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1.
J Clin Virol ; 152: 105191, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35640400

RESUMO

OBJECTIVES: The aim of this study was to develop a RT-PCR assay for the specific detection of the SARS-CoV-2 Omicron Variant of Concern (VOC) as a rapid alternative to sequencing. METHODS: A RT-PCR was designed in silico and then validated using characterised clinical samples containing Omicron (both BA.1 and BA.2 lineages) and the Omicron synthetic RNA genome. As negative controls, SARS-CoV-2 positive clinical samples collected in May 2020, and synthetic RNA genomes of the isolate Wuhan Hu-1 and of the Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Kappa (B.1.617.1), Iota (B.1.526), Epsilon (B.1.429) and Delta (B.1.617.2) SARS-CoV-2 VOC were used. RESULTS: Experiments performed using as templates the synthetic RNA genomes demonstrate the high specificity of the PCR-method for the SARS-CoV-2 Omicron. Despite the synthetic RNAs were used at high copy numbers, specific signal was mainly detected with the Omicron synthetic genome. Only a non-specific late signal was detected using the Alpha variant genome, but these results were considered negligible as Alpha VOC has been replaced by the Delta and it is not circulating anymore in the world. Using our method, we confirmed the presence of Omicron on clinical samples containing this variant but not of other SARS-CoV-2 lineages. The method is highly sensitive and can detect up to 1 cp of the Omicron virus per µl. CONCLUSIONS: The method presented here, in combination with other methods in use for detection of SARS-CoV-2, can be used for an early identification of Omicron.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Humanos , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética , Sensibilidade e Especificidade
2.
Mol Oncol ; 15(10): 2507-2543, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34515408

RESUMO

Key stakeholders from the cancer research continuum met in May 2021 at the European Cancer Research Summit in Porto to discuss priorities and specific action points required for the successful implementation of the European Cancer Mission and Europe's Beating Cancer Plan (EBCP). Speakers presented a unified view about the need to establish high-quality, networked infrastructures to decrease cancer incidence, increase the cure rate, improve patient's survival and quality of life, and deal with research and care inequalities across the European Union (EU). These infrastructures, featuring Comprehensive Cancer Centres (CCCs) as key components, will integrate care, prevention and research across the entire cancer continuum to support the development of personalized/precision cancer medicine in Europe. The three pillars of the recommended European infrastructures - namely translational research, clinical/prevention trials and outcomes research - were pondered at length. Speakers addressing the future needs of translational research focused on the prospects of multiomics assisted preclinical research, progress in Molecular and Digital Pathology, immunotherapy, liquid biopsy and science data. The clinical/prevention trial session presented the requirements for next-generation, multicentric trials entailing unified strategies for patient stratification, imaging, and biospecimen acquisition and storage. The third session highlighted the need for establishing outcomes research infrastructures to cover primary prevention, early detection, clinical effectiveness of innovations, health-related quality-of-life assessment, survivorship research and health economics. An important outcome of the Summit was the presentation of the Porto Declaration, which called for a collective and committed action throughout Europe to develop the cancer research infrastructures indispensable for fostering innovation and decreasing inequalities within and between member states. Moreover, the Summit guidelines will assist decision making in the context of a unique EU-wide cancer initiative that, if expertly implemented, will decrease the cancer death toll and improve the quality of life of those confronted with cancer, and this is carried out at an affordable cost.


Assuntos
Neoplasias , Qualidade de Vida , Europa (Continente)/epidemiologia , Humanos , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Medicina de Precisão , Pesquisa Translacional Biomédica
3.
Viruses ; 13(7)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34372565

