Publications

comparative antimicrobial susceptibility of listeria monocytogenes, l. innocua, and l. welshimeri.	the current study compared antimicrobial susceptibility of listeria innocua, l. welshimeri, and l. monocytogenes isolated from various sources. antimicrobial susceptibility testing was performed using a microbroth procedure with sensititre minimum inhibitory concentration plates containing 18 antimicrobials. resistant isolates were analyzed for the presence of antimicrobial resistance genes using pcr. the majority of l. monocytogenes isolates were resistant to oxacillin (99%, 89/90) and ceftriax ...	2009	19216646
quantitative risk assessment of listeria monocytogenes in french cold-smoked salmon: ii. risk characterization.	a model for the assessment of exposure to listeria monocytogenes from cold-smoked salmon consumption in france was presented in the first of this pair of articles (pouillot et al., 2007, risk analysis, 27:683-700). in the present study, the exposure model output was combined with an internationally accepted hazard characterization model, adapted to the french situation, to assess the risk of invasive listeriosis from cold-smoked salmon consumption in france in a second-order monte carlo simulati ...	2009	19220799
interleukin-18-related genes are induced during the contraction phase but do not play major roles in regulating the dynamics or function of the t-cell response to listeria monocytogenes infection.	proinflammatory cytokines, such as gamma interferon (ifn-gamma), impact aspects of t-cell responses after infection, including expansion, contraction, and memory formation. interleukin-18 (il-18) functions as a proinflammatory cytokine by stimulating the production of ifn-gamma from multiple cell types and accentuating the development of th1 cd4 t-cell responses. focused microarray analyses revealed upregulation of il-18 and il-18 receptor genes in cd8 t cells during the contraction phase. based ...	2009	19223481
model systems allowing quantification of sensitivity to disinfectants and comparison of disinfectant susceptibility of persistent and presumed nonpersistent listeria monocytogenes.	to determine if listeria monocytogenes persistent strains differ from presumed nonpersistent strains in disinfection susceptibility and to examine the influence of attachment and nacl on susceptibility.	2009	19226386
screening and characterization of monoclonal antibodies to the surface antigens of listeria monocytogenes serotype 4b.	this study aims to develop and characterize monoclonal antibodies (mabs) with high specificity and affinity for surface antigens of an epidemiologically important serotype 4b of listeria monocytogenes.	2009	19226395
occurrence and distribution of listeria monocytogenes and other listeria species in ready-to-eat and raw meat products.	the present study was undertaken to estimate the occurrence and distribution of listeria monocytogenes and other listeria species in ready-to-eat food items (pasteurized milk, cheese, ice cream, and cakes) and raw meat products (minced beef, pork, and chicken carcasses). a total of 711 randomly selected samples were collected from supermarkets and pastry shops in addis ababa, ethiopia. listeria monocytogenes and other listeria species were isolated and identified according to the techniques reco ...	2009	19226932
listeriosis.	listeria monocytogenes, a small, facultative anaerobic, gram-positive motile bacillus, is an important cause of foodborne illness which disproportionately affects pregnant women and their newborns. listeria infects many types of animals and contaminates numerous foods including vegetables, milk, chicken and beef. this organism has a unique proclivity to infect the fetoplacental unit with the ability to invade cells, multiply intracellularly and be transmitted cell-to-cell. the organism possesses ...	2009	19231307
prevalence of low-virulence listeria monocytogenes strains from different foods and environments.	various studies have demonstrated variations in the levels of virulence of different l. monocytogenes strains. in our laboratory, a plaque-forming assay followed by subcutaneous footpad inoculation of mice enabled us to estimate the prevalence of the low-virulence strains. this value fell from 16.3% to 1.7% with bacteria collected before 1994 and after 1997 respectively. this could be related to the modification in 1997 of the reference method en iso 11 290-1 of listeria detection which recommen ...	2009	19232447
programming for cd8 t cell memory development requires il-12 or type i ifn.	inflammation can have both positive and negative effects on development of cd8 t cell memory, but the relative contributions and cellular targets of the cytokines involved are unclear. using cd8 t cells lacking receptors for il-12, type i ifn, or both, we show that these cytokines act directly on cd8 t cells to support memory formation in response to vaccinia virus and listeria monocytogenes infections. development of memory to vaccinia is supported predominantly by il-12, whereas both il-12 and ...	2009	19234173
selective priming and expansion of antigen-specific foxp3- cd4+ t cells during listeria monocytogenes infection.	the foxp3-expressing subset of regulatory cd4(+) t cells have defined ag specificity and play essential roles in maintaining peripheral tolerance by suppressing the activation of self-reactive t cells. similarly, during chronic infection, pathogen-specific foxp3-expressing cd4(+) t cells expand and actively suppress pathogen-specific effector t cells. herein, we used mhc class ii tetramers and foxp3(gfp) knockin mice to track the kinetics and magnitude whereby pathogen-specific foxp3(+)cd4(+) an ...	2009	19234199
septin 11 restricts inlb-mediated invasion by listeria.	septins are filament-forming gtpases implicated in several cellular functions, including cytokinesis. we previously showed that sept2, sept9, and sept11 colocalize with several bacteria entering into mammalian non-phagocytic cells, and sept2 was identified as essential for this process. here, we investigated the function of sept11, an interacting partner of sept9 whose function is still poorly understood. in uninfected hela cells, sept11 depletion by sirna increased cell size but surprisingly di ...	2009	19234302
transfer of plasmid-mediated resistance to tetracycline in pathogenic bacteria from fish and aquaculture environments.	the transferability of a large plasmid that harbors a tetracycline resistance gene tet(s), to fish and human pathogens was assessed using electrotransformation and conjugation. the plasmid, originally isolated from fish intestinal lactococcus lactis ssp. lactis kya-7, has potent antagonistic activity against the selected recipients (lactococcus garvieae and listeria monocytogenes), preventing conjugation. therefore the tetracycline resistance determinant was transferred via electroporation to l. ...	2009	19236483
stimulation of the molecule 4-1bb enhances host defense against listeria monocytogenes infection in mice by inducing rapid infiltration and activation of neutrophils and monocytes.	the tumor necrosis factor receptor family molecule 4-1bb (cd137) has diverse roles in adaptive and innate immune responses. however, little is known of its role in bacterial infections. previously, we showed that 4-1bb-deficient mice have enhanced susceptibility to listeria monocytogenes infection, and mice pretreated with agonistic anti-4-1bb antibody (3e1) were much more resistant to l. monocytogenes infection than mice treated with control antibody. in this study, we report that stimulating 4 ...	2009	19237524
