Significant Differences In Heart Rate Research Articles

Active warm-up and time-of-day effects on repeated-sprint performance and post-exercise recovery.

This study investigated the effects of both an active warm-up and the time-of-day variation on repeated-sprint performance. A second objective was to compare the post-exercise recovery between theexperimentalconditions. Eleven male participants performed ten maximal cycling sprints (6s each, with a 30-s interval between them) in the morning and late afternoon, either after a warm-up or control condition. The warm-up consisted of cycling for 10min at 50% of the peak aerobic power. Rest measurements of rectal, muscle, and skin temperatures were higher in the afternoon compared to the morning (p < 0.05), with no significant differences in heart rate (p = 0.079) and blood lactate concentration (p = 0.300). Warm-up increased muscle temperature, heart rate, and lactate, and reduced skin temperature (all p < 0.001), though no significant differences were observed for rectal temperature (p = 0.410). The number of revolutions (p = 0.034, ηp2 = 0.375), peak (p = 0.034, ηp2 = 0.375), and mean (p = 0.037, ηp2 = 0.365) power of the first sprint (not the average of ten sprints) were higher in the afternoon compared to the morning, regardless of warm-up. However, beneficial performance effects of warming up were evident for the first (p < 0.001) and the average of ten sprints (p < 0.05), regardless of time of day. More remarkable changes during the 60-min post-exercise were observed for rectal temperature (p = 0.005) and heart rate (p = 0.010) in the afternoon than in the morning. Warming-up and time-of-day effects in enhancing muscular power are independent. Although warm-up ensured further beneficial effects on performance than the time-of-day variation, a faster post-exercise recovery was observed in the late afternoon.

Effects of Glucose Fluctuations on Electrocardiogram Readings and the Development of Ventricular Arrhythmia in Diabetic Rats

Objective: Many studies have shown that blood glucose fluctuations (GFs) are more harmful to patients with diabetes mellitus (DM) than sustained hyperglycemia. However, the effect of GF on electrocardiogram (ECG) parameters and vulnerability to ventricular tachycardia/fibrillation (VT/VF) remains poorly characterized. This study aimed to assess the effect of GF on ECG parameters and induction of VT/VF in streptozotocin (STZ)-induced diabetic Sprague-Dawley rats. Methods: Male Sprague-Dawley rats were injected with STZ and randomly divided into 3 treatment groups: controlled STZ-induced diabetic rats (C-STZ) (n = 10); uncontrolled STZ-induced diabetic rats (U-STZ) (n = 10); and STZ-induced diabetic rats with glucose fluctuations (GF-STZ) (n = 10). After 12 weeks, baseline ECG recordings were taken and a VT/VF test was performed with the administration of caffeine and dobutamine. Hematoxylin &amp; eosin and masson staining were used to evaluate pathological cardiac changes after intervention. Results: No significant difference in heart rate, RR interval, P wave (duration and height), PR segment, PR interval, QRS wave duration, and T wave height was observed among the 3 groups (P &gt; 0.05). Compared with the C-STZ group, the U-STZ and GF-STZ groups both had a longer T wave duration ((62.41 ± 2.38) ms vs. (78.37 ± 4.64) ms and (96.06 ± 4.60) ms, P &lt; 0.05), QT interval ((83.66 ± 2.31) ms vs. (101.75 ± 4.56) ms and (119.14 ± 4.88) ms, P &lt; 0.05), and QTc interval ((77.45 ± 1.36) ms vs. (91.36 ± 3.49) ms and (104.55 ± 3.01) ms, P &lt; 0.05), all of which were longest in the GF-STZ group (P &lt; 0.05). Additionally, the GF-STZ group had the highest VT/VF occurrence and duration and the highest arrhythmia score. Conclusion: This study revealed GF can significantly prolong the QT interval, QTc interval, and T wave duration, as well as increase vulnerability to VT/VF in rats, which may be an important electrophysiological mechanism of GF-related ventricular arrhythmia.

Evidence For Sustained Physiological Adaptation From A Single Exercise Bout At Simulated Altitude

