Letteratura scientifica selezionata sul tema "Salmonella enteritidis Genetics"
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Articoli di riviste sul tema "Salmonella enteritidis Genetics"
1
Wu, Daichao, Da Teng, Xiumin Wang, Changsong Dai e Jianhua Wang. "Saccharomyces boulardii prevention of the hepatic injury induced by Salmonella Enteritidis infection". Canadian Journal of Microbiology 60, n. 10 (ottobre 2014): 681–86. http://dx.doi.org/10.1139/cjm-2014-0259.
Testo completoAbstract (sommario):
Salmonella enterica subsp. enterica serovar Enteritidis (Salmonella Enteritidis) is the predominant cause of serovar-associated food-borne outbreaks in many countries and causes significant clinical symptoms of liver injury, enteritis, and diarrheal diseases. Saccharomyces boulardii is used in clinical application for prophylaxis and the treatment of a variety of diseases caused by bacterial infection. We used a mouse model of Salmonella Enteritidis infection, which included pretreatment with S. boulardii, to reveal the protection mechanisms of S. boulardii against Salmonella Enteritidis infection, including the translocation of Salmonella Enteritidis to the liver 10 days after Salmonella Enteritidis challenge, and the colonisation of Salmonella Enteritidis and the formation of hepatic tissue lesions in mice after Salmonella Enteritidis challenge on the 10th day. Compared with Salmonella Enteritidis infection in mice, S. boulardii decreased Salmonella Enteritidis translocation to the liver by 96%, and 99% of Salmonella Enteritidis colonised the cecum on the 10th day. Saccharomyces boulardii also abated hepatic tissue injury caused by the infiltration of neutrophilic granulocytes, lymphocytes, and plasmocytes by decreasing the translocation of Salmonella to the liver. These findings demonstrated that S. boulardii is an effective agent in the prevention of the hepatic injury induced by Salmonella Enteritidis infection in a mouse model.
2
Desin, Taseen S., Claudia S. Mickael, Po-King S. Lam, Andrew A. Potter e Wolfgang Köster. "Protection of epithelial cells from Salmonella enterica serovar Enteritidis invasion by antibodies against the SPI-1 type III secretion system". Canadian Journal of Microbiology 56, n. 6 (giugno 2010): 522–26. http://dx.doi.org/10.1139/w10-034.
Testo completoAbstract (sommario):
Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) is one of the major causes of bacterial food-borne illness in humans. During the course of infection, Salmonella Enteritidis uses 2 type III secretion systems (T3SS), one of which is encoded on Salmonella pathogenicity island 1 (SPI-1). SPI-1 plays a major role in the invasion process. In the present study, we evaluated the effect of sera against the SPI-1 T3SS components on invasion in vitro using polarized human intestinal epithelial cells (Caco-2). Antisera to SipD protected Caco-2 cells against entry of wild-type Salmonella Enteritidis. On the other hand, sera against InvG, PrgI, SipA, SipC, SopB, SopE, and SopE2 did not affect Salmonella Enteritidis entry. To illustrate the specificity of anti-SipD mediated inhibition, SipD-specific antibodies were depleted from the serum. Antiserum depleted of SipD-specific antibodies lost its capacity to inhibit Salmonella Enteritidis entry. Thus, we demonstrate for the first time that antibodies against the SPI-1 needle tip protein (SipD) inhibit Salmonella Enteritidis invasion and that the SipD protein may be an important target in blocking SPI-1 mediated virulence of Salmonella Enteritidis.
3
Nadin-Davis, S., L. Pope, D. Ogunremi, B. Brooks e J. Devenish. "A real-time PCR regimen for testing environmental samples for Salmonella enterica subsp. enterica serovars of concern to the poultry industry, with special focus on Salmonella Enteritidis". Canadian Journal of Microbiology 65, n. 2 (febbraio 2019): 162–73. http://dx.doi.org/10.1139/cjm-2018-0417.
Testo completoAbstract (sommario):
A real-time PCR (qPCR) regimen, using up to six genetic targets, was developed to rapidly detect Salmonella and in particular identify Salmonella Enteritidis. The test regimen was first evaluated using a reference culture collection of Salmonella to confirm the appropriateness of the selected targets, which included up to three genetic markers for discrimination of Salmonella Enteritidis from other Salmonella serovars commonly found in poultry facilities. The qPCR procedure was then compared with culture methods used to detect Salmonella using a collection of enrichment broths previously generated from 239 environmental samples collected from a large number of hatchery facilities across Canada over several years. The qPCR regimen facilitated specific detection of Salmonella Enteritidis, and on a sample basis, it showed excellent agreement with the culture methods. Moreover, in many cases, qPCR detected Salmonella earlier in the culture process than did the culture method. Application of this method will significantly shorten test times and allow more timely identification of infected poultry premises, thereby improving present programmes aimed at controlling Salmonella Enteritidis at the environmental source.