physical properties of gelidium corneum-gelatin blend films containing grapefruit seed extract or green tea extract and its application in the packaging of pork loins.	edible gelidium corneum-gelatin (gcg) blend films containing grapefruit seed extract (gfse) or green tea extract (gte) were manufactured, and the quality of pork loins packed with the film during storage was determined. tensile strength (ts) and water vapor permeability (wvp) of the films containing gfse or gte were better than those of the control. the film's antimicrobial activity against escherichia coli o157:h7 and listeria monocytogenes increased with increasing antimicrobial concentration, ...	2009	19200087
antimicrobial efficacy of zinc oxide quantum dots against listeria monocytogenes, salmonella enteritidis, and escherichia coli o157:h7.	zinc oxide quantum dots (zno qds) are nanoparticles of purified powdered zno. these were evaluated for antimicrobial activity against listeria monocytogenes, salmonella enteritidis, and escherichia coli o157:h7. the zno qds were utilized as a powder, bound in a polystyrene film (zno-ps), or suspended in a polyvinylprolidone gel (zno-pvp). bacteria cultures were inoculated into culture media or liquid egg white (lew) and incubated at 22 degrees c. the inhibitory efficacies of zno qds against 3 pa ...	2009	19200107
external concentration of organic acid anions and ph: key independent variables for studying how organic acids inhibit growth of bacteria in mildly acidic foods.	although the mechanisms by which organic acids inhibit growth of bacteria in mildly acidic foods are not fully understood, it is clear that intracellular accumulation of anions is a primary contributor to inhibition of bacterial growth. we hypothesize that intracellular accumulation of anions is driven by 2 factors, external anion concentration and external acidity. this hypothesis follows from basic chemistry principles that heretofore have not been fully applied to studies in the field, and it ...	2009	19200113
performance testing of six chromogenic aloa-type media for the detection of listeria monocytogenes.	the aim of the study was to test the performance of commercially available chromogenic plating media for detection and enumeration of the food-borne pathogen listeria monocytogenes. a wide range of chromogenic media similar to agar listeria according to ottaviani and agosti (aloa) were compared using palcam agar, according to van netten et al.	2009	19200329
isolation and identification of antibacterial compounds from thymus kotschyanus aerial parts and dianthus caryophyllus flower buds.	the aerial parts of thymus kotschyanus boiss. and hohen. (lamiaceae) and flower buds of dianthus caryophyllus l. (caryophyllaceae) have been traditionally implemented in the treatment of wounds, throat and gum infections and gastro-intestinal disorder by the indigenous people of northern iraq, although the compounds responsible for the medicinal properties have not been identified. in this study, antibacterial compounds from both plants were isolated and characterized, and the biological activit ...	2009	19200700
streptococcus-, shigella-, and listeria-induced autophagy.	autophagy has recently been described as an intrinsic host defense system for recognizing and eliminating intracellular-invading bacterial pathogens. some cytoplasmic-invading bacteria are trapped through the process of autophagy and are ultimately degraded within autolysosomal compartments. however, others exhibit highly evolved maneuvers for circumventing autophagic recognition and are capable of surviving and replicating within the cytoplasm. in this chapter, we describe bacterial infectious ...	2009	19200893
dynamic model of heat inactivation kinetics for bacterial adaptation.	the weibullian-log logistic (well) inactivation model was modified to account for heat adaptation by introducing a logistic adaptation factor, which rendered its "rate parameter" a function of both temperature and heating rate. the resulting model is consistent with the observation that adaptation is primarily noticeable in slow heat processes in which the cells are exposed to sublethal temperatures for a sufficiently long time. dynamic survival patterns generated with the proposed model were in ...	2009	19201963
mucosal vaccine using ctl epitope-pulsed dendritic cell confers protection for intracellular pathogen.	effective protective immunity against respiratory infections with intracellular pathogens requires pathogen-specific cytotoxic t cells (ctl) in the lung. however, vaccines that induce pathogen-specific ctl in the lung are poorly explored. dendritic cells (dc) have increasingly been exploited as vaccines against infections. however, few studies have investigated the ability of mucosal dc vaccines to elicit protective ctl responses in the lung. our objective was to develop an efficacious mucosal d ...	2009	19202004
multiple effector mechanisms induced by recombinant listeria monocytogenes anticancer immunotherapeutics.	listeria monocytogenes is a facultative intracellular gram-positive bacterium that naturally infects professional antigen presenting cells (apc) to target antigens to both class i and class ii antigen processing pathways. this infection process results in the stimulation of strong innate and adaptive immune responses, which make it an ideal candidate for a vaccine vector to deliver heterologous antigens. this ability of l. monocytogenes has been exploited by several researchers over the past dec ...	2009	19203646
inflammatory pseudotumor of the heart caused by listeria monocytogenes infection.	inflammatory pseudotumor (ipt) of the heart is rare and of unknown etiology. we present a case of cardiac ipt caused by listeria monocytogenes that evolved following gastroenteritis in a previously healthy child. l. monocytogenes, known to cause acute invasive infections, has not been reported previously as a cause of cardiac infection in children or of ipt. the literature concerning infectious ipt is reviewed.	2009	19203798
effects of ph and oil-in-water emulsions on growth and physicochemical cell surface properties of listeria monocytogenes: impact on tolerance to the bactericidal activity of disinfectants.	this study characterizes the effects of an acidic ph and an emulsified oil-in-water phase in a culture medium on the behavior of listeria monocytogenes. two strains were tested, scott a and cip 78.39, and exhibited similar responses to growth media. first of all, the results showed that the emulsified oil phase had no effect on growth kinetics, whereas acidification of the initial ph (from 7.2 to 5.2) reduced both growth rates and growth yields. secondly, physicochemical cell surface properties ...	2009	19203811
