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fate of gamma-irradiated listeria monocytogenes during refrigerated storage on raw or cooked turkey breast meat.the radiation resistance and ability of listeria monocytogenes atcc 7644, 15313, 43256, and 49594 to multiply on irradiated, air-packed, refrigerated raw or cooked turkey breast meat nuggets (ca. 25 g) and ground turkey breast meat was investigated. gamma-radiation d values for l. monocytogenes were significantly different on raw and cooked nuggets, 0.56 +/- 0.03 kgy and 0.69 +/- 0.03 kgy, respectively; but they were not significantly different (p < or = 0.05) on raw and cooked ground turkey mea ...19989713758
listeria monocytogenes-associated acute hepatitis in a liver transplant recipient.we report a case of listeria monocytogenes bacteriemia with liver involvement mimicking acute viral hepatitis in a liver transplant recipient. the patient presented with fever, jaundice and alanine aminotransferase levels ten times the upper limit of normal. liver biopsy showed signs of acute hepatitis and occasional granulomas. both blood and liver biopsy cultures were positive for listeria monocytogenes. the patient received a 3 week course of ampicillin and gentamicin with clinical and bioche ...19989716234
reduced intracellular activity of antibiotics against listeria monocytogenes in multidrug resistant cells.multidrug resistance is expressed not only by bacteria, but also by tumor cells and by some normal cells of the body. it enables eukaryotic cells to exclude not only cytostatic drugs but also non-cytostatic antibiotics. this was demonstrated in genetically engineered multidrug resistant (mdr) cells infected with the facultative intracellular bacterium listeria monocytogenes for all macrolide antibiotics tested (azithromycin, clarithromycin, erythromycin, josamycin, roxithromycin and spiramycin). ...19989716288
interactions of the bacterial pathogen listeria monocytogenes with mammalian cells: bacterial factors, cellular ligands, and signaling.listeria monocytogenes is a food borne pathogen which has the very unique property of crossing three barriers during infection eliciting meningitis, meningo-encephalitis and abortions with a mortality rate of about 30%. indeed, after crossing the intestinal barrier, listeria disseminates via the lymph and the blood, to the brain and/or the placenta after crossing the brain-blood barrier and/or the placental barrier. during disease, this organism infects a variety of tissues and cell types in whi ...19989717257
reduction of caecal listeria monocytogenes in leghorn chicks following treatment with a competitive exclusion culture (preempt)day-of-hatch leghorn chicks were treated by oral gavage with preempt, a continuous-flow competitive exclusion culture containing broiler caecal bacteria, followed by an oral challenge with listeria monocytogenes, to determine the effects of preempt on l. monocytogenes caecal colonization. increased (p < 0.001) concentrations of caecal propionic acid in control chicks compared with preempt-treated chicks at 3 days of age were indicative of the establishment of the preempt bacteria. caeca from con ...19989717314
macrophages and hepatocytic cells as chemokine producers in murine listeriosis.the major target organ of systemic infection with the intracellular bacterium listeria monocytogenes is the liver, to where inflammatory leukocytes are rapidly recruited. we determined by reverse transcriptase polymerase chain reaction the early chemokine response in the liver after systemic infection of mice with listeriae, and in parallel compared chemokine release from macrophages and hepatocytic cells in vitro. murine bone marrow-derived macrophages (bmm) grown in fetal calf serum-supplement ...19989717670
successful treatment of murine listeriosis and salmonellosis with levofloxacin.levofloxacin (l-ofloxacin) is a fluoroquinolone derivative. it is the active substance contained in ofloxacin with a broad spectrum of antibacterial activity against both gram-negative and gram-positive bacteria. in this work we examined the activity of levofloxacin against the facultative intracellular bacteria listeria monocytogenes and salmonella typhimurium in vitro, in tissue culture and in animal models of infection. the minimum inhibitory concentrations (mics) mic90 for salmonella enteric ...19989720471
identification of the gene encoding the alternative sigma factor sigmab from listeria monocytogenes and its role in osmotolerance.listeria monocytogenes is well known for its robust physiology, which permits growth at low temperatures under conditions of high osmolarity and low ph. although studies have provided insight into the mechanisms used by l. monocytogenes to allay the physiological consequences of these adverse environments, little is known about how these responses are coordinated. in the studies presented here, we have cloned the sigb gene and several rsb genes from l. monocytogenes, encoding homologs of the alt ...19989721294
inhibition of listeria monocytogenes by plantaricin na, an antibacterial substance from lactobacillus plantarum.a lactobacillus plantarum of vegetable origin produced a bacteriocin inhibitor to listeria monocytogenes. the antimicrobial agent was inactivated by proteolytic enzymes, was resistant to heat (100 degrees c for 30 min) and stable over a wide ph range (ph 2-10), and displayed a bactericidal mode of action. growth inhibition of l. monocytogenes depend on bacteriocin concentration. the antilisterial efficiency depended on the strain of l. monocytogenes used but was not influenced by the growth phas ...19989721606
antibiotic use in neonatal sepsis.neonatal sepsis is a life-threatening emergency and any delay in treatment may cause death. initial signs of neonatal sepsis are slight and nonspecific. therefore, in suspected sepsis, two or three days empirical antibiotic therapy should begin immediately after cultures have been obtained without awaiting the results. antibiotics should be reevaluated when the results of the cultures and susceptibility tests are available. if the cultures are negative and the clinical findings are well, antibio ...19989722468
listeria monocytogenes as a probe to study cell-mediated immunity.the intracellular bacterium listeria monocytogenes continues to serve as a model to define general paradigms of cell-mediated immunity. genetic manipulations of the bacterium and its murine host have allowed us to begin dissecting the intricate interactions between this bacterium and the immune system. as a result, we have gained new insights into the mechanisms of immune surveillance, achieved better understanding of bacterial tactics for immune evasion and developed novel strategies in vaccine ...19989722922
