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reservoirs of listeria species in three environmental ecosystems.soil and water are suggested to represent pivotal niches for the transmission of listeria monocytogenes to plant material, animals, and the food chain. in the present study, 467 soil and 68 water samples were collected in 12 distinct geological and ecological sites in austria from 2007 to 2009. listeria was present in 30% and 26% of the investigated soil and water samples, respectively. generally, the most dominant species in soil and water samples were listeria seeligeri, l. innocua, and l. iva ...201425002422
response to comment on "tim-3 directly enhances cd8 t cell responses to acute listeria monocytogenes infection". 201424994908
comment on "tim-3 directly enhances cd8 t cell responses to acute listeria monocytogenes infection". 201424994907
perinatal immunization with vaccine-grade listeria monocytogenes provides protection against murine th2 airway inflammation.asthma is a chronic respiratory disorder that leads to inflammation and narrowing of the airways. its global prevalence has attained epidemic levels and treatment options that reach beyond temporary relief of symptoms are urgently needed. since the processes leading to clinically symptomatic asthma start early in life, we set out to systematically evaluate a neonatal immunotherapeutic based on listeria monocytogenes (lm) for the control of allergic sensitization.201424991458
schistosoma mansoni soluble egg antigens enhance listeria monocytogenes vector hiv-1 vaccine induction of cytotoxic t cells.vaccines are an important public health measure for prevention and treatment of diseases. in addition to the vaccine immunogen, many vaccines incorporate adjuvants to stimulate the recipient's immune system and enhance vaccine-specific responses. while vaccine development has advanced from attenuated organism to recombinant protein or use of plasmid dna, the development of new adjuvants that safely increase immune responses has not kept pace. previous studies have shown that the complex mixture ...201424990901
inactivation kinetics of escherichia coli o157:h7, salmonella enterica serovar typhimurium, and listeria monocytogenes in ready-to-eat sliced ham by near-infrared heating at different radiation intensities.the aim of this study was to investigate the inactivation kinetics of salmonella enterica serovar typhimurium, escherichia coli o157:h7, and listeria monocytogenes on ready-to-eat sliced ham by near-infrared (nir) heating as a function of the processing parameter, radiation intensity. precooked ham slices inoculated with the three pathogens were treated at different nir intensities (ca. 100, 150, and 200 μw/cm(2)/nm). an increase in the applied radiation intensity resulted in a gradual increase ...201424988034
metal-chelating active packaging film enhances lysozyme inhibition of listeria monocytogenes.several studies have demonstrated that metal chelators enhance the antimicrobial activity of lysozyme. this study examined the effect of metal-chelating active packaging film on the antimicrobial activity of lysozyme against listeria monocytogenes. polypropylene films were surface modified by photoinitiated graft polymerization of acrylic acid (pp-g-paa) from the food contact surface of the films to impart chelating activity based on electrostatic interactions. pp-g-paa exhibited a carboxylic ac ...201424988022
low occurrence of listeria monocytogenes on bovine hides and carcasses in minas gerais state, brazil: molecular characterization and antimicrobial resistance.listeria monocytogenes occurrence was assessed in three slaughterhouses located in minas gerais state, brazil, by analysis of 209 bovine carcasses. four sponge samples were obtained from each carcass in different steps (a, from hide, before bleeding; b, after hide removal; c, after evisceration; and d, after end washing), resulting in a total of 836 samples. the samples were tested for the presence of l. monocytogenes according to the international organization for standardization 11290-1, and p ...201424988021
the receptor for the complement c3a anaphylatoxin (c3ar) provides host protection against listeria monocytogenes-induced apoptosis.listeria monocytogenes is a gram-positive intracellular bacterium that is acquired through tainted food and may lead to systemic infection and possible death. despite the importance of the innate immune system in fighting l. monocytogenes infection, little is known about the role of complement and its activation products, including the potent c3a anaphylatoxin. in a model of systemic l. monocytogenes infection, we show that mice lacking the receptor for c3a (c3ar(-/-)) are significantly more sen ...201424981453
microbiological challenge testing for listeria monocytogenes in ready-to-eat food: a practical approach.food business operators (fbos) are the primary responsible for the safety of food they place on the market. the definition and validation of the product's shelf-life is an essential part for ensuring microbiological safety of food and health of consumers. in the frame of the regulation (ec) no 2073/2005 on microbiological criteria for foodstuffs, fbos shall conduct shelf-life studies in order to assure that their food does not exceed the food safety criteria throughout the defined shelf-life. in ...201427800369
regulation of autophagy by e3 ubiquitin ligase rnf216 through becn1 ubiquitination.autophagy is an evolutionarily conserved biological process involved in an array of physiological and pathological events. without proper control, autophagy contributes to various disorders, including cancer and autoimmune and inflammatory diseases. it is therefore of vital importance that autophagy is under careful balance. thus, additional regulators undoubtedly deepen our understanding of the working network, and provide potential therapeutic targets for disorders. in this study, we found tha ...201425484083
complete genome sequence of listeria monocytogenes lm60, a strain with an enhanced cold adaptation capacity.the complete genome sequence of listeria monocytogenes lm60, a fast cold-adapting serotype 1/2a human isolate, is presented.201425477407
metal ion homeostasis in listeria monocytogenes and importance in host-pathogen interactions.listeria monocytogenes is responsible for one of the most life-threatening food-borne infections and the leading cause of food-poisoning associated deaths in the uk. infection may be of the unborn/newly born infant where disease may manifest as listeric abortion, stillbirth or late-onset neonatal listeriosis, while in adults, infection usually affects the central nervous system causing meningitis. crucial to the survival of l. monocytogenes, both inside and outside the host, is its ability to ac ...201425476765
influence of temperature, glucose, and iron on sinigrin degradation by salmonella and listeria monocytogenes.factors, including ph, temperature, glucose concentration, and iron compounds, affect the activity of plant myrosinase and, consequently, endogenous glucosinolate degradation. these factors also may affect glucosinolate degradation by bacterial myrosinase. therefore, this study examined the effect of temperature (4 to 21°c), glucose (0.05 to 1.0%), and iron (10 mm ferrous or ferric) on sinigrin degradation by salmonella or listeria monocytogenes cocktails in mueller-hinton broth and the effect o ...201425474062
