| matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) can precisely discriminate the lineages of listeria monocytogenes and species of listeria. | the genetic lineages of listeria monocytogenes and other species of the genus listeria are correlated with pathogenesis in humans. although matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) has become a prevailing tool for rapid and reliable microbial identification, the precise discrimination of listeria species and lineages remains a crucial issue in clinical settings and for food safety. in this study, we constructed an accurate and reliable ms databa ... | 2016 | 27442502 |
| thusin, a novel two-component lantibiotic with potent antimicrobial activity against several gram-positive pathogens. | due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant ... | 2016 | 27486447 |
| sublethal concentrations of antibiotics cause shift to anaerobic metabolism in listeria monocytogenes and induce phenotypes linked to antibiotic tolerance. | the human pathogenic bacterium listeria monocytogenes is exposed to antibiotics both during clinical treatment and in its saprophytic lifestyle. as one of the keys to successful treatment is continued antibiotic sensitivity, the purpose of this study was to determine if exposure to sublethal antibiotic concentrations would affect the bacterial physiology and induce antibiotic tolerance. transcriptomic analyses demonstrated that each of the four antibiotics tested caused an antibiotic-specific ge ... | 2016 | 27462313 |
| different transcriptional responses from slow and fast growth rate strains of listeria monocytogenes adapted to low temperature. | listeria monocytogenes has become one of the principal foodborne pathogens worldwide. the capacity of this bacterium to grow at low temperatures has opened an interesting field of study in terms of the identification and classification of new strains of l. monocytogenes with different growth capacities at low temperatures. we determined the growth rate at 8°c of 110 strains of l. monocytogenes isolated from different food matrices. we identified a group of slow and fast strains according to thei ... | 2016 | 26973610 |
| 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 ... | 2014 | 25188450 |
| potential bio-control agent from rhodomyrtus tomentosa against listeria monocytogenes. | listeria monocytogenes is an important foodborne pathogen implicated in many outbreaks of listeriosis. this study aimed at screening for the potential use of rhodomyrtus tomentosa ethanolic leaf extract as a bio-control agent against l. monocytogenes. twenty-two l. monocytogenes isolates were checked with 16 commercial antibiotics and isolates displayed resistance to 10 antibiotics. all the tested isolates were sensitive to the extract with inhibition zones ranging from 14 to 16 mm. minimum inhi ... | 2015 | 26371033 |
| evaluation of the performance of quantitative detection of the listeria monocytogenes prfa locus with droplet digital pcr. | fast and reliable pathogen detection is an important issue for human health. since conventional microbiological methods are rather slow, there is growing interest in detection and quantification using molecular methods. the droplet digital polymerase chain reaction (ddpcr) is a relatively new pcr method for absolute and accurate quantification without external standards. using the listeria monocytogenes specific prfa assay, we focused on the questions of whether the assay was directly transferab ... | 2016 | 27558101 |
| antagonistic effect of pseudomonas sp. cmi-1 on
foodborne pathogenic listeria monocytogenes. | bacterial isolates derived from food or raw food materials of animal origin were screened for potential antagonistic activity against foodborne pathogenic listeria monocytogenes. using the agar spot method, ten out of the 94 tested bacteria showed antilisterial activity. all of the antagonistic isolates identified by sequence analysis as strains of the genus pseudomonas were able to inhibit the growth of all the examined listeria species including the ruminal pathogenic l. ivanovii and the oppor ... | 2015 | 27904352 |
| microrna response to listeria monocytogenes infection in epithelial cells. | micrornas represent a family of very small non-coding rnas that control several physiologic and pathologic processes, including host immune response and cancer by antagonizing a number of target mrnas. there is limited knowledge about cell expression and the regulatory role of micrornas following bacterial infections. we investigated whether infection with a gram-positive bacterium leads to altered expression of micrornas involved in the host cell response in epithelial cells. caco-2 cells were ... | 2012 | 22312311 |
| the agr communication system provides a benefit to the populations of listeria monocytogenes in soil. | in this study, we investigated whether the agr communication system of the pathogenic bacterium listeria monocytogenes was involved in adaptation and competitiveness in soil. alteration of the ability to communicate, either by deletion of the gene coding the response regulator agra (response-negative mutant) or the signal pro-peptide agrd (signal-negative mutant), did not affect population dynamics in soil that had been sterilized but survival was altered in biotic soil suggesting that the agr s ... | 2014 | 25414837 |
| a multicopy srna of listeria monocytogenes regulates expression of the virulence adhesin lapb. | the multicopy srna lhrc of the intracellular pathogen listeria monocytogenes has been shown to be induced under infection-relevant conditions, but its physiological role and mechanism of action is not understood. in an attempt to pinpoint the exact terms of lhrc expression, cell envelope stress could be defined as a specific inducer of lhrc. in this process, the two-component system lisrk was shown to be indispensable for expression of all five copies of lhrc. lapb mrna, encoding a cell wall ass ... | 2014 | 25034691 |
| uv light inactivation of human and plant pathogens in unfiltered surface irrigation water. | fruit and vegetable growers continually battle plant diseases and food safety concerns. surface water is commonly used in the production of fruits and vegetables and can harbor both human- and plant-pathogenic microorganisms that can contaminate crops when used for irrigation or other agricultural purposes. treatment methods for surface water are currently limited, and there is a need for suitable treatment options. a liquid-processing unit that uses uv light for the decontamination of turbid ju ... | 2014 | 24242253 |
| sumoylation at the host-pathogen interface. | many viral proteins have been shown to be sumoylated with corresponding regulatory effects on their protein function, indicating that this host cell modification process is widely exploited by viral pathogens to control viral activity. in addition to using sumoylation to regulate their own proteins, several viral pathogens have been shown to modulate overall host sumoylation levels. given the large number of cellular targets for sumo addition and the breadth of critical cellular processes that a ... | 2012 | 23795346 |
