| influence of acid stress on survival, expression of virulence genes and invasion capacity into caco-2 cells of listeria monocytogenes strains of different origins. | the influence of food-related acid stress on the virulence capacity of listeria monocytogenes was evaluated. the survival of acid-adapted and non-adapted l. monocytogenes cells during exposure to lethal concentrations of acetic acid was monitored. also the effect of sublethal acid stress exposure on the expression levels of several virulence genes and on the capacity to invade caco-2 cells was analyzed. acid-adapted and non-adapted cells showed different acid tolerance response (atr) patterns. o ... | 2009 | 19403190 |
| nk-cell-mediated killing of target cells triggers robust antigen-specific t-cell-mediated and humoral responses. | previous work showed that administration of antigen-expressing apoptotic cells in vivo results in antigen-specific cd8+ t-cell responses independent of toll-like receptor signaling. we report here that natural killer (nk) cells can serve a function directly upstream of this pathway and initiate robust adaptive immune responses via killing of antigen-expressing target cells. this pathway is highly sensitive, in that administration of as few as 10(4) target cells induced detectable antigen-specifi ... | 2009 | 19406986 |
| use of a phospholipase-c assay, in vivo pathogenicity assays and pcr in assessing the virulence of listeria spp. | listeria spp. was isolated from 19.8% of animals with a history of reproductive disorders. a total of 333 faecal, genital swab and blood samples from 111 animals (cattle, buffaloes, sheep and goats) were subjected to pcr to detect virulence-associated genes (prfa, plca, hlya, acta and iap) and pathogenicity testing by the phosphatidylinositol phospholipase-c (pi-plc) assay, and by mouse and chick embryo inoculation. one isolate of listeria ivanovii recovered from a genital swab from a sheep was ... | 2010 | 19409824 |
| listeria monocytogenes isolated from vegetable salads sold at supermarkets in santiago, chile: prevalence and strain characterization. | between 2000 and 2005, 717 samples of three types of salads were analysed for listeria monocytogenes in santiago, chile in order to provide information to chilean health authorities on the presence of the pathogen in vegetable salad samples and to ascertain the risk of these products for consumers. l. monocytogenes isolates were found in 88 out of 347 (25.4%) samples of frozen vegetable salads and in 22 out of 216 (10.2%) freshly supermarkets prepared, cooked or raw ready-to-eat vegetable salads ... | 2009 | 19410317 |
| response of listeria monocytogenes to disinfection stress at the single-cell and population levels as monitored by intracellular ph measurements and viable-cell counts. | listeria monocytogenes has a remarkable ability to survive and persist in food production environments. the purpose of the present study was to determine if cells in a population of l. monocytogenes differ in sensitivity to disinfection agents as this could be a factor explaining persistence of the bacterium. in situ analyses of listeria monocytogenes single cells were performed during exposure to different concentrations of the disinfectant incimaxx des to study a possible population subdivisio ... | 2009 | 19411424 |
| adaptation and cross-adaptation of listeria monocytogenes and salmonella enterica to poultry decontaminants. | information on the potential for acquired reduced susceptibility of bacteria to poultry decontaminants occurring is lacking. minimal inhibitory concentrations (mics) were established for assessing the initial susceptibility and the adaptative and cross-adaptative responses of four bacterial strains (listeria monocytogenes serovar l/2a, l. monocytogenes serovar 4b, salmonella enterica serotype typhimurium, and s. enterica serotype enteritidis) to four poultry decontaminants (trisodium phosphate, ... | 2009 | 19412596 |
| evaluation of iso enrichment real-time pcr methods with internal amplification control for detection of listeria monocytogenes and salmonella enterica in fresh fruit and vegetables. | to provide with a quick method for qualitative detection, in less than three days, of salmonella enterica and listeria monocytogenes in fresh fruit and vegetables. | 2009 | 19413765 |
| critical roles of nk and cd8+ t cells in central nervous system listeriosis. | listeria monocytogenes (lm) causes a life-threatening infectious disease affecting the brain of humans and domestic animals. unfortunately, no adequate murine models for cns listeriosis exist. using intraparenchymal injection, we have established a new murine model for cns listeriosis. injection of a small volume of bacterial suspension limits the bacteria to the brain parenchyma with no leakage into the ventricular system. this new method enabled us to investigate the progression of and recover ... | 2009 | 19414789 |
| growth parameters of escherichia coli o157:h7, salmonella spp., listeria monocytogenes, and aerobic mesophilic bacteria of apple cider amended with nisin-edta. | the effect of nisin (0 or 300 iu/ml), ethylenediamine tetraacetic acid (edta, 20 mm), and nisin (300 iu)-edta (20 mm) on growth parameters, including lag period (lp) and generation time, of escherichia coli o157:h7, listeria monocytogenes, and salmonella spp. in the presence or absence of aerobic mesophilic bacteria of apple cider during storage at 5 degrees c for up to 16 days or 23 degrees c for 16 h was investigated. the growth data were analyzed and fitted to the modified gompertz model. the ... | 2009 | 19415973 |
| candida albicans internalization by host cells is mediated by a clathrin-dependent mechanism. | candida albicans is a major cause of oropharyngeal, vulvovaginal and haematogenously disseminated candidiasis. endocytosis of c. albicans hyphae by host cells is a prerequisite for tissue invasion. this internalization involves interactions between the fungal invasin als3 and host e- or n-cadherin. als3 shares some structural similarity with inla, a major invasion protein of the bacterium listeria monocytogenes. inla mediates entry of l. monocytogenes into host cells through binding to e-cadheri ... | 2009 | 19416270 |
| engineering an artificial amoeba propelled by nanoparticle-triggered actin polymerization. | we have engineered an amoeba system combining nanofabricated inorganic materials with biological components, capable of propelling itself via actin polymerization. the nanofabricated materials have a mechanism similar to the locomotion of the listeria monocytogenes, food poisoning bacteria. the propulsive force generation utilizes nanoparticles made from nickel and gold functionalized with the listeria monocytogenes transmembrane protein, acta. these listeria-mimic nanoparticles were in concert ... | 2009 | 19417437 |
| [predisposing factors of community acquired bacterial meningitis (excluding neonates)]. | meningeal defects and primitive ent infections are known to promote pneumococcal meningitis. other risk factors can be identified in the occurrence of community acquired bacterial meningitis (cabm) and play a key role either in the frequency of this kind of infection, the type of bacteria concerned, the prognosis or the risk of recurrence. thus, epidural infiltrations are rarely responsible for staphylococcal or streptococcal meningitis. cochlear implants are also known to increase the risk of p ... | 2009 | 19419829 |