controlling attachment and growth of listeria monocytogenes in polyvinyl chloride model floor drains using a peroxide chemical, chitosan-arginine, or heat.listeria monocytogenes can colonize a poultry processing plant as a resident in floor drains. limiting growth and attachment to drain surfaces may help lessen the potential for cross-contamination of product. the objective of this study was to compare a hydrogen peroxide-peroxyacetic acid-based chemical to chitosan-arginine or heat to prevent attachment of or destroy existing l. monocytogenes on the inner surface of model floor drains. l. monocytogenes was introduced to result in about 10(9) pla ...201425474061
analysis of listeria monocytogenes strain distribution in a pork slaughter and cutting plant in the province of quebec.following the 2008 canadian listeriosis outbreak associated with ready-to-eat (rte) meat products, regulations on the presence of listeria monocytogenes in rte food production facilities were modified by health canada, confirming the need to control this pathogen, not only in the final product but also in the plant environment. information on the occurrence of this microorganism during the early steps of production, such as the slaughtering process and in the cutting area, is scarce in canada. i ...201425474060
listeria monocytogenes serotype prevalence and biodiversity in diverse food products.the aim of this study was to assess serotype prevalence and biodiversity of listeria monocytogenes strains isolated from diverse food products, i.e., minced pork, fruits, and vegetables. three hundred twenty-six samples previously purchased from supermarkets and street markets within the athens area were studied for l. monocytogenes prevalence. a total of 121 strains were isolated from the 36 samples that were positive for l. monocytogenes. serotyping was performed with multiplex pcr, and biodiv ...201425474059
inactivation of listeria monocytogenes by disinfectants and bacteriophages in suspension and stainless steel carrier tests.to simulate food contact surfaces with pits or cracks, stainless steel plates with grooves (depths between 0.2 and 5 mm) were constructed. these plates were artificially contaminated with listeria monocytogenes in clean conditions, with organic soiling, or after 14 days of biofilm formation after which inactivation of the pathogen by suma tab d4 (sodium dichloroisocyanurate, 240 and 300 mg/liter), suma bac d10 (quaternary ammonium compound, 740 mg/liter), and bacteriophage suspension (listex p10 ...201425474045
identification of listeria monocytogenes determinants required for biofilm formation.listeria monocytogenes is a gram-positive, food-borne pathogen of humans and animals. l. monocytogenes is considered to be a potential public health risk by the u.s. food and drug administration (fda), as this bacterium can easily contaminate ready-to-eat (rte) foods and cause an invasive, life-threatening disease (listeriosis). bacteria can adhere and grow on multiple surfaces and persist within biofilms in food processing plants, providing resistance to sanitizers and other antimicrobial agent ...201425517120
genetic distance in the whole-genome perspective on listeria monocytogenes strains f2-382 and nihs-28 that show similar subtyping results.genome subtyping approaches could provide useful epidemiological information regarding food pathogens. however, the full genomic diversity of strains that show similar subtyping results has not yet been completely explored. most subtyping methods are based on the differences of only a portion of the genome. we investigated two draft genome sequences of listeria monocytogenes strain f2-382 and nihs-28, which have been identified as closely related strains by subtyping (identical multi-virulence-l ...201425492229
suspension of thymic emigration promotes the maintenance of antigen-specific memory t cells and the recall responses.thymic involution is evolutionarily conserved and occurs early in life. however, the physiological significance remains elusive of this seemingly detrimental process. the present study investigated the potential impact of altered thymic output on t cell memory using ovalbumin (ova) expressed by listeria monocytogenes as a model antigen. suspension of thymic emigration by thymectomy was shown to lead to a marked increase in the frequency and total number of ova-specific memory t cells. in contras ...201425450389
comparative analysis of crispr loci in different listeria monocytogenes lineages.listeria monocytogenes, an important food-borne pathogen, causes high mortality rate of listeriosis. pan-genomic comparisons revealed the species genome of l. monocytogenes is highly stable but not completely clonal. the population structure of this species displays at least four evolutionary lineages (i-iv). isolates of different lineages displayed distinct genetic, phenotypic and ecologic characteristics, which appear to affect their ability to be transmitted through foods and to cause human d ...201425445602
[sausage-related listeria monocytogenes infection].infection with listeria monocytogenes is rare and mainly seen in immunosuppressed patients. infection with l. monocytogenes has a mortality rate of 30%. we present a case report of l. monocytogenes bacteraemia and endocarditis in a 70-year-old man with several co-morbidities and following four major surgical procedures. this illustrates the findings and characteristics in one of the 16 patients who died in 2013 and 2014 this summer due to sausage-related l. monocytogenes infection.201425430580
two outbreaks of listeria monocytogenes infection, northern spain.in the province of gipuzkoa, spain (≈700,000 inhabitants), 7-12 episodes of human listeriosis were recorded annually during 2009-2012. however, during january 2013-february 2014, 27 episodes were detected, including 11 pregnancy-associated cases. fifteen cases in 2 epidemiologically unrelated outbreaks were caused by a rare type of listeria monocytogenes, sequence type 87 serotype 1/2b.201425418800
splenectomy alters distribution and turnover but not numbers or protective capacity of de novo generated memory cd8 t-cells.the spleen is a highly compartmentalized lymphoid organ that allows for efficient antigen presentation and activation of immune responses. additionally, the spleen itself functions to remove senescent red blood cells, filter bacteria, and sequester platelets. splenectomy, commonly performed after blunt force trauma or splenomegaly, has been shown to increase risk of certain bacterial and parasitic infections years after removal of the spleen. although previous studies report defects in memory b- ...201425414706
committee opinion no. 614: management of pregnant women with presumptive exposure to listeria monocytogenes.listeriosis is predominantly a foodborne illness, with sporadic and outbreak-related cases tied to consumption of food contaminated with listeria (listeria monocytogenes). the incidence of listeriosis associated with pregnancy is approximately 13 times higher than in the general population. maternal infection may present as a nonspecific, flu-like illness with fever, myalgia, backache, and headache, often preceded by diarrhea or other gastrointestinal symptoms. however, fetal and neonatal infect ...201425411758
