254 research outputs found

    Health impact of nanotechnologies in food production

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    Geen RIVM rapportnummer in publicatieInventory study on the current use of nanotechnology in food products and advise on the most relevant safety evaluation issues. This report describes the results of this study. The report is set up in two parts. First you will find an aggregation of the results in the answer to 10 questions. In this part you will also find our suggestions for prioritizing the research that is needed. The second document is a scientific background document

    The P2X(7) receptor tracer [C-11]SMW139 as an in vivo marker of neuroinflammation in multiple sclerosis: a first-in man study

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    Purpose: The novel PET tracer [11C]SMW139 binds with high affinity to the P2X7 receptor, which is expressed on pro-inflammatory microglia. The purposes of this first in-man study were to characterise pharmacokinetics of [11C]SMW139 in patients with active relapsing remitting multiple sclerosis (RRMS) and healthy controls (HC) and to evaluate its potential to identify in vivo neuroinflammation in RRMS. / Methods: Five RRMS patients and 5 age-matched HC underwent 90-min dynamic [11C]SMW139 PET scans, with online continuous and manual arterial sampling to generate a metabolite-corrected arterial plasma input function. Tissue time activity curves were fitted to single- and two-tissue compartment models, and the model that provided the best fits was determined using the Akaike information criterion. / Results: The optimal model for describing [11C]SMW139 kinetics in both RRMS and HC was a reversible two-tissue compartment model with blood volume parameter and with the dissociation rate k4 fixed to the whole-brain value. Exploratory group level comparisons demonstrated an increased volume of distribution (VT) and binding potential (BPND) in RRMS compared with HC in normal appearing brain regions. BPND in MS lesions was decreased compared with non-lesional white matter, and a further decrease was observed in gadolinium-enhancing lesions. In contrast, increased VT was observed in enhancing lesions, possibly resulting from disruption of the blood-brain barrier in active MS lesions. In addition, there was a high correlation between parameters obtained from 60- to 90-min datasets, although analyses using 60-min data led to a slight underestimation in regional VT and BPND values. / Conclusions: This first in-man study demonstrated that uptake of [11C]SMW139 can be quantified with PET using BPND as a measure for specific binding in healthy controls and RRMS patients. Additional studies are warranted for further clinical evaluation of this novel neuroinflammation tracer

    Health impact of nanotechnologies in food production

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    Geen RIVM rapportnummer in publicatieInventory study on the current use of nanotechnology in food products and advise on the most relevant safety evaluation issues. This report describes the results of this study. The report is set up in two parts. First you will find an aggregation of the results in the answer to 10 questions. In this part you will also find our suggestions for prioritizing the research that is needed. The second document is a scientific background document

    The heat-pipe resembling action of boiling bubbles in endovenous laser ablation

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    Endovenous laser ablation (EVLA) produces boiling bubbles emerging from pores within the hot fiber tip and traveling over a distal length of about 20 mm before condensing. This evaporation-condensation mechanism makes the vein act like a heat pipe, where very efficient heat transport maintains a constant temperature, the saturation temperature of 100°C, over the volume where these non-condensing bubbles exist. During EVLA the above-mentioned observations indicate that a venous cylindrical volume with a length of about 20 mm is kept at 100°C. Pullback velocities of a few mm/s then cause at least the upper part of the treated vein wall to remain close to 100°C for a time sufficient to cause irreversible injury. In conclusion, we propose that the mechanism of action of boiling bubbles during EVLA is an efficient heat-pipe resembling way of heating of the vein wall

    Cannabidiol causes activated hepatic stellate cell death through a mechanism of endoplasmic reticulum stress-induced apoptosis