Intermittent exposures to normobaric or hypobaric hypoxia have been used to provide enhancements to oxygen delivery capabilities in athletes and in some patient populations as well as in the pre-acclimatization of individuals. The body is capable of very rapid adjustments to this type of environmental stress. However, it is somewhat unclear if an acute exposure to this type of environmental stress is enough to produce evidence of adaptations. PURPOSE: To examine evidence for physiological adaptation after a single bout of exercise at simulated altitude (Stratosphere Hypobaric Training Chamber) as determined from heart rate (HR), peripheral oxygen saturation (SpO2) and the ratio of hemoglobin O2 (oxygen) saturation in the circulating peripheral blood relative to HR (SpO2/HR) response. METHODS: 11 subjects (6 male, 5 female, age 36.5 ± 12.9 yrs, height 173.6 ± 9.2 cm, weight 75.7 ± 14.5 kg) completed 2 hypobaric chamber visits. During both visits, subjects performed a 30 min bout of exercise on a cycle ergometer at the same simulated altitude (2 km n = 1, 3 km n = 2, 4 km n = 8). Based on subjects previous VO2max test results, the exercise was divided into a light to moderate intensity for the first 15 min (target 50-60% WMax), immediately followed by a higher intensity (target 70-80% WMax) for the second 15 min. There was an average of 10 ± 6 days between each testing visit. Statistical analyses included paired samples t-test (p ≤ 0.05). RESULTS: There were no significant changes in workload (p = 0.28) or SpO2 (p = 0.67) between the two visits. However, there was a significant difference in HR (p < 0.001) and SpO2/HR (p < 0.001). There was an average decrease in HR of 19 bpm (12%) from visit 1 (155 ± 17 bpm) to visit 2 (136 ± 26 bpm), along with a 16% average increase in SpO2/HR from visit 1 (0.55 ± 0.06) to visit 2 (0.64 ± 0.13). The average workload across both intensity levels and altitudes were 97 ± 38 W for Visit 1 and 103 ± 39 W for Visit 2, with an average SpO2 of 84 ± 5% for both visits. CONCLUSION: These findings indicate an adaptive response to a short aerobic exercise bout during simulated altitude exposure that appears to be sustained greater than one week after the initial visit. Whether this is linked to oxygen sensing, neurally mediated or suggests early adjustments in oxygen delivery pathways is unclear, but appear unrelated to age, sex or fitness level.

Effectiveness of low-dose ketamine versus lignocaine pre-treatment to prevent propofol injection pain and hemodynamic instability in adult elective surgical patients at Tikur Anbessa specialized hospital, 2022: A prospective observational cohort study

BackgroundPropofol is the most commonly used general anesthesia induction agent. It has injection pain and hemodynamic changes as a major drawback. These side effects are clinically undesirable because they can cause agitation and hinder the smooth induction of anesthesia. Determining the best method to reduce this effect is paramount important. This study aimed to compare the effectiveness of low dose ketamine versus lignocaine pre-treatment to prevent propofol injection pain and hemodynamic changes among study participants. MethodsAn institutional prospective cohort study was conducted on 82 (n1 = n2 = 41) adult elective surgical patients who took general anesthesia induction by propofol at our hospital from 01-Jan-2022 to30 Mar-2022. A systematic random sampling technique was used to select study participants. The pain was scored using a verbal rating scale and mean arterial pressure, heart rate and oxygen saturation was recorded during induction using a questionnaire. An independent samples t-test or chi-square test were used as appropriate. A P-value of < 0.05 was considered as statistically significant. ResultsTwo groups of 41 (LDK = low dose ketamine = Ld = Lignocaine = 41) patients were studied and the incidence of pain after pre-treatment with Low-dose ketamine (4.9%) group was significantly lower than lignocaine (22%) group (p = 0.023). The mean pain score after pre-treatment with low-dose ketamine group was significantly lower than the lignocaine group (p = 0.024). However, there was no statistically significant difference in heart rate, mean arterial pressure, and oxygen saturation (SpO2) between the groups. Conclusion and recommendationPre-treatment with a low dose of ketamine significantly reduces the incidence of propofol injection pain. We recommend its routine use before propofol injection ,and a multi-center more controlled study.

Effects of serial and acute enteric-coated sodium bicarbonate supplementation on anaerobic performance, physiological profile, and metabolomics in healthy young men.

