Search results for "physiologic"

Training machine learning models with synthetic data improves the prediction of ventricular origin in outflow tract ventricular arrhythmias

2022

In order to determine the site of origin (SOO) in outflow tract ventricular arrhythmias (OTVAs) before an ablation procedure, several algorithms based on manual identification of electrocardiogram (ECG) features, have been developed. However, the reported accuracy decreases when tested with different datasets. Machine learning algorithms can automatize the process and improve generalization, but their performance is hampered by the lack of large enough OTVA databases. We propose the use of detailed electrophysiological simulations of OTVAs to train a machine learning classification model to predict the ventricular origin of the SOO of ectopic beats. We generated a synthetic database of 12-l…

Validation of the German Version of the Music-Empathizing-Music-Systemizing (MEMS) Inventory (Short Version)

2018

Background: Kreutz et al. (2008) developed the Music-Empathizing-Music-Systemizing (ME-MS) Inventory to extend Baron-Cohen's cognitive style theory to the domain of music. We sought to confirm the ME-MS construct in a German sample and to explore these individual differences in relation to music preferences. Methods: The German adaptation of the MEMS Inventory was achieved by forward and backward translation. A total of 1014 participants (532 male, age: 33.79 ± 11.89 years) completed the 18-item short version of the MEMS Inventory online. Confirmatory factor analysis (CFA) was performed and cut-off values were established to identify individuals who could be classified as ME, Balanced, or M…

The Epigenetics of the Endocannabinoid System

2020

The endocannabinoid system (ES) is a cell-signalling system widely distributed in biological tissues that includes endogenous ligands, receptors, and biosynthetic and hydrolysing machineries. The impairment of the ES has been associated to several pathological conditions like behavioural, neurological, or metabolic disorders and infertility, suggesting that the modulation of this system may be critical for the maintenance of health status and disease treatment. Lifestyle and environmental factors can exert long-term effects on gene expression without any change in the nucleotide sequence of DNA, affecting health maintenance and influencing both disease load and resistance. This potentially …

Competent youth in a "disorderly world": findings from an eighteen-nation study.

2012

Future- and school-related stressors are salient for adolescents from different regions of the world, and they cope with these stressors competently.

2016

Optimism is thought to be beneficial for health, and these effects may be mediated through modifications in psychophysiological stress reactivity. Type 2 diabetes (T2D) is associated with reduced cardiovascular responses to stress and heightened cortisol over the day. This study assessed the relationships between optimism, stress responsivity, and daily cortisol output in people with T2D. A total of 140 participants with T2D were exposed to laboratory stress. Heart rate (HR), systolic (SBP), diastolic blood pressure (DBP), and cortisol were measured throughout the session. Cortisol output over the day was also assessed. Optimism and self-reported health were measured using the revised Life …

Extrapituitary Effects of Corticotropin Releasing Hormone and Thyrotropin Releasing Hormone

1993

Besides their regulation of the pituitary-adrenal and pituitary-thyroidal axis, respectively, the neurohormones CRH and TRH act within the central nervous system to evoke and modulate a number of behavioral and physiological processes. In particular, an increase in the sympathetic nervous system and respiratory activity has been observed. The data communicated in this review article emphasize the role of these neurohormones with regard to the neuroendocrine regulation of the autonomic nervous system, sleep and cognitive performance. Moreover, a possible therapeutic role is suggested by the beneficial effects in patients at risk of hypoventilation-associated disorders.

Elevated cortisol modulates hsp70 and hsp90 gene expression and protein in sea bass head kidney and isolated leukocytes

2012

In fish, interactions between Hsps and cortisol are involved in stress modulated physiological processes including innate immune responses. Cortisol exerts a role in the regulation of Hsps synthesis. Fish head kidney is a lymphomieloid and endocrine organ releasing cortisol, and it is the central organ for immune-endocrine interactions. In sea bass, cortisol intraperitoneal injection and in vitro treatment of head kidney cells show that inducible Hsp70 and Hsp90 are modulated by this hormone. However, an inverse relationship between mRNA expression (real-time PCR) and Hsp70 and Hsp90 protein levels (densitometric band analysis) was found. Time-course assays indicate a cortisol-mediated regu…

Context dependent variation in corticosterone and phenotypic divergence of Rana arvalis populations along an acidification gradient

2022

Background Physiological processes, as immediate responses to the environment, are important mechanisms of phenotypic plasticity and can influence evolution at ecological time scales. In stressful environments, physiological stress responses of individuals are initiated and integrated via the release of hormones, such as corticosterone (CORT). In vertebrates, CORT influences energy metabolism and resource allocation to multiple fitness traits (e.g. growth and morphology) and can be an important mediator of rapid adaptation to environmental stress, such as acidification. The moor frog, Rana arvalis, shows adaptive divergence in larval life-histories and predator defense traits along an acidi…

Screening for Low Energy Availability in Male Athletes: Attempted Validation of LEAM-Q

2022

A questionnaire-based screening tool for male athletes at risk of low energy availability (LEA) could facilitate both research and clinical practice. The present options rely on proxies for LEA such screening tools for disordered eating, exercise dependence, or those validated in female athlete populations. in which the female-specific sections are excluded. To overcome these limitations and support progress in understanding LEA in males, centres in Australia, Norway, Denmark, and Sweden collaborated to develop a screening tool (LEAM-Q) based on clinical investigations of elite and sub-elite male athletes from multiple countries and ethnicities, and a variety of endurance and weight-sensiti…

An evolutionary perspective on stress responses, damage and repair

2022

Variation in stress responses has been investigated in relation to environmental factors, species ecology, life history and fitness. Moreover, mechanistic studies have unravelled molecular mechanisms of how acute and chronic stress responses cause physiological impacts (‘damage’), and how this damage can be repaired. However, it is not yet understood how the fitness effects of damage and repair influence stress response evolution. Here we study the evolution of hormone levels as a function of stressor occurrence, damage and the efficiency of repair. We hypothesise that the evolution of stress responses depends on the fitness consequences of damage and the ability to repair that damage. To o…