91 research outputs found

    Maladaptive defensive behaviours in monoamine oxidase A-deficient mice

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    Rich evidence indicates that monoamine oxidase (MAO) A, the major enzyme catalysing the degradation of monoamine neurotransmitters, plays a key role in emotional regulation. Although MAOA deficiency is associated with reactive aggression in humans and mice, the involvement of this enzyme in defensive behaviour remains controversial and poorly understood. To address this issue, we tested MAOA knockout (KO) mice in a spectrum of paradigms and settings associated with variable degrees of threat. The presentation of novel inanimate objects induced a significant reduction in exploratory approaches and increase in defensive behaviours, such as tail-rattling, biting and digging. These neophobic responses were context-dependent and particularly marked in the home cage. In the elevated plus-and T-mazes, MAOA KO mice and wild-type (WT) littermates displayed equivalent locomotor activity and time in closed and open arms; however, MAOA KO mice featured significant reductions in risk assessment, as well as unconditioned avoidance and escape. No differences between genotypes were observed in the defensive withdrawal and emergence test. Conversely, MAOA KO mice exhibited a dramatic reduction of defensive and fear-related behaviours in the presence of predator-related cues, such as predator urine or an anaesthetized rat, in comparison with those observed in their WT littermates. The behavioural abnormalities in MAOA KO mice were not paralleled by overt alterations in sensory and microvibrissal functions. Collectively, these results suggest that MAOA deficiency leads to a general inability to appropriately assess contextual risk and attune defensive and emotional responses to environmental cues

    Cloning and expression of Aca f 1: A new allergen of Acacia farnesiana pollen

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    Acacia farnesiana is the main source of allergenic pollen and one of the most important causes of respiratory allergic disease in tropical and subtropical regions of the world. The purpose of this study was to produce a recombinant variety of allergenic Ole e 1-like protein from the pollen of this tree. To predict its allergenic cross-reactivity with other members of the Ole e 1-like protein family of common allergenic plants, the nucleotide sequence homology of the Acacia Ole e 1-like protein was evaluated. Amplification of cDNA strands encoding Acacia Ole e 1-like protein was performed by polymerase chain reaction (PCR) and sequenced. Following expression in Escherichia coli using the pET-21b(+) vector, the recombinant protein was purified using metal-affinity chromatography. IgE-binding competence of purified recombinant Ole e 1- like protein (rAca f 1) was analysed by immunoassay using 25 sera collected from Acacia pollen-sensitised patients. Nucleotide sequencing revealed an open reading frame of 453 bp encoding 150 amino acid residues that belonged to the Ole e 1-like protein family, and 11 patients (44) had considerable specific IgE levels for the rAca f 1. Immunodetection and inhibition assays indicated that the purified rAca f 1 may be the same as that in the crude extract. Aca f 1, the second allergen from Acacia pollen, was identified as a member of the family of Ole e 1-like protein. A high degree of homology was found among amino acid sequences of Aca f 1 and several allergenic members of Ole e 1-like protein family

    Cloning and Expression of Ama r 1, as a Novel Allergen of Amaranthus retroflexus Pollen

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    Sensitisation to Amaranthus retroflexus pollen is very common in tropical and subtropical countries. In this study we aimed to produce a recombinant allergenic Ole e 1-like protein from the pollen of this weed. To predict cross-reactivity of this allergen (Ama r 1) with other members of the Ole e 1-like protein family, the nucleotide sequence homology of the Ama r 1 was investigated. The expression of Ama r 1 in Escherichia coli was performed by using a pET-21b(+) vector. The IgE-binding potential of recombinant Ama r 1 (rAma r 1) was evaluated by immunodetection and inhibition assays using 26 patients' sera sensitised to A. retroflexus pollen. The coding sequence of the Ama r 1 cDNA indicated an open reading frame of 507 bp encoding for 168 amino acid residues which belonged to the Ole e 1-like protein family. Of the 26 serum samples, 10 (38.46) had significant specific IgE levels for rAma r 1. Immunodetection and inhibition assays revealed that the purified rAma r 1 might be the same as that in the crude extract. Ama r 1, the second allergen from the A. retroflexus pollen, was identified as a member of the family of Ole e 1-like protein. © 2016 Payam Morakabati et al

    Designing Tuneable Narrowband Bandpass Filter Utilizing Neural Network

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    Abstract: In this study we aim at adjusting the singleband and dualband bandpass filter designed in a ED02AH technology. The quality factor and center frequency of the filter will change by varactor diodes. Here, we use a neural network to acquire the proper biasing voltages of varactor diodes in order to obtain specific gain and quality factor

    Spectroscopic investigation and Judd-Ofelt analysis of silver nanoparticles embedded Er3+-doped tellurite glass