| diversity and antimicrobial properties of lactic acid bacteria isolated from rhizosphere of olive trees and desert truffles of tunisia. | a total of 119 lactic acid bacteria (lab) were isolated, by culture-dependant method, from rhizosphere samples of olive trees and desert truffles and evaluated for different biotechnological properties. using the variability of the intergenic spacer 16s-23s and 16s rrna gene sequences, the isolates were identified as the genera lactococcus, pediococcus, lactobacillus, weissella, and enterococcus. all the strains showed proteolytic activity with variable rates 42% were eps producers, while only 1 ... | 2013 | 24151598 |
| chemical defence in a millipede: evaluation and characterization of antimicrobial activity of the defensive secretion from pachyiulus hungaricus (karsch, 1881) (diplopoda, julida, julidae). | the chemical defence of the millipede pachyiulus hungaricus is reported in the present paper, in which a chemical characterization is given and antimicrobial activity is determined. in total, independently of sex, 44 compounds were identified. all compounds belong to two groups: quinones and pentyl and hexyl esters of long-chain fatty acids. the relative abundances of quinones and non-quinones were 94.7% vs. 5.3% (males) and 87.3% vs. 12.7% (females), respectively. the two dominant quinones in b ... | 2016 | 27907048 |
| 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 ... | 2014 | 25136010 |
| structural basis for glutathione-mediated activation of the virulence regulatory protein prfa in listeria. | infection by the human bacterial pathogen listeria monocytogenes is mainly controlled by the positive regulatory factor a (prfa), a member of the crp/fnr family of transcriptional activators. published data suggest that prfa requires the binding of a cofactor for full activity, and it was recently proposed that glutathione (gsh) could fulfill this function. here we report the crystal structures of prfa in complex with gsh and in complex with gsh and its cognate dna, the hly operator prfa box mot ... | 2016 | 27930316 |
| allosteric mutants show that prfa activation is dispensable for vacuole escape but required for efficient spread and listeria survival in vivo. | the transcriptional regulator prfa controls key virulence determinants of the facultative intracellular pathogen listeria monocytogenes. prfa-dependent gene expression is strongly induced within host cells. while the basis of this activation is unknown, the structural homology of prfa with the camp receptor protein (crp) and the finding of constitutively activated prfa* mutants suggests it may involve ligand-induced allostery. here, we report the identification of a solvent-accessible cavity wit ... | 2012 | 22646689 |
| characterisation of the transcriptomes of genetically diverse listeria monocytogenes exposed to hyperosmotic and low temperature conditions reveal global stress-adaptation mechanisms. | the ability of listeria monocytogenes to adapt to various food and food- processing environments has been attributed to its robustness, persistence and prevalence in the food supply chain. to improve the present understanding of molecular mechanisms involved in hyperosmotic and low-temperature stress adaptation of l. monocytogenes, we undertook transcriptomics analysis on three strains adapted to sub-lethal levels of these stress stimuli and assessed functional gene response. adaptation to hyper ... | 2013 | 24023890 |
| diversity of acid stress resistant variants of listeria monocytogenes and the potential role of ribosomal protein s21 encoded by rpsu. | the dynamic response of microorganisms to environmental conditions depends on the behavior of individual cells within the population. adverse environments can select for stable stress resistant subpopulations. in this study, we aimed to get more insight in the diversity within listeria monocytogenes lo28 populations, and the genetic basis for the increased resistance of stable resistant fractions isolated after acid exposure. phenotypic cluster analysis of 23 variants resulted in three clusters ... | 2015 | 26005439 |
| lyspgs formation in listeria monocytogenes has broad roles in maintaining membrane integrity beyond antimicrobial peptide resistance. | listeria monocytogenes is an intracellular, foodborne gastrointestinal pathogen that is primarily responsible for causing listeriosis or food poisoning in otherwise healthy individuals. infections that arise during pregnancy or within immune compromised individuals are much more serious resulting in the risk of fetal termination or fetal fatality postpartum in the former and septicemia or meningitis with a 20% fatality rate in the latter. while the roles of internalin proteins and listeriolysin- ... | 2014 | 24603093 |
| fatty acids regulate stress resistance and virulence factor production for listeria monocytogenes. | fatty acids (fas) are the major structural component of cellular membranes, which provide a physical and chemical barrier that insulates intracellular reactions from environmental fluctuations. the native composition of membrane fas establishes the topological and chemical parameters for membrane-associated functions and is therefore modulated diligently by microorganisms especially in response to environmental stresses. however, the consequences of altered fa composition during host-pathogen in ... | 2012 | 22843841 |
| membrane damage during listeria monocytogenes infection triggers a caspase-7 dependent cytoprotective response. | the cysteine protease caspase-7 has an established role in the execution of apoptotic cell death, but recent findings also suggest involvement of caspase-7 during the host response to microbial infection. caspase-7 can be cleaved by the inflammatory caspase, caspase-1, and has been implicated in processing and activation of microbial virulence factors. thus, caspase-7 function during microbial infection may be complex, and its role in infection and immunity has yet to be fully elucidated. here w ... | 2012 | 22807671 |
| optimizing the balance between host and environmental survival skills: lessons learned from listeria monocytogenes. | environmental pathogens - organisms that survive in the outside environment but maintain the capacity to cause disease in mammals - navigate the challenges of life in habitats that range from water and soil to the cytosol of host cells. the bacterium listeria monocytogenes has served for decades as a model organism for studies of host-pathogen interactions and for fundamental paradigms of cell biology. this ubiquitous saprophyte has recently become a model for understanding how an environmental ... | 2012 | 22827306 |
| phosphatidylinositol 5-phosphatase oculocerebrorenal syndrome of lowe protein (ocrl) controls actin dynamics during early steps of listeria monocytogenes infection. | listeria monocytogenes is a bacterial pathogen that induces its own entry into a broad range of mammalian cells through interaction of the bacterial surface protein inlb with the cellular receptor met, promoting an actin polymerization/depolymerization process that leads to pathogen engulfment. phosphatidylinositol bisphosphate (pi[4,5]p(2)) and trisphosphate (pi[3,4,5]p(3)) are two major phosphoinositide species that function as molecular scaffolds, recruiting cellular effectors that regulate a ... | 2012 | 22351770 |
