31 results on '"Kass, GEN"'
Search Results
2. Reduced Atherosclerosis in Dietary Copper-Supplemented Cholesterol-Fed Rabbits is Associated with Fewer Smooth Muscle Cells and Decreased Apoptosis
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Lamb, DJ, primary, Avades, TY, additional, Papachristou, S, additional, Anwar, K, additional, Kass, GEN, additional, and Ferns, GAA, additional
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- 2001
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3. Guidance on the scientific requirements for an application for authorisation of a novel food in the context of Regulation (EU) 2015/2283.
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Turck D, Bohn T, Castenmiller J, de Henauw S, Hirsch-Ernst KI, Maciuk A, Mangelsdorf I, McArdle HJ, Naska A, Pentieva K, Siani A, Thies F, Tsabouri S, Vinceti M, Aguilera Gómez M, Cubadda F, Frenzel T, Heinonen M, Neuhäuser-Berthold M, Peláez C, Poulsen M, Prieto Maradona M, Schlatter JR, Siskos A, van Loveren H, Ackerl R, Albert O, Azzollini D, Fernández Dumont A, Gelbmann W, Germini A, Glymenaki M, Kass GEN, Kouloura E, Laganaro M, Matijevic L, Mendes V, Noriega Fernández E, Nuin Garciarena I, Precup G, Roldán Torres R, Rossi A, Turla E, Valtueña Martinez S, Ververis E, and Knutsen HK
- Abstract
The European Commission requested EFSA to update the scientific guidance for the preparation of applications for authorisation of novel foods, previously developed following the adoption of Regulation (EU) 2015/2283 on novel foods. This guidance document provides advice on the scientific information needed to be submitted by the applicant towards demonstrating the safety of the novel food. Requirements pertain to the description of the novel food, production process, compositional data, specifications, proposed uses and use levels and anticipated intake of the novel food. Furthermore, information needed in sections on the history of use of the novel food and/or its source, absorption, distribution, metabolism, excretion, toxicological information, nutritional information and allergenicity is also described. The applicant should integrate and interpret the data presented in the different sections to provide their overall considerations on how the information supports the safety of the novel food under the proposed conditions of use. Where potential health hazards have been identified, they are to be discussed in relation to the anticipated intake of the novel food and the proposed target populations. On the basis of the information provided, EFSA will assess the safety of the novel food under the proposed conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
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- 2024
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4. TKPlate 1.0: An Open-access platform for toxicokinetic and toxicodynamic modelling of chemicals to implement new approach methodologies in chemical risk assessment.
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Dorne JLCM, Cortiñas-Abrahantes J, Spyropoulos F, Darney K, Lautz L, Louisse J, Kass GEN, Carnesecchi E, Liem AKD, Tarazona JV, Billat PA, Beaudoin R, Zeman F, Bodin C, Smith A, Nathanail A, Di Nicola MR, Kleiner J, Terron A, Parra-Morte JM, Verloo D, and Robinson T
- Abstract
This publication is linked to the following EFSA Supporting Publications articles: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2023.EN-8441/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2023.EN-8440/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2023.EN-8437/full., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2023 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
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- 2023
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5. New approach methodologies in human regulatory toxicology - Not if, but how and when!
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Schmeisser S, Miccoli A, von Bergen M, Berggren E, Braeuning A, Busch W, Desaintes C, Gourmelon A, Grafström R, Harrill J, Hartung T, Herzler M, Kass GEN, Kleinstreuer N, Leist M, Luijten M, Marx-Stoelting P, Poetz O, van Ravenzwaay B, Roggeband R, Rogiers V, Roth A, Sanders P, Thomas RS, Marie Vinggaard A, Vinken M, van de Water B, Luch A, and Tralau T
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- Humans, Reproducibility of Results, Risk Assessment methods, Artificial Intelligence, Toxicity Tests methods
- Abstract
The predominantly animal-centric approach of chemical safety assessment has increasingly come under pressure. Society is questioning overall performance, sustainability, continued relevance for human health risk assessment and ethics of this system, demanding a change of paradigm. At the same time, the scientific toolbox used for risk assessment is continuously enriched by the development of "New Approach Methodologies" (NAMs). While this term does not define the age or the state of readiness of the innovation, it covers a wide range of methods, including quantitative structure-activity relationship (QSAR) predictions, high-throughput screening (HTS) bioassays, omics applications, cell cultures, organoids, microphysiological systems (MPS), machine learning models and artificial intelligence (AI). In addition to promising faster and more efficient toxicity testing, NAMs have the potential to fundamentally transform today's regulatory work by allowing more human-relevant decision-making in terms of both hazard and exposure assessment. Yet, several obstacles hamper a broader application of NAMs in current regulatory risk assessment. Constraints in addressing repeated-dose toxicity, with particular reference to the chronic toxicity, and hesitance from relevant stakeholders, are major challenges for the implementation of NAMs in a broader context. Moreover, issues regarding predictivity, reproducibility and quantification need to be addressed and regulatory and legislative frameworks need to be adapted to NAMs. The conceptual perspective presented here has its focus on hazard assessment and is grounded on the main findings and conclusions from a symposium and workshop held in Berlin in November 2021. It intends to provide further insights into how NAMs can be gradually integrated into chemical risk assessment aimed at protection of human health, until eventually the current paradigm is replaced by an animal-free "Next Generation Risk Assessment" (NGRA)., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Roland Grafstroem reports a relationship with Predictomics AB that includes: equity or stocks. Rob Roggeband reports a relationship with The European Partnership for Alternative Approaches to Animal Testing that includes: board membership. Thomas Hartung reports a relationship with Underwriters Laboratories (UL) that includes: consulting or advisory. Thomas Hartung reports a relationship with ToxTrack LLC that includes: consulting or advisory and equity or stocks. Thomas Hartung reports a relationship with AxoSim that includes: consulting or advisory and equity or stocks. Roland Grafstroem has patent #Patent US10556323B2 and Patent EP3149204 licensed to Licensee. Thomas Hartung has patent licensed to Licensee. All other authors declare no competing interests., (Copyright © 2023 German Federal Institute for Risk Assessment. Published by Elsevier Ltd.. All rights reserved.)
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- 2023
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6. Nrf2-Mediated Pathway Activated by Prunus spinosa L. (Rosaceae) Fruit Extract: Bioinformatics Analyses and Experimental Validation.
