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1.
Brain Sci ; 14(7)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39061406

RESUMEN

Chemsex is the interplay of substance use by men who have sex with men (MSM) in sexual contexts. The minority stress model and the identity process theory are explanatory models. In this study, we investigated whether (i) differences in certain psychosocial aspects (i.e., shame, aspects of queer identity, and sexual self-concepts) exist between chemsex users and non-users, and (ii) which factors influence an awareness of negative impacts in chemsex users. We conducted an anonymous, cross-sectional, online survey, including sociodemography, sexual history, history of substance use, validated scales for shame-proneness, aspects of queer identity, and sexual self-concepts. Our analysis comprised descriptive statistics, t-tests, Spearman's correlations, and a multiple linear regression model. We recorded a total of 3257 datasets with 107 chemsex users. Chemsex users showed higher rates for risky sexual behavior. Values for shame proneness, more negative aspects of queer identity, and sexual self-concepts were elevated in chemsex users with an awareness of negative impacts. Sexual anxiety, intravenous substance use, and having had a difficult process coming out were significant predictors of feeling negative impacts. Aspects of shame, queer identity aspects, and sexual self-concepts play an important role in the field of chemsex. Different explanatory models seem to be relevant for different subgroups of chemsex users. Chemsex users with an awareness of a problem were particularly vulnerable and distressed but had the highest motivation for change. Prevention, counseling, and care might profit from the inclusion of these aspects. Further anti-stigma campaigns and a specialization of the healthcare system are needed. Registration: DRKS00022336, date: 29th of October, 2020.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38969754

RESUMEN

Chemsex describes the use of specific substances (methamphetamine, GHB/GBL, mephedrone, ketamine) which initiate or enhance sexual experiences and is mainly prevalent among men who have sex with men. Many Chemsex users experience somatic complications (for example sexually transmitted diseases) and sometimes adverse sociological, psychological, and neurological symptoms, such as depression, impulse control disorders or hypersexuality. Changes in impulsivity and deficits in executive functions have demonstrated to be associated with addiction and impulse control disorders as well as frontal brain dysfunction and behavioral control deficits. This study aims to explore the effects of neurophysiological correlates of inhibition and decision making in Chemsex users with an EEG paradigm using event-related potentials (N2, P3). 15 Chemsex users and 14 matched control subjects, all of them men who have sex with man, participated in an auditory Go/NoGo/Voluntary Selection EEG paradigm. In addition, clinical data (e.g. regarding depression), demographic information as well as measures of well-being and sexual behavior were collected. The results demonstrated that clinical symptoms, hypersexuality, and sexual risk behavior were more pronounced in Chemsex users compared to non-users. P3 amplitudes did not differ significantly between groups. However, the Chemsex users showed decreased electrophysiological N2 responses in fronto-central brain regions during decision-making, indicating compromised executive function and inhibitory control. The observed impairments may lead to increased risk behavior regarding drug abuse and hypersexuality. Understanding the neurobiological mechanisms can contribute to targeted interventions in order to mitigate the negative consequences of engaging in Chemsex and improve general well-being.

3.
Front Psychol ; 14: 1264881, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38078262

RESUMEN

Laboratory based sleep deprivation studies demonstrate that lack of sleep impairs well-being and performance ability, but suggest that these effects are mitigated in older adults. Yet, much less is known whether day-to-day variations of sleep have similar consequences in the context of everyday life. This project uses an intensive longitudinal design to investigate the occurrence of day-to-day variations in sleep and their impact on mood and performance in everyday life and to examine whether effects differ between young and older adults. We aim to include 160 young (18-30 years) and 160 older adults (55-75 years) to complete a 21-day experience sampling method (ESM) protocol. During the ESM period, participants are asked to fill in (i) a brief morning questionnaire, (ii) 8 short daytime questionnaires addressing momentary well-being, sleepiness, stress, and mind wandering, followed by a 1 min cognitive task and (iii) a brief evening questionnaire, all delivered via a mobile phone application. Sleep will be measured using self-reports (daily questions) and objectively with wrist actigraphy. The impact of adult age on mean levels and intraindividual variability of sleep will be analyzed using mixed-effects location scale models. The impact of sleep on daily cognitive performance will be analyzed using multilevel linear mixed models. The relationship of sleep to mean values and variability of positive and negative affect in young and older adults will be analyzed using mixed-effects location scale modeling. The overarching purpose of the project is improving the current knowledge on the occurrence of day-to-day variations in sleep and their relationship to performance as well as positive and negative affect in young and older adults.

