THE POWER OF THE SMALL: THE EXAMPLE OF Paracoccidioides brasiliensis CONIDIA / O poder do pequeno: o exemplo dos conídios do Paracoccidioides brasiliensis

SUMMARYResearch on Paracoccidioides brasiliensis has centered in the yeast cell probably because of the lack of distinctive features in the mycelium. In 1942 and for the first time, lateral conidia were noticed in the fungus' hyphae. Later on, Brazilian, Venezuelan and Argentinean researchers described "aleurias" when the fungus was grown in natural substrates. In 1970 authors became interested in the conidia and were able to obtain them in large numbers and treat them as individual units. Their shape and size were defined and the presence of all the elements of a competent eukaryotic cell were demonstrated. Conidia exhibited thermal dimorphism and, additionally, when given intranasally to BALB/c male mice, they converted into yeasts in the lungs and produce progressive pulmonary lesions with further dissemination to other organs. Studies on the phagocyte-conidia interaction were revealing and showed that these versatile structures allow a better understanding of the host- P. brasiliensisinteractions.

RESUMOA investigação sobre Paracoccidioides brasiliensis tem-se centrado na célula de levedura, provavelmente devido à falta de características distintas no micélio. Em 1942 e, pela primeira vez, conídios laterais foram notados nos hifas dos fungos. Mais tarde, pesquisadores brasileiros, venezuelanos e argentinos descreveram "aleurias" quando o fungo foi cultivado em substratos naturais. Em 1970, os autores se interessaram pelos conídios e foram capazes de obtê-los em grande número e tratá-los como unidades individuais. A sua forma e tamanho foram definidos, e a presença de todos os elementos de uma célula eucariótica competente foram demonstrados. Conídios apresentam dimorfismo térmico e, além disso, quando administrados por via intranasal a camundongos BALB/c machos, são convertidos em leveduras nos pulmões e produzem lesões pulmonares progressivas com posterior disseminação para outros órgãos. Estudos sobre a interação de fagócitos-conídios foram reveladores e mostraram que estas estruturas versáteis permitem melhor compreensão das interacções entre hospedeiro e P. brasiliensis.

Desinfectantes en aerosol como alternativa de control ambiental de los hongos anemófilos en viviendas / Disinfectant spray as an alternative environmental control of airborne fungi in houses

El objetivo de este trabajo fue evaluar el efecto de productos desinfectantes comerciales en aerosol sobre la carga de hongos ambientales en habitaciones de viviendas, teniendo en cuenta que las personas, principalmente los niños, pasan la mayor parte del día en las mismas. Además, se estudió, a través de encuestas, las preferencias del público a la hora de adquirir los desinfectantes comerciales ensayados. El número de UFC/placa fue variable dentro de la misma habitación para las distintas mediciones realizadas antes de la aplicación de los productos desinfectantes. Los porcentajes de inhibición del crecimiento fúngico fueron variables dependiendo del producto desinfectante ensayado y de la habitación muestreada. Dichos porcentajes no fueron diferentes significativamente entre los desinfectantes. Los valores de temperatura estuvieron dentro de un rango de 11 a 19,5 ºC y el porcentaje de humedad relativa varió entre un 64 a 85 por ciento. El 89 por ciento de los encuestados conocía la existencia de desinfectantes ambientales en aerosol. El 78 por ciento conocía el Lysoform®, seguido por Glade® antitabaco y Ayudin®. Dentro de los productos más utilizados, el 54 por ciento de los encuestados indicó el producto Lysoform®. La mayoría de los consumidores eligieron a los desinfectantes por lo que conocen y los medios de comunicación influyeron en el 29 por ciento de los consumidores al momento de elegir el desinfectante. Estos productos ensayados son recomendables en una habitación para disminuir la carga de hongos ambientales y así reducir el efecto perjudicial de estos hongos sobre las personas que la utilizan.

The aim of this study was to evaluate the effect of commercial disinfectant spray on the concentration of airborne fungi in bedrooms, considering that people, especially children, spend most of the day in them. Also, public preferences through surveys were studied when acquiring commercial disinfectants tested. The number of CFU/Petri dish was variable within the same bedroom for the different measurements performed before application of the disinfectant. Percent inhibition of fungal growth were variable, depending on the disinfecting product tested and sampled bedroom. These percentages were not significantly different between the disinfectants. The temperature values were within a range of 11 to 19.5° C and relative humidity percentage ranged from 64 to 85 percent. Eighty nine percent of respondents knew about environmental disinfectant spray. Seventy-eight percent knew about Lysoform®, followed by antismoking Glade® and Ayudin®. Among the most widely used products, 54 percent of respondents said the Lysoform® product was the most used. Most consumers chose known disinfectants and, when choosing a disinfectant, the media influenced 29 percent of consumers. The used products are recommended to be used in a bedroom to decrease the number of airborne fungi and thus reduce the harmful effect of these fungi on the people that use this room.

