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Improved Reference Genome Sequence of Coccidioides immitis Strain WA_211, Isolated in Washington State.
Coccidioides fungi are widely distributed in the American continents, with an expanding western range documented by a recently discovered cryptic population of Coccidioides immitis in Washington State. The assembled and annotated reference genome sequence of the soil-derived C. immitis strain WA_211 will support population and functional genomics studies
Especiação, genômica comparativa e reprodução sexuada no complexo de espécies do gênero Paracoccidioides
Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Biologia Celular, 2012.A Paracoccidioidomicose (PCM) é uma micose sistêmica que ocorre em vários países da América Latina, principalmente Brasil, Venezuela e Colômbia, afetando principalmente indivíduos da população rural. Por meio de estudos realizados nos campos da Biologia Molecular, Biologia Evolutiva e Ecologia no gênero Paracoccidioides, foi proposto neste trabalho uma nova espécie: Paracoccidioides lutzii sp. nov. Análises filogenéticas, estudos de genômica comparativa, análises de recombinação genética e análises morfológicas demonstram que P. lutzii representa uma linhagem altamente divergente monofileticamente separada de P. brasiliensis. P. lutzii é frequentemente encontrado nas regiões Centro-Oeste e Norte do Brasil. Os estudos comparativos entre os genomas de P. brasiliensis e P. lutzii revelaram uma alta divergência e diferenças significativas no tamanho do genoma, conteúdo gênico, elementos transponíveis, e repetições simples foram identificadas entre estas espécies. Estudos comparativos entre as espécies divergentes P. brasiliensis e P. lutzii geraram informações que podem ser utilizadas na clínica bem como no diagnóstico da PCM. Estudos de filogenia molecular indicaram que estas duas espécies de Paracoccidioides teriam um ciclo de vida sexuado devido à detecção de eventos de recombinação genética dentro destas populações. Estudos de genômica comparativa de todos os fungos dimórficos e patogênicos, usando como base os dados já classicamente descritos para a levedura Saccharomyces cerevisiae, revelaram a presença de genes relacionados à reprodução sexuada que incluem: o locus MAT e genes de receptores de feromônios, de feromônio-α, de enzimas de processamento de feromônios e reguladores de sinalização de resposta a feromônios. A expressão destes genes foi avaliada por PCR em tempo real em isolados de Paracoccidioides nas formas de micélio e levedura, demostrando-se ter uma expressão preferencial na forma filamentosa, similar ao que já foi descrito para Histoplasma capsulatum e Blastomyces dermatitidis. Além disto, a expressão dos genes relacionados ao ciclo sexual teve um aumento significativo quando na presença de feromônios obtidos de sobrenadantes de co-cultura de isolados de tipos sexuais opostos. Cruzamentos de diferentes tipos sexuais, tanto de P. brasiliensis como de P. lutzii, possibilitaram a identificação de ascocarpos jovens com presença de hifas enoveladas e constritas, relacionadas ao estágio inicial do acasalamento em fungos “Pezizomycotina”. Estes dados genômicos e morfológicos fortemente indicam a existência de ciclo sexual no gênero Paracoccidioides. _________________________________________________________________________________ ABSTRACTParacoccidioidomycosis (PCM) is a systemic mycosis that occurs in several Latin American countries, mainly Brazil, Venezuela and Colombia, affecting mostly the rural population. Through studies in the fields of Molecular Biology, Evolutionary Biology and Ecology in the genus Paracoccidioides, it was proposed in this work a new species: Paracoccidioides lutzii sp. nov. Phylogenetic analyzes, comparative genomics, analysis of genetic recombination and morphological analysis showed that P. lutzii represents a separate species, highly divergent from P. brasiliensis. P. lutzii is often found in the midwest and north part of Brazil. Comparative genomics studies between P. brasiliensis and P. lutzii revealed a high divergence and differences in genome size, gene content, transposable elements and DNA repeats were identified between these species. Comparative