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Sample records for attenuated salmonella choleraesuis-mediated

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

    International Nuclear Information System (INIS)

    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 D10 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

  2. An rfaH mutant of Salmonella enterica serovar typhimurium is attenuated in swine and reduces intestinal colonization, fecal shedding, and disease severity due to virulent Salmonella Typhimurium

    Science.gov (United States)

    Swine are often asymptomatic carriers of Salmonella spp., and interventions are needed to limit colonization of swine to enhance food safety and reduce environmental contamination. We evaluated the attenuation and potential vaccine use in pigs of a Salmonella enterica serovar Typhimurium mutant of r...

  3. A live attenuated Salmonella enterica serovar Typhimurium vaccine provides cross-protection against Salmonella serovars to reduce disease severity and pathogen transmission

    Science.gov (United States)

    A live attenuated Salmonella enterica serovar Typhimurium vaccine was developed to confer broad protection against multiple Salmonella serovars to prevent disease and reduce pathogen colonization and shedding. Two vaccine trials were performed in swine to determine the protection afforded by the vac...

  4. Tandem attenuators control expression of the Salmonella mgtCBR virulence operon

    OpenAIRE

    Lee, Eun-Jin; Groisman, Eduardo A.

    2012-01-01

    The mgtCBR operon from Salmonella enterica serovar Typhimurium specifies the virulence protein MgtC, the Mg2+ transporter MgtB and the regulatory peptide MgtR. The mgtCBR transcript includes a long leader region harbouring two short open reading frames (ORFs). Translation of these ORFs is anticipated to impact the formation of particular stem-loop structures and control transcription of the coding region by an attenuation-like mechanism. We previously reported that ORF mgtM enables Salmonella...

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

    International Nuclear Information System (INIS)

    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 1x108 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 60Co 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. Construction of a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA

    Institute of Scientific and Technical Information of China (English)

    Can Xu; Zhao-Shen Li; Yi-Qi Du; Zhen-Xing Tu; Yan-Fang Gong; Jing Jin; Hong-Yu Wu; Guo-Ming Xu

    2005-01-01

    AIM: To construct a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA gene and to detect its immunogenicity.METHODS: Genomic DNA of the standard H pylori strain 17 874 was isolated as the template, hpaA gene fragment was amplified by polymerase chain reaction (PCR) and cloned into pUCmT vector. DNA sequence of the amplified hpaA gene was assayed, then cloned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions. The recombinant plasmid was used to transform competent Escherichia coliDH5α, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-hpaA was used to transform LB5000 and the recombinant plasmid isolated from LB5000 was finally used to transform SL7207. After that, the recombinant strain was grown in vitrorepeatedly. In order to iclentify the immunogenicity of the vaccinein vitro, the recombinant pIRES-hpaA was transfected to COS-7 cells using LipofectamineTM2000, the immunogenicity of expressed HpaA protein was detected with SDS-PAGE and Western blot.RESULTS: The 750-base pair hpaA gene fragment was amplified from the genomic DNA and was consistent with the sequence of H pylori hpaA by sequence analysis. It was confirmed by PCR and restriction enzyme digestion that H pylori hpaA gene was inserted into the eukaryotic expression vector pIRES and a stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying H pylori hpaA gene was successfully constructed and the specific strip of HpaA expressed by pIRES-hpaA was detected through Western blot.CONCLUSION: The recombinant attenuated Salmonella typhimurium DNA vaccine strain expressing HpaA protein with immunogenicity can be constructed and it may be helpful for further investigating the immune action of DNA vaccine in vivo.

  7. Twin-arginine Translocation System (tat) Mutants of Salmonella are Attenuated Due to Envelope Defects, not Respiratory Defects

    OpenAIRE

    Craig, Maureen; Sadik, Adam Y.; Golubeva, Yekaterina A.; Tidhar, Avital; Slauch, James M.

    2013-01-01

    The twin-arginine translocation system (Tat) transports folded proteins across the cytoplasmic membrane and is critical to virulence in Salmonella and other pathogens. Experimental and bioinformatic data indicate that 30 proteins are exported via Tat in Salmonella Typhimurium. However, there are no data linking specific Tat substrates with virulence. We inactivated every Tat-exported protein and determined the virulence phenotype of mutant strains. Though a tat mutant is highly attenuated, no...

  8. Tandem attenuators control expression of the Salmonella mgtCBR virulence operon.

    Science.gov (United States)

    Lee, Eun-Jin; Groisman, Eduardo A

    2012-10-01

    The mgtCBR operon from Salmonella enterica serovar Typhimurium specifies the virulence protein MgtC, the Mg(2+) transporter MgtB and the regulatory peptide MgtR. The mgtCBR transcript includes a long leader region harbouring two short open reading frames (ORFs). Translation of these ORFs is anticipated to impact the formation of particular stem-loop structures and control transcription of the coding region by an attenuation-like mechanism. We previously reported that ORF mgtM enables Salmonella to promote transcription of the mgtC and mgtB coding regions when experiencing a rise in cytoplasmic ATP levels. We now show that the proline codon-rich ORF mgtP mediates an increase in transcription of the mgtC and mgtB coding regions under conditions predicted to decrease the levels of proline-charged tRNA(Pro) . The high ATP and low proline signals act independently in an additive form. Replacing conserved mgtP proline codons with codons specifying other amino acids abolished the response to proline limitation but had no effect on the response to ATP. Substitution of conserved adenine nucleotides in mgtM abolished the response to ATP but had no effect in the response to proline limitation. This provides a singular example of a leader mRNA with tandem attenuators responding to different signals. PMID:22857388

  9. Attenuated Salmonella typhimurium carrying shRNA-expressing vectors elicit RNA interference in murine bladder tumors

    Institute of Scientific and Technical Information of China (English)

    Nan YANG; Sheng-hua LI; Yun-zhe L(U); Li-shan CHEN; Da-ming REN

    2011-01-01

    Aim: To examine whether attenuated Salmonella typhimurium (S typhimurium) could be used as an anti-cancer agent or a tumortargeting vehicle for delivering shRNA-expressing pDNA into cancer cells in a mouse tumor model.Methods: Mouse bladder transitional cancer cell line (BTT-T739) expressing GFP was used, in which the GFP expression level served as an indicator of RNA interference (RNAi). BTT-T739-GFP tumor-bearing mice (4-6 weeks) were treated with S typhimurium carrying plasmids encoding shRNA against gfp or scrambled shRNA. The mRNA and protein expression levels of GFP were assessed 5 d after the bacteria administration, and the antitumor effects of S typhimurium were evaluated.Results: In BTT-T739-GFP tumor-bearing mice, S typhirnurium (1×109 cfu, po) preferentially accumulated within tumors for as long as 40 d, and formed a tumor-to-normal tissue ratio that exceeded 1000/1. S typhimurium carrying plasmids encoding shRNA against gfp inhibited the expression of GFP in tumor cells by 73.4%. Orally delivered S typhimurium significantly delayed tumor growth and prolonged the survival of tumor-bearing mice.Conclusion: This study demonstrates that attenuated S typhimurium can be used for both delivering shRNA-expressing vectors into tumor cells and eliciting RNAi, thus exerting anti-tumor activity, which may represent a new strategy for the treatment of solid tumors.

  10. Salmonella

    Science.gov (United States)

    ... Linked to Small Turtles More Reports, Publications, and Communication Materials Surveillance Salmonella Atlas MMWR Articles References Communication ... Infections Linked to Red and Black Pepper/Italian-Style Meats 2006 through 2009 Outbreaks Saintpaul Infections Linked ...

  11. Evaluation of regulated delayed attenuation strategies for Salmonella enterica serovar Typhi vaccine vectors in neonatal and infant mice.

    Science.gov (United States)

    Shi, Huoying; Wang, Shifeng; Curtiss, Roy

    2013-06-01

    We developed regulated delayed attenuation strategies for Salmonella vaccine vectors. In this study, we evaluated the combination of these strategies in recombinant attenuated Salmonella enterica serovar Typhi and Salmonella enterica serovar Typhimurium vaccine vectors with similar genetic backgrounds in vitro and in vivo. Our goal is to develop a vaccine to prevent Streptococcus pneumoniae infection in newborns; thus, all strains delivered a pneumococcal antigen PspA and the impact of maternal antibodies was evaluated. The results showed that all strains with the regulated delayed attenuated phenotype (RDAP) displayed an invasive ability stronger than that of the S. Typhi vaccine strain, Ty21a, but weaker than that of their corresponding wild-type parental strains. The survival curves of different RDAP vaccine vectors in vitro and in vivo exhibited diverse regulated delayed attenuation kinetics, which was different from S. Typhi Ty21a and the wild-type parental strains. Under the influence of maternal antibody, the persistence of the S. Typhimurium RDAP strain displayed a regulated delayed attenuation trend in nasal lymphoid tissue (NALT), lung, and Peyer's patches, while the persistence of S. Typhi RDAP strains followed the curve only in NALT. The bacterial loads of S. Typhi RDAP strains were lower in NALT, lung, and Peyer's patches in mice born to immune mothers than in those born to naive mothers. In accordance with these results, RDAP vaccine strains induced high titers of IgG antibodies against PspA and against Salmonella lipopolysaccharides. Immunization of mothers with S. Typhi RDAP strains enhanced the level of vaginal mucosal IgA, gamma interferon (IFN-γ), and interleukin 4 (IL-4) and resulted in a higher level of protection against S. pneumoniae challenge. PMID:23616408

  12. Room temperature stabilization of oral, live attenuated Salmonella enterica serovar Typhi-vectored vaccines.

    Science.gov (United States)

    Ohtake, Satoshi; Martin, Russell; Saxena, Atul; Pham, Binh; Chiueh, Gary; Osorio, Manuel; Kopecko, Dennis; Xu, Deqi; Lechuga-Ballesteros, David; Truong-Le, Vu

    2011-03-24

    Foam drying, a modified freeze drying process, was utilized to produce a heat-stable, live attenuated Salmonella Typhi 'Ty21a' bacterial vaccine. Ty21a vaccine was formulated with pharmaceutically approved stabilizers, including sugars, plasticizers, amino acids, and proteins. Growth media and harvesting conditions of the bacteria were also studied to enhance resistance to desiccation stress encountered during processing as well as subsequent storage at elevated temperatures. The optimized Ty21a vaccine, formulated with trehalose, methionine, and gelatin, demonstrated stability for approximately 12 weeks at 37°C (i.e., time required for the vaccine to decrease in potency by 1log(10)CFU) and no loss in titer at 4 and 25°C following storage for the same duration. Furthermore, the foam dried Ty21a elicited a similar immunogenic response in mice as well as protection in challenge studies compared to Vivotif™, the commercial Ty21a vaccine. The enhanced heat stability of the Ty21a oral vaccine, or Ty21a derivatives expressing foreign antigens (e.g. anthrax), could mitigate risks of vaccine potency loss during long-term storage, shipping, delivery to geographical areas with warmer climates or during emergency distribution following a bioterrorist attack. Because the foam drying process is conducted using conventional freeze dryers and can be readily implemented at any freeze drying manufacturing facility, this technology appears ready and appropriate for large scale processing of foam dried vaccines. PMID:21300096

  13. Salmonella

    Science.gov (United States)

    Salmonella are facultative anaerobic Gram-negative non-spore forming rods belonging to the family Enterobacteriaceae. Salmonellosis is a zoonotic and foodborne illness that is usually transmitted by the fecal-oral route estimated to be responsible for 1.4 million cases of human infections in 2009 in...

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

    International Nuclear Information System (INIS)

    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

  15. 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

    2016-05-01

    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. PMID:27060051

  16. Transient Loss of Protection Afforded by a Live Attenuated Non-typhoidal Salmonella Vaccine in Mice Co-infected with Malaria

    OpenAIRE

    Mooney, Jason P.; Lee, Seung-Joo; Lokken, Kristen L.; Nanton, Minelva R.; Nuccio, Sean-Paul; Stephen J McSorley; Tsolis, Renée M.

    2015-01-01

    In immunocompetent individuals, non-typhoidal Salmonella serovars (NTS) are associated with gastroenteritis, however, there is currently an epidemic of NTS bloodstream infections in sub-Saharan Africa. Plasmodium falciparum malaria is an important risk factor for invasive NTS bloodstream in African children. Here we investigated whether a live, attenuated Salmonella vaccine could be protective in mice, in the setting of concurrent malaria. Surprisingly, mice acutely infected with the nonletha...

  17. Construction of attenuated Salmonella typhimurium Strain expressing Helicobacter pylori conservative region of adhesin antigen and its immunogenicity

    Institute of Scientific and Technical Information of China (English)

    Yang Bai; Ya-Li Zhang; Ji-De Wang; Zhao-Shan Zhang; Dian-Yuan Zhou

    2004-01-01

    AIM: To construct a non-resistant and attenuated Salmonella typhimurium (S. typhimurium) strain which expresses conservative region of adhesion AB of Helicobacter pylori (H pylori) and evaluate its immunogenicity.METHODS: The AB gene amplified by PCR was inserted into the expression vector pYA248 containing asd gene and through two transformations introduced into the delta Cya, delta Crp, delta Asd attenuated Salmonella typhimurium strain, constructing balanced lethal attenuated Salmonella typhimurium strains X4072 (pYA248-AB). Bridged ELISA method was used to measure the expression of AB antigen in sonic ate and culture supernatant. According to the method described by Meacock, stability of the recombinant was evaluated. Semi-lethal capacity test was used to evaluate the safety of recombinant. The immunogenicity of recombinant was evaluated with animal experiments.RESULTS: The attenuated S. typhimurium X4072 (pYA248-AB) which expresses AB was successfully constructed.Furthermore, bridged ELISA assay showed that the content of AB in recombinant X4072 (pYA248- AB) culture supematant was higher than that was in thallus lyric liquor. And after recombinant X4072 (pYA248- AB) was cultured for 100generations without selection pressure, the entire recombinant bacteria selected randomly could grow, and the AB antigen was defected positive by ELISA. The growth curve of the recombinant bacteria showed that the growth states of X4072 (pYA248) and X4072 (pYA248-AB) were basically consistent. The survival rate of C57BL/6 was still 100%, at 30 d after mice taking X4072 (pYA248-AB) 1.0×1010 cfu orally. Oral immunization of mice with X4072 (pYA248-AB)induced a specific immune response.CONCLUSION: In vitro recombinant plasmid appears to be stable and experiments on animals showed that the recombinant strains were safe and immunogenic in vitro,which providing a new live oral vaccine candidate for protection and care of H pylori infection.

  18. Construction of recombinant attenuated Salmonella typhimurium DNA vaccine expressing H pylori ureB and IL-2

    Institute of Scientific and Technical Information of China (English)

    Can Xu; Zhao-Shen Li; Yi-Qi Du; Yan-Fang Gong; Hua Yang; Bo Sun; Jing Jin

    2007-01-01

    AIM: To construct a recombinant live attenuated Salmonella typhimurium DNA vaccine encoding H pylori ureB gene and mouse IL-2 gene and to detect its immunogenicity in vitro and in vivo.METHODS: H pylori ureB and mouse IL-2 gene fragments were amplified by potymerase chain reaction (PCR) and cloned into pUCmT vector. DNA sequence of the amplified ureB and IL-2 genes was assayed, then cloned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions resulting in pIRES-ureB and pIRES-ureB-IL-2. The recombinant plasmids were used to transform competent E. Coli DH5a, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-ureB and pIRES-ureB-IL-2 were used to transform LB5000 and the recombinant plasmids extracted from LB5000 were finally introduced into the final host SL7207. After that, recombinant strains were grown in vitro repeatedly. In order to detect the immunogenicity of the vaccine in vitro, pIRES-ureB and pIRES-ureB-IL-2 were transfected to COS-7 cells using Lipofectamine TM 2000, the immunogenicity of expressed UreB and IL-2 proteins was assayed with SDS-PAGE and Western blot. C57BL/6 mice were orally immunized with 1 x 108 recombinant attenuated Salmonella typhimurium DNA vaccine. Four weeks after vaccination, mice were challenged with 1 x 107 CFU of live Hpylori SSI. Mice were sacrificed and the stomach was isolated for examination of H pylori 4 wk post-challenge.RESULTS: The 1700 base pair ureB gene fragment amplified from the genomic DNA was consistent with the sequence of H pylori ureB by sequence analysis. The amplified 510 base pair fragment was consistent with the sequence of mouse IL-2 in gene bank. It was confirmed by PCR and restriction enzyme digestion that H pylori ureB and mouse IL-2 genes were inserted into the eukaryotic expression vector pIRES. The experiments in vitro snowed that stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying

  19. Twin-arginine translocation system (tat) mutants of Salmonella are attenuated due to envelope defects, not respiratory defects.

    Science.gov (United States)

    Craig, Maureen; Sadik, Adam Y; Golubeva, Yekaterina A; Tidhar, Avital; Slauch, James M

    2013-09-01

    The twin-arginine translocation system (Tat) transports folded proteins across the cytoplasmic membrane and is critical to virulence in Salmonella and other pathogens. Experimental and bioinformatic data indicate that 30 proteins are exported via Tat in Salmonella Typhimurium. However, there are no data linking specific Tat substrates with virulence. We inactivated every Tat-exported protein and determined the virulence phenotype of mutant strains. Although a tat mutant is highly attenuated, no single Tat-exported substrate accounts for this virulence phenotype. Rather, the attenuation is due primarily to envelope defects caused by failure to translocate three Tat substrates, the N-acetylmuramoyl-l-alanine amidases, AmiA and AmiC, and the cell division protein, SufI. Strikingly, neither the amiA amiC nor the sufI mutations alone conferred any virulence defect. Although AmiC and SufI have previously been localized to the divisome, the synthetic phenotypes observed are the first to suggest functional overlap. Many Tat substrates are involved in anaerobic respiration, but we show that a mutant completely deficient in anaerobic respiration retains full virulence in both the oral and systemic phases of infection. Similarly, an obligately aerobic mutant is fully virulent. These results suggest that in the classic mouse model of infection, S. Typhimurium is replicating only in aerobic environments. PMID:23822642

  20. Oral vaccination of mice with Trichinella spiralis nudix hydrolase DNA vaccine delivered by attenuated Salmonella elicited protective immunity.

    Science.gov (United States)

    Liu, Pei; Wang, Zhong Quan; Liu, Ruo Dan; Jiang, Peng; Long, Shao Rong; Liu, Li Na; Zhang, Xin Zhuo; Cheng, Xiang Chao; Yu, Chuan; Ren, Hui Jun; Cui, Jing

    2015-06-01

    We have previously reported that Trichinella spiralis Nudix hydrolase (TsNd) bound to intestinal epithelial cells (IECs), and the vaccination of mice with recombinant TsNd protein (rTsNd) produced a partial protective immunity against challenge infection in mice. In this study, the full-length cDNA sequence of TsNd gene was cloned into the eukaryotic expression plasmid pcDNA3.1, and the recombinant TsNd DNA was transformed into attenuated Salmonella typhimurium strain ⊿cyaSL1344. Oral immunization of mice with TsNd/S. typhimurium elicited a significant local mucosal IgA response and a systemic Th1/Th2 immune response. Cytokine profiling also showed a significant increase in the Th1 (IFN-γ, IL-2) and Th2 (IL-4, 10) responses in splenocytes of immunized mice upon stimulation with the rTsNd. The oral immunization of mice with TsNd/S. typhimurium displayed a statistically significant 73.32% reduction in adult worm burden and a 49.5% reduction in muscle larvae after challenge with T. spiralis muscle larvae, compared with PBS control group. Our results demonstrated that TsNd DNA delivered by attenuated live S. typhimurium elicited a local IgA response and a mixed Th1/Th2 immune response, and produced a partial protection against T. spiralis infection in mice. PMID:25733024

  1. Construction, genotypic and phenotypic characterization, and immunogenicity of attenuated DeltaguaBA Salmonella enterica serovar Typhi strain CVD 915.

    Science.gov (United States)

    Wang, J Y; Pasetti, M F; Noriega, F R; Anderson, R J; Wasserman, S S; Galen, J E; Sztein, M B; Levine, M M

    2001-08-01

    A promising live attenuated typhoid vaccine candidate strain for mucosal immunization was developed by introducing a deletion in the guaBA locus of pathogenic Salmonella enterica serovar Typhi strain Ty2. The resultant DeltaguaBA mutant, serovar Typhi CVD 915, has a gene encoding resistance to arsenite replacing the deleted sequence within guaBA, thereby providing a marker to readily identify the vaccine strain. CVD 915 was compared in in vitro and in vivo assays with wild-type strain Ty2, licensed live oral typhoid vaccine strain Ty21a, or attenuated serovar Typhi vaccine strain CVD 908-htrA (harboring mutations in aroC, aroD, and htrA). CVD 915 was less invasive than CVD 908-htrA in tissue culture and was more crippled in its ability to proliferate after invasion. In mice inoculated intraperitoneally with serovar Typhi and hog gastric mucin (to estimate the relative degree of attenuation), the 50% lethal dose of CVD 915 (7.7 x 10(7) CFU) was significantly higher than that of wild-type Ty2 (1.4 x 10(2) CFU) and was only slightly lower than that of Ty21a (1.9 x 10(8) CFU). Strong serum O and H antibody responses were recorded in mice inoculated intranasally with CVD 915, which were higher than those elicited by Ty21a and similar to those stimulated by CVD 908-htrA. CVD 915 also elicited potent proliferative responses in splenocytes from immunized mice stimulated with serovar Typhi antigens. Used as a live vector, CVD 915(pTETlpp) elicited high titers of serum immunoglobulin G anti-fragment C. These encouraging preclinical data pave the way for phase 1 clinical trials with CVD 915. PMID:11447145

  2. Mucosal DNA vaccination with highly attenuated Shigella is superior to attenuated Salmonella and comparable to intramuscular DNA vaccination for T cells against HIV.

    Science.gov (United States)

    Vecino, William H; Morin, Paul M; Agha, Rabia; Jacobs, William R; Fennelly, Glenn J

    2002-07-01

    An immunization strategy using attenuated bacteria to deliver DNA vaccine plasmids to mucosal sites may induce protective T cell responses against sexual HIV transmission. In a murine intranasal (i.n.) immunization model, we demonstrate that transiently persistent Deltaasd Shigella flexneri strain 15D harboring DNA vaccines induces HIV- and SIV-specific gamma interferon (IFN-gamma) producing CD8+ T cells among splenocytes more efficiently than either a longer persisting DeltaaroD Salmonella typhimurium strain SL7207 or transiently persistent S. typhi strain Ty21a harboring DNA vaccines. Also, the frequency of antigen-specific gamma interferon (IFN-gamma) producing cells induced by Shigella 15D harboring a DNA vaccine were comparable to that induced by intramuscular (i.m.) immunization with purified DNA vaccine. Moreover, the magnitude of mucosal and systemic antigen-specific IgA and IgG responses after immunization were dependent upon the route (i.m. vs. i.n.) of inoculation, with i.n. Shigella 15D DNA vaccines generating higher levels of HIV-specific IgA in vaginal washings than i.m. purified DNA vaccine. Deltaasd S. flexneri is a promising vector for mucosal DNA vaccine immunization against HIV. PMID:12036602

  3. Oral infection with the Salmonella enterica serovar Gallinarum 9R attenuated live vaccine as a model to characterise immunity to fowl typhoid in the chicken

    Directory of Open Access Journals (Sweden)

    Beal Richard

    2005-09-01

    Full Text Available Abstract Background Salmonella enterica serovar Gallinarum (S. Gallinarum is the causative agent of fowl typhoid, a severe systemic disease of chickens that results in high mortality amongst infected flocks. Due to its virulence, the immune response to S. Gallinarum is poorly characterised. In this study we have utilised infection by the live attenuated S. Gallinarum 9R vaccine strain in inbred chickens to characterise humoral, cellular and cytokine responses to systemic salmonellosis. Results Infection with 9R results in a mild systemic infection. Bacterial clearance at three weeks post infection coincides with increases in circulating anti-Salmonella antibodies, increased T cell proliferation to Salmonella challenge and increased expression of interferon gamma. These responses peak at four weeks post infection, then decline. Only modest increases of expression of the pro-inflammatory cytokine interleukin-1β were detected early in the infection. Conclusion Infection of chickens with the 9R vaccine strain induces a mild form of systemic salmonellosis. This induces both cellular and humoral immune responses, which peak soon after bacterial clearance. Unlike enteric-associated Salmonella infections the immune response is not prolonged, reflecting the absence of persistence of Salmonella in the gastrointestinal tract. The findings here indicate that the use of the S. Gallinarum 9R vaccine strain is an effective model to study immunity to systemic salmonellosis in the chicken and may be employed in further studies to determine which components of the immune response are needed for protection.

  4. POTENTIAL OF Salmonella typhi ATTENUATED WITH ULTRAVIOLET RAYS AS VACCINE ALTERNATIVE

    Directory of Open Access Journals (Sweden)

    Andreas Putro Ragil Santoso

    2016-03-01

    Full Text Available Salmonella typhi is a Gram-negative intracellular bacterium and causes typhoid fever in humans. The success rate of Berma Vivotif Ty21a vaccine in Indonesia is only 33-66%, while in other countries have been reached up to 100%. The research was conducted in order to determine the potency of local isolate bacteria to stimulate the immune response and the impact of different exposure frequencies on the immune response and the different immune response time when administered by UV-inactivated vaccine.. The results showed that the antibody titer of local isolates irradiated by UV light 10x was 88.76 ± 33.06 IU/mL at week 4 with the lowest antibody titer values about 11.15 ± 9.18 IU/mL was found in the negative control

  5. Plasmid-based Survivin shRNA and GRIM-19 carried by attenuated Salmonella suppresses tumor cell growth

    Institute of Scientific and Technical Information of China (English)

    Yan-Bo Liu1; De-Qi Xu; Ling Zhang1; Ya-Xiong Guo; Li-Fang Gao; Xi-Chun Liu; Li-Juan Zhao; Bao-Feng Guo; Li-Jing Zhao; Xue-Jian Zhao

    2012-01-01

    Persistent activation of Survivin and its overexpression contribute to the formation,progression and metastasis of several different tumor types.Therefore,Survivin is an ideal target for RNA interference mediated-growth inhibition.Blockade of Survivin using specific short hairpin RNAs (shRNA) can significantly reduce prostate tumor growth.RNA interference does not fully ablate target gene expression,owing to the idiosyncrasies associated with shRNAs and their targets.To enhance the therapeutic efficacy of Survivin-specific shRNA,we employed a combinatorial expression of Survivin-specific shRNA and gene associated with retinoid-interferon-induced mortality-19 (GRIM-19).Then,the GRIM-19 coding sequences and Survivin-specific shRNAs were used to create a dual expression plasmid vector and were carried by an attenuated strain of Salmonella enteric serovar typhimurium (S.typhimurium) to treat prostate cancer in vitroand in vivo.We found that the co-expressed Survivin-specific shRNA and GRIM-19synergistically and more effectively inhibited prostate tumor proliferation and survival,when compared with treatment with either single agent alone in vitro and in vivo.This study has provided a novel cancer gene therapeutic approach for prostate cancer.

  6. In vitro Intestinal Mucosal Epithelial Responses to Wild-Type Salmonella Typhi and Attenuated Typhoid Vaccines.

    Science.gov (United States)

    Fiorentino, Maria; Lammers, Karen M; Levine, Myron M; Sztein, Marcelo B; Fasano, Alessio

    2013-01-01

    Typhoid fever, caused by S. Typhi, is responsible for approximately 200,000 deaths per year worldwide. Little information is available regarding epithelium-bacterial interactions in S. Typhi infection. We have evaluated in vitro the effects of wild-type S. Typhi, the licensed Ty21a typhoid vaccine and the leading strains CVD 908-htrA and CVD 909 vaccine candidates on intestinal barrier function and immune response. Caco2 monolayers infected with wild-type S. Typhi exhibited alterations in the organization of tight junctions, increased paracellular permeability, and a rapid decrease in Trans-Epithelial Electrical Resistance as early as 4 h post-exposure. S. Typhi triggered the secretion of interleukin (IL)-8 and IL-6. Caco2 cells infected with the attenuated strains exhibited a milder pro-inflammatory response with minimal disruption of the barrier integrity. We conclude that wild-type S. Typhi causes marked transient alterations of the intestinal mucosa that are more pronounced than those observed with Ty21a or new generation attenuated typhoid vaccine candidates. PMID:23408152

  7. Targeted therapy via oral administration of attenuated Salmonella expression plasmid-vectored Stat3-shRNA cures orthotopically transplanted mouse HCC.

    Science.gov (United States)

    Tian, Y; Guo, B; Jia, H; Ji, K; Sun, Y; Li, Y; Zhao, T; Gao, L; Meng, Y; Kalvakolanu, D V; Kopecko, D J; Zhao, X; Zhang, L; Xu, D

    2012-06-01

    The development of RNA interference-based cancer gene therapies has been delayed due to the lack of effective tumor-targeting delivery systems. Attenuated Salmonella enterica serovar Typhimurium (S. Typhimurium) has a natural tropism for solid tumors. We report here the use of attenuated S. Typhimurium as a vector to deliver shRNA directly into tumor cells. Constitutively activated signal transducer and activator of transcription 3 (Stat3) is a key transcription factor involved in both hepatocellular carcinoma (HCC) growth and metastasis. In this study, attenuated S. Typhimurium was capable of delivering shRNA-expressing vectors to the targeted cancer cells and inducing RNA interference in vivo. More importantly, a single oral dose of attenuated S. Typhimurium carrying shRNA-expressing vectors targeting Stat3 induced remarkably delayed and reduced HCC (in 70% of mice). Cancer in these cured mice did not recur over 2 years following treatment. These data demonstrated that RNA interference combined with Salmonella as a delivery system may offer a novel clinical approach for cancer gene therapy. PMID:22555509

  8. Constitutive expression of the Vi polysaccharide capsular antigen in attenuated Salmonella enterica serovar typhi oral vaccine strain CVD 909.

    Science.gov (United States)

    Wang, J Y; Noriega, F R; Galen, J E; Barry, E; Levine, M M

    2000-08-01

    Live oral Ty21a and parenteral Vi polysaccharide vaccines provide significant protection against typhoid fever, albeit by distinct immune mechanisms. Vi stimulates serum immunoglobulin G Vi antibodies, whereas Ty21a, which does not express Vi, elicits humoral and cell-mediated immune responses other than Vi antibodies. Protection may be enhanced if serum Vi antibody as well as cell-mediated and humoral responses can be stimulated. Disappointingly, several new attenuated Salmonella enterica serovar Typhi oral vaccines (e.g., CVD 908-htrA and Ty800) that elicit serum O and H antibody and cell-mediated responses following a single dose do not stimulate serum Vi antibody. Vi expression is regulated in response to environmental signals such as osmolarity by controlling the transcription of tviA in the viaB locus. To investigate if Vi antibodies can be stimulated if Vi expression is rendered constitutive, we replaced P(tviA) in serovar Typhi vaccine CVD 908-htrA with the constitutive promoter P(tac), resulting in CVD 909. CVD 909 expresses Vi even under high-osmolarity conditions and is less invasive for Henle 407 cells. In mice immunized with a single intranasal dose, CVD 909 was more immunogenic than CVD 908-htrA in eliciting serum Vi antibodies (geometric mean titer of 160 versus 49, P = 0.0007), whereas O antibody responses were virtually identical (geometric mean titer of 87 versus 80). In mice challenged intraperitoneally with wild-type serovar Typhi 4 weeks after a single intranasal immunization, the mortality of those immunized with CVD 909 (3 of 8) was significantly lower than that of control mice (10 of 10, P = 0.043) or mice given CVD 908-htrA (9 of 10, P = 0.0065). PMID:10899868

  9. Keratinocyte growth factor (KGF) gene therapy mediated by an attenuated form of Salmonella typhimurium ameliorates radiation induced pulmonary injury in rats

    International Nuclear Information System (INIS)

    The aim of this study is to investigate the effect of KGF (Keratinocyte growth factor) gene therapy mediated by the attenuated Salmonella typhimurium Ty21a on radiation-induced pulmonary injury in rats model. Sprague-Dawley rats were divided into three groups: TPK group (treated with TPK strain, attenuated Salmonella typhimurium Ty21a-recombined human KGF gene); TP group (treated with TP strain, attenuated Salmonella typhimurium Ty21a-recombined blank plasmid); and Saline group (treated with saline). After intraperitoneal administration for 48 h, the thoraxes of the rats were exposed to X-ray (20 Gy), and the rats were administered again two weeks after radiation. On the 3rd, 5th, 7th, 14th and 28th day after radiation, the rats were sacrificed and lung tissues were harvested. Histological analysis was performed, malondialdehyde (MDA) contents and superoxide dismutase (SOD) activity were detected, mRNA levels of KGF, transforming growth factor β (TGF-β), surfactant protein A (SP-A) and SP-C were measured by Real-time RT-PCR, and their concentrations in the bronchoalveolar lavage fluid (BALF) were quantified with ELISA. Administration of TPK strain improved the pathological changes of the lung on the 28th day. In the TPK group, KGF effectively expressed since the 3rd day, MDA contents decreased and SOD activity increased significantly, on the 7th day and 14th day respectively. SP-A and SP-C expression elevated, whereas TGF-β expression was inhibited in the TPK group. These results suggest that this novel gene therapy of KGF could ameliorate radiation-induced pulmonary injury in rats, and may be a promising therapy for the treatment of radiative pulmonary injury. (author)

  10. Keratinocyte growth factor (KGF) gene therapy mediated by an attenuated form of Salmonella typhimurium ameliorates radiation induced pulmonary injury in rats.

    Science.gov (United States)

    Liu, Chun-Jie; Ha, Xiao-Qin; Jiang, Jun-Jun; Lv, Tong-De; Wu, Chutse

    2011-01-01

    The aim of this study is to investigate the effect of KGF (Keratinocyte growth factor) gene therapy mediated by the attenuated Salmonella typhimurium Ty21a on radiation-induced pulmonary injury in rats model. Sprague-Dawley rats were divided into three groups: TPK group (treated with TPK strain, attenuated Salmonella typhimurium Ty21a-recombined human KGF gene); TP group (treated with TP strain, attenuated Salmonella typhimurium Ty21a-recombined blank plasmid); and Saline group (treated with saline). After intraperitoneal administration for 48 h, the thoraxes of the rats were exposed to X-ray (20 Gy), and the rats were administered again two weeks after radiation. On the 3rd, 5th, 7th, 14th and 28th day after radiation, the rats were sacrificed and lung tissues were harvested. Histological analysis was performed, MDA contents and SOD activity were detected, mRNA levels of KGF, TGF-β, SP-A and SP-C were measured by Real-time RT-PCR, and their concentrations in the BALF were quantified with ELISA. Administration of TPK strain improved the pathological changes of the lung on the 28th day. In the TPK group, KGF effectively expressed since the 3rd day, MDA contents decreased and SOD activity increased significantly, on the 7th day and 14th day respectively. SP-A and SP-C expression elevated, whereas TGF-β expression was inhibited in the TPK group. These results suggest that this novel gene therapy of KGF could ameliorate radiation-induced pulmonary injury in rats, and may be a promising therapy for the treatment of radiative pulmonary injury. PMID:21436609

  11. Attenuated Salmonella typhimurium delivering DNA vaccine encoding duck enteritis virus UL24 induced systemic and mucosal immune responses and conferred good protection against challenge

    Directory of Open Access Journals (Sweden)

    Yu Xia

    2012-07-01

    Full Text Available Abstract Orally delivered DNA vaccines against duck enteritis virus (DEV were developed using live attenuated Salmonella typhimurium (SL7207 as a carrier and Escherichia coli heat labile enterotoxin B subunit (LTB as a mucosal adjuvant. DNA vaccine plasmids pVAX-UL24 and pVAX-LTB-UL24 were constructed and transformed into attenuated Salmonella typhimurium SL7207 resulting SL7207 (pVAX-UL24 and SL7207 (pVAX-LTB-UL24 respectively. After ducklings were orally inoculated with SL7207 (pVAX-UL24 or SL7207 (pVAX-LTB-UL24, the anti-DEV mucosal and systemic immune responses were recorded. To identify the optimum dose that confers maximum protection, we used different doses of the candidate vaccine SL7207 (pVAX-LTB-UL24 during oral immunization. The strongest mucosal and systemic immune responses developed in the SL7207 (pVAX-LTB-UL24 (1011 CFU immunized group. Accordingly, oral immunization of ducklings with SL7207 (pVAX-LTB-UL24 showed superior efficacy of protection (60-80% against a lethal DEV challenge (1000 LD50, compared with the limited survival rate (40% of ducklings immunized with SL7207 (pVAX-UL24. Our study suggests that the SL7207 (pVAX-LTB-UL24 can be a candidate DEV vaccine.

  12. Trichinella spiralis: intranasal immunization with attenuated Salmonella enterica carrying a gp43 antigen-derived 30mer epitope elicits protection in BALB/c mice.

    Science.gov (United States)

    Pompa-Mera, E N; Yépez-Mulia, L; Ocaña-Mondragón, A; García-Zepeda, E A; Ortega-Pierres, G; González-Bonilla, C R

    2011-12-01

    Trichinellosis is a public health problem and is considered an emergent/re-emergent disease in various countries. The etiological agent of trichinellosis is the nematode Trichinella, which infects domestic animals such as pigs and horses, as well as wild animals and humans. A veterinary vaccine could be an option to control the disease in domestic animals. Although several vaccine candidates have shown promising results, a vaccine against trichinellosis remains unavailable to date. Attenuated Salmonella strains are especially attractive live vectors because they elicit mucosal immunity, which is known to be important for the control of Trichinella spiralis infection at the intestinal level and can be administered by oral or intranasal routes. In this study, the autotransporter ShdA was used to display, on the surface of the Salmonella enterica serovar Typhimurium SL3261, the 210-239 amino acid epitope, (designated as Ag30) derived from the 43 kDa glycoprotein of T. spiralis muscle larvae. The fusion protein elicited antibodies in BALB/c mice that were able to recognize the native epitope on the surface of T. spiralis muscle larvae. Mice immunized by intranasal route with the recombinant Salmonella induced a protective immune response against the T. spiralis challenge, reducing by 61.83% the adult burden at day eight postinfection. This immune response was characterized by the induction of antigen-specific IgG1 and of IL-5 production. This study demonstrates the usefulness of Salmonella as a carrier of nematode epitopes providing a surface display system for intestinal parasite vaccine applications. PMID:21907709

  13. Refined live attenuated Salmonella enterica serovar Typhimurium and Enteritidis vaccines mediate homologous and heterologous serogroup protection in mice.

    Science.gov (United States)

    Tennant, Sharon M; Schmidlein, Patrick; Simon, Raphael; Pasetti, Marcela F; Galen, James E; Levine, Myron M

    2015-12-01

    Invasive nontyphoidal Salmonella (NTS) infections constitute a major health problem among infants and toddlers in sub-Saharan Africa; these infections also occur in infants and the elderly in developed countries. We genetically engineered a Salmonella enterica serovar Typhimurium strain of multilocus sequence type 313, the predominant genotype circulating in sub-Saharan Africa. We evaluated the capacities of S. Typhimurium and Salmonella enterica serovar Enteritidis ΔguaBA ΔclpX live oral vaccines to protect mice against a highly lethal challenge dose of the homologous serovar and determined protection against other group B and D serovars circulating in sub-Saharan Africa. The vaccines S. Typhimurium CVD 1931 and S. Enteritidis CVD 1944 were immunogenic and protected BALB/c mice against 10,000 50% lethal doses (LD50) of S. Typhimurium or S. Enteritidis, respectively. S. Typhimurium CVD 1931 protected mice against the group B serovar Salmonella enterica serovar Stanleyville (91% vaccine efficacy), and S. Enteritidis CVD 1944 protected mice against the group D serovar Salmonella enterica serovar Dublin (85% vaccine efficacy). High rates of survival were observed when mice were infected 12 weeks postimmunization, indicating that the vaccines elicited long-lived protective immunity. Whereas CVD 1931 did not protect against S. Enteritidis R11, CVD 1944 did mediate protection against S. Typhimurium D65 (81% efficacy). These findings suggest that a bivalent (S. Typhimurium and S. Enteritidis) vaccine would provide broad protection against the majority of invasive NTS infections in sub-Saharan Africa. PMID:26351285

  14. Enhancement by ampicillin of antibody responses induced by a protein antigen and a DNA vaccine carried by live-attenuated Salmonella enterica serovar Typhi.

    Science.gov (United States)

    Woo, P C; Tsoi, H W; Leung, H C; Wong, L P; Wong, S S; Chan, E; Yuen, K Y

    2000-07-01

    Live-attenuated Salmonella species are effective carriers of microbial antigens and DNA vaccines. In a mouse model, the immunoglobulin M (IgM) and total antibody levels directed toward the lipopolysaccharide of Salmonella enterica serovar Typhi were significantly enhanced at day 21 after oral immunization with live-attenuated serovar Typhi (strain Ty21a) when ampicillin was concomitantly administered (P Ty21a-stimulated lymphocyte proliferation indices for the ampicillin group at day 21 were significantly higher than those for the normal saline (NS) group (P Ty21a per well, respectively). The 50% lethal doses for mice from the ampicillin and NS groups immunized with Ty21a with pBR322 after wild-type serovar Typhi challenge on day 24 were 3.4 x 10(7) and 5.0 x 10(6) CFU, respectively. The fecal bacterial counts for the ampicillin group at days 1, 3, and 5 were significantly lower than those for the NS group (P Ty21a in a larger number of mice from the ampicillin group than from the NS group. Furthermore, the IgG2a levels directed toward tetanus toxoid were significantly enhanced at days 7 and 21 after oral immunization with Ty21a that carried the fragment c of tetanus toxoid when ampicillin was concomitantly administered (P Ty21a that carried the DNA vaccine that encodes hepatitis B surface antigen when ampicillin was concomitantly administered. The present observation may improve the efficacy of the protein antigens and DNA vaccines carried in live-attenuated bacteria, and further experiments should be carried out to determine the best antibiotics and dosage regimen to be used, as well as the best carrier system for individual protein antigens and DNA vaccines. PMID:10882658

  15. Lactic acid bacteria and bifidobacteria attenuate the proinflammatory response in intestinal epithelial cells induced by Salmonella enterica serovar Typhimurium.

    Science.gov (United States)

    Carey, Christine M; Kostrzynska, Magdalena

    2013-01-01

    Inflammation is a physiological response to infections and tissue injury; however, abnormal immune responses can give rise to chronic inflammation and contribute to disease progression. Various dietary components, including probiotic lactic acid bacteria and prebiotics, have the potential to modulate intestinal inflammatory responses. One factor in particular, the chemokine interleukin-8 (IL-8, CXCL-8), is one of the major mediators of the inflammatory response. The purpose of this study was to investigate modulation of the inflammatory host response induced by Salmonella enterica serovar Typhimurium DT104 in the presence of selected probiotics and lactic acid bacteria (LAB) isolated from human sources, dairy products, and farm animals. IL-8 gene expression and protein production in HT-29 cells were evaluated by real-time PCR and ELISA, respectively. Pre-incubation of HT-29 cells with Lactobacillus kefir IM002, Bifidobacterium adolescentis FRP 61, Bifidobacterium longum FRP 68 and FRP 69, Bifidobacterium breve FRP 334, and Leuconostoc mesenteroides IM080 significantly inhibited IL-8 secretion induced by Salmonella Typhimurium DT104. Co-culture of selected probiotics and Salmonella Typhimurium DT104 reduced IL-8 production, while potential probiotics and LAB had no effect on IL-8 secretion in HT-29 cells preincubated with Salmonella Typhimurium DT104 prior to adding probiotics. Lactobacillus kefir IM002 supernatant also significantly reduced IL-8 production. In conclusion, our study suggests that probiotic bifidobacteria and LAB modulate cytokine induction and possess anti-inflammatory properties; however, the effectiveness is strain dependent. PMID:23391223

  16. Virulence determinants of Salmonella Gallinarum biovar Pullorum identified by PCR signature-tagged mutagenesis and the spiC mutant as a candidate live attenuated vaccine.

    Science.gov (United States)

    Geng, Shizhong; Jiao, Xinan; Barrow, Paul; Pan, Zhiming; Chen, Xiang

    2014-01-31

    Salmonella Gallinarum biovar Pullorum (S. Gallinarum biovar Pullorum) is the causative agent of pullorum disease (PD) in chickens which results in considerable economic losses to the poultry industries in developing countries. PCR-Signature Tagged Mutagenesis was used to identify virulence determinants of S. Gallinarum biovar Pullorum and novel attenuated live vaccine candidates for use against this disease. A library of 1800 signature-tagged S. Gallinarum biovar Pullorum mutants was constructed and screened for virulence-associated genes in chickens. The attenuation of 10 mutants was confirmed by in vivo and in vitro competitive index (CI) studies. The transposons were found to be located in SPI-1 (2/10 mutants), SPI-2 (3/10), the virulence plasmid (1/10) and non-SPI genes (4/10). One highly attenuated spiC mutant persisted in spleen and liver for less than 10 days and induced high levels of circulating antibody and protective immunity against oral challenge in young broiler chickens. The spiC mutant is a potential new vaccine candidate for use with chickens against this disease. PMID:24355532

  17. Comparison between Immunization Routes of Live Attenuated Salmonella Typhimurium Strains Expressing BCSP31, Omp3b, and SOD of Brucella abortus in Murine Model

    Science.gov (United States)

    Kim, Won K.; Moon, Ja Y.; Kim, Suk; Hur, Jin

    2016-01-01

    Live, attenuated Salmonella Typhimurium vaccine candidate expressing BCSP31, Omp3b, and SOD proteins of Brucella abortus was constructed. Thirty BALB/c mice were divided equally into three groups, Group A, were intraperitoneally (IP) inoculated with 100 μl of approximately 1.2 × 106 colony-forming units (CFUs)/ml of the Salmonella containing vector only in 100 μl as a control. And groups B and C mice were orally and IP immunized with approximately 1.2 × 109 CFU/ml of the mixture of three delivery strains in 10 μl and IP immunized with approximately 1.2 × 106 CFU/ml of the mixture in 100 μl, respectively. The serum IgG, TNF-α and IFN-γ concentrations in groups B (except Omp3b) and C were significantly higher than those in group A. Following challenge with B. abortus strain 544; challenge strain was detected <103 CFU from the spleen of all mice of group C. These results suggest that IP immunization with the mixture of the vaccine candidate can induce immune responses, and can effectively protect mice against brucellosis. PMID:27148232

  18. The Human Transcriptome During Nontyphoid Salmonella and HIV Coinfection Reveals Attenuated NFκB-Mediated Inflammation and Persistent Cell Cycle Disruption

    Science.gov (United States)

    Schreiber, Fernanda; Lynn, David J.; Houston, Angela; Peters, Joanna; Mwafulirwa, Gershom; Finlay, Brett B.; Brinkman, Fiona S. L.; Hancock, Robert E. W.; Heyderman, Robert S.; Dougan, Gordon

    2011-01-01

    Background. Invasive nontyphoid Salmonella (iNTS) disease is common and severe in adults with human immunodeficiency virus (HIV) infection in Africa. We previously observed that ex vivo macrophages from HIV-infected subjects challenged with Salmonella Typhimurium exhibit dysregulated proinflammatory cytokine responses. Methods. We studied the transcriptional response in whole blood from HIV-positive patients during acute and convalescent iNTS disease compared to other invasive bacterial diseases, and to HIV-positive and -negative controls. Results. During iNTS disease, there was a remarkable lack of a coordinated inflammatory or innate immune signaling response. Few interferon γ (IFNγ)--induced genes or Toll-like receptor/transcription factor nuclear factor κB (TLR/NFκB) gene pathways were upregulated in expression. Ex vivo lipopolysacharide (LPS) or flagellin stimulation of whole blood, however, showed that convalescent iNTS subjects and controls were competent to mount prominent TLR/NFκB-associated patterns of mRNA expression. In contrast, HIV-positive patients with other invasive bacterial infections (Escherichia coli and Streptococcus pneumoniae) displayed a pronounced proinflammatory innate immune transcriptional response. There was also upregulated mRNA expression in cell cycle, DNA replication, translation and repair, and viral replication pathways during iNTS. These patterns persisted for up to 2 months into convalescence. Conclusions. Attenuation of NFκB-mediated inflammation and dysregulation of cell cycle and DNA-function gene pathway expression are key features of the interplay between iNTS and HIV. PMID:21917897

  19. Prime-Boost Immunization Using a DNA Vaccine Delivered by Attenuated Salmonella enterica Serovar Typhimurium and a Killed Vaccine Completely Protects Chickens from H5N1 Highly Pathogenic Avian Influenza Virus▿

    OpenAIRE

    Pan, Zhiming; Zhang, Xiaoming; Geng, Shizhong; Fang, Qiang; You, Meng; Zhang, Lei; Jiao, Xinan; Liu, Xiufan

    2010-01-01

    H5N1 highly pathogenic avian influenza virus (HPAIV) has posed a great threat not only for the poultry industry but also for human health. However, an effective vaccine to provide a full spectrum of protection is lacking in the poultry field. In the current study, a novel prime-boost vaccination strategy against H5N1 HPAIV was developed: chickens were first orally immunized with a hemagglutinin (HA) DNA vaccine delivered by attenuated Salmonella enterica serovar Typhimurium, and boosting with...

  20. Safety and protective efficacy of a spiC and crp deletion mutant of Salmonella gallinarum as a live attenuated vaccine for fowl typhoid.

    Science.gov (United States)

    Cheng, Zhao; Yin, Junlei; Kang, Xilong; Geng, Shizhong; Hu, Maozhi; Pan, Zhiming; Jiao, Xinan

    2016-08-01

    With an aim to develop a safe, immunogenic fowl typhoid (FT) vaccine, the safety and efficacy of 1009ΔspiCΔcrp, a spiC and crp deletion mutant of Salmonella gallinarum, were evaluated in chickens. Three-day-old chickens were intramuscularly immunized with 1009ΔspiCΔcrp (1×10(7)CFU) and boosted 7days later (at 10-days old) with the same dose and via the same route (vaccinated group). The vaccinated group showed no clinical symptoms and no differences in body weight compared to the unvaccinated control group. 1009ΔspiCΔcrp bacteria colonized and persisted in the liver and spleen of vaccinated chickens for >14days, and significant specific humoral and cellular immune responses were induced. Vaccinated chickens were challenged with S. gallinarum strain SG9 at 21days post-immunization (24-day-old chickens), and efficient protection was observed based on the mortality and clinical symptoms, as compared to those in the control group. These results demonstrate that 1009ΔspiCΔcrp can be used as a live attenuated vaccine. PMID:27473974

  1. Generation of an attenuated Salmonella-delivery strains expressing adhesin and toxin antigens for progressive atrophic rhinitis, and evaluation of its immune responses in a murine model.

