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1.
OMICS ; 25(8): 484-494, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34255557

RESUMEN

Pandemics and environmental crises evident from the first two decades of the 21st century call for methods innovation in biosurveillance and early detection of risk signals in planetary ecosystems. In crises conditions, conventional methods in public health, biosecurity, and environmental surveillance do not work well. In addition, the standard laboratory amenities and procedures may become unavailable, irrelevant, or simply not feasible, for example, owing to disruptions in logistics and process supply chains. The COVID-19 pandemic has been a wakeup call in this sense to reintroduce point-of-need diagnostics with an eye to limited resource settings and biosurveillance solutions. We report here a methodology innovation, a fast, scalable, and alkaline DNA extraction pipeline for emergency microbiomics biosurveillance. We believe that the presented methodology is well poised for effective, resilient, and anticipatory responses to future pandemics and ecological crises while contributing to microbiome science and point-of-need diagnostics in nonelective emergency contexts. The alkaline DNA extraction pipeline can usefully expand the throughput in emergencies by deployment or to allow backup in case of instrumentation failure in vital facilities. The need for distributed public health genomics surveillance is increasingly evident in the 21st century. This study makes a contribution to these ends broadly, and for future pandemic preparedness in particular. We call for innovation in biosurveillance methods that remain important existentially on a planet under pressure from unchecked human growth and breach of the boundaries between human and nonhuman animal habitats.


Asunto(s)
Biovigilancia/métodos , ADN/aislamiento & purificación , Técnicas Microbiológicas , Vigilancia en Salud Pública/métodos , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Técnicas Genéticas/economía , Humanos , Técnicas Microbiológicas/economía , Plantas/microbiología
2.
Trends Genet ; 37(9): 776-779, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34016451

RESUMEN

Next-generation sequencing (NGS) has identified disease hallmarks and catalogued a vast reservoir of genetic information from humans and other species. Precise nucleotide-interrogation properties of clustered regularly interspaced short palindromic repeats (CRISPR) proteins have been harnessed to rapidly identify DNA-RNA signatures for diverse applications, bypassing the cost and turnaround times associated with diagnostic NGS.


Asunto(s)
Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Técnicas Genéticas , Técnicas de Diagnóstico Molecular/métodos , Biomarcadores de Tumor/genética , Proteínas Asociadas a CRISPR/genética , ADN , Técnicas Genéticas/economía , Humanos , Plantas Medicinales/genética , ARN , Tuberculosis/diagnóstico , Tuberculosis/microbiología
3.
Clin Lab ; 65(11)2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31710449

RESUMEN

BACKGROUND: Genomic studies facilitate comprehension of the pathophysiology, diagnosis, and treatment of chronic diseases. Such studies require sufficient and good quality DNA isolated from a large number of blood samples. This study attempts to obtain a high-quality genomic DNA isolated from a large number of blood samples using a simple and cheap method. METHODS: The EasyPure® Genomic DNA Kit (Transgen Biotech) was modified to increase the amount of DNA recovery: a few steps and two additional column elutions were added to the original manufacturer´s procedure. RESULTS: The amount of DNA isolated from frozen blood samples increased by an average of 56%. Its 260/280 ratio and electrophoretic mobility properties make it suitable for genomic studies. CONCLUSIONS: A relatively low-cost commercial column and a simple modification of the manufacturer´s protocol, provided a simple and cheap procedure to isolate high-quality DNA from a large number of blood samples suitable for genomic studies.


