Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| organ-specific regulation of the cd8 t cell response to listeria monocytogenes infection. | the intestinal mucosal cd8 t cell response to infection with listeria monocytogenes was measured using mhc class i tetramers and was compared with the response in peripheral blood, secondary lymphoid tissue, and liver. to assess the vaccination potential of listeria and to analyze responses in c57bl/6 mouse strains, a recombinant listeria expressing ova (rlm-ova) was generated. the response peaked at 9 days postinfection with a much larger fraction of the intestinal mucosa and liver cd8 t cell p ... | 2001 | 11207297 |
| ozone-induced modulation of cell-mediated immune responses in the lungs. | most pulmonary immunotoxicology studies of ambient pollutants have been broadly designed to discern if overall humoral or cell-mediated immunity (cmi) was altered; few have assessed effects on particular aspects of immune function. we hypothesized that effects from ozone (o3) exposure on pulmonary cmi are linked in part to changes in local immune cell capacities to form and/or to interact with immunoregulatory cytokines. rats exposed to 0.1 or 0.3 ppm o3 4 h/day 5 days/week, for 1 or 3 weeks wer ... | 2001 | 11222083 |
| systemic immunity and mucosal immunity are induced against human immunodeficiency virus gag protein in mice by a new hyperattenuated strain of listeria monocytogenes. | vaccines designed to control chronic infections by intracellular agents such as human immunodeficiency virus type 1 (hiv-1) require the induction of cell-mediated immune responses to rid the host of pathogen-infected cells. listeria monocytogenes has characteristics that make it an attractive vaccine vector for use against such infections. here we show that parenteral immunization with a new highly attenuated strain of this organism provided complete protection against systemic and mucosal chall ... | 2001 | 11222702 |
| elicitation of predictable immune responses by using live bacterial vectors. | there is an increasing need for novel vaccines able to stimulate efficient and long-lasting responses, which have also low production costs. to confer protective immunity following vaccination, the adequate type of response should be elicited. vaccines based on attenuated bacterial carriers have contained production and delivery costs, and are able to stimulate more potent immune responses than non-replicating formulations. the improved knowledge on carrier physiology and host response, the avai ... | 2001 | 11222981 |
| microbiological quality of fresh leafy vegetables, salad components and ready-to-eat salads: an evidence of inhibition of listeria monocytogenes in tomatoes. | a total of 116 samples of 11 different fresh vegetables from a local market generally consumed in raw form as well as 12 samples of ready-to-eat green salads procured from three grade 1 and 2 restaurants in mumbai, india were examined for overall microbial quality in terms of bacterial, mold and coliform levels and incidence of pathogens such as listeria and yersinia. standard procedures and media were used for isolation and identification studies. thoroughly washed samples of 26 leafy vegetable ... | 2001 | 11225173 |
| diversity in phagocytic signalling. | 2001 | 11228148 | |
| ultrastructural localization of succinate dehydrogenase in some bacteria, after treatment with lubrol w1. | the localization of succinate dehydrogenase in some gram-negative and gram-positive bacteria (salmonella typhimurium, pseudomonas pseudomallei, pseudomonas aeruginosa and listeria monocytogenes) treated with the surface membrane active agent, lubrol w1, was studied by a cytochemical method combined with electron microscopy. | 2001 | 11229657 |
| from the centers for disease control and prevention. multistate outbreak of listeriosis--united states, 2000. | 2001 | 11236753 | |
| flt3 ligand pretreatment promotes protective immunity to listeria monocytogenes. | flt3 ligand (flt3l) plays a critical role in the proliferation, differentiation and survival of haematopoietic progenitor cells. its potential use in a clinical setting has been suggested. here, we report that mice administered flt3l displayed a nine-fold increase in size of their hepatic non-parenchymal cell population and an approximate 365-fold increase in number of mature dendritic cells within their livers. such mice exhibited an elevated resistance to secondary infections with listeria mon ... | 2001 | 11237427 |
| the tumor recall response of antitumor immunity primed by a live, recombinant listeria monocytogenes vaccine comprises multiple effector mechanisms. | listeria monocytogenes, a facultative intracellular bacterium, can induce a potent antitumor immune response if engineered to express a model tumor antigen also expressed by the tumor cells. the effectiveness of this approach is dependent on l. monocytogenes-induced tumor-specific cd4(+) and cd8(+) t-cells. cd8(+) t-cells may mediate tumor eradication largely through direct ctl activity, but the role of cd4(+) t-cells and other cells of the immune system is less clear. here we investigate their ... | 2001 | 11237558 |
| bactericidal properties of group iia and group v phospholipases a2. | group v phospholipase a(2) (pla(2)) is a recently characterized 14-kda secretory pla(2) of mammalian heart and macrophage-derived cells. group iia pla(2), which is structurally close to group v pla(2), has been shown to kill gram-positive bacteria in vitro and to prevent symptoms of gram-positive infection in vivo. we studied the antibacterial properties of fully active recombinant rat group iia and v pla(2)s. both group iia and v pla(2)s were highly bactericidal against gram-positive bacteria, ... | 2001 | 11238650 |
| intestinal and splenic t cell responses to enteric listeria monocytogenes infection: distinct repertoires of responding cd8 t lymphocytes. | listeria monocytogenes is an intracellular bacterium that causes systemic infections after traversing the intestinal mucosa. clearance of infection and long term protective immunity are mediated by l. monocytogenes-specific cd8 t lymphocytes. in this report, we characterize the murine cd8 t cell response in the lamina propria and intestinal epithelium after enteric l. monocytogenes infection. we find that the frequency of mhc class ia-restricted, l. monocytogenes-specific t cells is approximatel ... | 2001 | 11238655 |
| met, the hgf-sf receptor: another receptor for listeria monocytogenes. | the bacterium listeria monocytogenes invades a variety of cells in vitro and in vivo. two proteins are crucial in this process: internalin, which interacts with e-cadherin, and inlb. the first identified ligand for inlb was gc1qr, which has no cytoplasmic domain. the newly discovered inlb receptor, met, fits with the known inlb-induced signals. | 2001 | 11239771 |
