Determining the Cosmic Distance Scale from Interferometric Measurements of the Sunyaev-Zel'dovich Effect

We determine the distances to 18 galaxy clusters with redshifts ranging from z~0.14 to z~0.78 from a maximum likelihood joint analysis of 30 GHz interferometric Sunyaev-Zel'dovich effect (SZE) and X-ray observations. We model the intracluster medium (ICM) using a spherical isothermal beta model. We quantify the statistical and systematic uncertainties inherent to these direct distance measurements, and we determine constraints on the Hubble parameter for three different cosmologies. These distances imply a Hubble constant of 60 (+4, -4) (+13, -18) km s-1 Mpc-1 for an Omega_M = 0.3, Omega_Lambda = 0.7 cosmology, where the uncertainties correspond to statistical followed by systematic at 68% confidence. With a sample of 18 clusters, systematic uncertainties clearly dominate. The systematics are observationally approachable and will be addressed in the coming years through the current generation of X-ray satellites (Chandra & XMM-Newton) and radio observatories (OVRO, BIMA, & VLA). Analysis of high redshift clusters detected in future SZE and X-ray surveys will allow a determination of the geometry of the universe from SZE determined distances.Comment: ApJ Submitted; 40 pages, 9 figures (fig 3 B&W for size constraint), 13 tables, uses emulateapj5 styl

Analisi della risposta linfocitaria ad antigeni tubercolari nell'approccio diagnostico

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Problematiche diagnostiche nelle infezioni sostenute da Legionella pneumophila

The introduction of the research of Legionella antigen in urine has significantly speeded up the diagnosis of Legionella pneumophila infections but has decreased the number of respiratory samples submitted for coltural examination. In 2001 respiratory samples were submitted to our laboratory only from 7% of patients for which antigen detection in urine was requested. Such a percentage decreased to 4% in 2002 and to 2.5% in 2003. For 2 of 14 patients tested in 2002, legionellosis diagnosis could not be confirmed since urine antigen detection provided weak positive values and either respiratory samples for direct isolation of L. pneumophila or blood samples for specific serology tests were lacking.We believe that even if urine antigen detection test is a very useful quick test, it cannot be considered as the only diagnostic tool in Legionella spp. infections

Problematiche diagnostiche nelle infezioni sostenute da Legionella pneumophila

The introduction of the research of Legionella antigen in urine has significantly speeded up the diagnosis of Legionella pneumophila infections but has decreased the number of respiratory samples submitted for coltural examination. In 2001 respiratory samples were submitted to our laboratory only from 7% of patients for which antigen detection in urine was requested. Such a percentage decreased to 4% in 2002 and to 2.5% in 2003. For 2 of 14 patients tested in 2002, legionellosis diagnosis could not be confirmed since urine antigen detection provided weak positive values and either respiratory samples for direct isolation of L. pneumophila or blood samples for specific serology tests were lacking.We believe that even if urine antigen detection test is a very useful quick test, it cannot be considered as the only diagnostic tool in Legionella spp. infections

Molecular characterization of carbapenem-resistant Klebsiella pneumoniae ST14 and ST512 causing bloodstream infections in ICU and surgery wards of a tertiary university hospital of Verona (northern Italy): co-production of KPC-3, OXA-48, and CTX-M-15 \u3b2-lactamases

Klebsiella pneumoniae strain is an important opportunistic pathogen that causes severe nosocomial infections. In the present study a molecular characterization of carbapenem resistant K. pneumoniae, isolated from blood samples of hospitalized patients of Verona University Hospital, was performed. The simultaneous presence of SHV-1/CTX-M-15/KPC-3 and SHV-1/CTX-M-15/OXA-48 serin-\u3b2-lactamases was ascertained in the 89% and 11% of K. pneumoniae ST512 and K. pneumoniae ST14, respectively. Molecular characterization of bla genes showed that blaKPC-3 was found in Tn4401a transposon with the tnpR, tnpA, ISKpn6, and ISKpn7 mobile elements whereas blaCTX-M-15 was detected downstream ISEcp1 genetic element. A class 1 integron with a gene cassette of 780\u202fbp corresponding to aadA2 gene was identified in 33\u202fK. pneumoniae ST512 isolates

The Structure and Function of a Microbial Allantoin Racemase Reveal the Origin and Conservation of a Catalytic Mechanism

