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inactivation of the wall-associated de-n-acetylase (pgda) of listeria monocytogenes results in greater susceptibility of the cells to induced autolysis.several species of gram-positive bacteria have cell wall peptidoglycan (syn. murein) in which not all of the sugar moieties are n-acetylated. this has recently been shown to be a secondary effect, caused by the action of a peptidoglycan n-acetylglucosamine deacetylase. we have found that the opportunistic pathogen listeria monocytogenes is unusual in having three enzymes with such activity, two of which remain in the cytoplasm. here, we examine the enzyme (pgda) that crosses the cytoplasmic memb ...200919809250
pcr experion automated electrophoresis system to detect listeria monocytogenes in foods.listeria monocytogenes is frequently found as a contaminant in raw and ready-to-eat foods. the ability of l. monocytogenes to multiply at refrigeration temperatures and to grow in a wide range of ph values is of particular concern for food safety. according to the european union regulation on microbiological criteria for foodstuffs, l. monocytogenes must be absent in some categories of ready-to-eat foods. the standard microbiological method for l. monocytogenes detection in foods (iso 11290-1: 1 ...200919810054
neonatal immunization with listeria monocytogenes induces t cells with an adult-like avidity, sensitivity, and tcr-vbeta repertoire, and does not adversely impact the response to boosting.listeria monocytogenes (lm) holds promise as a neonatal vaccine vehicle. here we show that lm immunized neonatal mice reached maximal ag-specific cd8(+) t cell expansion after only a single immunization, while adults required two doses. ag-specific cd4(+) t cell expansion in both age groups required a boost to reach its peak. neither functional avidity, sensitivity, nor the tcr-vbeta repertoire of the ag-specific t cells differed between mice immunized as neonates or adults. lastly, neonatal imm ...200919796722
superior protective immunity against murine listeriosis by combined vaccination with cpg dna and recombinant salmonella enterica serovar typhimurium.preexisting antivector immunity can severely compromise the ability of salmonella enterica serovar typhimurium live vaccines to induce protective cd8 t-cell frequencies after type iii secretion system-mediated heterologous protein translocation in orally immunized mice. to circumvent this problem, we injected cpg dna admixed to the immunodominant p60(217-225) peptide from listeria monocytogenes subcutaneously into balb/c mice and coadministered a p60-translocating salmonella strain by the orogas ...200919797070
inactivation of listeria monocytogenes on unpackaged and vacuum-packaged chicken frankfurters using pulsed uv-light.the effectiveness of pulsed uv-light on the microbial load and quality of unpackaged and vacuum-packaged chicken frankfurters was investigated. samples were inoculated with listeria monocytogenes scott a on the top surfaces, and then treated with pulsed uv-light for 5, 15, 30, 45, and 60 s at 5, 8, and 13 cm distance from the quartz window in a pulsed uv-light chamber. log reductions (cfu/cm(2)) on unpackaged samples were between 0.3 and 1.9 after 5-s treatment at 13 cm and 60-s treatment at 5 c ...200919799670
edible apple film wraps containing plant antimicrobials inactivate foodborne pathogens on meat and poultry products.apple-based edible films containing plant antimicrobials were evaluated for their activity against pathogenic bacteria on meat and poultry products. salmonella enterica or e. coli o157:h7 (10(7) cfu/g) cultures were surface inoculated on chicken breasts and listeria monocytogenes (10(6) cfu/g) on ham. the inoculated products were then wrapped with edible films containing 3 concentrations (0.5%, 1.5%, and 3%) of cinnamaldehyde or carvacrol. following incubation at either 23 or 4 degrees c for 72 ...200919799671
universal primer-multiplex pcr approach for simultaneous detection of escherichia coli, listeria monocytogenes, and salmonella spp. in food samples.escherichia coli, listeria monocytogenes, and salmonella spp. are 3 kinds of the most important food-borne human pathogens. traditional microbiological analysis is labor-intensive, time-consuming, and easily contaminated, thus producing false positive signals; it also involves much subjectivity judgments. multiplex-pcr could be applied to detect multiple target organisms simultaneously to save time and labor, but there is always disproportionate amplification resulting from the disparity of diff ...200919799672
microwave oven heating for inactivation of listeria monocytogenes on frankfurters before consumption.microwave oven heating was evaluated for inactivation of listeria monocytogenes on inoculated and stored frankfurters. frankfurters formulated without/with 1.5% potassium lactate and 0.1% sodium diacetate were inoculated with l. monocytogenes (1.9 +/- 0.2 log cfu/cm(2)), vacuum-packaged, and stored (4 degrees c) to simulate conditions prior to purchase by consumers. at storage days 18, 36, and 54, packages were opened and placed at 7 degrees c, simulating aerobic storage in a household refrigera ...200919799673
antibrowning and antimicrobial properties of sodium acid sulfate in apple slices.there are few available compounds that can both control browning and enhance microbial safety of fresh-cut fruits. in the present study, the antibrowning ability of sodium acid sulfate (sas) on "granny smith" apple slices was first investigated in terms of optimum concentration and treatment time. in a separate experiment, the apple slices were treated with water or 3% of sas, calcium ascorbate, citric acid, or acidified calcium sulfate for 5 min. total plate count, color, firmness, and tissue d ...200920492119
sensitivity of listeria monocytogenes scott a to nisin and diacetyl after starvation in sodium phosphate buffered saline.this study determined the effectiveness of nisin and diacetyl to inhibit the growth of listeria monocytogenes (lm) under normal cell cultivation and starvation conditions in sodium phosphate buffered saline (spbs). inhibitory effects of nisin at 320 or 1000 au/ml or diacetyl at 0.25%, 0.50%, or 1.0% and combinations on lm in brain heart infusion (bhi), spbs, and potassium phosphate buffered saline (kpbs) were determined on bhia (nonselective medium) and palcam (selective medium) agar at 0 and 2 ...200920492120
effect of organic acids and plant extracts on escherichia coli o157:h7, listeria monocytogenes, and salmonella typhimurium in broth culture model and chicken meat systems.foodborne illness due to consumption of products contaminated with salmonella typhimurium (s.t.), listeria monocytogenes (l.m.), and escherichia coli o157:h7 (e.c.) results in many deaths and significant economic losses each year. in this study, acetic (aa), citric acid (ca), lactic acid (la), malic acid (ma), and tartaric acid (ta) and grape seed (gs), green tea (gt), bitter melon seed (bms), rasum, and fenugreek (fg) extracts were investigated as inhibitors against s.t., l.m., and e.c. in both ...200920492123
