94 research outputs found

    African swine fever virus assembles a single membrane derived from rupture of the endoplasmic reticulum

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    Collective evidence argues that two members of the nucleocytoplasmic large DNA viruses (NCLDVs) acquire their membrane from open membrane intermediates, postulated to be derived from membrane rupture. We now study membrane acquisition of the NCLDV African swine fever virus. By electron tomography (ET), the virion assembles a single bilayer, derived from open membrane precursors that collect as ribbons in the cytoplasm. Biochemically, lumenal endoplasmic reticulum (ER) proteins are released into the cytosol, arguing that the open intermediates are ruptured ER membranes. ET shows that viral capsid assembles on the convex side of the open viral membrane to shape it into an icosahedron. The viral capsid is composed of tiny spikes with a diameter of ∌5nm, connected to the membrane by a 6nm wide structure displaying thin striations, as observed by several complementary electron microscopy imaging methods. Immature particles display an opening that closes after uptake of the viral genome and core proteins, followed by the formation of the mature virion. Together with our previous data, this study shows a common principle of NCLDVs to build a single internal envelope from open membrane intermediates. Our data now provide biochemical evidence that these open intermediates result from rupture of a cellular membrane, the ER. © 2015 John WileyDeutsche Forschungsgemeinschaft personal grant KR2173 to Jacomine Krijnse Locker. German Andres is supported by the ‘Amarouto Program for senior scientists from the Comunidad AutĂłnoma de Madrid’ and by grants BFU2009-08085 and AGL2013-48998-C2- 2-R from the Spanish Ministerio de EconomĂ­a y CompetitividadPeer Reviewe

    Specific effects of bortezomib against experimental malignant pleural effusion: a preclinical study

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    BACKGROUND: We have previously shown that nuclear factor (NF)-ÎșB activation of mouse Lewis lung carcinoma (LLC) specifically promotes the induction of malignant pleural effusions (MPE) by these cells. In the present studies we hypothesized that treatment of immunocompetent mice with bortezomib tailored to inhibit cancer cell NF-ÎșB activation and not proliferation specifically inhibits MPE formation by LLC cells. RESULTS: Treatment of LLC cells with low concentrations of bortezomib (100 ng/ml) inhibited NF-ÎșB activation and NF-ÎșB-dependent transcription, but not cellular proliferation. Bortezomib treatment of immunocompetent C57BL/6 mice bearing LLC-induced subcutaneous tumors and MPEs significantly blocked tumor-specific NF-ÎșB activation. However, bortezomib treatment did not impair subcutaneous LLC tumor growth, but was effective in limiting LLC-induced MPE. This specific effect was evidenced by significant reductions in effusion accumulation and the associated mortality and was observed with both preventive (beginning before MPE formation) and therapeutic (beginning after MPE establishment) bortezomib treatment. The favorable impact of bortezomib on MPE was associated with suppression of cardinal MPE-associated phenomena, such as inflammation, vascular hyperpermeability, and angiogenesis. In this regard, therapeutic bortezomib treatment had identical favorable results on MPE compared with preventive treatment, indicating that the drug specifically counteracts effusion formation. CONCLUSIONS: These studies indicate that proteasome inhibition tailored to block NF-ÎșB activation of lung adenocarcinoma specifically targets the effusion-inducing phenotype of this tumor. Although the drug has limited activity against advanced solid lung cancer, it may prove beneficial for patients with MPE

    Role of Vanadium in Cellular and Molecular Immunology: Association with Immune-Related Inflammation and Pharmacotoxicology Mechanisms

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    Over the last decade, a diverse spectrum of vanadium compounds has arisen as anti-inflammatory therapeutic metallodrugs targeting various diseases. Recent studies have demonstrated that select well-defined vanadium species are involved in many immune-driven molecular mechanisms that regulate and influence immune responses. In addition, advances in cell immunotherapy have relied on the use of metallodrugs to create a “safe,” highly regulated, environment for optimal control of immune response. Emerging findings include optimal regulation of B/T cell signaling and expression of immune suppressive or anti-inflammatory cytokines, critical for immune cell effector functions. Furthermore, in-depth perusals have explored NF-ÎșB and Toll-like receptor signaling mechanisms in order to enhance adaptive immune responses and promote recruitment or conversion of inflammatory cells to immunodeficient tissues. Consequently, well-defined vanadium metallodrugs, poised to access and resensitize the immune microenvironment, interact with various biomolecular targets, such as B cells, T cells, interleukin markers, and transcription factors, thereby influencing and affecting immune signaling. A synthetically formulated and structure-based (bio)chemical reactivity account of vanadoforms emerges as a plausible strategy for designing drugs characterized by selectivity and specificity, with respect to the cellular molecular targets intimately linked to immune responses, thereby giving rise to a challenging field linked to the development of immune system vanadodrugs