prevalence and populations of listeria monocytogenes in meat products retailed in sao paulo, brazil.this study evaluated the prevalence of the populations and serotypes of listeria monocytogenes in 552 refrigerated samples of ground beef, chicken leg, hot dog, and pork sausage collected in supermarkets in the city of sao paulo, sp, brazil, between may 2008 and july 2009. the supermarkets were selected after stratification by geographical region and by random draw. tests for presence and enumeration of l. monocytogenes were based on iso 11290-1:1996/amd.1:2004 and iso 11290-2:1998 methods, resp ...201425407460
analysis of carbon substrates used by listeria monocytogenes during growth in j774a.1 macrophages suggests a bipartite intracellular metabolism.intracellular bacterial pathogens (ibps) are dependent on various nutrients provided by the host cells. different strategies may therefore be necessary to adapt the intracellular metabolism of ibps to the host cells. the specific carbon sources, the catabolic pathways participating in their degradation, and the biosynthetic performances of ibps are still poorly understood. in this report, we have exploited the technique of (13)c-isotopologue profiling to further study the carbon metabolism of li ...201425405102
multivariate analysis reveals differences in biofilm formation capacity among listeria monocytogenes lineages.biofilm formation capacity evaluated under identical conditions differs among listeria monocytogenes lineages. the approach of using one set of factors or one variable at a time fails to explain why some lineages are more prevalent than others in certain environments. this study proposes the use of multivariate analysis to compare biofilm formation by various strains and describes the ecological niches of l. monocytogenes lineages. nutrient availability, temperature, ph and water activity (aw) a ...201425397897
the antimicrobial activity of liquidambar orientalis mill. against food pathogens and antioxidant capacity of leaf extracts.medicinal plants are an important source of substances which are claimed to induce antimicrobial, antimutagenic and antioxidant effects. many plants have been used due to their antimicrobial treatments. antimicrobial and antioxidant activities of l. orientalis have not been reported to the present day. the aim of this work was to investigate of the antimicrobial and antioxidant potentials of different extracts from l. orientalis.201425395700
quantitative proteome analyses identify prfa-responsive proteins and phosphoproteins in listeria monocytogenes.protein phosphorylation is a major mechanism of signal transduction in bacteria. here, we analyzed the proteome and phosphoproteome of a wild-type strain of the food-borne pathogen listeria monocytogenes that was grown in either chemically defined medium or rich medium containing glucose. we then compared these results with those obtained from an isogenic prfa* mutant that produced a constitutively active form of prfa, the main transcriptional activator of virulence genes. in the prfa* mutant gr ...201425383790
intestinal expression of fas and fas ligand is upregulated by bacterial signaling through tlr4 and tlr5, with activation of fas modulating intestinal tlr-mediated inflammation.tlrs play an important role in mediating intestinal inflammation and homeostasis. fas is best studied in terms of its function in apoptosis, but recent studies demonstrate that fas signaling may mediate additional functions such as inflammation. the role of fas, and the fas ligand (fasl), in the intestine is poorly understood. the aim of this study was to evaluate potential cross-talk between tlrs and fas/fasl system in intestinal epithelial cells (iecs). iecs were stimulated with tlr ligands, a ...201425378591
in situ proteolysis, crystallization and preliminary x-ray diffraction analysis of a vhh that binds listeria internalin b.the variable region of camelid heavy-chain antibodies produces the smallest known antibody fragment with antigen-binding capability (a vhh). the vhh r303 binds internalin b (inlb), a virulence factor expressed by the pathogen listeria monocytogenes. inlb is critical for initiation of listeria infection, as it binds a receptor (c-met) on epithelial cells, triggering the entry of bacteria into host cells. inlb is surface-exposed and is required for virulence, hence a vhh targeting inlb has potenti ...201425372824
geographical and meteorological factors associated with isolation of listeria species in new york state produce production and natural environments.listeria species have been isolated from diverse environments, often at considerable prevalence, and are known to persist in food processing facilities. the presence of listeria spp. has been suggested to be a marker for listeria monocytogenes contamination. therefore, a study was conducted to (i) determine the prevalence and diversity of listeria spp. in produce production and natural environments and (ii) identify geographical and/or meteorological factors that affect the isolation of listeria ...201425364926
inactivation of pathogens during aerobic composting of fresh and aged dairy manure and different carbon amendments.two separate studies were conducted to address the condition and the type of feedstocks used during composting of dairy manure. in each study, physical (temperature), chemical (ammonia, volatile acids, and ph), and biological (salmonella, listeria monocytogenes, and escherichia coli o157:h7) parameters were monitored during composting in bioreactors to assess the degree to which they were affected by the experimental variables and, ultimately, the ability of the chemical and physical parameters ...201425364925
genetic and phenotypic characterization of listeria monocytogenes from human clinical cases that occurred in portugal between 2008 and 2012.listeria monocytogenes infection (listeriosis) is an uncommon but severe foodborne illness that affects mainly individuals with recognized underlying conditions: the elderly, immunocompromised individuals, and pregnant women and their fetuses. the aim of this study was to obtain epidemiological data on cases of listeriosis occurring in portugal from 2008 through 2012, collected in hospitals on a voluntary basis. l. monocytogenes isolates were characterized by genoserotyping by multiplex polymera ...201425361468
the listeria small rna rli27 regulates a cell wall protein inside eukaryotic cells by targeting a long 5'-utr variant.listeria monocytogenes is a bacterial pathogen whose genome encodes many cell wall proteins that bind covalently to peptidoglycan. some members of this protein family have a key role in virulence, and recent studies show that some of these, such as lmo0514, are upregulated in bacteria that colonize eukaryotic cells. the regulatory mechanisms that lead to these changes in cell wall proteins remain poorly characterized. here we studied the regulation responsible for increased lmo0514 protein level ...201425356775
listeria infection in chinese pregnant women and neonates from shandong.this study aims to investigate the characters of pregnant women and neonates with listeria monocytogenes infections (l. monocytogenes) in shandong of china.201425356132
