Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| elemental analysis of the mycobacterium avium phagosome in balb/c mouse macrophages. | using a hard x-ray microprobe, we showed recently that in unstimulated peritoneal macrophages from c57bl/6 mice, the phagosome of pathogenic mycobacteria (mycobacterium tuberculosis and mycobacterium avium) can accumulate iron. we expanded our studies to the m. avium infection of peritoneal macrophages of balb/c mice that show a similar degree of m. tuberculosis and m. avium-related chronic disease, but a higher susceptibility towards other intracellular pathogens such as listeria monocytogenes, ... | 2006 | 16650826 |
| cytokine modulation of the innate immune response in feline immunodeficiency virus-infected cats. | in vitro data suggest that innate immune function in human immunodeficiency virus type 1-infected patients is compromised; however, in vivo studies are lacking. feline immunodeficiency virus (fiv) infection in cats provides an excellent model to explore innate immune function in vivo. the innate response against listeria monocytogenes is well understood, making it a useful immune probe. | 2006 | 16652280 |
| listeriosis due to infection with a catalase-negative strain of listeria monocytogenes. | a strain of listeria monocytogenes recovered from blood and cerebrospinal fluid had no detectable catalase activity, a characteristic used for primary identification. the sporadic occurrence of pathogenic catalase-negative strains highlights the need for a reconsideration of diagnostic criteria and questions the role of catalase in the pathogenesis of listeria infection. | 2006 | 16672441 |
| control of listeria spp. by competitive-exclusion bacteria in floor drains of a poultry processing plant. | in previous studies workers determined that two lactic acid bacterium isolates, lactococcus lactis subsp. lactis c-1-92 and enterococcus durans 152 (competitive-exclusion bacteria [ce]), which were originally obtained from biofilms in floor drains, are bactericidal to listeria monocytogenes or inhibit the growth of l. monocytogenes both in vitro and in biofilms at 4 to 37 degrees c. we evaluated the efficacy of these isolates for reducing listeria spp. contamination of floor drains of a plant in ... | 2006 | 16672472 |
| role of efflux pumps in adaptation and resistance of listeria monocytogenes to benzalkonium chloride. | in this study, potential mechanisms underlying resistance and adaptation to benzalkonium chloride (bc) in listeria monocytogenes were investigated. two groups of strains were studied. the first group consisted of strains naturally sensitive to bc which could be adapted to bc. the second group consisted of naturally resistant strains. for all adapted isolates, there was a correlation between the resistance to bc and ethidium bromide, but this was not the case for the naturally resistant isolates. ... | 2006 | 16672496 |
| listeric meningoencephalomyelitis in a cougar (felis concolor): characterization by histopathologic, immunohistochemical, and molecular methods. | listeria monocytogenes has been recognized as an important food-borne pathogen in animals. records of the disease caused by this bacterium in large felids are, however, rare. the nervous form of listeriosis was diagnosed in a 12-year-old male cougar (felis concolor) with a several-day history of neurologic disease characterized by excess salivation, head pressing, and circling that progressed to recumbency and death. microscopically, the main alteration in the brain and spinal cord was a variabl ... | 2006 | 16672590 |
| the bacterial quality of red meat and offal in casablanca (morocco). | the present study aimed to evaluate the bacteriological quality of beef (n = 52), lamb (n = 52) and beef offal (n = 52) marketed in casablanca, morocco. meat and offal samples (n = 156), were collected randomly from butcheries, supermarkets, and slaughterhouses. two sampling periods were considered, one during the hot season and the second one during the cold season. the samples were analyzed for the presence of the following bacteria: escherichia coli, coagulase-positive staphylococcus, clostri ... | 2006 | 16676376 |
| bactericidal effects of cao (scallop-shell powder) on foodborne pathogenic bacteria. | this study was investigated the bactericidal effects of calcium oxide (cao) on three common foodborne pathogenic bacteria: escherichia coli, listeria monocytogenes, and salmonella typhimurium. each bacteria level was determined in a cao solution (0.01, 0.03, 0.05, 0.10, 0.15, and 0.20% [w/v]) exposed for either 15 sec, 30 sec, 1 min, 2 min, 3 min, 5 min, 10 min, or 30 min. all three bacteria were not greatly affected by cao solutions at concentrations of 0.01 and 0.03%, however, the decline of e ... | 2006 | 16681035 |
| identification of small hfq-binding rnas in listeria monocytogenes. | the rna-binding protein hfq plays important roles in bacterial physiology and is required for the activity of many small regulatory rnas in prokaryotes. we have previously shown that hfq contributes to stress tolerance and virulence in the gram-positive human pathogen listeria monocytogenes. in the present study, we performed coimmunoprecipitations followed by enzymatic rna sequencing to identify hfq-binding rna molecules in l. monocytogenes. the approach resulted in the discovery of three small ... | 2006 | 16682563 |
| identification, subtyping and virulence determination of listeria monocytogenes, an important foodborne pathogen. | listeria monocytogenes is an opportunistic intracellular pathogen that has become an important cause of human foodborne infections worldwide. given its close relationship to other listeria species and its tendency to produce non-specific clinical symptoms, the availability of rapid, sensitive and specific diagnostic tests for the differentiation of l. monocytogenes from other listeria species is helpful for selecting appropriate treatment regimens. in addition, with l. monocytogenes comprising a ... | 2006 | 16687581 |
| escherichia coli interactions with acanthamoeba: a symbiosis with environmental and clinical implications. | the ability of acanthamoeba to feed on gram-negative bacteria, as well as to harbour potential pathogens, such as legionella pneumophila, coxiella burnetii, pseudomonas aeruginosa, vibrio cholerae, helicobacter pylori, listeria monocytogenes and mycobacterium avium, suggest that both amoebae and bacteria are involved in complex interactions, which may play important roles in the environment and in human health. in this study, acanthamoeba castellanii (a keratitis isolate belonging to the t4 geno ... | 2006 | 16687585 |
| surrogates for validation of electron beam irradiation of foods. | the aim of this study was to identify a potential surrogate to describe the radiation sensitivity of the most common pathogens encountered in fruits. three pathogens: escherichia coli o157:h7 933, listeria monocytogenes atcc 51414, and salmonella poona, and five non-pathogens: e. coli k-12 mg1655, listeria innocua seeliger 1983 (nrrl b-33003 and nrrl b-33014), enterobacter aerogenes, and salmonella lt2 were inoculated (populations of 10(7)-10(9) cfu/ml) into model food systems (10% w/w gelatin) ... | 2006 | 16690150 |
| genetic relatedness between listeria monocytogenes isolates from seafood and humans using pfge and rep-pcr. | listeria monocytogenes has been isolated from catfish and various non-catfish seafoods. despite progress that was made to understand the relationship between l. monocytogenes isolated from seafood and humans, no study has emphasized the genetic relatedness between catfish and non-catfish seafood and human isolates. the objectives of this study were to (1) investigate the genetic relationship between l. monocytogenes isolates from catfish, non-catfish seafood and humans using pulsed-field gel ele ... | 2006 | 16690152 |
