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proportion of illness acquired by foodborne transmission for nine enteric pathogens in australia: an expert elicitation.estimates of the burden of illness acquired from food inform public health policy and prioritize interventions. a key component of such estimates is the proportion of illnesses that are acquired by foodborne transmission. in view of the shortage of requisite data, these proportions are commonly obtained through a process known as expert elicitation. we report findings from an elicitation process used to assess the importance of the foodborne transmission route for nine pathogens in australia, ci ...201425072416
stability, compatibility and microbiological activity studies of meropenem-clavulanate potassium.meropenem (mem) and clavulanate potassium have been reported to demonstrate highly effective activity against mycobacterium tuberculosis. there have been no reports on research into the complex of these chemotherapeutics concerning their mutually dependent stability or microbiological action on other microorganisms. stability and compatibility studies of mem/clavulanate potassium were conducted by using an hplc-dad method. the antibacterial activity of mem/clavulanate potassium was tested in vit ...201525074659
the rab5-gef function of rin1 regulates multiple steps during listeria monocytogenes infection.listeria monocytogenes is a food-borne pathogenic bacterium that invades intestinal epithelial cells through a phagocytic pathway that relies on the activation of host cell rab5 gtpases. listeria monocytogenes must subsequently inhibit rab5, however, in order to escape lysosome-mediated destruction. relatively little is known about upstream rab5 regulators during l. monocytogenes entry and phagosome escape processes in epithelial cells. here we identify rin1, a ras effector and rab5-directed gua ...201425082076
attenuated listeria monocytogenes reprograms m2-polarized tumor-associated macrophages in ovarian cancer leading to inos-mediated tumor cell lysis.a principal mechanism by which tumors evade immune-mediated elimination is through immunosuppression. previous approaches to tumor immunotherapy have focused on modifying the immunosuppressive environment with immune checkpoint inhibitors, cytokine therapy, and other modalities with the intent to generate t-cell based anti-tumor immunity. we hypothesized that transformation of the suppressive ovarian cancer microenvironment could be achieved by introduction of the attenuated δacta/δinlb strain o ...201425083323
radiation therapy combined with listeria monocytogenes-based cancer vaccine synergize to enhance tumor control in the b16 melanoma model.conceptually, the immune system may profoundly influence the efficacy of radiation therapy. compelling evidence has recently emerged revealing the capacity of local radiation therapy (rt) to induce antitumor immune responses and sparked interest in combining rt with immunotherapy to promote tumor-specific immunity. a listeria monocytogenes (lm)-based cancer vaccine engineered to express tumor-associated antigen has been shown to effectively retard tumor growth by cell-mediated immune mechanisms. ...201425083327
antimicrobial activity of reuterin produced by lactobacillus reuteri on listeria monocytogenes in cold-smoked salmon.lactobacillus reuteri inia p579 was used for the production and purification of reuterin. the purity of reuterin was assessed by high resolution electrospray ionization mass spectrometry (hresims) and nuclear magnetic resonance (nmr) spectroscopy. after purification, reuterin concentration obtained was 1.3 m. the inhibitory activity using escherichia coli k12 as indicator strain was estimated to be 510 au/ml. survival curves in tryptic soy broth revealed that reuterin required to inhibit the gro ...201425084638
efficacy of plant-derived compounds combined with hydrogen peroxide as antimicrobial wash and coating treatment for reducing listeria monocytogenes on cantaloupes.the efficacy of four plant-derived antimicrobials (pdas), namely carvacrol, thymol, β-resorcylic acid, and caprylic acid, with or without hydrogen peroxide (hp), as antimicrobial wash and chitosan based coating for reducing listeria monocytogenes (lm) on cantaloupes was investigated. cantaloupe rind plugs inoculated with lm (10(7) cfu/cm(2)) were washed for 3, 6, 10 min at 25 °c or 1, 3, 5 min at 55 or 65 °c in water, or water containing 2% pdas with or without 2% hp. additionally, inoculated ca ...201425084644
a novel model to assess the efficacy of steam surface pasteurization of cooked surimi gels inoculated with realistic levels of listeria innocua.steam surface pasteurization is a promising decontamination technology for reducing pathogenic bacteria in different stages of food production. the effect of the artificial inoculation type and initial microbial load, however, has not been thoroughly assessed in the context of inactivation studies. in order to optimize the efficacy of the technology, the aim of this study was to design and validate a model system for steam surface pasteurization, assessing different inoculation methods and reali ...201425084647
