73 research outputs found

    One-Pot Green Synthesis and Bioapplication ofl-Arginine-Capped Superparamagnetic Fe3O4 Nanoparticles

    Get PDF
    Water-solublel-arginine-capped Fe3O4 nanoparticles were synthesized using a one-pot and green method. Nontoxic, renewable and inexpensive reagents including FeCl3,l-arginine, glycerol and water were chosen as raw materials. Fe3O4 nanoparticles show different dispersive states in acidic and alkaline solutions for the two distinct forms of surface bindingl-arginine. Powder X-ray diffraction and X-ray photoelectron spectroscopy were used to identify the structure of Fe3O4 nanocrystals. The products behave like superparamagnetism at room temperature with saturation magnetization of 49.9 emu g−1 and negligible remanence or coercivity. In the presence of 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride, the anti-chloramphenicol monoclonal antibodies were connected to thel-arginine-capped magnetite nanoparticles. The as-prepared conjugates could be used in immunomagnetic assay

    Interaction of the Coronavirus Infectious Bronchitis Virus Membrane Protein with β-Actin and Its Implication in Virion Assembly and Budding

    Get PDF
    Coronavirus M protein is an essential component of virion and plays pivotal roles in virion assembly, budding and maturation. The M protein is integrated into the viral envelope with three transmembrane domains flanked by a short amino-terminal ectodomain and a large carboxy-terminal endodomain. In this study, we showed co-purification of the M protein from coronavirus infectious bronchitis virus (IBV) with actin. To understand the cellular factors that may be involved in virion assembly, budding and maturation processes, IBV M was used as the bait in a yeast two-hybrid screen, resulting in the identification of β-actin as a potentially interacting partner. This interaction was subsequently confirmed by coimmunoprecipitation and immunofluorescence microscopy in mammalian cells, and mutation of amino acids A159 and K160 on the M protein abolished the interaction. Introduction of the A159-K160 mutation into an infectious IBV clone system blocks the infectivity of the clone, although viral RNA replication and subgenomic mRNA transcription were actively detected. Disruption of actin filaments with cell-permeable agent cytochalasin D at early stages of the infection cycle led to the detection of viral protein synthesis in infected cells but not release of virus particles to the cultured media. However, the same treatment at late stages of the infection cycle did not affect the release of virus particles to the media, suggesting that disruption of the actin filaments might block virion assembly and budding, but not release of the virus particles. This study reveals an essential function of actin in the replication cycle of coronavirus

    The RBP-Jκ Binding Sites within the RTA Promoter Regulate KSHV Latent Infection and Cell Proliferation

    Get PDF
    Kaposi's sarcoma-associated herpesvirus (KSHV) is tightly linked to at least two lymphoproliferative disorders, primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). However, the development of KSHV-mediated lymphoproliferative disease is not fully understood. Here, we generated two recombinant KSHV viruses deleted for the first RBP-Jκ binding site (RTA1st) and all three RBP-Jκ binding sites (RTAall) within the RTA promoter. Our results showed that RTA1st and RTAall recombinant viruses possess increased viral latency and a decreased capability for lytic replication in HEK 293 cells, enhancing colony formation and proliferation of infected cells. Furthermore, recombinant RTA1st and RTAall viruses showed greater infectivity in human peripheral blood mononuclear cells (PBMCs) relative to wt KSHV. Interestingly, KSHV BAC36 wt, RTA1st and RTAall recombinant viruses infected both T and B cells and all three viruses efficiently infected T and B cells in a time-dependent manner early after infection. Also, the capability of both RTA1st and RTAall recombinant viruses to infect CD19+ B cells was significantly enhanced. Surprisingly, RTA1st and RTAall recombinant viruses showed greater infectivity for CD3+ T cells up to 7 days. Furthermore, studies in Telomerase-immortalized human umbilical vein endothelial (TIVE) cells infected with KSHV corroborated our data that RTA1st and RTAall recombinant viruses have enhanced ability to persist in latently infected cells with increased proliferation. These recombinant viruses now provide a model to explore early stages of primary infection in human PBMCs and development of KSHV-associated lymphoproliferative diseases