RESUMO

More than a year after the first identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as the causative agent of the 2019 coronavirus disease (COVID-19) in China, the emergence and spread of genomic variants of this virus through travel raise concerns regarding the introduction of lineages in previously unaffected regions, requiring adequate containment strategies. Concomitantly, such introductions fuel worries about a possible increase in transmissibility and disease severity, as well as a possible decrease in vaccine efficacy. Military personnel are frequently deployed on missions around the world. As part of a COVID-19 risk mitigation strategy, Belgian Armed Forces that engaged in missions and operations abroad were screened (7683 RT-qPCR tests), pre- and post-mission, for the presence of SARS-CoV-2, including the identification of viral lineages. Nine distinct viral genotypes were identified in soldiers returning from operations in Niger, the Democratic Republic of the Congo, Afghanistan, and Mali. The SARS-CoV-2 variants belonged to major clades 19B, 20A, and 20B (Nextstrain nomenclature), and included "variant of interest" B.1.525, "variant under monitoring" A.27, as well as lineages B.1.214, B.1, B.1.1.254, and A (pangolin nomenclature), some of which are internationally monitored due to the specific mutations they harbor. Through contact tracing and phylogenetic analysis, we show that isolation and testing policies implemented by the Belgian military command appear to have been successful in containing the influx and transmission of these distinct SARS-CoV-2 variants into military and civilian populations.


Assuntos
COVID-19/virologia , Militares , SARS-CoV-2/classificação , SARS-CoV-2/genética , Afeganistão/epidemiologia , Bélgica , COVID-19/epidemiologia , China/epidemiologia , República Democrática do Congo/epidemiologia , Genoma Viral , Genômica , Humanos , Mali/epidemiologia , Epidemiologia Molecular , Mutação , Níger/epidemiologia , Filogenia , Viagem , Sequenciamento Completo do Genoma
4.
F1000Res ; 10: 370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336189

RESUMO

Background Scientific evidence for the involvement of human microbiota in the development of COVID-19 disease has been reported recently. SARS-CoV-2 RNA presence in human faecal samples and SARS-CoV-2 activity in faeces from COVID-19 patients have been observed. Methods Starting from these observations, an experimental design was developed to cultivate in vitro faecal microbiota from infected individuals, to monitor the presence of SARS-CoV-2, and to collect data on the relationship between faecal bacteria and the virus. Results Our results indicate that SARS-CoV-2 replicates in vitro in bacterial growth medium, that the viral replication follows bacterial growth and it is influenced by the administration of specific antibiotics. SARS-CoV-2-related peptides have been detected in 30-day bacterial cultures and characterised. Discussion Our observations are compatible with a 'bacteriophage-like' behaviour of SARS-CoV-2, which, to our knowledge has not been observed or described before. These results are unexpected and hint towards a novel hypothesis on the biology of SARS-CoV-2 and on the COVID-19 epidemiology. The discovery of possible new modes of action of SARS-CoV-2 has far-reaching implications for the prevention and the treatment of the disease.


Assuntos
COVID-19 , SARS-CoV-2 , Biologia , Fezes , Humanos , RNA Viral
5.
F1000Res ; 10: 550, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35106136

RESUMO

Background: SARS-CoV-2 that causes COVID-19 disease and led to the pandemic currently affecting the world has been broadly investigated. Different studies have been performed to understand the infection mechanism, and the involved human genes, transcripts and proteins. In parallel, numerous clinical extra-pulmonary manifestations co-occurring with COVID-19 disease have been reported and evidence of their severity and persistence is increasing. Whether these manifestations are linked to other disorders co-occurring with SARS-CoV-2 infection, is under discussion. In this work, we report the identification of toxin-like peptides in COVID-19 patients by application of the Liquid Chromatography Surface-Activated Chemical Ionization - Cloud Ion Mobility Mass Spectrometry.   Methods: Plasma, urine and faecal samples from COVID-19 patients and control individuals were analysed to study peptidomic toxins' profiles. Protein precipitation preparation procedure was used for plasma, to remove high molecular weight proteins and efficiently solubilize the peptide fraction; in the case of faeces and urine, direct peptide solubilization was employed.   Results: Toxin-like peptides, almost identical to toxic components of venoms from animals, like conotoxins, phospholipases, phosphodiesterases, zinc metal proteinases, and bradykinins, were identified in samples from COVID-19 patients, but not in control samples.  Conclusions: The presence of toxin-like peptides could potentially be connected to SARS-CoV-2 infection. Their presence suggests a possible association between COVID-19 disease and the release in the body of (oligo-)peptides almost identical to toxic components of venoms from animals. Their involvement in a large set of heterogeneous extra-pulmonary COVID-19 clinical manifestations, like neurological ones, cannot be excluded. Although the presence of each individual symptom is not selective of the disease, their combination might be related to COVID-19 by the coexistence of the panel of the here detected toxin-like peptides. The presence of these peptides opens new scenarios on the aetiology of the COVID-19 clinical symptoms observed up to now, including neurological manifestations.


