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1.
Int J Syst Evol Microbiol ; 72(10)2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36314898

RESUMEN

As currently circumscribed, Acrogenospora (Acrogenosporaceae, Minutisphaerales, Dothideomycetes) is a genus of saprobic hyphomycetes with distinctive conidia. Although considered common and cosmopolitan, the genus is poorly represented by sequence data, and no neotropical representatives are present in public sequence databases. Consequently, Acrogenospora has been largely invisible to ecological studies that rely on sequence-based identification. As part of an effort to identify fungi collected during ecological studies, we identified strains of Acrogenospora isolated in culture from seeds in the soil seed bank of a lowland tropical forest in Panama. Here we describe Acrogenospora terricola sp. nov. based on morphological and phylogenetic analyses. We confirm that the genus has a pantropical distribution. The observation of Acrogenospora infecting seeds in a terrestrial environment contrasts with previously described species in the genus, most of which occur on decaying wood in freshwater environments. This work highlights the often hidden taxonomic value of collections derived from ecological studies of fungal communities and the ways in which rich sequence databases can shed light on the identity, distributions and diversity of cryptic microfungi.


Asunto(s)
Ascomicetos , Banco de Semillas , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Bosques , Filogenia , ARN Ribosómico 16S/genética , Semillas/microbiología , Análisis de Secuencia de ADN , Suelo , Clima Tropical , Panamá
2.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34731078

RESUMEN

A growing interest in fungi that occur within symptom-less plants and lichens (endophytes) has uncovered previously uncharacterized species in diverse biomes worldwide. In many temperate and boreal forests, endophytic Coniochaeta (Sacc.) Cooke (Coniochaetaceae, Coniochaetales, Sordariomycetes, Ascomycota) are commonly isolated on standard media, but rarely are characterized. We examined 26 isolates of Coniochaeta housed at the Gilbertson Mycological Herbarium. The isolates were collected from healthy photosynthetic tissues of conifers, angiosperms, mosses and lichens in Canada, Sweden and the United States. Their barcode sequences (nuclear ribosomal internal transcribed spacer and 5.8S; ITS rDNA) were ≤97% similar to any documented species available through GenBank. Phylogenetic analyses based on two loci (ITS rDNA and translation elongation factor 1-alpha) indicated that two isolates represented Coniochaeta cymbiformispora, broadening the ecological niche and geographic range of a species known previously from burned soil in Japan. The remaining 24 endophytes represented three previously undescribed species that we characterize here: Coniochaeta elegans sp. nov., Coniochaeta montana sp. nov. and Coniochaeta nivea sp. nov. Each has a wide host range, including lichens, bryophytes and vascular plants. C. elegans sp. nov. and C. nivea sp. nov. have wide geographic ranges. C. montana sp. nov. occurs in the Madrean biome of Arizona (USA), where it is sympatric with the other species described here. All three species display protease, chitinase and cellulase activity in vitro. Overall, this study provides insight into the ecological and evolutionary diversity of Coniochaeta and suggests that these strains may be amenable for studies of traits relevant to a horizontally transmitted, symbiotic lifestyle.


Asunto(s)
Ascomicetos , Filogenia , Animales , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Canadá , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Endófitos/clasificación , Endófitos/aislamiento & purificación , Técnicas de Tipificación Micológica , Análisis de Secuencia de ADN , Suecia , Estados Unidos
3.
PLoS One ; 11(5): e0155622, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27187192

RESUMEN

The ophiostomatoid fungi (Microascales and Ophiostomatales, Ascomycota) are common associates of Ips typographus, and include tree pathogens and species responsible for blue-stain of timber. Fungal assemblages associated with I. typographus have varied considerably between studies but few investigations have attempted to explain this variation. For this reason, we assessed the overall cultivable fungal diversity associated with I. typographus in a storm-felled spruce forest in south-eastern Finland. Fungi were isolated from the individually collected beetles as well as their phoretic mites in spring, summer and autumn, including different life stages of the beetle (hibernation, dispersal flight and first generation). The internal transcribed spacer (ITS) gene region was used to identify the fungi. A total of 32 operational taxonomic units (OTUs) were found and these resided in four fungal phyla/subphyla (24 Ascomycota, 2 Basidiomycota, 5 Mucoromycotina, 1 Mortierellomycotina) in association with adult bark beetles. Ophiostomatoid species were the most commonly detected fungal associates. A generalized linear model analysis showed a clear association between fungal communities and season, indicating seasonal succession among I. typographus-associated fungi. The season of sampling appears to be an important factor that has resulted in inconsistencies between results in previous studies. Many of these fungi were also found on phoretic mites and their presence or absence could have influenced variation in patterns of association.