Asunto(s)
Células Sanguíneas/química , Recolección de Muestras de Sangre/economía , ADN/aislamiento & purificación , Técnicas Genéticas/economía , Análisis Costo-Beneficio , ADN/sangre , Humanos
4.
Arch Pathol Lab Med ; 143(5): 628-633, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30576239

RESUMEN

CONTEXT.­: Molecular analysis of lung adenocarcinoma for therapeutically important genes is standard of practice, with multiple professional organizations recommending testing of all adenocarcinomas for mutations in EGFR, ALK, and ROS1. Some organizations recommend analyzing these genes in association with a panel. Few data exist as to optimal testing method or optimal sequence of testing from a cost perspective. OBJECTIVE.­: To determine which order of gene testing was least costly and whether sequential, small panel, or next-generation sequencing (NGS) was cheapest. DESIGN.­: Recent recommendations propose a set of essential molecular tests (EGFR, ALK, and ROS1) and an optional set of molecular tests that may be useful for selection of clinical trials. We compared the costs of different testing sequencing strategies for both the 3 essential genes and for 5 optimal genes. Testing costs were determined by a survey of prices from large laboratories. The strategy most frequently rated as the lowest cost strategy was designated the optimal testing strategy. RESULTS.­: Sequential testing of the essential genes in the order EGFR-ROS1-ALK was optimal from a cost perspective. The expected cost of sequential testing was $2227 (95% CI, $1733-$2794). The cost of NGS was $2500. The expected cost per positive result was $11,362 using this strategy. CONCLUSIONS.­: Molecular testing of lung adenocarcinomas for the set of 3 essential genes and 5 optional genes can be performed by a variety of methods and in a variety of sequences. From a cost perspective, sequential testing in the order EGFR, ROS1, then ALK is optimal. NGS would be competitive if the price was less than $2200. NGS is optimal if testing for the 3 essential genes will be followed by testing for the 5 optional genes. NGS testing is optimal if the clinician plans to test both essential and optional genes.


Asunto(s)
Adenocarcinoma del Pulmón/genética , Técnicas Genéticas/economía , Pruebas Genéticas/economía , Neoplasias Pulmonares/genética , Costos y Análisis de Costo , Humanos
5.
ACS Synth Biol ; 7(3): 807-813, 2018 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-29486117

RESUMEN

MicroRNAs have been reported as related to multiple diseases and have potential applications in diagnosis and therapeutics. However, detection of miRNAs remains improvable, given their complexity, high cost, and low sensitivity as of currently. In this study, we attempt to build a novel platform that detects miRNAs at low cost and high efficacy. This detection system contains isothermal amplification, detecting and reporting process based on rolling circle amplification, CRISPR-Cas9, and split-horseradish peroxidase techniques. It is able to detect trace amount of miRNAs from samples with mere single-base specificity. Moreover, we demonstrated that such scheme can effectively detect target miRNAs in clinical serum samples and significantly distinguish patients of non-small cell lung cancer from healthy volunteers by detecting the previously reported biomarker: circulating let-7a. As the first to use CRISPR-Cas9 in miRNA detection, this method is a promising approach capable of being applied in screening, diagnosing, and prognosticating of multiple diseases.


Asunto(s)
Sistemas CRISPR-Cas/genética , Costos y Análisis de Costo , Técnicas Genéticas/economía , MicroARNs/análisis , MicroARNs/economía , Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/genética , Peroxidasa de Rábano Silvestre/metabolismo , Humanos , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/genética , MicroARNs/genética , Sondas ARN/metabolismo
6.
Lett Appl Microbiol ; 66(1): 32-37, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29117447

RESUMEN

The aim of this work was to evaluate a fungal DNA extraction procedure with the lowest inputs in terms of time as well as of expensive and toxic chemicals, but able to consistently produce genomic DNA of good quality for PCR purposes. Two types of fungal biological material were tested - mycelium and conidia - combined with two protocols for DNA extraction using Sodium Dodecyl Sulphate (SDS) and Cetyl Trimethyl Ammonium Bromide as extraction buffers and glass beads for mechanical disruption of cell walls. Our results showed that conidia and SDS buffer was the combination that lead to the best DNA quality and yield, with the lowest variation between samples. This study clearly demonstrates that it is possible to obtain high yield and pure DNA from pigmented conidia without the use of strong cell disrupting procedures and of toxic reagents. SIGNIFICANCE AND IMPACT OF THE STUDY: There are numerous methods for DNA extraction from fungi. Some rely on expensive commercial kits and/or equipments, unavailable for many laboratories, or make use of toxic chemicals such as chloroform, phenol and mercaptoethanol. This study clearly demonstrates that it is possible to obtain high yields of pure DNA from pigmented conidia without the use of strong and expensive cell disrupting procedures and of toxic reagents. The method herein described is simultaneously inexpensive and adequate to DNA extraction from several different types of fungi.


