Rôle de diverses caractéristiques des fibres dans la cytotoxicité des poussières minérales in vitro

Nos travaux portent sur les caractéristiques morphologiques et physicochimiques conférant à certaines poussières minérales leur habileté à induire une réponse inflammatoire chronique à l'origine de plusieurs pneumoconioses. Nos résultats démontrent que les fibres d'amiante chrysotile A, chrysotile B, amosite et crocidolite (d'origine naturelle) ainsi que les fibres de verre John's Manville code 100 (d'origine synthétique) ont un potentiel toxique et inflammatoire important envers les macrophages alvéolaires de rats in vitro. La longueur des fibres, plus particulièrement, le nombre de fibres plus longues qu'environ 6 um, serait le facteur le plus important dans la détermination du potentiel toxique et inflammatoire de ces poussières minérales alors que le diamètre des fibres, le nombre de fibres par unité de masse ou les groupements chimiques de surface des fibres ne semblent pas jouer un rôle important dans ce processus

The Natural History of Insomnia: Acute Insomnia and First-onset Depression

Study Objectives: While many studies have examined the association between insomnia and depression, no studies have evaluated these associations 1) within a narrow time frame, 2) with specific reference to acute & chronic insomnia, and 3) using polysomnography. In the present study, the association between insomnia and first-onset depression was evaluated taking into account these considerations. Design: A mixed-model inception design. Setting: Academic research laboratory. Participants: Fifty-four individuals (acute insomnia (n=33), normal sleepers (n=21)) with no reported history of a sleep disorder, chronic medical condition, or psychiatric illness. Interventions: N/A Measurements and Results: Participants were assessed at baseline (two nights of polysomnography and psychometric measures of stress and mood) and insomnia and depression status were reassessed at 3 months. Individuals with acute insomnia exhibited more stress, poorer mood, worse subjective sleep continuity, increased N2 sleep and decreased N3 sleep. Individuals that transitioned to chronic insomnia exhibited (at baseline) shorter REM Latencies and reduced N3 sleep. Individuals that exhibited this pattern, in the transition from acute to chronic insomnia, were also more likely to develop first-onset depression (9.26%) as compared to those who remitted from insomnia (1.85%) or were normal sleepers (1.85%). Conclusion: The transition from acute to chronic insomnia is presaged by baseline differences in sleep architecture that have, in the past, been ascribed to Major Depression, either as heritable traits or as acquired traits from prior episodes of depression. The present findings suggest that the “sleep architecture stigmata” of depression may actually develop over the course transitioning from acute to chronic insomnia

Validation of the Fear of Sleep Inventory (FOSI) in an Urban Young Adult African American Sample

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106083/1/jts21882.pd

Prevalence of Bowel Damage Assessed by Cross-Sectional Imaging in Early Crohn's Disease and its Impact on Disease Outcome

n/

A combined group treatment for nightmares and insomnia in combat veterans: A pilot study

Insomnia and nightmares are hallmarks of posttraumatic stress disorder (PTSD). Sleep disturbances in PTSD negatively impact clinical course and functioning. In this open clinical trial, the preliminary effects of a combined treatment for insomnia and nightmares in combat veterans with PTSD were assessed. Ten combat veterans participated in a 10-session group treatment combining cognitive–behavioral therapy for insomnia with exposure, rescripting, and relaxation therapy. Participants maintained daily sleep and dream diaries and completed self-report measures of sleep quality and PTSD symptoms pre- and posttreatment. Participants reported improvements in sleep and nightmares following treatment. Future research using controlled designs to evaluate this treatment is warranted.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64565/1/20468_ftp.pd

Predictors of improvement in subjective sleep quality reported by older adults following group-based cognitive behavior therapy for sleep maintenance and early morning awakening insomnia

ObjectiveCognitive behavior therapy is an effective nonpharmacologic treatment for insomnia. However, individualized administration is costly and often results in substantial variability in treatment response across individual patients, particularly so for older adults. Group-based administration has demonstrated impressive potential for a brief and inexpensive answer to the effective treatment of insomnia in the older population. It is important to identify potential predictors of response to such a treatment format to guide clinicians when selecting the most suitable treatment for their patients. The aim of our study was to identify factors that predict subjective sleep quality of older adults following group-based administration of cognitive behavior therapy for insomnia (CBT-I).MethodsEighty-six adults (41 men; mean age, 64.10 y; standard deviation [SD], 6.80) with sleep maintenance or early morning awakening insomnia were selected from a community-based sample to participate in a 4-week group-based treatment program of CBT-I. Participants were required to complete 7-day sleep diaries and a comprehensive battery of questionnaires related to sleep quality and daytime functioning. Hierarchical multiple regression analyses were used to identify factors predicting subjective sleep quality immediately following treatment and at 3-month follow-up. Sleep diaries reported average nightly sleep efficiency (SE), which was used as the outcome measure of sleep quality.Results and conclusionsParticipants with the greatest SE following treatment while controlling for pretreatment SE were relatively younger and had more confidence in their ability to sleep at pretreatment. These characteristics may be useful to guide clinicians when considering the use of a group-based CBT-I for sleep maintenance or early morning awakening insomnia in older adults.Nicole Lovato, Leon Lack, Helen Wright, David J. Kennawa

Le FORUM, Vol. 34 No. 4

https://digitalcommons.library.umaine.edu/francoamericain_forum/1028/thumbnail.jp

Insomnia severity as a mediator of the association between mental health symptoms and alcohol use in young adult veterans

PurposePrior research has documented associations between mental health and alcohol use, mental health and insomnia, and insomnia and alcohol use. This study examined insomnia severity as a mediator of the association between mental health and alcohol-related outcomes in young adult veterans.ProceduresVeterans aged 18-34 years (N=622, 83% male) who reported drinking in the past year completed assessments at baseline and one-month follow-up as part of a larger intervention trial. Participants reported symptoms of depression and posttraumatic stress disorder (PTSD) at baseline, insomnia severity at one month, and alcohol use and related consequences at baseline and one month. Mediation analyses using bootstrapped confidence intervals were used to examine the indirect effects of baseline mental health symptoms on alcohol-related outcomes at one month via insomnia severity.Main findingsInsomnia severity was associated with both drinking quantity and alcohol-related consequences. Greater depressive (but not PTSD) symptoms were associated directly with more alcohol-related consequences. Neither depressive nor PTSD symptoms had direct effects on drinking quantity when controlling for the other mental health symptoms (e.g., depressive symptoms did not predict drinking quantity when controlling for symptoms of PTSD). However, symptoms of depression and PTSD predicted drinks per week and alcohol-related consequences indirectly through insomnia severity.ConclusionsSymptoms of depression and PTSD increase risk for alcohol use and related consequences in part by increasing symptoms of insomnia. Findings suggest that insomnia may be an appropriate target for prevention and intervention efforts among heavy-drinking Veterans reporting symptoms of depression or PTSD

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field