| efficiency of electrolyzed oxidizing water on reducing listeria monocytogenes contamination on seafood processing gloves. | food processing gloves are typically used to prevent cross-contamination during food preparation. however, gloves can be contaminated with microorganisms and become a source of contamination. this study investigated the survival of listeria monocytogenes on gloves and determined the efficacy of electrolyzed oxidizing (eo) water for reducing l. monocytogenes contamination on seafood processing gloves. three types of reusable gloves (natural rubber latex, natural latex, and nitrile) and two types ... | 2006 | 16690154 |
| dynamic modeling of listeria monocytogenes growth in pasteurized milk. | the development and validation of a dynamic model for predicting listeria monocytogenes growth in pasteurized milk stored at both static and dynamic temperature conditions. | 2006 | 16696676 |
| a comparison of selected methods for measuring the virulence properties of listeria spp. | the comparative ability of different methods to assess virulence of listeria species was investigated in ten listeria strains. all strains were initially subjected to pulsed-field gel electrophoresis analysis to determine their relatedness. virulence characteristics were subsequently tested for by (i) determining the presence of six virulence genes by polymerase chain reaction; (ii) testing for the production of listeriolysin o, phosphatidylcholine phospholipase c, and phosphatidylinositol-speci ... | 2006 | 16699580 |
| fitness of human enteric pathogens on plants and implications for food safety. | the continuous rise in the number of outbreaks of foodborne illness linked to fresh fruit and vegetables challenges the notion that enteric pathogens are defined mostly by their ability to colonize the intestinal habitat. this review describes the epidemiology of produce-associated outbreaks of foodborne disease and presents recently acquired knowledge about the behavior of enteric pathogens on plants, with an emphasis on salmonella enterica, escherichia coli o157:h7, and listeria monocytogenes. ... | 2006 | 16704355 |
| overexpression of prfa leads to growth inhibition of listeria monocytogenes in glucose-containing culture media by interfering with glucose uptake. | listeria monocytogenes strains expressing high levels of the virulence regulator prfa (mutant prfa* or wild-type prfa) show strong growth inhibition in minimal media when they are supplemented with glucose but not when they are supplemented with glucose-6-phosphate compared to the growth of isogenic strains expressing low levels of prfa. a significantly reduced rate of glucose uptake was observed in a prfa*-overexpressing strain growing in lb supplemented with glucose. comparative transcriptome ... | 2006 | 16707681 |
| listeria monocytogenes: a multifaceted model. | the opportunistic intracellular pathogen listeria monocytogenes has become a paradigm for the study of host-pathogen interactions and bacterial adaptation to mammalian hosts. analysis of l. monocytogenes infection has provided considerable insight into how bacteria invade cells, move intracellularly, and disseminate in tissues, as well as tools to address fundamental processes in cell biology. moreover, the vast amount of knowledge that has been gathered through in-depth comparative genomic anal ... | 2006 | 16710323 |
| the specific and essential role of mavs in antiviral innate immune responses. | the mitochondrial antiviral signaling protein (mavs) mediates the activation of nfkappab and irfs and the induction of interferons in response to viral infection. in vitro studies have also suggested that mavs is required for interferon induction by cytosolic dna, but the in vivo evidence is lacking. by generating mavs-deficient mice, here we show that loss of mavs abolished viral induction of interferons and prevented the activation of nfkappab and irf3 in multiple cell types, except plasmacyto ... | 2006 | 16713980 |
| differential requirements for soluble and transmembrane tumor necrosis factor in the immunological control of primary and secondary listeria monocytogenes infection. | the relative contributions of transmembrane tumor necrosis factor (memtnf) and soluble tumor necrosis factor (soltnf) in innate and adaptive immunity are poorly defined. we examined the capacities of wild-type (wt) mice, tnf-/- mice, and memtnf mice, which express only transmembrane tnf, to control primary and secondary listeria monocytogenes infections. soluble tnf was not required for induction or maintenance of protective immunity against a low-dose (200-cfu) listeria infection. in contrast t ... | 2006 | 16714545 |
| interleukin 15-dependent crosstalk between conventional and plasmacytoid dendritic cells is essential for cpg-induced immune activation. | the function of interleukin 15 (il-15) in unmethylated cpg oligodeoxynucleotide (cpg)-induced immune responses remains unknown. here, in response to cpg, both wild-type and natural killer cell-depleted mice produced il-12 and became resistant to a lethal dose of listeria monocytogenes. in contrast, cpg-treated il-15-deficient mice produced little il-12 and succumbed to l. monocytogenes. cpg-stimulated conventional dendritic cells (cdcs) were the main producers of both il-15 and il-12, but cdcs d ... | 2006 | 16715101 |
| mechanism of action of spanish oregano, chinese cinnamon, and savory essential oils against cell membranes and walls of escherichia coli o157:h7 and listeria monocytogenes. | the mechanism of the antimicrobial action of spanish oregano (corydothymus capitatus), chinese cinnamon (cinnamomum cassia), and savory (satureja montana) essential oils against cell membranes and walls of bacteria was studied by the measurement of the intracellular ph and atp concentration, the release of cell constituents, and the electronic microscopy observations of the cells when these essential oils at their mics were in contact with escherichia coli o157:h7 and listeria monocytogenes. e. ... | 2006 | 16715803 |
| inhibitory effect of select nitrocompounds on growth and survivability of listeria monocytogenes in vitro. | we report the effects of 2-nitro-1-propanol (2npoh), 2-nitroethanol (2neoh), and nitroethane (ne) on growth and survivability of listeria monocytogenes. in all cases, inhibition was greatest with 2npoh and least with ne. for example, specific growth rates of l. monocytogenes strain 18 declined (p < 0.05) 76, 60, and 29% from controls during aerobic culture at 37 degrees c in brain heart infusion broth containing 10 mm 2npoh, 2neoh, or ne, respectively. mean specific growth rate for the controls ... | 2006 | 16715805 |
| bacteriocin activity by lactobacillus curvatus cwbi-b28 to inactivate listeria monocytogenes in cold-smoked salmon during 4 degrees c storage. | the inhibition effectiveness of a bacteriocin produced by lactobacillus curvatus cwbi-b28 against listeria monocytogenes was investigated in cold-smoked salmon during storage at 4 degrees c. three bacteriocin-based strategies for the control of l. monocytogenes in foods (i.e., producing bacteriocin in situ, spraying with partially purified bacteriocin, and packaging in bacteriocin-coated plastic film), plus a newly developed method that uses cell-adsorbed bacteriocin (i.e., a suspension of produ ... | 2006 | 16715806 |
