The initial compositional analysis of plants plays an important role within the internationally h... more The initial compositional analysis of plants plays an important role within the internationally harmonized comparative safety assessment approach for genetically modified plants. Current EFSA guidance prescribes two types of comparison, namely difference tests with regard to a conventional comparator or control, and equivalence tests with regard to a collection of commercial reference varieties. The experience gained so far shows that most of the statistically significant differences between the test and control can be discounted based on the fact that they are still within equivalence limits of reference varieties with a presumed history of safe use. Inclusion of a test variety and reference varieties into field trial design, and of the statistical equivalence test would already suffice for the purpose of finding relevant parameters that warrant further assessment, hence both the inclusion of a conventional counterpart and the performance of difference testing can be omitted. This ...
An extensive literature relating to public perceptions of genetically modified foods applied to a... more An extensive literature relating to public perceptions of genetically modified foods applied to agri-food production has been identified through the process of systematic review. Application of systematic review criteria indicated that 335 papers were of appropriate quality or relevance to be considered in the systematic review. Of these, 70 contained data (or data which could be accessed by contacting the authors) which were amenable to formal meant-analysis. The analysis excluded research which utilised willingness-to-pay as the dependent variable as these had been the subject of a relatively recent meta-analysis. Insufficient qualitative research was identified to include these papers in an additional the formal systematic analysis. The results indicate that most data had been collected in Europe, North America, and, to a lesser extent, Australia and new Zealand, and Asia. It is therefore not possible to make conclusions about some major EU trading partners (in particular the BRI...
Novel proteins entering the food chain, for example by genetic modification of plants, have to be... more Novel proteins entering the food chain, for example by genetic modification of plants, have to be tested for allergenicity. Allermatch http://allermatch.org is a webtool for the efficient and standardized prediction of potential allergenicity of proteins and peptides according to the current recommendations of the FAO/WHO Expert Consultation, as outlined in the Codex alimentarius. A query amino acid sequence is compared with all known allergenic proteins retrieved from the protein databases using a sliding window approach. This identifies stretches of 80 amino acids with more than 35% similarity or small identical stretches of at least six amino acids. The outcome of the analysis is presented in a concise format. The predictive performance of the FAO/WHO criteria is evaluated by screening sets of allergens and non-allergens against the Allermatch databases. Besides correct predictions, both methods are shown to generate false positive and false negative hits and the outcomes should ...
The Maillard reaction between sugar and protein has been postulated as the cause for the browning... more The Maillard reaction between sugar and protein has been postulated as the cause for the browning and arrestment of caries lesions. This reaction has been implicated as the cause for decreased degradability of collagen in vivo. The aim of the present study was to verify the occurrence of the reaction in vivo. Carious and sound dentin samples were taken from extracted human teeth and analyzed for the fluorescence characteristic of the Maillard reaction and oxidation and, by HPLC, for Maillard products. In addition, physiological cross-links were analyzed by HPLC. Oxidation- and Maillard reaction-related fluore-scence increased in collagenase digests from carious dentin. Advanced Maillard products (carboxymethyllysine and pentosidine) increased, whereas furosine, a marker for the initial reaction, was not observed consistently. This implies no direct addition of sugars to protein, but rather the addi-tion of smaller metabolites and glycoxidation products. In addition, the physiologica...
Background Since more than one hundred events of genetically modified organisms (GMOs) have been ... more Background Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. Results GMO Detection method Database (GMDD) has collected almost all the previous developed and reported GMOs detection methods, which have been grouped by different strategies (screen-, gene-, construct-, and event-specific), and also provide a user-friendly search service of the detection methods by GMO event name, exogenous gene, or protein information, etc. In this database, users can obtain the sequences of exogenous integration, which will facilitate PCR primers and probes design. Also the infor...
Background: Rodent feeding trials are frequently applied to assess the safety of genetically modi... more Background: Rodent feeding trials are frequently applied to assess the safety of genetically modified plants. Even though their added value is controversially discussed within the scientific community, the Implementing Regulation (EU) No 503/2013 requests their mandatory conduct during the approval process of genetically modified plants for being placed on the European market. This systematic review aims at providing a comprehensive synthesis and critical appraisal of results from rodent feeding trials with whole genetically modified food/feed being performed to determine their potential to cause general signs of toxicity and/or carcinogenicity in the test animals. Methods: This study follows the systematic review approach to identify, select, appraise and synthesis data from included studies. The selection and critical appraisal process will be done by two reviewers independently from each other, whereas data will be extracted by one reviewer and rechecked by a second one. This rev...
