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1.
Rev Alerg Mex ; 71(1): 75, 2024 Feb 01.
Artigo em Espanhol | MEDLINE | ID: mdl-38683092

RESUMO

OBJECTIVE: To evaluate the risk of IgE sensitization and symptoms to shrimp in a population that has received AIT with polymerized mite extract. METHODS: Patients with allergic rhinitis sensitized to dust mites (Dermatophogides spp) with an indication for mite AIT were included. Those patients who had not yet received AIT or had received less than 6 doses were included as controls and those who had received more than 24 doses of AIT were included as cases. Sensitization to shrimp was assessed by skin prick test with complete shrimp extract and/or shrimp-specific IgE. RESULTS: A total of 68 patients were included; 47 cases and 21 controls. When calculating the odds ratio of sensitization according to time with immunotherapy we observed that there were no differences between the group of cases and controls (OR 0.76 95% CI 0.26 to 2.22 p 0.7 by MacNemar technique). Factors such as consumption or not of shrimp and frequency of consumption do not seem to be related to the outcome. CONCLUSION: In contrast to what was reported with aqueous extracts, we observed that AIT with polymerized extracts is not a risk factor for shrimp sensitization. It is necessary to reproduce these results with a larger sample size to explore other factors.


OBJETIVO: Evaluar el riesgo de sensibilización IgE y síntomas a camarón en una población que ha recibido AIT con extracto polimerizado para ácaros. MÉTODOS: Se incluyeron pacientes con rinitis alérgica sensibilizados a ácaros del polvo (Dermatophogides spp) con indicación de AIT para ácaros. Aquellos pacientes que no habían aún recibido AIT o llevaban menos de seis dosis, fueron incluidos como controles, y aquellos que llevaban más de 24 dosis de AIT, fueron incluidos como casos. Se evaluó la sensibilización a camarón mediante prueba cutánea con extracto completo de camarón y/o IgE específica a camarón. RESULTADOS: En total, 68 pacientes fueron incluidos; 47 casos y 21 controles. Al calcular el odds ratio de la sensibilización de acuerdo al tiempo con la inmunoterapia, observamos que no había diferencias entre el grupo de casos y controles (OR 0,76 95% IC 0,26 a 2,22 p 0,7 por técnica de MacNemar). Factores como el consumo o no de camarón y la frecuencia de consumo, no parecen estar relacionados con el desenlace. CONCLUSIÓN: A diferencia de lo reportado con extractos acuosos, observamos de AIT con extractos polimerizados para no es un factor de riesgo para la sensibilización a camarón. Es necesario reproducir estos resultados con un mayor tamaño de muestra que permita explorar otros factores.


Assuntos
Dessensibilização Imunológica , Penaeidae , Pyroglyphidae , Humanos , Animais , Masculino , Feminino , Pyroglyphidae/imunologia , Adulto , Penaeidae/imunologia , Adolescente , Adulto Jovem , Criança , Pessoa de Meia-Idade , Polimerização , Rinite Alérgica/terapia , Antígenos de Dermatophagoides/imunologia , Imunoglobulina E/imunologia
2.
Phytopathology ; 113(1): 90-97, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36095335

RESUMO

The global banana industry is threatened by one of the most devastating diseases: Fusarium wilt of banana. Fusarium wilt of banana is caused by the soilborne fungus Fusarium oxysporum f. sp. cubense (Foc), which almost annihilated the banana production in the late 1950s. A new strain of Foc, known as tropical race 4 (TR4), attacks a wide range of banana varieties, including Cavendish clones, which are the source of 99% of banana exports. In 2019, Foc TR4 was reported in Colombia, and more recently (2021) in Peru. In this study, we sequenced three fungal isolates identified as Foc TR4 from La Guajira (Colombia) and compared them against 19 whole-genome sequences of Foc TR4 publicly available, including four genome sequences recently released from Peru. To understand the genetic relatedness of the Colombian Foc TR4 isolates and those from Peru, we conducted a phylogenetic analysis based on a genome-wide set of single nucleotide polymorphisms (SNPs). Additionally, we compared the genomes of the 22 available Foc TR4 isolates, looking for the presence-absence of gene polymorphisms and genomic regions. Our results reveal that (i) the Colombian and Peruvian isolates are genetically distant, which could be better explained by independent incursions of the pathogen to the continent, and (ii) there is a high correspondence between the genetic relatedness and geographic origin of Foc TR4. The profile of present/absent genes and the distribution of missing genomic regions showed a high correspondence to the clades recovered in the phylogenetic analysis, supporting the results obtained by SNP-based phylogeny.