Asunto(s)
ADN de Hongos/genética , Equipos y Suministros/economía , Hongos/genética , Técnicas Genéticas/instrumentación , Pared Celular/química , ADN de Hongos/aislamiento & purificación , Hongos/aislamiento & purificación , Técnicas Genéticas/economía , Indicadores y Reactivos/toxicidad , Laboratorios/economía , Reacción en Cadena de la Polimerasa , Esporas Fúngicas/química
7.
Cell ; 171(4): 966-979.e18, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-29056345

RESUMEN

Protein aggregation is a hallmark of many diseases but also underlies a wide range of positive cellular functions. This phenomenon has been difficult to study because of a lack of quantitative and high-throughput cellular tools. Here, we develop a synthetic genetic tool to sense and control protein aggregation. We apply the technology to yeast prions, developing sensors to track their aggregation states and employing prion fusions to encode synthetic memories in yeast cells. Utilizing high-throughput screens, we identify prion-curing mutants and engineer "anti-prion drives" that reverse the non-Mendelian inheritance pattern of prions and eliminate them from yeast populations. We extend our technology to yeast RNA-binding proteins (RBPs) by tracking their propensity to aggregate, searching for co-occurring aggregates, and uncovering a group of coalescing RBPs through screens enabled by our platform. Our work establishes a quantitative, high-throughput, and generalizable technology to study and control diverse protein aggregation processes in cells.


Asunto(s)
Técnicas Genéticas , Priones/genética , Ingeniería Genética , Técnicas Genéticas/economía , Proteínas de Unión al ARN/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Biología Sintética/métodos , Factores de Escisión y Poliadenilación de ARNm/metabolismo
8.
Transgenic Res ; 26(3): 399-409, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28314980

RESUMEN

Canada is the world's largest producer and exporter of flaxseed. In 2009, DNA from deregistered genetically modified (GM) CDC Triffid was detected in a shipment of Canadian flaxseed exported to Europe, causing a large decrease in the amount of flax planted in Canada and a major shift in export markets. The flax industry in Canada undertook major changes to ensure the removal of transgenic flax from the supply chain. To demonstrate compliance, Canada adopted a protocol involving testing grain samples (post-harvest) using an RT-PCR test for the construct found in CDC Triffid. Efforts to remove the presence of GM flax from the value chain included reconstituting major flax varieties from GM-free plants. The reconstituted varieties represented the majority of planting seed in 2014. This study re-evaluates GM flax presence in Canadian grain stocks for an updated dataset (2009-2015) using a previously described simulation model to estimate low-level GM presence. Additionally, losses to the Canadian economy resulting from the reduction in flax production and export opportunities, costs associated with reconstituting major flax varieties, and testing for the presence of GM flax along the flax value chain are estimated.


Asunto(s)
Agricultura/legislación & jurisprudencia , Lino/genética , Plantas Modificadas Genéticamente/genética , Agricultura/economía , Canadá , Unión Europea , Reacciones Falso Positivas , Técnicas Genéticas/economía
9.
Plant Cell Rep ; 35(9): 1987-90, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27447893

RESUMEN

Alfalfa is the most important forage legume worldwide. However, similar to other minor forage crops, it is usually harvested along with weeds, which decrease its nutrient quality and thus reduce its high value in the market. In addition, weeds reduce alfalfa yield by about 50 %. Although weeds are the limiting factor for alfalfa production, little progress has been made in the incorporation of herbicide-tolerant traits into commercial alfalfa. This is partially due to the high times and costs needed for the production of vast numbers of transgenic alfalfa events as an empirical approach to bypass the random transgenic silencing and for the identification of an event with optimal transgene expression. In this focus article, we report the complete sequence of pPZP200BAR and the extremely high efficiency of this binary vector in alfalfa transformation, opening the way for rapid and inexpensive production of transgenic events for alfalfa improvement public programs.


