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1.
Fungal Genet Biol ; 174: 103924, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39094785

RESUMEN

Fusarium head blight (FHB) is a major disease of wheat and barley worldwide and is caused by different species in the genus Fusarium, Fusarium graminearum being the most important. We conducted population genomics analyses using SNPs obtained through genotyping by sequencing of over 500 isolates of F. graminearum from the US Upper Midwest, New York, Louisiana, and Uruguay. PCA and STRUCTURE analyses group our isolates into four previously described populations: NA1, NA2, Southern Louisiana (SLA) and Gulf Coast (GC). Some isolates were not assigned to populations because of mixed ancestry. Population structure was associated with toxin genotype and geographic origin. The NA1, NA2, and SLA populations are differentiated (FST 0.385 - 0.551) but the presence of admixed isolates indicates that the populations are not reproductively isolated. Patterns of linkage disequilibrium (LD) decay suggest frequent recombination within populations. Fusarium graminearum populations from the US have great evolutionary potential given the high recombination rate and a large proportion of admixed isolates. The NA1, NA2, and Southern Louisiana (SLA) populations separated from their common ancestral population roughly at the same time in the past and are evolving with moderate levels of subsequent gene flow between them. Genome-wide selection scans in all three populations revealed outlier regions with the strongest signatures of recent positive natural selection. These outlier regions include many genes with unknown function and some genes with known roles in plant-microbe interaction, fungicide/drug resistance, cellular transport and genes that are related to cellular organelles. Only a very small proportion of outlier regions are shared as outliers among the three populations, suggesting unique host-pathogen interactions and environmental adaptation.

2.
J Sci Food Agric ; 104(2): 561-571, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37607216

RESUMEN

Postharvest management is critical to attaining household food, nutrition, and income security. Hermetic grain storage bags offer an effective pesticide-free way to protect stored grain against fungal and insect infestation. We evaluated articles indexed in the Web of Science that included experiments comparing the storage efficacy of conventional and hermetic storage bags based on grain germination rate, insect infestation, physical damage, mycotoxin contamination, and changes in weight and moisture content. Compared with grain stored in hermetic bags, grain stored in conventional bags lost 3.6-fold more seed viability, contained 42-fold more insects, had 11-fold more physical damage, and lost 23-fold more grain weight, while grain moisture levels were similar for both hermetic and conventional storage bags. Mycotoxin contamination levels were not as frequently assessed. Levels could be low in grain stored in both types of bags, or levels could be low in hermetic bags and significantly higher in conventional bags. The improved properties of grain stored in hermetic bags can increase food security and household income by providing safe storage options for maintaining seed germinability, and for consumption and/or sale when food supplies are high, or when prices are low. Hermetic bags are economically feasible for use by subsistence farmers in Sub-Saharan Africa for grain for household consumption and for carrying-over seed for planting in the next season. Additional studies are needed to verify the mycotoxin contamination results and to determine if there are differences in functional food characteristics, e.g. flavor and cooking properties, that have not been as comprehensively studied. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Agricultores , Micotoxinas , Animales , Humanos , Grano Comestible/química , Semillas/química , Insectos , Micotoxinas/análisis
3.
Toxins (Basel) ; 15(9)2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37755985

RESUMEN

Foodborne mycotoxins are a significant food safety risk in developing countries. Our objective was to determine the occurrence of and exposure levels to aflatoxins (AFs) and fumonisins (FBs) in maize intended for human and animal consumption in food-insecure regions of western Honduras. Total AFs and FBs were quantified with a monoclonal antibody-based affinity spectrofluorimetric method. FBs were detected in 614/631 samples of maize destined for human consumption at 0.3 to 41 mg/kg (mean, 2.7 mg/kg). Of the 614 positive samples, 147 had FB levels exceeding the U.S. Food and Drug Administration (FDA) advisory threshold of 4.0 mg/kg. AFs were detected in 109/631 samples of maize for human consumption with concentrations between 1.0 and 490 µg/kg (mean, 10 µg/kg). AF levels in 34 samples exceeded the FDA regulatory limit (i.e., 20 µg/kg). The average probable daily intake of AFs in western Honduras ranged from 0 to 260 ng/kg body weight/day, and for FBs, the average probable daily intake ranged from 17 to 53 µg/kg body weight/day. AFs and FBs co-occurred in 106/631 samples with 60 samples containing both toxins at levels greater than the FDA regulatory levels. Samples of maize intended for animal feed had significantly higher AF (mean, 22 µg/kg) and FB (mean, 7.6 mg/kg) contamination levels than those observed in samples destined for human consumption. Thus, the maize supply chain in western Honduras is contaminated with mycotoxins at levels that pose health risks to both humans and livestock. More effective mycotoxin surveillance and implementation of effective mitigation strategies are needed to reduce mycotoxin contamination and exposure.