BackgroundPrevious studies have reported that sodium bicarbonate ingestion may enhance high-intensity exercise performance and cause severe gastrointestinal distress. However, enteric-coated sodium bicarbonate may reduce gastrointestinal symptoms of sodium bicarbonate after oral administration. This remains to be confirmed. This study aimed to verify the effects of serial and acute enteric-coated sodium bicarbonate supplementation on anaerobic performance, physiological profile, and metabolomics in healthy young men.MethodsHealthy young males (n = 12) ingested 0.2 g/kg body mass of enteric-coated sodium bicarbonate (ES) in serial enteric-coated sodium bicarbonate (SES, continuous ES supplementation for 5 days) and acute enteric-coated sodium bicarbonate (AES, acute ES supplementation before exercise) or a placebo (PL) in a randomized crossover design. After each supplement protocol, the participants completed four Wingate anaerobic tests (WAT). The first three Wingate tests (testing anaerobic capacity) were performed with a 5-min passive recovery between each. After the third Wingate test, participants were required to complete a 50-min recovery followed by a fourth WAT test (testing the recovery of anaerobic capacity after 50-min intervals). Blood lactate (BLA), heart rate (HR), and ratings of perceived exertion (RPE) were measured in all conditions during the test, as was the subjective gastrointestinal–symptoms assessment questionnaire (GSAQ). Mean power (MP) and peak power (PP) were recorded after four WATs. Urine samples were collected before the test and 50 min after the 3rd WAT.ResultsSerial enteric-coated sodium bicarbonate supplementation improved anaerobic capacity in the third bout of WATs, as observed based on an increase in mean power (SES vs. PL (613 ± 57 vs. 542 ± 64 W), P = 0.024) and peak power (SES vs. PL (1,071 ± 149 vs. 905 ± 150 W), P = 0.016). Acute ES supplementation did not affect anaerobic capacity. The occurrence of gastrointestinal symptoms after enteric-coated sodium bicarbonate supplementation was minimal and no difference compared to placebo in the current study. In particular, serial enteric-coated sodium bicarbonate supplementation had no gastrointestinal side effects before the test. The AES and SES groups had a trivial effect on blood lactate compared to the PLA group. There was no significant difference in HR and RPE among the three groups. Based on targeted metabolomics analysis, the 50 min after the third WAT, the levels of lactate (P < 0.001), L-Malic acid (P < 0.05), and oxaloacetate (P < 0.05) were significantly higher in the SES group than in the PL group. Compared with the AES group, the levels of lactate and fumarate in the SES group were significantly increased (P < 0.05).ConclusionsOur study indicates that serial enteric-coated sodium bicarbonate supplementation positively improves anaerobic performance among healthy young men. However, acute ingestion of enteric-coated sodium bicarbonate did not improve anaerobic exercise performance. Either with serial or acute supplementation doses, enteric-coated sodium bicarbonate produced fewer gastrointestinal symptoms and no difference compared to placebo, especially with no gastrointestinal side effects after serial supplementation. Serial and acute supplementation of enteric-coated sodium bicarbonate might tend to promote lactate clearance. Furthermore, serial enteric-coated sodium bicarbonate ingestion may cause changes in the metabolism of lactate, L-Malic acid, oxaloacetate, and fumarate 50 min after exercise, which presumably may promote the tricarboxylic acid cycle and lactate clearance.

Effects of 2-Hz and 100-Hz Electroacupuncture Stimulation on Respiratory Function and Heart Rate Variability: A Randomized Crossover Study

Background: Bronchial contraction and dilation is thought to be caused by non-adrenergic non-cholinergic nerves. Objective: To investigate the effects of low-frequency (1-5 Hz) and highfrequency (50-100 Hz) electric acupuncture (EA) stimulation on bronchial dilation. Design: Prospective, single-center study Setting: Teikyo Heisei University Subjects: Seventeen healthy male adults Randomization: We randomly assigned subjects to 2-Hz EA and 100-Hz EA groups in a crossover trial. The washout period was 2 weeks. Intervention: Both groups underwent a respiratory function test, followed by a 5-minute rest, followed a 5-minute rest or EA stimulation, followed by a 5min rest. Heart rate variability was measured at rest, followed by another respiratory function test. Acupuncture was delivered near the cervical ganglia at the level of the sixth cervical vertebra on the left side. EA stimuli were set to 2-Hz or 100-Hz, and stimulation intensity was set to a level where no pain was felt. Main outcome measures: Spirometry (forced vital capacity, forced expiratory volume in 1 s, and maximum respiratory flow), autonomic nerve activity (low-frequency component, high-frequency component, and their ratio), and heart rate variability. Results: Heart rate variability analysis showed significant differences in heart rate between the 2-Hz EA and 100-Hz EA groups. The 2-Hz EA group showed a significant increase in HF.Conclusions: 2-Hz EA stimulation resulted in decreased heart rate and increased HF during stimulation. This may be more effective for regulation of the autonomic nerves of the cardiopulmonary system than 100-Hz EA stimulation. Future studies are required to confirm our findings.

Left Atrial Filling Time Index (LAFTI) Evaluated by 2D Speckle Tracking Echocardiography Predicts Poor Cardiac Prognosis in Patients with Heart Failure.

