1,720,988 research outputs found
Molecular epidemiological insights into colistin-resistant and carbapenemases-producing clinical Klebsiella pneumoniae isolates
Purpose: Carbapenemases-producing Klebsiella pneumoniae are challenging antimicrobial therapy of hospitalised patients, which is further complicated by colistin resistance. This study describes molecular epidemiological insights into colistin-resistant and carbapenemases- producing clinical K. pneumoniae. Patients and methods: Cultures collected from 26 hospitalised patients during 2014–2017 in the main hospital in Molise Region, central Italy, were characterized. The minimum inhibitory concentration for 19 antibiotics was determined, including carbapenems and colistin. Prevalence of resistance-associated genes was investigated through PCR, detecting blaKPC, blaGES, blaVIM, blaIMP, blaNDM, blaOXA-48, blaCTX-M, blaTEM, blaSHV, and mcr- 1,2,3,4,5,6,7,8. The mgrB gene was also analysed in colistin-resistant strains by PCR and sequencing assays. K. pneumoniae were typed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Results: Twenty out of 26 K. pneumoniae were phenotypically resistant to carbapenems and 19 were resistant to colistin. All isolates harbored blaKPC, and blaSHV, blaTEM and blaVIM were further the most common resistance-associated genes. In colistin-resistant strains, mcr- 1,2,3,4,5,6,7,8 variants were not detected, while mutations and insertion elements in mgrB were observed in 68.4% (n=13) in 31.6% (n=6) isolates, respectively. PFGE revealed 12 clusters and 18 pulsotypes at 85% and 95% cut-off, while the Sequence Types ST512 (n=13, 50%), ST101 (n=10, 38.5%), ST307 (n=2, 7.7%) plus a novel ST were detected using MLST. Conclusion: All K. pneumoniae showed a multidrug-resistant phenotype, particularly to carbapenems and colistin. According to national data, blaKPC was the prevailing carbapenemase, followed by blaVIM, while blaTEM and blaSHV were among the most frequent betalactamases. Consistent with previous reports in Italy, ST512 was the most common clone, particularly during 2014–15, whilst ST101 became dominant in 2016–17. Colistin resistance was mainly associated with deleterious mutations and transposon in the mgrB gene. Improvements of surveillance, compliance with infection prevention procedures and antimicrobial stewardship are essential to limit the spread of resistant K. pneumoniae
A single-arm study to evaluate skin tolerance, effectiveness and adherence to use of an alcohol-based hand rub solution among hospital nurses
Background: Hand hygiene is considered as the most important strategy for preventing healthcare infections. Objective: In this single-arm study, skin tolerance, effectiveness and prolonged efficacy, and adherence to use an alcohol-based hand rub (ABHR) solution among hospital nurses was evaluated. Methods: Nurses were recruited in the main hospital of Molise Region, Central Italy. Skin reactions during 12-week follow-up were self-reported by nurses and, when occurring examined by hospital dermatologist. Samples were collected from palms and fingertips before and after ABHR, also at random times during work. Results: Dermatological reactions were not reported by 20 nurses (15 female and 5 male, aged 30–59 years) after product use. Microbial counts decreased by 99% (2Log10) in 75%, with higher reduction in palm than fingertips (99% vs 70% respectively). Analysis of six randomly collected samples after 10–20 and 30–40 min from the last use showed a satisfactory prolonged efficacy. Discussion: Beyond high effectiveness to reduce transient microbiota, no skin reactions were observed, likely due to the camomile, thyme and eucalyptus extracts contained within the gel. This study, addressing technical questions of a commercialised product, provides useful information for public health authorities faced with a choice of hand disinfectants, evaluating cost-effectiveness and cost-benefit in the light of the huge amount of these products needed at hospital level
Tracking multidrug-resistant Klebsiella pneumoniae from an Italian hospital: molecular epidemiology and surveillance by PFGE, RAPD and PCR-based resistance genes prevalence
Antimicrobial-resistant Klebsiella pneumoniae represent a global public health concern. K. pneumoniae strains isolated during 2010 and 2014–2016 within a single hospital of Molise Region, Central Italy, were analyzed testing antimicrobial susceptibility, clonality by pulsed-field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD)-PCR, and prevalence of carbapenem resistance genes by PCR. Forty isolates (23 wild-type in 2010 and 17 non-wild-type in 2014–2016) were collected from hospitalized patients (65.2 ± 18.1 years old, 75% male, 80% from intensive care unit—ICU). K. pneumoniae showed multidrug-resistant profiles and 15 resistotypes were identified (discriminatory power D = 0.88). The 69.6 and 17.4% of isolates in 2010 resulted intermediate and resistant to imipenem, respectively, and 91.3% was sensitive to meropenem, while 88.2% of isolates of 2014–2016 were resistant to both antibiotics. PFGE identified 16 clusters versus 23 by RAPD, 26 pulsotypes versus 33 RAPD patterns (D ≥ 0.97). PFGE separated strains according to isolation period and identified an outbreak occurred in the ICU during December 2014 and January 2015. No strains harbored blaGES, blaIMP, blaNDM−1, and blaOXA−48 genes, as well as AmpC plasmid-mediated beta-lactamases genes. Only K. pneumoniae isolated during 2014–2016 were blaKPC positive. Prevalence of blaVIM was 87 and 76.5% during 2010 and 2014–2016, respectively. No strains colistin-resistant harbored mcr-1 plasmid-mediated resistance gene. The study findings underline an increased circulation of multidrug-resistant K. pneumoniae within the hospital, and the acquisition of carbapenem resistance mechanism. The implementation of surveillance and molecular characterization of isolates are needed to identify outbreaks, reduce the spread of resistance, and guide empirical therapy
Identification of emesis-causing Bacillus cereus strains by polymerase chain reaction: preliminary results
Bacillus cereus can give rise to two distinct forms of food borne disease, the diarrehoealand emetic syndromes. The second one is characterized by symptoms of nausea andvomiting which appear within 1–4 h from ingestion of the contaminated food. The emeticsyndrome is believed to be associated with an emetic toxin preformed in the food.Cooked rice and farinaceous foods such as pasta, noodles and cakes are consideredthe most common vehicles (Shinagawa et al., 1996). The emetic toxin is a cyclic dodecadepsipeptidenamed cereulide. It is resistant to pH changes and high temperature, resemblingthe staphylococcal enterotoxins and its activity is evident at low doses(Agata et al., 2002). For the detection of enterotoxic Bacillus cereus strains diagnosticmolecular assays such as PCR–based methods and immunological methods based on thedetection of the Hbl-L2 component (BCET-RPLA) have been performed. On the contrary,are not yet available commercial diagnostic kits for the detection of Bacillus cereusemetic strains (Guinebretiere et al., 2002). Three different methods for identificationof the emetic toxin have been described in recent years: the Hep-2 (larynx carcinoma)cells vacuolation assay, LC-MS analysis and a biological assay based on cereulideinducedinhibition of the motility in boar spermatozoa. According to Andersson et al.(2004), the cereulide producing Bacillus cereus strains are not able to hydrolyze starch.Recently, Ehling-Schulz and coworkers (2004) have identified a genomic DNA fragmentof 635 pb codifying for cereulide, and developed specific primers for the detection ofemetic Bacillus cereus strains.[...
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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