Publications

TitleAbstractYear(sorted descending)
Filter
PMID
Filter
development and validation of a stochastic model for potential growth of listeria monocytogenes in naturally contaminated lightly preserved seafood.a new stochastic model for the simultaneous growth of listeria monocytogenes and lactic acid bacteria (lab) was developed and validated on data from naturally contaminated samples of cold-smoked greenland halibut (csgh) and cold-smoked salmon (css). during industrial processing these samples were added acetic and/or lactic acids. the stochastic model was developed from an existing deterministic model including the effect of 12 environmental parameters and microbial interaction (o. mejlholm and p ...201525500393
modeling transfer of escherichia coli o157:h7 and listeria monocytogenes during preparation of fresh-cut salads: impact of cutting and shredding practices.cutting and shredding of leafy vegetables increases the risk of cross contamination in household settings. the distribution of escherichia coli o157:h7 and listeria monocytogenes transfer rates (tr) between cutting knives and lettuce leaves was investigated and a semi-mechanistic model describing the bacterial transfer during consecutive cuts of leafy vegetables was developed. for both pathogens the distribution of log10trs from lettuce to knife was towards low values. conversely log10trs from k ...201525500391
investigating boundaries of survival, growth and expression of genes associated with stress and virulence of listeria monocytogenes in response to acid and osmotic stress.the objective of this study was to correlate the relative transcription of listeria monocytogenes (strains c5, 6179) stress- (gad2, sigb) and virulence- (prfa) associated genes following habituation at twenty-five ph (4.8, 5.0, 5.2, 5.5, 6.4) and nacl (2, 4, 6, 8, 10% w/v) combinations at 7 °c, with the survival against subsequent exposure to severe acid stress (ph 2.0 at 37 °c). our findings pointed out the inter-strain variation governing growth inhibiting conditions (ph ≤5.0 and nacl ≥6%), wh ...201525500389
comparison of individual-based modeling and population approaches for prediction of foodborne pathogens growth.individual-based modeling (ibm) approach combined with the microenvironment modeling of vacuum-packed cold-smoked salmon was more effective to describe the variability of the growth of a few listeria monocytogenes cells contaminating irradiated salmon slices than the traditional population models. the ibm approach was particularly relevant to predict the absence of growth in 25% (5 among 20) of artificially contaminated cold-smoked salmon samples stored at 8 °c. these results confirmed similar o ...201525500386
preparation, characterization, and antimicrobial activity of chitin nanofibrils reinforced carrageenan nanocomposite films.present study illustrates the preparation of chitin nanofibrils (cnf) reinforced carrageenan nanocomposite films by the solution-casting technique. cnf was prepared by acid hydrolysis of chitin, followed by high speed homogenization and sonication. ftir result demonstrated that the chemical structure of chitin had not changed after acid hydrolysis. however, the crystalinity of cnf was found to be higher than chitin. the crystallite size of chitin and cnf was 4.73 and 6.27 nm, respectively. the c ...201525498660
essential oils from herbs against foodborne pathogens in chicken sausage.consumption of chicken meat and its products, especially sausage, have increased in recent years. however, this product is susceptible to microbial contamination during manufacturing, which compromises its shelf life. the flavoring and preservative activities of essential oils (eo) have been recognized and the application of these antimicrobial agents as natural active compounds in food preservation has shown promise. the aim of this study was to evaluate the effect of ocimum basilicum and origa ...201525492235
synergistic effect of gamma (γ)-irradiation and microencapsulated antimicrobials against listeria monocytogenes on ready-to-eat (rte) meat.oregano essential oil (origanum compactum; 250 μg/ml), cinnamon essential oil (cinnamomum cassia; 250 μg/ml) and nisin (16 μg/ml) were used alone or in combination to evaluate their efficiency to inhibit the growth of listeria monocytogenes on rte ham. microencapsulation of the antimicrobial formulations was done to verify the potential effect of the polymer to protect the antimicrobial efficiency during storage. combined treatments of antimicrobial formulation with γ-irradiation were done to ve ...201525475322
role of sigb and osmolytes in desiccation survival of listeria monocytogenes in simulated food soils on the surface of food grade stainless steel.this research aimed to determine whether the sigb (σ(b)) regulon and osmolytes impact the survival of the foodborne pathogen, listeria monocytogenes, during desiccation in simulated food soils with varying salt and nutrient contents on food grade stainless steel (ss) surfaces. l. monocytogenes 568 (lm568, serotype 1/2a), its isogenic sigb mutant (δsigb) and the back-complemented δsigb were desiccated in bhi, tsb with 1% glucose (tsb-glu), peptone physiological saline (pps) and minimal media (mm) ...201525475314
differential gene expression profiling of listeria monocytogenes in cacciatore and felino salami to reveal potential stress resistance biomarkers.the current study reports a) the in situ transcriptional profiles of listeria monocytogenes in response to fermented sausage stress and b) an approach in which in situ rt-qpcr data have been combined with advanced statistical techniques to discover potential stress resistance or cell viability biomarkers. gene expression profiling of the pathogen has been investigated using rt-qpcr to understand how l. monocytogenes responds to the conditions encountered during the fermentation and ripening of s ...201525475310
environmental and biological factors influencing the uv-c resistance of listeria monocytogenes.in this investigation, the effect of microbiological factors (strain, growth phase, exposition to sublethal stresses, and photorepair ability), treatment medium characteristics (ph, water activity, and absorption coefficient), and processing parameters (dose and temperature) on the uv resistance of listeria monocytogenes was studied. the dose to inactivate 99.99% of the initial population of the five strains tested ranged from 21.84 j/ml (stcc 5672) to 14.66 j/ml (stcc 4031). the uv inactivation ...201525475293
effect of quantity of food residues on resistance to desiccation of food-related pathogens adhered to a stainless steel surface.in order to study the effect of food residues on the survival of food-borne pathogens, salmonella typhimurium, staphylococcus aureus, and listeria monocytogenes were subjected to drying conditions in the presence of small amounts of food such as carrot juice, aqueous solution of nori, milk, and soy-milk. after drying for 2 h at room temperature in the absence of food residue, cell counts of s. typhimurium, s. aureus, and l. monocytogenes decreased from 8 to 3, 6, and 5 log cfu/dish, respectively ...201525475291