    Science.gov (United States)

    Byeon, Hoyeon; Hur, Jin; Kim, Bo Ram; Lee, John Hwa

    2014-09-01

    An expression/secretion plasmid containing genes encoding the FimA, CP39, PtfA, ToxA and F1P2 antigens associated with porcine pneumonic pasteurellosis and progressive atrophic rhinitis (PAR) was constructed and harbored in an attenuated Salmonella Typhimurium, which was used as the vaccine candidate. The immune responses induced by this delivery strain were investigated in a murine model. Each antigen secreted from the delivery strain was confirmed by Western blot analysis. Thirty BALB/c mice were divided equally into two groups; group A were intranasally inoculated with the mixture of the five delivery strains, and group B were inoculated with sterile PBS. In group A, all antigen-specific serum IgG were significantly increased compared to those of group B from the 2nd week post-inoculation (WPI) till the 8th WPI. All antigen-specific mucosal IgA in group A were also significantly greater than those of group B. In addition, the significant splenic lymphocyte proliferative responses, the elevations of CD3(+)CD4(+), CD3(+)CD8(+) and B-cell populations, and the induction of IFN-γ expression in group A were observed. In conclusion, the mixture of five delivery strains expressing specific antigen for these diseases was found to be capable of inducing significant humoral and cellular immune responses. PMID:25045826

  2. The efficacy of an inhibin DNA vaccine delivered by attenuated Salmonella choleraesuis on follicular development and ovulation responses in crossbred buffaloes.

    Science.gov (United States)

    Liu, Qing; Han, Li; Rehman, Zia Ur; Dan, Xingang; Liu, Xiaoran; Bhattarai, Dinesh; Yang, Liguo

    2016-09-01

    The aim of this study was to evaluate the efficacy of an inhibin DNA vaccine delivered by attenuated Salmonella choleraesuis on follicular development and ovulation responses in crossbred buffaloes. A total of 158 crossbred buffaloes divided into four groups and were intramuscularly injected with 1×10(10) (T1, n=41), 1×10(9) (T2, n=37), 1×10(8) (T3, n=37) or 0 (C, n=43) CFU/ml bacteria delivered inhibin vaccine in 10ml PBS on day 0 and 14, respectively. All animals were administered with 1000 IU PMSG on day 28, 0.5mg PGF2α on day 30 and 200μg GnRH on day 32. The results showed buffaloes immunized with the bacteria delivered inhibin vaccine had significantly higher titers of anti-inhibin IgG antibody than control group (Pvaccine, coupled with the estrus synchronization protocol, could be used as an alternative approach to improve fertility in crossbred buffaloes. PMID:27449408

  3. Salmonella Prevention

    Science.gov (United States)

    ... Salmonella Reading and Salmonella Abony Infections linked to Alfalfa Sprouts Advice to Consumers & Retailers Case Count Maps ... Signs & Symptoms Key Resources Salmonella Infections Linked to Alfalfa Sprouts from One Contaminated Seed Lot Advice to ...

  4. The Human Transcriptome During Nontyphoid Salmonella and HIV Coinfection Reveals Attenuated NFκB-Mediated Inflammation and Persistent Cell Cycle Disruption

    OpenAIRE

    Schreiber, Fernanda; Lynn, David J.; Houston, Angela; Peters, Joanna; Mwafulirwa, Gershom; Finlay, Brett B.; Brinkman, Fiona S. L.; Hancock, Robert E. W.; Robert S Heyderman; Dougan, Gordon; Gordon, Melita A.

    2011-01-01

    Background.  Invasive nontyphoid Salmonella (iNTS) disease is common and severe in adults with human immunodeficiency virus (HIV) infection in Africa. We previously observed that ex vivo macrophages from HIV-infected subjects challenged with Salmonella Typhimurium exhibit dysregulated proinflammatory cytokine responses. Methods.  We studied the transcriptional response in whole blood from HIV-positive patients during acute and convalescent iNTS disease compared to other invasive bacterial dis...

  5. Construction of a bivalent DNA vaccine co-expressing S genes of transmissible gastroenteritis virus and porcine epidemic diarrhea virus delivered by attenuated Salmonella typhimurium.

    Science.gov (United States)

    Zhang, Yudi; Zhang, Xiaohui; Liao, Xiaodan; Huang, Xiaobo; Cao, Sanjie; Wen, Xintian; Wen, Yiping; Wu, Rui; Liu, Wumei

    2016-06-01

    Porcine transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PEDV) can cause severe diarrhea in newborn piglets and led to significant economic losses. The S proteins are the main structural proteins of PEDV and TGEV capable of inducing neutralizing antibodies in vivo. In this study, a DNA vaccine SL7207 (pVAXD-PS1-TS) co-expressing S proteins of TGEV and PEDV delivered by attenuated Salmonella typhimurium was constructed and its immunogenicity in piglets was investigated. Twenty-day-old piglets were orally immunized with SL7207 (pVAXD-PS1-TS) at a dosage of 1.6 × 10(11) CFU per piglet and then booster immunized with 2.0 × 10(11) CFU after 2 weeks. Humoral immune responses, as reflected by virus neutralizing antibodies and specific IgG and sIgA, and cellular immune responses, as reflected by IFN-γ, IL-4, and lymphocyte proliferation, were evaluated. SL7207 (pVAXD-PS1-TS) simultaneously elicited immune responses against TGEV and PEDV after oral immunization. The immune levels started to increase at 2 weeks after immunization and increased to levels statistically significantly different than controls at 4 weeks post-immunization, peaking at 6 weeks and declined at 8 weeks. The humoral, mucosal, and cellular immune responses induced by SL7207 (pAXD-PS1-TS) were significantly higher than those of the PBS and SL7207 (pVAXD) (p < 0.01). In particular, the levels of IFN-γ and IL-4 were higher than those induced by the single-gene vaccine SL7207 (pVAXD-PS1) (p < 0.05). These results demonstrated that SL7207 (pVAXD-PS1-TS) possess the immunological functions of the two S proteins of TGEV and PEDV, indicating that SL7207 (pVAXD-PS1-TS) is a candidate oral vaccine for TGE and PED. PMID:26980672

  6. Salmonella: Salmonellosis

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Hansen, Trine; Maurischat, Sven; Malorny, Burkhard

    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...

  7. Mucosal immunization with attenuated Salmonella Typhi expressing anthrax PA83 primes monkeys for accelerated serum antibody responses to parenteral PA83 vaccine

    OpenAIRE

    Galen, James E.; Chinchilla, Magaly; Marcela F. Pasetti; Wang, Jin Yuan; Zhao, LiCheng; Arciniega-Martinez, Ivonne; Silverman, David J.; Levine, Myron M.

    2009-01-01

    Salmonella enterica serovar Typhi vaccine strain CVD 908-htrA was genetically engineered for stable plasmid-based expression of protective antigen of anthrax toxin (PA83) fused with the export protein ClyA (ClyA-PA83). The priming potential of CVD 908-htrA expressing ClyA-PA83 was assessed in 12 rhesus and 20 cynomolgus macaques immunized mucosally (intranasally) on days 0 and 14. A parenteral boost with purified PA83 plus alum was given to rhesus macaques on days 42 and 225; cynomolgus monke...

  8. Evidence for transcription attenuation rendering cryptic a sigmaS-dependent promoter of the osmotically regulated proU operon of Salmonella typhimurium.

    OpenAIRE

    Rajkumari, K; Ishihama, A; Gowrishankar, J

    1997-01-01

    The osmotically regulated proU locus in Escherichia coli has two promoters, P1 and P2, that are recognized, respectively, by the sigmaS- and sigma70-bearing RNA polymerase holoenzymes. However, the equivalent of the P1 promoter does not appear to exist in Salmonella typhimurium. We demonstrate in this study that wild-type S. typhimurium has a cryptic P1 promoter that is recognized by sigmaS RNA polymerase in vitro and that a 22-bp deletion from +63 to +84 (relative to the start site of transc...

  9. Enhancement of Th1-biased protective immunity against avian influenza H9N2 virus via oral co-administration of attenuated Salmonella enterica serovar Typhimurium expressing chicken interferon-α and interleukin-18 along with an inactivated vaccine

    Directory of Open Access Journals (Sweden)

    Rahman Md

    2012-07-01

    Full Text Available Abstract Background Control of currently circulating re-assorted low-pathogenicity avian influenza (LPAI H9N2 is a major concern for both animal and human health. Thus, an improved LPAI H9N2 vaccination strategy is needed to induce complete immunity in chickens against LPAI H9N2 virus strains. Cytokines play a crucial role in mounting both the type and extent of an immune response generated following infection with a pathogen or after vaccination. To improve the efficacy of inactivated LPAI H9N2 vaccine, attenuated Salmonella enterica serovar Typhimurium was used for oral co-administration of chicken interferon-α (chIFN-α and chicken interleukin-18 (chIL-18 as natural immunomodulators. Results Oral co-administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18, prior to vaccination with inactivated AI H9N2 vaccine, modulated the immune response of chickens against the vaccine antigen through enhanced humoral and Th1-biased cell-mediated immunity, compared to chickens that received single administration of S. enterica serovar Typhimurium expressing either chIFN-α or chIL-18. To further test the protective efficacy of this improved vaccination regimen, immunized chickens were intra-tracheally challenged with a high dose of LPAI H9N2 virus. Combined administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18 showed markedly enhanced protection compared to single administration of the construct, as determined by mortality, clinical severity, and feed and water intake. This enhancement of protective immunity was further confirmed by reduced rectal shedding and replication of AIV H9N2 in different tissues of challenged chickens. Conclusions Our results indicate the value of combined administration of chIFN-α and chIL-18 using a Salmonella vaccine strain to generate an effective immunization strategy in chickens against LPAI H9N2.

  10. Oral Typhoid Vaccination With Live-Attenuated Salmonella Typhi Strain Ty21a Generates Ty21a-Responsive and Heterologous Influenza Virus–Responsive CD4+ and CD8+ T Cells at the Human Intestinal Mucosa

    Science.gov (United States)

    Pennington, Shaun H.; Thompson, Ameeka L.; Wright, Adam K. A.; Ferreira, Daniela M.; Jambo, Kondwani C.; Wright, Angela D.; Faragher, Brian; Gilmour, Jill W.; Gordon, Stephen B.; Gordon, Melita A.

    2016-01-01

    Background. Oral vaccination with live-attenuated Salmonella Typhi strain Ty21a is modestly efficacious, but the mechanisms of protection are currently unknown. While humoral and cellular immune responses are well described in peripheral blood, the cellular response at the intestinal mucosa has never been directly assessed. Methods. We vaccinated healthy adults with Ty21a and assessed humoral and cellular immunity in vaccinated volunteers and controls after 18 days. Immunoglobulin levels were assessed in peripheral blood by an enzyme-linked immunosorbent assay. Cellular responses were assessed in peripheral blood and at the duodenal and colonic mucosa by flow cytometry. Results. We demonstrate the generation of Ty21a-responsive and heterologous influenza virus–responsive CD4+ and CD8+ T cells at the duodenal mucosa. All duodenal responses were consistently correlated, and no responses were observed at the colonic mucosa. Peripheral anti-lipopolysaccharide immunoglobulin G and immunoglobulin A responses were significantly correlated with duodenal responses. The assessment of integrin β7 expression intensity among peripheral and duodenal T-cell subsets revealed varied capacities for mucosal homing and residence. Conclusions. The breadth of duodenal cellular responses was not reflected peripherally. The direct evaluation of mucosal immune defense may yield functional correlates of protection and could provide insight into mechanisms that may be manipulated to enhance vaccine immunogenicity. PMID:26810369

  11. 携带ePNP基因的减毒伤寒沙门菌的构建及目的基因胰腺癌细胞中的表达%Construction of attenuated Salmonella typhimurium containing PNP gene and expression in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    林勇; 刘强; 陈卫昌

    2012-01-01

    Objective To develop attenuated Salmonella typhimurium SL3261 harboring recombi-nant expressing vector of pEGFP-Cl-PNP and to detect the expression in pancreatic cancer cells. Methods PNP gene was amplified by PCR cloned into a recombinant eukaryotic expressing plasmid pEGFP-Cl-ePNP and then identified by enzyme digesting,PCR,and sequencing analysis. pEGFP-Cl-PNP vector was electrotransfered to attenuated Salmonella typhimurium SL3261. Then the stability of the morphology and suface antigen of attenuated Salmonella typhimunium containing plasmid were detected. Meanwhile the reconstructed SL3261 was cocultured with BxPc-3 cells to detect their invasion. Fluorescent microscope observasion and RT-PCR was applied to observe GFP and PNP mRNA in the host cells. Results It was proved that PNP gene segments were inserted into pEGFP-Cl correctly and transferred into attenuated Salmonella typhimunium successfully. Conclusion Attenuated Salmonella typhimunium SL3261 containing recombined eukaryotic expressing plasmid pEGFP-Cl-PNP was successfully established and correctly expressed in pancreatic cancer cells.%目的 构建含有pEGFP-C1-PNP质粒的减毒鼠伤寒沙门菌SL3261菌株,检测其在胰腺癌细胞BxPc-3中的表达.方法 PCR扩增得到PNP基因,构建真核表达载体pEGFP-C1-PNP,并进行酶切、PCR和测序鉴定.利用电转化法将重组质粒转入减毒鼠伤寒沙门菌SL3261,进行形态学和表面抗原稳定性检测.含质粒SL3261菌株与BxPc-3细胞体外共培养,利用荧光显微镜观察和RT-PCR检测绿色荧光蛋白的表达和PNP基因的转录.结果 目的基因正确连接pEGFP-C1中,并成功转入减毒鼠伤寒沙门菌,感染细胞亦检测到目的基因的表达.结论 成功构建了能携带ePNP基因真核表达质粒的SL3261菌株,且该基因能在胰腺癌细胞中正确表达.

  12. Vaccination with attenuated Salmonella enterica Dublin expressing E coli O157:H7 outer membrane protein Intimin induces transient reduction of fecal shedding of E coli O157:H7 in cattle

    Directory of Open Access Journals (Sweden)

    Fang Ferric C

    2010-07-01

    Full Text Available Abstract Background Escherichia coli serogroup O157:H7 has emerged as an important zoonotic bacterial pathogen, causing a range of symptoms from self-limiting bloody diarrhea to severe hemorrhagic colitis and hemolytic-uremic syndrome in humans. Beef and dairy cattle are considered the most important animal reservoirs for this pathogen. One of the important virulence characteristics of E. coli O157:H7 is the eaeA gene encoding the 97 kDa surface protein intimin. Intimin is required for attachment and effacement during the interaction of enterohemorrhagic E. coli with human and bovine neonatal enterocytes. The present study was undertaken to test the hypothesis that an adaptive mucosal immune response directed against intimin will reduce or prevent enteric colonization and fecal shedding of E. coli O157:H7 in cattle. Results Cattle were orally inoculated with either milk (control, milk with live attenuated Salmonella enterica serovar Dublin (vector, or milk with live attenuated recombinant S. Dublin expressing intimin (vaccinated on days 0, 14 and 28. On day 98, all calves were challenged orally with E. coli O157:H7 to evaluate whether vaccination with the recombinant S. Dublin expressing intimin would reduce the level of E. coli O157:H7 fecal shedding. During the first 28 days, vaccinated calves shed both the vector strain and the intimin-expressing S. Dublin strain at a similar level. The vector strain was shed for a significantly longer period as compared to the level of recombinant vaccine strain. Calves that received the intimin-expressed vaccine ceased shedding S. Dublin from day 28 to day 63. All calves were challenged with E. coli O157:H7 on day 98 to determine the effect on fecal shedding of E. coli O157:H7. The amount of E. coli O157:H7 in feces was measured for 30 days post-challenge. We observed a transient clearance of E. coli O157:H7 from the feces in the vaccinated calves. The magnitude of fecal E. coli O157:H7 shedding did not

  13. Experimental infection of commercial layers with wild or attenuated Salmonella Gallinarum mutant strains: anatomic pathology, total blood cell count and serum protein levels

    Directory of Open Access Journals (Sweden)

    KO Garcia

    2013-06-01

    Full Text Available The aim of the present study was to comparatively evaluate hemogram, blood serum components and anatomopathologic alterations in commercial layers experimentally challenged with an attenuated vaccine candidate strain (SG∆cobS∆cbiA and other two pathogenic strains (SGDcobS and SGNalr of Gallinarum (SG. In total, 280 commercial layers were randomly divided into 4 groups (G1, G2, G3 and G4. At five days of age, birds from groups G1 received approximately 107 colony forming units (CFU of SGDcobS; meanwhile birds from group G2 and G3 received the same dose of SGNalr and SG∆cobS∆cbiA, respectively. Birds from G4 were not infected. At 24 hours before (DBI and 24 hours after (1 DAI, and three (3 DAI, five (5 DAI, seven (7 DAI ten (10 DAI, and fifteen (15 DAI days after the infection, 10 birds of each group were humanely killed and blood samples collected to hematological and serum tests. Samples of liver, spleen, thymus, bursa of Fabricius, kidney and heart were also collected for the histological examination. Birds inoculated with SGDcobS and SGNalr showed similar alterations in hemogram, blood serum components and anatomopathologic exams. On the other hand, the exams of birds inoculated with SG∆cobS∆cbiA strain were similar to those of the uninfected birds. However, changes could be noticed in levels of uric acid and cholesterol during the course of the infection of birds from G3. Decrease in levels of light IgG 3 DAI was also observed in birds from this group. Pyknosis in kidney cells was a microscopic alteration found in birds from G3. Further studies must be done to verify if these alterations will not interfere in the performance of the vaccinate birds with SG∆cobS∆cbiA strain.

  14. Salmonella Diagnosis and Treatment

    Science.gov (United States)

    ... Salmonella Reading and Salmonella Abony Infections linked to Alfalfa Sprouts Advice to Consumers & Retailers Case Count Maps ... Signs & Symptoms Key Resources Salmonella Infections Linked to Alfalfa Sprouts from One Contaminated Seed Lot Advice to ...

  15. Reptiles, Amphibians, and Salmonella

    Science.gov (United States)

    ... What's this? Submit Button Past Emails CDC Features Reptiles, Amphibians, and Salmonella Language: English Español (Spanish) Recommend ... live. How do people get Salmonella infections from reptiles and amphibians? Reptiles and amphibians might have Salmonella ...

  16. Construction and immunogenicity of attenuated Salmonella choleraesuis C500 harbouring Japanese encephalitis virus DNA vaccine%携带猪乙型脑炎DNA疫苗减毒沙门菌的构建及其免疫原性

    Institute of Scientific and Technical Information of China (English)

    李云云; 郭万柱; 徐志文; 韩国全; 林华; 漆信桥

    2011-01-01

    In tandem with major antigenic segment of E gene were cloned into eukaryotic expression vector pCI-neo, then the recombinant plasmid named pCI-EAB was obtained. The recombinant plasmid pCI-Eab was transformed into Vero cell and the expression of recombinant plasmid was identified by RT-PCR and indirect immunofluorscence assay. Then pCI-EAB was electroporated into the attenuated Salmonella choleraesuis C500 and designated as S. C500/ pCI-Eab- Its security,stability and immunogenicity were observed. The animal experiments showed that the recombinant bacterium was relatively safe and stables the recombinant bacterium S. C500/pCI-Eab was cultured in vitro, D600nm around 0. 8 plasmid was relatively stable;BALB/c mice were immunized orally with S. C500/pCI-Eab harboring recombinant plasmid at the dosage of 108 and boosted one week later with the same dose, for a total of three times. The S. C500/pCI-EAB could induce significant humoral immune response in mice compared with the control (P <0. 01) at 1 week post-boosting and 1 week post-three immunization; spleen lymphocyte proliferative response showed that the recombinant bacterium reacted to ConA ,and the significant differences with the control group;flow cytometry displayed that CD3+ T,CD4+ T,CD8+ T ratio in the mice of S. C500/pCI-EAB group were significantly highei than the control group(P<0. 01). The results indicated that the attenuated Salmonella choleraesuis C500 as an oral delivery vector for DNA vaccine is of safety and stability and immunogenicity. S. C500/pCI-EAB vaccine strain could probably serve as a vaccine against Japanese encephalitis virus.%将乙型脑炎病毒E蛋白主要抗原片段基因串联,构建真核表达载体pCI-EAB.将重组质粒pCI-EAB转染Vero细胞,表达产物通过RT-PCR和间接免疫荧光试验可检测出目的基因的转录与表达.质粒pCI-EAB电转化入减毒猪霍乱沙门菌,观察重组菌的安全性、体内外的稳定性与免疫原性.动物试验表明,重组

  17. Construction and Activity of Attenuated Salmonella Strain Carrying Hepatocyte Growth Factor Gene%携带肝细胞生长因子基因的减毒沙门菌工程菌株的构建及其活性

    Institute of Scientific and Technical Information of China (English)

    杨志华; 赵曼; 哈小琴; 董芳; 张尚娣; 贾庆华

    2011-01-01

    Objective To construct an attenuated salmonella strain carrying hepatocyte growth factor (HGF) gene and determine its activity in vitro. Methods Human HGF gene was amplified from human placental cDNA library by PCR and cloned into eukaryotic expression vector pcK. The constructed recombinant plasmid pcKH was transformed to attenuated Salmonella Ty21a by electroporation. Gastric mucosal epithelial cells GES-1 were transfected with the obtained attenuated Salmonella strain carrying HGF gene and, 48 h later, determined for expression level of HGF protein in supernatant by ELISA, and analyzed for effect of HGF at various concentrations on proliferative activity of GES-1 cells by MTT method. Results The sequence of cloned human HGF gene was completely consistent with that of human HGF cDNA reported in GenBank (M60718. 1). Restriction analysis proved that recombinant plasmid pcKH was constructed correctly. Recombinant Salmonella strain carrying HGF gene was successfully constructed, which was tranfected into GES-1 cells effectively. Active HGF protein was expressed (14~16ng/6×105 cells), which stimulated the proliferation of GES-1 cells significantly {P < 0. 05). Conclusion An attenuated Salmonella strain carrying HGF gene was successfully constructed, with potential in treatment of gastrointestinal diseases in vivo.%目的 构建携带肝细胞生长因子(Hepatocyte growth factor,HGF)基因的减毒沙门菌工程菌株,并检测其体外活性.方法 从人胎盘cDNA文库中PCR扩增人HGF基因,克隆至真核表达载体pcK上,构建重组表达质粒pcKH,电穿孔法转入减毒沙门菌Ty21a中,获得携带HGF基因的减毒沙门菌工程菌株.将该菌株转染胃黏膜上皮细胞GES-1,48 h后采用ELISA方法检测上清中HGF蛋白的表达水平,MTT法检测不同浓度HGF表达产物对GES-1细胞增殖活力的影响.结果 克隆的人HGF基因序列与GenBank中登录的人HGF cDNA序列(M60718.1)完全一致;重组表达质粒pcKH经双酶切鉴

  18. 78 FR 42526 - Salmonella

    Science.gov (United States)

    2013-07-16

    ... HUMAN SERVICES Food and Drug Administration Salmonella Contamination of Dry Dog Food; Withdrawal of...) entitled ``Sec. 690.700 Salmonella Contamination of Dry Dog Food.'' This CPG is obsolete. DATES: The.... SUPPLEMENTARY INFORMATION: FDA issued the CGP entitled ``Sec. 690.700 Salmonella Contamination of Dry Dog...

  19. Employment of Salmonella in Cancer Gene Therapy.

    Science.gov (United States)

    Lee, Che-Hsin

    2016-01-01

    One of the primary limitations of cancer gene therapy is lack of selectivity of the therapeutic gene to tumor cells. Current efforts are focused on discovering and developing tumor-targeting vectors that selectively target only cancer cells but spare normal cells to improve the therapeutic index. The use of preferentially tumor-targeting bacteria as vectors is one of the innovative approaches for the treatment of cancer. This is based on the observation that some obligate or facultative-anaerobic bacteria are capable of multiplying selectively in tumors and inhibiting their growth. In this study, we exploited attenuated Salmonella as a tumoricidal agent and a vector to deliver genes for tumor-targeted gene therapy. Attenuated Salmonella, carrying a eukaryotic expression plasmid encoding an anti-angiogenic gene, was used to evaluate its' ability for tumor targeting and gene delivery in murine tumor models. We also investigated the use of a polymer to modify or shield Salmonella from the pre-existing immune response in the host in order to improve gene delivery to the tumor. These results suggest that tumor-targeted gene therapy using Salmonella carrying a therapeutic gene, which exerts tumoricidal and anti-angiogenic activities, represents a promising strategy for the treatment of tumors. PMID:26846804

  20. Salmonella Infections in Childhood.

    Science.gov (United States)

    Bula-Rudas, Fernando J; Rathore, Mobeen H; Maraqa, Nizar F

    2015-08-01

    Salmonella are gram-negative bacilli within the family Enterobacteriaceae. They are the cause of significant morbidity and mortality worldwide. Animals (pets) are an important reservoir for nontyphoidal Salmonella, whereas humans are the only natural host and reservoir for Salmonella Typhi. Salmonella infections are a major cause of gastroenteritis worldwide. They account for an estimated 2.8 billion cases of diarrheal disease each year. The transmission of Salmonella is frequently associated with the consumption of contaminated water and food of animal origin, and it is facilitated by conditions of poor hygiene. Nontyphoidal Salmonella infections have a worldwide distribution, whereas most typhoidal Salmonella infections in the United States are acquired abroad. In the United States, Salmonella is a common agent for food-borne–associated infections. Several outbreaks have been identified and are most commonly associated with agricultural products. Nontyphoidal Salmonella infection is usually characterized by a self-limited gastroenteritis in immunocompetent hosts in industrialized countries, but it may also cause invasive disease in vulnerable individuals (eg, children less than 1 year of age, immunocompromised). Antibiotic treatment is not recommended for treatment of mild to moderate gastroenteritis by nontyphoidal Salmonella in immunocompetent adults or children more than 1 year of age. Antibiotic treatment is recommended for nontyphoidal Salmonella infections in infants less than 3 months of age, because they are at higher risk for bacteremia and extraintestinal complications. Typhoid (enteric) fever and its potential complications have a significant impact on children, especially those who live in developing countries. Antibiotic treatment of typhoid fever has become challenging because of the emergence of Salmonella Typhi strains that are resistant to classically used first-line agents: ampicillin, trimethoprim-sulfamethoxazole, and chloramphenicol. The

  1. Cationic amino acid transporters and Salmonella Typhimurium ArgT collectively regulate arginine availability towards intracellular Salmonella growth.

    Directory of Open Access Journals (Sweden)

    Priyanka Das

    Full Text Available Cationic amino acid transporters (mCAT1 and mCAT2B regulate the arginine availability in macrophages. How in the infected cell a pathogen can alter the arginine metabolism of the host remains to be understood. We reveal here a novel mechanism by which Salmonella exploit mCAT1 and mCAT2B to acquire host arginine towards its own intracellular growth within antigen presenting cells. We demonstrate that Salmonella infected bone marrow derived macrophages and dendritic cells show enhanced arginine uptake and increased expression of mCAT1 and mCAT2B. We show that the mCAT1 transporter is in close proximity to Salmonella containing vacuole (SCV specifically by live intracellular Salmonella in order to access the macrophage cytosolic arginine pool. Further, Lysosome associated membrane protein 1, a marker of SCV, also was found to colocalize with mCAT1 in the Salmonella infected cell. The intra vacuolar Salmonella then acquire the host arginine via its own arginine transporter, ArgT for growth. The argT knockout strain was unable to acquire host arginine and was attenuated in growth in both macrophages and in mice model of infection. Together, these data reveal survival strategies by which virulent Salmonella adapt to the harsh conditions prevailing in the infected host cells.

  2. Bacterial Antigen Expression Is an Important Component in Inducing an Immune Response to Orally Administered Salmonella-Delivered DNA Vaccines

    OpenAIRE

    Gahan, Michelle E.; Webster, Diane E.; Wesselingh, Steven L.; Richard A. Strugnell; Yang, Ji

    2009-01-01

    Background The use of Salmonella to deliver heterologous antigens from DNA vaccines is a well-accepted extension of the success of oral Salmonella vaccines in animal models. Attenuated S. typhimurium and S. typhi strains are safe and efficacious, and their use to deliver DNA vaccines combines the advantages of both vaccine approaches, while complementing the limitations of each technology. An important aspect of the basic biology of the Salmonella/DNA vaccine platform is the relative contribu...

  3. Three new serotypes of Salmonella.

    OpenAIRE

    Sutch, K E; Blackburn, B O

    1980-01-01

    Three new Salmonella serotypes belonging to Kauffmann's subgenus I (F. Kauffmann, The Bacteriology of Enterobacteriaceae, 1966) were identified. These serotypes were Salmonella brazos 6,14,18:a:e,n,z15, Salmonella midway 6,14,24:d:1,7, and Salmonella balboa 48a, 48b:z41:monophasic.

  4. Genome Sequence of Salmonella enterica Serovar Typhi Oral Vaccine Strain Ty21a.

    Science.gov (United States)

    Xu, Deqi; Cisar, John O; Poly, Frédéric; Yang, Jinghua; Albanese, Jason; Dharmasena, Madushini; Wai, Tint; Guerry, Patricia; Kopecko, Dennis J

    2013-01-01

    Attenuated Salmonella enterica serovar Typhi strain Ty21a is an important vaccine for controlling typhoid fever and serves as an oral vector for delivering heterologous antigens. The key attenuating features of this randomly mutated strain remain in question. Genome sequencing has revealed 679 single nucleotide polymorphisms (SNPs), and will help define alterations contributing to Ty21a safety and immunogenicity. PMID:23969054

  5. Vaccines against invasive Salmonella disease: current status and future directions.

    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

  6. Preparation of Attenuated Salmonella Typhimurium Strain Containing pCMV-IL-2-IRES-NK4 Plasmid and Its Stability%含 pCMV-IL-2-IRES-NK4质粒减毒沙门菌的制备及其稳定性研究

    Institute of Scientific and Technical Information of China (English)

    杨志华; 哈小琴; 张尚弟; 冯强生; 薛荣利; 杨淑娟; 赵勇; 杨迎桂

    2014-01-01

    目的:制备含 pCMV-IL-2-IRES-NK4质粒减毒沙门菌 TPIN 并检测其稳定性。方法将 pCMV-IL-2-IRES-NK4质粒转进减毒沙门菌 Ty21a 感受态,制备成重组的减毒沙门菌菌株 TPIN;将 TPIN 在含有氨苄西林(+)和氨苄西林(-)的 LB 培养板传代培养至第10代、20代、30代和40代时用灭菌的牙签分别挑取含有氨苄西林(+)和氨苄西林(-)LB 培养基上的单克隆菌落,质粒提取、PCR 扩增酶切鉴定;TPIN 转染 HepG2细胞后采用 RT-PCR 检测IL-2和 NK4基因表达,ELISA 法检测细胞培养上清 IL-2和 NK4蛋白。结果构建菌株经提取质粒、酶切、PCR 扩增获得目的基因 IL-2、NK4特异条带;在氨苄西林(+)和氨苄西林(-)LB 培养板传代培养40代的 TPIN 菌株均可扩增并双酶切出目的基因 IL-2及 NK4;TPIN 体外转染 HepG2细胞后,IL-2及 NK4表达水平均显著升高。结论重组携带IL-2/ NK4双基因的减毒沙门菌菌株 TPIN 可稳定遗传,不受无选择性压力的影响而丢失质粒,且在体外 IL-2、NK4基因及蛋白可以稳定高效表达。%Objective To prepare an attenuated Salmonella typhimurium DNA vaccine containing pCMV-IL-2-IRES-NK4 plasmid (TPIN) and to detect its stability. Methods The pCMV-IL-2-IRES-NK4 plasmid was transformed into an attenuated Salmonella typhimurium Ty21a competence, and then a recombinant attenuated Salmonella typhimuri-um strain TPIN was prepared; the recombinant strain was cultivated in 40 generations on LB nutritional medium plate with or without Ampicillin, and monoclonal bacterial colony was selected at subculture 10th , 20th , 30th and 40th generation from Ampicillin ( + ) and no Ampicillin ( - ) plates respectively, and then the plasmids were extracted and identified by PCR amplification and enzyme digestion; TPIN was transfected into HepG2 cells, then expressions of the IL-2 / NK4 genes were determined by reverse transcription polymerase chain reaction (RT-PCR), and expressions of IL-2 / NK4

  7. Salmonella enterica Serovar Typhimurium Lacking hfq Gene Confers Protective Immunity against Murine Typhoid

    OpenAIRE

    Allam, Uday Shankar; Krishna, Gopala M; Lahiri, Amit; Joy, Omana; Chakravortty, Dipshikha

    2011-01-01

    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 generat...

  8. Phagocyte roulette in Salmonella killing.

    Science.gov (United States)

    Fenlon, Luke A; Slauch, James M

    2014-01-15

    Salmonella propagates in macrophages to cause life-threatening infections, but the role of neutrophils in combating Salmonella has been controversial. In this issue, Burton et al. (2014) use single cell analyses and modeling to explain the ability of Salmonella to survive in macrophages while being killed by neutrophils. PMID:24439894

  9. Phagocyte Roulette in Salmonella Killing

    OpenAIRE

    Fenlon, Luke A.; Slauch, James M.

    2014-01-01

    Salmonella propagate in macrophages to cause life-threatening infections, but the role of neutrophils in combating Salmonella has been controversial. In this issue, Burton et al. (2013) use single cell analyses and modeling to explain the ability of Salmonella to survive in macrophages, while being killed by neutrophils.

  10. Oral immunization of mice with attenuated Salmonella typhimu rium expressing Helicobacter pylori urease B subunit%表达幽门螺杆菌尿素酶B亚单位的减毒鼠伤寒杆菌口服疫苗的制备

    Institute of Scientific and Technical Information of China (English)

    刘晓峰; 张霞; 胡家露; 樊代明

    2002-01-01

    目的制备表达幽门螺杆菌 (H. pylori) 尿素酶B亚单位(UreB)的减毒鼠伤寒杆菌活菌重组疫苗,并观测Balb/c小鼠口服该重组疫苗后的免疫效果. 方法构建表达UreB的重组减毒鼠伤寒杆菌的疫苗株,SL3261/pTC01-UreB ,并用Western-blot检测UreB的表达.将SL3261/pTC01-UreB口服免疫Balb/c小鼠,12周后检测肠液和血清中的特异性抗体反应及脾细胞培养液上清中的IFN-γ和IL-10含量.结果 Western-blot显示减毒鼠伤寒杆菌株SL3261/ pTC01-UreB能表达约 61KD的蛋白,与H. pylori UreB亚单位蛋白分子量相符,具有抗原性.口服免疫小鼠后,疫苗组小鼠的肠液和血清中可分别检测到针对UreB的特异性IgA和IgG抗体,小鼠脾细胞培养上清中的IFN-γ和IL-10的含量亦明显升高.病理学检查显示疫苗组小鼠与对照组小鼠胃粘膜炎症指数无差异.结论表达H. pylori UreB的减毒鼠伤寒杆菌SL3261/pTC01-UreB可用作抗H. pylori感染的口服疫苗.%Objective To establish attenuated Salmonella typhimu rium producing Helicobacter pylori (H. pylori) urease subunit B (UreB) and determine whether it could be used as an oral vaccine against H. pylori.Methods H. pylori (SS1 strain) UreB gene fragment amplified by PCR was cloned into the prokaryotic expression vector pTC01 after sequencing, and then transformed into attenuated Salmonella typhimurium SL32 61 to acquire SL3261/pTC01-UreB. The expression of H. pylori UreB in SL32 61 was detected by Western blot. Twelve weeks after oral immunization of mice, antibody responses were evaluated using serum and intestinal fluid by ELISA assay. Interferon-γ (IFN-γ) and interleukin-10 (IL-10) in the supernatant of spleen cells culture were also assessed by ELISA. Invitro stability of pTC01-UreB plasmid in SL3261 was confirmed by growing in Luria Broth (LB) medi um to 80 generations. Results The UreB gene fragment amplified by PCR was co nsistent with the sequence of the H. pylori UreB as evidenced by

  11. 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...

  12. Salmonella enteritidis in Quail Eggs

    OpenAIRE

    Erdoğrul, Özlem Turgay

    2002-01-01

    The presence of Salmonella enteritidis was investigated in 123 liquid whole quail eggs. Salmonella strains were identified and sero-grouped by coagglutination test and slide agglutination test. Seven (5.69%) of 123 whole quail eggs were in group D1 and were sero-typed as Salmonella enteritidis. It was found that in phage-typing of Salmonella enteritidis, three of 7 strains were Salmonella enteritidis PT4 , two of them were PT1, one of them was PT7, and one of them was indefinite.

  13. Salmonella enteritidis in Argentina.

    Science.gov (United States)

    Caffer, M I; Eiguer, T

    1994-01-01

    A significant increase in the number of isolations of Salmonella enteritidis has been observed in Argentina since 1986. Outbreaks of foodborne diseases in humans were associated with the consumption of raw or undercooked hens' eggs. Between 1986 and the first 6 months of 1993 there were 150 outbreaks reported, affecting more than 6000 persons. A total of 71.3% of these outbreaks were confirmed by stool cultures, and 47.3% by bacteriological study of the food implicated in the outbreak. A permanent surveillance of salmonellosis is imperative, taking into account the persistence of Salmonella enteritidis isolations in sporadic cases and in new outbreaks. PMID:8155472

  14. Salmonella strain secreting active listeriolysin changes its intracellular localization.

    OpenAIRE

    Gentschev, I; Sokolovic, Z; Mollenkopf, H.J.; Hess, J; Kaufmann, S.H.; Kuhn, M; Krohne, G F; Goebel, W

    1995-01-01

    We describe the construction of an attenuated Salmonella dublin aroA strain which secretes via the Escherichia coli hemolysin secretion machinery an active hybrid cytolysin consisting of listeriolysin from Listeria monocytogenes and the C-terminal secretion signal of E. coli hemolysin. This hemolytic S. dublin strain is partially released into the cytoplasm of the host cell following uptake by J774 macrophage cells, whereas the nonhemolytic control S. dublin aroA strain remains in the phagosome.

  15. Loss of the lac operon contributes to Salmonella invasion of epithelial cells through derepression of flagellar synthesis.

    Science.gov (United States)

    Jiang, Lingyan; Ni, Zhiwei; Wang, Lei; Feng, Lu; Liu, Bin

    2015-03-01

    Salmonella, a genus that is closely related to Escherichia coli, includes many pathogens of humans and other animals. A notable feature that distinguishes Salmonella from E. coli is lactose negativity, because the lac operon is lost in most Salmonella genomes. Here, we expressed the lac operon in Salmonella enterica serovar Typhimurium and compared the virulence of the Lac(+) strain to that of the wild-type strain in a murine model, invasion assays, and macrophage replication assays. We showed that the Lac(+) strain is attenuated in vivo and the attenuation of virulence is caused by its defect in epithelial cell invasion. However, the invasion-defective phenotype is unrelated to lactose utilization. Through sequencing and the comparison of the transcriptome profile between the Lac(+) and wild-type strains during invasion, we found that most flagellar genes were markedly downregulated in the Lac(+) strain, while other genes associated with invasion, such as the majority of genes encoded in Salmonella pathogenicity island 1, were not differentially expressed. Moreover, we discovered that lacA is the major repressor of flagellar gene expression in the lac operon. In conclusion, these data demonstrate that the lac operon decreases Salmonella invasion of epithelial cells through repression of flagellar biosynthesis. As the ability to invade epithelial cells is a critical virulence determinant of Salmonella, our results provide important evidence that the loss of the lac operon contributes to the evolution of Salmonella pathogenicity. PMID:25362512

  16. Multiplex PCR for the concurrent detection and differentiation of Salmonella spp., Salmonella Typhi and Salmonella Typhimurium

    Science.gov (United States)

    Pui, Chai Fung; Wong, Woan Chwen; Chai, Lay Ching; Lee, Hai Yen; Noorlis, Ahmad; Zainazor, Tuan Chilek Tuan; Tang, John Yew Huat; Ghazali, Farinazleen Mohamad; Cheah, Yoke Kqueen; Nakaguchi, Yoshitsugu; Nishibuchi, Mitsuaki; Radu, Son

    2011-01-01

    Salmonellosis outbreaks involving typhoid fever and human gastroenteritis are important diseases in tropical countries where hygienic conditions are often not maintained. A rapid and sensitive method to detect Salmonella spp., Salmonella Typhi and Salmonella Typhimurium is needed to improve control and surveillance of typhoid fever and Salmonella gastroenteritis. Our objective was the concurrent detection and differentiation of these food-borne pathogens using a multiplex PCR. We therefore designed and optimized a multiplex PCR using three specific PCR primer pairs for the simultaneous detection of these pathogens. The concentration of each of the primer pairs, magnesium chloride concentration, and primer annealing temperature were optimized before verification of the specificity of the primer pairs. The target genes produced amplicons at 429 bp, 300 bp and 620 bp which were shown to be 100% specific to each target bacterium, Salmonella spp., Salmonella Typhi and Salmonella Typhimurium, respectively. PMID:22028607

  17. Interaction of Salmonella enterica with Fresh Produce Leaves

    Science.gov (United States)

    Attachment and colonization of Salmonella enterica serovars to fresh produce leaves was investigated. Biofilm assay and attachment of Salmonella serovars to intact and cut leaves were determined. Salmonella Tennessee and Salmonella Thompson produced stronger biofilms compared to Salmonella Newpor...

  18. Cell lines and Salmonella

    NARCIS (Netherlands)

    Jonge R de; Hendriks H; Garssen J; Universteit Utrecht, afdeling; MGB; LPI

    2001-01-01

    In human gastrointestinal disease caused by Salmonella, transepithelial migration of neutrophils follows the attachment of bacteria to epithelial tissue. This migration of neutrophils is stimulated by the release of chemokines, including interleukin-8 (Il -8), from the epithelial cells. We have dev

  19. 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. PMID:26743045

  20. Iron ERRs with Salmonella

    OpenAIRE

    Fang, Ferric C.; Weiss, Günter

    2014-01-01

    The hormone hepcidin promotes iron sequestration by macrophages. A recent study by Kim et al (2014) implicates the orphan receptor ERRγ in the regulation of hepcidin production and suggests that targeting the ERRγ-hepcidin axis may be beneficial during infection with the facultative intracellular pathogen Salmonella.

  1. 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 ...

  2. Salmonella – A Brief Summary

    OpenAIRE

    Nurmi Esko

    2002-01-01

    Abstract Salmonellosis is the main cause of human bacterial gastroenteritis in most European countries. Infections with Salmonella is usually subclinical, whereas clinical cases show symptoms with a wide range of severity. Infection is most commonly associated with the consumption of meat, especially poultry or pork, and eggs and their products. Salmonella can enter the food chain at any point throughout its length. The principal reservoir of Salmonellae is the gastrointestinal tract of mamma...

  3. Differential effect of auxotrophies on the release of macromolecules by Salmonella enterica vaccine strains.

    OpenAIRE

    Loessner, Holger; Endmann, Anne; Rohde, Manfred; Curtiss, Roy; Weiss, Siegfried

    2006-01-01

    Attenuated Salmonella enterica strains have been widely used as live carriers for vaccines and therapeutic molecules. Appropriate attenuation has been introduced into such bacteria for safety reasons and the improvement of strain properties. Here, we compared two strains that were rendered auxotroph for diaminopimelic acid or thymidine monophosphate precursors by deletion of the genes asd or thyA, respectively. Upon removal of the complementing compound from bacterial cultures, both strains q...

  4. Pancreatic Involvement in Salmonella Infection

    Directory of Open Access Journals (Sweden)

    Pezzilli R

    2003-11-01

    Full Text Available CONTEXT: Salmonella has been identified as a causative agent of acute pancreatitis. OBJECTIVE: We prospectively evaluated the frequency of acute pancreatitis, pancreatic enzyme elevation and morphological pancreatic abnormalities in patients with Salmonella infection. SUBJECTS: Thirty consecutive patients with salmonellosis (Salmonella enterica serovar Enteritidis: n=25; Salmonella enterica serovar Typhimurium: n=5 and 30 sex- and age-matched healthy subjects were studied. MAIN OUTCOME MEASURES: All subjects underwent serum amylase and lipase determination and ultrasonography. RESULTS: None of the subjects developed acute pancreatitis. Two patients (6.7% and two controls showed serum amylase activity above the upper reference limit whereas, in five patients (16.7% and one control subject (3.3%, the serum lipase activity appeared above the upper reference limit. Salmonella infection significantly increased serum activity of lipase (P less than 0.001 while it did not significantly affect serum amylase levels (P=0.204. Serum lipase activity was significantly higher in patients infected by Salmonella enterica serovar Typhimurium than in those infected by Salmonella enterica serovar Enteritidis (P=0.012. Ultrasonography did not show pancreatic abnormalities in any of the subjects. CONCLUSIONS: Our data demonstrated an elevation of serum lipase activity in gastroenteritis due to Salmonella infection, but this elevation does not seem to have clinical significance. The elevation of serum lipase seems to be particularly related to infection from Salmonella enterica serovar Typhimurium.

  5. The role of contaminated feed in the epidemiology and control of Salmonella enterica in pork production.

    Science.gov (United States)

    Davies, Peter R; Scott Hurd, H; Funk, Julie A; Fedorka-Cray, Paula J; Jones, Frank T

    2004-01-01

    Food animal producers have ethical obligations to reduce the risk of foodborne hazards in animals under their care. Contaminated feed is a recognized source of Salmonella infection of food animals and regulations to control Salmonella contamination of animal feed have existed in some countries for decades. The impact of reducing Salmonella contamination of animal feeds on the risk of human foodborne salmonellosis is difficult to assess, and is likely to vary among food animal industries. In the context of U.S. pork production, factors that may attenuate or negate the impact (on public health) of regulatory interventions to control Salmonella in commercial feed include widespread use of on-farm mixing of swine feed; incomplete decontamination of feed during processing; post-processing contamination of feed at feed mills or in transportation or on-farm storage; the multitude of nonfeed sources of Salmonella infection; an apparently high risk of post-farm infection in lairage; and post-harvest sources of contamination. A structured survey of the extent of Salmonella contamination of animal feed in the United States is necessary to enable more informed debate on the feasibility and likely efficacy of enforcing a Salmonella-negative standard for animal feeds to reduce the incidence of human salmonellosis. PMID:15992282

  6. Feverlike Temperature is a Virulence Regulatory Cue Controlling the Motility and Host Cell Entry of Typhoidal Salmonella

    OpenAIRE

    Elhadad, Dana; McClelland, Michael; Rahav, Galia; Gal-Mor, Ohad

    2014-01-01

    Human infection with typhoidal Salmonella serovars causes a febrile systemic disease, termed enteric fever. Here we establish that in response to a temperature equivalent to fever (39°C–42°C) Salmonella enterica serovars Typhi, Paratyphi A, and Sendai significantly attenuate their motility, epithelial cell invasion, and uptake by macrophages. Under these feverlike conditions, the residual epithelial cell invasion of S. Paratyphi A occurs in a type III secretion system (T3SS) 1–independent man...

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Contribution of Salmonella Enteritidis virulence factors to intestinal colonization and systemic dissemination in 1-day-old chickens.

    Science.gov (United States)

    Addwebi, Tarek M; Call, Douglas R; Shah, Devendra H

    2014-04-01

    Salmonella enterica serovar Enteritidis is one of the most common serovars associated with poultry and poultry product contamination in the United States. We previously identified 14 mutant strains of Salmonella Enteritidis phage type 4 (PT4) with significantly reduced invasiveness in human intestinal epithelial cells (Caco-2), chicken macrophages (HD-11), and chicken hepatocellular epithelial cells (LMH). These included Salmonella Enteritidis mutants with transposon insertions in 6 newly identified Salmonella Enteritidis-specific genes (pegD and SEN1393), and genes or genomic islands common to most other Salmonella serovars (SEN0803, SEN0034, SEN2278, and SEN3503) along with 8 genes previously known to contribute to enteric infection (hilA, pipA, fliH, fljB, csgB, spvR, and rfbMN). We hypothesized that Salmonella Enteritidis employs both common Salmonella enterica colonization factors and Salmonella Enteritidis-specific traits to establish infection in chickens. Four Salmonella Enteritidis mutants (SEN0034::Tn5, fliH::Tn5, SEN1393::Tn5, and spvR::Tn5) were indistinguishable from the isogenic wild-type strain when orally inoculated in 1-d-old chickens, whereas 2 mutants (CsgB::Tn5 and PegD::Tn5) were defective for intestinal colonization (P pipA::Tn5) showed significant in vivo attenuation in more than one organ (P < 0.05). Complementation studies confirmed the role of rfbN and SEN3503 during infection. This study should contribute to a better understanding of the mechanisms involved in Salmonella Enteritidis pathogenesis, and the target genes identified here could potentially serve as targets for the development of live-attenuated or subunit vaccine. PMID:24706964

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

    OpenAIRE

    Hernandez, Jorge; Lindberg, Peter; Waldenström, Jonas; Drobni, Mirva; Olsen, Björn

    2012-01-01

    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 entericaserovar Pajala to this novel Salmonella.Keywords: Salmonella; epidemiology; ecology; peregrine falcon; no...

  10. Detection of Salmonella by Surface Plasmon Resonance

    OpenAIRE

    Michael Keusgen; Peter Kämpfer; Olga Lezrich; Saikat Datta Mazumdar; Benjamin Barlen

    2007-01-01

    This study explores the possibility of simultaneous and specific detection ofSalmonella serovars by surface plasmon resonance (SPR). The Plasmonic® SPR device wasused to develop this rapid assay. The sandwich immunoassay involves the use of apolyclonal anti-Salmonella antibody to simultaneous capture multiple Salmonella serovarspresent in a sample. This is followed by specific detection of the captured serovars usingO-specific anti-Salmonella antibodies. Milk spiked with Salmonella Typhimu...

  11. Rotary antenna attenuator

    Science.gov (United States)

    Dickinson, R. M.; Hardy, J. C.

    1969-01-01

    Radio frequency attenuator, having negligible insertion loss at minimum attenuation, can be used for making precise antenna gain measurements. It is small in size compared to a rotary-vane attenuator.

