New V. cholerae atypical El Tor variant emerged during the 2006 epidemic outbreak in Angola

<p>Abstract</p> <p>Background</p> <p><it>V. cholerae </it>is the etiological agent of cholera, a major public health concern in most developing countries. Virulence of <it>V. cholerae </it>relies on the powerful cholera toxin, encoded by the CTX prophage. The emergence of new pathogenic variants in the recent years has been mostly associated with new CTX prophage rearrangements.</p> <p>Results</p> <p>In this retrospective study, we show that the epidemic <it>V. cholerae </it>O1 El Tor strain responsible for the 2006 outbreak in Angola is clonally and genetically different from El Tor strains circulating in the 1990s in the same area. Strains from 2006 carry ICE<it>Vch</it>Ang3 of the SXT/R391 family. This ICE is associated with a narrower multidrug resistance profile compared to the one conferred by plasmid p3iANG to strains of the 1990s. The CTX prophage carried by 2006 El Tor strains is characterized by <it>rstR^ET</it>and <it>ctxB^Cla</it>alleles organized in a RS1-RS2-Core array on chromosome I. Interestingly, the newly emerging atypical strain belongs to a clade previously known to comprise only clinical isolates from the Indian subcontinent that also contain the same ICE of the SXT/R391 family.</p> <p>Conclusions</p> <p>Our findings remark the appearance of a novel <it>V. cholerae </it>epidemic variant in Africa with a new CTXΦ arrangement previously described only in the Indian Subcontinent.</p

New <i>V. cholerae</i> atypical El Tor variant emerged during the 2006 epidemic outbreak in Angola

Background V. cholerae is the etiological agent of cholera, a major public health concern in most developing countries. Virulence of V. cholerae relies on the powerful cholera toxin, encoded by the CTX prophage. The emergence of new pathogenic variants in the recent years has been mostly associated with new CTX prophage rearrangements. Results In this retrospective study, we show that the epidemic V. cholerae O1 El Tor strain responsible for the 2006 outbreak in Angola is clonally and genetically different from El Tor strains circulating in the 1990s in the same area. Strains from 2006 carry ICEVchAng3 of the SXT/R391 family. This ICE is associated with a narrower multidrug resistance profile compared to the one conferred by plasmid p3iANG to strains of the 1990s. The CTX prophage carried by 2006 El Tor strains is characterized by rstRET and ctxBCla alleles organized in a RS1-RS2-Core array on chromosome I. Interestingly, the newly emerging atypical strain belongs to a clade previously known to comprise only clinical isolates from the Indian subcontinent that also contain the same ICE of the SXT/R391 family. Conclusions Our findings remark the appearance of a novel V. cholerae epidemic variant in Africa with a new CTXΦ arrangement previously described only in the Indian Subcontinent.</br

Genomic analysis of Sardinian 26544/OG10 isolate of African swine fever virus

Abstract Comparative genomic analysis aims to underscore genetic assortment diversification in distinct viral isolates, to identify deletions and to carry out evolutionary studies. We sequenced the first complete genome of an ASFV p72 genotype I strain isolated from domestic pigs in Sardinia (Italy) using Next-Generation Sequence (NGS) technology. The genome is 182,906 bp long, contains 164 ORFs and has a 99.20% nucleotide identity to the L60 strain. Comparison analysis against the 16 ASFV genomes available in the database showed that 136 ORFs are present in nine ASFV isolates annotated to date. The most divergent ORFs codify for uncharacterized proteins such as X69R and DP96R, which have 51.3% and 70.4% nucleotide identity to the other isolates. A comparison between the Sardinian isolate and the avirulent isolates OURT 88/3, NHV, BA71V was also carried out. Major variations were found within the multigene families (MGFs) located in the left and right genome regions

Investigation of rpoS and dps genes in sodium hypochlorite resistance of Salmonella Enteritidis SE86 isolated from foodborne illness outbreaks in southern Brazil.