| chemical sympathectomy increases the innate immune response and decreases the specific immune response in the spleen to infection with listeria monocytogenes. | many investigators have shown that ablation of the sympathetic nervous system (sns) with 6-hydroxydopamine (6-ohda) can alter cell-mediated and humoral immune responses to antigenic challenge. fewer studies have examined 6-ohda-induced changes in natural immunity. in this study, we have examined the effect of chemical sympathectomy on the nonspecific and specific phases of the response to infection with listeria monocytogenes. sympathectomy decreased splenic bacterial loads 3 and 5 days post-inf ... | 2001 | 11240011 |
| memory phenotype cd8(+) t cells in il-15 transgenic mice are involved in early protection against a primary infection with listeria monocytogenes. | we recently constructed il-15 transgenic (tg) mice using cdna encoding a secretable isoform of the il-15 precursor protein under the control of an mhc class i promoter. the il-15 tg mice exhibited resistance against a primary infection with listeria monocytogenes. the numbers of memory cd8(+) t cells were markedly increased in the il-15 tg mice following listeria infection accompanied by sustained il-15 production. the increased cd44(+)cd8(+) t cells in the infected il-15 tg mice were not specia ... | 2001 | 11241280 |
| multigenic control of listeria monocytogenes susceptibility in mice. | we have used a novel quantitative trait locus model to study the genetics of survival of f2 progeny of susceptible balb/cbyj and resistant c57bl/6byj mice that have been infected with listeria monocytogenes. this allowed us to map modifiers of l. monocytogenes susceptibility to chromosomes 5 and 13. | 2001 | 11242105 |
| [finding the cause of death in intrauterine death--which examination should be done?]. | the incidence of antepartum fetal death after 22 weeks of gestation is about 0.4% in oslo, norway. screening routines will decide how many cases will remain unexplained. one quarter are diagnosed as sudden intrauterine unexplained death (siud). precise knowledge of the cause of death is needed as a basis for counselling, prevention and treatment. | 2001 | 11242876 |
| survival of listeria monocytogenes during the manufacture and ripening of turkish white cheese. | listeria monocytogenes was enumerated during the manufacture and ripening of turkish white cheese with particular reference to a) pasteurized milk, b) cheese milk after inoculation with l. monocytogenes (0 h), c) after curd formation (2 h), d) curd after pressing (6 h), e) curd after ph was reduced (17 h), f) curd after salting (32 h), and g) cheeses during ripening. cheeses were also examined periodically for total solids, moisture and salt contents, ph values and aerobic plate count. an increa ... | 2001 | 11253643 |
| identification of new genes involved in the virulence of listeria monocytogenes by signature-tagged transposon mutagenesis. | listeria monocytogenes is a gram-positive, facultative intracellular pathogen that can cause severe food-born infections in humans and animals. we have adapted signature-tagged transposon mutagenesis to l. monocytogenes to identify new genes involved in virulence in the murine model of infection. we used transposon tn1545 carried on the integrative vector pat113. forty-eight tagged transposons were constructed and used to generate banks of l. monocytogenes mutants. pools of 48 mutants were assem ... | 2001 | 11254558 |
| lack of expansion of major histocompatibility complex class ib-restricted effector cells following recovery from secondary infection with the intracellular pathogen listeria monocytogenes. | sublethal infection of balb/c mice with the intracellular bacterial pathogen listeria monocytogenes leads to the development of antilisterial immunity with concurrent stimulation of major histocompatibility complex (mhc) class ia- and ib-restricted cd8+ effector t cells. secondary l. monocytogenes infection is followed by an accelerated increase in the number of listeria-specific cd8+ cells and rapid clearance of the bacterium from the murine host. recovery from secondary infection is associated ... | 2001 | 11254585 |
| secretion of listeriolysin by brucella suis inhibits its intramacrophagic replication. | the introduction into brucella suis 1330 of a plasmid allowing the heterologous expression of a hybrid cytolysin containing listeriolysin from listeria monocytogenes, and its export via the escherichia coli hemolysin secretion pathway, resulted in secretion of active listeriolysin monitored by erythrocyte lysis. in contrast to observations with the nonhemolytic control strain, the phagosomes of infected human monocytes containing the hemolytic b. suis were partially disrupted, and this strain fa ... | 2001 | 11254648 |
| bactericidal activities of milk lipids. | the bactericidal capacity of digestion products of bovine milk triglycerides and membrane lipids was tested in vitro using escherichia coli o157:h7, salmonella enteritidis, campylobacter jejuni, listeria monocytogenes, and clostridium perfringens. c10:0 and c12:0 fatty acids and digestion products of sphingolipids appeared to be effective bactericidal agents, whereas digestion products of phosphoglycerides were moderately bactericidal. thus, milk fat sphingolipids and triglycerides, particularly ... | 2001 | 11257052 |
| blocking the receptor for interleukin 10 protects mice from lethal listeriosis. | high doses of listeria monocytogenes overcome the ability of a normal mouse to control the infection, due to massive bacterial replication. treatment with an anti-interleukin 10 (il-10) receptor monoclonal antibody prevented the fatal course of infection with high doses of bacteria. this work shows that blocking the receptor for il-10 may have useful therapeutic applications. | 2001 | 11257056 |
| gram-positive and gram-negative bacteria as carrier systems for dna vaccines. | vaccination by intradermal or intramuscular injection of eukaryotic antigen expression vectors (so-called dna vaccines) elicits strong cellular and humoral immune responses. a novel approach employs attenuated mutant strains of gram-positive and gram-negative intracellular bacteria as carriers for the delivery of dna vaccines. this strategy allows the administration of the dna vaccines via mucosal surfaces and a direct delivery of the plasmid dna to professional antigen presenting cells (apc), s ... | 2001 | 11257384 |
| recombinant attenuated bacteria for the delivery of subunit vaccines. | using attenuated intracellular bacteria as carriers, we have developed two different approaches for the delivery of subunit vaccines encoding heterologous antigens. the first system is based on the direct secretion of the heterologous antigens in gram-negative bacteria via the hemolysin secretion system of escherichia coli into either phagosome or cytosol of infected cells. the second approach is based on the transport of eukaryotic antigen expression vectors by intracellular bacteria like liste ... | 2001 | 11257401 |
