Search results for "Rhythm"
showing 10 items of 822 documents
The COPD multi-dimensional phenotype: A new classification from the STORICO Italian observational study.
2019
BackgroundThis paper is aimed to (i) develop an innovative classification of COPD, multi-dimensional phenotype, based on a multidimensional assessment; (ii) describe the identified multi-dimensional phenotypes.MethodsAn exploratory factor analysis to identify the main classificatory variables and, then, a cluster analysis based on these variables were run to classify the COPD-diagnosed 514 patients enrolled in the STORICO (trial registration number: NCT03105999) study into multi-dimensional phenotypes.ResultsThe circadian rhythm of symptoms and health-related quality of life, but neither comorbidity nor respiratory function, qualified as primary classificatory variables. Five multidimension…
The Retinal Clock Drives the Expression ofKcnv2, a Channel Essential for Visual Function and Cone Survival
2012
PURPOSE The gene Kcnv2 codes for the voltage-gated potassium channel subunit Kv8.2, which can coassemble with Kv2.1 subfamily members to constitute functional voltage-gated potassium channels. Mutations in the Kcnv2 gene result in a retinal disorder designated "cone dystrophy with supernormal rod response (CDSRR)," revealing that Kcnv2 is essential for visual processing and cone survival. The aim of this study was to determine whether expression of Kcnv2 and Kv2.1 is under circadian regulation and may thus contribute to the clock-driven adjustment of photoreceptor function. METHODS Expression of the genes was recorded in preparations of the whole retina and microdissected retinal neurons by…
Retinas of the Diurnal RodentArvicanthis ansorgeiAre Highly Resistant to Experimentally Induced Stress and Degeneration
2011
International audience; PURPOSE. Environmentally induced stress plays a significant role in retinal degeneration and blindness both in animals and in humans. Among such sources of stress, phototoxicity is well studied and has been shown to lead to photoreceptor-specific loss in a number of species. However, the vast majority of studies have been conducted in nocturnal, albino rod-dominant rat and mouse strains, and the pertinence of such findings to human pathology and cone loss is debatable. The authors examined retinal vulnerability to damage in the diurnal murid rodent Arvicanthis ansorgei, a pigmented species with a large number of cones. METHODS. The authors used established protocols …
The moderating role of meaning in life in the relationship between perceived stress and diurnal cortisol.
2018
Previous studies have suggested that meaning in life may buffer the negative effects of stress. This study is the first to investigate the moderating role of meaning in life in the relationship between the perception of stress and diurnal cortisol in two independent samples of healthy adults. In study 1 (n = 172, men = 82, women = 90, age range = 21-55 years, mean age = 37.58 years), the results of moderated regression analyses revealed that there was a significant positive relationship between overall perceived stress in the past month and both diurnal cortisol levels (area-under-the-curve with respect to the ground; AUCg) and the diurnal cortisol slope (DCS) only in individuals with low l…
Recovery of immune control over herpes simplex virus type 1 in female victims of intimate partner violence.
2009
Objectives: To assess the course of immune control over Herpes simplex virus type 1 (HSV-1) through three salivary measures: neutralization of HSV-1, levels of specific antibody against HSV-1 (HSV-1-sIgA) and total immunoglobulin A (total sIgA), and to determine the factors that contribute to its recovery or deterioration. Several studies have demonstrated that intimate partner violence (IPV) affects immune responses in women, but none have investigated the impact longitudinally over time. Methods: Women (n = 60), who participated in our previous cross-sectional study (T-1) and who had been either physically/psychologically (n = 22) or psychologically abused (n = 14) by their partners, were…
Influence of melatonin and serotonin on the number of rat pineal ?synaptic? ribbons and spherules in vitro
1985
Previous studies have shown that the "synaptic" ribbons (SR) and spherules (SS) of the mammalian pineal gland may respond differently under physiological and various experimental conditions. The aim of the present study was to gain insight into the mechanisms that may be responsible for the numerical changes of these organelles during a 24-h cycle. As the possibility exists that the structures are influenced by substances synthesized within the pinealocyte, rat pineal glands were cultured with and without added melatonin or serotonin, using an experimental protocol such that the addition of melatonin and serotonin mimicks the circadian changes of the respective substances within the pineal.…
p-Chlorophenylalanine treatment depresses the number of synaptic ribbon profiles in the rat pineal gland, but does not abolish their day-night rhythm
1995
It is largely unknown as to how the day/night rhythm of pineal synaptic ribbon number is regulated. Transcriptional events related to the nocturnal formation of new synaptic ribbons occur early in the morning, when pineal serotonin levels begin to increase. The present study was carried out in order to elucidate as to how altered serotonin levels affect the day/night changes in the number of synaptic ribbon profiles. To this end, male Sprague-Dawley rats received a single dose of p-chlorophenylalanine (pCPA, 300 mg/kg body weight, 72 hours before sacrifice), which depresses tryptophan hydroxylase activity and hence pineal serotonin levels. Control animals received saline injections. Experim…
Sleep Alterations in Non-demented Older Individuals: The Role of Cortisol
2017
Background: Sleep alterations can impair quality of life and contribute to disease progression but they, and their features and contributing factors, are rarely analysed in institutionalised older individuals. In this study, we investigated sleep alterations, the factors involved, and the role of cortisol in sleep-related problems in institutionalised individuals. Methods: We conducted a descriptive cross-sectional study in participants living in nursing homes in Valencia (Spain); sleep alterations were determined based on two validated tools: the Athens insomnia scale and Oviedo sleep questionnaire. Plasma cortisol was measured in the morning and determined by high performance liquid chrom…
Polysomnographic Findings in Fragile X Syndrome Children with EEG Abnormalities
2019
Fragile X syndrome (FXS) is a genetic syndrome with intellectual disability due to the loss of expression of the FMR1 gene located on chromosome X (Xq27.3). This mutation can suppress the fragile X mental retardation protein (FMRP) with an impact on synaptic functioning and neuronal plasticity. Among associated sign and symptoms of this genetic condition, sleep disturbances have been already described, but few polysomnographic reports in pediatric age have been reported. This multicenter case-control study is aimed at assessing the sleep macrostructure and at analyzing the presence of EEG abnormalities in a cohort of FXS children. We enrolled children with FXS and, as controls, children wit…
Comment on “Sleep disturbances and later cognitive status: a multi-centre study”
2018
To investigate the associations between sleep disturbances in mid-life and late-life and late-life cognitive status.In four population-based studies (three Swedish studies: H70 study, Kungsholmen Project (KP) and The Swedish Panel Study of Living Conditions of the Oldest Old (SWEOLD); and one Finnish study: Cardiovascular Risk Factors, Aging and Dementia (CAIDE)), participants provided self-reports on insomnia, nightmares and general sleep problems. Late-life cognitive status was measured by the Mini Mental State Exam (MMSE). The associations between late-life sleep disturbances and cognition 3-11 years later were investigated across all studies (n = 3210). Mean baseline ages were 70 (CAIDE…