effect of salt, smoke compound, and temperature on the survival of listeria monocytogenes in salmon during simulated smoking processes.the objectives of this study were to examine and develop a model to describe the survival of listeria monocytogenes in salmon as affected by salt, smoke compound (phenol), and smoking process temperature. cooked minced salmon containing selected levels of salt (0%, 2%, 4%, and 6%) and smoke compound (0, 5, 10, and 15 ppm phenol) were inoculated with a 6-strain mixture of l. monocytogenes to an inoculum level of 6.0 log(10) cfu/g. the populations of l. monocytogenes in salmon during processing at ...200920492124
dnase i inhibits a late phase of reactive oxygen species production in neutrophils.neutrophils kill bacteria on extracellular complexes of dna fibers and bactericidal proteins known as neutrophil extracellular traps (nets). the net composition and the bactericidal mechanisms they use are not fully understood. here, we show that treatment with deoxyribonuclease (dnase i) impairs a late oxidative response elicited by gram-positive and gram-negative bacteria and also by phorbol ester. isoluminol-dependent chemiluminescence elicited by opsonized listeria monocytogenes-stimulated n ...200920375609
food standards commission targets dangerous bacteria, chemicals. 200920377055
[listeria monocytogenes infection in a total knee arthroplasty].acute blood borne prosthetic infections occur in patients with an asymptomatic prosthesis that, after an infection involving bacteremia, produces bacterial implantation in the prosthesis and causes an acute infection. this type of infection is usually caused by gram positive cocci, streptococci and staphylococci. we present the clinical case of a patient without a history of immunodeficiency, who had an acute blood borne knee prosthetic infection caused by listeria monocytogenes.200920336882
survey of listeria monocytogenes and other listeria sp. contamination in different common ready-to-eat food products in jordan.incidence and contamination levels of different listeria monocytogenes serovars and different listeria sp. in 360 samples of common ready-to-eat food products in jordan were investigated. the presence of l. monocytogenes was determined using en iso protocol and confirmed using pcr technique. five listeria sp.: l. monocytogenes, l. innocua, l. ivanovvi, l. welshimeri and l. seeligeri were isolated. l. monocytogenes was isolated from 19 samples (5.3%), from 6 rte dairy samples; 6 rte vegetables sa ...200920180325
phenolics and anthocyanins in berries of european cranberry and their antimicrobial activity.european cranberry is a berry plant rich in biologically active substances, making it valued by both the phyto-pharmaceutical and food industries. the aim of this study was to examine the accumulation of phenolic compounds and anthocyanins in berries of european cranberry and to assess their antibacterial activity. material and methods: different wild clones of european cranberry were investigated according to berry weight and the amounts of total phenolics and anthocyanins. anthocyanin profiles ...200920173403
co-infection of market-age turkeys with escherichia coli and listeria monocytogenes in two stress models.we have hypothesized that stress-induced subclinical infection of turkeys with listeria monocytogenes may be an overlooked source of processing plant contamination, and we have shown that concurrent escherichia coli challenge can increase l. monocytogenes colonization. the objective of this study was to determine the effects of dexamethasone (dex) immunosuppressive treatment and transport stress on the isolation of l. monocytogenes in an e. coli-l. monocytogenes challenge model. thirteen-week-ol ...200920095148
an analysis of the factors for microbial contamination risk for pork at slaughterhouses in korea using the logit model.to assess the effect of slaughtering practices on the probability of microbial contamination at slaughterhouses in korea, 840 samples from 8 slaughterhouses were collected and 50 factors observed for 2 yr. target microorganisms were salmonella spp. and listeria monocytogenes and 20 contaminated samples were found. twenty-one out of 50 factors were identified as possible sources of microbial contamination. to narrow down the more critical factors and quantify the effects, simple regression analys ...200920077220
cutaneous listeria infection.this case introduces an unusual cutaneous manifestation of a potentially life-threatening infection. the circumstances of the inoculation are key to explaining both the cutaneous signs and how an individual who does not belong to what would be considered a conventional 'at risk' group developed systemic infection. however, cutaneous infection with listeria monocytogenes could be considered an occupational hazard for those working with livestock.200920081597
[risk assessment of listeria monocytogenes in deli meats and vegetable salads].to analysis risk from listeria monocytogenes in deli meats and vegetable salads.200920137560
estimation of the pod function and the lod of a qualitative microbiological measurement method.qualitative microbiological measurement methods in which the measurement results are either 0 (microorganism not detected) or 1 (microorganism detected) are discussed. the performance of such a measurement method is described by its probability of detection as a function of the contamination (cfu/g or cfu/ml) of the test material, or by the lod(p), i.e., the contamination that is detected (measurement result 1) with a specified probability p. a complementary log-log model was used to statistical ...200920166595
antibacterial and antioxidant activities of the essential oil of artemisia echegarayi hieron. (asteraceae).artemisia echegarayi hieron. (asteraceae) is commonly known in argentina as "ajenjo". many studies report high efficacy of essential oils against food-borne pathogenic bacteria. the antimicrobial activity and minimal inhibitory concentration of a. echegarayi essential oil were evaluated against seven bacterial species of significant importance in food hygiene, by using the disc diffusion assay and the micro-well dilution method, respectively. volatile components of the extract were analyzed by g ...200920085186
characterization of bacteriocin produced by streptococcus bovis j2 40-2 isolated from traditional fermented milk 'dahi'.a bacteriocin-producing strain streptococcus bovis j2 40-2 was isolated from traditional fermented milk 'dahi' in bangladesh. despite its narrow antimicrobial spectrum, it showed strong antimicrobial activity against extremely challenging and problematic organisms in foods, such as listeria monocytogenes. bacteriocin was sensitive to several proteolytic enzymes and showed antimicrobial activity over a wide ph range of 2.0-10.0. it was stable when heated to 110 degrees c for 20 min, but lost 25% ...200920163471