In Rio Grande do Sul, southern Brazil, Salmonella Enteritidis is one of the principal microorganisms responsible for foodborne disease. The present study was conducted to compare the sodium hypochlorite resistance of Salmonella Enteritidis SE86 with that of other strains of Salmonella Enteritidis isolated from different regions of the world and to investigate the involvement of the rpoS and dps genes in resistance to this disinfectant. We tested five Salmonella Enteritidis wild-type (WT) strains isolated from different countries, two mutant strains of Salmonella Enteritidis SE86, and two tagged (3XFLAG) strains of Salmonella Enteritidis SE86 for their resistance to sodium hypochlorite (200 ppm). The survival of the WT and attenuated strains was determined based on bacterial counts, and tagged proteins (Dps and RpoS) were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with anti-FLAG antibodies. None of the WT strains of Salmonella Enteritidis were totally inactivated after 20 min. The SE86 strain lacking dps was more sensitive to sodium hypochlorite than was the WT SE86 strain, with a 2-log reduction in counts after 1 min. The RpoS and Dps proteins were actively expressed under the conditions tested, indicating that in Salmonella Enteritidis SE86 these genes, which are expressed when in contact with sodium hypochlorite, are related to oxidative stress

Incendi ed ecosistemi mediterranei: valutazione degli impatti in regime di cambiamento climatico

In Europa, in particolare nella parte meridionale, ogni anno si registrano mediamente 60.000 incendi, con una superficie complessiva percorsa dal fuoco di circa 600.000 ettari. Negli ultimi anni si è sviluppato un interessante dibattito sui fattori che guidano il regime degli incendi in queste aree. Le ricerche più recenti, supportate dalla statistica, confermano il ruolo guida del clima e della meteorologia, strettamente condizionato dall’uso del suolo e con diverse caratteristiche a seconda della regione. In condizioni di cambiamenti climatici e socioeconomici, quali quelle attuali, è logico pensare che anche il regime degli incendi subisca importanti influenze, a seguito delle modifiche del clima e dell’uso del suolo

Analyzing the recent dynamics of wildland fires in Quercus suber L. woodlands in Sardinia (Italy), Corsica (France) and Catalonia (Spain)

Wildland fires represent a major threat to Quercus suber L. ecosystems, which provide relevant socioeconomic and ecological services in the Mediterranean Basin. In this work, we analyzed recent wildland fire dynamics in cork oak woodlands along the fire-prone areas of Sardinia (Italy), Corsica (France) and Catalonia (Spain). We first characterized geographic extent and main characteristics of cork oak woodlands in these regions and analyzed how environmental (climate and elevation) and socioeconomic factors (population and land uses) vary in the areas covered by Quercus suber L. We then evaluated how wildfires affected cork oak stands and, by logistic regression analysis, to what extent wildfires in cork oak areas were related to the above set of environmental and anthropic explanatory variables. Results revealed specific variations across study areas in cork oak characteristics as well as in environmental and social factors. We highlighted the spatial and temporal patterns of wildfires on cork oak woodlands, in terms of extent, seasonality, frequency and main driving factors. In the period 2003–2015, the percentage of cork oak woodlands burned ranged from 3.42% in Corsica to 11.30% in Sardinia. A few large and severe wildfires accounted for most of the area burned in cork oak woodlands. The most significant predictive variable that explained the spatial variation in wildland fire ignitions inside or nearby cork oaks was summer precipitation, while the weight of other factors varied depending on the region. This study provides evidence on recent fire dynamics in cork oak woodlands and gives valuable information and insights for the implementation of forest management and planning strategies in the Mediterranean area.This work was supported by the Sardinia Region under the project “Multifunzionalità delle foreste a quercia da sughero in Sardegna” (Multifunctionality of cork oak forests in Sardinia) funded within L.R. n. 7/2007 “Promozione della ricerca scientifica e della innovazione tecnologica in Sardegna,/Tender no. 2″, and by the “Proterina-2” Project funded by the Italia Francia-Marittimo Programme

Recent dynamics of forest fires in <i>Quercus suber</i> stands in Sardinia, Corsica and Catalonia

In this study, we analyzed the recent dynamics of forest fires in Quercus suber stands in Sardinia (Italy), Corsica (France), and Catalonia (Spain) for the period 2003-2015