| interferon-gamma listericidal action is mediated by novel rab5a functions at the phagosomal environment. | control and clearance of listeria monocytogenes infection is an interferon-gamma-dependent process. the listericidal mechanism of action involves activation of nadph oxidase and inducible nitric-oxide synthase to produce reactive oxygen and nitrogen intermediate radicals, respectively. recently, we have described in a nonpathogenic model of l. monocytogenes (hemolysin negative mutant strain) that the interferon-gamma-inducible gtpase rab5a contributed to listeria destruction in resting macrophag ... | 2001 | 11262414 |
| [listeria arthritis in chronic polyarthritis during low dose prednisolone and methotrexate therapy. case report and review of the literature]. | we report about a patient with polyarticular rheumatoid arthritis taking methotrexat and 5 mg prednisolone who developed in the course of a ra flare a septic arthritis in the right shoulder. listeria monocytogenes could be identified as the causative bacteria. clinically, the listeria-induced septic arthritis could not be differentiated from rheumatoid arthritis; fever was not present. the synovial analysis showed a granulocytic effusion with 19,000 cells/ml; there was no microbiological growth ... | 2001 | 11263013 |
| listing listeria's health risks. | 2001 | 11263089 | |
| preferential localization of effector memory cells in nonlymphoid tissue. | many intracellular pathogens infect a broad range of host tissues, but the importance of t cells for immunity in these sites is unclear because most of our understanding of antimicrobial t cell responses comes from analyses of lymphoid tissue. here, we show that in response to viral or bacterial infection, antigen-specific cd8 t cells migrated to nonlymphoid tissues and were present as long-lived memory cells. strikingly, cd8 memory t cells isolated from nonlymphoid tissues exhibited effector le ... | 2001 | 11264538 |
| [interaction between membrane-damaging toxin of listeria monocytogenes and host immune system]. | 2001 | 11268660 | |
| dietitians can prevent listeriosis. | 2001 | 11269602 | |
| dietary supplementation with conjugated linoleic acid does not alter the resistance of mice to listeria monocytogenes infection. | conjugated linoleic acid (cla) has been used experimentally as a dietary supplement to increase lean body weight and to modulate inflammation in a variety of animal species. in addition, human use of dietary cla as a supplement to regulate body fat has received both scientific and public attention. no reports have been published regarding the effects of dietary cla on antimicrobial resistance. in this study, we provide evidence that feeding cla for up to 4 wk does not alter host defense against ... | 2001 | 11269693 |
| extent of microbial contamination in united states pork retail products. | to determine the extent of microbiological contamination of u.s. pork, 384 samples of retail pork were collected from 24 stores in six cities, including (i) whole-muscle, store-packaged pork; (ii) fresh, store-packaged ground pork and/or pork sausage; (iii) prepackaged ground pork and/or pork sausage; and (iv) whole-muscle, enhanced (injected or marinated; 60% store-packaged, 40% prepackaged) pork. additional samples (n = 120) of freshly ground pork and/or pork sausage were collected from two ho ... | 2001 | 11271763 |
| formulations and processing of yogurt affect the microbial quality of carbonated yogurt. | carbonation, flavor, culture type, ph, and storage time were varied to investigate the effects of these variables and their interactions on the growth of both typical and nontypical yogurt cultures and some contaminating bacteria. two types of yogurt cultures (yc-470 and yc-180) were used as the source of typical yogurt bacteria, streptococcus thermophilus and lactobacillus delbrueckii subsp. bulgaricus. in addition, lactobacillus acidophilus (la-k) and bifidobacterium longum atcc 15707 were add ... | 2001 | 11286405 |
| generation and analysis of mice lacking the chemokine fractalkine. | fractalkine (cx(3)cl1) is the first described chemokine that can exist either as a soluble protein or as a membrane-bound molecule. both forms of fractalkine can mediate adhesion of cells expressing its receptor, cx(3)cr1. this activity, together with its expression on endothelial cells, suggests that fractalkine might mediate adhesion of leukocytes to the endothelium during inflammation. fractalkine is also highly expressed in neurons, and its receptor, cx(3)cr1, is expressed on glial cells. to ... | 2001 | 11287620 |
| a survey of ethnic foods for microbial quality and aflatoxin content. | a range of ethnic foods was examined for their microbiological content in relation to total viable counts (tvc) of aerobic bacteria, counts of presumptive coliforms, yeast and mould counts; presence of salmonella spp., listeria monocytogenes, escherichia coli o157:h7 and campylobacter spp.; total enumeration of clostridium perfringens, staphylococcus aureus and bacillus spp.; identification of moulds and the presence of total aflatoxins. samples, which included cereals, nuts, dried fruits, herbs ... | 2001 | 11288910 |
| control of listeria monocytogenes by bacteriocins and monitoring of bacteriocin-producing lactic acid bacteria by colony hybridization in semi-hard raw milk cheese. | 2001 | 11289262 | |
| cd40 signaling converts a minimally immunogenic antigen into a potent vaccine against the intracellular pathogen listeria monocytogenes. | conventional vaccination strategies have failed for numerous pathogens, and the development of novel approaches to vaccine development is a major public health priority. killed or subunit vaccines represent an attractive approach due to their safety, but they suffer from low immunogenicity and generally require adjuvants. in this study, the possibility of harnessing cd40 signaling for enhancing the immunogenicity of killed vaccines was investigated. intravenous immunization of c57bl/6 mice with ... | 2001 | 11290793 |
| ethanol consumption and the susceptibility of mice to listeria monocytogenes infection. | it is well known that excessive alcohol consumption correlates with increased infectious disease. however, the molecular microbiological and immunological bases for ethanol-induced alterations in host defense are largely unknown. | 2001 | 11290860 |