diversity and distribution of listeria monocytogenes in meat processing plants.listeria monocytogenes is a major concern for the meat processing industry because many listeriosis outbreaks have been linked to meat product consumption. the aim of this study was to elucidate l. monocytogenes diversity and distribution across different spanish meat processing plants. l. monocytogenes isolates (n = 106) collected from food contact surfaces of meat processing plants and meat products were serotyped and then characterised by multilocus sequence typing (mlst). the isolates were s ...201425084653
the effects of competition from non-pathogenic foodborne bacteria during the selective enrichment of listeria monocytogenes using buffered listeria enrichment broth.the growth of listeria monocytogenes during the pathogen specific enrichment of food samples can be limited by the presence of additional microorganisms that are resistant to the selective conditions being applied. if growth is severely limited and minimum post-enrichment threshold levels are not met then the presence of l. monocytogenes may go undetected. several food products were screened for non-pathogenic commensal or spoilage microorganisms that are capable of growth under the conditions c ...201425084660
modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of listeria monocytogenes in cottage cheese.four mathematical models were developed and validated for simultaneous growth of mesophilic lactic acid bacteria from added cultures and listeria monocytogenes, during chilled storage of cottage cheese with fresh- or cultured cream dressing. the mathematical models include the effect of temperature, ph, nacl, lactic- and sorbic acid and the interaction between these environmental factors. growth models were developed by combining new and existing cardinal parameter values. subsequently, the refe ...201425086348
development of double loop-mediated isothermal amplification to detect listeria monocytogenes in food.in this study, a double loop-mediated isothermal amplification (dlamp) based on two target genes hlya and iap was developed for the rapid detection of listeria monocytogenes in food. the results revealed that the detection time and temperature of our dlamp assay for l. monocytogenes were 15 min and 63 °c respectively, with a sensitivity of 10 fg dna of l. monocytogenes per tube. while normal lamp (nlamp) of hlya or iap was 100 fg dna of l. monocytogenes per tube for 45 min and 63 °c. furthermore ...201425086581
short communication: combined antimicrobial activity of reuterin and diacetyl against foodborne pathogens.reuterin (β-hydroxypropionialdehyde) is a broad-spectrum antimicrobial substance produced by some strains of lactobacillus reuteri during anaerobic fermentation of glycerol. some of these strains are able to survive and produce reuterin in cheese and yogurt when added as adjuncts to the starter. similarly, in fermented dairy foods, other inhibitory compounds such as lactic acid and diacetyl are produced during fermentation. in this work, we studied the combined effect of reuterin and diacetyl un ...201425087026
use of antimicrobial films and edible coatings incorporating chemical and biological preservatives to control growth of listeria monocytogenes on cold smoked salmon.the relatively high incidence of listeria monocytogenes in cold smoked salmon (css) is of concern as it is a refrigerated processed food of extended durability (repfed). the objectives of this study were to compare and optimize the antimicrobial effectiveness of films and coatings incorporating nisin (nis) and sodium lactate (sl), sodium diacetate (sd), potassium sorbate (ps), and/or sodium benzoate (sb) in binary or ternary combinations on css. surface treatments incorporating nis (25000 iu/ml) ...201425089272
bacterial maximum non-inhibitory and minimum inhibitory concentrations of different water activity depressing solutes.the nacl mnics (maximum non-inhibitory concentrations) and mics (minimum inhibitory concentrations) for growth of various strains of six bacterial species were determined and then compared with those obtained for seven other solutes. the influence of prior growth conditions on the mnics and mics was also evaluated. no significant changes on the mnics and mics were found among the strains studied within each species. among all factors investigated, only growth phase -for gram-negatives- and growt ...201425090605
genomic characterization and expression analysis of five novel il-17 genes in the pacific oyster, crassostrea gigas.interleukin-17 (il-17) is a proinflammatory cytokine that plays an important role in clearing extracellular bacteria and contributes to the pathology of many autoimmune and allergic conditions. in the present study, five novel il-17 homologs were identified by searching and analyzing the pacific oyster genome. all six cgil-17 members (including a previously reported homolog) contained four conserved cysteines that were used in the formation of disulfide bonds. phylogenetic analysis showed that a ...201425090939
impact of rli87 gene deletion on response of listeria monocytogenes to environmental stress.listeria monocytogenes (lm) is a zoonotic pathogen that widely adapts to various environments. recent studies have found that noncoding rnas (ncrnas) play regulatory roles in lm responses to environmental stress. to understand the role of ncrna rli87 in the response regulation, a rli87 deletion strain lm-δrli87 was constructed by homologous recombination and tested for stress responses to high temperature, low temperature, high osmotic pressure, alcohol, acidity, alkaline and oxidative environme ...201425091276