Assuntos
Fusarium , Musa , Fusarium/genética , Filogenia , Doenças das Plantas/microbiologia , Sequência de Bases , América do Sul , Musa/microbiologia
3.
Microbiol Resour Announc ; 11(1): e0098021, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34989603

RESUMO

We report a draft genome assembly of the causal agent of tomato vascular wilt, Fusarium oxysporum f. sp. lycopersici isolate 59, obtained from the Andean region in Colombia.

4.
J Fungi (Basel) ; 7(4)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33920770

RESUMO

Banana, the main export fruit for Colombia, is threatened by Fusarium wilt (FWB), caused by Fusarium oxysporum f. sp. cubense (Foc), tropical race 4 (TR4). Pathogen containment through disinfecting tools, machinery, shoes, and any means that may carry contaminated soil particles with proper disinfectants is at the forefront of disease management. In this study, the biocide efficacy of 10 commercial quaternary ammonium compounds (QACs) products and one based on glutaraldehyde (GA) were evaluated on both reproductive structures (microconidia and macroconidia) and survival spores (chlamydospores) of Foc TR4 (strain 140038) isolated from La Guajira, Colombia. QACs were evaluated at 1200 ppm and two exposure times: <1 and 15 min in the absence or presence of soil. For GA disinfectant, four different concentrations (500, 800, 1200, and 2000 ppm) were evaluated at both contact times in the presence of soil. In the absence of soil, all QACs showed 100% biocidal efficiency against microconidia, macroconidia, and chlamydospores at both <1 and 15 min. The presence of soil decreased the efficacy of disinfectants, but some of them, such as QAC3_1st, QAC7_4th, and QAC5_4th, showed 98%, 98%, and 100% efficacy against Foc TR4 chlamydospores, respectively, after <1 min of contact time. For instance, the GA-based disinfectant was able to eliminate all Foc TR4 propagules after 15 min for all concentrations tested.

5.
Sci Rep ; 11(1): 520, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436847

RESUMO

The plant growth-promoting bacterium Azospirillum brasilense contains several genes encoding proteins involved in the biosynthesis and degradation of the second messenger cyclic-di-GMP, which may control key bacterial functions, such as biofilm formation and motility. Here, we analysed the function and expression of the cdgD gene, encoding a multidomain protein that includes GGDEF-EAL domains and CHASE and PAS domains. An insertional cdgD gene mutant was constructed, and analysis of biofilm and extracellular polymeric substance production, as well as the motility phenotype indicated that cdgD encoded a functional diguanylate protein. These results were correlated with a reduced overall cellular concentration of cyclic-di-GMP in the mutant over 48 h compared with that observed in the wild-type strain, which was recovered in the complemented strain. In addition, cdgD gene expression was measured in cells growing under planktonic or biofilm conditions, and differential expression was observed when KNO3 or NH4Cl was added to the minimal medium as a nitrogen source. The transcriptional fusion of the cdgD promoter with the gene encoding the autofluorescent mCherry protein indicated that the cdgD gene was expressed both under abiotic conditions and in association with wheat roots. Reduced colonization of wheat roots was observed for the mutant compared with the wild-type strain grown in the same soil conditions. The Azospirillum-plant association begins with the motility of the bacterium towards the plant rhizosphere followed by the adsorption and adherence of these bacteria to plant roots. Therefore, it is important to study the genes that contribute to this initial interaction of the bacterium with its host plant.


Assuntos
Azospirillum brasilense/genética , GMP Cíclico/genética , GMP Cíclico/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Expressão Gênica , Interações entre Hospedeiro e Microrganismos/genética , Domínios Proteicos/genética , Azospirillum brasilense/fisiologia , Aderência Bacteriana , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Mutação , Raízes de Plantas/microbiologia , Sistemas do Segundo Mensageiro , Triticum/microbiologia
6.
FEMS Microbiol Lett ; 367(4)2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32105306

RESUMO

Elucidation of biofilm structure formation in the plant growth-promoting rhizobacterium Azospirillum brasilense is necessary to gain a better understanding of the growth of cells within the extracellular matrix and its role in the colonization of plants of agronomic importance. We used immunofluorescence microscopy and confocal laser scanning microscopy to study spatio-temporal biofilm formation on an abiotic surface. Observations facilitated by fluorescence microscopy revealed the presence of polar flagellin, exopolysaccharides, outer major membrane protein (OmaA) and extracellular DNA in the Azospirillum biofilm matrix. In static culture conditions, the polar flagellum disaggregated after 3 days of biofilm growth, but exopolysaccharides were increasing. These findings suggest that the first step in biofilm formation may be attachment, in which the bacterium first makes contact with a surface through its polar flagellum. After attaching to the surface, the long flagella and OmaA intertwine the cells to form a network. These bacterial aggregates initiate biofilm development. The underlying mechanisms dictating how the biofilm matrix components of A. brasilense direct the overall morphology of the biofilm are not well known. The methods developed here might be useful in further studies that analyze the differential spatial regulation of genes encoding matrix components that drive biofilm construction.