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Fandiño, Luz Clemencia, e Noel Verjan. "A common Salmonella Enteritidis sequence type from poultry and human gastroenteritis in Ibagué, Colombia". Biomédica 39 (1 maggio 2019): 50–62. http://dx.doi.org/10.7705/biomedica.v39i1.4155.
Testo completoAbstract (sommario):
Introducción. Salmonella Enteritidis es una de las mayores causas de salmonelosis en el mundo, siendo los huevos contaminados y la carne de pollo cruda sus principales fuentes de infección. En Ibagué, Colombia, se identificaron los principales serovares circulando en granjas, superficies de huevos y canales de pollo, sin embargo, se desconoce si esos serovares son responsables de gastroenteritis.
Objetivo. Evaluar la relación genética entre aislamientos de Salmonella Enteritidis de aves de corral y humanos con gastroenteritis mediante multilocus sequence typing (MLST).
Materiales y métodos. Se aisló Salmonella spp., de casos clínicos de gastroenteritis (n=110). Se realizó test de sensibilidad antibiótica, seguido de serotipificación y tipificación por medio de MLST y se comparó S. Enteritidis de humanos frente a S. Enteritidis de granjas ponedoras y de huevo comercializado (n=6).
Resultados. Se aislaron 10 cepas de Salmonella spp., a partir de heces de humanos con gastroenteritis. Se obtuvo una prevalencia de Salmonella spp. de 9.09%, siendo S. Enteritidis (n=4), S. Typhymurium (n=2), S. Newport (n=1), S. Grupensis (n=1), S. Uganda (n=1) y S. Braenderup (n=1) los serotipos presentes en pacientes con gastroenteritis. El MLST indico que un tipo de secuencia común (ST11) de S. Enteritidis estuvo presente en todas las tres fuentes y mostraron el mismo patrón de resistencia antibiótica.
Conclusión. S. Enteritidis ST11 constituye un vínculo entre el consumo/manipulación de huevos contaminados y gastroenteritis humana en Ibagué. Son necesarios estudios complementarios para conocer si otros serovares de Salmonella aislados de carne de pollo cruda también se asocian con la gastroenteritis humana.
5
Elgueta, Estefanía, Javier Mena e Pedro A. Orihuela. "Hydroethanolic Extracts of Haplopappus baylahuen Remy and Aloysia citriodora Palau Have Bactericide Activity and Inhibit the Ability of Salmonella Enteritidis to Form Biofilm and Adhere to Human Intestinal Cells". BioMed Research International 2021 (27 gennaio 2021): 1–9. http://dx.doi.org/10.1155/2021/3491831.
Testo completoAbstract (sommario):
We analysed whether the hydroethanolic extracts from leaves of Haplopappus baylahuen Remy (bailahuen) and Aloysia citriodora Palau (cedron) inhibit the growth and ability of Salmonella Enteritidis to form biofilms and to adhere to human intestinal epithelial cells. Herein, we first determined the total phenolic content and antioxidant and antibacterial activities of the extracts. Then, Salmonella Enteritidis was treated with the extracts to analyse biofilm formation by scanning electronic microscopy and the violet crystal test. We also measured the efflux pump activity of Salmonella Enteritidis since biofilm formation is associated with this phenomenon. Furthermore, the human intestinal cell line Caco-2 was infected with Salmonella Enteritidis pretreated with the extracts, and 30 min later, the number of bacteria that adhered to the cell surface was quantified. Finally, we determined by qPCR the expression of genes associated with biofilm formation, namely, the diguanilate cyclase AdrA protein gene (adrA) and the BapA protein gene (bapA), and genes associated with adhesion, namely, the transcriptional regulator HilA (hilA). The phenolic content and antioxidant and bactericide activities were higher in bailahuen than in the cedron extract. Biofilm formation was inhibited by the extracts in a dose-dependent manner, while the activity of efflux pumps was decreased only with the cedron extract. Adhesion to Caco-2 cells was also inhibited without differences between doses and extracts. The extracts decreased the expression of adrA; with the cedron extract being the most efficient. The expression of hilA is affected only with the cedron extract. We concluded that hydroethanolic extracts of bailahuen and cedron differentially inhibit the growth of Salmonella Enteritidis and affect its the ability to form biofilms and to adhere to human intestinal epithelial cells. These results highlight the presence of molecules in bailahuen and cedron with a high potential for the control of the Salmonella Enteritidis pathogenesis.
6
Zhao, Shaohua, Cong Li, Chih-Hao Hsu, Gregory H. Tyson, Errol Strain, Heather Tate, Thu-Thuy Tran, Jason Abbott e Patrick F. McDermott. "Comparative Genomic Analysis of 450 Strains of Salmonella enterica Isolated from Diseased Animals". Genes 11, n. 9 (1 settembre 2020): 1025. http://dx.doi.org/10.3390/genes11091025.