| antibodies against listerial protein 60 act as an opsonin for phagocytosis of listeria monocytogenes by human dendritic cells. | human-monocyte-derived dendritic cells (modc) are very efficient in the uptake of listeria monocytogenes, a gram-positive bacterium which is an important pathogen in humans and animals causing systemic infections with symptoms such as septicemia and meningitis. in this work, we analyzed the influence of blood plasma on the internalization of l. monocytogenes into human modc and compared the uptake of l. monocytogenes with that of salmonella enterica serovar typhimurium and yersinia enterocolitic ... | 2001 | 11292729 |
| protective cytotoxic t lymphocyte responses induced by dna immunization against immunodominant and subdominant epitopes of listeria monocytogenes are noncompetitive. | taking advantage of the fact that plasmid dna encoding a single cytotoxic t lymphocyte (ctl) epitope can induce ctls, we examined the influence of t-cell responses to dominant epitopes on those to a subdominant epitope derived from listeria monocytogenes. our data suggest that interaction between t cells against dominant and subdominant epitopes does not operate in the generation of the hierarchy. furthermore, we found that a single dominant epitope is sufficient for the induction of protective ... | 2001 | 11292768 |
| rapd- and acta gene-typing of listeria monocytogenes isolates of human listeriosis, the intestinal contents of cows and beef. | seventy-five l. monocytogenes isolates of human listeriosis, the intestinal contents of cows and beef were divided into 5 major clusters, 17 sub-clusters and 28 minor clusters by typing using random amplification of polymorphic dna (rapd). according to their major rapd category, l. monocytogenes isolates serotyped as 1/2b and 4b were distinguished from l. monocytogenes isolates of serovars 1/2a and 1/2c. moreover serovar 4b was distinguished from serovar 1/2b by a difference in the rapd sub-clus ... | 2001 | 11293478 |
| validation of iso method 11290 part 1--detection of listeria monocytogenes in foods. | the european and international standard method for the detection of listeria monocytogenes, described in en iso 11290 part 1: 1997 (international organisation for standardisation, geneva) was validated by order of the european commission (standards, measurement and testing fourth framework programme project smt4-ct96-2098). nineteen laboratories in 14 countries in europe participated in a collaborative trial to determine the performance characteristics of the method, which are intended for publi ... | 2001 | 11294351 |
| influence of modified atmospheric storage, lactic acid, and nacl on survival of sublethally heat-injured listeria monocytogenes. | the effect of package atmosphere on survival of uninjured and sublethally heat-injured listeria monocytogenes, inoculated onto tryptose phosphate agar containing 0.85% lactic acid and 2% nacl (tpalas) was investigated. inoculated tpalas plates were packaged in air, 100% n2 (n2), 30% co2-70% n2 (co2-n2), and vacuum and stored at 4 and 20 degrees c for up to 31 days. recovery of l. monocytogenes from tpalas was influenced by the injury status (i.e., injured and uninjured) of the inoculum, storage ... | 2001 | 11294361 |
| development of a dynamic continuous-discrete-continuous model describing the lag phase of individual bacterial cells. | a previous model for adaptation and growth of individual bacterial cells was not dynamic in the lag phase, and could not be used to perform simulations of growth under non-isothermal conditions. the aim of the present study was to advance this model by adding a continuous adaptation step, prior to the discrete step, to form a continuous-discrete-continuous (cdc) model. | 2001 | 11298236 |
| detection and characterization of a bacteriocin, garviecin l1-5, produced by lactococcus garvieae isolated from raw cow's milk. | the identification of a bacteriocin-producing lactococcal strain isolated from raw cow's milk is reported, along with production conditions, physical and chemical properties, and mode of action of the bacteriocin. methods and | 2001 | 11298239 |
| the combined action of carvacrol and high hydrostatic pressure on listeria monocytogenes scott a. | the aim of the study was to investigate the combined antimicrobial action of the plant-derived volatile carvacrol and high hydrostatic pressure (hhp). | 2001 | 11298243 |
| exogenous peptides enter the endoplasmic reticulum of tap-deficient cells and induce the maturation of nascent mhc class i molecules. | mhc class i molecules assemble within the endoplasmic reticulum (er) in complexes that include beta2-microglobulin (beta(2)m), the transporter associated with antigen processing (tap)and several additional chaperones. release of class i complexes from the er is thought to require the binding of an appropriate endogenous peptide, predominantly delivered from the cytosol to the er by tap. it was recently demonstrated that exogenous synthetic peptide could 'directly' enter the er of intact cells, i ... | 2001 | 11298343 |
| dendritic cells are early cellular targets of listeria monocytogenes after intestinal delivery and are involved in bacterial spread in the host. | we studied the sequence of cellular events leading to the dissemination of listeria monocytogenes from the gut to draining mesenteric lymph nodes (mlns) by confocal microscopy of immunostained tissue sections from a rat ligated ileal loop system. ox-62-positive cells beneath the epithelial lining of peyer's patches (pps) were the first listeria targets identified after intestinal inoculation. these cells had other features typical of dendritic cells (dcs): they were large, pleiomorphic and major ... | 2001 | 11298655 |
| thuricin 7: a novel bacteriocin produced by bacillus thuringiensis bmg1.7, a new strain isolated from soil. | detection and identification of new antagonistic activities towards bacillus cereus and relatives. | 2001 | 11298934 |
| the role of l-carnitine and glycine betaine in the survival and sub-lethal injury of non-growing listeria monocytogenes cells during chilled storage. | to determine the role played by previous growth in the presence of osmolytes on the subsequent survival and sub-lethal injury of l. monocytogenes during long-term chilled storage in a model buffer system. | 2001 | 11298942 |
| personal fortune. would you like cheese with that? | 2001 | 11299990 | |
| isolation and characterization of enterocin se-k4 produced by thermophilic enterococci, enterococcus faecalis k-4. | enterococcus sp. k-4, with a bacteriocin-like activity against e. faecium, was isolated from grass silage in thailand. morphological, physiological, and phylogenetic studies clearly identified strain k-4 as a strain of e. faecalis. strain k-4 produced a maximal amount of bacteriocin at 43-45 degrees c. we purified, for the first time, the bacteriocin produced at high temperature by e. faecalis to homogeneity, using adsorption on cells of the producer strain and reversed-phase liquid chromatograp ... | 2001 | 11302155 |