  12. Phylogenetic relationships of Salmonella based on rRNA sequences

    DEFF Research Database (Denmark)

    Christensen, H.; Nordentoft, Steen; Olsen, J.E.

    1998-01-01

    To establish the phylogenetic relationships between the subspecies of Salmonella enterica (official name Salmonella choleraesuis), Salmonella bongori and related members of Enterobacteriaceae, sequence comparison of rRNA was performed by maximum-likelihood analysis. The two Salmonella species were...

  13. Construction of an attenuated Salmonella pullorum △crpC79-13 mutant and its immunogenicity in chicks%减毒鸡白痢沙门氏菌△crpC79-13株的构建及其对雏鸡的免疫活性

    Institute of Scientific and Technical Information of China (English)

    程相朝; 郁川; 廖成水; 赵战勤; 张春杰; 李银聚; 吴庭才; 李小康; 李正

    2012-01-01

    为构建鸡白痢沙门氏茵C79-13株△crp基因缺失突变株,并初步观察△crpC79-13缺失菌株作为活疫苗对雏鸡的免疫活性,将含缺失320bpcrp基因的重组自杀性质粒pREAcrp与C79—13进行接合转移,两步法筛选出无抗性标记的△crpC79-13缺失菌株;通过半数致死量测定其毒力;给4日龄雏鸡口服免疫缺失菌株,在不同时间点根据胸腺、法氏囊、脾等免疫器官发育和平均日增重、外周血淋巴细胞转化试验、Griess法NO测定及血清IgG动态观察免疫水平。结果显示△crpC79-13的毒力较C79-13降低约99.6%(LD50>5.0×10^9CFU);雏鸡接种△crpC79-13(1.0×10^9CFU/只)后不影响雏鸡生长,第14-21天体内特异性细胞和体液免疫水平达到最高。表明成功构建了减毒鸡白痢沙门氏菌△crpC79-13株,其毒力显著降低,免疫雏鸡安全,具有良好的免疫活性。%To construct an △crp mutant C79-13 strain of Salmonella pullorum and determine immunogenicity of the mutant in chicks, the recombinant suicide vector pRE△crp with 320 bp-deleted crp (cAMP receptor protein) gene was conjugated with C79-13. The unmarked crp deleted strain without resistance was selected by the two-step method introduced by the transduction of recombinant suicide plasmid. The virulence of△crpC79-13 was evaluated by median lethal dose(LD50). The immune organ index and average daily body weight gain of 4-day-old chicks immunized with △crpC79-13 were measured at different time. The proliferation activity of T-lymphocytes and NO levels of macrophages in peripheral blood were determined by MTT assay and method of Griess, respectively. The serum IgG antibody was examined by ELISA. The LDs0 test showed that the virulence of the mutant was approximately 99.6% lower than C79- 13. The weight gain of the thymus,spleen and bursa and average daily body weight gain of chicken immunized with △crpC79-13(1.0×109 CFU per

  14. Salmonella Control Programs in Denmark

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar; Hald, Tine; Wong, Danilo Lo Fo; Madsen, M.; Korsgaard, Helle; Bager, Flemming; Gerner-Smidt, P.; Mølbak, K.

    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...

  15. 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.

  16. 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

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

    OpenAIRE

    Arnold Berstad; Einar Kristoffersen; Eva Colás; Anne Marita Milde; Gunnar Nysoeter; Kari Erichsen

    2007-01-01

    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 × 109, 1 × 109, and 2 × 109CFU, each dose being test...

  18. Immunoprotectivity of Salmonella enterica serovar Enteritidis virulence protein, InvH, against Salmonella typhi

    Directory of Open Access Journals (Sweden)

    Behzad Dehghani

    2014-08-01

    Full Text Available Objective(s:Typhoid fever is a dreadful disease of a major threat to public health in developing countries. Vaccination with bacterial immunodominant components such as surface proteins may prove as a potent alternative to live attenuated vaccines. InvH, an important part of needle complex in type three secretion system (TTSS plays important role in efficient bacterial adherence and entry into epithelial cells. Materials and Methods:In this work we used a 15 kDa recombinant InvH protein of Salmonella enteric serovar Enteritidis to provoke antibody production in mouse. The mice were immunized by recombinant InvH and challenged with Salmonella typhi. Histopathology of spleen and liver were studied. Results:The immunized mice showed a significant rise of antibody after the second booster. The immunization induced protection against high doses of S. typhi. The bacterial challenge with sera showed significant protection against challenge dose of 2×109 CFU. Immunized sera reacted with          S. typhi markedly. Immunoreaction of bacterially infected sera and InvH protein was significantly higher than the control group. Bacterial loads of S. typhi in spleen was more than liver. Decreased bacterial load was evident in immunized mice after 7 days. Histological examination of the liver showed the immunized mice liver remained unaffected. Conclusion: Efficacy of the virulence protein, InvH, in inhibition of this phenomenon by active immunization was shown here. It may be concluded that InvH, as an antigen, can develop protection against S. typhi infections. InvH may be exploited in protective measures as well as a diagnostic tool in Salmonella infections.

  19. Salmonella in Sheep in Iceland

    Directory of Open Access Journals (Sweden)

    Gunnarsson E

    2002-03-01

    Full Text Available In 1995 several outbreaks of food poisoning in humans occurred in Iceland, that were traced to salmonella contamination of singed sheep heads. This prompted us to study the prevalence of salmonella infection in sheep and to trace where and how infection might have occurred. Faecal, intestinal contents and tonsillar samples were collected in the spring and autumn from sheep on 50 farms in the southwestern part of the country, where salmonellosis had been detected and from 5 farms in the northwestern part of the country. All faecal samples from the southwest were negative, whereas samples from 3 farms obtained in the autumn in the northwest were positive. Tonsillae taken in the autumn were positive in sheep from 3 farms in the southwest and 2 in the northwest. Our results show that salmonella infection is rare in Icelandic sheep but healthy carriers may harbour the bacteria in tonsillae. Salmonella was not detected in drainage from slaughterhouses nor in singed sheep heads.

  20. Construction and Identification of Attenuated Salmonella typhimurium Harbouring S/N Double Fusion Genes of Porcine Transmissible Gastroenteritis Virus%携带猪传染性胃肠炎病毒S/N融合双基因的减毒沙门氏菌的构建与鉴定

    Institute of Scientific and Technical Information of China (English)

    黄小波; 李春松; 杨恒; 曹三杰; 文心田; 廖晓丹; 张鑫淼

    2012-01-01

    旨在构建携带猪传染性胃肠炎病毒(TGEV)S/N融合双基因的减毒沙门氏菌,并鉴定该疫苗菌株的生物学特性,为开展TGEV口服免疫研究奠定材料基础.采用PCR方法从克隆质粒19T-S和19T-N中分别扩增了TGEV的S基因(含主要抗原位点,2.1kb)和N基因(1.2 kb),将S基因和N基因插入pVAX1载体,构建携带S/N融合双基因的真核表达质粒pVAX-S/N.将pVAX-S/N电转化减毒沙门氏菌SL7207,筛选获得重组菌株SL7207 (pVAX-S/N),并对重组菌株SL7207 (pVAX-S/N)的体外稳定性、目的基因在体内的转录、口服接种小鼠的安全性及在体内稳定性等特性进行了鉴定.结果表明,真核质粒pVAX-S/N构建成功,该质粒转染COS7中能表达2个目的蛋白,重组菌SL7207 (pVAX-S/N)在Kan+抗性下体外培养稳定性好,口服接种小鼠3d可从回肠组织检测到目的基因的转录,以0.5×10 9、1×10 9和2×109 CFU口服对小鼠均具有安全性,重组菌在接种小鼠的肝、脾于4周左右逐渐被机体清除.结果表明成功构建TGEV S/N双基因疫苗SL7207 (pVAX-S/N),该疫苗具有良好的稳定性与安全性等特点,为开展TGEV口服免疫研究奠定了基础.%To provide a new vaccine for oral immunization of transmissible gastroenteritis virus (TGEV) , attenuated Salmonella typhimurium harbouring S/N double fusion genes of (TGEV) was constructed and identified. The S gene fragment (2. 1 kb) and the N gene fragment (1. 2 kb) were respectively amplified from the recombinant plasmid 19T-S and 19T-N of TGEV by RT-PCR, and then the two gene fragments were successively inserted into the eukaryotic expression vector pVAXl to construction the recombinant eukaryotic expression plasmid pVAX-S/N that expressing the S-N double fusion gene. The plasmid pVAX-S/N was identified by PCR and restric-tive digestion, and then the pVAX-S/N was transfected into COS7 cells through liposome trans-fection to identify the expressions of the two target genes hy indirect

  1. Osteomielitis por salmonella

    Directory of Open Access Journals (Sweden)

    Alicia Velázquez Pérez

    2014-08-01

    Full Text Available Se presenta el caso de una paciente femenina de color blanco y dos años de edad, con diagnóstico prenatal de sicklemia, que desde edades tempranas tiene problemas de la enfermedad. Ingresó en esta ocasión por una de las complicaciones infecciosas que ocasiona este padecimiento, una osteomielitis del húmero izquierdo, aislándose el germen en el hemocultivo realizado, una salmonella. Necesitó de tratamiento enérgico y prolongado; se obtuvo un resultado satisfactorio en la evolución de la enfermedad y se sigue sistemáticamente por consulta externa en la actualidad

  2. DC attenuation meter

    Science.gov (United States)

    Hargrove, Douglas L.

    2004-09-14

    A portable, hand-held meter used to measure direct current (DC) attenuation in low impedance electrical signal cables and signal attenuators. A DC voltage is applied to the signal input of the cable and feedback to the control circuit through the signal cable and attenuators. The control circuit adjusts the applied voltage to the cable until the feedback voltage equals the reference voltage. The "units" of applied voltage required at the cable input is the system attenuation value of the cable and attenuators, which makes this meter unique. The meter may be used to calibrate data signal cables, attenuators, and cable-attenuator assemblies.

  3. 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.

  4. 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.

  5. Reveal for Salmonella test system.

    Science.gov (United States)

    Bird, C B; Miller, R L; Miller, B M

    1999-01-01

    The Reveal for Salmonella (RSS) test system is a presumptive qualitative test that detects the presence of Salmonella organisms in foods within 21 h total testing time, allowing the user to release negative products 24 h earlier than when using other rapid test kits. Foods are enriched with a proprietary resuscitation medium called Revive and then selectively enriched with either Selenite Cystine or Rappaport-Vassiliadis selective media. The enriched culture is used to inoculate the RSS detection device, which initiates a lateral flow through a reagent zone containing anti-Salmonella antibodies conjugated to colloidal gold particles that capture antigens present in the culture. The antigen-antibody complex migrates farther and is captured by an additional anti-Salmonella antibody, causing the colloidal gold to precipitate and form a visual line, indicating a positive result. A procedural control line also will form regardless of the presence of Salmonella organisms to indicate the test is working properly. Existing AOAC Official Methods for Salmonella organisms require a 48 h enrichment before testing. Hence, a food product has to be held before release, adding extra cost to the company and the consumer. The RSS test system was evaluated by quantitative spiking studies. Although AOAC encourages inclusion of naturally contaminated foods, almost all microbiological AOAC validation studies have been performed with artificially contaminated foods for absolute control over the study. The RSS test system is designed to test many food types for Salmonella organisms and has a limit of detection of 5-10 colony-forming units (cfu)/25 g with a false-negative rate of < 1% and a false-positive rate of < 5.0%. It showed an 81% overall agreement with the traditional procedure of the U.S. Department of Agriculture's Food Safety Inspection Service. PMID:10367381

  6. Molecular Typing of Salmonella paratyphi B and Salmonella paratyphi C Isolates from Clinical Samples in Iran

    OpenAIRE

    Fahimeh Baghbani-arani; Mercedeh Tajbakhsh; Atiyeh Hashemi Soltaniyeh; Bahareh Rajaei; Seyed Davar Siadat; Mohamahreza Aghasadeghi; Seyed Mehdi Sadat

    2012-01-01

    Background & Objective: Molecular typing is an important tool in surveillance and outbreak investigations of human Salmonella infections. In this study, Subtyping of Salmonella Paratyphi B and C isolates derived from Iranian patients was carried out by RAPD-PCR to assess the extent of genetic diversity of these isolates. Materials & Methods: Fourteen Salmonella isolates including 6 strains of Salmonella paratyphi B and 8 strains of Salmonella paratyphi C were characterized using RAPD-PCR. Two...

  7. Screening for Salmonella in backyard chickens.

    Science.gov (United States)

    Manning, Johanna; Gole, Vaibhav; Chousalkar, Kapil

    2015-06-15

    Salmonellosis is a significant zoonotic disease which has a considerable economic impact on the egg layer industry. There is limited information about the prevalence of Salmonella spp. in backyard chickens. The current study was conducted to determine the prevalence of Salmonella in backyard chickens, and the associated virulence of any serovars identified. Hundred and fifteen pooled samples from 30 backyard flocks in South Australia were screened. Four flocks tested positive for Salmonella spp. The overall Salmonella isolation rate in the current study was 10.4%. The estimated prevalence at individual bird level was 0.02% (95% CI 0.025-0.975). The serovars isolated were Salmonella Agona, Salmonella subsp 2 ser 21:z10:z6 (Wandsbek) and Salmonella Bovismorbificans. All Salmonella isolates tested positive for the prgH, orfL and spiC genes. The Salmonella subsp 2 ser 21:z10:z6 (Wandsbek) had the most antibiotic resistance, being resistant to ampicillin and cephalothin and having intermediate resistance to florphenicol. All of the Salmonella Agona had intermediate resistance to the ampicillin, while the Salmonella Bovismorbificans were susceptible to all antibiotics tested. With the increased interest of keeping backyard chickens, the current study highlights the zoonotic risk from Salmonella spp. associated with home flocks. PMID:25899620

  8. Salmonella Bacterial Monotherapy Reduces Autochthonous Prostate Tumor Burden in the TRAMP Mouse Model

    Science.gov (United States)

    Kazmierczak, Robert A.; Gentry, Bettina; Mumm, Tyler; Schatten, Heide; Eisenstark, Abraham

    2016-01-01

    Attenuated Salmonella typhimurium injected in the circulatory system of mammals selectively targets tumors. Using weekly intraperitoneal injections of attenuated Salmonella strain CRC2631, we tested for regression and/or inhibition of tumor development in the TRAMP prostate tumor mouse model, which utilizes SV40 early region expression for autochthonous formation of prostate tumors that progress into metastatic, poorly differentiated prostatic carcinomas in an immunocompetent murine model. Thirteen weekly intraperitoneal administrations of 105–107 CFU CRC2631 into 10 week old mice were well tolerated by the TRAMP model. Sacrifice and histological analysis of TRAMP prostates at 22 weeks indicated that Salmonella monotherapy at administrated levels decrease visible tumor size (>29%) but did not significantly inhibit previously described SV40 expression-driven TRAMP tumor progression to undifferentiated carcinomas when histologically examined. In conclusion, this work demonstrates baseline results for CRC2631 Salmonella monotherapy using the immunocompetent TRAMP prostate tumor model in preparation for study of combination therapies that resolve autochthonously generated TRAMP prostate tumors, further reduce tumor size, or inhibit prostate tumor progression. PMID:27504973

  9. Pressure surge attenuator

    Science.gov (United States)

    Christie, Alan M.; Snyder, Kurt I.

    1985-01-01

    A pressure surge attenuation system for pipes having a fluted region opposite crushable metal foam. As adapted for nuclear reactor vessels and heads, crushable metal foam is disposed to attenuate pressure surges.

  10. 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.

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

    Directory of Open Access Journals (Sweden)

    Arnold Berstad

    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 × 109, 1 × 109, and 2 × 109CFU, 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 × 109 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.

  12. Photonic Crystal Fiber Attenuator

    Institute of Scientific and Technical Information of China (English)

    Joo Beom Eom; Hokyung Kim; Jinchae Kim; Un-Chul Paek; Byeong Ha Lee

    2003-01-01

    We propose a novel fiber attenuator based on photonic crystal fibers. The difference in the modal field diameters of a conventional single mode fiber and a photonic crystal fiber was used. A variable optical attenuator was also achieved by applying macro-bending on the PCF part of the proposed attenuator

  13. 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...... deviating results were 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....

  14. A Salmonella protein that is required for resistance to antimicrobial peptides and transport of potassium.

    OpenAIRE

    Parra-Lopez, C; Lin, R; Aspedon, A; Groisman, E A

    1994-01-01

    The ability of invading pathogens to proliferate within host tissues requires the capacity to resist the killing effects of a wide variety of host defense molecules. sap mutants of the facultative intracellular parasite Salmonella typhimurium exhibit hypersensitivity to antimicrobial peptides, cannot survive within macrophages in vitro and are attenuated for mouse virulence in vivo. We conducted a molecular genetic analysis of the sapG locus and showed that it encodes a product that is 99% id...

  15. 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...

  16. Strain differences among Salmonella serotypes

    Science.gov (United States)

    Foodborne pathogens are constantly adapting to circumvent intervention strategies. The ability to detect and overcome these adaptations are critical to ensure a safe food supply. We determined genotypic and/or phenotypic differences between Salmonella recovered from broiler chicks after comingling w...

  17. 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.

  18. Salmonella Infection and Water Frogs

    Centers for Disease Control (CDC) Podcasts

    2010-01-12

    This podcast, featuring lead investigator Shauna Mettee, discusses the first known outbreak of Salmonella in people due to contact with water frogs.  Created: 1/12/2010 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 1/12/2010.

  19. ANTIMICROBIAL RESISTANCE TRENDS IN SALMONELLA

    Science.gov (United States)

    Background: Since the early 1990’s there has been increasing awareness and concern regarding the development of antimicrobial resistance among bacteria of public health significance. Reports targeting zoonotic bacteria, and in particular Salmonella species, suggest that resistance is trending upwar...

  20. Evaluation of protective efficacy of a novel inactivated Salmonella Pullorum ghost vaccine against virulent challenge in chickens.

    Science.gov (United States)

    Guo, Rongxian; Geng, Shizhong; Jiao, Hongmei; Pan, Zhiming; Chen, Xiang; Jiao, Xinan

    2016-05-01

    Salmonella Gallinarum biovar Pullorum is the causative agent of pullorum disease in poultry, an acute systemic disease that results in a high mortality rate in young chickens. Vaccines have been considered in many developing countries where levels of infection are high and eradication is not a realistic option. An attenuated strain combined with protein E-mediated cell lysis was used to generate a safety enhanced Salmonella Pullorum ghost vaccine. Immune responses and protection induced by ghost vaccine in chickens were investigated following a prime-boost immunization administered via intramuscular and oral routes. Chickens from vaccinated groups showed significant increases in antigen-specific IgG, especially after booster immunization. Lymphocyte proliferation responses were also significantly increased in all immunized groups at 2-weeks post-final vaccination. The Salmonella Pullorum ghost vaccine provided satisfactory protection against virulent Salmonella Pullorum infection, as shown by the robust stimulation of both humoral and cell-mediated immune responses as well as the reduction in the number of bacterial recovered post-challenge. Moreover, the immune effects and survival rates indicated intramuscular injection is more efficient than oral vaccination. In conclusion, our results suggest that Salmonella Pullorum ghosts may be used as a safe and effective novel inactivated vaccine candidate to protect against virulent Salmonella Pullorum infection. PMID:27090623

  1. Salmonella – A Brief Summary

    Directory of Open Access Journals (Sweden)

    Nurmi Esko

    2002-03-01

    Full Text Available Abstract Salmonellosis is the main cause of human bacterial gastroenteritis in most European countries. Infections with Salmonella is usually subclinical, whereas clinical cases show symptoms with a wide range of severity. Infection is most commonly associated with the consumption of meat, especially poultry or pork, and eggs and their products. Salmonella can enter the food chain at any point throughout its length. The principal reservoir of Salmonellae is the gastrointestinal tract of mammals and birds, but Salmonellae are able to survive and even multiply in many external environments. In Norway, Sweden and Finland cost effective prevention methods have been used for several years to prevent and control Salmonellea infections. In addition, competitive exclusion (CE and vaccination might be relevant as biological methods to prevent colonisation of bird intestines by enteropathogens, especially Salmonella. Antibiotic drug resistance has been a problem since the start of the antibiotic era. The cause for anxiety is that more and more bacteria are becoming resistant, often to a whole range of antibiotics. The debate on the use of antimicrobials in veterinary medicine and animal production dates back almost as long as the use itself. There is a clear evidence to show that antibacterial agents given to animals for growth promotion, prophylactic purposes or treatment induce a rise in the number of antibiotic resistant strains isolated from the animals. These bacteria may be transmitted to humans by several possible routes. There are thus strong arguments for preventive efforts which have to be directed towards identifying real critical control points (HACCP throughout the whole food chain, which starts from the farm and ends at the consumer's table.

  2. New Salmonella serotype: Salmonella enteritidis serotype Grandhaven (30(1):r:1,2).

    OpenAIRE

    McDougal, D L; Treleaven, B E; Renshaw, E C

    1982-01-01

    A new Salmonella serotype, Salmonella enteritidis serotype Grandhaven (30(1):r:1,2), was isolated from the stool of a 35-year-old man with mild gastroenteritis. He had just returned from Sudan, Africa.

  3. Identification of Salmonellae with the 4-methylumbelliferyl caprilate fluorescence test.

    OpenAIRE

    Olsson, M; Syk, A; Wollin, R

    1991-01-01

    We have tested 750 Salmonella strains and 130 strains of other species of the family Enterbacteriaceae with the 4-methylumbelliferyl caprilate reagent (MUCAP) test. The MUCAP test is a fluorescence test for rapid identification of Salmonella strains. The non-Salmonella strains were strains sent for identification as suspected Salmonella strains and thus have phenotypes similar to those of Salmonella strains. All 748 tested Salmonella strains of subgroups I, II, III, and IV were positive in th...

  4. Salmonella bacteriophage diversity reflects host diversity on dairy farms

    OpenAIRE

    Switt, Andrea I. Moreno; den Bakker, Henk C.; Vongkamjan, Kitiya; Hoelzer, Karin; Warnick, Lorin D.; Cummings, Kevin J.; Wiedmann, Martin

    2013-01-01

    Salmonella is an animal and human pathogen of worldwide concern. Surveillance programs indicate that the incidence of Salmonella serovars fluctuates over time. While bacteriophages are likely to play a role in driving microbial diversity, our understanding of the ecology and diversity of Salmonella phages is limited. Here we report the isolation of Salmonella phages from manure samples from 13 dairy farms with a history of Salmonella presence. Salmonella phages were isolated from 10 of the 13...

  5. Immune Reaction and Survivability of Salmonella Typhimurium and Salmonella Infantis after Infection of Primary Avian Macrophages

    OpenAIRE

    Maria Braukmann; Ulrich Methner; Angela Berndt

    2015-01-01

    Salmonella serovars are differentially able to infect chickens. The underlying causes are not yet fully understood. Aim of the present study was to elucidate the importance of Salmonella Pathogenicity Island 1 and 2 (SPI-1 and -2) for the virulence of two non-host-specific, but in-vivo differently invasive, Salmonella serovars in conjunction with the immune reaction of the host. Primary avian splenic macrophages were inoculated with Salmonella enterica sub-species enterica serovar (S.) Typhim...

  6. Control of Salmonella infections in animals and prevention of human foodborne Salmonella infections. WHO Consultation.

    OpenAIRE

    1994-01-01

    In many countries the incidence of human salmonella infections has markedly increased in recent years. To discuss recent developments and current understanding on the control of salmonella infections in animals, WHO organized a Consultation on the Control of Salmonella Infections in Animals: Prevention of Foodborne Salmonella Infections in Humans, held in Jena, Germany, on 21-26 November 1993. The present article summarizes the recommendations made by the participants on the pathoimmunogenesi...

  7. Salmonella enterica serovar Typhi live vector vaccines delivered intranasally elicit regional and systemic specific CD8+ major histocompatibility class I-restricted cytotoxic T lymphocytes.

    Science.gov (United States)

    Pasetti, Marcela F; Salerno-Gonçalves, Rosangela; Sztein, Marcelo B

    2002-08-01

    We investigated the ability of live attenuated Salmonella enterica serovar Typhi strains delivered to mice intranasally to induce specific cytotoxic T-lymphocyte (CTL) responses at regional and systemic levels. Mice immunized with two doses (28 days apart) of Salmonella serovar Typhi strain Ty21a, the licensed oral typhoid vaccine, and genetically attenuated mutants CVD 908 (DeltaaroC DeltaaroD), CVD 915 (DeltaguaBA), and CVD 908-htrA (DeltaaroC DeltaaroD DeltahtrA) induced CTL specific for Salmonella serovar Typhi-infected cells in spleens and cervical lymph nodes. CTL were detected in effector T cells that had been expanded in vitro for 7 days in the presence of Salmonella-infected syngeneic splenocytes. A second round of stimulation further enhanced the levels of specific cytotoxicity. CTL activity was observed in sorted alphabeta+ CD8+ T cells, which were remarkably increased after expansion, but not in CD4+ T cells. CTL from both cervical lymph nodes and spleens failed to recognize Salmonella-infected major histocompatibility complex (MHC)-mismatched cells, indicating that the responses were MHC restricted. Studies in which MHC blocking antibodies were used showed that H-2L(d) was the restriction element. This is the first demonstration that Salmonella serovar Typhi vaccines delivered intranasally elicit CD8+ MHC class I-restricted CTL. The results further support the usefulness of the murine intranasal model for evaluating the immunogenicity of typhoid vaccine candidates at the preclinical level. PMID:12117906

  8. 携带兔斯氏艾美耳球虫MIC-5基因减毒鼠伤寒沙门菌活疫苗的安全性、稳定性与免疫原性%Safety, stability and immunogenicity of attenuated Salmonella typhimurium carrying MIC-5 gene of Eimeria stieda

    Institute of Scientific and Technical Information of China (English)

    孟庆玲; 乔军; 才学鹏; 闫鸿斌; 田广孚; 骆学农

    2011-01-01

    对携带兔斯氏艾美耳球虫微线蛋白-5基因(MIC-5)真核表达质粒asd-pBMIC-5-IL-15的减毒鼠伤寒沙门菌X4550(X4550/asd-pBMIC-5-IL-15)进行了安全性、稳定性与免疫原性试验.结果显示,重组菌在109CFU剂量以下对家兔安全;连续培养30代重组菌,重组表达质粒可稳定存在于X4550内,具有良好的遗传稳定性;用重组菌2次免疫动物后,既能诱导机体产生抗兔斯氏艾美耳球虫抗体,也能显著增强淋巴细胞增殖水平,抗球虫指数为164.4.试验表明,减毒沙门菌介导的兔球虫调节型DNA疫苗具有良好的安全性、稳定性和免疫原性.%The security,stability and immunogenicity trials of recombinant Salmonella typhimurium X4550 carrying rabbit's Eimeria stiedai MIC-5 gene expression plasmid asd-pBMIC-5-IL-15 (X4550/asd-pBMIO5-IL-15) was assayed in this study. The results showed that the 109 CFU inoculation dose was safe in the experimental rabbits. The recombinant plasmid existed stably in X4550 after 30 passages, which displayed a good genetic stability. After two immunizations in rabbits, the recombinant Salmonella typhimurium induced the specific antibodies against rabbit Eimeria stiedai and significantly improved the level of lymphocyte proliferation. The anti-coccidia index reached 164. 4. The results indicated that the regulation DNA vaccine mediated by Salmonella had a good security,stability and immunogenicity against rabbit Eimeria stiedai.

  9. 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.

  10. Variable laser attenuator

    Science.gov (United States)

    Foltyn, Stephen R.

    1988-01-01

    The disclosure relates to low loss, high power variable attenuators comprng one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength.

  11. SPECIFIC CONTROL OF SALMONELLA IN POULTRY

    OpenAIRE

    Pimenov N.V.

    2013-01-01

    Scientifically based and clinically validated new tools and methods to combat Salmonella infection in poultry, allowing to ensure the safety and health safety products - eggs and poultry meat. The method of selective decontamination involves the use of bivalent bacteriophage that is based on highly selected phages Phagum Salmonella typhimurium and Phagum Salmonella enteritidis, as well as probiotic laktobifadola. The developed tools and methods of selective decontamination followed by immuniz...

  12. Towards a human oral vaccine for anthrax: the utility of a Salmonella Typhi Ty21a-based prime boost immunization strategy

    OpenAIRE

    Baillie, Leslie W.J.; Rodriguez, Ana L.; Moore, Stephen; Atkins, Helen S.; Feng, Chiguang; James P Nataro; Marcela F. Pasetti

    2008-01-01

    We previously demonstrated the ability of an orally administered attenuated Salmonella enterica serovar Typhimurium strain expressing the protective antigen (PA) of Bacillus anthracis to confer protection against lethal anthrax aerosol spore challenge [1]. To extend the utility of this approach to humans we constructed variants of S. enterica serovar Typhi Ty21a, an attenuated typhoid vaccine strain licensed for human use, which expressed and exported PA via two distinct plasmid-based transpo...

  13. Genetic diversity of Salmonella pathogenicity islands SPI-5 and SPI-6 in Salmonella Newport.

    Science.gov (United States)

    Cao, Guojie; Allard, Marc; Strain, Errol; Stones, Robert; Zhao, Shaohua; Brown, Eric; Meng, Jianghong

    2014-10-01

    Salmonella enterica subspecies enterica serotype Newport is one of the common serotypes causing foodborne salmonellosis outbreaks in the United States. Salmonella Newport consists of three lineages exhibiting extensive genetic diversity. Due to the importance of Salmonella pathogenicity islands 5 and 6 (SPI-5 and SPI-6) in virulence of pathogenic Salmonella, the genetic diversity of these two SPIs may relate to different potentials of Salmonella Newport pathogenicity. Most Salmonella Newport strains from North America belong to Salmonella Newport lineages II and III. A total 28 Salmonella Newport strains of lineages II and III from diverse sources and geographic locations were analyzed, and 11 additional Salmonella genomes were used as outgroup in phylogenetic analyses. SPI-5 was identified in all Salmonella Newport strains and 146 single nucleotide polymorphisms (SNPs) were detected. Thirty-nine lineage-defining SNPs were identified, including 18 nonsynonymous SNPs. Two 40-kb genomic islands (SPI5-GI1 and SPI5-GI2) encoding bacteriophage genes were found between tRNA-ser and pipA. SPI5-GI1 was only present in Salmonella Newport multidrug-resistant strains of lineage II. SPI-6 was found in all strains but three Asian strains in Salmonella Newport lineage II, whereas the three Asian strains carried genomic island SPI6-GI1 at the same locus as SPI-6 in other Salmonella. SPI-6 exhibited 937 SNPs, and phylogenetic analysis demonstrated that clustering of Salmonella Newport isolates was a reflection of their geographic origins. The sequence diversity within SPI-5 and SPI-6 suggests possible recombination events and different virulence potentials of Salmonella Newport. The SNPs could be used as biomarkers during epidemiological investigations. PMID:25188010

  14. Comparison of Salmonella enterica Serovar Typhimurium LT2 and Non-LT2 Salmonella Genomic Sequences, and Genotyping of Salmonellae by Using PCR†

    OpenAIRE

    Kim, Hyun-Joong; Park, Si-Hong; Kim, Hae-Yeong

    2006-01-01

    Genes of Salmonella enterica serovar Typhimurium LT2 expected to be specifically present in Salmonella were selected using the Basic Local Alignment Search Tool (BLAST) program. The 152 selected genes were compared with 11 genomic sequences of Salmonella serovars, including Salmonella enterica subsp. I and IIIb and Salmonella bongori (V), and were clustered into 17 groups by their comparison patterns. A total of 38 primer pairs were constructed to represent each of the 17 groups, and PCR was ...

  15. Ethanolamine utilization in Salmonella typhimurium.

    OpenAIRE

    Roof, D M; Roth, J R

    1988-01-01

    Ethanolamine can serve as the sole source of carbon and nitrogen for Salmonella typhimurium if vitamin B12 is present to serve as a cofactor. The pathway for ethanolamine utilization has been investigated in order to understand its regulation and determine whether the pathway is important to the selective forces that have maintained the ability to synthesize B12 in S. typhimurium. We isolated mutants that are defective in ethanolamine utilization (eut mutants). These mutants defined a cluster...

  16. Nontyphoidal salmonella disease: Current status of vaccine research and development.

    Science.gov (United States)

    Tennant, Sharon M; MacLennan, Calman A; Simon, Raphael; Martin, Laura B; Khan, M Imran

    2016-06-01

    Among more than 2500 nontyphoidal Salmonella enterica (NTS) serovars, S. enterica serovar Typhimurium and S. enterica serovar Enteritidis account for approximately fifty percent of all human isolates of NTS reported globally. The global incidence of NTS gastroenteritis in 2010 was estimated to be 93 million cases, approximately 80 million of which were contracted via food-borne transmission. It is estimated that 155,000 deaths resulted from NTS in 2010. NTS also causes severe, extra-intestinal, invasive bacteremia, referred to as invasive nontyphoidal Salmonella (iNTS) disease. iNTS disease usually presents as a febrile illness, frequently without gastrointestinal symptoms, in both adults and children. Symptoms of iNTS are similar to malaria, often including fever (>90%) and splenomegaly (>40%). The underlying reasons for the high rates of iNTS disease in Africa are still being elucidated. Evidence from animal and human studies supports the feasibility of developing a safe and effective vaccine against iNTS. Both antibodies and complement can kill Salmonella species in vitro. Proof-of-principle studies in animal models have demonstrated efficacy for live attenuated and subunit vaccines that target the O-antigens, flagellin proteins, and other outer membrane proteins of serovars Typhimurium and Enteritidis. More recently, a novel delivery strategy for NTS vaccines has been developed: the Generalized Modules for Membrane Antigens (GMMA) technology which presents surface polysaccharides and outer membrane proteins in their native conformation. GMMA technology is self-adjuvanting, as it delivers multiple pathogen-associated molecular pattern molecules. GMMA may be particularly relevant for low- and middle-income countries as it has the potential for high immunologic potency at a low cost and involves a relatively simple production process without the need for complex conjugation. Several vaccines for the predominant NTS serovars Typhimurium and Enteritidis, are

  17. Reiter's syndrome after salmonella infection

    Directory of Open Access Journals (Sweden)

    Čanović Predrag S.

    2004-01-01

    Full Text Available Two patients with Reiter's syndrome, after Salmonella infection were treated on the Infections disease ward at Clinical hospital center in Kragujevac. In the first patient, ten days after the onset of Salmonella infection, signs of edema and pain in the right ankle occurred, accompanied by expressed conjunctivitis. Within next two months consecutive metatarsophalanges changes joint of the right foot have appeared. In the second patient, two weeks after the onset of Salmonella infection, edema of the left hand joints and a week later edema of the right hand and right ankle joints appeared. In both patients inflammatory syndrome was expressed (high erythrocyte sedimentation rates, fibrinogen, C-reactive protein along with negative rheumatoid factors and positive antigen HLA-B27. Outcome of the disease in both cases was favorable upon receiving nonsteroid antirheumatic therapy. Signs of arthritis disappeared after three months. No signs of recurrent arthritis have been seen during the next four years in the first and next two years in the second patient.

  18. Procalcitonin levels in salmonella infection

    Directory of Open Access Journals (Sweden)

    Vikas Mishra

    2015-01-01

    Full Text Available Aim: Procalcitonin (PCT as a diagnostic marker for bacteremia and sepsis has been extensively studied. We aimed to study PCT levels in Salmonella infections whether they would serve as marker for early diagnosis in endemic areas to start empiric treatment while awaiting blood culture report. Materials and Methods: BACTEC blood culture was used to isolate Salmonella in suspected enteric fever patients. Serum PCT levels were estimated before starting treatment. Results: In 60 proven enteric fever patients, median value of serum PCT levels was 0.22 ng/ml, values ranging between 0.05 and 4 ng/ml. 95% of patients had near normal or mild increase (<0.5 ng/ml, only 5% of patients showed elevated levels. Notably, high PCT levels were found only in severe sepsis. Conclusion: PCT levels in Salmonella infections are near normal or minimally increased which differentiates it from other systemic Gram-negative infections. PCT cannot be used as a specific diagnostic marker of typhoid.

  19. Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI (2001) on typing of Salmonella

    OpenAIRE

    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 typering van Salmonella werd georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) in samenwerking met Public Health Laboratory Services (PHLS...

  20. FAKTOR VIRULENSI Salmonella enterica SEROVAR TYPHI

    Directory of Open Access Journals (Sweden)

    Marvy Khrisna Pranamartha

    2015-09-01

    Full Text Available ABSTRAK Demam tifoid disebabkan oleh bakteri Salmonella typhi, dengan gejala umum berupa demam tinggi dan nyeri perut. Tifoid adalah penyakit infeksi yang disebabkan oleh bakteri Salmonella typhi, yang masuk ke dalam tubuh melalui mulut dan saluran cerna.1 Untuk bisa memahami patogenesis dari demam tifoid sampai ke tingkat selular dan molekular, ada 5 hal penting yang harus digaris bawahi, yaitu: 1.\tTipe 3 Sistem Sekresi (T3SS 2.\tVirulence Genes dari Salmonella yang mengkode 5 SIP (Salmonella Invasion Protein SIP A, B, C, D, dan E. 3.\tToll R2 dan toll R3 yang merupakan lapisan luar dari makrofag. 4.\tSistem imun lumen usus sampai ke organ dalam 5.\tFungsi endotelial sel dalam inflamasi. Infeksi Salmonella dapat berakibat fatal kepada bayi, balita, ibu hamil dan kandungannya serta orang lanjut usia. Hal ini disebabkan karena kekebalan tubuh mereka yang menurun. Virulensi salmonella tidak lepas dari peranan SPI, yang terletak di dalam kromosom dan plasmid bakteri. Dimana SPI 1 dan SPI 2 telah dikaji cukup mendalam karena keterkaitannya dengan T3SS, dan berperan sangat penting pada invasi awal serta siklus hidup intrasel dari bakteri Salmonella. Kontaminasi Salmonella dapat dicegah dengan mencuci tangan dan menjaga kebersihan makanan yang dikonsumsi. Selalu menjaga kebersihan lingkungan hidup kita agar terhindar dari kontaminasi dengan bakteri Salmonella typhi. Agar mewaspadai sejak dini pencegahan dan pengobatan penyakit typhus. Studi mendalam perlu dilakukan agar kita mampu lebih memahami proses kompleks antara patogen dan sel inang. Mengingat dari 15 SPI yang sudah diketahui, hanya SPI 1 dan SPI 2 yang sudah dikaji secara mendalam. Kata Kunci: Salmonella, Salmonella Invasion Protein, Typhi.

  1. Survival of Salmonella Heidelberg in hummus

    Science.gov (United States)

    Salmonella Heidelberg is the fourth-most commonly reported Salmonella serotype to cause human illness. There have been several outbreaks and recalls caused by S. Heidelberg in ready to eat foods. Recently, 700 people became ill from ingesting hummus shirazi contaminated with S. Heidelberg. This stud...

  2. Neonatal Salmonella Typhi Meningitis: A Rare Entity

    OpenAIRE

    Singhal, Vikram; EK, Saleem; SM, Rajesh; Coutinho, Anita

    2012-01-01

    Salmonella meningitis is rarely seen in neonates and if it is present, it is associated with complications like subdural collections and abscesses. We are presenting a case of Salmonella meningitis in a 28 days old neonate who developed complications like extensive subdural collections and ventriculitis. The child responded well to prolonged systemic antibiotics and other supportive measures.

  3. Cephalosporin and Ciprofloxacin Resistance in Salmonella, Taiwan

    OpenAIRE

    Yan, Jing-Jou; Chiou, Chien-Shun; Lauderdale, Tsai-Ling Yang; Tsai, Shu-Huei; Wu, Jiunn-Jong

    2005-01-01

    We report the prevalence and characteristics of Salmonella strains resistant to ciprofloxacin and extended-spectrum cephalosporins in Taiwan from January to May 2004. All isolates resistant to extended-spectrum cephalosporins carried bla CMY-2, and all ciprofloxacin-resistant Salmonella enterica serotype Choleraesuis isolates were genetically related.

  4. Effects of crp deletion in Salmonella enterica serotype Gallinarum

    Directory of Open Access Journals (Sweden)

    Rubino Salvatore

    2007-05-01

    Full Text Available Abstract Background Salmonella enterica serotype Gallinarum (S. Gallinarum remains an important pathogen of poultry, especially in developing countries. There is a need to develop effective and safe vaccines. In the current study, the effect of crp deletion was investigated with respect to virulence and biochemical properties and the possible use of a deletion mutant as vaccine candidate was preliminarily tested. Methods Mutants were constructed in S. Gallinarum by P22 transduction from Salmonella Typhimurium (S. Typhimurium with deletion of the crp gene. The effect was characterized by measuring biochemical properties and by testing of invasion in a chicken loop model and by challenge of six-day-old chickens. Further, birds were immunized with the deleted strain and challenged with the wild type isolate. Results The crp deletions caused complete attenuation of S. Gallinarum. This was shown by ileal loop experiments not to be due to significantly reduced invasion. Strains with such deletions may have vaccine potential, since oral inoculatoin with S. Gallinarum Δcrp completely protected against challenge with the same dose of wild type S. Gallinarum ten days post immunization. Interestingly, the mutations did not cause the same biochemical and growth changes to the two biotypes of S. Gallinarum. All biochemical effects but not virulence could be complemented by providing an intact crp-gene from S. Typhimurium on the plasmid pSD110. Conclusion Transduction of a Tn10 disrupted crp gene from S. Typhimurium caused attenuation in S. Gallinarum and mutated strains are possible candidates for live vaccines against fowl typhoid.

  5. Genetic stability of vaccine strain Salmonella Typhi Ty21a over 25 years.

    Science.gov (United States)

    Kopecko, Dennis J; Sieber, Heike; Ures, Jose A; Fürer, Andreas; Schlup, Jacqueline; Knof, Ulrich; Collioud, Andre; Xu, Deqi; Colburn, Kevin; Dietrich, Guido

    2009-04-01

    The attenuated live bacterial vaccine strain Salmonella enterica Serovar Typhi Ty21a is the main constituent of Vivotif, the only licensed oral vaccine against typhoid fever. The strain was developed in the 1970s by chemical mutagenesis. In the course of this mutagenesis, a number of mutations were introduced into the vaccine strain. Characterisation of the vaccine strain during development as well as release of master- and working seed lots (MSL and WSL) and commercial batches is based on phenotypic assays assessing microbiological and biochemical characteristics of Ty21a. In the current study, we have analysed by DNA sequencing the specific mutations originally correlated with the attenuation of strain Ty21a. These data demonstrate the stability of these mutations for MSLs and WSLs of Ty21a produced between 1980 and 2005. Finally, we have confirmed the correlation of these genetic mutations with the expected phenotypic attenuations for the seed lots used in vaccine manufacture over 25 years. PMID:19121604

  6. 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...

  7. Detection of Salmonella spp. in oysters by PCR.

    OpenAIRE

    Bej, A K; Mahbubani, M H; Boyce, M. J.; Atlas, R M

    1994-01-01

    PCR DNA amplification of a region of the himA gene of Salmonella typhimurium specifically detected Salmonella spp. In oysters, 1 to 10 cells of Salmonella spp. were rapidly detected by the PCR following a pre-enrichment step to increase sensitivity and to ensure that detection was based on the presence of viable Salmonella spp.

  8. Non-Typhoidal Salmonella Aortitis in a transplant patient

    International Nuclear Information System (INIS)

    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)

  9. Risiko for salmonella ved økologisk griseproduktion

    OpenAIRE

    Jensen, Annette Nygaard

    2004-01-01

    Forsøg har vist at Salmonella bakterier kan overføres fra smittede økogrise til salmonella-frie grise holdt på udendørs arealer. Desuden kan salmonella bakterier overleve i foldmiljøet og under visse betingelser smitte salmonella-frie grise, som senere indsættes i folden.

  10. 9 CFR 113.123 - Salmonella Dublin Bacterin.

    Science.gov (United States)

    2010-01-01

    ... biological product containing Salmonella dublin fraction shall meet the applicable requirements in 9 CFR 113... 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...

  11. 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.

  12. Landing gear noise attenuation

    Science.gov (United States)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  13. RADIO FREQUENCY ATTENUATOR

    Science.gov (United States)

    Giordano, S.

    1963-11-12

    A high peak power level r-f attenuator that is readily and easily insertable along a coaxial cable having an inner conductor and an outer annular conductor without breaking the ends thereof is presented. Spaced first and second flares in the outer conductor face each other with a slidable cylindrical outer conductor portion therebetween. Dielectric means, such as water, contact the cable between the flares to attenuate the radio-frequency energy received thereby. The cylindrical outer conductor portion is slidable to adjust the voltage standing wave ratio to a low level, and one of the flares is slidable to adjust the attenuation level. An integral dielectric container is also provided. (AFC)

  14. Transovarian passage, visceral distribution, and pathogenicity of salmonella in snakes.

    OpenAIRE

    Chiodini, R J

    1982-01-01

    Transovarian passage of salmonella was evaluated in snakes by cesarean delivery and subsequent bacteriological examination of fetuses. In all cases, the same Salmonella serotype was isolated from the feces of gravid females and their fetuses. The visceral distribution of salmonella in normal snakes was found to involve almost all visceral organs. Of nonenteric organs examined, salmonella was recovered most often from the livers and ureters. Experimental infections with Salmonella typhimurium ...

  15. Uptake and Replication of Salmonella enterica in Acanthamoeba rhysodes

    OpenAIRE

    Tezcan-Merdol, Dilek; Ljungström, Marianne; Winiecka-Krusnell, Jadwiga; Linder, Ewert; Engstrand, Lars; Rhen, Mikael

    2004-01-01

    The ability of salmonellae to become internalized and to survive and replicate in amoebae was evaluated by using three separate serovars of Salmonella enterica and five different isolates of axenic Acanthamoeba spp. In gentamicin protection assays, Salmonella enterica serovar Dublin was internalized more efficiently than Salmonella enterica serovar Enteritidis or Salmonella enterica serovar Typhimurium in all of the amoeba isolates tested. The bacteria appeared to be most efficiently internal...

  16. Attenuator And Conditioner

    Science.gov (United States)

    Anderson, Gene R.; Armendariz, Marcelino G.; Carson, Richard F.; Bryan, Robert P.; Duckett, III, Edwin B.; Kemme, Shanalyn Adair; McCormick, Frederick B.; Peterson, David W.

    2006-04-04

    An apparatus and method of attenuating and/or conditioning optical energy for an optical transmitter, receiver or transceiver module is disclosed. An apparatus for attenuating the optical output of an optoelectronic connector including: a mounting surface; an array of optoelectronic devices having at least a first end; an array of optical elements having at least a first end; the first end of the array of optical elements optically aligned with the first end of the array of optoelectronic devices; an optical path extending from the first end of the array of optoelectronic devices and ending at a second end of the array of optical elements; and an attenuator in the optical path for attenuating the optical energy emitted from the array of optoelectronic devices. Alternatively, a conditioner may be adapted in the optical path for conditioning the optical energy emitted from the array of optoelectronic devices.

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

    OpenAIRE

    Sorenson, Brent

    2010-01-01

    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 SalpIL...

  18. Managing Salmonella in equine populations.

    Science.gov (United States)

    Burgess, Brandy A; Morley, Paul S

    2014-12-01

    Infection control is achieved through all efforts used to prevent the introduction and limit the spread of contagious pathogens within a facility or population, with the goal of eliminating sources of potentially pathogenic microorganisms and to disrupt infectious disease transmission. Congregating animals from multiple sources, as occurs at veterinary hospitals, racetracks, equestrian events, and boarding and training facilities, increases the risk for transmission of infectious diseases such as salmonella. There is a recognizable standard of practice for infection control and due effort must be given to control and prevention of infectious disease transmission within animal populations and facilities. PMID:25282320

  19. SALMATcor: microagglutination for Salmonella flagella serotyping.

    Science.gov (United States)

    Duarte Martínez, Francisco; Sánchez-Salazar, Luz Marina; Acuña-Calvo, María Teresa; Bolaños-Acuña, Hilda María; Dittel-Dittel, Isis; Campos-Chacón, Elena

    2010-08-01

    Salmonella is a complex bacterial group with more than 2400 serovars widely distributed in nature; they are considered zoonotic because they can infect a variety of animals and be transmitted to humans. Usually, they cause alimentary acquired diseases such as gastroenteritis, typhoid fever, and others that can lead to severe complications and death. Serotyping is useful to differentiate among Salmonella, because it shows an important correlation with their clinical and epidemiological patterns; consequently, it is of high value for public health, animal health, agriculture, and industry. To characterize all known Kauffmann-White Salmonella serovars, over 250 antisera are required. Due to this and to high prices antisera, many laboratories worldwide have limitations in establishing Salmonella surveillance. Therefore, we developed and validated a Salmonella flagella microagglutination test (SALMATcor) that significantly reduces laboratory requirements of antisera. SALMATcor is based on scaling down, by fivefold, the antigen:antiserum volumes actually required for the reference method: flagella standard tube agglutination technique (STAT). Antigen preparation, temperatures, and incubation periods remained as established for STAT. The SALMATcor was validated according to ISO/DIS 16140:1999 protocol, which included 1187 comparisons of flagella determinations conducted by SALMATcor and STAT, on 141 Salmonella isolates of 12 common serotypes and the use of antiserum recommended for STAT. SALMATcor concordance was excellent (Cohen's kappa index 0.9982), obtaining relative accuracy >99.9% and relative specificity >99.9%. Additionally, SALMATcor has been used by CNRB-INCIENSA since 2004 to respond to all 40 Salmonella proficiency testing strains, provided by World Health Organization-Global Salmonella Surveillance Network, obtaining 100% concordance on serovar identification. On the basis of the results achieved with SALMATcor and considering that it also significantly

  20. Occurrence of Salmonella sp in laying hens

    Directory of Open Access Journals (Sweden)

    Gama NMSQ

    2003-01-01

    Full Text Available This study was carried out to investigate the presence of Salmonella sp in flocks of white laying hens. In different farms, the transport boxes of twelve flocks were inspected at arrival for the presence of Salmonella. Four positive (A, B, L and M and one negative (I flocks were monitored at each four weeks using bacteriological examination of cecal fresh feces up to 52 weeks. Birds were also evaluated at 52 weeks, when 500 eggs were taken randomly, and at 76 weeks, after forced molt. Salmonella enterica serovar Enteritidis and S. enterica rough strain were isolated from the transport boxes of the four positive flocks (flocks A, B, L and M. Salmonella sp was not isolated from the transport boxes or from the feces after 76 weeks-old in flock I. Salmonella sp was isolated in the 1st, 11th, 34th, 42nd and 76th weeks from flock A; in the 1st, 4th, 11th and 76th weeks from flock B; in the first week and in the 17th to 52nd weeks from flock L; and in the 1st and 76th weeks from flock M. S. Enteritidis, S. enterica rough strain and Salmonella enterica serovar Infantis were isolated from the four positive flocks. Besides, Salmonella enterica serovar Javiana was isolated from flocks B and L, and Salmonella enterica serovar Mbandaka was isolated from flock L. Eggs produced by flock A and by flock L were contaminated with S. Enteritidis and S. enterica rough strain. According to these results, Salmonella-infected flocks may produce contaminated eggs.