| the alternative sigma factor sigma(l) of l. monocytogenes promotes growth under diverse environmental stresses. | listeria monocytogenes are important foodborne pathogens that can cause outbreaks of serious human disease. these organisms frequently colonize and proliferate on preserved food products despite exposure to stress conditions induced by low storage temperatures, inclusion of organic acid-based preservatives, and high osmolarity. to assess alternative sigma factor sigma(l) contributions to such stress resistance of l. monocytogenes, quantitative rt-pcr assays and sigl gene deletion mutagenesis wer ... | 2009 | 19422306 |
| inhibition of listeria monocytogenes by acetate, benzoate and sorbate: weak acid tolerance is not influenced by the glutamate decarboxylase system. | weak acids are widely used by the food industry to prevent spoilage and to inhibit the growth of pathogenic micro-organisms. in this study the inhibitory effects of three commonly used weak acids, acetic acid, benzoic acid and sorbic acid, on the growth of listeria monocytogenes were investigated. | 2009 | 19422474 |
| antagonistic effect of toll-like receptor signaling and bacterial infections on transplantation tolerance. | the induction of donor-specific tolerance remains a major goal in the field of transplantation immunology. therapies that target costimulatory molecules can induce tolerance to heart and pancreatic islet allografts in mouse models, but fail to do so after transplantation of skin or intestinal allografts. we have proposed that organs colonized by commensal bacteria such as skin, lung, and intestine may be resistant to such therapies as a result of bacterial translocation at the time of transplant ... | 2009 | 19424015 |
| hyperglycemia in bacterial meningitis: a prospective cohort study. | hyperglycemia has been associated with unfavorable outcome in several disorders, but few data are available in bacterial meningitis. we assessed the incidence and significance of hyperglycemia in adults with bacterial meningitis. | 2009 | 19426501 |
| role of tripeptidyl peptidase ii in the processing of listeria monocytogenes-derived mhc class i-presented antigenic peptides. | the effective control of the infection of mice with the facultatively intracellular bacterium listeria monocytogenes requires cd8 t cells which recognize bacterial antigenic peptides presented in the context of host mhc class i molecules. it is generally accepted that bacterial antigens are processed by the proteasome, a proteolytic cytoplasmic multiprotein complex. we observed that presentation of the l. monocytogenes-derived cd8 t cell epitope llo 91-99 by infected cells can not be totally sup ... | 2009 | 19426827 |
| antimicrobial resistance of listeria monocytogenes isolated from dairy-based food products. | in this study listeria monocytogenes (l. monocytogenes) was isolated from three traditionally consumed lebanese dairy-based food products. one hundred and sixty four samples (45 samples of baladi cheese, 36 samples of shankleesh and 83 of kishk) were collected from the bekaa valley in the northeast region of lebanon. suspected listeria colonies were selected and initially identified by using standard biochemical tests. initial identification of the positive l. monocytogenes colonies was confirme ... | 2009 | 19427675 |
| [presumptive bacterial meningitis in adults: initial antimicrobial therapy]. | csf sterilization should be obtained very rapidly to reduce both mortality and morbidity due to bacterial meningitis. thus, antibiotic treatment should be adapted to the suspected bacterium and administered as early as possible at high dosage with - if necessary - a loading dose and continuous perfusion. the rates of abnormal susceptibility to penicillin of streptococcus pneumoniae, neisseria meningitis and haemophilus influenzae are 37%, 30% and 12% respectively. thus, ceftriaxone or cefotaxim ... | 2009 | 19428207 |
| neutrophil activation induced by artinm: release of inflammatory mediators and enhancement of effector functions. | the d-mannose binding lectin artinm from artocarpus integrifolia, previously known as km+ and artocarpin, is considered a stimulant of th1-type immunity, which is able to confer resistance to some intracellular pathogens. in addition, artinm induces neutrophil migration by haptotaxis through simultaneous interactions of its carbohydrate recognition domains (crds) with glycans expressed on the extracellular matrix and the neutrophil surface. in the present study, we have expanded the characteriza ... | 2009 | 19428547 |
| genotypic versus phenotypic methods in the detection of listeria monocytogenes prosthetic joint infection. | a rare case of a severe prosthetic joint infection in a 71-year-old immunocompetent woman is presented. listeria monocytogenes was identified in two consecutive samples using broad-range pcr and sequencing, whereas cultivation remained negative for the first sample and streptococci of a non-group a streptococci, non-group b streptococci type were detected for the second one. this report demonstrates that the phenotypic approach may lead to misidentification of l. monocytogenes in a routine clini ... | 2009 | 19429762 |
| radical scavenging activity of the essential oil of silver fir (abies alba). | the essential oil of silver fir (abies alba) is known to help respiratory system and have easing and soothing effect for muscle. in the present study, we investigated the chemical composition, cytotoxicity and its biological activities of silver fir (abies alba) essential oil. the composition of the oil was analyzed by gc-ms and bornyl acetate (30.31%), camphene (19.81%), 3-carene (13.85%), tricyclene (12.90%), dl-limonene (7.50%), alpha-pinene (2.87%), caryophyllene (2.18%), beta-phellandrene ( ... | 2009 | 19430614 |
| involvement of cd44v6 in inlb-dependent listeria invasion. | listeria monocytogenes, a gram-positive bacterium, is the causative agent for the disease called listeriosis. this pathogen utilizes host cell surface proteins such as e-cadherin or c-met in order to invade eukaryotic cells. the invasion via c-met depends on the bacterial protein inlb that activates c-met phosphorylation and internalization mimicking in many regards hgf, the authentic c-met ligand. in this paper, we demonstrate that the activation of c-met induced by inlb is dependent on cd44v6, ... | 2009 | 19432801 |
| control of listeria monocytogenes on frankfurters by dipping in hops beta acids solutions. | hops beta acids (hba) are parts of hops flowers used in beer brewing and have shown antilisterial activity in bacteriological broth. the u.s. department of agriculture, food safety and inspection service has approved hba for use to control listeria monocytogenes on ready-to-eat meat products. this study evaluated the effects of hba as dipping solutions to control l. monocytogenes during storage of frankfurters. frankfurters (two replicates and three samples each) were inoculated (1.9 +/- 0.1 log ... | 2009 | 19435215 |
| molecular typing reveals frequent clustering among human isolates of listeria monocytogenes in italy. | in italy, the annual incidence of reported cases of listeriosis amounts in recent years (2004 to 2006) to 0.8 case per million inhabitants. our study is a subtyping analysis by serotyping, ribotyping, and pulsed-field gel electrophoresis analysis of 44 human isolates from apparently sporadic cases of infection in the lombardy region and in the province of florence, italy, in the years 1996 to 2007. based on the results of the different subtyping methods, 10 occasions were detected when strains o ... | 2009 | 19435242 |