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    A series of silver nanoparticles (NPs) embedded zinc-tellurite glass is prepared by melt-quenching technique. The transmission electron microscopic images reveal spherical as well as anisotropic silver NPs having average diameter in the range of 14-48 nm. The Er3+-free glass sample containing AgCl exhibits surface plasmon resonance (SPR) band of Ag NPs centered at ~ 501 nm. From Judd-Ofelt analysis, it is found that by increasing the concentration of NPs, the value of O2 is enhanced suggesting increased covalency and decreased symmetry around the Er3+ ions. Integrated emission cross-section (IEC) is enhanced as the concentration of silver NPs is increased up to 0.5 mol% AgCl. Fourier infrared spectra show that the intensity of the vibrational band of the water molecule and fundamental stretching band of OH group are suppressed. Furthermore, under an excitation wavelength of 786 nm, three prominent upconversion emissions are observed at 520 nm, 550 nm and 650 nm which are attributed to 2H11/2, 4I15/2, 4S3/2, 4I15/2, and 4F9/2, 4I15/2 transitions, respectively. The upconversion emissions are enhanced significantly by introduction of silver NPs. The enhancement is mainly attributed to the local field effect of silver NPs. Studied nanocomposites are potential candidates for the development of solid state lasers

    Prevalence of Anaerobic Bacteria (P.gingivalis) as Major Microbial Agent in the Incidence Periodontal Diseases by Meta-analysis

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    Statement of the Problem: Periodontal diseases are complex oral diseases characterized by bacterial-induced inflammatory destruction of tooth-supporting tissues. Porphyromonas gingivalis (P. gingivalis) is a common gram-negative anaerobic oral bacteria strongly associated with periodontal disease. Purpose: The present study was conducted to estimate prevalence of P. gingivalis in patients with periodontal diseases by using meta-analysis method. Martials and Method: Different databases including PubMed, EmBase, Scopus, the Institute for Scientific Information (ISI) Web of Science, and the Cochrane Library were searched to identify original English-language studies addressing prevalence of P. gingivalis in periodontal diseases up to December 2014. The random effects model was applied in the meta-analysis and the heterogeneity between studies was assessed using a Cochran test and the I(2) index. Funnel plots and Egger test were used to examine publication bias. Statistical analyses were performed using STATA version 12. Results: Forty-two eligible studies published during 1993- 2016 were selected for meta-analysis. Considering all the included studies, the total sample size was 5,884 individuals containing 2,576 healthy people with a mean age of 37.21+/-7.45 years and 3,308 periodontal patients with a mean age of 44.16+/-8.35 years. Overall, the prevalence of P. gingivalis was 78 95% CI: 74-81 in periodontal diseases group and 34% 95% CI: 26-41 in healthy individuals. There was a significantly higher prevalence of P.gingivalis in individuals with periodontal diseases compared to healthy subjects 78% versus 34%, respectively. Conclusion: This study indicates that P. gingivalis is highly present in subjects with periodontal diseases and it also appears in periodontally healthy people, although to a lesser extent. Thus, the presence of P. gingivalis increases the chance of periodontal disease and it can be considered as a main potential risk factor

    Effect of wet curing duration on long-term performance of concrete in tidal zone of marine environment

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    A proper initial curing is a very simple and inexpensive alternative to improve concrete cover quality and accordingly extend the service life of reinforced concrete structures exposed to aggressive species. A current study investigates the effect of wet curing duration on chloride penetration in plain and blended cement concretes which subjected to tidal exposure condition in south of Iran for 5 years. The results show that wet curing extension preserves concrete against high rate of chloride penetration at early ages and decreases the difference between initial and long-term diffusion coefficients due to improvement of concrete cover quality. But, as the length of exposure period to marine environment increased the effects of initial wet curing became less pronounced. Furthermore, a relationship is developed between wet curing time and diffusion coefficient at early ages and the effect of curing length on time-to-corrosion initiation of concrete is addressed.Peer reviewedCivil and Environmental Engineerin

    Up-conversion enhancement in Er 3 +-Ag co-doped zinc tellurite glass: Effect of heat treatment

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    The melt quenching method was used to synthesize the Ag 0 nanoparticles and Er 3 + ions co-doped zinc tellurite glass. The glasses were characterized by differential thermal analyzer, UV-VIS-IR absorption, photoluminescence spectroscopy and TEM imaging. Heat treatment at different annealing time intervals above the glass transition temperature was applied to reduce the Ag + ions to Ag 0 NPs. The influence of heat treatment on structural and optical properties is examined. Intense and broad up-conversion emissions of silver are recorded in the visible region. Up-conversion luminescence spectra revealed three major emission peaks at 520, 550 and 650 nm originating from 2H 11/2, 4S 3/2 and 4F 9/2 levels, respectively. An efficient enhancement in visible region is observed for samples containing silver NPs. The absorption plasmon peaks are evidenced around 560 and 594 nm. The effect of localized surface plasmon resonance and the energy transfer from the surface of silver NP to trivalent erbium ions are described as the sources of enhancement. © 2012 Elsevier B.V. All rights reserved
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