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881.
Studies in humans and animal models link maternal infection and imbalanced levels of inflammatory mediators in the foetal brain to the aetiology of neuropsychiatric disorders. In a number of animal models, it was shown that exposure to viral or bacterial agents during a period that corresponds to the second trimester in human gestation triggers brain and behavioural abnormalities in the offspring. However, little is known about the early cellular and molecular events elicited by inflammation in the foetal brain shortly after maternal infection has occurred. In this study, maternal infection was mimicked by two consecutive intraperitoneal injections of 200 μg of LPS (lipopolysaccharide)/kg to timed-pregnant rats at GD15 (gestational day 15) and GD16. Increased thickness of the CP (cortical plate) and hippocampus together with abnormal distribution of immature neuronal markers and decreased expression of markers for neural progenitors were observed in the LPS-exposed foetal forebrains at GD18. Such effects were accompanied by decreased levels of reelin and the radial glial marker GLAST (glial glutamate transporter), and elevated levels of pro-inflammatory cytokines in maternal serum and foetal forebrains. Foetal inflammation elicited by maternal injections of LPS has discrete detrimental effects on brain development. The early biochemical and morphological changes described in this work begin to explain the sequelae of early events that underlie the neurobehavioural deficits reported in humans and animals exposed to prenatal insults.  相似文献   
882.
Psilocybe argentipes is a hallucinogenic mushroom. The present study examined the effects of P. argentipes on marble-burying behavior, which is considered an animal model of obsessive-compulsive disorder. P. argentipes significantly inhibited marble-burying behavior without affecting locomotor activity as compared with the same dose of authentic psilocybin. These findings suggest that P. argentipes would be efficient in clinical obsessive-compulsive disorder therapy.  相似文献   
883.
Generalized anxiety disorder (GAD) is a psychiatric disorder characterized by a constant and unspecific anxiety that interferes with daily-life activities. Its high prevalence in general population and the severe limitations it causes, point out the necessity to find new efficient strategies to treat it. Together with the cognitive-behavioral treatments, relaxation represents a useful approach for the treatment of GAD, but it has the limitation that it is hard to be learned. The INTREPID project is aimed to implement a new instrument to treat anxiety-related disorders and to test its clinical efficacy in reducing anxiety-related symptoms. The innovation of this approach is the combination of virtual reality and biofeedback, so that the first one is directly modified by the output of the second one. In this way, the patient is made aware of his or her reactions through the modification of some features of the VR environment in real time. Using mental exercises the patient learns to control these physiological parameters and using the feedback provided by the virtual environment is able to gauge his or her success. The supplemental use of portable devices, such as PDA or smart-phones, allows the patient to perform at home, individually and autonomously, the same exercises experienced in therapist''s office. The goal is to anchor the learned protocol in a real life context, so enhancing the patients'' ability to deal with their symptoms. The expected result is a better and faster learning of relaxation techniques, and thus an increased effectiveness of the treatment if compared with traditional clinical protocols.  相似文献   
884.
We have shown preferential expression of both mRNA and corresponding protein for myosin VI (Myo6) in the murine hippocampus within 24 h after the extreme traumatic experience, water-immersion restraint stress (WIRS), prior to a drastic decrease in neural progenitor proliferation in the dentate gyrus. Myosin (Myo6) protein levels were significantly increased in hippocampus within 24 h after flashback experience in mice previously exposed to WIRS. Myo6 protein was ubiquitously distributed in discrete mouse brain regions with exceptionally high expression in olfactory bulb, whereas Myo6 protein was expressed in cultured rat astroglia and neurons, in addition to Myo6 mRNA expression by cultured neural progenitors. In mouse embryonal carcinoma P19 cells endowed to proliferate and differentiate, Myo6 protein was expressed in line with astroglial marker protein expression. Transient over-expression of Myo6 induced a significant decrease in the size of clustered aggregates as an index of self-replication in P19 cells. Immunoprecipitation analysis revealed the interaction between Myo6 and the RNA-binding protein, translocated in liposarcoma (TLS), while TLS was predominantly expressed by neurons in the cortex, striatum, cerebellum, and hippocampus. These results suggest that Myo6 may play a pivotal role in the mechanism underlying the suppressed adult neurogenesis after traumatic stress in association with TLS.  相似文献   
885.
