| biopreservative efficacy of bacteriocin bacfl31 in raw ground turkey meat in terms of microbiological, physicochemical, and sensory qualities. | the effect of the semi purified bacteriocin bacfl31 at 200 and 400 au/g on the shelf life of refrigerated raw ground turkey meat was investigated. the microbiological, physicochemical, and sensory properties of the meat samples were examined during refrigerated storage. the findings indicated that bacfl31 treatments were effective (p<0.05) against the proliferation of various spoilage microorganisms and suppressed the growth of listeria monocytogenes and salmonella typhimurium. the ph, % met-mb, ... | 2017 | 28659558 |
| physiological and molecular understanding of bacterial polysaccharide monooxygenases. | bacteria have long been known to secrete enzymes that degrade cellulose and chitin. the degradation of these two polymers predominantly involves two enzyme families that work synergistically with one another: glycoside hydrolases (ghs) and polysaccharide monooxygenases (pmos). although bacterial pmos are a relatively recent addition to the known biopolymer degradation machinery, there is an extensive amount of literature implicating pmo in numerous physiological roles. this review focuses on the ... | 2017 | 28659491 |
| lanosterol modulates tlr4-mediated innate immune responses in macrophages. | macrophages perform critical functions in both innate immunity and cholesterol metabolism. here, we report that activation of toll-like receptor 4 (tlr4) in macrophages causes lanosterol, the first sterol intermediate in the cholesterol biosynthetic pathway, to accumulate. this effect is due to type i interferon (ifn)-dependent histone deacetylase 1 (hdac1) transcriptional repression of lanosterol-14α-demethylase, the gene product of cyp51a1. lanosterol accumulation in macrophages, because of ei ... | 2017 | 28658622 |
| e3 ubiquitin ligase znrf4 negatively regulates nod2 signalling and induces tolerance to mdp. | optimal regulation of the innate immune receptor nucleotide-binding oligomerization domain-containing protein 2 (nod2) is essential for controlling bacterial infections and inflammatory disorders. chronic nod2 stimulation induces non-responsiveness to restimulation, termed nod2-induced tolerance. although the levels of the nod2 adaptor, rip2, are reported to regulate both acute and chronic nod2 signalling, how rip2 levels are modulated is unclear. here we show that znrf4 induces k48-linked ubiqu ... | 2017 | 28656966 |
| listeria monocytogenes cytosolic metabolism promotes replication, survival, and evasion of innate immunity. | listeria monocytogenes, the causative agent of listeriosis, is an intracellular pathogen that is exquisitely evolved to survive and replicate in the cytosol of eukaryotic cells. eukaryotic cells typically restrict bacteria from colonising the cytosol, likely through a combination of cell autonomous defences, nutritional immunity, and innate immune responses including induction of programmed cell death. this suggests that l. monocytogenes and other professional cytosolic pathogens possess unique ... | 2017 | 28656691 |
| listeria placental infection. | the gram-positive facultative intracellular bacterium listeria monocytogenes is the causative agent of listeriosis, a severe food-borne infection. pregnant women are at risk of contracting listeriosis, which can potentially lead to miscarriage, stillbirth, preterm birth, and congenital neonatal infections. while other systemic bacterial infections may result in adverse pregnancy outcomes at comparable frequencies, l. monocytogenes has particular notoriety because fetal complications largely occu ... | 2017 | 28655824 |
| hepcidin-(in)dependent mechanisms of iron metabolism regulation during infection by listeria and salmonella. | during bacterial infection, the pathogenic agent and the host battle for iron, due to its importance for fundamental cellular processes. however, iron redistribution and sequestration during infection can culminate in anemia. although hepcidin has been recognized as the key regulator of iron metabolism, in some infections its levels remain unaffected, suggesting the involvement of other players in iron metabolism deregulation. in this work, we use a mouse model to elucidate the main cellular and ... | 2017 | 28652306 |
| a nationwide outbreak of listeriosis associated with cold-cuts, sweden 2013-2014. | in january 2014, the public health agency of sweden noticed an increase in listeriosis cases. isolates from 10 cases had identical pulsed field gel electrophoresis (pfge) profiles, suggesting a common source. we investigated the outbreak to identify the source and stop transmission. we looked for cases in 2013-2014 and also compared cases notified after february 2014 to randomly selected controls. we surveyed food items consumed two weeks prior to symptom onset. listeria monocytogenes isolates f ... | 2017 | 28649304 |
| real-time whole-genome sequencing for surveillance of listeria monocytogenes, france. | during 2015-2016, we evaluated the performance of whole-genome sequencing (wgs) as a routine typing tool. its added value for microbiological and epidemiologic surveillance of listeriosis was compared with that for pulsed-field gel electrophoresis (pfge), the current standard method. a total of 2,743 listeria monocytogenes isolates collected as part of routine surveillance were characterized in parallel by pfge and core genome multilocus sequence typing (cgmlst) extracted from wgs. we investigat ... | 2017 | 28643628 |
| antibacterial efficacy of nisin, bacteriophage p100 and sodium lactate against listeria monocytogenes in ready-to-eat sliced pork ham. | the effectiveness of bacteriophage p100, nisin and sodium lactate, individually and in combination, in inhibiting listeria monocytogenes in ready-to-eat pork ham slices was assessed. the antimicrobials were applied to the surfaces of ready-to-eat pork ham slices, which were inoculated with a mixture of l. monocytogenes. among the individual antimicrobial treatments, bacteriophage p100 was the most effective, decreasing l. monocytogenes to undetectable levels at zero and 72h post-infection. sodiu ... | 2017 | 28641956 |
| core-shell pla-pva porous microparticles as carriers for bacteriocin nisin. | this work is focused on preparation of novel porous type of core-shell-structured microparticles based on polylactide (shell) and poly(vinyl alcohol) cross-linked with glutaric acid (ga) (core) prepared by water-in-oil-in-water solvent evaporation technique. the microparticle systems were used as delivery systems for immobilisation of model antibacterial agent - nisin. the effect of cross-linking and the initial amount of nisin on their morphology was investigated using scanning electron microsc ... | 2017 | 28635414 |
