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1.
Chronobiol Int ; 41(3): 369-377, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38326980

RESUMO

Dogs are the common pets adopted by humans, and their circadian behavior and physiology are influenced by human habits. In many families, there is a change of lifestyle with respect to the natural daylight (NDL) cycle. Exposure to constant light disrupts some central and peripheral circadian rhythms. The aim of the present study was to improve the knowledge about the circadian changes of clock components in the peripheral blood in dogs housed under NDL and constant light (LL) conditions. Blood samples were collected on five female Beagle dogs (2 years old, 14 ± 0.5 kg) every 4 hours for a 24-hour period during an NDL (Sunrise 05:05 h - Sunset 20:55 h) and 24-hour period of constant light (LL). Blood samples were stored in a PAX gene Blood RNA Tube, real-time RT-quantitative polymerase chain reaction was performed to determine Clock, Per1-3, and Cry1-2 gene expression. During the NDL, all genes investigated showed robust diurnal daily rhythmicity. During the constant light, only Clock maintained its daily rhythmicity. Clock acrophase was observed close to sunrise (ZT 0) and was statistically different from the other clock genes except for Per3. Per3 daily oscillations were not statistically significant. No differences were observed among the clock genes tested in the amplitude and robustness values. Our results can be considered preliminary data to provide new insights into the adaptation mechanism of the canine peripheral circadian clock. The persistence of Clock gene expression during the LL indicated the presence of an endogenously generated signal in blood. Because peripheral blood is an easily accessible sample in dogs, the analysis of clock gene expression in this tissue could be useful to investigate the adaptive capacity of this species housed in different environmental conditions linked to the owner's lifestyle.


Assuntos
Relógios Circadianos , Fotoperíodo , Cães , Animais , Feminino , Humanos , Pré-Escolar , Ritmo Circadiano/genética , Relógios Circadianos/genética , RNA Mensageiro/metabolismo , Expressão Gênica
2.
Microorganisms ; 11(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36838350

RESUMO

Leptospirosis is a zoonosis of public health concern. Its prevalence in stray animals in the South of Italy is unknown. This study aimed to investigate Leptospira spp. prevalence in 1009 stray animals. Out of them, 749 were alive animals, including 358 dogs (316 from Palermo and 42 from Ragusa) and 391 cats (359 from Palermo and 32 from Ragusa), and 260 were corpses (216 dogs and 44 cats) randomly collected in Sicily. Dogs and cats underwent a serological screening by Microscopic Agglutination Test and a molecular investigation by Real-Time PCR targeting lipL32. Corpses were subjected to Real-Time PCR. Serological analyses showed a prevalence of 1.12% (4/358) for dogs and 0.26% (1/391) for cats, with the only positive cat coming from Palermo. Serogroup Icterohaemorrhagiae serovar Icterohaemorrhagiae or Copenhageni, followed by Canicola and Bratislava, were the most spread among dogs, while the serological positive cat reacted with Hardjo serogroup. Two urine (2/32, 6.25%) and one blood (1/391, 0.26%) samples of cats, all from Ragusa, were positive at Real-Time PCR for pathogenic Leptospira spp. Sequencing analyses showed the presence of L. interrogans serogroup Icterohaemorrhagiae serovar Icterohaemorrhagiae or Copenhageni in one of the positive urine samples and in the positive blood sample. Analyses on corpses showed a prevalence of 1.85% (4/216) in Sicilian dog kidney samples, while all corpses of cats resulted in negative. Genotyping analysis showed a genetic relatedness between cat and human isolates. Results show Leptospira spp. circulation among Sicilian stray animals. The genetic relatedness between cat and human isolates suggests a possible common infection source.

3.
Pathogens ; 12(2)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36839554

RESUMO

Chagas disease is a chronic systemic infection transmitted by Trypanosoma cruzi. Its life cycle consists of different stages in vector insects and host mammals. Trypanosoma cruzi strains cause different clinical manifestations of Chagas disease alongside geographic differences in morbidity and mortality. Natural killer cells provide the cytokine interferon-gamma in the initial phases of T. cruzi infection. Phagocytes secrete cytokines that promote inflammation and activation of other cells involved in defence. Dendritic cells, monocytes and macrophages modulate the adaptive immune response, and B lymphocytes activate an effective humoral immune response to T. cruzi. This review focuses on the main immune mechanisms acting during T. cruzi infection, on the strategies activated by the pathogen against the host cells, on the processes involved in inflammasome and virulence factors and on the new strategies for preventing, controlling and treating this disease.