Asunto(s)
Aflatoxinas , Fumonisinas , Micotoxinas , Estados Unidos , Animales , Humanos , Zea mays , Honduras , Peso Corporal
5.
Compr Rev Food Sci Food Saf ; 21(4): 3227-3243, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35638328

RESUMEN

Nearly 700,000 tonnes of peanuts are consumed annually in Europe. In the last 5 years, peanuts imported from China exceeded legal European Union (EU) aflatoxin limits more than 180 times. To prevent and mitigate aflatoxin contamination, the stages of the peanut chain most vulnerable to contamination must be assessed to determine how to interrupt the movement of contaminated produce. This paper discusses effective approaches for early identification and proactive mitigation of aflatoxins in peanuts to reduce a contaminant that is an impediment to trade. We consider (i) the results of the EU Commission's Directorate-General (DG) for Health and Food Safety review, (ii) the Code of Practice for the prevention and reduction of aflatoxins in peanuts issued by Food and Agriculture Organization/World Health Organization, (iii) the results from previous EU-China efforts, and (iv) the latest state-of-the-art technology in pre- and postharvest methods as essential elements of a sustainable program for integrated disease and aflatoxin management. These include preharvest use of biocontrol, biofertilizers, improved tillage, forecasting, and risk monitoring based on analysis of big data obtained by remote sensing. At the postharvest level, we consider rapid testing methods along the supply chain, Decision Support Systems for effective silo management, and effective risk monitoring during drying, storage, and transport. Available guidance and current recommendations are provided for successful practical implementation. Food safety standards also influence stakeholder and consumer trust and confidence, so we also consider the results of multiactor stakeholder group discussions.


Asunto(s)
Aflatoxinas , Arachis , Unión Europea , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Inocuidad de los Alimentos
6.
Fungal Biol ; 126(3): 250-266, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35183341

RESUMEN

Many species in the Fusarium fujikuroi Species Complex (FFSC) have an affinity for grass species, with whom they live in an endophytic association or cause disease. We recovered isolates of Fusarium from agriculturally important grasses in Africa and Brazil, and characterized them with morphological markers, mating type, and Amplified Fragment Length Polymorphisms (AFLPs). We also conducted multi-locus phylogenetic analyses based on partial DNA sequences of translation elongation factor-1α (TEF1), ß-tubulin (TUB), and the second largest subunit of RNA polymerase (RPB2) gene regions. Sexual cross fertility was used to test the biological species concept and the sexual stage of F. madaense is described. A novel species within the FFSC, Fusarium mirum, that is different from the other known species in the complex, was formally described. Fusarium mirum, F. madaense, and Fusarium andiyazi are a tightly intertwined species trio that are morphologically identical, but phylogenetically distinguishable, and amongst whom interspecific genetic exchange may still occur. These three species are so close that they cannot be reliably distinguished if only sequences of the TEF1 gene are used. In pathogenicity tests, all tested isolates of F. madaense from sugarcane, sorghum, maize, millet and Brachiaria could induce stalk rot in sorghum, maize and millet, and pokkah boeng in sugarcane. This study increases our understanding of the diversity of species within the FFSC that cause disease in tropical grasses or act as endophytes, and their geographic distributions. The genetically close relationship between F. mirum, F. madaense, and F. andiyazi provides an opportunity to study and identify factors underlying their limited inter-specific cross-fertility and sympatric speciation.


