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infectious dose of listeria monocytogenes in outbreak linked to ice cream, united states, 2015.the relationship between the number of ingested listeria monocytogenes cells in food and the likelihood of developing listeriosis is not well understood. data from an outbreak of listeriosis linked to milkshakes made from ice cream produced in 1 factory showed that contaminated products were distributed widely to the public without any reported cases, except for 4 cases of severe illness in persons who were highly susceptible. the ingestion of high doses of l. monocytogenes by these patients inf ...201627869595
immune signatures of protective spleen memory cd8 t cells.memory cd8 t lymphocyte populations are remarkably heterogeneous and differ in their ability to protect the host. in order to identify the whole range of qualities uniquely associated with protective memory cells we compared the gene expression signatures of two qualities of memory cd8 t cells sharing the same antigenic-specificity: protective (influenza-induced, flu-tm) and non-protective (peptide-induced, tim) spleen memory cd8 t cells. although flu-tm and tim express classical phenotypic memo ...201627883012
closing the brief case: neonatal meningitis caused by listeria monocytogenes diagnosed by multiplex molecular panel. 201627881637
the brief case: neonatal meningitis caused by listeria monocytogenes diagnosed by multiplex molecular panel. 201627881634
how can patients and their physicians contribute to an outbreak investigation? experiences from a nationwide listeriosis outbreak in switzerland.gathering patient information to contain an outbreak of listeria monocytogenes is difficult because of the patients' severe illness or death. extending the range of interviewees to acquire epidemiological data can thus be important to maximise information.201627878798
proliferation of listeria monocytogenes l-form cells by formation of internal and external vesicles.l-forms are cell wall-deficient bacteria that divide through unusual mechanisms, involving dynamic perturbations of the cellular shape and generation of vesicles, independently of the cell-division protein ftsz. here we describe ftsz-independent mechanisms, involving internal and external vesicles, by which listeria monocytogenes l-forms proliferate. using micromanipulation of single cells and vesicles, we show that small vesicles are formed by invagination within larger intracellular vesicles, ...201627876798
1926-2016: 90 years of listeriology.isopol - for "international symposium on problems of listeria and listeriosis" - meetings gather every three years since 1957 participants from all over the world and allow exchange and update on a wide array of topics concerning listeria and listeriosis, ranging from epidemiology, diagnostic and typing methods, to genomics, post-genomics, fundamental microbiology, cell biology and pathogenesis. the xixth isopol meeting took place in paris from june 14th to 17th, 2016 at institut pasteur. we pro ...201627876526
experimental infection with listeria monocytogenes as a model for studying host interferon-γ responses.l. monocytogenes is a gram-positive bacterium that is a cause of food borne disease in humans. experimental infection of mice with this pathogen has been highly informative on the role of innate and adaptive immune cells and specific cytokines in host immunity against intracellular pathogens. production of ifn-γ by innate cells during sublethal infection with l. monocytogenes is important for activating macrophages and early control of the pathogen(1-3). in addition, ifn-γ production by adaptive ...201627911410
the majority of genotypes of the virulence gene inla are intact among natural watershed isolates of listeria monocytogenes from the central california coast.internalin a is an essential virulence gene involved in the uptake of the foodborne pathogen listeria monocytogenes into host cells. it is intact in clinical strains and often truncated due to premature stop codons (pmscs) in isolates from processed foods and processing facilities. less information is known about environmental isolates. we sequenced the inla alleles and did multi locus variable number tandem repeat analysis (mlva) on 112 l. monocytogenes isolates from a 3-year period from natura ...201627907153
assay for listeria monocytogenes cells in whole blood using isotachophoresis and recombinase polymerase amplification.we present a new approach which enables lysis, extraction, and detection of inactivated listeria monocytogenes cells from blood using isotachophoresis (itp) and recombinase polymerase amplification (rpa). we use an itp-compatible alkaline and proteinase k approach for rapid and effective lysis. we then perform itp purification to separate bacterial dna from whole blood contaminants using a microfluidic device that processes 25 μl sample volume. lysis, mixing, dispensing, and on-chip itp purifica ...201627904893
inflammation-induced cd69(+) kupffer cell feedback inhibits t cell proliferation via membrane-bound tgf-β1.kupffer cells, tissue-resident macrophage lineage cell, are enriched in vertebrate liver. the mouse f4/80(+) kupffer cells have been subclassified into two subpopulations according to their phenotype and function: cd68(+) subpopulation with potent reactive oxygen species (ros) production and phagocytic capacities, and cd11b(+) subpopulation with a potent capacity to produce t helper 1 cytokines. in addition, cd11b(+) kupffer cells/macrophages may be migrated from the bone marrow or spleen, espec ...201627933593
the role of stress and stress adaptations in determining the fate of the bacterial pathogen listeria monocytogenes in the food chain.the foodborne pathogen listeria monocytogenes is a highly adaptable organism that can persist in a wide range of environmental and food-related niches. the consumption of contaminated ready-to-eat foods can cause infections, termed listeriosis, in vulnerable humans, particularly those with weakened immune systems. although these infections are comparatively rare they are associated with high mortality rates and therefore this pathogen has a significant impact on food safety. l. monocytogenes can ...201627933042
draft genome sequences of two historical listeria monocytogenes strains from human listeriosis cases in 1933.we report here the draft genome sequences of two listeria monocytogenes strains from some of the earliest reported cases of human listeriosis in north america. the strains were isolated in 1933 from patients in massachusetts and connecticut, usa, and belong to the widely disseminated hypervirulent clonal complex 1 (cc1) and cc2.201627932656
brain abscess due to listeria monocytogenes after hellp syndrome in a patient with antiphospholipid syndrome.to illustrate an unusual case of listeria cerebral abscess.201627927881
innate immunity based cancer immunotherapy: b16-f10 murine melanoma model.using killed microorganisms or their parts to stimulate immunity for cancer treatment dates back to the end of 19(th) century. since then, it undergone considerable development. our novel approach binds ligands to the tumor cell surface, which stimulates tumor phagocytosis. the therapeutic effect is further amplified by simultaneous application of agonists of toll-like receptors. we searched for ligands that induce both a strong therapeutic effect and are safe for humans.201627927165