[prokaryotic expression of listeria monocytogene (lm) hly and development of monoclonal antibodies against listeriolysin o (llo)].in order to study the pathogenesis of listeria monocytogenes (lm), we cloned listeriolysin gene into prokaryotic expression vector pet21a. the expression vector was transformed into escherichia coli bl21 for expression of listeriolysin o (llo). llo-his tag fusion protein was purified with a ni-nta affinity column and was used as an immunogen to vaccinate balb/c mice. hybridomas were developed by fusing mouse myeloma cells sp2/0 and splenocytes from the immunized mice and screened with purified l ...200920222463
the impact of environmental stress on listeria monocytogenes virulence.listeria monocytogenes, a significant food-borne pathogen, must defy a variety of conditions encountered in the food environment and during the infection process. in reaction to adverse conditions, the bacteria significantly change their metabolism, inducing a stress response which is mediated by a range of alternative sigma factors. the extent of the response to stress was shown to vary in the l. monocytogenes population. according to recent evidence a major l. monocytogenes alternative sigma f ...200920169937
sanitizing effect of salts on experimentally inoculated organisms on pork carcasses.pork forequarters procured from freshly slaughtered animals were decontaminated with hot water and inoculated with staphylococcus aureus, escherichia coli, salmonella typhimurium, yersinia enterocolitica, listeria monocytogenes, serratia marcescens, pseudomonas aeruginosa and proteusvulgaris. the forequarters were individually spray washed with 5% potassium sorbate and a combination of 5% sodium chloride and 2.5% each of sodium acetate, sodium citrate, sodium lactate and potassium sorbate soluti ...200920416620
inactivation kinetics of listeria monocytogenes, salmonellaenterica serovar typhimurium, and campylobacter jejuni in ready-to-eat sliced ham using uv-c irradiation.to investigate the applicability of uv-c irradiation on the inactivation of foodborne pathogenic bacteria in ready-to-eat sliced ham, uv-c treatment was evaluated. irradiation dose required for 90% reduction of the populations of listeria monocytogenes, salmonellaenterica serovar typhimurium, and campylobacter jejuni were determined to be 2.48, 2.39, and 2.18j/m(2). ready-to-eat sliced hams were inoculated with the pathogens and irradiated with uv-c light of 1000, 2000, 4000, 6000, and 8000j/m(2 ...200920416652
high prevalence, low counts and uncommon serotypes of listeria monocytogenes in linguiça, a brazilian fresh pork sausage.linguiça is a highly popular and appreciated pork product in brazil, frequently consumed undercooked. aiming at collection of data for a future risk assessment, this study evaluated the prevalence and counts of listeria monocytogenes in linguiça samples collected at retail level in sao paulo, sp, brazil. iso methods were used for detection and enumeration of the pathogen (11290-1 and 11290-2, respectively). isolates were submitted to simplex-pcr for hlya gene and those with biochemical features ...200920416665
evaluation of the effect of defrosting practices of ground beef on the heat tolerance of listeria monocytogenes and salmonella enteritidis.the effect of common defrosting practices of ground beef, including (i) defrosting in the refrigerator (5 degrees c for 15h), (ii) defrosting at room temperature (25 degrees c for 12h) and (iii) defrosting in the microwave, on the heat tolerance of artificially inoculated listeria monocytogenes and salmonella enteritidis, was studied. the thermal inactivation of s. enteritidis was not, overall, affected by defrosting practices. in contrast, defrosting at room temperature resulted, overall, in an ...200920416679
effects of supercritical carbon dioxide treatment against generic escherichia coli, listeria monocytogenes, salmonella typhimurium, and e. coli o157:h7 in marinades and marinated pork.this study was conducted to evaluate the effects of supercritical carbon dioxide (sc-co(2)) treatment on soy sauce and hot-pepper paste marinades, as well as in marinated pork products, for the inhibition of generic escherichia coli, listeria monocytogenes, salmonella typhimurium, and e. coli o157:h7. sc-co(2) was more effective at destroying foodborne pathogens when it was applied to the marinades than the marinated products. sc-co(2) treatment at 14mpa and 45 degrees c for 40min resulted in a ...200920416694
high bacterial contamination of pig tonsils at slaughter.food-borne zoonoses have a major health impact in industrial countries. campylobacter spp., salmonella enterica, yersinia enterocolitica and listeria monocytogenes are high-risk food-borne zoonotic hazards in finishing pigs. the objectives of this work were (1) to study the isolation rate of pathogenic y. enterocolitica, salmonella spp., campylobacter spp. and l. monocytogenes in the tonsils and feces and (2) to determine the number of mesophilic aerobic bacteria (mab) and escherichia coli in th ...200920416719
influence of farming methods on microbiological contamination and prevalence of resistance to antimicrobial drugs in isolates from beef.the presence of escherichia coli, staphylococcus aureus, listeria monocytogenes and salmonella spp. was determined in 75 samples of conventional beef and in 75 samples of organic beef. all samples came from cattle slaughtered and processed in the same slaughterhouse and quartering room. a total of 180 e. coli, 180 s. aureus and 98 l. monocytogenes strains were analyzed by an agar disk diffusion assay for their resistance to 11 antimicrobials, for the case of e. coli and s. aureus, or 9 antimicro ...200920416735
a modeled structure for amidase-03 from bacillus anthracis.homology models of amidase-03 from bacillus anthracis were constructed using modeller (9v2). modeller constructs protein models using an automated approach for comparative protein structure modeling by the satisfaction of spatial restraints. a template structure of listeria monocytogenes bacteriophage psa endolysin plypsa (pdb id: 1xov) was selected from protein databank (pdb) using blastp with blosum62 sequence alignment scoring matrix. we generated five models using the modeller default routin ...200920975917
[survival strategy of intracellular bacteria in macrophages]. 200921089530
anti-angiogenesis immunotherapy induces epitope spreading to her-2/neu resulting in breast tumor immunoediting.targeting tumors using cancer vaccine-therapeutics has several advantages including the induction of long-term immunity, prime boost strategies for additional treatments and reduced side effects compared to conventional chemotherapeutics. however, one problem in targeting tumor antigens directly is that this can lead to antigen loss or immunoediting. we hypothesized that directing the immune response to a normal cell type required for tumor growth and survival could provide a more stable immunot ...200921197144
specific and rapid quantification of viable listeria monocytogenes using fluorescence in situ hybridization in combination with filter cultivation.we developed a new method that rapidly and specifically enumerates only viable listeria monocytogenes in food using fluorescence in situ hybridization in combination with filter cultivation (fishfc). viable l. monocytogenes could be specifically quantified within 16 h using an alexa647-labeled mrl-2 probe. the coefficient of the correlation between the new method and the conventional plating method was 0.959.200921566384