Left atrial (LA) dysfunction is known to be a more sensitive prognostic marker than left ventricular (LV) dysfunction in patients with heart failure (HF). Persistent LA overload increases LA stiffness which impairs LA relaxation. The aim of this study was to investigate whether LA filling time is associated with clinical outcomes in patients with HF. Two-dimensional speckle tracking echocardiography (2DSTE) was performed at discharge, to measure LA and LV strain in 179 HF patients admitted to our hospital. The LA filling time index (LAFTI) was defined as the time from onset of the R wave to the peak LA systolic strain divided by the R-R interval. All patients were prospectively followed with cardiac events including cardiac death and rehospitalization for HF. There were 64 cardiac events during a median follow-up period of 451 days. There were no significant differences in heart rate, severity of HF at discharge, etiology of HF, severity of mitral regurgitation, or LV global longitudinal strain between the cardiac event group and no cardiac event group. Patients with cardiac events had significantly higher levels of brain natriuretic peptide (BNP), ratio of the E wave to e' (E/e'), left atrial volume index (LAVI), and lower LAFTI than those without. Kaplan-Meier analysis showed that patients with lower LAFTI were associated with higher cardiac event rates. Multivariate Cox hazard analysis showed that LAFTI was independently associated with the cardiac events after adjustment for confounding factors. In conclusion, LAFTI is a feasible predictor for cardiac events in patients with HF.

Examination of the acute heart rate and salivary cortisol response to a single bout of walking in urban and green environments: A pilot study

BackgroundRegular physical activity can help prevent noncommunicable diseases, and improve mental health, quality of life, and well-being. ‘Green exercise’ is physical activity performed in natural settings such as parks and open green spaces. It is important to understand whether green exercise can provide additional physiological benefits over and above those of physical activity in urban environments. This pilot study compared the acute effects of a 30-min walk in a green environment to a 30-min walk in urban streets on adults’ heart rate and salivary cortisol. MethodsUsing a 2 × 2 randomised cross-over design, groups of 2–5 adults completed two experimental sessions involving a randomly assigned walk in an urban or a green environment. Heart rate and salivary cortisol were collected at regular intervals before, during, and in the 1.5 h following the walks and were compared within and between participants. Peak height, reactivity, area under the curve with respect to ground (AUCg) and area under the curve with respect to increase (AUCi), were also calculated for heart rate and cortisol and compared between walking conditions. ResultsThe sample included 20 participants (50 % female, mean =24.4 ± 4.0 years). Changes in heart rate (Condition × Time: F[5.8, 103.8]=1.67, p = 0.140) or cortisol (Condition × Time: F[2.6, 49.5]=0.81, p = 0.482) in response to walking were not statistically significantly different between the urban and green walking conditions. There were also no statistically significant differences in heart rate or salivary cortisol for the peak height of the response, reactivity, or AUCi or AUCg between the urban and green walking conditions. ConclusionOur findings suggest that physical exertion is the main driver of the acute physiological response to walking. Notwithstanding psychological benefits reported elsewhere, the acute physiological response to walking was not influenced by the green compared with the urban environment in the current study. Further research is warranted to understand the longer-term effects of regular green exercise.

Comparison of Fentanyl and Dexmedetomidine in Preventing an Increase in Heart Rate During Intubation Among Patients Undergoing General Anesthesia: A Meta-Analysis.

General anesthesia induction, tracheal intubation, extubation, and laryngoscopy are associated with specific hemodynamic changes. Tracheal intubation and laryngoscopy are related to sympathetic stimulation and lead to hypertension and tachycardia. Recent studies have shown that dexmedetomidine is safe and effective as it does not depress respiratory function. This meta-analysis aims to compare the efficacy of dexmedetomidine and fentanyl in preventing an increase in heart rate (HR) during intubation among patients undergoing general anesthesia. A systematic literature search was done using PubMed, Cochrane Library, and Embase to assess studies comparing the efficacy of dexmedetomidine and fentanyl in preventing an increase in HR during intubation. A meta-analysis was done utilizing a random-effects model, and mean differences of HR were determined between fentanyl and dexmedetomidine at baseline, one minute, five minutes, and 10 minutes of intubation. In this meta-analysis, eight randomized control trials were included, involving 548 patients (274 in the fentanyl group and 274 in the dexmedetomidine group). The findings showed that significant difference of HR was significantly lower in the dexmedetomidine group than the fentanyl group at one minute of intubation (mean difference = -8.46; P-value = 0.003), at five minutes of intubation (mean difference = -7.51; P-value = 0.001), and at 10 minutes of intubation (mean difference = -5.15; P-value = 0.030). In the current meta-analysis, dexmedetomidine was better than fentanyl in preventing tachycardia following endotracheal intubation. HR was significantly lower at one minute, five minutes, and 10 minutes after intubation in the dexmedetomidine group compared to the fentanyl group.

Clinical evaluation of prone position ventilation in the treatment of acute respiratory distress syndrome induced by sepsis.

