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whole genome sequencing analyses of listeria monocytogenes that persisted in a milkshake machine for a year and caused illnesses in washington state.in 2015, in addition to a united states multistate outbreak linked to contaminated ice cream, another outbreak linked to ice cream was reported in the pacific northwest of the united states. it was a hospital-acquired outbreak linked to milkshakes, made from contaminated ice cream mixes and milkshake maker, served to patients. here we performed multiple analyses on isolates associated with this outbreak: pulsed-field gel electrophoresis (pfge), whole genome single nucleotide polymorphism (snp) a ...201728619007
development of biopolymer composite films using a microfluidization technique for carboxymethylcellulose and apple skin particles.biopolymer films based on apple skin powder (asp) and carboxymethylcellulose (cmc) were developed with the addition of apple skin extract (ase) and tartaric acid (ta). asp/cmc composite films were prepared by mixing cmc with asp solution using a microfluidization technique to reduce particle size. then, various concentrations of ase and ta were incorporated into the film solution as an antioxidant and an antimicrobial agent, respectively. fourier transform infrared (ftir), optical, mechanical, w ...201728617325
influence of food characteristics and food additives on the antimicrobial effect of garlic and oregano essential oils.utilization of essential oils (eos) as antimicrobial agents against foodborne disease has gained importance, for their use as natural preservatives. since potential interactions between eos and food characteristics may affect their antimicrobial properties, the present work studies the influence of fat, protein, ph, aw and food additives on the antimicrobial effect of oregano and garlic eos against salmonella spp. and listeria monocytogenes. results showed that protein, ph, aw, presence of beef ...201728604598
how the study of listeria monocytogenes has led to new concepts in biology.the opportunistic intracellular bacterial pathogen listeria monocytogenes has in 30 years emerged as an exceptional bacterial model system in infection biology. research on this bacterium has provided considerable insight into how pathogenic bacteria adapt to mammalian hosts, invade eukaryotic cells, move intracellularly, interfere with host cell functions and disseminate within tissues. it also contributed to unveil features of normal host cell pathways and unsuspected functions of previously k ...201728604108
persistent listeria monocytogenes strains isolated from mussel production facilities form more biofilm but are not linked to specific genetic markers.contamination of mussels with the human pathogen listeria monocytogenes occurs during processing in the factory, possibly from bacteria persisting in the factory's indoor and outdoor areas. in this study, a selection of persistent (n=8) and sporadic (n=8) l. monocytogenes isolates associated with mussel-processing premises in new zealand were investigated for their phenotypic and genomic characteristics. to identify traits that favour or contribute to bacterial persistence, biofilm formation, he ...201728599174
comparison of the in vitro activity of ampicillin and moxifloxacin against listeria monocytogenes at achievable concentrations in the central nervous system.the aim of this study was to compare the in vitro activity of ampicillin and moxifloxacin against six isolates selected from 154 invasive clinical isolates of listeria monocytogenes and evaluate their intra- and extracellular activities with achievable central nervous system concentrations obtained using monte carlo simulations with conventional and unconventional dosages.201728598305
mathematical model of interaction between bacteriocin-producing lactic acid bacteria and listeria. part 1: steady states and thresholds.mathematical modeling is an important tool to assessing quantitative conjectures and to answer specific questions. in the modeling, we assume that a competitor represented by a lactic acid bacterium produces antimicrobial compounds (substances that kill microorganisms or inhibit their growth), such as lactic acid and bacteriocins, with some cost to its own growth. bacteriocins are protein compounds with antimicrobial effect against related species and bacteria such as listeria monocytogenes, whi ...201728597170
inhibition strategies of listeria monocytogenes biofilms-current knowledge and future outlooks.there is an increasing trend in the food industry on the listeria monocytogenes biofilm formation and inhibition. this is attributed to its easy survival on contact surfaces, resistance to disinfectants or antibiotics and growth under the stringent condition used for food processing and preservation thereby leading to food contamination products by direct or indirect exposure. though, there is a lack of conclusive evidences about the mechanism of biofilm formation, in this review, the concept of ...201728594071
commensal microbes provide first line defense against listeria monocytogenes infection.listeria monocytogenes is a foodborne pathogen that causes septicemia, meningitis and chorioamnionitis and is associated with high mortality. immunocompetent humans and animals, however, can tolerate high doses of l. monocytogenes without developing systemic disease. the intestinal microbiota provides colonization resistance against many orally acquired pathogens, and antibiotic-mediated depletion of the microbiota reduces host resistance to infection. here we show that a diverse microbiota mark ...201728588016
longitudinal monitoring of listeria monocytogenes and listeria phages in seafood processing environments in thailand.listeria monocytogenes is a foodborne pathogen commonly found in environments of seafood processing, thus presenting a challenge for eradication from seafood processing facilities. monitoring the prevalence and subtype diversity of l. monocytogenes together with phages that are specific to listeria spp. ("listeria phages") will provide knowledge on the bacteria-phage ecology in food processing plants. in this work, a total of 595 samples were collected from raw material, finished seafood product ...201728576358
empiric listeria monocytogenes antibiotic coverage for febrile infants (age, 0-90 days). 201728574538
genome-wide-analyses of listeria monocytogenes from food-processing plants reveal clonal diversity and date the emergence of persisting sequence types.whole genome sequencing is increasing used in epidemiology, e.g. for tracing outbreaks of food-borne diseases. this requires in-depth understanding of pathogen emergence, persistence and genomic diversity along the food production chain including in food processing plants. we sequenced the genomes of 80 isolates of listeria monocytogenes sampled from danish food processing plants over a time-period of 20 years, and analysed the sequences together with 10 public available reference genomes to adv ...201728574206
draft genome sequences of listeria monocytogenes, isolated from fresh leaf vegetables in owerri city, nigeria.here, we report the draft genome sequences of three listeria monocytogenes isolates from fresh leaves collected in nigeria, belonging to sequence types st5 and st155 (sublineages sl5 and sl155, respectively).201728572306