minimum inhibitory concentration of smoke wood extracts against spoilage and pathogenic micro-organisms associated with foods.antimicrobial activity of seven commercial smoke preparations (four liquid and three solid) was studied. the minimum inhibitory concentration (mic) was determined against a selection of food spoilage and pathogenic micro-organisms. the main smoke components were identified and quantified by gas chromatography/mass spectrometry. the most effective condensate was s2. all strains except salmonella enteritidis were inhibited by s2 with an mic < 0.5-1.5%. smoke extract l2 inhibited growth of vibrio v ...19989722997
sequence profile of the parallel beta helix in the pectate lyase superfamily.the parallel beta helix structure found in the pectate lyase superfamily has been analyzed in detail. a comparative analysis of known structures has revealed a unique sequence profile, with a strong positional preference for specific amino acids oriented toward the interior of the parallel beta helix. using the unique sequence profile, search patterns have been constructed and applied to the sequence databases to identify a subset of proteins that are likely to fold into the parallel beta helix. ...19989724624
bacterial surface proteins recognized by cd4+ t cells during murine infection with listeria monocytogenes.optimal immunity to the gram-positive pathogen listeria monocytogenes (lm) requires both cd8+ and cd4+ antigen-specific t cell responses. understanding how cd4+ t cells function in an immune response to lm and how bacterial proteins are processed to peptide/mhc class ii complexes in infected cells requires identification of these proteins. using lacz-inducible, lm-specific cd4+ t cells as probes, we identified two immunogenic lm proteins by a novel expression cloning strategy. the antigenic pept ...19989725229
the role of the bacterial membrane protein acta in immunity and protection against listeria monocytogenes.acta, an essential virulence factor of listeria monocytogenes, is an integral membrane protein that is required for intracellular motility, cell-to-cell spread, and rapid dissemination of the bacteria in the infected host. to reveal cytotoxic t cell responses against acta we introduced a recombinant soluble form of acta into the mhc class i-processing compartment of apc using a variant of listeriolysin mutated within its immunodominant mhc class i epitope. with this experimental system we demons ...19989725238
cpg dna induces sustained il-12 expression in vivo and resistance to listeria monocytogenes challenge.vertebrates have evolved innate immune defense mechanisms that recognize and respond to structural patterns that are specific to microbial molecules. one such pattern recognition system is based on unmethylated cpg dinucleotides in particular sequence contexts (cpg motifs); these motifs are common in bacterial dna but are under-represented ("cpg suppression") and methylated in vertebrate dna. mice that are injected with bacterial dna or synthetic oligodeoxynucleotides (odns) containing cpg motif ...19989725240
cloning and expression of the listeria monocytogenes scott a ptsh and ptsi genes, coding for hpr and enzyme i, respectively, of the phosphotransferase system.the phosphoenolpyruvate (pep)-dependent phosphotransferase system (pts) utilizes high-energy phosphate present in pep to drive the uptake of several different carbohydrates in bacteria. in order to examine the role of the pts in the physiology of listeria monocytogenes, we identified the ptsh and ptsi genes encoding the hpr and enzyme i proteins, respectively, of the pts. nucleotide sequence analysis indicated that the predicted proteins are nearly 70% similar to hpr and enzyme i proteins from o ...19989726852
modeling of the competitive growth of listeria monocytogenes and lactococcus lactis in vegetable broth.current mathematical models used by food microbiologists do not address the issue of competitive growth in mixed cultures of bacteria. we developed a mathematical model which consists of a system of nonlinear differential equations describing the growth of competing bacterial cell cultures. in this model, bacterial cell growth is limited by the accumulation of protonated lactic acid and decreasing ph. in our experimental system, pure and mixed cultures of lactococcus lactis and listeria monocyto ...19989726854
comparative studies of class iia bacteriocins of lactic acid bacteria.four class iia bacteriocins (pediocin pa-1, enterocin a, sakacin p, and curvacin a) were purified to homogeneity and tested for activity toward a variety of indicator strains. pediocin pa-1 and enterocin a inhibited more strains and had generally lower mics than sakacin p and curvacin a. the antagonistic activity of pediocin-pa1 and enterocin a was much more sensitive to reduction of disulfide bonds than the antagonistic activity of sakacin p and curvacin a, suggesting that an extra disulfide bo ...19989726871
characterization of a bacteriocin produced by streptococcus thermophilus 81.a new bacteriocin, produced by streptococcus thermophilus 81 has been isolated, purified and characterized. by its heat sensitivity and broad inhibitory spectrum it does not resemble any other s. thermophilus bacteriocin. the mode of action is bacteriostatic. this peptide of 32 amino acids is efficient against several bacillus species, listeria monocytogenes, salmonella typhimurium, escherichia coli, yersinia pseudotuberculosis and yersinia enterocolitica. this bacteriocin is heat labile but its ...19989728685
a comparison of listeria monocytogenes serovar 4b isolates of clinical and food origin in japan by pulsed-field gel electrophoresis.pulsed-field gel electrophoresis (pfge) patterns of 102 l. monocytogenes serovar 4b isolates from patients and foods examined in japan were compared with 16 isolates from foodborne listeriosis episodes which occurred in north america or europe. using a combination of pfge patterns with the restriction enzymes smai, apai, asci and sse8387i, 82 clinical isolates from japan were categorized into 45 pfge types: the largest group of 17 isolates (20.7%) were of the same pfge type as cultures from the ...19989728691
a rapid method for the identification and partial serotyping of listeria monocytogenes in food by pcr and restriction enzyme analysis.two highly specific primers for listeria monocytogenes were used to yield from foods such as milk, soft cheese and meat, pcr products that were cleaved with the restriction enzyme hindiii. the fragments generated allowed a distinction between two groups of l. monocytogenes serovars: serovars 1/2a and 1/2c cluster in one group and serovars 1/2b, 3b and 4b in the other subgroup. since this procedure can be completed in 24 h, an epidemiological association between human disease and suspected source ...19989728692
identification of cofilin, coronin, rac and capz in actin tails using a listeria affinity approach.actin assembly is involved in cell motility and intracellular movement of listeria monocytogenes. induction of listeria actin tails is mediated by the surface protein acta. the n-terminal domain of acta is sufficient for this function. cell components known to play a role in the actin-based motility of listeria are vasp (vasodilatator-stimulated phosphoprotein), the multiprotein arp2/3 complex and cofilin. vasp interacts with the central domain of acta. proteins interacting with the n-terminal d ...19989730980