integrated air stream micromixer for performing bioanalytical assays on a plastic chip.this paper describes the design, functioning and use of an integrated mixer that relies on air flux to agitate microliter entities of fluid in an embedded microfluidic cavity. the system was fabricated from multiple layers of a thermoplastic elastomer and features circuits for both liquid and air supply along with pneumatic valves for process control. internally-dyed polymer particles have been used to visualize flow within the fluid phase during agitation. numerical modelling of the micromixer ...201425091476
fresh-cut pineapple as a new carrier of probiotic lactic acid bacteria.due to the increasing interest for healthy foods, the feasibility of using fresh-cut fruits to vehicle probiotic microorganisms is arising scientific interest. with this aim, the survival of probiotic lactic acid bacteria, belonging to lactobacillus plantarum and lactobacillus fermentum species, was monitored on artificially inoculated pineapple pieces throughout storage. the main nutritional, physicochemical, and sensorial parameters of minimally processed pineapples were monitored. finally, pr ...201425093163
small molecule deubiquitinase inhibitors promote macrophage anti-infective capacity.the global spread of anti-microbial resistance requires urgent attention, and diverse alternative strategies have been suggested to address this public health concern. host-directed immunomodulatory therapies represent one approach that could reduce selection for resistant bacterial strains. recently, the small molecule deubiquitinase inhibitor wp1130 was reported as a potential anti-infective drug against important human food-borne pathogens, notably listeria monocytogenes and noroviruses. util ...201425093325
pediococcus pentosaceus sb83 as a potential probiotic incorporated in a liquid system for vaginal delivery.pediococcus pentosaceus sb83 is a bacteriocinogenic culture having potential use as a vaginal probiotic. the objective of this study was to evaluate the behaviour of p. pentosaceus sb83 incorporated in a liquid system for eventually formulating a gel for vaginal delivery. the vaginal probiotic incorporated into glycerol was able to survive in simulated vaginal fluid at normal vaginal ph (4.2) and at ph of vaginal infections (5.5 and 6.5). the probiotic can be stored at 4 °c for a longer period o ...201425097107
[neonatal bacteremia--frequency, spectrum of organisms and correlation between clinical symptoms and laboratory data for early onset sepsis].improved obstetrical management and evidence-based peripartum antimicrobial therapy in the last decades reduce the frequency of early-onset neonatal sepsis (eons) and improve the outcome. the spectrum of the microrganisms is different according to regions, countries and periods of time. appropriate diagnosis and treatment improve the outcome. however dissociation often occurs between clinical manifestation, laboratory and microbiological findings.201425098106
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 infe ...201425098360
cyclic di-gmp-dependent signaling pathways in the pathogenic firmicute listeria monocytogenes.we characterized key components and major targets of the c-di-gmp signaling pathways in the foodborne pathogen listeria monocytogenes, identified a new c-di-gmp-inducible exopolysaccharide responsible for motility inhibition, cell aggregation, and enhanced tolerance to disinfectants and desiccation, and provided first insights into the role of c-di-gmp signaling in listerial virulence. genome-wide genetic and biochemical analyses of c-di-gmp signaling pathways revealed that l. monocytogenes has ...201425101646
effect of lauric arginate, nisin z, and a combination against several food-related bacteria.the effects of lauric arginate (lae) and nisin z, alone or in combination, on cell damage were investigated against escherichia coli o157:h7, listeria monocytogenes and brochothrix thermosphacta, by scanning electron microscopy (sem) and transmission electron microscopy (tem) observations, efflux of potassium and phosphate ions, and growth inhibition. a combination of lae with nisin z caused severe and dramatic changes in the cytoplasmic membrane and cell lysis of both gram-positive and gram-neg ...201425106040
the first invertebrate rig-i-like receptor (rlr) homolog gene in the pacific oyster crassostrea gigas.retinoic acid-inducible gene i (rig-i)-like receptor (rlr) is a pivotal receptor that detects numerous rna and dna viruses and mediates the innate induction of interferons and pro-inflammatory cytokines upon viral infection. in the present study, we cloned and characterized the first rig-i gene in a marine mollusk, crassostrea gigas, and designated it as cgrig-i. the full-length cgrig-i cdna is 3436 bp, including 5'- and 3'-untranslated regions (utrs) of 93 bp and 286 bp, respectively, and an op ...201425107697
enhanced inactivation of food-borne pathogens in ready-to-eat sliced ham by near-infrared heating combined with uv-c irradiation and mechanism of the synergistic bactericidal action.the objective of the study described in this article was, first, to investigate the effect of the simultaneous application of near-infrared (nir) heating and uv irradiation on inactivation of escherichia coli o157:h7, salmonella enterica serovar typhimurium, and listeria monocytogenes in ready-to-eat (rte) sliced ham and as well as its effect on product quality and, second, to elucidate the underlying mechanisms of the synergistic bactericidal action of nir heating and uv irradiation. with the i ...201525107964