involvement of il-17a-producing tcr γδ t cells in late protective immunity against pulmonary mycobacterium tuberculosis infection.interleukin (il)-17a is a cytokine originally reported to induce neutrophil-mediated inflammation and anti-microbial activity. the cd4(+) t cells, which produce il-17a, have been well characterized as th17 cells. on the other hand, il-17a-producing tcr γδ(+) t cells have been reported to participate in the immune response at an early stage of infection with listeria monocytogenes and mycobacterium bovis in mice. however, the involvement of il-17a in protective immunity was not clearly demonstrat ...201627980775
prevalence and antibiotic susceptibility profiles of listeria monocytogenes contamination of chicken flocks and meat in oyo state, south-western nigeria: public health implications.food contamination with listeria monocytogenes is on the increase posing threats to public health with growing trends in food products recalls due to suspected listeria contamination.201627980380
successful treatment of refractory listeria meningitis and bacteremia with trimethoprim-sulfamethoxazole in an immunocompetent child.listeria monocytogenes is an important cause of life-threatening bacteremia and meningoencephalitis in neonates, pregnant women, the elderly, and immunocompromised individuals. however, it is an uncommon cause of illness in immunocompetent children beyond the neonatal period. ampicillin with or without an aminoglycoside remains the best treatment for listeriosis. here, we report a rare case of listeria meningitis and bacteremia in a 7-month-old immunocompetent girl, which was refractory to ampic ...201627976567
biomarker tools to design clinical vaccines determined from a study of annual listeriosis incidence in northern spain.two regions of northern spain, gipuzkoa, and cantabria present high annual incidence of listeriosis (1.86 and 1.71 cases per 100,000 inhabitants, respectively). we report that the high annual incidences are a consequence of infection with highly virulent listeria monocytogenes isolates linked to fatal outcomes in elderly patients with cancer. in addition, listeriosis patients with cancer present low il-17a/il-6 ratios and significantly reduced levels of anti-gapdh1-22 antibodies, identified as t ...201627965668
a bioengineered nisin derivative, m21a, in combination with food grade additives eradicates biofilms of listeria monocytogenes.the burden of foodborne disease has large economic and social consequences worldwide. despite strict regulations, a number of pathogens persist within the food environment, which is greatly contributed to by a build-up of resistance mechanisms and also through the formation of biofilms. biofilms have been shown to be highly resistant to a number of antimicrobials and can be extremely difficult to remove once they are established. in parallel, the growing concern of consumers regarding the use of ...201627965658
comparative genomics analyses revealed two virulent listeria monocytogenes strains isolated from ready-to-eat food.listeria monocytogenes is an important foodborne pathogen that causes considerable morbidity in humans with high mortality rates. in this study, we have sequenced the genomes and performed comparative genomics analyses on two strains, lm115 and lm41, isolated from ready-to-eat food in malaysia.201627999619
an evaluation of alternatives to nitrites and sulfites to inhibit the growth of salmonella enterica and listeria monocytogenes in meat products.in recent years, the use of nitrites and sulfites as food preservatives has been a cause for concern due to the health problems that these additives can cause in humans. natural products have been studied as an alternative, but most of them have hardly been applied in the food industry for technological and economic reasons. in this sense, organic salts such as sodium acetate are a good alternative due to their affordability. thus, this study evaluated the capacity of sodium nitrite, sodium sulf ...201628231169
behavior of salmonella and listeria monocytogenes in raw yellowfin tuna during cold storage.behavior of salmonella and listeria monocytogenes in raw yellowfin tuna during refrigeration and frozen storage were studied. growth of salmonella was inhibited in tuna during refrigerated storage, while l. monocytogenes was able to multiply significantly during refrigerated storage. populations of salmonella in tuna were reduced by 1 to 2 log after 12 days of storage at 5-7 °c, regardless levels of contamination. however, populations of l. monocytogenes scott a, m0507, and sfl0404 in inoculated ...201628231111
passive immunization with anti-acta and anti-listeriolysin o antibodies protects against listeria monocytogenes infection in mice.listeria monocytogenes is an intracellular pathogen that causes listeriosis. due to its intracellular niche, l. monocytogenes has evolved to limit immune recognition and response to infection. antibodies that are slightly induced by listerial infection are completely unable to protect re-infection of l. monocytogenes. thus, a role of antibody on the protective effect against l. monocytogenes infection has been neglected for a long time. in the present study, we reported that passive immunization ...201628004800
a20 curtails primary but augments secondary cd8(+) t cell responses in intracellular bacterial infection.the ubiquitin-modifying enzyme a20, an important negative feedback regulator of nf-κb, impairs the expansion of tumor-specific cd8(+) t cells but augments the proliferation of autoimmune cd4(+) t cells. to study the t cell-specific function of a20 in bacterial infection, we infected t cell-specific a20 knockout (cd4-cre a20(fl/fl)) and control mice with listeria monocytogenes. a20-deficient pathogen-specific cd8(+) t cells expanded stronger resulting in improved pathogen control at day 7 p.i. im ...201628004776
application of a puffer fish skin gelatin film containing moringa oleifera lam. leaf extract to the packaging of gouda cheese.this study aims to develop a puffer fish skin gelatin (psg) film that contains moringa oleifera lam. leaf extract (me) as a new biodegradable film. with the increase in me concentration, the tensile strength and elongation at break of the psg film increased, whereas the oxygen permeability and water vapor permeability decreased. in addition, the psg film with me exhibited antimicrobial activity against listeria monocytogenes and antioxidant activity. to apply the me-containing psg film to food p ...201628035143
semi-industrial microwave treatments positively affect the quality of orange-colored smoothies.thermal processing extends the shelf life of fruit and vegetables products by inactivating microorganisms and enzymes. the effect of a pasteurization (p) treatment, 90 ± 2 °c for 35 s, provided by continuous semi-industrial microwave (mw) under different conditions (high power/short time and low power/long time) or conventional pasteurization (cp) on orange-colored smoothies and their changes throughout 45 days of storage at 5 °c were investigated. results indicated that vitamin c and antioxidan ...201628017984
[spontaneous bacterial peritonitis with listeria monocytogenes leading to a cirrhosis discovery]. 201628017475