curcumin promotes the clearance of listeria monocytogenes both in vitro and in vivo by reducing listeriolysin o oligomers.the pore-forming toxin listeriolysin o (llo), an essential virulence factor that is secreted by listeria monocytogenes (l. monocytogenes), is responsible for bacterial breaching at the phagosomal membranes and subsequent release into the cytoplasm; it cannot be recognized by the host immune system. the vital role that llo plays in bacterial pathogenicity and evading host immune clearance makes this virulence a promising target for addressing l. monocytogenes infection. in this study, we hypothes ...201728567044
impact of nutrient restriction on the structure of listeria monocytogenes biofilm grown in a microfluidic system.biofilm formation by the pathogen listeria monocytogenes is a major concern in food industries. the aim of this work was to elucidate the effect of nutrient limitation on both biofilm architecture and on the viability of the bacteria in microfluidic growth conditions. biofilm formation by two l. monocytogenes strains was performed in a rich medium (bhi) and in a 10-fold diluted bhi (bhi/10) at 30°c for 24 h by using both static conditions and the microfluidic system bioflux. in dynamic condition ...201728567031
naïve helper t cells with high cd5 expression have increased calcium signaling.the adaptive immune response is orchestrated by t helper cells and their function is dependent upon interactions between the t cell receptor (tcr), peptide mhc (pmhc) and co-receptors. tcr-pmhc interactions initiate calcium signaling cascades which determine t cell activation, survival, proliferation and differentiation. cd5 is a co-receptor that plays an important role in regulating t cell signaling and fate during thymocyte education. cd5 surface expression on mature single positive thymocytes ...201728562659
deciphering the landscape of host barriers to listeria monocytogenes infection.listeria monocytogenes is a common food-borne pathogen that can disseminate from the intestine and infect multiple organs. here, we used sequence tag-based analysis of microbial populations (stamp) to investigate lmonocytogenes population dynamics during infection. we created a genetically barcoded library of murinized lmonocytogenes and then used deep sequencing to track the pathogen's dissemination routes and quantify its founding population (nb) sizes in different organs. we found that the pa ...201728559314
whole genome and core genome multilocus sequence typing and single nucleotide polymorphism analyses of listeria monocytogenes associated with an outbreak linked to cheese, united states, 2013.epidemiological findings of a listeriosis outbreak in 2013 implicated hispanic-style cheese produced by company a, and pulsed-field gel electrophoresis (pfge) and whole genome sequencing (wgs) were performed on clinical isolates and representative isolates collected from company a cheese and environmental samples during the investigation. the results strengthened the evidence for cheese as the vehicle. surveillance sampling and wgs three months later revealed that the equipment purchased by comp ...201728550058
erratum: uncovering listeria monocytogenes hypervirulence by harnessing its biodiversity. 201728546578
the absence of tnf permits myeloid arginase 1 expression in experimental l. monocytogenes infection.during an immune response inflammatory macrophages with their wide variety of effector mechanisms including the expression of inducible nitric oxide synthase play an important part in the defense against invading pathogens. the inflammatory phenotype requires the presence of tnf which suppresses alternative activation. in the bacterial listeria monocytogenes infection model inflammatory macrophages are crucial for protection. after infection, tnf-deficient hosts have a similar number of splenic ...201728545808
down regulation of macrophage ifngr1 exacerbates systemic l. monocytogenes infection.interferons (ifns) target macrophages to regulate inflammation and resistance to microbial infections. the type ii ifn (ifnγ) acts on a cell surface receptor (ifngr) to promote gene expression that enhance macrophage inflammatory and anti-microbial activity. type i ifns can dampen macrophage responsiveness to ifnγ and are associated with increased susceptibility to numerous bacterial infections. the precise mechanisms responsible for these effects remain unclear. type i ifns silence macrophage i ...201728542482
invasive listeria monocytogenes gastroenteritis leading to stupor, bacteremia, fever, and diarrhea: a rare life-threatening condition.listeria monocytogenes is a gram-positive, rod-shaped organism that can cause serious infections such as meningitis, invasive gastroenteritis, and endocarditis. every year 1600 people in the united states are affected, with significant mortality of 260 people annually. listeria gastroenteritis has the third highest mortality rate among all the food-borne infection. invasive listeriosis most commonly affect pregnant women, those in extremes of ages, people with comorbid diseases, and people with ...201728540315
listeriosis during pregnancy.listeriosis is a rare foodborne illness caused by listeria monocytogenes. it can be transmitted by consuming contaminated ready-to-eat food, long shelf-life products, deli meats, and soft cheeses. listeria has a predilection to affect immunocompromised patients, elderly people, pregnant women and neonates. in particular, pregnant women are at ~18 times greater risk of infection than general population due to specific pregnancy-related suppressed cell-mediated immunity and placental tropism of l. ...201728536811
listeria monocytogenes bacteraemia over an 11-year period: clinical and epidemiologic characteristics in the south area of madrid. 201728527675
effects of parsley extract powder as an alternative for the direct addition of sodium nitrite in the production of mortadella-type sausages - impact on microbiological, physicochemical and sensory aspects.increasing concern about chemical additives in processed meat has led to an increased market of uncured and alternatively cured meat products. however, the use of vegetable extracts or the exclusion of curing salt may increase the risk of greater bacterial growth and alteration of several physicochemical parameters. therefore, in this study mortadella-type sausages, manufactured with 1.07 (v3), 2.14 (v4) and 4.29 (v5) g parsley extract powder/kg sausage meat were produced. these sausage variants ...201728527368
a novel role of listeria monocytogenes membrane vesicles in inhibition of autophagy and cell death.bacterial membrane vesicle (mv) production has been mainly studied in gram-negative species. in this study, we show that listeria monocytogenes, a gram-positive pathogen that causes the food-borne illness listeriosis, produces mvs both in vitro and in vivo. we found that a major virulence factor, the pore-forming hemolysin listeriolysin o (llo), is tightly associated with the mvs, where it resides in an oxidized, inactive state. previous studies have shown that llo may induce cell death and auto ...201728516064