control of foodborne pathogens and soft-rot bacteria on bell pepper by three strains of bacterial antagonists.	forty-two representative strains of native bacteria associated with fresh peeled baby carrots were isolated and characterized. two of these strains, identified as pseudomonas fluorescens ag3a (pf ag3a) and bacillus yd1, were evaluated in conjunction with another known antagonist, p. fluorescens 2-79 (pf 2-79), for their potential as biocontrol agents of human pathogens (listeria monocytogenes, yersinia enterocolitica, salmonella enterica, and escherichia coli o157:h7) and soft-rot bacteria (erwi ...	2009	19205468
detection of listeria monocytogenes in commercially broken unpasteurized liquid egg in japan.	unpasteurized liquid whole-egg samples were collected from six and seven commercial establishments across japan in 1993 and 1994 and in 2005, respectively. the samples were tested for the presence of listeria spp. and listeria monocytogenes. detection rates of the listeria spp. were greatly different among the egg-breaking facilities, with a range of 8 to 55%. there was no significant difference in the contamination rate between the samples from 1993 and 1994 and from 2005. l. monocytogenes was ...	2009	19205482
[ventriculitis secondary to listeria monocytogenes].		2009	19206067
pathogen trafficking pathways and host phosphoinositide metabolism.	phosphoinositide (pi) glycerolipids are key regulators of eukaryotic signal transduction, cytoskeleton architecture and membrane dynamics. the host cell pi metabolism is targeted by intracellular bacterial pathogens, which evolved intricate strategies to modulate uptake processes and vesicle trafficking pathways. upon entering eukaryotic host cells, pathogenic bacteria replicate in distinct vacuoles or in the host cytoplasm. vacuolar pathogens manipulate pi levels to mimic or modify membranes of ...	2009	19208094
herpesvirus latency and symbiotic protection from bacterial infection.		2009	19210221
gamma-herpesvirus-induced protection against bacterial infection is transient.	herpesviruses are widely disseminated in the population and establish lifelong latency, which is associated with a variety of pathological consequences. a recent report showed that mice latently infected with either murine gamma-herpesvirus-68 (gammahv68) or murine cytomegalovirus (mcmv), mouse pathogens genetically similar to the human herpesviruses, epstein-barr virus, kaposi's sarcoma-associated herpesvirus, and cytomegalovirus, had enhanced resistance to subsequent bacterial infection, sugge ...	2009	19210230
structural basis for autoinhibition and activation of auto, a virulence-associated peptidoglycan hydrolase of listeria monocytogenes.	during a bacterial infection, each successive step is orchestrated by a dedicated set of virulence factors. in gram-positive bacteria, the presentation or release of such factors is crucially dependent on the continual remodelling of the cell wall. we have investigated the autolysin or peptidoglycan hydrolase auto (lmo1076) from the human pathogen listeria monocytogenes to structurally and biochemically underpin its role in host cell invasion. we demonstrate that auto is an n-acetylglucosaminida ...	2009	19210622
expression of the reporter genes lacz and egfp in human glioblastoma cells using listeria monocytogenes as vector for gene transfer.	glioblastoma has become a model target for viral gene therapy approaches. to circumvent some of the inherent problems of viral vectors, we examined the feasibility of listeria monocytogenes for foreign gene expression in glioblastoma cells.	2009	19215661
overcoming cancer immune tolerance and escape.	although her2/neu-targeted cancer vaccines have shown initial promise in the adjuvant setting, a therapeutic vaccine remains elusive due to the tumor escape mechanisms of established cancer. as described by seavey et al. in this issue of ccr, a listeria-delivered vaccine may help overcome immune tolerance, leading to an effective therapeutic vaccine.	2009	19188142
a novel human her-2/neu chimeric molecule expressed by listeria monocytogenes can elicit potent hla-a2 restricted cd8-positive t cell responses and impact the growth and spread of her-2/neu-positive breast tumors.	the aim of this study was to efficiently design a novel vaccine for human her-2/neu-positive (hher-2/neu) breast cancer using the live, attenuated bacterial vector listeria monocytogenes.	2009	19188163
prevention of autoimmune disease by induction of tolerance to toll-like receptor 7.	activation of toll-like receptors (tlr) contributes to the initiation and maintenance of chronic inflammation in autoimmune diseases, yet repeated exposure to a tlr agonist can induce hyporesponsiveness to subsequent tlr stimulation. here, we used a synthetic tlr7 agonist, 9-benzyl-8-hydroxy-2-(2-methoxyethoxy) adenine (sm360320, 1v136) to study tlr7 induced attenuation of inflammatory responses and its application to autoimmune diseases. repeated low dose administration of this tlr7 agonist ind ...	2009	19188597
listeria monocytogenes infection in the face of innate immunity.	pathogen recognition and induction of immune responses are important for efficient elimination of infection. however, pathogens such as listeria monocytogenes employ strategies to evade or modulate these defences, thus creating a more favourable environment that ensures their survival and pathogenesis. new insights into these strategies, particularly those targeting innate immunity, have recently emerged. l. monocytogenes is initially detected at the cell surface or in phagosomes by toll-like re ...	2009	19191786
listeria monocytogenes internalin and e-cadherin: from structure to pathogenesis.	many bacterial pathogens that invade non-phagocytic cells first interact with host cell surface receptors. adhesion to the host cell is followed by the activation of specific host signalling pathways that mediate bacterial internalization. the food-borne gram-positive bacterium listeria monocytogenes makes use of two surface proteins, internalin (inla) and inlb to engage in a species-specific manner the adhesion molecule e-cadherin and the hepatocyte growth factor receptor met, respectively, to ...	2009	19191787
cytotoxic t-lymphocyte antigen 4 blockade augments the t-cell response primed by attenuated listeria monocytogenes resulting in more rapid clearance of virulent bacterial challenge.	cytotoxic t-lymphocyte antigen 4 (ctla-4) uniformly suppresses antigen-specific t cells during chronic infection with bacterial, parasitic or viral pathogens. however, the importance of ctla-4 in controlling the t-cell response during acute infection or after priming with live attenuated vaccine vectors has not been well characterized. since strategies aimed at blocking ctla-4 are being actively developed to therapeutically augment t-cell-mediated immunity, the effects of ctla-4 blockade on t-ce ...	2009	19191906
combined tlr2 and tlr4 ligation in the context of bacterial or helminth extracts in human monocyte derived dendritic cells: molecular correlates for th1/th2 polarization.	recognition of pathogens by dendritic cells (dcs) through interaction with pattern recognition receptors, including toll like receptors (tlr), is crucial for the initiation of appropriate polarized t helper (th) cell responses. yet, the characteristics and differences in molecular profiles of dcs with different t cell polarizing capacities are still poorly defined. to address this issue, the molecular profile of human monocyte derived dcs was characterized after exposure to tlr4 ligand lps in co ...	2009	19193240
