2,429 research outputs found

    High-Speed imaging reveals opposing effects of chronic stress and antidepressants on neuronal activity propagation through the hippocampal trisynaptic circuit

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    Antidepressants (ADs) are used as first-line treatment for most stress-related psychiatric disorders. The alterations in brain circuit dynamics that can arise from stress exposure and underlie therapeutic actions of ADs remain, however, poorly understood. Here, enabled by a recently developed voltage-sensitive dye imaging (VSDI) assay in mouse brain slices, we examined the impact of chronic stress and concentration-dependent effects of eight clinically used ADs (belonging to different chemical/functional classes) on evoked neuronal activity propagations through the hippocampal trisynaptic circuitry (HTC: perforant path -> dentate gyrus (DG) -> area CA3 -> area CA1). Exposure of mice to chronic social defeat stress led to markedly weakened activity propagations ("HTC-Waves"). In contrast, at concentrations in the low micromolar range, all ADs, which were bath applied to slices, caused an amplification of HTC-Waves in CA regions (invariably in area CA1). The fast-acting "antidepressant" ketamine, the mood stabilizer lithium, and brain derived neurotrophic factor (BDNF) exerted comparable enhancing effects, whereas the antipsychotic haloperidol and the anxiolytic diazepam attenuated HTC-Waves. Collectively, we provide direct experimental evidence that chronic stress can depress neuronal signal flow through the HTC and demonstrate shared opposing effects of ADs. Thus, our study points to a circuit level mechanism of ADs to counteract stress-induced impairment of hippocampal network function. However, the observed effects of ADs are impossible to depend on enhanced neurogenesis

    From first‐trimester screening to risk stratification of evolving pre‐eclampsia in second and third trimesters of pregnancy: comprehensive approach

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    Preeclampsia and associated hypertensive disorders of pregnancy represent a leading cause of global maternal and neonatal morbidity and mortality. Identification of women at high risk for developing preterm-preeclampsia and prophylaxis with low-dose aspirin has the potential to significantly reduce the rate of preterm-preeclampsia. In addition, risk assessment and monitoring of women in the second and third trimester of pregnancy, to aid in early detection of evolving disease, timely referral to specialist care, and active monitoring of women with confirmed or suspected preeclampsia is essential for improving maternal and neonatal outcomes. The angiogenesis-related biomarkers sFlt-1 and PlGF have been shown to have clinical value to aid in the prediction, diagnosis, and risk stratification of preeclampsia when used either alone or in combination with other risk factors. However, currently there is no consensus on the optimum strategy to link first trimester screening for preterm-preeclampsia with appropriate second and third trimester risk assessment strategies. This opinion paper will outline the current evidence for first trimester preeclampsia screening and prevention, as well as the evidence for various risk stratification approaches for detection of evolving preeclampsia through the second and third trimesters of pregnancy, and proposes a potential model integrating these tools. This article is protected by copyright. All rights reserved

    Efficacy of teriparatide compared with risedronate on FRAX®-defined major osteoporotic fractures. results of the VERO clinical trial

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    Summary: FRAX® calculates the 10-year probability of major osteoporotic fractures (MOF), which are considered to have a greater clinical impact than other fractures. Our results suggest that, in postmenopausal women with severe osteoporosis, those treated with teriparatide had a 60% lower risk of FRAX®-defined MOF compared with those treated with risedronate. Introduction: The VERO trial was an active-controlled fracture endpoint clinical trial that enrolled postmenopausal women with severe osteoporosis. After 24 months, a 52% reduction in the hazard ratio (HR) of clinical fractures was reported in patients randomized to teriparatide compared with risedronate. We examined fracture results restricted to FRAX®-defined major osteoporotic fractures (MOF), which include clinical vertebral, hip, humerus, and forearm fractures. Methods: In total, 1360 postmenopausal women (mean age 72.1 years) were randomized to receive subcutaneous daily teriparatide (20 μg) or oral weekly risedronate (35 mg). Patient cumulative incidence of ≥ 1 FRAX®-defined MOF and of all clinical fractures were estimated by Kaplan-Meier analyses, and the comparison between treatments was based on the stratified log-rank test. Additionally, an extended Cox model was used to estimate HRs at different time points. Incidence fracture rates were estimated at each 6-month interval. Results: After 24 months, 16 (2.6%) patients in the teriparatide group had ≥ 1 low trauma FRAX®-defined MOF compared with 40 patients (6.4%) in the risedronate group (HR 0.40; 95% CI 0.23–0.68; p = 0.001). Clinical vertebral and radius fractures were the most frequent FRAX®-defined MOF sites. The largest difference in incidence rates of both FRAX®-defined MOF and all clinical fractures between treatments occurred during the 6- to 12-month period. There was a statistically significant reduction in fractures between groups as early as 7 months for both categories of clinical fractures analyzed. Conclusion: In postmenopausal women with severe osteoporosis, treatment with teriparatide was more efficacious than risedronate, with a 60% lower risk of FRAX®-defined MOF during the 24-month treatment period. Fracture risk was statistically significantly reduced at 7 months of treatment. Clinical trial information: ClinicalTrials.gov Identifier: NCT01709110 EudraCT Number: 2012-000123-41

