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1.
J Exp Anal Behav ; 121(2): 163-174, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37752741

ABSTRACT

Behavioral momentum theory (BMT) provides a theoretical and methodological framework for understanding how differentially maintained operant responding resists disruption. A common way to test operant resistance involves contingencies with suppressive effects, such as extinction or prefeeding. Other contingencies with known suppressive effects, such as response-cost procedures arranged as point-loss or increases in response force, remain untested as disruptive events within the BMT framework. In the present set of three experiments, responding of humans was maintained by point accumulation programmed according to a multiple variable-interval (VI) VI schedule with different reinforcement rates in either of two components. Subsequently, subtracting a point following each response (Experiment 1) or increasing the force required for the response to be registered (Experiments 2 and 3 decreased response rates, but responding was less disrupted in the component associated with the higher reinforcement rate. The point-loss contingency and increased response force similarly affected response rates by suppressing responding and human persistence, replicating previous findings with humans and nonhuman animals when other types of disruptive events (e.g., extinction and prefeeding) were investigated. The present findings moreover extend the generality of the effects of reinforcement rate on persistence, and thus BMT, extending the analysis of resistance to two well-known manipulations used to reduce responding in the experimental analysis of behavior.


Subject(s)
Conditioning, Operant , Extinction, Psychological , Animals , Humans , Reinforcement Schedule , Reinforcement, Psychology , Columbidae
2.
Front Physiol ; 14: 1256440, 2023.
Article in English | MEDLINE | ID: mdl-38074329

ABSTRACT

Fatty acid translocase (FAT/CD36) is a transmembrane glycoprotein belonging to the scavenger class B receptor family and is encoded by the cluster of differentiation 36 (CD36) gene. This receptor has a high affinity for fatty acids and is involved in lipid metabolism. An abundance of FAT/CD36 during exercise occurs in mitochondria and solitary muscles. As such, we aimed to systematically review the evidence for the relationship FAT/CD36 and adipose tissue lipolysis during exercise training. Five electronic databases were selected for literature searches until June 2022: PubMed, Web of Science, Scopus, science direct, and Google Scholar. We combined the different synonyms and used the operators ("AND", "OR", "NOT"): (CD36 gene) OR (CD36 polymorphism) OR (cluster of differentiation 36) OR (FAT/CD36) OR (fatty acid translocase) OR (platelet glycoprotein IV) OR (platelet glycoprotein IIIb) AND (adipose tissue lipolysis) OR (fatty acids) OR (metabolism lipid) OR (adipocytes) AND (physical effort) OR (endurance exercise) OR (high-intensity training). All published cross-sectional, cohort, case-control, and randomized clinical trials investigating CD36 polymorphisms and adipose tissue lipolysis during exercise in subjects (elite and sub-elite athletes, non-athletes, sedentary individuals and diabetics), and using valid methods to measure FAT/CD36 expression and other biomarkers, were considered for inclusion in this review. We initially identified 476 publications according to the inclusion and exclusion criteria, and included 21 studies investigating FAT/CD36 and adipose tissue lipolysis during exercise in our systematic review after examination of titles, abstracts, full texts, and quality assessments using the PEDro scale. There were nine studies with male-only participants, three with female-only participants, and nine studies included both female and male participants. There were 859 participants in the 21 selected studies. Studies were classified as either low quality (n = 3), medium quality (n = 13), and high quality (n = 5). In general, the data suggests an association between FAT/CD36 and adipose tissue lipolysis during exercise training. Improvements in FAT/CD36 were reported during or after exercise in 6 studies, while there were no changes reported in FAT/CD36 in 4 studies. An association between fat oxidation and FAT/CD36 expression during exercise was reported in 7 studies. No agreement was reached in 5 studies on FAT/CD36 content after dietary changes and physical interventions. One study reported that FAT/CD36 protein expression in muscle was higher in women than in men, another reported that training decreased FAT/CD36 protein in insulin-resistant participants, while another study reported no differences in FAT/CD36 in young, trained individuals with type 2 diabetes. Our analysis shows an association between FAT/CD36 expression and exercise. Furthermore, an association between whole-body peak fat oxidation and FAT/CD36 expression during exercise training was demonstrated. Systematic Review Registration: [PROSPERO], identifier [CRD42022342455].

