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1.
Insects ; 10(12)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817094

RESUMO

Scientifically-based, tephritid fly host status determination lies at the heart of strategic regulatory decisions impinging on international fruit trade. Here we conducted intensive field and laboratory studies with peaches as controls, to determine the host status of Physalis peruviana for the Medfly-Ceratitis capitata, as this fruit is experiencing a consumption boom worldwide. A total of 98,132 Uchuvas (local name), collected in Colombia from the plant or the ground over a three-year period (2016-2018) did not yield a single C. capitata larva or pupa, thus reaching a Probit 9 level with 99.9968% efficacy and 96% confidence level. Field-cage studies with enclosed fruit-bearing Uchuva plants, exposing fruit with an intact, damaged or totally removed husk to the attack of C. capitata, also failed to yield infestations. Highly artificial choice experiments, exposing gravid females to unripe and fully ripe fruit, resulted in an absence of infestations, even when overripe Uchuvas were artificially damaged. The husk and surface resins/waxes inhibit fly landings on fruit and oviposition activity. Considering our results and the fact that the foliage, husk and fruit of P. peruviana are repellent/toxic to insects, we conclude that this plant should be treated as a non-natural and non-conditional host of C. capitata.

2.
Med Mycol Case Rep ; 23: 31-33, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30533349

RESUMO

Chromoblastomycosis is a chronic cutaneous and subcutaneous mycosis, is caused by dematiaceous fungi, the most frequently implicated are Fonsecaea, Phialophora, Cladophialophora, Rhinocladiella and Exophiala. We report a woman who was treated before with mycological cure, but she experience a relapse requiring treatment again. Direct microscopic examination and skin biopsy with culture were necessary to identify a Exophiala psychrophila, and for our knowledge this is the first case reported.

3.
J Voice ; 31(1): 123.e1-123.e5, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26992556

RESUMO

BACKGROUND/OBJECTIVES: Spinocerebellar ataxia type 7 (SCA7) is an inherited neurodegenerative disease caused by the expansion of a cytosine-adenine-guanine triplet located in the coding region of the ATXN7 gene, which is characterized by cerebellar ataxia, pigmentary macular degeneration, and dysarthria. Although dysarthria is a common feature in various SCA, its clinical characterization has been barely approached. PATIENTS/METHODS: In this study, we report, to our knowledge for the first time, a detailed voice analysis in a large series of patients with SCA7, using different vocal parameters, including jitter, shimmer, and fundamental frequency. Patients were molecularly diagnosed using fluorescent-based polymerase chain reaction and capillary electrophoresis, and clinically characterized using the Scale for the Assessment and Rating of Ataxia and the Inventory of Non-Ataxia Symptoms. RESULTS: We found altered jitter, shimmer, and fundamental frequency measurements in patients with SCA7 compared with control subjects (P < 0.05). However, voice impairment was found unrelated with both age at disease onset and size of the cytosine-adenine-guanine triplet tract. Remarkably, jitter and shimmer measurements of patients were found to correlate with their Inventory of Non-Ataxia Symptoms, but not with their Scale for the Assessment and Rating of Ataxia scores, implying that voice impairment is the result of extra-cerebellar manifestations of the disease. CONCLUSIONS: We propose that deficiency of the extra-cerebellar component of SCA7 might lead to sudden changes in laryngeal muscle tone, producing instability in sustained vowel phonation. Clinical characterization of voice will help to discriminate SCA7 from other SCA and to guide vocal therapy treatments.


Assuntos
Ataxina-7/genética , Músculos Laríngeos/inervação , Mutação , Fonação , Acústica da Fala , Ataxias Espinocerebelares/complicações , Distúrbios da Voz/etiologia , Qualidade da Voz , Acústica , Adulto , Idoso , Estudos de Casos e Controles , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Humanos , Masculino , México , Pessoa de Meia-Idade , Fenótipo , Medida da Produção da Fala , Ataxias Espinocerebelares/diagnóstico , Ataxias Espinocerebelares/genética , Distúrbios da Voz/diagnóstico , Distúrbios da Voz/fisiopatologia
4.
Plant Cell ; 28(7): 1510-20, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27335450

RESUMO

Plant transformation has enabled fundamental insights into plant biology and revolutionized commercial agriculture. Unfortunately, for most crops, transformation and regeneration remain arduous even after more than 30 years of technological advances. Genome editing provides novel opportunities to enhance crop productivity but relies on genetic transformation and plant regeneration, which are bottlenecks in the process. Here, we review the state of plant transformation and point to innovations needed to enable genome editing in crops. Plant tissue culture methods need optimization and simplification for efficiency and minimization of time in culture. Currently, specialized facilities exist for crop transformation. Single-cell and robotic techniques should be developed for high-throughput genomic screens. Plant genes involved in developmental reprogramming, wound response, and/or homologous recombination should be used to boost the recovery of transformed plants. Engineering universal Agrobacterium tumefaciens strains and recruiting other microbes, such as Ensifer or Rhizobium, could facilitate delivery of DNA and proteins into plant cells. Synthetic biology should be employed for de novo design of transformation systems. Genome editing is a potential game-changer in crop genetics when plant transformation systems are optimized.