4.
Front Public Health ; 11: 1098965, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778569

RESUMO

To investigate the influence of geographic constrains to mobility on SARS-CoV-2 circulation before the advent of vaccination, we recently characterized the occurrence in Sicily of viral lineages in the second pandemic wave (September to December 2020). Our data revealed wide prevalence of the then widespread through Europe B.1.177 variant, although some viral samples could not be classified with the limited Sanger sequencing tools used. A particularly interesting sample could not be fitted to a major variant then circulating in Europe and has been subjected here to full genome sequencing in an attempt to clarify its origin, lineage and relations with the seven full genome sequences deposited for that period in Sicily, hoping to provide clues on viral evolution. The obtained genome is unique (not present in databases). It hosts 20 single-base substitutions relative to the original Wuhan-Hu-1 sequence, 8 of them synonymous and the other 12 encoding 11 amino acid substitutions, all of them already reported one by one. They include four highly prevalent substitutions, NSP12:P323L, S:D614G, and N:R203K/G204R; the much less prevalent S:G181V, ORF3a:G49V and N:R209I changes; and the very rare mutations NSP3:L761I, NSP6:S106F, NSP8:S41F and NSP14:Y447H. GISAID labeled this genome as B.1.1 lineage, a lineage that appeared early on in the pandemic. Phylogenetic analysis also confirmed this lineage diagnosis. Comparison with the seven genome sequences deposited in late 2020 from Sicily revealed branching leading to B.1.177 in one branch and to Alpha in the other branch, and suggested a local origin for the S:G118V mutation.


Assuntos
COVID-19 , Evolução Molecular , Genoma Viral , SARS-CoV-2 , Humanos , Mapeamento Cromossômico , COVID-19/epidemiologia , COVID-19/virologia , Filogenia , SARS-CoV-2/genética , Sicília/epidemiologia
5.
Animals (Basel) ; 12(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35268152

RESUMO

Leptospirosis is a re-emerging zoonosis of worldwide significance; a wide spectrum of wild and domestic animal species act as natural or accidental hosts. Swine can act as maintenance or accidental hosts of pathogenic Leptospira spp. This study aimed at investigation of Leptospira spp. prevalence and diversity in slaughtered pigs in southern Italy (Sicily). In total, 55 samples of kidneys and blood were collected. Microscopic agglutination test and real-time PCR were performed to detect pathogenic and intermediately pathogenic Leptospira. Partial rpoB gene sequencing and multi-locus sequence typing (MLST) were performed to characterize Leptospira species. The analysis showed a seropositivity rate of 16.4%, with Australis representing the most frequently identified serogroup (63.64%); Pomona and Sejroe were detected with a prevalence of 27.27% and 9.09%, respectively. Pathogenic Leptospiral DNA was detected in 2 kidney samples (3.64%). Leptospira were identified through MLST as L. borgpetersenii serovar Tarassovi (serogroup Tarassovi). Obtained data confirmed the presence of Leptospira infection among pigs in southern Italy, suggesting that management of these animals may be considered an occupational risk for humans.

6.
Vet Sci ; 9(2)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35202336

RESUMO

Bovine leptospirosis is an infectious zoonotic disease causing reproductive problems and economic losses in livestock. This work reports, for the first time in Sicily (South Italy), an outbreak of Leptospira interrogans serogroup Pomona that occurred in cattle farms within the Nebrodi Park and was mainly characterized by full-term abortion. Blood and urine samples were collected at different time points from animals of six different farms (Farms A-F) sharing the same grazing area. Research of antibodies against pathogenic Leptospira species in serum samples was carried out via Micro Agglutination Test (MAT). Urine samples were subjected to pathogen isolation and molecular analyses via TaqMan Real Time-PCR. Genotyping of Leptospira species was obtained by Multi-locus sequence typing. MAT detected antibodies against Leptospira interrogans serogroup Pomona in serum samples of all the farms. Pathogenic Leptospira spp. DNA and culture isolation was obtained from urine samples. Genotyping confirmed the excretion of L. interrogans serogroup Pomona. This study describes clinical manifestations, diagnostic implications and epidemiological characteristics of an outbreak in cattle due to L. interrogans Pomona in a protected multi-host area, where domestic and wild animals share the same habitat, suggesting a role of wild species in transmission and persistence of Pomona serogroup among cattle.