| influence of lactic acid and post-treatment recovery time on the heat resistance of listeria monocytogenes. | the aim of this study was to evaluate the effect of lactic acid (la) with and without organic material at various post-treatment recovery times on the heat resistance of listeria monocytogenes (lm). la decreased lm numbers; however, the effect was remarkably attenuated by the presence of organic matter. five strains of lm were treated with la and the listericidal effects were compared. the effect of la varied depending on the strain, with ≥3.0% (w/w) la required to kill the lm strains in a short ... | 2017 | 28633051 |
| changing us population demographics: what does this mean for listeriosis incidence and exposure? | listeria monocytogenes is an important cause of foodborne illness hospitalization, fetal loss, and death in the united states. listeriosis incidence rate varies significantly among population subgroups with pregnant women, older persons, and the hispanic population having increased relative risks compared with the other subpopulations. using estimated rates of listeriosis per subpopulation based on foodnet data from 2004 to 2009, we evaluate the expected number of cases and incidence rates of li ... | 2017 | 28632414 |
| listeriolysin o: from bazooka to swiss army knife. | listeria monocytogenes (lm) is a gram-positive facultative intracellular pathogen. infections in humans can lead to listeriosis, a systemic disease with a high mortality rate. one important mechanism of lm dissemination involves cell-to-cell spread after bacteria have entered the cytosol of host cells. listeriolysin o (llo; encoded by the hly gene) is a virulence factor present in lm that plays a central role in the cell-to-cell spread process. llo is a member of the cholesterol-dependent cytoly ... | 2017 | 28630160 |
| crmp-1 enhances evl-mediated actin elongation to build lamellipodia and the actin cortex. | cells can control actin polymerization by nucleating new filaments or elongating existing ones. we recently identified crmp-1 as a factor that stimulates the formation of listeria monocytogenes actin comet tails, thereby implicating it in actin assembly. we now show that crmp-1 is a major contributor to actin assembly in epithelial cells, where it works with the ena/vasp family member evl to assemble the actin cytoskeleton in the apical cortex and in protruding lamellipodia. crmp-1 and evl bind ... | 2017 | 28630144 |
| listeria-vectored vaccine expressing the mycobacterium tuberculosis 30 kda major secretory protein via the constitutively active prfa* regulon boosts bcg efficacy against tuberculosis. | a potent vaccine against tuberculosis, one of the world's deadliest diseases, is needed to enhance the immunity of people worldwide, most of whom have been vaccinated with the partially effective bcg vaccine. here we investigate novel live attenuated recombinant listeria monocytogenes (rlm) vaccines expressing the mycobacterium tuberculosis (mtb) 30 kda major secretory protein (r30/ag85b) (rlm30) as heterologous booster vaccines in animals primed with bcg. using three attenuated lm vectors, rlm ... | 2017 | 28630063 |
| prevalence and serotype distribution of listeria monocytogenes isolated from foods in montevideo-uruguay. | the aim of this work was to study the prevalence of listeria monocytogenes in foods obtained in retail shops and food industries located in montevideo-uruguay, and to identify the serogroups of the obtained isolates. three-thousand one-hundred and seventy-five food samples (frozen, deli meats, ready-to-eat and cheese) were analyzed. the obtained isolates were serogrouped by multiplex pcr and serotyped by conventional procedure. genetic comparisons were performed using pulsed-field gel electropho ... | 2017 | 28629969 |
| a multiplex rt-pcr assay for s. aureus, l. monocytogenes, and salmonella spp. detection in raw milk with pre-enrichment. | this study firstly developed a multiplex real-time pcr (rt-pcr) technique combined with a pre-enrichment step to simultaneously detect staphylococcus aureus (s. aureus), listeria monocytogenes (l. monocytogenes) and salmonella spp. in raw milk and the dairy farm environment (feces, soil, feed, water) in one reaction. brain heart infusion (bhi) broth was selected for the enrichment step to increase the density of the target bacteria by using an incubation of 4 h before multiplex rt-pcr. the resul ... | 2017 | 28620364 |
| full-genome sequence of listeria monocytogenes strain h34, isolated from a newborn with sepsis in uruguay. | the foodborne pathogen listeria monocytogenes causes severe disease mainly in the vulnerable populations of the young, old, pregnant, and immunocompromised. here, we present the genome sequence of l. monocytogenes h34, a serotype 1/2b, lineage i, sequence type 489 (st489) strain, isolated from a neonatal sepsis case in uruguay. | 2017 | 28619811 |
| whole genome sequencing analyses of listeria monocytogenes that persisted in a milkshake machine for a year and caused illnesses in washington state. | in 2015, in addition to a united states multistate outbreak linked to contaminated ice cream, another outbreak linked to ice cream was reported in the pacific northwest of the united states. it was a hospital-acquired outbreak linked to milkshakes, made from contaminated ice cream mixes and milkshake maker, served to patients. here we performed multiple analyses on isolates associated with this outbreak: pulsed-field gel electrophoresis (pfge), whole genome single nucleotide polymorphism (snp) a ... | 2017 | 28619007 |
| development of biopolymer composite films using a microfluidization technique for carboxymethylcellulose and apple skin particles. | biopolymer films based on apple skin powder (asp) and carboxymethylcellulose (cmc) were developed with the addition of apple skin extract (ase) and tartaric acid (ta). asp/cmc composite films were prepared by mixing cmc with asp solution using a microfluidization technique to reduce particle size. then, various concentrations of ase and ta were incorporated into the film solution as an antioxidant and an antimicrobial agent, respectively. fourier transform infrared (ftir), optical, mechanical, w ... | 2017 | 28617325 |
| influence of food characteristics and food additives on the antimicrobial effect of garlic and oregano essential oils. | utilization of essential oils (eos) as antimicrobial agents against foodborne disease has gained importance, for their use as natural preservatives. since potential interactions between eos and food characteristics may affect their antimicrobial properties, the present work studies the influence of fat, protein, ph, aw and food additives on the antimicrobial effect of oregano and garlic eos against salmonella spp. and listeria monocytogenes. results showed that protein, ph, aw, presence of beef ... | 2017 | 28604598 |
