Sample records for cronobacter sakazakii baa-894

  1. Immunoproteomic identification of immunogenic proteins in Cronobacter sakazakii strain BAA-894.

    PubMed

    Wang, Jian; Du, Xin-Jun; Lu, Xiao-Nan; Wang, Shuo

    2013-03-01

    Cronobacter spp. are emerging opportunistic pathogens. Cronobacter sakazakii is considered as the predominant species in all infections. So far, our understanding of the species' immunogens and potential virulence factors of Cronobacter spp. remains limited. In this study, an immunoproteomic approach was used to investigate soluble and insoluble proteins from the genome-sequenced strain C. sakazakii ATCC BAA-894. Proteins were separated using two-dimensional electrophoresis, detected by Western blotting with polyclonal antibodies of C. sakazakii BAA-894, and identified using tandem mass spectrometry (MALDI-MS and MALDI-MS/MS, MS/MSMS). A total of 11 immunoreactive proteins were initially identified in C. sakazakii BAA-894, including two outer membrane proteins, four periplasmic proteins, and five cytoplasmic proteins. In silico functional analysis of the 11 identified proteins indicated three proteins that were initially described as immunogens of pathogenic bacteria. For the remaining eight proteins, one protein was categorized as a potential virulence factor involved in protection against reactive oxygen species, and seven proteins were considered to play potential roles in adhesion, invasion, and biofilm formation. To our knowledge, this is the first time that immunogenic proteins of C. sakazakii BAA-894 have been identified as immunogens and potential virulence factors by an immunoproteomics approach. Future studies should investigate the roles of these proteins in bacterial pathogenesis and modulation of host immune responses during infection to identify their potential as molecular therapeutic targets.

  2. Characterization of the phosphate-specific transport system in Cronobacter sakazakii BAA-894.

    PubMed

    Liang, X; Hu, X; Wang, X; Wang, J; Fang, Y; Li, Y

    2017-09-01

    Characterize the phosphate-specific transport system in Cronobacter sakazakii BAA-894. The genes relevant to phosphate transfer in C. sakazakii BAA-894 were determined by using sequence alignment to the corresponding genes in Escherichia coli. Then, the determined pst operon in C. sakazakii BAA-894 was deleted using the lambda Red recombination system. Using the wild type C. sakazakii BAA-894 as a control, the membrane permeability, auto-aggregation, exopolysaccharide biosynthesis, biofilm formation, and adhesion ability of the mutant ▵pst grown in media containing high or low concentrations of phosphate were investigated; stronger auto-aggregation, less biofilm formation and higher adhesion ability were observed in ▵pst cells grown in low phosphate media. Transcriptome analysis showed that phosphate availability has a global influence to C. sakazakii BAA-894 and ▵pst cells. Phosphorus availability is important for C. sakazakii in many ways including biofilm formation and adhesion ability. This study demonstrates that phosphate availability has a global influence to C. sakazakii, expends our understanding to the phosphate transfer in C. sakazakii, and is helpful for revealing the survival mechanism of C. sakazakii under stress conditions. © 2017 The Society for Applied Microbiology.

  3. Genome Sequence of Cronobacter sakazakii BAA-894 and Comparative Genomic Hybridization Analysis with Other Cronobacter Species

    PubMed Central

    Kucerova, Eva; Clifton, Sandra W.; Xia, Xiao-Qin; Long, Fred; Porwollik, Steffen; Fulton, Lucinda; Fronick, Catrina; Minx, Patrick; Kyung, Kim; Warren, Wesley; Fulton, Robert; Feng, Dongyan; Wollam, Aye; Shah, Neha; Bhonagiri, Veena; Nash, William E.; Hallsworth-Pepin, Kymberlie; Wilson, Richard K.

    2010-01-01

    Background The genus Cronobacter (formerly called Enterobacter sakazakii) is composed of five species; C. sakazakii, C. malonaticus, C. turicensis, C. muytjensii, and C. dublinensis. The genus includes opportunistic human pathogens, and the first three species have been associated with neonatal infections. The most severe diseases are caused in neonates and include fatal necrotizing enterocolitis and meningitis. The genetic basis of the diversity within the genus is unknown, and few virulence traits have been identified. Methodology/Principal Findings We report here the first sequence of a member of this genus, C. sakazakii strain BAA-894. The genome of Cronobacter sakazakii strain BAA-894 comprises a 4.4 Mb chromosome (57% GC content) and two plasmids; 31 kb (51% GC) and 131 kb (56% GC). The genome was used to construct a 387,000 probe oligonucleotide tiling DNA microarray covering the whole genome. Comparative genomic hybridization (CGH) was undertaken on five other C. sakazakii strains, and representatives of the four other Cronobacter species. Among 4,382 annotated genes inspected in this study, about 55% of genes were common to all C. sakazakii strains and 43% were common to all Cronobacter strains, with 10–17% absence of genes. Conclusions/Significance CGH highlighted 15 clusters of genes in C. sakazakii BAA-894 that were divergent or absent in more than half of the tested strains; six of these are of probable prophage origin. Putative virulence factors were identified in these prophage and in other variable regions. A number of genes unique to Cronobacter species associated with neonatal infections (C. sakazakii, C. malonaticus and C. turicensis) were identified. These included a copper and silver resistance system known to be linked to invasion of the blood-brain barrier by neonatal meningitic strains of Escherichia coli. In addition, genes encoding for multidrug efflux pumps and adhesins were identified that were unique to C. sakazakii strains from

  4. Transcriptome analysis of Cronobacter sakazakii ATCC BAA-894 after interaction with human intestinal epithelial cell line HCT-8.

    PubMed

    Jing, Chun-e; Du, Xin-jun; Li, Ping; Wang, Shuo

    2016-01-01

    Cronobacter spp. are opportunistic pathogens that are responsible for infections including severe meningitis, septicemia, and necrotizing enterocolitis in neonates and infants. To date, questions still remain regarding the mechanisms of pathogenicity and virulence determinants for each bacterial strain. In this study, we established an in vitro model for Cronobacter sakazakii ATCC BAA-894 infection of HCT-8 human colorectal epithelial cells. The transcriptome profile of C. sakazakii ATCC BAA-894 after interaction with HCT-8 cells was determined using high-throughput whole-transcriptome sequencing (RNA sequencing (RNA-seq)). Gene expression profiles indicated that 139 genes were upregulated and 72 genes were downregulated in the adherent C. sakazakii ATCC BAA-894 strain on HCT-8 cells compared to the cultured bacteria in the cell-free medium. Expressions of some flagella genes and virulence factors involved in adherence were upregulated. High osmolarity and osmotic stress-associated genes were highly upregulated, as well as genes responsible for the synthesis of lipopolysaccharides and outer membrane proteins, iron acquisition systems, and glycerol and glycerophospholipid metabolism. In sum, our study provides further insight into the mechanisms underlying C. sakazakii pathogenesis in the human gastrointestinal tract.

  5. Analysis on pathogenic and virulent characteristics of the Cronobacter sakazakii strain BAA-894 by whole genome sequencing and its demonstration in basic biology science.

    PubMed

    Bao, Xuerui; Yang, Ling; Chen, Lequn; Li, Bing; Li, Lin; Li, Yanyan; Xu, Zhenbo

    2017-08-01

    Cronobacter sakazakii is an opportunistic pathogen responsible for necrotizing enterocolitis, meningitis and septicaemia especially to infant and neonate, with high lethality ranging in 40%-80%. This strain is able to survive in infant milk formula and possesses capability of pathogenicity and virulence, biofilm formation, and high resistance to elevated osmotic, low pH, heat, oxidation, and desiccasion. This study is aims to investigate the molecular characteristics of Cronobacter sakazakii BAA 894, including mechanisms of its invasion and adherence, biofilm formation, unusual resistance to environmental stress employing whole genome sequencing and comparative genomics. Results in this study suggest that numerous genes and pathways, such as LysM, Cyx system, luxS, vancomycin resistance pathway, insulin resistance pathway, and sod encoding superoxide dismutase for the survival of C. sakazakii in macrophages, contribute to pathogenicity and resistance to stressful environment of C. sakazakii BAA 894. Copyright © 2017. Published by Elsevier Ltd.

  6. Outer membrane defect and stronger biofilm formation caused by inactivation of a gene encoding for heptosyltransferase I in Cronobacter sakazakii ATCC BAA-894.

    PubMed

    Wang, L; Hu, X; Tao, G; Wang, X

    2012-05-01

    To investigate the role of lipopolysaccharide (LPS) structure in the stability of outer membrane and the ability of biofilm formation in Cronobacter sakazakii. A C. sakazakii mutant strain LWW02 was constructed by inactivating the gene ESA_04107 encoding for heptosyltransferase I. LPS were purified from LWW02, and changes in their structure were confirmed by thin-layer chromatography and electrospray ionization mass spectrometry. Comparing with the wild-type strain BAA-894, slower growth, higher membrane permeability, higher surface hydrophobicity, stronger ability of autoaggregation and biofilm formation were observed for the mutant strain LWW02. The gene ESA_04107 encodes heptosyltransferase I in C. sakazakii ATCC BAA-894. The cleavage of LPS in C. sakazakii could cause its outer membrane defects and increase its ability to form biofilms. The study is important for understanding the pathogenic mechanism and efficient control of C. sakazakii. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  7. Microarray-based Comparative Genomic Indexing of the Cronobacter genus (Enterobacter sakazakii)

    USDA-ARS?s Scientific Manuscript database

    Cronobacter is a recently defined genus synonymous with Enterobacter sakazakii. This new genus currently comprises 6 genomospecies. To extend our understanding of the genetic relationship between Cronobacter sakazakii BAA-894 and the other species of this genus, microarray-based comparative genomi...

  8. Protein sequences insight into heavy metal tolerance in Cronobacter sakazakii BAA-894 encoded by plasmid pESA3.

    PubMed

    Chaturvedi, Navaneet; Kajsik, Michal; Forsythe, Stephen; Pandey, Paras Nath

    2015-12-01

    The recently annotated genome of the bacterium Cronobacter sakazakii BAA-894 suggests that the organism has the ability to bind heavy metals. This study demonstrates heavy metal tolerance in C. sakazakii, in which proteins with the heavy metal interaction were recognized by computational and experimental study. As the result, approximately one-fourth of proteins encoded on the plasmid pESA3 are proposed to have potential interaction with heavy metals. Interaction between heavy metals and predicted proteins was further corroborated using protein crystal structures from protein data bank database and comparison of metal-binding ligands. In addition, a phylogenetic study was undertaken for the toxic heavy metals, arsenic, cadmium, lead and mercury, which generated relatedness clustering for lead, cadmium and arsenic. Laboratory studies confirmed the organism's tolerance to tellurite, copper and silver. These experimental and computational study data extend our understanding of the genes encoding for proteins of this important neonatal pathogen and provide further insights into the genotypes associated with features that can contribute to its persistence in the environment. The information will be of value for future environmental protection from heavy toxic metals.

  9. A phosphoethanolamine transferase specific for the 4'-phosphate residue of Cronobacter sakazakii lipid A.

    PubMed

    Liu, L; Li, Y; Wang, X; Guo, W

    2016-11-01

    Investigate how Cronobacter sakazakii modify their lipid A structure to avoid recognition by the host immune cells. Lipid A modification was observed in C. sakazakii BAA894 grown at pH 5·0 but not pH 7·0. Overexpression of C. sakazakii gene ESA_RS09200 in Escherichia coli W3110 caused a phosphoethanolamine (PEA) modification of lipid A; when ESA_RS09200 was deleted in C. sakazakii BAA894, this lipid A modification disappeared. Lipid A modification was observed in BAA894 grown at pH 5·0 when the 1- phosphate residue of lipid A was removed, but disappeared when the 4'- phosphate residue of lipid A was removed. When ESA_RS16430, the orthologous gene of E. coli pmrA, was deleted in C. sakazakii BAA894, this PEA modification of lipid A was still observed, suggesting that this modification was not regulated by the PmrA-PmrB system. Compared to the wild-type BAA894, ESA_RS09200 deletion mutant showed decreased resistance to cationic antimicrobial peptides (CAMP), increased recognition by TLR4/MD2, decreased ability to invade and persist in mammalian cells. ESA_RS09200 in C. sakazakii BAA894 encodes a PEA transferase that specifically adds a PEA to the 4'-phosphate residue of lipid A, but not regulated by the PmrA-PmrB system. PEA modification of lipid A reduces recognition and killing by the host innate immune system. This study showed that modification of the lipid A moiety of C. sakazakii with PEA increased resistance to CAMP and recognition of the immune response although signalling of TLR4/MD2 cascade, suggesting that the organism could not successfully evade the host innate immune system without the transference of PEA to its lipid A moiety. © 2016 The Society for Applied Microbiology.

  10. Complete genome sequence and phenotype microarray analysis of Cronobacter sakazakii SP291: a persistent isolate cultured from a powdered infant formula production facility.

    PubMed

    Yan, Qiongqiong; Power, Karen A; Cooney, Shane; Fox, Edward; Gopinath, Gopal R; Grim, Christopher J; Tall, Ben D; McCusker, Matthew P; Fanning, Séamus

    2013-01-01

    Outbreaks of human infection linked to the powdered infant formula (PIF) food chain and associated with the bacterium Cronobacter, are of concern to public health. These bacteria are regarded as opportunistic pathogens linked to life-threatening infections predominantly in neonates, with an under developed immune system. Monitoring the microbiological ecology of PIF production sites is an important step in attempting to limit the risk of contamination in the finished food product. Cronobacter species, like other microorganisms can adapt to the production environment. These organisms are known for their desiccation tolerance, a phenotype that can aid their survival in the production site and PIF itself. In evaluating the genome data currently available for Cronobacter species, no sequence information has been published describing a Cronobacter sakazakii isolate found to persist in a PIF production facility. Here we report on the complete genome sequence of one such isolate, Cronobacter sakazakii SP291 along with its phenotypic characteristics. The genome of C. sakazakii SP291 consists of a 4.3-Mb chromosome (56.9% GC) and three plasmids, denoted as pSP291-1, [118.1-kb (57.2% GC)], pSP291-2, [52.1-kb (49.2% GC)], and pSP291-3, [4.4-kb (54.0% GC)]. When C. sakazakii SP291 was compared to the reference C. sakazakii ATCC BAA-894, which is also of PIF origin, the annotated genome data identified two interesting functional categories, comprising of genes related to the bacterial stress response and resistance to antimicrobial and toxic compounds. Using a phenotypic microarray (PM), we provided a full metabolic profile comparing C. sakazakii SP291 and the previously sequenced C. sakazakii ATCC BAA-894. These data extend our understanding of the genome of this important neonatal pathogen and provides further insights into the genotypes associated with features that can contribute to its persistence in the PIF environment.

  11. Complete genome sequence and phenotype microarray analysis of Cronobacter sakazakii SP291: a persistent isolate cultured from a powdered infant formula production facility

    PubMed Central

    Yan, Qiongqiong; Power, Karen A.; Cooney, Shane; Fox, Edward; Gopinath, Gopal R.; Grim, Christopher J.; Tall, Ben D.; McCusker, Matthew P.; Fanning, Séamus

    2013-01-01

    Outbreaks of human infection linked to the powdered infant formula (PIF) food chain and associated with the bacterium Cronobacter, are of concern to public health. These bacteria are regarded as opportunistic pathogens linked to life-threatening infections predominantly in neonates, with an under developed immune system. Monitoring the microbiological ecology of PIF production sites is an important step in attempting to limit the risk of contamination in the finished food product. Cronobacter species, like other microorganisms can adapt to the production environment. These organisms are known for their desiccation tolerance, a phenotype that can aid their survival in the production site and PIF itself. In evaluating the genome data currently available for Cronobacter species, no sequence information has been published describing a Cronobacter sakazakii isolate found to persist in a PIF production facility. Here we report on the complete genome sequence of one such isolate, Cronobacter sakazakii SP291 along with its phenotypic characteristics. The genome of C. sakazakii SP291 consists of a 4.3-Mb chromosome (56.9% GC) and three plasmids, denoted as pSP291-1, [118.1-kb (57.2% GC)], pSP291-2, [52.1-kb (49.2% GC)], and pSP291-3, [4.4-kb (54.0% GC)]. When C. sakazakii SP291 was compared to the reference C. sakazakii ATCC BAA-894, which is also of PIF origin, the annotated genome data identified two interesting functional categories, comprising of genes related to the bacterial stress response and resistance to antimicrobial and toxic compounds. Using a phenotypic microarray (PM), we provided a full metabolic profile comparing C. sakazakii SP291 and the previously sequenced C. sakazakii ATCC BAA-894. These data extend our understanding of the genome of this important neonatal pathogen and provides further insights into the genotypes associated with features that can contribute to its persistence in the PIF environment. PMID:24032028

  12. Cpa, the outer membrane protease of Cronobacter sakazakii, activates plasminogen and mediates resistance to serum bactericidal activity.

    PubMed

    Franco, A A; Kothary, M H; Gopinath, G; Jarvis, K G; Grim, C J; Hu, L; Datta, A R; McCardell, B A; Tall, B D

    2011-04-01

    Cronobacter spp. are emerging neonatal pathogens in humans, associated with outbreaks of meningitis and sepsis. To cause disease, they must survive in blood and invade the central nervous system by penetrating the blood-brain barrier. C. sakazakii BAA-894 possesses an ~131-kb plasmid (pESA3) that encodes an outer membrane protease (Cpa) that has significant identity to proteins that belong to the Pla subfamily of omptins. Members of this subfamily of proteins degrade a number of serum proteins, including circulating complement, providing protection from the complement-dependent serum killing. Moreover, proteins of the Pla subfamily can cause uncontrolled plasmin activity by converting plasminogen to plasmin and inactivating the plasmin inhibitor α2-antiplasmin (α2-AP). These reactions enhance the spread and invasion of bacteria in the host. In this study, we found that an isogenic cpa mutant showed reduced resistance to serum in comparison to its parent C. sakazakii BAA-894 strain. Overexpression of Cpa in C. sakazakii or Escherichia coli DH5α showed that Cpa proteolytically cleaved complement components C3, C3a, and C4b. Furthermore, a strain of C. sakazakii overexpressing Cpa caused a rapid activation of plasminogen and inactivation of α2-AP. These results strongly suggest that Cpa may be an important virulence factor involved in serum resistance, as well as in the spread and invasion of C. sakazakii.

  13. Functional Screening of the Cronobacter sakazakii BAA-894 Genome reveals a role for ProP (ESA_02131) in carnitine uptake.

    PubMed

    Feeney, Audrey; Sleator, Roy D

    2015-01-01

    Cronobacter sakazakii is a neonatal pathogen responsible for up to 80% of fatalities in infected infants. Low birth weight infants and neonates infected with C. sakazakii suffer necrotizing enterocolitis, bacteraemia and meningitis. The mode of transmission most often associated with infection is powdered infant formula (PIF) which, with an aw of ∼0.2, is too low to allow most microorganisms to persist. Survival of C. sakazakii in environments subject to extreme hyperosmotic stress has previously been attributed to the uptake of compatible solutes including proline and betaine. Herein, we report the construction and screening of a C. sakazakii genome bank and the identification of ProP (ESA_02131) as a carnitine uptake system.

  14. Cpa, the Outer Membrane Protease of Cronobacter sakazakii, Activates Plasminogen and Mediates Resistance to Serum Bactericidal Activity▿

    PubMed Central

    Franco, A. A.; Kothary, M. H.; Gopinath, G.; Jarvis, K. G.; Grim, C. J.; Hu, L.; Datta, A. R.; McCardell, B. A.; Tall, B. D.

    2011-01-01

    Cronobacter spp. are emerging neonatal pathogens in humans, associated with outbreaks of meningitis and sepsis. To cause disease, they must survive in blood and invade the central nervous system by penetrating the blood-brain barrier. C. sakazakii BAA-894 possesses an ∼131-kb plasmid (pESA3) that encodes an outer membrane protease (Cpa) that has significant identity to proteins that belong to the Pla subfamily of omptins. Members of this subfamily of proteins degrade a number of serum proteins, including circulating complement, providing protection from the complement-dependent serum killing. Moreover, proteins of the Pla subfamily can cause uncontrolled plasmin activity by converting plasminogen to plasmin and inactivating the plasmin inhibitor α2-antiplasmin (α2-AP). These reactions enhance the spread and invasion of bacteria in the host. In this study, we found that an isogenic cpa mutant showed reduced resistance to serum in comparison to its parent C. sakazakii BAA-894 strain. Overexpression of Cpa in C. sakazakii or Escherichia coli DH5α showed that Cpa proteolytically cleaved complement components C3, C3a, and C4b. Furthermore, a strain of C. sakazakii overexpressing Cpa caused a rapid activation of plasminogen and inactivation of α2-AP. These results strongly suggest that Cpa may be an important virulence factor involved in serum resistance, as well as in the spread and invasion of C. sakazakii. PMID:21245266

  15. Effect of polymyxin resistance (pmr) on biofilm formation of Cronobacter sakazakii.

    PubMed

    Bao, Xuerui; Jia, Xiangyin; Chen, Lequn; Peters, Brian M; Lin, Chii-Wann; Chen, Dingqiang; Li, Lin; Li, Bing; Li, Yanyan; Xu, Zhenbo; Shirtliff, Mark E

    2017-05-01

    Cronobacter sakazakii (C.sakazakii) has been identified as a wide-spread conditioned pathogen associated with series of serious illnesses, such as neonatal meningitis, enterocolitis, bacteremia or sepsis. As food safety is concerned, microbial biofilm has been considered to be a potential source of food contamination. The current study aims to investigate the ability of biofilm formation of two C. sakazakii strains (wild type BAA 894 and pmrA mutant). Crystal violet (CV), XTT (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino carbonyl)-2H-(tetrazolium hydroxide)] assays, and scanning electron microscopy (SEM) are performed on different time points during biofilm formation of C. sakazakii strains. Furthermore, RNA-seq strategy is utilized and the transcriptome data is analyzed to study the expression of genes related to biofilm formation along with whole genome sequencing. For biomass, in the first 24 h, pmrA mutant produced approximately 5 times than wildtype. However, the wild type exhibited more biomass than pmrA mutant during the post maturation stage (7-14 d). In addition, the wildtype showed higher viability than pmrA mutant during the whole biofilm formation. This study represents the first evidence on the biofilm formation of C. sakazakii pmrA mutant, which may further aid in the prevention and control for the food contamination caused by C. sakazakii. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Cronobacter (Enterobacter) sakazakii

    USDA-ARS?s Scientific Manuscript database

    Cronobacter sakazakii has been identified as an infrequently isolated opportunistic pathogen. Over 120 cases of C. sakazakii-related illness have been reported and most reported cases are life-threatening infections. Many of these outbreaks have been linked the consumption of C. sakazakii-contamina...

  17. Duplex Real-Time PCR Method for the Differentiation of Cronobacter sakazakii and Cronobacter malonaticus.

    PubMed

    Li, Xiaofang; Cui, Jinghua; Du, Xiaoli; Cui, Zhigang; Huang, Yibing; Kan, Biao

    2017-01-01

    Cronobacter sakazakii and Cronobacter malonaticus are the most common species of Cronobacter , so it is necessary to detect the two species as soon as possible in surveillance programs. We developed a real-time PCR method for identifying C. sakazakii and C. malonaticus from the genus Cronobacter . In this study, the two pairs of primers and probes were designed, targeting 16S rRNA and fusA, respectively. The specificity of the real-time PCR assay was validated with 112 strains of Cronobacter , including 56 C. sakazakii , 32 C. malonaticus , 16 Cronobacter dublinensis , 6 Cronobacter turicensis , and 2 Cronobacter muytjensii . The results showed that C. sakazakii and C. malonaticus were all correctly identified, consistent with the results of another method by analyzing the clustering of the fusA sequence. The detection limit for pure culture was 10 2 CFU/ml and 10 3 CFU/g for artificially contaminated rehydrated powdered infant formula. Therefore, the developed real-time PCR was a rapid, sensitive, and reliable method for the identification of C. sakazakii and C. malonaticus .

  18. Stress tolerant virulent strains of Cronobacter sakazakii from food.

    PubMed

    Fakruddin, Md; Rahaman, Mizanur; Ahmed, Monzur Morshed; Hoque, Md Mahfuzul

    2014-11-25

    Cronobacter sakazakii is considered as an emerging foodborne pathogen. The aim of this study was to isolate and characterize virulent strains of Cronobacter sakazakii from food samples of Bangladesh. Six (6) Cronobacter sakazakii was isolated and identified from 54 food samples on the basis of biochemical characteristics, sugar fermentation, SDS-PAGE of whole cell protein, plasmid profile and PCR of Cronobacter spp. specific genes (esak, gluA, zpx, ompA, ERIC, BOX-AIR) and sequencing. These strains were found to have moderately high antibiotic resistance against common antibiotics and some are ESBL producer. Most of the C. sakazakii isolates were capable of producing biofilm (strong biofilm producer), extracellular protease and siderophores, curli expression, haemolysin, haemagglutinin, mannose resistant haemagglutinin, had high cell surface hydrophobicity, significant resistance to human serum, can tolerate high concentration of salt, bile and DNase production. Most of them produced enterotoxins of different molecular weight. The isolates pose significant serological cross-reactivity with other gram negative pathogens such as serotypes of Salmonella spp., Shigella boydii, Shigella sonnei, Shigella flexneri and Vibrio cholerae. They had significant tolerance to high temperature, low pH, dryness and osmotic stress. Special attention should be given in ensuring hygiene in production and post-processing to prevent contamination of food with such stress-tolerant virulent Cronobacter sakazakii.

  19. Comparison of Chromogenic Selective Media for the Detection of Cronobacter spp. (Enterobacter sakazakii).

    PubMed

    Teramura, Hajime; Fukuda, Noriko; Okada, Yumiko; Ogihara, Hirokazu

    2018-01-01

     The four types of chromogenic selective media that are commercially available in Japan were compared for establishing a Japanese standard method for detecting Cronobacter spp. based on ISO/TS 22964:2006. When assessed using 9 standard Cronobacter spp. strains and 29 non-Cronobacter strains, Enterobacter sakazakii isolation agar, Chromocult TM Enterobacter sakazakii agar, CHROMagar TM E. sakazakii, and XM-sakazakii agar demonstrated excellent inclusivity and exclusivity. Using the ISO/TS 22964:2006 method, the recovered numbers of 38 Cronobacter spp. strains, including 29 C. sakazakii isolates obtained from each medium, were equivalent, indicating that there was no significant difference (p > 0.05) among the four types of chromogenic selective media. Thus, we demonstrated that these four chromogenic selective media are suitable alternatives when using the standard method for detecting Cronobacter spp. in Japan, based on the ISO/TS 22964:2006.

  20. [Isolation and identification of Cronobacter (Enterobacter sakazakii) strains from food].

    PubMed

    Dong, Xiaohui; Li, Chengsi; Wu, Qingping; Zhang, Jumei; Mo, Shuping; Guo, Weipeng; Yang, Xiaojuan; Xu, Xiaoke

    2013-05-04

    This study aimed to detect and quantify Cronobacter in 300 powdered milk samples and 50 non-powdered milk samples. Totally, 24 Cronobacter (formerly Enterobacter sakazakii) strains isolated from powdered milk and other foods were identified and confirmed. Cronobacter strains were detected quantitatively using most probable number (MPN) method and molecular detection method. We identified 24 Cronobacter strains using biochemical patterns, including indole production and dulcitol, malonate, melezitose, turanose, and myo-Inositol utilization. Of the 24 strains, their 16S rRNA genes were sequenced, and constructed phylogenetic tree by N-J (Neighbour-Joining) with the 16S rRNA gene sequences of 17 identified Cronobacter strains and 10 non-Cronobacter strains. Quantitative detection showed that Cronobacter strains were detected in 23 out of 350 samples yielding 6.6% detection rate. Twenty-four Cronobacter strains were isolated from 23 samples and the Cronobacter was more than 100 MPN/100g in 4 samples out of 23 samples. The 24 Cronobacter spp. isolates strains were identified and confirmed, including 19 Cronobacter sakazakii strains, 2 C. malonaticus strains, 2 C. dubliensis subsp. lactaridi strains, and 1 C. muytjensii strain. The combination of molecular detection method and most probable number (MPN) method could be suitable for the detection of Cronobacter in powdered milk, with low rate of contamination and high demand of quantitative detection. 24 isolated strains were confirmed and identified by biochemical patterns and molecular technology, and C. sakazakii could be the dominant species. The problem of Cronobacter in powdered milk should be a hidden danger to nurseling, and should catch the government and consumer's attention.

  1. A Negative Regulator of Cellulose Biosynthesis, bcsR, Affects Biofilm Formation, and Adhesion/Invasion Ability of Cronobacter sakazakii.

    PubMed

    Gao, Jian-Xin; Li, Ping; Du, Xin-Jun; Han, Zhong-Hui; Xue, Rui; Liang, Bin; Wang, Shuo

    2017-01-01

    Cronobacter sakazakii is an important foodborne pathogen that causes neonatal meningitis and sepsis, with high mortality in neonates. However, very little information is available regarding the pathogenesis of C. sakazakii at the genetic level. In our previous study, a cellulose biosynthesis-related gene ( bcsR ) was shown to be involved in C. sakazakii adhesion/invasion into epithelial cells. In this study, the detailed functions of this gene were investigated using a gene knockout technique. A bcsR knockout mutant (Δ bcsR ) of C. sakazakii ATCC BAA-894 showed decreased adhesion/invasion (3.9-fold) in human epithelial cell line HCT-8. Biofilm formation by the mutant was reduced to 50% of that exhibited by the wild-type (WT) strain. Raman spectrometry was used to detect variations in biofilm components caused by bcsR knockout, and certain components, including carotenoids, fatty acids, and amides, were significantly reduced. However, another biofilm component, cellulose, was increased in Δ bcsR , suggesting that bcsR negatively affects cellulose biosynthesis. This result was also verified via RT-PCR, which demonstrated up-regulation of five crucial cellulose synthesis genes ( bcsA, B, C, E, Q ) in Δ bcsR . Furthermore, the expression of other virulence or biofilm-related genes, including flagellar assembly genes ( fliA, C, D ) and toxicity-related genes ( ompA, ompX, hfq ), was studied. The expression of fliC and ompA in the Δ bcsR mutant was found to be remarkably reduced compared with that in the wild-type and the others were also affected excepted ompX . In summary, bcsR is a negative regulator of cellulose biosynthesis but positively regulates biofilm formation and the adhesion/invasion ability of C. sakazakii .

  2. Carriage of Cronobacter sakazakii in the very preterm infant gut.

    PubMed

    Chandrasekaran, Sukantha; Burnham, Carey-Ann D; Warner, Barbara B; Tarr, Phillip I; Wylie, Todd N

    2018-01-31

    Cronobacter sakazakii causes severe neonatal infections, but we know little about gut carriage of this pathogen in very low birthweight infants. We sequenced 16S rRNA genes from 2,304 stools from 121 children at St. Louis Children's Hospital whose birthweight was ≤1,500 grams, attempted to isolate C. sakazakii from 157 of these stools, genome sequenced the recovered isolates, and sought correlations between indices of Cronobacter excretion, host characteristics and unit formula use. Of these 2,304 stools, 1,271 (55.2%) contained Cronobacter rRNA gene sequences. The median (interquartile range) per-subject percent of specimens with at least one Cronobacter sequence and the median per-subject read density were 57.1 (25.5-87.3) and 0.07 (0.01-0.67), respectively. There was no variation according to commercially prepared liquid versus powdered formula use in the NICU, or the day-of-life that specimens were produced. However, the proportion of specimens containing >4.0% of reads mapping to Cronobacter fell from 4.3% to 0.9% after powdered infant formula was discontinued (P<0.0001). We isolated sequence type (ST) 4 C. sakazakii from multiple specimens from two subjects; one also harbored ST233. The sequenced ST4 isolates from the two subjects had >99.9% sequence identity in the ~93% of best-match reference genome that they contained, and shared multiple virulence loci. Very low birthweight infants excrete putatively pathogenic Cronobacter. High-density Cronobacter sequence samples were more common during the use of powdered infant formula. Better understanding of the ecology of Cronobacter in infant guts will inform future prevention and control strategies. © The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  3. Characterization of outer membrane vesicles from a neonatal meningitic strain of Cronobacter sakazakii.

    PubMed

    Alzahrani, Hayat; Winter, Jody; Boocock, David; De Girolamo, Luigi; Forsythe, Stephen J

    2015-06-01

    Cronobacter sakazakii is associated with severe and often fatal cases of infant meningitis and necrotizing enterocolitis. The form of meningitis differs from that due to Neisseria meningitidis and Streptococcus spp., in that it is highly invasive and destructive towards human brain cells. However, there is relatively little understanding of the cytopathogenic interaction of C. sakazakii with host cells which results in stimulation of an inflammatory immune response. The production of Cronobacter outer membrane vesicles (OMV) and their potential pathogenic functions have not yet been elucidated. This study is the first to show that C. sakazakii produce OMV, which may play a role in the activation of cytopathogenic and host cell responses on human intestinal epithelial cells. Cronobacter sakazakii strain 767 was used which had been isolated from a fatal outbreak of neonatal meningitis and necrotizing enterocolitis. Cronobacter sakazakii OMV were internalized by Caco-2 cells, increased cell proliferation and stimulated the host's innate proinflammatory response without inducing overt toxicity. A total of 18 OMV-associated proteins were identified by mass spectrometry and their potential pathogenicity roles were evaluated. Collectively, these data indicate that C. sakazakii OMV could play a role in pathogenesis by delivering bacterial toxins into host epithelial cells, driving proliferative and proinflammatory responses. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. CRISPR-cas loci profiling of Cronobacter sakazakii pathovars.

    PubMed

    Ogrodzki, Pauline; Forsythe, Stephen James

    2016-12-01

    Cronobacter sakazakii sequence types 1, 4, 8 and 12 are associated with outbreaks of neonatal meningitis and necrotizing enterocolitis infections. However clonality results in strains which are indistinguishable using conventional methods. This study investigated the use of clustered regularly interspaced short palindromic repeats (CRISPR)-cas loci profiling for epidemiological investigations. Seventy whole genomes of C. sakazakii strains from four clonal complexes which were widely distributed temporally, geographically and origin of source were profiled. All strains encoded the same type I-E subtype CRISPR-cas system with a total of 12 different CRISPR spacer arrays. This study demonstrated the greater discriminatory power of CRISPR spacer array profiling compared with multilocus sequence typing, which will be of use in source attribution during Cronobacter outbreak investigations.

  5. Immunochromatographic Strip Assay for Detection of Cronobacter sakazakii in Pure Culture.

    PubMed

    Song, Xinjie; Shukla, Shruti; Lee, Gibaek; Kim, Myunghee

    2016-11-28

    Cronobacter sakazakii ( C. sakazakii ) is a foodborne pathogen, posing a high risk of disease to infants and immunocompromised individuals. In order to develop a quick, easy, and sensitive assay for detecting C. sakazakii , a rabbit anti- C. sakazakii immunoglobulin G (IgG) was developed using sonicated cell protein from C. sakazakii . The developed anti- C. sakazakii (IgG) was of good quality and purity, as well as species-specific. The developed rabbit anti- C. sakazakii IgG was attached to the surface of a sulforhodamine B-encapsulated liposome to form an immunoliposome. A test strip was then prepared by coating goat anti-rabbit IgG onto the control line and rabbit anti- C. sakazakii IgG onto the test line, respectively, of a plastic-backed nitrocellulose membrane. A purple color signal both on the test line and the control line indicated the presence of C. sakazakii in the sample, whereas purple color only on the control line indicated the absence of C. sakazakii in the sample. This immunochromatographic strip assay could produce results in 15 min with a limit of detection of 10 7 CFU/ml in C. sakazakii culture. The immunochromatographic strip assay also showed very good specificity without cross-reactivity with other tested Cronobacter species. Based on these results, the developed immunochromatographic strip assay is efficient for the detection of C. sakazakii and has high potential for on-site detection.

  6. Rapid inactivation of Cronobacter sakazakii on copper alloys following periods of desiccation stress.

    PubMed

    Elguindi, Jutta; Alwathnani, Hend A; Rensing, Christopher

    2012-04-01

    Cronobacter spp. have been identified as the causative agent in meningitis and necrotizing enterocolitis in premature infants which can be linked to the bacterium's desiccation resistance and persistence in powdered infant formula. In this study we examined the efficacy of copper cast alloys in contact killing of Cronobacter sakazakii following periods of desiccation stress. Cronobacter sakazakii cells suspended in Tryptic Soy Broth (TSB) were killed within 10 min while kept moist on 99.9% copper alloys and within 1 min of drying on 99.9% copper alloys. Survival times were unchanged after cells suspended in TSB were desiccated for 33 days. Cronobacter sakazakii cells suspended in infant formula were killed within 30 min under moist conditions and within 3 min of drying on 99.9% copper alloys. However, when desiccated in infant formula for 45 days, survival times decreased to 10 and 1 min in moist and dry conditions, respectively. In contrast, no decrease in viable cells was noted on stainless steel surfaces under the experimental conditions employed in this study. Cronobacter sakazakii was rapidly killed on copper alloys under all testing conditions of this study indicating that desiccation and copper ion resistance do not prolong survival. These results could have important implications for the utilization of copper in the production and storage of powdered infant formula.

  7. Thermal resistance of Cronobacter sakazakii isolated from baby food ingredients of dairy origin

    USDA-ARS?s Scientific Manuscript database

    Milk and whey powders are commonly used ingredients in powdered infant formula (PIF) and follow-up formula (FUF). In this study, Cronobacter sakazakii and Cronobacter dublinensis both of dairy origin and a reference strain, Cronobacter muytjensii ATCC 51329, were investigated for thermal inactivatio...

  8. Reassessment of Cronobacter spp. originally isolated as Enterobacter sakazakii from infant food.

    PubMed

    Akineden, Ömer; Heinrich, Vanessa; Gross, Madeleine; Usleber, Ewald

    2017-08-01

    Cronobacter spp. cause infant disease, several cases have been associated with powdered infant formulae (PIF). In the early 2000s, contamination of German PIF with these opportunistic pathogens was quite common. Before 2008, all isolates Cronobacter spp. had been classified as Enterobacter sakazakii, therefore little is known about species diversity within such isolates. Genetic, serologic, and biochemical traits of 80 Cronobacter isolates, originally obtained 2003-2006 within infant food surveys in Germany, were reassessed in this study. By sequencing of the fusA gene, all isolates were unambiguously assigned to two species, C. sakazakii (n = 73) and C. malonaticus (n = 7). PCR serotyping identified five C. sakazakii serotypes and two C. malonaticus serotypes, biochemical profiling yielded five biogroups. PFGE analysis also showed high heterogeneity in both species. Multilocus sequence typing of 26 selected isolates yielded 16 different sequence types (ST), including C. sakazakii ST 1 (n = 6) and the highly virulent ST 4 (n = 2). The results suggest that just two, but highly heterogeneous species were responsible for the Cronobacter contamination problem which challenged the German PIF industry in the beginning of this century. This fact may have influenced the success of efforts to identify and eliminate sources of contamination. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Inhibition of Cronobacter sakazakii Virulence Factors by Citral.

    PubMed

    Shi, Chao; Sun, Yi; Liu, Zhiyuan; Guo, Du; Sun, Huihui; Sun, Zheng; Chen, Shan; Zhang, Wenting; Wen, Qiwu; Peng, Xiaoli; Xia, Xiaodong

    2017-02-24

    Cronobacter sakazakii is a foodborne pathogen associated with fatal forms of necrotizing enterocolitis, meningitis and sepsis in neonates and infants. The aim of this study was to determine whether citral, a major component of lemongrass oil, could suppress putative virulence factors of C. sakazakii that contribute to infection. Sub-inhibitory concentrations of citral significantly decreased motility, quorum sensing, biofilm formation and endotoxin production. Citral substantially reduced the adhesion and invasion of C. sakazakii to Caco-2 cells and decreased bacterial survival and replication within the RAW 264.7 macrophage cells. Citral also repressed the expression of eighteen genes involved in the virulence. These findings suggest that citral has potential to be developed as an alternative or supplemental agent to mitigate the infections caused by C. sakazakii.

  10. Antibacterial activities of plant-derived compounds and essential oils toward Cronobacter sakazakii and Cronobacter malonaticus.

    PubMed

    Fraňková, Adéla; Marounek, Milan; Mozrová, Věra; Weber, Jaroslav; Klouček, Pavel; Lukešová, Daniela

    2014-10-01

    Cronobacter sakazakii and C. malonaticus are opportunistic pathogens that cause infections in children and immunocompromised adults. In the present study, the antibacterial activity of 19 plant-derived compounds, 5 essential oils, and an extract of propolis were assessed against C. sakazakii and C. malonaticus. The effects of most of these antimicrobials have not been reported previously. Both strains were susceptible to thymol, carvacrol, thymoquinone, p-cymene, linalool, camphor, citral, eugenol, and trans-cinnamaldehyde as well as cinnamon, lemongrass, oregano, clove, and laurel essential oils; their minimum inhibitory concentrations varied between 0.1 and 2.0 mg/mL. As an alternative treatment method, vapors of the volatiles were tested as an indirect treatment. Vapors of trans-cinnamaldehyde, eugenol, oregano, and cinnamon essential oils inhibited both tested strains, while vapors of linalool were only active against C. sakazakii. To our knowledge, this study is the first time that the inhibitory activity of the vapors of these compounds and essential oils has been reported against Cronobacter spp.

  11. Insights into virulence factors determining the pathogenicity of Cronobacter sakazakii.

    PubMed

    Singh, Niharika; Goel, Gunjan; Raghav, Mamta

    2015-01-01

    Cronobacter sakazakii is an opportunistic pathogen associated with outbreaks of life-threatening necrotizing enterocolitis, meningitis and sepsis in neonates and infants. The pathogen possesses an array of virulence factors which aid in tissue adhesion, invasion and host cell injury. Although the identification and validation of C. sakazakii virulence factors has been hindered by availability of suitable neonatal animal model, various studies has reported outer membrane protein A (ompA) as a potential virulence marker. Various other plasmid associated genes such as filamentous hemagglutinin (fhaBC), Cronobacter plasminogen activator (cpa) and genes responsible for iron acquisition (eitCBAD and iucABD/iutA) have been reported in different strains of C. sakazakii. Besides these proposed virulence factors, several biophysical growth factors such as formation of biofilms and resistance to various environmental stresses also contributes to the pathogenic potential of this pathogen. This review provides an update on virulence determinants associated with the pathogenesis of C. sakazakii. The potential reservoirs of the pathogen, mode of transmission and epidemiology are also discussed.

  12. Insights into virulence factors determining the pathogenicity of Cronobacter sakazakii

    PubMed Central

    Singh, Niharika; Goel, Gunjan; Raghav, Mamta

    2015-01-01

    Cronobacter sakazakii is an opportunistic pathogen associated with outbreaks of life-threatening necrotizing enterocolitis, meningitis and sepsis in neonates and infants. The pathogen possesses an array of virulence factors which aid in tissue adhesion, invasion and host cell injury. Although the identification and validation of C. sakazakii virulence factors has been hindered by availability of suitable neonatal animal model, various studies has reported outer membrane protein A (ompA) as a potential virulence marker. Various other plasmid associated genes such as filamentous hemagglutinin (fhaBC), Cronobacter plasminogen activator (cpa) and genes responsible for iron acquisition (eitCBAD and iucABD/iutA) have been reported in different strains of C. sakazakii. Besides these proposed virulence factors, several biophysical growth factors such as formation of biofilms and resistance to various environmental stresses also contributes to the pathogenic potential of this pathogen. This review provides an update on virulence determinants associated with the pathogenesis of C. sakazakii. The potential reservoirs of the pathogen, mode of transmission and epidemiology are also discussed. PMID:25950947

  13. Cronobacter sakazakii clinical isolates overcome host barriers and evade the immune response.

    PubMed

    Almajed, Faisal S; Forsythe, Stephen J

    2016-01-01

    Cronobacter sakazakii is the most frequently clinically isolated species of the Cronobacter genus. However the virulence factors of C. sakazakii including their ability to overcome host barriers remains poorly studied. In this study, ten clinical isolates of C. sakazakii were assessed for their ability to invade and translocate through human colonic carcinoma epithelial cells (Caco-2) and human brain microvascular endothelial cells (HBMEC). Their ability to avoid phagocytosis in human macrophages U937 and human brain microglial cells was investigated. Additionally, they were tested for serum sensitivity and the presence of the Cronobacter plasminogen activation gene (cpa) gene, which is reported to confer serum resistance. Our data showed that the clinical C. sakazakii strains invaded and translocated through Caco-2 and HBMEC cell lines and some strains showed significantly higher levels of invasion and translocation. Moreover, C. sakazakii was able to persist and even multiply in phagocytic macrophage and microglial cells. All strains, except one, were able to withstand human serum exposure, the single serum sensitive strain was also the only one which did not encode for the cpa gene. These results demonstrate that C. sakazakii clinical isolates are able to overcome host barriers and evade the host immune response indicating their capacity to cause diseases such as necrotizing enterocolitis (NEC) and meningitis. Our data showed for the first time the ability of C. sakazakii clinical isolates to survive and multiply within human microglial cells. Additionally, it was shown that C. sakazakii clinical strains have the capacity to translocate through the Caco-2 and HBMEC cell lines paracellularly. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Genomic dissection of the 1994 Cronobacter sakazakii outbreak in a French neonatal intensive care unit.

    PubMed

    Masood, Naqash; Moore, Karen; Farbos, Audrey; Paszkiewicz, Konrad; Dickins, Ben; McNally, Alan; Forsythe, Stephen

    2015-10-05

    Cronobacter sakazakii is a member of the genus Cronobacter that has frequently been isolated from powdered infant formula (PIF) and linked with rare but fatal neonatal infections such as meningitis and necrotising enterocolitis. The Cronobacter MLST scheme has reported over 400 sequence types and 42 clonal complexes; however C. sakazakii clonal complex 4 (CC4) has been linked strongly with neonatal infections, especially meningitis. There have been a number of reported Cronobacter outbreaks over the last three decades. The largest outbreak of C. sakazakii was in a neonatal intensive care unit (NICU) in France (1994) that lasted over 3 months and claimed the lives of three neonates. The present study used whole genome sequencing data of 26 isolates obtained from this outbreak to reveal their relatedness. This study is first of its kind to use whole genome sequencing data to analyse a Cronobacter outbreak. Whole genome sequencing data was generated for 26 C. sakazakii isolates on the Illumina MiSeq platform. The whole genome phylogeny was determined using Mugsy and RaxML. SNP calls were determined using SMALT and SAMtools, and filtered using VCFtools. The whole genome phylogeny suggested 3 distant clusters of C. sakazakii isolates were associated with the outbreak. SNP typing and phylogeny indicate the source of the C. sakazakii could have been from extrinsic contamination of reconstituted infant formula from the NICU environment and personnel. This pool of strains would have contributed to the prolonged duration of the outbreak, which was up to 3 months. Furthermore 3 neonates were co-infected with C. sakazakii from two different genotype clusters. The genomic investigation revealed the outbreak consisted of an heterogeneous population of C. sakazakii isolates. The source of the outbreak was not identified, but probably was due to environmental and personnel reservoirs resulting in extrinsic contamination of the neonatal feeds. It also indicated that C. sakazakii

  15. Inhibition of Cronobacter sakazakii Virulence Factors by Citral

    PubMed Central

    Shi, Chao; Sun, Yi; Liu, Zhiyuan; Guo, Du; Sun, Huihui; Sun, Zheng; Chen, Shan; Zhang, Wenting; Wen, Qiwu; Peng, Xiaoli; Xia, Xiaodong

    2017-01-01

    Cronobacter sakazakii is a foodborne pathogen associated with fatal forms of necrotizing enterocolitis, meningitis and sepsis in neonates and infants. The aim of this study was to determine whether citral, a major component of lemongrass oil, could suppress putative virulence factors of C. sakazakii that contribute to infection. Sub-inhibitory concentrations of citral significantly decreased motility, quorum sensing, biofilm formation and endotoxin production. Citral substantially reduced the adhesion and invasion of C. sakazakii to Caco-2 cells and decreased bacterial survival and replication within the RAW 264.7 macrophage cells. Citral also repressed the expression of eighteen genes involved in the virulence. These findings suggest that citral has potential to be developed as an alternative or supplemental agent to mitigate the infections caused by C. sakazakii. PMID:28233814

  16. Identification of potential virulence factors of Cronobacter sakazakii isolates by comparative proteomic analysis.

    PubMed

    Ye, Yingwang; Li, Hui; Ling, Na; Han, Yongjia; Wu, Qingping; Xu, Xiaoke; Jiao, Rui; Gao, Jina

    2016-01-18

    Cronobacter is a group of important foodborne pathogens associated with neonatal meningitis, septicemia, and necrotizing enterocolitis. Among Cronobacter species, Cronobacter sakazakii is the most common species in terms of isolation frequency. However, the molecular basis involved in virulence differences among C. sakazakii isolates is still unknown. In this study, based on the determination of virulence differences of C. sakazakii G362 (virulent isolate) and L3101 (attenuated isolate) through intraperitoneal injection, histopathologic analysis (small intestine, kidney, and liver) further confirmed virulence differences. Thereafter, the potential virulence factors were determined using two-dimensional electrophoresis (2-DE) coupled with MALDI/TOP/TOF mass spectrometry. Among a total of 36 protein spots showing differential expression (fold change>1.2), we identified 31 different proteins, of which the expression abundance of 22 was increased in G362. These up-regulated proteins in G362 mainly contained DNA starvation/stationary phase protection protein Dps, OmpA, LuxS, ATP-dependent Clp protease ClpC, and ABC transporter substrate-binding proteins, which might be involved in virulence of C. sakazakii. This is the first report to determine the potential virulence factors of C. sakazakii isolates at the proteomic levels. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Virulent and pathogenic features on the Cronobacter sakazakii polymyxin resistant pmr mutant strain s-3.

    PubMed

    Bao, Xuerui; Yang, Ling; Chen, Lequn; Li, Bing; Li, Lin; Li, Yanyan; Xu, Zhenbo

    2017-09-01

    Cronobacter sakazakii is a well-known opportunistic pathogen responsible for necrotizing enterocolitis, meningitis and septicaemia in the premature, immunocompromised infants and neonates. This pathogen possesses various virulence factors and regulatory systems, and pmrA/pmrB regulatory system has been identified in a variety of bacterial species. The current study aims to investigate role of pmrA gene in the pathogenicity and virulence characteristics of Cronobacter sakazakii using whole genome sequencing and RNA-seq. Results demonstrated that the absence of pmrA has the potential to affect Cronobacter sakazakii on its pathogenicity, virulence and resistance abilities by regulating expression of numerous related genes, including CusB, CusC, CusR and ESA_pESA3p05434. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. International Life Science Institute North America Cronobacter (Formerly Enterobacter sakazakii) isolate set.

    PubMed

    Ivy, Reid A; Farber, Jeffrey M; Pagotto, Franco; Wiedmann, Martin

    2013-01-01

    Foodborne pathogen isolate collections are important for the development of detection methods, for validation of intervention strategies, and to develop an understanding of pathogenesis and virulence. We have assembled a publicly available Cronobacter (formerly Enterobacter sakazakii) isolate set that consists of (i) 25 Cronobacter sakazakii isolates, (ii) two Cronobacter malonaticus isolates, (iii) one Cronobacter muytjensii isolate, which displays some atypical phenotypic characteristics, biochemical profiles, and colony color on selected differential media, and (iv) two nonclinical Enterobacter asburiae isolates, which show some phenotypic characteristics similar to those of Cronobacter spp. The set consists of human (n = 10), food (n = 11), and environmental (n = 9) isolates. Analysis of partial 16S rDNA sequence and seven-gene multilocus sequence typing data allowed for reliable identification of these isolates to species and identification of 14 isolates as sequence type 4, which had previously been shown to be the most common C. sakazakii sequence type associated with neonatal meningitis. Phenotypic characterization was carried out with API 20E and API 32E test strips and streaking on two selective chromogenic agars; isolates were also assessed for sorbitol fermentation and growth at 45°C. Although these strategies typically produced the same classification as sequence-based strategies, based on a panel of four biochemical tests, one C. sakazakii isolate yielded inconclusive data and one was classified as C. malonaticus. EcoRI automated ribotyping and pulsed-field gel electrophoresis (PFGE) with XbaI separated the set into 23 unique ribotypes and 30 unique PFGE types, respectively, indicating subtype diversity within the set. Subtype and source data for the collection are publicly available in the PathogenTracker database (www. pathogentracker. net), which allows for continuous updating of information on the set, including links to publications that include

  19. Cronobacter sakazakii in foods and factors affecting its survival, growth, and inactivation

    USDA-ARS?s Scientific Manuscript database

    Cronobacter sakazakii has been isolated from a wide range of environmental sources and from several foods of animal and plant origin. While infections caused by C. sakazakii have predominantly involved neonates and infants, its presence on or in foods other than powdered infant formula raises conce...

  20. Development of Bioluminescent Cronobacter sakazakii ATCC 29544 in a Mouse Model.

    PubMed

    Wang, Xiwen; Li, Zhiping; Dong, Xiaolin; Chi, Hang; Wang, Guannan; Li, Jiakuan; Sun, Rui; Chen, Man; Zhang, Xinying; Wang, Yuanyuan; Qu, Han; Sun, Yu; Xia, Zhiping; Li, Qianxue

    2015-05-01

    Cronobacter sakazakii is an emerging pathogen that causes severe and life-threatening conditions including meningitis, bacteremia, and necrotizing enterocolitis. An animal model study for extrapolation of C. sakazakii infection can provide a better understanding of pathogenesis. However, methods for real-time monitoring of the course of C. sakazakii infection in living animals have been lacking. We developed a bioluminescent C. sakazakii strain (ATCC 29544) that can be used for real-time monitoring of C. sakazakii infection in BALB/c mice. C. sakazakii ATCC 29544 mainly colonized brain, liver, spleen, kidney, and gastrointestinal tract, as indicated by bioluminescence imaging. This work provides a novel approach for studying the progression of C. sakazakii infection and evaluating therapeutics in a living mouse model.

  1. Cronobacter sakazakii Infection from Expressed Breast Milk, Australia

    PubMed Central

    McMullan, Rowena; Menon, Vidthiya; Jensen, Slade O.; van Hal, Sebastiaan J.; Davis, Rebecca

    2018-01-01

    Cronobacter sakazakii neonatal infections are often epidemiologically linked to the consumption of contaminated powdered infant formula. We describe a case resulting from consumption of contaminated expressed breast milk, as confirmed by whole-genome sequencing. This case highlights potential risks associated with storage and acquisition of expressed breast milk. PMID:29350166

  2. Immunoliposome-based immunomagnetic concentration and separation assay for rapid detection of Cronobacter sakazakii.

    PubMed

    Shukla, Shruti; Lee, Gibaek; Song, Xinjie; Park, Sunhyun; Kim, Myunghee

    2016-03-15

    This study aimed to develop an immunoliposome-based immunomagnetic concentration and separation assay for the rapid detection of Cronobacter sakazakii (C. sakazakii), an acute opportunistic foodborne pathogenic bacterium, in both pure culture and infant formula. To develop the assay, magnetic nanoparticles (diameter 30 nm) were coated with immunoglobulin G (IgG), specifically anti-C. sakazakii IgG, and applied for the sensitive and efficient detection of C. sakazakii using immunoliposomes. The binding efficiency of anti-C. sakazakii IgG to the magnetic nanoparticles was 86.23 ± 0.59%. The assay developed in this study detected as few as 3.3 × 10(3) CFUmL(-1) of C. sakazakii in pure culture within 2h 30 min; in comparison, an indirect non-competitive enzyme-linked immunosorbent assay was able to detect 6.2 × 10(5) CFUmL(-1) of C. sakazakii in pure culture after 17 h. The developed assay did not show any cross-reactivity with other Cronobacter spp. or pathogens belonging to other genera. In addition, the method was able to detect 10(3) CFUmL(-1) of C. sakazakii in infant formula without any pre-incubation. These results confirm that the immunoliposome-based immunomagnetic concentration and separation assay may facilitate highly sensitive, efficient, and rapid detection of C. sakazakii. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Multiplexed Lateral Flow Test for Detection and Differentiation of Cronobacter sakazakii Serotypes O1 and O2

    PubMed Central

    Scharinger, Eva J.; Dietrich, Richard; Wittwer, Tobias; Märtlbauer, Erwin; Schauer, Kristina

    2017-01-01

    The ubiquitous and opportunistic pathogen Cronobacter sakazakii is responsible for severe meningitis, sepsis, and necrotizing enterocolitis in neonates and infants associated with ingestion of contaminated powdered infant formula (PIF). The current ISO method for isolation and detection of Cronobacter spp. is laborious, time-consuming and expensive. In this study, a multiplexed lateral flow test strip was developed to rapidly detect and simultaneously serotype O1 and O2 C. sakazakii serotypes. The assay is based on two monoclonal antibodies (MAb) that specifically bind to the lipopolysaccharides (LPS) of these pathogens. The test strip provides results very quickly; C. sakazakii could be detected in pure culture within 15 min with a sensitivity of 107 CFU/ml. After non-selective enrichment for 18 h as low as one Cronobacter cell per g PIF could be detected. Moreover, the established lateral flow assay (LFA) offers excellent specificity showing no cross-reactivity with other C. sakazakii serotypes, Cronobacter species or Enterobacteriaceae tested. These characteristics, together with several advantages such as speed, simplicity in performance, low analysis cost, and no requirement of specialized skills or sophisticated equipment make the developed multiplexed LFA suitable for reliable detection and serotyping of C. sakazakii serotypes O1 and O2. PMID:28979257

  4. Multiplexed Lateral Flow Test for Detection and Differentiation of Cronobacter sakazakii Serotypes O1 and O2.

    PubMed

    Scharinger, Eva J; Dietrich, Richard; Wittwer, Tobias; Märtlbauer, Erwin; Schauer, Kristina

    2017-01-01

    The ubiquitous and opportunistic pathogen Cronobacter sakazakii is responsible for severe meningitis, sepsis, and necrotizing enterocolitis in neonates and infants associated with ingestion of contaminated powdered infant formula (PIF). The current ISO method for isolation and detection of Cronobacter spp. is laborious, time-consuming and expensive. In this study, a multiplexed lateral flow test strip was developed to rapidly detect and simultaneously serotype O1 and O2 C. sakazakii serotypes. The assay is based on two monoclonal antibodies (MAb) that specifically bind to the lipopolysaccharides (LPS) of these pathogens. The test strip provides results very quickly; C. sakazakii could be detected in pure culture within 15 min with a sensitivity of 10 7 CFU/ml. After non-selective enrichment for 18 h as low as one Cronobacter cell per g PIF could be detected. Moreover, the established lateral flow assay (LFA) offers excellent specificity showing no cross-reactivity with other C. sakazakii serotypes, Cronobacter species or Enterobacteriaceae tested. These characteristics, together with several advantages such as speed, simplicity in performance, low analysis cost, and no requirement of specialized skills or sophisticated equipment make the developed multiplexed LFA suitable for reliable detection and serotyping of C. sakazakii serotypes O1 and O2.

  5. Profiling of Virulence Determinants in Cronobacter sakazakii Isolates from Different Plant and Environmental Commodities.

    PubMed

    Singh, Niharika; Raghav, Mamta; Narula, Shifa; Tandon, Simran; Goel, Gunjan

    2017-05-01

    Cronobacter sakazakii is an emerging pathogen causing meningitis, sepsis and necrotizing enterocolitis in neonates and immune-compromised adults. The present study describes the profiling of different virulence factors associated with C. sakazakii isolates derived from plant-based materials and environmental samples (soil, water, and vacuum dust). All the isolates exhibited β-hemolysis and chitinase activity, and were able to utilize inositol. Among the nine virulence-associated genes, hly gene coding for hemolysin was detected in all the isolates followed by ompA (outer membrane protein); however, plasmid-borne genes were detected at a level of 60% for both cpa (cronobacter plasminogen activator) and eitA (Ferric ion transporter protein) gene, respectively. Furthermore, the isolate C. sakazakii N81 showed cytotoxicity for Caco-2 cells. The presence of the virulence determinants investigated in this study indicates the pathogenic potential of C. sakazakii with their plausible connection with clinical manifestations.

  6. Cronobacter sakazakii bacteremia in a heart transplant patient with polycystic kidney disease.

    PubMed

    Tamigniau, A; Vanhaecke, J; Saegeman, V

    2015-12-01

    Infections with Cronobacter sakazakii are mainly described among neonates and infants, with contaminated powdered infant formulas most often incriminated as the cause. We describe here a case of C. sakazakii bacteremia secondary to a suspected cyst infection in a heart-and-kidney transplant patient with polycystic kidney disease. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Analysis of the cellulose synthase operon genes, bcsA, bcsB, and bcsC in Cronobacter species: Prevalence among species and their roles in biofilm formation and cell-cell aggregation.

    PubMed

    Hu, Lan; Grim, Christopher J; Franco, Augusto A; Jarvis, Karen G; Sathyamoorthy, Vengopal; Kothary, Mahendra H; McCardell, Barbara A; Tall, Ben D

    2015-12-01

    Cronobacter species are emerging food-borne pathogens that cause severe sepsis, meningitis, and necrotizing entercolitis in neonates and infants. Bacterial pathogens such as Escherichia coli and Salmonella species produce extracellular cellulose which has been shown to be involved in rugosity, biofilm formation, and host colonization. In this study the distribution and prevalence of cellulose synthase operon genes (bcsABZC) were determined by polymerase chain reaction (PCR) analysis in 231 Cronobacter strains isolated from clinical, food, environmental, and unknown sources. Furthermore, bcsA and bcsB isogenic mutants were constructed in Cronobacter sakazakii BAA894 to determine their roles. In calcofluor binding assays bcsA and bcsB mutants did not produce cellulose, and their colonial morphotypes were different to that of the parent strain. Biofilm formation and bacterial cell-cell aggregation were significantly reduced in bcsA and bcsB mutants compared to the parental strain. bcsA or bcsAB PCR-negative strains of C. sakazakii did not bind calcofluor, and produced less biofilm and cell-cell aggregation compared to strains possessing bcsAB genes. These data indicated that Cronobacter bcsABZC were present in all clinical isolates and most of food and environmental isolates. bcsA and bcsB genes of Cronobacter were necessary to produce cellulose, and were involved in biofilm formation and cell-cell aggregation. Published by Elsevier Ltd.

  8. A Newly Isolated Bacteriophage, PBES 02, Infecting Cronobacter sakazakii.

    PubMed

    Lee, Hyung Ju; Kim, Wan Il; Kwon, Young Chan; Cha, Kyung Eun; Kim, Minjin; Myung, Heejoon

    2016-09-28

    A novel bacteriophage, PBES 02, infecting Cronobacter sakazakii was isolated and characterized. It has a spherical head of 90 nm in diameter and a tail of 130 nm in length, and belongs to Myoviridae as observed under a transmission electron microscope. The major virion protein appears to be 38 kilodaltons (kDa) in size. The latent period of PBES 02 is 30 min and the burst size is 250. Infectivity of the phage remained intact after exposure to temperatures ranging from 4°C to 55°C for 1 h. It was also stable after exposure to pHs ranging from 6 to 10 for 1 h. The phage effectively removed contaminating Cronobacter sakazakii from broth infant formula. PBES 02 has a double-stranded DNA genome of 149,732 bases. Its GC ratio is 50.7%. Sequence analysis revealed that PBES 02 has 299 open reading frames (ORFs) and 14 tRNA genes. Thirty-nine ORFs were annotated, including 24 related to replication and regulation functions, 10 related to structural proteins, and 5 related to DNA packaging. The genome of PBES 02 is closely related to that of two other C. sakazakii phages, CR3 and CR8. Comparison of DNA sequences of genes encoding the major capsid protein revealed a wide geographical distribution of related phages over Asia, Europe, and America.

  9. Use of novel species-specific PCR primers targeted to DNA gyrase subunit B (gyrB) gene for species identification of the Cronobacter sakazakii and Cronobacter dublinensis.

    PubMed

    Huang, Chien-Hsun; Chang, Mu-Tzu; Huang, Lina

    2013-02-01

    Cronobacter sakazakii and its phylogenetically closest species are considered to be an opportunistic pathogens associated with food-borne disease in neonates and infants. Neither phenotypic nor genotypic (16S ribosomal DNA sequence analysis) techniques can provide sufficient resolutions for accurately and rapidly identification of these species. The objective of this study was to develop species-specific PCR based on the gyrB gene sequence for direct species identification of the C. sakazakii and Cronobacter dublinensis within the C. sakazakii group. Two pair of species-specific primers were designed and used to specifically identify C. sakazakii and C. dublinensis, but none of the other C. sakazakii group strains. Our data indicate that the novel species-specific primers could be used to rapidly and accurately identify the species of C. sakazakii and C. dublinensis from C. sakazakii group by the PCR based assays. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Nonthermal Inactivation of Cronobacter sakazakii in Infant Formula Milk: A Review.

    PubMed

    Pina-Pérez, M C; Rodrigo, D; Martínez, A

    2016-07-26

    Up-to-date, nonthermal technologies and combinations of them, in accordance with the "hurdle technology" concept, are being applied by different research groups in response to calls by the International Food and Human Health Organizations (ESPGHAN, 2004; FAO/WHO, 2006, 2008) for alternatives to thermal control of Cronobacter sakazakii in reconstituted powdered infant formula milk. This review highlights (i) current knowledge on the application of nonthermal technologies to control C. sakazakii in infant formula milk and (ii) the importance of the application of nonthermal technologies for the control of C. sakazakii as part of the development of strategies in the context of improving food safety and quality of this product.

  11. Cronobacter sakazakii reduction by blueberry proanthocyanidins.

    PubMed

    Joshi, Snehal S; Howell, Amy B; D'Souza, Doris H

    2014-05-01

    Blueberry juice and blueberry polyphenols reportedly have antimicrobial properties against foodborne pathogens, without much currently known on their effects against Cronobacter sakazakii. This study evaluated the antimicrobial effects of blueberry proanthocyanidins (PAC) and commercial blueberry juice (BJ) against two strains of C. sakazakii, ATCC 29004 and 29544. BJ (pH 2.8), blueberry PAC (5 mg/ml) and controls (phosphate buffered saline (PBS), pH 7.2, and malic acid pH 3.0) were mixed with equal volumes of washed overnight cultures of C. sakazakii and incubated for 30 min, 1 h, 3 h and 6 h at 37°C. Reductions of ∼1 and 1.50 log CFU/ml were obtained for strains 29004 and 29544, respectively after 30 min with BJ or blueberry PAC. Both C. sakazakii strains 29004 and 29544 were reduced to undetectable levels from 8.25 ± 0.12 log CFU/ml and 8.48 ± 0.03 log CFU/ml, respectively with BJ (pH 2.8) or blueberry PAC after 1 h, while malic acid (pH 3.0) showed ∼1.3 log CFU/ml reduction for both strains. Scanning electron microscopy studies showed differences in cell membrane morphology with clumping and formation of blebs of the treated strains compared to untreated controls. These results warrant further in vivo studies with blueberry bioactives to determine potential for preventing and treating C. sakazakii infections. Copyright © 2013. Published by Elsevier Ltd.

  12. Tea polyphenols inactivate Cronobacter sakazakii isolated from powdered infant formula.

    PubMed

    Li, R; Fei, P; Man, C X; Lou, B B; Niu, J T; Feng, J; Sun, L H; Li, M Y; Jiang, Y J

    2016-02-01

    This study evaluated the antimicrobial activity of tea polyphenols (TP) against 4 Cronobacter sakazakii strains with different sequence types (ST) isolated from powdered infant formula (PIF). The results showed that in normal saline, 5mg/mL of TP (pH 3.44) could eliminate approximately 7.0 log cfu/mL of C. sakazakii within 1 h; in rehydrated PIF, after acidification with HCl (pH 3.55), TP showed a stronger antibacterial activity compared with the controls (malic acid, ascorbic acid, and citric acid). Further, some differences were obvious in tolerance to TP between C. sakazakii strains with different ST. The tolerance of C. sakazakii CE1 (ST4) to TP was found to be greater than that of the other 3 C. sakazakii strains (ST1, ST8, and ST64). The results of recovered test and transmission electron microscope analysis revealed that the action of TP against C. sakazakii was an irreversible bactericidal process caused by leakage of cytoplasm. Taken together, these results indicated that TP had an effective bactericidal effect against C. sakazakii, and provided a new idea for preventing and inactivating C. sakazakii in PIF. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  13. Comparative proteomic analysis of Cronobacter sakazakii isolates with different virulences.