3.
Cogn Affect Behav Neurosci ; 23(6): 1500-1512, 2023 12.
Article in English | MEDLINE | ID: mdl-37821754

ABSTRACT

The reward after-effect of effort expenditure refers to the phenomenon that previous effort investment changes the subjective value of rewards when obtained. However, the neural mechanisms underlying the after-effects of effort exertion are still not fully understood. We investigated the modulation of reward after-effects by effort type (cognitive vs. physical) through the lens of neural dynamics. Thirty-two participants performed a physically or cognitively demanding task during an effort phase and then played a simple gambling game during a subsequent reward phase to earn monetary rewards while their electroencephalogram (EEG) was recorded. We found that previous effort expenditure decreased electrocortical activity during feedback evaluation. Importantly, this effort effect occurred in a domain-general manner during the early stage (as indexed by the reward positivity) but in a domain-specific manner during the later and more elaborative stage (as indexed by the P3 and delta oscillation) of reward evaluation. Additionally, effort expenditure enhanced P3 sensitivity to feedback valence regardless of effort type. Our findings suggest that cognitive and physical effort, although bearing some surface resemblance to each other, may have dissociable neural influences on the reward after-effects.


Subject(s)
Brain , Physical Exertion , Humans , Health Expenditures , Reward , Cognition , Motivation
4.
Cognition ; 240: 105603, 2023 11.
Article in English | MEDLINE | ID: mdl-37647742

ABSTRACT

The willingness to exert effort for reward is essential but comes at the cost of fatigue. Theories suggest fatigue increases after both physical and cognitive exertion, subsequently reducing the motivation to exert effort. Yet a mechanistic understanding of how this happens on a moment-to-moment basis, and whether mechanisms are common to both mental and physical effort, is lacking. In two studies, participants reported momentary (trial-by-trial) ratings of fatigue during an effort-based decision-making task requiring either physical (grip-force) or cognitive (mental arithmetic) effort. Using a novel computational model, we show that fatigue fluctuates from trial-to-trial as a function of exerted effort and predicts subsequent choices. This mechanism was shared across the domains. Selective to the cognitive domain, committing errors also induced momentary increases in feelings of fatigue. These findings provide insight into the computations underlying the influence of effortful exertion on fatigue and motivation, in both physical and cognitive domains.


Subject(s)
Emotions , Motivation , Humans , Reward , Cognition
5.
Front Physiol ; 14: 1206484, 2023.
Article in English | MEDLINE | ID: mdl-37469567

ABSTRACT

The effects of voluntary running on the skeletal muscle of rats with pulmonary arterial hypertension (PAH) were tested in the present study. PAH was induced in rats by a single injection of monocrotaline (MCT, 60 mg/kg). Rats in the sedentary hypertension (HS) group had their tolerance to physical exertion reduced throughout the experiment, while those in the sedentary control (SC), exercise control (EC), exercise hypertension (EH) and median exercise (EM) groups maintained or increased. Despite that, the muscular citrate synthase activity was not different between groups. The survival time was higher in the EH (32 days) than in the SH (28 days) (p = 0.0032). SH and EH groups showed a lower percentage of muscle fiber and a higher percentage of extracellular matrix compared to control groups (p < 0.0001). However, the EM and EH groups presented higher percentage of muscle fiber and lower percentage of extracellular matrix than SH group (p < 0.0001). Regarding muscular gene expression, the SH and EM groups showed a lower expression of PGC1-α (p = 0.0024) and a higher expression of VEGF (p = 0.0033) compared to SC, while PGC1-α was elevated in the EH. No difference between groups was found for the carbonylated protein levels (p > 0.05), while the TNF-α/IL-10 ratio was augmented in the EH (p = 0.0277). In conclusion, voluntary running augments the proportion of fiber and affects the gene expression of inflammatory and mitochondrial biogenesis' markers in the skeletal muscle of rats with MCT-induced PAH, which benefits their survival and tolerance to physical effort.