| thermal inactivation studies of escherichia coli o157:h7, salmonella, and listeria monocytogenes in ready-to-eat chicken-fried beef patties. | thermal inactivation studies were used to determine the d- and z-values of escherichia coli o157:h7, salmonella, and listeria monocytogenes in ready-to-eat chicken-fried beef patties. inoculated meat was packaged in sterile bags, which were immersed in a circulated water bath and held at 55, 57.5, 60, 62.5, 65, 67.5, and 70 degrees c for different lengths of time. d- and z-values were determined with a linear regression model. average d-values at temperatures 55 to 70 degrees c were 27.62 to 0.0 ... | 2006 | 16715808 |
| pathogen survival in chorizos: ecological factors. | this study addressed health risks from ethnic sausages produced on a small scale, without inspection, in california and elsewhere. mexican-style chorizo, a raw pork sausage that is not cured, fermented, or smoked, was contaminated experimentally in the batter with escherichia coli o157:h7, listeria monocytogenes, or salmonella serotypes and stuffed into natural casings. formulations were based on a market survey in california. physical parameters that were controlled were ph, water activity (a(w ... | 2006 | 16715809 |
| rabbit meat as a source of bacterial foodborne pathogens. | even though worldwide production of rabbit meat is >1,000,000 tons, little information is available for rabbit meat microbiology. this study provides data on the prevalence of salmonella, escherichia coli o157:h7, yersinia enterocolitica, listeria spp., motile aeromonas spp., and staphylococcus aureus on rabbit meat. a total of 24 rabbit carcasses from two abattoirs and 27 rabbit meat packages from supermarket displays were examined. in addition to culturing methods, associated virulence genes w ... | 2006 | 16715811 |
| monitoring the microbial populations and temperatures of fresh broccoli from harvest to retail display. | microbial populations and the temperature of fresh broccoli were monitored at several steps of a supply chain by sampling 33 distinct lots of locally grown produce over two seasons during harvest, storage, wholesale handling, and retail display. imported broccoli was also sampled, but only at retail display. microbiological analyses were conducted on the florets of 201 local and 60 imported broccoli samples to determine populations of total aerobic bacteria (aerobic colony count), fecal coliform ... | 2006 | 16715813 |
| lactobacillus plantarum gene clusters encoding putative cell-surface protein complexes for carbohydrate utilization are conserved in specific gram-positive bacteria. | genomes of gram-positive bacteria encode many putative cell-surface proteins, of which the majority has no known function. from the rapidly increasing number of available genome sequences it has become apparent that many cell-surface proteins are conserved, and frequently encoded in gene clusters or operons, suggesting common functions, and interactions of multiple components. | 2006 | 16723015 |
| control of listeria monocytogenes virulence by 5'-untranslated rna. | the gram-positive bacterium listeria monocytogenes uses a wide range of virulence factors for its pathogenesis. expression of five of these factors has previously been shown to be subjected to post-transcriptional regulation as a result of their long 5'-untranslated region (5'-utr). we have investigated the presence of 5'-utrs among the other known virulence genes and genes that encode putatively virulence-associated surface proteins. our results strongly suggest that l. monocytogenes controls m ... | 2006 | 16730443 |
| listeria pleuritis 1 week after lung transplantation. | listeria monocytogenes is an important bacterial pathogen in immunocompromised patients, the elderly, pregnant women and transplant patients, but until now it has not been reported in lung transplants. we report the first case of listeriosis in a lung transplant recipient who presented with a pleural effusion 8 days after transplantation. after the introduction of a thorax drain and the administration of intravenous antibiotics during 3 weeks, the patient recovered completely. this case highligh ... | 2006 | 16730581 |
| listeriolysin o derived from listeria monocytogenes inhibits the effector phase of an experimental allergic rhinitis induced by ovalbumin in mice. | listeriolysin o (llo) derived from listeria monocytogenes is highly capable of inducing interleukin (il)-12, il-18 and interferon (ifn)-gamma, and facilitates the generation of th1 cells. we have recently shown that recombinant llo (rllo) inhibits generation of ovalbumin (ova)-specific th2 immune response by skewing maturation of antigen-specific t cells into th1 cells. in the present study, we investigated the effect of rllo on the effector phase of th2-dependent allergic rhinitis in balb/c mic ... | 2006 | 16734617 |
| contributions of listeria monocytogenes sigmab and prfa to expression of virulence and stress response genes during extra- and intracellular growth. | listeria monocytogenes sigmab and prfa are pleiotropic regulators of stress response and virulence gene expression. quantitative rt-pcr (qrt-pcr) was used to measure transcript levels of sigmab- and prfa-dependent genes in exponential-phase l. monocytogenes wild-type and deltasigb strains as well as in bacteria exposed to environmental stresses (0.3 m nacl or growth to stationary phase) or present in the vacuole or cytosol of human intestinal epithelial cells. stationary-phase or nacl-exposed l. ... | 2006 | 16735745 |
| panr1, a dominant negative missense allele of the gene encoding tnf-alpha (tnf), does not impair lymphoid development. | a dominant hypomorphic allele of tnf, panr1, was identified in a population of g(1) mice born to n-ethyl-n-nitrosourea-mutagenized sires. macrophages from homozygotes produced no detectable tnf bioactivity, although normal quantities of immunoreactive tnf were secreted. the phenotype was confined to a critical region on mouse chromosome 17, and then ascribed to a c-->a transversion at position 3480 of the tnf gene, corresponding to the amino acid substitution p138t. as a result of subunit exchan ... | 2006 | 16751399 |
| a novel functional t cell hybridoma recognizes macrophage cell death induced by bacteria: a possible role for innate lymphocytes in bacterial infection. | we have established a novel tcralphabeta (tcrvbeta6)(+)cd4(-)cd8(-) t cell hybridoma designated b6ho3. when the b6ho3 cells were cocultured with bacterial-infected j774 macrophage-like cells, ifn-gamma production by b6ho3 cells was triggered through direct cell-cell contact with dying j774 cells infected with listeria monocytogenes (lm), shigella flexneri, or salmonella typhimurium that expressed the type iii secretion system, but not with intact j774 cells infected with heat-killed lm, nonhemol ... | 2006 | 16751404 |
| differential inla and inlb expression and interaction with human intestinal and liver cells by listeria monocytogenes strains of different origins. | in this study, a number of listeria monocytogenes strains of different origins were evaluated for in vitro invasion capacity for various human cell types (monocytic thp-1, enterocytic caco-2, and hepatocytic hepg2 cells) and for expression levels of specific virulence genes. for thp-1 cells, no differences between clinical and nonclinical l. monocytogenes strains in invasion capacity or in production of the proinflammatory cytokine interleukin-8 (il-8) were observed, whereas for the caco-2 and h ... | 2006 | 16751490 |