isolation and characterization of listeria phages for control of growth of listeria monocytogenes in milk.in this study, two listeria bacteriophages, lmp1 and lmp7, were isolated from chicken feces as a means of biocontrol of l. monocytogenes. both bacteriophages had a lytic effect on l. monocytogenes atcc 7644, 15313, 19114, and 19115. phages lmp1 and lmp7 were able to inhibit the growth of l. monocytogenes atcc 7644 and 19114 in tryptic soy broth at 10°c and 30°c. nevertheless, lmp1 was more effective than lmp7 at inhibiting l. monocytogenes atcc 19114. on the contrary, lmp7 was more effective tha ...201728515656
assessment of microbial and radioactive contaminations in korean cold duck meats and electron-beam application for quality improvement.animal-origin food products pose serious threat to public food safety due to high microbial loads. the microbial and radioactive contaminations in commercial cold duck meat products were evaluated. ten different lots of commercial samples (c1-c10) were classified based on type and smoking process. all samples were highly contaminated (< 4-7 log cfu/g) with total aerobic bacteria (tab), yeasts and molds (y&m), and 7 samples (c1-c7) were positive for coliforms. furthermore, three samples were cont ...201728515653
unusual listeria monocytogenes peritonitis in peritoneal dialysis patient with liver cirrhosis: a case report and review of literature.spontaneous listeria peritonitis is well described in liver failure, but is uncommon in peritoneal dialysis patients. atypical cases where peritonitis symptoms develop after systemic manifestations are rare and challenging for diagnostic. a 57-year-old peritoneal dialysis patient with history of ethylic cirrhosis was admitted after epileptic seizure. on admission, patient was soporous without signs of peritonitis and meningitis. patient's peritoneal effluent was clear, with normal leukocytes. cr ...201728509139
tetr-dependent gene regulation in intracellular listeria monocytogenes demonstrates the spatiotemporal surface distribution of acta.to enable specific and tightly controlled gene expression both in vitro and during the intracellular lifecycle of the pathogen listeria monocytogenes, a tetr-dependent genetic induction system was developed. highest concentration of cytoplasmic tetr and best repression of teto-controlled genes was obtained by tetr expression from the synthetic promoter pt17 . anhydrotetracycline (atc) as inducer permitted concentration-dependent, fine-tuned expression of genes under control of the teto operator ...201728508453
limited colonization undermined by inadequate early immune responses defines the dynamics of decidual listeriosis.the bacterial pathogen listeria monocytogenes causes foodborne systemic disease in pregnant women, which can lead to preterm labor, stillbirth, or severe neonatal disease. colonization of the maternal decidua appears to be an initial step in the maternal component of the disease as well as bacterial transmission to the placenta and fetus. host-pathogen interactions in the decidua during this early stage of infection remain poorly understood. here, we assessed the dynamics of l. monocytogenes inf ...201728507070
spontaneous bacterial peritonitis due to listeria monocytogenes: always to be remembered. 201728502590
identification of a major listeria monocytogenes outbreak clone linked to soft cheese in northern italy - 2009-2011.molecular subtyping and enhanced surveillance in lombardy region identified a cluster of possibly related listeriosis cases from 2006 to 2010. this cluster grouped 31 isolates that belonged to serotype 1/2a and sequence type 38 (st38) as defined by multilocus sequence typing (mlst).201728499357
mtorc1 regulates mannose-6-phosphate receptor transport and t-cell vulnerability to regulatory t cells by controlling kinesin kif13a.mannose-6-phosphate receptor (m6pr) that facilitates cellular uptake of m6p-bearing proteins, including serine-protease granzyme-b (gzm-b) has an important role in t-cell activation, migration and contraction. however, molecular mechanisms controlling m6pr expression in t cells remain poorly understood. here, we show that m6pr expression on t cells is distinctively controlled by two common γ-chain cytokines interleukin-2 (il-2) and il-7, and the differential m6pr expression is not caused by an a ...201728496990
genome sequences of listeria monocytogenes strains with resistance to arsenic.listeria monocytogenes frequently exhibits resistance to arsenic. we report here the draft genome sequences of eight genetically diverse arsenic-resistant l. monocytogenes strains from human listeriosis and food-associated environments. the availability of these genomes will help elucidate the role of heavy-metal resistance in the ecology of l. monocytogenes.201728495780
complete genome sequences of 12 isolates of listeria monocytogenes belonging to serotypes 1/2a, 1/2b, and 4b obtained from food products and food-processing environments in canada.listeria monocytogenes is the etiological agent for an often fatal foodborne illness known as listeriosis. here, we present the complete genome sequences of 12 l. monocytogenes isolates representing the three most common serotypes of this pathogen (1/2a, 1/2b, and 4b), collected in canada from different food products and environmental sources.201728495767
draft genome sequences of 25 listeria monocytogenes isolates associated with human clinical listeriosis in ireland.listeria monocytogenes is a gram-positive opportunistic pathogen that is the causative agent of listeriosis. here, we report the draft genome sequences of 25 l. monocytogenes strains isolated from patients with clinical listeriosis in the republic of ireland between 2013 and 2015.201728495762
listeria endocarditis: a diagnostic challenge.a 74-year-old hemodialysis patient with a history of an atrial septum defect closure, coronary bypass surgery, and a st. jude aortic prosthetic valve was diagnosed with pneumonia and volume overload. blood cultures were positive for listeria monocytogenes, and amoxicillin was given for 2 weeks. immediately after discontinuation of amoxicillin, fever relapsed. transthoracic and transesophageal echocardiography showed no sign of endocarditis. given the fever relapse and 3 positive minor duke crite ...201728491879
characteristics and outcome of spontaneous bacterial meningitis in patients with cancer compared to patients without cancer.in cancer patients, who are frequently immunocompromised, bacterial meningitis (bm) can be a severe complication, with a different presentation, etiology, and course, compared to patients without cancer. our objective is to compare the characteristics and outcomes of bm in patients with and without cancer. a single-center, prospective observational cohort study, conducted between 1982 and 2012, in a tertiary university hospital in barcelona (spain). the main outcome measure is in-hospital mortal ...201728489800
analysis of listeria using exogenous volatile organic compound metabolites and their detection by static headspace-multi-capillary column-gas chromatography-ion mobility spectrometry (shs-mcc-gc-ims).listeria monocytogenes is a gram-positive bacterium and an opportunistic food-borne pathogen which poses significant risk to the immune-compromised and pregnant due to the increased likelihood of acquiring infection and potential transmission of infection to the unborn child. conventional methods of analysis suffer from either long turn-around times or lack the ability to discriminate between listeria spp. reliably. this paper investigates an alternative method of detecting listeria spp. using t ...201728484808