| evaluation of the safety of recombinant p-selectin glycoprotein ligand-immunoglobulin g fusion protein in experimental models of localized and systemic infection. | p-selectin is a major component in the early interaction between platelets, endothelial cells, and inflammatory cells in the initial phases of the innate immune response. the major ligand for p-selectin is p-selectin glycoprotein ligand-1 (psgl-1) and this ligand is expressed on the surface of monocyte, lymphocyte, and neutrophil membranes. a truncated form of recombinant human p-selectin glycoprotein ligand-1 has been covalently linked to immunoglobulin g (rpsgl-ig) and this fusion peptide func ... | 2001 | 11303727 |
| effect of benzalkonium chloride on viability and energy metabolism in exponential- and stationary-growth-phase cells of listeria monocytogenes. | the difference in killing exponential- and stationary-phase cells of listeria monocytogenes by benzalkonium chloride (bac) was investigated by plate counting and linked to relevant bioenergetic parameters. at a low concentration of bac (8 mg liter(-1)), a similar reduction in viable cell numbers was observed for stationary-phase cells and exponential-phase cells (an approximately 0.22-log unit reduction), although their membrane potential and ph gradient were dissipated. however, at higher conce ... | 2001 | 11307882 |
| thermal inactivation of stationary-phase and salt-adapted listeria monocytogenes during postprocess pasteurization of surimi-based imitation crab meat. | the heat resistance of listeria monocytogenes in surimi-based imitation crab meat was examined after growth to stationary phase or adaptation to 15% nacl. an in-package pasteurization treatment at the cold spot of 71.1 degrees c for 15 s was calculated as adequate to inactivate 5 logs of l. monocytogenes (z-value of 5.8 degrees c). the heat resistance of l. monocytogenes in surimi did not increase after adaptation to salt. | 2001 | 11307883 |
| altering the thermal resistance of foodborne bacterial pathogens with an eggshell membrane waste by-product. | eggshells from egg-breaking operations are a significant waste disposal problem. thus, the development of value-added by-products from this waste would be welcomed by the industry. the ability of extracted eggshell membranes containing, several bacteriolytic enzymes (i.e., lysozyme and beta-n-acetylglucosaminidase) or other membrane components to alter the thermal resistance of gram-positive and gram-negative bacterial pathogens was evaluated. mid-log phase cells of salmonella enteritidis (se), ... | 2001 | 11307884 |
| attachment of bacteria to beef from steam-pasteurized carcasses. | the extent to which a bacterial cocktail containing equal numbers of pseudomonas fragi nctc 10689, listeria monocytogenes bl5/2, salmonella typhimurium lt2, and escherichia coli jm 109 attached to loin surface cuts (7 by 5 cm) derived from steam-pasteurized beef carcasses has been evaluated. the extent of attachment was categorized as loosely attached (removed by rinsing), firmly attached (released by stomaching), and irreversibly bound. no significant difference (p > 0.10) in the attachment of ... | 2001 | 11307885 |
| the effect of growth stage and growth temperature on high hydrostatic pressure inactivation of some psychrotrophic bacteria in milk. | the effect of high hydrostatic pressure on the survival of the psychrotrophic organisms listeria monocytogenes, bacillus cereus, and pseudomonas fluorescens was investigated in ultrahigh-temperature milk. variation in pressure resistance between two strains of each organism were studied. the effect of growth stage (exponential and stationary phase), growth temperature (8 and 30 degrees c) on pressure resistance, and sublethal pressure injury were investigated. exponential-phase cells were signif ... | 2001 | 11307889 |
| listeria species in raw and ready-to-eat foods from restaurants. | from september 1999 to march 2000, meat (pork, beef, and chicken), fish (salmon, hake, and sole), vegetable (lettuce and spinach), and spanish potato omelette samples obtained at restaurants were collected and tested for the occurrence of listeria spp. listeria monocytogenes was isolated from 3 (2.9%) out of 103 studied samples. other species isolated were listeria grayi (13.6%), listeria innocua (1.9%), listeria ivanovii (5.8%), listeria seeligeri (3.9%), and listeria welshimeri (1.9%). listeri ... | 2001 | 11307896 |
| incidence and characterization of listeria spp. from foods available in korea. | a total of 410 domestic korean food samples were analyzed for the presence of listeria spp. by the conventional u.s. department of agriculture protocol, and presumptive strains were identified by morphological, cultural and biochemical tests according to bergey's manual and confirmed by api-listeria kit. among the total 410 food samples, 46 samples (11.2%) were found to be contaminated with listeria species. among the 46 strains of listeria spp. isolates, 8 strains (17.42%) for listeria monocyto ... | 2001 | 11307897 |
| antibiotic resistance among listeria, including listeria monocytogenes, in retail foods. | in the past eight to 10 years, reports of antibiotic resistance in food-borne isolates in many countries have increased, and this work examined the susceptibility of 1001 food isolates of listeria species. | 2001 | 11309061 |
| thermal resistance of wild-type and antibiotic-resistant listeria monocytogenes in meat and potato substrates. | this study aimed to elucidate the relationship, if any, between the acquisition/possession of antibiotic resistance in strains of listeria monocytogenes and the resistance of such strains to heat stress. | 2001 | 11309067 |
| rapid detection of listeria monocytogenes in ham samples using immunomagnetic separation followed by polymerase chain reaction. | to develop a 24-h system for the detection of listeria monocytogenes in ham. | 2001 | 11309074 |
| a glutamate decarboxylase system protects listeria monocytogenes in gastric fluid. | we observed that glutamate greatly enhances the survival of listeria monocytogenes in gastric fluid, a phenomenon that is directly linked to glutamate decarboxylase activity (gad). glutamate-mediated acid tolerance has been associated in other intestinal genera with the gad system, in which glutamate is internalized and converted to gamma-aminobutyrate (consuming an intracellular proton) that is subsequently exchanged for another extracellular glutamate via a membrane-located antiporter. molecul ... | 2001 | 11309128 |