evaluation of the antibacterial activity of bergamot essential oils on different listeria monocytogenes strains.essential oils are aromatic and volatile substances extracted from plants and characterized by antimicrobial activity. the aim of the present study was to evaluate the antibacterial activity (agar disc-diffusion method) of seven different bergamot essential oils (beos) on eight listeria monocytogenes strains. minimal inhibitory concentration (mic) of most efficient beos was estimated. extremely variable results for agar disc-diffusion method for l. monocytogenes strains were reported. one of the ...201628058251
listeria monocytogenes isolates carrying virulence-attenuating mutations in internalin a are commonly isolated from ready-to-eat food processing plant and retail environments.listeria monocytogenes is a human foodborne pathogen that may cause an invasive disease known as listeriosis in susceptible individuals. internalin a (inla; encoded by inla) is a virulence factor that facilitates crossing of host cell barriers by l. monocytogenes . at least 19 single nucleotide polymorphisms (snps) in inla that result in a premature stop codon (pmsc) have been described worldwide. snps leading to a pmsc in inla have been shown to be causally associated with attenuated virulence. ...201628221857
fate of pathogenic bacteria associated with production of pickled sausage by using a cold fill process.preservation by pickling has been used for many years to extend the shelf life of various types of food products. by storing meat products in a brine solution containing an organic acid, salt, spices, as well as other preservatives, the ph of the product is reduced, thus increasing the safety and shelf life of the product. pickling may involve the use of heated brines to further add to the safety of the food product. when precooked, ready-to-eat (rte) sausages are pickled with a heated brine sol ...201628221846
environmental occurrence and antibiotic susceptibility profile of listeria monocytogenes at a slaughterhouse raw processing plant in romania.this survey was conducted to investigate the occurrence and antimicrobial susceptibility of listeria monocytogenes isolates in the environment of a pig slaughterhouse raw processing plant complex in western romania. a total of 97 environmental samples from food contact (n = 60) and nonfood contact (n = 37) surfaces were examined with standard methods. the susceptibility of the isolates to 17 antimicrobial agents was determined with the vitek 2 automated system. overall, 25 (25.8%) samples were p ...201628221837
comparative genomic analysis of two serotype 1/2b listeria monocytogenes isolates from analogous environmental niches demonstrates the influence of hypervariable hotspots in defining pathogenesis.the vast majority of clinical human listeriosis cases are caused by serotype 1/2a, 1/2b, 1/2c, and 4b isolates of listeria monocytogenes. the ability of l. monocytogenes to establish a systemic listeriosis infection within a host organism relies on a combination of genes that are involved in cell recognition, internalization, evasion of host defenses, and in vitro survival and growth. recently, whole genome sequencing and comparative genomic analysis have proven to be powerful tools for the iden ...201628066772
comparative genomics of the listeria monocytogenes st204 subgroup.the st204 subgroup of listeria monocytogenes is among the most frequently isolated in australia from a range of environmental niches. in this study we provide a comparative genomics analysis of food and food environment isolates from geographically diverse sources. analysis of the st204 genomes showed a highly conserved core genome with the majority of variation seen in mobile genetic elements such as plasmids, transposons and phage insertions. most strains (13/15) harbored plasmids, which altho ...201628066377
prevalence and genetic characteristics of meatborne listeria monocytogenes isolates from livestock farms in korea.this study aimed to evaluate the prevalence of listeria monocytogenes on livestock farms in korea and determine their serotypes and genetic correlations. twenty-five livestock farms in korea (central: 15, south west: 7, south east: 3) were visited 2-3 times, and 2,018 samples (feces: 677, soil: 680, silage: 647, sludge: 14) were collected. samples were enriched in leb (listeria enrichment broth) and fraser broth media, and then plated on palcam agar. the isolates were identified by pcr and 16s r ...201628115889
use of rhodomyrtus tomentosa ethanolic leaf extract for the bio-control of listeria monocytogenes post-cooking contamination in cooked chicken meat.controlling foodborne pathogen in ready-to-eat food is important in food safety. the present study accessed the potential use of rhodomyrtus tomentosa ethanolic leaf extract as a bio-control agent against listeria monocytogenes in cooked chicken meat model system. the antilisterial activity of the plant extract was better under microwave condition and enhanced as storage temperature increased from 4 to 37 °c. the extract could reduce l. monocytogenes numbers at low (10(4) cfu/g) and high (10(6)  ...201628115764
development and validation of pathogen environmental monitoring programs for small cheese processing facilities.pathogen environmental monitoring programs (emps) are essential for food processing facilities of all sizes that produce ready-to-eat food products exposed to the processing environment. we developed, implemented, and evaluated emps targeting listeria spp. and salmonella in nine small cheese processing facilities, including seven farmstead facilities. individual emps with monthly sample collection protocols were designed specifically for each facility. salmonella was detected in only one facilit ...201628221969
synergistic antilisterial effects of mixtures of lysozyme and organic acids.we investigated the synergistic effects of lysozyme combined with organic acids to inhibit the growth of listeria monocytogenes . the antilisterial effects of the combination of lysozyme and acetic acid, citric acid, lactic acid, malic acid, or succinic acid were evaluated using the checkerboard method and time-kill assay. the mic was 25,000 mg/liter for lysozyme, 625 mg/liter for acetic acid, and 1,250 mg/liter for the other acids. the mbc was 10,000 mg/liter for all of the tested organic acids ...201628221961
effect of power levels on inactivation of escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes in tomato paste using 915-megahertz microwave and ohmic heating.the effect of power levels on inactivation of escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes in tomato paste was investigated using 915-mhz microwave heating (mw) and ohmic heating (oh). heating uniformity, pathogen inactivation, and quality aspects were determined with 1.8-, 2.1-, 2.4-, and 3.0-kw mw and corresponding oh. ginafit was used to analyze pathogen inactivation. the heating uniformity of mw-treated samples was inferior to that of oh-treated samples at low ...201628221946
