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排序方式: 共有1644条查询结果,搜索用时 46 毫秒
61.
Letizia Galasso Angela Montaruli Antonino Mulè Lucia Castelli Eleonora Bruno Andrea Caumo 《Chronobiology international》2013,30(10):1311-1315
ABSTRACTWe have recently shown that rest-activity circadian rhythm significantly differed in women with Binge Eating Disorder (BED) compared to the Ctrl group. In details, patients with BED exhibited significantly reduced levels of MESOR and Amplitude with respect to the Ctrl group. In addition, in this previous study, the results of the actigraphic sleep monitoring provided no evidence of differences in sleep parameters between the two groups. We expanded the original sample obtaining a total of 28 volunteered women, 14 BED women, and 14 Ctrl. We recorded in all 28 participants a 5-day actigraphic monitoring to detect the rhythmometric parameters, interdaily stability, intradaily variability, L5, M10, and sleep parameters. During the study, BED’s women group kept an individual multidisciplinary therapy lasting five weekly days, from Monday to Friday, consisting in cognitive-behavioral therapy and nutritional program, administered in outpatient care from 8:00 a.m. at 5:00 p.m. The combination of both our previous and current study supports the conclusion that the sleep quality of the BED group is significantly better compared to Ctrl. The non-parametric indexes showed how interdaily stability, significantly correlated to sleep efficiency, was higher in BED group compared to the Ctrl group, indicating a better synchronization of rest-activity circadian rhythm. In conclusion, the maintenance of a regular lifestyle, such as imposed by the multidisciplinary therapy, is important to avoid alterations in the sleep-wake cycle, particularly in patients with eating disorders. 相似文献
62.
《Chronobiology international》2013,30(9):1101-1107
Bipolar disorder (BD) has a multifactorial etiology with heterogeneous clinical presentations. Around 25% of BD patients may present with a depressive seasonal pattern (SP). However, there are limited scientific data on the prevalence of SP, its clinical manifestations, and any gender influence. Four hundred and fifty-two BD I and II cases (62% female), recruited from three French university-affiliated psychiatric departments, were assessed for SP. Clinical, treatment, and sociodemographic variables were obtained from structured interviews. One hundred and two (23%) cases met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) criteria for SP, with similar frequency according to gender. Multivariate analysis showed a significant association between SP and BD II (odds ratio [OR]?=?1.99, p?=?0.01), lifetime history of rapid cycling (OR?=?2.05, p?=?0.02), eating disorders (OR?=?2.94, p?=?0.003), and total number of depressive episodes (OR?=?1.13, p?=?0.002). Seventy-one percent of cases were correctly classified by this analysis. However, when stratifying the analyses by gender, SP was associated with BD II subtype (OR?=?2.89, p?=?0.017) and total number of depressive episodes (OR?=?1.21, p?=?0.0018) in males but with rapid cycling (OR?=?3.02, p?=?0.0027) and eating disorders (OR?=?2.60, p?=?0.016) in females. This is the first study to identify different associations between SP and clinical characteristics of BD according to gender. The authors suggest that SP represents a potentially important specifier of BD. These findings indicate that seasonality may reflect increased severity or complexity of disorder. 相似文献
63.
Stephen F. Smagula Caitlin M. DuPont Megan A. Miller Robert T. Krafty Brant P. Hasler Peter L. Franzen 《Chronobiology international》2013,30(11):1553-1559
ABSTRACTIdentifying objectively measurable seasonal changes in 24-h activity patterns (rest-activity rhythms or RARs) that occur in seasonal affective disorder (SAD) could help guide research and practice towards new monitoring tools or prevention targets. We quantified RARs from actigraphy data using non-parametric and extended cosine based approaches, then compared RARs between people with SAD and healthy controls in the summer (n = 70) and winter seasons (n = 84). We also characterized the within-person seasonal RAR changes that occurred in the SAD (n = 19) and control (n = 26) participants who contributed repeated measures. Only controls had significant winter increases in RAR fragmentation (intra-daily variability; in controls mean winter-summer changes (log scale) = 0.05, 0.21 standard deviation, p = 0.03). In SAD participants only, estimated evening settling times (down-mesor) were an average of 30 min earlier in the winter compared with the summer (1-h standard deviation, p = 0.045). These RAR characteristics correlated with greater fatigue (Spearman r = 0.36) but not depression symptom severity. Additional research is needed to ascertain why healthy controls, but not people with SAD, appear to have increased RAR fragmentation in the winter. People with SAD lacked this increase in RAR fragmentation, and instead had earlier evening setting in the winter. Prospective and intervention studies with greater temporal resolution are warranted to ascertain how these seasonal behavioral differences relate to fatigue pathophysiology in SAD. Future research is needed to determine whether extending the winter active period, even in relatively fragmented bouts, could help reduce the fatigue symptoms common in SAD. 相似文献
64.
Laurynas Jokubauskas Aušra Baltrušaitytė Gaivilė Pileičikienė Gediminas Žekonis 《Chronobiology international》2013,30(11):1558-1569
ABSTRACTThis study investigates the recently hypothesized association between distinct circadian manifestations of possible bruxism in subjects with different chronotype profiles, social jetlag and levels of perceived stress. A cross-sectional study was performed by surveying dental students’ of Lithuanian University of Health Sciences. A survey instrument was designed and pilot tested for reliability and validity prior to full-scale administration. The instrument consisted of four sections: socio-demographic questions, bruxism-related items, the Perceived Stress Scale and the Munich ChronoType Questionnaire. The study included 228 students (82.5% females; mean age 22.67 ± 2.27). Awake grinding was significantly associated with later chronotype values (p = 0,039). Despite the lack of significance, binary regression models demonstrated that students with later chronotypes report higher rates of possible bruxism, especially as far as awake grinding (p = .170; OR = 1.89) and sleep grinding (p = .140; OR = 1.60) are concerned. There were no significant associations between perceived stress, social jetlag and bruxism. The scores of perceived stress did not correlate with chronotype values, although a high positive correlation was found between chronotype and social jetlag (r = 0.516, p = .000). It can be concluded that later chronotypes increase the odds for self-reported bruxism, and are significantly associated with higher rates of awake grinding and social jetlag. No interrelationships were found between perceived stress, possible bruxism and social jetlag. 相似文献
65.