SCIENTIFIC OPINION Application (Reference EFSA-GMO-CZ-2006-33) for the placing on the market of t... more SCIENTIFIC OPINION Application (Reference EFSA-GMO-CZ-2006-33) for the placing on the market of the insect-resistant and glyphosate-tolerant genetically modified maize MON 88017 x MON 810, for food and feed uses, import and processing under Regulation (EC) No 1829/2003 from Monsanto1
Journal of agricultural and food chemistry, Jan 9, 2015
In order to provide sufficient food and fibre to the increasing global population the technologie... more In order to provide sufficient food and fibre to the increasing global population the technologies associated with crop protection are growing ever more sophisticated but, at the same time, societal expectations for the safe use of crop protection chemistry tools, are also increasing. The goal of this perspective is to highlight the key issues that face future leaders in crop protection, based on presentations made during a symposium, entitled "Developing Global Leaders for Research, Regulation and Stewardship of Crop Protection Chemistry in the 21st Century", held in conjunction with the IUPAC 13th International Congress of Pesticide Chemistry in San Francisco, CA during August 2014. The presentations highlighted the fact that leaders in crop protection must have a good basic scientific training, understand new and evolving technologies, are aware of the needs of both developed and developing countries and have good communication skills. Concern is expressed over the appa...
The potential effects of horizontal gene transfer on human health are an important item in the sa... more The potential effects of horizontal gene transfer on human health are an important item in the safety assessment of genetically modified organisms. Horizontal gene transfer from genetically modified crops to gut microflora most likely occurs with transgenes of microbial origin. The characteristics of microbial transgenes other than antibiotic-resistance genes in market-approved genetically modified crops are reviewed. These characteristics include the microbial source, natural function, function in genetically modified crops, natural prevalence, geographical distribution, similarity to other microbial genes, known horizontal transfer activity, selective conditions and environments for horizontally transferred genes, and potential contribution to pathogenicity and virulence in humans and animals. The assessment of this set of data for each of the microbial genes reviewed does not give rise to health concerns. We recommend including the above-mentioned items into the premarket safety ...
The initial compositional analysis of plants plays an important role within the internationally h... more The initial compositional analysis of plants plays an important role within the internationally harmonized comparative safety assessment approach for genetically modified plants. Current EFSA guidance prescribes two types of comparison, namely difference tests with regard to a conventional comparator or control, and equivalence tests with regard to a collection of commercial reference varieties. The experience gained so far shows that most of the statistically significant differences between the test and control can be discounted based on the fact that they are still within equivalence limits of reference varieties with a presumed history of safe use. Inclusion of a test variety and reference varieties into field trial design, and of the statistical equivalence test would already suffice for the purpose of finding relevant parameters that warrant further assessment, hence both the inclusion of a conventional counterpart and the performance of difference testing can be omitted. This ...
An extensive literature relating to public perceptions of genetically modified foods applied to a... more An extensive literature relating to public perceptions of genetically modified foods applied to agri-food production has been identified through the process of systematic review. Application of systematic review criteria indicated that 335 papers were of appropriate quality or relevance to be considered in the systematic review. Of these, 70 contained data (or data which could be accessed by contacting the authors) which were amenable to formal meant-analysis. The analysis excluded research which utilised willingness-to-pay as the dependent variable as these had been the subject of a relatively recent meta-analysis. Insufficient qualitative research was identified to include these papers in an additional the formal systematic analysis. The results indicate that most data had been collected in Europe, North America, and, to a lesser extent, Australia and new Zealand, and Asia. It is therefore not possible to make conclusions about some major EU trading partners (in particular the BRI...
Novel proteins entering the food chain, for example by genetic modification of plants, have to be... more Novel proteins entering the food chain, for example by genetic modification of plants, have to be tested for allergenicity. Allermatch http://allermatch.org is a webtool for the efficient and standardized prediction of potential allergenicity of proteins and peptides according to the current recommendations of the FAO/WHO Expert Consultation, as outlined in the Codex alimentarius. A query amino acid sequence is compared with all known allergenic proteins retrieved from the protein databases using a sliding window approach. This identifies stretches of 80 amino acids with more than 35% similarity or small identical stretches of at least six amino acids. The outcome of the analysis is presented in a concise format. The predictive performance of the FAO/WHO criteria is evaluated by screening sets of allergens and non-allergens against the Allermatch databases. Besides correct predictions, both methods are shown to generate false positive and false negative hits and the outcomes should ...