host resistance against listeria monocytogenes is reciprocal during the course of infection in alymphoplastic aly mutant mice.the aly is a unique spontaneous autosomal recessive mutation in mice that causes a systemic defect of lymph nodes and peyer's patches. we investigated host resistance against listeria monocytogenes infection in the mutant. the 50% lethal dose of l. monocytogenes in aly/aly mice was 10-fold higher than their heterozygotes, termed aly/+mice, or their wild-type c57bl/6 mice. the bacterial growth in the spleens and livers of aly/aly mice was more efficient early in infection, and their listericidal ...19989732696
spontaneous bacterial peritonitis caused by infection with listeria monocytogenes: a case report and review of the literature.spontaneous bacterial peritonitis is a frequent and often serious complication of long-standing ascites in the presence of advanced liver disease. coliform bacteria account for the infection in most cases and are thought to be related to translocation of bacteria from the bowel into the peritoneal cavity. the empiric use of cefotaxime is well established as most of the causative organisms are sensitive to this antibiotic. however, we report on a case of spontaneous bacterial peritonitis in a pat ...19989732945
listeria monocytogenes meningitis in a penicillin-allergic paediatric renal transplant patient.currently in many centres the extended spectrum cephalosporins (e.g. cefotaxime and ceftriaxone) are being used empirically for patients with suspected bacterial meningitis. we present a case of meningitis in a penicillin allergic paediatric renal transplant patient from whose cerebrospinal fluid (csf) listeria monocytogenes was cultured, despite four days of cefotaxime therapy. the patient was successfully treated with meropenem but required neuro-endoscopic intervention for hydrocephalus.19989733389
a novel bacteriocin with a ygngv motif from vegetable-associated enterococcus mundtii: full characterization and interaction with target organisms.a novel broad-spectrum antimicrobial peptide produced by vegetable-associated enterococcus mundtii was purified and characterized, and designated mundticin. to our knowledge, this is the first report on bacteriocin production by this organism. the elucidation of the full primary amino acid sequence of mundticin (kyygngvscnkkgcsvdwgkaigiignnsaanlatggaagwsk) revealed that this antimicrobial peptide belongs to the class iia bacteriocins of lactic acid bacteria which share a highly conserved n-termi ...19989733915
characterization of listeria monocytogenes isolated from channel catfish (ictalurus punctatus).to characterize listeria monocytogenes from tissues of channel catfish for their ability to cause hemolysis and grow intracellularly in mouse macrophages.19989736389
activities of ll-37, a cathelin-associated antimicrobial peptide of human neutrophils.human neutrophils contain two structurally distinct types of antimicrobial peptides, beta-sheet defensins (hnp-1 to hnp-4) and the alpha-helical peptide ll-37. we used radial diffusion assays and an improved national committee for clinical laboratory standards-type broth microdilution assay to compare the antimicrobial properties of ll-37, hnp-1, and protegrin (pg-1). although generally less potent than pg-1, ll-37 showed considerable activity (mic, <10 microgram/ml) against pseudomonas aerugino ...19989736536
actin cytoskeleton: the arp2/3 complex gets to the point.actin filament polymerization results primarily from the addition of monomers to pre-existing filaments. recent studies have revealed that the arp2/3 protein complex, which includes two actin-related proteins, can nucleate new actin filaments, and this capacity can be enhanced by acta, a protein used by listeria to polymerize actin.19989740796
apolipoprotein e-deficient mice have impaired innate immune responses to listeria monocytogenes in vivo.apolipoprotein e (apoe) influences both innate and acquired immunity in cultured cells. to determine whether apoe affects the immune system in vivo, listeria monocytogenes (lm) was administered intraperitoneally (10(4) c.f.u.) to congenic c57bl/6 apoe-/- and +/+ mice (n = 12 in each group). survival was assessed daily for 5 days. deficiency of apoe significantly increased death by day 5 (p = 0.03). the majority of deaths occurred at day 4. extent of infection after lm administration was assessed ...19989741685
functional gene transfer from intracellular bacteria to mammalian cells.we provide evidence of direct transfer of functional dna from bacteria to mammalian cells. an escherichia coli k12 diaminopimelate auxotroph made invasive by cloning the invasin gene from yersinia pseudotuberculosis transfers dna after simple co-incubation, into a variety of mammalian cell lines. transfer efficiency was enhanced in some cells by coexpression of the gene for listeriolysin from listeria monocytogenes. expression of the acquired genes occurs in both dividing and quiescent cells. th ...19989743121
the mhc class i-restricted immune response to hiv-gag in balb/c mice selects a single epitope that does not have a predictable mhc-binding motif and binds to kd through interactions between a glutamine at p3 and pocket d.using a strain of listeria monocytogenes that stably expresses and secretes hiv gag to deliver this ag to the mhc class i pathway of ag processing, we have identified the immunodominant ctl epitope to gag in the balb/c mouse and shown that it is kd restricted. the specific motif for the peptides that bind the mhc class i molecule h-2 kd is believed to be a nonamer with residues tyrosine or phenylalanine in the second amino acid position and leucine or isoleucine in the carboxyl-terminal or ninth ...19989743362
two distinct phospholipases c of listeria monocytogenes induce ceramide generation, nuclear factor-kappa b activation, and e-selectin expression in human endothelial cells.infection of endothelial cells by listeria monocytogenes is an essential step in the pathogenesis of listeriosis. we recently reported that l. monocytogenes induces up-regulation of e-selectin and other endothelial adhesion molecules and subsequent polymorphonuclear leukocyte (pmn) adhesion into cultured human endothelial cells. in the present study, we characterized the mechanisms of enhanced e-selectin expression using l. monocytogenes wild type (egd), the isogenic in-frame deletion mutants fo ...19989743365
modulation of enzymatic activity and biological function of listeria monocytogenes broad-range phospholipase c by amino acid substitutions and by replacement with the bacillus cereus ortholog.the secreted broad-range phosphatidylcholine (pc)-preferring phospholipase c (pc-plc) of listeria monocytogenes plays a role in the bacterium's ability to escape from phagosomes and spread from cell to cell. based on comparisons with two orthologs, clostridium perfringens alpha-toxin and bacillus cereus plc (plcbc), we generated pc-plc mutants with altered enzymatic activities and substrate specificities and analyzed them for biological function in tissue culture and mouse models of infection. t ...19989746585