Asunto(s)
Fusarium , Fusarium/genética , Filogenia , Poaceae , Zea mays
7.
J Cataract Refract Surg ; 48(3): 355-362, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34415863

RESUMEN

PURPOSE: To compare the repair of penetrating corneal incisions in an in vivo rabbit model using a laser-activated thin-film adhesive, sutures, or self-seal. SETTING: The University of Sydney, Camperdown, Australia. DESIGN: Animal studies. METHODS: Under an operating microscope, 2.0 mm penetrating incisions were created in 162 right eyes. Incisions in one group were repaired with the adhesive, the second group received a single 10-0 nylon suture, and the third group was left to self-seal. Rabbits were killed humanely at predetermined timepoints over 2 weeks, and wound healing was assessed using burst pressure and immunohistological studies. A modified McDonald-Shadduck scoring was used to assess eyes. RESULTS: The mean burst pressure of the adhesive group was significantly higher than the sutured or self-sealed groups at all timepoints within the first 72 hours. At 0 hour, the burst pressure was 98.0 (±17.0) mm Hg, 30.6 (±2.1) mm Hg, and 3.8 (±0.6) mm Hg (P < .00001) for adhesive-treated (n = 5), sutured (n = 5), and self-sealed wounds (n = 5), respectively. These increased to 229.0 (±53.7) mm Hg, 12.4 (±2.9) mm Hg, and 27.3 (±4.0) mm Hg (P = .0011) at 72 hours. The modified McDonald-Shadduck score was significantly higher for eyes repaired using the adhesive than those sutured or left to self-seal for the first 72 hours. On histology and immunofluorescence, adhesive treatment demonstrated better wound approximation and higher myofibroblastic activation than the other groups. CONCLUSIONS: The adhesive was efficacious in sealing penetrating corneal incisions and tolerated higher burst pressures than sutures or self-seal. The adhesive was biocompatible in rabbits, and incisions demonstrated a rapid gain in wound strength that sustained over the study period.


Asunto(s)
Adhesivos Tisulares , Adhesivos , Animales , Córnea/patología , Córnea/cirugía , Rayos Láser , Conejos , Adhesivos Tisulares/uso terapéutico , Cicatrización de Heridas
8.
Toxins (Basel) ; 13(10)2021 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-34679018

RESUMEN

Mycotoxins in small grains are a significant and long-standing problem. These contaminants may be produced by members of several fungal genera, including Alternaria, Aspergillus, Fusarium, Claviceps, and Penicillium. Interventions that limit contamination can be made both pre-harvest and post-harvest. Many problems and strategies to control them and the toxins they produce are similar regardless of the location at which they are employed, while others are more common in some areas than in others. Increased knowledge of host-plant resistance, better agronomic methods, improved fungicide management, and better storage strategies all have application on a global basis. We summarize the major pre- and post-harvest control strategies currently in use. In the area of pre-harvest, these include resistant host lines, fungicides and their application guided by epidemiological models, and multiple cultural practices. In the area of post-harvest, drying, storage, cleaning and sorting, and some end-product processes were the most important at the global level. We also employed the Nominal Group discussion technique to identify and prioritize potential steps forward and to reduce problems associated with human and animal consumption of these grains. Identifying existing and potentially novel mechanisms to effectively manage mycotoxin problems in these grains is essential to ensure the safety of humans and domesticated animals that consume these grains.


Asunto(s)
Grano Comestible/microbiología , Contaminación de Alimentos/prevención & control , Micotoxinas , Triticum/microbiología , Producción de Cultivos/métodos , Manipulación de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Fungicidas Industriales , Enfermedades de las Plantas/microbiología
9.
Transl Vis Sci Technol ; 10(8): 27, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34319386

RESUMEN

Purpose: The purpose of this study was to investigate whether laser irradiation, used to activate an adhesive for sealing penetrating corneal incisions, causes any ophthalmoscopically or histologically visible retinal changes. Methods: Baseline fundus assessment was conducted prior to laser irradiation of eyes of pigmented Dutch Belted rabbits. Treatment group was 18 eyes with the corneal adhesive activated in situ by a near infrared laser (125 mW for 45 seconds). The positive control group was 18 eyes, each irradiated for 60 seconds at 375, 500, 625, and 750 mW at different retinal locations. Unexposed regions of the retina were used as negative internal control. Ophthalmoscopic assessment was conducted immediately after laser exposure and prior to euthanasia. Retinas were histologically assessed at 0, 3, 72, and 168 hours after treatment. Results: No ophthalmoscopically or histologically visible retinal changes were observed in the treatment group immediately, nor up to 168 hours after laser irradiation. In the positive control group, the incidences of ophthalmoscopically visible retinal lesions increased with irradiation power: 5.6% at 375 mW, 16.7% at 500 mW, 44.4% at 625 mW, and 50% at 750 mW. Histologically, retinal damage was observed as coagulative necrosis to all layers of the neural retina, including the retinal pigment epithelium. Conclusions: The laser irradiation process used in the corneal adhesive technology did not cause any ophthalmoscopically or histologically visible retinal changes in the in vivo pigmented rabbit model. Prolonged exposure with this laser and at higher power can cause coagulative necrosis to the retina. Translational Relevance: The corneal adhesive can be applied in humans without causing laser retinal damage.