    PubMed

    Du, Xin-jun; Han, Ran; Li, Ping; Wang, Shuo

    2015-10-14

    Cronobacter is a genus of widespread, opportunistic, foodborne pathogens that can result in serious illnesses in at-risk infants because of their immature immunity and high dependence on powdered formula, which is one of the foods most often contaminated by this pathogen. However, limited information is available regarding the pathogenesis and the specific virulence factors of this species. In this study, the virulences of 42 Cronobacter sakazakii isolates were analyzed by infecting neonatal SD rats. A comparison of the typing patterns of the isolates enabled groups with close relationships but that exhibited distinct pathogenesis to be identified. Among these groups, 2 strains belonging to the same group but showing distinct virulences were selected, and 2-DE was applied to identify differentially expressed proteins, focusing on virulence-related proteins. A total of 111 protein spots were identified using matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF-MS), and 89 were successfully identified. Further analysis suggested that at least 11 of these proteins may be involved in the pathogenesis of this pathogen. Real-time PCR was carried out to further confirm the differential expression pattern of the genes, and the results indicated that the mRNA expression levels were consistent with the protein expression levels. The virulence factors and pathogenesis of Cronobacter are largely unknown. In combination with animal toxicological experiments and subtyping results of C. sakazakii, comparative proteomics analysis was performed to comprehensively evaluate the differentially expressed proteins of two isolates that exhibited distinct virulence but were closely related. These procedures made it possible to identify the virulence-related of factors of Cronobacter. Among the 89 total identified proteins, at least 11 show virulence-related potential. This work provides comprehensive candidates for the further investigation of

  14. Antibiotic and Desiccation Resistance of Cronobacter sakazakii and C. malonaticus Isolates from Powdered Infant Formula and Processing Environments

    PubMed Central

    Fei, Peng; Jiang, Yujun; Feng, Jing; Forsythe, Stephen J.; Li, Ran; Zhou, Yanhong; Man, Chaoxin

    2017-01-01

    This study evaluated the antimicrobial and desiccation resistance of Cronobacter sakazakii and Cronobacter malonaticus isolates from powdered infant formula and processing environments. The antimicrobial susceptibility tests showed that the 70 Cronobacter strains, representing 19 sequence types, were susceptible to the most of the antibiotics except for amoxicillin-clavulanate, ampicillin, and cefazolin. Furthermore, the growth of six C. sakazakii and two C. malonaticus strains from different sequence types (STs) in hyperosmotic media was measured. The growth of the two C. sakazakii strains (CE1 and CE13) from the neonatal pathovars ST4 and ST8, were significantly higher (p < 0.05) than that of other strains. C. malonaticus strain CM35 (ST201) was the slowest grower in all strains, and most could not grow in more than 8% NaCl solution. Also the survival of these strains under desiccation conditions was followed for 1 year. The viable count of Cronobacter spp. under desiccation conditions was reduced on average by 3.02 log cycles during 1 year, with CE13 (ST8) being the most desiccation resistant strain. These results will improve our understanding of the persistence of the two closely related species C. sakazakii and C. malonaticus which are of concern for neonatal and adult health. PMID:28303125

  15. Genotyping and Source Tracking of Cronobacter sakazakii and C. malonaticus Isolates from Powdered Infant Formula and an Infant Formula Production Factory in China

    PubMed Central

    Fei, Peng; Man, Chaoxin; Lou, Binbin; Forsythe, Stephen J.; Chai, Yunlei; Li, Ran; Niu, Jieting

    2015-01-01

    Cronobacter spp. (formerly defined as Enterobacter sakazakii) are opportunistic bacterial pathogens of both infants and adults. In this study, we analyzed 70 Cronobacter isolates from powdered infant formula (PIF) and an infant formula production facility in China to determine possible contamination routes. The strains were profiled by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), PCR-based O-antigen serotyping, and ompA and rpoB sequence analyses. The isolates were primarily Cronobacter sakazakii (66/70) or Cronobacter malonaticus (4/70). The strains were divided into 38 pulsotypes (PTs) using PFGE and 19 sequence types (STs) by MLST. In contrast, rpoB and ompA sequence analyses divided the strains into 10 overlapping clusters each. PCR serotyping of the 66 C. sakazakii and 4 C. malonaticus strains resulted in the identification of four C. sakazakii serotypes (O1, O2, O4, and O7) and a single C. malonaticus serotype, O2. The dominant C. sakazakii sequence types from PIF and an infant formula production factory in China were C. sakazakii clonal complex 4 (CC4) (n = 19), ST1 (n = 14), and ST64 (n = 11). C. sakazakii CC4 is a clonal lineage strongly associated with neonatal meningitis. In the process of manufacturing PIF, the spray-drying, fluidized-bed-drying, and packing areas were the main areas with Cronobacter contamination. C. sakazakii strains with the same pulsotypes (PT3 and PT2) and sequence types (ST1 and ST64) were isolated both from processing equipment and from the PIF finished product. PMID:26048942

  16. Acid stress management by Cronobacter sakazakii.

    PubMed

    Alvarez-Ordóñez, Avelino; Cummins, Conor; Deasy, Thérèse; Clifford, Tanya; Begley, Máire; Hill, Colin

    2014-05-16

    Cronobacter sakazakii is a foodborne pathogenic microorganism associated with sporadic cases of neonatal meningitis, necrotising enterocolitis, septicaemia, bloody diarrhoea and brain abscesses acquired through the consumption of contaminated powdered infant formula (PIF). This study aimed to investigate the growth of C. sakazakii DPC6529, a particularly stress tolerant clinical isolate, in acidified laboratory media and PIF. The possibility of a stationary-phase acid tolerance response (ATR) was also investigated. C. sakazakii DPC6529 grew in LB broth acidified to pH4.2 with hydrochloric acid (HCl) and was capable of relatively fast growth in PIF acidified to pH5.0 with HCl, representing the stomach pH reported for newborns and infants. Moreover, bacterial growth in LB broth supplemented with 1% (w/v) glucose gave rise to a stationary-phase ATR which resulted in enhanced survival against a subsequent acid challenge at pH3.0. A transposon mutagenesis approach was used to shed light on some of the molecular mechanisms involved in the response C. sakazakii DPC6529 to normally lethal acid exposures. The data suggests that repairing damage in proteins and nucleic acids, posttranscriptional modification of tRNA molecules and maintenance of the integrity of the cellular envelope are key processes in the defence against acid stress. Clones carrying transposon insertions in genes encoding the envelope stress response regulators CpxR and OmpR were identified as acid-sensitive mutants. Further analyses of the ompR defective mutant and its complemented counterpart evidenced that OmpR is a key player in the response of C. sakazakii to acid stress, although it was not essential to mount an active stationary-phase ATR, at least under the tested conditions. The ability of C. sakazakii DPC6529 to grow in acid environments and to develop an adaptive stationary-phase ATR may allow for its survival or even proliferation within the infant gastrointestinal tract after consumption of

  17. Genotyping and Source Tracking of Cronobacter sakazakii and C. malonaticus Isolates from Powdered Infant Formula and an Infant Formula Production Factory in China.

    PubMed

    Fei, Peng; Man, Chaoxin; Lou, Binbin; Forsythe, Stephen J; Chai, Yunlei; Li, Ran; Niu, Jieting; Jiang, Yujun

    2015-08-15

    Cronobacter spp. (formerly defined as Enterobacter sakazakii) are opportunistic bacterial pathogens of both infants and adults. In this study, we analyzed 70 Cronobacter isolates from powdered infant formula (PIF) and an infant formula production facility in China to determine possible contamination routes. The strains were profiled by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), PCR-based O-antigen serotyping, and ompA and rpoB sequence analyses. The isolates were primarily Cronobacter sakazakii (66/70) or Cronobacter malonaticus (4/70). The strains were divided into 38 pulsotypes (PTs) using PFGE and 19 sequence types (STs) by MLST. In contrast, rpoB and ompA sequence analyses divided the strains into 10 overlapping clusters each. PCR serotyping of the 66 C. sakazakii and 4 C. malonaticus strains resulted in the identification of four C. sakazakii serotypes (O1, O2, O4, and O7) and a single C. malonaticus serotype, O2. The dominant C. sakazakii sequence types from PIF and an infant formula production factory in China were C. sakazakii clonal complex 4 (CC4) (n = 19), ST1 (n = 14), and ST64 (n = 11). C. sakazakii CC4 is a clonal lineage strongly associated with neonatal meningitis. In the process of manufacturing PIF, the spray-drying, fluidized-bed-drying, and packing areas were the main areas with Cronobacter contamination. C. sakazakii strains with the same pulsotypes (PT3 and PT2) and sequence types (ST1 and ST64) were isolated both from processing equipment and from the PIF finished product. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  18. The Glutaredoxin Gene, grxB, Affects Acid Tolerance, Surface Hydrophobicity, Auto-Aggregation, and Biofilm Formation in Cronobacter sakazakii.

    PubMed

    Ling, Na; Zhang, Jumei; Li, Chengsi; Zeng, Haiyan; He, Wenjing; Ye, Yingwang; Wu, Qingping

    2018-01-01

    Cronobacter species are foodborne pathogens that can cause neonatal meningitis, necrotizing enterocolitis, and sepsis; they have unusual abilities to survive in environmental stresses such as acid stress. However, the factors involved in acid stress responses and biofilm formation in Cronobacter species are poorly understood. In this study, we investigated the role of grxB on cellular morphology, acid tolerance, surface hydrophobicity, auto-aggregation (AAg), motility, and biofilm formation in Cronobacter sakazakii . The deletion of grxB decreased resistance to acid stresses, and notably led to weaker surface hydrophobicity, AAg, and biofilm formation under normal and acid stress conditions, compared with those of the wild type strain; however, motility was unaffected. Therefore, grxB appears to contribute to the survival of C. sakazakii in acid stresses and biofilm formation. This is the first report to provide valuable evidence for the role of grxB in acid stress responses and biofilm formation in C. sakazakii.

  19. Genetic Characterization of Cronobacter sakazakii Recovered from the Environmental Surveillance Samples During a Sporadic Case Investigation of Foodborne Illness.

    PubMed

    Sulaiman, Irshad M; Jacobs, Emily; Segars, Katharine; Simpson, Steven; Kerdahi, Khalil

    2016-08-01

    Cronobacter sakazakii is an opportunistic human-pathogenic bacterium known to cause acute meningitis and necrotizing enterocolitis in neonates and immunocompromised individuals. This human-pathogenic microorganism has been isolated from a variety of food and environmental samples, and has been also linked to foodborne outbreaks associated with powdered infant formula (PIF). The U.S. Food and Drug Administration have a policy of zero tolerance of these organisms in PIF. Thus, this agency utilizes the presence of these microorganisms as one of the criteria in implementing regulatory actions and assessing adulteration of food products of public health importance. In this study, we recovered two isolates of Cronobacter from the 91 environmental swab samples during an investigation of sporadic case of foodborne illness following conventional microbiological protocols. The isolated typical colonies were identified using VITEK2 and real-time PCR protocols. The recovered Cronobacter isolates were then characterized for species identification by sequencing the 16S rRNA locus. Further, multilocus sequence typing (MLST) was accomplished characterizing seven known C. sakazakii-specific MLST loci (atpD, fusA, glnS, gltB, gyrB, infB, and pps). Results of this study confirmed all of the recovered Cronobacter isolates from the environmental swab samples to be C. sakazakii. The MLST profile matched with the published profile of the complex 31 of C. sakazakii. Thus, rRNA and 7-loci MLST-based sequencing protocols are robust techniques for rapid detection and differentiation of Cronobacter species, and these molecular diagnostic tools can be used in implementing successful surveillance program and in the control and prevention of foodborne illness.

  20. Efficiency of bacteriophage therapy against Cronobacter sakazakii in Galleria mellonella (greater wax moth) larvae.

    PubMed

    Abbasifar, Reza; Kropinski, Andrew M; Sabour, Parviz M; Chambers, James R; MacKinnon, Joanne; Malig, Thomas; Griffiths, Mansel W

    2014-09-01

    Cronobacter sakazakii, an opportunistic pathogen found in milk-based powdered infant formulae, has been linked to meningitis in infants, with high fatality rates. A set of phages from various environments were purified and tested in vitro against strains of C. sakazakii. Based on host range and lytic activity, the T4-like phage vB_CsaM_GAP161, which belongs to the family Myoviridae, was selected for evaluation of its efficacy against C. sakazakii. Galleria mellonella larvae were used as a whole-animal model for pre-clinical testing of phage efficiency. Twenty-one Cronobacter strains were evaluated for lethality in G. mellonella larvae. Different strains of C. sakazakii caused 0 to 98% mortality. C. sakazakii 3253, with an LD50 dose of ~2.0×10(5) CFU/larva (24 h, 37 °C) was selected for this study. Larvae infected with a dose of 5×LD50 were treated with phage GAP161 (MOI=8) at various time intervals. The mortality rates were as high as 100% in the groups injected with bacteria only, compared to 16.6% in the group infected with bacteria and treated with phage. Phage GAP161 showed the best protective activity against C. sakazakii when the larvae were treated prior to or immediately after infection. The results obtained with heat-inactivated phage proved that the survival of the larvae is not due to host immune stimulation. These results suggest that phage GAP161 is potentially a useful control agent against C. sakazakii. In addition, G. mellonella may be a useful whole-animal model for pre-screening phages for efficacy and safety prior to clinical evaluation in mammalian models.

  1. Growth kinetics and model comparison of cronobacter sakazakii in reconstituted powdered infant formula

    USDA-ARS?s Scientific Manuscript database

    Cronobacter sakazakii is a life-threatening bacterium, primarily implicated in illnesses associated with the consumption of powdered infant formula (PIF). It can cause rare but invasive infections, leading to sepsis, meningitis, or necrotizing enterocolitis in infants fed with contaminated PIF. Th...

  2. Cronobacter, the emergent bacterial pathogen Enterobacter sakazakii comes of age; MLST and whole genome sequence analysis.

    PubMed

    Forsythe, Stephen J; Dickins, Benjamin; Jolley, Keith A

    2014-12-16

    Following the association of Cronobacter spp. to several publicized fatal outbreaks in neonatal intensive care units of meningitis and necrotising enterocolitis, the World Health Organization (WHO) in 2004 requested the establishment of a molecular typing scheme to enable the international control of the organism. This paper presents the application of Next Generation Sequencing (NGS) to Cronobacter which has led to the establishment of the Cronobacter PubMLST genome and sequence definition database (http://pubmlst.org/cronobacter/) containing over 1000 isolates with metadata along with the recognition of specific clonal lineages linked to neonatal meningitis and adult infections Whole genome sequencing and multilocus sequence typing (MLST) has supports the formal recognition of the genus Cronobacter composed of seven species to replace the former single species Enterobacter sakazakii. Applying the 7-loci MLST scheme to 1007 strains revealed 298 definable sequence types, yet only C. sakazakii clonal complex 4 (CC4) was principally associated with neonatal meningitis. This clonal lineage has been confirmed using ribosomal-MLST (51-loci) and whole genome-MLST (1865 loci) to analyse 107 whole genomes via the Cronobacter PubMLST database. This database has enabled the retrospective analysis of historic cases and outbreaks following re-identification of those strains. The Cronobacter PubMLST database offers a central, open access, reliable sequence-based repository for researchers. It has the capacity to create new analysis schemes 'on the fly', and to integrate metadata (source, geographic distribution, clinical presentation). It is also expandable and adaptable to changes in taxonomy, and able to support the development of reliable detection methods of use to industry and regulatory authorities. Therefore it meets the WHO (2004) request for the establishment of a typing scheme for this emergent bacterial pathogen. Whole genome sequencing has additionally shown a range

  3. Sub-Inhibitory Concentrations of Trans-Cinnamaldehyde Attenuate Virulence in Cronobacter sakazakii in Vitro

    PubMed Central

    Amalaradjou, Mary Anne Roshni; Kim, Kwang Sik; Venkitanarayanan, Kumar

    2014-01-01

    Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, necrotizing colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ≤ 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen. PMID:24837831

  4. Sub-inhibitory concentrations of trans-cinnamaldehyde attenuate virulence in Cronobacter sakazakii in vitro.

    PubMed

    Amalaradjou, Mary Anne Roshni; Kim, Kwang Sik; Venkitanarayanan, Kumar

    2014-05-15

    Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, necrotizing colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ≤ 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen.

  5. Inactivation of Cronobacter sakazakii in reconstituted infant formula by combination of thymoquinone and mild heat.

    PubMed

    Shi, C; Jia, Z; Chen, Y; Yang, M; Liu, X; Sun, Y; Zheng, Z; Zhang, X; Song, K; Cui, L; Baloch, A B; Xia, X

    2015-12-01

    The objective of this study was to determine the combined effect of thymoquinone (TQ) and mild heat on Cronobacter sakazakii in reconstituted infant formula. Reconstituted infant formula samples inoculated with a mixture of four C. sakazakii strains (approx. 6·5 log CFU ml(-1) ) were prepared with various concentrations of TQ (0, 5, 10, 20 and 30 mmol l(-1) ) and were heated to 45, 50 and 55°C for 0, 10, 20, 30, 60 and 120 min, and the surviving populations of C. sakazakii at each sampling time were enumerated. To elucidate the mode of action of TQ, membrane integrity and changes in cell morphology were examined by LIVE/DEAD(®) BacLight(™) bacterial viability kit and field emission scanning electron microscope respectively. TQ at 30 mmol l(-1) reduced the pathogen to undetectable level in between 60 and 120 min at 45°C, 60 min at 50°C and 10 min at 55°C respectively. Our results demonstrated that the combined treatments significantly reduced (P < 0·05) the population of C. sakazakii, compared to the control. Cronobacter sakazakii numbers were reduced much more rapidly with higher temperatures and increased concentrations of TQ. And combined treatment inactivated pathogen partly by causing cell membrane disruption. These findings suggested that TQ, together with mild heat, may have potential application in infant formula to control C. sakazakii before consumption and therefore is a possible way to prevent infections associated with C. sakazakii in infant formula. © 2015 The Society for Applied Microbiology.

  6. Thymoquinone Inhibits Virulence Related Traits of Cronobacter sakazakii ATCC 29544 and Has Anti-biofilm Formation Potential.

    PubMed

    Shi, Chao; Yan, Chunhong; Sui, Yue; Sun, Yi; Guo, Du; Chen, Yifei; Jin, Tong; Peng, Xiaoli; Ma, Linlin; Xia, Xiaodong

    2017-01-01

    The aim of this study was to determine whether thymoquinone, the principal active ingredient in the volatile oil of Nigella sativa seeds, could suppress certain virulence traits of Cronobacter sakazakii ATCC 29544 which contribute to infection. Sub-inhibitory concentrations of thymoquinone significantly decreased motility, quorum sensing, and endotoxin production of C. sakazakii ATCC 29544 and biofilm formation of C. sakazakii 7-17. Thymoquinone substantially reduced the adhesion and invasion of C. sakazakii ATCC 29544 to HT-29 cells and decreased the number of intracellular bacterial cells within the RAW 264.7 macrophage cells. Thymoquinone also repressed the transcription of sixteen genes involved in the virulence. These findings suggest that thymoquinone could attenuated virulence-related traits of C. sakazakii ATCC 29544, and its effects on other C. sakazakii strains and in vivo C. sakazakii infection need further investigation.

  7. Thymoquinone Inhibits Virulence Related Traits of Cronobacter sakazakii ATCC 29544 and Has Anti-biofilm Formation Potential

    PubMed Central

    Shi, Chao; Yan, Chunhong; Sui, Yue; Sun, Yi; Guo, Du; Chen, Yifei; Jin, Tong; Peng, Xiaoli; Ma, Linlin; Xia, Xiaodong

    2017-01-01

    The aim of this study was to determine whether thymoquinone, the principal active ingredient in the volatile oil of Nigella sativa seeds, could suppress certain virulence traits of Cronobacter sakazakii ATCC 29544 which contribute to infection. Sub-inhibitory concentrations of thymoquinone significantly decreased motility, quorum sensing, and endotoxin production of C. sakazakii ATCC 29544 and biofilm formation of C. sakazakii 7-17. Thymoquinone substantially reduced the adhesion and invasion of C. sakazakii ATCC 29544 to HT-29 cells and decreased the number of intracellular bacterial cells within the RAW 264.7 macrophage cells. Thymoquinone also repressed the transcription of sixteen genes involved in the virulence. These findings suggest that thymoquinone could attenuated virulence-related traits of C. sakazakii ATCC 29544, and its effects on other C. sakazakii strains and in vivo C. sakazakii infection need further investigation. PMID:29234307

  8. The potential of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for the identification of biogroups of Cronobacter sakazakii.

    PubMed

    Karamonová, Ludmila; Junková, Petra; Mihalová, Denisa; Javůrková, Barbora; Fukal, Ladislav; Rauch, Pavel; Blažková, Martina

    2013-02-15

    The bacterial genus Cronobacter was established quite recently, in 2008. Therefore, its systematic classification is still in progress as well as the risk assessment of Cronobacter strains. The possibility of rapid identification within the biogroup level has an essential epidemiological significance. We examined the potential of mass spectrometry to accomplish this task on species Cronobacter sakazakii comprising eight different biogroups. Members of all Cronobacter sakazakii biogroups were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) using intact cells. Analyses were performed on a Biflex IV MALDI-TOF mass spectrometer in the range of 2000 to 20 000 Da in linear mode with an accelerated voltage of 19 kV. Optimal conditions for a proper identification of biogroups, such as suitable cultivation media or growth time of bacteria, were investigated. The biomarker patterns characterizing each of the Cronobacter sakazakii biogroups were obtained. The established identification protocol was applied to ten previously non-identified strains and their biogroups were successfully determined. The presented work is the first report of successful and rapid bacterial biogroup taxonomy classification using MALDI-TOF-MS that could substitute demanding biochemical testing. Copyright © 2012 John Wiley & Sons, Ltd.

  9. Antimicrobial Activity and Possible Mechanism of Action of Citral against Cronobacter sakazakii.

    PubMed

    Shi, Chao; Song, Kaikuo; Zhang, Xiaorong; Sun, Yi; Sui, Yue; Chen, Yifei; Jia, Zhenyu; Sun, Huihui; Sun, Zheng; Xia, Xiaodong

    2016-01-01

    Citral is a flavor component that is commonly used in food, beverage and fragrance industries. Cronobacter sakazakii is a food-borne pathogen associated with severe illness and high mortality in neonates and infants. The objective of the present study was to evaluate antimicrobial effect of citral against C. sakazakii strains. The minimum inhibitory concentration (MIC) of citral against C. sakazakii was determined via agar dilution method, then Gompertz models were used to quantitate the effect of citral on microbial growth kinetics. Changes in intracellular pH (pHin), membrane potential, intracellular ATP concentration, and membrane integrity were measured to elucidate the possible antimicrobial mechanism. Cell morphology changes were also examined using a field emission scanning electron microscope. The MICs of citral against C. sakazakii strains ranged from 0.27 to 0.54 mg/mL, and citral resulted in a longer lag phase and lower growth rate of C. sakazakii compared to the control. Citral affected the cell membrane of C. sakazakii, as evidenced by decreased intracellular ATP concentration, reduced pHin, and cell membrane hyperpolarization. Scanning electron microscopy analysis further confirmed that C. sakazakii cell membranes were damaged by citral. These findings suggest that citral exhibits antimicrobial effect against C. sakazakii strains and could be potentially used to control C. sakazakii in foods. However, how it works in food systems where many other components may interfere with its efficacy should be tested in future research before its real application.

  10. Antimicrobial Activity and Possible Mechanism of Action of Citral against Cronobacter sakazakii

    PubMed Central

    Shi, Chao; Song, Kaikuo; Zhang, Xiaorong; Sun, Yi; Sui, Yue; Chen, Yifei; Jia, Zhenyu; Sun, Huihui; Sun, Zheng; Xia, Xiaodong

    2016-01-01

    Citral is a flavor component that is commonly used in food, beverage and fragrance industries. Cronobacter sakazakii is a food-borne pathogen associated with severe illness and high mortality in neonates and infants. The objective of the present study was to evaluate antimicrobial effect of citral against C. sakazakii strains. The minimum inhibitory concentration (MIC) of citral against C. sakazakii was determined via agar dilution method, then Gompertz models were used to quantitate the effect of citral on microbial growth kinetics. Changes in intracellular pH (pHin), membrane potential, intracellular ATP concentration, and membrane integrity were measured to elucidate the possible antimicrobial mechanism. Cell morphology changes were also examined using a field emission scanning electron microscope. The MICs of citral against C. sakazakii strains ranged from 0.27 to 0.54 mg/mL, and citral resulted in a longer lag phase and lower growth rate of C. sakazakii compared to the control. Citral affected the cell membrane of C. sakazakii, as evidenced by decreased intracellular ATP concentration, reduced pHin, and cell membrane hyperpolarization. Scanning electron microscopy analysis further confirmed that C. sakazakii cell membranes were damaged by citral. These findings suggest that citral exhibits antimicrobial effect against C. sakazakii strains and could be potentially used to control C. sakazakii in foods. However, how it works in food systems where many other components may interfere with its efficacy should be tested in future research before its real application. PMID:27415761

  11. Identification of genes involved in serum tolerance in the clinical strain Cronobacter sakazakii ES5.

    PubMed

    Schwizer, Sarah; Tasara, Taurai; Zurfluh, Katrin; Stephan, Roger; Lehner, Angelika

    2013-02-15

    Cronobacter spp. are opportunistic pathogens that can cause septicemia and infections of the central nervous system primarily in premature, low-birth weight and/or immune-compromised neonates. Serum resistance is a crucial virulence factor for the development of systemic infections, including bacteremia. It was the aim of the current study to identify genes involved in serum tolerance in a selected Cronobacter sakazakii strain of clinical origin. Screening of 2749 random transposon knock out mutants of a C. sakazakii ES 5 library for modified serum tolerance (compared to wild type) revealed 10 mutants showing significantly increased/reduced resistance to serum killing. Identification of the affected sites in mutants displaying reduced serum resistance revealed genes encoding for surface and membrane proteins as well as regulatory elements or chaperones. By this approach, the involvement of the yet undescribed Wzy_C superfamily domain containing coding region in serum tolerance was observed and experimentally confirmed. Additionally, knock out mutants with enhanced serum tolerance were observed. Examination of respective transposon insertion loci revealed regulatory (repressor) elements, coding regions for chaperones and efflux systems as well as the coding region for the protein YbaJ. Real time expression analysis experiments revealed, that knock out of the gene for this protein negatively affects the expression of the fimA gene, which is a key structural component of the formation of fimbriae. Fimbriae are structures of high immunogenic potential and it is likely that absence/truncation of the ybaJ gene resulted in a non-fimbriated phenotype accounting for the enhanced survival of this mutant in human serum. By using a transposon knock out approach we were able to identify genes involved in both increased and reduced serum tolerance in Cronobacter sakazakii ES5. This study reveals first insights in the complex nature of serum tolerance of Cronobacter spp.

  12. Examine the Correlation between Heat Shock Protein IbpA and Heat Tolerance in Cronobacter sakazakii.

    PubMed

    Zhao, Zhi Jing; Wang, Bin; Yuan, Jing; Liang, Hao Yu; Dong, Si Guo; Zeng, Ming

    2017-08-01

    We used a proteomic approach to identify IbpA in Cronobacter sakazakii (C. sakazaki), which is related to heat tolerance in this strain. The abundance of IbpA in C. sakazakii strains strongly increased after heat shock. C. sakazakii CMCC 45402 ibpA deletion mutants were successfully constructed. The C. sakazakii CMCC 45402 ΔibpA and wild-type strains could not be distinguished based on colony morphology on LB agar plates or biochemical assays. The growth of the C. sakazakii CMCC 45402 ΔibpA mutant in heat shock conditions was indistinguishable from that of the isogenic wild-type, but showed greater heat resistance than E. coli O157:H7 strain CMCC 44828. This study suggests that the absence of a single ibpA gene has no obvious effect on the phenotype or heat resistance of the strain C. sakazakii CMCC 45402. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  13. Efficacy of the thin agar layer method for the recovery of stressed Cronobacter spp. (Enterobacter sakazakii).

    PubMed

    Osaili, Tareq M; Al-Nabulsi, Anas A; Shaker, Reyad R; Al-Holy, Murad M; Al-Haddaq, Mohammed S; Olaimat, Amin N; Ayyash, Mutamed M; Al Ta'ani, Mahmoud K; Forsythe, Stephen J

    2010-10-01

    Cronobacter spp. (Enterobacter sakazakii) are emerging opportunistic pathogens for all age groups, and are of particular concern when it comes to infants. Prior to contaminating food, the organism may be exposed to a variety of stresses, leading to a generation of sublethally injured cells that may not be detected by selective media unless a protracted recovery period is included in the isolation procedure. This study evaluated the efficacy of the thin agar layer (TAL) method for the recovery of Cronobacter cells that had been exposed to various stress conditions. Five strains of C. sakazakii and C. muytjensii were exposed to starvation, heat, cold, acid, alkaline, chlorine, or ethanol, with or without further exposure to desiccation stress. The recovery of the stressed cells was determined on tryptone soy agar (TSA; nonselective control medium), violet red bile glucose agar (VRBGA; selective agar), Druggan-Forsythe-Iversen (DFI; selective agar), and TAL media (viz., VRBGA overlaid with TSA, and DFI overlaid with TSA). Regardless of stress type, there were no significant differences among the recoveries of stressed desiccated Cronobacter spp. cultures on TSA, DFI+TSA, and VRBGA+TSA, but there was significantly less recovery on VRBGA. The recovery of prestressed desiccated Cronobacter spp. on DFI+TSA was similar to that on TSA, whereas the recovery on VRBGA+TSA was lower. DFI+TSA performed better than VRBGA+TSA did in differentiating Cronobacter spp. within mixed bacterial cultures. The results of this study suggest the use of the TAL method DFI+TSA as an improved method for the direct recovery of stressed Cronobacter spp.

  14. Hfq plays important roles in virulence and stress adaptation in Cronobacter sakazakii ATCC 29544.

    PubMed

    Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Yoon, Hyunjin; Kang, Dong-Hyun; Ryu, Sangryeol

    2015-05-01

    Cronobacter spp. are opportunistic pathogens that cause neonatal meningitis and sepsis with high mortality in neonates. Despite the peril associated with Cronobacter infection, the mechanisms of pathogenesis are still being unraveled. Hfq, which is known as an RNA chaperone, participates in the interaction with bacterial small RNAs (sRNAs) to regulate posttranscriptionally the expression of various genes. Recent studies have demonstrated that Hfq contributes to the pathogenesis of numerous species of bacteria, and its roles are varied between bacterial species. Here, we tried to elucidate the role of Hfq in C. sakazakii virulence. In the absence of hfq, C. sakazakii was highly attenuated in dissemination in vivo, showed defects in invasion (3-fold) into animal cells and survival (10(3)-fold) within host cells, and exhibited low resistance to hydrogen peroxide (10(2)-fold). Remarkably, the loss of hfq led to hypermotility on soft agar, which is contrary to what has been observed in other pathogenic bacteria. The hyperflagellated bacteria were likely to be attributable to the increased transcription of genes associated with flagellar biosynthesis in a strain lacking hfq. Together, these data strongly suggest that hfq plays important roles in the virulence of C. sakazakii by participating in the regulation of multiple genes. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. hfq Plays Important Roles in Virulence and Stress Adaptation in Cronobacter sakazakii ATCC 29544

    PubMed Central

    Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Yoon, Hyunjin; Kang, Dong-Hyun

    2015-01-01

    Cronobacter spp. are opportunistic pathogens that cause neonatal meningitis and sepsis with high mortality in neonates. Despite the peril associated with Cronobacter infection, the mechanisms of pathogenesis are still being unraveled. Hfq, which is known as an RNA chaperone, participates in the interaction with bacterial small RNAs (sRNAs) to regulate posttranscriptionally the expression of various genes. Recent studies have demonstrated that Hfq contributes to the pathogenesis of numerous species of bacteria, and its roles are varied between bacterial species. Here, we tried to elucidate the role of Hfq in C. sakazakii virulence. In the absence of hfq, C. sakazakii was highly attenuated in dissemination in vivo, showed defects in invasion (3-fold) into animal cells and survival (103-fold) within host cells, and exhibited low resistance to hydrogen peroxide (102-fold). Remarkably, the loss of hfq led to hypermotility on soft agar, which is contrary to what has been observed in other pathogenic bacteria. The hyperflagellated bacteria were likely to be attributable to the increased transcription of genes associated with flagellar biosynthesis in a strain lacking hfq. Together, these data strongly suggest that hfq plays important roles in the virulence of C. sakazakii by participating in the regulation of multiple genes. PMID:25754196

  16. Simultaneous Rapid Detection and Serotyping of Cronobacter sakazakii Serotypes O1, O2, and O3 by Using Specific Monoclonal Antibodies

    PubMed Central

    Scharinger, Eva J.; Dietrich, Richard; Kleinsteuber, Ina; Märtlbauer, Erwin

    2016-01-01

    Cronobacter sakazakii is a foodborne pathogen associated with rare but often lethal infections in neonates. Powdered infant formula (PIF) represents the most frequent source of infection. Out of the identified serotypes (O1 to O7), O1, O2, and O3 are often isolated from clinical and PIF samples. Serotype-specific monoclonal antibodies (MAbs) suitable for application in enzyme immunoassays (EIAs) for the rapid detection of C. sakazakii have not yet been developed. In this study, we created specific MAbs with the ability to bind to C. sakazakii of serotypes O1, O2, and O3. Characterization by indirect EIAs, immunofluorescence, motility assays, and immunoblotting identified lipopolysaccharide (LPS) and exopolysaccharide (EPS) as the antigenic determinants of the MAbs. The established sandwich EIAs were highly sensitive and were able to detect between 2 × 103 and 9 × 106 CFU/ml. Inclusivity tests confirmed that 93% of serotype O1 strains, 100% of O2 strains, and 87% of O3 strains were detected at low cell counts. No cross-reactivity with >100 strains of Cronobacter spp. and other Enterobacteriaceae was observed, except for that with C. sakazakii serotype O3 and Cronobacter muytjensii serotype O1. Moreover, the sandwich EIAs detected C. sakazakii in PIF samples artificially contaminated with 1 to 10 bacterial cells per 10 g of sample after 15 h of preenrichment. The use of these serotype-specific MAbs not only allows the reliable detection of C. sakazakii strains but also enables simultaneous serotyping in a simple sandwich EIA method. PMID:26850303

  17. Inhibition of quorum-sensing-mediated biofilm formation in Cronobacter sakazakii strains.

    PubMed

    Singh, Niharika; Patil, Amrita; Prabhune, Asmita; Goel, Gunjan

    2016-09-01

    The present study investigated plant extracts for their anti-quorum-sensing (QS) potential to inhibit the biofilm formation in Cronobacter sakazakii strains. The bioassay based on loss of pigment production by Chromobacterium violaceum 026 and Agrobacterium tumefaciens NTL4(pZLR4) was used for initial screening of the extracts. Further, the effect of extracts on the inhibition of QS-mediated biofilm in C. sakazakii isolates was evaluated using standard crystal violet assay. The effect on biofilm texture was studied using SYTO9 staining and light and scanning electron microscopy. Among the tested extracts, Piper nigrum and Cinnamomum verum at 100 ppm resulted in 78 and 68 % reduction in the production of violacein as well as blue-green colour in both biosensor strains. A higher inhibitory activity (>50 %) on biofilm formation in C. sakazakii was observed for Pip. nigrum and Cin. verum, whereas the other extracts possessed moderate (25-50 %) and minimal (<25 %) inhibitory activities. Further, the fluorescent and scanning electron microscopic images indicated a major disruption in the architecture of biofilms of tested strains by Pip. nigrum. This study points to the possibility of using Pip. nigrum and Cin. verum as inhibitor of QS-mediated biofilm formation by C. sakazakii that could be further explored for novel bioactive molecules to limit the emerging infections of C. sakazakii.

  18. Antimicrobial Activity of Ferulic Acid Against Cronobacter sakazakii and Possible Mechanism of Action.

    PubMed

    Shi, Chao; Zhang, Xiaorong; Sun, Yi; Yang, Miaochun; Song, Kaikuo; Zheng, Zhiwei; Chen, Yifei; Liu, Xin; Jia, Zhenyu; Dong, Rui; Cui, Lu; Xia, Xiaodong

    2016-04-01

    Cronobacter sakazakii is an opportunistic pathogen transmitted by food that affects mainly newborns, infants, and immune-compromised adults. In this study, the antibacterial activity of ferulic acid was tested against C. sakazakii strains. Minimum inhibitory concentration of ferulic acid against C. sakazakii strains was determined using the agar dilution method. Changes in intracellular pH, membrane potential and intracellular ATP concentration were measured to elucidate the possible antibacterial mechanism. Moreover, SYTO 9 nucleic acid staining was used to assess the effect of ferulic acid on bacterial membrane integrity. Cell morphology changes were observed under a field emission scanning electron microscope. The minimum inhibitory concentrations of ferulic acid against C. sakazakii strains ranged from 2.5 to 5.0 mg/mL. Addition of ferulic acid exerted an immediate and sustained inhibition of C. sakazakii proliferation. Ferulic acid affected the membrane integrity of C. sakazakii, as evidenced by intracellular ATP concentration decrease. Moreover, reduction of intracellular pH and cell membrane hyperpolarization were detected in C. sakazakii after exposure to ferulic acid. Reduction of green fluorescence indicated the injury of cell membrane. Electronic microscopy confirmed that cell membrane of C. sakazakii was damaged by ferulic acid. Our results demonstrate that ferulic acid has moderate antimicrobial activity against C. sakazakii. It exerts its antimicrobial action partly through causing cell membrane dysfunction and changes in cellular morphology. Considering its antimicrobial properties, together with its well-known nutritional functions, ferulic acid has potential to be developed as a supplement in infant formula or other foods to control C. sakazakii.

  19. Inhibition of Cronobacter sakazakii by Lactobacillus acidophilus n.v. Er2 317/402.

    PubMed

    Charchoghlyan, Haykuhi; Kwon, Heejun; Hwang, Dong-Ju; Lee, Jong Suk; Lee, Junsoo; Kim, Myunghee

    2016-10-31

    Lactobacillus acidophilus n.v. Er2 317/402 strain Narine is known as a health beneficial functional probiotic culture and supplementary source of nutrition for newborns. In this study, in vitro antimicrobial activities of Narine-lyophilized (Narine-L), Narine-heat treated (Narine-HT), and Narine crude cell-free extract (Narine-CCFE) were evaluated against pathogen Cronobacter sakazakii ( C. sakazakii ) in agar as well as in a reconstituted powdered infant formula (RPIF) model. Inhibition zones of 30 mg Narine-L and Narine-HT were both 150 U, whereas inhibition zone of 30 mg Narine-CCFE was 200 U. Narine-L (1 g) and Narine-HT (1 g) were added to 10 mL of artificially contaminated RPIF, respectively, containing 100 μL of C. sakazakii (1.62×10 8 colony forming unit (CFU)/mL). After treatment with Narine-L and Narine-HT for 3 h and 6 h at 37℃, less than ≤107 CFU/mL of C. sakazakii was detected in RPIF. Without Narine-L and Narine-HT treatment, the population of C. sakazakii increased up to 5.36×10 9 CFU/mL after 6 h. Examination by transmission electron microscopy confirmed C. sakazakii cells were damaged by Narine-CCFE. Thus, employing Narine culture as a natural and safe bio-preservative may protect infants from C. sakazakii .

  20. Detection of Cronobacter spp. (formerly Enterobacter sakazakii) from medicinal plants and spices in Syria.

    PubMed

    Belal, Mouhammad; Al-Mariri, Ayman; Hallab, Lila; Hamad, Ibtesam

    2013-02-15

    Cronobacter spp. (formerly Enterobacter sakazakii) is an emerging food-borne pathogen that causes severe meningitis, sepsis, and necrotizing enterocolitis in neonates and infants. These infections have been reported from different parts of the world. The epidemiology and reservoir of Cronobacter spp. are still unknown, and most strains have been isolated from clinical specimens and from a variety of foods, including cheese, meat, milk, vegetables, grains, spices, and herbs. Our study aimed to detect and isolate Cronobacter spp. from different Syrian samples of spices, medicinal herbs and liquorices, depending on the pigment production and biochemical profile of isolates and PCR technique. This PCR method, which provides a powerful tool for rapid, specific, and sensitive detection of Cronobacter spp., is considered a reliable alternative to traditional bacteriological methods. This study revealed that the percentage of Cronobacter spp. was 94%, 52%, and 32% in liquorice, spices and medicinal herbs, respectively. In addition, it assured that the optimal enhancing growth temperature was 44°C, and optimal enhancing growth pH was 5.

  1. Cronobacter sakazakii: stress survival and virulence potential in an opportunistic foodborne pathogen.

    PubMed

    Feeney, Audrey; Kropp, Kai A; O'Connor, Roxana; Sleator, Roy D

    2014-01-01

    A characteristic feature of the opportunistic foodborne pathogen Cronobacter sakazakii is its ability to survive in extremely arid environments, such as powdered infant formula, making it a dangerous opportunistic pathogen of individuals of all age groups, especially infants and neonates. Herein, we provide a brief overview of the pathogen; clinical manifestations, environmental reservoirs and our current understanding of stress response mechanisms and virulence factors which allow it to cause disease.

  2. Simultaneous Rapid Detection and Serotyping of Cronobacter sakazakii Serotypes O1, O2, and O3 by Using Specific Monoclonal Antibodies.

    PubMed

    Scharinger, Eva J; Dietrich, Richard; Kleinsteuber, Ina; Märtlbauer, Erwin; Schauer, Kristina

    2016-04-01

    Cronobacter sakazakii is a foodborne pathogen associated with rare but often lethal infections in neonates. Powdered infant formula (PIF) represents the most frequent source of infection. Out of the identified serotypes (O1 to O7), O1, O2, and O3 are often isolated from clinical and PIF samples. Serotype-specific monoclonal antibodies (MAbs) suitable for application in enzyme immunoassays (EIAs) for the rapid detection of C. sakazakii have not yet been developed. In this study, we created specific MAbs with the ability to bind toC. sakazakii of serotypes O1, O2, and O3. Characterization by indirect EIAs, immunofluorescence, motility assays, and immunoblotting identified lipopolysaccharide (LPS) and exopolysaccharide (EPS) as the antigenic determinants of the MAbs. The established sandwich EIAs were highly sensitive and were able to detect between 2 × 10(3)and 9 × 10(6)CFU/ml. Inclusivity tests confirmed that 93% of serotype O1 strains, 100% of O2 strains, and 87% of O3 strains were detected at low cell counts. No cross-reactivity with >100 strains of Cronobacter spp. and other Enterobacter iaceae was observed, except for that with C. sakazakii serotype O3 and Cronobacter muytjensii serotype O1. Moreover, the sandwich EIAs detected C. sakazakii in PIF samples artificially contaminated with 1 to 10 bacterial cells per 10 g of sample after 15 h of preenrichment. The use of these serotype-specific MAbs not only allows the reliable detection of C. sakazakii strains but also enables simultaneous serotyping in a simple sandwich EIA method. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Biochemical and molecular characterization of Cronobacter spp. (formerly Enterobacter sakazakii) isolated from foods.

    PubMed

    Turcovský, Imrich; Kuniková, Kristína; Drahovská, Hana; Kaclíková, Eva

    2011-02-01

    The aim of this study was to identify and characterize Cronobacter spp. isolated from a range of foods. A total of 71 Cronobacter strains were isolated from 602 foods in our laboratory. The highest contamination was observed in foods of plant origin, e.g. spices, teas, chocolate, nuts, pastries and vegetables. On the basis of genus and species identification performed using genus-specific PCR, 16S rRNA sequencing and AFLP genotyping, most of the strains belonged to Cronobacter sakazakii. Biochemical profiling by the tests included in API 20E, complemented with relevant additional tests, classified the strains into 13 biogroups. AFLP genotyping facilitated discrimination of six main groups at the 70% similarity level and strain grouping correlated clearly with species identification. Our results indicate that molecular typing by AFLP may be applied as a useful tool not only for direct comparison of Cronobacter isolates, providing traceability, but also for the reliable species classification. Moreover, tracing of these bacteria in a wider variety of foods should be important to enhance the knowledge of their transmission.

  4. Cronobacter sakazakii: stress survival and virulence potential in an opportunistic foodborne pathogen

    PubMed Central

    Feeney, Audrey; Kropp, Kai A; O’Connor, Roxana; Sleator, Roy D

    2014-01-01

    A characteristic feature of the opportunistic foodborne pathogen Cronobacter sakazakii is its ability to survive in extremely arid environments, such as powdered infant formula, making it a dangerous opportunistic pathogen of individuals of all age groups, especially infants and neonates. Herein, we provide a brief overview of the pathogen; clinical manifestations, environmental reservoirs and our current understanding of stress response mechanisms and virulence factors which allow it to cause disease. PMID:25562731

  5. Growth Inhibition of Cronobacter sakazakii in Experimentally Contaminated Powdered Infant Formula by Kefir Supernatant.

    PubMed

    Kim, Dong-Hyeon; Chon, Jung-Whan; Kang, Il-Byeong; Kim, Hyunsook; Kim, Hong-Seok; Song, Kwang-Young; Seo, Kun-Ho

    2015-09-01

    Kefir is a type of fermented milk containing lactic and acetic acid bacteria and yeast. In this study, we evaluated the antimicrobial activity of kefir supernatant against Cronobacter sakazakii in powdered infant formula (PIF). In a spot-on-lawn test, the growth of 20 C. sakazakii strains, including 10 clinical and 10 food isolates, was completely inhibited in the presence of kefir supernatant. Significant differences in the diameters of inhibition zones were observed upon treatment with kefir compared with the results for Lactobacillus kefiri and Candida kefyr culture supernatants or solutions of lactic and acetic acid and ethyl alcohol in the agar well diffusion test (P < 0.05). The addition of 100 μl of kefir supernatant to 1 ml of nutrient broth completely inhibited the growth of C. sakazakii, as evaluated by spectrophotometry. The antimicrobial activity of kefir supernatant in experimentally contaminated PIF was also tested; we found no viable C. sakazakii cells remaining in PIF rehydrated with 30% kefir supernatant solution for 1 h, demonstrating that the antimicrobial activity of kefir supernatant against C. sakazakii could be applied in real food samples.

  6. Structural derivation of lipid A from Cronobacter sakazakii using tandem mass spectrometry.

    PubMed

    Li, Yanyan; Yoon, Sung Hwan; Wang, Xiaoyuan; Ernst, Robert K; Goodlett, David R

    2016-10-30

    Cronobacter sakazakii is a Gram-negative opportunistic pathogen that can cause necrotizing enterocolitis, bacteremia, and meningitis. Lipid A, the glycolipid membrane anchor of lipopolysaccharide (LPS), is a potential virulence factor for C. sakazakii. Given the potential importance of this molecule in infection and virulence, structural characterization of lipid A was carried out. The structural characterization of lipid A extracted from C. sakazakii was performed using electrospray ionization and collision-induced dissociation in a linear ion trap mass spectrometer. Specifically, for detailed structural characterization, hierarchical tandem mass spectrometry was performed on the dominant ions present in the precursor ion mass spectra. By comparing the C. sakazakii fragmentation pathways to those of the known structure of E. coli lipid A, a structure of C. sakazakii lipid A was derived. The precursor ion at m/z 1796 from C. sakazakii is produced from a lipid A molecule where the acyl chains between the 2'b (C14) and 3'b (C12) positions are reversed as compared to E. coli lipid A. Additionally, the precursor ion at m/z 1824 from C. sakazakii corresponds to an E. coli structure with the same acyl chain at the 2'b position (C14), but a longer acyl chain (C14) at the 3'b position versus m/z 1796. Two lipid A structures were derived for the C. sakazakii ions at m/z 1796 and 1824. They differed in composition at the 2'b and 3'b acyl chain substituents, which may be a result of differences in substrate specificity of the two lipid A acyl chain transferases: LpxL and LpxM. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Electrochemical coupled immunosensing platform based on graphene oxide/gold nanocomposite for sensitive detection of Cronobacter sakazakii in powdered infant formula.

    PubMed

    Shukla, Shruti; Haldorai, Yuvaraj; Bajpai, Vivek K; Rengaraj, Arunkumar; Hwang, Seung Kyu; Song, Xinjie; Kim, Myunghee; Huh, Yun Suk; Han, Young-Kyu

    2018-06-30

    A sensitive electrochemical immunosensing platform for the detection of Cronobacter sakazakii was developed using a graphene oxide/gold (GO/Au) composite. Transmission electron microscopy showed that the Au nanoparticles, with an average size of < 30 nm, were well dispersed on the GO surface. For the detection of C. sakazakii, a polyclonal anti-C. sakazakii antibody (IgG) was covalently immobilized to the Au nanoparticles on the surface of the GO/Au composite coated glassy carbon electrode (GCE). The electrochemical sensing performance of immunofunctionalized GCE was characterized by cyclic voltammetry and differential pulse voltammetry. Under optimized conditions, in pure culture there was a linear relationship between electrical signal and C. sakazakii levels over the range 2.0 × 10 2 -2.0 × 10 7 cfu/mL (R 2 = 0.999), with a detection limit of 2.0 × 10 1 cfu/mL. The total analytical time was 15 min per sample. The C. sakazakii electrochemical immunosensing assay was able to successfully detect 2.0 × 10 1 cfu/mL of C. sakazakii in artificially contaminated powdered infant formula without any enrichment or pre-enrichment steps. Furthermore, the recovery rates of the C. sakazakii electrochemical immunosensing assay following spiking of powdered infant formula with different concentrations of C. sakazakii (cfu/mL) were 82.58% at 2.0 × 10 1 cfu/mL, 84.86% at 2.0 × 10 2 cfu/mL, and 95.40% at 2.0 × 10 3 cfu/mL. The C. sakazakii electrochemical immunosensing assay had good selectivity, reproducibility, and reactivity compared with other Cronobacter spp. and/or pathogens belonging to other genera, indicating its significant potential in the clinical diagnosis of C. sakazakii. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Heat Tolerances of Salmonella, Cronobacter sakazakii, and Pediococcus acidilactici Inoculated into Galactooligosaccharide.

    PubMed

    Bang, Jihyun; Choi, Moonkak; Jeong, Haeseok; Lee, Sangseob; Kim, Yoonbin; Ryu, Jee-Hoon; Kim, Hoikyung

    2017-07-01

    Food-grade galactooligosaccharide (GOS) with low water activity (a w of ca. 0.7) is used as an ingredient in various foods. We evaluated heat tolerances of Salmonella, Cronobacter sakazakii, and Pediococcus acidilactici at temperatures (70 to 85°C) used during the saturation process of GOS by comparing decimal reduction time (D-values) and thermal resistance constants (z-values). To determine the D- and z-values, GOS containing Salmonella (5.1 to 5.8 log CFU/g) or C. sakazakii (5.3 to 5.9 log CFU/g) was heat treated at 70, 77.5, or 85°C for up to 40, 25, or 15 s, respectively, and GOS containing P. acidilactici (6.1 to 6.5 log CFU/g) was heat treated at 70, 77.5, or 85°C for up to 150, 75, or 40 s, respectively. The D-values were calculated using a linear model for heating time versus microbial population for each bacterium. When the D-values for Salmonella, C. sakazakii, and P. acidilactici in GOS were compared, the thermal resistance of all bacteria decreased as the temperature increased. Among the three bacteria, P. acidilactici had higher D-values than did Salmonella and C. sakazakii. The z-values of Salmonella, C. sakazakii, and P. acidilactici were 30.10, 33.18, and 13.04°C, respectively. Overall order of thermal resistance was P. acidilactici > Salmonella ≈ C. sakazakii. These results will be useful for selecting appropriate heat treatment conditions for the decontamination of pathogenic microorganisms during GOS manufacturing.

  9. Antimicrobial activity of syringic acid against Cronobacter sakazakii and its effect on cell membrane.

    PubMed

    Shi, Chao; Sun, Yi; Zheng, Zhiwei; Zhang, Xiaorong; Song, Kaikuo; Jia, Zhenyu; Chen, Yifei; Yang, Miaochun; Liu, Xin; Dong, Rui; Xia, Xiaodong

    2016-04-15

    Syringic acid (SA) has been reported to exhibit antibacterial ability against various microorganisms, but little work has been done on its effect on Cronobacter sakazakii. In this study, minimum inhibitory concentrations (MICs) of SA against various C. sakazakii strains were determined. Moreover, changes in intracellular ATP concentration, intracellular pH (pHin), membrane potential and membrane integrity were measured to evaluate the influence of SA on cell membrane. Finally, field emission scanning electron microscope (FESEM) was used to assess the morphological changes of bacterial cells caused by SA. It was shown that the MICs of SA against all tested C. sakazakii strains were 5mg/mL. SA retarded bacterial growth, and caused cell membrane dysfunction, which was evidenced by intracellular ATP concentration decrease, pHin reduction, cell membrane hyperpolarization and changes in cellular morphology. These findings indicated that SA has potential to be developed as a natural preservative to control C. sakazakii in foods associated with this pathogen and prevent related infections. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Mining for sensitive and reliable species-specific primers for PCR for detection of Cronobacter sakazakii by a bioinformatics approach.

    PubMed

    Qiming, Chen; Tingting, Tao; Xiaomei, Bie; Yingjian, Lu; Fengxia, Lu; Ligong, Zhai; Zhaoxin, Lu

    2015-08-01

    Although several studies have reported PCR assays for distinguishing Cronobacter sakazakii from other species in the genus, reports regarding assay sensitivity and specificity, as well as applications for food testing, are lacking. Hence, the objective of this study was to develop a sensitive and reliable PCR-based method for detection of C. sakazakii by screening for specific target genes. The genome sequence of C. sakazakii in the GenBank database was compared with that of other organisms using BLAST. Thirty-eight DNA fragments unique to C. sakazakii were identified, and primers targeting these sequences were designed. Finally, 3 primer sets (CS14, CS21, and CS38) were found to be specific for C. sakazakii by PCR verification. The detection limit of PCR assays using the 3 pairs of primers was 1.35 pg/μL, 135 fg/μL, and 135 fg/μL, respectively, for genomic DNA, and 5.5×10(5), 5.5×10(3), 5.5×10(3) cfu/mL, respectively, using pure cultures of the bacteria, compared with 13.5 pg/μLand 5.5×10(5) cfu/mLfor primer set SpeCronsaka, which has been previously described. Cronobacter sakazakii were detected in artificially contaminated powdered infant formula (PIF) by PCR using primer sets CS21 and CS38 after 8h of enrichment. The detection limit was 5.5×10(-1) cfu/10g of PIF. Thus, the PCR assay can be used for rapid and sensitive detection of C. sakazakii in PIF. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. Influence of sweet whey protein concentrate and its hydrolysates on host-pathogen interactions in the emerging foodborne pathogen Cronobacter sakazakii.

    PubMed

    McEvoy, K; Hayes, J; Kealey, C; Brady, D

    2016-09-01

    Antimicrobial resistance poses a significant global healthcare predicament. An attractive approach to the dilemma of drug-resistant bacteria is the development and use of agents that interfere with the ability of pathogens to adhere to human tissue. The influence of sweet whey protein concentrate (SWPC), and selected hydrolysates of this material, on host-pathogen interactions of Cronobacter sakazakii (ATCC 29544) was investigated. CaCo-2 cell line was selected as a suitable model for the human intestinal epithelium. Cronobacter sakazakiiATCC 29544 was identified as the strain with the highest adhesion efficiency. SWPC reduced its association by 80% (P < 0·01), invasion 35% (P < 0·01), and translocation >95% (P < 0·001). SWPC enzymatically modified with lipase, trypsin and pepsin had variable effects on these behaviours with the most significant effect exhibited with the lipase treatment. SWPC produced an almost total inhibition of translocation of C. sakazakii across a CaCo-2 cell monolayer. Lipase and pepsin treated SWPC also reduced translocation by 75% and 90% respectively. However, trypsin treatment nullified the effect SWPC had on translocation. The presence of viable bacterial cells and SWPC both increased expression of IL-8 following Cronobacter invasion into CaCo-2 cells. Factors governing adherence, invasion and translocation of Cronobacter spp. to human intestinal cells are multi-factorial and digested milk products exhibit varying effects dependant on their enzyme modification and protein lipid content. These findings contribute to our, as yet, incomplete understanding of Cronobacter pathogenesis, and suggest that SWPC in whole and enzymatically hydrolysed forms, may provide a cost-effective source of bioactive materials with inhibitory effects on bacterial virulence. © 2016 The Society for Applied Microbiology.

  12. Comparative proteomic analysis of Cronobacter sakazakii by iTRAQ provides insights into response to desiccation.

    PubMed

    Hu, Shuangfang; Yu, Yigang; Wu, Xinwei; Xia, Xingzhou; Xiao, Xinglong; Wu, Hui

    2017-10-01

    Cronobacter sakazakii is a foodborne pathogen throughout the world and survives extremely desiccation stress. However, the molecular basis involved in desiccation resistance of C. sakazakii is still unknown. In this study, the potential desiccation resistance factors of C. sakazakii ATCC 29544 were determined using iTRAQ-based quantitative proteomic analysis. A total of 2775 proteins were identified by iTRAQ, of which 233 showed a different protein expression between control group and desiccation stress group. Among these 233 proteins identified as desiccation resistance proteins, there were 146 proteins downregulated and 87 proteins upregulated. According to the comprehensive proteome coverage analysis, C. sakazakii increased its resistance to desiccation by reducing the gene involved with unnecessary survival functions such as those used for virulence, adhesion, invasion and flagella assembly, while increasing gene expression of genes used in withstanding osmotic stress such as those genes involved in trehalose and betaine uptake. However, the mechanism involved in amino acid metabolism in an osmotic stress response, including the producing of γ-aminobutyric acid in C. sakazakii is still uncertain. This is the first report to determine the potential desiccation resistant factors of C. sakazakii at the proteomic levels. Copyright © 2017. Published by Elsevier Ltd.

  13. Cronobacter sakazakii DNA Detection in Cerebrospinal Fluid of a Patient with Amyotrophic Lateral Sclerosis Mimic Syndrome

    PubMed Central

    Piombo, Marianna; Chiarello, Daniela; Corbetto, Marzia; Di Pino, Giovanni; Dicuonzo, Giordano; Angeletti, Silvia; Riva, Elisabetta; De Florio, Lucia; Capone, Fioravante; Di Lazzaro, Vincenzo

    2015-01-01

    A 45-year-old male noticed progressive weakness of the right lower limb with gait disturbance. Over the following months, motor deficits worsened, spreading to the right upper limb. Electromyography showed active denervation in the upper and lower limb muscles. A diagnosis of amyotrophic lateral sclerosis (ALS) was made. About 2 years after symptom onset, gradual improvement occurred. Cerebrospinal fluid analysis performed about 3 years after the beginning of symptoms identified Cronobacter sakazakii. Since no other possible causes were identified, we suggest that an almost completely reversible ALS-like syndrome had been triggered by Cronobacter infection in our immunocompetent patient. PMID:26955334

  14. Drying parameters greatly affect the destruction of Cronobacter sakazakii and Salmonella Typhimurium in standard buffer and milk.

    PubMed

    Lang, Emilie; Iaconelli, Cyril; Zoz, Fiona; Guyot, Stéphane; Alvarez-Martin, Pablo; Beney, Laurent; Perrier-Cornet, Jean-Marie; Gervais, Patrick

    2017-04-01

    Salmonella Typhimurium and Cronobacter sakazakii are two foodborne pathogens involved in neonatal infections from milk powder and infant formula. Their ability to survive in low-moisture food and during processing from the decontamination to the dried state is a major issue in food protection. In this work, we studied the effects of the drying process on Salmonella Typhimurium and Cronobacter sakazakii, with the aim of identifying the drying parameters that could promote greater inactivation of these two foodborne pathogens. These two bacteria were dried under different atmospheric relative humidities in milk and phosphate-buffered saline, and the delays in growth recovery and cultivability were followed. We found that water activity was related to microorganism resistance. C. sakazakii was more resistant to drying than was S. Typhimurium, and milk increased the cultivability and recovery of these two species. High drying rates and low final water activity levels (0.11-0.58) had a strong negative effect on the growth recovery and cultivability of these species. In conclusion, we suggest that effective use of drying processes may provide a complementary tool for food decontamination and food safety during the production of low-moisture foods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Inactivation of Nondesiccated and Desiccated Cronobacter sakazakii in Reconstituted Infant Formula by Combination of Citral and Mild Heat.

    PubMed

    Shi, Chao; Jia, Zhenyu; Sun, Yi; Chen, Yifei; Guo, Du; Liu, Zhiyuan; Wen, Qiwu; Guo, Xiao; Ma, Linlin; Yang, Baowei; Baloch, Allah Bux; Xia, Xiaodong

    2017-07-01

    The objective of this study was to evaluate the combined effect of citral plus mild heat on nondesiccated and desiccated Cronobacter sakazakii in reconstituted infant formula. Various concentrations of citral (0, 0.3, 0.6, and 0.9%) combined with various temperatures (25, 45, 50, and 55°C) were applied to nondesiccated and desiccated cocktails of three C. sakazakii strains (approximately 6.0 log CFU mL -1 ) in reconstituted infant formula, and the bacterial populations were assayed periodically. The combined treatments had marked antimicrobial effects on C. sakazakii compared with the control. Desiccated cells were more susceptible to citral than were nondesiccated cells in reconstituted infant formula. These findings suggest there is a potential application of citral in combination with mild heat to control C. sakazakii during preparation of reconstituted infant formula.

  16. Genomic characterization of malonate positive Cronobacter sakazakii serotype O:2, sequence type 64 strains, isolated from clinical, food, and environment samples.

    PubMed

    Gopinath, Gopal R; Chase, Hannah R; Gangiredla, Jayanthi; Eshwar, Athmanya; Jang, Hyein; Patel, Isha; Negrete, Flavia; Finkelstein, Samantha; Park, Eunbi; Chung, TaeJung; Yoo, YeonJoo; Woo, JungHa; Lee, YouYoung; Park, Jihyeon; Choi, Hyerim; Jeong, Seungeun; Jun, Soyoung; Kim, Mijeong; Lee, Chaeyoon; Jeong, HyeJin; Fanning, Séamus; Stephan, Roger; Iversen, Carol; Reich, Felix; Klein, Günter; Lehner, Angelika; Tall, Ben D

    2018-01-01

    Malonate utilization, an important differential trait, well recognized as being possessed by six of the seven Cronobacter species is thought to be largely absent in Cronobacter sakazakii (Csak). The current study provides experimental evidence that confirms the presence of a malonate utilization operon in 24 strains of sequence type (ST) 64, obtained from Europe, Middle East, China, and USA; it offers explanations regarding the genomic diversity and phylogenetic relatedness among these strains, and that of other C. sakazakii strains. In this study, the presence of a malonate utilization operon in these strains was initially identified by DNA microarray analysis (MA) out of a pool of 347 strains obtained from various surveillance studies involving clinical, spices, milk powder sources and powdered infant formula production facilities in Ireland and Germany, and dried dairy powder manufacturing facilities in the USA. All ST64 C. sakazakii strains tested could utilize malonate. Zebrafish embryo infection studies showed that C. sakazakii ST64 strains are as virulent as other Cronobacter species. Parallel whole genome sequencing (WGS) and MA showed that the strains phylogenetically grouped as a separate clade among the Csak species cluster. Additionally, these strains possessed the Csak O:2 serotype. The nine-gene, ~ 7.7 kbp malonate utilization operon was located in these strains between two conserved flanking genes, gyrB and katG. Plasmidotyping results showed that these strains possessed the virulence plasmid pESA3, but in contrast to the USA ST64 Csak strains, ST64 Csak strains isolated from sources in Europe and the Middle East, did not possess the type six secretion system effector vgrG gene. Until this investigation, the presence of malonate-positive Csak strains, which are associated with foods and clinical cases, was under appreciated. If this trait was used solely to identify Cronobacter strains, many strains would likely be misidentified. Parallel WGS and

  17. Presence of AmpC beta-lactamases, CSA-1, CSA-2, CMA-1, and CMA-2 conferring an unusual resistance phenotype in Cronobacter sakazakii and Cronobacter malonaticus.

    PubMed

    Müller, Andrea; Hächler, Herbert; Stephan, Roger; Lehner, Angelika

    2014-08-01

    Here we describe the presence of two very similar but unusual variants of AmpC cephalosporinase in each Cronobacter sakazakii and C. malonaticus isolates conferring resistance exclusively to first generation cephalosporins. During a survey on the antibiotic resistance patterns of C. sakazakii and C. malonaticus strains isolated from a milk powder production facility, originally two different phenotypes regarding the susceptibility/resistance for the two beta-lactam antibiotics ampicillin (amp) and cephalothin (ceph) were observed: (i) isolates being susceptible for both antibiotics (amp(S)/ceph(S)), and (ii) strains exhibiting susceptibility to ampicillin but resistance to cephalothin (amp(S)/ceph(R)). The latter phenotype (amp(S)/ceph(R)) was observed in the majority of the environmental strains from the facility. Analysis of whole genome sequences of C. sakazakii revealed a gene putatively coding for an AmpC beta-lactamase. Consequently, the ampC genes from both species and both phenotypes were subjected to a cloning approach. Surprisingly, when expressed in Escherichia coli, all transformants exhibited the amp(S)/ceph(R) phenotype regardless of (i) the phenotypic backgrounds or (ii) the AmpC amino acid sequences of the original strains from which the clones were derived. The novel AmpC beta-lactamases were designated CSA-1 and CSA-2 (from C. sakazakii) and CMA-1 and CMA-2 (from C. malonaticus). The observed variations in the minimum inhibitory concentration (MIC) levels for cephalothin (wt compared to transformants) suggest that this feature is a target of a yet unknown regulatory mechanism present in the natural Cronobacter background but absent in the neutral E. coli host.

  18. Plasmid-Encoded MCP Is Involved in Virulence, Motility, and Biofilm Formation of Cronobacter sakazakii ATCC 29544

    PubMed Central

    Choi, Younho; Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Kang, Dong-Hyun

    2014-01-01

    The aim of this study was to elucidate the function of the plasmid-borne mcp (methyl-accepting chemotaxis protein) gene, which plays pleiotropic roles in Cronobacter sakazakii ATCC 29544. By searching for virulence factors using a random transposon insertion mutant library, we identified and sequenced a new plasmid, pCSA2, in C. sakazakii ATCC 29544. An in silico analysis of pCSA2 revealed that it included six putative open reading frames, and one of them was mcp. The mcp mutant was defective for invasion into and adhesion to epithelial cells, and the virulence of the mcp mutant was attenuated in rat pups. In addition, we demonstrated that putative MCP regulates the motility of C. sakazakii, and the expression of the flagellar genes was enhanced in the absence of a functional mcp gene. Furthermore, a lack of the mcp gene also impaired the ability of C. sakazakii to form a biofilm. Our results demonstrate a regulatory role for MCP in diverse biological processes, including the virulence of C. sakazakii ATCC 29544. To the best of our knowledge, this study is the first to elucidate a potential function of a plasmid-encoded MCP homolog in the C. sakazakii sequence type 8 (ST8) lineage. PMID:25332122

  19. Plasmid-encoded MCP is involved in virulence, motility, and biofilm formation of Cronobacter sakazakii ATCC 29544.

    PubMed

    Choi, Younho; Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Kang, Dong-Hyun; Ryu, Sangryeol

    2015-01-01

    The aim of this study was to elucidate the function of the plasmid-borne mcp (methyl-accepting chemotaxis protein) gene, which plays pleiotropic roles in Cronobacter sakazakii ATCC 29544. By searching for virulence factors using a random transposon insertion mutant library, we identified and sequenced a new plasmid, pCSA2, in C. sakazakii ATCC 29544. An in silico analysis of pCSA2 revealed that it included six putative open reading frames, and one of them was mcp. The mcp mutant was defective for invasion into and adhesion to epithelial cells, and the virulence of the mcp mutant was attenuated in rat pups. In addition, we demonstrated that putative MCP regulates the motility of C. sakazakii, and the expression of the flagellar genes was enhanced in the absence of a functional mcp gene. Furthermore, a lack of the mcp gene also impaired the ability of C. sakazakii to form a biofilm. Our results demonstrate a regulatory role for MCP in diverse biological processes, including the virulence of C. sakazakii ATCC 29544. To the best of our knowledge, this study is the first to elucidate a potential function of a plasmid-encoded MCP homolog in the C. sakazakii sequence type 8 (ST8) lineage. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  20. Rapid detection of Cronobacter sakazakii by real-time PCR based on the cgcA gene and TaqMan probe with internal amplification control.

    PubMed

    Hu, Shuangfang; Yu, Yigang; Li, Rong; Wu, Xinwei; Xiao, Xinglong; Wu, Hui

    2016-03-01

    Cronobacter sakazakii is a severe virulent strain that is frequently detected in powdered infant formula (PIF). Therefore, it is necessary to develop a fast and specific detection method. The specificity of our newly developed quantitative real-time PCR (qRT-PCR) was validated with DNA from 46 strains. Among them, 12 C. sakazakii strains were correctly amplified, whereas no positive florescent signal was observed from 34 nontarget controls. The detection limit of C. sakazakii was about 110 CFU/mL in broth and 1100 CFU/g in PIF. After enrichment in buffered peptone water for 6 h, our developed qRT-PCR assay could reliably detect C. sakazakii when the inoculation level was as low as 2 CFU/25 g (0.08 CFU/g) in PIF. The growth of C. sakazakii could be inhibited by the presence of Lactobacillus pentosus and Bacillus cereus, which used a longer enrichment period before the isolation was accomplished. However, at 5 and 50 CFU/25 g inoculation levels of C. sakazakii in the presence of 4 × 10(6) CFU L. pentosus/25 g or of 2 × 10(4) CFU B. cereus/25 g, the qRT-PCR assay could detect the presence of Cronobacter even though these artificially spiked samples were negative in culture. Therefore, our results indicated that the qRT-PCR assay could detect samples containing inhibitors and could avoid false negatives by using an internal amplification control.