suppression of autoimmune demyelinating disease by preferential stimulation of cns-specific cd8 t cells using listeria-encoded neuroantigen.cd8 t-cells predominate in cns lesions of ms patients and display oligoclonal expansion. however, the role of myelin-specific cd8 t-cells in disease remains unclear, with studies showing protective and pathogenic roles in eae. we demonstrated a disease-suppressive function for cns-specific cd8 t-cells in a model where the antigen is exogenously administered in vivo and used for in vitro activation. to probe the nature of the cd8 response elicited by endogenously presented myelin antigens in vivo ...201728484224
label-free immuno-sensors for the fast detection of listeria in food.foodborne diseases are a major concern for both food industry and health organizations due to the economic costs and potential threats for human lives. for these reasons, specific regulations impose the research of pathogenic bacteria in food products. nevertheless, current methods, references and alternatives, take up to several days and require many handling steps. in order to improve pathogen detection in food, we developed an immune-sensor, based on surface plasmon resonance imaging (spri) a ...201728478556
a novel typing method for listeria monocytogenes using high-resolution melting analysis (hrma) of tandem repeat regions.listeria monocytogenes, which is responsible for causing food poisoning known as listeriosis, infects humans and animals. widely distributed in the environment, this bacterium is known to contaminate food products after being transmitted to factories via raw materials. to minimize the contamination of products by food pathogens, it is critical to identify and eliminate factory entry routes and pathways for the causative bacteria. high resolution melting analysis (hrma) is a method that takes adv ...201728475927
inll from listeria monocytogenes is involved in biofilm formation and adhesion to mucin.the bacterial etiological agent of listeriosis, listeria monocytogenes, is an opportunistic intracellular foodborne pathogen. the infection cycle of l. monocytogenes is well-characterized and involves several key virulence factors, including internalins a and b. while 35 genes encoding internalins have been identified in l. monocytogenes, less than half of them have been characterized as yet. focusing on lmo2026, it was shown this gene encodes a class i internalin, inll, exhibiting domains poten ...201728473809
listeria monocytogenes meningitis: pcr multiplex diagnosis. 201728473173
comparative genomics of human and non-human listeria monocytogenes sequence type 121 strains.the food-borne pathogen listeria (l.) monocytogenes is able to survive for months and even years in food production environments. strains belonging to sequence type (st)121 are particularly found to be abundant and to persist in food and food production environments. to elucidate genetic determinants characteristic for l. monocytogenes st121, we sequenced the genomes of 14 st121 strains and compared them with currently available l. monocytogenes st121 genomes. in total, we analyzed 70 st121 geno ...201728472116
lentinan from shiitake selectively attenuates aim2 and non-canonical inflammasome activation while inducing pro-inflammatory cytokine production.lentinan extracted from shiitake (lentinula edodes) is a β-glucan that has been reported as an intravenous anti-tumor polysaccharide via enhancement of the host immune system. in this study, we determined the effect of lentinan on inflammasome activation, a multi-protein platform, in myeloid cells. mouse bone marrow-derived macrophages were treated with lentinan with/without inflammasome triggers, and maturation of interleukin (il)-1β, il-18, or caspase-1 was measured as a readout of inflammasom ...201728465544
a clade of listeria monocytogenes serotype 4b variant strains linked to recent listeriosis outbreaks associated with produce from a defined geographic region in the us.four listeriosis incidences/outbreaks, spanning 19 months, have been linked to listeria monocytogenes serotype 4b variant (4bv) strains. three of these incidents can be linked to a defined geographical region, while the fourth is likely to be linked. in this study, whole genome sequencing (wgs) of strains from these incidents was used for genomic comparisons using two approached. the first was jspecies tetramer, which analyzed tetranucleotide frequency to assess relatedness. the second, the cfsa ...201728464038
analysis of process factors of dry fermented salami to control listeria monocytogenes.challenge tests are a clear opportunity for manufacturers interested in the evaluation of their management system with the aim to reduce the spread of foodborne pathogens. this is a main concern especially in ready-to-eat food in relation to the risk associated with listeria monocytogenes. for small and medium-scale food industry the manufacturing practices and products formulation are characterised by a wider variability and poor repeatability. the use of ad hoc challenge test and the compariso ...201728462203
host serine/threonine kinases mtor and protein kinase c-α promote inlb-mediated entry of listeria monocytogenes.the bacterial pathogen listeria monocytogenes causes foodborne illnesses resulting in gastroenteritis, meningitis, or abortion. listeria induces its internalization into some human cells through interaction of the bacterial surface protein inlb with the host receptor tyrosine kinase met. inlb-dependent entry requires localized polymerization of the host actin cytoskeleton. the signal transduction pathways that act downstream of met to regulate actin filament assembly or other processes during li ...201728461391
listeria monocytogenes-induced endogenous endophthalmitis in an otherwise healthy.purpose listeria monocytogenes is a rare cause of endogenous endophthalmitis. to date 15 cases have been published in the literature. all eyes showed similar clinical features and profound visual loss mainly due to delayed diagnosis.201728226136
pathological findings in the red fox (vulpes vulpes), stone marten (martes foina) and raccoon dog (nyctereutes procyonoides), with special emphasis on infectious and zoonotic agents in northern germany.anthropogenic landscape changes contributed to the reduction of availability of habitats to wild animals. hence, the presence of wild terrestrial carnivores in urban and peri-urban sites has increased considerably over the years implying an increased risk of interspecies spillover of infectious diseases and the transmission of zoonoses. the present study provides a detailed characterisation of the health status of the red fox (vulpes vulpes), stone marten (martes foina) and raccoon dog (nyctereu ...201728399176
pregnancy-related listeriosis.about one in seven cases of listeriosis occurs in pregnant women, and, although listeriosis is rare, it is the third leading cause of death from food-borne infections. pregnancy-related listeriosis increases the risk for fetal and neonatal mortality by approximately 21%. during pregnancy, infections are more likely to occur in the third trimester (66%) than the first trimester (3%). however, fetal and neonatal adverse effects are less common as gestational age increases or with older gestational ...201728398675
