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Isolation of Salmonella enterica in pigs at slaughter and genetic identity between isolates of porcine and human origin in Northern Italy.
No full textIntroduction: Salmonella spp. is a zoonotic microorganism responsible for food-borne disease worldwide. Even if the EU-trend is decreasing, salmonellosis is still the second most common food-borne disease in the European Union and swine are considered an important reservoir of microorganisms for humans.
Materials and Methods: From June to October 2014, 201 pigs at slaughter were tested for Salmonella spp. in mesenteric lymph nodes. Pigs were reared in 61 farms of four Italian regions (Lombardy, Emilia-Romagna, Veneto and Piedmont) and slaughtered in one abattoir in Emilia-Romagna region. A total of 67 batches of pigs were tested, and 3 animals per batch were randomly selected along the slaughter line. Prior to slaughter, 66 faecal samples were collected at lairage (two per sampling day). Salmonella spp. was detected following the ISO 6579:2002 method for lymph nodes and the ISO 6579/2002/Amd.1:2007 for faecal samples. Serotyping of isolates was performed following the Kauffmann White-Le Minor scheme. Genotyping was carried out by PFGE after digestion of DNA with the restriction enzyme XbaI according to the Pulse Net protocol.
A total of around 3,000 Salmonella isolates from hospitalized human patients of Emilia-Romagna region were typed from October 2011 to October 2014. They were linked to several salmonellosis outbreaks or single cases.
Results: Overall, 39 lymph nodes (19.4%) and 33 faecal samples (50.0%) were found positive for Salmonella. The following Salmonella serovars were detected, listed in order of frequency: S. Derby, S. enterica 1,4,[5],12:i:-, S. Rissen, S. Brandenburg, S. Manhattan, S. London, S. Livingstone, S. Muenchen, S. Stanley, S. Give.
All serovars except S. Stanley were isolated from human cases of infections. Comparing PFGE profiles between the porcine and human compartments, the largest proportion of pulsotypes that were present in both compartments was observed among the isolates of S. enterica 1,4,[5],12:i:- (7 out of the 10 porcine pulsotypes were present in the human isolates) whereas the smallest proportion of shared pulsotypes was observed among the isolates of S. Derby (6 out of the 15 porcine pulsotypes were present in the human isolates). Interestingly, pulsotypes of S. enterica 1,4,[5],12:i:- isolated from pigs did not always correspond to S. enterica 1,4,[5],12:i:-isolates in the human compartment, instead, in some cases they correspond to the biphasic S. Typhimurium.
Conclusions: This study confirms the role of pigs as pathogenic Salmonella strains for humans. Future studies will be necessary to acquire better knowledge on the ecology of S. Typhimurium and its monophasic variant between the porcine and human compartments, considering the importance of these serotypes in human salmonellosis
Antibacterial activity of metal complexes based on cinnamaldehyde thiosemicarbazone analogues
Get PDFThe development of microbial antibiotic resistance has become one of the biggest threats to global health and the search for new molecules active against resistant pathogenic strains is a challenge that must be tackled. In many cases nosocomial infections are caused by bacteria characterized by multi-drug resistance patterns and by their ability to produce biofilms. These properties lead to the persistence of pathogens in the hospital environment. This paper reports the synthesis and characterization of three thiosemicarbazone derivatives based on a compound containing the cinnamaldehyde natural scaffold but possessing different logPow values. These molecules are then used as ligands to prepare complexes of the Cu(II) and Zn(II) ions. All these compounds, ligands and complexes, were screened in vitro on stains of Escherichia coli and Klebsiella pneumoniae for their antibacterial activity. Despite their molecular similarity they revealed variegated behaviors. Only two of them present interesting antimicrobial properties and have also been studied to verify their stability in solution. The compound with the lowest partition coefficient is the most promising. The minimal bactericidal concentration on K. pneumoniae and E. coli of these substances are very interesting and demonstrate that the use of metalloantibiotics is a promising device to fight antibiotic resistance
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Detection of Salmonella enterica in pigs at slaughter and comparison with human isolates in Italy
No full textIn 2013-2014, 201 pigs belonging to 67 batches were tested for Salmonella in their mesenteric lymph nodes (MLN) in one abattoir of Northern Italy. For each batch, faecal material was collected at lairage by swabbing the pen floor for approximately 1600cm2. The aim of this study was to investigate the prevalence of Salmonella in MLN of pigs at slaughter, to assess Salmonella contamination at lairage and to evaluate the effect of lairage duration on its prevalence. Serotyping, XbaI PFGE typing and antimicrobial testing of the isolates were performed. Pig and human Salmonella isolates of the same region of Italy were compared to evaluate possible correlations. Salmonellaenterica was isolated from 19.9% of the MLN and 49.3% of the environmental faecal samples. Nine different serovars were identified among 75 S. enterica isolates. In MLN Salmonella Derby was the most common (52.5%), followed by S. enterica 4,[5],12:i:- (17.5%) and Salmonella Rissen (10.0%). In faecal samples S. Derby was prevalent (51.4%), followed by S. enterica 4,[5], 12:i:- (20.0%) and Salmonella Brandenburg (14.3%). Lairage holding varied between 1 and ≥12h (median value: 2.5h). In pigs held for 1-3h, 14.1% were positive for Salmonella in MLN but the prevalence reached 31.8% when they were held for ≥12h. The contamination of MLN was statistically different (p=0.0045) between the two groups, thus confirming the role of long-lasting lairage in Salmonella contamination of pigs. XbaI PFGE typing detected 36 PFGE types. Twenty-three PFGE types were identified among the 40 MLN isolates and 22 PFGE types among the 35 faecal isolates. A total of 11 PFGE types were shared between the MLN of pigs and the lairage environment. Among S. Derby, 6 shared PFGE types between MLN and faeces were found and among S. enterica 4,[5],12:i:- one PFGE type was common between MLN and the faecal samples. Shared profiles between human and swine isolates of S. Derby, S. enterica 4,[5],12:i:-, S. Rissen, Salmonella Manhattan, S. Brandenburg, Salmonella Livingstone, Salmonella London and Salmonella Muenchen were identified. Among S. Derby and S. enterica 4,[5],12:i:- isolates found in pigs, 6/15 profiles (40.0%) and 8/10 (80.0%) were shared with human isolates. High resistance rates to streptomycin (97.3%), sulphonamide compounds (84.0%) and tetracycline (56.0%) were observed. No resistance was detected to ertapenem and meropenem. High proportions of isolates showed intermediate sensitivity to ciprofloxacin (85.3%) and cefotaxime (66.7%). High sensitivity rates were found to chloramphenicol (96.0%) and trimethoprim/sulfamethoxazole (81.3%
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