| inflammasome-mediated inhibition of listeria monocytogenes-stimulated immunity is independent of myelomonocytic function. | activation of the nlrc4 inflammasome results in the secretion of il-1β and il-18 through caspase-1 and induction of pyroptosis. l. monocytogenes engineered to activate nlrc4 by expression of legionella pneumophilia flagellin (l. monocytogenes l.p.flaa) are less immunogenic for cd8(+) t cell responses than wt l. monocytogenes. it is also known that il-1β orchestrates recruitment of myelomonocytic cells (mmc), which have been shown to interfere with t cell-dendritic cells (dc) interactions in sple ... | 2013 | 24349458 |
| the transcription factor irf3 triggers "defensive suicide" necrosis in response to viral and bacterial pathogens. | although molecular components that execute noninflammatory apoptotic cell death are well defined, molecular pathways that trigger necrotic cell death remain poorly characterized. here, we show that in response to infection with adenovirus or listeria monocytogenes, macrophages in vivo undergo rapid proinflammatory necrotic death that is controlled by interferon-regulatory factor 3 (irf3). the transcriptional activity of irf3 is, surprisingly, not required for the induction of necrosis, and it pr ... | 2013 | 23770239 |
| acanthamoeba castellanii of the t4 genotype is a potential environmental host for enterobacter aerogenes and aeromonas hydrophila. | acanthamoeba can interact with a wide range of microorganisms such as viruses, algae, yeasts, protists and bacteria including legionella pneumophila, pseudomonas aeruginosa, vibrio cholerae, helicobacter pylori, listeria monocytogenes, mycobacterium spp., and escherichia coli. in this capacity, acanthamoeba has been suggested as a vector in the transmission of bacterial pathogens to the susceptible hosts. | 2013 | 23742105 |
| cyclic di-amp is critical for listeria monocytogenes growth, cell wall homeostasis, and establishment of infection. | listeria monocytogenes infection leads to robust induction of an innate immune signaling pathway referred to as the cytosolic surveillance pathway (csp), characterized by expression of beta interferon (ifn-β) and coregulated genes. we previously identified the ifn-β stimulatory ligand as secreted cyclic di-amp. synthesis of c-di-amp in l. monocytogenes is catalyzed by the diadenylate cyclase daca, and multidrug resistance transporters are necessary for secretion. to identify additional bacterial ... | 2013 | 23716572 |
| rig-i detects triphosphorylated rna of listeria monocytogenes during infection in non-immune cells. | the innate immune system senses pathogens by pattern recognition receptors in different cell compartments. in the endosome, bacteria are generally recognized by tlrs; facultative intracellular bacteria such as listeria, however, can escape the endosome. once in the cytosol, they become accessible to cytosolic pattern recognition receptors, which recognize components of the bacterial cell wall, metabolites or bacterial nucleic acids and initiate an immune response in the host cell. current knowle ... | 2013 | 23653683 |
| the listeria monocytogenes chia chitinase enhances virulence through suppression of host innate immunity. | environmental pathogens survive and replicate within the outside environment while maintaining the capacity to infect mammalian hosts. for some microorganisms, mammalian infection may be a relatively rare event. understanding how environmental pathogens retain their ability to cause disease may provide insight into environmental reservoirs of disease and emerging infections. listeria monocytogenes survives as a saprophyte in soil but is capable of causing serious invasive disease in susceptible ... | 2013 | 23512964 |
| the metabolic regulator cody links listeria monocytogenes metabolism to virulence by directly activating the virulence regulatory gene prfa. | metabolic adaptations are critical to the ability of bacterial pathogens to grow within host cells and are normally preceded by sensing of host-specific metabolic signals, which in turn can influence the pathogen's virulence state. previously, we reported that the intracellular bacterial pathogen listeria monocytogenes responds to low availability of branched-chain amino acids (bcaas) within mammalian cells by up-regulating both bcaa biosynthesis and virulence genes. the induction of virulence g ... | 2014 | 25430920 |
| receptor-interacting protein kinase-2 inhibition by cyld impairs antibacterial immune responses in macrophages. | upon infection with intracellular bacteria, nucleotide oligomerization domain protein 2 recognizes bacterial muramyl dipeptide and binds, subsequently, to receptor-interacting serine/threonine kinase 2 (ripk2), which activates immune responses via the nuclear factor kappa-light-chain enhancer of activated b cells (nf-κb) and extracellular signal-regulated kinase (erk) pathways. activation of ripk2 depends on its k63 ubiquitination by e3 ligases, whereas the deubiquitinating enzyme a20 counter re ... | 2015 | 26834734 |
| the legionella kinase legk2 targets the arp2/3 complex to inhibit actin nucleation on phagosomes and allow bacterial evasion of the late endocytic pathway. | legionella pneumophila, the etiological agent of legionellosis, replicates within phagocytic cells. crucial to biogenesis of the replicative vacuole is the dot/icm type 4 secretion system, which translocates a large number of effectors into the host cell cytosol. among them is legk2, a protein kinase that plays a key role in legionella infection. here, we identified the actin nucleator arp2/3 complex as a target of legk2. legk2 phosphorylates the arpc1b and arp3 subunits of the arp2/3 complex. l ... | 2015 | 25944859 |
| avoidance of autophagy mediated by plca or acta is required for listeria monocytogenes growth in macrophages. | listeria monocytogenes is a facultative intracellular pathogen that escapes from phagosomes and grows in the cytosol of infected host cells. most of the determinants that govern its intracellular life cycle are controlled by the transcription factor prfa, including the pore-forming cytolysin listeriolysin o (llo), two phospholipases c (plca and plcb), and acta. we constructed a strain that lacked prfa but expressed llo from a prfa-independent promoter, thereby allowing the bacteria to gain acces ... | 2015 | 25776746 |
| host endoplasmic reticulum copii proteins control cell-to-cell spread of the bacterial pathogen listeria monocytogenes. | listeria monocytogenes is a food-borne pathogen that uses actin-dependent motility to spread between human cells. cell-to-cell spread involves the formation by motile bacteria of plasma membrane-derived structures termed 'protrusions'. in cultured enterocytes, the secreted listeria protein inlc promotes protrusion formation by binding and inhibiting the human scaffolding protein tuba. here we demonstrate that protrusions are controlled by human copii components that direct trafficking from the e ... | 2015 | 25529574 |
| a diverse range of bacterial and eukaryotic chitinases hydrolyzes the lacnac (galβ1-4glcnac) and lacdinac (galnacβ1-4glcnac) motifs found on vertebrate and insect cells. | there is emerging evidence that chitinases have additional functions beyond degrading environmental chitin, such as involvement in innate and acquired immune responses, tissue remodeling, fibrosis, and serving as virulence factors of bacterial pathogens. we have recently shown that both the human chitotriosidase and a chitinase from salmonella enterica serovar typhimurium hydrolyze lacnac from galβ1-4glcnacβ-tetramethylrhodamine (lacnac-tmr (galβ1-4glcnacβ(ch2)8conh(ch2)2nhco-tmr)), a fluorescen ... | 2015 | 25561735 |