impact of acanthamoeba cysts on stress resistance of salmonella enterica serovar typhimurium, yersinia enterocolitica 4/o:3, listeria monocytogenes 1/2a, and escherichia coli o:26.the formation of robust resting cysts enables acanthamoeba to resist harsh environmental conditions. this study investigated to what extent these cysts are resistant to physical and chemical stresses as applied in food industry cleaning and disinfection procedures. moreover, it was assessed whether certain intracystic meat-borne bacterial pathogens are more stress resistant than free-living bacterial monocultures and if intracystic passage and subsequent association with trophozoites induces cro ...201728526786
uv-curable contact active benzophenone terminated quaternary ammonium antimicrobials for applications in polymer plastics and related devices.a series of uv active benzophenone ([c6h5coc6h4-o-(ch2)n-n+me2r][x-], 4: r = c12h25, n = 3, x- = br- , 5a-c: r = c18h37, n = 3, x- = cl-, br-, i-; 6a-c: r = c18h37, n = 4, x- = cl-, br-, i- ; 7a-c: r = c18h37, n = 6, x- = cl-, br-, i-) terminated c12 and c18 quaternary ammonium salts (qacs) were prepared by thermal or microwave driven menshutkin protocols of the appropriate benzophenone alkyl halide (1a-c, 2a-c, 3a-c) with the corresponding dodecyl- or octadecyl n,n-dimethylamine. all new compou ...201728777541
diversity of endophytic bacteria in a fern species dryopteris uniformis (makino) makino and evaluation of their antibacterial potential against five foodborne pathogenic bacteria.the fern plant dryopteris uniformis has traditionally been used in herbal medicine and possesses many biological activities. this study was conducted to explore the endophytic bacterial diversity associated with d. uniformis and evaluate their antibacterial potential against foodborne pathogenic bacteria (fpb). among 51 isolated endophytic bacteria (eb), 26 eb were selected based on their morphological characteristics and identified by 16s rrna gene analysis. the distribution of eb was diverse i ...201728418717
molecular characterization of gluten hydrolysing bacillus sp. and their efficacy and biotherapeutic potential as probiotics using caco-2 cell line.to isolate and characterize indigenous gluten hydrolysing bacteria from wheat sourdough and curd samples and further evaluation of their probiotic potentiality.201728637081
chemical constituents of helichrysum italicum (roth) g. don essential oil and their antimicrobial activity against gram-positive and gram-negative bacteria, filamentous fungi and candida albicans.the aerial parts of helichrysum italicum (roth) g. don were subjected to hydrodistillation to obtain essential oils which had been analyzed by gas chromatography and gas chromatography coupled with mass spectrometry and tested for antimicrobial activity against 12 bacteria, two yeasts and four fungi by agar diffusion method. the essential oil yielded 0.44% (v/w) and 67 compounds accounting for 99.24% of the oil were identified with a high content of oxygenated sesquiterpenes (61.42%). the most o ...201728725151
development and characterization of bioactive edible films from spider crab (maja crispata) chitosan incorporated with spirulina extract.active food packaging films based on crab chitosan and spirulina extract (se) were developed. the effects of the se incorporation at different levels on physical (color, opacity water vapor and oxygen permeability) and mechanical (tensile strength and elongation at break) properties of chitosan films were investigated. ftir was carried out to observe the potential modifications of the chitosan films when incorporated with se. the obtained results suggested that incorporation of se into chitosan ...201728705500
identification and growth optimization of a marine bacillus dk1-sa11 having potential of producing broad spectrum antimicrobial compounds.control of harmful bacteria in food, aquaculture, pharmaceuticals, agriculture, hospitals and recreation water pools are of great global concern. marine bacteria are an enormous source of bio-controlling agents. the aim of this study was to identify and optimize the growth conditions including effect of different biotic and abiotic factors on antimicrobial activity of strain dk1-sa11 isolated from qingdao bay of china yellow sea. microscopic characterization, api® 20e and 50 chb kit base carbohy ...201728653930
yvck, a protein required for cell wall integrity and optimal carbon source utilization, binds uridine diphosphate-sugars.in bacillus subtilis, listeria monocytogenes and in two mycobacteria, it was previously shown that yvck is a gene required for normal cell shape, for optimal carbon source utilization and for virulence of pathogenic bacteria. here we report that the b. subtilis protein yvck binds to uridine diphosphate-sugars like uridine diphosphate-glucose (udp-glc) and uridine diphosphate-n-acetylglucosamine (udp-glcnac) in vitro. using the crystal structure of bacillus halodurans yvck, we identified residues ...201728646159
antimicrobial effect of okcel® h-d prepared from oxidized cellulose.the antimicrobial effect of okcel® h-d, a topical, absorbable hemostatic textile prepared from oxidized cellulose, was tested. testing by dilution and diffusion methods was conducted on a spectrum of 27 select microorganisms, including also antibiotic-resistant strains. okcel® h-d showed inhibitory effects on nearly all tested bacteria. in testing using the dilution suspension method, the majority of bacteria showed decrease in cell density by 7-8 orders of magnitude after just 6 h of exposure. ...201728597345
investigation into the antimicrobial action and mechanism of a novel endogenous peptide β-casein 197 from human milk.a novel endogenous peptide cleaved from 197-213 aa of β-casein, named β-casein 197, was identified by tandem mass spectrometry. β-casein 197 constituted a significant proportion of the peptide content in preterm milk. this study investigated the antibacterial effects and mechanisms against common pathogenic bacteria. six bacterial strains were selected for this study: escherichia coli, staphylococcus aureus, yersinia enterocolitica, listeria monocytogenes, klebsiella pneumonia and bacillus subti ...201728591979
two complementary approaches to quantify variability in heat resistance of spores of bacillus subtilis.realistic prediction of microbial inactivation in food requires quantitative information on variability introduced by the microorganisms. bacillus subtilis forms heat resistant spores and in this study the impact of strain variability on spore heat resistance was quantified using 20 strains. in addition, experimental variability was quantified by using technical replicates per heat treatment experiment, and reproduction variability was quantified by using two biologically independent spore crops ...201728478320
development of an isothermal amplification-based assay for the rapid visual detection of salmonella bacteria.the efficient and timely detection of pathogens is a major concern worldwide. the aim of this study was to establish a rapid detection method for salmonella bacteria in food samples to facilitate timely treatment. widely used detection methods currently include culture-based methods and pcr-based methods. the former are time consuming, requiring 2 to 3 d, whereas the latter have higher accuracy but are typically complicated, requiring expertise and expensive instruments. in this study, a sensiti ...201728711269