Testo completoAbstract (sommario):
Salmonella is a leading cause of bacterial infections in animals and humans. We sequenced a collection of 450 Salmonella strains from diseased animals to better understand the genetic makeup of their virulence and resistance features. The presence of Salmonella pathogenicity islands (SPIs) varied by serotype. S. Enteritidis carried the most SPIs (n = 15), while S. Mbandaka, S. Cerro, S. Meleagridis, and S. Havana carried the least (n = 10). S. Typhimurium, S. Choleraesuis, S. I 4,5,12:i:-, and S. Enteritidis each contained the spv operon on IncFII or IncFII-IncFIB hybrid plasmids. Two S. IIIa carried a spv operon with spvD deletion on the chromosome. Twelve plasmid types including 24 hybrid plasmids were identified. IncA/C was frequently associated with S. Newport (83%) and S. Agona (100%) from bovine, whereas IncFII (100%), IncFIB (100%), and IncQ1 (94%) were seen in S. Choleraesuis from swine. IncX (100%) was detected in all S. Kentucky from chicken. A total of 60 antimicrobial resistance genes (ARGs), four disinfectant resistances genes (DRGs) and 33 heavy metal resistance genes (HMRGs) were identified. The Salmonella strains from sick animals contained various SPIs, resistance genes and plasmid types based on the serotype and source of the isolates. Such complicated genomic structures shed light on the strain characteristics contributing to the severity of disease and treatment failures in Salmonella infections, including those causing illnesses in animals.
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Wilson, Catherine N., Angeziwa Chunga, Clemens Masesa, Brigitte Denis, Niza Silungwe, Sithembile Bilima, Heather Galloway, Melita Gordon e Nicholas A. Feasey. "Incidence of invasive non-typhoidal Salmonella in Blantyre, Malawi between January 2011-December 2019". Wellcome Open Research 7 (29 aprile 2022): 143. http://dx.doi.org/10.12688/wellcomeopenres.17754.1.
Testo completoAbstract (sommario):
Background: The Malawi-Liverpool Wellcome Trust Clinical Research Programme (MLW) has undertaken sentinel surveillance of bloodstream infection and meningitis at Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi for 20 years. Previously, three epidemics of Salmonella bloodstream infection have been identified. Here we provide updated surveillance data on invasive non-typhoidal Salmonella disease from 2011 – 2019. Methods: Surveillance data describing trends in invasive non-typhoidal Salmonella disease and associated antimicrobial susceptibility profiles are presented for the period January 2011 – December 2019. Results: Between January 2011-December 2019, 128,588 blood cultures and 40,769 cerebrospinal fluid cultures were processed at MLW. Overall, 1.00% of these were positive for S. Typhimurium, 0.10% for S. Enteritidis, and 0.05% positive for other Salmonella species. Estimated minimum incidence of invasive non-typhoidal Salmonella (iNTS) disease decreased from 21/100,000 per year in 2011 to 7/100,000 per year in 2019. Over this period, 26 confirmed cases of Salmonella meningitis were recorded (88.5% S. Typhimurium). Between 2011-2019 there was a substantial decrease in proportion of S. Typhimurium (78.5% to 27.7%) and S. Enteritidis (31.8% in 2011 to 0%) that were multidrug-resistant. Resistance to fluoroquinolones and third-generation generation cephalosporins (3GC) remained uncommon, however 3GC increased amongst Salmonella spp. and S. Typhimurium in the latter part of the period. Conclusions: The total number of iNTS bloodstream infections decreased between 2011-2019. Although the number multidrug resistance (MDR) S. Typhimurium and S. Enteritidis isolates has fallen, the number of MDR isolates of other Salmonella spp. has increased, including 3GC isolates.
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Rychlik, Ivan, Renata Karpiskova, Marcela Faldynova e Frantisek Sisak. "Computer-assisted restriction endonuclease analysis of plasmid DNA in field strains of Salmonella enteritidis". Canadian Journal of Microbiology 44, n. 12 (1 dicembre 1998): 1183–85. http://dx.doi.org/10.1139/w98-112.
Testo completoAbstract (sommario):
Computer-assisted restriction endonuclease analysis of plasmid DNA in field strains of Salmonella enterica serovar Enteritidis (S. enteritidis) is described. The procedure consists of plasmid DNA purification, its digestion with restriction endonuclease TaqI, electrophoresis, charge-coupled device camera scanning of the gels, and an analysis of the restriction patterns with the software Gel Manager. The system allowed us to analyse, in detail, results of plasmid profiling in more than 600 field strains of S. enteritidis. In addition to plasmid-free and virulence plasmid only containing strains, 15 additional plasmid types were detected. All the images and detailed protocols are available at the Web site http://www.clark.cz/vri/salmon.htm.Key words: computer analysis, plasmid type, Salmonella, DNA fingerprinting, epidemiology.
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Portrait, V., S. Gendron-Gaillard, G. Cottenceau e A. M. Pons. "Inhibition of pathogenicSalmonellaenteritidisgrowth mediated byEscherichia colimicrocin J25 producing strains". Canadian Journal of Microbiology 45, n. 12 (1 dicembre 1999): 988–94. http://dx.doi.org/10.1139/w99-106.