6.
Cereb Cortex ; 33(15): 9343-9353, 2023 07 24.
Article in English | MEDLINE | ID: mdl-37339888

ABSTRACT

Effort expenditure not only prospectively discounts the reward associated with it but also retrospectively adds the subjective value of reward, which is known as the effort paradox. This study aimed to resolve the effort paradox during reward evaluation through the critical lens of neural dynamics and its potential moderators. In total, 40 participants completed an effort-reward task wherein they exerted varying physical efforts to obtain an opportunity to win monetary rewards by active or passive decision-making. We found that after-effects of physical effort expenditure during reward evaluation unfolded as an effort paradox over time, manifesting itself as an effort discounting effect during the reward positivity (RewP) period but as an effort enhancement effect during the late positive potential (LPP) interval. Then, we found a dynamic balance between the discounting effect and the enhancement effect such that the more effort discounted the RewP at the early stage, the more effort increased the LPP at the late stage. Moreover, we observed that the effort-reward relationship was modulated by perceived control such that it increased the reward sensitivity effect and decreased the effort discounting effect. Together, our findings provide new insights into the neural mechanisms underlying the after-effects of physical effort exertion during reward evaluation.


Subject(s)
Physical Exertion , Reward , Humans , Retrospective Studies
7.
Percept Mot Skills ; 130(4): 1624-1643, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37197987

ABSTRACT

We compared the effects of resistance training (ResisT) to pyramidal and traditional weightlifting sets on men's psychophysiological responses. In a randomized crossover design, 24 resistance-trained males performed drop-set, descending pyramid, and traditional ResisT in the barbell back squat, 45° leg press, and seated knee extension. We assessed participants' rating of perceived exertion (RPE) and feelings of pleasure/displeasure (FPD) at the end of each set and at 10, 15, 20, and 30 minutes post-session. No differences were detected across ResisT Methods in total training volume (p = 0.180). Post hoc comparisons revealed that drop-set training elicited higher RPE (M 8.8 SD 0.7 arbitrary units) and lower FPD (M -1.4 SD 1.5 arbitrary units) values compared to descending pyramid (M Set RPE 8.0 SD 0.9 arbitrary units and M Set FPD 0.4 SD 1.6 arbitrary units) and traditional set (M Set RPE 7.5 SD 1.1 arbitrary units and M Set FPD 1.3 SD 1.2 arbitrary units) schemes (p < 0.05). In addition, drop-set training elicited higher session RPE (M 8.1 SD 0.8 arbitrary units) and lower session FPD (M 0.2 SD 1.4 arbitrary units) values than descending pyramid and traditional ResisT (p < 0.001). Similarly, descending pyramid training elicited higher session RPE (M 6.6 SD 0.9 arbitrary units) and lower session FPD (M 1.2 SD 1.4 arbitrary units) than traditional set (M Session RPE 5.9 SD 0.8 arbitrary units and M Session FPD 1.5 SD 1.2 arbitrary units) training (p = 0.015). No differences were found in the temporality of post-session metrics, suggesting that testing 10 and 15 minutes post-ResisT was sufficient to assess session RPE (p = 0.480) and session FPD (p = 0.855), respectively. In conclusion, even with similar total training volume, drop-set training elicited more pronounced psychophysiological responses than either pyramidal or traditional ResisT in resistance-trained males.