Assuntos
COVID-19 , Fezes , Humanos , Pandemias , Peptídeos , SARS-CoV-2
6.
F1000Res ; 10: 80, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35847383

RESUMO

Next Generation Sequencing technologies significantly impact the field of Antimicrobial Resistance (AMR) detection and monitoring, with immediate uses in diagnosis and risk assessment. For this application and in general, considerable challenges remain in demonstrating sufficient trust to act upon the meaningful information produced from raw data, partly because of the reliance on bioinformatics pipelines, which can produce different results and therefore lead to different interpretations. With the constant evolution of the field, it is difficult to identify, harmonise and recommend specific methods for large-scale implementations over time. In this article, we propose to address this challenge through establishing a transparent, performance-based, evaluation approach to provide flexibility in the bioinformatics tools of choice, while demonstrating proficiency in meeting common performance standards. The approach is two-fold: first, a community-driven effort to establish and maintain "live" (dynamic) benchmarking platforms to provide relevant performance metrics, based on different use-cases, that would evolve together with the AMR field; second, agreed and defined datasets to allow the pipelines' implementation, validation, and quality-control over time. Following previous discussions on the main challenges linked to this approach, we provide concrete recommendations and future steps, related to different aspects of the design of benchmarks, such as the selection and the characteristics of the datasets (quality, choice of pathogens and resistances, etc.), the evaluation criteria of the pipelines, and the way these resources should be deployed in the community.


Assuntos
Benchmarking , Sequenciamento de Nucleotídeos em Larga Escala , Antibacterianos/farmacologia , Biologia Computacional/métodos , Farmacorresistência Bacteriana/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos
7.
Viruses ; 12(9)2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867108

RESUMO

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compromises the ability of military forces to fulfill missions. At the beginning of May 2020, 22 out of 70 Belgian soldiers deployed to a military education and training center in Maradi, Niger, developed mild COVID-19 compatible symptoms. Immediately upon their return to Belgium, and two weeks later, all seventy soldiers were tested for SARS-CoV-2 RNA (RT-qPCR) and antibodies (two immunoassays). Nine soldiers had at least one positive COVID-19 diagnostic test result. Five of them exhibited COVID-19 symptoms (mainly anosmia, ageusia, and fever), while four were asymptomatic. In four soldiers, SARS-CoV-2 viral load was detected and the genomes were sequenced. Conventional and genomic epidemiological data suggest that these genomes have an African most recent common ancestor and that the Belgian military service men were infected through contact with locals. The medical military command implemented testing of all Belgian soldiers for SARS-CoV-2 viral load and antibodies, two to three days before their departure on a mission abroad or on the high seas, and for specific missions immediately upon their return in Belgium. Some military operational settings (e.g., training camps in austere environments and ships) were also equipped with mobile infectious disease (COVID-19) testing capacity.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Militares/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Adulto , Bélgica/epidemiologia , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Surtos de Doenças , Humanos , Masculino , Epidemiologia Molecular , Níger/epidemiologia , Pandemias , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2 , Testes Sorológicos , Carga Viral , Adulto Jovem
8.
F1000Res ; 9: 1296, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33564397

RESUMO

The JRC COVID-19 In Vitro Diagnostic Devices and Test Methods Database, aimed to collect in a single place all publicly available information on performance of CE-marked in vitro diagnostic medical devices (IVDs) as well as in house laboratory-developed devices and related test methods for COVID-19, is here presented. The database, manually curated and regularly updated, has been developed as a follow-up to the Communication from the European Commission "Guidelines on in vitro diagnostic tests and their performance" of 15 April 2020 and is freely accessible at https://covid-19-diagnostics.jrc.ec.europa.eu/.