studies between the diverging species P. brasiliensis and P. lutzii generated information that can be useful in the clinical diagnosis of PCM. Evolutionary studies suggested that these two species of Paracoccidioides have a sexual phase in its life cycle due detection of recombination events within these populations. Studies of comparative genomics of all dimorphic fungal pathogens, using classically described genes for the yeast Saccharomyces cerevisiae, revealed the presence of genes related to sexual reproduction that include: the MAT locus, pheromone receptors and genes encoding for α-pheromone, processing enzymes and regulatory pheromone response to pheromone signaling cascade. The expression of these genes has been evaluated by real time PCR of Paracoccidioides isolates in yeast and mycelial forms, showing an increased expression in the filamentous form, similar to what was already described for Histoplasma capsulatum and Blastomyces dermatitidis. Moreover, the expression of genes related to sexual cycle increased significantly after exposure of pheromone taken from co-culture supernatants of strains of opposite sex type. Sexual crosses between different mating types, of P. brasiliensis and P. lutzii, enabled the identification of young ascocarps with hyphae reeled and constricted, related to the initial stage of mating in Pezizomycotina fungi. These genomic and morphological data strongly indicate the existence of sexual cycle in the genus Paracoccidioides
Paracoccidioides species complex : ecology, phylogeny, sexual reproduction, and virulence
Paracoccidioidomycosis (PCM) is a deep systemic mycosis caused by human fungal pathogens of the Paracoccidioides genus. The disease is geographically restricted to subtropical areas of Latin America (from south of Mexico to north of Argentina) with a high prevalence in Brazil, Colombia, Venezuela, and Argentina [1]. The annual incidence rate in Brazil is 10–30 infections per million inhabitants, and the mean mortality rate is 1.4 per million inhabitants per year, making this disease the highest cause of mortality among systemic mycoses [2]. PCM is endemic in rural populations and mainly affects individuals engaged in agricultural activities, who inhale aerosols containing fungal material during manipulation of the soil. Molecular evolutionary studies place the genus Paracoccidioides in the thermodimorphic fungal pathogen clade related to the family Ajellomycetaceae (Ascomycetes), which includes the Blastomyces,
Histoplasma, and Emmonsia genera, and with which it shares a common ancestor, Lacazia loboi. PCM can be caused by two species Paracoccidioides brasiliensis and P. lutzii [3]. P. brasiliensis has been considered a single species since its discovery, although several studies including molecular and morphological data support the split of P. brasiliensis into two species [3,4]. P. lutzii is composed of a single monophyletic and recombining population so far found in central, southwest, and north Brazil and Ecuador [3–5]. On the other hand, P. brasiliensis contains a complex of at least four different cryptic species (S1, PS2, PS3 and PS4; Figure 1A [6]). P. brasiliensis S1 represents a monophyletic and recombining population widely distributed in South America and has been associated with the majority of cases of PCM detected up until the present time. Strains belonging to P. brasiliensis S1 have previously been recovered from armadillos, soil, and penguin feces [6]. P. brasiliensis PS2 is a paraphyletic and recombining population identified so far only in Brazil and Venezuela [6]. P. brasiliensis PS3 is comprised of a monophyletic and clonal population that has been recovered in humans and armadillos in endemic regions of Colombia [6]. P. brasiliensis PS4 was recently identified and is composed of a monophyletic population of clinical isolates from Venezuela [5,7]. Besides the typical bicorn cocked hat– and barrel-shaped conidia produced by both species, P. lutzii frequently produces elongated rod-shaped conidia, a characteristic feature that may be used for species identification [3]. Because of the difficulties of conidia production in the laboratory and slight morphological differences among species, molecular identification of Paracoccidioides species has become the most common tool of choice. Several molecular markers have already been applied in population studies of the