Subject(s)
Physical Exertion , Resistance Training , Male , Humans , Physical Exertion/physiology , Resistance Training/methods , Exercise , Weight Lifting/physiology , Pleasure
8.
Brain Behav Immun ; 111: 169-176, 2023 07.
Article in English | MEDLINE | ID: mdl-37076053

ABSTRACT

Cisplatin is a chemotherapeutic agent that is still commonly used to treat solid tumors. However, it has several toxic side effects due in large part to the mitochondrial damage that it induces. As this mitochondrial damage is likely to result in a decrease in the amount of metabolic energy that is available for behavioral activities, it is not surprising that fatigue develops in cancer patients treated with cisplatin. The present preclinical study was initiated to determine whether the detrimental effects of cisplatin were more pronounced on physical effort requiring a lot of energy versus effort that not only requires less energy but also procures energy in the form of food. For this purpose, mice were either trained to run in a wheel or to work for food in various schedules of food reinforcement before being treated with cisplatin. The experiments were carried out only in male mice as we had already reported that sex differences in cisplatin-induced neurotoxicities are minimal. Cisplatin was administered daily for one cycle of five days, or two cycles separated by a five-day rest. As observed in previous experiments, cisplatin drastically reduced voluntary wheel running. In contrast, when cisplatin was administered to food-restricted mice trained to work for a food reward in a progressive ratio schedule or in a fixed-interval schedule, it tended to increase the number of responses emitted to obtain the food rewards. This increase was not associated with any change in the temporal distribution of responses during the interval between two reinforcements in mice submitted to the fixed interval schedule of food reinforcement. When cisplatin was administered to food-restricted mice trained in an effort-based decision-making task in which they had to choose between working for a grain pellet with little effort and working for a preferred chocolate pellet with more effort, it decreased the total number of responses emitted to obtain food rewards. However, this effect was much less marked than the decrease in wheel running induced by cisplatin. The decrease in the effort invested in the procurement of food rewards was not associated with any change in the relative distribution of effort between low reward and high reward during the time course of the test session. These findings show that cisplatin decreases energy-consuming activities but not energy-procuring activities unless they require a choice between options differing in their cost-benefit ratio. Furthermore, they indicate that the physical dimension of fatigue is more likely to develop in cisplatin-treated individuals than the motivational dimension of fatigue.


Subject(s)
Cisplatin , Motor Activity , Mice , Male , Female , Animals , Cisplatin/pharmacology , Motor Activity/physiology , Reward , Motivation , Fatigue
9.
Pediatr Exerc Sci ; 35(2): 84-91, 2023 05 01.
Article in English | MEDLINE | ID: mdl-35894886

ABSTRACT

BACKGROUND: Sickle cell disease is the most common genetic hemoglobinopathy globally and systemically affects body functioning, decreasing exercise capacity. OBJECTIVE: To assess exercise capacity through the 6-minute walk test (6MWT) and biomarkers in children and adolescents with sickle cell disease. MATERIALS AND METHODS: Cross-sectional study involving 20 children and adolescents from Brazil. Demographic and socioeconomic data were obtained. Baseline measurements included biomarkers (red blood cells, hemoglobin, hematocrit, white blood cells, platelets, reticulocytes, lactate dehydrogenase, creatine phosphokinase, C-reactive protein, interleukin 6, and fetal hemoglobin). The following data were obtained before, during, and after the 6MWT: heart rate, blood pressure, and peripheral oxygen saturation. RESULTS: Eighteen children and adolescents ages 5-14 years old were analyzed, 61.1% boys, 100% black or brown, and 61.1% in primary education, with low household income. The average distance walked in 6MWT was 463.8 (137.7) m, significantly less than the predicted value (P < .001). The distance of 6MWT was associated positively with age (P = .042) and inversely with reticulocyte count (P = .42) and interleukin 6 (P = .00). Age modified the effect of interleukin 6 in younger children (P = .038). CONCLUSION: Our findings suggest increased baseline levels of biomarkers of hemolysis and inflammation impact on 6MWT performance.