effects of osmotic pressure, acid, or cold stresses on antibiotic susceptibility of listeria monocytogenes.prevalence of antibiotic resistance of listeria monocytogenes isolated from a variety of foods has increased in many countries. l. monocytogenes has many physiological adaptations that enable survival under a wide range of environmental stresses. the objective of this study was to evaluate effects of osmotic (2, 4, 6, 12% nac), ph (6, 5.5, 5.0) and cold (4 °c) stresses on susceptibility of three isolates of l. monocytogenes towards different antibiotics. the minimal inhibitory concentrations (mi ...201525475279
flexible thin-layer dielectric barrier discharge plasma treatment of pork butt and beef loin: effects on pathogen inactivation and meat-quality attributes.the effects of a flexible thin-layer dielectric barrier discharge (dbd) plasma system using a sealed package on microbial inactivation and quality attributes of fresh pork and beef were tested. following a 10-min treatment, the microbial-load reductions of listeria monocytogenes, escherichia coli o157:h7, and salmonella typhimurium were 2.04, 2.54, and 2.68 log cfu/g in pork-butt samples and 1.90, 2.57, and 2.58 log cfu/g in beef-loin samples, respectively. colorimetric analysis showed that dbd- ...201525475266
pregnancy-associated listeriosis in england and wales.listeriosis is a rare but severe foodborne disease with low morbidity and high case-fatality rates. pregnant women, unborn and newborn babies are among the high-risk groups for listeriosis. we examined listeriosis cases reported to the enhanced surveillance system in england and wales from 1990 to 2010 to identify risk factors influencing outcome. cases were defined as pregnancy-associated if listeria monocytogenes was isolated from a pregnant woman or newborn infants aged <28 days. of the 3088 ...201524650375
technologies and mechanisms for safety control of ready-to-eat muscle foods: an updated review.ready-to-eat (rte) muscle foods refer to a general category of meat and poultry products that are fully cooked and consumable without reheating. these products, including whole and sliced pork, beef, turkey, chicken, and variety of meats, in the forms of ham, roast, rolls, sausage, and frankfurter, are widely available in the delicatessen section of retail stores or various food service outlets. however, difficulties in avoidance of contamination by foodborne pathogens, notably listeria monocyto ...201524754253
occurrence, antibiotic resistance and molecular characterization of listeria monocytogenes in the beef chain in the republic of ireland.this study investigated the occurrence, concentration and key characteristics of listeria monocytogenes in beef chain samples (n=1100) over a 2-year period (july 2007-june 2009). listeria monocytogenes was isolated from bovine hides (27%), pre-chill carcasses (14%) and ground beef (29%), but not from ready-to-eat (rte) beef. the concentration of the pathogen in the majority (95%) of contaminated samples was low and detected by enrichment only. the highest concentrations recovered (100-200 cfu/g) ...201524506835
identification, characterization, immobilization of a novel type hydrolase (lmh) from listeria monocytogenes.a novel type of hydrolase (lmh) from listeria monocytogenes was identified, characterized, and immobilized for biotechnological applications. primary sequence analysis indicated that lmh had a catalytic triad (ser(91)-asp(192)-his(222)) with a molecular weight of 27.8 kda. homologs of this enzyme are produced by many gram-positive bacteria including bacillus, staphylococcus, and enterococcus. biochemical properties of lmh were investigated by performing mass spectrometry, dynamic light scatterin ...201525128099
urban prevalence of listeria spp. and listeria monocytogenes in public lavatories and on shoe soles of facility patrons in the european capital city vienna.the aim of this study was to determine the prevalence of listeria spp. and listeria monocytogenes (l. monocytogenes) in urban public lavatories and on shoe soles of facility patrons in a european capital city. more than 91% of all municipal public lavatories in vienna close to public hubs were included in this study. overall, 373 swab samples of public lavatories and shoes of facility patrons were enriched, according to iso 11290-1. listeria monocytogenes isolates were subtyped using pulsed-fiel ...201524751465
antimicrobial susceptibility of listeria monocytogenes isolates from human cases in northern italy, 2008-2010: mic determination according to eucast broth microdilution method.susceptibility of 96 listeria monocytogenes human isolates collected in northern italy between 2008 and 2010, to 15 antimicrobials, was investigated. minimum inhibitory concentration (mic) was evaluated by means of the standardized broth microdilution method, according to the european committee on antimicrobial susceptibility testing (eucast) international guidelines. all l. monocytogenes human isolates were susceptible to penicillin g (mic(90)≤0·06 μg/ml), meropenem (mic(90)≤0·06 μg/ml), and er ...201524720267
listeria monocytogenes infection in a sugar glider (petaurus breviceps) - new mexico, 2011.listeria monocytogenes is a gram-positive, facultative anaerobic, rod-shaped bacterium that can infect and cause disease in many species. in this case report, we describe a case of l. monocytogenes infection causing sepsis in a sugar glider (petaurus breviceps). the sugar glider consumed a varied diet consisting of human food items, including cantaloupe. a nationwide outbreak of l. monocytogenes foodborne illness associated with cantaloupes occurred simultaneously with this incident case. in thi ...201524815369
enhanced inactivation of food-borne pathogens in ready-to-eat sliced ham by near-infrared heating combined with uv-c irradiation and mechanism of the synergistic bactericidal action.the objective of the study described in this article was, first, to investigate the effect of the simultaneous application of near-infrared (nir) heating and uv irradiation on inactivation of escherichia coli o157:h7, salmonella enterica serovar typhimurium, and listeria monocytogenes in ready-to-eat (rte) sliced ham and as well as its effect on product quality and, second, to elucidate the underlying mechanisms of the synergistic bactericidal action of nir heating and uv irradiation. with the i ...201525107964
stability, compatibility and microbiological activity studies of meropenem-clavulanate potassium.meropenem (mem) and clavulanate potassium have been reported to demonstrate highly effective activity against mycobacterium tuberculosis. there have been no reports on research into the complex of these chemotherapeutics concerning their mutually dependent stability or microbiological action on other microorganisms. stability and compatibility studies of mem/clavulanate potassium were conducted by using an hplc-dad method. the antibacterial activity of mem/clavulanate potassium was tested in vit ...201525074659
definition of a standard protocol to determine the growth potential of listeria monotgenes and yersinia enterocolitica in pork sausage produced in abruzzo region, italy.pork meat products consumed raw or after a short period of fermentation can be considered at risk for food safety. sausages (fresh sausage made from pork meat) are produced in several italian regions, with variation in ingredients. in some italian regions, including abruzzo, these products are frequently consumed raw or undercooked, after a variable period of fermentation. the european community food regulation promotes the use of challenge tests to determine safety levels. this study is aimed t ...201527800415