synergistic antibacterial action of heat in combination with nisin and magainin ii amide.lactobacillus plantarum has been exposed to mild heat at temperatures between 48 and 56 degrees c in combination with low concentrations of the lantobiotic nisin in different sequential set-ups. exposure to heat and nisin caused synergistic reductions of lact. plantarum viability. efficient antimicrobial action was dependent on the growth state of the culture as well as on levels and sequences of treatment applications. listeria monocytogenes and escherichia coli were treated at 55 degrees c in ...19989750279
antilisterial activity of enterocin 81, a bacteriocin produced by enterococcus faecium whe 81 isolated from cheese.enterocin 81, a bacteriocin produced by enterococcus faecium whe 81 previously isolated from cheese, exhibited a very narrow spectrum of activity, which is mainly directed against enterococci and listeria spp. including listeria monocytogenes. enterocin 81 activity, which was extremely rapid with maximal effect achieved within 30 min, could not be detected after treatment with various proteolytic enzymes. this activity was bactericidal in nature and induced an important efflux of intracellular m ...19989750282
survival of listeria monocytogenes in sea water and effect of exposure on thermal resistance.survival, recoverability and sublethal injury of two strains of listeria monocytogenes, scott a and an environmental strain km, on exposure to sea water at 12.8 or 20.8 degrees c was determined using in situ diffusion chambers. plate counts were used to assess recoverability and injury while 5-cyano-2,3-ditolyl tetrazolium chloride (ctc) reduction was used to determine respiratory activity. t90 values (times for 10-fold decreases in numbers of recoverable cells) on non-selective medium (tryptica ...19989750285
detection and characterization of a novel antibacterial substance produced by a lactobacillus delbrueckii strain 1043.a novel antibacterial substance produced by a strain isolated from bulgarian yellow cheese was characterized. the producer strain was identified by molecular typing to belong to the species lactobacillus delbrueckii, which is a rare producer of bacteriocins. the inhibitory agent was heat stable and active against lactic acid bacteria species and several food-borne pathogens: listeria monocytogenes, staphylococcus aureus, enterococcus faecalis, escherichia coli, yersinia enterocolitica and y. pse ...19989750290
bacteriocins inhibit glucose pep:pts activity in listeria monocytogenes by induced efflux of intracellular metabolites.glucose transport by the phosphoenolpyruvate (pep)-dependent phosphotransferase system (pts) of listeria monocytogenes is inhibited by the bacteriocins, nisin, pediocin jd and leuconocin s. to investigate the mechanism of inhibition, pts activity assays were performed with permeabilized, bacteriocin-treated l. monocytogens scott a cells. in the presence of exogenous pep, nisin stimulated the pts while both pediocin jd and leuconocin s partially inhibited its activity. these results suggested tha ...19989750302
tissue culture assays using caco-2 cell line differentiate virulent from non-virulent listeria monocytogenes strains.within the group of listeria sp., only l. monocytogenes is pathogenic for humans and numerous studies of l. monocytogenes strains have described non-virulent isolates. in this study, the potential value of two tissue culture assays (tca) was analysed to ascertain the virulence properties of l. monocytogenes strains, initially typed for virulence using the immunocompromised mouse model (icmm). the first assay assessed both the penetration into, and multiplication within, caco-2 cells (pm assay): ...19989750307
light inactivation of food-related pathogenic bacteria using a pulsed power source.the effects of high intensity light emissions, produced by a novel pulsed power energization technique (ppet), on the survival of bacterial populations of verocytotoxigenic escherichia coli (serotype 0157:h7) and listeria monocytogenes (serotype 4b) were investigated. using this ppet approach, many megawatts (mw) of peak electrical power were dissipated in the light source in an extremely short energization time (about 1 microsecond). the light source was subjected to electric field levels great ...19989750325
bacterial phospholipases and intracellular growth: the two distinct phospholipases c of listeria monocytogenes. 19989750357
reactivities of genus-specific monoclonal antibody em-6e11 against listeria species and serotypes of listeria monocytogenes grown in nonselective and selective enrichment broth media.depending on the growth medium used for enrichment of bacterial cells prior to assay, the monoclonal antibody (mab) em-6e11 recognizing listeria genus-specific epitope on 43 and 94 to 97 kda cell-surface antigens (a. k. bhunia and m. g. johnson, appl. environ. microbiol. 58:1924-1929, 1992) exhibited extensive variability in the detection of listeria species. mab em-6e11 strongly detected live cells of all listeria species and all serotypes of l. monocytogenes by elisa when cells were grown in n ...19989766076
identification of listeria monocytogenes from unpasteurized apple juice using rapid test kits.a microbiological survey of 50 retail juices was conducted in the fall of 1996. these juices were analyzed for listeria monocytogenes, escherichia coli o157:h7, salmonella, coliforms, fecal coliforms, and ph. two unpasteurized juices were positive for l. monocytogenes: an apple juice and an apple raspberry blend with a ph of 3.78 and 3.75, respectively. three l. monocytogenes isolates were characterized. the colonies were typical for listeria sp. on oxford and lithium chloride-phenylethanol-moxa ...19989766077
inactivation of listeria monocytogenes in milk by pulsed electric field.pasteurized whole, 2%, and skim milk were inoculated with listeria monocytogenes scott a and treated with high-voltage pulsed electric field (pef). the effects of milk composition (fat content) and pef parameters (electric field strength, treatment time, and treatment temperature) on the inactivation of the bacterium were studied. no significant differences were observed in the inactivation of l. monocytogenes scott a in three types of milk by pef treatment. with treatment at 25 degrees c, 1- to ...19989766078
listeria infection after liver transplantation: report of a case and review of the literature.listeria monocytogenes is a well-recognized cause of bacteremia and meningitis in immunocompromised individuals, including recipients of solid organ transplants, but has only rarely been reported following orthotopic liver transplantation (olt). most previously reported cases of listeriosis occurred months to years following liver transplantation; we describe a case of listeriosis that occurred within 1 wk of liver transplantation, shortly after discontinuation of trimethoprim-sulfamethoxazole p ...19989772060