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Colomba M, Benedetti S, Fraternale D, Guidarelli A, Coppari S, Freschi V, Crinelli R, Kass GEN, Gorassini A, Verardo G, Roselli C, Meli MA, Di Giacomo B, and Albertini MC
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- Fruit chemistry, Plant Extracts chemistry, Plant Extracts pharmacology, Computational Biology, Humans, U937 Cells, Antioxidants pharmacology, Prunus chemistry, Signal Transduction drug effects
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In our previous studies, Prunus spinosa fruit (PSF) ethanol extract was showed to exert antioxidant, antimicrobial, anti-inflammatory and wound healing activities. In the present study, an integrated bioinformatics analysis combined with experimental validation was carried out to investigate the biological mechanism(s) that are responsible for the reported PSF beneficial effects as an antioxidant during a pro-inflammatory TLR4 insult. Bioinformatics analysis using miRNet 2.0 was carried out to address which biological process(es) the extract could be involved in. In addition, Chemprop was employed to identify the key targets of nuclear receptor (NR) signaling and stress response (SR) pathways potentially modulated. The miRNet analysis suggested that the PSF extract mostly activates the biological process of cellular senescence. The Chemprop analysis predicted three possible targets for nine phytochemicals found in the extract: (i) ARE signaling, (ii) mitochondrial membrane potential (MMP) and (iii) p53 SR pathways. The PSF extract antioxidant effect was also experimentally validated in vitro using the human monocyte U937 cell line. Our findings showed that Nrf2 is modulated by the extract with a consequent reduction of the oxidative stress level. This was confirmed by a strong decrease in the amount of reactive oxygen species (ROS) observed in the PSF-treated cells subjected to lipopolysaccharide (LPS) (6 h treatment, 1 µg/mL). No visible effects were observed on p53 and MMP modulation., Competing Interests: The authors declare no conflicts of interest. The views and opinions expressed in this manuscript do not represent those of EFSA.
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- 2023
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7. Re-evaluation of the existing health-based guidance values for copper and exposure assessment from all sources.
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More SJ, Bampidis V, Benford D, Bragard C, Halldorsson TI, Hernández-Jerez AF, Bennekou SH, Koutsoumanis K, Lambré C, Machera K, Mullins E, Nielsen SS, Schlatter JR, Schrenk D, Turck D, Younes M, Boon P, Ferns GA, Lindtner O, Smolders E, Wilks M, Bastaki M, de Sesmaisons-Lecarré A, Ferreira L, Greco L, Kass GEN, Riolo F, and Leblanc JC
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Copper is an essential micronutrient and also a regulated product used in organic and in conventional farming pest management. Both deficiency and excessive exposure to copper can have adverse health effects. In this Scientific Opinion, the EFSA 2021 harmonised approach for establishing health-based guidance values (HBGVs) for substances that are regulated products and also nutrients was used to resolve the divergent existing HBGVs for copper. The tightly regulated homeostasis prevents toxicity manifestation in the short term, but the development of chronic copper toxicity is dependent on copper homeostasis and its tissue retention. Evidence from Wilson disease suggests that hepatic retention is indicative of potential future and possibly sudden onset of copper toxicity under conditions of continuous intake. Hence, emphasis was placed on copper retention as an early marker of potential adverse effects. The relationships between (a) chronic copper exposure and its retention in the body, particularly the liver, and (b) hepatic copper concentrations and evidence of toxicity were examined. The Scientific Committee (SC) concludes that no retention of copper is expected to occur with intake of 5 mg/day and established an Acceptable Daily Intake (ADI) of 0.07 mg/kg bw. A refined dietary exposure assessment was performed, assessing contribution from dietary and non-dietary sources. Background copper levels are a significant source of copper. The contribution of copper from its use as plant protection product (PPP), food and feed additives or fertilisers is negligible. The use of copper in fertilisers or PPPs contributes to copper accumulation in soil. Infant formula and follow-on formula are important contributors to dietary exposure of copper in infants and toddlers. Contribution from non-oral sources is negligible. Dietary exposure to total copper does not exceed the HBGV in adolescents, adults, elderly and the very elderly. Neither hepatic copper retention nor adverse effects are expected to occur from the estimated copper exposure in children due to higher nutrient requirements related to growth., (© 2023 Wiley‐VCH Verlag GmbH & Co. KgaA on behalf of the European Food Safety Authority.)
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- 2023
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8. Risk Assessment of Combined Exposure to Multiple Chemicals at the European Food Safety Authority: Principles, Guidance Documents, Applications and Future Challenges.
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Cattaneo I, Kalian AD, Di Nicola MR, Dujardin B, Levorato S, Mohimont L, Nathanail AV, Carnessechi E, Astuto MC, Tarazona JV, Kass GEN, Liem AKD, Robinson T, Manini P, Hogstrand C, Price PS, and Dorne JLCM
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- Animals, Humans, European Union, Risk Assessment methods, Forecasting, Food Safety methods, Animal Feed analysis
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Human health and animal health risk assessment of combined exposure to multiple chemicals use the same steps as single-substance risk assessment, namely problem formulation, exposure assessment, hazard assessment and risk characterisation. The main unique feature of combined RA is the assessment of combined exposure, toxicity and risk. Recently, the Scientific Committee of the European Food Safety Authority (EFSA) published two relevant guidance documents. The first one "Harmonised methodologies for the human health, animal health and ecological risk assessment of combined exposure to multiple chemicals" provides principles and explores methodologies for all steps of risk assessment together with a reporting table. This guidance supports also the default assumption that dose addition is applied for combined toxicity of the chemicals unless evidence for response addition or interactions (antagonism or synergism) is available. The second guidance document provides an account of the scientific criteria to group chemicals in assessment groups using hazard-driven criteria and prioritisation methods, i.e., exposure-driven and risk-based approaches. This manuscript describes such principles, provides a brief description of EFSA's guidance documents, examples of applications in the human health and animal health area and concludes with a discussion on future challenges in this field.
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- 2023
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9. Use of New Approach Methodologies (NAMs) in regulatory decisions for chemical safety: Report from an EPAA Deep Dive Workshop.
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Westmoreland C, Bender HJ, Doe JE, Jacobs MN, Kass GEN, Madia F, Mahony C, Manou I, Maxwell G, Prieto P, Roggeband R, Sobanski T, Schütte K, Worth AP, Zvonar Z, and Cronin MTD
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- Animals, European Union, Humans, Industry, Risk Assessment, Animal Testing Alternatives, Toxicity Tests methods
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New Approach Methodologies (NAMs) are considered to include any in vitro, in silico or chemistry-based method, as well as the strategies to implement them, that may provide information that could inform chemical safety assessment. Current chemical legislation in the European Union is limited in its acceptance of the widespread use of NAMs. The European Partnership for Alternative Approaches to Animal Testing (EPAA) therefore convened a 'Deep Dive Workshop' to explore the use of NAMs in chemical safety assessment, the aim of which was to support regulatory decisions, whilst intending to protect human health. The workshop recognised that NAMs are currently used in many industrial sectors, with some considered as fit for regulatory purpose. Moreover, the workshop identified key discussion points that can be addressed to increase the use and regulatory acceptance of NAMs. These are based on the changes needed in frameworks for regulatory requirements and the essential needs in education, training and greater stakeholder engagement as well the gaps in the scientific basis of NAMs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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10. Cardiotoxicity of Chemical Substances: An Emerging Hazard Class.