Testo completoAbstract (sommario):
For the first time, microcin-producing strains showing inhibitory activities against enteropathogen Salmonella enteritidis were isolated from poultry intestinal contents. Among the numerous strains isolated, two strains of Escherichia coli, named J02 and J03, showing the greatest activities against S. enteritidis, were studied. Biochemical tests and purification identified the main antagonist compound produced as microcin J25. In order to evaluate the protective potential of E. coli J02 and J03 against S. enteritidis infection, the ability of these strains to inhibit growth of S. enteritidis was investigated in mixed culture. A strong antagonist activity was obtained with a preculture phase of the active strain in minimal medium before incubation with S. enteritidis. In a bioreactor experiment simulating the chicken gastric and intestinal tract environment, a mixture of the two strains E. coli J02 and J03, provided an enhanced inhibitory effect. Microcinogenic strain activities were not affected by bile, pancreatic enzymes addition, or acidic conditions. These results suggest the relevant role of microcin-producing microorganisms in microbial intestinal ecology. To conclude, this study shows that microcin J25 strains could exert a beneficial protective effect against S. enteritidis growth in situ.Key words: microcin J25, Salmonella, mixed cultures.
10
Lan, Dan, XinYu Xun, YaoDong Hu, NianZhen Li, ChaoWu Yang, XiaoSong Jiang e YiPing Liu. "Research on the Effect of Pediococcus pentosaceus on Salmonella enteritidis-Infected Chicken". BioMed Research International 2020 (10 ottobre 2020): 1–10. http://dx.doi.org/10.1155/2020/6416451.
Testo completoAbstract (sommario):
Salmonella enteritidis can cause significant morbidity and mortality in humans and economic loss in the animal industry. Improving the innate immunity is an effective method to prevent S. enteritidis infection. Pediococcus pentosaceus is a Gram-positive coccus which had probiotics properties. Numerous previously published studies reported that probiotics were beneficial to gut microbiota by changing the intestinal flora structure and inhibiting the harmful microbial growth to enhance the innate immunity. We investigated the immunological effects of P. pentosaceus on Salmonella-infected chickens by the following experiment. A total of 120 broilers from AA line were fed and divided into 2 groups (treated and control groups) for the experiment from day 1. The control group was fed with the basic diet, while the treated group was fed with the basic diet adding P. pentosaceus microcapsule with the bacterial concentration of 1 g/kg in the feed and bacterial counts 2.5 × 10 9 CFU/g. All the birds were given with 0.5 ml of S. enteritidis bacterial suspension (109 CFU/ml) through oral cavity at day 9. The number of dead birds was recorded and used in the analysis. The bacterial culture method and quantitative real-time PCR analysis were used to evaluate the effects of P. pentosaceus on chickens infected with S. enteritidis and to ascertain the mechanism of the effect. The results showed that the P. pentosaceus could restrain the pathogenicity of S. enteritidis and reduce the death rate from 44.4% to 23.3%. The flora in the caecum exhibited “rising-declining” trends, and the gene (TLR4, MyD88, TRAF6 NF-κB, IFN-β, TNF-a, IL6, and IL8) expression pattern was different between the experimental and control group. P. pentosaceus as a probiotic may competitively inhibit the growth of S. enteritidis and control the inflammatory response through regulating the gene expression which involved in the toll-like receptor pathway and inflammation pathway.
Tesi sul tema "Salmonella enteritidis Genetics"
1
Mmolawa, Princess Tlou. "Molecular analysis of temperate phages in Salmonella enterica serovar Typhimurium DT 64 isolated in Australia". Title page, contents and summary only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phm6855.pdf.
Testo completoAbstract (sommario):
Files on accompanying CD-ROM: Appendix III Phages ST64T and ST64B sequences, are in rtf format. Bibliography: leaves 279-324. System requirements for accompanying CD-ROM: IBM or compatible ; Microsoft Word or compatible to read rtf files.
2
Botten, James Alfons Desmond. "Role of sefD and sefR in the biogenesis of Salmonella enterica serovar Enteritidis SEF14 fimbriae". Title page, abstract and contents only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phb7512.pdf.
Testo completo
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Chevenon, Marie. "Functional validation of the genetic architecture of «Salmonella» persistence in 129S6 mice and the impact of Ses1 (Nramp1) on the transcriptome of «Salmonella» enteritidis during chronic carriage". Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110593.
