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Sample records for attenuated salmonella choleraesuis-mediated

  1. 9 CFR 113.122 - Salmonella Choleraesuis Bacterin.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Choleraesuis Bacterin. 113... REQUIREMENTS Inactivated Bacterial Products § 113.122 Salmonella Choleraesuis Bacterin. Salmonella Choleraesuis Bacterin shall be prepared from a culture of Salmonella choleraesuis which has been inactivated and is...

  2. Effects of L-arabinose efflux on λ Red recombination-mediated gene knockout in multiple-antimicrobial-resistant Salmonella enterica serovar Choleraesuis.

    Science.gov (United States)

    Liao, Shi-Wei; Lee, Jen-Jie; Ptak, Christopher P; Wu, Ying-Chen; Hsuan, Shih-Ling; Kuo, Chih-Jung; Chen, Ter-Hsin

    2018-03-01

    In this study, six swine-derived multiple-antimicrobial-resistant (MAR) strains of Salmonella Choleraesuis (S. Choleraesuis) were demonstrated to possess higher efflux pump activity than the wild-type (WT). L-Arabinose, a common inducer for gene expression, modulated S. Choleraesuis efflux pump activity in a dose-dependent manner. At low L-arabinose concentrations, increasing L-arabinose led to a corresponding increase in fluorophore efflux, while at higher L-arabinose concentrations, increasing L-arabinose decreased fluorophore efflux activity. The WT S. Choleraesuis that lacks TolC (ΔtolC), an efflux protein associated with bacterial antibiotic resistance and virulence, was demonstrated to possess a significantly reduced ability to extrude L-arabinose. Further, due to the rapid export of L-arabinose, an efficient method for recombination-mediated gene knockout, the L-arabinose-inducible bacteriophage λ Red recombinase system, has a reduced recombination frequency (~ 12.5%) in clinically isolated MAR Salmonella strains. An increased recombination frequency (up to 60%) can be achieved using a higher concentration of L-arabinose (fivefold) for genetic manipulation and functional analysis for MAR Salmonella using the λ Red system. The study suggests that L-arabinose serves not only as an inducer of the TolC-dependent efflux system but also acts as a competitive substrate of the efflux system. In addition, understanding the TolC-dependent efflux of L-arabinose should facilitate the optimization of L-arabinose induction in strains with high efflux activity.

  3. [Immunogenicity of attenuated Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae in mice].

    Science.gov (United States)

    Ma, Fengying; Zou, Haoyong; He, Qigai

    2011-09-01

    The study was carried out to construct and characterize Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae and to test its immunogenicity in mice. We made p36, p46, p65 and p97R1-Nrdf, the main immunogenic genes of Mycoplasma hyopneumoniae, to insert into the prokaryotic expression plasmid pYA3493. Then these recombinant plasmids and pYA3493 were electroporated into C500 asd-mutant, resulting in the recombinant Salmonella choleraesuis vaccine strains C36 (pYA-36), C46 (pYA-46), C65 (pYA-65), C97R1-Nrdf(pYA-97R1-Nrdf) and CpYA(pYA3493). We characterized these recombinant Salmonella choleraesuis vaccine strains and tested the immunogenicity in mice by intramuscular injection or orally immunized. The results of the immunogenicity in mice indicated that the group orally immunized with C36, C46, C65, C97R1-Nrdf showed significantly higher Mycoplasma pneumoniae antibody than both the group orally immunized with C36, C46, C65 and the group intramuscular injected with the Mycoplasma hyopneumoniae bacterin (M + PAC) (P Mycoplasma hyopneumoniae bacterin (M + PAC) (P 0.05). The highest level of IL-4 was found in the group orally immunized with C36, C46, C65; higher levels of IL-4 was observed in the group orally immunized with C36, C46, C65, C97R1-Nrdf than the group injected with the Mycoplasma hyopneumoniae bacterin (M + PAC); and the lowest IL-4 level was found in the group injected with C36, C46, C65. There were no significant differences among them (P > 0.05). The Mycoplasma pneumoniae antibody, IFN-gamma or IL-4 production of the each group was obviously higher than the control group (P Mycoplasma hyopneumoniae which has immunogenicity in mice especially by intramuscular injection could probably serve as a vaccine against mycoplasmal pneumonia of swine.

  4. Salmonella enterica serovar Choleraesuis vector delivering SaoA antigen confers protection against Streptococcus suis serotypes 2 and 7 in mice and pigs.

    Science.gov (United States)

    Li, Yu-An; Ji, Zhenying; Wang, Xiaobo; Wang, Shifeng; Shi, Huoying

    2017-12-21

    Streptococcus suis is one of the major pathogens that cause economic losses in the swine industry worldwide. However, current bacterins only provide limited prophylactic protection in the field. An ideal vaccine against S. suis should protect pigs against the clinical diseases caused by multiple serotypes, or at least protect against the dominant serotype in a given geographic region. A new recombinant Salmonella enterica serotype Choleraesuis vaccine vector, rSC0011, that is based on the regulated delayed attenuation system and regulated delayed antigen synthesis system, was developed recently. In this study, an improved recombinant attenuated Salmonella Choleraesuis vector, rSC0016, was developed by incorporating a sopB mutation to ensure adequate safety and maximal immunogenicity. In the spleens of mice, rSC0016 colonized less than rSC0011. rSC0016 and rSC0011 colonized similarly in Peyer's patches of mice. The recombinant vaccine rSC0016(pS-SaoA) induced stronger cellular, humoral, and mucosal immune responses in mice and swine against SaoA, a conserved surface protein that is present in many S. suis serotypes, than did rSC0011(pS-SaoA) without sopB or rSC0018(pS-SaoA), which is an avirulent, chemically attenuated vaccine strain. rSC0016(pS-SaoA) provided 100% protection against S. suis serotype 2 in mice and pigs, and full cross-protection against SS7 in pigs. This new vaccine vector provides a foundation for the development of a universal vaccine against multiple serotypes of S. suis in pigs.

  5. Attenuated Salmonella choleraesuis-mediated RNAi targeted to conserved regions against foot-and-mouth disease virus in guinea pigs and swine

    Science.gov (United States)

    Cong, Wei; Jin, Hong; Jiang, Chengda; Yan, Weiyao; Liu, Mingqiu; Chen, Jiulian; Zuo, Xiaoping; Zheng, Zhaoxin

    2010-01-01

    In this study, specific sequences within three genes (3D, VP4 and 2B) of the foot-and-mouth disease virus (FMDV) genome were determined to be effective RNAi targets. These sequences are highly conserved among different serotype viruses based on sequence analysis. Small interfering RNA (siRNA)-expressing plasmids (p3D-NT19, p3D-NT56, pVP4-NT19, pVP4-NT65 and p2B-NT25) were constructed to express siRNA targeting 3D, VP4 and 2B, respectively. The antiviral potential of these siRNA for various FMDV isolates was investigated in baby hamster kidney (BHK-21) cells and suckling mice. The results show that these siRNA inhibited virus yield 10- to 300-fold for different FMDV isolates of serotype O and serotype Asia I at 48 h post infection in BHK-21 cells compared to control cells. In suckling mice, p3D-NT56 and p2B-NT25 delayed the death of mice. Twenty percent to 40% of the animals that received a single siRNA dose survived 5 days post infection with serotype O or serotype Asia I. We used an attenuated Salmonella choleraesuis (C500) vaccine strain, to carry the plasmid that expresses siRNA directed against the polymerase gene 3D (p3D-NT56) of FMDV. We used guinea pigs to evaluate the inhibitory effects of recombinant S. cho (p3D-NT56/S. cho) on FMDV infection. The results show that 80% of guinea pigs inoculated with 109 CFU of p3D-NT56/S. cho and challenged 36 h later with 50 ID50 of homologous FMDV were protected. We also measured the antiviral activity of p3D-NT56/S. cho in swine. The results indicate that 100% of the animals treated with 5 × 109 CFU of p3D-NT56/S. cho were protected in 9 days. PMID:20167192

  6. TolC is important for bacterial survival and oxidative stress response in Salmonella enterica serovar Choleraesuis in an acidic environment.

    Science.gov (United States)

    Lee, Jen-Jie; Wu, Ying-Chen; Kuo, Chih-Jung; Hsuan, Shih-Ling; Chen, Ter-Hsin

    2016-09-25

    The outer membrane protein TolC, which is one of the key components of several multidrug efflux pumps, is thought to be involved in various independent systems in Enterobacteriaceae. Since the acidic environment of the stomach is an important protection barrier against foodborne pathogen infections in hosts, we evaluated whether TolC played a role in the acid tolerance of Salmonella enterica serovar Choleraesuis. Comparison of the acid tolerance of the tolC mutant and the parental wild-type strain showed that the absence of TolC limits the ability of Salmonella to sustain life under extreme acidic conditions. Additionally, the mutant exhibited morphological changes during growth in an acidic medium, leading to the conflicting results of cell viability measured by spectrophotometry and colony-forming unit counting. Reverse-transcriptional-PCR analysis indicated that acid-related molecules, apparatus, or enzymes and oxidation-induced factors were significantly affected by the acidic environment in the null-tolC mutant. The elongated cellular morphology was restored by adding antioxidants to the culture medium. Furthermore, we found that increased cellular antioxidative activity provides an overlapping protection against acid killing, demonstrating the complexity of the bacterial acid stress response. Our findings reinforce the multifunctional characteristics of TolC in acid tolerance or oxidative stress resistance and support the correlative protection mechanism between oxygen- and acid-mediated stress responses in Salmonella enterica serovar Choleraesuis. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. An outbreak of Salmonella enterica serotype Choleraesuis in goitered gazelle (Gazella subgutrosa subgutrosa) and a Malayan tapir (Tapirus indicus).

    Science.gov (United States)

    Wolf, Tiffany M; Wünschmann, Arno; Morningstar-Shaw, Brenda; Pantlin, Gayle C; Rasmussen, James M; Thompson, Rachel L

    2011-12-01

    An outbreak of Salmonella enterica serotype Choleraesuis enteritis occurred in two juvenile goitered gazelles and an adult Malayan tapir over a period of 5 wk at the Minnesota Zoo. Diagnosis was made postmortem on one gazelle and one tapir, and a second gazelle was diagnosed via fecal culture. The death of the tapir was attributed to S. enterica serovar Choleraesuis septicemia, while salmonellosis was considered to be a contributing factor besides ostertagiasis for the death of one goitered gazelle and for the diarrhea of another goitered gazelle. A third gazelle became ill in the same time period, but Salmonella infection was not confirmed by culture. All exhibited the clinical signs of profuse, watery diarrhea. The gazelles developed a protein-losing enteropathy, and the tapir showed signs of sepsis and endotoxemia. Serotyping and pulsed-field gel electrophoresis revealed the Salmonella isolates to be indistinguishable from each other. One year prior to this outbreak, Salmonella sp. was cultured from a Visayan warty pig (Sus cebifrons) housed in the same building as the tapir. After further investigation into the outbreak, spread of this pathogen was speculated to be associated with human movement across animal areas.

  8. Antimicrobial Resistance and Molecular Investigation of H2S-Negative Salmonella enterica subsp. enterica serovar Choleraesuis Isolates in China.

    Directory of Open Access Journals (Sweden)

    Jing Xie

    Full Text Available Salmonella enterica subsp. enterica serovar Choleraesuis is a highly invasive pathogen of swine that frequently causes serious outbreaks, in particular in Asia, and can also cause severe invasive disease in humans. In this study, 21 S. Choleraesuis isolates, detected from 21 patients with diarrhea in China between 2010 and 2011, were found to include 19 H2S-negative S. Choleraesuis isolates and two H2S-positive isolates. This is the first report of H2S-negative S. Choleraesuis isolated from humans. The majority of H2S-negative isolates exhibited high resistance to ampicillin, chloramphenicol, gentamicin, tetracycline, ticarcillin, and trimethoprim-sulfamethoxazole, but only six isolates were resistant to norfloxacin. In contrast, all of the isolates were sensitive to cephalosporins. Fifteen isolates were found to be multidrug resistant. In norfloxacin-resistant isolates, we detected mutations in the gyrA and parC genes and identified two new mutations in the parC gene. Pulsed-field gel electrophoresis (PFGE, multilocus sequence typing (MLST, and clustered regularly interspaced short palindromic repeat (CRISPR analysis were employed to investigate the genetic relatedness of H2S-negative and H2S-positive S. Choleraesuis isolates. PFGE revealed two groups, with all 19 H2S-negative S. Choleraesuis isolates belonging to Group I and H2S-positive isolates belonging to Group II. By MLST analysis, the H2S-negative isolates were all found to belong to ST68 and H2S-positive isolates belong to ST145. By CRISPR analysis, no significant differences in CRISPR 1 were detected; however, one H2S-negative isolate was found to contain three new spacers in CRISPR 2. All 19 H2S-negative isolates also possessed a frame-shift mutation at position 760 of phsA gene compared with H2S-positive isolates, which may be responsible for the H2S-negative phenotype. Moreover, the 19 H2S-negative isolates have similar PFGE patterns and same mutation site in the phsA gene, these

  9. Antimicrobial Resistance and Molecular Investigation of H2S-Negative Salmonella enterica subsp. enterica serovar Choleraesuis Isolates in China.

    Science.gov (United States)

    Xie, Jing; Yi, Shengjie; Zhu, Jiangong; Li, Peng; Liang, Beibei; Li, Hao; Yang, Xiaoxia; Wang, Ligui; Hao, Rongzhang; Jia, Leili; Wu, Zhihao; Qiu, Shaofu; Song, Hongbin

    2015-01-01

    Salmonella enterica subsp. enterica serovar Choleraesuis is a highly invasive pathogen of swine that frequently causes serious outbreaks, in particular in Asia, and can also cause severe invasive disease in humans. In this study, 21 S. Choleraesuis isolates, detected from 21 patients with diarrhea in China between 2010 and 2011, were found to include 19 H2S-negative S. Choleraesuis isolates and two H2S-positive isolates. This is the first report of H2S-negative S. Choleraesuis isolated from humans. The majority of H2S-negative isolates exhibited high resistance to ampicillin, chloramphenicol, gentamicin, tetracycline, ticarcillin, and trimethoprim-sulfamethoxazole, but only six isolates were resistant to norfloxacin. In contrast, all of the isolates were sensitive to cephalosporins. Fifteen isolates were found to be multidrug resistant. In norfloxacin-resistant isolates, we detected mutations in the gyrA and parC genes and identified two new mutations in the parC gene. Pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and clustered regularly interspaced short palindromic repeat (CRISPR) analysis were employed to investigate the genetic relatedness of H2S-negative and H2S-positive S. Choleraesuis isolates. PFGE revealed two groups, with all 19 H2S-negative S. Choleraesuis isolates belonging to Group I and H2S-positive isolates belonging to Group II. By MLST analysis, the H2S-negative isolates were all found to belong to ST68 and H2S-positive isolates belong to ST145. By CRISPR analysis, no significant differences in CRISPR 1 were detected; however, one H2S-negative isolate was found to contain three new spacers in CRISPR 2. All 19 H2S-negative isolates also possessed a frame-shift mutation at position 760 of phsA gene compared with H2S-positive isolates, which may be responsible for the H2S-negative phenotype. Moreover, the 19 H2S-negative isolates have similar PFGE patterns and same mutation site in the phsA gene, these results indicated

  10. Oral vaccination with attenuated Salmonella choleraesuis C500 ...

    African Journals Online (AJOL)

    user

    Marshall, 1983), and well known as the major gastro- duodenal ... The CagA is encoded in a pathogenicity island known as 'Cag PAI' and is .... HindIII to release the CagA fragment. The purified .... vaccine strain attenuated by chemical methods, which is .... pylori antigens is achieved using a non-toxic mutant of E. coli heat-.

  11. Attenuation of 10 MeV electron beam energy to achieve low doses does not affect Salmonella spp. inactivation kinetics

    International Nuclear Information System (INIS)

    Hieke, Anne-Sophie Charlotte; Pillai, Suresh D.

    2015-01-01

    The effect of attenuating the energy of a 10 MeV electron beam on Salmonella inactivation kinetics was investigated. No statistically significant differences were observed between the D 10 values of either Salmonella 4,[5],12:i:- or a Salmonella cocktail (S. 4,[5],12:i:-, Salmonella Heidelberg, Salmonella Newport, Salmonella Typhimurium, Salmonella) when irradiated with either a non-attenuated 10 MeV eBeam or an attenuated 10 MeV eBeam (~2.9±0.22 MeV). The results show that attenuating the energy of a 10 MeV eBeam to achieve low doses does not affect the inactivation kinetics of Salmonella spp. when compared to direct 10 MeV eBeam irradiation. - Highlights: • 10 MeV eBeam energy was attenuated to 2.9±0.22 MeV using HDPE sheets. • Attenuation of eBeam energy does not affect the inactivation kinetics of Salmonella. • Microbial inactivation is independent of eBeam energy in the range of 3–10 MeV

  12. Oral vaccination with attenuated Salmonella choleraesuis C500 ...

    African Journals Online (AJOL)

    Helicobacter pylori are well known as the major gastro-duodenal pathogen of peptic ulcer disease and gastric cancer. Recombinant H. pylori vaccine comprising a single subunit antigen can only induce immune response with limited protection efficiency. Development of oral vaccine would be a new effective strategy for the ...

  13. Evolution of Salmonella enterica virulence via point mutations in the fimbrial adhesin.

    Directory of Open Access Journals (Sweden)

    Dagmara I Kisiela

    Full Text Available Whereas the majority of pathogenic Salmonella serovars are capable of infecting many different animal species, typically producing a self-limited gastroenteritis, serovars with narrow host-specificity exhibit increased virulence and their infections frequently result in fatal systemic diseases. In our study, a genetic and functional analysis of the mannose-specific type 1 fimbrial adhesin FimH from a variety of serovars of Salmonella enterica revealed that specific mutant variants of FimH are common in host-adapted (systemically invasive serovars. We have found that while the low-binding shear-dependent phenotype of the adhesin is preserved in broad host-range (usually systemically non-invasive Salmonella, the majority of host-adapted serovars express FimH variants with one of two alternative phenotypes: a significantly increased binding to mannose (as in S. Typhi, S. Paratyphi C, S. Dublin and some isolates of S. Choleraesuis, or complete loss of the mannose-binding activity (as in S. Paratyphi B, S. Choleraesuis and S. Gallinarum. The functional diversification of FimH in host-adapted Salmonella results from recently acquired structural mutations. Many of the mutations are of a convergent nature indicative of strong positive selection. The high-binding phenotype of FimH that leads to increased bacterial adhesiveness to and invasiveness of epithelial cells and macrophages usually precedes acquisition of the non-binding phenotype. Collectively these observations suggest that activation or inactivation of mannose-specific adhesive properties in different systemically invasive serovars of Salmonella reflects their dynamic trajectories of adaptation to a life style in specific hosts. In conclusion, our study demonstrates that point mutations are the target of positive selection and, in addition to horizontal gene transfer and genome degradation events, can contribute to the differential pathoadaptive evolution of Salmonella.

  14. aroA-Deficient Salmonella enterica Serovar Typhimurium Is More Than a Metabolically Attenuated Mutant

    Science.gov (United States)

    Frahm, Michael; Kocijancic, Dino; Rohde, Manfred; Eckweiler, Denitsa; Bielecka, Agata; Bueno, Emilio; Cava, Felipe; Abraham, Wolf-Rainer; Curtiss, Roy; Häussler, Susanne; Erhardt, Marc; Weiss, Siegfried

    2016-01-01

    ABSTRACT Recombinant attenuated Salmonella enterica serovar Typhimurium strains are believed to act as powerful live vaccine carriers that are able to elicit protection against various pathogens. Auxotrophic mutations, such as a deletion of aroA, are commonly introduced into such bacteria for attenuation without incapacitating immunostimulation. In this study, we describe the surprising finding that deletion of aroA dramatically increased the virulence of attenuated Salmonella in mouse models. Mutant bacteria lacking aroA elicited increased levels of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α) after systemic application. A detailed genetic and phenotypic characterization in combination with transcriptomic and metabolic profiling demonstrated that ΔaroA mutants display pleiotropic alterations in cellular physiology and lipid and amino acid metabolism, as well as increased sensitivity to penicillin, complement, and phagocytic uptake. In concert with other immunomodulating mutations, deletion of aroA affected flagellin phase variation and gene expression of the virulence-associated genes arnT and ansB. Finally, ΔaroA strains displayed significantly improved tumor therapeutic activity. These results highlight the importance of a functional shikimate pathway to control homeostatic bacterial physiology. They further highlight the great potential of ΔaroA-attenuated Salmonella for the development of vaccines and cancer therapies with important implications for host-pathogen interactions and translational medicine. PMID:27601574

  15. Multilocus sequence typing as a replacement for serotyping in Salmonella enterica.

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    Mark Achtman

    Full Text Available Salmonella enterica subspecies enterica is traditionally subdivided into serovars by serological and nutritional characteristics. We used Multilocus Sequence Typing (MLST to assign 4,257 isolates from 554 serovars to 1092 sequence types (STs. The majority of the isolates and many STs were grouped into 138 genetically closely related clusters called eBurstGroups (eBGs. Many eBGs correspond to a serovar, for example most Typhimurium are in eBG1 and most Enteritidis are in eBG4, but many eBGs contained more than one serovar. Furthermore, most serovars were polyphyletic and are distributed across multiple unrelated eBGs. Thus, serovar designations confounded genetically unrelated isolates and failed to recognize natural evolutionary groupings. An inability of serotyping to correctly group isolates was most apparent for Paratyphi B and its variant Java. Most Paratyphi B were included within a sub-cluster of STs belonging to eBG5, which also encompasses a separate sub-cluster of Java STs. However, diphasic Java variants were also found in two other eBGs and monophasic Java variants were in four other eBGs or STs, one of which is in subspecies salamae and a second of which includes isolates assigned to Enteritidis, Dublin and monophasic Paratyphi B. Similarly, Choleraesuis was found in eBG6 and is closely related to Paratyphi C, which is in eBG20. However, Choleraesuis var. Decatur consists of isolates from seven other, unrelated eBGs or STs. The serological assignment of these Decatur isolates to Choleraesuis likely reflects lateral gene transfer of flagellar genes between unrelated bacteria plus purifying selection. By confounding multiple evolutionary groups, serotyping can be misleading about the disease potential of S. enterica. Unlike serotyping, MLST recognizes evolutionary groupings and we recommend that Salmonella classification by serotyping should be replaced by MLST or its equivalents.

  16. Evaluation of a novel enzyme-linked immunosorbent assay for detection of antibodies against Salmonella, employing a stable coating of lipopolysaccharide-derived antigens covalently attached to polystyrene microwells

    DEFF Research Database (Denmark)

    Wiuff, C.; Jauho, E. S.; Stryhn, H.

    2000-01-01

    to microtiter polystyrene plates by ultraviolet irradiation. Both polysaccharide antigens could be coupled simultaneously to the same microtiter plate. The coated surface was used in indirect ELISA for the determination of serum antibodies from pigs infected with bacteria of the two Salmonella groups and from......Polysaccharides derived from Salmonella typhimurium lipopolysaccharide (LPS) representing the O-antigen factors 1, 4, 5, and 12 and the O-antigen factors 6 and 7 from Salmonella choleraesuis LPS were derivatized with the photoreactive compound anthraquinone and subsequently covalently coupled...

  17. Salmonella enterica serovar Typhimurium lacking hfq gene confers protective immunity against murine typhoid.

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    Uday Shankar Allam

    Full Text Available Salmonella enterica is an important enteric pathogen and its various serovars are involved in causing both systemic and intestinal diseases in humans and domestic animals. The emergence of multidrug-resistant strains of Salmonella leading to increased morbidity and mortality has further complicated its management. Live attenuated vaccines have been proven superior over killed or subunit vaccines due to their ability to induce protective immunity. Of the various strategies used for the generation of live attenuated vaccine strains, focus has gradually shifted towards manipulation of virulence regulator genes. Hfq is a RNA chaperon which mediates the binding of small RNAs to the mRNA and assists in post-transcriptional gene regulation in bacteria. In this study, we evaluated the efficacy of the Salmonella Typhimurium Δhfq strain as a candidate for live oral vaccine in murine model of typhoid fever. Salmonella hfq deletion mutant is highly attenuated in cell culture and animal model implying a significant role of Hfq in bacterial virulence. Oral immunization with the Salmonella hfq deletion mutant efficiently protects mice against subsequent oral challenge with virulent strain of Salmonella Typhimurium. Moreover, protection was induced upon both multiple as well as single dose of immunizations. The vaccine strain appears to be safe for use in pregnant mice and the protection is mediated by the increase in the number of CD4(+ T lymphocytes upon vaccination. The levels of serum IgG and secretory-IgA in intestinal washes specific to lipopolysaccharide and outer membrane protein were significantly increased upon vaccination. Furthermore, hfq deletion mutant showed enhanced antigen presentation by dendritic cells compared to the wild type strain. Taken together, the studies in murine immunization model suggest that the Salmonella hfq deletion mutant can be a novel live oral vaccine candidate.

  18. An association of genotypes and antimicrobial resistance patterns among Salmonella isolates from pigs and humans in Taiwan.

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    Hung-Chih Kuo

    Full Text Available We collected 110 Salmonella enterica isolates from sick pigs and determined their serotypes, genotypes using pulsed-field gel electrophoresis (PFGE, and antimicrobial susceptibility to 12 antimicrobials and compared the data with a collection of 18,280 isolates obtained from humans. The pig isolates fell into 12 common serovars for human salmonellosis in Taiwan; S. Typhimurium, S. Choleraesuis, S. Derby, S. Livingstone, and S. Schwarzengrund were the 5 most common serovars and accounted for a total of 84% of the collection. Of the 110 isolates, 106 (96% were multidrug resistant (MDR and 48 (44% had PFGE patterns found in human isolates. S. Typhimurium, S. Choleraesuis, and S. Schwarzengrund were among the most highly resistant serovars. The majority of the 3 serovars were resistant to 8-11 of the tested antimicrobials. The isolates from pigs and humans sharing a common PFGE pattern displayed identical or very similar resistance patterns and Salmonella strains that caused severe infection in pigs were also capable of causing infections in humans. The results indicate that pigs are one of the major reservoirs to human salmonellosis in Taiwan. Almost all of the pig isolates were MDR, which highlights the necessity of strictly regulating the use of antimicrobials in the agriculture sector in Taiwan.

  19. An association of genotypes and antimicrobial resistance patterns among Salmonella isolates from pigs and humans in Taiwan.

    Science.gov (United States)

    Kuo, Hung-Chih; Lauderdale, Tsai-Ling; Lo, Dan-Yuan; Chen, Chiou-Lin; Chen, Pei-Chen; Liang, Shiu-Yun; Kuo, Jung-Che; Liao, Ying-Shu; Liao, Chun-Hsing; Tsao, Chi-Sen; Chiou, Chien-Shun

    2014-01-01

    We collected 110 Salmonella enterica isolates from sick pigs and determined their serotypes, genotypes using pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility to 12 antimicrobials and compared the data with a collection of 18,280 isolates obtained from humans. The pig isolates fell into 12 common serovars for human salmonellosis in Taiwan; S. Typhimurium, S. Choleraesuis, S. Derby, S. Livingstone, and S. Schwarzengrund were the 5 most common serovars and accounted for a total of 84% of the collection. Of the 110 isolates, 106 (96%) were multidrug resistant (MDR) and 48 (44%) had PFGE patterns found in human isolates. S. Typhimurium, S. Choleraesuis, and S. Schwarzengrund were among the most highly resistant serovars. The majority of the 3 serovars were resistant to 8-11 of the tested antimicrobials. The isolates from pigs and humans sharing a common PFGE pattern displayed identical or very similar resistance patterns and Salmonella strains that caused severe infection in pigs were also capable of causing infections in humans. The results indicate that pigs are one of the major reservoirs to human salmonellosis in Taiwan. Almost all of the pig isolates were MDR, which highlights the necessity of strictly regulating the use of antimicrobials in the agriculture sector in Taiwan.

  20. Occurrence of extended-spectrum and AmpC β-lactamases in multiple drug resistant Salmonella isolates from clinical samples in Lagos, Nigeria

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    Akinyemi KO

    2017-01-01

    Full Text Available KO Akinyemi,1 Bamidele Abiodun Iwalokun,2 Akeeb O Bola Oyefolu,1 CO Fakorede1 1Department of Microbiology, Lagos State University, Ojo, 2Molecular Biology and Biotechnology Division, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria Purpose: Salmonella spp. are important foodborne pathogens exhibiting increasing resistance to antimicrobial drugs. Resistance to broad-spectrum β-lactams, mediated by extended-spectrum β-lactamase (ESBL and AmpC β-lactamase enzymes is fast spreading and has had negative impacts on the clinical outcomes, particularly on third-generation cephalosporins. This study investigated the carriage of AmpC gene among multidrug-resistant Salmonella spp. from Lagos, Nigeria. Methods: Forty Salmonella spp. from clinical samples (S. typhi = 13; S. typhimurium = 10; S. enteritidis = 8; S. choleraesuis = 5; S. paratyphi = 4 were subjected to in vitro susceptibility test by disk diffusion methods. Isolates that were resistant to cefoxitin and third-generation cephalosporins were screened for ESBL (Double Disk Synergy Test Method and AmpC enzyme (AmpC disk test production. Detection of AmpC fox gene was carried out by polymerase chain reaction. Results: Thirty-two (80% of the Salmonella isolates were cefoxitin resistant. Plasmid-mediated AmpC β-lactamase and ESBL enzymes were recorded in 10/40 (25% and 16/40 (40% of the Salmonella isolates, respectively. Specifically, 16/40 (40% of the Salmonella isolates possessed 380 bp AmpC fox gene, with the highest occurrence found in S. typhi strains (43.8% followed by S. typhimurium (25%. There was no AmpC fox gene detected in S. paratyphi strains. Interestingly, coproduction of enzymes occurred in some of the isolates, raising fears of resistance to a multitude of antibiotics in the treatment of bacterial infections. Conclusion: Emergence of AmpC β-lactamase–producing Salmonella isolates in our environment was recorded for the first time, raising concern on increased

  1. Oral Salmonella: malaria circumsporozoite recombinants induce specific CD8+ cytotoxic T cells

    OpenAIRE

    1990-01-01

    Oral immunization with an attenuated Salmonella typhimurium recombinant containing the full-length Plasmodium berghei circumsporozoite (CS) gene induces protective immunity against P. berghei sporozoite challenge in the absence of antibody. We found that this immunity was mediated through the induction of specific CD8+ T cells since in vivo elimination of CD8+ cells abrogated protection. In vitro studies revealed that this Salmonella-P. berghei CS recombinant induced class I- restricted CD8+ ...

  2. Salmonella-mediated cancer therapy: Roles and potential

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Vu Hong [Dept. of Experimental TherapeuticsBeckman Research Institute of City of Hope, Duarte (United States); Min, Jung Joon [Dept. of Nuclear MedicineChonnam National University Medical School, Gwangju (Korea, Republic of)

    2017-06-15

    The use of bacteria for cancer therapy, which was proposed many years ago, was not recognized as a potential therapeutic strategy until recently. Technological advances and updated knowledge have enabled the genetic engineering of bacteria for their safe and effective application in the treatment of cancer. The efficacy of radiotherapy depends mainly on tissue oxygen levels, and low oxygen concentrations in necrotic and hypoxic regions are a common cause of treatment failure. In addition, the distribution of a drug is important for the therapeutic effect of chemotherapy, and the poor vasculature in tumors impairs drug delivery, limiting the efficacy of a drug, especially in necrotic and hypoxic regions. Bacteria-mediated cancer therapy (BMCT) relies on facultative anaerobes that can survive in well or poorly oxygenated regions, and it therefore improves the therapeutic efficacy drug distribution throughout the tumor mass. Since the mid-1990s, the number of published bacterial therapy papers has increased rapidly, with a doubling time of 2.5 years in which the use of Salmonella increased significantly. BMCT is being reevaluated to overcome some of the drawbacks of conventional therapies. This review focuses on Salmonella-mediated cancer therapy as the most widely used type of BMCT.{sub 2}.

  3. Salmonella-mediated cancer therapy: Roles and potential

    International Nuclear Information System (INIS)

    Nguyen, Vu Hong; Min, Jung Joon

    2017-01-01

    The use of bacteria for cancer therapy, which was proposed many years ago, was not recognized as a potential therapeutic strategy until recently. Technological advances and updated knowledge have enabled the genetic engineering of bacteria for their safe and effective application in the treatment of cancer. The efficacy of radiotherapy depends mainly on tissue oxygen levels, and low oxygen concentrations in necrotic and hypoxic regions are a common cause of treatment failure. In addition, the distribution of a drug is important for the therapeutic effect of chemotherapy, and the poor vasculature in tumors impairs drug delivery, limiting the efficacy of a drug, especially in necrotic and hypoxic regions. Bacteria-mediated cancer therapy (BMCT) relies on facultative anaerobes that can survive in well or poorly oxygenated regions, and it therefore improves the therapeutic efficacy drug distribution throughout the tumor mass. Since the mid-1990s, the number of published bacterial therapy papers has increased rapidly, with a doubling time of 2.5 years in which the use of Salmonella increased significantly. BMCT is being reevaluated to overcome some of the drawbacks of conventional therapies. This review focuses on Salmonella-mediated cancer therapy as the most widely used type of BMCT._2

  4. CHARACTERIZATION OF SALMONELLA SPECIES FROM WATER BODIES IN DAR-ES-SALAAM CITY, TANZANIA

    Directory of Open Access Journals (Sweden)

    Eliningaya Kweka

    2013-03-01

    Full Text Available Background: Water-borne diseases are the most common cause of illness and death among the poor population from developing countries. The majority of the people are inadequately aware that aquatic environment is a major source of salmonellosis. Dar es Salaam city is among the cities with most of its population live in squatter. Typhoid fever ranks second with 14.3% of all notifiable disease cases in the city. The city experience water scarcity which forces water wells and rivers to become the main sources of water for domestic use and livestock. This study therefore, characterized Salmonella strains from different water bodies of city as possible sources for enteric diseases endemicity. Methods: The Salmonella Chromogenic Agar (SC Agar and Kligler Iron Agar (KIA media were used for isolation and enumeration of the strains. The inoculated cultures were incubated at 370C for 24 hours. Salmonella colonies were confirmed by magenta colorations and hydrogen sulfide production on SC Agar and KIA Agar, respectively. The Analytical Profile Index 20 Enterobacteriaceae kit (API 20E kit was used to identify Salmonella species. Results: Based on the API 20E kit, the identified Salmonella species from different water bodies were Salmonella ser. paratyphi A (96.9%, Salmonella cholelaesuis spp choleraesuis (99.5% and Salmonella typhi (99.9%. Conclusion: This study shows that shallow wells and rivers which are mainly used by the city dwellers were highly contaminated with Salmonella and were more contaminated than deep wells and marine water bodies. This warrants further investigation on the disease mapping in the urban and peri-urban areas.

  5. Protection from radiation injury through oral administration of PF4 gene carried by attenuated salmonella

    International Nuclear Information System (INIS)

    Zhao Lihua; Liu Bin; Yu Xiaofei; Zhang Lei; Han Zhongchao

    2005-01-01

    Objective: To investigate the in vivo radiation protection effect of PF4 by oral administration of attenuated salmonella as the carrier in mice. Methods: The eukaryotic vector pIRES2-EGFP-carried PF4 gene was transferred into an aroA-autotrophic mutant of salmonella typhimurium (SL3261), which was administered orally to BALBPc mice at 1x10 8 PFu once every interval three days. At 12 hours after the third oral administration the mice were subjected to a total body irradiation (TBI) of 700 cGy by a 60 Co source. The protective effect of SL3261/PF4 was determined by detection GFP ( green fluorescence protein) expression in tissues, peripheral blood count, culture of bone marrow colony-forming cells and survival time of mice. Results: Expression of GFP could be detected in the liver, spleen, intestine, kidney, peripheral blood and bone marrow. On days 7 and 14 after irradiation, Compared to controls, there were obvious differences in number of bone marrow mononuclear cells, CFU-GM (granulocyte-macrophage colony-forming unit ) and HPP-CFC (high proliferating potential-colony-forming cells) of mice treated with SL3261/PF4 (P<0.05) as well as prolongation of the survival time. Conclusion: These data demonstrate for the first time that PF4 protects mice from TBI injury and accelerates recovery of hematopoiesis by oral administration of attenuated salmonella carrying PF4 gene. (authors)

  6. Development of a flexible and potent hypoxia-inducible promoter for tumor-targeted gene expression in attenuated Salmonella

    NARCIS (Netherlands)

    Mengesha, Asferd; Dubois, Ludwig; Lambin, Philippe; Landuyt, Willy; Chiu, Roland K; Wouters, Bradly G; Theys, Jan

    To increase the potential of attenuated Salmonella as gene delivery vectors for cancer treatment, we developed a hypoxia-inducible promoter system to limit gene expression specifically to the tumor. This approach is envisaged to not only increase tumor specificity, but also to target those cells

  7. Plasmid-mediated quinolone resistance in Salmonella serotypes isolated from chicken carcasses in Turkey

    Directory of Open Access Journals (Sweden)

    Zafer Ata

    2014-01-01

    Full Text Available Quinolones have been extensively used for treatment of a variety of invasive and systemic infections of salmonellosis. Widespread use of these agents has been associated with the emergence and dissemination of quinolone-resistant pathogens. The quinolone resistance and plasmid-mediated quinolone resistance determinants (qnrA, qnrB, qnrS and aac(6’-Ib-cr of 85 Salmonella isolates from chicken carcasses were investigated in this study. Isolates were serotyped according to the Kauffman-White-Le Minor scheme, and broth microdilution method was used to determine quinolone resistance. Plasmid-mediated quinolone resistance genes were investigated by real-time PCR and positive results were confirmed by sequencing. Among the Salmonella isolates, 30/85 (35% and 18/85 (21% were found to be resistant to enrofloxacin (MIC ≥ 2 mg/ml, and danofloxacin (MIC ≥ 2 mg/ml, respectively. All the isolates were negative for qnrA, qnrB and aac(6’-Ib-cr genes, nevertheless 2% (S. Brandenburg and S. Dabou were positive for qnrS (qnrS1 determinant. This study is the first and unique investigating the plasmid- mediated quinolone resistance determinants of Salmonella isolated from chicken carcasses in Turkey.

  8. Characterization of Salmonella species from water bodies in Dar-Es-Salaam city, Tanzania

    Directory of Open Access Journals (Sweden)

    Eliningaya Kweka

    2013-01-01

    Full Text Available Background: Water-borne diseases are the most common cause of illness and death among the poor population from developing countries. The majority of the people are inadequately aware that aquatic environment is a major source of salmonellosis. Dar es Salaam city is among the cities with most of its population live in squatter. Typhoid fever ranks second with 14.3% of all notifiable disease cases in the city. The city experience water scarcity which forces water wells and rivers to become the main sources of water for domestic use and livestock. This study therefore, characterized Salmonella strains from different water bodies of city as possible sources for enteric diseases endemicity. Methods: The Salmonella Chromogenic Agar (SC Agar and Kligler Iron Agar (KIA media were used for isolation and enumeration of the strains. The inoculated cultures were incubated at 370C for 24 hours. Salmonella colonies were confirmed by magenta colorations and hydrogen sulfide production on SC Agar and KIA Agar, respectively. The Analytical Profile Index 20 Enterobacteriaceae kit (API 20E kit was used to identify Salmonella species. Results: Based on the API 20E kit, the  identified Salmonella species from different water bodies were Salmonella ser. paratyphi A (96.9%, Salmonella cholelaesuis spp choleraesuis (99.5% and Salmonella typhi (99.9%. Conclusion: This study shows that shallow wells and rivers which are mainly used by the city dwellers were highly contaminated with Salmonella and were more contaminated than deep wells and marine water bodies. This warrants further investigation on the disease mapping in the urban and peri-urban areas.

  9. Identification of a Plasmid-Mediated Quinolone Resistance Gene in Salmonella Isolates from Texas Dairy Farm Environmental Samples.

    Science.gov (United States)

    Cummings, K J; Rodriguez-Rivera, L D; Norman, K N; Ohta, N; Scott, H M

    2017-06-01

    A recent increase in plasmid-mediated quinolone resistance (PMQR) has been detected among Salmonella isolated from humans in the United States, and it is necessary to determine the sources of human infection. We had previously isolated Salmonella from dairy farm environmental samples collected in Texas, and isolates were tested for anti-microbial susceptibility. Two isolates, serotyped as Salmonella Muenster, showed the discordant pattern of nalidixic acid susceptibility and intermediate susceptibility to ciprofloxacin. For this project, whole-genome sequencing of both isolates was performed to detect genes associated with quinolone resistance. The plasmid-mediated qnrB19 gene and IncR plasmid type were identified in both isolates. To our knowledge, this is the first report of PMQR in Salmonella isolated from food animals or agricultural environments in the United States. © 2016 Blackwell Verlag GmbH.

  10. Use of Attenuated but Metabolically Competent Salmonella as a Probiotic To Prevent or Treat Salmonella Infection

    Science.gov (United States)

    Sabag-Daigle, Anice; Blunk, Henry M.; Gonzalez, Juan F.; Steidley, Brandi L.; Boyaka, Prosper N.

    2016-01-01

    Salmonella enterica is among the most burdensome of foodborne disease agents. There are over 2,600 serovars that cause a range of disease manifestations ranging from enterocolitis to typhoid fever. While there are two vaccines in use in humans to protect against typhoid fever, there are none that prevent enterocolitis. If vaccines preventing enterocolitis were to be developed, they would likely protect against only one or a few serovars. In this report, we tested the hypothesis that probiotic organisms could compete for the preferred nutrient sources of Salmonella and thus prevent or treat infection. To this end, we added the fra locus, which encodes a utilization pathway for the Salmonella-specific nutrient source fructose-asparagine (F-Asn), to the probiotic bacterium Escherichia coli Nissle 1917 (Nissle) to increase its ability to compete with Salmonella in mouse models. We also tested a metabolically competent, but avirulent, Salmonella enterica serovar Typhimurium mutant for its ability to compete with wild-type Salmonella. The modified Nissle strain became more virulent and less able to protect against Salmonella in some instances. On the other hand, the modified Salmonella strain was safe and effective in preventing infection with wild-type Salmonella. While we tested for efficacy only against Salmonella Typhimurium, the modified Salmonella strain may be able to compete metabolically with most, if not all, Salmonella serovars, representing a novel approach to control of this pathogen. PMID:27185789

  11. Engineering and preclinical evaluation of attenuated nontyphoidal Salmonella strains serving as live oral vaccines and as reagent strains.

    Science.gov (United States)

    Tennant, Sharon M; Wang, Jin-Yuan; Galen, James E; Simon, Raphael; Pasetti, Marcela F; Gat, Orit; Levine, Myron M

    2011-10-01

    While nontyphoidal Salmonella (NTS) has long been recognized as a cause of self-limited gastroenteritis, it is becoming increasingly evident that multiple-antibiotic-resistant strains are also emerging as important causes of invasive bacteremia and focal infections, resulting in hospitalizations and deaths. We have constructed attenuated Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Enteritidis strains that can serve as live oral vaccines and as "reagent strains" for subunit vaccine production in a safe and economical manner. Prototype attenuated vaccine strains CVD 1921 and CVD 1941, derived from the invasive wild-type strains S. Typhimurium I77 and S. Enteritidis R11, respectively, were constructed by deleting guaBA, encoding guanine biosynthesis, and clpP, encoding a master protease regulator. The clpP mutation resulted in a hyperflagellation phenotype. An additional deletion in fliD yielded reagent strains CVD 1923 and CVD 1943, respectively, which export flagellin monomers. Oral 50% lethal dose (LD₅₀) analyses showed that the NTS vaccine strains were all highly attenuated in mice. Oral immunization with CVD 1921 or CVD 1923 protected mice against lethal challenge with wild-type S. Typhimurium I77. Immunization with CVD 1941 but not CVD 1943 protected mice against lethal infection with S. Enteritidis R11. Immune responses induced by these strains included high levels of serum IgG anti-lipopolysaccharide (LPS) and anti-flagellum antibodies, with titers increasing progressively during the immunization schedule. Since S. Typhimurium and S. Enteritidis are the most common NTS serovars associated with invasive disease, these findings can pave the way for development of a highly effective, broad-spectrum vaccine against invasive NTS.

  12. Connexin 43 Gene Therapy Delivered by Polymer-Modified Salmonella in Murine Tumor Models

    Directory of Open Access Journals (Sweden)

    Wei-Kuang Wang

    2014-04-01

    Full Text Available The use of preferentially tumor-targeting bacteria as vectors is one of the most innovative approaches for the treatment of cancer. This method is based on the observation that some obligate or facultative anaerobic bacteria are capable of selectively multiplying in tumors and inhibiting their growth. Previously, we found that the tumor-targeting efficiency of Salmonella could be modulated by modifying the immune response to these bacteria by coating them with poly(allylamine hydrochloride (PAH, and these organisms are designated PAH-S.C. (S. choleraesuis. PAH can provide a useful platform for the chemical modification of Salmonella, perhaps by allowing a therapeutic gene to bind to tumor-targeting Salmonella. This study aimed to investigate the benefits of the use of PAH-S.C. for gene delivery. To evaluate this modulation, the invasion activity and gene transfer of DNA-PAH-S.C. were measured in vitro and in vivo. Treatment with PAH-S.C. carrying a tumor suppressor gene (connexin 43 resulted in inhibition of tumor growth, which suggested that tumor-targeted gene therapy using PAH-S.C. carrying a therapeutic gene could exert antitumor activities. This technique represents a promising strategy for the treatment of tumors.

  13. Vaccines against invasive Salmonella disease

    Science.gov (United States)

    MacLennan, Calman A; Martin, Laura B; Micoli, Francesca

    2014-01-01

    Though primarily enteric pathogens, Salmonellae are responsible for a considerable yet under-appreciated global burden of invasive disease. In South and South-East Asia, this manifests as enteric fever caused by serovars Typhi and Paratyphi A. In sub-Saharan Africa, a similar disease burden results from invasive nontyphoidal Salmonellae, principally serovars Typhimurium and Enteritidis. The existing Ty21a live-attenuated and Vi capsular polysaccharide vaccines target S. Typhi and are not effective in young children where the burden of invasive Salmonella disease is highest. After years of lack of investment in new Salmonella vaccines, recent times have seen increased interest in the area led by emerging-market manufacturers, global health vaccine institutes and academic partners. New glycoconjugate vaccines against S. Typhi are becoming available with similar vaccines against other invasive serovars in development. With other new vaccines under investigation, including live-attenuated, protein-based and GMMA vaccines, now is an exciting time for the Salmonella vaccine field. PMID:24804797

  14. LOOP-MEDIATED ISOTHERMAL AMPLIFICATION (LAMP) FOR THE DETECTION OF SALMONELLA SPP. ISOLATED FROM DIFFERENT FOOD TYPES

    OpenAIRE

    Kostas Papanotas; Petros A. Kokkinos; Panos G. Ziros; Apostolos Vantarakis

    2012-01-01

    The objective of this study was the application and evaluation of a loop-mediated isothermal amplification (LAMP) method for the detection of Salmonella spp. strains isolated from food samples. Salmonella specific invA gene sequences (50 strains, 15 serotypes) were amplified at 65oC in 60 min. All of the strains of Salmonella subsp. Enterica were shown to be positive using the LAMP reaction assay, whereas, all other bacteria, virus and yeasts tested in this study were negative. LAMP products ...

  15. Isolation and identification of Salmonella spp. in drinking water, streams, and swine wastewater by molecular techniques in Taiwan

    Science.gov (United States)

    Kuo, C.; Hsu, B.; Shen, T.; Tseng, S.; Tsai, J.; Huang, K.; Kao, P.; Chen, J.

    2013-12-01

    Salmonella spp. is a common water-borne pathogens and its genus comprises more than 2,500 serotypes. Major pathogenic genotypes which cause typhoid fever, enteritis and other intestinal-type diseases are S. Typhimurium, S. Enteritidis, S. Stanley, S. Agona, S.Albany, S. Schwarzengrund, S. Newport, S. Choleraesuis, and S. Derby. Hence, the identification of the serotypes of Salmonella spp. is important. In the present study, the analytical procedures include direct concentration method, non-selective pre-enrichment method and selective enrichment method of Salmonella spp.. Both selective enrichment method and cultured bacteria were detected with specific primers of Salmonella spp. by polymerase chain reaction (PCR). At last, the serotypes of Salmonella were confirmed by using MLST (multilocus sequence typing) with aroC, dnaN, hemD, hisD, purE, sucA, thrA housekeeping genes to identify the strains of positive samples. This study contains 121 samples from three different types of water sources including the drinking water (51), streams (45), and swine wastewater (25). Thirteen samples with positive invA gene are separated from culture method. The strains of these positive samples which identified from MLST method are S. Albany, S. Typhimurium, S. Newport, S. Bareilly, and S. Derby. Some of the serotypes, S. Albany, S. Typhimurium and S. Newport, are highly pathogenic which correlated to human diarrhea. In our results, MLST is a useful method to identify the strains of Salmonella spp.. Keywords: Salmonella, PCR, MLST.

  16. Detection and Identification of Salmonella spp. in Surface Water by Molecular Technology in Taiwan

    Science.gov (United States)

    Tseng, S. F.; Hsu, B. M.; Huang, K. H.; Hsiao, H. Y.; Kao, P. M.; Shen, S. M.; Tsai, H. F.; Chen, J. S.

    2012-04-01

    Salmonella spp. is classified to gram-negative bacterium and is one of the most important causal agents of waterborne diseases. The genus of Salmonella comprises more than 2,500 serotypes and its taxonomy is also very complicated. In tradition, the detection of Salmonella in environmental water samples by routines culture methods using selective media and characterization of suspicious colonies based on biochemical tests and serological assay are generally time and labor consuming. To overcome this disadvantage, it is desirable to use effective method which provides a higher discrimination and more rapid identification about Salmonella in environmental water. The aim of this study is to investigate the occurrence of Salmonella using novel procedures of detection method and to identify the serovars of Salmonella isolates from 157 surface water samples in Taiwan. The procedures include membrane filtration, non-selective pre-enrichment, selective enrichment of Salmonella, and then isolation of Salmonella strains by selective culture plates. The selective enrichment and culture plates were both detected by PCR. Finally, we used biochemical tests and serological assay to confirm the serovars of Salmonella and also used Pulsed-field gel electrophoresis (PFGE) to identify their sarovar catagories by the genetic pattern. In this study, 44 water samples (28%) were indentified as Salmonella. The 44 positive water samples by culture method were further identified as S. Agona(1/44), S. Albany (10/44), S. Bareilly (13/44),S. Choleraesuis (2/44),S. Derby (4/44),S. Isangi (3/44),S.Kedougou(3/44),S. Mbandaka(1/44),S.Newport (3/44), S. Oranienburg(1/44), S. Potsdam (1/44),S. Typhimurium (1/44), andS. Weltevreden(1/44) by PFGE. The presence of Salmonella in surface water indicates the possibility of waterborne transmission in drinking watershed if water is not adequately treated. Therefore, the authorities need to have operating systems that currently provide adequate source

  17. Live attenuated S. Typhimurium vaccine with improved safety in immuno-compromised mice.

    Directory of Open Access Journals (Sweden)

    Balamurugan Periaswamy

    Full Text Available Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine's performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV. Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb(-/-nos2(-/- animals lacking NADPH oxidase and inducible NO synthase. In cybb(-/-nos2(-/- mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093, was >1000-fold attenuated in cybb(-/-nos2(-/- mice and ≈100 fold attenuated in tnfr1(-/- animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety.

  18. Lactobacillus bulgaricus, Lactobacillus rhamnosus and Lactobacillus paracasei Attenuate Salmonella Enteritidis, Salmonella Heidelberg and Salmonella Typhimurium Colonization and Virulence Gene Expression In Vitro.

    Science.gov (United States)

    Muyyarikkandy, Muhammed Shafeekh; Amalaradjou, Mary Anne

    2017-11-09

    Salmonella Enteritidis (SE), Salmonella Typhimurium (ST), and Salmonella Heidelberg (SH) have been responsible for numerous outbreaks associated with the consumption of poultry meat and eggs. Salmonella colonization in chicken is characterized by initial attachment to the cecal epithelial cells (CEC) followed by dissemination to the liver, spleen, and oviduct. Since cecal colonization is critical to Salmonella transmission along the food chain continuum, reducing this intestinal association could potentially decrease poultry meat and egg contamination. Hence, this study investigated the efficacy of Lactobacillus delbreuckii sub species bulgaricus (NRRL B548; LD), Lactobacillus paracasei (DUP-13076; LP), and Lactobacillus rhamnosus (NRRL B442; LR) in reducing SE, ST, and SH colonization in CEC and survival in chicken macrophages. Additionally, their effect on expression of Salmonella virulence genes essential for cecal colonization and survival in macrophages was evaluated. All three probiotics significantly reduced Salmonella adhesion and invasion in CEC and survival in chicken macrophages ( p < 0.05). Further, the probiotic treatment led to a significant reduction in Salmonella virulence gene expression ( p < 0.05). Results of the study indicate that LD, LP, and LR could potentially be used to control SE, ST, and SH colonization in chicken. However, these observations warrant further in vivo validation.

  19. Lactobacillus bulgaricus, Lactobacillus rhamnosus and Lactobacillus paracasei Attenuate Salmonella Enteritidis, Salmonella Heidelberg and Salmonella Typhimurium Colonization and Virulence Gene Expression In Vitro

    Directory of Open Access Journals (Sweden)

    Muhammed Shafeekh Muyyarikkandy

    2017-11-01

    Full Text Available Salmonella Enteritidis (SE, Salmonella Typhimurium (ST, and Salmonella Heidelberg (SH have been responsible for numerous outbreaks associated with the consumption of poultry meat and eggs. Salmonella colonization in chicken is characterized by initial attachment to the cecal epithelial cells (CEC followed by dissemination to the liver, spleen, and oviduct. Since cecal colonization is critical to Salmonella transmission along the food chain continuum, reducing this intestinal association could potentially decrease poultry meat and egg contamination. Hence, this study investigated the efficacy of Lactobacillus delbreuckii sub species bulgaricus (NRRL B548; LD, Lactobacillus paracasei (DUP-13076; LP, and Lactobacillus rhamnosus (NRRL B442; LR in reducing SE, ST, and SH colonization in CEC and survival in chicken macrophages. Additionally, their effect on expression of Salmonella virulence genes essential for cecal colonization and survival in macrophages was evaluated. All three probiotics significantly reduced Salmonella adhesion and invasion in CEC and survival in chicken macrophages (p < 0.05. Further, the probiotic treatment led to a significant reduction in Salmonella virulence gene expression (p < 0.05. Results of the study indicate that LD, LP, and LR could potentially be used to control SE, ST, and SH colonization in chicken. However, these observations warrant further in vivo validation.

  20. Validation of a Salmonella loop-mediated isothermal amplification assay in animal food.

    Science.gov (United States)

    Domesle, Kelly J; Yang, Qianru; Hammack, Thomas S; Ge, Beilei

    2018-01-02

    Loop-mediated isothermal amplification (LAMP) has emerged as a promising alternative to PCR for pathogen detection in food testing and clinical diagnostics. This study aimed to validate a Salmonella LAMP method run on both turbidimetry (LAMP I) and fluorescence (LAMP II) platforms in representative animal food commodities. The U.S. Food and Drug Administration (FDA)'s culture-based Bacteriological Analytical Manual (BAM) method was used as the reference method and a real-time quantitative PCR (qPCR) assay was also performed. The method comparison study followed the FDA's microbiological methods validation guidelines, which align well with those from the AOAC International and ISO. Both LAMP assays were 100% specific among 300 strains (247 Salmonella of 185 serovars and 53 non-Salmonella) tested. The detection limits ranged from 1.3 to 28 cells for six Salmonella strains of various serovars. Six commodities consisting of four animal feed items (cattle feed, chicken feed, horse feed, and swine feed) and two pet food items (dry cat food and dry dog food) all yielded satisfactory results. Compared to the BAM method, the relative levels of detection (RLODs) for LAMP I ranged from 0.317 to 1 with a combined value of 0.610, while those for LAMP II ranged from 0.394 to 1.152 with a combined value of 0.783, which all fell within the acceptability limit (2.5) for an unpaired study. This also suggests that LAMP was more sensitive than the BAM method at detecting low-level Salmonella contamination in animal food and results were available 3days sooner. The performance of LAMP on both platforms was comparable to that of qPCR but notably faster, particularly LAMP II. Given the importance of Salmonella in animal food safety, the LAMP assays validated in this study holds great promise as a rapid, reliable, and robust method for routine screening of Salmonella in these commodities. Published by Elsevier B.V.

  1. What makes ribosome-mediated transcriptional attenuation sensitive to amino acid limitation?

    Directory of Open Access Journals (Sweden)

    Johan Elf

    2005-06-01

    Full Text Available Ribosome-mediated transcriptional attenuation mechanisms are commonly used to control amino acid biosynthetic operons in bacteria. The mRNA leader of such an operon contains an open reading frame with "regulatory" codons, cognate to the amino acid that is synthesized by the enzymes encoded by the operon. When the amino acid is in short supply, translation of the regulatory codons is slow, which allows transcription to continue into the structural genes of the operon. When amino acid supply is in excess, translation of regulatory codons is rapid, which leads to termination of transcription. We use a discrete master equation approach to formulate a probabilistic model for the positioning of the RNA polymerase and the ribosome in the attenuator leader sequence. The model describes how the current rate of amino acid supply compared to the demand in protein synthesis (signal determines the expression of the amino acid biosynthetic operon (response. The focus of our analysis is on the sensitivity of operon expression to a change in the amino acid supply. We show that attenuation of transcription can be hyper-sensitive for two main reasons. The first is that its response depends on the outcome of a race between two multi-step mechanisms with synchronized starts: transcription of the leader of the operon, and translation of its regulatory codons. The relative change in the probability that transcription is aborted (attenuated can therefore be much larger than the relative change in the time it takes for the ribosome to read a regulatory codon. The second is that the general usage frequencies of codons of the type used in attenuation control are small. A small percentage decrease in the rate of supply of the controlled amino acid can therefore lead to a much larger percentage decrease in the rate of reading a regulatory codon. We show that high sensitivity further requires a particular choice of regulatory codon among several synonymous codons for the

  2. The Agricultural Antibiotic Carbadox Induces Phage-mediated Gene Transfer in Salmonella

    Directory of Open Access Journals (Sweden)

    Bradley L. Bearson

    2014-02-01

    Full Text Available Antibiotics are used for disease therapeutic or preventative effects in humans and animals, as well as for enhanced feed conversion efficiency in livestock. Antibiotics can also cause undesirable effects in microbial populations, including selection for antibiotic resistance, enhanced pathogen invasion, and stimulation of horizontal gene transfer. Carbadox is a veterinary antibiotic used in the U.S. during the starter phase of swine production for improved feed efficiency and control of swine dysentery and bacterial swine enteritis. Carbadox has been shown in vitro to induce phage-encoded Shiga toxin in Shiga toxin-producing Escherichia coli and a phage-like element transferring antibiotic resistance genes in Brachyspira hyodysenteriae, but the effect of carbadox on prophages in other bacteria is unknown. This study examined carbadox exposure on prophage induction and genetic transfer in Salmonella enterica serovar Typhimurium, a human foodborne pathogen that frequently colonizes swine without causing disease. S. Typhimurium LT2 exposed to carbadox induced prophage production, resulting in bacterial cell lysis and release of virions that were visible by electron microscopy. Carbadox induction of phage-mediated gene transfer was confirmed by monitoring the transduction of a sodCIII::neo cassette in the Fels-1 prophage from LT2 to a recipient Salmonella strain. Furthermore, carbadox frequently induced generalized transducing phages in multidrug-resistant phage type DT104 and DT120 isolates, resulting in the transfer of chromosomal and plasmid DNA that included antibiotic resistance genes. Our research indicates that exposure of Salmonella to carbadox induces prophages that can transfer virulence and antibiotic resistance genes to susceptible bacterial hosts. Carbadox-induced, phage-mediated gene transfer could serve as a contributing factor in bacterial evolution during animal production, with prophages being a reservoir for bacterial fitness

  3. Oral vaccination with LcrV from Yersinia pestis KIM delivered by live attenuated Salmonella enterica serovar Typhimurium elicits a protective immune response against challenge with Yersinia pseudotuberculosis and Yersinia enterocolitica.

    Science.gov (United States)

    Branger, Christine G; Torres-Escobar, Ascención; Sun, Wei; Perry, Robert; Fetherston, Jacqueline; Roland, Kenneth L; Curtiss, Roy

    2009-08-27

    The use of live recombinant attenuated Salmonella vaccines (RASV) synthesizing Yersinia proteins is a promising approach for controlling infection by Yersinia species. In this study, we constructed attenuated Salmonella strains which synthesize a truncated form of LcrV, LcrV196 and evaluated the immune response and protective efficacy elicited by these strains in mice against two other major species of Yersinia: Yersinia pseudotuberculosis and Yersinia enterocolitica. Surprisingly, we found that the RASV strain alone was sufficient to afford nearly full protection against challenge with Y. pseudotuberculosis, indicating the likelihood that Salmonella produces immunogenic cross-protective antigens. In contrast, lcrV196 expression was required for protection against challenge with Y. enterocolitica strain 8081, but was not sufficient to achieve significant protection against challenge with Y. enterocolitica strain WA, which expressed a divergent form of lcrV. Nevertheless, we are encouraged by these findings to continue pursuing our long-term goal of developing a single vaccine to protect against all three human pathogenic species of Yersinia.

  4. Multiple antigens of Yersinia pestis delivered by live recombinant attenuated Salmonella vaccine strains elicit protective immunity against plague.

    Science.gov (United States)

    Sanapala, Shilpa; Rahav, Hannah; Patel, Hetal; Sun, Wei; Curtiss, Roy

    2016-05-05

    Based on our improved novel Salmonella vaccine delivery platform, we optimized the recombinant attenuated Salmonella typhimurium vaccine (RASV) χ12094 to deliver multiple Yersinia pestis antigens. These included LcrV196 (amino acids, 131-326), Psn encoded on pYA5383 and F1 encoded in the chromosome, their synthesis did not cause adverse effects on bacterial growth. Oral immunization with χ12094(pYA5383) simultaneously stimulated high antibody titers to LcrV, Psn and F1 in mice and presented complete protection against both subcutaneous (s.c.) and intranasal (i.n.) challenges with high lethal doses of Y. pestis CO92. Moreover, no deaths or other disease symptoms were observed in SCID mice orally immunized with χ12094(pYA5383) over a 60-day period. Therefore, the trivalent S. typhimurium-based live vaccine shows promise for a next-generation plague vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Cell-associated flagella enhance the protection conferred by mucosally-administered attenuated Salmonella Paratyphi A vaccines.

    Directory of Open Access Journals (Sweden)

    Orit Gat

    2011-11-01

    Full Text Available Antibiotic-resistant Salmonella enterica serovar Paratyphi A, the agent of paratyphoid A fever, poses an emerging public health dilemma in endemic areas of Asia and among travelers, as there is no licensed vaccine. Integral to our efforts to develop a S. Paratyphi A vaccine, we addressed the role of flagella as a potential protective antigen by comparing cell-associated flagella with exported flagellin subunits expressed by attenuated strains.S. Paratyphi A strain ATCC 9150 was first deleted for the chromosomal guaBA locus, creating CVD 1901. Further chromosomal deletions in fliD (CVD 1901D or flgK (CVD 1901K were then engineered, resulting in the export of unpolymerized FliC, without impairing its overall expression. The virulence of the resulting isogenic strains was examined using a novel mouse LD(50 model to accommodate the human-host restricted S. Paratyphi A. The immunogenicity of the attenuated strains was then tested using a mouse intranasal model, followed by intraperitoneal challenge with wildtype ATCC 9150.Mucosal (intranasal immunization of mice with strain CVD 1901 expressing cell-associated flagella conferred superior protection (vaccine efficacy [VE], 90% against a lethal intraperitoneal challenge, compared with the flagellin monomer-exporting mutants CVD 1901K (30% VE or CVD 1901D (47% VE. The superior protection induced by CVD 1901 with its cell-attached flagella was associated with an increased IgG2a:IgG1 ratio of FliC-specific antibodies with enhanced opsonophagocytic capacity.Our results clearly suggest that enhanced anti-FliC antibody-mediated clearance of S. Paratyphi A by phagocytic cells, induced by vaccines expressing cell-associated rather than exported FliC, might be contributing to the vaccine-induced protection from S. Paratyphi A challenge in vivo. We speculate that an excess of IgG1 anti-FliC antibodies induced by the exported FliC may compete with the IgG2a subtype and block binding to specific phagocyte Fc

  6. ORF Sequence: NC_006905 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available of cations and cationic drugs [Salmonella enterica subsp. enterica serovar Choleraesuis str. SC-B67] MFYWILL... NC_006905 gi|62180070 >gi|62180070|ref|YP_216487.1| putative membrane transporter

  7. ORF Sequence: NC_006905 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available of cations and cationic drugs [Salmonella enterica subsp. enterica serovar Choleraesuis str. SC-B67] MQQFEWI... NC_006905 gi|62180071 >gi|62180071|ref|YP_216488.1| putative membrane transporter

  8. ORF Alignment: NC_006905 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... involved in its turnover [Salmonella enterica subsp. ... enterica serovar Choleraesuis str.... ... division and FtsZ ring formation upon DNA ... damage/inhibition, HslVU and Lon involved in its ... turnover

  9. B Cell Receptor-Mediated Internalization of Salmonella: A Novel Pathway for Autonomous B Cell Activation and Antibody Production

    NARCIS (Netherlands)

    Souwer, Yuri; Griekspoor, Alexander; Jorritsma, Tineke; de Wit, Jelle; Janssen, Hans; Neefjes, Jacques; van Ham, S. Marieke

    2009-01-01

    The present paradigm is that primary B cells are nonphagocytosing cells. In this study, we demonstrate that human primary B cells are able to internalize bacteria when the bacteria are recognized by the BCR. BCR-mediated internalization of Salmonella typhimurium results in B cell differentiation and

  10. [The gentic principles for the design of live Salmonella vaccines].

    Science.gov (United States)

    Petrovskaia, V G; Marakusha, B I; Bondarenko, V M

    1996-01-01

    The presently known methods of obtaining Salmonella vaccine strains are characterized, their advantages and drawbacks are noted. Great importance of the genetic safety of Salmonella attenuated strains to be controlled is emphasized, taking into account that they are also used as carrier strains for obtaining hybrid and gene-engineering (vector) vaccines carrying immunogenicity factors of other species of pathogenic microorganisms.

  11. Differential outcome of infection with attenuated Salmonella in MyD88-deficient mice is dependent on the route of administration.

    Science.gov (United States)

    Issac, Jincy M; Sarawathiamma, Dhanya; Al-Ketbi, Mai I; Azimullah, Sheikh; Al-Ojali, Samia M; Mohamed, Yassir A; Flavell, Richard A; Fernandez-Cabezudo, Maria J; al-Ramadi, Basel K

    2013-01-01

    Activation of the innate immune system is a prerequisite for the induction of adaptive immunity to both infectious and non-infectious agents. TLRs are key components of the innate immune recognition system and detect pathogen-associated molecular patterns. Most TLRs utilize the MyD88 adaptor for their signaling pathways. In the current study, we investigated innate and adaptive immune responses to primary as well as secondary Salmonella infections in MyD88-deficient (MyD88(-/-)) mice. Using i.p. or oral route of inoculation, we demonstrate that MyD88(-/-) mice are hypersusceptible to infection by an attenuated, double auxotrophic, mutant of Salmonella enterica serovar Typhimurium (S. typhimurium). This is manifested by 2-3 logs higher bacterial loads in target organs, delayed recruitment of phagocytic cells, and defective production of proinflammatory cytokines in MyD88(-/-) mice. Despite these deficiencies, MyD88(-/-) mice developed Salmonella-specific memory Th1 responses and produced elevated serum levels of anti-Salmonella Abs, not only of Th1-driven (IgG2c, IgG3) but also IgG1 and IgG2b isotypes. Curiously, these adaptive responses were insufficient to afford full protection against a secondary challenge with a virulent strain of S. typhimurium. In comparison with the high degree of mortality seen in MyD88(-/-) mice following i.p. inoculation, oral infections led to the establishment of a state of long-term persistence, characterized by continuous bacterial shedding in animal feces that lasted for more than 6 months, but absence from systemic organs. These findings suggest that the absent expression of MyD88 affects primarily the innate effector arm of the immune system and highlights its critical role in anti-bacterial defense. Copyright © 2012 Elsevier GmbH. All rights reserved.

  12. Development of a novel loop-mediated isothermal amplification (LAMP) assay for the detection of Salmonella ser. Enteritidis from egg products

    Science.gov (United States)

    Salmonella ser. Enteritidis is a major public health concern worldwide. Loop-mediated isothermal amplification (LAMP) is a novel simple, easy-to-operate detection technology that amplifies DNA with high speed, efficiency, and specificity under isothermal conditions. The objective of this study was t...

  13. Antiproliferative and antibacterial activity evaluation of red ...

    African Journals Online (AJOL)

    Antibacterial activity of these extracts was also tested against Salmonella choleraesuis, Listeria monocytogenes and Staphylococcus aureus. All extracts were obtained from lyophilized biomass of red microalgae. Extract A was obtained using 40% ammonium sulfate precipitation and gel filtration chromatography with G-25 ...

  14. E. coli Nissle 1917 Affects Salmonella adhesion to porcine intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Peter Schierack

    Full Text Available BACKGROUND: The probiotic Escherichia coli strain Nissle 1917 (EcN has been shown to interfere in a human in vitro model with the invasion of several bacterial pathogens into epithelial cells, but the underlying molecular mechanisms are not known. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigated the inhibitory effects of EcN on Salmonella Typhimurium invasion of porcine intestinal epithelial cells, focusing on EcN effects on the various stages of Salmonella infection including intracellular and extracellular Salmonella growth rates, virulence gene regulation, and adhesion. We show that EcN affects the initial Salmonella invasion steps by modulating Salmonella virulence gene regulation and Salmonella SiiE-mediated adhesion, but not extra- and intracellular Salmonella growth. However, the inhibitory activity of EcN against Salmonella invasion always correlated with EcN adhesion capacities. EcN mutants defective in the expression of F1C fimbriae and flagellae were less adherent and less inhibitory toward Salmonella invasion. Another E. coli strain expressing F1C fimbriae was also adherent to IPEC-J2 cells, and was similarly inhibitory against Salmonella invasion like EcN. CONCLUSIONS: We propose that EcN affects Salmonella adhesion through secretory components. This mechanism appears to be common to many E. coli strains, with strong adherence being a prerequisite for an effective reduction of SiiE-mediated Salmonella adhesion.

  15. Nitrate decreases xanthine oxidoreductase-mediated nitrite reductase activity and attenuates vascular and blood pressure responses to nitrite.

    Science.gov (United States)

    Damacena-Angelis, Célio; Oliveira-Paula, Gustavo H; Pinheiro, Lucas C; Crevelin, Eduardo J; Portella, Rafael L; Moraes, Luiz Alberto B; Tanus-Santos, Jose E

    2017-08-01

    Nitrite and nitrate restore deficient endogenous nitric oxide (NO) production as they are converted back to NO, and therefore complement the classic enzymatic NO synthesis. Circulating nitrate and nitrite must cross membrane barriers to produce their effects and increased nitrate concentrations may attenuate the nitrite influx into cells, decreasing NO generation from nitrite. Moreover, xanthine oxidoreductase (XOR) mediates NO formation from nitrite and nitrate. However, no study has examined whether nitrate attenuates XOR-mediated NO generation from nitrite. We hypothesized that nitrate attenuates the vascular and blood pressure responses to nitrite either by interfering with nitrite influx into vascular tissue, or by competing with nitrite for XOR, thus inhibiting XOR-mediated NO generation. We used two independent vascular function assays in rats (aortic ring preparations and isolated mesenteric arterial bed perfusion) to examine the effects of sodium nitrate on the concentration-dependent responses to sodium nitrite. Both assays showed that nitrate attenuated the vascular responses to nitrite. Conversely, the aortic responses to the NO donor DETANONOate were not affected by sodium nitrate. Further confirming these results, we found that nitrate attenuated the acute blood pressure lowering effects of increasing doses of nitrite infused intravenously in freely moving rats. The possibility that nitrate could compete with nitrite and decrease nitrite influx into cells was tested by measuring the accumulation of nitrogen-15-labeled nitrite ( 15 N-nitrite) by aortic rings using ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS). Nitrate exerted no effect on aortic accumulation of 15 N-nitrite. Next, we used chemiluminescence-based NO detection to examine whether nitrate attenuates XOR-mediated nitrite reductase activity. Nitrate significantly shifted the Michaelis Menten saturation curve to the right, with a 3-fold increase in the

  16. A novel imageable therapeutic probe for cancer; cytolysin a expressing attenuated salmonella typhimurium

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Vu Hong; Tae, Seong Ho; Piao, Hong Hua; Hong, Yeoung Jin; Choy, Hyon E.; Bom, Hee Seung; Min, Jung Joon [Chonnam National University Medical School, Gwangju (Korea, Republic of)

    2007-07-01

    Oncolytic strategy using bacteria has a long history. With the discovery of fluorescent and luminescent reporter genes, bacteria can be easily monitored continuously in treatment process. Salmonella typhimurium ppGpp mutant, one of the prominent attenuated bacteria, has just reported recently, Therefore, in this study, we established strain Cytolysin A (Cly A) expressing light-emitting S. typhimurium ppGpp mutant. S. typhimurium ppGpp mutant was transducted by lux gene for in vivo imaging (S. typhimurium ppGpp/lux) and then, plasmid containing ClyA gene, which is encoded for a pore-forming protein toxin, was transformed to create the strain expressing haemolytic activity (S. typhimurium ppGpp/lux/ClyA). The toxicity of ClyA was evaluated in vitro by inoculating the bacteria with various cultured cancer cell lines. On the other hand, to test the therapeutic effect, the bacteria were injected intermittently, intraperitoneal y or intravenously into CT26-bearing Balb/c mice. The sizes of tumors were measured and in vivo imaging was taken everyday by IVIS machine (Xenogen). The in vitro result showed the number of death cells were significantly higher in the samples containing S. typhimurium ppGpp/lux/ClyA compared with the samples containing S. typhimurium ppGpp/lux. After two days injection, the growth of tumors were repressed in mice injected with either S. typhimurium ppGpp/lux/ClyA or S. typhimurium ppGpp/lux, while tumors in control group still grew fast. In day 3, the tumors inoculated with S. typhimurium ppGpp/lux/ClyA became necrosis and regressed in the following days but not in other groups. In addition, in vivo imaging data showed that the Salmonella strains selectively located in the tumor. By in vivo imaging technique, the light-emitting bacteria can be easily monitored and quantified non-invasively and repeatedly. And ClyA expressing light-emitting S. typhimurium ppGpp mutant can become an effective and safely candidate for cancer treatment.

  17. Comprehensive identification of Salmonella enterica serovar typhimurium genes required for infection of BALB/c mice.

    Directory of Open Access Journals (Sweden)

    Roy R Chaudhuri

    2009-07-01

    Full Text Available Genes required for infection of mice by Salmonella Typhimurium can be identified by the interrogation of random transposon mutant libraries for mutants that cannot survive in vivo. Inactivation of such genes produces attenuated S. Typhimurium strains that have potential for use as live attenuated vaccines. A quantitative screen, Transposon Mediated Differential Hybridisation (TMDH, has been developed that identifies those members of a large library of transposon mutants that are attenuated. TMDH employs custom transposons with outward-facing T7 and SP6 promoters. Fluorescently-labelled transcripts from the promoters are hybridised to whole-genome tiling microarrays, to allow the position of the transposon insertions to be determined. Comparison of microarray data from the mutant library grown in vitro (input with equivalent data produced after passage of the library through mice (output enables an attenuation score to be determined for each transposon mutant. These scores are significantly correlated with bacterial counts obtained during infection of mice using mutants with individual defined deletions of the same genes. Defined deletion mutants of several novel targets identified in the TMDH screen are effective live vaccines.

  18. Allele-specific primer polymerase chain reaction for a single nucleotide polymorphism (C1205T) of swine Toll-like receptor 5 and comparison of the allelic frequency among several pig breeds in Japan and the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Muneta, Y.; Minagawa, Y.; Kusumoto, M.; Shinkai, H.; Uenishi, H.; Šplíchal, Igor

    2012-01-01

    Roč. 56, č. 6 (2012), s. 385-391 ISSN 0385-5600 R&D Projects: GA ČR GA524/09/0365 Institutional support: RVO:61388971 Keywords : allele-specific PCR * Salmonella enterica serovar Choleraesuis * single nucleotide polymorphism Subject RIV: EC - Immunology Impact factor: 1.545, year: 2012

  19. Characterization of integron mediated antimicrobial resistance in Salmonella isolated from diseased swine

    Science.gov (United States)

    White, David G.; Zhao, Shaohua; McDermott, Patrick F.; Ayers, Sherry; Friedman, Sharon; Sherwood, Julie; Breider-Foley, Missy; Nolan, Lisa K.