eight-plex pcr and liquid-array detection of bacterial and viral pathogens in cerebrospinal fluid from patients with suspected meningitis.	we here report on the development of a novel multiplex pcr with product detection in a luminex 100 suspension array system. the assay covers the nine most important bacterial and viral pathogens found in danish meningitis patients. the microorganisms include neisseria meningitidis, streptococcus pneumoniae, escherichia coli, staphylococcus aureus, listeria monocytogenes, streptococcus agalactiae, herpes simplex virus types 1 and 2, and varicella-zoster virus. the study was based on 1,187 samples ...	2009	19193844
hazard analysis of listeria monocytogenes contaminations in processing of salted roe from walleye pollock (theragra chalcogramma) in hokkaido, japan.	hazard analysis of listeria monocytogenes contamination during processing of salted walleye pollock (theragra chalcogramma) roe was performed for a seafood plant in japan from december 2005 to february 2006. as a result, l. monocytogenes number was detected on the pallet used for transport of barrels in the salting process and one of the rollers of the roller conveyor, which rotates while in contact with the bottoms of the barrels, but was not detected in any raw materials, interim products or f ...	2009	19194081
high initial frequency of tcr-transgenic cd8 t cells alters inflammation and pathogen clearance without affecting memory t cell function.	in adoptive transfer experiments, the initial frequency of naïve tcr-transgenic t cells impacts cd8 t cell phenotype after acute infections. the exact reasons for the observed changes, however, are unclear and it is unknown whether alterations in phenotype translate into impaired memory t cell function as well. here we perform in vivo comparisons of effector and memory cd8 t cells generated from high or low numbers of naïve precursors. we show that high numbers of adoptively transferred t cells ...	2009	19195704
[neonatal meningitis due to listeria monocytogenes after 3 weeks of maternal treatment during pregnancy].	we report the case of a pregnant woman with listeriosis at 26 gestational weeks followed by premature labor at 30 gestational weeks. bacterial meningitis was suspected in the neonate with ventriculitis on sonography, a high level of protein in the cerebrospinal fluid (csf), and an identified specific bacterial genome of listeria monocytogenes (pcr 16s rdna and sequencing and specific amplification of l. monocytogenes hly gene) in csf. neonatal meningitis was complicated with cerebral venous sinu ...	2009	19195853
molecular characterization of the arginine deiminase system in listeria monocytogenes: regulation and role in acid tolerance.	the capacity of listeria monocytogenes to withstand low ph is important for growth in low-ph foods, successful passage through the gastric barrier and survival within the macrophage phagosome. the ability of this pathogen to survive and adapt to acidic conditions is therefore predicted to play a significant role in the infectious cycle. in silico analysis of the l. monocytogenes genome revealed the presence of putative arginine deiminase (adi) genes, which have been shown to play a role in the a ...	2009	19196274
changes in barotolerance, thermotolerance, and cellular morphology throughout the life cycle of listeria monocytogenes.	changes in barotolerance, thermotolerance, and cellular morphology throughout the life cycle of listeria monocytogenes were investigated. for part 1 of this analysis, l. monocytogenes atcc 19115 was grown to log, stationary, death, and long-term-survival phases at 35 degrees c in tryptic soy broth with yeast extract (tsbye). cells were diluted in whole milk that had been subjected to ultrahigh temperatures (uht whole milk) and then high-pressure processed (hpp) at 400 mpa for 180 s or thermally ...	2009	19168646
spontaneous fermentation of traditional sago starch in papua new guinea.	sago starch is an important dietary carbohydrate in lowland papua new guinea (png). an investigation was conducted to determine whether microbes play a role in its preservation using traditional methods. in 12 stored sago samples collected from png villages, lactic acid bacteria (lab) were present (> or = 3.6 x 10(4)cfu/g) and ph ranged from 6.8 to 4.2. acetic and propionic acids were detected in all samples, while butyric, lactic and valeric acids were present in six or more. in freshly prepare ...	2009	19171254
effects of gamma-irradiation on listeria monocytogenes population, colour, texture and sensory properties of feta cheese during cold storage.	feta, a white brine cheese, was produced and contaminated with listeria monocytogenes. contamination occurred either at the beginning (pre-process contamination) or at the end of feta manufacturing (post-process contamination). in the first case the milk was contaminated with 10(3) cfu/ml, and 2 months later, in the final product, the l. monocytogenes population was approximately 10(5) cfu/g. in the second case, the brine (nacl, 7% w/v), in which the feta was packaged, was contaminated with 10(3 ...	2009	19171257
contributions to selected phenotypic characteristics of large species- and lineage-specific genomic regions in listeria monocytogenes.	we hypothesized that genomic regions specific to listeria monocytogenes or selected l. monocytogenes strains may contribute to virulence and phenotypic differences among the strains. a whole genome alignment of two completed l. monocytogenes genomes and the one completed listeria innocua genome initially identified 28 genomic regions of difference (rd) > 4 kb that were found in one or both l. monocytogenes genomes, but absent from the non-pathogenic l. innocua. in silico analyses using an additi ...	2009	19171265
a comparison between e-beam irradiation and high pressure treatment for cold-smoked salmon sanitation: microbiological aspects.	the effectiveness of electron beam irradiation and high pressure treatment for the sanitation of cold-smoked salmon from two points of view, microbial safety and shelf-life extension, was compared. from the response of l. monocytogenes inia h66a to irradiation, a d value of 0.51 kgy was calculated. for samples stored at 5 degrees c, 1.5 kgy would be sufficient to attain a food safety objective (fso) of 2 log(10)cfu/g l. monocytogenes for a 35-day shelf-life, whereas 3 kgy would be needed in the ...	2009	19171266
prevalence and risk factors for bacterial food-borne zoonotic hazards in slaughter pigs: a review.	the hygiene package and regulation ec-2160/2003 require information flow from farm to slaughterhouse to enhance european consumers protection in a 'farm to fork' approach. this obligation especially concerns food-borne zoonotic hazards transmitted to humans through pork consumption, such as thermophilic campylobacter spp., listeria monocytogenes, salmonella enterica and yersinia enterocolitica. prevalence estimates of these four hazards are affected by the sampling strategy and diagnostic proced ...	2009	19175574