Assuntos
Produtos Agrícolas/genética , Edição de Genes , Genoma de Planta/genética , Agrobacterium tumefaciens/genética , Produtos Agrícolas/metabolismo , DNA de Plantas/genética , Recombinação Genética/genética , Transformação Genética/genética
5.
Mycopathologia ; 181(3-4): 165-74, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26943726

RESUMO

Fusariosis have been increasing in Colombia in recent years, but its epidemiology is poorly known. We have morphologically and molecularly characterized 89 isolates of Fusarium obtained between 2010 and 2012 in the cities of Bogotá and Medellín. Using a multi-locus sequence analysis of rDNA internal transcribed spacer, a fragment of the translation elongation factor 1-alpha (Tef-1α) and of the RNA-dependent polymerase subunit II (Rpb2) genes, we identified the phylogenetic species and circulating haplotypes. Since most of the isolates studied were from onychomycoses (nearly 90 %), we carried out an epidemiological study to determine the risk factors associated with such infections. Five phylogenetic species of the Fusarium solani species complex (FSSC), i.e., F. falciforme, F. keratoplasticum, F. lichenicola, F. petroliphilum, and FSSC 6 as well as two of the Fusarium oxysporum species complex (FOSC), i.e., FOSC 3 and FOSC 4, were identified. The most prevalent species were FOSC 3 (38.2%) followed by F. keratoplasticum (33.7%). In addition, our isolates were distributed into 23 haplotypes (14 into FOSC and nine into FSSC). Two of the FSSC phylogenetic species and two haplotypes of FSSC were not described before. Our results demonstrate that recipients of pedicure treatments have a lower probability of acquiring onychomycosis than those not receiving such treatments. The antifungal susceptibility of all the isolates to five clinically available agents showed that amphotericin B was the most active drug, while the azoles exhibited lower in vitro activity.


Assuntos
DNA Espaçador Ribossômico/genética , Dermatoses do Pé/epidemiologia , Fusariose/epidemiologia , Fusarium/classificação , Fusarium/genética , Onicomicose/epidemiologia , Fator 1 de Elongação de Peptídeos/genética , RNA Polimerase II/genética , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Colômbia/epidemiologia , Dermatoses do Pé/tratamento farmacológico , Dermatoses do Pé/microbiologia , Fusariose/tratamento farmacológico , Fusariose/microbiologia , Fusarium/efeitos dos fármacos , Fusarium/isolamento & purificação , Haplótipos/genética , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Onicomicose/tratamento farmacológico , Onicomicose/microbiologia , Filogenia , Análise de Sequência de DNA
6.
BMC Bioinformatics ; 16: 314, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26415951

RESUMO

BACKGROUND: The characterization of proteins in families and subfamilies, at different levels, entails the definition and use of class labels. When the adscription of a protein to a family is uncertain, or even wrong, this becomes an instance of what has come to be known as a label noise problem. Label noise has a potentially negative effect on any quantitative analysis of proteins that depends on label information. This study investigates class C of G protein-coupled receptors, which are cell membrane proteins of relevance both to biology in general and pharmacology in particular. Their supervised classification into different known subtypes, based on primary sequence data, is hampered by label noise. The latter may stem from a combination of expert knowledge limitations and the lack of a clear correspondence between labels that mostly reflect GPCR functionality and the different representations of the protein primary sequences. RESULTS: In this study, we describe a systematic approach, using Support Vector Machine classifiers, to the analysis of G protein-coupled receptor misclassifications. As a proof of concept, this approach is used to assist the discovery of labeling quality problems in a curated, publicly accessible database of this type of proteins. We also investigate the extent to which physico-chemical transformations of the protein sequences reflect G protein-coupled receptor subtype labeling. The candidate mislabeled cases detected with this approach are externally validated with phylogenetic trees and against further trusted sources such as the National Center for Biotechnology Information, Universal Protein Resource, European Bioinformatics Institute and Ensembl Genome Browser information repositories. CONCLUSIONS: In quantitative classification problems, class labels are often by default assumed to be correct. Label noise, though, is bound to be a pervasive problem in bioinformatics, where labels may be obtained indirectly through complex, many-step similarity modelling processes. In the case of G protein-coupled receptors, methods capable of singling out and characterizing those sequences with consistent misclassification behaviour are required to minimize this problem. A systematic, Support Vector Machine-based method has been proposed in this study for such purpose. The proposed method enables a filtering approach to the label noise problem and might become a support tool for database curators in proteomics.


