cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.7941374
title: Deficiency of sex hormones does not affect 17-ß-estradiol-induced coronary vasodilation in the isolated rat heart

description: The relaxation of coronary arteries by estrogens in the coronary vascular beds of naive and hypertensive rats has been well described. However, little is known about this action in gonadectomized rats. We investigated the effect of 17-ß-estradiol (E2) in coronary arteries from gonadectomized rats, as well as the contributions of endothelium-derived factors and potassium channels. Eight-week-old female and male Wistar rats weighing 220-300 g were divided into sham-operated and gonadectomized groups (n=9−12 animals per group). The baseline coronary perfusion pressure (CPP) was determined, and the vasoactive effects of 10 μM E2 were assessed by bolus administration before and after endothelium denudation or by perfusion with NG-nitro-L-arginine methyl ester (L-NAME), indomethacin, clotrimazole, L-NAME plus indomethacin, L-NAME plus clotrimazole or tetraethylammonium (TEA). The CPP differed significantly between the female and sham-operated male animals. Gonadectomy reduced the CPP only in female rats. Differences in E2-induced relaxation were observed between the female and male animals, but male castration did not alter this response. For both sexes, the relaxation response to E2 was, at least partly, endothelium-dependent. The response to E2 was reduced only in the sham-operated female rats treated with L-NAME. However, in the presence of indomethacin, clotrimazole, L-NAME plus indomethacin or L-NAME plus clotrimazole, or TEA, the E2 response was significantly reduced in all groups. These results highlight the importance of prostacyclin, endothelium-derived hyperpolarizing factor, and potassium channels in the relaxation response of coronary arteries to E2 in all groups, whereas nitric oxide may have had an important role only in the sham-operated female group.
DOI: 10.6084/m9.figshare.7941368
title: Exercise improved lipid metabolism and insulin sensitivity in rats fed a high-fat diet by regulating glucose transporter 4 (GLUT4) and musclin expression

description: This study aimed to evaluate the effects of exercise training on triglyceride deposition and the expression of musclin and glucose transporter 4 (GLUT4) in a rat model of insulin resistance. Thirty male Sprague-Dawley rats (8 weeks old, weight 160±10 g) were fed a high-fat diet (40% calories from fat) and randomly divided into high-fat control group and swimming intervention group. Rats fed with standard food served as normal control. We found that 8-week swimming intervention significantly decreased body weight (from 516.23±46.27 to 455.43±32.55 g) and visceral fat content (from 39.36±2.50 to 33.02±2.24 g) but increased insulin sensitivity index of the rats fed with a high-fat diet. Moreover, swimming intervention improved serum levels of TG (from 1.40±0.83 to 0.58±0.26 mmol/L) and free fatty acids (from 837.80±164.25 to 556.38±144.77 μEq/L) as well as muscle triglycerides deposition (from 0.55±0.06 to 0.45±0.02 mmol/g) in rats fed a high-fat diet. Compared with rats fed a standard food, musclin expression was significantly elevated, while GLUT4 expression was decreased in the muscles of rats fed a high-fat diet. In sharp contrast, swimming intervention significantly reduced the expression of musclin and increased the expression of GLUT4 in the muscles of rats fed a high-fat diet. In conclusion, increased musclin expression may be associated with insulin resistance in skeletal muscle, and exercise training improves lipid metabolism and insulin sensitivity probably by upregulating GLUT4 and downregulating musclin.
DOI: 10.6084/m9.figshare.7941371
title: Differentiating origins of outflow tract ventricular arrhythmias: a comparison of three different electrocardiographic algorithms

