135 research outputs found
Detection, semiquantitative enumeration, and antimicrobial susceptibility of Yersinia enterocolitica in pork and chicken meats in Italy.
Yersinia enterocolitica is recognized as an etiological agent of gastroenteritis, lymphadenitis, and chronic sequelae. During 2006 and 2007, 205 samples (125 pork and 80 chicken meats) were collected in Italy and tested for detection and most-probable-number (MPN) enumeration of Y. enterocolitica organisms. The microorganism was isolated from 45 samples (21.9%): 19 (15.2%) pork samples and 26 (32.5%) chicken samples. Y. enterocolitica MPN contamination levels were low, ranging from 0.30 to 1.50/g. Most (94.4%) Y. enterocolitica strains were biotype 1A (serotypes O:3; O:5; O:6,30; O:6,30-6,31; O:7,8-8-8,19; O:8; O:9; O:25,35; O:36; and O nontypeable), and 5.6% of the isolates were bioserotype 2/O:9. All isolates were tested for yadA, ail, inv, ystA, and ystB virulence sequences. The yadA gene was detected in two strains (3.7%) isolated from chicken samples: one Y. enterocolitica 2/O:9 yadA+ ail+ ystA+, and one Y. enterocolitica 1A/O:7,8-8-8,19 yadA+ inv+ ystB+. Two (3.7%) 2/O:9 strains, isolated from pork products, were ail+ ystA+. Most biotype 1A strains were ystB+ (84.3%) and inv+ (39.2%). All strains were sensitive to cefotaxime, ciprofloxacin, chloramphenicol, nalidixic acid, streptomycin, sulfonamide, tetracycline, trimethoprim, and trimethoprim-sulfamethoxazole. Resistance to gentamicin and aztreonam was observed in 1.9% of the isolates. High levels of resistance were detected toward amoxicillin-clavulanic acid (27.8%), ampicillin (75.9%), and erythromycin (100%). The authors hypothesize that Y. enterocolitica pathogenic biotypes are rather uncommon in foods when compared with their isolation rates from animal sources and that chicken meat could be contaminated as well as pig meat and its derived products
Enterobacteriaceae and Salmonella contamination of wild boar (Sus scrofa) carcasses: comparison between different sampling strategies
During 2020, a total of 64 wild boar carcasses were tested for Enterobacteriaceae count (EBC), Salmonella and Yersinia enterocolitica in the abdominal region (i) within 5 h after hunting in the game collection point and (ii) before dressing and processing in the game-handling establishment (GHE) (49 carcassesâaverage time interval between (i) and (ii): 4.3 days). Because of COVID-19 restrictions, 15 carcasses were transported to a near slaughterhouse (average time interval between (i) and (ii): 2.3 days). Mesenteric lymph nodes (MLNs) were collected and tested for Salmonella and Y. enterocolitica. Results are shown in relation to sampling A (49 carcassesâGHE) and sampling B (15 carcassesâslaughterhouse). Sampling A: EBC median values were (i) 2.51 log10 CFU/cm2 and (ii) 2.79 log10 CFU/cm2. EBC increase between (i) and (ii) was statistically significant (pâ=â0.001). Salmonella prevalence on carcasses varied from (i) 2.0 to (ii) 6.1%. Sampling B: EBC median values were (i) 3.1 log10 CFU/cm2 and (ii) 3.32 log10 CFU/cm2. EBC increase between (i) and (ii) was not statistically significant (pâ=â0.191). Salmonella prevalence on carcasses varied from (i) 6.7 to (ii) 0.0%. The prevalence (sampling Aâ+âB) of lymphatic Salmonella carriers was 7.8% (5/64). From carcasses and/or MNLs, the serovars Enteritidis, Typhimurium, Agama, Zaiman and Diarizonae O:50 (z) were detected. Y. enterocolitica was never isolated. Long chilling periods prior to wild game processing should be avoided, and carcasses should be tested at GHE rather than after shooting to proper reflect the microbial load of wild boar meat entering the food chain
Geographical restriction of Hepatitis E virus circulation in wild boars (Sus scrofa) in Emilia-Romagna region, Northern Italy
Hepatitis E virus (HEV) is a singleâstrand RNA virus that causes an acute viral hepatitis in humans. Among its eight recognized genotypes, HEV-3 and HEV-4 are zoonotic, infecting humans, pigs and feral pigs. Recently, HEV-3 has been also detected in red deer, which represents another reservoir of HEV. Consumption of raw pork products (mainly liver sausages), undercooked wild boar meat, raw wild boar liver and deer meat has been responsible for foodborne HEV human worldwide.
