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development of a surface adhesion immunofluorescent technique for the rapid isolation of listeria monocytogenes and listeria innocua from meat.the use of a novel surface adhesion technique to isolate listeria monocytogenes and listeria innocua from an enrichment meat system was developed. minced beef samples inoculated with l. monocytogenes (10 cfu g(-1)) were incubated at 30 degrees c for 14-18 h in a suitable enrichment broth. listeria monocytogenes cells were isolated from the enriched meat sample by surface adhesion onto a polycarbonate membrane which was attached to a glass microscope slide. the listeria cells on the membrane were ...199712452598
two-dimensional polyacrylamide gel electrophoresis analysis of the acid tolerance response in listeria monocytogenes lo28.listeria monocytogenes is capable of withstanding low ph after initial exposure to sublethal acidic conditions, a phenomenon termed the acid tolerance response (b. o'driscoll, c. g. m. gahan, and c. hill, appl. environ. microbiol. 62:1693-1698, 1996). treatment of l. monocytogenes lo28 with chloramphenicol during acid adaptation abrogated the protective effect, suggesting that de novo protein synthesis is required for the acid tolerance response. analysis of protein expression during acid adapta ...199716535645
listeria monocytogenes infection in a prosthetic knee joint in rheumatoid arthritis during methotrexate therapy.a 70-year-old man with rheumatoid arthritis developed listeria monocytogenes septic arthritis in his prosthetic right knee. he initially responded well to ampicillin, but later developed relapse of listeria joint infection. the prosthesis was removed, and arthrodesis was performed. this report suggests that prolonged antimicrobial treatment is necessary to cure this rare cause of septic arthritis of prosthetic joints in immunocompromised patients.199719078179
first trimester listeria monocytogenes septicemia.background: little is known about fetal outcome after listeria monocytogenes septicemia in the first trimester of pregnancy.case: a primigravida with l. monocytogenes septicemia at 9 weeks gestation was treated with amoxicillin. at 40 weeks gestation a healthy female infant was born.conclusion: this case shows that fetal outcome can be normal after appropriate treatment of maternal l. monocytogenes septicemia during embryogenesis.199718476140
[listeria monocytogenes and listeria sp in heat-processed products].presence of listeria monocytogenes in thermoprocessed food which is vacuum packaged, refrigerated stored and eaten uncooked or minimally heated was investigated. thirty samples including sausage, large sausage with ham, spring large sausage, liverwurst and bologna were examined. listeria monocytogenes was isolated and identified according to usda-fsis method for meat products, simultaneously with mcbride agar. seven out of 30 samples were found to contain listeriae. five isolates were identified ...19979424625
[effect of different dairy products on the growth of listeria monocytogenes in selective media].we have studied the influence of the incorporation of milk cream and skim milk on the growth kinetic of listeria monocytogenes in listeria enrichment broth with 15 mg/l or 7.5 mg/l of acriflavine. acriflavine was responsible, at least partially, for delayed growth of listeria monocytogenes in the enrichment broths. a longer lag phase of the growth was produced by the addition of milk cream or skim milk to the enrichment broth containing 7.5 mg/l of acriflavine. however, the maximum population ob ...19979424626
carbon-source regulation of virulence gene expression in listeria monocytogenes.all known virulence genes of listeria monocytogenes are under positive regulation by the transcription factor prfa. previous work employing the l. monocytogenes strain nctc7973 suggested that the disaccharide cellobiose might serve as a specific "signature molecule' which functions to prevent activation of the prfa-controlled regulon in a soil environment. we have examined three other l. monocytogenes strains, 10403s, lo28 and egd, all commonly regarded as wild-type isolates, and find that nctc7 ...19979076743
nucleotide sequence analysis of two virulence-associated genes in listeria monocytogenes serotype 1/2b and comparison with the same genes in other serotypes important in human disease.the nucleotide sequences of the hly and plca genes (encoding listeriolysin, a thiol-activated cytolysin and a non-specific phospholipase c, respectively) were determined for two strains of listeria monocytogenes serotype 1/2b. the deduced amino acid sequences for listeriolysin were identical for the two strains and identical to that of listeriolysin from serotype 4b. the two serotype 1/2b strains differed in one amino acid (histidine vs asparagine) in the deduced amino acid sequence for phosopho ...19979080692
the aerobic growth of aeromonas hydrophila and listeria monocytogenes in broths and on pork.flasks of tryptic soy broth (tsb), unacidified (ph 7.2) or acidified with hcl or lactic acid to ph 6.3 or 5.5, and samples of sterile pork fat or muscle tissue, were inoculated with logarithmic phase cultures of a strain of aeromonas hydrophila or a strain of listeria monocytogenes. the broth cultures were incubated at temperatures between 0 and 25 degrees c, and growth rates were determined from optical density increases. the tissue samples were incubated at temperatures between -2.4 and 25.2 d ...19979081227
simple relationship between acid dissociation constant and minimal ph for microbial growth in laboratory medium.a simple relationship was observed in growth medium, between the dissociation constant (via the pka) of the acid used to control ph and the minimum ph at which salmonellae and escherichia coli initiate growth. from this new relationship, a simple method was proposed to predict the minimum growth ph for a given strain and different acid types. this method, illustrated on listeria monocytogenes, would merely require the knowledge of two minimum ph values, one for a strong acid (e.g. hydrochloric a ...19979081228
structural and functional similarities between the human cytoskeletal protein zyxin and the acta protein of listeria monocytogenes.the intracellular bacterial parasite listeria monocytogenes produces acta protein at its surface to facilitate the localized assembly of actin-filled comets that are required for movement. the organization of actin in listeria comets shows striking similarity to the organization of actin at the plasma membrane of mammalian cells. therefore we examined the possibility that an acta-like protein is present in mammalian cells. by using antibodies directed against acta, we identified zyxin as an acta ...19979296389
stress proteins in listeria monocytogenes.the proteins induced by the different stress conditions in listeria monocytogenes were analyzed by two-dimensional (2-d) electrophoresis with the aid of a computerized 2-d gel analysis system. the stress conditions imposed were ph 4, ph 10, 0.015% sodium, dodecyl sulfate (sds), 0.03% sodium deoxycholate and 4% ethanol. as previously seen for heat shock and cold shock, more than half of the proteins normally synthesized by listeria cells were repressed under these stress conditions. conversely, t ...19979298660
