Developmental neuroscience research has not yet fully unveiled the dynamics involved in human birth. The trigger of the first breath, often assumed to be the marker of human life, has not been characterized nor has the process entailing brain modification and activation at birth been clarified yet. To date, few researchers only have investigated the impact of the extrauterine environment, with its strong stimuli, on birth. This 'hypothesis and theory' article assumes the role of a specific stimulus activating the central nervous system (CNS) at human birth. This stimulus must have specific features though, such as novelty, efficacy, ubiquity, and immediacy. We propose light as a robust candidate for the CNS activation via the retina. Available data on fetal and neonatal neurodevelopment, in particular with reference to retinal light-responsive pathways, will be examined together with the GABA functional switch, and the subplate disappearance, which, at an experimental level, differentiate the neonatal brain from the fetal brain. In this study, we assume how a very rapid activation of retinal photoreceptors at birth initiates a sudden brain shift from the prenatal pattern of functions to the neonatal setup. Our assumption implies the presence of a photoreceptor capable of capturing and transducing light/photon stimulus, transforming it into an effective signal for the activation of new brain functions at birth. Opsin photoreception or, more specifically, melanopsin-dependent photoreception, which is provided by intrinsically photosensitive retinal ganglion cells (ipRGCs), is considered as a valid candidate. Although what is assumed herein cannot be verified in humans based on knowledge available so far, proposing an important and novel function can trigger a broad range of diversified research in different domains, from neurophysiology to neurology and psychiatry.

Autochthonous hepatitis E virus (HEV) is an emerging health issue in developed countries and is thought to be a porcine zoonosis; its spread is underestimated and there is concern about the possibility of chronic infection in immunosuppressed patients; HEV transmission through blood has also been demonstrated. We conducted a retrospective study (2007-2013) on HEV seroprevalence using stored serum samples from 132 blood donors and 118 renal transplant recipients living mainly in central Italy. Anti-HEV IgG was positive in 12/132 (9.1%) of the blood donors and 12/118 (10.2%) of the transplant recipients. All subjects but one were autochthonous and none showed signs of liver disease at the time of sampling. A significant association was documented between mean age of patients and the serology against HEV especially in the group of blood donors. Our study, albeit limited and retrospective, confirms the circulation of autochthonous HEV in central Italy; the presence of antibodies against HEV in particular categories of persons such as blood donors and transplant patients, who are not screened for the infection, raises questions in terms of transfusion safety and health protection of immunocompromised patients.

Human Cytomegalovirus (HCMV) represents the most common viral complication affecting solid organ transplant recipients (SOTRs) and its management is still debated. This study analyzes the association between HCMV infection and renal transplant recipients' outcomes. From January 2008 through December 2009, 97 consecutive renal transplant recipients were retrospectively studied. HCMV disease prevention was pursued by pre-emptive therapy, reserving long-term prophylaxis for high-risk patients. A total of 32/97 patients (32.9%) developed HCMV positivity in blood for a cumulative estimated proportion at 3 months post-transplantation of 0.21. HCMV disease developed in 7 patients (7.2%), while 25 patients had asymptomatic infection (25.7%). No patient died from HCMV. HCMV disease, older graft age and post-transplant renal dysfunction were independent predictors of rejection while HCMV infection without disease was associated with a higher number of other complications. The use of basiliximab was independently associated with a reduced hazard of HCMV infection/ disease. In renal transplant recipients HCMV infection still represents a major issue influencing the outcome, not only because of the potential to develop the disease and its link to graft rejection, but also in terms of higher number of complications. The choice of different immunosuppressive strategies might be associated with HCMV replication.

Multidrug-resistant isolates of a clonal lineage of Pseudomonas aeruginosa producing the VIM-2 metallo-beta-lactamase (MBL), involved in a large outbreak in an Italian hospital, were compared with MBL-negative strains that had caused outbreaks in two French hospitals. Although the isolates had different carbapenem MICs, the VIM-2-producing isolates from Italy carried identical, or very similar, allelic forms of the oprD gene, harboured a common class 1 integron, belonged to the same multilocus sequence type (ST111), and showed macrorestriction profiles that were related to those of the MBL-negative French strains. These results support the concept of independent acquisition of resistance determinants by members of a widespread clonal lineage of P. aeruginosa.