description: Our objective is to evaluate the accuracy of three algorithms in differentiating the origins of outflow tract ventricular arrhythmias (OTVAs). This study involved 110 consecutive patients with OTVAs for whom a standard 12-lead surface electrocardiogram (ECG) showed typical left bundle branch block morphology with an inferior axis. All the ECG tracings were retrospectively analyzed using the following three recently published ECG algorithms: 1) the transitional zone (TZ) index, 2) the V2 transition ratio, and 3) V2 R wave duration and R/S wave amplitude indices. Considering all patients, the V2 transition ratio had the highest sensitivity (92.3%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (93.9%). The latter finding had a maximal area under the ROC curve of 0.925. In patients with left ventricular (LV) rotation, the V2 transition ratio had the highest sensitivity (94.1%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (87.5%). The former finding had a maximal area under the ROC curve of 0.892. All three published ECG algorithms are effective in differentiating the origin of OTVAs, while the V2 transition ratio, and the V2 R wave duration and R/S wave amplitude indices are the most sensitive and specific algorithms, respectively. Amongst all of the patients, the V2 R wave duration and R/S wave amplitude algorithm had the maximal area under the ROC curve, but in patients with LV rotation the V2 transition ratio algorithm had the maximum area under the ROC curve.
DOI: 10.6084/m9.figshare.7941374.v1
title: Deficiency of sex hormones does not affect 17-ß-estradiol-induced coronary vasodilation in the isolated rat heart

description: The relaxation of coronary arteries by estrogens in the coronary vascular beds of naive and hypertensive rats has been well described. However, little is known about this action in gonadectomized rats. We investigated the effect of 17-ß-estradiol (E2) in coronary arteries from gonadectomized rats, as well as the contributions of endothelium-derived factors and potassium channels. Eight-week-old female and male Wistar rats weighing 220-300 g were divided into sham-operated and gonadectomized groups (n=9−12 animals per group). The baseline coronary perfusion pressure (CPP) was determined, and the vasoactive effects of 10 μM E2 were assessed by bolus administration before and after endothelium denudation or by perfusion with NG-nitro-L-arginine methyl ester (L-NAME), indomethacin, clotrimazole, L-NAME plus indomethacin, L-NAME plus clotrimazole or tetraethylammonium (TEA). The CPP differed significantly between the female and sham-operated male animals. Gonadectomy reduced the CPP only in female rats. Differences in E2-induced relaxation were observed between the female and male animals, but male castration did not alter this response. For both sexes, the relaxation response to E2 was, at least partly, endothelium-dependent. The response to E2 was reduced only in the sham-operated female rats treated with L-NAME. However, in the presence of indomethacin, clotrimazole, L-NAME plus indomethacin or L-NAME plus clotrimazole, or TEA, the E2 response was significantly reduced in all groups. These results highlight the importance of prostacyclin, endothelium-derived hyperpolarizing factor, and potassium channels in the relaxation response of coronary arteries to E2 in all groups, whereas nitric oxide may have had an important role only in the sham-operated female group.
DOI: 10.6084/m9.figshare.7941380.v1
title: Activation of locus coeruleus heme oxygenase-carbon monoxide pathway promoted an anxiolytic-like effect in rats

description: The heme oxygenase-carbon monoxide pathway has been shown to play an important role in many physiological processes and is capable of altering nociception modulation in the nervous system by stimulating soluble guanylate cyclase (sGC). In the central nervous system, the locus coeruleus (LC) is known to be a region that expresses the heme oxygenase enzyme (HO), which catalyzes the metabolism of heme to carbon monoxide (CO). Additionally, several lines of evidence have suggested that the LC can be involved in the modulation of emotional states such as fear and anxiety. The purpose of this investigation was to evaluate the activation of the heme oxygenase-carbon monoxide pathway in the LC in the modulation of anxiety by using the elevated plus maze test (EPM) and light-dark box test (LDB) in rats. Experiments were performed on adult male Wistar rats weighing 250-300 g (n=182). The results showed that the intra-LC microinjection of heme-lysinate (600 nmol), a substrate for the enzyme HO, increased the number of entries into the open arms and the percentage of time spent in open arms in the elevated plus maze test, indicating a decrease in anxiety. Additionally, in the LDB test, intra-LC administration of heme-lysinate promoted an increase on time spent in the light compartment of the box. The intracerebroventricular microinjection of guanylate cyclase, an sGC inhibitor followed by the intra-LC microinjection of the heme-lysinate blocked the anxiolytic-like reaction on the EPM test and LDB test. It can therefore be concluded that CO in the LC produced by the HO pathway and acting via cGMP plays an anxiolytic-like role in the LC of rats.
DOI: 10.6084/m9.figshare.7941368.v1
title: Exercise improved lipid metabolism and insulin sensitivity in rats fed a high-fat diet by regulating glucose transporter 4 (GLUT4) and musclin expression