| antibacterial protection by enterocin as-48 in sport and energy drinks with less acidic ph values. | the low ph and acid content found in sports and energy drinks are a matter of concern in dental health. raising the ph may solve this problem, but at the same time increase the risks of spoilage or presence of pathogenic bacteria. in the present study, commercial energy drinks were adjusted to ph 5.0 and challenged with listeria monocytogenes (drinks a to f), staphylococcus aureus, bacillus cereus, and bacillus licheniformis (drink a) during storage at 37 degrees c. l. monocytogenes was able to ... | 2009 | 19435243 |
| listeria monocytogenes delivery of hpv-16 major capsid protein l1 induces systemic and mucosal cell-mediated cd4+ and cd8+ t-cell responses after oral immunization. | neutralizing antibodies are thought to be required at mucosal surfaces to prevent human papillomavirus (hpv) transmission. however, the potential for cell-mediated immunity in mediating protection against hpv infection has not been well explored. we generated recombinant listeria monocytogenes (lm) constructs that secrete listeriolysin o (llo) fused with overlapping n-terminal (llo-l1(1-258)) or c-terminal (llo-l1(238-474)) fragments of hpv type 16 major capsid protein l1 (hpv-16-l1). oral immun ... | 2009 | 19435416 |
| intracellular bacterial vectors that induce cd8(+) t cells with similar cytolytic abilities but disparate memory phenotypes provide contrasting tumor protection. | induction of a functional cd8(+) t-cell response is the important criterion for cancer vaccines, and it is unclear whether acute or chronic live vectors are better suited for cancer antigen delivery. we have evaluated the tumor protective ability of two recombinant vectors, listeria monocytogenes (lm) and salmonella typhimurium (st), both expressing ovalbumin (ova). although both vectors induced a similar ova-specific cd8(+) t-cell response in the long term, lm-ova induced mainly central-phenoty ... | 2009 | 19435919 |
| validation of commercial processes for inactivation of escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes on the surface of whole-muscle turkey jerky. | three strips of turkey breast meat were separately inoculated with multistrain mixtures of escherichia coli o157:h7, salmonella typhimurium, or listeria monocytogenes and placed on the top, middle, and bottom levels of a loading rack. the strips on the rack were then loaded into a smokehouse and cooked-dried for either 2.5 or 3.5 h at 73.8 degrees c (165 degrees f) or 1.5 or 2.5 h at 82.2 degrees c (180 degrees f) with constant hickory smoking and without addition of humidity. cooking-drying mar ... | 2009 | 19439640 |
| interventions for control of salmonella: clearance of microbial growth from rubber picker fingers. | a study was conducted to determine if a surface material with antimicrobial properties combined with an effective disinfectant could achieve total clearance of bacterial contamination. before beginning the project, new rubber picker fingers collected from 3 processing facilities were tested for endogenous microflora. five species of bacteria common to soil and human handling were present: bacillus amyloliquefaciens, bacillus cereus/thuringiensis, staphylococcus epidermidis, staphylococcus homini ... | 2009 | 19439642 |
| modeling human listeriosis in natural and genetically engineered animals. | listeria monocytogenes causes listeriosis, a human foodborne infection leading to gastroenteritis, meningoencephalitis and maternofetal infections. inla and inlb, two l. monocytogenes surface proteins, interact with their respective receptors e-cadherin and met and mediate bacterial entry into human cultured cells. here, we present protocols for studying listeriosis in three complementary animal models: (i) the human e-cadherin (hecad) transgenic mouse line; (ii) the knock-in e16p mouse line; an ... | 2009 | 19444238 |
| [immunogenicity comparision of listeria monocytogenes inactivated by gamma-irradiation or traditional treatments]. | listeria monocytogenes (lm) is a gram-positive facultative intracellular pathogen that can cause animal and human listeriosis. in order to use killed lm in vaccination, we compared, in a mouse model, the immunogenicity of lm that were lethally inactivated by gamma-irradiation, traditional heat or formalin treatment. | 2009 | 19445186 |
| bacteriocin production by pediococcus pentosaceus isolated from marula (scerocarya birrea). | strain st44am, isolated from marula, was identified as pediococcus pentosaceus based on biochemical tests, sugar fermentation reactions (api 50chl), pcr with species-specific primers and 16s rdna sequencing. strain st44am produces a 6.5 kda class iia bacteriocin, active against lactic acid bacteria, escherichia coli, pseudomonas aeruginosa, klebsiella pneumoniae, listeria innocua, listeria ivanovii subsp. ivanovii and listeria monocytogenes. the peptide is inactivated by proteolytic enzymes, but ... | 2009 | 19446352 |
| recognition of at-rich dna binding sites by the mogr repressor. | the mogr transcriptional repressor of the intracellular pathogen listeria monocytogenes recognizes at-rich binding sites in promoters of flagellar genes to downregulate flagellar gene expression during infection. we describe here the 1.8 a resolution crystal structure of mogr bound to the recognition sequence 5' attttttaaaaaaat 3' present within the flaa promoter region. our structure shows that mogr binds as a dimer. each half-site is recognized in the major groove by a helix-turn-helix motif a ... | 2009 | 19446532 |
| gender differences in expression of the human caspase-12 long variant determines susceptibility to listeria monocytogenes infection. | inflammatory caspases are important effectors of innate immunity. caspase-12, of the inflammatory caspase subfamily, is expressed in all mammals tested to date, but has acquired deleterious mutation in humans. a single-nucleotide polymorphism introduces a premature stop codon in caspase-12 in the majority of the population. however, in 20% of african descendants, caspase-12 is expressed and sensitizes to infections and sepsis. here, we examined the modalities by which human caspase-12 confers su ... | 2009 | 19447924 |
| the listeria transcriptional landscape from saprophytism to virulence. | the bacterium listeria monocytogenes is ubiquitous in the environment and can lead to severe food-borne infections. it has recently emerged as a multifaceted model in pathogenesis. however, how this bacterium switches from a saprophyte to a pathogen is largely unknown. here, using tiling arrays and rnas from wild-type and mutant bacteria grown in vitro, ex vivo and in vivo, we have analysed the transcription of its entire genome. we provide the complete listeria operon map and have uncovered far ... | 2009 | 19448609 |