Asunto(s)
Adhesivos , Coagulación con Láser , Animales , Rayos Láser , Oftalmoscopía , Conejos , Retina
10.
Phytopathology ; 111(1): 170-183, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33079019

RESUMEN

Fusarium subglutinans and F. temperatum are two important fungal pathogens of maize whose distinctness as separate species has been difficult to assess. We isolated strains of these species from commercial and native maize varieties in Argentina and sequenced >28,000 loci to estimate genetic variation in the sample. Our objectives were to measure genetic divergence between the species, infer demographic parameters related to their split, and describe the population structure of the sample. When analyzed together, over 30% of each species' polymorphic sites (>2,500 sites) segregate as polymorphisms in the other. Demographic modeling confirmed the species split predated maize domestication, but subsequent between-species gene flow has occurred, with gene flow from F. subglutinans into F. temperatum greater than gene flow in the reverse direction. In F. subglutinans, little evidence exists for substructure or recent selective sweeps, but there is evidence for limited sexual reproduction. In F. temperatum, there is clear evidence for population substructure and signals of abundant recent selective sweeps, with sexual reproduction probably less common than in F. subglutinans. Both genetic variation and the relative number of polymorphisms shared between species increase near the telomeres of all 12 chromosomes, where genes related to plant-pathogen interactions often are located. Our results suggest that species boundaries between closely related Fusarium species can be semipermeable and merit further study. Such semipermeability could facilitate unanticipated genetic exchange between species and enable quicker permanent responses to changes in the agro-ecosystem, e.g., pathogen-resistant host varieties, new chemical and biological control agents, and agronomic practices.


Asunto(s)
Fusarium , Argentina , Ecosistema , Fusarium/genética , Flujo Génico , Enfermedades de las Plantas , Zea mays
11.
Toxins (Basel) ; 12(11)2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-33187262

RESUMEN

Affordable and practical tools for farmers and food processors along the chain are required to efficiently reduce the risk of mycotoxin contamination of crops, feeds and foods. Developing new tools and enhancing existing ones was the mission of MyToolBox-a four-year EU-project that included important Chinese partners and joint research efforts. To identify future directions in mycotoxin research and management in China and their role in China-EU relations, a unique stakeholder workshop including group discussions was organized in Beijing. Six related topics: biocontrol, forecasting, sampling and analysis, silo management, detoxification, and the development of safe use options for contaminated materials were covered. The discussions clearly identified a critical need for smart, integrated strategies to address mycotoxin issues to attain safer food and feed, and to minimize losses and export rejections. Managing data on when, where and the size of mycotoxin contamination events and identifying the institution(s) to manage them are complex issues in China. Studies of microbes and novel, genetically-altered enzymes to limit pre-harvest contamination and to manage post-harvest product detoxification and alternate uses of contaminated materials are in the early stages in China. Further efforts are needed to increase the visibility of mycotoxin problems beyond the scientific and research communities.


Asunto(s)
Contaminación de Alimentos/prevención & control , Cooperación Internacional , Micotoxinas , Agricultura/métodos , Agentes de Control Biológico , China , Unión Europea , Contaminación de Alimentos/análisis , Predicción , Micotoxinas/análisis , Investigación
12.
mSphere ; 5(5)2020 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-32938701

RESUMEN

This article is to alert medical mycologists and infectious disease specialists of recent name changes of medically important species of the filamentous mold FusariumFusarium species can cause localized and life-threating infections in humans. Of the 70 Fusarium species that have been reported to cause infections, close to one-third are members of the Fusarium solani species complex (FSSC), and they collectively account for approximately two-thirds of all reported Fusarium infections. Many of these species were recently given scientific names for the first time by a research group in the Netherlands, but they were misplaced in the genus Neocosmospora In this paper, we present genetic arguments that strongly support inclusion of the FSSC in Fusarium There are potentially serious consequences associated with using the name Neocosmospora for Fusarium species because clinicians need to be aware that fusaria are broadly resistant to the spectrum of antifungals that are currently available.