From November 2018 to March 2019, liver samples collected from 97 wild boars hunted in Emilia-Romagna region (Northern Italy) were tested for HEV RNA. The hunting area included two territories for an extension of 33 km2, named A (about 13 km2, natural park, deciduous wood) and B (about 20 km2, cultivated fields in proximity of a river) areas. Distance between the two areas ranged between 8 to 10 km. A total of 73 wild boars were hunted in area A, and 24 in area B. HEV RNA was detected by Realâtime RTâPCR in 23/73 liver samples of wild boars living in area A only (31.5% - 95% CI: 22.0-42.8%). The HEV sequences (n=13) clustered within genotype 3. The majority of positives belonged to animals < 12 months (12/25; 48%), followed by subadults (13-24 months) (7/16; 43.8%) and adults (4/32; 12.5%). This difference was found to be statistically significant (p = 0.0024).
In absence of pig farms, the restriction of HEV-positive animals to a well-defined territory of 13 km2 (Boschi di Carrega Regional Park) could hypothetically be related to the presence of red deer (Cervus elaphus), which lived in area A at the beginning of the hunting season. Further studies are needed to confirm or deny our hypothesis
Shiga toxin-producing Escherichia coli O157, O26 and O111 in cattle faeces and hides in Italy
Introduction: Ruminants are regarded as the natural
reservoir for Shiga toxin-producing Escherichia coli
(STEC), especially of serogroup O157.
Materials and methods: During 2011 and 2012,
320 samples (160 faecal samples from the rectum and
160 hide samples from the brisket area) were collected
from 160 cattle at slaughter in Northern Italy during
warm months (May to October). Cattle were reared in
different farms and their age at slaughter ranged
between nine months and 15 years, most of them
being culled cattle (median age: six years; average age:
4.6 years). Samples were tested by immunomagneticseparation
technique for E coli O157 and O26 and by a
screening PCR for stx genes followed by cultural
detection of STEC. The virulence genes stx1, stx2, eae,
and e-hlyA were detected and among stx2-positive
isolates the presence of the stx2a and stx2c variants
was investigated.
Results: Twenty-one of 160 cattle (13.1 per cent; 95
per cent CI 8.3 to 19.4 per cent) were found to be
faecal carriers of STEC. STEC O157 was found in 10
(6.3 per cent) samples, STEC O26 in six (3.8 per cent)
and STEC O111 in one (0.6 per cent). Four isolates
(2.5 per cent) were O not determined (OND). Six out of
160 (3.8 per cent; 95 per cent CI 1.4 to 8.0 per cent)
hide samples were positive for STEC; four hides (2.5
per cent) were contaminated by STEC O157 and two
(1.3 per cent) by STEC O26. In three cattle (1.9
per cent) STEC from both faeces and hides were
detected. Among STEC O157, 87.5 per cent of them
carried the stx2c gene and 12.5 per cent carried both
stx1 and stx2c genes. No O157 isolate harboured stx2a
variant. STEC O26 and O111 carried the stx1 gene
only. One OND strain carried both the stx2a and stx2c
genes.
Conclusions: This study shows that STEC O157 from
cattle can harbour the stx2c variant, which is
associated with haemolytic uraemic syndrome in
humans, and that cattle hides may be a source of
human pathogenic STEC O157 and O26 in the
slaughterhouse environment
Serum albumins are efficient delivery systems for the photosensitizer hypericin in photosensitization-based treatments against Staphylococcus aureus
The naturally occurring photosensitizer hypericin can be effectively delivered to bacterial cells using serum albumins as biocompatible carriers. Using a combination of spectroscopic methods we demonstrate that the photophysics of hypericin is fully preserved when bound to these proteins. Thanks to the excellent transport capabilities of serum albumins, that deliver hypericin to Gram-positive S. aureus, an efficient antibacterial action was observed, with a reduction of up to 8 log in the number of colony-forming units. The photoactive material is fully compatible with the use in food processing environments, and may be exploited as a viable method for decontamination from S. aureus and other Gram-positive bacteria
Detection of Extended- Spectrum Beta-Lactamase producing Escherichia coli from mesenteric lymph nodes of wild boars (Sus scrofa)
Wild boars (Sus scrofa) are increasing in several European countries, including Italy. In areas with intensive animal farming, like the Italian Emilia-Romagna region, they are likely to be exposed to antimicrobialresistant (AMR) bacteria of livestock origin. In 2017-2018, 108 mesenteric lymph nodes samples were collected from 108 wild boars hunted in Parma province, Emilia-Romagna region, to be tested for ESBL- and carbapenemase-producing Escherichia coli. One isolate (WB-21L) out of 108 (0.9%) was phenotypically confirmed as ESBLproducing E. coli. The strain WB-21L was tested by PCR for the genes blaSHV, blaCTX-M, blaTEM, blaAmpC, blaKPC, blaNDM, blaVIM, blaIMP, blaOXA-48, blaSPM, blaBIC, blaSIM, blaDIM, blaGIM, blaAIM, resulting positive for TEM ÎČ-lactamase. Resistance to ampicillin, amoxicillin/clavulanic acid, streptomycin, sulfasomidine, tetracycline and trimethoprim confirmed the multi-resistance nature of the strain WB-21L. Nine E. coli isolates showed resistance to meropenem by the Kirby Bauer test but none of them showed Meropenem MIC values indicative of resistance. In conclusion, the present study shows the presence of ESBL E. coli in wild boars and the possible risk of transfer to game meat handlers and consumers. Future studies are needed to better evaluate the sources of AMR bacteria in wildlife