4.
Brain Sci ; 13(10)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37891794

RESUMEN

BACKGROUND: Reports of poor sleep are widespread, but their link with objective sleep (polysomnography-PSG) is weak in cross-sectional studies. In contrast, the purpose of this study was to investigate the association between changes in subjective and objective sleep variables using data from a study of the reduction in time in bed (TIB). METHODS: One sleep recording was carried out at baseline and one at treatment week 5 (end of treatment) (N = 34). RESULTS: The Karolinska Sleep Quality Index improved and was correlated with improvement in sleep efficiency (r = 0.41, p < 0.05) and reduction in TIB (r = -0.47, p < 0.01) and sleep latency (r = 0.36, p < 0.05). The restorative sleep index showed similar results. Improvements in the insomnia severity index (ISI) essentially lacked correlations with changes in the PSG variables. It was suggested that the latter may be due to the ISI representing a week of subjective sleep experience, of which a single PSG night may not be representative. CONCLUSIONS: It was concluded that changes in the subjective ratings of sleep are relatively well associated with changes in the PSG-based sleep continuity variables when both describe the same sleep.

5.
Sleep Med ; 109: 219-225, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37478658

RESUMEN

Survey studies indicate that reports of disturbed sleep are prevalent and may be prospectively linked to several major diseases. However, it is not clear what self-reported disturbed sleep represents, since the link with objective sleep measures (polysomnography; PSG) seems very weak. The purpose of the present study was to try to investigate what combination of variables (PSG, inflammation, fatigue, anxiety, depression) that would characterize those who complain of disturbed sleep. This has never been done before. Participants were 319 women in a population-based sample, who gave ratings of sleep quality, fatigue, depression, and anxiety, then had their sleep recorded at home, and had blood drawn the following morning for analysis of immune parameters. Correlations and hierarchical multivariable regression analyses were applied to the data. For ratings of difficulties initiating sleep, the associations in the final step were ß = .22, (p < .001) for fatigue, ß = 0.22 (p < .001) for anxiety, and ß = 0.17 (p < .01) for sleep latency, with R2 = 0.14. The rating of repeated awakenings was associated with fatigue (ß = 0.35, p < .001) and C-reactive protein (CRP) (ß = 0.12, p < .05), with R2 = 0.19. The rating of early morning awakenings was associated with fatigue (ß = 0.31, p < .001), total sleep time (TST) (ß = -0.20, p < .01), and CRP (ß = 0.15, p < .05), with R2 = 0.17. Interleukin-6 and Tumour Necrosis Factor were not associated with ratings of sleep problems. The results indicate that subjective fatigue, rather than objective sleep variables, is central in the perception of poor sleep, together with CRP.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos del Sueño-Vigilia , Humanos , Femenino , Polisomnografía/métodos , Depresión/epidemiología , Sueño , Ansiedad/epidemiología , Inflamación , Proteína C-Reactiva , Fatiga/epidemiología , Trastornos del Sueño-Vigilia/epidemiología
6.
Sleep Adv ; 3(1): zpac028, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37193394