Asunto(s)
Fusarium/clasificación , Filogenia , Antifúngicos/farmacología , Fusarium/efectos de los fármacos
13.
Appl Environ Microbiol ; 86(13)2020 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-32358011

RESUMEN

Fusarium subglutinans and Fusarium temperatum are common maize pathogens that produce mycotoxins and cause plant disease. The ability of these species to produce beauvericin and fumonisin mycotoxins is not settled, as reports of toxin production are not concordant. Our objective was to clarify this situation by determining both the chemotypes and genotypes for strains from both species. We analyzed 25 strains from Argentina, 13 F. subglutinans and 12 F. temperatum strains, for toxin production by ultraperformance liquid chromatography mass spectrometry (UPLC-MS). We used new genome sequences from two strains of F. subglutinans and one strain of F. temperatum, plus genomes of other Fusarium species, to determine the presence of functional gene clusters for the synthesis of these toxins. None of the strains examined from either species produced fumonisins. These strains also lack Fum biosynthetic genes but retain homologs of some genes that flank the Fum cluster in Fusarium verticillioides None of the F. subglutinans strains we examined produced beauvericin although 9 of 12 F. temperatum strains did. A complete beauvericin (Bea) gene cluster was present in all three new genome sequences. The Bea1 gene was presumably functional in F. temperatum but was not functional in F. subglutinans due to a large insertion and multiple mutations that resulted in premature stop codons. The accumulation of only a few mutations expected to disrupt Bea1 suggests that the process of its inactivation is relatively recent. Thus, none of the strains of F. subglutinans or F. temperatum we examined produce fumonisins, and the strains of F. subglutinans examined also cannot produce beauvericin. Variation in the ability of strains of F. temperatum to produce beauvericin requires further study and could reflect the recent shared ancestry of these two species.IMPORTANCEFusarium subglutinans and F. temperatum are sister species and maize pathogens commonly isolated worldwide that can produce several mycotoxins and cause seedling disease, stalk rot, and ear rot. The ability of these species to produce beauvericin and fumonisin mycotoxins is not settled, as reports of toxin production are not concordant at the species level. Our results are consistent with previous reports that strains of F. subglutinans produce neither fumonisins nor beauvericin. The status of toxin production by F. temperatum needs further work. Our strains of F. temperatum did not produce fumonisins, while some strains produced beauvericin and others did not. These results enable more accurate risk assessments of potential mycotoxin contamination if strains of these species are present. The nature of the genetic inactivation of BEA1 is consistent with its relatively recent occurrence and the close phylogenetic relationship of the two sister species.


Asunto(s)
Depsipéptidos/análisis , Fumonisinas/análisis , Fusarium/química , Fusarium/genética , Genotipo , Análisis de Secuencia de ADN , Especificidad de la Especie
14.
Curr Eye Res ; 45(9): 1025-1030, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32460646

RESUMEN

AIM: To review the use of clinical corneal sealants for the closure of full thickness corneal wounds. METHODS: A systematic review was conducted across CENTRAL, Medline, PubMed, Embase, Scopus, mRCT and ICTRP for the keywords of 'cornea', 'full-thickness wound', 'sealant' and their synonyms. Only evidence level 2 of higher as graded by Oxford Centre of Evidence-based Medicine were included for this review. RESULTS: Seven studies were included; three randomized controlled trials investigated ReSure® sealant, 2 OcuSeal®, 1 human fibrin glue vs cyanoacrylate and 1 human fibrin glue as an adjunct to sutures vs sutures alone in penetrating keratoplasty. ReSure® was superior to suture for sealing leaking corneal incisions after cataract surgery despite provocation. ReSure® sealant has not been tested on complex full thickness corneal wounds, perforated ulcers or penetrating keratoplasty. OcuSeal® was also able to seal full thickness cornea wound post-cataract surgery to prevent ingress of Trypan blue dye. Human fibrin glue and cyanoacrylate were similarly effective in treating corneal perforations <3 mm of mixed etiologies. CONCLUSION: There are limited high-level evidence for corneal sealants. The currently available sealants with human data are ReSure®, OcuSeal®, human fibrin glue and cyanoacrylates. While ReSure® and OcuSeal® are effective post-cataract surgery, there are no data for perforations from other etiologies. Post-approval data from ReSure® registry report good tolerability and no apparent safety concerns.