| how the study of listeria monocytogenes has led to new concepts in biology. | the opportunistic intracellular bacterial pathogen listeria monocytogenes has in 30 years emerged as an exceptional bacterial model system in infection biology. research on this bacterium has provided considerable insight into how pathogenic bacteria adapt to mammalian hosts, invade eukaryotic cells, move intracellularly, interfere with host cell functions and disseminate within tissues. it also contributed to unveil features of normal host cell pathways and unsuspected functions of previously k ... | 2017 | 28604108 |
| persistent listeria monocytogenes strains isolated from mussel production facilities form more biofilm but are not linked to specific genetic markers. | contamination of mussels with the human pathogen listeria monocytogenes occurs during processing in the factory, possibly from bacteria persisting in the factory's indoor and outdoor areas. in this study, a selection of persistent (n=8) and sporadic (n=8) l. monocytogenes isolates associated with mussel-processing premises in new zealand were investigated for their phenotypic and genomic characteristics. to identify traits that favour or contribute to bacterial persistence, biofilm formation, he ... | 2017 | 28599174 |
| comparison of the in vitro activity of ampicillin and moxifloxacin against listeria monocytogenes at achievable concentrations in the central nervous system. | the aim of this study was to compare the in vitro activity of ampicillin and moxifloxacin against six isolates selected from 154 invasive clinical isolates of listeria monocytogenes and evaluate their intra- and extracellular activities with achievable central nervous system concentrations obtained using monte carlo simulations with conventional and unconventional dosages. | 2017 | 28598305 |
| mathematical model of interaction between bacteriocin-producing lactic acid bacteria and listeria. part 1: steady states and thresholds. | mathematical modeling is an important tool to assessing quantitative conjectures and to answer specific questions. in the modeling, we assume that a competitor represented by a lactic acid bacterium produces antimicrobial compounds (substances that kill microorganisms or inhibit their growth), such as lactic acid and bacteriocins, with some cost to its own growth. bacteriocins are protein compounds with antimicrobial effect against related species and bacteria such as listeria monocytogenes, whi ... | 2017 | 28597170 |
| inhibition strategies of listeria monocytogenes biofilms-current knowledge and future outlooks. | there is an increasing trend in the food industry on the listeria monocytogenes biofilm formation and inhibition. this is attributed to its easy survival on contact surfaces, resistance to disinfectants or antibiotics and growth under the stringent condition used for food processing and preservation thereby leading to food contamination products by direct or indirect exposure. though, there is a lack of conclusive evidences about the mechanism of biofilm formation, in this review, the concept of ... | 2017 | 28594071 |
| commensal microbes provide first line defense against listeria monocytogenes infection. | listeria monocytogenes is a foodborne pathogen that causes septicemia, meningitis and chorioamnionitis and is associated with high mortality. immunocompetent humans and animals, however, can tolerate high doses of l. monocytogenes without developing systemic disease. the intestinal microbiota provides colonization resistance against many orally acquired pathogens, and antibiotic-mediated depletion of the microbiota reduces host resistance to infection. here we show that a diverse microbiota mark ... | 2017 | 28588016 |
| longitudinal monitoring of listeria monocytogenes and listeria phages in seafood processing environments in thailand. | listeria monocytogenes is a foodborne pathogen commonly found in environments of seafood processing, thus presenting a challenge for eradication from seafood processing facilities. monitoring the prevalence and subtype diversity of l. monocytogenes together with phages that are specific to listeria spp. ("listeria phages") will provide knowledge on the bacteria-phage ecology in food processing plants. in this work, a total of 595 samples were collected from raw material, finished seafood product ... | 2017 | 28576358 |
| empiric listeria monocytogenes antibiotic coverage for febrile infants (age, 0-90 days). | | 2017 | 28574538 |
| genome-wide-analyses of listeria monocytogenes from food-processing plants reveal clonal diversity and date the emergence of persisting sequence types. | whole genome sequencing is increasing used in epidemiology, e.g. for tracing outbreaks of food-borne diseases. this requires in-depth understanding of pathogen emergence, persistence and genomic diversity along the food production chain including in food processing plants. we sequenced the genomes of 80 isolates of listeria monocytogenes sampled from danish food processing plants over a time-period of 20 years, and analysed the sequences together with 10 public available reference genomes to adv ... | 2017 | 28574206 |
| draft genome sequences of listeria monocytogenes, isolated from fresh leaf vegetables in owerri city, nigeria. | here, we report the draft genome sequences of three listeria monocytogenes isolates from fresh leaves collected in nigeria, belonging to sequence types st5 and st155 (sublineages sl5 and sl155, respectively). | 2017 | 28572306 |
| curcumin promotes the clearance of listeria monocytogenes both in vitro and in vivo by reducing listeriolysin o oligomers. | the pore-forming toxin listeriolysin o (llo), an essential virulence factor that is secreted by listeria monocytogenes (l. monocytogenes), is responsible for bacterial breaching at the phagosomal membranes and subsequent release into the cytoplasm; it cannot be recognized by the host immune system. the vital role that llo plays in bacterial pathogenicity and evading host immune clearance makes this virulence a promising target for addressing l. monocytogenes infection. in this study, we hypothes ... | 2017 | 28567044 |
| impact of nutrient restriction on the structure of listeria monocytogenes biofilm grown in a microfluidic system. | biofilm formation by the pathogen listeria monocytogenes is a major concern in food industries. the aim of this work was to elucidate the effect of nutrient limitation on both biofilm architecture and on the viability of the bacteria in microfluidic growth conditions. biofilm formation by two l. monocytogenes strains was performed in a rich medium (bhi) and in a 10-fold diluted bhi (bhi/10) at 30°c for 24 h by using both static conditions and the microfluidic system bioflux. in dynamic condition ... | 2017 | 28567031 |