| contribution of mhc class i-dependent immune mechanisms induced by attenuated recombinant salmonella typhimurium secreting superoxide dismutase to protection against murine listeriosis. | a recombinant (r)salmonella typhimurium aroa strain secreting the naturally non-secreted superoxide dismutase (sod) of listeria monocytogenes controls murine listeriosis dependent on 'transporter associated with antigen processing' (tap)-mediated immune mechanisms. tap1-deficient mice (devoid of most cd8 t cells) vaccinated with this rsalmonella sods strain succumbed to lethal l. monocytogenes challenge, whereas c57bl/6 mice were protected by this vaccine. moreover, vaccination of h-2i-abeta-def ... | 2001 | 11312024 |
| characterisation of a listeria monocytogenes mutant deficient in d-arabitol fermentation. | we selected and analysed a tn917-lac listeria monocytogenes mutant deficient in d-arabitol fermentation. comparison of the 310-aa-long translated partial sequence of the disrupted gene with known proteins showed similarity with the phosphotransferase system galactitol-specific enzyme iic component of the alkaliphilic bacillus halodurans (50% identity) and of escherichia coli (36% identity). fermentation of 18 other carbohydrates was unimpaired, suggesting the specificity of this transmembrane pe ... | 2001 | 11316371 |
| comparison of logistic regression and linear regression in modeling percentage data. | percentage is widely used to describe different results in food microbiology, e.g., probability of microbial growth, percent inactivated, and percent of positive samples. four sets of percentage data, percent-growth-positive, germination extent, probability for one cell to grow, and maximum fraction of positive tubes, were obtained from our own experiments and the literature. these data were modeled using linear and logistic regression. five methods were used to compare the goodness of fit of th ... | 2001 | 11319091 |
| morphological and physiological characterization of listeria monocytogenes subjected to high hydrostatic pressure. | high hydrostatic pressure is a new food preservation technology known for its capacity to inactivate spoilage and pathogenic microorganisms. that inactivation is usually assessed by the number of colonies growing on solid media after treatment. under normal conditions the method does not permit recovery of damaged cells and may underestimate the number of cells that will remain viable and grow after a few days in high-pressure-processed foodstuffs. this study investigated the damage inflicted on ... | 2001 | 11319107 |
| comparative genetic characterization of listeria monocytogenes isolates from human and animal listeriosis cases. | listeria monocytogenes isolates from human sporadic and epidemic cases (n=119) and from animal cases (n=76) were characterized by automated ribotyping and pcr-restriction fragment length polymorphism (pcr-rflp) typing of the virulence genes acta and hly. this combination of typing methods differentiated 39 distinctive strains, each reflecting a unique combination of ribotypes, hly and acta alleles. simpson's index of discrimination indicated a high discriminatory ability of ribotyping for both a ... | 2001 | 11320113 |
| pulsenet standardized protocol for subtyping listeria monocytogenes by macrorestriction and pulsed-field gel electrophoresis. | pulsenet is a national network of pubic health and food regulatory laboratories established in the us to detect clusters of foodborne disease and respond quickly to foodborne outbreak investigations. pulsenet laboratories currently subtype escherichia coli o157:h7, non-typhoidal salmonella, and shigella isolates by a highly standardized 1-day pulsed-field gel electrophoresis (pfge), and exchange normalized dna "fingerprint" patterns via the internet. we describe a standardized molecular subtypin ... | 2001 | 11322701 |
| occurrence of listeria species in retail poultry meat and comparison of a cultural/immunoassay for their detection. | the prevalence of listeria spp. on the skin of a hundred fresh chicken carcasses purchased from 20 retail stores in león was investigated using the routine test procedure recommended by the united states department of agriculture (usda). palcam and modified oxford agar (mox) were used for isolation. listeria spp., listeria monocytogenes, l. innocua, l. welshimeri, l. grayi and l. ivanovii were present in 95%, 32%, 66%, 7%, 4% and 2% of the samples, respectively. next, an immunoassay test (lister ... | 2001 | 11322703 |
| diversity of listeria monocytogenes isolates from cold-smoked salmon produced in different smokehouses as assessed by random amplified polymorphic dna analyses. | one hundred and forty-eight listeria monocytogenes isolates originating from vacuum packed cold-smoked salmon produced in 10 different danish smokehouses were compared by random amplified polymorphic dna (rapd) profiling. a total of 16 different reproducible rapd profiles were obtained using a standardised rapd analysis by four primers separately. the grouping of the 148 strains was exactly the same for the four primers used. for a sub-set of 20 strains typed by pulsed field gel electrophoresis ... | 2001 | 11322704 |
| the innate immune response to bacterial flagellin is mediated by toll-like receptor 5. | the innate immune system recognizes pathogen-associated molecular patterns (pamps) that are expressed on infectious agents, but not on the host. toll-like receptors (tlrs) recognize pamps and mediate the production of cytokines necessary for the development of effective immunity. flagellin, a principal component of bacterial flagella, is a virulence factor that is recognized by the innate immune system in organisms as diverse as flies, plants and mammals. here we report that mammalian tlr5 recog ... | 2001 | 11323673 |
| the cd8 response on autopilot. | 2001 | 11323687 | |
| in vitro antibacterial activity of some aliphatic aldehydes from olea europaea l. | in the present paper we report the 'in vitro' activity of eight aliphatic long-chain aldehydes from olive flavor (hexanal, nonanal, (e)-2-hexenal, (e)-2-eptenal, (e)-2-octenal, (e)-2-nonenal, (e)-2-decenal and (e,e)-2,4-decadienal) against a number of standard and freshly isolated bacterial strains that may be causal agents of human intestinal and respiratory tract infections. the saturated aldehydes characterized in the present study do not exhibit significant antibacterial activity, while the ... | 2001 | 11325546 |
| mechanisms underlying antigen-specific cd8+ t cell homeostasis. | 2001 | 11326087 | |
| comparison of sludge and clinical isolates of listeria monocytogenes. | listeria monocytogenes strains isolated in the same geographical area from sewage sludge and from patients presenting with listeriosis were compared. | 2001 | 11328501 |