vinculin proteolysis unmasks an acta homolog for actin-based shigella motility.to generate the forces needed for motility, the plasma membranes of nonmuscle cells adopt an activated state that dynamically reorganizes the actin cytoskeleton. by usurping components from focal contacts and the actin cytoskeleton, the intracellular pathogens shigella flexneri and listeria monocytogenes use molecular mimicry to create their own actin-based motors. we raised an antibody (designated fs-1) against the fefpppptde sequence of listeria acta, and this antibody: (a) localized at the tr ...19979298981
mhc class ib-restricted cells contribute to antilisterial immunity: evidence for qa-1b as a key restricting element for listeria-specific ctls.subclinical infection of balb/c mice with the intracellular pathogen listeria monocytogenes results in the development of mhc class ia- and ib-restricted ctls. l. monocytogenes-infected tap-/- bone marrow macrophage targets are not lysed by mhc class ia- or ib-restricted ctls, showing a requirement for transport of peptides into the endoplasmic reticulum for development of the mhc class ib-peptide target. l. monocytogenes-infected b6.tla(a)-derived bone marrow macrophages (kb qa-1a) are not lyse ...19979300701
[pathogenic listeria in the soil and in association with algae: a reversible transition into a nonculturable state].the analysis of the dynamics of the amount of l. monocytogenes in soil extract in association with green algae and in their absence, carried out in parallel by the bacteriological method and in polymerase chain reaction (pcr), revealed the mass transition of l. monocytogenes into the nonculturable state. the proportion of vegetative (bacteriologically detected) forms in the bacterial population rapidly decreased, while its total amount remained unchanged due to the formation of inactive (noncult ...19979304322
in vitro susceptibility of listeria monocytogenes: comparison of the e test with the agar dilution test.in vitro susceptibility testing was performed on 66 strains of listeria monocytogenes. recently obtained clinical isolates from austria, france, norway and switzerland and 17 reference strains from three type culture collections were tested against ampicillin, gentamicin, trimethoprim-sulfamethoxazole, ampicillin-sulbactam, meropenem, and first-, second-, third- and fourth-generation cephalosporins. all isolates were susceptible to ampicillin, gentamicin, and trimethoprim-sulfamethoxazole, ampic ...19979309362
inhibition of listeria monocytogenes growth by veillonella cultured on tartrate medium. 19979310648
adherence to stainless steel by foodborne microorganisms during growth in model food systems.biofilm formation on stainless steel by salmonella typhimurium, listeria monocytogenes, escherichia coli o157:h7, pseudomonas fragi and pseudomonas fluorescens during growth in model food systems was studied. test growth media included tryptic soy broth (tsb), diluted tsb (dtsb), 1% reconstituted skim milk (rsm) and diluted meat juice (dmj). adherent cells were stained with acridine orange and enumerated using epifluorescent microscopy and computerized image analysis. cells were observed on the ...19979310849
distribution and behavior of listeria monocytogenes in three lots of naturally-contaminated vacuum-packed smoked salmon stored at 2 and 10 degrees c.the incidence, the number and the behavior of l. monocytogenes in three lots of naturally-contaminated vacuum-packed sliced smoked salmon, processed in different plants, were investigated during storage at 2 and 10 degrees c. l. monocytogenes was isolated from 20 of the 100 packages stored at 2 degrees c (16 from lot 1, 1 from lot 2 and 3 from lot 3) and from 12 of the 65 packages stored at 10 degrees c (all from lot 1). the levels detected were 15, 20, 290, 1100 and > 1100 cfu/g in 5 packages, ...19979310856
risk factors for contamination of smoked salmon with listeria monocytogenes during processing.forty smoked salmon processing plants were examined for the occurrence of listeria monocytogenes and other listeria spp. in the smoked salmon and the drains. l. monocytogenes was detected in smoked salmon from 13 (33%) and in the drains samples from 25 (63%) of the plants. other listeria spp. were found in smoked salmon samples from 16 (40%) and in the drains of 30 (75%) of the plants. multivariate analyses of data on hygiene, management, production facilities of the plants and bacteriological r ...19979310857
caprine arthritis encephalitis virus dysregulates the expression of cytokines in macrophages.caprine arthritis encephalitis virus (caev) is a lentivirus of goats that leads to chronic mononuclear infiltration of various tissues, in particular, the radiocarpal joints. cells of the monocyte/macrophage lineage are the major host cells of caev in vivo. we have shown that infection of cultured goat macrophages with caev results in an alteration of cytokine expression in vitro. constitutive expression of interleukin 8 (il-8) and monocyte chemoattractant protein 1 (mcp-1) was increased in infe ...19979311828
a novel proline-rich motif present in acta of listeria monocytogenes and cytoskeletal proteins is the ligand for the evh1 domain, a protein module present in the ena/vasp family.the acta protein of the intracellular pathogen listeria monocytogenes induces a dramatic reorganization of the actin-based cytoskeleton. two profilin binding proteins, vasp and mena, are the only cellular proteins known so far to bind directly to acta. this interaction is mediated by a conserved module, the evh1 domain. we identify e/dfppppxd/e, a motif repeated 4-fold within the primary sequence of acta, as the core of the consensus ligand for evh1 domains. this motif is also present and functi ...19979312002
[infection of pleural fluid by listeria monocytogenes]. 19979376411
tcr alpha beta+ cd4- cd8- t cells differentiate extrathymically in an lck-independent manner and participate in early response against listeria monocytogenes infection through interferon-gamma production.t-cell receptor (tcr) alpha beta+ cd4- cd8- (double-negative; dn) t cells appear in the peritoneal cavity at an early stage of intraperitoneal (i.p.) infection with the intracellular pathogen listeria monocytogenes. in the present report, we analysed the developmental pathway and functions of the tcr alpha beta+ dn t cells using the l. monocytogenes infection system. the tcr alpha beta+ dn t cells appeared in the peritoneal cavity after l. monocytogenes i.p. infection in adult-thymectomized leth ...19979378488
the characterization of testicular cell (tc)-specific t-cell clones induced by intratesticular listeria monocytogenes infection: tc-specific t cells with atypical cytokine profile transfer orchitis.a unilateral infection of listeria monocytogenes into the testis of mice induces not only listeria-specific t cells but also autoreactive t cells that can transfer experimental autoimmune orchitis (eao) into naive mice. to investigate the characteristics of the autoreactive t cells, we established six testicular cell (tc)-specific t-cell clones from the spleen of the intratesticularly infected mice. all the clones expressed cd4 and t-cell receptor (tcr) alpha beta, and four of the six clones exp ...19979378489