multiple mechanisms contribute to the robust rapid gamma interferon response by cd8+ t cells during listeria monocytogenes infection.	a subset of cd8+ t cells can rapidly secrete gamma interferon (ifn-gamma) in an antigen-independent and interleukin-12 (il-12)- and il-18-dependent manner within 16 h of infection with the intracellular bacterial pathogen listeria monocytogenes. this rapid ifn-gamma response is robust enough to be detected directly ex vivo and is not observed following infection with intracellular bacterial pathogens that remain sequestered within host cell vacuoles. we demonstrate here that three distinct pathw ...	2009	19179413
a novel il-17-dependent mechanism of cross protection: respiratory infection with mycoplasma protects against a secondary listeria infection.	immune responses to pathogens occur within the context of current and previous infections. cross protection refers to the phenomena where infection with a particular pathogen provides enhanced resistance to a subsequent unrelated pathogen in an antigen-independent manner. proposed mechanisms of antigen-independent cross protection have involved the secretion of ifn-gamma, which activates macrophages, thus providing enhanced innate immunity against the secondary viral or bacterial pathogen. here ...	2009	19180464
both thiamine uptake and biosynthesis of thiamine precursors are required for intracellular replication of listeria monocytogenes.	thiamine pyrophosphate is an essential cofactor involved in central metabolism and amino acid biosynthesis and is derived from thiamine (vitamin b(1)). the extent to which this metabolite is available to bacterial pathogens replicating within host cells is still little understood. growth studies using modified minimal welshimer's broth (mmwb) supplemented with thiamine or the thiamine precursor hydroxymethylpyrimidine (hmp) showed that listeria monocytogenes, in agreement with bioinformatic pred ...	2009	19181806
generation of branched-chain fatty acids through lipoate-dependent metabolism facilitates intracellular growth of listeria monocytogenes.	the gram-positive bacterial pathogen listeria monocytogenes has evolved mechanisms to rapidly replicate in the host cytosol, implying efficient utilization of host-derived nutrients. however, the contribution of host nutrient scavenging versus that of bacterial biosynthesis toward rapid intracellular growth remains unclear. nutrients that contribute to growth of l. monocytogenes include branched-chain fatty acids (bcfas), amino acids, and other metabolic intermediates generated from acyl-coenzym ...	2009	19181817
stress- and growth rate-related differences between plate count and real-time pcr data during growth of listeria monocytogenes.	to assess the overestimation of bacterial cell counts in real-time pcr in relation to stress and growth phase, four different strains of l. monocytogenes were exposed to combinations of osmotic stress (0.5 to 8% [vol/vol] nacl) and acid stress (ph 5 to 7) in a culture model at a growth temperature of 10 degrees c or were grown under optimal conditions. growth curves obtained from real-time pcr, optical density, and viable count data were compared. as expected, optical density data revealed entir ...	2009	19181831
insights into structure-activity relationships in the c-terminal region of divercin v41, a class iia bacteriocin with high-level antilisterial activity.	divercin v41 (dvnv41) is a class iia bacteriocin with potent antilisterial activity isolated from carnobacterium divergens v41. previously, we expressed from a synthetic gene, in escherichia coli origami, a recombinant dvnv41 designated dvnrv41, which possesses four additional amino acids (amdp) in the n-terminal region that result from enzymatic cleavage and retains the initial dvnv41 activity. to unravel the relationship between the structure of dvnrv41 and its particularly elevated activity, ...	2009	19181835
complete but curtailed t-cell response to very low-affinity antigen.	after an infection, t cells that carry the cd8 marker are activated and undergo a characteristic kinetic sequence of rapid expansion, subsequent contraction and formation of memory cells. the pool of naive t-cell clones is diverse and contains cells bearing t-cell antigen receptors (tcrs) that differ in their affinity for the same antigen. how these differences in affinity affect the function and the response kinetics of individual t-cell clones was previously unknown. here we show that during t ...	2009	19182777
in vitro and in vivo efficacies of amlodipine against listeria monocytogenes.	listeria monocytogenes causes suppurative gastritis in balb/c mice. we investigated the effect of the antihypertensive drug amlodipine (aml) on the growth of l. monocytogenes in vitro and in vivo. aml showed noteworthy inhibitory action (minimum inhibitory concentration, mic(90) 32 microg/ml) against listeria strains and demonstrated cidal (minimum bactericidal concentration, mbc 64 microg/ml) activity. aml administered orally at 2.5 microg/g in female balb/c mice for 7 days, commencing 4 days b ...	2009	19184140
bio-mimetic surface engineering of plasmid-loaded nanoparticles for active intracellular trafficking by actin comet-tail motility.	intracellular transport after endosomal escape presents one of the major barriers for efficient non-viral gene delivery because plasmid dna and synthetic nanoparticulate carriers suffer from significantly restricted diffusion in the cytoplasm. we postulate that forces generated by actin polymerization, a mechanism used by several bacterial pathogens such as listeria monocytogenes, can be harnessed to propel nanoparticles within the cytoplasm and thereby overcome diffusional limitations associate ...	2009	19046764
screening of surface properties and antagonistic substances production by lactic acid bacteria isolated from the mammary gland of healthy and mastitic cows.	bovine mastitis (bm) is a costly disease in dairy cattle production. the prevention and treatment of mastitis is performed by applying antimicrobial products that negatively affect milk quality. in the last years, the use of probiotic microorganisms to prevent infections in humans and animals has being aggressively studied. samples from teat canal and milk (foremilk and stripping) were taken from healthy and mastitic mammary quarters. a screening of the surface properties and antagonistic substa ...	2009	19041199
rapid detection of listeria monocytogenes in food using culture enrichment combined with real-time pcr.	a rapid method for the detection of listeria monocytogenes in foods combining culture enrichment and real-time pcr was compared to the iso 11290-1 standard method. the culture enrichment component of the rapid method is based on the iso standard and includes 24h incubation in half-fraser broth, 4h incubation in fraser broth followed by dna extraction and real-time pcr detection of the ssra gene of l. monocytogenes. an internal amplification control, which is co-amplified with the same primers as ...	2009	19028297
smearing of soft cheese with enterococcus faecium whe 81, a multi-bacteriocin producer, against listeria monocytogenes.	enterococcus faecium whe 81, a multi-bacteriocin producer, was tested for its antimicrobial activity on listeria monocytogenes in munster cheese, a red smear soft cheese. the naturally delayed and superficial contamination of this type of cheese allowed the use of e. faecium whe 81 at the beginning of the ripening as a surface culture. a brine solution inoculated at 10(5)cfu of e. faecium whe 81 per ml was sprayed on the cheese surface during the first smearing operation. on day 7, smearing of c ...	2009	19028299