BACKGROUNDAcute respiratory distress syndrome (ARDS) is an acute, diffuse, inflammatory lung injury. Previous studies have shown prone position ventilation (PPV) to be associated with improvement in oxygenation. However, its role in patients with ARDS caused by sepsis remains unknown. AIMTo analyze the clinical effects of PPV in patients with ARDS caused by sepsis. METHODSOne hundred and two patients with ARDS were identified and divided into a control group (n = 55) and a PPV treatment group (n = 47). Outcomes included oxygenation index, lung compliance (Cst) and platform pressure (Pplat), which were compared between the two groups after ventilation. Other outcomes included heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), left ventricular ejection fraction (LVEF), the length of mechanical ventilation time and intensive care unit (ICU) stay, and levels of C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6) after ventilation. Finally, mortality rate was also compared between the two groups. RESULTSOn the first day after ventilation, the oxygenation index and Cst were higher and Pplat level was lower in the PPV group than in the conventional treatment group (P < 0.05). There were no significant differences in oxygenation index, Cst, and Pplat levels between the two groups on the 2nd, 4th, and 7th day after ventilation (P > 0.05). There were no significant differences in HR, MAP, CVP, LVEF, duration of mechanical ventilation and ICU stay, and the levels of CRP, PCT, and IL-6 between the two groups on the first day after ventilation (all P > 0.05). The mortality rates on days 28 and 90 in the PPV and control groups were 12.77% and 29.09%, and 25.53% and 45.45%, respectively (P < 0.05). CONCLUSIONPPV may improve respiratory mechanics indices and may also have mortality benefit in patients with ARDS caused by sepsis. Finally, PPV was not shown to cause any adverse effects on hemodynamics and inflammation indices.

The effects of acute yoga practice on heart rate and heart rate variability responses to mental stress

ABSTRACT Yoga has been shown to reduce stress and to provide health benefits for a number of stress-related disorders. However, the effects and mechanism of an acute bout of yoga practice on relieving stress remain unclear. The aim of this study was to examine the effect of a single bout of yoga on heart rate (HR) and heart rate variability (HRV) response to and recovery from mental stress. This study was conducted with a randomised, counterbalanced, crossover design. A total of 44 participants (mean age 24.58 ± 3.84) completed two conditions (yoga and video watching (VW)) in a randomly assigned order. After each condition, participants underwent a Stroop task and mental arithmetic task. HR and HRV, measured via electrocardiogram, were recorded and analyzed at rest, during each condition, and during the stress and recovery periods. HR was significantly lower during the yoga condition as compared to that during the VW condition. There was no significant difference in HRV observed between the conditions. During both mental stress and recovery periods, there was no significant difference in HR or HRV responses between the yoga and VW conditions. These findings suggested that an acute bout of yoga practice was not superior to quiet sitting in reducing HR and HRV reactivity to and recovery from mental stress. Future studies may consider investigating individuals with exaggerated cardiovascular reactivity to further examine the potential reactivity-lowering effect of yoga.

Comparison of hemodynamic changes and fetal outcome between normotensive and preeclamptic parturient undergoing elective cesarean section under spinal anesthesia: A prospective observational cohort study

BackgroundMaternal hypotension is a common problem during spinal anesthesia resulting in adverse maternal and fetal outcomes. According to theoretical knowledge, it is more common in severe preeclamptic parturients undergoing cesarean section with spinal anesthesia. ObjectiveTo compare fetomother outcome in normotensive and severe preeclamptic parturients undergoing elective cesarean section under spinal anesthesia. MethodologyA prospective cohort study was conducted from Novembers to May 30, 2019 on 84 ASA II and III pregnant mothers. After preloading with 500 ml–1000ml crystalloids, a 0.5%isobaric bupivacaine of 10 mg–12.5 mg was administered for spinal anesthesia.Vital signs (SBP, DBP, MAP and HR) were recorded every 3 min till 30 min, every 5 min then after. Neonatal Apgar scores at one and 5 min after birth and intraoperative fluids consumption were recorded. Data distribution was checked by Shapiro walk's test. Chi-square test was used to calculate the incidence of hypotension between groups; both paired and unpaired t-tests were also used to calculate the percent fall in blood pressure and heart rate from baselines of each group and intergroup respectively, and P-value less than 0.05 were considered statistical significance. ResultsThe incidence of hypotension (over a period of 30 min after spinal anesthesia) in the preeclamptic patients (31%) was less than that of the healthy parturients (59.5%). There was no statistically significant difference in heart rate of both groups before and after induction of spinal anesthesia. The 5th minute Apgar score recordings were also comparable between the groups. ConclusionThis study showed that the incidence and magnitude of spinal anesthesia-induced hypotension was less in severely preeclamptic parturient than healthy parturient who underwent elective cesarean delivery under spinal anesthesia and fetal outcome was comparable.