ABSTRACT An outbreak of multidrug-resistant Pseudomonas aeruginosa strains producing VIM-type metallo-β-lactamases (MBLs) has occurred in an Italian hospital since 2000 (C. Lagatolla, E. A. Tonin, C. Monti-Bragadin, L. Dolzani, F. Gombac, C. Bearzi, E. Edalucci, F. Gionechetti, and G. M. Rossolini, Emerg. Infect. Dis. 10:535-538, 2004). In this work, using molecular methods, we characterized 128 carbapenem-resistant isolates (including 98 VIM-positive isolates) collected from that hospital from 2000 to 2002 to investigate the dynamics of the dissemination of MBL producers in the clinical setting. Genotyping by random amplification of polymorphic DNA and pulsed-field gel electrophoresis showed that most VIM-positive isolates belonged to two different clonal lineages, producing either a VIM-1- or a VIM-2-like MBL, whose ancestors were detected for the first time in the hospital in 1999, suggesting that clonal expansion played a predominant role in the dissemination of these isolates. The 86 clonally related isolates carrying a bla VIM-1 -like gene on an In70-like integron were clearly related to a VIM-1-positive P. aeruginosa clone circulating in various Italian hospitals since the late 1990s. VIM-negative P. aeruginosa strains related to the VIM-1-positive clone were detected during the same period, suggesting that the latter strain was derived from a clonal lineage already circulating in the hospital. In the VIM-2-like positive clone, the MBL gene was carried by an unusual class 1 integron, named In71, lacking the 3′ conserved sequence region typical of sul1 -associated integrons. A different class 1 integron with an original structure carrying a bla VIM-2 determinant, named In74, was detected in a sporadic isolate. A retrospective investigation did not reveal the presence of strains related to any of the VIM-producing isolates earlier than 1997.

ABSTRACTA novel OXA-type enzyme, named OXA-46, was found to be encoded by a gene cassette inserted into a class 1 integron from a multidrug-resistantPseudomonas aeruginosaclinical isolate. The variable region of the integron also contained ablaVIM-1metallo-β-lactamase cassette and a duplicatedaacA4aminoglycoside acetyltransferase cassette. OXA-46 belongs to the OXA-2 lineage of class D β-lactamases. It exhibits 78% sequence identity with OXA-2 and the highest similarity (around 92% identity) with another OXA-type enzyme detected in clinical isolates ofBurkholderia cepaciaand in unidentified bacteria from a wastewater plant. Expression ofblaOXA-46inEscherichia colidecreased susceptibility to penicillins and narrow-spectrum cephalosporins but not to extended-spectrum cephalosporins, cefsulodin, aztreonam, or carbapenems. The enzyme was overproduced inE. coliand purified by two anion-exchange chromatography steps (approximate yield, 6 mg/liter). OXA-46 was made of a 28.5-kDa polypeptide and exhibited an alkaline pI (7.8). In its native form OXA-46 appeared to be dimeric, and the oligomerization state was not affected by EDTA. Kinetic analysis of OXA-46 revealed a specificity for narrow-spectrum substrates, including oxacillin, other penicillins (but not temocillin), and narrow-spectrum cephalosporins. The enzyme apparently did not interact with temocillin, oxyimino-cephalosporins, or aztreonam. OXA-46 was inactivated by tazobactam and carbapenems and, although less efficiently, also by clavulanic acid. Enzyme activity was not affected either by EDTA or by divalent cations and exhibited low susceptibility to NaCl. These findings underscore the functional and structural diversity that can be encountered among class D β-lactamases.

