Search results for " Axis"
showing 10 items of 188 documents
Blunted cortisol response to stress in patients with eating disorders: Its association to bulimic features
2017
ObjectiveClinical research on cortisol response to stress in patients with eating disorders has provided controversial and even contradictory results. As this might be the consequence of the inclusion in the studies of heterogeneous clinical populations, 3 highly selected samples were studied. MethodsDexamethasone suppression test was performed on 15 restricting anorexia nervosa patients without history of bulimia nervosa (BN), 17 BN patients with normal weight and no history of anorexia nervosa, and 22 healthy controls. Three days later, the Trier Social Stress Test was applied, and 8 saliva samples were collected along the trial for cortisol assessment. ResultsWhen the patients were consi…
Acute psychosocial stress effects on memory performance: Relevance of age and sex.
2018
In recent decades, there has been a growing interest in investigating the effects of chronic and acute stress on cognitive processes, especially memory performance. However, research focusing on acute stress effects has reported contradictory findings, probably due to the many factors that can moderate this relationship. In addition to factors related to the individual, such as sex and age, other factors, such as the type of memory assessed, can play a critical role in the direction of these effects. This review summarizes the main findings of our research group and others about the effects of acute psychosocial stress on memory performance in young and older people of both sexes, taking in…
Cortisol and the aging brain: Hypothalamic-pituitary-adrenal axis and cognitive performance in older people.
2015
One of the greatest achievements in modern society is the increase in life expectancy. This increment is so great that children born after 2011 have a one in three chance of reaching their 100th birthday, and specifically in Europe, a quarter of the population will be over 60 years of age by 2020 (European Commission, 2014). This is an important change in society that is occurring for the first time in human history and producing new challenges that need to be addressed, especially those concerning age-related health problems. In this regard, one of the main aims of new research programs, such as Horizon 2020 in Europe, is to increase the possibilities of keeping older people healthy and in…
Personality and Hypothalamic–Pituitary–Adrenal Axis in Older Men and Women
2020
Personality has been related to health and mortality risk, which has created interest in the biological pathways that could explain this relationship. Although a dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been associated with health outcomes and aging, few studies have explored the association between personality and HPA axis functioning in older adults. In addition, it has been suggested that sex could moderate the relationship between personality and HPA axis functioning. Thus, our aim was to analyze the relationship between the big five personality traits and the diurnal cortisol pattern in older adults, as well as sex differences in this relationship. To do so, 7…
Interoceptive Abilities in Inflammatory Bowel Diseases and Irritable Bowel Syndrome
2020
International audience; Alexithymia is usually described by three main dimensions difficulty identifying feelings (DIF), difficulty describing feelings (DDF), and externally oriented thinking (EOT). The most commonly used questionnaire investigating alexithymia, the Toronto Alexithymia Scale (TAS-20), supports this three-factor structure. One important assumption is that alexithymia severity is associated to vulnerability to somatic diseases, among them gastrointestinal disorders. However, the association between alexithymia and gastrointestinal disorders is not systematic, thus questioning the role of alexithymia as a vulnerability factor for those illnesses. A recent factor analysis sugge…
Search for patterns by combining cosmic-ray energy and arrival directions at the Pierre Auger Observatory
2015
Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with E ≥ 6×1019 eV by analyzing cosmic rays with energies above E ≥ 5×1018 eV arriving within an angular separation of approximately 15∘. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with …
The Effects of Probiotics and Prebiotics on Gastrointestinal and Behavioural Symptoms in Autism Spectrum Disorder
2021
Background: Autism Spectrum Disorders (ASDs) are a group of prevalent neuropsychiatric disorders. They present a complex and unknown etiology, which in most cases includes significant peripheral alterations outside the brain such as in the composition of gut microbiota. Because the gut microbiota is involved in modulating the gut-brain axis, several studies have suggested that the microbiome in the gut can modify metabolites which are able to cross the blood-brain barrier and modulate brain function. Methods: We reviewed the current evidence regarding microbiota alterations in patients with ASD and the effects of the administration of probiotics and prebiotics in these patients, both in te…
Laser-induced anisotropy in terbium-gallium garnet
1998
Ga5O12 crystal when illuminated at the terbium ion resonance, becomes optically uniaxial. The optical axis is found to be along the beam-propagation axis. The origin of this symmetry breakdown is a thermal effect. Our observation of a conoscopic pattern is accounted for by a quadratic stress and refractive index distribution model. By spatial integration of the conoscopic pattern, the laser-induced stress birefringence variation as a function of the incident beam power is determined.
Hormonal and metabolic adaptation to fasting: effects on the hypothalamic-pituitary-ovarianaxis and reproductive performance of rabbit does
2006
To assess the impact of acute caloric shortage on reproduction, rabbit does were either fed ad libitum (control, AL), or fasted for 24 (STF) or 48 h (LTF) before induction of ovulation with GnRH injection. Blood samples were collected during the last 3 h of fasting, and the following 4 h after GnRH injection, when feed was provided again, to measure plasma concentrations of LH, estradiol-17β, leptin, insulin, T3, corticosterone, glucose, and NEFA. Before re-feeding, plasma leptin, insulin, and T3 concentrations were lower (P ≤ 0.01) in both fasted groups than in controls, but then gradually increased following realimentation to match those of controls. During fasting, corticoster…
2015
Notch receptors play an essential role in the regulation of central cellular processes during embryonic and postnatal development. The mammalian genome encodes for four Notch paralogs (Notch 1-4), which are activated by three Delta-like (Dll1/3/4) and two Serrate-like (Jagged1/2) ligands. Further, non-canonical Notch ligands such as EGFL7 have been identified and serve mostly as antagonists of Notch signaling. The Notch pathway prevents neuronal differentiation in the central nervous system by driving neural stem cell maintenance and commitment of neural progenitor cells into the glial lineage. Notch is therefore often implicated in the development of brain tumors, as tumor cells share vari…