Evolution of macrolide resistance in streptococcus pyogenes over 14 years in an area of central Italy

We evaluated temporal fluctuations in macrolide resistance rates, analysing genetic determinants of resistance and clonal evolution in a population of 2744 S. pyogenes isolates collected in the period 2000–2013. The total resistance rate to erythromycin of the isolates was 17.9%. A maximum of erythromycin resistance emerged in 2000 (38.6%), followed by a significant decrease to 5.2% in 2012 (P<0.0001). Molecular analysis revealed the presence and co-presence of known genetic resistance determinants mefA, mefE, ermTR and ermB, in line with phenotypes. PFGE analysis identified genetically related groups in 2000 and 2007–2008, mainly the MLS and M phenotypes, respectively. The most prevalent emm types among a representative subset of resistant isolates were emm2, emm75 and emm77. All emm2 and 88.2% of the strains harbouring the emm75 gene were only recorded in M-phenotype strains, whilst all emm77-positive strains had the inducible MLS phenotype. The analysed susceptible isolates showed several emm types partially shared with resistant ones. Our results suggest that changes in bacterial population clonality, rather than horizontal transfer of resistance determinants, plays a major epidemiological role in S. pyogenes. Continuous monitoring of microbiological epidemiology seems to be crucial for correct and effective management of streptococcal infections

Effects of leucine supplementation and resistance exercise on dexamethasone-induced muscle atrophy and insulin resistance in rats

Objective: We aimed to evaluate the effects of resistance exercise (RE) and leucine (LEU) supplementation on dexamethasone (DEXA)-induced muscle atrophy and insulin resistance.Methods: Male Wistar rats were randomly divided into DEXA(DEX), DEXA + RE (DEX-RE), DEXA + LEU (DEX-LEU), and DEXA + RE + LEU (DEX-RE-LEU) groups. Each group received DEXA 5 mg . kg(-1) . d(-1) for 7 d from drinking water and were pair-fed to the DEX group; LEU-supplemented groups received 0.135 g . kg(-1) . d(-1) through gavage for 7 d; the RE protocol was based on three sessions of squat-type exercise composed by three sets of 10 repetitions at 70% of maximal voluntary strength capacity.Results: the plantaris mass was significantly greater in both trained groups compared with the non-trained groups. Muscle cross-sectional area and fiber areas did not differ between groups. Both trained groups displayed significant increases in the number of intermediated fibers (IIa/IIx), a decreased number of fast-twitch fibers (IIb), an increased ratio of the proteins phospho(Ser2448)/ total mammalian target of rapamycin and phospho(Thr389)/total 70-kDa ribosomal protein S6 kinase. and a decreased ratio of phospho(Ser253)/total Forkhead box protein-3a. Plasma glucose was significantly increased in the DEX-LEU group compared with the DEX group and RE significantly decreased hyperglycemia. the DEX-LEU group displayed decreased glucose transporter-4 translocation compared with the DEX group and RE restored this response. LEU supplementation worsened insulin sensitivity and did not attenuate muscle wasting in rats treated with DEXA. Conversely, RE modulated glucose homeostasis and fiber type transition in the plantaris muscle.Conclusion: Resistance exercise but not LEU supplementation promoted fiber type transition and improved glucose homeostasis in DEXA-treated rats. (C) 2012 Elsevier Inc. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ São Paulo, Lab Appl Nutr & Metab, Sch Phys Educ & Sports, São Paulo, BrazilUniv São Paulo, Inst Biomed Sci, São Paulo, BrazilUniv São Paulo, Lab Mol & Cellular Physiol Exercise, Sch Phys Educ & Sports, São Paulo, BrazilUniv São Paulo, Sch Med, Lab Expt Hypertens, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biosci, São Paulo, BrazilClermont Univ, UFR Med, UMR Nutr Humaine 1019, Clermont Ferrand, FranceINRA, UMR Unite Nutr Humaine 1019, F-63122 St Genes Champanelle, FranceUniversidade Federal de São Paulo, Dept Biosci, São Paulo, BrazilFAPESP: 08/51090-1FAPESP: 10/07062-3FAPESP: 10/10852-6FAPESP: 11/04690-6Web of Scienc

Pneumococcal disease in a paediatric population in a hospital of central Italy: a clinical and microbiological case series from 1992 to 2006

7noreservedOBJECTIVES: Streptococcus pneumoniae is frequently isolated from carrier children, but it also causes localized and invasive diseases. Increasing incidence of chemoresistance can affect the efficacy of empiric therapy and it motivates interest in primary prophylaxis. The study aims to investigate clinical and microbiological features of paediatric pneumococcal infections in an Italian province. METHODS: Retrospective clinical analysis of 640 children, hospitalized from 1992 to 2006 with one culture positive for S. pneumoniae, was performed. Chemosusceptibility tests and serotyping were carried out on isolates; statistical analysis was applied to compare variables. RESULTS: Overall, 47.8% were carriers, 49% and 3.2% had, respectively, a localized or invasive disease; S. pneumoniae aetiology accounted for 25% of meningitis and 16% of sepsis. On the total isolates, 10.2% were penicillin non-susceptible, 35.15% were erythromycin resistant, with increasing rates over years. Prevalent invasive serotypes were 1 (38.1%) and 7F (9.5%). CONCLUSIONS: The study sustains pneumococcal disease relevance in children, on the strength of a 15 year observation. Long time period can represent a limit due to population characteristics changing; a selection bias could also be present due to hospitalized only patient analysis. However, we documented variable evolution of chemoresistance and a peculiar serotype spreading, offering microbiological basis for an appropriate clinical approach.mixedF. MONTAGNANI; FANETTI A; STOLZUOLI L; CROCI L; ARENA F; ZANCHI A; CELLESI CMontagnani, Francesca; Fanetti, Alessandra; Stolzuoli, Lucia; Croci, Leonardo; Arena, Fabio; Zanchi, Alessandra; Cellesi, Carl

Microbiological features of acute bacterial conjunctivitis in a central Italian area

The study aims to identify bacteria causing conjunctivitis in a central Italian area and to analyze chemosusceptibility. From 2005 to 2006, 91 conjunctival swabs were collected from acute conjunctivitis cases and screened for common bacteria and fungi. Susceptibility tests were performed on isolates. Staphylococcus aureus, Streptococcus pneumoniae and Haemophilus influenzae amounted to 86.2%. Overall, 100% of strains were susceptible to chloramphenicol and 96.6% to quinolones. Conversely, 20.7% of isolates were tetracycline-resistant and, even if all Gram negative isolates were susceptible to gentamicin, the most frequently isolated pneumococci are constitutively resistant. The study provides support for a rational choice of empiric therapy