Testo completoAbstract (sommario):
Salmonella Typhimurium and Salmonella Enteritidis cause a food-borne disease resulting in gastroenteritis. To study the persistence of Salmonella during the late phase of infection, a mouse model was developed using C57BL/6J mice that clear the bacteria completely from the spleen and lymph nodes within 42 days post-infection and 129S6 mice that become chronic carriers. Linkage analyses using a cross between C57BL/6J and 129S6 mice led to the mapping of ten quantitative trait loci, Ses1 to Ses10, affecting Salmonella persistence in mice. In the females, Ses3 showed significant effects on bacterial clearance and two significant interactions between Ses1.2 and Ses4 and between Ses1.2 and Ses5. To functionally validate in vivo the interaction between Ses1.2 and Ses4 or Ses5, we created double congenic mice. Bacterial counts in the spleen and the liver demonstrated that both the 129S6.B6-Ses1.2/Ses4 and the 129S6.B6-Ses1.2/Ses5 mice clear Salmonella Enteritidis more efficiently than 129S6 or single congenic mice at day 42 post-infection validating the interaction terms identified by statistical analyses. We also tested the candidacy of Hamp as the gene underlying Ses5 by quantitative complementation test in which we did not detect a significant interaction between Hamp and Ses5. In addition, the effect of Nramp1 on the Salmonella expression of virulence factors, notably mgtB and phoP was investigated ex vivo and in vivo. To validate our hypothesis in vivo, we present the creation of ΔmgtB and ΔphoPQ Salmonella Enteritidis mutants.Salmonella Typhimurium et Salmonella Enteritidis sont des agents microbiens qui causent une gastroentérite d'origine alimentaire. Pour étudier le portage asymptomatique des salmonelles, nous avons développé un modèle chez la souris en utilisant les souris C57BL/6J qui arrivent à éliminer complètement la bactérie de la rate et des ganglions lymphatiques en l'espace de 42 jours après infection et les souris 129S6 qui deviennent des porteurs chroniques. En utilisant une approche de criblage génomique par locus, nous avons identifié dix loci (Ses1-Ses10) affectant la persistance de Salmonella chez la souris. Chez les femelles, le locus Ses3 et les interactions épistatiques entre les loci Ses1.2 et Ses4 et Ses1.2 et Ses5 participent à l'élimination de la bactérie. Pour valider les deux interactions in vivo, nous avons créé des nouvelles lignées congéniques combinatoires. L'énumération des bactéries dans la rate et le foie démontre que les souris 129S6.B6-Ses1.2/Ses4 et 129S6.B6-Ses1.2/Ses5 arrivent à éliminer Salmonella Enteritidis plus efficacement que les souris 129S6 ou les souris congéniques qui comprennent seulement un des locus au jour 42 après infection, validant les interactions identifiées par analyses statistiques. Nous avons testé la candidature du gène Hamp pour l'intervalle Ses5 en exécutant un test de complémentation pour lequel nous n'avons pas détecté d'interaction significative entre Ses5 et Hamp. De plus, l'influence de Nramp1 sur l'expression de facteurs virulents de Salmonella, notamment mgtB et phoP, a été investigué ex vivo et in vivo. Pour valider notre hypothèse in vivo, nous présentons la création de mutants bactériens pour les deux gènes.
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Andrigheto, Cristiano. "Disseminação de Salmonella Enteritidis isoladas em uma cadeia produtiva industrial avícola: determinação do perfil de resistência a antimicrobianos e caracterização genotípica". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-25072017-152730/.
Testo completoAbstract (sommario):
Salmonella é um dos principais agentes de enfermidades transmitidas por alimentos em diversos países, sendo a carne de frango um dos principais veículos envolvidos em surtos. O Brasil vem se destacando como um dos maiores exportadores mundiais deste alimento. O ambiente de criação das aves é apontado como um importante foco de infecção das aves e o ambiente industrial de abate e processamento é importante na disseminação deste ·microrganismo. Na busca pela produção de alimentos seguros do ponto de vista microbiológico, uma das ferramentas utilizadas é a subtipagem de microrganismos isolados ao longo da cadeia de produção, que permite determinar rotas de contaminação do produto final. Os objetivos deste trabalho são: o estudo da disseminação dos subtipos de Salmonella Enteritidis nas várias etapas de uma cadeia de produção industrial de carne de frango, empregando-se diversos métodos de subtipagem e a determinação da resistência a antimicrobianos destas cepas. 108 isolados de Salmonella Enteritidis dos fagotipos PT1, PT4 e PT7a foram obtidos nos anos de 2002 e 2003, a partir de amostras ambientais e de frango relativas a sete sub-regiões de uma cadeia produtiva industrial avícola. Os perfis de resistência destes isolados foram determinados frente a antimicrobianos de uso humano e veterinário e eles foram submetidos a subtipagem por PFGE, RAPO, ribotipagem e PCR-ribotipagem. Foram detectados 21 perfis de resistência diferentes, com 6,5% das cepas sensíveis a todas as drogas, 33,3% resistentes a um ou dois antimicrobianos e 83,3% apresentando resistência intermediária a até quatro deles. Os níveis relativamente elevados de resistência são preocupantes e a diminuição da pressão seletiva deve ser um objetivo para os produtores de aves. De modo geral, a subtipagem permitiu separar as cepas em 13 genótipos, com elevada similaridade entre si. Porém, a maior parte das cepas (69,4%) pertenceu a apenas três deles, que foram encontrados ao longo de toda a cadeia produtiva. A ribotipagem foi o método que apresentou o melhor poder discriminatório (D = 0,701), porém nem todas as cepas foram tipáveis por este método. Não foram encontradas correlações entre os perfis de resistência a antimicrobianos e fagotipos, nem entre genótipos e fagotipos. Porém, dois genótipos proximamente correlacionados e predominantemente encontrados em uma sub-região reuniram apenas cepas com resistência intermediária ou resistentes exclusivamente à furazolidona. A similaridade elevada entre os genótipos evidencia a origem clonal das cepas.Salmonella is one of the most important foodborne disease agents all over the world, and chicken is recognized as an important vehicle of the infection. Chicken production in Brazil has increased in the last couple of years and the country is now ranked 2nd as producer/exporter of this commodity. For this reason there is an increased concern over the safety of these goods. This study deals with the dissemination, antimicrobial resistance, and genetic characterization of S. Enteritidis strains isolated from an industrial chicken production chain. 