effects of prolonged exposure to morphine and methadone on in vivo parameters of immune function in rats.in rats, two 6-week repeated dose oral toxicity studies were performed with morphine (250 and 500 mg/kg food) and methadone (200 and 400 mg/kg food), respectively. alterations in immune function were studied by assessing primary and secondary immune responses to sheep red blood cells. in addition, the ability to resist challenge with infectious agents was measured in host resistance models employing the parasite trichinella spiralis and the bacterium listeria monocytogenes. the primary and secon ...19989772098
central nervous system infection with listeria monocytogenes. 33 years' experience at a general hospital and review of 776 episodes from the literature.we reviewed 776 previously reported and 44 new cases of cns listeriosis outside of pregnancy and the neonatal period, and evaluated the epidemiologic, diagnostic, and therapeutic characteristics of this infection. among patients with listeria meningitis/meningoencephalitis, hematologic malignancy and kidney transplantation were the leading predisposing factors, but 36% of patients had no underlying diseases recognized. the infection occurred throughout life, with a higher incidence before the ag ...19989772921
[listeria monocytogenes: a rare cause of spontaneous bacterial peritonitis in liver cirrhosis]. 19989775176
bone marrow cellular composition in listeria monocytogenes infected mice detected using er-mp12 and er-mp20 antibodies: a flow cytometric alternative to differential counting.detailed assessment of bone marrow cellular composition is essential in the evaluation of various experimental in vivo systems, such as expression of transgenes, null mutations and stimulation of host defence in infection. traditional morphological analysis of mouse bone marrow is laborious, requires specific cytological expertise, and is somewhat subjective. as an alternative, we have examined whether double labelling of bone marrow with the anti-precursor monoclonal antibodies er-mp12 and er-m ...19989776572
studying m cells and their role in infection.in addition to sampling antigens, m cells are a common route for pathogen invasion. recent studies have partly defined the mechanisms by which pathogens interact with and exploit m cells as a gateway into the host. new research tools are facilitating studies on m cell infection, differentiation and function.19989778729
heat-killed listeria monocytogenes as an adjuvant converts established murine th2-dominated immune responses into th1-dominated responses.we investigated the capacity of heat-killed listeria monocytogenes (hkl), a potent stimulator of the innate immune system, as a vaccine adjuvant to modify both primary and secondary ag-specific immune responses. mice immunized with the ag keyhole limpet hemocyanin (klh) mixed with hkl generated a klh-specific primary response characterized by production of th1 cytokines and large quantities of klh-specific igg2a ab. moreover, administration of klh with hkl as an adjuvant reversed established imm ...19989780187
use of the protective antigen of erysipelothrix rhusiopathiae in the enzyme-linked immunosorbent assay and latex agglutination.to establish a safe and convenient serodiagnostic method for swine erysipelas, a purified protective protein antigen of erysipelothrix rhusiopathiae, which included a large amount of protective protein (64 kda protein), was used for enzyme-linked immunosorbent assay (elisa) and the latex agglutination (la) test. in the elisa, the antisera to four different serovars (1a, 2, 5 and 20) of e. rhusiopathiae exhibit a positive reaction, while antisera to other species of bacteria (listeria monocytogen ...19989780828
[newborn infant bacterial infections. diagnosis, treatment principles, prevention]. 19989781160
[the persistent characteristics of listeria monocytogenes isolated from different sources].a number of biological properties of l. monocytogenes was studied. significant differences in the lysozyme, "anti-interferon", rnaase and lipase activity between strains isolated from different warm-blooded animals and from environmental objects were shown. 75% of all strains under study were found to have "anti-interferon" activity, while no antilysozyme activity was detected.19989783394
interaction of listeria monocytogenes with human brain microvascular endothelial cells: inlb-dependent invasion, long-term intracellular growth, and spread from macrophages to endothelial cells.invasion of endothelial tissues may be crucial in a listeria monocytogenes infection leading to meningitis and/or encephalitis. internalization of l. monocytogenes into endothelial cells has been previously demonstrated by using human umbilical vein endothelial cells as a model system. however, during the crossing of the blood-brain barrier, l. monocytogenes most likely encounters brain microvascular endothelial cells which are strikingly different from macrovascular or umbilical vein endothelia ...19989784531
immunohistochemical detection of listeria antigens in the placenta in perinatal listeriosis.listeria monocytogenes, a worldwide pathogen, causes significant perinatal mortality and morbidity and has been implicated in spontaneous abortions, still-births, premature delivery, and neonatal sepsis, often with meningitis. maternal symptoms are frequently minimal, and diagnosis is made only if the suspicion is high and diagnostic maternal blood or amniotic fluid cultures are performed. because cultures are not routinely performed on spontaneously aborted fetuses, many authors feel that the t ...19989785135
in-vitro activity of the new ketolide antibiotic hmr 3647 against gram-positive bacteria.the comparative in-vitro activity of hmr 3647, a new ketolide antibiotic, was investigated against 492 clinical isolates of gram-positive bacteria, including multiply resistant strains, by an agar-dilution technique. all streptococci tested were inhibited by the new ketolide at concentrations < or = 0.5 mg/l. hmr 3647 was more potent than erythromycin against staphylococci. for enterococci the new compound yielded an mic90 of 8 mg/l. erysipelothrix spp., pediococcus spp., leuconostoc spp., lacto ...19989786468
detection of listeria in raw and pasteurized milk.one hundred raw milk samples from different regions of anatolia and 20 pasteurized milk samples from three different manufacturers in ankara were analyzed for the presence of listeria spp. l. monocytogenes was found in 1% of the raw milk samples and in 5% (1/20) of the pasteurized milk samples. l. innocua and l. seeligeri were found in 8 and 2% of the raw milk samples, respectively. no other species of listeria was found. the overall incidence of listeria spp. was 10% in the raw milk samples and ...19989787931