| naïve helper t cells with high cd5 expression have increased calcium signaling. | the adaptive immune response is orchestrated by t helper cells and their function is dependent upon interactions between the t cell receptor (tcr), peptide mhc (pmhc) and co-receptors. tcr-pmhc interactions initiate calcium signaling cascades which determine t cell activation, survival, proliferation and differentiation. cd5 is a co-receptor that plays an important role in regulating t cell signaling and fate during thymocyte education. cd5 surface expression on mature single positive thymocytes ... | 2017 | 28562659 |
| deciphering the landscape of host barriers to listeria monocytogenes infection. | listeria monocytogenes is a common food-borne pathogen that can disseminate from the intestine and infect multiple organs. here, we used sequence tag-based analysis of microbial populations (stamp) to investigate lmonocytogenes population dynamics during infection. we created a genetically barcoded library of murinized lmonocytogenes and then used deep sequencing to track the pathogen's dissemination routes and quantify its founding population (nb) sizes in different organs. we found that the pa ... | 2017 | 28559314 |
| whole genome and core genome multilocus sequence typing and single nucleotide polymorphism analyses of listeria monocytogenes associated with an outbreak linked to cheese, united states, 2013. | epidemiological findings of a listeriosis outbreak in 2013 implicated hispanic-style cheese produced by company a, and pulsed-field gel electrophoresis (pfge) and whole genome sequencing (wgs) were performed on clinical isolates and representative isolates collected from company a cheese and environmental samples during the investigation. the results strengthened the evidence for cheese as the vehicle. surveillance sampling and wgs three months later revealed that the equipment purchased by comp ... | 2017 | 28550058 |
| erratum: uncovering listeria monocytogenes hypervirulence by harnessing its biodiversity. | | 2017 | 28546578 |
| the absence of tnf permits myeloid arginase 1 expression in experimental l. monocytogenes infection. | during an immune response inflammatory macrophages with their wide variety of effector mechanisms including the expression of inducible nitric oxide synthase play an important part in the defense against invading pathogens. the inflammatory phenotype requires the presence of tnf which suppresses alternative activation. in the bacterial listeria monocytogenes infection model inflammatory macrophages are crucial for protection. after infection, tnf-deficient hosts have a similar number of splenic ... | 2017 | 28545808 |
| down regulation of macrophage ifngr1 exacerbates systemic l. monocytogenes infection. | interferons (ifns) target macrophages to regulate inflammation and resistance to microbial infections. the type ii ifn (ifnγ) acts on a cell surface receptor (ifngr) to promote gene expression that enhance macrophage inflammatory and anti-microbial activity. type i ifns can dampen macrophage responsiveness to ifnγ and are associated with increased susceptibility to numerous bacterial infections. the precise mechanisms responsible for these effects remain unclear. type i ifns silence macrophage i ... | 2017 | 28542482 |
| invasive listeria monocytogenes gastroenteritis leading to stupor, bacteremia, fever, and diarrhea: a rare life-threatening condition. | listeria monocytogenes is a gram-positive, rod-shaped organism that can cause serious infections such as meningitis, invasive gastroenteritis, and endocarditis. every year 1600 people in the united states are affected, with significant mortality of 260 people annually. listeria gastroenteritis has the third highest mortality rate among all the food-borne infection. invasive listeriosis most commonly affect pregnant women, those in extremes of ages, people with comorbid diseases, and people with ... | 2017 | 28540315 |
| listeriosis during pregnancy. | listeriosis is a rare foodborne illness caused by listeria monocytogenes. it can be transmitted by consuming contaminated ready-to-eat food, long shelf-life products, deli meats, and soft cheeses. listeria has a predilection to affect immunocompromised patients, elderly people, pregnant women and neonates. in particular, pregnant women are at ~18 times greater risk of infection than general population due to specific pregnancy-related suppressed cell-mediated immunity and placental tropism of l. ... | 2017 | 28536811 |
| listeria monocytogenes bacteraemia over an 11-year period: clinical and epidemiologic characteristics in the south area of madrid. | | 2017 | 28527675 |
| effects of parsley extract powder as an alternative for the direct addition of sodium nitrite in the production of mortadella-type sausages - impact on microbiological, physicochemical and sensory aspects. | increasing concern about chemical additives in processed meat has led to an increased market of uncured and alternatively cured meat products. however, the use of vegetable extracts or the exclusion of curing salt may increase the risk of greater bacterial growth and alteration of several physicochemical parameters. therefore, in this study mortadella-type sausages, manufactured with 1.07 (v3), 2.14 (v4) and 4.29 (v5) g parsley extract powder/kg sausage meat were produced. these sausage variants ... | 2017 | 28527368 |
| a novel role of listeria monocytogenes membrane vesicles in inhibition of autophagy and cell death. | bacterial membrane vesicle (mv) production has been mainly studied in gram-negative species. in this study, we show that listeria monocytogenes, a gram-positive pathogen that causes the food-borne illness listeriosis, produces mvs both in vitro and in vivo. we found that a major virulence factor, the pore-forming hemolysin listeriolysin o (llo), is tightly associated with the mvs, where it resides in an oxidized, inactive state. previous studies have shown that llo may induce cell death and auto ... | 2017 | 28516064 |
| isolation and characterization of listeria phages for control of growth of listeria monocytogenes in milk. | in this study, two listeria bacteriophages, lmp1 and lmp7, were isolated from chicken feces as a means of biocontrol of l. monocytogenes. both bacteriophages had a lytic effect on l. monocytogenes atcc 7644, 15313, 19114, and 19115. phages lmp1 and lmp7 were able to inhibit the growth of l. monocytogenes atcc 7644 and 19114 in tryptic soy broth at 10°c and 30°c. nevertheless, lmp1 was more effective than lmp7 at inhibiting l. monocytogenes atcc 19114. on the contrary, lmp7 was more effective tha ... | 2017 | 28515656 |