Relación in vitro entre cylindrocarpon cylindroides y neonectria fuckeliana asociados a cancros fustales de pinus radiata en Chile / In vitro relationship between cylindrocarpon cylindroides and neonectria fuckeliana associated with stem cankers on pinus radiata in Chile

Desde el punto de vista estrictamente micológico, se ha discutido por décadas la relación de Cylindrocarpon cylindroides como anamorfo de Neonectria fuckeliana, lo que entre otras consecuencias, ha incidido en la controversial ubicación taxonómica de este teleomorfo. Se añade a esto que en patología forestal se ha brindado poca atención a la presencia de C. cylindroides dentro del ciclo de la enfermedad causada por Neonectria fuckeliana en coníferas, razón por la cual los estudios específicos respecto de este anamorfo han sido también muy escasos. El presente trabajo tuvo como objetivo verificar la relación entre C. cylindroides y Neonectria fuckeliana, asociados a cancros en troncos de Pinus radiata en Chile, mediante el análisis de las características macro y micromorfológicas que ellos manifiestan en cultivos in vitro, además de análisis de tipo molecular. Se pudo constatar que ambos agentes dieron origen a colonias con idénticas características macro y micromorfológicas, destacando entre éstas la producción de abundantes conodióforos y microconidios del tipo Acremonium, el cual ya ha sido señalado en anteriores estudios como estado anamorfo de Neonectria fuckeliana. El que este mismo estado asexual del tipo Acremonium haya sido la manifestación in vitro tanto de C. cylindroides como de Neonectria fuckeliana, permitió confirmar la relación existente entre estos dos agentes en estudio, la que también fue ratificada mediante los análisis moleculares realizados.

From the point of view strictly mycological has been discussed for decades the relationship of Cylindrocarpon cylindroides as anamorph of Neonectria fuckeliana, which among other consequences, has influenced the controversial taxonomic status of this teleomorph. Add to this that in forest pathology has given little attention to the presence of C. cylindroides within the cycle of the disease caused by Neonectria fuckeliana on conifers, why specific studies regarding this anamorph have been very few. This study aimed to verify the relationship between C. cylindroides and Neonectria fuckeliana associated with cankers on trunks of Pinus radiata in Chile, by analyzing the macro and micromorphological characteristics they manifest in cultures in vitro, further analysis type molecular. It was found that both agents gave rise to colonies with identical macro and micromorphological characteristics, highlighting among them the production of abundant microconidia and conidiophores of Acremonium type, which has already been noted in previous studies as anamorph state of Neonectria fuckeliana. The asexual state that this same type of Acremonium has been the in vitro demons-tration of both C. cylindroides as Neonectria fuckeliana, allowed us to confirm the relationship between these two agents in the study, which was also ratified by the molecular analyzes performed.

Detección del sinanamorfo Cylindrocarpon cylindroides var. Tenue sobre cancros causados por Neonectria fuckeliana en Pinus radiata / Detection of sinanamorph Cylindrocarpon cylindroides var. tenue on Neonectria fuckeliana cankers in Pinus radiata

El presente trabajo tuvo por finalidad reportar y analizar la presencia de estructuras fungosas (esporodoquios) sobre cancros causados por Neonectria fuckeliana en árboles de Pinus radiata en Chile. Las muestras fueron colectadas en las Regiones de La Araucanía y de Los Ríos y fueron analizadas en el laboratorio. Los resultados de los análisis morfológicos y taxonómicos permitieron concluir que los esporodoquios hallados correspondían al sinanamorfo de Neonectria fuckeliana (forma cylindrocarpon cylindroides var tenue), siendo el primer reporte en el país. Estos antecedentes contribuyen al conocimiento y comprensión del ciclo patológico y epidemiológico de Neonectria fuckeliana en plantaciones de Pinus radiata.

The present work was aimed at reporting and analyzing the presence of fungal structures (sporodochia) present on cankers caused by Neonectria fuckeliana in Pinus radiata trees in Chile. The samples were collected in the regions of La Araucanía and Los Ríos and analyzed in the laboratory. The results of morphological and taxonomic analysis led to the conclusion that thesporodochia found corresponded to sinanamorph of Neonectria fuckeliana (cylindrocarpon cylindroides var. tenue morph), the first report in the country. This work contribute to understanding and comprehension of the disease cycle and epidemiology of Neonectria fuckeliana on plantations of Pinus radiata.