The S enantiomer of allantoin is an intermediate of purine degradation in several organisms and the final product of uricolysis in nonhominoid mammals. Bioinformatics indicated that proteins of the Asp/Glu racemase Superfamily could be responsible for the allantoin racemase (AllR) activity originally described in Pseudomonas species. In these proteins, a cysteine of the catalytic dyad is substituted with glycine, yet the recombinant enzyme displayed racemization activity with a similar efficiency (k(cat)/K-M approximate to 5 X 10(4) M-1 s(-1)) for the R and S enantiomers of allantoin. The protein crystal structure identified a glutamate residue located three residues downstream (E78) that can functionally replace the missing cysteine; the catalytic role of E78 was confirmed by site-directed mutagenesis. Allantoin can undergo racemization through formation of a bicyclic intermediate (faster) or proton exchange at the chiral center (slower). By monitoring the two alternative mechanisms by C-13 and H-1 nuclear magnetic resonance, we found that the velocity of the faster reaction is unaffected by the enzyme, whereas the velocity of the slower reaction is increased by 7 orders of magnitude. Protein phylogenies trace the origin of the racemization mechanism in enzymes acting on glutamate, a substrate for which proton exchange is the only viable reaction mechanism. This mechanism was inherited by allantoin racemase through divergent evolution and conserved in spite of the substitution of catalytic residues

Nocardia infection over 5 years (2011-2015) in an Italian tertiary care hospital

This study was conducted reviewing clinical records of 14 patients affected by nocardiosis over 5 years in a tertiary care hospital. Nocardia abscessus was responsible for one third of infections, deviating significantly from the results reported by other epidemiological investigations and highlighting the key role of molecular identification tests. Indeed, a precise identification of species is crucial for the determination of antibiotic sensitivity patterns and, consequently, for the choice of antibiotic treatment. Noteworthy, 40% of isolates of N. abscessus (formerly N. asteroides complex) showed resistance to carbapenems, which are usually recommended for empirical therapy

Whole-Genome Sequencing (WGS) of Carbapenem-Resistant K. pneumoniae Isolated in Long-Term Care Facilities in the Northern Italian Region

K. pneumoniae (KPN) is one of the widest spread bacteria in which combined resistance to several antimicrobial groups is frequent. The most common \u3b2-lactamases found in K. pneumoniae are class A carbapenemases, both chromosomal-encoded (i.e., NMCA, IMI-1) and plasmid-encoded (i.e., GES-enzymes, IMI-2), VIM, IMP, NDM, OXA-48, and extended-spectrum \u3b2-lactamases (ESBLs) such as CTX-M enzymes. In the present study, a total of 68 carbapenem-resistant KPN were collected from twelve long-term care facilities (LTCFs) in the Northern Italian region. The whole-genome sequencing (WGS) of each KPN strain was determined using a MiSeq Illumina sequencing platform and analysed by a bacterial analysis pipeline (BAP) tool. The WGS analysis showed the prevalence of ST307, ST512, and ST37 as major lineages diffused among the twelve LTCFs. The other lineages found were: ST11, ST16, ST35, ST253, ST273, ST321, ST416, ST1519, ST2623, and ST3227. The blaKPC-2, blaKPC-3, blaKPC-9, blaSHV-11, blaSHV-28, blaCTX-M-15, blaOXA-1, blaOXA-9, blaOXA-23, qnrS1, qnrB19, qnrB66, aac(6')-Ib-cr, and fosA were the resistance genes widespread in most LTCFs. In this study, we demonstrated the spreading of thirteen KPN lineages among the LTCFs. Additionally, KPC carbapenemases are the most widespread \u3b2-lactamase

Resistome and Virulome of Multi-Drug Resistant E. coli ST131 Isolated from Residents of Long-Term Care Facilities in the Northern Italian Region

: Long-term care facilities (LTCFs) are important reservoirs of antimicrobial-resistant (AMR) bacteria which colonize patients transferred from the hospital, or they may emerge in the facility as a result of mutation or gene transfer. In the present study, we characterized, from a molecular point of view, 43 E. coli strains collected from residents of LTCFs in Northern Italy. The most common lineage found was ST131, followed by sporadic presence of ST12, ST69, ST48, ST95, ST410 and ST1193. All strains were incubators of several virulence factors, with iss, sat, iha and senB being found in 84%, 72%, 63% and 51% of E. coli, respectively. Thirty of the ST131 analyzed were of the O25b:H4 serotype and H30 subclone. The ST131 isolates were found to be mainly associated with IncF plasmids, CTX-M-1, CTX-M-3, CTX-M-15, CTX-M-27 and gyrA/parC/parE mutations. Metallo-β-lactamases were not found in ST131, whereas KPC-3 carbapenemase was found only in two ST131 and one ST1193. In conclusion, we confirmed the spread of extended-spectrum β-lactamase genes in E. coli ST131 isolated from colonized residents living inside LTCFs. The ST131 represents an incubator of fluoroquinolones, aminoglycosides and other antibiotic resistance genes in addition to different virulence factors

Outbreak of Saprochaete clavata Sepsis in Hematology Patients: Combined Use of MALDI-TOF and Sequencing Strategy to Identify and Correlate the Episodes

New fungal species are increasingly reported in immunocompromised patients. Saprochaete clavata (S. clavata), an ascomycetous fungus formerly called Geotrichum clavatum, is intrinsically resistant to echinocandins and is often misidentified