7.
Ital J Food Saf ; 10(3): 9722, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34733802

RESUMO

Staphyloccoccus aureus is the major cause of mastitis in small ruminants in the Mediterranean farms causing severe losses to dairy industry. Antibiotic treatment has been the most common approach to control these infections. Aim of this study was to investigate antimicrobial resistance (AMR), virulence factors and biofilm-related genes of 84 Sicilian strains of S. aureus isolated from sheep and goats milk during two different periods δT1 (2006-2009) and δT2 (2013-2015). Kirby Bauer method and Polymerase Chain Reaction (PCR) were utilized to monitor AMR and related genes (mecA, tetK, tetM, ermA, ermC). Moreover, toxin genes (tsst-1, sea-see, seg-sej, and sep) and biofilm genes (bap, ica, sasC) were studied. Twenty-six isolates (30.9%) showed multidrug resistance. The two groups showed similar results with exception for higher values of resistance for tilmicosin and lower for sulfamethoxazole and vancomycin of the second group. MecA gene was detected in one isolate. Tetracycline resistance was higher than 20%, with an increase in δT2 group. Toxin genes were found in 5 isolates (5.9%), belonging of δT2 group, while 57 of isolates (67.8%) showed biofilm related genes. The high presence of multi-resistant isolates suggests the need of more responsible use of antibiotic therapy for the control of these infections.

8.
Vet Med Sci ; 7(6): 2463-2472, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34505400

RESUMO

BACKGROUND: West Nile Disease (WND) is a zoonotic mosquito-borne infection involving viral pathogens, human and animal hosts, vectors and environment. Cooperation among medical, veterinary and entomological fields has been promoted by the Italian Public Health Authorities, and an integrated West Nile Virus (WNV) Surveillance Plan has been in force in Italy since 2016 to prevent the transmission risk of WND to humans through an early detection of viral circulation by animal and entomological surveillance. This managing model is unique in Europe. OBJECTIVES: This survey aimed at presenting the 'One Health' approach applied in 2016 to the first autochthonous human case of West Nile Neuroinvasive Disease (WNND) in Sicily (Southern Italy). METHODS: Serological (anti-WNV IgM and IgG ELISA, anti-WNV neutralizing antibodies) and molecular tests were conducted on blood, liquor and urine of a 38-year-old man with encephalitis and meningitis. Overall, 2704 adult culicides from 160 mosquito catches were morphologically identified. Female mosquitoes were analysed in pools for WNV RNA detection. Serological (anti-WNV IgM and IgG ELISA) and molecular analyses for WNV were carried out in 11 horses, 271 chickens and two dogs sampled in farms around the man's residence. RESULTS AND CONCLUSIONS: WNND was confirmed by serological analysis on patient's liquor and serum. Collected mosquito species included Culex pipiens (93.56%, CI95% 92.64%-94.49%), Aedes albopictus (5.25%, CI95% 4.41%-6.09%), Culex hortensis (0.59%, CI95% 0.30%-0.88%), Culiseta longiareolata (0.55%, CI95% 0.27%-0.83%) and Anopheles maculipennis s.l. (0.04%, CI95% -0.04% to 0.11%). Mosquito pools were negative for WNV RNA. Two dogs (100%) and two horses (18.18%, CI95% -4.61 to 40.97%) resulted positive for anti-WNV specific antibodies. The 'One Health' approach allowed to report the first human neuroinvasive WND in Sicily and to confirm the local circulation of WNV in animals of the same area where the clinical case occurred, defining the autochthonous origin of the infection.