Antifungal activity of extracts from Brazilian Cerrado plants on Colletotrichum gloeosporioides and Corynespora cassiicola / Atividade antifúngica de extratos de plantas do Cerrado brasileiro sobre Colletotrichum gloeosporioides e Corynespora cassiicola

This study aimed to determine the antifungal activity of leaf aqueous and hydroethanolic extracts of 10 plants from the Brazilian Cerrado on Colletotrichum gloeosporioides and Corynespora cassiicola. Antifungal activity was measured through the incorporation of each extract in a culture media or spore suspension, at 50 percent concentration relative to the volume, determining respectively the mycelial growth and the spore germination. Then, the percentages of mycelial growth inhibition and spore germination inhibition were obtained based on the comparison with the control. The extracts had a variable action on the phytopathogens, from mycelial growth stimulation for Aristolochia esperanzae and Byrsonima verbascifolia extracts to complete inhibition of mycelial growth and spore germination for Myracrodruon urundeuva and Lafoensia pacari extracts. M. urundeuva, L. pacari and Caryocar brasiliense leaf extracts had antifungal activity against Colletotrichum gloeosporioides and Corynespora cassiicola; the hydroethanolic extracts presented more antifungal activity than the aqueous extracts, and spore germination of both phytopathogens was more affected than their mycelial growth.

O objetivo deste trabalho foi determinar a atividade antifúngica de extratos aquosos e extratos hidroetanólicos de folhas de 10 plantas do Cerrado brasileiro sobre Colletotrichum gloeosporioides e Corynespora cassiicola. A determinação da atividade antifúngica foi realizada pela incorporação do extrato em meio de cultura ou na suspensão de esporos, na concentração de 50 por cento em relação ao volume, determinando-se, respectivamente, o crescimento micelial e a germinação de esporos. Em seguida, pela comparação com a testemunha, foram obtidas as percentagens de inibição do crescimento micelial e da germinação dos esporos. Foi constatado comportamento variável dos extratos sobre os fitopatógenos, desde o estímulo no crescimento micelial para os extratos de Aristolochia esperanzae e Byrsonima verbascifolia, até a inibição completa do crescimento micelial e dagerminação dos esporos para os extratos de Myracrodruon urundeuva e Lafoensia pacari. Extratos de folhas de L. pacari, de M. urundeuva e de Caryocar brasiliense apresentaram atividade antifúngica sobre Colletotrichum gloeosporioides e Corynespora cassiicola; os extratos hidroetanólicos proporcionaram mais atividade antifúngica que os extratos aquosos, e a germinação de esporos de ambos os fitopatógenos foi mais afetada que o crescimento micelial.

Adiaspiromicose pulmonar humana / Human pulmonary adiaspiromycosis

A adiaspiromicose é uma doença fúngica sistêmica que acomete usualmente roedores e raramente atinge o homem. É causada pelo fungo Emmonsia crescens e ocorre após a inalação da forma contagiante (conídios). Embora estas formas não se multipliquem nem se disseminem no organismo humano, induzem uma reação inflamatória crônica granulomatosa de padrão miliar que pode levar a falência respiratória e morte. Apresentamos aqui um caso de adiaspiromicose pulmonar humana em paciente imunocompetente que exibia infiltrado intersticial pulmonar difuso ao exame de imagem e fora diagnosticado mediante biópsia pulmonar.

Adiaspiromycosis is a systemic fungal disease that usually affects rodents and rarely infects humans. It is caused by the fungus Emmonsia crescens and occurs after inhalation of its contagious form (conidia). Although these forms neither multiply nor spread in the human body, they cause a chronic granulomatous inflammatory reaction of miliary pattern, which may lead to respiratory failure and death. In this study we present a case of human pulmonary adiaspiromycosis in an immunocompetent patient that showed a diffuse pulmonary interstitial infiltrate diagnosed by pulmonary biopsy.

Efecto de la calidad del agua de criaderos de mosquitos (Diptera: Culicidae) sobre la patogenicidad e infectividad de las zoosporas del hongo Leptolegnia chapmanii (Straminipila: Peronosporomycetes)