a synthetic peptide administered with il-12 elicits immunity to listeria monocytogenes.il-12 is a pivotal cytokine signal for the development of th1-type cellular responses that are required for control of intracellular pathogens. we previously demonstrated that coinjection of il-12 with heat-killed listeria monocytogenes, which was not immunogenic when injected alone, elicited intense ag-specific t cell responses that conferred protection against subsequent challenge with listeria. herein we describe the remarkable finding that a nonimmunogenic synthetic peptide corresponding to ...19979378952
intracytoplasmic delivery of listeriolysin o by a vaccinal strain of bacillus anthracis induces cd8-mediated protection against listeria monocytogenes.the facultative intracellular pathogen listeria monocytogenes secretes a 58-kda hemolysin, listeriolysin o (llo), that allows bacteria to access the cytoplasm and to multiply inside infected cells. llo is also a protective ag required for the development of specific immunity. we studied the capacity of a new bacterial vector, derived from an attenuated strain of bacillus anthracis, to deliver in vivo llo and to induce protection against l. monocytogenes infection. the hly gene encoding llo was f ...19979379042
modulation of antigen display by attenuated salmonella typhimurium strains and its impact on protective immunity against listeriosis. 19979382737
models of invasion of enteric and periodontal pathogens into epithelial cells: a comparative analysis.bacterial invasion of epithelial cells is associated with the initiation of infection by many bacteria. to carry out this action, bacteria have developed remarkable processes and mechanisms that co-opt host cell function and stimulate their own uptake and adaptation to the environment of the host cell. two general types of invasion processes have been observed. in one type, the pathogens (e.g., salmonella and yersinia spp.) remain in the vacuole in which they are internalized and replicate withi ...19979391752
the rpon (sigma54) gene from listeria monocytogenes is involved in resistance to mesentericin y105, an antibacterial peptide from leuconostoc mesenteroides.to gain insight into the mode of action of mesentericin y105, a bacteriocin bactericidal agent against listeria monocytogenes, we undertook to identify the listerial factors mediating this susceptibility by using a genetic approach. transposon mutants resistant to the bacteriocin were obtained. one of them corresponded to a transposon insertion in a gene (rpon) encoding a putative protein (447 amino acids) with strong homologies to alternative transcriptional sigma54 factors, including that of b ...19979393729
transient control of interleukin-4-producing natural killer t cells in the livers of listeria monocytogenes-infected mice by interleukin-12.unconstrained development of gamma interferon (ifn-gamma)-secreting natural killer (nk) cells and t helper (th) 1 cells is central to protection against listeria monocytogenes. in contrast, interleukin 4 (il-4) is considered harmful. il-12 produced by infected macrophages promotes, and il-4 interferes with, protective antilisterial immunity. the liver nk t lymphocytes, which are a potent source of il-4, are downregulated at an intermediate stage of listeriosis. here we demonstrate that endogenou ...19979393789
internalin b promotes the replication of listeria monocytogenes in mouse hepatocytes.the uptake of listeria monocytogenes by a variety of cell types in vitro is facilitated by the protein products of the inlab (internalin) operon expressed by the organism. in the case of mouse hepatocytes, the extent to which inlab expression influenced the uptake of listeria in vitro was markedly dependent upon the ratio of bacteria to cells. at a ratio of 100:1, greater than 40-fold fewer transposon-induced inl4b mutant listeriae entered hepatocytes compared to the isogenic wild-type control; ...19979393807
comparison of inducible nitric oxide synthase expression in the brains of listeria monocytogenes-infected cattle, sheep, and goats and in macrophages stimulated in vitro.the expression of inducible nitric oxide synthase (inos) was studied in the brains of cattle, sheep, and goat that succumbed to a natural infection with listeria monocytogenes. the lesions in infected brains are characterized by microabscesses, perivascular cuffs, gliosis, glial nodules, and large areas of malacia. using immunocytochemistry, we detected bacteria in microabscesses, particularly in sheep and goats, and in areas without signs of inflammation, but not in perivascular infiltrates. in ...19979393827
internalin of listeria monocytogenes with an intact leucine-rich repeat region is sufficient to promote internalization.listeria monocytogenes can use two different surface proteins, internalin (inla) and inlb, to invade mammalian cells. the exact role of these invasiveness factors in vivo remains to be determined. in cultured cells, inla is necessary to promote listeria entry into human epithelial cells, such as caco-2 cells, whereas inlb is necessary to promote listeria internalization in several other cell types, including hepatocytes, fibroblasts, and epithelioid cells, such as vero, hela, cho, or hep-2 cells ...19979393831
a nonamer peptide derived from listeria monocytogenes metalloprotease is presented to cytolytic t lymphocytes.listeria monocytogenes is an intracellular bacterium that secretes proteins into the cytosol of infected macrophages. major histocompatibility complex (mhc) class i molecules bind peptides that are generated by the degradation of bacterial proteins and present them to cytolytic t lymphocytes (ctl). in this study we have investigated ctl responses in l. monocytogenes-immunized mice to peptides that (i) derive from the l. monocytogenes proteins phosphatidylinositol-specific phospholipase c, lecith ...19979393833
bacterial meningitis in the united states in 1995. active surveillance team.before the introduction of the conjugate vaccines, haemophilus influenzae type b was the major cause of bacterial meningitis in the united states, and meningitis was primarily a disease of infants and young children. we describe the epidemiologic features of bacterial meningitis five years after the h. influenzae type b conjugate vaccines were licensed for routine immunization of infants.19979395430
short-chain phosphatidylinositol conformation and its relevance to phosphatidylinositol-specific phospholipase c.the solution conformation of chiral diheptanoylphosphatidylinositol (d- and l-inositol isomers) has been characterized by nmr spectroscopy. a positive noe between the inositol c2 proton and an sn-3 glycerol ch2 proton has been observed in the d- but not in the l-inositol isomer of diheptanoylphosphatidylinositol (pi). computer modeling using quanta constrained by this noe and ring coupling constants suggests that the inositol ring is nearly parallel to the chain packing direction, leaving the ph ...19979398326
innate resistance to listeria monocytogenes in tumor-bearing mice.we have previously described the isolation, cloning, and characterization of a tumorigenic murine fibrosarcoma, designated jbs. growth of jbs tumors in syngeneic mice initiates an anti-tumor immune response that initially manifests as progressive splenic hyperplasia and an increased proliferative ability in cultured splenocytes. in animals with tumors progressing beyond the 2 cm stage there is a reduction in spleen size and a gradual decrease in splenocyte proliferative abilities, leading to ane ...19979400813