Assuntos
Doenças do Cão , Doenças dos Cavalos , Saúde Única , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Galinhas , Cães , Feminino , Doenças dos Cavalos/epidemiologia , Cavalos , Humanos , Mosquitos Vetores , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária
9.
Foods ; 10(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203938

RESUMO

Contamination of bivalve mollusks with human pathogenic viruses represents a recognized food safety risk. Thus, monitoring programs for shellfish quality along the entire food chain could help to finally preserve the health of consumers. The aim of the present study was to provide up-to-date data on the prevalence of enteric virus contamination along the shellfish production and distribution chain in Sicily. To this end, 162 batches of mollusks were collected between 2017 and 2019 from harvesting areas, depuration and dispatch centers (n = 63), restaurants (n = 6) and retail stores (n = 93) distributed all over the island. Samples were processed according to ISO 15216 standard method, and the presence of genogroup GI and GII norovirus (NoV), hepatitis A and E viruses (HAV, HEV), rotavirus and adenovirus was investigated by real-time reverse transcription polymerase chain reaction (real-time-RT PCR), nested (RT)-PCR and molecular genotyping. Our findings show that 5.56% of samples were contaminated with at least one NoV, HAV and/or HEV. Contaminated shellfish were sampled at production sites and retail stores and their origin was traced back to Spain and several municipalities in Italy. In conclusion, our study highlights the need to implement routine monitoring programs along the whole food chain as an effective measure to prevent foodborne transmission of enteric viruses.

10.
Vet Ital ; 55(2): 149-155, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31274176

RESUMO

One of the major constraints in the diagnosis of animal brucellosis is the cross-reactivity that occurs between Brucella and Yersinia surface antigens. With the aim to find a method to distinguish Brucella from Yersinia infection, the expansion of interferon gamma producing (IFN-γ+) T cell subsets obtained from peripheral blood mononuclear cells (PBMC) isolated from cattle either infected by Brucella abortus or experimentally immunized with Yersinia enterocolitica O:9 were compared. The lymphocytes were analyzed by flow cytometry after PBMC were in vitro re-exposed to Yersinia or Brucella antigens. The results highlighted a statistically significant difference in the expansion of the CD4+ and CD8+ IFN-γ+ T cells occurring when PBMC of animals immunized with Yersinia are in vitro exposed to Y. enterocolitica O:9 antigen but not to Brucella antigen. This method could thus be suggested in those cases where results obtained by serodiagnosis need to be further clarified.


Assuntos
Brucella abortus/fisiologia , Brucelose Bovina/imunologia , Interferon gama/imunologia , Yersiniose/imunologia , Yersinia enterocolitica/fisiologia , Animais , Bovinos , Citometria de Fluxo/veterinária , Leucócitos Mononucleares/imunologia
11.
Int J Infect Dis ; 80: 66-72, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639406

RESUMO

OBJECTIVES: Enteric viruses are responsible for foodborne and waterborne infections affecting a large number of people. Data on food and water viral contamination in the south of Italy (Sicily) are scarce and fragmentary. The aim of this study was to evaluate the presence of viral contamination in food, water samples, and surface swabs collected in Sicily METHODS: The survey was conducted on 108 shellfish, 23 water samples (seawater, pipe water, and torrent water), 52 vegetables, one peach and 17 berries, 11 gastronomic preparations containing fish products and/or raw vegetables, and 28 surface swabs. Hepatitis A virus (HAV), genogroup GI, GII, and GIV norovirus (NoV), enterovirus (EV), rotavirus (RoV), hepatitis E virus (HEV), adenovirus (AdV), and bocavirus (BoV) were detected by nested (RT) PCR, real-time PCR, and sequence analysis. RESULTS: The most frequently detected viruses in shellfish were HAV (13%), NoV (18.5%), and EV (7.4%). Bocavirus was found in 3.7%, HEV in 0.9%, and AdV in 1.9% of the molluscs. Of the 23 water samples, 21.7% were positive for GII NoV and 4.3% for RoV and HEV genotype 3. Of the 70 vegetable samples, 2.9% were positive for NoV GI (GI.5 and GI.6), 2.9% for EV, and 1.4% for HEV. In the gastronomic preparations, only one EV (9%) was detected. No enteric viruses were detected in the berries, fruit, or swabs analyzed. CONCLUSIONS: Molecular surveillance of water and food samples clearly demonstrated that human pathogenic viruses are widely found in aquatic environments and on vegetables, and confirmed the role of vegetables and bivalve molluscs as the main reservoirs.