  1. Detection of Cronobacter sakazakii in powdered infant formula using an immunoliposome-based immunomagnetic concentration and separation assay

    PubMed Central

    Shukla, Shruti; Lee, Gibaek; Song, Xinjie; Park, Jung Hyun; Cho, Hyunjeong; Lee, Eun Ju; Kim, Myunghee

    2016-01-01

    This study aimed to optimize the applicability of an immunoliposome-based immunomagnetic concentration and separation assay to facilitate rapid detection of Cronobacter sakazakii in powdered infant formula (PIF). To determine the detection limit, specificity, and pre-enrichment incubation time (0, 4, 6, and 8 h), assay tests were performed with different cell numbers of C. sakazakii (2 × 100 and 2 × 101 CFU/ml) inoculated in 10 g of PIF. The assay was able to detect as few as 2 cells of C. sakazakii/10 g of PIF sample after 6 h of pre-enrichment incubation with an assay time of 2 h 30 min. The assay was assessed for cross-reactivity with other bacterial strains and exhibited strong specificity to C. sakazakii. Moreover, the assay method was applied to the detection of C. sakazakii in PIF without pre-enrichment steps, and the results were compared with INC-ELISA and RT-PCR. The developed method was able to detect C. sakazakii in spiked PIF without pre-enrichment, whereas INC-ELISA failed to detect C. sakazakii. In addition, when compared with the results obtained with RT-PCR, our developed assay required lesser detection time. The developed assay was also not susceptible to any effect of the food matrix or background contaminant microflora. PMID:27721500

  2. Whole-Genome Sequences of Cronobacter sakazakii Isolates Obtained from Foods of Plant Origin and Dried-Food Manufacturing Environments.

    PubMed

    Jang, Hyein; Addy, Nicole; Ewing, Laura; Jean-Gilles Beaubrun, Junia; Lee, YouYoung; Woo, JungHa; Negrete, Flavia; Finkelstein, Samantha; Tall, Ben D; Lehner, Angelika; Eshwar, Athmanya; Gopinath, Gopal R

    2018-04-12

    Here, we present draft genome sequences of 29 Cronobacter sakazakii isolates obtained from foods of plant origin and dried-food manufacturing facilities. Assemblies and annotations resulted in genome sizes ranging from 4.3 to 4.5 Mb and 3,977 to 4,256 gene-coding sequences with G+C contents of ∼57.0%.

  3. Whole-Genome Sequences of Cronobacter sakazakii Isolates Obtained from Foods of Plant Origin and Dried-Food Manufacturing Environments

    PubMed Central

    Addy, Nicole; Ewing, Laura; Jean-Gilles Beaubrun, Junia; Lee, YouYoung; Woo, JungHa; Negrete, Flavia; Finkelstein, Samantha; Tall, Ben D.; Lehner, Angelika; Eshwar, Athmanya; Gopinath, Gopal R.

    2018-01-01

    ABSTRACT Here, we present draft genome sequences of 29 Cronobacter sakazakii isolates obtained from foods of plant origin and dried-food manufacturing facilities. Assemblies and annotations resulted in genome sizes ranging from 4.3 to 4.5 Mb and 3,977 to 4,256 gene-coding sequences with G+C contents of ∼57.0%. PMID:29650569

  4. Short communication: Roles of outer membrane protein W (OmpW) on survival and biofilm formation of Cronobacter sakazakii under neomycin sulfate stress.

    PubMed

    Ye, Yingwang; Ling, Na; Gao, Jina; Zhang, Maofeng; Zhang, Xiyan; Tong, Liaowang; Ou, Dexin; Wang, Yaping; Zhang, Jumei; Wu, Qingping

    2018-04-01

    Cronobacter sakazakii is associated with severe infections including sepsis, neonatal meningitis, and necrotizing enterocolitis. Antibiotic resistance in Cronobacter species has been documented in recent years, but the genes involved in resistance in Cronobacter strains are poorly understood. In this study, we determined the role of outer membrane protein W (OmpW) on survival rates, morphologic changes, and biofilm formation between wild type (WT) and an OmpW mutant strain (ΔOmpW) under neomycin sulfate stress. Results indicated that the survival rates of ΔOmpW were significantly reduced after half minimum inhibitory concentration (½ MIC) treatment compared with the WT strain. Filamentation of C. sakazakii cells was observed after ½ MIC treatment in WT and ΔOmpW, and morphologic injury, including cell disruption and leakage of cells, was more predominant in ΔOmpW. Under ½ MIC stress, the biofilms of WT and ΔOmpW were significantly decreased, but decreasing rates of biofilm formation in mutant strain were more predominant compared with WT strain. This is the first report to determine the role of OmpW on survival, morphological changes, and biofilm formation in C. sakazakii under neomycin sulfate stress. The findings indicated that OmpW contributed to survival and reduction of morphological injury under neomycin sulfate stress. In addition, enhancing biofilm formation in ΔOmpW may be an alternative advantage for adaptation to neomycin sulfate stress. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  5. Capsular profiling of the Cronobacter genus and the association of specific Cronobacter sakazakii and C. malonaticus capsule types with neonatal meningitis and necrotizing enterocolitis.

    PubMed

    Ogrodzki, P; Forsythe, S

    2015-10-08

    Cronobacter sakazakii and C. malonaticus can cause serious diseases especially in infants where they are associated with rare but fatal neonatal infections such as meningitis and necrotising enterocolitis. This study used 104 whole genome sequenced strains, covering all seven species in the genus, to analyse capsule associated clusters of genes involved in the biosynthesis of the O-antigen, colanic acid, bacterial cellulose, enterobacterial common antigen (ECA), and a previously uncharacterised K-antigen. Phylogeny of the gnd and galF genes flanking the O-antigen region enabled the defining of 38 subgroups which are potential serotypes. Two variants of the colanic acid synthesis gene cluster (CA1 and CA2) were found which differed with the absence of galE in CA2. Cellulose (bcs genes) were present in all species, but were absent in C. sakazakii sequence type (ST) 13 and clonal complex (CC) 100 strains. The ECA locus was found in all strains. The K-antigen capsular polysaccharide Region 1 (kpsEDCS) and Region 3 (kpsMT) genes were found in all Cronobacter strains. The highly variable Region 2 genes were assigned to 2 homology groups (K1 and K2). C. sakazakii and C. malonaticus isolates with capsular type [K2:CA2:Cell(+)] were associated with neonatal meningitis and necrotizing enterocolitis. Other capsular types were less associated with clinical infections. This study proposes a new capsular typing scheme which identifies a possible important virulence trait associated with severe neonatal infections. The various capsular polysaccharide structures warrant further investigation as they could be relevant to macrophage survival, desiccation resistance, environmental survival, and biofilm formation in the hospital environment, including neonatal enteral feeding tubes.

  6. Structural studies of O-polysaccharide isolated from Cronobacter sakazakii Sequence Type 12 from a case of neonatal necrotizing enterocolitis.

    PubMed

    Marszewska, Kinga; Czerwicka, Małgorzata; Forsythe, Stephen J; Ossowska, Karolina; Dziadziuszko, Halina; Kaczyński, Zbigniew

    2015-04-30

    The O-polysaccharide (OPS) of Cronobacter sakazakii NTU 696 (Sequence Type 12) from a case of neonatal necrotizing enterocolitis was isolated from the polysaccharide fraction obtained after lipopolysaccharide (LPS) hydrolysis. Purified OPS was analyzed by NMR spectroscopy ((1)H, COSY, TOCSY, NOESY, HSQC, HSQC-TOCSY and HMBC experiments) and chemical methods. Obtained monosaccharide derivatives analyzed by gas chromatography and gas chromatography-mass spectrometry allowed the identification of six sugar components. Performed experiments enabled to establish a structure of the OPS repeating unit of C. sakazakii NTU 696, as: [structure: see text]. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Monitoring ultraviolet (UV) radiation inactivation of Cronobacter sakazakii in dry infant formula using Fourier transform infrared spectroscopy.

    PubMed

    Liu, Qian; Lu, Xiaonan; Swanson, Barry G; Rasco, Barbara A; Kang, Dong-Hyun

    2012-01-01

    Cronobacter sakazakii is an opportunistic pathogen associated with dry infant formula presenting a high risk to low birth weight neonates. The inactivation of C. sakazakii in dry infant formula by ultraviolet (UV) radiation alone and combined with hot water treatment at temperatures of 55, 60, and 65 °C were applied in this study. UV radiation with doses in a range from 12.1 ± 0.30 kJ/m² to 72.8 ± 1.83 kJ/m² at room temperature demonstrated significant inactivation of C. sakazakii in dry infant formula (P < 0.05). UV radiation combining 60 °C hot water treatment increased inactivation of C. sakazakii cells significantly (P < 0.05) in reconstituted infant formula. Significant effects of UV radiation on C. sakazakii inactivation kinetics (D value) were not observed in infant formula reconstituted in 55 and 65 °C water (P > 0.05). The inactivation mechanism was investigated using vibrational spectroscopy. Infrared spectroscopy detected significant stretching mode changes of macromolecules on the basis of spectral features, such as DNA, proteins, and lipids. Minor changes on cell membrane composition of C. sakazakii under UV radiation could be accurately and correctly monitored by infrared spectroscopy coupled with 2nd derivative transformation and principal component analysis. © 2011 Institute of Food Technologists®

  8. A Novel Bacteriophage Targeting Cronobacter sakazakii Is a Potential Biocontrol Agent in Foods

    PubMed Central

    Lee, Ju-Hoon; Bai, Jaewoo; Shin, Hakdong; Kim, Yeran; Park, Bookyung; Heu, Sunggi

    2015-01-01

    Cronobacter sakazakii is an important pathogen that causes high mortality in infants. Due to its occasional antibiotic resistance, a bacteriophage approach might be an alternative effective method for the control of this pathogen. To develop a novel biocontrol agent using bacteriophages, the C. sakazakii-infecting phage CR5 was newly isolated and characterized. Interestingly, this phage exhibited efficient and relatively durable host lysis activity. In addition, a specific gene knockout study and subsequent complementation experiment revealed that this phage infected the host strain using the bacterial flagella. The complete genome sequence analysis of phage CR5 showed that its genome contains 223,989 bp of DNA, including 231 predicted open reading frames (ORFs), and it has a G+C content of 50.06%. The annotated ORFs were classified into six functional groups (structure, packaging, host lysis, DNA manipulation, transcription, and additional functions); no gene was found to be related to virulence or toxin or lysogen formation, but >80% of the predicted ORFs are unknown. In addition, a phage proteomic analysis using SDS-PAGE and matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) revealed that seven phage structural proteins are indeed present, supporting the ORF predictions. To verify the potential of this phage as a biocontrol agent against C. sakazakii, it was added to infant formula milk contaminated with a C. sakazakii clinical isolate or food isolate, revealing complete growth inhibition of the isolates by the addition of phage CR5 when the multiplicity of infection (MOI) was 105. PMID:26497465

  9. Prevalence and Characterization of Cronobacter sakazakii in Retail Milk-Based Infant and Baby Foods in Shaanxi, China.

    PubMed

    Li, Zhen; Ge, Wupeng; Li, Keting; Gan, Jing; Zhang, Yifan; Zhang, Qiang; Luo, Rong; Chen, Limin; Liang, Yi; Wang, Qianning; Xi, Meili; Xia, Xiaodong; Wang, Xin; Yang, Baowei

    2016-04-01

    Cronobacter sakazakii (formerly Enterobacter sakazakii) is an opportunistic pathogen that causes meningitis, sepsis, and necrotizing enterocolitis in neonates and infants through consumption of contaminated milk-based foods. In this study, the prevalence of C. sakazakii in 705 retail milk-based infant and baby food samples was investigated in 12 cities in Shaanxi, China, in 2010 and 2012. One hundred and nineteen samples (16.9%) were C. sakazakii positive. The isolates were further characterized for antimicrobial susceptibility to 14 antibiotics, pulsed-field gel electrophoresis profiles, and presence of the virulence genes. Samples of brand W, Y, A, and G in 2010 and 2012 were C. sakazakii positive. All isolates recovered in 2010 and 2012 were susceptible to levofloxacin and cefoperazone. In 2012, no isolate was resistant to gentamicin, cefoxitin, chloramphenicol, gatifloxacin, ciprofloxacin, and ceftriaxone. Antibiotic resistance of the isolates was most commonly found to rifampicin, amoxicillin-clavulanic acid, streptomycin, tetracycline, and ampicillin in both 2010 and 2012, except to trimethoprim/sulfamethoxazole in 2012. Pulsed-field gel electrophoresis profiles indicated that C. sakazakii isolates were genotypically diverse, although these isolates were prevalent in infant and baby foods with the same brand. A total of 34 virulence gene profiles of the C. sakazakii isolates in 2010 and 2012 were detected. Isolates that co-carried hly-ompX-eitCBAD-iucABCD/iutA genes in 2012 were significantly (p < 0.05) more prevalent than those in 2010. The results added new epidemiological evidence for the widespread occurrence of C. sakazakii in retail milk-based infant and baby foods and this should be an indicator of potential health risk for consumers.

  10. Inhibition of Cronobacter sakazakii Adhesion to Caco-2 Cells by Commercial Dairy Powders and Raw Buttermilk.

    PubMed

    Ripollés, Daniel; Harouna, Saidou; Parrón, José A; Arenales, Irene; Calvo, Miguel; Pérez, María D; Sánchez, Lourdes

    2017-02-08

    Cronobacter sakazakii is a foodborne pathogen that has been associated with severe infections, mainly in neonates. The binding of this bacterium to host cell surfaces represents the first step in the pathogenesis of disease. An ELISA-based assay has been developed using a polyclonal antiserum against C. sakazakii to determine its adhesion to Caco-2 cells. The antiserum used recognized many of the outer membrane proteins of C. sakazakii. A positive correlation was found between the absorbance values obtained by ELISA and the number of bacteria adhered to cells determined by plate counting. The inhibitory effect on bacterial adhesion to cells observed with some dairy products was concentration-dependent. Commercial buttermilk caused the maximal reduction of the adhesion percentage (33.0 ± 5.07) at the highest concentration assayed (20 mg/mL), followed by butter serum (31.9 ± 5.36), skim milk (30.4 ± 5.07), and raw buttermilk (25.6 ± 3.80). In some cases, significant differences (p < 0.05) were found in the inhibition exerted by the different products evaluated. The results obtained in this study demonstrate that dairy products contain some components with the ability to inhibit the adhesion of C. sakazakii to Caco-2 cells.

  11. Comparative Analysis of Genome Sequences Covering the Seven Cronobacter Species

    PubMed Central

    Cummings, Craig A.; Shih, Rita; Degoricija, Lovorka; Rico, Alain; Brzoska, Pius; Hamby, Stephen E.; Masood, Naqash; Hariri, Sumyya; Sonbol, Hana; Chuzhanova, Nadia; McClelland, Michael; Furtado, Manohar R.; Forsythe, Stephen J.

    2012-01-01

    Background Species of Cronobacter are widespread in the environment and are occasional food-borne pathogens associated with serious neonatal diseases, including bacteraemia, meningitis, and necrotising enterocolitis. The genus is composed of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. dublinensis, C. muytjensii, C. universalis, and C. condimenti. Clinical cases are associated with three species, C. malonaticus, C. turicensis and, in particular, with C. sakazakii multilocus sequence type 4. Thus, it is plausible that virulence determinants have evolved in certain lineages. Methodology/Principal Findings We generated high quality sequence drafts for eleven Cronobacter genomes representing the seven Cronobacter species, including an ST4 strain of C. sakazakii. Comparative analysis of these genomes together with the two publicly available genomes revealed Cronobacter has over 6,000 genes in one or more strains and over 2,000 genes shared by all Cronobacter. Considerable variation in the presence of traits such as type six secretion systems, metal resistance (tellurite, copper and silver), and adhesins were found. C. sakazakii is unique in the Cronobacter genus in encoding genes enabling the utilization of exogenous sialic acid which may have clinical significance. The C. sakazakii ST4 strain 701 contained additional genes as compared to other C. sakazakii but none of them were known specific virulence-related genes. Conclusions/Significance Genome comparison revealed that pair-wise DNA sequence identity varies between 89 and 97% in the seven Cronobacter species, and also suggested various degrees of divergence. Sets of universal core genes and accessory genes unique to each strain were identified. These gene sequences can be used for designing genus/species specific detection assays. Genes encoding adhesins, T6SS, and metal resistance genes as well as prophages are found in only subsets of genomes and have contributed considerably to the variation of

  12. Development of Multiplex Real-time PCR with Internal Amplification Control for Simultaneous Detection of Salmonella and Cronobacter sakazakii in Powdered Infant Formula.

    USDA-ARS?s Scientific Manuscript database

    Contamination of powdered infant formula (PIF) by the bacteria Cronobacter sakazakii and Salmonella enterica was deemed a matter of great concern by the World Health Organization and the Food and Agriculture Organization of the United Nations in 2004. Therefore, we developed a rapid and sensitive m...

  13. Prevalence, Molecular Characterization, and Antibiotic Susceptibility of Cronobacter sakazakii Isolates from Powdered Infant Formula Collected from Chinese Retail Markets

    PubMed Central

    Fei, Peng; Jiang, Yichao; Jiang, Yan; Yuan, Xiujuan; Yang, Tongxiang; Chen, Junliang; Wang, Ziyuan; Kang, Huaibin; Forsythe, Stephen J.

    2017-01-01

    Cronobacter sakazakii is an opportunistic pathogen that causes severe infections in neonates and infants through contaminated powdered infant formula (PIF). Therefore, the aim of this study was a large-scale study on determine the prevalence, molecular characterization and antibiotic susceptibility of C. sakazakii isolates from PIF purchased from Chinese retail markets. Two thousand and twenty PIF samples were collected from different institutions. Fifty-six C. sakazakii strains were isolated, and identified using fusA sequencing analysis, giving a contamination rate of 2.8%. Multilocus sequence typing (MLST) was more discriminatory than other genotyping methods. The C. sakazakii isolates were divided into 14 sequence types (STs) by MLST, compared with only seven clusters by ompA and rpoB sequence analysis, and four C. sakazakii serotypes by PCR-based O-antigen serotyping. C. sakazakii ST4 (19/56, 33.9%), ST1 (12/56, 21.4%), and ST64 (11/56, 16.1%) were the dominant sequence types isolated. C. sakazakii serotype O2 (34/56, 60.7%) was the primary serotype, along with ompA6 and rpoB1 as the main allele profiles, respectively. Antibiotic susceptibility testing indicated that all C. sakazakii isolates were susceptible to ampicillin-sulbactam, cefotaxime, ciprofloxacin, meropenem, tetracycline, piperacillin-tazobactam, and trimethoprim-sulfamethoxazole. The majority of C. sakazakii strains were susceptible to chloramphenicol and gentamicin (87.5 and 92.9%, respectively). In contrast, 55.4% C. sakazakii strains were resistant to cephalothin. In conclusion, this large-scale study revealed the prevalence and characteristics of C. sakazakii from PIF in Chinese retail markets, demonstrating a potential risk for neonates and infants, and provide a guided to effective control the contamination of C. sakazakii in production process. PMID:29089940

  14. Short communication: Effects of high-pressure processing on the inactivity of Cronobacter sakazakii in whole milk and skim milk samples.

    PubMed

    Jiao, Rui; Gao, Jina; Li, Yinxiang; Zhang, Xiyan; Zhang, Maofeng; Ye, Yingwang; Wu, Qingping; Fan, Hongying

    2016-10-01

    Powdered infant formula is considered as the main transmission vehicle for Cronobacter sakazakii infections including meningitis, septicemia, and necrotizing enterocolitis. The effects of high-pressure processing treatment on inactivation of C. sakazakii ranging from 100 to 400 MPa for 3.0, 5.0, and 7.0 min in whole milk and skim milk were studied. Significant differences in inactivation of C. sakazakii were observed in milk samples under different pressures for 3 to 7 min compared with untreated samples, and C. sakazakii was not detected after 400 MPa for 3 min. The lethality rates of C. sakazakii cells in whole and skim milk with an initial level of 10(4) cfu/mL after 100 and 200 MPa treatments were not significantly different, but relatively higher lethality rates were found in whole milk after 300 MPa treatment than in skim milk. Finally, the scanning electron micrographs indicated that cellular envelope and intracellular damage of C. sakazakii cells were apparent after 300 and 400 MPa for 5.0 min compared with the untreated cells, and a progressive increase of injured cells with increased pressure treatment was found. It was concluded that C. sakazakii was sensitive to high-pressure processing treatment and that high-pressure processing treatment with 400 MPa for 3.0 min can be used to control C. sakazakii contamination in milk samples. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. Occurrence of Cronobacter spp. in Dried Foods, Fresh Vegetables and Soil.

    PubMed

    Ueda, Shigeko

    2017-01-01

     The present study surveyed the occurrence of Cronobacter spp. in dried foods including milk powder, spices and herbs and others, and fresh vegetables commercially available in markets, and ground soil materials for the agriculture. Cronobacter spp. were isolated from 15% of 33 spice and herb samples and 3% of 36 taste foods, and these were C. turicensis, C. malonaticus, C. sakazakii and C. dubliensis. Cronobacter spp. from fresh vegetables were detected in 12% of field vegetables and 13% of hydroponic vegetables. C. turicensis was prevalent in field vegetables, and C. malonaticus was in hydroponic ones. And, Cronobacter spp. in shredded vegetables were detected from 44% of 9 samples, and these were C. dubliensis, C. turicensis and C. sakazakii. Also, Cronobacter spp. in soil from rice field, vegetable field and sandpits were predominantly C. sakazakii and C. malonaticus.

  16. Decreasing Enterobacter sakazakii (Cronobacter spp.) food contamination level with bacteriophages: prospects and problems

    PubMed Central

    Zuber, Sophie; Boissin‐Delaporte, Catherine; Michot, Lise; Iversen, Carol; Diep, Benjamin; Brüssow, Harald; Breeuwer, Pieter

    2008-01-01

    Summary Enterobacter sakazakii (Cronobacter spp.) is an opportunistic pathogen, which can cause rare, but life‐threatening infections in neonates and infants through feeding of a contaminated milk formula. We isolated 67 phages from environmental samples and tested their lytic host range on a representative collection of 40 E. sakazakii strains. A cocktail of five phages prevented the outgrowth of 35 out of 40 test strains in artificially contaminated infant formula. Two E. sakazakii phages represented prolate head Myoviridae. Molecular tests identified them as close relatives of Escherichia coli phage T4. The remaining three phages represented isometric head Myoviridae with large genome size of 140 and 200 kb, respectively, which belonged to two different DNA hybridization groups. A high dose of 108 pfu ml−1 of phage could effectively sterilize a broth contaminated with both high and low pathogen counts (106 and 102 cfu ml−1). In contrast, broth inoculated with 104 phage and 102 bacteria per ml first showed normal bacterial growth until reaching a cell titre of 105 cfu ml−1. Only when crossing this threshold, phage replication started, but it could not reduce the contamination level below 100 cfu ml−1. Phages could be produced with titres of 1010 pfu ml−1 in broth culture, but they were not stable upon freeze‐drying. Addition of trehalose or milk formula stabilized the phage preparation, which then showed excellent storage stability even at elevated temperature. PMID:21261874

  17. Emergence of Colistin Resistance Gene mcr-1 in Cronobacter sakazakii Producing NDM-9 and in Escherichia coli from the Same Animal.

    PubMed

    Liu, Bao-Tao; Song, Feng-Jing; Zou, Ming; Hao, Zhi-Hui; Shan, Hu

    2017-02-01

    We report the presence of mcr-1 in Escherichia coli and carbapenem-resistant Cronobacter sakazakii from the same diseased chicken. The mcr-1 gene linked with ISApl1 was located on two different IncI2 plasmids, including one multidrug plasmid in E. coli, whereas fosA3-bla NDM-9 was on an IncB/O plasmid in C. sakazakii The development of the fosA3-bla NDM-9 resistance region was mediated by IS26 The colocation of mcr-1 or bla NDM-9 with other resistance genes will accelerate the dissemination of the two genes. Copyright © 2017 American Society for Microbiology.

  18. Validation of radio-frequency dielectric heating system for destruction of Cronobacter sakazakii and Salmonella species in nonfat dry milk.

    PubMed

    Michael, M; Phebus, R K; Thippareddi, H; Subbiah, J; Birla, S L; Schmidt, K A

    2014-12-01

    Cronobacter sakazakii and Salmonella species have been associated with human illnesses from consumption of contaminated nonfat dry milk (NDM), a key ingredient in powdered infant formula and many other foods. Cronobacter sakazakii and Salmonella spp. can survive the spray-drying process if milk is contaminated after pasteurization, and the dried product can be contaminated from environmental sources. Compared with conventional heating, radio-frequency dielectric heating (RFDH) is a faster and more uniform process for heating low-moisture foods. The objective of this study was to design an RFDH process to achieve target destruction (log reductions) of C. sakazakii and Salmonella spp. The thermal destruction (decimal reduction time; D-value) of C. sakazakii and Salmonella spp. in NDM (high-heat, HH; and low-heat, LH) was determined at 75, 80, 85, or 90 °C using a thermal-death-time (TDT) disk method, and the z-values (the temperature increase required to obtain a decimal reduction of the D-value) were calculated. Time and temperature requirements to achieve specific destruction of the pathogens were calculated from the thermal destruction parameters, and the efficacy of the RFDH process was validated by heating NDM using RFDH to achieve the target temperatures and holding the product in a convection oven for the required period. Linear regression was used to determine the D-values and z-values. The D-values of C. sakazakii in HH- and LH-NDM were 24.86 and 23.0 min at 75 °C, 13.75 and 7.52 min at 80 °C, 8.0 and 6.03 min at 85 °C, and 5.57 and 5.37 min at 90 °C, respectively. The D-values of Salmonella spp. in HH- and LH-NDM were 23.02 and 24.94 min at 75 °C, 10.45 and 12.54 min at 80 °C, 8.63 and 8.68 min at 85 °C, and 5.82 and 4.55 min at 90 °C, respectively. The predicted and observed destruction of C. sakazakii and Salmonella spp. were in agreement, indicating that the behavior of the organisms was similar regardless of the heating system (conventional vs

  19. Gold nanoparticle-based enhanced lateral flow immunoassay for detection of Cronobacter sakazakii in powdered infant formula.

    PubMed

    Pan, Ruili; Jiang, Yujun; Sun, Luhong; Wang, Rui; Zhuang, Kejin; Zhao, Yueming; Wang, Hui; Ali, Md Aslam; Xu, Honghua; Man, Chaoxin

    2018-05-01

    Cronobacter sakazakii is an opportunistic foodborne pathogen that can infect newborns through powdered infant formula (PIF). In this study, we developed a novel enhanced lateral flow immunoassay (LFA) with enhanced sensitivity for detection of C. sakazakii in PIF by the naked eye. The proposed strategy for signal enhancement of the traditional LFA used concentrated gold nanoparticles (AuNP) as the enhancer to conjugate with capture antibodies, which could increase the immobilized capture antibodies concentration at the detection zone to improve capture efficiency. Besides, the detection signal was further amplified by accumulated AuNP as the C. sakazakii labeled with AuNP probes was captured by antibodies conjugated with enhancer at the test line. We also studied the effect of different concentrations of capture antibodies and concentrated AuNP on detection performance, and found that 2.2 mg/mL of capture antibodies and 0.06 nM concentrated AuNP were the optimal combination that could avoid a false-positive signal and maximally amplify the detection signal of the enhanced LFA. Using this strategy, the detection sensitivity of the enhanced LFA was 10 3 cfu/mL and improved 100-fold compared with traditional LFA. The strip was highly specific to C. sakazakii, and the time for detection of C. sakazakii in PIF was shortened by 3 h. In summary, the enhanced LFA developed by the addition of concentrated AuNP as the enhancer can be used as a sensitive, rapid, visual qualitative and point-of-care test method for detecting target analytes. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Sub-lethal heat treatment affects the tolerance of Cronobacter sakazakii BCRC 13988 to various organic acids, simulated gastric juice and bile solution.

    PubMed

    Hsiao, Wan-Ling; Ho, Wei-Li; Chou, Cheng-Chun

    2010-12-15

    Cronobacter spp., formerly Enterobacter sakazakii, are considered emerging opportunistic pathogens and the etiological agent of life-threatening bacterial infections in infants. In the present study, C. sakazakii BCRC 13988 was first subjected to sub-lethal heat treatment at 47°C for 15min. Survival rates of the heat-shocked and non-shocked C. sakazakii cells in phosphate buffer solution (PBS, pH 4.0) containing organic acids (e.g. acetic, propionic, citric, lactic or tartaric acid), simulated gastric juice (pH 2.0-4.0), and bile solution (0.5 and 2.0%) were examined. Results revealed that sub-lethal heat treatment enhanced the test organism's tolerance to organic acids, although the extent of increased acid tolerance varied with the organic acid examined. Compared with the control cells, heat-shocked C. sakazakii cells after 120-min of exposure, exhibited the largest increase in tolerance in the lactic acid-containing PBS. Furthermore, although heat shock did not affect the behavior of C. sakazakii in bile solution, it increased the test organism's survival when exposed to simulated gastric juice with a pH of 3.0-4.0. Copyright © 2010. Published by Elsevier B.V.

  1. Structural and genetic relationships of closely related O-antigens of Cronobacter spp. and Escherichia coli: C. sakazakii G2594 (serotype O4)/E. coli O103 and C. malonaticus G3864 (serotype O1)/E. coli O29.

    PubMed

    Shashkov, Alexander S; Wang, Min; Turdymuratov, Eldar M; Hu, Shaohui; Arbatsky, Nikolay P; Guo, Xi; Wang, Lei; Knirel, Yuriy A

    2015-03-02

    O-Antigen (O-polysaccharide) variation is the basis for bacterial serotyping and is important in bacterial virulence and niche adaptation. In this work, we present structural and genetic evidences for close relationships between the O-antigens of the Cronobacter spp. and Escherichia coli. Cronobacter sakazakii G2594 (serotype O4) and Cronobacter malonaticus G3864 (serotype O1) are structurally related to those of E. coli O103 and O29, respectively, and some other members of the Enterobacteriaceae family differing in the patterns of lateral glucosylation (C. sakazakii G2594) or O-acetylation (C. malonaticus G3864). The O-antigen gene clusters of the corresponding Cronobacter and E. coli strains contain the same genes with high-level similarity, and the structural differences within both O-antigen pairs were suggested to be due to modification genes carried by prophages. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Inhibition of Cronobacter sakazakii by heat labile bacteriocins produced by probiotic LAB isolated from healthy infants.

    PubMed

    Awaisheh, Saddam S; Al-Nabulsi, Anas A; Osaili, Tareq M; Ibrahim, Salam; Holley, Richard

    2013-09-01

    Cronobacter sakazakii is an opportunistic pathogen that can cause bacteremia, meningitis, and necrotizing enterocolitis, most often in neonates with case-fatality rates that may reach 80%. The antimicrobial activity of lactic acid bacteria against a wide range of foodborne pathogens is well-established in different types of food products. The objective of the current study was to investigate the antibacterial activity of Lactobacillus acidophilus and L. casei isolated from feces of healthy infants against different strains of C. sakazakii in agar and a rehydrated infant milk formula (RIMF) model. The inhibition zones of C. sakazakii around L. acidophilus or L. casei ranged from 22 to 32 mm on eMan Rogosa Sharpe (MRS) agar under aerobic conditions, while a slight reduction in antibacterial activity was noted on modified MRS (0.2% glucose) under anaerobic conditions. It was observed that pH-neutralized cell-free supernatant (CFS) of L. acidophilus or L. casei was inhibitory against tested C. sakazakii strains. The inhibition zones of neutralized CFS were lower than the antibacterial activities of live cultures. The antibacterial activity of CFS was abolished when CFS from L. acidophilus or L. casei was heated at 60 or 80 °C for either 10 min or 2 h, or treated with trypsin or pepsin. This was considered strong evidence that the inhibition was due to the production of bacteriocins by L. casei and L. acidophilus. Both the CFS and active growing cells of L. casei and L. acidophilus were able to reduce the viability of C. sakazakii in the RIMF model. The results may extend the use of natural antimicrobials instead of conventional preservation methods to improve the safety of RIMF. © 2013 Institute of Food Technologists®

  3. Rapid and sensitive detection of Cronobacter spp. (previously Enterobacter sakazakii) in food by duplex PCR combined with capillary electrophoresis-laser-induced fluorescence detector.

    PubMed

    Ruan, Jia; Li, Ming; Liu, Ya-Pan; Li, Yuan-Qian; Li, Yong-Xin

    2013-03-15

    Cronobacter spp. (Enterobacter sakazakii) is an emerging opportunistic pathogen with a 40-80% mortality rate in infants and immunocompromised crowd resulting from the consumption of contaminated food. A novel method for detecting Cronobacter spp. in food samples by duplex polymerase chain reaction (PCR) in combination with capillary electrophoresis-laser induced fluorescence (CE-LIF) detector has been developed. The specific gene sequences of 16S-23S rDNA internal transcribed spacer (ITS) and the outer membrane protein A (OmpA) of Cronobacter spp. were amplified by duplex PCR. The PCR products were separated and determined sensitively by CE-LIF within 12min. The relative standard deviations of migration time for the detected DNA fragments were 2.01-2.91%. The detection limit was as low as 1.6×10(1)cfu/mL of Cronobacter spp. Besides, the specificity of the method was verified by 24 non-Cronobacter bacterial strains. A total of 120 commercial infant food formula were tested for the presence of Cronobacter spp. by using the proposed method. This current study demonstrates that the combination of CE-LIF method with duplex PCR is rapid, sensitive and environmental friendly, and has the potential to be adapted for the routine detection of Cronobacter spp. in food samples. To the best of our knowledge, this is the first use of CE-LIF for the detection of Cronobacter spp. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  4. Rapid Detection and Simultaneous Genotyping of Cronobacter spp. (formerly Enterobacter sakazakii) in Powdered Infant Formula Using Real-time PCR and High Resolution Melting (HRM) Analysis

    PubMed Central

    Cai, Xian-Quan; Yu, Hai-Qiong; Ruan, Zhou-Xi; Yang, Lei-Liang; Bai, Jian-Shan; Qiu, De-Yi; Jian, Zhi-Hua; Xiao, Yi-Qian; Yang, Jie-Yang; Le, Thanh Hoa; Zhu, Xing-Quan

    2013-01-01

    Cronobacter spp. is an emerging pathogen that causes meningitis, sepsis, bacteremia, and necrotizing enterocolitis in neonates and children. The present study developed an assay integrating real-time PCR and high resolution melting (HRM) analysis targeting the OmpA gene for the specific detection and rapid identification of Cronobacter spp. (formerly Enterobacter sakazakii) in powdered infant formula. Eleven Cronobacter field isolates and 25 reference strains were examined using one pair of primers, having the accuracy of 100% in reference to conventional methods. The assay was proved to be highly sensitive with a detection limit of 102 CFU/ml without pre-enrichment, and highly concordant (100%) when compared with ISO-IDF 22964 in 89 actual samples. The method performed for Cronobacter spp. detection was less than 24 h, drastically shortened, compared to several days using standard culturing method, it is probe-free and reduces a risk of PCR carryover. Moreover, all Cronobacter strains examined in this study were genotyped into two species according to their HRM profiles. The established method should provide a molecular tool for direct detection and simultaneous genotyping of Cronobacter spp. in powdered infant formula. PMID:23825624

  5. Rapid detection and simultaneous genotyping of Cronobacter spp. (formerly Enterobacter sakazakii) in powdered infant formula using real-time PCR and high resolution melting (HRM) analysis.

    PubMed

    Cai, Xian-Quan; Yu, Hai-Qiong; Ruan, Zhou-Xi; Yang, Lei-Liang; Bai, Jian-Shan; Qiu, De-Yi; Jian, Zhi-Hua; Xiao, Yi-Qian; Yang, Jie-Yang; Le, Thanh Hoa; Zhu, Xing-Quan

    2013-01-01

    Cronobacter spp. is an emerging pathogen that causes meningitis, sepsis, bacteremia, and necrotizing enterocolitis in neonates and children. The present study developed an assay integrating real-time PCR and high resolution melting (HRM) analysis targeting the OmpA gene for the specific detection and rapid identification of Cronobacter spp. (formerly Enterobacter sakazakii) in powdered infant formula. Eleven Cronobacter field isolates and 25 reference strains were examined using one pair of primers, having the accuracy of 100% in reference to conventional methods. The assay was proved to be highly sensitive with a detection limit of 10(2) CFU/ml without pre-enrichment, and highly concordant (100%) when compared with ISO-IDF 22964 in 89 actual samples. The method performed for Cronobacter spp. detection was less than 24 h, drastically shortened, compared to several days using standard culturing method, it is probe-free and reduces a risk of PCR carryover. Moreover, all Cronobacter strains examined in this study were genotyped into two species according to their HRM profiles. The established method should provide a molecular tool for direct detection and simultaneous genotyping of Cronobacter spp. in powdered infant formula.

  6. Short communication: Effects of vacuum freeze-drying on inactivation of Cronobacter sakazakii ATCC29544 in liquid media with different initial inoculum levels.

    PubMed

    Jiao, Rui; Gao, Jina; Zhang, Xiyan; Zhang, Maofeng; Chen, Jiren; Wu, Qingping; Zhang, Jumei; Ye, Yingwang

    2017-03-01

    Vacuum freeze-drying is an important food-processing technology for valid retention of nutrients and bioactive compounds. Cronobacter sakazakii has been reported to be associated with severe infections in neonates through consumption of contaminated powdered infant formula. In this study, effects of vacuum freeze-drying treatment for 12, 24, and 36 h on inactivation of C. sakazakii with different initial inoculum levels in sterile water, tryptic soy broth (TSB), skim milk, and whole milk were determined. Results indicated that the lethality rate of C. sakazakii in each sample increased with the extension of vacuum freeze-drying time. With initial inoculum levels of 10 2 and 10 3 cfu/mL, the survival of C. sakazakii in different liquid media was significantly affected by vacuum freeze-drying for 12, 24, and 36 h. In addition, the lethality rates of C. sakazakii in whole milk, skim milk, and TSB was significantly reduced compared with those in sterile water. Furthermore, whole milk showed the strongest protective role for C. sakazakii cells, followed by skim milk and TSB medium. Using the scanning electron microscope, the intracellular damage and obvious distortion of C. sakazakii cells were observed after vacuum freeze-drying for 24 and 36 h compared with the untreated sample, and the injured cells increased with the extension of vacuum-drying time. We concluded that inactivation of vacuum freeze-drying on C. sakazakii cells is related to the food matrix, and a combination with other methods for inactivating C. sakazakii is required for ensuring microbial safety of powdered infant formula. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. A proposed harmonized LPS molecular-subtyping scheme for Cronobacter species.

    PubMed

    Yan, Qiongqiong; Jarvis, Karen G; Chase, Hannah R; Hébert, Karine; Trach, Larisa H; Lee, Chloe; Sadowski, Jennifer; Lee, Boram; Hwang, Seongeun; Sathyamoorthy, Venugopal; Mullane, Niall; Pava-Ripoll, Monica; Iversen, Carol; Pagotto, Franco; Fanning, Séamus; Tall, Ben D

    2015-09-01

    Cronobacter are opportunistic pathogens, which cause infections in all age groups. To aid the characterization of Cronobacter in foods and environments a harmonized LPS identification scheme for molecular serotyping is needed. To this end, we studied 409 Cronobacter isolates representing the seven Cronobacter species using two previously reported molecular serotyping schemes, described here as Mullane-Jarvis (M-J) and Sun schemes. PCR analysis revealed many overlapping results that were obtained when independently applying the two serotyping schemes. There were complete agreements between the two PCR schemes for Cronobacter sakazakii (Csak) O:1, Csak O:3, and Csak O:7 serotypes. However, only thirty-five of 41 Csak O:4 strains, identified using the M-J scheme, were PCR-positive with the Sun scheme primers. Also the Sun scheme Csak O:5 primers failed to identify this serotype in any of the C. sakazakii strains tested, but did recognize seven Cronobacter turicensis strains, which were identified as Ctur O:3 using the M-J scheme. Similarly, the Sun scheme Csak O:6 primers recognized 30 Cronobacter malonaticus O:2 strains identified with the M-J scheme, but failed to identify this serotype in any C. sakazakii strain investigated. In this report, these findings are summarized and a harmonized molecular-serotyping scheme is proposed which is predicated on the correct identification of Cronobacter species, prior to serotype determination. In summary, fourteen serotypes were identified using the combined protocol, which consists of Csak O:1-O:4, and Csak O:7; Cmal O:1-O:2; Cdub O:1-O:2, Cmuy O:1-O:2, Cuni O:1, as well as Ctur O:1 and Ctur O:3. Published by Elsevier Ltd.

  8. Multilocus Sequence Typing of Cronobacter Strains Isolated from Retail Foods and Environmental Samples.

    PubMed

    Killer, Jiří; Skřivanová, Eva; Hochel, Igor; Marounek, Milan

    2015-06-01

    Cronobacter spp. are bacterial pathogens that affect children and immunocompromised adults. In this study, we used multilocus sequence typing (MLST) to determine sequence types (STs) in 11 Cronobacter spp. strains isolated from retail foods, 29 strains from dust samples obtained from vacuum cleaners, and 4 clinical isolates. Using biochemical tests, species-specific polymerase chain reaction, and MLST analysis, 36 strains were identified as Cronobacter sakazakii, and 6 were identified as Cronobacter malonaticus. In addition, one strain that originated from retail food and one from a dust sample from a vacuum cleaner were identified on the basis of MLST analysis as Cronobacter dublinensis and Cronobacter turicensis, respectively. Cronobacter spp. strains isolated from the retail foods were assigned to eight different MLST sequence types, seven of which were newly identified. The strains isolated from the dust samples were assigned to 7 known STs and 14 unknown STs. Three clinical isolates and one household dust isolate were assigned to ST4, which is the predominant ST associated with neonatal meningitis. One clinical isolate was classified based on MLST analysis as Cronobacter malonaticus and belonged to an as-yet-unknown ST. Three strains isolated from the household dust samples were assigned to ST1, which is another clinically significant ST. It can be concluded that Cronobacter spp. strains of different origin are genetically quite variable. The recovery of C. sakazakii strains belonging to ST1 and ST4 from the dust samples suggests the possibility that contamination could occur during food preparation. All of the novel STs and alleles for C. sakazakii, C. malonaticus, C. dublinensis, and C. turicensis determined in this study were deposited in the Cronobacter MLST database available online ( http://pubmlst.org/cronobacter/).

  9. Conditioned medium from Bifidobacteria infantis protects against Cronobacter sakazakii-induced intestinal inflammation in newborn mice

    PubMed Central

    Weng, Meiqian; Ganguli, Kriston; Zhu, Weishu; Shi, Hai Ning

    2014-01-01

    Necrotizing enterocolitis (NEC) is associated with a high morbidity and mortality in very low birth weight infants. Several hypotheses regarding the pathogenesis of NEC have been proposed but to date no effective treatment is available. Previous studies suggest that probiotic supplementation is protective. We recently reported that probiotic (Bifidobacterium infantis) conditioned medium (PCM) has an anti-inflammatory effect in cultured fetal human intestinal cells (H4) and fetal intestine explants. In this study, we tested in vivo whether PCM protects neonatal mice from developing intestinal inflammation induced by exposure to Cronobacter sakazakii (C. sakazakii), an opportunistic pathogen associated with NEC. We found that infected neonatal mice had a significantly lower body weight than control groups. Infection led to ileal tissue damage including villous rupture, disruption of epithelial cell alignment, intestinal inflammation, apoptotic cell loss, and decreased mucus production. Pretreatment with PCM prevented infection caused decrease in body weight, attenuated enterocyte apoptotic cell death, mitigated reduced mucin production, and maintained ileal structure. Infected ileum expressed reduced levels of IκBα, which could be restored upon pretreatment with PCM. We also observed a nuclear translocation of NF-κB p65 in H4 cells exposed to C. sakazakii, which was prevented in PCM-pretreated cells. Finally, treatment of neonatal mice with PCM prior to infection sustained the capacity of ileal epithelial proliferation. This study suggests that an active component(s) released into the culture medium by B. infantis may prevent ileal damage by a pathogen linked to NEC. PMID:24627567

  10. Cronobacter species (formerly known as Enterobacter sakazakii) in powdered infant formula: a review of our current understanding of the biology of this bacterium.

    PubMed

    Yan, Q Q; Condell, O; Power, K; Butler, F; Tall, B D; Fanning, S

    2012-07-01

    Cronobacter species (formerly known as Enterobacter sakazakii) are opportunistic pathogens that can cause necrotizing enterocolitis, bacteraemia and meningitis, predominantly in neonates. Infection in these vulnerable infants has been linked to the consumption of contaminated powdered infant formula (PIF). Considerable research has been undertaken on this organism in the past number of years which has enhanced our understanding of this neonatal pathogen leading to improvements in its control within the PIF production environment. The taxonomy of the organism resulted in the recognition of a new genus, Cronobacter, which consists of seven species. This paper presents an up-to-date review of our current knowledge of Cronobacter species. Taxonomy, genome sequencing, current detection protocols and epidemiology are all discussed. In addition, consideration is given to the control of this organism in the manufacturing environment, as a first step towards reducing the occurrence of this pathogen in PIF. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  11. Evidence for a plant-associated natural habitat for Cronobacter spp.

    PubMed

    Schmid, Michael; Iversen, Carol; Gontia, Iti; Stephan, Roger; Hofmann, Andreas; Hartmann, Anton; Jha, Bhavanath; Eberl, Leo; Riedel, Kathrin; Lehner, Angelika

    2009-10-01

    Cronobacter (Enterobacter sakazakii) species are responsible for rare cases of necrotising enterocolitis and bacteraemia in infants, as well as cases of meningitis with high case fatality rates in neonates and immunocompromised infants. Some physiological features, such as the production of a yellow pigment, the formation of a gum-like extracellular polysaccharide and the ability to persist in a desiccated state, suggest an environmental niche for these organisms. To date, the natural habitat of Cronobacter spp. remains unknown. In this report, the isolation and characterisation of two Cronobacter sakazakii strains from plant roots is described. Also, the root colonisation behaviour of Cronobacter strains originating from clinical and plant sources is assessed. The nine strains investigated showed features often found in plant-associated and rhizosphere microorganisms, including solubilisation of mineral phosphate and production of indole acetic acid. Siderophore production was observed for all except one strain. In addition, the capability to endophytically colonise tomato and maize roots was demonstrated for several strains, either by fluorescence in situ hybridisation, using fluorescently labelled oligonucleotide probes, or by using strains tagged with green fluorescent protein and confocal laser scanning microscopy. The results provide evidence that plants may be the natural habitat of Cronobacter spp.

  12. Identification and Characterization of Cronobacter Iron Acquisition Systems

    PubMed Central

    Grim, C. J.; Kothary, M. H.; Gopinath, G.; Jarvis, K. G.; Beaubrun, J. Jean-Gilles; McClelland, M.; Tall, B. D.

    2012-01-01

    Cronobacter spp. are emerging pathogens that cause severe infantile meningitis, septicemia, or necrotizing enterocolitis. Contaminated powdered infant formula has been implicated as the source of Cronobacter spp. in most cases, but questions still remain regarding the natural habitat and virulence potential for each strain. The iron acquisition systems in 231 Cronobacter strains isolated from different sources were identified and characterized. All Cronobacter spp. have both the Feo and Efe systems for acquisition of ferrous iron, and all plasmid-harboring strains (98%) have the aerobactin-like siderophore, cronobactin, for transport of ferric iron. All Cronobacter spp. have the genes encoding an enterobactin-like siderophore, although it was not functional under the conditions tested. Furthermore, all Cronobacter spp. have genes encoding five receptors for heterologous siderophores. A ferric dicitrate transport system (fec system) is encoded specifically by a subset of Cronobacter sakazakii and C. malonaticus strains, of which a high percentage were isolated from clinical samples. Phylogenetic analysis confirmed that the fec system is most closely related to orthologous genes present in human-pathogenic bacterial strains. Moreover, all strains of C. dublinensis and C. muytjensii encode two receptors, FcuA and Fct, for heterologous siderophores produced by plant pathogens. Identification of putative Fur boxes and expression of the genes under iron-depleted conditions revealed which genes and operons are components of the Fur regulon. Taken together, these results support the proposition that C. sakazakii and C. malonaticus may be more associated with the human host and C. dublinensis and C. muytjensii with plants. PMID:22706064

  13. Inactivation effect of X-ray treatments on Cronobacter species (Enterobacter sakazakii) in tryptic soy broth, skim milk, low-fat milk and whole-fat milk.

    PubMed

    Mahmoud, B S M

    2009-11-01

    To determine the inactivation effect of X-ray treatments on Cronobacter (E. sakazakii) in tryptic soy broth (TSB), skim milk (0% fat), low-fat milk (1% and 2%) and whole-fat milk (3.5%). X-rays were produced using the RS 2400 generator system (Rad Source Technologies Inc.). Cronobacter (in TSB), inoculated skim milk (0% fat), low-fat milk (1% and 2% fat) and whole-fat milk (3.5% fat) were treated with 0.0, 0.1, 0.5, 0.75, 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 kGy X-ray doses. Surviving bacteria in the TSB and inoculated milk, before and after treatment, were enumerated using plating method onto trypticase soy agar. Greater than 7.0-log CFU reduction in Cronobacter population was observed with 4.0, 5.0, 6.0, 6.0 and 6.0 kGy X-ray in the TSB, skim milk, 1% fat milk, 2% fat milk and 3.5% fat milk, respectively. Treatment with X-rays significantly (P < 0.05) reduced Cronobacter to less than detectable limits (<1 log CFU ml(-1)) in skim milk at 5.0 kGy and milk with 1% fat content and greater at 6.0 kGy dose levels. The D-value for Cronobacter in TSB was significantly (P < 0.05) lower than those in milk samples. Treatment with X-rays could be an effective and safe alternative technology to control pathogenic bacteria (Cronobacter) in the dairy industry.

  14. Diversity of the Cronobacter Genus as Revealed by Multilocus Sequence Typing

    PubMed Central

    Joseph, S.; Sonbol, H.; Hariri, S.; Desai, P.; McClelland, M.

    2012-01-01

    Cronobacter (previously known as Enterobacter sakazakii) is a diverse bacterial genus consisting of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. universalis, C. muytjensii, C. dublinensis, and C. condimenti. In this study, we have used a multilocus sequence typing (MLST) approach employing the alleles of 7 genes (atpD, fusA, glnS, gltB, gyrB, infB, and ppsA; total length, 3,036 bp) to investigate the phylogenetic relationship of 325 Cronobacter species isolates. Strains were chosen on the basis of their species, geographic and temporal distribution, source, and clinical outcome. The earliest strain was isolated from milk powder in 1950, and the earliest clinical strain was isolated in 1953. The existence of seven species was supported by MLST. Intraspecific variation ranged from low diversity in C. sakazakii to extensive diversity within some species, such as C. muytjensii and C. dublinensis, including evidence of gene conversion between species. The predominant species from clinical sources was found to be C. sakazakii. C. sakazakii sequence type 4 (ST4) was the predominant sequence type of cerebral spinal fluid isolates from cases of meningitis. PMID:22785185

  15. Putative Inv Is Essential for Basolateral Invasion of Caco-2 Cells and Acts Synergistically with OmpA To Affect In Vitro and In Vivo Virulence of Cronobacter sakazakii ATCC 29544

    PubMed Central

    Chandrapala, Dilini; Kim, Kyumson; Choi, Younho; Senevirathne, Amal; Kang, Dong-Hyun; Ryu, Sangryeol

    2014-01-01

    Cronobacter sakazakii is an opportunistic pathogen that causes neonatal meningitis and necrotizing enterocolitis. Its interaction with intestinal epithelium is important in the pathogenesis of enteric infections. In this study, we investigated the involvement of the inv gene in the virulence of C. sakazakii ATCC 29544 in vitro and in vivo. Sequence analysis of C. sakazakii ATCC 29544 inv revealed that it is different from other C. sakazakii isolates. In various cell culture models, an Δinv deletion mutant showed significantly lowered invasion efficiency, which was restored upon genetic complementation. Studying invasion potentials using tight-junction-disrupted Caco-2 cells suggested that the inv gene product mediates basolateral invasion of C. sakazakii ATCC 29544. In addition, comparison of invasion potentials of double mutant (ΔompA Δinv) and single mutants (ΔompA and Δinv) provided evidence for an additive effect of the two putative outer membrane proteins. Finally, the importance of inv and the additive effect of putative Inv and OmpA were also proven in an in vivo rat pup model. This report is the first to demonstrate two proteins working synergistically in vitro, as well as in vivo in C. sakazakii pathogenesis. PMID:24549330

  16. Putative Inv is essential for basolateral invasion of Caco-2 cells and acts synergistically with OmpA to affect in vitro and in vivo virulence of Cronobacter sakazakii ATCC 29544.

    PubMed

    Chandrapala, Dilini; Kim, Kyumson; Choi, Younho; Senevirathne, Amal; Kang, Dong-Hyun; Ryu, Sangryeol; Kim, Kwang-Pyo

    2014-05-01

    Cronobacter sakazakii is an opportunistic pathogen that causes neonatal meningitis and necrotizing enterocolitis. Its interaction with intestinal epithelium is important in the pathogenesis of enteric infections. In this study, we investigated the involvement of the inv gene in the virulence of C. sakazakii ATCC 29544 in vitro and in vivo. Sequence analysis of C. sakazakii ATCC 29544 inv revealed that it is different from other C. sakazakii isolates. In various cell culture models, an Δinv deletion mutant showed significantly lowered invasion efficiency, which was restored upon genetic complementation. Studying invasion potentials using tight-junction-disrupted Caco-2 cells suggested that the inv gene product mediates basolateral invasion of C. sakazakii ATCC 29544. In addition, comparison of invasion potentials of double mutant (ΔompA Δinv) and single mutants (ΔompA and Δinv) provided evidence for an additive effect of the two putative outer membrane proteins. Finally, the importance of inv and the additive effect of putative Inv and OmpA were also proven in an in vivo rat pup model. This report is the first to demonstrate two proteins working synergistically in vitro, as well as in vivo in C. sakazakii pathogenesis.

  17. Occurrence, Genotyping, and Antibiotic Susceptibility of Cronobacter spp. in Drinking Water and Food Samples from Northeast China.

    PubMed

    Fei, Peng; Jiang, Yichao; Gong, Shaoying; Li, Ran; Jiang, Yan; Yuan, Xiujuan; Wang, Ziyuan; Kang, Huaibin; Ali, Md Aslam

    2018-02-23

    Cronobacter species (formerly Enterobacter sakazakii) are emerging opportunistic bacterial pathogens that can infect both infants and adults. This study was conducted to isolate and genotype diverse Cronobacter species from drinking water, chilled fresh pork, powdered infant formula, instant noodles, cookies, fruits, vegetables, and dishes in Northeast China and to evaluate the antibiotic resistance and susceptibility of the isolates. Thirty-four Cronobacter strains were isolated and identified: 21 C. sakazakii isolates (61.8%), 10 C. malonaticus isolates (29.4%), 2 C. dublinensis isolates (5.9%), and 1 C. turicensis isolate (2.9%). These isolates were further divided into 15 sequence types (STs) by multilocus sequence typing. C. sakazakii ST4 (10 isolates, 29.4%), ST1 (3 isolates, 8.8%), and ST8 (3 isolates, 8.8%) and C. malonaticus ST7 (four isolates, 11.8%) were dominant. Antibiotic susceptibility testing indicated that all 34 Cronobacter isolates were susceptible to ampicillin-sulbactam, cefotaxime, ciprofloxacin, gentamicin, meropenem, tetracycline, piperacillin-tazobactam, and trimethoprim-sulfamethoxazole, 88.2% were susceptible to chloramphenicol, and 67.6% were resistant to cephalothin. The results of this study enhance knowledge about genotyping and antibiotic resistance of these Cronobacter species and could be used to prevent potential hazards caused by these strains in drinking water and various food products.

  18. Variability in Cell Response of Cronobacter sakazakii after Mild-Heat Treatments and Its Impact on Food Safety

    PubMed Central

    Parra-Flores, Julio; Juneja, Vijay; Garcia de Fernando, Gonzalo; Aguirre, Juan

    2016-01-01

    Cronobacter spp. have been responsible for severe infections in infants associated with consumption of powdered infant formula and follow-up formulae. Despite several risk assessments described in published studies, few approaches have considered the tremendous variability in cell response that small micropopulations or single cells can have in infant formula during storage, preparation or post process/preparation before the feeding of infants. Stochastic approaches can better describe microbial single cell response than deterministic models as we prove in this study. A large variability of lag phase was observed in single cell and micropopulations of ≤50 cells. This variability increased as the heat shock increased and growth temperature decreased. Obviously, variability of growth of individual Cronobacter sakazakii cell is affected by inoculum size, growth temperature and the probability of cells able to grow at the conditions imposed by the experimental conditions should be taken into account, especially when errors in bottle-preparation practices, such as improper holding temperatures, or manipulation, may lead to growth of the pathogen to a critical cell level. The mean probability of illness from initial inoculum size of 1 cell was below 0.2 in all the cases and for inoculum size of 50 cells the mean probability of illness, in most of the cases, was above 0.7. PMID:27148223

  19. My 40-Year History with Cronobacter/Enterobacter sakazakii – Lessons Learned, Myths Debunked, and Recommendations

    PubMed Central

    Farmer, John J.

    2015-01-01

    Much has been learned about organism in the Cronobacter/Enterobacter sakazakii complex since I first named and described Enterobacter sakazakii in 1980. However, there are still wide knowledge gaps. One of the most serious is that are still many uncertainties associated with assessing the public health risk posed by these bacteria, particularly in neonatal meningitis. Over the last few decades, Cronobacter contamination of commercial powdered infant formula products has apparently been reduced, but it is still an ongoing problem. The powdered infant formula industry still cannot produce powdered formula that is free of bacterial contamination with Cronobacter, other Enterobacteriaceae, other pathogenic bacteria, and other microorganisms. Until this happens, infants and other will be at risk of becoming infected when they ingest contaminated formula. PMID:26640778

  20. Investigating the biocontrol and anti-biofilm potential of a three phage cocktail against Cronobacter sakazakii in different brands of infant formula.

    PubMed

    Endersen, Lorraine; Buttimer, Colin; Nevin, Eoghan; Coffey, Aidan; Neve, Horst; Oliveira, Hugo; Lavigne, Rob; O'Mahony, Jim

    2017-07-17

    In recent years, the microbiological safety of powdered infant formula has gained increasing attention due to the identification of contaminating C. sakazakii and its epidemiological link with life-threatening neonatal infections. Current intervention strategies have fallen short of ensuring the production of infant formula that is free from C. sakazakii. In this study, we describe the isolation and characterisation of three bacteriophages (phages) and their application as a phage cocktail to inhibit the growth of C. sakazakii in different brands of infant formula, while also assessing the phages ability to prevent biofilm formation. All three phages, isolated from slurry, possess a relatively broad host range, verified by their ability to infect across genera and species. When all three phages were combined and used as part of a phage cocktail, 73% coverage was obtained across all Cronobacter strains tested. Optimum thermo-tolerance and pH stability were determined between 4°C-37°C, and pH6-8, respectively, well within the normal range of application of infant formula. Genome sequencing and analysis revealed all the phages to be free from lysogenic properties, a trait which renders each favourable for phage therapy applications. As such, the combined-phage preparation (3×10 8 pfu/mL) was found to possess a strong bactericidal effect on C. sakazakii/C. sakazakii LUX cells (≤10 4 cfu/mL), resulting in a significant reduction in cell numbers, to below the limit of detection (<10cfu/mL). This was observed following a 20h challenge in different brands of infant formula, where samples in the absence of the phage cocktail reached concentrations of ~10 9 cfu/mL. The phage cocktail also demonstrated promise in preventing the establishment of biofilm, as biofilm formation could not be detected for up to 48h post treatment. These results highlight the potential application of this phage preparation for biocontrol of C. sakazakii contamination in reconstituted infant

  1. Genetic Diversity, Antimicrobial Susceptibility, and Biofilm Formation of Cronobacter spp. Recovered from Spices and Cereals

    PubMed Central

    Li, Yuanhong; Yu, Huan; Jiang, Hua; Jiao, Yang; Zhang, Yaodong; Shao, Jihong

    2017-01-01

    Cronobacter species are important food-borne opportunistic pathogens which have been implicated in the cause of necrotizing enterocolitis, sepsis, and meningitis in neonates and infants. However, these bacteria are routinely found in foodstuffs, clinical specimens, and environmental samples. This study investigated the genetic diversity, antimicrobial susceptibility, and biofilm formation of Cronobacter isolates (n = 40) recovered from spices and cereals in China during 2014–2015. Based on the fusA sequencing analysis, we found that the majority (23/40, 57.5%) of Cronobacter isolates in spices and cereals were C. sakazakii, while the remaining strains were C. dublinensis (6/40, 15.0%), C. malonaticus (5/40, 12.5%), C. turicensis (4/40, 10.0%), and C. universalis (2/40, 5.0%). Multilocus sequence typing (MLST) analysis produced 30 sequence types (STs) among the 40 Cronobacter isolates, with 5 STs (ST4, ST13, ST50, ST129, and ST158) related to neonatal meningitis. The pattern of the overall ST distribution was diverse; in particular, it was revealed that ST148 was the predominant ST, presenting 12.5% within the whole population. MLST assigned 12 isolates to 7 different clonal complexes (CCs), 4, 13, 16, 17, 72, 129, and 143, respectively. The results of O-antigen serotyping indicated that C. sakazakii serotype O1 and O2 were the most two prevalent serotypes. The antimicrobial susceptibility testing showed that the 40 Cronobacter isolates were susceptible to most of the antibiotics tested except for ceftriaxone, meropenem, and aztreona. Of the 40 Cronobacter strains tested, 13 (32.5%) were assessed as weak bioflim producers, one (2.5%) was a moderate biofilm producer, one (2.5%) was strong biofilm producer, and the others (62.5%) were non-biofilm producers. MLST and O-antigen serotyping have indicated that Cronobacter strains recovered from spices and cereals were genetically diverse. Isolates of clinical origin, particularly the C. sakazakii ST4 neonatal meningitic

  2. Reconstituting the Evolutionary History of Cronobacter Driven by Differentiated CRISPR Activity.

    PubMed

    Zeng, Haiyan; Zhang, Jumei; Wu, Qingping; He, Wenjing; Wu, Haoming; Ye, Yingwang; Li, Chengsi; Ling, Na; Chen, Moutong; Wang, Juan; Cai, Shuzhen; Lei, Tao; Ding, Yu; Xue, Liang

    2018-03-09

    Cronobacter strains harboring the CRISPR-Cas system are important foodborne pathogens causing serious neonatal infections. However, the specific role of the CRISPR-Cas system in bacterial evolution remains relatively unexplored. In this study, we investigated the impact of CRISPR-Cas in Cronobacter evolution and obtained 137 new whole-genome sequences of Cronobacter by next-generation sequencing technology. Among the strains examined (n=240), 90.6% (193/213) of prevalent species Cronobacter sakazakii , Cronobacter malonaticus , and Cronobacter dublinensis strains had intact CRISPR-Cas systems. Two rare species, Cronobacter condimenti (n=2) and Cronobacter universalis (n=6), lacked and preserved the CRISPR-Cas system at a low frequency (1/6), respectively. These results suggest that the presence of one CRISPR-Cas system in Cronobacter is important for the species to maintain genome homeostasis for survival. The Cronobacter ancestral strain was likely to harbored both subtype I-E and I-F CRISPR-Cas systems, during the long evolutionary process, subtype I-E was retained, while subtype I-F selectively degenerated in Cronobacter species and was even lost in the major Cronobacter pathovars. Moreover, significantly higher CRISPR activity was observed in plant-associated species C. dublinensis than in the virulence-related species C. sakazakii and C. malonaticus Similar spacers of CRISPR arrays were rarely found among species, suggesting intensive change through adaptive acquisition and loss. Differentiated CRISPR activity appears to be the product of environmental selective pressure and might contribute to the bidirectional divergence and speciation of Cronobacter IMPORTANCE This study reports the evolutionary history of Cronobacter under the selective pressure of the CRISPR-Cas system. One CRISPR-Cas system in Cronobacter is important for maintaining genome homeostasis, whereas two types of systems may be redundant and not conducive for acquiring beneficial DNA for

  3. Survival and growth of Cronobacter sakazakii on fresh-cut fruit and the effect of UV-C illumination and electrolyzed water in the reduction of its population.

    PubMed

    Santo, David; Graça, Ana; Nunes, Carla; Quintas, Célia

    2016-08-16

    Cronobacter sakazakii, found in foods such as powdered infant formula and plant origin ready-to-eat food, is an opportunistic pathogen to infants, neonates and vulnerable adults. The objective of this study was to monitor the growth of C. sakazakii in fresh-cut 'Royal gala' apple, 'Rocha' pear, and 'Piel de sapo' melon, and the effect of UV-C illumination, acidic electrolyzed water (AEW) and neutral electrolyzed water (NEW) in the reduction of its population. Fresh-cut fruits were inoculated and incubated at different temperatures during 10days while monitoring C. sakazakii. The inhibitory activity of different doses of UV-C (0-10kJ.m(2)), electrolyzed water and sodium hypochlorite (SH) (100ppm chlorine) was evaluated on the fruits inoculated with C. sakazakii. The bacterium showed a significant growth in the fruits at 12 and 20°C, but did not grow at 4°C, despite having survived for 10days. At 8°C, adaptation phases of 0.6-3.9days were estimated in the fruits before exponential growth. The UV-C 7.5 and 10kJ/m(2) produced greater C. sakazakii population decreases (2-2.4logcfu/g) than AEW (1.3-1.8logcfu/g), NEW (1-1.2logcfu/g) and SH (0.8-1.4logcfu/g). The UV-C decontamination system and refrigeration at 4°C, may contribute to the product's safety and quality. The results help better understand the behavior of C. sakazakii on fresh-cut fruit alerting producers of the necessity to respect the high hygienic practices, adequate refrigerating temperature maintenance and caution with the tendency to prolong the validity of this kind of ready-to-eat food. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Ingested Salmonella enterica, Cronobacter sakazakii, Escherichia coli O157:H7, and Listeria monocytogenes: transmission dynamics from adult house flies to their eggs and first filial (F1) generation adults.

    PubMed

    Pava-Ripoll, Monica; Pearson, Rachel E Goeriz; Miller, Amy K; Tall, Ben D; Keys, Christine E; Ziobro, George C

    2015-07-31

    The mechanical transmission of pathogenic bacteria by synanthropic filth flies is widely recognized. While many studies report the fate and the temporospatial distribution of ingested foodborne bacteria by filth flies, there is little evidence about the transmission dynamics of ingested foodborne bacteria by adult house flies (Musca domestica) to their progeny. In this study, we fed parental house fly adults with food contaminated with low, medium, and high concentrations of Salmonella enterica, Cronobacter sakazakii, Escherichia coli O157:H7, and Listeria monocytogenes and evaluated the probability of transmission of these pathogens to house fly eggs and the surface and the alimentary canal of their first filial (F1) generation adults. All foodborne pathogens were present in samples containing pooled house fly eggs. The probability of transmission was higher after parental house flies ingested food containing medium bacterial loads. Cronobacter sakazakii was 16, 6, and 3 times more likely to be transmitted to house fly eggs than S. enterica, E. coli O157:H7, and L. monocytogenes, respectively. Only S. enterica and C. sakazakii were transmitted to F1 generation adults and their presence was 2.4 times more likely on their body surfaces than in their alimentary canals. The highest probabilities of finding S. enterica (60 %) and C. sakazakii (28 %) on newly emerged F1 adults were observed after parental house flies ingested food containing medium and high levels of these pathogens, respectively. Our study demonstrates that adult house flies that fed from food contaminated with various levels of foodborne bacteria were able to transmit those pathogens to their eggs and some were further transmitted to newly emerged F1 generation adults, enhancing the vector potential of these insects. Understanding the type of associations that synanthropic filth flies establish with foodborne pathogens will help to elucidate transmission mechanisms and possible ways to mitigate the

  5. Escherichia coli and Cronobacter sakazakii in 'Tommy Atkins' minimally processed mangos: Survival, growth and effect of UV-C and electrolyzed water.

    PubMed

    Santo, David; Graça, Ana; Nunes, Carla; Quintas, Célia

    2018-04-01

    These studies were aimed at assessing the growing capacity of Escherichia coli and Cronobacter sakazakii and the effectiveness of Ultraviolet-C (UV-C) radiation, acidic electrolyzed (AEW) and neutral electrolyzed (NEW) waters in the inhibition of these bacteria on minimally processed 'Tommy Atkins' mangoes (MPM). The fruits were contaminated by dip inoculation and kept 10 days at 4, 8, 12 and 20 °C while enumerating bacteria. Contaminated mangoes were disinfected using UV-C (2.5, 5, 7.5 and 10 kJ/m 2 ), AEW, NEW and sodium hypochlorite (SH) and the microorganisms were monitored. None of the enterobacteria grew at 4, 8 and 12 °C regardless of having persisted during the 10-day period. At 20 °C, E. coli and C. sakazakii grew, after adaption phases of 48 h and 24 h, to values of 8.7 and 8.5 log cfu/g at day eight, respectively. E. coli showed the highest reduction counts on the MPM washed with NEW and SH (2.2 log cfu/g). UV-C was more effective in reducing C. sakazakii (2.4-2.6 log cfu/g), when compared to AEW, NEW and SH (1.2-1.8 log cfu/g). The efficacy of decontamination technologies depends on microorganisms, highlighting the importance of preventing contamination at the primary production and of combining different methods to increase the safety of fresh-cut fruits. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Comparison of desiccation tolerance among Listeria monocytogenes, Escherichia coli O157:H7, Salmonella enterica, and Cronobacter sakazakii in powdered infant formula.