| a cold-sensitive listeria monocytogenes mutant has a transposon insertion in a gene encoding a putative membrane protein and shows altered (p)ppgpp levels. | a cold-sensitive listeria monocytogenes mutant designated cld-14 was obtained by transposon tn917 mutagenesis. the gene interrupted by tn917 in cld-14 was the l. monocytogenes lmof2365_1485 homolog, which exhibits 45.7% homology to the bacillus subtilis yqff locus. lmof2365_1485, here designated pgph, encodes a putative integral membrane protein with a predicted molecular mass of 81 kda. pgph is predicted to contain a conserved n-terminal signal peptide sequence, seven transmembrane helices, and ... | 2006 | 16751502 |
| one group of genetically similar listeria monocytogenes strains frequently dominates and persists in several fish slaughter- and smokehouses. | contamination of foods with the human pathogen listeria monocytogenes may occur during processing, and the purpose of this study was to determine whether genetically similar strains colonize different processing plants or whether specific persistent strains are unique to each processing plant. we hypothesized that specific l. monocytogenes strains may be better adapted to specific environmental niches in the processing environment. l. monocytogenes contamination patterns were identified by the c ... | 2006 | 16751546 |
| immobilization and detection of listeria monocytogenes. | a procedure was developed for immobilization of listeria monocytogenes cells on metal hydroxides coupled with detection and enumeration using an automated optical system. the results of the immobilization procedure (<1 h) and detection during overnight incubation agreed with calculated plate counts, and this technique is simple and rapid and provides samples that are ready for confirmation of the presence of the pathogen by rapid methods. | 2006 | 16751561 |
| an outbreak of iritis and uveitis in dairy cattle at pasture associated with the supplementary feeding of baleage. | 2006 | 16751847 | |
| way-202196, a selective estrogen receptor-beta agonist, protects against death in experimental septic shock. | to determine the effect of an estrogen receptor-beta selective agent in experimental models of systemic infection and sepsis. | 2006 | 16755255 |
| rapid discrimination of listeria monocytogenes strains by microtemperature gradient gel electrophoresis. | microtemperature gradient gel electrophoresis (mu-tgge) was examined for use for the rapid subtyping of listeria monocytogenes strains. comparison of genomes between l. monocytogenes strains f2365 and h7858 identified a sequence encoding a portion of the prt/pts system iia 2 protein domain as appropriate for mu-tgge analysis. thirty-one strains belonging to 10 different serovar types were tested by pcr, and sequence analysis of the amplified products revealed that the strains comprise 11 groups. ... | 2006 | 16757621 |
| biochemical characteristics of chitosanase from the indonesian bacillus licheniformis mb-2. | bacillus licheniformis mb-2, isolated from a hot spring water in manado, indonesia, secreted a unique chitosanase. media consisted of 0.24% chitosan, 0.25% casiton, 1% mgso4, 1.4% k2hpo4, 0.02% cacl2 x 2h2o, 0.002% feso4 x 7h2o (w/v) was used for enzyme production. purification of the enzyme through the hydrophobic interaction chromatography system (butyl sepharose 4 ff) resulted in two major active fractions; the f2 fraction was shown as a single band at both sodium dodecyl sulfate-polyacrylami ... | 2006 | 16757796 |
| listeria brain abscess, pneumocystis pneumonia and kaposi's sarcoma after temozolomide. | a 55-year-old man with glioblastoma multiforme was treated with continuous, dose-dense temozolomide. this therapy was curtailed after three cycles because of nausea, asthenia, and neuropsychological deterioration. during a subsequent course of radiotherapy, the patient developed fever, headaches, and cutaneous lesions. | 2006 | 16757971 |
| [microbiological characterization of listeria monocytogenes isolated from different sources in the primorsky territory]. | the results of the bacteriological study of material, taken from humans, rodents, hydro-bios and environmental objects (including foodstuffs) in the primorsky territory, for the presence of l. monocytogenes bacteria are given. 83 bacterial strains of the genus listeria were isolated. as revealed in this study, 25 of these strains belonged to l. monocytogenes (30.12%), 8 strains--to l. innocua (9.6%), 6 strains--to l. seeligeri (7.2%) and 2 strains--to l. ivanovii (2.4%). the greatest number of l ... | 2006 | 16758889 |
| listeriosis associated with gorgonzola (italian blue-veined cheese). | we describe a case of listeriosis in italy associated with the consumption of cheese. opened samples of two brands of gorgonzola (italian blue-veined cheese; referred to as brands "b" and "c") were collected from the patient's refrigerator. unopened samples of the brand suspected to be the source of infection (brand b) were taken from the store where the cheese had been purchased, other local stores, and the production plant. listeria monocytogenes serotype 1/2b was isolated from the patient and ... | 2006 | 16761945 |
| characterization of a spontaneous, pressure-tolerant listeria monocytogenes scott a ctsr deletion mutant. | a spontaneous, pressure-tolerant mutant of listeria monocytogenes scott a, designated 2-1, was isolated after several rounds of pressure treatments at 500 mpa for 10 min. mutant 2-1 was almost 100,000-fold more resistant than the wild type to a pressure of 350 mpa, and about 100-fold more resistant to 450 mpa when pressurized in growth medium. approximately ten times more mutant cells than wild-type cells survived a 20-min exposure to 55 degrees c, and the mutant appears also to be more resistan ... | 2006 | 16761946 |
| simultaneous assessment of antigen-stimulated cytokine production and memory subset composition of memory cd8 t cells. | the functional identification of antigen-specific cd8 t cell populations is critical to understanding host responses to infection by intracellular pathogens. furthermore, assessing the properties of protective memory cd8 t cell populations generated by immunization is necessary in the rational design of vaccines. recently, a classification scheme was proposed in which memory cd8 t cells were divided into one of two distinct subsets, based on cd62l expression, that have different functional prope ... | 2006 | 16762359 |
| effect of the inoculum size on listeria monocytogenes growth in structured media. | obtaining quantitative data concerning the relative impact of various factors that may influence bacterial growth is of great importance for microbial risk assessment and predictive microbiology. the objective of this work was to investigate the effect of the initial listeria monocytogenes density on all the growth parameters of this pathogen (lag phase duration, growth rate and maximum population density attained) on a sterile solid model system mimicking smoked fishery products, and in real co ... | 2006 | 16762438 |
| low virulence but potentially fatal outcome-listeria ivanovii. | of the six known species of listeria, listeria monocytogenes is classified as the only human pathogen causing listeriosis, a highly fatal, opportunistic infection contracted via food. listeria ivanovii is the only other pathogenic species of the genus and is considered to be specific to ruminants, except for extremely rare cases of infection in humans. we report here on a 64-year-old male patient with l. ivanovii who responded favorably to treatment with intravenous ampicillin. | 2006 | 16762780 |