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Georgiadis N, Tsarouhas K, Dorne JCM, Kass GEN, Laspa P, Toutouzas K, Koulaouzidou EA, Kouretas D, and Tsitsimpikou C
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(1) Background: Human health risks and hazards from chemical substances are well regulated internationally. However, cardiotoxicity, is not defined as a stand-alone hazard and therefore there are no defined criteria for the classification of substances as cardiotoxic. Identifying and regulating substances that cause cardiovascular adverse effects would undoubtedly strengthen the national health systems. (2) Methods: To overcome the aforementioned gap, a roadmap is proposed for identifying regulatory criteria from animal studies and endorse legislation in order to classify substances as cardiotoxic. The roadmap consists of: (i) the identification of the appropriate animal species and strains; (ii) the identification of the lines of scientific evidence (e.g., histopathological, biochemical and echocardiographic indices etc.) from animal studies with relevance to humans; (iii) the statistical analysis and meta-analysis for each line of scientific evidence after exposure to well-established cardiotoxicants to humans (e.g., anthracyclines) in order to identify threshold values or range of normal and/ or altered values due to exposure; (iv) validation of the above described lines of evidence in animals exposed to other alleged cardiotoxic substances (e.g., anabolic androgen steroids (AAS) and pesticides); (v) establishment of mechanisms of action based on information of either known or alleged cardiotoxicants; and (vi) introduction of novel indices and in silico methods. (3) Results: Preliminary results in rats indicate a clear distinction from normal values to values measured in rats exposed to anthracyclines regarding left ventricle (LV) fractional shortening (FS) and LV ejection fraction (EF). A distinctive pattern is similarly observed for Creatine Kinase-Myocardial Band isoenzyme (CK-MB) and cardiac tissue glutathione (GSH). These findings are encouraging and indicate that there is room for targeted research to this end, and that these specific indices and biochemical markers should be further investigated in order to be developed to regulatory criteria. (4) Conclusions: Further research should be conducted by both the scientific and regulatory community that aims to clearly define the cardiotoxicity hazard caused by chemicals and develop a full set of scientific criteria.
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- 2022
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11. In Silico Methods for Environmental Risk Assessment: Principles, Tiered Approaches, Applications, and Future Perspectives.
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Astuto MC, Di Nicola MR, Tarazona JV, Rortais A, Devos Y, Liem AKD, Kass GEN, Bastaki M, Schoonjans R, Maggiore A, Charles S, Ratier A, Lopes C, Gestin O, Robinson T, Williams A, Kramer N, Carnesecchi E, and Dorne JCM
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- Computer Simulation, Quantitative Structure-Activity Relationship, Risk Assessment, Ecosystem, Ecotoxicology
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This chapter aims to introduce the reader to the basic principles of environmental risk assessment of chemicals and highlights the usefulness of tiered approaches within weight of evidence approaches in relation to problem formulation i.e., data availability, time and resource availability. In silico models are then introduced and include quantitative structure-activity relationship (QSAR) models, which support filling data gaps when no chemical property or ecotoxicological data are available. In addition, biologically-based models can be applied in more data rich situations and these include generic or species-specific models such as toxicokinetic-toxicodynamic models, dynamic energy budget models, physiologically based models, and models for ecosystem hazard assessment i.e. species sensitivity distributions and ultimately for landscape assessment i.e. landscape-based modeling approaches. Throughout this chapter, particular attention is given to provide practical examples supporting the application of such in silico models in real-world settings. Future perspectives are discussed to address environmental risk assessment in a more holistic manner particularly for relevant complex questions, such as the risk assessment of multiple stressors and the development of harmonized approaches to ultimately quantify the relative contribution and impact of single chemicals, multiple chemicals and multiple stressors on living organisms., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2022
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12. Vipers of Major clinical relevance in Europe: Taxonomy, venom composition, toxicology and clinical management of human bites.
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Di Nicola MR, Pontara A, Kass GEN, Kramer NI, Avella I, Pampena R, Mercuri SR, Dorne JLCM, and Paolino G
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- Animals, Classification methods, Disease Management, Europe epidemiology, Humans, Snake Bites epidemiology, Antivenins therapeutic use, Snake Bites classification, Snake Bites drug therapy, Viper Venoms classification, Viper Venoms toxicity, Viperidae classification
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Snakebites in Europe are mostly due to bites from Viperidae species of the genus Vipera. This represents a neglected public health hazard with poorly defined incidence, morbidity and mortality. In Europe, fourteen species of "true vipers" (subfamily Viperinae) are present, eleven of which belong to the genus Vipera. Amongst these, the main medically relevant species due to their greater diffusion across Europe and the highest number of registered snakebites are six, namely: Vipera ammodytes, V. aspis, V. berus, V. latastei, V. seoanei and V. ursinii. Generally speaking, viper venom composition is characterised by many different toxin families, like phospholipases A2, snake venom serine proteases, snake venom metalloproteases, cysteine-rich secretory proteins, C-type lectins, disintegrins, haemorrhagic factors and coagulation inhibitors. A suspected snakebite is often associated with severe pain, erythema, oedema and, subsequently, the onset of an ecchymotic area around one or two visible fang marks. In the field, the affected limb should be immobilised and mildly compressed with a bandage, which can then be removed once the patient is being treated in hospital. The clinician should advise the patient to remain calm to reduce blood circulation and, therefore, decrease the spread of the toxins. In the case of pain, an analgesic therapy can be administered, the affected area can be treated with hydrogen peroxide or clean water. However, anti-inflammatory drugs and disinfection with alcohol or alcoholic substances should be avoided. For each patient, clinical chemistry and ECG are always a pre-requisite as well as the evaluation of the tetanus immunisation status and for which immunisation may be provided if needed. The treatment of any clinical complication, due to the envenomation, does not differ from treatments of emergency nature. Antivenom is recommended when signs of systemic envenomation exist or in case of advanced local or systemic progressive symptoms. Recommendations for future work concludes. The aim of this review is to support clinicians for the clinical management of viper envenomation, through taxonomic keys for main species identification, description of venom composition and mode of action of known toxins and provide a standardised clinical protocol and antivenom administration., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2021
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13. Application of the Threshold of Toxicological Concern (TTC) in Food Safety: Challenges and Opportunities.
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Serafimova R, Coja T, and Kass GEN
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The safety assessment of chemicals added or found in food has traditionally made use of data from in vivo studies performed on experimental animals. The nature and amount of data required to carry out a risk assessment is generally stipulated either in the different food legislations or in sectoral guidance documents. However, there are still cases where no or only limited experimental data are available or not specified by law, for example for contaminants or for some minor metabolites from active substances in plant protection products. For such cases, the Threshold of Toxicological Concern (TTC) can be applied. This review explores the use of the TTC approach in food safety in the European Union, in relation to the different food sectors, legal requirements and future opportunities., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Serafimova, Coja and Kass.)