bacterial and cellular rnas at work during listeria infection.listeria monocytogenes is an intracellular pathogen that can enter and invade host cells. in the course of its infection, rna-mediated regulatory mechanisms provide a fast and versatile response for both the bacterium and the host. they regulate a variety of processes, such as environment sensing and virulence in pathogenic bacteria, as well as development, cellular differentiation, metabolism and immune responses in eukaryotic cells. the aim of this article is to summarize first the rna-mediate ...201425340833
foodborne illness, australia, circa 2000 and circa 2010.foodborne disease is a major public health problem worldwide. to examine changes in foodborne illness in australia, we estimated the incidence, hospitalizations, and deaths attributed to contaminated food circa 2010 and recalculated estimates from circa 2000. approximately 25% of gastroenteritis cases were caused by contaminated food; to account for uncertainty we used simulation techniques to estimate 90% credible intervals. we estimate that circa 2010, 4.1 million foodborne gastroenteritis cas ...201425340705
of microspheres and microbes: a double-hit strategy for cancer immunotherapy.efficient immunotherapy relies on the rapid generation of elevated amounts of cancer-specific t lymphocytes. we have recently demonstrated that both rapid and potent tumor-targeting immune responses can be induced with a heterologous prime-boost regimen consisting of poly-lactic co-glycolic acid (plga) microsphere-based immunization followed by listeria monocytogenes infection.201425340000
listeria monocytogenes-associated biliary tract infections: a study of 12 consecutive cases and review.at present, little is known regarding listeria monocytogenes-associated biliary tract infection, a rare form of listeriosis.in this article, we will study 12 culture-proven cases reported to the french national reference center for listeria from 1996 to 2013 and review the 8 previously published cases.twenty cases were studied: 17 cholecystitis, 2 cholangitis, and 1 biliary cyst infection. half were men with a median age of 69 years (32-85). comorbidities were present in 80%, including cirrhosis ...201425319439
novel mechanism of hemin capture by hbp2, the hemoglobin-binding hemophore from listeria monocytogenes.iron is an essential nutrient that is required for the growth of the bacterial pathogen listeria monocytogenes. in cell cultures, this microbe secretes hemin/hemoglobin-binding protein 2 (hbp2; lmo2185) protein, which has been proposed to function as a hemophore that scavenges heme from the environment. based on its primary sequence, hbp2 contains three near transporter (neat) domains of unknown function. here we show that each of these domains mediates high affinity binding to ferric heme (hemi ...201425315777
direct incorporation of the nkt-cell activator α-galactosylceramide into a recombinant listeria monocytogenes improves breast cancer vaccine efficacy.immune suppression in the tumour microenvironment remains a major limitation to successful immunotherapy of cancer. in the current study, we analysed whether the natural killer t cell-activating glycolipid α-galactosylceramide could overcome immune suppression and improve vaccination against metastatic breast cancer.201425314062
the listeria monocytogenes transposon tn6188 provides increased tolerance to various quaternary ammonium compounds and ethidium bromide.tolerance of the foodborne pathogen listeria monocytogenes to sublethal concentrations of disinfectants has been frequently reported. particularly, quaternary ammonium compounds (qacs) such as benzalkonium chloride (bc) are often used in disinfectants and also as antiseptics in food industry and hospitals. recently, we described tn6188, a novel transposon in l. monocytogenes harbouring the transporter qach, a molecular mechanism leading to increased tolerance to bc. in this study, we investigate ...201425312720
pregnancy-related listeriosis in france, 1984 to 2011, with a focus on 606 cases from 1999 to 2011.this study describes trends in the incidence of pregnancy-related listeriosis in france between 1984 and 2011, and presents the major characteristics of 606 cases reported between 1999 and 2011 to the french institute for public health surveillance through the mandatory notification system. the incidence of pregnancy-related listeriosis decreased by a factor of 12 from 1984 to 2011. this reduction was a result of progressive implementation of specific listeria monocytogenes control measures in f ...201425306879
impedimetric characterization of adsorption of listeria monocytogenes on the surface of an aluminum-based immunosensor.the impedimetric characteristics of an immunosensor depend on the electrical properties of an immunosensor substrate. the impedimetric characteristics of an immunosensor compared with adsorption of listeria monocytogenes were investigated on an aluminum surface insulated with an electrically resistive aluminum oxide layer. antibody for l. monocytogenes (anti-l. monocytogenes) was immobilized on an aluminum surface that was insulated with a native air-formed aluminum oxide layer. the resistance o ...201425296910
detection of very long antisense transcripts by whole transcriptome rna-seq analysis of listeria monocytogenes by semiconductor sequencing technology.the gram-positive bacterium listeria monocytogenes is the causative agent of listeriosis, a severe food-borne infection characterised by abortion, septicaemia, or meningoencephalitis. l. monocytogenes causes outbreaks of febrile gastroenteritis and accounts for community-acquired bacterial meningitis in humans. listeriosis has one of the highest mortality rates (up to 30%) of all food-borne infections. this human pathogenic bacterium is an important model organism for biomedical research to inve ...201425286309
inhibition of listeria monocytogenes in deli-style turkey breast formulated with cultured celery powder and/or cultured sugar-vinegar blend during storage at 4°c.fermentation-derived nitrite (no2) from vegetable sources is increasingly used as a "clean label" alternative to conventional nano2. previous results suggested that processed meats cured with no2 derived from a "natural" source had lower antimicrobial activity than did meats produced with chemical nano2; however, the differences were likely due to no2 concentration rather than source. the objective of this study was to compare the antilisterial properties of traditional and clean label alternati ...201425285499
decontamination of hard cheeses by pulsed uv light.cheese is a ready-to-eat food that may be contaminated on the surface by undesirable spoilage and pathogenic microorganisms during production, packaging, and postpackaging processes. penicillium roqueforti is commonly found on cheese surfaces at refrigeration temperatures and is one of the most common spoilage fungal species. consumption of cheese contaminated with listeria monocytogenes can result in foodborne listeriosis. therefore, cheese should be decontaminated at postprocessing stages. pul ...201425285489