listeria monocytogenes' step-like response to sub-lethal concentrations of nisin.microbial safety of food products is often accomplished by the formulation of food-grade preservatives into the product. because of the growing consumer demand for natural substances (including preservatives) in the composition of consumed foods, there is also a growing interest in the natural antimicrobial nisin, which has generally recognized as safe (gras) status for certain applications. during the products storage time, concentrations of preservative(s) are decreasing, which may eventually ...200926783172
suppression of listeria monocytogenes scott a in fluid milk by free and liposome-entrapped nisin.nisin is an antimicrobial polypeptide inhibitory toward gram-positive bacterial pathogens, including listeria monocytogenes. encapsulating nisin in lipid nanocapsules (i.e., liposomes) has been shown to protect antimicrobial functionality in complex food matrices. the capacity of liposomes to encapsulate a fluorescent reporter was determined via spectroscopy. survival and growth of l. monocytogenes incubated in fluid milk containing 50 iu/ml free or liposome-entrapped nisin was assayed via perio ...200926783171
the acid tolerance response alters membrane fluidity and induces nisin resistance in listeria monocytogenes.the ability of l. monocytogenes cells to adapt to a variety of stressors contributes to its growth in a wide range of foods. the present study examines the effect of acid and of the acid tolerance response (atr) on membrane fluidity and on the organism's resistance to acid and to the bacteriocin nisin. when atr was induced in wild-type cells, these cells also became resistant to nisin. atr(+) cells also had lower membrane rigidities than control atr(-) cells that had not been subjected to the ac ...200926783167
proinflammatory and phagocytic functions of alveolar macrophages in obesity. 200924973149
potential of chitosan from mucor rouxxi ucp064 as alternative natural compound to inhibit listeria monocytogenes.listeria monocytogenes is widely distributed in nature and the infection listeriosis is recognized as a potential threat for human health because of its mortality rate. the objective of this study was to evaluate the growth profile and chitosan production by mucor rouxxi ucp 064 grown in yam bean (pachyrhizus erosus l. urban) medium. it was also to assess the anti-l. monocytogenes efficacy of the obtained chitosan. higher values of biomass of m. rouxxi (16.9 g.l(-1)) and best yield of chitosan ( ...200924031403
characterization of listeria monocytogenes isolated from a fresh mixed sausage processing line in pelotas-rs by pfge.listeria monocytogenes is a bacterium capable to adhere to the surfaces of equipment and utensils and subsequently form biofilms. it can to persist in the food processing environmental for extended periods of time being able to contaminate the final product. the aim of this study was to trace the contamination route of l. monocytogenes on a fresh mixed sausage processing line, from raw material to the final product. the isolates obtained were characterized by serotyping and molecular typing by p ...200924031402
antiangiogenesis immunotherapy induces epitope spreading to her-2/neu resulting in breast tumor immunoediting.targeting tumors using cancer vaccine therapeutics has several advantages including the induction of long-term immunity, prime boost strategies for additional treatments and reduced side effects compared to conventional chemotherapeutics. however, one problem in targeting tumor antigens directly is that this can lead to antigen loss or immunoediting. we hypothesized that directing the immune response to a normal cell type required for tumor growth and survival could provide a more stable immunot ...200924367160
prediction of proteins putatively involved in the thiol: disulfide redox metabolism of a bacterium (listeria): the cxxc motif as query sequence.thiol:disulfide redox metabolism (tdrm) is a central metabolic network in all living cells. however, numerous proteins with different biochemical functions and several structural domains are involved, making it not trivial to identify and annotate its constituents in sequenced genomes. we developed an uncomplicated approach to solve the problem using existing web-based tools and public databases with the gram-positive bacterium listeria monocytogenes egd-e as a model organism. a pattern search f ...200922430441
synergistic effect of nisin and garlic shoot juice against listeria monocytogenes in milk.the aim of this research was to determine the synergistic effect of nisin and garlic shoot juice (gsj) against listeria monocytogenes atcc 19118 found in whole (3.5%), low (1%) and skim (no fat content) milk. garlic shoot juice (gsj) at concentrations of 2.5%, 5% and 10% revealed strong and similar patterns of antilisterial effect against l. monocytogenes atcc 19118 in all categories of milk. nisin only at concentrations of 62.5, 125, 250 and 500iu/ml displayed a strong antilisterial effect as c ...200826049229
quantitative evaluation of listeria monocytogenes in fresh and processed surubim fish (pseudoplatystoma sp).l. monocytogenes is a foodborne psychrotrophic bacterial pathogen of special importance for minimally processed foods. in this work, it was enumerated in samples of surubim fish by mpn technique. the population of l. monocytogenes was estimated as < 0.012 mpn/cm(2) in fresh and < 0.03 mpn/g in minimally processed fish.200824031260
behaviour of l. monocytogenes in sliced, vacuum-packed mortadella.this study evaluated the growth of naturally occurring l. monocytogenes in sliced, vacuum-packed mortadella samples during storage at 5°c until the expiration date. tukey's test indicated that counts of l. monocytogenes on 0, 10, 20, 30 and 40 days of storage were significantly different (p<0.05), indicating growth during shelf life. in three trials, the mean increase was 1.72 log cycles. vacuum packing and storage under refrigeration were not effective in controlling the growth of l. monocytoge ...200824031257
epidemiological survey of listeria monocytogenes in a gravlax salmon processing line.listeria monocytogenes is a cause of concern to food industries, mainly for those producing ready-to-eat (rte) products. this microorganism can survive processing steps such as curing and cold smoking and is capable of growing under refrigeration temperatures. its presence in rte fish products with extended shelf life may be a risk to the susceptible population. one example of such a product is gravlax salmon; a refrigerated fish product not exposed to listericidal processes and was the subject ...200824031233
molecular analysis of the iap gene of listeria monocytogenes isolated from cheeses in rio grande do sul, brazil.the polymorphic region sequences in the iap gene were analyzed in 25 strains of listeria monocytogenes isolated from cheeses in the state of rio grande do sul, and compared with reference strains. this investigation distinguished two clusters of l. monocytogenes: i (20 strains) and ii (5 strains).200824031198