description: This study aimed to evaluate the effects of exercise training on triglyceride deposition and the expression of musclin and glucose transporter 4 (GLUT4) in a rat model of insulin resistance. Thirty male Sprague-Dawley rats (8 weeks old, weight 160±10 g) were fed a high-fat diet (40% calories from fat) and randomly divided into high-fat control group and swimming intervention group. Rats fed with standard food served as normal control. We found that 8-week swimming intervention significantly decreased body weight (from 516.23±46.27 to 455.43±32.55 g) and visceral fat content (from 39.36±2.50 to 33.02±2.24 g) but increased insulin sensitivity index of the rats fed with a high-fat diet. Moreover, swimming intervention improved serum levels of TG (from 1.40±0.83 to 0.58±0.26 mmol/L) and free fatty acids (from 837.80±164.25 to 556.38±144.77 μEq/L) as well as muscle triglycerides deposition (from 0.55±0.06 to 0.45±0.02 mmol/g) in rats fed a high-fat diet. Compared with rats fed a standard food, musclin expression was significantly elevated, while GLUT4 expression was decreased in the muscles of rats fed a high-fat diet. In sharp contrast, swimming intervention significantly reduced the expression of musclin and increased the expression of GLUT4 in the muscles of rats fed a high-fat diet. In conclusion, increased musclin expression may be associated with insulin resistance in skeletal muscle, and exercise training improves lipid metabolism and insulin sensitivity probably by upregulating GLUT4 and downregulating musclin.
DOI: 10.6084/m9.figshare.7941356
title: Relationship between Obesity and Coronary Artery Disease Defined by Coronary Computed Tomography Angiography

description: Abstract Background: Although associated with traditional cardiovascular risk factors, it is unclear whether obesity alone is associated with coronary artery disease (CAD). Objective: To investigate the role of obesity as a risk factor for CAD, defined by coronary computed tomography angiography (CCTA). Methods: This study retrospectively included 1,814 patients referred for CCTA in a hospital in São Paulo, from August 2010 to July 2012. CAD was identified by coronary calcium score and presence of coronary stenosis &gt; 50%. Images were analyzed by two specialists, and the coronary findings were compared between obese and non-obese groups. A multivariate analysis model was used to assess obesity as an independent variable for the occurrence of obstructive CAD. Results: Among the study population, mean age was 58.5 +/- 11.5 years, 22.8% were obese (BMI = 30 kg/m2) and 66.3% were male. The prevalence of obstructive CAD was 18.4% in both groups. Obese patients had higher median calcium score compared to non-obese subjects (14.7 vs. 1.4, respectively, p = 0.019). In the multivariate analysis, obesity was not an independent factor for obstructive CAD (coefficient = -0.035, p = 0.102). Conclusion: Although no differences were observed in the prevalence of obstructive CAD between obese and non-obese individuals, coronary calcium scores were significantly in lower the latter group.
DOI: 10.6084/m9.figshare.7941371.v1
title: Differentiating origins of outflow tract ventricular arrhythmias: a comparison of three different electrocardiographic algorithms

description: Our objective is to evaluate the accuracy of three algorithms in differentiating the origins of outflow tract ventricular arrhythmias (OTVAs). This study involved 110 consecutive patients with OTVAs for whom a standard 12-lead surface electrocardiogram (ECG) showed typical left bundle branch block morphology with an inferior axis. All the ECG tracings were retrospectively analyzed using the following three recently published ECG algorithms: 1) the transitional zone (TZ) index, 2) the V2 transition ratio, and 3) V2 R wave duration and R/S wave amplitude indices. Considering all patients, the V2 transition ratio had the highest sensitivity (92.3%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (93.9%). The latter finding had a maximal area under the ROC curve of 0.925. In patients with left ventricular (LV) rotation, the V2 transition ratio had the highest sensitivity (94.1%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (87.5%). The former finding had a maximal area under the ROC curve of 0.892. All three published ECG algorithms are effective in differentiating the origin of OTVAs, while the V2 transition ratio, and the V2 R wave duration and R/S wave amplitude indices are the most sensitive and specific algorithms, respectively. Amongst all of the patients, the V2 R wave duration and R/S wave amplitude algorithm had the maximal area under the ROC curve, but in patients with LV rotation the V2 transition ratio algorithm had the maximum area under the ROC curve.
DOI: 10.6084/m9.figshare.7941353
title: Neuromuscular Electrical Stimulation on Hemodynamic and Respiratory Response in Patients Submitted to Cardiac Surgery: Pilot Randomized Clinical Trial