108 isolates, phagetypes PT1, PT4 and PT7a, were obtained at different steps of the commercial production from farm to frozen cuts, and the broilers were from different producers supplying the same processing plant. Tests for susceptibility to 12 human and veterinary antimicrobial agents were performed. The strains were also typed by PFGE, RAPO, ribotyping, and PCR-ribotyping. 6.5% of the strains were susceptible to the 12 drugs tested and 33.3% were resistant to 1 or 2 of them. Intermediate resistance to up to 4 agents was observed in 83.3% of the isolates. Combining all the typing methods allowed the division of the strains in 13 genotypes with elevated degree of similarity. However, 69.4% of the strains belonged to 3 main phagetypes spread along the production chain. There was no correlation between phagetypes and genotypes, or phagetypes and resistance profiles. However, most strains from one sub-region were from 2 genotypes and showed intermediate resistance to, or were resistant to furazolidone. The high degree of similarity amongst the genotypes indicates the clonal origin of the strains. The relatively high resistance to antimicrobial agents is a cause of concern and trying to diminish the selective pressure has to be a goal for broiler producers.
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Mmolawa, Princess Tlou. "Molecular analysis of temperate phages in Salmonella enterica serovar Typhimurium DT 64 isolated in Australia / Princess Tlou Mmolawa". Thesis, 2001. http://hdl.handle.net/2440/21765.
Testo completoAbstract (sommario):
Files on accompanying CD-ROM: Appendix III Phages ST64T and ST64B sequences, are in rtf format.Bibliography: leaves 279-324.
System requirements for accompanying CD-ROM: IBM or compatible ; Microsoft Word or compatible to read rtf files.
xii, 325, [8] leaves, [116] leaves of plates : ill. (some col.) ; 30 cm. + 1 CD-ROM (4 3/4 in.)
Thesis (Ph.D.)--University of Adelaide, Dept. of Molecular Biosciences, 2002?
Capitoli di libri sul tema "Salmonella enteritidis Genetics"
1
Benjamin, W. H., W. E. Briles, W. D. Waltman e D. E. Briles. "EFFECT OF GENETICS AND PRIOR SALMONELLA ENTERITIDIS INFECTION ON THE ABILITY OF CHICKENS TO BE INFECTED WITH S. ENTERITIDIS". In Colonization Control of Human Bacterial Enteropathologens in Poultry, 365–69. Elsevier, 1991. http://dx.doi.org/10.1016/b978-0-12-104280-6.50044-7.
Testo completo
2
Ogunremi, Dele, Ruimin Gao, Rosemarie Slowey, Shu Chen, Olga Andrievskaia, Sadjia Bekal, Lawrence Goodridge e Roger C. Levesque. "Tracking Salmonella Enteritidis in the Genomics Era: Clade Definition Using a SNP-PCR Assay and Implications for Population Structure". In Salmonella spp. - A Global Challenge. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98309.
Testo completoAbstract (sommario):
Salmonella enterica serovar Enteritidis (or Salmonella Enteritidis, SE) is one of the oldest members of the genus Salmonella, based on the date of first description and has only gained prominence as a significant bacterial contaminant of food over the last three or four decades. Currently, SE is the most common Salmonella serovar causing foodborne illnesses. Control measures to alleviate human infections require that food isolates be characterized and this was until recently carried out using Pulsed-Field Gel Electrophoresis (PFGE) and phage typing as the main laboratory subtyping tools for use in demonstrating relatedness of isolates recovered from infected humans and the food source. The results provided by these analytical tools were presented with easy-to-understand and comprehensible nomenclature, however, the techniques were inherently poorly discriminatory, which is attributable to the clonality of SE. The tools have now given way to whole genome sequencing which provides a full and comprehensive genetic attributes of an organism and a very attractive and superior tool for defining an isolate and for inferring genetic relatedness among isolates. A comparative phylogenomic analysis of isolates of choice provides both a visual appreciation of relatedness as well as quantifiable estimates of genetic distance. Despite the considerable information provided by whole genome analysis and development of a phylogenetic tree, the approach does not lend itself to generating a useful nomenclature-based description of SE subtypes. To this end, a highly discriminatory, cost-effective, high throughput, validated single nucleotide based genotypic polymerase chain reaction assay (SNP-PCR) was developed focussing on 60 polymorphic loci. The procedure was used to identify 25 circulating clades of SE, the largest number so far described for this organism. The new subtyping test, which exploited whole genome sequencing data, displays the attributes of an ideal subtyping test: high discrimination, low cost, rapid, highly reproducible and epidemiological concordance. The procedure is useful for identifying the subtype designation of an isolate, for defining the population structure of the organism as well as for surveillance and outbreak detection.