modeling the effects of temperature, sodium chloride, and green tea and their interactions on the thermal inactivation of listeria monocytogenes in turkey.the interactive effects of heating temperature (55 to 65°c), sodium chloride (nacl; 0 to 2%), and green tea 60% polyphenol extract (gtpe; 0 to 3%) on the heat resistance of a five-strain mixture of listeria monocytogenes in ground turkey were determined. thermal death times were quantified in bags that were submerged in a circulating water bath set at 55, 57, 60, 63, and 65°c. the recovery medium was tryptic soy agar supplemented with 0.6% yeast extract and 1% sodium pyruvate. d-values were anal ...201425285486
detection of listeria monocytogenes in food samples in avezzano, sulmona and castel di sangro (province of l'aquila, abruzzo, italy) between 2000-2009.the retrospective study of the results of the analysed samples is a fundamental tool for the identification of major risk related to food and for planning future monitoring activities. the evaluation of the quality of data collected may also allow for estimating the effectiveness of the controls so to improve their efficacy. in this article, the authors evaluated the results of tests for the detection of listeria monocytogenes performed by the istituto zooprofilattico sperimentale dell'abruzzo e ...201425273959
synergetic effect of combined fumaric acid and slightly acidic electrolysed water on the inactivation of food-borne pathogens and extending the shelf life of fresh beef.to evaluate synergetic effect of slight acidic electrolysed water (saew) and fumaric acid (fa) on inactivation of total viable count (tvc) and staphylococcus aureus, listeria monocytogenes, escherichia coli o157:h7 and salmonella typhimurium in fresh beef and to study shelf life and sensory quality of beef.201425273314
rapid and sensitive detection of listeria monocytogenes by cross-priming amplification of lmo0733 gene.listeria monocytogenes is a food-borne pathogen that causes severe opportunistic infection in humans and animals. this study reports the development of single cross-priming amplification (s-cpa) and double cpa (d-cpa) assays targeting species-specific gene lmo0733 for identifying l. monocytogenes strains. the cpa assays were performed at a constant temperature 64 °c using seven specific primers and evaluated for specificity and sensitivity. the color change of positive amplification was directly ...201425273275
tsc1 promotes the differentiation of memory cd8+ t cells via orchestrating the transcriptional and metabolic programs.memory cd8(+) t cells are an essential component of protective immunity. signaling via mechanistic target of rapamycin (mtor) has been implicated in the regulation of the differentiation of effector and memory t cells. however, little is understood about the mechanisms that control mtor activity, or the effector pathways regulated by mtor. we describe here that tuberous sclerosis 1 (tsc1), a regulator of mtor signaling, plays a crucial role in promoting the differentiation and function of memory ...201425271321
application of high resolution pyrolysis gas chromatography/mass spectrometry (hrpgc/ms) for detecting listeria monocytogenes.the characteristic of listeria monocytogenes' pyrolysis product was found by fingerprint analysis of high resolution pyrolysis gas chromatography and mass spectrometry (hrpgc/ms), which hold a great potential to rapidly detect l. monocytogenes with the application of selected ion monitoring (sim). food products (beef and milk) contaminated by l. monocytogenes and uncontaminated were evaluated. the retention time of the characteristic peak of pyrolysis product was 19.056min, the ion of m/z were 5 ...201425270059
σ(b) affects biofilm formation under the dual stress conditions imposed by adding salt and low temperature in listeria monocytogenes.the food-borne pathogenic bacteria listeria monocytogenes can form biofilms on various surfaces including food-processing equipment. biofilms offer survival benefits to the organisms entrapped against environmental insults. moreover, the σ(b) transcription factor of l. monocytogenes plays an important role in its survival under various stress conditions. in this study, we evaluated whether σ(b) contributes to biofilm formation when l. monocytogenes is grown under various temperatures and media. ...201425269605
chaperone-mediated autophagy regulates t cell responses through targeted degradation of negative regulators of t cell activation.chaperone-mediated autophagy (cma) targets soluble proteins for lysosomal degradation. here we found that cma was activated in t cells in response to engagement of the t cell antigen receptor (tcr), which induced expression of the cma-related lysosomal receptor lamp-2a. in activated t cells, cma targeted the ubiquitin ligase itch and the calcineurin inhibitor rcan1 for degradation to maintain activation-induced responses. consequently, deletion of the gene encoding lamp-2a in t cells caused defi ...201425263126
bacteria detection based on the evolution of enzyme-generated volatile organic compounds: determination of listeria monocytogenes in milk samples.the rapid detection of listeria monocytogenes contamination in food is essential to prevent food-borne illness in humans. the aim of this study was to differentiate non-contaminated milk from milk contaminated with l. monocytogenes using enzyme substrates coupled with the analysis of volatile organic compounds (vocs). the method is based on the activity of β-glucosidase and hippuricase enzymes and the detection of a specific voc i.e. 2-nitrophenol and 3-fluoroaniline, respectively. vocs were ext ...201425263120
adhesion of salmonella enteritidis and listeria monocytogenes on stainless steel welds.pathogenic microorganisms are able to adhere on equipment surfaces, being possible to contaminate food during processing. salmonella spp. and listeria monocytogenes are important pathogens that can be transmitted by food, causing severe foodborne diseases. most surfaces of food processing industry are made of stainless steel joined by welds. however currently, there are few studies evaluating the influence of welds in the microorganism's adhesion. therefore the purpose of the present study was t ...201425261827
whole-genome sequence of listeria monocytogenes type strain 53 xxiii.listeria monocytogenes causes the food-borne illness listeriosis that primarily infects "vulnerable" groups (e.g., elderly adults, pregnant women, very young children, and the immunocompromised). we sequenced the genome of l. monocytogenes xxiii (atcc 15313) and assembled it into a single scaffold (three contigs) and deposited the annotated assembly into genbank as accession no. joox00000000.201425258271
[immunomodulatory role of dietary lipids in an immunosuppressed mouse model and infected with listeria monocytogenes].dietary fatty acids immunomodulatory capacity in immunosuppression conditions may differ according to the type of fatty acid present in the diet.201425335671
salmonella enterica serovar enteritidis and listeria monocytogenes in mango (mangifera indica l.) pulp: growth, survival and cross-contamination.this study examined the ability of salmonella enterica serovar enteritidis and listeria monocytogenes to grow or survive in mango pulp stored at -20°c, 4°c, 10°c and 25°c, as well as to cross-contaminate mangoes by means of a knife contaminated with different levels of these pathogens.201425328926