    Paucity and preferential suppression of transgenes in late replication domains of the D. melanogaster genome

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    <p>Abstract</p> <p>Background</p> <p>Eukaryotic genomes are organized in extended domains with distinct features intimately linking genome structure, replication pattern and chromatin state. Recently we identified a set of long late replicating euchromatic regions that are underreplicated in salivary gland polytene chromosomes of <it>D. melanogaster</it>.</p> <p>Results</p> <p>Here we demonstrate that these underreplicated regions (URs) have a low density of <it>P</it>-<it>element </it>and <it>piggyBac </it>insertions compared to the genome average or neighboring regions. In contrast, <it>Minos</it>-based transposons show no paucity in URs but have a strong bias to testis-specific genes. We estimated the suppression level in 2,852 stocks carrying a single <it>P</it>-<it>element </it>by analysis of eye color determined by the mini-<it>white </it>marker gene and demonstrate that the proportion of suppressed transgenes in URs is more than three times higher than in the flanking regions or the genomic average. The suppressed transgenes reside in intergenic, genic or promoter regions of the annotated genes. We speculate that the low insertion frequency of <it>P-elemen</it>ts and <it>piggyBac</it>s in URs partially results from suppression of transgenes that potentially could prevent identification of transgenes due to complete suppression of the marker gene. In a similar manner, the proportion of suppressed transgenes is higher in loci replicating late or very late in Kc cells and these loci have a lower density of <it>P-elements </it>and <it>piggyBac </it>insertions. In transgenes with two marker genes suppression of mini-<it>white </it>gene in eye coincides with suppression of <it>yellow </it>gene in bristles.</p> <p>Conclusions</p> <p>Our results suggest that the late replication domains have a high inactivation potential apparently linked to the silenced or closed chromatin state in these regions, and that such inactivation potential is largely maintained in different tissues.</p

    Lorentz-Abraham-Dirac vs Landau-Lifshitz radiation friction force in the ultrarelativistic electron interaction with electromagnetic wave (exact solutions)

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    When the parameters of electron - extreme power laser interaction enter the regime of dominated radiation reaction, the electron dynamics changes qualitatively. The adequate theoretical description of this regime becomes crutially important with the use of the radiation friction force either in the Lorentz-Abraham-Dirac form, which possess unphysical runaway solutions, or in the Landau-Lifshitz form, which is a perturbation valid for relatively low electromagnetic wave amplitude. The goal of the present paper is to find the limits of the Landau-Lifshitz radiation force applicability in terms of the electromagnetic wave amplitude and frequency. For this a class of the exact solutions to the nonlinear problems of charged particle motion in the time-varying electromagnetic field is used.Comment: 14 pages, 5 figure

    A Statistical Inference Method for Interpreting the CLASP Observations

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    On 3rd September 2015, the Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) successfully measured the linear polarization produced by scattering processes in the hydrogen Lyman-α\alpha line of the solar disk radiation, revealing conspicuous spatial variations in the Q/IQ/I and U/IU/I signals. Via the Hanle effect the line-center Q/IQ/I and U/IU/I amplitudes encode information on the magnetic field of the chromosphere-corona transition region (TR), but they are also sensitive to the three-dimensional structure of this corrugated interface region. With the help of a simple line formation model, here we propose a statistical inference method for interpreting the Lyman-α\alpha line-center polarization observed by CLASP.Comment: Accepted for publication in The Astrophysical Journa

    The influence of different pathogens on the lysozyme activity into tissues of rat oral cavity