    PubMed

    Koseki, Shigenobu; Nakamura, Nobutaka; Shiina, Takeo

    2015-01-01

    Bacterial pathogens such as Listeria monocytogenes, Escherichia coli O157:H7, Salmonella enterica, and Cronobacter sakazakii have demonstrated long-term survival in/on dry or low-water activity (aw) foods. However, there have been few comparative studies on the desiccation tolerance among these bacterial pathogens separately in a same food matrix. In the present study, the survival kinetics of the four bacterial pathogens separately inoculated onto powdered infant formula as a model low-aw food was compared during storage at 5, 22, and 35°C. No significant differences in the survival kinetics between E. coli O157:H7 and L. monocytogenes were observed. Salmonella showed significantly higher desiccation tolerance than these pathogens, and C. sakazakii demonstrated significantly higher desiccation tolerance than all other three bacteria studied. Thus, the desiccation tolerance was represented as C. sakazakii > Salmonella > E. coli O157:H7 = L. monocytogenes. The survival kinetics of each bacterium was mathematically analyzed, and the observed kinetics was successfully described using the Weibull model. To evaluate the variability of the inactivation kinetics of the tested bacterial pathogens, the Monte Carlo simulation was performed using assumed probability distribution of the estimated fitted parameters. The simulation results showed that the storage temperature significantly influenced survival of each bacterium under the dry environment, where the bacterial inactivation became faster with increasing storage temperature. Furthermore, the fitted rate and shape parameters of the Weibull model were successfully modelled as a function of temperature. The numerical simulation of the bacterial inactivation was realized using the functions of the parameters under arbitrary fluctuating temperature conditions.

  7. In Silico identification of pathogenic strains of Cronobacter from Biochemical data reveals association of inositol fermentation with pathogenicity.

    PubMed

    Hamby, Stephen E; Joseph, Susan; Forsythe, Stephen J; Chuzhanova, Nadia

    2011-09-20

    Cronobacter, formerly known as Enterobacter sakazakii, is a food-borne pathogen known to cause neonatal meningitis, septicaemia and death. Current diagnostic tests for identification of Cronobacter do not differentiate between species, necessitating time consuming 16S rDNA gene sequencing or multilocus sequence typing (MLST). The organism is ubiquitous, being found in the environment and in a wide range of foods, although there is variation in pathogenicity between Cronobacter isolates and between species. Therefore to be able to differentiate between the pathogenic and non-pathogenic strains is of interest to the food industry and regulators. Here we report the use of Expectation Maximization clustering to categorise 98 strains of Cronobacter as pathogenic or non-pathogenic based on biochemical test results from standard diagnostic test kits. Pathogenicity of a strain was postulated on the basis of either pathogenic symptoms associated with strain source or corresponding MLST sequence types, allowing the clusters to be labelled as containing either pathogenic or non-pathogenic strains. The resulting clusters gave good differentiation of strains into pathogenic and non-pathogenic groups, corresponding well to isolate source and MLST sequence type. The results also revealed a potential association between pathogenicity and inositol fermentation. An investigation of the genomes of Cronobacter sakazakii and C. turicensis revealed the gene for inositol monophosphatase is associated with putative virulence factors in pathogenic strains of Cronobacter. We demonstrated a computational approach allowing existing diagnostic kits to be used to identify pathogenic strains of Cronobacter. The resulting clusters correlated well with MLST sequence types and revealed new information about the pathogenicity of Cronobacter species.

  8. Identification of Natural Animicrobial Substances in Red Muscadine Juice against Cranonbacter sakazakii

    USDA-ARS?s Scientific Manuscript database

    Muscadine grape (Vitis rotundifolia Michx.) juice with natural organic, phenolic acids and polyphenol compounds identified in red muscadine juice (‘Noble’) were tested against Cronobacter sakazakii. Commercial baby juices with high polyphenol content (176.7~347.7 mg/mL), showed poor antimicrobial a...

  9. Identification of Natural Antimicrobial Substances in Red Muscadine Juice against Enterobacter sakazakii

    USDA-ARS?s Scientific Manuscript database

    Red muscadine (Vitis rotundifolia Michx.) juices with natural organic, phenolic acids and polyphenol compounds were tested against Cronobacter sakazakii. The concentration of total phenolic compounds of commercial baby juices ranged from 176.7 to 347.7 mg/mL. Commercial baby juices showed poor antim...

  10. Occurrence and Characterization of Cronobacter spp. in Dehydrated Rice Powder from Chinese Supermarket

    PubMed Central

    Huang, Yan; Pang, Yiheng; Wang, Hong; Tang, Zhengzhu; Zhou, Yan; Zhang, Weiyu; Li, Xiugui; Tan, Dongmei; Li, Jian; Lin, Ying; Liu, Xiaoling; Huang, Weiyi; Shi, Yunliang

    2015-01-01

    Cronobacter spp. are emerging food-borne pathogens and have been identified as causative agents of meningitis and necrotizing enterocolitis in infants. Dehydrated rice is popular with a wide range of people and it is frequently used as a substitute for infant milk powder to baby older than four months. The occurrence of Cronobacter spp. was investigated in 1,012 samples of dehydrated rice powder collected from 14 manufacturers in China during 2010 to 2012. The isolates were identified using fusA allele sequencing and subtyped using pulsed-field gel electrophoresis. Seventy-six samples (7.5%) contained Cronobacter spp. The prevalence among manufacturers ranged from 0-28.8%. The 76 isolates included 4 species [Cronobacter sakazakii (52 isolates) Cronobacter malonaticus (14 isolates), Cronobacter dublinensis (7 isolates), and Cronobacter muytjensii (3 isolates)]. Twenty-three unique fusA alleles and sixty-six PFGE-patterns were detected. All isolated strains were observed to be sensitive or to show intermediate susceptibility to eight tested antimicrobial agents. The study revealed serious contamination of dehydrated rice powder by Cronobacter spp., with prevalence varying among manufacturers in China. Identified Cronobacter species, fusA alleles, and subtypes were diverse. PMID:26132635

  11. Immunogold Nanoparticles for Rapid Plasmonic Detection of C. sakazakii.

    PubMed

    Aly, Mohamed A; Domig, Konrad J; Kneifel, Wolfgang; Reimhult, Erik

    2018-06-25

    Cronobacter sakazakii is a foodborne pathogen that can cause a rare, septicemia, life-threatening meningitis, and necrotizing enterocolitis in infants. In general, standard methods for pathogen detection rely on culture, plating, colony counting and polymerase chain reaction DNA-sequencing for identification, which are time, equipment and skill demanding. Recently, nanoparticle- and surface-based immunoassays have increasingly been explored for pathogen detection. We investigate the functionalization of gold nanoparticles optimized for irreversible and specific binding to C. sakazakii and their use for spectroscopic detection of the pathogen. We demonstrate how 40-nm gold nanoparticles grafted with a poly(ethylene glycol) brush and functionalized with polyclonal antibodies raised against C. sakazakii can be used to specifically target C. sakazakii . The strong extinction peak of the Au nanoparticle plasmon polariton resonance in the optical range is used as a label for detection of the pathogens. Individual binding of the nanoparticles to the C. sakazakii surface is also verified by transmission electron microscopy. We show that a high degree of surface functionalization with anti- C. sakazakii optimizes the detection and leads to a detection limit as low as 10 CFU/mL within 2 h using a simple cuvette-based UV-Vis spectrometric readout that has great potential for further optimization.

  12. DNA-Sequence Based Typing of the Cronobacter Genus Using MLST, CRISPR-cas Array and Capsular Profiling

    PubMed Central

    Ogrodzki, Pauline; Forsythe, Stephen J.

    2017-01-01

    The Cronobacter genus is composed of seven species, within which a number of pathovars have been described. The most notable infections by Cronobacter spp. are of infants through the consumption of contaminated infant formula. The description of the genus has greatly improved in recent years through DNA sequencing techniques, and this has led to a robust means of identification. However some species are highly clonal and this limits the ability to discriminate between unrelated strains by some methods of genotyping. This article updates the application of three genotyping methods across the Cronobacter genus. The three genotyping methods were multilocus sequence typing (MLST), capsular profiling of the K-antigen and colanic acid (CA) biosynthesis regions, and CRISPR-cas array profiling. A total of 1654 MLST profiled and 286 whole genome sequenced strains, available by open access at the PubMLST Cronobacter database, were used this analysis. The predominance of C. sakazakii and C. malonaticus in clinical infections was confirmed. The majority of clinical strains being in the C. sakazakii clonal complexes (CC) 1 and 4, sequence types (ST) 8 and 12 and C. malonaticus ST7. The capsular profile K2:CA2, previously proposed as being strongly associated with C. sakazakii and C. malonaticus isolates from severe neonatal infections, was also found in C. turicensis, C. dublinensis and C. universalis. The majority of CRISPR-cas types across the genus was the I-E (Ecoli) type. Some strains of C. dublinensis and C. muytjensii encoded the I-F (Ypseudo) type, and others lacked the cas gene loci. The significance of the expanding profiling will be of benefit to researchers as well as governmental and industrial risk assessors. PMID:29033918

  13. Evaluation and implementation of a membrane filter method for Cronobacter detection in drinking water.

    PubMed

    Liu, Hui; Yang, Yuelian; Cui, Jinghua; Liu, Lanzheng; Liu, Huiyuan; Hu, Guangchun; Shi, Yuwen; Li, Jian

    2013-07-01

    A membrane filter (MF) method was evaluated for its suitability for qualitative and quantitative analyses of Cronobacter spp. in drinking water by pure strains of Cronobacter and non-Cronobacter, and samples spiked with chlorinated Cronobacter sakazakii ATCC 29544. The applicability was verified by the tests: for pure strains, the sensitivity and the specificity were both 100%; for spiked samples, the MF method recovered 82.8 ± 10.4% chlorinated ATCC 29544 cells. The MF method was also applied to screen Cronobacter spp. in drinking water samples from municipal water supplies on premises (MWSP) and small community water supplies on premises (SCWSP). The isolation rate of Cronobacter spp. from SCWSP samples was 31/114, which was significantly higher than that from MWSP samples which was 1/131. Besides, the study confirmed the possibility of using total coliform as an indicator of contamination level of Cronobacter spp. in drinking water, and the acquired correct positive rate was 96%. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  14. Use of enhanced nisin derivatives in combination with food-grade oils or citric acid to control Cronobacter sakazakii and Escherichia coli O157:H7.

    PubMed

    Campion, Alicia; Morrissey, Ruth; Field, Des; Cotter, Paul D; Hill, Colin; Ross, R Paul

    2017-08-01

    Cronobacter sakazakii and Escherichia coli O157:H7 are well known food-borne pathogens that can cause severe disease. The identification of new alternatives to heating to control these pathogens in foods, while reducing the impact on organoleptic properties and nutritional value, is highly desirable. In this study, nisin and its bioengineered variants, nisin V and nisin S29A, are used alone, or in combination with plant essential oils (thymol, carvacrol and trans-cinnamaldehyde) or citric acid, with a view to controlling C. sakazakii and E. coli O157:H7 in laboratory-based assays and model food systems. The use of nisin variants (30 μM) with low concentrations of thymol (0.015%), carvacrol (0.03%) and trans-cinnamaldehyde (0.035%) resulted in extended lag phases of growth compared to those for corresponding nisin A-essential oil combinations. Furthermore, nisin variants (60 μM) used in combination with carvacrol (0.03%) significantly reduced viable counts of E. coli O157:H7 (3-log) and C. sakazakii (4-log) compared to nisin A-carvacrol treatment. Importantly, this increased effectiveness translated into food. More specifically, sub-inhibitory concentrations of nisin variants and carvacrol caused complete inactivation of E. coli O157:H7 in apple juice within 3 h at room temperature compared to that of the equivalent nisin A combination. Furthermore, combinations of commercial Nisaplin and the food additive citric acid reduced C. sakazakii numbers markedly in infant formula within the same 3 h period. These results highlight the potential benefits of combining nisin and variants thereof with carvacrol and/or citric acid for the inhibition of Gram negative food-borne pathogens. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Detection of viable Cronobacter spp. (Enterobacter sakazakii) by one-step RT-PCR in dry aquatic product.

    PubMed

    Ye, Yingwang; Wu, Qingping; Zhang, Jumei; Jiang, He; Hu, Wang

    2012-11-01

    Cronobacter are opportunistic food-borne pathogens associated with meningitis, sepsis, and necrotizing enterocolitis. Little attempt has focused on detection of viable cell of Cronobacter spp. in dry aquatic products, which were frequently used for raw materials of infant foods due to high nutrition. In this paper, one-step reverse transcription polymerase chain reaction (RT-PCR) was developed for detection of viable Cronobacter spp. in dry aquatic products. Specificity test indicated that clearly expected amplicon in size 469 bp was amplified from RNA of Cronobacter, but not from RNA of negative controls and DNA of Cronobacter strains. The sensitivity was 10(4) CFU/mL of Cronobacter strain in artificially fish meal samples and 10(1) CFU/mL of Cronobacter after 10-h enrichment. In a total of 81 dry aquatic products, 9.8%, 8.6%, and 9.8% of samples were found to be positive for Cronobacter by one-step RT-PCR, U.S. Food and Drug Administration method, and Druggan-Forsythe-Iversen medium, respectively. The results clearly indicated that one-step RT-PCR could avoid the interference of residual DNA of Cronobacter in food samples and be used to specifically detect viable Cronobacter spp. for large-scale monitoring of food samples. The use of rapid and specific detection of food borne pathogens in food samples was most of importance for control and precaution of food borne diseases. In this study, one-step RT-PCR was developed for detection of Cronobacter spp. in aquatic products. A comparison of different methods for detection of Cronobacter indicated that the newly developed method could be widely used to specifically detect Cronobacter spp. in food samples. © 2012 Institute of Food Technologists®

  16. Effect of heat shock on the fatty acid and protein profiles of Cronobacter sakazakii BCRC 13988 as well as its growth and survival in the presence of various carbon, nitrogen sources and disinfectants.

    PubMed

    Li, Po-Ting; Hsiao, Wan-Ling; Yu, Roch-Chui; Chou, Cheng-Chun

    2013-12-01

    In the present study, Cronobacter sakazakii, a foodborne pathogen, was first subjected to heat shock at 47 °C for 15 min. Effect of heat shock on the fatty acid and protein profiles, carbon and nitrogen source requirements as well as the susceptibilities of C. sakazakii to Clidox-S, a chlorine-containing disinfectant and Quatricide, a quaternary ammonium compound were investigated. Results revealed that heat shock increased the proportion of myristic acid (14:0), palmitic acid (16:0) and the ratio of saturated fatty acid to unsaturated fatty acid, while reducing the proportion of palmitoleic acid (16:1) and cis-vacceric acid (18:1). In addition, eleven proteins showed enhanced expression, while one protein showed decreased expression in the heat-shocked compared to the non-heat-shocked cells. Non-heat-shocked cells in the medium supplemented with beef extract exhibited the highest maximum population. On the contrary, the highest maximum population of heat-shocked C. sakazakii was noted in the medium having either tryptone or yeast extract as the nitrogen source. Among the various carbon sources examined, the growth of the test organism, regardless of heat shock, was greatest in the medium having glucose as the carbon source. Furthermore, heat shock enhanced the resistance of C. sakazakii to Clidox-S or Quatricide. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Development of a Custom-Designed, Pan Genomic DNA Microarray to Characterize Strain-Level Diversity among Cronobacter spp.

    PubMed Central

    Tall, Ben Davies; Gangiredla, Jayanthi; Gopinath, Gopal R.; Yan, Qiongqiong; Chase, Hannah R.; Lee, Boram; Hwang, Seongeun; Trach, Larisa; Park, Eunbi; Yoo, YeonJoo; Chung, TaeJung; Jackson, Scott A.; Patel, Isha R.; Sathyamoorthy, Venugopal; Pava-Ripoll, Monica; Kotewicz, Michael L.; Carter, Laurenda; Iversen, Carol; Pagotto, Franco; Stephan, Roger; Lehner, Angelika; Fanning, Séamus; Grim, Christopher J.

    2015-01-01

    Cronobacter species cause infections in all age groups; however neonates are at highest risk and remain the most susceptible age group for life-threatening invasive disease. The genus contains seven species:Cronobacter sakazakii, Cronobacter malonaticus, Cronobacter turicensis, Cronobacter muytjensii, Cronobacter dublinensis, Cronobacter universalis, and Cronobacter condimenti. Despite an abundance of published genomes of these species, genomics-based epidemiology of the genus is not well established. The gene content of a diverse group of 126 unique Cronobacter and taxonomically related isolates was determined using a pan genomic-based DNA microarray as a genotyping tool and as a means to identify outbreak isolates for food safety, environmental, and clinical surveillance purposes. The microarray constitutes 19,287 independent genes representing 15 Cronobacter genomes and 18 plasmids and 2,371 virulence factor genes of phylogenetically related Gram-negative bacteria. The Cronobacter microarray was able to distinguish the seven Cronobacter species from one another and from non-Cronobacter species; and within each species, strains grouped into distinct clusters based on their genomic diversity. These results also support the phylogenic divergence of the genus and clearly highlight the genomic diversity among each member of the genus. The current study establishes a powerful platform for further genomics research of this diverse genus, an important prerequisite toward the development of future countermeasures against this foodborne pathogen in the food safety and clinical arenas. PMID:25984509

  18. A new application of a sodium deoxycholate-propidium monoazide-quantitative PCR assay for rapid and sensitive detection of viable Cronobacter sakazakii in powdered infant formula.

    PubMed

    Zhou, Baoqing; Chen, Bolu; Wu, Xin; Li, Fan; Yu, Pei; Aguilar, Zoraida P; Wei, Hua; Xu, Hengyi

    2016-12-01

    A rapid, reliable, and sensitive method for the detection of Cronobacter sakazakii, a common foodborne pathogen that may cause serious neonatal disease, has been developed. In this study, a rapid real-time quantitative PCR (qPCR) assay combined with sodium deoxycholate (SD) and propidium monoazide (PMA) was developed to detect C. sakazakii contamination in powdered infant formula (PIF). This method could eliminate the interference from dead or injured bacteria. Optimization studies indicated that SD and PMA at 0.08% (wt/vol) and 5µg/mL, respectively, were the most appropriate. In addition, qPCR, PMA-qPCR, SD-PMA-qPCR, and plate count assays were used to account for the number of viable bacteria in cell suspensions that were exposed to a 55°C water bath at different length of time. As a result, the viable number by PMA-qPCR showed significantly higher than of the number from SD-PMA-qPCR or plate counts. The number of viable bacteria was consistent between SD-PMA-qPCR and traditional plate counts, which indicated that SD treatment could eliminate the interference from dead or injured cells. Using the optimized parameters, the limit of detection with the SD-PMA-qPCR assay was 3.3×10 2 cfu/mL and 4.4×10 2 cfu/g in pure culture and in spiked PIF, respectively. A similar detection limit of 5.6×10 2 cfu/g was obtained in the presence of the Staphylococcus aureus (10 7 cfu/mL). The combined SD-PMA-qPCR assay holds promise for the rapid detection of viable C. sakazakii in PIF. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  19. Diversity of O Antigens within the Genus Cronobacter: from Disorder to Order

    PubMed Central

    Javůrková, Barbora; Vlach, Jiří; Göselová, Sandra; Karamonová, Ludmila; Ogrodzki, Pauline; Forsythe, Stephen; Fukal, Ladislav

    2015-01-01

    Cronobacter species are Gram-negative opportunistic pathogens that can cause serious infections in neonates. The lipopolysaccharides (LPSs) that form part of the outer membrane of such bacteria are possibly related to the virulence of particular bacterial strains. However, currently there is no clear overview of O-antigen diversity within the various Cronobacter strains and links with virulence. In this study, we tested a total of 82 strains, covering each of the Cronobacter species. The nucleotide variability of the O-antigen gene cluster was determined by restriction fragment length polymorphism (RFLP) analysis. As a result, the 82 strains were distributed into 11 previously published serotypes and 6 new serotypes, each defined by its characteristic restriction profile. These new serotypes were confirmed using genomic analysis of strains available in public databases: GenBank and PubMLST Cronobacter. Laboratory strains were then tested using the current serotype-specific PCR probes. The results show that the current PCR probes did not always correspond to genomic O-antigen gene cluster variation. In addition, we analyzed the LPS phenotype of the reference strains of all distinguishable serotypes. The identified serotypes were compared with data from the literature and the MLST database (www.pubmlst.org/cronobacter/). Based on the findings, we systematically classified a total of 24 serotypes for the Cronobacter genus. Moreover, we evaluated the clinical history of these strains and show that Cronobacter sakazakii O2, O1, and O4, C. turicensis O1, and C. malonaticus O2 serotypes are particularly predominant in clinical cases. PMID:26070668

  20. Analysis and Characterization of Proteins Associated with Outer Membrane Vesicles Secreted by Cronobacter spp.

    PubMed Central

    Kothary, Mahendra H.; Gopinath, Gopal R.; Gangiredla, Jayanthi; Rallabhandi, Prasad V.; Harrison, Lisa M.; Yan, Qiong Q.; Chase, Hannah R.; Lee, Boram; Park, Eunbi; Yoo, YeonJoo; Chung, Taejung; Finkelstein, Samantha B.; Negrete, Flavia J.; Patel, Isha R.; Carter, Laurenda; Sathyamoorthy, Venugopal; Fanning, Séamus; Tall, Ben D.

    2017-01-01

    Little is known about secretion of outer membrane vesicles (OMVs) by Cronobacter. In this study, OMVs isolated from Cronobacter sakazakii, Cronobacter turicensis, and Cronobacter malonaticus were examined by electron microscopy (EM) and their associated outer membrane proteins (OMP) and genes were analyzed by SDS-PAGE, protein sequencing, BLAST, PCR, and DNA microarray. EM of stained cells revealed that the OMVs are secreted as pleomorphic micro-vesicles which cascade from the cell's surface. SDS-PAGE analysis identified protein bands with molecular weights of 18 kDa to >100 kDa which had homologies to OMPs such as GroEL; OmpA, C, E, F, and X; MipA proteins; conjugative plasmid transfer protein; and an outer membrane auto-transporter protein (OMATP). PCR analyses showed that most of the OMP genes were present in all seven Cronobacter species while a few genes (OMATP gene, groEL, ompC, mipA, ctp, and ompX) were absent in some phylogenetically-related species. Microarray analysis demonstrated sequence divergence among the OMP genes that was not captured by PCR. These results support previous findings that OmpA and OmpX may be involved in virulence of Cronobacter, and are packaged within secreted OMVs. These results also suggest that other OMV-packaged OMPs may be involved in roles such as stress response, cell wall and plasmid maintenance, and extracellular transport. PMID:28232819

  1. Strategies for the Identification and Tracking of Cronobacter Species: An Opportunistic Pathogen of Concern to Neonatal Health

    PubMed Central

    Yan, Qiongqiong; Fanning, Séamus

    2015-01-01

    Cronobacter species are emerging opportunistic food-borne pathogens, which consists of seven species, including C. sakazakii, C. malonaticus, C. muytjensii, C. turicensis, C. dublinensis, C. universalis, and C. condimenti. The organism can cause severe clinical infections, including necrotizing enterocolitis, septicemia, and meningitis, predominately among neonates <4 weeks of age. Cronobacter species can be isolated from various foods and their surrounding environments; however, powdered infant formula (PIF) is the most frequently implicated food source linked with Cronobacter infection. This review aims to provide a summary of laboratory-based strategies that can be used to identify and trace Cronobacter species. The identification of Cronobacter species using conventional culture method and immuno-based detection protocols were first presented. The molecular detection and identification at genus-, and species-level along with molecular-based serogroup approaches are also described, followed by the molecular sub-typing methods, in particular pulsed-field gel electrophoresis and multi-locus sequence typing. Next generation sequence approaches, including whole genome sequencing, DNA microarray, and high-throughput whole-transcriptome sequencing, are also highlighted. Appropriate application of these strategies would contribute to reduce the risk of Cronobacter contamination in PIF and production environments, thereby improving food safety and protecting public health. PMID:26000266

  2. Detection and frequency of Cronobacter spp. (Enterobacter sakazakii) in different categories of ready-to-eat foods other than infant formula.

    PubMed

    Baumgartner, Andreas; Grand, Marius; Liniger, Marianne; Iversen, Carol

    2009-12-31

    Two hundred sixty eight samples of ready-to-eat foods from retail shops were screened for the presence of Cronobacter by selective enrichment followed by plating on three chromogenic agars (ESIA, ESPM and DFI). Cronobacter was isolated from 14/23 samples of sprouts and fresh herbs/salads (60.9%), 7/26 samples of spices and dried herbs (26.9%) and 3/42 confectionery samples (7.1%). In cases where repeat samples were available, foods positive for Cronobacter were retested twice. In total, 54 Cronobacter isolates from 24 foods were recovered and genetic fingerprint patterns generated using PFGE. Identical PFGE-profiles were generated for Cronobacter isolates from five samples of two confectionery products obtained from a particular bakery shop over a period of 11 months. This may indicate a persistent contamination of the production site. For all other isolates, no clustering by phylogenetic analysis of PFGE-profiles was observed, indicating the sporadic nature of Cronobacter in ready-to-eat foods. Enterobacterial counts varied from a maximum value of 2.9 x 10(7) CFU/g (in dill) to a minimum value of <10 CFU/g (in confectionery and dried herbs/spices). There was no correlation between Enterobacterial count and the presence of Cronobacter. Cronobacter may be regularly imported into private households via ready-to-eat foods.

  3. Microbiological quality of selected ready-to-eat leaf vegetables, sprouts and non-pasteurized fresh fruit-vegetable juices including the presence of Cronobacter spp.

    PubMed

    Berthold-Pluta, Anna; Garbowska, Monika; Stefańska, Ilona; Pluta, Antoni

    2017-08-01

    Bacteria of the genus Cronobacter are emerging food-borne pathogens. Foods contaminated with Cronobacter spp. may pose a risk to infants or adults with suppressed immunity. This study was aimed at determining the microbiological quality of ready-to-eat (RTE) plant-origin food products available on the Polish market with special emphasis on the prevalence of Cronobacter genus bacteria. Analyses were carried out on 60 samples of commercial RTE type plant-origin food products, including: leaf vegetables (20 samples), sprouts (20 samples) and non-pasteurized vegetable, fruit and fruit-vegetable juices (20 samples). All samples were determined for the total count of aerobic mesophilic bacteria (TAMB) and for the presence of Cronobacter spp. The isolates of Cronobacter spp. were subjected to genetic identification and differentiation by 16S rDNA sequencing, PCR-RFLP analysis and RAPD-PCR and evaluation of antibiotic susceptibility by the disk diffusion assay. The TAMB count in samples of lettuces, sprouts and non-pasteurized fruit, vegetable and fruit-vegetable juices was in the range of 5.6-7.6, 6.7-8.4 and 2.9-7.7 log CFU g -1 , respectively. The presence of Cronobacter spp. was detected in 21 (35%) samples of the products, including in 6 (30%) samples of leaf vegetables (rucola, lamb's lettuce, endive escarola and leaf vegetables mix) and in 15 (75%) samples of sprouts (alfalfa, broccoli, small radish, lentil, sunflower, leek and sprout mix). No presence of Cronobacter spp. was detected in the analyzed samples of non-pasteurized fruit, vegetable and fruit-vegetable juices. The 21 strains of Cronobacter spp. isolated from leaf vegetable and sprouts included: 13 strains of C. sakazakii, 4 strains of C. muytjensii, 2 strains of C. turicensis, one strain of C. malonaticus and one strain of C. condimenti. All isolated C. sakazakii, C. muytjensii, C. turicensis and C. malonaticus strains were sensitive to ampicillin, cefepime, chloramphenicol, gentamycin

  4. Investigating the Responses of Cronobacter sakazakii to Garlic-Drived Organosulfur Compounds: a Systematic Study of Pathogenic-Bacterium Injury by Use of High-Throughput Whole-Transcriptome Sequencing and Confocal Micro-Raman Spectroscopy

    PubMed Central

    Feng, Shaolong; Eucker, Tyson P.; Holly, Mayumi K.; Konkel, Michael E.

    2014-01-01

    We present the results of a study using high-throughput whole-transcriptome sequencing (RNA-seq) and vibrational spectroscopy to characterize and fingerprint pathogenic-bacterium injury under conditions of unfavorable stress. Two garlic-derived organosulfur compounds were found to be highly effective antimicrobial compounds against Cronobacter sakazakii, a leading pathogen associated with invasive infection of infants and causing meningitis, necrotizing entercolitis, and bacteremia. RNA-seq shows changes in gene expression patterns and transcriptomic response, while confocal micro-Raman spectroscopy characterizes macromolecular changes in the bacterial cell resulting from this chemical stress. RNA-seq analyses showed that the bacterial response to ajoene differed from the response to diallyl sulfide. Specifically, ajoene caused downregulation of motility-related genes, while diallyl sulfide treatment caused an increased expression of cell wall synthesis genes. Confocal micro-Raman spectroscopy revealed that the two compounds appear to have the same phase I antimicrobial mechanism of binding to thiol-containing proteins/enzymes in bacterial cells generating a disulfide stretching band but different phase II antimicrobial mechanisms, showing alterations in the secondary structures of proteins in two different ways. Diallyl sulfide primarily altered the α-helix and β-sheet, as reflected in changes in amide I, while ajoene altered the structures containing phenylalanine and tyrosine. Bayesian probability analysis validated the ability of principal component analysis to differentiate treated and control C. sakazakii cells. Scanning electron microscopy confirmed cell injury, showing significant morphological variations in cells following treatments by these two compounds. Findings from this study aid in the development of effective intervention strategies to reduce the risk of C. sakazakii contamination in the food production environment and on food contact surfaces

  5. The Survey of Cronobacter spp. (formerly Enterbacter sakazakii) in Infant and Follow-up Powdered Formula in China in 2012.

    PubMed

    Pei, Xiao Yan; Yan, Lin; Zhu, Jiang Hui; Li, Ning; Guo, Yun Chang; Fu, Ping; Jia, Hua Yun; Zhang, Xiu Li; Yang, Xiao Rong; Yang, Da Jin

    2016-02-01

    To determine Cronobacter spp. contamination in infant and follow-up powdered formula in China. All of 2282 samples were collected from the retail markets in China from January 2012 to December 2012, and analyzed for Cronobacter spp. by the Chinese National Food Safety Standard. Characterization of the isolates was analyzed by pulsed-field gel electrophoresis (PFGE) with XbaI and SpeI restriction enzymes. Cronobacter spp. strains were isolated from 25 samples, and the positive rates in infant powdered formulas and follow-up powdered formulas were 0.90% (10/1011) and 1.18% (15/1271), respectively. Analysis of variable data regarding different purchasing store formats, seasonality, and production locations as well as comparison of infant versus follow-up formulas did not reveal statistically significant factors. During the sampling period, one of six surveillance zones did exhibit a statistically significant trend towards higher positive rate. PFGE characterization of Cronobacter spp. to elucidate genetic diversity revealed only three pairs of Cronobacter spp. out of 25 having the same PFGE patterns. The current investigation indicated a lower positive rate of Cronobacter spp. in the powdered formula in China. This evidence suggested contamination originating from multiple different sources during the manufacturing process. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  6. Diverse profiles of N-acyl-homoserine lactones in biofilm forming strains of Cronobacter sakazakii.

    PubMed

    Singh, Niharika; Patil, Amrita; Prabhune, Asmita A; Raghav, Mamta; Goel, Gunjan

    2017-04-03

    The present study investigates the role of quorum sensing (QS) molecules expressed by C. sakazakii in biofilm formation and extracellular polysaccharide expression. The QS signaling was detected using Chromobacterium violaceum 026 and Agrobacterium tumefaciens NTL4(pZLR4) based bioassay. Long chain N-acyl-homoserine lactones (AHLs) with C6- C18 chain length were identified using High Performance Liquid Chromatography and Liquid Chromatography-High Resolution Mass Spectrometry. A higher Specific Biofilm Formation (SBF) index (p < 0.05) with the presence of genes associated with cellulose biosynthesis (bcsA, bcsC and bcsG) was observed in the strains. AHLs and their mechanisms can serve as novel targets for developing technologies to eradicate and prevent biofilm formation by C. sakazakii.

  7. Isolation, molecular and phenotypic characterization of Cronobacter spp. in ready-to-eat salads and foods from Japanese cuisine commercialized in Brazil.

    PubMed

    Vasconcellos, Luiza; Carvalho, Carla Trece; Tavares, Rodrigo Overas; de Mello Medeiros, Valéria; de Oliveira Rosas, Carla; Silva, Júlia Nunes; Dos Reis Lopes, Silvia Maria; Forsythe, Stephen James; Brandão, Marcelo Luiz Lima

    2018-05-01

    The aim of this study was to detect Cronobacter from 30 samples of ready-to-eat (RTE) salads and 30 foods from Japanese cuisine as commercially available in Brazil. The detection of Cronobacter was as according to the ISO standard 22964:2017. The isolates were phenotypically characterized by Vitek 2.0 and the antibiotic susceptibility profile was determined using the standardized agar disc diffusion method. Molecular characterization was accomplished by real-time PCR targeting dnaG gene, multiplex-PCR targeting cgcA gene, and fusA allele sequencing. Twenty-seven samples (45.0%) contained Cronobacter, 14 (23.3%) samples of foods from Japanese cuisine and 13 (21.7%) samples of RTE salads. Twenty-nine unique Cronobacter isolates were selected from the 27 positive samples and were identified as C. sakazakii (n = 18), C. malonaticus (n = 8), and C. dublinensis (n = 3). A high genetic diversity was observed, with 29 Cronobacter strains being assigned to 11 different fusA alleles, a ratio of 2.6 strains by fusA allele was found. The cgcA multiplex-PCR failed to identify many of the Cronobacter isolates at the species level. Four (13.8%) Cronobacter isolates were resistant to one or more antibiotics tested (n = 12). The presence of Cronobacter in RTE foods could be a potential threat to human health and highlights the need for high levels of hygiene, particularly when preparing food for elderly, immunosuppressed persons or adults with prior underlying pathology. Epidemiological surveillance agencies should be aware of the risk that these RTE foods may represent, for these groups. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Flagella from Five Cronobacter Species Induce Pro-Inflammatory Cytokines in Macrophage Derivatives from Human Monocytes

    PubMed Central

    Cruz-Córdova, Ariadnna; Rocha-Ramírez, Luz M.; Ochoa, Sara A.; Gónzalez-Pedrajo, Bertha; Espinosa, Norma; Eslava, Carlos; Hernández-Chiñas, Ulises; Mendoza-Hernández, Guillermo; Rodríguez-Leviz, Alejandra; Valencia-Mayoral, Pedro; Sadowinski-Pine, Stanislaw; Hernández-Castro, Rigoberto; Estrada-García, Iris; Muñoz-Hernández, Onofre; Rosas, Irma; Xicohtencatl-Cortes, Juan

    2012-01-01

    Cronobacter spp. are opportunistic pathogens linked to lie-threatening infections in neonates and contaminated powdered infant formula that has been epidemiologically associated with these cases. Clinical symptoms of Cronobacter include necrotizing enterocolitis, bacteremia, and meningitis. Flagella from C. sakazakii are involved in biofilm formation and its adhesion to epithelial cells. We investigated the role of flagella from C. sakazakii ST1 and ST4, C. malonaticus, C. muytjensii, C. turicensis and C. dublinensis during the activation of cytokines (IL-8, TNF-α, and IL-10) in macrophage derivatives from human monocytes, which has not been extensively studied. The production and identity of flagella from the five Cronobacter species were visualized and recognized with anti-flagella antibodies by immunogold labeling through transmission electron microscopy. Purified flagella were dissociated into monomers in 12% SDS-PAGE Coomassie blue-stained gels showing a band of ∼28 kDa and, in addition, mass spectrometry revealed the presence of several peptides that correspond to flagellin. Flagella (100 ng) induced the release of IL-8 (3314–6025 pg/ml), TNF-α (39–359 pg/ml), and IL-10 (2–96 pg/ml), in macrophage isolates from human monocytes and similar results were obtained when flagella were dissociated into monomers. Inhibition assays using three dilutions of anti-flagella antibodies (1∶10, 1∶100, and 1∶200) suppressed the secretion of IL-8, TNF-α, and IL-10 between 95–100% using 100 ng of protein. A transfection assay using 293-hTLR5 cells showed IL-8 release of 197 pg/ml and suppression in the secretion of IL-8 when anti-hTLR5-IgA antibodies were used at different concentrations. These observations suggest that flagella and flagellin are involved in an inflammatory response dependent on TLR5 recognition, which could contribute to the pathogenesis of the bacteria. PMID:23284883

  9. Pan-genome analysis of the emerging foodborne pathogen Cronobacter spp. suggests a species-level bidirectional divergence driven by niche adaptation

    PubMed Central

    2013-01-01

    Background Members of the genus Cronobacter are causes of rare but severe illness in neonates and preterm infants following the ingestion of contaminated infant formula. Seven species have been described and two of the species genomes were subsequently published. In this study, we performed comparative genomics on eight strains of Cronobacter, including six that we sequenced (representing six of the seven species) and two previously published, closed genomes. Results We identified and characterized the features associated with the core and pan genome of the genus Cronobacter in an attempt to understand the evolution of these bacteria and the genetic content of each species. We identified 84 genomic regions that are present in two or more Cronobacter genomes, along with 45 unique genomic regions. Many potentially horizontally transferred genes, such as lysogenic prophages, were also identified. Most notable among these were several type six secretion system gene clusters, transposons that carried tellurium, copper and/or silver resistance genes, and a novel integrative conjugative element. Conclusions Cronobacter have diverged into two clusters, one consisting of C. dublinensis and C. muytjensii (Cdub-Cmuy) and the other comprised of C. sakazakii, C. malonaticus, C. universalis, and C. turicensis, (Csak-Cmal-Cuni-Ctur) from the most recent common ancestral species. While several genetic determinants for plant-association and human virulence could be found in the core genome of Cronobacter, the four Cdub-Cmuy clade genomes contained several accessory genomic regions important for survival in a plant-associated environmental niche, while the Csak-Cmal-Cuni-Ctur clade genomes harbored numerous virulence-related genetic traits. PMID:23724777

  10. Maturation and survival of Cronobacter biofilms on silicone, polycarbonate, and stainless steel after UV light and ethanol immersion treatments.

    PubMed

    Jo, Seo-Hee; Baek, Seung-Bum; Ha, Ji-Hyoung; Ha, Sang-Do

    2010-05-01

    Cronobacter sakazakii cells in biofilms formed on silicone, polycarbonate, and stainless steel coupons immersed in reconstituted powdered infant milk formula were treated with ethanol (10 to 70%) and UV light (12 to 2,160 mW.s/cm(2)) as antibacterial treatments. Biofilm maturation curves were determined after immersion at 25 degrees C for up to 144 h. Populations increased after subsequent immersion at 25 degrees C for 24 h in reconstituted powdered infant milk formula to the respective maximum levels of 7.96, 7.91, and 6.99 log CFU per coupon. Populations attached to silicone and polycarbonate surfaces to a greater extent than to stainless steel (P < 0.05). Treatment with 10% ethanol did not cause a significant decrease in the level of C. sakazakii, but treatment with 30, 40, and 50% ethanol reduced the levels to approximately 1.73, 3.02, and 4.17 log CFU per coupon, respectively. C. sakazakii was not detected on any coupon after treatment with 70% ethanol or 2,160 mW.s/cm(2) UV light. A synergistic effect of sequential ethanol and UV treatments was not observed.

  11. Differentiation of Cronobacter spp. by tryptic digestion of the cell suspension followed by MALDI-TOF MS analysis.

    PubMed

    Krásný, Lukáš; Rohlová, Eva; Růžičková, Helena; Santrůček, Jiří; Hynek, Radovan; Hochel, Igor

    2014-03-01

    Intact cell MALDI-TOF mass spectrometry is a rapid tool for the identification and classification of microorganisms, now widely used even in clinical laboratories. However, its distinctive power is not sufficient for some closely-related species. The genus Cronobacter, formerly known as Enterobacter sakazakii, contains such species. In this work, a new method for the differentiation of five Cronobacter species is presented involving the tryptic digestion of cytoplasmatic proteins followed by MALDI mass spectrometry analysis. A database was developed for use in Bruker Biotyper software including 52 reference spectra and tested on a set of 45 samples with an overall accuracy of about 80%. The possibility of measurement automation and the short time and low cost requirements of this method compared to those of biochemical tests or PCR methods make it a supplementary option to intact cell MALDI, providing additional information about the differentiation of problematic species. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Variability in cell response of Cronobacter sakazakii after mild-heat treatments and its impact on food safety

    USDA-ARS?s Scientific Manuscript database

    Cronobacter spp. have been responsible for severe infections in infants associated with consumption of powdered infant formula (PIF) and follow-up formulae (FUF). Despite several risk assessments described in published studies, few approaches have considered the tremendous variability in cell respo...

  13. Insights into the Emergent Bacterial Pathogen Cronobacter spp., Generated by Multilocus Sequence Typing and Analysis

    PubMed Central

    Joseph, Susan; Forsythe, Stephen J.

    2012-01-01

    Cronobacter spp. (previously known as Enterobacter sakazakii) is a bacterial pathogen affecting all age groups, with particularly severe clinical complications in neonates and infants. One recognized route of infection being the consumption of contaminated infant formula. As a recently recognized bacterial pathogen of considerable importance and regulatory control, appropriate detection, and identification schemes are required. The application of multilocus sequence typing (MLST) and analysis (MLSA) of the seven alleles atpD, fusA, glnS, gltB, gyrB, infB, and ppsA (concatenated length 3036 base pairs) has led to considerable advances in our understanding of the genus. This approach is supported by both the reliability of DNA sequencing over subjective phenotyping and the establishment of a MLST database which has open access and is also curated; http://www.pubMLST.org/cronobacter. MLST has been used to describe the diversity of the newly recognized genus, instrumental in the formal recognition of new Cronobacter species (C. universalis and C. condimenti) and revealed the high clonality of strains and the association of clonal complex 4 with neonatal meningitis cases. Clearly the MLST approach has considerable benefits over the use of non-DNA sequence based methods of analysis for newly emergent bacterial pathogens. The application of MLST and MLSA has dramatically enabled us to better understand this opportunistic bacterium which can cause irreparable damage to a newborn baby’s brain, and has contributed to improved control measures to protect neonatal health. PMID:23189075

  14. Cellular Injuries in Cronobacter sakazakii CIP 103183T and Salmonella enterica Exposed to Drying and Subsequent Heat Treatment in Milk Powder.

    PubMed

    Lang, Emilie; Guyot, Stéphane; Peltier, Caroline; Alvarez-Martin, Pablo; Perrier-Cornet, Jean-Marie; Gervais, Patrick

    2018-01-01

    Because of the ability of foodborne pathogens to survive in low-moisture foods, their decontamination is an important issue in food protection. This study aimed to clarify some of the cellular mechanisms involved in inactivation of foodborne pathogens after drying and subsequent heating. Individual strains of Salmonella Typhimurium, Salmonella Senftenberg, and Cronobacter sakazakii were mixed into whole milk powder and dried to different water activity levels (0.25 and 0.58); the number of surviving cells was determined after drying and subsequent thermal treatments in closed vessels at 90 and 100°C, for 30 and 120 s. For each condition, the percentage of unculturable cells was estimated and, in parallel, membrane permeability and respiratory activity were estimated by flow cytometry using fluorescent probes. After drying, it was clearly observable that the percentage of unculturable cells was correlated with the percentage of permeabilized cells (responsible for 20-40% of the total inactivated bacteria after drying), and to a lesser degree with the percentage of cells presenting with loss of respiratory activity. In contrast, the percentages of unculturable cells observed after heat treatment were strongly correlated with the loss of respiratory activity and weakly with membrane permeability (for 70-80% of the total inactivated bacteria after heat treatment). We conclude that cell inactivation during drying is closely linked to membrane permeabilization and that heat treatment of dried cells affects principally their respiratory activity. These results legitimize the use of time-temperature scales and allow better understanding of the cellular mechanisms of bacterial death during drying and subsequent heat treatment. These results may also allow better optimization of the decontamination process to ensure food safety by targeting the most deleterious conditions for bacterial cells without denaturing the food product.

  15. Cellular Injuries in Cronobacter sakazakii CIP 103183T and Salmonella enterica Exposed to Drying and Subsequent Heat Treatment in Milk Powder

    PubMed Central

    Lang, Emilie; Guyot, Stéphane; Peltier, Caroline; Alvarez-Martin, Pablo; Perrier-Cornet, Jean-Marie; Gervais, Patrick

    2018-01-01

    Because of the ability of foodborne pathogens to survive in low-moisture foods, their decontamination is an important issue in food protection. This study aimed to clarify some of the cellular mechanisms involved in inactivation of foodborne pathogens after drying and subsequent heating. Individual strains of Salmonella Typhimurium, Salmonella Senftenberg, and Cronobacter sakazakii were mixed into whole milk powder and dried to different water activity levels (0.25 and 0.58); the number of surviving cells was determined after drying and subsequent thermal treatments in closed vessels at 90 and 100°C, for 30 and 120 s. For each condition, the percentage of unculturable cells was estimated and, in parallel, membrane permeability and respiratory activity were estimated by flow cytometry using fluorescent probes. After drying, it was clearly observable that the percentage of unculturable cells was correlated with the percentage of permeabilized cells (responsible for 20–40% of the total inactivated bacteria after drying), and to a lesser degree with the percentage of cells presenting with loss of respiratory activity. In contrast, the percentages of unculturable cells observed after heat treatment were strongly correlated with the loss of respiratory activity and weakly with membrane permeability (for 70–80% of the total inactivated bacteria after heat treatment). We conclude that cell inactivation during drying is closely linked to membrane permeabilization and that heat treatment of dried cells affects principally their respiratory activity. These results legitimize the use of time–temperature scales and allow better understanding of the cellular mechanisms of bacterial death during drying and subsequent heat treatment. These results may also allow better optimization of the decontamination process to ensure food safety by targeting the most deleterious conditions for bacterial cells without denaturing the food product. PMID:29593704

  16. Comparative Genotypic and Phenotypic Analysis of Cronobacter Species Cultured from Four Powdered Infant Formula Production Facilities: Indication of Pathoadaptation along the Food Chain

    PubMed Central

    Yan, Qiongqiong; Wang, Juan; Gangiredla, Jayanthi; Cao, Yu; Martins, Marta; Gopinath, Gopal R.; Stephan, Roger; Lampel, Keith; Tall, Ben D.

    2015-01-01

    Cronobacter species are opportunistic pathogens commonly found in the environment. Among the seven Cronobacter species, Cronobacter sakazakii sequence type 4 (ST-4) is predominantly associated with recorded cases of infantile meningitis. This study reports on a 26-month powdered infant formula (PIF) surveillance program in four production facilities located in distinct geographic regions. The objective was to identify the ST(s) in PIF production environments and to investigate the phenotypic features that support their survival. Of all 168 Cronobacter isolates, 133 were recovered from a PIF production environment, 31 were of clinical origin, and 4 were laboratory type strains. Sequence type 1 (n = 84 isolates; 63.9%) was the dominant type in PIF production environments. The majority of these isolates clustered with an indistinguishable pulsotype and persisted for at least an 18-month period. Moreover, DNA microarray results identified two phylogenetic lineages among ST-4 strains tested. Thereafter, the ST-1 and -4 isolates were phenotypically compared. Differences were noted based on the phenotypes expressed by these isolates. The ST-1 PIF isolates produced stronger biofilms at both 28°C and 37°C, while the ST-4 clinical isolates exhibited greater swimming activity and increased binding to Congo red dye. Given the fact that PIF is a low-moisture environment and that the clinical environment provides for an interaction between the pathogen and its host, these differences may be consistent with a form of pathoadaptation. These findings help to extend our current understanding of the epidemiology and ecology of Cronobacter species in PIF production environments. PMID:25911470

  17. Microbiological Quality of Raw Dried Pasta from the German Market, with Special Emphasis on Cronobacter Species.

    PubMed

    Akineden, Ömer; Murata, Kristina Johanna; Gross, Madeleine; Usleber, Ewald

    2015-12-01

    The microbiological quality of 132 dried pasta products available on the German market, originating from 11 different countries, was studied. Sample materials included soft or durum wheat products, some of which produced with other ingredients such as eggs, spices, or vegetables. Parameters included hygiene indicators (aerobic plate count, mold count, the presence of Enterobacteriaceae) and pathogenic/toxinogenic bacterial species (Salmonella spp., Staphylococcus aureus, presumptive Bacillus cereus, and Cronobacter spp.). The overall results of hygiene parameters indicated a satisfactory quality. Salmonella was not found in any sample. Three samples were positive for S. aureus (10(2) to 10(4) colony forming unit (CFU)/g). Presumptive B. cereus at levels of 10(3) to 10(4) CFU/g were detected in 3 samples. Cronobacter spp. were isolated from 14 (10.6%) products. Of these, 9 isolates were identified as C. sakazakii, 2 each as C. turicensis and C. malonaticus, and 1 as C. muytjensii. The isolates were assigned to 9 multilocus sequence typing (MLST) sequence types and to 14 different PFGE profiles. Although pasta products are typically cooked before consumption, some consumers, and children in particular, may also eat raw pasta as nibbles. Raw pasta seems to be a relevant source of exposure to dietary Cronobacter spp., although health risks are probably restricted to vulnerable consumers. High numbers of presumptive B. cereus as found in some samples may be a risk after improper storage of cooked pasta products because toxinogenic strains are frequently found within this species. © 2015 Institute of Food Technologists®

  18. Individual cell lag time distributions of Cronobacter (Enterobacter sakazakii) and impact of pooling samples on its detection in powdered infant formula.

    PubMed

    Miled, Rabeb Bennour; Guillier, Laurent; Neves, Sandra; Augustin, Jean-Christophe; Colin, Pierre; Besse, Nathalie Gnanou

    2011-06-01

    Cells of six strains of Cronobacter were subjected to dry stress and stored for 2.5 months at ambient temperature. The individual cell lag time distributions of recovered cells were characterized at 25 °C and 37 °C in non-selective broth. The individual cell lag times were deduced from the times taken by cultures from individual cells to reach an optical density threshold. In parallel, growth curves for each strain at high contamination levels were determined in the same growth conditions. In general, the extreme value type II distribution with a shape parameter fixed to 5 (EVIIb) was the most effective at describing the 12 observed distributions of individual cell lag times. Recently, a model for characterizing individual cell lag time distribution from population growth parameters was developed for other food-borne pathogenic bacteria such as Listeria monocytogenes. We confirmed this model's applicability to Cronobacter by comparing the mean and the standard deviation of individual cell lag times to populational lag times observed with high initial concentration experiments. We also validated the model in realistic conditions by studying growth in powdered infant formula decimally diluted in Buffered Peptone Water, which represents the first enrichment step of the standard detection method for Cronobacter. Individual lag times and the pooling of samples significantly affect detection performances. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Principal component analysis of normalized full spectrum mass spectrometry data in multiMS-toolbox: An effective tool to identify important factors for classification of different metabolic patterns and bacterial strains.

    PubMed

    Cejnar, Pavel; Kuckova, Stepanka; Prochazka, Ales; Karamonova, Ludmila; Svobodova, Barbora

    2018-06-15

    Explorative statistical analysis of mass spectrometry data is still a time-consuming step. We analyzed critical factors for application of principal component analysis (PCA) in mass spectrometry and focused on two whole spectrum based normalization techniques and their application in the analysis of registered peak data and, in comparison, in full spectrum data analysis. We used this technique to identify different metabolic patterns in the bacterial culture of Cronobacter sakazakii, an important foodborne pathogen. Two software utilities, the ms-alone, a python-based utility for mass spectrometry data preprocessing and peak extraction, and the multiMS-toolbox, an R software tool for advanced peak registration and detailed explorative statistical analysis, were implemented. The bacterial culture of Cronobacter sakazakii was cultivated on Enterobacter sakazakii Isolation Agar, Blood Agar Base and Tryptone Soya Agar for 24 h and 48 h and applied by the smear method on an Autoflex speed MALDI-TOF mass spectrometer. For three tested cultivation media only two different metabolic patterns of Cronobacter sakazakii were identified using PCA applied on data normalized by two different normalization techniques. Results from matched peak data and subsequent detailed full spectrum analysis identified only two different metabolic patterns - a cultivation on Enterobacter sakazakii Isolation Agar showed significant differences to the cultivation on the other two tested media. The metabolic patterns for all tested cultivation media also proved the dependence on cultivation time. Both whole spectrum based normalization techniques together with the full spectrum PCA allow identification of important discriminative factors in experiments with several variable condition factors avoiding any problems with improper identification of peaks or emphasis on bellow threshold peak data. The amounts of processed data remain still manageable. Both implemented software utilities are available

  20. Enterobacter sakazakii in food and beverages (other than infant formula and milk powder).

    PubMed

    Friedemann, Miriam

    2007-05-01

    The ubiqitous microorganism Enterobacter sakazakii is a rare contaminant of infant formula and may cause severe systemic infection in neonates. So far, other food is not known to cause E. sakazakii-infections. The scarce information about the ecology of E. sakazakii and the uncertainty concerning the source of infection in children and adults warrant a summary of the current knowledge about the presence of this opportunistic microorganism in food other than infant formula. This review systematizes publications on the presence of E. sakazakii in food and beverages until June 2006. Food other than infant formula has been rarely investigated for the presence of E. sakazakii. Nevertheless, this microorganism could be isolated from a wide spectrum of food and food ingredients. E. sakazakii was isolated from plant food and food ingredients like cereal, fruit and vegetables, legume products, herbs and spices as well as from animal food sources like milk, meat and fish and products made from these foods. The spectrum of E. sakazakii-contaminated food covers both raw and processed food. The kind of processing of E. sakazakii-contaminated food was not restricted to dry products. Fresh, frozen, ready-to-eat, fermented and cooked food products as well as beverages and water suitable for the preparation of food, were found to be contaminated by E. sakazakii. Although E. sakazakii-contaminated food do not have general public health significance, measures for prevention should consider the presence of E. sakazakii in food, food ingredients, their processing and preparation as possible source of contamination, colonization or infection.

  1. Inhibitory effects of bovine lactoferrin and lactoferricin B on Enterobacter sakazakii.

    PubMed

    Wakabayashi, Hiroyuki; Yamauchi, Koji; Takase, Mitsunori

    2008-03-01

    The susceptibility of Enterobacter sakazakii, a food-borne pathogen, to several metal-bound forms of bovine lactoferrin (LF), pepsin-hydrolyzed LF (LF-hyd), and LF-derived peptide lactoferricin B (LFcin B) was tested. MIC and MBC testing revealed that 4 strains of E. sakazakii show susceptibility to apo- and Cu-LF, LF-hyd, and LFcin B, but not to Fe-LF, similarly to Escherichia coli. A growth curve test indicated that E. sakazakii was inhibited in a dose-dependent manner by apo-LF at 0.5 to 8 mg/ml. Even after being heated at 80 degrees C, LF at above 1 mg/ml inhibited the bacterial growth. These results suggest that bovine LF-related compounds may be useful for the inhibition of E. sakazakii in foods.

  2. Complete genome sequence of the thermotolerant foodborne pathogen Salmonella enterica serovar Senftenberg ATCC 43845 and phylogenetic analysis of loci encoding thermotolerance

    USDA-ARS?s Scientific Manuscript database

    Introduction: Previous studies in Cronobacter sakazakii, Klebsiella spp., and Escherichia coli have identified a genomic island that confers thermotolerance to its hosts. This island has recently been identified in Salmonella enterica serovar Senfentenberg ATCC 43845, a historically important, heat ...

  3. Prevalence and Relative Risk of Cronobacter spp., Salmonella spp., and Listeria monocytogenes Associated with the Body Surfaces and Guts of Individual Filth Flies

    PubMed Central

    Pearson, Rachel E. Goeriz; Miller, Amy K.; Ziobro, George C.

    2012-01-01

    Although flies are important vectors of food-borne pathogens, there is little information to accurately assess the food-related health risk of the presence of individual flies, especially in urban areas. This study quantifies the prevalence and the relative risk of food-borne pathogens associated with the body surfaces and guts of individual wild flies. One hundred flies were collected from the dumpsters of 10 randomly selected urban restaurants. Flies were identified using taxonomic keys before being individually dissected. Cronobacter spp., Salmonella spp., and Listeria monocytogenes were detected using the PCR-based BAX system Q7. Positive samples were confirmed by culture on specific media and through PCR amplification and sequencing or ribotyping. Among collected flies were the housefly, Musca domestica (47%), the blowflies, Lucilia cuprina (33%) and Lucilia sericata (14%), and others (6%). Cronobacter species were detected in 14% of flies, including C. sakazakii, C. turicensis, and C. universalis, leading to the proposal of flies as a natural reservoir of this food-borne pathogen. Six percent of flies carried Salmonella enterica, including the serovars Poona, Hadar, Schwarzengrund, Senftenberg, and Brackenridge. L. monocytogenes was detected in 3% of flies. Overall, the prevalence of food-borne pathogens was three times greater in the guts than on the body surfaces of the flies. The relative risk of flies carrying any of the three pathogens was associated with the type of pathogen, the body part of the fly, and the ambient temperature. These data enhance the ability to predict the microbiological risk associated with the presence of individual flies in food and food facilities. PMID:22941079

  4. 42 CFR 423.894 - Construction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Construction. 423.894 Section 423.894 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE... Prescription Drug Plans § 423.894 Construction. Nothing in this part must be interpreted as prohibiting or...

  5. 42 CFR 423.894 - Construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Construction. 423.894 Section 423.894 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE... Plans § 423.894 Construction. Nothing in this part must be interpreted as prohibiting or restricting: (a...

  6. 42 CFR 423.894 - Construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Construction. 423.894 Section 423.894 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE... Plans § 423.894 Construction. Nothing in this part must be interpreted as prohibiting or restricting: (a...

  7. 42 CFR 423.894 - Construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Construction. 423.894 Section 423.894 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE... Prescription Drug Plans § 423.894 Construction. Nothing in this part must be interpreted as prohibiting or...

  8. 42 CFR 423.894 - Construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Construction. 423.894 Section 423.894 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE... Prescription Drug Plans § 423.894 Construction. Nothing in this part must be interpreted as prohibiting or...

  9. Meningoencephalitis and Compartmentalization of the Cerebral Ventricles Caused by Enterobacter sakazakii

    PubMed Central

    Kleiman, Martin B.; Allen, Stephen D.; Neal, Patricia; Reynolds, Janet

    1981-01-01

    A necrotizing meningoencephalitis complicated by ventricular compartmentalization and abscess formation caused by Enterobacter sakazakii in a previously healthy 5-week-old female is described. A detailed description of the isolate is presented. This communication firmly establishes the pathogenicity of E. sakazakii. PMID:7287892

  10. Diversity of Cronobacter spp. isolates from the vegetables in the middle-east coastline of China.

    PubMed

    Chen, Wanyi; Yang, Jielin; You, Chunping; Liu, Zhenmin

    2016-06-01

    Cronobacter spp. has caused life-threatening neonatal infections mainly resulted from consumption of contaminated powdered infant formula. A total of 102 vegetable samples from retail markets were evaluated for the presence of Cronobacter spp. Thirty-five presumptive Cronobacter isolates were isolated and identified using API 20E and 16S rDNA sequencing analyses. All isolates and type strains were characterized using enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR), and genetic profiles of cluster analysis from this molecular typing test clearly showed that there were differences among isolates from different vegetables. A polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) based on the amplification of the gyrB gene (1258 bp) was developed to differentiate among Cronobacter species. A new PCR-RFLP assay based on the amplification of the gyrB gene using Alu I and Hinf I endonuclease combination is established and it has been confirmed an accurate and rapid subtyping method to differentiate Cronobacter species. Sequence analysis of the gyrB gene was proven to be suitable for the phylogenetic analysis of the Cronobacter strains, which has much better resolution based on SNPs in the identification of Cronobacter species specificity than PCR-RFLP and ERIC-PCR. Our study further confirmed that vegetables are one of the most common habitats or sources of Cronobacter spp. contamination in the middle-east coastline of China.

  11. Inactivation of Enterobacter sakazakii of dehydrated infant formula by gamma-irradiation

    NASA Astrophysics Data System (ADS)

    Lee, Ju-Woon; Oh, Sang-Hee; Byun, Eui-Baek; Kim, Jae-Hun; Kim, Jang-Ho; Woon, Jae-Ho; Byun, Myung-Woo

    2007-11-01

    Enterobacter sakazakii has been implicated as a causal organism in a severe form of neonatal meningitis, with reported mortality rates of 20%. The population at greatest risk is immunocompromised infants of any age. Dried infant formula has been identified as a potential source of the organism in both outbreaks and sporadic cases. The objective of this study was to investigate theirradiation effect of the inactivation on E. sakazakii (ATCC 29544) of a dehydrated infant formula. The D10-values were 0.22-0.27 and 0.76 kGy for broth and dehydrated infant formula, respectively. The irradiation at 5.0 kGy was able to completely eliminate the E. sakazakii inoculated at 8.0 to 9.0 log CFU g -1 onto a dehydrated infant formula. There was no regrowth for all samples during the time they were stored at 10 °C for 6 h after rehydration. The present results indicated that a gamma-irradiation could potentially be used to inactivate E. sakazakii in a dehydrated powdered infant formula.

  12. 7 CFR 1951.894 - Debt settlement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Debt settlement. 1951.894 Section 1951.894 Agriculture... REGULATIONS (CONTINUED) SERVICING AND COLLECTIONS Rural Development Loan Servicing § 1951.894 Debt settlement. Debt settlement of all claims will be handled in accordance with the Federal Claims Collection...

  13. 48 CFR 1835.016-70 - Foreign participation under broad agency announcements (BAAs).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... broad agency announcements (BAAs). 1835.016-70 Section 1835.016-70 Federal Acquisition Regulations... DEVELOPMENT CONTRACTING 1835.016-70 Foreign participation under broad agency announcements (BAAs). (a) Policy. (1) NASA seeks the broadest participation in response to broad agency announcements, including...

  14. Inhibitory activity of Paenibacillus polymyxa on the biofilm formation of Cronobacter spp. on stainless steel surfaces.

    PubMed

    Yang, Soonwook; Kim, Seonhwa; Ryu, Jee-Hoon; Kim, Hoikyung

    2013-07-01

    The objective of this study was to control the survival or biofilm formation of Cronobacter spp. on stainless steel surfaces using Paenibacillus polymyxa. The antibacterial activity of a cell-free culture supernatant (CFCS) of P. polymyxa against Cronobacter spp. was found to vary with P. polymyxa incubation time. Maximum activity occurred when P. polymyxa was incubated at 25 or 30 °C for 96 h. When the CFCS was introduced to Cronobacter spp. adhered to stainless steel strips at 25 °C for up to 72 h, the CFCS successfully inhibited Cronobacter biofilm formation. Additionally, stainless steel surfaces with a preformed P. polymyxa biofilm were exposed to Cronobacter spp. suspensions in PBS or 0.1% peptone water at 3, 5, or 7 log CFU/mL to facilitate its attachment. The Cronobacter population significantly decreased on this surface, regardless of inoculum level or carrier, when the P. polymyxa biofilm was present. However, the microbial population decreased within 6 h and remained unchanged thereafter when the surface was immersed in an inoculum suspended in 0.1% peptone water at 5 or 7 log CFU/mL. These results indicate that P. polymyxa is able to use a promising candidate competitive-exclusion microorganism to control Cronobacter spp. © 2013 Institute of Food Technologists®

  15. 48 CFR 1835.016-70 - Foreign participation under broad agency announcements (BAAs).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... under broad agency announcements (BAAs). 1835.016-70 Section 1835.016-70 Federal Acquisition Regulations... DEVELOPMENT CONTRACTING 1835.016-70 Foreign participation under broad agency announcements (BAAs). (a) Policy. (1) NASA seeks the broadest participation in response to broad agency announcements, including...

  16. 48 CFR 1835.016-70 - Foreign participation under broad agency announcements (BAAs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... under broad agency announcements (BAAs). 1835.016-70 Section 1835.016-70 Federal Acquisition Regulations... DEVELOPMENT CONTRACTING 1835.016-70 Foreign participation under broad agency announcements (BAAs). (a) Policy. (1) NASA seeks the broadest participation in response to broad agency announcements, including...

  17. 48 CFR 1835.016-70 - Foreign participation under broad agency announcements (BAAs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... under broad agency announcements (BAAs). 1835.016-70 Section 1835.016-70 Federal Acquisition Regulations... DEVELOPMENT CONTRACTING 1835.016-70 Foreign participation under broad agency announcements (BAAs). (a) Policy. (1) NASA seeks the broadest participation in response to broad agency announcements, including...

  18. 48 CFR 1835.016-70 - Foreign participation under broad agency announcements (BAAs).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... under broad agency announcements (BAAs). 1835.016-70 Section 1835.016-70 Federal Acquisition Regulations... DEVELOPMENT CONTRACTING 1835.016-70 Foreign participation under broad agency announcements (BAAs). (a) Policy. (1) NASA seeks the broadest participation in response to broad agency announcements, including...

  19. Cellulose as an extracellular matrix component present in Enterobacter sakazakii biofilms.

    PubMed

    Grimm, Maya; Stephan, Roger; Iversen, Carol; Manzardo, Giuseppe G G; Rattei, Thomas; Riedel, Kathrin; Ruepp, Andreas; Frishman, Dmitrij; Lehner, Angelika

    2008-01-01

    Cellulose was identified and characterized as an extracellular matrix component present in the biofilm of an Enterobacter sakazakii clinical isolate grown in nutrient-deficient (M9) medium. Using a bacterial artificial cloning approach in Escherichia coli and subsequent screening of transformants for fluorescence on calcofluor plates, nine genes organized in two operons were identified as putatively responsible for the biosynthesis of cellulose. In addition to the genes already described for cellulose production, two more genes were identified, putatively transcribed together with the genes from the first operon. Putative cellulose in E. sakazakii ES5 biofilm grown on glass coverslips was visualized by calcofluor staining and confocal fluorescence laser scanning microscopy. For the first time, the presence of cellulose in biofilms produced by E. sakazakii was confirmed by methylation analysis.

  20. A novel robotic surgical technique for thyroid surgery: bilateral axillary approach (BAA).

    PubMed

    Woo, Jung-Woo; Kim, Seo Ki; Park, Inhye; Choe, Jun Ho; Kim, Jung-Han; Kim, Jee Soo

    2017-02-01

    Bilateral axillo-breast approach (BABA) robotic thyroidectomy (RT) is proven to be a feasible method for the treatment of well-differentiated thyroid cancers in terms of oncology as well as cosmesis. However, BABA RT causes postoperative sternal discomfort and needs an incision over the nipple areolar area. Here, we suggest a novel robotic surgical technique for thyroid surgery that does not need a breast incision-bilateral axillary approach (BAA). We recruited 51 patients who were willing to undergo the novel BAA robotic thyroid surgery. We performed a propensity score-matched analysis to compare the BAA robotic thyroid surgery group (BAA group) with the conventional open thyroid surgery group (open group). Mean operation time in the BAA group (129.7 min) was significantly longer than that in the open group (103.1 min) (p < 0.001). However, no significant differences in the mean number of metastatic lymph nodes (LNs), mean number of retrieved LNs, vocal cord palsy, hypoparathyroidism, and mean stimulated thyroglobulin level were observed between the two groups. There was no case of postoperative bleeding or chyle leak. Of the 51 patients who had undergone the BAA procedure, 27 patients answered the questionnaire. The mean scale, ranging from 0 to 10, at postoperative 1 day/2 weeks was as follows: voice change score, 3.0/1.6; swallowing difficulty score, 4.0/2.0; anterior neck pain score, 4.6/3.6; anterior neck numbness score, 5.4/4.3; right chest pain score, 3.8/2.1; left chest pain score, 3.6/2.3; right chest numbness score, 3.2/2.8; left chest numbness score, 2.4/2.7; right breast pain score, 0.9/0; left breast pain score, 1.2/0; right breast numbness score, 1.7/0; and left breast numbness score, 2.6/0, respectively. BAA robotic thyroid surgery is a novel, safe, and feasible oncoplastic method, especially for patients who have fear of procedures around the nipple areolar complex.

  1. 9 CFR 89.4 - Watering.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Watering. 89.4 Section 89.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS STATEMENT OF POLICY UNDER THE TWENTY-EIGHT HOUR...

  2. Identification of Cronobacter species by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with an optimized analysis method.

    PubMed

    Wang, Qi; Zhao, Xiao-Juan; Wang, Zi-Wei; Liu, Li; Wei, Yong-Xin; Han, Xiao; Zeng, Jing; Liao, Wan-Jin

    2017-08-01

    Rapid and precise identification of Cronobacter species is important for foodborne pathogen detection, however, commercial biochemical methods can only identify Cronobacter strains to genus level in most cases. To evaluate the power of mass spectrometry based on matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF MS) for Cronobacter species identification, 51 Cronobacter strains (eight reference and 43 wild strains) were identified by both MALDI-TOF MS and 16S rRNA gene sequencing. Biotyper RTC provided by Bruker identified all eight reference and 43 wild strains as Cronobacter species, which demonstrated the power of MALDI-TOF MS to identify Cronobacter strains to genus level. However, using the Bruker's database (6903 main spectra products) and Biotyper software, the MALDI-TOF MS analysis could not identify the investigated strains to species level. When MALDI-TOF MS analysis was performed using the combined in-house Cronobacter database and Bruker's database, bin setting, and unweighted pair group method with arithmetic mean (UPGMA) clustering, all the 51 strains were clearly identified into six Cronobacter species and the identification accuracy increased from 60% to 100%. We demonstrated that MALDI-TOF MS was reliable and easy-to-use for Cronobacter species identification and highlighted the importance of establishing a reliable database and improving the current data analysis methods by integrating the bin setting and UPGMA clustering. Copyright © 2017. Published by Elsevier B.V.