current status of antisense rna-mediated gene regulation in listeria monocytogenes.listeria monocytogenes is a gram-positive human-pathogen bacterium that served as an experimental model for investigating fundamental processes of adaptive immunity and virulence. recent novel technologies allowed the identification of several hundred non-coding rnas (ncrnas) in the listeria genome and provided insight into an unexpected complex transcriptional machinery. in this review, we discuss ncrnas that are encoded on the opposite strand of the target gene and are therefore termed antisen ...201425325017
drastic therapy for listerial brain abscess involving combined hyperbaric oxygen therapy and antimicrobial agents.listeria monocytogenes (l. monocytogenes) is a rare causative pathogen of brain abscess that is often found in immunocompromised patients. although patients with supratentorial listerial abscesses showed a longer survival with surgical drainage, the standard therapy for patients with subtentorial lesions has not been established.201425324887
phosphotransferase system-dependent extracellular growth of listeria monocytogenes is regulated by alternative sigma factors σl and σh.alternative sigma (σ) factors and phosphotransferase systems (ptss) play pivotal roles in the environmental adaptation and virulence of listeria monocytogenes. the growth of the l. monocytogenes parent strain 10403s and 15 isogenic alternative σ factor mutants was assessed in defined minimal medium (dm) with pts-dependent or non-pts-dependent carbon sources at 25°c or 37°c. overall, our results suggested that the regulatory effect of alternative σ factors on the growth of l. monocytogenes is dep ...201425281379
[effect of ultra high pressure on cell membrane destruction and death of listeria monocytogenes].to study the effect of ultra high pressure (uhp) on the cell membrane of listeria monocytogenes.201425252455
the adaptor asc exacerbates lethal listeria monocytogenes infection by mediating il-18 production in an inflammasome-dependent and -independent manner.listeria monocytogenes induces the formation of inflammasomes and subsequent caspase-1 activation, and the adaptor apoptosis-associated speck-like protein containing a card (asc) is crucial for this response. however, the role of asc in l. monocytogenes infection in vivo is unclear. in this study, we demonstrate that asc has a detrimental effect on host defense against l. monocytogenes infection at a lethal dose (10(6) cfu), but not at a sublethal dose (10(3) cfu). during lethal l. monocytogenes ...201425251560
retardation of listeria monocytogenes growth in mozzarella cheese using antimicrobial sachets containing rosemary oil and thyme oil.an antimicrobial sachet containing microcellular foam starch (mfs) with embedded rosemary oil and thyme oil was developed to reduce bacterial growth in shredded mozzarella cheese. the efficacy of the volatiles of oils at various concentrations in reducing listeria monocytogenes as well as the release of the oils from the mfs have been also determined in this study. the cheese, inoculated with a cocktail of 5 strains of l. monocytogenes (approximately 3 log cfu/g), was packaged in a nylon/evoh/pe ...201425243791
perinatal listeria monocytogenes susceptibility despite preconceptual priming and maintenance of pathogen-specific cd8(+) t cells during pregnancy.listeria monocytogenes (lm) is an intracellular bacterium with unique predisposition for systemic maternal infection during pregnancy and morbid consequences for the developing fetus. given the high mortality associated with prenatal lm infection, strategies for augmenting protective immunity during the exceedingly vulnerable period of pregnancy are urgently needed. herein, protection conferred by attenuated lm administered before pregnancy against subsequent virulent lm prenatal infection was e ...201425242275
the global burden of listeriosis: a systematic review and meta-analysis.listeriosis, caused by listeria monocytogenes, is an important foodborne disease that can be difficult to control and commonly results in severe clinical outcomes. we aimed to provide the first estimates of global numbers of illnesses, deaths, and disability-adjusted life-years (dalys) due to listeriosis, by synthesising information and knowledge through a systematic review.201425241232
lmtdrm database: a comprehensive database on thiol metabolic gene/gene products in listeria monocytogenes egde.there are a number of databases on the listeria species and about their genome. however, these databases do not specifically address a set of network that is important in defence mechanism of the bacteria. listeria monocytogenes egde is a well-established intracellular model organism to study host pathogenicity because of its versatility in the host environment. here, we have focused on thiol disulphide redox metabolic network proteins, specifically in l. monocytogenes egde. the thiol redox meta ...201425228549
sodium chloride-induced filamentation and alternative gene expression of fts, murz, and gnd in listeria monocytogenes 08-5923 on vacuum-packaged ham.the aim of this study was to examine the filament formation and differential gene expression of listeria monocytogenes 08-5923 grown on refrigerated vacuum-packaged ham products with various nacl concentrations. filament formation of l. monocytogenes was observed on ham products with 1.35% and 2.35% nacl, which was monitored using flow cytometry by measuring forward light scatter. quantitative real-time pcr was used to study the differential expression of genes in filamented cells of l. monocyto ...201425227637
potentiometric aptasensing of listeria monocytogenes using protamine as an indicator.exposure to pathogens in recreational or drinking water is a serious public health concern. it is important to rapidly determine and identify trace levels of pathogens in real environmental samples. we report here on a label-free potentiometric aptasensor for rapid, sensitive, and selective detection of listeria monocytogenes (lm), a pathogen widely distributed in the environment. an aptamer binds specifically to internalin a, a surface protein present in lm cells. the target-binding event preve ...201425220163
phylogenetic analysis of the listeria monocytogenes based on sequencing of 16s rrna and hlya genes.the discrimination between listeria monocytogenes and listeria species has been detected. the 16s rrna and hlya were pcr amplified with set of oligonucleotide primers with flank 1,500 and 456 bp fragments, respectively. based on the differences in 16s rrna and hlya genes, a total 80 isolates from different environmental, food and clinical samples confirmed it to be l. monocytogenes. the 16s rrna sequence similarity suggested that the isolates were similar to the previously reported ones from dif ...201425205124
efficacy of acetic acid against listeria monocytogenes attached to poultry skin during refrigerated storage.this work evaluates the effect of acetic acid dipping on the growth of l. monocytogenes on poultry legs stored at 4 °c for eight days. fresh inoculated chicken legs were dipped into either a 1% or 2% acetic acid solution (v/v) or distilled water (control). changes in mesophiles, psychrotrophs, enterobacteriaceae counts and sensorial characteristics (odor, color, texture and overall appearance) were also evaluated. the shelf life of the samples washed with acetic acid was extended by at least two ...201428234335