description: Abstract Background: Neuromuscular electrical stimulation seems to be a promising option to intensify the rehabilitation and improve the exercise capacity of patients in the immediate postoperative period of cardiac surgery. Objective: This study aimed to evaluate the hemodynamic (heart rate, systolic blood pressure, diastolic blood pressure, and mean blood pressure) and respiratory (respiratory rate and oxygen saturation) responses to neuromuscular electrical stimulation in the immediate postoperative period in patients submitted to cardiac surgery and to verify its feasibility and safety. Methods: This is a pilot randomized controlled trial, wherein critical patients in the immediate postoperative period of cardiac surgery were randomly assigned to a control group, using sham neuromuscular electrical stimulation, or an experimental group, submitted to neuromuscular electrical stimulation sessions (FES), for 60 min, with a 50-Hz frequency, 200-µs pulse duration, time on: 3 s, and time off: 9 s. Data distribution was evaluated by the Shapiro-Wilk test. The analysis of variance was used and a p-value &lt; 0.05 was considered significant. Results: Thirty patients were included in the study. The neuromuscular electrical stimulation was applied within the first 23.13 ± 5.24 h after cardiac surgery, and no changes were found regarding the hemodynamic and respiratory variables between the patients who underwent neuromuscular electrical stimulation, and those in the control group. Conclusions: In the present study, neuromuscular electrical stimulation did not promote changes in hemodynamic and respiratory responses of patients in the immediate postoperative period of cardiac surgery.
DOI: 10.6084/m9.figshare.7941356.v1
title: Relationship between Obesity and Coronary Artery Disease Defined by Coronary Computed Tomography Angiography

description: Abstract Background: Although associated with traditional cardiovascular risk factors, it is unclear whether obesity alone is associated with coronary artery disease (CAD). Objective: To investigate the role of obesity as a risk factor for CAD, defined by coronary computed tomography angiography (CCTA). Methods: This study retrospectively included 1,814 patients referred for CCTA in a hospital in São Paulo, from August 2010 to July 2012. CAD was identified by coronary calcium score and presence of coronary stenosis &gt; 50%. Images were analyzed by two specialists, and the coronary findings were compared between obese and non-obese groups. A multivariate analysis model was used to assess obesity as an independent variable for the occurrence of obstructive CAD. Results: Among the study population, mean age was 58.5 +/- 11.5 years, 22.8% were obese (BMI = 30 kg/m2) and 66.3% were male. The prevalence of obstructive CAD was 18.4% in both groups. Obese patients had higher median calcium score compared to non-obese subjects (14.7 vs. 1.4, respectively, p = 0.019). In the multivariate analysis, obesity was not an independent factor for obstructive CAD (coefficient = -0.035, p = 0.102). Conclusion: Although no differences were observed in the prevalence of obstructive CAD between obese and non-obese individuals, coronary calcium scores were significantly in lower the latter group.
DOI: 10.6084/m9.figshare.7941353.v1
title: Neuromuscular Electrical Stimulation on Hemodynamic and Respiratory Response in Patients Submitted to Cardiac Surgery: Pilot Randomized Clinical Trial