Assuntos
Azospirillum brasilense/fisiologia , Biofilmes/crescimento & desenvolvimento , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Azospirillum brasilense/crescimento & desenvolvimento , Proteínas da Membrana Bacteriana Externa/metabolismo , DNA Bacteriano/metabolismo , Flagelina/metabolismo , Cinética , Microscopia Confocal , Microscopia de Fluorescência , Polissacarídeos Bacterianos/metabolismo
7.
Pathogens ; 9(1)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968574

RESUMO

In Colombia, tomato production under protected conditions represents an important economic contribution to the agricultural sector. Fusarium wilt diseases, caused by pathogenic formae speciales of the soil-borne fungus Fusarium oxysporum Schltdl., cause significant yield losses in tomatoes throughout the world. Investigation of the F. oxysporum-tomato pathosystem in Colombia is required to develop appropriate alternative disease management. In this study, 120 fungal isolates were obtained from four different departments in the Central Andean Region in Colombia from tomato crops with symptoms of wilt disease. A molecular characterization of the fungal isolates was performed using the SIX1, SIX3, and SIX4 effector genes of Fusarium oxysporum f. sp. lycopersici W.C. Snyder & H.N. Hansen (Fol). Additionally, we developed a new specific marker to distinguish between Fusarium oxysporum f. sp. radicis-lycopersici Jarvis & Shoemaker (Forl) and Fol isolates. Furthermore, a phylogenetic analysis using the Translation Elongation Factor 1-alpha (EF1a) gene was performed with the collected isolates. Two isolates (named Fol59 and Fol-UDC10) were identified as Fol race 2, four isolates were identified as Forl, six isolates were identified as F. solani, and most of the isolates were grouped within the F. oxysporum species complex. The phylogenetic tree of EF1a showed that most of the isolates could potentially correspond to nonpathogenic strains of F. oxysporum. Additional pathogenicity assays carried out with Fol59 and Fol-UDC10 confirmed that both isolates were highly virulent strains. This study represents a contribution to the understanding of the local interaction between tomatoes and F. oxysporum in Colombia.

8.
Acta toxicol. argent ; 24(1): 2-9, jul. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-837849

RESUMO

Las mezclas químicas o la presencia conjunta de signos y síntomas de intoxicación crónica son dos de los principales desafíos para el estudio toxicológico y epidemiológico de la exposición a plaguicidas. En este estudio fue explorada la aplicabilidad del análisis cualitativo comparativo con conjuntos nítidos (csQCA) para superar estas difcultades. Los datos de síntomas y signos clínicos de intoxicación de 43 trabajadores del cultivo de arroz en Guamo y Espinal (Tolima, Colombia) fueron recolectados, y se midió la presencia de heptacloro en sangre total con cromatografía de gases con detector de captura de electrones. Se realizaron tablas de verdad con las principales confguraciones (presencia conjunta de signos y síntomas), y se evaluó su consistencia y cobertura. En 90,70 % de los trabajadores se detectó heptacloro. Cuarenta y nueve signos y síntomas fueron reportados, siendo los más frecuentes las alteraciones del sueño, el mareo y la visión borrosa. Cinco confguraciones resultaron asociadas con la detección de heptacloro en sangre (cobertura: 0,872 y consistencia: 0,971), aunque sólo tres resultan útiles para la práctica clínica. Este procedimiento permitió diseñar un listado de tamizaje para detección de individuos con exposición a heptacloro. La experiencia mostró uno de los potenciales uso de csQCA en toxicología. Futuros estudios podrán explorar mejor el valor predictivo de estos hallazgos en diversas poblaciones.