| assessment of microbial and radioactive contaminations in korean cold duck meats and electron-beam application for quality improvement. | animal-origin food products pose serious threat to public food safety due to high microbial loads. the microbial and radioactive contaminations in commercial cold duck meat products were evaluated. ten different lots of commercial samples (c1-c10) were classified based on type and smoking process. all samples were highly contaminated (< 4-7 log cfu/g) with total aerobic bacteria (tab), yeasts and molds (y&m), and 7 samples (c1-c7) were positive for coliforms. furthermore, three samples were cont ... | 2017 | 28515653 |
| unusual listeria monocytogenes peritonitis in peritoneal dialysis patient with liver cirrhosis: a case report and review of literature. | spontaneous listeria peritonitis is well described in liver failure, but is uncommon in peritoneal dialysis patients. atypical cases where peritonitis symptoms develop after systemic manifestations are rare and challenging for diagnostic. a 57-year-old peritoneal dialysis patient with history of ethylic cirrhosis was admitted after epileptic seizure. on admission, patient was soporous without signs of peritonitis and meningitis. patient's peritoneal effluent was clear, with normal leukocytes. cr ... | 2017 | 28509139 |
| tetr-dependent gene regulation in intracellular listeria monocytogenes demonstrates the spatiotemporal surface distribution of acta. | to enable specific and tightly controlled gene expression both in vitro and during the intracellular lifecycle of the pathogen listeria monocytogenes, a tetr-dependent genetic induction system was developed. highest concentration of cytoplasmic tetr and best repression of teto-controlled genes was obtained by tetr expression from the synthetic promoter pt17 . anhydrotetracycline (atc) as inducer permitted concentration-dependent, fine-tuned expression of genes under control of the teto operator ... | 2017 | 28508453 |
| limited colonization undermined by inadequate early immune responses defines the dynamics of decidual listeriosis. | the bacterial pathogen listeria monocytogenes causes foodborne systemic disease in pregnant women, which can lead to preterm labor, stillbirth, or severe neonatal disease. colonization of the maternal decidua appears to be an initial step in the maternal component of the disease as well as bacterial transmission to the placenta and fetus. host-pathogen interactions in the decidua during this early stage of infection remain poorly understood. here, we assessed the dynamics of l. monocytogenes inf ... | 2017 | 28507070 |
| spontaneous bacterial peritonitis due to listeria monocytogenes: always to be remembered. | | 2017 | 28502590 |
| identification of a major listeria monocytogenes outbreak clone linked to soft cheese in northern italy - 2009-2011. | molecular subtyping and enhanced surveillance in lombardy region identified a cluster of possibly related listeriosis cases from 2006 to 2010. this cluster grouped 31 isolates that belonged to serotype 1/2a and sequence type 38 (st38) as defined by multilocus sequence typing (mlst). | 2017 | 28499357 |
| mtorc1 regulates mannose-6-phosphate receptor transport and t-cell vulnerability to regulatory t cells by controlling kinesin kif13a. | mannose-6-phosphate receptor (m6pr) that facilitates cellular uptake of m6p-bearing proteins, including serine-protease granzyme-b (gzm-b) has an important role in t-cell activation, migration and contraction. however, molecular mechanisms controlling m6pr expression in t cells remain poorly understood. here, we show that m6pr expression on t cells is distinctively controlled by two common γ-chain cytokines interleukin-2 (il-2) and il-7, and the differential m6pr expression is not caused by an a ... | 2017 | 28496990 |
| genome sequences of listeria monocytogenes strains with resistance to arsenic. | listeria monocytogenes frequently exhibits resistance to arsenic. we report here the draft genome sequences of eight genetically diverse arsenic-resistant l. monocytogenes strains from human listeriosis and food-associated environments. the availability of these genomes will help elucidate the role of heavy-metal resistance in the ecology of l. monocytogenes. | 2017 | 28495780 |
| complete genome sequences of 12 isolates of listeria monocytogenes belonging to serotypes 1/2a, 1/2b, and 4b obtained from food products and food-processing environments in canada. | listeria monocytogenes is the etiological agent for an often fatal foodborne illness known as listeriosis. here, we present the complete genome sequences of 12 l. monocytogenes isolates representing the three most common serotypes of this pathogen (1/2a, 1/2b, and 4b), collected in canada from different food products and environmental sources. | 2017 | 28495767 |
| draft genome sequences of 25 listeria monocytogenes isolates associated with human clinical listeriosis in ireland. | listeria monocytogenes is a gram-positive opportunistic pathogen that is the causative agent of listeriosis. here, we report the draft genome sequences of 25 l. monocytogenes strains isolated from patients with clinical listeriosis in the republic of ireland between 2013 and 2015. | 2017 | 28495762 |
| listeria endocarditis: a diagnostic challenge. | a 74-year-old hemodialysis patient with a history of an atrial septum defect closure, coronary bypass surgery, and a st. jude aortic prosthetic valve was diagnosed with pneumonia and volume overload. blood cultures were positive for listeria monocytogenes, and amoxicillin was given for 2 weeks. immediately after discontinuation of amoxicillin, fever relapsed. transthoracic and transesophageal echocardiography showed no sign of endocarditis. given the fever relapse and 3 positive minor duke crite ... | 2017 | 28491879 |
| characteristics and outcome of spontaneous bacterial meningitis in patients with cancer compared to patients without cancer. | in cancer patients, who are frequently immunocompromised, bacterial meningitis (bm) can be a severe complication, with a different presentation, etiology, and course, compared to patients without cancer. our objective is to compare the characteristics and outcomes of bm in patients with and without cancer. a single-center, prospective observational cohort study, conducted between 1982 and 2012, in a tertiary university hospital in barcelona (spain). the main outcome measure is in-hospital mortal ... | 2017 | 28489800 |
