341 research outputs found

    Recovery of Zn2+, Fe2+ and Mn2+ from Some Selected Edible Vegetables and Pumpkin using Modified Maize Cobs

    Get PDF
    This study reports on the pre-concentration of some essential trace elements from vegetables using modified maize cobs by sorption. This was enabled by some functional groups anchored within the chemical structure of the material. Modification was achieved by treating the dry powdered material with thionylchloride (SOCl2) which was dispersed in dimethylformaldehyde (DMF) then reacting with ethylenediamine air drying the resultant for 24 hours. The presence of the anchored group was confirmed by FT-IR and it was used for Batch sorption experiments. The effect of pH, concentration, and dosage on the adsorption of zinc, iron and manganese ion by the parent and modified materials were carried out. Using the optimal parameters, the modified material was used for the pre-concentration of the trace metal ions from solutions of some selected vegetables samples. Pre-concentration of nutrients from fermented samples showed significantly high levels than non-fermented samples. This new method of pre-concentrating metal ions shows promising results and can improve the nutrition value in the preparation of dietary supplements. The method is effective and is of low cost

    Peptide Ligands Incorporated into the Threefold Spike Capsid Domain to Re-Direct Gene Transduction of AAV8 and AAV9 In Vivo

    Get PDF
    Efficiency and specificity of viral vectors are vital issues in gene therapy. Insertion of peptide ligands into the adeno-associated viral (AAV) capsid at receptor binding sites can re-target AAV2-derived vectors to alternative cell types. Also, the use of serotypes AAV8 and -9 is more efficient than AAV2 for gene transfer to certain tissues in vivo. Consequently, re-targeting of these serotypes by ligand insertion could be a promising approach but has not been explored so far. Here, we generated AAV8 and -9 vectors displaying peptides in the threefold spike capsid domain. These peptides had been selected from peptide libraries displayed on capsids of AAV serotype 2 to optimize systemic gene delivery to murine lung tissue and to breast cancer tissue in PymT transgenic mice (PymT). Such peptide insertions at position 590 of the AAV8 capsid and position 589 of the AAV9 capsid changed the transduction properties of both serotypes. However, both peptides inserted in AAV8 did not result in the same changes of tissue tropism as they did in AAV2. While the AAV2 peptides selected on murine lung tissue did not alter tropism of serotypes 8 and -9, insertion of the AAV2-derived peptide selected on breast cancer tissue augmented tumor gene delivery in both serotypes. Further, this peptide mediated a strong but unspecific in vivo gene transfer for AAV8 and abrogated transduction of various control tissues for AAV9. Our findings indicate that peptide insertion into defined sites of AAV8 and -9 capsids can change and improve their efficiency and specificity compared to their wild type variants and to AAV2, making these insertion sites attractive for the generation of novel targeted vectors in these serotypes

    A complex of α(6) integrin and E-cadherin drives liver metastasis of colorectal cancer cells through hepatic angiopoietin-like 6.

    Get PDF
    Homing of colorectal cancer (CRC) cells to the liver is a non-random process driven by a crosstalk between tumour cells and components of the host tissue. Here we report the isolation of a liver metastasis-specific peptide ligand (CGIYRLRSC) that binds a complex of E-cadherin and α(6) integrin on the surface of CRC cells. We identify angiopoietin-like 6 protein as a peptide-mimicked natural ligand enriched in hepatic blood vessels of CRC patients. We demonstrate that an interaction between hepatic angiopoietin-like 6 and tumoural α(6) integrin/E-cadherin drives liver homing and colonization by CRC cells, and that CGIYRLRSC inhibits liver metastasis through interference with this ligand/receptor system. Our results indicate a mechanism for metastasis whereby a soluble factor accumulated in normal vessels functions as a specific ligand for circulating cancer cells. Consistently, we show that high amounts of coexpressed α(6) integrin and E-cadherin in primary tumours represent a poor prognostic factor for patients with advanced CRC

    A Ligand Peptide Motif Selected from a Cancer Patient Is a Receptor-Interacting Site within Human Interleukin-11

    Get PDF
    Interleukin-11 (IL-11) is a pleiotropic cytokine approved by the FDA against chemotherapy-induced thrombocytopenia. From a combinatorial selection in a cancer patient, we isolated an IL-11-like peptide mapping to domain I of the IL-11 (sequence CGRRAGGSC). Although this motif has ligand attributes, it is not within the previously characterized interacting sites. Here we design and validate in-tandem binding assays, site-directed mutagenesis and NMR spectroscopy to show (i) the peptide mimics a receptor-binding site within IL-11, (ii) the binding of CGRRAGGSC to the IL-11Rα is functionally relevant, (iii) Arg4 and Ser8 are the key residues mediating the interaction, and (iv) the IL-11-like motif induces cell proliferation through STAT3 activation. These structural and functional results uncover an as yet unrecognized receptor-binding site in human IL-11. Given that IL-11Rα has been proposed as a target in human cancer, our results provide clues for the rational design of targeted drugs
    • …
    corecore