spontaneous bacterial peritonitis caused by infection with listeria monocytogenes.spontaneous bacterial peritonitis is a severe and life-threatening complication in patients with ascites caused by advanced liver disease. the organisms most commonly involved are coliform bacteria and third-generation cephalosporins are the empiric antibiotics of choice. this is an uncommon case of spontaneous bacterial peritonitis caused by listeria monocytogenes in a female patient with liver cirrhosis from autoimmune hepatitis. she did not improve with ceftriaxone and her course was complica ...200821490863
biotechnological applications of listeria's sophisticated infection strategies.listeria monocytogenes is a gram-positive bacterium that is able to survive both in the environment and to invade and multiply within eukaryotic cells. currently l. monocytogenes represents one of the most well-studied and characterized microorganisms in bacterial pathogenesis. a hallmark of l. monocytogenes virulence is its ability to breach bodily barriers such as the intestinal epithelium, the blood-brain barrier as well as the placental barrier to cause severe systemic disease. curiously, th ...200821261856
listeria monocytogenes meningitis in adults. 200821063320
antimicrobial activities of spice extracts against pathogenic and spoilage bacteria in modified atmosphere packaged fresh pork and vacuum packaged ham slices stored at 4 degrees c.the antimicrobial activity of 14 spice extracts against four common meat spoilage and pathogenic bacteria (listeria monocytogenes, escherichia coli, pseudomonas fluorescens and lactobacillus sake) was screened in cultured media (experiment 1). the results showed that individual extracts of clove, rosemary, cassia bark and liquorice contained strong antimicrobial activity, but the mixture of rosemary and liquorice extracts was the best inhibitor against all four types of microbes. subsequently, m ...200820416570
antimicrobial activity of various extracts of ocimum basilicum l. and observation of the inhibition effect on bacterial cells by use of scanning electron microscopy.the antimicrobial activities of chloroform, acetone and two different concentrations of methanol extracts of ocimum basilicum l. were studied. these extracts were tested in vitro against 10 bacteria and 4 yeasts strains by the disc diffusion method. the results indicated that the methanol extracts of o. basilucum exhibited the antimicrobial activity against tested microorganisms. while the chloroform and acetone extracts had no effect, the methanol extracts showed inhibition zones against strain ...200820161958
[listeria monocytogenes meningitis in children in france].listeriosis is a serious invasive disease which affects mainly pregnant women, newborns and immunocompromised adults.200819268247
[microbiological contamination and antimicrobial activity of cristalised cane sugar on some medically important microorganisms in costa rica].microbiological contamination and antimicrobial activity of cristalised cane sugar on some medically important microorganisms in costa rica. unrefined cristalised cane sugar, obtained after the filtration and evaporation of sugar cane juice, is a nutritional product of traditional consumption in costa rica and other neotropical countries. it has been used in the topic treatment of infected wounds, with satisfactory results even with some antibiotic-ressistant bacteria. we studied the microbiolog ...200819256417
effect of whey protein coating on quality attributes of low-fat, aerobically packaged sausage during refrigerated storage.whey protein-based edible coating was used to reduce oxidative degradation and microbial growth of low-fat sausages (lfss) stored at 4 degrees c for 8 wk, under aerobic package. whey protein coating reduced (p<0.05) thiobarbituric acid-reactive substances (tbars) and peroxide value (pv) formation compared to control sausages. the percent inhibition of tbars and pv for whey protein-coated sausages, compared to the control, was 31.3% and 27.1%, respectively. the ability of the whey protein coating ...200819241536
modeling surface transfer of listeria monocytogenes on salami during slicing.listeria monocytogenes has been implicated in several listeriosis outbreaks linked to the consump tion of presliced ready-to-eat (rte) deli meats, which has drawn considerable attention in regard to possible cross-contamination during slicing operation at retail and food service environments. salami with 15% fat (a moderate l fat content deli item) was used to investigate the transfer of l. monocytogenes between a meat slicer and salami slices and to understand its impact on food safety. a 6-str ...200819241551
effect of electrolyzed water for reduction of foodborne pathogens on lettuce and spinach.the ability of electrolyzed water (ew) to inactivate foodborne pathogens on the surfaces of lettuce and spinach was investigated. lettuce and spinach leaves were inoculated with a cocktail of 3 strains each of escherichia col o157:h7, salmnonella typhimurium, and listeria monocytogenes and treated with acidic electrolyzed water (ac-ew), alkaline electrolyzed water (ak-ew), alkaline electrolyzed water followed by acidic electrolyzed water (sequential treatment, ak-ew + ac-ew), deionized water fol ...200819241556
microbial assessment in school foodservices and recommendations for food safety improvement.this study evaluated microbial food safety in school foodservices. five school foodservices were randomly selected, and samples from water, cooking utensils, tableware, foodservice surroundings, and linen were collected in summer and winter (n=420). tap and drinking water samples were collected, samples of food contact surfaces were collected by swab-kit, and samples for foodservice workers' hands and gloves were prepared by glove juice method. aerobic plate count (apc) and coliform bacterial po ...200819241563
the effects of stress on respiratory disease and transient colonization of turkeys with listeria monocytogenes scott a.listeria monocytogenes contaminates poultry processing plants due to its ubiquitous nature and high resistance to disinfection. the sources of the persistent, biofilm-forming strains that colonize processing plants are unknown. the purpose of this study is to determine if intrinsic colonization of turkeys is a possible source of contamination. male poults were subjected to cold stress from 4-12 days of age; poults were unchallenged or were exposed to an aerosol and oral challenge of either an av ...200819166048
identification and analysis of the osmotolerance associated genes in listeria monocytogenes.listeria monocytogenes, the causative agent of listeriosis, has strong osmotolerance and is able to grow in severe circumstances. many studies of the mechanisms of listerial osmotolerance have been performed. however, there is much which remains unknown. in previous studies we constructed two kinds of mutant in l. monocytogenes egd strain to analyse the mechanisms of osmotolerance in l. monocytogenes by molecular genetic methods. in this paper, we summarized the genetical studies of osmotoleranc ...200819238619