  1. Enzyme-linked immunosorbent assay for Salmonella typhimurium in food: feasibility of 1-day Salmonella detection.

    OpenAIRE

    Lee, H. A.; Wyatt, G M; Bramham, S; Morgan, M.R.

    1990-01-01

    A microtitration plate, antibody-capture, enzyme-linked immunosorbent assay was developed for detection of Salmonella typhimurium. The assay utilizes a monoclonal detector antibody which shows no cross-reactions with non-Salmonella species and only a slight cross-reaction with one other Salmonella serotype. By using only one cultural stage (in a nonselective, chemically defined medium) prior to the enzyme-linked immunosorbent assay, low numbers of cells in food (10 cells 25 g-1) were detected...

  2. The Salmonella virulence plasmid enhances Salmonella-induced lysis of macrophages and influences inflammatory responses.

    OpenAIRE

    Guilloteau, L. A.; Wallis, T S; A.V. Gautier; Macintyre, S.; Platt, D. J.; Lax, A J

    1996-01-01

    The Salmonella dublin virulence plasmid mediates systemic infection in mice and cattle. Here, we analyze the interaction between wild-type and plasmid-cured Salmonella strains with phagocytes in vitro and in vivo. The intracellular recovery of S. dublin from murine peritoneal and bovine alveolar macrophages cultured in the presence of gentamicin in vitro was not related to virulence plasmid carriage. However, the virulence plasmid increased the lytic activity of S. dublin, Salmonella typhimur...

  3. Salmonella radicidation of poultry carcasses

    International Nuclear Information System (INIS)

    This thesis reports investigations using gamma-radiation to decontaminate poultry carcasses. The application to foods of doses of ionizing radiation sufficient to reduce the number of viable specific non-sporeforming pathogenic microorganisms so that none is detectable in the treated food by any standard method is termed radicidation. The doses used in this study were at such a level that no undesirable or unfavourable side-effects occurred. The effects of these doses were studied on salmonellae and other microorganisms present in, or associated with poultry carcasses and in liquid and on solid culture media as well. Decimal reduction (D10) values were estimated. These represent the dose (kGy) required to achieve a reduction in initial colony count from N0 to 0.1 N0. Together with the estimation of the numbers of Salmonella present per carcass the data were used to predict the effect of an ionizing radiation treatment of poultry. Data on the effect of ionizing radiation on the total microflora of poultry carcasses were also collected. (Auth.)

  4. Trauma Associated Acute Navicular Salmonella Osteomyelitis

    Directory of Open Access Journals (Sweden)

    Soner Sertan Kara

    2014-12-01

    Full Text Available Akut osteomyelit tani ve tedavide gecikme olmasi durumunda yol acabilecegi olasi sekeller ve mortalite nedeniyle tahrip edici olabilecek bir hastaliktir. Navikula nadiren tutulur ve Salmonella turleri de saglikli cocuklarda akut osteomyelite neden olabilir. Burada 4 yasinda, daha once bilinen bir immun yetmezligi, orak hucreli anemisi, hic bir gastrointestinal yakinma ya da supheli besin tuketim oykusu olmayan, ancak ayak bilegi burkulma oykusu olan ve akut navikuler Salmonella osteomiyeliti tanisi konulan bir erkek cocuk olgusu sunulmustur. Hasta cerrahi gecirmeden ve komplikasyon gelismeden iyilesmistir. Travma, altta yatan hastaligi olmayan, saglikli cocuklarda Salmonella osteomyelitini kolaylastirabilmektedir. Uygun tani ve tedavi, akut osteomiyelitin komplikasyonlarini ve gerekebilecek bir cerrahi girisimi engelleyebilir.

  5. 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...... in scattered epithelial cells and the number of positive cells increased with increasing times of exposure to Salmonella (P<0.0001). An increase in phospho-c-Jun in epithelial cells was already detectable 5 min after infection and often occurred in cells that appeared not to be invaded by the...

  6. 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.

  7. Comparison of the environmental survival characteristics of Salmonella Dublin and Salmonella Typhimurium.

    Science.gov (United States)

    Kirchner, Miranda J; Liebana, Ernesto; McLaren, Ian; Clifton-Hadley, Felicity A; Wales, Andrew D; Davies, Robert H

    2012-10-12

    To examine possible correlations in bovine Salmonella isolates between environmental survival and serovar-associated epidemiological patterns, bovine field isolates of Salmonella serovars Typhimurium and Dublin (two each) were inoculated into bovine faeces slurry and tested monthly by culture for survival during a six-month period of storage at a variable ambient temperature in a disused animal transporter. Low moisture conditions, where the slurry was dried onto wooden dowels, increased detectable survival of a low-level inoculum by up to five months, compared with wet slurry. A more modest increase of survival time was seen with storage of wet slurry under refrigeration at 4°C. Under both dry and wet conditions, the concentration of culturable Salmonella Typhimurium declined at a slower rate than did that of Salmonella Dublin. Salmonella that was naturally contaminating bovine faeces from farms with Salmonella Typhimurium did not show superior survival times compared with Salmonella Typhimurium that had been artificially inoculated into samples. The differing survival characteristics of the two serovars that was observed in environmental faeces may complement their different modes of infection in cattle. Salmonella Dublin, being a bovine host-adapted strain that establishes chronic infection in some animals, may have less need to survive for a prolonged period outside of its host than does Salmonella Typhimurium. PMID:22565008

  8. Molecular Typing of Salmonella paratyphi B and Salmonella paratyphi C Isolates from Clinical Samples in Iran

    Directory of Open Access Journals (Sweden)

    Fahimeh Baghbani-arani

    2012-06-01

    Full Text Available Background & Objective: Molecular typing is an important tool in surveillance and outbreak investigations of human Salmonella infections. In this study, Subtyping of Salmonella Paratyphi B and C isolates derived from Iranian patients was carried out by RAPD-PCR to assess the extent of genetic diversity of these isolates. Materials & Methods: Fourteen Salmonella isolates including 6 strains of Salmonella paratyphi B and 8 strains of Salmonella paratyphi C were characterized using RAPD-PCR. Two arbitrary primers, namely OPP-16 and P1254 were used for RAPD analysis and the dendrograms were constructed with NTsys 2.0 computer software. Results: Both primers showed high discriminatory power in differentiating of the related strains of Salmonella. The dendrograms constructed based on RAPD-PCR profiles (with both primers involving 14 salmonella strains revealed 4 distinct patterns, indicating that these isolates are genetically heterogeneous. Furthermore, a good correlation was not observed between the serotype and the molecular profiles obtained from RAPD data of the Salmonella isolates. Conclusion: The findings of the present study verify the usefulness of RAPD-PCR in characterizing and comparing strains of Salmonella Paratyphi B and C.

  9. Salmonella bongori provides insights into the evolution of the Salmonellae.

    Directory of Open Access Journals (Sweden)

    Maria Fookes

    2011-08-01

    Full Text Available The genus Salmonella contains two species, S. bongori and S. enterica. Compared to the well-studied S. enterica there is a marked lack of information regarding the genetic makeup and diversity of S. bongori. S. bongori has been found predominantly associated with cold-blooded animals, but it can infect humans. To define the phylogeny of this species, and compare it to S. enterica, we have sequenced 28 isolates representing most of the known diversity of S. bongori. This cross-species analysis allowed us to confidently differentiate ancestral functions from those acquired following speciation, which include both metabolic and virulence-associated capacities. We show that, although S. bongori inherited a basic set of Salmonella common virulence functions, it has subsequently elaborated on this in a different direction to S. enterica. It is an established feature of S. enterica evolution that the acquisition of the type III secretion systems (T3SS-1 and T3SS-2 has been followed by the sequential acquisition of genes encoding secreted targets, termed effectors proteins. We show that this is also true of S. bongori, which has acquired an array of novel effector proteins (sboA-L. All but two of these effectors have no significant S. enterica homologues and instead are highly similar to those found in enteropathogenic Escherichia coli (EPEC. Remarkably, SboH is found to be a chimeric effector protein, encoded by a fusion of the T3SS-1 effector gene sopA and a gene highly similar to the EPEC effector nleH from enteropathogenic E. coli. We demonstrate that representatives of these new effectors are translocated and that SboH, similarly to NleH, blocks intrinsic apoptotic pathways while being targeted to the mitochondria by the SopA part of the fusion. This work suggests that S. bongori has inherited the ancestral Salmonella virulence gene set, but has adapted by incorporating virulence determinants that resemble those employed by EPEC.

  10. Division of the Salmonella-Containing Vacuole and Depletion of Acidic Lysosomes in Salmonella-Infected Host Cells Are Novel Strategies of Salmonella enterica To Avoid Lysosomes▿

    OpenAIRE

    Eswarappa, Sandeepa M.; Negi, Vidya Devi; Chakraborty, Sangeeta; Chandrasekhar Sagar, B. K.; Chakravortty, Dipshikha

    2009-01-01

    Salmonella has evolved several strategies to counteract intracellular microbicidal agents like reactive oxygen and nitrogen species. However, it is not yet clear how Salmonella escapes lysosomal degradation. Some studies have demonstrated that Salmonella can inhibit phagolysosomal fusion, whereas other reports have shown that the Salmonella-containing vacuole (SCV) fuses/interacts with lysosomes. Here, we have addressed this issue from a different perspective by investigating if the infected ...

  11. Inactivation of Salmonella Senftenberg, Salmonella Typhimurium and Salmonella Tennessee in peanut butter by 915 MHz microwave heating.

    Science.gov (United States)

    Song, Won-Jae; Kang, Dong-Hyun

    2016-02-01

    This study evaluated the efficacy of a 915 MHz microwave with 3 different levels to inactivate 3 serovars of Salmonella in peanut butter. Peanut butter inoculated with Salmonella enterica serovar Senftenberg, S. enterica serovar Typhimurium and S. enterica serovar Tennessee were treated with a 915 MHz microwave with 2, 4 and 6 kW and acid and peroxide values and color changes were determined after 5 min of microwave heating. Salmonella populations were reduced with increasing treatment time and treatment power. Six kW 915 MHz microwave treatment for 5 min reduced these three Salmonella serovars by 3.24-4.26 log CFU/g. Four and two kW 915 MHz microwave processing for 5 min reduced these Salmonella serovars by 1.14-1.48 and 0.15-0.42 log CFU/g, respectively. Microwave treatment did not affect acid, peroxide, or color values of peanut butter. These results demonstrate that 915 MHz microwave processing can be used as a control method for reducing Salmonella in peanut butter without producing quality deterioration. PMID:26678129

  12. Radiofrequency attenuator and method

    Science.gov (United States)

    Warner, Benjamin P.; McCleskey, T. Mark; Burrell, Anthony K.; Agrawal, Anoop; Hall, Simon B.

    2009-11-10

    Radiofrequency attenuator and method. The attenuator includes a pair of transparent windows. A chamber between the windows is filled with molten salt. Preferred molten salts include quarternary ammonium cations and fluorine-containing anions such as tetrafluoroborate (BF.sub.4.sup.-), hexafluorophosphate (PF.sub.6.sup.-), hexafluoroarsenate (AsF.sub.6.sup.-), trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3 C.sup.-). Radicals or radical cations may be added to or electrochemically generated in the molten salt to enhance the RF attenuation.

  13. Acalculous cholecystitis due to Salmonella enteritidis

    Institute of Scientific and Technical Information of China (English)

    Maria Lourdes Ruiz-Rebollo; Gloria Sánchez-Antolín; Félix García-Pajares; Maria Antonia Vallecillo-Sande; Pilar Fernández-Orcajo; Rosario Velicia-Uames; Agustín Caro-Patón

    2008-01-01

    Acute acalculous cholecystitis (AAC) is defined as an acute inflammation of the gallbladder in the absence of stones. We herein report a case of a young man who developed AAC after a Salmonella enteritidis gastroin-testinal infection.

  14. A carbon nanotube immunosensor for Salmonella

    Directory of Open Access Journals (Sweden)

    Mitchell B. Lerner

    2011-12-01

    Full Text Available 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 (<1000 cfu/ml. In contrast, the carrier mobility is affected comparably by Salmonella and other bacteria types, with no sign of saturation even at much larger concentrations (108 cfu/ml.

  15. Radiosensitivity study of salmonella enteritidis in chickens

    International Nuclear Information System (INIS)

    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.). D10 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

  16. 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.

  17. High-Efficiency, Two-Step Scarless-Markerless Genome Genetic Modification in Salmonella enterica.

    Science.gov (United States)

    Geng, Shizhong; Tian, Qin; An, Shuming; Pan, Zhiming; Chen, Xiang; Jiao, Xinan

    2016-06-01

    We present a two-step method for scarless-markerless genome genetic modification in Salmonella enterica based on the improved suicide plasmid pGMB152. The whole LacZYA gene can provide a lacZ-based blue/white screening strategy for fast selection of double-crossover mutants by allelic exchange. The high efficiency of this genetic engineering strategy permits the study of gene function by gene knockin, site-directed mutagenesis, and gene knockout to construct live attenuated vaccines. PMID:26883127

  18. Long term prognosis of reactive salmonella arthritis

    OpenAIRE

    Leirisalo-Repo, M; Helenius, P; Hannu, T; Lehtinen, A; Kreula, J; Taavitsainen, M; Koskimies, S

    1997-01-01

    OBJECTIVES—Reactive joint complications triggered by salmonella gastroenteritis are increasingly reported, but the outcome and long term prognosis of the patients is incompletely known. This study looked at the prognosis of salmonella arthritis in patients hospitalised in 1970-1986.
METHODS—Hospital records from two hospitals in southern Finland were screened for patients with the discharge diagnosis of salmonellosis or reactive, postinfectious arthritis or Reiter's disease. For the patients ...

  19. 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. PMID:25719872

  20. Salmonella typhimurium abscess of the chest wall

    OpenAIRE

    Tonziello, Gilda; Valentinotti, Romina; Arbore, Enrico; Cassetti, Paolo; Luzzati, Roberto

    2013-01-01

    Patient: Male, 73 Final Diagnosis: Salmonella typhimurium abscess of the chest wall Symptoms: — Medication: Ciprofloxacin Clinical Procedure:— Specialty: Infectious Diseases Objective: Unusual clinical course Background: Non-typhoid Salmonella extra-intestinal infections usually develop in infants and in adult patients with pre-existing predisposing conditions. Blood stream infections and urinary tract infections are the most common clinical presentations, but other sites of infection may be ...

  1. Salmonella dublin Septicemia in Two Puppies

    OpenAIRE

    Nation, P. N.

    1984-01-01

    Two eight week old purebred female Bull Terrier puppies died within 24 hours of each other as a result of a septicemia caused by Salmonella dublin. The salient clinical features were: temperature of 41°C; rapid breathing; fluid, blood-stained stools; prostration and death. Pathological findings included embolic pneumonia, splenitis, myocarditis, nephritis and meningoencephalitis. Salmonella dublin was isolated from the spleen, lung and kidneys of both puppies.

  2. Deciphering Interplay between Salmonella Invasion Effectors

    OpenAIRE

    Cain, R. J.; Hayward, R D; Koronakis, V.

    2008-01-01

    Author Summary Critical to the onset of Salmonella infection is the ability of bacteria to force their own entry (‘invade’) into intestinal cells of their mammalian host from where they replicate, spread and cause damage. To achieve this invasion, Salmonella deliver a cocktail of proteins directly into host target cells. These proteins override host cell communications and remodel cell structure, tricking the normally dormant cells into engulfing the invaders. Although we are beginning to und...

  3. Salmonellae and salmonellosis in captive reptiles.

    OpenAIRE

    Onderka, D K; Finlayson, M. C.

    1985-01-01

    In a survey of 150 pet reptiles submitted for necropsy, 51% of snakes, 48% of lizards and 7% of turtles were infected with Salmonella. About one third of the positive animals had died due to various manifestations of salmonellosis. Thirty-one Salmonella serotypes were identified including three isolates new to Canada. The public health implications are discussed in view of the restricted popularity of reptiles and their possible infection from domestic agricultural products.

  4. Toename Salmonella en Campylobacter bij slacht : Campylobacter in pluimveesector constant, Salmonella sterk gedaald

    NARCIS (Netherlands)

    Fels-Klerx, van der H.J.; Asselt, van E.D.

    2009-01-01

    In vrijwel alle schakels van de pluimveevleesketen is de besmetting met Salmonella in de periode van 2002 tot 2005 gedaald. Campylobacter werd in diezelfde periode juist vaker in slachthuizen aangetroffen. Tijdens het slachten nam de besmetting met beide pathogenen toe, voor Salmonella gold dit voor

  5. Pressure surge attenuator

    International Nuclear Information System (INIS)

    A pressure surge attenuation arrangement comprises crushable metal foam disposed adjacent regions adapted to be expanded by a pressure surge. In a pipe system such region consists of a thin walled inner pipe surrounded by a housing with crushable metal foam disposed in the space between the housing and the inner pipe. (author)

  6. Tritium Attenuation by Distillation

    International Nuclear Information System (INIS)

    The objective of this study was to determine how a 100 Area distillation system could be used to reduce to a satisfactory low value the tritium content of the dilute moderator produced in the 100 Area stills, and whether such a tritium attenuator would have sufficient capacity to process all this material before it is sent to the 400 Area for reprocessing

  7. Natural attenuation of herbicides

    DEFF Research Database (Denmark)

    Tuxen, Nina; Højberg, Anker Lajer; Broholm, Mette Martina;

    2002-01-01

    A field injection experiment in a sandy, aerobic aquifer showed that two phenoxy acids MCPP (mecoprop) and dichlorprop were degraded within I in downgradient of the injection wells after an apparent lag period. The plume development and microbial measurements indicated that microbial growth gover...... observations may be important for application of natural attenuation as a remedy in field scale systems....

  8. Enjoying Homemade Ice Cream without the Risk of Salmonella Infection

    Science.gov (United States)

    ... Contaminants Buy, Store & Serve Safe Food Enjoying Homemade Ice Cream without the Risk of Salmonella Infection Share Tweet ... it Email Print August 2004 Every year homemade ice cream causes several outbreaks of Salmonella infection with up ...

  9. Tips to Reduce Your Risk of Salmonella from Eggs

    Science.gov (United States)

    ... CDC Features Tips to Reduce Your Risk of Salmonella from Eggs Recommend on Facebook Tweet Share Compartir ... can take to reduce my risk of a Salmonella infection from eggs? Like other foods, keep eggs ...

  10. Salmonella Is a Sneaky Germ: Seven Tips for Safer Eating

    Science.gov (United States)

    ... What's this? Submit Button Past Emails CDC Features Salmonella is a Sneaky Germ: Seven Tips for Safer Eating Recommend on Facebook Tweet Share Compartir Salmonella can contaminate more than poultry and eggs. It ...

  11. Comparative Virulotyping of Salmonella typhi and Salmonella enteritidis.

    Science.gov (United States)

    Elemfareji, Omar Ismail; Thong, Kwai Lin

    2013-12-01

    Members of Salmonella enterica are important foodborne pathogens of significant public health concern worldwide. This study aimed to determine a range of virulence genes among typhoidal (S. typhi) and non-typhoidal (S. enteritidis) strains isolated from different geographical regions and different years. A total of 87 S. typhi and 94 S. enteritidis strains were tested for presence of 22 virulence genes by employing multiplex PCR and the genetic relatedness of these strains was further characterized by REP-PCR. In S. typhi, invA, prgH, sifA, spiC, sopB, iroN, sitC, misL, pipD, cdtB, and orfL were present in all the strains, while sopE, agfC, agfA, sefC, mgtC, and sefD were present in 98.8, 97.7, 90.8, 87.4, 87.4 and 17.2 %, of the strains, respectively. No lpfA, lpfC, pefA, spvB, or spvC was detected. Meanwhile, in S. enteritidis, 15 genes, agfA, agfC, invA, lpfA, lpfC, sefD, prgH, spiC, sopB, sopE, iroN, sitC, misL, pipD, and orfL were found in all S. enteritidis strains 100 %, followed by sifA and spvC 98.9 %, pefA, spvB and mgtC 97.8 %, and sefC 90.4 %. cdtB was absent from all S. enteritidis strains tested. REP-PCR subtyped S. typhi strains into 18 REP-types and concurred with the virulotyping results in grouping the strains, while in S. enteritidis, REP-PCR subtyped the strains into eight profiles and they were poorly distinguishable between human and animal origins. The study showed that S. typhi and S. enteritidis contain a range of virulence factors associated with pathogenesis. Virulotyping is a rapid screening method to identify and profile virulence genes in Salmonella strains, and improve an understanding of potential risk for human and animal infections. PMID:24426144

  12. Cellular requirements for systemic control of Salmonella enterica serovar Typhimurium infections in mice.

    Science.gov (United States)

    Kupz, Andreas; Bedoui, Sammy; Strugnell, Richard A

    2014-12-01

    The rational design of vaccines requires an understanding of the contributions of individual immune cell subsets to immunity. With this understanding, targeted vaccine delivery approaches and adjuvants can be developed to maximize vaccine efficiency and to minimize side effects (S. H. E. Kaufmann et al., Immunity 33:555-577, 2010; T. Ben-Yedidia and R. Arnon, Hum. Vaccines 1:95-101, 2005). We have addressed the contributions of different immune cell subsets and their ability to contribute to the control and clearance of the facultative intracellular pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) in a murine model. Using a systematic and reproducible model of experimental attenuated S. Typhimurium infection, we show that distinct lymphocyte deficiencies lead to one of four different infection outcomes: clearance, chronic infection, early death, or late death. Our study demonstrates a high level of functional redundancy in the ability of different lymphocyte subsets to provide interferon gamma (IFN-γ), a critical cytokine in Salmonella immunity. Whereas early control of the infection was entirely dependent on IFN-γ but not on any particular lymphocyte subset, clearance of the infection critically required CD4(+) T cells but appeared to be independent of IFN-γ. These data reinforce the idea of a bimodal immune response against Salmonella: an early T cell-independent but IFN-γ-dependent phase and a late T cell-dependent phase that may be IFN-γ independent. PMID:25225248

  13. A compact rotary vane attenuator

    Science.gov (United States)

    Nixon, D. L.; Otosh, T. Y.; Stelzried, C. T.

    1969-01-01

    Rotary vane attenuator, when used as a front end attenuator, introduces an insertion loss that is proportional to the angle of rotation. New technique allows the construction of a shortened compact unit suitable for most installations.

  14. Photon attenuation by intensifying screens

    International Nuclear Information System (INIS)

    The photon attenuation by intensifying screens of different chemical composition has been determined. The attenuation of photons between 20 keV and 120 keV was measured by use of a multi-channel analyzer and a broad bremsstrahlung distribution. The attenuation by the intensifying screens was hereby determined simultaneously at many different monoenergetic photon energies. Experimentally determined attenuations were found to agree well with attenuation calculated from mass attenuation coefficients. The attenuation by the screens was also determined at various bremsstrahlung distributions, simulating those occurring behind the patient in various diagnostic X-ray examinations. The high attenuation in some of the intensifying screens form the basis for an analysis of the construction of asymmetric screen pairs. Single screen systems are suggested as a favourable alternative to thick screen pair systems. (Author)

  15. Conservation of Salmonella infection mechanisms in plants and animals

    OpenAIRE

    Schikora, Adam; Virlogeux-Payant, Isabelle; Bueso, Edouardo; Garcia, Anna Victoria; Nilau, Theodora; Charrier, Amélie; Pelletier, Sandra; Menanteau, Pierrette; Baccarini, Manuela; Velge, Philippe; Hirt, Heribert

    2011-01-01

    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...

  16. Early interactions of non-typhoidal Salmonella with human epithelium

    OpenAIRE

    Fang, S. -B

    2011-01-01

    Non-typhoidal Salmonella is an important bacterial pathogen causing worldwide morbidity and mortality. Early interactions between Salmonella Typhimurium and intestinal epithelium have been demonstrated in animal models, but little is known in humans. The aims of this thesis were to a) establish in vitro and ex vivo models to study such interactions, b) seek evidence of Salmonella invasion in human tissues in vivo, and c) identify virulence genes responsible for Salmonella adher...

  17. Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI (2001) on typing of Salmonella

    OpenAIRE

    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 study for Salmonella was organised by the Community Reference Laboratory for Salmonella (CRL-Salmonella, Bilthoven, The Netherlands) in collaboration with the Public Health Laboratory Services (PHLS), ...

  18. Salmonella enteritidis from a case of fever with thrombocytopenia

    Institute of Scientific and Technical Information of China (English)

    Shamma Arora; Naveen Gupta; Ashwani Kumar; IR Kaur

    2011-01-01

    Non typhoidalSalmonella species are thought to be potentially infectious to humans. We isolated Salmonella enteritidis from a 10-year-old boy with fever and thrombocytopenia. We reviewed the literature concerning infections caused bySalmonella but we could not find any such case report from India.

  19. Salmonella surrogate reduction using industrial peanut dry roasting parameters

    Science.gov (United States)

    Studies were conducted to evaluate the effectiveness of industrial peanut dry roasting parameters in Salmonella reduction using a Salmonella surrogate, Enterococcus faecium, which is slightly more heat tolerant than Salmonella. Runner-type peanuts were inoculated with E. faecium and roasted in a lab...

  20. 21 CFR 866.3550 - Salmonella spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Salmonella spp. serological reagents. 866.3550... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3550 Salmonella spp. serological reagents. (a) Identification. Salmonella spp. serological reagents are devices...

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

    International Nuclear Information System (INIS)

    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

  2. 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...

  3. 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 gulls...

  4. 76 FR 16425 - Draft Guidance for Industry: Testing for Salmonella

    Science.gov (United States)

    2011-03-23

    ... for industry entitled ``Testing for Salmonella Species in Human Foods and Direct- Human-Contact Animal... testing procedures for Salmonella spp. in human foods (except shell eggs) and direct-human- contact animal... HUMAN SERVICES Food and Drug Administration Draft Guidance for Industry: Testing for Salmonella...

  5. Feverlike Temperature is a Virulence Regulatory Cue Controlling the Motility and Host Cell Entry of Typhoidal Salmonella.

    Science.gov (United States)

    Elhadad, Dana; McClelland, Michael; Rahav, Galia; Gal-Mor, Ohad

    2015-07-01

    Human infection with typhoidal Salmonella serovars causes a febrile systemic disease, termed enteric fever. Here we establish that in response to a temperature equivalent to fever (39 °C-42 °C) Salmonella enterica serovars Typhi, Paratyphi A, and Sendai significantly attenuate their motility, epithelial cell invasion, and uptake by macrophages. Under these feverlike conditions, the residual epithelial cell invasion of S. Paratyphi A occurs in a type III secretion system (T3SS) 1-independent manner and results in restrained disruption of epithelium integrity. The impaired motility and invasion are associated with down-regulation of T3SS-1 genes and class II and III (but not I) of the flagella-chemotaxis regulon. In contrast, we demonstrate up-regulation of particular Salmonella pathogenicity island 2 genes (especially spiC) and increased intraepithelial growth in a T3SS-2-dependent manner. These results indicate that elevated physiological temperature is a novel cue controlling virulence phenotypes in typhoidal serovars, which is likely to play a role in the distinct clinical manifestations elicited by typhoidal and nontyphoidal salmonellae. PMID:25492917

  6. Downhole pressure attenuation apparatus

    International Nuclear Information System (INIS)

    This patent describes a process for preventing damage to tool strings and other downhole equipment in a well caused by pressures produced during detonation of one or more downhole explosive devices. It comprises adding to a tool string at least one pressure attenuating apparatus for attenuating the peak pressure wave and quasi-static pressure pulse produced by the explosive devices, the pressure attenuating apparatus including an initially closed relief vent including tubing means supporting a plurality of charge port assemblies each including an explosive filled shaped charge and a prestressed disc, the shaped charges interconnected by a detonating cord, the amount of explosive in each shaped charge being sufficient to rupture its associated disc without damaging surrounding tubular bodies in the well, and a vent chamber defined by the tubing means and providing a liquid free volume, and opening the relief vent substantially contemporaneously with downhole explosive device detonation by detonating the shaped charges to rupture the discs of the charge port assemblies

  7. Survival of salmonellae during pepperoni manufacture.

    Science.gov (United States)

    Smith, J L; Huhtanen, C N; Kissinger, J C; Palumbo, S A

    1975-11-01

    Survival of salmonellae in artificially contaminated beef-pork mixtures (approximately 10(4) salmonellae/g) was studied in pepperoni prepared by either a natural flora or lactic starter culture fermentation or in nonfermented sausages. The pepperoni did not become salmonellae free during the usual commercial 15 to 30-day drying period. Salmonella dublin was present in all products, fermented or unfermented, after 42 to 43 days of drying. At a lower level of contamination, 10(3)/g, S. dublin could not be recovered from starter culture-fermented pepperoni after 14 days of drying but persisted in the natural flora-fermented sausage. S. typhimurium (initial count, 10(4)/g) was absent after 42 days of drying when starter culture was used to ferment the pepperoni, but was still present in the natural flora-fermented and unfermented products. S. dublin, host adapted to cattle, or S. choleraesuis, host adapted to swine, had similar survival patterns in beef pork, or beef-pork pepperoni. Heating salmonellae contaminated beef-pork pepperoni (after fermantation but before drying) to an internal temperature of 60 C (trichinae inactivating) eliminated the food-borne pathogen from the sausage product. PMID:951

  8. 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.

  9. Salmonella and eggs: from production to plate.

    Science.gov (United States)

    Whiley, Harriet; Ross, Kirstin

    2015-03-01

    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. 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...

  11. Control algorithms for dynamic attenuators

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Scott S., E-mail: sshsieh@stanford.edu [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Pelc, Norbert J. [Department of Radiology, Stanford University, Stanford California 94305 and Department of Bioengineering, Stanford University, Stanford, California 94305 (United States)

    2014-06-15

    Purpose: The authors describe algorithms to control dynamic attenuators in CT and compare their performance using simulated scans. Dynamic attenuators are prepatient beam shaping filters that modulate the distribution of x-ray fluence incident on the patient on a view-by-view basis. These attenuators can reduce dose while improving key image quality metrics such as peak or mean variance. In each view, the attenuator presents several degrees of freedom which may be individually adjusted. The total number of degrees of freedom across all views is very large, making many optimization techniques impractical. The authors develop a theory for optimally controlling these attenuators. Special attention is paid to a theoretically perfect attenuator which controls the fluence for each ray individually, but the authors also investigate and compare three other, practical attenuator designs which have been previously proposed: the piecewise-linear attenuator, the translating attenuator, and the double wedge attenuator. Methods: The authors pose and solve the optimization problems of minimizing the mean and peak variance subject to a fixed dose limit. For a perfect attenuator and mean variance minimization, this problem can be solved in simple, closed form. For other attenuator designs, the problem can be decomposed into separate problems for each view to greatly reduce the computational complexity. Peak variance minimization can be approximately solved using iterated, weighted mean variance (WMV) minimization. Also, the authors develop heuristics for the perfect and piecewise-linear attenuators which do not requirea priori knowledge of the patient anatomy. The authors compare these control algorithms on different types of dynamic attenuators using simulated raw data from forward projected DICOM files of a thorax and an abdomen. Results: The translating and double wedge attenuators reduce dose by an average of 30% relative to current techniques (bowtie filter with tube current

  12. Flexible graphene based microwave attenuators.

    Science.gov (United States)

    Byun, Kisik; Ju Park, Yong; Ahn, Jong-Hyun; Min, Byung-Wook

    2015-02-01

    We demonstrate flexible 3 dB and 6 dB microwave attenuators using multilayer graphene grown by the chemical vapor deposition method. On the basis of the characterized results of multilayer graphene and graphene-Au ohmic contacts, the graphene attenuators are designed and measured. The flexible graphene-based attenuators have 3 dB and 6 dB attenuation with a return loss of less than -15 dB at higher than 5 GHz. The devices have shown durability in a bending cycling test of 100 times. The circuit model of the attenuator based on the characterized results matches the experimental results well. PMID:25590144

  13. Flexible graphene based microwave attenuators

    International Nuclear Information System (INIS)

    We demonstrate flexible 3 dB and 6 dB microwave attenuators using multilayer graphene grown by the chemical vapor deposition method. On the basis of the characterized results of multilayer graphene and graphene–Au ohmic contacts, the graphene attenuators are designed and measured. The flexible graphene-based attenuators have 3 dB and 6 dB attenuation with a return loss of less than −15 dB at higher than 5 GHz. The devices have shown durability in a bending cycling test of 100 times. The circuit model of the attenuator based on the characterized results matches the experimental results well. (paper)

  14. 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.

  15. Salmonella enteritidis and other Salmonella in laying hens and eggs from flocks with Salmonella in their environment.

    OpenAIRE

    Poppe, C; Johnson, R. P.; Forsberg, C M; Irwin, R J

    1992-01-01

    Seven Canadian layer flocks with Salmonella enteritidis in their environment were investigated to determine the numbers of hens infected with S. enteritidis, the localization of S. enteritidis in organs of infected hens and the numbers of S. enteritidis-infected eggs produced by two affected flocks. By a microagglutination test (MAT) using S. pullorum antigens, these flocks had more seropositive hens (mean 51.9 +/- 16.9%) than two Salmonella-free flocks (mean 13.0 +/- 4.2%). Culture of tissue...

  16. Salmonella Typhimurium and Salmonella Sofia: Growth in and Persistence on Eggs under Production and Retail Conditions

    OpenAIRE

    2015-01-01

    Salmonellosis in Australia has been linked to eggs and egg products with specific serotypes associated with outbreaks. We compared attachment to and survival on egg shells and growth in eggs of two Salmonella serotypes, an egg outbreak associated Salmonella Typhimurium and a non-egg-associated Salmonella enterica ssp. II 1,4,12,27:b:[e,n,x] (S. Sofia). Experiments were conducted at combinations of 4, 15, 22, 37 and 42°C. No significant differences occurred between the serotypes in maximum gro...

  17. Vaccines against Infections Caused by Salmonella, Shigella, and Pathogenic Escherichia coli.

    Science.gov (United States)

    Guzman, Carlos A; Borsutzky, Stefan; Favre, Didier; Dietrich, Guido

    2004-12-01

    Infectious diseases represent one of the most common causes of death worldwide, with the enteropathogenic bacteria Salmonella and Shigella and pathogenic Escherichia coli being among the most detrimental. Currently, vaccination represents the preferred method of preventing such infections. For stimulating the adaptive immune response, immunizations are frequently based on formulations which include inactivated whole-cell vaccines, live attenuated vaccines, or subunit vaccines. These can be administered via a parenteral or mucosal route, the latter having the advantage that it most closely mimics the actual course of infection. In addition to the type of vaccine and method of application, important consideration needs to be paid to safety, efficacy, and cost, which are often major bottlenecks in the successful implementation of vaccines. In this chapter we take a limited look at the history surrounding vaccinations involving Salmonella, Shigella, and pathogenic E. coli. Salmonella infections, which can lead to typhoid fever, are becoming increasing difficult to treat with antibiotics due to multi-drug-resistant strains. At present, the parenteral Vi-based subunit vaccines and the live attenuated oral vaccine Ty21a have proven to be the vaccines of choice, with high levels of protective efficacy and limited side effects. Shigella infections are responsible for the diarrheal disease shigellosis. Various live and nonliving mucosal and parenteral vaccines have been tested, with the most promising candidates evolving around those that stimulate the production of O-antigen-specific antibodies. Pathogenic Escherichia coli infections can lead to severe diseases due to the bacterium's production of several specific toxins. Vaccines against this bacterium target its toxins, as well as surface-exposed antigens, all of which have been found to be effective as immunogens. PMID:26443352

  18. Salmonella Typhi Vertebral Osteomyelitis and Epidural Abscess

    Science.gov (United States)

    Chua, Ying Ying; Chen, John L. T.

    2016-01-01

    Salmonella vertebral osteomyelitis is an uncommon complication of Salmonella infection. We report a case of a 57-year-old transgender male who presented with lower back pain for a period of one month following a fall. Physical examination only revealed tenderness over the lower back with no neurological deficits. MRI of the thoracic and lumbar spine revealed a spondylodiscitis at T10-T11 and T12-L1 and right posterior epidural collection at the T9-T10 level. He underwent decompression laminectomy with segmental instrumentation and fusion of T8 to L3 vertebrae. Intraoperatively, he was found to have acute-on-chronic osteomyelitis in T10 and T11, epidural abscess, and discitis in T12-L1. Tissue and wound culture grew Salmonella Typhi and with antibiotics susceptibility guidance he was treated with intravenous ceftriaxone for a period of six weeks. He recovered well with no neurological deficits. PMID:27034871

  19. Inactivation of Salmonellae in Frozen Catfish by Gamma Irradiation

    International Nuclear Information System (INIS)

    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 D10 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 103.2 Salmonella Enteritidis that may occasionally present in frozen catfish

  20. Molecular diagnosis of Salmonella species in captive psittacine birds.

    Science.gov (United States)

    Allgayer, M C; Lima-Rosa, C A V; Weimer, T A; Rodenbusch, C R; Pereira, R A; Streck, A F; Oliveira, S D; Canal, C W

    2008-06-21

    Cloacal swabs were collected from 280 captive psittacine birds belonging to 13 species. Samples of dna were tested by PCR using a pair of primers that amplify a 284 base pair fragment of the Salmonella genus invA gene, and the PCR-positive samples were tested by standard microbiological techniques. Thirteen per cent of the samples were positive by PCR, but negative by microbiological techniques. The infection rates were significantly different among the 13 species, the most commonly infected being Amazona amazonica (28 per cent) and Amazona pretrei (20 per cent). Specific tests for Salmonella Typhimurium Salmonella Enteritidis, Salmonella Pullorum and Salmonella Gallinarum did not produce positive results. PMID:18567929

  1. 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.

  2. Molecular Detection of Salmonella Serovar Isolated from Eggs

    Directory of Open Access Journals (Sweden)

    Monadi, M. (MSc

    2015-05-01

    Full Text Available Background and Objective: Salmonellosis is the most common type of food poisoning in developed and developing countries that is caused by Salmonella serotype. Hence, we aimed to identify the Salmonella serovars in eggs obtained from Kohgiluyeh and Boyerahmad province and to evaluate antibiotic resistance of the isolated strains. Material and Methods: In this study, 210 eggs were collected from Kohgiluyeh and Boyerahmad Province. The bacteria were isolated and identified using biochemical tests. After extraction of genomic DNA, Salmonella gender, Salmonella enteritidis and Salmonella typhimurium were investigated by invA, fliC and sefA primers, respectively, using Multiplex PCR method. Results: Of 210, 14 (6.66% were contaminated with Salmonella. Of these, 12 (5.71% were Salmonella typhimurium and 2 (0.95% were related to Salmonella spp. None of the samples were contaminated with Salmonella enteritidis. The highest resistance was related to penicillin (100% and neomycin (78.57%. Conclusion: Salmonella typhimurium is the predominant serovar causing contamination in the eggs of this Province. Given the wide spread of antibiotic resistance in different serotypes of Salmonella, we recommend avoiding of indiscriminate use of antibiotics in livestock and poultry

  3. Seroincidence of non-typhoid Salmonella infections

    DEFF Research Database (Denmark)

    Emborg, H-D; Simonsen, J; Jørgensen, C S;

    2016-01-01

    enabled a back-calculation of the annual seroincidence of Salmonella based on measurements of specific antibodies. The aim of the present study was to determine the seroincidence in two convenience samples from 2012 (Danish blood donors, n = 500, and pregnant women, n = 637) and a community-based sample...... of healthy individuals from 2006 to 2007 (n = 1780). The lowest antibody levels were measured in the samples from the community cohort and the highest in pregnant women. The annual Salmonella seroincidences were 319 infections/1000 pregnant women [90% credibility interval (CrI) 210-441], 182/1000 in...

  4. Salmonellae in foods and animal feeding stuffs

    International Nuclear Information System (INIS)

    After the problem of Salmonella infections in foods and feeding stuffs is emphasized, an account is given of the current ways of manufacturing bone meal, meat meal, blood meal, fish meal, fish flour, egg products and coconut. The effectiveness in eliminating salmonellae and the chance and possible sources of recontamination are described for each production method. Besides heat treatment, fumigation by ethylene oxide and irradiation with gamma rays are considered. The bacteriological tests required to establish the effectiveness of treatment are also discussed, as well as the effect of the treatment on the nutritive value of the product. (author). 50 refs, 4 tabs

  5. Occurrence of Salmonella sp in laying hens

    OpenAIRE

    Gama NMSQ; Berchieri Jr A; SA Fernandes

    2003-01-01

    This study was carried out to investigate the presence of Salmonella sp in flocks of white laying hens. In different farms, the transport boxes of twelve flocks were inspected at arrival for the presence of Salmonella. Four positive (A, B, L and M) and one negative (I) flocks were monitored at each four weeks using bacteriological examination of cecal fresh feces up to 52 weeks. Birds were also evaluated at 52 weeks, when 500 eggs were taken randomly, and at 76 weeks, after forced molt. Salmo...

  6. Rapid radiometric method for detection of Salmonella in foods

    International Nuclear Information System (INIS)

    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

  7. Source attribution of human Salmonella cases in Sweden

    DEFF Research Database (Denmark)

    Wahlström, H.; Andersson, Y.; Plym-Forshell, L.; Pires, Sara Monteiro

    2010-01-01

    associated with outbreaks. We estimated that 6.4% were associated with imported food, 0.5% with food-producing animals, and 0.6% with wildlife. Overall, 7.7% could not be attributed to any source. We concluded that domestic food-producing animals are not an important source for Salmonella in humans in Sweden......The aim of this study was to identify the sources of sporadic domestic Salmonella cases in Sweden and to evaluate the usefulness of a source-attribution model in a country in which food animals are virtually free from Salmonella. The model allocates human sporadic domestic Salmonella cases to...... different sources according to distribution of Salmonella subtypes in the different sources. Sporadic domestic human Salmonella cases (n=1086) reported between July 2004 and June 2006 were attributed to nine food-animal and wildlife sources. Of all Salmonella cases, 82% were acquired abroad and 2.9% were...

  8. PoxA, yjeK, and elongation factor P coordinately modulate virulence and drug resistance in Salmonella enterica

    DEFF Research Database (Denmark)

    Navarre, William Wiley; Zou, S Betty; Roy, Hervé;

    2010-01-01

    We report an interaction between poxA, encoding a paralog of lysyl tRNA-synthetase, and the closely linked yjeK gene, encoding a putative 2,3-beta-lysine aminomutase, that is critical for virulence and stress resistance in Salmonella enterica. Salmonella poxA and yjeK mutants share extensive...... phenotypic pleiotropy, including attenuated virulence in mice, an increased ability to respire under nutrient-limiting conditions, hypersusceptibility to a variety of diverse growth inhibitors, and altered expression of multiple proteins, including several encoded on the SPI-1 pathogenicity island. Pox......A mediates posttranslational modification of bacterial elongation factor P (EF-P), analogous to the modification of the eukaryotic EF-P homolog, eIF5A, with hypusine. The modification of EF-P is a mechanism of regulation whereby PoxA acts as an aminoacyl-tRNA synthetase that attaches an amino acid to a...

  9. Murine antibody response to oral infection with live aroA recombinant Salmonella dublin vaccine strains expressing filamentous hemagglutinin antigen from Bordetella pertussis.

    OpenAIRE

    Molina, N C; Parker, C D

    1990-01-01

    Two plasmids which express either nearly intact or truncated filamentous hemagglutinin (FHA) from Bordetella pertussis and which are marked with a tetracycline resistance (Tcr) gene were transformed into Salmonella dublin SL1438, an aroA deletion mutant intended for use as an attenuated oral vaccine against salmonellosis. These S. dublin recombinants, when fed to mice, induced serum immunoglobulin, immunoglobulin M (IgM), and sometimes IgA antibody responses to FHA and S. dublin. In addition,...

  10. Empiema causado por Salmonella typhimurium Pleural empyema caused by Salmonella typhimurium: A case report

    Directory of Open Access Journals (Sweden)

    MARÍA DEL MAR TACCHINI A

    2010-06-01

    Full Text Available El género Salmonella se caracteriza por causar infecciones en el tracto gastrointestinal, debido a la ingesta de alimentos o agua contaminada. También puede causar, con menor frecuencia, infecciones localizadas en diferentes órganos; esto se asocia con inmunodepresión. En este caso se describe un paciente con infección pleuropulmonar por Salmonella typhimurium, que no reportó antecedentes de diarrea previa. Evolucionó favorablemente con tratamiento adecuado.Salmonella species are commonly associated with acute gastroenteritis due to ingestion of contaminated food or water. Extraintestinal infections are less frequent, and most of them occur in immunocompromised patients. We report a case of pleural empyema caused by Salmonella typhimurium, without previous diarrhea or fever. The patient evolved favorably after receiving adequate treatment.

  11. 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,

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

    OpenAIRE

    Shima Shaigan nia; Fateme Rostami; Farhad Safarpour dehkordi; Ebrahim Rahimi; Emad Yahaghi; Ebrahim Khodaverdi Darian; Mahrokh Bagheri Moghadam

    2014-01-01

    Background and Aim: Nutritional and economic importance of milk and dairy products is undeniable. In a day, Millions of people use from these products in their daily deals but unfortunately the hygienic quality of milk and dairy products can be changed due to presence of microbial pathogens. Salmonella enteritidis and Salmonella typhimurium are two important milk-borne pathogens. Their pathogenicity is occurred by several putative virulence genes. This study was carried out for investigate th...

  13. Salmonella Gene rma (ramA) and Multiple-Drug-Resistant Salmonella enterica Serovar Typhimurium

    OpenAIRE

    2004-01-01

    MarA and its homologue, RamA, have been implicated in multidrug resistance (MDR). RamA overexpression in Salmonella enterica serovar Typhimurium and Escherichia coli conferred MDR independently of marA. Inactivation of ramA did not affect the antibiotic susceptibilities of wild-type S. enterica serovar Typhimurium or 15 unrelated clinical MDR isolates. Thus, ramA overexpression is not a common MDR mechanism in Salmonella.

  14. Limited Interleukin-18 Response in Salmonella-Infected Murine Macrophages and in Salmonella-Infected Mice

    OpenAIRE

    Elhofy, Adam; Bost, Kenneth L

    1999-01-01

    Optimal immune responses against an intracellular bacterial pathogen, such as Salmonella, involve the production of gamma interferon (IFN-γ), which activates macrophages. It has recently been suggested that, interleukin-18 (IL-18), in addition to IL-12, contributes to the induction of IFN-γ following infection. Given this hypothesis, an optimal host immune response against intracellular bacterial pathogens would include the induction of IL-18 secretion by macrophages due to Salmonella infecti...

  15. RAPID DETECTION OF Salmonella IN SHRIMP BY POLYMERASE CHAIN REACTION [Deteksi Cepat Salmonella pada Udang dengan Polymerase Chain Reaction

    Directory of Open Access Journals (Sweden)

    Ulfah Amalia

    2014-06-01

    Full Text Available Shrimp is an important non-oil commodity for foreign trade in Indonesia. However, rejection of shrimp exports by the importing countries is still commonly encountered. In 2011, the USFDA recorded two cases of Salmonella spp. contamination in shrimp products from two shrimp processing companies in Indonesia. Analysis of Salmonella spp. in seafood is generally performed using a conventional method which takes at least 5 days. The objective of the study is to get a Salmonellae rapid detection method in shrimp by PCR. In this study, optimization of PCR protocol method to detect Salmonella invA gene was conducted using six different annealing temperatures (59, 59.5, 60.8, 62, 64 and 64.5°C. The results showed that 64°C was the optimum annealing temperature to detect the 284 bp fragment of Salmonella invA gene. The PCR based detection method has a DNA detection limit of 27.81ug/mL and 10°CFU/mL of viable salmonellae with 100% specificity. The PCR protocol is capable of detecting six different Salmonella serovars (S. Enteritidis, S. Hadar, S. Heidelberg, S. Kentucky, S. Paratyphi and S. Typhimurium but none of the non salmonellae isolates. Application of the PCR assay on Salmonella in shrimp after the selective enrichment step suggested that all 16 samples were positive for Salmonella. At the same time, the conventional method could only detected 3 samples for Salmonella positive.

  16. Ultrasonic Attenuation in Zircaloy-4

    International Nuclear Information System (INIS)

    In this work the relationship between Zircaloy-4 grain size and ultrasonic attenuation behavior was studied for longitudinal waves in the frequency range of 10-90 MHz. The attenuation was analyzed as a function of frequency for samples with different mechanical and heat treatments having recrystallized and Widmanstatten structures with different grain size. The attenuation behavior was analyzed by different scattering models, depending on grain size, wavelength and frequency

  17. Chopping-Wheel Optical Attenuator

    Science.gov (United States)

    Leviton, Douglas B.

    1988-01-01

    Star-shaped rotating chopping wheel provides adjustable time-averaged attenuation of narrow beam of light without changing length of optical path or spectral distribution of light. Duty cycle or attenuation factor of chopped beam controlled by adjusting radius at which beam intersects wheel. Attenuation factor independent of wavelength. Useful in systems in which chopping frequency above frequency-response limits of photodetectors receiving chopped light. Used in systems using synchronous detection with lock-in amplifiers.