listeria monocytogenes dose response revisited--incorporating adjustments for variability in strain virulence and host susceptibility.evaluations of listeria monocytogenes dose-response relationships are crucially important for risk assessment and risk management, but are complicated by considerable variability across population subgroups and l. monocytogenes strains. despite difficulties associated with the collection of adequate data from outbreak investigations or sporadic cases, the limitations of currently available animal models, and the inability to conduct human volunteer studies, some of the available data now allow r ...201524975545
[effect of volatile metabolites from germinating seeds on the reproduction of the bacteria listeria monocytogenes and yersinia pseudotuberculosis].the biological activity of volatile metabolites of germinating seeds of cabbage (brassica oleacia), carrot (daukus carota), salad (lactuca sativa), and corn (zea mays l.) against listeria monocytogenes and yersinia pseudotuberculosis was studied. it was shown that volatile metabolites are transfer factors and can be the sole carbon and energy source for these bacteria. methanol is the main substance affecting their growth and reproduction.201522834302
exploring specific primers targeted against different genes for a multiplex pcr for detection of listeria monocytogenes.the efficacy of six different sets of primers targeted against 16s rrna and virulence genes such as 'iap', 'hly' and 'prf' was evaluated in separate pcr assays. the primer pairs targeted against 16s rrna resulted into amplification of 1.2 kb pcr product. however, sets of primers targeted against different regions of 'iap' produced 371 and 660 bp pcr products, respectively. the primer pair targeted against 'prf' gene could produce 508 bp product. three primer pairs targeted against different regi ...201528324291
development and optimization of an egfp-based reporter for measuring the general stress response in listeria monocytogenes.a characteristic of the food-borne pathogen listeria monocytogenes is its tolerance to the harsh conditions found both in minimally processed foods and the human gastrointestinal tract. this trait is partly under the control of the alternative sigma factor sigma b (σ(b)). to study the mechanisms that trigger the activation of σ(b) , and hence the development of stress tolerance, we have developed a fluorescent reporter fusion that allows the real-time activity of σ(b) to be monitored. the report ...201522539028
relating physicochemical and microbiological safety indicators during processing of linguiça, a portuguese traditional dry-fermented sausage.linguiça is a portuguese traditional fermented sausage whose microbiological quality and safety can be highly variable. in order to elucidate risk factors and the particularities of the manufacturing technology that explain the between-batch variability in total viable counts (tvc), enterobacteriaceae, staphylococcus aureus and listeria monocytogenes in the product; microbiological and physicochemical characterisation of linguiça at five stages of production (i.e., raw pork meat, mixed with ingr ...201528433317
the challenge of challenge testing to monitor listeria monocytogenes growth on ready-to-eat foods in europe by following the european commission (2014) technical guidance document.european regulation (ec) no. 2073/2005 lays down the microbiological criteria for certain microorganisms in foods and the implementing rules to be complied with by food business operators (fbos) in europe when implementing general and specific hygiene measures. in relation to listeria monocytogenes, this regulation covers primarily ready-to-eat (rte) food products, and requires different microbiological criteria depending on the ability of the food product to support growth of l. monocytogenes. ...201528454952
modeling the protective effect of aw and fat content on the high pressure resistance of listeria monocytogenes in dry-cured ham.high pressure processing (hpp) is a promising food preservation technology as an alternative to thermal processing for microbial inactivation. the technological parameters, the type of microorganism, and the food composition can greatly affect the microbicidal potential of hpp against spoilage and pathogenic microorganisms. presently, the number of available models quantifying the influence of food characteristics on the pathogen inactivation is scarce. the aim of this study was to model the ina ...201528454947
bacterial attachment and biofilm formation on surfaces are reduced by small-diameter nanoscale pores: how small is small enough?prevention of biofilm formation by bacteria is of critical importance to areas that directly affect human health and life including medicine, dentistry, food processing and water treatment. this work showcases an effective and affordable solution for reducing attachment and biofilm formation by several pathogenic bacteria commonly associated with foodborne illnesses and medical infections.201528721236
sulfadiazine-chitosan conjugates and their polyelectrolyte complexes with hyaluronate destined to the management of burn wounds.in the present study polyelectrolyte complexes (pecs) based on new sulfadiazine-chitosan conjugates with sodium hyaluronate have been developed with potential use in treatment of burn wounds. the pecs were chemically characterized using fourier transform-infrared spectroscopy, scanning electon microscopy and near infrared chemical imaging technique. the swelling behavior and in vitro sulfadiazine release were also investigated. the antimicrobial activity was evaluated towards three bacterial str ...201528787940
molecular characterization of silver-stearate nanoparticles (agstnps): a hydrophobic and antimicrobial material against foodborne pathogens.in this study, silver-stearate nanoparticles (agstnps) have been produced from silver nitrate solutions by replacing the nitrate by stearate ions and then reducing by thermal treatment. agstnps were characterized by particle size, zeta-potential, atr-ftir, contact angle and sem (scanning electron microscopy) analyses. the mean particle size and zeta potential of agstnps were determined to be 69.22±7.30nm and +8.02±0.88mv. atr-ftir analysis showed characteristic ir bands of stearate, revealing th ...201528455024
capability of exopolysaccharide-producing lactobacillus paraplantarum bgcg11 and its non-producing isogenic strain nb1, to counteract the effect of enteropathogens upon the epithelial cell line ht29-mtx.the putative protective role of the exopolysaccharide (eps)-producing lactobacillus paraplantarum bgcg11, and its non-eps-producing isogenic strain nb1, was tested upon ht29-mtx monolayers challenged with seven opportunistic pathogens. the probiotic strain lactobacillus rhamnosus lmg18243 (gg) was used as a reference bacterium. tested lactobacilli were able to efficiently reduce the attachment to ht29-mtx of most pathogens. lb. paraplantarum nb1 and lb. rhamnosus gg were more efficient reducing ...201528411984