| automated simultaneous detection of low levels of listeriae and salmonellae in foods. | salmonella spp. and listeria monocytogenes continue to be major pathogens of concern to food processors. however, routine screening of food samples to detect these pathogens is generally labor intensive and costly. automated optical procedures for the detection of salmonellae and listeriae in foods were developed in our laboratory. in the present study we report their adaptation to a simultaneous recovery and detection procedure. milk, shell eggs, fresh and ready-to-eat (rte) meats or raw chicke ... | 2001 | 11246906 |
| effect of different complex carbon sources on growth and bacteriocin synthesis of enterococcus faecium. | different criteria are followed in order to select bacteria to be used in probiotic and symbiotic supplements. a new parameter to choose strains could be fermentation by intestinal bacteria of some complex carbohydrates because they are prebiotics and promote the development of beneficial microorganisms in the intestinal environment. an enterococcus faecium strain, isolated from the crop of a free-range chicken, was assayed in order to determine the utilization of commercial sugars and/or crude ... | 2001 | 11246907 |
| characterization and evaluation of some virulence markers of listeria monocytogenes strains isolated from brazilian cheeses using molecular, biochemical and serotyping techniques. | a total of 207 l. monocytogenes strains isolated from different types of cheeses commercialized in the city of rio de janeiro, brazil, were serotyped and evaluated for their ability to produce beta-haemolysin and lecithinase and to adsorb congo red dye. of the 207 strains, 59.9, 27.5 and 12.6% belonged to serotypes 1/2a, 1/2b and 4b, respectively. in addition, 175 strains of l. monocytogenes produced lecithinase while strains of the other species did not. some of the non-l. monocytogenes strains ... | 2001 | 11246911 |
| arp2/3 complex and actin dynamics are required for actin-based mitochondrial motility in yeast. | the arp2/3 complex is implicated in actin polymerization-driven movement of listeria monocytogenes. here, we find that arp2p and arc15p, two subunits of this complex, show tight, actin-independent association with isolated yeast mitochondria. arp2p colocalizes with mitochondria. consistent with this result, we detect arp2p-dependent formation of actin clouds around mitochondria in intact yeast. cells bearing mutations in arp2 or arc15 genes show decreased velocities of mitochondrial movement, lo ... | 2001 | 11248049 |
| regulating cellular actin assembly. | cellular actin assembly is tightly regulated. the study of pathogen motility has led to the identification of several cellular factors that are critical for controlling this process. pathogens such as listeria require ena/vasp and arp2/3 proteins to translate actin polymerization into movement. recent work has extended these observations and uncovered some similarities and surprising differences in the way cells and pathogens utilize the actin cytoskeleton. | 2001 | 11248549 |
| identification of a pest-like motif in listeriolysin o required for phagosomal escape and for virulence in listeria monocytogenes. | the hly-encoded listeriolysin o (llo) is a major virulence factor secreted by the intracellular pathogen listeria monocytogenes, which plays a crucial role in the escape of bacteria from the phagosomal compartment. here, we identify a putative pest sequence close to the n-terminus of llo and focus on the role of this motif in the biological activities of llo. two llo variants were constructed: a deletion mutant protein, lacking the 19 residues comprising this sequence (residues 32-50), and a rec ... | 2001 | 11251831 |
| the autolysin ami contributes to the adhesion of listeria monocytogenes to eukaryotic cells via its cell wall anchor. | adherence of pathogenic microorganisms to the cell surface is a key event during infection. we have previously reported the characterization of listeria monocytogenes transposon mutants defective in adhesion to eukaryotic cells. one of these mutants had lost the ability to produce ami, a 102 kda autolytic amidase with an n-terminal catalytic domain and a c-terminal cell wall-anchoring domain made up of repeated modules containing the dipeptide gw ('gw modules'). we generated ami null mutations b ... | 2001 | 11251838 |
| thermal inactivation of stationary-phase and acid-adapted escherichia coli o157:h7, salmonella, and listeria monocytogenes in fruit juices. | the heat resistance of stationary-phase and acid-adapted escherichia coli o157:h7, salmonella enterica (serotypes typhimurium, enteritidis, gaminara, rubislaw, and hartford), and listeria monocytogenes was evaluated in single-strength apple. orange, and white grape juices adjusted to ph 3.9. the heat resistance increased significantly (p < 0.05) after acid adaptation. salmonella had an overall lower heat resistance than the other pathogens. acid-adapted e. coli o157:h7 presented the highest heat ... | 2001 | 11252473 |
| heat resistance of an outbreak strain of listeria monocytogenes in hot dog batter. | the heat resistance of a strain of listeria monocytogenes responsible for a listeriosis outbreak in hot dogs was not higher than the heat resistance of other l. monocytogenes strains when tested in tryptic soy broth and in laboratory-prepared hot dog batter. for the thermal death time experiments, the cells were grown to stationary phase or were starved in phosphate-buffered saline, ph 7, for 6 h at 30 degrees c. starvation increased the heat resistance of l. monocytogenes in broth but not in ho ... | 2001 | 11252474 |
| heat resistance of listeria monocytogenes in vegetables: evaluation of blanching processes. | the heat resistance of a listeria monocytogenes composite (serotypes 1/2a, 1/2b, and 4b) was determined in fresh broccoli florets, sweet green peppers, onions, mushrooms, and peas using an end-point procedure in polyester pouches. the heat resistance of l. monocytogenes was higher in peas (d(60 degrees c) = 1.0 min) and mushrooms (d(60 degrees c) = 0.7 min) than in other vegetables tested (d(60 degrees c) in onions = 0.2 min) and was highest when cells were subjected to starvation before the the ... | 2001 | 11252484 |
| heat resistance of listeria monocytogenes. | the heat resistance data on listeria monocytogenes in culture media and foods are summarized. most heat resistance data for foods have been obtained in dairy, meat, poultry, and egg products. limited data have been published on seafood, fruits, and vegetables. the methodologies employed have evolved over time; hence data from earlier experiments are not directly comparable to more recent studies. many factors influence the heat resistance of l. monocytogenes. variation exists among different str ... | 2001 | 11252490 |