effector molecules in expression of the antimicrobial activity of macrophages against mycobacterium avium complex: roles of reactive nitrogen intermediates, reactive oxygen intermediates, and free fatty acids.we studied microbicidal activities of reactive nitrogen intermediates (rni), free fatty acids (ffa), and reactive oxygen intermediates (roi) against mycobacterium avium complex (mac) and the mode of macrophage (mphi) production of these effectors. (1) intracellular growth of mac in murine peritoneal mphis was accelerated by scavengers for roi or rni and inhibitors of nitric oxide synthase or phospholipase a2, indicating roles of roi, rni, and ffa in mphi anti-mac functions. (2) acidified nano2-d ...19979400821
listeriolysin o potentiates immunotoxin and bleomycin cytotoxicity.antitumor immunotoxins were formed by covalently attaching the ribosome-inactivating protein ricin a chain (ra) to the antitumor antibodies br96 and l6. in vitro cytotoxicity assays established that br96-ra was cytotoxic to h2987 human lung adenocarcinoma cells (ic50 = 6 nm), while l6-ra exhibited very low levels of cytotoxic activity (18% cell kill at 67 nm). the virulence factor from the intracellular pathogen listeria monocytogenes, listeriolysin o (llo), was able to potentiate the cytotoxici ...19979404648
penetration of listeria monocytogenes in mice infected by the oral route.in this study, it is suggested that the peyer's patches are the most important point of entry of listeria monocytogenes in the host after subclinical infection by the oral route. microbiological, histopathological and ultrastructural evidence of infection was obtained in mice inoculated with a sublethal dose of 10(9) cfu. no mortality was observed. l. monocytogenes was isolated from the mesenteric lymph nodes from 6 hours post infection (hpi) through day 7 p.i. and from the liver and spleen from ...19979405203
pseudo-outbreak of listeriosis elucidated by pulsed-field gel electrophoresis.listeria monocytogenes was isolated from three patients hospitalized in two departments of the same hospital over a two-week period. a nosocomial outbreak of listeriosis was suspected. patients presented with tenosynovitis, central venous catheter infection, and bacteremia. the first patient had a community-acquired infection, the second a nosocomial infection, and the source of the third patient's illness was uncertain. epidemiological investigations failed to identify a common source of contam ...19979405949
a mutant of listeria monocytogenes lo28 unable to induce an acid tolerance response displays diminished virulence in a murine model.exposing listeria monocytogenes lo28 to sublethal ph induces protection against normally lethal ph conditions, a phenomenon known as the acid tolerance response. we identified a mutant, l. monocytogenes atr1, which is incapable of inducing such tolerance, either against low ph or against any other stress tested. the virulence of this mutant was considerably decreased, suggesting that the acid tolerance response contributes to in vivo survival of l. monocytogenes.19979406415
[meropenem: microbiologic perspective].meropenem is a beta-lactamic carbapenem derived from thienamycin and is structurally characterized by the presence of a beta-methyl group in position c1 which confers stability to the molecule versus renal dehydropeptidase 1 (dhp-1), thereby making the coadministration of an enzyme inhibitor unnecessary. its esterochemical configuration of the lateral chain in c2 (dimethyl carbomoilpyrrolidenethium) increases the activity versus gram negative bacteria (enterobacteria and pseudomonas) and moreove ...19979410064
oral somatic transgene vaccination using attenuated s. typhimurium.an attenuated strain of s. typhimurium has been used as a vehicle for oral genetic immunization. eukaryotic expression vectors containing truncated genes of acta and listeriolysin--two virulence factors of listeria monocytogenes--have been used to transform s. typhimurium aroa. multiple or even single oral immunizations with such transformants induced excellent cellular and humoral responses. in addition, protective immunity was induced with listeriolysin transformants. the quality of the respon ...19979413986
macrophages activated by listeria monocytogenes induce organ-specific autoimmunity.we have previously reported an experimental autoimmune model induced by the local infection of listeria monocytogenes. the unilateral inoculation of virulent listeria into a testis of a normal mouse induced a delayed-type hypersensitivity response against testicular antigen and caused autoimmune orchitis in the contralateral testis. the orchitis was transferred to naive mice by t cells from the intratesticularly infected mice. in this paper, we demonstrated that avirulent listeria, which lacks t ...19979415037
the use of ethidium bromide to assess a novel injury/recovery phenomenon in listeria monocytogenes in inhibitory nacl conditions.an injury and recovery phenomenon was observed in listeria monocytogenes inoculated into a medium containing 2.2 mmol l -1 nacl, a concentration that was inhibitory to growth. the apparent loss then recovery of viability, as determined by plate counts, was compared with the uptake of ethidium bromide by the cells and found to be inversely related. injury was caused not only by the initial osmotic up-shock but also by the subsequent down-shock involved in the spread plate protocol.19979418074
involvement of map-kinases and -phosphatases in uptake and intracellular replication of listeria monocytogenes in j774 macrophage cells.in this study we show that protein tyrosine kinases and also protein tyrosine phosphatases are involved in the uptake of listeria monocytogenes by j774 macrophages to a different extent than in the uptake of inert latex beads. in addition, protein tyrosine kinases are necessary for the intracellular growth and survival of l. monocytogenes. the expression of the map kinase phosphatase mkp-1, a protein tyrosine phosphatase, is induced upon infection, and phagocytosis of l. monocytogenes by j774 ce ...19979418248
listeria monocytogenes-infected human umbilical vein endothelial cells: internalin-independent invasion, intracellular growth, movement, and host cell responses.the interaction of listeria monocytogenes with human umbilical vein endothelial cells was studied. we show that l. monocytogenes invades human umbilical vein endothelial cells independently of internalin a, internalin b, internalin c, and acta. l. monocytogenes replicates efficiently inside the cells and moves intracellularly by the induction of actin polymerization. we further show that l. monocytogenes-infection of human umbilical vein endothelial cells induces interleukin-6 and interleukin-8 ...19979418251
comparison of antibody-direct epifluorescent filter technique with the most probable number procedure for rapid enumeration of listeria in fresh vegetables.the antibody-direct epifluorescent filter (ab-deft) technique was evaluated as a rapid alternative to the most probable number (mpn) method for enumeration of artificially inoculated listeria monocytogenes in ready-to-eat packaged salads and other fresh vegetables. ab-deft was performed by homogenization of food in mesh-lined stomacher bags, followed by prefiltration of homogenate through a 5 microns pore nylon filter, and passage of filtrate through a 0.4 micron pore black polycarbonate filter ...19979419860