  18. A metabolic intermediate of the fructose-asparagine utilization pathway inhibits growth of a Salmonella fraB mutant.

    Science.gov (United States)

    Sabag-Daigle, Anice; Blunk, Henry M; Sengupta, Anindita; Wu, Jikang; Bogard, Alexander J; Ali, Mohamed M; Stahl, Christopher; Wysocki, Vicki H; Gopalan, Venkat; Behrman, Edward J; Ahmer, Brian M M

    2016-01-01

    Insertions in the Salmonella enterica fra locus, which encodes the fructose-asparagine (F-Asn) utilization pathway, are highly attenuated in mouse models of inflammation (>1000-fold competitive index). Here, we report that F-Asn is bacteriostatic to a fraB mutant (IC50 19 μM), but not to the wild-type or a fra island deletion mutant. We hypothesized that the presence of FraD kinase and absence of FraB deglycase causes build-up of a toxic metabolite: 6-phosphofructose-aspartate (6-P-F-Asp). We used biochemical assays to assess FraB and FraD activities, and mass spectrometry to confirm that the fraB mutant accumulates 6-P-F-Asp. These results, together with our finding that mutants lacking fraD or the fra island are not attenuated in mice, suggest that the extreme attenuation of a fraB mutant stems from 6-P-F-Asp toxicity. Salmonella FraB is therefore an excellent drug target, a prospect strengthened by the absence of the fra locus in most of the gut microbiota. PMID:27403719

  19. A metabolic intermediate of the fructose-asparagine utilization pathway inhibits growth of a Salmonella fraB mutant

    Science.gov (United States)

    Sabag-Daigle, Anice; Blunk, Henry M.; Sengupta, Anindita; Wu, Jikang; Bogard, Alexander J.; Ali, Mohamed M.; Stahl, Christopher; Wysocki, Vicki H.; Gopalan, Venkat; Behrman, Edward J.; Ahmer, Brian M. M.

    2016-01-01

    Insertions in the Salmonella enterica fra locus, which encodes the fructose-asparagine (F-Asn) utilization pathway, are highly attenuated in mouse models of inflammation (>1000-fold competitive index). Here, we report that F-Asn is bacteriostatic to a fraB mutant (IC50 19 μM), but not to the wild-type or a fra island deletion mutant. We hypothesized that the presence of FraD kinase and absence of FraB deglycase causes build-up of a toxic metabolite: 6-phosphofructose-aspartate (6-P-F-Asp). We used biochemical assays to assess FraB and FraD activities, and mass spectrometry to confirm that the fraB mutant accumulates 6-P-F-Asp. These results, together with our finding that mutants lacking fraD or the fra island are not attenuated in mice, suggest that the extreme attenuation of a fraB mutant stems from 6-P-F-Asp toxicity. Salmonella FraB is therefore an excellent drug target, a prospect strengthened by the absence of the fra locus in most of the gut microbiota. PMID:27403719

  20. Genes Required for the Fitness of Salmonella enterica Serovar Typhimurium during Infection of Immunodeficient gp91-/- phox Mice.

    Science.gov (United States)

    Grant, Andrew J; Oshota, Olusegun; Chaudhuri, Roy R; Mayho, Matthew; Peters, Sarah E; Clare, Simon; Maskell, Duncan J; Mastroeni, Pietro

    2016-04-01

    Salmonella entericacauses systemic diseases (typhoid and paratyphoid fever), nontyphoidal septicemia (NTS), and gastroenteritis in humans and other animals worldwide. An important but underrecognized emerging infectious disease problem in sub-Saharan Africa is NTS in children and immunocompromised adults. A current goal is to identifySalmonellamutants that are not pathogenic in the absence of key components of the immune system such as might be found in immunocompromised hosts. Such attenuated strains have the potential to be used as live vaccines. We have used transposon-directed insertion site sequencing (TraDIS) to screen mutants ofSalmonella entericaserovar Typhimurium for their ability to infect and grow in the tissues of wild-type and immunodeficient mice. This was to identify bacterial genes that might be deleted for the development of live attenuated vaccines that would be safer to use in situations and/or geographical areas where immunodeficiencies are prevalent. The relative fitness of each of 9,356 transposon mutants, representing mutations in 3,139 different genes, was determined ingp91(-/-)phoxmice. Mutations in certain genes led to reduced fitness in both wild-type and mutant mice. To validate these results, these genes were mutated by allelic replacement, and resultant mutants were retested for fitness in the mice. A defined deletion mutant ofcysEwas attenuated in C57BL/6 wild-type mice and immunodeficientgp91(-/-)phoxmice and was effective as a live vaccine in wild-type mice. PMID:26787719

  1. Attachment of Salmonella spp. to pork meat

    DEFF Research Database (Denmark)

    Hansen, Trine; Riber, Leise; Löfström, Charlotta;

    2011-01-01

    Five strains of Salmonella, one wildtype and four knock-out mutants (the prg, flhDC, yhjH and fliC genes) were investigated based on their probability to attach and subsequently detach from a surface of pork fillet. The attachment followed by detachment was measured and modelled for two different...

  2. Serovars of Salmonella from captive reptiles

    DEFF Research Database (Denmark)

    Pedersen, Karl; Lassen-Nielsen, Anne Marie; Nordentoft, Steen;

    2009-01-01

    The distribution on serovars of 60 Salmonella isolates from reptiles kept in captivity in Denmark during the period 1995–2006 was investigated. The isolates were all recovered from clinical specimens submitted to the National Veterinary Institute. A majority of the samples were from reptiles in...

  3. Salmonella osteomyelitis by sickle cell anemia

    International Nuclear Information System (INIS)

    Case report of a 28 year old black sickle cell anemia patient with salmonella osteomyelitis of the radius. Aside from sickle cell anemia patients this skeletal complication of enteric salmonellosis is an extreme rarity. Description of the typical roentgenological features includes intracortical fissures and sequestration. (orig.)

  4. Nontyphoidal Salmonella Infection, Guangdong Province, China, 20121

    Science.gov (United States)

    Huang, Xi; Huang, Qiong; Dun, Zhongjun; Huang, Wei; Wu, Shuyu; Liang, Junhua; Deng, Xiaoling

    2016-01-01

    We used active and passive surveillance to estimate nontyphoidal Salmonella (NTS) infection during 2012 in Guangdong Province, China. Under passive surveillance, for every reported NTS infection, an estimated 414.8 cases occurred annually. Under active surveillance, an estimated 35.8 cases occurred. Active surveillance provides remarkable advantages in incidence estimate. PMID:26982074

  5. Regulatory Citrate Lyase Mutants of Salmonella typhimurium

    OpenAIRE

    Kulla, Hans G.

    1983-01-01

    Citrate lyase, the key enzyme of anaerobic citrate catabolism, could not be deleted from Salmonella typhimurium. The only class of mutants found had a mode of covalent regulation that strongly resembled the Escherichia coli system: citrate lyase was only active, i.e., acetylated, when a cosubstrate was present.

  6. Regulatory citrate lyase mutants of Salmonella typhimurium.

    Science.gov (United States)

    Kulla, H G

    1983-01-01

    Citrate lyase, the key enzyme of anaerobic citrate catabolism, could not be deleted from Salmonella typhimurium. The only class of mutants found had a mode of covalent regulation that strongly resembled the Escherichia coli system: citrate lyase was only active, i.e., acetylated, when a cosubstrate was present. PMID:6336740

  7. Persistence of salmonella Typhimurium in Nopal

    Science.gov (United States)

    Having documented information available on the capability of Salmonella to remain in the cladode tissue it is important to understand the role of nopal on the lifecycle of enteropathogenic bacteria in humans, as well as for management and control programs of theses pathogens in plants. Because of th...

  8. Salmonella typhi time to change empiric treatment

    DEFF Research Database (Denmark)

    Gade, C.; Engberg, J.; Weis, N.

    2008-01-01

    In the present case series report we describe seven recent cases of typhoid fever. All the patients were travellers returning from Pakistan, where typhoid is endemic. Salmonella typhi isolated from the patients by blood culture were reported as intermediary susceptible to fluoroquinolones in six...

  9. Attachment of Salmonella spp. to pork meat

    DEFF Research Database (Denmark)

    Hansen, Trine; Riber, Leise; Löfström, Charlotta; Hoorfar, Jeffrey

    Five strains of Salmonella, one wildtype and four knock-out mutants (the prg, flhDC, yhjH and fliC genes) were investigated based on their probability to attach and subsequently detach from a surface of pork fillet. The attachment followed by detachment was measured and modelled for two different...

  10. Sexually acquired Salmonella Typhi urinary tract infection.

    Science.gov (United States)

    Wielding, Sally; Scott, Gordon

    2016-05-01

    We report a case of isolated urinarySalmonella entericaserotype Typhi in an HIV-positive man who has sex with men. He was clinically well and blood and stool cultures were negative, indicating that this may have been a sexually acquired urinary tract infection. PMID:25953964

  11. Meningism following Salmonella virchow food poisoning.

    OpenAIRE

    Norris, P. G.

    1986-01-01

    Thirty six patients were admitted to hospital as a result of Salmonella virchow infection during an outbreak of food poisoning in Essex in 1984. Out of 12 patients with evidence of bloodstream invasion, one third presented primarily with meningism and attention is drawn to this unusual clinical picture.

  12. Salmonella Typhimurium Outbreak Associated with Veterinary Clinic

    OpenAIRE

    Cherry, Bryan; Burns, Amy; Johnson, Geraldine S.; Pfeiffer, Heidi; Dumas, Nellie; Barrett, Donna; McDonough, Patrick L.; Eidson, Millicent

    2004-01-01

    A Salmonella enterica serovar Typhimurium outbreak was associated with a veterinary clinic. Confirmed cases were in one cat, two veterinary technicians, four persons associated with clinic patients, and a nurse not linked to the clinic. This outbreak emphasizes the importance of strong public health ties to the animal health community.

  13. Salmonella Agona Outbreak from Contaminated Aniseed, Germany

    OpenAIRE

    Koch, Judith; Schrauder, Annette; Alpers, Katharina; Werber, Dirk; Frank, Christina; Prager, Rita; Rabsch, Wolfgang; Broll, Susanne; Feil, Fabian; Roggentin, Peter; Bockemühl, Jochen; Tschäpe, Helmut; Ammon, Andrea; Stark, Klaus

    2005-01-01

    A nationwide outbreak of Salmonella Agona caused by aniseed-containing herbal tea occurred from October 2002 through July 2003 among infants in Germany. Consumers should adhere strictly to brewing instructions, although in exceptional cases this precaution may not be protective, particularly when preparing tea for vulnerable age groups.

  14. Persistence of salmonella typhimurium in nopal cladodes

    Science.gov (United States)

    Fresh produce associated outbreaks have increased in the last few years. E.coli O157:H7 and Salmonella have been causative agents of infection in these outbreaks. Fresh produce is consumed raw, and in the absence of terminal kill treatment, it is imperative to understand sources of contamination o...

  15. Water Frogs, Aquariums, and Salmonella -- Oh My!

    Centers for Disease Control (CDC) Podcasts

    2009-12-09

    This CDC Kidtastics podcast discusses how people can get Salmonella from water frogs and aquariums.  Created: 12/9/2009 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 12/9/2009.

  16. 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.

  17. Virulence factors of Salmonella enterica serovar Enteritidis

    NARCIS (Netherlands)

    Zhao, Y.

    2002-01-01

    Salmonella enterica serovar Enteritidis is one of the major etiologic agents of human food-borne gastrointestinal infections. Efforts to control the number of serovar Enteritidis infections have had a limited success, in part because of the lack of knowledge of the molecular mechanisms that contribu

  18. LINE-ABOVE-GROUND ATTENUATOR

    Science.gov (United States)

    Wilds, R.B.; Ames, J.R.

    1957-09-24

    The line-above-ground attenuator provides a continuously variable microwave attenuator for a coaxial line that is capable of high attenuation and low insertion loss. The device consists of a short section of the line-above- ground plane type transmission lime, a pair of identical rectangular slabs of lossy material like polytron, whose longitudinal axes are parallel to and indentically spaced away from either side of the line, and a geared mechanism to adjust amd maintain this spaced relationship. This device permits optimum fineness and accuracy of attenuator control which heretofore has been difficult to achieve.

  19. Diverse genome structures of Salmonella paratyphi C

    Directory of Open Access Journals (Sweden)

    Qi Danni

    2007-08-01

    Full Text Available Abstract Background Salmonella paratyphi C, like S. typhi, is adapted to humans and causes typhoid fever. Previously we reported different genome structures between two strains of S. paratyphi C, which suggests that S. paratyphi C might have a plastic genome (large DNA segments being organized in different orders or orientations on the genome. As many but not all host-adapted Salmonella pathogens have large genomic insertions as well as the supposedly resultant genomic rearrangements, bacterial genome plasticity presents an extraordinary evolutionary phenomenon. Events contributing to genomic plasticity, especially large insertions, may be associated with the formation of particular Salmonella pathogens. Results We constructed a high resolution genome map in S. paratyphi C strain RKS4594 and located four insertions totaling 176 kb (including the 90 kb SPI7 and seven deletions totaling 165 kb relative to S. typhimurium LT2. Two rearrangements were revealed, including an inversion of 1602 kb covering the ter region and the translocation of the 43 kb I-CeuI F fragment. The 23 wild type strains analyzed in this study exhibited diverse genome structures, mostly as a result of recombination between rrn genes. In at least two cases, the rearrangements involved recombination between genomic sites other than the rrn genes, possibly homologous genes in prophages. Two strains had a 20 kb deletion between rrlA and rrlB, which is a highly conservative region and no deletion has been reported in this region in any other Salmonella lineages. Conclusion S. paratyphi C has diverse genome structures among different isolates, possibly as a result of large genomic insertions, e.g., SPI7. Although the Salmonella typhoid agents may not be more closely related among them than each of them to other Salmonella lineages, they may have evolved in similar ways, i.e., acquiring typhoid-associated genes followed by genome structure rearrangements. Comparison of multiple

  20. Thermal inactivation of Salmonella spp. in pork burger patties.

    Science.gov (United States)

    Gurman, P M; Ross, T; Holds, G L; Jarrett, R G; Kiermeier, A

    2016-02-16

    Predictive models, to estimate the reduction in Escherichia coli O157:H7 concentration in beef burgers, have been developed to inform risk management decisions; no analogous model exists for Salmonella spp. in pork burgers. In this study, "Extra Lean" and "Regular" fat pork minces were inoculated with Salmonella spp. (Salmonella 4,[5],12,i:-, Salmonella Senftenberg and Salmonella Typhimurium) and formed into pork burger patties. Patties were cooked on an electric skillet (to imitate home cooking) to one of seven internal temperatures (46, 49, 52, 55, 58, 61, 64 °C) and Salmonella enumerated. A generalised linear logistic regression model was used to develop a predictive model for the Salmonella concentration based on the internal endpoint temperature. It was estimated that in pork mince with a fat content of 6.1%, Salmonella survival will be decreased by -0.2407log10 CFU/g for a 1 °C increase in internal endpoint temperature, with a 5-log10 reduction in Salmonella concentration estimated to occur when the geometric centre temperature reaches 63 °C. The fat content influenced the rate of Salmonella inactivation (P=0.043), with Salmonella survival increasing as fat content increased, though this effect became negligible as the temperature approached 62 °C. Fat content increased the time required for patties to achieve a specified internal temperature (P=0.0106 and 0.0309 for linear and quadratic terms respectively), indicating that reduced fat pork mince may reduce the risk of salmonellosis from consumption of pork burgers. Salmonella serovar did not significantly affect the model intercepts (P=0.86) or slopes (P=0.10) of the fitted logistic curve. This predictive model can be applied to estimate the reduction in Salmonella in pork burgers after cooking to a specific endpoint temperature and hence to assess food safety risk. PMID:26686598

  1. Identification of genes to differentiate closely related Salmonella lineages.

    Directory of Open Access Journals (Sweden)

    Qing-Hua Zou

    Full Text Available BACKGROUND: Salmonella are important human and animal pathogens. Though highly related, the Salmonella lineages may be strictly adapted to different hosts or cause different diseases, from mild local illness like gastroenteritis to fatal systemic infections like typhoid. Therefore, rapid and accurate identification of Salmonella is essential for timely and correct diagnosis of Salmonella infections. The current identification methods such as 16S rRNA sequencing and multilocus sequence typing are expensive and time consuming. Additionally, these methods often do not have sufficient distinguishing resolution among the Salmonella lineages. METHODOLOGIES/PRINCIPAL FINDINGS: We compared 27 completely sequenced Salmonella genomes to identify possible genomic features that could be used for differentiation of individual lineages. We concatenated 2372 core genes in each of the 27 genomes and constructed a neighbor-joining tree. On the tree, strains of each serotype were clustered tightly together and different serotypes were unambiguously separated with clear genetic distances, demonstrating systematic genomic divergence among the Salmonella lineages. We made detailed comparisons among the 27 genomes and identified distinct sets of genomic differences, including nucleotide variations and genomic islands (GIs, among the Salmonella lineages. Two core genes STM4261 and entF together could unambiguously distinguish all Salmonella lineages compared in this study. Additionally, strains of a lineage have a common set of GIs and closely related lineages have similar sets of GIs. CONCLUSIONS: Salmonella lineages have accumulated distinct sets of mutations and laterally acquired DNA (e.g., GIs in evolution. Two genes entF and STM4261 have diverged sufficiently among the Salmonella lineages to be used for their differentiation. Further investigation of the distinct sets of mutations and GIs will lead to novel insights into genomic evolution of Salmonella and

  2. Fiber optic attenuator

    Science.gov (United States)

    Buzzetti, Mike F. (Inventor)

    1994-01-01

    A fiber optic attenuator of the invention is a mandrel structure through which a bundle of optical fibers is wrapped around in a complete circle. The mandrel structure includes a flexible cylindrical sheath through which the bundle passes. A set screw on the mandrel structure impacts one side of the sheath against two posts on the opposite side of the sheath. By rotating the screw, the sheath is deformed to extend partially between the two posts, bending the fiber optic bundle to a small radius controlled by rotating the set screw. Bending the fiber optic bundle to a small radius causes light in each optical fiber to be lost in the cladding, the amount depending upon the radius about which the bundle is bent.

  3. A Salmonella small non-coding RNA facilitates bacterial invasion and intracellular replication by modulating the expression of virulence factors.

    Directory of Open Access Journals (Sweden)

    Hao Gong

    2011-09-01

    Full Text Available Small non-coding RNAs (sRNAs that act as regulators of gene expression have been identified in all kingdoms of life, including microRNA (miRNA and small interfering RNA (siRNA in eukaryotic cells. Numerous sRNAs identified in Salmonella are encoded by genes located at Salmonella pathogenicity islands (SPIs that are commonly found in pathogenic strains. Whether these sRNAs are important for Salmonella pathogenesis and virulence in animals has not been reported. In this study, we provide the first direct evidence that a pathogenicity island-encoded sRNA, IsrM, is important for Salmonella invasion of epithelial cells, intracellular replication inside macrophages, and virulence and colonization in mice. IsrM RNA is expressed in vitro under conditions resembling those during infection in the gastrointestinal tract. Furthermore, IsrM is found to be differentially expressed in vivo, with higher expression in the ileum than in the spleen. IsrM targets the mRNAs coding for SopA, a SPI-1 effector, and HilE, a global regulator of the expression of SPI-1 proteins, which are major virulence factors essential for bacterial invasion. Mutations in IsrM result in disregulation of expression of HilE and SopA, as well as other SPI-1 genes whose expression is regulated by HilE. Salmonella with deletion of isrM is defective in bacteria invasion of epithelial cells and intracellular replication/survival in macrophages. Moreover, Salmonella with mutations in isrM is attenuated in killing animals and defective in growth in the ileum and spleen in mice. Our study has shown that IsrM sRNA functions as a pathogenicity island-encoded sRNA directly involved in Salmonella pathogenesis in animals. Our results also suggest that sRNAs may represent a distinct class of virulence factors that are important for bacterial infection in vivo.

  4. 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.

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

    OpenAIRE

    Mooijman KA; MGB

    2006-01-01

    The eleventh workshop organised by the Community Reference Laboratory for Salmonella (CRL-Salmonella) was held in Saint Malo, France on 9 May 2006. Participants included representatives of the National Reference Laboratories for Salmonella (NRLs-Salmonella) of the Member States of the European Union and of the European Commission. Presentations were given by representatives of the European Commission and the CRL-Salmonella. Subjects discussed were European legislation on Salmonella criteria f...

  6. Use of Rambach Propylene Glycol Containing Agar for identification of Salmonella spp.

    OpenAIRE

    Gruenewald, R; Henderson, R. W.; Yappow, S

    1991-01-01

    When grown on Rambach Propylene Glycol Containing Agar (Rambach agar), 216 of 230 (93.9%) Salmonella organisms isolated from patients and 54 of 62 (87.1%) Salmonella stock cultures produced a crimson-colored growth. Of the 14 clinical Salmonella isolates which displayed colors other than crimson, 8 were Salmonella typhi, 2 were Salmonella paratyphi A, and 4 belonged to other commonly isolated serotypes. All eight Salmonella stock cultures which failed to produce a crimson color belonged to ra...

  7. Identification and sequence analysis of lpfABCDE, a putative fimbrial operon of Salmonella typhimurium.

    OpenAIRE

    Bäumler, A J; Heffron, F

    1995-01-01

    A chromosomal region present in Salmonella typhimurium but absent from related species was identified by hybridization. A DNA probe originating from 78 min on the S. typhimurium chromosome hybridized with DNA from Salmonella enteritidis, Salmonella heidelberg, and Salmonella dublin but not with DNA from Salmonella typhi, Salmonella arizonae, Escherichia coli, and Shigella serotypes. Cloning and sequence analysis revealed that the corresponding region of the S. typhimurium chromosome encodes a...

  8. Central regulatory role for the RpoS sigma factor in expression of Salmonella dublin plasmid virulence genes.

    OpenAIRE

    Chen, C Y; Buchmeier, N A; Libby, S.; Fang, F C; Krause, M.; Guiney, D G

    1995-01-01

    The plasmid virulence genes spvABCD of Salmonella spp. are regulated by SpvR and the stationary-phase sigma factor RpoS. The transcription of spv genes is induced during the post-exponential phase of bacterial growth in vitro. We sought to investigate the relationship between growth phase and RpoS in spv regulation. rpoS insertion mutations were constructed in S. dublin Lane and plasmid-cured LD842 strains, and the mutants were found to be attenuated for virulence and deficient in spv gene ex...

  9. SpvC is a Salmonella effector with phosphothreonine lyase activity on host mitogen-activated protein kinases

    OpenAIRE

    Mazurkiewicz, Piotr; Thomas, Jerry; Thompson, Jessica A.; Liu, Mei; Arbibe, Laurence; Sansonetti, Philippe; Holden, David W.

    2008-01-01

    SpvC is encoded by the Salmonella virulence plasmid. We have investigated the biochemical function of SpvC and the mechanism by which it is secreted by bacteria and translocated into infected macrophages. We constructed a strain carrying a deletion in spvC and showed that the strain is attenuated for systemic virulence in mice. SpvC can be secreted in vitro by either the SPI-1 or SPI-2 type III secretion systems. Cell biological and genetic experiments showed that translocation of the protein...

  10. Adjustable Optical-Fiber Attenuator

    Science.gov (United States)

    Buzzetti, Mike F.

    1994-01-01

    Adjustable fiber-optic attenuator utilizes bending loss to reduce strength of light transmitted along it. Attenuator functions without introducing measurable back-reflection or insertion loss. Relatively insensitive to vibration and changes in temperature. Potential applications include cable television, telephone networks, other signal-distribution networks, and laboratory instrumentation.

  11. 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. PMID:27527766

  12. THE DYNAMICS OF ANTIMICROBIAL RESISTANCE OF Salmonella typhimurium ISOLATES.

    OpenAIRE

    Erleta Peqini; Zheni Brahimaj; Sotir Mali; Klementina Puto; Ariola Devolli; Naxhije Hila; Aida Dervishi

    2011-01-01

    Salmonella typhimurium is the most common pathogen isolated in foodstuffs toxin infections. The development of antibiotic resistance in Salmonella typhimurium over the last twenty years is caused by an extensive application of some antibiotics. The study of antimicrobial resistance of Salmonella typhimurium isolates helps the physicians in using the indispensable antibiotic and replacing the resistant antibiotics with new ones. The aim of this study was to determine the prevalence of antimicr...

  13. Prolonged inhibition of bacterial protein synthesis abolishes Salmonella invasion.

    OpenAIRE

    MacBeth, K J; Lee, C. A.

    1993-01-01

    We have found that prolonged inhibition of bacterial protein synthesis abolishes the ability of Salmonella typhimurium to enter HEp-2 cells. Our results suggest that an essential invasion factor has a functional half-life that is seen as a gradual loss of invasiveness in the absence of protein synthesis. Therefore, Salmonella invasiveness appears to be a transient phenotype that is lost unless protein synthesis is maintained. This finding may explain why salmonellae grown to stationary phase ...

  14. Salmonella Typhi: from a Human Pathogen to a Vaccine Vector

    OpenAIRE

    Zhang, Xiao-Lian; Jeza, Victor Tunje; Pan, Qin

    2008-01-01

    Salmonella (S.) typhi is an important intracellular pathogen. Among the more than 2,300 closely-related Salmonella serovars bacteria recognized, S. typhi is the only one that is pathogenic exclusively for humans, in whom it causes typhoid or enteric fever. The pathogen has been around for many years and many studies have been done in an effort to combat it. Molecular and biologic features of S. typhi and host factors and immune responses involved in Salmonella invasion have been extensively s...

  15. Antibiotic Resistance of Salmonella Enteritidis of Human and Chicken Origin

    OpenAIRE

    GONCAGÜL, Gülşen; GÜNAYDIN, Elçin; ÇARLI, K. Tayfun

    2004-01-01

    The aim of this study was to examine the relationship between antibiotic resistance patterns among Salmonella enterica subsp. enterica Serovar Enteritidis isolates (Salmonella Enteritidis) of human and poultry origin. Antibiotic resistance of 97 Salmonella Enteritidis isolates from 25 chicken meat, 25 chicken intestine and 47 human fecal samples was examined using the National Committee for Clinical Laboratory Standards (NCCLS, 1997) disk diffusion method. Resistance patterns of the isolates ...

  16. Invasive Salmonella dublin Infections Associated With Drinking Raw Milk

    OpenAIRE

    Fierer, Joshua

    1983-01-01

    Salmonella dublin is a serotype of Salmonella that is host-adapted to cattle and rarely infects people. In one year (1980-1981) we diagnosed five cases of salmonellosis due to S dublin at the Veterans Administration Medical Center, San Diego. Four patients had positive blood cultures and one died. A sixth patient, diagnosed in 1978, had a mycotic aortic aneurysm but survived. Compared with nine patients who had Salmonella infections due to other serotypes, the S dublin patients were older, ha...

  17. Salmonella induces prominent gene expression in the rat colon

    Directory of Open Access Journals (Sweden)

    Roosing Susanne

    2007-09-01

    Full Text Available Abstract Background Salmonella enteritidis is suggested to translocate in the small intestine. In vivo it induces gene expression changes in the ileal mucosa and Peyer's patches. Stimulation of Salmonella translocation by dietary prebiotics fermented in colon suggests involvement of the colon as well. However, effects of Salmonella on colonic gene expression in vivo are largely unknown. We aimed to characterize time dependent Salmonella-induced changes of colonic mucosal gene expression in rats using whole genome microarrays. For this, rats were orally infected with Salmonella enteritidis to mimic a foodborne infection and colonic gene expression was determined at days 1, 3 and 6 post-infection (n = 8 rats per time-point. As fructo-oligosaccharides (FOS affect colonic physiology, we analyzed colonic mucosal gene expression of FOS-fed versus cellulose-fed rats infected with Salmonella in a separate experiment. Colonic mucosal samples were isolated at day 2 post-infection. Results Salmonella affected transport (e.g. Chloride channel calcium activated 6, H+/K+ transporting Atp-ase, antimicrobial defense (e.g. Lipopolysaccharide binding protein, Defensin 5 and phospholipase A2, inflammation (e.g. calprotectin, oxidative stress related genes (e.g. Dual oxidase 2 and Glutathione peroxidase 2 and Proteolysis (e.g. Ubiquitin D and Proteosome subunit beta type 9. Furthermore, Salmonella translocation increased serum IFNγ and many interferon-related genes in colonic mucosa. The gene most strongly induced by Salmonella infection was Pancreatitis Associated Protein (Pap, showing >100-fold induction at day 6 after oral infection. Results were confirmed by Q-PCR in individual rats. Stimulation of Salmonella translocation by dietary FOS was accompanied by enhancement of the Salmonella-induced mucosal processes, not by induction of other processes. Conclusion We conclude that the colon is a target tissue for Salmonella, considering the abundant changes in

  18. 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.

  19. Meta-analysis of Chicken - Salmonella infection experiments.

    OpenAIRE

    te Pas Marinus FW; Hulsegge Ina; Schokker Dirkjan; Smits Mari A; Fife Mark; Zoorob Rima; Endale Marie-Laure; Rebel Johanna MJ

    2012-01-01

    Abstract Background Chicken meat and eggs can be a source of human zoonotic pathogens, especially Salmonella species. These food items contain a potential hazard for humans. Chickens lines differ in susceptibility for Salmonella and can harbor Salmonella pathogens without showing clinical signs of illness. Many investigations including genomic studies have examined the mechanisms how chickens react to infection. Apart from the innate immune response, many physiological mechanisms and pathways...

  20. Characterization of the spv Locus in Salmonella enterica Serovar Arizona

    OpenAIRE

    Libby, Stephen J.; Lesnick, Marc; Hasegawa, Patricia; Kurth, Michael; Belcher, Christopher; Fierer, Joshua; Guiney, Donald G.

    2002-01-01

    Salmonella enterica serovar Arizona (S. enterica subspecies IIIa) is a common Salmonella isolate from reptiles and can cause serious systemic disease in humans. The spv virulence locus, found on large plasmids in Salmonella subspecies I serovars associated with severe infections, was confirmed to be located on the chromosome of serovar Arizona. Sequence analysis revealed that the serovar Arizona spv locus contains homologues of spvRABC but lacks the spvD gene and contains a frameshift in spvA...

  1. Identification and characterization of Salmonella isolates from captured house sparrows

    OpenAIRE

    MIRZAIE, Sara; Hassanzadeh, Mohammad; ASHRAFI, Iradj

    2010-01-01

    The objectives of this study were to determine the prevalence of Salmonella in a population of house sparrows, which are commonly found around poultry houses, and to characterize the obtained Salmonella isolates via serotyping, multiplex polymerase chain reaction (PCR), and antibiotic resistance analysis. Samples of visceral organs (gastrointestinal tract, liver, and heart) from 470 house sparrows were subjected to culture and the results show that 18 (3.8%) were positive for Salmonella. Of t...

  2. A comparison between longitudinal shedding patterns of Salmonella Typhimurium and Salmonella Dublin on dairy farms.

    Science.gov (United States)

    Kirchner, M; McLaren, I; Clifton-Hadley, F A; Liebana, E; Wales, A D; Davies, R H

    2012-08-25

    Salmonella in cattle herds may behave as epidemic or endemic infections. An intensive longitudinal sampling study across all management groups and ages on six dairy farms in the UK was used to examine patterns of Salmonella shedding, following the prior identification of either Salmonella Dublin (SD) (three farms) or Salmonella Typhimurium (ST) (three farms) on the premises in the context of clinical salmonellosis. Individual faeces, pooled faeces and environmental samples (total 5711 samples), taken approximately every six weeks for 15-24 weeks, were cultured for Salmonella. SD was detected at low frequency (on any visit, 0.5-18.3 per cent of samples positive) and most consistently in calves. By contrast, ST was isolated at higher frequency (on any visit, 6.8-75 per cent of samples positive), and in higher numbers, up to 10(7) cfu/g faeces. Significantly more samples from calves were positive for ST than were positive for SD (50.6 per cent v 3.1 per cent; P < 0.001), which was also true for milking cows (46.3 per cent v 4.4 per cent; P < 0.001). The differences could help to explain the different patterns of bovine infection classically associated with these two serovars in the UK. No consistent effect upon shedding was seen among the ST-infected herds following vaccination. PMID:22859413

  3. DETEKSI Salmonella PADA NASI GORENG YANG DISEDIAKAN OLEH RESTORAN KERETA API KELAS EKONOMI [Detection of Salmonella on Fried Rice Served in Restaurant of Economic Class Train

    OpenAIRE

    Srianta; Elisa Rinihapsari

    2003-01-01

    Salmonella is a group of infective pathogenic bacteria for human being that cause many food borne disease outbreaks. Human, animal and some animal-based food products are whicle for Salmonella. Public transportation i.e. train/railway, often serve foods that potentially contaminated with Salmonella. Study on Salmonella detection on fried rice served in economic class train restaurant is necessary for controlling its safety and quality. Standard method was used to detect Salmonella on fried ri...

  4. Complete Genome and Methylome Sequences of Salmonella enterica subsp. enterica Serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica Serovar Sloterdijk (ATCC 15791).

    Science.gov (United States)

    Yao, Kuan; Muruvanda, Tim; Roberts, Richard J; Payne, Justin; Allard, Marc W; Hoffmann, Maria

    2016-01-01

    Salmonella enterica spp. are pathogenic bacteria commonly associated with food-borne outbreaks in human and animals. Salmonella enterica spp. are characterized into more than 2,500 different serotypes, which makes epidemiological surveillance and outbreak control more difficult. In this report, we announce the first complete genome and methylome sequences from two Salmonella type strains associated with food-borne outbreaks, Salmonella enterica subsp. enterica serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica serovar Sloterdijk (ATCC 15791). PMID:26988049

  5. Prevention of Salmonella contamination of finished soybean meal used for animal feed by a Norwegian production plant despite frequent Salmonella contamination of raw soy beans, 1994–2012

    OpenAIRE

    Wierup, Martin; Kristoffersen, Thor

    2014-01-01

    Background Salmonella contaminated animal feed is a major source for introducing Salmonella into the animal derived food chain. Because soybeans frequently are contaminated with Salmonella, soybean meal used as animal feed material, a by-product of a “crushing plant” which produces oil from soybeans, can be important source of Salmonella in the animal feed. We report the successful control of Salmonella from 1994 to 2012 in a Norwegian crushing plant producing soybean meal from imported soy b...

  6. Faecal Salmonella shedding in fattening pigs in relation to the presence of Salmonella antibodies in three pig production systems

    DEFF Research Database (Denmark)

    Bonde, Marianne Kjær; Sørensen, Jan Tind

    2012-01-01

    Human salmonellosis originating from pork is an important zoonotic disease, and the production of outdoor pigs may increase the risk of contaminating the food chain with Salmonella from environmental sources. The prevalence of faecal Salmonella shedding has therefore been compared in organic...... was 5.4% with no significant differences between systems. Pigs with Salmonella shedding on farm were more likely to also be shedding Salmonella at slaughter (P<0.001). The serological test result was a significant predictor of Salmonella shedding at slaughter in indi-vidual pigs from conventional......, conventional outdoor and indoor finishing pig herds in a Danish survey with participation of 34 herds. Individual faecal samples were collected from 30 to 50 pigs per herd before and after transport to slaughter and analysed for the presence of Salmonella. Further meat juice samples were collected from the...

  7. 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)

    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

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

    DEFF Research Database (Denmark)

    Refsum, T.; Handeland, K.; Baggesen, Dorte Lau; Holstad, G.; Kapperud, G.

    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 gulls......, 5 waterfowl, 4 birds of prey, 3 doves, and 2 crows. The bullfinch (Pyrrhula pyrrhula) was by far the most frequently recorded species (54% of the cases). Salmonella enterica serover Typhimurium was recovered from all cases except from one hooded crow (Corpus corone), which yielded serovar Paratyphi...

  9. 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.

  10. Prevalence of Nontyphoidal Salmonella and Salmonella Strains with Conjugative Antimicrobial-Resistant Serovars Contaminating Animal Feed in Texas.

    Science.gov (United States)

    Hsieh, Yi-Cheng; Poole, Toni L; Runyon, Mick; Hume, Michael; Herrman, Timothy J

    2016-02-01

    The objective of this study was to characterize 365 nontyphoidal Salmonella enterica isolates from animal feed. Among the 365 isolates, 78 serovars were identified. Twenty-four isolates (7.0%) were recovered from three of six medicated feed types. Three of these isolates derived from the medicated feed, Salmonella Newport, Salmonella Typhimurium var. O 5- (Copenhagen), and Salmonella Lexington var. 15+ (Manila), displayed antimicrobial resistance. Susceptibility testing revealed that only 3.0% (12) of the 365 isolates displayed resistance to any of the antimicrobial agents. These 12 isolates were recovered from unmedicated dry beef feed (n = 3), medicated dry beef feed (n = 3), cabbage culls (n = 2), animal protein products (n = 2), dry dairy cattle feed (n = 1), and fish meal (n = 1). Only Salmonella Newport and Salmonella Typhimurium var. O 5- (Copenhagen) were multidrug resistant. Both isolates possessed the IncA/C replicon and the blaCMY-2 gene associated with cephalosporin resistance. Plasmid replicons were amplified from 4 of 12 resistant isolates. Plasmids (40 kb) were Salmonella Montevideo and Salmonella Kentucky. Conjugation experiments were done using 7 of the 12 resistant isolates as donors. Only Salmonella Montevideo, possessing a plasmid and amplifying IncN, produced transconjugants. Transconjugants displayed the same antimicrobial resistance profile as did the donor isolate. Three isolates that amplified replicons corresponding to IncA/C or IncHI2 did not produce transconjugants at 30 or 37°C. The results of this study suggest that the prevalence of antimicrobial-resistant Salmonella contaminating animal feed is low in Texas. However, Salmonella was more prevalent in feed by-products; fish meal had the highest prevalence (84%) followed by animal protein products (48%). Ten of the 35 feed types had no Salmonella contamination. Further investigation is needed to understand the possible role of specific feed types in the dissemination of antimicrobial

  11. Attenuated aroA Salmonella enterica serovar Typhimurium does not induce inflammatory

    Czech Academy of Sciences Publication Activity Database

    Trebichavský, Ilja; Šplíchalová, Alla; Rychlík, I.; Hojná, Hana; Muneta, Y.; Mori, Y.; Šplíchal, Igor

    2006-01-01

    Roč. 24, - (2006), s. 4285-4289. ISSN 0264-410X R&D Projects: GA ČR GA524/05/2248 Institutional research plan: CEZ:AV0Z50200510 Keywords : gnotobiotic pig * aroa * cytokine Subject RIV: EE - Microbiology, Virology Impact factor: 3.159, year: 2006

  12. Oral vaccination with inhibin DNA delivered using attenuated Salmonella choleraesuis for improving reproductive traits in mice.

    Science.gov (United States)

    Han, Li; Zhen, Yan-Hong; Liang, Ai-Xin; Zhang, Jian; Riaz, Hasan; Xiong, Jia-Jun; Guo, Ai-Zhen; Yang, Li-Guo

    2014-09-01

    The objective of this study was to examine the efficacy and safety of a novel inhibin vaccine containing inhibin α (1-32) fragments in mice. A recombinant plasmid pVAX-asd-IS was constructed by inserting recombinant inhibin α (1-32) and the hepatitis B surface antigen S into the plasmid in which the asd gene, rather than the kanamycin gene, was a selection marker. Ninety Kuming mice were divided into six groups consisting of 15 mice each. First group was (C1) injected with 200 µl of PBS, second (C2) received 1 × 10(10) CFU of crp(-) /asd(-) C500/pVAX-asd and served as vector control, third did not receive any treatment (C3), while fourth, fifth, and sixth group received 1 × 10(10) , 1 × 10(9) , 1 × 10(8) CFU of the recombinant inhibin vaccine crp(-) /asd(-) C500/pVAX-asd-IS (group T1, T2, T3), respectively. Western blotting demonstrated that recombinant expressed inhibin protein possessed immune function and that this plasmid could replicate for up to 40 generations stably. Vaccination with this strain at a dose of 1 × 10(10) CFU/200 µl per mouse induced high anti-inhibin antibody levels, significantly increased large-follicle production in T1 group (p  0.05) compared with control groups. Integration studies showed no evidence of inhibin fusion gene integrated into mice's genome 2-month after immunization. These results suggest that the vaccine described in the present study may provide a safe method to improve reproductive traits in animals. A trend towards increased litter size and significant increase in large follicle population depict that this vaccine may have direct application in large animal industry. PMID:24123188

  13. Psoralen photomutagenic specificity in Salmonella typhimurium

    International Nuclear Information System (INIS)

    The cytotoxic and mutagenic specificity of two therapeutically employed psoralens was examined in several Ames Salmonella typhimurium strains with near ultraviolet light activation. Photomutagenic activity of 8-methoxypsoralen (8MOP) and 4,5',8-trimethylpsoralen (TMP) was found to be sequence-specific, and additionally was dependent on the level of DNA-repair proficiency. Phototoxicity was essentially identical in hisC3076, hisD3052 and hisG46 strains; uvrB- excision-repair-deficient bacteria were considerably more susceptible to lethal effects than wild-type parental strains. Finally, the data show that psoralens are potent frameshift photomutagens in Salmonella hisC3076 strains and demonstrate the potential utility of these strains in evaluating photomutagenic and phototoxic activity of new furocoumarin derivatives. (Auth.)

  14. Renal abscess caused by Salmonella Typhi

    Directory of Open Access Journals (Sweden)

    Amarjeet Kaur

    2015-01-01

    Full Text Available Salmonella typhi is a true pathogen, which is capable of causing both intestinal and extraintestinal infections. Unusual presentations of Salmonella should always be kept in mind as this organism can cause disease in almost any organ of the body. S. typhi has been reported to cause the life-threatening infections such as meningitis, endocarditis, myocarditis, empyema, and hepatic abscess. Renal involvement by S. typhi is a relatively rare presentation. We report a case of renal abscess caused by S. typhi in an afebrile, 10-year-old child who did not have any clinical history of enteric fever. To our knowledge, this is the first reported case of isolation of S. typhi from the renal abscess, and interestingly this isolate was found to be resistant to quinolones.

  15. Salmonella Dublin kan give store tab

    DEFF Research Database (Denmark)

    Nielsen, Torben Dahl; Nielsen, Liza Rosenbaum; Kudahl, Anne Margrethe Braad; Østergaard, Søren; Krogh, Kaspar

    Store besætninger lider størst økonomisk tab ved infektion med Salmonella Dublin. Selv i en veldrevet besætning kan tabet løbe op i mellem 1,3 og 3,3 millioner kr. over en tiårs periode. Ved uhensigtsmæssige hygiejne- og managementrutiner kan tabet nemt blive meget højere.......Store besætninger lider størst økonomisk tab ved infektion med Salmonella Dublin. Selv i en veldrevet besætning kan tabet løbe op i mellem 1,3 og 3,3 millioner kr. over en tiårs periode. Ved uhensigtsmæssige hygiejne- og managementrutiner kan tabet nemt blive meget højere....

  16. The Salmonella enterica Pan-genome

    DEFF Research Database (Denmark)

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

    2011-01-01

    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......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...... complete and 23 draft genome sequences). Of these, 35 were found to be of sufficiently good quality to allow a detailed analysis, along with two Escherichia coli strains (K-12 substr. DH10B and the avian pathogenic E. coli (APEC O1) strain). All genomes were subjected to standardized gene finding...

  17. Cholestatic hepatitis due to Salmonella typhi

    Directory of Open Access Journals (Sweden)

    Ayse Albayrak

    2011-04-01

    Full Text Available Salmonella infection occurs worldwide and is still an important public health problem in many developing countries. The infection can affect almost all major organs including the liver. Severe hepatic involvement with a clinical feature of acute hepatitis is a rare complication. In this paper, a 39-year-old male with acute cholestatic typhoid hepatitis is presented. The case had a tender hepatomegaly and elevated serum alanine and aspartate transaminase, alkaline phosphatase, and gamma glutamyl transferase levels; these features cannot been distinguished from those of acute viral hepatitis. Serological and viral markers of acute viral hepatitis were negative. No pathology could be determined in abdomen Ultrasonography (USG or Magnetic Reso - nance (MR Cholangiography. As enteric fever is a common infection, the recognition of salmonella hepatitis is of clinical importance. When patients from an endemic or outbreak area present acute febrile hepatitis, typhoid fever should be a consideration.

  18. Whole Genome Epidemiological Typing of Salmonella

    DEFF Research Database (Denmark)

    Leekitcharoenphon, Pimlapas

    . Technological advances and effective price in high throughput genome sequencing are making whole genome sequencing (WGS) available as a routine tool for bacterial typing. Typing of Salmonella, especially sub-typing within the same serotype or even the same clone, the genetic variation of the target genes being...... used for typing is crucial for successful discrimination. The core genes or the genes that are conserved in all members of a genus or species are potentially good candidates for investigating genomic variation in phylogeny and epidemiology. A total of 2,882 core genes have been observed among 73...... available Salmonella enterica genomes (accessed in April 2011). A consensus tree based on variation of the core genes gives better resolution than 16S rRNA and MLST that rarely provide separation between closely related strains. The performance of the pan-genome tree which is based on the presence...

  19. Seismic attenuation in fractured media

    International Nuclear Information System (INIS)

    The prime objective of this paper is to quantitatively estimate seismic attenuation caused by fractures with different physical parameters. In seismic wave simulation, the fractured media are treated as the anisotropic media and fractures are represented by frequency-dependent elastic constants. Based on numerical experiments with three different parameters, namely viscosity, porosity and the Lamé parameters, this paper has the following observations. First, seismic attenuation is not affected by the viscosity within fractures, although it increases with the increase of porosity and decreases with the increase of the Lamé parameters within fractures. Among the latter two parameters, seismic attenuation is more sensitive to the Lamé parameters than to the porosity. Second, for the attenuation anisotropy, low frequencies have more anisotropic effect than high frequencies. For example, a 50 Hz wavefield has the strongest anisotropy effect if compared to 100 and 150 Hz wavefields. The attenuation anisotropy for low frequency (say 50 Hz) is more sensitive to the viscosity than the porosity and the Lamé parameters have the weakest effect among these three parameters. These observations suggest that low-frequency seismic attenuation, and especially the attenuation anisotropy in low frequency, would have great potential for fluid discrimination within fractured media. (paper)

  20. Veterinary surgeons as vectors of Salmonella dublin.

    OpenAIRE

    Williams, E

    1980-01-01

    Salmonella dublin is an important bovine pathogen, causing dysentery, abortion, and death from septicaemia. S dublin dermatitis, a little-recognised occupational hazard for veterinary surgeons, does not cause serious disability or inconvenience. During a survey of brucellosis in south-west Wales four cases of S dublin dermatitis were seen in veterinary surgeons. One surgeon was reinfected three years later. On all five occasions the veterinary surgeons had not worn or had discarded polyethyle...

  1. lac Repressor Is an Antivirulence Factor of Salmonella enterica: Its Role in the Evolution of Virulence in Salmonella

    OpenAIRE

    Sandeepa M Eswarappa; Karnam, Guruswamy; Nagarajan, Arvindhan G; Chakraborty, Sangeeta; Chakravortty, Dipshikha

    2009-01-01

    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 e...

  2. Metabolic engineering of Salmonella vaccine bacteria to boost human Vγ2Vδ2 T cell immunity.

    Science.gov (United States)

    Workalemahu, Grefachew; Wang, Hong; Puan, Kia-Joo; Nada, Mohanad H; Kuzuyama, Tomohisa; Jones, Bradley D; Jin, Chenggang; Morita, Craig T

    2014-07-15

    Human Vγ2Vδ2 T cells monitor isoprenoid metabolism by recognizing foreign (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), a metabolite in the 2-C-methyl-D-erythritol-4-phosphate pathway used by most eubacteria and apicomplexan parasites, and self isopentenyl pyrophosphate, a metabolite in the mevalonate pathway used by humans. Whereas microbial infections elicit prolonged expansion of memory Vγ2Vδ2 T cells, immunization with prenyl pyrophosphates or aminobisphosphonates elicit short-term Vγ2Vδ2 expansion with rapid anergy and deletion upon subsequent immunizations. We hypothesized that a live, attenuated bacterial vaccine that overproduces HMBPP would elicit long-lasting Vγ2Vδ2 T cell immunity by mimicking a natural infection. Therefore, we metabolically engineered the avirulent aroA(-) Salmonella enterica serovar Typhimurium SL7207 strain by deleting the gene for LytB (the downstream enzyme from HMBPP) and functionally complementing for this loss with genes encoding mevalonate pathway enzymes. LytB(-) Salmonella SL7207 had high HMBPP levels, infected human cells as efficiently as did the wild-type bacteria, and stimulated large ex vivo expansions of Vγ2Vδ2 T cells from human donors. Importantly, vaccination of a rhesus monkey with live lytB(-) Salmonella SL7207 stimulated a prolonged expansion of Vγ2Vδ2 T cells without significant side effects or anergy induction. These studies provide proof-of-principle that metabolic engineering can be used to derive live bacterial vaccines that boost Vγ2Vδ2 T cell immunity. Similar engineering of metabolic pathways to produce lipid Ags or B vitamin metabolite Ags could be used to derive live bacterial vaccine for other unconventional T cells that recognize nonpeptide Ags. PMID:24943221

  3. 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.

  4. Immune reaction and survivability of salmonella typhimurium and salmonella infantis after infection of primary avian macrophages.

    Science.gov (United States)

    Braukmann, Maria; Methner, Ulrich; Berndt, Angela

    2015-01-01

    Salmonella serovars are differentially able to infect chickens. The underlying causes are not yet fully understood. Aim of the present study was to elucidate the importance of Salmonella Pathogenicity Island 1 and 2 (SPI-1 and -2) for the virulence of two non-host-specific, but in-vivo differently invasive, Salmonella serovars in conjunction with the immune reaction of the host. Primary avian splenic macrophages were inoculated with Salmonella enterica sub-species enterica serovar (S.) Typhimurium and S. Infantis. The number and viability of intracellular bacteria and transcription of SPI-1 and -2 genes by the pathogens, as well as transcription of immune-related proteins, surface antigen expression and nitric oxide production by the macrophages, were compared at different times post inoculation. After infection, both of the Salmonella serovars were found inside the primary macrophages. Invasion-associated SPI-1 genes were significantly higher transcribed in S. Infantis- than S. Typhimurium-infected macrophages. The macrophages counteracted the S. Infantis and S. Typhimurium infection with elevated mRNA expression of inducible nitric oxide synthase (iNOS), interleukin (IL)-12, IL-18 and lipopolysaccharide-induced tumor necrosis factor alpha factor (LITAF) as well as with an increased synthesis of nitric oxide. Despite these host cell attacks, S. Typhimurium was better able than S. Infantis to survive within the macrophages and transcribed higher rates of the SPI-2 genes spiC, ssaV, sifA, and sseA. The results showed similar immune reactions of primary macrophages after infection with both of the Salmonella strains. The more rapid and stronger transcription of SPI-2-related genes by intracellular S. Typhimurium compared to S. Infantis might be responsible for its better survival in avian primary macrophages. PMID:25811871

  5. Immune reaction and survivability of salmonella typhimurium and salmonella infantis after infection of primary avian macrophages.