    2003-01-01

    Forty-two Salmonella isolates obtained from diseased swine were genetically characterized for the presence of specific antimicrobial resistance mechanisms. Twenty of these isolates were characterized as S. Typhimurium DT104 strains. Pulsed-field gel electrophoresis was used to determine genetic relatedness and revealed 20 distinct genetic patterns among the 42 isolates. However, all DT104 isolates fell within 2 closely related genetic clusters. Other Salmonella isolates were genetically grouped together according to serotype. All DT104 isolates displayed the penta-resistance phenotype to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline. Resistance to sulfamethoxazole, tetracycline, streptomycin, kanamycin, and ampicillin was most common among the non-DT104 Salmonella isolates. All DT104 strains contained 2 chromosomal integrons of 1000 and 1200 base pairs. The DNA sequencing revealed that the 2 integrons contained genes encoding a resistance to streptomycin and ampicillin, respectively. None of the non-DT104 strains showed the same pattern, although several strains possessed integrons of 1000 base pairs or larger. However, the majority of non-DT104 Salmonella strains did not possess any integrons. Two Salmonella isolates displayed tolerance to the organic solvent cyclohexane, indicating the possibility that they are overexpressing chromosomal regulatory genes marA or soxS or the associated multidrug efflux pump, acrAB. This research suggests that integrons contribute to antimicrobial resistance among specific swine Salmonella serotypes; however, they are not as widely disseminated among non-Typhimurium swine Salmonella serotypes as previously thought. PMID:12528827

  20. Co-ordinate regulation of Salmonella typhimurium invasion genes by environmental and regulatory factors is mediated by control of hilA expression.

    Science.gov (United States)

    Bajaj, V; Lucas, R L; Hwang, C; Lee, C A

    1996-11-01

    During infection of their hosts, salmonellae enter intestinal epithelial cells. It has been proposed that when Salmonella typhimurium is present in the intestinal lumen, several environmental and regulatory conditions modulate the expression of invasion factors required for bacterial entry into host cells. We report here that the expression of six different S. typhimurium invasion genes encoded on SPI1 (Salmonella pathogenicity island 1) is co-ordinately regulated by oxygen, osmolarity, pH, PhoPQ, and HilA. HilA is a transcriptional activator of the OmpR/ToxR family that is also encoded on SPI1. We have found that HilA plays a central role in the co-ordinated regulation of invasion genes by environmental and regulatory conditions. HilA can activate the expression of two invasion gene-lacZY fusions on reporter plasmids in Escherichia coll, suggesting that HilA acts directly at invasion-gene promoters in S. typhimurium. We have found that the regulation of invasion genes by oxygen, osmolarity, pH, and PhoPQ is indirect and is mediated by regulation of hilA expression by these environmental and regulatory factors. We hypothesize that the complex and co-ordinate regulation of Invasion genes by HilA is an important feature of salmonella pathogenesis and allows salmonellae to enter intestinal epithelial cells.

  1. International collaborative study on the occurrence of plasmid-mediated quinolone resistance in Salmonella enterica and Escherichia coli isolated from animals, humans, food and the environment in 13 European countries

    DEFF Research Database (Denmark)

    Veldman, Kees; Cavaco, Lina; Mevius, Dik

    2011-01-01

    OBJECTIVES: This study was initiated to collect retrospective information on the occurrence of plasmid-mediated quinolone resistance (PMQR) in Salmonella enterica and Escherichia coli isolates in Europe and to identify the responsible genes. METHODS: Databases of national reference laboratories...... containing MIC values for Salmonella and E. coli isolated between 1994 and 2009 in animals, humans, food and the environment from 13 European countries were screened for isolates exhibiting a defined quinolone resistance phenotype, i.e. reduced susceptibility to fluoroquinolones and nalidixic acid. PCR...... isolate. No qnrC or qepA genes were detected in either Salmonella or E. coli. CONCLUSIONS: This study shows the occurrence and dissemination of PMQR genes in Salmonella and E. coli in Europe with a defined quinolone resistance phenotype. We also report the first detection of qnrD in Salmonella collected...

  2. Test of mutagenicity of an irradiated standard diet for laboratory animals in the host-mediated assay with salmonella typhimurium TA 1530

    International Nuclear Information System (INIS)

    Muenzner, R.; Renner, H.W.

    1976-01-01

    Feed irradiated at a dose of 3 Mrad was tested for mutagenic activity in the host-mediated assay with the mouse as host and Salmonella typhimurium TA 1530 as indicator organism. In the in vivo and in the in vitro comparative test the irradiated feed showed no mutagenic effect. (orig.) [de

  3. Suppression of immune-mediated liver injury after vaccination with attenuated pathogenic cells.

    Science.gov (United States)

    Mei, Yunhua; Wang, Ying; Xu, Lingyun

    2007-05-15

    Cell vaccination via immunization with attenuated pathogenic cells is an effective preventive method that has been successfully applied in several animal models of inflammatory or autoimmune diseases. Concanavalin A (Con A)-induced hepatitis (CIH) is a commonly used experimental model to study immune-mediated liver injury. Multiple cell types including T lymphocytes, macrophages and neutrophils have been found to be involved in the pathogenesis of CIH. In this study, we used attenuated spleen lymphocytes or peripheral blood lymphocytes as vaccines to investigate whether they could induce protective immune responses to prevent mice from developing CIH. We found that mice receiving such vaccination before CIH induction developed much milder diseases, exhibited a lower level of alanine aminotransferase (ALT) released into their plasma and had less inflammatory lesions in their livers. Such CIH-suppression is dose- and frequency-dependent. The suppressive effect was associated with inhibition of several major inflammatory mediators, pro-inflammatory cytokines and chemokines.

  4. Vulnerabilities in Yersinia pestis caf operon are unveiled by a Salmonella vector.

    Science.gov (United States)

    Cao, Ling; Lim, Timothy; Jun, SangMu; Thornburg, Theresa; Avci, Recep; Yang, Xinghong

    2012-01-01

    During infection, Yersinia pestis uses its F1 capsule to enhance survival and cause virulence to mammalian host. Since F1 is produced in large quantities and secreted into the host tissues, it also serves as a major immune target. To hold this detrimental effect under proper control, Y. pestis expresses the caf operon (encoding the F1 capsule) in a temperature-dependent manner. However, additional properties of the caf operon limit its expression. By overexpressing the caf operon in wild-type Salmonella enterica serovar Typhimurium under a potent promoter, virulence of Salmonella was greatly attenuated both in vitro and in vivo. In contrast, expression of the caf operon under the regulation of its native promoter exhibited negligible impairment of Salmonellae virulence. In-depth investigation revealed all individual genes in the caf operon attenuated Salmonella when overexpressed. The deleterious effects of caf operon and the caf individual genes were further confirmed when they were overexpressed in Y. pestis KIM6+. This study suggests that by using a weak inducible promoter, the detrimental effects of the caf operon are minimally manifested in Y. pestis. Thus, through tight regulation of the caf operon, Y. pestis precisely balances its capsular anti-phagocytic properties with the detrimental effects of caf during interaction with mammalian host.

  5. New technology for regiospecific covalent coupling of polysaccharide antigens in ELISA for serological detection

    DEFF Research Database (Denmark)

    Jauho, E.S.; Boas, Ulrik; Wiuff, Camilla

    2000-01-01

    In this study we demonstrate a new UV irradiation technique for covalent coupling of bacterial polysaccharides derived from lipopolysaccharides to microtiter plates and the use of such plates in an enzyme linked immunosorbent assay (ELISA). Lipopolysaccharides were cleaved by mild acid hydrolysis...... describe the use of this technique for the immobilization of Lipopolysaccharide derived polysaccharides from Salmonella Typhimurium and Salmonella Choleraesuis lipopolysaccharides, representing the O-antigens 1, 4, 5, 6, 7, and 12, The functional polysaccharide surface gave similar ELISA results to plates...

  6. Attenuated Salmonella enterica Serovar Typhi and Shigella flexneri 2a Strains Mucosally Deliver DNA Vaccines Encoding Measles Virus Hemagglutinin, Inducing Specific Immune Responses and Protection in Cotton Rats

    OpenAIRE

    Pasetti, Marcela F.; Barry, Eileen M.; Losonsky, Genevieve; Singh, Mahender; Medina-Moreno, Sandra M.; Polo, John M.; Ulmer, Jeffrey; Robinson, Harriet; Sztein, Marcelo B.; Levine, Myron M.

    2003-01-01

    Measles remains a leading cause of child mortality in developing countries. Residual maternal measles antibodies and immunologic immaturity dampen immunogenicity of the current vaccine in young infants. Because cotton rat respiratory tract is susceptible to measles virus (MV) replication after intranasal (i.n.) challenge, this model can be used to assess the efficacy of MV vaccines. Pursuing a new measles vaccine strategy that might be effective in young infants, we used attenuated Salmonella...

  7. Molecular study on some antibiotic resistant genes in Salmonella spp. isolates

    Science.gov (United States)

    Nabi, Ari Q.

    2017-09-01

    Studying the genes related with antimicrobial resistance in Salmonella spp. is a crucial step toward a correct and faster treatment of infections caused by the pathogen. In this work Integron mediated antibiotic resistant gene IntI1 (Class I Integrase IntI1) and some plasmid mediated antibiotic resistance genes (Qnr) were scanned among the isolated non-Typhoid Salmonellae strains with known resistance to some important antimicrobial drugs using Sybr Green real time PCR. The aim of the study was to correlate the multiple antibiotics and antimicrobial resistance of Salmonella spp. with the presence of integrase (IntI1) gene and plasmid mediated quinolone resistant genes. Results revealed the presence of Class I Integrase gene in 76% of the isolates with confirmed multiple antibiotic resistances. Moreover, about 32% of the multiple antibiotic resistant serotypes showed a positive R-PCR for plasmid mediated qnrA gene encoding for nalidixic acid and ciprofloxacin resistance. No positive results could be revealed form R-PCRs targeting qnrB or qnrS. In light of these results we can conclude that the presence of at least one of the qnr genes and/or the presence of Integrase Class I gene were responsible for the multiple antibiotic resistance to for nalidixic acid and ciprofloxacin from the studied Salmonella spp. and further studies required to identify the genes related with multiple antibiotic resistance of the pathogen.

  8. Preexisting Salmonella-specific immunity interferes with the subsequent development of immune responses against the Salmonella strains delivering H9N2 hemagglutinin.

    Science.gov (United States)

    Hajam, Irshad Ahmed; Lee, John Hwa

    2017-06-01

    Recombinant Salmonella strains expressing foreign heterologous antigens have been extensively studied as promising live vaccine delivery vehicles. In this study, we constructed attenuated smooth (S-HA) and rough (R-HA) Salmonella strains expressing hemagglutinin (HA) of H9N2, a low pathogenic avian influenza A virus. We then investigated the HA-specific immune responses following oral immunization with either S-HA or R-HA strain in chicken model. We further examined the effects of the preexisting anti-Salmonella immunity on the subsequent elicitation of the HA and the Salmonella ompA specific immune responses. Our results showed that primary immunization with either the S-HA or the R-HA strain elicited comparable HA-specific immune responses and the responses were significantly (pSalmonella vector control. When chickens were pre-immunized with the smooth Salmonella carrier alone and then vaccinated with either S-HA or R-HA strain 3, 6 and 9 weeks later, respectively, significant reductions were seen for HA-specific immune responses at week 6, a point which corresponded to the peak of the primary Salmonella-specific antibody responses. No reductions were seen at week 3 and 9, albeit, the HA-specific immune responses were boosted at week 9, a point which corresponded to the lowest primary Salmonella-specific antibody responses. The ompA recall responses remain refractory at week 3 and 6 following deliberate immunization with the carrier strain, but were significantly (pSalmonella immunity inhibits antigen-specific immune responses and this effect could be avoided by carefully selecting the time point when carrier-specific immune responses are relatively low. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. A safe vaccine (DV-STM-07 against Salmonella infection prevents abortion and confers protective immunity to the pregnant and new born mice.

    Directory of Open Access Journals (Sweden)

    Vidya Devi Negi

    Full Text Available Pregnancy is a transient immuno-compromised condition which has evolved to avoid the immune rejection of the fetus by the maternal immune system. The altered immune response of the pregnant female leads to increased susceptibility to invading pathogens, resulting in abortion and congenital defects of the fetus and a subnormal response to vaccination. Active vaccination during pregnancy may lead to abortion induced by heightened cell mediated immune response. In this study, we have administered the highly attenuated vaccine strain DeltapmrG-HM-D (DV-STM-07 in female mice before the onset of pregnancy and followed the immune reaction against challenge with virulent S. Typhimurium in pregnant mice. Here we demonstrate that DV-STM-07 vaccine gives protection against Salmonella in pregnant mice and also prevents Salmonella induced abortion. This protection is conferred by directing the immune response towards Th2 activation and Th1 suppression. The low Th1 response prevents abortion. The use of live attenuated vaccine just before pregnancy carries the risk of transmission to the fetus. We have shown that this vaccine is safe as the vaccine strain is quickly eliminated from the mother and is not transmitted to the fetus. This vaccine also confers immunity to the new born mice of vaccinated mothers. Since there is no evidence of the vaccine candidate reaching the new born mice, we hypothesize that it may be due to trans-colostral transfer of protective anti-Salmonella antibodies. These results suggest that our vaccine DV-STM-07 can be very useful in preventing abortion in the pregnant individuals and confer immunity to the new born. Since there are no such vaccine candidates which can be given to the new born and to the pregnant women, this vaccine holds a very bright future to combat Salmonella induced pregnancy loss.

  10. Mathematical model of flagella gene expression dynamics in Salmonella enterica serovar typhimurium

    OpenAIRE

    Jain, Kirti; Pradhan, Amit; Mokashi, Chaitanya; Saini, Supreet

    2015-01-01

    Flagellar assembly in Salmonella is controlled by an intricate genetic and biochemical network. This network comprises of a number of inter-connected feedback loops, which control the assembly process dynamically. Critical among these are the FliA–FlgM feedback, FliZ-mediated positive feedback, and FliT-mediated negative feedback. In this work, we develop a mathematical model to track the dynamics of flagellar gene expression in Salmonella. Analysis of our model demonstrates that the network ...

  11. Salmonella

    Science.gov (United States)

    ... Compartir Find out about Salmonella infections linked to Kellogg’s Honey Smacks Cereal Find out about Salmonella infections ... Outbreaks Multistate Outbreak of Salmonella Infections Linked to Kellogg’s Honey Smacks Cereal Multistate Outbreak of Salmonella Adelaide ...

  12. Selected lactic acid-producing bacterial isolates with the capacity to reduce Salmonella translocation and virulence gene expression in chickens.

    Directory of Open Access Journals (Sweden)

    Xiaojian Yang

    Full Text Available BACKGROUND: Probiotics have been used to control Salmonella colonization/infection in chickens. Yet the mechanisms of probiotic effects are not fully understood. This study has characterized our previously-selected lactic acid-producing bacterial (LAB isolates for controlling Salmonella infection in chickens, particularly the mechanism underlying the control. METHODOLOGY/PRINCIPAL FINDINGS: In vitro studies were conducted to characterize 14 LAB isolates for their tolerance to low pH (2.0 and high bile salt (0.3-1.5% and susceptibility to antibiotics. Three chicken infection trials were subsequently carried out to evaluate four of the isolates for reducing the burden of Salmonella enterica serovar Typhimurium in the broiler cecum. Chicks were gavaged with LAB cultures (10(6-7 CFU/chick or phosphate-buffered saline (PBS at 1 day of age followed by Salmonella challenge (10(4 CFU/chick next day. Samples of cecal digesta, spleen, and liver were examined for Salmonella counts on days 1, 3, or 4 post-challenge. Salmonella in the cecum from Trial 3 was also assessed for the expression of ten virulence genes located in its pathogenicity island-1 (SPI-1. These genes play a role in Salmonella intestinal invasion. Tested LAB isolates (individuals or mixed cultures were unable to lower Salmonella burden in the chicken cecum, but able to attenuate Salmonella infection in the spleen and liver. The LAB treatments also reduced almost all SPI-1 virulence gene expression (9 out of 10 in the chicken cecum, particularly at the low dose. In vitro treatment with the extracellular culture fluid from a LAB culture also down-regulated most SPI-1 virulence gene expression. CONCLUSIONS/SIGNIFICANCE: The possible correlation between attenuation of Salmonella infection in the chicken spleen and liver and reduction of Salmonella SPI-1 virulence gene expression in the chicken cecum by LAB isolates is a new observation. Suppression of Salmonella virulence gene expression in

  13. Classification and structural analysis of live and dead salmonella cells using fourier transform infrared (FT-IR) spectroscopy and principle component analysis (PCA)

    Science.gov (United States)

    Fourier Transform Infrared Spectroscopy (FT-IR) was used to detect Salmonella typhimurium and Salmonella enteritidis foodborne bacteria and distinguish between live and dead cells of both serotypes. Bacteria were loaded individually on the ZnSe Attenuated Total Reflection (ATR) crystal surface and s...

  14. Stably Integrated luxCDABE for Assessment of Salmonella Invasion Kinetics

    Directory of Open Access Journals (Sweden)

    Kelly N. Flentie

    2008-09-01

    Full Text Available Salmonella Typhimurium is a common cause of gastroenteritis in humans and also localizes to neoplastic tumors in animals. Invasion of specific eukaryotic cells is a key mechanism of Salmonella interactions with host tissues. Early stages of gastrointestinal cell invasion are mediated by a Salmonella type III secretion system, powered by the adenosine triphosphatase invC. The aim of this work was to characterize the invC dependence of invasion kinetics into disparate eukaryotic cells traditionally used as models of gut epithelium or neoplasms. Thus, a nondestructive real-time assay was developed to report eukaryotic cell invasion kinetics using lux+ Salmonella that contain chromosomally integrated luxCDABE genes. Bioluminescence-based invasion assays using lux+ Salmonella exhibited inoculum dose-response correlation, distinguished invasion-competent from invasion-incompetent Salmonella, and discriminated relative Salmonella invasiveness in accordance with environmental conditions that induce invasion gene expression. In standard gentamicin protection assays, bioluminescence from lux+ Salmonella correlated with recovery of colony-forming units of internalized bacteria and could be visualized by bioluminescence microscopy. Furthermore, this assay distinguished invasion-competent from invasion-incompetent bacteria independent of gentamicin treatment in real time. Bioluminescence reported Salmonella invasion of disparate eukaryotic cell lines, including neoplastic melanoma, colon adenocarcinoma, and glioma cell lines used in animal models of malignancy. In each case, Salmonella invasion of eukaryotic cells was invC dependent.

  15. Lactococcus lactis subsp. cremoris strain JFR1 attenuates Salmonella adhesion to human intestinal cells in vitro.

    Science.gov (United States)

    Zhang, Justina Su; Guri, Anilda; Corredig, Milena; Morales-Rayas, Rocio; Hassan, Ashraf; Griffiths, Mansel; LaPointe, Gisèle

    2016-12-01

    Lactococcus lactis subsp. cremoris JFR1 has been studied in reduced fat cheese due to its ability to produce exopolysaccharides (EPS) in situ, contributing to improved textural and organoleptic properties. In this study, the effect of strain JFR1 on virulence gene expression and attachment of Salmonella to HT-29 human colon carcinoma cells was investigated. Overnight cultures of L. lactis subsp. cremoris JFR1 containing EPS, grown in M17 media with 0.5% glucose supplementation, decreased attachment as well as down regulated virulence gene expression in Salmonella enterica subsp. enterica when tested on HT-29 cells. However, EPS isolated from milk fermented with L. lactis subsp. cremoris JFR1 did not affect Salmonella virulence gene expression or attachment to HT-29 cells. These results suggest that EPS does not contribute to the attachment of Salmonella to human intestinal cells. However, the possibility that the isolation process may have affected the structural features of EPS cannot be ruled out. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Exercise training prevents the attenuation of anesthetic pre-conditioning-mediated cardioprotection in diet-induced obese rats.

    Science.gov (United States)

    Li, L; Meng, F; Li, N; Zhang, L; Wang, J; Wang, H; Li, D; Zhang, X; Dong, P; Chen, Y

    2015-01-01

    Obesity abolishes anesthetic pre-conditioning-induced cardioprotection due to impaired reactive oxygen species (ROS)-mediated adenosine monophosphate-activated protein kinase (AMPK) pathway, a consequence of increased basal myocardial oxidative stress. Exercise training has been shown to attenuate obesity-related oxidative stress. This study tests whether exercise training could normalize ROS-mediated AMPK pathway and prevent the attenuation of anesthetic pre-conditioning-induced cardioprotection in obesity. Male Sprague-Dawley rats were divided into lean rats fed with control diet and obese rats fed with high-fat diet. After 4 weeks of feeding, lean and obese rats were assigned to sedentary conditions or treadmill exercise for 8 weeks. There was no difference in infarct size between lean sedentary and obese sedentary rats after 25 min of myocardial ischemia followed by 120 min reperfusion. In lean rats, sevoflurane equally reduced infarct size in lean sedentary and lean exercise-trained rats. Molecular studies revealed that AMPK activity, endothelial nitric oxide synthase, and superoxide production measured at the end of ischemia in lean rats were increased in response to sevoflurane. In obese rats, sevoflurane increased the above molecular parameters and reduced infarct size in obese exercise-trained rats but not in obese sedentary rats. Additional study showed that obese exercise-trained rats had decreased basal oxidative stress than obese sedentary rats. The results indicate that exercise training can prevent the attenuation of anesthetic cardioprotection in obesity. Preventing the attenuation of this strategy may be associated with reduced basal oxidative stress and normalized ROS-mediated AMPK pathway, but the causal relationship remains to be determined. © 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  17. Involvement of glucocorticoid-mediated Zn2+ signaling in attenuation of hippocampal CA1 LTP by acute stress.

    Science.gov (United States)

    Takeda, Atsushi; Suzuki, Miki; Tamano, Haruna; Takada, Shunsuke; Ide, Kazuki; Oku, Naoto

    2012-03-01

    Glucocorticoid-glutamatergic interactions have been proposed as a potential model to explain stress-mediated impairment of cognition. However, it is unknown whether glucocorticoid-zincergic interactions are involved in this impairment. Histochemically reactive zinc (Zn(2+)) is co-released with glutamate from zincergic neurons. In the present study, involvement of synaptic Zn(2+) in stress-induced attenuation of CA1 LTP was examined in hippocampal slices from young rats after exposure to tail suspension stress for 30s, which significantly increased serum corticosterone. Stress-induced attenuation of CA1 LTP was ameliorated by administration of clioquinol, a membrane permeable zinc chelator, to rats prior to exposure to stress, implying that the reduction of synaptic Zn(2+) by clioquinol participates in this amelioration. To pursue the involvement of corticosterone-mediated Zn(2+) signal in the attenuated CA1 LTP by stress, dynamics of synaptic Zn(2+) was checked in hippocampal slices exposed to corticosterone. Corticosterone increased extracellular Zn(2+) levels measured with ZnAF-2 dose-dependently, as well as the intracellular Ca(2+) levels measured with calcium orange AM, suggesting that corticosterone excites zincergic neurons in the hippocampus and increases Zn(2+) release from the neuron terminals. Intracellular Zn(2+) levels measured with ZnAF-2DA were also increased dose-dependently, but not in the coexistence of CaEDTA, a membrane-impermeable zinc chelator, suggesting that intracellular Zn(2+) levels is increased by the influx of extracellular Zn(2+). Furthermore, corticosterone-induced attenuation of CA1 LTP was abolished in the coexistence of CaEDTA. The present study suggests that corticosterone-mediated increase in postsynaptic Zn(2+) signal in the cytosolic compartment is involved in the attenuation of CA1 LTP after exposure to acute stress. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. ORF Alignment: NC_006905 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_006905 gi|62181272 >1gdtA 1 182 1 183 1e-47 ... ref|YP_217689.1| H inversion: regu...lation of flagellar gene expression by ... site-specific inversion of DNA [Salmonella enterica ... ... ... subsp. enterica serovar Choleraesuis str. SC-B67] ... gb|AAX66608.1| H inversion: regulation of ...flagellar gene ... expression by site-specific inversion of DNA [Salmonell

  19. Salmonella Disrupts Host Endocytic Trafficking by SopD2-Mediated Inhibition of Rab7

    Directory of Open Access Journals (Sweden)

    Vanessa M. D’Costa

    2015-09-01

    Full Text Available Intracellular bacterial pathogens of a diverse nature share the ability to evade host immunity by impairing trafficking of endocytic cargo to lysosomes for degradation, a process that is poorly understood. Here, we show that the Salmonella enterica type 3 secreted effector SopD2 mediates this process by binding the host regulatory GTPase Rab7 and inhibiting its nucleotide exchange. Consequently, this limits Rab7 interaction with its dynein- and kinesin-binding effectors RILP and FYCO1 and thereby disrupts host-driven regulation of microtubule motors. Our study identifies a bacterial effector capable of directly binding and thereby modulating Rab7 activity and a mechanism of endocytic trafficking disruption that may provide insight into the pathogenesis of other bacteria. Additionally, we provide a powerful tool for the study of Rab7 function, and a potential therapeutic target.

  20. Lactobacillus rhamnosus L34 Attenuates Gut Translocation-Induced Bacterial Sepsis in Murine Models of Leaky Gut.

    Science.gov (United States)

    Panpetch, Wimonrat; Chancharoenthana, Wiwat; Bootdee, Kanthika; Nilgate, Sumanee; Finkelman, Malcolm; Tumwasorn, Somying; Leelahavanichkul, Asada

    2018-01-01

    Gastrointestinal (GI) bacterial translocation in sepsis is well known, but the role of Lactobacillus species probiotics is still controversial. We evaluated the therapeutic effects of Lactobacillus rhamnosus L34 in a new sepsis model of oral administration of pathogenic bacteria with GI leakage induced by either an antibiotic cocktail (ATB) and/or dextran sulfate sodium (DSS). GI leakage with ATB, DSS, and DSS plus ATB (DSS+ATB) was demonstrated by fluorescein isothiocyanate (FITC)-dextran translocation to the circulation. The administration of pathogenic bacteria, either Klebsiella pneumoniae or Salmonella enterica serovar Typhimurium, enhanced translocation. Bacteremia was demonstrated within 24 h in 50 to 88% of mice with GI leakage plus the administration of pathogenic bacteria but not with GI leakage induction alone or bacterial gavage alone. Salmonella bacteremia was found in only 16 to 29% and 0% of mice with Salmonella and Klebsiella administrations, respectively. Klebsiella bacteremia was demonstrated in 25 to 33% and 10 to 16% of mice with Klebsiella and Salmonella administrations, respectively. Lactobacillus rhamnosus L34 attenuated GI leakage in these models, as shown by the reductions of FITC-dextran gut translocation, serum interleukin-6 (IL-6) levels, bacteremia, and sepsis mortality. The reduction in the amount of fecal Salmonella bacteria with Lactobacillus treatment was demonstrated. In addition, an anti-inflammatory effect of the conditioned medium from Lactobacillus rhamnosus L34 was also demonstrated by the attenuation of cytokine production in colonic epithelial cells in vitro In conclusion, Lactobacillus rhamnosus L34 attenuated the severity of symptoms in a murine sepsis model induced by GI leakage and the administration of pathogenic bacteria. Copyright © 2017 American Society for Microbiology.

  1. Evaluation of 3M molecular detection assay (MDA) Salmonella for the detection of Salmonella in selected foods: collaborative study.

    Science.gov (United States)

    Bird, Patrick; Fisher, Kiel; Boyle, Megan; Huffman, Travis; Benzinger, M Joseph; Bedinghaus, Paige; Flannery, Jonathan; Crowley, Erin; Agin, James; Goins, David; Benesh, DeAnn; David, John

    2013-01-01

    The 3M Molecular Detection Assay (MDA) Salmonella is used with the 3M Molecular Detection System for the detection of Salmonella spp. in food, food-related, and environmental samples after enrichment. The assay utilizes loop-mediated isothermal amplification to rapidly amplify Salmonella target DNA with high specificity and sensitivity, combined with bioluminescence to detect the amplification. The 3M MDA Salmonella method was compared using an unpaired study design in a multilaboratory collaborative study to the U.S. Department of Agriculture/Food Safety and Inspection Service-Microbiology Laboratory Guidebook (USDA/FSIS-MLG 4.05), Isolation and Identification of Salmonella from Meat, Poultry, Pasteurized Egg and Catfish Products for raw ground beef and the U.S. Food and Drug Administration/Bacteriological Analytical Manual (FDA/BAM) Chapter 5 Salmonella reference method for wet dog food following the current AOAC guidelines. A total of 20 laboratories participated. For the 3M MDA Salmonella method, raw ground beef was analyzed using 25 g test portions, and wet dog food was analyzed using 375 g test portions. For the reference methods, 25 g test portions of each matrix were analyzed. Each matrix was artificially contaminated with Salmonella at three inoculation levels: an uninoculated control level (0 CFU/test portion), a low inoculum level (0.2-2 CFU/test portion), and a high inoculum level (2-5 CFU/test portion). In this study, 1512 unpaired replicate samples were analyzed. Statistical analysis was conducted according to the probability of detection (POD). For the low-level raw ground beef test portions, the following dLPOD (difference between the POD of the reference and candidate method) values with 95% confidence intervals were obtained: -0.01 (-0.14, +0.12). For the low-level wet dog food test portions, the following dLPOD with 95% confidence intervals were obtained: -0.04 (-0.16, +0.09). No significant differences were observed in the number of positive

  2. Comparative genomics of 28 Salmonella enterica isolates: evidence for CRISPR-mediated adaptive sublineage evolution.

    Science.gov (United States)

    Fricke, W Florian; Mammel, Mark K; McDermott, Patrick F; Tartera, Carmen; White, David G; Leclerc, J Eugene; Ravel, Jacques; Cebula, Thomas A

    2011-07-01

    Despite extensive surveillance, food-borne Salmonella enterica infections continue to be a significant burden on public health systems worldwide. As the S. enterica species comprises sublineages that differ greatly in antigenic representation, virulence, and antimicrobial resistance phenotypes, a better understanding of the species' evolution is critical for the prediction and prevention of future outbreaks. The roles that virulence and resistance phenotype acquisition, exchange, and loss play in the evolution of S. enterica sublineages, which to a certain extent are represented by serotypes, remains mostly uncharacterized. Here, we compare 17 newly sequenced and phenotypically characterized nontyphoidal S. enterica strains to 11 previously sequenced S. enterica genomes to carry out the most comprehensive comparative analysis of this species so far. These phenotypic and genotypic data comparisons in the phylogenetic species context suggest that the evolution of known S. enterica sublineages is mediated mostly by two mechanisms, (i) the loss of coding sequences with known metabolic functions, which leads to functional reduction, and (ii) the acquisition of horizontally transferred phage and plasmid DNA, which provides virulence and resistance functions and leads to increasing specialization. Matches between S. enterica clustered regularly interspaced short palindromic repeats (CRISPR), part of a defense mechanism against invading plasmid and phage DNA, and plasmid and prophage regions suggest that CRISPR-mediated immunity could control short-term phenotype changes and mediate long-term sublineage evolution. CRISPR analysis could therefore be critical in assessing the evolutionary potential of S. enterica sublineages and aid in the prediction and prevention of future S. enterica outbreaks.

  3. The Salmonella effector protein SpvC, a phosphothreonine lyase is functional in plant cells

    Directory of Open Access Journals (Sweden)

    Christina eNeumann

    2014-10-01

    Full Text Available Salmonella is one of the most prominent causes of food poisoning and growing evidence indicates that contaminated fruits and vegetables are an increasing concern for human health. Successful infection demands the suppression of the host immune system, which is often achieved via injection of bacterial effector proteins into host cells. In this report we present the function of Salmonella effector protein in plant cell, supporting the new concept of trans-kingdom competence of this bacterium. We screened a range of Salmonella Typhimurium effector proteins for interference with plant immunity. Among these, the phosphothreonine lyase SpvC attenuated the induction of immunity-related genes when present in plant cells. Using in vitro and in vivo systems we show that this effector protein interacts with and dephosphorylates activated Arabidopsis Mitogen-activated Protein Kinase 6 (MPK6, thereby inhibiting defense signaling. Moreover, the requirement of Salmonella SpvC was shown by the decreased proliferation of the ΔspvC mutant in Arabidopsis plants. These results suggest that some Salmonella effector proteins could have a conserved function during proliferation in different hosts. The fact that Salmonella and other Enterobacteriaceae use plants as hosts strongly suggests that plants represent a much larger reservoir for animal pathogens than so far estimated.

  4. The Salmonella effector protein SpvC, a phosphothreonine lyase is functional in plant cells

    KAUST Repository

    Neumann, Christina

    2014-10-17

    Salmonella is one of the most prominent causes of food poisoning and growing evidence indicates that contaminated fruits and vegetables are an increasing concern for human health. Successful infection demands the suppression of the host immune system, which is often achieved via injection of bacterial effector proteins into host cells. In this report we present the function of Salmonella effector protein in plant cell, supporting the new concept of trans-kingdom competence of this bacterium. We screened a range of Salmonella Typhimurium effector proteins for interference with plant immunity. Among these, the phosphothreonine lyase SpvC attenuated the induction of immunity-related genes when present in plant cells. Using in vitro and in vivo systems we show that this effector protein interacts with and dephosphorylates activated Arabidopsis Mitogen-activated Protein Kinase 6 (MPK6), thereby inhibiting defense signaling. Moreover, the requirement of Salmonella SpvC was shown by the decreased proliferation of the ΔspvC mutant in Arabidopsis plants. These results suggest that some Salmonella effector proteins could have a conserved function during proliferation in different hosts. The fact that Salmonella and other Enterobacteriaceae use plants as hosts strongly suggests that plants represent a much larger reservoir for animal pathogens than so far estimated.

  5. Salmonella adhesion, invasion and cellular immune responses are differentially affected by iron concentrations in a combined in vitro gut fermentation-cell model.

    Science.gov (United States)

    Dostal, Alexandra; Gagnon, Mélanie; Chassard, Christophe; Zimmermann, Michael Bruce; O'Mahony, Liam; Lacroix, Christophe

    2014-01-01

    In regions with a high infectious disease burden, concerns have been raised about the safety of iron supplementation because higher iron concentrations in the gut lumen may increase risk of enteropathogen infection. The aim of this study was to investigate interactions of the enteropathogen Salmonella enterica ssp. enterica Typhimurium with intestinal cells under different iron concentrations encountered in the gut lumen during iron deficiency and supplementation using an in vitro colonic fermentation system inoculated with immobilized child gut microbiota combined with Caco-2/HT29-MTX co-culture monolayers. Colonic fermentation effluents obtained during normal, low (chelation by 2,2'-dipyridyl) and high iron (26.5 mg iron/L) fermentation conditions containing Salmonella or pure Salmonella cultures with similar iron conditions were applied to cellular monolayers. Salmonella adhesion and invasion capacity, cellular integrity and immune response were assessed. Under high iron conditions in pure culture, Salmonella adhesion was 8-fold increased compared to normal iron conditions while invasion was not affected leading to decreased invasion efficiency (-86%). Moreover, cellular cytokines IL-1β, IL-6, IL-8 and TNF-α secretion as well as NF-κB activation in THP-1 cells were attenuated under high iron conditions. Low iron conditions in pure culture increased Salmonella invasion correlating with an increase in IL-8 release. In fermentation effluents, Salmonella adhesion was 12-fold and invasion was 428-fold reduced compared to pure culture. Salmonella in high iron fermentation effluents had decreased invasion efficiency (-77.1%) and cellular TNF-α release compared to normal iron effluent. The presence of commensal microbiota and bacterial metabolites in fermentation effluents reduced adhesion and invasion of Salmonella compared to pure culture highlighting the importance of the gut microbiota as a barrier during pathogen invasion. High iron concentrations as

  6. Attenuated RANKL-induced cytotoxicity by Portulaca oleracea ethanol extract enhances RANKL-mediated osteoclastogenesis.

    Science.gov (United States)

    Erkhembaatar, Munkhsoyol; Choi, Eun-Joo; Lee, Hak-Yong; Lee, Choong Hun; Lee, Young-Rae; Kim, Min Seuk

    2015-07-14

    Portulaca oleracea (PO) has been widely used as traditional medicine because of its pharmacological activities. However, the effects of PO on osteoclasts that modulate bone homeostasis are still elusive. In this study, we examined the effects of PO ethanol extract (POEE) on receptor activator of nuclear factor-κB ligand (RANKL)-mediated Ca(2+) mobilization, nuclear factor of activated T-cell c1 (NFATc1) amplification, tartrate-resistant acid phosphatase-positive (TRAP+) multinucleated cell (MNC) formation, and cytotoxicity. Our results demonstrated that POEE suppressed RANKL-induced Ca(2+) oscillations by inhibition of Ca(2+) release from internal Ca(2+) stores, resulting in reduction of NFATc1 amplification. Notably, POEE attenuated RANKL-mediated cytotoxicity and cleavage of polyadenosine 5'-diphosphate-ribose polymerase (PARP), resulted in enhanced formation of TRAP+ MNCs. These results present in vitro effects of POEE on RANKL-mediated osteoclastogenesis and suggest the possible use of PO in treating bone disorders, such as osteopetrosis.

  7. Salmonella osteomyelitis

    OpenAIRE

    Somsri Wiwanitkit; Viroj Wiwanitkit

    2016-01-01

    Salmonella infection can cause four predominant clinical syndromes: enteric fever, acute gastroenteritis, bacteraemia with or without metastatic infection, and the asymptomatic carrier state. Salmonella as an aetiological agent in osteomyelitis is essentially rare and salmonella osteomyelitis in itself is predominantly seen in patients with haemoglobinopathies such as sickle cell disease or thalassemia. There are very few cases reported in the literature in which salmonella osteomyelitis is s...

  8. Salmonella enterica serovar Typhimurium exploits inflammation to modify swine intestinal microbiota.

    Directory of Open Access Journals (Sweden)

    Rosanna eDrumo

    2016-01-01

    Full Text Available Salmonella enterica serovar Typhimurium is an important zoonotic gastrointestinal pathogen responsible for foodborne disease worldwide. It is a successful enteric pathogen because it has developed virulence strategies allowing it to survive in a highly inflamed intestinal environment exploiting inflammation to overcome colonization resistance provided by intestinal microbiota. In this study, we used piglets featuring an intact microbiota, which naturally develop gastroenteritis, as model for salmonellosis. We compared the effects on the intestinal microbiota induced by a wild type and an attenuated S. Typhimurium in order to evaluate whether the modifications are correlated with the virulence of the strain. This study showed that Salmonella alters microbiota in a virulence-dependent manner. We found that the wild type S. Typhimurium induced inflammation and a reduction of specific protecting microbiota species (SCFA-producing bacteria normally involved in providing a barrier against pathogens. Both these effects could contribute to impair colonization resistance, increasing the host susceptibility to wild type S. Typhimurium colonization. In contrast, the attenuated S. Typhimurium, which is characterized by a reduced ability to colonize the intestine, and by a very mild inflammatory response, was unable to successfully sustain competition with the microbiota.

  9. Salmonella: Salmonellosis

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Hansen, Trine; Maurischat, Sven

    2015-01-01

    Salmonella remains one of the most important zoonotic pathogenic bacteria and is the causative agents of salmonellosis. The aim of this article is to give an overview of Salmonella and salmonellosis, starting by describing the characteristics of the microorganism Salmonella, including biochemical...

  10. Role of nitric oxide in Salmonella typhimurium-mediated cancer cell killing

    International Nuclear Information System (INIS)

    Barak, Yoram; Schreiber, Frank; Thorne, Steve H; Contag, Christopher H; DeBeer, Dirk; Matin, A

    2010-01-01

    Bacterial targeting of tumours is an important anti-cancer strategy. We previously showed that strain SL7838 of Salmonella typhimurium targets and kills cancer cells. Whether NO generation by the bacteria has a role in SL7838 lethality to cancer cells is explored. This bacterium has the mechanism for generating NO, but also for decomposing it. Mechanism underlying Salmonella typhimurium tumour therapy was investigated through in vitro and in vivo studies. NO measurements were conducted either by chemical assays (in vitro) or using Biosensors (in vivo). Cancer cells cytotoxic assay were done by using MTS. Bacterial cell survival and tumour burden were determined using molecular imaging techniques. SL7838 generated nitric oxide (NO) in anaerobic cell suspensions, inside infected cancer cells in vitro and in implanted 4T1 tumours in live mice, the last, as measured using microsensors. Thus, under these conditions, the NO generating pathway is more active than the decomposition pathway. The latter was eliminated, in strain SL7842, by the deletion of hmp- and norV genes, making SL7842 more proficient at generating NO than SL7838. SL7842 killed cancer cells more effectively than SL7838 in vitro, and this was dependent on nitrate availability. This strain was also ca. 100% more effective in treating implanted 4T1 mouse tumours than SL7838. NO generation capability is important in the killing of cancer cells by Salmonella strains

  11. Immunogenicity of a Live Recombinant Salmonella enterica Serovar Typhimurium Vaccine Expressing pspA in Neonates and Infant Mice Born from Naïve and Immunized Mothers▿ †

    OpenAIRE

    Shi, Huoying; Wang, Shifeng; Roland, Kenneth L.; Gunn, Bronwyn M.; Curtiss, Roy

    2010-01-01

    We are developing a Salmonella vectored vaccine to prevent infant pneumonia and other diseases caused by Streptococcus pneumoniae. One prerequisite for achieving this goal is to construct and evaluate new recombinant attenuated Salmonella vaccine (RASV) strains suitable for use in neonates and infants. Salmonella enterica serovar Typhimurium strain χ9558(pYA4088) specifies delivery of the pneumococcal protective antigen PspA and can protect adult mice from challenge with S. pneumoniae. This s...

  12. Monitoring bacteriolytic therapy of salmonella typhimurium with optical imaging system

    International Nuclear Information System (INIS)

    Kim, Sun A; Min, Jung Joon; Moon, Sung Min; Kim, Hyun Ju; Kim, Sung Mi; Song, Ho Cheon; Choy, Hyon E.; Bom, Hee Seung

    2005-01-01

    Systemically administrated Salmonella has been studied for targeting tumor and developed as an anticancer agent. In Salmonella, because msbB gene plays role in the terminal myristoylation of lipid A and induces tumor necrosis factor a (TNF-a) -mediated septic shock, Salmonella msbB mutant strain is safe and useful for tumor-targeting therapy. Here we report that Salmonella msbB mutant strain induce onco lysis after intravenous injection in tumor bearing mice. The CT26 mouse colon cancer cells were stably transfected with firefly luciferase gene and subcutaneously implantated in Balb/C mice. After establishing subcutaneous tumor mass, we intravenously injected 1x108 cfu Salmonella msbB mutant strain or MG1655 E coli strain. Not only tumor size but also total photon flux from the tumor mass were monitored. everyday and compared among experimental groups (No treatment, Salmonella treatment, E. coli MG1655 treatment group). After intraperitoneal injection of D-Iuciferin (3 mg/animal), in vivo optical imaging for firefly luciferase was performed using cooled CCD camera. Imaging signal from Salmonella injected group were significantly lower than that of no treatment or E. coli treatment group on day 2 after injection. On day 4 after injection, imaging signal of salmonella-injected group was 43.8 or 20.7 times lower than that of no treatment or E. coli treatment group, respectively (no treatment: 2.78E+07 p/s/cm 2 /sr, Salmonella treatment: 6.35E+05 p/s/cm 2 /sr, E. coli treatment: 1.29E+07 p/s/cm 2 /sr, P<0.05). However. when we injected E. coli MG1655 into tumor bearing mice, the intensity of imaging signal was not different from no treatment group. These findings suggest that Salmonella msbB mutant strain retains its tumor-targeting properties and have therapeutical effect. Bioluminescent tumor bearing animal model was useful for assessing tumor viability after bacteriolytic therapy using Salmonella

  13. Overexpression of MicA induces production of OmpC-enriched outer membrane vesicles that protect against Salmonella challenge.

    Science.gov (United States)

    Choi, Hyun-Il; Kim, Moonjeong; Jeon, Jinseong; Han, Jin Kwan; Kim, Kwang-Sun

    2017-08-26

    Outer membrane vesicles (OMVs) derived from bacteria are promising candidates for subunit vaccines. Stresses that modulate the composition of outer membrane proteins (OMPs) are important for OMV synthesis. Small RNAs (sRNAs) expressed in response to stress regulate OMPs, although the mechanism underlying sRNA-mediated OMV biogenesis and its utility for developing vaccine platforms remains to be elucidated. Here, we characterized the role of a sRNA, MicA, which regulates OmpA, a major OMP involved in both production of OMVs and reactive immunity against Salmonella challenge. A Salmonella strain overexpressing MicA generated more OMVs than a control strain. In addition, OmpC was the major component of MicA-derived OMV proteins. MicA-derived OMVs induced Th1- and Th17-type immune responses in vitro and reduced Salmonella-mediated lethality in a mouse model. Thus, OmpA-regulatory sRNA-derived OMVs may facilitate production of Salmonella-protective vaccines. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Antibacterial activity of extracts of six macroalgae from the northeastern brazilian coast

    Directory of Open Access Journals (Sweden)

    Lima-Filho José Vitor M.

    2002-01-01

    Full Text Available Hexane, chloroform and ethanol extracts of six marine macroalgae (Rhodophyta and Chlorophyta from North Ceará coast (Northeast Brazil were evaluated for antibacterial activity by the single disk method. Best results were shown by the hexane extracts of Amansia multifida against enteric Gram-negative strains such as Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, S. cholerae-suis, Serratia marcescens, Vibrio cholerae and the Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus.

  15. Antibacterial, Antioxidant, and Anticholinesterase Activities of Plant Seed Extracts from Brazilian Semiarid Region

    OpenAIRE

    Davi Felipe Farias; Terezinha Maria Souza; Martônio Ponte Viana; Bruno Marques Soares; Arcelina Pacheco Cunha; Ilka Maria Vasconcelos; Nágila Maria Pontes Silva Ricardo; Paulo Michel Pinheiro Ferreira; Vânia Maria Maciel Melo; Ana Fontenele Urano Carvalho

    2013-01-01

    The antimicrobial, antioxidant, and anticholinesterase activities of ethanolic seed extracts of twenty-one plant species from Brazilian semiarid region were investigated. The extracts were tested for antimicrobial activity against six bacteria strains and three yeasts. Six extracts presented activity against the Gram (−) organism Salmonella choleraesuis and the Gram (+) organisms Staphylococcus aureus and Bacillus subtilis. The MIC values ranged from 4.96 to 37.32 mg/mL. The Triplaris gardner...

  16. Statins attenuate polymethylmethacrylate-mediated monocyte activation.

    LENUS (Irish Health Repository)

    Laing, Alan J

    2012-02-03

    BACKGROUND: Periprosthetic osteolysis precipitates aseptic loosening of components, increases the risk of periprosthetic fracture and, through massive bone loss, complicates revision surgery and ultimately is the primary cause for failure of joint arthroplasty. The anti-inflammatory properties of HMG-CoA reductase inhibitors belonging to the statin family are well recognized. We investigated a possible role for status in initiating the first stage of the osteolytic cycle, namely monocytic activation. METHODS: We used an in vitro model of the human monocyte\\/macrophage inflammatory response to poly-methylmethacrylate (PMMA) particles after pretreat-ing cells with cerivastatin, a potent member of the statin family. Cell activation based upon production of TNF-alpha and MCP-1 cytokines was analyzed and the intracellular Raf-MEK-ERK signal transduction pathway was evaluated using western blot analysis, to identify its role in cell activation and in any cerivastatin effects observed. RESULTS: We found that pretreatment with cerivastatin significantly abrogates the production of inflammatory cytokines TNF-alpha and MCP-1 by human monocytes in response to polymethylmethacrylate particle activation. This inflammatory activation and attenuation appear to be mediated through the intracellular Raf-MEK-ERK pathway. INTERPRETATION: We propose that by intervening at the upstream activation stage, subsequent osteoclast activation and osteolysis can be suppressed. We believe that the anti-inflammatory properties of statins may potentially play a prophylactic role in the setting of aseptic loosening, and in so doing increase implant longevity.

  17. SadA, a trimeric autotransporter from Salmonella enterica serovar Typhimurium, can promote biofilm formation and provides limited protection against infection.

    Science.gov (United States)

    Raghunathan, Dhaarini; Wells, Timothy J; Morris, Faye C; Shaw, Robert K; Bobat, Saeeda; Peters, Sarah E; Paterson, Gavin K; Jensen, Karina Tveen; Leyton, Denisse L; Blair, Jessica M A; Browning, Douglas F; Pravin, John; Flores-Langarica, Adriana; Hitchcock, Jessica R; Moraes, Claudia T P; Piazza, Roxane M F; Maskell, Duncan J; Webber, Mark A; May, Robin C; MacLennan, Calman A; Piddock, Laura J; Cunningham, Adam F; Henderson, Ian R

    2011-11-01

    Salmonella enterica is a major cause of morbidity worldwide and mortality in children and immunocompromised individuals in sub-Saharan Africa. Outer membrane proteins of Salmonella are of significance because they are at the interface between the pathogen and the host, they can contribute to adherence, colonization, and virulence, and they are frequently targets of antibody-mediated immunity. In this study, the properties of SadA, a purported trimeric autotransporter adhesin of Salmonella enterica serovar Typhimurium, were examined. We demonstrated that SadA is exposed on the Salmonella cell surface in vitro and in vivo during infection of mice. Expression of SadA resulted in cell aggregation, biofilm formation, and increased adhesion to human intestinal Caco-2 epithelial cells. Immunization of mice with folded, full-length, purified SadA elicited an IgG response which provided limited protection against bacterial challenge. When anti-SadA IgG titers were enhanced by administering alum-precipitated protein, a modest additional protection was afforded. Therefore, despite SadA having pleiotropic functions, it is not a dominant, protective antigen for antibody-mediated protection against Salmonella.

  18. Diversity and antimicrobial susceptibility of Salmonella enterica serovars isolated from pig farms in Ibadan, Nigeria

    DEFF Research Database (Denmark)

    Fashae, Kayode; Hendriksen, Rene S.

    2014-01-01

    of plasmid-mediated quinolone resistance (PMQR) genes in pigs in Ibadan, Nigeria. Pooled fresh pen floor fecal samples of pigs collected from 31 pig farms were cultured; the Salmonella isolates were serotyped and their antimicrobial susceptibility was determined. PMQR genes were screened by polymerase chain...... Kingston (n = 13; 5.7 %). The most widely distributed serovars among the farms were Salmonella Give (six farms) and Salmonella Elisaberthville (six farms). Resistance to chloramphenicol, sulfonamides, nalidixic acid, streptomycin, and tetracycline ranged from 11.6 % (n = 26) to 22.8 % (n = 51). Resistance....... Other PMQR genes were not detected. Pigs constitute an important source of diverse Salmonella serovars in Ibadan. The isolates were more resistant to old antimicrobials with some multiple resistant. Control measures and regulation of antimicrobials are warranted....

  19. Brucella lipopolysaccharide reinforced Salmonella delivering Brucella immunogens protects mice against virulent challenge.

    Science.gov (United States)

    Lalsiamthara, Jonathan; Lee, John Hwa

    2017-06-01

    Intracellular pathogen Salmonella exhibits natural infection broadly analogous to Brucella, this phenomenon makes Salmonella a pragmatic choice for an anti-Brucella vaccine delivery platform. In this study we developed and formulated a combination of four attenuated Salmonella Typhimurium live vector strains delivering heterologous Brucella antigens (rBs), namely lumazine synthase, proline racemase subunit A, lipoprotein outer membrane protein-19, and Cu-Zn superoxide dismutase. With an aim to develop a cross-protecting vaccine, Brucella pan-species conserved rBs were selected. The present study compared the efficacy of smooth and rough variants of Salmonella delivery vector and also evaluated the inclusion of purified Brucella lipopolysaccharide (LPS) in the formulation. Immunization of SPF-BALB/c mice with the vaccine combinations significantly (P≤0.05) reduced splenic wild-type Brucella abortus 544 colonization as compared to non-immunized mice as well as Salmonella only immunized mice. Increased induction of Brucella specific-IgG, sIgA production, and antigen-specific splenocyte proliferative responses were observed in the mice immunized with the formulations as compared to naïve or vector only immunized mice. Modulatory effects of rB and LPS on production of interleukin (IL)-4, IL-12, and interferon-γ were detected in splenocytes of mice immunized with the formulation. Rough Salmonella variant in combination with LPS could further enhance the efficacy of the delivery when applied intraperitoneally. Taken together, it is compelling that Brucella LPS-augmented Salmonella vector delivering immunogenic Brucella proteins may be more suitable than the current non-ideal live Brucella abortus vaccine. The vaccine system also provides a basis for the development of cross-protecting vaccine capable of preventing multispecies brucellosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Inhibitory Effects of Several Essential Oils towards Salmonella typhimurium, Salmonella paratyphi A and Salmonella paratyphi B

    Directory of Open Access Journals (Sweden)

    S.F. Mazhar

    2014-09-01

    Full Text Available Plant essential oils are natural products extracted from plants and because of their antimicrobial properties can be used as natural additives in foods. They are also useful for decontamination of food-borne pathogens and can be a safe additive in foods. The antimicrobial activities of essential oils belonging to Saturiea hortensis, Thymus vulgaris, Mentha polegium, Cuminum cyminum, Lavandula officinalis and Mentha viridis L. (spearmint were investigated at different concentrations (0.1, 0.3, 0.5, 1, 2, 5 and 10%v/v against Salmonella typhimurium, Salmonella paratyphi A and Salmonella paratyphi B by using the agar well diffusion method. Essential oils showed inhibitory effect on Salmonella spp. in the agar well diffusion assay. In addition, the capability of essential oils for decontamination of minced row beef, ground beef, minced raw chicken and minced raw fish inoculated with Salmonella spp. at 0.1 and 0.5%v/v were assessed. Reduction of the Salmonella spp. population was observed following the inoculation of the cultures with 0.1 and 0.5%v/v essential oils.

  1. Development of a novel in-water vaccination protocol for DNA adenine methylase deficient Salmonella enterica serovar Typhimurium vaccine in adult sheep.

    Science.gov (United States)

    Mohler, V L; Heithoff, D M; Mahan, M J; Hornitzky, M A; Thomson, P C; House, J K

    2012-02-14

    Intensive livestock production is associated with an increased incidence of salmonellosis. The risk of infection and the subsequent public health concern is attributed to increased pathogen exposure and disease susceptibility due to multiple stressors experienced by livestock from farm to feedlot. Traditional parenteral vaccine methods can further stress susceptible populations and cause carcass damage, adverse reactions, and resultant increased production costs. As a potential means to address these issues, in-water delivery of live attenuated vaccines affords a low cost, low-stress method for immunization of livestock populations that is not associated with the adverse handling stressors and injection reactions associated with parenteral administration. We have previously established that in-water administration of a Salmonella enterica serovar Typhimurium dam vaccine conferred significant protection in livestock. While these experimental trials hold significant promise, the ultimate measure of the vaccine will not be established until it has undergone clinical testing in the field wherein environmental and sanitary conditions are variable. Here we show that in-water administration of a S. Typhimurium dam attenuated vaccine was safe, stable, and well-tolerated in adult sheep. The dam vaccine did not alter water consumption or vaccine dosing; remained viable under a wide range of temperatures (21-37°C); did not proliferate within fecal-contaminated trough water; and was associated with minimal fecal shedding and clinical disease as a consequence of vaccination. The capacity of Salmonella dam attenuated vaccines to be delivered in drinking water to protect livestock from virulent Salmonella challenge offers an effective, economical, stressor-free Salmonella prophylaxis for intensive livestock production systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Comparisons of Salmonella conjugation and virulence gene hyperexpression mediated by rumen protozoa from domestic and exotic ruminants.

    Science.gov (United States)

    Brewer, Matt T; Xiong, Nalee; Dier, Jeffery D; Anderson, Kristi L; Rasmussen, Mark A; Franklin, Sharon K; Carlson, Steve A

    2011-08-05

    Recent studies have identified a phenomenon in which ciliated protozoa engulf Salmonella and the intra-protozoal environment hyperactivates virulence gene expression and provides a venue for conjugal transfer of antibiotic resistance plasmids. The former observation is relegated to Salmonella bearing the SGI1 multiresistance integron while the latter phenomenon appears to be a more generalized event for recipient Salmonella. Our previous studies have assessed virulence gene hyperexpression only with protozoa from the bovine rumen while conjugal transfer has been demonstrated in rumen protozoa from cattle and goats. The present study examined virulence gene hyperexpression for Salmonella exposed to rumen protozoa obtained from cattle, sheep, goats, or two African ruminants (giraffe and bongo). Conjugal transfer was also assessed in these protozoa using Salmonella as the recipient. Virulence gene hyperexpression was only observed following exposure to the rumen protozoa from cattle and sheep while elevated virulence was also observed in these animals. Conjugal transfer events were, however, observed in all protozoa evaluated. It therefore appears that the protozoa-based hypervirulence is not universal to all ruminants while conjugal transfer is more ubiquitous. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Influence of On-farm pig Salmonella status on Salmonella Shedding at Slaughter.

    Science.gov (United States)

    Casanova-Higes, A; Andrés-Barranco, S; Mainar-Jaime, R C

    2017-08-01

    The risk of Salmonella shedding among pigs at slaughter with regard to their previous on-farm Salmonella status was assessed in a group of pigs from a farm from NE of Spain. A total of 202 pigs that had been serologically monitored monthly during the fattening period and from which mesenteric lymph nodes (MLN) and faecal (SFEC) samples were collected at slaughter for Salmonella isolation were included. A repeated-measures anova was used to assess the relationship between mean OD% values during the fattening period and sampling time and bacteriology on MLN and SFEC. Pigs were also grouped into four groups, that is pigs seronegative during the fattening period and Salmonella negative in MLN (group A; n = 69); pigs seronegative during the fattening period but Salmonella positive in MLN (B; n = 36); pigs seropositive at least once and Salmonella positive in MLN (C; n = 50); and pigs seropositive at least once but Salmonella negative in (D; n = 47). Pigs shedding at slaughter seroconverted much earlier and showed much higher mean OD% values than non-shedders pigs. The proportion of Salmonella shedders in groups A and D was high and similar (26.1% and 29.8%, respectively), but significantly lower than that for groups B and C. The odds of shedding Salmonella for groups B and C were 4.8 (95% CI = 1.5-15.5) and 20.9 (3.7-118) times higher, respectively, when compared to A. It was concluded that a large proportion of Salmonella seronegative pigs may shed Salmonella at slaughter, which would be likely associated to previous exposure with contaminated environments (i.e. transport and lairage). For pigs already infected at farm, the likelihood of shedding Salmonella was much higher and may depend on whether the bacterium has colonized the MLN or not. The odds of shedding Salmonella spp. were always much higher for pigs in which Salmonella was isolated from MLN. © 2016 Blackwell Verlag GmbH.

  4. Safety and tolerability of a live oral Salmonella typhimurium vaccine candidate in SIV-infected nonhuman primates.

    Science.gov (United States)

    Ault, Alida; Tennant, Sharon M; Gorres, J Patrick; Eckhaus, Michael; Sandler, Netanya G; Roque, Annelys; Livio, Sofie; Bao, Saran; Foulds, Kathryn E; Kao, Shing-Fen; Roederer, Mario; Schmidlein, Patrick; Boyd, Mary Adetinuke; Pasetti, Marcela F; Douek, Daniel C; Estes, Jacob D; Nabel, Gary J; Levine, Myron M; Rao, Srinivas S

    2013-12-02

    Nontyphoidal Salmonella (NTS) serovars are a common cause of acute food-borne gastroenteritis worldwide and can cause invasive systemic disease in young infants, the elderly, and immunocompromised hosts, accompanied by high case fatality. Vaccination against invasive NTS disease is warranted where the disease incidence and mortality are high and multidrug resistance is prevalent, as in sub-Saharan Africa. Live-attenuated vaccines that mimic natural infection constitute one strategy to elicit protection. However, they must particularly be shown to be adequately attenuated for consideration of immunocompromised subjects. Accordingly, we examined the safety and tolerability of an oral live attenuated Salmonella typhimurium vaccine candidate, CVD 1921, in an established chronic simian immunodeficiency virus (SIV)-infected rhesus macaque model. We evaluated clinical parameters, histopathology, and measured differences in mucosal permeability to wild-type and vaccine strains. Compared to the wild-type S. typhimurium strain I77 in both SIV-infected and SIV-uninfected nonhuman primate hosts, this live-attenuated vaccine shows reduced shedding and systemic spread, exhibits limited pathological disease manifestations in the digestive tract, and induces low levels of cellular infiltration in tissues. Furthermore, wild-type S. typhimurium induces increased intestinal epithelial damage and permeability, with infiltration of neutrophils and macrophages in both SIV-infected and SIV-uninfected nonhuman primates compared to the vaccine strain. Based on shedding, systemic spread, and histopathology, the live-attenuated S. typhimurium strain CVD 1921 appears to be safe and well-tolerated in the nonhuman primate model, including chronically SIV-infected rhesus macaques. Copyright © 2013. Published by Elsevier Ltd.

  5. Comparative Genomics of 28 Salmonella enterica Isolates: Evidence for CRISPR-Mediated Adaptive Sublineage Evolution ▿†

    Science.gov (United States)

    Fricke, W. Florian; Mammel, Mark K.; McDermott, Patrick F.; Tartera, Carmen; White, David G.; LeClerc, J. Eugene; Ravel, Jacques; Cebula, Thomas A.

    2011-01-01

    Despite extensive surveillance, food-borne Salmonella enterica infections continue to be a significant burden on public health systems worldwide. As the S. enterica species comprises sublineages that differ greatly in antigenic representation, virulence, and antimicrobial resistance phenotypes, a better understanding of the species' evolution is critical for the prediction and prevention of future outbreaks. The roles that virulence and resistance phenotype acquisition, exchange, and loss play in the evolution of S. enterica sublineages, which to a certain extent are represented by serotypes, remains mostly uncharacterized. Here, we compare 17 newly sequenced and phenotypically characterized nontyphoidal S. enterica strains to 11 previously sequenced S. enterica genomes to carry out the most comprehensive comparative analysis of this species so far. These phenotypic and genotypic data comparisons in the phylogenetic species context suggest that the evolution of known S. enterica sublineages is mediated mostly by two mechanisms, (i) the loss of coding sequences with known metabolic functions, which leads to functional reduction, and (ii) the acquisition of horizontally transferred phage and plasmid DNA, which provides virulence and resistance functions and leads to increasing specialization. Matches between S. enterica clustered regularly interspaced short palindromic repeats (CRISPR), part of a defense mechanism against invading plasmid and phage DNA, and plasmid and prophage regions suggest that CRISPR-mediated immunity could control short-term phenotype changes and mediate long-term sublineage evolution. CRISPR analysis could therefore be critical in assessing the evolutionary potential of S. enterica sublineages and aid in the prediction and prevention of future S. enterica outbreaks. PMID:21602358

  6. Effective cancer vaccine platform based on attenuated salmonella and a type III secretion system.

    Science.gov (United States)

    Xu, Xin; Hegazy, Wael A H; Guo, Linjie; Gao, Xiuhua; Courtney, Amy N; Kurbanov, Suhrab; Liu, Daofeng; Tian, Gengwen; Manuel, Edwin R; Diamond, Don J; Hensel, Michael; Metelitsa, Leonid S

    2014-11-01

    Vaccines explored for cancer therapy have been based generally on injectable vector systems used to control foreign infectious pathogens, to which the immune system evolved to respond naturally. However, these vectors may not be effective at presenting tumor-associated antigens (TAA) to the immune system in a manner that is sufficient to engender antitumor responses. We addressed this issue with a novel orally administered Salmonella-based vector that exploits a type III secretion system to deliver selected TAA in the cytosol of professional antigen-presenting cells in situ. A systematic comparison of candidate genes from the Salmonella Pathogenicity Island 2 (SPI2) locus was conducted in the vaccine design, using model antigens and a codon-optimized form of the human TAA survivin (coSVN), an oncoprotein that is overexpressed in most human cancers. In a screen of 20 SPI2 promoter:effector combinations, a PsifB::sseJ combination exhibited maximal potency for antigen translocation into the APC cytosol, presentation to CD8 T cells, and murine immunogenicity. In the CT26 mouse model of colon carcinoma, therapeutic vaccination with a lead PsifB::sseJ-coSVN construct (p8032) produced CXCR3-dependent infiltration of tumors by CD8 T cells, reversed the CD8:Treg ratio at the tumor site, and triggered potent antitumor activity. Vaccine immunogenicity and antitumor potency were enhanced by coadministration of the natural killer T-cell ligand 7DW8-5, which heightened the production of IL12 and IFNγ. Furthermore, combined treatment with p8032 and 7DW8-5 resulted in complete tumor regression in A20 lymphoma-bearing mice, where protective memory was demonstrated. Taken together, our results demonstrate how antigen delivery using an oral Salmonella vector can provide an effective platform for the development of cancer vaccines. ©2014 American Association for Cancer Research.

  7. Safety and immunogenicity of an oral DNA vaccine encoding Sip of Streptococcus agalactiae from Nile tilapia Oreochromis niloticus delivered by live attenuated Salmonella typhimurium.

    Science.gov (United States)

    Huang, L Y; Wang, K Y; Xiao, D; Chen, D F; Geng, Y; Wang, J; He, Y; Wang, E L; Huang, J L; Xiao, G Y

    2014-05-01

    Attenuated Salmonella typhimurium SL7207 was used as a carrier for a reconstructed DNA vaccine against Streptococcus agalactiae. A 1.02 kb DNA fragment, encoding for a portion of the surface immunogenic protein (Sip) of S. agalactiae was inserted into pVAX1. The recombinant plasmid pVAX1-sip was transfected in EPC cells to detect the transient expression by an indirect immunofluorescence assay, together with Western blot analysis. The pVAX1-sip was transformed by electroporation into SL7207. The stability of pVAX1-sip into Salmonella was over 90% after 50 generations with antibiotic selection in vitro while remained stable over 80% during 35 generations under antibiotic-free conditions. The LD50 of SL/pVAX1-sip was 1.7 × 10(11) CFU/fish by intragastric administration which indicated a quite low virulence. Tilapias were inoculated orally at 10(8) CFU/fish, the recombinant bacteria were found present in intestinal tract, spleens and livers and eventually eliminated from the tissues 4 weeks after immunization. Fish immunized at 10(7), 10(8) and 10(9) CFU/fish with different immunization times caused various levels of serum antibody and an effective protection against lethal challenge with the wild-type strain S. agalactiae. Integration studies showed that the pVAX1-sip did not integrate with tilapia chromosomes. The DNA vaccine SL/pVAX1-sip was proved to be safe and effective in protecting tilapias against S. agalactiae infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. The stability of complement-mediated bactericidal activity in human serum against Salmonella.

    Directory of Open Access Journals (Sweden)

    Colette M O'Shaughnessy

    Full Text Available The complement cascade includes heat-labile proteins and care is required when handling serum in order to preserve its functional integrity. We have previously used a whole human serum bactericidal assay to show that antibody and an intact complement system are required in blood for killing of invasive isolates of Salmonella. The aim of the present study was to evaluate the conditions under which human serum can be stored and manipulated while maintaining complement integrity. Serum bactericidal activity against Salmonella was maintained for a minimum of 35 days when stored at 4°C, eight days at 22°C and 54 hours at 37°C. Up to three freeze-thaw cycles had no effect on the persistence of bactericidal activity and hemolytic complement assays confirmed no effect on complement function. Delay in the separation of serum for up to four days from clotted blood stored at 22°C did not affect bactericidal activity. Dilution of serum resulted in an increased rate of loss of bactericidal activity and so serum should be stored undiluted. These findings indicate that the current guidelines concerning manipulation and storage of human serum to preserve complement integrity and function leave a large margin for safety with regards to bactericidal activity against Salmonella. The study provides a scheme for determining the requirements for serum handling in relation to functional activity of complement in other systems.

  9. Use of a recombinant Salmonella enterica serovar Typhimurium strain expressing C-Raf for protection against C-Raf induced lung adenoma in mice

    International Nuclear Information System (INIS)

    Gentschev, Ivaylo; Fensterle, Joachim; Schmidt, Andreas; Potapenko, Tamara; Troppmair, Jakob; Goebel, Werner; Rapp, Ulf R

    2005-01-01

    Serine-threonine kinases of the Raf family (A-Raf, B-Raf, C-Raf) are central players in cellular signal transduction, and thus often causally involved in the development of cancer when mutated or over-expressed. Therefore these proteins are potential targets for immunotherapy and a possible basis for vaccine development against tumors. In this study we analyzed the functionality of a new live C-Raf vaccine based on an attenuated Salmonella enterica serovar Typhimurium aroA strain in two Raf dependent lung tumor mouse models. The antigen C-Raf has been fused to the C-terminal secretion signal of Escherichia coli α-hemolysin and expressed in secreted form by an attenuated aroA Salmonella enterica serovar Typhimurium strain via the α-hemolysin secretion pathway. The effect of the immunization with this recombinant C-Raf strain on wild-type C57BL/6 or lung tumor bearing transgenic BxB mice was analyzed using western blot and FACS analysis as well as specific tumor growth assays. C-Raf antigen was successfully expressed in secreted form by an attenuated Salmonella enterica serovar Typhimurium aroA strain using the E. coli hemolysin secretion system. Immunization of wild-type C57BL/6 or tumor bearing mice provoked specific C-Raf antibody and T-cell responses. Most importantly, the vaccine strain significantly reduced tumor growth in two transgenic mouse models of Raf oncogene-induced lung adenomas. The combination of the C-Raf antigen, hemolysin secretion system and Salmonella enterica serovar Typhimurium could form the basis for a new generation of live bacterial vaccines for the treatment of Raf dependent human malignancies

  10. Eleventh CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp.

    NARCIS (Netherlands)

    Berk PA; Maas HME; de Pinna E; Mooijman KA; MGB

    2006-01-01

    Het elfde ringonderzoek voor de typering van Salmonella werd in maart 2006 georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) in samenwerking met de Health Protection Agency (HPA, Londen, Verenigd Koninkrijk). 26 Nationale Referentie

  11. A lab-on-a-chip system with integrated sample preparation and loop-mediated isothermal amplification for rapid and quantitative detection of Salmonella spp. in food samples

    DEFF Research Database (Denmark)

    Sun, Yi; Than Linh, Quyen; Hung, Tran Quang

    2015-01-01

    was capable to detect Salmonella at concentration of 50 cells per test within 40 min. The simple design, together with high level of integration, isothermal amplification, and quantitative analysis of multiple samples in short time will greatly enhance the practical applicability of the LOC system for rapid...... amplification (LAMP) for rapid and quantitative detection of Salmonella spp. in food samples. The whole diagnostic procedures including DNA isolation, isothermal amplification, and real-time detection were accomplished in a single chamber. Up to eight samples could be handled simultaneously and the system...... and usually take a few hours to days to complete. In response to the demand for rapid on line or at site detection of pathogens, in this study, we describe for the first time an eight-chamber lab-on-a-chip (LOC) system with integrated magnetic beads-based sample preparation and loop-mediated isothermal...

  12. Salmonella infection inhibits intestinal biotin transport: cellular and molecular mechanisms.

    Science.gov (United States)

    Ghosal, Abhisek; Jellbauer, Stefan; Kapadia, Rubina; Raffatellu, Manuela; Said, Hamid M

    2015-07-15

    Infection with the nontyphoidal Salmonella is a common cause of food-borne disease that leads to acute gastroenteritis/diarrhea. Severe/prolonged cases of Salmonella infection could also impact host nutritional status, but little is known about its effect on intestinal absorption of vitamins, including biotin. We examined the effect of Salmonella enterica serovar Typhimurium (S. typhimurium) infection on intestinal biotin uptake using in vivo (streptomycin-pretreated mice) and in vitro [mouse (YAMC) and human (NCM460) colonic epithelial cells, and human intestinal epithelial Caco-2 cells] models. The results showed that infecting mice with wild-type S. typhimurium, but not with its nonpathogenic isogenic invA spiB mutant, leads to a significant inhibition in jejunal/colonic biotin uptake and in level of expression of the biotin transporter, sodium-dependent multivitamin transporter. In contrast, infecting YAMC, NCM460, and Caco-2 cells with S. typhimurium did not affect biotin uptake. These findings suggest that the effect of S. typhimurium infection is indirect and is likely mediated by proinflammatory cytokines, the levels of which were markedly induced in the intestine of S. typhimurium-infected mice. Consistent with this hypothesis, exposure of NCM460 cells to the proinflammatory cytokines TNF-α and IFN-γ led to a significant inhibition of biotin uptake, sodium-dependent multivitamin transporter expression, and activity of the SLC5A6 promoter. The latter effects appear to be mediated, at least in part, via the NF-κB signaling pathway. These results demonstrate that S. typhimurium infection inhibits intestinal biotin uptake, and that the inhibition is mediated via the action of proinflammatory cytokines.

  13. Tenth CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp.

    NARCIS (Netherlands)

    Korver H; Maas HME; Ward LR; Mevius DJ; Mooijman KA; MGB

    2006-01-01

    Het tiende ringonderzoek voor de typering van Salmonella werd in maart 2005 georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) in samenwerking met de Health Protection Agency (HPA, Londen, Verenigd Koninkrijk) en het Centraal Instituut

  14. Effect of live Salmonella Ty21a in Dextran Sulfate Sodium-induced Colitis

    Directory of Open Access Journals (Sweden)

    Gunnar Nysœter

    2007-01-01

    Full Text Available Background Intestinal microbiota seems to play an essential role in the development of inflammatory bowel diseases (IBD. We hypothesised that an oral vaccine based on live Salmonella typhi would be well tolerated and could even attenuate dextran sulfate sodium (DSS induced colitis in rats, an animal model of IBD. Methods Nine male Wistar rats was used for an initial tolerance study, in which we used 3 dose-levels of Salmonella Ty21a, 0.5 × 10 9 , 1 × 10 9 , and 2 × 10 9 CFU, each dose being tested in 3 rats. Four treatment groups consisting of 8 male Wistar rats per group: 1 control group given standard food and water, 2 control group given four daily administrations of Salmonella Ty21a 1 × 10 9 CFU, 3 water with 5% DSS the last 7 days, 4 four daily administrations of Salmonella Ty21a before water with 5% DSS the last 7 days. The Salmonella Ty21a was administered by gastric gavage on day 1, 3, 5 and 16, while DSS was given with the drinking water from day 15 to 22. The animals were sacrificed and colonic tissue removed for analysis 22 days after gavage of the first vaccine dose. Results The animals in the tolerance study got no signs of disease. In the treatment study, all animals receiving DSS had histologic indications of colitis, particularly in the distal part of the colon. Administration of Salmonella Ty21a had no significant effect on crypt and inflammation scores (p > 0.05. Conclusion Gastric administration of live vaccine strain Salmonella Ty21a was well tolerated, but did not provide any significant protection against development of DSS induced colitis in rats.

  15. Comparison of reverse transcriptase PCR, reverse transcriptase loop-mediated isothermal amplification, and culture-based assays for Salmonella detection from pork processing environments.

    Science.gov (United States)

    Techathuvanan, Chayapa; Draughon, Frances Ann; D'Souza, Doris Helen

    2011-02-01

    Novel rapid Salmonella detection assays without the need for sophisticated equipment or labor remain in high demand. Real-time reverse transcriptase PCR (RT-PCR) assays, though rapid and sensitive, require expensive thermocyclers, while a novel RT loop-mediated isothermal amplification (RT-LAMP) method requires only a simple water bath. Our objective was to compare the detection sensitivity of Salmonella Typhimurium from the pork processing environment by RT-LAMP, RT-PCR, and culture-based assays. Carcass and surface swabs and carcass rinses were obtained from a local processing plant. Autoclaved carcass rinses (500 ml) were spiked with Salmonella Typhimurium and filtered. Filters were placed in stomacher bags containing tetrathionate broth (TTB) and analyzed with or without 10-h enrichment at 37 °C. Natural swabs were stomached with buffered peptone water, and natural carcass rinses were filtered, preenriched, and further enriched in TTB. Serially-diluted enriched samples were enumerated by spread plating on xylose lysine Tergitol 4 agar. RNA was extracted from 5 ml of enriched TTB with TRIzol. RT-LAMP assay using previously described invA primers was conducted at 62 °C for 90 min in a water bath with visual detection and by gel electrophoresis. SYBR Green I-based-real-time RT-PCR was carried out with invA primers followed by melt temperature analysis. The results of RT-LAMP detection for spiked carcass rinses were comparable to those of RT-PCR and cultural plating, with detection limits of 1 log CFU/ml, although they were obtained significantly faster, within 24 h including preenrichment and enrichment. RT-LAMP showed 4 of 12 rinse samples positive, while RT-PCR showed 1 of 12 rinse samples positive. For swabs, 6 of 27 samples positive by RT-LAMP and 5 of 27 by RT-PCR were obtained. This 1-day RT-LAMP assay shows promise for routine Salmonella screening by the pork industry. Copyright ©, International Association for Food Protection

  16. SadA, a Trimeric Autotransporter from Salmonella enterica Serovar Typhimurium, Can Promote Biofilm Formation and Provides Limited Protection against Infection ▿ †

    Science.gov (United States)

    Raghunathan, Dhaarini; Wells, Timothy J.; Morris, Faye C.; Shaw, Robert K.; Bobat, Saeeda; Peters, Sarah E.; Paterson, Gavin K.; Jensen, Karina Tveen; Leyton, Denisse L.; Blair, Jessica M. A.; Browning, Douglas F.; Pravin, John; Flores-Langarica, Adriana; Hitchcock, Jessica R.; Moraes, Claudia T. P.; Piazza, Roxane M. F.; Maskell, Duncan J.; Webber, Mark A.; May, Robin C.; MacLennan, Calman A.; Piddock, Laura J.; Cunningham, Adam F.; Henderson, Ian R.