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Shah, Devendra H., Jacob R. Elder, Kim L. Chiok e Narayan C. Paul. "Genetic Basis of Salmonella Enteritidis Pathogenesis in Chickens". In Producing Safe Eggs, 187–208. Elsevier, 2017. http://dx.doi.org/10.1016/b978-0-12-802582-6.00010-0.
Testo completoRapporti di organizzazioni sul tema "Salmonella enteritidis Genetics"
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Cahaner, Avigdor, Susan J. Lamont, E. Dan Heller e Jossi Hillel. Molecular Genetic Dissection of Complex Immunocompetence Traits in Broilers. United States Department of Agriculture, agosto 2003. http://dx.doi.org/10.32747/2003.7586461.bard.
Testo completoAbstract (sommario):
Objectives: (1) Evaluate Immunocompetence-OTL-containing Chromosomal Regions (ICRs), marked by microsatellites or candidate genes, for magnitude of direct effect and for contribution to relationships among multiple immunocompetence, disease-resistance, and growth traits, in order to estimate epistatic and pleiotropic effects and to predict the potential breeding applications of such markers. (2) Evaluate the interaction of the ICRs with genetic backgrounds from multiple sources and of multiple levels of genetic variation, in order to predict the general applicability of molecular genetic markers across widely varied populations. Background: Diseases cause substantial economic losses to animal producers. Emerging pathogens, vaccine failures and intense management systems increase the impact of diseases on animal production. Moreover, zoonotic pathogens are a threat to human food safety when microbiological contamination of animal products occurs. Consumers are increasingly concerned about drug residues and antibiotic- resistant pathogens derived from animal products. The project used contemporary scientific technologies to investigate the genetics of chicken resistance to infectious disease. Genetic enhancement of the innate resistance of chicken populations provides a sustainable and ecologically sound approach to reduce microbial loads in agricultural populations. In turn, animals will be produced more efficiently with less need for drug treatment and will pose less of a potential food-safety hazard. Major achievements, conclusions and implications:. The PI and co-PIs had developed a refined research plan, aiming at the original but more focused objectives, that could be well-accomplished with the reduced awarded support. The successful conduct of that research over the past four years has yielded substantial new information about the genes and genetic markers that are associated with response to two important poultry pathogens, Salmonella enteritidis (SE) and Escherichia coli (EC), about variation of immunocompetence genes in poultry, about relationships of traits of immune response and production, and about interaction of genes with environment and with other genes and genetic background. The current BARD work has generated a base of knowledge and expertise regarding the genetic variation underlying the traits of immunocompetence and disease resistance. In addition, unique genetic resource populations of chickens have been established in the course of the current project, and they are essential for continued projects. The US laboratory has made considerable progress in studies of the genetics of resistance to SE. Microsatellite-marked chromosomal regions and several specific genes were linked to SE vaccine response or bacterial burden and the important phenomenon of gene interaction was identified in this system. In total, these studies demonstrate the role of genetics in SE response, the utility of the existing resource population, and the expertise of the research group in conducting such experiments. The Israeli laboratories had showed that the lines developed by selection for high or low level of antibody (Ab) response to EC differ similarly in Ab response to several other viral and bacterial pathogens, indicating the existence of a genetic control of general capacity of Ab response in young broilers. It was also found that the 10w-Ab line has developed, possibly via compensatory "natural" selection, higher cellular immune response. At the DNA levels, markers supposedly linked to immune response were identified, as well as SNP in the MHC, a candidate gene responsible for genetic differences in immunocompetence of chickens.
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Mateva, Gergana, Karl Pedersen, Gitte Sorensen, Mia Torpdahl e Hristo Daskalov. Genetic Polymorphism and Antimicrobial Resistance of Salmonella Enterica Serovar Enteritidis Isolates from Food Chain Sources. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, luglio 2021. http://dx.doi.org/10.7546/crabs.2021.07.04.
Testo completo
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Redmond, Sarah Beth, e Susan J. Lamont. Genetic Differences in Chicken Heterophil mRNA Expression in Response to In-Vitro Stimulation with Salmonella enteritidis. Ames (Iowa): Iowa State University, gennaio 2009. http://dx.doi.org/10.31274/ans_air-180814-755.