RESUMEN

The relationship between sleep duration and sleepiness has seen much research, but no data are available on the association between polysomnographically (PSG) determined total sleep time (TST) (or other PSG variables) and subjective sleepiness during the subsequent day in individuals in their habitual life situation. The purpose of the present study was to study the association between TST and sleep efficiency (SE) (and other PSG variables) and next-day sleepiness at 7 times of the day. A large population-based group of women (N = 400) participated. Daytime sleepiness was measured with the Karolinska Sleepiness Scale (KSS). The association was studied through analysis of variance (ANOVA), as well as regression analyses. For SE there was a significant difference in sleepiness across groups with >90%, 80%-89.99%, and <80% SE (F = 7.2, p < .001, eta2 = 0.04), with lowest sleepiness in the first group. In contrast, TST groups of <6 h, 6-6.99 h, and ≥7 h did not differ significantly. In addition, a pronounced U-shape (eta2 > 0.45) was seen for both analyses, with maximum sleepiness at bedtime (≈ 7.5 KSS units). A multiple regression analysis, including all PSG variables (adjusted for age and BMI), showed that SE was a significant predictor (ß = 0.16, p < .05) of mean sleepiness, even after depression, anxiety, and subjective sleep duration were entered, but this was eliminated by subjective sleep quality. It was concluded that high SE is modestly associated with lower next-day sleepiness in women in a real-life context, but that TST is not.

7.
Nervenarzt ; 93(3): 263-278, 2022 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-33852029

RESUMEN

BACKGROUND: Recently there has been an increase in reports of the phenomenon called chemsex, a subform of sexualized substance use. Chemsex is a neologism consisting of the two terms "chemicals" and "sex". It describes the use of methamphetamine, γ­hydroxybutyrate/γ-butyrolactone (GHB/GBL), mephedrone and sometimes other substances in a sexual context, especially by men who have sex with men (MSM). Chemsex has been described as a significant risk factor for mental and physical diseases. OBJECTIVE: Due to the increasing importance of the phenomenon and the significantly increased number of publications on the subject, this article provides an overview of the current and relevant literature. The aim is to raise awareness on this topic among practitioners and researchers and thus to facilitate access to the help system for those affected. METHOD: A literature search was conducted in PubMed/Medline, Cochrane and Embase for the terms "chemsex", "sexualized drug use" and "slamming. A total of 22 articles were identified as being relevant. RESULTS: In the published literature on chemsex the current focus lies on somatic comorbidities. There is a significantly increased risk of sexually transmitted diseases. Mental illnesses such as depression, substance-induced psychosis and addiction also appear to be a significant consequence of chemsex. An individualized and specialized treatment approach is not yet established. DISCUSSION: The complexity of chemsex with its psychiatric and somatic aspects does not yet appear to be sufficiently reflected by the current data situation; however, due to the mutual influence of these different comorbidities, this patient clientele appears to be particularly at risk in the absence of a specialized treatment option, which is why further research on this topic is needed.


Asunto(s)
Medicina de las Adicciones , Minorías Sexuales y de Género , Enfermedades de Transmisión Sexual , Trastornos Relacionados con Sustancias , Homosexualidad Masculina/psicología , Humanos , Masculino , Conducta Sexual , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/terapia , Trastornos Relacionados con Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/terapia
8.
Front Psychiatry ; 12: 690242, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34135790

RESUMEN

Background: The prevalence of chemsex and sexualized substance use is increasing in several European countries, particularly among men who have sex with men. In this subgroup, illegal substance use is associated with increased sexual risk behavior, which can result in severe physical and psychological impairments. The present study examined the incidence and prevalence of chemsex in German-speaking countries. Methods: To further describe the high-risk group of Chemsex users, participants (N = 429) were asked about their psychotropic substance use, sexual and health-related behavior, health status, and socio-demographic information by using an online questionnaire. Whether Chemsex has negative effects on well-being was measured with the WHO well-being index. Of additional interest was how informed Chemsex users are about the topic and what needs are placed on the practitioners. The online questionnaire consisted of 105 items, and data was collected from March to May 2019. Thousand forty seven datasets were saved with a dropout rate of 59%, 123 completed questionnaires fulfilled the criteria for chemsex users (n =123). Results: There were no significant differences in well-being between chemsex users and non-users. All participants protected themselves against sexually transmitted diseases irregularly or not at all. The majority of chemsex users reported intermittently using illegal substances (ketamine, methamphetamine, mephedrone, γ-butyrolactone/γ-hydroxy butyric acid). They viewed their sexual and substance use behavior as problematic, but few showed motivation for behavior change. Chemsex users clearly expressed a need for more information and advice centers. Conclusion: The results provide information on chemsex users that can be used for the future development of a therapy manual and thus contribute to improving health care for this group. The prevalence of chemsex is increasing and urgently needs more research to protect clients from health impairments and stigmatization.