    2011-01-01

    Salmonella enterica is a major cause of morbidity worldwide and mortality in children and immunocompromised individuals in sub-Saharan Africa. Outer membrane proteins of Salmonella are of significance because they are at the interface between the pathogen and the host, they can contribute to adherence, colonization, and virulence, and they are frequently targets of antibody-mediated immunity. In this study, the properties of SadA, a purported trimeric autotransporter adhesin of Salmonella enterica serovar Typhimurium, were examined. We demonstrated that SadA is exposed on the Salmonella cell surface in vitro and in vivo during infection of mice. Expression of SadA resulted in cell aggregation, biofilm formation, and increased adhesion to human intestinal Caco-2 epithelial cells. Immunization of mice with folded, full-length, purified SadA elicited an IgG response which provided limited protection against bacterial challenge. When anti-SadA IgG titers were enhanced by administering alum-precipitated protein, a modest additional protection was afforded. Therefore, despite SadA having pleiotropic functions, it is not a dominant, protective antigen for antibody-mediated protection against Salmonella. PMID:21859856

  17. A novel Salmonella serovar isolated from Peregrine Falcon (Falco peregrinus nestlings in Sweden: Salmonella enterica enterica serovar Pajala (Salmonella Pajala

    Directory of Open Access Journals (Sweden)

    Jorge Hernández

    2012-08-01

    Full Text Available A novel Salmonella serovar was isolated from Peregrine falcon (Falco peregrinus nestlings in northern Sweden in 2006. Three isolates of the same clone was retrieved from three falcon siblings and characterized as Salmonella enterica sub-species enterica: O-phase 13, 23:-: e, n, z 15 and the H-phase was not present. We propose the geographical name Salmonella enterica, sub-species enterica serovar Pajala to this novel Salmonella.

  18. 15-Deoxy-Δ12,14-prostaglandin J2 inhibits macrophage colonization by Salmonella enterica serovar Typhimurium.

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    Michelle M C Buckner

    Full Text Available 15-deoxy-Δ(12,14-prostaglandin J2 (15d-PGJ2 is an anti-inflammatory downstream product of the cyclooxygenase enzymes. It has been implicated to play a protective role in a variety of inflammatory mediated diseases, including rheumatoid arthritis, neural damage, and myocardial infarctions. Here we show that 15d-PGJ2 also plays a role in Salmonella infection. Salmonella enterica Typhimurium is a Gram-negative facultative intracellular pathogen that is able to survive and replicate inside phagocytic immune cells, allowing for bacterial dissemination to systemic sites. Salmonella species cause a wide range of morbidity and mortality due to gastroenteritis and typhoid fever. Previously we have shown that in mouse models of typhoid fever, Salmonella infection causes a major perturbation in the prostaglandin pathway. Specifically, we saw that 15d-PGJ2 production was significantly increased in both liver and feces. In this work we show that 15d-PGJ2 production is also significantly increased in macrophages infected with Salmonella. Furthermore, we show that the addition of 15d-PGJ2 to Salmonella infected RAW264.7, J774, and bone marrow derived macrophages is sufficient to significantly reduce bacterial colonization. We also show evidence that 15d-PGJ2 is reducing bacterial uptake by macrophages. 15d-PGJ2 reduces the inflammatory response of these infected macrophages, as evidenced by a reduction in the production of cytokines and reactive nitrogen species. The inflammatory response of the macrophage is important for full Salmonella virulence, as it can give the bacteria cues for virulence. The reduction in bacterial colonization is independent of the expression of Salmonella virulence genes SPI1 and SPI2, and is independent of the 15d-PGJ2 ligand PPAR-γ. 15d-PGJ2 also causes an increase in ERK1/2 phosphorylation in infected macrophages. In conclusion, we show here that 15d-PGJ2 mediates the outcome of bacterial infection, a previously unidentified

  19. A Multi-Omic View of Host-Pathogen-Commensal Interplay in Salmonella-Mediated Intestinal Infection

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Brooke LD; Li, Jie; Sanford, James A.; Kim, Young-Mo; Kronewitter, Scott R.; Jones, Marcus B.; Peterson, Christine; Peterson, Scott N.; Frank, Bryan C.; Purvine, Samuel O.; Brown, Joseph N.; Metz, Thomas O.; Smith, Richard D.; Heffron, Fred; Adkins, Joshua N.

    2013-06-26

    The potential for commensal microorganisms indigenous to a host (the ‘microbiome’ or ‘microbiota’) to alter infection outcome by influencing host-pathogen interplay is largely unknown. We used a multi-omics “systems” approach, incorporating proteomics, metabolomics, glycomics, and metagenomics, to explore the molecular interplay between the murine host, the pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium), and commensal gut microorganisms during intestinal infection with S. Typhimurium. We find proteomic evidence that S. Typhimurium thrives within the infected 129/SvJ mouse gut without antibiotic pre-treatment, inducing inflammation and disrupting the intestinal microbiome (e.g., suppressing Bacteroidetes and Firmicutes while promoting growth of Salmonella and Enterococcus). Alteration of the host microbiome population structure was highly correlated with gut environmental changes, including the accumulation of metabolites normally consumed by commensal microbiota. Finally, the less characterized phase of S. Typhimurium’s lifecycle was investigated, and both proteomic and glycomic evidence suggests S. Typhimurium may take advantage of increased fucose moieties to metabolize fucose while growing in the gut. The application of multiple omics measurements to Salmonella-induced intestinal inflammation provides insights into complex molecular strategies employed during pathogenesis between host, pathogen, and the microbiome.

  20. Locus Coeruleus and Tuberomammillary Nuclei Ablations Attenuate Hypocretin/Orexin Antagonist-Mediated REM Sleep.

    Science.gov (United States)

    Schwartz, Michael D; Nguyen, Alexander T; Warrier, Deepti R; Palmerston, Jeremiah B; Thomas, Alexia M; Morairty, Stephen R; Neylan, Thomas C; Kilduff, Thomas S

    2016-01-01

    Hypocretin 1 and 2 (Hcrts; also known as orexin A and B), excitatory neuropeptides synthesized in cells located in the tuberal hypothalamus, play a central role in the control of arousal. Hcrt inputs to the locus coeruleus norepinephrine (LC NE) system and the posterior hypothalamic histaminergic tuberomammillary nuclei (TMN HA) are important efferent pathways for Hcrt-induced wakefulness. The LC expresses Hcrt receptor 1 (HcrtR1), whereas HcrtR2 is found in the TMN. Although the dual Hcrt/orexin receptor antagonist almorexant (ALM) decreases wakefulness and increases NREM and REM sleep time, the neural circuitry that mediates these effects is currently unknown. To test the hypothesis that ALM induces sleep by selectively disfacilitating subcortical wake-promoting populations, we ablated LC NE neurons (LCx) or TMN HA neurons (TMNx) in rats using cell-type-specific saporin conjugates and evaluated sleep/wake following treatment with ALM and the GABAA receptor modulator zolpidem (ZOL). Both LCx and TMNx attenuated the promotion of REM sleep by ALM without affecting ALM-mediated increases in NREM sleep. Thus, eliminating either HcrtR1 signaling in the LC or HcrtR2 signaling in the TMN yields similar effects on ALM-induced REM sleep without affecting NREM sleep time. In contrast, neither lesion altered ZOL efficacy on any measure of sleep-wake regulation. These results contrast with those of a previous study in which ablation of basal forebrain cholinergic neurons attenuated ALM-induced increases in NREM sleep time without affecting REM sleep, indicating that Hcrt neurotransmission influences distinct aspects of NREM and REM sleep at different locations in the sleep-wake regulatory network.

  1. Exercise training attenuates chemoreflex-mediated reductions of renal blood flow in heart failure.

    Science.gov (United States)

    Marcus, Noah J; Pügge, Carolin; Mediratta, Jai; Schiller, Alicia M; Del Rio, Rodrigo; Zucker, Irving H; Schultz, Harold D

    2015-07-15

    In chronic heart failure (CHF), carotid body chemoreceptor (CBC) activity is increased and contributes to increased tonic and hypoxia-evoked elevation in renal sympathetic nerve activity (RSNA). Elevated RSNA and reduced renal perfusion may contribute to development of the cardio-renal syndrome in CHF. Exercise training (EXT) has been shown to abrogate CBC-mediated increases in RSNA in experimental heart failure; however, the effect of EXT on CBC control of renal blood flow (RBF) is undetermined. We hypothesized that CBCs contribute to tonic reductions in RBF in CHF, that stimulation of the CBC with hypoxia would result in exaggerated reductions in RBF, and that these responses would be attenuated with EXT. RBF was measured in CHF-sedentary (SED), CHF-EXT, CHF-carotid body denervation (CBD), and CHF-renal denervation (RDNX) groups. We measured RBF at rest and in response to hypoxia (FiO2 10%). All animals exhibited similar reductions in ejection fraction and fractional shortening as well as increases in ventricular systolic and diastolic volumes. Resting RBF was lower in CHF-SED (29 ± 2 ml/min) than in CHF-EXT animals (46 ± 2 ml/min, P < 0.05) or in CHF-CBD animals (42 ± 6 ml/min, P < 0.05). In CHF-SED, RBF decreased during hypoxia, and this was prevented in CHF-EXT animals. Both CBD and RDNX abolished the RBF response to hypoxia in CHF. Mean arterial pressure increased in response to hypoxia in CHF-SED, but was prevented by EXT, CBD, and RDNX. EXT is effective in attenuating chemoreflex-mediated tonic and hypoxia-evoked reductions in RBF in CHF. Copyright © 2015 the American Physiological Society.

  2. Increase in resistance to extended-spectrum cephalosporins in Salmonella isolated from retail chicken products in Japan.

    Science.gov (United States)

    Noda, Tamie; Murakami, Koichi; Etoh, Yoshiki; Okamoto, Fuyuki; Yatsuyanagi, Jun; Sera, Nobuyuki; Furuta, Munenori; Onozuka, Daisuke; Oda, Takahiro; Asai, Tetsuo; Fujimoto, Shuji

    2015-01-01

    Extended-spectrum β-lactamase (ESBL)-producing Salmonella are one of the most important public health problems in developed countries. ESBL-producing Salmonella strains have been isolated from humans in Asian countries neighboring Japan, along with strains harboring the plasmid-mediated extended-spectrum cephalosporin (ESC)-resistance gene, ampC (pAmpC). However, only a few studies have investigated the prevalence of ESC-resistant Salmonella in chicken products in Japan, which are the main vehicle of Salmonella transmission. The aim of this study was to investigate the prevalence of ESBL-producing, pAmpC-harboring, or carbapenem-resistant Salmonella in chicken products in Japan. In total, 355 out of 779 (45.6%) chicken product samples collected from 1996-2010 contained Salmonella, resulting in 378 distinct isolates. Of these isolates, 373 were tested for resistance to ESCs, cephamycins, or carbapenems. Isolates that showed resistance to one or more of these antimicrobials were then examined by PCR and DNA sequence analysis for the presence of the bla(CMY), bla(CTX-M), bla(TEM), and bla(SHV) resistance genes. Thirty-five resistant isolates were detected, including 26 isolates that contained pAmpC (bla(CMY-2)), and nine ESBL-producing isolates harboring bla(CTX-M) (n = 4, consisting of two bla(CTX-M-2) and two bla(CTX-M-15 genes)), bla(TEM) (n = 4, consisting of one bla(TEM-20) and three bla(TEM-52) genes), and bla(SHV) (n = 1, bla(SHV-12)). All pAmpC-harboring and ESBL-producing Salmonella isolates were obtained from samples collected after 2005, and the percentage of resistant isolates increased significantly from 0% in 2004 to 27.9% in 2010 (P for trend = 0.006). This increase was caused in part by an increase in the number of Salmonella enterica subsp. enterica serovar Infantis strains harboring an approximately 280-kb plasmid containing bla(CMY-2) in proximity to ISEcp1. The dissemination of ESC-resistant Salmonella containing plasmid-mediated bla(CMY-2) in

  3. Increase in resistance to extended-spectrum cephalosporins in Salmonella isolated from retail chicken products in Japan.

    Directory of Open Access Journals (Sweden)

    Tamie Noda

    Full Text Available Extended-spectrum β-lactamase (ESBL-producing Salmonella are one of the most important public health problems in developed countries. ESBL-producing Salmonella strains have been isolated from humans in Asian countries neighboring Japan, along with strains harboring the plasmid-mediated extended-spectrum cephalosporin (ESC-resistance gene, ampC (pAmpC. However, only a few studies have investigated the prevalence of ESC-resistant Salmonella in chicken products in Japan, which are the main vehicle of Salmonella transmission. The aim of this study was to investigate the prevalence of ESBL-producing, pAmpC-harboring, or carbapenem-resistant Salmonella in chicken products in Japan. In total, 355 out of 779 (45.6% chicken product samples collected from 1996-2010 contained Salmonella, resulting in 378 distinct isolates. Of these isolates, 373 were tested for resistance to ESCs, cephamycins, or carbapenems. Isolates that showed resistance to one or more of these antimicrobials were then examined by PCR and DNA sequence analysis for the presence of the bla(CMY, bla(CTX-M, bla(TEM, and bla(SHV resistance genes. Thirty-five resistant isolates were detected, including 26 isolates that contained pAmpC (bla(CMY-2, and nine ESBL-producing isolates harboring bla(CTX-M (n = 4, consisting of two bla(CTX-M-2 and two bla(CTX-M-15 genes, bla(TEM (n = 4, consisting of one bla(TEM-20 and three bla(TEM-52 genes, and bla(SHV (n = 1, bla(SHV-12. All pAmpC-harboring and ESBL-producing Salmonella isolates were obtained from samples collected after 2005, and the percentage of resistant isolates increased significantly from 0% in 2004 to 27.9% in 2010 (P for trend = 0.006. This increase was caused in part by an increase in the number of Salmonella enterica subsp. enterica serovar Infantis strains harboring an approximately 280-kb plasmid containing bla(CMY-2 in proximity to ISEcp1. The dissemination of ESC-resistant Salmonella containing plasmid-mediated bla(CMY-2 in chicken

  4. Comparative study of the protective capacity against Salmonella infection between probiotic and nonprobiotic Lactobacilli.

    Science.gov (United States)

    Castillo, N A; de Moreno de LeBlanc, A; M Galdeano, C; Perdigón, G

    2013-03-01

    To investigate the immunoprotective ability of three Lactobacilli strains against Salmonella enterica serovar Typhimurium in a mouse model. To identify the probiotic properties involved in the protection against infection caused by this pathogen. The immunomodulatory effect of three different lactobacilli strains: Lactobacillus (Lact.) casei CRL 431 (probiotic bacterium), Lact. delbrueckii subsp. bulgaricus CRL 423 (Lact. bulgaricus) and Lact.acidophilus CRL 730 was compared using a mouse model of Salmonella infection. Lactobacillus casei continuous administration improved animal survival, diminished pathogen spreading outside the intestine, attenuated the intestinal inflammation, modulated cytokine profile previous and postinfection and increased the expression and secretion of IgA in the gut. Additionally, the administration of this lactobacilli increased peritoneal, Peyer's patches and spleen macrophages' phagocytic activity in healthy mice and monocyte chemotactic protein (MCP-1) released by intestinal epithelial cells in an in vitro assay. Although Lact. acidophilus increased the number of IgA-secreting cells previous and postinfection, and Lact. bulgaricus increased MCP-1 released by intestinal epithelial cells and the phagocytic activity of macrophages, these effects alone were not enough to confer protection against Salmonella Typhimurium infection in mouse. Probiotic strain Lact. casei CRL 431 was the one that induced protection against Salmonella, by increasing the intestinal barrier function and by decreasing the local inflammatory response. Salmonella spp. constitutes an important agent of foodborne diseases in the world. Not all lactobacilli, even with some immunostimulating properties at gut level, can protect against Salmonella infection. Lactobacillus casei CRL 431, a probiotic bacterium, could be useful as an oral mucosal adjuvant of the immune system to improve gut health, especially in the prevention or amelioration of Salmonella infections. We

  5. Three Phoma spp. synthesised novel silver nanoparticles that possess excellent antimicrobial efficacy.

    Science.gov (United States)

    Rai, Mahendra; Ingle, Avinash P; Gade, Aniket K; Duarte, Marta Cristina Teixeira; Duran, Nelson

    2015-10-01

    The authors report extracellular mycosynthesis of silver nanoparticles (AgNPs) by Phoma capsulatum, Phoma putaminum and Phoma citri. The AgNPs thus synthesised were characterised by UV-visible spectrophotometer, Fourier transform infrared spectroscopy, Nanosight LM20 and transmission electron microscopy, which confirmed the synthesis of mostly spherical and polydisperse nanoparticles capped with proteins. The size of AgNPs was found in the range of 10-80 , 5-80 and 5-90 nm with an average size of 31.85, 25.43 and 23.29 nm by P. capsulatum, P. putaminum and P. citri, respectively. Further, potential antimicrobial activity was reported against Aspergillus niger, Candida albicans, Salmonella choleraesuis, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. The lowest minimal inhibitory concentration (MIC) (0.85 µg/ml) was reported for AgNPs synthesised from P. citri against S. choleraesuis. However, AgNPs synthesised from P. capsulatum showed the highest MIC (10.62 µg/ml) against S. choleraesuis, P. aeruginosa and E. coli (clinical isolate). The same MIC values (10.62 µg/ml) were also reported against P. aeruginosa and both clinical and standard isolates of E. coli for AgNPs synthesised from P. citri. It was also observed that all the silver nanoparticles showed remarkable antifungal and antibacterial activity against these tested pathogens as compared with the commercially available antifungal and antibacterial agents.

  6. Impact of litter Salmonella status during feed withdrawal on Salmonella recovery from the broiler crop and ceca.

    Science.gov (United States)

    Buhr, R J; Bourassa, D V; Hinton, A; Fairchild, B D; Ritz, C W

    2017-12-01

    Research was conducted to evaluate the impact of litter Salmonella status during feed withdrawal on Salmonella recovery from the crop and ceca following feed withdrawal. In 4 experiments, pens of broilers in separate rooms were challenged with marker strains of either Salmonella Montevideo or Salmonella Heidelberg. Three d post challenge, a 12-hour feed withdrawal was initiated, and one pen of broilers was switched between rooms for each Salmonella serotype. In experiments 3 and 4, non-challenged broilers also were added to the Salmonella challenge pens. The litter of each pen was sampled before and after the feed withdrawal period, the broilers euthanized, and the crop and ceca aseptically removed for Salmonella isolation. Results showed that only the challenge Salmonella serotype was recovered from the litter in challenge pens where broilers were not moved, while both Salmonella serotypes were recovered from the litter of the switched pens. Salmonella was recovered from 56/80 crops and from 66/80 ceca of challenged broilers that remained in the challenge pens. The challenge Salmonella serotype was recovered from 50/80 crops and from 60/80 ceca, and the switched pens' litter Salmonella serotype was recovered from 19/80 crops but not from the ceca in broilers challenged with Salmonella and then switched between pens. For experiments 3 and 4, Salmonella was recovered from 19/40 crops and from only 2/40 ceca from the non-challenged broilers placed into the Salmonella challenge pens. The results from broilers that were switched between Salmonella challenge pens indicate that the recovery of Salmonella from the crop of broilers following feed withdrawal (on Salmonella-contaminated litter) appears to depend mainly on the initial challenge Salmonella (62%) and less on the litter Salmonella (24%) status during the feed withdrawal period. In contrast, only the initial challenge Salmonella was recovered from the ceca (79%) from broilers that remained in challenge pens or

  7. Tachykinin NK₁ receptor antagonist co-administration attenuates opioid withdrawal-mediated spinal microglia and astrocyte activation.

    Science.gov (United States)

    Tumati, Suneeta; Largent-Milnes, Tally M; Keresztes, Attila I; Yamamoto, Takashi; Vanderah, Todd W; Roeske, William R; Hruby, Victor J; Varga, Eva V

    2012-06-05

    Prolonged morphine treatment increases pain sensitivity in many patients. Enhanced spinal Substance P release is one of the adaptive changes associated with sustained opioid exposure. In addition to pain transmitting second order neurons, spinal microglia and astrocytes also express functionally active Tachykinin NK₁ (Substance P) receptors. In the present work we investigated the role of glial Tachykinin NK₁ receptors in morphine withdrawal-mediated spinal microglia and astrocyte activation. Our data indicate that intrathecal co-administration (6 days, twice daily) of a selective Tachykinin NK₁ receptor antagonist (N-acetyl-L-tryptophan 3,5-bis(trifluoromethyl)benzylester (L-732,138; 20 μg/injection)) attenuates spinal microglia and astrocyte marker and pro-inflammatory mediator immunoreactivity as well as hyperalgesia in withdrawn rats. Furthermore, covalent linkage of the opioid agonist with a Tachykinin NK₁ antagonist pharmacophore yielded a bivalent compound that did not augment spinal microglia or astrocyte marker or pro-inflammatory mediator immunoreactivity and did not cause paradoxical pain sensitization upon drug withdrawal. Thus, bivalent opioid/Tachykinin NK₁ receptor antagonists may provide a novel paradigm for long-term pain management.

  8. Epidemiology, Clinical Presentation, Laboratory Diagnosis, Antimicrobial Resistance, and Antimicrobial Management of Invasive Salmonella Infections

    Science.gov (United States)

    Sjölund-Karlsson, Maria; Gordon, Melita A.; Parry, Christopher M.

    2015-01-01

    SUMMARY Salmonella enterica infections are common causes of bloodstream infection in low-resource areas, where they may be difficult to distinguish from other febrile illnesses and may be associated with a high case fatality ratio. Microbiologic culture of blood or bone marrow remains the mainstay of laboratory diagnosis. Antimicrobial resistance has emerged in Salmonella enterica, initially to the traditional first-line drugs chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole. Decreased fluoroquinolone susceptibility and then fluoroquinolone resistance have developed in association with chromosomal mutations in the quinolone resistance-determining region of genes encoding DNA gyrase and topoisomerase IV and also by plasmid-mediated resistance mechanisms. Resistance to extended-spectrum cephalosporins has occurred more often in nontyphoidal than in typhoidal Salmonella strains. Azithromycin is effective for the management of uncomplicated typhoid fever and may serve as an alternative oral drug in areas where fluoroquinolone resistance is common. In 2013, CLSI lowered the ciprofloxacin susceptibility breakpoints to account for accumulating clinical, microbiologic, and pharmacokinetic-pharmacodynamic data suggesting that revision was needed for contemporary invasive Salmonella infections. Newly established CLSI guidelines for azithromycin and Salmonella enterica serovar Typhi were published in CLSI document M100 in 2015. PMID:26180063

  9. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

    Directory of Open Access Journals (Sweden)

    Peter J Hart

    Full Text Available Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

  10. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

    Science.gov (United States)

    Hart, Peter J; O'Shaughnessy, Colette M; Siggins, Matthew K; Bobat, Saeeda; Kingsley, Robert A; Goulding, David A; Crump, John A; Reyburn, Hugh; Micoli, Francesca; Dougan, Gordon; Cunningham, Adam F; MacLennan, Calman A

    2016-01-01

    Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

  11. Comparing human-Salmonella with plant-Salmonella protein-protein interaction predictions

    Directory of Open Access Journals (Sweden)

    Sylvia eSchleker

    2015-01-01

    Full Text Available Salmonellosis is the most frequent food-borne disease world-wide and can be transmitted to humans by a variety of routes, especially via animal and plant products. Salmonella bacteria are believed to use not only animal and human but also plant hosts despite their evolutionary distance. This raises the question if Salmonella employs similar mechanisms in infection of these diverse hosts. Given that most of our understanding comes from its interaction with human hosts, we investigate here to what degree knowledge of Salmonella-human interactions can be transferred to the Salmonella-plant system. Reviewed are recent publications on analysis and prediction of Salmonella-host interactomes. Putative protein-protein interactions (PPIs between Salmonella and its human and Arabidopsis hosts were retrieved utilizing purely interolog-based approaches in which predictions were inferred based on available sequence and domain information of known PPIs, and machine learning approaches that integrate a larger set of useful information from different sources. Transfer learning is an especially suitable machine learning technique to predict plant host targets from the knowledge of human host targets. A comparison of the prediction results with transcriptomic data shows a clear overlap between the host proteins predicted to be targeted by PPIs and their gene ontology enrichment in both host species and regulation of gene expression. In particular, the cellular processes Salmonella interferes with in plants and humans are catabolic processes. The details of how these processes are targeted, however, are quite different between the two organisms, as expected based on their evolutionary and habitat differences. Possible implications of this observation on evolution of host-pathogen communication are discussed.

  12. Specific Monoclonal Antibody Overcomes the Salmonella enterica Serovar Typhimurium's Adaptive Mechanisms of Intramacrophage Survival and Replication.

    Directory of Open Access Journals (Sweden)

    Swarmistha Devi Aribam

    Full Text Available Salmonella-specific antibodies play an important role in host immunity; however, the mechanisms of Salmonella clearance by pathogen-specific antibodies remain to be completely elucidated since previous studies on antibody-mediated protection have yielded inconsistent results. These inconsistencies are at least partially attributable to the use of polyclonal antibodies against Salmonella antigens. Here, we developed a new monoclonal antibody (mAb-449 and identified its related immunogen that protected BALB/c mice from infection with Salmonella enterica serovar Typhimurium. In addition, these data indicate that the mAb-449 immunogen is likely a major protective antigen. Using in vitro infection studies, we also analyzed the mechanism by which mAb-449 conferred host protection. Notably, macrophages infected with mAb-449-treated S. Typhimurium showed enhanced pathogen uptake compared to counterparts infected with control IgG-treated bacteria. Moreover, these macrophages produced elevated levels of pro-inflammatory cytokine TNFα and nitric oxide, indicating that mAb-449 enhanced macrophage activation. Finally, the number of intracellular bacteria in mAb-449-activated macrophages decreased considerably, while the opposite was found in IgG-treated controls. Based on these findings, we suggest that, although S. Typhimurium has the potential to survive and replicate within macrophages, host production of a specific antibody can effectively mediate macrophage activation for clearance of intracellular bacteria.

  13. Salmonella risk to consumers via pork is related to the Salmonella prevalence in pig feed.

    Science.gov (United States)

    Rönnqvist, M; Välttilä, V; Ranta, J; Tuominen, P

    2018-05-01

    Pigs are an important source of human infections with Salmonella, one of the most common causes of sporadic gastrointestinal infections and foodborne outbreaks in the European region. Feed has been estimated to be a significant source of Salmonella in piggeries in countries of a low Salmonella prevalence. To estimate Salmonella risk to consumers via the pork production chain, including feed production, a quantitative risk assessment model was constructed. The Salmonella prevalence in feeds and in animals was estimated to be generally low in Finland, but the relative importance of feed as a source of Salmonella in pigs was estimated as potentially high. Discontinuation of the present strict Salmonella control could increase the risk of Salmonella in slaughter pigs and consequent infections in consumers. The increased use of low risk and controlled feed ingredients could result in a consistently lower residual contamination in pigs and help the tracing and control of the sources of infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Attachment of Salmonella strains to a plant cell wall model is modulated by surface characteristics and not by specific carbohydrate interactions.

    Science.gov (United States)

    Tan, Michelle Sze-Fan; Moore, Sean C; Tabor, Rico F; Fegan, Narelle; Rahman, Sadequr; Dykes, Gary A

    2016-09-15

    Processing of fresh produce exposes cut surfaces of plant cell walls that then become vulnerable to human foodborne pathogen attachment and contamination, particularly by Salmonella enterica. Plant cell walls are mainly composed of the polysaccharides cellulose, pectin and hemicelluloses (predominantly xyloglucan). Our previous work used bacterial cellulose-based plant cell wall models to study the interaction between Salmonella and the various plant cell wall components. We demonstrated that Salmonella attachment was favoured in the presence of pectin while xyloglucan had no effect on its attachment. Xyloglucan significantly increased the attachment of Salmonella cells to the plant cell wall model only when it was in association with pectin. In this study, we investigate whether the plant cell wall polysaccharides mediate Salmonella attachment to the bacterial cellulose-based plant cell wall models through specific carbohydrate interactions or through the effects of carbohydrates on the physical characteristics of the attachment surface. We found that none of the monosaccharides that make up the plant cell wall polysaccharides specifically inhibit Salmonella attachment to the bacterial cellulose-based plant cell wall models. Confocal laser scanning microscopy showed that Salmonella cells can penetrate and attach within the tightly arranged bacterial cellulose network. Analysis of images obtained from atomic force microscopy revealed that the bacterial cellulose-pectin-xyloglucan composite with 0.3 % (w/v) xyloglucan, previously shown to have the highest number of Salmonella cells attached to it, had significantly thicker cellulose fibrils compared to other composites. Scanning electron microscopy images also showed that the bacterial cellulose and bacterial cellulose-xyloglucan composites were more porous when compared to the other composites containing pectin. Our study found that the attachment of Salmonella cells to cut plant cell walls was not mediated by

  15. Type III Interferon-Mediated Signaling Is Critical for Controlling Live Attenuated Yellow Fever Virus Infection In Vivo.

    Science.gov (United States)

    Douam, Florian; Soto Albrecht, Yentli E; Hrebikova, Gabriela; Sadimin, Evita; Davidson, Christian; Kotenko, Sergei V; Ploss, Alexander

    2017-08-15

    role of type III interferon (IFN)-mediated signaling, a host immune defense mechanism, in controlling YFV-17D infection and attenuation in different mouse models. We uncovered a critical role of type III IFN-mediated signaling in preserving the integrity of the blood-brain barrier and preventing viral brain invasion. Type III IFN also played a major role in regulating the induction of a potent but balanced immune response that prevented viral evasion of the host immune system. An improved understanding of the complex mechanisms regulating YFV-17D attenuation will provide insights into the key virus-host interactions that regulate host immune responses and infection outcomes as well as open novel avenues for the development of innovative vaccine strategies. Copyright © 2017 Douam et al.

  16. Same species, different diseases: how and why typhoidal and non-typhoidal Salmonella enterica serovars differ

    Directory of Open Access Journals (Sweden)

    Ohad eGal-Mor

    2014-08-01

    Full Text Available Human infections by the bacterial pathogen Salmonella enterica represent major disease burdens worldwide. This highly ubiquitous species consists of more than 2600 different serovars that can be divided into typhoidal and non-typhoidal Salmonella (NTS serovars. Despite their genetic similarity, these two groups elicit very different diseases and distinct immune responses in humans. Comparative analyses of the genomes of multiple Salmonella serovars have begun to explain the basis of the variation in disease manifestations. Recent advances in modeling both enteric fever and intestinal gastroenteritis in mice will facilitate investigation into both the bacterial- and host-mediated mechanisms involved in salmonelloses. Understanding the genetic and molecular mechanisms responsible for differences in disease outcome will augment our understanding of Salmonella pathogenesis, host immunity, and the molecular basis of host specificity. This review outlines the differences in epidemiology, clinical manifestations, and the human immune response to typhoidal and NTS infections and summarizes the current thinking on why these differences might exist.

  17. 78 FR 42526 - Salmonella

    Science.gov (United States)

    2013-07-16

    ...] Salmonella Contamination of Dry Dog Food; Withdrawal of Compliance Policy Guide AGENCY: Food and Drug... the withdrawal of the compliance policy guide (CPG) entitled ``Sec. 690.700 Salmonella Contamination... entitled ``Sec. 690.700 Salmonella Contamination of Dry Dog Food (CPG 690.700)'' on October 1, 1980. CPG...

  18. Salmonella biofilms

    NARCIS (Netherlands)

    Castelijn, G.A.A.

    2013-01-01

    Biofilm formation by Salmonellaspp. is a problem in the food industry, since biofilms may act as a persistent source of product contamination. Therefore the aim of this study was to obtain more insight in the processes involved and the factors contributing to Salmonellabiofilm

  19. Genomics of Salmonella Species

    Science.gov (United States)

    Canals, Rocio; McClelland, Michael; Santiviago, Carlos A.; Andrews-Polymenis, Helene

    Progress in the study of Salmonella survival, colonization, and virulence has increased rapidly with the advent of complete genome sequencing and higher capacity assays for transcriptomic and proteomic analysis. Although many of these techniques have yet to be used to directly assay Salmonella growth on foods, these assays are currently in use to determine Salmonella factors necessary for growth in animal models including livestock animals and in in vitro conditions that mimic many different environments. As sequencing of the Salmonella genome and microarray analysis have revolutionized genomics and transcriptomics of salmonellae over the last decade, so are new high-throughput sequencing technologies currently accelerating the pace of our studies and allowing us to approach complex problems that were not previously experimentally tractable.

  20. Prevalence of Salmonella in Australian reptiles.

    Science.gov (United States)

    Scheelings, T Franciscus; Lightfoot, Dianne; Holz, Peter

    2011-01-01

    From January 2007 until June 2008, 504 reptiles of four families and 57 species were examined for Salmonella by using cloacal or intestinal swabs. Salmonella was identified in 139 (28%) of the 504 animals tested. Of the 504 reptiles examined, 210 were captive and 294 were wild. Ninety-eight (47%) of the captive reptiles were shedding Salmonella at the time of sampling. In contrast, only 41 (14%) of the wild reptiles were shedding Salmonella. The higher prevalence of Salmonella in captive reptiles was statistically significant (Preptiles in Australia are not natural carriers of Salmonella and that diet and captivity may influence Salmonella excretion in other species.

  1. lac repressor is an antivirulence factor of Salmonella enterica: its role in the evolution of virulence in Salmonella.

    Directory of Open Access Journals (Sweden)

    Sandeepa M Eswarappa

    Full Text Available The genus Salmonella includes many pathogens of great medical and veterinary importance. Bacteria belonging to this genus are very closely related to those belonging to the genus Escherichia. lacZYA operon and lacI are present in Escherichia coli, but not in Salmonella enterica. It has been proposed that Salmonella has lost lacZYA operon and lacI during evolution. In this study, we have investigated the physiological and evolutionary significance of the absence of lacI in Salmonella enterica. Using murine model of typhoid fever, we show that the expression of LacI causes a remarkable reduction in the virulence of Salmonella enterica. LacI also suppresses the ability of Salmonella enterica to proliferate inside murine macrophages. Microarray analysis revealed that LacI interferes with the expression of virulence genes of Salmonella pathogenicity island 2. This effect was confirmed by RT-PCR and Western blot analysis. Interestingly, we found that SBG0326 of Salmonella bongori is homologous to lacI of Escherichia coli. Salmonella bongori is the only other species of the genus Salmonella and it lacks the virulence genes of Salmonella pathogenicity island 2. Overall, our results demonstrate that LacI is an antivirulence factor of Salmonella enterica and suggest that absence of lacI has facilitated the acquisition of virulence genes of Salmonella pathogenicity island 2 in Salmonella enterica making it a successful systemic pathogen.

  2. A downy mildew effector attenuates salicylic acid-triggered immunity in Arabidopsis by interacting with the host mediator complex.

    Directory of Open Access Journals (Sweden)

    Marie-Cécile Caillaud

    2013-12-01

    Full Text Available Plants are continually exposed to pathogen attack but usually remain healthy because they can activate defences upon perception of microbes. However, pathogens have evolved to overcome plant immunity by delivering effectors into the plant cell to attenuate defence, resulting in disease. Recent studies suggest that some effectors may manipulate host transcription, but the specific mechanisms by which such effectors promote susceptibility remain unclear. We study the oomycete downy mildew pathogen of Arabidopsis, Hyaloperonospora arabidopsidis (Hpa, and show here that the nuclear-localized effector HaRxL44 interacts with Mediator subunit 19a (MED19a, resulting in the degradation of MED19a in a proteasome-dependent manner. The Mediator complex of ∼25 proteins is broadly conserved in eukaryotes and mediates the interaction between transcriptional regulators and RNA polymerase II. We found MED19a to be a positive regulator of immunity against Hpa. Expression profiling experiments reveal transcriptional changes resembling jasmonic acid/ethylene (JA/ET signalling in the presence of HaRxL44, and also 3 d after infection with Hpa. Elevated JA/ET signalling is associated with a decrease in salicylic acid (SA-triggered immunity (SATI in Arabidopsis plants expressing HaRxL44 and in med19a loss-of-function mutants, whereas SATI is elevated in plants overexpressing MED19a. Using a PR1::GUS reporter, we discovered that Hpa suppresses PR1 expression specifically in cells containing haustoria, into which RxLR effectors are delivered, but not in nonhaustoriated adjacent cells, which show high PR1::GUS expression levels. Thus, HaRxL44 interferes with Mediator function by degrading MED19, shifting the balance of defence transcription from SA-responsive defence to JA/ET-signalling, and enhancing susceptibility to biotrophs by attenuating SA-dependent gene expression.

  3. Oral immunisation of laying hens with the live vaccine strains of TAD Salmonella vac E and TAD Salmonella vac T reduces internal egg contamination with Salmonella Enteritidis.

    Science.gov (United States)

    Gantois, Inne; Ducatelle, Richard; Timbermont, Leen; Boyen, Filip; Bohez, Lotte; Haesebrouck, Freddy; Pasmans, Frank; van Immerseel, Filip

    2006-09-11

    Eggs are a major source of human infections with Salmonella. Therefore controlling egg contamination in laying hen flocks is one of the main targets for control programmes. A study was carried out to assess the effect of oral vaccination with TAD Salmonella vac E, TAD Salmonella vac T and with both vaccines TAD Salmonella vac E and TAD Salmonella vac T, on colonization of the reproductive tract and internal egg contamination of laying hens with Salmonella Enteritidis. Three groups of 30 laying hens were vaccinated at 1 day, 6 weeks and 16 weeks of age with either one of the vaccine strains, or a combination of both vaccine strains, while a fourth group was left unvaccinated. At 24 weeks of age, the birds were intravenously challenged with 0.5 ml containing 5 x 10(7)cfu Salmonella Enteritidis PT4 S1400/94. The number of oviducts from which Salmonella was isolated, was significantly lower in the vaccinated than in the non-vaccinated hens at 3 weeks post-challenge. Significantly less egg contents were Salmonella positive in the birds vaccinated with TAD Salmonella vac E or TAD Salmonella vac T (12/105 batches of eggs in both groups) than in the unvaccinated birds (28/105 batches of eggs). Internal egg contamination in the hens vaccinated with both TAD Salmonella vac E and TAD Salmonella vac T was even more reduced, as over the whole experiment, only one batch of eggs was positive. In conclusion, these data indicate that vaccination of laying hens with these live vaccines could be considered as a valuable tool in controlling internal egg contamination.

  4. Mechanism of estrogen-mediated attenuation of hepatic injury following trauma-hemorrhage: Akt-dependent HO-1 up-regulation.

    Science.gov (United States)

    Hsu, Jun-Te; Kan, Wen-Hong; Hsieh, Chi-Hsun; Choudhry, Mashkoor A; Schwacha, Martin G; Bland, Kirby I; Chaudry, Irshad H

    2007-10-01

    Protein kinase B (Akt) is known to be involved in proinflammatory and chemotactic events in response to injury. Akt activation also leads to the induction of heme oxygenase (HO)-1. Up-regulation of HO-1 mediates potent, anti-inflammatory effects and attenuates organ injury. Although studies have shown that 17beta-estradiol (E2) prevents organ damage following trauma-hemorrhage, it remains unknown whether Akt/HO-1 plays any role in E2-mediated attenuation of hepatic injury following trauma-hemorrhage. To study this, male rats underwent trauma-hemorrhage (mean blood pressure, approximately 40 mmHg for 90 min), followed by fluid resuscitation. At the onset of resuscitation, rats were treated with vehicle, E2 (1 mg/kg body weight), E2 plus the PI-3K inhibitor (Wortmannin), or the estrogen receptor (ER) antagonist (ICI 182,780). At 2 h after sham operation or trauma-hemorrhage, plasma alpha-GST and hepatic tissue myeloperoxidase (MPO) activity, IL-6, TNF-alpha, ICAM-1, cytokine-induced neutrophil chemoattractant-1, and MIP-2 levels were measured. Hepatic Akt and HO-1 protein levels were also determined. Trauma-hemorrhage increased hepatic injury markers (alpha-GST and MPO activity), cytokines, ICAM-1, and chemokine levels. These parameters were markedly improved in the E2-treated rats following trauma-hemorrhage. E2 treatment also increased hepatic Akt activation and HO-1 expression compared with vehicle-treated, trauma-hemorrhage rats, which were abolished by coadministration of Wortmannin or ICI 182,780. These results suggest that the salutary effects of E2 on hepatic injury following trauma-hemorrhage are in part mediated via an ER-related, Akt-dependent up-regulation of HO-1.

  5. Supercritical CO2 extraction of Schinus molle L with co-solvents: mathematical modeling and antimicrobial applications

    Directory of Open Access Journals (Sweden)

    Rodrigo Scopel

    2013-06-01

    Full Text Available This work investigates the antimicrobial activity of the Schinus molle L. leaves extracts obtained under supercritical conditions using carbon dioxide and co-solvents. Antimicrobial qualitative evaluation was carried out through the bioautography technique and the microorganisms studied were Staphylococcus aureus, Pseudomonas aeruginosas, Escherichia coli, Micrococcus luteus, and Salmonella choleraesuis. The supercritical fluid extraction was carried out in a pilot scale equipment using carbon dioxide modified by the addition of co-solvents, such as ethanol and water at 150 bar and 333 K. A mathematical modeling of the process was also performed.

  6. Analysis of interactions of Salmonella type three secretion mutants with 3-D intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Andrea L Radtke

    Full Text Available The prevailing paradigm of Salmonella enteropathogenesis based on monolayers asserts that Salmonella pathogenicity island-1 Type Three Secretion System (SPI-1 T3SS is required for bacterial invasion into intestinal epithelium. However, little is known about the role of SPI-1 in mediating gastrointestinal disease in humans. Recently, SPI-1 deficient nontyphoidal Salmonella strains were isolated from infected humans and animals, indicating that SPI-1 is not required to cause enteropathogenesis and demonstrating the need for more in vivo-like models. Here, we utilized a previously characterized 3-D organotypic model of human intestinal epithelium to elucidate the role of all characterized Salmonella enterica T3SSs. Similar to in vivo reports, the Salmonella SPI-1 T3SS was not required to invade 3-D intestinal cells. Additionally, Salmonella strains carrying single (SPI-1 or SPI-2, double (SPI-1/2 and complete T3SS knockout (SPI-1/SPI-2: flhDC also invaded 3-D intestinal cells to wildtype levels. Invasion of wildtype and TTSS mutants was a Salmonella active process, whereas non-invasive bacterial strains, bacterial size beads, and heat-killed Salmonella did not invade 3-D cells. Wildtype and T3SS mutants did not preferentially target different cell types identified within the 3-D intestinal aggregates, including M-cells/M-like cells, enterocytes, or Paneth cells. Moreover, each T3SS was necessary for substantial intracellular bacterial replication within 3-D cells. Collectively, these results indicate that T3SSs are dispensable for Salmonella invasion into highly differentiated 3-D models of human intestinal epithelial cells, but are required for intracellular bacterial growth, paralleling in vivo infection observations and demonstrating the utility of these models in predicting in vivo-like pathogenic mechanisms.

  7. Safety and immunogenicity of Salmonella typhimurium expressing C-terminal truncated human IL-2 in a murine model

    Directory of Open Access Journals (Sweden)

    Brent Sorenson

    2010-03-01

    Full Text Available Brent Sorenson, Kaysie Banton, Lance Augustin, Sean Barnett, Karen McCulloch, Joshua Dorn, Natalie Frykman, Arnold Leonard, Daniel SaltzmanDepartment of Surgery, University of Minnesota Medical School, Minneapolis, MN, USAAbstract: Salmonella enterica serovar Typhimurium preferentially colonizes tumors in vivo and has proven to be an effective biologic vector. The attenuated S. enterica Typhimurium strain χ4550 was engineered to express truncated human interleukin-2 and renamed SalpIL2. Previously, we observed that a single oral administration of SalpIL2 reduced tumor number and volume, while significantly increasing local and systemic natural killer (NK cell populations in an experimental metastasis model. Here we report that in nontumor-bearing mice, a single oral dose of SalpIL2 resulted in increased splenic cytotoxic T and NK cell populations that returned to control levels by 4 weeks post oral administration. Though SalpIL2 was detected in mouse tissues for up to 10 weeks, no prolonged alterations in peripheral blood serum chemistry or complete blood cell counts were observed. Similarly, comparative histopathological analysis of tissues revealed no significant increase in pyogranulomas in SalpIL2-treated animals with respect to saline controls. In Rag-1 knockout mice, which have severely impaired B and T cell function, SalpIL2 reduced growth of hepatic metastases. Furthermore, SalpIL2 altered expression of several proinflammatory cytokines and chemokines in the serum of mice with pulmonary osteosarcoma metastases. These data further suggest that SalpIL2 is avirulent and induces a cell-mediated antitumor response.Keywords: Salmonella Typhimurium, natural killer cells, interleukin-2

  8. Broad-range (pan) Salmonella and Salmonella serotype typhi-specific real-time PCR assays: potential tools for the clinical microbiologist.

    Science.gov (United States)

    Farrell, John J; Doyle, Laura J; Addison, Rachel M; Reller, L Barth; Hall, Geraldine S; Procop, Gary W

    2005-03-01

    We describe broad-range salmonellae (ie, Salmonella) and Salmonella serotype Typhi-specific LightCycler (Roche Diagnostics, Indianapolis, IN) real-time polymerase chain reaction assays. We validated these with a battery of 280 bacteria, 108 of which were salmonellae representing 20 serotypes. In addition, 298 isolates from 170 clinical specimens that were suspected to possibly represent Salmonella were tested with the pan- Salmonella assay. Finally, the pan-Salmonella assay also was used to test DNA extracts from 101 archived, frozen stool specimens, 55 of which were culture-positive for salmonellae. Both assays were 100% sensitive and specific when cultured isolates of the battery were tested. The pan- Salmonella assay also characterized correctly all salmonellae on the primary isolation agar and was 96% sensitive (53/55) and 96% specific (49/51) when nucleic acid extracts from direct stool specimens were tested. These assays represent potential tools the clinical microbiologist could use to screen suspect isolates or stool specimens for Salmonella.

  9. N-Acetylcysteine protects against trichloroethene-mediated autoimmunity by attenuating oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Gangduo; Wang, Jianling; Ma, Huaxian; Ansari, G.A.S.; Khan, M. Firoze, E-mail: mfkhan@utmb.edu

    2013-11-15

    Exposure to trichloroethene (TCE), a ubiquitous environmental contaminant, is known to induce autoimmunity both in humans and animal models. However, mechanisms underlying TCE-mediated autoimmunity remain largely unknown. Previous studies from our laboratory in MRL +/+ mice suggest that oxidative stress may contribute to TCE-induced autoimmune response. The current study was undertaken to further assess the role of oxidative stress in TCE-induced autoimmunity by supplementing with an antioxidant N-acetylcysteine (NAC). Groups of female MRL +/+ mice were given TCE, NAC or TCE + NAC for 6 weeks (TCE, 10 mmol/kg, i.p., every 4th day; NAC, 250 mg/kg/day through drinking water). TCE exposure led to significant increases in serum levels of anti-nuclear, anti-dsDNA and anti-Sm antibodies. TCE exposure also led to significant induction of anti-malondiadelhyde (MDA)- and anti-hydroxynonenal (HNE)-protein adduct antibodies which were associated with increased ANA in the sera along with increased MDA-/HNE-protein adducts in the livers and kidneys, and increases in protein oxidation (carbonylation) in the sera, livers and kidneys, suggesting an overall increase in oxidative stress. Moreover, TCE exposure also resulted in increased release of IL-17 from splenocytes and increases in IL-17 mRNA expression. Remarkably, NAC supplementation attenuated not only the TCE-induced oxidative stress, IL-17 release and mRNA expression, but also the markers of autoimmunity, as evident from decreased levels of ANA, anti-dsDNA and anti-Sm antibodies in the sera. These results provide further support to a role of oxidative stress in TCE-induced autoimmune response. Attenuation of TCE-induced autoimmunity in mice by NAC provides an approach for preventive and/or therapeutic strategies. - Highlights: • TCE led to increased autoantibodies, supporting its potential to induce autoimmunity. • TCE exposure led to increases in lipid perioxidation and protein carbonyls. • TCE exposure resulted in

  10. N-Acetylcysteine protects against trichloroethene-mediated autoimmunity by attenuating oxidative stress

    International Nuclear Information System (INIS)

    Wang, Gangduo; Wang, Jianling; Ma, Huaxian; Ansari, G.A.S.; Khan, M. Firoze

    2013-01-01

    Exposure to trichloroethene (TCE), a ubiquitous environmental contaminant, is known to induce autoimmunity both in humans and animal models. However, mechanisms underlying TCE-mediated autoimmunity remain largely unknown. Previous studies from our laboratory in MRL +/+ mice suggest that oxidative stress may contribute to TCE-induced autoimmune response. The current study was undertaken to further assess the role of oxidative stress in TCE-induced autoimmunity by supplementing with an antioxidant N-acetylcysteine (NAC). Groups of female MRL +/+ mice were given TCE, NAC or TCE + NAC for 6 weeks (TCE, 10 mmol/kg, i.p., every 4th day; NAC, 250 mg/kg/day through drinking water). TCE exposure led to significant increases in serum levels of anti-nuclear, anti-dsDNA and anti-Sm antibodies. TCE exposure also led to significant induction of anti-malondiadelhyde (MDA)- and anti-hydroxynonenal (HNE)-protein adduct antibodies which were associated with increased ANA in the sera along with increased MDA-/HNE-protein adducts in the livers and kidneys, and increases in protein oxidation (carbonylation) in the sera, livers and kidneys, suggesting an overall increase in oxidative stress. Moreover, TCE exposure also resulted in increased release of IL-17 from splenocytes and increases in IL-17 mRNA expression. Remarkably, NAC supplementation attenuated not only the TCE-induced oxidative stress, IL-17 release and mRNA expression, but also the markers of autoimmunity, as evident from decreased levels of ANA, anti-dsDNA and anti-Sm antibodies in the sera. These results provide further support to a role of oxidative stress in TCE-induced autoimmune response. Attenuation of TCE-induced autoimmunity in mice by NAC provides an approach for preventive and/or therapeutic strategies. - Highlights: • TCE led to increased autoantibodies, supporting its potential to induce autoimmunity. • TCE exposure led to increases in lipid perioxidation and protein carbonyls. • TCE exposure resulted in

  11. Molecular epidemiology of fluoroquinolone resistant Salmonella in Africa: A systematic review and meta-analysis.

    Science.gov (United States)

    Tadesse, Getachew; Tessema, Tesfaye S; Beyene, Getenet; Aseffa, Abraham

    2018-01-01

    Wide-ranging evidence on the occurrence of fluoroquinolone (FQ) resistance genetic determinants in African Salmonella strains is not available. The main objectives of this study were to assess the heterogeneity, estimate pooled proportions and describe the preponderance of FQ-resistance determinants in typhoidal and non-typhoidal Salmonella (NTS) isolates of Africa. Genetic and phenotypic data on 6103 Salmonella isolates were considered. Meta- and frequency analyses were performed depending on the number of studies by category, number of isolates and risks of bias. A random effects model was used to assess heterogeneity and estimate pooled proportions. Relative and cumulative frequencies were calculated to describe the overall preponderance of FQ-resistance determinants in quinolone resistant isolates. The pooled proportion of gyrA mutants (Salmonella enterica serovar Typhi, Salmonella enterica serovar Typhimurium, and Salmonella enterica serovar Enteritidis) was estimated at 5.7% (95% Confidence interval (CI) = 2.6, 9.8; Tau squared (T2) = 0.1105), and was higher in S. Typhi than in S. Typhimurium (odds ratio (OR) = 3.3, 95%CI = 2, 5.7). The proportions of each of gyrB and parC mutants, and strains with Plasmid Mediated Quinolone Resistance genes (qnrA, qnrB and qnrS) were low (≤ 0.3%). Overall, 23 mutant serotypes were identified, and most strains had mutations at codons encoding Ser83 and Asp87 of gyrA (82%, 95%CI = 78, 86). Mutations at gyrA appear to account for ciprofloxacin non-susceptibility in most clinical Salmonella strains in Africa. The estimates could be harnessed to develop a mismatch-amplification mutation-assay for the detection of FQ-resistant strains in Africa.

  12. Acidic pH sensing in the bacterial cytoplasm is required for Salmonella virulence.

    Science.gov (United States)

    Choi, Jeongjoon; Groisman, Eduardo A

    2016-09-01

    pH regulates gene expression, biochemical activities and cellular behaviors. A mildly acidic pH activates the master virulence regulatory system PhoP/PhoQ in the facultative intracellular pathogen Salmonella enterica serovar Typhimurium. The sensor PhoQ harbors an extracytoplasmic domain implicated in signal sensing, and a cytoplasmic domain controlling activation of the regulator PhoP. We now report that, surprisingly, a decrease in Salmonella's own cytoplasmic pH induces transcription of PhoP-activated genes even when the extracytoplasmic pH remains neutral. Amino acid substitutions in PhoQ's cytoplasmic domain hindered activation by acidic pH and attenuated virulence in mice, but did not abolish activation by low Mg(2+) or the antimicrobial peptide C18G. Conversely, removal of PhoQ's extracytoplasmic domains prevented the response to the latter PhoQ-activating signals but not to acidic pH. PhoP-dependent genes were minimally induced by acidic pH in the non-pathogenic species Salmonella bongori but were activated by low Mg(2+) and C18G as in pathogenic S. enterica. Our findings indicate that the sensor PhoQ enables S. enterica to respond to both host- and bacterial-derived signals that alter its cytoplasmic pH. © 2016 John Wiley & Sons Ltd.

  13. Non-Saccharomyces yeasts protect against epithelial cell barrier disruption induced by Salmonella enterica subsp. enterica serovar Typhimurium.

    Science.gov (United States)

    Smith, I M; Baker, A; Arneborg, N; Jespersen, L

    2015-11-01

    The human gastrointestinal epithelium makes up the largest barrier separating the body from the external environment. Whereas invasive pathogens cause epithelial barrier disruption, probiotic micro-organisms modulate tight junction regulation and improve epithelial barrier function. In addition, probiotic strains may be able to reduce epithelial barrier disruption caused by pathogenic species. The aim of this study was to explore non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Benchmarking against established probiotic strains, we evaluated the ability of four nonpathogenic yeast species to modulate transepithelial electrical resistance (TER) across a monolayer of differentiated human colonocytes (Caco-2 cells). Further, we assessed yeast modulation of a Salmonella Typhimurium-induced epithelial cell barrier function insult. Our findings demonstrate distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function. While the established probiotic yeast Saccharomyces boulardii increased TER across a Caco-2 monolayer by 30%, Kluyveromyces marxianus exhibited significantly stronger properties of TER enhancement (50% TER increase). In addition, our data demonstrate significant yeast-mediated modulation of Salmonella-induced epithelial cell barrier disruption and identify K. marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. This study demonstrates distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Further, our data demonstrate significant yeast-mediated modulation of Salmonella Typhimurium-induced epithelial cell barrier disruption and identify Kluyveromyces marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. This study is the first to demonstrate significant non-Saccharomyces yeast-mediated

  14. Interaction mediated by the putative tip regions of MdsA and MdsC in the formation of a Salmonella-specific tripartite efflux pump.

    Directory of Open Access Journals (Sweden)

    Saemee Song

    Full Text Available To survive in the presence of a wide range of toxic compounds, gram-negative bacteria expel such compounds via tripartite efflux pumps that span both the inner and outer membranes. The Salmonella-specific MdsAB pump consists of MdsB, a resistance-nodulation-division (RND-type inner membrane transporter (IMT that requires the membrane fusion protein (MFP MdsA, and an outer membrane protein (OMP; MdsC or TolC to form a tripartite efflux complex. In this study, we investigated the role of the putative tip regions of MdsA and its OMPs, MdsC and TolC, in the formation of a functional MdsAB-mediated efflux pump. Comparative analysis indicated that although sequence homologies of MdsA and MdsC with other MFPs and OMPs, respectively, are extremely low, key residues in the putative tip regions of these proteins are well conserved. Mutagenesis studies on these conserved sites demonstrated their importance for the physical and functional interactions required to form an MdsAB-mediated pump. Our studies suggest that, despite differences in the primary amino acid sequences and functions of various OMPs and MFPs, interactions mediated by the conserved tip regions of OMP and MFP are required for the formation of functional tripartite efflux pumps in gram-negative bacteria.

  15. Plasmid mediated quinolone resistance in Enterobacteriaceae

    NARCIS (Netherlands)

    Veldman, K.T.; LS Klinisch Onderzoek Wagenaar

    2014-01-01

    This thesis describes the occurrence of Plasmid Mediated Quinolone Resistance (PMQR) in Salmonella and E. coli from The Netherlands and other European countries. Furthermore, the genetic background of these genes was characterized. Fluoroquinolones are widely used antibiotics in both human and

  16. Induction of feline immunodeficiency virus specific antibodies in cats with an attenuated Salmonella strain expressing the Gag protein.

    NARCIS (Netherlands)

    E.J. Tijhaar (Edwin); C.H.J. Siebelink (Kees); J.A. Karlas (Jos); M.C. Burger; F.R. Mooi (Frits); A.D.M.E. Osterhaus (Albert)

    1997-01-01

    textabstractSalmonella typhimurium aroA strains (SL3261), expressing high levels of the Gag protein of feline immunodeficiency virus (FIV) fused with maltose binding protein (SL3261-MFG), were constructed using an invertible promoter system that allows the stable expression of heterologous antigens

  17. Recent Trends in Salmonella Outbreaks and Emerging Technology for Biocontrol of Salmonella Using Phages in Foods: A Review.

    Science.gov (United States)

    Oh, Jun-Hyun; Park, Mi-Kyung

    2017-12-28

    Salmonella is one of the principal causes of foodborne outbreaks. As traditional control methods have shown less efficacy against emerging Salmonella serotypes or antimicrobialresistant Salmonella , new approaches have been attempted. The use of lytic phages for the biocontrol of Salmonella in the food industry has become an attractive method owing to the many advantages offered by the use of phages as biocontrol agents. Phages are natural alternatives to traditional antimicrobial agents; they have proven effective in the control of bacterial pathogens in the food industry, which has led to the development of different phage products. The treatment with specific phages in the food industry can prevent the decay of products and the spread of bacterial diseases, and ultimately promotes safe environments for animal and plant food production, processing, and handling. After an extensive investigation of the current literature, this review focuses predominantly on the efficacy of phages for the successful control of Salmonella spp. in foods. This review also addresses the current knowledge on the pathogenic characteristics of Salmonella , the prevalence of emerging Salmonella outbreaks, the isolation and characterization of Salmonella -specific phages, the effectiveness of Salmonella -specific phages as biocontrol agents, and the prospective use of Salmonella -specific phages in the food industry.

  18. Intraspecies Competition for Niches in the Distal Gut Dictate Transmission during Persistent Salmonella Infection

    Science.gov (United States)

    Lam, Lilian H.; Monack, Denise M.

    2014-01-01

    In order to be transmitted, a pathogen must first successfully colonize and multiply within a host. Ecological principles can be applied to study host-pathogen interactions to predict transmission dynamics. Little is known about the population biology of Salmonella during persistent infection. To define Salmonella enterica serovar Typhimurium population structure in this context, 129SvJ mice were oral gavaged with a mixture of eight wild-type isogenic tagged Salmonella (WITS) strains. Distinct subpopulations arose within intestinal and systemic tissues after 35 days, and clonal expansion of the cecal and colonic subpopulation was responsible for increases in Salmonella fecal shedding. A co-infection system utilizing differentially marked isogenic strains was developed in which each mouse received one strain orally and the other systemically by intraperitoneal (IP) injection. Co-infections demonstrated that the intestinal subpopulation exerted intraspecies priority effects by excluding systemic S. Typhimurium from colonizing an extracellular niche within the cecum and colon. Importantly, the systemic strain was excluded from these distal gut sites and was not transmitted to naïve hosts. In addition, S. Typhimurium required hydrogenase, an enzyme that mediates acquisition of hydrogen from the gut microbiota, during the first week of infection to exert priority effects in the gut. Thus, early inhibitory priority effects are facilitated by the acquisition of nutrients, which allow S. Typhimurium to successfully compete for a nutritional niche in the distal gut. We also show that intraspecies colonization resistance is maintained by Salmonella Pathogenicity Islands SPI1 and SPI2 during persistent distal gut infection. Thus, important virulence effectors not only modulate interactions with host cells, but are crucial for Salmonella colonization of an extracellular intestinal niche and thereby also shape intraspecies dynamics. We conclude that priority effects and

  19. Isolation and Evaluation Virulence Factors of Salmonella typhimurium and Salmonella enteritidis in Milk and Dairy Products

    Directory of Open Access Journals (Sweden)

    Shima Shaigan nia

    2014-06-01

    Conclusions: To our best knowledge the present study is the first prevalence report of Salmonella spp., Salmonella enteritidis and Salmonella typhimurium in raw sheep and goat samples in Iran. Consumption of pasteurized milk and dairy products can reduce the risk of salmonellosis.

  20. PREVALENCE OF SALMONELLA IN CAPTIVE REPTILES FROM CROATIA.

    Science.gov (United States)

    Lukac, Maja; Pedersen, Karl; Prukner-Radovcic, Estella

    2015-06-01

    Salmonellosis transmitted by pet reptiles is an increasing public health issue worldwide. The aim of this study was to investigate the prevalence of Salmonella strains from captive reptiles in Croatia. From November 2009 to November 2011 a total of 292 skin, pharyngeal, cloacal, and fecal samples from 200 apparently healthy reptiles were tested for Salmonella excretions by bacteriologic culture and serotyping. These 200 individual reptiles included 31 lizards, 79 chelonians, and 90 snakes belonging to private owners or housed at the Zagreb Zoo, Croatia. Salmonella was detected in a total of 13% of the animals, among them 48.4% lizards, 8.9% snakes, and 3.8% turtles. Representatives of five of the six Salmonella enterica subspecies were identified with the following proportions in the total number of isolates: Salmonella enterica enterica 34.6%, Salmonella enterica houtenae 23.1%, Salmonella enterica arizonae 23.1%, Salmonella enterica diarizonae 15.4%, and Salmonella enterica salamae 3.8%. The 14 different serovars isolated included several rarely occurring serovars such as Salmonella Apapa, Salmonella Halle, Salmonella Kisarawe, and Salmonella Potengi. These findings confirm that the prevalence of Salmonella is considerable in captive reptiles in Croatia, indicating that these animals may harbor serovars not commonly seen in veterinary or human microbiologic practice. This should be addressed in the prevention and diagnostics of human reptile-transmitted infections.

  1. Endogenous n-3 polyunsaturated fatty acids attenuate T cell-mediated hepatitis via autophagy activation

    Directory of Open Access Journals (Sweden)

    Yanli Li

    2016-09-01

    Full Text Available Omega-3 polyunsaturated fatty acids (n-3 PUFAs exert anti-inflammatory effects in several liver disorders, including cirrhosis, acute liver failure, and fatty liver disease. To date, little is known about their role in immune-mediated liver diseases. In this study, we used fat-1 transgenic mice rich in endogenous n-3 PUFAs to examine the role of n-3 PUFAs in immune-mediated liver injury. Concanavalin A (Con A was administered intravenously to wild-type (WT and fat-1 transgenic mice to induce T cell-mediated hepatitis. Reduced liver damage was shown in Con A-administrated fat-1 transgenic mice, as evidenced by decreased mortality, attenuated hepatic necrosis, lessened serum alanine aminotransferase (ALT activity, and inhibited production of pro-inflammatory cytokines (e.g. TNF-α, IL-6, IL-17A and IFN-γ. In vivo and in vitro studies demonstrated that n-3 PUFAs significantly inhibited the activation of hepatic T cells and the differentiation of Th1 cells after Con A challenge. Further studies showed that n-3 PUFAs markedly increased autophagy level in Con A-treated fat-1 T cells compared with the WT counterparts. Blocking hepatic autophagy activity with chloroquine diminished the differences in T cell activation and liver injury between Con A-injected WT and fat-1 transgenic mice. We conclude that n-3 PUFAs limit Con A-induced hepatitis via an autophagy-dependent mechanism, and could be exploited as a new therapeutic approach for autoimmune hepatitis.

  2. Oral immunization using HgbA in a recombinant chancroid vaccine delivered by attenuated Salmonella typhimurium SL3261 in the temperature-dependent rabbit model.

    Science.gov (United States)

    Breau, Cathy; Cameron, D William; Desjardins, Marc; Lee, B Craig

    2012-01-31

    Chancroid, a sexually transmitted genital ulcer disease caused by the Gram-negative bacterium Haemophilus ducreyi, facilitates the acquisition and transmission of HIV. An effective vaccine against chancroid has not been developed. In this preliminary study, the gene encoding the H. ducreyi outer membrane hemoglobin receptor HgbA was cloned into the plasmid pTETnir15. The recombinant construct was introduced into the attenuated Salmonella typhimurium SL3261 strain and stable expression was induced in vitro under anaerobic conditions. The vaccine strain was delivered into the temperature-dependent rabbit model of chancroid by intragastric immunization as a single dose, or as three doses administered at two-weekly intervals. No specific antibody to HgbA was elicited after either dose schedule. Although the plasmid vector survived in vivo passage for up to 15 days following single oral challenge, HgbA expression was restricted to plasmid isolates recovered one day after immunization. Rabbits inoculated with the 3-dose booster regimen achieved no protective immunity from homologous challenge. These results emphasize that refinements in plasmid design to enhance a durable heterologous protein expression are necessary for the development of a live oral vaccine against chancroid. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. 9 CFR 113.120 - Salmonella Typhimurium Bacterin.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Typhimurium Bacterin. 113... REQUIREMENTS Inactivated Bacterial Products § 113.120 Salmonella Typhimurium Bacterin. Salmonella Typhimurium Bacterin shall be prepared from a culture of Salmonella typhimurium which has been inactivated and is...

  4. Polyamines are essential for virulence in Salmonella enterica serovar Gallinarum despite evolutionary decay of polyamine biosynthesis genes.

    Science.gov (United States)

    Schroll, Casper; Christensen, Jens P; Christensen, Henrik; Pors, Susanne E; Thorndahl, Lotte; Jensen, Peter R; Olsen, John E; Jelsbak, Lotte

    2014-05-14

    Serovars of Salmonella enterica exhibit different host-specificities where some have broad host-ranges and others, like S. Gallinarum and S. Typhi, are host-specific for poultry and humans, respectively. With the recent availability of whole genome sequences it has been reported that host-specificity coincides with accumulation of pseudogenes, indicating adaptation of host-restricted serovars to their narrow niches. Polyamines are small cationic amines and in Salmonella they can be synthesized through two alternative pathways directly from l-ornithine to putrescine and from l-arginine via agmatine to putrescine. The first pathway is not active in S. Gallinarum and S. Typhi, and this prompted us to investigate the importance of polyamines for virulence in S. Gallinarum. Bioinformatic analysis of all sequenced genomes of Salmonella revealed that pseudogene formation of the speC gene was exclusive for S. Typhi and S. Gallinarum and happened through independent events. The remaining polyamine biosynthesis pathway was found to be essential for oral infection with S. Gallinarum since single and double mutants in speB and speE, encoding the pathways from agmatine to putrescine and from putrescine to spermidine, were attenuated. In contrast, speB was dispensable after intraperitoneal challenge, suggesting that putrescine was less important for the systemic phase of the disease. In support of this hypothesis, a ΔspeE;ΔpotCD mutant, unable to synthesize and import spermidine, but with retained ability to import and synthesize putrescine, was attenuated after intraperitoneal infection. We therefore conclude that polyamines are essential for virulence of S. Gallinarum. Furthermore, our results point to distinct roles for putrescine and spermidine during systemic infection. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Salmonella spp. in raw broiler parts: occurrence, antimicrobial resistance profile and phage typing of the Salmonella Enteritidis isolates Salmonella spp. em cortes de frango: ocorrência, resistência antimicrobiana e fagotipificação dos isolados de Salmonella Enteritidis

    Directory of Open Access Journals (Sweden)

    Aldemir Reginato Ribeiro

    2007-06-01

    Full Text Available The present study was carried out to evaluate the occurrence of Salmonellae in raw broiler parts and to determine the antimicrobial resistance profile of the isolated strains. Twenty-four (39.3% broiler parts samples were positive for Salmonella and twenty-five Salmonella strains were isolated, since two different serovars were detected in one single positive sample. Salmonella Enteritidis was the most prevalent serovar. Among Salmonella Enteritidis isolates, 95.2% belonged to Phage Type 4 (PT4 (20/21 and 4.8% to PT7 (1/21. Twenty-two (88% strains of Salmonella were resistant to at least one antimicrobial agent, generating eight different resistance patterns. The S. Typhimurium (n: 1 and S. Hadar (n: 3 isolates presented multiple resistance. Three S. Enteritidis isolates were susceptible to all antimicrobials tested, two were resistant only to tetracycline. The high prevalence of Salmonella in the broiler parts strenghtens the importance of the use of good manufacturing practices (GMP, and HACCP. The results also emphasize the need for the responsible use of antimicrobials in animal production.Este trabalho foi conduzido para avaliar a ocorrência de Salmonella em cortes de frango e para determinar o perfil de resistência antimicrobiana das cepas isoladas. Vinte e quatro (39,3% cortes de frango foram positivas para Salmonella, tendo sido isoladas vinte e cinco cepas de Salmonella, uma vez que em uma amostra isolaram-se dois sorovares. Salmonella Enteritidis foi o sorovar prevalente. Entre as Salmonella Enteritidis isoladas, 95,2% pertencem ao Fagotipo 4 (PT4 (20/21 e 4,8% ao PT7 (1/21. Vinte e duas (88% cepas de Salmonella foram resistentes a pelo menos um agente antimicrobiano e oito diferentes padrões de resistência foram observados. S. Typhimurium (n:1 e S. Hadar (n: 3, apresentaram múltipla resistência. Três cepas de S. Enteritidis foram sensíveis a todos os antimicrobianos e duas resistentes somente a tetraciclina. A elevada ocorr

  6. Salmonella Infections - Multiple Languages

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Salmonella Infections URL of this page: https://medlineplus.gov/ ... V W XYZ List of All Topics All Salmonella Infections - Multiple Languages To use the sharing features ...

  7. Oral delivery of the Sj23LHD-GST antigen by Salmonella typhimurium type III secretion system protects against Schistosoma japonicum infection in mice.

    Directory of Open Access Journals (Sweden)

    Guo Chen

    2011-09-01

    Full Text Available BACKGROUND: Schistosomiasis japonica is a zoonotic parasitic disease and oral vaccine delivery system would be benefit for prevention of this disease. Although attenuated salmonella has been used as an antigen expression vector for oral vaccine development, the membrane-bound vacuoles in which bacteria reside hinders the presentation of expressed heterologous antigens to the major histocompatibility complex (MHC molecules. The present work used an attenuated Salmonella typhimurium strain VNP20009 to secretory expression of Sj23LHDGST bivalent antigen from Schistosoma japonicum and tested the protective efficacy against S. japonicum infection in orally immunized mice. METHODOLOGY/PRINCIPAL FINDINGS: Promoters (nirB or pagC were used to express the antigen (Sj23LHDGST and the Salmonella type III or α-hemolysin secretion system was employed to secrete it. The immunoblotting analysis and fluorescent microscopy revealed that the antigen was effectively expressed and delivered to the cytosol of macrophages in vitro. Among recombinant vaccine strains, an engineered VNP20009 which expressed the antigen by nirB promoter and secreted it through type III secretion system (nirB-sopE(1-104-Sj23LHD-GST efficiently protected against S. japonicum infection in a mouse model. This strain elicited a predominantly IgG(2a antibody response and a markedly increase in the production of IL-12 and IFN-γ. The flow cytometric analysis demonstrated that this strain caused T cell activation as evidenced by significantly increased expression of CD44 and CD69. CONCLUSION/SIGNIFICANCE: Oral delivery of antigen by nirB-driven Salmonella typhimurium type III secretion system is a novel, safe, inexpensive, efficient and convenient approach for schistosome vaccine development.

  8. 9 CFR 113.123 - Salmonella Dublin Bacterin.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Dublin Bacterin. 113.123... Inactivated Bacterial Products § 113.123 Salmonella Dublin Bacterin. Salmonella Dublin Bacterin shall be prepared from a culture of Salmonella dublin which has been inactivated and is nontoxic. Each serial of...

  9. The Asd+-DadB+ Dual-Plasmid System Offers a Novel Means To Deliver Multiple Protective Antigens by a Recombinant Attenuated Salmonella Vaccine

    Science.gov (United States)

    Xin, Wei; Wanda, Soo-Young; Zhang, Xiangmin; Santander, Javier; Scarpellini, Giorgio; Ellis, Karen; Alamuri, Praveen

    2012-01-01

    We developed means to deliver multiple heterologous antigens on dual plasmids with non-antibiotic-resistance markers in a single recombinant attenuated vaccine strain of Salmonella enterica serotype Typhimurium. The first component of this delivery system is a strain of S. Typhimurium carrying genomic deletions in alr, dadB, and asd, resulting in obligate requirements for diaminopimelic acid (DAP) and d-alanine for growth. The second component is the Asd+-DadB+ plasmid pair carrying wild-type copies of asdA and dadB, respectively, to complement the mutations. To evaluate the protection efficacy of the dual-plasmid vaccine, S. Typhimurium strain χ9760 (a strain with multiple attenuating mutations: Δasd Δalr ΔdadB ΔrecF) was transformed with Asd+ and DadB+ plasmids specifying pneumococcal antigens PspA and PspC, respectively. Both plasmids were stable in χ9760 for 50 generations when grown in nonselective medium. This was significantly (P < 0.05) greater than the stability seen in its recF+ counterpart χ9590 and could be attributed to reduced interplasmid recombination in χ9760. Oral immunization of BALB/c mice with 1 × 109 CFU of χ9760 (carrying Asd+-PspA and DadB+-PspC plasmids) elicited a dominant Th1-type serum IgG response against both antigens and protected mice against intraperitoneal challenge with 200 50% lethal doses (LD50s) of virulent Streptococcus pneumoniae strain WU2 or intravenous challenge with 100 LD50s of virulent S. pneumoniae strain L81905 or intranasal challenge with a lethal dose of S. pneumoniae A66.1 in a pneumonia model. Protection offered by χ9760 was superior to that offered by the mixture of two strains, χ9828 (Asd+-PspA) and χ11026 (DadB+-PspC). This novel dual-plasmid system marks a remarkable improvement in the development of live bacterial vaccines. PMID:22868499

  10. The Asd(+)-DadB(+) dual-plasmid system offers a novel means to deliver multiple protective antigens by a recombinant attenuated Salmonella vaccine.

    Science.gov (United States)

    Xin, Wei; Wanda, Soo-Young; Zhang, Xiangmin; Santander, Javier; Scarpellini, Giorgio; Ellis, Karen; Alamuri, Praveen; Curtiss, Roy

    2012-10-01

    We developed means to deliver multiple heterologous antigens on dual plasmids with non-antibiotic-resistance markers in a single recombinant attenuated vaccine strain of Salmonella enterica serotype Typhimurium. The first component of this delivery system is a strain of S. Typhimurium carrying genomic deletions in alr, dadB, and asd, resulting in obligate requirements for diaminopimelic acid (DAP) and d-alanine for growth. The second component is the Asd(+)-DadB(+) plasmid pair carrying wild-type copies of asdA and dadB, respectively, to complement the mutations. To evaluate the protection efficacy of the dual-plasmid vaccine, S. Typhimurium strain χ9760 (a strain with multiple attenuating mutations: Δasd Δalr ΔdadB ΔrecF) was transformed with Asd(+) and DadB(+) plasmids specifying pneumococcal antigens PspA and PspC, respectively. Both plasmids were stable in χ9760 for 50 generations when grown in nonselective medium. This was significantly (P < 0.05) greater than the stability seen in its recF(+) counterpart χ9590 and could be attributed to reduced interplasmid recombination in χ9760. Oral immunization of BALB/c mice with 1 × 10(9) CFU of χ9760 (carrying Asd(+)-PspA and DadB(+)-PspC plasmids) elicited a dominant Th1-type serum IgG response against both antigens and protected mice against intraperitoneal challenge with 200 50% lethal doses (LD(50)s) of virulent Streptococcus pneumoniae strain WU2 or intravenous challenge with 100 LD(50)s of virulent S. pneumoniae strain L81905 or intranasal challenge with a lethal dose of S. pneumoniae A66.1 in a pneumonia model. Protection offered by χ9760 was superior to that offered by the mixture of two strains, χ9828 (Asd(+)-PspA) and χ11026 (DadB(+)-PspC). This novel dual-plasmid system marks a remarkable improvement in the development of live bacterial vaccines.