MICROVASCULAR AND METABOLIC EFFECTS OF A BALANCED ELECTROLYTE SOLUTION AND HEPARINIZED AUTOLOGOUS BLOOD IN HEMORRHAGIC SHOCK

Aim: To compare the microvascular and metabolic effects of autologous blood and a balanced electrolyte solution (BES) containing acetate and malate in hemorrhagic shock (HS) in rats. Methods. The experiments were carried out on male Wistar rats (n=21) under general anesthesia. Blood (35% of estimated blood volume) was withdrawn for 5 minutes. After 60 minutes of HS the collected blood was retransfused, followed by the infusion of BES in the volume of 50% of the blood loss (HS+AB group); HS+BES group received BES in a triple volume of blood loss; a sham-hemorrhage control. Heart rate (HR), mean arterial pressure (MAP), skin blood flow (M), gases and acid-base state of arterial blood, post-occlusive reactive hyperemia (PORH) in the rat tail, serum levels of biomarkers S100b and NSE were assessed after 24 hours. After euthanasia, a histological examination of the brain, lungs, heart and kidneys was performed. Results. In HS+AB and HS+BES groups, 24-hour mortality did not differ (one animal in each group). MAP in these groups was moderately reduced compared to sham group. There were no significant differences in HR, M, acid-base state, PORH and levels of S100b and NSE between the groups. Histological examination revealed circulatory disorders of varying severity in groups with hemorrhage, with more pronounced damage to the brain and kidneys in HS+BES group. Conclusion. Both autologous blood and BES containing acetate and malate equally restore MAP, skin microcirculation, and acid-base state 24 hours after HS. However, fluid resuscitation with BES alone is associated with brain and kidney damage.

Association between carotid atherosclerosis and brain activation patterns during the Stroop task in older adults: An fNIRS investigation

There is an increasing body of evidence suggesting that vascular disease could contribute to cognitive decline and overt dementia. Of particular interest is atherosclerosis, as it is not only associated with dementia, but could be a potential mechanism through which cardiovascular disease directly impacts brain health. In this work, we evaluated the differences in functional near infrared spectroscopy (fNIRS)-based measures of brain activation, task performance, and the change in central hemodynamics (mean arterial pressure (MAP) and heart rate (HR)) during a Stroop color-word task in individuals with atherosclerosis, defined as bilateral carotid plaques (n = 33) and healthy age-matched controls (n = 33). In the healthy control group, the left prefrontal cortex (LPFC) was the only region showing evidence of activation when comparing the incongruous with the nominal Stroop test. A smaller extent of brain activation was observed in the Plaque group compared with the healthy controls (1) globally, as measured by oxygenated hemoglobin (p = 0.036) and (2) in the LPFC (p = 0.02) and left sensorimotor cortices (LMC)(p = 0.008) as measured by deoxygenated hemoglobin. There were no significant differences in HR, MAP, or task performance (both in terms of the time required to complete the task and number of errors made) between Plaque and control groups. These results suggest that carotid atherosclerosis is associated with altered functional brain activation patterns despite no evidence of impaired performance of the Stroop task or central hemodynamic changes.

Prone Position in Treatment of Hypoxemia in Patients Who Underwent Type A Aortic Dissection Surgery.

Postoperative hypoxemia is a high-risk complication after acute type A aortic dissection (TAAD) surgery. Prone position (PP) is an effective treatment for acute respiratory failure, which may improve the gas exchange of the injured lung and the patient's survival. PP is reported to improve the respiratory condition after cardiac surgery. However, limited data exist on the effect of PP in patients who underwent acute TAAD surgery. We retrospectively analyzed the clinical outcomes of seven patients with severe hypoxemia who underwent PP after acute TAAD surgery. The results of arterial blood gas, chest X-ray, and survival were collected. Seven patients (3 female, mean age 48.3±11.7 years) were recruited in this study. All patients received total arch replacement and frozen elephant trunk implantation procedure. The PaO2 at day 1 after PP was higher than before PP (126.3±49.3 vs. 77.8±15.5 mmHg). The oxygenation index rose sharply from 83.0 (80.0, 87.0) to 188.3±56.5 at day 3 after PP. There was no significant difference in heart rate between before and after PP procedure. Chest X-ray showed the diffuse shadow was significantly improved after PP. All patients responded well to PP, and all patients were discharged except for one patient, who died perioperatively due to multiple organ failure. PP is a safe and feasible option for severe hypoxemia patients after TAAD surgery.

Low-Intensity Resistance Exercise Combined With Blood Flow Restriction is More Conducive to Regulate Blood Pressure and Autonomic Nervous System in Hypertension Patients-Compared With High-Intensity and Low-Intensity Resistance Exercise.