Assuntos
COVID-19/diagnóstico , Bases de Dados Factuais , Kit de Reagentes para Diagnóstico , União Europeia , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-30985273

RESUMO

Whereas the dramatic environmental impact of plastic waste rightfully receives considerable attention by scientists, policy makers and public in general, the human health impact of micro- and nanoplastics contamination of our food and beverages remains largely unknown. Indeed, most studies aim at understanding the environmental impact rather than the human health impact of a possible exposure to micro- and nanoplastics. In addition, these papers generally lack a methodological, standardised approach. Furthermore, some studies focus on the damage to and contamination level of animal species collected from the wild environment, and others investigate the rate and biology of microplastic uptake of animals fed with microplastics in laboratory. This review aims at understanding human exposure. Since there is, with few exceptions, no evidence available on the presence of micro- and nanoplastics in a normal diet, this study takes an indirect approach and analyses peer-reviewed publications since 2010 that document the presence of micro- and nanoplastics in those animals (more than 200 species) and food products that are part of the human food chain and that may thus contribute directly or indirectly to the uptake of micro- and nanoplastics via the human diet. It also addresses the question of the definitions, the methodologies and the quality criteria applied to obtain the reported results. This review suggests that, beyond a few estimations and comparisons, precise data to assess the exact exposure of humans to micro- and nanoplastics through their diet cannot be produced until standardised methods and definitions are available.


Assuntos
Contaminação de Alimentos/análise , Abastecimento de Alimentos , Plásticos/análise , Animais , Humanos
10.
F1000Res ; 72018.
Artigo em Inglês | MEDLINE | ID: mdl-30026930

RESUMO

Next-Generation Sequencing (NGS) technologies are expected to play a crucial role in the surveillance of infectious diseases, with their unprecedented capabilities for the characterisation of genetic information underlying the virulence and antimicrobial resistance (AMR) properties of microorganisms.  In the implementation of any novel technology for regulatory purposes, important considerations such as harmonisation, validation and quality assurance need to be addressed.  NGS technologies pose unique challenges in these regards, in part due to their reliance on bioinformatics for the processing and proper interpretation of the data produced.  Well-designed benchmark resources are thus needed to evaluate, validate and ensure continued quality control over the bioinformatics component of the process.  This concept was explored as part of a workshop on "Next-generation sequencing technologies and antimicrobial resistance" held October 4-5 2017.   Challenges involved in the development of such a benchmark resource, with a specific focus on identifying the molecular determinants of AMR, were identified. For each of the challenges, sets of unsolved questions that will need to be tackled for them to be properly addressed were compiled. These take into consideration the requirement for monitoring of AMR bacteria in humans, animals, food and the environment, which is aligned with the principles of a "One Health" approach.


Assuntos
Antibacterianos/farmacologia , Biologia Computacional/métodos , Farmacorresistência Bacteriana/genética , Sequenciamento de Nucleotídeos em Larga Escala , Benchmarking
11.
Pharm Res ; 32(7): 2173-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25585954

RESUMO

The worldwide antibiotic crisis has led to a renewed interest in phage therapy. Since time immemorial phages control bacterial populations on Earth. Potent lytic phages against bacterial pathogens can be isolated from the environment or selected from a collection in a matter of days. In addition, phages have the capacity to rapidly overcome bacterial resistances, which will inevitably emerge. To maximally exploit these advantage phages have over conventional drugs such as antibiotics, it is important that sustainable phage products are not submitted to the conventional long medicinal product development and licensing pathway. There is a need for an adapted framework, including realistic production and quality and safety requirements, that allows a timely supplying of phage therapy products for 'personalized therapy' or for public health or medical emergencies. This paper enumerates all phage therapy product related quality and safety risks known to the authors, as well as the tests that can be performed to minimize these risks, only to the extent needed to protect the patients and to allow and advance responsible phage therapy and research.


