Fungal microbiota dynamics as a postmortem investigation tool: focus on Aspergillus, Penicillium and Candida species.

AIMS: To investigate the presence of fungi during three human decomposition stages: bloated, putrefaction and skeletonization. METHODS AND RESULTS: The samples were gathered in the city of Fortaleza, Ceará, Brazil, from the public morgue and cemeteries. The material was submitted to conventional mycological procedures by direct examination and macro/micro morphological and biochemical analyses. The main fungi isolated were Aspergillus spp., Penicillium spp. and Candida spp. in the bloated stage (n = 34 cadavers) and in the putrefaction stage (n = 6 cadavers), while in the skeletonization stage (n = 20 cadavers), the main fungi were Aspergillus spp., Penicillium spp. and Mucor sp. CONCLUSIONS: Aspergillus, Penicillium and Candida species were associated with decomposed human cadavers. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings enable tracing out the profile of fungal communities of human cadavers for the first time. However, much more research will be necessary to develop this new segment of mycology and to enable its routine use in forensic science.

Ants (Hymenoptera: Formicidae) as carriers of fungi in hospital environments: an emphasis on the genera Tapinoma and Pheidole.

The aim of this study was to evaluate the presence of filamentous fungi and yeasts on the external surface of ants at hospitals. From March 2007 to February 2008, 2,899 ants were evaluated in two public hospitals in the city of Fortaleza, Ceará, in northeastern Brazil. The ants were attracted by nontoxic baits, distributed within critical and semicritical hospital areas. The fungi were identified through macro- and micromorphological analysis, biochemical profile, and growth in chromogenic medium. From this study, 5 genera and 13 species of ants were identified, from critical (8% of the collected ants) and semicritical (92%) areas, during the daytime (48%) and nighttime (52%) periods. In the mycological analysis, 75% of the ants were fungi carriers, with the species Tapinoma melanocephalum and species from the genus Pheidole having the most potential as carriers of airborne fungi (75 and 18%, respectively) and yeasts (6 and 1%, respectively). In summary, ants act as carriers of airborne fungi and yeasts, including some pathogenic species.

[Multiple antibiotic resistance mediated by R plasmid in Shigella flexneri strains isolated in the northeast of Brazil]. / Multirresistência a antimicrobianos mediada por plasmídios R em cepas de Shigella flexneri isoladas no nordeste do Brasil.

In Shigella strains were studied the molecular mechanism that mediated the multiply antibiotic-resistance. Twenty-six strains of Shigella flexneri were utilised in this investigation. These strains were submitted to disk diffusion test, mating experiments and plasmid isolation. In relation to antibiotics resistance standard it was observed that all Shigella flexneri strains were resistant to at least, three antibiotics tested. From twenty-six Shigella flexneri strains donors submitted to conjugation process, 34.6% (nine strains) resulted in variable frequency of transconjugants. From strains that conjugated, 100%, transferred the resistance factor acquainted with ampicillin. Being that, in all transconjugants which were observed, just one plasmid with 23.1 Kb was evidenced. This plasmid found in all strains was characterised as the cause of resistance to ampicillin.

Multirresistência a antimicrobianos mediada por plasmídios R em cepas de Shigella flexneri isoladas no nordeste do Brasil / Multiple antibiotic resistance mediated by R plasmid in Shigella flexneri strains isolated in the northeast of Brazil

Em amostras de S. flexneri, isoladas no período de 1989 a 1993, foi estudado o mecanismo molecular que mediava a multirresistência. Foram utilizadas no estudo 26 amostras de S. flexneri. Estas amostras foram submetidas a teste de sensibilidade a antimicrobianos, experimentos de conjugação e extração de plasmídios. Com relação ao padrão de resistência a antimicrobianos, observou-se que todas as amostras de S. flexneri eram resistentes a pelo menos três antimicrobianos. Das 26 amostras de S. flexneri doadoras submetidas ao processo de conjugação, 34,6% (9 amostras) resultaram em uma freqüência variável de transconjugantes. Das amostras que conjugaram, 100% transferiram o fator de resistência relacionado à ampicilina; sendo que em todas as transconjugantes foi evidenciado apenas um plasmídio de 23,1Kb. Este plasmídio, encontrado em todas as amostras de Shigellas, caracterizou-se como o portador de marca de resistência para ampicilina.

In Shigella strains were studied the molecular mechanism that mediated the multiply antibiotic-resistance. Twenty-six strains of Shigella flexneri were utilised in this investigation. These strains were submitted to disk diffusion test, mating experiments and plasmid isolation. In relation to antibiotics resistance standard it was observed that all Shigella flexneri strains were resistant to at least, three antibiotics tested. From twenty-six Shigella flexneri strains donors submitted to conjugation process, 34.6% (nine strains) resulted in variable frequency of transconjugants. From strains that conjugated, 100%, transferred the resistance factor acquainted with ampicillin. Being that, in all transconjugants which were observed, just one plasmid with 23.1 Kb was evidenced. This plasmid found in all strains was characterised as the cause of resistance to ampicillin.