  11. Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI on typing of Salmonella

    NARCIS (Netherlands)

    Korver H; Raes M; Maas HME; Ward LR; Wannet WJB; Henken AM; MGB; LIS

    2002-01-01

    Test resultaten van Salmonella sero- en faagtypering en antimicrobiele gevoeligheidsbepalingen door de Nationale Referentie Laboratoria voor Salmonella in de Lidstaten van de Europese Unie en EnterNet Laboratoria: Ringonderzoek VI (2001) voor Salmonella. Een zesde ringonderzoek betreffende de

  12. Mulberry Leaf Extract Attenuates Oxidative Stress-Mediated Testosterone Depletion in Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Hajizadeh

    2014-03-01

    Full Text Available Background: It has been proposed that oxidative stress may contribute to the development of testicular abnormalities in diabetes. Morus alba leaf extract (MAE has hypoglycemic and antioxidant properties. We, therefore, explored the impact of the administration of MAE on steroidogenesis in diabetic rats. Methods: To address this hypothesis, we measured the serum level of glucose, insulin, and free testosterone (Ts as well as oxidative stress parameters (including glutathione peroxidase, glutathione reductase, total antioxidant capacity, and malondialdehyde in the testis of control, untreated and MAE-treated (1 g/day/kg diabetic rats. In order to determine the likely mechanism of MAE action on Ts levels, we analyzed the quantitative mRNA expression level of the two key steroidogenic proteins, namely steroid acute regulatory protein (StAR and P450 cholesterol side-chain cleavage enzyme (P450scc, by real-time PCR. Results: The MAE-treated diabetic rats had significantly decreased glucose levels and on the other hand increased insulin and free Ts levels than the untreated diabetic rats. In addition, the administration of MAE to the diabetic rats restored the oxidative stress parameters toward control. Induction of diabetes decreased testicular StAR mRNA expression by 66% and MAE treatment enhanced mRNA expression to the same level of the control group. However, the expression of P540scc was not significantly decreased in the diabetic group as compared to the control group. Conclusion: Our findings indicated that MAE significantly increased Ts production in the diabetic rats, probably through the induction of StAR mRNA expression levels. Administration of MAE to experimental models of diabetes can effectively attenuate oxidative stress-mediated testosterone depletion. Please cite this article as: Hajizadeh MR, Eftekhar E, Zal F, Jaffarian A, Mostafavi-Pour Z. Mulberry Leaf Extract Attenuates Oxidative Stress-Mediated Testosterone Depletion in

  13. Survival of Salmonella Newport in oysters.

    Science.gov (United States)

    Morrison, Christopher M; Armstrong, Alexandra E; Evans, Sanford; Mild, Rita M; Langdon, Christopher J; Joens, Lynn A

    2011-08-02

    Salmonella enterica is the leading cause of laboratory-confirmed foodborne illness in the United States and raw shellfish consumption is a commonly implicated source of gastrointestinal pathogens. A 2005 epidemiological study done in our laboratory by Brands et al., showed that oysters in the United States are contaminated with Salmonella, and in particular, a specific strain of the Newport serovar. This work sought to further investigate the host-microbe interactions between Salmonella Newport and oysters. A procedure was developed to reliably and repeatedly expose oysters to enteric bacteria and quantify the subsequent levels of bacterial survival. The results show that 10 days after an exposure to Salmonella Newport, an average concentration of 3.7 × 10(3)CFU/g remains within the oyster meat, and even after 60 days there still can be more than 10(2)CFU/g remaining. However, the strain of Newport that predominated in the market survey done by Brands et al. does not survive within oysters or the estuarine environment better than any other strains of Salmonella we tested. Using this same methodology, we compared Salmonella Newport's ability to survive within oysters to a non-pathogenic strain of E. coli and found that after 10 days the concentration of Salmonella was 200-times greater than that of E. coli. We also compared those same strains of Salmonella and E. coli in a depuration process to determine if a constant 120 L/h flux of clean seawater could significantly reduce the concentration of bacteria within oysters and found that after 3 days the oysters retained over 10(4)CFU/g of Salmonella while the oysters exposed to the non-pathogenic strain of E. coli contained 100-times less bacteria. Overall, the results of this study demonstrate that any of the clinically relevant serovars of Salmonella can survive within oysters for significant periods of time after just one exposure event. Based on the drastic differences in survivability between Salmonella and a non

  14. Prediction of Salmonella carcass contamination by a comparative quantitative analysis of E. coli and Salmonella during pig slaughter

    DEFF Research Database (Denmark)

    Nauta, Maarten; Barfod, Kristen; Hald, Tine

    2013-01-01

    Salmonella concentrations. It is concluded that the faecal carriage of Salmonella together with the faecal contamination of carcasses, as predicted from E. coli data in the animal faeces and hygiene performance of the slaughterhouse, is not sufficient to explain carcass contamination with Salmonella. Our...... extensive data set showed that other factors than the observed faecal carriage of Salmonella by the individual animals brought to slaughter, play a more important role in the Salmonella carcass contamination of pork.......Faecal contamination of carcasses in the slaughterhouse is generally considered to be the source of Salmonella on pork. In this study the hygiene indicator Escherichia coli is used to quantify faecal contamination of carcasses and it is hypothesized that it can be used to predict the quantitative...

  15. TNFα/IFNγ Mediated Intestinal Epithelial Barrier Dysfunction Is Attenuated by MicroRNA-93 Downregulation of PTK6 in Mouse Colonic Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Ricci J Haines

    Full Text Available Since inflammatory bowel diseases (IBD represent significant morbidity and mortality in the US, the need for defining novel drug targets and inflammatory mechanisms would be of considerable benefit. Although protein tyrosine kinase 6 (PTK6, also known as breast tumor kinase BRK has been primarily studied in an oncogenic context, it was noted that PTK6 null mice exhibited significantly enhanced colonic epithelial barrier function. Considering that the inflammatory functions of PTK6 have not yet been explored, we hypothesized that cytokines responsible for mediating IBD, such as TNFα/IFNγ, may solicit the action of PTK6 to alter barrier function. After first assessing critical mediators of TNFα/IFNγ driven epithelial barrier dysfunction, we further explored the possibility of PTK6 in this inflammatory context. In this report, we showed that PTK6 siRNA and PTK6 null young adult mouse colonic epithelial cells (YAMC exhibited significant attenuation of TNFα/IFNγ induced barrier dysfunction as measured by electric cell-substrate impedance sensing (ECIS assay and permeability assays. In addition, PTK6 null cells transfected with PTK6 cDNA displayed restored barrier dysfunction in response to TNFα/IFNγ, while the cells transfected with vector alone showed similar attenuation of barrier dysfunction. Furthermore, using subcellular fractionation and immunocytochemistry experiments, we found that PTK6 plays a role in FoxO1 nuclear accumulation leading to down-regulation of claudin-3, a tight junction protein. Moreover, we searched for relevant miRNA candidates putative for targeting PTK6 in order to identify and assess the impact of microRNA that target PTK6 with respect to TNFα/IFNγ induced barrier dysfunction. Subsequently, we assayed likely targets and determined their effectiveness in attenuating PTK6 expression as well as cytokine induced barrier dysfunction. Results showed that miR-93 reduced PTK6 expression and attenuated TNF

  16. Genome-wide screen for salmonella genes required for long-term systemic infection of the mouse.

    Directory of Open Access Journals (Sweden)

    2006-02-01

    Full Text Available A microarray-based negative selection screen was performed to identify Salmonella enterica serovar Typhimurium (serovar Typhimurium genes that contribute to long-term systemic infection in 129X1/SvJ (Nramp1(r mice. A high-complexity transposon-mutagenized library was used to infect mice intraperitoneally, and the selective disappearance of mutants was monitored after 7, 14, 21, and 28 d postinfection. One hundred and eighteen genes were identified to contribute to serovar Typhimurium infection of the spleens of mice by 28 d postinfection. The negatively selected mutants represent many known aspects of Salmonella physiology and pathogenesis, although the majority of the identified genes are of putative or unknown function. Approximately 30% of the negatively selected genes correspond to horizontally acquired regions such as those within Salmonella pathogenicity islands (SPI 1-5, prophages (Gifsy-1 and -2 and remnant, and the pSLT virulence plasmid. In addition, mutations in genes responsible for outer membrane structure and remodeling, such as LPS- and PhoP-regulated and fimbrial genes, were also selected against. Competitive index experiments demonstrated that the secreted SPI2 effectors SseK2 and SseJ as well as the SPI4 locus are attenuated relative to wild-type bacteria during systemic infection. Interestingly, several SPI1-encoded type III secretion system effectors/translocases are required by serovar Typhimurium to establish and, unexpectedly, to persist systemically, challenging the present description of Salmonella pathogenesis. Moreover, we observed a progressive selection against serovar Typhimurium mutants based upon the duration of the infection, suggesting that different classes of genes may be required at distinct stages of infection. Overall, these data indicate that Salmonella long-term systemic infection in the mouse requires a diverse repertoire of virulence factors. This diversity of genes presumably reflects the fact that

  17. Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI on typing of Salmonella

    NARCIS (Netherlands)

    Korver H; Raes M; Maas HME; Ward LR; Wannet WJB; Henken AM; PHLS-Colindale/London; MGB; LIS

    2002-01-01

    Test results of Salmonella sero- and phage typing and antimicrobial susceptibility testing by the National Reference Laboratories for Salmonella in the Member States of the European Union and the EnterNet Laboratories: Collaborative study VI (2001) for Salmonella. The sixth collaborative typing

  18. Thermal inactivation of eight Salmonella serotypes on dry corn flour.

    OpenAIRE

    VanCauwenberge, J E; Bothast, R J; Kwolek, W F

    1981-01-01

    Dry heat was used to inactivate Salmonella newington, Salmonella typhimurium, Salmonella anatum, Salmonella kentucky, Salmonella cubana, Salmonella seftenberg, Salmonella thompson, and Salmonella tennessee in corn flour at 10 and 15% moisture. The flour was spray inoculated at 10(5) Salmonella cells per g and then stored at 49 degrees C (120 degrees F); viable Salmonella cells were counted on Trypticase (BBL Microbiology Systems) soy agar plates every 30 min for the first 4 h and then at 4-h ...

  19. In vitro transfer of multiple resistance observed in vivo during a Salmonella london epidemic.

    Science.gov (United States)

    Lantos, J; Marjai, E

    1980-01-01

    Between 1976 and 1978, waves of Salmonella london infections conveyed by raw meat and meat products were observed. The strains isolated during the epidemic were first susceptible then developed multiple antibiotic resistance. The identical antibiotic resistance patterns of the strain and their more frequent occurrence in hospital environments indicated plasmid-mediated resistance. R-plasmid transfer, minimum inhibition concentration and resistance elimination were studied in representative strains. The resistant S. london strain and transconjugants of Escherichia coli rendered resistant were compared. The results proved that multiple resistance was plasmid-mediated.

  20. An incomplete TCA cycle increases survival of Salmonella Typhimurium during infection of resting and activated murine macrophages.

    Science.gov (United States)

    Bowden, Steven D; Ramachandran, Vinoy K; Knudsen, Gitte M; Hinton, Jay C D; Thompson, Arthur

    2010-11-08

    In comparison to the comprehensive analyses performed on virulence gene expression, regulation and action, the intracellular metabolism of Salmonella during infection is a relatively under-studied area. We investigated the role of the tricarboxylic acid (TCA) cycle in the intracellular replication of Salmonella Typhimurium in resting and activated macrophages, epithelial cells, and during infection of mice. We constructed deletion mutations of 5 TCA cycle genes in S. Typhimurium including gltA, mdh, sdhCDAB, sucAB, and sucCD. We found that the mutants exhibited increased net intracellular replication in resting and activated murine macrophages compared to the wild-type. In contrast, an epithelial cell infection model showed that the S. Typhimurium ΔsucCD and ΔgltA strains had reduced net intracellular replication compared to the wild-type. The glyoxylate shunt was not responsible for the net increased replication of the TCA cycle mutants within resting macrophages. We also confirmed that, in a murine infection model, the S. Typhimurium ΔsucAB and ΔsucCD strains are attenuated for virulence. Our results suggest that disruption of the TCA cycle increases the ability of S. Typhimurium to survive within resting and activated murine macrophages. In contrast, epithelial cells are non-phagocytic cells and unlike macrophages cannot mount an oxidative and nitrosative defence response against pathogens; our results show that in HeLa cells the S. Typhimurium TCA cycle mutant strains show reduced or no change in intracellular levels compared to the wild-type. The attenuation of the S. Typhimurium ΔsucAB and ΔsucCD mutants in mice, compared to their increased net intracellular replication in resting and activated macrophages suggest that Salmonella may encounter environments within the host where a complete TCA cycle is advantageous.

  1. Assessment of Salmonella survival in dry-cured Italian salami.

    Science.gov (United States)

    Bonardi, S; Bruini, I; Bolzoni, L; Cozzolino, P; Pierantoni, M; Brindani, F; Bellotti, P; Renzi, M; Pongolini, S

    2017-12-04

    The inactivation of Salmonella during curing of Italian traditional pork salami was investigated. A total of 150 batches of ground raw meat (GRM) used for salami manufacturing by four producers were tested for Salmonella by real-time PCR followed by ISO 6579 cultural confirmation and MPN enumeration. Salami produced with Salmonella positive GRMs were re-tested at the end of their curing period. Aw, pH and NaCl content were also measured. Detection of Salmonella was performed testing both 25 and 50g of the samples. By Real-Time PCR 37% of the GRMs resulted positive, but cultural detection of Salmonella was obtained in 14% of the samples only. Salmonella enumeration ranged from 31 MPN/g to Salmonella in 100% of all positive samples, vs. 62% of ISO-25g. Salami made of the contaminated GRMs were 29% Salmonella-positive, as most batches of salami produced with Salmonella-positive GRMs resulted negative after regular curing (20-48days). Overall, 13% of salami produced with Salmonella-contaminated GRMs were positive. They belonged to six batches, which turned out negative after prolonged curing ranging between 49 and 86days. Salmonella enumeration in salami ranged from 8.7 MPN/g to Salmonella in cured salami (p value: >0.05). The most common Salmonella serovars in GRMs were Derby (52%), Typhimurium monophasic variant 4, (Barbuti et al., 1993), 12:i:- (19%) and Stanley (10%). Salmonella Derby (56%), London, Branderup, Panama (13%, respectively) and Goldcoast (6%) were most frequent in cured salami. The study showed negative correlation between real-time CT values and cultural confirmation of Salmonella, as well as the importance of sample size for Salmonella detection. Among considered factors with possible effect on the occurrence of Salmonella in salami, statistical analysis revealed a role for aw in salami and for Salmonella load in GRMs, while pH and NaCl content did not significantly affect the probability of finding Salmonella in dry-cured salami in the context of

  2. Autophagy Facilitates Salmonella Replication in HeLa Cells

    Science.gov (United States)

    Yu, Hong B.; Croxen, Matthew A.; Marchiando, Amanda M.; Ferreira, Rosana B. R.; Cadwell, Ken; Foster, Leonard J.; Finlay, B. Brett

    2014-01-01

    ABSTRACT Autophagy is a process whereby a double-membrane structure (autophagosome) engulfs unnecessary cytosolic proteins, organelles, and invading pathogens and delivers them to the lysosome for degradation. We examined the fate of cytosolic Salmonella targeted by autophagy and found that autophagy-targeted Salmonella present in the cytosol of HeLa cells correlates with intracellular bacterial replication. Real-time analyses revealed that a subset of cytosolic Salmonella extensively associates with autophagy components p62 and/or LC3 and replicates quickly, whereas intravacuolar Salmonella shows no or very limited association with p62 or LC3 and replicates much more slowly. Replication of cytosolic Salmonella in HeLa cells is significantly decreased when autophagy components are depleted. Eventually, hyperreplication of cytosolic Salmonella potentiates cell detachment, facilitating the dissemination of Salmonella to neighboring cells. We propose that Salmonella benefits from autophagy for its cytosolic replication in HeLa cells. PMID:24618251

  3. A novel chalcone derivative attenuates the diabetes-induced renal injury via inhibition of high glucose-mediated inflammatory response and macrophage infiltration

    International Nuclear Information System (INIS)

    Fang, Qilu; Zhao, Leping; Wang, Yi; Zhang, Yali; Li, Zhaoyu; Pan, Yong; Kanchana, Karvannan; Wang, Jingying; Tong, Chao; Li, Dan; Liang, Guang

    2015-01-01

    Inflammation plays a central role in the development and progression of diabetic nephropathy (DN). Researches on novel anti-inflammatory agents may offer new opportunities for the treatment of DN. We previously found a chalcone derivative L6H21 could inhibit LPS-induced cytokine release from macrophages. The aim of this study was to investigate whether L6H21 could ameliorate the high glucose-mediated inflammation in NRK-52E cells and attenuate the inflammation-mediated renal injury. According to the results, L6H21 showed a great inhibitory effect on the expression of pro-inflammatory cytokines, cell adhesion molecules, chemokines, and macrophage adhesion via down-regulation of NF-κB/MAPKs activity in high glucose-stimulated renal NRK-52E cells. Further, in vivo oral administration with L6H21 at a dosage of 20 mg/kg/2 days showed a decreased expression of pro-inflammatory cytokines, cell adhesion molecules, which subsequently contributed to the inhibition on renal macrophage infiltration, the reduction of serum creatinine and BUN levels, and the improvement on the fibrosis and pathological changes in the renal tissues of diabetic mice. These findings provided that chalcone derived L6H21 may be a promising anti-inflammatory agent and have the potential in the therapy of diabetic nephropathy, and importantly, MAPK/NF-κB signaling system may be a novel therapeutic target for human DN in the future. - Highlights: • Inflammation plays a central role in the development of diabetic nephropathy. • Compound L6H21 reduced the high glucose-mediated inflammation in NRK-52E cells. • Compound L6H21 attenuated the inflammation-mediated renal injury. • L6H21 exhibited anti-inflammatory effects via inactivation of NF-κB/MAPKs. • MAPKs/NF-κB may be a novel therapeutic target in diabetic nephropathy treatment

  4. A novel chalcone derivative attenuates the diabetes-induced renal injury via inhibition of high glucose-mediated inflammatory response and macrophage infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Qilu [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Zhao, Leping [Department of Pharmacy, the Affiliated Yueqing Hospital, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wang, Yi; Zhang, Yali [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Li, Zhaoyu [Department of International High School, Shanghai Jiaotong University Nanyang Affiliated (Kunshan) School, Minhang District, Shanghai (China); Pan, Yong; Kanchana, Karvannan; Wang, Jingying; Tong, Chao [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Li, Dan, E-mail: yqyyld@163.com [Department of Nephrology, the Affiliated Yueqing Hospital, Wenzhou Medical University, Wenzhou, Zhejiang (China); Liang, Guang, E-mail: wzmcliangguang@163.com [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China)

    2015-01-15

    Inflammation plays a central role in the development and progression of diabetic nephropathy (DN). Researches on novel anti-inflammatory agents may offer new opportunities for the treatment of DN. We previously found a chalcone derivative L6H21 could inhibit LPS-induced cytokine release from macrophages. The aim of this study was to investigate whether L6H21 could ameliorate the high glucose-mediated inflammation in NRK-52E cells and attenuate the inflammation-mediated renal injury. According to the results, L6H21 showed a great inhibitory effect on the expression of pro-inflammatory cytokines, cell adhesion molecules, chemokines, and macrophage adhesion via down-regulation of NF-κB/MAPKs activity in high glucose-stimulated renal NRK-52E cells. Further, in vivo oral administration with L6H21 at a dosage of 20 mg/kg/2 days showed a decreased expression of pro-inflammatory cytokines, cell adhesion molecules, which subsequently contributed to the inhibition on renal macrophage infiltration, the reduction of serum creatinine and BUN levels, and the improvement on the fibrosis and pathological changes in the renal tissues of diabetic mice. These findings provided that chalcone derived L6H21 may be a promising anti-inflammatory agent and have the potential in the therapy of diabetic nephropathy, and importantly, MAPK/NF-κB signaling system may be a novel therapeutic target for human DN in the future. - Highlights: • Inflammation plays a central role in the development of diabetic nephropathy. • Compound L6H21 reduced the high glucose-mediated inflammation in NRK-52E cells. • Compound L6H21 attenuated the inflammation-mediated renal injury. • L6H21 exhibited anti-inflammatory effects via inactivation of NF-κB/MAPKs. • MAPKs/NF-κB may be a novel therapeutic target in diabetic nephropathy treatment.

  5. In situ characterization and analysis of Salmonella biofilm formation under meat processing environments using a combined microscopic and spectroscopic approach.

    Science.gov (United States)

    Wang, Huhu; Ding, Shijie; Wang, Guangyu; Xu, Xinglian; Zhou, Guanghong

    2013-11-01

    Salmonella biofilm on food-contact surfaces present on food processing facilities may serve as a source of cross-contamination. In our work, biofilm formation by multi-strains of meat-borne Salmonella incubated at 20 °C, as well as the composition and distribution of extracellular polymeric substances (EPS), were investigated in situ by combining confocal laser scanning microscopy (CLSM), scanning electron microscope (SEM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and Raman spectroscopy. A standard laboratory culture medium (tryptic soy broth, TSB) was used and compared with an actual meat substrate (meat thawing-loss broth, MTLB). The results indicated that Salmonella grown in both media were able to form biofilms on stainless steel surfaces via building a three-dimensional structure with multilayers of cells. Although the number of biofilm cells grown in MTLB was less than that in TSB, the cell numbers in MTLB was adequate to form a steady and mature biofilm. Salmonella grown in MTLB showed "cloud-shaped" morphology in the mature biofilm, whereas when grown in TSB appeared "reticular-shaped". The ATR-FTIR and Raman analysis revealed a completely different chemical composition between biofilms and the corresponding planktonic cells, and some important differences in biofilms grown in MTLB and in TSB. Importantly, our findings suggested that the progress towards a mature Salmonella biofilm on stainless steel surfaces may be associated with the production of the EPS matrix, mainly consisting of polysaccharides and proteins, which may serve as useful markers of biofilm formation. Our work indicated that a combination of these non-destructive techniques provided new insights into the formation of Salmonella biofilm matrix. © 2013.

  6. Antigen 43-mediated autotransporter display, a versatile bacterial cell surface presentation system

    DEFF Research Database (Denmark)

    Kjærgaard, Kristian; Hasman, Henrik; Schembri, Mark

    2002-01-01

    bridges does not interfere with surface display, and Ag43 chimeras are correctly processed into alpha- and beta-modules, offering optional and easy release of the chimeric alpha-subunits. Furthermore, Ag43 can be displayed in many gram-negative bacteria. This feature is exploited for display of our...... chimeras in an attenuated Salmonella strain....

  7. Study of Salmonella Typhimurium infection in laying hens

    Directory of Open Access Journals (Sweden)

    Kapil eChousalkar

    2016-02-01

    Full Text Available Members of Salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. In Australia, Salmonella Typhimurium is frequently involved in egg and egg product related foodborne illness and Salmonella Mbandaka has also been found to be a contaminant of the layer farm environment. The ability possessed by Salmonella Enteritidis to colonise reproductive organs and contaminate developing eggs has been well described. However, there are few studies investigating this ability for Salmonella Typhimurium. The hypothesis of this study was that the Salmonella Typhimurium can colonise the gut for a prolonged period of time and that horizontal infection through feces is the main route of egg contamination. At 14 weeks of age hens were orally infected with either S. Typhimurium PT 9 or S. Typhimurium PT 9 and Salmonella Mbandaka. Salmonella shedding in feces and eggs was monitored for 15 weeks post infection. Egg shell surface and internal contents of eggs laid by infected hens were cultured independently for detection of Salmonella spp. The mean Salmonella load in feces ranged from 1.54 to 63.35 and 0.31 to 98.38 most probable number/g (MPN/g in the S. Typhimurium and S. Typhimurium + S. Mbandaka group respectively. No correlation was found between mean fecal Salmonella load and frequency of egg shell contamination. Egg shell contamination was higher in S. Typhimurium + S. Mbandaka infected group (7.2% Typhimurium, 14.1% Mbandaka compared to birds infected with S. Typhimurium (5.66% however, co-infection had no significant impact on egg contamination by S. Typhimurium. Throughout the study Salmonella was not recovered from internal contents of eggs laid by hens. Salmonella was isolated from different segments of oviduct of hens from both the groups, however pathology was not observed on microscopic examination. This study investigated Salmonella shedding for up to 15 weeks p.i which is a longer period of

  8. Host lysozyme-mediated lysis of Lactococcus lactis facilitates delivery of colitis-attenuating superoxide dismutase to inflamed colons

    Science.gov (United States)

    Ballal, Sonia A.; Veiga, Patrick; Fenn, Kathrin; Michaud, Monia; Kim, Jason H.; Gallini, Carey Ann; Glickman, Jonathan N.; Quéré, Gaëlle; Garault, Peggy; Béal, Chloé; Derrien, Muriel; Courtin, Pascal; Kulakauskas, Saulius; Chapot-Chartier, Marie-Pierre; van Hylckama Vlieg, Johan; Garrett, Wendy S.

    2015-01-01

    Beneficial microbes that target molecules and pathways, such as oxidative stress, which can negatively affect both host and microbiota, may hold promise as an inflammatory bowel disease therapy. Prior work showed that a five-strain fermented milk product (FMP) improved colitis in T-bet−/− Rag2−/− mice. By varying the number of strains used in the FMP, we found that Lactococcus lactis I-1631 was sufficient to ameliorate colitis. Using comparative genomic analyses, we identified genes unique to L. lactis I-1631 involved in oxygen respiration. Respiration of oxygen results in reactive oxygen species (ROS) generation. Also, ROS are produced at high levels during intestinal inflammation and cause tissue damage. L. lactis I-1631 possesses genes encoding enzymes that detoxify ROS, such as superoxide dismutase (SodA). Thus, we hypothesized that lactococcal SodA played a role in attenuating colitis. Inactivation of the sodA gene abolished L. lactis I-1631’s beneficial effect in the T-bet−/− Rag2−/− model. Similar effects were obtained in two additional colonic inflammation models, Il10−/− mice and dextran sulfate sodium-treated mice. Efforts to understand how a lipophobic superoxide anion (O2−) can be detoxified by cytoplasmic lactoccocal SodA led to the finding that host antimicrobial-mediated lysis is a prerequisite for SodA release and SodA’s extracytoplasmic O2− scavenging. L. lactis I-1631 may represent a promising vehicle to deliver antioxidant, colitis-attenuating SodA to the inflamed intestinal mucosa, and host antimicrobials may play a critical role in mediating SodA’s bioaccessibility. PMID:26056274

  9. Comparing validation of four ELISAsystems for detection of Salmonella Derby- and Salmonella Infantis-infected pigs

    OpenAIRE

    Rösler, Uwe; Szabo, Istvan; Matthies, Claudia; Albrecht, Kerstin; Leffler, Kerstin; Scherer, Kathrin; Nöckler, Karsten; Lehmann, Jörg; Methner, Ulrich; Hensel, Andreas

    2018-01-01

    The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs. Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were ...

  10. Prevalence and antibiotic resistance of Salmonella Enteritidis and Salmonella Typhimurium in raw chicken meat at retail markets in Malaysia.

    Science.gov (United States)

    Thung, T Y; Mahyudin, N A; Basri, D F; Wan Mohamed Radzi, C W J; Nakaguchi, Y; Nishibuchi, M; Radu, S

    2016-08-01

    Salmonellosis is one of the major food-borne diseases in many countries. This study was carried out to determine the occurrence of Salmonella spp., Salmonella Enteritidis, and Salmonella Typhimurium in raw chicken meat from wet markets and hypermarkets in Selangor, as well as to determine the antibiotic susceptibility profile of S. Enteritidis and S. Typhimurium. The most probable number (MPN) in combination with multiplex polymerase chain reaction (mPCR) method was used to quantify the Salmonella spp., S. Enteritidis, and S. Typhimurium in the samples. The occurrence of Salmonella spp., S. Enteritidis, and S. Typhimurium in 120 chicken meat samples were 20.80%, 6.70%, and 2.50%, respectively with estimated quantity varying from retail chicken meat could be a source of multiple antimicrobial-resistance Salmonella and may constitute a public health concern in Malaysia. © 2016 Poultry Science Association Inc.

  11. Effect of vaccinating breeder chickens with a killed Salmonella vaccine on Salmonella prevalences and loads in breeder and broiler chicken flocks.

    Science.gov (United States)

    Berghaus, R D; Thayer, S G; Maurer, J J; Hofacre, C L

    2011-05-01

    The objective of this study was to evaluate the effect of vaccination of breeder chickens on Salmonella prevalences and loads in breeder and broiler chicken flocks. Chickens housed on six commercial breeder farms were vaccinated with a killed Salmonella vaccine containing Salmonella Typhimurium, Salmonella Enteritidis, and Salmonella Kentucky. Unvaccinated breeders placed on six additional farms served as controls. Eggs from vaccinated and unvaccinated breeder flocks were kept separately in the hatchery, and the resulting chicks were used to populate 58 commercial broiler flock houses by using a pair-matched design. Vaccinated breeder flocks had significantly higher Salmonella-specific antibody titers than did the unvaccinated breeder flocks, although they did not differ significantly with respect to environmental Salmonella prevalences or loads. Broiler flocks that were the progeny of vaccinated breeders had significantly lower Salmonella prevalences and loads than broiler flocks that were the progeny of unvaccinated breeders. After adjusting for sample type and clustering at the farm level, the odds of detecting Salmonella in samples collected from broiler flocks originating from vaccinated breeders were 62% lower (odds ratio [95% confidence interval] = 0.38 [0.21, 0.68]) than in flocks from unvaccinated breeders. In addition, the mean load of culture-positive samples was lower in broilers from vaccinated breeders by 0.30 log most probable number per sample (95% confidence interval of -0.51, -0.09; P = 0.004), corresponding to a 50% decrease in Salmonella loads. In summary, vaccination of broiler breeder pullets increased humoral immunity in the breeders and reduced Salmonella prevalences and loads in their broiler progeny, but did not significantly decrease Salmonella in the breeder farm environment.

  12. Salmonella-secreted Virulence Factors

    Energy Technology Data Exchange (ETDEWEB)

    Heffron, Fred; Niemann, George; Yoon, Hyunjin; Kidwai, Afshan S.; Brown, Roslyn N.; McDermott, Jason E.; Smith, Richard D.; Adkins, Joshua N.

    2011-05-01

    In this short review we discuss secreted virulence factors of Salmonella, which directly affect Salmonella interaction with its host. Salmonella secretes protein to subvert host defenses but also, as discussed, to reduce virulence thereby permitting the bacteria to persist longer and more successfully disperse. The type III secretion system (TTSS) is the best known and well studied of the mechanisms that enable secretion from the bacterial cytoplasm to the host cell cytoplasm. Other secretion systems include outer membrane vesicles, which are present in all Gram-negative bacteria examined to date, two-partner secretion, and type VI secretion will also be addressed. Excellent reviews of Salmonella secreted effectors have focused on themes such as actin rearrangements, vesicular trafficking, ubiquitination, and the activities of the virulence factors themselves. This short review is based on S. Typhimurium infection of mice because it is a model of typhoid like disease in humans. We have organized effectors in terms of events that happen during the infection cycle and how secreted effectors may be involved.

  13. Non-Typhoidal Salmonella Aortitis in a transplant patient

    International Nuclear Information System (INIS)

    Tarif, N.; Azam, M.N.; Mitwalli, Ahmad H.; Al-Wakeel, Jamal S.; El-Kheder, A. Al-Aboud

    2002-01-01

    Non-typhoidal salmonella bacteremia may result in extra gastrointestinallocalization of infection. Aortitis due to non-typhoidal salmonella wasreported to be the cause of 38-42% of all infected abdominal aortitis.Underlying atherosclerosis is a frequent site for salmonella aortitis. Wedescribe here a case of possible salmonella aortitis in a renal transplantpatient. (author)

  14. Test results of Salmonella typing by the National Reference Laboratories for Salmonella in the Member States of the European Union and the EnterNet Laboratories - Collaborative study VII on typing of Salmonella

    NARCIS (Netherlands)

    Korver H; Maas HME; Ward LR; Wannet WJB; Henken AM; MGB; LIS

    2003-01-01

    Het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) organiseerde in samenwerking met Public Health Laboratory Services (PHLS), London, Verenigd Koninkrijk een zevende ringonderzoek aangaande de typering van Salmonella. Zeventien Nationale Referentie

  15. A carbon nanotube immunosensor for Salmonella

    Science.gov (United States)

    Lerner, Mitchell B.; Goldsmith, Brett R.; McMillon, Ronald; Dailey, Jennifer; Pillai, Shreekumar; Singh, Shree R.; Johnson, A. T. Charlie

    2011-12-01

    Antibody-functionalized carbon nanotube devices have been suggested for use as bacterial detectors for monitoring of food purity in transit from the farm to the kitchen. Here we report progress towards that goal by demonstrating specific detection of Salmonella in complex nutrient broth solutions using nanotube transistors functionalized with covalently-bound anti-Salmonella antibodies. The small size of the active device region makes them compatible with integration in large-scale arrays. We find that the on-state current of the transistor is sensitive specifically to the Salmonella concentration and saturates at low concentration (Salmonella and other bacteria types, with no sign of saturation even at much larger concentrations (108 cfu/ml).

  16. The Salmonella enterica Pan-genome

    DEFF Research Database (Denmark)

    Jacobsen, Annika; Hendriksen, Rene S.; Aarestrup, Frank Møller

    2011-01-01

    Salmonella enterica is divided into four subspecies containing a large number of different serovars, several of which are important zoonotic pathogens and some show a high degree of host specificity or host preference. We compare 45 sequenced S. enterica genomes that are publicly available (22......, and the core and pan-genome of Salmonella were estimated to be around 2,800 and 10,000 gene families, respectively. The constructed pan-genomic dendrograms suggest that gene content is often, but not uniformly correlated to serotype. Any given Salmonella strain has a large stable core, whilst...... there is an abundance of accessory genes, including the Salmonella pathogenicity islands (SPIs), transposable elements, phages, and plasmid DNA. We visualize conservation in the genomes in relation to chromosomal location and DNA structural features and find that variation in gene content is localized in a selection...

  17. Salmonella Control Programs in Denmark

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar; Hald, Tine; Wong, Danilo Lo Fo

    2003-01-01

    We describe Salmonella control programs of broiler chickens, layer hens, and pigs in Denmark. Major reductions in the incidence of foodborne human salmonellosis have occurred by integrated control of farms and food processing plants. Disease control has been achieved by monitoring the herds...... and flocks, eliminating infected animals, and diversifying animals (animals and products are processed differently depending on Salmonella status) and animal food products according to the determined risk. In 2001, the Danish society saved U.S.$25.5 million by controlling Salmonella. The total annual...... Salmonella control costs in year 2001 were U.S.$14.1 million (U.S.$0.075/kg of pork and U.S.$0.02/kg of broiler or egg). These costs are paid almost exclusively by the industry. The control principles described are applicable to most industrialized countries with modern intensive farming systems....

  18. A toxin antitoxin system promotes the maintenance of the IncA/C-mobilizable Salmonella Genomic Island 1.

    Science.gov (United States)

    Huguet, Kevin T; Gonnet, Mathieu; Doublet, Benoît; Cloeckaert, Axel

    2016-08-31

    The multidrug resistance Salmonella Genomic Island 1 (SGI1) is an integrative mobilizable element identified in several enterobacterial pathogens. This chromosomal island requires a conjugative IncA/C plasmid to be excised as a circular extrachromosomal form and conjugally mobilized in trans. Preliminary observations suggest stable maintenance of SGI1 in the host chromosome but paradoxically also incompatibility between SGI1 and IncA/C plasmids. Here, using a Salmonella enterica serovar Agona clonal bacterial population as model, we demonstrate that a Toxin-Antitoxin (TA) system encoded by SGI1 plays a critical role in its stable host maintenance when an IncA/C plasmid is concomitantly present. This system, designated sgiAT for Salmonella genomic island 1 Antitoxin and Toxin respectively, thus seems to play a stabilizing role in a situation where SGI1 is susceptible to be lost through plasmid IncA/C-mediated excision. Moreover and for the first time, the incompatibility between SGI1 and IncA/C plasmids was experimentally confirmed.

  19. Phenotypic and molecular characterization of Salmonella serotypes ...

    African Journals Online (AJOL)

    The presence of Salmonella and human pathogens in unpasteurized milk remains a public health hazard. The study reported the phenotypic and molecular characterization of Salmonella serotypes in cow raw milk, cheese and traditional yoghurt marketed for man's consumption in Nigeria. Isolation of Salmonella was done ...

  20. Comparative proteomic analysis of Salmonella enterica serovar Typhimurium ppGpp-deficient mutant to identify a novel virulence protein required for intracellular survival in macrophages

    Directory of Open Access Journals (Sweden)

    Kumagai Yoshinori

    2010-12-01

    Full Text Available Abstract Background The global ppGpp-mediated stringent response in pathogenic bacteria plays an important role in the pathogenesis of bacterial infections. In Salmonella enterica serovar Typhimurium (S. Typhimurium, several genes, including virulence genes, are regulated by ppGpp when bacteria are under the stringent response. To understand the control of virulence genes by ppGpp in S. Typhimurium, agarose 2-dimensional electrophoresis (2-DE combined with mass spectrometry was used and a comprehensive 2-DE reference map of amino acid-starved S. Typhimurium strain SH100, a derivative of ATCC 14028, was established. Results Of the 366 examined spots, 269 proteins were successfully identified. The comparative analysis of the wild-type and ppGpp0 mutant strains revealed 55 proteins, the expression patterns of which were affected by ppGpp. Using a mouse infection model, we further identified a novel virulence-associated factor, STM3169, from the ppGpp-regulated and Salmonella-specific proteins. In addition, Salmonella strains carrying mutations in the gene encoding STM3169 showed growth defects and impaired growth within macrophage-like RAW264.7 cells. Furthermore, we found that expression of stm3169 was controlled by ppGpp and SsrB, a response regulator of the two-component system located on Salmonella pathogenicity island 2. Conclusions A proteomic approach using a 2-DE reference map can prove a powerful tool for analyzing virulence factors and the regulatory network involved in Salmonella pathogenesis. Our results also provide evidence of a global response mediated by ppGpp in S. enterica.

  1. Tentative Colistin Epidemiological Cut-Off Value for Salmonella spp

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Torpdahl, Mia; Zachariasen, Camilla

    2012-01-01

    . Interestingly, Salmonella Dublin and Salmonella Enteritidis belong to the same O-group (O:1, 9,12), suggesting that surface lipopolysaccharides (LPS) of the cell (O-antigen) play a role in colistin susceptibility. The epidemiological cut-off value of >2 mg/L for colistin suggested by European Committee...... on Antimicrobial Susceptibility Testing (EUCAST) is placed inside the distribution for both Salmonella Dublin and Salmonella Enteritidis. All tested Salmonella Dublin isolates, regardless of MIC colistin value, had identical pmrA and pmrB sequences. Missense mutations were found only in pmrA in one Salmonella...

  2. Histopathological analysis of Salmonella chronic carriage in the mouse hepatopancreatobiliary system.

    Directory of Open Access Journals (Sweden)

    Geoffrey Gonzalez-Escobedo

    Full Text Available Salmonella Typhi asymptomatic chronic carriage represents a challenge for the diagnosis and prevention of typhoid fever in endemic areas. Such carriers are thought to be reservoirs for further spread of the disease. Gallbladder carriage has been demonstrated to be mediated by biofilm formation on gallstones and by intracellular persistence in the gallbladder epithelium of mice. In addition, both gallstones and chronic carriage have been associated with chronic inflammation and the development of gallbladder carcinoma. However, the pathogenic relationship between typhoid carriage and the development of pre-malignant and/or malignant lesions in the hepatopancreatobiliary system as well as the host-pathogen interactions occurring during chronic carriage remains unclear. In this study, we monitored the histopathological features of chronic carriage up to 1 year post-infection. Chronic cholecystitis and hepatitis ranging from mild to severe were present in infected mice regardless of the presence of gallstones. Biliary epithelial hyperplasia was observed more commonly in the gallbladder of mice with gallstones (uninfected or infected. However, pre-malignant lesions, atypical hyperplasia and metaplasia of the gallbladder and exocrine pancreas, respectively, were only associated with chronic Salmonella carriage. This study has implications regarding the role of Salmonella chronic infection and inflammation in the development of pre-malignant lesions in the epithelium of the gallbladder and pancreas that could lead to oncogenesis.

  3. A single-tube screen for Salmonella and Shigella.

    Science.gov (United States)

    Procop, Gary W; Wallace, Jacqueline D; Tuohy, Marion J; Lasalvia, Margret M; Addison, Rachel M; Reller, L Barth

    2008-08-01

    Salmonella and Shigella species are routinely sought in stool specimens submitted for culture. It is a common practice to screen lactose-negative colonies by using triple sugar iron agar, lysine iron agar, and Christensen urea agar to determine if further identification is necessary. We designed and evaluated a novel combination of media, which are layered in a single tube, for screening isolates suspected to possibly represent Salmonella or Shigella. We tested this media combination with 106 Salmonella, 56 Shigella, and 56 other gram-negative bacilli. All Salmonella and Shigella isolates tested were appropriately characterized as possible Salmonella or Shigella by using an algorithm developed for use with this media combination. Similarly, 53 (95%) of 56 other gram-negative bacilli were appropriately screened as non -Salmonella and non -Shigella isolates. This unique media combination provides the most important biochemical reactions needed to screen for Salmonella and Shigella in a single-tube format, which decreases labor by two thirds (ie, 1 tube is inoculated vs 3).

  4. Antibody- and TRIM21-dependent intracellular restriction of Salmonella enterica.

    Science.gov (United States)

    Rakebrandt, Nikolas; Lentes, Sabine; Neumann, Heinz; James, Leo C; Neumann-Staubitz, Petra

    2014-11-01

    TRIM21 ('tripartite motif-containing protein 21', Ro52) is a ubiquitously expressed cytosolic Fc receptor, which has a potent role in protective immunity against nonenveloped viruses. TRIM21 mediates intracellular neutralisation of antibody-coated viruses, a process called ADIN (antibody-dependent intracellular neutralisation). Our results reveal a similar mechanism to fight bacterial infections. TRIM21 is recruited to the intracellular pathogen Salmonella enterica in epithelial cells early in infection. TRIM21 does not bind directly to S. enterica, but to antibodies opsonising it. Most importantly, bacterial restriction is dependent on TRIM21 as well as on the opsonisation state of the bacteria. Finally, Salmonella and TRIM21 colocalise with the autophagosomal marker LC3, and intracellular defence is enhanced in starved cells suggesting an involvement of the autophagocytic pathway. Our data extend the protective role of TRIM21 from viruses to bacteria and thereby strengthening the general role of ADIN in cellular immunity. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  5. Salmonella serotype distribution in the Dutch broiler supply chain.

    Science.gov (United States)

    van Asselt, E D; Thissen, J T N M; van der Fels-Klerx, H J

    2009-12-01

    Salmonella serotype distribution can give insight in contamination routes and persistence along a production chain. Therefore, it is important to determine not only Salmonella prevalence but also to specify the serotypes involved at the different stages of the supply chain. For this purpose, data from a national monitoring program in the Netherlands were used to estimate the serotype distribution and to determine whether this distribution differs for the available sampling points in the broiler supply chain. Data covered the period from 2002 to 2005, all slaughterhouses (n = 22), and the following 6 sampling points: departure from hatchery, arrival at the farm, departure from the farm, arrival at the slaughterhouse, departure from the slaughterhouse, and end of processing. Furthermore, retail data for 2005 were used for comparison with slaughterhouse data. The following serotypes were followed throughout the chain: Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Paratyphi B var. Java (Salmonella Java), Salmonella Infantis, Salmonella Virchow, and Salmonella Mbandaka. Results showed that serotype distribution varied significantly throughout the supply chain (P supply chain up to the retail phase.

  6. Reduction of Salmonella in ground chicken using a bacteriophage.

    Science.gov (United States)

    Grant, Ar'Quette; Parveen, Salina; Schwarz, Jurgen; Hashem, Fawzy; Vimini, Bob

    2017-08-01

    This study's goal was to ascertain the effectiveness of a commercially available Salmonella bacteriophage during ground chicken production focusing on: water source, different Salmonella serovars, and time. Salmonella-free boneless, skinless chicken meat was inoculated with 4.0 Log CFU/cm2 of either a cocktail of 3 Salmonella isolates derived from ground chicken (GC) or a cocktail of 3 Salmonella strains not isolated from ground chicken (non-GC). Bacteriophages were spread onto the chicken using sterile tap or filtered water for 30 min or 8 h. Salmonella was recovered using standard plating method. Greater Salmonella reduction was observed when the bacteriophage was diluted in sterile tap water than in sterile filtered water: 0.39 Log CFU/cm2 and 0.23 Log CFU/cm2 reduction after 30 min, respectively (P Salmonella's susceptibility to the bacteriophage, and treatment time. © 2017 Poultry Science Association Inc.

  7. Catecholamines and in vitro growth of pathogenic bacteria: enhancement of growth varies greatly among bacterial species

    Science.gov (United States)

    Belay, Tesfaye; Aviles, Hernan; Vance, Monique; Fountain, Kimberly; Sonnenfeld, Gerald

    2003-01-01

    The purpose of this study was to examine the effects of catecholamines on in vitro growth of a range of bacterial species, including anaerobes. Bacteria tested included: Porphyromonas gingivalis, Bacteriodes fragilis, Shigella boydii, Shigella sonnie, Enterobacter Sp, and Salmonella choleraesuis. The results of the current study indicated that supplementation of bacterial cultures in minimal medium with norepinephrine or epinephrine did not result in increased growth of bacteria. Positive controls involving treatment of Escherichia coli with catecholamines did result in increased growth of that bacterial species. The results of the present study extend previous observations that showed differential capability of catecholamines to enhance bacterial growth in vitro.

  8. Involvement of a putative intercellular signal-recognizing G protein-coupled receptor in the engulfment of Salmonella by the protozoan Tetrahymena

    Directory of Open Access Journals (Sweden)

    P.N. Agbedanu

    2013-07-01

    Full Text Available In an effort to investigate the molecular basis of protozoa engulfment-mediated hypervirulence of Salmonella in cattle, we evaluated protozoan G protein-coupled receptors (GPCRs as transducers of Salmonella engulfment by the model protozoan Tetrahymena. Our laboratory previously demonstrated that non-pathogenic protozoa (including Tetrahymena engulf Salmonella and then exacerbate its virulence in cattle, but the mechanistic details of the phenomenon are not fully understood. GPCRs were investigated since these receptors facilitate phagocytosis of particulates by Tetrahymena, and a GPCR apparently modulates bacterial engulfment for the pathogenic protozoan Entamoeba histolytica. A database search identified three putative Tetrahymena GPCRs, based on sequence homologies and predicted transmembrane domains, that were the focus of this study. Salmonella engulfment by Tetrahymena was assessed in the presence of suramin, a non-specific GPCR inhibitor. Salmonella engulfment was also assessed in Tetrahymena in which expression of putative GPCRs was knocked-down using RNAi. A candidate GPCR was then expressed in a heterologous yeast expression system for further characterization. Our results revealed that Tetrahymena were less efficient at engulfing Salmonella in the presence of suramin. Engulfment was reduced concordantly with a reduction in the density of protozoa. RNAi-based studies revealed that knock-down of one the Tetrahymena GPCRs caused diminished engulfment of Salmonella. Tetrahymena lysates activated this receptor in the heterologous expression system. These data demonstrate that the Tetrahymena receptor is a putative GPCR that facilitates bacterial engulfment by Tetrahymena. Activation of the putative GPCR seemed to be related to protozoan cell density, suggesting that its cognate ligand is an intercellular signaling molecule.

  9. LPS structure and PhoQ activity are important for Salmonella Typhimurium virulence in the Galleria mellonella infection model [corrected].

    Directory of Open Access Journals (Sweden)

    Jennifer K Bender

    Full Text Available The larvae of the wax moth, Galleria mellonella, have been used experimentally to host a range of bacterial and fungal pathogens. In this study we evaluated the suitability of G. mellonella as an alternative animal model of Salmonella infection. Using a range of inoculum doses we established that the LD₅₀ of SalmonellaTyphimurium strain NCTC 12023 was 3.6 × 10³ bacteria per larva. Further, a set of isogenic mutant strains depleted of known virulence factors was tested to identify determinants essential for S. Typhimurium pathogenesis. Mutants depleted of one or both of the type III secretion systems encoded by Salmonella Pathogenicity Islands 1 and 2 showed no virulence defect. In contrast, we observed reduced pathogenic potential of a phoQ mutant indicating an important role for the PhoPQ two-component signal transduction system. Lipopolysaccharide (LPS structure was also shown to influence Salmonella virulence in G. mellonella. A waaL(rfaL mutant, which lacks the entire O-antigen (OAg, was virtually avirulent, while a wzz(ST/wzz(fepE double mutant expressing only a very short OAg was highly attenuated for virulence. Furthermore, shortly after infection both LPS mutant strains showed decreased replication when compared to the wild type in a flow cytometry-based competitive index assay. In this study we successfully established a G. mellonella model of S. Typhimurium infection. By identifying PhoQ and LPS OAg length as key determinants of virulence in the wax moth larvae we proved that there is an overlap between this and other animal model systems, thus confirming that the G. mellonella infection model is suitable for assessing aspects of Salmonella virulence function.

  10. Control of Salmonella enterica serovar Enteritidis in laying hens by inactivated Salmonella Enteritidis vaccines "Controle de Salmonella enterica sorovar Enteritidis em poedeiras comerciais com a utilização de vacinas inativadas"

    Directory of Open Access Journals (Sweden)

    Oliveiro Caetano de Freitas Neto

    2008-06-01

    Full Text Available Salmonella Enteritidis is one of the agents that is responsible for outbreaks of human foodborne salmonellosis caused by Salmonella Enteritidis and is generally associated with the consumption of poultry products. Inactivated Salmonella Enteritidis cell vaccine is one of the available methods to control Salmonella Enteritidis in breeders and laying hens, however results in terms of efficacy vary. This vaccine has never been tested in Brazil, therefore, the present work was carried out to assess three commercial inactivated Salmonella Enteritidis vaccines allowed in Brazil. Four hundred white light variety commercial laying hens were obtained at one-day-of age. At eight weeks old, the birds were divided into four groups with one hundred animals each. Birds from three groups (V1, V2 and V3 received different intramuscular vaccines, followed by a booster dose at 16 weeks of age. Birds from another group (CG were not vaccinated. When the laying hens were 20, 25 and 31 weeks old, 13 from each group were transferred to another room and were challenged by inoculating 2 mL neat culture of Salmonella Enteritidis. On the second day after each challenge, the caecal contents, spleen, liver and ovary of three birds from each group were analyzed for the presence of Salmonella Enteritidis. Twice a week a cloacal swab of each bird was taken and all eggs laid were examined for the presence of Salmonella Enteritidis. After four consecutive negative cloacal swabs in all the groups, the birds were sacrificed so as to examine the liver, caecal contents and ovaries. Overall, the inactivated vaccine used in group V3 reduced Salmonella Enteritidis in the feces and eggs. A very small amount of Salmonella was found in the spleen, liver, ovary and caeca of the birds in the four groups during the whole experiment. In general, inactivated Salmonella Enteritidis vaccines was able to decrease the presence of Salmonella Enteritidis in the birds and in the eggs as well

  11. Attenuated Salmonella enterica serovar Typhi and Shigella flexneri 2a strains mucosally deliver DNA vaccines encoding measles virus hemagglutinin, inducing specific immune responses and protection in cotton rats.

    Science.gov (United States)

    Pasetti, Marcela F; Barry, Eileen M; Losonsky, Genevieve; Singh, Mahender; Medina-Moreno, Sandra M; Polo, John M; Ulmer, Jeffrey; Robinson, Harriet; Sztein, Marcelo B; Levine, Myron M

    2003-05-01

    Measles remains a leading cause of child mortality in developing countries. Residual maternal measles antibodies and immunologic immaturity dampen immunogenicity of the current vaccine in young infants. Because cotton rat respiratory tract is susceptible to measles virus (MV) replication after intranasal (i.n.) challenge, this model can be used to assess the efficacy of MV vaccines. Pursuing a new measles vaccine strategy that might be effective in young infants, we used attenuated Salmonella enterica serovar Typhi CVD 908-htrA and Shigella flexneri 2a CVD 1208 vaccines to deliver mucosally to cotton rats eukaryotic expression plasmid pGA3-mH and Sindbis virus-based DNA replicon pMSIN-H encoding MV hemagglutinin (H). The initial i.n. dose-response with bacterial vectors alone identified a well-tolerated dosage (1 x 10(9) to 7 x 10(9) CFU) and a volume (20 micro l) that elicited strong antivector immune responses. Animals immunized i.n. on days 0, 28, and 76 with bacterial vectors carrying DNA plasmids encoding MV H or immunized parenterally with these naked DNA vaccine plasmids developed MV plaque reduction neutralizing antibodies and proliferative responses against MV antigens. In a subsequent experiment of identical design, cotton rats were challenged with wild-type MV 1 month after the third dose of vaccine or placebo. MV titers were significantly reduced in lung tissue of animals immunized with MV DNA vaccines delivered either via bacterial live vectors or parenterally. Since attenuated serovar Typhi and S. flexneri can deliver measles DNA vaccines mucosally in cotton rats, inducing measles immune responses (including neutralizing antibodies) and protection, boosting strategies can now be evaluated in animals primed with MV DNA vaccines.

  12. Cellulitis Due to Salmonella infantis.

    Directory of Open Access Journals (Sweden)

    Satish R Patil

    2013-01-01

    Full Text Available Bacteria of the genus Salmonella are highly adapted for the growth in both humans and animals and cause a wide spectrum of disease. The growth of Serotypes S. typhi and S. paratyphi is restricted to human hosts, in whom these organisms cause enteric (typhoid fever. The remaining Serotypes (non typhoidal Salmonella or NTS can colonize the gastrointestinal tracts of the broad range of animals, including mammals, reptiles, birds and insects. The usual clinical presentation of non-typhoidal salmonellae (NTS infection is self limited gastroenteritis; however bacteremia and focal extra intestinal infection may occur. However salmonella localization to the skin presenting as cutaneous ulceration is regarded as a rare event. Rates of morbidity and mortality associated with NTS are highest among the elderly, infants, and immunocompromised individuals, including those with hemoglobinopathies, HIV infection, or infections that cause blockade of the reticuloendothelial system. We isolated S.infantis in 50 years old man with left leg cellulitis. The serotype was confirmed at Central Research Institute, Kasauli.

  13. Rapid radiometric method for detection of Salmonella in foods

    International Nuclear Information System (INIS)

    Stewart, B.J.; Eyles, M.J.; Murrell, W.G.

    1980-01-01

    A radiometric method for the detection of Salmonella in foods has been developed which is based on Salmonella poly H agglutinating serum preventing Salmonella from producing 14CO2 from [14C] dulcitol. The method will detect the presence or absence of Salmonella in a product within 30 h compared to 4 to 5 days by routine culture methods. The method has been evaluated against a routine culture method using 58 samples of food. The overall agreement was 91%. Five samples negative for Salmonella by the routine method were positive by the radiometric method. These may have been false positives. However, the routine method may have failed to detect Salmonella due to the presence of large numbers of lactose-fermenting bacteria which hindered isolation of Salmonella colonies on the selective agar plates

  14. Acidic pH and divalent cation sensing by PhoQ are dispensable for systemic salmonellae virulence.

    Science.gov (United States)

    Hicks, Kevin G; Delbecq, Scott P; Sancho-Vaello, Enea; Blanc, Marie-Pierre; Dove, Katja K; Prost, Lynne R; Daley, Margaret E; Zeth, Kornelius; Klevit, Rachel E; Miller, Samuel I

    2015-05-23

    Salmonella PhoQ is a histidine kinase with a periplasmic sensor domain (PD) that promotes virulence by detecting the macrophage phagosome. PhoQ activity is repressed by divalent cations and induced in environments of acidic pH, limited divalent cations, and cationic antimicrobial peptides (CAMP). Previously, it was unclear which signals are sensed by salmonellae to promote PhoQ-mediated virulence. We defined conformational changes produced in the PhoQ PD on exposure to acidic pH that indicate structural flexibility is induced in α-helices 4 and 5, suggesting this region contributes to pH sensing. Therefore, we engineered a disulfide bond between W104C and A128C in the PhoQ PD that restrains conformational flexibility in α-helices 4 and 5. PhoQ(W104C-A128C) is responsive to CAMP, but is inhibited for activation by acidic pH and divalent cation limitation. phoQ(W104C-A128C) Salmonella enterica Typhimurium is virulent in mice, indicating that acidic pH and divalent cation sensing by PhoQ are dispensable for virulence.

  15. Salmonella capture using orbiting magnetic microbeads

    Science.gov (United States)

    Owen, Drew; Ballard, Matthew; Mills, Zachary; Hanasoge, Srinivas; Hesketh, Peter; Alexeev, Alexander

    2014-11-01

    Using three-dimensional simulations and experiments, we examine capture of salmonella from a complex fluid sample flowing through a microfluidic channel. Capture is performed using orbiting magnetic microbeads, which can easily be extracted from the system for analysis after salmonella capture. Numerical simulations are used to model the dynamics of the system, which consists of a microchannel filled with a viscous fluid, model salmonella, magnetic microbeads and a series of angled parallel ridges lining the top of the microchannel. Simulations provide a statistical measure of the ability of the system to capture target salmonella. Our modeling findings guide the design of a lab-on-a-chip experimental device to be used for the detection of salmonella from complex food samples, allowing for the detection of the bacteria at the food source and preventing the consumption of contaminated food. Such a device can be used as a generic platform for the detection of a variety of biomaterials from complex fluids. This work is supported by a grant from the United States Department of Agriculture.

  16. Explicit hypoxia targeting with tumor suppression by creating an "obligate" anaerobic Salmonella Typhimurium strain.

    Science.gov (United States)

    Yu, Bin; Yang, Mei; Shi, Lei; Yao, Yandan; Jiang, Qinqin; Li, Xuefei; Tang, Lei-Han; Zheng, Bo-Jian; Yuen, Kwok-Yung; Smith, David K; Song, Erwei; Huang, Jian-Dong

    2012-01-01

    Using bacteria as therapeutic agents against solid tumors is emerging as an area of great potential in the treatment of cancer. Obligate and facultative anaerobic bacteria have been shown to infiltrate the hypoxic regions of solid tumors, thereby reducing their growth rate or causing regression. However, a major challenge for bacterial therapy of cancer with facultative anaerobes is avoiding damage to normal tissues. Consequently the virulence of bacteria must be adequately attenuated for therapeutic use. By placing an essential gene under a hypoxia conditioned promoter, SalmonellaTyphimurium strain SL7207 was engineered to survive only in anaerobic conditions (strain YB1) without otherwise affecting its functions. In breast tumor bearing nude mice, YB1 grew within the tumor, retarding its growth, while being rapidly eliminated from normal tissues. YB1 provides a safe bacterial vector for anti-tumor therapies without compromising the other functions or tumor fitness of the bacterium as attenuation methods normally do.

  17. Electroacupuncture improves cerebral blood flow and attenuates moderate ischemic injury via Angiotensin II its receptors-mediated mechanism in rats.

    Science.gov (United States)

    Li, Jing; He, Jiaojun; Du, Yuanhao; Cui, Jingjun; Ma, Ying; Zhang, Xuezhu

    2014-11-11

    To investigate the effects and potential mechanism of electroacupuncture intervention on expressions of Angiotensin II and its receptors-mediated signaling pathway in experimentally induced cerebral ischemia. Totally 126 male Wistar rats were randomly divided into control group, model group and EA group. The latter two were further divided into ten subgroups (n = 6) following Middle Cerebral Artery Occlusion (MCAO). Changes in regional cerebral blood flow (rCBF) and expressions of Angiotensin II and its receptors (AT1R, AT2R), as well as effector proteins in phosphatidyl inositol signal pathway were monitored before and at different times after MCAO. MCAO-induced decline of ipsilateral rCBF was partially suppressed by electroacupuncture, and contralateral blood flow was also superior to that of model group. Angiotensin II level was remarkably elevated immediately after MCAO, while electroacupuncture group exhibited significantly lower levels at 1 to 3 h and the value was significantly increased thereafter. The enhanced expression of AT1R was partially inhibited by electroacupuncture, while increased AT2R level was further induced. Electroacupuncture stimulation attenuated and postponed the upregulated-expressions of Gq and CaM these upregulations. ELISA results showed sharply increased expressions of DAG and IP3, which were remarkably neutralized by electroacupuncture. MCAO induced significant increases in expression of Angiotensin II and its receptor-mediated signal pathway. These enhanced expressions were significantly attenuated by electroacupuncture intervention, followed by reduced vasoconstriction and improved blood supply in ischemic region, and ultimately conferred beneficial effects on cerebral ischemia.

  18. Long-Term Live Cell Imaging Reveals New Roles For Salmonella Effector Proteins SseG and SteA

    Science.gov (United States)

    McQuate, Sarah E.; Young, Alexandra M.; Silva-Herzog, Eugenia; Bunker, Eric; Hernandez, Mateo; de Chaumont, Fabrice; Liu, Xuedong; Detweiler, Corrella S.; Palmer, Amy E.

    2016-01-01

    Summary Salmonella Typhimurium is an intracellular bacterial pathogen that infects both epithelial cells and macrophages. Salmonella effector proteins, which are translocated into the host cell and manipulate host cell components, control the ability to replicate and/or survive in host cells. Due to the complexity and heterogeneity of Salmonella infections, there is growing recognition of the need for single cell and live-cell imaging approaches to identify and characterize the diversity of cellular phenotypes and how they evolve over time. Here we establish a pipeline for long-term (16 hours) live-cell imaging of infected cells and subsequent image analysis methods. We apply this pipeline to track bacterial replication within the Salmonella-containing vacuole in epithelial cells, quantify vacuolar replication versus survival in macrophages, and investigate the role of individual effector proteins in mediating these parameters. This approach revealed that dispersed bacteria can coalesce at later stages of infection, that the effector protein SseG influences the propensity for cytosolic hyperreplication in epithelial cells, and that while SteA only has a subtle effect on vacuolar replication in epithelial cells, it has a profound impact on infection parameters in immunocompetent macrophages, suggesting differential roles for effector proteins in different infection models. PMID:27376507

  19. Bacteriological detection of Salmonella in the presence of competitive micro-organisms (A collaborative study amongst the National Reference Laboratories for Salmonella)

    NARCIS (Netherlands)

    Voogt N; Veld PH in ' t; Nagelkerke N; Henken AM; MGB

    1997-01-01

    Het Communautair Referentie Laboratorium voor Salmonella heeft een tweede bacteriologisch ringonderzoek georganiseerd met deelname van de Nationale Referentie Laboratoria voor Salmonella. Het belangrijkste doel van dit onderzoek was verschillen tussen de NRLs in de resultaten van Salmonella

  20. Bactericidal Immunity to Salmonella in Africans and Mechanisms Causing Its Failure in HIV Infection.

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    Yun Shan Goh

    2016-04-01

    Full Text Available Nontyphoidal strains of Salmonella are a leading cause of death among HIV-infected Africans. Antibody-induced complement-mediated killing protects healthy Africans against Salmonella, but increased levels of anti-lipopolysaccharide (LPS antibodies in some HIV-infected African adults block this killing. The objective was to understand how these high levels of anti-LPS antibodies interfere with the killing of Salmonella.Sera and affinity-purified antibodies from African HIV-infected adults that failed to kill invasive S. Typhimurium D23580 were compared to sera from HIV-uninfected and HIV-infected subjects with bactericidal activity. The failure of sera from certain HIV-infected subjects to kill Salmonella was found to be due to an inherent inhibitory effect of anti-LPS antibodies. This inhibition was concentration-dependent and strongly associated with IgA and IgG2 anti-LPS antibodies (p<0.0001 for both. IgG anti-LPS antibodies, from sera of HIV-infected individuals that inhibit killing at high concentration, induced killing when diluted. Conversely, IgG, from sera of HIV-uninfected adults that induce killing, inhibited killing when concentrated. IgM anti-LPS antibodies from all subjects also induced Salmonella killing. Finally, the inhibitory effect of high concentrations of anti-LPS antibodies is seen with IgM as well as IgG and IgA. No correlation was found between affinity or avidity, or complement deposition or consumption, and inhibition of killing.IgG and IgM classes of anti-S. Typhimurium LPS antibodies from HIV-infected and HIV-uninfected individuals are bactericidal, while at very high concentrations, anti-LPS antibodies of all classes inhibit in vitro killing of Salmonella. This could be due to a variety of mechanisms relating to the poor ability of IgA and IgG2 to activate complement, and deposition of complement at sites where it cannot insert in the bacterial membrane. Vaccine trials are required to understand the significance of

  1. Aptamer-based impedimetric sensor for bacterial typing.

    Science.gov (United States)

    Labib, Mahmoud; Zamay, Anna S; Kolovskaya, Olga S; Reshetneva, Irina T; Zamay, Galina S; Kibbee, Richard J; Sattar, Syed A; Zamay, Tatiana N; Berezovski, Maxim V

    2012-10-02

    The development of an aptamer-based impedimetric sensor for typing of bacteria (AIST-B) is presented. Highly specific DNA aptamers to Salmonella enteritidis were selected via Cell-SELEX technique. Twelve rounds of selection were performed; each comprises a positive selection step against S. enteritidis and a negative selection step against a mixture of related pathogens, including Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Citrobacter freundii, to ensure the species-specificity of the selected aptamers. After sequencing of the pool showing the highest binding affinity to S. enteritidis, a DNA sequence of high affinity to the bacteria was integrated into an impedimetric sensor via self-assembly onto a gold nanoparticles-modified screen-printed carbon electrode (GNPs-SPCE). Remarkably, this aptasensor is highly selective and can successfully detect S. enteritidis down to 600 CFU mL(-1) (equivalent to 18 CFU in 30 μL assay volume) in 10 min and distinguish it from other Salmonella species, including S. typhimurium and S. choleraesuis. This report is envisaged to open a new venue for the aptamer-based typing of a variety of microorganisms using a rapid, economic, and label-free electrochemical platform.

  2. Sources of salmonellae in an uninfected commercially-processed broiler flock.

    Science.gov (United States)

    Rigby, C E; Pettit, J R; Baker, M F; Bentley, A H; Salomons, M O; Lior, H

    1980-07-01

    Cultural monitoring was used to study the incidence and sources of salmonellae in a 4160 bird broiler flock during the growing period, transport and processing in a commercial plant. No salmonellae were isolated from any of 132 litter samples of 189 chickens cultured during the seven-week growing period, even though nest litter samples from four of the eight parent flocks yielded salmonellae and Salmonella worthington was isolated from the meat meal component of the grower ration. On arrival at the plant, 2/23 birds sampled carried S. infantis on their feathers, although intestinal cultures failed to yield salmonellae. Three of 18 processed carcasses samples yielded salmonellae (S. infantis, S. heidelberg, S. typhimurium var copenhagen). The most likely source of these salmonellae was the plastic transport crates, since 15/107 sampled before the birds were loaded yielded salmonellae (S. infantis, S. typhimurium). The crate washer at the plant did not reduce the incidence of Salmonella-contaminated crates, since 16/116 sampled after washing yielded salmonellae (S. infantis, S. typhimurium, S. heidelberg, S. schwarzengrund, S. albany).

  3. Construction of genetic markers for the study of Salmonella typhimurium infection of murine macrophages

    DEFF Research Database (Denmark)

    Jelsbak, Lotte; Olsen, John Elmerdahl

    in combination with available host markers it will be possible to estimate the time-point at which a specific gene is required for progression of SCV maturation. These developmentally regulated reporter fusions constitute a set of novel developmental markers for the study of Salmonella Typhimurium infection...... with the host cell, (2) Formation of early SCV, (3) Maturation into late SCV, (4) Initiation of bacterial replication, (5) Formation of Sifs. In this project, we have constructed a set of reporter fusions which are temporally and spatially regulated during the progression of SCV maturation. The reporter fusions...... were constructed using Red-mediated recombination (1) and the promoters were selected from the recently published expressional data of Salmonella infection of murine macrophages (2). As reporter proteins we both use a stable GFPmut3 variant as well as an unstable GFP variant (3). Using these fusions...

  4. Analysis of pools of targeted Salmonella deletion mutants identifies novel genes affecting fitness during competitive infection in mice.

    Directory of Open Access Journals (Sweden)

    Carlos A Santiviago

    2009-07-01

    Full Text Available Pools of mutants of minimal complexity but maximal coverage of genes of interest facilitate screening for genes under selection in a particular environment. We constructed individual deletion mutants in 1,023 Salmonella enterica serovar Typhimurium genes, including almost all genes found in Salmonella but not in related genera. All mutations were confirmed simultaneously using a novel amplification strategy to produce labeled RNA from a T7 RNA polymerase promoter, introduced during the construction of each mutant, followed by hybridization of this labeled RNA to a Typhimurium genome tiling array. To demonstrate the ability to identify fitness phenotypes using our pool of mutants, the pool was subjected to selection by intraperitoneal injection into BALB/c mice and subsequent recovery from spleens. Changes in the representation of each mutant were monitored using T7 transcripts hybridized to a novel inexpensive minimal microarray. Among the top 120 statistically significant spleen colonization phenotypes, more than 40 were mutations in genes with no previously known role in this model. Fifteen phenotypes were tested using individual mutants in competitive assays of intraperitoneal infection in mice and eleven were confirmed, including the first two examples of attenuation for sRNA mutants in Salmonella. We refer to the method as Array-based analysis of cistrons under selection (ABACUS.

  5. Survival of Salmonella during baking of peanut butter cookies.

    Science.gov (United States)

    Lathrop, Amanda A; Taylor, Tiffany; Schnepf, James

    2014-04-01

    Peanuts and peanut-based products have been the source of recent Salmonella outbreaks worldwide. Because peanut butter is commonly used as an ingredient in baked goods, such as cookies, the potential risk of Salmonella remaining in these products after baking needs to be assessed. This research examines the potential hazard of Salmonella in peanut butter cookies when it is introduced via the peanut-derived ingredient. The survival of Salmonella during the baking of peanut butter cookies was determined. Commercial, creamy-style peanut butter was artificially inoculated with a five-strain Salmonella cocktail at a target concentration of 10(8) CFU/g. The inoculated peanut butter was then used to prepare peanut butter cookie dough following a standard recipe. Cookies were baked at 350 °F (177 °C) and were sampled after 10, 11, 12, 13, 14, and 15 min. Temperature profiles of the oven and cookies were monitored during baking. The water activity and pH of the inoculated and uninoculated peanut butter, raw dough, and baked cookies were measured. Immediately after baking, cookies were cooled, and the survival of Salmonella was determined by direct plating or enrichment. After baking cookies for 10 min, the minimum reduction of Salmonella observed was 4.8 log. In cookies baked for 13 and 14 min, Salmonella was only detectable by enrichment reflecting a Salmonella reduction in the range of 5.2 to 6.2 log. Cookies baked for 15 min had no detectable Salmonella. Results of this study showed that proper baking will reduce Salmonella in peanut butter cookies by 5 log or more.

  6. Altered IFN-γ-mediated immunity and transcriptional expression patterns in N-Ethyl-N-nitrosourea-induced STAT4 mutants confer susceptibility to acute typhoid-like disease.

    Science.gov (United States)

    Eva, Megan M; Yuki, Kyoko E; Dauphinee, Shauna M; Schwartzentruber, Jeremy A; Pyzik, Michal; Paquet, Marilène; Lathrop, Mark; Majewski, Jacek; Vidal, Silvia M; Malo, Danielle

    2014-01-01

    Salmonella enterica is a ubiquitous Gram-negative intracellular bacterium that continues to pose a global challenge to human health. The etiology of Salmonella pathogenesis is complex and controlled by pathogen, environmental, and host genetic factors. In fact, patients immunodeficient in genes in the IL-12, IL-23/IFN-γ pathway are predisposed to invasive nontyphoidal Salmonella infection. Using a forward genomics approach by N-ethyl-N-nitrosourea (ENU) germline mutagenesis in mice, we identified the Ity14 (Immunity to Typhimurium locus 14) pedigree exhibiting increased susceptibility following in vivo Salmonella challenge. A DNA-binding domain mutation (p.G418_E445) in Stat4 (Signal Transducer and Activator of Transcription Factor 4) was the causative mutation. STAT4 signals downstream of IL-12 to mediate transcriptional regulation of inflammatory immune responses. In mutant Ity14 mice, the increased splenic and hepatic bacterial load resulted from an intrinsic defect in innate cell function, IFN-γ-mediated immunity, and disorganized granuloma formation. We further show that NK and NKT cells play an important role in mediating control of Salmonella in Stat4(Ity14/Ity14) mice. Stat4(Ity14/Ity14) mice had increased expression of genes involved in cell-cell interactions and communication, as well as increased CD11b expression on a subset of splenic myeloid dendritic cells, resulting in compromised recruitment of inflammatory cells to the spleen during Salmonella infection. Stat4(Ity14/Ity14) presented upregulated compensatory mechanisms, although inefficient and ultimately Stat4(Ity14/Ity14) mice develop fatal bacteremia. The following study further elucidates the pathophysiological impact of STAT4 during Salmonella infection.

  7. Conservation of Salmonella infection mechanisms in plants and animals.

    Directory of Open Access Journals (Sweden)

    Adam Schikora

    Full Text Available Salmonella virulence in animals depends on effectors injected by Type III Secretion Systems (T3SSs. In this report we demonstrate that Salmonella mutants that are unable to deliver effectors are also compromised in infection of Arabidopsis thaliana plants. Transcriptome analysis revealed that in contrast to wild type bacteria, T3SS mutants of Salmonella are compromised in suppressing highly conserved Arabidopsis genes that play a prominent role during Salmonella infection of animals. We also found that Salmonella originating from infected plants are equally virulent for human cells and mice. These results indicate a high degree of conservation in the defense and infection mechanism of animal and plant hosts during Salmonella infection.

  8. The Development and Evaluation of a Loop-Mediated Isothermal Amplification Method for the Rapid Detection of Salmonella enterica serovar Typhi.

    Directory of Open Access Journals (Sweden)

    Fenxia Fan

    Full Text Available Typhoid fever remains a public health threat in many countries. A positive result in traditional culture is a gold-standard for typhoid diagnosis, but this method is time consuming and not sensitive enough for detection of samples containing a low copy number of the target organism. The availability of the loop-mediated isothermal amplification (LAMP assay, which offers high speed and simplicity in detection of specific targets, has vastly improved the diagnosis of numerous infectious diseases. However, little research efforts have been made on utilizing this approach for diagnosis of Salmonella enterica serovar Typhi by targeting a single and specific gene. In this study, a LAMP assay for rapid detection of S. Typhi based on a novel marker gene, termed STY2879-LAMP, was established and evaluated with real-time PCR (RT-PCR. The specificity tests showed that STY2879 could be amplified in all S. Typhi strains isolated in different years and regions in China, whereas no amplification was observable in non-typhoidal strains covering 34 Salmonella serotypes and other pathogens causing febrile illness. The detection limit of STY2879-LAMP for S. Typhi was 15 copies/reaction in reference plasmids, 200 CFU/g with simple heat-treatment of DNA extracted from simulated stool samples and 20 CFU/ml with DNA extracted from simulated blood samples, which was 10 fold more sensitive than the parallel RT-PCR control experiment. Furthermore, the sensitivity of STY2879-LAMP and RT-PCR combining the traditional culture enrichment method for simulated stool and blood spiked with lower S. Typhi count during the 10 h enrichment time was also determined. In comparison with LAMP, the positive reaction time for RT-PCR required additional 2-3 h enrichment time for either simulated stool or blood specimens. Therefore, STY2879-LAMP is of practical value in the clinical settings and has a good potential for application in developing regions due to its easy-to-use protocol.

  9. Antibiotic resistance, integrons and Salmonella genomic island 1 among non-typhoidal Salmonella serovars in The Netherlands.

    NARCIS (Netherlands)

    Vo, An T T; Duijkeren, Engeline van; Fluit, Ad C; Wannet, Wim J B; Verbruggen, Anjo J; Maas, Henny M E; Gaastra, Wim

    2006-01-01

    The objective of this study was to investigate the antimicrobial resistance patterns, integron characteristics and gene cassettes as well as the presence of Salmonella genomic island 1 (SGI1) in non-typhoidal Salmonella (NTS) isolates from human and animal origin. Epidemiologically unrelated Dutch

  10. Curcumin increases the pathogenicity of Salmonella enterica serovar Typhimurium in murine model.

    Directory of Open Access Journals (Sweden)

    Sandhya A Marathe

    Full Text Available Curcumin has gained immense importance for its vast therapeutic and prophylactic applications. Contrary to this, our study reveals that it regulates the defense pathways of Salmonella enterica serovar Typhimurium (S. Typhimurium to enhance its pathogenicity. In a murine model of typhoid fever, we observed higher bacterial load in Peyer's patches, mesenteric lymph node, spleen and liver, when infected with curcumin-treated Salmonella. Curcumin increased the resistance of S. Typhimurium against antimicrobial agents like antimicrobial peptides, reactive oxygen and nitrogen species. This increased tolerance might be attributed to the up-regulation of genes involved in resistance against antimicrobial peptides--pmrD and pmrHFIJKLM and genes with antioxidant function--mntH, sodA and sitA. We implicate that iron chelation property of curcumin have a role in regulating mntH and sitA. Interestingly, we see that the curcumin-mediated modulation of pmr genes is through the PhoPQ regulatory system. Curcumin downregulates SPI1 genes, required for entry into epithelial cells and upregulates SPI2 genes required to intracellular survival. Since it is known that the SPI1 and SPI2 system can be regulated by the PhoPQ system, this common regulator could explain curcumin's mode of action. This data urges us to rethink the indiscriminate use of curcumin especially during Salmonella outbreaks.

  11. Swimming attenuates d-galactose-induced brain aging via suppressing miR-34a-mediated autophagy impairment and abnormal mitochondrial dynamics.