    Directory of Open Access Journals (Sweden)

    Maria Braukmann

    Full Text Available Salmonella serovars are differentially able to infect chickens. The underlying causes are not yet fully understood. Aim of the present study was to elucidate the importance of Salmonella Pathogenicity Island 1 and 2 (SPI-1 and -2 for the virulence of two non-host-specific, but in-vivo differently invasive, Salmonella serovars in conjunction with the immune reaction of the host. Primary avian splenic macrophages were inoculated with Salmonella enterica sub-species enterica serovar (S. Typhimurium and S. Infantis. The number and viability of intracellular bacteria and transcription of SPI-1 and -2 genes by the pathogens, as well as transcription of immune-related proteins, surface antigen expression and nitric oxide production by the macrophages, were compared at different times post inoculation. After infection, both of the Salmonella serovars were found inside the primary macrophages. Invasion-associated SPI-1 genes were significantly higher transcribed in S. Infantis- than S. Typhimurium-infected macrophages. The macrophages counteracted the S. Infantis and S. Typhimurium infection with elevated mRNA expression of inducible nitric oxide synthase (iNOS, interleukin (IL-12, IL-18 and lipopolysaccharide-induced tumor necrosis factor alpha factor (LITAF as well as with an increased synthesis of nitric oxide. Despite these host cell attacks, S. Typhimurium was better able than S. Infantis to survive within the macrophages and transcribed higher rates of the SPI-2 genes spiC, ssaV, sifA, and sseA. The results showed similar immune reactions of primary macrophages after infection with both of the Salmonella strains. The more rapid and stronger transcription of SPI-2-related genes by intracellular S. Typhimurium compared to S. Infantis might be responsible for its better survival in avian primary macrophages.

  6. Electrochemical immunosensors for Salmonella detection in food.

    Science.gov (United States)

    Melo, Airis Maria Araújo; Alexandre, Dalila L; Furtado, Roselayne F; Borges, Maria F; Figueiredo, Evânia Altina T; Biswas, Atanu; Cheng, Huai N; Alves, Carlúcio R

    2016-06-01

    Pathogen detection is a critical point for the identification and the prevention of problems related to food safety. Failures at detecting contaminations in food may cause outbreaks with drastic consequences to public health. In spite of the real need for obtaining analytical results in the shortest time possible, conventional methods may take several days to produce a diagnosis. Salmonella spp. is the major cause of foodborne diseases worldwide and its absence is a requirement of the health authorities. Biosensors are bioelectronic devices, comprising bioreceptor molecules and transducer elements, able to detect analytes (chemical and/or biological species) rapidly and quantitatively. Electrochemical immunosensors use antibody molecules as bioreceptors and an electrochemical transducer. These devices have been widely used for pathogen detection at low cost. There are four main techniques for electrochemical immunosensors: amperometric, impedimetric, conductometric, and potentiometric. Almost all types of immunosensors are applicable to Salmonella detection. This article reviews the developments and the applications of electrochemical immunosensors for Salmonella detection, particularly the advantages of each specific technique. Immunosensors serve as exciting alternatives to conventional methods, allowing "real-time" and multiple analyses that are essential characteristics for pathogen detection and much desired in health and safety control in the food industry. PMID:27138197

  7. The Base Excision Repair system of Salmonella enterica serovar typhimurium counteracts DNA damage by host nitric oxide.

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    Anthony R Richardson

    2009-05-01

    Full Text Available Intracellular pathogens must withstand nitric oxide (NO. generated by host phagocytes. Salmonella enterica serovar Typhimurium interferes with intracellular trafficking of inducible nitric oxide synthase (iNOS and possesses multiple systems to detoxify NO.. Consequently, the level of NO. stress encountered by S. Typhimurium during infection in vivo has been unknown. The Base Excision Repair (BER system recognizes and repairs damaged DNA bases including cytosine and guanine residues modified by reactive nitrogen species. Apurinic/apyrimidinic (AP sites generated by BER glycosylases require subsequent processing by AP endonucleases. S. Typhimurium xth nfo mutants lacking AP endonuclease activity exhibit increased NO. sensitivity resulting from chromosomal fragmentation at unprocessed AP sites. BER mutant strains were thus used to probe the nature and extent of nitrosative damage sustained by intracellular bacteria during infection. Here we show that an xth nfo S. Typhimurium mutant is attenuated for virulence in C3H/HeN mice, and virulence can be completely restored by the iNOS inhibitor L-NIL. Inactivation of the ung or fpg glycosylase genes partially restores virulence to xth nfo mutant S. Typhimurium, demonstrating that NO. fluxes in vivo are sufficient to modify cytosine and guanine bases, respectively. Mutants lacking ung or fpg exhibit NO.-dependent hypermutability during infection, underscoring the importance of BER in protecting Salmonella from the genotoxic effects of host NO.. These observations demonstrate that host-derived NO. damages Salmonella DNA in vivo, and the BER system is required to maintain bacterial genomic integrity.

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

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    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.

  9. Salmonella Pathogenicity Island 2 Influences Both Systemic Salmonellosis and Salmonella-Induced Enteritis in Calves

    OpenAIRE

    Bispham, J; B.N Tripathi; Watson, P. R.; Wallis, T S

    2001-01-01

    We have used signature-tagged mutagenesis to identify mutants of the host-specific Salmonella enterica serotype Dublin which were avirulent in calves and/or BALB/c mice. A mutant with a transposon insertion in the sseD gene of Salmonella pathogenicity island 2 (SPI-2), which encodes a putative secreted effector protein, was identified. This mutant was recovered from the bovine host but not from the murine host following infection with a pool of serotype Dublin mutants. However, a pure inoculu...

  10. Study of Salmonella Typhimurium Infection in Laying Hens

    Science.gov (United States)

    Pande, Vivek V.; Devon, Rebecca L.; Sharma, Pardeep; McWhorter, Andrea R.; Chousalkar, Kapil K.

    2016-01-01

    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 colonize 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 colonize 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% S. Typhimurium, 14.1% S. 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 time

  11. 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

  12. Diversity of Salmonella Isolates from Central Florida Surface Waters

    Science.gov (United States)

    McEgan, Rachel; Chandler, Jeffrey C.; Goodridge, Lawrence D.

    2014-01-01

    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

  13. 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. PMID:24680076

  14. The engineered Salmonella typhimurium inhibits tumorigenesis in advanced glioma

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    Chen JQ

    2015-09-01

    Full Text Available Jian-qiang Chen,1 Yue-fu Zhan,2 Wei Wang,1 Sheng-nan Jiang,2,3 Xiang-ying Li21Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, People’s Republic of China; 2Department of Radiology, Affiliated to Haikou Hospital Xiangya School of Medicine, Central South University, Haikou, People’s Republic of China; 3Department of Nuclear Medicine, Central South University Xiangya School of Medicine Affiliated HaiKou Hospital, Haikou, Hainan, People’s Republic of ChinaObjective: To explore the antitumor role of the attenuated Salmonella typhimurium ΔppGpp with inducible cytolysin A (ClyA in advanced stage of glioma.Materials and methods: The C6 rat glioma cells were orthotopically implanted by surgery into the caudate nucleus of rat brains. The rats were then randomly divided into the treatment group (SL + ClyA (n=12, negative control group (SL (n=12, and control group (phosphate-buffered saline [PBS] (n=12. In the treatment group, the attenuated S. typhimurium were transformed with the plasmid-encoded antitumor gene ClyA. The expression of ClyA was controlled by the TetR-regulated promoter in response to extracellular doxycycline. The plasmid also contained an imaging gene lux to allow illumination of the tumor infected by the bacteria. The rat glioma C6 cells were implanted into the caudate nucleus of all rats. The engineered S. typhimurium and respective controls were injected intravenously into the rats 21 days after initial tumor implantation. The pathological analysis of the glioma tumor was performed at 21 days and 28 days (7 days after doxycycline treatment postimplantation. All rats underwent MRI (magnetic resonance imaging and bioluminescence study at 21 days and 28 days postimplantation to detect tumor volume. The differences between the three groups in tumor volume and survival time were analyzed.Results: Advanced stage glioma  was detected at 21 days postimplantation. Bioluminescence showed that the

  15. An oral recombinant Salmonella enterica serovar Typhimurium mutant elicits systemic antigen-specific CD8+ T cell cytokine responses in mice

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    Chin'ombe Nyasha

    2009-04-01

    Full Text Available Abstract Background The induction of antigen-specific CD8+ T cell cytokine responses against an attenuated, oral recombinant Salmonella enterica serovar Typhimurium vaccine expressing a green fluorescent protein (GFP model antigen was investigated. A GFP expression plasmid was constructed in which the gfp gene was fused in-frame with the 5' domain of the Escherichia coli β-galactosidase α-gene fragment with expression under the lac promoter. Groups of mice were orally immunized three times with the bacteria and systemic CD8+ T cell cytokine responses were evaluated. Results High level of the GFP model antigen was expressed by the recombinant Salmonella vaccine vector. Systemic GFP-specific CD8+ T cell cytokine (IFN-γ and IL-4 immune responses were detected after mice were orally vaccinated with the bacteria. It was shown that 226 net IFN-γ and 132 net IL-4 GFP-specific SFUs/10e6 splenocytes were formed in an ELISPOT assay. The level of IFN-γ produced by GFP peptide-stimulated cells was 65.2-fold above background (p Conclusion These results suggested that a high expressing recombinant Salmonella vaccine given orally to mice would elicit antigen-specific CD8+ T cell responses in the spleen. Salmonella bacteria may, therefore, be used as potential mucosal vaccine vectors.

  16. Transmission and shedding patterns of Salmonella in naturally infected captive wild roof rats (Rattus rattus) from a Salmonella-contaminated layer farm.

    Science.gov (United States)

    Umali, Dennis V; Lapuz, Randy Rhon Simoun P; Suzuki, Terumasa; Shirota, Kazutoshi; Katoh, Hiromitsu

    2012-06-01

    Rodents play a major role in the transmission and maintenance of Salmonella contamination cycles in poultry facilities. However, very limited field data are available regarding the transmission routes, infection cycle, and shedding patterns of Salmonella by naturally infected wild rodents from commercial layer farms. In this study, a total of 128 resident wild roof rats (Rattus ratus) were captured from a Salmonella-contaminated layer facility. All roof rats were divided into 51 laboratory cages, and weekly monitoring of Salmonella fecal shedding patterns was conducted for 53 wk. Seven roof rats from cages that were observed to frequently shed Salmonella were isolated in individual cages, and daily Salmonella monitoring was performed for 35 days. At the end of monitoring, each roof rat was euthanatized, and isolation of Salmonella from different organs was performed. Results of weekly monitoring of Salmonella showed that 21 of 51 cages (41.2%) were positive for Salmonella Infantis, while two cages (3.92%) were positive for Salmonella Enteritidis. Moreover, 11 cages were positive for Salmonella for at least two sampling weeks. Isolation of Salmonella from fecal droppings was mainly observed during the first 12 wk of captivity. The longest interval between two Salmonella-positive fecal dropping was 24 wk. In the daily Salmonella monitoring, only Salmonella Infantis was isolated from fecal droppings, in which the highest number of Salmonella Infantis organisms per fecal dropping was at 1 x 10(8) colony-forming units (cfu), while the lowest measured quantity was 1 x 10(3) cfu. It was noted that the frequency of Salmonella shedding in fecal droppings appeared to have a linear correlation (r = 0.85) with the number of Salmonella organisms (cfu) per fecal pellet (P poultry facilities through intermittent fecal shedding. Moreover, Salmonella Enteritidis in wild roof rats appears to be more of a systemic infection, in which isolation is most likely to occur in internal

  17. Towards a human oral vaccine for anthrax: the utility of a Salmonella Typhi Ty21a-based prime-boost immunization strategy.

    Science.gov (United States)

    Baillie, Leslie W J; Rodriguez, Ana L; Moore, Stephen; Atkins, Helen S; Feng, Chiguang; Nataro, James P; Pasetti, Marcela F

    2008-11-11

    We previously demonstrated the ability of an orally administered attenuated Salmonella enterica serovar Typhimurium strain expressing the protective antigen (PA) of Bacillus anthracis to confer protection against lethal anthrax aerosol spore challenge [Stokes MG, Titball RW, Neeson BN, et al. Oral administration of a Salmonella enterica-based vaccine expressing Bacillus anthracis protective antigen confers protection against aerosolized B. anthracis. Infect Immun 2007;75(April (4)):1827-34]. To extend the utility of this approach to humans we constructed variants of S. enterica serovar Typhi Ty21a, an attenuated typhoid vaccine strain licensed for human use, which expressed and exported PA via two distinct plasmid-based transport systems: the Escherichia coli HlyA haemolysin and the S. Typhi ClyA export apparatus. Murine immunogenicity studies confirmed the ability of these constructs, especially Ty21a expressing the ClyA-PA fusion protein, to stimulate strong PA-specific immune responses following intranasal immunization. These responses were further enhanced by a subsequent boost with either parenterally delivered recombinant PA or the licensed US human alum-adsorbed anthrax vaccine (AVA). Anthrax toxin neutralizing antibody responses using this prime-boost regimen were rapid, vigorous and broad in nature. The results of this study demonstrate the feasibility of employing a mucosal prime with a licensed Salmonella Typhi vaccine strain followed by a parenteral protein boost to stimulate rapid protective immunity against anthrax. PMID:18805452

  18. Genetic mapping of the Salmonella typhimurium pepB locus.

    OpenAIRE

    Green, L; Miller, C G

    1980-01-01

    Transposon technology has been used to map the pepB locus of Salmonella typhimurium. This locus is cotransducible by phage P22 with glyA and strB at min 56 on the Salmonella genetic map. The gene order is strB pepB glyA.

  19. Evaluation of gallium maltolate on fecal Salmonella shedding in cattle

    Science.gov (United States)

    Salmonella is a major cause of foodborne illness in humans and causes over a third of all cases of gastroenteritis in the United States. Human foodborne outbreaks due to Salmonella have been traced to milk, beef, pork, and poultry. Fecal contamination of the carcass and hide is thought to be a maj...

  20. 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...

  1. Differences in attachment of Salmonella to fresh produce

    Science.gov (United States)

    Salmonella outbreaks have been associated with the consumption of fresh produce. The produce may be contaminated with Salmonella at any point throughout the food continuum. To develop effective strategies to minimize the risk of foodborne disease caused by this organism, it is essential to examine i...

  2. 21 CFR 118.4 - Salmonella Enteritidis (SE) prevention measures.

    Science.gov (United States)

    2010-04-01

    ... National Poultry Improvement Plan's standards for “U.S. S. Enteritidis Clean” status (9 CFR 145.23(d)) or... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Salmonella Enteritidis (SE) prevention measures....4 Salmonella Enteritidis (SE) prevention measures. You must follow the SE prevention measures...

  3. Overview of USDA VetNet Salmonella Database

    Science.gov (United States)

    USDA VetNet commenced in May 2004 with submission of Salmonella isolates and in December 2005, Campylobacter isolates were added to the program. The objectives of USDA VetNet are to determine PFGE patterns of Salmonella and Campylobacter isolates submitted to the National Antimicrobial Resistance Mo...

  4. 75 FR 48973 - Draft Guidance for Industry: Prevention of Salmonella

    Science.gov (United States)

    2010-08-12

    ...-1493. SUPPLEMENTARY INFORMATION: I. Background In the Federal Register of July 9, 2009 (74 FR 33030... HUMAN SERVICES Food and Drug Administration Draft Guidance for Industry: Prevention of Salmonella... availability of a draft guidance entitled ``Prevention of Salmonella Enteritidis in Shell Eggs...

  5. TOE ABSCESS WITH SALMONELLA TYPHIMURIUM IN SICKLE CELL ANEMIA PATIENT

    Directory of Open Access Journals (Sweden)

    A. Rangaiahagari

    2014-06-01

    Full Text Available Salmonella are a rare cause of toe abscess. We report a case of Salmonella typhimurium in sickle cell anemia in a pediatric patient. The isolate was sensitive to commonly used antibiotics and the patient was treated successfully with a course of amoxicillin.

  6. Development of bioluminescent Salmonella strains for use in food safety

    Directory of Open Access Journals (Sweden)

    Bailey R Hartford

    2008-01-01

    Full Text Available Abstract Background Salmonella can reside in healthy animals without the manifestation of any adverse effects on the carrier. If raw products of animal origin are not handled properly during processing or cooked to a proper temperature during preparation, salmonellosis can occur. In this research, we developed bioluminescent Salmonella strains that can be used for real-time monitoring of the pathogen's growth on food products. To accomplish this, twelve Salmonella strains from the broiler production continuum were transformed with the broad host range plasmid pAKlux1, and a chicken skin attachment model was developed. Results Salmonella strains carrying pAKlux1 constitutively expressed the luxCDABE operon and were therefore detectable using bioluminescence. Strains were characterized in terms of bioluminescence properties and plasmid stability. To assess the usefulness of bioluminescent Salmonella strains in food safety studies, we developed an attachment model using chicken skin. The effect of washing on attachment of Salmonella strains to chicken skin was tested using bioluminescent strains, which revealed the attachment properties of each strain. Conclusion This study demonstrated that bioluminescence is a sensitive and effective tool to detect Salmonella on food products in real-time. Bioluminescence imaging is a promising technology that can be utilized to evaluate new food safety measures for reducing Salmonella contamination on food products.

  7. Complete Genome of Salmonella enterica Serovar Enteritidis Myophage Marshall

    OpenAIRE

    Luna, Adrian J.; Wood, Thammajun L.; Chamakura, Karthik R.; Kuty Everett, Gabriel F.

    2013-01-01

    Salmonella enterica serovar Enteritidis is a food-borne pathogen that causes salmonellosis in the United States. Bacteriophages are emerging as viable biocontrol agents against this pathogen. Here, we present the complete annotated genome sequence of Salmonella Enteritidis T4-like myophage Marshall, which has potential as a phage therapy agent.

  8. Salmonella bacteriophage diversity reflects host diversity on dairy farms.

    Science.gov (United States)

    Switt, Andrea I Moreno; den Bakker, Henk C; Vongkamjan, Kitiya; Hoelzer, Karin; Warnick, Lorin D; Cummings, Kevin J; Wiedmann, Martin

    2013-12-01

    Salmonella is an animal and human pathogen of worldwide concern. Surveillance programs indicate that the incidence of Salmonella serovars fluctuates over time. While bacteriophages are likely to play a role in driving microbial diversity, our understanding of the ecology and diversity of Salmonella phages is limited. Here we report the isolation of Salmonella phages from manure samples from 13 dairy farms with a history of Salmonella presence. Salmonella phages were isolated from 10 of the 13 farms; overall 108 phage isolates were obtained on serovar Newport, Typhimurium, Dublin, Kentucky, Anatum, Mbandaka, and Cerro hosts. Host range characterization found that 51% of phage isolates had a narrow host range, while 49% showed a broad host range. The phage isolates represented 65 lysis profiles; genome size profiling of 94 phage isolates allowed for classification of phage isolates into 11 groups with subsequent restriction fragment length polymorphism analysis showing considerable variation within a given group. Our data not only show an abundance of diverse Salmonella phage isolates in dairy farms, but also show that phage isolates that lyse the most common serovars causing salmonellosis in cattle are frequently obtained, suggesting that phages may play an important role in the ecology of Salmonella on dairy farms. PMID:24010608

  9. Serotyping of Salmonella Isolates from Broiler Vertical Integrations in Colombia

    Science.gov (United States)

    This study analyzed 106 Salmonella isolates from different points in broiler vertical integrations of two important poultry areas of Colombia. It was possible to identify the presence of Salmonella in five categories: breeder farm (17.9%), hatchery (6.6 %), broiler farm (38.7 %), processing plant (9...

  10. Orange peel products can reduce Salmonella populations in ruminants

    Science.gov (United States)

    Salmonella can live undetected in the gut of food animals and be spread to humans directly and indirectly. Diet can impact intestinal populations of foodborne pathogens, including Salmonella spp. Orange juice production results in a waste product, orange peel and orange pulp, which has a high nutr...

  11. Split marketing: A risk factor for Salmonella in market pigs?

    Science.gov (United States)

    This study was designed to determine if split marketing affects Salmonella prevalence in market pigs, by comparing the Salmonella prevalence in the first group of pigs selected for slaughter (i.e., “First pull”) versus the last group of pigs selected for slaughter (i.e., “Close out”) from typical co...

  12. Salmonella enterica Strains with Reduced Susceptibility to Quarternary Ammonium Compounds

    Science.gov (United States)

    Background: Salmonella spp. are responsible for 76 million illnesses per year in the U.S. Quaternary ammonium compounds (QAC) are commonly used antimicrobial agents. Reduced susceptibility to these compounds by a broad spectrum of organisms is a concern. Methods: Salmonella enterica strains with r...

  13. Salmonella Source Attribution in Japan by a Microbiological Subtyping Approach

    DEFF Research Database (Denmark)

    Toyofuku, Hajime; Pires, Sara Monteiro; Hald, Tine

    In order to estimate the number of human Salmonella infections attributable to each of major animal-food source, and help identifying the best Salmonella intervention strategies, a microbial subtyping approach for source attribution was applied. We adapted a Bayesian model that attributes illness...

  14. Improved expression systems for regulated expression in Salmonella infecting eukaryotic cells.

    Science.gov (United States)

    Medina, Carlos; Camacho, Eva María; Flores, Amando; Mesa-Pereira, Beatriz; Santero, Eduardo

    2011-01-01

    In this work we describe a series of improvements to the Salmonella-based salicylate-inducible cascade expression system comprised of a plasmid-borne expression module, where target gene expression is driven by the P(m) promoter governed by the XylS2 regulator, and a genome-integrated regulatory module controlled by the nahR/P(sal) system. We have constructed a set of high and low-copy number plasmids bearing modified versions of the expression module with a more versatile multiple cloning site and different combinations of the following elements: (i) the nasF transcriptional attenuator, which reduces basal expression levels, (ii) a strong ribosome binding site, and (iii) the Type III Secretion System (TTSS) signal peptide from the effector protein SspH2 to deliver proteins directly to the eukaryotic cytosol following bacterial infection of animal cells. We show that different expression module versions can be used to direct a broad range of protein production levels. Furthermore, we demonstrate that the efficient reduction of basal expression by the nasF attenuator allows the cloning of genes encoding highly cytotoxic proteins such as colicin E3 even in the absence of its immunity protein. Additionally, we show that the Salmonella TTSS is able to translocate most of the protein produced by this regulatory cascade to the cytoplasm of infected HeLa cells. Our results indicate that these vectors represent useful tools for the regulated overproduction of heterologous proteins in bacterial culture or in animal cells, for the cloning and expression of genes encoding toxic proteins and for pathogenesis studies. PMID:21829692

  15. Improved expression systems for regulated expression in Salmonella infecting eukaryotic cells.

    Directory of Open Access Journals (Sweden)

    Carlos Medina

    Full Text Available In this work we describe a series of improvements to the Salmonella-based salicylate-inducible cascade expression system comprised of a plasmid-borne expression module, where target gene expression is driven by the P(m promoter governed by the XylS2 regulator, and a genome-integrated regulatory module controlled by the nahR/P(sal system. We have constructed a set of high and low-copy number plasmids bearing modified versions of the expression module with a more versatile multiple cloning site and different combinations of the following elements: (i the nasF transcriptional attenuator, which reduces basal expression levels, (ii a strong ribosome binding site, and (iii the Type III Secretion System (TTSS signal peptide from the effector protein SspH2 to deliver proteins directly to the eukaryotic cytosol following bacterial infection of animal cells. We show that different expression module versions can be used to direct a broad range of protein production levels. Furthermore, we demonstrate that the efficient reduction of basal expression by the nasF attenuator allows the cloning of genes encoding highly cytotoxic proteins such as colicin E3 even in the absence of its immunity protein. Additionally, we show that the Salmonella TTSS is able to translocate most of the protein produced by this regulatory cascade to the cytoplasm of infected HeLa cells. Our results indicate that these vectors represent useful tools for the regulated overproduction of heterologous proteins in bacterial culture or in animal cells, for the cloning and expression of genes encoding toxic proteins and for pathogenesis studies.

  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. Analysis of antimicrobial resistance and plasmid profiles in Salmonella serovars associated with tropical seafood of India.

    Science.gov (United States)

    Kumar, Rakesh; Surendran, P K; Thampuran, Nirmala

    2009-06-01

    A total of 256 Salmonella strains consisting of 29 Salmonella serovars isolated from seafood of Cochin (India) were analyzed for resistance to antimicrobials commonly used in human and veterinary medicines as therapeutic agents. The 10 most predominant Salmonella serovars in seafood were also characterized for presence of plasmids using the alkaline lysis method. Antimicrobial susceptibility studies highlighted a comparatively high resistance in Salmonella isolates to sulfamethizol and carbenicillin, and moderate resistance to nalidixic acid and oxytetracycline. Nevertheless, antimicrobial resistance was not observed against ampicillin, ciprofloxacin, chloramphenicol, gentamicin, and kanamycin in different Salmonella serovars. Fifty percent of the Salmonella isolates, comprising 16 Salmonella serovars, were resistant to sulfamethizol followed by 39% resistant to carbenicillin and 14% resistant to oxytetracycline. Multidrug resistance was detected in 39.4%, 14.4%, 12.1%, and 1.5% of Salmonella isolates towards two drugs (sulfamethizol and carbenicillin), three drugs (sulfamethizol, carbenicillin, and oxytetracycline), four drugs (sulfamethizol, carbenicillin, oxytetracycline, and nalidixic acid), and five drugs (sulfamethizol, carbenicillin, oxytetracycline, nalidixic acid, and streptomycin), respectively. Plasmid profiling highlighted the presence of nine plasmid profiles in Salmonella serovars and plasmids that were not detected in Salmonella enterica subsp. enterica Weltevreden, Salmonella Rissen, Salmonella Bareilly, Salmonella Irumu, Salmonella Ohio, Salmonella Oslo, and Salmonella Typhi isolated from seafood. PMID:19422307

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

    DEFF Research Database (Denmark)

    Skov, M. N.; Madsen, J. J.; Rahbek, C.; Lodal, J.; Jespersen, J. B.; Jørgensen, J. C.; Dietz, H. H.; Chriél, Mariann; Baggesen, Dorte Lau

    2008-01-01

    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...

  19. Evaluation of different analysis and identification methods for Salmonella detection in surface drinking water sources

    International Nuclear Information System (INIS)

    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.

  20. Bacterial antigen expression is an important component in inducing an immune response to orally administered Salmonella-delivered DNA vaccines.

    Directory of Open Access Journals (Sweden)

    Michelle E Gahan

    Full Text Available BACKGROUND: The use of Salmonella to deliver heterologous antigens from DNA vaccines is a well-accepted extension of the success of oral Salmonella vaccines in animal models. Attenuated S. typhimurium and S. typhi strains are safe and efficacious, and their use to deliver DNA vaccines combines the advantages of both vaccine approaches, while complementing the limitations of each technology. An important aspect of the basic biology of the Salmonella/DNA vaccine platform is the relative contributions of prokaryotic and eukaryotic expression in production of the vaccine antigen. Gene expression in DNA vaccines is commonly under the control of the eukaryotic cytomegalovirus (CMV promoter. The aim of this study was to identify and disable putative bacterial promoters within the CMV promoter and evaluate the immunogenicity of the resulting DNA vaccine delivered orally by S. typhimurium. METHODOLOGY/PRINCIPAL FINDINGS: The results reported here clearly demonstrate the presence of bacterial promoters within the CMV promoter. These promoters have homology to the bacterial consensus sequence and functional activity. To disable prokaryotic expression from the CMV promoter a series of genetic manipulations were performed to remove the two major bacterial promoters and add a bacteria transcription terminator downstream of the CMV promoter. S. typhimurium was used to immunise BALB/c mice orally with a DNA vaccine encoding the C-fragment of tetanus toxin (TT under control of the original or the modified CMV promoter. Although both promoters functioned equally well in eukaryotic cells, as indicated by equivalent immune responses following intramuscular delivery, only the original CMV promoter was able to induce an anti-TT specific response following oral delivery by S. typhimurium. CONCLUSIONS: These findings suggest that prokaryotic expression of the antigen and co-delivery of this protein by Salmonella are at least partially responsible for the successful

  1. Salmonella prevalence among reptiles in a Zoo education setting

    DEFF Research Database (Denmark)

    Hydeskov, H. B.; Guardabassi, Luca; Aalbæk, Bent;

    2013-01-01

    Clinically healthy reptiles may shed Salmonella and therefore act as a potential zoonotic threat. Most people in Northern European countries are rarely exposed to reptiles, but many zoos have education departments where children have direct contact with this group of animals. The objectives...... of this study were to determine the prevalence and serotype distribution of Salmonella among reptiles in the Education Department (n = 55) at Copenhagen Zoo and compare it to the Zoo's main reptile collection (n = 145) to evaluate the zoonotic risk. Salmonella was isolated from cloacal swabs by selective...... department to another was very limited indicated by the serotype distribution. Despite the relative high prevalence observed among the reptiles in the Zoo's Education Department compared to the reptiles in the Zoo's main reptile collection, no Salmonella cases have been linked to the Zoo, and Salmonella ser...

  2. 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. PMID:24560590

  3. 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.

  4. The immunological relationship between filtrable agent, Salmonella and murine leukosis

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    Hamazaki,Yukio

    1977-12-01

    Full Text Available Salmonella typhimurium was invariably isolated from our J strain murine leukosis. Immunization of D103 mice with either inactivated Salmonella typhimurium or the cell-free extract of leukosis inhibited the transplantation of leukosis. The adoptive immunization of D103 mice with spleen cells of Strong A mice immunized with either Salmonella or the cell-free extract of leukosis inhibited the transplantation of leukosis. The addition of either Salmonella or the cell-free extract of leukosis inhibited the migration of macrophages of leukosis spleen in tissue culture. Strong A mice is non-susceptible to J strain leukosis. However, inoculation of neonatal Strong A mice with the cell-free extract of leukosis produced a susceptibility to the transplantation of leukosis. These results suggest that both a filtrable agent and Salmonella typhimurium are present in cells of this leukosis and might be etiologically related to the leukosis.

  5. A Live Salmonella Gallinarum Vaccine Candidate Secreting an Adjuvant Protein Confers Enhanced Safety and Protection Against Fowl Typhoid.

    Science.gov (United States)

    Shafiq, Muhammad Hassan; Kamble, Nitin M; Kim, Tae Hoon; Choi, Yoonyoung; Lee, John Hwa

    2015-12-01

    Live attenuated vaccines are used for effective protection against fowl typhoid (FT) in domestic poultry. In this study, a lon/cpxR/asd deletion mutant of Salmonella Gallinarum expressing the B subunit of a heat labile toxin (LTB) from Escherichia coli, a known adjuvant, was cloned in a recombinant p15A ori plasmid, JOL1355, and evaluated as a vaccine candidate in chickens. The plasmid was shown to be stable inside the attenuated Salmonella Gallinarum cell after three successive generations. Moreover, from an environmental safety point of view, apart from day 1 the JOL1355 strain was not detected in feces through day 21 postinoculation. For the efficacy of JOL1355, a total of 100 chickens were equally divided into two groups. Group A (control) chickens were intramuscularly inoculated with phosphate-buffered saline at 4 and 8 wk of age. Group B chickens were primed and boosted via the intramuscular route with 200 μL of a bacterial suspension of JOL1355 containing 1 × 10(8) colony forming units. All the chickens in Group A and B were challenged at 3 wk postbooster by oral inoculation with a wild-type Salmonella Gallinarum strain, JOL420. The JOL1355-immunized group showed significant protection and survival against the virulent challenge compared to the nonimmunized group. In addition, Group B exhibited a significantly higher humoral immune response, and the chickens remained healthy without any symptoms of anorexia, diarrhea, or depression. Group B also exhibited a significantly lower mortality rate of 4% compared to the 46% of the control group, which can be attributed to higher immunogenicity and better protection. The Group B chickens had significantly lower lesion scores for affected organs, such as the liver and spleen, compared to those of the control chickens (P < 0.01). These findings suggest that JOL1355 is a promising candidate for a safe and highly immunogenic vaccine against FT. PMID:26629629

  6. Detection of Salmonella spp, Salmonella Enteritidis and Typhimurium in naturally infected broiler chickens by a multiplex PCR-based assay

    Science.gov (United States)

    Paião, F.G.; Arisitides, L.G.A.; Murate, L.S.; Vilas-Bôas, G.T.; Vilas-Boas, L.A.; Shimokomaki, M.

    2013-01-01

    The presence of Salmonella in the intestinal tract, on the chickens skin and among their feathers, may cause carcasses contamination during slaughtering and processing and possibly it is responsible by the introduction of this microorganism in the slaughterhouses. A rapid method to identify and monitor Salmonella and their sorovars in farm is becoming necessary. A pre-enriched multiplex polymerase chain reaction (m-PCR) assay employing specific primers was developed and used to detect Salmonella at the genus level and to identify the Salmonella enterica serovar Enteritidis (S. Enteritidis) and Salmonella enterica serovar Typhimurium (S. Typhimurium) in broiler chicken swab samples. The method was validated by testing DNA extract from 90 fresh culture cloacal swab samples from poultry chicken cultured in phosphate buffer peptone water at 37 °C for 18 h. The final results showed the presence of Salmonella spp. in 25% of samples, S. Enteritidis was present in 12% of the Salmonella-positive samples and S. Typhimurium in 3% of the samples. The m-PCR assay developed in this study is a specific and rapid alternative method for the identification of Salmonella spp. and allowed the observation of specific serovar contamination in the field conditions within the locations where these chickens are typically raised. PMID:24159281

  7. Presence of Salmonella Enteritidis and Salmonella Gallinarum in commercial laying hens diagnosed with Fowl Typhoid Disease in Colombia

    Science.gov (United States)

    : A severe outbreak of salmonellosis in commercial brown table egg layers first occurred in Colombia in 2006. From 2008 to 2012, 35 samples collected from commercial layers farms in the states of Cundinamarca, Santander, Bolivar and San Andres, were positive to Salmonella enterica. Salmonella (S) wa...

  8. Meta-analysis of Chicken – Salmonella infection experiments

    Directory of Open Access Journals (Sweden)

    te Pas Marinus FW

    2012-04-01

    Full Text Available Abstract Background Chicken meat and eggs can be a source of human zoonotic pathogens, especially Salmonella species. These food items contain a potential hazard for humans. Chickens lines differ in susceptibility for Salmonella and can harbor Salmonella pathogens without showing clinical signs of illness. Many investigations including genomic studies have examined the mechanisms how chickens react to infection. Apart from the innate immune response, many physiological mechanisms and pathways are reported to be involved in the chicken host response to Salmonella infection. The objective of this study was to perform a meta-analysis of diverse experiments to identify general and host specific mechanisms to the Salmonella challenge. Results Diverse chicken lines differing in susceptibility to Salmonella infection were challenged with different Salmonella serovars at several time points. Various tissues were sampled at different time points post-infection, and resulting host transcriptional differences investigated using different microarray platforms. The meta-analysis was performed with the R-package metaMA to create lists of differentially regulated genes. These gene lists showed many similarities for different chicken breeds and tissues, and also for different Salmonella serovars measured at different times post infection. Functional biological analysis of these differentially expressed gene lists revealed several common mechanisms for the chicken host response to Salmonella infection. The meta-analysis-specific genes (i.e. genes found differentially expressed only in the meta-analysis confirmed and expanded the biological functional mechanisms. Conclusions The meta-analysis combination of heterogeneous expression profiling data provided useful insights into the common metabolic pathways and functions of different chicken lines infected with different Salmonella serovars.

  9. 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. PMID:27074614

  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 Malaysia. PMID:27118863

  11. Estimation of Water Vapour Attenuation And Rain Attenuation

    Directory of Open Access Journals (Sweden)

    K.Kalyana Srinivas

    2015-04-01

    Full Text Available Attenuation due to and water vapour and rain can severely degrade the radio wave propagation at centimeter or millimeter wavelengths. It restricts the path length of radio communication systems and limits the use of higher frequencies for line-of-sight microwave links and satellite communications. The attenuation will pose a greater problem to communication as the frequency of occurrence of heavy rain increases.In a tropical region, like Malaysia, where excessive rainfall is a common phenomenon throughout the year, the knowledge of the rain attenuation at the frequency of operation is extremely required for the design of a reliable terrestrial and earth space communication link at a particular location.

  12. Genetic Relatedness of Salmonella Isolates from Nondomestic Birds in Southeastern United States

    OpenAIRE

    Hudson, Charlene R.; Quist, Charlotte; Lee, Margie D.; Keyes, Kathleen; Dodson, Sara V.; Morales, Cesar; Sanchez, Susan; White, David G.; Maurer, John J.

    2000-01-01

    Salmonella infections have been implicated in large-scale die-offs of wild birds in the United States. Although we know quite a bit about the epidemiology of Salmonella infection among domestic fowl, we know little about the incidence, epidemiology, and genetic relatedness of salmonellae in nondomestic birds. To gain further insight into salmonellae in these hosts, 22 Salmonella isolates from diseased nondomestic birds were screened for the presence of virulence and antibiotic resistance-asso...

  13. Immediate differentiation of salmonella-resembling colonies on brilliant green agar

    DEFF Research Database (Denmark)

    Jensen, Annette Nygaard; Hoorfar, Jeffrey

    2000-01-01

    A rapid biochemical system (OBIS) based on immediate enzymatic differentiation of Citrobacter, Proteus, Providencia, Hafnia and Morganella spp. from Salmonella on brilliant green agar was evaluated A total of 96 field isolates from various Salmonella serotypes, 18 Citrobacter freundii and 25...... isolates of other Enterobacteriaceae were tested All Salmonella isolates were identified correctly by the kit, and none of the Enterobacteriaceae isolates were identified as Salmonella. The results indicate complete specificity for Salmonella colonies on brilliant green agar....

  14. The attenuation and the attenuators: strategies and tactics

    Directory of Open Access Journals (Sweden)

    Antonio Briz

    2013-12-01

    Full Text Available This work is inscribed in a research project (ES.POR.ATENUAÇÃO that seeks to analyze and explain the attenuator activity in different regional varieties of Spanish and Portuguese, in order to perform, subsequently, different contrastive intralinguistic and interlinguistic studies. In this article, we explain some of the theoretical and methodological principles on which are based the qualitative and quantitative analysis. And especially, we will refer to the concept of attenuation (Briz 1995, 2002, 2003, 2005, 2007a, 2012.

  15. Molecular fingerprinting of Salmonella enterica subsp. enterica Typhimurium and Salmonella enterica subsp. enterica derby isolated from tropical seafood in South India.

    Science.gov (United States)

    Kumar, Rakesh; Surendran, P K; Thampuran, Nirmala

    2008-09-01

    Salmonella enterica subsp. enterica Typhimurium and Salmonella enterica subsp. enterica Derby strains isolated from different seafood were genotyped by PCR-ribotyping and ERIC-PCR assays. This study has ascertained the genetic relatedness among serovars prevalent in tropical seafood. PCR-ribotyping exhibited genetic variation in both Salmonella serovars, and ribotype profile (II) was most predominant, which was observed in 10/18 of Salmonella enterica subsp. enterica Typhimurium and 7/17 Salmonella enterica subsp. enterica Derby isolates. Cluster analysis of ERIC-PCR for Salmonella enterica subsp. enterica Typhimurium strains exhibited nine different banding patterns and four strains showed >95% genetic homology within the cluster pairs. ERIC-PCR produced more genetic variations in Salmonella enterica subsp. enterica Typhimurium; nevertheless, both methods were found to be comparable for Salmonella enterica subsp. enterica Derby isolates. Discrimination index of PCR-ribotyping for Salmonella enterica subsp. enterica Typhimurium isolates was obtained at 0.674 and index value 0.714 was observed for Salmonella enterica subsp. enterica Derby strains. Molecular fingerprinting investigation highlighted the hypothesis of diverse routes of Salmonella contamination in seafood as multiple clones of Salmonella enterica subsp. enterica Typhimurium and Salmonella enterica subsp. enterica Derby were detected in same or different seafood throughout the study period. PMID:18480975

  16. Simultaneous Detection of <i>Salmonella</i> spp., <i>Salmonella</i> Enteritidis and <i>Salmonella</i> Typhimurium in Raw Salad Vegetables and Vegetarian Burger Patties

    OpenAIRE

    Elexson Nillian; Chai Lay Ching; Pui Chai Fung; Tunung Robin; Ubong Anyi; Tuan Zainazor Tuan Chilek; Son Radu; Mitsuaki Nishibuchi

    2011-01-01

    The health risks posed by Salmonella spp., Salmonella Enteritidis and Salmonella Typhimurium through the consumption of raw vegetables and vegetarian burger patties necessitates the needs for the optimization of analytical approach for their detection and enumeration in the raw vegetables, which served as potential vehicles for transmission of these pathogenic microorganisms. We sought to establish a rapid, economic and sensitive method to detect and determine the load of Salmonella spp., Sal...

  17. Phosphate starvation regulon of Salmonella typhimurium.

    OpenAIRE

    Foster, J. W.; Spector, M P

    1986-01-01

    Several phosphate-starvation-inducible (psi) genetic loci in Salmonella typhimurium were identified by fusing the lacZ gene to psi promoters by using the Mu d1 and Mu d1-8 bacteriophages. Although several different starvation conditions were examined, the psi loci responded solely to phosphate deprivation. A regulatory locus, psiR, was identified as controlling the psiC locus. The psiR locus did not affect the expression of the Escherichia coli phoA locus or any of the other psi loci described.

  18. Sound attenuation in magnetorheological fluids

    Science.gov (United States)

    Rodríguez-López, J.; Elvira, L.; Resa, P.; Montero de Espinosa, F.

    2013-02-01

    In this work, the attenuation of ultrasonic elastic waves propagating through magnetorheological (MR) fluids is analysed as a function of the particle volume fraction and the magnetic field intensity. Non-commercial MR fluids made with iron ferromagnetic particles and two different solvents (an olive oil based solution and an Araldite-epoxy) were used. Particle volume fractions of up to 0.25 were analysed. It is shown that the attenuation of sound depends strongly on the solvent used and the volume fraction. The influence of a magnetic field up to 212 mT was studied and it was found that the sound attenuation increases with the magnetic intensity until saturation is reached. A hysteretic effect is evident once the magnetic field is removed.

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

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    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.

  20. THE DYNAMICS OF ANTIMICROBIAL RESISTANCE OF Salmonella typhimurium ISOLATES.

    Directory of Open Access Journals (Sweden)

    Erleta Peqini

    2011-04-01

    Full Text Available Salmonella typhimurium is the most common pathogen isolated in foodstuffs toxin infections. The development of antibiotic resistance in Salmonella typhimurium over the last twenty years is caused by an extensive application of some antibiotics. The study of antimicrobial resistance of Salmonella typhimurium isolates helps the physicians in using the indispensable antibiotic and replacing the resistant antibiotics with new ones. The aim of this study was to determine the prevalence of antimicrobial resistance of Salmonella typhimurium isolates of persons with foodstuff’s toxin infections in Elbasan region during the years 1985-2004, to which are made the antibiograms and the antimicrobial resistance. This study includes 2931 Salmonella typhimurium strains in this period of time. All the strains were tested using disk diffusion method (with antibiotics: AM, S, TE, C, K, GM, SXT, NA and CIP. Salmonella typhimurium strains have been more resistant to Ampicilin (98.29 %, Tetracycline (93.48 %, Streptomycin (78.92 %, Bactrim (64.14 %.The reason of passivity of such antibiotics against Salmonella typhimurium is their use, in most cases, without doing the antibiograms in each case and physicians have used very often the above antibiotics, bringing about the intensification of bacteria’s resistance towards them.

  1. Salmonella bacteraemia among healthcare workers and their dependents

    International Nuclear Information System (INIS)

    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)

  2. Elimination of salmonella from fermented pork by gamma irradiation

    International Nuclear Information System (INIS)

    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 106, 104, or 102 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 106 per g; 0.3 Mrad eliminated 106/g of S. newport and S. paratyphi B and 104/g of S. derby and S. anatum; and 0.2 Mrad eliminated 102/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

  3. Salmonella contamination during production of cantaloupe: a binational study.

    Science.gov (United States)

    Castillo, A; Mercado, I; Lucia, L M; Martínez-Ruiz, Y; Ponce de León, J; Murano, E A; Acuff, G R

    2004-04-01

    Six cantaloupe farms and packing plants in South Texas (950 cantaloupe, 140 water, and 45 environmental samples), including the Rio Grande Valley area, and three farms in Colima State, Mexico (300 cantaloupe, 45 water, and 15 environmental samples), were sampled to evaluate cantaloupe contamination with Salmonella and Escherichia coli during production and processing. Samples collected from external surfaces of cantaloupes, water, and the environments of packing sheds on cantaloupe farms were examined for the presence of Salmonella and E. coli. Of a total of 1,735 samples collected, 31 (1.8%) tested positive for Salmonella. Fifteen Salmonella serotypes were isolated from samples collected in Texas, and nine from samples collected in Colima. Two serotypes (Poona and Oranienburg) that have been associated with three large Salmonella outbreaks in the United States and Canada linked to the consumption of contaminated cantaloupe were found in water samples collected at four farms (three from the United States). Susceptibility of Salmonella isolates to 10 antimicrobials was evaluated by disk diffusion. Eighty-eight percent of the isolates from the United States and Mexico were pansusceptible to the antimicrobials tested; eight isolates from the United States demonstrated an intermediate susceptibility to streptomycin and only two isolates were resistant to the same antimicrobial. From Mexico, four isolates showed an intermediate susceptibility to streptomycin and one isolate was resistant to nalidixic acid and streptomycin. Repetitive sequence-based PCR analysis of Salmonella isolates helped to trace potential sources of Salmonella contamination in source water and in subsequent water samples obtained after the filtration systems of U.S. and Mexican cantaloupe farms. No differences could be seen between the levels of Salmonella contamination in melons from both countries. PMID:15083723

  4. Chimeric flagellin expressed by Salmonella typhimurium induces an ESAT-6-specific Th 1-type immune response and CTL effects following intranasal immunization

    Institute of Scientific and Technical Information of China (English)

    Hui Zhang; Liu Liu; Ke Wen; Jinlin Huang; Shizhong Geng; Junsong Shen; Zhiming Pan; Xinan Jiao

    2011-01-01

    The flagellin component FliC of Salmonella typhimurium is capable of activating the innate immune system via specific interactions with TLR5 and can also act as a carrier of foreign antigen to elicit antigen-specific immune responses.Thus,we constructed an attenuated Salmonella strain SL5928(fliC/esat) expressing chimeric flagellin that contained the ESAT-6 antigen coding sequence of Mycobacterium tuberculosis inserted into the highly variable region of the Salmonella flagellin coding gene fliCi.The chimeric flagellin functioned normally,as demonstrated using a flagella swarming assay and electron microscopy.To analyze the effects of chimeric flagellin,the cell-mediated immune response and cytotoxic T lymphocyte (CTL) effects specific for ESAT-6antigen were tested after intranasal immunization of mice with flagellated Salmonella SL5928(fliC/esat).The results showed that SL5928(fliC/esat) intranasal immunization can strongly elicit an ESAT-6-specific T helper (Th) 1-type immune response in mucosal lymphoid tissues,such as nasopharynx-associated lymph nodes,lung and Peyer's patches,and a Th 1/Th2 response was elicited in spleen and mesenteric lymph nodes.Furthermore,intranasal immunization of SL5928(fliC/esat) produced efficient CTL effects,as demonstrated using a 5-and 6-carboxyfluorescein diacetate succinimidyl ester (CFSE) assay.Thus,our study revealed that Salmonella flagellin acts as a carrier for foreign antigen and triggers strong Th 1 and CTL responses during intranasal immunization.Chimeric flagellin is potentially an effective strategy for the development of novel vaccines against tuberculosis in humans and animals.

  5. Identification of conserved amino acid residues of the Salmonella sigmaS chaperone Crl involved in Crl-sigmaS interactions.

    Science.gov (United States)

    Monteil, Véronique; Kolb, Annie; D'Alayer, Jacques; Beguin, Pierre; Norel, Françoise

    2010-02-01

    Proteins that bind sigma factors typically attenuate the function of the sigma factor by restricting its access to the RNA polymerase (RNAP) core enzyme. An exception to this general rule is the Crl protein that binds the stationary-phase sigma factor sigma(S) (RpoS) and enhances its affinity for the RNAP core enzyme, thereby increasing expression of sigma(S)-dependent genes. Analyses of sequenced bacterial genomes revealed that crl is less widespread and less conserved at the sequence level than rpoS. Seventeen residues are conserved in all members of the Crl family. Site-directed mutagenesis of the crl gene from Salmonella enterica serovar Typhimurium and complementation of a Deltacrl mutant of Salmonella indicated that substitution of the conserved residues Y22, F53, W56, and W82 decreased Crl activity. This conclusion was further confirmed by promoter binding and abortive transcription assays. We also used a bacterial two-hybrid system (BACTH) to show that the four substitutions in Crl abolish Crl-sigma(S) interaction and that residues 1 to 71 in sigma(S) are dispensable for Crl binding. In Escherichia coli, it has been reported that Crl also interacts with the ferric uptake regulator Fur and that Fur represses crl transcription. However, the Salmonella Crl and Fur proteins did not interact in the BACTH system. In addition, a fur mutation did not have any significant effect on the expression level of Crl in Salmonella. These results suggest that the relationship between Crl and Fur is different in Salmonella and E. coli. PMID:20008066

  6. Salmonella enterica serovar Typhi Ty21a expressing human papillomavirus type 16 L1 as a potential live vaccine against cervical cancer and typhoid fever.