  3. Occurrence and prevalence of Cronobacter spp. in plant and animal derived food sources: a systematic review and meta-analysis.

    PubMed

    Sani, Norrakiah Abdullah; Odeyemi, Olumide A

    2015-01-01

    Cronobacter species are motile, non-spore forming, Gram negative emerging opportunistic pathogens mostly associated with bacteremia, meningitis, septicemia, brain abscesses and necrotizing enterocolitis in infected neonates, infants and immunocompromised adults. Members of the genus Cronobacter are previously associated with powdered infant formula although the main reservoir and routes of contamination are yet to be ascertained. This study therefore aim to summarize occurrence and prevalence of Cronobacter spp. from different food related sources. A retrospective systematic review and meta-analysis of peer reviewed primary studies reported between 2008 and 2014 for the occurrence and prevalence of Cronobacter spp. in animal and plant related sources was conducted using "Cronobacter isolation", "Cronobacter detection" and "Cronobacter enumeration" as search terms in the following databases: Web of Science (Science Direct) and ProQuest. Data extracted from the primary studies were then analyzed with meta-analysis techniques for effect rate and fixed effects was used to explore heterogeneity between the sources. Publication bias was evaluated using funnel plot. A total of 916 articles were retrieved from the data bases of which 28 articles met inclusion criteria. Cronobacter spp. could only be isolated from 103 (5.7 %) samples of animal related food while 123 (19 %) samples of plant related food samples harbors the bacteria. The result of this study shows that occurrence of Cronobacter was more prevalent in plant related sources with overall prevalence rate of 20.1 % (95 % CI 0.168-0.238) than animal originated sources with overall prevalence rate of 8 % (95 % CI 0.066-0.096). High heterogeneity (I (2) = 84) was observed mostly in plant related sources such as herbs, spices and vegetables compared to animal related sources (I (2) = 82). It could be observed from this study that plant related sources serve as reservoir and contamination routes of Cronobacter

  4. 5 CFR 894.501 - When may I enroll?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false When may I enroll? 894.501 Section 894.501 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and Changing Enrollment § 894...

  5. 5 CFR 894.103 - How do I enroll?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false How do I enroll? 894.103 Section 894.103 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.103 How do I...

  6. 5 CFR 894.103 - How do I enroll?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false How do I enroll? 894.103 Section 894.103 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.103 How do I...

  7. 5 CFR 894.103 - How do I enroll?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false How do I enroll? 894.103 Section 894.103 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.103 How do I...

  8. Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium in powdered weaning food by electron-beam irradiation

    NASA Astrophysics Data System (ADS)

    Hong, Yun-Hee; Park, Ji-Yong; Park, Jong-Hyun; Chung, Myong-Soo; Kwon, Ki-Sung; Chung, Kyungsook; Won, Misun; Song, Kyung-Bin

    2008-09-01

    Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium were evaluated in powdered weaning food using electron-beam irradiation. E. sakazakii, B. cereus, and S. typhimurium were eliminated by irradiation at 16, 8, and 8 kGy, respectively. The D10-vlaues of E. sakazakii, B. cereus, and S. typhimurium inoculated on powdered weaning food were 4.83, 1.22, and 0.98 kGy, respectively. The results suggest that electron-beam irradiation should inhibit the growth of pathogenic bacteria on baby food without impairing qualities.

  9. Web-based computer-aided-diagnosis (CAD) system for bone age assessment (BAA) of children

    NASA Astrophysics Data System (ADS)

    Zhang, Aifeng; Uyeda, Joshua; Tsao, Sinchai; Ma, Kevin; Vachon, Linda A.; Liu, Brent J.; Huang, H. K.

    2008-03-01

    Bone age assessment (BAA) of children is a clinical procedure frequently performed in pediatric radiology to evaluate the stage of skeletal maturation based on a left hand and wrist radiograph. The most commonly used standard: Greulich and Pyle (G&P) Hand Atlas was developed 50 years ago and exclusively based on Caucasian population. Moreover, inter- & intra-observer discrepancies using this method create a need of an objective and automatic BAA method. A digital hand atlas (DHA) has been collected with 1,400 hand images of normal children from Asian, African American, Caucasian and Hispanic descends. Based on DHA, a fully automatic, objective computer-aided-diagnosis (CAD) method was developed and it was adapted to specific population. To bring DHA and CAD method to the clinical environment as a useful tool in assisting radiologist to achieve higher accuracy in BAA, a web-based system with direct connection to a clinical site is designed as a novel clinical implementation approach for online and real time BAA. The core of the system, a CAD server receives the image from clinical site, processes it by the CAD method and finally, generates report. A web service publishes the results and radiologists at the clinical site can review it online within minutes. This prototype can be easily extended to multiple clinical sites and will provide the foundation for broader use of the CAD system for BAA.

  10. Growth inhibition of Cronobacter spp. strains in reconstituted powdered infant formula acidified with organic acids supported by natural stomach acidity.

    PubMed

    Zhu, S; Schnell, S; Fischer, M

    2013-09-01

    Cronobacter is associated with outbreaks of rare, but life-threatening cases of meningitis, necrotizing enterocolitis, and sepsis in newborns. This study was conducted to determine the effect of organic acids on growth of Cronobacter in laboratory medium and reconstituted powdered infant formula (PIF) as well as the bacteriostatic effect of slightly acidified infant formula when combined with neonatal gastric acidity. Inhibitory effect of seven organic acids on four acid sensitive Cronobacter strains was determined in laboratory medium with broth dilution method at pH 5.0, 5.5 and 6.0. Acetic, butyric and propionic acids were most inhibitive against Cronobacter in the laboratory medium. The killing effect of these three acids was partially buffered in reconstituted PIF. Under neonatal gastric acid condition of pH 5.0, the slightly acidified formula which did not exert inhibition effect solely reduced significantly the Cronobacter populations. A synergistic effect of formula moderately acidified with organic acid combined with the physiological infant gastric acid was visible in preventing the rapid growth of Cronobacter in neonatal stomach. The study contributed to a better understanding of the inhibitory effect of organic acids on Cronobacter growth in different matrixes and provided new ideas in terms of controlling bacteria colonization and translocation by acidified formula. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. 5 CFR 894.302 - What is an excluded position?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false What is an excluded position? 894.302 Section 894.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Eligibility § 894.302 What is an...

  12. 5 CFR 894.302 - What is an excluded position?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false What is an excluded position? 894.302 Section 894.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Eligibility § 894.302 What is an...

  13. 5 CFR 894.401 - How do I pay premiums?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false How do I pay premiums? 894.401 Section 894.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.401 How do I pay...

  14. 5 CFR 894.401 - How do I pay premiums?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false How do I pay premiums? 894.401 Section 894.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.401 How do I pay...

  15. Survival and growth of Enterobacter sakazakii in infant cereal as affected by composition, reconstitution liquid, and storage temperature.

    PubMed

    Lin, Li-Chun; Beuchat, Larry R

    2007-06-01

    Invasive infections caused by Enterobacter sakazakii have occurred predominantly in low-birth-weight neonates and infants younger than 2 months of age. However, infections have also occurred in healthy infants up to 8 months of age and in immunocompromised children up to 4 years of age. The ability of E. sakazakii to survive and grow in infant cereals as affected by composition of the cereal, composition of the reconstitution liquid, and temperature is unknown. A study was done to determine the survival and growth characteristics of E. sakazakii initially at populations of 0.005 and 0.52 CFU/ml of infant rice cereal, oatmeal cereal, or rice with mixed fruit cereal reconstituted with water, milk, or apple juice. Reconstituted cereals were stored at 4, 12, 21, and 30 degrees C, and populations were monitored for up to 72 h. Growth did not occur in reconstituted cereals stored at 4 degrees C or in cereals reconstituted with apple juice and stored at 12 degrees C. Populations (> or =1 CFU/ml) were detected in cereals reconstituted with water or milk and stored at 12, 21, and 30 degres C for 24, 8, and 4 h, respectively. The composition of infant cereals did not markedly affect the survival or growth of E. sakazakii in reconstituted cereals. Populations of E. sakazakii in reconstituted cereal decreased with increases in populations of mesophilic aerobic microflora up to 8 to 9 log CFU/ml, which was concurrent with decreases in pH. E. sakazakii, initially at 2.62 log CFU/ml of rice cereal reconstituted with apple juice (pH 4.32), survived at 40C for at least 14 days. The pathogen grew at 21 and 30 degrees C within 2 days and then decreased to undetectable levels (<1 CFU/10 ml) in cereal stored at 21 degrees C for 5 days or 30'C for 4 days. Initially, at 7.32 log CFU/ml, E. sakazakii was detected in rice cereal stored at 4 degrees C for 50 days. It is recommended that reconstituted infant cereals stored at 21 or 30 degrees C be discarded within 4 h after preparation or

  16. Evaluation of an automated repetitive sequence-based PCR system for subtyping Enterobacter sakazakii.

    PubMed

    Healy, B; Mullane, N; Collin, V; Mailler, S; Iversen, C; Chatellier, S; Storrs, M; Fanning, S

    2008-07-01

    Enterobacter sakazakii is regarded as a ubiquitous organism that can be isolated from a wide range of foods and environments. Infection in at-risk infants has been epidemiologically linked to the consumption of contaminated powdered infant formula. Preventing the dissemination of this pathogen in a powdered infant formula manufacturing facility is an important step in ensuring consumer confidence in a given brand together with the protection of the health status of a vulnerable population. In this study we report the application of a repetitive sequence-based PCR typing method to subtype a previously well-characterized collection of E. sakazakii isolates of diverse origin. While both methods successfully discriminated between the collection of isolates, repetitive sequence-based PCR identified 65 types, whereas pulsed-field gel electrophoresis identified 110 types showing > or =95% similarity. The method was quick and easy to perform, and our data demonstrated the utility and value of this approach to monitor in-process contamination, which could potentially contribute to a reduction in the transmission of E. sakazakii.

  17. Application of pulsed-field gel electrophoresis to characterise and trace the prevalence of Enterobacter sakazakii in an infant formula processing facility.

    PubMed

    Mullane, N R; Whyte, P; Wall, P G; Quinn, T; Fanning, S

    2007-05-01

    Enterobacter sakazakii (E. sakazakii) contamination of powdered infant formula (PIF) and its processing environment was monitored between April 2005 and March 2006. The purpose of the monitoring programme was to locate points of contamination, investigate clonal persistence, and identify possible dissemination routes along the processing chain. A total of 80 E. sakazakii isolates were recovered from the manufacturing facility. The overall frequency of isolation of E. sakazakii in intermediate and final product was 2.5%, while specific locations in the processing environment were contaminated at frequencies up to 31%. All E. sakazakii isolates were characterised by pulsed-field gel electrophoresis (PFGE). XbaI macrorestriction digests yielded 19 unique pulse-types that could be grouped into 6 clusters of between 5 and 32 isolates. The formation of large clusters was consistent with the presence of a number of clones in the manufacturing environment. While the majority of isolates were of environmental origin (72.5%), no cluster was confined to one specific location and indistinguishable PFGE profiles were generated from isolates cultured from the manufacturing environment, sampling points along the processing chain and from intermediate and final product. These findings suggest that the manufacturing environment serves as a key route for sporadic contamination of PIF. These data will support the development of efficient intervention measures contributing to the reduction of E. sakazakii in the PIF processing chain.

  18. 5 CFR 894.306 - Are foster children eligible as family members?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Are foster children eligible as family members? 894.306 Section 894.306 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Eligibility § 894...

  19. 5 CFR 894.306 - Are foster children eligible as family members?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Are foster children eligible as family members? 894.306 Section 894.306 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Eligibility § 894...

  20. 5 CFR 894.404 - May I opt out of premium conversion?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false May I opt out of premium conversion? 894.404 Section 894.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.404 May I...

  1. 5 CFR 894.404 - May I opt out of premium conversion?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false May I opt out of premium conversion? 894.404 Section 894.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.404 May I...

  2. 5 CFR 894.504 - When is my enrollment effective?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false When is my enrollment effective? 894.504 Section 894.504 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and Changing...

  3. 5 CFR 894.504 - When is my enrollment effective?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false When is my enrollment effective? 894.504 Section 894.504 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and Changing...

  4. Confirmation and Identification of Salmonella spp., Cronobacter spp., and Other Gram-Negative Organisms by the Bruker MALDI Biotyper Method: Collaborative Study, First Action 2017.09.

    PubMed

    Bastin, Benjamin; Bird, Patrick; Benzinger, M Joseph; Crowley, Erin; Agin, James; Goins, David; Sohier, Daniele; Timke, Markus; Shi, Gongyi; Kostrzewa, Markus

    2018-04-27

    The Bruker MALDI Biotyper ® method utilizes matrix-assisted laser desorption/ionizationtime-of-flight (MALDI-TOF) MS for the rapid and accurate identification and confirmation of Gram-negative bacteria from select media types. The alternative method was evaluated using nonselective and selective agars to identify Cronobacter spp., Salmonella spp., and select Gram-negative bacteria. Results obtained by the Bruker MALDI Biotyper were compared to the traditional biochemical methods as prescribed in the appropriate reference methods. Two collaborative studies were organized, one in the United States focusing on Cronobacter spp. and other Gram-negative bacteria, and one in Europe focusing on Salmonella spp. and other Gram-negative bacteria. Fourteen collaborators from seven laboratories located within the United States participated in the first collaborative study for Cronobacter spp. Fifteen collaborators from 15 service laboratories located within Europe participated in the second collaborative study for Salmonella spp. For each target organism (either Salmonella spp. or Cronobacter spp.), a total of 24 blind-coded isolates were evaluated. In each set of 24 organisms, there were 16 inclusivity organisms ( Cronobacter spp. or Salmonella spp.) and 8 exclusivity organisms (closely related non- Cronobacter spp. and non- Salmonella spp. Gram-negative organisms). After testing was completed, the total percentage of correct identifications from each agar type for each strain was determined at a percentage of 100.0% to the genus level for the Cronobacter study and a percentage of 100.0% to the genus level for the Salmonella study. For both non- Cronobacter and non- Salmonella organisms, a percentage of 100.0% was correctly identified. The results indicated that the alternative method produced equivalent results when compared to the confirmatory procedures specified by each reference method.

  5. Taxonomic evaluation of the genus Enterobacter based on multilocus sequence analysis (MLSA): proposal to reclassify E. nimipressuralis and E. amnigenus into Lelliottia gen. nov. as Lelliottia nimipressuralis comb. nov. and Lelliottia amnigena comb. nov., respectively, E. gergoviae and E. pyrinus into Pluralibacter gen. nov. as Pluralibacter gergoviae comb. nov. and Pluralibacter pyrinus comb. nov., respectively, E. cowanii, E. radicincitans, E. oryzae and E. arachidis into Kosakonia gen. nov. as Kosakonia cowanii comb. nov., Kosakonia radicincitans comb. nov., Kosakonia oryzae comb. nov. and Kosakonia arachidis comb. nov., respectively, and E. turicensis, E. helveticus and E. pulveris into Cronobacter as Cronobacter zurichensis nom. nov., Cronobacter helveticus comb. nov. and Cronobacter pulveris comb. nov., respectively, and emended description of the genera Enterobacter and Cronobacter.

    PubMed

    Brady, Carrie; Cleenwerck, Ilse; Venter, Stephanus; Coutinho, Teresa; De Vos, Paul

    2013-07-01

    The taxonomy of Enterobacter has a complicated history, with several species transferred to and from this genus. Classification of strains is difficult owing to its polyphyletic nature, based on 16S rRNA gene sequences. It has been previously acknowledged that Enterobacter contains species which should be transferred to other genera. In an attempt to resolve the taxonomy of Enterobacter, MLSA based on partial sequencing of protein-encoding genes (gyrB, rpoB, infB and atpD) was performed on the type strains and reference strains of Enterobacter, Cronobacter and Serratia species, as well as members of the closely related genera Citrobacter, Klebsiella, Kluyvera, Leclercia, Mangrovibacter, Raoultella and Yokenella. Phylogenetic analyses of the concatenated nucleotide sequences revealed that Enterobacter can be divided into five strongly supported MLSA groups, suggesting that the species should be reclassified into five different genera. Further support for this was provided by a concatenated amino acid tree, phenotypic characteristics and fatty acid profiles, enabling differentiation of the MLSA groups. Three novel genera are proposed: Lelliottia gen. nov., Pluralibacter gen. nov. and Kosakonia gen. nov. and the following new combinations: Lelliottia nimipressuralis comb. nov., Lelliottia amnigena comb. nov., Pluralibacter gergoviae comb. nov., Pluralibacter pyrinus comb. nov., Kosakonia cowanii comb. nov., Kosakonia radicincitans comb. nov., Kosakonia oryzae comb. nov., Kosakonia arachidis comb. nov., Cronobacter helveticus comb. nov. and Cronobacter pulveris comb. nov. Additionally, the novel epithet Cronobacter zurichensis nom. nov. is proposed for the reclassification of Enterobacter turicensis into the genus Cronobacter, as Cronobacter turicensis (Iversen et al., 2008) is already in use. Copyright © 2013 Elsevier GmbH. All rights reserved.

  6. Growth and survival of Enterobacter sakazakii in human breast milk with and without fortifiers as compared to powdered infant formula.

    PubMed

    Lenati, Raquel F; O'Connor, Deborah L; Hébert, Karine C; Farber, Jeffrey M; Pagotto, Franco J

    2008-02-29

    Enterobacter sakazakii infections often involve debilitated neonates consuming contaminated reconstituted powdered infant formula. There is the possibility that expressed human breast milk can become contaminated with E. sakazakii in the hospital or home setting and through the use of contaminated breast milk fortifiers. In addition, although breast milk has been shown to have some antimicrobial effects, this has not been extensively researched in regards to E. sakazakii. Thus, we examined the survival and growth of 9 strains of E. sakazakii in breast milk, human breast milk with fortifiers and powdered infant formula at 10, 23 and 37 degrees C. The average generation times for clinical, food and environmental isolates in breast milk were 0.94+/-0.04, 0.75+/-0.04 and 0.84+/-0.04 h at 23 degrees C; and 0.51+/-0.03, 0.33+/-0.03 and 0.42+/-0.03 h at 37 degrees C, respectively. E. sakazakii was able to survive up to 12 days in breast milk with fortifiers at 10 degrees C. However, its average generation times among replicates and isolate sources ranged from 11.97+/-3.82 to 27.08+/-4.54 h in breast milk at 10 degrees C. Interestingly, average generation times in breast milk with fortifiers at 23 degrees C (0.83+/-0.05, 0.93+/-0.06 and 0.96+/-0.06 h) and 37 degrees C (0.41+/-0.04, 0.51+/-0.05 and 0.54+/-0.05 h) were longer than in powdered infant formula and breast milk at the same temperatures, indicating that human breast milk fortifiers may have an inhibitory effect on the growth of E. sakazakii. However, the intrinsically ascribed antimicrobial properties of breast milk do not appear to inhibit the growth of this foodborne pathogen in-vitro.

  7. Selected Pathogens of Concern to Industrial Food Processors: Infectious, Toxigenic, Toxico-Infectious, Selected Emerging Pathogenic Bacteria

    NASA Astrophysics Data System (ADS)

    Behling, Robert G.; Eifert, Joseph; Erickson, Marilyn C.; Gurtler, Joshua B.; Kornacki, Jeffrey L.; Line, Erick; Radcliff, Roy; Ryser, Elliot T.; Stawick, Bradley; Yan, Zhinong

    This chapter, written by several contributing authors, is devoted to discussing selected microbes of contemporary importance. Microbes from three categories are described by the following: (1) infectious invasive agents like Salmonella, Listeria monocytogenes, and Campylobacter; (2) toxigenic pathogens such as Staphylococcus aureus, Bacillus cereus, and Clostridium botulinum; and (3) toxico-infectious agents like enterohemorrhagic Escherichia coli and Clostridium perfringens. In addition, emerging pathogens, like Cronobacter (Enterobacter) sakazakii, Arcobacter spp., and Mycobacterium avium subspecies paratuberculosis are also described.

  8. 5 CFR 894.301 - Am I eligible to enroll in the FEDVIP?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Am I eligible to enroll in the FEDVIP? 894.301 Section 894.301 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Eligibility § 894...

  9. 5 CFR 894.301 - Am I eligible to enroll in the FEDVIP?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Am I eligible to enroll in the FEDVIP? 894.301 Section 894.301 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Eligibility § 894...

  10. 5 CFR 894.510 - When may I decrease my type of enrollment?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false When may I decrease my type of enrollment? 894.510 Section 894.510 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL... Changing Enrollment § 894.510 When may I decrease my type of enrollment? (a) You may decrease your type of...

  11. Rapid Detection of Enterobacter Sakazakii in milk Powder using amino modified chitosan immunomagnetic beads.

    PubMed

    Zhu, Yinglian; Wang, Dongfeng

    2016-12-01

    Chitosan immunomagnetic beads (CIBs) were first prepared through converting hydroxyl groups of natural polymer material-chitosan into amino groups using epichlorohydrin and ethylenediamine as modification agent and then coupling with polyclonal antibodies of Enterobacter sakazakii using glutaraldehyde as cross-linking agent. The beads before coupling with antibodies were characterized by magnetic property measurement, FTIR, SEM and XRD technologies. In the assay a natural polysaccharide-chitosan, which has good biological and chemical properties such as non-toxicity, biocompatibility and high chemical reactivity was first used for synthesis of immunomagnetic beads. The detection method first established in this paper that combined the beads with chromogenic medium together to rapid detect E. sakazakii in milk powder could greatly improve the detection specificity and working efficiency. The beads exhibited a maximum capturing capacity of 1×10 6 cfu/g with the detection sensitivity of 4cfu/g. The results demonstrate that the assay is a straightforward, specific and sensitive alternative for rapid detection of E.sakazakii in food matrix. The total analysis time was as little as about 25h, which greatly shorten the detection time. The method can provides new ideas not only to preparation technique of immunomagnetic beads but to imunne detection technique in food safety. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. 5 CFR 894.104 - Who makes enrollment decisions and reconsiderations?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Who makes enrollment decisions and reconsiderations? 894.104 Section 894.104 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and...

  13. 5 CFR 894.104 - Who makes enrollment decisions and reconsiderations?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Who makes enrollment decisions and reconsiderations? 894.104 Section 894.104 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and...

  14. 5 CFR 894.503 - Are belated enrollments or changes allowed?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Are belated enrollments or changes allowed? 894.503 Section 894.503 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and...

  15. 5 CFR 894.503 - Are belated enrollments or changes allowed?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Are belated enrollments or changes allowed? 894.503 Section 894.503 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and...

  16. 5 CFR 894.104 - Who makes enrollment decisions and reconsiderations?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Who makes enrollment decisions and reconsiderations? 894.104 Section 894.104 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and...

  17. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abbasifar, Reza; Griffiths, Mansel W.; Sabour, Parviz M.

    Cronobacter sakazakii is a Gram-negative pathogen found in milk-based formulae that causes infant meningitis. Bacteriophages have been proposed to control bacterial pathogens; however, comprehensive knowledge about a phage is required to ensure its safety before clinical application. We have characterized C. sakazakii phage vB{sub C}saM{sub G}AP32 (GAP32), which possesses the second largest sequenced phage genome (358,663 bp). A total of 571 genes including 545 protein coding sequences and 26 tRNAs were identified, thus more genes than in the smallest bacterium, Mycoplasma genitalium G37. BLASTP and HHpred searches, together with proteomic analyses reveal that only 23.9% of the putative proteins havemore » defined functions. Some of the unique features of this phage include: a chromosome condensation protein, two copies of the large subunit terminase, a predicted signal-arrest-release lysin; and an RpoD-like protein, which is possibly involved in the switch from immediate early to delayed early transcription. Its closest relatives are all extremely large myoviruses, namely coliphage PBECO4 and Klebsiella phage vB{sub K}leM-RaK2, with whom it shares approximately 44% homologous proteins. Since the homologs are not evenly distributed, we propose that these three phages belong to a new subfamily. - Highlights: • Cronobacter sakazakii phage vB{sub C}saM{sub G}AP32 has a genome of 358,663 bp. • It encodes 545 proteins which is more than Mycoplasma genitalium G37. • It is a member of the Myoviridae. • It is peripherally related to coliphage PBECO4 and Klebsiella phage vB{sub K}leM-RaK2. • GAP32 encodes a chromosome condensation protein.« less

  18. Altering the Composition of Caseicins A and B as a Means of Determining the Contribution of Specific Residues to Antimicrobial Activity ▿

    PubMed Central

    Norberg, Sarah; O'Connor, Paula M.; Stanton, Catherine; Ross, R. Paul; Hill, Colin; Fitzgerald, Gerald F.; Cotter, Paul D.

    2011-01-01

    Caseicin A (IKHQGLPQE) and caseicin B (VLNENLLR) are antimicrobial peptides generated through the bacterial fermentation of sodium caseinate, and on the basis of this and previous studies, they are active against many Gram-negative pathogens (Cronobacter sakazakii, Cronobacter muytjensii, Salmonella enterica serovar Typhimurium, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas fluorescens) as well as the Gram-positive organism Staphylococcus aureus. Here we describe further studies with the aim of establishing the importance of specific (charged and nonpolar aliphatic) residues within the caseicin peptides and the effects that they have on the bacteria listed above. In order to achieve our objective, we created four derivatives of each caseicin (A1 to A4 and B1 to B4) in which specific residues were altered, and results obtained with these derivatives were compared to wild-type caseicin activity. Although conversion of cationic residues to alanine in caseicins B1 (R8A change), A1 (K2A), A2 (H3A), and A3 (K2A-H3A) generally resulted in their activity against microbial targets being reduced or unaltered, C. sakazakii DPC6440 was unusual in that it displayed enhanced sensitivity to three peptides (caseicins A1, A3, and B2) in which positively charged residues had been eliminated. While the replacement of leucine with alanine in selected variants (B3 and B4) resulted in reduced activity against a number of strains of Cronobacter and, in some cases, S. Typhimurium, these changes enhanced the activities of these peptides against DPC6440 and a number of S. aureus strains. It is thus apparent that the importance of specific residues within the caseicin peptides is dependent on the strain being targeted. PMID:21296933

  19. 5 CFR 894.101 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.101 Definitions... Federal Employees Dental and Vision Insurance Program (FEDVIP). Annuitant means an individual defined at 5... Management contracts to provide dental and/or vision benefits. Child means one of the following: (1)(i) A...

  20. 5 CFR 894.101 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.101 Definitions... Federal Employees Dental and Vision Insurance Program (FEDVIP). Annuitant means an individual defined at 5... Management contracts to provide dental and/or vision benefits. Child means one of the following: (1)(i) A...

  1. 5 CFR 894.101 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.101 Definitions... Federal Employees Dental and Vision Insurance Program (FEDVIP). Annuitant means an individual defined at 5... Management contracts to provide dental and/or vision benefits. Child means one of the following: (1)(i) A...

  2. Microbiological quality of selected spices and herbs including the presence of Cronobacter spp.

    PubMed

    Garbowska, M; Berthold-Pluta, A; Stasiak-Różańska, L

    2015-08-01

    The cultivation of spices and herbs in parts of the world characterized by warm climate and high humidity provides excellent conditions for the development of microorganisms, including the undesirable ones. The aim of this study was to determine the microbiological quality of spices and herbs available on the Polish market, considering the occurrence of Cronobacter species bacteria. Analyses covered 60 samples of commercial spices and herbs, including 38 samples of dried herbs (basil, bay leaves, thyme, oregano, tarragon, marjoram, dill, parsley, rosemary, lovage) and 16 samples of seasoning blends as well as 6 samples of spices seeds and fruits (pimento, black pepper, coriander). All samples were tested for the total count of aerobic mesophilic bacteria (TAMB) and for the presence of Cronobacter spp. In most of the samples of spices and herbs (60.0%), the TAMB did not exceed 10(4) CFU/g, and the level regarded as unacceptable (>10(6) CFU/g) was not identified in any of the samples. The presence of Cronobacter spp. was demonstrated in 10 (16.7%) samples of the analyzed products, however these were mainly samples of herbs (basil, tarragon, parsley) and one sample of a seasoning blend (Provence herbs). The highest microbiological contamination (TAMB) was found in samples of herbs (oregano, tarragon, basil) and in ready seasoning blends, in 21.1% and 25.0% of which the total count of aerobic mesophiles was in the range of 10(5)-10(6) CFU/g. In all samples of spices seeds and fruits (coriander, black pepper and pimento), the total count of aerobic bacteria reached <10(4) CFU/g. Results achieved in the study indicate good hygienic conditions in the production process of spices and herbs available on the Polish market. The study demonstrated also that dried spices and herbs may be carriers of Cronobacter species bacteria, though their presence in not often detected in products of this type. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Antimicrobial Activity of Kefir against Various Food Pathogens and Spoilage Bacteria

    PubMed Central

    Kim, Hyunsook

    2016-01-01

    Kefir is a unique fermented dairy product produced by a mixture of lactic acid bacteria, acetic acid bacteria, and yeast. Here, we compared the antimicrobial spectra of four types of kefirs (A, L, M, and S) fermented for 24, 36, 48, or 72 h against eight food-borne pathogens. Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Enterococcus faecalis, Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, and Cronobacter sakazakii were used as test strains, and antibacterial activity was investigated by the spot on lawn method. The spectra, potencies, and onsets of activity varied according to the type of kefir and the fermentation time. The broadest and strongest antimicrobial spectrum was obtained after at least 36-48 h of fermentation for all kefirs, although the traditional fermentation method of kefir is for 18-24 h at 25℃. For kefir A, B. cereus, E. coli, S. Enteritidis, P. aeruginosa, and C. sakazakii were inhibited, while B. cereus, S. aureus, E. coli, S. Enteritidis, P. aeruginosa, and C. sakazakii were inhibited to different extents by kefirs L, M, and S. Remarkably, S. aureus, S. Enteritidis, and C. sakazakii were only inhibited by kefirs L, M, and S, and L. monocytogenes by kefir M after fermentation for specific times, suggesting that the antimicrobial activity is attributable not only to a low pH but also to antimicrobial substances secreted during the fermentation. PMID:28115890

  4. Antimicrobial Activity of Kefir against Various Food Pathogens and Spoilage Bacteria.

    PubMed

    Kim, Dong-Hyeon; Jeong, Dana; Kim, Hyunsook; Kang, Il-Byeong; Chon, Jung-Whan; Song, Kwang-Young; Seo, Kun-Ho

    2016-01-01

    Kefir is a unique fermented dairy product produced by a mixture of lactic acid bacteria, acetic acid bacteria, and yeast. Here, we compared the antimicrobial spectra of four types of kefirs (A, L, M, and S) fermented for 24, 36, 48, or 72 h against eight food-borne pathogens. Bacillus cereus , Staphylococcus aureus , Listeria monocytogenes , Enterococcus faecalis , Escherichia coli , Salmonella Enteritidis , Pseudomonas aeruginosa , and Cronobacter sakazakii were used as test strains, and antibacterial activity was investigated by the spot on lawn method. The spectra, potencies, and onsets of activity varied according to the type of kefir and the fermentation time. The broadest and strongest antimicrobial spectrum was obtained after at least 36-48 h of fermentation for all kefirs, although the traditional fermentation method of kefir is for 18-24 h at 25℃. For kefir A, B. cereus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited, while B. cereus , S. aureus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited to different extents by kefirs L, M, and S. Remarkably, S. aureus , S . Enteritidis, and C. sakazakii were only inhibited by kefirs L, M, and S, and L. monocytogenes by kefir M after fermentation for specific times, suggesting that the antimicrobial activity is attributable not only to a low pH but also to antimicrobial substances secreted during the fermentation.

  5. 5 CFR 894.506 - How often will there be open seasons?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false How often will there be open seasons? 894.506 Section 894.506 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and Changing...

  6. 5 CFR 894.506 - How often will there be open seasons?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false How often will there be open seasons? 894.506 Section 894.506 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and Changing...

  7. 5 CFR 894.105 - Who may correct an error in my enrollment?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Who may correct an error in my enrollment? 894.105 Section 894.105 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and...

  8. 5 CFR 894.201 - What types of enrollments are available under FEDVIP?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false What types of enrollments are available under FEDVIP? 894.201 Section 894.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and...

  9. 5 CFR 894.201 - What types of enrollments are available under FEDVIP?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false What types of enrollments are available under FEDVIP? 894.201 Section 894.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and...

  10. 5 CFR 894.105 - Who may correct an error in my enrollment?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Who may correct an error in my enrollment? 894.105 Section 894.105 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and...

  11. 5 CFR 894.105 - Who may correct an error in my enrollment?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Who may correct an error in my enrollment? 894.105 Section 894.105 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and...

  12. 5 CFR 894.201 - What types of enrollments are available under FEDVIP?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false What types of enrollments are available under FEDVIP? 894.201 Section 894.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and...

  13. Surveillance and molecular typing of Cronobacter spp. in commercial powdered infant formula and follow-up formula from 2011 to 2013 in Shandong Province, China.

    PubMed

    Zhang, Huaning; Hou, Peibin; Lv, Hui; Chen, Yuzhen; Li, Xinpeng; Ren, Yanyan; Wang, Mei; Tan, Hailian; Bi, Zhenwang

    2017-05-01

    Infection with Cronobacter spp. leads to neonatal meningitis, necrotizing enterocolitis and bacteremia. Cronobacter spp. are reported to comprise an important pathogen contaminating powdered infant formula (PIF) and follow-up formula (FUF), although little is known about the contamination level of Cronobacter spp. in PIFs and FUFs in China. In total, 1032 samples were collected between 2011 and 2013. Forty-two samples were positive, including 1.6% in PIFs and 6.5% in FUFs. The strains were susceptible to most antibiotics except for cefoxitin. Pulsed-field gel electrophoresis after XbaI digestion produced a total of 36 banding patterns. The 38 strains were found in 27 sequence types (STs), of which nine types (ST454 to ST462) had not been reported in other countries. The clinically relevant strains obtained from the 38 isolates in the present study comprised three ST3, two ST4, two ST8 and one ST1. The contamination rate in the PIF and FUF has stayed at a relatively high level. The contamination rate of PIF was significantly lower than FUF. The isolates had high susceptibility to the antibiotics tested, except cefoxitin. There were polymorphisms between the Cronobacter spp. as indicated by pulsed-field gel electrophoresis and multilocus sequence typing. Therefore, contamination with Cronobacter spp. remains a current issue for commercial infant formulas in China. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  14. 5 CFR 894.308 - How do I establish the dependency of my recognized natural child?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false How do I establish the dependency of my recognized natural child? 894.308 Section 894.308 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT... Eligibility § 894.308 How do I establish the dependency of my recognized natural child? (a) Dependency is...

  15. 5 CFR 894.307 - Are disabled children age 22 or over eligible as family members?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Are disabled children age 22 or over eligible as family members? 894.307 Section 894.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT... Eligibility § 894.307 Are disabled children age 22 or over eligible as family members? A child age 22 or over...

  16. 5 CFR 894.307 - Are disabled children age 22 or over eligible as family members?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Are disabled children age 22 or over eligible as family members? 894.307 Section 894.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT... Eligibility § 894.307 Are disabled children age 22 or over eligible as family members? A child age 22 or over...

  17. 5 CFR 894.307 - Are disabled children age 22 or over eligible as family members?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Are disabled children age 22 or over eligible as family members? 894.307 Section 894.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT... Eligibility § 894.307 Are disabled children age 22 or over eligible as family members? A child age 22 or over...

  18. 38 CFR 1.894 - Annual goals and timetables.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... GENERAL PROVISIONS Part-Time Career Employment Program § 1.894 Annual goals and timetables. An departmentwide plan for promoting part-time employment opportunities will be developed annually. This plan will...

  19. 5 CFR 894.501 - When may I enroll?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and Changing Enrollment § 894... before you or an eligible family member loses other dental/vision coverage to 60 days after a QLE that...

  20. Actual distribution of Cronobacter spp. in industrial batches of powdered infant formula and consequences for performance of sampling strategies.

    PubMed

    Jongenburger, I; Reij, M W; Boer, E P J; Gorris, L G M; Zwietering, M H

    2011-11-15

    The actual spatial distribution of microorganisms within a batch of food influences the results of sampling for microbiological testing when this distribution is non-homogeneous. In the case of pathogens being non-homogeneously distributed, it markedly influences public health risk. This study investigated the spatial distribution of Cronobacter spp. in powdered infant formula (PIF) on industrial batch-scale for both a recalled batch as well a reference batch. Additionally, local spatial occurrence of clusters of Cronobacter cells was assessed, as well as the performance of typical sampling strategies to determine the presence of the microorganisms. The concentration of Cronobacter spp. was assessed in the course of the filling time of each batch, by taking samples of 333 g using the most probable number (MPN) enrichment technique. The occurrence of clusters of Cronobacter spp. cells was investigated by plate counting. From the recalled batch, 415 MPN samples were drawn. The expected heterogeneous distribution of Cronobacter spp. could be quantified from these samples, which showed no detectable level (detection limit of -2.52 log CFU/g) in 58% of samples, whilst in the remainder concentrations were found to be between -2.52 and 2.75 log CFU/g. The estimated average concentration in the recalled batch was -2.78 log CFU/g and a standard deviation of 1.10 log CFU/g. The estimated average concentration in the reference batch was -4.41 log CFU/g, with 99% of the 93 samples being below the detection limit. In the recalled batch, clusters of cells occurred sporadically in 8 out of 2290 samples of 1g taken. The two largest clusters contained 123 (2.09 log CFU/g) and 560 (2.75 log CFU/g) cells. Various sampling strategies were evaluated for the recalled batch. Taking more and smaller samples and keeping the total sampling weight constant, considerably improved the performance of the sampling plans to detect such a type of contaminated batch. Compared to random sampling

  1. 5 CFR 894.303 - What happens to my enrollment if I transfer to an excluded position?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... FEDVIP and then transfer to an excluded position, you lose all rights to enroll at that time. ... transfer to an excluded position? 894.303 Section 894.303 Administrative Personnel OFFICE OF PERSONNEL... PROGRAM Eligibility § 894.303 What happens to my enrollment if I transfer to an excluded position? (a) If...

  2. 5 CFR 894.403 - Are FEDVIP premiums paid on a pre-tax basis?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Are FEDVIP premiums paid on a pre-tax basis? 894.403 Section 894.403 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage...

  3. 5 CFR 894.403 - Are FEDVIP premiums paid on a pre-tax basis?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Are FEDVIP premiums paid on a pre-tax basis? 894.403 Section 894.403 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage...

  4. Fate of Enterobacter sakazakii attached to or in biofilms on stainless steel upon exposure to various temperatures or relative humidities.

    PubMed

    Kim, Hoikyung; Bang, Jihyun; Beuchat, Larry R; Ryu, Jee-Hoon

    2008-05-01

    Survival of Enterobacter sakazakii dried on the surface of stainless steel and exposed to 43% relative humidity, as affected by temperature, was studied. Populations of E. sakazakii (7.4 to 8.6 log CFU per coupon) on coupons dried for 2 h at 22 degrees C decreased significantly (P < or = 0.05) at 4, 25, and 37 degrees C within 10, 3, and 1 day(s), respectively, but the pathogen remained viable for up to 60 days. At a given storage temperature and time, reductions were significantly greater when cells had been suspended in water rather than in infant formula before drying. Formation of biofilm by E. sakazakii on stainless steel immersed in M9 medium, which contains minimal concentrations of nutrients, and infant formula at 25 degrees C and subsequent survival of cells at 25 degrees C as affected by exposure to 23, 43, 68, 85, and 100% relative humidity were investigated. Some of the cells in these biofilms survived under all test relative humidities for up to 42 days. The overall order of survival as affected by relative humidity was 100 > 23 = 43 = 68 > 85% relative humidity, regardless of the medium in which the biofilm was formed. Reduction in viability of cells was significantly greater in biofilm that had formed in M9 medium than in biofilm formed in infant formula. Results indicate that infant formula provides protection for attached cells, as well as cells in biofilm, against lethality on exposure to desiccation. These results are useful when predicting the survival characteristics of E. sakazakii on stainless steel surfaces in processing and preparation kitchen environments.

  5. 5 CFR 894.505 - Are retroactive premiums paid with pre-tax dollars (premium conversion)?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Are retroactive premiums paid with pre-tax dollars (premium conversion)? 894.505 Section 894.505 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  6. 5 CFR 894.505 - Are retroactive premiums paid with pre-tax dollars (premium conversion)?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Are retroactive premiums paid with pre-tax dollars (premium conversion)? 894.505 Section 894.505 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  7. Satellite antenna dish acquired for use by the BAA

    NASA Astrophysics Data System (ADS)

    Ashton, T.

    2007-10-01

    The Radio Astronomy Group (RAG) of the BAA is pleased to announce it has obtained the use of the 2.4m diameter, fully-steerable satellite antenna dish residing on the roof of the National Space Centre (NSC) in Leicester (see Figure). The RAG is fortunate in having its assistant coordinator, Jeff Lashley, employed by the NSC as a technical support engineer and Jeff has worked tirelessly with coordinator Dr Laurence Newell in seeking permission for the Group to use the dish for radio astronomy purposes. Support has also been forthcoming via Terry Ashton, our university liaison officer, who works at the University of Leicester's Space Research Centre (SRC) which owns the dish.

  8. Metabolism and disposition of ABT-894, a novel α4β2 neuronal acetylcholine receptor agonist, in mice and monkeys.

    PubMed

    Liu, Hong; Fu, Wentao; Wetter, Jill; Xu, Hongyu; Guan, Zhiwen; Stuart, Patricia

    2014-06-01

    1.  Metabolism and disposition of ABT-894 was investigated in hepatocytes, in mice and monkeys receiving [(14)C]ABT-894. 2.  In hepatocytes, turnover rate of ABT-894 was slow in all species with more than 90% of parent remaining. M3 (carbamoyl glucuronide) and M6 (mono-oxidation) were detected across species. 3.  ABT-894 showed species-specific disposition profiles. ABT-894 was primarily eliminated by renal secretion in mice. Whereas, monkey mainly cleared ABT-894 metabolically. 4.  ABT-894 underwent two primary routes of metabolism in monkeys: N-carbamoyl glucuronidation to form M3 and oxidation product M1. M3 was the major metabolite in monkey excreta. M3 was observed in mice urine. Circulating levels of M3 in terms of M3/ABT-894 ratios were essentially absent in mice, but were high in monkeys. 5.  Understanding the species difference in the clearance mechanism is the key to the accurate projection of the human clearance and preclinical safety assessment. Lack of species difference in the metabolism of ABT-894 in hepatocytes certainly creates a challenge in predicting its metabolism and pharmacokinetics in human. Based on available metabolism and pharmacokinetic data of ABT-894 in human, monkey is the preferred species in predicting human clearance since it presents a similar clearance mechanism from that observed in human.

  9. Attachment of and biofilm formation by Enterobacter sakazakii on stainless steel and enteral feeding tubes.

    PubMed

    Kim, Hoikyung; Ryu, Jee-Hoon; Beuchat, Larry R

    2006-09-01

    Enterobacter sakazakii has been reported to form biofilms, but environmental conditions affecting attachment to and biofilm formation on abiotic surfaces have not been described. We did a study to determine the effects of temperature and nutrient availability on attachment and biofilm formation by E. sakazakii on stainless steel and enteral feeding tubes. Five strains grown to stationary phase in tryptic soy broth (TSB), infant formula broth (IFB), or lettuce juice broth (LJB) at 12 and 25 degrees C were examined for the extent to which they attach to these materials. Higher populations attached at 25 degrees C than at 12 degrees C. Stainless steel coupons and enteral feeding tubes were immersed for 24 h at 4 degrees C in phosphate-buffered saline suspensions (7 log CFU/ml) to facilitate the attachment of 5.33 to 5.51 and 5.03 to 5.12 log CFU/cm(2), respectively, before they were immersed in TSB, IFB, or LJB, followed by incubation at 12 or 25 degrees C for up to 10 days. Biofilms were not produced at 12 degrees C. The number of cells of test strains increased by 1.42 to 1.67 log CFU/cm(2) and 1.16 to 1.31 log CFU/cm(2) in biofilms formed on stainless steel and feeding tubes, respectively, immersed in IFB at 25 degrees C; biofilms were not formed on TSB and LJB at 25 degrees C, indicating that nutrient availability plays a major role in processes leading to biofilm formation on the surfaces of these inert materials. These observations emphasize the importance of temperature control in reconstituted infant formula preparation and storage areas in preventing attachment and biofilm formation by E. sakazakii.

  10. Molecular identification of potential denitrifying bacteria and use of D-optimal mixture experimental design for the optimization of denitrification process.

    PubMed

    Ben Taheur, Fadia; Fdhila, Kais; Elabed, Hamouda; Bouguerra, Amel; Kouidhi, Bochra; Bakhrouf, Amina; Chaieb, Kamel

    2016-04-01

    Three bacterial strains (TE1, TD3 and FB2) were isolated from date palm (degla), pistachio and barley. The presence of nitrate reductase (narG) and nitrite reductase (nirS and nirK) genes in the selected strains was detected by PCR technique. Molecular identification based on 16S rDNA sequencing method was applied to identify positive strains. In addition, the D-optimal mixture experimental design was used to optimize the optimal formulation of probiotic bacteria for denitrification process. Strains harboring denitrification genes were identified as: TE1, Agrococcus sp LN828197; TD3, Cronobacter sakazakii LN828198 and FB2, Pedicoccus pentosaceus LN828199. PCR results revealed that all strains carried the nirS gene. However only C. sakazakii LN828198 and Agrococcus sp LN828197 harbored the nirK and the narG genes respectively. Moreover, the studied bacteria were able to form biofilm on abiotic surfaces with different degree. Process optimization showed that the most significant reduction of nitrate was 100% with 14.98% of COD consumption and 5.57 mg/l nitrite accumulation. Meanwhile, the response values were optimized and showed that the most optimal combination was 78.79% of C. sakazakii LN828198 (curve value), 21.21% of P. pentosaceus LN828199 (curve value) and absence (0%) of Agrococcus sp LN828197 (curve value). Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Characterization and genome sequence of Dev2, a new T7-like bacteriophage infecting Cronobacter turicensis.

    PubMed

    Kajsík, Michal; Oslanecová, Lucia; Szemes, Tomáš; Hýblová, Michalea; Bilková, Andrea; Drahovská, Hana; Turňa, Ján

    2014-11-01

    Cronobacter spp. are opportunistic pathogenic bacteria that are responsible for severe infections in neonates. Powdered infant formula was confirmed to be the source in some cases. Bacteriophages offer a safe means for eliminating this pathogen. In the present study, we investigated the growth parameters and genome organization of a new bacteriophage, Dev2, isolated from sewage. The Dev2 phage contains DNA with a length of 39 kb and belongs to the T7 branch of the subfamily Autographivirinae, with the highest degree of identity to the phage K1F. The host specificity of Dev2 is limited to C. turicensis strains of the CT O:1 serotype. With a lower efficiency, this phage also infects some Salmonella and E. coli strains. The Dev2 phage can inactivate sensitive Cronobacter strains in reconstituted milk formula. The results obtained in this study are an important prerequisite for application of Dev2 in food control.

  12. 5 CFR 894.307 - Are disabled children age 22 or over eligible as family members?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Are disabled children age 22 or over eligible as family members? 894.307 Section 894.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM...

  13. 5 CFR 894.307 - Are disabled children age 22 or over eligible as family members?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Are disabled children age 22 or over eligible as family members? 894.307 Section 894.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM...

  14. 5 CFR 894.703 - How long does my coverage as an annuitant or compensationer last?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false How long does my coverage as an annuitant or compensationer last? 894.703 Section 894.703 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  15. 5 CFR 894.703 - How long does my coverage as an annuitant or compensationer last?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false How long does my coverage as an annuitant or compensationer last? 894.703 Section 894.703 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  16. 5 CFR 894.402 - Do the premiums I pay reflect the cost of providing benefits?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Do the premiums I pay reflect the cost of providing benefits? 894.402 Section 894.402 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost...

  17. 5 CFR 894.402 - Do the premiums I pay reflect the cost of providing benefits?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Do the premiums I pay reflect the cost of providing benefits? 894.402 Section 894.402 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Cost...

  18. 5 CFR 894.204 - May I be enrolled in more than one dental or vision plan at a time?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... or vision plan at a time? 894.204 Section 894.204 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and Types of Enrollment § 894.204 May I be enrolled in more than one dental or vision...

  19. 5 CFR 894.204 - May I be enrolled in more than one dental or vision plan at a time?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... or vision plan at a time? 894.204 Section 894.204 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and Types of Enrollment § 894.204 May I be enrolled in more than one dental or vision...

  20. 5 CFR 894.704 - What happens if I retire and then come back to work for the Federal Government?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false What happens if I retire and then come back to work for the Federal Government? 894.704 Section 894.704 Administrative Personnel OFFICE OF... INSURANCE PROGRAM Annuitants and Compensationers § 894.704 What happens if I retire and then come back to...

  1. 5 CFR 894.704 - What happens if I retire and then come back to work for the Federal Government?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false What happens if I retire and then come back to work for the Federal Government? 894.704 Section 894.704 Administrative Personnel OFFICE OF... INSURANCE PROGRAM Annuitants and Compensationers § 894.704 What happens if I retire and then come back to...

  2. 5 CFR 894.704 - What happens if I retire and then come back to work for the Federal Government?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false What happens if I retire and then come back to work for the Federal Government? 894.704 Section 894.704 Administrative Personnel OFFICE OF... INSURANCE PROGRAM Annuitants and Compensationers § 894.704 What happens if I retire and then come back to...

  3. 5 CFR 894.303 - What happens to my enrollment if I transfer to an excluded position?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false What happens to my enrollment if I transfer to an excluded position? 894.303 Section 894.303 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  4. 5 CFR 894.303 - What happens to my enrollment if I transfer to an excluded position?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false What happens to my enrollment if I transfer to an excluded position? 894.303 Section 894.303 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  5. The BAA Campaign for Dark Skies: Fifteen years on

    NASA Astrophysics Data System (ADS)

    Mizon, R.

    2004-06-01

    The starry sky is, unofficially but indubitably, a site of special scientific interest and an area of outstanding natural beauty - if it can be seen. The BAA's Campaign for Dark Skies (CfDS) was set up by concerned members in 1989, to counter the ever-growing tide of skyglow which has tainted the night sky over Britain since the 1950s. Once caused almost exclusively by poorly aimed streetlamps and building floodlights emitting light above the horizontal, skyglow is nowadays increasingly the result of vastly over-powered, poorly mounted household security lights and literally 'over-the-top' sports lighting. CfDS has grown into a network of 124 volunteer local officers, and several hundred committed supporters, who aim to persuade their local councils and relevant organisations of the benefits of well directed lighting, the motto being: the right amount of light, and only where needed.

  6. 5 CFR 894.511 - What are the QLEs that are consistent with decreasing my type of enrollment?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false What are the QLEs that are consistent with decreasing my type of enrollment? 894.511 Section 894.511 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION...

  7. 5 CFR 894.511 - What are the QLEs that are consistent with decreasing my type of enrollment?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false What are the QLEs that are consistent with decreasing my type of enrollment? 894.511 Section 894.511 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION...

  8. 5 CFR 894.304 - Am I eligible to enroll if I'm retired or receiving workers' compensation?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Am I eligible to enroll if I'm retired or receiving workers' compensation? 894.304 Section 894.304 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  9. 5 CFR 894.304 - Am I eligible to enroll if I'm retired or receiving workers' compensation?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Am I eligible to enroll if I'm retired or receiving workers' compensation? 894.304 Section 894.304 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  10. 5 CFR 894.701 - May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation? 894.701 Section 894.701 Administrative... DENTAL AND VISION INSURANCE PROGRAM Annuitants and Compensationers § 894.701 May I keep my dental and/or...

  11. 5 CFR 894.701 - May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation? 894.701 Section 894.701 Administrative... DENTAL AND VISION INSURANCE PROGRAM Annuitants and Compensationers § 894.701 May I keep my dental and/or...

  12. 5 CFR 894.701 - May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation? 894.701 Section 894.701 Administrative... DENTAL AND VISION INSURANCE PROGRAM Annuitants and Compensationers § 894.701 May I keep my dental and/or...

  13. 5 CFR 894.507 - After I'm enrolled, may I change from one dental or vision plan or plan option to another?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... dental or vision plan or plan option to another? 894.507 Section 894.507 Administrative Personnel OFFICE... AND VISION INSURANCE PROGRAM Enrollment and Changing Enrollment § 894.507 After I'm enrolled, may I change from one dental or vision plan or plan option to another? (a) You may change from one dental and...

  14. 5 CFR 894.507 - After I'm enrolled, may I change from one dental or vision plan or plan option to another?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... dental or vision plan or plan option to another? 894.507 Section 894.507 Administrative Personnel OFFICE... AND VISION INSURANCE PROGRAM Enrollment and Changing Enrollment § 894.507 After I'm enrolled, may I change from one dental or vision plan or plan option to another? (a) You may change from one dental and...

  15. 5 CFR 894.704 - What happens if I retire and then come back to work for the Federal Government?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false What happens if I retire and then come back to work for the Federal Government? 894.704 Section 894.704 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION...

  16. 5 CFR 894.704 - What happens if I retire and then come back to work for the Federal Government?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false What happens if I retire and then come back to work for the Federal Government? 894.704 Section 894.704 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION...

  17. 5 CFR 894.202 - If I enroll for self plus one, may I decide which family member to cover?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false If I enroll for self plus one, may I decide which family member to cover? 894.202 Section 894.202 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  18. 5 CFR 894.202 - If I enroll for self plus one, may I decide which family member to cover?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false If I enroll for self plus one, may I decide which family member to cover? 894.202 Section 894.202 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE...

  19. 5 CFR 894.801 - Will benefits be available in underserved areas?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Benefits in Underserved Areas § 894.801 Will benefits be available in underserved areas? (a) Dental and vision plans under... underserved areas. (b) In any area where a FEDVIP dental or vision plan does not meet OPM access standards...

  20. 5 CFR 894.801 - Will benefits be available in underserved areas?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Benefits in Underserved Areas § 894.801 Will benefits be available in underserved areas? (a) Dental and vision plans under... underserved areas. (b) In any area where a FEDVIP dental or vision plan does not meet OPM access standards...

  1. Association of Nitric Oxide Levels and Endothelial Nitric Oxide Synthase G894T Polymorphism with Coronary Artery Disease in the Iranian Population

    PubMed Central

    Mahmoodi, Khalil; Nasehi, Leila; Karami, Elham; Soltanpour, Mohammad Soleiman

    2016-01-01

    Purpose: The endothelial nitric oxide synthase (eNOS) G894T polymorphism has been reported to cause endothelial dysfunction and may have a role in the development of coronary artery disease (CAD). The aim of the present study was to investigate the association of eNOS G894T genetic polymorphism and plasma levels of nitric oxide (NO) with CAD risk in an Iranian population. Materials and Methods: We studied 200 patients with angiographically documented CAD and 100 matched controls. Analysis of G894T genetic polymorphism of eNOS was performed by polymerase chain reaction-restriction fragment length polymorphism method. Plasma levels of NO were determined using Griess method. Biochemical analysis was conducted by routine colorimetric methods. Results: Plasma levels of NO were significantly lower in CAD patients than control subjects (41.60±12.70 vs. 55.48±16.57, P=0.001). Also, the mean plasma levels of NO were significantly lower in T allele carriers of eNOS G894T polymorphism than G allele carriers (P<0.001). The genotype distribution and minor T allele frequency of eNOS G894T polymorphism significantly differed between CAD patients and control subjects (P<0.05). However, no significant association was found between the eNOS G894T polymorphism and the severity of CAD (number of diseased vessel) or the lipid profile of CAD patients (P>0.05). Conclusion: Reduced plasma level of NO is associated with increased risk of CAD in our population. Moreover, eNOS G894T polymorphism is a significant risk factor for CAD development via reducing the plasma levels of NO. However, eNOS G894T polymorphism is not a contributing factor for the severity of CAD. PMID:27699157

  2. Endothelial Nitric Oxide Synthase Gene G894T Polymorphism and Myocardial Infarction: A Meta-Analysis of 34 Studies Involving 21068 Subjects

    PubMed Central

    Luo, Jian-Quan; Wen, Jia-Gen; Zhou, Hong-Hao; Chen, Xiao-Ping; Zhang, Wei

    2014-01-01

    Background Researches have revealed that the endothelial nitric oxide synthase (eNOS) gene G894T polymorphism is associated with the risk of Myocardial infarction (MI), but the results remain conflicting. Objective and Methods A meta-analysis was conducted to investigate the association between eNOS G894T polymorphism and MI. Published studies from PubMed, Embase, CNKI and CBM databases were retrieved. The pooled odds ratios (ORs) for the association between eNOS G894T polymorphism and MI and their corresponding 95% confidence intervals (CIs) were estimated using the random- or fixed- effect model. Results A total of 34 studies including 8229 cases and 12839 controls were identified for the meta-analysis. The eNOS G894T polymorphism was significantly associated with MI under a homozygous genetic model (OR = 1.41, 95% CI = 1.08–1.84; P = 0.012), a recessive genetic model (OR = 1.35, 95% CI = 1.06–1.70; P = 0.014), a dominant genetic model (OR = 1.18, 95% CI = 1.04–1.34; P = 0.009). In the subgroup analysis by ethnicity (non-Asian and Asian), no significant association was observed between eNOS G894T polymorphism and MI risk among non-Asians (P>0.05), but a positive significant association was found among Asians (P<0.05). Conclusions The eNOS G894T polymorphism is associated with increased MI risk in Asians. The results indicate that ethnicity plays important roles in the association between eNOS G894T polymorphism and MI. PMID:24498040

  3. Effect of heat shock and recovery temperature on variability of single cell lag time of Cronobacter turicensis.

    PubMed

    Xu, Y Zh; Métris, A; Stasinopoulos, D M; Forsythe, S J; Sutherland, J P

    2015-02-01

    The effect of heat stress and subsequent recovery temperature on the individual cellular lag of Cronobacter turicensis was analysed using optical density measurements. Low numbers of cells were obtained through serial dilution and the time to reach an optical density of 0.035 was determined. Assuming the lag of a single cell follows a shifted Gamma distribution with a fixed shape parameter, the effect of recovery temperature on the individual lag of untreated and sublethally heat treated cells of Cr. turicensis were modelled. It was found that the shift parameter (Tshift) increased asymptotically as the temperature decreased while the logarithm of the scale parameter (θ) decreased linearly with recovery temperature. To test the validity of the model in food, growth of low numbers of untreated and heat treated Cr. turicensis in artificially contaminated infant first milk was measured experimentally and compared with predictions obtained by Monte Carlo simulations. Although the model for untreated cells slightly underestimated the actual growth in first milk at low temperatures, the model for heat treated cells was in agreement with the data derived from the challenge tests and provides a basis for reliable quantitative microbiological risk assessments for Cronobacter spp. in infant milk. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Synergistic effects of sodium hypochlorite and ultraviolet radiation in reducing the levels of selected foodborne pathogenic bacteria.

    PubMed

    Ha, Ji-Hyoung; Ha, Sang-Do

    2011-05-01

    The purpose of this study was to determine whether combined treatment would produce synergistic effects to facilitate the sterilization of food products during production relative to single treatment. To assess this hypothesis, we investigated the bactericidal effects of ultraviolet (UV) irradiation and a commercial chemical disinfectant, sodium hypochlorite (NaClO), on Bacillus cereus F4810/72, Cronobacter sakazakii KCTC 2949, Staphylococcus aureus ATCC 35556, Escherichia coli ATCC 10536, and Salmonella Typhimurium novobiocin/nalidixic acid in vitro. Various concentrations of NaClO (20, 60, 100, and 200 ppm NaClO) were tested along with exposure to UV radiation at various doses (6, 96, 216, 360, and 504 mW s/cm(2)). The combined NaClO/UV treatments resulted in greater reductions in bacterial counts than either treatment alone. The synergy values against B. cereus, C. sakazakii, S. aureus, Salmonella Typhimurium, and E. coli were 0.25-1.17, 0.33-1.97, 0.42-1.72, 0.02-1.44, and 0.01-0.85 log(10) CFU/mL, respectively. The results of this study suggest that a significant synergistic benefit results from combined NaClO/UV processing against food-borne pathogenic bacteria in vitro.

  5. 5 CFR 894.305 - Am I eligible to enroll if I am a former spouse receiving an apportionment of annuity?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Am I eligible to enroll if I am a former spouse receiving an apportionment of annuity? 894.305 Section 894.305 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION...

  6. 5 CFR 894.305 - Am I eligible to enroll if I am a former spouse receiving an apportionment of annuity?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Am I eligible to enroll if I am a former spouse receiving an apportionment of annuity? 894.305 Section 894.305 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION...

  7. G894T endothelial nitric oxide synthase polymorphism and ischemic stroke in Morocco

    PubMed Central

    Diakite, Brehima; Hamzi, Khalil; Slassi, Ilham; EL Yahyaoui, Mohammed; EL Alaoui, Moulay M.F.; Habbal, Rachida; Sellama, Nadifi

    2014-01-01

    Nitric oxide plays a major role in the regulation of cerebral blood flow and loss of its function leads to alteration of the vascular relaxation given its central role in the physiology of the vascular system. G894T eNOS polymorphism could have adverse effects on the expression and activity of endothelial nitric oxide synthase, which can result in functional impairment of the endothelium and contribute to the development of ischemic stroke in the different models of transmission. In this study, genotyping with PCR-RFLP and HRM (high resolution melting) methods were conducted on 165 ischemic stroke patients as well as 182 controls. The goal here was to compare genotyping with PCR-RLFP primer sequences of eNOS gene (size < 300 bp) to HRM. Our data suggests a statistically significant association between G894T eNOS polymorphism and ischemic stroke in recessive, dominant and additive models with P < 0.05 and odds ratio of 2.68 (1.08–6.70), 1.78 (1.16–2.73), and 1.71 (1.21–2.43) respectively. In sum, although the sample size is relatively small, it suggests that G894T eNOS polymorphism could be a potentially important genetic marker of ischemic stroke in the Moroccan population. Future studies should be conducted in this direction taking into consideration the functional activity of eNOS. PMID:25606419

  8. Using AVIRIS In The NASA BAA Project To Evaluate The Impact Of Natural Acid Drainage On Colorado Watersheds

    NASA Technical Reports Server (NTRS)

    Hauff, Phoebe L.; Coulter, David W.; Peters, Douglas C.; Sares, Matthew A.; Prosh, Eric C.; Henderson, Frederick B., III; Bird, David

    2004-01-01

    The Colorado Geological Survey and the co-authors of this paper were awarded one of 15 NASA Broad Agency Announcement (BAA) grants in 2001. The project focuses on the use of hyperspectral remote sensing to map acid-generating minerals that affect water quality within a watershed, and to identify the relative contributions of natural and anthropogenic sources to that drainage. A further objective is to define the most cost-effective remote sensing instrument configuration for this application.

  9. 5 CFR 894.507 - After I'm enrolled, may I change from one dental or vision plan or plan option to another?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... dental or vision plan or plan option to another? 894.507 Section 894.507 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL... change from one dental or vision plan or plan option to another? (a) You may change from one dental and...

  10. 5 CFR 894.507 - After I'm enrolled, may I change from one dental or vision plan or plan option to another?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... dental or vision plan or plan option to another? 894.507 Section 894.507 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL... change from one dental or vision plan or plan option to another? (a) You may change from one dental and...

  11. 5 CFR 894.507 - After I'm enrolled, may I change from one dental or vision plan or plan option to another?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... dental or vision plan or plan option to another? 894.507 Section 894.507 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL... change from one dental or vision plan or plan option to another? (a) You may change from one dental and...

  12. Genome sequence of Victivallis vadensis ATCC BAA-548, an anaerobic bacterium from the phylum Lentisphaerae, isolated from the human gastro-intestinal tract

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Van Passel, Mark W.J.; Kant, Ravi; Palva, Airi

    2011-01-01

    Victivallis vadensis ATCC BAA-548 represents the first cultured representative from the novel phylum Lentisphaerae, a deep-branching bacterial lineage. Few cultured bacteria from this phylum are known, and V. vadensis therefore represents an important organism for evolutionary studies. V. vadensis is a strictly anaerobic sugar-fermenting isolate from the human gastro-intestinal tract.

  13. Association between endothelial nitric oxide synthase (ENOS) G894T polymorphism and high altitude (HA) adaptation: a meta-analysis.

    PubMed

    Lu, Hong-xiang; Wang, Yu-xiao; Chen, Yu; Luo, Yong-jun

    2015-11-01

    Highland natives adapt well to the hypoxic environment at high altitude (HA). Several genes have been reported to be linked to HA adaptation. Previous studies showed that the endothelial ni- tric oxide synthase (ENOS) G894T polymorphism contributed to the physiology and pathophysiology of hu- mans at HA by regulating the production of NO. In this meta-analysis, we evaluate the association between the ENOS G894T polymorphism and HA adaptation through analyzing the published data. We searched all relevant literature about the ENOS G894T polymorphism and HA adaptation in PubMed, Med- line, and Embase before Step 2015. A random-effects model was applied (Revman 5.0), and study quality was assessed in duplicate. Six studies with 634 HA native cases and 621 low-altitude controls were included in this meta-analysis. From the results, we observed that the wild-type allele G was significantly overrepresented in the HA groups (OR = 1.85; 95% Cl, 1.47-2.33; P < 0.0001). In addition, the GG genotype was significantly associated with HA adaptation (OR = 1.99; 95% Cl, 1.54-2.57; P < 0.0001). Our results showed that in 894 G allele carriers, the GG genotype might be a beneficial factor for HA adaptation through enhancing the level of NO. However, more studies were needed to confirm our findings due to the limited sample size.

  14. [G894T (NOS3) and G1958A (MTHFD1) gene polymorphisms and risk of ischemic heart disease in Yucatan, Mexico].

    PubMed

    García-González, Igrid; Solís-Cárdenas, Alberto de Jesús; Flores-Ocampo, Jorge A; Alejos-Mex, Ricardo; Herrera-Sánchez, Luis Fernando; González-Herrera, Lizbeth Josefina

    2015-01-01

    Cardiovascular medicine is focused on the search for genetic risk markers with predictive and/or prognostic value. Among the genetic variants of interest are G894T endothelial nitric oxide synthase and G1958A methylenetetrahydrofolate dehydrogenase1 gene polymorphisms. The aim of this study was to determine the possible association between these polymorphisms and ischemic heart disease in patients from Southern of Mexico (Yucatán). Case-control study matched by age, sex and origin was designed. We studied 98 patients with coronary disease and 101 controls. Participants were evaluated for the usual risk factors. The polymorphisms were identified using the polymerase chain reaction/restriction fragment length polymorphism analysis. Informed consent was obtained from all participants. The G894T and G1958A polymorphisms were not associated with ischemic heart disease, however, the TT genotype (G894T) was associated with the angina (OR=10.2; 95%CI, 1.51-68.8; p=0.025). The genotype GT (G894T) was the most frequent in patients with family history of coronary artery disease. Multiple logistic regression analysis identified smoking (OR=5.21; 95%CI, 2.1-12.9; p=0.000), hypertension (OR=3.54; 95%CI, 1.47-8.56; p=0.005) and obesity (OR=1.16; 95%CI, 1.1-1.27; p=0.001) as risk factors predicting the ischemic heart disease. The G894T and G1958A polymorphisms showed not association with ischemic heart disease. However, homozygosis for the 894T allele (NOS3) confers at risk to develop angina on Yucatán. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  15. Pasteurization of milk: the heat inactivation kinetics of milk-borne dairy pathogens under commercial-type conditions of turbulent flow.

    PubMed

    Pearce, L E; Smythe, B W; Crawford, R A; Oakley, E; Hathaway, S C; Shepherd, J M

    2012-01-01

    This is the first study to report kinetic data on the survival of a range of significant milk-borne pathogens under commercial-type pasteurization conditions. The most heat-resistant strain of each of the milk-borne pathogens Staphylococcus aureus, Yersinia enterocolitica, pathogenic Escherichia coli, Cronobacter sakazakii (formerly known as Enterobacter sakazakii), Listeria monocytogenes, and Salmonella was selected to obtain the worst-case scenario in heat inactivation trials using a pilot-plant-scale pasteurizer. Initially, approximately 30 of each species were screened using a submerged coil unit. Then, UHT milk was inoculated with the most heat-resistant pathogens at ~10(7)/mL and heat treated in a pilot-plant-scale pasteurizer under commercial-type conditions of turbulent flow for 15s over a temperature range from 56 to 66°C and at 72°C. Survivors were enumerated on nonselective media chosen for the highest efficiency of plating of heat-damaged bacteria of each of the chosen strains. The mean log(10) reductions and temperatures of inactivation of the 6 pathogens during a 15-s treatment were Staph. aureus >6.7 at 66.5°C, Y. enterocolitica >6.8 at 62.5°C, pathogenic E. coli >6.8 at 65°C, C. sakazakii >6.7 at 67.5°C, L. monocytogenes >6.9 at 65.5°C, and Salmonella ser. Typhimurium >6.9 at 61.5°C. The kinetic data from these experiments will be used by the New Zealand Ministry of Agriculture and Forestry to populate the quantitative risk assessment model being developed to investigate the risks to New Zealand consumers from pasteurized, compared with nonpasteurized, milk and milk products. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. 5 CFR 894.509 - What are the QLEs that are consistent with increasing my type of enrollment?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Enrollment and Changing Enrollment § 894.509 What are the QLEs that are consistent with...