effect of temperature and nutrient concentration on survival of foodborne pathogens in deciduous fruit processing environments for effective hygiene management.temperature and good sanitation practices are important factors for controlling growth of microorganisms. fresh produce is stored at various temperatures to ensure quality and to prolong shelf life. when foodborne pathogens survive and grow on fresh produce at storage temperatures, then additional control strategies are needed to inactivate these pathogens. the aim of this study was to determine how temperatures associated with deciduous fruit processing and storage facilities (0.5, 4, and 21°c) ...201628221909
prevalence and level of listeria monocytogenes in ice cream linked to a listeriosis outbreak in the united states.a most-probable-number (mpn) method was used to enumerate listeria monocytogenes in 2,320 commercial ice cream scoops manufactured on a production line that was implicated in a 2015 listeriosis outbreak in the united states. the analyzed samples were collected from seven lots produced in november 2014, december 2014, january 2015, and march 2015. l. monocytogenes was detected in 99% (2,307 of 2,320) of the tested samples (lower limit of detection, 0.03 mpn/g), 92% of which were contaminated at < ...201628221903
prevalence and persistence of listeria monocytogenes in ready-to-eat tilapia sashimi processing plants.a 2-year study was performed at two ready-to-eat tilapia sashimi processing plants (a and b) to identify possible routes of contamination with listeria monocytogenes during processing. samples were collected from the aquaculture environments, transportation tanks, processing plants, and final products. seventy-nine l. monocytogenes isolates were found in the processing environments and final products; 3.96% (50 of 1,264 samples) and 3.86% (29 of 752 samples) of the samples from plants a and b, r ...201628221901
ngmaster:in silico multi-antigen sequence typing for neisseria gonorrhoeae.whole-genome sequencing (wgs) provides the highest resolution analysis for comparison of bacterial isolates in public health microbiology. however, although increasingly being used routinely for some pathogens such as listeria monocytogenes and salmonella enterica, the use of wgs is still limited for other organisms, such as neisseria gonorrhoeae. multi-antigen sequence typing (ng-mast) is the most widely performed typing method for epidemiological surveillance of gonorrhoea. here, we present ng ...201628348871
listeria ivanovii infection in mice: restricted to the liver and lung with limited replication in the spleen.listeria monocytogenes (lm) vectors have shown much promise in delivery of viral and tumor antigens for the development of vaccines. l. ivanovii (li) is a closely related bacterium with a similar intracellular life cycle that may offer advantages over lm because it is not a human pathogen, but can infect other animal species. recent studies show that recombinant li expressing mycobacterium tuberculosis antigens is effective in inducing protective immunity in mouse models, demonstrating the poten ...201627375558
adenovirus serotype 5 vaccine vectors trigger il-27-dependent inhibitory cd4(+) t cell responses that impair cd8(+) t cell function.adenovirus serotype 5 (ad5) vaccine vectors elicit robust cd8(+) t cell responses, but these responses typically exhibit a partially exhausted phenotype. however, the immunologic mechanism by which ad5 vectors induce dysfunctional cd8(+) t cells has not previously been elucidated. here we demonstrate that, following immunization of b6 mice, ad5 vectors elicit antigen-specific il-10(+)cd4(+) t cells with a distinct transcriptional profile in a dose-dependent fashion. in rhesus monkeys, we similar ...201628239679
thermal inactivation and growth potential of listeria monocytogenes in smoked tench.an experimental study for the evaluation of listeria monocytogenes inactivation during a hot smoking process in tench was performed using listeria innocua strains. furthermore, the survival of l. monocytogenes in smoked tench was determined after post-processing in contaminated samples, evaluating the growth potential during storage. l innocua was not detected after the smoking process. in the challenge test, the growth potential of l. monocytogenes was 5.68 log colony forming unit g(-1). the re ...201627853718
the antimicrobial action of resveratrol against listeria monocytogenes in food-based models and its antibiofilm properties.resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural phytoalexin synthesized by plants in response to stress. this compound has several beneficial documented properties, namely anti-inflammatory, antioxidant, neuroprotective and antimicrobial activities. in this study the antimicrobial activity of resveratrol against listeria monocytogenes and listeria innocua was investigated.201626867522
various ready-to-eat products from retail stores linked to occurrence of diverse listeria monocytogenes and listeria spp. isolates.listeriosis outbreaks have been associated with a variety of foods. this study investigated the prevalence and diversity of listeria monocytogenes and listeria spp. in ready-to-eat (rte) products and evaluated the performance of a rapid detection method, the 3m molecular detection assay for l. monocytogenes (mda-lm), for detection of l. monocytogenes. assay results were compared with those obtained using the u.s. food and drug administration standard culture method described in the bacteriologic ...201626818984
assessment of listeria sp. interference using a molecular assay to detect listeria monocytogenes in food.detection of listeria monocytogenes in food is currently based on enrichment methods. when l. monocytogenes is present with other listeria species in food, the species compete during the enrichment process. overgrowth competition of the nonpathogenic listeria species might result in false-negative results obtained with the current reference methods. this potential issue was noted when 50 food samples artificially spiked with l. monocytogenes were tested with a real-time pcr assay and canada's cu ...201626735040
a computational study of amensalistic control of listeria monocytogenes by lactococcus lactis under nutrient rich conditions in a chemostat setting.we study a previously introduced mathematical model of amensalistic control of the foodborne pathogen listeria monocytogenes by the generally regarded as safe lactic acid bacteria lactococcus lactis in a chemostat setting under nutrient rich growth conditions. the control agent produces lactic acids and thus affects ph in the environment such that it becomes detrimental to the pathogen while it is much more tolerant to these self-inflicted environmental changes itself. the mathematical model con ...201628231156
identification of internalin-a-like virulent proteins in leishmania donovani.an active immune surveillance and a range of barriers to infection allow the host to effectively eliminate microbial pathogens. however, pathogens may use diverse strategies to subdue such host defences. for instance, one such mechanism is the use of leucine-rich repeat (lrr) proteins by pathogens (microbial) to cause infection. in this study, we aimed at identifying novel virulence factor(s) in leishmania donovani, based on the possibility of lateral gene transfers of bacterial virulence factor ...201627765050