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- 2021
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14. EFSA's OpenFoodTox: An open source toxicological database on chemicals in food and feed and its future developments.
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Dorne JLCM, Richardson J, Livaniou A, Carnesecchi E, Ceriani L, Baldin R, Kovarich S, Pavan M, Saouter E, Biganzoli F, Pasinato L, Zare Jeddi M, Robinson TP, Kass GEN, Liem AKD, Toropov AA, Toropova AP, Yang C, Tarkhov A, Georgiadis N, Di Nicola MR, Mostrag A, Verhagen H, Roncaglioni A, Benfenati E, and Bassan A
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- Animals, Databases, Factual, Humans, Quantitative Structure-Activity Relationship, Risk Assessment, Food, Food Safety
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Since its creation in 2002, the European Food Safety Authority (EFSA) has produced risk assessments for over 5000 substances in >2000 Scientific Opinions, Statements and Conclusions through the work of its Scientific Panels, Units and Scientific Committee. OpenFoodTox is an open source toxicological database, available both for download and data visualisation which provides data for all substances evaluated by EFSA including substance characterisation, links to EFSA's outputs, applicable legislations regulations, and a summary of hazard identification and hazard characterisation data for human health, animal health and ecological assessments. The database has been structured using OECD harmonised templates for reporting chemical test summaries (OHTs) to facilitate data sharing with stakeholders with an interest in chemical risk assessment, such as sister agencies, international scientific advisory bodies, and others. This manuscript provides a description of OpenFoodTox including data model, content and tools to download and search the database. Examples of applications of OpenFoodTox in chemical risk assessment are discussed including new quantitative structure-activity relationship (QSAR) models, integration into tools (OECD QSAR Toolbox and AMBIT-2.0), assessment of environmental footprints and testing of threshold of toxicological concern (TTC) values for food related compounds. Finally, future developments for OpenFoodTox 2.0 include the integration of new properties, such as physico-chemical properties, exposure data, toxicokinetic information; and the future integration within in silico modelling platforms such as QSAR models and physiologically-based kinetic models. Such structured in vivo, in vitro and in silico hazard data provide different lines of evidence which can be assembled, weighed and integrated using harmonised Weight of Evidence approaches to support the use of New Approach Methodologies (NAMs) in chemical risk assessment and the reduction of animal testing., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2021
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15. [Corrigendum] What is considered cardiotoxicity of anthracyclines in animal studies.
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Georgiadis N, Tsarouhas K, Rezaee R, Nepka H, Kass GEN, Dorne JCM, Stagos D, Toutouzas K, Spandidos DA, Kouretas D, and Tsitsimpikou C
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Subsequently to the publication of this paper, the authors have realized that the name of the seventh listed author, Dimitrios Stagos, was spelt incorrectly (it appeared as 'Stagkos' in print). The corrected author list is shown above. The authors regret that the name of the seventh author on the paper was spelt incorrectly, and apologize to the readers for any inconvenience caused.[the original article was published in Oncology Reports 44: 798-818, 2020; DOI: 10.3892/or.2020.7688].
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- 2020
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16. What is considered cardiotoxicity of anthracyclines in animal studies.
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Georgiadis N, Tsarouhas K, Rezaee R, Nepka H, Kass GEN, Dorne JCM, Stagkos D, Toutouzas K, Spandidos DA, Kouretas D, and Tsitsimpikou C
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- Animals, Cardiotoxicity etiology, Echocardiography standards, Models, Animal, Rats, Toxicity Tests methods, Anthracyclines toxicity, Antibiotics, Antineoplastic toxicity, Cardiotoxicity diagnosis, Guidelines as Topic, Toxicity Tests standards
- Abstract
Anthracyclines are commonly used anticancer drugs with well‑known and extensively studied cardiotoxic effects in humans. In the clinical setting guidelines for assessing cardiotoxicity are well‑established with important therapeutic implications. Cardiotoxicity in terms of impairment of cardiac function is largely diagnosed by echocardiography and based on objective metrics of cardiac function. Until this day, cardiotoxicity is not an endpoint in the current general toxicology and safety pharmacology preclinical studies, although other classes of drugs apart from anthracyclines, along with everyday chemicals have been shown to manifest cardiotoxic properties. Also, in the relevant literature there are not well‑established objective criteria or reference values in order to uniformly characterize cardiotoxic adverse effects in animal models. This in depth review focuses on the evaluation of two important echocardiographic indices, namely ejection fraction and fractional shortening, in the literature concerning anthracycline administration to rats as the reference laboratory animal model. The analysis of the gathered data gives promising results and solid prospects for both, defining anthracycline cardiotoxicity objective values and delineating the guidelines for assessing cardiotoxicity as a separate hazard class in animal preclinical studies for regulatory purposes.
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- 2020
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17. Letter to the editor regarding the article 'EFSA's toxicological assessment of aspartame: was it even-handedly trying to identify possible unreliable positives and unreliable negatives?'
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Kass GEN and Lodi F
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This letter is in response to a recent paper by Millstone and Dawson (2019) in which the authors criticise the re-evaluation of the high intensity sweetener aspartame in 2013 by the former EFSA's Panel on Food Additives and Nutrient Sources added to Food, on the grounds that EFSA did not follow its own procedures for its risk assessment. Moreover, the authors claim that the appraisal of the available studies was asymmetrically more alert to putative false positives than to possible false negatives. In this letter it is shown that the methodology for collection and selection of the scientific information used as a basis for the aspartame risk assessment, and the inclusion/exclusion criteria applied were defined a priori and documented in the published opinion. Furthermore, the Panel applied a Weight-of-Evidence approach combined with an analysis of the biological relevance of the appraised and validated evidence for its analysis, integration and interpretation, followed by an uncertainty analysis. Finally, an analysis of the distribution of negative versus positive outcome of the studies in the context of reliability showed that the claim of bias in the scientific risk assessment of aspartame is not substantiated., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2020.)
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- 2020
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18. Potential emerging chemical risks in the food chain associated with substances registered under REACH.