| survival of listeria monocytogenes during manufacture, ripening and storage of soft lactic cheese made from raw goat milk. | soft lactic cheeses were manufactured with raw goat milk inoculated with listeria monocytogenes. the physico-chemical and microbiological characteristics of curds and cheeses were determined after each processing step as well as during ripening and refrigerated storage. the fate of listeria monocytogenes was evaluated by enumeration on palcam agar and by a qualitative detection after a double selective enrichment procedure. the results showed that the physico-chemical and microbiological charact ... | 2001 | 11252508 |
| prevalence of glycopeptide and aminoglycoside resistance in enterococcus and listeria spp. in low microbial load diets of neutropenic hospital patients. | low microbial load diets for patients with haematological malignancy were examined for enterococci and listeria using pre-enrichment, enrichment and selective plating. enterococci were highly prevalent and their ecology diverse; 100/211 samples yielded 132 isolates made up of 67 strains distinguishable by pfge. listeria monocytogenes was not found. screening of enterococci for antibiotic resistance showed low level vancomycin resistance (6-12 microg/ml) in six isolates of e. gallinarum and high ... | 2001 | 11252510 |
| use of pfge typing for tracing contamination with listeria monocytogenes in three cold-smoked salmon processing plants. | the sites of listeria monocytogenes contamination in three cold-smoked salmon (salmo salar) processing plants were detected by sampling salmon and the plant's environment and equipment at different production stages. of the 141 samples collected from three processing plants, 59 (42%) were contaminated with l. monocytogenes. the rates of contamination varied as to the plant and the sample source. l. monocytogenes isolates from 17 various contaminated seafood products (fresh, frozen and smoked fis ... | 2001 | 11252511 |
| detection and quantification of the iap gene of listeria monocytogenes and listeria innocua by a new real-time quantitative pcr assay. | a real-time quantitative polymerase chain reaction (pcr) assay for direct detection and enumeration of listeria monocytogenes and listeria innocua was developed and applied to artificially contaminated milk samples. the iap gene present in both species was used as a target for amplification of a 175-bp (l. monocytogenes) and a 309-bp (l. innocua) fragment. to ensure that l. monocytogenes and l. innocua are specifically detectable, tests were carried out using 42 l. monocytogenes strains and 33 l ... | 2001 | 11281324 |
| antimicrobial susceptibility of listeria monocytogenes isolated from meningoencephalitis in sheep. | the antimicrobial susceptibility to different antimicrobial agents of 41 listeria monocytogenes strains isolated from sheep with meningoencephalitis and from feedstuff was tested by both microdilution and disk diffusion methods. both sets of isolates of l. monocytogenes were susceptible to penicillin g, amoxicillin, cephalothin, erythromycin, vancomycin, rifampicin, gentamicin, kanamycin, trimethoprim, sulfisoxazole, chloramphenicol and ciprofloxacin, but resistant to tetracycline and doxycyclin ... | 2001 | 11282267 |
| sensitization of listeria monocytogenes to low ph, organic acids, and osmotic stress by ethanol. | the killing of listeria monocytogenes following exposure to low ph, organic acids, and osmotic stress was enhanced by the addition of 5% (vol/vol) ethanol. at ph 3, for example, the presence of this agent stimulated killing by more than 3 log units in 40 min of exposure. the rate of cell death at ph 3.0 was dependent on the concentration of ethanol. thus, while the presence 10% (vol/vol) ethanol at ph 3.0 stimulated killing by more than 3 log units in just 5 min, addition of 1.25% (vol/vol) etha ... | 2001 | 11282610 |
| enterocin p selectively dissipates the membrane potential of enterococcus faecium t136. | enterocin p is a pediocin-like, broad-spectrum bacteriocin which displays a strong inhibitory activity against listeria monocytogenes. the bacteriocin was purified from the culture supernatant of enterococcus faecium p13, and its molecular mechanism of action against the sensitive strain e. faecium t136 was evaluated. although enterocin p caused significant reduction of the membrane potential (deltapsi) and the intracellular atp pool of the indicator organism, the ph gradient (deltaph) component ... | 2001 | 11282622 |
| characterization of listeria monocytogenes strains involved in invasive and noninvasive listeriosis outbreaks by pcr-based fingerprinting techniques. | a total of 32 listeria monocytogenes strains (16 from a recent outbreak of invasive listeriosis and 16 from two outbreaks of noninvasive listeriosis, all three occurring in italy) were characterized by pcr-ribotyping, arbitrarily primed pcr (ap-pcr), and the recently developed infrequent-restriction-site pcr (irs-pcr). the discriminatory ability of the techniques, first evaluated on 29 unrelated l. monocytogenes food isolates using simpson's index of diversity, was 0.714 for pcr-ribotyping, 0.69 ... | 2001 | 11282635 |
| detection of phospholipase c in nontuberculous mycobacteria and its possible role in hemolytic activity. | phospholipase c plays a key role in the pathogenesis of several bacterial infections, for example, those caused by clostridium perfringens and listeria monocytogenes. previous studies have reported multiple copies of plc genes homologous to pseudomonas aeruginosa plch and plcn genes encoding the hemolytic and nonhemolytic phospholipase c enzymes in the genomes of mycobacterium tuberculosis, m. marinum, m. bovis, and m. ulcerans. in this study we analyzed the possible relationship between phospho ... | 2001 | 11283062 |
| a critical role of t-cell receptor gamma/delta cells in antibacterial protection in mice early in life. | although it is generally assumed that t-cell receptor (tcr) gamma/delta cells participate in protection against intracellular microbial pathogens, their impact remains controversial. in our study, young (14-day-old) mice lacking tcrgamma/delta cells were far more susceptible to listeria monocytogenes than wild-type (wt) mice of the same age. the number of interferon gamma (ifn-gamma) producers responsible for antilisterial resistance was significantly higher among natural killer (nk)1(+) tcrgamm ... | 2001 | 11283853 |
| evaluation of surface contamination and the presence of listeria monocytogenes in fish processing factories. | the main objective of this study was to determine the level of surface contamination in fish processing factories and the presence of listeria in the factory environment and products. another objective was evaluation of the different hygiene-monitoring methods. total aerobic heterotrophic and enterobacteria, yeast and mold samples were collected and atp levels measured in 28 factories. the number of well or adequately washed and disinfected factories was small (2 of 28), in terms of total aerobi ... | 2001 | 11347992 |