topical simvastatin as host-directed therapy against severity of cutaneous leishmaniasis in mice.we recently demonstrated that statins mediate protection against intracellular pathogens, mycobacterium tuberculosis and listeria monocytogenes in mice. here, we investigated the immunomodulatory potential of simvastatin as a topical or systemic host-directed drug therapy in controlling inflammatory responses in an experimental mouse model of cutaneous leishmaniasis caused by leishmania major (lv39). in an ear infection model, topical application of simvastatin directly on established lesions si ...201627632901
expression of pd-1/lag-3 and cytokine production by cd4(+) t cells during infection with plasmodium parasites.cd4(+) t cells play critical roles in protection against the blood stage of malarial infection; however, their uncontrolled activation can be harmful to the host. in this study, in which rodent models of plasmodium parasites were used, the expression of inhibitory receptors on activated cd4(+) t cells and their cytokine production was compared with their expression in a bacterial and another protozoan infection. cd4(+) t cells from mice infected with p. yoelii 17xl, p yoelii 17xnl, p. chabaudi, ...201626696540
exploiting death: apoptotic immunity in microbial pathogenesis.innate immunity typically is responsible for initial host responses against infections. independently, nucleated cells that die normally as part of the physiological process of homeostasis in mammals (including humans) suppress immunity. specifically, the physiological process of cell death (apoptosis) generates cells that are recognized specifically by viable cells of all types and elicit a profound transient suppression of host immunity (termed 'innate apoptotic immunity' (iai)). iai appears t ...201626943319
mode of action of leucocin k7 produced by leuconostoc mesenteroides k7 against listeria monocytogenes and its potential in milk preservation.to investigate the mode of action of leucocin k7 against listeria monocytogenes and to assess its inhibitory effect on lis. monocytogenes in refrigerated milk.201627193759
controlling listeria monocytogenes and leuconostoc mesenteroides in uncured deli-style turkey breast using a clean label antimicrobial.interest in natural/organic meat products has resulted in the need to validate the effectiveness of clean label antimicrobials to increase safety and shelf life of these products. a response surface methodology (rsm) was used to investigate the effects of varying levels of moisture, ph, and a commercial "clean-label" antimicrobial (cultured sugar-vinegar blend; csvb) on the growth rate of listeria monocytogenes and leuconostoc mesenteroides in uncured turkey stored at 4 °c for 16 wk. twenty trea ...201626878335
genetic characterization of lactic acid bacteria isolated from tunisian milk waste and their antimicrobial activity against some bacteria implicated in nosocomial infections.a total of 94 lactic acid bacteria (lab) were isolated from tunisian artisanal (ricotta cheese's whey) and industrial (bactofugate) milk waste, identified and then screened for their antimicrobial activity against some bacteria implicated on nosocomial infections.201627449666
effects of the essential oil from origanum vulgare l. on survival of pathogenic bacteria and starter lactic acid bacteria in semihard cheese broth and slurry.this study assessed the inhibitory effects of the essential oil from origanum vulgare l. (oveo) on staphylococcus aureus, listeria monocytogenes, and a mesophilic starter coculture composed of lactic acid bacteria (lactococcus lactis subsp. lactis and l. lactis subsp. cremoris) in brazilian coalho cheese systems. the mic of oveo was 2.5 μl/ml against both s. aureus and l. monocytogenes and 0.6 μl/ml against the tested starter coculture. in cheese broth containing oveo at 0.6 μl/ml, no decrease i ...201626818985
control of listeria monocytogenes biofilms on industrial surfaces by the bacteriocin-producing lactobacillus sakei crl1862.the effect of the bacteriocin-producing lactobacillus sakei crl1862 and its bacteriocin in the control of listeria biofilm formation on industrial surfaces at 10°c was investigated. a screening among different listeria species was performed allowing selecting l. monocytogenes fbunt for its use as a biofilm producer on stainless steel (ss) and polytetrafluoroe-thylene (ptfe) surfaces. three conditions were simulated to evaluate the ability of the bacteriocinogenic strain to displace, exclude and ...201627190146
phenotypic and genotypic characterization of peptidoglycan hydrolases of lactobacillus sakei.lactobacillus sakei, a lactic acid bacterium naturally found in fresh meat and sea products, is considered to be one of the most important bacterial species involved in meat fermentation and bio-preservation. several enzymes of lb. sakei species contributing to microbial safeguarding and organoleptic properties of fermented-meat were studied. however, the specific autolytic mechanisms and associated enzymes involved in lb. sakei are not well understood. the autolytic phenotype of 22 lb. sakei st ...201626843981
development and anti-listerial activity of pe-based biological preservative films incorporating plantaricin bm-1.in recent years, bacteriocin as a natural antimicrobial compound, provides enormous promise to be used in food safety preservation. in this work, the polyethylene(pe)-based biological preservative films incorporating plantaricin bm-1, a typical iia bacteriocin produced by lactobacillus plantarum bm-1, were developed and characterized. the results showed that polyethylene (pe), low-density polyethylene (ldpe) and high-density polyethylene (hdpe) films soaked in plantaricin bm-1 solution had obvio ...201627993928
in vitro evaluation of beneficial properties of bacteriocinogenic lactobacillus plantarum st8sh.lactobacillus plantarum st8sh, isolated from bulgarian salami "shpek" and previously characterized as bacteriocin producer, was evaluated for its beneficial properties. based on the pcr analysis, lb. plantarum st8sh was shown to host a gene related to the production of adhesion proteins such as mab, mub, ef, and prgb. genetic and physiological tests suggest lb. plantarum st8sh to represent a potential probiotic candidate, including survival in the presence of low levels of ph and high levels of ...201627943050
the effect of different matrices on the growth kinetics and heat resistance of listeria monocytogenes and lactobacillus plantarum.microbial growth and inactivation kinetics in food can be predicted when the effects of food properties and environmental conditions on microbial responses are available. however the effects of these intrinsic and extrinsic variables on microbial kinetics are often obtained using laboratory media, and deviations between predictions and true behaviour might occur if the specific effect of a food product is not known or considered in the prediction. therefore, knowing the food specific effect on m ...201627723494
inhibition of listeria monocytogenes in hot dogs by surface application of freeze-dried bacteriocin-containing powders from lactic acid bacteria.six lactic acid bacteria (lab) strains, lactococcus lactis bfe 920, l. lactis subsp. lactis atcc 11454, l. lactis subsp. cremoris atcc 14365, lactobacillus curvatus l442, lact. curvatus lth 1174, and lact. bavaricus mn, were grown in cheddar cheese whey supplemented with complex nutrient sources. cell-free culture supernatants were freeze-dried, and the resulting bacteriocin-containing powders were applied on the surface of hot dogs that were inoculated (~4 log cfu/hot dog) with a five-strain li ...201627094263