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Oltmanns J, Licht O, Bohlen ML, Schwarz M, Escher SE, Silano V, MacLeod M, Noteborn HPJM, Kass GEN, and Merten C
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- Biodegradation, Environmental, Humans, Pilot Projects, Risk Assessment, Environmental Pollutants, Food Chain, Hazardous Substances
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A screening procedure for the identification of potential emerging chemical risks in the food and feed chain developed in a previous EFSA-sponsored pilot study was applied to 15021 substances registered under the REACH Regulation at the time of evaluation. Eligible substances were selected from this dataset by excluding (a) intermediates handled under strictly controlled conditions, (b) substances lacking crucial input data and (c) compounds considered to be outside the applicability domain of the models used. Selection of eligible substances resulted in a considerable reduction to 2336 substances. These substances were assessed and scored for environmental release (tonnage and use information from REACH registration dossiers), biodegradation (predictions from BIOWIN models 3, 5 and 6 evaluated in a battery approach), bioaccumulation in food/feed (ACC-HUMANsteady modelling) and chronic human health hazards (classification according to the CLP Regulation for carcinogenicity, mutagenicity, reproductive toxicity and repeated dose toxicity as well as IARC classification for carcinogenicity). Prioritisation based on the scores assigned and additional data curation steps identified 212 substances that are considered potential emerging risks in the food chain. Overall, 53% of these substances were prioritised due to chronic hazards identified in REACH registrations dossiers only (i.e. hazards not identified in classifications from other sources). Bioaccumulation in food and feed predicted on the basis of ACC-HUMANsteady modelling identified many substances that are not considered bioaccumulative in aquatic or terrestrial organisms based on screening criteria of the relevant ECHA guidance documents. Furthermore, 52% of the priority substances have not yet been assessed for their presence in food/feed by EU regulatory agencies. This finding and illustrative examples suggest that the screening procedure identified substances that have the potential to be emerging chemical risks in the food chain. Future research should investigate whether they actually represent emerging chemical risks as defined in EFSA's mandate.
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- 2020
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19. A Summary Report of FSCJ Workshop "Future Challenges and Opportunities in Developing Methodologies for Improved Human Risk Assessments".
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Tachibana K, Kass GEN, Ono A, Yamada T, Tong W, Doerge DR, and Yamazoe Y
- Abstract
This is a summary report of FSCJ (Food Safety Commission of Japan) workshop entitled "Future Challenges and Opportunities in Developing Methodologies for Improved Human Risk Assessments, which held in November 2018. Scientific advancements have facilitated the development of new methods for chemical risk assessments with the expansion of toxicological databases. They are promising tools to overcome challenges, such as situations of data insufficiency, estimation of internal exposure and prediction of hazard, and enable us to improve our human health risk assessment in food safety. In this review, current understandings on developments in chemical risk assessments, especially focusing on Threshold of Toxicological Concern (TTC) approach, non-testing and in-silico approaches (e.g. read-across), and physiologically based pharmacokinetics (PBPK) modeling are discussed as possible promising tools. It also discusses future challenges and opportunities regarding social environment buildings in which all stakeholders including scientific experts, risk managers and consumers are able to accept these new risk assessment technologies. International collaboration would increase and enhance the efficiency in forming innovative ideas and in translating them into regulatory practices. It would strengthen technical capacity of experts who contribute to regulatory decisions and also promote acceptance of new methodologies among stakeholders. Cross-sectional collaboration such as making good use of human data of pharmaceutical drugs will facilitate a development of fresh tools for food safety domains. Once a new methodology is recognized in risk assessment agencies as implementable, it needs to be acknowledged and accepted by wider range of different stakeholders. Such stakeholders include scientific experts who conduct risk assessment for the risk assessment agencies, food industries and consumers. Transparency in the risk assessment work performed by regulatory agencies should strengthen their credibility and promote the acceptance of risk assessment including the new methodologies used in it. At the same time, efforts should be continued by regulatory agencies to further communicate with consumers about the concept of risk-based assessment as well as the concept of uncertainty., Competing Interests: Conflict of interest statement: The authors had no conflicts of interest to declare in this article. Disclaimer: The content of this article reflect solely the views of the authors. The views presented in this article do not necessarily reflect the current or future opinion or policy of the U.S. Food and Drug Administration. Any mention of commercial products is for clarification and not intended as an endorsement., (©2019 Food Safety Commission, Cabinet Office, Government of Japan.)
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- 2019
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20. Testing the thresholds of toxicological concern values using a new database for food-related substances.
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Reilly L, Serafimova R, Partosch F, Gundert-Remy U, Cortiñas Abrahantes J, Dorne JMC, and Kass GEN
- Subjects
- Consensus, Databases, Factual, Food classification, Hazardous Substances classification, Humans, No-Observed-Adverse-Effect Level, Risk Assessment, Dietary Exposure adverse effects, Food adverse effects, Food Contamination analysis, Hazardous Substances toxicity, Terminology as Topic
- Abstract
The Threshold of Toxicological Concern (TTC) concept integrates data on exposure, chemical structure, toxicity and metabolism to identify a safe exposure threshold value for chemicals with insufficient toxicity data for risk assessment. The TTC values were originally derived from a non-cancer dataset of 613 compounds with a potentially small domain of applicability. There is interest to test whether the TTC values are applicable to a broader range of substances, particularly relevant to food safety using EFSA's new OpenFoodTox database. After exclusion of genotoxic compounds, organophosphates or carbamates or those belonging to the TTC exclusion categories, the remaining 329 substances in the EFSA OpenFoodTox database were categorized under the Cramer decision tree, into low (Class I), moderate (II), or high (III) toxicity profile. For Cramer Classes I and III the threshold values were 1000 μg/person per day (90% confidence interval: 187-2190) and 87 μg/person per day (90% confidence interval: 60-153), respectively, compared to the corresponding original threshold values of 1800 and 90 μg/person per day. This confirms the applicability of the TTC values to substances relevant to food safety. Cramer Class II was excluded from our analysis because of containing too few compounds. Comparison with the Globally Harmonized System of classification confirmed that the Cramer classification scheme in the TTC approach is conservative for substances relevant to food safety., (Copyright © 2019. Published by Elsevier B.V.)
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- 2019
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21. Guidance on the use of the Threshold of Toxicological Concern approach in food safety assessment.
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More SJ, Bampidis V, Benford D, Bragard C, Halldorsson TI, Hernández-Jerez AF, Hougaard Bennekou S, Koutsoumanis KP, Machera K, Naegeli H, Nielsen SS, Schlatter JR, Schrenk D, Silano V, Turck D, Younes M, Gundert-Remy U, Kass GEN, Kleiner J, Rossi AM, Serafimova R, Reilly L, and Wallace HM
- Abstract
The Scientific Committee confirms that the Threshold of Toxicological Concern (TTC) is a pragmatic screening and prioritisation tool for use in food safety assessment. This Guidance provides clear step-by-step instructions for use of the TTC approach. The inclusion and exclusion criteria are defined and the use of the TTC decision tree is explained. The approach can be used when the chemical structure of the substance is known, there are limited chemical-specific toxicity data and the exposure can be estimated. The TTC approach should not be used for substances for which EU food/feed legislation requires the submission of toxicity data or when sufficient data are available for a risk assessment or if the substance under consideration falls into one of the exclusion categories. For substances that have the potential to be DNA-reactive mutagens and/or carcinogens based on the weight of evidence, the relevant TTC value is 0.0025 μg/kg body weight (bw) per day. For organophosphates or carbamates, the relevant TTC value is 0.3 μg/kg bw per day. All other substances are grouped according to the Cramer classification. The TTC values for Cramer Classes I, II and III are 30 μg/kg bw per day, 9 μg/kg bw per day and 1.5 μg/kg bw per day, respectively. For substances with exposures below the TTC values, the probability that they would cause adverse health effects is low. If the estimated exposure to a substance is higher than the relevant TTC value, a non-TTC approach is required to reach a conclusion on potential adverse health effects., (© 2019 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
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- 2019
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22. Naturally occurring bisphenol F in plants used in traditional medicine.