Assuntos
Enterovirus/isolamento & purificação , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Microbiologia da Água , Animais , DNA Viral/isolamento & purificação , Água Potável/virologia , Frutas/virologia , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite E/isolamento & purificação , Humanos , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Alimentos Marinhos/virologia , Frutos do Mar/virologia , Sicília , Verduras/virologia , Poluição da Água
12.
Infect Dis (Lond) ; 51(1): 26-31, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29969052

RESUMO

BACKGROUND: Toxoplasmosis is one of the most frequent parasitic infections in animals causing reproductive disorders and thus notable economic losses in productivity. Among food animals, pigs along with sheep and goats possess the highest incidence of Toxoplasma gondii cysts in meat, and play a role as a source of human infection. METHODS: The commercial ELISA kit (PrioCHECK® Toxoplasma Ab SR, Prionics Schlieren-Zurich, Switzerland) for the detection of specific antibodies against T. gondii in swine serum was compared with a commercial IFAT (indirect fluorescent antibody test) (Toxo-Spot IF, bioMérieux, France), used as the reference test. RESULTS: The kappa value obtained comparing the results performed on sera by ELISA with the by IFAT was 1. By a receiver operating characteristics curve analysis, the commercial ELISA had a relative sensitivity of 100%, and a relative specificity of 100% respect to IFAT. CONCLUSIONS: The commercial ELISA showed a very good agreement with the commercial IFAT in the detection of serum antibodies to Toxoplasma in pigs. Our study confirmed the usefulness of the commercial ELISA kit for the detection of antibodies against T. gondii in pigs, representing a valuable tool to improve the diagnostic activity for T. gondii in swine populations at the farm level or at the slaughterhouse, contributing to the control of this widespread infection.


Assuntos
Anticorpos Antiprotozoários/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Doenças dos Suínos/diagnóstico , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico , Animais , Incidência , Curva ROC , Sensibilidade e Especificidade , Suínos , Suíça
13.
Vet Ital ; 54(3): 225-236, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-30575000

RESUMO

Canine distemper virus (CDV) is the etiologic agent of distemper in dogs. It exhibits an elevated potential of crossing species barriers, infecting a wide range of wild and domestic carnivores. Of its encoding genes, hemagglutinin (H) shows high heterogeneity, and it was used to determine the relationship between CDV strains due to its variability and key role in determining cell tropism, host shift, and in eliciting a protective immune response. This study analysed the full-length H gene sequence of Arctic-like CDV strains collected from dogs in Italy during a period in which an increased activity of CDV diffusion was observed. The common amino acid changes and features of Arctic-like CDV strains collected from 2011 to 2016 in Europe were described, providing an updated analysis of the genomic features. A comparison with CDV vaccine strains was carried out to evaluate the increased genomic difference with CDV Arctic-like field strains. This study provides a complete and updated analysis of the current spreading strains of Arctic-like lineage and the main amino acid variations in the hemagglutinin gene sequence circulating in Italy. Moreover, it provides novel information regarding the evolution of the most recent CDV Arctic-like lineage strains collected in Europe.


Assuntos
Vírus da Cinomose Canina/classificação , Vírus da Cinomose Canina/genética , Animais , Vírus da Cinomose Canina/isolamento & purificação , Cães/virologia , Itália , RNA Viral/análise
14.
Ital J Food Saf ; 7(1): 6911, 2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29732324

RESUMO

The present work was carried out to investigate the microbiological profile of Sicilian ewes' ricotta cheeses during fifteen years of investigations (2002-2016). The samples were collected between those conferred to the Istituto Zooprofilattico Sperimentale della Sicilia (IZSSi) Adelmo Mirri, Palermo (Italy), by the competent authority during official control, by food business operator in HACCP systems and in research projects. Enterobacteriaceae, Escherichia coli and coagulase-positive staphylococci (CPS) were found only in some samples. Bacillus cereus was detected in c.a. 16% of samples but the level of contaminations did not reach the threshold that leads to significant toxin production. Pathogenic bacteria such as Listeria monocytogenes, Salmonella spp. and Brucella spp. were never detected. Furthermore, a total of 47 of lactic acid bacteria (LAB) strains were identified at species level by sequencing the 16S rRNA gene, resulting in the identification of 10 species belonging to four genera Enterococcus, Lactobacillus, Lactococcus and Leuconostoc, commonly employed as starter and non starter cultures in different traditional cheese. Results of this study highlighted an improvement of the hygienic conditions of the Sicilian ewes' ricotta cheeses during the last ten years of investigation. This observation was confirmed from reduction of undesired microorganisms such as Enterobacteriaceae, E.coli and CPS, used to define the process hygiene criteria. However, in order to improve the final quality of this product are needed further strategy such as the dairy makers training, with the aim to apply a good hygienic practices during the production.