| septins and bacterial infection. | septins, a unique cytoskeletal component associated with cellular membranes, are increasingly recognized as having important roles in host defense against bacterial infection. a role for septins during invasion of listeria monocytogenes into host cells was first proposed in 2002. since then, work has shown that septins assemble in response to a wide variety of invasive bacterial pathogens, and septin assemblies can have different roles during the bacterial infection process. here we review the i ... | 2016 | 27891501 |
| modulation of stat-1 in human macrophages infected with different species of intracellular pathogenic bacteria. | the infection of human macrophages by pathogenic bacteria induces different signaling pathways depending on the type of cellular receptors involved in the microorganism entry and on their mechanism(s) of survival and replication in the host cell. it was reported that stat proteins play an important role in this process. in the present study, we investigate the changes in stat-1 activation (phosphorylation in p-tyr701) after uptake of two gram-positive (listeria monocytogenes and staphylococcus a ... | 2016 | 27437406 |
| spovg is a conserved rna-binding protein that regulates listeria monocytogenes lysozyme resistance, virulence, and swarming motility. | in this study, we sought to characterize the targets of the abundantlisteria monocytogenesnoncoding rna rli31, which is required forl. monocytogeneslysozyme resistance and pathogenesis. whole-genome sequencing of lysozyme-resistant suppressor strains identified loss-of-expression mutations in the promoter ofspovg, and deletion ofspovgrescued lysozyme sensitivity and attenuationin vivoof therli31mutant. spovg was demonstrated to be an rna-binding protein that interacted with rli31in vitro.the rel ... | 2016 | 27048798 |
| response to interferons and antibacterial innate immunity in the absence of tyrosine-phosphorylated stat1. | signal transducer and activator of transcription 1 (stat1) plays a pivotal role in the innate immune system by directing the transcriptional response to interferons (ifns). stat1 is activated by janus kinase (jak)-mediated phosphorylation of y701. to determine whether stat1 contributes to cellular responses without this phosphorylation event, we generated mice with y701 mutated to a phenylalanine (stat1(y701f)). we show that heterozygous mice do not exhibit a dominant-negative phenotype. homozyg ... | 2016 | 26882544 |
| brain abscess following rituximab infusion in a patient with pemphigus vulgaris. | immunocompromised patients are at increased risk for developing meningitis or, rarely, brain abscess with opportunistic organisms like listeria monocytogenes. | 2015 | 25659437 |
| a new hybrid bacteriocin, ent35-mccv, displays antimicrobial activity against pathogenic gram-positive and gram-negative bacteria. | bacteriocins and microcins are ribosomally synthesized antimicrobial peptides that are usually active against phylogenetically related bacteria. thus, bacteriocins are active against gram-positive while microcins are active against gram-negative bacteria. the narrow spectrum of action generally displayed by bacteriocins from lactic acid bacteria represents an important limitation for the application of these peptides as clinical drugs or as food biopreservatives. the present study describes the ... | 2012 | 23650575 |
| listeria monocytogenes triggers the cell surface expression of gp96 protein and interacts with its n terminus to support cellular infection. | listeria monocytogenes is an intracellular food-borne pathogen causing listeriosis in humans. this bacterium deploys an arsenal of virulence factors that act in concert to promote cellular infection. bacterial surface proteins are of primary importance in the process of host cell invasion. they interact with host cellular receptors, inducing/modulating specific cellular responses. we previously identified vip, a listeria surface protein covalently attached to the bacterial cell wall acting as a ... | 2012 | 23109341 |
| listeria monocytogenes dampens the dna damage response. | the dna damage response (ddr) is an essential signaling pathway that detects dna lesions, which constantly occur upon either endogenous or exogenous assaults, and maintains genetic integrity. an infection by an invading pathogen is one such assault, but how bacteria impact the cellular ddr is poorly documented. here, we report that infection with listeria monocytogenes induces host dna breaks. strikingly, the signature response to these breaks is only moderately activated. we uncover the role of ... | 2014 | 25340842 |
| 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 ... | 2014 | 25147601 |
| listeria monocytogenes endophthalmitis following keratoconjunctivitis. | endophthalmitis due to endogenous or exogenous bacteria is a rare infection of the eye. we report a case of endophthalmitis following listeria monocytogenes keratoconjunctivitis in a 27-year-old healthy white male presenting with hand motion visual acuity, right eye mucopurulent conjunctivitis, elevated intraocular pressure, and pigmented hypopyon 6 months post-keratectomy. the conjunctivitis was unresponsive to a 5-day course of topical tobramycin eye drops, and the patient developed keratitis ... | 2014 | 24493921 |
| listeria monocytogenes induces host dna damage and delays the host cell cycle to promote infection. | listeria monocytogenes (lm) is a human intracellular pathogen widely used to uncover the mechanisms evolved by pathogens to establish infection. however, its capacity to perturb the host cell cycle was never reported. we show that lm infection affects the host cell cycle progression, increasing its overall duration but allowing consecutive rounds of division. a complete lm infectious cycle induces a s-phase delay accompanied by a slower rate of dna synthesis and increased levels of host dna stra ... | 2014 | 24552813 |
| licheniocin 50.2 and bacteriocins from lactococcus lactis subsp. lactis biovar. diacetylactis bgbu1-4 inhibit biofilms of coagulase negative staphylococci and listeria monocytogenes clinical isolates. | coagulase negative staphylococci (cons) and listeria monocytogenes have important roles in pathogenesis of various genital tract infections and fatal foetomaternal infections, respectively. the aim of our study was to investigate the inhibitory effects of two novel bacteriocins on biofilms of cons and l. monocytogenes genital isolates. | 2016 | 27930711 |
| comparison of surface proteomes of adherence variants of listeria monocytogenes using lc-ms/ms for identification of potential surface adhesins. | the ability of listeria monocytogenes to adhere and form biofilms leads to persistence in food processing plants and food-associated listeriosis. the role of specific surface proteins as adhesins to attach listeria cells to various contact surfaces has not been well characterized to date. in prior research comparing different methods for surface protein extraction, the ghost urea method revealed cleaner protein content as verified by the least cytoplasmic protein detected in surface extracts usi ... | 2016 | 27196934 |