  17. 5 CFR 894.203 - If I have a self plus one enrollment, when may I change which family member I want to cover or...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false If I have a self plus one enrollment, when may I change which family member I want to cover or change to self only? 894.203 Section 894.203 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL...

  18. Tumor Necrosis Factor (TNF) –308G>A, Nitric Oxide Synthase 3 (NOS3) +894G>T Polymorphisms and Migraine Risk: A Meta-Analysis

    PubMed Central

    Chen, Min; Tang, Wenjing; Hou, Lei; Liu, Ruozhuo; Dong, Zhao; Han, Xun; Zhang, Xiaofei; Wan, Dongjun; Yu, Shengyuan

    2015-01-01

    Background and Objective Conflicting data have been reported on the association between tumor necrosis factor (TNF) –308G>A and nitric oxide synthase 3 (NOS3) +894G>T polymorphisms and migraine. We performed a meta-analysis of case-control studies to evaluate whether the TNF –308G>A and NOS3 +894G>T polymorphisms confer genetic susceptibility to migraine. Method We performed an updated meta-analysis for TNF –308G>A and a meta-analysis for NOS3 +894G>T based on studies published up to July 2014. We calculated study specific odds ratios (OR) and 95% confidence intervals (95% CI) assuming allele contrast, dominant model, recessive model, and co-dominant model as pooled effect estimates. Results Eleven studies in 6682 migraineurs and 22591 controls for TNF –308G>A and six studies in 1055 migraineurs and 877 controls for NOS3 +894G>T were included in the analysis. Neither indicated overall associations between gene polymorphisms and migraine risk. Subgroup analyses suggested that the “A” allele of the TNF –308G>A variant increases the risk of migraine among non-Caucasians (dominant model: pooled OR = 1.82; 95% CI 1.15 – 2.87). The risk of migraine with aura (MA) was increased among both Caucasians and non-Caucasians. Subgroup analyses suggested that the “T” allele of the NOS3 +894G>T variant increases the risk of migraine among non-Caucasians (co-dominant model: pooled OR = 2.10; 95% CI 1.14 – 3.88). Conclusions Our findings appear to support the hypothesis that the TNF –308G>A polymorphism may act as a genetic susceptibility factor for migraine among non-Caucasians and that the NOS3 +894G>T polymorphism may modulate the risk of migraine among non-Caucasians. PMID:26098763

  19. Inactivation of Cronobacter malonaticus cells and inhibition of its biofilm formation exposed to hydrogen peroxide stress.

    PubMed

    Ye, Yingwang; Zhang, Maofeng; Jiao, Rui; Ling, Na; Zhang, Xiyan; Tong, Liaowang; Zeng, Haiyang; Zhang, Jumei; Wu, Qingping

    2018-01-01

    Presence of Cronobacter malonaticus in powdered infant formula (PIF) poses a high risk to infant and public health. Cronobacter malonaticus has been widely distributed in food and food processing environments, and the true origin of C. malonaticus in PIF is poorly understood. Control and prevention of C. malonaticus is necessary for achieving microbial safety of PIF. However, little information about decontamination of C. malonaticus is available. In this study, effects of hydrogen peroxide on inactivation and morphological changes of C. malonaticus cells were determined. Furthermore, inhibitory effects of H 2 O 2 on biofilm formation in C. malonaticus were also performed. Results indicated that H 2 O 2 could completely inactivate C. malonaticus in sterile water with 0.06% H 2 O 2 for 25 min, 0.08% H 2 O 2 for 15 min, and 0.10% for 10 min, respectively, whereas the survival rates of C. malonaticus in tryptic soy broth medium significantly increased with the same treatment time and concentration of H 2 O 2 . In addition, morphological changes of C. malonaticus cells, including cell shrinkage, disruption of cells, cell intercession, and leakage of intercellular material in sterile water after H 2 O 2 treatment, were more predominant than those in tryptic soy broth. Finally, significant reduction in biofilm formation by H 2 O 2 was found using crystal violet staining, scanning electron microscopy, and confocal laser scanning microscopy detection compared with control samples. This is the first report to determine the effects of H 2 O 2 on C. malonaticus cells and biofilm formation. The findings provided valuable information for practical application of H 2 O 2 for decontamination of C. malonaticus in dairy processing. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Structural mechanisms of DNA binding and unwinding in bacterial RecQ helicases

    DOE PAGES

    Manthei, Kelly A.; Hill, Morgan C.; Burke, Jordan E.; ...

    2015-03-23

    RecQ helicases unwind remarkably diverse DNA structures as key components of many cellular processes. How RecQ enzymes accommodate different substrates in a unified mechanism that couples ATP hydrolysis to DNA unwinding is unknown. In this paper, the X-ray crystal structure of the Cronobacter sakazakii RecQ catalytic core domain bound to duplex DNA with a 3' single-stranded extension identifies two DNA-dependent conformational rearrangements: a winged-helix domain pivots ~90° to close onto duplex DNA, and a conserved aromatic-rich loop is remodeled to bind ssDNA. These changes coincide with a restructuring of the RecQ ATPase active site that positions catalytic residues for ATPmore » hydrolysis. Complex formation also induces a tight bend in the DNA and melts a portion of the duplex. Finally, this bending, coupled with translocation, could provide RecQ with a mechanism for unwinding duplex and other DNA structures.« less

  1. Associations of the eNOS G894T gene polymorphism with target organ damage in children with newly diagnosed primary hypertension.

    PubMed

    Śladowska-Kozłowska, Joanna; Litwin, Mieczysław; Niemirska, Anna; Wierzbicka, Aldona; Roszczynko, Marta; Szperl, Małgorzata

    2015-12-01

    The endothelial nitric oxide synthase (eNOS) G894T gene polymorphism is associated with the risk of primary hypertension (PH) and vascular complications in adults with PH. We explored the associations of the G894T polymorphism with 24-h ambulatory blood pressure, left ventricular mass (LVM), carotid intima media thickness (cIMT), urinary albumin excretion, oxidative stress and inflammatory parameters in 126 children with newly diagnosed PH and in 83 healthy children. Among the 126 children with PH 92 (73%) had ambulatory hypertension and 34 (27%) had severe ambulatory hypertension. Left ventricular hypertrophy (LVH) was detected in 39 (31%) patients, cIMT of >2 standard deviation scores in 21 (16.6%) patients, albuminuria of >30 mg/24 h in 18 (14.3%) patients and metabolic syndrome (MS) in 22 (17.5%) patients. The frequency of the T allele was 52.4% in the PH group and 54.2% in the control group (not significant), and in both groups the frequency of the T allele was consistent with the Hardy-Weinberg equilibrium. Compared with G allele carriers, hypertensive T allele carriers had increased cIMT (p < 0.05) and more severe albuminuria (not significant, p = 0.1); there was no difference between the groups in hypertension severity and LVM. T and G allele distribution did not differ between patients with and without metabolic syndrome. No significant correlations between the assessed parameters and the eNOS G894T gene polymorphism were found in the controls, although T allele carriers tended to have an increased cIMT (p = 0.09). The eNOS T allele is not more prevalent among hypertensive children than among healthy ones, but it is associated with early vascular damage in children with PH, independent of metabolic abnormalities. No associations between the eNOS G894T polymorphism and metabolic abnormalities were found.

  2. [Detection of biofilm formation by selected pathogens relevant to the food industry].

    PubMed

    Šilhová-Hrušková, L; Moťková, P; Šilha, D; Vytřasová, J

    2015-09-01

    Detection of biofilm formation by microbial pathogens relevant to the food industry and comparison of biofilm formation under different conditions of culture. The following microorganisms were selected for the study: Staphylococcus aureus, Listeria innocua, Listeria ivanovii, Cronobacter sakazakii, Cronobacter muytjensii, Arcobacter butzleri, Arcobacter cryaerophilus, Campylobacter jejuni, and Campylobacter coli. To detect biofilm formation the microtiter plate assay, as described by Christensen and culture on stainless steel coupons were used. The biofilm forming capacity was confirmed in all microorganisms tested, both on the microtiter plates and stainless steel coupons. Biofilm formation was influenced by the culture medium, material used, and culture duration as well as by the test microorganism. It was found that different species and strains of the same genus differ in biofilm formation. Differences were also found between the collection strains and isolates from the environment. Some bacteria tended to form biofilm more readily on the surface of the polyethylene microtiter plates and less readily on stainless steel coupons while others appeared to have an opposite tendency. Some pathogens were able to increase the planktonic cell density in the initial suspension even by three orders of magnitude within 72 hours while producing plenty of biofilm. The study of biofilm formation by high risk pathogens is of utmost importance, not only to the food industry. From the obtained results, it is evident that bacterial biofilms form rapidly (within 24 hours in the present study). Due to their architecture, these biofilms are difficult to eradicate, and therefore, it is crucial to prevent biofilm formation.

  3. Kinetic study of alkaline protease 894 for the hydrolysis of the pearl oyster Pinctada martensii

    NASA Astrophysics Data System (ADS)

    Chen, Xin; Chen, Hua; Cai, Bingna; Liu, Qingqin; Sun, Huili

    2013-05-01

    A new enzyme (alkaline protease 894) obtained from the marine extremophile Flavobacterium yellowsea (YS-80-122) has exhibited strong substrate-binding and catalytic activity, even at low temperature, but the characteristics of the hydrolysis with this enzyme are still unclear. The pearl oyster Pinctada martensii was used in this study as the raw material to illustrate the kinetic properties of protease 894. After investigating the intrinsic relationship between the degree of hydrolysis and several factors, including initial reaction pH, temperature, substrate concentration, enzyme concentration, and hydrolysis time, the kinetics model was established. This study showed that the optimal conditions for the enzymatic hydrolysis were an initial reaction pH of 5.0, temperature of 30°C, substrate concentration of 10% (w/v), enzyme concentration of 2 500 U/g, and hydrolysis time of 160 min. The kinetic characteristics of the protease for the hydrolysis of P. martensii were obtained. The inactivation constant was found to be 15.16/min, and the average relative error between the derived kinetics model and the actual measurement was only 3.04%, which indicated a high degree of fitness. Therefore, this study provides a basis for the investigation of the concrete kinetic characteristics of the new protease, which has potential applications in the food industry.

  4. 5 CFR 894.102 - If I have a pre-existing dental or vision condition, may I join FEDVIP?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false If I have a pre-existing dental or vision... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.102 If I have a pre-existing dental or vision...

  5. 5 CFR 894.102 - If I have a pre-existing dental or vision condition, may I join FEDVIP?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false If I have a pre-existing dental or vision... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.102 If I have a pre-existing dental or vision...

  6. 5 CFR 894.102 - If I have a pre-existing dental or vision condition, may I join FEDVIP?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false If I have a pre-existing dental or vision... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.102 If I have a pre-existing dental or vision...

  7. 5 CFR 894.102 - If I have a pre-existing dental or vision condition, may I join FEDVIP?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false If I have a pre-existing dental or vision... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.102 If I have a pre-existing dental or vision...

  8. 5 CFR 894.102 - If I have a pre-existing dental or vision condition, may I join FEDVIP?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false If I have a pre-existing dental or vision... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Administration and General Provisions § 894.102 If I have a pre-existing dental or vision...

  9. [Meta-analysis on the association of G894T polymorphism in endothelial nitric oxide synthase gene and essential hypertension in Chinese population].

    PubMed

    Wang, Cong-Ju; Zhao, Jing-Bo; Xu, Jia-Liang; Xiang, Ze-Lin; Liang, Chang-Wei; Li, Jie

    2009-08-01

    To evaluate the relationship between G894T (Glu298Asp) polymorphism in the endothelial nitric oxide synthase (eNOS) gene and essential hypertension in Chinese population from different regions. Odds ratios (ORs) of G894T genotype and allele distributions in essential hypertension patients against healthy controls were analyzed. All the relevant studies were screened with poor-qualified studies eliminated. Meta-analysis software MIX (Meta-analysis with interactive explanations-version 1.71), was applied for investigating and analyzing heterogeneity among individual studies and summarizing the effects across studies, and the risk of publication bias was evaluated. A total of 1900 cases and 1216 controls from 10 studies were included. The heterogeneity between studies was significant (P = 0.013; P = 0.011) and there were substantial sources of publication bias (P = 0.049; P = 0.038). The pooled OR (with 95%CI) of GT + TT vs. GG genotype was 1.79 (1.33 - 2.42) (Z = 3.83, P < 0.001), and the pooled OR (with 95%CI) of T vs. G allele was 1.73 (1.32 - 2.27) (Z = 3.92, P < 0.001). In Chinese population, mainly the Hans ethnic group, 894G-->T mutation in the eNOS appeared to be related to essential hypertension.

  10. Heart failure and endothelial nitric oxide synthase G894T gene polymorphism frequency variations within ancestries.

    PubMed

    Oliveira, Romulo V M; Albuquerque, Felipe N; Duque, Gustavo S; Freitas, Rossana G A; Carvalho, Elizeu F; Brandão, Andrea A; Silva, Dayse A; Mourilhe-Rocha, Ricardo; Albuquerque, Denilson C

    2018-02-28

    The G894T polymorphism in endothelial nitric oxide synthase enzyme gene plays an important role in heart failure (HF) and its frequency varies among populations. We investigated this association in highly admixed samples in terms of ancestry. The cohort included 210 HF patients and 106 healthy individuals. Self-reported race and NYHA class were analyzed for HF patients. G894T polymorphism was analyzed by polymerase chain reaction (PCR) and by restriction fragment length polymorphism technique. Ancestry was estimated using a PCR reaction containing 46 autosomal ancestry informative markers and an analysis by capillary electrophoresis. The GG homozygous genotype had a higher frequency in HF patients (63.8%) than in healthy individuals (48.1%), showing an increased chance (odds ratio 1.90, 95% confidence interval 1.18-3.05). The ancestry profiles in patients and controls were similar, with a major European contribution (57.1% and 63.2%), followed by African (30.2% and 24.0%) and Native American (12.7% and 12.8%), without a significant difference between both samples (p = 0.28). The GG genotype is associated to HF prognosis, and this association remains present in highly admixed sample groups. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Transcriptome Sequence and Plasmid Copy Number Analysis of the Brewery Isolate Pediococcus claussenii ATCC BAA-344T during Growth in Beer

    PubMed Central

    Pittet, Vanessa; Phister, Trevor G.; Ziola, Barry

    2013-01-01

    Growth of specific lactic acid bacteria in beer leads to spoiled product and economic loss for the brewing industry. Microbial growth is typically inhibited by the combined stresses found in beer (e.g., ethanol, hops, low pH, minimal nutrients); however, certain bacteria have adapted to grow in this harsh environment. Considering little is known about the mechanisms used by bacteria to grow in and spoil beer, transcriptome sequencing was performed on a variant of the beer-spoilage organism Pediococcus claussenii ATCC BAA-344T (Pc344-358). Illumina sequencing was used to compare the transcript levels in Pc344-358 growing mid-exponentially in beer to those in nutrient-rich MRS broth. Various operons demonstrated high gene expression in beer, several of which are involved in nutrient acquisition and overcoming the inhibitory effects of hop compounds. As well, genes functioning in cell membrane modification and biosynthesis demonstrated significantly higher transcript levels in Pc344-358 growing in beer. Three plasmids had the majority of their genes showing increased transcript levels in beer, whereas the two cryptic plasmids showed slightly decreased gene expression. Follow-up analysis of plasmid copy number in both growth environments revealed similar trends, where more copies of the three non-cryptic plasmids were found in Pc344-358 growing in beer. Transcriptome sequencing also enabled the addition of several genes to the P . claussenii ATCC BAA-344T genome annotation, some of which are putatively transcribed as non-coding RNAs. The sequencing results not only provide the first transcriptome description of a beer-spoilage organism while growing in beer, but they also highlight several targets for future exploration, including genes that may have a role in the general stress response of lactic acid bacteria. PMID:24040005

  12. Plant growth promoting potential and phylogenetic characteristics of a lichenized nitrogen fixing bacterium, Enterobacter cloacae.

    PubMed

    Swamy, Chidanandamurthy Thippeswamy; Gayathri, Devaraja; Devaraja, Thimmalapura Neelakantaiah; Bandekar, Mandar; D'Souza, Stecy Elvira; Meena, Ram Murti; Ramaiah, Nagappa

    2016-12-01

    Lichens are complex symbiotic association of mycobionts, photobionts, and bacteriobionts, including chemolithotropic bacteria. In the present study, 46 lichenized bacteria were isolated by conventional and enrichment culture methods on nitrogen-free bromothymol blue (NFb) medium. Only 11 of the 46 isolates fixed nitrogen on NFb and had reduced acetylene. All these 11 isolates had also produced siderophore and 10 of them the IAA. Further, ammonia production was recorded from nine of these nitrogen fixers (NF). On molecular characterization, 16 S rRNA sequencing recorded that, nine NF belonged to Proteobacteria, within Gammaproteobacteria, and were closely related to Enterobacter sp. with a maximum similarity to Enterobacter cloacae. Each one of our NF isolates was aligned closely to Enterobacter pulveris strain E443, Cronobacter sakazakii strain PNP8 and Providencia rettgeri strain ALK058. Notably, a few strains we examined found to possess plant growth promoting properties. This is the first report of Enterobacter sp. from lichens which may be inhabit lichen thalli extrinsically or intrinsically. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Production of the antimicrobial peptides Caseicin A and B by Bacillus isolates growing on sodium caseinate.

    PubMed

    Kent, R M; Guinane, C M; O'Connor, P M; Fitzgerald, G F; Hill, C; Stanton, C; Ross, R P

    2012-08-01

    The aim of this study was to identify Bacillus isolates capable of degrading sodium caseinate and subsequently to generate bioactive peptides with antimicrobial activity. Sodium caseinate (2.5% w/v) was inoculated separately with 16 Bacillus isolates and allowed to ferment overnight. Protein breakdown in the fermentates was analysed using gel permeation-HPLC (GP-HPLC) and screened for peptides (<3-kDa) with MALDI-TOF mass spectrometry. Caseicin A (IKHQGLPQE) and caseicin B (VLNENLLR), two previously characterized antimicrobial peptides, were identified in the fermentates of both Bacillus cereus and Bacillus thuringiensis isolates. The caseicin peptides were subsequently purified by RP-HPLC and antimicrobial assays indicated that the peptides maintained the previously identified inhibitory activity against the infant formula pathogen Cronobacter sakazakii. We report a new method using Bacillus sp. to generate two previously characterized antimicrobial peptides from casein. This study highlights the potential to exploit Bacillus sp. or the enzymes they produce for the generation of bioactive antimicrobial peptides from bovine casein. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

  14. Effect of gamma irradiation on microbial quality of minimally processed carrot and lettuce: A case study in Greater Accra region of Ghana

    NASA Astrophysics Data System (ADS)

    Frimpong, G. K.; Kottoh, I. D.; Ofosu, D. O.; Larbi, D.

    2015-05-01

    The effect of ionizing radiation on the microbiological quality on minimally processed carrot and lettuce was studied. The aim was to investigate the effect of irradiation as a sanitizing agent on the bacteriological quality of some raw eaten salad vegetables obtained from retailers in Accra, Ghana. Minimally processed carrot and lettuce were analysed for total viable count, total coliform count and pathogenic organisms. The samples collected were treated and analysed for a 15 day period. The total viable count for carrot ranged from 1.49 to 14.01 log10 cfu/10 g while that of lettuce was 0.70 to 8.5 7 log10 cfu/10 g. It was also observed that total coliform count for carrot was 1.46-7.53 log10 cfu/10 g and 0.14-7.35 log10 cfu/10 g for lettuce. The predominant pathogenic organisms identified were Bacillus cereus, Cronobacter sakazakii, Staphylococcus aureus, and Klebsiella spp. It was concluded that 2 kGy was most effective for medium dose treatment of minimally processed carrot and lettuce.

  15. 5 CFR 894.204 - May I be enrolled in more than one dental or vision plan at a time?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false May I be enrolled in more than one dental... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and Types of Enrollment § 894.204 May I be enrolled in more than one dental or vision...

  16. 5 CFR 894.204 - May I be enrolled in more than one dental or vision plan at a time?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false May I be enrolled in more than one dental... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and Types of Enrollment § 894.204 May I be enrolled in more than one dental or vision...

  17. 5 CFR 894.204 - May I be enrolled in more than one dental or vision plan at a time?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false May I be enrolled in more than one dental... MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES DENTAL AND VISION INSURANCE PROGRAM Coverage and Types of Enrollment § 894.204 May I be enrolled in more than one dental or vision...

  18. 5 CFR 894.405 - What happens if I go into nonpay status or if my pay/annuity is insufficient to cover the...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.405 What happens if I go into nonpay status or... is too low to cover the premium allotments, or if you go into a nonpay status, contact the...

  19. 5 CFR 894.405 - What happens if I go into nonpay status or if my pay/annuity is insufficient to cover the...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.405 What happens if I go into nonpay status or... is too low to cover the premium allotments, or if you go into a nonpay status, contact the...

  20. 5 CFR 894.405 - What happens if I go into nonpay status or if my pay/annuity is insufficient to cover the...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.405 What happens if I go into nonpay status or... is too low to cover the premium allotments, or if you go into a nonpay status, contact the...

  1. 5 CFR 894.405 - What happens if I go into nonpay status or if my pay/annuity is insufficient to cover the...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.405 What happens if I go into nonpay status or... is too low to cover the premium allotments, or if you go into a nonpay status, contact the...

  2. 5 CFR 894.405 - What happens if I go into nonpay status or if my pay/annuity is insufficient to cover the...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... DENTAL AND VISION INSURANCE PROGRAM Cost of Coverage § 894.405 What happens if I go into nonpay status or... is too low to cover the premium allotments, or if you go into a nonpay status, contact the...

  3. Isolation of Enterobacter sakazakii from ass' milk in Sicily: case report, safety and legal issues.

    PubMed

    Conte, F; Passantino, A

    2008-07-01

    Enterobacter sakazakii (Es) infections are likely to involve newborns and infants, causing meningitis and necrotizing enterocolitis and sepsis. Contamination of infant formulae milk during factory production or bottle preparation is implicated. Es has been isolated from environmental sources and from food other than infant formula and milk powder, but why it is associated only with the consumption of infant formulae, is unclear. According to Regulation (EC) No. 2073/2005 on the microbiological criteria for foodstuffs, Es is considered a microorganisms of greatest concern in infant formulae and follow-on formulae. Es is included between "safety criteria". The isolation of two strains of Es from 50 samples of ass' milk in Sicily is described. The antibiotic resistance profile of the isolates revealed a multiple resistance profile, including fluoroquinolones, commonly used to treat the infections. The authors underline the importance of survey because in Italy ass' milk is considered one of the solutions for infants suffering from hypersensitivity to milk protein of some animal species. There is scarce information about the ecology and the uncertainty concerning the source of infection in the children and adults; the authors are concerned that ass' milk could become a high-risk food.

  4. 5 CFR 894.701 - May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false May I keep my dental and/or vision... DENTAL AND VISION INSURANCE PROGRAM Annuitants and Compensationers § 894.701 May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation? (a) Your FEDVIP coverage...

  5. 5 CFR 894.701 - May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false May I keep my dental and/or vision... DENTAL AND VISION INSURANCE PROGRAM Annuitants and Compensationers § 894.701 May I keep my dental and/or vision coverage when I retire or start receiving workers' compensation? (a) Your FEDVIP coverage...

  6. Surface-enhanced Raman spectroscopy introduced into the International Standard Organization (ISO) regulations as an alternative method for detection and identification of pathogens in the food industry.

    PubMed

    Witkowska, Evelin; Korsak, Dorota; Kowalska, Aneta; Księżopolska-Gocalska, Monika; Niedziółka-Jönsson, Joanna; Roźniecka, Ewa; Michałowicz, Weronika; Albrycht, Paweł; Podrażka, Marta; Hołyst, Robert; Waluk, Jacek; Kamińska, Agnieszka

    2017-02-01

    We show that surface-enhanced Raman spectroscopy (SERS) coupled with principal component analysis (PCA) can serve as a fast, reliable, and easy method for detection and identification of food-borne bacteria, namely Salmonella spp., Listeria monocytogenes, and Cronobacter spp., in different types of food matrices (salmon, eggs, powdered infant formula milk, mixed herbs, respectively). The main aim of this work was to introduce the SERS technique into three ISO (6579:2002; 11290-1:1996/A1:2004; 22964:2006) standard procedures required for detection of these bacteria in food. Our study demonstrates that the SERS technique is effective in distinguishing very closely related bacteria within a genus grown on solid and liquid media. The advantages of the proposed ISO-SERS method for bacteria identification include simplicity and reduced time of analysis, from almost 144 h required by standard methods to 48 h for the SERS-based approach. Additionally, PCA allows one to perform statistical classification of studied bacteria and to identify the spectrum of an unknown sample. Calculated first and second principal components (PC-1, PC-2) account for 96, 98, and 90% of total variance in the spectra and enable one to identify the Salmonella spp., L. monocytogenes, and Cronobacter spp., respectively. Moreover, the presented study demonstrates the excellent possibility for simultaneous detection of analyzed food-borne bacteria in one sample test (98% of PC-1 and PC-2) with a goal of splitting the data set into three separated clusters corresponding to the three studied bacteria species. The studies described in this paper suggest that SERS represents an alternative to standard microorganism diagnostic procedures. Graphical Abstract New approach of the SERS strategy for detection and identification of food-borne bacteria, namely S. enterica, L. monocytogenes, and C. sakazakii in selected food matrices.

  7. Bioengineered Nisin A Derivatives with Enhanced Activity against Both Gram Positive and Gram Negative Pathogens

    PubMed Central

    Field, Des; Begley, Maire; O’Connor, Paula M.; Daly, Karen M.; Hugenholtz, Floor; Cotter, Paul D.; Hill, Colin; Ross, R. Paul

    2012-01-01

    Nisin is a bacteriocin widely utilized in more than 50 countries as a safe and natural antibacterial food preservative. It is the most extensively studied bacteriocin, having undergone decades of bioengineering with a view to improving function and physicochemical properties. The discovery of novel nisin variants with enhanced activity against clinical and foodborne pathogens has recently been described. We screened a randomized bank of nisin A producers and identified a variant with a serine to glycine change at position 29 (S29G), with enhanced efficacy against S. aureus SA113. Using a site-saturation mutagenesis approach we generated three more derivatives (S29A, S29D and S29E) with enhanced activity against a range of Gram positive drug resistant clinical, veterinary and food pathogens. In addition, a number of the nisin S29 derivatives displayed superior antimicrobial activity to nisin A when assessed against a range of Gram negative food-associated pathogens, including E. coli, Salmonella enterica serovar Typhimurium and Cronobacter sakazakii. This is the first report of derivatives of nisin, or indeed any lantibiotic, with enhanced antimicrobial activity against both Gram positive and Gram negative bacteria. PMID:23056510

  8. Recovery Estimation of Dried Foodborne Pathogens Is Directly Related to Rehydration Kinetics

    PubMed Central

    Lang, Emilie; Zoz, Fiona; Iaconelli, Cyril; Guyot, Stéphane; Alvarez-Martin, Pablo; Beney, Laurent; Perrier-Cornet, Jean-Marie; Gervais, Patrick

    2016-01-01

    Drying is a common process which is used to preserve food products and technological microorganisms, but which is deleterious for the cells. The aim of this study is to differentiate the effects of drying alone from the effects of the successive and necessary rehydration. Rehydration of dried bacteria is a critical step already studied in starter culture but not for different kinetics and not for pathogens. In the present study, the influence of rehydration kinetics was investigated for three foodborne pathogens involved in neonatal diseases caused by the consumption of rehydrated milk powder: Salmonella enterica subsp. enterica serovar Typhimurium, Salmonella enterica subsp. enterica serovar Senftenberg and Cronobacter sakazakii. Bacteria were dried in controlled relative humidity atmospheres and then rehydrated using different methods. Our results showed that the survival of the three pathogens was strongly related to rehydration kinetics. Consequently, rehydration is an important step to consider during food safety assessment or during studies of dried foodborne pathogens. Also, it has to be considered with more attention in consumers’ homes during the preparation of food, like powdered infant formula, to avoid pathogens recovery. PMID:27494169

  9. Thousands of Stellar SiO masers in the Galactic center: The Bulge Asymmetries and Dynamic Evolution (BAaDE) survey

    NASA Astrophysics Data System (ADS)

    Sjouwerman, Loránt O.; Pihlström, Ylva M.; Rich, R. Michael; Morris, Mark R.; Claussen, Mark J.

    2017-01-01

    A radio survey of red giant SiO sources in the inner Galaxy and bulge is not hindered by extinction. Accurate stellar velocities (<1 km/s) are obtained with minimal observing time (<1 min) per source. Detecting over 20,000 SiO maser sources yields data comparable to optical surveys with the additional strength of a much more thorough coverage of the highly obscured inner Galaxy. Modeling of such a large sample would reveal dynamical structures and minority populations; the velocity structure can be compared to kinematic structures seen in molecular gas, complex orbit structure in the bar, or stellar streams resulting from recently infallen systems. Our Bulge Asymmetries and Dynamic Evolution (BAaDE) survey yields bright SiO masers suitable for follow-up Galactic orbit and parallax determination using VLBI. Here we outline our early VLA observations at 43 GHz in the northern bulge and Galactic plane (0

  10. The 894G>T endothelial nitric oxide synthase genetic polymorphism affects hemodynamic responses to mental stress performed before and after exercise.

    PubMed

    Rocha, Natália Galito; Neves, Fabricia Junqueira; Silva, Bruno Moreira; Sales, Allan Robson Kluser; Nóbrega, Antonio Claudio

    2012-03-01

    Nitric oxide is the primary mediator of vasodilation during mental stress. Since genetic polymorphisms in the nitric oxide synthase (eNOS) gene seem to impair the production of NO, this study aimed to evaluate the effect of an exercise bout on hemodynamic responses to mental stress in subjects with the 894G>T polymorphism of eNOS. Subjects without (wild-type group; n = 16) or with (polymorphic-type group; n = 19) the 894G>T polymorphism underwent a mental stress challenge before and after a maximal cardiopulmonary exercise test. Blood pressure was measured by auscultation and forearm blood flow by venous occlusion plethysmography. The groups were similar regarding anthropometric, metabolic, resting blood pressure and exercise variables. Before exercise, systolic blood pressure response during mental stress was higher in the polymorphic-type group (∆wild-type: 8.0 ± 2.0% vs. ∆polymorphic-type: 12.5 ± 1.8%, P = 0.01), while the increase in forearm vascular conductance was similar between the groups (∆wild-type 90.8 ± 26.4% vs. ∆polymorphic-type: 86.3 ± 24.1%, P = 0.44). After exercise, the systolic blood pressure at baseline and during mental stress was lower than before exercise in the whole group (P < 0.05), but the pressure response during mental stress was still higher in the polymorphic-type group (∆wild-type: 5.8 ± 1.5% vs. ∆polymorphic-type: 10.2 ± 1.4%, P = 0.01). The increase in forearm vascular conductance was inhibited only in the polymorphic-type group (∆before exercise 86.3 ± 24.1% vs. ∆after exercise: 41.5 ± 12.6%, P = 0.04). In conclusion, these results suggest the 894G>T eNOS polymorphism is associated with altered hemodynamic responses to mental stress both before and after a single bout of dynamic exercise with potential clinical implications.

  11. Association of G894T eNOS, 4G/5G PAI and T1131C APOA5 polymorphisms with susceptibility to myocardial infarction in Morocco.

    PubMed

    Hassani Idrissi, Hind; Hmimech, Wiam; Diakite, Brehima; Korchi, Farah; Baghdadi, Dalila; Habbal, Rachida; Nadifi, Sellama

    2016-09-01

    Myocardial infarction (MI) is a common multifactorial disease. Numerous studies have found that genetic plays an essential role in MI occurrence. The main objective of our case-control study is to explore the association of G894T eNOS (rs1799983), 4G/5G PAI (rs1799889) and T1131C APOA5 (rs662799) polymorphisms with MI susceptibility in the Moroccan population. 118 MI patients were recruited vs 184 healthy controls. DNA samples were genotyped by PCR-RFLP method using MboI, BslI and MseI restriction enzymes respectively for the G894T eNOS, 4G/5G PAI and T1131C APOA5 polymorphisms. Our results show that the G894T eNOS was significantly associated with increased risk of MI under the three genetic transmission models (dominant: OR = 1.64, 95% CI = 1.05-2.58, P = 0.003; recessive: OR = 2.15, 95% CI = 0.74-6.16, P = 0.03; additive: OR = 1.54, 95% CI = 1.06-2.23, P = 0.001). The T1131C APOA5 polymorphism was associated to MI risk in recessive and additive models (OR = 1.53, 95% CI = 0.72-3.2, P = 0.04 and OR = 1.78, 95% CI = 1.26-2.51, P = 0.03 respectively). For the 4G/5G PAI variant, even the cases and controls groups were not in Hardy-Weinberg Equilibrium (HWE), the dominant and additive models show a statistically significant association with MI risk (OR = 7.96, 95%CI = 3.83-16.36, P = 0.01 and OR = 1.96, 95% CI = 1.4-2.72, P = 0.03 respectively). Our results suggest that G894T eNOS and T1131C APOA5 polymorphisms may be considered as genetic markers of MI among the Moroccan population. Further studies including larger sample sizes and exploring more genetic associations are needed to confirm our results and to better understand the susceptibility to MI.

  12. Association of endothelial nitric oxide synthase gene variants (-786 T>C, intron 4 b/a VNTR and 894 G>T) with idiopathic recurrent pregnancy loss: A case-control study with haplotype and in silico analysis.

    PubMed

    Azani, Alireza; Hosseinzadeh, Asghar; Azadkhah, Roya; Zonouzi, Ali Akbar Poursadegh; Zonouzi, Ahmad Poursadegh; Aftabi, Younes; Khani, Hourieh; Heidary, Leida; Danaii, Shahla; Bargahi, Nasrin; Pouladi, Nasser; Hosseini, Sayed Mostafa

    2017-08-01

    Many lines of evidence suggest that reduced production of nitric oxide (NO) due to single nucleotide polymorphisms in endothelial nitric oxide synthase (eNOS) gene may affect the implantation and maintenance of pregnancy. Accordingly, our objective was to investigate whether the eNOS polymorphisms (-786 T>C, intron 4 b/a VNTR and 894 G>T) and haplotypes may be associated with increased susceptibility to recurrent pregnancy loss (RPL). A total of 130 women with a history of two or more unexplained consecutive first trimester miscarriages and 110 ethnically matched women with at least two normal pregnancies and no history of pregnancy loss were included in the study as cases and controls, respectively. To identify the genotypes, we used polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP) methods In addition, an in silico analysis was conducted to predict the possible effects of the eNOS 894 G>T polymorphism on the structure and function of eNOS mRNA and protein using prediction servers. Our findings revealed that the prevalence of eNOS -786 T>C polymorphism, eNOS -786C allele and TC+CC genotype in cases were significantly higher than those in healthy controls (p<0.05). Also, the combination genotypes -786TT/4b4a and -786TT/894GG were significantly associated with reduced risk of RPL. We also found that the C-4a-G haplotype of the eNOS gene studied polymorphisms was significantly associated with a predisposition to RPL (odds ratio, 3.219; 95% confidence interval, 1.649-6.282; p=0.0003). The in silico analysis showed that the eNOS 894 G>T polymorphism couldn't affects eNOS mRNA and protein significantly. Our findings provide evidence to support the hypothesis that eNOS -786 T>C polymorphism and the -786C-4a-894G haplotype are associated with the high risk of RPL. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Estimation of Microbial Concentration in Food Products from Qualitative, Microbiological Test Data with the MPN Technique.

    PubMed

    Fujikawa, Hiroshi

    2017-01-01

    Microbial concentration in samples of a food product lot has been generally assumed to follow the log-normal distribution in food sampling, but this distribution cannot accommodate the concentration of zero. In the present study, first, a probabilistic study with the most probable number (MPN) technique was done for a target microbe present at a low (or zero) concentration in food products. Namely, based on the number of target pathogen-positive samples in the total samples of a product found by a qualitative, microbiological examination, the concentration of the pathogen in the product was estimated by means of the MPN technique. The effects of the sample size and the total sample number of a product were then examined. Second, operating characteristic (OC) curves for the concentration of a target microbe in a product lot were generated on the assumption that the concentration of a target microbe could be expressed with the Poisson distribution. OC curves for Salmonella and Cronobacter sakazakii in powdered formulae for infants and young children were successfully generated. The present study suggested that the MPN technique and the Poisson distribution would be useful for qualitative microbiological test data analysis for a target microbe whose concentration in a lot is expected to be low.

  14. Hygienic characteristics and microbiological hazard identification in horse and donkey raw milk.

    PubMed

    Colavita, Giampaolo; Amadoro, Carmela; Rossi, Franca; Fantuz, Francesco; Salimei, Elisabetta

    2016-01-01

    Today the interest toward horse (Equus caballus) and donkey (Equus asinus) milk for human consumption is receiving a renewed attention because of its particular composition, hypoallergenicity, and nutraceutical properties. The realistic perspective of global use of this aliment in balanced diets, especially for infancy and geriatrics, poses the need for a more in depth knowledge on milk hygiene and on the health status of dairy animals, as a prerequisite of consumers' safety. The aim of this paper was to review the available literature on the health and hygiene parameters as well as on the potential microbiological hazards in horse and donkey milk and the risks related to their consumption. Both microbial contamination and somatic cell count are reasonably low in equine milk and also the presence of pathogens, like Escherichia coli O157, Salmonella spp., Campylobacter spp., Yersinia enterocolitica, Brucella spp., Mycobacterium spp., Bacillus cereus, Cronobacter sakazakii, Streptococcus equi subsp. zooepidemicus, Rhodococcus equi, Streptococcus dysgalactiae subsp. equisimilis, Clostridium difficile and Burkholderia mallei is low. However, in those regions of the world where the prevalence of Brucella spp. and Rhodococcus equi is high, the alimentary risks could increase. Similarly, in areas with higher incidence of immunocompromised people, the increased risks should be warned not only for pathogens but also for opportunistic microbiota.

  15. Re-examination of the taxonomic status of Enterobacter helveticus, Enterobacter pulveris and Enterobacter turicensis as members of the genus Cronobacter and their reclassification in the genera Franconibacter gen. nov. and Siccibacter gen. nov. as Franconibacter helveticus comb. nov., Franconibacter pulveris comb. nov. and Siccibacter turicensis comb. nov., respectively.

    PubMed

    Stephan, Roger; Grim, Christopher J; Gopinath, Gopal R; Mammel, Mark K; Sathyamoorthy, Venugopal; Trach, Larisa H; Chase, Hannah R; Fanning, Séamus; Tall, Ben D

    2014-10-01

    Recently, a taxonomical re-evaluation of the genus Enterobacter, based on multi-locus sequence typing (MLST) analysis, has led to the proposal that the species Enterobacter pulveris, Enterobacter helveticus and Enterobacter turicensis should be reclassified as novel species of the genus Cronobacter. In the present work, new genome-scale analyses, including average nucleotide identity, genome-scale phylogeny and k-mer analysis, coupled with previously reported DNA-DNA hybridization values and biochemical characterization strongly indicate that these three species of the genus Enterobacter are not members of the genus Cronobacter, nor do they belong to the re-evaluated genus Enterobacter. Furthermore, data from this polyphasic study indicated that all three species constitute two new genera. We propose reclassifying Enterobacter pulveris and Enterobacter helveticus in the genus Franconibacter gen. nov. as Franconibacter pulveris comb. nov. (type strain 601/05(T) = LMG 24057(T) = DSM 19144(T)) and Franconibacter helveticus comb. nov. (type strain 513/05(T) = LMG 23732(T) = DSM 18396(T)), respectively, and Enterobacter turicensis in the genus Siccibacter gen. nov. as Siccibacter turicensis comb. nov. (type strain 508/05(T) = LMG 23730(T) = DSM 18397(T)).

  16. Re-examination of the taxonomic status of Enterobacter helveticus, Enterobacter pulveris and Enterobacter turicensis as members of the genus Cronobacter and their reclassification in the genera Franconibacter gen. nov. and Siccibacter gen. nov. as Franconibacter helveticus comb. nov., Franconibacter pulveris comb. nov. and Siccibacter turicensis comb. nov., respectively

    PubMed Central

    Grim, Christopher J.; Gopinath, Gopal R.; Mammel, Mark K.; Sathyamoorthy, Venugopal; Trach, Larisa H.; Chase, Hannah R.; Fanning, Séamus; Tall, Ben D.

    2014-01-01

    Recently, a taxonomical re-evaluation of the genus Enterobacter, based on multi-locus sequence typing (MLST) analysis, has led to the proposal that the species Enterobacter pulveris, Enterobacter helveticus and Enterobacter turicensis should be reclassified as novel species of the genus Cronobacter. In the present work, new genome-scale analyses, including average nucleotide identity, genome-scale phylogeny and k-mer analysis, coupled with previously reported DNA–DNA hybridization values and biochemical characterization strongly indicate that these three species of the genus Enterobacter are not members of the genus Cronobacter, nor do they belong to the re-evaluated genus Enterobacter. Furthermore, data from this polyphasic study indicated that all three species constitute two new genera. We propose reclassifying Enterobacter pulveris and Enterobacter helveticus in the genus Franconibacter gen. nov. as Franconibacter pulveris comb. nov. (type strain 601/05T = LMG 24057T = DSM 19144T) and Franconibacter helveticus comb. nov. (type strain 513/05T = LMG 23732T = DSM 18396T), respectively, and Enterobacter turicensis in the genus Siccibacter gen. nov. as Siccibacter turicensis comb. nov. (type strain 508/05T = LMG 23730T = DSM 18397T). PMID:25028159

  17. Biosorption of multi-heavy metals by coral associated phosphate solubilising bacteria Cronobacter muytjensii KSCAS2.

    PubMed

    Saranya, Kailasam; Sundaramanickam, Arumugam; Shekhar, Sudhanshu; Meena, Moorthy; Sathishkumar, Rengasamy Subramaniyan; Balasubramanian, Thangavel

    2018-06-02

    This paper examines the potential detoxification efficiency of heavy metals by phosphate solubilising bacteria (PSB) that were isolated from coral, sea grass and mangrove environment. Initially, four potential bacterial isolates were selected based on their phosphate solubilisation index from 42 strains and were used for the metal tolerance test. Among the four isolates, KSCAS2 exhibited maximum tolerance to heavy metals and the phenotype indicated the production of extra polymeric substances. In a multi-heavy metal experimental setup at two concentrations (100 and 200 mg L -l ), it has been demonstrated that the bacteria have extracellularly sequestered metal ions in amorphous deposits and this has been confirmed by scanning electron microscopy. In experiments with a 100 mg L -1 initial metal concentration, the percentages of metal removal by bacteria were 55.23% of Cd, 72.45% of Cr, 76.51% of Cu and 61.51% of Zn, respectively. In subsequent experiments, when the metal concentration was increased up to 200 mg L -l , the metal removal capacity decreased as follows: 44.62%, 63.1%, 67% and 52.80% for Cd, Cr, Cu and Zn, respectively. In addition, the biosorption of heavy metals was confirmed by the Fourier transform infrared Spectroscopy (FT-IR) and scanning electron microscopy (SEM) analysis. The heavy metal concentrations in a broth culture were analysed by inductively coupled plasma-optical emission spectroscopy (ICP-OES). The study suggests that PSB Cronobacter muytjensii KSCAS2 can efficiently remove the heavy metals and these bacteria could be used for the metal removal from the agricultural soils. Copyright © 2018. Published by Elsevier Ltd.

  18. Identification of bacterial endophytes associated with traditional medicinal plant Tridax procumbens Linn.

    PubMed

    Preveena, Jagadesan; Bhore, Subhash J

    2013-01-01

    In traditional medicine, Tridax procumbens Linn. is used in the treatment of injuries and wounds. The bacterial endophytes (BEs) of medicinal plants could produce medicinally important metabolites found in their hosts; and hence, the involvement of BEs in conferring wound healing properties to T. Procumbens cannot be ruled out. But, we do not know which types of BEs are associated with T. Procumbens. The objective of this study was to investigate the fast growing and cultivable BEs associated with T. procumbens. Leaves and stems of healthy T. Procumbens plants were collected and cultivable BEs were isolated from surface-sterilized leaf and stem tissue samples using Luria-Bertani (LB) agar (medium) at standard conditions. A polymerase chain reaction was employed to amplify 16S rRNA coding gene fragments from the isolates. Cultivable endophytic bacterial isolates (EBIs) were identified using 16S rRNA gene nucleotide sequence similarity based method of bacterial identification. Altogether, 50 culturable EBIs were isolated. 16S rRNA gene nucleotide sequences analysis using the Basic Local Alignment Search Tool (BLAST) revealed identities of the EBIs. Analysis reveals that cultivable Bacillus spp., Cronobacter sakazakii, Enterobacter spp., Lysinibacillus sphaericus, Pantoea spp., Pseudomonas spp. and Terribacillus saccharophilus are associated with T. Procumbens. Based on the results, we conclude that 24 different types of culturable BEs are associated with traditionally used medicinal plant, T. Procumbens, and require further study.

  19. Evaluation of the microbial safety of child food of animal origin in Greece.

    PubMed

    Liandris, Emmanouil; Gazouli, Maria; Taka, Styliani; Andreadou, Margarita; Vaiopoulou, Anna; Tzimotoudis, Nikolaos; Kasampalidis, Ioannis; Mpaseas, Dionysis; Fyliousis, George; Poltronieri, Palmiro; Poltrionieri, Palmiro; Cook, Nigel; Ikonomopoulos, John

    2014-03-01

    Foodborne illness is a major cause of morbidity and mortality especially for children, even in the developed world. The aim of this study was to assess the microbial safety of food of animal origin intended for consumption by children in Greece. Sampling involved 8 categories of retail products and was completed with a collection of 850 samples. These were tested by PCR and/or culture for Listeria monocytogenes, Campylobacter spp., Escherichia coli O157, Salmonella spp., Cronobacter sakazakii, Brucella spp., and Mycobacterium avium subsp paratuberculosis (MAP). The number of positive results recorded collectively for the pathogens under investigation over the total number of samples tested was 3.52% and 0.12% by PCR and culture, respectively. The most frequently detected pathogen was enterohemorrhagic E. coli (1.29%) followed by Brucella (0.82%) and Listeria (0.82%). DNA belonging to MAP was detected in 0.35% of samples, which was also the percentage of positivity recorded for Campylobacter. The percentage for Salmonella was 0.12%. It can be concluded from the results that there is no indication of noncompliance for the tested food samples. However, detection of DNA belonging to pathogens that are transmissible to humans through food is indicative that constant vigilance regarding food safety is an absolute necessity. © 2014 Institute of Food Technologists®

  20. A β-glucosidase from Oenococcus oeni ATCC BAA-1163 with potential for aroma release in wine: Cloning and expression in E. coli

    PubMed Central

    Michlmayr, Herbert; Schümann, Christina; Wurbs, Phillip; Barreira Braz da Silva, Nuno M.; Rogl, Veronika; Kulbe, Klaus D.; del Hierro, Andrés M.

    2011-01-01

    Lactic acid bacteria (LAB) are responsible for olfactory changes in wine during malolactic fermentation (MLF). A side characteristic of MLF is the release of grape derived aroma compounds from their glycosylated precursors by β-glycosidase activities of these bacteria. Apart from Oenococcus oeni, which is regarded as the most promising species for MLF, glycosidic activities have also been observed in wine related members of the genera Lactobacillus and Pediococcus. Nevertheless, information on the involved enzymes including their potential use in winemaking is limited. In this study we report that β-glucosidases with similar protein sequences can be identified in the genomes of Lactobacillus brevis, O. oeni and Leuconostoc mesenteroides. TTG serves as start codon for the glucosidase gene of O. oeni. The β-glucosidase of O. oeni ATCC BAA-1163 was expressed in E. coli and partially characterized. The enzyme displayed characteristics similar to β-glucosidases isolated from L. brevis and L. mesenteroides. A pH optimum between 5.0 and 5.5, and a Km of 0.17 mmol L−1 pNP-β-D-glucopyranoside were determined. A glycosyltransferase activity was observed in the presence of ethanol. The enzyme from O. oeni was capable to hydrolyze glycosides extracted from Muskat wine. This study also contains a report on glycosidase activities of several LAB species including Oenococcus kitaharae. PMID:21243086

  1. Characterization of C-S lyase from Lactobacillus delbrueckii subsp. bulgaricus ATCC BAA-365 and its potential role in food flavour applications.

    PubMed

    Allegrini, Alessandra; Astegno, Alessandra; La Verde, Valentina; Dominici, Paola

    2017-04-01

    Volatile thiols have substantial impact on the aroma of many beverages and foods. Thus, the control of their formation, which has been linked to C-S lyase enzymatic activities, is of great significance in industrial applications involving food flavours. Herein, we have carried out a spectroscopic and functional characterization of a putative pyridoxal 5'-phosphate (PLP)-dependent C-S lyase from the lactic acid bacterium Lactobacillus delbrueckii subsp. bulgaricus ATCC BAA-365 (LDB C-S lyase). Recombinant LDB C-S lyase exists as a tetramer in solution and shows spectral properties of enzymes containing PLP as cofactor. The enzyme has a broad substrate specificity toward sulphur-containing amino acids with aminoethyl-L-cysteine and L-cystine being the most effective substrates over L-cysteine and L-cystathionine. Notably, the protein also reveals cysteine-S-conjugate β-lyase activity in vitro, and is able to cleave a cysteinylated substrate precursor into the corresponding flavour-contributing thiol, with a catalytic efficiency higher than L-cystathionine. Contrary to similar enzymes of other lactic acid bacteria however, LDB C-S lyase is not capable of α,γ-elimination activity towards L-methionine to produce methanethiol, which is a significant compound in flavour development. Based on our results, future developments can be expected regarding the flavour-forming potential of Lactobacillus C-S lyase and its use in enhancing food flavours. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  2. Identification of bacterial endophytes associated with traditional medicinal plant Tridax procumbens Linn.

    PubMed Central

    Preveena, Jagadesan; Bhore, Subhash J.

    2013-01-01

    Background: In traditional medicine, Tridax procumbens Linn. is used in the treatment of injuries and wounds. The bacterial endophytes (BEs) of medicinal plants could produce medicinally important metabolites found in their hosts; and hence, the involvement of BEs in conferring wound healing properties to T. Procumbens cannot be ruled out. But, we do not know which types of BEs are associated with T. Procumbens. Objective: The objective of this study was to investigate the fast growing and cultivable BEs associated with T. procumbens. Materials and Methods: Leaves and stems of healthy T. Procumbens plants were collected and cultivable BEs were isolated from surface-sterilized leaf and stem tissue samples using Luria-Bertani (LB) agar (medium) at standard conditions. A polymerase chain reaction was employed to amplify 16S rRNA coding gene fragments from the isolates. Cultivable endophytic bacterial isolates (EBIs) were identified using 16S rRNA gene nucleotide sequence similarity based method of bacterial identification. Results: Altogether, 50 culturable EBIs were isolated. 16S rRNA gene nucleotide sequences analysis using the Basic Local Alignment Search Tool (BLAST) revealed identities of the EBIs. Analysis reveals that cultivable Bacillus spp., Cronobacter sakazakii, Enterobacter spp., Lysinibacillus sphaericus, Pantoea spp., Pseudomonas spp. and Terribacillus saccharophilus are associated with T. Procumbens. Conclusion: Based on the results, we conclude that 24 different types of culturable BEs are associated with traditionally used medicinal plant, T. Procumbens, and require further study. PMID:24501447

  3. Cultivable endophytic bacteria from leaf bases of Agave tequilana and their role as plant growth promoters

    PubMed Central

    Martínez-Rodríguez, Julia del C.; la Mora-Amutio, Marcela De; Plascencia-Correa, Luis A.; Audelo-Regalado, Esmeralda; Guardado, Francisco R.; Hernández-Sánchez, Elías; Peña-Ramírez, Yuri J.; Escalante, Adelfo; Beltrán-García, Miguel J.; Ogura, Tetsuya

    2014-01-01

    Agave tequilana Weber var. ‘Azul’ is grown for the production of tequila, inulin and syrup. Diverse bacteria inhabit plant tissues and play a crucial role for plant health and growth. In this study culturable endophytic bacteria were extracted from leaf bases of 100 healthy Agave tequilana plants. In plant tissue bacteria occurred at mean population densities of 3 million CFU/g of fresh plant tissue. Three hundred endophytic strains were isolated and 16s rDNA sequences grouped the bacteria into eight different taxa that shared high homology with other known sequences. Bacterial endophytes were identified as Acinectobacter sp., A. baumanii, A. bereziniae, Cronobacter sakazakii, Enterobacter hormaechei, Bacillus sp. Klebsiella oxytoca, Pseudomonas sp., Enterococcus casseliflavus, Leuconostoc mesenteroides subsp. mesenteroides and Gluconobacter oxydans. Isolates were confirmed to be plant growth promoting bacteria (PGPB) by their capacities for nitrogen fixation, auxin production, phosphate solubilization, or antagonism against Fusarium oxysporum AC132. E. casseliflavus JM47 and K. oxytoca JM26 secreted the highest concentrations of IAA. The endophyte Acinectobacter sp. JM58 exhibited the maximum values for nitrogen fixation and phosphate solubilization index (PSI). Inhibition of fungi was found in Pseudomonas sp. JM9p and K. oxytoca JM26. Bacterial endophytes show promise for use as bio-inoculants for agave cultivation. Use of endophytes to enhance cultivation of agave may be particularly important for plants produced by micropropagation techniques, where native endophytes may have been lost. PMID:25763038

  4. Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae Isolated from Vegetables Imported from the Dominican Republic, India, Thailand, and Vietnam

    PubMed Central

    Zurfluh, Katrin; Nüesch-Inderbinen, Magdalena; Morach, Marina; Zihler Berner, Annina; Hächler, Herbert

    2015-01-01

    To examine to what extent fresh vegetables imported into Switzerland represent carriers of extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae, 169 samples of different types of fresh vegetables imported into Switzerland from the Dominican Republic, India, Thailand, and Vietnam were analyzed. Overall, 25.4% of the vegetable samples yielded one or more ESBL-producing Enterobacteriaceae, 78.3% of which were multidrug resistant. Sixty isolates were obtained: Escherichia coli, 26; Klebsiella pneumoniae, 26; Enterobacter cloacae, 6; Enterobacter aerogenes, 1; and Cronobacter sakazakii, 1. We found 29 isolates producing CTX-M-15, 8 producing CTX-M-14, 7 producing CTX-M-55, 3 producing CTX-M-65, 1 each producing CTX-M-1, CTX-M-3, CTX-M-27, and CTX-M-63, 5 producing SHV-2, 3 producing SHV-12, and 1 producing SHV-2a. Four of the E. coli isolates belonged to epidemiologically important clones: CTX-M-15-producing B2:ST131 (1 isolate), D:ST405 (1 isolate), and D:ST38 (2 isolates). One of the D:ST38 isolates belonged to the extraintestinal enteroaggregative E. coli (EAEC) D:ST38 lineage. Two of the K. pneumoniae isolates belonged to the epidemic clones sequence type 15 (ST15) and ST147. The occurrence of antibiotic-resistant pathogenic and commensal Enterobacteriaceae in imported agricultural foodstuffs constitutes a source of ESBL genes and a concern for food safety. PMID:25724954

  5. Label-Free 3D Ag Nanoflower-Based Electrochemical Immunosensor for the Detection of Escherichia coli O157:H7 Pathogens

    NASA Astrophysics Data System (ADS)

    Huang, He; Liu, Minghuan; Wang, Xiangsheng; Zhang, Wenjie; Yang, Da-Peng; Cui, Lianhua; Wang, Xiansong

    2016-11-01

    It is highly desirable to develop a rapid and simple method to detect pathogens. Combining nanomaterials with electrochemical techniques is an efficient way for pathogen detection. Herein, a novel 3D Ag nanoflower was prepared via a biomineralization method by using bovine serum albumin (BSA) as a template. It was adopted as a sensing interface to construct an electrochemical bacteria immunosensor for the rapid detection of foodborne pathogens Escherichia coli ( E. coli) O157:H7. Bacterial antibody was immobilized onto the surface of Ag nanoflowers through covalent conjugation. Electrochemical impedance spectroscopy (EIS) was used to detect and validate the resistance changes, where [Fe(CN)6]3-/4- acted as the redox probe. A linear relation between R et and E. coli concentration was obtained in the E. coli concentration range of 3.0 × 102-3.0 × 108 cfu mL-1. The as-prepared biosensor gave rise to an obvious response to E. coli but had no distinct response to Cronobacter sakazakii, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus albus, Lactobacillus easei, and Shigella flexneri, revealing a high selectivity for the detection of the pathogens down to 100 cfu mL-1 in a short time. We believe that this BSA-conjugated 3D Ag nanoflowers could be used as a powerful interface material with good conductivity and biocompatibility for improving pathogen detection and treatment in the field of medicine, environment, and food safety.

  6. Cultivable endophytic bacteria from leaf bases of Agave tequilana and their role as plant growth promoters.

    PubMed

    Martínez-Rodríguez, Julia del C; De la Mora-Amutio, Marcela; Plascencia-Correa, Luis A; Audelo-Regalado, Esmeralda; Guardado, Francisco R; Hernández-Sánchez, Elías; Peña-Ramírez, Yuri J; Escalante, Adelfo; Beltrán-García, Miguel J; Ogura, Tetsuya

    2014-01-01

    Agave tequilana Weber var. 'Azul' is grown for the production of tequila, inulin and syrup. Diverse bacteria inhabit plant tissues and play a crucial role for plant health and growth. In this study culturable endophytic bacteria were extracted from leaf bases of 100 healthy Agave tequilana plants. In plant tissue bacteria occurred at mean population densities of 3 million CFU/g of fresh plant tissue. Three hundred endophytic strains were isolated and 16s rDNA sequences grouped the bacteria into eight different taxa that shared high homology with other known sequences. Bacterial endophytes were identified as Acinectobacter sp., A. baumanii, A. bereziniae, Cronobacter sakazakii, Enterobacter hormaechei, Bacillus sp. Klebsiella oxytoca, Pseudomonas sp., Enterococcus casseliflavus, Leuconostoc mesenteroides subsp. mesenteroides and Gluconobacter oxydans. Isolates were confirmed to be plant growth promoting bacteria (PGPB) by their capacities for nitrogen fixation, auxin production, phosphate solubilization, or antagonism against Fusarium oxysporum AC132. E. casseliflavus JM47 and K. oxytoca JM26 secreted the highest concentrations of IAA. The endophyte Acinectobacter sp. JM58 exhibited the maximum values for nitrogen fixation and phosphate solubilization index (PSI). Inhibition of fungi was found in Pseudomonas sp. JM9p and K. oxytoca JM26. Bacterial endophytes show promise for use as bio-inoculants for agave cultivation. Use of endophytes to enhance cultivation of agave may be particularly important for plants produced by micropropagation techniques, where native endophytes may have been lost.

  7. Endovascular treatment of ectopic bronchial artery aneurysm with brachiocephalic artery stent placement and coil embolization

    PubMed Central

    Di, Xiao; Ji, Dong-Hua; Chen, Yu; Liu, Chang-Wei; Liu, Bao; Yang, Juan

    2016-01-01

    Abstract Background: Bronchial artery aneurysm (BAA) is an uncommon but potentially life-threatening disease, and multiple BAAs are even rarer. Clinically, the tortuous and short neck of a BAA may present significant challenges for invasive intervention. Methods: This report describes the detailed process of diagnosis and treatment and includes a literature review of the etiology, clinical presentation, and therapeutic management of BAA. Results: A rare case of multiple BAAs, with one having an inflow artery arising from the brachiocephalic trunk, was referred to our hospital. The patient was successfully treated with coil embolization and brachiocephalic artery stent placement. In addition, we conducted a literature review involving 63 cases of BAA. BAA was most commonly associated with bronchiectasis and was located predominantly in the mediastinum. There was no significant difference between the diameters of the ruptured aneurysms and those of the nonruptured aneurysms (P = 0.115). Transcatheter arterial embolization was the most commonly adopted technique to treat BAA, while thoracic aortic endovascular repair was selected if the neck between the aneurysm and the aorta was short. Subgroup analysis suggested that patients with > 1 BAA were significantly more likely to be female than male (χ2 test, P = 0.034). Conclusion: Transcatheter coil embolization combined with stent placement could be a reasonable treatment option for BAAs with a tortuous and short neck. According to our literature review, patients with multiple BAAs display distinctive clinical characteristics compared with patients with a single BAA. PMID:27583854

  8. Identification and characterization of a novel β-galactosidase from Victivallis vadensis ATCC BAA-548, an anaerobic fecal bacterium.

    PubMed

    Temuujin, Uyangaa; Chi, Won-Jae; Park, Jae-Sun; Chang, Yong-Keun; Song, Jae Yang; Hong, Soon-Kwang

    2012-12-01

    Victivallis vadensis ATCC BAA-548 is a Gram-negative, anaerobic bacterium that was isolated from a human fecal sample. From the genomic sequence of V. vadensis, one gene was found to encode agarase; however, its enzymatic properties have never been characterized. The gene encoding the putative agarase (NCBI reference number ZP_01923925) was cloned by PCR and expressed in E. coli Rosetta-gami by using the inducible T(7) promoter of pET28a(+). The expressed protein with a 6×His tag at the N-terminus was named His6-VadG925 and purified as a soluble protein by Ni(2+)-NTA agarose affinity column chromatography. The purification of the enzyme was 26.8-fold, with a yield of 73.2% and a specific activity of 1.02 U/mg of protein. The purified His6-VadG925 produced a single band with an approximate MW of 155 kDa, which is consistent with the calculated value (154,660 Da) including the 6×His tag. Although VadG925 and many of its homologs were annotated as agarases, it did not hydrolyze agarose. Instead, purified His(6)-VadG925 hydrolyzed an artificial chromogenic substrate, p-nitrophenyl-β-D-galactopyranoside, but not p-nitrophenyl-α-D-galactopyranoside. The optimum pH and temperature for this β-galactosidase activity were pH 7.0 and 40°C, respectively. The K(m) and V(max) of His6-VadG925 towards p-nitrophenyl-β-D-galactopyranoside were 1.69 mg/ml (0.0056 M) and 30.3 U/mg, respectively. His6-VadG925 efficiently hydrolyzed lactose into glucose and galactose, which was demonstrated by TLC and mass spectroscopy. These results clearly demonstrated that VadG925 is a novel β-galactosidase that can hydrolyze lactose, which is unusual because of its low homology to validated β-galactosidases.

  9. Selected pathogens of concern to industrial food processors: infectious, toxigenic, toxico-infectious, selected emerging pathogenic bacteria

    USDA-ARS?s Scientific Manuscript database

    Enterobacter sakazakii is a rod-shaped bacterium that has been implicated in rare cases of neonatal sepsis, meningitis and is associated with necrotizing enterocolitis in infants. Over 80 cases of E. sakazakii-related illness have been reported, although few of these have occurred in adults. There...

  10. Branchial arch anomalies: Recurrence, malignant degeneration and operative complications.

    PubMed

    Al-Mufarrej, Faisal; Stoddard, David; Bite, Uldis

    2017-06-01

    Branchial arch anomalies (BAA) represent one of the commonest pediatric neck masses, but large case series are lacking with none specifically examining risk of recurrence, surgical complications, and malignancy. Retrospective study of patients with BAA at Mayo Clinic from 1/1/1976-7/29/2011. Features studied include age, gender, location, BAA type, symptoms, recurrence, preoperative management, extent of surgery, pathology as well as presence of tracts. Associations with tracts, operative complications, and recurrence were evaluated. 421 subjects underwent BAA excision during the study period at our institution. Subjects with tracts were symptomatic earlier. Four cases (mean age 60.3 years) of malignancy were identified. Among the 358 (non-remenant) BAA patients with no previous excision, 3.6% recurred at a mean of 47.1 months following surgery. Patients who underwent incision and drainage prior to BAA excision were 3.4 times more likely to recur. 2% experienced complications. Age, BAA type, preoperative imaging and extent of surgery did not affect recurrence or complication rates. Patients with history of preoperative incision and drainage should be followed closely for recurrence the first four years. Early BAA excision is not associated with higher complication rate. Extent of resection should be determined by gross margins of BAA. Malignant degeneration was not seen in children. Malignancies have been seen in older patients (over 45 years) diagnosed with BAA, and a thorough work-up is important for correct diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. [Coil Embolization of Bronchial Artery Aneurysm;Report of a Case].

    PubMed

    Hagiwara, Kenichi; Moriya, Hiroshi; Sato, Yoshiyuki

    2018-05-01

    An 82-year-old male was admitted due to mild chest discomfort. Enhanced computed tomography showed a large bronchial artery aneurysm(BAA) of 26×27 mm at the left hilus. To avoid the rupture of BAA, coil embolization alone was performed. There has been no enlargement of BAA for these 4 years. In general, coil embolization only should be indicated in a patient with BAA with a stalk because of thoracic endovascular aortic repair (TEVAR) being off-label and low cost performance. TEVAR would be considered as a last resort only in case of enlarging BAA even after coil embolization.

  12. Bovine aortic arch with supravalvular aortic stenosis.

    PubMed

    Idhrees, Mohammed; Cherian, Vijay Thomas; Menon, Sabarinath; Mathew, Thomas; Dharan, Baiju S; Jayakumar, K

    2016-09-01

    A 5-year-old boy was diagnosed to have supravalvular aortic stenosis (SVAS). On evaluation of CT angiogram, there was associated bovine aortic arch (BAA). Association of BAA with SVAS has not been previously reported in literature, and to best of our knowledge, this is the first case report of SVAS with BAA. Recent studies show BAA as a marker for aortopathy. SVAS is also an arteriopathy. In light of this, SVAS can also possibly be a manifestation of aortopathy associated with BAA. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  13. Biocontrol and Rapid Detection of Food-Borne Pathogens Using Bacteriophages and Endolysins

    PubMed Central

    Bai, Jaewoo; Kim, You-Tae; Ryu, Sangryeol; Lee, Ju-Hoon

    2016-01-01

    Bacteriophages have been suggested as natural food preservatives as well as rapid detection materials for food-borne pathogens in various foods. Since Listeria monocytogenes-targeting phage cocktail (ListShield) was approved for applications in foods, numerous phages have been screened and experimentally characterized for phage applications in foods. A single phage and phage cocktail treatments to various foods contaminated with food-borne pathogens including E. coli O157:H7, Salmonella enterica, Campylobacter jejuni, Listeria monocytogenes, Staphylococcus aureus, Cronobacter sakazakii, and Vibrio spp. revealed that they have great potential to control various food-borne pathogens and may be alternative for conventional food preservatives. In addition, phage-derived endolysins with high host specificity and host lysis activities may be preferred to food applications rather than phages. For rapid detection of food-borne pathogens, cell-wall binding domains (CBDs) from endolysins have been suggested due to their high host-specific binding. Fluorescence-tagged CBDs have been successfully evaluated and suggested to be alternative materials of expensive antibodies for various detection applications. Most recently, reporter phage systems have been developed and tested to confirm their usability and accuracy for specific detection. These systems revealed some advantages like rapid detection of only viable pathogenic cells without interference by food components in a very short reaction time, suggesting that these systems may be suitable for monitoring of pathogens in foods. Consequently, phage is the next-generation biocontrol agent as well as rapid detection tool to confirm and even identify the food-borne pathogens present in various foods. PMID:27092128

  14. The Epidemiology, Management, and Outcomes of Bacterial Meningitis in Infants.

    PubMed

    Ouchenir, Lynda; Renaud, Christian; Khan, Sarah; Bitnun, Ari; Boisvert, Andree-Anne; McDonald, Jane; Bowes, Jennifer; Brophy, Jason; Barton, Michelle; Ting, Joseph; Roberts, Ashley; Hawkes, Michael; Robinson, Joan L

    2017-07-01

    The pathogens that cause bacterial meningitis in infants and their antimicrobial susceptibilities may have changed in this era of increasing antimicrobial resistance, use of conjugated vaccines, and maternal antibiotic prophylaxis for group B Streptococcus (GBS). The objective was to determine the optimal empirical antibiotics for bacterial meningitis in early infancy. This was a cohort study of infants <90 days of age with bacterial meningitis at 7 pediatric tertiary care hospitals across Canada in 2013 and 2014. There were 113 patients diagnosed with proven meningitis ( n = 63) or suspected meningitis ( n = 50) presented at median 19 days of age, with 63 patients (56%) presenting a diagnosis from home. Predominant pathogens were Escherichia coli ( n = 37; 33%) and GBS ( n = 35; 31%). Two of 15 patients presenting meningitis on day 0 to 6 had isolates resistant to both ampicillin and gentamicin ( E coli and Haemophilus influenzae type B). Six of 60 infants presenting a diagnosis of meningitis from home from day 7 to 90 had isolates, for which cefotaxime would be a poor choice ( Listeria monocytogenes [ n = 3], Enterobacter cloacae , Cronobacter sakazakii , and Pseudomonas stutzeri ). Sequelae were documented in 84 infants (74%), including 8 deaths (7%). E coli and GBS remain the most common causes of bacterial meningitis in the first 90 days of life. For empirical therapy of suspected bacterial meningitis, one should consider a third-generation cephalosporin (plus ampicillin for at least the first month), potentially substituting a carbapenem for the cephalosporin if there is evidence for Gram-negative meningitis. Copyright © 2017 by the American Academy of Pediatrics.