human trophoblasts confer resistance to viruses implicated in perinatal infection.primary human trophoblasts were previously shown to be resistant to viral infection, and able to confer this resistance to nontrophoblast cells. can trophoblasts protect nontrophoblastic cells from infection by viruses or other intracellular pathogens that are implicated in perinatal infection?201425108145
3,4-methylenedioxymethamphetamine (mdma--ecstasy) decreases neutrophil activity through the glucocorticoid pathway and impairs host resistance to listeria monocytogenes infection in mice.ecstasy is the popular name of the abuse drug 3,4-methylenedioxymethamphetamine (mdma) that decreases immunity in animals. the mechanisms that generate such alterations are still controversial. seven independent pharmacological approaches were performed in mice to identify the possible mechanisms underlying the decrease of neutrophil activity induced by mdma and the possible effects of mdma on host resistance to listeria monocytogenes. our data showed that mdma (10 mg kg(-1)) administration decr ...201425113903
listerial rhombencephalitis in an immunocompetent woman.listeriosis usually affects immunocompromised patients including elderly people and pregnant women, but it may also affect otherwise healthy individuals. in our report, we present a case of a rare and very severe form of listeriosis-rhombencephalitis in a 61-year-old female with no history of immunosuppression, who, because of history, clinical picture, and laboratory results as well as negative cultures, was at first diagnosed with viral encephalitis. this paper underlines that listeria monocyt ...201425126431
is the exoproteome important for bacterial pathogenesis? lessons learned from interstrain exoprotein diversity in listeria monocytogenes grown at different temperatures.bacterial exoproteomes vary in composition and quantity among species and within each species, depending on the environmental conditions to which the cells are exposed. this article critically reviews the literature available on exoproteins synthesized by the foodborne pathogenic bacterium listeria monocytogenes grown at different temperatures. the main challenges posed for exoproteome analyses and the strategies that are being used to overcome these constraints are discussed. over thirty exopro ...201425127015
identification, characterization, immobilization of a novel type hydrolase (lmh) from listeria monocytogenes.a novel type of hydrolase (lmh) from listeria monocytogenes was identified, characterized, and immobilized for biotechnological applications. primary sequence analysis indicated that lmh had a catalytic triad (ser(91)-asp(192)-his(222)) with a molecular weight of 27.8 kda. homologs of this enzyme are produced by many gram-positive bacteria including bacillus, staphylococcus, and enterococcus. biochemical properties of lmh were investigated by performing mass spectrometry, dynamic light scatterin ...201525128099
structural and mechanistic insight into the listeria monocytogenes two-enzyme lipoteichoic acid synthesis system.lipoteichoic acid (lta) is an important cell wall component required for proper cell growth in many gram-positive bacteria. in listeria monocytogenes, two enzymes are required for the synthesis of this polyglycerolphosphate polymer. the lta primase ltap(lm) initiates lta synthesis by transferring the first glycerolphosphate (grop) subunit onto the glycolipid anchor and the lta synthase ltas(lm) extends the polymer by the repeated addition of grop subunits to the tip of the growing chain. here, w ...201425128528
cytotoxicity of purified listeriolysin o on mouse and human leukocytes and leukaemia cells.listeriolysin o (llo) is the main virulence factor of listeria monocytogenes and facilitates the intracellular survival of the pathogen. some of its characteristics endorse the growing popularity of llo for use in biotechnology, particularly in the development of novel vaccines. here, we evaluate the use of llo to eradicate leukaemia cells.201425134983
role of pbpd1 in stimulation of listeria monocytogenes biofilm formation by subminimal inhibitory β-lactam concentrations.disinfectant-tolerant listeria monocytogenes biofilms can colonize surfaces that come into contact with food, leading to contamination and, potentially, food-borne illnesses. to better understand the process of l. monocytogenes biofilm formation and dispersal, we screened 1,120 off-patent fda-approved drugs and identified several that modulate listeria biofilm development. among the hits were more than 30 β-lactam antibiotics, with effects ranging from inhibiting (≤50%) to stimulating (≥200%) bi ...201425136010
l. monocytogenes in a cheese processing facility: learning from contamination scenarios over three years of sampling.the aim of this study was to analyze the changing patterns of listeria monocytogenes contamination in a cheese processing facility manufacturing a wide range of ready-to-eat products. characterization of l. monocytogenes isolates included genotyping by pulsed-field gel electrophoresis (pfge) and multi-locus sequence typing (mlst). disinfectant-susceptibility tests and the assessment of l. monocytogenes survival in fresh cheese were also conducted. during the sampling period between 2010 and 2013 ...201425136788
