Chlamydospore formation by Paracoccidioides brasiliensis mycelial form

To investigate the role of some adverse environmental conditions in chlamy-dospore formation by the mycelial form of P. brasiliensis, we cultured four P. brasiliensis isolates (18, Bt4, 1183, Pb9) at 25°C within solid agar medium either rich or poor in nutrients. Isolates 18 and 1183 were also cultured under anaerobiosis in a nitrogen atmosphere. Isolate 18 produced great number of terminal and intercalary chlamydospore after 7-10 days of culture in a medium poor in nutrients (2% agar with 0.1% dextrose and polypepton). The three other isolates also produced chlamydospores under the same conditions, but in lower numbers. Chlamydospore production by isolate 18 was abolished when the fungus was cultured in two agar media rich in nutrients (brain heart infusion and potato dextrose agar). Anaerobic incubation of isolate 18 under an atmosphere of N2 showed small mycelial outgrowth with numerous chlamydospores. At the electron microscopical level, the chlamydospores showed one or various nuclei and numerous mitochondria, indicating great potential for further development. Accordingly, chlamydospores produced multiple budding after only 24 h incubation at 35°C. The results demonstrate that under adverse environmental conditions P. brasiliensis mycelial form produces chlamydospores within a short period of time

Proyecto de prevención de drogodependencias

Se pretende que los alumnos adopten estilos de vida saludables, que sean autónomos en sus decisiones y que eviten conductas dependientes como el consumo de drogas. Contiene los objetivos y contenidos por áreas para Primaria y Secundaria relacionados con el proyecto, y las propuestas de intervención en los distintos ámbitos: Consejo Escolar, Departamentos de orientación, Comisión de Coordinación Pedagógica, alumnos, profesores, familias y municipio de Pinto. Incluye varios cuadros con la temporalización y secuenciación de actividades, a quién van dirigidos, y con los aspectos e indicadores de evaluación. En anexos adjunta cinco unidades didácticas por ciclos, para Primaria y Secundaria, sobre alimentación, higiene, tabaco y drogas.Madrid (Comunidad Autónoma). Consejería de Educación y Cultura. Ministerio de Educación y Cultura. Ayuntamiento de MadridMadridMadrid (Comunidad Autónoma). Subdirección General de Formación del Profesorado. CRIF Las Acacias; General Ricardos 179 - 28025 Madrid; Tel. + 34915250893ES

Comparative Transcriptomics of the Saprobic and Parasitic Growth Phases in <em>Coccidioides</em> spp

<div><p><em>Coccidioides immitis</em> and <em>C. posadasii</em>, the causative agents of coccidioidomycosis, are dimorphic fungal pathogens, which grow as hyphae in the saprobic phase in the environment and as spherules in the parasitic phase in the mammalian host. In this study, we use comparative transcriptomics to identify gene expression differences between the saprobic and parasitic growth phases. We prepared Illumina mRNA sequencing libraries for saprobic-phase hyphae and parasitic-phase spherules <em>in vitro</em> for <em>C. immitis</em> isolate RS and <em>C. posadasii</em> isolate C735 in biological triplicate. Of 9,910 total predicted genes in <em>Coccidioides</em>, we observed 1,298 genes up-regulated in the saprobic phase of both <em>C. immitis</em> and <em>C. posadasii</em> and 1,880 genes up-regulated in the parasitic phase of both species. Comparing the saprobic and parasitic growth phases, we observed considerable differential expression of cell surface-associated genes, particularly chitin-related genes. We also observed differential expression of several virulence factors previously identified in <em>Coccidioides</em> and other dimorphic fungal pathogens. These included alpha (1,3) glucan synthase, SOWgp, and several genes in the urease pathway. Furthermore, we observed differential expression in many genes predicted to be under positive selection in two recent <em>Coccidioides</em> comparative genomics studies. These results highlight a number of genes that may be crucial to dimorphic phase-switching and virulence in <em>Coccidioides</em>. These observations will impact priorities for future genetics-based studies in <em>Coccidioides</em> and provide context for studies in other fungal pathogens.</p> </div