poor detection of low-virulence field strains of l. monocytogenes is related to selective agents in selective media and is unrelated to prfa.	we have previously shown a relationship between the virulence level of listeria monocytogenes strains and their detection on palcam medium. to account for the fact that only 40% of low-virulence field strains of l. monocytogenes were detected on palcam medium compared to 92% on aloa medium, the detection of virulent and low-virulence strains on decomposed selective aloa and palcam media was compared. this showed that better detection of the strains was not explained by the growth factors added t ...	2009	19028300
fate of post-processing inoculated listeria monocytogenes on vacuum-packaged pepperoni stored at 4, 12 or 25 degrees c.	if present, listeria monocytogenes may not be eliminated during processing of pepperoni or may be introduced during peeling, slicing, or packaging. we evaluated the fate of the pathogen on sliced inoculated pepperoni during vacuum-packaged storage, and potential differences in survival among three types of inocula, including nonacid-adapted, acid-adapted and pepperoni extract-habituated cultures. commercial pepperoni (two replicates, three samples per treatment) was sliced and inoculated (3 to 4 ...	2009	19028309
kinetics of resuscitation and growth of l. monocytogenes as a tool to select appropriate enrichment conditions as a prior step to rapid detection methods.	rapid methods still rely on a prior (shortened) enrichment step before application. quantitative information is a prerequisite for understanding the resuscitation kinetics of the growth during the enrichment step. in this study various basal and newly introduced selective enrichment broths were evaluated. first, growth parameters (lambda, mu(max)) of both healthy and sub-lethally injured cells were determined. next, a selection of enrichment broths was compared for their capacity to support dete ...	2009	19028311
molecular characteristics and virulence potential of listeria monocytogenes isolates from chinese food systems.	in this study, we examined listeria monocytogenes isolates from chinese food sources in an attempt to gain further insights on the molecular characteristics and virulence potential of this important foodborne pathogen. of the 88 l. monocytogenes food isolates recovered, 42 (47.7%) were of serovars 1/2a or 3a; 23 (26.1%) of serovars 1/2b or 3b; 15 (17.0%) of 1/2c or 3c; 6 (6.8%) of serovars 4b, 4d or 4e; and 2 (2.2%) of serovars 4a or 4c. in contrast to inlab locus conserved in all serovars, inte ...	2009	19028313
comparative proteomic analysis of listeria monocytogenes strains f2365 and egd.	listeria monocytogenes is a gram-positive, food-borne pathogen that causes disease in both humans and animals. there are three major genetic lineages of l. monocytogenes and 13 serovars. to further our understanding of the differences that exist between different genetic lineages/serovars of l. monocytogenes, we analyzed the global protein expression of the serotype 1/2a strain egd and the serotype 4b strain f2365 during early-stationary-phase growth at 37 degrees c. using multidimensional prote ...	2009	19028911
microbiological and toxicological effects of perla black bean (phaseolus vulgaris l.) extracts: in vitro and in vivo studies.	we investigated the microbiological and toxicological effects of three perla black bean extracts on the growth and culture of selected pathogenic microorganisms, the toxicity over vero cell lines and an in vivo rat model. three different solvents were used to obtain perla black bean extracts. all three perla black bean extracts were tested for antibacterial and antiparasitic activity and further analysed for intrinsic cytotoxicity (ic(50)). methanol perla black bean extract was used for acute to ...	2009	19053992
fine-tuning the safety and immunogenicity of listeria monocytogenes-based neonatal vaccine platforms.	we have developed virulence-attenuated strains of listeria monocytogenes (lm) that can be used as safe yet effective vaccine carriers for neonatal vaccination. here we compare the vaccine efficacy of lm based vaccine carrier candidates after only a single immunization in murine neonates and adults: lm delta(trps acta) based strains that express and secrete multiple copies of the model antigen ovalbumin (ova) either under the control of a phagosomal (p(hly)) or cytosolic (p(acta))-driven listeria ...	2009	19059297
rapid recruitment of innate immunity regulates variation of intracellular pathogen resistance in drosophila.	genetic variation in susceptibility to pathogens is a central concern both to medicine and agriculture and to the evolution of animals. here, we have investigated the link between such natural genetic variation and the immune response in wild-type drosophila melanogaster, a major model organism for immunological research. we found that within nine wild-type strains, different drosophila genotypes show wide-ranging variation in their ability to survive infection from the pathogenic bacteria liste ...	2009	19061858
inactivation of escherichia coli, listeria monocytogenes and yersinia enterocolitica in fermented sausages during maturation/storage.	the purpose of this study was to evaluate maturation and storage conditions as a way to increase the safety of non-heat treated fermented sausages. the specific objectives were to investigate the effects of storage time and temperature on the levels of escherichia coli, listeria monocytogenes and yersinia enterocolitica in fermented sausages and in broth, and to validate how well the broth experiments and some published models can predict inactivation in sausage. one strain each of e. coli, l. m ...	2009	19064299
necrotizing fasciitis due to listeria monocytogenes.		2009	19067624
prevalence of listeria in chinese food products from 13 provinces between 2000 and 2007 and virulence characterization of listeria monocytogenes isolates.	listeriosis is a severe disease with high mortality rate, especially in immunosuppressed individuals. the causative organism listeria monocytogenes is primarily transmitted to humans through contaminated foods. to gain an understanding of the prevalence of listeria in chinese food products, we reviewed relevant papers from journals published in china from 2000 to 2007. the average recovery rate of listeria spp. was 3.7% (0.1-7.7%) in all food categories in 13 provinces, with raw meat being the l ...	2009	19072082
chronic prosthetic joint infection caused by listeria monocytogenes.	we report what is to the best of our knowledge the first case of persistent human listeriosis. a housewife underwent excision of a leiomyosarcoma and implantation of a prosthetic knee device. infection of the device with listeria monocytogenes occurred and persisted for 2 years. despite having an allergy to ampicillin, the patient was cured solely by antibiotics and without surgery.	2009	19074666