    Science.gov (United States)

    Kou, Xianjuan; Li, Jie; Liu, Xingran; Chang, Jingru; Zhao, Qingxia; Jia, Shaohui; Fan, Jingjing; Chen, Ning

    2017-06-01

    microRNAs (miRNAs) have been reported to be involved in many neurodegenerative diseases. To explore the regulatory role of miR-34a in aging-related diseases such as Alzheimer's disease (AD) during exercise intervention, we constructed a rat model with d-galactose (d-gal)-induced oxidative stress and cognitive impairment coupled with dysfunctional autophagy and abnormal mitochondrial dynamics, determined the mitigation of cognitive impairment of d-gal-induced aging rats during swimming intervention, and evaluated miR-34a-mediated functional status of autophagy and abnormal mitochondrial dynamics. Meanwhile, whether the upregulation of miR-34a can lead to dysfunctional autophagy and abnormal mitochondrial dynamics was confirmed in human SH-SY5Y cells with silenced miR-34a by the transfection of a miR-34a inhibitor. Results indicated that swimming intervention could significantly attenuate cognitive impairment, prevent the upregulation of miR-34a, mitigate the dysfunctional autophagy, and inhibit the increase of dynamin-related protein 1 (DRP1) in d-gal-induced aging model rats. In contrast, the miR-34a inhibitor in cell model not only attenuated D-gal-induced the impairment of autophagy but also decreased the expression of DRP1 and mitofusin 2 (MFN2). Therefore, swimming training can delay brain aging of d-gal-induced aging rats through attenuating the impairment of miR-34a-mediated autophagy and abnormal mitochondrial dynamics, and miR-34a could be the novel therapeutic target for aging-related diseases such as AD. NEW & NOTEWORTHY In the present study, we have found that the upregulation of miR-34a is the hallmark of aging or aging-related diseases, which can result in dysfunctional autophagy and abnormal mitochondrial dynamics. In contrast, swimming intervention can delay the aging process by rescuing the impaired functional status of autophagy and abnormal mitochondrial dynamics via the suppression of miR-34a. Copyright © 2017 the American Physiological Society.

  12. Incidence of Salmonella contamination in broiler chickens in Saskatchewan.

    Science.gov (United States)

    Bhargava, K K; O'Neil, J B; Prior, M G; Dunkelgod, K E

    1983-01-01

    The incidence of Salmonella contamination in ten Saskatchewan broiler flocks varying in size from 6 200 to 14 000 was investigated from February, 1977 to April, 1979. Prior to the initial chick placement, brooding equipment, feed, water and fresh litter samples were found to be free of Salmonellae. Samples obtained from the clean and disinfected processing plant equipment before the commencement of daily operation were negative except the isolation for Salmonella anatum from the fingers of the defeathering machine in flock 4. There was no evidence of Salmonella contamination in flocks 5, 6, 8 and 10. The incidence of Salmonella was lower when cloacal swabs were taken from day old chicks fasted for 48 hours than for the same groups of chicks when carcasses were blended in nutrient broth (flocks 7 and 9). The blending of such chicks appears to be a more critical test. The serotypes isolated from eviscerated birds were the same as those isolated from used litter samples. Salmonella saintpaul was isolated from a water sample at 53 days in flock 1 and the same serotype was recovered from the intestinal contents and skin of eviscerated birds. Salmonella typhimurium was recovered from the eviscerated birds and neck samples in flock 3. In flock 4, S. saintpaul and S. anatum were isolated from 13% of the eviscerated birds sampled. Salmonella thompson, Salmonella agona and Salmonella heidelberg were recovered from 61%, 5% and 1%, respectively, of the processed carcasses sampled in flock 7.

  13. Salmonella serovar spectrum associated with reptiles in Poland

    Directory of Open Access Journals (Sweden)

    Tomasz Piasecki

    2014-01-01

    Full Text Available This study aimed to evaluate the incidence of Salmonella isolates from a wide variety of reptiles in Poland. A total of 374 faecal samples from chelonians, lizards and snakes were collected between 2009 and 2012. The nested, two-step PCR and multiplex PCR were performed to access the incidence and to characterize Salmonella isolates. Salmonella strains were found in 122 of 374 samples (32.6%. Among the different reptilian species, Salmonella strains were found in 58 samples from lizards (38.9%, 31 samples from snakes (28.7% and 33 samples from chelonians (28.2%. Of the total of 122 strains, 72 belonged to the species Salmonella enterica subsp. enterica, 20 to the species S. enterica subs. salamae or S. enterica subs. houtanae. The incidence of S. enterica subs. diarizonae and S. enterica subs. indica was low, constituting less than 3.5% of the examined population. The findings show that reptiles can be considered as a reservoir for Salmonella and hence could pose a zoonotic hazard. In addition, multiplex PCR assay is a rapid, specific and easy-to-perform method and might be applied for rapid screening of large numbers of Salmonella samples.

  14. Salmonella Typhimurium infection in the porcine intestine

    DEFF Research Database (Denmark)

    Schauser, Kirsten; Olsen, John Elmerdahl; Larsson, Lars-Inge

    2005-01-01

    The normal intestinal epithelium is renewed with a turnover rate of 3-5 days. During Salmonella infection increased cell loss is observed, possibly as a result of programmed cell death (PCD). We have, therefore, studied the effects of Salmonella Typhimurium infection on three elements involved...... in scattered epithelial cells and the number of positive cells increased with increasing times of exposure to Salmonella (P

  15. Applications of microscopy in Salmonella research.

    Science.gov (United States)

    Malt, Layla M; Perrett, Charlotte A; Humphrey, Suzanne; Jepson, Mark A

    2015-01-01

    Salmonella enterica is a Gram-negative enteropathogen that can cause localized infections, typically resulting in gastroenteritis, or systemic infection, e.g., typhoid fever, in humans and many other animals. Understanding the mechanisms by which Salmonella induces disease has been the focus of intensive research. This has revealed that Salmonella invasion requires dynamic cross-talk between the microbe and host cells, in which bacterial adherence rapidly leads to a complex sequence of cellular responses initiated by proteins translocated into the host cell by a type 3 secretion system. Once these Salmonella-induced responses have resulted in bacterial invasion, proteins translocated by a second type 3 secretion system initiate further modulation of cellular activities to enable survival and replication of the invading pathogen. Elucidation of the complex and highly dynamic pathogen-host interactions ultimately requires analysis at the level of single cells and single infection events. To achieve this goal, researchers have applied a diverse range of microscopy techniques to analyze Salmonella infection in models ranging from whole animal to isolated cells and simple eukaryotic organisms. For example, electron microscopy and high-resolution light microscopy techniques such as confocal microscopy can reveal the precise location of Salmonella and its relationship to cellular components. Widefield light microscopy is a simpler approach with which to study the interaction of bacteria with host cells and often has advantages for live cell imaging, enabling detailed analysis of the dynamics of infection and cellular responses. Here we review the use of imaging techniques in Salmonella research and compare the capabilities of different classes of microscope to address specific types of research question. We also provide protocols and notes on some microscopy techniques used routinely in our own research.

  16. Reorganization of the Endosomal System in Salmonella-Infected Cells: The Ultrastructure of Salmonella-Induced Tubular Compartments

    Science.gov (United States)

    Krieger, Viktoria; Liebl, David; Zhang, Yuying; Rajashekar, Roopa; Chlanda, Petr; Giesker, Katrin; Chikkaballi, Deepak; Hensel, Michael

    2014-01-01

    During the intracellular life of Salmonella enterica, a unique membrane-bound compartment termed Salmonella-containing vacuole, or SCV, is formed. By means of translocated effector proteins, intracellular Salmonella also induce the formation of extensive, highly dynamic membrane tubules termed Salmonella-induced filaments or SIF. Here we report the first detailed ultrastructural analyses of the SCV and SIF by electron microscopy (EM), EM tomography and live cell correlative light and electron microscopy (CLEM). We found that a subset of SIF is composed of double membranes that enclose portions of host cell cytosol and cytoskeletal filaments within its inner lumen. Despite some morphological similarities, we found that the formation of SIF double membranes is independent from autophagy and requires the function of the effector proteins SseF and SseG. The lumen of SIF network is accessible to various types of endocytosed material and our CLEM analysis of double membrane SIF demonstrated that fluid phase markers accumulate only between the inner and outer membrane of these structures, a space continual with endosomal lumen. Our work reveals how manipulation of the endosomal membrane system by an intracellular pathogen results in a unique tubular membrane compartmentalization of the host cell, generating a shielded niche permissive for intracellular proliferation of Salmonella. PMID:25254663

  17. Salmonella spp. on chicken carcasses in processing plants in Poland.

    Science.gov (United States)

    Mikołajczyk, Anita; Radkowski, Mieczysław

    2002-09-01

    Chickens at selected points in the slaughter process and after slaughter on the dressing line in poultry plants were sampled and analyzed for Salmonella. These chickens came from the northeast part of Poland. The examinations were carried out in quarters I, II, III, and IV of 1999. All the birds were determined to be healthy by a veterinary inspection. Swab samples were taken from the cloaca after stunning and from the skin surface and body cavity of the whole bird after evisceration, after rinsing at the final rinse station but before chilling in the spin-chiller, and after cooling in the continuous cooling plant at the end of the production day. In 1999, 400 whole chickens were examined. The percentage of these 400 chickens from which Salmonella spp. were isolated was relatively high (23.75%; Salmonella-positive results were observed in 95 cases). Salmonella spp. were found after stunning in 6% of the chickens (6 of 100 samples), after evisceration in 24% (24 of 100), before cooling in 52% (52 of 100), and after cooling in 13% (13 of 100). These results show that Salmonella spp. were found more often at some processing points than at others. The lowest Salmonella spp. contamination rate (6%) for slaughter birds was found after stunning, and the highest contamination rate was found before chilling (52%). The serological types of Salmonella spp. isolated from whole chickens were Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Saintpaul, Salmonella Agona, and Salmonella Infantis. The results of these investigations indicate that Salmonella Enteritidis is the dominant serological type in infections of slaughter chickens, as it is in many countries.

  18. 9 CFR 113.30 - Detection of Salmonella contamination.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of Salmonella contamination... REQUIREMENTS Standard Procedures § 113.30 Detection of Salmonella contamination. The test for detection of Salmonella contamination provided in this section shall be conducted when such a test is prescribed in an...

  19. Characterization of a multidrug resistant Salmonella enterica give ...

    African Journals Online (AJOL)

    Salmonella enterica Give is one of the serotypes that have been incriminated in Salmonella infections; sometimes associated with hospitalization and mortalities in humans and animals in some parts of the world. In this work, we characterized one Salmonella Give isolated from cloaca swab of an Agama agama lizard ...

  20. Interactions of Salmonella with animals and plants.

    Science.gov (United States)

    Wiedemann, Agnès; Virlogeux-Payant, Isabelle; Chaussé, Anne-Marie; Schikora, Adam; Velge, Philippe

    2014-01-01

    Salmonella enterica species are Gram-negative bacteria, which are responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruits with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i) attachment to host surfaces; (ii) entry processes; (iii) multiplication; (iv) suppression of host defense mechanisms; and to point out similarities and differences between animal and plant infections.

  1. Interactions of Salmonella with animals and plants

    Directory of Open Access Journals (Sweden)

    Agnès eWiedemann

    2015-01-01

    Full Text Available Salmonella enterica species is a Gram negative bacterium, which is responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruit with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i attachment to host surfaces; (ii entry processes; (iii, multiplication; (iv suppression of host defence mechanisms ; and to point out similarities and differences between animal and plant infections.

  2. Interactions of Salmonella with animals and plants

    Science.gov (United States)

    Wiedemann, Agnès; Virlogeux-Payant, Isabelle; Chaussé, Anne-Marie; Schikora, Adam; Velge, Philippe

    2015-01-01

    Salmonella enterica species are Gram-negative bacteria, which are responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruits with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i) attachment to host surfaces; (ii) entry processes; (iii) multiplication; (iv) suppression of host defense mechanisms; and to point out similarities and differences between animal and plant infections. PMID:25653644

  3. Salmonella in beef and produce from honduras.

    Science.gov (United States)

    Maradiaga, Martha; Miller, Mark F; Thompson, Leslie; Pond, Ansen; Gragg, Sara E; Echeverry, Alejandro; Garcia, Lyda G; Loneragan, Guy H; Brashears, Mindy M

    2015-03-01

    Salmonella continues to cause a considerable number of foodborne illnesses worldwide. The sources of outbreaks include contaminated meat and produce. The purpose of this study was to establish an initial investigation of the burden of Salmonella in produce and beef from Honduras by sampling retail markets and abattoirs. Retail produce samples (cantaloupes, cilantro, cucumbers, leafy greens, peppers, and tomatoes; n = 573) were purchased in three major cities of Honduras, and retail whole-muscle beef (n = 555) samples were also purchased in four major cities. Additionally, both hide and beef carcass (n = 141) samples were collected from two Honduran abattoirs. Whole-muscle beef samples were obtained using a sponge hydrated with buffered peptone water, and 10 ml of the buffered peptone water rinsate of each produce sample was collected with a dry sponge and placed in a bag to be transported back to the United States. Salmonella was detected using a commercially available, closeplatform PCR system, and positive samples were subjected to culture on selective media to obtain isolates. Overall, the prevalence of Salmonella-positive samples, based on PCR detection in Honduras (n = 555) retail beef was 10.1% (95% confidence interval = 7.8, 12.9), whereas 7.8% (n = 141) of beef carcass and hides samples were positive in both beef plants. The overall Salmonella prevalence for all produce samples (n = 573) collected was 2.1% (95% confidence interval = 1.2, 3.6). The most common serotypes identified in Honduras were Salmonella Typhimurium followed by Derby. These results provide an indication of Salmonella contamination of beef and produce in Honduras. Developing a Salmonella baseline for Latin America through an initial investigation like the one presented here contributes to a broader global understanding of the potential exposure through food, thus providing insight into the needs for control strategies.

  4. The bacterial two-hybrid system uncovers the involvement of acetylation in regulating of Lrp activity in Salmonella Typhimurium

    Directory of Open Access Journals (Sweden)

    Ran Qin

    2016-11-01

    Full Text Available Nε-lysine acetylation is an abundant and important Post-translational modification in bacteria. We used the bacterial two-hybrid system to screen the genome library of the Salmonella Typhimurium to identify potential proteins involved in acetyltransferase Pat - or deacetylase CobB-mediated acetylation. Then, the in vitro (deacetylation assays were used to validate the potential targets, such as STM14_1074, NrdF, RhaR. Lrp, a leucine-responsive regulatory protein and global regulator, was shown to interact with Pat. We further demonstrate that Lrp could be acetylated by Pat and deacetylated by NAD+-dependent CobB in vitro. Specifically, the conserved lysine residue 36 (K36 in helix-turn-helix (HTH DNA-binding domain of Lrp was acetylated. Acetylation of K36 impaired the function of Lrp through altering the affinity with the target promoter. The mutation of K36 in chromosome mimicking acetylation enhanced the transcriptional level of itself and attenuated the mRNA levels of Lrp-regulated genes including fimA, which was confirmed by yeast agglutination assay. These findings demonstrate that the acetylation regulates the DNA-binding activity of Lrp, suggesting that acetylation modification of transcription factors is a conserved regulatory manner to modulate gene expression in bacteria and eukaryotes.

  5. Amoxicillin / Clavulanic Acid and Cefotaxime Resistance in Salmonella Minnesota and Salmonella Heidelberg from Broiler Chickens

    Directory of Open Access Journals (Sweden)

    Rodrigues IBBE

    2017-10-01

    Full Text Available This study investigated the resistance of various Salmonella strains to beta-lactam antibiotics. Salmonella Minnesota (36 strains and Salmonella Heidelberg (24 strains were isolated from broiler chickens and carcasses by the Disk Diffusion Test and resistance genes blaCTX-M-8, blaACC-1 and blaCMY-2 were detected by PCR. Of the 60 strains tested, 80% were resistant to at least one antibiotic. Specifically, 66.7% were resistant to amoxicillin/clavulanic acid and 75% were resistant to cefotaxime. Among the amoxicillin/clavulanic acid resistant strains, the blaCMY-2 gene was detected in 40%, blaACC-1 in 37.5% and blaCTX-M-8 in 7.5%. Among the cefotaxime resistant strains, we detected the genes blaCTX-M-8 in 13.3%, blaACC-1 in 33.3%, and blaCMY-2 in 31.1%. The presence of cefotaxime- and amoxicillin/clavulanic acid-resistant Salmonella in poultry, and the prevalence of extended spectrum betalactamases and AmpC-betalactamases in these strains are of huge concern to public health and economy.

  6. Salmonella enterica Induces And Subverts The Plant Immune System

    Directory of Open Access Journals (Sweden)

    Ana Victoria Garcia

    2014-04-01

    Full Text Available Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Whereas it was shown that plants raise defense responses against Salmonella, these bacteria persist and proliferate in various plant tissues. Recent reports shed light into the molecular interaction between plants and Salmonella, highlighting the defense pathways induced and the means used by the bacteria to escape the plant immune system and accomplish colonization. It was recently shown that plants detect Salmonella pathogen-associated molecular patterns (PAMPs, such as the flagellin peptide flg22, and activate hallmarks of the defense program known as PAMP-triggered immunity (PTI. Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS as T3SS mutants were found to induce stronger plant defense responses than wild type bacteria. Although Salmonella effector delivery into plant cells has not been shown, expression of Salmonella effectors in plant tissues shows that these bacteria also possess powerful means to manipulate the plant immune system. Altogether, the data gathered suggest that Salmonella triggers PTI in plants and evolved strategies to avoid or subvert plant immunity.

  7. Salmonella enterica induces and subverts the plant immune system

    KAUST Repository

    García, Ana V.

    2014-04-04

    Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Although it was shown that plants raise defense responses against Salmonella, these bacteria persist and proliferate in various plant tissues. Recent reports shed light into the molecular interaction between plants and Salmonella, highlighting the defense pathways induced and the means used by the bacteria to escape the plant immune system and accomplish colonization. It was recently shown that plants detect Salmonella pathogen-associated molecular patterns (PAMPs), such as the flagellin peptide flg22, and activate hallmarks of the defense program known as PAMP-triggered immunity (PTI). Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS) as T3SS mutants were found to induce stronger plant defense responses than wild type bacteria. Although Salmonella effector delivery into plant cells has not been shown, expression of Salmonella effectors in plant tissues shows that these bacteria also possess powerful means to manipulate the plant immune system. Altogether, these data suggest that Salmonella triggers PTI in plants and evolved strategies to avoid or subvert plant immunity. 2014 Garca and Hirt.

  8. Explicit hypoxia targeting with tumor suppression by creating an “obligate” anaerobic Salmonella Typhimurium strain

    Science.gov (United States)

    Yu, Bin; Yang, Mei; Shi, Lei; Yao, Yandan; Jiang, Qinqin; Li, Xuefei; Tang, Lei-Han; Zheng, Bo-Jian; Yuen, Kwok-Yung; Smith, David K.; Song, Erwei; Huang, Jian-Dong

    2012-01-01

    Using bacteria as therapeutic agents against solid tumors is emerging as an area of great potential in the treatment of cancer. Obligate and facultative anaerobic bacteria have been shown to infiltrate the hypoxic regions of solid tumors, thereby reducing their growth rate or causing regression. However, a major challenge for bacterial therapy of cancer with facultative anaerobes is avoiding damage to normal tissues. Consequently the virulence of bacteria must be adequately attenuated for therapeutic use. By placing an essential gene under a hypoxia conditioned promoter, Salmonella Typhimurium strain SL7207 was engineered to survive only in anaerobic conditions (strain YB1) without otherwise affecting its functions. In breast tumor bearing nude mice, YB1 grew within the tumor, retarding its growth, while being rapidly eliminated from normal tissues. YB1 provides a safe bacterial vector for anti-tumor therapies without compromising the other functions or tumor fitness of the bacterium as attenuation methods normally do. PMID:22666539

  9. Multiple antimicrobial resistance of Escherichia coli and Salmonella ...

    African Journals Online (AJOL)

    Presumptive isolates were subjected to antimicrobial susceptibility testing using 13 panels of antibiotics for both E. coli and Salmonella spp. Results showed that the overall isolation rate of Salmonella spp. was 12 (11.4%), broiler chickens had higher isolation rate 9 (12.0%) of Salmonella than local chickens. However, the ...

  10. Diversity of Salmonella isolates from central Florida surface waters.

    Science.gov (United States)

    McEgan, Rachel; Chandler, Jeffrey C; Goodridge, Lawrence D; Danyluk, Michelle D

    2014-11-01

    Identification of Salmonella serotypes is important for understanding the environmental diversity of the genus Salmonella. This study evaluates the diversity of Salmonella isolates recovered from 165 of 202 Central Florida surface water samples and investigates whether the serotype of the environmental Salmonella isolates can be predicted by a previously published multiplex PCR assay (S. Kim, J. G. Frye, J. Hu, P. J. Fedorka-Cray, R. Gautom, and D. S. Boyle, J. Clin. Microbiol. 44:3608-3615, 2006, http://dx.doi.org/10.1128/JCM.00701-06). Multiplex PCR was performed on 562 Salmonella isolates (as many as 36 isolates per water sample) to predict serotypes. Kauffmann-White serogrouping was used to confirm multiplex PCR pattern groupings before isolates were serotyped, analyzed by pulsed-field gel electrophoresis, and assayed for antimicrobial susceptibility. In 41.2% of the Salmonella-positive water samples, all Salmonella isolates had identical multiplex PCR patterns; in the remaining 58.8%, two or more multiplex PCR patterns were identified. Within each sample, isolates with matching multiplex PCR patterns had matching serogroups. The multiplex patterns of 495 isolates (88.1%) did not match any previously reported pattern. The remaining 68 isolates matched reported patterns but did not match the serotypes for those patterns. The use of the multiplex PCR allowed the number of isolates requiring further analysis to be reduced to 223. Thirty-three Salmonella enterica serotypes were identified; the most frequent included serotypes Muenchen, Rubislaw, Anatum, Gaminara, and IV_50:z4,z23:-. A majority (141/223) of Salmonella isolates clustered into one genotypic group. Salmonella isolates in Central Florida surface waters are serotypically, genotypically, and phenotypically (in terms of antimicrobial susceptibility) diverse. While isolates could be grouped as different or potentially the same using multiplex PCR, the multiplex PCR pattern did not predict the Salmonella

  11. Evaluation of Eight Different Cephalosporins for Detection of Cephalosporin Resistance in Salmonella enterica and Escherichia coli

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Hasman, Henrik; Veldman, K

    2010-01-01

    This study evaluates the efficacy of eight different cephalosporins for detection of cephalosporin resistance mediated by extended spectrum beta-lactamases (ESBL) and plasmidic AmpC beta-lactamases in Salmonella and Escherichia coli. A total of 138 E. coli and 86 Salmonella isolates with known beta......-resistant but cephalosporin-susceptible, 56 ESBL isolates and 19 isolates with plasmidic AmpC, as well as 10 ampC hyper-producing E. coli. The minimum inhibitory concentration distributions and zone inhibitions varied with the tested compound. Ampicillin-resistant isolates showed reduced susceptibility to the cephalosporins...... compared to ampicillin-susceptible isolates. Cefoperazone, cefquinome, and cefuroxime were not useful in detecting isolates with ESBL or plasmidic AmpC. The best substances for detection were cefotaxime, cefpodoxime, and ceftriaxone, whereas ceftazidime and ceftiofur were not as efficient. Ceftriaxone may...

  12. Web-based surveillance and global Salmonella distribution, 2000-2002

    DEFF Research Database (Denmark)

    Galanis, E.; Wong, Danilo Lo Fo; Patrick, M.E.

    2006-01-01

    Salmonellae are a common cause of foodborne disease worldwide. The World Health Organization (WHO) supports international foodborne disease surveillance through WHO Global Salm-Surv and other activities. WHO Global Salm-Surv members annually report the 15 most frequently isolated Salmonella...... serotypes to a Web-based country databank. We describe the global distribution of reported Salmonella serotypes from human and nonhuman sources from 2000 to 2002. Among human isolates, Salmonella enterica serovar Enteritidis was the most common serotype, accounting for 65% of all isolates. Among nonhuman...... professionals to explore hypotheses related to the sources and distribution of salmonellae worldwide....

  13. Inactivation of Salmonellae in Frozen Catfish by Gamma Irradiation

    International Nuclear Information System (INIS)

    Nouchpramoon, Kovit; Amsiri, Jarurat

    2003-06-01

    The effect of gamma irradiation on salmonellae viability in frozen catfish was investigated using fresh cut of catfish artificially contaminated with stationary phase cells of salmonellae, frozen at-18 οC and irradiated with does ranging from 0.0 to 2.4 kGy. The D 10 values for ten serovars of salmonellae ranged from 0.47 to 0.77 kGy. Salmonella Enteritidis was the most resistant serovars found in frozen catfish. Dosage at 2.5 kGy would be sufficient to kill 10 3 . 2 Salmonella Enteritidis that may occasionally present in frozen catfish

  14. Transcriptomic analysis of Salmonella desiccation resistance.

    Science.gov (United States)

    Li, Haiping; Bhaskara, Anuhya; Megalis, Christina; Tortorello, Mary Lou

    2012-12-01

    The survival of Salmonella in low moisture foods and processing environments remains a great challenge for the food industry and public health. To explore the mechanisms of Salmonella desiccation resistance, we studied the transcriptomic responses in Salmonella Tennessee (Tennessee), using Salmonella Typhimurium LT2 (LT2), a strain weakly resistant to desiccation, as a reference strain. In response to 2 h of air-drying at 11% equilibrated relative humidity, approximately one-fourth of the open reading frames (ORFs) in the Tennessee genome and one-fifth in LT2 were differentially expressed (>2-fold). Among all differentially expressed functional groups (>5-fold) in both strains, the expression fold change associated with fatty acid metabolism was the highest, and constituted 51% and 35% of the total expression fold change in Tennessee and LT2, respectively. Tennessee showed greater changes in expression of genes associated with stress response and envelope modification than LT2, while showing lesser changes in protein biosynthesis expression. Expression of flagella genes was significantly more inhibited in stationary phase cells of Tennessee than LT2 both before and after desiccation. The accumulation of the osmolyte trehalose was significantly induced by desiccation in Tennessee, but no increase was detectable in LT2, which is consistent with the expression patterns of the entire trehalose biosynthesis and degradation pathways in both strains. Results from this study present a global view of the dynamic desiccation responses in Salmonella, which will guide future research efforts to control Salmonella in low moisture environments.

  15. Salmonella Typhimurium transcription profiles in space flight

    Data.gov (United States)

    National Aeronautics and Space Administration — Salmonella transcription profiles were obtained from samples flown on space shuttle mission STS-115 and compared to profiles from Salmonella grown under identical...

  16. antimicrobial susceptibility pattern of Salmonella species

    African Journals Online (AJOL)

    user

    ABSTRACT. Treatment of enteric fever is increasingly becoming very challenging due to the increasing wave of antibiotic resistance. This study is a review of the contemporary antimicrobial susceptibility pattern of. Salmonella species. The antimicrobial susceptibility pattern of Salmonella species to a wide range of.

  17. EURL-Salmonella 8th interlaboratory comparison study Food 2016 : Detection of Salmonella in minced chicken meat

    NARCIS (Netherlands)

    Kuijpers AFA; Mooijman KA; VDL; Z&O

    2018-01-01

    In 2016, it was shown that all 34 National Reference Laboratories (NRLs), 30 of which are located in the European Union, were able to detect high and low levels of Salmonella in minced chicken meat. Three NRLs reported Salmonella in one 'blank' minced meat sample. This was probably caused by the

  18. PCR-RFLP Analysis of a fliC Gene Fragment in Avian Salmonella Isolates

    Directory of Open Access Journals (Sweden)

    Zohreh Ebrahimvandi

    2014-07-01

    Full Text Available Background: Salmonella are a genus of zoonotic bacteria of worldwide economic and health importance. Members of Salmonella enterica subspecies enterica are mainly associated with warm-blooded vertebrates and are usually transmitted by ingestion of food or watercontaminated by infected feces. Objectives: The aim of this study was to apply a PCR-RFLP method based on the fliC gene to identify the serotypes of Salmonella isolates from Karaj, Iran. Materials and Methods: A total of 30 Salmonella isolates were serotyped by specific antisera. For the PCR-RFLP method based on the fliC gene, extracted DNA was used as the template for amplifying the fliC gene (1500 bp using specific primers. PCR products were subjected to digestion using HhaI restriction endonuclease. Results: This study determined 30 serotypes as Salmonella durban (56.6%, Salmonella uno (23.3%, Salmonella enteritidis (3.3%, Salmonella tinda (3.3%, Salmonella mjimweme (3.3%, Salmonella Thompson (3.3%, Salmonella sIIO8 (3.3 % and Salmonella sIIO7 (3.3%. Observations indicated that HhaI is able to discriminate Salmonella tinda and Salmonella thompson, yet Salmonella enteritidis, Salmonella durban and Salmonella mjimweme had the same pattern with this enzyme. Also Salmonella sIIO8, Salmonella sIIO7 and Salmonella uno showed the same pattern. Thus, regarding the size and the number of resulting fragments from this enzyme, four patterns were obtained for HhaI. Conclusion: A large number of Salmonella serotypes need to be analyzed by the PCR-RFLP method and different enzymes must be used to give reliable results.

  19. Septic arthritis of the ankle due to Salmonella enteritidis.

    LENUS (Irish Health Repository)

    Dineen, Patrick F

    2011-06-01

    Salmonella septic arthritis in healthy, immunocompetent patients is extremely rare. We present the case of a 70-year-old man who presented with a one-day history of painful swelling of his ankle from which was aspirated pus which subsequently grew Salmonella enteritidis. There was no history of trauma or symptoms consistent with Salmonella enterocolitis. Our patient recovered fully after two weeks on intravenous ceftriaxone and six weeks on oral ciprofloxacin. Salmonella is a notifiable disease in the European Union and the United States of America, and is associated with outbreaks as a result of food contamination. The nature of Salmonella arthritis and its appropriate management are outlined.

  20. SALMONELLA SPECIES

    African Journals Online (AJOL)

    DR. AMINU

    ... of Salmonella species serotypes in relation to age and sex among children, ..... However, most antimicrobials show sufficient selective toxicity to be of value in ... salmonellosis should be given good attention (Barrow et al., 2007). To reduce ...

  1. Anaerobiosis induced virulence of Salmonella typhi

    DEFF Research Database (Denmark)

    Kapoor, Sarika; Singh, R D; Sharma, P C

    2002-01-01

    , we examined the effect of anaerobiosis on the virulence of Salmonella Typhi, a Gram negative bacteria which invades through the gut mucosa and is responsible for typhoid fever. METHODS: Salmonella Typhi (ty2) was cultured in aerobic and anaerobic conditions to compare its virulence by rabbit ileal...

  2. Evaluation of commercial kit based on loop-mediated isothermal amplification for rapid detection of low levels of uninjured and injured Salmonella on duck meat, bean sprouts, and fishballs in Singapore.

    Science.gov (United States)

    Lim, Hazel Sin Yue; Zheng, Qianwang; Miks-Krajnik, Marta; Turner, Matthew; Yuk, Hyun-Gyun

    2015-06-01

    The objective of this study was to evaluate performance of the commercial kit based on loop-mediated isothermal amplification (LAMP) in comparison with the International Organization for Standardization method for detecting uninjured and sublethally injured Salmonella cells artificially inoculated at levels of 10(0) and 10(1) CFU/25 g on raw duck wing, raw mung bean sprouts, and processed fishballs. Injured cells were prepared by a heat treatment for duck wings and fishball samples and a chlorine treatment for bean sprout samples. Additionally, a validation study was performed on naturally contaminated food samples sold in Singapore. A total of 110 samples of each commodity were analyzed in this study. Regardless of inoculum levels, the detection by the commercial LAMP kit showed 100% sensitivity and specificity for both inoculated and uninoculated samples compared with the International Organization for Standardization method, with the exception of bean sprout samples. Only 20% of bean sprout samples inoculated with 10(0) CFU/25 g injured Salmonella cells were positive by using the commercial LAMP-based kit. However, all negative samples became positive following a secondary enrichment in Rappaport-Vassiliadis medium with soy broth or after concentration by centrifugation. These results suggest that secondary enrichment or centrifugation should be considered as an additional step to increase the sensitivity of the commercial LAMP-based kit with low numbers of injured target cells in samples with high background microflora (such as mung bean sprouts). The validation study also showed that the commercial LAMP-based kit provided 91% sensitivity and 95% specificity for naturally contaminated samples. Thus, this study demonstrates that the commercial LAMP-based kit might be a cost-effective method, as this system could provide rapid, accurate detection of both uninjured and injured Salmonella cells on raw duck wings, raw mung bean sprouts, and processed fishballs in

  3. 76 FR 81513 - Guidance for Industry: Prevention of Salmonella

    Science.gov (United States)

    2011-12-28

    ...] Guidance for Industry: Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and... ``Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and Transportation.'' The... final rule ``Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and...

  4. Test results of Salmonella serotyping in the Member States of the European Union. (Collaborative study III amongst the National Reference Laboratories for Salmonella)

    NARCIS (Netherlands)

    Voogt N; Maas HME; Leeuwen WJ van; Henken AM; MGB

    1998-01-01

    Het Communautair Referentie Laboratorium (CRL) voor Salmonella heeft een derde ringonderzoek voor de serotypering van Salmonella georganiseerd. Alle Nationale Referentie Laboratoria (NRLs) voor Salmonella van de Europese Unie deden aan het onderzoek mee. Het belangrijkste doel was het

  5. Transmission of Salmonella between wildlife and meat-production animals in Denmark

    DEFF Research Database (Denmark)

    Skov, M. N.; Madsen, J. J.; Rahbek, C.

    2008-01-01

    Aims: To investigate the transmission of Salmonella spp. between production animals (pigs and cattle) and wildlife on production animal farms in Denmark. Methods and Results: In the winter and summer of 2001 and 2002, 3622 samples were collected from Salmonella-infected and noninfected herds...... of pigs and cattle and surrounding wildlife. Salmonella was detected in wildlife on farms carrying Salmonella-positive production animals and only during the periods when Salmonella was detected in the production animals. The presence of Salmonella Typhimurium in wild birds significantly correlated...... to their migration pattern and food preference. Conclusions: Salmonella was transmitted from infected herds of production animals (cattle and pigs) to wildlife that lived amongst or in close proximity to them. Significance and Impact of the Study: Salmonella in animal food products is associated with the occurrence...

  6. Prevalence and susceptibility of salmonella Typhi and salmonella ...

    African Journals Online (AJOL)

    Methods: Blood samples collected from presumptive typhoid fever patients from Ahmadu Bello University (ABU), Federal College of Education (FCE) and presumptive typhoid fever patients that attended two private clinics (Salama Clinics and Savanna Polyclinics) in Zaria were cultured for Salmonella species and identified ...

  7. Salmonella bacteraemia among healthcare workers and their dependents

    International Nuclear Information System (INIS)

    Raza, A.; Sultan, F.; Mahboob, A.; Nazeer, S. H.; Nizammudin, S.

    2014-01-01

    Objectives: To determine the incidence and resistance pattern of Salmonella infection in healthcare workers and their dependents. Methods: The retrospective analysis was conducted at Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, and comprised records of employees and their dependents with bacteraemia from January 2007 to December 2011. Person-years were calculated using data from the human resources department. SPSS 19 was used for statistical analyses. Results: Of the total 2532 records available, 82(3.23%) patients were identified with Salmonella bacteraemia. Of them, 34(41.5%) patients were in age group 1-10, 15(18.3%) in 11-20, 26(31.7%) in 21-30, and 7(8.5%) were above 30 years. Besides, 48(58.5%) were males. Salmonella typhi was found in 44(53.7%) patients, Salmonella paratyphi A in 35(42.7%) and Salmonella species in 3(3.7%) patients. The yearly incidence of Salmonella infection in the study population ranged from 206 to 596 per 100000 person-years. Ciprofloxacin resistance was noted to be 56 (68.2%) followed by Ampicillin 29 (35.3%) and Co-trimoxazole 24 (29.2%). No strains were resistant to Cefiximeor Ceftriaxone. Conclusion: The yearly incidence of Salmonella bacteraemia ranged from 200 to 600 per 100000 person years. There was significant quinolone resistance among the isolates. (author)

  8. A rapid and specific detection of pathogenic serovar Salmonella typhimurium by loop-mediated isothermal amplification method (LAMP

    Directory of Open Access Journals (Sweden)

    Hadi Ravan

    2017-09-01

    Discussion and conclusion: As a result of a high sensitivity and specificity of the method as well as its low cost per assay, it could be concluded that the present LAMP assay is a powerful, accurate, and efficient method for detecting pathogenic serovar Salmonella typhimurium in food-processing industries and diagnostic laboratories.

  9. In vivo IFN-γ secretion by NK cells in response to Salmonella typhimurium requires NLRC4 inflammasomes.

    Directory of Open Access Journals (Sweden)

    Andreas Kupz

    Full Text Available Natural killer (NK cells are a critical part of the innate immune defense against viral infections and for the control of tumors. Much less is known about how NK cells contribute to anti-bacterial immunity. NK cell-produced interferon gamma (IFN-γ contributes to the control of early exponential replication of bacterial pathogens, however the regulation of these events remains poorly resolved. Using a mouse model of invasive Salmonellosis, here we report that the activation of the intracellular danger sensor NLRC4 by Salmonella-derived flagellin within CD11c+ cells regulates early IFN-γ secretion by NK cells through the provision of interleukin 18 (IL-18, independently of Toll-like receptor (TLR-signaling. Although IL18-signalling deficient NK cells improved host protection during S. Typhimurium infection, this increased resistance was inferior to that provided by wild-type NK cells. These findings suggest that although NLRC4 inflammasome-driven secretion of IL18 serves as a potent activator of NK cell mediated IFN-γ secretion, IL18-independent NK cell-mediated mechanisms of IFN-γ secretion contribute to in vivo control of Salmonella replication.

  10. Saccharomyces boulardii prevention of the hepatic injury induced by Salmonella Enteritidis infection.

    Science.gov (United States)

    Wu, Daichao; Teng, Da; Wang, Xiumin; Dai, Changsong; Wang, Jianhua

    2014-10-01

    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.

  11. Pathogenicity, Epidemiology and Virulence Factors of Salmonella species: A Review

    Directory of Open Access Journals (Sweden)

    Tamègnon Victorien DOUGNON

    2017-12-01

    Full Text Available Salmonella infections are major public health problems worldwide. The hereby review aimed to establish an overview on the pathogenicity, epidemiology and virulence factors of Salmonella spp. in the world. A systematic search was conducted online using the keywords ‘Salmonella’, ‘Salmonella spp.’, ‘Salmonella spp. Epidemiology’, ‘virulence factors of Salmonella spp. in the world’, ‘bacteria responsible for the contamination of meat products’, ‘non-typhoid salmonella’. These keywords were entered into databases such as PubMed and Google Scholar using mainly French language. The obtained articles were included based on the reliability of their source, the study area (usually Benin and Africa and the subject. The review revealed that Salmonella spp. is motile Gram-negative rod-shaped bacteria, of the family Enterobacteriaceae, currently counting more than 2,600 serovars. Human contamination occurs through the ingestion of contaminated water and food and can cause gastroenteritis or typhoid fever, which are two serious public health problems. A gene set constituting the pathogenicity islands determines the pathogenesis of Salmonella spp. The diagnosis is based on bacteriological, serological and molecular techniques. Salmonella infections are usually treated using antibiotics; however, emergence of antibiotic resistance in these microorganisms suggests that the anti-salmonella control should explore new sources such as medicinal plants

  12. Prevalence of Salmonella spp. in oysters in the United States.

    Science.gov (United States)

    Brands, Danielle A; Inman, Allison E; Gerba, Charles P; Maré, C John; Billington, Stephen J; Saif, Linda A; Levine, Jay F; Joens, Lynn A

    2005-02-01

    Food-borne diseases such as salmonellosis can be attributed, in part, to the consumption of raw oysters. To determine the prevalence of Salmonella spp. in oysters, oysters harvested from 36 U.S. bays (12 each from the West, East, and Gulf coasts in the summer of 2002, and 12 bays, four per coast, in the winter of 2002-2003) were tested. Salmonella was isolated from oysters from each coast of the United States, and 7.4% of all oysters tested contained Salmonella. Isolation tended to be bay specific, with some bays having a high prevalence of Salmonella, while other bays had none. Differences in the percentage of oysters from which Salmonella was isolated were observed between the summer and winter months, with winter numbers much lower probably due to a variety of weather-related events. The vast majority (78/101) of Salmonella isolates from oysters were Salmonella enterica serovar Newport, a major human pathogen, confirming the human health hazard of raw oyster consumption. Contrary to previous findings, no relationship was found between the isolation of fecal coliforms and Salmonella from oysters, indicating a necessity for specific monitoring for Salmonella and other pathogens rather than the current reliance on fecal coliform testing.

  13. Thirteenth CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp. : Dertiende CRL-Salmonella ringonderzoek voor de typering van Salmonella spp.

    NARCIS (Netherlands)

    Berk PA; Maas HME; de Pinna E; Mooijman KA; LZO; cib

    2010-01-01

    De Nationale Referentie Laboratoria (NRL's) van de 27 Europese lidstaten scoorden goed bij de kwaliteitscontrole op Salmonella-typering in 2008. Vier laboratoria hadden hiervoor een herkansing nodig. Daarnaast is een analyse van alle NRL's als groep uitgevoerd, waaruit bleek dat zij 97 % van de

  14. Sixteenth EURL-Salmonella interlaboratory comparison study on typing of Salmonella spp. : Zestiende EURL-Salmonella ringonderzoek voor de typering van Salmonella spp.

    NARCIS (Netherlands)

    Jacobs-Reitsma WF; Pol-Hofstad IE; Maas HME; de Pinna E; Mooijman KA; LZO; cib

    2012-01-01

    De 28 Nationale Referentie Laboratoria (NRL's) van de 27 Europese lidstaten scoorden in 2011 goed bij de kwaliteitscontrole om Salmonella te typeren. Twee laboratoria hadden hiervoor een herkansing nodig. Alle NRL's samen konden gemiddeld genomen aan 97 procent van de geteste stammen de juiste naam

  15. Comparative Genomics of 28 Salmonella enterica Isolates: Evidence for CRISPR-Mediated Adaptive Sublineage Evolution ▿†

    OpenAIRE

    Fricke, W. Florian; Mammel, Mark K.; McDermott, Patrick F.; Tartera, Carmen; White, David G.; LeClerc, J. Eugene; Ravel, Jacques; Cebula, Thomas A.

    2011-01-01

    Despite extensive surveillance, food-borne Salmonella enterica infections continue to be a significant burden on public health systems worldwide. As the S. enterica species comprises sublineages that differ greatly in antigenic representation, virulence, and antimicrobial resistance phenotypes, a better understanding of the species' evolution is critical for the prediction and prevention of future outbreaks. The roles that virulence and resistance phenotype acquisition, exchange, and loss pla...

  16. Salmonella burden in Lebanon.

    Science.gov (United States)

    Malaeb, M; Bizri, A R; Ghosn, N; Berry, A; Musharrafieh, U

    2016-06-01

    Salmonellosis is a disease that represents a major public health concern in both developing and developed countries. The aim of this article is to evaluate the public health burden of Salmonella illness in Lebanon. The current scope of the Salmonella infection problem was assessed in relation to disease incidence and distribution with respect to age, gender and district. Factors that provide a better understanding of the magnitude of the problem were explored and highlighted. Data reported to the Epidemiologic Surveillance Department at the Lebanese Ministry of Public Health between 2001 and 2013 was reviewed. Information obtained was compared to information reported regionally and globally. The estimated true incidence was derived using multipliers from the CDC and Jordan. A literature review of all published data from Lebanon about Salmonella susceptibility/resistance patterns and its serious clinical complications was conducted. The estimated incidence was 13·34 cases/100 000 individuals, most cases occurred in the 20-39 years age group with no significant gender variation. Poor and less developed districts of Lebanon had the highest number of cases and the peak incidence was in summer. Reflecting on the projected incidence derived from the use of multipliers indicates a major discrepancy between what is reported and what is estimated. We conclude that data about Salmonella infection in Lebanon and many Middle Eastern and developing countries lack crucial information and are not necessarily representative of the true incidence, prevalence and burden of illness.

  17. Antimicrobial resistance in zoonotic nontyphoidal Salmonella: an alarming trend?

    Science.gov (United States)

    Michael, G B; Schwarz, S

    2016-12-01

    Zoonotic bacteria of the genus Salmonella have acquired various antimicrobial resistance properties over the years. The corresponding resistance genes are commonly located on plasmids, transposons, gene cassettes, or variants of the Salmonella Genomic Islands SGI1 and SGI2. Human infections by nontyphoidal Salmonella isolates mainly result from ingestion of contaminated food. The two predominantly found Salmonella enterica subsp. enterica serovars in the USA and in Europe are S. Enteritidis and S. Typhimurium. Many other nontyphoidal Salmonella serovars have been implicated in foodborne Salmonella outbreaks. Summary reports of the antimicrobial susceptibility patterns of nontyphoidal Salmonella isolates over time suggest a moderate to low level of antimicrobial resistance and multidrug-resistance. However, serovar-specific analyses showed in part a steady state, a continuous decline, or a recent increase in resistance to certain antimicrobial agents. Resistance to critically important antimicrobial agents, e.g. third-generation cephalosporins and (fluoro)quinolones is part of many monitoring programmes and the corresponding results confirm that extended-spectrum β-lactamases are still rarely found in nontyphoidal Salmonella serovars, whereas resistance to (fluoro)quinolones is prevalent at variable frequencies among different serovars from humans and animals in different countries. Although it is likely that nontyphoidal Salmonella isolates from animals represent a reservoir for resistance determinants, it is mostly unknown where and when Salmonella isolates acquired resistance properties and which exchange processes have happened since then. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  18. Elimination of salmonella from animal glandular products.

    Science.gov (United States)

    De Fiebre, C W; Burck, K T; Feldman, D

    1969-03-01

    Methods for the elimination of salmonellae from selected powdered pharmaceuticals of animal glandular origin were studied. Terminal heat treatment under carefully controlled conditions was effective for pancreatin-a powder containing proteolytic, amylolytic, and lipolytic enzymes prepared from hog pancreas glands. Use of this method resulted in a significant reduction in the number of salmonella-positive batches and also reduced the testing procedures required to confirm the absence of viable salmonellae among the majority of samples tested. Powders such as stomach substance and thyroid, in which the biological activity is not enzyme in nature, were treated successfully with acidified organic solvents. Other methods were investigated but were not suitable because of a deleterious effect on the biological activity or physical properties of the product or an inability to effect salmonella elimination.

  19. Elimination of Salmonellae from Animal Glandular Products

    Science.gov (United States)

    De Fiebre, Conrad W.; Burck, Kenneth T.; Feldman, David

    1969-01-01

    Methods for the elimination of salmonellae from selected powdered pharmaceuticals of animal glandular origin were studied. Terminal heat treatment under carefully controlled conditions was effective for pancreatin—a powder containing proteolytic, amylolytic, and lipolytic enzymes prepared from hog pancreas glands. Use of this method resulted in a significant reduction in the number of salmonella-positive batches and also reduced the testing procedures required to confirm the absence of viable salmonellae among the majority of samples tested. Powders such as stomach substance and thyroid, in which the biological activity is not enzyme in nature, were treated successfully with acidified organic solvents. Other methods were investigated but were not suitable because of a deleterious effect on the biological activity or physical properties of the product or an inability to effect salmonella elimination. PMID:5780395

  20. Efeitos da Salmonella Enteritidis experimentalmente inoculada na saúde gastrintestinal de perus Effects of experimentally inoculated Salmonella Enteritidis on the gastrointestinal health of turkeys

    Directory of Open Access Journals (Sweden)

    Carla Yoko Tanikawa de Andrade

    2012-03-01

    Full Text Available Avaliaram-se os efeitos de Salmonella Enteritidis sobre a colonização e o desenvolvimento do trato intestinal, a conversão alimentar e o ganho de peso em perus. Um total de 135 perus de corte de 1 dia foi distribuído em três tratamentos: controle; perus oriundos de ovos inoculados com Salmonella Enteritidis via casca e perus desafiados com água de bebida com Salmonella Enteritidis. Aos 10, 20 e 28 dias, avaliaram-se as variáveis de desempenho e coletaram-se amostras para avaliação bacteriana, biometria e histomorfometria. Realizaram-se também, nos dias 1, 15 e 28 de idade, coletas de mecônio/excretas de todas as aves. A colonização intestinal aumentou durante a fase inicial quando Salmonella foi inoculada via casca. O intestino apresentou maior peso ao 1º, 10º e 28º dias quando Salmonella esteve presente, sem diferença no comprimento. Salmonella Enteritidis foi capaz de colonizar o trato intestinal, estabelecer infecção, reduzir o desempenho das aves e modificar as estruturas celulares do intestino. A contaminação da casca do ovo antes da incubação propiciou a ocorrência de infecções ao nascimento, e a frequência de isolamento de Salmonella Enteritidis persistiu até 28 dias de idade. A inoculação de Salmonella pela água de bebida gerou aves infectadas, porém com menor nível de infecção com o avançar da idade. O desempenho de aves inoculadas com Salmonella Enteritidis é menor e isso confirma potenciais prejuízos para a produção avícola.The effects of Salmonella Enteritidis on the colonization and development of the intestinal tract, feed conversion and weight gain were evaluated. A total of 135 day old turkeys were assigned to three treatments: control; turkeys from eggs inoculated with Salmonella Enteritidis via shell and turkeys challenged with drinking water with Salmonella Enteritidis. At 10, 20 and 28 days, the performance variables were evaluated and samples were collected to perform bacterial

  1. The eleventh CRL-Salmonella workshop, 9 May 2006, Saint Malo, France

    NARCIS (Netherlands)

    Mooijman KA; MGB

    2006-01-01

    De elfde workshop georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella) werd gehouden op 9 mei 2006 in Saint Malo, Frankrijk. Deelnemers waren vertegenwoordigers van de nationale Referentie Laboratoria voor Salmonella (NRLs-Salmonella) van de lidstaten van de

  2. Bilateral breast abscesses due to Salmonella Enterica serotype typhi

    Directory of Open Access Journals (Sweden)

    Gagandeep Singh

    2011-01-01

    Full Text Available Focal infection is an uncommon complication of Salmonella septicemia, particularly in immunocompetent patients. The localization of Salmonella infection to breast tissue is regarded as a rare event. We report a case of bilateral breast abscesses due to Salmonella enterica serotype Typhi in a nonlactating female and highlight the fact that Salmonella spp. should be included in differential diagnosis of abscesses in individuals coming from endemic areas with the history of recent typhoid fever and should be treated accordingly.

  3. Coconut and Salmonella Infection

    Science.gov (United States)

    Schaffner, Carl P.; Mosbach, Klaus; Bibit, Venuso C.; Watson, Colin H.

    1967-01-01

    Raw, unprocessed coconut supports the growth of salmonellae as well as that of other enteric bacteria, salmonellae being particularly resistant to subsequent desiccation. Original contamination is not due to carriers or to polluted water supplies, but to contact with bacteria-containing soils followed by dispersion via infected coconut milk and shells. Pasteurization of raw coconut meat in a water bath at 80 C for 8 to 10 min effectively killed such bacteria, did not injure the product, and provided a prophylactic method now widely used by the coconut industry. PMID:5340650

  4. Salmonella in wastes produced at commercial poultry farms.

    Science.gov (United States)

    Kraft, D J; Olechowski-Gerhardt, C; Berkowitz, J; Finstein, M S

    1969-11-01

    Composite samples of freshly voided excreta from 91 poultry houses were tested qualitatively for Salmonella; 26 (29%) were positive. The houses were located on 36 farms, 18 of which (50%) yielded one or more positive samples. In a separate, quantitative study, Salmonella densities ranged from less than 1 to over 34,000 per g of excreta (dry weight). High densities were noted in waste from cage houses, but not in waste from floor houses (litter or wire floors). Salmonella-shedding chickens were located in only one small area of the row of cages examined in detail. A total of 15 Salmonella serotypes were identified during the study.

  5. Salmonella Typhimurium pneumonia in a patient with multiple myeloma.

    Science.gov (United States)

    Khan, Sadia; Kumar, V Anil; Sidharthan, Neeraj; Mehta, Asmita; Backer, Binita; Dinesh, Kavitha R

    2015-04-01

    Pneumonia due to non-typhoidal Salmonella is a rarely reported entity. A fatal case of Salmonella pneumonia is reported here where Salmonella Typhimurium was isolated from the endotracheal aspirate and blood culture. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  6. 78 FR 42451 - Animal Feeds Contaminated With Salmonella Microorganisms

    Science.gov (United States)

    2013-07-16

    .... FDA-2013-N-0253] Animal Feeds Contaminated With Salmonella Microorganisms AGENCY: Food and Drug... revoking an advisory opinion on animal feeds contaminated with Salmonella microorganisms. This action is... articulated in a final compliance policy guide (CPG) on Salmonella in food for animals. DATES: This rule is...

  7. Comparing validation of four ELISA-systems for detection of Salmonella derby- and Salmonella infantis-infected pigs.

    Science.gov (United States)

    Roesler, Uwe; Szabo, Istvan; Matthies, Claudia; Albrecht, Kerstin; Leffler, Martin; Scherer, Kathrin; Nöckler, Karsten; Lehmann, Jörg; Methner, Ulrich; Hensel, Andreas; Truyen, Uwe

    2011-01-01

    The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs.Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were orally infected with a porcine S. Infantis or S. Derby strain. Clinical and bacteriological parameters were monitored weekly during an observation period of 130 days after infection and serum samples were investigated in parallel with the respective ELISAs. Apparently, the LPS-based ELISA systems used in this study failed to recognize S. Infantis-infected pigs although those animals shed the pathogen in high amounts throughout the study until day 81 post infection (p. i.). In contrast, the isotype-specific Salmonella Typhimurium whole-cell-lysate based ELISA was capable of detecting Salmonella-infected pigs from day ten p. i. at all tested serotypes and revealed the highest sensitivity in detection of S. Infantis-infected pigs. Furthermore, it became apparent that the often used surveillance cut-off value of 40 OD% is not appropriate for intra-vitam detection of S. Infantis- and S. Derby-infected pigs. In contrast, the cut-off values of the ELISAs given by the suppliers result in considerable higher detection rates.

  8. Increased colon cancer risk after severe Salmonella infection

    OpenAIRE

    Mughini-Gras, Lapo; Schaapveld, Michael; Kramers, Jolanda; Mooij, Sofie; Neefjes-Borst, E. Andra; van Pelt, Wilfrid; Neefjes, Jacques

    2018-01-01

    Background Colon cancer constitutes one of the most frequent malignancies. Previous studies showed that Salmonella manipulates host cell signaling pathways and that Salmonella Typhimurium infection facilitates colon cancer development in genetically predisposed mice. This epidemiological study examined whether severe Salmonella infection, usually acquired from contaminated food, is associated with increased colon cancer risk in humans. Methods and findings We performed a nationwide registry-b...

  9. Chasing Salmonella Typhimurium in free range egg production system.

    Science.gov (United States)

    Chousalkar, Kapil; Gole, Vaibhav; Caraguel, Charles; Rault, Jean-Loup

    2016-08-30

    Free range production systems are becoming a major source of egg production in Australia and worldwide. This study investigated shedding and ecology of Salmonella Typhimurium and Salmonella species in a free range layer flock, wild birds and foxes in the vicinity of the free range farm in different seasons. Shedding of Salmonella was significantly higher in summer. Within the shed, overall, Salmonella prevalence was highest in dust. Corticosterone level in faeces was highest in spring and lowest in winter. There was no direct association between the Salmonella shedding (MPN/gm) and corticosterone levels in faeces. Salmonella Typhimurium MLVA types isolated from fox and wild birds were similar to MLVA types isolated from layer flock and reported during human food borne illness. Wild birds and foxes appear to play an important role in S. Typhimurium ecology and food safety. Environmental factors could play a role in evolution of S. Typhimurium in free range environment. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  10. Increased colon cancer risk after severe Salmonella infection.

    Directory of Open Access Journals (Sweden)

    Lapo Mughini-Gras

    Full Text Available Colon cancer constitutes one of the most frequent malignancies. Previous studies showed that Salmonella manipulates host cell signaling pathways and that Salmonella Typhimurium infection facilitates colon cancer development in genetically predisposed mice. This epidemiological study examined whether severe Salmonella infection, usually acquired from contaminated food, is associated with increased colon cancer risk in humans.We performed a nationwide registry-based study to assess colon cancer risk after diagnosed Salmonella infection. National infectious disease surveillance records (1999-2015 for Dutch residents aged ≥20 years when diagnosed with salmonellosis (n = 14,264 were linked to the Netherlands Cancer Registry. Salmonella-infected patients were laboratory-confirmed under medical consultation after 1-2 weeks of illness. These datasets also contained information on Salmonella serovar and type of infection. Colon cancer risk (overall and per colon subsite among patients with a diagnosed Salmonella infection was compared with expected colon cancer risk in the general population. Data from the nationwide registry of histo- and cytopathology (PALGA and Statistics Netherlands (CBS allowed assessing potential effects of age, gender, latency, socioeconomic status, genetic predisposition, inflammatory bowel disease (IBD, and tumor features. We found that compared to the general population, colon cancer risk was significantly increased (standardized incidence ratio [SIR] 1.54; 95%CI 1.09-2.10 among patients with Salmonella infection diagnosed <60 years of age. Such increased risk concerned specifically the ascending/transverse colon (SIR 2.12; 95%CI 1.38-3.09 after S. Enteritidis infection (SIR 2.97; 95%CI 1.73-4.76. Salmonellosis occurred more frequently among colon cancer patients with pre-infectious IBD, a known risk factor for colon cancer. Colon tumors of patients with a history of Salmonella infection were mostly of low grade

  11. Increased colon cancer risk after severe Salmonella infection

    Science.gov (United States)

    Mooij, Sofie; Neefjes-Borst, E. Andra; van Pelt, Wilfrid; Neefjes, Jacques

    2018-01-01

    Background Colon cancer constitutes one of the most frequent malignancies. Previous studies showed that Salmonella manipulates host cell signaling pathways and that Salmonella Typhimurium infection facilitates colon cancer development in genetically predisposed mice. This epidemiological study examined whether severe Salmonella infection, usually acquired from contaminated food, is associated with increased colon cancer risk in humans. Methods and findings We performed a nationwide registry-based study to assess colon cancer risk after diagnosed Salmonella infection. National infectious disease surveillance records (1999–2015) for Dutch residents aged ≥20 years when diagnosed with salmonellosis (n = 14,264) were linked to the Netherlands Cancer Registry. Salmonella-infected patients were laboratory-confirmed under medical consultation after 1–2 weeks of illness. These datasets also contained information on Salmonella serovar and type of infection. Colon cancer risk (overall and per colon subsite) among patients with a diagnosed Salmonella infection was compared with expected colon cancer risk in the general population. Data from the nationwide registry of histo- and cytopathology (PALGA) and Statistics Netherlands (CBS) allowed assessing potential effects of age, gender, latency, socioeconomic status, genetic predisposition, inflammatory bowel disease (IBD), and tumor features. We found that compared to the general population, colon cancer risk was significantly increased (standardized incidence ratio [SIR] 1.54; 95%CI 1.09–2.10) among patients with Salmonella infection diagnosed transverse colon (SIR 2.12; 95%CI 1.38–3.09) after S. Enteritidis infection (SIR 2.97; 95%CI 1.73–4.76). Salmonellosis occurred more frequently among colon cancer patients with pre-infectious IBD, a known risk factor for colon cancer. Colon tumors of patients with a history of Salmonella infection were mostly of low grade. Conclusions Patients diagnosed with severe

  12. Salmonella infection and carriage in reptiles in a zoological collection.

    Science.gov (United States)

    Clancy, Meredith M; Davis, Meghan; Valitutto, Marc T; Nelson, Kenrad; Sykes, John M

    2016-05-01

    OBJECTIVE To identify important subspecies and serovars of Salmonella enterica in a captive reptile population and clinically relevant risk factors for and signs of illness in Salmonella-positive reptiles. DESIGN Retrospective cross-sectional study. ANIMALS 11 crocodilians (4 samples), 78 snakes (91 samples), 59 lizards (57 samples), and 34 chelonians (23 samples) at the Bronx Zoo from 2000 through 2012. PROCEDURES Data pertaining to various types of biological samples obtained from reptiles with positive Salmonella culture results and the reptiles themselves were analyzed to determine period prevalence of and risk factors for various Salmonella-related outcomes. RESULTS Serovar distribution differences were identified for sample type, reptile phylogenetic family, and reptile origin and health. Salmonella enterica subsp enterica was the most common subspecies in Salmonella cultures (78/175 [45%]), identified across all reptilian taxa. Salmonella enterica subsp diarizonae was also common (42/175 [24%]) and was recovered almost exclusively from snakes (n = 33), many of which had been clinically ill (17). Clinically ill reptiles provided 37% (64) of Salmonella cultures. Factors associated with an increased risk of illness in reptiles with a positive culture result were carnivorous diet and prior confiscation. Snakes had a higher risk of illness than other reptile groups, whereas lizards had a lower risk. Bony changes, dermatitis, and anorexia were the most common clinical signs. CONCLUSIONS AND CLINICAL RELEVANCE This study provided new information on Salmonella infection or carriage and associated clinical disease in reptiles. Associations identified between serovars or subspecies and reptile groups or clinical disease can guide management of Salmonella-positive captive reptiles.

  13. Salmonella Dublin i oksekød, 2014

    DEFF Research Database (Denmark)

    Aabo, Søren; Hansen, Tina Beck

    Case-by-case overvågningen af dansk og udenlandsk fersk kød af kvæg ophørte ved årsskiftet til 2013 som følge af meget få fund. I 2012 blev der imidlertid påvist Salmonella i 14,3 % af de undersøgte partier af fersk dansk oksekød, mens man i samme periode ikke så den samme stigning i fund af...... Salmonella på slagterierne. Det er derfor muligt, at der er andre kilder til salmonellas forekomst i det ferske oksekød. En del oksekød opskæres typisk på andre virksomheder end på slagteriet, og krydskontaminering med Salmonella her kan derfor være en af årsagerne til det høje fund, da disse virksomheder...... typisk forarbejder store mængder dansk og udenlandsk kød i de samme produktionslinjer. Siden planlægningen af dette projekt er forekomsten af Salmonella Dublin faldet i oksekød, men projektet er blevet gennemført som oprindeligt planlagt. Formålet med dette projekt har været at afklare forekomsten af...

  14. Molecular characterization of Salmonella Paratyphi B dT+ and Salmonella Heidelberg from poultry and retail chicken meat in Colombia by pulsed-field gel electrophoresis

    Science.gov (United States)

    Salmonella Paratyphi B dT+ variant (also termed Salmonella Java) and Salmonella Heidelberg are human pathogens frequently isolated from poultry. As a step towards implementing the Colombian Integrated Program for Antimicrobial Resistant Surveillance (COIPARS), this study characterized molecular patt...

  15. Salmonella serotypes in reptiles and humans, French Guiana.

    Science.gov (United States)

    Gay, Noellie; Le Hello, Simon; Weill, François-Xavier; de Thoisy, Benoit; Berger, Franck

    2014-05-14

    In French Guiana, a French overseas territory located in the South American northern coast, nearly 50% of Salmonella serotypes isolated from human infections belong to serotypes rarely encountered in metropolitan France. A reptilian source of contamination has been investigated. Between April and June 2011, in the area around Cayenne, 151 reptiles were collected: 38 lizards, 37 snakes, 32 turtles, 23 green iguanas and 21 caimans. Cloacal swab samples were collected and cultured. Isolated Salmonella strains were identified biochemically and serotyped. The overall carriage frequency of carriage was 23.2% (95% confidence interval: 16.7-30.4) with 23 serotyped strains. The frequency of Salmonella carriage was significantly higher for wild reptiles. Near two-thirds of the Salmonella serotypes isolated from reptiles were also isolated from patients in French Guiana. Our results highlight the risk associated with the handling and consumption of reptiles and their role in the spread of Salmonella in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Troxerutin Attenuates Enhancement of Hepatic Gluconeogenesis by Inhibiting NOD Activation-Mediated Inflammation in High-Fat Diet-Treated Mice.

    Science.gov (United States)

    Zhang, Zifeng; Wang, Xin; Zheng, Guihong; Shan, Qun; Lu, Jun; Fan, Shaohua; Sun, Chunhui; Wu, Dongmei; Zhang, Cheng; Su, Weitong; Sui, Junwen; Zheng, Yuanlin

    2016-12-25

    Recent evidence suggests that troxerutin, a trihydroxyethylated derivative of natural bioflavonoid rutin, exhibits beneficial effects on diabetes-related symptoms. Here we investigated the effects of troxerutin on the enhancement of hepatic gluconeogenesis in high-fat diet (HFD)-treated mice and the mechanisms underlying these effects. Mice were divided into four groups: Control group, HFD group, HFD + Troxerutin group, and Troxerutin group. Troxerutin was treated by daily oral administration at doses of 150 mg/kg/day for 20 weeks. Tauroursodeoxycholic acid (TUDCA) was used to inhibit endoplasmic reticulum stress (ER stress). Our results showed that troxerutin effectively improved obesity and related metabolic parameters, and liver injuries in HFD-treated mouse. Furthermore, troxerutin significantly attenuated enhancement of hepatic gluconeogenesis in HFD-fed mouse. Moreover, troxerutin notably suppressed nuclear factor-κB (NF-κB) p65 transcriptional activation and release of inflammatory cytokines in HFD-treated mouse livers. Mechanismly, troxerutin dramatically decreased Nucleotide oligomerization domain (NOD) expression, as well as interaction between NOD1/2 with interacting protein-2 (RIP2), by abating oxidative stress-induced ER stress in HFD-treated mouse livers, which was confirmed by TUDCA treatment. These improvement effects of troxerutin on hepatic glucose disorders might be mediated by its anti-obesity effect. In conclusion, troxerutin markedly diminished HFD-induced enhancement of hepatic gluconeogenesis via its inhibitory effects on ER stress-mediated NOD activation and consequent inflammation, which might be mediated by its anti-obesity effect.

  17. Troxerutin Attenuates Enhancement of Hepatic Gluconeogenesis by Inhibiting NOD Activation-Mediated Inflammation in High-Fat Diet-Treated Mice

    Directory of Open Access Journals (Sweden)

    Zifeng Zhang

    2016-12-01

    Full Text Available Recent evidence suggests that troxerutin, a trihydroxyethylated derivative of natural bioflavonoid rutin, exhibits beneficial effects on diabetes-related symptoms. Here we investigated the effects of troxerutin on the enhancement of hepatic gluconeogenesis in high-fat diet (HFD-treated mice and the mechanisms underlying these effects. Mice were divided into four groups: Control group, HFD group, HFD + Troxerutin group, and Troxerutin group. Troxerutin was treated by daily oral administration at doses of 150 mg/kg/day for 20 weeks. Tauroursodeoxycholic acid (TUDCA was used to inhibit endoplasmic reticulum stress (ER stress. Our results showed that troxerutin effectively improved obesity and related metabolic parameters, and liver injuries in HFD-treated mouse. Furthermore, troxerutin significantly attenuated enhancement of hepatic gluconeogenesis in HFD-fed mouse. Moreover, troxerutin notably suppressed nuclear factor-κB (NF-κB p65 transcriptional activation and release of inflammatory cytokines in HFD-treated mouse livers. Mechanismly, troxerutin dramatically decreased Nucleotide oligomerization domain (NOD expression, as well as interaction between NOD1/2 with interacting protein-2 (RIP2, by abating oxidative stress-induced ER stress in HFD-treated mouse livers, which was confirmed by TUDCA treatment. These improvement effects of troxerutin on hepatic glucose disorders might be mediated by its anti-obesity effect. In conclusion, troxerutin markedly diminished HFD-induced enhancement of hepatic gluconeogenesis via its inhibitory effects on ER stress-mediated NOD activation and consequent inflammation, which might be mediated by its anti-obesity effect.

  18. Anti-allergic activity of 2,4,6-trihydroxy-3-geranylacetophenone (tHGA) via attenuation of IgE-mediated mast cell activation and inhibition of passive systemic anaphylaxis

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Ji Wei; Israf, Daud Ahmad; Harith, Hanis Hazeera; Md Hashim, Nur Fariesha [Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400 (Malaysia); Ng, Chean Hui; Shaari, Khozirah [Faculty of Science, Universiti Putra Malaysia, Serdang 43300 (Malaysia); Tham, Chau Ling, E-mail: chauling@upm.edu.my [Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400 (Malaysia)

    2017-03-15

    tHGA, a geranyl acetophenone compound originally isolated from a local shrub called Melicope ptelefolia, has been previously reported to prevent ovalbumin-induced allergic airway inflammation in a murine model of allergic asthma by targeting cysteinyl leukotriene synthesis. Mast cells are immune effector cells involved in the pathogenesis of allergic diseases including asthma by releasing cysteinyl leukotrienes. The anti-asthmatic properties of tHGA could be attributed to its inhibitory effect on mast cell degranulation. As mast cell degranulation is an important event in allergic responses, this study aimed to investigate the anti-allergic effects of tHGA in cellular and animal models of IgE-mediated mast cell degranulation. For in vitro model of IgE-mediated mast cell degranulation, DNP-IgE-sensitized RBL-2H3 cells were pre-treated with tHGA before challenged with DNP-BSA to induce degranulation. For IgE-mediated passive systemic anaphylaxis, Sprague Dawley rats were sensitized by intraperitoneal injection of DNP-IgE before challenged with DNP-BSA. Both in vitro and in vivo models showed that tHGA significantly inhibited the release of preformed mediators (β-hexosaminidase and histamine) as well as de novo mediators (interleukin-4, tumour necrosis factor-α, prostaglandin D{sub 2} and leukotriene C{sub 4}). Pre-treatment of tHGA also prevented IgE-challenged RBL-2H3 cells and peritoneal mast cells from undergoing morphological changes associated with mast cell degranulation. These findings indicate that tHGA possesses potent anti-allergic activity via attenuation of IgE-mediated mast cell degranulation and inhibition of IgE-mediated passive systemic anaphylaxis. Thus, tHGA may have the potential to be developed as a mast cell stabilizer for the treatment of allergic diseases in the future. - Highlights: • The in vitro and in vivo mast cell stabilizing effects of tHGA were examined. • tHGA counteracts the plasma membrane deformation in degranulating mast

  19. Anti-allergic activity of 2,4,6-trihydroxy-3-geranylacetophenone (tHGA) via attenuation of IgE-mediated mast cell activation and inhibition of passive systemic anaphylaxis

    International Nuclear Information System (INIS)

    Tan, Ji Wei; Israf, Daud Ahmad; Harith, Hanis Hazeera; Md Hashim, Nur Fariesha; Ng, Chean Hui; Shaari, Khozirah; Tham, Chau Ling

    2017-01-01

    tHGA, a geranyl acetophenone compound originally isolated from a local shrub called Melicope ptelefolia, has been previously reported to prevent ovalbumin-induced allergic airway inflammation in a murine model of allergic asthma by targeting cysteinyl leukotriene synthesis. Mast cells are immune effector cells involved in the pathogenesis of allergic diseases including asthma by releasing cysteinyl leukotrienes. The anti-asthmatic properties of tHGA could be attributed to its inhibitory effect on mast cell degranulation. As mast cell degranulation is an important event in allergic responses, this study aimed to investigate the anti-allergic effects of tHGA in cellular and animal models of IgE-mediated mast cell degranulation. For in vitro model of IgE-mediated mast cell degranulation, DNP-IgE-sensitized RBL-2H3 cells were pre-treated with tHGA before challenged with DNP-BSA to induce degranulation. For IgE-mediated passive systemic anaphylaxis, Sprague Dawley rats were sensitized by intraperitoneal injection of DNP-IgE before challenged with DNP-BSA. Both in vitro and in vivo models showed that tHGA significantly inhibited the release of preformed mediators (β-hexosaminidase and histamine) as well as de novo mediators (interleukin-4, tumour necrosis factor-α, prostaglandin D 2 and leukotriene C 4 ). Pre-treatment of tHGA also prevented IgE-challenged RBL-2H3 cells and peritoneal mast cells from undergoing morphological changes associated with mast cell degranulation. These findings indicate that tHGA possesses potent anti-allergic activity via attenuation of IgE-mediated mast cell degranulation and inhibition of IgE-mediated passive systemic anaphylaxis. Thus, tHGA may have the potential to be developed as a mast cell stabilizer for the treatment of allergic diseases in the future. - Highlights: • The in vitro and in vivo mast cell stabilizing effects of tHGA were examined. • tHGA counteracts the plasma membrane deformation in degranulating mast cells. • t

  20. Parotid abscess due to salmonella enteritidis: A case report.

    Science.gov (United States)

    Reyes, Cesar V; Jensen, JoAnne D

    2006-01-01

    Salmonella infection of the parotid gland is rare. An instance in a 50-year-old man of Salmonella enteritidis parotiditis initially recognized by microbial culture of a fine needle aspiration cytology material is described. The identified predisposing factor was chronic alcoholic abuse. For the infection source, a carrier state of salmonella parotitis was postulated, which progressed to focal abscess and was subsequently complicated by bacteremia and hematogenous spread to the liver, spleen and lungs. Salmonella should be included in the differential consideration of head and neck abscesses in immunocompromised individuals and treated aggressively.

  1. Elimination of salmonella from fermented pork by gamma irradiation

    International Nuclear Information System (INIS)

    Noochpramul, K.; Loaharanu, P.

    1974-01-01

    A fermented pork product, locally known as ''Nham'', is usually contaminated with salmonella and occasionally with Trichinella spiralis and Taenea solium. This product is always eaten raw as cooking destroys its delicate flavour. A survey made on the MPN of salmonella revealed that much less than 100 salmonella was found in one gram of the product. Nham was inoculated with S. derby, S. anatum, S. newport, or S. paratyphi B, the most common serotypes of salmonella found in this product, at 10 6 , 10 4 , or 10 2 per gram. The inoculated product was irradiated by the gamma beam-650 Co-60 irradiator at 0, 0.1, 0.2, 0.3 or 0.4 Mrad. Dosage at 0.4 Mrad eliminated salmonella as much as 10 6 per g; 0.3 Mrad eliminated 10 6 /g of S. newport and S. paratyphi B and 10 4 /g of S. derby and S. anatum; and 0.2 Mrad eliminated 10 2 /g of all serotypes of salmonella in the product. No changes in the organoleptic properties of irradiated Nham was found when irradiated at 0.3 Mrad or less. Dosage at 0.2 Mrad appeared to be sufficient for commercial irradiation of Nham for the elimination of salmonella

  2. Test results of serotyping Salmonella strains in the Member States of the European Union (A collaborative study amongst the National Reference Laboratories for Salmonella)

    NARCIS (Netherlands)

    Voogt N; Maas HME; Leeuwen WJ van; Henken AM; MGB

    1997-01-01

    Het Communautair Referentie Laboratorium (CRL) voor Salmonella heeft een ringonderzoek voor de serotypering van Salmonella georganiseerd. De Nationale Referentie Laboratoria (NRLs) voor Salmonella uit 14 van de 15 lidstaten van de Europese Unie deden aan het onderzoek mee. Het doel was te

  3. Distributions of Salmonella Subtypes Differ between Two U.S. Produce-Growing Regions

    Science.gov (United States)

    Danyluk, Michelle D.; Worobo, Randy W.; Wiedmann, Martin

    2014-01-01

    Salmonella accounts for approximately 50% of produce-associated outbreaks in the United States, several of which have been traced back to contamination in the produce production environment. To quantify Salmonella diversity and aid in identification of Salmonella contamination sources, we characterized Salmonella isolates from two geographically diverse produce-growing regions in the United States. Initially, we characterized the Salmonella serotype and subtype diversity associated with 1,677 samples collected from 33 produce farms in New York State (NYS). Among these 1,677 samples, 74 were Salmonella positive, yielding 80 unique isolates (from 147 total isolates), which represented 14 serovars and 23 different pulsed-field gel electrophoresis (PFGE) types. To explore regional Salmonella diversity associated with production environments, we collected a smaller set of samples (n = 65) from South Florida (SFL) production environments and compared the Salmonella diversity associated with these samples with the diversity found among NYS production environments. Among these 65 samples, 23 were Salmonella positive, yielding 32 unique isolates (from 81 total isolates), which represented 11 serovars and 17 different PFGE types. The most common serovars isolated in NYS were Salmonella enterica serovars Newport, Cerro, and Thompson, while common serovars isolated in SFL were Salmonella serovars Saphra and Newport and S. enterica subsp. diarizonae serovar 50:r:z. High PFGE type diversity (Simpson's diversity index, 0.90 ± 0.02) was observed among Salmonella isolates across both regions; only three PFGE types were shared between the two regions. The probability of three or fewer shared PFGE types was Salmonella isolates were considerably different between the two sampled regions. These findings suggest the potential for PFGE-based source tracking of Salmonella in production environments. PMID:24747908

  4. Seasonal stability of Cladophora-associated Salmonella in Lake Michigan watersheds

    Science.gov (United States)

    Byappanahalli, M.N.; Sawdey, R.; Ishii, S.; Shively, D.A.; Ferguson, J.A.; Whitman, R.L.; Sadowsky, M.J.

    2009-01-01

    The bacterial pathogens Shigella, Salmonella, Campylobacter, and shiga toxin-producing E. coli (STEC) were recently found to be associated with Cladophora growing in southern Lake Michigan. Preliminary results indicated that the Salmonella strains associated with Cladophora were genetically identical to each other. However, because of the small sample size (n = 37 isolates) and a lack of information on spatial-temporal relationships, the nature of the association between Cladophora and Salmonella remained speculative. In this study, we investigated the population structure and genetic relatedness of a large number of Cladophora-borne Salmonella isolates from Lake Michigan (n = 133), as well as those isolated from stream and lake water (n = 31), aquatic plants (n = 8), and beach sands and sediments (n = 8) from adjacent watersheds. Salmonella isolates were collected during 2005-2007 between May and August from Lake Michigan beachsheds in Wisconsin, Illinois, and Indiana. The genetic relatedness of Salmonella isolates was examined by using the horizontal, fluorophore-enhanced rep-PCR (HFERP) DNA fingerprinting technique. While the Salmonella isolates associated with Cladophora exhibited a high degree of genetic relatedness (???92% similarity), the isolates were not all genetically identical. Spatial and temporal relationships were evident in the populations examined, with tight clustering of the isolates both by year and location. These findings suggest that the relationship between Salmonella and Cladophora is likely casual and is related to input sources (e.g. wastewater, runoff, birds) and the predominant Salmonella genotype surviving in the environment during a given season. Our studies indicate that Cladophora is likely an important reservoir for Salmonella and other enteric bacterial pathogens in Lake Michigan beachsheds, which in turn may influence nearshore water quality. ?? 2008 Elsevier Ltd.