the influence of subminimal inhibitory concentrations of benzalkonium chloride on biofilm formation by listeria monocytogenes.disinfectants, such as benzalkonium chloride (bac), are commonly used to control listeria monocytogenes and other pathogens in food processing plants. prior studies have demonstrated that the resistance to bac of l. monocytogenes was associated with the prolonged survival of three strains of molecular serotype 1/2a in an iberian pork processing plant. because survival in such environments is related to biofilm formation, we hypothesised that the influence of bac on the biofilm formation potentia ...201425136789
[listeria monocytogenes and its relationship with non-biological therapy in inflammatory bowel disease]. 201725138387
antimicrobial light-activated materials: towards application for food and environmental safety.to produce light-activated antimicrobial materials composed of the photodynamic dye phloxine b incorporated into paper or cellulose membranes and to investigate ability of these materials to decrease bacterial loads on their surfaces as well as on food surfaces that were in contact with these materials under illumination with regular white light.201425139147
genipin cross-linked nanocomposite films for the immobilization of antimicrobial agent.cellulose nanocrystal (cnc) reinforced chitosan based antimicrobial films were prepared by immobilizing nisin on the surface of the films. nanocomposite films containing 18.65 μg/cm(2) of nisin reduced the count of l. monocytogenes by 6.73 log cfu/g, compared to the control meat samples (8.54 log cfu/g) during storage at 4 °c in a ready-to-eat (rte) meat system. film formulations containing 9.33 μg/cm(2) of nisin increased the lag phase of l. monocytogenes on meat by more than 21 days, whereas f ...201425140839
antimicrobial and mechanical properties of β-cyclodextrin inclusion with essential oils in chitosan films.chitosan films incorporated with various concentrations of the complex of β-cyclodextrin and essential oils (β-cd/eo) were prepared and investigated for antimicrobial, mechanical, and physical properties. four bacterial strains that commonly contaminate food products were chosen as target bacteria to evaluate the antimicrobial activity of the prepared films. the incorporation of β-cd/eo significantly increased the antimicrobial activities of the chitosan films against escherichia coli, salmonell ...201425141280
choice of reference sequence and assembler for alignment of listeria monocytogenes short-read sequence data greatly influences rates of error in snp analyses.the wide availability of whole-genome sequencing (wgs) and an abundance of open-source software have made detection of single-nucleotide polymorphisms (snps) in bacterial genomes an increasingly accessible and effective tool for comparative analyses. thus, ensuring that real nucleotide differences between genomes (i.e., true snps) are detected at high rates and that the influences of errors (such as false positive snps, ambiguously called sites, and gaps) are mitigated is of utmost importance. t ...201425144537
riboswitches. sequestration of a two-component response regulator by a riboswitch-regulated noncoding rna.riboswitches are ligand-binding elements contained within the 5' untranslated regions of bacterial transcripts, which generally regulate expression of downstream open reading frames. here, we show that in listeria monocytogenes, a riboswitch that binds vitamin b12 controls expression of a noncoding regulatory rna, rli55. rli55, in turn, controls expression of the eut genes, whose products enable ethanolamine utilization and require b12 as a cofactor. defects in ethanolamine utilization, or in it ...201425146292
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
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
repurposing cryptosporidium inosine 5'-monophosphate dehydrogenase inhibitors as potential antibacterial agents.inosine 5'-monophosphate dehydrogenase (impdh) catalyzes the pivotal step in guanine nucleotide biosynthesis. impdh is a target for immunosuppressive, antiviral, and anticancer drugs, but, as of yet, has not been exploited for antimicrobial therapy. we have previously reported potent inhibitors of impdh from the protozoan parasite cryptosporidium parvum (cpimpdh). many pathogenic bacteria, including bacillus anthracis, staphylococcus aureus, and listeria monocytogenes, contain impdhs that should ...201425147601
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
tuberculosis and the risk of infection with other intracellular bacteria: a population-based study.summary persons who develop tuberculosis (tb) may have subtle immune defects that could predispose to other intracellular bacterial infections (icbis). we obtained data on tb and five icbis (chlamydia trachomatis, salmonella spp., shigella spp., yersinia spp., listeria monocytogenes) reported to the tennessee department of health, usa, 2000-2011. incidence rate ratios (irrs) comparing icbis in persons who developed tb and icbis in the tennessee population, adjusted for age, sex, race and ethnici ...201525148655
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
low-shear force associated with modeled microgravity and spaceflight does not similarly impact the virulence of notable bacterial pathogens.as their environments change, microbes experience various threats and stressors, and in the hypercompetitive microbial world, dynamism and the ability to rapidly respond to such changes allow microbes to outcompete their nutrient-seeking neighbors. viewed in that light, the very difference between microbial life and death depends on effective stress response mechanisms. in addition to the more commonly studied temperature, nutritional, and chemical stressors, research has begun to characterize m ...201425149449