comparison of three listeria monocytogenes strains in a guinea-pig model simulating food-borne exposure.	three different listeria monocytogenes strains, lo28 (a laboratory strain with truncated inla), 4446 (a clinical isolate) and 7291 (a food isolate), were compared in a guinea-pig model designed to mimic food-borne exposure. the objectives were (1) to verify the applicability of the animal model for distinguishing between listeria with different virulence properties and (2) to explore whether it was possible to reduce the required number of animals by dosing with mixed cultures instead of monocul ...	2009	19076231
signals triggered by a bacterial pore-forming toxin contribute to toll-like receptor redundancy in gram-positive bacterial recognition.	toll-like receptor (tlr) 2 is the principal recognition receptor for gram-positive microbes. however, in some gram-positive bacterial infections, tlr2 is dispensable. one of the outstanding questions regarding host-bacteria interactions is why tlr2 is essential in some infections but dispensable in others.	2009	19032107
subversion of antimicrobial calprotectin (s100a8/s100a9 complex) in the cytoplasm of tr146 epithelial cells after invasion by listeria monocytogenes.	expressed by squamous mucosal keratinocytes, calprotectin is a complex of two ef-hand calcium-binding proteins of the s100 subfamily (s100a8 and s100a9) with significant antimicrobial activity. calprotectin-expressing cells resist invasion by porphyromonas gingivalis, listeria monocytogenes, and salmonella enterica serovar typhimurium (s. typhimurium). to understand the interactions between calprotectin and invasive bacteria, we studied the distribution of calprotectin in the cytoplasm of tr146 ...	2009	19079333
the listeria monocytogenes sortase-b recognizes varied amino acids at position 2 of the sorting motif.	sortases are bacterial enzymes that anchor surface proteins covalently to the peptidoglycan upon cleavage of a motif located at their c-terminal end. motifs recognized by sortases of the class-b (srtb) are defined by the consensus sequence np(q/k)(t/s)(n/g/s)(d/a). evidence supporting this consensus is limited to isdc of staphylococcus aureus and bacillus anthracis, cleaved at motifs npqtn and npktg, respectively. in listeria monocytogenes, strb has two substrates, lmo2185 and lmo2186, containin ...	2009	19129190
the cellular niche of listeria monocytogenes infection changes rapidly in the spleen.	the spleen is an important organ for the host response to systemic bacterial infections. many cell types and cell surface receptors have been shown to play role in the capture and control of bacteria, yet these are often studied individually and a coherent picture has yet to emerge of how various phagocytes collaborate to control bacterial infection. we analyzed the cellular distribution of listeria monocytogenes (lm) in situ during the early phase of infection. using an immunohistochemistry app ...	2009	19130474
foci of listeria monocytogenes persist in the bone marrow.	murine listeriosis is one of the most comprehensive and well-studied models of infection, and listeria monocytogenes has provided seminal information regarding bacterial pathogenesis. however, many aspects of the mouse model remain poorly understood, including carrier states and chronic colonization which represent important features of the spectrum of host-pathogen interaction. bone marrow has recently been shown to harbor l. monocytogenes, which spreads from this location to the central nervou ...	2009	19132117
therapeutic index of gramicidin s is strongly modulated by d-phenylalanine analogues at the beta-turn.	analogues of the cationic antimicrobial peptide gramicidin s (gs), cyclo(val-orn-leu-d-phe-pro)2, with d-phe residues replaced by different (restricted mobility, mostly) surrogates have been synthesized and used in sar studies against several pathogenic bacteria. while all d-phe substitutions are shown by nmr to preserve the overall beta-sheet conformation, they entail subtle structural alterations that lead to significant modifications in biological activity. in particular, the analogue incorpo ...	2009	19132829
faecal shedding and strain diversity of listeria monocytogenes in healthy ruminants and swine in northern spain.	listeria monocytogenes is among the most important foodborne bacterial pathogens due to the high mortality rate and severity of the infection. l. monocytogenes is a ubiquitous organism occasionally present in the intestinal tract of various animal species and faecal shedding by asymptomatically infected livestock poses a risk for contamination of farm environments and raw food at the pre-harvest stages. the aim of this study was to determine the prevalence and strain diversity of l. monocytogene ...	2009	19133125
cd40-cd40l cross-talk integrates strong antigenic signals and microbial stimuli to induce development of il-17-producing cd4+ t cells.	il-17-producing cd4(+) t cells have been recognized as key players in organ-related autoimmune disease; however, the parameters that govern their development are yet to be elucidated fully. by using both in vivo and in vitro systems, we have investigated the role of antigen dose, pathogen-associated molecular patterns, and cd40-cd40 ligand (cd40l) cross-talk in th17 differentiation. we found that the strength of antigenic stimulation critically influenced the extent of th17 differentiation, beca ...	2009	19136631
hierarchical generalized linear models for multiple quantitative trait locus mapping.	we develop hierarchical generalized linear models and computationally efficient algorithms for genomewide analysis of quantitative trait loci (qtl) for various types of phenotypes in experimental crosses. the proposed models can fit a large number of effects, including covariates, main effects of numerous loci, and gene-gene (epistasis) and gene-environment (g x e) interactions. the key to the approach is the use of continuous prior distribution on coefficients that favors sparseness in the fitt ...	2009	19139143
interleukin-17 in host defence against bacterial, mycobacterial and fungal pathogens.	the mammalian immune system is intricately regulated, allowing for potent pathogen-specific immunity to be rapidly activated in response to infection with a broad and diverse array of potential pathogens. as a result of their ability to differentiate into distinct effector lineages, cd4 t cells significantly contribute to pathogen-specific adaptive immune responses. through the production of effector cytokines, cd4 t helper (th) cells orchestrate the precise mobilization of specific immune cells ...	2009	19125888
[expression of cytokines in murine bmdcs induced by recombinant e.coli llo/ova via tlr4 and nod1 receptors].	to investigate the relationship between the activation of pattern recognition receptors and the cytokines expression of dendritic cells.	2009	19126379
recombinant attenuated listeria monocytogenes vaccine expressing francisella tularensis iglc induces protection in mice against aerosolized type a f. tularensis.	fransicella tularensis, the causative agent of tularemia, is in the top category (category a) of potential agents of bioterrorism. to develop a safer vaccine against aerosolized f. tularensis, we have employed an attenuated listeria monocytogenes, which shares with f. tularensis an intracellular and extraphagosomal lifestyle, as a delivery vehicle for f. tularensis antigens. we constructed recombinant l. monocytogenes (rlm) vaccines stably expressing seven f. tularensis proteins including iglc ( ...	2009	19126421