Asunto(s)
Lesiones de la Cornea/tratamiento farmacológico , Adhesivos Tisulares/uso terapéutico , Cianoacrilatos/uso terapéutico , Adhesivo de Tejido de Fibrina/uso terapéutico , Humanos
15.
Sci Rep ; 9(1): 19836, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31882627

RESUMEN

Fusarium proliferatum causes diverse diseases of many economically important plants. The fungus produces several mycotoxins of which the fumonisins are the most toxic. Currently, deletion of key genes for mycotoxin biosynthesis is a laborious and time-consuming procedure. We developed a novel CRISPR/Cas9-based genome-editing tool for the direct delivery of preassembled Cas9 ribonucleoproteins into protoplasts of F. proliferatum. Our CRISPR-Cas9 system couples a site-specific double-strand DNA break mediated by two Cas9 ribonucleoproteins with microhomology recombination requiring only 50-bp regions flanking the target gene. This system reduces the risk of off-target mutations and minimizes the risk of altering any gene adjacent to the target region. We used this tool to delete a polyketide synthase gene (FUM1) required for fumonisin biosynthesis. The mutants generated are no longer able to produce fumonisins, confirming the key role of FUM1 in fumonisin biosynthesis. Our CRISPR-Cas9 system is an important new tool for genetic studies of Fusarium.


Asunto(s)
Sistemas CRISPR-Cas , Fumonisinas/metabolismo , Fusarium/genética , Edición Génica/métodos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fusarium/metabolismo , Eliminación de Gen , Mutación , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Reproducibilidad de los Resultados
16.
Plant Pathol J ; 35(4): 301-312, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31481853

RESUMEN

Sorghum is the fifth most important cereal worldwide, spreading from Africa throughout the world. It is particularly important in the semi-arid tropics due to its drought tolerance, and when cultivated in Southeast Asia commonly occurs as a second crop during the dry season. We recovered Fusarium from sorghum in Thailand and found F. proliferatum, F. thapsinum and F. verticillioides most frequently, and intermittent isolates of F. sacchari and F. beomiforme. The relatively high frequencies of F. proliferatum and F. verticillioides, suggest mycotoxin contamination, particularly fumonisins and moniliformin, should be evaluated. Genetic variation within the three commonly recovered species was characterized with vegetative compatibility, mating type, Amplified Fragment Length Polymorphisms (AFLPs), and female fertility. Effective population number (N e ) was highest for F. verticillioides and lowest for F. thapsinum with values based on mating type allele frequencies higher than those based on female fertility. Based on AFLP genetic variation, the F. thapsinum populations were the most closely related, the F. verticillioides populations were the most distantly related, and the F. proliferatum populations were in an intermediate position. The genetic variation observed could result if F. thapsinum is introduced primarily with seed, while F. proliferatum and F. verticillioides could arrive with seed or be carried over from previous crops, e.g., rice or maize, which sorghum is following. Confirmation of species transmission patterns is needed to understand the agricultural systems in which sorghum is grown in Southeast Asia, which are quite different from the systems found in Africa, Australia, India and the Americas.

17.
Int J Food Microbiol ; 296: 31-36, 2019 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-30826540

RESUMEN

Maize (Zea mays), sorghum (Sorghum bicolor) and pearl millet (Pennisetum glaucum) are basic staple foods for many rural or poorer communities. These crops are susceptible to plant diseases caused by multiple species of Fusarium, some of which also produce mycotoxins, including fumonisins and moniliformin that are detrimental to both humans and domesticated animals. Eighteen potentially toxigenic Fusarium strains were isolated from maize (n = 10), sorghum (n = 7) and pearl millet (n = 1) growing in the same field in Nigeria. The 17 strains from maize and sorghum were all F. proliferatum and the one strain from pearl millet was F. pseudonygamai. Under conducive conditions, the 17 F. proliferatum strains produced fumonisins, 11 in relatively large quantities (700-17,000 mg total fumonisins, i.e., FB1 + FB2 + FB3/kg culture material), and six at <45 mg/kg. Ten F. proliferatum strains produced >100 mg of moniliformin per kg culture material with a maximum of 8900 mg/kg culture material. All strains could use all grains for growth and toxin production, regardless of the host from which they were isolated. Isolates varied in the amount of toxin produced on each substrate, with toxin production a property of the strain and not the host from which the strain was recovered. However, the extent to which a toxin-producing phenotype could be altered by the grain on which the fungus was grown is consistent with subtle genetic × environment interactions that require a larger data set than the one presented here to rigorously identify. In conclusion, there is significant variation in the ability of strains of F. proliferatum to produce fumonisins and moniliformin on maize, sorghum and millet. If the amount of toxin produced on the various grains in this study reflects real-world settings, e.g., poor storage, then the consumers of these contaminated grains could be exposed to mycotoxin levels that greatly exceed the tolerable daily intakes.


