Frontiers in microbiology
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Frontiers in microbiology · Jan 2016
Virulence of Cryptococcus sp. Biofilms In Vitro and In Vivo using Galleria mellonella as an Alternative Model.
Cryptococcus neoformans and C. gattii are fungal pathogens that are most commonly found in infections of the central nervous system, which cause life-threatening meningoencephalitis and can grow as a biofilm. Biofilms are structures conferring protection and resistance of microorganism to the antifungal drugs. This study compared the virulence of planktonic and biofilm cells of C. neoformans and C. gattii in Galleria mellonella model, as well as, the quantification of gene transcripts LAC1, URE1, and CAP59 by real time PCR. ⋯ C. neoformans and C. gattii cells in the biofilm forms were more virulent than the planktonic cells in G. mellonella. This suggests that the biofilm conditions may contribute to the virulence profile. Our results contribute to a better understanding of the agents of cryptococcosis in the host-yeast aspects of the interaction.
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Frontiers in microbiology · Jan 2016
Serotype 3 Remains the Leading Cause of Invasive Pneumococcal Disease in Adults in Portugal (2012-2014) Despite Continued Reductions in Other 13-Valent Conjugate Vaccine Serotypes.
Since 2010 the 13-valent pneumococcal conjugate vaccine (PCV13) replaced the 7-valent vaccine (PCV7) as the leading pneumococcal vaccine used in children through the private sector. Although, neither of the PCVs were used significantly in adults, changes in adult invasive pneumococcal disease (IPD) were expected due to herd protection. We characterized n = 1163 isolates recovered from IPD in adults in 2012-2014 with the goal of documenting possible changes in serotype prevalence and antimicrobial resistance. ⋯ Serotype 15A increased in 2012-2014 (0.7% to 3.5%, p = 0.011) and was strongly associated with antimicrobial resistance. However, the decreases in resistant isolates among serotypes 14 and 19A led to an overall decrease in penicillin non-susceptibility (from 17 to 13%, p = 0.174) and erythromycin resistance (from 19 to 13%, p = 0.034). Introduction of PCV13 in the NIP for children, as well as its availability for adults may further alter the serotypes causing IPD in adults in Portugal and lead to changes in the proportion of resistant isolates.
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Frontiers in microbiology · Jan 2016
High Prevalence of Gut Microbiota Colonization with Broad-Spectrum Cephalosporin Resistant Enterobacteriaceae in a Tunisian Intensive Care Unit.
Healthcare-associated infections due to cefotaxime-resistant (CTX-R) Enterobacteriaceae have become a major public health threat, especially in intensive care units (ICUs). Often acquired nosocomially, CTX-R Enterobacteriaceae can be introduced initially by patients at admission. This study aimed to determine the prevalence and genetic characteristics of CTX-R Enterobacteriaceae-intestinal carriage in ICU patients, to evaluate the rate of acquisition of these organisms during hospitalization, and to explore some of the associated risk factors for both carriage and acquisition. ⋯ Five colonized patients were infected by CTX-R Enterobacteriaceae (four with the same strain identified from their rectal swab and one with a different strain). Whether imported or acquired during the stay in the ICU, colonization by CTX-R Enterobacteriaceae is a major risk factor for the occurrence of serious nosocomial infections. Their systematic screening in fecal carriage is mandatory to prevent the spread of these multidrug resistant bacteria.