antimicrobial activity of organically modified nano-clays.antimicrobial activity of three kinds of commercially available montmorillonite nano-clays including a naturally occurring one (cloisite na+) and two organically modified ones (cloisite 20a and cloisite 30b) against four representative pathogenic bacteria (two gram-positive ones such as staphylococcus aureus and listeria monocytogenes, and two gram-negative ones such as salmonella typhimurium and e. coli o157:h7) was investigated. antimicrobial activity was found to be dependent on the type of n ...200819198311
recognition of salmonella typhimurium by immobilized phage p22 monolayers.phages are promising alternatives to antibodies as the biorecognition element in a variety of biosensing applications. in this study, a monolayer of bacteriophage p22 whose tailspike proteins specifically recognize salmonella serotypes was covalently bound to glass substrates through a bifunctional cross linker 3-aminopropyltrimethoxysilane. the specific binding of salmonella typhimurium to the phage monolayer was studied by enzyme-linked immunosorbent assay and atomic force microscopy. escheric ...200819461940
current trends in follow-up of trophoblastic function in ruminant species.during the pregnancy of ruminants, different hormones and proteins are secreted by placenta or corpus luteum allowing the follow up of gestation. among them, progesterone (p4) and pregnancy-associated glycoproteins (pag) were proposed as laboratory tools to establish or to confirm pregnancy diagnosis. in last years, pag assay also provided useful information for researchers working in programs focused on the follow up of trophoblastic function. concentrations of pag appeared as altered after the ...200819261972
tnf receptor-associated factor 5 is required for optimal t cell expansion and survival in response to infection.receptors belonging to the tnf-receptor (tnf-r) superfamily include important costimulatory molecules, many of which specifically affect t cell activation. tnf receptor-associated factors (trafs) are recruited to many tnf-r superfamily members and are important modulators of the proximal signaling events that occur at the time of receptor engagement and activation. traf5 has been shown to be a positive regulator of a number of these receptors that are involved in t cell costimulation. however, t ...200819017969
cancer immunotherapy using listeria monocytogenes and listerial virulence factors.our laboratory is interested in how immunogenicity may be modulated in vivo in order to better design more effective immunotherapeutics against cancer. our main approach is to use a facultative intracellular bacterium, listeria monocytogenes, which has the unusual ability to live and grow in the cytoplasm of the cell and is thus an excellent vector for targeting passenger antigens to the major histocompatibility complex (mhc) class i pathway of antigen processing with the generation of authentic ...200819018479
coliforms and prevalence of escherichia coli and foodborne pathogens on minimally processed spinach in two packing plants.minimally processed spinach has been recently associated with outbreaks of foodborne illnesses. this study investigated the effect of commercial minimal processing of spinach on the coliform and escherichia coli counts and the prevalence of e. coli o157:h7, salmonella, shigella spp., and listeria monocytogenes on two types of spinach before and after minimal processing. a total of 1,356 spinach samples (baby spinach, n = 574; savoy spinach, n = 782) were collected daily in two processing plants ...200819244890
inactivation of listeria monocytogenes in raw fruits by enterocin as-48.the purpose of this study was to determine the effect of enterocin as-48 on listeria monocytogenes cect 4032 in fruits and fruit juice. fruits were contaminated with a l. monocytogenes cell suspension, washed with enterocin as-48 (25 microg/ml) or with sterile distilled water as control, and stored at different temperatures (-20, 6, 15, 22 degrees c). washing treatments significantly inhibited or completely inactivated l. monocytogenes in strawberries, raspberries, and blackberries stored at 15 ...200819244899
comparison of antimicrobial resistance in escherichia coli, staphylococcus aureus, and listeria monocytogenes strains isolated from organic and conventional poultry meat.the presence of escherichia coli, staphylococcus aureus, and listeria monocytogenes was determined in 55 samples of organic poultry meat and in 61 samples of conventional poultry meat. a total of 220 e. coli, 192 s. aureus, and 71 l. monocytogenes strains were analyzed by an agar disk diffusion assay for their resistance to ampicillin, cephalothin, chloramphenicol, ciprofloxacin, doxycycline, fosfomycin, gentamicin, nitrofurantoin, streptomycin, and sulfisoxazole (e. coli); chloramphenicol, cipr ...200819244911
analysis of additional virulence genes and virulence gene regions in listeria monocytogenes confirms the epidemiologic relevance of multi-virulence-locus sequence typing.previous molecular subtyping studies have defined four epidemic clones (ecs) of listeria monocytogenes (eci, ecii, eciii, and eciv). partial sequences of eight virulence genes were previously shown to be identical within individual ecs of l. monocytogenes. the present study was conducted to determine if the sequences of other virulence genes and virulence gene regions are also conserved within these ecs. six additional virulence genes--bsh, hly, inlj, ipla1, pgda, and srta--and three additional ...200819244915
assessment of safety, nutritional, and spoilage characteristics of different lagoon grey mullets (liza ramada, liza aurata, and liza saliens).different lagoon grey mullets such as liza ramada (thinlip mullet), liza aurata (golden grey mullet), and liza saliens (leaping grey mullet) were analyzed for their nutritional, microbiological, and safety parameters. the microbiological values never exceeded the lower limits stipulated by the italian higher institute of health. the pathogenic species frequently associated with seafood (salmonella, listeria monocytogenes, vibrio cholerae, vibrio parahaemolyticus, and aeromonas hydrophila) were n ...200819244917
[pleural and ascitic fluid infection by listeria monocytogenes. report of one case].ascitic and pleural fluids infection by listeria monocytogenes is uncommon. the association of spontaneous bacterial peritonitis and empyema caused by this microorganism has been seldom reported. a 61-year-old male with an alcoholic cirrhosis and an upper right lobectomy for a lung cancer, consulted because of an exacerbation of dyspnea, abdominal pain and fever. listeria-monocytogenes was isolated from ascitic and pleural fluids and from blood cultures. he was successfully treated with ampicill ...200819301777
characterization of probiotic carnobacteria isolated from rainbow trout (oncorhynchus mykiss) intestine.to characterize two probiotic carnobacterial isolates, carnobacterium maltaromaticum (b26) and c. divergens (b33), derived from rainbow trout (oncorhynchus mykiss) intestine.200819552776