| disruption of escherichia coli, listeria monocytogenes and lactobacillus sakei cellular membranes by plant oil aromatics. | the role of membrane disruption in the bactericidal activity of the plant oil aromatic compounds eugenol, carvacrol and cinnamaldehyde was investigated using confocal laser scanning microscopy, changes in atp levels and cell viability. in 25 mm hepes buffer ph 7 at 20 degrees c, 10 mm eugenol or carvacrol increased uptake of propidium iodide by escherichia coli, listeria monocytogenes and lactobacillus sakei over a 10-min period. the same treatments resulted in lowered viability, rapid depletion ... | 2006 | 16417936 |
| adhesion characteristics of listeria adhesion protein (lap)-expressing escherichia coli to caco-2 cells and of recombinant lap to eukaryotic receptor hsp60 as examined in a surface plasmon resonance sensor. | listeria adhesion protein (lap) is an important adhesion factor in listeria monocytogenes and interacts with its cognate receptor, mammalian heat shock protein 60 (hsp60). the genetic identity of lap was determined to be alcohol acetaldehyde dehydrogenase (aad). a recombinant escherichia coli strain expressing aad confirmed the involvement of aad in adhesion to caco-2 cells. binding kinetics (ka) of recombinant lap (rlap) to hsp60 was examined in a surface plasmon resonance sensor and was determ ... | 2006 | 16499624 |
| bayesian synthesis of a pathogen growth model: listeria monocytogenes under competition. | the bayesian synthesis method is applied to data from two studies of listeria monocytogenes grown in broth monocultures to draw inferences about the joint distribution of two baranyi growth model parameters-lag time and maximum specific growth rate. the resultant joint distribution is then combined with prior distributions for the initial and maximum pathogen density parameters under competitive growth conditions. finally, the pathogen growth model is updated using the sampling/importance resamp ... | 2006 | 16499986 |
| autoinducer-2 bioassay is a qualitative, not quantitative method influenced by glucose. | autoinducer-2 (ai-2) is a cell-to-cell signaling molecule which is thought to be utilized for quorum sensing processes by a variety of prokaryotic species. this molecule is usually detected using a so-called autoinducer bioassay, which relies on the ability of a vibrio harveyi reporter strain to produce light in response to ai-2. however, as previously reported, the presence of glucose in the sample can inhibit the bioluminescence of the reporter strain, a fact that is often ignored by investiga ... | 2006 | 16564586 |
| secondary memory cd8+ t cells are more protective but slower to acquire a central-memory phenotype. | the formation of memory cd8 t cells is an important goal of vaccination. however, although widespread use of booster immunizations in humans generates secondary and tertiary cd8 t cell memory, experimental data are limited to primary cd8 t cell memory. here, we show that, compared with primary memory cd8 t cells, secondary memory cd8 t cells exhibit substantially delayed conversion to a central-memory phenotype, as determined by cd62l expression and interleukin (il)-2 production. this delayed co ... | 2006 | 16567385 |
| multiplex real-time single nucleotide polymorphism detection and quantification by quencher extension. | multiplex quencher extension (multiplex-qext) is a novel closed tube single-step method for detection and quantification of several single nucleotide polymorphisms (snps) simultaneously. the principle of multiplex-qext is that 5' reporter-labeled probes are 3' single-base-extended with tamra dideoxy nucleotides if the respective snp alleles are present. tamra can serve as either an energy acceptor (quencher-based detection) or donor [fluorescence resonance energy transfer (fret)-based detection] ... | 2006 | 16568821 |
| in vivo bactofection: listeria can function as a dna-cancer vaccine. | the development of an effective therapeutic vaccine to induce cancer-specific immunity remains an unsolved yet pressing priority requiring novel vaccine strategies. here we have generated a series of vaccines in which bacteria deliver a plasmid encoding a tumor antigen under the control of a mammalian promoter in an attempt to induce an antitumor immune response. utilizing a plasmid release mechanism involving the suicide of the carrier bacteria, we were able to engineer listeria monocytogenes t ... | 2006 | 16569193 |
| bac 32, a novel bacteriocin widely disseminated among clinical isolates of enterococcus faecium. | a total of 636 vancomycin-resistant enterococcus faecium (vre) isolates that had been obtained between 1994 and 1999 from the medical school hospital of the university of michigan, ann arbor, were tested for bacteriocin production. two hundred seventy-seven (44%) of the strains were bacteriocinogenic; and 193 of these exhibited activity against enterococcus faecium, enterococcus hirae, and enterococcus durans. strain vre200 harbors the highly efficient conjugative gentamicin resistance plasmid p ... | 2006 | 16569830 |
| n-3 pufa fail to affect in vivo, antigen-driven cd8+t-cell proliferation in the spleen of naïve mice. | one of the most frequently reported immunomodulatory actions of n-3 pufa is their ability to diminish in vitro lymphocyte proliferation. the purpose of this study was to determine if n-3 pufa intake affects the kinetics or magnitude of the antigen-driven expansion of cd8(+)t-lymphocytes in vivo. in this study we utilized a well-characterized model of t-cell immunity (i.e. infection with the intracellular bacterium, listeria monocytogenes). weanling balb/c mice were fed one of two experimental di ... | 2006 | 16571165 |
| [investigation of relationships between marine diatoms and the bacterium listeria monocytogenes]. | relationships between marine diatoms and the bacterium listeria monocytogenes have been studied by routine algological methods and high-resolution video-enhanced differential interference contrast light microscopy. the study showed that the relationship between the listeria and the benthic diatom navicula sp. has a parasitic character, whereas the relationship between the listeria and the planktonic diatom phaeodactylum tricornutum is protocooperative. | 2006 | 16579449 |
| associations among listeria monocytogenes genotypes and distinct clinical manifestations of listeriosis in cattle. | to determine whether specific strains of listeria monocytogenes, as determined by genetic characteristics and virulence phenotypes, were associated with distinct clinical manifestations of listeriosis in cattle and thus may potentially have tissue specificity. | 2006 | 16579754 |
| recombinant escherichia coli expressing invasin targets the peyer's patches: the basis for a bacterial formulation for oral vaccination. | we have investigated the tropism of nonpathogenic recombinant invasive escherichia coli in the gastrointestinal tract and the efficacy of this invasive e. coli as an oral vaccine for cancer immunotherapy. e. coli expressing invasin from yersinia pseudotuberculosis selectively invade nonphagocytic cells in which beta(1)-integrin is expressed and accessible. following internalization the e. coli are degraded in the phagosome. coexpression of listeriolysin o (llo) mediates release of the content of ... | 2006 | 16581299 |
| co-detection of bartonella henselae, borrelia burgdorferi, and anaplasma phagocytophilum in ixodes pacificus ticks from california, usa. | presence of bartonella dna was explored in 168 questing adult ixodes pacificus ticks from santa cruz county, california. bartonella henselae type i dna was amplified from 11 ticks (6.55%); previously, two (1.19%) were found to be infected with borrelia burgdorferi and five (2.98%) with anaplasma phagocytophilum. detection of b. henselae was not dependent on co-infection. the present study offers additional evidence that ixodes spp. ticks may act as hosts and possibly vectors for b. henselae. | 2006 | 16584332 |