Effect of water quality in mosquito breeding sites on the pathogenicity and infectivity of zoospores from the fungus Leptolegnia chapmanii (Straminipila: Peronosporomycetes). The fungus Leptolegnia chapmanii is highly pathogenic to mosquito larvae in Argentina. We studied if physical and chemical characteristics of the water from mosquito breeding sites affect pathogenicity, and the infectivity of zoospores of L. chapmanii. Water samples were taken from pools filled by rains, urban ditches with domestic waste water, pools filled by overflow from Río de la Plata, and flower vases from the Cemetery of La Plata city. Sub-samples of water were analyzed for physical and chemical characteristics, while other sub-samples were used for laboratory bioassays. Containers with 150 ml of water samples, 25 Aedes aegypti larvae, and 2.8 x 105 zoospores of L. chapmanii, were incubated under controlled environment, and larval mortality was recorded after 48 h. There were highly significant differences among mortalities in water from cemetery vases (70.2%), rain pools water (99.5%), and pools with water from Rio de la Plata (95%). There were no significant differences among larval mortalities in water from ditches, rain pools and Río de la Plata pools. Leptolegnia chapmanii was successful as a biological control agent in all kinds of tested water qualities, producing high larval mortality. Rev. Biol. Trop. 57 (1-2): 371-380. Epub 2009 June 30.

Leptolegnia chapmanii es un potente patógeno de larvas de mosquitos. El objetivo del trabajo fue determinar si las características físico-químicas del agua de criaderos de culícidos de importancia sanitaria a nivel mundial afectan la patogenicidad e infectividad de las zoosporas de L. chapmanii. Se tomaron muestras de cuatro tipos de agua en Argentina: de lluvia, de zanja, del Río de La Plata, y de floreros del cementerio local. A una parte del agua se le realizaron estudios físicos-químicos, y otra parte fue utilizada en ensayos. Se colocó 150 ml de cada muestra en recipientes plásticos, con 25 larvas sanas de Aedes aegypti y 2.8 x 105 zoosporas de L. chapmanii. Fueron incubadas a 25 ºC y 12-12 (L-O). La mortalidad larval fue registrada a las 48 horas. Se utilizaron tres recipientes y un control por tratamiento, con tres repeticiones realizadas en distintos días. Se observaron diferencias altamente significativas entre la mortalidad larval en aguas de floreros del cementerio (70.2%), aguas de lluvias (99.53%), y del río de La Plata (95%). No hubo diferencias significativas entre la mortalidad larval en agua de zanja, lluvia y río. Leptolegnia chapmanii resultó exitoso en los cuatro tipos de aguas evaluados, produciendo elevados niveles de mortalidad larval.

Growth of in vitro Fusarium oxysporum f. sp. niveum in chemically defined media amended with gallic acid

Gallic acid was artificially added to the media to grow Fusarium oxysporum f.sp.niveum to investigate its effect on the pathogenic fungus. Results indicate that gallic acid inhibited the growth of F. oxysporum f.sp.niveum. The colony diameter, the conidia germinating rate and the conidia yield were reduced by 5.7-22.9 percent percent, 35.8-55.6 percent and 38.9-62.2 percent respectively. However, the virulence factors by the fungus were stimulated. The activity of pectinase, proteinase and cellulase increased by 12.3-627.8 percent, 11.8-41.2 percent and 0.5-325.0 percent respectively, while the activity of amylase increased slightly. The results suggest that gallic acid repressed growth but facilitated the relative pathogenicity of invading pathogens.

Micoflora anemófila de la ciudad de Resistencia (Chaco) / Anemophila mycoflora of the Resistencia city (Chaco)

Se estudió mediante la técnica de placas de agar abiertas, la presencia de hongos en 120 muestras de aire atmosférico de la ciudad de Resistencia (Argentina) tomadas en 12 lugares con gran movimiento de personas y vehículos. Los cultivos se realizaron sobre medio de Agar-papa-rifamicina a 28 y a 42ºC a fin de aislar especies mesófilas y termófilas. Se obtuvo desarrollo de hongos en todas las placas incubadas a 28ºC (100 por ciento de positividad), mientras que las incubadas a 42ºC sólo en una hubo desarrollo, correspondiendo a A. fumigatus. Se aisló un total de 20 géneros micológicos, de los cuales se pudieron identificar 19 especies, quedando 3 aislados sin clasificación definitiva por tratarse de micelio estéril hialino, micelio amarillo con clamidosporas y micelio con picnidios. Las especies aisladas se clasificaron según sus frecuencias de aparición, de acuerdo al criterio de Yadav y Madelin en: muy comunes, frecuentes ocasionales y raras. Los géneros dominantes en la micobiota atmosférica estudiada fueron: Alternaria, Fusarium, Drechslera y Aspergillus que se presentaron en el 100 por ciento de las muestras, seguidos por Penicillium, Cladosporium, Curvularia y Rhodotorula que aparecieron en el 75 por ciento, 66,7 por ciento y 58,3 por ciento, respectivamente. Los resultados obtenidos revelan la existencia de una alta carga de esporas fúngicas en la atmósfera de la ciudad de Resistencia