protection against murine listeriosis by an attenuated recombinant salmonella typhimurium vaccine strain that secretes the naturally somatic antigen superoxide dismutase.a recombinant (r)-salmonella typhimurium aroa vaccine strain was constructed which secretes the naturally somatic protein of listeria monocytogenes, superoxide dismutase (sod), by the hlyb/hlyd/tolc export machinery. vaccine efficacy of the sod-bearing carrier strain was compared with that of the p60-secreting construct, s. typhimurium p60s (j. hess, i. gentschev, d. miko, m. welzel, c. ladel, w. goebel, and s. h. e. kaufmann, proc. natl. acad. sci. usa 93:1458-1463, 1996). vaccination of mice w ...19979119463
evidence that prfa, the pleiotropic activator of virulence genes in listeria monocytogenes, can be present but inactive.all virulence genes of listeria monocytogenes identified to date are positively regulated by prfa, a transcriptional activator belonging to the crp-fnr family. low temperature and cellobiose are two environmental signals known to repress expression of virulence genes in l. monocytogenes. in the present work, we analyzed the effect of temperature and cellobiose on the expression of the prfa protein. at low temperature, prfa was undetected, although prfa monocistronic transcripts are present. in c ...19979119495
molecular diagnostics for dairy-borne pathogens.advances in diagnostic assays based on nucleic acids will revolutionize the ability of the industry to maintain the safety of dairy foods. two complementary assay formats are explored, one of which permits the rapid detection of bacterial pathogens and the other the identification of reservoirs of these pathogens. the first format is an assay based on the polymerase chain reaction that employs homogeneous detection (taqman polymerase chain reaction detection; perkin elmer, applied biosystems div ...19979120093
immunodominant and subdominant ctl responses to listeria monocytogenes infection.protective immunity to infection by intracellular pathogens begins with expansion of ag-specific, effector t lymphocytes and is followed by persistence of pathogen-specific memory t cells. infection by listeria monocytogenes, an intracellular bacterium, induces cytolytic t lymphocytes that mediate systemic sterilization and long term immunity. in cells infected with l. monocytogenes, h2-kd class i molecules present three nonamer peptides, listeriolysin (llo) 91-99, p60 217-225, and p60 449-457, ...19979120295
crucial role of interferon consensus sequence binding protein, but neither of interferon regulatory factor 1 nor of nitric oxide synthesis for protection against murine listeriosis.listeria monocytogenes is widely used as a model to study immune responses against intracellular bacteria. it has been shown that neutrophils and macrophages play an important role to restrict bacterial replication in the early phase of primary infection in mice, and that the cytokines interferon-gamma (ifn-gamma) and tumor necrosis factor-alpha (tnf-alpha) are essential for protection. however, the involved signaling pathways and effector mechanisms are still poorly understood. this study inves ...19979120398
membrane permeabilization by listeria monocytogenes phosphatidylinositol-specific phospholipase c is independent of phospholipid hydrolysis and cooperative with listeriolysin o. 19979122270
animal and human listeriosis: a shared problem? 19979125351
a review of listeria monocytogenes and listeriosis.following the initial isolation and description in 1926 listeria monocytogenes has been shown to be of world-wide prevalence and is associated with serious disease in a wide variety of animals, including man. our knowledge of this bacterial pathogen and the various forms of listeriosis that it causes has until recently been extremely limited, but recent advances in taxonomy, isolation methods, bacterial typing, molecular biology and cell biology have extended our knowledge. it is an exquisitely ...19979125353
identification of four new members of the internalin multigene family of listeria monocytogenes egd.listeria monocytogenes is a bacterial pathogen that is able to invade nonphagocytic cells. two surface proteins, internalin, the inla gene product, and inlb, play important roles in the entry into cultured mammalian cells. these proteins also have extensive sequence similarities. previously, southern hybridization predicted the existence of an internalin multigene family. recently, inlc, a secreted protein of 30 kda homologous to inla and inlb, was identified. in this work, we identified and cha ...19979125538
cd95 (fas) may control the expansion of activated t cells after elimination of bacteria in murine listeriosis.cd95 (fas) is known to mediate activation-induced t-cell death by apoptosis. to understand the role of cd95 during the course of bacterial infection, we examined the kinetics of alphabeta and gammadelta t cells in the peritoneal cavities and livers of 5-week-old cd95-defective mrl/lpr mice after an intraperitoneal infection with listeria monocytogenes. the number of bacteria in the spleen decreased to an undetectable level by day 10 after infection with 7 x 10(3) listeria cells similar to the nu ...19979125576
neutrophils and tumour necrosis factor-alpha are important for controlling early gastrointestinal stages of experimental murine listeriosis.the present study examined the need for neutrophils and tumour necrosis factor-alpha (tnf alpha) for early defence against gut infection with the enteroinvasive, facultative intracellular bacterial pathogen, listeria monocytogenes. mice were treated with a neutrophil-depleting monoclonal antibody (mab) or a mab directed against tnf alpha, and the consequences of these treatments on the course of orally initiated infection with the pathogen were monitored. by day 3, orally initiated l. monocytoge ...19979126825
enhanced intracellular dissociation of major histocompatibility complex class i-associated peptides: a mechanism for optimizing the spectrum of cell surface-presented cytotoxic t lymphocyte epitopes.association of antigenic peptides with newly synthesized major histocompatibility complex (mhc) class i molecules occurs in the endoplasmic reticulum and is a critical early step for the initiation of cytotoxic t lymphocyte (ctl)-mediated immune defenses. pathogen-derived peptides compete with a plethora of endogenous peptides for mhc class i grooves. we find that two h2-k(d)-restricted peptides, which derive from the listeria monocytogenes p60 antigen, accumulate in infected cells with differen ...19979126921
emerging issues in microbiological food safety.many microorganisms previously unrecognized as food-borne or harmful are emerging as human pathogens transmitted by food. this is a result of recent acquisition of key virulence factors, detection by newly developed isolation procedures, or astute detective-like laboratory skills of microbiologists. six microbial pathogens, including shiga toxin-producing escherichia coli, listeria monocytogenes, arcobacter butzleri, helicobacter pylori, cryptosporidium parvum, and cyclospora, have become recogn ...19979240928
typing of austrian listeria monocytogenes isolates by automated laser fluorescence analysis of randomly amplified polymorphic dna.we used automated laser fluorescence analysis of randomly amplified polymorphic dna (rapd-alfa) to study the epidemiology of listeriosis in western austria. there were no discrepancies between rapd-alfa patterns and serotypes found in 18 food isolates and 18 clinical isolates. the results of our study suggest that the food isolates typed were not at the origin of the human cases in western austria. using rapd-alfa, it was possible to link 9 out of 16 "sporadic" listeria infections (mother-child ...19979241798