Pararacoccidioides genus, and for multilocus sequencing typing, gp43, arf, b-tub, and hsp70 loci are the best choices for species delineation [4,6]
Objetos de ensino e o patrimônio cultural de ciência e tecnologia no Brasil e em Portugal: contribuições sobre levantamentos e inventários como instrumentos de preservação em escolas de ensino médio
O trabalho faz reflexões sobre o patrimônio cultural no âmbito das escolas de ensino médio, analisando algumas iniciativas de levantamentos e de valoração dos objetos de ensino enquanto bens culturais. Para tanto, buscamos traçar um perfil analítico de projetos de inventário desse patrimônio cultural no Brasil e em Portugal. A partir das lentes da ciência e tecnologia, utilizou- se a revisão bibliográfica e os contatos com as instituições como metodologia para compararo estado de pesquisas de inventário sobre estes objetos. Observou-se que as iniciativas aqui estudadas são assimétricas, necessitando ser padronizadas e aprofundadas de forma a alcançar as diferentes modalidades de ensino e, consequentemente, obter resultados mais consistentes e efetivos do ponto de vista da preservação. No entanto, percebe-se que existe um movimento crescente de identificação e preservação desses artefatos nos dois países.This study offers some reflections about cultural heritage in secondary schools, analyzing some initiatives to survey and enhance the value of teaching objects as cultural assets. An analytical profile of inventories of cultural heritage at secondary schools in Brazil and Portugal is presented. Considering the perspective of science and technology heritage, the methodology involved a literature review and direct contact with institutions to survey and compare the state of inventory-based research of such objects. The initiatives studied here were found to be asymmetrical, requiring standardization and more in-depth analysis to encompass different types of education, thus obtaining more consistent and effective results from a preservation perspective. Nonetheless, there is a growing movement to identify and preserve these artifacts in both countries
Technological characterization of cupressus spp. Wood
Os objetivos deste estudo foram determinar as características anatômicas, propriedades
mecânicas e a durabilidade natural da madeira de cipreste (Cupressus spp.) exposta ao fungo de
podridão-parda, o Gloeophyllum trabeum (Persoon ex Fries) Murrill, e ao fungo de podridãobranca,
o Trametes versicolor (Linnaeus ex Fries) Pilat. A madeira tem grã direita, cor branca
a marrom, textura média e brilho moderado. Apresenta de média a baixa densidade, baixa
contração e moderada estabilidade dimensional. O teor de lignina foi relativamente alto,
enquanto a de extrativos foi baixa. A madeira de Cupressus spp. apresentou 4,1 GPa para o
módulo de elasticidade; 91,0 MPa para o módulo de ruptura; 1,8 MPa para a ligação interna e
6357; e 4039 N para a dureza Janka de topo e lateral, respectivamente. Todas as propriedades
mecânicas, na condição seca, foram semelhantes aos descritos para ciprestes e algumas espécies
de madeira da Amazônia. A madeira de cipreste foi classificada como altamente resistente aos
fungos de podridão-parda Gloeophyllum trabeum e de podridão branca Trametes versicolor,
tornando-a adequada para uso interior e exterior e meio ambiente de alta umidade. ______________________________________________________________________________________ ABSTRACTThe objectives of the present study were to determine anatomical characteristics, mechanical
properties and natural durability to two fungi types [Gloeophyllum trabeum (Persoon ex Fries)
Murrill and Trametes versicolor (Linnaeus ex Fries)Pilat] for cypress wood (Cupressus spp.).
The wood has straight grain, brown to white color, medium texture, and moderate luster. It
also showed medium to low density, low shrinkage, and moderate dimensional stability. Lignin
content was relatively high, whereas extractive content was low. Cupressus spp. showed static
bending properties of 4.1 GPa for modulus of elasticity; 91.0 MPa for modulus of rupture;