Chemical mixtures or the conjoint presence of signs and symptoms of chronic poisoning are two of the main challenges to the toxicologic and epidemiologic study of exposure to pesticides. In this study was explored the applicability of crispsets qualitative comparative analysis (csQCA) to overcome these diffculties. Data on symptoms and signs of poisoning from 43 agricultural workers living in Guamo or Espinal (Cundinamarca, Colombia) were collected, and the presence of heptachlor was measured in total blood with gas chromatography with electron capture detector. Truth tables with main confgurations were performed, and consistence and coverage were estimated. Heptachlor was detected among 90.70% of workers. Forty-nine symptoms and signs were reported, being the most frequent sleep disorders, dizziness and blurred vision. Five confgurations were associated with the detection of heptachlor in blood (coverage: 0.872 and consistence: 0.971), although only three are useful for clinical practice. This procedure allowed the design of a list of screening for detection of individuals with exposure to heptachlor. This experience showed one of the potential uses of csQCA in toxicology. Future studies may further explore the predictive value of these fndings in different populations.


Assuntos
Humanos , Sinais e Sintomas , Estudos de Avaliação como Assunto/métodos , Exposição a Praguicidas , Heptacloro/intoxicação , Heptacloro/sangue , Trabalhadores Rurais , Zona Rural , Análise Multivariada , Colômbia/epidemiologia
9.
Arch Environ Occup Health ; 71(1): 3-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24972111

RESUMO

This study describes the use of pesticides mixtures and their potential association with comet assay results in 223 rice field workers in Colombia. Thirty-one pesticides were quantified in blood, serum, and urine (15 organochlorines, 10 organophosphorus, 5 carbamates, and ethylenethiourea), and the comet assay was performed. Twenty-four (77.42%) pesticides were present in the workers. The use of the maximum-likelihood factor analysis identified 8 different mixtures. Afterwards, robust regressions were used to explore associations between the factors identified and the comet assay. Two groups of mixtures--α-benzene hexachloride (α-BHC), hexachlorobenzene (HCB), and ß-BHC (ß: 1.21, 95% confidence interval [CI]: 0.33-2.10) and pirimiphos-methyl, malathion, bromophos-methyl, and bromophos-ethyl (ß: 11.97, 95% CI: 2.34-21.60)--were associated with a higher percentage of DNA damage and comet tail length, respectively. The findings suggest that exposure to pesticides varies greatly among rice field workers.


Assuntos
Agricultura , Dano ao DNA/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Oryza , Praguicidas/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carbamatos/efeitos adversos , Carbamatos/análise , Colômbia , Ensaio Cometa , Estudos Transversais , Etilenotioureia/efeitos adversos , Etilenotioureia/análise , Feminino , Humanos , Hidrocarbonetos Clorados/efeitos adversos , Hidrocarbonetos Clorados/análise , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Compostos Organofosforados/efeitos adversos , Compostos Organofosforados/análise , Praguicidas/sangue , Adulto Jovem
10.
J Biol Chem ; 289(22): 15554-65, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24737323

RESUMO

Estrogen receptor α (ERα) mediates the effects of 17ß-estradiol (E2) in normal mammary gland, and it is a key participant in breast cancer tumor development. ERα transactivation activity is mediated by the synergistic interaction of two domains designated AF1 and AF2. The function of AF2 is to recruit coactivator and corepressor proteins that allow ERα to oscillate between the roles of transcriptional activator and repressor. In contrast, the mechanism responsible for AF-1 transcriptional activity is not completely understood. In this study, we identified tristetraproline (TTP) as a novel ERα-associated protein. TTP expression in MCF7 cells repressed ERα transactivation and reduced MCF7 cell proliferation and the ability of the cells to form tumors in a mouse model. We show that TTP transcriptional activity is mediated through its recruitment to the promoter region of ERα target genes and its interaction with histone deacetylases, in particular with HDAC1. TTP expression attenuates the coactivating activity of SRC-1, suggesting that exchange between TTP and other coactivators may play an important role in fine-tuning ERα transactivation. These results indicate that TTP acts as a bona fide ERα corepressor and suggest that this protein may be a contributing factor in the development of E2-dependent tumors in breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/metabolismo , Tristetraprolina/metabolismo , Animais , Neoplasias da Mama/genética , Proliferação de Células , Proteínas Correpressoras/metabolismo , Estradiol/metabolismo , Estradiol/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Histona Desacetilases/metabolismo , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Transplante de Neoplasias , Transcrição Gênica/fisiologia
11.
Med. U.P.B ; 31(1): 34-41, ene.-jun. 2012.
Artigo em Espanhol | LILACS, COLNAL | ID: lil-638467

RESUMO

Actualmente las enfermedades autoinmunes tienen una alta prevalencia. Éstas son enfermedades que, por su sintomatología, pueden generar alteraciones del estado de ánimo en quienes las padecen. La depresión es uno de los trastornos más comunes y, por ello, la necesidad de reconocer la frecuencia con que se presenta el trastorno depresivo en pacientes con estas enfermedades y sus repercusiones.