Assuntos
Infecções Bacterianas , Bacteriófagos/crescimento & desenvolvimento , Terapia Biológica , Farmacorresistência Bacteriana Múltipla , Infecções Bacterianas/microbiologia , Infecções Bacterianas/terapia , Bacteriófagos/isolamento & purificação , Terapia Biológica/efeitos adversos , Terapia Biológica/normas , Terapia Biológica/tendências , Humanos
12.
PLoS One ; 7(6): e39287, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22761753

RESUMO

Escherichia coli is a group of bacteria which has raised a lot of safety concerns in recent years. Five major intestinal pathogenic groups have been recognized amongst which the verocytotoxin or shiga-toxin (stx1 and/or stx2) producing E. coli (VTEC or STEC respectively) have received a lot of attention recently. Indeed, due to the high number of outbreaks related to VTEC strains, the European Food Safety Authority (EFSA) has requested the monitoring of the "top-five" serogroups (O26, O103, O111, O145 and O157) most often encountered in food borne diseases and addressed the need for validated VTEC detection methods. Here we report the development of a set of intercalating dye Real-time PCR methods capable of rapidly detecting the presence of the toxin genes together with intimin (eae) in the case of VTEC, or aggregative protein (aggR), in the case of the O104:H4 strain responsible for the outbreak in Germany in 2011. All reactions were optimized to perform at the same annealing temperature permitting the multiplex application in order to minimize the need of material and to allow for high-throughput analysis. In addition, High Resolution Melting (HRM) analysis allowing the discrimination among strains possessing similar virulence traits was established. The development, application to food samples and the flexibility in use of the methods are thoroughly discussed. Together, these Real-time PCR methods facilitate the detection of VTEC in a new highly efficient way and could represent the basis for developing a simple pathogenic E. coli platform.


Assuntos
Escherichia coli/isolamento & purificação , Doenças Transmitidas por Alimentos/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Sensibilidade e Especificidade
13.
Mol Ecol Resour ; 12(5): 810-21, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22805239

RESUMO

The cultivation of genetically modified (GM) crops has raised numerous concerns in the European Union and other parts of the world about their environmental and economic impact. Especially outcrossing of genetically modified organisms (GMO) was from the beginning a critical issue as airborne pollen has been considered an important way of GMO dispersal. Here, we investigate the use of airborne pollen sampling combined with microscopic analysis and molecular PCR analysis as an approach to monitor GM maize cultivations in a specific area. Field trial experiments in the European Union and South America demonstrated the applicability of the approach under different climate conditions, in rural and semi-urban environment, even at very low levels of airborne pollen. The study documents in detail the sampling of GM pollen, sample DNA extraction and real-time PCR analysis. Our results suggest that this 'GM pollen monitoring by bioaerosol sampling and PCR screening' approach might represent an useful aid in the surveillance of GM-free areas, centres of origin and natural reserves.


Assuntos
Material Particulado/isolamento & purificação , Plantas Geneticamente Modificadas , Pólen/classificação , Pólen/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Zea mays/classificação , Zea mays/genética , União Europeia , Microscopia/métodos , Biologia Molecular/métodos , Sensibilidade e Especificidade , América do Sul , Manejo de Espécimes/métodos
14.
Appl Environ Microbiol ; 77(19): 6954-63, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21856838

RESUMO

European Commission regulation 2073/2005 on the microbiological criteria for food requires that Escherichia coli is monitored as an indicator of hygienic conditions. Since verocytotoxigenic E. coli (VTEC) strains often cause food-borne infections by the consumption of raw food, the Biological Hazards (BIOHAZ) panel of the European Food Safety Authority (EFSA) recommended their monitoring in food as well. In particular, VTEC strains belonging to serogroups such as O26, O103, O111, O145, and O157 are known causative agents of several human outbreaks. Eight real-time PCR methods for the detection of E. coli toxin genes and their variants (stx(1), stx(2)), the intimin gene (eae), and five serogroup-specific genes have been proposed by the European Reference Laboratory for VTEC (EURL-VTEC) as a technical specification to the European Normalization Committee (CEN TC275/WG6). Here we applied a "modular approach" to the in-house validation of these PCR methods. The modular approach subdivides an analytical process into separate parts called "modules," which are independently validated based on method performance criteria for a limited set of critical parameters. For the VTEC real-time PCR module, the following parameters are being assessed: specificity, dynamic range, PCR efficiency, and limit of detection (LOD). This study describes the modular approach for the validation of PCR methods to be used in food microbiology, using single-target plasmids as positive controls and showing their applicability with food matrices.