Asunto(s)
Costos y Análisis de Costo , Biblioteca de Genes , Técnicas Genéticas/economía , Vectores Genéticos/metabolismo , Medicago sativa/genética , Análisis de Secuencia de ADN , Plantas Modificadas Genéticamente , Plásmidos/metabolismo , Factores de Tiempo , Transformación Genética
11.
Zebrafish ; 13(6): 537-540, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27057799

RESUMEN

Genetic manipulations are a vital instrument for the study of embryonic development where to understand how genes work, it is necessary to provoke a loss or gain of function of a particular gene in a spatial and temporal manner. In the zebrafish embryo, the Hsp70 promoter is the most commonly used tool to induce a transient global gene expression of a desired gene, in a temporal manner. However, Hsp70-driven global gene induction presents caveats when studying gene function in a tissue of interest as gene induction in the whole embryo can lead to cell-autonomous and non-cell-autonomous phenotypes. In the current article, we describe an innovative and cost effective protocol to activate Hsp70-dependent expression in a small subset of cells in the zebrafish embryo, by utilizing a localized infrared (IR) laser. Our IR laser set up can be incorporated to any microscope platform without the requirement for expensive equipment. Furthermore, our protocol allows for controlled localized induction of specific proteins under the control of the hsp70 promoter in small subsets of cells. We use the migrating zebrafish sensory lateral line primordium as a model, because of its relative simplicity and experimental accessibility; however, this technique can be applied to any tissue in the zebrafish embryo.


Asunto(s)
Desarrollo Embrionario/efectos de la radiación , Regulación del Desarrollo de la Expresión Génica , Técnicas Genéticas , Respuesta al Choque Térmico/genética , Calor , Pez Cebra/fisiología , Animales , Desarrollo Embrionario/genética , Técnicas Genéticas/economía , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Rayos Infrarrojos/efectos adversos , Rayos Láser , Regiones Promotoras Genéticas , Pez Cebra/embriología , Pez Cebra/genética
13.
Biochemistry (Mosc) ; 80(11): 1478-84, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26615439

RESUMEN

Here we report a rapid and cost-effective method for the extraction of total DNA from herbarium specimens up to 50-90-year-old. The method takes about 2 h, uses AMPure XP magnetic beads diluted by PEG-8000- containing buffer, and does not require use of traditional volatile components like chloroform, phenol, and liquid nitrogen. It yields up to 4 µg of total nucleic acid with high purity from about 30 mg of dry material. The quality of the extracted DNA was tested by PCR amplification of 5S rRNA and rbcL genes (nuclear and chloroplast DNA markers) and compared against the traditional chloroform/isoamyl alcohol method. Our results demonstrate that the use of the magnetic beads is crucial for extraction of DNA suitable for subsequent PCR from herbarium samples due to the decreasing inhibitor concentrations, reducing short fragments of degraded DNA, and increasing median DNA fragment sizes.