| analysis of listeria using exogenous volatile organic compound metabolites and their detection by static headspace-multi-capillary column-gas chromatography-ion mobility spectrometry (shs-mcc-gc-ims). | listeria monocytogenes is a gram-positive bacterium and an opportunistic food-borne pathogen which poses significant risk to the immune-compromised and pregnant due to the increased likelihood of acquiring infection and potential transmission of infection to the unborn child. conventional methods of analysis suffer from either long turn-around times or lack the ability to discriminate between listeria spp. reliably. this paper investigates an alternative method of detecting listeria spp. using t ... | 2017 | 28484808 |
| suppression of autoimmune demyelinating disease by preferential stimulation of cns-specific cd8 t cells using listeria-encoded neuroantigen. | cd8 t-cells predominate in cns lesions of ms patients and display oligoclonal expansion. however, the role of myelin-specific cd8 t-cells in disease remains unclear, with studies showing protective and pathogenic roles in eae. we demonstrated a disease-suppressive function for cns-specific cd8 t-cells in a model where the antigen is exogenously administered in vivo and used for in vitro activation. to probe the nature of the cd8 response elicited by endogenously presented myelin antigens in vivo ... | 2017 | 28484224 |
| label-free immuno-sensors for the fast detection of listeria in food. | foodborne diseases are a major concern for both food industry and health organizations due to the economic costs and potential threats for human lives. for these reasons, specific regulations impose the research of pathogenic bacteria in food products. nevertheless, current methods, references and alternatives, take up to several days and require many handling steps. in order to improve pathogen detection in food, we developed an immune-sensor, based on surface plasmon resonance imaging (spri) a ... | 2017 | 28478556 |
| a novel typing method for listeria monocytogenes using high-resolution melting analysis (hrma) of tandem repeat regions. | listeria monocytogenes, which is responsible for causing food poisoning known as listeriosis, infects humans and animals. widely distributed in the environment, this bacterium is known to contaminate food products after being transmitted to factories via raw materials. to minimize the contamination of products by food pathogens, it is critical to identify and eliminate factory entry routes and pathways for the causative bacteria. high resolution melting analysis (hrma) is a method that takes adv ... | 2017 | 28475927 |
| inll from listeria monocytogenes is involved in biofilm formation and adhesion to mucin. | the bacterial etiological agent of listeriosis, listeria monocytogenes, is an opportunistic intracellular foodborne pathogen. the infection cycle of l. monocytogenes is well-characterized and involves several key virulence factors, including internalins a and b. while 35 genes encoding internalins have been identified in l. monocytogenes, less than half of them have been characterized as yet. focusing on lmo2026, it was shown this gene encodes a class i internalin, inll, exhibiting domains poten ... | 2017 | 28473809 |
| listeria monocytogenes meningitis: pcr multiplex diagnosis. | | 2017 | 28473173 |
| comparative genomics of human and non-human listeria monocytogenes sequence type 121 strains. | the food-borne pathogen listeria (l.) monocytogenes is able to survive for months and even years in food production environments. strains belonging to sequence type (st)121 are particularly found to be abundant and to persist in food and food production environments. to elucidate genetic determinants characteristic for l. monocytogenes st121, we sequenced the genomes of 14 st121 strains and compared them with currently available l. monocytogenes st121 genomes. in total, we analyzed 70 st121 geno ... | 2017 | 28472116 |
| lentinan from shiitake selectively attenuates aim2 and non-canonical inflammasome activation while inducing pro-inflammatory cytokine production. | lentinan extracted from shiitake (lentinula edodes) is a β-glucan that has been reported as an intravenous anti-tumor polysaccharide via enhancement of the host immune system. in this study, we determined the effect of lentinan on inflammasome activation, a multi-protein platform, in myeloid cells. mouse bone marrow-derived macrophages were treated with lentinan with/without inflammasome triggers, and maturation of interleukin (il)-1β, il-18, or caspase-1 was measured as a readout of inflammasom ... | 2017 | 28465544 |
| a clade of listeria monocytogenes serotype 4b variant strains linked to recent listeriosis outbreaks associated with produce from a defined geographic region in the us. | four listeriosis incidences/outbreaks, spanning 19 months, have been linked to listeria monocytogenes serotype 4b variant (4bv) strains. three of these incidents can be linked to a defined geographical region, while the fourth is likely to be linked. in this study, whole genome sequencing (wgs) of strains from these incidents was used for genomic comparisons using two approached. the first was jspecies tetramer, which analyzed tetranucleotide frequency to assess relatedness. the second, the cfsa ... | 2017 | 28464038 |
| analysis of process factors of dry fermented salami to control listeria monocytogenes. | challenge tests are a clear opportunity for manufacturers interested in the evaluation of their management system with the aim to reduce the spread of foodborne pathogens. this is a main concern especially in ready-to-eat food in relation to the risk associated with listeria monocytogenes. for small and medium-scale food industry the manufacturing practices and products formulation are characterised by a wider variability and poor repeatability. the use of ad hoc challenge test and the compariso ... | 2017 | 28462203 |
| host serine/threonine kinases mtor and protein kinase c-α promote inlb-mediated entry of listeria monocytogenes. | the bacterial pathogen listeria monocytogenes causes foodborne illnesses resulting in gastroenteritis, meningitis, or abortion. listeria induces its internalization into some human cells through interaction of the bacterial surface protein inlb with the host receptor tyrosine kinase met. inlb-dependent entry requires localized polymerization of the host actin cytoskeleton. the signal transduction pathways that act downstream of met to regulate actin filament assembly or other processes during li ... | 2017 | 28461391 |