Assuntos
Receptores Acoplados a Proteínas-G/classificação , Sequência de Aminoácidos , Biologia Computacional , Filogenia , Receptores Acoplados a Proteínas-G/química , Receptores Acoplados a Proteínas-G/metabolismo , Máquina de Vetores de Suporte
7.
Methods Mol Biol ; 1224: 85-96, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25416251

RESUMO

Agrobacterium-mediated transformation is the most common method for the incorporation of foreign genes into the genome of potato as well as many other species in the Solanaceae family. This chapter describes protocols for the genetic transformation of three species of potato: Solanum tuberosum subsp. tuberosum (Desiréé), S. tuberosum subsp. andigenum (Blue potato), and S. tuberosum subsp. andigena using internodal segments as explants.


Assuntos
Engenharia Genética/métodos , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/genética , Aclimatação , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/crescimento & desenvolvimento , Técnicas de Cocultura , DNA de Plantas/genética , Ambiente Controlado , Glucuronidase/genética , Plantas Geneticamente Modificadas , Solanum tuberosum/fisiologia , Transformação Genética
8.
Methods Mol Biol ; 1223: 349-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25300854

RESUMO

Agrobacterium-mediated transformation is the most common method for the incorporation of foreign genes into the genome of tomato as well as many other species in the Solanaceae family. This chapter describes a protocol for the genetic transformation of tomato cultivar Micro-Tom using cotyledons as explants. Detailed procedures are also included for determining gene-copy number using a duplex qPCR TaqMan assay, and the histochemical analysis of GUS expression.


Assuntos
Técnicas Genéticas , Lycopersicon esculentum/genética , Plantas Geneticamente Modificadas , Aclimatação , Agricultura/métodos , Agrobacterium/genética , Técnicas de Cocultura , Cotilédone/genética , Dosagem de Genes , Lycopersicon esculentum/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Sementes/genética , Transformação Bacteriana
9.
Proc Natl Acad Sci U S A ; 111(24): 8791-6, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24889615

RESUMO

Phytophthora infestans is a destructive plant pathogen best known for causing the disease that triggered the Irish potato famine and remains the most costly potato pathogen to manage worldwide. Identification of P. infestan's elusive center of origin is critical to understanding the mechanisms of repeated global emergence of this pathogen. There are two competing theories, placing the origin in either South America or in central Mexico, both of which are centers of diversity of Solanum host plants. To test these competing hypotheses, we conducted detailed phylogeographic and approximate Bayesian computation analyses, which are suitable approaches to unraveling complex demographic histories. Our analyses used microsatellite markers and sequences of four nuclear genes sampled from populations in the Andes, Mexico, and elsewhere. To infer the ancestral state, we included the closest known relatives Phytophthora phaseoli, Phytophthora mirabilis, and Phytophthora ipomoeae, as well as the interspecific hybrid Phytophthora andina. We did not find support for an Andean origin of P. infestans; rather, the sequence data suggest a Mexican origin. Our findings support the hypothesis that populations found in the Andes are descendants of the Mexican populations and reconcile previous findings of ancestral variation in the Andes. Although centers of origin are well documented as centers of evolution and diversity for numerous crop plants, the number of plant pathogens with a known geographic origin are limited. This work has important implications for our understanding of the coevolution of hosts and pathogens, as well as the harnessing of plant disease resistance to manage late blight.


Assuntos
Evolução Molecular , Phytophthora infestans/genética , Solanum tuberosum/parasitologia , Algoritmos , Teorema de Bayes , Colômbia , Equador , Genótipo , Geografia , História do Século XIX , Humanos , Irlanda , México , Repetições de Microssatélites , Dados de Sequência Molecular , Peru , Filogenia , Doenças das Plantas/história , Análise de Componente Principal , Inanição/história
10.
Med Mycol ; 51(8): 868-75, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23947747