recognition of u-rich rna by hfq from the gram-positive pathogen listeria monocytogenes.hfq is a post-transcriptional regulator that binds u- and a-rich regions of srnas and their target mrnas to stimulate their annealing in order to effect translation regulation and, often, to alter their stability. the functional importance of hfq and its rna-binding properties are relatively well understood in gram-negative bacteria, whereas less is known about the rna-binding properties of this riboregulator in gram-positive species. here, we describe the structure of hfq from the gram-positive ...201425150227
listeria monocytogenes meningoencephalitis during the treatment with rituximab and mycophenolate mofetil in a patient with pediatric-onset systemic lupus erythematosus. 201625150501
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
pathogen reduction in minimally managed composting of bovine manure.spread of manure pathogens is of considerable concern due to use of manure for land application. in this study, the effects of four static pile treatment options for bovine manure on die-off of a generic escherichia coli, e. coli o157:h7 surrogate, salmonella senftenberg, salm. typhimurium, and listeria monocytogenes were evaluated. bovine manure spiked with these bacteria were placed in cassettes at the top, middle, and bottom sections of four static pile treatments that reflect minimal changes ...201425151442
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
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
molecular basis for self-assembly of a human host-defense peptide that entraps bacterial pathogens.human α-defensin 6 (hd6) is a 32-aa cysteine-rich peptide of the innate immune system. although hd6 is a member of an antimicrobial peptide family, it exhibits negligible antibacterial activity in vitro. rather, hd6 possesses a unique innate immune mechanism whereby it self-assembles into oligomers that capture pathogens to prevent microbial invasion of the intestinal epithelium and subsequent dissemination. molecular-level understanding for why hd6 functions differently from other human defensi ...201425158166
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
prevalence of major foodborne pathogens in food confiscated from air passenger luggage.the eu has issued several directives and regulations pertaining to the importation of animals and products of animal origin (poao) and veterinary controls on importation. unfortunately, little information is available concerning associated risks and no attempts have been made to collect baseline data on the actual prevalence of zoonotic agents in poao carried by travellers. to meet these challenges the eu recently introduced and financed a research project "promise". its main objectives were to ...201525161012
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 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
physicochemical and antimicrobial properties of citral and quercetin incorporated kafirin-based bioactive films.the aim of this study was to determine the physicochemical and antimicrobial properties of kafirin-based bioactive films incorporating the plant essential oil citral and the polyphenol quercetin. the addition of quercetin and citral both imparted a yellowish colour to the films. the tensile strength of films significantly decreased and elongation at break increased when citral was incorporated, whereas addition of quercetin did not alter these two film parameters. the rate of water vapour transm ...201525172719
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
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
photocatalytic and biocidal activities of novel coating systems of mesoporous and dense tio₂-anatase containing silver nanoparticles.here we describe the development of novel nanostructured coating systems with improved photocatalytic and antibacterial activities. these systems comprise a layer of sio2 followed by a layer of mesoporous or dense tio2-anatase, and doping with silver nanoparticles (ag nps). the coatings were synthesized via a sol-gel technique by combining colloidal ag nps with tio2 and sio2 sols. the photocatalytic activity was studied through methyl orange decomposition under uv light. results showed a great i ...201425175258
a function of diviva in listeria monocytogenes division site selection.the cell division protein diviva influences protein transport via the accessory seca2 secretion route in listeria monocytogenes. in contrast, diviva from the closely related bacterium bacillus subtilis contributes to division site selection via the mincdj system. however, no classical min phenotype, i.e. filamentation and minicell production was observed with a listerial δdiviva mutant. this has prompted the speculation that division site selection is diviva-independent in l. monocytogenes. we a ...201425185533
[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
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
