OXA-23 carbapenemase in multidrug-resistant Acinetobacter baumannii ST2 type: first identification in L'Aquila Hospital (Italy).

In this study 114 extensively drug-resistant Acinetobacter baumannii clinical isolates were characterized. The strains were collected at L'Aquila Hospital after the earthquake in L'Aquila city (central Italy) on the 6th of April 2009. The genes blaOXA-23 and blaOXA-51 were detected in all clinical isolates analyzed, whereas blaTEM-1 allele was detected in 56/114 isolates. The blaOXA-23 gene is located downstream the ISAba region and is under control of a strong promoter. On 42/80 A. baumannii the presence of two class 1 integrons was ascertained on chromosomal DNA. Variable regions show different gene array: (1) aadB and aadA2, (2) aacA4, aac(6')-Ib-cr, and aadA1. Macrorestriction analysis using ApaI restriction endonuclease identifies three clusters (A, B, and C) according to pulsed-field gel electrophoresis profiles. All isolates analyzed belong to the clone A. baumannii sequence type 2.

Molecular typing of Salmonella enterica subspecies enterica serovar Typhimurium isolated in Abruzzo region (Italy) from 2008 to 2010.

In this study, 47 antibiotic-resistant strains of Salmonella enterica subspecies enterica serovar Typhimurium (ST) were characterised, including 15 monophasic variants 1, 4, [5], 12:i:-, (STm) isolated from different matrices. They were all selected from 389 Salmonella enterica subspecies enterica strains isolated during 2008-2010 in Abruzzo region (Italy). Thirty-seven strains showed to be resistant to more than 1 antibiotic. Among 47 isolates, phage type U311 and DT104 were identified. The ASSuT resistance pattern was predominant in mST strains and ACSSuT in ST DT104 and U302. A multiplex Polimerase Chain Reaction (PCR) method was used to investigate 4 genes: fluorfenicol (floSt), virulence (spvC), invasine (invA) and integrase (int). All ST the strain were positive for invA gene and 28,32% of strains were positive for spvC gene. PFGE analysis revealed a large number of small clonal populations, however not ascrivable to outbreaks.

Emergence of blaKPC-3-Tn4401a in Klebsiella pneumoniae ST512 in the municipal wastewater treatment plant and in the university hospital of a town in central Italy.

In this study, 20 carbapenem-resistant environmental Klebsiella pneumoniae strains were found to correlate with 18 clinical K. pneumoniae isolates from the teaching hospital of L'Aquila city, Italy. All strains analysed by multilocus sequence typing (MLST) were included in the same clone (ST512), and pulsed-field gel electrophoresis demonstrated a genetic relationship between the clinical isolates and most environmental strains. Both environmental and clinical strains harboured the same mobile genetic elements: transposon Tn4401a including a blaKPC-3 determinant; and a class 1 integron with the gene cassette aadA2.

Expression analysis of the gene encoding for the U-box-type ubiquitin ligase UBE4A in human tissues.

The Ubiquitination Factor E4A gene (UBE4A) encodes for a U-box-type ubiquitin ligase, originally described as an E4 ubiquitination factor. UBE4A is a mammalian homolog of Saccharomyces cerevisiae Ufd2. The UBE4A gene has been mapped on the human chromosome region 11q23.3, a critical region involved in some specific cancers such as neuroblastoma. Northern blots analysis on foetal and adult human tissues revealed a single band of approximately 7.5 kb transcript most abundant in the heart, skeletal muscle and kidney. We generated a polyclonal antibody to UBE4A and performed immunoblot and immunohistochemical analysis. The UBE4A protein appeared as a single band of approximately 125 kDa. UBE4A was present in the skeletal muscle, kidney and liver; a faint band was visible in peripheral blood leukocytes and spleen. We did not reveal expression of UBE4A in whole brain, colon, lung and heart. At the cellular level, UBE4A results predominantly expressed in the nucleus and the cytoplasm of cortical neurons and liver and in the nucleus of tubular kidney cells. In the liver, the nucleus of similar cells appeared to be unstained or stained at different levels suggesting that UBE4A may have a cell cycle dependent expression or a role of in cell cycle control. In conclusion, our results show that UBE4A is expressed in different tissues in a pattern that seems to be dependent from cell type and cell cycle and that UBE4A might have a specific role in different biochemical processes other than ubiquitination, including growth or differentiation.

Catheter-related candidemia caused by Candida lipolytica in a patient receiving allogeneic bone marrow transplantation.

Candida lipolytica was recovered from the blood and the central venous catheter in a patient receiving allogeneic bone marrow transplantation. Two C. lipolytica strains from different geographical areas and the ATCC 9773 strain of C. lipolytica were used as controls. C. lipolytica was identified by standard methods. MICs indicated antifungal susceptibilities to amphotericin B, fluconazole, and itraconazole for all strains. In vitro testing and scanning electron microscopy showed that C. lipolytica was capable of producing large amounts of viscid slime material in glucose-containing solution, likely responsible for the ability of the yeast to adhere to catheter surfaces. Restriction fragment length polymorphisms revealed an identical profile for all clinical isolates, unrelated to those observed for the control strains. This finding suggested the absence of microevolutionary changes in the population of the infecting strain, despite the length of the sepsis and the potential selective pressure of amphotericin B, which had been administered to the patient for about 20 days. The genomic differences that emerged between the isolates and the control strains were indicative of a certain degree of genetic diversity between C. lipolytica isolates from different geographical areas.

Single primer pair for PCR identification of Candida parapsilosis group I isolates.

A DNA fragment, isolated from a genomic DNA mini-library of Candida parapsilosis group I reference strain ATCC 22019, was sequenced and characterised. The fragment was first probed by Southern blotting against a pool of DNA from several yeasts. The hybridisation tests revealed that the probe was specific for strain ATCC 22019 and 49 (90.74%) of 54 C. parapsilosis clinical and soil isolates that were attributed to C. parapsilosis group I by the electrophoretic images of their restriction fragment length polymorphisms (RFLPs) and electrophoretic karyotype (EK). The remaining five negative isolates, according to the same criteria, were attributed to group II (one isolate) and III (four isolates). Two primers were selected from the probe DNA sequence and a PCR-based test was developed for specifically detecting C. parapsilosis group I isolates, which represent the majority of the common clinical isolates. The PCR assay confirmed the Southern hybridisation results. This PCR assay could be a simple and reproducible tool for the rapid, sensitive and species-specific identification of C. parapsilosis major group I isolates.