RESUMO

Seborrheic dermatitis (SD) is a chronic, widespread skin condition, which is considered a multifactorial disease influenced, in part, by Malassezia spp. opportunistic activities, as well as various endogenous and exogenous factors. Malassezia species are lipophilic, lipid-dependent yeasts that are members of the normal mycobiota of the human skin. Their isolation from SD lesions varies around the world and the study of the relationship among factors such as gender, age, immunosuppressive condition of the patient and SD development, can lead to a better understanding of this disease. To elucidate the association of age and gender with the development of SD and to precisely determine the Malassezia species involved in the disease, samples were obtained from 134 individuals, including individuals without lesions, human immunodeficiency virus positive patients, individuals with seborrheic dermatitis, and HIV patients with seborrheic dermatitis. Malassezia spp. were identified by phenotypic and genotypic methods and a phylogenetic analysis was performed using Bayesian inference. This study revealed that age and gender are not predisposing factors for SD development, and that the most frequent species of Malassezia related to SD development among the Colombian population is M. restricta. We also report the isolation of M. yamatoensis for the first time in Colombia, and propose an ITS2 secondary structure from Malassezia taxa that can be used for precise identification and to establish more robust phylogenetic relationships.


Assuntos
Causalidade , DNA Espaçador Ribossômico/genética , Dermatite Seborreica/epidemiologia , Dermatite Seborreica/microbiologia , Malassezia/classificação , Malassezia/genética , Filogenia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Análise por Conglomerados , Colômbia/epidemiologia , DNA Espaçador Ribossômico/química , Feminino , Variação Genética , Genótipo , Infecções por HIV/complicações , Humanos , Malassezia/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Análise de Sequência de DNA , Adulto Jovem
11.
Rev. iberoam. micol ; 30(2): 81-87, abr.-jun. 2013.
Artigo em Espanhol | IBECS | ID: ibc-112578

RESUMO

Antecedentes. El tizón tardío, causado por Phytophthora infestans, es una enfermedad devastadora de la papa y el tomate a nivel mundial, y en Colombia también ataca otros cultivos como la uchuva y el tomate de árbol. El conocimiento de la población del patógeno es determinante para el diseño efectivo de estrategias de control. Objetivos. Determinar las características fisiológicas y moleculares de aislamientos colombianos de P. infestans. Métodos. El nivel de resistencia al mefenoxam y al cimoxamil fue evaluado en aislamientos de Cundinamarca y Boyacá. Se estimó su virulencia y se determinó la producción y viabilidad de oosporas en diferentes sustratos con cruces entre aislamientos A1 y el aislamiento colombiano A2. Además, se determinó la diversidad molecular en el gen de avirulencia Avr3a, el gen de la β-tubulina y otros dos genes de copia única con motivo RXLR. Resultados. Los aislamientos colombianos tuvieron la posibilidad de reproducirse sexualmente. Encontramos todos los niveles de sensibilidad al mefenoxam, con el 48% de los aislamientos resistentes. Se detectó una diversidad de razas y a nivel genético la población fue clonal. Conclusiones. Estos resultados ayudarán a optimizar el uso de fungicidas y reducir la resistencia como estrategias de control, además de contribuir al conocimiento de la diversidad de este patógeno(AU)


Background. Late blight, caused by Phytophthora infestans, is one of the most devastating diseases found in potato and tomato crops worldwide. In Colombia it also attacks other important crops: cape gooseberry and tree tomato. The knowledge of the pathogen population is determinant to effectively design control strategies. Aims. To determine the physiological and molecular characteristics of a set of Colombian P. infestans isolates. Methods. Strains isolated from Cundinamarca and Boyacá were examined for the level of resistance to mefenoxam and cymoxanil. Virulence was tested for all strains and crosses between A1 mating type, from different hosts, and the Colombian A2 mating type were tested for the production and viability of oospores in different substrates. Additionally, the molecular diversity of the avirulence gene Avr3a, the β-tubulin gene, and two single copy genes showing RxLR motif, was assessed. Results. We found all levels of mefenoxam sensitivity, with 48% of the strains resistant. A high diversity of races was detected and the population was genetically clonal. Colombian strains had the possibility of sexual reproduction. Conclusions. These results will help in optimizing the use of fungicides and deployment of resistance as control strategies and will contribute to broader studies on diversity of this pathogen(AU)


Assuntos
Phytophthora infestans/isolamento & purificação , Phytophthora infestans/patogenicidade , Virulência , Virulência/fisiologia , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/tendências , Sensibilidade e Especificidade , Phytophthora infestans , Virulência , Fatores de Virulência/isolamento & purificação , Tubulinos/isolamento & purificação , Moduladores de Tubulina , Solanum tuberosum , Solanum tuberosum Aegrotans/isolamento & purificação
12.
Rev. iberoam. micol ; 30(2): 88-95, abr.-jun. 2013.
Artigo em Espanhol | IBECS | ID: ibc-112579