a rapid salmonella detection method involving thermophilic helicase-dependent amplification and a lateral flow assay.salmonella is a major foodborne pathogen that is widespread in the environment and can cause serious human and animal disease. since conventional culture methods to detect salmonella are time-consuming and laborious, rapid and accurate techniques to detect this pathogen are critically important for food safety and diagnosing foodborne illness. in this study, we developed a rapid, simple and portable salmonella detection strategy that combines thermophilic helicase-dependent amplification (thda) ...201728526589
inactivation of viruses and bacteria on strawberries using a levulinic acid plus sodium dodecyl sulfate based sanitizer, taking sensorial and chemical food safety aspects into account.the efficacy of levulinic acid (lva) in combination with sodium dodecyl sulfate (sds) in removal of foodborne viruses, enteric bacterial pathogens and their surrogates on fresh strawberries was investigated. inoculated strawberries were treated with potable water, sodium hypochlorite solution (50ppm), 0.5% lva plus 0.5% sds solution, and 5% lva plus 2% sds solution respectively for 2min, followed by spray-rinsing with potable water. water washing removed at least 1.0-log of the tested viral and ...201728668727
emerging microbiota during cold storage and temperature abuse of ready-to-eat salad​.introduction: ready-to-eat (rte) leafy vegetables have a natural leaf microbiota that changes during different processing and handling steps from farm to fork. the objectives of this study were (i) to compare the microbiota of rte baby spinach and mixed-ingredient salad before and after seven days of storage at 8°c or 15°c; (ii) to explore associations between bacterial communities and the foodborne pathogens listeria monocytogenes, pathogenic yersinia enterocolitica, and pathogen model organism ...201728649305
slightly acidic electrolyzed water combined with chemical and physical treatments to decontaminate bacteria on fresh fruits.effect of sequential combination of slightly acidic electrolyzed water (saew) with chemical and physical treatments on bacterial decontamination on fruits was investigated in this study. effect of treatments on microbial and sensory quality was also analyzed after subsequent storage at 4 °c and room temperature (rt, 23 ± 0.15 °c). whole apple and tomato fruits were inoculated with cocktail strains of escherichia coli o157:h7 and listeria monocytogenes. uninoculated and inoculated fruits were was ...201728648298
inactivation of bacterial biofilms by visible light-activated unmodified zno nanorods.various zinc oxide (zno) nanostructures are widely used for photocatalytic antibacterial applications. since zno possess a wide bandgap, it is believed that only uv light may efficiently assist bacterial inactivation and diverse crystal lattice modifications should be applied in order to narrow the bandgap for efficient visible light absorption. in this work we show that even unmodified zno nanorods grown by aqueous chemical growth technique were found to possess intrinsic defects which can be a ...201728628486
inactivation of nonpathogenic escherichia coli, escherichia coli o157:h7, salmonella enterica typhimurium, and listeria monocytogenes in ice using a uvc light-emitting diode.ice, widely used in the food industry, is a potential cause of food poisoning resulting from microbial contamination. direct microbial inactivation of ice is necessary because microorganisms may have been present in the source water used to make it and/or may have been introduced due to poor hygiene during production or handling of the ice. nonthermal and nondestructive microbial inactivation technologies are needed to control microorganisms in ice. we evaluated the applicability of a uvc light- ...201728621585
sensitive detection of staphylococcus aureus with vancomycin-conjugated magnetic beads as enrichment carriers combined with flow cytometry.a novel sandwich strategy was designed to detect staphylococcus aureus. the strategy is based on an antibacterial agent that captures bacterial cells and a fluorescein-labeled antibody that acts as the signal-output probe. vancomycin (van), which exerts a strong antibacterial effect on gram-positive bacteria, was utilized as a molecular recognition agent to detect pathogenic bacteria. to effectively concentrate s. aureus, we used bovine serum albumin (bsa) as the amplification carrier to modify ...201728590745
bactericidal effect of 266 to 279nm wavelength uvc-leds for inactivation of gram positive and gram negative foodborne pathogenic bacteria and yeasts.recently, uvc-led technology has been validated as an alternative to irradiation with conventional mercury uv lamps. in this study, we sought to determine primary factors affecting reduction trends shown in several microorganisms. four major foodborne pathogens (escherichia coli o157:h7, salmonella spp. listeria monocytogenes, staphylococcus aureus) and spoilage yeasts (saccharomyces pastorianus, pichia membranaefaciens), important to the brewing industry, were inoculated onto selective and non- ...201728578053
evaluation of different solvents to extract antibacterial compounds from jalapeño peppers.chili peppers (capsicum spp.) may possess antibacterial properties and have potential to be used in foods as antimicrobial. the complete chili pepper extract should be evaluated to determine which compounds are responsible for the antimicrobial activity. extraction of compounds from the pepper is completed using a solvent. the type of solvent used for extraction influences which compounds are isolated, therefore the best extraction method needs to be determined. the purpose of this study was to ...201728572934
production and characterization of a new biodegradable fenugreek seed gum based active nanocomposite film reinforced with nanoclays.in the present work, fenugreek seed gum (fsg)/clay nanocomposite films were prepared with nanoclays (na(+) montmorillonite [mmt], halloysite [hnt] and nanomer(®) i.44 p [nm]) at different amounts (0, 2.5, 5.0 and 7.5g clay/100g fsg) by solution casting method and characterized. increasing amount of nanoclay significantly (p<0.05) improved oxygen barrier and thermal properties of the biodegradable films. agar diffusion tests revealed that fsg based nanocomposite films exhibited strong antimicrobi ...201728536016
investigation of optimum ohmic heating conditions for inactivation of escherichia coli o157:h7, salmonella enterica serovar typhimurium, and listeria monocytogenes in apple juice.control of foodborne pathogens is an important issue for the fruit juice industry and ohmic heating treatment has been considered as one of the promising antimicrobial interventions. however, to date, evaluation of the relationship between inactivation of foodborne pathogens and system performance efficiency based on differing soluble solids content of apple juice during ohmic heating treatment has not been well studied. this study aims to investigate effective voltage gradients of an ohmic heat ...201728525985
development of a gold nanoparticle-based universal oligonucleotide microarray for multiplex and low-cost detection of foodborne pathogens.bacterial foodborne diseases remain major threats to food safety and public health, especially in developing countries. in this study a novel assay, combining gold nanoparticle (gnp)-based multiplex oligonucleotide ligation-pcr and universal oligonucleotide microarray technology, was developed for inexpensive, specific, sensitive, and multiplex detection of eight common foodborne pathogens, including shigella spp., campylobacter jejuni, bacillus cereus, escherichia coli o157:h7, listeria monocyt ...201728505584