    Safety of alginate\u2010konjac\u2010xanthan polysaccharide complex (PGX) as a novel food pursuant to Regulation (EC) No\ua0258/97

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    Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver a scientific opinion on alginate-konjac- xanthan polysaccharide complex (PGX) as a novel food (NF) submitted pursuant to Regulation (EC) No 258/97. The NF is an off-white granular powder composed of three non- starch polysaccharides: konjac glucomannan, xanthan gum and sodium alginate. The information provided on the composition, the specifications, the batch-to-batch variability and the stability of the NF is sufficient and does not raise safety concerns. The production process is sufficiently described and does not raise concerns about the safety of the NF. The applicant intends to add the NF to a variety of foods as well as to market the NF in capsules. The recommended maximum daily intake of the NF from fortified foods and food supplements is 15 g. The target population proposed by the applicant is adults from 18 to 64 years of age. Considering the no observed adverse effect level of 1.8 g/kg body weight (bw) per day in a subchronic toxicity study with PGX and the highest mean and 95th percentile anticipated daily intake of NF from fortified foods, the margin of exposure (MoE) is 12 and 6, respectively, whereas the MoE for the NF from food supplements is 9. The Panel concludes that the safety of the novel food, PGX, for the intended uses and use levels as proposed by the applicant, has not been established. (C) 2017 European Food Safety Authority

    Safety of proline-specific oligopeptidase as a novel food pursuant to Regulation (EC) No 258/97

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    Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on proline-specific oligopeptidase (Tolerase (R) G) as a novel food ingredient submitted pursuant to Regulation (EC) No 258/97 of the European Parliament and of the Council, taking into account the comments and objections of a scientific nature raised by Member States. The novel food is an enzyme preparation of prolyl-oligopeptidase produced with a genetically modified Aspergillus niger self clone strain. The target population is the general adult population. The results from a bacterial reverse mutation test and of an in vitro chromosome aberration test did not indicate genotoxicity. The Panel considers that the reported effects observed in a 90-day rat study are treatment-related effects and can be attributed to the higher energy consumption by these animals. Taking into account the intended maximum use level for Tolerase (R) G, its daily consumption would correspond to 2,746 mg TOS/person or to 39.2 mg TOS/kg body weight (bw) per day, when considering a default body weight of 70 kg for an adult person. The margin between this value and the dose in the rats, which caused effects attributable to the excess energy intake, is approximately 45. Noting this margin, the Panel considers that it is unlikely that such effects would occur in human at the intended use levels. The Panel concludes that the NF, Tolerase (R) G, is safe for the intended use at the intended use level. (C) 2017 European Food Safety Authority.Peer reviewe

    Scientific Opinion on taxifolin‐rich extract from Dahurian Larch (Larix gmelinii)

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    Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to carry out the additional assessment for taxifolin-rich extract from Dahurian Larch as a food ingredient in the context of Regulation (EC) No 258/97. The novel food (NF) is a taxifolin-rich water\u2013ethanol extract from the wood of the Dahurian Larch and contains a minimum of 90% taxifolin. The Panel considers that the taxifolin-rich extract is sufficiently characterised and that its compositional data and specifications do not raise safety concerns. The NF is intended to be added to non-alcoholic beverages, to yogurt and to chocolate confectionery. The Panel considers that the data on genotoxicity do not raise concern. In a subchronic rat study performed in accordance with OECD standards, the highest dose tested (i.e. 1,500 mg/kg bw) was considered to be the NOAEL. The margin of exposure (MOE) of the combined intake (158 mg) from the intended food uses (including 100 mg from food supplements) would result to about 660 for an adult weighing 70 kg. For adolescents, taking into account a default body weight of 45 kg, the MOE of the combined intake (146 mg) would be about 460. In the absence of a high percentile intake estimate for children between 9 and 14 years of age, the Panel considers the P97.5 intake estimate from the intended food uses (except from food supplements) for children between 10 and 17 years, i.e. 46 mg/day. Taking into account a default body weight of 29.4 kg (P5 body weight for children aged 10\u201314 years as suggested by EFSA Scientific Committee (2012)), the resulting MOE would be about 960