| thermal inactivation kinetics of surface contaminating listeria monocytogenes on vacuum-packaged agar surface and ready-to-eat sliced ham and sausage. | the aim of this work was to study thermal inactivation kinetics of listeria monocytogenes on vacuum-packaged food surfaces. the kinetics were first determined on model agar systems (bhi agar plates), mimicking cooked meat products, which have the same characteristics (ph, sodium chloride (nacl) or sodium lactate (nal) content and thickness) as the cooked meat products. then, in order to validate how well the thermal inactivation on the model agar system simulated inactivation on real products, i ... | 2016 | 28460987 |
| influence of processing parameters and stress adaptation on the inactivation of listeria monocytogenes by non-thermal atmospheric plasma (ntap). | this study evaluated the effectiveness of non-thermal atmospheric plasma (ntap) treatments against listeria. firstly, the impact of gas composition and flow rate on l. monocytogenes and l. innocua (used as a surrogate) inactivation by ntap was monitored. secondly, the influence of stress adaptation (growth under suboptimal conditions, using a wide range of temperatures and media acidified up to ph5.5 with citric, lactic, malic or hydrochloric acid, or short-term exposure to acid, cold or thermal ... | 2016 | 28460960 |
| genetic and environmental factors influence listeria monocytogenes nisin resistance. | listeria monocytogenes nisin resistance increases when first exposed to nacl and other stresses, such as low ph. in addition to environmental stressors, specific genomic elements can confer nisin resistance, such as the stress survival islet (ssi-1). as ssi-1 is variably present among l. monocytogenes strains, we wanted to determine if ssi-1 was associated with salt-induced nisin resistance. | 2017 | 28452154 |
| insights into clpxp proteolysis: heterooligomerization and partial deactivation enhance chaperone affinity and substrate turnover in listeria monocytogenes. | caseinolytic proteases (clpp) are important for recognition and controlled degradation of damaged proteins. while the majority of bacterial organisms utilize only a single clpp, listeria monocytogenes expresses two isoforms (lmclpp1 and lmclpp2). lmclpps assemble into either a lmclpp2 homocomplex or a lmclpp1/2 heterooligomeric complex. the heterocomplex in association with the chaperone clpx, exhibits a boost in proteolytic activity for unknown reasons. here, we use a combined chemical and bioc ... | 2017 | 28451288 |
| structural basis of crispr-spycas9 inhibition by an anti-crispr protein. | crispr-cas9 systems are bacterial adaptive immune systems that defend against infection by phages. through the rna-guided endonuclease activity of cas9 they degrade double-stranded dna with a protospacer adjacent motif (pam) and sequences complementary to the guide rna. recently, two anti-crispr proteins (acriia2 and acriia4 from listeria monocytogenes prophages) were identified, both of which inhibit streptococcus pyogenes cas9 (spycas9) and l. monocytogenes cas9 activity in bacteria and human ... | 2017 | 28448066 |
| prevalence, antimicrobial susceptibility and multiplex pcr-serotyping of listeria monocytogenes isolated from humans, foods and livestock in iran. | listeria monocytogenes is a foodborne pathogen causing listeriosis, which potentially affects all individuals, especially pregnant women and immunocompromised persons. the present study investigated the prevalence, antimicrobial susceptibility and serotypes distribution of the isolated l. monocytogenes from iran. twenty two (4.97%) of 442 human, food and livestock samples were found to be positive for l. monocytogenes. l. monocytogenes was identified in 8.8% of 125 human samples, 2.99% of 267 fo ... | 2017 | 28445701 |
| survey for listeria monocytogenes in and on ready-to-eat foods from retail establishments in the united states (2010 through 2013): assessing potential changes of pathogen prevalence and levels in a decade. | a multiyear interagency listeria monocytogenes market basket survey was undertaken for selected refrigerated ready-to-eat foods purchased at retail in four foodnet sites in the united states. food samples from 16 food categories in six broad groups (seafood, produce, dairy, meat, eggs, and combination foods) were collected weekly at large national chain supermarkets and independent grocery stores in california, maryland, connecticut, and georgia for 100 weeks between december 2010 and march 2013 ... | 2017 | 28437165 |
| analysis of the listeria monocytogenes population structure among isolates from 1931 to 2015 in australia. | listeriosis remains among the most important bacterial illnesses, with a high associated mortality rate. efforts to control listeriosis require detailed knowledge of the epidemiology of the disease itself, and its etiological bacterium, listeria monocytogenes. in this study we provide an in-depth analysis of the epidemiology of 224 l. monocytogenes isolates from australian clinical and non-clinical sources. non-human sources included meat, dairy, seafood, fruit, and vegetables, along with animal ... | 2017 | 28428781 |
| draft genome sequences of three listeria monocytogenes isolates from foods in china. | listeria monocytogenes is a foodborne pathogen of global concern because of the high mortality rate among patients. the draft genome sequences of three l. monocytogenes strains isolated from foods are reported here. the availability of these genomes should provide useful information on the genomic diversity of l. monocytogenes isolated from foods in china. | 2017 | 28428307 |
| unique case report of a chromomycosis and listeria in soft tissue and cerebellar abscesses after kidney transplantation. | chromomycosis is a rare mycotic infection encountered in tropical and subtropical regions. the disease presents as a slowly-evolving nodule that can become infected with bacteria. here, we describe a unique association of abscesses caused by a chromomycosis and listeria monocytogenes in a kidney transplant recipient, and didactically expose how the appropriate diagnosis was reached. | 2017 | 28427354 |
| a comparative study of natural antimicrobial delivery systems for microbial safety and quality of fresh-cut lettuce. | nanoencapsulation can provide a means to effectively deliver antimicrobial compounds and enhance the safety of fresh produce. however, to date there are no studies which directly compares how different nanoencapsulation systems affect fresh produce safety and quality. this study compared the effects on quality and safety of fresh-cut lettuce treated with free and nanoencapsulated natural antimicrobial, cinnamon bark extract (cbe). a challenge study compared antimicrobial efficacy of 3 different ... | 2017 | 28425569 |