1.8 MPa for internal bond; and 6357 and 4039 N for end and side Janka hardness, respectively.
All mechanical properties, in air-dry condition, were similar to those described to cypresses
and some Amazonian hardwood species. Cypress wood was ranked as highly resistant to the
brown-rot fungus Gloeophyllum trabeum and to the white-rot fungus Trametes versicolor,
making it suitable for interior and exterior uses and high humidity environment
Aedes albopictus pode não ser vetor da dengue durante epidemias no Brasil
Mais de 60.500 casos de dengue foram notificados no Espírito Santo, entre 1995 e 1998. Realizou-se estudo com o objetivo de averiguar se o mosquito Aedes albopictus estava transmitindo o vírus durante uma epidemia em Vila Bethânia (Viana), no sudeste de Vitória, capital capixaba. De 3 a 9 de abril de 1998, amostras de sangue e (ou) soro de pacientes foram coletadas e os mosquitos foram capturados diariamente, tanto para isolamento viral como para testes sorológicos. Em onze casos autóctonos, quatro foram confirmados por isolamento do vírus DEN 1, e dois por reação MAC ELISA Dos 37 Ae. aegypti e 200 Ae. albopictus adultos capturados e inoculados, apenas uma amostra de vírus DEN 1 foi obtida de um lote de duas fêmeas de Ae. aegypti. Os resultados sugerem que a espécie Ae. albopictus ainda não pode ser considerada um vetor inter-humano durante epidemias de dengue no Brasil.Over 60,500 dengue cases were reported in the state of Espírito Santo (ES), Brazil, between 1995 and 1998. The study's purpose was to identify whether Aedes albopictus was transmitting the dengue virus during an epidemic in the locality of Vila Bethânia (Viana County),Vitória, ES. From April 3 to 9, 1998, blood and serum samples were collected daily for virus isolation and serological testing. Four autochthonous cases were confirmed through DEN 1 virus isolation and two autochthonous cases through MAC ELISA testing. Of 37 Ae. aegypti and 200 Ae. albopictus adult mosquitoes collected and inoculated, DEN1 virus was isolated only from a pool of two Ae. aegypti female mosquitoes. The study results suggest that Ae. albopictus still cannot be considered an inter-human vector in dengue epidemics in Brazil
Infection of the lymphatic system by Aureobasidium pullulans in a patient with erythema nodosum leprosum
Aureobasidium pullulans is a causal agent of phaeohyphomycosis, occasionally found in men and animals. As an agent of different opportunistic fungal processes, it may cause fungemia, systemic infections and abscesses in different viscera. This paper aims to report a case of a patient with infection of the lymphatic system by A. pullulans. A 23-year-old patient being treated for erythema nodosum leprosum presented a 60-day complaint of daily fever, hoarseness, odynophagia and weight loss. Laboratory tests showed pancytopenia with severe neutropenia, cervical adenomegaly and solid contrast uptake lesion in the oropharyngeal region. Due to neutropenia and sepsis the patient was initially treated with cefepime and vancomycin, but there was no clinical improvement. Lymph node puncture-aspiration showed yeast-form fungus identified as A. pullulans by sequencing ITS region. The patient was treated with amphotericin B deoxycholate, leading to complete recovery of bone marrow function and regression of adenomegaly and the oropharyngeal lesion
High prevalence and mortality due to Histoplasma capsulatum in the Brazilian Amazon: An autopsy study
Background: Histoplasmosis is acquired by inhalation of spores of the dimorphic fungus Histoplasma spp. Although this pathogen is distributed worldwide, it is more prevalent in the Americas. However, the real burden of histoplasmosis remains undefined in many endemic regions. Methodology: We conducted a series of 61 autopsies to individuals who died in a hospital in the Brazilian Amazon focused on infectious diseases. We performed a detailed histological and microbiological evaluation with genetic characterization of Histoplasma strains with the aim to evaluate the contribution of histoplasmosis to morbidity and mortality. Additionally, we assessed the clinicopathological correlation. Principal findings: Evidence of Histoplasma infection was detected in 21 patients (34%). Eight cases were disseminated