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Huang T, Danaher LA, Brüschweiler BJ, Kass GEN, and Merten C
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- Animals, Humans, Medicine, Chinese Traditional, Plant Extracts, Benzhydryl Compounds analysis, Endocrine Disruptors analysis, Medicine, Traditional, Phenols analysis, Plants, Medicinal chemistry
- Abstract
Bisphenol F (BPF, 4-[(4-hydroxyphenyl)methyl]phenol) is a bisphenol that is structurally similar to bisphenol A (BPA). In response to consumer concern towards BPA, industry has started to substitute BPA for BPF and other bisphenol analogues in the production of epoxy resins and coatings for various applications. In 2016, it was reported that commercially sold mustard contained naturally occurring BPF. Here, the existing literature was reviewed to investigate whether other natural sources of BPF among edible plants exist, including their impact on human exposure to BPF. Coeloglossum viride var. bracteatum (rhizome), Galeola faberi (rhizome), Gastrodia elata (rhizome), Xanthium strumarium (seeds) and Tropidia curculioides (root) were found to contain naturally occurring BPF. Botanical extracts from these plants are used in traditional Chinese medicine. The highest values of BPF were recorded for G. elata and T. curculioides. Information on precise doses of the plant extracts used is scarce; however, for G. elata, also known as Tian Ma and available in powder form, a daily exposure of BPF from this source could theoretically amount up to 4.5 µg/kg body weight per day (based on a 70 kg body weight). Therefore, herbal products used in traditional Chinese medicine should be considered as a potential source contributing to the overall human exposure when assessing endocrine-active bisphenolic compounds.
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- 2019
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23. HNF4alpha expression amplifies the glucocorticoid-induced conversion of a human pancreatic cell line to an hepatocyte-like cell.
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Fairhall EA, Leitch AC, Lakey AF, Abdelghany TM, Ibrahim I, Tosh D, Kass GEN, Wilson C, and Wright MC
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- Gene Expression Profiling, Hepatocyte Nuclear Factor 4 metabolism, Hepatocytes metabolism, Humans, Pancreas metabolism, Tumor Cells, Cultured, Glucocorticoids pharmacology, Hepatocyte Nuclear Factor 4 genetics, Hepatocytes cytology, Hepatocytes drug effects, Pancreas cytology, Pancreas drug effects
- Abstract
The pancreas and liver are closely related developmentally and trans-differentiation of cells from one tissue into the cells of the other has been documented to occur after injury or exposure to selected growth factors or glucocorticoid hormones. To generate a readily-expandable source of human hepatocyte-like (H-13) cells, the human pancreatic adenocarcinoma cell (HPAC) line was stably transfected with a construct encoding the variant 2 hepatocyte nuclear factor 4 α (HNF4α) using a piggyBac vector and transient expression of a transposase. Through induction of transgene HNF4α regulated via an upstream glucocorticoid response element in combination with existing modulating effects of glucocorticoid, H-13 cells were converted into quantitatively similar hepatocyte-like (H-13/H) cells based on expression of a variety of hepatocyte proteins. H-13/H cells also demonstrated the ability to store glycogen and lipids. These data provide proof of concept that regulated expression of genes associated with hepatocyte phenotype could be used to generate quantitatively functional human hepatocyte-like cells using a readily expandable cell source and simple culture protocol. This approach would have utility in Toxicology and Hepatology research., (Copyright © 2018 Elsevier Inc. All rights reserved.)
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- 2018
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24. The ionic liquid 1-octyl-3-methylimidazolium (M8OI) is an activator of the human estrogen receptor alpha.
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Leitch AC, Lakey AF, Hotham WE, Agius L, Kass GEN, Blain PG, and Wright MC
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- Animals, Cells, Cultured, Estrogen Receptor alpha metabolism, HEK293 Cells, Hepatocytes drug effects, Hepatocytes metabolism, Humans, Imidazoles chemistry, Imidazoles metabolism, Ionic Liquids chemistry, Ionic Liquids metabolism, MCF-7 Cells, Mice, Molecular Structure, Estrogen Receptor alpha agonists, Imidazoles pharmacology, Ionic Liquids pharmacology
- Abstract
Recent environmental sampling around a landfill site in the UK demonstrated that unidentified xenoestrogens were present at higher levels than control sites; that these xenoestrogens were capable of super-activating (resisting ligand-dependent antagonism) the murine variant 2 ERβ and that the ionic liquid 1-octyl-3-methylimidazolium chloride (M8OI) was present in some samples. To determine whether M8OI was a contributor to the xenoestrogen pool in the soils, activation of human estrogen receptors by M8OI was examined. M8OI activated the human ERα in MCF7 cells in a dose-response manner. These effects were inhibited by the ER antagonist ICI182780; occurred in the absence of any metabolism of M8OI and were confirmed on examination of ER-dependent induction of trefoil factor 1 mRNA in MCF7 cells. M8OI also super-activated the murine variant 2 ERβ in a murine hepatopancreatobiliary cell line. The human ERβ was not activated by M8OI when expressed in HEK293 cells. These data demonstrate that M8OI is a xenoestrogen capable of activating the human ERα and super-activating the murine variant 2 ERβ., (Copyright © 2018 Elsevier Inc. All rights reserved.)
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- 2018
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25. Scientific opinion on pesticides in foods for infants and young children.