RESUMO

Antecedentes. Phytophthora es el género más importante de los oomicetos, que son patógenos vegetales. Actualmente se han descrito 117 especies de este género, siendo la mayoría invasivas primarias de los tejidos vegetales. Las diferentes especies son agentes causales de enfermedades en una amplia variedad de cultivos y plantas en su medio natural. Con el objetivo de formular estrategias eficientes de control frente a especies de Phytophthora, es primordial conocer la biología, ecología y procesos evolutivos de estos importantes patógenos. Objetivos. El objetivo de este estudio fue proponer y validar un sistema de identificación de bajo coste de especies de Phytophthora con una serie de marcadores microsatélites polimórficos (SSR). Métodos. Se obtuvo un total de 33 aislamientos de diferentes especies del género, incluidas Phytophthora infestans, Phytophthora andina, Phytophthora sojae, Phytophthora cryptogea, Phytophthora nicotianae, Phytophthora capsici y Phytophthora cinnamomi. Como marcadores potencialmente transferibles entre estas especies del género Phytophthora se seleccionaron 13 microsatélites, y las condiciones de amplificación, incluidas las temperaturas de alineamiento, se estandarizaron para varios marcadores. Resultados. Un subgrupo de estos marcadores microsatélites se amplificó en todas las especies mostrando alelos específicos de especie. Conclusiones. Se describen la adaptabilidad e influencia del sistema de identificación en un país agrícola andino como Colombia, donde coexisten diferentes especies de Phytophthora en el mismo huésped o en diversos huéspedes cultivados al mismo tiempo(AU)


Background. Phytophthora is the most important genus of the Oomycete plant pathogens. Nowadays, there are 117 described species in this genus, most of them being primary invaders of plant tissues. The different species are causal agents of diseases in a wide range of crops and plants in natural environments. In order to develop control strategies against Phytophthoraspecies, it is important to know the biology, ecology and evolutionary processes of these important pathogens. Aims. The aim of this study was to propose and validate a low cost identification system for Phytophthora species based on a set of polymorphic microsatellite (SSRs) markers. Methods. Thirty-three isolates representing Phytophthora infestans, Phytophthora andina, Phytophthora sojae, Phytophthora cryptogea, Phytophthora nicotianae, Phytophthora capsici and Phytophthora cinnamomi species were obtained, and 13 SSRs were selected as potentially transferable markers between these species. Amplification conditions, including annealing temperatures, were standardized for several markers. Results. A subset of these markers amplified in all species, showing species-specific alleles. Conclusions. The adaptability and impact of the identification system in Colombia, an Andean agricultural country where different Phytophthora species co-exist in the same or in several hosts grown together, are discussed(AU)


Assuntos
Phytophthora/classificação , Phytophthora/isolamento & purificação , Phytophthora infestans/classificação , Phytophthora infestans/isolamento & purificação , Phytophthora infestans/microbiologia , Oomicetos , Oomicetos/isolamento & purificação , Biomarcadores/metabolismo , Phytophthora/microbiologia , Instabilidade de Microssatélites , Repetições de Microssatélites , Oomicetos/microbiologia , Oomicetos/patogenicidade
13.
Rev Iberoam Micol ; 30(2): 81-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23036748

RESUMO

BACKGROUND: Late blight, caused by Phytophthora infestans, is one of the most devastating diseases found in potato and tomato crops worldwide. In Colombia it also attacks other important crops: cape gooseberry and tree tomato. The knowledge of the pathogen population is determinant to effectively design control strategies. AIMS: To determine the physiological and molecular characteristics of a set of Colombian P. infestans isolates. METHODS: Strains isolated from Cundinamarca and Boyacá were examined for the level of resistance to mefenoxam and cymoxanil. Virulence was tested for all strains and crosses between A1 mating type, from different hosts, and the Colombian A2 mating type were tested for the production and viability of oospores in different substrates. Additionally, the molecular diversity of the avirulence gene Avr3a, the ß-tubulin gene, and two single copy genes showing RxLR motif, was assessed. RESULTS: We found all levels of mefenoxam sensitivity, with 48% of the strains resistant. A high diversity of races was detected and the population was genetically clonal. Colombian strains had the possibility of sexual reproduction. CONCLUSIONS: These results will help in optimizing the use of fungicides and deployment of resistance as control strategies and will contribute to broader studies on diversity of this pathogen.