| the posttranslocation chaperone prsa2 contributes to multiple facets of listeria monocytogenes pathogenesis. | listeria monocytogenes is an intracellular bacterial pathogen whose virulence depends on the regulated expression of numerous secreted bacterial factors. as for other gram-positive bacteria, many proteins secreted by l. monocytogenes are translocated across the bacterial membrane in an unfolded state to the compartment existing between the membrane and the cell wall. this compartment presents a challenging environment for protein folding due to its high density of negative charge, high concentra ... | 2009 | 19451247 |
| infectious complications in patients receiving autologous cd34-selected hematopoietic stem cell transplantation for severe autoimmune diseases. | long-term analysis of infectious complication after high-dose immunosuppressive therapy with cd34-selected autologous hematopoietic stem cell transplantation for patients with severe autoimmune diseases (ad) was performed. theoretically, cd34 selection can reduce the risk of reinfusion of autoreactive lymphocytes. however, it is also associated with a significant reduction in t cells, natural killer cells, and monocytes, which in turn may compromise immune reconstitution, thereby increasing the ... | 2009 | 19453993 |
| expression of lap, a seca2-dependent secretory protein, is induced under anaerobic environment. | listeria adhesion protein (lap), an alcohol acetaldehyde dehydrogenase homolog (lmo1634) in listeria monocytogenes, promotes bacterial adhesion to intestinal epithelial cells in vitro. investigation of the effect of anaerobiosis, an intrinsic gastrointestinal condition, on lap expression and lap-mediated infection should elucidate its significance during intestinal infection. the influence of anaerobiosis on lap expression was determined by growing l. monocytogenes wild type (wt), and lap-defici ... | 2009 | 19454322 |
| identification of an ifn-gamma-producing neutrophil early in the response to listeria monocytogenes. | ifn-gamma plays a critical role during the immune response to infection with listeria monocytogenes. early in the innate response nk cells are thought to be a primary source of ifn-gamma; however, protection can be mediated by the presence of significant numbers of primed ifn-gamma-secreting cd8(+) t cells. in this report, we examined the early response to listeria and found that 18 h after infection spleens contain cd11b(+), gr-1(high), or ly6g(+) cells that produce significant ifn-gamma. morph ... | 2009 | 19454704 |
| genome-wide screen for listeria monocytogenes genes important for growth at high temperatures. | listeria monocytogenes is a gram-positive food-borne pathogen that is able to grow over a wide temperature range. although the class i and class iii heat-shock genes are known to play an important role in heat shock, information on genes that are essential for growth at high temperatures is scarce. to determine which genes are important for growth at high temperatures (42.5-43 degrees c), we performed a random insertion screening in l. monocytogenes, rendering 28 temperature-sensitive mutants. t ... | 2009 | 19456866 |
| recognition of salmonella typhimurium by immobilized phage p22 monolayers. | phages are promising alternatives to antibodies as the biorecognition element in a variety of biosensing applications. in this study, a monolayer of bacteriophage p22 whose tailspike proteins specifically recognize salmonella serotypes was covalently bound to glass substrates through a bifunctional cross linker 3-aminopropyltrimethoxysilane. the specific binding of salmonella typhimurium to the phage monolayer was studied by enzyme-linked immunosorbent assay and atomic force microscopy. escheric ... | 2008 | 19461940 |
| evaluation of salmonella live vaccines with chromosomal expression cassettes for translocated fusion proteins. | salmonella enterica is a versatile live carrier for the presentation of recombinant vaccine antigens. fusion proteins of a type iii secretion system effector and heterologous vaccine antigens can be translocated by live attenuated salmonella strains and mediate protective immunity against infections. here we investigated the use expression cassettes for translocated fusion protein consisting of effector ssef and antigens of listeria monocytogenes after stable integration into the salmonella chro ... | 2009 | 19464562 |
| effect of fat content on survival of listeria monocytogenes during simulated digestion of inoculated beef frankfurters stored at 7 degrees c. | potential effects of the fat content of frankfurters on the gastrointestinal survival of listeria monocytogenes were investigated. at various stages of storage (7 degrees c, up to 55 days), inoculated frankfurters of low (4.5%) and high (32.5%) fat content were exposed to a dynamic gastrointestinal model (37 degrees c) and l. monocytogenes counts were determined at intervals during exposure in each gastrointestinal compartment (gastric, gc; intestinal, ic). bacterial survival curves in each comp ... | 2009 | 19465244 |
| distribution of serotypes and pulsotypes of listeria monocytogenes from human, food and environmental isolates (italy 2002-2005). | this work was undertaken to study the serotypes and pulsotypes of 674 listeria monocytogenes isolates from human (57), food (558) and environmental (59) sources, collected from different italian geographical areas during 2002-2005, to determine whether certain subtypes were associated with certain foods and more often involved in cases of listeriosis, and to determine possible geographical or temporal associations. eleven different l. monocytogenes serotypes were found in the food, environmental ... | 2009 | 19465249 |
| spr1630 is responsible for the lethality of clpx mutations in streptococcus pneumoniae. | the clp protease atpase subunit and chaperone clpx is dispensable in some bacteria, but it is thought to be essential in others, including streptococci and lactococci. we confirm that clpx is essential in the rx strain of streptococcus pneumoniae but show that the requirement for clpx can be relieved by point mutations, frame shifts, or deletion of the gene spr1630, which is found in many isolates of s. pneumoniae. homologs occur frequently in staphylococcus aureus as well as in a few strains of ... | 2009 | 19465654 |
| predictors of mortality and impact of aminoglycosides on outcome in listeriosis in a retrospective cohort study. | gentamicin is often used to treat listeriosis, particularly in patients with meningitis; nonetheless, some clinicians question this practice because of the drug's associated nephrotoxicity and inability to cross the blood-brain barrier. the aim of this study was to evaluate predictors of mortality and the impact of aminoglycosides on outcome in patients with listeriosis. | 2009 | 19468027 |
| evaluating the effect of environmental factors on pathogen regrowth in compost extract. | pathogenic microorganisms may survive the composting process in low numbers and subsequently regrow to high levels under favorable conditions. the objective of this study was to investigate the regrowth potential of salmonella spp., escherichia coli o157:h7, and listeria monocytogenes in dairy-based composts under different environmental conditions. water extract of commercially available dairy compost was used as a model system. cocktails of five rifampin-resistant strains of each pathogen prev ... | 2009 | 19468701 |
| rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method. | to develop a new, rapid and accurate reverse dot blot (rdb) method for the detection of intestinal pathogens in fecal samples. | 2009 | 19469006 |