| listeria monocytogenes serotype 4b strains replicate in monocytes/macrophages more than the other serotypes. | we analyzed the pathogenicity of various serotypes of listeria monocytogenes using a balb/c mouse intravenous injection model. the survival rates of mice inoculated with strains ns1/2b (serotype 1/2b), ns3b (serotype 3b) and ns 4b (serotype 4b) were 60, 63.6 and 63.6%, respectively. although the survival rates were similar, the bacterial growth in the liver of ns3b-infected mice was 144.5-fold higher than that in the liver of ns4b-infected mice. histopathological analyses suggest that the ns4b s ... | 2017 | 28420823 |
| listeria monocytogenes meningitis in the netherlands, 1985-2014: a nationwide surveillance study. | listeria monocytogenes can cause sepsis and meningitis. we report national surveillance data on l. monocytogenes meningitis in the netherlands, describing incidence changes, genetic epidemiology and fatality rate. | 2017 | 28419853 |
| host pore-forming protein complex neutralizes the acidification of endocytic organelles to counteract intracellular pathogens. | many intracellular pathogens invade cells via endocytic organelles and have adapted to the drop in ph along the endocytic pathway. however, the strategy by which the host cell counteracts this pathogen adaptation remains unclear. βγ-cat is an aerolysin-like pore-forming protein and trefoil factor complex in the frog bombina maxima. we report here that βγ-cat, as a host-secreted factor with an intrinsic channel-forming property, is the first example of a molecule that actively neutralizes the aci ... | 2017 | 28419297 |
| comparative diagnostic efficacy of recombinant llo and pi-plc-based elisas for detection of listeriosis in animals. | the present study for the first time evaluates the serodiagnostic efficacy of two recombinant antigens namely, listeriolysin o (rllo) and phosphatidyl-inositol phospholipase c (rpi-plc). indirect elisa with the above recombinant antigens was used on samples collected from bovines (n=106), goats (n=138) and pigs (n=92) having either a history of abortion, emaciation and/or apparently healthy animals. isolation of listeria was attempted from the blood samples using usda-fsis method. on screening o ... | 2017 | 28411150 |
| screening of the two-component-system histidine kinases of listeria monocytogenes egd-e. lias is needed for growth under heat, acid, alkali, osmotic, ethanol and oxidative stresses. | to study the role of each two-component system (tcs) histidine kinase (hk) in stress tolerance of listeria monocytogenes egd-e, we monitored the growth of individual hk deletion mutant strains under heat (42.5 °c), acid (ph 5.6), alkali (ph 9.4), osmotic (6% nacl), ethanol (3.5 vol%), and oxidative (5 mm h2o2) stresses. the growth of δlias (δlmo1021) strain was impaired under each stress, with the most notable decrease under heat and osmotic stresses. the δvirs (δlmo1741) strain showed nearly co ... | 2017 | 28400017 |
| metabolic genetic screens reveal multidimensional regulation of virulence gene expression in listeria monocytogenes and an aminopeptidase that is critical for prfa protein activation. | listeria monocytogenes is an environmental saprophyte and intracellular bacterial pathogen. upon invading mammalian cells, the bacterium senses abrupt changes in its metabolic environment, which are rapidly transduced to regulation of virulence gene expression. to explore the relationship between l. monocytogenes metabolism and virulence, we monitored virulence gene expression dynamics across a library of genetic mutants grown under two metabolic conditions known to activate the virulent state: ... | 2017 | 28396325 |
| listeria monocytogenes meningitis complicating rotavirus gastroenteritis in an immunocompetent child. | listeria monocytogenes only occasionally causes bacterial meningitis in immunocompetent children. we report a case of l. monocytogenes meningitis associated with rotavirus gastroenteritis. the patient was a previously healthy 20-month-old girl who was admitted because of sustained fever and lethargy after suffering from gastroenteritis for 6 days. the patient's peripheral white blood cell count was 18,600/µl and the c-reactive protein level was 2.44 mg/dl. a stool sample tested positive for rota ... | 2017 | 28392538 |
| artisanal sonoran cheese (cocido cheese): an exploration of its production process, chemical composition and microbiological quality. | the objective of this study was to explore and document the production process of artisanal cocido cheese and to determine its chemical composition and microbiological quality, considering samples from six dairies and four retailers. | 2017 | 28295334 |
| unusual case of spondylodiscitis due to listeria monocytogenes. | | 2016 | 28529845 |
| relating physicochemical and microbiological safety indicators during processing of linguiça, a portuguese traditional dry-fermented sausage. | linguiça is a portuguese traditional fermented sausage whose microbiological quality and safety can be highly variable. in order to elucidate risk factors and the particularities of the manufacturing technology that explain the between-batch variability in total viable counts (tvc), enterobacteriaceae, staphylococcus aureus and listeria monocytogenes in the product; microbiological and physicochemical characterisation of linguiça at five stages of production (i.e., raw pork meat, mixed with ingr ... | 2015 | 28433317 |
| the challenge of challenge testing to monitor listeria monocytogenes growth on ready-to-eat foods in europe by following the european commission (2014) technical guidance document. | european regulation (ec) no. 2073/2005 lays down the microbiological criteria for certain microorganisms in foods and the implementing rules to be complied with by food business operators (fbos) in europe when implementing general and specific hygiene measures. in relation to listeria monocytogenes, this regulation covers primarily ready-to-eat (rte) food products, and requires different microbiological criteria depending on the ability of the food product to support growth of l. monocytogenes. ... | 2015 | 28454952 |
| modeling the protective effect of aw and fat content on the high pressure resistance of listeria monocytogenes in dry-cured ham. | high pressure processing (hpp) is a promising food preservation technology as an alternative to thermal processing for microbial inactivation. the technological parameters, the type of microorganism, and the food composition can greatly affect the microbicidal potential of hpp against spoilage and pathogenic microorganisms. presently, the number of available models quantifying the influence of food characteristics on the pathogen inactivation is scarce. the aim of this study was to model the ina ... | 2015 | 28454947 |