The Maillard reaction between sugar and protein has been postulated as the cause for the browning... more The Maillard reaction between sugar and protein has been postulated as the cause for the browning and arrestment of caries lesions. This reaction has been implicated as the cause for decreased degradability of collagen in vivo. The aim of the present study was to verify the occurrence of the reaction in vivo. Carious and sound dentin samples were taken from extracted human teeth and analyzed for the fluorescence characteristic of the Maillard reaction and oxidation and, by HPLC, for Maillard products. In addition, physiological cross-links were analyzed by HPLC. Oxidation- and Maillard reaction-related fluore-scence increased in collagenase digests from carious dentin. Advanced Maillard products (carboxymethyllysine and pentosidine) increased, whereas furosine, a marker for the initial reaction, was not observed consistently. This implies no direct addition of sugars to protein, but rather the addi-tion of smaller metabolites and glycoxidation products. In addition, the physiologica...
Background Since more than one hundred events of genetically modified organisms (GMOs) have been ... more Background Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. Results GMO Detection method Database (GMDD) has collected almost all the previous developed and reported GMOs detection methods, which have been grouped by different strategies (screen-, gene-, construct-, and event-specific), and also provide a user-friendly search service of the detection methods by GMO event name, exogenous gene, or protein information, etc. In this database, users can obtain the sequences of exogenous integration, which will facilitate PCR primers and probes design. Also the infor...
Background: Rodent feeding trials are frequently applied to assess the safety of genetically modi... more Background: Rodent feeding trials are frequently applied to assess the safety of genetically modified plants. Even though their added value is controversially discussed within the scientific community, the Implementing Regulation (EU) No 503/2013 requests their mandatory conduct during the approval process of genetically modified plants for being placed on the European market. This systematic review aims at providing a comprehensive synthesis and critical appraisal of results from rodent feeding trials with whole genetically modified food/feed being performed to determine their potential to cause general signs of toxicity and/or carcinogenicity in the test animals. Methods: This study follows the systematic review approach to identify, select, appraise and synthesis data from included studies. The selection and critical appraisal process will be done by two reviewers independently from each other, whereas data will be extracted by one reviewer and rechecked by a second one. This rev...
SCIENTIFIC OPINION Application (Reference EFSA-GMO-CZ-2006-33) for the placing on the market of t... more SCIENTIFIC OPINION Application (Reference EFSA-GMO-CZ-2006-33) for the placing on the market of the insect-resistant and glyphosate-tolerant genetically modified maize MON 88017 x MON 810, for food and feed uses, import and processing under Regulation (EC) No 1829/2003 from Monsanto1
Journal of agricultural and food chemistry, Jan 9, 2015
In order to provide sufficient food and fibre to the increasing global population the technologie... more In order to provide sufficient food and fibre to the increasing global population the technologies associated with crop protection are growing ever more sophisticated but, at the same time, societal expectations for the safe use of crop protection chemistry tools, are also increasing. The goal of this perspective is to highlight the key issues that face future leaders in crop protection, based on presentations made during a symposium, entitled "Developing Global Leaders for Research, Regulation and Stewardship of Crop Protection Chemistry in the 21st Century", held in conjunction with the IUPAC 13th International Congress of Pesticide Chemistry in San Francisco, CA during August 2014. The presentations highlighted the fact that leaders in crop protection must have a good basic scientific training, understand new and evolving technologies, are aware of the needs of both developed and developing countries and have good communication skills. Concern is expressed over the appa...
The potential effects of horizontal gene transfer on human health are an important item in the sa... more The potential effects of horizontal gene transfer on human health are an important item in the safety assessment of genetically modified organisms. Horizontal gene transfer from genetically modified crops to gut microflora most likely occurs with transgenes of microbial origin. The characteristics of microbial transgenes other than antibiotic-resistance genes in market-approved genetically modified crops are reviewed. These characteristics include the microbial source, natural function, function in genetically modified crops, natural prevalence, geographical distribution, similarity to other microbial genes, known horizontal transfer activity, selective conditions and environments for horizontally transferred genes, and potential contribution to pathogenicity and virulence in humans and animals. The assessment of this set of data for each of the microbial genes reviewed does not give rise to health concerns. We recommend including the above-mentioned items into the premarket safety ...
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