infections, all of them occurred in HIV-positive patients. Six cases were localized histoplasmosis, limited to the lungs. In seven patients Histoplasma DNA was detected by PCR in patients with no histological lesions. Histoplasma infection was detected in 38% of HIV-positive patients and was a major contributor to death in 22% of them. Lungs, liver and spleen were affected in all cases of disseminated histoplasmosis. Phylogenetic analysis of the strains suggested a high diversity of Histoplasma species circulating in the Brazilian Amazon. Histoplasmosis was clinically missed in 75% of the disseminated infections. Conclusions: The high incidence of histoplasmosis, the low index of clinical suspicion, and the severity of the disseminated disease highlight the need of proactively implementing sensitive routine screening methods for this pathogen in endemic areas. Antifungal prophylaxis against Histoplasma should be encouraged in the severely immunocompromised HIV patients in these areas. In conclusion, substantial mortality is associated with disseminated histoplasmosis among HIV-positive patients in the Brazilian Amazon
Genomic diversity of the human pathogen Paracoccidioides across the South American continent
Paracoccidioidomycosis (PCM) is a life-threatening systemic mycosis widely reported in the Gran Chaco ecosystem. The disease is caused by different species from the genus Paracoccidioides, which are all endemic to South and Central America. Here, we sequenced and analyzed 31 isolates of Paracoccidioides across South America, with particular focus on isolates from Argentina and Paraguay. The de novo sequenced isolates were compared with publicly available genomes. Phylogenetics and population genomics revealed that PCM in Argentina and Paraguay is caused by three distinct Paracoccidioides genotypes, P. brasiliensis (S1a and S1b) and P. restrepiensis (PS3). P. brasiliensis S1a isolates from Argentina are frequently associated with chronic forms of the disease. Our results suggest the existence of extensive molecular polymorphism among Paracoccidioides species, and provide a framework to begin to dissect the connection between genotypic differences in the pathogen and the clinical outcomes of the disease.Fil: Teixeira, Marcus de Melo. Universidade do Brasília; BrasilFil: Cattana, Maria Emilia. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Matute, Daniel R.. University of North Carolina; Estados UnidosFil: Muñoz, José F.. Broad Institute Of Mit And Harvard; Estados UnidosFil: Arechavala, Alicia. Hospital Francisco J Muñiz; ArgentinaFil: Isbell, Kristin. University of North Carolina; Estados UnidosFil: Schipper, Rafael. Universidade do Brasília; BrasilFil: Santiso, Gabriela Maria. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Tracogna, Fernanda. Gobierno de la Provincia de Chaco. Hospital Julio Cecilio Perrando.; ArgentinaFil: Sosa, María de los Ángeles. Universidad Nacional del Nordeste. Instituto de Medicina Regional; ArgentinaFil: Cech, Norma. Hospital 4 de Junio; ArgentinaFil: Alvarado, Primavera. Instituto de Biomedicina Dr. Jacinto Convit; VenezuelaFil: Barreto, Laura. Instituto Superior de Formación Docente Salome Ureña; República DominicanaFil: Chacón, Yone. Provincia de Salta. Ministerio de Salud Pública. Hospital del Milagro; ArgentinaFil: Ortellado, Juana. Universidad Nacional de Asunción; ParaguayFil: Lima, Cleoni Mendes de. Universidade Federal de Rondonia; BrasilFil: Chang, Marilene Rodrigues. Universidade Federal do Mato Grosso do Sul; BrasilFil: Niño Vega, Gustavo. Universidad de Guanajuato; MéxicoFil: Yasuda, Maria Aparecida Shikanai. Universidade de Sao Paulo; BrasilFil: Felipe, Maria Sueli Soares. Universidade Catolica de Brasilia; BrasilFil: Negroni, Ricardo. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Cuomo, Christina A.. Broad Institute of MIT And Harvard; Estados UnidosFil: Barker, Bridget. Tgen Northern Arizona University; Estados UnidosFil: Giusiano, Gustavo Emilio. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Universidad Nacional del Nordeste. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentin
Informação, política e fé: o jornal Mensageiro da Paz no contexto de redemocratização do Brasil (1980-1990)
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