  15. Zinc transporter-8 autoantibodies improve prediction of type 1 diabetes in relatives positive for the standard biochemical autoantibodies.

    PubMed

    Yu, Liping; Boulware, David C; Beam, Craig A; Hutton, John C; Wenzlau, Janet M; Greenbaum, Carla J; Bingley, Polly J; Krischer, Jeffrey P; Sosenko, Jay M; Skyler, Jay S; Eisenbarth, George S; Mahon, Jeffrey L

    2012-06-01

    We assessed diabetes risk associated with zinc transporter-8 antibodies (ZnT8A), islet cell antibodies (ICA), and HLA type and age in relatives of people with type 1 diabetes with the standard biochemical autoantibodies (BAA) to insulin (IAA), GAD65 (GAD65A), and/or insulinoma-associated protein 2 antigen (IA-2A). For this analysis, 2,256 relatives positive for at least one BAA, of whom 142 developed diabetes, were tested for ZnT8A, ICA, and HLA genotype followed by biannual oral glucose tolerance tests. ZnT8A were also tested in 911 randomly chosen antibody-negative relatives. ZnT8A were associated with the other BAA (548 of 2,256 [24.3%] BAA(+) vs. 8 of 911 [0.8%] BAA(-), P < 0.001) and BAA number (177 of 1,683 [10.5%] single-, 221 of 384 [57.6%] double-, and 150 of 189 [79.4%] triple-BAA positivity, P < 0.001). The 4-year diabetes risk was higher in single BAA(+) relatives with ZnT8A than ZnT8A(-) relatives (31 vs. 7%, P < 0.001). In multivariable analysis, age ≤ 20 years (hazard ratio 2.13, P = 0.03), IA-2A (2.15, P = 0.005), IAA (1.73, P = 0.01), ICA (2.37, P = 0.002), and ZnT8A (1.87, P = 0.03) independently predicted diabetes, whereas HLA type (high and moderate vs. low risk) and GAD65A did not (P = 0.81 and 0.86, respectively). In relatives with one standard BAA, ZnT8A identified a subset at higher diabetes risk. ZnT8A predicted diabetes independently of ICA, the standard BAA, age, and HLA type. ZnT8A should be included in type 1 diabetes prediction and prevention studies.

  16. Endovascular Therapy of Bronchial Artery Aneurysm: Five Cases With Six Aneurysms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lue, Peng-Hua, E-mail: whycn77@sina.com; Wang Lifu; Su Yusheng

    2011-06-15

    The objective of this study was to investigate the effect of transcatheter arterial embolization (TAE) with N-butyl-2-cyanoacrylate (NBCA)-Lipiodol mixture in patients with bronchial artery aneurysm (BAA). From January 2005 to January 2010, five patients presenting hemoptysis with six BAAs were treated with NBCA-Lipiodol mixture, including intra-aneurysm embolization (IAE) in one patient. Adjuvant embolization with spherical polyvinyl alcohol (PVA) embolic microparticles or NBCA was first performed to embolize the distal engorged bronchiectatic arteries. Bronchial arterial angiography showed six BAAs (four in the right lobe and two in the left lobe) and some engorged, tortuous bronchial arteries. TAE through microcatheter was successfulmore » in all cases. Postembolization angiogram demonstrated the NBCA cast and total occlusion of BAAs and bronchiectatic engorged vessels. After these procedures, hemoptysis completely disappeared in all patients. Follow-up computed tomography (CT) scan was performed at an average of 3 months (range 2 to 6), which showed no enhancement of BAAs and accumulation of NBCA. TAE is a minimally invasive, effective, and reliable approach for treatment for patients with BAA. NBCA-Lipiodol mixture provides a good choice for treatment of BAA, especially when catheterization of the efferent branches is impossible.« less

  17. Prevalence of foodborne pathogens in retailed foods in Thailand.

    PubMed

    Ananchaipattana, Chiraporn; Hosotani, Yukie; Kawasaki, Susumu; Pongsawat, Sirikae; Latiful, Bari Md; Isobe, Seiichiro; Inatsu, Yasuhiro

    2012-09-01

    The consumption of foodborne pathogens contaminated in food is one of the major causes of diarrheal diseases in Thailand. The objective of this study was to evaluate the prevalence and types of contaminating bacteria in retailed foodstuffs in Thailand. Food from four categories (137 samples total), including meat (51 samples), vegetables (38 samples), fish or seafood (37 samples), and fermented food (11 samples), was purchased randomly from seven different open-markets and seven supermarkets in Thailand from August 2010 to March 2011. Seven types of major foodborne pathogens were identified using conventional culture methods. Approximately 80% of meat samples tested was contaminated with Salmonella spp. In contrast, the Salmonella spp. contamination rate of vegetable (5%) or fermented food (9%) samples was comparatively low. Six strains of Cronobacter sakazakii and two strains of Yersinia enterocolitica were also isolated. A substantially higher rate of contamination by Bacillus cereus was observed in fermented food (82%) than in samples of meat (2%) and fish or seafood (5%). Seven Listeria spp. isolates were obtained from meat and fish or seafood samples. Approximately 39% of samples tested were found to be contaminated with Staphylococcus spp. (54 isolates). The rate of bacterial contamination of meat did not depend on the type of market. However, the contamination rate of Staphylococcus spp. in vegetables was higher in open markets than in supermarkets, and the contamination rate of Salmonella spp. and Staphylococcus spp. in fish or seafood samples purchased in open markets was likewise higher than in those purchased in supermarkets. Therefore, improvement of hygienic practices throughout the food chain may be required to reduce the risk of food poisoning.

  18. Advantages and challenges of increased antimicrobial copper use and copper mining.

    PubMed

    Elguindi, Jutta; Hao, Xiuli; Lin, Yanbing; Alwathnani, Hend A; Wei, Gehong; Rensing, Christopher

    2011-07-01

    Copper is a highly utilized metal for electrical, automotive, household objects, and more recently as an effective antimicrobial surface. Copper-containing solutions applied to fruits and vegetables can prevent bacterial and fungal infections. Bacteria, such as Salmonellae and Cronobacter sakazakii, often found in food contamination, are rapidly killed on contact with copper alloys. The antimicrobial effectiveness of copper alloys in the healthcare environment against bacteria causing hospital-acquired infections such as methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli O157:H7, and Clostridium difficile has been described recently. The use of copper and copper-containing materials will continue to expand and may lead to an increase in copper mining and production. However, the copper mining and manufacturing industry and the consumer do not necessarily enjoy a favorable relationship. Open pit mining, copper mine tailings, leaching products, and deposits of toxic metals in the environment often raises concerns and sometimes public outrage. In addition, consumers may fear that copper alloys utilized as antimicrobial surfaces in food production will lead to copper toxicity in humans. Therefore, there is a need to mitigate some of the negative effects of increased copper use and copper mining. More thermo-tolerant, copper ion-resistant microorganisms could improve copper leaching and lessen copper groundwater contamination. Copper ion-resistant bacteria associated with plants might be useful in biostabilization and phytoremediation of copper-contaminated environments. In this review, recent progress in microbiological and biotechnological aspects of microorganisms in contact with copper will be presented and discussed, exploring their role in the improvement for the industries involved as well as providing better environmental outcomes.

  19. Fully Automated Deep Learning System for Bone Age Assessment.

    PubMed

    Lee, Hyunkwang; Tajmir, Shahein; Lee, Jenny; Zissen, Maurice; Yeshiwas, Bethel Ayele; Alkasab, Tarik K; Choy, Garry; Do, Synho

    2017-08-01

    Skeletal maturity progresses through discrete phases, a fact that is used routinely in pediatrics where bone age assessments (BAAs) are compared to chronological age in the evaluation of endocrine and metabolic disorders. While central to many disease evaluations, little has changed to improve the tedious process since its introduction in 1950. In this study, we propose a fully automated deep learning pipeline to segment a region of interest, standardize and preprocess input radiographs, and perform BAA. Our models use an ImageNet pretrained, fine-tuned convolutional neural network (CNN) to achieve 57.32 and 61.40% accuracies for the female and male cohorts on our held-out test images. Female test radiographs were assigned a BAA within 1 year 90.39% and within 2 years 98.11% of the time. Male test radiographs were assigned 94.18% within 1 year and 99.00% within 2 years. Using the input occlusion method, attention maps were created which reveal what features the trained model uses to perform BAA. These correspond to what human experts look at when manually performing BAA. Finally, the fully automated BAA system was deployed in the clinical environment as a decision supporting system for more accurate and efficient BAAs at much faster interpretation time (<2 s) than the conventional method.

  20. Resistance of pathogenic bacteria on the surface of stainless steel depending on attachment form and efficacy of chemical sanitizers.

    PubMed

    Bae, Young-Min; Baek, Seung-Youb; Lee, Sun-Young

    2012-02-15

    Various bacteria including food spoilage bacteria and pathogens can form biofilms on different food processing surfaces, leading to potential food contamination or spoilage. Therefore, the survival of foodborne pathogens (Escherichia coli O157:H7, Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, Cronobacter sakazakii) in different forms (adhered cells, biofilm producing in TSB, biofilm producing at RH 100%) on the surface of stainless steel and stored at various relative humidities (RH 23%, 43%, 68%, 85%, and 100%) at room temperature for 5 days was investigated in this study. Additionally, the efficacy of chemical sanitizers (chlorine-based and alcohol-based commercial sanitizers) on inhibiting various types of biofilms of E. coli O157:H7 and S. aureus on the surface of stainless steel was investigated. The number of pathogens on the surface of stainless steel in TSB stored at 25°C for 7 days or RH 100% at 25°C for 7 days was significantly increased and resulted in the increase of 3 log(10) CFU/coupon after 1 day, and these levels were maintained for 7 days. When stainless steel coupons were stored at 25°C for 5 days, the number of pathogens on the surface of stainless steel was significantly reduced after storage at RH 23%, 43%, 68%, and 85%, but not at 100%. When the bacteria formed biofilms on the surface of stainless steel in TSB after 6 days, the results were similar to those of the attached form. However, levels of S. aureus and C. sakazakii biofilms were more slowly reduced after storage at RH 23%, 43%, 68%, and 85% for 5 days than were those of the other pathogens. Formation of biofilms stored at RH 100% for 5 days displayed the highest levels of resistance to inactivation. Treatment with the alcohol sanitizer was very effective at inactivating attached pathogens or biofilms on the surface of stainless steel. Reduction levels of alcohol sanitizer treatment ranged from 1.91 to 4.77 log and from 4.35 to 5.35 log CFU/coupon in E. coli

  1. Crystal induced phosphorescence from Benz(a)anthracene microcrystals at room temperature

    NASA Astrophysics Data System (ADS)

    Maity, Samir; Mazumdar, Prativa; Shyamal, Milan; Sahoo, Gobinda Prasad; Misra, Ajay

    2016-03-01

    Pure organic compounds that are also phosphorescent at room temperature are very rare in literature. Here, we report efficient phosphorescence emission from aggregated hydrosol of Benz(a)anthracene (BaA) at room temperature. Aggregated hydrosol of BaA has been synthesized by re-precipitation method and SDS is used as morphology directing agent. Morphology of the particles is characterized using optical and scanning electronic microcopy (SEM). Photophysical properties of the aggregated hydrosol are carried out using UV-vis, steady state and time resolved fluorescence study. The large stoke shifted structured emission from aggregated hydrosol of BaA has been explained due to phosphorescence emission of BaA at room temperature. In the crystalline state, the restricted intermolecular motions (RIM) such as rotations and vibrations are activated by crystal lattice. This rigidification effect makes the chromophore phosphorescent at room temperature. The possible stacking arrangement of the neighboring BaA within the aggregates has been substantiated by computing second order Fukui parameter as local reactivity descriptors. Computational study also reveals that the neighboring BaA molecules are present in parallel slipped conformation in its aggregated crystalline form.

  2. Assure Access to the Maritime Battlespace

    DTIC Science & Technology

    2012-10-22

    Energy Section ( PEM Fuel Cells & Stirling Engines) Smart Battery High Pressure Gas Smart Li-Ion Battery BAA Technologies Energy Section... Fuel Cells and Advanced Reactant Storage 30 Days Endurance Ref Mission LDUUV INP Energy Plan 14 At Sea Test and Analysis At Sea Test and...undersea vehicles capable of operating near shore BAA Contracts awarded BAA Open for Competition Stirling Engine Demo UUV Fuel Cell 500hr

  3. Novel Method for Reliable Identification of Siccibacter and Franconibacter Strains: from “Pseudo-Cronobacter” to New Enterobacteriaceae Genera

    PubMed Central

    Vlach, Jiří; Junková, Petra; Karamonová, Ludmila; Blažková, Martina; Fukal, Ladislav

    2017-01-01

    ABSTRACT In the last decade, strains of the genera Franconibacter and Siccibacter have been misclassified as first Enterobacter and later Cronobacter. Because Cronobacter is a serious foodborne pathogen that affects premature neonates and elderly individuals, such misidentification may not only falsify epidemiological statistics but also lead to tests of powdered infant formula or other foods giving false results. Currently, the main ways of identifying Franconibacter and Siccibacter strains are by biochemical testing or by sequencing of the fusA gene as part of Cronobacter multilocus sequence typing (MLST), but in relation to these strains the former is generally highly difficult and unreliable while the latter remains expensive. To address this, we developed a fast, simple, and most importantly, reliable method for Franconibacter and Siccibacter identification based on intact-cell matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Our method integrates the following steps: data preprocessing using mMass software; principal-component analysis (PCA) for the selection of mass spectrum fingerprints of Franconibacter and Siccibacter strains; optimization of the Biotyper database settings for the creation of main spectrum projections (MSPs). This methodology enabled us to create an in-house MALDI MS database that extends the current MALDI Biotyper database by including Franconibacter and Siccibacter strains. Finally, we verified our approach using seven previously unclassified strains, all of which were correctly identified, thereby validating our method. IMPORTANCE We show that the majority of methods currently used for the identification of Franconibacter and Siccibacter bacteria are not able to properly distinguish these strains from those of Cronobacter. While sequencing of the fusA gene as part of Cronobacter MLST remains the most reliable such method, it is highly expensive and time-consuming. Here, we demonstrate a

  4. Fe-based bulk amorphous alloys with iron contents as high as 82 at%

    NASA Astrophysics Data System (ADS)

    Li, Jin-Feng; Liu, Xue; Zhao, Shao-Fan; Ding, Hong-Yu; Yao, Ke-Fu

    2015-07-01

    Fe-based bulk amorphous alloys (BAAs) with high Fe contents are advantageous due to their high saturation magnetization and low cost. However, preparing Fe-based BAAs with Fe contents higher than 80 at% is difficult due to their poor glass forming abilities (GFA). In this study, an Fe81P8.5C5.5B2Si3 BAA with a diameter of 1 mm and a saturation magnetization of 1.56 T was successfully prepared using the fluxing and copper mold casting methods. In addition, by introducing a small amount of elemental Mo to the alloy, an Fe82Mo1P6.5C5.5B2Si3 BAA rod with a diameter of 1 mm, a high saturation magnetization of 1.59 T, a high yield stress of 3265 MPa, and a clear plasticity of 1.3% was prepared in the same way. The cost effectiveness and good magnetic properties of these newly-developed Fe-based BAAs with Fe contents as high as 82 at% would be advantageous and promising for industrial applications.

  5. Outbreak of a novel Enterobacter sp. carrying blaCTX-M-15 in a neonatal unit of a tertiary care hospital in Tanzania.

    PubMed

    Mshana, Stephen E; Gerwing, Lisa; Minde, Mercy; Hain, Torsten; Domann, Eugen; Lyamuya, Eligius; Chakraborty, Trinad; Imirzalioglu, Can

    2011-09-01

    Enterobacter hormaechei and Cronobacter sakazakii are amongst the most important causes of outbreaks of neonatal sepsis associated with powdered milk. In this study, we report for the first time an outbreak of a novel Enterobacter sp. harbouring bla(CTX-M-15) in a neonatal unit in Tanzania. Seventeen Gram-negative enteric isolates from neonatal blood cultures were studied. Antibiotic susceptibility was assessed by disc diffusion testing, and the presence of the bla(CTX-M-15) gene was established by polymerase chain reaction (PCR) and sequencing. Isolates were typed by pulsed-field gel electrophoresis (PFGE). Identification by biochemical profiling was followed by nucleotide sequencing of 16S ribosomal DNA (rDNA), rpoB and hsp60 alleles. Environmental sampling was done and control measures were established. Isolates were initially misidentified based on their fermentation characteristics and agglutination as Salmonella enterica serotype Paratyphi. All isolates were resistant to multiple antibiotics, except for ciprofloxacin and carbapenems, and were found to harbour bla(CTX-M-15) on a 291-kb narrow-range plasmid. PFGE analysis indicated the clonal outbreak of a single strain, infecting 17 neonates with a case fatality rate of 35%. The same strain was isolated from a milk bucket. Phylogenetic analysis using 16S rDNA, rpoB and hsp60 sequences permitted no definitive identification, clustering the strains in the Enterobacter cloacae complex with similarities of 92-98.8%. The data describe an outbreak of a novel bla(CTX-M-15)-positive, multiresistant Enterobacter strain in an African neonatal unit that can easily be misidentified taxonomically. These data highlight the need for constant surveillance of bacteria harbouring extended-spectrum β-lactamases as well as improvements in hygiene measures in developing countries. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  6. Enterobacter and Klebsiella species isolated from fresh vegetables marketed in Valencia (Spain) and their clinically relevant resistances to chemotherapeutic agents.

    PubMed

    Falomir, María Pilar; Rico, Hortensia; Gozalbo, Daniel

    2013-12-01

    Occurrence of antibiotic-resistant pathogenic or commensal enterobacteria in marketed agricultural foodstuffs may contribute to their incorporation into the food chain and constitutes an additional food safety concern. In this work, we have determined the clinically relevant resistances to 11 common chemotherapeutic agents in Enterobacter and Klebsiella isolates from fresh vegetables from various sources (supermarkets and greengrocers' shops in Valencia, Spain). A total of 96 isolates were obtained from 160 vegetables analyzed (50% positive samples): 68 Enterobacter isolates (59 E. cloacae, two E. aerogenes, two E. cancerogenus, one E. gergoviae, and four E. sakazakii, currently Cronobacter spp.), and 28 Klebsiella isolates (19 K. oxytoca and 9 K. pneumoniae). Only seven isolates were susceptible to all agents tested, and no resistances to ceftazidime, ciprofloxacin, gentamicin, and chloramphenicol were detected. Most isolates were resistant to amoxicillin/clavulanic acid (74 [58 Enterobacter and 16 Klebsiella]) or to ampicillin (80 [55/25]). Other resistances were less frequent: nitrofurantoin (13 isolates [12/1]), tetracycline (6 [5/1]), co-trimoxazole (3 [3/0]), cefotaxime (1 [1/0]), and streptomycin (2 [1/1]). Multiresistant isolates to two (56 [41/15]), three (10 E. cloacae isolates), four (one E. cloacae and one K. pneumoniae isolate), and five (two E. cloacae isolates) chemotherapeutic agents were also detected. The presence of potential pathogens points to marketed fresh produce, which often is eaten raw, as a risk factor for consumer health. In addition, these results support the usefulness of these bacterial species as indicators of the spreading of antibiotic resistances into the environment, particularly in the food chain, and suggest their role as carriers of resistance determinants from farms to consumers, which may constitute an additional "silent" food safety concern. Therefore, there is a need to improve the hygienic quality of marketed fresh

  7. Computer-aided bone age assessment for ethnically diverse older children using integrated fuzzy logic system

    NASA Astrophysics Data System (ADS)

    Ma, Kevin; Moin, Paymann; Zhang, Aifeng; Liu, Brent

    2010-03-01

    Bone Age Assessment (BAA) of children is a clinical procedure frequently performed in pediatric radiology to evaluate the stage of skeletal maturation based on the left hand x-ray radiograph. The current BAA standard in the US is using the Greulich & Pyle (G&P) Hand Atlas, which was developed fifty years ago and was only based on Caucasian population from the Midwest US. To bring the BAA procedure up-to-date with today's population, a Digital Hand Atlas (DHA) consisting of 1400 hand images of normal children of different ethnicities, age, and gender. Based on the DHA and to solve inter- and intra-observer reading discrepancies, an automatic computer-aided bone age assessment system has been developed and tested in clinical environments. The algorithm utilizes features extracted from three regions of interests: phalanges, carpal, and radius. The features are aggregated into a fuzzy logic system, which outputs the calculated bone age. The previous BAA system only uses features from phalanges and carpal, thus BAA result for children over age of 15 is less accurate. In this project, the new radius features are incorporated into the overall BAA system. The bone age results, calculated from the new fuzzy logic system, are compared against radiologists' readings based on G&P atlas, and exhibits an improvement in reading accuracy for older children.

  8. Energetics of alkali and alkaline earth ion-exchanged zeolite A

    DOE PAGES

    Sun, Hui; Wu, Di; Liu, Kefeng; ...

    2016-06-30

    Alkali and alkaline earth ion-exchanged zeolite A samples were synthesized in aqueous exchange media. They were thoroughly studied by powder X-ray diffraction (XRD), electron microprobe (EMPA), thermogravimetric analysis and differential scanning calorimetry (TG-DSC), and high temperature oxide melt solution calorimetry. The hydration energetics and enthalpies of formation of these zeolite A materials from constituent oxides were determined. Specifically, the hydration level of zeolite A has a linear dependence on the average ionic potential ( Z/r) of the cation, from 0.894 (Rb-A) to 1.317 per TO 2 (Mg-A). The formation enthalpies from oxides (25 °C) range from –93.71 ± 1.77 (K-A)more » to –48.02 ± 1.85 kJ/mol per TO 2 (Li-A) for hydrated alkali ion-exchanged zeolite A, and from –47.99 ± 1.20 (Ba-A) to –26.41 ± 1.71 kJ/mol per TO 2 (Mg-A) for hydrated alkaline earth ion-exchanged zeolite A. As a result, the formation enthalpy from oxides generally becomes less exothermic as Z/r increases, but a distinct difference in slope is observed between the alkali and the alkaline earth series.« less

  9. ECDA of Cased Pipeline Segments

    DOT National Transportation Integrated Search

    2010-06-01

    On June 28, 2007, PHMSA released a Broad Agency Announcement (BAA), DTPH56-07-BAA-000002, seeking white papers on individual projects and consolidated Research and Development (R&D) programs addressing topics on pipeline safety program. Although, not...

  10. Final Report on Improvements to the External Corrosion Direct Assessment (ECDA) Process (WP # 360) Potential Measurements on Paved Areas (Project #243)

    DOT National Transportation Integrated Search

    2010-06-01

    On June 28, 2007, PHMSA released a Broad Agency Announcement (BAA), DTPH56- 07-BAA-000002, seeking white papers on individual projects and consolidated Research and Development (R&D) programs addressing topics on their pipeline safety program. Althou...

  11. Immune Analysis of Brisbane and California H1N1 in Human Sera and the MIMIC System, and Correlating a H1N1 Pandemic Influenza Clinical Trial with a Clinical Trial in a Test Tube

    DTIC Science & Technology

    2013-02-15

    09-C-0119 BAA09-31 & BAA-10-55 Final Report Date of Proposal: Prepared by Sanofi Pasteur VaxDesign Campus...Sciences, seasonal influenza trivalent intramuscular (TIV-IM) or intradermal (TIV-ID) vaccines, and a quadrivalent influenza vaccine (QIV) from Sanofi . We

  12. Fortifying fresh human milk with commercial powdered human milk fortifiers does not affect bacterial growth during 6 hours at room temperature.

    PubMed

    Telang, Sucheta; Berseth, Carol Lynn; Ferguson, Paul W; Kinder, Julie M; DeRoin, Mark; Petschow, Bryon W

    2005-10-01

    To evaluate the growth of resident aerobic mesophilic flora and added Enterobacter sakazakii in fresh, unfortified human milk; fresh human milk fortified with two commercial powdered fortifiers differing in iron content; and infant formula prepared from powder. Eight mothers provided preterm breast milk samples. Breast milk samples were divided into three aliquots: unfortified, fortified with fortifier containing 1.44 mg iron/14 kcal, and fortified with fortifier containing 0.4 mg iron/14 kcal. Aliquots of formula were prepared. Breast milk and formula aliquots were divided into two test samples. Half were inoculated with low amounts of E sakazakii; half were not. All test samples were maintained at room temperature (22 degrees C), serially diluted, and plated onto agars after 0, 2, 4, and 6 hours. Plates were incubated at 35 degrees C and enumerated. Data were analyzed using repeated measures analysis of variance. P<.05 was considered significant. There were no differences in colony counts of aerobic bacteria among uninoculated or among inoculated human milk samples at any time; counts did not increase significantly over 6 hours. There were no differences in colony counts of E sakazakii among inoculated human milk samples at any time; counts did not increase significantly over 6 hours. Aerobic bacteria and E sakazakii colony counts from infant formula did not increase significantly over 6 hours. During 6 hours at 22 degrees C, fresh human milk and formula had negligible bacterial growth; fortifying human milk with powdered fortifiers did not affect bacterial growth.

  13. eNOS gene T786C, G894T and 4a4b polymorphisms and male infertility susceptibility: a meta-analysis.

    PubMed

    Chang, J; Pan, F; Tang, Q; Wu, W; Chen, M; Lu, C; Ding, H; Hu, L; Chen, D; Xia, Y; Wang, X

    2017-05-01

    The association between polymorphism of eNOS and male infertility in several studies was controversial. To explore a more precise estimation of the association, a meta-analysis of eight case-control studies, including 1,968 cases and 1,539 controls, were selected. The meta-analysis was conducted by calculating the pooled odds ratio (OR) with a 95% confidence interval (95% CI). Overall, the association between T786C and risk of male infertility was obvious (TC vs. TT: OR, 1.20; 95% CI, 1.01-1.42; CC vs. TT: OR, 3.37; 95% CI, 1.65-6.87; TC/CC vs. TT: OR, 1.47; 95% CI, 1.25-1.73; CC vs. OR, 3.18; 95% CI, 1.54-6.56; TC vs. TT: OR, 1.65; 95% CI, 1.27-2.03). However, no overall association was observed between the other two polymorphisms of eNOS (G894T and 4a4b) and male infertility. Stratified analysis showed that significantly strong association between T786C polymorphism and semen quality was present in all three types of male infertility (azoospermia, oligozoospermia and asthenozoospermia). In the subgroup analysis based on ethnicity, both T786C and 4a4b could influence the risk of male infertility in Asian and Caucasian. Further studies of polymorphisms of eNOS with their biological functions are needed to understand the role in the development of male infertility. © 2016 Blackwell Verlag GmbH.

  14. Evaluation of Escherichia coli biotype 1 as a surrogate for Escherichia coli O157:H7 for cooking, fermentation, freezing, and refrigerated storage in meat processes.

    PubMed

    Keeling, Carisa; Niebuhr, Steven E; Acuff, Gary R; Dickson, James S

    2009-04-01

    Five Escherichia coli biotype I isolates were compared with E. coli O157:H7 under four common meat processing conditions. The processes that were evaluated were freezing, refrigerating, fermentation, and thermal inactivation. For each study, at least one surrogate organism was not statistically different when compared with E. coli O157:H7. However, the four studies did not consistently show the same isolate as having this agreement. The three studies that involved temperature as a method of controlling or reducing the E. coli population all had at least one possible surrogate in common. In the fermentation study, only one isolate (BAA-1429) showed no statistical difference when compared with E. coli O157:H7. However, the population reductions that were observed indicated the isolates BAA-1427 and BAA-1431 would overestimate the surviving E. coli O157:H7 population in a fermented summer sausage. When all of the data from all of the surrogates were examined, it was found that isolates BAA-1427, BAA-1429, and BAA-1430 would be good surrogates for all four of the processes that were examined in this study. There was no statistical difference noted between these three isolates and E. coli O157:H7 in the refrigeration study. These isolates resulted in smaller population reductions than did E. coli O157:H7 in the frozen, fermentation, and thermal inactivation studies. This would indicate that these isolates would overpredict the E. coli O157:H7 population in these three instances. This overprediction results in an additional margin of safety when using E. coli biotype 1 as a surrogate.

  15. An Innovative Baccalaureate Degree: Applied versus Traditional

    ERIC Educational Resources Information Center

    Arney, Janna B.; Hardebeck, Suzanne; Estrada, Joselito; Permenter, Vivian

    2006-01-01

    The bachelor of applied arts and sciences (BAAS) degree is a baccalaureate program designed to meet the needs of nontraditional students by allowing technical hours to be transferred for credit to a baccalaureate degree. To determine if the university was positively serving the needs of its constituents, salaries of BAAS graduates were compared to…

  16. Effect of fluxing treatment on the properties of Fe66Co15Mo1P7.5C5.5B2Si3 bulk metallic glass by water quenching

    NASA Astrophysics Data System (ADS)

    Li, Jin-Feng; Wang, Xin; Liu, Xue; Zhao, Shao-Fan; Yao, Ke-Fu

    2018-01-01

    The effect of fluxing treatment on the properties of Fe66Co15Mo1P7.5C5.5B2Si3bulk amorphous alloy (BAA) has been investigated. Prepared by a combination method of flux treatment and water quenching, the Fe66Co15Mo1P7.5C5.5B2Si3 BAA exhibits better glass-forming ability, thermal stability, soft magnetic properties and ductility than those of the one prepared by direct water quenching. This indicates that fluxing treatment can play a potential role in improving the properties of Fe-based BAA due to the effective elimination of the impurities within the alloy.

  17. Electronic Reverse Auctions in the Federal Government

    DTIC Science & Technology

    2007-12-01

    William R. Gates _____________________________________ Peter J. Coughlan _____________________________________ Robert N. Beck ...AND ACRONYMS BAA Buy American Act BPA Blanket Purchase Agreement CBE Competitive Bidding Event CCR Central Contractor Registration CECOM...BUY AMERICAN ACT Even if a buyer employs e-RAs to determine the price of an item, the regulations such as the Buy American Act ( BAA ) still apply

  18. Survey on Classifying Human Actions through Visual Sensors

    DTIC Science & Technology

    2011-04-08

    International Conference on Automatic Face and Gesture Recognition, 2008, pp. 1-6, doi:10.1109/AFGR.2008.4813416. [47] Herrera, A., Beck , A., Bell, D...Announcement, DARPA- BAA -10-53, 2010 www.darpa.mil/tcto/docs/DARPA_ME_BAA-10-53_Mod1.pdf [84] Del Rose, M., Stein, J., “Survivability on the ART Robotic

  19. Growth-promoting technologies decrease the carbon footprint, ammonia emissions, and costs of California beef production systems.

    PubMed

    Stackhouse, K R; Rotz, C A; Oltjen, J W; Mitloehner, F M

    2012-12-01

    Increased animal performance is suggested as one of the most effective mitigation strategies to decrease greenhouse gas (GHG) and ammonia (NH(3)) emissions from livestock production per unit of product produced. Little information exists, however, on the effects of increased animal productivity on the net decrease in emission from beef production systems. A partial life cycle assessment (LCA) was conducted using the Integrated Farm System Model (IFSM) to estimate GHG and NH(3) emissions from representative beef production systems in California that use various management technologies to enhance animal performance. The IFSM is a farm process model that simulates crop growth, feed production, animal performance, and manure production and handling through time to predict the performance, economics, and environmental impacts of production systems. The simulated beef production systems compared were 1) Angus-natural, with no use of growth-enhancing technologies, 2) Angus-implant, with ionophore and growth-promoting implant (e.g., estrogen/trenbolone acetate-based) application, 3) Angus-ß2-adrenergic agonists (BAA; e.g., zilpaterol), with ionophore, growth-promoting implant, and BAA application, 4) Holstein-implant, with growth implant and ionophore application, and 5) Holstein-BAA, with ionophore, growth implant, and BAA use. During the feedlot phase, use of BAA decreased NH(3) emission by 4 to 9 g/kg HCW, resulting in a 7% decrease in NH(3) loss from the full production system. Combined use of ionophore, growth implant, and BAA treatments decreased NH(3) emission from the full production system by 14 g/kg HCW, or 13%. The C footprint of beef was decreased by 2.2 kg carbon dioxide equivalent (CO(2)e)/kg HCW using all the growth-promoting technologies, and the Holstein beef footprint was decreased by 0.5 kg CO(2)e/kg HCW using BAA. Over the full production systems, these decreases were relatively small at 9% and 5% for Angus and Holstein beef, respectively. The growth

  20. An online real-time DICOM web-based computer-aided diagnosis system for bone age assessment of children in a PACS environment

    NASA Astrophysics Data System (ADS)

    Ma, Kevin C.; Zhang, Aifeng; Moin, Paymann; Fleshman, Mariam; Vachon, Linda; Liu, Brent; Huang, H. K.

    2009-02-01

    Bone age assessment is a radiological procedure to evaluate a child's bone age based on his or her left-hand x-ray image. The current standard is to match patient's hand with Greulich & Pyle hand atlas, which is outdated by 50 years and only uses subjects from one region and one ethnicity. To improve bone age assessment accuracy for today's children, an automated race- and gender-specific bone age assessment (BAA) system has been developed in IPILab. 1390 normal left-hand x-ray images have been collected at Children's Hospital of Los Angeles (CHLA) to form the digital hand atlas (DHA). DHA includes both male and female children of ages one to eighteen and of four ethnic groups: African American, Asian American, Caucasian, and Hispanic. In order to apply DHA and BAA CAD into a clinical environment, a web-based BAA CAD system and graphical user interface (GUI) has been implemented in Women and Children's Hospital at Los Angeles County (WCH-LAC). A CAD server has been integrated in WCH's PACS environment, and a clinical validation workflow has been designed for radiologists, who compare CAD readings with G&P readings and determine which reading is more suited for a certain case. Readings are logged in database and analyzed to assess BAA CAD performance in a clinical setting. The result is a successful installation of web-based BAA CAD system in a clinical setting.

  1. Concomitant presence of endothelial nitric oxide 894T and angiotensin II-converting enzyme D alleles are associated with diabetic nephropathy in a Kurdish population from Western Iran.

    PubMed

    Rahimi, Zohreh; Vaisi-Raygani, Asad; Rahimi, Ziba; Parsian, Abbas

    2012-02-01

    The present study investigated the influence of insertion (I)/deletion (D) polymorphism of the angiotensin II-converting enzyme (ACE) gene in combination with endothelial nitric oxide (eNOS) G894T polymorphism on the predisposition to diabetic nephropathy (DN). Using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP) method, the ACE and eNOS polymorphisms were genotyped in 72 microalbuminuric, 68 macroalbuminuric and 72 normoalbuinuric type 2 diabetes mellitus (T2DM) patients from Western Iran. The presence of eNOS T or ACE D allele was not associated with increased risk of macroalbuminuria (odds ratio (OR) = 1.36, P = 0.27 and OR = 1.6, P = 0.062, respectively). However, in the presence of both alleles there was a trend towards increased risk of macroalbuminuria (fivefold, P = 0.05). Our study indicates that the concomitant presence of both ACE D and eNOS T alleles tends to be associated with an elevation risk of macroalbuminuria compared with the presence of each polymorphism alone. This risk could be attributed to the increasing activity of ACE and angiotensin II level in the presence of D allele and decreasing NO production in the presence of T allele accelerating diabetic nephropathy. © 2011 The Authors. Nephrology © 2011 Asian Pacific Society of Nephrology.

  2. Enzymatic Properties of an Alkaline and Chelator Resistant alpha-amylase from the Alkaliphilic Bacillus sp. Isolate L1711

    NASA Technical Reports Server (NTRS)

    Bernhardsdotter, Eva C. M. J.; Pusey, Marc L.; Ng, Joseph D.; Garriott, Owen K.

    2004-01-01

    An alkaliphilic amylase producing bacterium, Bacillus sp. strain L 711, was selected among 13 soda lakes isolates. When grown at pH 10.5 and 37 C, strain L711 produced multiple forms of amylases in the culture broth. One of these, BAA, was purified from the culture supernatant by QAE column chromatography and preparative native gel electrophoresis. The molecular weight of BAA was determined to be 51 kDa by denaturing gel electrophoresis. The pH optima for activity below and above 40 C were 9.5 - 10.0 and 7.0 - 7.5 respectively. BAA was stable in the pH range 6-11 and was completely inactivated at 55 C. The thermostability was not increased in the presence of Ca(2+). The enzyme was strongly inhibited by Ca(2+), Zn(2+), Mg(2+), Mn(2+), Ba(2+) and Cu(2+), whereas the presence of Na(+), Co(2+) and EDTA (10 mM) enhanced enzymatic activity. The K(sub m), and specific activity of BAA on soluble starch were 1.9 mg/ml and 18.5 U/mg respectively. The main end products of hydrolysis were maltotetraose, maltose and glucose.

  3. Enzymatic Properties of an Alkaline and Chelator Resistant Proportional to alpha-Amylase from the Alkaliphilic Bacillus sp. Isolate L1711

    NASA Technical Reports Server (NTRS)

    Bernhardsdotter, Eva C. M. J.; Pusey, Marc L.; Ng, Joseph D.; Garriott, Owen K.

    2004-01-01

    An alkaliphilic amylase producing bacterium, Bacillus sp. strain L1711, was selected among 13 soda lakes isolates. When grown at pH 10.5 and 370 C, strain L1711 produced multiple forms of amylases in the culture broth. One of these, BAA, was purified from the culture supernatant by QAE column chromatography and preparative native gel electrophoresis. The molecular weight of BAA was determined to be 51 kDa by denaturing gel electrophoresis. The pH optima for activity below and above 40 C were 9.5-10.0 and 7.0-7.5 respectively. BAA was stable in the pH range 6-11 and was completely inactivated at 55?C. The thermostability was not increased in the presence of Ca(2+). The enzyme was strongly inhibited by Ca(2+), Zn(2+), Mg(2+), Mn(2+), Ba(2+) and Cu(2+), whereas the presence of Na(+), Co2+ and EDTA (10 mM) enhanced enzymatic activity. The K(sub m) and specific activity of BAA on soluble starch were 1.9 mg/ml and 18.5 U/mg respectively. The main end products of hydrolysis were maltotetraose, maltose and glucose .

  4. Congenital branchial apparatus malformation in a Haflinger colt.

    PubMed

    David, Florent; Savard, Claudine; Drolet, Richard; Alexander, Kate; Pang, Daniel S J; Laverty, Sheila

    2008-01-01

    To report the diagnosis and treatment of a branchial apparatus anomaly (BAA) associated with a mandibular malformation in a foal. Clinical report. Haflinger foal. A 6-day-old foal had a fluctuating cystic mass in the pharyngeal (throatlatch) region, which changed in appearance after ingestion of milk. Upper airway endoscopy and diagnostic imaging (ultrasonography, radiography, computed tomography) permitted identification of the anatomic location of a communicating tract between the lumen of the cystic mass and the pharynx. The mass was surgically removed and communication with the pharynx ligated. Histologic appearance of this mass was consistent with a branchial cyst or sinus. The mandibular malformation was managed conservatively. Surgical resection of a third branchial sinus resulted in an excellent functional and cosmetic outcome. There was no evidence of any mandibular deformity 2 years later. BAA may induce secondary mandibular deformation in utero and may cause respiratory compromise postpartum. Careful surgical dissection and removal of BAA resulted in an excellent outcome. BAAs should be included in the differential diagnosis of a throatlatch region mass in equine neonates. Complete surgical excision is recommended and full recovery of any associated mandibular deformity may be anticipated without additional treatment in very young patients.

  5. Autonomous Control Modes and Optimized Path Guidance for Shipboard Landing in High Sea States

    DTIC Science & Technology

    2016-01-29

    Research in Sea-Based Aviation ONR #BAA12-SN-028 CDRL A001 DISTRIBUTION STATEMENT A: Distribution Approved for public release; distribution...is performed under the Office of Naval Research program on Basic and Applied Research in Sea- Based Aviation (ONR BAA12-SN-0028). This project...addresses the Sea Based Aviation (SBA) initiative in Advanced Handling Qualities for Rotorcraft. Landing a rotorcraft on a moving ship deck and under the

  6. Priming dose of phenylhydrazine protects against hemolytic and lethal effects of 2-butoxyethanol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Palkar, Prajakta S.; Philip, Binu K.; Reddy, Ramesh N.

    2007-11-15

    Protection against a high dose of a toxicant by prior exposure to another toxicant is called heteroprotection. Our objective was to establish a heteroprotection model in RBCs. Female Sprague Dawley rats treated with an LD90 dose of 2-butoxyethanol (BE, 1500 mg/kg in water, 5 ml/kg po) 14 days after priming with 0.9% NaCl suffered 90% mortality by 15 days, whereas all rats receiving the LD90 dose of BE 14 days after priming with phenylhydrazine (PHZ, 125 mg/kg in 0.9% NaCl, 3 ml/kg po) survived. Hematocrit decreased from normal 45% to 24% by day 3 after PHZ priming and improved thereafter.more » Increasing the time interval between the priming and LD90 dose to 21 days abolished the heteroprotection. RBCs obtained on days 7 and 14 after PHZ priming unlike those on day 21 were resilient to the hemotoxic metabolite of BE, butoxyacetic acid (BAA). Unaltered hepatic alcohol and aldehyde dehydrogenase activities upon PHZ priming suggested that bioactivation of BE to BAA was unaffected. Lower renal (6 and 12 h) and hepatic (12 h) BAA levels and 3 fold higher excretion of BAA in PHZ-primed rat urine suggested a protective role of toxicokinetics. Higher erythropoietin, reticulocytes, and resiliency of PHZ-primed rat RBCs indicated that newly formed RBCs are resilient to hemolytic BAA. The antioxidant levels in the PHZ-primed rat RBCs did not indicate a protective role in heteroprotection. In conclusion, the resistance of PHZ-primed rats against BE-induced hemotoxicity and lethality is mediated by a combination of altered toxicokinetics, robust erythropoiesis, and resiliency of new RBCs.« less

  7. Early and late effects of coumarin therapy started before percutaneous coronary intervention: Clinical, angiographic and cost-effective outcome of the Balloon Angioplasty and Anticoagulation Study (BAAS).

    PubMed

    Ten Berg, J M; Kelder, J C; Suttorp, M J; Mast, E G; Bal, E T; Ernst, J M P G; Plokker, H W M

    2002-05-01

    Coronary angioplasty frequently creates a thrombogenic surface with subsequent mural thrombosis that may lead to acute complications and possibly stimulates the development of restenosis. Whether coumarins can prevent these complications is unclear. In the Balloon Angioplasty and Anticoagulation Study (BAAS), the effect of coumarins started before the procedure on early and late outcome was studied. Patients were randomised to aspirin only or to aspirin plus coumarins. Half of the patients were randomised to undergo six-month angiographic follow-up. Study medication was started one week before coronary angioplasty and the target international normalised ratio (INR) was 2.1-4.8 during angioplasty and six-month follow-up. 'Optimal' anticoagulation was defined as an INR in the target range for at least 70% of the follow-up time. In addition, cost-effectiveness of coumarin treatment was measured. At one year death, myocardial infarction, target-lesion revascularisation and stroke were observed in 14.3% of the 530 patients randomised to aspirin plus coumarin versus in 20.3% of the 528 patients randomised to aspirin alone (relative risk 0.71; 95% CI 0.54-0.93). The incidence of major bleedings and false aneurysms during hospitalisation was 3.2% and 1.0%, respectively, (relative risk 3.39; 95% CI 1.26-9.11). Optimal anticoagulation was an independent predictor of late thrombotic events (relative risk, 0.33; 95% CI, 0.19-0.57). Quantitative coronary analysis was performed of 301 lesions in the ASA group and of 297 lesions in the coumarin group. At six months, the minimal luminal diameter was similar in the ASA and coumarin group. However, optimal anticoagulation was an independent predictor of angiographic outcome at six months. Optimal anticoagulation led to a 0.21 mm (95% CI: 0.05-0.37) larger MLD as compared with suboptimal anticoagulation whereas aspirin use led to a 0.12 mm (95% CI -0.28-0.04) smaller MLD. When including all costs, the savings associated with coumarin

  8. SiC Deep Ultraviolet Avalanche Photodetectors

    DTIC Science & Technology

    2010-10-01

    L. Beck 1.00 Xiaogang Bai 1.00 4.00FTE Equivalent: 4Total Number: Names of Faculty Supported National Academy MemberPERCENT_SUPPORTEDNAME Joe...robust APDs capable of high gain or Geiger mode operation. Since the release of BAA 06-14, the applications originally discussed were de-emphasized...the applications identified in the original DUVAP BAA , or those for general DoD or industrial use. While GE will continue to evaluate potential

  9. High Resolution Optical Imaging through the Atmosphere

    DTIC Science & Technology

    1989-12-28

    34Iterative Blind Deconvolution Method and its Applications’, Opt. Lett., 13, p.54 7 . Fienup, J.R. 1978, Opt. Lett., 3, 27. Karovska , M., Nisenson, P., and...Noyes, R. (1987), ’High Angular Resolution Speckle Imaging of Alpha Ori", BAAS, Vol.19, No. 2. Karovska , M., Koechlin, L., Nisenson, P., Papaliolios...Publishers. Karovska , M., Nisenson, P., Papaliolios, C., Stendley, C. (1989), "High Angular Speckle Observations of SN1987A. Days 40-580.", BAAS, Vol

  10. Monohydroxylated polycyclic aromatic hydrocarbons influence spicule formation in the early development of sea urchins (Hemicentrotus pulcherrimus).

    PubMed

    Suzuki, Nobuo; Ogiso, Shouzo; Yachiguchi, Koji; Kawabe, Kimi; Makino, Fumiya; Toriba, Akira; Kiyomoto, Masato; Sekiguchi, Toshio; Tabuchi, Yoshiaki; Kondo, Takashi; Kitamura, Kei-ichiro; Hong, Chun-Sang; Srivastav, Ajai K; Oshima, Yuji; Hattori, Atsuhiko; Hayakawa, Kazuichi

    2015-05-01

    We previously demonstrated that monohydroxylated polycyclic aromatic hydrocarbons (OHPAHs), which are metabolites of polycyclic aromatic hydrocarbons (PAHs), act on calcified tissue and suppress osteoblastic and osteoclastic activity in the scales of teleost fish. The compounds may possibly influence other calcified tissues. Thus, the present study noted the calcified spicules in sea urchins and examined the effect of both PAHs and OHPAHs on spicule formation during the embryogenesis of sea urchins. After fertilization, benz[a]anthracene (BaA) and 4-hydroxybenz[a]anthracene (4-OHBaA) were added to seawater at concentrations of 10(-8) and 10(-7) M and kept at 18 °C. The influence of the compound was given at the time of the pluteus larva. At this stage, the length of the spicule was significantly suppressed by 4-OHBaA (10(-8) and 10(-7) M). BaA (10(-7) M) decreased the length of the spicule significantly, while the length did not change with BaA (10(-8) M). The expression of mRNAs (spicule matrix protein and transcription factors) in the 4-OHBaA (10(-7) M)-treated embryos was more strongly inhibited than were those in the BaA (10(-7) M)-treated embryos. This is the first study to demonstrate that OHPAHs suppress spicule formation in sea urchins. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Conformational analysis, tautomerization, IR, Raman, and NMR studies of benzyl acetoacetate

    NASA Astrophysics Data System (ADS)

    Tayyari, Sayyed Faramarz; Naghavi, Farnaz; Pojhan, Sahar; McClurg, Ryan W.; Sammelson, Robert E.

    2011-02-01

    A complete conformational analysis of the keto and enol forms of benzyl acetoacetate (BAA), a β-dicarbonyl compound, was carried out by ab initio calculations, at the density functional theory (DFT) level. By inspection of all possible conformers and tautomers, 22 stable cis-enol, 28 stable trans-enol, and five keto conformers were obtained. Among all stable cis-enol forms only six of them are engaged in intramolecular hydrogen bond. The hydrogen bond strength of the most stable conformer of BAA is compared with that of acetylacetone (AA) and dimethyl oxaloacetate (DMOA). Harmonic vibrational frequencies of the most stable enol and keto forms and their deuterated analogues were also calculated and compared with the experimental data. According to the theoretical calculations, the hydrogen bond strength of the most stable enol conformer of BAA is 56.7 kJ/mol (calculated at the B3LYP/6-311++G ∗∗ level), about 10 kJ/mol less than that of AA. This weakening of hydrogen bond is consistent with the spectroscopic results. NMR studies indicate that BAA exists mainly as a keto tautomer in all considered solutions. The Gibbs energies for keto/enol tautomerization were calculated at the B3LYP level, with several basis sets, in both gas phase and CH 3CN solution (using PCM model), for the most stable enol and keto conformers.

  12. Spider Silk Glue Proteins BAA 8.1

    DTIC Science & Technology

    2017-09-14

    protein expression. 3. The genes were then used in flask fermentation expression studies to insure that protein of the correct size was being...one of the lengths (3X, roughly a 140kD protein) for initial studies. We were able to detect protein production in these fermentations but we saw

  13. NOS3 gene polymorphisms and exercise hemodynamics in postmenopausal women.

    PubMed

    Hand, B D; McCole, S D; Brown, M D; Park, J J; Ferrell, R E; Huberty, A; Douglass, L W; Hagberg, J M

    2006-12-01

    We tested whether the G894T and T-786C NOS3 polymorphisms were associated with exercise cardiovascular (CV) hemodynamics in sedentary, physically active, and endurance-trained postmenopausal women. CV hemodynamic parameters including heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressures and cardiac output (Q), as determined by acetylene rebreathing, stroke volume (SV), arteriovenous oxygen difference (a-vO2 diff), and total peripheral resistance (TPR) were measured during submaximal (40, 60, 80 %) and maximal (approximately 100 % VO2max) exercise. NOS3 G894T genotype was not significantly associated, either independently or interactively with habitual physical activity (PA) level, with SBP, Q, TPR, or a-vO2 diff during submaximal or maximal exercise. However, NOS3 894T non-carriers had a higher submaximal exercise HR than NOS3 894T allele carriers (120 +/- 2 vs. 112 +/- 2 beats/min, p = 0.007). NOS3 894T allele carriers had a higher SV than 894T non-carriers (78 +/- 2 vs. 72 +/- 2 ml/beat, p = 0.03) during submaximal exercise. NOS3 894T non-carriers also had a higher maximal exercise HR averaged across habitual PA groups than T allele carrier women (165 +/- 2 vs. 158 +/- 2 beats/min, p = 0.04). NOS3 894T allele carriers also tended to have a higher SV during maximal exercise than 894T non-carriers (70 +/- 2 vs. 64 +/- 2 ml/beat, p = 0.08). NOS3 T-786C genotype was not significantly associated, either independently or interactively, with any of the CV hemodynamic measures during submaximal or maximal exercise. These results suggest an association of NOS3 G894T genotype with submaximal and maximal exercise CV hemodynamic responses, especially HR, in postmenopausal women.

  14. Learn About Cronobacter Infection

    MedlinePlus

    ... Emergency Preparedness & Response Environmental Health Healthy Living Injury, Violence & Safety Life Stages & Populations Travelers’ Health Workplace Safety & Health Features Media Sign up for Features Get Email Updates To ...

  15. Science and sociability: women as audience at the British Association for the Advancement of Science, 1831-1901.

    PubMed

    Higgitt, Rebekah; Withers, Charles W J

    2008-03-01

    This essay recovers the experiences of women at the meetings of the British Association for the Advancement of Science (BAAS) from its founding in 1831 to the end of the Victorian era. It aims to add to research on women in science by reconsidering the traditional role of women as consumers rather than producers of knowledge and to that on science popularization by focusing on audience experience rather than on the aims and strategies of popularizers. The essay argues that, in various ways, the ubiquitous and visible female audience came to define the BAAS audience and "the public" for science more generally. The women who swelled the BAAS audiences were accepted as a social element within the meetings even as they were regarded critically as scientific participants. Portrayed as passive and nonscientific, women allowed the male scientific elites to distance themselves from their audiences. Arguing from diary and other evidence, we present examples that complicate existing notions of audiences for science as necessarily active.

  16. Mycobacterium minnesotense sp. nov., a photochromogenic bacterium isolated from sphagnum peat bogs.

    PubMed

    Hannigan, Geoffrey D; Krivogorsky, Bogdana; Fordice, Daniel; Welch, Jacqueline B; Dahl, John L

    2013-01-01

    Several intermediate-growing, photochromogenic bacteria were isolated from sphagnum peat bogs in northern Minnesota, USA. Acid-fast staining and 16S rRNA gene sequence analysis placed these environmental isolates in the genus Mycobacterium, and colony morphologies and PCR restriction analysis patterns of the isolates were similar. Partial sequences of hsp65 and dnaJ1 from these isolates showed that Mycobacterium arupense ATCC BAA-1242(T) was the closest mycobacterial relative, and common biochemical characteristics and antibiotic susceptibilities existed between the isolates and M. arupense ATCC BAA-1242(T). However, compared to nonchromogenic M. arupense ATCC BAA-1242(T), the environmental isolates were photochromogenic, had a different mycolic acid profile and had reduced cell-surface hydrophobicity in liquid culture. The data reported here support the conclusion that the isolates are representatives of a novel mycobacterial species, for which the name Mycobacterium minnesotense sp. nov. is proposed. The type strain is DL49(T) (=DSM 45633(T) = JCM 17932(T) = NCCB 100399(T)).

  17. Finding evolved stars in the inner Galactic disk with Gaia

    NASA Astrophysics Data System (ADS)

    Quiroga-Nuñez, L. H.; van Langevelde, H. J.; Pihlström, Y. M.; Sjouwerman, L. O.; Brown, A. G. A.

    2018-04-01

    The Bulge Asymmetries and Dynamical Evolution (BAaDE) survey will provide positions and line-of-sight velocities of ~20, 000 evolved, maser bearing stars in the Galactic plane. Although this Galactic region is affected by optical extinction, BAaDE targets may have Gaia cross-matches, eventually providing additional stellar information. In an initial attempt to cross-match BAaDE targets with Gaia, we have found more than 5,000 candidates. Of these, we may expect half to show SiO emission, which will allow us to obtain velocity information. The cross-match is being refined to avoid false positives using different criteria based on distance analysis, flux variability, and color assessment in the mid- and near-IR. Once the cross-matches can be confirmed, we will have a unique sample to characterize the stellar population of evolved stars in the Galactic bulge, which can be considered fossils of the Milky Way formation.

  18. An update on the Boston Marathon as a research laboratory.

    PubMed

    Panza, Gregory A; Taylor, Beth A; Zaleski, Amanda L; Thompson, Paul D

    2015-07-01

    The Boston Athletic Association's annual marathon, also referred to as BAA in this article, continues to be a source of subjects for exercise and endurance performance research. We performed a systematic literature review of BAA studies published in the 7 years since our prior report. We identified 20 articles published from January 2008 to February 2015. Nine were related to cardiology; six were related to exercise physiology; four were related to metabolism; and one was related to marathon qualifying times. As in our prior, report cardiovascular studies remained the dominant topic, but with risk factors for atherosclerosis and thrombosis as the present focus. Cardiac issues remain the largest subject area for BAA studies, but with more emphasis on the effect of prolonged exercise on atherosclerotic and thrombotic risk factors. This shift is associated with an increase in marathon participation by older, recreational runners at increased risk of cardiac complications due to exercise.

  19. Escherichia coli and other Enterobacteriaceae: Food poisoning and health effects

    USDA-ARS?s Scientific Manuscript database

    The family Enterobactericeae consists of rod-shaped, Gram-negative, facultatively anaerobic, non-spore forming bacteria and also includes the food-borne pathogens, Cronobacter spp., Escherichia coli, Salmonella enterica, Shigella spp., and Yersinia spp. Illness caused by these pathogens is acquired...

  20. Prospects for a Novel Ultrashort Pulsed Laser Technology for Pathogen Inactivation

    DTIC Science & Technology

    2012-07-06

    and Listeria [3-11]. The USP laser technology has the following advantages over the current methods of disinfection of pathogens: (1) With... Listeria monocytogenes Gram positive 10 3 Enterobacter Sakazakii Gram negative 10 3 (2) Existing disinfection methods such as irradiation of ultraviolet

  1. 7 CFR 51.894 - Weak.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... content, inferior flavor, or are of poor keeping quality. [36 FR 9126, May 20, 1971. Redesignated at 42 FR...

  2. 7 CFR 51.894 - Weak.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... content, inferior flavor, or are of poor keeping quality. [36 FR 9126, May 20, 1971. Redesignated at 42 FR...

  3. 7 CFR 51.894 - Weak.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... have relatively low sugar content, inferior flavor, or are of poor keeping quality. [36 FR 9126, May 20...

  4. 7 CFR 51.894 - Weak.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... have relatively low sugar content, inferior flavor, or are of poor keeping quality. [36 FR 9126, May 20...

  5. 5 CFR 894.101 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... enrollee in a regular parent-child relationship; or (iv) A recognized natural child. (2) This definition... if the child lives with the enrollee or receives financial support from the enrollee. Regular parent-child relationship means that the enrollee is exercising parental authority, responsibility, and control...

  6. 5 CFR 894.101 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...,” “your,” etc., refer, as appropriate, to the applicant or enrollee. Acquiring an eligible child means one of the following: (1) Birth of a child; (2) Adoption of a child; (3) Acquisition of a foster child as... a regular parent-child relationship; (5) Establishment of a recognized natural child; (6) Residence...

  7. 7 CFR 51.894 - Weak.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... content, inferior flavor, or are of poor keeping quality. [36 FR 9126, May 20, 1971. Redesignated at 42 FR...

  8. Bone Tissue Response to Porous and Functionalized Titanium and Silica Based Coatings

    PubMed Central

    Chaudhari, Amol; Braem, Annabel; Vleugels, Jozef; Martens, Johan A.; Naert, Ignace; Cardoso, Marcio Vivan; Duyck, Joke

    2011-01-01

    Background Topography and presence of bio-mimetic coatings are known to improve osseointegration. The objective of this study was to evaluate the bone regeneration potential of porous and osteogenic coatings. Methodology Six-implants [Control (CTR); porous titanium coatings (T1, T2); thickened titanium (Ti) dioxide layer (TiO2); Amorphous Microporous Silica (AMS) and Bio-active Glass (BAG)] were implanted randomly in tibiae of 20-New Zealand white rabbits. The animals were sacrificed after 2 or 4 weeks. The samples were analyzed histologically and histomorphometrically. In the initial bone-free areas (bone regeneration areas (BRAs)), the bone area fraction (BAF) was evaluated in the whole cavity (500 µm, BAF-500), in the implant vicinity (100 µm, BAF-100) and further away (100–500 µm, BAF-400) from the implant. Bone-to-implant contact (BIC-BAA) was measured in the areas where the implants were installed in contact to the host bone (bone adaptation areas (BAAs)) to understand and compare the bone adaptation. Mixed models were used for statistical analysis. Principal Findings After 2 weeks, the differences in BAF-500 for different surfaces were not significant (p>0.05). After 4 weeks, a higher BAF-500 was observed for BAG than CTR. BAF-100 for AMS was higher than BAG and BAF-400 for BAG was higher than CTR and AMS. For T1 and AMS, the bone regeneration was faster in the 100-µm compared to the 400-µm zone. BIC-BAA for AMS and BAG was lower after 4 than 2 weeks. After 4 weeks, BIC-BAA for BAG was lower than AMS and CTR. Conclusions BAG is highly osteogenic at a distance from the implant. The porous titanium coatings didn't stimulate bone regeneration but allowed bone growth into the pores. Although AMS didn't stimulate higher bone response, it has a potential of faster bone growth in the vicinity compared to further away from the surface. BIC-BAA data were inconclusive to understand the bone adaptation. PMID:21935382

  9. Real-time out-of-plane artifact subtraction tomosynthesis imaging using prior CT for scanning beam digital x-ray system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Meng, E-mail: mengwu@stanford.edu; Fahrig, Rebecca

    2014-11-01

    Purpose: The scanning beam digital x-ray system (SBDX) is an inverse geometry fluoroscopic system with high dose efficiency and the ability to perform continuous real-time tomosynthesis in multiple planes. This system could be used for image guidance during lung nodule biopsy. However, the reconstructed images suffer from strong out-of-plane artifact due to the small tomographic angle of the system. Methods: The authors propose an out-of-plane artifact subtraction tomosynthesis (OPAST) algorithm that utilizes a prior CT volume to augment the run-time image processing. A blur-and-add (BAA) analytical model, derived from the project-to-backproject physical model, permits the generation of tomosynthesis images thatmore » are a good approximation to the shift-and-add (SAA) reconstructed image. A computationally practical algorithm is proposed to simulate images and out-of-plane artifacts from patient-specific prior CT volumes using the BAA model. A 3D image registration algorithm to align the simulated and reconstructed images is described. The accuracy of the BAA analytical model and the OPAST algorithm was evaluated using three lung cancer patients’ CT data. The OPAST and image registration algorithms were also tested with added nonrigid respiratory motions. Results: Image similarity measurements, including the correlation coefficient, mean squared error, and structural similarity index, indicated that the BAA model is very accurate in simulating the SAA images from the prior CT for the SBDX system. The shift-variant effect of the BAA model can be ignored when the shifts between SBDX images and CT volumes are within ±10 mm in the x and y directions. The nodule visibility and depth resolution are improved by subtracting simulated artifacts from the reconstructions. The image registration and OPAST are robust in the presence of added respiratory motions. The dominant artifacts in the subtraction images are caused by the mismatches between the real object and the

  10. Boron and Coumaphos Residues in Hive Materials Following Treatments for the Control of Aethina tumida Murray.

    PubMed

    Valdovinos-Flores, Cesar; Gaspar-Ramírez, Octavio; Heras-Ramírez, María Elena; Lara-Álvarez, Carlos; Dorantes-Ugalde, José Antonio; Saldaña-Loza, Luz María

    2016-01-01

    In the search of alternatives for controlling Aethina tumida Murray, we recently proposed the BAA trap which uses boric acid and an attractant which mimics the process of fermentation caused by Kodamaea ohmeri in the hive. This yeast is excreted in the feces of A. tumida causing the fermentation of pollen and honey of infested hives and releasing compounds that function as aggregation pheromones to A. tumida. Since the boron is the toxic element in boric acid, the aim of this article is to assess the amount of boron residues in honey and beeswax from hives treated with the BAA trap. For this aim, the amount of bioaccumulated boron in products of untreated hives was first determined and then compared with the amount of boron of products from hives treated with the BAA trap in two distinct climatic and soil conditions. The study was conducted in the cities of Padilla, Tamaulipas, and Valladolid, Yucatan (Mexico) from August 2014 to March 2015. The quantity of boron in honey was significantly less in Yucatan than in Tamaulipas; this agrees with the boron deficiency among Luvisol and Leptosol soils found in Yucatan compared to the Vertisol soil found in Tamaulipas. In fact, the honey from Yucatan has lower boron levels than those reported in the literature. The BAA treatment was applied for four months, results show that the BAA trap does not have any residual effect in either honey or wax; i.e., there is no significant difference in boron content before and after treatment. On the other hand, the organophosphate pesticide coumaphos was found in 100% of wax samples and in 64% of honey samples collected from Yucatan. The concentration of coumaphos in honey ranges from 0.005 to 0.040 mg/kg, which are below Maximum Residue Limit (MRL) allowed in the European Union (0.1 mg/kg) but 7.14% of samples exceeded the MRL allowed in Canada (0.02 mg/kg).

  11. Boron and Coumaphos Residues in Hive Materials Following Treatments for the Control of Aethina tumida Murray

    PubMed Central

    Valdovinos-Flores, Cesar; Gaspar-Ramírez, Octavio; Heras–Ramírez, María Elena; Dorantes-Ugalde, José Antonio; Saldaña-Loza, Luz María

    2016-01-01

    In the search of alternatives for controlling Aethina tumida Murray, we recently proposed the BAA trap which uses boric acid and an attractant which mimics the process of fermentation caused by Kodamaea ohmeri in the hive. This yeast is excreted in the feces of A. tumida causing the fermentation of pollen and honey of infested hives and releasing compounds that function as aggregation pheromones to A. tumida. Since the boron is the toxic element in boric acid, the aim of this article is to assess the amount of boron residues in honey and beeswax from hives treated with the BAA trap. For this aim, the amount of bioaccumulated boron in products of untreated hives was first determined and then compared with the amount of boron of products from hives treated with the BAA trap in two distinct climatic and soil conditions. The study was conducted in the cities of Padilla, Tamaulipas, and Valladolid, Yucatan (Mexico) from August 2014 to March 2015. The quantity of boron in honey was significantly less in Yucatan than in Tamaulipas; this agrees with the boron deficiency among Luvisol and Leptosol soils found in Yucatan compared to the Vertisol soil found in Tamaulipas. In fact, the honey from Yucatan has lower boron levels than those reported in the literature. The BAA treatment was applied for four months, results show that the BAA trap does not have any residual effect in either honey or wax; i.e., there is no significant difference in boron content before and after treatment. On the other hand, the organophosphate pesticide coumaphos was found in 100% of wax samples and in 64% of honey samples collected from Yucatan. The concentration of coumaphos in honey ranges from 0.005 to 0.040 mg/kg, which are below Maximum Residue Limit (MRL) allowed in the European Union (0.1 mg/kg) but 7.14% of samples exceeded the MRL allowed in Canada (0.02 mg/kg). PMID:27092938

  12. Comparison of the presence of Shiga toxin 1 in food matrices as determined by an enzyme-linked immunosorbent assay and a biological activity assay.

    PubMed

    Lumor, Stephen E; Fredrickson, Neal R; Ronningen, Ian; Deen, Bronwyn D; Smith, Kenneth; Diez-Gonzalez, Francisco; Labuza, Theodore P

    2012-06-01

    This study was conducted to compare the identification of Shiga toxin 1 (Stx1) based on its specific biological activity and based on results of a commercial enzyme-linked immunosorbent assay (ELISA) kit. Stx1 was thermally treated for various periods in phosphate-buffered saline, milk, and orange juice. The residual Stx1 concentration was determined with the commercial ELISA kit, and its residual enzymatic activity (amount of adenine released from a 2,551-bp DNA substrate) was determined with a biological activity assay (BAA). Regression analysis indicated that the inactivation of Stx1 as a function of time followed first-order kinetics. The half-lives determined at 60, 65, 70, 75, 80, and 85°C were 9.96, 3.19, 2.67, 0.72, 0.47, and 0.29 min, respectively, using the BAA. The half-lives determined by the ELISA with thermal treatments at 70, 75, 80, and 85°C were 40.47, 11.03, 3.64, and 1.40 min, respectively. The Z, Q(10), and Arrhenius activation energy values derived by both assays were dissimilar, indicating that the rate of inactivation of the active site of Stx1 was less sensitive to temperature change than was denaturation of the epitope(s) used in the ELISA. These values were 10.28°C and 9.40 and 54.70 kcal/mol, respectively, with the ELISA and 16°C and 4.11 and 34 kcal/mol, respectively, with the BAA. Orange juice enhanced Stx1 inactivation as a function of increasing temperature, whereas inactivation in 2% milk was not very much different from that in phosphate-buffered saline. Our investigation indicates that the ELISA would be a reliable method for detecting the residual toxicity of heat-treated Stx1 because the half-lives determined with the ELISA were greater than those determined with the BAA (faster degradation) at all temperatures and were highly correlated (R(2) = 0.994) with those determined with the BAA.

  13. Multiplex detection of nine food-borne pathogens by mPCR and capillary electrophoresis after using a universal pre-enrichment medium.