    Science.gov (United States)

    Fraillery, Dominique; Baud, David; Pang, Susana Yuk-Ying; Schiller, John; Bobst, Martine; Zosso, Nathalie; Ponci, Françoise; Nardelli-Haefliger, Denise

    2007-10-01

    Human papillomavirus (HPV) vaccines based on L1 virus-like particles (VLPs) can prevent HPV-induced genital neoplasias, the precursors of cervical cancer. However, most cervical cancers occur in developing countries, where the implementation of expensive vaccines requiring multiple injections will be difficult. A live Salmonella-based vaccine could be a lower-cost alternative. We previously demonstrated that high HPV type 16 (HPV16)-neutralizing titers are induced after a single oral immunization of mice with attenuated Salmonella enterica serovar Typhimurium strains expressing a codon-optimized version of HPV16 L1 (L1S). To allow the testing of this type of vaccine in women, we constructed a new L1-expressing plasmid, kanL1S, and tested kanL1S recombinants of three Salmonella enterica serovar Typhi vaccine strains shown to be safe in humans, i.e., Ty21a, the actual licensed typhoid vaccine, and two highly immunogenic typhoid vaccine candidates, Ty800 and CVD908-htrA. In an intranasal mouse model of Salmonella serovar Typhi infection, Ty21a kanL1S was unique in inducing HPV16-neutralizing antibodies in serum and genital secretions, while anti-Salmonella responses were similar to those against the parental Ty21a vaccine. Electron microscopy examination of Ty21a kanL1S lysates showed that L1 assembled in capsomers and capsomer aggregates but not well-ordered VLPs. Comparison to the neutralizing antibody response induced by purified HPV16 L1 VLP immunizations in mice suggests that Ty21a kanL1S may be an effective prophylactic HPV vaccine. Ty21a has been widely used against typhoid fever in humans with a remarkable safety record. These finds encourage clinical testing of Ty21a kanL1S as a combined typhoid fever/cervical cancer vaccine with the potential for worldwide application. PMID:17687110

  7. Salmonella y aflatoxinas en granjas de gallinas ponedoras comerciales

    OpenAIRE

    Soria, María Cecilia

    2013-01-01

    El objetivo del presente trabajo fue determinar la prevalencia de bacterias del género Salmonella en granjas de gallinas ponedoras comerciales de la provincia de Entre Ríos, como así también la presencia de aflatoxinas en los huevos producidos en estos establecimientos. Además, se evaluaron los factores de riesgo asociados a la presencia de Salmonella y/o aflatoxinas. Se evaluaron metodologías de aislamiento bacteriológico y técnicas de PCR para la detección de Salmonella sp. en alimento, exc...

  8. Recovery of Salmonella group B from blood and Salmonella group C2 from feces and serological evidence of dual infection in one patient.

    OpenAIRE

    Papasian, C J; Bartholomew, W R; Neter, E.; Amsterdam, D

    1984-01-01

    A patient with a dual Salmonella infection is described. Salmonella group B was recovered from three blood culture sets but was not detected in seven stool cultures. Salmonella group C2 was isolated from three of seven stool cultures but was not recovered from blood cultures. Specific, non-cross-reactive antibodies to Salmonella groups B and C2 were detected in the sera of the patient by passive hemagglutination assays.

  9. Invasion Genes Are Not Required for Salmonella enterica Serovar Typhimurium To Breach the Intestinal Epithelium: Evidence That Salmonella Pathogenicity Island 1 Has Alternative Functions during Infection

    OpenAIRE

    Murray, Rose Ann; Lee, Catherine A.

    2000-01-01

    Salmonella enterica serovar Typhimurium invasion genes are necessary for bacterial invasion of intestinal epithelial cells and are thought to allow salmonellae to enter and cross the intestinal epithelium during infection. Many invasion genes are encoded on Salmonella pathogenicity island 1 (SPI1), and their expression is activated by HilA, a transcription factor also encoded on SPI1. We have studied the role of Salmonella invasion genes during infection of mice following intragastric inocula...

  10. Complete Genome and Methylome Sequences of Salmonella enterica subsp. enterica Serovar Panama (ATCC 7378) and Salmonella enterica subsp. enterica Serovar Sloterdijk (ATCC 15791)

    OpenAIRE

    Yao, Kuan; Muruvanda, Tim; Roberts, Richard J.; Payne, Justin; Allard, Marc W.; Hoffmann, Maria

    2016-01-01

    Salmonella enterica spp. are pathogenic bacteria commonly associated with food-borne outbreaks in human and animals. Salmonella enterica spp. are characterized into more than 2,500 different serotypes, which makes epidemiological surveillance and outbreak control more difficult. In this report, we announce the first complete genome and methylome sequences from two Salmonella type strains associated with food-borne outbreaks, Salmonella enterica subsp. enterica serovar Panama (ATCC 7378) and S...

  11. Evaluation of two colored latex kits, the Wellcolex Colour Salmonella Test and the Wellcolex Colour Shigella Test, for serological grouping of Salmonella and Shigella species.

    OpenAIRE

    Bouvet, P J; Jeanjean, S.

    1992-01-01

    Two colored latex kits (the Wellcolex Colour Salmonella Test [WCT-Salmonella] and the Wellcolex Colour Shigella Test [WCT-Shigella]; Division Diagnostics, Laboratories Wellcome S.A., Paris, France), which allow identification of the most frequently encountered Salmonella serogroups and Shigella species, respectively, were evaluated. WCT-Salmonella and WCT-Shigella yielded sensitivities of 98.4 and 98%, respectively, and a specificity of 100% when they were tested on pure cultures received at ...

  12. Detection of Salmonella and several common Salmonella serotypes in food by loop-mediated isothermal amplification method

    Directory of Open Access Journals (Sweden)

    Zhongqiang Chen

    2015-06-01

    Full Text Available Salmonella Choleraesuis, S. Enteritidis and S. Typhimurium are the main pathogens that contaminate animal products and cause human Salmonella food poisoning. To establish the loop-mediated isothermal amplification (LAMP method for the rapid detection of Salmonella and 3 common Salmonella serotypes, inner and outer primer sets targeting Salmonella invE gene and 3 serotype-specific genes fliC, lygD and STM4495 were designed. The LAMP reaction conditions were optimized. The specificity of LAMP primers was identified by testing 10 different bacterial strains including S. Choleraesuis, S. Enteritidis and S. Typhimurium. Take S. Choleraesuis as example, the detection limit of LAMP assay was 1.33 × 101 CFU/mL for bacteria culture and 2.0 × 101 CFU/mL for simulated pork sample. The results show that LAMP is a rapid, sensitive and specific method for Salmonella detection and can be used for the rapid detection of Salmonella in food.

  13. 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.......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...... delivered from the same hatchery. Because these two salmonella types had not been detected in the Danish broiler sector before and the broiler houses were infected in a period of low salmonella prevalence, the study could focus on farm-related factors, without being distorted by other salmonella infections...

  14. Josephson tunnel junction microwave attenuator

    DEFF Research Database (Denmark)

    Koshelets, V. P.; Shitov, S. V.; Shchukin, A. V.;

    1993-01-01

    A new element for superconducting electronic circuitry-a variable attenuator-has been proposed, designed, and successfully tested. The principle of operation is based on the change in the microwave impedance of a superconductor-insulator-superconductor (SIS) Josephson tunnel junction when dc biased...

  15. Compact plasmonic variable optical attenuator

    DEFF Research Database (Denmark)

    Leosson, Kristjan; Rosenzveig, Tiberiu; Hermannsson, Pétur Gordon;

    2008-01-01

    We demonstrate plasmonic nanowire-based thermo-optic variable optical attenuators operating in the 1525-1625 nm wavelength range. The devices have a footprint as low as 1 mm, extinction ratio exceeding 40 dB, driving voltage below 3 V, and full modulation bandwidth of 1 kHz. The polarization...

  16. Attenuation of Vrancea events revisited

    International Nuclear Information System (INIS)

    New aspects of the frequency-dependent attenuation of the seismic waves traveling from Vrancea subcrustal sources toward NW (Transylvanian Basin) and SE (Romanian Plain) are evidenced by the recent experimental data made available by the CALIXTO'99 tomography experiment. The observations validate the previous theoretical computations performed for the assessment, by means of a deterministic approach, of the seismic hazard in Romania. They reveal an essential aspect of the seismic ground motion attenuation, that has important implications on the probabilistic assessment of seismic hazard from Vrancea intermediate-depth earthquakes. The attenuation toward NW is shown to be a much stronger frequency-dependent effect than the attenuation toward SE and the seismic hazard computed by the deterministic approach fits satisfactorily well the observed ground motion distribution in the low-frequency band (< 1 Hz). The apparent contradiction with the historically-based intensity maps arises mainly from a systematic difference in the vulnerability (buildings eigenperiod) of the buildings in the intra- and extra-Carpathians regions. (author)

  17. Genes Required for the Fitness of Salmonella enterica Serovar Typhimurium during Infection of Immunodeficient gp91−/− phox Mice

    Science.gov (United States)

    Oshota, Olusegun; Chaudhuri, Roy R.; Mayho, Matthew; Peters, Sarah E.; Clare, Simon; Maskell, Duncan J.; Mastroeni, Pietro

    2016-01-01

    Salmonella enterica causes systemic diseases (typhoid and paratyphoid fever), nontyphoidal septicemia (NTS), and gastroenteritis in humans and other animals worldwide. An important but underrecognized emerging infectious disease problem in sub-Saharan Africa is NTS in children and immunocompromised adults. A current goal is to identify Salmonella mutants that are not pathogenic in the absence of key components of the immune system such as might be found in immunocompromised hosts. Such attenuated strains have the potential to be used as live vaccines. We have used transposon-directed insertion site sequencing (TraDIS) to screen mutants of Salmonella enterica serovar Typhimurium for their ability to infect and grow in the tissues of wild-type and immunodeficient mice. This was to identify bacterial genes that might be deleted for the development of live attenuated vaccines that would be safer to use in situations and/or geographical areas where immunodeficiencies are prevalent. The relative fitness of each of 9,356 transposon mutants, representing mutations in 3,139 different genes, was determined in gp91−/− phox mice. Mutations in certain genes led to reduced fitness in both wild-type and mutant mice. To validate these results, these genes were mutated by allelic replacement, and resultant mutants were retested for fitness in the mice. A defined deletion mutant of cysE was attenuated in C57BL/6 wild-type mice and immunodeficient gp91−/− phox mice and was effective as a live vaccine in wild-type mice. PMID:26787719

  18. Stormwater Attenuation by Green Roofs

    Science.gov (United States)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  19. Glyceraldehyde phosphate at the reducing terminus of Salmonella Q haptens. Salmonella montevideo.

    Science.gov (United States)

    Gmeiner, J

    1975-02-21

    The O antigen polysaccharide of Salmonella montevideo was isolated from a core-defective mutant by the phenol/water procedure, and was suspected to contain phosphomonester and cyclic phosphodiester at its reducing end in anology to the O hapten from Salmonella typhimurium (Kent and Obsborn, 1968. Therefore, it was chromatographed on a DEAE-cellulose column. Whereas one part eluted with water the other part of the polysaccharide could only be eluted with buffer. Both fractions were further purified on Sephadex G100 and contained mannose, glucose, N-acetylglucosamine and phosphate in a molar ratio of 4:1:1: less than 0.1. In order to specifically label the reducing end phosphate was removed enzymatically, or the presumed cyclic diester was cleaved by mild hydrolysis, and the fractions were reduced with sodium horo[3H]hydride. Both fractions yield mainly [3H]glycerol after hydrolysis and paper chromatogaphy. In addition, [3H]mannitol and [H]monohydroxyacetone could be identified by paper chromatography and were concluded to be the result of phosphate migration and beta-elimination reactions taking place during the isolation procedure and the various treatments prior to sodium boro[3H]hydride reduction. These findings in addition to periodate oxidation studies indicated that the O antigen polysaccharide of Salmonella montevideo had glyceraldehyde phosphate at its reducing end. From the incorporation of 3H into the polysaccharide the O antigen was calculated to consist of about 19 repeating units of 6 sugar residues each. PMID:1097244

  20. Biological effect of plutonium 239 on Salmonella typhimurium

    International Nuclear Information System (INIS)

    Salmonella typhimurium cells were exposed in a 239Pu citrate solution. Cell death and induction of gene mutations were an exponential fucntion of γ-radiation dose. LD37 was 34.8 Gy; mutation doubling dose, 19 Gy

  1. Radiation processing for the control of Salmonella in frog legs

    International Nuclear Information System (INIS)

    Large consignments of frogs legs are exported annually from India. Failure to satisfy some of the strict microbiological standards, especially in relating to Salmonellae contamination, has resulted in the rejection of large quantities of the product in recent years. This has emphasised the need for better and more effective methods than those currently in use for the elimination of Salmonellae. With a view to developing an irradiation process for the control of this public health problem, commercial samples of frog legs have been screened to assess the incidence of Salmonella. The various serotypes have been identified and their radiation sensitivities determined. Based on these data, a radiation treatment of frozen frog legs for the elimination of Salmonella has been developed. (author)

  2. Population structure of Salmonella investigated by amplified fragment length polymorphism

    DEFF Research Database (Denmark)

    Torpdahl, M.; Ahrens, Peter

    2004-01-01

    whereas others are highly divergent. Conclusions: AFLP clearly clustered strains representing the subgroups of Salmonella together with high bootstrap values and the serotypes of subspecies enterica were divided into polyphyletic or monophyletic types corresponding well with multilocus enzyme...

  3. Salmonella: Dry Pet Foods and Pet Treats (FAQ)

    Science.gov (United States)

    ... Guides Reports Salmonella: Dry Pet Foods and Pet Treats (FAQ) Originally posted August 9, 2010; Updated August ... as a result of the outbreak. “Natural” pet treats , such as pig ears and dehydrated/dried beef ...

  4. Automated 5 ' nuclease PCR assay for identification of Salmonella enterica

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Ahrens, Peter; Rådström, P.

    2000-01-01

    isolates, including 100 problematic "rough" isolates. An internal positive control was designed to use the same Salmonella primers for amplification of a spiked nonrelevant template (116 bp) in the sample tube. The PCR test correctly identified all the Salmonella strains by resulting in positive end......A simple and ready-to-go test based on a 5' nuclease (TaqMan) PCR technique was developed for identification of presumptive Salmonella enterica isolates. The results were compared with those of conventional methods. The TaqMan assay was evaluated for its ability to accurately detect 210 S. enterica...... Salmonella strains tested resulted in positive FAM and TET signals. In addition, it was found that the complete PCR mixture, predispensed in microwell plates, could be stored for up to 3 months at -20 degrees C, Thus, the diagnostic TaqMan assay developed can be a useful and simple alternative method for...

  5. Ionizing Radiation for the Elimination of Salmonellae from Frozen Meat

    International Nuclear Information System (INIS)

    The radiation resistance in frozen meat of a number of different serotypes of Salmonella has been examined. A dose of 0.65 Mrad achieves a 106 reduction in the numbers of the most resistant types and this dose has been shown to be effective in eliminating salmonellae from naturally contaminated meat. Some results are outlined which show that (a) Salmonella resistance is higher in frozen meat than in unfrozen meat, (b) pre-irradiation growth of the organisms in meat does not influence resistance, (c) salmonellae surviving irradiation grow at a slower rate than unirradiated organisms and appear to be unchanged in serological properties or phage type. Reference is made to wholesomeness tests carried out on irradiated meat and to the current situation on legislation in the United Kingdom controlling the irradiation of food. The identification of irradiated food is also mentioned. (author)

  6. Physical maps of Klebsiella aerogenes and Salmonella typhimurium hut genes.

    OpenAIRE

    Blumenberg, M; Magasanik, B

    1981-01-01

    The recognition sites for several restriction endonucleases were mapped within deoxyribonucleic acid coding for histidine utilization (hut) genes of Salmonella typhimurium and Klebsiella aerogenes. Deoxyribonucleic acid fragments containing the two hut promoters were identified by ribonucleic acid polymerase binding.

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

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Torpdahl, Mia; Zachariasen, Camilla;

    2012-01-01

    The objective of this research was to determine minimal inhibitory concentration (MIC) population distributions for colistin for Salmonella on subtype level. Furthermore, we wanted to determine if differences in MIC for colistin could be explained by mutations in pmrA or pmrB encoding proteins...... involved in processes that influence the binding of colistin to the cell membrane. During 2008–2011, 6,583 Salmonella enterica subsp. enterica isolates of human origin and 1931 isolates of animal/meat origin were collected. The isolates were serotyped, and susceptibility was tested towards colistin (range...... 1–16 mg/L). Moreover, 37 isolates were tested for mutations in pmrA and pmrB by polymerase chain reaction (PCR) and DNA sequencing. MIC distribution for colistin at serotype level showed that Salmonella Dublin (n=198) followed by Salmonella Enteritidis (n=1247) were less susceptible than “other...

  8. Outbreak of Salmonella food poisoning at Junior World Rowing Championships.

    OpenAIRE

    Anderson, A C

    1996-01-01

    This paper describes an outbreak of Salmonella enteriditis occurring at the Junior World Rowing Championships at Poznan, Poland, in August 1995 which was to have a significant effect on the performance of several of the largest national teams.

  9. Salmonella enterica Serovar Typhi Variants in Long-Term Carriers

    OpenAIRE

    Chiou, Chien-Shun; Wei, Hsiao-Lun; Mu, Jung-Jung; Liao, Ying-Shu; Liang, Shiu-Yun; Liao, Chun-Hsing; Tsao, Chi-Sen; Wang, Shu-Chuan

    2013-01-01

    Long-term typhoid carriers can simultaneously excrete Salmonella enterica serovar Typhi variants with considerable genetic differences, a situation that complicates the interpretation of the subtyping data used in outbreak investigations and disease surveillance.

  10. Salmonella arizonae in the United Kingdom from 1966 to 1990.

    OpenAIRE

    Hall, M. L.; Rowe, B.

    1992-01-01

    Salmonella arizonae are rarely isolated in the UK. Since 1966 there have been sixty-six isolates from humans of whom 35% gave a recent history of foreign travel. Terrapins and snakes are potential sources of infection.

  11. Salmonella on pig carcassess during slaughter and processing

    Directory of Open Access Journals (Sweden)

    Karabasil Nedeljko

    2012-01-01

    Full Text Available Salmonella is one of the most important zoonotic pathogens and the consumption of pork meat is one of the major sources of human infection. The aim of this study was to investigate the presence of salmonella on pig carcasses. Samples were taken from slaughterhouse A in two instances (sampling I and II, a total of 300 samples and in slaughterhouse B once (sampling III, a total of 120 samples, from pork carcasses after the stunning and after the processing. Of the total number of examined samples, the percentage of positive samples for salmonella from pork carcasses after stunning was 46.7% (90/42, and samples from the carcasses after processing 3.3% (90/3. Operations taking place on the slaughter line could have an effect on the salmonella contamination of carcasses.

  12. İmmunomanyetik Ayırma Yöntem ile Gıdalardan Salmonella spp. İzolasyonu

    OpenAIRE

    Mercanoğlu, Birce; Aytaç, S. Aykut

    2005-01-01

    In this study, firstly the specificity of Dynabeads® antiâ€'Salmonella has been examined and then (immunomagnetic separation) IMS method has been investigated in order to isolate Salmonella spp. from 50 food samples assumed that having the contamination of Salmonella risk in parallel with the traditional cultural method that is ISO 6579 reference method. Also Salmonella enteritidis, antiâ€'Salmonella beads and the S. enteritidis +Dynabeads® antiâ€'Salmonella complex...

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

    International Nuclear Information System (INIS)

    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/cm2/sr, Salmonella treatment: 6.35E+05 p/s/cm2/sr, E. coli treatment: 1.29E+07 p/s/cm2/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

  14. Oral Immunization with a Salmonella typhimurium Vaccine Vector Expressing Recombinant Enterotoxigenic Escherichia coli K99 Fimbriae Elicits Elevated Antibody Titers for Protective Immunity

    OpenAIRE

    Ascón, Miguel A.; Hone, David M.; Walters, Nancy; Pascual, David W.

    1998-01-01

    Bovine enterotoxigenic Escherichia coli (ETEC) continues to cause mortality in piglets and newborn calves. In an effort to develop a safe and effective vaccine for the prevention of F5+ ETEC infections, a balanced lethal asd+ plasmid carrying the complete K99 operon was constructed and designated pMAK99-asd+. Introduction of this plasmid into an attenuated Salmonella typhimurium Δaro Δasd strain, H683, resulted in strain AP112, which stably expresses E. coli K99 fimbriae. A single oral immuni...

  15. Rapid detection of Salmonella in foods using a combination of SPRINT TM,MSRV TM and Salmonella Latex TestTM Detecção rápida de Salmonella em alimentos empregando uma combinação de SPRINT®, MSRV® e Salmonella Latex Test®

    OpenAIRE

    Jane Maria Lafayette Neves Gelinski; Gunnar Martin; Maria Teresa Destro; Mariza Landgraf; Bernadette Dora Gombossy de Melo Franco

    2002-01-01

    A new procedure for rapid detection of Salmonella in foods, based on the combination of SPRINT TM, MSRV TM and Salmonella Latex TestTM, was evaluated. SPRINT TM is a system to reduce the preenrichment and selective enrichment steps to 24 hours. MSRV TM is a semi-solid selective media for detection of motile Salmonella. Salmonella Latex TestTM is a rapid latex agglutination test for Salmonella. Using the three systems in combination, the total time for detection of Salmonella in a food sample ...

  16. Molecular Detection of Salmonella Serovar Isolated from Eggs

    OpenAIRE

    Monadi, M. (MSc; M Kargar; Naghiha, A. (PhD; Najafi, A. (MSc; Mohammadi, R. (MSc

    2015-01-01

    Background and Objective: Salmonellosis is the most common type of food poisoning in developed and developing countries that is caused by Salmonella serotype. Hence, we aimed to identify the Salmonella serovars in eggs obtained from Kohgiluyeh and Boyerahmad province and to evaluate antibiotic resistance of the isolated strains. Material and Methods: In this study, 210 eggs were collected from Kohgiluyeh and Boyerahmad Province. The bacteria were isolated and identified using biochemical test...

  17. Salmonella Alachua: causative agent of a foodborne disease outbreak

    OpenAIRE

    Ivete Aparecida Zago Castanheira de Almeida; Jacqueline Tanury Macruz Peresi; Elisabete Cardiga Alves; Denise Fusco Marques; Inara Siqueira de Carvalho Teixeira; Sonia Izaura de Lima e Silva; Sandra Regina Ferrari Pigon; Monique Ribeiro Tiba; Sueli Aparecida Fernandes

    2015-01-01

    Objectives: The aim of this study is to report the occurrence of the first outbreak of food poisoning caused by SalmonellaAlachua in Brazil, as well as the antimicrobial susceptibility and the genetic relatedness of SalmonellaAlachua strains isolated from clinical and food samples.Material and methods: To elucidate the outbreak, an epidemiological investigation was carried out, and two samples of common food were tested - mayonnaise salad and galinhada(a traditional Brazilian dish of chicken ...

  18. Acquisition of the lac operon by Salmonella enterica

    OpenAIRE

    Leonard, Susan R.; Lacher, David W.; Lampel, Keith A.

    2015-01-01

    Background Classical bacteriological characteristics of Salmonella enterica indicate that the members of this species are unable to utilize lactose as a carbon source. However, lactose-fermenting (Lac+) strains of several Salmonella serovars have been isolated from different foodborne outbreaks as well as different geographical regions worldwide. In the present study, we sequenced the genomes of 13 Lac + S. enterica isolates and characterized the lac region, comparing it to the lac region in ...

  19. Fitness of Salmonella enterica serovar Thompson in the Cilantro Phyllosphere

    OpenAIRE

    Maria T Brandl; Mandrell, Robert E.

    2002-01-01

    The epiphytic fitness of Salmonella enterica was assessed on cilantro plants by using a strain of S. enterica serovar Thompson that was linked to an outbreak resulting from cilantro. Salmonella serovar Thompson had the ability to colonize the surface of cilantro leaves, where it was detected by confocal laser scanning microscopy (CLSM) at high densities on the veins and in natural lesions. The population sizes of two common colonizers of plant surfaces, Pantoea agglomerans and Pseudomonas chl...

  20. Formate Acts as a Diffusible Signal To Induce Salmonella Invasion▿

    OpenAIRE

    Huang, Yanyan; Suyemoto, Mitsu; Garner, Cherilyn D.; Cicconi, Kellie M.; Altier, Craig

    2008-01-01

    To infect an animal host, Salmonella enterica serovar Typhimurium must penetrate the intestinal epithelial barrier. This process of invasion requires a type III secretion system encoded within Salmonella pathogenicity island I (SPI1). We found that a mutant with deletions of the acetate kinase and phosphotransacetylase genes (ackA-pta) was deficient in invasion and SPI1 expression but that invasion gene expression was completely restored by supplying medium conditioned by growth of the wild-t...

  1. Prevalence of Salmonella serovars from captive reptiles from Croatia

    OpenAIRE

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

    2015-01-01

    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 bel...

  2. Rupture of popliteal arterial aneurysm due to salmonella infection

    International Nuclear Information System (INIS)

    We report here on a case of popliteal aneurysm and rupture that occurred over a 10-day period and this was all secondary to salmonella infection. Computed tomography (CT) angiography of the extremity that was performed before and after aneurysmal rupture showed the aneurysm's rapid evolution to rupture over a short period of time. We also review the pathogenesis, clinical presentation, diagnostic approach and management of salmonella aneurysms

  3. Fitness Effects of Replichore Imbalance in Salmonella enterica▿

    OpenAIRE

    Matthews, T. David; Maloy, Stanley

    2010-01-01

    A fitness cost due to imbalanced replichores has been proposed to provoke chromosome rearrangements in Salmonella enterica serovars. To determine the impact of replichore imbalance on fitness, the relative fitness of isogenic Salmonella strains containing transposon-held duplications of various sizes and at various chromosomal locations was determined. Although duplication of certain genes influenced fitness, a replichore imbalance of up to 16° did not affect fitness.

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

    OpenAIRE

    Agersø, Yvonne; Torpdahl, Mia; Zachariasen, Camilla; Seyfarth, Anne Mette; Hammerum, Anette M.; Nielsen, Eva Møller

    2012-01-01

    The objective of this research was to determine minimal inhibitory concentration (MIC) population distributions for colistin for Salmonella on subtype level. Furthermore, we wanted to determine if differences in MIC for colistin could be explained by mutations in pmrA or pmrB encoding proteins involved in processes that influence the binding of colistin to the cell membrane. During 2008–2011, 6,583 Salmonella enterica subsp. enterica isolates of human origin and 1931 isolates of animal/meat o...

  5. Prevalence of salmonella in captive reptiles from Croatia

    OpenAIRE

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

    2015-01-01

    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 bel...

  6. Salmonella enterica serotype dublin bacteraemia mimicking enteric fever

    OpenAIRE

    Dias M; Antony B; Pinto H; Rekha B.

    2009-01-01

    Salmonella enterica serotype Dublin, a bovine adapted serotype, is the commonest cause of salmonellosis in cattle. Salmonellosis in animals always presents a potential zoonotic threat. Infected cattles serves as a source of infection to humans. We present here Salmonella Dublin Bacteraemia in an elderly patient, with all the clinical details, due to the rarity of its occurrence. He was treated successfully with ciprofloxacin and his follow up period was uneventful.

  7. Accessory replicons of species of Salmonella and Shigella.

    OpenAIRE

    Dhillon, T S; Hui, Y W; Teoh-Chan, C. H.; Dhillon, E K

    1982-01-01

    Shigella and Salmonella strains isolated from clinical samples were examined. Out of 42 Shigella strains tested, 17 (40%) were found to be colicinogenic and another 3 were lysogenic. All three lysogens yielded a phage antigenically homologous to coliphage P2. Out of 30 strains tested, only 1 was found to be resistant to both neomycin and sulfamethoxazole. Out of 48 strains of Salmonella tested for drug resistance, only 2 showed multiple drug resistance. In contrast to Shigella isolates, the S...

  8. Salmonella enterica serotype dublin bacteraemia mimicking enteric fever

    Directory of Open Access Journals (Sweden)

    Dias M

    2009-01-01

    Full Text Available Salmonella enterica serotype Dublin, a bovine adapted serotype, is the commonest cause of salmonellosis in cattle. Salmonellosis in animals always presents a potential zoonotic threat. Infected cattles serves as a source of infection to humans. We present here Salmonella Dublin Bacteraemia in an elderly patient, with all the clinical details, due to the rarity of its occurrence. He was treated successfully with ciprofloxacin and his follow up period was uneventful.

  9. Isolates of Salmonella in Liguria from 2008 to 2009

    OpenAIRE

    E. Xhori; E. Rizzitelli; C. Tinteri; S. Reale; R. Bandettini; M. Molina; R. Rizzetto

    2011-01-01

    The ENTER-NET project is coordinated by the Istituto Superiore di Sanità (ISS) and includes Hospital and University loboratories from different areas of the country. This project has the aim to study the emergence and the spread of Salmonella app. isolated at a national level and to evaluate their antibiotic resitance. In the period 2008-2009 the Bacteriological Laboratory of Genoa University Department of Health Sciences (DISSAL) collected and confirmed every year about 100 Salmonella specim...

  10. Survival of Escherichia coli and Salmonella spp. in estuarine environments.

    OpenAIRE

    Rhodes, M W; Kator, H.

    1988-01-01

    Survival of Escherichia coli and Salmonella spp. in estuarine waters was compared over a variety of seasonal temperatures during in situ exposure in diffusion chambers. Sublethal stress was measured by both selective-versus-resuscitative enumeration procedures and an electrochemical detection method. E. coli and Salmonella spp. test suspensions, prepared to minimize sublethal injury, were exposed in a shallow tidal creek and at a site 7.1 km further downriver. Bacterial die-off and sublethal ...

  11. Salmonella aortitis treated with endovascular aortic repair: a case report

    OpenAIRE

    Strahm Carol; Lederer Heidi; Schwarz Esther I; Bachli Esther B

    2012-01-01

    Abstract Introduction Salmonella is a typical cause of aortitis, which is associated with high morbidity and mortality. In infrarenal disease, besides open surgery, endovascular aortic repair as an alternative treatment has been reported. To the best of our knowledge, we report the first successful endovascular aortic repair documented by necropsy to date. Case presentation A 67-year-old Caucasian man presented with low back pain, fever and positive blood cultures for Salmonella Enteritidis. ...

  12. Salmonella thomson Outbreak in a Canadian Newborn Nursery

    OpenAIRE

    Lalonde, Richard G

    1993-01-01

    Objective: To determine the mode of salmonella transmission during an outbreak in a newborn nursery.Design: Outbreak investigation with retrospective review of medical, microbiological and work records, active case-finding, and active surveillance. A case was defined as a newborn with salmonella isolated from any site.Setting: University affiliated community hospital near Montreal with 125 active care beds and 3000 deliveries annually.Patients: Cases were identified from the microbiology repo...

  13. International outbreak of Salmonella Oranienburg due to German chocolate

    OpenAIRE

    Weise Ekkehard; Bartelt Edda; Behnke Susanne C; Fisher Ian ST; Prager Rita; Roggentin Peter; Hauri Anja M; Ethelberg Steen; Fell Gerhard; van Treeck Ulrich; Feil Fabian; Dreesman Johannes; Werber Dirk; Ellis Andrea; Siitonen Anja

    2005-01-01

    Abstract Background This report describes a large international chocolate-associated Salmonella outbreak originating from Germany. Methods We conducted epidemiologic investigations including a case-control study, and food safety investigations. Salmonella (S.) Oranienburg isolates were subtyped by the use of pulsed-field gel electrophoresis (PFGE). Results From 1 October 2001 through 24 March 2002, an estimated excess of 439 S. Oranienburg notifications was registered in Germany. Simultaneous...

  14. The Role of the spv Genes in Salmonella Pathogenesis

    OpenAIRE

    Guiney, Donald G.; Fierer, Joshua

    2011-01-01

    Salmonella strains cause three main types of diseases in people: gastroenteritis, enteric (typhoid) fever, and non-typhoid extra-intestinal disease with bacteremia. Genetic analysis indicates that each clinical syndrome requires distinct sets of virulence genes, and Salmonella isolates differ in their constellation of virulence traits. The spv locus is strongly associated with strains that cause non-typhoid bacteremia, but are not present in typhoid strains. The spv region contains three gene...

  15. [Chronic Salmonella typhimurium diarrhea in an immunocompetent patient].

    Science.gov (United States)

    Mellado-Ferreiro, M; Jarne-Betrán, V; Arteaga-Mazuelas, M; Abínzano-Guillén, M L

    2016-01-01

    Chronic diarrhea caused by infection in immunocompetent patients is an infrequent condition in developed countries, although certain pathogens,generally parasites (Giardia lamblia, Isospora belli,Cryptosporidium, Cyclospora, Strongyloides, Ameba,Trichuris and Schistosoma) and some bacteria (Aeromonas,Plesiomonas, Campylobacter, Clostridium difficile, Salmonella or Mycobacterium tuberculosis)can cause persistent diarrhea.We present the case of a patient who showed Salmonella typhimurium in his stool culture and recovered following treatment with levofloxacin for 7 days. PMID:27125610

  16. Salmonella in pig lairage and in stunning box

    OpenAIRE

    Karabasil Neđeljko; Dimitrijević Mirjana; Pavlićević Nataša; Teodorović Vlado; Lončina Jasna; Nedeljković-Trailović Jelena; Baltić Milan Ž.

    2012-01-01

    Salmonella is one of the most important zoonotic pathogens and the consumption of pork meat is a major source of human infection. The aim of this study was to investigate the presence of Salmonella on different surfaces in the pig lairage and stunning box as potential sources of cross contamination of animals and carcasses. Sampling was conducted in two abattoirs (slaughterhouse A and slaughterhouse B). Samples were taken from slaughterhouse A in two instan...

  17. Direct immunoassay for detection of salmonellae in foods and feeds.

    OpenAIRE

    Anderson, J. M.; Hartman, P A

    1985-01-01

    A direct enzyme immunoassay (EIA) with polyclonal antibodies was developed for detecting salmonellae in foods and feeds. Salmonella cells were attached firmly to the wells of polystyrene microtitration plates with a capture-antibody technique. Spicer-Edwards anti-H immunoglobulin G was bound to protein A-beta-D-galactosidase to serve as the signal; 4-methylumbelliferyl-beta-D-galactoside was used as the substrate. The sensitivity threshold was 10(7) cells per ml. Direct EIA, indirect EIA, and...

  18. Ferrite attenuator modulation improves antenna performance

    Science.gov (United States)

    Hooks, J. C.; Larson, S. G.; Shorkley, F. H.; Williams, B. T.

    1970-01-01

    Ferrite attenuator inserted into appropriate waveguide reduces the gain of the antenna element which is causing interference. Modulating the ferrite attenuator to change the antenna gain at the receive frequency permits ground tracking until the antenna is no longer needed.

  19. 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.

  20. Immunomagnetic nanoparticle based quantitative PCR for rapid detection of Salmonella

    International Nuclear Information System (INIS)

    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 104 cfu.mL−1 and 103 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)

  1. Modeling of Salmonella Contamination in the Pig Slaughterhouse.

    Science.gov (United States)

    Swart, A N; Evers, E G; Simons, R L L; Swanenburg, M

    2016-03-01

    In this article we present a model for Salmonella contamination of pig carcasses in the slaughterhouse. This model forms part of a larger QMRA (quantitative microbial risk assessment) on Salmonella in slaughter and breeder pigs, which uses a generic model framework that can be parameterized for European member states, to describe the entire chain from farm-to-consumption and the resultant human illness. We focus on model construction, giving mathematical formulae to describe Salmonella concentrations on individual pigs and slaughter equipment at different stages of the slaughter process. Variability among individual pigs and over slaughterhouses is incorporated using statistical distributions, and simulated by Monte Carlo iteration. We present the results over the various slaughter stages and show that such a framework is especially suitable to investigate the effect of various interventions. In this article we present the results of the slaughterhouse module for two case study member states. The model outcome represents an increase in average prevalence of Salmonella contamination and Salmonella numbers at dehairing and a decrease of Salmonella numbers at scalding. These results show good agreement when compared to several other QMRAs and microbiological studies. PMID:26857531

  2. DNA microarray for tracing Salmonella in the feed chain.

    Science.gov (United States)

    Koyuncu, Sevinc; Andersson, Gunnar; Vos, Pieter; Häggblom, Per

    2011-03-01

    In the present study we investigated if the microarray platforms Premi®Test Salmonella (PTS) and Salmonella array (SA) could be applied for the identification and typing of Salmonella in artificially contaminated animal feed materials. The results were compared to the culture-based MSRV method and serotyping according to Kauffman-White. The SA platform showed a specificity of 100% for the identification of Salmonella compared to 93% with the PTS platform and a sensitivity of 99% or 100%, respectively. Among all identified Salmonella serotypes, 56% with the SA platform and 81% with the PTS platform were correctly identified. The difference in probe signal intensity for each probe was higher between duplicates analyzed with the SA platform than with the PTS platform. Attempts to use the microarray platforms from BPW resulted in many false negative samples and incorrect typing results. The microarray platforms tested were simple to use and might have a potential in tracing studies for Salmonella in the feed chain particularly when rapid information about serotypes are important. PMID:20688409

  3. Salmonella contamination of cereal ingredients for animal feeds.

    Science.gov (United States)

    Davies, R H; Wales, A D

    2013-10-25

    Cereal ingredients for animal feedstuffs may become contaminated by Salmonella on their farms of origin. This is often concentrated in multiple foci, owing to contamination by rodents and other wildlife which may be missed by routine sampling, and may involve serovars of particular public health significance, such as Salmonella Typhimurium (STM). The study examined such contamination in domestically-produced cereal ingredients in the United Kingdom. Cereal-producing farms with associated cattle or pig enterprises (43) and feedmills (6) were investigated, following the isolation of STM from their premises (feedmills) or STM DT104 from their livestock (farms) by routine surveillance. Cereal samples from feedmills yielded two STM isolates from the same premises, of the same phage types as were isolated from wild bird faeces at ingredient intake and product loading areas. Farm investigations identified numerous Salmonella serovars, including STM, on grain harvesting and handling equipment, in grain storage areas, and in wildlife samples. Mice were removed from one pig farm and shed Salmonella Derby and Salmonella Bovismorbificans for 10 months afterwards. Grain stores more than one kilometre away from livestock areas were rarely found to be contaminated with STM. The principal issues with Salmonella contamination of cereals appeared to be the use of livestock areas as temporary grain stores on cattle farms, and access to stored grain by wildlife and domestic animals. PMID:23915993

  4. Salmonella Typhi: from a Human Pathogen to a Vaccine Vector

    Institute of Scientific and Technical Information of China (English)

    Xiao-Lian Zhang; Victor Tunje Jeza; Qin Pan

    2008-01-01

    Salmonella (S.) typhi is an important intracellular pathogen. Among the more than 2,300 closely-related Salmonella serovars bacteria recognized, S. Typhi is the only one that is pathogenic exclusively for humans, in whom it causes typhoid or enteric fever. The pathogen has been around for many years and many studies have been done in an effort to combat it. Molecular and biologic features of S. Typhi and host factors and immune responses involved in Salmonella invasion have been extensively studies. Vaccines that have been developed most notably are Vi polysaccharide and Ty21a. However, as the results show, there is still a long way to go. It is also shown that multi-drug resistance has occurred to the few available antibiotics. More and more studies have shown that Salmonella can be used as a vaccine vector carrying antigens of other pathogens. This has been promising in that the immune system can be elicited in response to both the Salmonella bacteria and the antigen of the pathogen in question. This review aims to highlight some of the milestones attained in the fight against the disease from the time S. Typhi was seen as a pathogen causing typhoid fever to the use of Salmonella as a vaccine vector.

  5. Salmonella typhi: from a human pathogen to a vaccine vector.

    Science.gov (United States)

    Zhang, Xiao-Lian; Jeza, Victor Tunje; Pan, Qin

    2008-04-01

    Salmonella (S.) typhi is an important intracellular pathogen. Among the more than 2,300 closely-related Salmonella serovars bacteria recognized, S. typhi is the only one that is pathogenic exclusively for humans, in whom it causes typhoid or enteric fever. The pathogen has been around for many years and many studies have been done in an effort to combat it. Molecular and biologic features of S. typhi and host factors and immune responses involved in Salmonella invasion have been extensively studies. Vaccines that have been developed most notably are Vi polysaccharide and Ty21a. However, as the results show, there is still a long way to go. It is also shown that multi-drug resistance has occurred to the few available antibiotics. More and more studies have shown that Salmonella can be used as a vaccine vector carrying antigens of other pathogens. This has been promising in that the immune system can be elicited in response to both the Salmonella bacteria and the antigen of the pathogen in question. This review aims to highlight some of the milestones attained in the fight against the disease from the time S. typhi was seen as a pathogen causing typhoid fever to the use of Salmonella as a vaccine vector. PMID:18445338

  6. Prevalence of Salmonella and Staphylococcus aureus in chorizo and longaniza

    Directory of Open Access Journals (Sweden)

    Refugio Torres-Vitela

    2011-12-01

    Full Text Available Epidemiological research in developed and developing countries, had found meat products as the principal cause for foodbourne diseases. In addition, Salmonella and Staphyococcus aureus are well known pathogens for their mayor impact in public health. The objective for the present study consisted on determinate the sanitary quality from chorizo and longaniza samples from several butcheries in Guadalajara, Jalisco, Mexico. Samples of chorizo (50 and longaniza (50 were obtained from different points in Guadalajara metropolis. Presence of Salmonella and recounts for S. aureus were tested in 25 g samples. Procedure was followed according Mexican NOM 145-SSA1-1995 methods. In chorizo, 18 samples were positive to Salmonella. The count of S. aureus showed a mean of 24,600 UFC/g. On the other hand, 24 samples of longaniza were positive to Salmonella spp. In this case, the mean of S. aureus was 7,800 UFC/g. The serotypes of Salmonella spp were: Derby (30%, Adelaile (17%, Azteca (15%, Infantis (15%, Muenster(10% y Anatum (13 %. The high positivity of Salmonella spp. and S. aureus is a potential hazard to consumers.

  7. Salmonella carriers among expatriate workers in Al-Qatif area

    Directory of Open Access Journals (Sweden)

    Albreiki Hassan

    2004-01-01

    Full Text Available Background: Salmonella infection and diarrhoeal diseases are major causes of morbidity and mortality in the developing world. All expatriates applying for work permits in the Kingdom of Saudi Arabia (KSA have to undergo a governmental compulsory health check program. Aim of the study: To estimate the number of salmonella carriers who had previously been diagnosed as free of infection. Subjects and methods: Over a period of two years, a total of 17, 918 workers in Al-Qatif area, in the Eastern Province were tested for salmonella on stool samples. Results: Three hundred and twenty eight were found to be asymptomatic carriers of salmonella. The highest frequency was found among workers from Egypt (13.1 % while Filipinos and Indians were the lowest carriers (1.2%. Salmonella serogroups E, C 1 and C2 were most common ( 29%, 29% and 23.5% respectively followed by serogroups B, D and C (13%, 3.7% and 1% respectively. No Shigella species were isolated. All carriers were given antibiotics and were instructed in prophylactic hygiene measures. After completing the course of antibiotics, they were retested and found to be clear of infection. Conclusion: The health check system in this area will contribute towards the prevention of outbreaks of infection by salmonella

  8. 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 Dogs older than 24 months had higher prevalence of 61.0% and the lowest was seen in dogs aged 13-24 months (P 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. PMID:25404944

  9. Salmonella tel-el-kebir and terrapins.

    LENUS (Irish Health Repository)

    Lynch, M

    2012-02-03

    OBJECTIVES: An outbreak of Salmonella tel-el-kebir occurring over a 6-month period is described in this report. This is the first outbreak of S. tel-el-kebir in the reported literature. METHODS: S. tel-el-kebir was isolated from human faecal samples using conventional laboratory methods. RESULTS: Eight patients had S. tel-el-kebir isolated from faeces. All patients were owners of, or in close contact with, pet terrapins. The terrapins were purchased in the same pet shop, where they were imported from America. The epidemiological link with these pets was confirmed, as S. tel-el-kebir was isolated from cloacal swabs from the terrapins, and from terrapin water. Molecular biology studies using DNA amplification fingerprinting (DAF) gave identical fingerprint patterns for all human and terrapin isolates. CONCLUSIONS: Salmonellosis associated with exotic pets is a re-emerging disease in the 1990s, and measures to reduce this are discussed.

  10. Experimental Salmonella typhimurium infections in rats. I

    DEFF Research Database (Denmark)

    Hougen, H P; Jensen, E T; Klausen, B

    1989-01-01

    The course of experimentally induced Salmonella typhimurium infection was studied in three groups of inbred LEW rats: homozygous +/+, athymic rnu/rnu and isogeneic thymus-grafted rnu/rnu rats. In the first experiment the animals were inoculated intraperitoneally with 10(8) bacteria and all animals...... very low in the athymic nude animals. Polyclonal antibody production was only observed in the euthymic animals and only regarding IgG. Athymic rats were not able to clear the infection, while the thymus-grafted animals reacted like euthymic rats: Very few animals housed the bacteria four weeks after...... inoculation, and no bacteria could be detected after four months. Immunohistochemical studies of lymphoid organs revealed that the infection caused a drop in the percentages of T non-helper cells, indicating low suppressor activity. The study shows that athymic nude rats are well suited for studies of...

  11. ENHANCEMENTS TO NATURAL ATTENUATION: SELECTED CASE STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K; W. H. Albright, W; E. S. Becvar, E; C. H. Benson, C; T. O. Early, T; E. Hood, E; P. M. Jardine, P; M. Lorah, M; E. Majche, E; D. Major, D; W. J. Waugh, W; G. Wein, G; O. R. West, O

    2007-05-15

    In 2003 the US Department of Energy (DOE) embarked on a project to explore an innovative approach to remediation of subsurface contaminant plumes that focused on introducing mechanisms for augmenting natural attenuation to achieve site closure. Termed enhanced attenuation (EA), this approach has drawn its inspiration from the concept of monitored natural attenuation (MNA).

  12. Conservation of Salmonella typhimurium virulence plasmid maintenance regions among Salmonella serovars as a basis for plasmid curing.

    OpenAIRE

    Tinge, S A; Curtiss, R

    1990-01-01

    The association of large plasmids with virulence in invasive Salmonella serovars has led to a number of studies designed to uncover the role of these plasmids in virulence. This study addresses two aspects of virulence-associated plasmids. The first is the distribution of the replication and maintenance regions among the plasmids of different Salmonella serovars, and the second is the use of the conserved virulence plasmid par region to provide a rapid method for eliminating the virulence pla...

  13. Hybrid hepatitis B virus core-pre-S proteins synthesized in avirulent Salmonella typhimurium and Salmonella typhi for oral vaccination.

    OpenAIRE

    Schödel, F; Kelly, S M; Peterson, D L; Milich, D R; Curtiss, R

    1994-01-01

    Avirulent salmonellae expressing foreign genes are attractive for use as oral vaccine carriers. To facilitate the stable expression of heterologous genes without conferring antibiotic resistance, a deletion of the asdA1 gene was introduced into Salmonella typhimurium and S. typhi delta cya delta crp mutant vaccine strains. An asd-complementing plasmid expressing hybrid hepatitis B virus nucleocapsid-pre-S (HBcAg-pre-S) particles was constructed. These hybrid HBcAg-pre-S particle genes were st...

  14. The Principle of Salmonellae Contamination in Poultry Meat and Methods of Control in Processing%鸡禽肉受沙门氏菌污染的机制和加工中的控制方法

    Institute of Scientific and Technical Information of China (English)

    庄荣玉; 黄耀文

    2002-01-01

    The poultry processing industry is going to be modernized more rapidly than before in China in recent years. Therefore, the chance of the processed poultry meat carrying the food pathogen is increased. The principle of salmonellae contamination in poultry occurring in hatcheries, transport containers and processing plants, etc. were elucidated in this article. The useful methods to control the salmonellae contamination in poultry in the food industry were also introduced. Using live, attenuated salmonellae vaccine could produce a salmonellae-free bird. The contamination by salmonellae could be reduced to zero by using this new method. These methods could further guide improvements in the processing techniques of poultry meat. Also, it could reduce the human foodborne infection through ingestion of poultry meat containing salmonellae.%随着中国经济的迅速发展,鸡肉屠宰加工业日趋现代化,也使加工后的鸡肉携带食物病原菌的机会增多.本文从食品加工的角度,论述了鸡在孵化、运输和深度加工过程中受沙门氏菌污染的机制,提出了现代食品加工业中控制沙门氏菌污染鸡肉的几种方法,以及使用疫苗培养无沙门氏菌感染的活的鸡群,使鸡从根本上摆脱受沙门氏菌的感染,对鸡禽肉的深度加工技术具有一定的指导意义.

  15. Isolamento de Salmonella Braenderup em arara-azul (Anodorhynchus hyacinthinus Salmonella Braenderup isolation in Hyacinth macaw (Anodorhynchus hyacinthinus

    Directory of Open Access Journals (Sweden)

    Mariangela Costa Allgayer

    2009-11-01

    Full Text Available O monitoramento sanitário de populações de arara-azul (Anodorhynchus hyacinthinus de vida livre visa a permitir ajustes de manejo em ambiente natural alterado. Para avaliar a ocorrência de Salmonella spp. em filhotes dessa espécie, foram coletados swabs de cloaca no Pantanal de Miranda, Mato Grosso do Sul (MS. Uma colônia morfológica e bioquimicamente compatível com Salmonella spp. foi isolada e sorotipada como Salmonella Braenderup. Devido ao alto potencial zoonótico desse microrganismo, é importante o controle sanitário de psitacídeos em vida livre. Na literatura pesquisada não foi encontrado relato sobre o isolamento dessa bactéria em arara-azul, tanto em vida livre, como em cativeiro.The sanitary monitoring of free-living Hyacinth macaw (Anodorhynchus hyacinthinus allows adjusting the management in altered natural habitat. To evaluate the occurrence of Salmonella spp. it was collected cloacal swabs of this nestlings species, in the Pantanal wetlands, in the state of Mato Grosso do Sul, Brazil. One Salmonella-like colony was serologically typed and identified as Salmonella Braenderup. Due to the high zoonotical potential of this microorganism, it is important an effective sanitary control of wildlife psittacines. In the literature searched it was not found any report on isolation of this bacterium in Hyacinth macaw for both free-living and captive animals.