in vitro evaluation of bacteriocins activity against listeria monocytogenes biofilm formation.the present study aimed to assess the activity of cell-free supernatant (cfs) containing bacteriocins on the formation and maintenance of biofilms developed by listeria monocytogenes, and the associated effect of bacteriocins and ethylene-diamine-tetra-acetic acid (edta) on the formed biofilm. cfs from 9 lactic acid bacteria (lab) strains was tested for inhibitory activity against 85 l. monocytogenes isolates and 21 lab strains. then, 12 l. monocytogenes strains were selected based on genetic pr ...201626660467
use of potential probiotic lactic acid bacteria (lab) biofilms for the control of listeria monocytogenes, salmonella typhimurium, and escherichia coli o157:h7 biofilms formation.use of probiotic biofilms can be an alternative approach for reducing the formation of pathogenic biofilms in food industries. the aims of this study were (i) to evaluate the probiotic properties of bacteriocinogenic (lactococcus lactis vb69, l. lactis vb94, lactobacillus sakei mbsa1, and lactobacillus curvatus mbsa3) and non-bacteriocinogenic (l. lactis 368, lactobacillus helveticus 354, lactobacillus casei 40, and weissela viridescens 113) lactic acid bacteria (lab) isolated from brazilian's f ...201627375584
antimicrobial hyaluronic acid-cefoxitin sodium thin films produced by electrospraying.the healing properties of hyaluronic acid (ha) in the recovery of wounds are well known. cefoxitin (cef), a cephalosporin antibiotic, is generally used to prevent and treat postoperative infections. in this study, we describe the incorporation of cef in ha thin films (cef-haf) by using electrospraying. scanning electron microscopy images showed that ha-containing thin films (haf) were composed of numerous nanoparticles (255 ± 177 nm in diameter) with irregular surfaces, connected to each other w ...201627146506
prophage-mediated modulation of interaction of streptococcus thermophilus j34 with human intestinal epithelial cells and its competition against human pathogens.the human intestinal microbiota plays an important role in human health. while adhesion to gastrointestinal mucosa is a prerequisite for colonisation, inhibition of adhesion is a property which may prevent or reduce infections by food borne pathogens. streptococcus thermophilus and lactobacillus delbrueckii subsp. bulgaricus represent the two lactic bacteria constituting the yoghurt culture. these starter cultures have been claimed to be probiotic. in our study we compared two s. thermophilus st ...201626689226
fermentation of african kale (brassica carinata) using l. plantarum bfe 5092 and l. fermentum bfe 6620 starter strains.vegetables produced in africa are sources of much needed micronutrients and fermentation is one way to enhance the shelf life of these perishable products. to prevent post-harvest losses and preserve african leafy vegetables, lactobacillus plantarum bfe 5092 and lactobacillus fermentum bfe 6620 starter strains were investigated for their application in fermentation of african kale (brassica carinata) leaves. they were inoculated at 1×10(7)cfu/ml and grew to a maximum level of 10(8)cfu/ml during ...201627614122
in vitro assessment of the antimicrobial potentials of lactobacillus helveticus strains isolated from traditional cheese in sinkiang china against food-borne pathogens.lactobacillus helveticus, an obligatory hetero-fermentative lab, is generally recognized as safe (gras) and is gaining popularity for application in dairy products. lactic acid bacteria (lab) play a remarkable role in inhibiting the growth of pathogenic bacteria in food products, without disturbing the sensory attributes of the food. in this study, the screening of the antimicrobial potential of lactobacillus helveticus klds 1.8701 against four food-borne pathogens including listeria monocytogen ...201626648272
physio-chemical, microbiological properties of tempoyak and molecular characterisation of lactic acid bacteria isolated from tempoyak.this study aims to determine physio-chemical properties of tempoyak, characterise the various indigenous species of lactic acid bacteria (lab) present at different stages of fermentation and also to determine the survival of selected foodborne pathogens in tempoyak. the predominant microorganisms present in tempoyak were lab (8.88-10.42 log cfu/g). fructobacillus durionis and lactobacillus plantarum were the dominant members of lab. other lab species detected for the first time in tempoyak were ...201627217364
investigating the effect of different treatments with lactic acid bacteria on the fate of listeria monocytogenes and staphylococcus aureus infection in galleria mellonella larvae.the use of galleria mellonella as a model host to elucidate microbial pathogenesis and search for novel drugs and therapies has been well appreciated over the past years. however, the effect of microorganisms with functional appeal in the specific host remains scarce. the present study investigates the effect of treatment with selected lactic acid bacteria (lab) with probiotic potential, as potential protective agents by using live or heat-killed cells at 6 and 24 h prior to infection with liste ...201627618619
serious infection during etanercept, infliximab and adalimumab therapy for rheumatoid arthritis: a literature review.the purpose of this review is to establish whether there is a significantly increased incidence of serious infections during treatment for rheumatoid arthritis (ra) with etanercept, infliximab or adalimumab, to determine the background risk of serious infection in ra patients without treatment with any biological therapy and to ascertain which organisms are involved in serious infections in ra patients while being treated with etanercept, infliximab or adalimumab. randomised controlled trials (r ...201626200188
enterococcus mundtii st4sa and lactobacillus plantarum 423 excludes listeria monocytogenes from the git, as shown by bioluminescent studies in mice.listeria monocytogenes is an opportunistic food-borne pathogen and is life-threatening to individuals with a weakened immune system. the aim of this study was to determine if lactobacillus plantarum 423 and enterococcus mundtii st4sa could prevent colonisation of l. monocytogenes in the gastro-intestinal tract (git). mice were gavaged with l. plantarum 423, e. mundtii st4sa, and a combination of the two strains, for 6 consecutive days and orally infected with a bioluminescent strain of l. monocy ...201626689230
manipulation of host membranes by the bacterial pathogens listeria, francisella, shigella and yersinia.bacterial pathogens display an impressive arsenal of molecular mechanisms that allow survival in diverse host niches. subversion of plasma membrane and cytoskeletal functions are common themes associated to infection by both extracellular and intracellular pathogens. moreover, intracellular pathogens modify the structure/stability of their membrane-bound compartments and escape degradation from phagocytic or autophagic pathways. here, we review the manipulation of host membranes by listeria mono ...201627448494