perinatal listeriosis: a population-based multicenter study in barcelona, spain (1990-1996).the aim off this study was to describe the incidence, epidemiology, clinical presentation, and outcome of perinatal listeriosis for a 7-year period (1990-1996) based on data of an active population-based surveillance project implemented in the city of barcelona, spain. there were 30 cases (20.8%) associated with pregnancy (15 pregnant women, 13 neonates, and 2 fetal deaths). the incidence of perinatal listeriosis varied from 4.1 to 0 per 10,000 live births. the proportion of perinatal cases in r ...19989788644
occurrence of listeria monocytogenes in sewage sludge.the search for salmonella is the only bacteriological index included in italian guidelines (in accordance with eu regulations) for the use of sewage sludge in agriculture. as a result, information regarding the presence of listeria monocytogenes is rather limited. we therefore decided to carry out an investigation of listeria in the sludge produced by the bologna (italy) treatment plant during the various phases of treatment. five different types of sludge were analysed (primary raw, activated, ...19989789361
a novel prfa-regulated chromosomal locus, which is specific for listeria ivanovii, encodes two small, secreted internalins and contributes to virulence in mice.several large, cell wall-associated internalins and one small, secreted internalin (inlc) have been described previously in listeria monocytogenes. using degenerate primers derived from sequenced peptides of an l. ivanovii major secreted protein, we identified a new 4.25 kb internalin locus of l. ivanovii, termed i-inlfe. the two proteins encoded by this locus, i-inle and i-inlf, belong to the group of small, secreted internalins. southern blot analyses show that the i-inlfe locus does not occur ...19989791184
[infectious aneurysm due to listeria monocytogenes: a new case and review of the literature].infections due to listeria monocytogenes usually occur in pregnant women, in the elderly and in immunocompromised patients. arterial aneurysms due to this germ are rare. only 16 cases have been previously described in the literature.19989793154
the effect of reuterin on listeria monocytogenes and escherichia coli o157:h7 in milk and cottage cheese.a broad-spectrum reuterin produced during anaerobic fermentation of glycerol by lactobacillus reuteri strain 12002 was found to be inhibitory and bactericidal for listeria monocytogenes and escherichia coli o157:h7. lyophilized reuterin was prepared by a two-step fermentation process. a batch fermentation in a 15-liter fermentor was applied to produce a maximum biomass of l. reuteri using a modified mrs broth at ph 4.3. further, harvested cells were used to ferment glycerol (250 mm) under anaero ...19989798141
antimicrobial effects of d-3-phenyllactic acid on listeria monocytogenes in tsb-ye medium, milk, and cheese.d-3-phenyllactic acid is a compound with anti-listeria activity which is produced and secreted by the yeastlike fungus, geotrichum candidum. this compound has a bactericidal effect independent of the physiological state of listeria monocytogenes when added at a concentration of 7 mg/ml to tryptic soy broth supplemented with yeast extract (tsb-ye). an initial l. monocytogenes population of 10(5) cfu/ml was reduced 100-fold (2 log) after 4 days of culture at 25 degrees c in tsb-ye containing d-3-p ...19989798142
influence of environmental stress on the kinetics and strength of attachment of listeria monocytogenes scott a to buna-n rubber and stainless steel.attachment and detachment of listeria monocytogenes scott a to buna-n rubber and stainless steel under varying conditions of temperature and ph were investigated using model systems. numbers of attached cells increased with increasing attachment temperature (10 to 45 degrees c) and time (up to 120 min) for both test surfaces. compared to buna-n rubber, the rate of attachment to stainless steel was markedly more rapid for all temperature and ph conditions studied and could not be calculated. rate ...19989798143
effect of environmental stress on the ability of listeria monocytogenes scott a to attach to food contact surfaces.attachment of listeria monocytogenes scott a to buna-n rubber and stainless steel under different temperature and ph conditions at the time of cell growth or at the time of attachment was investigated. all experiments were conducted using sterile phosphate buffer to avoid cell growth during exposure to the test surfaces. numbers of attached cells increased with increasing attachment temperature (10 to 45 degrees c) and exposure time for both test surfaces. maximum levels of attached cells were o ...19989798144
the contamination of pâté with listeria monocytogenes--results from the 1994 european community-coordinated food control program for england and wales.the listeria monocytogenes contamination of 3,065 pâté products sampled at the point of retail sale in england and wales was examined. ninety-seven percent of samples were free of contamination with l. monocytogenes, 2.0% (60) had levels of less than 200 cfu/g, and 0.6% (18) had levels of 200 cfu/g or more. fish and seafood pâté were significantly more commonly contaminated by l. monocytogenes than other pâté types (chi 2 test, p = 0.001). pâté obtained from small retail shops was significantly ...19989798145
efficacy of spray application of chlorinated water in killing pathogenic bacteria on raw apples, tomatoes, and lettuce.washing whole and cut produce by dipping or submerging in chlorinated water has a sanitizing effect, although reduction in microbial populations is minimal and is usually less than 100-fold. a study was undertaken to evaluate the efficacy of a spray application of chlorine in killing salmonella, escherichia coli o157:h7, listeria monocytogenes, yeasts and molds, and total aerobic mesophilic microorganisms on whole apples, tomatoes, and lettuce leaves. inoculated produce was treated (sprayed and ...19989798146
antibiotic resistance of salmonella spp. and listeria spp. isolates from traditionally made fresh sausages in greece.sixty-five samples of traditionally made fresh sausages obtained from retail shops and butcher shops in northern greece were screened for the presence of salmonella spp. and listeria spp. salmonella spp. were found in 20% of the samples tested (54% salmonella typhimurium and 46% salmonella enteritidis). the prevalence of listeria spp. in the samples was 26% (12% listeria monocytogenes, 76% listeria innocua, and 12% listeria welshimeri). nine of 13 salmonella isolates were found to be resistant t ...19989798159
susceptibility of antibiotic-resistant and antibiotic-sensitive foodborne pathogens to acid anionic sanitizers.acid anionic sanitizers for treatment of fruits and vegetables were prepared using ingredients generally recognized as safe by the u.s. food and drug administration or anionic surfactants and organic acid food additives. they met the regulatory definition as sanitizers by showing bactericidal efficacy of 99.999% in 30 s against staphylococcus aureus atcc 6538 and escherichia coli atcc 11229. these sanitizers showed a broad spectrum of microbicidal activity against both gram-positive and gram-neg ...19989798163