《Chronobiology international》2013,30(4):478-485
Bipolar disorder seasonality has been documented previously, though information on the effect of demographic and clinical variables on seasonal patterns is scant. This study examined effects of age, sex, index admission, and predominant polarity on bipolar disorder seasonality in a nationwide population. An inpatient cohort admitted to hospital exclusively for mental illness was derived from the Taiwan National Health Insurance Research Database for 2002–2007. The authors identified 9619 inpatients with bipolar disorder, who had generated 15 078 acute admission records. An empirical mode decomposition method was used to identify seasonal oscillations in bipolar admission data, and regression and cross-correlation analyses were used to quantify the degree and timing of bipolar admission seasonality. Results for seasonality timing found that manic or mixed episodes peak in spring or summer, and depressive episodes peak in winter. Analysis for degree of seasonality revealed that (1) the polarity of patients' index admission predicted the seasonality of relapse admissions; (2) seasonality was significant in female admissions for depressive episodes and in male admissions for manic episodes; (3) young adults displayed a higher degree of seasonality for acute admissions than middle-aged adults; and (4) patients with predominantly depressive admissions displayed a higher degree of seasonality than patients with predominantly manic admissions. Demographic and clinical variables were found to affect the seasonality of acute admissions for bipolar disorders. These findings highlight the need for research on identification and management of seasonal features in bipolar patients. (Author correspondence: ccyang@physionet. org) 相似文献
66.
《Somatosensory & motor research》2013,30(3):77-88
The emergence of barrel cytoarchitecture in mouse somatosensory cortex is extremely well defined. However, mechanisms underlying the development of this cellular organization are not completely understood. While it is generally accepted that hollows emerge via passive displacement of cortical cells by dense thalamocortical afferent clusters in barrel centers, it is not known what causes cellular segregation of barrel sides and septa. Here, we hypothesized that the emergence of sides and septa is related to the progressive asymmetry of dendrites from the cells of the barrel side toward the barrel hollow during development. We tested this hypothesis in the barrel cortex of growth-associated protein-43 heterozygous mice (GAP43 (+/?) mice) that display a 2-day delay in retraction of septally oriented dendrites compared to (+/+) littermates. We predicted that this delayed retraction would result in a subsequent 2-day delay in the emergence of barrel sides and septa. Using cresyl violet staining of barrel cortex, we found that initial emergence of hollows was not different between GAP43 (+/?) mice and (+/+) littermate controls. However, the emergence of sides and septa was delayed by 2 days, supporting our hypothesis that the emergence of barrel sides and septa is related to, and perhaps reliant upon, the developmental step of dendritic orientation toward barrel hollows. This process, which is mechanistically distinct from the emergence of barrel hollows, is likely due to both active and passive events resulting from asymmetric cell orientation. 相似文献
67.
68.
Amanda V. Steckert Samira S. Valvassori Roger B. Varela Francielle Mina Wilson R. Resende Daniela V. Bavaresco Felipe Ornell Felipe Dal-Pizzol João Quevedo 《Neurochemistry international》2013
Several evidences have demonstrated that oxidative stress has a central role in bipolar disorder (BD). Recently, studies have been suggested histone deacetylases (HDAC) as a possible target for new medications in treatment of mood disorders. In this study, we investigated the effects of sodium butyrate (SB, a histone deacetilase inhibitor) on oxidative stress in rats submitted to an animal model of mania induced by d-amphetamine (d-AMPH). Wistar rats were first given d-AMPH or saline (Sal) for 14 days, and then, between days 8 and 14, rats were treated with SB or Sal. Locomotor activity and risk-taking behavior were assessed by open-field test and oxidative stress was measured in prefrontal cortex, amygdala, hippocampus and striatum. The results showed that SB reversed and prevented d-AMPH-induced behavioral effects. The d-AMPH administration induced oxidative damage in all brain structures analyzed. Depending on the cerebral area and technique, SB was able to reverse this impairment. The present study reinforces the need for more studies of HDAC inhibitors as possible target for new medications in treatment for BD. 相似文献
69.
70.
Graziano Di Giuseppe Michele Barbieri Adriana Vallesi Pierangelo Luporini Fernando Dini 《Molecular ecology》2013,22(15):4029-4037
Nuclear (18S and ITS) and mitochondrial (16S) ribosomal RNA gene sequences were determined from genetically distinct wild‐type strains of Antarctic (nine strains), Fuegian (four strains), Greenland (nine strains) and Svalbard (three strains) populations of the marine ciliate, Euplotes nobilii, and analysed for their nucleotide polymorphisms. A close genetic homogeneity was found within and between the Antarctic and Fuegian populations, while more significant levels of genetic differentiation were detected within and between the two Arctic populations, as well as between these populations and the Antarctic/Fuegian ones. The phylogeographical pattern that was derived from these data indicates that gene flow is not limited among Arctic populations; it equally connects the Arctic and Antarctic populations either directly, or through the Fuegian population. This indication reinforces previous evidence from laboratory assays of mating interactions between some of the strains analysed in this work that Southern and Northern polar populations of E. nobilii belong to a unique, panmictic population that substantially share the same gene pool. 相似文献