| [prolonged fever and monocytosis after hemorrhoidectomy and treatment with methotrexate--listeriosis with cerebral abscess]. | a 58-year-old man was admitted because of septic fever for about one week with onset two weeks after an hemorrhoidectomy. he had been receiving methotrexate (mtx) since boyhood for severe psoriasis. fifteen years before he had undergone a splenectomy after abdominal trauma. the patient was found to have diminished cognitive functions and memory disturbance, but no focal neurological deficits. | 2009 | 19472093 |
| beta-lactones decrease the intracellular virulence of listeria monocytogenes in macrophages. | | 2009 | 19472261 |
| listeriolysin o as cytotoxic component of an immunotoxin. | monoclonal antibodies (mabs) have been developed over the past years as promising anticancer therapeutics. the conjugation of tumor specific mabs with cytotoxic molecules has been shown to improve their efficacy dramatically. these bifunctional immunotoxins, consisting of covalently linked antibodies and protein toxins, possess considerable potential in cancer therapy. many of them are under investigation in clinical trials. as a result of general interest in new toxic components, we describe he ... | 2009 | 19472336 |
| neuropathogenesis of naturally occurring encephalitis caused by listeria monocytogenes in ruminants. | listeriosis is a serious food-borne disease with increasing frequency in humans and ruminants. despite the facts that in both hosts, listeriosis can occur as rhombencephalitis and ruminants are a reservoir of listeria monocytogenes (lm) strains pathogenic for humans, little work has been done on the pathogenesis in ruminants. this study investigates the neuropathogenesis of listeric encephalitis in over 200 natural cases in cattle, sheep and goats by analyzing anatomical distribution, severity, ... | 2010 | 19476464 |
| exposure to bile influences biofilm formation by listeria monocytogenes. | in the present study we demonstrate that the initial attachment of listeria monocytogenes cells to plastic surfaces was significantly increased by growth in the presence of bile. improved biofilm formation was confirmed by crystal violet staining, microscopy and bioluminescence detection of a luciferase-tagged strain. enhanced biofilm formation in response to bile may influence the ability of l. monocytogenes to form biofilms in vivo during infection and may contribute to survival of this import ... | 2009 | 19476630 |
| microbial ecology of gorgonzola rinds and occurrence of different biotypes of listeria monocytogenes. | in this study we investigated the microbiota of gorgonzola rinds and maturing shelf swabs collected in 5 different maturing cellars in the northwest part of italy, in association with the detection and characterization of listeria monocytogenes. culture-dependent and -independent methods were performed in order to profile the main microbial populations present on the rinds and in the maturing shelves and species-specific pcr and pulsed field gel electrophoresis (pfge) were used to identify and t ... | 2009 | 19477544 |
| in vivo transcriptional profiling of listeria monocytogenes and mutagenesis identify new virulence factors involved in infection. | listeria monocytogenes is a human intracellular pathogen able to colonize host tissues after ingestion of contaminated food, causing severe invasive infections. in order to gain a better understanding of the nature of host-pathogen interactions, we studied the l. monocytogenes genome expression during mouse infection. in the spleen of infected mice, approximately 20% of the listeria genome is differentially expressed, essentially through gene activation, as compared to exponential growth in rich ... | 2009 | 19478867 |
| [characterization of listeria monocytogenes isolates obtained from raw cheese samples acquired from different costa rican producer zones]. | in costa rica, almost 25% of the national milk production is used for the elaboration of non pasteurized soft cheese, and the annual intake of this product is around 4-5 kg per capita. this product has been identified as the source of food borne outbreaks due to listeria monocytogenes. given that, the isolation and identification of this bacterium from non pasteurized soft cheese samples coming from two producer zones of costa rica was performed. 110 cheese samples were collected, from which 27 ... | 2009 | 19480346 |
| a dna array based assay for the characterization of microbial community in raw milk. | an oligonucleotide array based on pcr method containing a combination of probes for taxonomic markers and species-specific virulence genes was developed for the simultaneous identification of 14 lactic acid bacteria (lab) and food-borne pathogenic bacteria in raw milk. the hypervariable regions v3 and v6 of 16s, together with a variable region of 23s rrna genes and several genes specific for virulence factors were selected. universal primers and multiplex pcr were used for the rapid differentiat ... | 2009 | 19482050 |
| lactococcus lactis expressing either staphylococcus aureus fibronectin-binding protein a or listeria monocytogenes internalin a can efficiently internalize and deliver dna in human epithelial cells. | lactococci are noninvasive bacteria frequently used as protein delivery vectors and, more recently, as in vitro and in vivo dna delivery vehicles. we previously showed that a functional eukaryotic enhanced green fluorescent protein (egfp) expression plasmid vector was delivered in epithelial cells by lactococcus lactis producing listeria monocytogenes internalin a (l. lactis inla(+)), but this strategy is limited in vivo to transgenic mice and guinea pigs. in this study, we compare the internali ... | 2009 | 19482952 |
| surfactin reduces the adhesion of food-borne pathogenic bacteria to solid surfaces. | to investigate the effect of the biosurfactants surfactin and rhamnolipids on the adhesion of the food pathogens listeria monocytogenes, enterobacter sakazakii and salmonella enteritidis to stainless steel and polypropylene surfaces. | 2009 | 19486287 |
| evaluation of a mathematical model structure describing the effect of (gel) structure on the growth of listeria innocua, lactococcus lactis and salmonella typhimurium. | to evaluate a novel secondary model structure (int j food microbiol 2008; 128: 67) that describes the effect of medium structure on the maximum specific growth rate (mu(max)) of salmonella typhimurium on the growth of s. typhimurium, listeria innocua, lactococcus lactis and listeria monocytogenes. | 2009 | 19486414 |
| lymphocytes serve as a reservoir for listeria monocytogenes growth during infection of mice. | it is widely reported that listeria monocytogenes can infect virtually all cell types, however, the degree to which this facultative intracellular pathogen can infect lymphocytes has not been well characterized. previous studies have shown that a subset of lymphocytes, including activated t cells, are susceptible to apoptosis following exposure to l. monocytogenes, but the ability of the bacteria to replicate in the cytosol of lymphocytes prior to cell death was not examined. in this report, we ... | 2009 | 19490833 |