    PubMed

    Villamizar-Rodríguez, Germán; Fernández, Javier; Marín, Laura; Muñiz, Juan; González, Isabel; Lombó, Felipe

    2015-01-01

    Routine microbiological quality analyses in food samples require, in some cases, an initial incubation in pre-enrichment medium. This is necessary in order to ensure that small amounts of pathogenic strains are going to be detected. In this work, a universal pre-enrichment medium has been developed for the simultaneous growth of Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Cronobacter sakazakii, Escherichia coli, Enterobacteriaceae family (38 species, 27 genera), Listeria monocytogenes, Staphylococcus aureus, Salmonella spp. (two species, 13 strains). Growth confirmation for all these species was achieved in all cases, with excellent enrichments. This was confirmed by plating on the corresponding selective agar media for each bacterium. This GVUM universal pre-enrichment medium could be useful in food microbiological analyses, where different pathogenic bacteria must be detected after a pre-enrichment step. Following, a mPCR reaction for detection of all these pathogens was developed, after designing a set of nine oligonucleotide pairs from specific genetic targets on gDNA from each of these bacteria, covering all available strains already sequenced in GenBank for each pathogen type. The detection limits have been 1 Genome Equivalent (GE), with the exception of the Fam. Enterobacteriaceae (5 GEs). We obtained amplification for all targets (from 70 to 251 bp, depending on the bacteria type), showing the capability of this method to detect the most important industrial and sanitary food-borne pathogens from a universal pre-enrichment medium. This method includes an initial pre-enrichment step (18 h), followed by a mPCR (2 h) and a capillary electrophoresis (30 min); avoiding the tedious and long lasting growing on solid media required in traditional analysis (1-4 days, depending on the specific pathogen and verification procedure). An external testing of this method was conducted in order to compare classical and mPCR methods. This evaluation was

  14. Multiplex detection of nine food-borne pathogens by mPCR and capillary electrophoresis after using a universal pre-enrichment medium

    PubMed Central

    Villamizar-Rodríguez, Germán; Fernández, Javier; Marín, Laura; Muñiz, Juan; González, Isabel; Lombó, Felipe

    2015-01-01

    Routine microbiological quality analyses in food samples require, in some cases, an initial incubation in pre-enrichment medium. This is necessary in order to ensure that small amounts of pathogenic strains are going to be detected. In this work, a universal pre-enrichment medium has been developed for the simultaneous growth of Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Cronobacter sakazakii, Escherichia coli, Enterobacteriaceae family (38 species, 27 genera), Listeria monocytogenes, Staphylococcus aureus, Salmonella spp. (two species, 13 strains). Growth confirmation for all these species was achieved in all cases, with excellent enrichments. This was confirmed by plating on the corresponding selective agar media for each bacterium. This GVUM universal pre-enrichment medium could be useful in food microbiological analyses, where different pathogenic bacteria must be detected after a pre-enrichment step. Following, a mPCR reaction for detection of all these pathogens was developed, after designing a set of nine oligonucleotide pairs from specific genetic targets on gDNA from each of these bacteria, covering all available strains already sequenced in GenBank for each pathogen type. The detection limits have been 1 Genome Equivalent (GE), with the exception of the Fam. Enterobacteriaceae (5 GEs). We obtained amplification for all targets (from 70 to 251 bp, depending on the bacteria type), showing the capability of this method to detect the most important industrial and sanitary food-borne pathogens from a universal pre-enrichment medium. This method includes an initial pre-enrichment step (18 h), followed by a mPCR (2 h) and a capillary electrophoresis (30 min); avoiding the tedious and long lasting growing on solid media required in traditional analysis (1–4 days, depending on the specific pathogen and verification procedure). An external testing of this method was conducted in order to compare classical and mPCR methods. This evaluation was

  15. In vitro antimicrobial effects of a novel Pentaherbs concoction for atopic dermatitis.

    PubMed

    Hon, Kam Lun; Ip, Margaret; Wong, Chun Kwok; Chan, Ben Chung Lap; Leung, Ping Chung; Leung, Ting Fan

    2018-05-01

    In a series of bench and clinical trials, our group has determined the immunologic effects and clinical efficacy of a concoction of five herbal ingredients (PentaHerbs Formula, PHF) in treating children with atopic eczema (AE). This study investigates the antimicrobial effects that may be induced with PHF treatment. We investigated the effects of PHF on the minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Staphylococcus aureus and various bacteria that are commonly present on the skin of patients with AE. Staphylococcus aureus ATCC 25923, Methicllin resistant Staphylococcus aureus (MRSA) ATCC BAA-43, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Enterobacter cloacae ATCC 13047, Proteus vulgaris ATCC 6380, and Acinetobacter baumannii ATCC 19606 were tested. PHF was more effective against Staphylococcus aureus ATCC 25923 and Methicllin resistant Staphylococcus aureus (MRSA) ATCC BAA-43. MIC and MBC were 1 and 25 mg/mL, respectively. PHF was more effective against Staphylococcus aureus ATCC 25923 and Methicllin resistant Staphylococcus aureus (MRSA) ATCC BAA-43t. PHF may be developed into a Staphylococcus aureus targeting topical application.

  16. Wavefront Tilt And Beam Walk Correction For A Pulsed Laser System

    NASA Astrophysics Data System (ADS)

    Bartosewcz, Mike; Tyburski, Joe

    1986-05-01

    The Lockheed Beam Alignment Assembly (BAA) is designed to be a space qualifiable, long life, low bandwidth beam stabilization system. The BAA will stabilize a wandering pulsed laser beam with an input beam tilt of ±750 microradians and translation of ±2.5 mm by two orders of magnitude at the bandwidth of interest. A bandwidth of three hertz was selected to remove laser and optical train thermal drifts and launch induced strain effects. The lambda over twenty RMS wavefront will be maintained in the optics at full power under vacuum test, to demonstrate space qualifiability and optical performance.

  17. 12 CFR Appendix B to Subpart A of... - Appendix B to Subpart A of Part 327

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Converted value Standard & Poor's: AAA 1.00 AA+ 1.05 AA 1.15 AA− 1.30 A+ 1.50 A 1.80 A− 2.20 BBB+ 2.70 BBB or worse 3.00 Moody's: Aaa 1.00 Aa1 1.05 Aa2 1.15 Aa3 1.30 A1 1.50 A2 1.80 A3 2.20 Baa1 2.70 Baa2 or worse 3.00 Fitch's: AAA 1.00 AA+ 1.05 AA 1.15 AA− 1.30 A+ 1.50 A 1.80 A− 2.20 BBB+ 2.70 BBB or worse 3...

  18. Demonstrations of Clarus system data : Clarus BAA projects.

    DOT National Transportation Integrated Search

    2005-08-01

    In 2002, FHWA awarded a field operational test to the Virginia Department of Transportation entitled (VDOT) Traffic Management Center (TMC) Applications of Archived Data Operational Test. The intent of the operational test was to use archived data to...

  19. Endothelial nitric oxide synthase polymorphisms and adaptation of parasympathetic modulation to exercise training.

    PubMed

    Silva, Bruno M; Neves, Fabricia J; Negrão, Marcelo V; Alves, Cleber R; Dias, Rodrigo G; Alves, Guilherme B; Pereira, Alexandre C; Rondon, Maria U; Krieger, José E; Negrão, Carlos E; DA Nóbrega, Antonio Claudio Lucas

    2011-09-01

    There is a large interindividual variation in the parasympathetic adaptation induced by aerobic exercise training, which may be partially attributed to genetic polymorphisms. Therefore, we investigated the association among three polymorphisms in the endothelial nitric oxide gene (-786T>C, 4b4a, and 894G>T), analyzed individually and as haplotypes, and the parasympathetic adaptation induced by exercise training. Eighty healthy males, age 20-35 yr, were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis, and haplotypes were inferred using the software PHASE 2.1. Autonomic modulation (i.e., HR variability and spontaneous baroreflex sensitivity) and peak oxygen consumption (VO(2peak)) were measured before and after training (running, moderate to severe intensity, three times per week, 60 min·day(-1), during 18 wk). Training increased VO(2peak) (P < 0.05) and decreased mean arterial pressure (P < 0.05) in the whole sample. Subjects with the -786C polymorphic allele had a significant reduction in baroreflex sensitivity after training (change: wild type (-786TT) = 2% ± 89% vs polymorphic (-786TC/CC) = -28% ± 60%, median ± quartile range, P = 0.03), and parasympathetic modulation was marginally reduced in subjects with the 894T polymorphic allele (change: wild type (894GG) = 8% ± 67% vs polymorphic (894GT/TT) = -18% ± 59%, median ± quartile range, P = 0.06). Furthermore, parasympathetic modulation percent change was different between the haplotypes containing wild-type alleles (-786T/4b/894G) and polymorphic alleles at positions -786 and 894 (-786C/4b/894T) (-6% ± 56% vs -41% ± 50%, median ± quartile range, P = 0.04). The polymorphic allele at position -786 and the haplotype containing polymorphic alleles at positions -786 and 894 in the endothelial nitric oxide gene were associated with decreased parasympathetic modulation after exercise training.

  20. Historical geographies of provincial science: themes in the setting and reception of the British Association for the Advancement of Science in Britain and Ireland, 1831-c.1939.

    PubMed

    Withers, Charles; Higgitt, Rebekah; Finnegan, Diarmid

    2008-09-01

    The British Association for the Advancement of Science sought to promote the understanding of science in various ways, principally by having annual meetings in different towns and cities throughout Britain and Ireland (and, from 1884, in Canada, South Africa and Australia). This paper considers how far the location of its meetings in different urban settings influenced the nature and reception of the association's activities in promoting science, from its foundation in 1831 to the later 1930s. Several themes concerning the production and reception of science--promoting, practising, writing and receiving--are examined in different urban contexts. We consider the ways in which towns were promoted as venues for and centres of science. We consider the role of local field sites, leading local practitioners and provincial institutions for science in attracting the association to different urban locations. The paper pays attention to excursions and to the evolution and content of the BAAS meeting handbook as a 'geographical' guide to the significance of the regional setting and to appropriate scientific venues. The paper considers the reception of BAAS meetings and explores how far the association's intentions for the promotion of science varied by location and by section within the BAAS. In examining these themes--the geographical setting of the association's meetings, the reception of association science in local civic and intellectual context and the importance of place to an understanding of what the BAAS did and how it was received--the paper extends existing knowledge of the association and contributes to recent work within the history of science which has emphasized the 'local' nature of science's making and reception and the mobility of scientific knowledge.

  1. [Possibility of fortifying milk nutrient mixtures for children with lactoglobulin against E. coli and Proteus].

    PubMed

    Zlatnik, E Iu

    1986-01-01

    Sweet milk nutrient mixtures, biologically active additives (BAA) and lactic acid ferments, intended for child nutrition, were enriched with the immune preparation lactoglobulin against E. coli and Proteus. Serological and immunochemical investigations of hemagglutinating activity and other characteristics of lactoglobulin in the enriched milk mixtures and BAA evidenced that the preparation retained its full value during the technological process and in the period of storage. No signs of lactoglobulin degradation during the production of a test batch of the milk mixture and BAA were detected, and a high hemagglutinating activity with respect to enteropathogenic E. coli and Proteus was recorded. This permitted the author to recommend the lactoglobulin-enriched sweet mixtures for prevention of acute intestinal infections and dysbacteriosis in young children. The in vitro study of the lactoglobulin interaction with pure cultures of lactobacillus and bifidobacteria showed its inertness to eubacteria. Four strains studied retained their growth and acid-forming properties after combined incubation with lactoglobulin and did not inhibit its activity. A conclusion has been made on the possibility of enrichment of lactic acid products, intended for child nutrition, with lactoglobulin against E. coli and Proteus.

  2. Structures and mechanical behaviors of Zr55Cu35Al10 bulk amorphous alloys at ambient and cryogenic temperatures

    NASA Astrophysics Data System (ADS)

    Fan, Cang; Liaw, P. K.; Haas, V.; Wall, J. J.; Choo, H.; Inoue, A.; Liu, C. T.

    2006-07-01

    Based on a systematic study of pair distribution functions, carried out at cryogenic and ambient temperatures, on as-cast and crystallized ternary Zr-based bulk amorphous alloys (BAAs), we found that the atoms in BAAs are inhomogenously distributed at a local atomic level. They exist as different clusters with significantly shorter bond lengths than their crystallized counterpart structures—intermetallic compounds, and these structures exist stably in the amorphous state. This results in additional free volume, which is about ˜7% larger than that measured by the Archimedes method. The compressive strength measured at ˜77K was found to be ˜16% larger than that measured at 298K . In this study, an amorphous structural model is proposed, in which strongly bonded clusters acting as units are randomly distributed and strongly correlated to one another, as the free volume forms between clusters. Simulations with reverse Monte Carlo were performed by combining icosehadral and cubic structures as the initial structures for the BAA. The simulations show results consistent with our model. An attempt has been made to connect the relationship between amorphous structures and their mechanical properties.

  3. Patient-specific finite element analysis of ascending aorta aneurysms

    PubMed Central

    Martin, Caitlin; Elefteriades, John

    2015-01-01

    Catastrophic ascending aorta aneurysm (AsAA) dissection and rupture can be prevented by elective surgical repair, but identifying individuals at risk remains a challenge. Typically the decision to operate is based primarily on the overall aneurysm size, which may not be a reliable indicator of risk. In this study, AsAA inflation and rupture was simulated in 27 patient-specific finite element models constructed from clinical CT imaging data and tissue mechanical testing data from matching patients. These patients included n = 8 with concomitant bicuspid aortic valve (BAV), n = 10 with bovine aortic arch (BAA), and n = 10 with neither BAV nor BAA. AsAA rupture risk was found to increase with elevated systolic wall stress and tissue stiffness. The aortic size index was sufficient for identifying the patients with the lowest risk of rupture, but unsuitable for delineating between patients at moderate and high risk. There was no correlation between BAV or BAA and AsAA rupture risk; however, the AsAA morphology was different among these patients. These results support the use of mechanical parameters such as vessel wall stress and tissue stiffness for AsAA presurgical evaluation. PMID:25770248

  4. 77 FR 14464 - Notice of Final Federal Agency Actions on Proposed Highway Project in Wisconsin

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-09

    ... a proposed highway project, Interstate I-94, I-894, and U.S. Highway 45 (Zoo Interchange) in... project: Interstate I-94, I-894, and U.S. Highway 45 (Zoo Interchange) in Milwaukee County, Wisconsin...

  5. Enterobacteriaceae in dehydrated powdered infant formula manufactured in Indonesia and Malaysia.

    PubMed

    Estuningsih, Sri; Kress, Claudia; Hassan, Abdulwahed A; Akineden, Omer; Schneider, Elisabeth; Usleber, Ewald

    2006-12-01

    To determine the occurrence of Salmonella and Shigella in infant formula from Southeast Asia, 74 packages of dehydrated powdered infant follow-on formula (recommended age, > 4 months) from five different manufacturers, four from Indonesia and one from Malaysia, were analyzed. None of the 25-g test portions yielded Salmonella or Shigella. However, further identification of colonies growing on selective media used for Salmonella and Shigella detection revealed the frequent occurrence of several other Enterobacteriaceae species. A total of 35 samples (47%) were positive for Enterobacteriaceae. Ten samples (13.5%) from two Indonesian manufacturers yielded Enterobacter sakazakii. Other Enterobacteriaceae isolated included Pantoea spp. (n = 12), Escherichia hermanii (n = 10), Enterobacter cloacae (n = 8), Klebsiella pneumoniae subsp. pneumoniae (n = 3), Citrobacter spp. (n = 2), Serratia spp. (n = 2), and Escherichia coli (n = 2). To our knowledge, this is the first report to describe the contamination of dehydrated powdered infant formula from Indonesia with E. sakazakii and several other Enterobacteriaceae that could be opportunistic pathogens. Improper preparation and conservation of these products could result in a health risk for infants in Indonesia.

  6. Piezochromism and structural and electronic properties of benz[a]anthracene under pressure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cai, Weizhao; Zhang, Rong; Yao, Yansun

    2017-01-31

    We report a combined experimental and theoretical study of the high pressure behavior of a herringbone-type hydrocarbon benz[a]anthracene (BaA) using fluorescence spectroscopy, X-ray diffraction, optical absorption, photoconductivity measurements, and first-principles density functional theory (DFT) calculations. The ambient-pressure molecular solid phase of BaA was found to be stable up to ~15.0 GPa. Increasing the external pressure within this region would induce a reversible piezochromic colour change in the sample, from yellow-green to light brown. The reversibility of the colour change was confirmed by both optical observations and fluorescence measurements. Further compression beyond 15 GPa leads to polymerization of the sample andmore » formation of an amorphous hydrogenated carbon. The low pressure crystalline phase is not recoverable when the sample is decompressed from pressure above 15 GPa. DFT investigation of the structures at zero temperature suggests that the formation of a crystalline polymeric phase can take place between 30 and 117 GPa, however the kinetic barriers hinder the process at low pressure regions. The phase transition is therefore suggested to proceed along a gradual transition path to an amorphous phase at a lower reaction threshold, activated by finite temperature effects. Optical absorption measurements reveal that the band gap of BaA decreases at high pressure, from 2.4 eV at 0.5 GPa to 1.0 eV at 50.6 GPa. The DFT calculations further suggest that the band gap of BaA in the molecular phase could reduce to ~0.1 eV at 117 GPa. Photoconductivity measurements show a continuous increase of photocurrent in the molecular phase region, which most likely originated from the increase of carrier mobility under pressure.« less

  7. Roseomonas elaeocarpi sp. nov., isolated from olive (Elaeocarpus hygrophilus Kurz.) phyllosphere.

    PubMed

    Damtab, Jenjira; Nutaratat, Pumin; Boontham, Wanatchaporn; Srisuk, Nantana; Duangmal, Kannika; Yurimoto, Hiroya; Sakai, Yasuyoshi; Muramatsu, Yuki; Nakagawa, Yasuyoshi

    2016-01-01

    An aerobic, Gram-stain-negative, coccobacillus-shaped, non-endospore-forming, pink-pigmented bacterium, designated PN2T, was isolated from an olive leaf. The strain grew at 15-35 °C with an optimum temperature for growth at 30 °C, and at pH 5.0-7.5 with an optimum pH for growth at 6.0. Growth was observed in the presence of up to 1.02 % (w/v) NaCl. The major fatty acids were C19 : 0 cyclo ω8c, C16 : 0 and C18 : 1ω7c. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, unknown aminolipids, an unknown phospholipid and an unknown lipid. The respiratory quinone was ubiquinone-10. The DNA G+C content of strain PN2T was 70.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain PN2T was closely related to members of the genus Roseomonas and shared highest similarity with Roseomonas mucosa ATCC BAA-692T (96.5 %), Roseomonas gilardii subsp. gilardii ATCC 49956T (96.2 %) and Roseomonas gilardii subsp. rosea ATCC BAA-691T (96.2 %). Furthermore, the DNA-DNA relatedness value between strain PN2T and the closest related species R. mucosa ATCC BAA-692T was 27 %. These data allowed the phenotypic and genotypic differentiation of strain PN2T from its closest phylogenetic neighbour (R. mucosa ATCC BAA-692T). Based on phenotypic and genotypic characteristics, strain PN2T is classified as representing a novel species of the genus Roseomonas for which the name Roseomonas elaeocarpi sp. nov. is proposed. The type strain is PN2T ( = BCC 44864T = NBRC 107871T).

  8. Preliminary Results Of PCA On MRO CRISM Multispectral Images

    NASA Astrophysics Data System (ADS)

    Klassen, David R.; Smith, M. D.

    2008-09-01

    Mars Reconnaissance Orbiter arrived at Mars in March 2006 and by September had achieved its science-phase orbit with the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) beginning its visible to near-infrared (VIS/NIR) spectral imaging shortly thereafter. One of the goals of CRISM is to fill in the spatial gaps between the various targeted observations, eventually mapping the entire surface. Due to the large volume of data this would create, the instrument works in a reduced spectral sampling mode creating "multispectral” images. From this data we can create image cubes using 70 wavelengths from 0.410 to 3.504 µm. We present here a preliminary analysis of these multispectral mode data products using the technique of Principal Components Analysis. Previous work with ground-based images has shown that over an entire visible hemisphere, there are only three to four meaningful components out of 32-105 wavelengths over 1.5-4.1 µm. The first two of these components are fairly consistent over all time intervals from day-to-day and season-to-season. [1-4] The preliminary work on the CRISM images cubes implies similar results_three to four significant principal components that are fairly consistent over time. We will show these components and a rough linear mixture modeling based on in-data spectral endmembers derived from the extrema of the principal components [5]. References: [1] Klassen, D. R. and Bell III, J. F. (2001) BAAS 33, 1069. [2] Klassen, D. R. and Bell III, J. F. (2003) BAAS, 35, 936. [3] Klassen, D. R., Wark, T. J., Cugliotta, C. G. (2005) BAAS, 37, 693. [4] Klassen, D. R. and Bell III, J. F. (2007) in preparation. [5] Klassen, D. R. and Bell III, J. F. (2000) BAAS, 32, 1105.

  9. [Biologically active food additives: their role in human body sanitation and in prophylaxis of alimentary-dependent diseases].

    PubMed

    Maev, E Z; Zaĭtseva, V P

    2002-09-01

    The different aspects of the problem of health maintaining and strengthening are discussed. The special attention is devoted to the problem of diet that at present is characterized by deficiency of macro- and micronutrients. It is supposed that this factor together with the change in ecological condition promotes the development of different somatic diseases and their atypical course. To correct the dietary regimen, to strengthen the body functional reserves and to improve its nonspecific resistance to the influence of environmental unfavorable and pathogenic factors the possibility of wide use of biologically active food additives (BAA) is discussed. The examples of BAAs based on plant materials and results of their use in health resort conditions are given.

  10. Draft Genome Sequence of the First Documented Clinical Siccibacter turicensis Isolate in Austria.

    PubMed

    Lepuschitz, Sarah; Pekard-Amenitsch, Shiva; Haunold, Renée; Schill, Simone; Schriebl, Agnes; Mach, Robert; Allerberger, Franz; Ruppitsch, Werner; Forsythe, Stephen J

    2018-05-03

    The nonpathogenic species Siccibacter turicensis is closely related to members of the food-associated pathogenic genus Cronobacter and has been detected in fruit powders, formula, spices, and herbs. Here, we report on the first clinical isolate of S. turicensis , recovered from the labial angle of a patient with angular cheilitis. Copyright © 2018 Lepuschitz et al.

  11. Dare County Gunnery Range, North Carolina. Limited Surface Observations Climatic Summary (LISOCS). Parts A-F.

    DTIC Science & Technology

    1988-01-01

    AIR wEATHER SERVICE/MAC--) STATION NUMBER: ?4695C STATIOK NAME: DARE COUNTY GUNNERY RANGE NC PERIOD OF PECORD: 7887 MONTH: JAN HOURSILSTi: ISO -1700...25D01 776 89.7 87.1 88.2 88.2 88.2 88.2 88.2 88.2 8.2 88.2 88:2 88.2 88.2 88.2 C GE 27001 78.8 85.9 88.2 89.4 89.4 89.9 89.4 89.4 90.6 97.6 93.6 90.6...78.6 81 .9 83. 4 83.4 85. 1 85 .7 86. 7 86.7 86.7 86.9 87.8 C)GE 27001 5 1.9 65.1 73.8 80.4 80.6 83 .9 85. 3 65.3 87.3 87.8 87.8 88.8 88.8 89.2 90. 1 G

  12. 78 FR 32690 - Certain Ammonium Nitrate From Ukraine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-894 (Review)] Certain Ammonium Nitrate... certain ammonium nitrate from Ukraine would be likely to lead to continuation or recurrence of material... Ammonium Nitrate from Ukraine: Investigation No. 731-TA-894 (Second Review). By order of the Commission...

  13. A multi-channel opto-electronic sensor to accurately monitor heart rate against motion artefact during exercise.

    PubMed

    Alzahrani, Abdullah; Hu, Sijung; Azorin-Peris, Vicente; Barrett, Laura; Esliger, Dale; Hayes, Matthew; Akbare, Shafique; Achart, Jérôme; Kuoch, Sylvain

    2015-10-12

    This study presents the use of a multi-channel opto-electronic sensor (OEPS) to effectively monitor critical physiological parameters whilst preventing motion artefact as increasingly demanded by personal healthcare. The aim of this work was to study how to capture the heart rate (HR) efficiently through a well-constructed OEPS and a 3-axis accelerometer with wireless communication. A protocol was designed to incorporate sitting, standing, walking, running and cycling. The datasets collected from these activities were processed to elaborate sport physiological effects. t-test, Bland-Altman Agreement (BAA), and correlation to evaluate the performance of the OEPS were used against Polar and Mio-Alpha HR monitors. No differences in the HR were found between OEPS, and either Polar or Mio-Alpha (both p > 0.05); a strong correlation was found between Polar and OEPS (r: 0.96, p < 0.001); the bias of BAA 0.85 bpm, the standard deviation (SD) 9.20 bpm, and the limits of agreement (LOA) from -17.18 bpm to +18.88 bpm. For the Mio-Alpha and OEPS, a strong correlation was found (r: 0.96, p < 0.001); the bias of BAA 1.63 bpm, SD 8.62 bpm, LOA from -15.27 bpm to +18.58 bpm. These results demonstrate the OEPS to be capable of carrying out real time and remote monitoring of heart rate.

  14. Halomonas neptunia sp. nov., Halomonas sulfidaeris sp. nov., Halomonas axialensis sp. nov. and Halomonas hydrothermalis sp. nov.: halophilic bacteria isolated from deep-sea hydrothermal-vent environments.

    PubMed

    Kaye, Jonathan Z; Márquez, M Carmen; Ventosa, Antonio; Baross, John A

    2004-03-01

    To assess the physiological and phylogenetic diversity of culturable halophilic bacteria in deep-sea hydrothermal-vent environments, six isolates obtained from low-temperature hydrothermal fluids, sulfide rock and hydrothermal plumes in North and South Pacific Ocean vent fields located at 1530-2580 m depth were fully characterized. Three strains were isolated on media that contained oligotrophic concentrations of organic carbon (0.002 % yeast extract). Sequencing of the 16S rRNA gene indicated that all strains belonged to the genus Halomonas in the gamma-subclass of the Proteobacteria. Consistent with previously described species, the novel strains were slightly to moderately halophilic and grew in media containing up to 22-27 % total salts. The isolates grew at temperatures as low as -1 to 2 degrees C and had temperature optima of 30 or 20-35 degrees C. Both the minimum and optimum temperatures for growth were similar to those of Antarctic and sea-ice Halomonas species and lower than typically observed for the genus as a whole. Phenotypic tests revealed that the isolates were physiologically versatile and tended to have more traits in common with each other than with closely related Halomonas species, presumably a reflection of their common deep-sea, hydrothermal-vent habitat of origin. The G+C content of the DNA for all strains was 56.0-57.6 mol%, and DNA-DNA hybridization experiments revealed that four strains (Eplume1(T), Esulfide1(T), Althf1(T) and Slthf2(T)) represented novel species and that two strains (Eplume2 and Slthf1) were related to Halomonas meridiana. The proposed new species names are Halomonas neptunia (type strain Eplume1(T)=ATCC BAA-805(T)=CECT 5815(T)=DSM 15720(T)), Halomonas sulfidaeris (type strain Esulfide1(T)=ATCC BAA-803(T)=CECT 5817(T)=DSM 15722(T)), Halomonas axialensis (type strain Althf1(T)=ATCC BAA-802(T)=CECT 5812(T)=DSM 15723(T)) and Halomonas hydrothermalis (type strain Slthf2(T)=ATCC BAA-800(T)=CECT 5814(T)=DSM 15725(T)).

  15. Mammalian Cell Cytotoxicity and Genotoxicity of the Haloacetic Acids, A Major Class of Drinking Water Disinfection By-Products

    EPA Science Inventory

    The haloacetic acids (HAAs) are disinfection by-products (DBPs) that are formed during the disinfection of drinking water, wastewaters and recreational pool waters. Currently, five HAAs [bromoacetic acid (BAA), dibromoacetic acid (DBAA), chloroacetic acid (CAA), dichloroacetic ac...

  16. A CAD system and quality assurance protocol for bone age assessment utilizing digital hand atlas

    NASA Astrophysics Data System (ADS)

    Gertych, Arakadiusz; Zhang, Aifeng; Ferrara, Benjamin; Liu, Brent J.

    2007-03-01

    Determination of bone age assessment (BAA) in pediatric radiology is a task based on detailed analysis of patient's left hand X-ray. The current standard utilized in clinical practice relies on a subjective comparison of the hand with patterns in the book atlas. The computerized approach to BAA (CBAA) utilizes automatic analysis of the regions of interest in the hand image. This procedure is followed by extraction of quantitative features sensitive to skeletal development that are further converted to a bone age value utilizing knowledge from the digital hand atlas (DHA). This also allows providing BAA results resembling current clinical approach. All developed methodologies have been combined into one CAD module with a graphical user interface (GUI). CBAA can also improve the statistical and analytical accuracy based on a clinical work-flow analysis. For this purpose a quality assurance protocol (QAP) has been developed. Implementation of the QAP helped to make the CAD more robust and find images that cannot meet conditions required by DHA standards. Moreover, the entire CAD-DHA system may gain further benefits if clinical acquisition protocol is modified. The goal of this study is to present the performance improvement of the overall CAD-DHA system with QAP and the comparison of the CAD results with chronological age of 1390 normal subjects from the DHA. The CAD workstation can process images from local image database or from a PACS server.

  17. Demonstration of ECDA Applicability and Reliability for Demanding Situations

    DOT National Transportation Integrated Search

    2008-08-31

    On June 2, 2005, PHMSA issued the fifth Broad Agency Announcement, #DTPH56-05-BAA-0001, which included research to improve the understanding of Direct Assessment (DA) methods and practices in challenging situations. This project received support from...

  18. Supernova Cosmology Project

    Science.gov Websites

    segment of this Poster from the January 1998 Meeting of the American Astronomical Society (i.e. the Meeting of the American Astronomical Society, Washington, DC. (referenced in Perlmutter et al., B.A.A.S

  19. The BAA observatories and the origins of the instrument collection

    NASA Astrophysics Data System (ADS)

    Marriott, R. A.

    2007-12-01

    Within a few months of the founding of the Association in 1890 October, the membership numbered several hundred amateur and professional astronomers in Britain and around the world. International recognition was also marked by a number of eminent speakers at meetings, including the instrument maker John A. Brashear, of Allegheny, Pennsylvania. In 1888 Brashear had toured the British Isles and Europe, visiting observatories and meeting many eminent astronomers. He seems to have been impressed with everyone he met - particularly British amateurs - and during his second visit to England in 1892 he spoke at the Association's meeting on April 27. In 1890 December he presented to the Association a speculum-metal diffraction grating which had been prepared at his own works and ruled on Henry Rowland's engine at Johns Hopkins University, Baltimore.

  20. A Different Kind of Web-Based Knowledge Management: The DTRA Acquisition ToolBook

    DTIC Science & Technology

    2008-12-01

    Reimbursement Order MIPR: Military Interdepartmental Purchase Request PWS: Performance Work Statement SOO: Statement of Objectives SOW: Scope of Work Figure 1...Competitive BAA: Broad Agency Announcement IACRO: Inter-Agency Cost Reimbur ement Order MIPR: Military Interdepartmental Purchas Request PWS

  1. Phylogenetic Analysis and Antimicrobial Profiles of Cultured Emerging Opportunistic Pathogens (Phyla Actinobacteria and Proteobacteria) Identified in Hot Springs

    PubMed Central

    Jardine, Jocelyn Leonie; Mavumengwana, Vuyo

    2017-01-01

    Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria, Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment. PMID:28914802

  2. Phylogenetic Analysis and Antimicrobial Profiles of Cultured Emerging Opportunistic Pathogens (Phyla Actinobacteria and Proteobacteria) Identified in Hot Springs.

    PubMed

    Jardine, Jocelyn Leonie; Abia, Akebe Luther King; Mavumengwana, Vuyo; Ubomba-Jaswa, Eunice

    2017-09-15

    Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria , Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment.

  3. United States Counter-narcotics Policies towards Burma, and How the Illegal Myanmar Regime is Manipulating Those Policies to Commit Ethnic Genocide

    DTIC Science & Technology

    2006-06-01

    minority, insurgent, Southeast Asia, ASEAN, UN, United Nations, United Nations Security Council, Shan, Karen, Wa, yaa baa, methamphetamine , illicit... Methamphetamines ............................................................................63 B. ILLICT NARCOTIC TRANSPORTATION...129 x THIS PAGE INTENTIONALLY LEFT BLANK xi LIST OF FIGURES Figure 1. British Conquests

  4. 10 CFR Appendix A to Part 30 - Criteria Relating to Use of Financial Tests and Parent Company Guarantees for Providing...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... company must have: (i) A current rating for its most recent bond issuance of AAA, AA, A, or BBB as issued by Standard and Poor's or Aaa, Aa, A, or Baa as issued by Moody's; and (ii) Tangible net worth each...

  5. Biotransformation in the zebrafish embryo -temporal gene transcription changes of cytochrome P450 enzymes and internal exposure dynamics of the AhR binding xenobiotic benz[a]anthracene.

    PubMed

    Kühnert, Agnes; Vogs, Carolina; Seiwert, Bettina; Aulhorn, Silke; Altenburger, Rolf; Hollert, Henner; Küster, Eberhard; Busch, Wibke

    2017-11-01

    Not much is known about the biotransformation capability of zebrafish (Danio rerio) embryos. For understanding possible toxicity differences to adult fish, it might be crucial to understand the biotransformation of chemicals in zebrafish embryos i.e. as part of toxicokinetics. The biotransformation capabilities were analysed for two different stages of zebrafish embryos in conjunction with the internal concentrations of a xenobiotic. Zebrafish embryos of the late cleavage/early blastula period (2-26 hpf) and the early pharyngula period (26-50 hpf) were exposed for 24 h to the AhR binding compound benz[a]anthracene (BaA). Time dependent changes in cyp transcription (cyp1a, cyp1b1, cyp1c1 and cyp1c2) as well as concentration & time-dependent courses of BaA in the fish embryo and the exposure medium were analysed. Additionally, the CYP mediated formation of biotransformation products was investigated. We found correlations between transcriptional responses and the internal concentration for both exposure types. These correlations were depending on the start of the exposure i.e. the age of the exposed embryo. While no significant induction of the examined gene transcripts was observed in the first 12 h of exposure beginning in the blastula period a correlation was apparent when exposure started later i.e. in the pharyngula period. A significant induction of cyp1a was detected already after 1.5 h of BaA exposure. Gene transcripts for cyp1b1, cyp1c1 and cyp1c2 showed expressions distinctly different from cyp1a and were, in general, less inducible by BaA in both exposure windows. The toxicokinetic analysis showed that the biotransformation capability was fivefold higher in the older fish embryos. Biotransformation products of phase I reactions were found between 32 hpf and 50 hpf and were tentatively identified as benz[a]anthracene-phenol and benz[a]anthracene-dihydrodiol-epoxide. In conclusion, not only duration but also onset of exposure in relation to the

  6. Endothelial nitric oxide synthase polymorphism and prognosis in systolic heart failure patients.

    PubMed

    Azzam, Naiel; Zafrir, Barak; Fares, Fuad; Smith, Yoav; Salman, Nabeeh; Nevzorov, Roman; Amir, Offer

    2015-05-01

    The endothelial nitric oxide synthase (eNOS) gene single nucleotide polymorphism G894T is associated with thrombotic vascular diseases. However, its functional significance is controversial and data are scarce concerning its influence in heart failure (HF). We studied 215 patients with chronic systolic HF. DNA was analyzed for eNOS gene G894T polymorphism using PCR and DNA sequencing. Evaluation of clinical characteristics and analysis of factors associated with 2-year mortality were performed for the homozygous G-allele G894T variant (GG), relative to the TT and GT variants. The genotype distributions of eNOS G894T alleles were: GG 135 patients (63%) and TT/GT 80 (37%). Two-year mortality was significantly higher in the GG variant (48%) than the combined TT/GT group (32%). The usage of nitrates was associated with increased 2-year mortality (HR 2.0, 95% CI 1.28-3.17; p = 0.003), which was most significant in the GG group treated with nitrates (73.5%) in comparison to the TT/GT group not treated with nitrates (34%); HR 2.75, 95% CI 1.57-4.79, P < 0.001. Homozygosity for the G allele of the eNOS G894T polymorphism was associated with worse survival in systolic HF patients, especially in those treated with nitrates. ENOS polymorphism may result in different mechanistic interactions in HF than in thrombotic vascular diseases, suggesting that overexpression of NO may be associated with deleterious effects in systolic HF. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. 77 FR 56638 - Combined Notice of Filings #1

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-13

    ...: 5 p.m. e.t. 9/26/12. Docket Numbers: ER12-2586-000. Applicants: PacifiCorp. Description: BPA Agmt for Pilot Butte Sub Mtring and Trnsfr CEC to BPA BAA to be effective 11/6/2012. Filed Date: 9/6/12...

  8. Research and development of ultrasonic tomography technology for three-dimensional imaging of internal rail flaws : modeling and simulation.

    DOT National Transportation Integrated Search

    2013-04-01

    This report covers the work performed under the FRA High-Speed BAA 20102011 program to demonstrate the technology of ultrasonic tomography for 3-D imaging of internal rail flaws. There is a need to develop new technologies that are able to quantif...

  9. Mathematics, Information, and Life Sciences

    DTIC Science & Technology

    2012-03-05

    INS • Chip -scale atomic clocks • Ad hoc networks • Polymorphic networks • Agile networks • Laser communications • Frequency-agile RF systems...FY12 BAA Bionavigation (Bio) Neuromorphic Computing (Human) Multi-scale Modeling (Math) Foundations of Information Systems (Info) BRI

  10. Nathaniel Everett Green: artist and astronomer

    NASA Astrophysics Data System (ADS)

    McKim, R. J.

    2004-02-01

    N. E. Green, a well-known BAA member from the decade of the 1890s, managed to successfully combine his hobby with his profession as a landscape artist and art teacher. One-time drawing master to Queen Victoria, and exhibitor at the Royal Academy, Green became equally famous for his beautiful and realistic drawings of the planets, above all for his expedition to Madeira in 1877 to observe the perihelic opposition of Mars. He inevitably became an important figure in the early martian 'canal debate'. Green was an Original Member of the BAA who twice directed the early Saturn Section, and ultimately served as President in 1896-'98. In this paper Green's life and works are reviewed, together with new details of his instruments and his approach to painting and drawing. Opportunity has been taken to publish some more of his original work, in colour, for the very first time.

  11. Effects of Moral Conduct Waivers on First-Term Attrition of U.S. Army Soldiers

    DTIC Science & Technology

    2008-03-01

    Stephen L. Mehay Co-Advisor Robert N. Beck Dean, Graduate School of Business and Public Policy iv THIS PAGE INTENTIONALLY LEFT BLANK v...GUARD RECRUITING CENTER. Other Waiver BAA DEPENDENCY OF A MILITARY SPOUSE WAIVER GRANTED BY THE HIGHEST AUTHORITY LEVEL. Other Waiver BAB

  12. 48 CFR 35.016 - Broad agency announcement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Broad agency announcement... CATEGORIES OF CONTRACTING RESEARCH AND DEVELOPMENT CONTRACTING 35.016 Broad agency announcement. (a) General. This paragraph prescribes procedures for the use of the broad agency announcement (BAA) with Peer or...

  13. 48 CFR 35.016 - Broad agency announcement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Broad agency announcement... CATEGORIES OF CONTRACTING RESEARCH AND DEVELOPMENT CONTRACTING 35.016 Broad agency announcement. (a) General. This paragraph prescribes procedures for the use of the broad agency announcement (BAA) with Peer or...

  14. 48 CFR 35.016 - Broad agency announcement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Broad agency announcement... CATEGORIES OF CONTRACTING RESEARCH AND DEVELOPMENT CONTRACTING 35.016 Broad agency announcement. (a) General. This paragraph prescribes procedures for the use of the broad agency announcement (BAA) with Peer or...

  15. 48 CFR 35.016 - Broad agency announcement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Broad agency announcement... CATEGORIES OF CONTRACTING RESEARCH AND DEVELOPMENT CONTRACTING 35.016 Broad agency announcement. (a) General. This paragraph prescribes procedures for the use of the broad agency announcement (BAA) with Peer or...

  16. Precision Antenna Measurement System (PAMS) Engineering Services

    DTIC Science & Technology

    1978-04-01

    8217) = receiving antenna gain for vertical polarization. The total direct signal power is Following Beck /narn and Spizzachino , the specular component...method may be valid for the problem. Very often, however, the physical optics 92 approach baaed on a solution of the wave equation will have to

  17. An Efficient Buchwald-Hartwig/Reductive Cyclization for the Scaffold Diversification of Halogenated Phenazines: Potent Antibacterial Targeting, Biofilm Eradication, and Prodrug Exploration.

    PubMed

    Garrison, Aaron T; Abouelhassan, Yasmeen; Kallifidas, Dimitris; Tan, Hao; Kim, Young S; Jin, Shouguang; Luesch, Hendrik; Huigens, Robert W

    2018-05-10

    Bacterial biofilms are surface-attached communities comprised of nonreplicating persister cells housed within a protective extracellular matrix. Biofilms display tolerance toward conventional antibiotics, occur in ∼80% of infections, and lead to >500000 deaths annually. We recently identified halogenated phenazine (HP) analogues which demonstrate biofilm-eradicating activities against priority pathogens; however, the synthesis of phenazines presents limitations. Herein, we report a refined HP synthesis which expedited the identification of improved biofilm-eradicating agents. 1-Methoxyphenazine scaffolds were generated through a Buchwald-Hartwig cross-coupling (70% average yield) and subsequent reductive cyclization (68% average yield), expediting the discovery of potent biofilm-eradicating HPs (e.g., 61: MRSA BAA-1707 MBEC = 4.69 μM). We also developed bacterial-selective prodrugs (reductively activated quinone-alkyloxycarbonyloxymethyl moiety) to afford HP 87, which demonstrated excellent antibacterial and biofilm eradication activities against MRSA BAA-1707 (MIC = 0.15 μM, MBEC = 12.5 μM). Furthermore, active HPs herein exhibit negligible cytotoxic or hemolytic effects, highlighting their potential to target biofilms.

  18. Monohaloacetic acid drinking water disinfection by-products inhibit follicle growth and steroidogenesis in mouse ovarian antral follicles in vitro.

    PubMed

    Jeong, Clara H; Gao, Liying; Dettro, Tyler; Wagner, Elizabeth D; Ricke, William A; Plewa, Michael J; Flaws, Jodi A

    2016-07-01

    Water disinfection greatly reduced the incidence of waterborne diseases, but the reaction between disinfectants and natural organic matter in water leads to the formation of drinking water disinfection by-products (DBPs). DBPs have been shown to be toxic, but their effects on the ovary are not well defined. This study tested the hypothesis that monohalogenated DBPs (chloroacetic acid, CAA; bromoacetic acid, BAA; iodoacetic acid, IAA) inhibit antral follicle growth and steroidogenesis in mouse ovarian follicles. Antral follicles were isolated and cultured with either vehicle or DBPs (0.25-1.00mM of CAA; 2-15μM of BAA or IAA) for 48 and 96h. Follicle growth was measured every 24h and the media were analyzed for estradiol levels at 96h. Exposure to DBPs significantly inhibited antral follicle growth and reduced estradiol levels compared to controls. These data demonstrate that DBP exposure caused ovarian toxicity in vitro. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Monohaloacetic acid drinking water disinfection by-products inhibit follicle growth and steroidogenesis in mouse ovarian antral follicles in vitro

    PubMed Central

    Jeong, Clara H.; Gao, Liying; Dettro, Tyler; Wagner, Elizabeth D.; Ricke, William A.; Plewa, Michael J.; Flaws, Jodi A.

    2016-01-01

    Water disinfection greatly reduced the incidence of waterborne diseases, but the reaction between disinfectants and natural organic matter in water leads to the formation of drinking water disinfection by-products (DBPs). DBPs have been shown to be toxic, but their effects on the ovary are not well defined. This study tested the hypothesis that monohalogenated DBPs (chloroacetic acid, CAA; bromoacetic acid, BAA; iodoacetic acid, IAA) inhibit antral follicle growth and steroidogenesis in mouse ovarian follicles. Antral follicles were isolated and cultured with either vehicle or DBPs (0.25–1.00 mM of CAA; 2–15 µM of BAA or IAA) for 48 and 96 h. Follicle growth was measured every 24 h and the media were analyzed for estradiol levels at 96 h. Exposure to DBPs significantly inhibited antral follicle growth and reduced estradiol levels compared to controls. These data demonstrate that DBP exposure caused ovarian toxicity in vitro. PMID:27151372

  20. Shallow-Water Reverberation

    DTIC Science & Technology

    2000-09-30

    Shallow- Water Reverberation J. X. Zhou School of Mechanical Engineering Georgia Institute of Technology Atlanta, Georgia 30332-0405 phone: (404) 894...6793 fax: (404) 894-7790 e-mail: jixun.zhou@me.gatech.edu Award Number: N00014-97-1-0170 Thrust Category: Shallow- Water Acoustics LONG-TERM GOALS...The long-term goals of this work are: to develop a theoretical model for predicting the reverberation in shallow water , to derive both small-angle

  1. Maxima and O-C Diagrams for 489 Mira Stars

    NASA Astrophysics Data System (ADS)

    Karlsson, T.

    2013-11-01

    Maxima for 489 Mira stars have been compiled. They were computed with data from AAVSO, AFOEV, VSOLJ, and BAA-VSS and collected from published maxima. The result is presented in a mysql database and on web pages with O-C diagrams, periods and some statistical information for each star.

  2. Proceedings of Damping 89, Volume 2, West Palm Beach, FL, 8-10 February 1989

    DTIC Science & Technology

    1989-11-01

    Vinyl Methyl Ether)-Polystyrene Blends and IPN’s J. J. Fay, Dr. C. J. Murphy, Dr. D. A. Thomas and Prof. L. H. Sperling BAA Time-Temperature...Structural Vibrations with Piezoelectric Materials and Passive Electrical Networks N. W. Hagood and Prof. A. von Flotow ICC Passive Electromagnetic

  3. Teachers Talking Together: The Power of Professional Community

    ERIC Educational Resources Information Center

    Nathan, Linda

    2008-01-01

    Schools that encourage teachers to do excellent work, as Boston Arts Academy (BAA) does, are "professional learning communities." A professional learning community exists when the entire faculty and staff, including the administration, work together towards a shared set of standards and assessments that are known to everyone, including…

  4. Human cell toxicogenomic analysis of bromoacetic acid: a regulated drinking water disinfection by-product.

    PubMed

    Muellner, Mark G; Attene-Ramos, Matias S; Hudson, Matthew E; Wagner, Elizabeth D; Plewa, Michael J

    2010-04-01

    The disinfection of drinking water is a major achievement in protecting the public health. However, current disinfection methods also generate disinfection by-products (DBPs). Many DBPs are cytotoxic, genotoxic, teratogenic, and carcinogenic and represent an important class of environmentally hazardous chemicals that may carry long-term human health implications. The objective of this research was to integrate in vitro toxicology with focused toxicogenomic analysis of the regulated DBP, bromoacetic acid (BAA) and to evaluate modulation of gene expression involved in DNA damage/repair and toxic responses, with nontransformed human cells. We generated transcriptome profiles for 168 genes with 30 min and 4 hr exposure times that did not induce acute cytotoxicity. Using qRT-PCR gene arrays, the levels of 25 transcripts were modulated to a statistically significant degree in response to a 30 min treatment with BAA (16 transcripts upregulated and nine downregulated). The largest changes were observed for RAD9A and BRCA1. The majority of the altered transcript profiles are genes involved in DNA repair, especially the repair of double strand DNA breaks, and in cell cycle regulation. With 4 hr of treatment the expression of 28 genes was modulated (12 upregulated and 16 downregulated); the largest fold changes were in HMOX1 and FMO1. This work represents the first nontransformed human cell toxicogenomic study with a regulated drinking water disinfection by-product. These data implicate double strand DNA breaks as a feature of BAA exposure. Future toxicogenomic studies of DBPs will further strengthen our limited knowledge in this growing area of drinking water research. Copyright 2009 Wiley-Liss, Inc.

  5. Relationship of the MTHFD1 (rs2236225), eNOS (rs1799983), CBS (rs2850144) and ACE (rs4343) gene polymorphisms in a population of Iranian pediatric patients with congenital heart defects.

    PubMed

    Khatami, Mehri; Ratki, Farzaneh Morteza; Tajfar, Saba; Akrami, Fatemeh

    2017-09-01

    Congenital heart defects are structural cardiovascular malformations that arise from abnormal formation of the heart or major blood vessels during the fetal period. To investigate the association of 4 single nucleotide polymorphisms (SNPs) in the MTHFD1, eNOS, CBS and ACE genes, we evaluated their relationship with CHD in Iranian patients. In this case-control study, a total of 102 children with CHD and 98 control children were enrolled. Four SNPs including MTHFD1 G1958A, eNOS G894T, CBS C-4673G and ACE A2350G were genotyped by PCR-SSCP, Multiplex ARMS PCR and PCR-RFLP methods and confirmed by direct sequencing. We genotyped 102 patients and 98 controls for four polymorphisms by statistically analysis. There were three SNPs including MTHFD1 G1958A, eNOS G894T and ACE A2350G which might increase the risk of CHD, but CBS C-4673G was not significantly different between patients and controls. (P = 0.017, P = 0.048, P = 0.025 and P = 0.081 respectively). The allele frequencies of three SNPs for MTHFD1 G1958A, eNOS G894T and ACE A2350G in CHD are higher than that in control. Our results show that there is a significant relationship between MTHFD1 G1958A, eNOS G894T and ACE A2350G polymorphisms with CHD. Therefore, The AA and GA genotypes of MTHFD1 G1958A, TT and GT genotypes of eNOS G894T and the AA and GA genotypes of ACE A2350G are susceptible factors for CHD and may increase the risk of CHD. Copyright © 2017. Published by Elsevier Taiwan.

  6. Growth promoting technologies reduce greenhouse gas, alcohol, and ammonia emissions from feedlot cattle.

    PubMed

    Stackhouse-Lawson, K R; Calvo, M S; Place, S E; Armitage, T L; Pan, Y; Zhao, Y; Mitloehner, F M

    2013-11-01

    Increased animal productivity has the potential to reduce the environmental impact per unit of consumable product and is believed to be the most promising and sustainable mitigation technique to meet increasing demand for high quality protein. The feedlot industry uses ionophores, antibiotics, growth implants, and β2-adrenergic agonists to improve health and growth performance of cattle. These technologies not only increase productivity but also alter microbes in the rumen and increase nitrogen retention in the animal, which may lead to changes in greenhouse gas (GHG), volatile organic compound (VOC), and ammonia (NH3) emissions from feedlot cattle. The present study investigated GHG, VOC, and NH3 emissions from 160 Angus crossbred steers. Steers were blocked by weight in a randomized block design and assigned to 16 pens of 10 animals each. Treatments applied were 1) control (CON; no technology application), 2) monensin and tylosin phosphate (MON), 3) monensin, tylosin phosphate, and growth implant (IMP), and 4) monensin, tylosin phosphate, growth implant, and zilpaterol hydrochloride (fed during the last 20 d of the feeding period; BAA). Cattle were on feed for an average of 107 d. Performance variables (DMI, BW, ADG, and G:F) and carcass traits (HCW, dressing percent, KPH, LM area, fat thickness, marbling score, yield grade, and quality grade) were measured. Gaseous emissions were measured during the last 10 d of the feeding period when animals were housed in 4 totally enclosed identical cattle pen enclosures. To quantify gaseous emissions a 4×4 Latin square design (n=4) was used. Gaseous emissions were analyzed using Proc Mixed in SAS and reported in grams per kilogram HCW per day and grams per kilogram per animal per hour. Treatment with IMP and BAA increased (P<0.05) ADG, final BW, and HCW. Cattle on BAA had greater HCW and LM area (P<0.05) and had lower (P<0.05) CH4, methanol, and NH3 emissions per kilogram HCW than cattle on the remaining treatments

  7. --No Title--

    Science.gov Websites

    (Perlmutter et al., B.A.A.S., v. 29, no. 5, p. 1351, 1997) Click on this reduced-size poster to see enlarged sections of the poster. Note: to see the captions in the enlarged sections scroll to the bottom of the enlarged page.

  8. Effects feeding zilpaterol hydrochloride on growth performance, fillet yeild, and body composition of rainbow trout, nile, tilapia, and channel catfish

    USDA-ARS?s Scientific Manuscript database

    Zilpaterol hydrochloride (ZH) is a potent ß-adrenergic agonist (BAA) that has been used in feedlot cattle to increase average daily gain, feed efficiency, yield of trimmed cuts, and dress out percent. While positive effects of ZH have been observed in cattle, there have been no reports of this prod...

  9. Survey on Classifying Human Actions Through Visual Sensors

    DTIC Science & Technology

    2011-05-04

    47] Herrera, A., Beck , A., Bell, D., Miller, P., Wu, Q., Yan, W., “Behaviour Analysis and Prediction in Image Sequences Using Rough Sets...report TR-97-021, University of Berkeley, 1998 [83] DARPA Mind’s Eye Broad Agency Announcement, DARPA- BAA -10-53, 2010 www.darpa.mil/tcto/docs

  10. TNFalpha -308 C-->t and -863 C-->a polymorphisms and spermiogram characteristics.

    PubMed

    Kurz, Christine; Bentz, Eva-Katrin; Denschlag, Dominik; Berner, Isabel; Keck, Christoph; Tempfer, Clemens B; Pietrowski, Detlef

    2008-01-01

    Genetic factors may play a role in male infertility. In a prospective case-control study, we assessed the allele and genotype frequencies of the TNFalpha -308 C-->T and -863 C-->A polymorphisms, detected by PCR of sperm DNA, of 577 Caucasian men recruited in an infertility clinic. Semen sampling was performed and spermiogram results were correlated to genetic data. The allele frequencies of the TNFalpha -308 C-->T and -863 C-->A polymorphisms were not significantly different between non-normozoospermic (n = 447) and normozoospermic (n = 130) men [758/894 (85%) and 134/894 (15%) vs. 213/269 (82%) and 43/260 (18%), p = 0.5, odds ratio (OR) 1.1, 95% confidence interval (CI) 0.74-1.76, and 749/894 (84%) and 145/894 (16%) vs. 212/260 (82%) and 48/260 (18%), p = 0.4, OR 1.2, 95% CI 0.78-1.76, respectively]. The genotype frequencies of the TNFalpha -308 C-->T and -863 C-->A polymorphisms were also not significantly different between non-normozoospermic and normozoospermic men. In addition, mutant alleles were not overrepresented in subgroups of men with the oligoasthenoteratozoospermia syndrome and asthenozoospermia. The TNFalpha -308 C-->T and -863 C-->A polymorphisms are not associated with spermiogram characteristics and do not represent molecular markers for genetic susceptibility to male infertility. Copyright 2008 S. Karger AG, Basel.

  11. Somali Syntax,

    DTIC Science & Technology

    1979-01-01

    they - go The Vietnamese people should be allowed the right of determining their own destiny . 174" a.- ] !- ’--- _ (373) Anaa warrameya. I/SP (baa... embryo of a form of prepositional government which is the same for verbs and nouns alike and which is developing on the basis of a spatial noun

  12. 18F-Flortaucipir Binding in Choroid Plexus: Related to Race and Hippocampus Signal.

    PubMed

    Lee, Christopher M; Jacobs, Heidi I L; Marquié, Marta; Becker, John A; Andrea, Nicolas V; Jin, David S; Schultz, Aaron P; Frosch, Matthew P; Gómez-Isla, Teresa; Sperling, Reisa A; Johnson, Keith A

    2018-01-01

    On target 18F-Flortaucipir (FTP) binding of Alzheimer's disease tau aggregates and off-target binding of melanocytes have been demonstrated with autoradiography. We aimed to investigate the hypothesis that if binding in choroid plexus (CP) is due to melanocytes, the signal would be elevated in Black/African American (B/AA) compared to White (W) participants. In addition, we examined whether CP signal affects measurements in adjacent regions, and whether correcting for spill-in effects has an influence on associations between hippocampus (HC) FTP and amyloid or cognition. FTP race differences in 147 Harvard Aging Brain Study participants (23 B/AA, 124W) were examined in CP, HC, HC covaried for CP, amygdala, inferior temporal gyrus, entorhinal cortex, and fusiform regions. Associations between CP FTP and other regions-of-interest (ROIs) were probed to assess spill-in effects. A statistical regression approach to attenuate CP spill-in was tested by relating adjusted HC SUVR residuals and unadjusted HC SUVR to race, cognition and amyloid. All analyses were covaried for age, sex, education and amyloid deposition, and Bonferroni-corrected for multiple comparisons. B/AA individuals had elevated CP and HC SUVR (p < 0.007), whereas other ROI SUVR and HC SUVR covaried for CP SUVR did not show race differences (p > 0.05). CP SUVR was associated with HC SUVR (p < 10-14), but with no other ROI SUVR (p > 0.05). When adjusting HC SUVR for CP SUVR, no race differences in residual HC SUVR were detected, and relationships with amyloid and memory became apparent. Melanocyte FTP binding may account partially for high CP signal. This off-target binding affects mainly HC FTP measurements, which should be interpreted with caution.

  13. 18F-Flortaucipir Binding in Choroid Plexus: Related to Race and Hippocampus Signal

    PubMed Central

    Lee, Christopher M.; Jacobs, Heidi I.L.; Marquié, Marta; Becker, John A.; Andrea, Nicolas V.; Jin, David S.; Schultz, Aaron P.; Frosch, Matthew P.; Gómez-Isla, Teresa; Sperling, Reisa A.; Johnson, Keith A.

    2018-01-01

    Background On target 18F-Flortaucipir (FTP) binding of Alzheimer’s disease tau aggregates and off-target binding of melanocytes have been demonstrated with autoradiography. Objective We aimed to investigate the hypothesis that if binding in choroid plexus (CP) is due to melanocytes, the signal would be elevated in Black/African American (B/AA) compared to White (W) participants. In addition, we examined whether CP signal affects measurements in adjacent regions, and whether correcting for spill-in effects has an influence on associations between hippocampus (HC) FTP and amyloid or cognition. Methods FTP race differences in 147 Harvard Aging Brain Study participants (23 B/AA, 124W) were examined in CP, HC, HC covaried for CP, amygdala, inferior temporal gyrus, entorhinal cortex, and fusiform regions. Associations between CP FTP and other regions-of-interest (ROIs) were probed to assess spill-in effects. A statistical regression approach to attenuate CP spill-in was tested by relating adjusted HC SUVR residuals and unadjusted HC SUVR to race, cognition and amyloid. All analyses were covaried for age, sex, education and amyloid deposition, and Bonferroni-corrected for multiple comparisons. Results B/AA individuals had elevated CP and HC SUVR (p < 0.007), whereas other ROI SUVR and HC SUVR covaried for CP SUVR did not show race differences (p > 0.05). CP SUVR was associated with HC SUVR (p < 10−14), but with no other ROI SUVR (p > 0.05). When adjusting HC SUVR for CP SUVR, no race differences in residual HC SUVR were detected, and relationships with amyloid and memory became apparent. Conclusion Melanocyte FTP binding may account partially for high CP signal. This off-target binding affects mainly HC FTP measurements, which should be interpreted with caution. PMID:29614677

  14. Factors affecting infection of corals and larval oysters by Vibrio coralliilyticus.

    PubMed

    Ushijima, Blake; Richards, Gary P; Watson, Michael A; Schubiger, Carla B; Häse, Claudia C

    2018-01-01

    The bacterium Vibrio coralliilyticus can threaten vital reef ecosystems by causing disease in a variety of coral genera, and, for some strains, increases in virulence at elevated water temperatures. In addition, strains of V. coralliilyticus (formally identified as V. tubiashii) have been implicated in mass mortalities of shellfish larvae causing significant economic losses to the shellfish industry. Recently, strain BAA-450, a coral pathogen, was demonstrated to be virulent towards larval Pacific oysters (Crassostrea gigas). However, it is unclear whether other coral-associated V. coralliilyticus strains can cause shellfish mortalities and if infections are influenced by temperature. This study compared dose dependence, temperature impact, and gross pathology of four V. coralliilyticus strains (BAA-450, OCN008, OCN014 and RE98) on larval C. gigas raised at 23°C and 27°C, and evaluated whether select virulence factors are required for shellfish infections as they are for corals. All strains were infectious to larval oysters in a dose-dependent manner with OCN014 being the most pathogenic and BAA-450 being the least. At 27°C, higher larval mortalities (p < 0.05) were observed for all V. coralliilyticus strains, ranging from 38.8-93.7%. Gross pathological changes to the velum and cilia occurred in diseased larvae, but there were no distinguishable differences between oysters exposed to different V. coralliilyticus strains or temperatures. Additionally, in OCN008, the predicted transcriptional regulator ToxR and the outer membrane protein OmpU were important for coral and oyster disease, while mannose sensitive hemagglutinin type IV pili were required only for coral infection. This study demonstrated that multiple coral pathogens can infect oyster larvae in a temperature-dependent manner and identified virulence factors required for infection of both hosts.

  15. Structurally distinct polycyclic aromatic hydrocarbons induce differential transcriptional responses in developing zebrafish

    PubMed Central

    Goodale, Britton C.; Tilton, Susan C.; Wilson, Glenn; Corvi, Margaret M.; Janszen, Derek B.; Anderson, Kim A.; Waters, Katrina M.; Tanguay, Robert L.

    2014-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment as components of fossil fuels and by-products of combustion. These multi-ring chemicals differentially activate the Aryl Hydrocarbon Receptor (AHR) in a structurally dependent manner, and induce toxicity via both AHR-dependent and-independent mechanisms. PAH exposure is known to induce developmental malformations in zebrafish embryos, and recent studies have shown cardiac toxicity induced by compounds with low AHR affinity. Unraveling the potentially diverse molecular mechanisms of PAH toxicity is essential for understanding the hazard posed by complex PAH mixtures present in the environment. We analyzed transcriptional responses to PAH exposure in zebrafish embryos exposed to benz(a)anthracene (BAA), dibenzothiophene (DBT) and pyrene (PYR) at concentrations that induced developmental malformations by 120 hours post-fertilization (hpf). Whole genome microarray analysis of mRNA expression at 24 and 48 hpf identified genes that were differentially regulated over time and in response to the three PAH structures. PAH body burdens were analyzed at both time points using GC-MS, and demonstrated differences in PAH uptake into the embryos. This was important for discerning dose-related differences from those that represented unique molecular mechanisms. While BAA misregulated the least number of transcripts, it caused strong induction of cyp1a and other genes known to be downstream of the AHR, which were not induced by the other two PAHs. Analysis of functional roles of misregulated genes and their predicted regulatory transcription factors also distinguished the BAA response from regulatory networks disrupted by DBT and PYR exposure. These results indicate that systems approaches can be used to classify the toxicity of PAHs based on the networks perturbed following exposure, and may provide a path for unraveling the toxicity of complex PAH mixtures. PMID:23656968

  16. Brain arterial aging and its relationship to Alzheimer dementia

    PubMed Central

    Honig, Lawrence; Elkind, Mitchell S.V.; Mohr, Jay P.; Goldman, James; Dwork, Andrew J.; Morgello, Susan; Marshall, Randolph S.

    2016-01-01

    Objective: To test the hypothesis that brain arterial aging is associated with the pathologic diagnosis of Alzheimer disease (AD). Methods: Brain large arteries were assessed for diameter, gaps in the internal elastic lamina (IEL), luminal stenosis, atherosclerosis, and lumen-to-wall ratio. Elastin, collagen, and amyloid were assessed with Van Gieson, trichrome, and Congo red staining intensities, and quantified automatically. Brain infarcts and AD (defined pathologically) were assessed at autopsy. We created a brain arterial aging (BAA) score with arterial characteristics associated with aging after adjusting for demographic and clinical variables using cross-sectional generalized linear models. Results: We studied 194 autopsied brains, 25 (13%) of which had autopsy evidence of AD. Brain arterial aging consisted of higher interadventitial and lumen diameters, thickening of the wall, increased prevalence of IEL gaps, concentric intima thickening, elastin loss, increased amyloid deposition, and a higher IEL proportion without changes in lumen-to-wall ratio. In multivariable analysis, a high IEL proportion (B = 1.96, p = 0.030), thick media (B = 3.50, p = 0.001), elastin loss (B = 6.16, p < 0.001), IEL gaps (B = 3.14, p = 0.023), and concentric intima thickening (B = 7.19, p < 0.001) were used to create the BAA score. Adjusting for demographics, vascular risk factors, atherosclerosis, and brain infarcts, the BAA score was associated with AD (B = 0.022, p = 0.002). Conclusions: Aging of brain large arteries is characterized by arterial dilation with a commensurate wall thickening, elastin loss, and IEL gaps. Greater intensity of arterial aging was associated with AD independently of atherosclerosis and brain infarcts. Understanding the drivers of arterial aging may advance the knowledge of the pathophysiology of AD. PMID:26984942

  17. Brain arterial aging and its relationship to Alzheimer dementia.

    PubMed

    Gutierrez, Jose; Honig, Lawrence; Elkind, Mitchell S V; Mohr, Jay P; Goldman, James; Dwork, Andrew J; Morgello, Susan; Marshall, Randolph S

    2016-04-19

    To test the hypothesis that brain arterial aging is associated with the pathologic diagnosis of Alzheimer disease (AD). Brain large arteries were assessed for diameter, gaps in the internal elastic lamina (IEL), luminal stenosis, atherosclerosis, and lumen-to-wall ratio. Elastin, collagen, and amyloid were assessed with Van Gieson, trichrome, and Congo red staining intensities, and quantified automatically. Brain infarcts and AD (defined pathologically) were assessed at autopsy. We created a brain arterial aging (BAA) score with arterial characteristics associated with aging after adjusting for demographic and clinical variables using cross-sectional generalized linear models. We studied 194 autopsied brains, 25 (13%) of which had autopsy evidence of AD. Brain arterial aging consisted of higher interadventitial and lumen diameters, thickening of the wall, increased prevalence of IEL gaps, concentric intima thickening, elastin loss, increased amyloid deposition, and a higher IEL proportion without changes in lumen-to-wall ratio. In multivariable analysis, a high IEL proportion (B = 1.96, p = 0.030), thick media (B = 3.50, p = 0.001), elastin loss (B = 6.16, p < 0.001), IEL gaps (B = 3.14, p = 0.023), and concentric intima thickening (B = 7.19, p < 0.001) were used to create the BAA score. Adjusting for demographics, vascular risk factors, atherosclerosis, and brain infarcts, the BAA score was associated with AD (B = 0.022, p = 0.002). Aging of brain large arteries is characterized by arterial dilation with a commensurate wall thickening, elastin loss, and IEL gaps. Greater intensity of arterial aging was associated with AD independently of atherosclerosis and brain infarcts. Understanding the drivers of arterial aging may advance the knowledge of the pathophysiology of AD. © 2016 American Academy of Neurology.

  18. In Vitro Cytotoxicity and Adaptive Stress Responses to Selected Haloacetic Acid and Halobenzoquinone Water Disinfection Byproducts.

    PubMed

    Procházka, Erik; Escher, Beate I; Plewa, Michael J; Leusch, Frederic D L

    2015-10-19

    The process of disinfecting drinking water inadvertently leads to the formation of numerous disinfection byproducts (DBPs). Some of these are mutagenic, genotoxic, teratogenic, and cytotoxic, as well as potentially carcinogenic both in vivo and in vitro. We investigated the in vitro biological activity of five DBPs: three monohaloacetic acids (monoHAAs) [chloroacetic acid (CAA), bromoacetic acid (BAA), and iodoacetic acid (IAA)] and two novel halobenzoquinones (HBQs) [2,6-dichloro-p-benzoquinone (DCBQ) and 2,6-dibromo-p-benzoquinone]. We focused particularly on cytotoxicity and induction of two adaptive stress response pathways: the oxidative stress responsive Nrf2/ARE and DNA-damage responsive p53 pathways. All five DBPs were cytotoxic to the Caco-2 cell line after a 4 h exposure, and all DBPs induced both of the adaptive stress response pathways, Nrf2/ARE and p53, in the micromolar range, as measured by two β-lactamase-based reporter gene assays. The decreasing order of potency for all three endpoints for the five DBPs was IAA ∼ BAA > DCBQ ∼ DBBQ > CAA. Induction of oxidative stress was previously proposed to be the molecular initiating event (MIE) for both classes of DBPs. However, comparing the levels of activation of the two pathways uncovered that the Nrf2/ARE pathway was the more sensitive endpoint for HAAs, whereas the p53 pathway was more sensitive in the case of HBQs. Therefore, the DNA damage-responsive p53 pathway may be an important piece of information to fill in a gap in the adverse outcome pathway framework for the assessment of HBQs. Finally, we cautiously compared the potential risk of the two novel HBQs using a benchmarking approach to that of the well-studied CAA, which suggested that their relative risk may be lower than that of BAA and IAA.

  19. Preliminary PCA/TT Results on MRO CRISM Multispectral Images

    NASA Astrophysics Data System (ADS)

    Klassen, David R.; Smith, M. D.

    2010-10-01

    Mars Reconnaissance Orbiter arrived at Mars in March 2006 and by September had achieved its science-phase orbit with the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) beginning its visible to near-infrared (VIS/NIR) spectral imaging shortly thereafter. One goal of CRISM is to fill in the spatial gaps between the various targeted observations, eventually mapping the entire surface. Due to the large volume of data this would create, the instrument works in a reduced spectral sampling mode creating "multispectral” images. From these data we can create image cubes using 64 wavelengths from 0.410 to 3.923 µm. We present here our analysis of these multispectral mode data products using Principal Components Analysis (PCA) and Target Transformation (TT) [1]. Previous work with ground-based images [2-5] has shown that over an entire visible hemisphere, there are only three to four meaningful components using 32-105 wavelengths over 1.5-4.1 µm the first two are consistent over all temporal scales. The TT retrieved spectral endmembers show nearly the same level of consistency [5]. The preliminary work on the CRISM images cubes implies similar results; three to four significant principal components that are fairly consistent over time. These components are then used in TT to find spectral endmembers which can be used to characterize the surface reflectance for future use in radiative transfer cloud optical depth retrievals. We present here the PCA/TT results comparing the principal components and recovered endmembers from six reconstructed CRISM multi-spectral image cubes. References: [1] Bandfield, J. L., et al. (2000) JGR, 105, 9573. [2] Klassen, D. R. and Bell III, J. F. (2001) BAAS 33, 1069. [3] Klassen, D. R. and Bell III, J. F. (2003) BAAS, 35, 936. [4] Klassen, D. R., Wark, T. J., Cugliotta, C. G. (2005) BAAS, 37, 693. [5] Klassen, D. R. (2009) Icarus, 204, 32.

  20. Physics Comes to Winnipeg: The 1909 Meeting of the British Association for the Advancement of Science

    ERIC Educational Resources Information Center

    Klassen, Stephen; Dietrich, Sarah

    2010-01-01

    History of science can be used to bring scientific concepts to school science in a way that humanizes the protagonists and provides an appropriate context. The authors have researched the 1909 meeting of the British Association for the Advancement of Science (BAAS) in Winnipeg, a significant event in the city's history that has remained largely…