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Ockleford C, Adriaanse P, Hougaard Bennekou S, Berny P, Brock T, Duquesne S, Grilli S, Hernandez-Jerez AF, Klein M, Kuhl T, Laskowski R, Machera K, Pelkonen O, Pieper S, Smith R, Stemmer M, Sundh I, Teodorovic I, Tiktak A, Topping CJ, Gundert-Remy U, Kersting M, Waalkens-Berendsen I, Chiusolo A, Court Marques D, Dujardin B, Kass GEN, Mohimont L, Nougadère A, Reich H, and Wolterink G
- Abstract
Following a request from the European Commission, the EFSA Panel on Plant Protection Products and their Residues (PPR Panel) prepared a scientific opinion to provide a comprehensive evaluation of pesticide residues in foods for infants and young children. In its approach to develop this scientific opinion, the EFSA PPR Panel took into account, among the others, (i) the relevant opinions of the Scientific Committee for Food setting a default maximum residue level (MRL) of 0.01 mg/kg for pesticide residues in foods for infants and young children; (ii) the recommendations provided by EFSA Scientific Committee in a guidance on risk assessment of substances present in food intended for infants below 16 weeks of age; (iii) the knowledge on organ/system development in infants and young children. For infants below 16 weeks of age, the EFSA PPR Panel concluded that pesticide residues at the default MRL of 0.01 mg/kg for food for infants and young children are not likely to result in an unacceptable exposure for active substances for which a health-based guidance value (HBGV) of 0.0026 mg/kg body weight (bw) per day or higher applies. Lower MRLs are recommended for active substances with HBGVs below this value. For infants above 16 weeks of age and young children, the established approach for setting HBGVs is considered appropriate. For infants below 16 weeks of age the approach may not be appropriate and the application of the EFSA guidance on risk assessment of substances present in food intended for infants below 16 weeks of age is recommended. The contribution of conventional food to the total exposure to pesticide residues is much higher than that from foods intended for infants and young children. Because of the increased intake of conventional food by young children, these have the highest exposure to pesticide residues, whereas infants 3-6 months of age generally have lower exposure. The impact of cumulative exposure to pesticide residues on infants and young children is not different from the general population and the EFSA cumulative risk assessment methodology is also applicable to these age groups. Residue definitions established under Regulation (EC) No 396/2005 are in general considered appropriate also for foods for infants and young children. However, based on a tier 1 analysis of the hydrolysis potential of pesticides simulating processing, the particular appropriateness of existing residue definitions for monitoring to cover processed food, both intended for infants and young children as well as conventional food, is questionable., (© 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
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- 2018
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26. Development of a novel scoring system for identifying emerging chemical risks in the food chain.
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Oltmanns J, Licht O, Bitsch A, Bohlen ML, Escher SE, Silano V, MacLeod M, Serafimova R, Kass GEN, and Merten C
- Subjects
- Humans, Pilot Projects, Risk Assessment methods, Food Chain, Food Safety methods, Hazardous Substances chemistry, Hazardous Substances classification, Hazardous Substances toxicity
- Abstract
The European Food Safety Authority (EFSA) is responsible for risk assessment of all aspects of food safety, including the establishment of procedures aimed at the identification of emerging risks to food safety. Here, a scoring system was developed for identifying chemicals registered under the European REACH Regulation that could be of potential concern in the food chain using the following parameters: (i) environmental release based on maximum aggregated tonnages and environmental release categories; (ii) biodegradation in the environment; (iii) bioaccumulation and in vivo and in vitro toxicity. The screening approach was tested on 100 data-rich chemicals registered under the REACH Regulation at aggregated volumes of at least 1000 tonnes per annum. The results show that substance-specific data generated under the REACH Regulation can be used to identify potential emerging risks in the food chain. After application of the screening procedure, priority chemicals can be identified as potentially emerging risk chemicals through the integration of exposure, environmental fate and toxicity. The default approach is to generate a single total score for each substance using a predefined weighting scenario. However, it is also possible to use a pivot table approach to combine the individual scores in different ways that reflect user-defined priorities, which enables a very flexible, iterative definition of screening criteria. Possible applications of the approaches are discussed using illustrative examples. Either approach can then be followed by in-depth evaluation of priority substances to ensure the identification of substances that present a real emerging chemical risk in the food chain.
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- 2018
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27. B-13 progenitor-derived hepatocytes (B-13/H cells) model lipid dysregulation in response to drugs and chemicals.
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Leitch AC, Probert PME, Shayman JA, Meyer SK, Kass GEN, and Wright MC
- Subjects
- Animals, Benzoates administration & dosage, Benzoates toxicity, Benzylamines administration & dosage, Benzylamines toxicity, Cell Line, Chemical and Drug Induced Liver Injury etiology, Dose-Response Relationship, Drug, Fatty Liver metabolism, Hepatocytes metabolism, Hydrocarbons, Fluorinated administration & dosage, Hydrocarbons, Fluorinated toxicity, Liver X Receptors metabolism, Methapyrilene administration & dosage, Methapyrilene toxicity, Phospholipids metabolism, Rats, Sulfonamides administration & dosage, Sulfonamides toxicity, Time Factors, Chemical and Drug Induced Liver Injury physiopathology, Fatty Acids metabolism, Hepatocytes drug effects, Lipid Metabolism drug effects, Triglycerides metabolism
- Abstract
Lipid dysregulation is a common hepatic adverse outcome after exposure to toxic drugs and chemicals. A donor-free rat hepatocyte-like (B-13/H) cell was therefore examined as an in vitro model for investigating mechanisms. The B-13/H cell irreversibly accumulated triglycerides (steatosis) in a time- and dose-dependent manner when exposed to fatty acids, an effect that was potentiated by the combined addition of hyperglycaemic levels of glucose and insulin. B-13/H cells also expressed the LXR nuclear receptors and exposure to their activators - T0901317 or GW3965 - induced luciferase expression from a transfected LXR-regulated reporter gene construct and steatosis in a dose-dependent manner with T0901317. Exposing B-13/H cells to a variety of cationic amphiphilic drugs - but not other hepatotoxins - also resulted in a time- and dose-dependent accumulation of phospholipids (phospholipidosis), an effect that was reduced by over-expression of lysosomal phospholipase A2. Through application of this model, hepatotoxin methapyrilene exposure was shown to induce phospholipidosis in both B-13 and B-13/H cells in a time- and dose-dependent manner. However, methapyrilene was only toxic to B-13/H cells and inhibitors of hepatotoxicity enhanced phospholipidosis, suggesting phospholipidosis is not a pathway in toxicity for this withdrawn drug. In contrast, pre-existing steatosis had minimal effect on methapyrilene hepatotoxicity in B-13/H cells. These data demonstrate that the donor free B-13 cell system for generating hepatocyte-like cells may be employed in studies of fatty acid- and LXR activator-induced steatosis and phospholipidosis and in the dissection of pathways leading to adverse outcomes such as hepatotoxicity., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
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28. Hepatic effects of tartrazine (E 102) after systemic exposure are independent of oestrogen receptor interactions in the mouse.