Asunto(s)
Asteraceae/química , Asteraceae/genética , Botánica/métodos , ADN de Plantas/aislamiento & purificación , Técnicas Genéticas , Cloroformo/química , ADN de Plantas/análisis , ADN de Plantas/metabolismo , Fluorometría , Técnicas Genéticas/economía , Pentanoles/química , Hojas de la Planta/química , Hojas de la Planta/genética , Polietilenglicoles/química , Reacción en Cadena de la Polimerasa , ARN Ribosómico 5S/genética , Ribulosa-Bifosfato Carboxilasa/genética , Espectrofotometría
14.
BMC Biol ; 13: 88, 2015 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-26510635

RESUMEN

We believe that replicating studies in ecology and evolution is extremely valuable, but replication within species and systems is troublingly rare, and even 'quasi-replications' in different systems are often insufficient. We make a case for supporting multiple types of replications and point out that the current incentive structure needs to change if ecologists and evolutionary biologist are to value scientific replication sufficiently.


Asunto(s)
Evolución Biológica , Ecología/economía , Ecología/métodos , Técnicas Genéticas , Proyectos de Investigación , Análisis Costo-Beneficio , Técnicas Genéticas/economía
15.
Anal Chem ; 87(15): 7872-9, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26125635

RESUMEN

The 2009 Influenza A (H1N1) pandemic disproportionately affected the developing world and highlighted the key inadequacies of traditional diagnostic methods that make them unsuitable for use in resource-limited settings, from expensive equipment and infrastructure requirements to unacceptably long turnaround times. While rapid immunoassay diagnostic tests were much less costly and more context-appropriate, they suffered from drastically low sensitivities and high false negative rates. An accurate, sensitive, and specific molecular diagnostic that is also rapid, low-cost, and independent of laboratory infrastructure is needed for effective point-of-care detection and epidemiological control in these developing regions. We developed a paper-based assay that allows for the extraction and purification of RNA directly from human clinical nasopharyngeal specimens through a poly(ether sulfone) paper matrix, H1N1-specific in situ isothermal amplification directly within the same paper matrix, and immediate visual detection on lateral flow strips. The complete sample-to-answer assay can be performed at the point-of-care in just 45 min, without the need for expensive equipment or laboratory infrastructure, and it has a clinically relevant viral load detection limit of 10(6) copies/mL, offering a 10-fold improvement over current rapid immunoassays.


Asunto(s)
Técnicas Genéticas , Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/diagnóstico , ARN/genética , Técnicas Genéticas/economía , Técnicas Genéticas/instrumentación , Técnicas Genéticas/normas , Humanos , Subtipo H1N1 del Virus de la Influenza A/química , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Límite de Detección , Papel , Sistemas de Atención de Punto , ARN/química
16.
Am J Hum Biol ; 27(3): 295-303, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25711975

RESUMEN

The study of epigenetics, or chemical modifications to the genome that may alter gene expression, is a growing area of interest for social scientists. Anthropologists and human biologists are interested in epigenetics specifically, as it provides a potential link between the environment and the genome, as well as a new layer of complexity for the study of human biological variation. In pace with the rapid increase in interest in epigenetic research, the range of methods has greatly expanded over the past decade. The primary objective of this article is to provide an overview of the current methods for assaying DNA methylation, the most commonly studied epigenetic modification. We will address considerations for all steps required to plan and conduct an analysis of DNA methylation, from appropriate sample collection, to the most commonly used methods for laboratory analyses of locus-specific and genome-wide approaches, and recommendations for statistical analyses. Key challenges in the study of DNA methylation are also discussed, including tissue specificity, the stability of measures, timing of sample collection, statistical considerations, batch effects, and challenges related to analysis and interpretation of data. Our hope is that this review serves as a primer for anthropologists and human biologists interested in incorporating epigenetic data into their research programs.