Subject(s)
Anemia, Sickle Cell , Exercise Tolerance , Male , Humans , Child , Adolescent , Child, Preschool , Female , Cross-Sectional Studies , Exercise Tolerance/physiology , Interleukin-6 , Walking/physiology , Biomarkers , Exercise Test
10.
Nat Sci Sleep ; 14: 2001-2012, 2022.
Article in English | MEDLINE | ID: mdl-36394069

ABSTRACT

Purpose: Motivation is an important driver of behaviour, and several frameworks distinguish the willingness of individuals to invest cognitive versus physical effort to achieve a goal. One outstanding question is whether sleep loss lowers motivation within specific domains of effort, or has a global effect on motivation across multiple domains. Here, we investigated the effects of sleep restriction on the motivation to invest cognitive or physical effort in return for reward. Materials and Methods: 24 healthy young adults (11 females) completed an effort-based decision-making task over two laboratory sessions - once while sleep restricted (three consecutive nights with a three-hour sleep opportunity), and the other while fully rested (nine-hour sleep opportunity on each night). In an initial reinforcement phase, participants were trained to ceiling performance across six levels of effort on separate cognitively and physically demanding tasks. Then, in the critical decision-making phase, participants revealed their preference for how much cognitive or physical effort they would be willing to invest for reward. Results: Sleep restriction reduced the willingness to exert cognitive effort, but spared motivation in the physical domain. Furthermore, the reduction in cognitive motivation appeared to be a primary motivational deficit, which could not be attributed to differences in reward-likelihood of different levels of effort or the temporal structure of the task. Conclusion: The results suggest that sleep restriction has a selective effect on cognitive over physical motivation, which has significant implications for real-world settings in which individuals must maintain high levels of cognitive motivation in the face of chronic sleep loss.

11.
Medicina (Kaunas) ; 58(11)2022 Nov 12.
Article in English | MEDLINE | ID: mdl-36422172

ABSTRACT

Background and Objectives: Cardiovascular diseases are the main cause of death worldwide, and pulse wave velocity (PWV) is considered a predictor of major adverse cardiovascular events. The study intended to be helpful in finding methods for the preliminary assessment of PWV in primary care units. Materials and Methods: The study group consisted of 36 subjects (considered healthy by their own statement) from the medical field (medicine students and residents) aged between 20 and 30 years: 33.3% males and 66.7% females. Two types of measurements were carried out successively: (a) measurements with the arteriograph and (b) measurements on a treadmill effort testing system, where heart rate (HR) was measured over time as a response to step function physical effort (PE). Results: The study allowed for the highlighting of some limits which, if exceeded, can be associated with high PWV values: (i) if after a moderate PE and a resting time of at least 6 min, the HR is larger than 80 b/min; (ii) if the relaxation time in a PE test of moderate intensity is larger than 1 min; (iii) if the HR measured after the subject is raised from the supine to orthostatic position is larger than 100 b/min, and (iv) if the resting HR is larger than 80 b/min. Conclusions: Steady-state HR correlates with PWV and may be used for the preliminary assessment of PWV.


Subject(s)
Cardiovascular Diseases , Pulse Wave Analysis , Male , Female , Humans , Young Adult , Adult , Pulse Wave Analysis/methods , Heart Rate , Heart , Exercise Test
12.
Curr Res Physiol ; 5: 287-291, 2022.
Article in English | MEDLINE | ID: mdl-35800139

ABSTRACT

Asthma involves an increase in airway resistance even in periods between attacks, which generates changes in thoracoabdominal kinematics. The aim of the present study was to detect these adaptations at rest and after physical effort. Evaluations were performed using optoelectronic plethysmography at rest and immediately after physical effort of moderate intensity. Thirty-two children and adolescents participated in the present study (16 asthma- AG and 16 health controls-CG). After exercise, the AG exhibited a less variability of respiratory variables. The kinematic behavior of thoracoabdominal motion was the inverse of that found in healthy controls. These findings suggest mechanical and physiological adaptations to minimize the possible turbulence of the airflow and reduce the impact of airway resistance during physical exertion. Moreover, these changes are found even at rest and in patients whose asthma is clinically controlled.