Survey on carbapenem-resistant bacteria in pigs at slaughter and comparison with human clinical isolates in Italy
This study is focused on resistance to carbapenems and third-generation cephalosporins in Gram-negative microorganisms isolated from swine, whose transmission to humans via pork consumption cannot be excluded. In addition, the common carriage of carbapenem-resistant (CR) bacteria between humans and pigs was evaluated. Sampling involved 300 faecal samples collected from slaughtered pigs and 300 urine samples collected from 187 hospitalised patients in Parma Province (Italy). In swine, MIC testing confirmed resistance to meropenem for isolates of Pseudomonas aeruginosa and Pseudomonas oryzihabitans and resistance to cefotaxime and ceftazidime for Escherichia coli, Ewingella americana, Enterobacter agglomerans, and Citrobacter freundii. For Acinetobacter lwoffii, Aeromonas hydrofila, Burkolderia cepacia, Corynebacterium indologenes, Flavobacterium odoratum, and Stenotrophomonas maltophilia, no EUCAST MIC breakpoints were available. However, ESBL genes (blaCTXM-1, blaCTX-M-2, blaTEM-1, and blaSHV) and AmpC genes (blaCIT, blaACC, and blaEBC) were found in 38 and 16 isolates, respectively. P. aeruginosa was the only CR species shared by pigs (4/300 pigs; 1.3%) and patients (2/187; 1.1%). P. aeruginosa ST938 carrying blaPAO and blaOXA396 was detected in one pig as well as an 83-year-old patient. Although no direct epidemiological link was demonstrable, SNP calling and cgMLST showed a genetic relationship of the isolates (86 SNPs and 661 allele difference), thus suggesting possible circulation of CR bacteria between swine and humans
A comparison of European surveillance programs for Campylobacter in broilers
Campylobacter is an important foodborne pathogen as it is associated with significant disease burden across Europe. Among various sources, Campylobacter infections in humans are often related to the consumption of undercooked poultry meat or improper handling of poultry meat. Many European countries have implemented measures to reduce human exposure to Campylobacter from broiler meat. In this paper, surveillance programs implemented in some European countries is summarized. Our findings reveal that many European countries test neck skin samples for Campylobacter as per the Process Hygiene Criterion (PHC) set by the European Regulation. Variations to the legal plan are seen in some countries, as in Norway and Iceland, where weekly sampling is performed during infection peak periods only, or in Iceland, where the Campylobacter limit is set at 500 CFU/g instead of 1000 CFU/g. Furthermore, northern European countries have implemented national Campylobacter surveillance plans. Denmark tests cloaca and leg skin samples at the slaughterhouses and meat samples at the retail, while Finland, Norway, and Sweden test caeca at slaughterhouses. In contrast, Iceland tests feces on farms. Iceland and Norway test flocks close to the slaughter date and when a farm tests positive, competent authority implement measures such as logistic slaughter, heat treatment or freeze the meat from these flocks. In Iceland, frozen meat is further processed prior to being put on the market. While the incidence of campylobacteriosis has declined in all European countries except France since the introduction of PHC in 2018, it is uncertain whether this decrease is due to prevalence reduction or underreporting during the COVID-19 pandemic. Future investigations with more comprehensive data, devoid of potential confounding factors, are necessary to validate this potential trend. However, it is evident that the implementation of national action plans can be successful in reducing the incidence of human campylobacteriosis, as demonstrated by Iceland
Calixarenes Incorporating Sulfonamide Moieties: Versatile Ligands for Carbonic Anhydrases Inhibition
Carbonic anhydrases (CAs) continue to represent a relevant pharmaceutical target. The need of selective inhibitors and the involvement of these metalloenzymes in many multifaceted diseases boost the search for new ligands able to distinguish among the different CA isoforms, and for multifunctional systems simultaneously able to inhibit CAs and to interfere with other pathological events by interacting with additional targets. In this work, we successfully explored the possibility of preparing new CAs ligands by combining calixarenes with benzensulfonamide units. Inhibition tests towards three human CA isoforms evidenced, for some of the ligands, Ki values in the nanomolar range and promising selectivity. X-ray and molecular modeling studies provided information on the mode of binding of these calixarene derivatives. Thanks to the encouraging results and the structural features typical of the calixarene scaffold, it is then possible to plan for the future the design of multifunctional inhibitors for this class of widely spread enzymes
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