9.
J Sleep Res ; 30(4): e13236, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33219629

RESUMEN

To learn from feedback (trial and error) is essential for all species. Insufficient sleep has been found to reduce the sensitivity to feedback as well as increase reward sensitivity. To determine whether insufficient sleep alters learning from positive and negative feedback, healthy participants (n = 32, mean age 29.0 years, 18 women) were tested once after normal sleep (8 hr time in bed for 2 nights) and once after 2 nights of sleep restriction (4 hr/night) on a probabilistic selection task where learning behaviour was evaluated in three ways: as generalised learning, short-term win-stay/lose-shift learning strategies, and trial-by-trial learning rate. Sleep restriction did not alter the sensitivity to either positive or negative feedback on generalised learning. Also, short-term win-stay/lose-shift strategies were not affected by sleep restriction. Similarly, results from computational models that assess the trial-by-trial update of stimuli value demonstrated no difference between sleep conditions after the first block. However, a slower learning rate from negative feedback when evaluating all learning blocks was found after sleep restriction. Despite a marked increase in sleepiness and slowed learning rate for negative feedback, sleep restriction did not appear to alter strategies and generalisation of learning from positive or negative feedback.


Asunto(s)
Castigo , Refuerzo en Psicología , Recompensa , Privación de Sueño/fisiopatología , Privación de Sueño/psicología , Adulto , Femenino , Humanos , Masculino , Factores de Tiempo
10.
Sci Rep ; 10(1): 17944, 2020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-33087746

RESUMEN

Sleep deprivation is proposed to inhibit top-down-control in emotion processing, but it is unclear whether sleep deprivation affects emotional mimicry and contagion. Here, we aimed to investigate effects of partial sleep deprivation on emotional contagion and mimicry in young and older humans. Participants underwent partial sleep deprivation (3 h sleep opportunity at the end of night), crossed-over with a full sleep condition in a balanced order, followed by a functional magnetic resonance imaging and electromyography (EMG) experiment with viewing of emotional and neutral faces and ratings of emotional responses. The final sample for main analyses was n = 69 (n = 36 aged 20-30 years, n = 33 aged 65-75 years). Partial sleep deprivation caused decreased activation in fusiform gyri for angry faces and decreased ratings of happiness for all stimuli, but no significant effect on the amygdala. Older participants reported more anger compared to younger participants, but no age differences were seen in brain responses to emotional faces or sensitivity to partial sleep deprivation. No effect of the sleep manipulation was seen on EMG. In conclusion, emotional contagion, but not mimicry, was affected by sleep deprivation. Our results are consistent with the previously reported increased negativity bias after insufficient sleep.The Stockholm sleepy brain study: effects of sleep deprivation on cognitive and emotional processing in young and old. https://clinicaltrials.gov/ct2/show/NCT02000076 .


Asunto(s)
Envejecimiento/psicología , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/fisiología , Cognición/fisiología , Electromiografía , Emociones/fisiología , Cara/fisiología , Imagen por Resonancia Magnética , Privación de Sueño/psicología , Adulto , Factores de Edad , Anciano , Ira/fisiología , Femenino , Felicidad , Humanos , Masculino , Adulto Joven
11.
Nat Sci Sleep ; 12: 289-298, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32547279