| dependence of the lethal effect of pore-forming haemolysins of gram-positive bacteria on cytolytic activity. | among bacterial haemolysins, cholesterol-dependent cytolysins (cdcs) produced by various gram-positive bacteria are known to exhibit a lethal activity in mice. in this study, recombinant cdcs of streptolysin o, pneumolysin, ivanolysin o, listeriolysin o and several listeriolysin o mutants were constructed and the relationship between cytolytic activity and the lethal activity of each recombinant protein in mice was examined. specific activity for cytolysis was determined by a quantitative haemol ... | 2006 | 16585635 |
| construction and analysis of fractional multifactorial designs to study attachment strength and transfer of listeria monocytogenes from pure or mixed biofilms after contact with a solid model food. | the aim of this study was to establish which of seven factors influence the adhesion strength and hence bacterial transfer between biofilms containing listeria monocytogenes (pure and two-species biofilms) and tryptone soya agar (tsa) as a solid organic surface. the two-species biofilms were made of l. monocytogenes and one of the following species of bacteria: the nonpathogenic organisms kocuria varians, pseudomonas fluorescens, and staphylococcus sciuri and ccl 63, an unidentified gram-negativ ... | 2006 | 16597925 |
| bioenergetic mechanism for nisin resistance, induced by the acid tolerance response of listeria monocytogenes. | this study examined the bioenergetics of listeria monocytogenes, induced to an acid tolerance response (atr). changes in bioenergetic parameters were consistent with the increased resistance of atr-induced (atr(+)) cells to the antimicrobial peptide nisin. these changes may also explain the increased resistance of l. monocytogenes to other lethal factors. atr(+) cells had lower transmembrane ph (deltaph) and electric potential (deltapsi) than the control (atr(-)) cells. the decreased proton moti ... | 2006 | 16597957 |
| assessment of the roles of luxs, s-ribosyl homocysteine, and autoinducer 2 in cell attachment during biofilm formation by listeria monocytogenes egd-e. | luxs is responsible for the production of autoinducer 2 (ai-2), which is involved in the quorum-sensing response of vibrio harveyi. ai-2 is found in several other gram-negative and gram-positive bacteria and is therefore considered a good candidate for an interspecies communication signal molecule. in order to determine if this system is functional in the gastrointestinal pathogen listeria monocytogenes egd-e, an ai-2 bioassay was performed with culture supernatants. the results indicated that t ... | 2006 | 16597969 |
| novel luciferase reporter system for in vitro and organ-specific monitoring of differential gene expression in listeria monocytogenes. | in this paper we describe construction of a luciferase-based vector, ppl2lux, and use of this vector to study gene expression in listeria monocytogenes. ppl2lux is a derivative of the listerial integration vector ppl2 and harbors a synthetic luxabcde operon encoding a fatty acid reductase complex (luxcde) involved in synthesis of the fatty aldehyde substrate for the bioluminescence reaction catalyzed by the luxab luciferase. we constructed ppl2lux derivatives in which the seca and hlya promoters ... | 2006 | 16597994 |
| short communication: effect of exopolysaccharide isolated from "viili" on the adhesion of probiotics and pathogens to intestinal mucus. | the strong ropy character of the scandinavian fermented milk viili is conferred by the exopolysaccharides (eps) produced by lactococcal strains. these biopolymers can be responsible for some health benefits. we have assessed the influence of the eps fraction isolated from commercial viili on the adhesion of some probiotics and pathogens to human intestinal mucus. concentrations of viili eps greater than 0.1 mg/ml promoted a decrease in adherence of bifidobacterium lactis bb12 and lactobacillus r ... | 2006 | 16772550 |
| a survey of foodborne pathogens in bulk tank milk and raw milk consumption among farm families in pennsylvania. | a 2-part study was conducted to determine the risk of exposure to human pathogens from raw milk. the first part of the study focused on determining raw milk consumption habits of dairy producers. a total of 248 dairy producers from 16 counties in pennsylvania were surveyed. overall, 105 (42.3%) of the 248 dairy producers consumed raw milk and 170 (68.5%) of the 248 dairy producers were aware of foodborne pathogens in raw milk. dairy producers who were not aware of foodborne pathogens in raw milk ... | 2006 | 16772561 |
| invasive listeria monocytogenes infections in the netherlands, 1995-2003. | in order to add to the limited data available about the incidence of invasive listeria monocytogenes infection in the netherlands, two studies were conducted. in the first study, data on hospital patients with listeriosis in the period 1995-2003 were obtained from the national medical registration (study 1). in the second study, hospital discharge letters for patients whose listeria isolates were received by the netherlands reference laboratory for bacterial meningitis (nrlbm) in the period 1999 ... | 2006 | 16773392 |
| listeriolysin o: a key protein of listeria monocytogenes with multiple functions. | cholesterol-dependent cytolysins (cdcs) are produced by a large number of pathogenic gram-positive bacteria. most of these single-chain proteins are secreted in the extracellular medium. among the species producing cdcs, only two species belonging to the genus listeria (listeria monocytogenes and listeria ivanovii) are able to multiply intracellularly and release their toxins in the phagosomal compartment of the infected host cell. this review provides an updated overview on the importance of li ... | 2006 | 16774585 |
| purification and characterization of a heat-stable serine protease inhibitor from the tubers of new potato variety "golden valley". | potide-g, a small (5578.9 da) antimicrobial peptide, was isolated from potato tubers (solanum tuberosum l. cv. golden valley) through extraction of the water-soluble fraction, dialysis, ultrafiltration and deae-cellulose and c18 reverse-phase high performance liquid chromatography. this antimicrobial peptide was heat-stable and almost completely suppressed the proteolytic activity of trypsin, chymotrypsin and papain, with no hemolytic activity. in addition, potide-g potently inhibited growth of ... | 2006 | 16777063 |
| biofilm formation in an ice cream plant. | the sites of biofilm formation in an ice cream plant were investigated by sampling both the production line and the environment. experiments were carried out twice within a 20-day period. first, stainless steel coupons were fixed to surfaces adjacent to food contact surfaces, the floor drains and the doormat. they were taken for the analysis of biofilm at three different production stages. then, biofilm forming bacteria were enumerated and also presence of listeria monocytogenes was monitored. b ... | 2006 | 16779628 |
| characterization of a new bacteriocin produced from a novel isolated strain of bacillus lentus ng121. | the new bacteriocin is produced from bacillus lentus ng121 isolated from khameera - a traditional fermented food from himachal pradesh, india which has been reported for the first time in the literature to produce bacteriocin and exhibited very high activity units of 20 x 10(5) au (arbitrary units)/ml. this bacteriocin was partially purified and was further characterized to assess its preservation characteristics. it showed strong antimicrobial activity against the most challenging and serious t ... | 2006 | 16779629 |