    Persistent changes in spinal cord gene expression after recovery from inflammatory hyperalgesia: A preliminary study on pain memory

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Previous studies found that rats subjected to carrageenan injection develop hyperalgesia, and despite complete recovery in several days, they continue to have an enhanced hyperalgesic response to a new noxious challenge for more than 28d. The study's aim was to identify candidate genes that have a role in the formation of the long-term hyperalgesia-related imprint in the spinal cord. This objective was undertaken with the understanding that the long-lasting imprint of acute pain in the central nervous system may contribute to the transition of acute pain to chronicity.</p> <p>Results</p> <p>To analyze changes in gene expression when carrageenan-induced hyperalgesia has disappeared but propensity for the enhanced hyperalgesic response is still present, we determined the gene expression profile using oligo microarray in the lumbar part of the spinal cord in three groups of rats: 28d after carrageenan injection, 24h after injection (the peak of inflammation), and with no injection (control group). Out of 17,000 annotated genes, 356 were found to be differentially expressed compared with the control group at 28d, and 329 at 24h after carrageenan injection (both groups at p < 0.01). Among differentially expressed genes, 67 (39 in 28d group) were identified as being part of pain-related pathways, altered in different models of pain, or interacting with proteins involved in pain-related pathways. Using gene ontology (GO) classification, we have identified 3 functional classes deserving attention for possible association with pain memory: They are related to cell-to-cell interaction, synaptogenesis, and neurogenesis.</p> <p>Conclusion</p> <p>Despite recovery from inflammatory hyperalgesia, persistent changes in spinal cord gene expression may underlie the propensity for the enhanced hyperalgesic response. We suggest that lasting changes in expression of genes involved in the formation of new synapses and neurogenesis may contribute to the transition of acute pain to chronicity.</p

    Harnessing the potential of ligninolytic enzymes for lignocellulosic biomass pretreatment

    Get PDF
    Abundant lignocellulosic biomass from various industries provides a great potential feedstock for the production of value-added products such as biofuel, animal feed, and paper pulping. However, low yield of sugar obtained from lignocellulosic hydrolysate is usually due to the presence of lignin that acts as a protective barrier for cellulose and thus restricts the accessibility of the enzyme to work on the cellulosic component. This review focuses on the significance of biological pretreatment specifically using ligninolytic enzymes as an alternative method apart from the conventional physical and chemical pretreatment. Different modes of biological pretreatment are discussed in this paper which is based on (i) fungal pretreatment where fungi mycelia colonise and directly attack the substrate by releasing ligninolytic enzymes and (ii) enzymatic pretreatment using ligninolytic enzymes to counter the drawbacks of fungal pretreatment. This review also discusses the important factors of biological pretreatment using ligninolytic enzymes such as nature of the lignocellulosic biomass, pH, temperature, presence of mediator, oxygen, and surfactant during the biodelignification process

    Pan-cancer analysis of whole genomes

    Get PDF
    Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

    Epigenetic modulators as therapeutic targets in prostate cancer

    Get PDF
    Prostate cancer is one of the most common non-cutaneous malignancies among men worldwide. Epigenetic aberrations, including changes in DNA methylation patterns and/or histone modifications, are key drivers of prostate carcinogenesis. These epigenetic defects might be due to deregulated function and/or expression of the epigenetic machinery, affecting the expression of several important genes. Remarkably, epigenetic modifications are reversible and numerous compounds that target the epigenetic enzymes and regulatory proteins were reported to be effective in cancer growth control. In fact, some of these drugs are already being tested in clinical trials. This review discusses the most important epigenetic alterations in prostate cancer, highlighting the role of epigenetic modulating compounds in pre-clinical and clinical trials as potential therapeutic agents for prostate cancer management.info:eu-repo/semantics/publishedVersio
    corecore