Background: The effect of resistance exercise on the autonomic nervous system of patients with hypertension has not been identified. Objective: To explore a suitable resistance training method for hypertension patients to regulate blood pressure (BP) and autonomic nervous system function. Method: Forty-five hypertension patients aged between 55 and 70 years were randomly equally divided into three groups: the high-intensity resistance exercise (HE) group, the low-intensity resistance exercise combined with blood flow restriction (LE-BFR) group, and the low-intensity resistance exercise (LE) group. All patients performed quadriceps femoris resistance exercise. The exercise intensity of HE, LE-BFR and LE group was 65, 30 and 30% of one repetition maximum (1RM), respectively. The LE-BFR group used pressure cuffs to provide 130% of systolic pressure to the patient’s thighs during resistance exercise. The training program was 20 times/min/set with a 1-min break after each set, and was conducted five sets/day and 3 days/week, lasting for 12 weeks. The heart rate (HR), BP, root-mean-square of difference-value of adjacent RR intervals (RMSSD), low frequency (LF) and high frequency (HF) were evaluated before and after the first training and the last training. Result: Significant differences in HR were observed in both recovery states after the first and last training (p < 0.01). After 12 weeks of training, the recovery speed of HR in the LE-BFR group increased significantly (p < 0.01). The systolic blood pressures in the HE and LE-BFR group were significantly reduced (p < 0.05 and p < 0.01), and the differences among groups were significant (p < 0.01). In the last recovery state, the RMSSD of the LE group was significantly lower than that in the first recovery state (p < 0.01). The LF/HF ratios of the HE and LE groups in the resting and recovery states were increased significantly (all p < 0.01). LF/HF ratios in the LE-BFR group in the resting and recovery state were decreased significantly (both p < 0.01). Conclusion: Compared to HE and LE, LE-BFR could effectively decrease systolic pressure and regulate the autonomic nervous system function in hypertension patients.

A Comparison of Physiological Response to Incremental Testing on Stationary and Dynamic Rowing Ergometers.

The purpose of the current study was to compare responses to graded exercise testing (GXT) on 2 popular commercial rowing ergometers. A cohort of 23 subelite male rowers (age 20 [2]y, height 1.88 [0.06]m, body mass 82.0 [8.8]kg) performed a GXT on both stationary (Concept2 [C2]) and dynamic (RowPerfect3 [RP3]) rowing ergometers. Physiological responses including oxygen consumption (VO2), heart rate (HR), blood lactate concentration (BLa), stroke rate (SR), and minute ventilation (VE) were recorded. BLa data were plotted graphically and anaerobic threshold was identified using the Dmax method. Workload, HR, and VO2 at Dmax were interpolated. Physiological responses at maximal exercise and at Dmax were compared, along with response across a discrete range of submaximal workloads. At maximal exercise, no significant differences in HR, VO2, or BLa were observed (P > .05); however, VEpeak was significantly higher during RP3 tests (T = 2.943, P < .05). No significant differences in HR, VO2, or BLa at Dmax were observed (P > .05). When comparing across submaximal workloads, HR was significantly higher with the RP3 at 2 distinct workloads (210 and 240W; P < .05), while SR was higher during RP3 testing at all workloads (F = 56.7, P < .05). When SR was fixed as a covariate, the effect of ergometer on HR response was not significant. A significant workload by ergometer interaction effect was observed for SR with higher data recorded on the RP3 (F = 3.48, P < .01). Levels of agreement for GXT-derived measures of anaerobic threshold (Dmax) were deemed unacceptable. These results indicate that while some differences in HR and VE response were observed between ergometers, these differences were a result of SR alterations between ergometer type. While no differences in response at Dmax were observed, the poor levels of agreement between ergometers suggests that prescription of GXT-derived threshold for training should ideally be specific to the rowing ergometer upon which the test was performed.

Randomized controlled trial of Tesomet for weight loss in hypothalamic obesity.