15.
Infect Genet Evol ; 61: 67-73, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29548803

RESUMO

Canine parvovirus (CPV) is the etiological agent of a severe viral disease of dogs. After its emergence in late 1970s, the CPV original type (CPV-2) was rapidly and totally replaced by three antigenic variants named CPV-2a, CPV-2b and CPV-2c. CPV has an evolutionary rate nearest to those of RNA viruses, with consequences on disease diagnosis and epidemiology. This paper reports the molecular characterization of eight CPV-2a strains collected from dogs in Italy in 2016-2017. Genetic analysis was conducted on a CPV genomic region encompassing both open reading frames (ORFs) encoding for nonstructural (NS1-NS2) and structural proteins (VP1-VP2). Sequence analysis indicates new and unreported sequence changes, mainly affecting the VP2 gene, which included the mutation Tyr324Leu. This study represents the first evidence of a new CPV-2a mutant (VP2 324Leu) and illustrates the importance of a continuous molecular survey in order to obtain more information on effective spread of new CPV mutants.


Assuntos
Doenças do Cão/virologia , Infecções por Parvoviridae/virologia , Parvovirus Canino/genética , Animais , Anticorpos Antivirais/sangue , DNA Viral/genética , Cães , Itália , Tipagem Molecular , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/classificação , Parvovirus Canino/imunologia , Filogenia , Mutação Puntual/genética , Análise de Sequência de DNA
16.
Ital J Food Saf ; 6(1): 6191, 2017 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28299290

RESUMO

Listeria monocytogenes is a pathogen frequently found in dairy products, and its growth is difficult to control. Bacteriocin-like inhibitory substances (BLIS), produced by lactic acid bacteria (LAB), having proven in vitro anti-Listeria activity, could provide an innovative approach to control L. monocytogenes; however, this application needs to be evaluated in vivo. In this study, twenty LAB strains isolated from different Sicilian dairy environments were tested for control of growth of L. monocytogenes in three different experimental trials. First, raw and UHT milk were inoculated with LAB strains alone, and LAB strains mixed with L. monocytogenes. Second, mini-cheeses containing LAB and/or L. monocytogenes were produced. Third, two traditional Sicilian cheeses inoculated with a multi-strain LAB mixture combined with L. monocytogenes were produced. The addition of BLIS produced by LAB to milk and in mini-cheese production was unable to inhibit the growth of L. monocytogenes. However, an anti-Listeria effect was observed in the Pecorino Siciliano cheeses, where, after 15 days of ripening, the cheeses with added LAB had fewer L. monocytogenes compared to the control cheeses with no added LAB, while in the Vastedda della valle del Belìce cheeses, the multi-strain LAB mixture completely prevented the growth of L. monocytogenes.

17.
Ital J Food Saf ; 5(1): 5503, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-27800430

RESUMO

Bacteriocins are antimicrobial proteins produced by bacteria that inhibit the growth of other bacteria with a bactericidal or bacteriostatic mode of action. Many lactic acid bacteria (LAB) produce a high diversity of different bacteriocins. Bacteriocinogenic LAB are generally recognised as safe (GRAS) and useful to control the frequent development of pathogens and spoilage microorganisms. For this reason they are commonly used as starter cultures in food fermentations. In this study, the authors describe the results of a screening on 699 LAB isolated from wooden vat surfaces, raw milk and traditional Sicilian cheeses, for the production of bacteriocin-like inhibitory substances, by comparing two alternative methods. The antagonistic activity of LAB and its proteinaceous nature were evaluated using the spot-on-the-lawn and the well-diffusion assay (WDA) and the sensitivity to proteolytic (proteinase K, protease B and trypsin), amylolytic (a-amylase) and lipolytic (lipase) enzymes. The indicator strains used were: Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella enteritidis. A total of 223 strains (belonging to the species Enterococcus spp., Lactobacillus spp., Pediococcus spp., Streptococcus spp., Leuconostoc spp. and Lactococcus lactis) were found to inhibit the growth of Listeria monocytogenes by using the spot-on-the-lawn method; only 37 of these were confirmed by using the WDA. The direct addition of bacteriocin-producing cultures into dairy products can be a more practical and economic option for the improvement of the safety and quality of the final product.