Assuntos
Técnicas Bacteriológicas/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/isolamento & purificação , Infecções por Escherichia coli/prevenção & controle , Microbiologia de Alimentos , Humanos , Sensibilidade e Especificidade , Escherichia coli Shiga Toxigênica/genética
15.
BMC Biotechnol ; 10: 55, 2010 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-20687918

RESUMO

BACKGROUND: The modular approach to analysis of genetically modified organisms (GMOs) relies on the independence of the modules combined (i.e. DNA extraction and GM quantification). The validity of this assumption has to be proved on the basis of specific performance criteria. RESULTS: An experiment was conducted using, as a reference, the validated quantitative real-time polymerase chain reaction (PCR) module for detection of glyphosate-tolerant Roundup Ready(R) GM soybean (RRS). Different DNA extraction modules (CTAB, Wizard and Dellaporta), were used to extract DNA from different food/feed matrices (feed, biscuit and certified reference material [CRM 1%]) containing the target of the real-time PCR module used for validation. Purity and structural integrity (absence of inhibition) were used as basic criteria that a DNA extraction module must satisfy in order to provide suitable template DNA for quantitative real-time (RT) PCR-based GMO analysis. When performance criteria were applied (removal of non-compliant DNA extracts), the independence of GMO quantification from the extraction method and matrix was statistically proved, except in the case of Wizard applied to biscuit. A fuzzy logic-based procedure also confirmed the relatively poor performance of the Wizard/biscuit combination. CONCLUSIONS: For RRS, this study recognises that modularity can be generally accepted, with the limitation of avoiding combining highly processed material (i.e. biscuit) with a magnetic-beads system (i.e. Wizard).


Assuntos
Análise de Alimentos/métodos , Glycine max/genética , Plantas Geneticamente Modificadas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Ração Animal/análise , DNA de Plantas/análise , DNA de Plantas/isolamento & purificação , Alimentos Geneticamente Modificados , Projetos Piloto
17.
Anal Bioanal Chem ; 396(6): 1991-2002, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19876618

RESUMO

The steady rate of development and diffusion of genetically modified plants and their increasing diversification of characteristics, genes and genetic control elements poses a challenge in analysis of genetically modified organisms (GMOs). It is expected that in the near future the picture will be even more complex. Traditional approaches, mostly based on the sequential detection of one target at a time, or on a limited multiplexing, allowing only a few targets to be analysed at once, no longer meet the testing requirements. Along with new analytical technologies, new approaches for the detection of GMOs authorized for commercial purposes in various countries have been developed that rely on (1) a smart and accurate strategy for target selection, (2) the use of high-throughput systems or platforms for the detection of multiple targets and (3) algorithms that allow the conversion of analytical results into an indication of the presence of individual GMOs potentially present in an unknown sample. This paper reviews the latest progress made in GMO analysis, taking examples from the most recently developed strategies and tools, and addresses some of the critical aspects related to these approaches.


Assuntos
Técnicas Genéticas , Ensaios de Triagem em Larga Escala/métodos , Plantas Geneticamente Modificadas/genética
18.
Transgenic Res ; 19(1): 57-65, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19533405

RESUMO

This paper illustrates the advantages that a fuzzy-based aggregation method could bring into the validation of a multiplex method for GMO detection (DualChip GMO kit, Eppendorf). Guidelines for validation of chemical, bio-chemical, pharmaceutical and genetic methods have been developed and ad hoc validation statistics are available and routinely used, for in-house and inter-laboratory testing, and decision-making. Fuzzy logic allows summarising the information obtained by independent validation statistics into one synthetic indicator of overall method performance. The microarray technology, introduced for simultaneous identification of multiple GMOs, poses specific validation issues (patterns of performance for a variety of GMOs at different concentrations). A fuzzy-based indicator for overall evaluation is illustrated in this paper, and applied to validation data for different genetically modified elements. Remarks were drawn on the analytical results. The fuzzy-logic based rules were shown to be applicable to improve interpretation of results and facilitate overall evaluation of the multiplex method.