summary of 11 years of enteric outbreak investigations and criteria to initiate an investigation, province of quebec, 2002 through 2012.this article presents a retrospective analysis of enteric disease outbreak investigations led by or conducted in collaboration with provincial health authorities in the province of quebec from 2002 through 2012. objectives were to characterize enteric disease outbreaks, quantify and describe those for which a source was identified (including the control measures implemented), identify factors that contributed to or impeded identification of the source, and recommend areas for improvement in outb ...201425198848
listeria monocytogenes serotype 1/2b and 4b isolates from human clinical cases and foods show differences in tolerance to refrigeration and salt stress.control of listeria monocytogenes in food processing facilities is a difficult issue because of the ability of this microorganism to form biofilms and adapt to adverse environmental conditions. survival at high concentrations of sodium chloride and growth at refrigeration temperatures are two other important characteristics of l. monocytogenes isolates. the aim of this study was to compare the growth characteristics under stress conditions at different temperatures of l. monocytogenes serotypes ...201425198843
thermal and nonthermal factors affecting survival of salmonella and listeria monocytogenes in animal manure-based compost mixtures.reduction of enteric pathogens in animal manures before field application is essential for mitigating the risk of foodborne illness associated with produce. aerobic composting of manures has been advocated as an effective treatment for reducing pathogen populations, and heat is a major factor contributing to pathogen inactivation. this study was initiated to determine the potential contribution of both thermal and nonthermal (ph, volatile acids, and ammonia) factors to pathogen inactivation duri ...201425198842
prevalence and antimicrobial susceptibility of listeria monocytogenes on chicken carcasses in bandung, indonesia.this study was conducted to determine the prevalence and quantify the number of listeria monocytogenes in fresh chicken carcasses sold in traditional markets and supermarkets in bandung, west java, indonesia, and to determine the antimicrobial resistance patterns of the isolated l. monocytogenes strains. the overall prevalence of l. monocytogenes in chicken carcasses was 15.8% (29/184). when comparing samples from traditional markets and supermarkets, no significant difference in the l. monocyto ...201425198605
comparison of listeria monocytogenes isolates across the island of ireland.building a comprehensive knowledge base of the association of listeria monocytogenes isolates across national food chains, clinical cases, and environments can play a key role in helping control the incidence of listeriosis. today, many food chains cross national borders and are often shared by neighboring countries. this study characterized l. monocytogenes isolated from food samples in northern ireland and investigated whether similarities in the population and associations of l. monocytogenes ...201425198604
low, medium, and high heat tolerant strains of listeria monocytogenes and increased heat stress resistance after exposure to sublethal heat.a group of 37 strains representing all 13 serotypes of listeria monocytogenes with an initial cell density of 10(7) cfu/ml were analyzed for their heat tolerance at 60°c for 10 min. these l. monocytogenes strains were categorized into three heat tolerance groups: low (<2 log cfu/ml survival), medium (2 to 4 log cfu/ml survival), and high (4 to 6 log cfu/ml survival). serotype 1/2a strains had relatively low heat tolerance; seven of the eight tested strains were classified as low heat tolerant. o ...201425198590
growth of listeria monocytogenes, salmonella spp., escherichia coli o157:h7, and staphylococcus aureus on cheese during extended storage at 25°c.potentially hazardous foods require time/temperature control for safety. according to the u.s. food and drug administration food code, most cheeses are potentially hazardous foods based on ph and water activity, and a product assessment is required to evaluate safety of storage >6 h at 21°c. we tested the ability of 67 market cheeses to support growth of listeria monocytogenes (lm), salmonella spp. (salm), escherichia coli o157:h7 (ec), and staphylococcus aureus (sa) over 15 days at 25°c. hard ( ...201425198588
virulence and genotypic characterization of listeria monocytogenes isolated from vegetable and soil samples.listeria monocytogenes, a foodborne pathogen is ubiquitous to different environments including the agroecosystem. the organism poses serious public health problem. therefore, an attempt has been made to gain further insight to their antibiotic susceptibility, serotypes and the virulence genes.201425195727
monitoring occurrence and persistence of listeria monocytogenes in foods and food processing environments in the republic of ireland.although rates of listeriosis are low in comparison to other foodborne pathogenic illness, listeriosis poses a significant risk to human health as the invasive form can have a mortality rate as high as 30%. food processors, especially those who produce ready-to-eat (rte) products, need to be vigilant against listeria monocytogenes, the causative pathogen of listeriosis, and as such, the occurrence of l. monocytogenes in food and in the food processing environment needs to be carefully monitored. ...201425191314
potential of cell-free supernatants from cultures of selected lactic acid bacteria and yeast obtained from local fermented foods as inhibitors of listeria monocytogenes, salmonella spp. and staphylococcus aureus.food-borne infections cause huge economic and human life losses worldwide. the most common contaminants of foods include listeria monocytogenes salmonellae and staphylococcus aureus. l. monocytogenes is most notorious due to its tolerance to common food preservation methods and the risks it poses, including higher fatality rates. safer, more efficacious control methods are thus needed. along with food-borne pathogens, lactic acid bacteria (lab) can also be found in foods. some lab isolates inhib ...201425190588
systemic c3 modulates cd8+ t cell contraction after listeria monocytogenes infection.ag-specific cd8(+) t cell contraction (contraction), which occurs after the resolution of infection, is critical for homeostasis of the immune system. although complement components regulate the primary cd8(+) t cell response, there is insufficient evidence supporting their role in regulating contraction and memory. in this study, we show that c3-deficient (c3(-/-)) mice exhibited significantly less cd8(+) t cell contraction than did wild-type mice postinfection with recombinant listeria monocyt ...201425187659
[host responses to bacterial infections].pathogenic bacteria and host defense system have been evolved by their offense and defense. in vivo research is crucial for elucidation of interactions between them. i have investigated their offence and defense by various standpoints using mouse models of listeria monocytogenes and staphylococcus aureus infections. herein, the results of my research including the roles of endogenous cytokines in host defense, the attenuation of host defense mechanism in obesity and diabetes, the development of ...201425186639