[encephalomeningitis caused by listeria monocytogenes in patient infected by tbe virus--case report].the epidemiology of listeriosis is constantly changing towards higher incidence. the most endangered group of patients are people with immunodeficiency caused by coexisting diseases. in these cases listeriosis may take a very severe course. in this paper we present a case of a 76 year old female who suffered from encephalomeningitis caused by listeria monocytogenes and additionally was infected by tick borne encephalitis virus and borrelia burgdorferi.200822320051
enhancing the antilisterial effect of lactobacillus curvatus cwbi-b28 in pork meat and cocultures by limiting bacteriocin degradation.this work focused on listeria monocytogenes growth inhibition and growth rebound in raw and cooked pork meat inoculated with lactobacillus curvatus strains. during storage of raw meat homogenates in the presence of the bacteriocin-producing strain lactobacillus curvatus cwbi-b28wt, the listeria monocytogenes cfu count was initially reduced to an undetectable level, but a growth rebound occurred after two weeks, coinciding with loss of 70% of the bacteriocin activity present at the end of week 2. ...200822063576
effect of pork lard content on the chemical, microbiological and sensory properties of a typical fermented meat product (pitina) obtained from alpagota sheep.the aim was to investigate the physicochemical, microbiological and sensory properties of pitina, a typical fermented meat product and evaluate the effect of two levels of pork lard content (low fat, lf, 10% vs. high fat, hf, 30%) on its attributes. hf attained lower ph than lf pitina, which reached lower water activity. lab comprised the major flora with substantial counts of micrococci, enterococci and mould and yeast. gram negative enterobacteria were recovered as coliforms and faecal colifor ...200822063596
inhibition of salmonella sp. listeria monocytogenes and staphylococcus aureus in cooked ham by combining antimicrobials, high hydrostatic pressure and refrigeration.recontamination of ready-to-eat products such as cooked ham during post-processing may be the cause of outbreaks of food-borne disease. the effectiveness of the combination of high pressure processing (hpp) at 600mpa with the natural antimicrobials nisin and potassium lactate has been evaluated in sliced cooked ham spiked with 4logcfu/g of salmonella sp., listeria monocytogenes and staphylococcus aureus after 3-months of storage at 1 and 6°c. in non-hpp sliced cooked ham, the addition of nisin p ...200822062095
challenges to meat safety in the 21st century.the safety of meat has been at the forefront of societal concerns in recent years, and indications exist that challenges to meat safety will continue in the future. major meat safety issues and related challenges include the need to control traditional as well as "new," "emerging," or "evolving" pathogenic microorganisms, which may be of increased virulence and low infectious doses, or of resistance to antibiotics or food related stresses. other microbial pathogen related concerns include cross- ...200822062090
microbial safety of meat in the european union.the two most frequently reported zoonotic diseases in humans in the eu in 2005 were campylobacter and salmonella infections with incidences of 51.6 and 38.2 cases per 100,000 population, respectively. reported human infections caused by yersinia spp., verocytotoxigenic escherichia coli, and listeria monocytogenes had comparably lower incidences of 2.6, 1.2 and 0.3 cases per 100,000 population, respectively. meat and meat products are important sources for these infections but knowledge on exactl ...200822062091
purification and characterization of a bacteriocin produced by leuconostoc mesenteroides e131.leuconostoc mesenteroides e131, isolated from greek traditional fermented sausage, prepared without the addition of starters, produces a bacteriocin which is active against the pathogen listeria monocytogenes. the bacteriocin was purified by 50% ammonium sulphate precipitation, cation exchange, and reverse-phase chromatography. bacteriocin is active at ph values between 4.0 and 9.0 and retains activity after incubation for 1h at 100°c. proteolytic enzymes inactivated the bacteriocin after 1h of ...200822063322
microbial profiles of frozen trimmings and silver sides prepared at indian buffalo meat packing plants.to assess microbiological quality of buffalo meat trimmings (tt=114) and silver sides (ss=41), samples were collected from four different indian meat packing plants. the aim of this study was: (i) to evaluate standard plate count (spc), psychrotrophic count (ptc), enterococcus feacalis count (efc), staphylococcus aureus count (sac) and escherichia coli count (ecc) and the presence of salmonella spp. and listeria monocytogenes; and (ii) also to determine vero toxic e. coli (vtec) by polymerase ch ...200822063348
molecular tracking of listeria monocytogenes in an iberian pig abattoir and processing plant.the environment and products from an iberian pig abattoir and processing plant were sampled to investigate the prevalence and genetic diversity of listeria monocytogenes. the organism was not detected in the pig carcasses prior to processing. fresh and dry-cured pork did show detectable levels, always ranging below 100cfu per gram. a total of 163 l. monocytogenes isolates collected during one year were characterized by pcr-based serotyping and pulsed-field gel electrophoresis (pfge) restriction ...200822062102
[biologic therapy and infections].biologic therapy is an important therapeutic arsenal in rheumatic diseases. anti-tnf therapies affect host defenses against infections, since tnf mediates inflammation and modulates cellular immune responses. cases of tuberculosis have been observed in patients treated with tnf antagonists, mainly due to the presence of latent or "dormant" tuberculosis infection (ltb1). other microorganisms responsible for the infectious complications associated with biologic therapy are generally intracellular ...200821794348
characterization and antibiotic susceptibility of listeria monocytogenes isolated from poultry and red meat in morocco.this study was carried out on 426 samples of raw meats collected from butcheries and supermarkets in casablanca, morocco. the samples were examined for the occurrence of listeria species. strains of listeria monocytogenes were characterized by several biochemical tests and confirmed by polymerase chain reaction (pcr). +¦-hemolytic cultures and nonhemolytic isolates were tested for biochemical properties with the listeria api test. among the 43 listeria species isolates; we identified 10 strains ...200821694879
antilisterial activity of plantaricin ug1 during manufacture of zabady and kareesh cheese: two arabian dairy products.here, plantaricin ug1 was shown to inhibit listeria monocytogenes lmg10470 (l. monocytogenes) cells. the inhibition was not caused by lactic acid produced by the bacteriocin producing strain lactobacillus plantarum ug1 (lact. plantarum). partially purified plantaricin ug1 had a higher antilisterial activity than lact. plantarum cells in both zabady and kareesh cheese samples during their maturation. compared to the antilisterial activity in kareesh cheese, plantaricin ug1 showed a faster effect ...200823675104