[measuring the control and decrease in prevalence of listeria monocytogenes species in foods of animal origin].a large distributed bacterium, listeria monocytogenes has been isolated from water and fresh vegetables, raw meat and processed meat (all types), and raw, salted and smoked fish. l. monocytogenes grows at low oxygen concentrations and at low temperatures, surviving for a long time in the environment, in the processing plant, as well as on the equipment, instruments and during storage at the refrigeration temperature. l. monocytogenes causes invasive listeriosis, often affecting immunocompromised ...201423745223
rapid detection of listeria monocytogenes in raw milk with loop-mediated isothermal amplification and chemosensor.loop-mediated isothermal amplification (lamp) allows a rapid amplification of nucleic acids under isothermal conditions. it can be combined with a rhodamine-based dual chemosensor for much more efficient, field-friendly detection of listeria monocytogenes. in this report, lamp was performed at 63 °c for 10 min, followed by a rapid reaction of dna amplification and the byproduct, pyrophosphate ion, with a rhodamine-based dual chemosensor and cu(2+) is visualized as a disappearance of red color. t ...201422416713
the central role of arginine catabolism in t-cell dysfunction and increased susceptibility to infection after physical injury.to explore the hypothesis that decreased arginine availability by myeloid-derived suppressor cells (mdscs) is a cause of t-cell dysfunction after physical injury (pi).201423470573
diagnostic exercise: suppurative rhombencephalitis and meningitis in a goat.a 1-year-old female boer goat was presented for necropsy following spontaneous death and history of acute recumbency, nystagmus, and sialorrhea. a swollen area was grossly observed in the brainstem at the level of the pons. on cut surface, the right cerebellar peduncles were expanded by a focal, pale, poorly demarcated, slightly depressed, and soft area of malacia. microscopically, this area contained diffuse edema and necrosis, with microabscesses, neuronal necrosis, neuronophagia, axonal spher ...201423576239
il-18 provided in dying bacterial-infected macrophages induces ifn-γ production in functional t-cell hybridoma b6ho3 through cell conjugates.we have previously reported that the co-culture of functional t-cell hybridoma b6ho3 with dying j774 macrophage cells infected with listeria monocytogenes (lm) results in the production of ifn-γ by b6ho3 cells. here, we explore the mechanism underlying this phenomenon. we found that ifn-γ production was dependent on il-18, but that the dying lm-infected macrophages produced no more than 100 pg/ml of il-18, much less than the amount of il-18 required for stimulating b6ho3 cells to produce ifn-γ. ...201423723378
seca2 is not required for secretion of the surface autolysin ispc in listeria monocytogenes serotype 4b.listeria monocytogenes is one of several gram-positive bacteria known to contain an auxiliary atpase (seca2) involved in the sec secretion of a subset of proteins important to bacterial pathogenesis, including autolysins. it is not known if ispc, a novel surface-associated autolysin essential for full virulence of l. monocytogenes serotype 4b, is seca2-dependent for secretion. by creating a seca2 gene deletion (δseca2) mutant from the wild type (wt) l. monocytogenes serotype 4b strain, in combin ...201423712923
role of the listeria monocytogenes 2-cys peroxiredoxin homologue in protection against oxidative and nitrosative stress and in virulence.peroxiredoxins contribute to protection of some bacteria against reactive oxygen intermediates (rois) and reactive nitrogen intermediates (rnis). listeria monocytogenes, a facultative intracellular bacterial pathogen, interacts with rois and rnis during infection. in this study, we investigated the involvement of the 2-cys peroxiredoxin (prx) homologue in l. monocytogenes in the protection against rois and rnis and in virulence through the construction of an in-frame prx deletion mutant. the δpr ...201423929591
risk-based approach for microbiological food safety management in the dairy industry: the case of listeria monocytogenes in soft cheese made from pasteurized milk.according to codex alimentarius commission recommendations, management options applied at the process production level should be based on good hygiene practices, haccp system, and new risk management metrics such as the food safety objective. to follow this last recommendation, the use of quantitative microbiological risk assessment is an appealing approach to link new risk-based metrics to management options that may be applied by food operators. through a specific case study, listeria monocyto ...201423777564
effects of growth phase and temperature on σb activity within a listeria monocytogenes population: evidence for rsbv-independent activation of σb at refrigeration temperatures.the alternative sigma factor σb of listeria monocytogenes is responsible for regulating the transcription of many of the genes necessary for adaptation to both food-related stresses and to conditions found within the gastrointestinal tract of the host. the present study sought to investigate the influence of growth phase and temperature on the activation of σb within populations of l. monocytogenes egd-e wild-type, δsigb, and δrsbv throughout growth at both 4°c and 37°c, using a reporter fusion ...201424734238
rhombencephalitis due to listeria monocytogenes: a case study. 201423260449
the surface protein lmo1941 with lysm domain influences cell wall structure and susceptibility of listeria monocytogenes to cephalosporins.listeria monocytogenes is a gram-positive bacterium causing rare but dangerous cases of disease in humans and animals. the β-lactams penicillin g and ampicillin are the antibiotics of choice in the treatment of listeriosis. recently, lmo1941, encoding a surface protein of l. monocytogenes with unknown function, was identified as a gene transcriptionally upregulated under penicillin g pressure. in this study, the effect of lmo1941 knockout on the susceptibility of l. monocytogenes to β-lactams wa ...201424974853
visual and sensitive detection of viable pathogenic bacteria by sensing of rna markers in gold nanoparticles based paper platform.food-borne pathogens have been recognized as a major cause of human infections worldwide. their identification needs to be simpler, cheaper and more reliable than the traditional methods. here, we constructed a low-cost paper platform for viable pathogenic bacteria detection with the naked eye. in this study, an effective isothermal amplification method was used to amplify the hlya mrna gene, a specific rna marker in listeria monocytogenes. the amplification products were applied to the paper-ba ...201424973541
pregnancy-associated listeriosis: clinical characteristics and geospatial analysis of a 10-year period in israel.listeria monocytogenes is a foodborne pathogen that causes life-threatening infections in elderly, immunocompromised, and pregnant women. in pregnancy it may cause fetal loss or a preterm delivery, and the neonate is prone to neonatal sepsis and death.201424973315
evaluation of the removal and destruction effect of a chlorine and thiamine dilaurylsulfate combined treatment on l. monocytogenes biofilm.the present study investigated the efficacy of single and combined treatment of both chlorine and thiamine dilaurylsulfate (tds) on the reduction of listeria monocytogenes biofilms in microtiter plate. the disinfectants used in this study were 50, 100, and 200 mg/l chlorine and 100, 500, and 1000 mg/l of tds. biofilm-forming index (bfi) and culturable cell count were used to evaluate the disinfectant assay. the highest bfi reduction was 0.80, achieved by the combination of 200 mg/l chlorine and ...201424971770