cell wall-deficient forms (l-forms) of listeria monocytogenes in experimentally infected rats.experimental infections were induced with different bacterial forms of listeria monocytogenes: parental (s-forms), protoplastic (l-forms) and combined inoculum of both forms by i.p. injection of rats. the parental bacterial forms (s-forms) were isolated up to 7 days after challenge from the peritoneal cavity and the liver, while the l-forms were isolated up to 60 days from the peritoneal cavity. continuous adhesion of l-forms on the peritoneal macrophage surface was found by scanning-electron mi ...19979241800
assurance polyclonal enzyme immunoassay for detection of listeria monocytogenes and related listeria species in selected foods: collaborative study.six foods representing a variety of food products were analyzed by the assurance listeria polyclonal enzyme immunoassay (eia) and by either the bacteriological analytical manual or the u.s. department of agriculture culture method for detecting listeria monocytogenes and related listeria species. samples of each food type, at each inoculation level, were analyzed simultaneously by both methods. a total of 19 laboratories representing federal government agencies and private industry in the united ...19979241842
visual immunoprecipitate assay (vip) for listeria monocytogenes and related listeria species detection in selected foods: collaborative study.six foods representing a variety of food products were analyzed by the visual immunoprecipitate assay (vip) and either the bacteriological analytical manual (bam) or the u.s. department of agriculture culture methods for detection of listeria monocytogenes and related listeria spp. samples of each food type at each inoculation level were simultaneously analyzed by both methods. a total of 23 laboratories representing federal agencies and private industry in the united states and canada participa ...19979241843
predictive microbiology of dairy products: influence of biological factors affecting growth of listeria monocytogenes.the growth potential of listeria monocytogenes was evaluated at low temperature in sterilized milk and raw dairy products. sterilized and raw milk were inoculated with different strains of l. monocytogenes in 2 physiological states and at various contamination levels. raw cheese was naturally contaminated with listeria spp. the results suggest that some biological factors influence the growth capacity of l monocytogenes in dairy products. significant strain effect was observed at low temperature ...19979241852
a case of congenital listeria septicemia associated with high levels of inflammatory cytokines.a case of congenital listeria septicemia is reported. a 2256 g male infant suffering from respiratory and circulatory failure with shock-like symptoms and high levels of inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1 beta, -6, and -8), was admitted to the morioka red cross hospital. listeria monocytogenes was cultured from cord blood, contents from the external ear canal, rectum and stomach. the infant was treated with surfactant replacement as well as conventional therapy. t ...19979241908
sporadic case of listeriosis associated with the consumption of a listeria monocytogenes-contaminated 'camembert' cheese.listeria monocytogenes is an intracellular gram-positive organism responsible for severe infections in both humans and animals. whereas the food-borne transmission of listeriosis was demonstrated in several outbreaks, most cases of listeriosis occur sporadically and are rarely linked with consumption of contaminated foods. in this paper a case of septicaemia with l. monocytogenes in a 73-year-old immunocompromised man is described. evidence for the association of this case of listeriosis with th ...19979354360
the effect of interleukin-10 on meningeal inflammation in experimental bacterial meningitis.interleukin-10 (il-10) is a cytokine with antiinflammatory effects. in a rabbit model of meningitis, il-10 was given intracisternally or intravenously to evaluate the impact on inflammation induced by lipooligosaccharide (los), haemophilus influenzae type b (hib), or listeria monocytogenes. intracisternal il-10 in concentrations >1 microg significantly reduced tumor necrosis factor-alpha (tnf-alpha) and lactate values in cerebrospinal fluid (csf). intravenous il-10 (1 mg/kg) in two doses after i ...19979359724
identification of listeria monocytogenes by colony hybridization test using the virulence-associated hly and inla genes as probes.we developed a method of identification of listeria monocytogenes based on colony hybridization with nonradioactively labeled dna probes, represented by the hly and inla virulence-associated genes. the procedure described in this paper results simple, rapid, specific and reproducible. since it can be performed in a short time, the above technique can be applied to detect l. monocytogenes from different source and constitutes a noteworthy and alternative tool to identify this gram-positive pathog ...19979360328
manure and microbes: public and animal health problem?most environmental concerns about waste management either have focused on the effects of nutrients, especially n and p, on water quality or have emphasized odor problems and air quality. microbes from manure are often low on the priority list for control and remediation, despite the fact that several outbreaks of gastroenteritis have been traced to livestock operations. the pathogens discussed in this paper include protozoans (cryptosporidium parvum, giardia spp.), bacteria (listeria monocytogen ...19979361239
clinafloxacin (cl 960) is superior to standard therapeutics in the treatment of murine listeriosis and salmonellosis.clinafloxacin is a novel fluoroquinolone with a broad spectrum of antibacterial activity against both gramnegative and grampositive bacteria. in this work, the activity against the facultatively intracellular bacteria listeria monocytogenes and salmonella typhimurium was examined in vitro, in tissue culture and in animal models of infection. all strains of l. monocytogenes and s. enterica were highly susceptible against clinafloxacin, with minimal inhibitory concentrations (mics) that were consi ...19979361386
biochemical and genetic characterization of enterocin p, a novel sec-dependent bacteriocin from enterococcus faecium p13 with a broad antimicrobial spectrum.enterocin p is a new bacteriocin produced by enterococcus faecium p13 isolated from a spanish dry-fermented sausage. enterocin p inhibited most of tested spoilage and food-borne gram-positive pathogenic bacteria, such as listeria monocytogenes, staphylococcus aureus, clostridium perfringens, and clostridium botulinum. enterocin p is produced during growth in mrs broth from 16 to 45 degrees c; it is heat resistant (60 min at 100 degrees c; 15 min at 121 degrees c) and can withstand exposure to ph ...19979361419