| [ruptured mesenteric aneurysm from listeria monocytogenes]. | infections due to listeria monocytogenes usually occur in pregnant women, in elderly or immunocompromised patients. we report the case of an immunosuppressed woman who had been hospitalized for a meningoencephalitis due to l. monocytogenes. she was operated on for an abdominal hemorrhagic shock due to a ruptured mycotic aneurysm of the inferior mesenteric artery. arterial aneurysms due to this germ are rare and occur on large arteries. only 17 cases have been previously described in the literatu ... | 2006 | 16780785 |
| adsorption on stainless steel surfaces of biosurfactants produced by gram-negative and gram-positive bacteria: consequence on the bioadhesive behavior of listeria monocytogenes. | the ability of adsorbed biosurfactants (pf and lb) obtained from gram-negative bacterium (pseudomonas fluorescens) or gram-positive bacterium (lactobacillus helveticus) to inhibit adhesion of four listerial strains to stainless steel was investigated. these metallic surfaces were characterized using the following complementary analytical techniques: contact-angle measurements (cam), atomic force microscopy (afm), polarization modulation-infrared reflection-adsorption spectroscopy (pm-irras) and ... | 2006 | 16781848 |
| ultrasound markers of fetal infection, part 2: bacterial, parasitic, and fungal infections. | up to 1% of all pregnancies have clinically overt intra-amniotic bacterial infections, and an even larger percentage of pregnant women may be affected by silent infections. although most pregnant women with overt intra-amniotic bacterial infection have experienced prolonged rupture of membranes (prom), symptomatic and most silent nonviral intra-amniotic infections may occur with intact membranes. the etiology of intra-amniotic infection after prom is almost always polymicrobial and consists of g ... | 2006 | 16783243 |
| acute symptomatic hydrocephalus in listeria monocytogenes meningitis. | listeria monocytogenes meningitis appears to have increased in incidence. although most reported cases of listeriosis involve the central nervous system, brain computed tomography is usually normal. hydrocephalus is a common complication of tuberculous meningitis, which has a high prevalence in taiwan. however, patients with l. monocytogenes meningitis rarely develop the complication of symptomatic hydrocephalus. we report a patient with l. monocytogenes meningitis who presented with persistent ... | 2006 | 16783458 |
| evidence for the opposing roles of different gamma delta t cell subsets in macrophage homeostasis. | to ensure invading pathogens are eliminated with minimal damage to host tissues it is essential that macrophage activation be tightly regulated. previously we demonstrated that a subset of gammadelta t cells (vgamma1(+)) contributes to resolving pathogen-induced immune responses by killing activated macrophages. however, the exaggerated macrophage response seen in infected vgamma1(+) t cell-deficient mice suggests that gammadelta t cells play a broader role in macrophage homeostasis and other su ... | 2006 | 16783854 |
| recovery of heat-injured listeria innocua. | listeria innocua was subjected to thermal inactivation and the extent of heat-injured cells was quantified. cultures were heated in liquid medium for different times, using temperatures in the range of 52.5 to 65.0 degrees c, and plated on tryptic soy agar with 0.6% yeast extract (tsaye) used as non-selective medium and on tsaye plus 5% nacl (tsaye+nacl) and palcam agar with selective supplement (palcam agar) as selective media. the difference observed in counts in non-selective and in selective ... | 2006 | 16784792 |
| self-antigen maintains the innate antibacterial function of self-specific cd8 t cells in vivo. | self-specific cd8 t cells, which are selected by high-affinity interactions with self-ags, develop into a lineage distinct from conventional cd8 t cells. we have previously shown that these self-specific cells acquire phenotypic and functional similarities to cells of the innate immune system including the expression of functional receptors associated with nk cells. in this study, we show that these self-specific cells have the ability to produce large amounts of ifn-gamma in response to infecti ... | 2006 | 16785508 |
| division of labor and cooperation between dendritic cells. | 2006 | 16785884 | |
| a rapid molecular-based assay for direct quantification of viable bacteria in slaughterhouses. | a rapid test for microbial quantification in carcass and environmental swabs that does not require enrichment and provides results in less than 4 h is described here. steps in the assay include the rapid concentration of bacteria on sponge swabs by vacuum filtration followed by real-time pcr detection. the assay has been applied for the detection of coliforms, escherichia coli o157:h7, salmonella spp., and listeria monocytogenes on carcass swabs and environmental samples in a slaughterhouse-proc ... | 2006 | 16786844 |
| chlorine resistance of listeria monocytogenes biofilms and relationship to subtype, cell density, and planktonic cell chlorine resistance. | strains of listeria monocytogenes vary in their ability to produce biofilms. this research determined if cell density, planktonic chlorine resistance, or subtype are associated with the resistance of l. monocytogenes biofilms to chlorine. thirteen strains of l. monocytogenes were selected for this research based on biofilm accumulation on stainless steel and rep-pcr subtyping. these strains were challenged with chlorine to determine the resistance of individual strains of l. monocytogenes. plank ... | 2006 | 16786848 |
| characterization of listeria monocytogenes isolates from 50 small-scale austrian cheese factories. | one hundred eighty-one small-scale cheese factories (annual production < 100,000 kg) were tested for the presence of listeria monocytogenes in cheese and smear samples from 1997 to 2000. in total, 2615 samples were drawn. fifty (27.6%) of 181 enterprises yielded l. monocytogenes. from 14 of the cheese-making facilities, we obtained more than four l. monocytogenes isolates. a total of 182 mostly cheese- and smear-borne l. monocytogenes strains were characterized by serotyping and pulsed-field gel ... | 2006 | 16786849 |
| contamination of cooked peeled shrimp (pandalus borealis) by listeria monocytogenes during processing at two processing plants. | listeria spp. and listeria monocytogenes contamination was evaluated in cooked peeled shrimp (final or semifinal product, 82 samples) and the shrimp-processing environment (two plants, 613 samples) in eight surveys conducted from 1998 through 2001. listeria was detected in 12.5% (78) of the 695 samples (11.2% of the samples were positive for l. monocytogenes), but none of the samples of final product contained listeria. one hundred seventy-two l. monocytogenes isolates were characterized by puls ... | 2006 | 16786850 |