18.
Food Microbiol ; 52: 31-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26338114

RESUMO

The biofilms of 12 wooden vats used for the production of the traditional stretched cheeses Caciocavallo Palermitano and PDO Vastedda della valle del Belìce were investigated. Salmonella spp. and Listeria monocytogenes were never detected. Total coliforms were at low numbers with Escherichia coli found only in three vats. Coagulase-positive staphylococci (CPS) were below the enumeration limit, whereas lactic acid bacteria (LAB) dominated the surfaces of all vats. In general, the dominance was showed by coccus LAB. Enterococci were estimated at high numbers, but usually between 1 and 2 Log cycles lower than other LAB. LAB populations were investigated at species and strain level and for their technological properties relevant in cheese production. Eighty-five strains were analysed by a polyphasic genetic approach and allotted into 16 species within the genera Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Pediococcus and Streptococcus. Enterococcus faecium was found in all wooden vats and the species most frequently isolated were Enterococcus faecalis, Lactococcus lactis, Leuconostoc mesenteroides, Pediococcus acidilactici and Streptococcus thermophilus. The study of the quantitative data on acidification rate, autolysis kinetics, diacetyl production, antibacterial compound generation and proteolysis by cluster and principal component analysis led to the identification of some strains with promising dairy characteristics. Interestingly, a consistent percentage of LAB was bacteriocin-like inhibitory substances (BLIS) producer. Thus, the microbial biofilms of the wooden vats analysed in this study might contribute actively to the stability of the final cheeses.


Assuntos
Queijo/microbiologia , Lactobacillaceae/metabolismo , Madeira/microbiologia , Animais , Bovinos , Ácido Láctico/metabolismo , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/isolamento & purificação , Leite/microbiologia , Dados de Sequência Molecular , Filogenia
19.
Ital J Food Saf ; 4(1): 4509, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-27800376

RESUMO

Traditional Sicilian cheese productions are carried out employing traditional wooden vats, called tina. Many studies have highlighted the beneficial role of wooden dairy equipment by contributing to enriching the milk microflora and improving the acidification processes. The present work was undertaken to evaluate the safety of the wooden vats used to coagulate milk. To this purpose, the different microbial populations hosted onto the internal surfaces of the vats used to produce two different stretched cheeses, namely Caciocavallo Palermitano and Vastedda della valle del Belìce DOP, were investigated for the presence of spoilage and pathogenic microorganisms as well as for bacteria with inhibitory effect in vitro against pathogenic microorganisms. A wide biodiversity of protechnological lactic acid bacteria (LAB), in terms of species, was revealed. Several LAB inhibited the growth of Listeria monocytogenes ATCC 7644. The wooden vats analysed resulted safe for three main findings: absence of the main pathogenic species, presence of high levels of LAB, anti-Listeria activity of many LAB.

20.
J Water Health ; 12(3): 452-64, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25252349

RESUMO

During March 2011 an outbreak of gastroenteritis occurred in Santo Stefano di Quisquina, Agrigento, Sicily, Italy. Within two weeks 156 cases were identified among the 4,965 people living in the municipality. An epidemiological investigation was conducted to characterize the outbreak and target the control measures. A case was defined as a person developing diarrhea or vomiting during February 27-March 13, 2011. Stool specimens were collected from 12 cases. Norovirus (NoV) genotype GII.4 variant New Orleans 2009 was identified in stool samples from 11 of 12 cases tested (91.7%). Epidemiological investigations suggested a possible association with municipal drinking water consumption. Water samples from the public water system were tested for NoV and a variety of genotypes were detected during the first 3 months of surveillance, including GII.4 strains belonging to different variants from that involved in the gastroenteritis outbreak. Contamination of the well and springs supplying the public water network was eventually thought to be the source of the NoV contamination.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/prevenção & controle , Surtos de Doenças , Água Potável/virologia , Gastroenterite/epidemiologia , Gastroenterite/prevenção & controle , Norovirus/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Caliciviridae/virologia , Fezes/virologia , Feminino , Gastroenterite/virologia , Humanos , Testes de Fixação do Látex , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Sicília/epidemiologia , Adulto Jovem
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