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Background

Major depressive disorder (MDD) is a multifactorial disease which often coexists with cognitive deficits. Depression-induced cognitive deficits are known to be associated with aberrant reward processing, neurochemical and structural alterations. Recent studies have shown that chronic electrical stimulation of brain reward areas induces a robust antidepressant effect. However, the effects of repeated electrical self-stimulation of lateral hypothalamus - medial forebrain bundle (LH-MFB) on depression-induced cognitive deficits and associated neurochemical and structural alterations in the prefrontal cortex (PFC) are unknown.

Objectives

We investigated the effect of chronic rewarding self-stimulation of LH-MFB in neonatal clomipramine (CLI) model of depression. During adulthood, neonatal CLI and saline administered rats were implanted with bilateral electrodes stereotaxically in the LH-MFB and trained to receive intracranial self-stimulation (ICSS) for 14 days. The rats were tested for depressive-like behaviors, learning and memory followed by estimation of PFC volumes, levels of monoamines and its metabolites in the PFC.

Results

We found that chronic ICSS of LH-MFB reverses CLI-induced behavioral despair and anhedonia. Interestingly, self-stimulation normalizes the impaired novel object and location recognition memory in CLI rats. The amelioration of learning impairments in CLI rats was associated with the reversal of volume loss and restoration of monoamine metabolism in the PFC.

Conclusion

We demonstrated that repeated intracranial self-stimulation of LH-MFB ameliorates CLI-induced learning deficits, reverses altered monoamine metabolism and the atrophy of PFC. Our results support the hypothesis that chronic brain stimulation rewarding experience might be evolved as a potential treatment strategy for reversal of learning deficits in depression and associated disorders.  相似文献   
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Although histopathology is the time‐honored gold standard diagnostic measure in dermatology, several factors may detract from an accurate microscopic diagnosis. Limiting factors include: human error, suboptimal biopsy‐site selection or biopsy technique, and inherent restrictions of vertical tissue sectioning that lead to incomplete microscopic evaluation of the lesion. Reflectance confocal microscopy (RCM) is a non‐invasive imaging tool that allows for the cellular‐level examination of the lesion, at a horizontal plane, which may complement the subsequent vertical histopathological tissue examination. Herein, we report a case series whereby prebiopsy RCM examination enhanced the accuracy of histopathological diagnosis or allowed for a critical appraisal of initial histopathological misdiagnosis.  相似文献   
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This review forms part of a series of annual updates that summarize the evidence base for atopic eczema (AE). It provides a summary of key findings from 25 systematic reviews that were published or indexed during 2017, and focuses on the treatment and prevention of AE. There is high‐quality evidence to demonstrate that dupilumab is better than placebo for the treatment of AE, is not associated with a higher incidence of adverse effects and does not increase the risk of infection compared with placebo; however, comparison studies with other systemic treatments are necessary. Topical tofacitinib is a promising treatment for mild–moderate AE, but currently lacks sufficient evidence from well‐designed randomized controlled trials (RCTs) comparing with other active treatments. Topical doxepin may be effective for pruritus in AE, but available studies have short follow‐up periods and longer‐term outcomes are needed. Bleach baths were no more effective than water baths alone at reducing AE severity. Topical antibiotics cannot be recommended for infected AE, owing to insufficient evidence of benefit. There is little comparison of different emollients in RCTs, but overall evidence indicates that they reduce AE severity, are steroid‐sparing and lead to better outcomes in combination with topical corticosteroids (TCS) than TCS alone. No clear benefit was demonstrated for vitamin D/C/E supplementation in pregnancy for eczema prevention.  相似文献   
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Well‐known causes of zinc deficiency, also referred to as acrodermatitis enteropathica (AE), include defects in intestinal zinc transporters and inadequate intake, but a rare cause of acquired zinc deficiency discussed here is an iatrogenic nutritional deficiency caused by parenteral nutrition administered without trace elements. While zinc‐depleted parenteral nutrition causing dermatosis of acquired zinc deficiency was first reported in the 1990s, it is now again relevant due to a national vitamin and trace element shortage. A high index of suspicion may be necessary to diagnose zinc deficiency, particularly because early clinical findings are nonspecific. We present this case of acquired zinc deficiency in a patient admitted to a pediatric intensive care unit for respiratory distress and atypical pneumonia, who subsequently developed a severe bullous eruption due to iatrogenic zinc deficiency but was treated effectively with enteral and parenteral zinc supplementation, allowing for rapid re‐epithelialization of previously denuded skin.  相似文献   
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