Assuntos
Lógica Fuzzy , Técnicas Genéticas/estatística & dados numéricos , Organismos Geneticamente Modificados/genética , Estudos de Validação como Assunto , Algoritmos , Animais , Coleta de Dados/métodos , Coleta de Dados/estatística & dados numéricos , Interpretação Estatística de Dados , Análise em Microsséries/métodos , Análise em Microsséries/estatística & dados numéricos
19.
J Agric Food Chem ; 57(8): 3156-63, 2009 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-19368351

RESUMO

In March 2005, U.S. authorities informed the European Commission of the inadvertent release of unauthorized maize GM event Bt10 in their market and subsequently the grain channel. In the United States measures were taken to eliminate Bt10 from seed and grain supplies; in the European Union an embargo for maize gluten and brewer's grain import was implemented unless certified of Bt10 absence with a Bt10-specific PCR detection method. With the aim of assessing the validity of the Bt10 detection method, an in-depth analysis of the molecular organization of the genetic modification of this event was carried out by both the company Syngenta, who produced the event, and the European Commission Joint Research Centre, who validated the detection method. Using a variety of molecular analytical tools, both organizations found the genetic modification of event Bt10 to be very complex in structure, with rearrangements, inversions, and multiple copies of the structural elements (cry1Ab, pat, and the amp gene), interspersed with small genomic maize fragments. Southern blot analyses demonstrated that all Bt10 elements were found tightly linked on one large fragment, including the region that would generate the event-specific PCR amplicon of the Bt10 detection method. This study proposes a hypothetical map of the insert of event Bt10 and concludes that the validated detection method for event Bt10 is fit for its purpose.


Assuntos
Proteínas de Bactérias/genética , DNA de Plantas/análise , DNA Recombinante/análise , Endotoxinas/genética , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas/genética , Sementes/genética , Zea mays/genética , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/análise , Southern Blotting , Endotoxinas/análise , Europa (Continente) , Biblioteca Gênica , Proteínas Hemolisinas/análise , Legislação sobre Alimentos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Estados Unidos
20.
J Agric Food Chem ; 57(9): 3525-32, 2009 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-19326953

RESUMO

One rice ( Oryza sativa ) gene, sucrose phosphate synthase (SPS), has been proven to be a suitable endogenous reference gene for genetically modified (GM) rice detection in a previous study. Herein are the reported results of an international collaborative ring trial for validation of the SPS gene as an endogenous reference gene and its optimized qualitative and quantitative polymerase chain reaction (PCR) systems. A total of 12 genetically modified organism (GMO) detection laboratories from seven countries participated in the ring trial and returned their results. The validated results confirmed the species specificity of the method through testing 10 plant genomic DNAs, low heterogeneity, and a stable single-copy number of the rice SPS gene among 7 indica varieties and 5 japonica varieties. The SPS qualitative PCR assay was validated with a limit of detection (LOD) of 0.1%, which corresponded to about 230 copies of haploid rice genomic DNA, while the limit of quantification (LOQ) for the quantitative PCR system was about 23 copies of haploid rice genomic DNA, with acceptable PCR efficiency and linearity. Furthermore, the bias between the test and true values of eight blind samples ranged from 5.22 to 26.53%. Thus, we believe that the SPS gene is suitable for use as an endogenous reference gene for the identification and quantification of GM rice and its derivates.


Assuntos
Glucosiltransferases/genética , Oryza/genética , Plantas Geneticamente Modificadas/genética , DNA de Plantas/análise , Glucosiltransferases/metabolismo , Cooperação Internacional , Plantas Geneticamente Modificadas/classificação , Plantas Geneticamente Modificadas/enzimologia , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Sementes/genética , Especificidade da Espécie , Especificidade por Substrato
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