listeria monocytogenes induces ifnβ expression through an ifi16-, cgas- and sting-dependent pathway.listeria monocytogenes is a gram-positive facultative intracellular bacterium, which replicates in the cytoplasm of myeloid cells. interferon β (ifnβ) has been reported to play an important role in the mechanisms underlying listeria disease. although studies in murine cells have proposed the bacteria-derived cyclic-di-amp to be the key bacterial immunostimulatory molecule, the mechanism for ifnβ expression during l. monocytogenes infection in human myeloid cells remains unknown. here we report t ...201424970844
an unusual presentation of listeriosis: anemia and cutaneous manifestations.listeria monocytogenes is an intracellular pathogen causing food-borne disease. it usually affects the young as well as immunocompromised individuals and is associated with high mortality rates. cutaneous manifestations have rarely been described. we describe an interesting case of a traveller from the tropics presenting with cutaneous listeriosis and anemia.201424968680
misidentification of listeria monocytogenes by the vitek 2 system. 201424966361
listeria monocytogenes brainstem infection (rhombencephalitis) mimicking ischemic stroke.the frequency of listeria monocytogenes (lm) infection of the central nervous system is increasing. we report a patient recently treated with chemotherapeutic drugs for pulmonary adenocarcinoma who suddenly developed hemiparesis, was initially diagnosed with stroke, and was then found to be affected by lm rhombencephalitis accompanied by a brain abscess. lm meningoencephalitis mimicking ischemic stroke is rare but must be considered, especially in specific patients.201424961733
transfusion-related listeria monocytogenes infection in a patient with acute myeloid leukaemia. 201424960659
listeria monocytogenes-associated meningitis and arthritis in an immunocompetent 65-year-old woman: a case report.we report an unusual case of concurrent meningitis and infectious monoarthritis due to listeria monocytogenes in a 65-year-old woman presenting to our department with a transient gastrointestinal tract illness. during hospitalization the patient's neurological status deteriorated, presenting signs of meningeal irritation along with signs of inflammation and oedema of the right knee. blood cultures and cultures of the cerebrospinal fluid and of the sinovial fluid aspirate showed growth of l. mono ...201424955800
mycotic abdominal aortic aneurysm from listeria monocytogenes. 201424954294
genetic characterization of plasmid-associated triphenylmethane reductase in listeria monocytogenes.the enzyme triphenylmethane reductase (tmr) reduces toxic triphenylmethane dyes into colorless, nontoxic derivatives, and tmr-producing microorganisms have been proposed as bioremediation tools. analysis of the genome of listeria monocytogenes h7858 (1998-1999 hot dog outbreak) revealed that the plasmid (plm80) of this strain harboring a gene cassette (bcrabc) conferring resistance to benzalkonium chloride (bc) and other quaternary ammonium disinfectants also harbored a gene (tmr) highly homolog ...201424951782
the polycomb repressive complex 2 governs life and death of peripheral t cells.differentiation of naïve cd4(+) t cells into effector (th1, th2, and th17) and induced regulatory (itreg) t cells requires lineage-specifying transcription factors and epigenetic modifications that allow appropriate repression or activation of gene transcription. the epigenetic silencing of cytokine genes is associated with the repressive h3k27 trimethylation mark, mediated by the ezh2 or ezh1 methyltransferase components of the polycomb repressive complex 2 (prc2). here we show that silencing o ...201424951427
a fast, reliable, and sensitive method for detection and quantification of listeria monocytogenes and escherichia coli o157:h7 in ready-to-eat fresh-cut products by mpn-qpcr.in the present work we developed a mpn quantitative real-time pcr (mpn-qpcr) method for a fast and reliable detection and quantification of listeria monocytogenes and escherichia coli o157:h7 in minimally processed vegetables. in order to validate the proposed technique, the results were compared with conventional mpn followed by phenotypic and biochemical assays methods. when l. monocytogenes and e. coli o157:h7 were artificially inoculated in fresh-cut vegetables, a concentration as low as 1 c ...201424949460
use carum copticum essential oil for controlling the listeria monocytogenes growth in fish model system.this study was conducted to evaluate the antibacterial effect of carum copticum essential oil (ajowan eo) against listeria monocytogenes in fish model system. ajowan eo chemical composition was determined by gas chromatography/mass spectral analysis and the highest concentration of carum copticum essential oil without any significant changes on sensory properties of kutum fish (rutilus frisii kutum) was assigned. then the inhibitory effect of ajowan eo at different concentrations in presence of ...201424948918
control of listeria monocytogenes growth in soft cheeses by bacteriophage p100.the purpose of this study was to determine the effect of bacteriophage p100 on strains of listeria monocytogenes in artificially inoculated soft cheeses. a mix of l. monocytogenes 1/2a and scott a was inoculated in minas frescal and coalho cheeses (approximately 10(5) cfu/g) with the bacteriophage added thereafter (8.3 × 10(7) pfu/g). samples were analyzed immediately, and then stored at 10 °c for seven days. at time zero, 30 min post-infection, the bacteriophage p100 reduced l. monocytogenes co ...201424948908
role of host gtpases in infection by listeria monocytogenes.the bacterial pathogen listeria monocytogenes induces internalization into mammalian cells and uses actin-based motility to spread within tissues. listeria accomplishes this intracellular life cycle by exploiting or antagonizing several host gtpases. internalization into human cells is mediated by the bacterial surface proteins inla or inlb. these two modes of uptake each require a host actin polymerization pathway comprised of the gtpase rac1, nucleation promotion factors, and the arp2/3 comple ...201424948362
toxoplasma gondii profilin promotes recruitment of ly6chi ccr2+ inflammatory monocytes that can confer resistance to bacterial infection.ly6c+ inflammatory monocytes are essential to host defense against toxoplasma gondii, listeria monocytogenes and other infections. during t. gondii infection impaired inflammatory monocyte emigration results in severe inflammation and failure to control parasite replication. however, the t. gondii factors that elicit these monocytes are unknown. early studies from the remington laboratory showed that mice with a chronic t. gondii infection survive lethal co-infections with unrelated pathogens, i ...201424945711
listeria exploits damage and death to spread bad news.pathogenic listeria monocytogenes replicates within the host cytosol; little is known about how it transits from cell to cell, spreading infection. a recent study implicates infection-induced membrane damage as a trigger for efferocytosis, the recognition and uptake of dead cells, thereby tricking neighboring cells into taking up the invader.201424934861