  16. Protection Against Necrotic Enteritis in Broiler Chickens by Regulated Delayed Lysis Salmonella Vaccines.

    Science.gov (United States)

    Jiang, Yanlong; Mo, Hua; Willingham, Crystal; Wang, Shifeng; Park, Jie-Yeun; Kong, Wei; Roland, Kenneth L; Curtiss, Roy

    2015-12-01

    Necrotic enteritis (NE), caused by Gram-positive Clostridium perfringens type A strains, has gained more attention in the broiler industry due to governmental restrictions affecting the use of growth-promoting antibiotics in feed. To date, there is only one commercial NE vaccine available, based on the C. perfringens alpha toxin. However, recent work has suggested that the NetB toxin, not alpha toxin, is the most critical virulence factor for causing NE. These findings notwithstanding, it is clear from prior research that immune responses against both toxins can provide some protection against NE. In this study, we delivered a carboxyl-terminal fragment of alpha toxin and a GST-NetB fusion protein using a novel attenuated Salmonella vaccine strain designed to lyse after 6-10 rounds of replication in the chicken host. We immunized birds with vaccine strains producing each protein individually, a mixture of the two strains, or with a single vaccine strain that produced both proteins. Immunization with strains producing either of the single proteins was not protective, but immunization with a mixture of the two or with a single strain producing both proteins resulted in protective immunity. The vaccine strain synthesizing both PlcC and GST-NetB was able to elicit strong production of intestinal IgA, IgY, and IgM antibodies and significantly protect broilers against C. perfringens challenge against both mild and severe challenges. Although not part of our experimental plan, the broiler chicks we obtained for these studies were apparently contaminated during transit from the hatchery with group D Salmonella. Despite this drawback, the vaccines worked well, indicating applicability to real-world conditions. PMID:26629620

  17. Comparison of a PCR serotyping assay, Check&Trace assay for Salmonella, and Luminex Salmonella serotyping assay for the characterization of Salmonella enterica identified from fresh and naturally contaminated cilantro.

    Science.gov (United States)

    Jean-Gilles Beaubrun, J; Ewing, L; Jarvis, K; Dudley, K; Grim, C; Gopinath, G; Flamer, M-L; Auguste, W; Jayaram, A; Elmore, J; Lamont, M; McGrath, T; Hanes, D E

    2014-09-01

    Salmonella enterica isolated from fresh cilantro samples collected through the USDA/AMS Microbiological Data Program (MDP) were used to compare a PCR serotyping assay against the Check&Trace assay and the Luminex (BioPlex) Salmonella serotyping assay. The study was conducted to evaluate the effectiveness of the three methods for serotyping Salmonella from both enrichment broth cultures and pure Salmonella cultures. In this investigation, Salmonella spp. serotyping was conducted using 24 h enrichment broth cultures and pure Salmonella cultures from cilantro samples, with the PCR serotyping assay. Conversely, the Check&Trace and Luminex for Salmonella assays required pure cultures for Salmonella serotyping. The cilantro samples contained S. enterica serovar Montevideo, Newport, Saintpaul, and Tennessee, identified by the PCR serotyping assay and Check&Trace for Salmonella, but the Luminex assay only identified two of the four serotypes of the cilantro samples. The anticipated impact from this study is that the PCR serotyping assay provides a time- and cost-effective means for screening, identifying and serotyping Salmonella using DNA extracted from 24 h enrichment cilantro samples. PMID:24929735

  18. Survival and Growth of Epidemically Successful and Nonsuccessful Salmonella enterica Clones after Freezing and Dehydration

    DEFF Research Database (Denmark)

    Müller, Karoline; Aabo, Søren; Birk, Tina;

    2012-01-01

    Salmonella isolates were characterized as successful or nonsuccessful. We studied the survival and growth of stationary- and exponential-phase cells of these isolates after freezing for up to 336 days in minced meat. We also investigated survival and growth after dehydration at 10°C and 82% relative humidity...... temperature were less harmful to Salmonella than were low humidity and high temperature. Tolerance to adverse conditions was highest for Salmonella Infantis and one Salmonella Typhimurium U292 isolate and lowest for Salmonella Derby and one Salmonella Typhimurium DT170 isolate. Dehydration, in contrast to...... freezing, was differently tolerated by the Salmonella strains in this study, but tolerance to freezing and dehydration does not appear to contribute to the emergence of successful Salmonella clones....

  19. Identification and characterization of multidrug-resistant Salmonella enterica serotype Albert isolates in the United States

    Science.gov (United States)

    Salmonella enterica is one of the most common causes of bacterial foodborne illness in the United States. Although most Salmonella infections are self-limiting, antimicrobial treatment is critical for invasive salmonellosis. Primary antimicrobial treatment options include fluoroquinolones or extende...

  20. MICROBIALLY MEDIATED GROWTH SUPPRESSION AND DEATH OF SALMONELLA IN COMPOSTED SEWAGE SLUDGE

    Science.gov (United States)

    The role of compost microflora in the suppression of salmonella regrowth in composted sewage sludge was investigated. Microbial inhibition studies of salmonella growth were conducted on nutrient agar, in composts that had been subjected to different temperatures in compost piles,...

  1. 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.

  2. EFFECT OF THE ANTIMUTAGENS VANILLIN AND CINNAMALDEHYDE ON THE SPONTANEOUS MUTATION SPECTRA OF SALMONELLA TA104

    Science.gov (United States)

    Effect of the Antimutagens Vanillin and Cinnamaldehyde on the / Spontaneous Mutation Spectra of Salmonella TAlO4 Vanillin (VAN) and cinnamaldehyde (CIN) are dietary antimutagens that, when added to assay plates, reduced the spontaneous mutant frequency in Salmonella typhi...

  3. 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......-Salmonella strains, 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....... 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...

  4. Attenuation in silica-based optical fibers

    DEFF Research Database (Denmark)

    Wandel, Marie Emilie

    2006-01-01

    absorption peaks in order to investigate the cause of an unusual high attenuation in a series of transmission fibers. Strong indications point to Ni2+ in octahedral coordination as being the cause of the high attenuation. The attenuation of fibers having a high core refractive index is analyzed and the cause...... well as the viscosity profile a lower attenuation of high index fibers can be obtained. The design of dispersion compensating fibers using the super mode approach is described, the object being to design dispersion compensating fibers for dispersion compensating fiber modules having a low attenuation......, described by a high figure of merit. The major trade offs encountered when designing dispersion compensating fibers with high figure of merit are to obtain a very negative dispersion, low attenuation and low micro bend loss at the same time. The model for predicting the attenuation of high index fibers is...

  5. Removal of the phage-shock protein PspB causes reduction of virulence in Salmonella enterica serovar Typhimurium independently of NRAMP1

    DEFF Research Database (Denmark)

    Wallrodt, Inke; Jelsbak, Lotte; Thomsen, Line E.;

    2014-01-01

    The phage-shock protein (Psp) system is believed to manage membrane stress in all Enterobacteriaceae and has recently emerged as being important for virulence in several pathogenic species of this phylum. The core of the Psp system consists of the pspA-D operon and the distantly located pspG gene....... In Salmonella enterica serovar Typhimurium (S. Typhimurium), it has recently been reported that PspA is essential for systemic infection of mice, but only in NRAMP1(+) mice, signifying that attenuation is related to coping with divalent cation starvation in the intracellular environment. In the...... present study, we investigated the contribution of individual psp genes to virulence of S. Typhimurium. Interestingly, deletion of the whole pspA-D set of genes caused attenuation in both NRAMP1(+) and NRAMP1(-) mice, indicating that one or more of the psp genes contribute to virulence independently of...

  6. Efficient and Rapid Detection of Salmonella Using Microfluidic Impedance Based Sensing

    OpenAIRE

    Shibajyoti Ghosh Dastider; Syed Barizuddin; Nuh S. Yuksek; Majed Dweik; Mahmoud F. Almasri

    2015-01-01

    We present a low cost, easy to fabricate biosensor, which can quickly and accurately detect Salmonella typhimurium. This study also compares the advantages of the microfluidic biosensor over a nonmicrofluidic biosensor. High density interdigitated electrode array was used to detect Salmonella cells inside a microfluidic chip. Monoclonal anti-Salmonella antibodies were allowed to be immobilized on the surface of the electrode array for selective detection of Salmonella typhimurium. An impedanc...

  7. Toward Molecular Level of the “Salmonella-Victim” Ecology, Genetics, and Evolution

    OpenAIRE

    Rumyantsev, S.N.

    2004-01-01

    Bacteria of the Salmonella genus are polypathogenic agents that can affect both men and animals, causing devastating and fatal illness. Despite considerable immunological, epidemiological, and genetic efforts, and increased understanding of how the Salmonella infection develops, many key questions concerning Salmonella infection remain unanswered. Salmonella can be carried as harmless commensals in some sectors of the population. In some individuals, however, the same microbes cause illness w...

  8. Resistance to antibiotics and genotype characteristics of Salmonella enterica subspecies enterica serovar Mbandaka isolated from poultry

    OpenAIRE

    Vidanović Dejan; Sabo Z.; Kilibarda Nataša; Živadinović Mira; Žarković Aleksandar; Matović Kazimir

    2008-01-01

    Salmonellas are one of the main zoonotic pathogens whose reservoirs are poultry, cattle and pigs. By means of the food chain salmonellas can be transferred to humans through contaminated food of animal origin. Multiresistant strains Salmonella are particularly dangerous since they can transfer genes of resistance to antibiotics to other microorganisms. Control of salmonellas primarily depends on a good surveillance system and knowledge of the strain types present in the epizootiologic area. I...

  9. Monoclonal antibodies delineate multiple epitopes on the O antigens of Salmonella typhi lipopolysaccharide.

    OpenAIRE

    Qadri, A; S. K. Gupta; Talwar, G P

    1988-01-01

    Fifteen monoclonal antibodies (MAbs) directed against Salmonella typhi were produced and characterized. The specificities of the antibodies were determined by their binding patterns in an enzyme immunoassay, with a panel of lipopolysaccharides isolated from different bacteria. Seven MAbs reacted with S. typhi, Salmonella enteritidis, and Salmonella dublin (all belonging to serogroup D). One MAb also reacted with Salmonella paratyphi A and S. paratyphi B. Five MAbs reacted with S. typhi, S. en...

  10. Geographical distribution of salmonella infected pig, cattle and sheep herds in Sweden 1993-2010

    OpenAIRE

    Skog Lars; Lewerin Susanna; Frössling Jenny; Wahlström Helene

    2011-01-01

    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, catt...

  11. Genetic Requirements for Salmonella-Induced Cytopathology in Human Monocyte-Derived Macrophages

    OpenAIRE

    Browne, Sara H; Lesnick, Marc L.; Guiney, Donald G.

    2002-01-01

    Infection of human macrophages with Salmonella enterica serovar Typhimurium or Salmonella enterica serovar Dublin produces delayed cytotoxicity characterized by cell detachment and associated apoptosis. Using a site-specific mutant in the SpvB active site, we verify that the ADP-ribosylation activity of SpvB is required for delayed cytotoxicity in human macrophages infected with Salmonella. SipB and the type III protein secretion system (TTSS) encoded by Salmonella pathogenicity island 1 (SPI...

  12. Enzyme-linked immunosorbent assay for detection of Salmonella lipopolysaccharide in poultry specimens.

    OpenAIRE

    Rigby, C E

    1984-01-01

    An enzyme-linked immunosorbent assay (ELISA) for detection of salmonellae was developed and evaluated by using artificially contaminated specimens of poultry feed, feces, litter, or carcass rinsings, and naturally contaminated water samples. Specimens containing salmonellae of serogroups B or C2 inhibited the binding of polyvalent anti-O serum to microtiter plate wells coated with lipopolysaccharide of Salmonella typhimurium (serogroup B) or Salmonella albany (serogroup C2), respectively. Tre...

  13. Control of a Salmonella Virulence Locus by an ATP-Sensing Leader mRNA

    OpenAIRE

    Lee, Eun-Jin; Groisman, Eduardo A.

    2012-01-01

    The facultative intracellular pathogen Salmonella enterica resides within a membrane-bound compartment inside macrophages 1. This compartment must be acidified for Salmonella to survive within macrophages 2, possibly because acid pH promotes expression of Salmonella virulence proteins 3,4. We reasoned that Salmonella may sense its surroundings have turned acidic not only upon protonation of the extracytoplasmic domain of a protein sensor 5 but also by an increase in cytosolic ATP levels becau...

  14. Risks Involved in the Use of Enrofloxacin for Salmonella Enteritidis or Salmonella Heidelberg in Commercial Poultry

    Science.gov (United States)

    Morales-Barrera, Eduardo; Calhoun, Nicole; Lobato-Tapia, Jose L.; Lucca, Vivian; Prado-Rebolledo, Omar; Hernandez-Velasco, Xochitl; Merino-Guzman, Ruben; Petrone-García, Victor M.; Latorre, Juan D.; Mahaffey, Brittany D.; Teague, Kyle D.; Graham, Lucas E.; Wolfenden, Amanda D.; Baxter, Mikayla F. A.; Hargis, Billy M.; Tellez, Guillermo

    2016-01-01

    The objectives of the present study were to evaluate the risks involved in the use of Enrofloxacin for Salmonella Enteritidis (SE) or Salmonella Heidelberg (SH) in commercial poultry and determine the effects of a probiotic as an antibiotic alternative. Two experiments were conducted to evaluate the risks involved in the use of Enrofloxacin for SE or SH in commercial poultry. Experiment 1 consisted of two trials. In each trial, chickens were assigned to one of three groups; control + SE challenged; Enrofloxacin 25 mg/kg + SE; and Enrofloxacin 50 mg/kg + SE. Chickens received Enrofloxacin in the drinking water from days 1 to 5 of age. On day 6, all groups received fresh water without any treatment. All chickens were orally gavaged with 107 cfu/chick of SE at 7 days of age and euthanized on 8 days of age. In Experiment 2, turkey poults were assigned to one of the three groups; control + SH; probiotic + SH; and Enrofloxacin 50 mg/kg + SH. Poults received probiotic or Enrofloxacin in the drinking water from days 1 to 5 of age. On day 6, poults received fresh water without any treatment. Poults were orally gavaged with 107 cfu/poult of SH at 7 days of age. Poults were weighed and humanely killed 24 h post-SH challenge to evaluate serum concentration of fluorescein isothiocyanate-dextran to evaluate intestinal permeability, metagenomics, and SH infection. In both trials of Experiment 1, chickens treated with Enrofloxacin were more susceptible to SE organ invasion and intestinal colonization when compared with control non-treated chickens (P < 0.05). In Experiment 2, poults treated with 50 mg/kg of Enrofloxacin showed an increase in body weight, however, this group also showed an increase in SH susceptibility, intestinal permeability, and lower proportion of Firmicutes and Bacteroidetes, but with control group had the highest proportion of Proteobacteria. By contrast, poults that received the probiotic had the highest

  15. Salmonella em carcaças de frango congeladas Salmonella in broiler frozen carcasses

    OpenAIRE

    Débora Martins Silva Santos; Angelo Berchieri Junior; Suely Aparecida Fernandes; Ana Terezinha Tavechio; Luiz Augusto do Amaral

    2000-01-01

    Um total de 150 carcaças de frango congeladas, de quatro marcas comerciais, foram analisadas para pesquisa de Salmonella. Foram examinadas 43 carcaças de cada uma das marcas A, B, D e 21 da marca C. Observou-se um percentual de 32,0% de contaminação. Foram identificados 11 sorotipos: S. Agona, S. Anatum, S. Enteritidis, S. Hadar, S. Havana, S. Mbandaka, S. Montevideo, S. Ouakam, S. Poona, S. Schwarzengrund e S. I 4, 5, 12: -. O antibiograma das cepas mostrou 100% de resistência à ampicilina, ...

  16. 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.

  17. A Phylogenetic and Phenotypic Analysis of Salmonella enterica Serovar Weltevreden, an Emerging Agent of Diarrheal Disease in Tropical Regions.

    Science.gov (United States)

    Makendi, Carine; Page, Andrew J; Wren, Brendan W; Le Thi Phuong, Tu; Clare, Simon; Hale, Christine; Goulding, David; Klemm, Elizabeth J; Pickard, Derek; Okoro, Chinyere; Hunt, Martin; Thompson, Corinne N; Phu Huong Lan, Nguyen; Tran Do Hoang, Nhu; Thwaites, Guy E; Le Hello, Simon; Brisabois, Anne; Weill, François-Xavier; Baker, Stephen; Dougan, Gordon

    2016-02-01

    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. PMID:26867150

  18. 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.

  19. Survival of Salmonella enterica in aerated and nonaerated wastewaters from dairy lagoons

    Science.gov (United States)

    Salmonella is the most commonly identified foodborne pathogen in produce, meat and poultry. Cattle are known reservoirs of Salmonella and the pathogen excreted in feces end up in manure flush lagoons. Salmonella enterica survival was monitored in wastewater from on-site holding lagoons equipped with...

  20. Spatial surveillance during control of infectious diseases – Salmonella Dublin in Denmark 2002-2009

    DEFF Research Database (Denmark)

    Ersbøll, Annette Kjær; Nielsen, Liza Rosenbaum

    2010-01-01

    Salmonella Dublin is the most commonly isolated Salmonella serotype in Danish cattle and leads to economic and welfare losses in infected herds. Furthermore, it leads to high mortality in human cases. A national surveillance program for Salmonella Dublin was initiated in Denmark in October 2002. ...

  1. 9 CFR 147.11 - Laboratory procedure recommended for the bacteriological examination of salmonella.

    Science.gov (United States)

    2010-01-01

    ... the bacteriological examination of salmonella. 147.11 Section 147.11 Animals and Animal Products... procedure recommended for the bacteriological examination of salmonella. (a) For egg- and meat-type chickens... 25 birds, and birds from Salmonella enteritidis (SE) positive environments should be cultured...

  2. Effect of 60Co γ-ray irradiation on salmonella in high immunity egg yolk

    International Nuclear Information System (INIS)

    Salmonella were inoculated into the yolk and irradiated with different dose of 60Co γ-ray. The results show that 3 kGy irradiation dose can kill all Salmonella in the yolk and D10 value of Salmonella in the yolk is 0.36-0.46 kGy

  3. Electron-beam-inactivated vaccine against Salmonella enteritidis colonization in molting hens

    Science.gov (United States)

    Electron Beam (eBeam) ionization technology has a variety of applications in modern society. The underlying hypothesis was that electron beam (eBeam) inactivated Salmonella enterica serovar Enteritidis (SE) cells can serve as a vaccine to control Salmonella colonization and Salmonella shedding in c...

  4. Reduced salmonella fecal shedding in swine administered porcine granulocyte-colony stimulating factor (G-CSF)

    Science.gov (United States)

    Salmonella colonization of food animals is a concern for animal health, food safety and public health. Key objectives of pre-harvest food safety programs are to detect asymptomatic Salmonella carriage in food animals, reduce colonization, and prevent transmission of Salmonella to other animals and ...

  5. Inactivation of Salmonella on tomato stem scars by acidic sanitizing solutions

    Science.gov (United States)

    Tomato stem scars are a likely contamination point for Salmonella, although they are recalcitrant to decontamination. Investigating stem scar sanitation may represent a worst-case-scenario model for inactivating Salmonella from externally-contaminated tomatoes. A composite of Salmonella Saintpau...

  6. 78 FR 42526 - Compliance Policy Guide Sec. 690.800 Salmonella

    Science.gov (United States)

    2013-07-16

    ... HUMAN SERVICES Food and Drug Administration Compliance Policy Guide Sec. 690.800 Salmonella in Food for... ``Compliance Policy Guide Sec. 690.800 Salmonella in Food for Animals'' (the CPG). The CPG provides guidance to... the availability of a guidance document entitled ``Compliance Policy Guide Sec. 690.800 Salmonella...

  7. Gastrointestinal microbiota and porcine immunity: factors that influence salmonella shedding in swine

    Science.gov (United States)

    Pigs are often asymptomatically colonized with the human foodborne pathogen Salmonella and can exhibit notable variation in severity and duration of Salmonella fecal shedding. Multiple factors impact the dynamics of Salmonella in swine, including features of the microorganism, responses from the pi...

  8. 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.

  9. Split Marketing as a Risk Factor for Salmonella Enterica Infection in Swine

    Science.gov (United States)

    On-farm reduction of Salmonella prevalence in pigs requires the identification of risk factors to direct interventions. This study was designed to determine if split marketing of finishing pigs constitutes a risk factor for Salmonella infections, by comparing Salmonella prevalence in the first group...

  10. Comparison of microbial communities isolated from feces of asymptomatic Salmonella-shedding and non-Salmonella shedding dairy cows

    Directory of Open Access Journals (Sweden)

    Bradd J. Haley

    2016-06-01

    Full Text Available In the United States Salmonella enterica subsp. enterica serotypes Kentucky and Cerro are frequently isolated from asymptomatic dairy cows. However, factors that contribute to colonization of the bovine gut by these two serotypes have not been identified. To investigate associations between Salmonella status and bacterial diversity, as well as the diversity of the microbial community in the dairy cow hindgut, the bacterial and archaeal communities of fecal samples from cows on a single dairy farm were determined by high-throughput sequencing of 16S rRNA gene amplicons. Fecal grab samples were collected from two Salmonella-positive cows and two Salmonella-negative cows on five sampling dates (n = 20 cows, and 16S rRNA gene amplicons from these samples were sequenced on the Illumina MiSeq platform. A high level of alpha (within and beta diversity (between samples demonstrated that microbial profiles of dairy cow hindguts are quite diverse. To determine whether Salmonella presence, sampling year, or sampling date explained a significant amount of the variation in microbial diversity, we performed constrained ordination analyses (distance based RDA on the unifrac distance matrix produced with QIIME. Results indicated that there was not a significant difference in the microbial diversity associated with Salmonella presence (P > 0.05, but there were significant differences between sampling dates and years (Pseudo-F= 2.157 to 4.385, P < 0.05. Based on these data, it appears that commensal Salmonella infections with serotypes Cerro and Kentucky in dairy cows have little or no association with changes in the abundance of major bacterial groups in the hindgut. Rather, our results indicated that temporal dynamics and other undescribed parameters associated with them were the most influential drivers of the differences in microbial diversity and community structure in the dairy cow hindgut.

  11. Imaging Rayleigh wave attenuation with USArray

    Science.gov (United States)

    Bao, Xueyang; Dalton, Colleen A.; Jin, Ge; Gaherty, James B.; Shen, Yang

    2016-07-01

    The EarthScope USArray provides an opportunity to obtain detailed images of the continental upper mantle at an unprecedented scale. The majority of mantle models derived from USArray data to date contain spatial variations in seismic-wave speed; however, in many cases these data sets do not by themselves allow a non-unique interpretation. Joint interpretation of seismic attenuation and velocity models can improve upon the interpretations based only on velocity and provide important constraints on the temperature, composition, melt content, and volatile content of the mantle. The surface wave amplitudes that constrain upper-mantle attenuation are sensitive to factors in addition to attenuation, including the earthquake source excitation, focusing and defocusing by elastic structure, and local site amplification. Because of the difficulty of isolating attenuation from these other factors, little is known about the attenuation structure of the North American upper mantle. In this study, Rayleigh wave traveltime and amplitude in the period range 25-100 s are measured using an interstation cross-correlation technique, which takes advantage of waveform similarity at nearby stations. Several estimates of Rayleigh wave attenuation and site amplification are generated at each period, using different approaches to separate the effects of attenuation and local site amplification on amplitude. It is assumed that focusing and defocusing effects can be described by the Laplacian of the traveltime field. All approaches identify the same large-scale patterns in attenuation, including areas where the attenuation values are likely contaminated by unmodelled focusing and defocusing effects. Regionally averaged attenuation maps are constructed after removal of the contaminated attenuation values, and the variations in intrinsic shear attenuation that are suggested by these Rayleigh wave attenuation maps are explored.

  12. Serum Bactericidal Assay: New Role in Salmonella Detection.

    Science.gov (United States)

    Chen, Yu; Wu, Da; Sun, Min; Deng, Mingjun; Cui, Shuhua; Liang, Chengzhu; Geng, Juan; Sun, Tao; Long, Ling; Xiao, Xizhi

    2016-01-01

    While inspecting animal feed for Salmonella contamination, we routinely observed bacterial colonies on selective agars that were similar in appearance to those formed by Salmonella. These were identified as Citrobacter freundii, Proteus mirabilis, and Serratia fonticola using biochemical and serological techniques. Because the presence of these bacterial species confounds identification of Salmonella, we refer to them as "interference bacteria." Polyvalent antisera against these interference bacteria were prepared by immunizing rabbits with a mixture of all three organisms. To minimize or eliminate interference by these bacteria, the polyvalent antisera were introduced between the steps of selective enrichment and Salmonella-selective plating. The antisera raised against the interference bacteria, when combined with neonatal rabbit complement, exhibited specific bactericidal activity against C. freundii, P. mirabilis, and S. fonticola. The respective serum bactericidal assay titers were 2(9), 2(8), and 2(10). In selective broth, polyvalent antisera could also kill the target bacterial cells effectively. We tested 526 samples (186 white fishmeal, 97 red fishmeal, and 243 cattle bone powder) using the polyvalent antisera and found that the rates of contamination of each species of the three respective foods decreased by 58.8, 100, and 83%. Our data indicates that polyvalent sera against C. freundii, P. mirabilis, and S. fonticola can be used as inhibitors to increase the accuracy of Salmonella detection. PMID:26822285

  13. Protein Chips for Detection of Salmonella spp. from Enrichment Culture.

    Science.gov (United States)

    Poltronieri, Palmiro; Cimaglia, Fabio; De Lorenzis, Enrico; Chiesa, Maurizio; Mezzolla, Valeria; Reca, Ida Barbara

    2016-01-01

    Food pathogens are the cause of foodborne epidemics, therefore there is a need to detect the pathogens in food productions rapidly. A pre-enrichment culture followed by selective agar plating are standard detection methods. Molecular methods such as qPCR have provided a first rapid protocol for detection of pathogens within 24 h of enrichment culture. Biosensors also may provide a rapid tool to individuate a source of Salmonella contamination at early times of pre-enrichment culture. Forty mL of Salmonella spp. enrichment culture were processed by immunoseparation using the Pathatrix, as in AFNOR validated qPCR protocols. The Salmonella biosensor combined with immunoseparation showed a limit of detection of 100 bacteria/40 mL, with a 400 fold increase to previous results. qPCR analysis requires processing of bead-bound bacteria with lysis buffer and DNA clean up, with a limit of detection of 2 cfu/50 μL. Finally, a protein chip was developed and tested in screening and identification of 5 common pathogen species, Salmonella spp., E. coli, S. aureus, Campylobacter spp. and Listeria spp. The protein chip, with high specificity in species identification, is proposed to be integrated into a Lab-on-Chip system, for rapid and reproducible screening of Salmonella spp. and other pathogen species contaminating food productions. PMID:27110786

  14. The relationship between the numbers of Salmonella Enteritidis, Salmonella Heidelberg, or Salmonella Hadar colonizing reproductive tissues of experimentally infected laying hens and deposition inside eggs

    Science.gov (United States)

    Contamination of eggs by Salmonella Enteritidis has been a prominent cause of human illness for several decades and is the focus of a recently implemented national regulatory plan for egg-producing flocks in the United States. S. Heidelberg has also been identified as an egg-transmitted pathogen. Th...

  15. The effect of source herd and abattoir factors on pig carcass Salmonella contamination evaluated by multilevel modelling

    DEFF Research Database (Denmark)

    Baptista, Filipa Matos; Dahl, Jan; Nielsen, Liza Rosenbaum

    2010-01-01

    In Denmark, a Surveillance-and-Control Programme for Salmonella in pigs has been in place for several years. This study investigated factors associated with Salmonella pig carcass contamination, namely estimated daily number of Salmonella seropositive pigs delivered to slaughter, average Salmonella...... methods, such as abattoir hygiene, logistic slaughter and decontamination, adjusting for the Danish herd and abattoir structure....

  16. T- and B-cell immune responses of patients who had undergone colectomies to oral administration of Salmonella enterica serovar Typhi Ty21a vaccine.

    Science.gov (United States)

    Kilhamn, Jan; Lundin, Samuel B; Brevinge, Hans; Svennerholm, Ann-Mari; Jertborn, Marianne

    2003-05-01

    The capacity of an oral live attenuated Salmonella enterica serovar Typhi Ty21a vaccine to induce immune responses in patients who had undergone colectomies because of ulcerative colitis was evaluated, and these responses were compared with those of healthy volunteers. Purified CD4(+) and CD8(+) T cells from peripheral blood were stimulated in vitro by using the heat-killed Ty21a vaccine strain, and the proliferation and gamma interferon (IFN-gamma) production were measured before and 7 or 8 days after vaccination. Salmonella-specific immunoglobulin A (IgA) and IgG antibody responses in serum along with IgA antibody responses in ileostomy fluids from the patients who had undergone colectomies were also evaluated. Three doses of vaccine given 2 days apart failed to induce proliferative T-cell responses in all the six patients who had undergone colectomies, and increases in IFN-gamma production were found only among the CD8(+) cells from three of the patients. In contrast, both proliferative responses and increased IFN-gamma production were observed among CD4(+) and CD8(+) T cells from 3 and 6 of 10 healthy volunteers, respectively. Salmonella-specific IgA and/or IgG antibody responses in serum were observed for five (56%) of nine patients who had undergone colectomies and in 15 (88%) of 17 healthy volunteers. In ileostomy fluids, significant anti-Salmonella IgA antibody titer increases were detected in six (67%) of nine patients who had undergone colectomies. The impaired T- and B-cell immune responses found after vaccination in the circulation of patients who have undergone colectomies may be explained by a diminished colonization of the Ty21a vaccine strain due to the lack of a terminal ileum and colon. PMID:12738643

  17. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  18. Reorganization of the endosomal system in Salmonella-infected cells: the ultrastructure of Salmonella-induced tubular compartments.

    Directory of Open Access Journals (Sweden)

    Viktoria Krieger

    2014-09-01

    Full Text Available 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.

  19. Prolonged inhibition of bacterial protein synthesis abolishes Salmonella invasion.

    Science.gov (United States)

    MacBeth, K J; Lee, C A

    1993-01-01

    We have found that prolonged inhibition of bacterial protein synthesis abolishes the ability of Salmonella typhimurium to enter HEp-2 cells. Our results suggest that an essential invasion factor has a functional half-life that is seen as a gradual loss of invasiveness in the absence of protein synthesis. Therefore, Salmonella invasiveness appears to be a transient phenotype that is lost unless protein synthesis is maintained. This finding may explain why salmonellae grown to stationary phase lose their ability to enter cultured cells. In addition, a short-lived capacity to enter cells may be important during infection so that bacterial invasiveness is limited to certain times and host sites during pathogenesis. PMID:8454361

  20. Organic acids for control of Salmonella in different feed materials

    DEFF Research Database (Denmark)

    Koyuncu, Sevinc; Andersson, Mats Gunnar; Löfström, Charlotta;

    2013-01-01

    FA, propionic acid (PA) and sodium formate (SF) was investigated. Four Salmonella strains isolated from feed were assayed for their acid tolerance. Also, the effect of lower temperatures (5°C and 15°C) compared to room temperature was investigated in rape seed and soybean meal. Results The efficacy....... Typhimurium. The tolerance of the S. Infantis strain compared with the S. Typhimurium strain was statistically significant (p<0.05). The lethal effect of FA on the S. Typhimurium strain and the S. Infantis strain was lower at 5°C and 15°C compared to room temperatures. Conclusions Acid treatment of Salmonella...... tolerance between different Salmonella strains, and the treatment temperature....

  1. A retrospective study on salmonella infection in Danish broiler flocks

    DEFF Research Database (Denmark)

    Angen, Øystein; Skov, M. N.; Chriél, Mariann; Agger, J. F.; Bisgaard, M.

    A retrospective longitudinal study was conducted to identify risk factors associated with Salmonella enterica infection in Danish broiler production. The study was based on information in the antemortem database (AM database) where data were available for all broiler Becks slaughtered over the 2......-year period from 1992 to 1993 in Denmark. The AM database contains information collected by the ante-mortem veterinarians, from the slaughterhouses, and from the salmonella examinations carried out at the National Veterinary Laboratory. The epidemiological unit was the individual broiler flock. The...... been evaluated. Fourteen variables were selected for analysis by multivariable logistic regression. An increased risk of salmonella infection in the broiler Becks was associated with the biggest hatcheries and feedmill, with an increasing number of houses on the farm, if the preceding flock was...

  2. RECURRENT SALMONELLA TYPHI CHEST WALL ABSCESSES IN A DIABETIC LADY

    Directory of Open Access Journals (Sweden)

    Jayasri Helen

    2014-09-01

    Full Text Available : Salmonella enterica serovar typhi causing typhoid fever is common in many parts of the world particularly in developing countries. Extra intestinal manifestations are uncommon and occur in immunocompromised individuals such as patients with diabetes, HIV infection, chronic steroid use, chemotherapy and malignancy. We report a case of Salmonella typhi causing recurrent chest wall abscesses in a lady with uncontrolled diabetes. She was admitted with high grade fever, left sided chest wall abscess and a previous history of two similar chest wall abscesses. After hospitalization prompt incision and drainage was done and aerobic culture of pus grew moderate growth of Salmonella typhi resistant to ciprofloxacin and sensitive to cephalosporins. Based on culture report our patient was treated with oral azithromycin for ten days and parenteral ceftriaxone for six weeks. There was rapid and full recovery and six months follow up revealed no recurrence.

  3. Phosphorylation of the autophagy receptor optineurin restricts Salmonella growth

    DEFF Research Database (Denmark)

    Wild, Philipp; Farhan, Hesso; McEwan, David G; Wagner, Sebastian; Rogov, Vladimir V; Brady, Nathan R; Richter, Benjamin; Korac, Jelena; Waidmann, Oliver; Choudhary, Chunaram; Dötsch, Volker; Bumann, Dirk; Dikic, Ivan

    2011-01-01

    Selective autophagy can be mediated via receptor molecules that link specific cargoes to the autophagosomal membranes decorated by ubiquitin-like microtubule-associated protein light chain 3 (LC3) modifiers. Although several autophagy receptors have been identified, little is known about mechanisms...... controlling their functions in vivo. In this work, we found that phosphorylation of an autophagy receptor, optineurin, promoted selective autophagy of ubiquitin-coated cytosolic Salmonella enterica. The protein kinase TANK binding kinase 1 (TBK1) phosphorylated optineurin on serine-177, enhancing LC3 binding...... affinity and autophagic clearance of cytosolic Salmonella. Conversely, ubiquitin- or LC3-binding optineurin mutants and silencing of optineurin or TBK1 impaired Salmonella autophagy, resulting in increased intracellular bacterial proliferation. We propose that phosphorylation of autophagy receptors might...

  4. Salmonella Dublin i oksekød, 2014

    OpenAIRE

    Aabo, Søren; Hansen, Tina Beck

    2015-01-01

    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 krydskon...

  5. Control of salmonella in meat and meat products by irradiation

    International Nuclear Information System (INIS)

    This paper highlights the importance of food irradiation in the protection of the public against food poisoning from eating meat or meat products contaminated with salmonella. Salmonella infections are increasing at an alarming rate (2000 in 1952 to 12000 reported cases in 1982 in England and Wales alone). Dr. Dempster reports that 50% of the chicken carcasses examined by workers in America were found to be salmonella contaminated. Use of irradiation in conjunction with mild refrigeration can extend the shelf-life of vacuum packed chicken by a factor of three. Important legislation now under discussion in the U.S.A. is likely to extend the applicability of food irradiation rapidly in the near future

  6. Neonatal outbreak of salmonella worthington in a general hospital

    Directory of Open Access Journals (Sweden)

    Muley V

    2004-01-01

    Full Text Available This is a report of an outbreak of Salmonella worthington in neonates at Sassoon General Hospitals, Pune, which occurred during August and September 2000. A total of 148 blood, 4 CSF and 6 stool specimens were received from neonates admitted to the hospital. Salmonella worthington could be isolated from 17 clinical specimens [15 blood (10.8%, 1 CSF (25% and 1 stool (16.6% sample]. Environmental swabs were also processed. An attempt was made to detect carriers in health care personnel. However, no source or carrier of Salmonella worthington in the hospital environment could be identified. Intensive cleaning measures and fumigation were undertaken. All these measures succeeded in aborting the outbreak.

  7. The dynamics of Salmonella occurrence in commercial laying hen flocks throughout a laying period

    DEFF Research Database (Denmark)

    Schulz, J.; Van Hoorebeke, S.; Hald, Birthe;

    2011-01-01

    of a laying period. The total of 41 laying hen flocks*18 in Belgium, six in Denmark and 17 in Germany*were followed during an entire laying period. Samples taken from the empty cleaned and disinfected poultry houses were all negative for Salmonella. After hens arrived on the farms, five pooled faecal...... up to three times positive for Salmonella. Forty-three out of 50 positive samples contained Salmonella Enteritidis phage type 4 (29 isolates) or phage type 8 (14 isolates). The probability of subsequent Salmonella-positive findings increased significantly in Salmonella-positive flocks (PB0.05, odds...

  8. Salmonella prevalence among reptiles in a zoo education setting.

    Science.gov (United States)

    Hydeskov, H B; Guardabassi, L; Aalbaek, B; Olsen, K E P; Nielsen, S S; Bertelsen, M F

    2013-06-01

    Clinically healthy reptiles may shed Salmonella and therefore act as a potential zoonotic threat. Most people in Northern European countries are rarely exposed to reptiles, but many zoos have education departments where children have direct contact with this group of animals. The objectives of this study were to determine the prevalence and serotype distribution of Salmonella among reptiles in the Education Department (n = 55) at Copenhagen Zoo and compare it to the Zoo's main reptile collection (n = 145) to evaluate the zoonotic risk. Salmonella was isolated from cloacal swabs by selective enrichment, and a single isolate from each positive sample was further identified by biochemical tests and serotyped. The overall prevalence was 35% (69/200) with significant difference between the Education Department (64%, 35/55) and the main reptile collection (23%, 34/145). A total of 28 serotypes were detected. Ten serotypes were isolated from more than one specimen and four from more than one species. Salmonella enterica subsp. enterica serovar Eastbourne was the predominant serotype (32%, 22/69) and was also the serotype isolated from most reptile species (n = 7). Transmission of serotypes from one department to another was very limited indicated by the serotype distribution. Despite the relative high prevalence observed among the reptiles in the Zoo's Education Department compared to the reptiles in the Zoo's main reptile collection, no Salmonella cases have been linked to the Zoo, and Salmonella ser. Eastbourne is very rarely isolated from humans in Denmark. Simple hygienic procedures such as hand washing which is consistently carried out following handling of reptiles at the Education Department may reduce the risk and therefore contribute to this low prevalence. PMID:22835051

  9. Phenotypic and Genotypic Diversity of Salmonella in Finishing Swine.

    Science.gov (United States)

    Pires, Alda F A; Funk, Julie A; Habing, Greg G; Bolin, Carole

    2016-04-01

    Salmonella enterica (nontyphoidal) is one of the major causes of foodborne diseases in the United States and worldwide. Molecular typing methods are significant tools used to better understand the transmission and ecology of Salmonella in order to implement pre-harvest control measures. The objectives of this study were to describe the Salmonella genotypes, the distribution of isolate subtypes from different ecological niches (i.e., barn environment, nursery, and individual pigs) and their evolution over time in a longitudinal study conducted in three finishing sites (housing pigs from 10 weeks of age until slaughter at 24-26 weeks of age). Among the 107 Salmonella isolates submitted for pulsed-field gel electrophoresis (PFGE) analysis, there were 25 distinct subtypes. PFGE genotyping results were consistent with the serotype findings. A large number of distinguishable PFGE patterns (i.e., within the same serovar) were observed and different combinations of subtypes were identified within and across sites and cohorts. New subtypes may result of the introduction of new strains, genetic changes, or ongoing transmission of evolved strains within the production system. The same subtypes were detected intermittently during the study period, which suggests the persistence of indistinguishable subtypes in this production system. In addition, this study suggests persistence of the same subtype over several cohorts of pigs and potential residual contamination from the barn. Factors affecting adaptation and transmission of Salmonella within and among ecological systems (e.g., finishing pigs, nursery, and environment) should be further investigated. Understanding genotypic diversity of Salmonella in different ecological niches during pre-harvest may contribute to the development of more targeted and cost effective control programs during nursery and finishing phases. PMID:26977814

  10. Multiple host kinases contribute to Akt activation during Salmonella infection.

    Directory of Open Access Journals (Sweden)

    Bernhard Roppenser

    Full Text Available SopB is a type 3 secreted effector with phosphatase activity that Salmonella employs to manipulate host cellular processes, allowing the bacteria to establish their intracellular niche. One important function of SopB is activation of the pro-survival kinase Akt/protein kinase B in the infected host cell. Here, we examine the mechanism of Akt activation by SopB during Salmonella infection. We show that SopB-mediated Akt activation is only partially sensitive to PI3-kinase inhibitors LY294002 and wortmannin in HeLa cells, suggesting that Class I PI3-kinases play only a minor role in this process. However, depletion of PI(3,4 P2/PI(3-5 P3 by expression of the phosphoinositide 3-phosphatase PTEN inhibits Akt activation during Salmonella invasion. Therefore, production of PI(3,4 P2/PI(3-5 P3 appears to be a necessary event for Akt activation by SopB and suggests that non-canonical kinases mediate production of these phosphoinositides during Salmonella infection. We report that Class II PI3-kinase beta isoform, IPMK and other kinases identified from a kinase screen all contribute to Akt activation during Salmonella infection. In addition, the kinases required for SopB-mediated activation of Akt vary depending on the type of infected host cell. Together, our data suggest that Salmonella has evolved to use a single effector, SopB, to manipulate a remarkably large repertoire of host kinases to activate Akt for the purpose of optimizing bacterial replication in its host.

  11. Quinolone Resistance Mechanisms Among Salmonella enterica in Malaysia.

    Science.gov (United States)

    Thong, Kwai Lin; Ngoi, Soo Tein; Chai, Lay Ching; Teh, Cindy Shuan Ju

    2016-06-01

    The prevalence of quinolone-resistant Salmonella enterica is on the rise worldwide. Salmonella enterica is one of the major foodborne pathogens in Malaysia. Therefore, we aim to investigate the occurrence and mechanisms of quinolone resistance among Salmonella strains isolated in Malaysia. A total of 283 Salmonella strains isolated from food, humans, and animals were studied. The disk diffusion method was used to examine the quinolone susceptibility of the strains, and the minimum inhibitory concentration (MIC) values of nalidixic acid and ciprofloxacin were also determined. DNA sequencing of the quinolone resistance-determining regions (QRDRs) of gyrase and topoisomerase IV genes and the plasmid-borne qnr genes was performed. The transfer of the qnr gene was examined through transconjugation experiment. A total of 101 nalidixic acid-resistant Salmonella strains were identified. In general, all strains were highly resistant to nalidixic acid (average MICNAL, 170 μg/ml). Resistance to ciprofloxacin was observed in 30.7% of the strains (1 ≤ MICCIP ≤ 2 μg/ml). Majority of the strains contained missense mutations in the QRDR of gyrA (69.3%). Silent mutations were frequently detected in gyrB (75.2%), parC (27.7%), and parE (51.5%) within and beyond the QRDRs. Novel mutations were detected in parC and parE. The plasmid-borne qnrS1 variant was found in 36.6% of the strains, and two strains were found to be able to transfer the qnrS1 gene. Overall, mutations in gyrA and the presence of qnrS1 genes might have contributed to the high level of quinolone resistance among the strains. Our study provided a better understanding on the status of quinolone resistance among Salmonella strains circulating in Malaysia. PMID:26683630

  12. Differential dust attenuation in CALIFA galaxies

    Science.gov (United States)

    Vale Asari, N.; Cid Fernandes, R.; Amorim, A. L.; Lacerda, E. A. D.; Schlickmann, M.; Wild, V.; Kennicutt, R. C.

    2016-06-01

    Dust attenuation has long been treated as a simple parameter in SED fitting. Real galaxies are, however, much more complicated: The measured dust attenuation is not a simple function of the dust optical depth, but depends strongly on galaxy inclination and the relative distribution of stars and dust. We study the nebular and stellar dust attenuation in CALIFA galaxies, and propose some empirical recipes to make the dust treatment more realistic in spectral synthesis codes. By adding optical recombination emission lines, we find better constraints for differential attenuation. Those recipes can be applied to unresolved galaxy spectra, and lead to better recovered star formation rates.

  13. HLA-B27-Transfected (Salmonella Permissive) and HLA-A2-Transfected (Salmonella Nonpermissive) Human Monocytic U937 Cells Differ in Their Production of Cytokines

    OpenAIRE

    Ekman, Päivi; Saarinen, Marja; He, Qiushui; Gripenberg-Lerche, Christel; Grönberg, Alvar; Arvilommi, Heikki; Granfors, Kaisa

    2002-01-01

    The cytokine secretion of the Salmonella-permissive, HLA-B27-positive U937 cells was examined, as it was previously shown that these cells kill Salmonella less efficiently than controls. Salmonella-permissive U937 cells showed upregulated production of interleukin 10 and to a lesser extent tumor necrosis factor alpha. HLA-B27-associated modulation of cytokine responses may have importance in the pathogenesis of reactive arthritis.

  14. Genome Sequences of Salmonella enterica Serovar Heidelberg Isolates Isolated in the United States from a Multistate Outbreak of Human Salmonella Infections

    OpenAIRE

    Hoffmann, Maria; Luo, Yan; Lafon, Patricia C.; Timme, Ruth; Allard, Marc W.; McDermott, Patrick F.; Brown, Eric W.; Zhao, Shaohua

    2013-01-01

    Salmonella enterica is recognized as one of the most common bacterial agents of foodborne illness. We report draft genomes of four Salmonella serovar Heidelberg isolates associated with the recent multistate outbreak of human Salmonella Heidelberg infections linked to kosher broiled chicken livers in the United States in 2011. Isolates 2011K-1259 and 2011K-1232 were recovered from humans, whereas 2011K-1724 and 2011K-1726 were isolated from chicken liver. Whole genome sequence analysis of the...

  15. Vibrio spp. and Salmonella spp., presence and susceptibility in crabs Ucides cordatus Vibrio spp. e Salmonella spp. em caranguejos, Ucides cordatus

    OpenAIRE

    Regine H.S.F. Vieira; Elenice Araújo de Lima; Dannielle Batista Rolim Sousa; Eliane Falavina dos Reis; Renata Garcia Costa; Dália dos Prazeres Rodrigues

    2004-01-01

    The presence of Vibrio spp. and Salmonella spp. in crabs marketed at the Bezerra de Menezes Ave., Fortaleza, State of Ceará, Brazil, was assessed between February and May, 2003. The number of individuals sampled in each one of the fifteen weekly samplings ranged between four and eight. Seven strains of Salmonella, from four different samplings, were identified, being five of them identified as serotype S. Senftenberg and two as S. Poona. All strains of Salmonella were sensitive to the tested ...

  16. Identification by PCR of Non-typhoidal Salmonella enterica Serovars Associated with Invasive Infections among Febrile Patients in Mali

    OpenAIRE

    Tennant, Sharon M.; Diallo, Souleymane; Levy, Haim; Livio, Sofie; Sow, Samba O.; Tapia, Milagritos; Fields, Patricia I.; Mikoleit, Matthew; Tamboura, Boubou; Kotloff, Karen L.; Nataro, James P; Galen, James E.; Levine, Myron M.

    2010-01-01

    Background 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. Methods We have extended a previously developed series of polymerase ...

  17. 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

    Full Text Available BACKGROUND: 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. METHODS: 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. PRINCIPAL FINDINGS: 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. CONCLUSION: We have described a simple yet effective PCR method to support surveillance of the incidence of invasive disease caused by NTS in developing countries.

  18. Elimination of Salmonella in Poultry with Ionizing Radiation

    International Nuclear Information System (INIS)

    The radiation resistance of S. typhimurium in comminuted chicken meat was not affected by the breed of poultry (three different breeds tested) or by the type of meat (white or dark). A factor which did influence radio-resistance was the temperature during irradiation. A difference in radio-resistance was noted among five Salmonella serotypes tested. S.oranienburg was the most resistant and S.newport was the least resistant whereas S. thompson, S.heidelberg and S. typhimurium were intermediate. Of the salmonellae which survived irradiation in the non-frozen state, only an insignificant number were inactivated during subsequent quick-freezing and the concentration remained relatively constant over a three-month storage period at 0°F, Thus, salmonellae that have been irradiated (in chicken meat) do not appear to be any more susceptible to freezing injury compared with non-irradiated salmonellae. The psychrophiles in comminuted whole chicken meat surviving irradiation (300 krad) were a mixture of yeasts and members of the Achromobacter-Alicaligenes group. In quantitating salmonellae surviving irradiation in chicken meat by the plate count method, the greatest recovery was obtained with tryptic soy yeast extract agar. Selective media such as brilliant-green sulphadiazene agar, bismuth sulphite agar and MacConkey agar gave good recovery, but with Salmonella- Shigella agar or desoxycholate citrate agar results were poor. Recovery on brilliant green-sulphadiazene agar was enhanced by the addition of yeast extract. Enumeration of salmonellae in irradiated chicken by the ''most probable numbers'' method was comparable with results obtained by plate count. Satisfactory results were obtained with selenite cystine broth. Pre-enrichment into various nutrient broths before inoculation into a selective broth medium did not appear to enhance recovery. Repeated irradiation and sub-culturing of survivors produced a population of Salmonella with increased radio-resistance. Cells in

  19. Automated 5 ' nuclease PCR assay for identification of Salmonella enterica

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Ahrens, Peter; Rådström, P.

    2000-01-01

    A simple and ready-to-go test based on a 5' nuclease (TaqMan) PCR technique was developed for identification of presumptive Salmonella enterica isolates. The results were compared with those of conventional methods. The TaqMan assay was evaluated for its ability to accurately detect 210 S. enterica...... Salmonella strains tested resulted in positive FAM and TET signals. In addition, it was found that the complete PCR mixture, predispensed in microwell plates, could be stored for up to 3 months at -20 degrees C, Thus, the diagnostic TaqMan assay developed can be a useful and simple alternative method for...

  20. Salmonella from gopher tortoises (Gopherus polyphemus) in south Georgia.

    Science.gov (United States)

    Lockhart, J Mitchell; Lee, Gregory; Turco, Jenifer; Chamberlin, Linda

    2008-10-01

    From 2002 to 2006, gopher tortoises (Gopherus polyphemus) were collected at Moody Air Force Base, Lowndes/Lanier counties, Georgia, USA, and opportunistically surveyed for the presence of Salmonella species. Four of 155 (2.6%) cloacal swabs collected from 80 tortoises were positive for the presence of Salmonella enterica, and the following serovars were identified: Give, Hartford, Javiana, and Luciana. Female tortoises (5%) were infected at a rate similar to male tortoises (5%). All isolates were obtained from adult tortoises (n = 73); subadults (n = 7) were all negative. Each isolated serovar is a potential human pathogen, suggesting appropriate precautions should be emphasized when handling these animals. PMID:18957656