Asunto(s)
Ciclobutanos/análisis , Fumonisinas/análisis , Fusarium/patogenicidad , Micotoxinas/análisis , Pennisetum/microbiología , Sorghum/microbiología , Zea mays/microbiología , Animales , Grano Comestible/microbiología , Fusarium/aislamiento & purificación , Nigeria , Enfermedades de las Plantas/microbiología
18.
Toxins (Basel) ; 10(4)2018 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-29617309

RESUMEN

Mycotoxins are major food contaminants affecting global food security, especially in low and middle-income countries. The European Union (EU) funded project, MycoKey, focuses on “Integrated and innovative key actions for mycotoxin management in the food and feed chains” and the right to safe food through mycotoxin management strategies and regulation, which are fundamental to minimizing the unequal access to safe and sufficient food worldwide. As part of the MycoKey project, a Mycotoxin Charter (charter.mycokey.eu) was launched to share the need for global harmonization of mycotoxin legislation and policies and to minimize human and animal exposure worldwide, with particular attention to less developed countries that lack effective legislation. This document is in response to a demand that has built through previous European Framework Projects—MycoGlobe and MycoRed—in the previous decade to control and reduce mycotoxin contamination worldwide. All suppliers, participants and beneficiaries of the food supply chain, for example, farmers, consumers, stakeholders, researchers, members of civil society and government and so forth, are invited to sign this charter and to support this initiative.


Asunto(s)
Exposición a Riesgos Ambientales/prevención & control , Contaminación de Alimentos/prevención & control , Cooperación Internacional , Micotoxinas , Salud Global , Humanos
19.
Toxins (Basel) ; 10(3)2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29494529

RESUMEN

MycoKey, an EU-funded Horizon 2020 project, includes a series of "Roundtable Discussions" to gather information on trending research areas in the field of mycotoxicology. This paper includes summaries of the Roundtable Discussions on Chemical Detection and Monitoring of mycotoxins and on the role of genetics and biodiversity in mycotoxin production. Discussions were managed by using the nominal group discussion technique, which generates numerous ideas and provides a ranking for those identified as the most important. Four questions were posed for each research area, as well as two questions that were common to both discussions. Test kits, usually antibody based, were one major focus of the discussions at the Chemical Detection and Monitoring roundtable because of their many favorable features, e.g., cost, speed and ease of use. The second area of focus for this roundtable was multi-mycotoxin detection protocols and the challenges still to be met to enable these protocols to become methods of choice for regulated mycotoxins. For the genetic and biodiversity group, both the depth and the breadth of trending research areas were notable. For some areas, e.g., microbiome studies, the suggested research questions were primarily of a descriptive nature. In other areas, multiple experimental approaches, e.g., transcriptomics, proteomics, RNAi and gene deletions, are needed to understand the regulation of toxin production and mechanisms underlying successful biological controls. Answers to the research questions will provide starting points for developing acceptable prevention and remediation processes. Forging a partnership between scientists and appropriately-placed communications experts was recognized by both groups as an essential step to communicating risks, while retaining overall confidence in the safety of the food supply and the integrity of the food production chain.


Asunto(s)
Micotoxinas , Animales , Biodiversidad , Monitoreo del Ambiente , Humanos , Micotoxinas/análisis , Micotoxinas/genética , Investigación
20.
Respir Med Case Rep ; 22: 271-273, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29062682

RESUMEN

Transudative chylothorax is a rare type of pleural effusion. It has been described to be present in the setting of liver cirrhosis, heart failure, amyloidosis, nephrotic syndrome, superior vena cava thrombosis, sclerosing mesenteritis and heart failure. We present the case of an 86-year-old woman with a right-side transudative chylothorax associated with heart failure and lymphangioleiomyomatosis.

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