  5. Seasonal stability of Cladophora-associated Salmonella in Lake Michigan watersheds.

    Science.gov (United States)

    Byappanahalli, Muruleedhara N; Sawdey, Richard; Ishii, Satoshi; Shively, Dawn A; Ferguson, John A; Whitman, Richard L; Sadowsky, Michael J

    2009-02-01

    The bacterial pathogens Shigella, Salmonella, Campylobacter, and shiga toxin-producing E. coli (STEC) were recently found to be associated with Cladophora growing in southern Lake Michigan. Preliminary results indicated that the Salmonella strains associated with Cladophora were genetically identical to each other. However, because of the small sample size (n=37 isolates) and a lack of information on spatial-temporal relationships, the nature of the association between Cladophora and Salmonella remained speculative. In this study, we investigated the population structure and genetic relatedness of a large number of Cladophora-borne Salmonella isolates from Lake Michigan (n=133), as well as those isolated from stream and lake water (n=31), aquatic plants (n=8), and beach sands and sediments (n=8) from adjacent watersheds. Salmonella isolates were collected during 2005-2007 between May and August from Lake Michigan beachsheds in Wisconsin, Illinois, and Indiana. The genetic relatedness of Salmonella isolates was examined by using the horizontal, fluorophore-enhanced rep-PCR (HFERP) DNA fingerprinting technique. While the Salmonella isolates associated with Cladophora exhibited a high degree of genetic relatedness (>or=92% similarity), the isolates were not all genetically identical. Spatial and temporal relationships were evident in the populations examined, with tight clustering of the isolates both by year and location. These findings suggest that the relationship between Salmonella and Cladophora is likely casual and is related to input sources (e.g. wastewater, runoff, birds) and the predominant Salmonella genotype surviving in the environment during a given season. Our studies indicate that Cladophora is likely an important reservoir for Salmonella and other enteric bacterial pathogens in Lake Michigan beachsheds, which in turn may influence nearshore water quality.

  6. Diffuse abdominal gallium-67 citrate uptake in salmonella infections

    International Nuclear Information System (INIS)

    Garty, I.; Koren, A.

    1987-01-01

    Two pediatric patients with salmonella infections (one with typhoid fever and the second with salmonella C2 gastroenteritis), had a diffuse abdominal uptake of Ga-67 citrate. The possible explanation for this finding is discussed. Salmonella infection should be included as a cause in the differential diagnosis of diffuse accumulation of Ga-67 citrate

  7. Cytoplasmic Copper Detoxification in Salmonella Can Contribute to SodC Metalation but Is Dispensable during Systemic Infection.

    Science.gov (United States)

    Fenlon, Luke A; Slauch, James M

    2017-12-15

    Salmonella enterica serovar Typhimurium is a leading cause of foodborne disease worldwide. Severe infections result from the ability of S Typhimurium to survive within host immune cells, despite being exposed to various host antimicrobial factors. SodCI, a copper-zinc-cofactored superoxide dismutase, is required to defend against phagocytic superoxide. SodCII, an additional periplasmic superoxide dismutase, although produced during infection, does not function in the host. Previous studies suggested that CueP, a periplasmic copper binding protein, facilitates acquisition of copper by SodCII. CopA and GolT, both inner membrane ATPases that pump copper from the cytoplasm to the periplasm, are a source of copper for CueP. Using in vitro SOD assays, we found that SodCI can also utilize CueP to acquire copper. However, both SodCI and SodCII have a significant fraction of activity independent of CueP and cytoplasmic copper export. We utilized a series of mouse competition assays to address the in vivo role of CueP-mediated SodC activation. A copA golT cueP triple mutant was equally as competitive as the wild type, suggesting that sufficient SodCI is active to defend against phagocytic superoxide independent of CueP and cytoplasmic copper export. We also confirmed that a strain containing a modified SodCII, which is capable of complementing a sodCI deletion, was fully virulent in a copA golT cueP background competed against the wild type. These competitions also address the potential impact of cytoplasmic copper toxicity within the phagosome. Our data suggest that Salmonella does not encounter inhibitory concentrations of copper during systemic infection. IMPORTANCE Salmonella is a leading cause of gastrointestinal disease worldwide. In severe cases, Salmonella can cause life-threatening systemic infections, particularly in very young children, the elderly, or people who are immunocompromised. To cause disease, Salmonella must survive the hostile environment inside host

  8. Modeling salmonella Dublin into the dairy herd simulation model Simherd

    DEFF Research Database (Denmark)

    Kudahl, Anne Braad

    2010-01-01

    Infection with Salmonella Dublin in the dairy herd and effects of the infection and relevant control measures are currently being modeled into the dairy herd simulation model called Simherd. The aim is to compare the effects of different control strategies against Salmonella Dublin on both within...... of the simulations will therefore be used for decision support in the national surveillance and eradication program against Salmonella Dublin. Basic structures of the model are programmed and will be presented at the workshop. The model is in a phase of face-validation by a group of Salmonella......-herd- prevalence and economy by simulations. The project Dublin on both within-herd- prevalence and economy by simulations. The project is a part of a larger national project "Salmonella 2007 - 2011" with the main objective to reduce the prevalence of Salmonella Dublin in Danish Dairy herds. Results...

  9. Escitalopram attenuates β-amyloid-induced tau hyperphosphorylation in primary hippocampal neurons through the 5-HT1A receptor mediated Akt/GSK-3β pathway.

    Science.gov (United States)

    Wang, Yan-Juan; Ren, Qing-Guo; Gong, Wei-Gang; Wu, Di; Tang, Xiang; Li, Xiao-Li; Wu, Fang-Fang; Bai, Feng; Xu, Lin; Zhang, Zhi-Jun

    2016-03-22

    Tau hyperphosphorylation is an important pathological feature of Alzheimer's disease (AD). To investigate whether escitalopram could inhibit amyloid-β (Aβ)-induced tau hyperphosphorylation and the underlying mechanisms, we treated the rat primary hippocampal neurons with Aβ1-42 and examined the effect of escitalopram on tau hyperphosphorylation. Results showed that escitalopram decreased Aβ1-42-induced tau hyperphosphorylation. In addition, escitalopram activated the Akt/GSK-3β pathway, and the PI3K inhibitor LY294002 blocked the attenuation of tau hyperphosphorylation induced by escitalopram. Moreover, the 5-HT1A receptor agonist 8-OH-DPAT also activated the Akt/GSK-3β pathway and decreased Aβ1-42-induced tau hyperphosphorylation. Furthermore, the 5-HT1A receptor antagonist WAY-100635 blocked the activation of Akt/GSK-3β pathway and the attenuation of tau hyperphosphorylation induced by escitalopram. Finally, escitalopram improved Aβ1-42 induced impairment of neurite outgrowth and spine density, and reversed Aβ1-42 induced reduction of synaptic proteins. Our results demonstrated that escitalopram attenuated Aβ1-42-induced tau hyperphosphorylation in primary hippocampal neurons through the 5-HT1A receptor mediated Akt/GSK-3β pathway.

  10. The occurrence of Salmonella in airline meals.

    Science.gov (United States)

    Hatakka, M; Asplund, K

    1993-01-01

    The occurrence of Salmonella in airline meals was studied in 1989-1992. Samples were collected from flight kitchens in 29 countries. The material consisted of 400 cold dishes and 1,288 hot dishes as well as salads, cheese plates and deserts. Total number of samples was 2211. Salmonella spp. were isolated from 6 samples; 1 contaminated sample was a cold dish prepared in Bangkok, 1 was a hot dish prepared in Mombasa and the remaining 4 contaminated samples were hot dishes prepared within one week in Beijing. The isolated serotypes were S. ohio, S. manchester and S. braenderup. The contaminated cold dish prepared by a flight kitchen in Bangkok was found to be connected with a Salmonella outbreak which occurred in Finland in 1990. Cold airline dishes containing food of animal origin seems to be more risky as a source of Salmonella infections among airline passengers.

  11. Aptamer-based viability impedimetric sensor for bacteria.

    Science.gov (United States)

    Labib, Mahmoud; Zamay, Anna S; Kolovskaya, Olga S; Reshetneva, Irina T; Zamay, Galina S; Kibbee, Richard J; Sattar, Syed A; Zamay, Tatiana N; Berezovski, Maxim V

    2012-11-06

    The development of an aptamer-based viability impedimetric sensor for bacteria (AptaVISens-B) is presented. Highly specific DNA aptamers to live Salmonella typhimurium were selected via the cell-systematic evolution of ligands by exponential enrichment (SELEX) technique. Twelve rounds of selection were performed; each comprises a positive selection step against viable S. typhimurium and a negative selection step against heat killed S. typhimurium and a mixture of related pathogens, including Salmonella enteritidis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Citrobacter freundii to ensure the species specificity of the selected aptamers. The DNA sequence showing the highest binding affinity to the bacteria was further integrated into an impedimetric sensor via self-assembly onto a gold nanoparticle-modified screen-printed carbon electrode (GNP-SPCE). Remarkably, this aptasensor is highly selective and can successfully detect S. typhimurium down to 600 CFU mL(-1) (equivalent to 18 live cells in 30 μL of assay volume) and distinguish it from other Salmonella species, including S. enteritidis and S. choleraesuis. This report is envisaged to open a new venue for the aptamer-based viability sensing of a variety of microorganisms, particularly viable but nonculturable (VBNC) bacteria, using a rapid, economic, and label-free electrochemical platform.

  12. Discovery of Salmonella Virulence Factors Translocated via Outer Membrane Vesicles to Murine Macrophages.

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hyunjin; Ansong, Charles; Adkins, Joshua N.; Heffron, Fred

    2011-06-01

    We have previously shown that the regulators SpvR, FruR, IHF, PhoP/PhoQ, SsrA/SsrB, SlyA, Hnr, RpoE, SmpB, CsrA, RpoS, Crp, OmpR/EnvZ, and Hfq are essential for Salmonella Typhimurium virulence in mice. Here we use quantitative LC-MS-based proteomics profiling of in-frame deletion mutants of these 14 regulators to identify proteins that are coordinately regulated by these virulence regulators and are thus presumably novel factors contributing to Salmonella pathogenesis. Putative candidate proteins from proteomics analysis were determined, which exhibited similar abundance profiles to those of Salmonella pathogenicity island (SPI)-2 type III secretion system (TTSS) proteins. A subset of 5 proteins including STM0082, STM1548, PdgL, STM1633, and STM3595 was selected for further analysis. All 5 proteins were expressed inside macrophage cells and STM0082 (SrfN) was secreted into host cytoplasm. Furthermore, deletion of STM0082 attenuated virulence in mice when administered intraperitoneally as determined by competitive index. srfN transcription was positively regulated by SsrAB, however, secretion was independent of SPI-2 TTSS as well as SPI-1 TTSS and flagella. Proteins including PagK and STM2585A, which are positively regulated by PhoP/PhoQ, have sec signal peptides as predicted for SrfN and were secreted into macrophage cytoplasm regardless of SPI-2 TTSS. Isolation of outer membrane vesicles (OMVs) revealed the presence of SrfN, PagK, and STM2585A inside vesicle compartments. This result is the first case showing delivery of virulence effectors via OMVs in S. Typhimurium. Moreover, Hfq regulation of SrfN translation suggests that small non-coding RNAs may be responsible for regulating effector protein expression.

  13. 75 FR 48973 - Draft Guidance for Industry: Prevention of Salmonella

    Science.gov (United States)

    2010-08-12

    ...] Draft Guidance for Industry: Prevention of Salmonella Enteritidis in Shell Eggs During Production... entitled ``Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and... on how to comply with certain provisions contained in FDA's final rule ``Prevention of Salmonella...

  14. Anti-tumoral effect of the mitochondrial target domain of Noxa delivered by an engineered Salmonella typhimurium.

    Directory of Open Access Journals (Sweden)

    Jae-Ho Jeong

    Full Text Available Bacterial cancer therapy relies on the fact that several bacterial species are capable of targeting tumor tissue and that bacteria can be genetically engineered to selectively deliver therapeutic proteins of interest to the targeted tumors. However, the challenge of bacterial cancer therapy is the release of the therapeutic proteins from the bacteria and entry of the proteins into tumor cells. This study employed an attenuated Salmonella typhimurium to selectively deliver the mitochondrial targeting domain of Noxa (MTD as a potential therapeutic cargo protein, and examined its anti-cancer effect. To release MTD from the bacteria, a novel bacterial lysis system of phage origin was deployed. To facilitate the entry of MTD into the tumor cells, the MTD was fused to DS4.3, a novel cell-penetrating peptide (CPP derived from a voltage-gated potassium channel (Kv2.1. The gene encoding DS4.3-MTD and the phage lysis genes were placed under the control of PBAD , a promoter activated by L-arabinose. We demonstrated that DS4.3-MTD chimeric molecules expressed by the Salmonellae were anti-tumoral in cultured tumor cells and in mice with CT26 colon carcinoma.

  15. Curcumin Attenuates Staurosporine-Mediated Death of Retinal Ganglion Cells

    OpenAIRE

    Burugula, Balabharathi; Ganesh, Bhagyalaxmi S.; Chintala, Shravan K.

    2011-01-01

    The functional effect of curcumin, a free radical scavenger and an herbal medicine from Indian yellow curry spice, Curcuma longa, on protease-mediated retinal ganglion cell death was investigated. These results show, for the first time, that curcumin indeed prevents the protease-mediated death of RGCs, both in vitro and in vivo.

  16. Pleural Empyema due to Group D Salmonella

    Directory of Open Access Journals (Sweden)

    Jennifer C. Kam

    2012-01-01

    Full Text Available Non-typhi Salmonella normally presents as a bacteremia, enterocolitis, and endovascular infection but rarely manifests as pleuropulmonary disease. We present a case of a 66-year-old female with underlying pulmonary pathology, secondary to an extensive smoking history, who presented with a left-sided pleural effusion. The causative agent was identified as being group D Salmonella. Decortication of the lung was performed and the patient was discharged on antibiotics with resolution of her symptoms. This case helps to support the inclusion of Salmonella group D as a possible etiological agent of infection in the differential causes of exudative pleural effusions.

  17. Survey of Salmonella contamination in chicken layer farms in three Caribbean countries.

    Science.gov (United States)

    Adesiyun, Abiodun; Webb, Lloyd; Musai, Lisa; Louison, Bowen; Joseph, George; Stewart-Johnson, Alva; Samlal, Sannandan; Rodrigo, Shelly

    2014-09-01

    This study was conducted to investigate the demography, management, and production practices on layer chicken farms in Trinidad and Tobago, Grenada, and St. Lucia and the frequency of risk factors for Salmonella infection. The frequency of isolation of Salmonella from the layer farm environment, eggs, feeds, hatchery, and imported day-old chicks was determined using standard methods. Of the eight risk factors (farm size, age group of layers, source of day-old chicks, vaccination, sanitation practices, biosecurity measures, presence of pests, and previous disease outbreaks) for Salmonella infection investigated, farm size was the only risk factor significantly associated (P = 0.031) with the prevalence of Salmonella; 77.8% of large farms were positive for this pathogen compared with 33.3 and 26.1% of medium and small farms, respectively. The overall isolation rate of Salmonella from 35 layer farms was 40.0%. Salmonella was isolated at a significantly higher rate (P hatcheries, and airports in this country were negative. Salmonella Anatum, Salmonella group C, and Salmonella Kentucky were the predominant serotypes in Trinidad and Tobago, Grenada, and St. Lucia, respectively. Although Salmonella infections were found in layer birds sampled, table eggs appear to pose minimal risk to consumers. However, the detection of Salmonella -contaminated farm environments and feeds cannot be ignored. Only 2.9% of the isolates belonged to Salmonella Enteritidis, a finding that may reflect the impact of changes in farm management and poultry production in the region.

  18. Salmonella infection acquired from reptilian pets.

    Science.gov (United States)

    Sanyal, D; Douglas, T; Roberts, R

    1997-10-01

    Two children presented with signs and symptoms of gastroenteritis. Salmonella chameleon was isolated from the stool of one child and also from an iguana kept in the home as a pet. Salmonella arizonae was isolated from the stool of the other child and also from four snakes sharing the same household. Exotic reptiles are unsuitable pets to share the home environment with infants.

  19. Samsung Salmonella Detection Kit. AOAC Performance Tested Method(SM) 021203.

    Science.gov (United States)

    Li, Jun; Cheung, Win Den; Opdyke, Jason; Harvey, John; Chong, Songchun; Moon, Cheol Gon

    2012-01-01

    Salmonella, one of the most common causes of foodborne illness, is a significant public health concern worldwide. There is a need in the food industry for methods that are simple, rapid, and sensitive for the detection of foodborne pathogens. In this study, the Samsung Salmonella Detection Kit, a real-time PCR assay for the detection of Salmonella, was evaluated according to the current AOAC guidelines. The validation consisted of lot-to-lot consistency, stability, robustness, and inclusivity/exclusivity studies, as well as a method comparison of 10 different food matrixes. In the validation, the Samsung Salmonella Detection Kit was used in conjunction with the Applied Biosystems StepOnePlus PCR system and the Samsung Food Testing Software for the detection of Salmonella species. The performance of the assays was compared to the U.S. Department of Agriculture/Food Safety and Inspection Service-Microbiology Laboratory Guidebook (USDA/FSIS-MLG) 4.05: Isolation and Identification of Salmonella from Meat, Poultry, Pasteurized Egg, and Catfish and the and U.S. Food and Drug Administration/Bacteriological Analytical Manual (FDA/BAM) Chapter 5 Salmonella reference methods. The validation was conducted using an unpaired study design for detection of Salmonella spp. in raw ground beef, raw pork, raw ground pork, raw chicken wings, raw salmon, alfalfa sprouts, pasteurized orange juice, peanut butter, pasteurized whole milk, and shell eggs. The Samsung Salmonella Detection Kit demonstrated lot-to-lot consistency among three independent lots as well as ruggedness with minor modifications to changes in enrichment incubation time, enrichment incubation temperature, and DNA sample volume for PCR reaction. Stability was observed for 13 months at -20 degrees C and 3 months at 5 degrees C. For the inclusivity/exclusivity study, the Samsung Salmonella Detection Kit correctly identified 147 Salmonella species isolates out of 147 isolates tested from each of three different enrichment

  20. Cross contamination of turkey carcasses by Salmonella species during defeathering.

    Science.gov (United States)

    Nde, C W; McEvoy, J M; Sherwood, J S; Logue, C M

    2007-01-01

    Salmonella present on the feathers of live birds could be a source of contamination to carcass skin during defeathering. In this study, the possibility of transfer of Salmonella from the feathers of live turkeys to carcass tissue during the defeathering process at a commercial turkey processing plant was investigated. The contribution of scald water and the fingers of the picker machines to cross contamination were also examined. Over 4 visits, swab samples were collected from 174 randomly selected tagged birds before and after defeathering. Two swab samples from the fingers of the picker machines and a sample of scald water were also collected during each visit. Detection of Salmonella was carried out following standard cultural and identification methods. The DNA fingerprints obtained from pulsed field gel electrophoresis of Salmonella serotypes isolated before and after defeathering, from scald water, and from the fingers of the picker machines were compared to trace cross contamination routes. Salmonella prevalence was similar before and after defeathering during visits 2 and 3 and significantly increased after defeathering during visits 1 and 4. Over the 4 visits, all Salmonella subtypes obtained after defeathering were also isolated before defeathering. The results of this study suggest that Salmonella was transferred from the feathers to carcass skin during each visit. On each visit, the Salmonella subtypes isolated from the fingers of the picker machines were similar to subtypes isolated before and after defeathering, indicating that the fingers facilitate carcass cross contamination during defeathering. Salmonella isolated from scald water during visit 4 was related to isolates obtained before and after defeathering, suggesting that scald water is also a vehicle for cross contamination during defeathering. By using molecular subtyping, this study demonstrated the relationship between Salmonella present on the feathers of live turkeys and carcass skin after

  1. UV light-induced mutability in Salmonella strains containing the umuDC or the mucAB operon

    International Nuclear Information System (INIS)

    Herrera, G.; Urios, A.; Aleixandre, V.; Blanco, M.

    1988-01-01

    Multicopy plasmids carrying either the umuDC operon of Escherichia coli or its analog mucAB operon, were introduced into Ames Salmonella strains in order to analyze the influence of UmuDC and MucAB proteins on repair and mutability after UV irradiation. It was found that in uvr + bacteria, plasmid pICV80:mucAB increased the frequency of UV-induced His + revertants whereas pSE117:umuDC caused a smaller increase in UV mutagenesis. In ΔuvrB bacteria, the protective role of pSE117 against UV killing was weak, and there was a great reduction in the mutant yield. In contrast, in these cells, pICV80 led to a large increase in both cell survival and mutation frequency. These results suggest that in Salmonella, as in E. coli, MucAB proteins mediate UV mutagenesis more efficiently than UmuDC proteins do. Plasmid pICV84:umuD + C - significantly increased UV mutagenesis of TA2659:ΔuvrB cells whereas in them, pICV77:mucA + B - had no effect on mutability indicating the presence in Salmonella TA2659 of a gene functionally homologous to umuC. 18 refs.; 1 figure; 3 tabs

  2. Case report of Salmonella cross-contamination in a food laboratory.

    Science.gov (United States)

    Rasschaert, Geertrui; De Reu, K; Heyndrickx, M; Herman, L

    2016-03-10

    This paper describes a case of Salmonella cross-contamination in a food laboratory. In 2012, chocolate bars shipped from Belgium to the USA were prevented from entering the USA because a Salmonella Rissen strain had been isolated from one of the chocolate bars in a Belgian food laboratory. However, a retrospective study of the Salmonella isolates sent from the laboratory to the Belgian National Reference Laboratory for Salmonella revealed that 7 weeks prior, a Salmonella Rissen strain has been isolated from fish meal in the same food laboratory. The chocolate bars were not expected to be contaminated with Salmonella because the ingredients all tested negative during the production process. Furthermore, because Salmonella Rissen is only rarely isolated from food, it was hypothesized that the two Salmonella Rissen isolates belonged to the same strain and that the second isolation event in this laboratory was caused by cross-contamination. To confirm this hypothesis, both Salmonella Rissen isolates were fingerprinted using different molecular techniques. To evaluate the discriminatory power of the techniques used, 11 other Salmonella Rissen isolates from different origins were included in the comparison. Pulsed-field gel electrophoresis, repetitive element palindromic PCR and three random amplified polymorphic DNA PCR assays were used. Repetitive element palindromic PCR and random amplified polymorphic DNA PCR assays were insufficiently discriminatory, whereas pulsed-field gel electrophoresis using the combination of two restriction enzymes showed sufficient discrimination to confirm the hypothesis. Although cross-contamination in food laboratories are rarely reported, cross-contamination can always occur. Laboratories should therefore always be aware of the possibility of cross-contamination, especially when enrichment is used in the microbiological analysis. Furthermore, it is advised that results showing isolates of the same serotype isolated in a short time frame

  3. Fate of Salmonella throughout Production and Refrigerated Storage of Tahini.

    Science.gov (United States)

    Zhang, Yangjunna; Keller, Susanne E; Grasso-Kelley, Elizabeth M

    2017-06-01

    Tahini, a low-moisture food that is made from sesame seeds, has been implicated in outbreaks of salmonellosis. In this study, the fate of Salmonella was determined through an entire process for the manufacture of tahini, including a 24-h seed soaking period before roasting, subsequent grinding, and storage at refrigeration temperature. Salmonella populations increased by more than 3 log CFU/g during a 24-h soaking period, reaching more than 7 log CFU/g. Survival of Salmonella during roasting at three temperatures, 95, 110, and 130°C, was assessed using seeds on which Salmonella was grown. Salmonella survival was impacted both by temperature and the water activity (a w ) at the beginning of the roasting period. When roasted at 130°C with a high initial a w (≥0.90) and starting Salmonella populations of ∼8.5 log CFU/g, populations quickly decreased below detection limits within the first 10 min. However, when the seeds were reduced to an a w of 0.45 before roasting at the same temperature, 3.5 log CFU/g remained on the seeds after 60 min. In subsequent storage studies, seeds were roasted at 130°C for 15 min before processing into tahini. For the storage studies, tahini was inoculated using two methods. The first method used seeds on which Salmonella was first grown before roasting. In the second method, Salmonella was inoculated into the tahini after manufacture. All tahini was stored for 119 days at 4°C. No change in Salmonella populations was recorded for tahini throughout the entire 119 days regardless of the inoculation method used. These combined results indicate the critical importance of a w during a roasting step during tahini manufacture. Salmonella that survive roasting will likely remain viable throughout the normal shelf life of tahini.

  4. Plant-mediated restriction of Salmonella enterica on tomato and spinach leaves colonized with Pseudomonas plant growth-promoting rhizobacteria.

    Science.gov (United States)

    Hsu, Chiun-Kang; Micallef, Shirley A

    2017-10-16

    Reducing Salmonella enterica association with plants during crop production could reduce risks of fresh produce-borne salmonellosis. Plant growth-promoting rhizobacteria (PGPR) colonizing plant roots are capable of promoting plant growth and boosting resistance to disease, but the effects of PGPR on human pathogen-plant associations are not known. Two root-colonizing Pseudomonas strains S2 and S4 were investigated in spinach, lettuce and tomato for their plant growth-promoting properties and their influence on leaf populations of S. enterica serovar Newport. Plant roots were inoculated with Pseudomonas in the seedling stage. At four (tomato) and six (spinach and lettuce) weeks post-germination, plant growth promotion was assessed by shoot dry weight (SDW) and leaf chlorophyll content measurements. Leaf populations of S. Newport were measured after 24h of leaf inoculation with this pathogen by direct plate counts on Tryptic Soy Agar. Root inoculation of spinach cv. 'Tyee', with Pseudomonas strain S2 or S4 resulted in a 69% and 63% increase in SDW compared to non-inoculated controls (pgrowth by over 40% compared to controls (pgrowth promotion was detected in tomato cv. 'BHN602', but S2-inoculated plants had elevated leaf chlorophyll content (13%, pgrowth, but also reduce the fitness of epiphytic S. enterica in the phyllosphere. Plant-mediated effects induced by PGPR may be an effective strategy to minimize contamination of crops with S. enterica during cultivation. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Prevalence and antimicrobial profiles of Salmonella serovars from ...

    African Journals Online (AJOL)

    ADEYEYE

    2014-01-21

    Jan 21, 2014 ... Presumptive Salmonella isolates were determined by using the conventional ... Salmonella represents a major contaminant of vegetables consumed in Maiduguri, North-eastern ... serovars in vegetables in Nigeria do not exist.

  6. Case Report: Salmonella lung infection | Ohanu | International ...

    African Journals Online (AJOL)

    A case of an 84 year old man admitted because of fever, abdominal discomfort, weakness, past history of cough wheezing and abuse of prednisolone and Erythromycin. He had Bronchopneumonia and diabetes. Salmonella typhimurium was isolated from both his sputum and blood while stool was negative for salmonella.

  7. Swiss Army Pathogen: The Salmonella Entry Toolkit

    Directory of Open Access Journals (Sweden)

    Peter J. Hume

    2017-08-01

    Full Text Available Salmonella causes disease in humans and animals ranging from mild self-limiting gastroenteritis to potentially life-threatening typhoid fever. Salmonellosis remains a considerable cause of morbidity and mortality globally, and hence imposes a huge socio-economic burden worldwide. A key property of all pathogenic Salmonella strains is the ability to invade non-phagocytic host cells. The major determinant of this invasiveness is a Type 3 Secretion System (T3SS, a molecular syringe that injects virulence effector proteins directly into target host cells. These effectors cooperatively manipulate multiple host cell signaling pathways to drive pathogen internalization. Salmonella does not only rely on these injected effectors, but also uses several other T3SS-independent mechanisms to gain entry into host cells. This review summarizes our current understanding of the methods used by Salmonella for cell invasion, with a focus on the host signaling networks that must be coordinately exploited for the pathogen to achieve its goal.

  8. Radiosensitivity study of salmonella enteritidis in chickens

    International Nuclear Information System (INIS)

    Fernandez Gianotti, Tomas

    1997-01-01

    One of the applications of ionizing radiations in food is the inactivation of vegetative phatogenic bacteria (radicidation) such as Salmonella, Shigella, Campylobacter, Vibro and Listeria. These bacteria are associated with the diseases transmitted by food (ETA). Fresh and frozen farmyard fowls can be contaminated with pathogenic microorganisms, between them Salmonella. In Argentine, between years 1987-1990, Salmonella enteritidis was the main cause of salmonellosis. In food irradiation, with the aim of improving and assuring its hygienic quality, it is important to know the radiosensitivity of microorganisms to be inactivated. Inactivation of a determined microorganism shall depend, between others factors, of the species, strain, number and of the irradiation conditions (temperature, media, etc.). D 10 value is a very useful data in order to compare radiosensitivities between the microorganisms and the influence of different factors in their sensitivities. In this paper, it was determined the sensitivity to the gamma radiation of Salmonella enteritidis in fresh and frozen chickens

  9. Salmonellae in avian wildlife in Norway from 1969 to 2000

    DEFF Research Database (Denmark)

    Refsum, T.; Handeland, K.; Baggesen, Dorte Lau

    2002-01-01

    Postmortem records of wild-living birds in Norway with laboratory-confirmed findings of salmonella infection were summarized for the period from 1969 to 2000. Salmonella spp. were isolated from 470 birds belonging to 26 species. The salmonella-positive birds included 441 small passerines, 15 gull...

  10. Current antimicrobial sensitivity pattern of typhoidal salmonellae in a referral diagnostic centre

    Directory of Open Access Journals (Sweden)

    Umer Shujat

    2016-03-01

    Full Text Available Background: Infections caused by typhoidal salmonellae are an important public health concern in Pakistan. Inappropriate and injudicious use of fluoroquinolones has reduced their efficacy due to development of high level resistance. Aim: To ascertain the current susceptibility pattern of typhoidal salmonellae thus guiding the physicians for better management of typhoid patients.Materials and Methods: A study was conducted at our institution from January 2012 through December 2013 to investigate current susceptibility pattern of typhoidal salmonellae. Results: Out of 200 isolates, 107 (53.5% were identified as Salmonella Typhi and 93 (46.5% as Salmonella Paratyphi A. Sensitivities of Salmonella Typhi were as follows: ampicillin (48.6%, chloramphenicol (45.8%, co-trimoxazole (40.1%, ciprofloxacin (11.2%. Sensitivities of Salmonella Paratyphi A were: ampicillin (80.6%, chloramphenicol (89.2%, co-trimoxazole (90.3%, and ciprofloxacin (16.1%. No resistance was detected against third generation cephalosporins. Conclusions: Typhoidal salmonellae are still entirely susceptible to third generation cephalosporins in our setting. Marked rise in resistance to fluoroquinolones has reduced their empirical usage. Sensitivity of Salmonella Paratyphi A to conventional antityphoid drugs was encouraging.

  11. Salmonella detection in a microfluidic channel using orbiting magnetic beads

    Science.gov (United States)

    Ballard, Matt; Mills, Zachary; Owen, Drew; Hanasoge, Srinivas; Hesketh, Peter; Alexeev, Alexander

    2015-03-01

    We use three-dimensional simulations to model the detection of salmonella in a complex fluid sample in a microfluidic channel. Salmonella is captured using magnetic microbeads orbiting around soft ferromagnetic discs at the microchannel bottom subjected to a rotating external magnetic field. Numerical simulations are used to model the dynamics of salmonella and microbeads throughout the detection process. We examine the effect of the channel geometry on the salmonella capture, and the forces applied to the salmonella as it is dragged through the fluid after capture. Our findings guide the design of a lab-on-a-chip device to be used for detection of salmonella in food samples in a way that ensures that salmonella captured by orbiting microbeads are preserved until they can be extracted from the system for testing, and are not washed away by the fluid flow or damaged due to the experience of excessive stresses. Such a device is needed to detect bacteria at the food source and prevention of consumption of contaminated food, and also can be used for the detection of a variety of biomaterials of interest from complex fluid samples. Support from USDA and NSF is gratefully acknowledged.

  12. From Exit to Entry: Long-term Survival and Transmission of Salmonella

    Directory of Open Access Journals (Sweden)

    Landon L. Waldner

    2012-10-01

    Full Text Available Salmonella spp. are a leading cause of human infectious disease worldwide and pose a serious health concern. While we have an improving understanding of pathogenesis and the host-pathogen interactions underlying the infection process, comparatively little is known about the survival of pathogenic Salmonella outside their hosts. This review focuses on three areas: (1 in vitro evidence that Salmonella spp. can survive for long periods of time under harsh conditions; (2 observations and conclusions about Salmonella persistence obtained from human outbreaks; and (3 new information revealed by genomic- and population-based studies of Salmonella and related enteric pathogens. We highlight the mechanisms of Salmonella persistence and transmission as an essential part of their lifecycle and a prerequisite for their evolutionary success as human pathogens.

  13. Antibiotic susceptibilities of Salmonella species prevalent among ...

    African Journals Online (AJOL)

    This study was conducted to assess the prevalence of Salmonella species among children having diarrhea in Katsina State, Nigeria. A total of 220 diarrhea stool samples of children aged five years and below (0-5 years) were collected and screened for Salmonella species using culture technique. Presumptively positive ...

  14. Salmonella in the lairage of pig slaughterhouses

    NARCIS (Netherlands)

    Swanenburg, M.; Urlings, H.A.P.; Keuzenkamp, D.A.; Snijders, J.M.A.

    2001-01-01

    The purpose of this study was to determine if lairages of pig slaughterhouses can act as a source of contamination of slaughtered pigs with Salmonella. The prevalence and variety of serotypes of Salmonella in the lairages of two pig slaughterhouses were determined, and the efficacy of the usual

  15. Detection of Salmonella typhi agglutinins in sera of patients with ...

    African Journals Online (AJOL)

    Background and Purpose: Widal test is frequently applied for the detection of Salmonella agglutinins to diagnose Salmonella enterica serotype Typhi infection. There are however a number of controversies challenging the diagnostic utility of this test. This study was performed to determine the prevalence of Salmonella ...

  16. The epidemiology of Salmonella infection of calves: the role of dealers.

    Science.gov (United States)

    Wray, C.; Todd, N.; McLaren, I.; Beedell, Y.; Rowe, B.

    1990-01-01

    Salmonellas were detected in the environment of 10 of the 12 calf dealers' premises studied. The cleaning and disinfection routines were often ineffective and salmonellas were isolated from 7.6% and 5.3% of the wall and floor samples before disinfection and 6.8% and 7.6% afterwards. Eight different salmonella serotypes were detected, of which the commonest were Salmonella typhimurium, predominantly phage type DT204C, and S. dublin. Plasmid profiles were used to fingerprint S. typhimurium DT204C and the results indicated that with the exception of one of the premises, prolonged salmonella-persistence in the environment was not occurring. Three separate epidemics of salmonellosis in calves were studied by use of plasmid profile analysis. The results illustrated the role of delers, and their subcontractors, in the dissemination of salmonellas. The study concludes with suggestions for methods to reduce the spread of salmonellas in the calf marketing chain. PMID:2209734

  17. Persistence of a Salmonella enterica serovar typhimurium DT12 clone in a piggery and in agricultural soil amended with Salmonella-contaminated slurry

    DEFF Research Database (Denmark)

    Baloda, Suraj B.; Christensen, Lise; Trajcevska, Silvija

    2001-01-01

    Prevalence of Salmonella enterica on a Danish pig farm presenting recurrent infections was investigated. A comparison of the pulsed-held gel electrophoresis patterns of fecal isolates from piggeries, waste slurry, and agricultural soil amended with Salmonella-contaminated animal waste (slurry......) and subclinical isolates from the same farm (collected in 1996 and later) showed identical patterns, indicating long-term persistence of the Salmonella enterica serovar Typhimurium DT12 clone in the herd environment. Furthermore, when Salmonella-contaminated slurry was disposed of on the agricultural soil (a...... common waste disposal practice), the pathogen was isolated up to 14 days after the spread, indicating potentially high risks of transmission of the pathogen in the environment, animals, and humans....

  18. In vitro selection of RNA aptamer specific to Salmonella typhimurium.

    Science.gov (United States)

    Han, Seung Ryul; Lee, Seong-Wook

    2013-06-28

    Salmonella is a major foodborne pathogen that causes a variety of human diseases. Development of ligands directly and specifically binding to the Salmonella will be crucial for the rapid detection of, and thus for efficient protection from, the virulent bacteria. In this study, we identified a RNA aptamer-based ligand that can specifically recognize Salmonella Typhimurium through SELEX technology. To this end, we isolated and characterized an RNase-resistant RNA aptamer that bound to the OmpC protein of Salmonella Typhimurium with high specificity and affinity (Kd ~ 20 nM). Of note, the selected aptamer was found to specifically bind to Salmonella Typhimurium, but neither to Gram-positive bacteria (Staphylococcus aureus) nor to other Gram-negative bacteria (Escherichia coli O157:H7). This was evinced by aptamer-immobilized ELISA and aptamer-linked precipitation experiments. This Salmonella species-specific aptamer could be useful as a diagnostic ligand against pathogen-caused foodborne sickness.

  19. In vitro study of the effects of ultrasound-mediated glycerol on optical attenuation of human normal and cancerous esophageal tissues with optical coherence tomography

    International Nuclear Information System (INIS)

    Zhang, Y Q; Wei, H J; Guo, Z Y; Gu, H M; Guo, X; Zhu, Z G; Yang, H Q; Xie, S S

    2013-01-01

    Previous studies from our group have demonstrated that glucose solution can induce optical clearing enhancement of esophageal tissues with optical coherence tomography (OCT). The aims of this study were to evaluate the optical clearing effects of ultrasound-mediated optical clearing agents (OCAs) and to find more effective methods to distinguish human normal esophageal tissues (NE) and cancerous esophageal tissues (CE). Here we used the OCT technique to investigate the optical attenuation of NE and CE in vitro after treatment with 30% glycerol alone and glycerol combined with ultrasound, respectively. Experimental results showed that the averaged attenuation coefficient of CE was significantly larger than that of NE. The maximal decreases of averaged attenuation coefficients of NE and CE were approximately 48.7% and 36.2% after treatment with 30% glycerol alone, and they were significantly lower than those treated with 30% glycerol and ultrasound (57.5% in NE and 44.8% in CE). Moreover, after treatment with 30% glycerol alone, the averaged attenuation coefficients of NE and CE reached their minima in about 80 min and 65 min, respectively. The times were much shorter in NE and CE after treatment with glycerol with ultrasound, being about 62 min and 50 min, respectively. The results suggest that there is a significant difference in the optical properties of NE and CE, and that OCT with an ultrasound–OCAs combination has the ability to distinguish CE from NE. (paper)

  20. Sinomenine attenuates renal fibrosis through Nrf2-mediated inhibition of oxidative stress and TGFβ signaling

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Tian [School of Life Science & Technology, China Pharmaceutical University, Nanjing 210009 (China); Yin, Shasha; Yang, Jun; Zhang, Qin; Liu, Yangyang [Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing 210093 (China); Huang, Fengjie, E-mail: hfj@cpu.edu.cn [School of Life Science & Technology, China Pharmaceutical University, Nanjing 210009 (China); Cao, Wangsen, E-mail: wangsencao@nju.edu.cn [Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing 210093 (China)

    2016-08-01

    Renal fibrosis is the common feature of chronic kidney disease and mainly mediated by TGFβ-associated pro-fibrogenic signaling, which causes excessive extracellular matrix accumulation and successive loss of kidney functions. Sinomenine (SIN), an alkaloid derived from medicinal herb extensively used in treatment of rheumatoid arthritis and various inflammatory disorders, displays renal protective properties in experimental animals; however its pharmacological potency against renal fibrosis is not explored. In this study we report that SIN possesses strong anti-renal fibrosis functions in kidney cell and in mouse fibrotic kidney. SIN beneficially modulated the pro-fibrogenic protein expression in TGFβ-treated kidney cells and attenuated the renal fibrotic pathogenesis incurred by unilateral ureteral obstruction (UUO), which correlated with its activation of Nrf2 signaling - the key defender against oxidative stress with anti-fibrotic potentials. Further investigation on its regulation of Nrf2 downstream events revealed that SIN significantly balanced oxidative stress via improving the expression and activity of anti-oxidant and detoxifying enzymes, and interrupted the pro-fibrogenic signaling of TGFβ/Smad and Wnt/β-catenin. Even more impressively SIN achieved its anti-fibrotic activities in an Nrf2-dependent manner, suggesting that SIN regulation of Nrf2-associated anti-fibrotic activities constitutes a critical component of SIN's renoprotective functions. Collectively our studies have demonstrated a novel anti-fibrotic property of SIN and its upstream events and provided a molecular basis for SIN's potential applications in treatment of renal fibrosis-associated kidney disorders. - Highlights: • Sinomenine has strong potency of inhibiting renal fibrosis in UUO mouse kidney. • Sinomenine attenuates the expression of profibrogenic proteins. • Sinomenine balances renal fibrosis-associated oxidative stress. • Sinomenine mitigates profibrogenic

  1. Prevalence and antimicrobial susceptibility of salmonellae isolates from reptiles in Taiwan.

    Science.gov (United States)

    Chen, Chun-Yu; Chen, Wan-Ching; Chin, Shih-Chien; Lai, Yen-Hsueh; Tung, Kwong-Chung; Chiou, Chien-Shun; Hsu, Yuan-Man; Chang, Chao-Chin

    2010-01-01

    Pets, including reptiles, have been shown to be a source of Salmonella infection in humans. Due to increasing popularity and variety of exotic reptiles as pets in recent years, more human clinical cases of reptile-associated Salmonella infection have been identified. However, limited information is available with regard to serotypes in different reptiles (turtles, snakes, and lizards) and antimicrobial resistance of Salmonella in pet reptiles. The current study was thus conducted to determine the prevalence of Salmonella colonization in pet reptiles. Salmonella organisms were isolated from 30.9% of 476 reptiles investigated. The isolation prevalences were 69.7% (23/33), 62.8% (27/43), and 24.3% (97/400) in snakes, lizards, and turtles, respectively. A total of 44 different Salmonella serovars were identified. Compared with S. Heron, Bredeney, Treforest, and 4,[5],12:i:-, S. Typhimurium isolates were resistant to many antimicrobials tested, and notably 61.1% of the isolates were resistant to cephalothin. The results indicated that raising reptiles as pets could be a possible source of Salmonella infection in humans, particularly zoonotic Salmonella serovars such as S. Typhimurium that may be resistant to antimicrobials.

  2. Salmonella in Wastes Produced at Commercial Poultry Farms1

    Science.gov (United States)

    Kraft, D. J.; Olechowski-Gerhardt, Carolyn; Berkowitz, J.; Finstein, M. S.

    1969-01-01

    Composite samples of freshly voided excreta from 91 poultry houses were tested qualitatively for Salmonella; 26 (29%) were positive. The houses were located on 36 farms, 18 of which (50%) yielded one or more positive samples. In a separate, quantitative study, Salmonella densities ranged from less than 1 to over 34,000 per g of excreta (dry weight). High densities were noted in waste from cage houses, but not in waste from floor houses (litter or wire floors). Salmonella-shedding chickens were located in only one small area of the row of cages examined in detail. A total of 15 Salmonella serotypes were identified during the study. PMID:5370457

  3. Survival and Filamentation of Salmonella enterica Serovar Enteritidis PT4 and Salmonella enterica Serovar Typhimurium DT104 at Low Water Activity

    Science.gov (United States)

    Mattick, K. L.; Jørgensen, F.; Legan, J. D.; Cole, M. B.; Porter, J.; Lappin-Scott, H. M.; Humphrey, T. J.

    2000-01-01

    In this study we investigated the long-term survival of and morphological changes in Salmonella strains at low water activity (aw). Salmonella enterica serovar Enteritidis PT4 and Salmonella enterica serovar Typhimurium DT104 survived at low aw for long periods, but minimum humectant concentrations of 8% NaCl (aw, 0.95), 96% sucrose (aw, 0.94), and 32% glycerol (aw, 0.92) were bactericidal under most conditions. Salmonella rpoS mutants were usually more sensitive to bactericidal levels of NaCl, sucrose, and glycerol. At a lethal aw, incubation at 37°C resulted in more rapid loss of viability than incubation at 21°C. At aw values of 0.93 to 0.98, strains of S. enterica serovar Enteritidis and S. enterica serovar Typhimurium formed filaments, some of which were at least 200 μm long. Filamentation was independent of rpoS expression. When the preparations were returned to high-aw conditions, the filaments formed septa, and division was complete within approximately 2 to 3 h. The variable survival of Salmonella strains at low aw highlights the importance of strain choice when researchers produce modelling data to simulate worst-case scenarios or conduct risk assessments based on laboratory data. The continued increase in Salmonella biomass at low aw (without a concomitant increase in microbial count) would not have been detected by traditional microbiological enumeration tests if the tests had been performed immediately after low-aw storage. If Salmonella strains form filaments in food products that have low aw values (0.92 to 0.98), there are significant implications for public health and for designing methods for microbiological monitoring. PMID:10742199

  4. Evaluation of penicylinders used in disinfectant testing: bacterial attachment and surface texture.

    Science.gov (United States)

    Cole, E C; Rutala, W A; Carson, J L

    1987-01-01

    Two possible deficiencies in the AOAC use-dilution method for registration of chemical disinfectants by the Environmental Protection Agency are examined: (1) the physical disparities among brands of penicylinders and (2) the variability of bacterial numbers on penicylinders depending upon test strain and penicylinder surface texture. Textural differences of 2 brands of stainless steel penicylinders, one brand of porcelain, and one brand of glass were assessed by scanning electron microscopy. A considerable variation in smoothness of both inner and outer surfaces of stainless steel and porcelain penicylinders was observed. Glass penicylinders were very smooth. Numbers of bacteria attached to a penicylinder were assessed by vortexing the penicylinders 30 s at No. 4 after using the AOAC method of bacterial inoculation and drying 40 min at 37 degrees C. With this methodology, stainless steel carriers retained the 3 AOAC-recommended bacterial test strains differentially: ca 10(7) for Pseudomonas aeruginosa, 5 X 10(6) for Staphylococcus aureus, and 10(6) for Salmonella choleraesuis; glass retained 10(6)-10(7) organisms of all 3 test strains; porcelain retained about that amount of S. aureus but 10(5)-10(6) P. aeruginosa and 10(3)-10(4) S. choleraesuis. These data suggest that disinfectants are not similarly challenged with the AOAC-recommended test bacteria and that an alternative method should be considered to ensure comparable numbers of bacteria on penicylinders.

  5. [A quantitative risk assessment model of salmonella on carcass in poultry slaughterhouse].

    Science.gov (United States)

    Zhang, Yu; Chen, Yuzhen; Hu, Chunguang; Zhang, Huaning; Bi, Zhenwang; Bi, Zhenqiang

    2015-05-01

    To construct a quantitative risk assessment model of salmonella on carcass in poultry slaughterhouse and to find out effective interventions to reduce salmonella contamination. We constructed a modular process risk model (MPRM) from evisceration to chilling in Excel Sheet using the data of the process parameters in poultry and the Salmomella concentration surveillance of Jinan in 2012. The MPRM was simulated by @ risk software. The concentration of salmonella on carcass after chilling was 1.96MPN/g which was calculated by model. The sensitive analysis indicated that the correlation coefficient of the concentration of salmonella after defeathering and in chilling pool were 0.84 and 0.34,which were the primary factors to the concentration of salmonella on carcass after chilling. The study provided a quantitative assessment model structure for salmonella on carcass in poultry slaughterhouse. The risk manager could control the contamination of salmonella on carcass after chilling by reducing the concentration of salmonella after defeathering and in chilling pool.

  6. Repetitive Hyperbaric Oxygenation Attenuates Reactive Astrogliosis and Suppresses Expression of Inflammatory Mediators in the Rat Model of Brain Injury

    Directory of Open Access Journals (Sweden)

    Irena Lavrnja

    2015-01-01

    Full Text Available The exact mechanisms by which treatment with hyperbaric oxygen (HBOT exerts its beneficial effects on recovery after brain injury are still unrevealed. Therefore, in this study we investigated the influence of repetitive HBOT on the reactive astrogliosis and expression of mediators of inflammation after cortical stab injury (CSI. CSI was performed on male Wistar rats, divided into control, sham, and lesioned groups with appropriate HBO. The HBOT protocol was as follows: 10 minutes of slow compression, 2.5 atmospheres absolute (ATA for 60 minutes, and 10 minutes of slow decompression, once a day for 10 consecutive days. Data obtained using real-time polymerase chain reaction, Western blot, and immunohistochemical and immunofluorescence analyses revealed that repetitive HBOT applied after the CSI attenuates reactive astrogliosis and glial scarring, and reduces expression of GFAP (glial fibrillary acidic protein, vimentin, and ICAM-1 (intercellular adhesion molecule-1 both at gene and tissue levels. In addition, HBOT prevents expression of CD40 and its ligand CD40L on microglia, neutrophils, cortical neurons, and reactive astrocytes. Accordingly, repetitive HBOT, by prevention of glial scarring and limiting of expression of inflammatory mediators, supports formation of more permissive environment for repair and regeneration.

  7. Real-time PCR Detection of Food-borne Pathogenic Salmonella spp

    DEFF Research Database (Denmark)

    Malorny, B.; Mäde, D.; Löfström, Charlotta

    2013-01-01

    Infections by Salmonella enterica are a significant public health concern worldwide. Salmonellae form a complex group of bacteria consisting of two species, six subspecies and more than 2500 serovars (serotypes). Mainly through ingestion of contaminated food or feed, they cause self-limiting gast......Infections by Salmonella enterica are a significant public health concern worldwide. Salmonellae form a complex group of bacteria consisting of two species, six subspecies and more than 2500 serovars (serotypes). Mainly through ingestion of contaminated food or feed, they cause self...

  8. Igg Subclasses Targeting the Flagella of Salmonella enterica Serovar Typhimurium Can Mediate Phagocytosis and Bacterial Killing

    Science.gov (United States)

    Goh, Yun Shan; Armour, Kathryn L; Clark, Michael R; Grant, Andrew J; Mastroeni, Pietro

    2016-01-01

    Invasive non-typhoidal Salmonella are a common cause of invasive disease in immuno-compromised individuals and in children. Multi-drug resistance poses challenges to disease control, with a critical need for effective vaccines. Flagellin is an attractive vaccine candidate due to surface exposure and high epitope copy number, but its potential as a target for opsonophacytic antibodies is unclear. We examined the effect of targeting flagella with different classes of IgG on the interaction between Salmonella Typhimurium and a human phagocyte-like cell line, THP-1. We tagged the FliC flagellar protein with a foreign CD52 mimotope (TSSPSAD) and bacteria were opsonized with a panel of humanised CD52 antibodies with the same antigen-binding V-region, but different constant regions. We found that IgG binding to flagella increases bacterial phagocytosis and reduces viable intracellular bacterial numbers. Opsonisation with IgG3, followed by IgG1, IgG4, and IgG2, resulted in the highest level of bacterial uptake and in the highest reduction in the intracellular load of viable bacteria. Taken together, our data provide proof-of-principle evidence that targeting flagella with antibodies can increase the antibacterial function of host cells, with IgG3 being the most potent subclass. These data will assist the rational design of urgently needed, optimised vaccines against iNTS disease. PMID:27366588

  9. Salmonella and Eggs: From Production to Plate

    Science.gov (United States)

    Whiley, Harriet; Ross, Kirstin

    2015-01-01

    Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption. PMID:25730295

  10. Salmonella and Eggs: From Production to Plate

    Directory of Open Access Journals (Sweden)

    Harriet Whiley

    2015-02-01

    Full Text Available Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption.

  11. Salmonella and eggs: from production to plate.

    Science.gov (United States)

    Whiley, Harriet; Ross, Kirstin

    2015-02-26

    Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption.

  12. Survival potential of wild type cellulose deficient Salmonella from the feed industry

    Directory of Open Access Journals (Sweden)

    Ballance Simon

    2009-11-01

    Full Text Available Abstract Background Biofilm has been shown to be one way for Salmonella to persist in the feed factory environment. Matrix components, such as fimbriae and cellulose, have been suggested to play an important role in the survival of Salmonella in the environment. Multicellular behaviour by Salmonella is often categorized according to colony morphology into rdar (red, dry and rough expressing curli fimbriae and cellulose, bdar (brown, dry and rough expressing curli fimbriae and pdar (pink, dry and rough expressing cellulose. The aim of the study was to look into the distribution of morphotypes among feed and fish meal factory strains of Salmonella, with emphasis on potential differences between morphotypes with regards to survival in the feed factory environment. Results When screening a total of 148 Salmonella ser. Agona, Salmonella ser. Montevideo, Salmonella ser. Senftenberg and Salmonella ser. Typhimurium strains of feed factory, human clinical and reference collection origin, as many as 99% were able to express rough morphology (rdar or bdar. The dominant morphotype was rdar (74%, however as many as 55% of Salmonella ser. Agona and 19% of Salmonella ser. Senftenberg displayed the bdar morphology. Inconsistency in Calcofluor binding, indicating expression of cellulose, was found among 25% of all the strains tested, however Salmonella ser. Agona showed to be highly consistent in Calcofluor binding (98%. In biofilm, Salmonella ser. Agona strains with bdar mophology was found to be equally tolerant to disinfection treatment as strains with rdar morphotype. However, rdar morphology appeared to be favourable in long term survival in biofilm in a very dry environment. Chemical analysis showed no major differences in polysaccharide content between bdar and rdar strains. Our results indicate that cellulose is not a major component of the Salmonella biofilm matrix. Conclusion The bdar morphotype is common among Salmonella ser. Agona strains isolated

  13. A Perspective on Invasive Salmonella Disease in Africa.

    Science.gov (United States)

    Crump, John A; Heyderman, Robert S

    2015-11-01

    Salmonella enterica is a leading cause of community-acquired bloodstream infection in Africa. The contribution of typhoidal and nontyphoidal Salmonella serovars to invasive disease varies considerably in place and time, even within the same country. Nonetheless, many African countries are now thought to experience typhoid fever incidence >100 per 100,000 per year with approximately 1% of patients dying. Invasive nontyphoidal Salmonella (iNTS) disease was estimated to cause 3.4 million illnesses and 681 316 deaths in 2010, with the most disease in Africa. Antimicrobial drug resistance is a growing problem in S. enterica that threatens to further compromise patient outcomes. Reservoirs for nontyphoidal Salmonella and the predominant routes of transmission for typhoidal and nontyphoidal Salmonella are not well understood in Africa, hampering the design of evidence-based, non-vaccine- and vaccine-based prevention measures. It is difficult to distinguish clinically invasive Salmonella disease from febrile illnesses caused by other pathogens. Blood cultures are the mainstay of laboratory diagnosis, but lack sensitivity due to the low magnitude of bacteremia, do not produce results at point of care, and are not widely available in Africa. Serologic approaches to diagnosis remain inaccurate, and nucleic acid amplification tests are also compromised by low concentrations of bacteria. High-throughput whole-genome sequencing, together with a range of novel analytic pipelines, has provided new insights into the complex pattern of epidemiology, pathogenesis, and host adaptation. Concerted efforts are therefore needed to apply these new tools in the context of high-quality field surveillance to improve diagnosis, patient management, control, and prevention of invasive Salmonella infections in Africa. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  14. Molecular Confirmation of Salmonella typhimuriumin Poultry from Kathmandu Valley

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar Adhikari

    2018-05-01

    Full Text Available A prevalence study was carried to isolate Salmonella typhimurium from blood (n= 50 and gut samples (n=100 of poultry in Kathmandu valley during early 2016. Salmonella typhimurium bacteria isolated in the selective media were biochemically confirmed based on Bergey’s Manual. Two sets of oligonucleotide primers-the genus specific 16S rRNA and the organism specific invA were employed for molecular level confirmation by the Polymerase Chain Reaction (PCR assay. The amplified fragments in 1% agarose gel observed at 406bp and 285bp, respectively confirmed the isolates to be Salmonella typhimurium. Of 150 samples tested, Salmonella typhimurium were isolated from 49 samples, among which nine were from blood (18% and forty from the gut (40%. The present result indicated an alarmingly high level of Salmonella typhimurium, which can result inzoonotic infection in humans owing to increased contact with poultry and consumption of poultry products in the Kathmandu valley.

  15. A Salmonella nanoparticle mimic overcomes multidrug resistance in tumours.

    Science.gov (United States)

    Mercado-Lubo, Regino; Zhang, Yuanwei; Zhao, Liang; Rossi, Kyle; Wu, Xiang; Zou, Yekui; Castillo, Antonio; Leonard, Jack; Bortell, Rita; Greiner, Dale L; Shultz, Leonard D; Han, Gang; McCormick, Beth A

    2016-07-25

    Salmonella enterica serotype Typhimurium is a food-borne pathogen that also selectively grows in tumours and functionally decreases P-glycoprotein (P-gp), a multidrug resistance transporter. Here we report that the Salmonella type III secretion effector, SipA, is responsible for P-gp modulation through a pathway involving caspase-3. Mimicking the ability of Salmonella to reverse multidrug resistance, we constructed a gold nanoparticle system packaged with a SipA corona, and found this bacterial mimic not only accumulates in tumours but also reduces P-gp at a SipA dose significantly lower than free SipA. Moreover, the Salmonella nanoparticle mimic suppresses tumour growth with a concomitant reduction in P-gp when used with an existing chemotherapeutic drug (that is, doxorubicin). On the basis of our finding that the SipA Salmonella effector is fundamental for functionally decreasing P-gp, we engineered a nanoparticle mimic that both overcomes multidrug resistance in cancer cells and increases tumour sensitivity to conventional chemotherapeutics.

  16. Serotype determination of Salmonella by xTAG assay.

    Science.gov (United States)

    Zheng, Zhibei; Zheng, Wei; Wang, Haoqiu; Pan, Jincao; Pu, Xiaoying

    2017-10-01

    Currently, no protocols or commercial kits are available to determine the serotypes of Salmonella by using Luminex MAGPIX®. In this study, an xTAG assay for serotype determination of Salmonella suitable for Luminex MAGPIX® is described and 228 Salmonella isolates were serotype determined by this xTAG assay. The xTAG assay consists of two steps: 1) Multiplex PCR to amplify simultaneously O, H and Vi antigen genes of Salmonella, and 2) Magplex-TAG™ microsphere hybridization to identify accurately the specific PCR products of different antigens. Compared with the serotyping results of traditional serum agglutination test, the sensitivity and specificity of the xTAG assay were 95.1% and 100%, respectively. The agreement rate of these two assays was 95.2%. Compared with Luminex xMAP® Salmonella Serotyping Assay (SSA) kit, the advantages of this xTAG assay are: First, the magnetic beads make it applicable to both the Luminex®100/200™ and MAGPIX® systems. Second, only primers rather than both primers and probes are needed in the xTAG assay, and the process of coupling antigen-specific oligonucleotide probes to beads is circumvented, which make the xTAG assay convenient to be utilized by other laboratories. The xTAG assay may serve as a rapid alternative or complementary method for traditional Salmonella serotyping tests, especially for laboratories that utilize the MAGPIX® systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Rapid detection and characterization of Salmonella enterica ...

    African Journals Online (AJOL)

    Multiplex polymerase chain reaction (PCR) was used for molecular typing of Salmonella enterica serovars in Egypt. During the summer of 2010, a total of 1075 samples were collected from cattle, sheep and poultry farms to be subjected for isolation of Salmonella (290 rectal swabs from cattle, 335 rectal swabs from sheep ...

  18. [Rapid methods for the genus Salmonella bacteria detection in food and raw materials].

    Science.gov (United States)

    Sokolov, D M; Sokolov, M S

    2013-01-01

    The article considers sanitary and epidemiological aspects and the impact of Salmonella food poisoning in Russia and abroad. The main characteristics of the agent (Salmonella enterica subsp. Enteritidis) are summarized. The main sources of human Salmonella infection are products of poultry and livestock (poultry, eggs, dairy products, meat products, etc.). Standard methods of identifying the causative agent, rapid (alternative) methods of analysis of Salmonella using differential diagnostic medium (MSRV, Salmosyst, XLT4-agar, agar-Rambach et al.), rapid tests Singlepath-Salmonella and PCR (food proof Salmonella) in real time were stated. Rapid tests provide is a substantial (at 24-48 h) reducing the time to identify Salmonella.

  19. Ludwig′s angina by Salmonella Typhi: A clinical dilemma

    Directory of Open Access Journals (Sweden)

    R K Mahajan

    2015-01-01

    Full Text Available Salmonella Typhi has rarely been associated with focal abscesses; and in literature, there is no evidence of its association with abscesses in the neck spaces. Ability of Salmonella Typhi to invade and localise in the neck spaces not only poses a diagnostic challenge but also underscores the necessity to understand the mechanisms that facilitate Salmonella Typhi to establish infections at sites completely non-traditional to the organism.

  20. Envelope exchange for the generation of live-attenuated arenavirus vaccines.

    Directory of Open Access Journals (Sweden)

    Andreas Bergthaler

    2006-06-01

    Full Text Available Arenaviruses such as Lassa fever virus cause significant mortality in endemic areas and represent potential bioterrorist weapons. The occurrence of arenaviral hemorrhagic fevers is largely confined to Third World countries with a limited medical infrastructure, and therefore live-attenuated vaccines have long been sought as a method of choice for prevention. Yet their rational design and engineering have been thwarted by technical limitations. In addition, viral genes had not been identified that are needed to cause disease but can be deleted or substituted to generate live-attenuated vaccine strains. Lymphocytic choriomeningitis virus, the prototype arenavirus, induces cell-mediated immunity against Lassa fever virus, but its safety for humans is unclear and untested. Using this virus model, we have developed the necessary methodology to efficiently modify arenavirus genomes and have exploited these techniques to identify an arenaviral Achilles' heel suitable for targeting in vaccine design. Reverse genetic exchange of the viral glycoprotein for foreign glycoproteins created attenuated vaccine strains that remained viable although unable to cause disease in infected mice. This phenotype remained stable even after extensive propagation in immunodeficient hosts. Nevertheless, the engineered viruses induced T cell-mediated immunity protecting against overwhelming systemic infection and severe liver disease upon wild-type virus challenge. Protection was established within 3 to 7 d after immunization and lasted for approximately 300 d. The identification of an arenaviral Achilles' heel demonstrates that the reverse genetic engineering of live-attenuated arenavirus vaccines is feasible. Moreover, our findings offer lymphocytic choriomeningitis virus or other arenaviruses expressing foreign glycoproteins as promising live-attenuated arenavirus vaccine candidates.

  1. Envelope Exchange for the Generation of Live-Attenuated Arenavirus Vaccines.

    Directory of Open Access Journals (Sweden)

    2006-06-01

    Full Text Available Arenaviruses such as Lassa fever virus cause significant mortality in endemic areas and represent potential bioterrorist weapons. The occurrence of arenaviral hemorrhagic fevers is largely confined to Third World countries with a limited medical infrastructure, and therefore live-attenuated vaccines have long been sought as a method of choice for prevention. Yet their rational design and engineering have been thwarted by technical limitations. In addition, viral genes had not been identified that are needed to cause disease but can be deleted or substituted to generate live-attenuated vaccine strains. Lymphocytic choriomeningitis virus, the prototype arenavirus, induces cell-mediated immunity against Lassa fever virus, but its safety for humans is unclear and untested. Using this virus model, we have developed the necessary methodology to efficiently modify arenavirus genomes and have exploited these techniques to identify an arenaviral Achilles' heel suitable for targeting in vaccine design. Reverse genetic exchange of the viral glycoprotein for foreign glycoproteins created attenuated vaccine strains that remained viable although unable to cause disease in infected mice. This phenotype remained stable even after extensive propagation in immunodeficient hosts. Nevertheless, the engineered viruses induced T cell-mediated immunity protecting against overwhelming systemic infection and severe liver disease upon wild-type virus challenge. Protection was established within 3 to 7 d after immunization and lasted for approximately 300 d. The identification of an arenaviral Achilles' heel demonstrates that the reverse genetic engineering of live-attenuated arenavirus vaccines is feasible. Moreover, our findings offer lymphocytic choriomeningitis virus or other arenaviruses expressing foreign glycoproteins as promising live-attenuated arenavirus vaccine candidates.

  2. Phenotypic and genotypic antimicrobial resistance and virulence genes of Salmonella enterica isolated from pet dogs and cats

    Science.gov (United States)

    Srisanga, Songsak; Angkititrakul, Sunpetch; Sringam, Patcharee; Le Ho, Phuong T.; Vo, An T. T.

    2017-01-01

    Salmonella enterica isolates (n = 122), including 32 serotypes from 113 dogs and 9 cats, were obtained from household dogs (n = 250) and cats (n = 50) during 2012–2015. The isolates were characterized by serotyping, antimicrobial resistance phenotyping and genotyping, and virulence gene screening. Serovars Weltevreden (15.6%) and Typhimurium (13.9%) were the most common. The majority (43%) of the isolates were multidrug resistant. The dog isolates (12.3%) harbored class 1 integrons, of which the dfrA12-aadA2 cassette was most frequent (66.7%). The only class integron in serovar Albany was located on a conjugative plasmid. Two ESBL-producing isolates (i.e., a serovar Krefeld and a serovar Enteritridis) carried blaTEM and blaCTX-M, and the blaTEM gene in both was horizontally transferred. Of the plasmid-mediated quinolone resistance genes tested, only qnrS (4.9%) was detected. Most Salmonella isolates harbored invA (100%), prgH (91.8%), and sipB (91%). Positive associations between resistance and virulence genes were observed for blaPSE-1/orgA, cmlA/spaN, tolC, and sul1/tolC (p resistance and virulence genes and that antimicrobial use in companion animals may select for the examined Salmonella virulence factors. PMID:27586467

  3. Salmonella rarely detected in Mississippi coastal waters and sediment.

    Science.gov (United States)

    Carr, M R; Wang, S Y; McLean, T I; Flood, C J; Ellender, R D

    2010-12-01

    Standards for the rapid detection of individual pathogens from environmental samples have not been developed, but in their absence, the use of molecular-based detection methods coupled with traditional microbiology techniques allows for rapid and accurate pathogen detection from environmental waters and sediment. The aim of this research was to combine the use of enrichment with PCR for detection of Salmonella in Mississippi coastal waters and sediment and observe if that presence correlated with levels of enterococci and climatological variables. Salmonella were primarily found in samples that underwent nutrient enrichment and were present more frequently in freshwater than marine waters. Salmonella were detected infrequently in marine and freshwater sediments. There was a significant positive correlation between the presence of detectable Salmonella and the average enterococcal count. An inverse relationship, however, was observed between the frequency of detection and the levels of salinity, turbidity and sunlight exposure. Results from this study indicated the presence of Salmonella in Mississippi coastal waters, and sediments are very low with significant differences between freshwater and marine environments. Using pathogenic and novel nonpathogenic molecular markers, Salmonella do not appear to be a significant pathogenic genus along the Mississippi Coast. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

  4. Survival and transmission of Salmonella enterica serovar typhimurium in an outdoor organic pig farming environment

    DEFF Research Database (Denmark)

    Jensen, Annette Nygaard; Dalsgaard, Anders; Stockmarr, Anders

    2006-01-01

    It was investigated how organic rearing conditions influence the Salmonella enterica infection dynamics in pigs and whether Salmonella persists in the paddock environment. Pigs inoculated with S. enterica serovar Typhimurium were grouped with Salmonella-negative tracer pigs. Bacteriological...... the seroprevalence. Salmonella persisted in the paddock environment, as Salmonella was isolated from 46% of soil and water samples (n = 294). After removal of pigs, Salmonella was found in soil samples for up to. 5 weeks and in shelter huts during the entire test period (7 weeks). Subsequent introduction...... of Salmonella-negative pigs into four naturally Salmonella-contaminated paddocks caused Salmonella infections of pigs in two paddocks. In one of these paddocks, all tracer pigs (n = 10) became infected, coinciding with a previous high Salmonella infection rate and high Salmonella excretion level. Our results...

  5. Immunomagnetic nanoparticle based quantitative PCR for rapid detection of Salmonella

    International Nuclear Information System (INIS)

    Bakthavathsalam, Padmavathy; Rajendran, Vinoth Kumar; Saran, Uttara; Chatterjee, Suvro; Ali, Baquir Mohammed Jaffar

    2013-01-01

    We have developed a rapid and sensitive method for immunomagnetic separation (IMS) of Salmonella along with their real time detection via PCR. Silica-coated magnetic nanoparticles were functionalized with carboxy groups to which anti-Salmonella antibody raised against heat-inactivated whole cells of Salmonella were covalently attached. The immuno-captured target cells were detected in beverages like milk and lemon juice by multiplex PCR and real time PCR with a detection limit of 10 4 cfu.mL −1 and 10 3 cfu.mL −1 , respectively. We demonstrate that IMS can be used for selective concentration of target bacteria from beverages for subsequent use in PCR detection. PCR also enables differentiation of Salmonella typhi and Salmonella paratyphi A using a set of four specific primers. In addition, IMS—PCR can be used as a screening tool in the food and beverage industry for the detection of Salmonella within 3–4 h which compares favorably to the time of several days that is needed in case of conventional detection based on culture and biochemical methods. (author)

  6. The tenth CRL-Salmonella workshop; 28 and 29 April 2005, Bilthoven, the Netherlands

    NARCIS (Netherlands)

    Mooijman KA; MGB

    2006-01-01

    De tiende workshop georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella) werd gehouden op 28 en 29 April 2005 in Bilthoven, Nederland. Deelnemers betroffen vertegenwoordigers van de Nationale Referentie Laboratoria voor Salmonella (NRLs-Salmonella) van de

  7. Report on the seventh workshop organised by CRL-Salmonella. Ploufragan (France), 28 May 2002

    NARCIS (Netherlands)

    Korver H; Raamsdonk EC van; Henken AM; MGB

    2002-01-01

    At 28 May 2002 a workshop was organised by the Community Reference Laboratory for Salmonella (CRL-Salmonella) in Ploufragan, France. All National Reference Laboratories for Salmonella (NRLs-Salmonella) of the EU Member States, with the exception of the Greek and the Northern-Ireland NRLs-Salmonella,

  8. Radiation-induced mutagenicity and lethality in Ames tester strains of Salmonella

    International Nuclear Information System (INIS)

    Isildar, M.; Bakale, G.

    1984-01-01

    Mutation and killing induced by X radiation and 60 Co γ radiation were studied in six different histidine-requiring auxotrophs of Salmonella typhimurium. Strain TA100, which is sensitive to base-pair substitutions, and strains TA2637 and TA98, which are sensitive to frameshifts, carry the pKM101 plasmid and exhibit significantly higher radiation-induced mutations compared to their plasmidless parent strains TA1535, TA1537, and TA1538, respectively. Among the plasmid-containing strains, TA98 and TA2637 are much more sensitive to the mutagenic action of radiation than is TA100 based on a comparison with their respective spontaneous mutation rates; however, no uniformity was observed in the responses of the strains to the lethal action of ionizing radiation. The following conclusions are consistent with these observations: (1) the standard Ames Salmonella assay correctly identifies ionizing radiation as a mutagenic agent; (2) frameshift-sensitive parent strains are more sensitive to the mutagenic effects of ionizing radiation than is the only strain studied that is sensitive to base-pair substitutions; and (3) enhancement of mutagenesis and survival is related to plasmid-mediated repair of DNA damage induced by ionizing radiation and does not involve damage induced by Cerenkov-generated uv radiation which is negligible for our irradiation conditions

  9. Relationship between aerobic bacteria, salmonellae and Campylobacter on broiler carcasses.

    Science.gov (United States)

    Cason, J A; Bailey, J S; Stern, N J; Whittemore, A D; Cox, N A

    1997-07-01

    Broiler carcasses were removed from commercial processing lines immediately after defeathering, before chilling, and after chilling to determine whether any relationship exists between aerobic bacteria and the human enteropathogens salmonellae and Campylobacter. In two experiments, a whole carcass rinse procedure was used to sample 30 carcasses after defeathering, 90 carcasses before chilling, and 90 carcasses after chilling, for a total of 210 different carcasses. Aerobic bacteria and Campylobacter spp. were enumerated and the incidence of salmonellae was determined. Salmonellae and Campylobacter incidences were 20 and 94%, respectively, for all carcasses sampled. After picking, neither salmonellae-positive nor Campylobacter-positive carcasses had mean aerobic most probable number (MPN) values that were different from carcasses negative for those organisms. Immediately before chilling, aerobic and Campylobacter counts were 7.12 and 5.33 log10 cfu per carcass, respectively. Immersion chilling reduced aerobic counts by approximately 1.8 log and Campylobacter by 1.5 log, with no change in salmonellae-positive carcasses. There was no difference in aerobic or Campylobacter counts between carcasses that were positive or negative for salmonellae at any of the sampling locations, nor was any correlation found between levels of aerobic organisms and Campylobacter. Carcasses with aerobic counts above the mean or more than one standard deviation above the mean also failed to show any correlation. Discriminant analysis indicated error rates as high as 50% when numbers of aerobic bacteria were used to predict incidence of salmonellae or Campylobacter on individual carcasses. Aerobic bacteria are not suitable as index organisms for salmonellae or Campylobacter on broiler carcasses.

  10. Epidemiological data on food poisonings in Japan focused on Salmonella, 1998-2004.

    Science.gov (United States)

    Toyofuku, H

    2008-09-01

    In Japan, the numbers and cases of food poisonings must be reported as required by the Food Sanitation Law. This paper focuses on Salmonella, one of the leading food-borne pathogens in Japan, and it analyses the reported food poisoning data to assess the nature of Salmonella-associated food-borne disease. Obviously, these data do not exactly reflect the burden of food-borne illness associated with Salmonella; however, trends in Salmonella food poisoning and implicated foods could be identified for the purpose of setting priorities to mitigate the risk of food-borne salmonellosis. Summary information of Salmonella food poisoning investigation reports submitted by health departments of all prefectures and major cities between January 1998 and December 2004 was analysed. Both the number of reports and the cases of Salmonella food poisoning decreased drastically from 1999 (831 Salmonella food poisoning reports with 11,877 cases) to 2001 (265 reports with 7011 cases), increased in 2002, and then decreased again in 2003 and 2004 (231 reports with 3793 cases in 2004). About 80% of the Salmonella food poisoning reports and cases were associated with Salmonella enteritidis throughout the study period. Food vehicles were identified in 17-25% of the Salmonella food poisoning reports. Between 1998 and 2002, 45-60% of the Salmonella food poisoning cases were associated with eggs; however, the percentage dropped to 24.2% in 2003. The number of Salmonella food poisoning reports associated with beef, pork and poultry meat, and raw vegetables, which have been frequently reported in other countries, were very limited. Among the identified locations of disease break outs, 30-49% occurred in restaurant settings and the percentage of cases in restaurants increased during the study period. Thirteen to 41% of the Salmonella food poisoning cases occurred within the home, and the percentage declined. Phage types 1 and 4 were the predominant S. enteritidis isolated in 1998 and 1999; however

  11. Specificity tests of an oligonucleotide probe against food-outbreak salmonella for biosensor detection

    Science.gov (United States)

    Chen, I.-H.; Horikawa, S.; Xi, J.; Wikle, H. C.; Barbaree, J. M.; Chin, B. A.

    2017-05-01

    Phage based magneto-elastic (ME) biosensors have been shown to be able to rapidly detect Salmonella in various food systems to serve food pathogen monitoring purposes. In this ME biosensor platform, the free-standing strip-shaped magneto-elastic sensor is the transducer and the phage probe that recognizes Salmonella in food serves as the bio-recognition element. According to Sorokulova et al. at 2005, a developed oligonucleotide probe E2 was reported to have high specificity to Salmonella enterica Typhimurium. In the report, the specificity tests were focused in most of Enterobacterace groups outside of Salmonella family. Here, to understand the specificity of phage E2 to different Salmonella enterica serotypes within Salmonella Family, we further tested the specificity of the phage probe to thirty-two Salmonella serotypes that were present in the major foodborne outbreaks during the past ten years (according to Centers for Disease Control and Prevention). The tests were conducted through an Enzyme linked Immunosorbent Assay (ELISA) format. This assay can mimic probe immobilized conditions on the magnetoelastic biosensor platform and also enable to study the binding specificity of oligonucleotide probes toward different Salmonella while avoiding phage/ sensor lot variations. Test results confirmed that this oligonucleotide probe E2 was high specific to Salmonella Typhimurium cells but showed cross reactivity to Salmonella Tennessee and four other serotypes among the thirty-two tested Salmonella serotypes.

  12. Heme oxygenase attenuates angiotensin II-mediated superoxide production in cultured mouse thick ascending loop of Henle cells.