a small outbreak of listeriosis associated with smoked mussels.two perinatal listeriosis cases in auckland, new zealand, which were diagnosed during november and december 1992 gave histories of consuming brand x smoked mussels. listeria monocytogenes was isolated from an unopened packet of mussels collected from the refrigerator of one of the cases. cultures of l. monocytogenes from the two patients were indistinguishable from those recovered from the mussels by serogrouping and dna macrorestriction analysis using pulsed-field gel electrophoresis (pfge). pf ...19989801198
interferon gamma derived from cd4(+) t cells is sufficient to mediate t helper cell type 1 development.interferon gamma (ifn-gamma) has been implicated in t helper type 1 (th1) cell development through its ability to optimize interleukin 12 (il-12) production from macrophages and il-12 receptor expression on activated t cells. various systems have suggested a role for ifn-gamma derived from the innate immune system, particularly natural killer (nk) cells, in mediating th1 differentiation in vivo. we tested this requirement by reconstituting t cell and ifn-gamma doubly deficient mice with wild-typ ...19989802977
listeria monocytogenes virulence factors that stimulate endothelial cells.listeria monocytogenes infection of endothelial cells upregulates surface expression of adhesion molecules and stimulates neutrophil adhesion to infected cell monolayers. the experiments presented here tested the roles of specific bacterial virulence factors as triggers for this inflammatory phenotype and function. human umbilical vein endothelial cell (huvec) monolayers were infected with wild-type l. monocytogenes or l. monocytogenes mutants; then surface expression of e-selectin and neutrophi ...19989423863
physiological and biochemical aspects of the acid survival of listeria monocytogenes.the physiological aspects of the response to acidic conditions and the correlated protein synthesis were studied by using listeria monocytogenes grown in a chemically defined synthetic medium. this growth was greatly affected by ph of the medium. it decreased when ph declined and was arrested at ph 4. when ph went under 4, the bacteria began to die. if the bacteria had been adapted to an intermediary sublethal ph before imposition of lethal ph stress, they would have resisted better lethal ph. a ...199812501427
acetoin production as an indicator of growth and metabolic inhibition of listeria monocytogenes.it has been shown that listeria monocytogenes produces acetoin from glucose under aerobic conditions. a defined medium with glucose as the sole carbon source was used in an aerobic shake flask culture to reliably produce acetoin. acetoin, the reactive compound in the voges-proskauer test, was assayable in the medium and was used to quantify the metabolic response when inhibitors were added to the medium. inhibitors such as lactic, acetic, propionic and benzoic acids were used to demonstrate the ...199815244053
the sophisticated survival strategies of the pathogen listeria monocytogenes.the function of the acta protein of listeria monocytogenes has been partially elucidated. these results illustrate the sophistication with which intracellular pathogens like listeria use the host cell to their advantage, and have provided new insights into some of the molecular mechanisms of complex cell functions such as actin-promoted cell motility. the clarification of these processes is of fundamental importance not only for understanding elementary processes such as development and growth, ...199810943336
[identification of listeria monocytogenes by pcr method].to establish a rapid, sensitive and specific polymerase chain reaction (pcr) method for detection of listeria monocytogenes (lm).199810322746
[use of pcr methods for identification of listeria monocytogenes in milk].the aim of this work was to estimate the limit of listeria monocytogenes cfu in polymerase chain reaction (pcr) for a dna fragment of listeriolysine o (hly a) gene. the pcr method, with used primers selected in areas of the listeriolysin o gene, allows to differentiate l. monocytogenes strains from other listeria species. the amplified fragment (456 bp) of hly a gene was obtained for all strains l. monocytogenes and no other listeria species. the pcr method with the selected primers allowed to d ...199810222740
kinetics of interferon-gamma production and its comparison with anti-listeriolysin o detection in experimental bovine listeriosis.the kinetics of the production of interferon gamma (ifn-gamma) in whole blood culture and its comparison with anti-listeriolysin o (allo) detection by elisa were studied during oral infection of calves with listeria monocytogenes. culture filtrate antigen (cfa), listeriolysin o (llo), and sonicated antigen (sa) were used to prime the peripheral blood mononuclear cells (pbmcs) and the plasma from orally infected calves. ifn-gamma and allo appeared as early as day 7 of an oral infection. ifn-gamma ...199810066124
absence of escherichia coli, listeria monocytogenes, and klebsiella pneumoniae antigens within inflammatory bowel disease tissues.escherichia coli, listeria, and streptococcal antigens have been found in crohn's disease tissues. antibodies to klebsiella pneumoniae have been found in patients with inflammatory bowel disease and ankylosing spondylitis. the presence of these bacterial antigens in crohn's granulomas would be of aetiological interest, while their presence in ulcers alone would be more likely to indicate secondary infection.19989930068
suppression of lymphoproliferation by alveolar macrophages in the guinea pig.the relationship between alveolar macrophages (am) and lymphocytes may be important in the early establishment of infection with mycobacterium tuberculosis. am in several species have been shown to suppress lymphoproliferation by producing inhibitors that include nitric oxide (no).199810645450
rapid membrane capture pcr-based method for detection of listeria species. 199810909835
listeria monocytogenes septic arthritis in a natural joint: report of a case and review. 199811864314
antimicrobial resistance in listeria monocytogenes from humans and food in the uk, 1967--96. 199811864358
bacterial colonization and biofilm development on minimally processed vegetables.bacterial biofilms have been observed and reported on food and food-processing surfaces and can contribute to increased risks for product quality and food safety. the colonization of fruit and vegetables by pectynolitic bacteria like pseudonomas fluorescens attributable to conditions such as soft rot, can also manifest as biofilms. a developed biofilm structure can provide a protective environment for pathogens such as listeria monocytogenes reducing the effectiveness of sanitisers and other inh ...199821182692
