Phenotypic and genotypic characteristics of Escherichia coli strains of non-enteropathogenic E-coli (EPEC) serogroups that carry eae and lack the EPEC adherence factor and shiga toxin DNA probe sequences

This study was conducted to characterize the virulence potential of 59 Escherichia coli strains carrying eae and lacking the enteropathogenic E. coli adherence factor and Shiga toxin probe sequences. in hybridization studies, all strains carried the locus of enterocyte effacement (LEE)-associated DNA sequences. of the other 15 virulence DNA sequences tested, hly was the most frequent (44.1%); 17 combinations of these sequences were found, but strains carrying eae only (eae profile) were the most frequent (35.6%). Except for 1 cytodetaching strain, all others adhered to HeLa and Caco-2 cells, most of which (similar to 75.0%) showed variations of the localized adherence pattern. Actin accumulation was detected in 75.9% of the nondetaching strains. Most strains had LEE, probably inserted in pheU (49.2%), and presented a nontypeable intimin (83.1%). Translocated intimin receptor-derived DNA sequences correlated with enteropathogenic and enterohemorrhagic E. coli in 61.0% and 32.0% of the strains, respectively. Thirty-five different serotypes were found. Only strains with the eae profile were associated with diarrhea (P = .039).Universidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilUniv São Paulo, Inst Butantan, Lab Especial Microbiol, São Paulo, BrazilUniv São Paulo, Inst Adolfo Lutz, Secao Bacteriol, São Paulo, BrazilUniv São Paulo, Hosp Clin, Inst Crianca, São Paulo, BrazilUniv Estado Rio de Janeiro, Dept Microbiol, Rio de Janeiro, BrazilUniv London Imperial Coll Sci Technol & Med, Dept Biochem, London, EnglandUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilWeb of Scienc

Landscape - wildfire interactions in southern Europe: implications for landscape management

ReviewEvery year approximately half a million hectares of land are burned by wildfires in southern Europe, causing large ecological and socio-economic impacts. Climate and land use changes in the last decades have increased fire risk and danger. In this paper we review the available scientific knowledge on the relationships between landscape and wildfires in the Mediterranean region, with a focus on its application for defining landscape management guidelines and policies that could be adopted in order to promote landscapes with lower fire hazard. The main findings are that (1) socio-economic drivers have favoured land cover changes contributing to increasing fire hazard in the last decades, (2) large wildfires are becoming more frequent, (3) increased fire frequency is promoting homogeneous landscapes covered by fire-prone shrublands; (4) landscape planning to reduce fuel loads may be successful only if fire weather conditions are not extreme. The challenges to address these problems and the policy and landscape management responses that should be adopted are discussed, along with major knowledge gapsinfo:eu-repo/semantics/publishedVersio

Chromosome evolution in Cophomantini (Amphibia, Anura, Hylinae)

The hylid tribe Cophomantini is a diverse clade of Neotropical treefrogs composed of the genera Aplastodiscus, Boana, Bokermannohyla, Hyloscirtus, and Myersiohyla. The phylogenetic relationships of Cophomantini have been comprehensively reviewed in the literature, providing a suitable framework for the study of chromosome evolution. Employing different banding techniques, we studied the chromosomes of 25 species of Boana and 3 of Hyloscirtus; thus providing, for the first time, data for Hyloscirtus and for 15 species of Boana. Most species showed karyotypes with 2n = 2x = 24 chromosomes; some species of the B. albopunctata group have 2n = 2x = 22, and H. alytolylax has 2n = 2x = 20. Karyotypes are all bi-armed in most species presented, with the exception of H. larinopygion (FN = 46) and H. alytolylax (FN = 38), with karyotypes that have a single pair of small telocentric chromosomes. In most species of Boana, NORs are observed in a single pair of chromosomes, mostly in the small chromosomes, although in some species of the B. albopunctata, B. pulchella, and B. semilineata groups, this marker occurs on the larger pairs 8, 1, and 7, respectively. In Hyloscirtus, NOR position differs in the three studied species: H. alytolylax (4p), H. palmeri (4q), and H. larinopygion (1p). Heterochromatin is a variable marker that could provide valuable evidence, but it would be necesserary to understand the molecular composition of the C-bands that are observed in different species in order to test its putative homology. In H. alytolylax, a centromeric DAPI+ band was observed on one homologue of chromosome pair 2. The band was present in males but absent in females, providing evidence for an XX/XY sex determining system in this species. We review and discuss the importance of the different chromosome markers (NOR position, C-bands, and DAPI/CMA3 patterns) for their impact on the taxonomy and karyotype evolution in Cophomantini

Enteropathogenic escherichia-coli O111AB-H2 penetrates the small-bowel epithelium in an infant with acute Diarrhea

ESCOLA PAULISTA MED,CTR ELECTRON MICROSCOPY & MICROBIOL,São Paulo,BRAZILUNIV BRASILIA,DEPT PAEDIAT,BR-70910 BRASILIA,DF,BRAZILUNIV ESTADUAL CAMPINAS,DEPT MICROBIOL & IMMUNOL,CAMPINAS,SP,BRAZILESCOLA PAULISTA MED,CTR ELECTRON MICROSCOPY & MICROBIOL,São Paulo,BRAZILWeb of Scienc