| antimicrobial activity of croton macrostachyus stem bark extracts against several human pathogenic bacteria. | in kenya, leaves and roots from croton macrostachyus are used as a traditional medicine for infectious diseases such as typhoid and measles, but reports on possible antimicrobial activity of stem bark do not exist. in this study, the antibacterial and antifungal effects of methanol, ethyl acetate and butanol extracts, and purified lupeol of c. macrostachyus stem bark were determined against important human gram-negative pathogens escherichia coli, salmonella typhi, klebsiella pneumoniae, and ent ... | 2016 | 27293897 |
| bacterial meningitis in hiv-infected patients: case reports and review of the literature. | meningitis is not an uncommon complication of the acquired immune deficiency syndrome. purulent meningitis is not a well recognized infection in human immunodeficiency virus (hiv) positive patients. three cases of bacterial meningitis caused by streptococcus pneumoniae, neisseria meningitidis and listeria monocytogenes are presented. these cases illustrate that common community organisms may present in hiv positive patients. an acquired b cell defect may predispose to bacterial infections respon ... | 1992 | 22529735 |
| intracerebral hemorrhages in adults with community associated bacterial meningitis in adults: should we reconsider anticoagulant therapy? | to study the incidence, clinical presentation and outcome of intracranial hemorrhagic complications in adult patients with community associated bacterial meningitis. | 2012 | 23028898 |
| listeria monocytogenes meningitis in adults: the czech republic experience. | listeria monocytogenes (lm) is currently the third most frequent pathogen of bacterial meningitis in adults. | 2013 | 24106719 |
| reassessment of the listeria monocytogenes pan-genome reveals dynamic integration hotspots and mobile genetic elements as major components of the accessory genome. | listeria monocytogenes is an important food-borne pathogen and model organism for host-pathogen interaction, thus representing an invaluable target considering research on the forces governing the evolution of such microbes. the diversity of this species has not been exhaustively explored yet, as previous efforts have focused on analyses of serotypes primarily implicated in human listeriosis. we conducted complete genome sequencing of 11 strains employing 454 gs flx technology, thereby achieving ... | 2013 | 23339658 |
| cerebrospinal fluid inflammatory markers in patients with listeria monocytogenes meningitis. | listeria monocytogenes meningitis is the third most common cause of bacterial meningitis and is associated with high rates of mortality and unfavorable outcome. | 2014 | 25960946 |
| dnase-sensitive and -resistant modes of biofilm formation by listeria monocytogenes. | listeria monocytogenes is able to form biofilms on various surfaces and this ability is thought to contribute to persistence in the environment and on contact surfaces in the food industry. extracellular dna (edna) is a component of the biofilm matrix of many bacterial species and was shown to play a role in biofilm establishment of l. monocytogenes. in the present study, the effect of dnasei treatment on biofilm formation of l. monocytogenes egd-e was investigated under static and dynamic condi ... | 2015 | 26733972 |
| culture negative listeria monocytogenes meningitis resulting in hydrocephalus and severe neurological sequelae in a previously healthy immunocompetent man with penicillin allergy. | a previously healthy 74-year-old caucasian man with penicillin allergy was admitted with evolving headache, confusion, fever, and neck stiffness. treatment for bacterial meningitis with dexamethasone and monotherapy ceftriaxone was started. the cerebrospinal fluid showed negative microscopy for bacteria, no bacterial growth, and negative polymerase chain reaction for bacterial dna. the patient developed hydrocephalus on a second ct scan of the brain on the 5th day of admission. an external ventr ... | 2015 | 26697245 |
| listeria monocytogenes meningitis in an immunosuppressed patient with autoimmune hepatitis and igg4 subclass deficiency. | a 51-year-old caucasian woman with listeria monocytogenes meningitis was treated and discharged after an uncomplicated course. her medical history included immunosuppressive treatment with prednisolone and azathioprine for autoimmune hepatitis. a diagnostic work-up after the meningitis episode revealed that she had low levels of the igg4 subclass. to our knowledge, this is the first case report describing a possible association between autoimmune hepatitis and the occurrence of listeria monocyto ... | 2015 | 26558118 |
| protein-protein interaction domains of bacillus subtilis diviva. | diviva proteins are curvature-sensitive membrane binding proteins that recruit other proteins to the poles and the division septum. they consist of a conserved n-terminal lipid binding domain fused to a less conserved c-terminal domain. diviva homologues interact with different proteins involved in cell division, chromosome segregation, genetic competence, or cell wall synthesis. it is unknown how diviva interacts with these proteins, and we used the interaction of bacillus subtilis diviva with ... | 2013 | 23264578 |
| deciphering host genotype-specific impacts on the metabolic fingerprint of listeria monocytogenes by ftir spectroscopy. | bacterial pathogens are known for their wide range of strategies to specifically adapt to host environments and infection sites. an in-depth understanding of these adaptation mechanisms is crucial for the development of effective therapeutics and new prevention measures. in this study, we assessed the suitability of fourier transform infrared (ftir) spectroscopy for monitoring metabolic adaptations of the bacterial pathogen listeria monocytogenes to specific host genotypes and for exploring the ... | 2014 | 25541972 |
| phenotypes associated with the essential diadenylate cyclase cdaa and its potential regulator cdar in the human pathogen listeria monocytogenes. | cyclic diadenylate monophosphate (c-di-amp) is a second messenger utilized by diverse bacteria. in many species, including the gram-positive human pathogen listeria monocytogenes, c-di-amp is essential for growth. here we show that the single diadenylate cyclase of l. monocytogenes, cdaa, is an integral membrane protein that interacts with its potential regulatory protein, cdar, via the transmembrane protein domain. the presence of the cdar protein is not required for the membrane localization a ... | 2016 | 26527648 |
| chitinase expression in listeria monocytogenes is positively regulated by the agr system. | the food-borne pathogen listeria monocytogenes encodes two chitinases, chia and chib, which allow the bacterium to hydrolyze chitin, the second most abundant polysaccharide in nature. intriguingly, despite the absence of chitin in human and mammalian hosts, both of the chitinases have been deemed important for infection, through a mechanism that, at least in the case of chia, involves modulation of host immune responses. in this study, we show that the expression of the two chitinases is subject ... | 2014 | 24752234 |