Context Hypothalamic injury often leads to rapid, intractable weight gain causing hypothalamic obesity, which is associated with increased risk of cardiovascular and metabolic morbidity and mortality. There are no approved or effective pharmacological treatments for hypothalamic obesity, and conventional lifestyle management remains ineffective.Objective To investigate the safety and efficacy of Tesomet (0.5 mg tesofensine/50 mg metoprolol) in adults with hypothalamic obesity.Methods Twenty-one adults with hypothalamic obesity (16 females) were randomized to Tesomet (0.5 mg/50 mg) or placebo for 24 weeks. Patients also received diet/lifestyle counselling. The primary endpoint was safety; secondary endpoints included measures of body weight, appetite scores, quality of life, and metabolic profile.Results Eighteen patients completed 24 weeks. Consent withdrawal, eligibility, and serious adverse events (SAE) unrelated to treatment resulted in dropouts. One patient experienced a Tesomet-related SAE of exacerbated pre-existing anxiety leading to treatment discontinuation. Tesomet-related adverse events were otherwise mostly mild and included sleep disturbances (Tesomet 50%, placebo 13%), dry mouth (Tesomet 43%, placebo 0%), and headache (Tesomet 36%, placebo 0%). No significant differences in heart rate or blood pressure were observed between groups. Compared to placebo, Tesomet resulted in additional mean (95% CI) weight change of −6.3% ((−11.3; −1.3); P = 0.017), increased the number of patients achieving ≥5% weight loss (Tesomet 8/13, placebo 1/8; P = 0.046), and tended to augment the reduction in waist circumference by 5.7 cm ((−0.1; 11.5); P = 0.054).Conclusion Tesomet was welltolerated, did not affect heart rate or blood pressure, and resulted in significant reductions in body weight compared to placebo in adults with hypothalamic obesity.

Physiological response of dairy goats in tropical climates: A study in Tadukan Raga Village, Deli Serdang Regency, North Sumatra

The physiological response can be an indicator of livestock health status related to the environment. Therefore, the purpose of this study was to determine the physiological response of dairy goats kept in Deli Serdang Regency. A total of 93 PE goats were used and their physiological responses were assessed by measuring rectal temperature, heart, and respiration rate at different ages, body weights, and pregnancy statuses. Subsequently, statistical analysis of the data obtained was carried out with T-Test using SPSS version 21.0. The results indicated that there was no significant difference (P>0.05) in goat rectal temperature (39.0, 39.0, 38.9, and 39.0, respectively). Similarly, heart and respiration rates at various ages did not show a significant difference (P>0.05). The body weights (20-29, 30-39, and 40-50kg) did not show significant differences in heart rate (P>0.05) at 72, 69.6, and 73.2 beats/minute. The physiological response of rectal temperature and respiration rate also did not show any difference (P>0.05). There was no significant difference in the respiratory rate of pregnant and non­pregnant goats (p>0.05), which were 42.9 and 42.9 breaths/minute, respectively. It was concluded that dairy goats in Tandukan Raga Village, Deli Serdang Regency did not show different physiological responses such as rectal temperature, heart and respiration rate despite differences in age, weight, and pregnancy status.

Acute Changes in Heart Rate Variability to Glucose and Fructose Supplementation in Healthy Individuals: A Double-Blind Randomized Crossover Placebo-Controlled Trial.

Simple SummaryIn this study, we investigated the cardio-autonomic stress responses to the ingestion of liquid glucose, fructose, a combination thereof and a placebo in healthy individuals at rest. The cardio-autonomic response was more pronounced in all groups with carbohydrates compared to placebo indicating an increased cardio-autonomic stress response resulting in a reduced heart-rate variability. When investigating different levels of blood glucose, the findings showed a significant decline in heart-rate variability with increasing blood glucose levels. This was also seen with severely low levels of blood glucose. The speed of how quick blood glucose increased and decreased also impacted the cardio-autonomic response which further deteriorated heart-rate variability. These findings indicate that healthy human’s autonomic system responds quickly to changes in their blood glucose.Background: It is unknown how different types of carbohydrates alter the cardio-autonomic system in healthy individuals. Therefore, the aim of this study was to investigate how heart-rate variability changes to single dose ingestion of glucose, fructose, glucose and fructose, and an artificial sweetener (sucralose). Methods: In a double-blind randomized crossover placebo-controlled setting, 15 participants received all study-specific substances in liquid form. During each 2-h visit, venous blood glucose was measured in a 5-min interval while heart-rate variability was measured continuously via Holter-electrocardiograph. Results: Ingestion of different types of carbohydrates and sucralose showed significant differences for heart rate (p < 0.001), SDNN (p < 0.008), RMSSD (p < 0.001), pNN50 (p < 0.001) and blood pressure (p < 0.001). Different glucose levels significantly altered parameters of heart-rate variability and blood pressure (all p < 0.001), while the rate of change in blood glucose led to changes in heart rate variability, but not in heart rate (p = 0.25) or blood pressure (p = 0.99). Conclusions: Ingestion of different types of carbohydrates lead to reductions in heart-rate variability compared to a placebo. Blood glucose values above or below 70–90 mg/dL decreased heart rate variability while this was also seen for rapid glucose changes, yet not as pronounced. Healthy individuals should be conscious about carbohydrate intake while maintaining blood glucose levels between 70–90 mg/dL.