- Author
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Meyer SK, Probert PME, Lakey AF, Axon AR, Leitch AC, Williams FM, Jowsey PA, Blain PG, Kass GEN, and Wright MC
- Subjects
- Administration, Oral, Animals, Cell Line, Estradiol pharmacology, Estrogen Receptor alpha genetics, Estrogen Receptor beta genetics, Ethanol toxicity, Female, Injections, Intraperitoneal, Liver metabolism, Liver Function Tests, Luciferases, Firefly genetics, Male, Mice, Inbred C57BL, Mice, Transgenic, NF-kappa B genetics, Estrogen Receptor alpha metabolism, Estrogen Receptor beta metabolism, Food Coloring Agents toxicity, Liver drug effects, Tartrazine toxicity
- Abstract
Tartrazine is a food colour that activates the transcriptional function of the human oestrogen receptor alpha in an in vitro cell model. Since oestrogens are cholestatic, we hypothesised tartrazine will cause periportal injury to the liver in vivo. To test this hypothesis, tartrazine was initially administered systemically to mice resulting in a periportal recruitment of inflammatory cells, increased serum alkaline phosphatase activity and mild periportal fibrosis. To determine whether an oestrogenic effect may be a key event in this response, tartrazine, sulphonated metabolites and a food additive contaminant were screened for their ability to interact with murine oestrogen receptors. In all cases, there were no interactions as agonists or antagonists and further, no oestrogenicity was observed with tartrazine in an in vivo uterine growth assay. To examine the relevance of the hepatic effects of tartrazine to its use as a food additive, tartrazine was orally administered to transgenic NF-κB-Luc mice. Pre- and concurrent oral treatment with alcohol was incorporated given its potential to promote gut permeability and hepatic inflammation. Tartrazine alone induced NF- κB activities in the colon and liver but there was no periportal recruitment of inflammatory cells or fibrosis. Tartrazine, its sulphonated metabolites and the contaminant inhibited sulphotransferase activities in murine hepatic S9 extracts. Given the role of sulfotransferases in bile acid excretion, the initiating event giving rise to periportal inflammation and subsequent hepatic pathology through systemic tartrazine exposure is therefore potentially associated an inhibition of bile acid sulphation and excretion and not on oestrogen receptor-mediated transcriptional function. However, these effects were restricted to systemic exposures to tartrazine and did not occur to any significant effect after oral exposure., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
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29. Human herpesvirus 1 protein US3 induces an inhibition of mitochondrial electron transport.
- Author
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Derakhshan M, Willcocks MM, Salako MA, Kass GEN, and Carter MJ
- Subjects
- Animals, Calicivirus, Feline pathogenicity, Cats, Cell Line, Cytomegalovirus pathogenicity, Dogs, Enterovirus pathogenicity, Humans, Influenza A virus pathogenicity, Measles virus pathogenicity, Oxygen Consumption, Cell Respiration, Electron Transport, Herpesvirus 1, Human pathogenicity, Mitochondria metabolism, Protein Serine-Threonine Kinases physiology, Succinate Cytochrome c Oxidoreductase antagonists & inhibitors, Viral Proteins physiology
- Abstract
Previous studies have identified virus proteins that traffic to mitochondria and may affect mitochondrial function. Here, it is reported that Human herpesvirus 1 (HHV-1, herpes simplex virus 1) and influenza virus reduced mitochondrial respiration, whilst Measles virus, cytomegalovirus, coxsackievirus B4 and Feline calicivirus did not. The inhibition of total cellular respiration was caused by a block in the mitochondrial electron-transport chain. This effect occurred during beta-phase protein synthesis and the inhibition of mitochondrial respiration could be reproduced by ectopic expression of the beta-phase protein US3. An HHV-1 mutant lacking this protein failed to inhibit oxygen consumption in infected cells relative to controls. It was concluded that US3 was mediating the suppression of mitochondrial respiration following HHV-1 infection. The integrity of the electron-transport chain in HHV-1-infected cells was analysed further and the site of the block in electron transport was located between complexes II and III, a site previously shown to be affected by Poliovirus.
- Published
- 2006
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30. The mitochondrial pathway of apoptosis is triggered during feline calicivirus infection.
- Author
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Natoni A, Kass GEN, Carter MJ, and Roberts LO
- Subjects
- Animals, Caspase Inhibitors, Caspases genetics, Cats, Cell Line, Cells, Cultured, Cytochrome c Group metabolism, Enzyme Activation, Kidney, Apoptosis physiology, Calicivirus, Feline pathogenicity, Caspases metabolism, Mitochondria metabolism
- Abstract
Feline calicivirus (FCV) belongs to the family Caliciviridae and is an important pathogen of the upper respiratory tract of cats. Recent studies have shown that cells infected with FCV undergo apoptosis, as evidenced by caspase activation, chromatin condensation and cleavage of poly(ADP-ribose) polymerase. Here, the upstream events were investigated in order to define the molecular mechanism of apoptosis in FCV-infected cells. It was shown that FCV induced translocation of phosphatidylserine to the cell outer membrane and release of cytochrome c from mitochondria at about 6-8 h post-infection. These events were preceded by the loss of mitochondrial membrane potential and Bax translocation from the cytosol to mitochondria between 4 and 6 h after infection. Release of cytochrome c from mitochondria triggered the activation of caspase-9 and the subsequent activation of the executioner caspase, caspase-3. These results suggest that the mitochondrial pathway of apoptosis is triggered during FCV infection.
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- 2006
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31. Caspase-mediated cleavage of the feline calicivirus capsid protein.
- Author
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Al-Molawi N, Beardmore VA, Carter MJ, Kass GEN, and Roberts LO
- Subjects
- Animals, Apoptosis, Caspase Inhibitors, Caspases genetics, Cats, Cell Line, Enzyme Activation, Humans, Recombinant Proteins genetics, Recombinant Proteins metabolism, Calicivirus, Feline pathogenicity, Capsid Proteins metabolism, Caspases metabolism
- Abstract
Feline calicivirus (FCV) is responsible for an acute upper respiratory tract disease in cats. The FCV capsid protein is synthesized as a precursor (76 kDa) that is post-translationally processed into the mature 62 kDa capsid protein by removal of the N-terminal 124 amino acids. Our previous studies have also detected a 40 kDa protein, related to the FCV capsid protein, produced during infection. Here we demonstrate that cleavage of the FCV capsid protein, during infection of cells in culture, was prevented by caspase inhibitors. In addition, caspase-2, -3 and -7 were activated during FCV infection, as shown by pro-form processing, an increase in N-acetyl-Asp-Glu-Val-Asp-7-amido-4-trifluoromethylcoumarin cleavage activity and in situ poly(ADP-ribose) polymerase cleavage. Caspase activation coincided with the induction of apoptosis and capsid cleavage to the 40 kDa fragment. An in vitro cleavage assay, using recombinant human caspases and in vitro-derived FCV capsid protein, revealed that caspase-2, and to a lesser extent caspase-6, cleaved the capsid protein to generate a 40 kDa fragment. Taken together, these results suggest that FCV triggers apoptosis within infected cells and that caspase-induced capsid cleavage occurs concomitantly with apoptosis. The possible role of capsid cleavage in the pathogenesis of FCV infection is discussed.
- Published
- 2003
- Full Text
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