| a riboswitch-regulated antisense rna in listeria monocytogenes. | riboswitches are ligand-binding elements located in 5' untranslated regions of messenger rnas, which regulate expression of downstream genes. in listeria monocytogenes, a vitamin b12-binding (b12) riboswitch was identified, not upstream of a gene but downstream, and antisense to the adjacent gene, pocr, suggesting it might regulate pocr in a nonclassical manner. in salmonella enterica, pocr is a transcription factor that is activated by 1,2-propanediol, and subsequently activates expression of t ... | 2013 | 23878253 |
| detection and identification of salmonella enterica, escherichia coli, and shigella spp. via pcr-electrospray ionization mass spectrometry: isolate testing and analysis of food samples. | an assay to identify the common food-borne pathogens salmonella, escherichia coli, shigella, and listeria monocytogenes was developed in collaboration with ibis biosciences (a division of abbott molecular) for the plex-id biosensor system, a platform that uses electrospray ionization mass spectroscopy (esi-ms) to detect the base composition of short pcr amplicons. the new food-borne pathogen (fbp) plate has been experimentally designed using four gene segments for a total of eight amplicon targe ... | 2012 | 23001674 |
| prevalence and relative risk of cronobacter spp., salmonella spp., and listeria monocytogenes associated with the body surfaces and guts of individual filth flies. | although flies are important vectors of food-borne pathogens, there is little information to accurately assess the food-related health risk of the presence of individual flies, especially in urban areas. this study quantifies the prevalence and the relative risk of food-borne pathogens associated with the body surfaces and guts of individual wild flies. one hundred flies were collected from the dumpsters of 10 randomly selected urban restaurants. flies were identified using taxonomic keys before ... | 2012 | 22941079 |
| comparison of culture, conventional and real-time pcr methods for listeria monocytogenes in foods. | we compared standard culture methods as well as conventional pcr and real-time pcr for the detection of listeria monocytogenes (l. monocytogenes) in milk, cheese, fresh-cut vegetables, and raw beef that have different levels of background microflora. no statistical differences were observed in sensitivity between the two selective media in all foods. in total, real-time pcr assay exhibited statistically excellent detection sensitivity (p<0.05) and was less time consuming and laborious as compare ... | 2014 | 26761501 |
| 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 ... | 2014 | 25149449 |
| hygienic-sanitary evaluation of sushi and sashimi sold in messina and catania, italy. | sushi and sashimi are traditional japanese food, mostly consisting of raw seafood alone or in combination with rice. eating sushi and sashimi has become popular in many countries even outside japan. this food is not free from health risks such as ingestion of pathogenic bacteria or parasite. the aim of this study was to investigate on hygienic-sanitary quality of sushi and sashimi sold in the cities of messina and catania, southern italy. fifty samples (38 sushi and 12 sashimi) were analysed to ... | 2014 | 27800343 |
| isolation of cronobacter spp. (enterobacter sakazakii) from artisanal mozzarella. | cronobacter spp. (enterobacter sakazakii) is an opportunistic bacterial pathogen capable of causing disease and even fatalities in newborn infants within the first weeks of life if consumed as part of the diet. premature and immunocompromised newborn infants are at particular risk. the microorganism has been isolated from a variety of foods including contaminated infant milk formula powder and milk powder substitute. the study aimed to evaluate the level of microbiological contamination in 47 sa ... | 2014 | 27800308 |
| development of a novel selective and differential medium for the isolation of listeria monocytogenes. | a new medium (lecithin and levofloxacin [ll] medium) is described for the isolation of listeria monocytogenes from food samples. ll medium includes lecithin from soybeans for the detection of phosphatidylinositol-specific phospholipase c (pi-plc) and phosphatidylcholine-specific phospholipase c (pc-plc) produced by l. monocytogenes. levofloxacin is incorporated to inhibit the growth of microorganisms other than l. monocytogenes, especially bacillus cereus, shown to possess pi-plc and pc-plc acti ... | 2014 | 24271177 |
| ingested salmonella enterica, cronobacter sakazakii, escherichia coli o157:h7, and listeria monocytogenes: transmission dynamics from adult house flies to their eggs and first filial (f1) generation adults. | the mechanical transmission of pathogenic bacteria by synanthropic filth flies is widely recognized. while many studies report the fate and the temporospatial distribution of ingested foodborne bacteria by filth flies, there is little evidence about the transmission dynamics of ingested foodborne bacteria by adult house flies (musca domestica) to their progeny. in this study, we fed parental house fly adults with food contaminated with low, medium, and high concentrations of salmonella enterica, ... | 2015 | 26228457 |
| microbiological findings in ready-to-eat and precooked food distributed in public catering halls in cagliari province, italy. | during this research 159 samples of ready-to-eat and precooked food were examined for the detection of salmonella spp., listeria monocytogenes, escherichia coli, coagulase-positive staphylococci and enterobacteriaceae, bacterial count. all samples were negative for salmonella spp. and listeria monocytogenes; although a low count of coagulase-positive staphylococci (no. 5 samples) and e. coli (no. 3) was found. we proceeded with the identification of the isolates on every sample with high, modera ... | 2014 | 27800358 |
| effect of atmospheric pressure plasma jet on the foodborne pathogens attached to commercial food containers. | bacterial biofilms are associated with numerous infections and problems in the health care and food industries. the aim of this study was to evaluate the bactericidal effect of an atmospheric pressure plasma (app) jet on escherichia coli o157:h7, listeria monocytogenes, and salmonella typhimurium biofilm formation on collagen casing (cc), polypropylene (pp) and polyethylene terephthalate (pet), which are widely used food container materials. the samples were treated separately with the app jet a ... | 2015 | 26604423 |
| highly specific fiber optic immunosensor coupled with immunomagnetic separation for detection of low levels of listeria monocytogenes and l. ivanovii. | immunomagnetic separation (ims) and immunoassays are widely used for pathogen detection. however, novel technology platforms with highly selective antibodies are essential to improve detection sensitivity, specificity and performance. in this study, monoclonal antibodies (mabs) against internalin a (inla) and p30 were generated and used on paramagnetic beads of varying diameters for concentration, as well as on fiber-optic sensor for detection. | 2012 | 23176167 |