| the t cell stat signaling network is reprogrammed within hours of bacteremia via secondary signals. | the delicate balance between protective immunity and inflammatory disease is challenged during sepsis, a pathologic state characterized by aspects of both a hyperactive immune response and immunosuppression. the events driven by systemic infection by bacterial pathogens on the t cell signaling network that likely control these responses have not been illustrated in great detail. we characterized how intracellular signaling within the immune compartment is reprogrammed at the single cell level wh ... | 2009 | 19494279 |
| involvement of cd252 (cd134l) and il-2 in the expression of cytotoxic proteins in bacterial- or viral-activated human t cells. | regulation of cytotoxic effector molecule expression in human ctls after viral or bacterial activation is poorly understood. by using human autologous dendritic cells (dcs) to prime t lymphocytes, we found perforin only highly up-regulated in virus- (hsv-1, vaccinia virus) but not in intracellular bacteria- (listeria innocua, listeria monocytogenes, mycobacterium tuberculosis, chlamydophila pneumoniae) activated ctls. in contrast, larger quantities of ifn-gamma and tnf-alpha were produced in lis ... | 2009 | 19494280 |
| correlations between carbon metabolism and virulence in bacteria. | bacteria have developed several mechanisms which allow the preferred utilization of the most efficiently metabolizable carbohydrates when these organisms are exposed to a mixture of carbon sources. interestingly, the same or similar mechanisms are used by some pathogens to control various steps of their infection process. the efficient metabolism of a carbon source might serve as signal for proper fitness. alternatively, the presence of a specific carbon source might indicate to bacterial cells ... | 2009 | 19494580 |
| enhancing cd8 t-cell memory by modulating fatty acid metabolism. | cd8 t cells, which have a crucial role in immunity to infection and cancer, are maintained in constant numbers, but on antigen stimulation undergo a developmental program characterized by distinct phases encompassing the expansion and then contraction of antigen-specific effector (t(e)) populations, followed by the persistence of long-lived memory (t(m)) cells. although this predictable pattern of cd8 t-cell responses is well established, the underlying cellular mechanisms regulating the transit ... | 2009 | 19494812 |
| perturbation of vacuolar maturation promotes listeriolysin o-independent vacuolar escape during listeria monocytogenes infection of human cells. | listeria monocytogenes is a bacterial pathogen that replicates within the cytosol of infected host cells. the ability to rapidly escape the phagocytic vacuole is essential for efficient intracellular replication. in the murine model of infection, the pore-forming cytolysin listeriolysin o (llo) is absolutely required for vacuolar dissolution, as llo-deficient (deltallo) mutants remain trapped within vacuoles. in contrast, in many human cell types deltallo l. monocytogenes are capable of vacuolar ... | 2009 | 19500109 |
| antibacterial activity of recombinant human lactoferrin from rice: effect of heat treatment. | the antibacterial activity of recombinant human lactoferrin from rice (rhlf) compared with that of human milk lactoferrin (hlf) was evaluated against escherichia coli o157:h7, salmonella enteritidis and listeria monocytogenes. the hydrolysates of rhlf and hlf were found to be more active than native proteins against e. coli o157:h7, and their activity was independent of their iron saturation. the effect of different heat treatments on the antibacterial activity of apo-rhlf was studied and compar ... | 2009 | 19502737 |
| species-specific detection of listeria monocytogenes using polymerase chain reaction assays targeting the prfa virulence gene cluster. | sequence comparison of individual genes in the prfa virulence gene cluster (pvgc), a central virulence gene cluster, from different listeria species indicated that priming sites within the genes appeared to be specific for listeria monocytogenes exclusively. therefore, the pvgc was targeted for polymerase chain reaction (pcr) assays to detect and specifically identify l. monocytogenes. each gene of the pvgc was specifically amplified in l. monocytogenes but not in other listeria species. | 2009 | 19502760 |
| particle size determines activation of the innate immune system in the lung. | our knowledge about particle size in relation to activation of the innate immune system is limited. therefore, the acute effect of particle exposure on the innate immune system was studied in a lung model using the intracellular bacterium listeria monocytogenes. female balb/ca mice were instilled intratracheally with polystyrene particles (psp) of different diameters (0.064, 0.202, 1.053 and 4.646 mum) simultaneously with or 1 day prior to inoculation of 10(5) bacteria. mice were sacrificed 1 da ... | 2009 | 19508373 |
| immunotoxicological profile of chloroform in female b6c3f1 mice when administered in drinking water. | chloroform can be formed as a disinfection by-product during water chlorination, one of the primary modalities for purifying municipal water supplies for human consumption. the aim of this study was to characterize the immunotoxic effects of chloroform in female b6c3f1 mice when exposure occurred via the drinking water. consistent with human exposure, female b6c3f1 mice were exposed to chloroform-containing drinking water at 2.5, 10, 25, 100, and 250 ppm for 28 days. the examined endpoints inclu ... | 2009 | 19514942 |
| prevalence and challenge tests of listeria monocytogenes in belgian produced and retailed mayonnaise-based deli-salads, cooked meat products and smoked fish between 2005 and 2007. | processed ready-to-eat (rte) foods with a prolonged shelf-life under refrigeration are at risk products for listeriosis. this manuscript provides an overview of prevalence data (n=1974) and challenge tests (n=299) related to listeria monocytogenes for three categories of rte food i) mayonnaise-based deli-salads (1187 presence/absence tests and 182 challenge tests), ii) cooked meat products (639 presence/absence tests and 92 challenge tests), and iii) smoked fish (90 presence/absence tests and 25 ... | 2009 | 19515447 |
| quantitative risk assessment for listeria monocytogenes in selected categories of deli meats: impact of lactate and diacetate on listeriosis cases and deaths. | foodborne disease associated with consumption of ready-to-eat foods contaminated with listeria monocytogenes represents a considerable pubic health concern. in a risk assessment published in 2003, the u.s. food and drug administration and the u.s. food safety and inspection service estimated that about 90% of human listeriosis cases in the united states are caused by consumption of contaminated deli meats. in this risk assessment, all deli meats were grouped into one of 23 categories of ready-to ... | 2009 | 19517724 |
| efficacy of sanitizing agents against listeria monocytogenes biofilms on high-density polyethylene cutting board surfaces. | this study compared the effectiveness of 10 commercially available sanitizers against listeria monocytogenes biofilms on high-density polyethylene cutting boards. smooth and rough surface high-density polyethylene coupons (2 by 5 cm) were inoculated (approximately 6 log cfu/cm2) with a five-strain composite of l. monocytogenes in ham homogenate and incubated at 24 degrees c and > or = 90% relative humidity for up to 21 days. the coupons were subjected to repeated 24-h cycles simulating use and c ... | 2009 | 19517725 |