13.
Front Nutr ; 9: 890388, 2022.
Article in English | MEDLINE | ID: mdl-35694173

ABSTRACT

Background: There are still no studies of the cardiovascular safety of the isolated use of Citrus aurantium in aerobic submaximal exercise. Objective: To evaluate the effect of C. aurantium supplementation on the recovery of cardiorespiratory and autonomic parameters following a session of submaximal aerobic exercise. Methods: Twelve healthy male adults achieved a crossover, randomized, double-blind, and placebo-controlled trial. C. aurantium (600 mg, p-synephrine at 30% amount [180 mg]) or placebo (600 mg of starch) were ingested 90 min before evaluation in randomized days. We evaluated systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), mean arterial pressure (MAP), heart rate (HR) and, HR variability indexes at Rest and during 60 min of recovery from exercise. Results: Citrus aurantium ingestion accelerated the reduction in SBP after exercise, anticipated the return of vagal modulation of the heart after exercise via the HF (ms2), pNN50 (%), and 2 UV% indices. Moreover, rushed the output of sympathetic modulation after exercise via the 0V% index. No unfavorable cardiovascular effects were achieved for HR, DBP, PP, and MAP parameters. Conclusions: Citrus aurantium was shown to be safe for the cardiovascular and autonomic systems alongside submaximal aerobic exercise in healthy males.

14.
Arch. endocrinol. metab. (Online) ; 66(3): 382-392, June 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1393856

ABSTRACT

ABSTRACT The fundamental objective of military field training exercises (FTX) is to prepare military personnel for real-life operations through simulated scenarios. These training sessions often require extreme physical efforts with prolonged, high-intensity exercises that can be combined with food restrictions and partial, or total, sleep deprivation. Such conditions can compromise an individual's physical performance and cause tissue damage, thus affecting their health. This study aimed to perform a systematic review of the literature to identify studies that measured the changes in hormone levels and biomarkers of cellular injury and oxidative stress resulting from FTX with high levels of energy expenditure combined with food and sleep restrictions. PubMed and the Scopus database were searched for articles that combined physical effort/food restriction/sleep deprivation with military training. The initial database search identified 158 articles that were reduced to 18 after confirmation. Significant reductions were reported in thyroid hormones, T3, T4, and anabolic hormones such as testosterone, insulin and androstenedione. An exception for GH was found, which increased throughout FTX. Less distinct responses to FTX were observed with cortisol, TSH and LH. The presence of biomarkers for cellular damage (myoglobin, TNF, and CRP) and increased immune response activities were also described. The scarcity of information on oxidative stress, analyses of cellular injury and biomarkers of inflammatory responses warrants the future study of these topics, which could be helpful in facilitating the safe and effective physical preparations of the members of the armed forces.

15.
Article in English | MEDLINE | ID: mdl-35289515

ABSTRACT

The fundamental objective of military field training exercises (FTX) is to prepare military personnel for real-life operations through simulated scenarios. These training sessions often require extreme physical efforts with prolonged, high-intensity exercises that can be combined with food restrictions and partial, or total, sleep deprivation. Such conditions can compromise an individual's physical performance and cause tissue damage, thus affecting their health. This study aimed to perform a systematic review of the literature to identify studies that measured the changes in hormone levels and biomarkers of cellular injury and oxidative stress resulting from FTX with high levels of energy expenditure combined with food and sleep restrictions. PubMed and the Scopus database were searched for articles that combined physical effort/food restriction/sleep deprivation with military training. The initial database search identified 158 articles that were reduced to 18 after confirmation. Significant reductions were reported in thyroid hormones, T3, T4, and anabolic hormones such as testosterone, insulin and androstenedione. An exception for GH was found, which increased throughout FTX. Less distinct responses to FTX were observed with cortisol, TSH and LH. The presence of biomarkers for cellular damage (myoglobin, TNF, and CRP) and increased immune response activities were also described. The scarcity of information on oxidative stress, analyses of cellular injury and biomarkers of inflammatory responses warrants the future study of these topics, which could be helpful in facilitating the safe and effective physical preparations of the members of the armed forces.