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    The major cellular event in the development and progression of liver fibrosis is the activation of hepatic stellate cells (HSCs). Activated HSCs proliferate and produce excess collagen, leading to accumulation of scar matrix and fibrotic liver. As such, the induction of activated HSC death has been proposed as a means to achieve resolution of liver fibrosis. Here we demonstrate that cannabidiol (CBD), a major non-psychoactive component of the plant Cannabis sativa, induces apoptosis in activated HSCs through a cannabinoid receptor-independent mechanism. CBD elicits an endoplasmic reticulum (ER) stress response, characterized by changes in ER morphology and the initiation of RNA-dependent protein kinase-like ER kinase-, activating transcription factor-6-, and inositol-requiring ER-to-nucleus signal kinase-1 (IRE1)-mediated signaling cascades. Furthermore, CBD induces downstream activation of the pro-apoptotic IRE1/ASK1/c-Jun N-terminal kinase pathway, leading to HSC death. Importantly, we show that this mechanism of CBD-induced ER stress-mediated apoptosis is specific to activated HSCs, as it occurs in activated human and rat HSC lines, and in primary in vivo-activated mouse HSCs, but not in quiescent HSCs or primary hepatocytes from rat. Finally, we provide evidence that the elevated basal level of ER stress in activated HSCs has a role in their susceptibility to the pro-apoptotic effect of CBD. We propose that CBD, by selectively inducing death of activated HSCs, represents a potential therapeutic agent for the treatment of liver fibrosis

    A proposed new bacteriophage subfamily: “Jerseyvirinae”

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    © 2015, Springer-Verlag Wien. Based on morphology and comparative nucleotide and protein sequence analysis, a new subfamily of the family Siphoviridae is proposed, named “Jerseyvirinae” and consisting of three genera, “Jerseylikevirus”, “Sp3unalikevirus” and “K1glikevirus”. To date, this subfamily consists of 18 phages for which the genomes have been sequenced. Salmonella phages Jersey, vB_SenS_AG11, vB_SenS-Ent1, vB_SenS-Ent2, vB_SenS-Ent3, FSL SP-101, SETP3, SETP7, SETP13, SE2, SS3e and wksl3 form the proposed genus “Jerseylikevirus”. The proposed genus “K1glikevirus” consists of Escherichia phages K1G, K1H, K1ind1, K1ind2 and K1ind3. The proposed genus “Sp3unalikevirus” contains one member so far. Jersey-like phages appear to be widely distributed, as the above phages were isolated in the UK, Canada, the USA and South Korea between 1970 and the present day. The distinguishing features of this subfamily include a distinct siphovirus morphotype, genomes of 40.7-43.6kb (49.6-51.4mol% G+C), a syntenic genome organisation, and a high degree of nucleotide sequence identity and shared proteins. All known members of the proposed subfamily are strictly lytic

    S100A7 and the progression of breast cancer

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    The S100 gene family comprises more than 20 members whose protein sequences encompass at least one EF-hand Ca(2+ )binding motif. The expression of individual family members is not ubiquitous for all tissues and there appears to be an element of tissue-specific expression. Molecular analysis of breast tumors has revealed that several S100s, including S100A2, S100A4 and S100A7, exhibit altered expression levels during breast tumorigenesis and/or progression. Subsequent studies have started to describe a functional role for these S100 proteins as well as their mechanism of action and the biochemical pathways they modify. The present review outlines what is known about S100A7 in breast cancer and summarizes the need to better understand the importance of this protein in breast cancer

    A Shigella boydii bacteriophage which resembles Salmonella phage ViI

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    <p>Abstract</p> <p>Background</p> <p>Lytic bacteriophages have been applied successfully to control the growth of various foodborne pathogens. Sequencing of their genomes is considered as an important preliminary step to ensure their safety prior to food applications.</p> <p>Results</p> <p>The lytic bacteriophage, ΦSboM-AG3, targets the important foodborne pathogen, <it>Shigella</it>. It is morphologically similar to phage ViI of <it>Salmonella enterica </it>serovar Typhi and a series of phages of <it>Acinetobacter calcoaceticus </it>and <it>Rhizobium meliloti</it>. The complete genome of ΦSboM-AG3 was determined to be 158 kb and was terminally redundant and circularly permuted. Two hundred and sixteen open reading frames (ORFs) were identified and annotated, most of which displayed homology to proteins of <it>Salmonella </it>phage ViI. The genome also included four genes specifying tRNAs.</p> <p>Conclusions</p> <p>This is the first time that a Vi-specific phage for <it>Shigella </it>has been described. There is no evidence for the presence of virulence and lysogeny-associated genes. In conclusion, the genome analysis of ΦSboM-AG3 indicates that this phage can be safely used for biocontrol purposes.</p
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