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Introduction: Brain-derived neurotrophic factor (BDNF) plays a key role in neural development and synaptic plasticity. BDNF is known to circulate in plasma and its levels are strictly linked to the sex hormones.

Aim: The aim of this study was to assess the plasma BDNF concentration in patients with Turner syndrome (TS). This is a first of such study in TS women.

Methods: 31 TS patients were enrolled to the study and compared with a control group (10 healthy, ovulatory women). We collected blood for measurement of BDNF plasma concentration, estradiol (E2) and gonadotrophins serum levels. The blood was taken after overnight fasting, in menstruating women in follicular phase.

Results: We found that BDNF plasma concentration was significantly higher in the group of TS patients compared to the control group (mean 768.5?±?194.9?pg/ml versus 407.2?±?25.7?pg/ml; p?r?=?0.92; p?Conclusions: In this study, we showed for the first time that TS patients has a higher BDNF levels than healthy ones and BDNF is not correlated with E2 concentration but tend to be related to testosterone. This study brings interesting insights to BDNF physiology.  相似文献   
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In this study, we tested five compounds belonging to a novel series of piperazine arylideneimidazolones for the ability to inhibit the AcrAB-TolC efflux pump. The biphenylmethylene derivative (BM-19) and the fluorenylmethylene derivative (BM-38) were found to possess the strongest efflux pump inhibitor (EPI) activities in the AcrAB-TolC-overproducing Escherichia coli strain 3-AG100, whereas BM-9, BM-27, and BM-36 had no activity at concentrations of up to 50 μM in a Nile red efflux assay. MIC microdilution assays demonstrated that BM-19 at 1/4 MIC (intrinsic MIC, 200 μM) was able to reduce the MICs of levofloxacin, oxacillin, linezolid, and clarithromycin 8-fold. BM-38 at 1/4 MIC (intrinsic MIC, 100 μM) was able to reduce only the MICs of oxacillin and linezolid (2-fold). Both compounds markedly reduced the MIC of rifampin (BM-19, 32-fold; and BM-38, 4-fold), which is suggestive of permeabilization of the outer membrane as an additional mechanism of action. Nitrocefin hydrolysis assays demonstrated that in addition to their EPI activity, both compounds were in fact weak permeabilizers of the outer membrane. Moreover, it was found that BM-19, BM-27, BM-36, and BM-38 acted as near-infrared-emitting fluorescent membrane probes, which allowed for their use in a combined influx and efflux assay and thus for tracking of the transport of an EPI across the outer membrane by an efflux pump in real time. The EPIs BM-38 and BM-19 displayed the most rapid influx of all compounds, whereas BM-27, which did not act as an EPI, showed the slowest influx.  相似文献   
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Despite limited and ambiguous empirical data, substance use-related problems have been assumed to be rare among patients with autism spectrum disorders (ASD). Using Swedish population-based registers we identified 26,986 individuals diagnosed with ASD during 1973–2009, and their 96,557 non-ASD relatives. ASD, without diagnosed comorbidity of attention deficit hyperactivity disorder (ADHD) or intellectual disability, was related to a doubled risk of substance use-related problems. The risk of substance use-related problems was the highest among individuals with ASD and ADHD. Further, risks of substance use-related problems were increased among full siblings of ASD probands, half-siblings and parents. We conclude that ASD is a risk factor for substance use-related problems. The elevated risks among relatives of probands with ASD suggest shared familial (genetic and/or shared environmental) liability.  相似文献   
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