RESUMEN

BACKGROUND: Subjectively experienced sleepiness is a problem in society, possibly linked with gray matter (GM) volume. Given a different sleep pattern, aging may affect such associations, possibly due to shrinking brain volume. PURPOSE: The purpose of the present study was to investigate the association between subjectively rated sleepiness and GM volume in thalamus, insula, hippocampus, and orbitofrontal cortex of young and older adults, after a normal night's sleep. METHODS: Eighty-four healthy individuals participated (46 aged 20-30 years, and 38 aged 65-75 years). Morphological brain data were collected in a 3T magnetic resonance imaging (MRI) scanner. Sleepiness was rated multiple times during the imaging sessions. RESULTS: In older, relative to younger, adults, clusters within bilateral mid-anterior insular cortex and right thalamus were negatively associated with sleepiness. Adjustment for the immediately preceding total sleep time eliminated the significant associations. CONCLUSION: Self-rated momentary sleepiness in a monotonous situation appears to be negatively associated with GM volume in clusters within both thalamus and insula in older individuals, and total sleep time seems to play a role in this association. Possibly, this suggests that larger GM volume in these clusters may be protective against sleepiness in older individuals. This notion needs confirmation in further studies.

12.
Chem Commun (Camb) ; 55(87): 13144-13147, 2019 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-31617552

RESUMEN

A homogeneous, redox-neutral photo fragmentation of diol derivatives was developed. Under photo/hydrogen atom transfer (HAT) dual catalysis, diol derivatives such as lignin model compounds and diol monoesters undergo selective ß C(sp3)-O bond cleavage to afford ketones, phenols and acids effectively.

13.
Sci Rep ; 9(1): 8554, 2019 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-31189964

RESUMEN

Several studies suggest that sleep deprivation affects risky decision making. However, most of these are confounded by feedback given after each decision, indicating that decisions may be based on suboptimal feedback-learning rather than risk evaluation. Furthermore, few studies have investigated the effect of sleep loss on aspects of prospect theory, specifically the framing effect and probability distortion. In this within-subjects design, 25 people had (i) two nights of an 8 h sleep opportunity, and (ii) two nights of a 4 h sleep opportunity, in a counter-balanced order. Following the two nights, they performed a gambling task with no immediate feedback; for each round, they could either gamble for a full amount, or take a settlement framed as a gain or a loss for part of the amount. Sleep restriction did not significantly affect the tendency to gamble, the framing effect, or probability distortion, as compared to normal sleep. These results indicate that two nights of sleep restriction affects neither general gambling tendency, nor two of the main predictions of prospect theory. This resilience may be due to a less extreme sleep loss than in previous studies, but also indicates that learning components and risk biases should be separated when assessing the effect of sleep loss on risky behaviour.


Asunto(s)
Juego de Azar , Privación de Sueño , Adolescente , Adulto , Femenino , Juego de Azar/fisiopatología , Juego de Azar/psicología , Humanos , Masculino , Privación de Sueño/fisiopatología , Privación de Sueño/psicología
14.
Front Psychol ; 10: 605, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30967813

RESUMEN

Background: Older adults perform better in tasks which include positive stimuli, referred to as the positivity effect. However, recent research suggests that the positivity effect could be attenuated when additional challenges such as stress or cognitive demands are introduced. Moreover, it is well established that older adults are relatively resilient to many of the adverse effects of sleep deprivation. Our aim was to investigate if the positivity effect in older adults is affected by one night of total sleep deprivation using an emotional working memory task. Methods: A healthy sample of 48 older adults (60-72 years) was either sleep deprived for one night (n = 24) or had a normal night's sleep (n = 24). They performed an emotional working memory n-back (n = 1 and 3) task containing positive, negative and neutral pictures. Results: Performance in terms of accuracy and reaction times was best for positive stimuli and worst for negative stimuli. This positivity effect was not altered by sleep deprivation. Results also showed that, despite significantly increased sleepiness, there was no effect of sleep deprivation on working memory performance. A working memory load × valence interaction on the reaction times revealed that the beneficial effect of positive stimuli was only present in the 1-back condition. Conclusion: While the positivity effect and general working memory abilities in older adults are intact after one night of sleep deprivation, increased cognitive demand attenuates the positivity effect on working memory speed.