| diversity assessment of heat resistance of listeria monocytogenes strains in a continuous-flow heating system. | listeria monocytogenes is a foodborne pathogen that has the ability to survive relatively high temperatures compared with other nonsporulating foodborne pathogens. this study was performed to determine whether l. monocytogenes strains with relatively high heat resistances are adequately inactivated in a high-temperature, short-time pasteurization process (72 degrees c for 15 s). to obtain heat-resistant strains, 48 strains were exposed to 55 degrees c for up to 3 h. the energy of activation cons ... | 2009 | 19517726 |
| photodynamic treatment: a novel method for sanitation of food handling and food processing surfaces. | the photodynamic bactericidal effect of the photoactive dyes acriflavine neutral, rose bengal, phloxine b, and malachite green (oxalate salt) at concentrations of 5 to 5,000 microg/ml against two gram-negative strains (escherichia coli ljh 128 and salmonella typhimurium c1058), two gram-positive strains (bacillus sp. c578 and listeria monocytogenes ljh 375), and yeast (saccharomyces cerevisiae c1172) was investigated. incubation of the investigated bacteria with acriflavine neutral under illumin ... | 2009 | 19517729 |
| efficacy of sodium hypochlorite and peroxyacetic acid to reduce murine norovirus 1, b40-8, listeria monocytogenes, and escherichia coli o157:h7 on shredded iceberg lettuce and in residual wash water. | the efficiency of sodium hypochlorite (naocl) and peroxyacetic acid (paa) to reduce murine norovirus 1 (mnv-1), a surrogate for human norovirus, and bacteroides fragilis hsp40-infecting phage b40-8 on shredded iceberg lettuce was investigated. the levels of removal of viruses mnv-1 and b40-8 were compared with the reductions observed for bacterial pathogens listeria monocytogenes and escherichia coli o157:h7. two inoculation levels, one with a high organic load and the other containing a 10-fold ... | 2009 | 19517733 |
| inhibitory effect of commercial green tea and rosemary leaf powders on the growth of foodborne pathogens in laboratory media and oriental-style rice cakes. | the antimicrobial effects of green tea and rosemary added to foods as antagonists to foodborne pathogens were determined in laboratory media and oriental-style rice cakes. the growth of each pathogen (bacillus cereus, salmonella typhimurium, enterobacter sakazakii, escherichia coli o157:h7, staphylococcus aureus, and listeria monocytogenes) in tryptic soy broth or rice cake with or without addition of green tea or rosemary leaf powders before autoclaving or cooking, respectively, was investigate ... | 2009 | 19517743 |
| [genoserotyping of listeria monocytogenes in multiplex pcr]. | listeria monocytogenes infection affects people throughout the all world, most often causing gastrointestinal disturbances, less inflammation of the central nervous system (meningitis, meningoencephalitis, absceses), sepsis, endocarditis and dispersed focal inflammation. listeria monocytogenes infection in pregnant woman can lead also to premature birth or abortion. listeriosis is a serious problem because of the high mortality in case of generalized infection, which can reach up to 20%. listeri ... | 2009 | 19517817 |
| the soluble nickel component of residual oil fly ash alters pulmonary host defense in rats. | the soluble metal fraction of residual oil fly ash (rofa) has been shown to increase the susceptibility to infection in animal models. the goal of this study was to determine which of the primary soluble metals or metal combinations in rofa were responsible for the increased infectivity. the soluble fraction of rofa contained ni, fe, al, and zn. on day 0, sprague-dawley rats were intratracheally (it) instilled with nicl2 (55.7 microg/rat), feso4 (32.7 microg/rat), al3(so4)2 (46.6 microg/rat), or ... | 2009 | 19519163 |
| enhanced bactericidal activity of enterocin as-48 in combination with essential oils, natural bioactive compounds and chemical preservatives against listeria monocytogenes in ready-to-eat salad. | enterocin as-48 (30-60 microg/g) significantly reduced viable counts of listeria monocytogenes in russian-type salad during one week storage at 10 degrees c. antilisterial activity of as-48 (30 microg/g) in salad was strongly enhanced by essential oils (thyme verbena, thyme red, spanish oregano, ajowan, tea tree, clove, and sage oils tested at 1%, as well as with 2% rosemary oil). antilisterial activity also increased in combination with bioactive components from essential oils and plant extract ... | 2009 | 19520136 |
| surveillance for foodborne disease outbreaks - united states, 2006. | foodborne illnesses are a major health burden in the united states. most of these illnesses are preventable, and analysis of outbreaks helps identify control measures. although most cases are sporadic, investigation of the portion that occur as part of recognized outbreaks can provide insights into the pathogens, food vehicles, and food-handling practices associated with foodborne infections. cdc collects data on foodborne disease outbreaks (fbdos) from all states and territories through the foo ... | 2009 | 19521332 |
| imaging listeria monocytogenes infection in vivo. | listeria monocytogenes infection in mice is a highly prolific model of bacterial infection. several in vivo imaging approaches have been used to study host cell dynamics in response to infection, including bioluminescence imaging, confocal microscopy and two-photon microscopy, the application of in vivo imaging to study transgenic mouse models is providing unprecedented opportunities to test specific molecular mechanistic theories about how the host immune response unfolds. in complementary stud ... | 2009 | 19521687 |
| [meningitis due to listeria monocytogenes during adalimumab therapy]. | | 2009 | 19525035 |
| insight into the core and variant exoproteomes of listeria monocytogenes species by comparative subproteomic analysis. | while listeria monocytogenes is responsible for listeriosis, it is also a saprophytic species with exceptional survival aptitudes. secreted proteins are one of the main tools used by bacteria to interact with their environment. in order to take into account the biodiversity of l. monocytogenes species, exoproteomic analysis was carried out on 12 representative strains. following 2-de and maldi-tof ms, a total of 151 spots were identified and corresponded to 60 non-orthologous proteins. to catego ... | 2009 | 19526548 |
| a new platform for real-time pcr detection of salmonella spp., listeria monocytogenes and escherichia coli o157 in milk. | intoxications and infections caused by food-borne pathogens represent an increasing public health problem, and diagnostic tests in multiplex format are needed for the rapid identification of food contaminations caused by more than one microbial species. we have developed a multiple pcr-based platform for the simultaneous detection of the widespread milk-associated pathogens salmonella spp., listeria monocytogenes and escherichia coli o157. the assay combines an enrichment step in a medium proper ... | 2009 | 19527837 |