ABSTRACT Three epidemiologically independent Pseudomonas aeruginosa isolates, representative of the first VIM-1 metallo-β-lactamase producers detected at three different hospitals in northern Italy, were investigated to determine their genomic relatedness and to compare the structures of the genetic supports for the VIM-1 determinants. The three isolates, all of serotype O11, appeared to be clonally related according to the results of genotyping by macrorestriction analysis of genomic DNA by pulsed-field gel electrophoresis and random amplification of polymorphic DNA. Investigation of the genetic support for the bla VIM-1 determinant revealed that it was carried on identical or almost identical integrons (named In70.2 and In70.3) located within a conserved genomic context. The integrons were structurally related to In70 and In110, two plasmid-borne bla VIM-1 -containing integrons from Achromobacter xylosoxidans and Pseudomonas putida isolates, respectively, from the same geographic area (northern Italy) and were found to be inserted close to the res site of a Tn 5051 -like transposon, different from any of those described previously, that was apparently carried on the bacterial chromosome. The present findings suggest that the three VIM-1-producing isolates are members of the same clonal complex which have been spreading in hospitals in northern Italy since the late 1990s and point to a common ancestry of their bla VIM-1 -containing integrons.

Three epidemiologically independent Pseudomonas aeruginosa isolates, representative of the first VIM-1 metallo-beta-lactamase producers detected at three different hospitals in northern Italy, were investigated to determine their genomic relatedness and to compare the structures of the genetic supports for the VIM-1 determinants. The three isolates, all of serotype O11, appeared to be clonally related according to the results of genotyping by macrorestriction analysis of genomic DNA by pulsed-field gel electrophoresis and random amplification of polymorphic DNA. Investigation of the genetic support for the bla(VIM-1) determinant revealed that it was carried on identical or almost identical integrons (named In70.2 and In70.3) located within a conserved genomic context. The integrons were structurally related to In70 and In110, two plasmid-borne bla(VIM-1)-containing integrons from Achromobacter xylosoxidans and Pseudomonas putida isolates, respectively, from the same geographic area (northern Italy) and were found to be inserted close to the res site of a Tn5051-like transposon, different from any of those described previously, that was apparently carried on the bacterial chromosome. The present findings suggest that the three VIM-1-producing isolates are members of the same clonal complex which have been spreading in hospitals in northern Italy since the late 1990s and point to a common ancestry of their bla(VIM-1)-containing integrons.

A Pseudomonas putida strain showing broad-spectrum resistance to beta-lactams, including expanded-spectrum cephalosporins and carbapenems, was isolated from a patient with a urinary tract infection at the University Hospital of Varese in northern Italy. The isolate was found to produce metallo-beta-lactamase activity and to harbor a 50-kb plasmid, named pVA758, carrying a new bla(IMP) determinant, named bla(IMP-12). Plasmid pVA758 was not self-transferable by conjugation to either Escherichia coli or Pseudomonas aeruginosa but could be introduced by electroporation and maintained in the latter host, where it conferred resistance or decreased susceptibility to various beta-lactams. The IMP-12 enzyme is quite divergent from other IMP variants: its closest relatives are IMP-8 and IMP-2 (89 and 88% sequence identity, respectively), and IMP-1 is 85% identical to IMP-12. The bla(IMP-12) determinant is carried on an integron-borne gene cassette whose attC recombination site is related to those present in cassettes containing bla(IMP-1), bla(IMP-6), bla(IMP-7), bla(IMP-10), and bla(IMP-11) and unrelated to that present in cassettes containing bla(IMP-2) and bla(IMP-8). IMP-12 was overproduced in E. coli by using a T7-based expression system and was purified by cation-exchange chromatography followed by gel filtration. Kinetic analysis revealed that, like other IMP variants, IMP-12 exhibits an overall preference for cephalosporins and carbapenems rather than for penicillins and does not hydrolyze temocillin and aztreonam. However, IMP-12 also exhibits some notable functional differences from other IMP variants, including uniformly poor activity toward penicillins (k(cat)/K(m) values, around 10(4) M(-1). s(-1)) and a remarkably high K(m) (around 900 micro M) for imipenem.

ABSTRACT A novel gene, aac ( 3 )- Ic , encoding an AAC(3)-I aminoglycoside 3- N -acetyltransferase, was identified on a gene cassette inserted into a Pseudomonas aeruginosa integron that also carries a bla VIM-2 and a cmlA7 gene cassette. The aac ( 3 )- Ic gene product is 59 and 57% identical to AAC(3)-Ia and AAC(3)-Ib, respectively, and confers resistance to gentamicin and sisomicin.