description: Abstract Background: Neuromuscular electrical stimulation seems to be a promising option to intensify the rehabilitation and improve the exercise capacity of patients in the immediate postoperative period of cardiac surgery. Objective: This study aimed to evaluate the hemodynamic (heart rate, systolic blood pressure, diastolic blood pressure, and mean blood pressure) and respiratory (respiratory rate and oxygen saturation) responses to neuromuscular electrical stimulation in the immediate postoperative period in patients submitted to cardiac surgery and to verify its feasibility and safety. Methods: This is a pilot randomized controlled trial, wherein critical patients in the immediate postoperative period of cardiac surgery were randomly assigned to a control group, using sham neuromuscular electrical stimulation, or an experimental group, submitted to neuromuscular electrical stimulation sessions (FES), for 60 min, with a 50-Hz frequency, 200-µs pulse duration, time on: 3 s, and time off: 9 s. Data distribution was evaluated by the Shapiro-Wilk test. The analysis of variance was used and a p-value &lt; 0.05 was considered significant. Results: Thirty patients were included in the study. The neuromuscular electrical stimulation was applied within the first 23.13 ± 5.24 h after cardiac surgery, and no changes were found regarding the hemodynamic and respiratory variables between the patients who underwent neuromuscular electrical stimulation, and those in the control group. Conclusions: In the present study, neuromuscular electrical stimulation did not promote changes in hemodynamic and respiratory responses of patients in the immediate postoperative period of cardiac surgery.
DOI: 10.6084/m9.figshare.7941335
title: Cardiovascular assessment in Female Spotted Paca ( Cuniculus paca )

description: ABSTRACT Aiming to provide cardiovascular morphophysiology information on the Cuniculus paca, an important neotropical rodent, eight healthy adult females of this species were evaluated three times by echocardiography under general anesthesia with isoflurane every 15 days. The exams were performed by a single experienced evaluator with the animals positioned in right and left decubitus. Posteriorly, two expert evaluators measured the cardiac chambers, walls and flow patterns, by B-mode, M-mode, and Doppler ultrasonography. The resulting values were compared among evaluators and periods by the Bland-Altman agreement test and several descriptive statistics were presented for each parameter. Echocardiographic images were obtained between the second and fifth left and right intercostal spaces, enabling the measurement of heart chambers and walls, mitral, tricuspid, aortic and pulmonary valves blood flows, and the ejection and shortening fractions calculation. None of the studied variables showed inter-observers or inter-periods variations. This study provided some normal echocardiographic variables, applicable to epidemiological, pathophysiological or case studies in the Cuniculus paca and phylogenetically close species.
DOI: 10.6084/m9.figshare.7941332
title: Hormonal therapy with estradiol and drospirenone improves endothelium-dependent vasodilation in the coronary bed of ovariectomized spontaneously hypertensive rats

description: Drospirenone (DRSP) is a progestin with anti-aldosterone properties and it reduces blood pressure in hypertensive women. However, the effects of DRSP on endothelium-dependent coronary vasodilation have not been evaluated. This study investigated the effects of combined therapy with estrogen (E2) and DRSP on endothelium-dependent vasodilation of the coronary bed of ovariectomized (OVX) spontaneously hypertensive rats. Female spontaneously hypertensive rats (n=87) at 12 weeks of age were randomly divided into sham operated (Sham), OVX, OVX treated with E2 (E2), and OVX treated with E2 and DRSP (E2+DRSP) groups. Hemodynamic parameters were directly evaluated by catheter insertion into the femoral artery. Endothelium-dependent vasodilation in response to bradykinin in the coronary arterial bed was assessed using isolated hearts according to a modified Langendorff method. Coronary protein expression of endothelial nitric oxide synthase and estrogen receptor alpha (ER-α) was assessed by Western blotting. Histological slices of coronary arteries were stained with hematoxylin and eosin, and morphometric parameters were analyzed. Oxidative stress was assessed in situ by dihydroethidium fluorescence. Ovariectomy increased systolic blood pressure, which was only prevented by E2+DRSP treatment. Estrogen deficiency caused endothelial dysfunction, which was prevented by both treatments. However, the vasodilator response in the E2+DRSP group was significantly higher at the three highest concentrations compared with the OVX group. Reduced ER-α expression in OVX rats was restored by both treatments. Morphometric parameters and oxidative stress were augmented by OVX and reduced by E2 and E2+DRSP treatments. Hormonal therapy with E2 and DRSP may be an important therapeutic option in the prevention of coronary heart disease in hypertensive post-menopausal women.