sensitive detection of viable listeria monocytogenes by reverse transcription-pcr.detection of pathogens in contaminated food products by pcr can result in false-positive data due to the amplification of dna from nonviable cells. a new method based on reverse transcription-pcr (rt-pcr) amplification of mrna for the specific detection of viable listeria monocytogenes was developed. the expression of three l. monocytogenes genes, iap, hly, and prfa, was examined to determine a suitable target for amplification of rt-pcr. total rna from l. monocytogenes was isolated, and followi ...19979361430
defects in macrophage recruitment and host defense in mice lacking the ccr2 chemokine receptor.chemokines are a structurally related family of cytokines that are important for leukocyte trafficking. the c-c chemokine monocyte chemoattractant protein-1 (mcp-1) is a potent monocyte activator in vitro and has been associated with monocytic infiltration in several inflammatory diseases. one c-c chemokine receptor, ccr2, has been identified that mediates in vitro responses to mcp-1 and its close structural homologues. ccr2 has also recently been demonstrated to be a fusion cofactor for several ...19979362535
in vivo properties of monocyte chemoattractant protein-1.monocyte chemoattractant protein-1 (mcp-1) attracts monocytes, memory t lymphocytes, and natural killer (nk) cells in vitro. its expression has been documented in disorders characterized by mononuclear cell infiltrates, suggesting that it may contribute to the inflammatory component of such diseases as atherosclerosis, multiple sclerosis, or rheumatoid arthritis. to prove a causal association, the in vivo properties of mcp-1 must be understood. several lines of transgenic mice have been construc ...19979365111
produce handling and processing practices.in the past decade, outbreaks of human illness associated with the consumption of raw vegetables and fruits (or unpasteurized products produced from them) have increased in the united states. changes in agronomic, harvesting, distribution, processing, and consumption patterns and practices have undoubtedly contributed to this increase. pathogens such as listeria monocytogenes, clostridium botulinum, and bacillus cereus are naturally present in some soil, and their presence on fresh produce is no ...19979366597
historical overview of key issues in food safety.foodborne transmission of pathogenic and toxigenic microorganisms has been a recognized hazard for decades. even half a century ago we knew about the dangers of botulism from underprocessed canned foods; staphylococcal poisoning from unrefrigerated cream-filled pastries, sliced ham, meat, and poultry salads; and salmonellosis from infected animal products. despite new protective measures, changes in preservation techniques and failure to follow recognized procedures have created new dangers. mor ...19979366600
crystal structure of the phosphatidylinositol-specific phospholipase c from the human pathogen listeria monocytogenes.the x-ray crystal structure of the phosphatidylinositol-specific phospholipase c (pi-plc) from the human pathogen listeria monocytogenes has been determined both in free form at 2.0 a resolution, and in complex with the competitive inhibitor myo-inositol at 2.6 a resolution. the structure was solved by a combination of molecular replacement using the structure of bacillus cereus pi-plc and single isomorphous replacement. the enzyme consists of a single (beta alpha)8-barrel domain with the active ...19979367761
normal macrophage functions, but impaired induction of gamma delta t cells, at the site of bacterial infection in cd45 exon 6-deficient mice.we investigated the protective functions of macrophages and gamma delta t cells in adult cd45 exon 6-deficient (cd45 -/-) mice against an intraperitoneal (i.p.) infection with listeria monocytogenes. gamma delta t cells are preferentially localized in the spleen, liver, and intraperitoneal cavity of the adult cd45-/- mice. increased numbers of gamma delta t cells were observed after i.p. infection with l. monocytogenes in the peritoneal cavity of c57bl/6 (cd45 +/+) mice but not in cd45 -/- mice. ...19979368609
betaine and l-carnitine transport by listeria monocytogenes scott a in response to osmotic signals.the naturally occurring compatible solutes betaine and l-carnitine allow the food-borne pathogen listeria monocytogenes to adjust to environments of high osmotic strength. previously, it was demonstrated that l. monocytogenes possesses an atp-dependent l-carnitine transporter (a. verheul, f. m. rombouts, r. r. beumer, and t. abee, j. bacteriol. 177:3205-3212, 1995). the present study reveals that betaine and l-carnitine are taken up by separate highly specific transport systems and support a sec ...19979371443
glucose-1-phosphate utilization by listeria monocytogenes is prfa dependent and coordinately expressed with virulence factors.virulence genes of the facultative intracellular pathogen listeria monocytogenes are coordinately regulated by the activator protein prfa, encoded by prfa, a member of the cyclic amp receptor protein family of bacterial transcription factors. we found that prfa* mutants that constitutively overexpress the virulence regulon due to a gly145ser substitution in prfa (m.-t. ripio, g. domínguez-bernal, m. lara, m. suárez, and j.-a. vázquez-boland, j. bacteriol. 179:1533-1540, 1997) rapidly utilized gl ...19979371468
cd8alphaalpha t cells in lesions of listeria monocytogenes-infected beta2m-deficient mice.the beta2-microglobulin (beta2m)-deficient mutant mice lack alphabeta tcr cd8alphabeta t cells. we found markedly impaired granuloma formation in listeria monocytogenes-infected beta2m-/- mice. abundant cd8alphaalpha t cells were identified in loosely structured infiltrative liver lesions. microfluorescence analysis disclosed that these cd8alphaalpha t cells expressed mostly the gammadelta tcr. cd8alphaalpha t cells were also found in the spleen of listeria-infected beta2m-/- mice. these data pr ...19979245621
conjugative transfer of tet(s) between strains of enterococcus faecalis is associated with the exchange of large fragments of chromosomal dna.the tetracycline resistance determinant tet(s) was first detected in antibiotic multiresistant listeria monocytogenes bm4210 and subsequently in strains of enterococcus faecalis. transfer of tet(s) from clinical isolate e. faecalis bm4242 to e. faecalis strains jh2-2 and og1rf was found to require the presence in the donor strain of the 55 kb conjugative plasmid pip825. comparison of restriction endonuclease generated maps of the donor, the two recipients, and of four transconjugants indicated t ...19979245804
physiological and biochemical studies on psychrotolerance in listeria monocytogenes.studies were undertaken to explain the ability of listeria monocytogenes to grow at low temperatures in a chemostat. it was found that when grown in continuous culture at a dilution rate of 0.02 h-1 l. monocytogenes had a lower proportion of anteiso-17:0, and a higher proportion of anteiso-15:0, and smaller chain fatty acids when grown at 10 degrees c compared to 30 degrees c. a previously unreported glycolipid was only seen after growth at low temperature. growth temperature had no effect on th ...19979246768
microbiological composition of raw milk from selected farms in the camembert region of normandy.raw milk from 27 farms was sampled over 6 months for listerias, salmonellas, yersinia enterocolitica and campylobacters. total bacterial counts and somatic cell counts were measured. lactococci, lactobacilli, dextran-producing leuconostocs, brevibacterium linens, yeasts and moulds, staphylococcus aureus and other micrococcaceae, pseudomonas, coliforms, escherichia coli, enterococci, clostridium perfringens and spores of anaerobic lactate-fermenting bacteria were also counted. pseudomonas (2000 c ...19979246770