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    Aim: To determine action of the different pathogens on the lysozyme activity into tissues of oral cavity and serum.Methods: The lysozyme activities was determined into oral mucosa cheek, tongue gum and serum of 158 white rats (11 series experiments). The pathogens were used: atropine, protamine sulfat, indometacyn, bee poison, hydrasine sulfat, cytostatic cyclofosfan, lincomycin, lipopolysaccharide, composition of antibiotic and omeprasol for ACBTResults: The  whole of pathogens decreased lysozyme activity (mean in 1,6-2,5 times) into oral tissues and on 16 % into serum. The specific lowering of lysozyme activities (Δ%/mg pathogen) was low most for lipopolysaccharide, especially after oral application usage (exceeding was in tens times).Conclusion: The lysozyme activity lowering may play significant role in pathogenesis of stomatologic diseases/ Lipopolysaccharide (LPS) send lysozyme activity lowering most especially after oral application. Probably, the antilysozyme action of pathogens realize by LPS. The stomatogenic factor in pathogenesis and profilactic of noninfection diseases is important

    Deposition of impurity metals during campaigns with the JET ITER-like Wall

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    Post mortem analysis shows that mid and high atomic number metallic impurities are present in deposits on JET plasma facing components with the highest amount of Ni and W, and therefore the largest sink, being found at the top of the inner divertor. Sources are defined as “continuous” or “specific”, in that “continuous” sources arise from ongoing erosion from plasma facing surfaces and “specific” are linked with specific events which decrease over time until they no longer act as a source. This contribution evaluates the sinks and estimates sources, and the balance gives an indication of the dominating processes. Charge exchange neutral erosion is found to be the main source of nickel, whereas erosion of divertor plasma facing components is the main source of tungsten. Specific sources are shown to have little influence over the global mid- and high-Z impurity concentrations in deposits.Peer reviewe

    XPS Study of Ion Irradiated and Unirradiated UO2 Thin Films.

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    XPS determination of the oxygen coefficient kO = 2 + x and ionic (U(4+), U(5+), and U(6+)) composition of oxides UO2+x formed on the surfaces of differently oriented (hkl) planes of thin UO2 films on LSAT (Al10La3O51Sr14Ta7) and YSZ (yttria-stabilized zirconia) substrates was performed. The U 4f and O 1s core-electron peak intensities as well as the U 5f relative intensity before and after the (129)Xe(23+) and (238)U(31+) irradiations were employed. It was found that the presence of uranium dioxide film in air results in formation of oxide UO2+x on the surface with mean oxygen coefficients kO in the range 2.07-2.11 on LSAT and 2.17-2.23 on YSZ substrates. These oxygen coefficients depend on the substrate and weakly on the crystallographic orientation. On the basis of the spectral parameters it was established that uranium dioxide films AP2,3 on the LSAT substrates have the smallest kO values, and from the XRD and EBSD results it follows that these samples have a regular monocrystalline structure. The XRD and EBSD results indicate that samples AP5-7 on the YSZ substrates have monocrystalline structure; however, they have the highest kO values. The observed difference in the kO values was probably caused by the different nature of the substrates: the YSZ substrates provide 6.4% compressive strain, whereas (001) LSAT substrates result only in 0.03% tensile strain in the UO2 films. (129)Xe(23+) irradiation (92 MeV, 4.8 × 10(15) ions/cm(2)) of uranium dioxide films on the LSAT substrates was shown to destroy both long-range ordering and uranium close environment, which results in an increase of uranium oxidation state and regrouping of oxygen ions in uranium close environment. (238)U(31+) (110 MeV, 5 × 10(10), 5 × 10(11), 5 × 10(12) ions/cm(2)) irradiations of uranium dioxide films on the YSZ substrates were shown to form the lattice damage only with partial destruction of the long-range ordering.The irradiation experiment was performed at the Grand Accelé rateur National d ́ ’Ions Lourds (GANIL) Caen, France, and supported by the French Network EMIR. The support in planning and execution of the experiment by the CIMAPCIRIL and the GANIL staff, especially I. Monnet, C. Grygiel, T. Madi, and F. Durantel, is much appreciated. The work was supported by RFBR grant no. 16-03-00914-a and partially supported by M.V. Lomonosov Moscow State University Program of Development. A.J.P. acknowledges funding from the UK EPSRC (grant EP/I036400/1) and Radioactive Waste Management Ltd. (formerly the Radioactive Waste Management Directorate of the UK Nuclear Decommissioning Authority, contract NPO004411A-EPS02), a maintenance grant from the Russian Foundation for Basic Research (projects 13-03-90916) and CSAR bursary. Thanks are given to A.M. Adamska, G.I. Lampronti, V.A. Lebedev, P.G. Martin, L. Payne, and A.A. Shiryaev for their help in characterization of the samples
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