a stable live bacterial vaccine.formulating vaccines into a dry form enhances its thermal stability. this is critical to prevent administering damaged and ineffective vaccines, and to reduce its final cost. a number of vaccines in the market as well as those being evaluated in the clinical setting are in a dry solid state; yet none of these vaccines have achieved long-term stability at high temperatures. we used spray-drying to formulate a recombinant live attenuated listeria monocytogenes (lm; expressing francisella tularensi ...201627020530
listeria monocytogenes merr-like regulator nmlrlm: its transcriptome and role in stress response.nmlr, a negative transcription regulator in the merr family, is involved in oxidative and nitrosative stress response in neisseria gonorrhoeae and haemophilus influenzae. in this study, the objective was to characterize the role and the regulon of nmlr in the foodborne listeria monocytogenes. an l. monocytogenes nmlr null mutant strain was constructed. transcriptomes of strain 10403s wild type (wt) and δnmlrlm strains grown to the stationary phase were determined by mrna sequencing. differential ...201627058117
the noa gene is functionally linked to the activation of the toll/imd signaling pathways in bactrocera dorsalis (hendel).the noa gene is an essential gene encoding a very long chain fatty acid elongase. in this study, we cloned the noa gene of bactrocera dorsalis, which encodes a protein sharing 84.50% identity to the noa in drosophila melanogaster. the expression profiles indicated that the transcriptional level of noa was high at the egg stage and in the testis tissue. the results showed that noa expression was up-regulated after listeria monocytogenes, staphylococcus aureus and escherichia coli infection. silen ...201626404497
commercially available rapid methods for detection of selected food-borne pathogens.generally, the enumeration and isolation of food-borne pathogens is performed using culture-dependent methods. these methods are sensitive, inexpensive, and provide both qualitative and quantitative assessment of the microorganisms present in a sample, but these are time-consuming. for this reason, researchers are developing new techniques that allow detection of food pathogens in shorter period of time. this review identifies commercially available methods for rapid detection and quantification ...201625749054
real-time investigation of antibiotics-induced oxidative stress and superoxide release in bacteria using an electrochemical biosensor.the involvement of oxidative stress in the mechanism of antibiotics-meditated cell death is unclear and subject to debate. the kinetic profile and a quantitative relationship between the release of reactive oxygen species (ros), bacteria and antibiotic type remain elusive. here we report direct measurements and analytical quantification of the release of superoxide radicals (o2(·-)), a major contributor to ros, in antibiotics-treated bacterial cultures using a cytochrome c electrochemical biosen ...201626655038
biofabrication of zinc oxide nanoparticles using fruit extract of rosa canina and their toxic potential against bacteria: a mechanistic approach.the use of plant extract in the biosynthesis of nanoparticles (nps) can be an eco-friendly approach and have been suggested as a possible alternative to classic methods namely physical and chemical procedures. in this study, the biosynthesis of zinc oxide (zno) nps by both "conventional heating" (ch) and "microwave irradiation" (mi) methods has been reported. stable and spherical znonps were produced using zinc nitrate and flesh extract of rosa canina fruit (rosehip) which was used as a precurso ...201626652376
bactericidal action mechanism of negatively charged food grade clove oil nanoemulsions.clove oil (co) anionic nanoemulsions were prepared with varying ratios of co to canola oil (ca), emulsified and stabilized with purity gum ultra (pgu), a newly developed succinylated waxy maize starch. interfacial tension measurements showed that co acted as a co-surfactant and there was a gradual decrease in interfacial tension which favored the formation of small droplet sizes on homogenization until a critical limit (5:5% v/v co:ca) was reached. antimicrobial activity of the negatively charge ...201626616926
the effect of nacl reduction in the microbiological quality of cracked green table olives of the maçanilha algarvia cultivar.the present work aimed at studying the effect of the partial replacement of nacl with kcl and cacl2 of the fermenting brines on the microbiological quality of natural cracked green maçanilha algarvia table olives. olives were fermented in different salt combinations (brine 1-8% nacl, brine 2-4% nacl 4% kcl, brine 3-4% nacl 4% cacl2, brine 4-4% kcl 4% cacl2, and brine 5-2.7% nacl 2.7% kcl 2.7% cacl2) and the abundance of yeasts and enterobacteria was determined. at the end of fermentation, the ma ...201626613162
characterization of a transferable bcrabc and cadac genes-harboring plasmid in listeria monocytogenes strain isolated from food products of animal origin.in this study, we characterized a bcrabc cassette and its genetic environment harbored by a plasmid in listeria monocytogenes (l. monocytogenes) 11gzl18, a strain isolated from raw meat in 2011. the bcrabc cassette and its genetic environment were characterized, with a total of 33,727 nt nucleotide sequence obtained. the nucleotide sequences of the bcrabc cassette in strain 11gzl18 exhibited 100% identity to that on plasmid plm80, which is harbored by l. monocytogenes strain h7550 and h7858, and ...201626513251
lactobacillus plantarum lb95 impairs the virulence potential of gram-positive and gram-negative food-borne pathogens in ht-29 and vero cell cultures.listeria monocytogenes, salmonella enterica and verocytotoxigenic escherichia coli (vtec) are amongst the most important agents responsible for food outbreaks occurring worldwide. in this work, two lactobacillus spp. strains (labs), lactobacillus plantarum (lb95) and lactobacillus paraplantarum (lb13), previously isolated from spontaneously fermenting olive brines, and two reference probiotic strains, lactobacillus casei shirota and lactobacillus rhamnosus gg, were investigated for their ability ...201626506821
development of prototypes of bioactive packaging materials based on immobilized bacteriophages for control of growth of bacterial pathogens in foods.due to lack of adequate control methods to prevent contamination in fresh produce and growing consumer demand for natural products, the use of bacteriophages has emerged as a promising approach to enhance safety of these foods. this study sought to control listeria monocytogenes in cantaloupes and rte meat and escherichia coli o104:h4 in alfalfa seeds and sprouts under different storage conditions by using specific lytic bacteriophage cocktails applied either free or immobilized. bacteriophage c ...201626490649
pathogen-nematode interaction: nitrogen supply of listeria monocytogenes during growth in caenorhabditis elegans.listeria monocytogenes is a gram-positive facultatively intracellular human pathogen. due to its saprophytic lifestyle, l. monocytogenes is assumed to infect and proliferate within soil organisms such as caenorhabditis elegans. however, little is known about the nutrient usages and metabolite fluxes in this bacterium-nematode interaction. here, we established a nematode colonization model for l. monocytogenes and a method for the efficient separation of the pathogen from the nematodal gut. follo ...201626478569