overexpression of the novel mate fluoroquinolone efflux pump fepa in listeria monocytogenes is driven by inactivation of its local repressor fepr.whereas fluoroquinolone resistance mainly results from target modifications in gram-positive bacteria, it is primarily due to active efflux in listeria monocytogenes. the aim of this study was to dissect a novel molecular mechanism of fluoroquinolone resistance in this important human pathogen. isogenic l. monocytogenes clinical isolates bm4715 and bm4716, respectively susceptible and resistant to fluoroquinolones, were studied. mics of norfloxacin and ciprofloxacin were determined in the presen ...201425188450
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
fermentative recovery of lipids and proteins from freshwater fish head waste with reference to antimicrobial and antioxidant properties of protein hydrolysate.effectiveness of fermentation using lactic acid bacteria (lab) for recovering lipids and proteins simultaneously from freshwater fish head (fwh) was evaluated. three different proteolytic lab (pediococcus acidilactici ncim5368, enterococcus faecium ncim5335 and pediococcus acidilactici fd3) isolated from fish processing wastes were employed in the fermentation process. the fermentation conditions involved 10 % (w/w) glucose, 2 % (w/w) nacl and 10 % (v/w) lab cultures at 37 °c. the process result ...201425190843
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
a novel glucose 6-phosphate isomerase from listeria monocytogenes.d-arabinose 5-phosphate isomerases (apis) catalyze the interconversion of d-ribulose 5-phosphate and d-arabinose 5-phosphate (a5p). a5p is an intermediate in the biosynthesis of 3-deoxy-d-manno-octulosonate (kdo), an essential component of lipopolysaccharide, the lipopolysaccharide found in the outer membrane of gram-negative bacteria. the genome of the gram-positive pathogen listeria monocytogenes contains a gene encoding a putative sugar isomerase domain api, q723e8, with significant similarit ...201425194846
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
development of new multilocus variable number of tandem repeat analysis (mlva) for listeria innocua and its application in a food processing plant.listeria innocua is an important hygiene indicator bacterium in food industries because it behaves similar to listeria monocytogenes, which is pathogenic to humans. pfge is often used to characterize bacterial strains and to track contamination source. however, because pfge is an expensive, complicated, time-consuming protocol, and poses difficulty in data sharing, development of a new typing method is necessary. mlva is a technique that identifies bacterial strains on the basis of the number of ...201425198191
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
addition to thermized milk of lactococcus lactis subsp. cremoris m104, a wild, novel nisin a-producing strain, replaces the natural antilisterial activity of the autochthonous raw milk microbiota reduced by thermization.recent research has shown that mild milk thermization treatments routinely used in traditional greek cheese production are efficient to inactivate listeria monocytogenes and other pathogenic or undesirable bacteria, but they also inactivate a great part of the autochthonous antagonistic microbiota of raw milk. therefore, in this study, the antilisterial activity of raw or thermized (63°c, 30 s) milk in the presence or absence of lactococcus lactis subsp. cremoris m104, a wild, novel, nisin a-pro ...201425198589
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
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
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
bacteriological quality of vegetables from organic and conventional production in different areas of korea.foods grown in organic production systems have been described as representing an increased risk to public health compared with foods from conventional production. leafy vegetables (spinach, romaine lettuce, and green sesame leaves) grown in organic and conventional systems were collected from various areas in korea and examined using standard culture methods to compare the microbiological quality of the produce grown in the two agricultural systems. the 354 samples of these leafy vegetables were ...201425198606
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
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
microbiological quality of packaged ice from various sources in georgia.this study determined the microbiological and chemical quality of ice produced and bagged on premises in retail establishments and in free-standing self-service ice vending machines in the state of georgia and compared the results with that from ice produced by manufacturing companies monitored by the international packaged ice association. two hundred fifty bags of packaged ice samples were obtained from retail locations and self-service ice vending machines, along with 25 bags of packaged manu ...201425198846
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
reducing pathogens by using zinc oxide nanoparticles and acetic acid in sheep meat.practical applications of different concentrations (0, 1, 2, 4, 6, and 8 mm) of zinc oxide (zno) suspensions containing 1 % acetic acid were investigated against the pathogenic bacteria listeria monocytogenes, escherichia coli, staphylococcus aureus, and bacillus cereus. zno suspensions (0, 1, 3, 6, and 8 mm) containing acetic acid had a significant inhibitory effect on the growth of l. monocytogenes, e. coli, and s. aureus during 12 h of incubation, and the 8 mm suspensions of zno were the most ...201425198854