16.
Molecules ; 27(3)2022 Jan 27.
Article in English | MEDLINE | ID: mdl-35164138

ABSTRACT

BACKGROUND: Excessive oxidative stress is associated with hypertension in professional high-temperature working conditions. Polyphenols exhibit a cardioprotective effect. Hawthorn contains high amounts of flavonoids, though its effect on hypertension protection has yet to be studied. This study aims to investigate this effect of extract of hawthorn (EH) or its combination with vitamin C (Vit. C) in rats induced by working under a hot environment. METHODS: Forty-two male rats were randomly divided into a control group under normal temperature and six treatment groups exposed at 33 ± 1 °C along with 1 h of daily treadmill running. They were orally provided with water, Vit. C (14mg/kg), EH (125, 250, and 500 mg/kg), and EH500 + Vit. C, once a day for four weeks. RESULTS: Both EH and Vit. C alone reduced the systolic and diastolic blood pressure of rats exposed to the heat environment; however, their joint supplementation completely maintained their blood pressure to the normal level throughout the experimental period. No morphological changes were found on the intima of aorta. Moreover, the co-supplementation of EH and Vit. C prevented the changes of heat exposure in inducing oxidative stress markers, such as glutathione peroxidase, catalase, total antioxidant capacity, and nitric oxide; the synergistic action was more effective than either individual treatment of EH and Vit. C. Furthermore, the administration of EH had more potent effects on increasing superoxide dismutase, IL-2, the 70 kilodalton heat shock proteins and high sensitivity C reactive protein, and decreasing serum malondialdehyde and lipofuscin in vascular tissue than those in Vit. C group. CONCLUSIONS: A strong synergistic effect of EH and Vit. C on the prevention of hypertension under heat exposure was established, as they inhibited the oxidative stress state. This study also sets up a novel intervention strategy in animal models for investigation on the early phases of hypertension induced by heat exposure.


Subject(s)
Ascorbic Acid , Crataegus/chemistry , Flavonoids , Heat Stress Disorders/prevention & control , Hypertension/prevention & control , Animals , Ascorbic Acid/chemistry , Ascorbic Acid/pharmacology , Flavonoids/chemistry , Flavonoids/pharmacology , Heat Stress Disorders/metabolism , Heat Stress Disorders/physiopathology , Hypertension/metabolism , Hypertension/physiopathology , Male , Rats , Rats, Sprague-Dawley
17.
J Appl Anim Welf Sci ; 25(4): 427-438, 2022.
Article in English | MEDLINE | ID: mdl-34644517

ABSTRACT

Information on fish preference for environmental conditions can be a useful tool to offer them what they want, an important requirement for welfare purposes. Giving that such an approach deals with psychological states of the fish, we investigated whether psychological stress affects fish preference. In this study, we found that the aversive condition of crossing a white open field did not change individual zebrafish's preference for color background or for plant enrichments, despite a great individual variability of preference response. We conclude that individual preferences for environmental conditions are maintained even following a psychological stressor, and highlight that variability in preference options among individuals raises questions about how to best improve welfare of grouped zebrafish.


Subject(s)
Behavior, Animal , Zebrafish , Animals , Zebrafish/physiology
18.
Soc Cogn Affect Neurosci ; 17(4): 398-407, 2022 04 01.
Article in English | MEDLINE | ID: mdl-34450643

ABSTRACT

Motivation is a hallmark of healthy aging, but the motivation to engage in effortful behavior diminishes with increasing age. Most neurobiological accounts of altered motivation in older adults assume that these deficits are caused by a gradual decline in brain tissue, while some psychological theories posit a switch from gain orientation to loss avoidance in motivational goals. Here, we contribute to reconcile the psychological and neural perspectives by providing evidence that the frontopolar cortex (FPC), a brain region involved in cost-benefit weighting, increasingly underpins effort avoidance rather than engagement with age. Using anodal transcranial direct current stimulation together with effort-reward trade-offs, we find that the FPC's function in effort-based decisions remains focused on cost-benefit calculations but appears to switch from reward-seeking to cost avoidance with increasing age. This is further evidenced by the exploratory, independent analysis of structural brain changes, showing that the relationship between the density of the frontopolar neural tissue and the willingness to exert effort differs in young vs older adults. Our results inform aging-related models of decision-making by providing preliminary evidence that, in addition to cortical thinning, changes in goal orientation need to be considered in order to understand alterations in decision-making over the life span.