| effects of curing sodium nitrite additive and natural meat fat on growth control of listeria monocytogenes by the bacteriocin-producing lactobacillus curvatus strain cwbi-b28. | in realistic model meat systems, the separate and combined effects of fat content and sodium nitrite on the antilisterial activity of the bacteriocin of lactobacillus curvatus cwbi-b28 were studied. in laboratory fermentations where listeria monocytogenes was co-cultured at 4 degrees c with bacteriocin-producing cwbi-b28 in lean pork meat (fat content: 13%) without added nitrite, a strong antilisterial effect was observed after one week. the effect was maintained for an additional week, after wh ... | 2009 | 19527838 |
| selection and evaluation of seafood-borne psychrotrophic lactic acid bacteria as inhibitors of pathogenic and spoilage bacteria. | in this study, inhibitory psychrotrophic lactic acid bacteria were isolated and investigated for future use in biopreservation of seafood products. screening of 5575 colonies isolated from various seafood products resulted in the selection of 132 colonies presenting inhibitory properties. among them, 52 isolates had characteristics of lab and showed growth at 15 degrees c but not at 30 degrees c. the inhibition spectrum of these 52 isolates against 14 target strains (gram-positive and -negative) ... | 2009 | 19527840 |
| modelling the growth of listeria monocytogenes in fresh green coconut (cocos nucifera l.) water. | the behaviour of listeria monocytogenes in the fresh coconut water stored at 4 degrees c, 10 degrees c and 35 degrees c was studied. the coconut water was aseptically extracted from green coconuts (cocos nucifera l.) and samples were inoculated in triplicate with a mixture of 5 strains of l. monocytogenes with a mean population of approximately 3 log(10) cfu/ml. the kinetic parameters of the bacteria were estimated from the baranyi model, and compared with predictions of the pathogen modelling p ... | 2009 | 19527842 |
| impact of preexisting vector-specific immunity on vaccine potency: characterization of listeria monocytogenes-specific humoral and cellular immunity in humans and modeling studies using recombinant vaccines in mice. | recombinant live-attenuated listeria monocytogenes is currently being developed as a vaccine platform for treatment or prevention of malignant and infectious diseases. the effectiveness of complex biologic vaccines, such as recombinant viral and bacterial vectors, can be limited by either preexisting or vaccine-induced vector-specific immunity. we characterized the level of l. monocytogenes-specific cellular and humoral immunity present in more than 70 healthy adult subjects as a first step to u ... | 2009 | 19528221 |
| listeria meningoencephalitis in an immunocompetent person. | listeria monocytogenes is a small, aerobic or facultative anaerobic, non-sporulating gram positive bacillus that can be isolated from soil, vegetation or animal reservoirs. there are six species of listeria, and only l. monocytogenes is pathogenic for humans. human disease occurs mainly in immunocompromised people, neonates and in pregnancy, while the cases in immunocompetent people are rare. cns manifestations of the disease can be in form of meningitis, encephalitis, and also cerebritis and ab ... | 2009 | 19537672 |
| [listeria monocytogenes prosthetic joint infection: case report and review of the literature]. | listeria monocytogenes is an unusual pathogenic agent in the general population, but is an important cause of bacteriemia and meningoencephalitis among newborns, pregnant women, the elderly population, and immunosuppressed patients. in rare cases, it has been described in joint prosthesis infections. | 2009 | 19539406 |
| [listeria monocytogenes crossing of the placental barrier]. | | 2009 | 19541226 |
| in vivo study on the effectiveness of pediocin pa-1 and pediococcus acidilactici ul5 at inhibiting listeria monocytogenes. | the anti-listerial effect of pediocin pa-1 and its producing strain, pediococcus acidilactici ul5, was investigated in vivo using an icr mouse model. the effect of intra-gastric administration of a single dose of p. acidilactici ul5 (4 x 10(10) cfu/animal) on the propagation of listeria monocytogenes lsd348 in intestine, liver and spleen was negligible. p. acidilactici ul5 did not appear competitive with the mouse intestinal flora and was not detectable in fecal samples collected two days after ... | 2009 | 19541383 |
| the interaction between listeria monocytogenes and the host gastrointestinal tract. | listeria monocytogenes is a ubiquitous bacterium that causes significant foodborne disease with high mortality rates in immunocompromised adults. in pregnant women foodborne infection can give rise to infection of the fetus resulting in miscarriage. in addition, the bacterium has recently been demonstrated to cause localized gastrointestinal symptoms, predominantly in immunocompetent individuals. the murine model of systemic l. monocytogenes infection has provided numerous insights into the mech ... | 2009 | 19542009 |
| role of growth temperature in freeze-thaw tolerance of listeria spp. | the food-borne pathogen listeria monocytogenes can grow in a wide range of temperatures, and several key virulence determinants of the organism are expressed at 37 degrees c but are strongly repressed below 30 degrees c. however, the impact of growth temperature on the ability of the bacteria to tolerate environmental stresses remains poorly understood. in other microorganisms, cold acclimation resulted in enhanced tolerance against freezing and thawing (cryotolerance). in this study, we investi ... | 2009 | 19542335 |
| il-23 promotes the production of il-17 by antigen-specific cd8 t cells in the absence of il-12 and type-i interferons. | in contrast to cd4 t cells, cd8 t cells inherently differentiate into ifn-gamma-producing effectors. accordingly, while generation of ifn-gamma-producing th1 cd4 t cells was profoundly impaired in mice deficient for both type-i ifn and il-12 signaling in response to infection with listeria monocytogenes, generation of ag-specific, ifn-gamma-producing cd8 t cells was unimpaired. however, a fraction of these cd8 t cells also produced il-17 in an il-23-dependent manner. furthermore, the addition of ... | 2009 | 19542449 |
| on the lookout for listeriosis. | | 2009 | 19543046 |
| il-15 is critical for the maintenance and innate functions of self-specific cd8(+) t cells. | il-15 is a pleiotropic cytokine involved in host defense as well as autoimmunity. il-15-deficient mice show a decrease of memory phenotype (mp) cd8(+) t cells, which develop naturally in naïve mice and whose origin is unclear. it has been shown that self-specific cd8(+) t cells developed in male h-y antigen-specific tcr transgenic mice share many similarities with naturally occurring mp cd8(+) t cells in normal mice. in this study, we found that h-y antigen-specific cd8(+) t cells in male but no ... | 2009 | 19544306 |
| real-time observation of listeria monocytogenes-phagocyte interactions in living zebrafish larvae. | the zebrafish, danio rerio, has become a popular vertebrate model for the study of infections, mainly because of its excellent optical accessibility at the embryonic and larval stages, when the innate immune system is already effective. we have thus tested the susceptibility of zebrafish larvae to the human pathogen listeria monocytogenes, a gram-positive, facultative, intracellular bacterium that is known to survive and multiply in professional phagocytes and that causes fatal meningitis and ab ... | 2009 | 19546195 |