Asunto(s)
Metilación de ADN , Epigenómica/métodos , Técnicas Genéticas/instrumentación , Epigénesis Genética/fisiología , Expresión Génica/fisiología , Técnicas Genéticas/economía , Estudio de Asociación del Genoma Completo/economía , Estudio de Asociación del Genoma Completo/instrumentación , Humanos , Manejo de Especímenes/métodos
17.
Health Technol Assess ; 18(62): 1-132, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25314637

RESUMEN

BACKGROUND: Bowel cancer is the third most common cancer in the UK. Most bowel cancers are initially treated with surgery, but around 17% spread to the liver. When this happens, sometimes the liver tumour can be treated surgically, or chemotherapy may be used to shrink the tumour to make surgery possible. Kirsten rat sarcoma viral oncogene (KRAS) mutations make some tumours less responsive to treatment with biological therapies such as cetuximab. There are a variety of tests available to detect these mutations. These vary in the specific mutations that they detect, the amount of mutation they detect, the amount of tumour cells needed, the time to give a result, the error rate and cost. OBJECTIVES: To compare the performance and cost-effectiveness of KRAS mutation tests in differentiating adults with metastatic colorectal cancer whose metastases are confined to the liver and are unresectable and who may benefit from first-line treatment with cetuximab in combination with standard chemotherapy from those who should receive standard chemotherapy alone. DATA SOURCES: Thirteen databases, including MEDLINE and EMBASE, research registers and conference proceedings were searched to January 2013. Additional data were obtained from an online survey of laboratories participating in the UK National External Quality Assurance Scheme pilot for KRAS mutation testing. METHODS: A systematic review of the evidence was carried out using standard methods. Randomised controlled trials were assessed for quality using the Cochrane risk of bias tool. Diagnostic accuracy studies were assessed using the QUADAS-2 tool. There were insufficient data for meta-analysis. For accuracy studies we calculated sensitivity and specificity together with 95% confidence intervals (CIs). Survival data were summarised as hazard ratios and tumour response data were summarised as relative risks, with 95% CIs. The health economic analysis considered the long-term costs and quality-adjusted life-years associated with different tests followed by treatment with standard chemotherapy or cetuximab plus standard chemotherapy. The analysis took a 'no comparator' approach, which implies that the cost-effectiveness of each strategy will be presented only compared with the next most cost-effective strategy. The de novo model consisted of a decision tree and Markov model. RESULTS: The online survey indicated no differences between tests in batch size, turnaround time, number of failed samples or cost. The literature searches identified 7903 references, of which seven publications of five studies were included in the review. Two studies provided data on the accuracy of KRAS mutation testing for predicting response to treatment in patients treated with cetuximab plus standard chemotherapy. Four RCTs provided data on the clinical effectiveness of cetuximab plus standard chemotherapy compared with that of standard chemotherapy in patients with KRAS wild-type tumours. There were no clear differences in the treatment effects reported by different studies, regardless of which KRAS mutation test was used to select patients. In the 'linked evidence' analysis the Therascreen KRAS RGQ PCR Kit (QIAGEN) was more expensive but also more effective than pyrosequencing or direct sequencing, with an incremental cost-effectiveness ratio of £17,019 per quality-adjusted life-year gained. In the 'assumption of equal prognostic value' analysis the total costs associated with the various testing strategies were similar. LIMITATIONS: The results assume that the differences in outcomes between the trials were solely the result of the different mutation tests used to distinguish between patients; this assumption ignores other factors that might explain this variation. CONCLUSIONS: There was no strong evidence that any one KRAS mutation test was more effective or cost-effective than any other test. STUDY REGISTRATION: PROSPERO CRD42013003663. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Técnicas Genéticas/economía , Proteínas Proto-Oncogénicas/genética , Proteínas ras/genética , Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos , Cetuximab , Neoplasias Colorrectales/patología , Análisis Costo-Beneficio , Humanos , Neoplasias Hepáticas/secundario , Cadenas de Markov , Mutación , Proteínas Proto-Oncogénicas p21(ras) , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
Environ Int ; 64: 124-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24394589