Asunto(s)
Escarabajos/microbiología , Hongos/aislamiento & purificación , Ácaros/microbiología , Animales , Finlandia , Hongos/clasificación , Picea/parasitología , Estaciones del Año , Simbiosis
4.
Int J Behav Nutr Phys Act ; 10: 102, 2013 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-23967799

RESUMEN

BACKGROUND: A large percentage (68%) of children under age 3 use screen media, such as television, DVDs and video games, on a daily basis. Research suggests that increased screen time in young children is linked to negative health outcomes, including increased BMI, decreased cognitive and language development and reduced academic success. Reviews on correlates of screen time for young children have included preschool age children and children up to age 7; however, none have focused specifically on correlates among infants and toddlers. As research suggests that screen media use increases with age, examining correlates of early media exposure is essential to reducing exposure later in life. Thus, this paper systemically reviews literature published between January 1999 and January 2013 on correlates of screen time among children between 0 and 36 months of age. METHODS: Two methods were used to conduct this review: (1) Computerized searches of databases (PubMed, PsycINFO, ERIC, Medline); and (2) Reference sections of existing reviews and primary studies. Inclusion criteria were: (1) The article included separate data for children 36 months and younger, (2) English language, (3) peer reviewed article, (4) analysis reported for screen viewing as a dependent variable, (5) original research article and, (6) examined correlates or associations between screen time and other demographic, contextual or behavioral variables. Articles were compiled between 2011 and 2013 and evaluation occurred in 2012 and 2013. RESULTS: The literature search identified 29 studies that met inclusion criteria. These studies investigated a total of 33 potential correlates, which were examined in this review. Findings suggest demographic variables most commonly correlated with high screen time among infants and toddlers are child's age (older) and race/ethnicity (minority). Child BMI, maternal distress/depression, television viewing time of the mother and cognitive stimulation in the home environment were also associated with screen media use. Studies reported that child sex, first born status, paternal education, non-English speaking family, two-parent household, number of children in the home and non-parental childcare were not associated with screen time among children aged 0-36 months. Associations were unclear (fewer than 60% of studies report an association) for maternal age, maternal education and household income. The remaining correlates were investigated in fewer than three studies and thus not coded for an association. CONCLUSIONS: The correlates identified in this study point to avenues for intervention to reduce screen time use in young children. However, further research is necessary to explore a number of environmental, socio-cultural and behavioral correlates that are under-examined in this population and may further inform prevention and intervention strategies.


Asunto(s)
Televisión , Factores de Edad , Índice de Masa Corporal , Preescolar , Etnicidad , Composición Familiar , Femenino , Humanos , Masculino , Padres/psicología , Medición de Riesgo , Factores Socioeconómicos
5.
Clin Pediatr (Phila) ; 52(9): 857-65, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23820003

RESUMEN

This study examined the association between screen media use, media content, and language development among 119 Hispanic infants and toddlers. Children and their caregivers were recruited through an urban, Early Head Start program. Duration and content of screen media exposure was measured through a 24-hour recall questionnaire, and language development was measured at baseline and at 1-year follow up. Children in the sample spent an average of 3.29 hours engaged with screen media (median 2.5 hours per day). In both cross-sectional and longitudinal analyses, children who watched over 2 hours of television per day had increased odds of low communication scores. Whereas child-directed media was associated with low language scores, adult-directed media was not. Our findings support the mounting literature on the deleterious impacts of screen media in toddler's language development. Guidance and alternatives to screen media use should be available to families in pediatric practices and early childhood centers.


Asunto(s)
Desarrollo del Lenguaje , Televisión/estadística & datos numéricos , Preescolar , Estudios Transversales , Femenino , Estudios de Seguimiento , Hispánicos o Latinos , Humanos , Lactante , Estudios Longitudinales , Masculino , Factores Socioeconómicos , Encuestas y Cuestionarios , Factores de Tiempo , Población Urbana/estadística & datos numéricos
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