Autoimmune diseases are highly prevalent today. These are diseases that sometimes, for their symptoms, can cause mood disturbances in the patient, with depression being one the most common disorders. Hence the importance of recognizing the frequency of depressive disorder occurring in patients with these diseases and the impact this simultaneous presentation can have on the individual


Assuntos
Humanos , Doenças Autoimunes , Transtorno Depressivo , Saúde Mental , Depressão
12.
Mol Genet Metab ; 103(3): 240-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21463962

RESUMO

This work examines the cellular localization of holocarboxylase synthetase (HCS) and its association to chromatin during different stages of development of Drosophila melanogaster. While HCS is well known for its role in the attachment of biotin to biotin-dependent carboxylase, it also regulates the transcription of HCS and carboxylases genes by triggering a cGMP-dependent signal transduction cascade. Further, its presence in the nucleus of cells suggests additional regulatory roles, but the mechanism involved has remained elusive. In this study, we show in D. melanogaster that HCS migrates to the nucleus at the gastrulation stage. In polytene chromosomes, it is associated to heterochromatin bands where it co-localizes with histone 3 trimethylated at lysine 9 (H3K9met3) but not with the euchromatin mark histone 3 acetylated at lysine 9 (H3K9ac). Further, we demonstrate the association of HCS with the hsp70 promoter by immunofluorescence and chromatin immuno-precipitation (ChIP) of associated DNA sequences. We demonstrate the occupancy of HCS to the core promoter region of the transcriptionally inactive hsp70 gene. On heat-shock activation of the hsp70 promoter, HCS is displaced and the promoter region becomes enriched with the TFIIH subunits XPD and XPB and elongating RNA pol II, the latter also demonstrated using ChIP assays. We suggest that HCS may have a role in the repression of gene expression through a mechanism involving its trafficking to the nucleus and interaction with heterochromatic sites coincident with H3K9met3.


Assuntos
Carbono-Nitrogênio Ligases/metabolismo , Cromatina/metabolismo , Drosophila melanogaster/embriologia , Drosophila melanogaster/enzimologia , Sequência de Aminoácidos , Animais , Anticorpos/metabolismo , Carbono-Nitrogênio Ligases/genética , Núcleo Celular/enzimologia , Drosophila melanogaster/genética , Proteínas de Choque Térmico HSP72/genética , Células Hep G2 , Histonas/metabolismo , Temperatura Alta , Humanos , Dados de Sequência Molecular , Cromossomos Politênicos/genética , Cromossomos Politênicos/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Transporte Proteico , Alinhamento de Sequência
13.
Perspect. nutr. hum ; (15): 67-82, ene.-jun. 2006.
Artigo em Espanhol | LILACS | ID: lil-489211

RESUMO

El envejecimiento es un proceso dinámico, progresivo e irreversible en el que intervienen múltiples factores biológicos, psíquicos y sociales; una alta proporción de la sociedad ve en el envejecimiento, un proceso en el que las personas pierden su autonomía, independencia, la capacidad laboral e intelectual; convirtiéndose el adulto mayor en una carga para sus familias y la sociedad. En los últimos años este concepto está cambiando favorablemente, en parte por el deseo de las personas adultas y de los adultos mayores de tener un envejecimiento exitoso o activo como lo define la Organización Mundial de la Salud (OMS), en el cual convergen las oportunidades de bienestar físico, social y mental que se han tenido durante toda la vida, y la aceptación del envejecimiento como una etapa más del proceso vital en la que debe tenerse una adecuada nutrición y actividad física, aspectos que general-mente son descuidados en esta etapa. El proceso de envejecimiento lo enfrentan todos los países del mundo, algunos con índices más elevados; aunque Colombia no presenta tales índices, se deben establecer estrategias que redunden en una buena calidad de vida de los adultos mayores.


The aging is a dynamic, progressive and irreversible process influenced bymany biological, physical and social factors. High proportion of the societysees in aging, a process in which people lose their autonomy, independence,and intellectual capacity, consequently elderly people become a burden fortheir families and for the society. During last years, this concept has beenchanging favorably in part because of desire of adults and elderly people ofhaving a successful and active aging as defined by the Word Health organization.This definition consist of physical, social and mental well-being opportunitiesof elderly stage as part of the vital process, with adequate nutritionand physical activity, aspects, that are usually neglected. This process is experienced by all countries in the world, some of them with higher rates. Although Colombia does not have those rates, strategies need be established inorder to improve the quality of life of this population.


Assuntos
Humanos , Idoso , Envelhecimento , Nível de Saúde , Ciências da Nutrição
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