Zellweger spectrum disorder (ZSD) results from biallelic mutations in PEX genes required for peroxisome biogenesis. PEX1-G843D is a common hypomorphic allele in the patient population that is associated with milder disease. In prior work using a PEX1-G843D/null patient fibroblast line expressing a green fluorescent protein (GFP) reporter with a peroxisome-targeting signal (GFP-PTS1), we demonstrated that treatments with the chemical chaperone betaine and flavonoid acacetin diacetate recovered peroxisome functions. To identify more effective compounds for preclinical investigation, we evaluated 54 flavonoids using this cell-based phenotype assay. Diosmetin showed the most promising combination of potency and efficacy (EC50 2.5 µM). All active 5′,7′-dihydroxyflavones showed greater average efficacy than their corresponding flavonols, whereas the corresponding flavanones, isoflavones, and chalcones tested were inactive. Additional treatment with the proteostasis regulator bortezomib increased the percentage of import-rescued cells over treatment with flavonoids alone. Cotreatments of diosmetin and betaine showed the most robust additive effects, as confirmed by three independent functional assays in primary PEX1-G843D patient cells, but neither agent was active alone or in combination in patient cells homozygous for the PEX1 c.2097_2098insT null allele. Moreover, diosmetin treatment increased PEX1, PEX6, and PEX5 protein levels in PEX1-G843D patient cells, but none of these proteins increased in PEX1 null cells. We propose that diosmetin acts as a pharmacological chaperone that improves the stability, conformation, and functions of PEX1/PEX6 exportomer complexes required for peroxisome assembly. We suggest that diosmetin, in clinical use for chronic venous disease, and related flavonoids warrant further preclinical investigation for the treatment of PEX1-G843D–associated ZSD.  相似文献   
886.
Neuroimmune dysfunction is a cardinal feature of neurodegenerative diseases. But how immune dysregulation in the brain and peripheral organs contribute to neurodegeneration remains unclear. Here, we discuss the recent advances highlighting neuroimmune dysfunction as a key disease-driving factor in frontotemporal dementia (FTD). We provide an overview of the clinical observations supporting a high prevalence of autoimmune diseases in FTD patients with mutations in GRN or C9orf72. We then focus on a myriad of evidence from human genetic studies, mouse models, in vitro assays, and multi-omics platform, which indicate that haploinsufficiency in GRN and C9orf72 promotes neuroimmune dysfunction and contributes to neurodegeneration and premature death. These compelling data provide key insights to disease mechanisms, biomarker discovery, and therapeutic interventions for FTD (120 words).  相似文献   
887.
Thymosin β4 (Tβ4), a G-actin-sequestering secreted peptide, improves neurovascular remodeling and central nervous system plasticity, which leads to neurological recovery in many neurological diseases. Inflammatory response adjustment and tissue inflammation consequences from neurological injury are vital for neurological recovery. The innate or nonspecific immune system is made of different components. The Toll-like receptor pro-inflammatory signaling pathway, which is one of these components, regulates tissue injury. The main component of the Toll-like/IL-1 receptor signaling pathway, which is known as IRAK1, can be regulated by miR-146a and regulates NF-κB expression. Due to the significant role of Tβ4 in oligodendrocytes, neurons, and microglial cells in neurological recovery, it is suggested that Tβ4 regulates the Toll-like receptor (TLR) pro-inflammatory signaling pathway by upregulating miR-146a in neurological disorders. However, further investigations on the role of Tβ4 in regulating the expression of miR146a and TLR signaling pathway in the immune response adjustment in neurological disorders provides an insight into mechanisms of action and the possibility of Tβ4 therapeutic effect enhancement.  相似文献   
888.
To explain the pattern of preserved and superior abilities found in autism spectrum disorders, a hypothesis has emerged, which assumes that there is a developmental bias towards the formation of short-range connections. This would result in excessive activity and overconnectivity within susceptible local networks. These networks might become partially isolated and acquire novel functional properties. In turn, this would affect the formation of long-range circuits and systems governing top-down control and integration. Despite many tantalizing clues, mechanisms relating pathogenesis and altered cell function to the ‘disconnection’ of integrative and focal activity remain obscure. However, recent post-mortem studies of brains of individuals with autism have shown characteristic differences in the morphometry of radial cell minicolumns, which add credence to the connectivity hypothesis.  相似文献   
889.
890.
This study aims to describe the 24-hour activity rhythm in adults with attention-deficit/hyperactivity disorder (ADHD). A total of 18 ADHD patients and 37 healthy controls (HCs) wore an actigraph for 7 days. ADHD patients showed higher motor activity than HCs at 4:00, 6:00, 15:00 and 16:00 hour. Within the theoretical framework of the two-process model of sleep regulation, the observed data may be explained by lower homeostatic sleep pressure in ADHD. This could lead to an increase in motor activity in the second half of the night, when sleep need decreases more rapidly, and in the first half of the afternoon, when patients do not experience the typical post-lunch dip.  相似文献   
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