an educationally inspired illustration of two-dimensional quantitative microbiological risk assessment (qmra) and sensitivity analysis.quantitative microbiological risk assessment (qmra) is a structured methodology used to assess the risk involved by ingestion of a pathogen. it applies mathematical models combined with an accurate exploitation of data sets, represented by distributions and - in the case of two-dimensional monte carlo simulations - their hyperparameters. this research aims to highlight background information, assumptions and truncations of a two-dimensional qmra and advanced sensitivity analysis. we believe that ...201425173917
benzalkonium chloride and heavy-metal tolerance in listeria monocytogenes from retail foods.phenotypic and genotypic tolerance in 71 listeria monocytogenes isolates from different varieties of foods to benzalkonium chloride (bc) and cadmium were investigated by susceptibility test and molecular methods. to investigate the role of efflux pumps in bc tolerance, reserpine, an efflux pump inhibitor, was added to the bc tolerant strains. tolerance to bc and cadmium were 26.8% (19/71) and 49.3% (35/71) respectively. strains with bc tolerance were significantly more frequent among those of se ...201425173916
listeria monocytogenes infection in inflammatory bowel disease patients: case series and review of the literature.listeria monocytogenes (lm) is a gram-positive intracellular bacillus that in immunodeficient patients, children, geriatric patients, pregnant women, and even in healthy individuals can cause central nervous system infection, bacteremia, and other clinical manifestations, becoming a relevant pathogen.201425171025
agonistic anti-cd40 enhances the cd8+ t cell response during vesicular stomatitis virus infection.intracellular pathogens are capable of inducing vigorous cd8+ t cell responses. however, we do not entirely understand the factors driving the generation of large pools of highly protective memory cd8+ t cells. here, we studied the generation of endogenous ovalbumin-specific memory cd8+ t cells following infection with recombinant vesicular stomatitis virus (vsv) and listeria monocytogenes (lm). vsv infection resulted in the generation of a large ovalbumin-specific memory cd8+ t cell population, ...201425166494
listeria rhomboencephalitis in a patient on a tumor necrosis factor α inhibitor (etanercept).we describe a case of an 87-year-old woman with rheumatoid arthritis on etanercept who developed subacute encephalopathy. magnetic resonance imaging and blood cultures led to the diagnosis of listeria monocytogenes rhomboencephalitis, which proved to be fatal. postmortem examination of the brain revealed abscesses with extensive necrosis. gram stain showed small gram-positive rods in the necrotic tissue and the wall lining the abscesses. while rhomboencephalitis is a rare entity, and clinical re ...201425160017
listeria monocytogenes is resistant to lysozyme through the regulation, not the acquisition, of cell wall-modifying enzymes.listeria monocytogenes is a gram-positive facultative intracellular pathogen that is highly resistant to lysozyme, a ubiquitous enzyme of the innate immune system that degrades cell wall peptidoglycan. two peptidoglycan-modifying enzymes, pgda and oata, confer lysozyme resistance on l. monocytogenes; however, these enzymes are also conserved among lysozyme-sensitive nonpathogens. we sought to identify additional factors responsible for lysozyme resistance in l. monocytogenes. a forward genetic s ...201425157076
dose response of listeria monocytogenes invasion, fetal morbidity, and fetal mortality after oral challenge in pregnant and nonpregnant mongolian gerbils.listeria monocytogenes is a food-borne pathogen that can result in adverse pregnancy outcomes, such as stillbirth or premature delivery. the mongolian gerbil was recently proposed as the most appropriate small-animal model of listeriosis due to its susceptibility to the same invasion pathways as humans. the objectives of this study were to investigate invasion and adverse pregnancy outcomes in gerbils orally exposed to l. monocytogenes, to compare the dose-response data to those of other animal ...201425156729
potential uptake of escherichia coli o157:h7 and listeria monocytogenes from growth substrate into leaves of salad plants and basil grown in soil irrigated with contaminated water.outbreaks of foodborne illness, resulting from the consumption of fresh produce contaminated with human pathogens, are increasing. potential uptake and persistence of human pathogens within edible parts of consumed fresh vegetables become an important issue in food safety. this study was conducted to assess the potential uptake and internalization of escherichia coli o157:h7 and listeria monocytogenes from an autoclaved substrate into edible parts of basil and baby salad plants (lettuce, cultiva ...201425150671
anti-listerial synergism of leaf essential oil of metasequoia glyptostroboides with nisin in whole, low and skim milks.to examine the individual and synergistic anti-listerial effect of nisin and leaf essential oil of metasequoia glyptostroboides (m. glyptostroboides) against one of the leading foodborne pathogens listeria monocytogenes (l. monocytogenes) atcc 19116 in milk samples.201425149373
antibacterial effect of silver nanoparticles against four foodborne pathogens.there is increased demand for improved disinfection methods due to microorganisms resistant to multiple antimicrobial agents. numerous types of disinfectants are available with different properties; but the proper disinfectant must be carefully selected for any specific application to obtain the desired antimicrobial effect.201425147658
impact of sod on the expression of stress-related genes in listeria monocytogenes 4b g with/without paraquat treatment.listeria monocytogenes is a foodborne pathogen that causes listeriosis. paraquat can generate reactive oxygen species (ros) in cells, which results in oxidative stress. it was first shown that 1 mm of paraquat inhibited the growth rate of a superoxide dismutase (sod)-deletion mutant (∆sod) generated from l. monocytogenes 4b g but not in the wild-type, and induced the expression of other resistance genes (kat, fri, perr, sigb, and reca) as well as sod in the wild type. interestingly, without para ...201425146690
combination of pulsed electric fields, mild heat and essential oils as an alternative to the ultrapasteurization of liquid whole egg.the production of microbiologically safe liquid whole egg (lwe) by industrial ultrapasteurization is restricted by the high thermal sensitivity of lwe components. this research proposes an alternative treatment based on the application of pulsed electric fields (pef) and mild heat, in the presence of natural essential oils (eos) or their individual components (ics). the obtained results indicate that the successive application of pef (25kv/ and 100kj/kg) followed by heat (60°c during 3.5') to lw ...201425146463
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