo heart function. Moreover, SAE improved glucose tolerance, attenuated pathological liver alterations and oxidative stress present in MetS. Obtained beneficial effects of SAE were more prominent in combination with changing dietary habits. Promising potential of SAE supplementation alone or in combination with different dietary protocols in triggering cardioprotection should be further examined in future.
The aim of our study was to investigate the influence of 12 weeks of consumption of chokeberry extract on redox status, body composition, lipid profile, and biochemical parameters in active handball ...players. The study included 16 handball players aged 16-24 years (20.26 ± 2.86 years). Every morning before training, players received 30 mL of liquid chokeberry extract for 12 weeks during the regular competition season. The research consisted of morphofunctional and biochemical testing, which was performed at three points (at the beginning of the study and at 6 and 12 weeks after extract consumption). After the chokeberry extract treatment, we observed significant changes in three main aspects. The 12 week supplementation with chokeberry extract decreased the levels of prooxidants (TBARS and nitrites) and increased catalase activity. Analyzing the dynamic of body composition showed a decrease in body fat (9.4 ± 0.5 vs. 7.3 ± 0.6 kg) as well as its percent in a body (11.4 ± 0.4% vs. 8.8 ± 0.4%). On the other hand, the analysis showed an increase of high-density lipoprotein (1.3 ± 0.3 vs. 1.6 ± 0.2 mmol/L) and hemoglobin (144.4 ± 11.7 vs. 151.7 ± 9.9 g/L) after 6 weeks of treatment. At the same time, a decrease in leukocytes (7.2 × 10
± 2.8 vs. 6.5 ± 1.2 × 10
/L) and an increase in red blood cells count (4.9 ± 0.4 × 10
vs. 5.5 ± 0.5 × 10
/L) were observed. Overall, these results emphatically show that the use of chokeberry extract dietary supplement induced a wide range of beneficial effects in the examined group of athletes.
(1) Background: the purpose of this study was a preliminary analysis of current methods of online teaching at the Faculty of Medical Sciences, University of Kragujevac, Republic of Serbia, in order ...to define the attitudes of biomedical students about education during the COVID-19 pandemic and to validate of the education medical questionnaire (eMedQ), a new tool for the assessment of the students’ perceptions about digital education. (2) Methods: this was a qualitative cross-sectional observational study that used the originally developed 45-item questionnaire (eMedQ) as an assessment instrument conducted on biomedical students (n = 209) of all study years at the Faculty of Medical Sciences, University of Kragujevac (Republic of Serbia), during winter semester or between September 2021 and January 2022. (3) Results: In this study, a Cronbach’s alpha value of 0.904 was obtained, which indicated good internal consistency; the correlation matrix revealed many coefficients greater than 0.3, denoting high correlations between the items. The Kaiser–Meyer–Olkin measure of sampling adequacy was 0.866 and Bartlett’s test of sphericity was significant (p < 0.001). The PCA revealed the presence of seven components with characteristic values over one, while three factors explained the highest percentage of variance. (4) Conclusions: this research developed and validated a new tool for evaluation of biomedical student perceptions about digital education.
Summary
This research is designed to test the hypothesis that elevated homocysteine (Hcy) levels in vivo, caused by a deficit in vitamin B complex, promote changes in cardiac function and redox ...status that lead to heart failure. In order to conduct the study, we used adult male Wistar albino rats (n = 30; 4 weeks old; 100 ± 15 g body weight). Hyperhomocysteinaemia (HHcy) in these animals was achieved by dietary manipulation. For 4 weeks, the animals were fed with a standard rodent chow (control, CF), a diet enriched in methionine with no deficiency in B vitamins (i.e., folic acid, B6 and B12) (HMNV) or a diet enriched in methionine and deficient in B vitamins (HMLV). After 28 days of dietary manipulation, all animals were killed. The rat hearts were isolated and retrogradely perfused according to the Langendorff technique at a gradually increasing perfusion pressure. We found a negative correlation between elevated serum Hcy and total body and heart weight. The maximum rate of left ventricular pressure development was significantly increased in the HMNV group compared with in the other groups. Systolic left ventricular pressure was significantly changed in all groups. HHcy induces remodelling of the cardiac tissues, as moderate HHcy is associated with more prominent interstitial and perivascular fibrosis. Our results suggest that a high methionine diet without vitamin B complex causes profound negative effects associated with HHcy.