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Brian C. Nairn Nadia R. Azar Janessa D.M. Drake 《Journal of electromyography and kinesiology》2013,23(6):1421-1427
BackgroundSitting is a commonly adopted posture during work and prolonged exposures may have detrimental effects. Little attention has been paid to the thoracic spine and/or multiple axes of motion during prolonged sitting. Accordingly, this study examined three-dimensional motion and muscle activity of the trunk during two hours of uninterrupted sitting.MethodsTen asymptomatic males sat during a simulated office task. Kinematics were analyzed from six segments (Neck, Upper-, Mid-, and Lower-thoracic, Lumbar, and Pelvis) and electromyography was recorded from eight muscles bilaterally.ResultsFour participants developed transient pain. These participants showed higher average muscle activations in the abdominal muscles. Additionally, the non-pain group showed less lateral bend positional change in the mid-thoracic region compared to the upper- and lower-thoracic regions. Weak-to-moderate positive correlations were also found between rated pain and low back muscle activation.DiscussionThe results provided further evidence of reduced movement in non-pain developers and altered muscle activation patterns in pain developers. Low-level, prolonged static contractions could lead to an increased risk of injury; and though the increased abdominal activity in the pain developers was not directly associated with increased rated pain scores, this could indicate a pre-disposition to, or enhancer of, transient pain development. 相似文献
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Djaber Tazdaït Nadia Abdi Hakim Lounici Hocine Grib Nabil Mameri André Pauss 《Bioremediation Journal》2013,17(4):294-304
Acclimated activated sludge was examined for its ability to degrade malathion with and without the presence of glucose as a potential cometabolite substrate. In this study, a packed-bed reactor (PBR) using three kinds of biofilm carriers was employed for efficient degradation of malathion. The results obtained indicate that microorganisms tested were able to degrade malathion. The observed degradation rate of the pesticide in the presence of glucose was the same as without glucose. The activated sludge was found to be able to use malathion as the sole phosphorus source. In contrast, the degradation ability of the activated sludge was lost when the pesticide was used as the sole source of sulfur. The degradation capacity of the PBR was higher than the performance obtained with the batch reactor. The reactor packed with crushed olive kernels exhibited the best performance, allowing a total removal of malathion (10 mg/dm3) within 12 h. 相似文献
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Galal E. H. Elgemeie Omar A. Mansour Nadia H. Metwally 《Nucleosides, nucleotides & nucleic acids》2013,32(1):113-123
Abstract A series of different novel nonclassical nucleosides have been synthesised and evaluated for their inhibitory activity against human immunodeficiency virus (HIV) replication in MT-4 cells. 相似文献
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Ei Ei Min Bijoyita Roy Nadia Amrani Feng He Allan Jacobson 《RNA (New York, N.Y.)》2013,19(8):1105-1115
The central nonsense-mediated mRNA decay (NMD) regulator, Upf1, selectively targets nonsense-containing mRNAs for rapid degradation. In yeast, Upf1 preferentially associates with mRNAs that are NMD substrates, but the mechanism of its selective retention on these mRNAs has yet to be elucidated. Previously, we demonstrated that Upf1 associates with 40S ribosomal subunits. Here, we define more precisely the nature of this association using conventional and affinity-based purification of ribosomal subunits, and a two-hybrid screen to identify Upf1-interacting ribosomal proteins. Upf1 coimmunoprecipitates specifically with epitope-tagged 40S ribosomal subunits, and Upf1 association with high-salt washed or puromycin-released 40S subunits was found to occur without simultaneous eRF1, eRF3, Upf2, or Upf3 association. Two-hybrid analyses and in vitro binding assays identified a specific interaction between Upf1 and Rps26. Using mutations in domains of UPF1 known to be crucial for its function, we found that Upf1:40S association is modulated by ATP, and Upf1:Rps26 interaction is dependent on the N-terminal Upf1 CH domain. The specific association of Upf1 with the 40S subunit is consistent with the notion that this RNA helicase not only triggers rapid decay of nonsense-containing mRNAs, but may also have an important role in dissociation of the premature termination complex. 相似文献
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Ingrid Kikkas Roberto Mallone Nadia Tubiana-Rufi Didier Chevenne Jean Claude Carel Christophe Créminon Hervé Volland Christian Boitard Nathalie Morel 《PloS one》2013,8(7)
Type 1 diabetes (T1D) is an autoimmune disease which results from the destruction of pancreatic beta cells. Autoantibodies directed against islet antigens are valuable diagnostic tools. Insulin autoantibodies (IAAs) are usually the first to appear and also the most difficult to detect amongst the four major islet autoantibodies. A non-radioactive IAA bridging ELISA was developed to this end. In this assay, one site of the IAAs from serum samples is bound to a hapten-labeled insulin (GC300-insulin), which is subsequently captured on anti-GC300 antibody-coated 96-well plates. The other site of the IAAs is bound to biotinylated insulin, allowing the complex to be detected by an enzyme-streptavidin conjugate. In the present study, 50 serum samples from patients with newly diagnosed T1D and 100 control sera from non-diabetic individuals were analyzed with our new assay and the results were correlated with an IAA radioimmunoassay (RIA). Using IAA bridging ELISA, IAAs were detected in 32 out of 50 T1D children, whereas with IAA RIA, 41 out of 50 children with newly diagnosed T1D were scored as positive. In conclusion, the IAA bridging ELISA could serve as an attractive approach for rapid and automated detection of IAAs in T1D patients for diagnostic purposes. 相似文献
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Nadia Lamari Maria Valeria Ruggiero Giuliana d’Ippolito Wiebe H. C. F. Kooistra Angelo Fontana Marina Montresor 《PloS one》2013,8(8)
Oxylipins are low-molecular weight secondary metabolites derived from the incorporation of oxygen into the carbon chains of polyunsaturated fatty acids (PUFAs). Oxylipins are produced in many prokaryotic and eukaryotic lineages where they are involved in a broad spectrum of actions spanning from stress and defense responses, regulation of growth and development, signaling, and innate immunity. We explored the diversity in oxylipin patterns in the marine planktonic diatom Pseudo-nitzschia. This genus includes several species only distinguishable with the aid of molecular markers. Oxylipin profiles of cultured strains were obtained by reverse phase column on a liquid chromatograph equipped with UV photodiode detector and q-ToF mass spectrometer. Lipoxygenase compounds were mapped on phylogenies of the genus Pseudo-nitzschia inferred from the nuclear encoded hyper-variable region of the LSU rDNA and the plastid encoded rbcL. Results showed that the genus Pseudo-nitzschia exhibits a rich and varied lipoxygenase metabolism of eicosapentaenoic acid (EPA), with a high level of specificity for oxylipin markers that generally corroborated the genotypic delineation, even among genetically closely related cryptic species. These results suggest that oxylipin profiles constitute additional identification tools for Pseudo-nitzschia species providing a functional support to species delineation obtained with molecular markers and morphological traits. The exploration of the diversity, patterns and plasticity of oxylipin production across diatom species and genera will also provide insights on the ecological functions of these secondary metabolites and on the selective pressures driving their diversification. 相似文献