enteric microflora in ibd: pathogens or commensals?: both pathogenic and normal enteric microflora can induce and perpetuate chronic intestinal inflammation with systemic manifestations in genetically susceptible hosts. at the present time, there is no convincing indication that the majority of cases of ulcerative colitis or crohn's disease is caused by persistent infection by mycobacterium paratuberculosis, measles, listeria monocytogenes, or helicobacter species, but this possibility remains a valid hypothesis. transient infection with any of ...199723282809
rhomboencephalitis caused by listeria monocytogenes.listerial rhomboencephalitis is a rare, devastating treatable disease. a previously well 72-year-old man presented with a one-week history of fever and headache. four days before admission he developed right facial numbness and ataxia. diagnosis and treatment are described, including the relevant clinical, laboratory and radiological findings.199722514485
[not available].to review the epidemiology, risk factors, clinical features and outcomes of listeria monocytogenes infection in the eastern townships of quebec, a retrospective study was completed over the period 1976 to 1995. cases were identified from positive cultures and diagnosis given by the infectious diseases service of the centre hospitalier universitaire de sherbrooke, sherbrooke, quebec. a total of 12 cases were in the study. septicemia not related to pregnancy (four of 12) and meningitis (six of 12) ...199722514474
subinhibitory concentrations of gentamicin reduce production of listeriolysin, the main virulence factor of listeria monocytogenes. 199711864119
a simple procedure for determining the presence and concentration of listeria monocytogenes in dairy products.this paper presents a simple method for determining both the presence and concentration of listeria monocytogenes in dairy products. the method involves application of the most probable number (mpn) technique and enrichment of a 25 g sample. our tests showed that the mpn correlates with the colony forming units (cfu), and estimated concentrations of as low as 1 bacterium/gr or less. we also studied the influence of listeria innocua as an accompanying flora. we detected l. monocytogenes, even in ...199710932725
bactericidal effect of enterocin 4 on listeria monocytogenes in a model dairy system.enterococcus faecalis inia 4 produced the bacteriocin enterocin 4 during growth in raw ewe's milk at 30 degrees c. enterocin activity reached 2,200 to 3,600 au/ml after 8 h, with a 1 to 8% (vol/vol) level of inoculum from an 18-h culture. an enterocin activity of 500 au/ml significantly decreased counts of listeria monocytogenes ohio when incubated for 6 h in a model system consisting of filtrates from cultures of e. faecalis inia 4 in raw ewe's milk, at ph 6.0 and 30 degrees c. however, an ente ...199710465036
antimicrobial activity of sulfur compounds derived from cabbage.selected sulfur compounds found in cabbage and its fermentation product, sauerkraut, were tested for minimum inhibitory concentration (mic) against growth of 15 species of bacteria and 4 species of yeasts. s-methyl-l-cysteine sulfoxide, sinigrin, and dimethyl sulfide at 500 ppm were not inhibitory to any of the bacteria and yeasts tested. dimethyl disulfide at 500 ppm retarded some, but did not prevent growth of any of the test microorganisms. dimethyl trisulfide had an mic to bacteria of 200 pp ...199710465044
isolation and identification of antimicrobial furocoumarins from parsley.photoactive furocoumarins extracted from four varieties of fresh and freeze-dried parsley leaves inhibited a dna repair-deficient escherichia coli in a photobiological assay. using media-modified assays, the human pathogens e. coli o157:h7 and listeria monocytogenes, the spoilage microorganism erwinia carotovora, and listeria innocua were also inhibited. pseudomonas fragi was not inhibited. minimum concentrations of forest green parsley powder in agar which showed inhibition ranged from 0.12% to ...199710465045
effect of "siljo" fermentation on growth of staphylococcus aureus, bacillus cereus and listeria monocytogenes.the fate of staphylococcus aureus, bacillus cereus, and listeria monocytogenes in control gruel and fermenting "siljo" was assessed. s. aureus reached levels of 10(8) cfu/ml within 48 h in the control gruel. in fermenting "siljo" the count decreased all through the fermentation time. b.cereus was completely inhibited in fermenting "siljo" within 24 h, whereas it survived until 72 h in the control gruel. complete inhibition of l.monocytogenes was noted at 48 h in fermenting "siljo". l.monocytogen ...199710214435
[a case report of listeria monocytogenes infection in a patient with aids. efficacy of treatment with cotrimoxazole associated with rhug-csf (filgrastim)].listeriosis is an emerging opportunistic infection in the immunocompromised host. a case of sepsis due to listeria monocytogenes in a patient with advanced hiv infection and severe neutropenia, treated for an underlying non-hodgkin's lymphoma, is described. therapy with cotrimoxazole associated with rhug-csf (filgrastim) led to a rapidly favourable clinical and microbiological outcome, and to the correction of concurrent neutropenia. the case report is discussed according to a literature review ...199714966399
inhibition of listeria monocytogenes by piscicolin 126 in milk and camembert cheese manufactured with a thermophilic starter.the effect of bacteriocin, piscicolin 126, on the growth of listeria monocytogenes and cheese starter bacteria was investigated in milk and in camembert cheese manufactured from milk challenged with 10(2) cfu ml(-1) l. monocytogenes. in milk incubated at 30 degrees c, piscicolin 126 added in the range of 512-2,048 au ml(-1) effectively inhibited growth of l. monocytogenes for more than 20 d when challenged with approximately 10(2) cfu ml(-1) l. monocytogenes. at higher challenge levels (10(4) an ...199712455889
modelling the growth, survival and death of listeria monocytogenes.in this paper, the predictive microbiology approach has been generalized to the study of growth, survival and death of listeria monocytogenes. as this micro-organism is involved in food poisoning, its growth, survival and death were studied as functions of low temperatures, nacl and phenol compounds, in a synthetic medium, by a factorially designed experiment. a significant inactivation of l. monocytogenes was obtained with 20 ppm of phenol and 4% (w/v) nacl at temperatures from 4 to 12 degrees ...199712455898
a comparison of quantitative structure-activity relationships for the effect of benzoic and cinnamic acids on listeria monocytogenes using multiple linear regression, artificial neural network and fuzzy systems.the ability of artificial neural networks (ann), fuzzy systems (fs) and multiple linear regression (mlr) to fit the biological activity surface describing the inhibition of listeria monocytogenes by benzoic and cinnamic acid derivatives was compared. mlr and ann were also compared for their ability to select the properties that best describe the biological activity of the compounds. the criteria used for comparing surface fits of all models were the coefficient of determination r2 and the standa ...199712452590
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