15.
R Soc Open Sci ; 6(3): 181704, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31032025

RESUMEN

Sleep restriction has been proposed to cause impaired emotional processing and emotional regulation by inhibiting top-down control from prefrontal cortex to amygdala. Intentional emotional regulation after sleep restriction has, however, never been studied using brain imaging. We aimed here to investigate the effect of partial sleep restriction on emotional regulation through cognitive reappraisal. Forty-seven young (age 20-30) and 33 older (age 65-75) participants (38/23 with complete data and successful sleep intervention) performed a cognitive reappraisal task during fMRI after a night of normal sleep and after restricted sleep (3 h). Emotional downregulation was associated with significantly increased activity in the dorsolateral prefrontal cortex (p FWE < 0.05) and lateral orbital cortex (p FWE < 0.05) in young, but not in older subjects. Sleep restriction was associated with a decrease in self-reported regulation success to negative stimuli (p < 0.01) and a trend towards perceiving all stimuli as less negative (p = 0.07) in young participants. No effects of sleep restriction on brain activity nor connectivity were found in either age group. In conclusion, our data do not support the idea of a prefrontal-amygdala disconnect after sleep restriction, and neural mechanisms underlying behavioural effects on emotional regulation after insufficient sleep require further investigation.

16.
Clin Oral Investig ; 23(10): 3767-3775, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30693401

RESUMEN

OBJECTIVES: The aim of this murine in vivo study was to investigate whether buffy coat-derived putative endothelial progenitor cells (BCEPC) alter tumor growth and neovascularization in oral squamous cell carcinomas (OSCC). MATERIALS AND METHODS: A murine xenograft model using the PCI-13 oral cancer cell line was deployed of which n = 24 animals received 2 × 106 BCEPC by transfusion whereas the control group (n = 24) received NaCl (0.9%) instead. Tumor size, volume, and capillary density were determined by sonography and measurement with a caliper. Immunohistochemical analysis was carried out with antibodies specific for Cytokeratins, Flt-4, Podoplanin, and Vimentin. RESULTS: In the experimental group, systemic application of BCEPC significantly increased tumor volume to 362.49% (p = 0.0012) and weight to 352.38% (p = 0.0018) as well as vascular densities to 162.15% (p = 0.0021) compared with control tumors. In addition, BCEPC-treated xenografts exhibited higher Cytokeratin expression levels by a factor of 1.47 (p = 0.0417), Podoplanin by a factor of 3.3 (p = 0.0020) and Vimentin by a factor of 2.5 (p = 0.0001), respectively. CONCLUSIONS: Immunohistochemical investigations support the notion that BCEPC transfusion influences neovascularization and lymphatic vessel density, thereby possibly promoting tumor progression. Future studies, which will include gene expression analysis, should help to define the possible role of BCEPC during OSCC progression in more detail. CLINICAL RELEVANCE: Endothelial progenitor cells (EPCs) could serve as a target structure for the treatment of OSCC and possibly other solid tumors.


Asunto(s)
Carcinoma de Células Escamosas/patología , Células Progenitoras Endoteliales/citología , Neoplasias de la Boca/patología , Neovascularización Patológica , Animales , Capa Leucocitaria de la Sangre , Femenino , Xenoinjertos , Humanos , Ratones , Ratones Endogámicos NOD , Ratones Desnudos , Ratones SCID , Trasplante Heterólogo
17.
J Sleep Res ; 28(4): e12812, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30609172

RESUMEN

There is a lack of studies on the association between total sleep time (TST) and other polysomnographical parameters. A key question is whether a short sleep is an expression of habitual short sleep, or whether it reflects temporary impairment. The purpose of the present study was to investigate the association between TST and amount of sleep stages and sleep continuity measures, in a large population-based sample of women (n = 385), sleeping at home in a normal daily life setting. The results show that sleep efficiency, N1 (min), N2 (min), REM (min), REM% and proportion of long sleep segments, increased with increasing TST, whereas the number of awakenings/hr, the number of arousals/hr, N1% and REM intensity decreased. In addition, longer sleep was more associated with TST being perceived as of "usual" duration and with better subjective sleep quality. TST was not associated with habitual reported sleep duration. It was concluded that short TST of a recorded sleep in a real-life context may be an indicator of poor objective sleep quality for that particular sleep episode. Because individuals clearly perceived this reduction, it appears that self-reports of poor sleep quality often may be seen as indicators of poor sleep quality. It is also concluded that PSG-recorded sleep duration does not reflect habitual reported sleep duration in the present real-life context.