    Science.gov (United States)

    Kelsen, Silvia; Patel, Bijal J; Parker, Lawson B; Vera, Trinity; Rimoldi, John M; Gadepalli, Rama S V; Drummond, Heather A; Stec, David E

    2008-10-01

    Heme oxygenase (HO)-1 induction can attenuate the development of angiotensin II (ANG II)-dependent hypertension. However, the mechanism by which HO-1 lowers blood pressure is not clear. The goal of this study was to test the hypothesis that induction of HO-1 can reduce the ANG II-mediated increase in superoxide production in cultured thick ascending loop of Henle (TALH) cells. Studies were performed on an immortalized cell line of mouse TALH (mTALH) cells. HO-1 was induced in cultured mTALH cells by treatment with cobalt protoporphyrin (CoPP, 10 microM) or hemin (50 microM) or by transfection with a plasmid containing the human HO-1 isoform. Treatment of mTALH cells with 10(-9) M ANG II increased dihydroethidium (DHE) fluorescence (an index of superoxide levels) from 35.5+/-5 to 136+/-18 relative fluorescence units (RFU)/microm2. Induction of HO-1 via CoPP, hemin, or overexpression of the human HO-1 isoform significantly reduced ANG II-induced DHE fluorescence to 64+/-5, 64+/-8, and 41+/-4 RFU/microm2, respectively. To determine which metabolite of HO-1 is responsible for reducing ANG II-mediated increases in superoxide production in mTALH cells, cells were preincubated with bilirubin or carbon monoxide (CO)-releasing molecule (CORM)-A1 (each at 100 microM) before exposure to ANG II. DHE fluorescence averaged 80+/-7 RFU/microm2 after incubation with ANG II and was significantly decreased to 55+/-7 and 53+/-4 RFU/microm2 after pretreatment with bilirubin and CORM-A1. These results demonstrate that induction of HO-1 in mTALH cells reduces the levels of ANG II-mediated superoxide production through the production of both bilirubin and CO.

  13. Breast abscess in a man due to Salmonella enterica serotype Enteritidis.

    Science.gov (United States)

    Brncic, Nada; Gorup, Lari; Strcic, Miroslav; Abram, Maja; Mustac, Elvira

    2012-01-01

    Nontyphoidal salmonellae can cause breast infection only exceptionally. A case of breast abscess in a 70-year-old man due to Salmonella enterica serotype Enteritidis (Salmonella Enteritidis) is reported. The infection was successfully treated with a combination of surgical and antibiotic treatment.

  14. Prevalence and characterization of Salmonella among humans in Ghana

    DEFF Research Database (Denmark)

    Andoh, Linda Aurelia; Ahmed, Shabana; Olsen, John Elmerdahl

    2017-01-01

    Background Non-typhoidal Salmonella (NTS) is a public health problem worldwide and particularly in Africa with high disease burden. This study characterized Salmonella isolates from humans in Ghana to determine serovar distribution, phage types, and antimicrobial resistance. Further, the clonal...... relatedness among isolates was determined. Methods One hundred and thirty-seven Salmonella isolates (111 clinical and 26 public toilet) were characterized using standard serotyping, phage typing, and antimicrobial susceptibility testing methods. The molecular epidemiology of common serovars (Salmonella....... Fifty-eight (n = 58/112; 54.5%) strains were multi-resistant with low resistance to cephalosporins ceftazidime (8.0%), cefotaxime (4.5%), and cefoxitin (2.7%) with synergy to clavulanic acid indicating possible ESBLs. Isolates showed high resistance to trimethoprim (66.1%), tetracycline (61...

  15. Evaluation of different analysis and identification methods for Salmonella detection in surface drinking water sources

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Bing-Mu, E-mail: bmhsu@ccu.edu.tw [Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC (China); Huang, Kuan-Hao; Huang, Shih-Wei [Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC (China); Tseng, Kuo-Chih [Department of Internal Medicine, Buddhist Dalin Tzu Chi General Hospital, Chiayi, Taiwan, ROC (China); Su, Ming-Jen [Department of Clinical Pathology, Buddhist Dalin Tzu Chi General Hospital, Chiayi, Taiwan, ROC (China); Lin, Wei-Chen; Ji, Dar-Der [Research and Diagnostic Center, Centers for Disease Control, Taipei, Taiwan, ROC (China); Shih, Feng-Cheng; Chen, Jyh-Larng [Department of Environmental Engineering and Health, Yuanpei University of Science and Technology, HsinChu, Taiwan, ROC (China); Kao, Po-Min [Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC (China)

    2011-09-15

    The standard method for detecting Salmonella generally analyzes food or fecal samples. Salmonella often occur in relatively low concentrations in environmental waters. Therefore, some form of concentration and proliferation may be needed. This study compares three Salmonella analysis methods and develops a new Salmonella detection procedure for use in environmental water samples. The new procedure for Salmonella detection include water concentration, nutrient broth enrichment, selection of Salmonella containing broth by PCR, isolation of Salmonella strains by selective culture plates, detection of possible Salmonella isolate by PCR, and biochemical testing. Serological assay and pulsed-field gel electrophoresis (PFGE) can be used to identify Salmonella serotype and genotype, respectively. This study analyzed 116 raw water samples taken from 18 water plants and belonging to 5 watersheds. Of these 116, 10 water samples (8.6%) taken from 7 water plants and belonging to 4 watersheds were positive for a Salmonella-specific polymerase chain reaction targeting the invA gene. Guided by serological assay results, this study identified 7 cultured Salmonella isolates as Salmonella enterica serovar: Alnaby, Enteritidis, Houten, Montevideo, Newport, Paratyphi B var. Java, and Victoria. These seven Salmonella serovars were identified in clinical cases for the same geographical areas, but only one of them was 100% homologous with clinical cases in the PFGE pattern. - Research highlights: {yields} A new Salmonella detecting procedure for environmental water is developed. {yields} Salmonella isolates are identified by serological assay and PFGE. {yields} A total of seven Salmonella serovars is isolated from environmental water.

  16. Evaluation of different analysis and identification methods for Salmonella detection in surface drinking water sources

    International Nuclear Information System (INIS)

    Hsu, Bing-Mu; Huang, Kuan-Hao; Huang, Shih-Wei; Tseng, Kuo-Chih; Su, Ming-Jen; Lin, Wei-Chen; Ji, Dar-Der; Shih, Feng-Cheng; Chen, Jyh-Larng; Kao, Po-Min

    2011-01-01

    The standard method for detecting Salmonella generally analyzes food or fecal samples. Salmonella often occur in relatively low concentrations in environmental waters. Therefore, some form of concentration and proliferation may be needed. This study compares three Salmonella analysis methods and develops a new Salmonella detection procedure for use in environmental water samples. The new procedure for Salmonella detection include water concentration, nutrient broth enrichment, selection of Salmonella containing broth by PCR, isolation of Salmonella strains by selective culture plates, detection of possible Salmonella isolate by PCR, and biochemical testing. Serological assay and pulsed-field gel electrophoresis (PFGE) can be used to identify Salmonella serotype and genotype, respectively. This study analyzed 116 raw water samples taken from 18 water plants and belonging to 5 watersheds. Of these 116, 10 water samples (8.6%) taken from 7 water plants and belonging to 4 watersheds were positive for a Salmonella-specific polymerase chain reaction targeting the invA gene. Guided by serological assay results, this study identified 7 cultured Salmonella isolates as Salmonella enterica serovar: Alnaby, Enteritidis, Houten, Montevideo, Newport, Paratyphi B var. Java, and Victoria. These seven Salmonella serovars were identified in clinical cases for the same geographical areas, but only one of them was 100% homologous with clinical cases in the PFGE pattern. - Research highlights: → A new Salmonella detecting procedure for environmental water is developed. → Salmonella isolates are identified by serological assay and PFGE. → A total of seven Salmonella serovars is isolated from environmental water.

  17. Bacteriological detection of Salmonella in the presence of competitive micro-organisms (A collaborative study amongst the National Reference Laboratories for Salmonella)

    NARCIS (Netherlands)

    Voogt N; Veld PH in 't; Nagelkerke N; Henken AM; MGB

    1997-01-01

    A second bacteriological collaborative study in which the National Reference Laboratories (NRLs) for Salmonella participated was organized by the Community Reference Laboratory for Salmonella. The main objective of this study was to evaluate differences in results between the NRLs of detection of

  18. An oral Salmonella-based vaccine inhibits liver metastases by promoting tumor-specific T cell-mediated immunity in celiac & portal lymph nodes. A preclinical study.

    Directory of Open Access Journals (Sweden)

    Alejandrina eVendrell

    2016-03-01

    Full Text Available Primary tumor excision is one of the therapies of cancer most widely used. However, the risk of metastases development still exists following tumor resection. The liver is a common site of metastatic disease for numerous cancers. Breast cancer is one of the most frequent source of metastases to the liver. The aim of this work was to evaluate the efficacy of the orally-administered Salmonella Typhi vaccine strain CVD 915 on the development of liver metastases in a mouse model of breast cancer. To this end, one group of BALB/c mice was immunized with CVD 915 via o.g. while another received PBS as a control. After 24 h, mice were injected with LM3 mammary adenocarcinoma cells into the spleen and subjected to splenectomy. This oral Salmonella-based vaccine produced an antitumor effect, leading to a decrease in the number and volume of liver metastases. Immunization with Salmonella induced an early cellular immune response in mice. This innate stimulation rendered a large production of IFN-γ by intrahepatic immune cells (IHIC detected within 24 h. An antitumor adaptive immunity was found in the liver and celiac & portal lymph nodes (LDLN 21 days after oral bacterial inoculation. The antitumor immune response inside the liver was associated with increased CD4+ and DC cell populations as well as with an inflammatory infiltrate located around liver metastatic nodules. Enlarged levels of inflammatory cytokines (IFN-γ and TNF were also detected in IHIC. Furthermore, a tumor-specific production of IFN-γ and TNF as well as tumor-specific IFN-γ-producing CD8 T cells (CD8+IFN-γ+ were found in the celiac & portal lymph nodes of Salmonella-treated mice. This study provides first evidence for the involvement of LDLN in the development of an efficient cellular immune response against hepatic tumors, which resulted in the elimination of liver metastases after oral Salmonella-based vaccination.

  19. Prevalence of Salmonella on Sheep Carcasses Slaughtered at ...

    African Journals Online (AJOL)

    ... indicated that Salmonella is a common problem in slaughtered sheep carcasses in Adama municipal abattoir. Therefore, Sources of pathogens in food animals need to be investigated and a further study of pathogens in the food chain is recommended. Keywords: Adama Carcass Ethiopia Prevalence Salmonella Sheep.

  20. The consequences of a sudden demographic change on the seroprevalence pattern, virulence genes, identification and characterisation of integron-mediated antibiotic resistance in the Salmonella enterica isolated from clinically diarrhoeic humans in Egypt.

    Science.gov (United States)

    Osman, K M; Hassan, W M M; Mohamed, R A H

    2014-08-01

    The present study was undertaken to identify and characterise integrons and integrated resistance gene cassettes among eight multidrug-resistant (MDR) Salmonella serovars isolated from humans in Egypt. Virulotyping by polymerase chain reaction (PCR) was used for the detection of the presence of virulence genes. Integron PCR was used to detect the presence of class 1 in the MDR strains. The associated individual resistance gene cassettes were identified using specific PCRs. The isolated serovars were Salmonella Grampian (C1; 2/5), Larose (C1; 1/5), Hato (B; 1/5) and Texas (B; 1/5). Among the Salmonella serovars, five Salmonella isolates showed the highest resistance to amoxicillin, ampicillin, chloramphenicol, lincomycin, gentamicin, nalidixic acid, streptomycin and trimethoprim (100%), followed by neomycin, norfloxacin and tetracycline (80%), while the lowest resistance was recorded to colistin sulphate and ciprofloxacin in percentages of 20 and 40%, respectively. The invA, avrA, ssaQ, mgtC, siiD and sopB genes were detected in all isolates (100%), while the spvC and gipA genes were totally (100%) absent from all isolates. The remaining three virulence genes were diversely distributed as follows: the bcfC gene was detected in all isolates except Salmonella Hato (80%); the sodC1 gene was detected only in Salmonella Grampian and Salmonella Texas (60%); and the sopE1 gene was detected only in Salmonella Grampian, Hato and Texas (60%). Class 1 integrons were detected in 90% of the MDR isolates, comprising serovars Muenster, Florian, Noya, Grampian, Larose, Hato and Texas. Of the class 1 integron-positive isolates, 45% harboured Salmonella genomic island 1 (SGI1) either right junction or right and left junction having an A-C-S-T phenotype. Of the class 1 integron-positive isolates, 44% harboured integron gene cassette aadA2, while 11% harboured the floR gene present in multidrug resistance flanked by two integrons of SGI1. The results of the present study indicate that

  1. Inactivation of Salmonella and Listeria in ground chicken breast meat during thermal processing.

    Science.gov (United States)

    Murphy, R Y; Marks, B P; Johnson, E R; Johnson, M G

    1999-09-01

    Thermal inactivation of six Salmonella spp. and Listeria innocua was evaluated in ground chicken breast and liquid medium. Survival of Salmonella and Listeria was affected by the medium composition. Under the same thermal process condition, significantly more Salmonella and Listeria survived in chicken breast meat than in 0.1% peptone-agar solution. The thermal lethality of six tested Salmonella spp. was additive in chicken meat. Survival of Listeria in chicken meat during thermal processing was not affected by the presence of the six Salmonella spp. Sample size and shape affected the inactivation of Salmonella and Listeria in chicken meat during thermal processing.

  2. Comparative Sequence Analysis of Multidrug-Resistant IncA/C Plasmids from Salmonella enterica.

    Science.gov (United States)

    Hoffmann, Maria; Pettengill, James B; Gonzalez-Escalona, Narjol; Miller, John; Ayers, Sherry L; Zhao, Shaohua; Allard, Marc W; McDermott, Patrick F; Brown, Eric W; Monday, Steven R

    2017-01-01

    Determinants of multidrug resistance (MDR) are often encoded on mobile elements, such as plasmids, transposons, and integrons, which have the potential to transfer among foodborne pathogens, as well as to other virulent pathogens, increasing the threats these traits pose to human and veterinary health. Our understanding of MDR among Salmonella has been limited by the lack of closed plasmid genomes for comparisons across resistance phenotypes, due to difficulties in effectively separating the DNA of these high-molecular weight, low-copy-number plasmids from chromosomal DNA. To resolve this problem, we demonstrate an efficient protocol for isolating, sequencing and closing IncA/C plasmids from Salmonella sp. using single molecule real-time sequencing on a Pacific Biosciences (Pacbio) RS II Sequencer. We obtained six Salmonella enterica isolates from poultry, representing six different serovars, each exhibiting the MDR-Ampc resistance profile. Salmonella plasmids were obtained using a modified mini preparation and transformed with Escherichia coli DH10Br. A Qiagen Large-Construct kit™ was used to recover highly concentrated and purified plasmid DNA that was sequenced using PacBio technology. These six closed IncA/C plasmids ranged in size from 104 to 191 kb and shared a stable, conserved backbone containing 98 core genes, with only six differences among those core genes. The plasmids encoded a number of antimicrobial resistance genes, including those for quaternary ammonium compounds and mercury. We then compared our six IncA/C plasmid sequences: first with 14 IncA/C plasmids derived from S. enterica available at the National Center for Biotechnology Information (NCBI), and then with an additional 38 IncA/C plasmids derived from different taxa. These comparisons allowed us to build an evolutionary picture of how antimicrobial resistance may be mediated by this common plasmid backbone. Our project provides detailed genetic information about resistance genes in

  3. Comparative Sequence Analysis of Multidrug-Resistant IncA/C Plasmids from Salmonella enterica

    Directory of Open Access Journals (Sweden)

    Maria Hoffmann

    2017-08-01

    Full Text Available Determinants of multidrug resistance (MDR are often encoded on mobile elements, such as plasmids, transposons, and integrons, which have the potential to transfer among foodborne pathogens, as well as to other virulent pathogens, increasing the threats these traits pose to human and veterinary health. Our understanding of MDR among Salmonella has been limited by the lack of closed plasmid genomes for comparisons across resistance phenotypes, due to difficulties in effectively separating the DNA of these high-molecular weight, low-copy-number plasmids from chromosomal DNA. To resolve this problem, we demonstrate an efficient protocol for isolating, sequencing and closing IncA/C plasmids from Salmonella sp. using single molecule real-time sequencing on a Pacific Biosciences (Pacbio RS II Sequencer. We obtained six Salmonella enterica isolates from poultry, representing six different serovars, each exhibiting the MDR-Ampc resistance profile. Salmonella plasmids were obtained using a modified mini preparation and transformed with Escherichia coli DH10Br. A Qiagen Large-Construct kit™ was used to recover highly concentrated and purified plasmid DNA that was sequenced using PacBio technology. These six closed IncA/C plasmids ranged in size from 104 to 191 kb and shared a stable, conserved backbone containing 98 core genes, with only six differences among those core genes. The plasmids encoded a number of antimicrobial resistance genes, including those for quaternary ammonium compounds and mercury. We then compared our six IncA/C plasmid sequences: first with 14 IncA/C plasmids derived from S. enterica available at the National Center for Biotechnology Information (NCBI, and then with an additional 38 IncA/C plasmids derived from different taxa. These comparisons allowed us to build an evolutionary picture of how antimicrobial resistance may be mediated by this common plasmid backbone. Our project provides detailed genetic information about

  4. Salmonella epidemiology: A whirlwind of change.

    Science.gov (United States)

    Besser, John M

    2018-05-01

    The field of infectious disease epidemiology for Salmonella and other enteric pathogens is undergoing some of the most profound changes since the time of Kauffman and White. Rapid advances in "big data" technologies such as genomics and metagenomics are making it possible to monitor and control salmonellosis in new and exciting ways. Epidemiological methods are becoming increasingly robust through the routine use of standardized hypothesis-generating questionnaires, iterative open-ended interviewing, informational trace-backs and new modeling techniques for describing the attribution of disease to food sources. In addition, Salmonella epidemiology is facing important challenges and new opportunities due to the rapid adoption of culture independent diagnostic test panels by clinical laboratories. Where is this unprecedented wave of change taking us? This chapter will examine emerging trends in Salmonella epidemiology, and take a peek into the not-so-distant future. Published by Elsevier Ltd.

  5. Detection of Salmonella in Meat

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Hansen, Flemming; Mansdal, Susanne

    2012-01-01

    Cost-effective and rapid monitoring of Salmonella in the meat production chain can contribute to food safety. The objective of this study was to validate an easy-to-use pre-PCR sample preparation method based on a simple boiling protocol for screening of Salmonella in meat and carcass swab samples...... obtained (SP, SE, and AC were 100, 95, and 97%, respectively). This test is under implementation by the Danish meat industry, and can be useful for screening of large number of samples in the meat production, especially for fast release of minced meat with a short shelf life....

  6. Advanced Oxidation Process sanitization of hatching eggs reduces Salmonella in broiler chicks.

    Science.gov (United States)

    Rehkopf, A C; Byrd, J A; Coufal, C D; Duong, T

    2017-10-01

    The microbial quality of eggs entering the hatchery is an important critical control point for biosecurity, pathogen reduction, and food safety programs in poultry production. Developing interventions to reduce Salmonella contamination of eggs is important to improving the microbial food safety of poultry and poultry products. The hydrogen peroxide (H2O2) and ultraviolet light (UV) Advanced Oxidation Process (AOP) has been previously demonstrated to be effective in reducing Salmonella on the surface of experimentally contaminated eggs. The objective of this study was to evaluate the effect of treating eggs with an egg-sanitizing apparatus using the H2O2/UV AOP on Salmonella contamination during incubation, hatching, and in broiler chicks during grow-out. Experimentally contaminated eggs were treated using the automated H2O2/UV AOP egg sanitizer and incubated for 21 d. AOP sanitization reduced Salmonella up to 7 log10 cfu egg-1 (P Salmonella positive eggs by up to 75% (P Salmonella-positive eggs during incubation. Additionally, Salmonella was recovered from more chicks hatched from untreated eggs than from eggs treated using the H2O2/UV AOP egg sanitizer (P Salmonella contamination on the surface of eggs using the H2O2/UV AOP egg sanitizer prior to incubation may reduce the gastrointestinal colonization of chicks by Salmonella. © 2017 Poultry Science Association Inc.

  7. Commercially laid eggs vs. discarded hatching eggs: contamination by Salmonella spp.

    Science.gov (United States)

    Kottwitz, Luciana B M; Leão, Joice Aparecida; Back, Alberto; Rodrigues, Dalia dos P; Magnani, Marciane; de Oliveira, Tereza C R M

    2013-01-01

    Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.

  8. Prevalence of salmonella in captive reptiles from Croatia

    DEFF Research Database (Denmark)

    Lukac, Maja; Pedersen, Karl; Prukner-Radovcic, Estella

    2015-01-01

    from 200 apparently healthy reptiles were tested for Salmonella excretions by bacteriologic culture and serotyping. These 200 individual reptiles included 31 lizards, 79 chelonians, and 90 snakes belonging to private owners or housed at the Zagreb Zoo, Croatia. Salmonella was detected in a total of 13...

  9. Epidemiological investigation of Salmonella enterica serovar Kedougou in Thailand.

    Science.gov (United States)

    Pornruangwong, Srirat; Hendriksen, Rene S; Pulsrikarn, Chaiwat; Bangstrakulnonth, Aroon; Mikoleit, Matthew; Davies, Rob H; Aarestrup, Frank M; Garcia-Migura, Lourdes

    2011-02-01

    Salmonella enterica serovar Kedougou is among the top 10 serovars reported in northern Thailand. The objective of this study was to identify risk factors associated with Salmonella Kedougou infection in Thailand and to compare the molecular types and antimicrobial resistance with Salmonella Kedougou isolates of human origin from United States and of animal origin from the United Kingdom. Data from 13,976 Salmonella infections of which 253 were Salmonella Kedougou collected in Thailand between 2002 and 2008 were analyzed by logistic regression. Antimicrobial susceptibility testing and pulsed-field gel electrophoresis (PFGE) were performed on selected Salmonella Kedougou strains causing infections in Thailand (n = 66), and compared to isolates from the United States (n = 5) and the United Kingdom (n = 20). Logistic analysis revealed season (hot/dry; p = 0.023), region (northern Thailand; p Thailand were resistant to third-generation cephalosporins: two harbored bla(CTX-M-63) and one bla(CMY-2). PFGE revealed 45 unique clusters. Isolates obtained from humans in Thailand and the United States presented identical PFGE profiles suggesting a travel association, whereas the majority of the animal isolates from United Kingdom clustered separately. This study reveals Salmonella Kedougou as a major cause of human infections in northern Thailand especially during the hot period and suggests a global spread probably due to travel. The clonal types causing infections in humans differed from those observed in animals in United Kingdom, which suggests the absence of an epidemiological link and could suggest differences in virulence. The high frequency of antimicrobial resistance, including emergence of resistance to fluoroquinolones and third-generation cephalosporins, might pose problems for treatment of infections.

  10. Genotypic and phenotypic characterization of multidrug resistant Salmonella Typhimurium and Salmonella Kentucky strains recovered from chicken carcasses.

    Directory of Open Access Journals (Sweden)

    Rizwana Tasmin

    Full Text Available Salmonella Typhimurium is the leading cause of human non-typhoidal gastroenteritis in the US. S. Kentucky is one the most commonly recovered serovars from commercially processed poultry carcasses. This study compared the genotypic and phenotypic properties of two Salmonella enterica strains Typhimurium (ST221_31B and Kentucky (SK222_32B recovered from commercially processed chicken carcasses using whole genome sequencing, phenotype characterizations and an intracellular killing assay. Illumina MiSeq platform was used for sequencing of two Salmonella genomes. Phylogenetic analysis employing homologous alignment of a 1,185 non-duplicated protein-coding gene in the Salmonella core genome demonstrated fully resolved bifurcating patterns with varying levels of diversity that separated ST221_31B and SK222_32B genomes into distinct monophyletic serovar clades. Single nucleotide polymorphism (SNP analysis identified 2,432 (ST19 SNPs within 13 Typhimurium genomes including ST221_31B representing Sequence Type ST19 and 650 (ST152 SNPs were detected within 13 Kentucky genomes including SK222_32B representing Sequence Type ST152. In addition to serovar-specific conserved coding sequences, the genomes of ST221_31B and SK222_32B harbor several genomic regions with significant genetic differences. These included phage and phage-like elements, carbon utilization or transport operons, fimbriae operons, putative membrane associated protein-encoding genes, antibiotic resistance genes, siderophore operons, and numerous hypothetical protein-encoding genes. Phenotype microarray results demonstrated that ST221_31B is capable of utilizing certain carbon compounds more efficiently as compared to SK222_3B; namely, 1,2-propanediol, M-inositol, L-threonine, α-D-lactose, D-tagatose, adonitol, formic acid, acetoacetic acid, and L-tartaric acid. ST221_31B survived for 48 h in macrophages, while SK222_32B was mostly eliminated. Further, a 3-fold growth of ST221_31B was

  11. Immunity to intestinal pathogens: lessons learned from Salmonella

    Science.gov (United States)

    McSorley, Stephen J.

    2014-01-01

    Summary Salmonella are a common source of food or water-borne infection and cause a wide range of clinical disease in human and animal hosts. Salmonella are relatively easy to culture and manipulate in a laboratory setting, and the infection of laboratory animals induces robust innate and adaptive immune responses. Thus, immunologists have frequently turned to Salmonella infection models to expand understanding of immunity to intestinal pathogens. In this review, I summarize current knowledge of innate and adaptive immunity to Salmonella and highlight features of this response that have emerged from recent studies. These include the heterogeneity of the antigen-specific T-cell response to intestinal infection, the prominence of microbial mechanisms to impede T and B-cell responses, and the contribution of non-cognate pathways for elicitation of T-cell effector functions. Together, these different issues challenge an overly simplistic view of host-pathogen interaction during mucosal infection but also allow deeper insight into the real-world dynamic of protective immunity to intestinal pathogens. PMID:24942689

  12. Effects of propolis from Brazil and Bulgaria on Salmonella serovars

    Directory of Open Access Journals (Sweden)

    R. O. Orsi

    2007-01-01

    Full Text Available Propolis shows biological properties such as antibacterial action. This bee product has a complex chemical composition, which depends on the local flora where it is produced. Salmonella serovars are responsible for human diseases that range from localized gastroenteritis to systemic infections. The aim of the present study was to investigate the susceptibility of Salmonella strains, isolated from food and infectious processes, to the antibacterial action of Brazilian and Bulgarian propolis, as well as to determine the behavior of these bacteria, according to the incubation period, in medium plus propolis. Dilution of ethanolic extract of propolis in agar was the used method. Brazilian and Bulgarian propolis showed an antibacterial action against all Salmonella serovars. The minimal inhibitory concentrations (MIC of propolis were similar, although they were collected in different geographic regions. Salmonella typhimurium, isolated from human infection, was more resistant to propolis than Salmonella enteritidis.

  13. Isolation and identification of Salmonella spp. in environmental water by molecular technology in Taiwan

    Science.gov (United States)

    Kuo, Chun Wei; Hao Huang, Kuan; Hsu, Bing Mu; Tsai, Hsien Lung; Tseng, Shao Feng; Shen, Tsung Yu; Kao, Po Min; Shen, Shu Min; Chen, Jung Sheng

    2013-04-01

    Salmonella spp. is one of the most important causal agents of waterborne diseases. The taxonomy of Salmonella is very complicated and its genus comprises more than 2,500 serotypes. The detection of Salmonella in environmental water samples by routines culture methods using selective media and characterization of suspicious colonies based on biochemical tests and serological assay are generally time consuming. To overcome this drawback, it is desirable to use effective method which provides a higher discrimination and more rapid identification about Salmonella in environmental water. The aim of this study is to investigate the occurrence of Salmonella using molecular technology and to identify the serovars of Salmonella isolates from 70 environmental water samples in Taiwan. The analytical procedures include membrane filtration, non-selective pre-enrichment, selective enrichment of Salmonella. After that, we isolated Salmonella strains by selective culture plates. Both selective enrichment and culture plates were detected by Polymerase Chain Reaction (PCR). Finally, the serovars of Salmonella were confirmed by using biochemical tests and serological assay. In this study, 15 water samples (21.4%) were identified as Salmonella by PCR. The positive water samples will further identify their serotypes by culture method. The presence of Salmonella in environmental water indicates the possibility of waterborne transmission in drinking watershed. Consequently, the authorities need to provide sufficient source protection and to maintain the system for disease prevention. Keywords: Salmonella spp., serological assay, PCR

  14. Spirulina vesicolor Improves Insulin Sensitivity and Attenuates Hyperglycemia-Mediated Oxidative Stress in Fructose-Fed Rats

    Directory of Open Access Journals (Sweden)

    Walaa Hozayen

    2016-03-01

    Full Text Available Aim: The current study aimed to investigate the anti-hyperglycemic, anti-hyperlipidemic and insulin sensitizing effects of the cyanobacterium Spirulina vesicolor extract in fructose-fed rats. Materials and Methods: Rats were fed 30% fructose solution in drinking water for 4 weeks. Animals exhibited hyperglycemia and hyperinsulinemia were selected for further investigations. Diabetic and control rats were orally supplemented with 50 mg/kg body weight S. vesicolor extract for 4 weeks. Results: At the end of 8 weeks, fructose-fed rats showed significant increase in serum glucose, insulin, cholesterol, triglycerides, cardiovascular risk indices and insulin resistance. Treatment of the fructose-fed rats with S. vesicolor extract improved this metabolic profile. Fructose feeding produced a significant increase in serum tumor necrosis factor alpha (TNF-α and a decrease in adiponectin levels. In addition, fructose-fed rats exhibited a significant increase in liver, kidney and heart lipid peroxidation levels, and declined antioxidant defenses. Supplementation of the fructose-fed rats with S. vesicolor extract reversed these alterations. Conclusion: S. vesicolor attenuates hyperglycemia-mediated oxidative stress and inflammation, and is thus effective in improving insulin sensitivity in fructose-fed rats. [J Complement Med Res 2016; 5(1.000: 57-64

  15. Chinese Herbal Formula, Modified Danggui Buxue Tang, Attenuates Apoptosis of Hematopoietic Stem Cells in Immune-Mediated Aplastic Anemia Mouse Model

    Directory of Open Access Journals (Sweden)

    Jingwei Zhou

    2017-01-01

    Full Text Available A derivative formula, DGBX, which is composed of three herbs (Radix astragali, Radix Angelicae sinensis, and Coptis chinensis Franch, is derived from a famous Chinese herbal formula, Danggui Buxue Tang (DBT (Radix astragali and Radix Angelicae sinensis. We aimed to investigate the effects of DGBX on the regulation of the balance between proliferation and apoptosis of hematopoietic stem cells (HSCs due to the aberrant immune response in a mouse model of aplastic anemia (AA. Cyclosporine (CsA, an immunosuppressor, was used as the positive control. Our results indicated that DGBX could downregulate the production of IFNγ in bone marrow cells by interfering with the binding between SLAM and SAP and the expressions of Fyn and T-bet. This herbal formula can also inhibit the activation of Fas-mediated apoptosis, interferon regulatory factor-1-induced JAK/Stat, and eukaryotic initiation factor 2 signaling pathways and thereby induce proliferation and attenuate apoptosis of HSCs. In conclusion, DGBX can relieve the immune-mediated destruction of HSCs, repair hematopoietic failure, and recover the hematopoietic function of HSCs in hematogenesis. Therefore, DGBX can be used in traditional medicine against AA as a complementary and alternative immunosuppressive therapeutic formula.

  16. 75 FR 66769 - Draft Compliance Policy Guide Sec. 690.800 Salmonella

    Science.gov (United States)

    2010-10-29

    ...] Draft Compliance Policy Guide Sec. 690.800 Salmonella in Animal Feed; Availability; Extension of Comment... that are adulterated due to the presence of Salmonella. The Agency is taking this action in response to... action against animal feed or feed ingredients that are adulterated due to the presence of Salmonella...

  17. Epidemiological Investigation of Salmonella enterica Serovar Kedougou in Thailand

    DEFF Research Database (Denmark)

    Pornruangwong, Srirat; Hendriksen, Rene S.; Pulsrikarn, Chaiwat

    2011-01-01

    with Salmonella Kedougou isolates of human origin from United States and of animal origin from the United Kingdom. Methods: Data from 13,976 Salmonella infections of which 253 were Salmonella Kedougou collected in Thailand between 2002 and 2008 were analyzed by logistic regression. Antimicrobial susceptibility...... association, whereas the majority of the animal isolates from United Kingdom clustered separately. Conclusions: This study reveals Salmonella Kedougou as a major cause of human infections in northern Thailand especially during the hot period and suggests a global spread probably due to travel. The clonal...... types causing infections in humans differed from those observed in animals in United Kingdom, which suggests the absence of an epidemiological link and could suggest differences in virulence. The high frequency of antimicrobial resistance, including emergence of resistance to fluoroquinolones and third...

  18. Factors influencing Salmonella carcass prevalence in Danish pig abattoirs

    DEFF Research Database (Denmark)

    Freitas de Matos Baptista, Filipa; Dahl, J.; Nielsen, Liza Rosenbaum

    2010-01-01

    The Danish Salmonella Surveillance-and-Control Programme in finisher pigs includes both herd and carcass surveillance. Herd surveillance consists of serological testing of meat-juice samples and classification of herds into three Salmonella seroprevalence levels. At the abattoirs, carcass swabs...... from five pigs are collected daily and analysed as a pooled sample to evaluate the Salmonella carcass prevalence. This study aimed to investigate factors associated with Salmonella carcass prevalence in Denmark. A total of 20,196 pooled carcass swabs collected in 23 Danish abattoirs were included...... in the analysis. A multilevel logistic regression model was used taking into account the two-level data structure (abattoir, carcass pool) and adjusting the parameter estimates to the random variation at the abattoir level. Study results indicated that carcass contamination was mainly influenced...

  19. Fructose Mediated Non-Alcoholic Fatty Liver Is Attenuated by HO-1-SIRT1 Module in Murine Hepatocytes and Mice Fed a High Fructose Diet.

    Directory of Open Access Journals (Sweden)

    Komal Sodhi

    Full Text Available Oxidative stress underlies the etiopathogenesis of nonalcoholic fatty liver disease (NAFLD, obesity and cardiovascular disease (CVD. Heme Oxygenase-1 (HO-1 is a potent endogenous antioxidant gene that plays a key role in decreasing oxidative stress. Sirtuin1 (SIRT1 belongs to the family of NAD-dependent de-acyetylases and is modulated by cellular redox.We hypothesize that fructose-induced obesity creates an inflammatory and oxidative environment conducive to the development of NAFLD and metabolic syndrome. The aim of this study is to determine whether HO-1 acts through SIRT1 to form a functional module within hepatocytes to attenuate steatohepatitis, hepatic fibrosis and cardiovascular dysfunction.We examined the effect of fructose, on hepatocyte lipid accumulation and fibrosis in murine hepatocytes and in mice fed a high fructose diet in the presence and absence of CoPP, an inducer of HO-1, and SnMP, an inhibitor of HO activity. Fructose increased oxidative stress markers and decreased HO-1 and SIRT1 levels in hepatocytes (p<0.05. Further fructose supplementation increased FAS, PPARα, pAMPK and triglycerides levels; CoPP negated this increase. Concurrent treatment with CoPP and SIRT1 siRNA in hepatocytes increased FAS, PPARα, pAMPK and triglycerides levels suggesting that HO-1 is upstream of SIRT1 and suppression of SIRT1 attenuates the beneficial effects of HO-1. A high fructose diet increased insulin resistance, blood pressure, markers of oxidative stress and lipogenesis along with fibrotic markers in mice (p<0.05. Increased levels of HO-1 increased SIRT1 levels and ameliorated fructose-mediated lipid accumulation and fibrosis in liver along with decreasing vascular dysfunction (p<0.05 vs. fructose. These beneficial effects of CoPP were reversed by SnMP.Taken together, our study demonstrates, for the first time, that HO-1 induction attenuates fructose-induced hepatic lipid deposition, prevents the development of hepatic fibrosis and abates

  20. Characterization of Salmonella enterica Ituri isolated from diseased ...

    African Journals Online (AJOL)

    User

    2013-04-17

    Apr 17, 2013 ... Salmonella enterica Ituri is an uncommon serotype associated with poultry disease. One of the serotype isolated from a poultry disease in Nigeria was characterized by serotyping and screening for the presence of Salmonella genomic island 1(SGI1) as a possible factor responsible for its involvement.

  1. Molecular and biochemical diagnosis of Salmonella in wastewater ...

    African Journals Online (AJOL)

    This study aimed to employ biochemical and molecular assays to detect and diagnose Salmonella in wastewater. For this reason, two water samples were collected from Alexandria wastewater treatment plant (S1) and septic tank of a hospital at Alexandria governorate (S2). Selective culture media specific for Salmonella ...

  2. Serological prevalence and associated risk factors of Salmonella ...

    African Journals Online (AJOL)

    ... to identify risk factors associated with Salmonella infections in chickens. The overall sero-prevalence established using serum plate agglutination test was 16.7% (98/588). Using a univariate logistic analysis, factors significantly associated with Salmonella infections at p < 0.05 were presence of other birds in poultry farms ...

  3. Detection and classification of salmonella serotypes using spectral signatures collected by fourier transform infrared (FT-IR) spectroscopy

    Science.gov (United States)

    Spectral signatures of Salmonella serotypes namely Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky were collected using Fourier transform infrared spectroscopy (FT-IR). About 5-10 µL of Salmonella suspensions with concentrations of 1...

  4. Characterization and Antimicrobial Resistance of Salmonella Typhimurium Isolates from Clinically Diseased Pigs in Korea.

    Science.gov (United States)

    Oh, Sang-Ik; Kim, Jong Wan; Chae, Myeongju; Jung, Ji-A; So, Byungjae; Kim, Bumseok; Kim, Ha-Young

    2016-11-01

    This study investigated the prevalence of Salmonella enterica serovar and antimicrobial resistance in Salmonella Typhimurium isolates from clinically diseased pigs collected from 2008 to 2014 in Korea. Isolates were also characterized according to the presence of antimicrobial resistance genes and pulsed-field gel electrophoresis patterns. Among 94 Salmonella isolates, 81 (86.2%) were identified as being of the Salmonella Typhimurium serotype, followed by Salmonella Derby (6 of 94, 6.4%), Salmonella 4,[5],12:i:- (4 of 94, 4.3%), Salmonella Enteritidis (2 of 94, 2.1%), and Salmonella Brandenburg (1 of 94, 1.1%). The majority of Salmonella Typhimurium isolates were resistant to tetracycline (92.6%), followed by streptomycin (88.9%) and ampicillin (80.2%). Overall, 96.3% of Salmonella Typhimurium isolates showed multidrug-resistant phenotypes and commonly harbored the resistance genes bla TEM (64.9%), flo (32.8%), aadA (55.3%), strA (58.5%), strB (58.5%), sulII (53.2%), and tetA (61.7%). The pulsed-field gel electrophoresis analysis of 45 Salmonella Typhimurium isolates from individual farms revealed 27 distinct patterns that formed one major and two minor clusters in the dendrogram analysis, suggesting that most of the isolates (91.1%) from diseased pigs were genetically related. These findings can assist veterinarians in the selection of appropriate antimicrobial agents to combat Salmonella Typhimurium infections in pigs. Furthermore, they highlight the importance of continuous surveillance of antimicrobial resistance and genetic status in Salmonella Typhimurium for the detection of emerging resistance trends.

  5. FNDC5 attenuates adipose tissue inflammation and insulin resistance via AMPK-mediated macrophage polarization in obesity.

    Science.gov (United States)

    Xiong, Xiao-Qing; Geng, Zhi; Zhou, Bing; Zhang, Feng; Han, Ying; Zhou, Ye-Bo; Wang, Jue-Jin; Gao, Xing-Ya; Chen, Qi; Li, Yue-Hua; Kang, Yu-Ming; Zhu, Guo-Qing

    2018-06-01

    Obesity-induced chronic inflammation is critical in the pathogenesis of insulin resistance, and the recruitment and proinflammatory activation of adipose tissue macrophages (ATMs) is important for the development of this process. Here, we examined the effects of fibronectin type III domain-containing 5 (FNDC5) on inflammation and insulin resistance in high-fat diet-induced obese mice. Male wild-type (WT) and FNDC5 -/- mice were fed with standard chow (Ctrl) or high fat diet (HFD) for 20 weeks to induce obesity and insulin resistance. Firstly, effects of FNDC5 gene deletion on obesity, insulin resistance, macrophage accumulation and polarization and adipose tissue inflammation were determined in mice. Secondly, the macrophage polarity shift was further examined with flow cytometry in isolated stromal vascular fraction (SVF). Thirdly, the effects of exogenous FNDC5 on lipopolysaccharide (LPS)-induced macrophage polarization, inflammation and the underlying signaling mechanism were investigated in RAW264.7 macrophages and primary mouse peritoneal cavity macrophages (PMs). Finally, the therapeutic effects of FNDC5 overexpression were examined in HFD-induced obese WT and FNDC5 -/- mice. FNDC5 gene deletion aggravated obesity, insulin resistance, fat accumulation and inflammation accompanied with enhanced AMPK inhibition, macrophages recruitment and M1 polarization in mice fed with HFD. Exogenous FNDC5 inhibited LPS-induced M1 macrophage polarization and inflammatory cytokine production via AMPK phosphorylation in both RAW264.7 macrophages and PMs. FNDC5 overexpression attenuated insulin resistance, AMPK inhibition, M1 macrophage polarization and inflammatory cytokine production in adipose tissue of obese WT and FNDC5 -/- mice. FNDC5 attenuates adipose tissue inflammation and insulin resistance via AMPK-mediated macrophage polarization in HFD-induced obesity. FNDC5 plays several beneficial roles in obesity and may be used as a therapeutic regimen for preventing

  6. Drug resistant Salmonella in broiler chicken sold at local market in ...

    African Journals Online (AJOL)

    This study was designed to isolate and identify Salmonella spp. from cloacal swabs of apparently healthy broiler chickens in Bangladesh. Salmonella was characterized culturally, biochemically and also via PCR method. Among 50 isolates, 16 were found to be positive for Salmonella. PCR using 16S rRNA gene primers ...

  7. Salmonella serovar-specific interaction with jejunal epithelial cells.

    Science.gov (United States)

    Razzuoli, Elisabetta; Amadori, Massimo; Lazzara, Fabrizio; Bilato, Dania; Ferraris, Monica; Vito, Guendalina; Ferrari, Angelo

    2017-08-01

    Gut is often a receptacle for many different pathogens in feed and/or the environment, such as Salmonella spp. The current knowledge about pathogenicity of Salmonella is restricted to few serotypes, whereas other important ones like S. Coeln, S. Thompson, S. Veneziana, have not been investigated yet in human and animal models. Therefore, the aim of our work was to verify the ability of widespread environmental Salmonella strains to penetrate and modulate innate immunity in pig intestinal IPEC-J2 cells. Our results outline the different ability of Salmonella strains to modulate innate immunity; the expression of the IFN-β gene was increased by S. Typhimurium, S. Ablogame and S. Diarizonae 2, that also caused an inflammatory response in terms of Interleukin (IL)-1β and/or IL-8 gene espression. In particular, IL-8 gene expression and protein release were significantly modulated by 5 Salmonella strains out of 7. Interestingly, S. Typhimurium, S. Coeln and S. Thompson strains, characterized by a peculiar ability to penetrate into IPEC-J2 cells, up-regulated both IL-8 and TNF-α gene expression. Accordingly, blocking IL-8 was shown to decrease the penetration of S. Typhimurium. On the contrary, S. Diarizonae strain 1, showing lesser invasion of IPEC-J2 cells, down-regulated the p38-MAPK pathway, and it did not induce an inflammatory response. Our results confirm that IPEC-J2 cells are a useful model to evaluate host-gut pathogen interaction and indicate IL-8 and TNF-α as possible predictive markers of invasiveness of Salmonella strains in enterocytes. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Experimental reproduction of rotavirus and Salmonella pullorum ...

    African Journals Online (AJOL)

    Group A chicks were inoculated with 1 X 106 pfu/ml of rotavirus, group B chicks were inoculated with 1 X 106 cfu/ml of Salmonella pullorum, group C chicks were inoculated with 1 X 106 pfu/ml of rotavirus and 1 X 106 cfu/ml of Salmonella pullorum, while group D birds were given 1ml of PBS alone. Birds in all groups were ...

  9. Salmonella Urinary Tract Infection Heralding Thoracic Mycotic Aneurysm: Case Report as Medical Apology

    Science.gov (United States)

    White, Jennifer L.; Golfus, Gabriel R.; Sadosty, Annie T.

    2017-01-01

    We report a case as a patient apology as a means of teaching other physicians about a unique presentation of a rare disease. Salmonella species are unusually isolated organisms in urine. In the case described, appreciation for the rarity of Salmonella species in the urine facilitated recognition of a serious disseminated Salmonella infection. Physicians should consider disseminated Salmonella infection, as was found in a patient with an aortic mycotic an eurysm, after isolation of Salmonella in urine despite an initially benign clinical presentation.

  10. Salmonella contamination of hatching and table eggs: a comparison.

    OpenAIRE

    Poppe, C; Duncan, C L; Mazzocco, A

    1998-01-01

    This study determined and compared Salmonella contamination rates of pools of surplus, early and culled hatching eggs from layer and broiler breeder flocks, and of pools of early and regular table eggs from layer flocks. Each pool contained 6 eggs. Five methods were used for the isolation of Salmonella. Nine of 126 pools of culled layer hatching eggs, 2 of 126 pools of surplus layer hatching eggs, and one of 126 pools of early layer hatching eggs were contaminated with Salmonella. All 126 poo...

  11. Use of enrichment real-time PCR to enumerate salmonella on chicken parts.

    Science.gov (United States)

    Oscar, T P

    2014-07-01

    Salmonella bacteria that survive cooking or that cross-contaminate other food during meal preparation and serving represent primary routes of consumer exposure to this pathogen from chicken. In the present study, enrichment real-time PCR (qPCR) was used to enumerate Salmonella bacteria that contaminate raw chicken parts at retail or that cross-contaminate cooked chicken during simulated meal preparation and serving. Whole raw chickens obtained at retail were partitioned into wings, breasts, thighs, and drumsticks using a sterilized knife and cutting board, which were then used to partition a cooked chicken breast to assess cross-contamination. After enrichment in buffered peptone water (400 ml, 8 h, 40°C, 80 rpm), subsamples were used for qPCR and cultural isolation of Salmonella. In some experiments, chicken parts were spiked with 0 to 3.6 log of Salmonella Typhimurium var. 5- to generate a standard curve for enumeration by qPCR. Of 10 raw chickens examined, 7 (70%) had one or more parts contaminated with Salmonella. Of 80 raw parts examined, 15 (19%) were contaminated with Salmonella. Of 20 cooked chicken parts examined, 2 (10%) were cross-contaminated with Salmonella. Predominant serotypes identified were Typhimurium (71%) and its variants (var. 5-, monophasic, and nonmotile) and Kentucky (18%). The number of Salmonella bacteria on contaminated parts ranged from one to two per part. Results of this study indicated that retail chicken parts examined were contaminated with low levels of Salmonella, which resulted in low levels of cross-contamination during simulated meal preparation and serving. Thus, if consumers properly handle and prepare the chicken, it should pose no or very low risk of consumer exposure to Salmonella.

  12. Detection of Salmonella enterica Serovar Typhimurium from Avians Using Multiplex-PCR

    Directory of Open Access Journals (Sweden)

    Alireza Talebi

    2011-09-01

    Full Text Available Abstract Salmonella enterica serovar Typhimurium and S.enterica serovar Enteritidis are the most frequently isolated serovars from food-borne diseases throughout the world. According to their antigenic profiles, salmonella shows different disease syndromes and host specificities. It is necessary and important to discriminate salmonella serovars from each other in order to ensure that each pathogen and its epidemiology are correctly recognized. Many PCR-based methods have been developed to identify salmonella serovars. The objective of present study was to identify S. Typhimurium in avians from different regions including: North, Northwest and capital city (Tehran of Iran. Also in this research, the quality of CHROMagar™ Salmonella medium (CAS medium in veterinary medicine was evaluated. The results of present study showed that out of 1870 intestine samples, fifty two S. Typhimurium including broiler (n=13, layer (n=12, duck (n=5, goose (n=5, sparrow (n=8, canary (n=3, pigeon (n=5 and African grey parrot (n=1 were identified using serotyping as well as multiplex-PCR. In conclusion, important measures must be taken on prevention and propagation of S. Typhimurium among avians. CHROMagar™ Salmonella medium has high levels of sensitivity and specificity and reduced the time to final identification of salmonella spp. in comparison with biochemical tests.

  13. Diagnosis of Salmonella Enteritidis Infection in Broiler Chickens ...

    African Journals Online (AJOL)

    Diagnosis of Salmonella Enteritidis Infection in Broiler Chickens Using Elisa. ES Soliman, E Taha, WS Abdella, C KilPatrick, AN Wise, MAA Sobieh, PG Reddy. Abstract. The program for the eradication of Salmonella Enteritidis from chickens was based on bacteriological examination of breeding flocks. There is a great need ...

  14. Characterization of Salmonella enterica Ituri isolated from diseased ...

    African Journals Online (AJOL)

    Salmonella enterica Ituri is an uncommon serotype associated with poultry disease. One of the serotype isolated from a poultry disease in Nigeria was characterized by serotyping and screening for the presence of Salmonella genomic island 1(SGI1) as a possible factor responsible for its involvement in a poultry disease ...

  15. Multidrug resistant Salmonellae isolated from blood culture samples ...

    African Journals Online (AJOL)

    This study investigates the prevalence of R-plasmids in Salmonella sp. isolated from blood samples of suspected typhoid patients in Warri, Nigeria. A total of 136 blood samples were collected between May and December,2009 and screened for the presence of Salmonellae using standard blood culture techniques of which ...

  16. Elicitation of expert knowledge on controlling Salmonella in the pork chain

    NARCIS (Netherlands)

    Gaag, v.d. M.; Huirne, R.B.M.

    2002-01-01

    Salmonella is one of the most important risks for food safety, and pork is one of the sources of human salmonellosis. A chain approach is essential to reduce Salmonella in pork products. A survey was carried out among Dutch and Danish experts in the field of Salmonella to evaluate the entire pork

  17. Preliminary findings of Salmonella spp. in captive green iguanas (Iguana iguana) and their environment.

    Science.gov (United States)

    Mitchell, M A; Shane, S M

    2000-06-12

    Captive reptiles are routinely identified as reservoirs of Salmonella spp. and reports of reptile-associated salmonellosis are increasing. Unfortunately, little is known about the epidemiology of Salmonella spp. and green iguanas. We did a limited survey of a green-iguana farm in El Salvador to identify sources of Salmonella spp. in green iguanas and their environment. A limited number of samples for microbiological culture were collected from iguanas (adult, hatchling, and embryos) and their environment (food, water, soil, shelter, insects, and wild-caught lizards). Salmonella spp. was isolated from the intestine of both adult (3/20) and hatchling iguanas (8/20). There was no evidence of Salmonella spp. in the reproductive tracts of female iguanas (0/10). Salmonella spp. was isolated from the surface of 40% (7/16) of the egg surfaces tested. Salmonella spp. was not identified from the externalized yolk-sac of the iguana embryos tested. Soil samples from a breeding pen and a nest were both positive for Salmonella spp. Eight different Salmonella spp. serotypes were identified in this survey. These results suggest that horizontal transmission of Salmonella spp. is a potential source of exposure to hatchling iguanas at this facility.

  18. Factors associated with fecal-shedding of Salmonella spp by horses on US operations

    Directory of Open Access Journals (Sweden)

    Losinger W.C.

    2002-01-01

    Full Text Available In a cross-sectional national study that included 972 operations with > 3 horses on 1/1/98 in 28 states in the USA, 8,417 fecal specimens were collected from horses and cultured to test for the presence of Salmonella spp. Operations were characterized as Salmonella spp-positive if at least one fecal specimen tested positive for Salmonella spp. Percentages of Salmonella spp-positive operations were computed by management and other factors (collected from operation-level questionnaires that were hypothesized to be related to fecal shedding of Salmonella spp. A logistic-regression model was constructed to identify factors associated with horses? shedding Salmonella spp in feces on an operation. The odds of an operation being Salmonella spp positive increased as the number of resident horses increased. In addition, the following factors were found to be associated with increased odds of an operation being Salmonella spp positive: horses were used primarily for breeding; operation cleanliness was characterized as poor by the data collector; and new resident equids had been added to the operation without routine quarantine.

  19. Dynamics of Salmonella Shedding and Welfare of Hens in Free-Range Egg Production Systems

    Science.gov (United States)

    Gole, Vaibhav C.; Woodhouse, Rebecca; Caraguel, Charles; Moyle, Talia; Rault, Jean-Loup; Sexton, Margaret

    2016-01-01

    ABSTRACT The current study investigated the effect of environmental stressors (i.e., weather changes) on Salmonella shedding in free-range production systems and the correlations with behavioral and physiological measures (i.e., fecal glucocorticoid metabolites). This involved longitudinal and point-in-time surveys of Salmonella shedding and environmental contamination on four commercial free-range layer farms. The shedding of Salmonella was variable across free-range farms and in different seasons. There was no significant effect of season on the Salmonella prevalence during this investigation. In this study, the combined Salmonella most probable number (MPN) counts in environmental (including feces, egg belt, dust, nest box, and ramp) samples were highest in samples collected during the summer season (4th sampling, performed in February). The predominant serovars isolated during this study were Salmonella enterica serovar Mbandaka and Salmonella enterica serovar Typhimurium phage types 135 and 135a. These two phage types were involved in several egg product-related Salmonella outbreaks in humans. Multilocus variable-number tandem-repeat analysis (MLVA) results indicated that MLVA types detected from human food poisoning cases exhibited MLVA patterns similar to the strains isolated during this study. All Salmonella isolates (n = 209) were tested for 15 different genes involved in adhesion, invasion, and survival of Salmonella spp. We also observed variations for sopA, ironA, and misL. There were no positive correlations between fecal corticosterone metabolite (FCM) and Salmonella prevalence and/or shedding in feces. Also, there were no positive correlations between Salmonella prevalence and Salmonella count (log MPN) and any of the other welfare parameters. IMPORTANCE In this study, the welfare of laying hens and Salmonella shedding were compared over a prolonged period of time in field conditions. This study investigated the long-term shedding of Salmonella

  20. Dynamics of Salmonella Shedding and Welfare of Hens in Free-Range Egg Production Systems.

    Science.gov (United States)

    Gole, Vaibhav C; Woodhouse, Rebecca; Caraguel, Charles; Moyle, Talia; Rault, Jean-Loup; Sexton, Margaret; Chousalkar, Kapil

    2017-03-01

    The current study investigated the effect of environmental stressors (i.e., weather changes) on Salmonella shedding in free-range production systems and the correlations with behavioral and physiological measures (i.e., fecal glucocorticoid metabolites). This involved longitudinal and point-in-time surveys of Salmonella shedding and environmental contamination on four commercial free-range layer farms. The shedding of Salmonella was variable across free-range farms and in different seasons. There was no significant effect of season on the Salmonella prevalence during this investigation. In this study, the combined Salmonella most probable number (MPN) counts in environmental (including feces, egg belt, dust, nest box, and ramp) samples were highest in samples collected during the summer season (4th sampling, performed in February). The predominant serovars isolated during this study were Salmonella enterica serovar Mbandaka and Salmonella enterica serovar Typhimurium phage types 135 and 135a. These two phage types were involved in several egg product-related Salmonella outbreaks in humans. Multilocus variable-number tandem-repeat analysis (MLVA) results indicated that MLVA types detected from human food poisoning cases exhibited MLVA patterns similar to the strains isolated during this study. All Salmonella isolates ( n = 209) were tested for 15 different genes involved in adhesion, invasion, and survival of Salmonella spp. We also observed variations for sopA , ironA , and misL There were no positive correlations between fecal corticosterone metabolite (FCM) and Salmonella prevalence and/or shedding in feces. Also, there were no positive correlations between Salmonella prevalence and Salmonella count (log MPN) and any of the other welfare parameters. IMPORTANCE In this study, the welfare of laying hens and Salmonella shedding were compared over a prolonged period of time in field conditions. This study investigated the long-term shedding of Salmonella serovars in

  1. Oral DNA Vaccine in Chickens

    Directory of Open Access Journals (Sweden)

    Seyed Davoud Jazayeri

    2012-01-01

    Full Text Available Attenuated Salmonella has been used as a carrier for DNA vaccine. However, in vitro and in vivo studies on the bacteria following transfection of plasmid DNA were poorly studied. In this paper, eukaryotic expression plasmids encoding avian influenza virus (AIV subtype H5N1 genes, pcDNA3.1/HA, NA, and NP, were transfected into an attenuated Salmonella enteric typhimurium SV4089. In vitro stability of the transfected plasmids into Salmonella were over 90% after 100 generations. The attenuated Salmonella were able to invade MCF-7 (1.2% and MCF-10A (0.5% human breast cancer cells. Newly hatched specific-pathogen-free (SPF chicks were inoculated once by oral gavage with 109 colony-forming unit (CFU of the attenuated Salmonella. No abnormal clinical signs or deaths were recorded after inoculation. Viable bacteria were detected 3 days after inoculation by plating from spleen, liver, and cecum. Fluorescent in situ hybridization (FISH and polymerase chain reaction (PCR were carried out for confirmation. Salmonella was not detected in blood cultures although serum antibody immune responses to Salmonella O antiserum group D1 factor 1, 9, and 12 antigens were observed in all the inoculated chickens after 7 days up to 35 days. Our results showed that live attenuated S. typhimurium SV4089 harboring pcDNA3.1/HA, NA, and NP may provide a unique alternative as a carrier for DNA oral vaccine in chickens.

  2. Diversification of the Salmonella fimbriae: a model of macro- and microevolution.

    Directory of Open Access Journals (Sweden)

    Min Yue

    Full Text Available Bacteria of the genus Salmonella comprise a large and evolutionary related population of zoonotic pathogens that can infect mammals, including humans and domestic animals, birds, reptiles and amphibians. Salmonella carries a plethora of virulence genes, including fimbrial adhesins, some of them known to participate in mammalian or avian host colonization. Each type of fimbria has its structural subunit and biogenesis genes encoded by one fimbrial gene cluster (FGC. The accumulation of new genomic information offered a timely opportunity to better evaluate the number and types of FGCs in the Salmonella pangenome, to test the use of current classifications based on phylogeny, and to infer potential correlations between FGC evolution in various Salmonella serovars and host niches. This study focused on the FGCs of the currently deciphered 90 genomes and 60 plasmids of Salmonella. The analysis highlighted a fimbriome consisting of 35 different FGCs, of which 16 were new, each strain carrying between 5 and 14 FGCs. The Salmonella fimbriome was extremely diverse with FGC representatives in 8 out of 9 previously categorized fimbrial clades and subclades. Phylogenetic analysis of Salmonella suggested macroevolutionary shifts detectable by extensive FGC deletion and acquisition. In addition, microevolutionary drifts were best depicted by the high level of allelic variation in predicted or known adhesins, such as the type 1 fimbrial adhesin FimH for which 67 different natural alleles were identified in S. enterica subsp. I. Together with strain-specific collections of FGCs, allelic variation among adhesins attested to the pathoadaptive evolution of Salmonella towards specific hosts and tissues, potentially modulating host range, strain virulence, disease progression, and transmission efficiency. Further understanding of how each Salmonella strain utilizes its panel of FGCs and specific adhesin alleles for survival and infection will support the

  3. Diversification of the Salmonella Fimbriae: A Model of Macro- and Microevolution

    Science.gov (United States)

    Yue, Min; Rankin, Shelley C.; Blanchet, Ryan T.; Nulton, James D.; Edwards, Robert A.; Schifferli, Dieter M.

    2012-01-01

    Bacteria of the genus Salmonella comprise a large and evolutionary related population of zoonotic pathogens that can infect mammals, including humans and domestic animals, birds, reptiles and amphibians. Salmonella carries a plethora of virulence genes, including fimbrial adhesins, some of them known to participate in mammalian or avian host colonization. Each type of fimbria has its structural subunit and biogenesis genes encoded by one fimbrial gene cluster (FGC). The accumulation of new genomic information offered a timely opportunity to better evaluate the number and types of FGCs in the Salmonella pangenome, to test the use of current classifications based on phylogeny, and to infer potential correlations between FGC evolution in various Salmonella serovars and host niches. This study focused on the FGCs of the currently deciphered 90 genomes and 60 plasmids of Salmonella. The analysis highlighted a fimbriome consisting of 35 different FGCs, of which 16 were new, each strain carrying between 5 and 14 FGCs. The Salmonella fimbriome was extremely diverse with FGC representatives in 8 out of 9 previously categorized fimbrial clades and subclades. Phylogenetic analysis of Salmonella suggested macroevolutionary shifts detectable by extensive FGC deletion and acquisition. In addition, microevolutionary drifts were best depicted by the high level of allelic variation in predicted or known adhesins, such as the type 1 fimbrial adhesin FimH for which 67 different natural alleles were identified in S. enterica subsp. I. Together with strain-specific collections of FGCs, allelic variation among adhesins attested to the pathoadaptive evolution of Salmonella towards specific hosts and tissues, potentially modulating host range, strain virulence, disease progression, and transmission efficiency. Further understanding of how each Salmonella strain utilizes its panel of FGCs and specific adhesin alleles for survival and infection will support the development of new approaches

  4. Sensitivitas Salmonella Sp. Penyebab Demam Tifoid Terhadap Beberapa Antibiotik di Rumah Sakit Immanuel Bandung

    Directory of Open Access Journals (Sweden)

    Yanti Mulyana

    2009-09-01

    Full Text Available Typhoid fever is an enteric fever caused by Salmonella sp. especially Salmonella typhi and Salmonella paratyphi. Various antibiotics used for therapy beside chloramphenicol as drug of choice. Non rational use of antibiotics may result increasing of resistence in bacteria. The aim of the research is to know the sensitivity of Salmonella typhi and Salmonella paratyphi to some antibiotics. The purpose is to gather information about antibiotics which are still effective for typhoid fever and enteric therapy. Salmonella typhi and Salmonella paratyphi strain from positive cultures diagnose typhoid fever patients at Immanuel Hospital Bandung during 2004-2007. The method of resistance is Kirby Bauer's disk diffusion assay with NCCLS standard. The disk antibiotics used are amoxicillin, amoxicillinclavulanic acid, chloramphenicol, ciprofloxacin, ceftriaxone, trimethoprim, and trimethoprim-sulfamethoxazole. The result showed penicillin group, amoxicillin and amoxicillin-clavulanic acid had 96.3–99.68% sensitive against Salmonella sp. Sensitivity of chloramphenicol as drug of choice of typhoid fever still 99.05%. Since the sensitivity less than 100%, it means there was about 8% resistence. Thats why eventhough this data can be used as empiric therapy, the writer suggest to do sensitivity test to Salmonella sp. that caused typhoid to get rationally dan effective treatment. From the result, it's concluded that Salmonella typhi and Salmonella paratyphi are still sensitive to all that antibiotics.

  5. Plasmid fingerprinting and virulence gene detection among indigenous strains of salmonella enterica serovar enteritidis

    International Nuclear Information System (INIS)

    Sajid, S.U.; Schwarz, S.

    2009-01-01

    Salmonella enterica serovar Enteritidis is an important frequently reported zoonotic pathogen and a common cause of human gastroenteritis worldwide. The highly conserved Serospecific plasmids (SSPs) and Salmonella plasmid virulence (Spv) genes have been shown to mediate extra-intestinal colonization and systemic infection. The objective of current study was to document the presence of SSPs and SpvB/SpvC genes prevailing in the indigenous population of serovar Enteritidis. A total of 48 epidemiologically unrelated strains of Salmonella enteritidis were included in the study. Preparation of plasmids DNA suitable for endonuclease digestion and separation of respective fragments by agarose gel electrophoresis followed previously described protocols. The plasmids of Escherichia coli V517, 1-kbp ladder, and lambda DNA HindIII fragments served as DNA size standards. Transfer of DNA fragments from agarose gels to nitrocellulose membranes was achieved by capillary blot procedure. An ECL labeled 3.6 kbp HindIII fragment of plasmid PRQ 51 was used as probe for SpvB/SpvC gene detection. Plasmid DNA fingerprinting revealed the presence of two different profiles of approximately 55 kbp and 90 kbp and were identified as virulence plasmids by DNA hybridization. The SpvB/SpvC genes were located on HindIII fragments of 3.6 kbp in each of the two types of virulence plasmids. The study confirms the presence of SSPs and SpvB/SpvC genes in indigenous strains of S. enteritidis isolated from Northern Punjab area of Pakistan and substantiate the previous data on such findings from other parts of the world. (author)

  6. Prevalence of salmonella infection in dogs in maiduguri, northeastern Nigeria.

    Science.gov (United States)

    Jajere, Saleh Mohammed; Onyilokwu, Samson Amali; Adamu, Nuhu Bala; Atsanda, Naphtali Nayamanda; Saidu, Adamu Saleh; Adamu, Shuaibu Gidado; Mustapha, Fatima Bukar

    2014-01-01

    The prevalence and antimicrobial sensitivity of Salmonella from dogs in Maiduguri Metropolis were determined using standard bacteriological methods to assess the risk of possible transmission of Salmonella infection from dogs to humans. Of 119 samples, Salmonella was isolated from 52 (43.7%). Males had higher prevalence of 50.0% compared with 34.7% in females (P < 0.05). Dogs older than 24 months had higher prevalence of 61.0% and the lowest was seen in dogs aged 13-24 months (P < 0.05). The prevalence of 31.8%, 41.2%, and 58.8% was observed in dogs aged 3-6, 10-12, and 7-9 months, respectively. High prevalence of 49.5% was observed in Mongrels, while Terrier and Alsatian breeds had 30.0% and 8.3%, respectively. Salmonella isolates from Alsatian and Terrier breeds showed about 100% susceptibility to all the tested antimicrobials. Higher percentage of the Salmonella isolates from Mongrels also showed susceptibility to ciprofloxacin (89.7%), amoxicillin (87.6%), vancomycin (86.6%), and chloramphenicol (84.5%). However about 50% of these isolates showed resistance to ofloxacin. The carrier status of Salmonella is high among dogs especially Mongrels. Therefore good environmental hygiene, discouraging straying coupled with feeding of dogs with properly cooked and uncontaminated feeds was recommended to mitigate risk of human salmonellosis.

  7. Evanescent Wave Fiber Optic Biosensor for Salmonella Detection in Food

    Directory of Open Access Journals (Sweden)

    Arun K. Bhunia

    2009-07-01

    Full Text Available Salmonella enterica is a major food-borne pathogen of world-wide concern. Sensitive and rapid detection methods to assess product safety before retail distribution are highly desirable. Since Salmonella is most commonly associated with poultry products, an evanescent wave fiber-optic assay was developed to detect Salmonella in shell egg and chicken breast and data were compared with a time-resolved fluorescence (TRF assay. Anti-Salmonella polyclonal antibody was immobilized onto the surface of an optical fiber using biotin-avidin interactions to capture Salmonella. Alexa Fluor 647-conjugated antibody (MAb 2F-11 was used as the reporter. Detection occurred when an evanescent wave from a laser (635 nm excited the Alexa Fluor and the fluorescence was measured by a laser-spectrofluorometer at 710 nm. The biosensor was specific for Salmonella and the limit of detection was established to be 103 cfu/mL in pure culture and 104 cfu/mL with egg and chicken breast samples when spiked with 102 cfu/mL after 2–6 h of enrichment. The results indicate that the performance of the fiber-optic sensor is comparable to TRF, and can be completed in less than 8 h, providing an alternative to the current detection methods.

  8. Transcriptional changes of cytokines in rooster testis and epididymis during sexual maturation stages and Salmonella infection.

    Science.gov (United States)

    Anastasiadou, M; Michailidis, G

    2016-08-01

    Infection of rooster testis and epididymis by pathogens can lead to impaired fertility, resulting in economic losses in the poultry industry. Antimicrobial protection of rooster reproductive organs is, therefore, an important aspect of reproductive physiology. Salmonellosis is one of the most important zoonotic diseases, caused by Salmonella bacteria including Salmonella Enteritidis (SE) and is usually the result of infection of the reproductive organs. Thus, knowledge of the endogenous innate immune mechanisms of the rooster testis and epididymis is an emerging aspect of reproductive physiology. Cytokines are key factors for stimulating the immune response and inflammation in chickens to Salmonella infection. In the present study the expression profile of 11 pro-inflammatory cytokine genes in the rooster testis and epididymis in vivo and transcriptional changes in these organs during sexual maturation and SE infection were investigated. Gene expression analysis data revealed that in both testis and epididymis nine cytokines namely the IL-1β, IL-6, IL-8, IL-10, IL-12, IL-15, IL-16, IL-17 and IL-18 genes were expressed, while no mRNA transcripts were detected in both organs for IL-2 and IL-4. Furthermore, the expression of various cytokine genes during sexual maturation appeared to be developmentally regulated, while SE infection resulted in a significant up-regulation of IL-1β, -6, -12 and -18 genes in the testis and an increase in the mRNA relative abundance of IL-1β, -6, -12, -16 and -18 in the epididymis of SE-infected sexually mature 28-week-old roosters. These results suggest a cytokine-mediated immune response mechanism against Salmonella infection in the rooster reproductive tract. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Cyclooxygenase inhibitors attenuate bradykinin-induced vasoconstriction in septic isolated rat lungs

    NARCIS (Netherlands)

    Fischer, L. G.; Hollmann, M. W.; Horstman, D. J.; Rich, G. F.

    2000-01-01

    Cyclooxygenase (COX) products play an important role in modulating sepsis and subsequent endothelial injury. We hypothesized that COX inhibitors may attenuate endothelial dysfunction during sepsis, as measured by receptor-mediated bradykinin (BK)-induced vasoconstriction and/or receptor-independent

  10. A Phylogenetic and Phenotypic Analysis of Salmonella enterica Serovar Weltevreden, an Emerging Agent of Diarrheal Disease in Tropical Regions.

    Directory of Open Access Journals (Sweden)

    Carine Makendi

    2016-02-01

    Full Text Available Salmonella enterica serovar Weltevreden (S. Weltevreden is an emerging cause of diarrheal and invasive disease in humans residing in tropical regions. Despite the regional and international emergence of this Salmonella serovar, relatively little is known about its genetic diversity, genomics or virulence potential in model systems. Here we used whole genome sequencing and bioinformatics analyses to define the phylogenetic structure of a diverse global selection of S. Weltevreden. Phylogenetic analysis of more than 100 isolates demonstrated that the population of S. Weltevreden can be segregated into two main phylogenetic clusters, one associated predominantly with continental Southeast Asia and the other more internationally dispersed. Subcluster analysis suggested the local evolution of S. Weltevreden within specific geographical regions. Four of the isolates were sequenced using long read sequencing to produce high quality reference genomes. Phenotypic analysis in Hep-2 cells and in a murine infection model indicated that S. Weltevreden were significantly attenuated in these models compared to the classical S. Typhimurium reference strain SL1344. Our work outlines novel insights into this important emerging pathogen and provides a baseline understanding for future research studies.

  11. A PCR-based strategy for simple and rapid identification of rough presumptive Salmonella isolates

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Baggesen, Dorte Lau; Porting, P.H.

    1999-01-01

    The purpose of the present study was to investigate the application of ready-to-go Salmonella PCR tests, based on dry chemistry, for final identification of rough presumptive Salmonella isolates. The results were compared with two different biotyping methods performed at two different laboratories......, which did not result in any DNA band. A total of 32 out of the 36 rough presumptive isolates were positive in the PCR. All but one isolate were also identified as Salmonella by the two biochemical methods. All 80 Salmonella strains were also tested in the two multiplex serogroup tests based on PCR beads....... The sensitivity of the BAX Salmonella PCR test was assessed by testing a total of 80 Salmonella isolates, covering most serogroups, which correctly identified all the Salmonella strains by resulting in one 800-bp band in the sample tubes. The specificity of the PCR was assessed using 20 non-Salmonella strains...

  12. Fructose-asparagine is a primary nutrient during growth of Salmonella in the inflamed intestine.

    Directory of Open Access Journals (Sweden)

    Mohamed M Ali

    2014-06-01

    Full Text Available Salmonella enterica serovar Typhimurium (Salmonella is one of the most significant food-borne pathogens affecting both humans and agriculture. We have determined that Salmonella encodes an uptake and utilization pathway specific for a novel nutrient, fructose-asparagine (F-Asn, which is essential for Salmonella fitness in the inflamed intestine (modeled using germ-free, streptomycin-treated, ex-germ-free with human microbiota, and IL10-/- mice. The locus encoding F-Asn utilization, fra, provides an advantage only if Salmonella can initiate inflammation and use tetrathionate as a terminal electron acceptor for anaerobic respiration (the fra phenotype is lost in Salmonella SPI1- SPI2- or ttrA mutants, respectively. The severe fitness defect of a Salmonella fra mutant suggests that F-Asn is the primary nutrient utilized by Salmonella in the inflamed intestine and that this system provides a valuable target for novel therapies.

  13. Evaluation of the protective efficacy of Salmonella Gallinarum 9R ...

    African Journals Online (AJOL)

    Evaluation of the protective efficacy of Salmonella Gallinarum 9R strain vaccine against Salmonella strains isolated from cases suspected of salmonellosis outbreaks in poultry farms in central Ethiopia.

  14. Development of Rapid Detection and Genetic Characterization of Salmonella in Poultry Breeder Feeds

    Science.gov (United States)

    Jarquin, Robin; Hanning, Irene; Ahn, Soohyoun; Ricke, Steven C.

    2009-01-01

    Salmonella is a leading cause of foodborne illness in the United States, with poultry and poultry products being a primary source of infection to humans. Poultry may carry some Salmonella serovars without any signs or symptoms of disease and without causing any adverse effects to the health of the bird. Salmonella may be introduced to a flock by multiple environmental sources, but poultry feed is suspected to be a leading source. Detecting Salmonella in feed can be challenging because low levels of the bacteria may not be recovered using traditional culturing techniques. Numerous detection methodologies have been examined over the years for quantifying Salmonella in feeds and many have proven to be effective for Salmonella isolation and detection in a variety of feeds. However, given the potential need for increased detection sensitivity, molecular detection technologies may the best candidate for developing rapid sensitive methods for identifying small numbers of Salmonella in the background of large volumes of feed. Several studies have been done using polymerase chain reaction (PCR) assays and commercial kits to detect Salmonella spp. in a wide variety of feed sources. In addition, DNA array technology has recently been utilized to track the dissemination of a specific Salmonella serotype in feed mills. This review will discuss the processing of feeds and potential points in the process that may introduce Salmonella contamination to the feed. Detection methods currently used and the need for advances in these methods also will be discussed. Finally, implementation of rapid detection for optimizing control methods to prevent and remove any Salmonella contamination of feeds will be considered. PMID:22346699

  15. Development of Rapid Detection and Genetic Characterization of Salmonella in Poultry Breeder Feeds

    Directory of Open Access Journals (Sweden)

    Steven C. Ricke

    2009-07-01

    Full Text Available Salmonella is a leading cause of foodborne illness in the United States, with poultry and poultry products being a primary source of infection to humans. Poultry may carry some Salmonella serovars without any signs or symptoms of disease and without causing any adverse effects to the health of the bird. Salmonella may be introduced to a flock by multiple environmental sources, but poultry feed is suspected to be a leading source. Detecting Salmonella in feed can be challenging because low levels of the bacteria may not be recovered using traditional culturing techniques. Numerous detection methodologies have been examined over the years for quantifying Salmonella in feeds and many have proven to be effective for Salmonella isolation and detection in a variety of feeds. However, given the potential need for increased detection sensitivity, molecular detection technologies may the best candidate for developing rapid sensitive methods for identifying small numbers of Salmonella in the background of large volumes of feed. Several studies have been done using polymerase chain reaction (PCR assays and commercial kits to detect Salmonella spp. in a wide variety of feed sources. In addition, DNA array technology has recently been utilized to track the dissemination of a specific Salmonella serotype in feed mills. This review will discuss the processing of feeds and potential points in the process that may introduce Salmonella contamination to the feed. Detection methods currently used and the need for advances in these methods also will be discussed. Finally, implementation of rapid detection for optimizing control methods to prevent and remove any Salmonella contamination of feeds will be considered.

  16. Survival of Salmonella spp. In Waste Egg Wash Water

    Science.gov (United States)

    The survival of salmonellae under various environmental conditions has been subject of numerous research studies. Due to low densities of these organisms in natural samples, laboratory or clinical cultures were used to ensure that the initial density of salmonellae was sufficien...

  17. Effects of subtherapeutic concentrations of antimicrobials on gene acquisition events in Yersinia, Proteus, Shigella, and Salmonella recipient organisms in isolated ligated intestinal loops of swine.

    Science.gov (United States)

    Brewer, Matt T; Xiong, Nalee; Anderson, Kristi L; Carlson, Steve A

    2013-08-01

    To assess antimicrobial resistance and transfer of virulence genes facilitated by subtherapeutic concentrations of antimicrobials in swine intestines. 20 anesthetized pigs experimentally inoculated with donor and recipient bacteria. 4 recipient pathogenic bacteria (Salmonella enterica serotype Typhimurium, Yersinia enterocolitica, Shigella flexneri, or Proteus mirabilis) were incubated with donor bacteria in the presence of subinhibitory concentrations of 1 of 16 antimicrobials in isolated ligated intestinal loops in swine. Donor Escherichia coli contained transferrable antimicrobial resistance or virulence genes. After coincubations, intestinal contents were removed and assessed for pathogens that acquired new antimicrobial resistance or virulence genes following exposure to the subtherapeutic concentrations of antimicrobials. 3 antimicrobials (apramycin, lincomycin, and neomycin) enhanced transfer of an antimicrobial resistance plasmid from commensal E coli organisms to Yersinia and Proteus organisms, whereas 7 antimicrobials (florfenicol, hygromycin, penicillin G, roxarsone, sulfamethazine, tetracycline, and tylosin) exacerbated transfer of an integron (Salmonella genomic island 1) from Salmonella organisms to Yersinia organisms. Sulfamethazine induced the transfer of Salmonella pathogenicity island 1 from pathogenic to nonpathogenic Salmonella organisms. Six antimicrobials (bacitracin, carbadox, erythromycin, sulfathiazole, tiamulin, and virginiamycin) did not mediate any transfer events. Sulfamethazine was the only antimicrobial implicated in 2 types of transfer events. 10 of 16 antimicrobials at subinhibitory or subtherapeutic concentrations augmented specific antimicrobial resistance or transfer of virulence genes into pathogenic bacteria in isolated intestinal loops in swine. Use of subtherapeutic antimicrobials in animal feed may be associated with unwanted collateral effects.