toll-like receptors 2 and 5 in human gingival epithelial cells co-operate with t-cell cytokine interleukin-17.	periodontitis begins as the result of perturbation of the gingival epithelial cells caused by subgingival bacteria interacting with the epithelial cells via pattern recognition receptors. toll-like receptors (tlrs) have been shown to play an important role in the recognition of periodontal pathogens so we have studied the interaction of tlr ligands with tlr2 and tlr5 for cytokine production in the cultures of gingival epithelial cells.	2009	19121068
calprotectin s100a9 calcium-binding loops i and ii are essential for keratinocyte resistance to bacterial invasion.	epithelial cells expressing calprotectin, a heterodimer of s100a8 and s100a9 proteins, are more resistant to bacterial invasion. to determine structural motifs that affect resistance to bacterial invasion, mutations were constructed in s100a9 targeting the calcium-binding loops i and ii (e36q, e78q, e36q,e78q) and the c terminus (s100a9(1-99) and s100a9(1-112)), which contains putative antimicrobial zinc-binding and phosphorylation sites. the s100a8 and mutated s100a9 encoding plasmids were tran ...	2009	19122197
fatal mesenteric lymphadenitis in cattle caused by listeria monocytogenes.		2009	19122218
a pivotal role for the response regulator degu in controlling multicellular behaviour.	bacteria control multicellular behavioural responses, including biofilm formation and swarming motility, by integrating environmental cues through a complex regulatory network. heterogeneous gene expression within an otherwise isogenic cell population that allows for differentiation of cell fate is an intriguing phenomenon that adds to the complexity of multicellular behaviour. this review focuses on recent data about how degu, a pleiotropic response regulator, co-ordinates multicellular behavio ...	2009	19118340
phage-mediated intergeneric transfer of toxin genes.	because bacteriophages generally parasitize only closely related bacteria, it is assumed that phage-mediated genetic exchange occurs primarily within species. here we report that staphylococcal pathogenenicity islands, containing superantigen genes, and other mobile elements transferred to listeria monocytogenes at the same high frequencies as they transfer within staphylococcus aureus. several staphylococcal phages transduced l. monocytogenes but could not form plaques. in an experiment modelin ...	2009	19119236
selective detection of live bacteria combining propidium monoazide sample treatment with microarray technology.	the use of dna-based molecular detection tools for bacterial diagnostics is hampered by the inability to distinguish signals originating from live and dead cells. the detection of live cells is typically most relevant in molecular diagnostics. dna-intercalating dyes like ethidium monoazide and propidium monoazide (pma) offer a possibility to selectively remove cells with compromised cell membranes from the analysis. once these dyes enter a cell, they bind to dna and can be covalently crosslinked ...	2009	19103234
antilisterial activities of polyphenol-rich extracts of grapes and vinification byproducts.	the quantitation of the main polyphenols and the assessment of the total polyphenolic content (tpc) in polyphenol-rich extracts of grape berries and vinification byproducts, obtained from vitis vinifera cultivars of the greek islands, are presented. the results indicated that seed extracts contain high concentrations of flavan-3-ols and their derivatives, whereas pomace and stem extracts consist of significant amounts of flavonoids, stilbenes, and phenolic acids. in particular, stemsa scarcely s ...	2009	19105651
sensitive isothermal detection of nucleic-acid sequence by primer generation-rolling circle amplification.	a simple isothermal nucleic-acid amplification reaction, primer generation-rolling circle amplification (pg-rca), was developed to detect specific nucleic-acid sequences of sample dna. this amplification method is achievable at a constant temperature (e.g. 60 degrees c) simply by mixing circular single-stranded dna probe, dna polymerase and nicking enzyme. unlike conventional nucleic-acid amplification reactions such as polymerase chain reaction (pcr), this reaction does not require exogenous pr ...	2009	19106144
pyrin and asc co-localize to cellular sites that are rich in polymerizing actin.	familial mediterranean fever (fmf) is an autoinflammatory disease caused by mutations in the mefv locus, which encodes the protein pyrin. while it is known that pyrin is expressed in myeloid cells and several fibroblastic cell types, the exact function of pyrin in these cells and the mechanism underlying the pathological effect of pyrin mutations have yet to be revealed. here, we document that in migrating human monocytes, pyrin protein is dramatically polarized at the leading edge, where it co- ...	2009	19109554
b7-h4-deficient mice display augmented neutrophil-mediated innate immunity.	b7-h4 is an immunoglobulin superfamily molecule and shown to be inhibitory for t-cell responses. to explore physiologic roles of b7-h4, we created b7-h4-deficient (ko) mice by genetic targeting. b7-h4ko mice are healthy and their t- and b-cell responses to polyclonal antigens are in normal range. however, b7-h4ko mice are more resistant to infection by listeria monocytogenes than their littermates. within 3 days after infection, bacterial colonies in livers and spleens are significantly lower th ...	2009	19109567
molecular ecology of listeria monocytogenes: evidence for a reservoir in milking equipment on a dairy farm.	a longitudinal study aimed to detect listeria monocytogenes on a new york state dairy farm was conducted between february 2004 and july 2007. fecal samples were collected every 6 months from all lactating cows. approximately 20 environmental samples were obtained every 3 months. bulk tank milk samples and in-line milk filter samples were obtained weekly. samples from milking equipment and the milking parlor environment were obtained in may 2007. fifty-one of 715 fecal samples (7.1%) and 22 of 30 ...	2009	19114514
elevated non-specific immunity and normal listeria clearance in young and old vitamin d receptor knockout mice.	1,25-dihydroxyvitamin d(3) [1,25(oh)(2)d(3)] and the vitamin d receptor (vdr) are important regulators of autoimmunity. the effect of the vdr on the ability of mice to fight a primary or secondary infection has not been determined. young and old vdr knockout (ko) mice were able to clear both primary and secondary infections with listeria monocytogenes. however, the kinetics of clearance was somewhat delayed in the absence of the vdr. memory t cell development was not different in young vdr ko an ...	2009	19088060
clinical characteristics and outcomes of the meningitides in systemic lupus erythematosus.	the meningitides are rare but well-identified complications in patients with systemic lupus erythematosus (sle).	2009	19092250