48 research outputs found

    Effect of pruning-derived biochar on heavy metals removal and water dynamics

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    Biomass-derived biochar is considered as a promising heavy metal adsorbent, due to abundance of polar functional groups, such as carboxylic, hydroxyl, and amino groups, which are available for heavy metal removal. The aims of this study were to evaluate the effectiveness of an orchard pruning-derived biochar in removing some heavy metals (through the evaluation of isotherms) and to study water dynamics at the solid-liquid interface as affected by heavy metal adsorption (through an innovative nuclear magnetic resonance (NMR) relaxometry approach). Both isotherms and NMR spectra revealed that Pb and Cr showed a good affinity for the biochar surface (Pb > Cr), while Cu was less affine. Accordingly, higher amounts of Pb and Cr were adsorbed by biochar as compared to those of Cu in the single systems. In binary systems (i.e., when two metals were applied simultaneously), Pb showed the highest inhibition of the adsorption of the other two metals, whereas the opposite was evidenced when Cu was used; the competitive adsorption was also strongly influenced by the metal residence time on biochar surface. In ternary systems (i.e., when all metals were applied simultaneously), even in the presence of high amounts of Pb and Cr, considerable adsorption of Cu occurred, indicating that some biochar adsorption sites were highly specific for a single metal

    Identification and characterization of a novel non-structural protein of bluetongue virus

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    Bluetongue virus (BTV) is the causative agent of a major disease of livestock (bluetongue). For over two decades, it has been widely accepted that the 10 segments of the dsRNA genome of BTV encode for 7 structural and 3 non-structural proteins. The non-structural proteins (NS1, NS2, NS3/NS3a) play different key roles during the viral replication cycle. In this study we show that BTV expresses a fourth non-structural protein (that we designated NS4) encoded by an open reading frame in segment 9 overlapping the open reading frame encoding VP6. NS4 is 77–79 amino acid residues in length and highly conserved among several BTV serotypes/strains. NS4 was expressed early post-infection and localized in the nucleoli of BTV infected cells. By reverse genetics, we showed that NS4 is dispensable for BTV replication in vitro, both in mammalian and insect cells, and does not affect viral virulence in murine models of bluetongue infection. Interestingly, NS4 conferred a replication advantage to BTV-8, but not to BTV-1, in cells in an interferon (IFN)-induced antiviral state. However, the BTV-1 NS4 conferred a replication advantage both to a BTV-8 reassortant containing the entire segment 9 of BTV-1 and to a BTV-8 mutant with the NS4 identical to the homologous BTV-1 protein. Collectively, this study suggests that NS4 plays an important role in virus-host interaction and is one of the mechanisms played, at least by BTV-8, to counteract the antiviral response of the host. In addition, the distinct nucleolar localization of NS4, being expressed by a virus that replicates exclusively in the cytoplasm, offers new avenues to investigate the multiple roles played by the nucleolus in the biology of the cell

    Prostatic sarcoma after treatment of rectal cancer

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    <p>Abstract</p> <p>Background</p> <p>The relationship between radiation exposure for treatment of cancer and occurrence of a second primary cancer at the irradiated site is well known. This phenomenon is however rare in prostate.</p> <p>Case presentation</p> <p>A 75-year-old farmer was treated for rectal cancer with preoperative 45 Gy of radiotherapy and abdominoperineal resection. Four years later he developed symptoms of bladder outlet obstruction and acute urinary retention. He underwent a transurethral resection of the prostate. Histological examination of the removed prostate tissue and immunohistochemistry revealed it to be a poorly differentiated sarcoma.</p> <p>Conclusion</p> <p>We believe this to be the first reported case of radiation-induced sarcoma following radiotherapy treatment for rectal cancer. Since radiotherapy plays a pivotal role in the contemporary treatment of rectal adenocarcinoma, it is relevant to be aware of the potential long-term carcinogenic complications of radiotherapy of the pelvis.</p

    Information Transmission in Cercal Giant Interneurons Is Unaffected by Axonal Conduction Noise

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    What are the fundamental constraints on the precision and accuracy with which nervous systems can process information? One constraint must reflect the intrinsic “noisiness” of the mechanisms that transmit information between nerve cells. Most neurons transmit information through the probabilistic generation and propagation of spikes along axons, and recent modeling studies suggest that noise from spike propagation might pose a significant constraint on the rate at which information could be transmitted between neurons. However, the magnitude and functional significance of this noise source in actual cells remains poorly understood. We measured variability in conduction time along the axons of identified neurons in the cercal sensory system of the cricket Acheta domesticus, and used information theory to calculate the effects of this variability on sensory coding. We found that the variability in spike propagation speed is not large enough to constrain the accuracy of neural encoding in this system

    Agrifood authentication and traceability by soil-based indicators.

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    Agrifood authentication and traceability by soil-based indicators

    EFFECT OF METALS ON THE DYNAMICS OF WATER AT THE BIOCHAR SOLID-LIQUID INTERFACE

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    Previous studies revealed that water molecules are hooked to biochar surfaces through unconventional hydrogen bonds (De Pasquale et al., 2012; Conte et al., 2013). Next question to answer is how metals can affect water mobility as they are adsorbed on biochar surface. To this aim, an orchard pruning char obtained by pyrolysis at 500°C was treated with solutions of Cu(II), Cr(VI) and Cu(II)+Cr(VI). Two different types of water can be recognized in BC. Namely, a fast relaxing water (T1 = 99 ms) is differentiated by a slow relaxing one (T 1= 233 ms). The former is made by molecules interacting with biochar surface through formation of the unconventional Hbonds previously identified (De Pasquale et al., 2012; Conte et al., 2013). The latter is made by water molecules freely slipping on the immobilized water layer. After metal adsorption, no changes were observed in MTBC relaxogram shapes as compared to BC relaxogram (Fig. 1). Moreover, all the MTBC relaxograms were similar to each other, regardless of the metal adsorbed on the carbonaceous material. Nature of the metal appears not to affect water dynamics on the porous material. The shortening of the T 1values in MTBC as compared to BC sample (from 99 to 42 ms, and from 23 to 95 ms, respectively) has been interpreted by two different molecular models. In the first case, a water layer may be immobilized on the metals directly adsorbed on MTBC surface (Fig. 2A). Since metal-water interactionscan be stronger than those in the untreated BC, the result is a shortening of the T1values from 99 to 40 ms. As a consequence, also the H-bonds between the immobilized water and the freely moving one can be strengthened, thereby leading to shorter T 1 value. The second molecular model considers metal ions bridging two water layers (Fig. 2B). The first water layer is immobilized directly on the surface of the porous material and it is bridged to the second water layer through the metal cation. Further investigations are needed in order to differentiate among the different models accounting for water dynamics on the surface of biochar treated with metal cations
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