[magnetic beads adsorption-pcr detection method of four common foodborne pathogens in food].to evaluate the adsorption capacity of magnetic beads for common foodborne pathogens.201425199281
detection of salmonella spp. by a loop-mediated isothermal amplification (lamp) method targeting bcfd gene.in this study, we developed and validated a loop-mediated isothermal amplification (lamp) assay for salmonella detection targeting bcfd gene, a conserved fimbrial operon gene existing in salmonella. the salmonella lamp assay we developed successfully amplified 44 salmonella strains (14 standard strains and 30 clinical isolates), but none of 9 non-salmonella standard strains (proteus mirabilis, listeria monocytogenes, escherichia coli, pseudomonas aeruginosa, shigella flexneri, shigella sonnei, k ...201425199410
evaluation of nacl, ph, and lactic acid on the growth of shiga toxin-producing escherichia coli in a liquid cheddar cheese extract.a cheddar cheese model system, cheddar cheese extract, was used to examine how different levels of known microbial hurdles (nacl, ph, and lactic acid) in cheddar cheese contribute to inhibition of bacterial pathogens. this knowledge is critical to evaluate the safety of cheddar varieties with altered compositions. the range of levels used covered the lowest and highest level of these factors present in low-sodium, low-fat, and traditional cheddar cheeses. four pathogens were examined in this mod ...201425200778
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
the function of lactic acid bacteria and brine solutions on biogenic amine formation by foodborne pathogens in trout fillets.the influences of lactic acid bacteria and brine solutions on the biogenic amine formation by staphylococcus aureus, escherichia coli, klebsiella pneumoniae, enterococus faecalis, pseudomonas aeruginosa, listeria monocytogenes, aeromonas hydrophila and salmonella paratyphi a in fermented trout fillets were investigated. fish fillets were divided into four groups, group 1 without any lactic acid bacteria inoculation, group 2 and group 3 with different salt concentration inoculated with lactic aci ...201125212358
synergistic and antagonistic effect of lactic acid bacteria on tyramine production by food-borne pathogenic bacteria in tyrosine decarboxylase broth.the effect of lactic acid bacteria (lab) strains on tyramine (tyr) and also other biogenic amines (ba) production by eight common food-borne pathogen (fbp) in tyrosine decarboxylase broth (tdb) was investigated by using a rapid hplc method. significant differences were observed among the fbp strains in ammonia (amn) and ba production apart from tryptamine, histamine (his) and spermine formation (p<0.05). salmonella paratyphi a was characterised as the main amine producer. lab had an important sy ...201125214109
the cyclic dinucleotide c-di-amp is an allosteric regulator of metabolic enzyme function.cyclic di-adenosine monophosphate (c-di-amp) is a broadly conserved second messenger required for bacterial growth and infection. however, the molecular mechanisms of c-di-amp signaling are still poorly understood. using a chemical proteomics screen for c-di-amp-interacting proteins in the pathogen listeria monocytogenes, we identified several broadly conserved protein receptors, including the central metabolic enzyme pyruvate carboxylase (lmpc). biochemical and crystallographic studies of the l ...201425215494
progression to multi-scale models and the application to food system intervention strategies.the aim of this article is to discuss how the systems science approach can be used to optimize intervention strategies in food animal systems. it advocates the idea that the challenges of maintaining a safe food supply are best addressed by integrating modeling and mathematics with biological studies critical to formulation of public policy to address these challenges. much information on the biology and epidemiology of food animal systems has been characterized through single-discipline methods ...201525217407
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
control of listeria monocytogenes in fresh cheese using protective lactic acid bacteria.in the past years, there has been a particular focus on the application of bacteriocins produced by lactic acid bacteria (lab) in controlling the growth of pathogenic bacteria in foods. the aim of this study was to select lab strains with antimicrobial activity, previously isolated from a traditional azorean artisanal cheese (pico cheese), in order to identify those with the greatest potential in reducing listeria monocytogenes in fresh cheese. eight bacteriocin producer strains identified as la ...201425222327
the p60 and nama autolysins from listeria monocytogenes contribute to host colonization and induction of protective memory.inducing long-term protective memory cd8(+) t-cells is a desirable goal for vaccines against intracellular pathogens. however, the mechanisms of differentiation of cd8(+) t-cells into long-lived memory cells capable of mediating protection of immunized hosts remain incompletely understood. we have developed an experimental system using mice immunized with wild type (wt) or mutants of the intracellular bacterium listeria monocytogenes (lm) that either do or do not develop protective memory cd8(+) ...201525225110
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
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
old war, new battle, new fighters! 201525231016
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