salmonella type iii-mediated heterologous antigen delivery: a versatile oral vaccination strategy to induce cellular immunity against infectious agents and tumors.salmonella type iii secretion system (t3ss)-mediated translocation can be used for efficient delivery of heterologous antigens to the cytosol of antigen-presenting cells leading to prominent cd8 t-cell priming in orally immunized mice. the time point and duration of hybrid protein translocation during the salmonella infection cycle can be modulated by employing various type iii carrier molecules. the p60 protein of listeria monocytogenes was used as model antigen to construct chimeric ssph2/p60. ...200817719275
listeriolysin o is an improved protein carrier for lymphoma immunoglobulin idiotype and provides systemic protection against 38c13 lymphoma.follicular lymphoma (fl) is a disease that responds to current treatment regimens; however, patients in general relapse with increasingly refractory disease. idiotype-based vaccines are currently under trial for the treatment of fl. these vaccines comprise the patient's bcr idiotype (id) as the tumor antigen conjugated to the protein carrier keyhole limpet hemocyanin (klh); however, other protein carriers may enhance the immune response to the lymphoma id. in this study we investigated whether a ...200817876582
orally administered lactobacillus plantarum reduces pro-inflammatory interleukin secretion in sera from listeria monocytogenes infected mice.lactic acid bacteria have traditionally been thought to have immunomodulating effects. to verify this property, lactobacillus plantarum was orally administered to mice (5 x 107 colony forming units (c.f.u.)), prior to infection with listeria monocytogenes in order to evaluate the host resistance against an infectious micro-organism and to better define the influence of l. plantarum on such responses. balb/c mice were treated daily with l. plantarum or received pbs (sham-treated mice as controls) ...200817894920
improving live attenuated bacterial carriers for vaccination and therapy.live attenuated bacteria are well established as vaccines. thus, their use as carriers for prophylactic and therapeutic macromolecules is a logical consequence. here we describe several experimental applications of bacteria to carry heterologous macromolecules into the murine host. first, listeria monocytogenes are described that are able to transfer eukaryotic expression plasmids into host cells for gene therapy. high multiplicities of infection are still required for efficient gene transfer an ...200817702649
mast cells initiate early anti-listeria host defences.the gram-positive bacterium listeria monocytogenes (l. m.) is the aetiological agent of listeriosis. the early phase listeriosis is characterized by strong innate host responses that play a major role in bacterial clearance. this is emphasized by the fact that mice deficient in t and b cells have a remarkable ability to control infection. mast cells, among the principal effectors of innate immunity, have largely been studied in the context of hyper-reactive conditions such as allergy and autoimm ...200817714516
simultaneous supratentorial and brainstem abscesses due to listeria monocytogenes.multiple supratentorial abscesses caused by listeria monocytogenes are rare. we report the simultaneous occurrence of multiple supratentorial and brainstem abscesses due to listeria, in a patient under corticotherapy for an exacerbation of ulcerative colitis. mr imaging features before and after successful conservative treatments are depicted. in immunocompromised patients with supratentorial listerial abscesses, the coexistence of brainstem abscedation is exceptional. despite high mortality ass ...200817761284
limitation in the detection of listeria monocytogenes in food in the presence of competing listeria innocua.detectability of listeria monocytogenes at 10(0) cfu per food sample in the presence of listeria innocua using standard microbiological detection was evaluated and compared with the real-time pcr-based method.200817887983
a critical role for phospholipase c in protective immunity conferred by listeriolysin o-deficient listeria monocytogenes.attenuated recombinant listeria monocytogenes (lm) strains are a promising class of vaccine vectors that trigger protective antigen-specific cd8 t cells. listeriolysin o (llo) is an important lm virulence determinant allowing the bacterium to escape from the endocytic vacuole into the cell cytoplasm in phagocytic cells. however in non-phagocytic cells, lm phospholipase c can also mediate cytoplasmic entry. the ability of llo-deficient lm to confer long-term protection to infection is uncertain. ...200817888620
antibacterial activity of a bacteriocin-like substance produced by bacillus sp. p34 that targets the bacterial cell envelope.the objective of this study was to investigate the mode of action of bls p34, a bacteriocin-like substance (bls) produced by a novel bacillus sp. strain p34 isolated from the amazon basin. the effect of the bls was tested against listeria monocytogenes, showing a bactericidal effect at 200 au (activity units) ml(-1), while no inhibition of spore outgrowth of bacillus cereus was observed with a dose of 1,600 au ml(-1). growth of escherichia coli and salmonella enteritidis was inhibited, but only ...200817906937
purification and identification of the pediocin produced by pediococcus acidilactici mm33, a new human intestinal strain.the aim of this study was to purify and identify the bacteriocin produced by pediococcus acidilactici mm33, a strain previously isolated from human gut.200817927747
differential expression of inlb and acta in listeria monocytogenes in selective and nonselective enrichment broths.to investigate the effect of selective and nonselective media on the expression of acta and inlb proteins in listeria monocytogenes.200817927754
listeria monocytogenes as novel carrier system for the development of live vaccines.listeria monocytogenes is a facultative intracellular bacterium that enters a variety of non-professional mammalian cells by triggered phagocytosis ("zipper mechanism") and replicates in the cytosol of the infected host cells. therefore, it is a promising vaccine vector for the presentation of passenger antigens to the mhc class ii and especially class i pathways. here, we review recent progress made in our laboratory on the development of novel attenuated l. monocytogenes carrier strains for th ...200817936682
development of a tripartite vector system for live oral immunization using a gram-negative probiotic carrier.the mucosa represents the primary target site and thus the first barrier for most microbial pathogens. nevertheless, nearly all present-day vaccines are applied by an invasive route, target the systemic immune system, and do not confer efficient mucosal protection. currently, mucosal immunity can only be achieved by the delivery of antigens via the mucosal route. therefore, multiple efforts are under way to develop mucosal vaccines and particularly live oral vaccines as these would confer consid ...200817936683
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