bi-phasic growth of listeria monocytogenes in chemically defined medium at low temperatures.the present work reports a novel observation regarding the growth of l. monocytogenes in modified welshimer's broth (mwb) at low temperatures. specifically, the direct monitoring of the growth of l. monocytogenes scott a using plate count data revealed that the pathogen displays a bi-phasic growth pattern in mwb at 7 °c. this bi-phasic growth pattern is masked (not observed) when optical density (od) measurements are used to monitor growth due to the inability of od readings to detect l. monocyt ...201425016210
analysing and modelling the growth behaviour of listeria monocytogenes on rte cooked meat products after a high pressure treatment at 400 mpa.various predictive models are available for high pressure inactivation of listeria monocytogenes in food, but currently available models do not consider the growth kinetics of surviving cells during the subsequent storage of products. therefore, we characterised the growth of l. monocytogenes in sliced cooked meat products after a pressurization treatment. two inoculum levels (10(7) or 10(4) cfu/g) and two physiological states before pressurization (freeze-stressed or cold-adapted) were evaluate ...201425016207
assessment of salmonella and listeria monocytogenes level in ready-to-cook poultry meat: effect of various high pressure treatments and potassium lactate concentrations.the objective of this study was to develop a probabilistic model in order to determine the contamination level of salmonella and listeria monocytogenes in ready-to-cook poultry meat, after a high pressure (hp) treatment. the model included four steps: i) reception of raw meat materials, mincing and mixing meat, ii) partitioning and packaging into 200-g modified atmosphere packs, iii) high pressure treatment of the meat, and iv) storage in chilled conditions until the end of the shelf-life. the m ...201425016206
purification and mass spectrometry based characterization of a pediocin produced by pediococcus acidilactici 13.bacteriocins are antimicrobial peptides produced by several bacterial species. among the bacteriocins pediocin-like bacteriocins have a significant inhibitory activity on the foodborne pathogens especially on listeria monocytogenes. this study aims to select a simple and usable purification method to purify/concentrate the antimicrobial peptide and characterization of the bacteriocin produced by pediococcus acidilactici 13 by using proteomic approaches which is a recent omic technology. for puri ...201425015266
a btla-mediated bait and switch strategy permits listeria expansion in cd8α(+) dcs to promote long-term t cell responses.listeria monocytogenes infected cd8α(+) dcs in the spleen are essential for cd8(+) t cell generation. cd8α(+) dcs are also necessary for listeria expansion and dissemination within the host. the mechanisms that regulate cd8α(+) dcs to allow listeria expansion are unclear. we find that activating the b and t lymphocyte attenuator (btla), a coinhibitory receptor for t cells, suppresses, while blocking btla enhances, both the primary and memory cd8 t cell responses against listeria. btla(-/-) mice ...201425011109
characterization of listeria monocytogenes strains isolated during 2011-2013 from human infections in switzerland.listeria monocytogenes, an emerging foodborne pathogen, can cause in the population at risk severe infections that are associated with high case fatality rates. a total of 93 l. monocytogenes strains isolated from different patients in switzerland from july 2011 to september 2013 were further characterized. septicemia was reported for 74.2% of the patients, meningitis for 10.8%, and abortion for 3.2%. the majority of the strains belonged to serotype 1/2a (n=58) followed by serotype 4b (n=28), 1/ ...201425007293
reservoirs of listeria species in three environmental ecosystems.soil and water are suggested to represent pivotal niches for the transmission of listeria monocytogenes to plant material, animals, and the food chain. in the present study, 467 soil and 68 water samples were collected in 12 distinct geological and ecological sites in austria from 2007 to 2009. listeria was present in 30% and 26% of the investigated soil and water samples, respectively. generally, the most dominant species in soil and water samples were listeria seeligeri, l. innocua, and l. iva ...201425002422
response to comment on "tim-3 directly enhances cd8 t cell responses to acute listeria monocytogenes infection". 201424994908
comment on "tim-3 directly enhances cd8 t cell responses to acute listeria monocytogenes infection". 201424994907
perinatal immunization with vaccine-grade listeria monocytogenes provides protection against murine th2 airway inflammation.asthma is a chronic respiratory disorder that leads to inflammation and narrowing of the airways. its global prevalence has attained epidemic levels and treatment options that reach beyond temporary relief of symptoms are urgently needed. since the processes leading to clinically symptomatic asthma start early in life, we set out to systematically evaluate a neonatal immunotherapeutic based on listeria monocytogenes (lm) for the control of allergic sensitization.201424991458
schistosoma mansoni soluble egg antigens enhance listeria monocytogenes vector hiv-1 vaccine induction of cytotoxic t cells.vaccines are an important public health measure for prevention and treatment of diseases. in addition to the vaccine immunogen, many vaccines incorporate adjuvants to stimulate the recipient's immune system and enhance vaccine-specific responses. while vaccine development has advanced from attenuated organism to recombinant protein or use of plasmid dna, the development of new adjuvants that safely increase immune responses has not kept pace. previous studies have shown that the complex mixture ...201424990901
inactivation kinetics of escherichia coli o157:h7, salmonella enterica serovar typhimurium, and listeria monocytogenes in ready-to-eat sliced ham by near-infrared heating at different radiation intensities.the aim of this study was to investigate the inactivation kinetics of salmonella enterica serovar typhimurium, escherichia coli o157:h7, and listeria monocytogenes on ready-to-eat sliced ham by near-infrared (nir) heating as a function of the processing parameter, radiation intensity. precooked ham slices inoculated with the three pathogens were treated at different nir intensities (ca. 100, 150, and 200 μw/cm(2)/nm). an increase in the applied radiation intensity resulted in a gradual increase ...201424988034
metal-chelating active packaging film enhances lysozyme inhibition of listeria monocytogenes.several studies have demonstrated that metal chelators enhance the antimicrobial activity of lysozyme. this study examined the effect of metal-chelating active packaging film on the antimicrobial activity of lysozyme against listeria monocytogenes. polypropylene films were surface modified by photoinitiated graft polymerization of acrylic acid (pp-g-paa) from the food contact surface of the films to impart chelating activity based on electrostatic interactions. pp-g-paa exhibited a carboxylic ac ...201424988022