Testo completo
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Lamont, Susan J., Michael G. Kaiser e Jennifer H. Cheeseman. Genetic Line Differences in Cytokine mRNA Expression of Peripheral Blood Leukocytes Exposed to Salmonella enteritidis In-Vitro. Ames (Iowa): Iowa State University, gennaio 2005. http://dx.doi.org/10.31274/ans_air-180814-1064.
Testo completo
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Willis, C., F. Jorgensen, S. A. Cawthraw, H. Aird, S. Lai, M. Chattaway, I. Lock, E. Quill e G. Raykova. A survey of Salmonella, Escherichia coli (E. coli) and antimicrobial resistance in frozen, part-cooked, breaded or battered poultry products on retail sale in the United Kingdom. Food Standards Agency, maggio 2022. http://dx.doi.org/10.46756/sci.fsa.xvu389.
Testo completoAbstract (sommario):
Frozen, breaded, ready-to-cook chicken products have been implicated in outbreaks of salmonellosis. Some of these outbreaks can be large. For example, one outbreak of Salmonella Enteritidis involved 193 people in nine countries between 2018 and 2020, of which 122 cases were in the UK. These ready-to-cook products have a browned, cooked external appearance, which may be perceived as ready-to-eat, leading to mishandling or undercooking by consumers. Continuing concerns about these products led FSA to initiate a short-term (four month), cross-sectional surveillance study undertaken in 2021 to determine the prevalence of Salmonella spp., Escherichia coli and antimicrobial resistance (AMR) in frozen, breaded or battered chicken products on retail sale in the UK. This study sought to obtain data on AMR levels in Salmonella and E. coli in these products, in line with a number of other FSA instigated studies of the incidence and nature of AMR in the UK food chain, for example, the systematic review (2016). Between the beginning of April and the end of July 2021, 310 samples of frozen, breaded or battered chicken products containing either raw or partly cooked chicken, were collected using representative sampling of retailers in England, Wales, Scotland and Northern Ireland based on market share data. Samples included domestically produced and imported chicken products and were tested for E. coli (including extended-spectrum beta-lactamase (ESBL)-producing, colistin-resistant and carbapenem-resistant E. coli) and Salmonella spp. One isolate of each bacterial type from each contaminated sample was randomly selected for additional AMR testing to determine the minimum inhibitory concentration (MIC) for a range of antimicrobials. More detailed analysis based on Whole Genome Sequencing (WGS) data was used to further characterise Salmonella spp. isolates and allow the identification of potential links with human isolates. Salmonella spp. were detected in 5 (1.6%) of the 310 samples and identified as Salmonella Infantis (in three samples) and S. Java (in two samples). One of the S. Infantis isolates fell into the same genetic cluster as S. Infantis isolates from three recent human cases of infection; the second fell into another cluster containing two recent cases of infection. Countries of origin recorded on the packaging of the five Salmonella contaminated samples were Hungary (n=1), Ireland (n=2) and the UK (n=2). One S. Infantis isolate was multi-drug resistant (i.e. resistant to three different classes of antimicrobials), while the other Salmonella isolates were each resistant to at least one of the classes of antimicrobials tested. E. coli was detected in 113 samples (36.4%), with counts ranging from <3 to >1100 MPN (Most Probable Number)/g. Almost half of the E. coli isolates (44.5%) were susceptible to all antimicrobials tested. Multi-drug resistance was detected in 20.0% of E. coli isolates. E. coli isolates demonstrating the ESBL (but not AmpC) phenotype were detected in 15 of the 310 samples (4.8%) and the AmpC phenotype alone was detected in two of the 310 samples (0.6%) of chicken samples. Polymerase Chain Reaction (PCR) testing showed that five of the 15 (33.3%) ESBL-producing E. coli carried blaCTX-M genes (CTX-M-1, CTX-M-55 or CTX-M-15), which confer resistance to third generation cephalosporin antimicrobials. One E. coli isolate demonstrated resistance to colistin and was found to possess the mcr-1 gene. The five Salmonella-positive samples recovered from this study, and 20 similar Salmonella-positive samples from a previous UKHSA (2020/2021) study (which had been stored frozen), were subjected to the cooking procedures described on the sample product packaging for fan assisted ovens. No Salmonella were detected in any of these 25 samples after cooking. The current survey provides evidence of the presence of Salmonella in frozen, breaded and battered chicken products in the UK food chain, although at a considerably lower incidence than reported in an earlier (2020/2021) study carried out by PHE/UKHSA as part of an outbreak investigation where Salmonella prevalence was found to be 8.8%. The current survey also provides data on the prevalence of specified AMR bacteria found in the tested chicken products on retail sale in the UK. It will contribute to monitoring trends in AMR prevalence over time within the UK, support comparisons with data from other countries, and provide a baseline against which to monitor the impact of future interventions. While AMR activity was observed in some of the E. coli and Salmonella spp. examined in this study, the risk of acquiring AMR bacteria from consumption of these processed chicken products is low if the products are cooked thoroughly and handled hygienically.