| expanding the use of a fluorogenic method to determine activity and mode of action of bacillus thuringiensis bacteriocins against gram-positive and gram-negative bacteria. | previously we described a rapid fluorogenic method to measure the activity of five bacteriocins produced by mexican strains of bacillus thuringiensis against b. cereus 183. here we standardize this method to efficiently determine the activity of bacteriocins against both gram-positive and gram-negative bacteria. it was determined that the crucial parameter required to obtain reproducible results was the number of cells used in the assay, that is, ~4 × 10(8) cell/ml and ~7 × 10(8) cell/ml, respec ... | 2012 | 22919330 |
| functional characterization of the infection-inducible peptide edin in drosophila melanogaster. | drosophila is a well-established model organism for studying innate immunity because of its high resistance against microbial infections and lack of adaptive immunity. in addition, the immune signaling cascades found in drosophila are evolutionarily conserved. upon infection, activation of the immune signaling pathways, toll and imd, leads to the expression of multiple immune response genes, such as the antimicrobial peptides (amps). previously, we identified an uncharacterized gene edin among t ... | 2012 | 22606343 |
| the unique structure of haemophilus influenzae protein e reveals multiple binding sites for host factors. | haemophilus influenzae protein e (pe) is a multifunctional adhesin involved in direct interactions with lung epithelial cells and host proteins, including plasminogen and the extracellular matrix proteins vitronectin and laminin. we recently crystallized pe and successfully collected x-ray diffraction data at 1.8 å. here, we solved the structure of a recombinant version of pe and analyzed different functional regions. it is a dimer in solution and in the asymmetric unit of the crystals. the dime ... | 2013 | 23275089 |
| uncommon manifestations of listeria monocytogenes infection. | listeria monocytogenes causes gastroenteritis, meningitis and bacteraemia in immunocompromised, pregnant patients, the elderly as well in immunocompetent patients. focal infections with this organism are uncommon, especially in sporadic (non-outbreak) setting, require high index of suspicion and are challenging to diagnose. we present 3 cases of listeria monocytogenes presenting as focal infections to our hospitals, all of which are the first reported cases from australia. | 2014 | 25466213 |
| 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 ... | 2014 | 25084660 |
| chemical composition, antioxidant and antimicrobial activities of thymus capitata essential oil with its preservative effect against listeria monocytogenes inoculated in minced beef meat. | the chemical composition, antioxidant and antimicrobial activities, and the preservative effect of thymus capitata essential oil against listeria monocytogenes inoculated in minced beef meat were evaluated. the essential oil extracted was chemically analyzed by gas chromatography-mass spectrometry. nineteen components were identified, of which carvacrol represented (88.89%) of the oil. the antioxidant activity was assessed in vitro by using both the dpph and the abts assays. the findings showed ... | 2014 | 24719640 |
| fructose 1,6-bisphosphate aldolase, a novel immunogenic surface protein on listeria species. | listeria monocytogenes is a ubiquitous food-borne pathogen, and its presence in food or production facilities highlights the importance of surveillance. increased understanding of the surface exposed antigens on listeria would provide potential diagnostic and therapeutic targets. in the present work, using mass spectrometry and genetic cloning, we show that fructose-1,6-bisphosphate aldolase (fba) class ii in listeria species is the antigen target of the previously described mab-3f8. western and ... | 2016 | 27489951 |
| antimicrobial activity of serbian propolis evaluated by means of mic, hptlc, bioautography and chemometrics. | new information has come to light about the biological activity of propolis and the quality of natural products which requires a rapid and reliable assessment method such as high performance thin-layer chromatography (hptlc) fingerprinting. this study investigates chromatographic and chemometric approaches for determining the antimicrobial activity of propolis of serbian origin against various bacterial species. a linear multivariate calibration technique, using partial least squares, was used t ... | 2016 | 27272728 |
| development of multiple cross displacement amplification label-based gold nanoparticles lateral flow biosensor for detection of listeria monocytogenes. | listeria monocytogenes, one of most problematic foodborne pathogens, is responsible for listeriosis in both humans and animals and mainly transmitted through the food chain. in this report, we propose a simple, rapid, and nearly instrument-free molecular technique using multiple cross displacement amplification (mcda) label-based gold nanoparticles lateral flow biosensor (lfb) for specific, sensitive, and visual detection of l. monocytogenes. the mcda-lfb method was carried out at a constant tem ... | 2017 | 28138243 |
| sunlight-induced rapid and efficient biogenic synthesis of silver nanoparticles using aqueous leaf extract of ocimum sanctum linn. with enhanced antibacterial activity. | nanotechnology is now regarded as a distinct field of research in modern science and technology with multifaceted areas including biomedical applications. among the various approaches currently available for the generation of metallic nanoparticles, biogenic synthesis is of increasing demand for the purpose of green nanotechnology. among various natural sources, plant materials are the most readily available template-directing matrix offering cost-effectiveness, eco-friendliness, and easy handli ... | 2014 | 25621198 |
| no effect of wolbachia on resistance to intracellular infection by pathogenic bacteria in drosophila melanogaster. | multiple studies have shown that infection with the endosymbiotic bacterium wolbachia pipientis confers drosophila melanogaster and other insects with resistance to infection by rna viruses. studies investigating whether wolbachia infection induces the immune system or confers protection against secondary bacterial infection have not shown any effect. these studies, however, have emphasized resistance against extracellular pathogens. since wolbachia lives inside the host cell, we hypothesized th ... | 2012 | 22808174 |
| cloning, characterization and effect of tmpgrp-le gene silencing on survival of tenebrio molitor against listeria monocytogenes infection. | peptidoglycan recognition proteins (pgrps) are a family of innate immune molecules that recognize bacterial peptidoglycan. pgrp-le, a member of the pgrp family, selectively binds to diaminopimelic acid (dap)-type peptidoglycan to activate both the immune deficiency (imd) and prophenoloxidase (propo) pathways in insects. a pgrp-le-dependent induction of autophagy to control listeria monocytogenes has also been reported. we identified and partially characterized a novel pgrp-le homologue, from ten ... | 2013 | 24240808 |
| genomes of sequence type 121 listeria monocytogenes strains harbor highly conserved plasmids and prophages. | the food-borne pathogen listeria (l.) monocytogenes is often found in food production environments. thus, controlling the occurrence of l. monocytogenes in food production is a great challenge for food safety. among a great diversity of l. monocytogenes strains from food production, particularly strains belonging to sequence type (st)121 are prevalent. the molecular reasons for the abundance of st121 strains are however currently unknown. we therefore determined the genome sequences of three l. ... | 2015 | 25972859 |
