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101.
STUDY OBJECTIVES: Chronic primary insomnia has been hypothesized to result from conditioned arousal or the inability to initiate normal sleep processes. The event-related potentials (ERPs) N1, P2, and N350 are useful indexes of arousal. The objective is to compare these ERPs in primary chronic psychophysiological insomniacs (INS) and good sleepers (GS) during multiple recordings. PARTICIPANTS: Participants were 15 INS (mean age = 46 years, SD = 7.5) and 16 GS (mean age = 37 years, SD = 10.1). METHODS AND PROCEDURE: Following a multistep clinical evaluation, INS and GS participants underwent 4 consecutive nights of PSG recordings (N1 to N4). ERPs were recorded on the 3rd and 4th nights in the sleep laboratory (N3 and N4). ERPs recordings were made during wake on both nights (in the evening and upon awakening), with the addition of sleep-onset recordings on N4. Auditory stimuli consisted of "standard" and "deviant" tones. STATISTICAL ANALYSIS: Repeated measures ANOVAs were computed for each ERP for each recording for each type of stimulus. RESULTS: The amplitude of P2 and N350 was greater for the deviant than for the standard stimulus in both groups. The amplitude of N1 was larger in INS than GS in the morning and the evening. While the amplitude of N350 was larger in GS than in INS at sleep onset, the amplitude of P2 was greater in INS than in GS at that time. CONCLUSION: Signs of greater cortical arousal in psychophysiological insomnia individuals are observed, especially upon awakening in the morning. However, at sleep onset, difficulties from disengaging from wake processes and some inability at initiating normal sleep processes appear also present in individuals with insomnia compared to good sleepers.  相似文献   
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OBJECTIVES: Dehydroepiandrosterone (DHEA) is a steroid hormone involved in physiological aging. When administered by oral route, it has been shown to positively affect skin condition on aged people. The purpose of this pilot study was to observe the in vivo effects on skin aging of topical DHEA (1%). METHODS: The DHEA formulation (1%) or the vehicle was topically applied for 4 months to facial and hand skin, in two groups of 20 post-menopausal women. The efficacy of the treatment was evaluated on the basis of clinical and biophysical signs linked to skin aging. RESULTS: We showed that DHEA treatment increased the rate of sebum, which was perceived rather positively by a menopausal population usually affected with a declining sebum level. Topical DHEA tends to improve skin brightness, to counteract papery appearance of skin and epidermal atrophy, a characteristic feature of hormone-related skin aging. Topical DHEA could also act on skin process related to wrinkles, but this result remains to be confirmed. CONCLUSIONS: This pilot study showed beneficial effects on skin characteristics that are rarely provided by topical treatments. It raised some interesting clues towards the treatment of skin aging.  相似文献   
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Identifying mutations in the TP53 gene is important for cancer prognosis, predicting response to therapy, and determining genetic risk. We have developed a high-throughput scanning assay with automatic calling to detect TP53 mutations in DNA from fresh frozen (FF) and formalin-fixed paraffin-embedded (FFPE) tissues. The coding region of the TP53 gene (exons 2-11) was PCR-amplified from breast cancer samples and scanned by high-resolution fluorescent melting curve analyses using a 384-well format in the LightCycler 480 instrument. Mutations were confirmed by direct sequencing. Sensitivity and specificity of scanning and automatic mutation calling was determined for FF tissue (whole genome amplified [WGA] and non-WGA) and FFPE tissue. Thresholds for automatic mutation calling were established for each preparation type. Overall, we confirmed 27 TP53 mutations in 68 primary breast cancers analyzed by high-resolution melting curve scanning and direct sequencing. Using scanning and automatic calling, there was high specificity (>95%) across all DNA preparation methods. Sensitivities ranged from 100% in non-WGA DNA from fresh tissue to 86% in WGA DNA and DNA from formalin-fixed, paraffin-embedded tissue. Scanning could detect mutated DNA at a dilution of 1:200 in a background of wild-type DNA. Mutation scanning by high-resolution fluorescent melting curve analyses can be done in a high-throughput and automated fashion. The TP53 scanning assay can be performed from a variety of specimen types with high sensitivity/specificity and could be used for clinical and research purposes.  相似文献   
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Recent case reports describe multidrug-resistant influenza A pandemic (H1N1) 2009 virus infection in immunocompromised patients exposed to neuraminidase inhibitors because of an I223R neuraminidase mutation. We report a case of multidrug-resistant pandemic (H1N1) 2009 bearing the I223R mutation in an ambulatory child with no previous exposure to neuraminidase inhibitors.  相似文献   
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Weight loss is a popular topic and may be of serious concern for many patients. Even with the abundant literature on obesity and cardiometabolic risk, it is always challenging to demystify and reinforce the determinants of safe approaches to lose weight. Measures of central obesity are essential to characterize the patient’s adiposity distribution and should be part of the routine medical examination. Beyond this, screening for fasting lipids and glucose are important for the assessment of the cardiometabolic risk which may lead to increased cardiovascular morbidity and mortality. Differences in adiposity as well as in weight loss exist between sexes and should be taken into consideration. Rather than avoiding some food or following certain type of diet, any planned weight loss interventions should promote lifestyle and environmental modifications with healthy eating and appropriate physical activity. With clear objectives, this appears to be the best way in order to achieve weight loss goals permanently.  相似文献   
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Mood disorders are amongst the most prevalent and severe disorders worldwide, with a tendency to be recurrent and disabling. Although multiple mechanisms have been hypothesized to be involved in their pathogenesis, just a few integrative theoretical frameworks have been proposed and have yet to integrate comprehensively all available findings. As such, a comprehensive framework would be quite useful from a clinical and therapeutic point of view in order to identify elements to evaluate and target in the clinical practice. Because conditions of sleep loss, which include reduced sleep duration and insomnia, are constant alterations in mood disorders, the aim of this paper was to review the literature on their potential role in the pathogenesis of mood disorders and to propose a novel theoretical model. According to this hypothesis, sleep should be considered the main regulator of several systems and processes whose dysregulation is involved in the pathogenesis of mood disorders. The model may help explain why sleep disturbances are so strikingly linked to mood disorders, and underscores the need to evaluate, assess and target sleep disturbances in clinical practice, as a priority, in order to prevent and treat mood disorders.  相似文献   
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