| determination of the growth limits and kinetic behavior of listeria monocytogenes in a sliced cooked cured meat product: validation of the predictive growth model under constant and dynamic temperature storage conditions. | to describe the growth limits of listeria monocytogenes nctc10527 in a sliced vacuum-packaged cooked cured meat product, the binary logistic regression model was used to develop an equation to determine the probability of growth or no growth of l. monocytogenes as a function of temperature (from 0 to 10 degrees c) and water activity (from 0.88 to 0.98). two inoculum concentrations were used (10 and 10(4) cfu g(-1)), and the growth limits for the two inocula were different. the kinetic behavior o ... | 2006 | 16786851 |
| inhibition of listeria innocua in hummus by a combination of nisin and citric acid. | the effect of nisin or citric acid or combinations of these two inhibitors on the inactivation of a cocktail of three listeria innocua strains was investigated in a model brain heart infusion (bhi) broth and hummus (chickpea dip). in bhi broth, citric acid had a limited ability to inhibit l. innocua growth. nisin initially reduced l. innocua concentrations by about 3 log cycles; however, l. innocua reached concentrations similar to those of the control after 5 days at 22 degrees c. in combinatio ... | 2006 | 16786852 |
| effect of cheese water activity and carbohydrate content on the barotolerance of listeria monocytogenes scott a. | high-pressure processing is an appropriate technique for improving the microbiological safety of packaged ready-to-eat foods. the effect of high-pressure treatment on listeria monocytogenes scott a inoculated into fresh hispánico-type cheese and ripe mahón cheese was investigated. a 3.8-log reduction in the counts of l. monocytogenes scott a in fresh cheese was recorded after 3 min at 400 mpa and 12 degrees c, whereas 18 min under the same conditions was required to obtain a 1-log reduction in r ... | 2006 | 16786853 |
| deoxynivalenol and satratoxin g potentiate proinflammatory cytokine and macrophage inhibitory protein 2 induction by listeria and salmonella in the macrophage. | health risks from microbial pathogens and toxins encountered in food and the environment continue to be of worldwide concern. the purpose of this research was to test the hypothesis that trichothecene mycotoxins amplify inflammatory responses to foodborne bacterial pathogens. we assessed the capacity of deoxynivalenol (don) and satratoxin g (sg) to potentiate chemokine and proinflammatory cytokine production in raw 264.7 murine macrophages induced by listeria monocytogenes and salmonella typhimu ... | 2006 | 16786854 |
| pulsed-field gel electrophoresis typing of listeria monocytogenes isolated in two finnish fish farms. | the aim of this study was to find sources of listeria monocytogenes contamination in fish products from a fish farm. the occurrence of l. monocytogenes also was compared in two freshwater fish farms with different types of fishponds. samples collected from chilled rainbow trout (oncorhynchus mykiss) and the slaughterhouse environment did not contain l. monocytogenes, but listeria innocua was found in two samples from the slaughterhouses. ten isolates of l. monocytogenes were discovered in sedime ... | 2006 | 16786871 |
| cold stress tolerance of listeria monocytogenes: a review of molecular adaptive mechanisms and food safety implications. | the foodborne pathogen listeria monocytogenes has many physiological adaptations that enable survival under a wide range of environmental conditions. the microbes overcome various types of stress, including the cold stress associated with low temperatures in food-production and storage environments. cold stress adaptation mechanisms are therefore an important attribute of l. monocytogenes, enabling these food pathogens to survive and proliferate to reach minimal infectious levels on refrigerated ... | 2006 | 16786878 |
| performance evaluation of a low conductive growth medium (lcgm) for growth of healthy and stressed listeria monocytogenes and other common bacterial species. | the performance of a low conductive growth medium (lcgm) (conductivity of <1300 micros) was evaluated for its ability to support growth of food borne bacterial pathogens including listeria monocytogenes and to determine the expression of the two key virulence proteins in l. monocytogenes for possible applications in an impedance-based microfluidic biochip detection platform. growth of listeria was monitored spectrophotometrically and the lag phase, generation time, growth rate and maximum popula ... | 2006 | 16790285 |
| comparison of different live vaccine strategies in vivo for delivery of protein antigen or antigen-encoding dna and mrna by virulence-attenuated listeria monocytogenes. | listeria monocytogenes can be used to deliver protein antigens or dna and mrna encoding such antigens directly into the cytosol of host cells because of its intracellular lifestyle. in this study, we compare the in vivo efficiencies of activation of antigen-specific cd8 and cd4 t cells when the antigen is secreted by l. monocytogenes or when antigen-encoding plasmid dna or mrna is released by self-destructing strains of l. monocytogenes. infection of mice with self-destructing l. monocytogenes c ... | 2006 | 16790768 |
| surface plasmon resonance biosensors for detection of pathogenic microorganisms: strategies to secure food and environmental safety. | this review describes the exploitation of exclusively optical surface plasmon resonance (spr) biosensors for the direct and indirect detection of pathogenic microorganisms in food chains and the environment. direct detection is, in most cases, facilitated by the use of defined monoclonal or polyclonal antibodies raised against (a part of) the target pathogenic microorganisms. the antibodies were immobilized to a solid phase of the sensor to capture the microbe from the sample. alternatively, ant ... | 2006 | 16792081 |
| biosensors for the analysis of food- and waterborne pathogens and their toxins. | biosensors are devices which combine a biochemical recognition element with a physical transducer. there are various types of biosensors, including electrochemical, acoustical, and optical sensors. biosensors are used for medical applications and for environmental testing. although biosensors are not commonly used for food microbial analysis, they have great potential for the detection of microbial pathogens and their toxins in food. they enable fast or real-time detection, portability, and mult ... | 2006 | 16792089 |
| recovery and characterization of a 30.7-kda protein from bacillus licheniformis associated with inhibitory activity against methicillin-resistant staphylococcus aureus, vancomycin-resistant enterococci, and listeria monocytogenes. | of 131 bacterial isolates from seaweed, a culture of bacillus licheniformis produced a novel protein with antibacterial activity against methicillin-resistant staphylococcus aureus, vancomycin-resistant enterococci, and listeria monocytogenes. the antibacterial activity was maximal in cultures prepared in columbia broth containing pieces of synthetic polyurethane sponge and shaken at 210 to 230 rpm. antibacterial activity was not found in cultures grown statically or with different speeds of rot ... | 2006 | 16794953 |
| bioassay-guided purification and identification of antimicrobial components in chinese green tea extract. | the chinese green tea extract was found to strongly inhibit the growth of major food-borne pathogens, escherichia coli o157:h7, salmonella typhimurium dt104, listeria monocytogenes, staphylococcus aureus, and a diarrhoea food-poisoning pathogen bacillus cereus, by 44-100% with the highest activity found against s. aureus and lowest against e. coli o157:h7. a bioassay-guided fractionation technique was used for identifying the principal active component. a simple and efficient reversed-phase high ... | 2006 | 16797571 |