RESUMEN

The debate over the suitability of molecular biological methods for the enumeration of regulatory microbial parameters (e.g. Faecal Indicator Organisms [FIOs]) in bathing waters versus the use of traditional culture-based methods is of current interest to regulators and the science community. Culture-based methods require a 24-48hour turn-around time from receipt at the laboratory to reporting, whilst quantitative molecular tools provide a more rapid assay (approximately 2-3h). Traditional culturing methods are therefore often viewed as slow and 'out-dated', although they still deliver an internationally 'accepted' evidence-base. In contrast, molecular tools have the potential for rapid analysis and their operational utility and associated limitations and uncertainties should be assessed in light of their use for regulatory monitoring. Here we report on the recommendations from a series of international workshops, chaired by a UK Working Group (WG) comprised of scientists, regulators, policy makers and other stakeholders, which explored and interrogated both molecular (principally quantitative polymerase chain reaction [qPCR]) and culture-based tools for FIO monitoring under the European Bathing Water Directive. Through detailed analysis of policy implications, regulatory barriers, stakeholder engagement, and the needs of the end-user, the WG identified a series of key concerns that require critical appraisal before a potential shift from culture-based approaches to the employment of molecular biological methods for bathing water regulation could be justified.


Asunto(s)
Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/normas , Técnicas Genéticas/normas , Natación , Microbiología del Agua/normas , Calidad del Agua/normas , Adaptabilidad , Monitoreo del Ambiente/economía , Técnicas Genéticas/economía
19.
PLoS One ; 9(1): e83556, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24416168

RESUMEN

Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and Agrobacterium-mediated transformation. Particle bombardment in onion epidermis was successfully established, however, it was expensive, biolistic equipment dependent and with low transformation efficiency. We developed a highly efficient in planta transient transformation method in onion epidermis by using a special agroinfiltration method, which could be fulfilled within 5 days from the pretreatment of onion bulb to the best time-point for analyzing gene expression. The transformation conditions were optimized to achieve 43.87% transformation efficiency in living onion epidermis. The developed method has advantages in cost, time-consuming, equipment dependency and transformation efficiency in contrast with those methods of particle bombardment in onion epidermal cells, protoplast transfection and Agrobacterium-mediated transient transformation in leaf epidermal cells of other plants. It will facilitate the analysis of protein subcellular localization on a large scale.


Asunto(s)
Agrobacterium/metabolismo , Técnicas Genéticas/economía , Cebollas/genética , Cebollas/microbiología , Epidermis de la Planta/microbiología , Transformación Genética , Arabidopsis/microbiología , Biolística , Epidermis de la Planta/citología , Plantas Modificadas Genéticamente , Reproducibilidad de los Resultados , Fracciones Subcelulares/metabolismo , Factores de Tiempo , Nicotiana/microbiología
20.
Vet Microbiol ; 163(3-4): 392-4, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23395292

RESUMEN

In many infection studies and approaches in breeding research it is of high importance to know the genetic predisposition of pigs for the susceptibility to the Escherichia coli (E. coli). Therefore, we developed a gene test to determine the status of the F18 receptor, as indicated by the FUT1 gene. A SNP in the FUT1 gene was first described by Vogeli et al. (1996) and a gene test was patented by Meijerink et al. (1997). Up until now, the gene test of Meijerink has been used in research. However, faster and cheaper genotyping techniques are now available, which led us to develop an easily applicable, fast and cost effective genetic test to determine the status of the F18 receptor. To check the accuracy of the new test, we genotyped 32 pigs with the established test as well as with our new test. All in all, we genotyped 430 German Landrace pigs. The test was successful. We suggest this allele specific test as a new standard genetic tool to determine the ETEC F18 receptor status in pigs.


Asunto(s)
Infecciones por Escherichia coli/genética , Fucosiltransferasas/genética , Predisposición Genética a la Enfermedad , Técnicas Genéticas/veterinaria , Enfermedades de los Porcinos/genética , Porcinos/genética , Animales , Cruzamiento , Escherichia coli Enterotoxigénica , Escherichia coli , Proteínas de Escherichia coli , Técnicas Genéticas/economía , Técnicas Genéticas/normas , Genotipo , Polimorfismo de Nucleótido Simple/genética
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