ABSTRACT Integron carriage by 36 epidemiologically unrelated Acinetobacter baumannii isolates collected over an 11-year period from patients in six different Italian hospitals was investigated. Sixteen type 1 integron-positive isolates (44%) were found, 13 of which carried the same array of cassettes, i.e., aacC1 , orfX, orfX′, and aadA1a. As ribotype analysis of the isolates demonstrated a notable genetic diversity, horizontal transfer of the entire integron structure or ancient acquisition was hypothesized.

ABSTRACT Successful carbapenem-based chemotherapy for the treatment of Pseudomonas infections has been seriously hindered by the recent appearance of IMP- and VIM-type metallo-β-lactamases, which confer high-level resistance to carbapenems and most other β-lactams. Recently, multidrug-resistant Pseudomonas putida isolates for which carbapenem MICs were ≥32 μg/ml were recovered from cultures of urine from three inpatients in the general intensive care unit of the Ospedale di Circolo, Varese, Italy. Enzyme assays revealed production of a metallo-β-lactamase activity, while molecular analysis detected in each isolate a blaVIM-1 determinant carried by an apparently identical medium-sized plasmid. Conjugation experiments were unsuccessful in transferring the β-lactamase determinant to Escherichia coli or Pseudomonas aeruginosa. Macrorestriction analysis by pulsed-field gel electrophoresis demonstrated that the isolates were of clonal origin. PCR mapping and sequencing of the variable region of the plasmid-borne class 1 integron carrying the blaVIM-1 determinant (named In110) showed that the blaVIM-1-containing cassette was identical to that previously found in strains of different species from other Italian hospitals and that the cassette array of In110 was not identical but clearly related to that of In70 (a blaVIM-1-containing plasmid-borne integron from an Achromobacter xylosoxidans isolate), pointing to a common origin of this cassette and to a related evolutionary history of their cognate integrons.

A blaVIM-2 metallo-β-lactamase determinant, identical to that previously identified in Pseudomonas aeruginosa COL-1 isolate from a French hospital, was detected on a 28-kb plasmid carried by a nosocomial isolate of P. aeruginosa from Verona, Italy. In this plasmid the blaVIM-2 determinant was inserted into a class 1 integron of original structure, named In72, that contains a partially deleted intI1 integrase gene and two gene cassettes. The first cassette carries an aacA4 aminoglycoside acetyl transferase determinant. The second cassette carries a blaVIM-2 determinant followed by a partially deleted attC site. The structure of In72 was notably different from that of In56, the blaVIM-2-containing integron found in the COL-1 isolate, revealing the existence of molecular heterogeneity among blaVIM-2-containing integrons in clinical isolates of P. aeruginosa from Europe.

An Achromobacter xylosoxydans strain showing broad-spectrum resistance to beta -lactams (including carbapenems) and aminoglycosides was isolated at the University Hospital of Verona (Verona, Italy), This strain was found to produce metallo-beta -lactamase activity and to harbor a 30-kb nonconjugative plasmid, named pAX22, carrying a bla(VIM-1) determinant inserted into a class 1 integron, Characterization of this integron, named In70, revealed an original array of four gene cassettes containing, respectively, the bla(vim-1) gene and three different aminoglycoside resistance determinants, including an aacA4 allele, a new aph-like gene named aphA15, and an aadA1 allele, The aphA15 gene is the first example of an aph-like gene carried on a mobile gene cassette, and its product exhibits close similarity to the APH(3')-IIa aminoglycoside phosphotransferase encoded by Tn5 (36% amino acid identity) and to an APH(3')-IIb enzyme from Pseudomonas aeruginosa (38% amino acid identity). Expression of the cloned aphA15 gene in Escherichia coli reduced the susceptibility to kanamycin and neomycin as well as (slightly) to amikacin, netilmicin, and streptomycin, Characterization of the 5' and 3' conserved segments of In70 and of their flanking regions showed that In70 belongs to the group of class 1 integrons associated with defective transposon derivatives originating from Tn402-like elements. The structure of the 3' conserved segment indicates the closest ancestry with members of the In0-In2 lineage. In70, with its array of cassette-borne resistance genes, can mediate broad-spectrum resistance to most beta -lactams and aminoglycosides.