potential of cinnamon oil emulsions as alternative washing solutions of carrots.the objective of this study was to evaluate the potential of cinnamon oil emulsions as alternative washing solutions to improve the microbial safety of carrots. whey protein concentrate (wpc), gum arabic (ga), lecithin, and their combinations were used to prepare cinnamon oil emulsions. the emulsions were characterized for their hydrodynamic diameter (dh) during 7 days of storage and their antimicrobial activity against cocktails of salmonella enterica , escherichia coli o157:h7, and listeria mo ...201728467186
getting "inside" type i ifns: type i ifns in intracellular bacterial infections.type i interferons represent a unique and complex group of cytokines, serving many purposes during innate and adaptive immunity. discovered in the context of viral infections, type i ifns are now known to have myriad effects in infectious and autoimmune disease settings. type i ifn signaling during bacterial infections is dependent on many factors including whether the infecting bacterium is intracellular or extracellular, as different signaling pathways are activated. as such, the repercussions ...201728529959
irrigation water sources and time intervals as variables on the presence of campylobacter spp. and listeria monocytogenes on romaine lettuce grown in muck soil.irrigation water has been identified as a possible source of vegetable contamination by foodborne pathogens. risk management for pathogens such as campylobacter spp. and listeria monocytogenes in fields can be influenced by the source of the irrigation water and the time interval between last irrigation and harvest. plots of romaine lettuce were irrigated with manure-contaminated water or aerated pond water 21, 7, or 3 days prior to harvesting, and water and muck soil samples were collected at e ...201728604176
postchill antimicrobial treatments to control salmonella, listeria, and campylobacter contamination on chicken skin used in ground chicken.ground poultry products are frequently contaminated with foodborne pathogens. with the potential for increased regulatory scrutiny, it is important to use sufficient intervention strategies to control pathogen levels effectively. a large proportion of the bacteria introduced to ground chicken are likely to come from broiler skin, which is added to achieve target fat content and maintain product texture and taste. in this research, antimicrobials, including 50 ppm of chlorine and 1,200 ppm of per ...201728414258
rnaseq reveals complex response of campylobacter jejuni to ovine bile and in vivo gallbladder environment.colonization of the gallbladder by enteric pathogens such as salmonella typhi, listeria monocytogenes, and campylobacter jejuni is thought to play a key role in transmission and persistence of these important zoonotic agents; however, little is known about the molecular mechanisms that allow for bacterial survival within this harsh environment. recently, a highly virulent c. jejuni sheep abortion (sa) clone represented by the clinical isolate ia3902 has emerged as the dominant cause for sheep ab ...201728611744
protein kinase c-delta (pkcδ), a marker of inflammation and tuberculosis disease progression in humans, is important for optimal macrophage killing effector functions and survival in mice.we previously demonstrated that protein kinase c-δ (pkcδ) is critical for immunity against listeria monocytogenes, leishmania major, and candida albicans infection in mice. however, the functional relevance of pkcδ during mycobacterium tuberculosis (mtb) infection is unknown. pkcδ was significantly upregulated in whole blood of patients with active tuberculosis (tb) disease. lung proteomics further revealed that pkcδ was highly abundant in the necrotic and cavitory regions of tb granulomas in mu ...201728832027
purification of leucocin a for use on wieners to inhibit listeria monocytogenes in the presence of spoilage organisms.the aims of this study were to improve the method for purification of leucocin a to increase yield of peptide and to evaluate the efficacy of leucocin a and an analogue of leucocin a (leucocin n17l) to inhibit the growth of listeria monocytogenes on wieners in the presence of spoilage organisms. leucocin a was produced by leuconostoc gelidum ual187 and purified with a five-fold increase in yield; leucocin n17l was synthesized replacing asparagine at residue 17 with leucine. five strains of l. mo ...201728570918
tpl2 promotes innate cell recruitment and effector t cell differentiation to limit citrobacter rodentium burden and dissemination.tumor progression locus 2 (tpl2) is a serine-threonine kinase that regulates th1 differentiation, secretion of the inflammatory cytokine ifnγ, and host defense against the intracellular pathogens toxoplasma gondii, listeria monocytogenes, and mycobacterium tuberculosis however, there is relatively little known about the contribution of tpl2 to th17 differentiation and immune cell function during infection with an extracellular pathogen. the goal of this study was to determine whether tpl2 influe ...201728760932
selection of surrogate bacteria for use in food safety challenge studies: a review.nonpathogenic surrogate bacteria are prevalently used in a variety of food challenge studies in place of foodborne pathogens such as listeria monocytogenes, salmonella, escherichia coli o157:h7, and clostridium botulinum because of safety and sanitary concerns. surrogate bacteria should have growth characteristics and/or inactivation kinetics similar to those of target pathogens under given conditions in challenge studies. it is of great importance to carefully select and validate potential surr ...201728805457
vaginal self-sampling as a diagnosis tool in low-income countries and potential applications for exploring the infectious causes of miscarriage.gynecological health is a challenge in low-income countries. personal opposition to perineal examination has been overcome by the use of vaginal self-sampling. here, we review the use of this procedure notably in low-income countries and the main infectious causes of miscarriage. vaginal self-sampling was mainly used for human papillomavirus detection but also to detect microorganisms causing sexually transmitted infections or bacterial vaginosis. 58 studies have been performed in low-resource c ...201728604063
exploitation of spr to investigate the importance of glycan chains in the interaction between lactoferrin and bacteria.bovine lactoferrin (lf) has been shown to prevent adhesion to and invasion of mammalian cell lines by pathogenic bacteria, with evidence for direct bacterial binding by the milk glycoprotein. however, the glycosylation pattern of lf changes over the lactation cycle. in this study, we aim to investigate the effect that this variation has on the milk glycoprotein's ability to interact with pathogens. surface plasmon resonance technology was employed to compare the binding of lf from colostrum (ear ...201728653977
