1,919 research outputs found

    Removal of some organic dyes by hexane-extracted spent bleaching earth

    Get PDF
    The removal of some organic dyes from aqueous solution by hexane-extracted spent bleaching earth, a waste material from the palm oil industry, was investigated. It was noted that the material had better affinity for basic than acid dyes. Various parameters affecting the removal process were studied. These were pH, initial dye concentration, sorbent dosage, temperature and agitation rate in the batch process. Experimental data show that both the boundary layer and intraparticle diffusion effect play important roles in the rate of dye removal. Maximum sorption capacities for some basic and acid dyes studied compare favourably with those reported using other low-cost sorbents

    A neuronal death model: overexpression of neuronal intermediate filament protein peripherin in PC12 cells

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Abnormal accumulation of neuronal intermediate filament (IF) is a pathological indicator of some neurodegenerative disorders. However, the underlying neuropathological mechanisms of neuronal IF accumulation remain unclear. A stable clone established from PC12 cells overexpressing a GFP-Peripherin fusion protein (pEGFP-Peripherin) was constructed for determining the pathway involved in neurodegeneration by biochemical, cell biology, and electronic microscopy approaches. In addition, pharmacological approaches to preventing neuronal death were also examined.</p> <p>Results</p> <p>Results of this study showed that TUNEL positive reaction could be detected in pEGFP-Peripherin cells. Swollen mitochondria and endoplasmic reticulum (ER) were seen by electron microscopy in pEGFP-Peripherin cells on day 8 of nerve growth factor (NGF) treatment. Peripherin overexpression not only led to the formation of neuronal IF aggregate but also causes aberrant neuronal IF phosphorylation and mislocation. Western blots showed that calpain, caspase-12, caspase-9, and caspase-3 activity was upregulated. Furthermore, treatment with calpain inhibitor significantly inhibited cell death.</p> <p>Conclusions</p> <p>These results suggested that the cytoplasmic neuronal IF aggregate caused by peripherin overexpression may induce aberrant neuronal IF phosphorylation and mislocation subsequently trapped and indirectly damaged mitochondria and ER. We suggested that the activation of calpain, caspase-12, caspase-9, and caspase-3 were correlated to the dysfunction of the ER and mitochondria in our pEGFP-Peripherin cell model. The present study suggested that pEGFP-Peripherin cell clones could be a neuronal death model for future studies in neuronal IFs aggregate associated neurodegeneration.</p

    Effects of Ox-LDL on Macrophages NAD(P)H Autofluorescence Changes by Two-photon Microscopy

    Get PDF
    Ox-LDL uptakes by macrophage play a critical role in the happening of atherosclerosis. Because of its low damage on observed cells and better signal-to- background ratio, two-photon excitation fluorescence microscopy is used to observe NAD(P)H autofluorescence of macrophage under difference cultured conditions- bare cover glass, coated with fibronectin or poly-D-lysine. The results show that the optimal condition is fibronectin coated surface, on which, macrophages profile can be clearly identified on NAD(P)H autofluorescence images collected by two-photon microscopy. Moreover, different morphology and intensities of autofluorescence under different conditions were observed as well. In the future, effects of ox-LDL on macrophages will be investigated by purposed system to research etiology of atherosclerosis.Comment: Submitted on behalf of TIMA Editions (http://irevues.inist.fr/tima-editions

    The Relationships among Chinese Practicing Teachers ’ Epistemic Beliefs, Pedagogical Beliefs and Their Beliefs about the Use of ICT

    Get PDF
    This study aimed to investigate the relationships among practicing teachers ’ epistemic beliefs, pedagogical beliefs and their beliefs about the use of ICT through survey methodology. Participants were 396 high school practicing teachers from mainland China. The path analysis results analyzed via structural equation modelling technique indicated that the systemic relationships among these three types of beliefs were nested. Specifically, teachers ’ sophisticated beliefs about the source of knowledge were aligned with constructivist pedagogical beliefs and constructivist use of ICT, with one belief highly related to another
    corecore