Assuntos
Anti-Infecciosos/farmacologia , Phytophthora infestans , Acetamidas/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Colômbia , Sequência Conservada , Cruzamentos Genéticos , Resistência a Medicamentos , Variação Genética , Haplótipos/genética , Repetições de Microssatélites , Dados de Sequência Molecular , Phytophthora infestans/efeitos dos fármacos , Phytophthora infestans/genética , Phytophthora infestans/isolamento & purificação , Phytophthora infestans/patogenicidade , Homologia de Sequência de Aminoácidos , Solanum tuberosum/parasitologia , Especificidade da Espécie , Tubulina (Proteína)/genética , Virulência , Fatores de Virulência/genética
14.
Rev Iberoam Micol ; 30(2): 88-95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23202806

RESUMO

BACKGROUND: Phytophthora is the most important genus of the Oomycete plant pathogens. Nowadays, there are 117 described species in this genus, most of them being primary invaders of plant tissues. The different species are causal agents of diseases in a wide range of crops and plants in natural environments. In order to develop control strategies against Phytophthoraspecies, it is important to know the biology, ecology and evolutionary processes of these important pathogens. AIMS: The aim of this study was to propose and validate a low cost identification system for Phytophthora species based on a set of polymorphic microsatellite (SSRs) markers. METHODS: Thirty-three isolates representing Phytophthora infestans, Phytophthora andina, Phytophthora sojae, Phytophthora cryptogea, Phytophthora nicotianae, Phytophthora capsici and Phytophthora cinnamomi species were obtained, and 13 SSRs were selected as potentially transferable markers between these species. Amplification conditions, including annealing temperatures, were standardized for several markers. RESULTS: A subset of these markers amplified in all species, showing species-specific alleles. CONCLUSIONS: The adaptability and impact of the identification system in Colombia, an Andean agricultural country where different Phytophthora species co-exist in the same or in several hosts grown together, are discussed.


Assuntos
DNA/genética , Repetições de Microssatélites , Phytophthora/classificação , Alelos , Colômbia , Genótipo , Filogenia , Phytophthora/genética , Polimorfismo Genético , Alinhamento de Sequência , Especificidade da Espécie
15.
Salud UNINORTE ; 28(2): 238-258, jul.-dic. 2012. tab
Artigo em Espanhol | LILACS-Express | ID: lil-663816

RESUMO

Objetivo: Determinar la prevalencia y caracterizar la población en condición de discapacidad del municipio de Los Santos (Santander, Colombia), durante 2010 y 2011. Materiales y métodos: Se realizó un estudio descriptivo aplicando el instrumento de registro "Encuesta a Personas con Discapacidad y su cuidador". Estudiantes de último año de fisioterapia y bacteriología de la Universidad de Santander (UDES), previamente entrenados, recogieron la información mediante entrevista. Se realizó un análisis estadístico descriptivo aplicando medidas de tendencia central y frecuencias absolutas y relativas. Resultados: Se encontraron 108 PCD, la prevalencia de discapacidad de esta población fue de 1,3% (IC 95% 1,1-1,6), la vereda con mayor prevalencia fue Los Teres (9,4%; IC95% 5,1-15,5). De las 108 PCD, el 48% corresponde a género femenino y el 47,2°% se encuentra entre 15 y 44 años. La estructura corporal con mayor deficiencia fue el sistema nervioso, con un 64,8%, y las actividades de demanda general fueron las más afectadas (57,4%). Los problemas con servicios, sistemas y políticas de transporte, seguro social, salud y educación constituyen el principal facilitador (57, 4%). Conclusión: La discapacidad como problema de salud pública afecta las actividades, participación y desempeño de las PCD, lo cual disminuye su desarrollo individual y sus oportunidades de integración a la sociedad.


Objective: To determine the prevalence and characterize the condition of disabled people in the municipality Los Santos, Santander in 2010 and 2011. Materials and methods: A descriptive study was conducted using the tool of record "Survey of Persons with Disabilities and its attendant". Physiotherapy and bacteriology students from University of Santander (UDES), previously trained, collected the information by interview. We use descriptive statistics applying central tendency measures and absolute and relative frequencies. Results: We found 108 people with disabilities; the prevalence of disability in this popu-lation was 1.3% (95% CI 1.1 -1.6), the place with the highest prevalence was Los Teres (9.4%; 95% CI 5.1-15.5). Of the 108 disabled people, 48% were female and 47.2% were between 15 and 44 years old. The body structure more impairment was nervous system with a 64.8% and general tasks and demands were the most affected (57.4%). Problems with services, transport systems and policies, social security, health, and education were the main facilitator (57.4%). Conclusion: Disability as a public health problem affecting the activities, participation and performance of the people with disabilities decreasing their individual development and opportunities for integration into society.