low occurrence of listeria monocytogenes on bovine hides and carcasses in minas gerais state, brazil: molecular characterization and antimicrobial resistance.listeria monocytogenes occurrence was assessed in three slaughterhouses located in minas gerais state, brazil, by analysis of 209 bovine carcasses. four sponge samples were obtained from each carcass in different steps (a, from hide, before bleeding; b, after hide removal; c, after evisceration; and d, after end washing), resulting in a total of 836 samples. the samples were tested for the presence of l. monocytogenes according to the international organization for standardization 11290-1, and p ...201424988021
the receptor for the complement c3a anaphylatoxin (c3ar) provides host protection against listeria monocytogenes-induced apoptosis.listeria monocytogenes is a gram-positive intracellular bacterium that is acquired through tainted food and may lead to systemic infection and possible death. despite the importance of the innate immune system in fighting l. monocytogenes infection, little is known about the role of complement and its activation products, including the potent c3a anaphylatoxin. in a model of systemic l. monocytogenes infection, we show that mice lacking the receptor for c3a (c3ar(-/-)) are significantly more sen ...201424981453
modeling the growth of listeria monocytogenes on the surface of smear- or mold-ripened cheese.surface-ripened cheeses are matured by means of manual or mechanical technologies posing a risk of cross-contamination, if any cheeses are contaminated with listeria monocytogenes. in predictive microbiology, primary models are used to describe microbial responses, such as growth rate over time and secondary models explain how those responses change with environmental factors. in this way, primary models were used to assess the growth rate of l. monocytogenes during ripening of the cheeses and t ...201425072033
systemic listeria monocytogenes infection in a 2-year-old immunocompetent child.central nervous system infection and sepsis are the most frequently observed clinical presentations of listeriosis infection; however, they are rare in immunocompetent children beyond the neonatal period. in the presented case, we described gastrointestinal involvement, subacute meningitis, sinusitis and sepsis in a two-year-old previously healthy child with acute infection caused by listeria monocytogenes. we suggest that the infection was probably enhanced by an inappropriate corticosteroid tr ...201425060681
draft genome sequence of listeria monocytogenes strain li0521 (syn. hpb7171), isolated in 1983 during an outbreak in massachusetts caused by contaminated cheese.listeria monocytogenes, a pathogenic food-borne bacterium, is the causative agent of both sporadic and outbreak cases of human listeriosis. here, we present the genome sequence of l. monocytogenes reference strain li0521, isolated during an outbreak involving contaminated cheese, which has been used as the model during several proteomic studies.201425059873
listeria meningitis and resultant symptomatic hydrocephalus complicating infliximab treatment for ulcerative colitis.listeria monocytogenes, an uncommon pathogen, should be considered by clinicians as a source of sepsis and meningitis in the immunocompromised individuals, including those on anti-tnf alpha agents. immunosuppressant agents including biologic therapies have transformed the management of various rheumatological and dermatological conditions.(1) we report a case of life-threatening l. monocytogenes sepsis and meningitis in a 75-year-old man receiving infliximab for severe ulcerative colitis (uc).201425057381
genetic classification of listeria monocytogenes serotype 4b strains, including epidemic clones, isolated from retail meat in the tokyo metropolitan area.a food-borne pathogen, listeria monocytogenes serotype 4b, has been frequently isolated from patients with listeriosis, and numerous outbreaks of listeriosis are associated with this serotype. in the present study, we performed subtyping of l. monocytogenes serotype 4b strains on the basis of genetic analyses. thirty-four isolates of serotype 4b were classified into 8 genotypes, namely genotypes 12, 15, 16, 17, 18, 23, 24, and 25, on the basis of the sequence for the partial iap gene. genetic an ...201425056070
instantlabs listeria monocytogenes food safety kit. performance tested method 051304.the instantlabs listeria monocytogenes food safety kit was validated against the international organization for standardization (iso) reference method 11290-1 for the detection of listeria monocytogenes and other listeria species. the matrixes (stainless steel, sealed concrete, ice cream, whole milk, cheddar cheese, raw shrimp, hot dogs, deli turkey, and lettuce) were inoculated with approximately 1 cfu/test portion of l. monocytogenes to generate fractional positives (5-15) in 20 inoculated sam ...201425051634
instantlabs listeria species food safety kit. performance tested methods 041304.the instantlabs listeria species food safetykitwas validated against the international organization for standardization (iso) reference method 11290-1 for the detection of listeria monocytogenes and other listeria species. the matrixes (stainless steel, sealed concrete, cheddar cheese, raw shrimp, and hot dogs) were inoculated with approximately 1 cfu/test portion of various listeria species to generate fractional positives (5-15) in 20 inoculated samples. enrichments were also fractionally inoc ...201425051633
deletion of the membrane protein lmo0412 increases the virulence of listeria monocytogenes.listeria monocytogenes is a facultative intracellular pathogen that causes gastroenteritis, meningitis, encephalitis and maternofetal infections. 20-30% of eubacterial orfs are predicted to encode membrane proteins. the bacterial cytoplasmic membrane is a macromolecular structure, which plays a key role for the pathogenesis. despite this, little knowledge exists regarding the function of cytoplasmic membrane proteins of listeria during infection. here, we investigated a predicted membrane protei ...201425051038
assessment of oligogalacturonide from citrus pectin as a potential antibacterial agent against foodborne pathogens.foodborne diseases are an important public health problem in the world. the bacterial resistance against presently used antibiotics is becoming a public health issue; hence, the discovery of new antimicrobial agents from natural sources attracts a lot of attention. antibacterial activities of oligogalacturonide from commercial microbial pectic enzyme (cpe) treated citrus pectin, which exhibits antioxidant and antitumor activities, against 4 foodborne pathogens including salmonella typhimurium, s ...201425048440
serogrouping and pulsed-field gel electrophoresis analysis of listeria monocytogenes isolates from cases of human infection in hungary 2004–2012 molecular typing of listeria monocytogenes in hungary.eighty isolates of listeria monocytogenes cultured from human infections in hungary between 2004 and 2012 were serotyped by the pcr technique of doumithet al. [9] and characterised by pulsed-field gel electrophoresis (pfge). most of the isolates belonged to two serogroups: 53 isolates (66.3%) to serovar group 4b,4d,4e and 21isolates (25.8%) to serogroup 1/2a,3a. although many pulsotypes were identified a particular pulsotype proved highly excelling comprising of 31 isolates after digestion by bo ...201425046881
