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Major depression has been repeatedly associated with amygdala hyper‐responsiveness to negative (but not positive) facial expressions at early, automatic stages of emotion processing using subliminally presented stimuli. However, it is not clear whether this “limbic bias” is a correlate of depression or represents a vulnerability marker preceding the onset of the disease. Because childhood maltreatment is a potent risk factor for the development of major depression in later life, we explored whether childhood maltreatment is associated with amygdalar emotion processing bias in maltreated but healthy subjects. Amygdala responsiveness to subliminally presented sad and happy faces was measured by means of fMRI at 3 T in N = 150 healthy subjects carefully screened for psychiatric disorders. Childhood maltreatment was assessed by the 25‐item childhood trauma questionnaire (CTQ). A strong association of CTQ‐scores with amygdala responsiveness to sad, but not happy facial expressions emerged. This result was further qualified by an interaction of emotional valence and CTQ‐scores and was not confounded by trait anxiety, current depression level, age, gender, intelligence, education level, and more recent stressful life‐events. Childhood maltreatment is apparently associated with detectable changes in amygdala function during early stages of emotion processing which resemble findings described in major depression. Limbic hyper‐responsiveness to negative facial cues could be a consequence of the experience of maltreatment during childhood increasing the risk of depression in later life. Limitation: the present association of limbic bias and maltreatment was demonstrated in the absence of psychopathological abnormalities, thereby limiting strong conclusions. Hum Brain Mapp 34:2899–2909, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Introduction

The Adverse Event Scale in Patients With Epilepsy (aESCAPE) European study (NCT00394927) explored and analyzed adverse events (AEs) and reasons for modifying treatment in patients treated with newer and older antiepileptic drugs (AEDs) used in monotherapy or polytherapy. The present analysis concerns the results of patients recruited in Poland.

Material and methods

Multicentre, international, observational, cross-sectional study investigating AEs in patients with epilepsy (aged ≥ 4 years), on stable AED treatment with one or two AED(s) for ≥ 3 months, using standardized questionnaires completed by a physician during a single study visit.

Results

Out of 309 patients, 24.6% were treated exclusively with newer AED(s) in monotherapy or in combination, while 75.4% were treated with older AED(s) or a combination of older and newer AED(s). 60.8% were on monotherapy, and 39.9% on polytherapy. In general, 73.8% of patients reported ≥ 1 AE(s). There were no significant differences in the frequency of reported AEs in compared groups. The most common were disturbances in cognitive function (40.5%), psychological problems (36.2%), and sedation (32.7%). Some AEs were found to be more specific for particular types and treatment regimens. Changes in treatment or dose during the study visit occurred in 22.3% of the patients, mainly due to lack of efficacy (10.7%), AEs (5.2%) or absence of seizures (4.5%).

Conclusions

A detailed structured interview revealed high frequency of AEs in patients treated with AEDs. The main reasons for treatment modifications at the study visit were lack of efficacy, adverse events and absence of seizures.  相似文献   
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Background. Chronic kidney disease (CKD) is associated with muscle excess fatigue and diminished maximal whole body oxygen consumption, which in part could be depended on poor muscle microcirculatory network. The aim of this study was to assume the influence of different stages of CKD on microcirculation vessels in functionally different skeletal muscles—locomotor, the gastrocnemius muscle, and postural, the longissimus thoracis muscle. Methods. Male Wistar rats underwent sham operation (CON), uninephrectomy (CKD 1/2) and subtotal nephrectomy (CKD 5/6). Muscle samples were stained for an alkaline phosphatase to differentiate capillaries. The number of capillaries was estimated by a single observer in 10 μm transverse sections by point counting at a magnification of ×125 using an Image Analysis System Q 500 MC of Leica. Blood pressure and serum creatinine, haptoglobin, MCP-1, VEGF, and PDGF were measured. Results. There were significant differences (p < 0.05) in CD (number of capillaries per 1 mm2 of muscle tissue), C:F (capillary to fiber ratio), and CC/F (capillary contact per fiber). The CKD 1/2 group in gastrocnemius and longissimus muscle had 53% and 33% lower C:F; 56% and 33% lower CD; and 44% and 20% less CC/F than CON, respectively. The CKD 5/6 group in gastrocnemius and longissimus muscle had 46% and 20% lower C:F; 47% and 11% lower CD; and 48% and 25% less CC/F versus control, respectively. Blood pressure was higher in CKD 5/6 vs. CKD 1/2 and CON (145/95 vs. 107/87 and 119/77 mmHg, p < 0.05, respectively). CKD 5/6 had higher creatinine than CKD 1/2 and CON (1.22 vs. 0.83 and 0.74 mg/dL, p < 0.05, respectively). Haptoglobin was higher in CKD 1/2 and CKD 5/6 versus CON (1.68 and 1.63 vs. 0.70 mg/mL, p < 0.05, respectively). MCP-1 was higher in CKD 5/6 and CKD 1/2 versus CON (609 and 489 vs. 292 pg/mL, p < 0.05, respectively). There were no significant differences in serum growth factors concentration between groups. Conclusion. Capillary rarefaction is present in early stages of CKD. These changes are independent of blood pressure and progression of CKD. We suspected that muscle function has a big impact on microvasculature as capillaries rarefaction has been reduced more in locomotor than postural skeletal muscle.  相似文献   
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Purpose

To compare task performances of novices and experts using advanced high-definition 3D versus 2D optical systems in a surgical simulator model.

Methods

Fifty medical students (novices in laparoscopy) were randomly assigned to perform five standardized tasks adopted from the Fundamentals of Laparoscopic Surgery (FLS) curriculum in either a 2D or 3D laparoscopy simulator system. In addition, eight experts performed the same tasks. Task performances were evaluated using a validated scoring system of the SAGES/FLS program. Participants were asked to rate 16 items in a questionnaire.

Results

Overall task performance of novices was significantly better using stereoscopic visualization. Superiority of performances in 3D reached a level of significance for tasks peg transfer and precision cutting. No significant differences were noted in performances of experts when using either 2D or 3D. Overall performances of experts compared to novices were better in both 2D and 3D. Scorings in the questionnaires showed a tendency toward lower scores in the group of novices using 3D.

Conclusions

Stereoscopic imaging significantly improves performance of laparoscopic phantom tasks of novices. The current study confirms earlier data based on a large number of participants and a standardized task and scoring system. Participants felt more confident and comfortable when using a 3D laparoscopic system. However, the question remains open whether these findings translate into faster and safer operations in a clinical setting.
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