16.
Laryngoscope ; 122(11): 2557-62, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22991211

RESUMO

OBJECTIVES/HYPOTHESIS: To characterize the progression of hearing loss in patients with immune-mediated inner ear disease (IMIED), and to identify disease- and patient-specific factors associated with cochlear implant (CI) performance. STUDY DESIGN: Retrospective cohort study. METHODS: Subjects consisted of CI patients suspected to have lost their hearing due to IMIED. The primary dependent variable for functional decline was time to deafness, whereas for CI benefit it was post-CI speech perception scores. Independent variables included presence or absence of systemic autoimmune disease, age at CI, and insertion depth of the cochlear electrode. RESULTS: A transient favorable response to immunosuppressive therapy was reported in 16 of 26 patients (66.67%). The time to deafness differed between an organ (ear)-specific immune-mediated group, a systemic immune-mediated group including Cogan syndrome and relapsing polychondritis (subgroup A), and a systemic immune-mediated group associated with other autoimmune diseases (subgroup B; P = .001). Disease group (-15.52; P = .04), insertion depth of the CI electrode (40.71; P = .01), and the age at CI (-0.48, P = .05) were associated with speech perception results. CONCLUSIONS: Triaging IMIED cases based on presence and type of systemic autoimmune disease may aid in selecting a management strategy. Knowledge about the predictors of CI outcome will help clinicians select appropriate patients for CIs. In the setting of significant and irreversible hearing deficit, the restoration of hearing using a cochlear prosthesis may be appropriate earlier rather than later.


Assuntos
Doenças Autoimunes/complicações , Implantes Cocleares , Surdez/imunologia , Surdez/reabilitação , Adulto , Idoso , Idoso de 80 Anos ou mais , Interpretação Estatística de Dados , Progressão da Doença , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Percepção da Fala , Resultado do Tratamento
17.
PLoS One ; 7(9): e44832, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22970314

RESUMO

In the Neotropics, almost every species of the stream-dwelling harlequin toads (genus Atelopus) have experienced catastrophic declines. The persistence of lowland species of Atelopus could be explained by the lower growth rate of Batrachochytrium dendrobatidis (Bd) at temperatures above 25 °C. We tested the complementary hypothesis that the toads' skin bacterial microbiota acts as a protective barrier against the pathogen, perhaps delaying or impeding the symptomatic phase of chytridiomycosis. We isolated 148 cultivable bacterial strains from three lowland Atelopus species and quantified the anti-Bd activity through antagonism assays. Twenty-six percent (38 strains representing 12 species) of the bacteria inhibited Bd growth and just two of them were shared among the toad species sampled in different localities. Interestingly, the strongest anti-Bd activity was measured in bacteria isolated from A. elegans, the only species that tested positive for the pathogen. The cutaneous bacterial microbiota is thus likely a fitness-enhancing trait that may (adaptation) or not (exaptation) have appeared because of natural selection mediated by chytridiomycosis. Our findings reveal bacterial strains for development of local probiotic treatments against chytridiomycosis and also shed light on the mechanisms behind the frog-bacteria-pathogen interaction.


Assuntos
Fenômenos Fisiológicos Bacterianos , Bufonidae/microbiologia , Quitridiomicetos/patogenicidade , Micoses/fisiopatologia , Animais , Sequência de Bases , Bufonidae/classificação , Quitridiomicetos/crescimento & desenvolvimento , Primers do DNA , Micoses/microbiologia , Reação em Cadeia da Polimerase , Especificidade da Espécie
18.
Acta biol. colomb ; 17(2): 227-240, mayo-ago. 2012. ilus, graf, tab
Artigo em Inglês | LILACS-Express | ID: lil-659302

RESUMO

Phytophthora infestans, the causal agent of late blight disease in potato and other members of the Solanaceae family, is responsible for causing the Irish potato famine and, even today, it causes enormous economic losses all over the world. For the establishment of an adequate pest management strategy, the determination of the pathogen's population structure is required. To characterize P. infestans populations worldwide two allozymes, Gpi (Glucose-6-phospate isomerase) and Pep ( Pep tidase), the RG57 DNA RFLP fingerprinting probe, as well as resistance to the fungicide metalaxyl and mating type, have been used as markers. P. infestans populations in Mexico have been one of the main focuses of research in the population biology of this pathogen because this country has been considered as one of the possible centers of origin of this oomycete. In this review we present the population structure of P. infestans in Mexico, Europe, Africa, Asia, North America, and South America, expanding it on the present situation of P. infestans in Colombia. Finally, we will discuss different lines of research that are being carried out today with respect to P. infestans in Colombia, which have shown the importance of continuing the study of this devastating plant pathogen in our country.


