University of Valencia

About: University of Valencia is a education organization based out in Valencia, Spain. It is known for research contribution in the topics: Population & Neutrino. The organization has 27096 authors who have published 65669 publications receiving 1765689 citations. The organization is also known as: Universitat de València & UV.

Extracellular Vesicles from Parasitic Helminths Contain Specific Excretory/Secretory Proteins and Are Internalized in Intestinal Host Cells

Abstract: The study of host-parasite interactions has increased considerably in the last decades, with many studies focusing on the identification of parasite molecules (ie surface or excretory/secretory proteins (ESP)) as potential targets for new specific treatments and/or diagnostic tools In parallel, in the last few years there have been significant advances in the field of extracellular vesicles research Among these vesicles, exosomes of endocytic origin, with a characteristic size ranging from 30–100 nm, carry several atypical secreted proteins in different organisms, including parasitic protozoa Here, we present experimental evidence for the existence of exosome-like vesicles in parasitic helminths, specifically the trematodes Echinostoma caproni and Fasciola hepatica These microvesicles are actively released by the parasites and are taken up by host cells Trematode extracellular vesicles contain most of the proteins previously identified as components of ESP, as confirmed by proteomic, immunogold labeling and electron microscopy studies In addition to parasitic proteins, we also identify host proteins in these structures The existence of extracellular vesicles explains the secretion of atypical proteins in trematodes, and the demonstration of their uptake by host cells suggests an important role for these structures in host-parasite communication, as described for other infectious agents

Cell lines: a tool for in vitro drug metabolism studies.

Abstract: Primary cultured hepatocytes are a valuable in vitro model for drug metabolism studies. However, their widespread use is greatly hindered by the scarcity of suitable human liver samples. Moreover, the well-known in vitro phenotypic instability of hepatocytes, the irregular availability of fresh human liver for cell harvesting purposes, and the high batch-to-batch functional variability of hepatocyte preparations obtained from different human liver donors, seriously complicate their use in routine testing. To overcome these limitations, different cell line models have been proposed for drug metabolism screening. Human liver-derived cell lines would be ideal models for this purpose given their availability, unlimited life-span, stable phenotype, and the fact that they are easy to handle. However, the human hepatoma cells currently used (i.e. HepG2, Mz-Hep-1) show negligible levels of drug-metabolizing and do not constitute a real alternative to primary hepatocytes. Different strategies have been proposed to generate metabolically competent immortalized hepatocytes (transformation of human hepatocytes with plasmids encoding immortalizing genes, hepatocyte-like cells derived from stem cells, cell lines generated from transgenic animals, hepatocyte/hepatoma hydrid cells). Moreover, recombinant models heterologously expressing P450 enzymes in different host cells have been developed and successfully used in drug metabolism testing. In addition, new strategies have recently been explored to upregulate the expression of drug-metabolizing enzymes in cell lines of a human origin (i.e. transfection with expression vectors encoding key hepatic transcription factors). Among metabolic-based drug-drug interactions, P450 inhibition seems to be the most important. A major application of recombinant models expressing a single P450 is the screening of potential enzyme inhibitors. Therefore, pharmaceutical companies increasingly make use of cell lines to speed up the selection of new drugs with favourable pharmacokinetic and metabolic properties.

High proton conduction in a chiral ferromagnetic metal-organic quartz-like framework.

Abstract: A complex-as-ligand strategy to get a multifunctional molecular material led to a metal–organic framework with the formula (NH4)4[MnCr2(ox)6]·4H2O. Single-crystal X-ray diffraction revealed that the anionic bimetallic coordination network adopts a chiral three-dimensional quartz-like architecture. It hosts ammonium cations and water molecules in functionalized channels. In addition to ferromagnetic ordering below TC = 3.0 K related to the host network, the material exhibits a very high proton conductivity of 1.1 × 10–3 S cm–1 at room temperature due to the guest molecules.