the effect of temperature, ph and medium in a surface adhesion immunofluorescent technique for detection of listeria monocytogenes.a rapid surface adhesion-based immunofluorescence technique was used to detect listeria monocytogenes from inoculated culture systems. the effect of culture type (pure, mixed and meat), ph (7.00, 6.40, 4.76 and 3.13), acids (citric and hcl) and temperature (25 degrees, 30 degrees and 37 degrees c) on the adhesion of listeria to the polycarbonate membrane used in this technique was determined. it was found that ph had a significant effect (p < 0.05) with higher numbers of listeria adhering at low ...19979246776
antimicrobial activity of food-related penicillium sp. against pathogenic bacteria in laboratory media and a cheese model system.food-related penicillium species (n = 34) and geotrichum candidum (n = 11) grown on czapek dox and brie agar were tested for their ability to suppress growth of pathogenic bacteria. ten out of 13 p. camemberti showed antagonistic activity while the other species did not interact significantly with the bacterial growth. the order of inhibition was: gram-negative bacteria and bacillus cereus > listeria monocytogenes, lactococcus sp. > micrococcus sp. whereas lactobacillus sp., staphylococcus aureu ...19979246777
antigen-specific t cell receptor antagonism by antigen-presenting cells treated with the hemolysin of listeria monocytogenes: a novel type of immune escape.we have examined the influence of listeriolysin o (llo), the hemolysin secreted by the pathogenic bacterium listeria monocytogenes, on major histocompatibility complex class ii-dependent t cell activation. stimulation of t cells by native antigens but not by peptides is inhibited upon pretreatment of antigen-presenting cells (apc) with llo. experiments presented here reveal that this inhibition is not due to a lack in processing of antigen by apc but is the result of an irreversible inactivation ...19979247580
the effect of high hydrostatic pressure on the activity of intracellular enzymes of listeria monocytogenes.the effect of high hydrostatic pressure (100-550 mpa, 15 min, ambient temperature) on the activity of 13 metabolic enzymes produced by all three strains of listeria monocytogenes (nctc 11994, a poultry isolate and scott a) was examined using gel electrophoresis. the enzymes assayed exhibited a wide variation in barotolerance. the pressure resistance of each particular enzyme was not dependent on the strain from which it was derived. this would seem to indicate that these enzymes were not a deter ...19979248081
an outbreak of listeriosis in a breeding colony of chinchillas. 19979249176
a gerbil model for rhombencephalitis due to listeria monocytogenes.rhombencephalitis due to listeria monocytogenes is a frequent complication of human listeriosis, inducing a high mortality and severe neurological sequelae despite antibiotic therapy. however, there is no animal model which consistently reproduces clinical rhombencephalitis. here, we present a model of listeria rhombencephalitis in gerbils. animals were inoculated in the middle ears with a low infective dose of l. monocytogenes, thus creating prolonged otitis media with persistent bacteremia. ge ...19979250779
evaluation of luciferase reporter bacteriophage a511::luxab for detection of listeria monocytogenes in contaminated foods.a511::luxab is a recombinant derivative of a broad-host-range bacteriophage specific for the genus listeria, transducing bacterial bioluminescence into infected cells. in this study, we have evaluated its use for rapid and easy testing of contaminated foods and environmental samples for the presence of viable listeria cells, in comparison to the standard plating procedure. with a short preenrichment step of 20 h, the system was capable of detecting very low initial contamination rates in several ...19979251182
host-mediated modification of sau3ai restriction in listeria monocytogenes: prevalence in epidemic-associated strains.most major food-related outbreaks of listeriosis have been traced to a cluster of genetically related strains of serovar 4b (epidemic clone). in spite of numerous searches, distinct bacteriologic or virulence-related features unique to these strains have eluded identification, although a restriction fragment length polymorphism (rflp) characteristic of the epidemic clone has previously been described (w. zheng and s. kathariou, appl. environ. microbiol. 61:4310-4314, 1995). we found that dnas fr ...19979251194
effects of several factors on the heat-shock-induced thermotolerance of listeria monocytogenes.the influence of the temperature at which listeria monocytogenes had been grown (4 or 37 degrees c) on the response to heat shocks of different durations at different temperatures was investigated. for cells grown at 4 degrees c, the effect of storage, prior to and after heat shock, on the induced thermotolerance was also studied. death kinetics of heat-shocked cells is also discussed. for l. monocytogenes grown at 37 degrees c, the greatest response to heat shock was a fourfold increase in ther ...19979251209
fatal listeria meningitis, endocarditis and pericarditis in a patient with haemochromatosis.a 65-year-old man with primary haemochromatosis was admitted because of fever and confusion. he was found to have bacteraemia and meningitis due to listeria monocytogenes. treatment with ampicillin plus tobramycin was instituted, and despite an initial improvement, the patient experienced an unfavourable course and died. at postmortem examination, tricuspid valve endocarditis and purulent pericarditis with tamponade were detected. listeria monocytogenes grew in the culture of the pericardial flu ...19979255896
listeria monocytogenes infection of p388d1 macrophages results in a biphasic nf-kappab (rela/p50) activation induced by lipoteichoic acid and bacterial phospholipases and mediated by ikappabalpha and ikappabbeta degradation.as previously reported, listeria monocytogenes infection of p388d1 macrophages results in a rapid induction of nf-kappab dna-binding activity. here we show that this induction of nf-kappab activity occurs in a biphasic mode: first, a transient, ikappabalpha degradation-dependent phase of activity, also induced by the nonvirulent species listeria innocua, which is mediated by binding of the bacteria to the macrophage, or by adding listeria-derived lipoteichoic acid to the macrophage; the second p ...19979256493
listeria monocytogenes potently induces up-regulation of endothelial adhesion molecules and neutrophil adhesion to cultured human endothelial cells.infection of endothelial cells by listeria monocytogenes is an essential step in the pathogenesis of listeriosis. listeriolysin (hly) is one of its major virulence factors. in the early phase of the disease polymorphonuclear leukocytes (pmn) substantially contribute to the nonspecific anti-listerial resistance. we characterized the effects of l. monocytogenes on the expression of endothelial adhesion molecules and on subsequent pmn adhesion to cultured huvec. p-selectin, e-selectin, intracellula ...19979257863
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