Phytophthora infestans, el agente causal del tizón tardío de la papa y otros miembros de la familia de las Solanáceas, es el responsable de la gran hambruna irlandesa y aún hoy sigue causando grandes pérdidas económicas alrededor del planeta. Para establecer estrategias de control adecuadas contra este patógeno se requiere comprender la estructura poblacional del mismo. Mundialmente se han utilizado como marcadores las aloenzimas, Gpi (Glucosa-6-fosfato isomerasa) y Pep (Peptidasa) y la sonda de fingerprinting de RFLP (Polimorfismos de la Longitud de los Fragmentos de Restricción), RG57. De igual forma, la resistencia al fungicida metalaxyl y el tipo de apareamiento, han sido empleados para caracterizar las poblaciones de P. infestans. Las poblaciones de P. infestans en México han sido uno de los focos principales de investigación en la biología poblacional de este patógeno debido a que este país ha sido considerado como uno de los posibles centros de origen de este oomiceto. En esta revisión se presentará la estructura poblacional de P. infestans en México, Europa, África, Asia, Norte América y Sur América, profundizando en la situación actual de P. infestans en Colombia. Finalmente, se discutirá las diferentes líneas de investigación que se llevan a cabo hoy respecto a P. infestans en Colombia, las cuales han mostrado la importancia de continuar con el estudio de este devastador patógeno de plantas en nuestro país.

19.
J Microbiol ; 50(6): 1009-13, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23274988

RESUMO

Endophytes are microorganisms that asymptomatically invade plant tissues. They can stimulate plant growth and/or provide defense against pathogen attacks through the production of secondary metabolites. Most endophyte species are still unknown, and because they may have several applications, the study of their metabolic capabilities is essential. We characterized 100 endophytes isolated from Espeletia spp., a genus unique to the paramo ecosystem, an extreme environment in the Andean mountain range. We evaluated the cellulolytic potential of these endophytes on the saccharification of the oil palm empty fruit bunch (OPEFB). The total cellulolytic activity was measured for each endophyte on filter paper (FPA). In addition, the specific carboxymethyl cellulase (CMCase), exoglucanase, and ß-glucosidase activities were determined. We found four fungi positive for cellulases. Of these fungi, Penicillium glabrum had the highest cellulolytic activity after partial purification, with maximal CMCase, exoglucanase and ß-glucosidase enzyme activities of 44.5, 48.3, and 0.45 U/ml, respectively. Our data showed that the bioprospection of fungi and the characterization of their enzymes may facilitate the process of biofuel production.


Assuntos
Celulases/metabolismo , Endófitos/enzimologia , Gleiquênias/microbiologia , Fungos/enzimologia , Celulases/isolamento & purificação , Ativação Enzimática , Fungos/isolamento & purificação
20.
Rev. iberoam. micol ; 28(4): 166-172, oct.-dic. 2011.
Artigo em Espanhol | IBECS | ID: ibc-91058

RESUMO

resumen(AU)


Background. Fusarium oxysporum has worldwide distribution and causes severe vascular wilt or root rot in many plants. Strains are classified into formae speciales based on their high degree of host specificity, of which multilocus sequence typing provides a fairly good estimate. Aims. The main aim of this study was to identify the causal agent of an infected potato tuber in Colombia. Methods. Two F. oxysporum isolates were recovered from a potato tuber showing symptoms of dry rot. Both macroscopic and microscopic morphology differences were observed between the two isolates. Koch's postulates were verified and in quantitative tuber pathogenecity trials, both isolates induced moderate dry rot. Ribosomal internal transcribed spacer (ITS) and partial intergenic spacer region (IGS) sequences were PCR-amplified, sequenced and shown to be identical for the two isolates. A maximum parsimony phylogeny was created using F. oxysporum IGS sequences available in the Genebank database, which does not include sequences from the formae speciales tuberosi. Results. Our two isolates were most closely related to a red clover (Trifolium pratense) pathogenic isolate and two non-pathogenic F. oxysporum isolates from birdsfoot trefoil (Lotus corniculatus) and Lycopersicon sp. rhyzosphere (99% identity). Conclusions. These experiments showed that our isolates are not restricted to potato and that a molecular marker is needed to differentiate the formae speciales since the IGS and EF-1alpha do not have the power to do it(AU)


Assuntos
Fusarium/isolamento & purificação , Solanum tuberosum/classificação , Solanum tuberosum/virologia , Filogenia , DNA Espaçador Ribossômico/análise , DNA Espaçador Ribossômico/isolamento & purificação , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Fusarium/patogenicidade , Microscopia/métodos , Microscopia , Virulência , Virulência/fisiologia , Fatores de Virulência/isolamento & purificação
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