    Imaging in situ breast carcinoma (with or without an invasive component) with technetium-99m pentavalent dimercaptosuccinic acid and technetium-99m 2-methoxy isobutyl isonitrile scintimammography

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    INTRODUCTION: The aim of the study was to retrospectively define specific features of the technetium-99m pentavalent dimercaptosuccinic acid ((99m)Tc-(V)DMSA) and technetium-99m 2-methoxy isobutyl isonitrile ((99m)Tc-Sestamibi [(99m)Tc-MIBI]) distribution in ductal breast carcinoma in situ and lobular breast carcinoma in situ (DCIS/LCIS), in relation to mammographic, histological and immunohistochemical parameters. MATERIALS AND METHODS: One hundred and two patients with suspicious palpation or mammographic findings were submitted preoperatively to scintimammography (a total of 72 patients with (99m)Tc-(V)DMSA and a total of 75 patients with (99m)Tc-Sestamibi, 45 patients receiving both radiotracers). Images were acquired at 10 min and 60 min, and were evaluated for a pattern of diffuse radiotracer accumulation. The tumor-to-background ratios were correlated (T-pair test) with mammographic, histological and immunohistochemical characteristics. RESULTS: Histology confirmed malignancy in 46/102 patients: 20/46 patients had DCIS/LCIS, with or without coexistent invasive lesions, and 26/46 patients had isolated invasive carcinomas. Diffuse (99m)Tc-(V)DMSA accumulation was noticed in 18/19 cases and (99m)Tc-Sestamibi in 6/13 DCIS/LCIS cases. Epithelial hyperplasia demonstrated a similar accumulation pattern. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value for each tracer were calculated. Solely for (99m)Tc-(V)DMSA, the tumor-to-background ratio was significantly higher at 60 min than at 10 min and the diffuse uptake was significantly associated with suspicious microcalcifications, with the cell proliferation index ≄ 40% and with c-erbB-2 ≄ 10%. CONCLUSION: (99m)Tc-(V)DMSA showed high sensitivity and (99m)Tc-Sestamibi showed high specificity in detecting in situ breast carcinoma ((99m)Tc-(V)DMSA especially in cases with increased cell proliferation), and these radiotracers could provide clinicians with preoperative information not always obtainable by mammography

    The Genome of the Netherlands: Design, and project goals

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    Within the Netherlands a national network of biobanks has been established (Biobanking and Biomolecular Research Infrastructure-Netherlands (BBMRI-NL)) as a national node of the European BBMRI. One of the aims of BBMRI-NL is to enrich biobanks with different types of molecular and phenotype data. Here, we describe the Genome of the Netherlands (GoNL), one of the projects within BBMRI-NL. GoNL is a whole-genome-sequencing project in a representative sample consisting of 250 trio-families from all provinces in the Netherlands, which aims to characterize DNA sequence variation in the Dutch population. The parent-offspring trios include adult individuals ranging in age from 19 to 87 years (mean=53 years; SD=16 years) from birth cohorts 1910-1994. Sequencing was done on blood-derived DNA from uncultured cells and accomplished coverage was 14-15x. The family-based design represents a unique resource to assess the frequency of regional variants, accurately reconstruct haplotypes by family-based phasing, characterize short indels and complex structural variants, and establish the rate of de novo mutational events. GoNL will also serve as a reference panel for imputation in the available genome-wide association studies in Dutch and other cohorts to refine association signals and uncover population-specific variants. GoNL will create a catalog of human genetic variation in this sample that is uniquely characterized with respect to micro-geographic location and a wide range of phenotypes. The resource will be made available to the research and medical community to guide the interpretation of sequencing projects. The present paper summarizes the global characteristics of the project
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