the epidemiology, management, and outcomes of bacterial meningitis in infants.the pathogens that cause bacterial meningitis in infants and their antimicrobial susceptibilities may have changed in this era of increasing antimicrobial resistance, use of conjugated vaccines, and maternal antibiotic prophylaxis for group b streptococcus (gbs). the objective was to determine the optimal empirical antibiotics for bacterial meningitis in early infancy.201728600447
clec5a is a critical receptor in innate immunity against listeria infection.the c-type lectin member 5a (clec5a) is a pattern recognition receptor for members of the flavivirus family and has critical functions in response to dengue virus and japanese encephalitis virus. here we show that clec5a is involved in neutrophil extracellular trap formation and the production of reactive oxygen species and proinflammatory cytokines in response to listeria monocytogenes. inoculation of clec5a (-/-) mice with l. monocytogenes causes rapid bacterial spreading, increased bacterial ...201728824166
characterization of enterococcus durans 152 bacteriocins and their inhibition of listeria monocytogenes in ham.listeria monocytogenes is a nonfastidious, widely occurring foodborne pathogen that is a major challenge to the food industry. enterococcus durans 152, a confirmed l. monocytogenes-control microorganism, was isolated from floor drain samples from a food processing facility. in this study, the two bacteriocins produced by e. durans 152 were characterized and identified as dur 152a (an enterocin l50a derivative with two amino acid substitutions of i→m) and enterocin l50b. the bacteriocins were the ...201728800831
characterization and application of antilisterial enterocins on model fresh cheese.enterococcus faecalis strains isolated from an artisanal cheese were selected based on enterocin production against listeria monocytogenes. the strains formed biofilms and presented high hydrophobic character and good autoaggregation and coaggregation capacity with l. monocytogenes. strains l3a21m3 and l3b1k3 presented high survival under gastrointestinal conditions, were able to adhere to human intestinal cells (caco-2 and ht-29), and blocked the adhesion and invasion of l. monocytogenes. the a ...201728703625
signal biosynthesis inhibition with ambuic acid as a strategy to target antibiotic-resistant infections.there has been major interest by the scientific community in antivirulence approaches against bacterial infections. however, partly due to a lack of viable lead compounds, antivirulence therapeutics have yet to reach the clinic. here we investigate the development of an antivirulence lead targeting quorum sensing signal biosynthesis, a process that is conserved in gram-positive bacterial pathogens. some preliminary studies suggest that the small molecule ambuic acid is a signal biosynthesis inhi ...201728607020
testing commercial biopreservative against spoilage microorganisms in map packed ricotta fresca cheese.ricotta fresca cheese is susceptible to secondary contamination and is able to support the growth of pathogens or spoilage psychotrophic bacteria during storage. the aim of the present study was to evaluate which among three commercial biopreservatives was suitable to be used to control the growth of spoilage microorganisms in sheep's milk map ricotta fresca cheese. 144 ricotta fresca cheese samples were inoculated either with the bioprotective culture lyofast fpr 2 (including enterococcus faeci ...201728576375
bacteriocin-producing enterococcus faecium lcw 44: a high potential probiotic candidate from raw camel milk.bacterial isolates from raw camel milk were screened for antibacterial activity using the agar diffusion assay. ten isolates selected for their inhibition of gram-positive bacteria were identified by 16s sequencing as enterococcus faecium or durans. an isolate named e. faecium lcw 44 exhibited the broadest antibacterial spectrum with an inhibitory activity against several gram-positive strains belonging to the genera clostridium, listeria, staphylococcus, and lactobacillus. e. faecium lcw 44 was ...201728572793
application of nanocompostie chitosan and carboxymethyl cellulose films containing natural preservative compounds in minced camel's meat.in the present study, novel films based on nanomontmorillonite-chitosan (mmt-ch) and nanomontmorillonite-carboxymethyl cellulose (mmt-cmc) incorporated with different concentrations of ziziphora clinopodioides essential oil (zeo; 0.5, 1 and 2%) alone and in combination with ficus carica extract (fch; 1%) were investigated as active packaging materials for minced camel's meat to increase the shelf life (microbial, chemical and sensory properties) and inhibit the growth of listeria monocytogenes a ...201728847602
impact of the reusing of food manufacturing wastewater for irrigation in a closed system on the microbiological quality of the food crops.in order to evaluate if the reuse of food industry treated wastewater is compatible for irrigation of food crops, without increased health risk, in the present study a cropping system, in which ground water and treated wastewater were used for irrigation of tomato and broccoli, during consecutive crop seasons was monitored. water, crop environment and final products were monitored for microbial indicators and pathogenic bacteria, by conventional and molecular methods. the microbial quality of th ...201728843124
in vitro characterization of lactobacillus strains isolated from fruit processing by-products as potential probiotics.nine wild lactobacillus strains, namely lactobacillus plantarum 53, lactobacillus fermentum 56, l. fermentum 60, lactobacillus paracasei 106, l. fermentum 250, l. fermentum 263, l. fermentum 139, l. fermentum 141, and l. fermentum 296, isolated from fruit processing by-products were evaluated in vitro for a series of safety, physiological functionality, and technological properties that could enable their use as probiotics. considering the safety aspects, the resistance to antibiotics varied amo ...201728836171
simultaneous detection of escherichia coli o157:h7, salmonella enteritidis, and listeria monocytogenes at a very low level using simultaneous enrichment broth and multichannel spr biosensor.detection of foodborne pathogens at very low levels is still a challenge. a custom-built multichannel surface plasmon resonance (spr) biosensor and simultaneous enrichment broth (seb) were used to develop a simultaneous detection method for 3 important foodborne pathogens, escherichia coli o157:h7 (o157:h7), salmonella enteritidis, and listeria monocytogenes, at a very low level. these 3 foodborne pathogens at a very low level (14, 6, and 28 cfu/25 g (ml) for o157:h7, s. enteritidis, and l. mono ...201728833106
synthesis and antimicrobial studies of new antibacterial azo-compounds active against staphylococcus aureus and listeria monocytogenes.some novel (phenyl-diazenyl)phenols (4a-m) were designed and synthesized to be evaluated for their antibacterial activity. starting from an active previously-synthesized azobenzene chosen as lead compound, we introduced some modifications and optimization of the structure, in order to improve solubility and drug conveyance. structures of all newly-synthesized compounds were confirmed by ¹h nuclear magnetic resonance (nmr), mass spectrometry, and uv-vis spectroscopy. antibacterial activity of the ...201728825625
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