dnase i and proteinase k impair listeria monocytogenes biofilm formation and induce dispersal of pre-existing biofilms.current sanitation methods in the food industry are not always sufficient for prevention or dispersal of listeria monocytogenes biofilms. here, we determined if prevention of adherence or dispersal of existing biofilms could occur if biofilm matrix components were disrupted enzymatically. addition of dnase during biofilm formation reduced attachment (<50% of control) to polystyrene. treatment of established 72h biofilms with 100μg/ml of dnase for 24h induced incomplete biofilm dispersal, with <2 ...201425043896
use of mild irradiation doses to control pathogenic bacteria on meat trimmings for production of patties aiming at provoking minimal changes in quality attributes.the objectives of the present work were to assess the use of moderate doses of gamma irradiation (2 to 5 kgy) and to reduce the risk of pathogen presence without altering the quality attributes of bovine trimmings and of patties made of irradiated trimmings. microbiological indicators (coliforms, pseudomonas spp and mesophilic aerobic counts), physicochemical indicators (ph, color and tiobarbituric acid) and sensory changes were evaluated during storage. 5 kgy irradiation doses slightly increase ...201425042241
inhibitory effects of the κ-casein macropeptide isolated from milk protein on the biofilm formation and virulence of listeria monocytogenes.we demonstrate the inhibitory effects of κ-casein macropeptide (cmp) on the biofilm formation and virulence of listeria monocytogenes scott a. the inhibition of biofilm formation by cmp was initially investigated by using the protocol applied for the 96-well microtiter plate assay. low concentrations of cmp (0.1, 0.2, 0.3, 0.4, and 0.5 mg/ml) that were tested resulted in a profound inhibitory effect on biofilm formation at a concentration of 0.4 mg/ml. cmp also significantly repressed the transc ...201425036840
serial transfer of single-cell-derived immunocompetence reveals stemness of cd8(+) central memory t cells.maintenance of immunological memory has been proposed to rely on stem-cell-like lymphocytes. however, data supporting this hypothesis are focused on the developmental potential of lymphocyte populations and are thus insufficient to establish the functional hallmarks of stemness. here, we investigated self-renewal capacity and multipotency of individual memory lymphocytes by in vivo fate mapping of cd8(+) t cells and their descendants across three generations of serial single-cell adoptive transf ...201425035956
the effect of oleanolic and ursolic acids on the hemolytic properties and biofilm formation of listeria monocytogenes.oleanolic acid and ursolic acid are pentacyclic triterpenoids isolated from a variety of medicinal plants, which have antibacterial activity. listeria monocytogenes is a gram-positive facultative pathogen, being the causative agent of listeriosis. the present study was carried out to evaluate the in vitro effect of sub-inhibitory concentrations of both triterpene acids on the pathogenicity determinants of l. monocytogenes: their hemolytic activity and biofilm forming ability. oleanolic and ursol ...201425033658
the first invertebrate rig-i-like receptor (rlr) homolog gene in the pacific oyster crassostrea gigas.retinoic acid-inducible gene i (rig-i)-like receptor (rlr) is a pivotal receptor that detects numerous rna and dna viruses and mediates the innate induction of interferons and pro-inflammatory cytokines upon viral infection. in the present study, we cloned and characterized the first rig-i gene in a marine mollusk, crassostrea gigas, and designated it as cgrig-i. the full-length cgrig-i cdna is 3436 bp, including 5'- and 3'-untranslated regions (utrs) of 93 bp and 286 bp, respectively, and an op ...201425107697
effect of lauric arginate, nisin z, and a combination against several food-related bacteria.the effects of lauric arginate (lae) and nisin z, alone or in combination, on cell damage were investigated against escherichia coli o157:h7, listeria monocytogenes and brochothrix thermosphacta, by scanning electron microscopy (sem) and transmission electron microscopy (tem) observations, efflux of potassium and phosphate ions, and growth inhibition. a combination of lae with nisin z caused severe and dramatic changes in the cytoplasmic membrane and cell lysis of both gram-positive and gram-neg ...201425106040
cyclic di-gmp-dependent signaling pathways in the pathogenic firmicute listeria monocytogenes.we characterized key components and major targets of the c-di-gmp signaling pathways in the foodborne pathogen listeria monocytogenes, identified a new c-di-gmp-inducible exopolysaccharide responsible for motility inhibition, cell aggregation, and enhanced tolerance to disinfectants and desiccation, and provided first insights into the role of c-di-gmp signaling in listerial virulence. genome-wide genetic and biochemical analyses of c-di-gmp signaling pathways revealed that l. monocytogenes has ...201425101646
management of pregnant women with presumptive exposure to listeria monocytogenes.: listeriosis is predominantly a foodborne illness, with sporadic and outbreak-related cases tied to consumption of food contaminated with listeria (listeria monocytogenes). the incidence of listeriosis associated with pregnancy is approximately 13 times higher than in the general population. maternal infection may present as a nonspecific, flu-like illness with fever, myalgia, backache, and headache, often preceded by diarrhea or other gastrointestinal symptoms. however, fetal and neonatal infe ...201425098360
pediococcus pentosaceus sb83 as a potential probiotic incorporated in a liquid system for vaginal delivery.pediococcus pentosaceus sb83 is a bacteriocinogenic culture having potential use as a vaginal probiotic. the objective of this study was to evaluate the behaviour of p. pentosaceus sb83 incorporated in a liquid system for eventually formulating a gel for vaginal delivery. the vaginal probiotic incorporated into glycerol was able to survive in simulated vaginal fluid at normal vaginal ph (4.2) and at ph of vaginal infections (5.5 and 6.5). the probiotic can be stored at 4 °c for a longer period o ...201425097107
small molecule deubiquitinase inhibitors promote macrophage anti-infective capacity.the global spread of anti-microbial resistance requires urgent attention, and diverse alternative strategies have been suggested to address this public health concern. host-directed immunomodulatory therapies represent one approach that could reduce selection for resistant bacterial strains. recently, the small molecule deubiquitinase inhibitor wp1130 was reported as a potential anti-infective drug against important human food-borne pathogens, notably listeria monocytogenes and noroviruses. util ...201425093325
integrated air stream micromixer for performing bioanalytical assays on a plastic chip.this paper describes the design, functioning and use of an integrated mixer that relies on air flux to agitate microliter entities of fluid in an embedded microfluidic cavity. the system was fabricated from multiple layers of a thermoplastic elastomer and features circuits for both liquid and air supply along with pneumatic valves for process control. internally-dyed polymer particles have been used to visualize flow within the fluid phase during agitation. numerical modelling of the micromixer ...201425091476
Refresh
firstprev
...21222324252627282930...
nextlast
Displaying items 2001 - 2100 of 16792