development of bioactive fish gelatin/chitosan nanoparticles composite films with antimicrobial properties.the objective of this work was to develop active bio-based nanocomposite films from fish gelatin (fg) and chitosan nanoparticles (csnps) incorporated with origanum vulgare l. essential oil (oeo). csnps were obtained by ionic gelation of chitosan with sodium tripolyphosphate, which presented a spherical morphology with size range of 40-80nm. remarkable differences in the surface morphology were observed between the control and bioactive nanocomposite films as revealed by sem and afm images. ftir ...201626471681
streptococcus gallolyticus (bovis): a rare presentation of meningitis in the ed.bacterial meningitis is a fairly common and often deadly manifestation of altered mental status in the elderly, carrying a mortality rate of greater than 20% despite antibiotic therapy. most commonly caused by streptococcus pneumoniae, listeria monocytogenes, escherichia coli, and klebsiella pneumoniae. we present a case of meningitis caused by streptococcus gallolyticus in an elderly, otherwise healthy woman. there have been no reports in the emergency medicine literature and only a few reports ...201626259921
cationic nanostructures against foodborne pathogens. 201627881979
antibacterial potential of jatropha curcas synthesized silver nanoparticles against food borne pathogens.the aqueous leaf extract of jatropha curcas was used for the synthesis of silver nanoparticles (jc-agnps) which were further evaluated for its antibacterial potential against food borne pathogens. j. curcas leaf extract could synthesize stable silver nanoparticles (zeta potential: -23.4 mv) with absorption band at 430 nm. fourier transform infrared spectroscopy indicated various biological compounds responsible for capping and stabilizing jc-agnps in suspension, while the presence of silver was ...201627877160
electrochemical genosensing of salmonella, listeria and escherichia coli on silica magnetic particles.a magneto-genosensing approach for the detection of the three most common pathogenic bacteria in food safety, such as salmonella, listeria and escherichia coli is presented. the methodology is based on the detection of the tagged amplified dna obtained by single-tagging pcr with a set of specific primers for each pathogen, followed by electrochemical magneto-genosensing on silica magnetic particles. a set of primers were selected for the amplification of the inva (278 bp), prfa (217 bp) and eaea ...201626724759
isotopologue profiling of the listerial n-metabolism.the nitrogen (n-) sources and the relative contribution of a nitrogenous nutrient to the n-pool of the gram-positive pathogen listeria monocytogenes are largely unknown. therefore, (15) n-isotopologue profiling was established to study the n-metabolism of l. monocytogenes. the pathogen was grown in a defined minimal medium supplemented with potential (15) n-labeled nutrients. the bacteria were harvested and hydrolysed under acidic conditions, and the resulting amino acids were analysed by gc-ms, ...201626699934
methodology for identification of pore forming antimicrobial peptides from soy protein subunits β-conglycinin and glycinin.antimicrobial peptides (amps) inactivate microbial cells through pore formation in cell membrane. because of their different mode of action compared to antibiotics, amps can be effectively used to combat drug resistant bacteria in human health. amps can also be used to replace antibiotics in animal feed and immobilized on food packaging films. in this research, we developed a methodology based on mechanistic evaluation of peptide-lipid bilayer interaction to identify amps from soy protein. produ ...201627612614
in vitro activity of plant extracts against biofilm-producing food-related bacteria.the identification of effective antimicrobial agents also active on biofilms is a topic of crucial importance in food and industrial environment. for that purpose methanol extracts of turkish plants, ficus carica l., juglans regia l., olea europaea l., punica granatum l. and rhus coriaria l., were investigated. among the extracts, p. granatum l. and r. coriaria l. showed the best antibacterial activity with minimum inhibitory concentrations (mic) of 78-625μg/ml for listeria monocytogenes and sta ...201627591384
a counterselection method for lactococcus lactis genome editing based on class iia bacteriocin sensitivity.in this paper, we present a new counterselection method for deleting fragments from lactococcus lactis chromosome. the method uses a non-replicating plasmid vector, which integrates into the chromosome and makes the cell sensitive to bacteriocins. the integration vector carries puc ori functional in escherichia coli but not in l. lactis, an erythromycin resistance gene for selecting single crossover integrants, and two fragments from l. lactis chromosome for homologous recombinations. in additio ...201627654656
reduced susceptibilities to biocides and resistance to antibiotics in food-associated bacteria following exposure to quaternary ammonium compounds.our aim was to assess the effects of step-wise exposure to didecyl dimethyl ammonium chloride (ddac) on the antimicrobial (antibiotics and biocides) susceptibilities of food-associated bacterial strains.201627481186
microfluidic cantilever detects bacteria and measures their susceptibility to antibiotics in small confined volumes.in the fight against drug-resistant bacteria, accurate and high-throughput detection is essential. here, a bimaterial microcantilever with an embedded microfluidic channel with internal surfaces chemically or physically functionalized with receptors selectively captures the bacteria passing through the channel. bacterial adsorption inside the cantilever results in changes in the resonance frequency (mass) and cantilever deflection (adsorption stress). the excitation of trapped bacteria using inf ...201627698375
identification of lactic acid bacteria in fruit pulp processing byproducts and potential probiotic properties of selected lactobacillus strains.this study aimed to identify lactic acid bacteria (lab) in byproducts of fruit (malpighia glabra l., mangifera indica l., annona muricata l., and fragaria vesca l.) pulp processing. fifty strains of lab were identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (maldi-tof ms) and 16s rrna gene sequence (16s rrna) analysis. species belonging to lactobacillus genus were the predominant lab in all fruit pulp processing byproducts. the average congruency betwe ...201627625647
comprehensive evaluation and implementation of improvement actions in butcher shops.foodborne pathogens can cause acute and chronic diseases and produce a wide range of symptoms. since the consumption of ground beef is a risk factor for infections with some bacterial pathogens, we performed a comprehensive evaluation of butcher shops, implemented improvement actions for both butcher shops and consumers, and verified the impact of those actions implemented. a comprehensive evaluation was made and risk was quantified on a 1-100 scale as high-risk (1-40), moderate-risk (41-70) or ...201627618439
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