  18. A Rare Case of Salmonella typhi Meningitis in an Eleven Month Old ...

    African Journals Online (AJOL)

    Non-typhoidal Salmonella are infrequent causes of childhood meningitis. Most reports of Salmonella typhi meningeal infections are confined to neonates. A rare instance of S. typhi in an otherwise healthy eleven month old infant is being reported. Keywords: Salmonella typhi, meningitis, infant.

  19. Persistent Salmonella enterica serovar Typhimurium Infection Increases the Susceptibility of Mice to Develop Intestinal Inflammation

    Directory of Open Access Journals (Sweden)

    Bárbara M. Schultz

    2018-05-01

    Full Text Available Chronic intestinal inflammations are triggered by genetic and environmental components. However, it remains unclear how specific changes in the microbiota, host immunity, or pathogen exposure could promote the onset and exacerbation of these diseases. Here, we evaluated whether Salmonella enterica serovar Typhimurium (S. Typhimurium infection increases the susceptibility to develop intestinal inflammation in mice. Two mouse models were used to evaluate the impact of S. Typhimurium infection: the chemical induction of colitis by dextran sulfate sodium (DSS and interleukin (IL-10−/− mice, which develop spontaneous intestinal inflammation. We observed that S. Typhimurium infection makes DSS-treated and IL-10−/− mice more susceptible to develop intestinal inflammation. Importantly, this increased susceptibility is associated to the ability of S. Typhimurium to persist in liver and spleen of infected mice, which depends on the virulence proteins secreted by Salmonella Pathogenicity Island 2-encoded type three secretion system (TTSS-2. Although immunization with a live attenuated vaccine resulted in a moderate reduction of the IL-10−/− mice susceptibility to develop intestinal inflammation due to previous S. Typhimurium infection, it did not prevent bacterial persistence. Our results suggest that persistent S. Typhimurium infection may increase the susceptibility of mice to develop inflammation in the intestine, which could be associated with virulence proteins secreted by TTSS-2.

  20. Using molecular techniques for rapid detection of Salmonella ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-02-01

    Feb 1, 2010 ... A total of 152 samples of chicken and chicken products ... detection of Salmonella species in the collected field samples ... that 16 million new cases of typhoid fever occur each ... vative methods for the rapid identification of Salmonella ... saved for the PCR-Non Selective test (PCR-NS) and 1 ml of the.

  1. Identification and characterization of salmonella serotypes using DNA spectral characteristics by fourier transform infrared (FT-IR) spectroscopy

    Science.gov (United States)

    Analysis of DNA samples of Salmonella serotypes (Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky) were performed using Fourier transform infrared spectroscopy (FT-IR) spectrometer by placing directly in contact with a diamond attenua...

  2. DNA sequence analysis of plasmids from multidrug resistant Salmonella enterica serotype Heidelberg isolates.

    Directory of Open Access Journals (Sweden)

    Jing Han

    Full Text Available Salmonella enterica serovar Heidelberg is among the most detected serovars in swine and poultry, ranks among the top five serotypes associated with human salmonellosis and is disproportionately associated with invasive infections and mortality in humans. Salmonella are known to carry plasmids associated with antimicrobial resistance and virulence. To identify plasmid-associated genes in multidrug resistant S. enterica serovar Heidelberg, antimicrobial resistance plasmids from five isolates were sequenced using the 454 LifeSciences pyrosequencing technology. Four of the isolates contained incompatibility group (Inc A/C multidrug resistance plasmids harboring at least eight antimicrobial resistance genes. Each of these strains also carried a second resistance plasmid including two IncFIB, an IncHI2 and a plasmid lacking an identified Inc group. The fifth isolate contained an IncI1 plasmid, encoding resistance to gentamicin, streptomycin and sulfonamides. Some of the IncA/C plasmids lacked the full concert of transfer genes and yet were able to be conjugally transferred, likely due to the transfer genes carried on the companion plasmids in the strains. Several non-IncA/C resistance plasmids also carried putative virulence genes. When the sequences were compared to previously sequenced plasmids, it was found that while all plasmids demonstrated some similarity to other plasmids, they were unique, often due to differences in mobile genetic elements in the plasmids. Our study suggests that Salmonella Heidelberg isolates harbor plasmids that co-select for antimicrobial resistance and virulence, along with genes that can mediate the transfer of plasmids within and among other bacterial isolates. Prevalence of such plasmids can complicate efforts to control the spread of S. enterica serovar Heidelberg in food animal and human populations.

  3. Survival of Salmonella in bathrooms and toilets in domestic homes following salmonellosis.

    Science.gov (United States)

    Barker, J; Bloomfield, S F

    2000-07-01

    The survival and environmental spread of Salmonella bacteria from domestic toilets was examined in homes, where a family member had recently suffered an attack of salmonellosis. In four out of six households tested, Salmonella bacteria persisted in the biofilm material found under the recess of the toilet bowl rim which was difficult to remove with household toilet cleaners. In two homes Salmonella bacteria became incorporated into the scaly biofilm adhering to the toilet bowl surface below the water line. Salmonella enteritidis persisted in one toilet for 4 weeks after the diarrhoea had stopped, despite the use of cleaning fluids. Salmonellas were not isolated from normally dry areas such as, the toilet seat, the flush handle and door handle. Toilet seeding experiments were set up with Salmonella enteritidis PT4 to mimic environmental conditions associated with acute diarrhoea. Flushing the toilet resulted in contamination of the toilet seat and the toilet seat lid. In one out of three seedings, Salmonella bacteria were also isolated from an air sample taken immediately after flushing, indicating that airborne spread of the organism could contaminate surfaces in the bathroom. In the seeded toilet Salmonella bacteria were isolated from the biofilm in the toilet bowl below the waterline for up to 50 d after seeding, and also on one occasion from the bowl water. The results suggest that during diarrhoeal illness, there is considerable risk of spread of Salmonella infection to other family members via the environment, including contaminated hands and surfaces in the toilet area.

  4. Multilocus Sequence Typing of the Clinical Isolates of Salmonella Enterica Serovar Typhimurium in Tehran Hospitals

    Directory of Open Access Journals (Sweden)

    Reza Ranjbar

    2017-09-01

    Full Text Available Background: Salmonella enterica serovar Typhimurium is one of the most important serovars of Salmonella enterica and is associated with human salmonellosis worldwide. Many epidemiological studies have focused on the characteristics of Salmonella Typhimurium in many countries as well as in Asia. This study was conducted to investigate the genetic characteristics of Salmonella Typhimurium using multilocus sequence typing (MLST. Methods: Clinical samples (urine, blood, and stool were collected from patients, who were admitted to 2 hospitals in Tehran between April and September, 2015. Salmonella Typhimurium strains were identified by conventional standard biochemical and serological testing. The antibiotic susceptibility patterns of the Salmonella Typhimurium isolates against 16 antibiotics was determined using the disk diffusion assay. The clonal relationship between the strains of Salmonella Typhimurium was analyzed using MLST. Results: Among the 68 Salmonella isolates, 31% (n=21 were Salmonella Typhimurium. Of the total 21 Salmonella Typhimurium isolates, 76% (n=16 were multidrug-resistant and showed resistance to 3 or more antibiotic families. The Salmonella Typhimurium isolates were assigned to 2 sequence types: ST19 and ST328. ST19 was more common (86%. Both sequence types were further assigned to 1 eBURST group. Conclusion: This is the first study of its kind in Iran to determine the sequence types of the clinical isolates of Salmonella Typhimurium in Tehran hospitals using MLST. ST19 was detected as the major sequence type of Salmonella Typhimurium.

  5. Estrogen-Related Receptor Alpha Confers Methotrexate Resistance via Attenuation of Reactive Oxygen Species Production and P53 Mediated Apoptosis in Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Peng Chen

    2014-01-01

    Full Text Available Osteosarcoma (OS is a malignant tumor mainly occurring in children and adolescents. Methotrexate (MTX, a chemotherapy agent, is widely used in treating OS. However, treatment failures are common due to acquired chemoresistance, for which the underlying molecular mechanisms are still unclear. In this study, we report that overexpression of estrogen-related receptor alpha (ERRα, an orphan nuclear receptor, promoted cell survival and blocked MTX-induced cell death in U2OS cells. We showed that MTX induced ROS production in MTX-sensitive U2OS cells while ERRα effectively blocked the ROS production and ROS associated cell apoptosis. Our further studies demonstrated that ERRα suppressed ROS induction of tumor suppressor P53 and its target genes NOXA and XAF1 which are mediators of P53-dependent apoptosis. In conclusion, this study demonstrated that ERRα plays an important role in the development of MTX resistance through blocking MTX-induced ROS production and attenuating the activation of p53 mediated apoptosis signaling pathway, and points to ERRα as a novel target for improving osteosarcoma therapy.

  6. A rabbit model of non-typhoidal Salmonella bacteremia.

    Science.gov (United States)

    Panda, Aruna; Tatarov, Ivan; Masek, Billie Jo; Hardick, Justin; Crusan, Annabelle; Wakefield, Teresa; Carroll, Karen; Yang, Samuel; Hsieh, Yu-Hsiang; Lipsky, Michael M; McLeod, Charles G; Levine, Myron M; Rothman, Richard E; Gaydos, Charlotte A; DeTolla, Louis J

    2014-09-01

    Bacteremia is an important cause of morbidity and mortality in humans. In this study, we focused on the development of an animal model of bacteremia induced by non-typhoidal Salmonella. New Zealand White rabbits were inoculated with a human isolate of non-typhoidal Salmonella strain CVD J73 via the intra-peritoneal route. Blood samples were collected at specific time points and at euthanasia from infected rabbits. Additionally, tissue samples from the heart, lungs, spleen, gastrointestinal tract, liver and kidneys were obtained at euthanasia. All experimentally infected rabbits displayed clinical signs of disease (fever, dehydration, weight loss and lethargy). Tissues collected at necropsy from the animals exhibited histopathological changes indicative of bacteremia. Non-typhoidal Salmonella bacteria were detected in the blood and tissue samples of infected rabbits by microbiological culture and real-time PCR assays. The development of this animal model of bacteremia could prove to be a useful tool for studying how non-typhoidal Salmonella infections disseminate and spread in humans. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Prior DNA vaccination does not interfere with the live-attenuated measles vaccine.

    Science.gov (United States)

    Premenko-Lanier, Mary; Rota, Paul; Rhodes, Gary; Bellini, William; McChesney, Michael

    2004-01-26

    The currently used live-attenuated measles vaccine is very effective although maternal antibody prevents its administration prior to 6 months of age. We are investigating the ability of a DNA vaccine encoding the measles viral hemagglutinin, fusion and nucleoprotein to protect newborn infants from measles. Here, we show that a measles DNA vaccine protects juvenile macaques from pathogenic measles virus challenge and that macaques primed and boosted with this DNA vaccine have anemnestic antibody and cell-mediated responses after vaccination with a live-attenuated canine distemper-measles vaccine. Therefore, this DNA vaccine administered to newborn infants may not hinder the subsequent use of live-attenuated measles vaccine.

  8. Salmonella modulation of host cell gene expression promotes its intracellular growth.

    Directory of Open Access Journals (Sweden)

    Sebastian Hannemann

    Full Text Available Salmonella Typhimurium has evolved a complex functional interface with its host cell largely determined by two type III secretion systems (T3SS, which through the delivery of bacterial effector proteins modulate a variety of cellular processes. We show here that Salmonella Typhimurium infection of epithelial cells results in a profound transcriptional reprogramming that changes over time. This response is triggered by Salmonella T3SS effector proteins, which stimulate unique signal transduction pathways leading to STAT3 activation. We found that the Salmonella-stimulated changes in host cell gene expression are required for the formation of its specialized vesicular compartment that is permissive for its intracellular replication. This study uncovers a cell-autonomous process required for Salmonella pathogenesis potentially opening up new avenues for the development of anti-infective strategies that target relevant host pathways.

  9. Salmonella modulation of host cell gene expression promotes its intracellular growth.

    Science.gov (United States)

    Hannemann, Sebastian; Gao, Beile; Galán, Jorge E

    2013-01-01

    Salmonella Typhimurium has evolved a complex functional interface with its host cell largely determined by two type III secretion systems (T3SS), which through the delivery of bacterial effector proteins modulate a variety of cellular processes. We show here that Salmonella Typhimurium infection of epithelial cells results in a profound transcriptional reprogramming that changes over time. This response is triggered by Salmonella T3SS effector proteins, which stimulate unique signal transduction pathways leading to STAT3 activation. We found that the Salmonella-stimulated changes in host cell gene expression are required for the formation of its specialized vesicular compartment that is permissive for its intracellular replication. This study uncovers a cell-autonomous process required for Salmonella pathogenesis potentially opening up new avenues for the development of anti-infective strategies that target relevant host pathways.

  10. Salmonella Typhi sense host neuroendocrine stress hormones and release the toxin haemolysin E

    Science.gov (United States)

    Karavolos, Michail H; Bulmer, David M; Spencer, Hannah; Rampioni, Giordano; Schmalen, Ira; Baker, Stephen; Pickard, Derek; Gray, Joe; Fookes, Maria; Winzer, Klaus; Ivens, Alasdair; Dougan, Gordon; Williams, Paul; Khan, C M Anjam

    2011-01-01

    Salmonella enterica serovar Typhi (S. typhi) causes typhoid fever. We show that exposure of S. typhi to neuroendocrine stress hormones results in haemolysis, which is associated with the release of haemolysin E in membrane vesicles. This effect is attributed to increased expression of the small RNA micA and RNA chaperone Hfq, with concomitant downregulation of outer membrane protein A. Deletion of micA or the two-component signal-transduction system, CpxAR, abolishes the phenotype. The hormone response is inhibited by the β-blocker propranolol. We provide mechanistic insights into the basis of neuroendocrine hormone-mediated haemolysis by S. typhi, increasing our understanding of inter-kingdom signalling. PMID:21331094

  11. [Use of bacteriphages against Salmonella Enteritidis: a prevention tool].

    Science.gov (United States)

    García, Cristina; Marín, Clara; Catalá-Gregori, Pablo; Soriano, Jose Miguel

    2015-06-01

    Salmonellosis is a highly prevalent disease still searching for preventive tools to avoid contamination level priority public health. The in vitro effect of bacteriophages against Salmonella enteritidis was evaluated as a prevention tool. Two tests with three concentrations of bacteriophages were conducted against two strains of Salmonella Enteritidis inoculated in fresh faeces of laying hens. Each test had a positive control. Thus, four groups in each test were evaluated. Each experimental group included two replicates, and three plates were incubated per replicate. The concentrations tested were three: commercial solution (5 × 10(7) pfu/mL), and two dilutions (1/10 and 1/30). One of the strains tested was CECT 4300, a certified strain of Colección Española de Cultivo Tipo and the other a field isolated strain in a sacrificed hen farm. Both strains were inoculated at 1.3 × 10(5) cfu/g of faeces in each of the four groups. Isolation and identification of bacteria by ISO6579 was done at various times after inoculation: 1 minute, 24 hours and 7 days. In the first test, with certified strain, Salmonella was isolated in all groups at time 1 minute. After 24 hours, Salmonella was isolated in all groups except in one of the replicas treated with 1/10 dilution of bacteriophages, one of the other replica plate treated with 1/10 dilution, and two plates of the two replicas treated with the commercial solution. After 7 days, the bacteria were not isolated from any of the experimental groups. In the second test, with the field strain, Salmonella was isolated in all groups at time 1 minute. After 24 hours, Salmonella was isolated in all groups except in one of the replicas treated with 1/10 dilution of bacteriophages and the two replicas treated with the commercial solution. Salmonella was not isolated in any of the experimental groups at 7 days. The use of bacteriophages reduced Salmonella enteritidis isolates in faeces at 24 hours after the application, so it could be

  12. Prevalence and molecular profiles of Salmonella collected at a commercial turkey processing plant.

    Science.gov (United States)

    Nde, Chantal W; Sherwood, Julie S; Doetkott, Curt; Logue, Catherine M

    2006-08-01

    In this study, whole carcasses were sampled at eight stages on a turkey-processing line and Salmonella prevalence was determined using enrichment techniques. Recovered Salmonella was further characterized using serotyping and the molecular profiles were determined using pulsed-field gel electrophoresis (PFGE). Prevalence data showed that contamination rates varied along the line and were greatest after defeathering and after chilling. Analysis of contamination in relation to serotypes and PFGE profiles found that on some visits the same serotype was present all along the processing line while on other days, additional serotypes were recovered that were not detected earlier on the line, suggesting that the birds harbored more than one serotype of Salmonella or there was cross-contamination occurring during processing. Overall, this study found fluctuations in Salmonella prevalence along a turkey-processing line. Following washing, Salmonella prevalence was significantly reduced, suggesting that washing is critical for Salmonella control in turkey processing and has significant application for controlling Salmonella at the postdefeathering and prechill stages where prevalence increased.

  13. Identification of metabolic pathways essential for fitness of Salmonella Typhimurium in vivo.

    Directory of Open Access Journals (Sweden)

    Lotte Jelsbak

    Full Text Available Bacterial infections remain a threat to human and animal health worldwide, and there is an urgent need to find novel targets for intervention. In the current study we used a computer model of the metabolic network of Salmonella enterica serovar Typhimurium and identified pairs of reactions (cut sets predicted to be required for growth in vivo. We termed such cut sets synthetic auxotrophic pairs. We tested whether these would reveal possible combined targets for new antibiotics by analyzing the performance of selected single and double mutants in systemic mouse infections. One hundred and two cut sets were identified. Sixty-three of these included only pathways encoded by fully annotated genes, and from this sub-set we selected five cut sets involved in amino acid or polyamine biosynthesis. One cut set (asnA/asnB demonstrated redundancy in vitro and in vivo and showed that asparagine is essential for S. Typhimurium during infection. trpB/trpA as well as single mutants were attenuated for growth in vitro, while only the double mutant was a cut set in vivo, underlining previous observations that tryptophan is essential for successful outcome of infection. speB/speF,speC was not affected in vitro but was attenuated during infection showing that polyamines are essential for virulence apparently in a growth independent manner. The serA/glyA cut-set was found to be growth attenuated as predicted by the model. However, not only the double mutant, but also the glyA mutant, were found to be attenuated for virulence. This adds glycine production or conversion of glycine to THF to the list of essential reactions during infection. One pair (thrC/kbl showed true redundancy in vitro but not in vivo demonstrating that threonine is available to the bacterium during infection. These data add to the existing knowledge of available nutrients in the intra-host environment, and have identified possible new targets for antibiotics.

  14. Effect of Carvacrol on Salmonella Saintpaul Biofilms on Stainless ...

    African Journals Online (AJOL)

    Purpose: To evaluate the effect of carvacrol against Salmonella Saintpaul biofilms on stainless steel surface. Methods: The effects of carvacrol on planktonic cells were evaluated by determining the minimum inhibitory concentration and minimal bactericidal concentration. The action of carvacrol on Salmonella Saintpaul ...

  15. Prevalence of Salmonella spp. in reptiles

    OpenAIRE

    加藤, 行男; 村上, 賢

    2007-01-01

    A total of 291 fecal samples from 252 wild reptiles and 39 pet reptiles were examined for the prevalence of Salmonella spp. in Japan. Salmonella spp. were isolated from 29 (11.5%) of 252 wild reptiles and 22 (55.6%) of 39 pet reptiles. The isolates were identified into subspecies I to IV. The majority of isolates (43.6%) belonged to subspecies I and these isolates could be identified into 9 serovars. The serovars isolated were found to be S. Newport, S. Litchifield and S. Thompson which cause...

  16. Salmonella-infektion kompliceret med akut nyreinsufficiens

    DEFF Research Database (Denmark)

    Thøgersen, Thøger; Jensen, Jørgen Erik; Jespersen, Bente

    2003-01-01

    Acute renal failure is a known complication to Salmonella gastroenteritis, and patients with chronic renal failure or impaired host defence are at increased risk. In the two presented cases there had been a few days of gastroenteritis before the hospitalisation, but the only symptoms...... at the admission were fatigue and dyspnoea. In both cases severe uraemia had developed and the patients and their physicians did not expect the episode of gastroenteritis to be the only etiology of acute renal failure. Both patients had normal renal histology and Salmonella was grown in their faeces. Subsequently...

  17. Prevalence and antimicrobial resistance pattern of Salmonella in animal feed produced in Namibia.

    Science.gov (United States)

    Shilangale, Renatus P; Di Giannatale, Elisabetta; Chimwamurombe, Percy M; Kaaya, Godwin P

    2012-01-01

    The occurrence of Salmonella is a global challenge in the public health and food production sectors. Our study investigated the prevalence, serovar and antimicrobial susceptibility of strains of Salmonella serovars isolated from animal feed (meat-and-bone and blood meal) samples from two commercial abattoirs in Namibia. A total of 650 samples (n=650) were examined for the presence of Salmonella. Results showed that 10.9% (n=71) were positive for Salmonella. Of the Salmonella serovars isolated, S. Chester was the most commonly isolated serovar (19.7%), followed by S. Schwarzengrund at 12.7%. From the Salmonella isolates, 19.7% (n=14) were resistant to one or more of the antimicrobials (nalidixic acid, trimethoprim-sulfamethoxazole, sulfisoxazole, streptomycin and/or tetracycline), whereas 80.3% (n=57) were susceptible to all 16 antimicrobials tested. Resistance to sulfisoxazole and the trimethroprimsuflamethoxazole combination were the most common. The resistant isolates belonged to ten different Salmonella serovars. The susceptibility of most of the Salmonella isolated to the antimicrobials tested indicates that anti-microbial resistance is not as common and extensive in Namibia as has been reported in many other countries. It also appears that there is a range of antimicrobials available that are effective in managing Salmonella infections in Namibia. However, there is some evidence that resistance is developing and this will need further monitoring to ensure it does not become a problem.

  18. Obacunone Represses Salmonella Pathogenicity Islands 1 and 2 in an envZ-Dependent Fashion

    Science.gov (United States)

    Vikram, Amit; Jayaprakasha, Guddadarangavvanahally K.; Jesudhasan, Palmy R.

    2012-01-01

    Obacunone belongs to a class of unique triterpenoids called limonoids, present in Citrus species. Previous studies from our laboratory suggested that obacunone possesses antivirulence activity and demonstrates inhibition of cell-cell signaling in Vibrio harveyi and Escherichia coli O157:H7. The present work sought to determine the effect of obacunone on the food-borne pathogen Salmonella enterica serovar Typhimurium LT2 by using a cDNA microarray. Transcriptomic studies indicated that obacunone represses Salmonella pathogenicity island 1 (SPI1), the maltose transporter, and the hydrogenase operon. Furthermore, phenotypic data for the Caco-2 infection assay and maltose utilization were in agreement with microarray data suggesting repression of SPI1 and maltose transport. Further studies demonstrated that repression of SPI1 was plausibly mediated through hilA. Additionally, obacunone seems to repress SPI2 under SPI2-inducing conditions as well as in Caco-2 infection models. Furthermore, obacunone seems to repress hilA in an EnvZ-dependent fashion. Altogether, the results of the study seems to suggest that obacunone exerts an antivirulence effect on S. Typhimurium and may serve as a lead compound for development of antivirulence strategies for S. Typhimurium. PMID:22843534

  19. Inactivation of Salmonella spp. on tomatoes by plant molecules.

    Science.gov (United States)

    Mattson, Tyler E; Johny, Anup Kollanoor; Amalaradjou, Mary Anne Roshni; More, Karen; Schreiber, David T; Patel, Jitu; Venkitanarayanan, Kumar

    2011-01-05

    The efficacy of carvacrol (CAR), trans-cinnamaldehyde (TC), eugenol (EUG) and β-resorcylic acid (BR) as a wash treatment for reducing Salmonella spp. on tomatoes was investigated. Plum tomatoes inoculated with a six-serotype mixture of Salmonella (10⁸CFU) were subjected to washing in sterile deionized water (control) or deionized water containing chlorine (100 ppm), CAR (0.25 and 0.75%), TC (0.5 and 0.75%), EUG (0.25 and 0.75%), or BR (0.75 and 1.0%) for 15 sec, 1 min, and 3 min. The plant molecules were more effective (Pwashing in water and chlorine. Both concentrations of CAR and TC, and 0.75% EUG decreased Salmonella counts on tomatoes by~6.0 log CFU/ml at 1 min. Both concentrations of BR decreased the pathogen on tomatoes to undetectable levels at 3 min of exposure. Washing of tomatoes in deionized water and chlorine for 3 min reduced Salmonella by ca. 2.0 and 4.0 log CFU/ml, respectively. No Salmonella was detected in the wash water containing the plant molecules or chlorine, whereas a substantial population of the pathogen survived in the control wash water. Moreover, none of the dipping treatments had any effect on the red color of tomatoes (P>0.05). Results indicate that CAR, TC, EUG and BR could effectively be used to kill Salmonella on tomatoes, but additional studies on sensory and quality characteristics of tomatoes treated with plant molecules are warranted. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Survey of co-infection by Salmonella and oxyurids in tortoises

    Directory of Open Access Journals (Sweden)

    Dipineto Ludovico

    2012-05-01

    Full Text Available Abstract Background Salmonella spp. and oxyurids are among the most prevalent bacterial and parasitic agents in reptiles. These organisms are routinely isolated in healthy tortoises, although heavy infections may cause significant pathology. Tortoises are considered a common source of reptile-associated salmonellosis, an important zoonosis reported worldwide. A survey of the prevalence of Salmonella spp. and oxyurids in 53 tortoises was conducted in southern Italy and a possible correlation between the two pathogens was therefore investigated. Results Salmonella spp. and oxyurids were detected with a prevalence of 49.1 and 81.1%, respectively. A significant positive correlation between Salmonella spp. and oxyurids was demonstrated. However, confounding factors related to husbandry could have been involved in determining this correlation. Conclusions Our results suggest that caution should be exercised in translocation, husbandry, and human contact with tortoises and other exotic pets. Further studies on the epidemiology, molecular characterization and pathogenesis of Salmonella and oxyurids are needed to assess the actual impact of these organisms, as single or associated infections, on tortoises and on other exotic pets.

  1. Camel as a transboundary vector for emerging exotic Salmonella serovars.

    Science.gov (United States)

    Ghoneim, Nahed H; Abdel-Moein, Khaled A; Zaher, Hala

    2017-05-01

    The current study was conducted to shed light on the role of imported camels as a transboundary vector for emerging exotic Salmonella serovars. Fecal samples were collected from 206 camels directly after slaughtering including 25 local camels and 181 imported ones as well as stool specimens were obtained from 50 slaughterhouse workers at the same abattoir. The obtained samples were cultured while Salmonella serovars were identified through Gram's stain films, biochemical tests and serotyping with antisera kit. Moreover, the obtained Salmonella serovars were examined by PCR for the presence of invA and stn genes. The overall prevalence of Salmonella serovars among the examined camels was 8.3%. Stn gene was detected in the vast majority of exotic strains (11/14) 78.6% including emerging serovars such as Salmonella Saintpaul, S. Chester, S. Typhimurium whereas only one isolate from local camels carried stn gene (1/3) 33.3%. On the other hand, none of the examined humans yielded positive result. Our findings highlight the potential role of imported camels as a transboundary vector for exotic emerging Salomenella serovars.

  2. Modification Of Carry-Blair Transport Media For Storage Salmonella typhi

    Directory of Open Access Journals (Sweden)

    Yati Supriatin

    2016-09-01

    Full Text Available The aim of this study was to determine transport media modification as alternative media to replace Carry Blair. One type of transport media that often use to carry faeces specimens suspected to contain Salmonella typhi is Carry-Blair media. Studies have been conducted experimentally by storing Salmonella typhi on alternative transport media with Peptone composition, disodium Phosphate, Sodium chloride, Calcium chloride, which is made using a semi-solid and Carry-Blair as a control. Three variety of storage was done (0 hour,6 hours,9 hours at a temperature 4⁰-8⁰C and then Salmonella typhi was inoculated in Salmonella Shigella Agar using spread plate technique incubated during 24 hours at 37⁰C, counted the number of colonies by the plate count method using the colony counter. The results of ANOVA could be concluded that modification media could be use as alternative media replace Carry-Blair at 6 hours. Based on regression correlation test was assumed that the Salmonella typhi bacteria still life at less than 11 hours 54 minutes.

  3. Salmonella typhi

    OpenAIRE

    Mochammad, Hatta

    2008-01-01

    This manuscript could use as research on infectious diseases Multi-locus variable-number tandem repeat analysis differentiated 297 Salmonella enterica serovar Typhi blood culture isolates from Makassar in 76 genotypes and a single unique S. Typhi genotype was isolated from the cholecystectomy specimens of four patients with cholelithiasis. The high diversity in S. Typhi genotypes circulating in Makassar indicates that the number of carriers could be very large, which may complicat...

  4. Salmonella enterica induces and subverts the plant immune system

    KAUST Repository

    Garcí a, Ana V.; Hirt, Heribert

    2014-01-01

    ). Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS) as T3SS

  5. Mechanisms of HO-1 mediated attenuation of renal immune injury: a gene profiling study.

    Science.gov (United States)

    Duann, Pu; Lianos, Elias A

    2011-10-01

    Using a mouse model of immune injury directed against the renal glomerular vasculature and resembling human forms of glomerulonephritis (GN), we assessed the effect of targeted expression of the cytoprotective enzyme heme oxygenase (HO)-1. A human (h) HO-1 complementary DNAN (cDNA) sequence was targeted to glomerular epithelial cells (GECs) using a GEC-specific murine nephrin promoter. Injury by administration of antibody against the glomerular basement membrane (anti-GBM) to transgenic (TG) mice with GEC-targeted hHO-1 was attenuated compared with wild-type (WT) controls. To explore changes in the expression of genes that could mediate this salutary effect, we performed gene expression profiling using a microarray analysis of RNA isolated from the renal cortex of WT or TG mice with or without anti-GBM antibody-induced injury. Significant increases in expression were detected in 9 major histocompatibility complex (MHC)-class II genes, 2 interferon-γ (IFN-γ)-inducible guanosine triphosphate (GTP)ases, and 3 genes of the ubiquitin-proteasome system. The increase in MHC-class II and proteasome gene expression in TG mice with injury was validated by real-time polymerase chain reaction (PCR) or Western blot analysis. The observations point to novel mechanisms underlying the cytoprotective effect of HO-1 in renal immune injury. Copyright © 2011. Published by Mosby, Inc.

  6. Expression of chicken LEAP-2 in the reproductive organs and embryos and in response to Salmonella enterica infection.

    Science.gov (United States)

    Michailidis, Georgios

    2010-06-01

    In recent years host antimicrobial peptides and proteins have been recognised as key mediators of the innate immune response in many vertebrate species, providing the first line of defense against potential pathogens. In chickens a number of cationic antimicrobial peptides have been recently identified. However, although these peptides have been studied extensively in the avian gastrointestinal tract, little is known about their function in the chicken reproductive organs and embryos. Chicken Liver Expressed Antimicrobial Peptide-2 (cLEAP-2) has been previously reported to function in protecting birds against microbial attack. The aim of this study was to investigate the expression of cLEAP-2 gene in the chicken reproductive organs, as well as in chicken embryos during embryonic development, and to determine whether cLEAP-2 expression in the chicken reproductive organs was constitutive or induced as a response to Salmonella enteritidis infection. RNA was extracted from ovary, oviduct, testis and epididymis of sexually mature healthy and Salmonella infected birds, as well as from chicken embryos until day ten of embryonic development. Expression analysis data revealed that cLEAP-2 was expressed in the chicken ovary, testis and epididymis as well as in embryos during early embryonic development. Quantitative real-time PCR analysis revealed that cLEAP-2 expression was constitutive in the chicken epididymis, but was significantly up regulated in the chicken gonads, following Salmonella infection. In addition, expression of cLEAP-2 during chicken embryogenesis appeared to be developmentally regulated. These data provide evidence to suggest a key role of cLEAP-2 in the protection of the chicken reproductive organs and the developing embryos from Salmonella colonization.

  7. Salmonella enteridis Septic Arthritis: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Esat Uygur

    2013-01-01

    Full Text Available Introduction. Nontyphoidal salmonellosis causes significant morbidity, is transmitted via fecal-oral route, and is a worldwide cause of gastroenteritis, bacteremia, and local infections. Salmonella is a less common etiologic factor for septic arthritis compared with other gram-negative bacteria. Cases. We present two septic arthritis cases with Salmonella enteridis as a confirmed pathogen and also discuss the predisposing factors and treatment. Discussion. Septic arthritis is an orthopedic emergency. The gold standard treatment of septic arthritis is joint debridement, antibiotic therapy according to the culture results, and physiotherapy, which should start in the early postoperative period to prevent limitation of motion. Salmonella is an atypical agent for septic arthritis. It must be particularly kept in mind as an etiologic factor for the acute arthritis of a patient with sickle cell anemia and systemic lupus erythematosus. Clinicians should be cautious that the white blood cell count in synovial fluid can be under 50.000/mm3 in immune compromised individuals with septic arthritis. The inflammatory response can be deficient, or the microorganism may be atypical. Conclusion. Atypical bacteria such as Salmonella species in immune compromised patients can cause joint infections. Therefore, Salmonella species must always be kept in mind for the differential diagnosis of septic arthritis in a clinically relevant setting.

  8. Structural and enzymatic characterization of a host-specificity determinant from Salmonella

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Amanda C. [Rockefeller University, New York, NY 10065 (United States); Spanò, Stefania; Galán, Jorge E. [Yale University School of Medicine, New Haven, CT 06536 (United States); Stebbins, C. Erec, E-mail: stebbins@rockefeller.edu [Rockefeller University, New York, NY 10065 (United States)

    2014-02-01

    The Salmonella effector protein GtgE functions as a cysteine protease to cleave a subset of the Rab-family GTPases and to prevent delivery of antimicrobial agents to the Salmonella-containing vacuole. GtgE is an effector protein from Salmonella Typhimurium that modulates trafficking of the Salmonella-containing vacuole. It exerts its function by cleaving the Rab-family GTPases Rab29, Rab32 and Rab38, thereby preventing the delivery of antimicrobial factors to the bacteria-containing vacuole. Here, the crystal structure of GtgE at 1.65 Å resolution is presented, and structure-based mutagenesis and in vivo infection assays are used to identify its catalytic triad. A panel of cysteine protease inhibitors were examined and it was determined that N-ethylmaleimide, antipain and chymostatin inhibit GtgE activity in vitro. These findings provide the basis for the development of novel therapeutic strategies to combat Salmonella infections.

  9. A questionnaire-based, retrospective field study of persistence of Salmonella Enteritidis and Salmonella Typhimurium in Danish broiler houses

    DEFF Research Database (Denmark)

    Gradel, K.O.; Rattenborg, Erik

    2003-01-01

    A questionnaire-based, retrospective field study was conducted in 78 Danish broiler houses (analytical units) on 42 farms. In spring 1997, all these broiler houses had been infected with Salmonella Enteritidis, phage type 8, and/or Salmonella Typhimurium, definitive-type 66, by day-old chicks del...... soap and water for washing hands in the anteroom, hygiene barriers when removing dead broilers, gravel alongside the broiler house, systematic checks of indoor rodent-bait depots, and combined surface and pulse-fogging disinfection....

  10. Número mais provável de Salmonella isoladas de carcaças de frango resfriadas Most probable number of Salmonella isolated from refrigerated broiler carcasses

    Directory of Open Access Journals (Sweden)

    Anderlise Borsoi

    2010-11-01

    Full Text Available A Salmonella permanece um importante problema na avicultura e, considerando os patógenos transmitidos por alimentos, aparece como um dos agentes principais em surtos de toxinfecções alimentares. Para auxiliar na avaliação de riscos em adquirir infecção alimentar via carne de frangos que sofreram cocção inadequada, ou através de contaminação cruzada a partir desses animais, torna-se importante determinar a extensão de contaminação por patógenos em carne crua. No presente trabalho, foram analisadas 180 carcaças de frangos resfriadas, adquiridas em varejos, para pesquisa de Salmonella com determinação do número de células da bactéria. Foi utilizado o método do número mais provável (NMP nos ágares para isolamento verde brilhante com novobiocina (BGN e xilose-lisina tergitol 4 (XLT4. Os resultados mostraram 12,2% de ocorrência de Salmonella nas carcaças de frangos resfriadas e a média de NMP de Salmonella por mL, na leitura pelo ágar XLT4 foi de 2,7 células e no ágar BGN foi de 1,3 células. Os sorovares de Salmonella isolados das carcaças de frangos no estudo foram S. Enteritidis, S. Agona, S.Rissen, S. Heidelberg e S. Livingstone. A análise dos resultados demonstrou existir um número variável de células de Salmonella contaminando as carcaças de frango resfriadas que estão à venda ao consumidor.Salmonella in poultry remains an important worldwide problem, and among foodborne pathogens, the Salmonella appears as one of the most important outbreaks agents. To assess the risks of acquiring infection via undercooked poultry or cross contamination from chickens, it is important to determine the extent of the contamination on raw poultry with this pathogen. In this study, 180 refrigerated broiler carcasses, obtained from local stores, were assessed to recover Salmonella by the most probable number (MPN method to quantify bacterias cells onto brilliant green agar with novobiocin (BGN and xylose lysin tergitol 4 agar

  11. Protocatechuic aldehyde attenuates cisplatin-induced acute kidney injury by suppressing Nox-mediated oxidative stress and renal inflammation

    Directory of Open Access Journals (Sweden)

    Li Gao

    2016-12-01

    Full Text Available Cisplatin is a classic chemotherapeutic agent widely used to treat different types of cancers including ovarian, head and neck, testicular and uterine cervical carcinomas. However, cisplatin induces acute kidney injury by directly triggering an excessive inflammatory response, oxidative stress and programmed cell death of renal tubular epithelial cells. All of which lead to higher mortality rates in patients. In this study we examined the protective effect of protocatechuic aldehyde (PA in vitro in cisplatin-treated tubular epithelial cells and in vivo in cisplatin nephropathy. PA is a monomer of Traditional Chinese Medicine isolated from the root of S. miltiorrhiza. Results show that PA prevented cisplatin-induced decline of renal function and histological damage, which was confirmed by attenuation of KIM1 in both mRNA and protein levels. Moreover, PA reduced renal inflammation by suppressing oxidative stress and programmed cell death in response to cisplatin, which was further evidenced by in vitro data. Of note, PA suppressed NAPDH oxidases, including Nox2 and Nox4, in a dosage-dependent manner. Moreover, silencing Nox4, but not Nox2, removed the inhibitory effect of PA on cisplatin-induced renal injury, indicating that Nox4 may play a pivotal role in mediating the protective effect of PA in cisplatin-induced acute kidney injury. Collectively, our data indicate that PA largely blocked cisplatin-induced acute kidney injury by suppressing Nox-mediated oxidative stress and renal inflammation without compromising anti-tumor activity of cisplatin. These findings suggest that PA and its derivatives may serve as potential protective agents for cancer patients with cisplatin treatment.

  12. Combination of Cymbopogon citratus and Allium cepa essential oils increased antibacterial activity in leafy vegetables.

    Science.gov (United States)

    Ortega-Ramirez, Luis A; Silva-Espinoza, Brenda A; Vargas-Arispuro, Irasema; Gonzalez-Aguilar, Gustavo A; Cruz-Valenzuela, M Reynaldo; Nazzaro, Filomena; Ayala-Zavala, J Fernando

    2017-05-01

    Cymbopogon citratus and Allium cepa essential oils (EOs) are rich in terpenes and sulfur compounds respectively, both with antibacterial activity and different cell targets, supporting the idea that their combination can increase their efficacy. Major constituents of C. citratus were geranial and neral, while A. cepa presented dipropyl disulfide and dipropyl trisulfide. Cymbopogon citratus and A. cepa EOs inhibited the in vitro growth of Escherichia coli O157:H7 (minimal inhibitory concentrations of 2.21 and 5.13 g L -1 respectively), Salmonella Choleraesuis (3.04 and 1.28 g L -1 ), Listeria monocytogenes (1.33 and 2.56 g L -1 ) and Staphylococcus aureus (0.44 and 5.26 g L -1 ). Application of the EO combination to spinach caused a greater reduction in E. coli (2.34 log colony-forming units (CFU) g -1 ), S. Choleraesuis (2.94 log CFU g -1 ), L. monocytogenes (2.06 log CFU g -1 ) and S. aureus (1.37 log CFU g -1 ) compared with higher doses of individual EOs; a similar effect was observed for romaine lettuce. Individual and combined EOs caused a reduction in flavor acceptability level; however, no significant differences were found among odor acceptability of control vegetables and those treated with the EO combination and C. citratus EO. Leafy vegetables treated with the EO combination showed higher antibacterial protection and odor acceptability compared with individual EO treatments. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  13. Assessing the prevalence of Salmonella enterica in poultry hatcheries by using hatched eggshell membranes.

    Science.gov (United States)

    Chao, M-R; Hsien, C-H; Yeh, C-M; Chou, S-J; Chu, C; Su, Y-C; Yu, C-Y

    2007-08-01

    Salmonella enterica causes a number of significant poultry diseases and is also a major pathogen in humans. Most poultry infected by Salmonella become carriers; infection may also be fatal, depending on the particular serovar and the age of the bird at infection. Younger birds are more susceptible to infection by Salmonella, so it is critical that hatcheries monitor birds. We developed a method to use hatched eggshell membranes (HEM) to assess contamination by Salmonella in poultry hatching cabinets and to evaluate the prevalence of Salmonella in a goose hatchery and rearing farm. Comparison of the Salmonella isolation rate in hatching cabinets using 3 sampling methods showed that the highest Salmonella contamination was detected in HEM, and that these results differed significantly from those obtained from fluff samples and cabinet swab samples (P chicken, and duck hatcheries. The lowest Salmonella-positive rate was found for the chicken hatchery, followed by the goose and the duck hatcheries (P hatcheries: A, B, C1, C2, D, and E. The distribution of these serogroups differed among the hatcheries. Salmonella serogroup C1 was the major serogroup found in geese, compared with serogroup B in chickens and ducks. However, Salmonella Typhimurium was dominant in 1 goose hatchery and also in geese from this hatchery that had been transferred to a farm. Antibiotic susceptibility analysis showed that Salmonella Typhimurium strains isolated from the farm geese with diarrhea showed significantly higher resistance to doxycycline, colistin, sulfamethoxazole-trimethoprin, and cephalothin than those isolated from the hatchery (P hatcheries and rearing farms.

  14. Activation of iNKT Cells Prevents Salmonella-Enterocolitis and Salmonella-Induced Reactive Arthritis by Downregulating IL-17-Producing γδT Cells

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    Mariángeles Noto Llana

    2017-09-01

    Full Text Available Reactive arthritis (ReA is an inflammatory condition of the joints that arises following an infection. Salmonella enterocolitis is one of the most common infections leading to ReA. Although the pathogenesis remains unclear, it is known that IL-17 plays a pivotal role in the development of ReA. IL-17-producers cells are mainly Th17, iNKT, and γδT lymphocytes. It is known that iNKT cells regulate the development of Th17 lineage. Whether iNKT cells also regulate γδT lymphocytes differentiation is unknown. We found that iNKT cells play a protective role in ReA. BALB/c Jα18−/− mice suffered a severe Salmonella enterocolitis, a 3.5-fold increase in IL-17 expression and aggravated inflammation of the synovial membrane. On the other hand, activation of iNKT cells with α-GalCer abrogated IL-17 response to Salmonella enterocolitis and prevented intestinal and joint tissue damage. Moreover, the anti-inflammatory effect of α-GalCer was related to a drop in the proportion of IL-17-producing γδT lymphocytes (IL17-γδTcells rather than to a decrease in Th17 cells. In summary, we here show that iNKT cells play a protective role against Salmonella-enterocolitis and Salmonella-induced ReA by downregulating IL17-γδTcells.

  15. Gamma irradiation increase the sensitivity of Salmonella to antibiotics

    International Nuclear Information System (INIS)

    Ben Miloud, Najla; Barkallah, Insaf

    2008-01-01

    In order to study the effect of ionizing radiation on the resistance of Salmonella to antibiotics, four strains of Salmonella were isolated from foods, The different strains used in the present study are (S. Hadar isolate 287, S. Hadar isolate 63, S. Cerro isolate 291, S. Zanzibar isolate 1103), antibiogram analyses were made to test the in vitro-sensitivity of irradiated Salmonella isolates to different antibiotics.The analyse of Control and exposed antibiograms showed that gamma radiation have increased the sensitivity of Salmonella isolates to Cefalotin, Chloramphenicol, Nalidixic acid, Spiramycin and Gentamycin excepted S. Hadar isolate 287 that was resistant to Cefalotin and became sensitive after irradiation. Statistical analyses showed that the effect of different irradiation dose treatment on the antibiotic sensitivity is increasingly significant. The irradiation didn't induce modifications of the sensitivity to other antibiotics,probably because of their nature, of their penetration mode inside the cell or their action way

  16. EFEKTIVITAS AIR REBUSAN DAUN BINAHONG (Anredera cordifolia TERHADAP PERTUMBUHAN Salmonella typhi

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    Ratih Dewi Dwiyanti

    2015-06-01

    Full Text Available Abstract: Typhus is one of acute febrile illness caused by the bacterium Salmonella typhi. Treatment of typhoid fever usually use antibiotics, the use of antibiotics can cause side effects. People today are using treatment with natural ingredients, one of which is Binahong (Anredera cordifolia compounds containing alkaloids, polyphenols, flavonoids, saponin, and anthraquinone is efficacious as an antibacterial. This study aims to determine the effectiveness of the water decoction of leaves Binahong against Salmonella typhi growth in vitro. This type of research is true experiment with posttest study design Only Control Group Design and methods used are diffusion (wells with 5 treatment. The concentration of the cooking water leaves the dgunakan Binahong is 20%, 40%, 60%, 80% and 100%. The result showed inhibition zone water decoction of the leaves Binahong against Salmonella typhi at a concentration of 20%, 40%, 60%, 80% is 0 mm, whereas at 100% concentration obtained inhibition zone of 11 mm. It is concluded that the water decoction of the leaves Binahong at a concentration of 100% has the ability to inhibit the growth of Salmonella typhi, but these results have not been effective because it is still in the category of resistance. It is suggested for further research to increase the concentration of water decoction of the leaves binahong or use alcohol extract of leaves binahong to inhibit the growth of Salmonella typhi. Keywords: Water decoction of leaves Binahong, Salmonella typhi, antibacterial. Abstrak: Penyakit tifus atau dikenal dengan demam tifoid atau demam enterik adalah salah satu penyakit demam akut yang disebabkan oleh bakteri Salmonella typhi. Pengobatan demam tifoid biasanya menggunakan antibiotik, penggunaan antibiotik dapat menimbulkan efek samping. Masyarakat saat ini banyak menggunakan pengobatan dengan bahan alami, salah satunya adalah Binahong (Anredera cordifolia yang mengandung senyawa Alkaloid, Polifenol, Flavonoid

  17. Prevalence of Salmonella spp. in environmental samples from table egg barns in Alberta.

    Science.gov (United States)

    St Amand, Joan A; Cassis, Rashed; King, Robin K; Annett Christianson, Colleen B

    2017-12-01

    Some Salmonella spp. are zoonotic, a frequent cause of foodborne illness in Canada, and known to infect humans through contaminated poultry and poultry products. Certain serotypes of Salmonella spp. have been demonstrated to be vertically transmitted from hen to egg. The incidence of Salmonella spp. isolation in the flock has been correlated to its isolation from the environment. Twenty-one producers were enrolled in this study to examine the occurrence of Salmonella spp. in 48 table egg layer flocks housed in 35 barns in Alberta. The purpose of this study was to: (i) identify Salmonella serotypes isolated from the environment of table egg layer facilities in Alberta and (ii) record the prevalence of Salmonella spp. across eight defined environmental sampling points. Salmonella spp. were isolated from the environment of 20/35 barns representing 29/48 flocks. The most common serotypes isolated were S. Heidelberg, S. Kentucky and S. Mbandaka. The order of most to least contaminated sample location was manure belts (54.1%), feeders (47.9%), feed motors (45.8%), egg belts and walls (41.7%), fans (35.0%), cage bottoms (31.3%) and lobbies (27.1%). Salmonella spp. were isolated from 7/7 barns post cleaning and disinfection, demonstrating the persistence of this organism in the environment and the need for effective eradication protocols.

  18. Current trends of antimicrobial susceptibility of typhoidal salmonellae isolated at tertiary care hospital

    International Nuclear Information System (INIS)

    Zehra, N.M.; Irfan, F.

    2017-01-01

    To determine the current trend of antimicrobial susceptibility of typhoidal Salmonellae. Study Design: Descriptive cross-sectional study. Place and Duration of Study: The study was carried out in the Department of Microbiology, PNS Shifa Hospital, Karachi, from January 2014 to December 2015. Methodology: Blood culture samples received from the wards and outpatient departments were included. Isolates of Salmonella were dealt with standard microbiological procedures. The antimicrobial sensitivity against the typhoidal Salmonellae was determined using Kirby-Bauer disc diffusion method as per the guidelines of Clinical and Laboratory Standards Institute (2013). Results: A total of 460 typhoidal Salmonellae were isolated; out of which 270 were Salmonella typhi and 190 were Salmonella paratyphiA. The percentage of MDR isolates of S. typhi was 57% and that of S. paratyphiA was 42%. None of the isolates were resistant to ceftriaxone, while sensitivity to ciprofloxacin (07% and 0% for S. typhiand S. paratyphiA, respectively) was very low. Conclusion: There is high percentage of MDR isolates of typhoidal Salmonellae in our region. The antimicrobial sensitivity of typhoidal Salmonellae to conventional agent has not improved enough to recommend their empirical use. There is almost complete resistance to fluoroquinolones as well, leaving very limited available treatment options. (author)

  19. Antimicrobial resistance among Salmonella enterica serovar Infantis from broiler carcasses in Serbia

    Science.gov (United States)

    Nikolić, A.; Baltić, T.; Velebit, B.; Babić, M.; Milojević, L.; Đorđević, V.

    2017-09-01

    This study aimed to investigate antimicrobial resistance of Salmonella Infantis isolates from poultry carcasses in Serbia. A total of 48 Salmonella isolates were examined for antimicrobial resistance. A panel of 10 antibiotics was selected for testing. Isolates showed resistance to sulfamethoxazole, ceftazidime and cefotaxime (100%). However, the highest number of Salmonella Infantis isolates were sensitive to chloramphenicol. The usage of antibiotics in food producing animals could result in antimicrobial resistance pathogenic bacteria especially Salmonella spp. in poultry, which may be transmitted to humans through the food chain and increase risk of treatment failures.

  20. A second wave of Salmonella T3SS1 activity prolongs the lifespan of infected epithelial cells.

    Directory of Open Access Journals (Sweden)

    Ciaran E Finn

    2017-04-01

    Full Text Available Type III secretion system 1 (T3SS1 is used by the enteropathogen Salmonella enterica serovar Typhimurium to establish infection in the gut. Effector proteins translocated by this system across the plasma membrane facilitate invasion of intestinal epithelial cells. One such effector, the inositol phosphatase SopB, contributes to invasion and mediates activation of the pro-survival kinase Akt. Following internalization, some bacteria escape from the Salmonella-containing vacuole into the cytosol and there is evidence suggesting that T3SS1 is expressed in this subpopulation. Here, we investigated the post-invasion role of T3SS1, using SopB as a model effector. In cultured epithelial cells, SopB-dependent Akt phosphorylation was observed at two distinct stages of infection: during and immediately after invasion, and later during peak cytosolic replication. Single cell analysis revealed that cytosolic Salmonella deliver SopB via T3SS1. Although intracellular replication was unaffected in a SopB deletion mutant, cells infected with ΔsopB demonstrated a lack of Akt phosphorylation, earlier time to death, and increased lysis. When SopB expression was induced specifically in cytosolic Salmonella, these effects were restored to levels observed in WT infected cells, indicating that the second wave of SopB protects this infected population against cell death via Akt activation. Thus, T3SS1 has two, temporally distinct roles during epithelial cell colonization. Additionally, we found that delivery of SopB by cytosolic bacteria was translocon-independent, in contrast to canonical effector translocation across eukaryotic membranes, which requires formation of a translocon pore. This mechanism was also observed for another T3SS1 effector, SipA. These findings reveal the functional and mechanistic adaptability of a T3SS that can be harnessed in different microenvironments.

  1. Salmonella from Baby Turtles

    Centers for Disease Control (CDC) Podcasts

    2017-01-09

    Dr. Stacey Bosch, a veterinarian with CDC, discusses her article on Salmonella infections associated with baby turtles.  Created: 1/9/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 1/9/2017.

  2. Penerapan Metode Dempster Shafer Untuk Mendiagnosa Penyakit Dari Akibat Bakteri Salmonella

    Directory of Open Access Journals (Sweden)

    Mikha Dayan Sinaga

    2016-12-01

    Full Text Available Infeksi dari bakteri Samonella dapat menyerang saluran gastrointestin yang mencakup perut, usus halus, dan usus besar atau kolon. Beberapa spesies salmonella dapat menyebabkan infeksi melalui makanan. Termasuk ke dalamnya adalah Salmonella Typhi yang mengakibatkan penyakit tifus, dan Salmonella Shigella yang mengakibatkan penyakit disentri dan diare. Masih banyak orang yang belum mengetahui gejala-gejala dari infeksi bakteri ini serta bagaimana cara untuk mendiagnosa dengan nilai kepastian yang tinggi. Untuk dapat mengetahui tingkat kepastian infeksi bakteri ini peneliti menggunakan metode Dempster-Shafer. Metode ini dipilih karena metode ini dianggap mampu untuk memberikan tingkat kepastian yang tinggi. Metode Dempster-Shafer adalah representasi, kombinasi dan propogasi ketidakpastian, dimana teori ini memiliki beberapa karakteristik yang secara instutif sesuai dengan cara berfikir seorang pakar, namun dasar matematika yang kuat. Hasil dari penelitian ini adalah untuk membuat aplikasi sistem pakar yang dapat mendiagnosa bakteri dari akibat bakteri salmonella dengan menggunakan metode Dempster Shafer. Kata Kunci  : Sistem Pakar,Metode Dempster Shafer, Bakteri Salmonella.

  3. Relationship among fecal coliforms, Escherichia coli, and Salmonella spp. in shellfish.

    Science.gov (United States)

    Hood, M A; Ness, G E; Blake, N J

    1983-01-01

    The relationship of fecal coliforms, Escherichia coli, and Salmonella spp. was examined in freshly harvested and stored shellfish. In 16 of 40 freshly collected oyster samples, fecal coliform levels were above the recommended wholesale level suggested by the National Shellfish Sanitation Program (less than or equal to 230/100 g), and Salmonella spp. were present in three of these samples. Salmonella spp. were not, however, present in any sample containing less than 230 fecal coliforms per 100 g. Analysis of the data suggests that low fecal coliform levels in both fresh and stored oysters are good indicators of the absence of Salmonella spp., but that high levels of fecal coliforms are somewhat limited in predicting the presence of Salmonella spp. E. coli levels correlated very strongly with fecal coliform levels in both fresh and stored oysters and clams, suggesting that there is no advantage in replacing fecal coliforms with E. coli as an indicator of shellfish quality.

  4. Occurrence of Salmonella spp. in broiler chicken carcasses and their susceptibility to antimicrobial agents Ocorrência de Salmonella spp. em carcaças de frango e sua suscetibilidade a agentes antimicrobianos

    Directory of Open Access Journals (Sweden)

    Dalila Angélica Moliterno Duarte

    2009-09-01

    Full Text Available The present study was carried out to evaluate the occurrence of Salmonellae in broiler chicken carcasses and to determine the antimicrobial resistance profile of the isolated strains. Twenty-five out of the 260 broiler chicken carcasses samples (9.6% were positive for Salmonella. S. Enteritidis was the most frequent serovar. Nineteen Salmonella isolates were tested for antimicrobial resistance, and the results indicated that 94.7% were resistant to at least one antimicrobial agent. Resistance to streptomycin (73.7%, nitrofurantoin (52.3%, tetracycline (31.6%, and nalidixic acid (21% were the prevalent amongst Salmonella strains tested.O presente estudo teve como objetivo verificar a ocorrência de Salmonellae em amostras de carcaças de frango e a suscetibilidade dos isolados a agentes antimicrobianos. Das 260 carcaças analisadas, 25 (9,6% foram positivas para Salmonella. Salmonella Enteritidis foi o sorovar predominante. Com relação à suscetibilidade a agentes antimicrobianos, 94,7% das cepas de Salmonella testadas, apresentaram resistência a um ou mais agentes antimicrobianos. Os perfís de resistência mais comumente observados entre os isolados foram a resistência à estreptomicina (73,7%, nitrofurantoína (52,3%, tetraciclina (31,6% e ácido nalidíxico (21%.

  5. Correlation between Salmonella and hygiene indicators in the Danish fresh pork chain

    DEFF Research Database (Denmark)

    Aabo, Søren; Sandø, G.; Hansen, Tina Beck

    ,569 samples from cutting plants, and in 1,232 samples from retail supermarkets and butcher shops sampled from June 2010 to March 2011 and associates this to two hygiene indicators, enterococci and Enterobacteriaceae. In six large cutting plants, Salmonella was isolated from 1.3 % compared 3.7 % of samples...... in 12 smaller plants. Process hygiene was described by quantifying Enterobacteriaceae and enterococci in samples and high levels of both were mostly seen for smaller plants. Enterococci counts varied more between plants than Enterobacteriaceae. Occurrence of Salmonella was positively correlated...... supermarkets and 12 % from butcher shops contained enterococci. Samples containing enterococci were six times more likely to contain Salmonella whereas no correlation was found between Enterobacteriaceae and Salmonella in retail samples. In conclusion, presence of Salmonella was associated with lower hygiene...

  6. Characterization and specificity of probiotics to prevent salmonella infection in mice

    Directory of Open Access Journals (Sweden)

    Ana Andino

    2014-08-01

    Full Text Available Background: Probiotic strains of bacteria can prevent Salmonella from causing disease by preventing the pathogen from colonizing the intestines. Two strains of probiotics, Lactobacillus acidophilius and Pediococcus spp, that were obtained from poultry fecal samples have been shown to be efficacious in poultry. The objective of this study was to determine if these strains of probiotics could prevent salmonellosis in a mouse model. Methods: First, both strains of probiotics were evaluated for in vitro efficacy to inhibit the growth of and interfere with virulence gene regulation in Salmonella enterica. For in vivo efficacy, mice was used which models Typhoid illness. Mice were divided into 2 groups: Control and treatment, Lactobacillus and Pediococcus (LP; 108 Log CFU. Two experiments were conducted. In the first experiment, the mice were treated with LP in water for the first two days of the experiment and challenged with Salmonella at day three. In the second experiment, the LP treatment was given in the water for 10 days and challenge was performed on day 11. In both experiments, at day 20 post-challenge, all mice were sacrificed, intestinal tracts and organs removed and cultured for Salmonella. Results: The probiotic strains inhibited the growth of Salmonella and down-regulation of virulence genes was noted, but dependent on the strain of Salmonella being evaluated. For the in vivo experiment, the probiotics did not afford the mice protection from infection and increasing the length of time the probiotics were administered did not improve the efficacy of the probiotics. Conclusions: It appears that these strains of probiotic bacteria are effective against Salmonella in vitro. However, these isolates did not afford protection from Salmonella infection to mice which may be due to host specifity as these isolates were obtained from poultry

  7. Geographical distribution of salmonella infected pig, cattle and sheep herds in Sweden 1993-2010

    Directory of Open Access Journals (Sweden)

    Skog Lars

    2011-10-01

    Full Text Available Abstract Background The Swedish salmonella control programme covers the entire production chain, from feed to food. All salmonella serotypes are notifiable. On average, less than 20 cases of salmonella in food-producing animals are reported every year. In some situations, the cases would be expected to cluster geographically. The aim of this study was to illustrate the geographic distribution of the salmonella cases detected in pigs, cattle and sheep. Methods Data on all herds with pigs, cattle and sheep found to be infected with salmonella during the time period from 1993 to 2010 were obtained from the Swedish Board of Agriculture. Using the ArcGIS software, various maps were produced of infected herds, stratified on animal species as well as salmonella serotype. Based on ocular inspection of all maps, some were collapsed and some used separately. Data were also examined for temporal trends. Results No geographical clustering was observed for ovine or porcine cases. Cattle herds infected with Salmonella Dublin were mainly located in the southeast region and cattle herds infected with Salmonella Typhimurium in the most southern part of the country. Some seasonal variation was seen in cattle, but available data was not sufficient for further analyses. Conclusions Analyses of data on salmonella infected herds revealed some spatial and temporal patterns for salmonella in cattle. However, despite using 18 years' of data, the number of infected herds was too low for any useful statistical analyses.

  8. Analysis of Salmonella sp bacterial contamination on Vannamei Shrimp using binary logit model approach

    Science.gov (United States)

    Oktaviana, P. P.; Fithriasari, K.

    2018-04-01

    Mostly Indonesian citizen consume vannamei shrimp as their food. Vannamei shrimp also is one of Indonesian exports comodities mainstay. Vannamei shrimp in the ponds and markets could be contaminated by Salmonella sp bacteria. This bacteria will endanger human health. Salmonella sp bacterial contamination on vannamei shrimp could be affected by many factors. This study is intended to identify what factors that supposedly influence the Salmonella sp bacterial contamination on vannamei shrimp. The researchers used the testing result of Salmonella sp bacterial contamination on vannamei shrimp as response variable. This response variable has two categories: 0 = if testing result indicate that there is no Salmonella sp on vannamei shrimp; 1 = if testing result indicate that there is Salmonella sp on vannamei shrimp. There are four factors that supposedly influence the Salmonella sp bacterial contamination on vannamei shrimp, which are the testing result of Salmonella sp bacterial contamination on farmer hand swab; the subdistrict of vannamei shrimp ponds; the fish processing unit supplied by; and the pond are in hectare. This four factors used as predictor variables. The analysis used is Binary Logit Model Approach according to the response variable that has two categories. The analysis result indicates that the factors or predictor variables which is significantly affect the Salmonella sp bacterial contamination on vannamei shrimp are the testing result of Salmonella sp bacterial contamination on farmer hand swab and the subdistrict of vannamei shrimp ponds.

  9. Identification by PCR of non-typhoidal Salmonella enterica serovars associated with invasive infections among febrile patients in Mali.

    Directory of Open Access Journals (Sweden)

    Sharon M Tennant

    2010-03-01

    Full Text Available In sub-Saharan Africa, non-typhoidal Salmonella (NTS are emerging as a prominent cause of invasive disease (bacteremia and focal infections such as meningitis in infants and young children. Importantly, including data from Mali, three serovars, Salmonella enterica serovar Typhimurium, Salmonella Enteritidis and Salmonella Dublin, account for the majority of non-typhoidal Salmonella isolated from these patients.We have extended a previously developed series of polymerase chain reactions (PCRs based on O serogrouping and H typing to identify Salmonella Typhimurium and variants (mostly I 4,[5],12:i:-, Salmonella Enteritidis and Salmonella Dublin. We also designed primers to detect Salmonella Stanleyville, a serovar found in West Africa. Another PCR was used to differentiate diphasic Salmonella Typhimurium and monophasic Salmonella Typhimurium from other O serogroup B, H:i serovars. We used these PCRs to blind-test 327 Salmonella serogroup B and D isolates that were obtained from the blood cultures of febrile patients in Bamako, Mali.We have shown that when used in conjunction with our previously described O-serogrouping PCR, our PCRs are 100% sensitive and specific in identifying Salmonella Typhimurium and variants, Salmonella Enteritidis, Salmonella Dublin and Salmonella Stanleyville. When we attempted to differentiate 171 Salmonella Typhimurium (I 4,[ 5],12:i:1,2 strains from 52 monophasic Salmonella Typhimurium (I 4,[5],12:i:- strains, we were able to correctly identify 170 of the Salmonella Typhimurium and 51 of the Salmonella I 4,[5],12:i:- strains.We have described a simple yet effective PCR method to support surveillance of the incidence of invasive disease caused by NTS in developing countries.

  10. Identification of Salmonella serovars isolated from live molluscan shellfish and their significance in the marine environment.

    Science.gov (United States)

    Martinez-Urtaza, Jaime; Saco, Montserrat; Hernandez-Cordova, Gustavo; Lozano, Antonio; Garcia-Martin, Oscar; Espinosa, Joaquin

    2003-02-01

    A study on the presence of Salmonella spp. in live molluscs was performed, which included a description of the different serovars isolated and their relationship to the marine environment. A total of 2,980 samples of shellfish from Galicia (N.W. Spain) were tested for the presence of Salmonella spp. between September 1998 and August 2001. The overall incidence of Salmonella was 1.8% and showed a slight rise during the 3 years of the study. Mussels and oysters presented a higher incidence than clams and cockles, possibly because of their distinct growing habitat. A seasonal pattern was noted for the isolation of Salmonella spp.: 54% of the isolations were detected from September to November. That nearly 67% of the total Salmonella was isolated from shellfish with fecal coliform levels fecal coliforms do not necessarily indicate the absence of Salmonella. A total of nine serovars were found in the 54 Salmonella isolated. Salmonella Senftenberg was the most frequent (50%), followed by Salmonella Typhimurium (18%) and Salmonella Agona (17%). Salmonella Senftenberg was detected frequently during the year, whereas the remaining serovars were detected only on occasional contamination events.

  11. Colicinogeny in Salmonella serovars isolated in Brazil

    Directory of Open Access Journals (Sweden)

    Leila Carvalho Campos

    1988-06-01

    Full Text Available A study of colicinogeny was made in 748 strains of Salmonella (97 serovars isolated from different sources; human (291, animal (119, environmental (141, food (102 and animal feed (95. Colicin production was detected in 64 strains (8.6%, particularly isolated from foods (30.4%. Col. E1 (53 and Ia (44 were the most frequently observed, especially in S. agona for environment and food sources. Col V production was identified in 5 strains of S. typhimurium within 8 producer cultures isolated from humans. Its relationship with the sources and serovars of Salmonella are discussed.Investigou-se a produção de colicina em 748 amostras de Salmonella (97 sorovares advindas de díferentes fontes: humana (291, animal (119, ambiental (141, de alimentos (102 e rações (95. Detectaram-se 64 amostras (8,6% colicinogênicas, particularmente isoladas de alimentos (30,4%. ColE1 (53 e Ia (44 foram as mais freqüentes, especialmente no sorovar S, agona, de origem ambiental e de alimentos. Identificou-se também a produção de col V em 5 amostras de S. typhimurium dentre 8 culturas produtoras de origem humana. Discute-se a relação entre a capacidade colicinogênica e as fontes e sorovares de Salmonella.

  12. Salmonella detection in poultry samples. Comparison of two commercial real-time PCR systems with culture methods for the detection of Salmonella spp. in environmental and fecal samples of poultry.

    Science.gov (United States)

    Sommer, D; Enderlein, D; Antakli, A; Schönenbrücher, H; Slaghuis, J; Redmann, T; Lierz, M

    2012-01-01

    The efficiency of two commercial PCR methods based on real-time technology, the foodproof® Salmonella detection system and the BAX® PCR Assay Salmonella system was compared to standardized culture methods (EN ISO 6579:2002 - Annex D) for the detection of Salmonella spp. in poultry samples. Four sample matrices (feed, dust, boot swabs, feces) obtained directly from poultry flocks, as well as artificially spiked samples of the same matrices, were used. All samples were tested for Salmonella spp. using culture methods first as the gold standard. In addition samples spiked with Salmonella Enteridis were tested to evaluate the sensitivity of both PCR methods. Furthermore all methods were evaluated in an annual ring-trial of the National Salmonella Reference Laboratory of Germany. Salmonella detection in the matrices feed, dust and boot swabs were comparable in both PCR systems whereas the results from feces differed markedly. The quality, especially the freshness, of the fecal samples had an influence on the sensitivity of the real-time PCR and the results of the culture methods. In fresh fecal samples an initial spiking level of 100cfu/25g Salmonella Enteritidis was detected. Two-days-dried fecal samples allowed the detection of 14cfu/25g. Both real- time PCR protocols appear to be suitable for the detection of Salmonella spp. in all four matrices. The foodproof® system detected eight samples more to be positive compared to the BAX® system, but had a potential false positive result in one case. In 7-days-dried samples none of the methods was able to detect Salmonella likely through letal cell damage. In general the advantage of PCR analyses over the culture method is the reduction of working time from 4-5 days to only 2 days. However, especially for the analysis of fecal samples official validation should be conducted according to the requirement of EN ISO6579:2002 - Annex D.

  13. Antibiotic susceptibility of Salmonella spp.: a comparison of two surveys with a 5 years interval

    Directory of Open Access Journals (Sweden)

    Gordana Mijović

    2012-02-01

    Full Text Available Salmonella infections are one of the major global public health problems. During the last decade, antibiotic resistance and multiresistance of Salmonella spp. have increased a great deal, especially in developing countries with an increased and indiscriminate use of antibiotics in the treatment of humans and animals. This study aims to investigate and compare antimicrobial susceptibility patterns of Salmonella during 2005 and 2010.A total of 186 Salmonella strain during 2005 and 140 Salmonella strain during 2010 were isolated from stool specimens using standard methods. The isolates were confirmed as Salmonella by using a battery of biochemical reactions. Specific antisera were used for serologic characterization of Salmonella strain. Antimicrobial susceptibility testing was performed by standard disk diffusion method using ampicillin, trimethoprim-sulfamethoxasole, ceftriaxon, chloramphenicol, nalidixic acid and ciprofloxacin.One hundred eighty (96.8% of 186 isolated Salmonella strains in 2005, and 133 (95% of 140 isolated Salmonella strain in 2010 are recognized as Salmonella Enteritidis. Sensitivity of Salmonella isolates during 2005 and 2010 were 91.9% and 92.9% to ampicillin, 95.7% and 97.1% to trimethoprim-sulfamethoxasole, 99.5% and 100% to chloramphenicol, 99.5% and 100% to ciprofloxacin, 98.9% and 97.1% to ceftriaxon, 73.1% and 95.7% to nalidixic acid, respectively.Sensitivity of Salmonella isolates to all tested antimicrobial agents except to ceftriaxon was been slightly improved over testing period. Resistance rate to ceftriaxon was higher in 2010 than in 2005, and this fact deserves attention. Significantly increase susceptibility rate to nalidixic acid was observed between the two surveys

  14. Prevalence and multidrug resistance pattern of Salmonella isolated from resident wild birds of Bangladesh

    Directory of Open Access Journals (Sweden)

    Abdullah Al Faruq

    2016-10-01

    Full Text Available Aim: Salmonellosis is one of the most common zoonotic diseases, and the presence of antimicrobial resistant Salmonella in wild birds is global public health threat. Throughout the last decades, multidrug resistance of Salmonella spp. has increased, particularly in developing countries. Therefore, a cross-sectional study was conducted to investigate the prevalence of Salmonella spp. and antimicrobial resistance pattern against Salmonella spp. from two species of resident wild birds namely house crow (Corvus splendens and Asian pied starling (Gracupica contra. Materials and Methods: Samples were collected from cloacal swabs of house crows and Asian pied starling for isolating Salmonella spp. (bacteriological culture methods followed by antimicrobial susceptibility testing (disk diffusion method against Salmonella spp. isolates during March to December 2014. Results: The prevalence of Salmonella in Asian pied starling and house crows were 67% and 65%, respectively. Within the category of samples from different species, the variation in prevalence was not varied significantly (p>0.05. Isolated Salmonella spp. was tested for resistance to six different antimicrobial agents. Among six antimicrobial tested, 100% resistance were found to penicillin, oxacillin, and clindamycin followed by erythromycin (50-93%, kanamycin (7-20%, and cephalothin (30-67% from both species of birds. Kanamycin remained sensitive in (70-73%, cephalothin (26-70%, and erythromycin appeared to be (0-30% sensitive against Salmonella spp. isolates. Isolated Salmonella spp. was multidrug resistant up to three of the six antimicrobials tested. Conclusion: It can be said that the rational use of antimicrobials needs to be adopted in the treatment of disease for livestock, poultry, and human of Bangladesh to limit the emergence of drug resistance to Salmonella spp.

  15. Research and identification of pathogenic bacteria 'Salmonella and Listeria' in food

    International Nuclear Information System (INIS)

    Harizi Khalil

    2009-01-01

    The sums propose to evaluate the bacterial contamination of certain food taken randomly by two pathogenic bacteria (Salmonella and Listeria) considering the evolution of the diseases of food oignon. For that 78 food samples of different origins were analysed. 2 stocks of the Listeria kind and 3 stocks of the salmonella kind were insulated and identified by biochemical and molecular tests. The pathogenic isolates were identified by coloration gram, test catalase, insulation on specific culture media and Api (20 E for Salmonella and Api listeria. At the end, the PCR were realized to amplify the gene iap which codes for the protein p60 at listeria as well as a sequence clonee randomly specific of Salmonella.

  16. Silver ion-mediated killing of a food pathogen: Melting curve analysis data of silver resistance genes and growth curve data

    Directory of Open Access Journals (Sweden)

    Kuppan Gokulan

    2017-04-01

    Full Text Available Limited antibacterial activity of silver ions leached from silver-impregnated food contact materials could be due to: 1 the presence of silver resistance genes in tested bacteria; or 2 lack of susceptibility to silver ion-mediated killing in the bacterial strain (K. Williams, L. Valencia, K. Gokulan, R. Trbojevich, S. Khare, 2016 [1]. This study contains data to address the specificity of silver resistance genes in Salmonella Typhimurium during the real time PCR using melting curve analysis and an assessment of the minimum inhibitory concentration of silver ions for Salmonella.

  17. Silver ion-mediated killing of a food pathogen: Melting curve analysis data of silver resistance genes and growth curve data.

    Science.gov (United States)

    Gokulan, Kuppan; Williams, Katherine; Khare, Sangeeta

    2017-04-01

    Limited antibacterial activity of silver ions leached from silver-impregnated food contact materials could be due to: 1) the presence of silver resistance genes in tested bacteria ; or 2) lack of susceptibility to silver ion-mediated killing in the bacterial strain (K. Williams, L. Valencia, K. Gokulan, R. Trbojevich, S. Khare, 2016 [1]). This study contains data to address the specificity of silver resistance genes in Salmonella Typhimurium during the real time PCR using melting curve analysis and an assessment of the minimum inhibitory concentration of silver ions for Salmonella .

  18. Comparison of four sampling methods for the detection of Salmonella in broiler litter.

    Science.gov (United States)

    Buhr, R J; Richardson, L J; Cason, J A; Cox, N A; Fairchild, B D

    2007-01-01

    Experiments were conducted to compare litter sampling methods for the detection of Salmonella. In experiment 1, chicks were challenged orally with a suspension of naladixic acid-resistant Salmonella and wing banded, and additional nonchallenged chicks were placed into each of 2 challenge pens. Nonchallenged chicks were placed into each nonchallenge pen located adjacent to the challenge pens. At 7, 8, 10, and 11 wk of age the litter was sampled using 4 methods: fecal droppings, litter grab, drag swab, and sock. For the challenge pens, Salmonella-positive samples were detected in 3 of 16 fecal samples, 6 of 16 litter grab samples, 7 of 16 drag swabs samples, and 7 of 16 sock samples. Samples from the nonchallenge pens were Salmonella positive in 2 of 16 litter grab samples, 9 of 16 drag swab samples, and 9 of 16 sock samples. In experiment 2, chicks were challenged with Salmonella, and the litter in the challenge and adjacent nonchallenge pens were sampled at 4, 6, and 8 wk of age with broilers remaining in all pens. For the challenge pens, Salmonella was detected in 10 of 36 fecal samples, 20 of 36 litter grab samples, 14 of 36 drag swab samples, and 26 of 36 sock samples. Samples from the adjacent nonchallenge pens were positive for Salmonella in 6 of 36 fecal droppings samples, 4 of 36 litter grab samples, 7 of 36 drag swab samples, and 19 of 36 sock samples. Sock samples had the highest rates of Salmonella detection. In experiment 3, the litter from a Salmonella-challenged flock was sampled at 7, 8, and 9 wk by socks and drag swabs. In addition, comparisons with drag swabs that were stepped on during sampling were made. Both socks (24 of 36, 67%) and drag swabs that were stepped on (25 of 36, 69%) showed significantly more Salmonella-positive samples than the traditional drag swab method (16 of 36, 44%). Drag swabs that were stepped on had comparable Salmonella detection level to that for socks. Litter sampling methods that incorporate stepping on the sample

  19. Food contamination with salmonella and human health in Kinshasa ...

    African Journals Online (AJOL)

    SARAH

    2015-10-31

    Oct 31, 2015 ... Objectives: The objective of this study was to assess the level of salmonella contamination of fish and meat from public markets, meat from ... Material and sampling: Seventy-two samples of fresh fish, 120 samples of meat (beef, ..... prevalence and number of. Salmonella in sausages and their destruction.

  20. Effects of challenge dose on faecal shedding of Salmonella ...

    African Journals Online (AJOL)

    Experimental infection of chickens with Salmonella enteritidis is often achieved by oral inoculation of live bacteria to caged chickens. Less information is available on influence of amount of Salmonella a chicken is exposed to during infection on the proportion that is eventually eliminated in faeces. This study evaluated the ...