Asunto(s)
Polisomnografía/métodos , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones
18.
Bioinformatics ; 35(14): 2458-2465, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-30496351

RESUMEN

MOTIVATION: Clinical decision support systems have been applied in numerous fields, ranging from cancer survival toward drug resistance prediction. Nevertheless, clinical decision support systems typically have a caveat: many of them are perceived as black-boxes by non-experts and, unfortunately, the obtained scores cannot usually be interpreted as class probability estimates. In probability-focused medical applications, it is not sufficient to perform well with regards to discrimination and, consequently, various calibration methods have been developed to enable probabilistic interpretation. The aims of this study were (i) to develop a tool for fast and comparative analysis of different calibration methods, (ii) to demonstrate their limitations for the use on clinical data and (iii) to introduce our novel method GUESS. RESULTS: We compared the performances of two different state-of-the-art calibration methods, namely histogram binning and Bayesian Binning in Quantiles, as well as our novel method GUESS on both, simulated and real-world datasets. GUESS demonstrated calibration performance comparable to the state-of-the-art methods and always retained accurate class discrimination. GUESS showed superior calibration performance in small datasets and therefore may be an optimal calibration method for typical clinical datasets. Moreover, we provide a framework (CalibratR) for R, which can be used to identify the most suitable calibration method for novel datasets in a timely and efficient manner. Using calibrated probability estimates instead of original classifier scores will contribute to the acceptance and dissemination of machine learning based classification models in cost-sensitive applications, such as clinical research. AVAILABILITY AND IMPLEMENTATION: GUESS as part of CalibratR can be downloaded at CRAN.


Asunto(s)
Toma de Decisiones Clínicas , Aprendizaje Automático , Teorema de Bayes , Calibración , Probabilidad
19.
J Sleep Res ; 28(4): e12801, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30585371

RESUMEN

Sleep deprivation commonly impairs affective regulation and causes worse mood. However, the majority of previous research concerns young adults. Because susceptibility to sleep deprivation and emotion regulation change distinctively across adult age, we tested here the hypothesis that the effect of sleep deprivation on mood is stronger in young than in older adults. In an experimental design, young (18-30 years) and older adults (60-72 years) participated in either a sleep control (young, n = 63; older, n = 47) or a total sleep deprivation condition (young, n = 61; older, n = 47). Sleepiness, mood and common symptoms of sleep deprivation were measured using established questionnaires and ratings. Sleep-deprived participants felt more sleepy, stressed and cold, and reported lower vigour and positive affect, regardless of age. All the other outcome measures (negative affect, depression, confusion, tension, anger, fatigue, total mood disturbance, hunger, cognitive attenuation, irritability) showed a weaker response to sleep deprivation in the older group, as indicated by age*sleep deprivation interactions (ps < 0.05). The results show that older adults are emotionally less affected by sleep deprivation than young adults. This tolerance was mainly related to an attenuated increase in negative mood. This could possibly be related to the well-known positivity effect, which suggests that older adults prioritize regulating their emotions to optimize well-being. The results also highlight that caution is warranted when generalizing results from sleep deprivation studies across the adult lifespan.


Asunto(s)
Afecto/fisiología , Privación de Sueño/complicaciones , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Privación de Sueño/psicología , Encuestas y Cuestionarios , Adulto Joven
20.
Chem Commun (Camb) ; 55(4): 486-488, 2019 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-30548043

RESUMEN

We describe a photocatalytic method for the cleavage of vicinal diols to aldehydes and ketones. The reaction is catalyzed by blue light and a cerium-catalyst and the scope includes aryl as well as alkyl substituted diols. The simple protocol which works under air and at room temperature enables the valorization of abundant diols.

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