Subject(s)
Motivation , Transcranial Direct Current Stimulation , Aged , Aging , Decision Making/physiology , Humans , Reward
19.
World J Pediatr Congenit Heart Surg ; 12(6): 693-699, 2021 11.
Article in English | MEDLINE | ID: mdl-34846970

ABSTRACT

BACKGROUND: Anomalous aortic origin of the right coronary artery is known to be a cause of sudden cardiac death in athletes. There are no specific guidelines concerning treatment strategy in the literature. The aim of this study is to describe and report our experience of direct reimplantation technique in the treatment of this anomaly. METHODS: This was a retrospective single center study of 30 patients who underwent surgery in the congenital heart disease unit of Louis Pradel Heart and Lung Hospital between January 2003 and December 2016. The mean follow-up was seven years (3 months-17 years). RESULTS: Thirty patients underwent surgery. The median age was 17 years (0.2-52 years). There were 24 males. The median weight was 58 kg (3.6-118 kg). Fourteen patients were actively engaged in sports. Twenty-six patients had exertional chest pain or syncope. The median time lapse between diagnosis and intervention was 4.5 months (0.5-179 months). Twenty-seven (90%) patients underwent reimplantation of the anomalous coronary artery without transverse aortotomy, while in 3 (10%) patients transverse aortotomy was used to facilitate reimplantation to avoid tension at the anastomosis. There was no early death; one late death occurred in the third postoperative month. At the last follow-up, all patients had returned to normal physical activity without evidence of ischemia. CONCLUSIONS: Direct reimplantation allows for a complete restoration of the coronary anatomy and enables patients to return to normal physical activity. Our study shows encouraging results using a direct reimplantation technique without aortotomy.


Subject(s)
Coronary Vessel Anomalies , Coronary Vessels , Adolescent , Aorta , Coronary Vessel Anomalies/diagnostic imaging , Coronary Vessel Anomalies/surgery , Humans , Male , Replantation , Retrospective Studies , Treatment Outcome
20.
Med Pr ; 72(5): 569-589, 2021 Nov 19.
Article in Polish | MEDLINE | ID: mdl-34643188

ABSTRACT

Due to the controversy related to the necessity to wear protective masks and the negative perceptions of users, an attempt was made to analyze the available scientific research on the physiological consequences of wearing various types of masks. The literature review includes publications available in the PubMed bibliographic database, describing symptoms and complaints of mask users (e.g., the feeling of discomfort, fatigue, headaches), different physiological reactions depending on the type of mask (surgical masks, masks with an exhalation valve, with air flow, etc.) as well as the influence of air composition, temperature and humidity in the space under the mask. The impact of using the mask on the ability to exercise (maximal effort, moderate effort) and mental work was outlined. The consequences of wearing masks by people in a different physiological state (pregnancy) were discussed. Proposals for the organization of work were also presented in order to minimize the negative consequences for people wearing masks. The analysis of the presented studies shows that, regardless of the type of masks worn, they can intensify the body's reactions to a varying degree, increasing the physiological cost of work and worsening the ability to make both physical and mental effort. In addition, the mask can contribute, among others, to more frequent headaches, symptoms of fatigue or the subjective feeling of discomfort. However, despite these adverse effects, the use of masks is important to protect people against harmful factors in the work and communal environments, and during the current SARS-CoV-2 pandemic, it has become a necessity. The discomfort of wearing a mask can be reduced by taking appropriate breaks. It should be emphasized that the rhythm of work and breaks in wearing the mask should take into account the individual limitations of the employee. Med Pr. 2021;72(5):569-89.


Subject(s)
COVID-19 , Masks , Exercise , Humans , Pandemics , SARS-CoV-2
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