| 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? | 2014 | 25108145 |
| sarm is required for neuronal injury and cytokine production in response to central nervous system viral infection. | four of the five members of the toll/il-1r domain-containing adaptor family are required for signaling downstream of tlrs, promoting innate immune responses against different pathogens. however, the role of the fifth member of this family, sterile α and toll/il-1r domain-containing 1 (sarm), is unclear. sarm is expressed primarily in the cns where it is required for axonal death. studies in caenorhabditis elegans have also shown a role for sarm in innate immunity. to clarify the role of mammalia ... | 2013 | 23749635 |
| listeria monocytogenes spreads within the brain by actin-based intra-axonal migration. | listeria monocytogenes rhombencephalitis is a severe progressive disease despite a swift intrathecal immune response. based on previous observations, we hypothesized that the disease progresses by intra-axonal spread within the central nervous system. to test this hypothesis, neuroanatomical mapping of lesions, immunofluorescence analysis, and electron microscopy were performed on brains of ruminants with naturally occurring rhombencephalitis. in addition, infection assays were performed in bovi ... | 2015 | 25824833 |
| age-associated alterations in cd8α+ dendritic cells impair cd8 t-cell expansion in response to an intracellular bacterium. | age-associated decline in immunity to infection has been documented across multiple pathogens, yet the relative contributions of the aged priming environment and of lymphocyte-intrinsic defects remain unclear. to address the impact of the aging environment on t-cell priming, adult naïve ot-i tcr transgenic cd8 t cells, specific for the h-2kb-restricted immunodominant ova(257-264) epitope, were transferred into adult or old recipient mice infected with the recombinant intracellular bacterium list ... | 2012 | 22862959 |
| cytomegalovirus generates long-lived antigen-specific nk cells with diminished bystander activation to heterologous infection. | natural killer (nk) cells play a key role in the host response to cytomegalovirus (cmv) and can mediate an enhanced response to secondary challenge with cmv. we assessed the ability of mouse cmv (mcmv)-induced memory ly49h(+) nk cells to respond to challenges with influenza, an acute viral infection localized to the lung, and listeria monocytogenes, a systemic bacterial infection. mcmv-memory nk cells did not display enhanced activation or proliferation after infection with influenza or listeria ... | 2014 | 25422494 |
| single chain mhc i trimer-based dna vaccines for protection against listeria monocytogenes infection. | to circumvent limitations of poor antigen presentation and immunogenicity of dna vaccines that target induction of cd8(+) t cell immunity, we have generated single chain mhc i trimers (mhc i scts) composed of a single polypeptide chain with a linear composition of antigenic peptide, β2-microglobulin, and heavy chain of a mhc class i molecule connected by flexible linkers. because of its pre-assembled nature, the sct presents enhanced expression and presentation of the antigenic peptide/mhc compl ... | 2012 | 22285270 |
| validation of a previously developed geospatial model that predicts the prevalence of listeria monocytogenes in new york state produce fields. | technological advancements, particularly in the field of geographic information systems (gis), have made it possible to predict the likelihood of foodborne pathogen contamination in produce production environments using geospatial models. yet, few studies have examined the validity and robustness of such models. this study was performed to test and refine the rules associated with a previously developed geospatial model that predicts the prevalence of listeria monocytogenes in produce farms in n ... | 2015 | 26590280 |
| simvastatin enhances protection against listeria monocytogenes infection in mice by counteracting listeria-induced phagosomal escape. | statins are well-known cholesterol lowering drugs targeting hmg-coa-reductase, reducing the risk of coronary disorders and hypercholesterolemia. statins are also involved in immunomodulation, which might influence the outcome of bacterial infection. hence, a possible effect of statin treatment on listeriosis was explored in mice. statin treatment prior to subsequent l. monocytogenes infection strikingly reduced bacterial burden in liver and spleen (up to 100-fold) and reduced histopathological l ... | 2013 | 24086542 |
| cd14-dependent monocyte isolation enhances phagocytosis of listeria monocytogenes by proinflammatory, gm-csf-derived macrophages. | macrophages are an important line of defence against invading pathogens. human macrophages derived by different methods were tested for their suitability as models to investigate listeria monocytogenes (lm) infection and compared to macrophage-like thp-1 cells. human primary monocytes were isolated by either positive or negative immunomagnetic selection and differentiated in the presence of granulocyte macrophage colony-stimulating factor (gm-csf) or macrophage colony-stimulating factor (m-csf) ... | 2013 | 23776701 |
| cip2a promotes t-cell activation and immune response to listeria monocytogenes infection. | the oncoprotein cancerous inhibitor of protein phosphatase 2a (cip2a) is overexpressed in most malignancies and is an obvious candidate target protein for future cancer therapies. however, the physiological importance of cip2a-mediated pp2a inhibition is largely unknown. as pp2a regulates immune responses, we investigated the role of cip2a in normal immune system development and during immune response in vivo. we show that cip2a-deficient mice (cip2ahoz) present a normal immune system developmen ... | 2016 | 27100879 |
| unexpected positive control of nfκb and mir-155 by dgkα and ζ ensures effector and memory cd8+ t cell differentiation. | signals from the t-cell receptor (tcr) and γ-chain cytokine receptors play crucial roles in initiating activation and effector/memory differentiation of cd8 t-cells. we report here that simultaneous deletion of both diacylglycerol kinase (dgk) α and ζ (dko) severely impaired expansion of cd8 effector t cells and formation of memory cd8 t-cells after listeria monocytogenes infection. moreover, ablation of both dgkα and ζ in preformed memory cd8 t-cells triggered death and impaired homeostatic pro ... | 0 | 27014906 |
| the biofilm lifestyle involves an increase in bacterial membrane saturated fatty acids. | biofilm formation on contact surfaces contributes to persistence of foodborne pathogens all along the food and feed chain. the specific physiological features of bacterial cells embedded in biofilms contribute to their high tolerance to environmental stresses, including the action of antimicrobial compounds. as membrane lipid adaptation is a vital facet of bacterial response when cells are submitted to harsh or unstable conditions, we focused here on membrane fatty acid composition of biofilm ce ... | 2016 | 27840623 |