Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| physiological damages of listeria monocytogenes treated by high hydrostatic pressure. | high hydrostatic pressure is a new food preservation technology known for its capacity to inactivate spoilage and pathogenic microorganisms. this study investigated the damages inflicted on listeria monocytogenes cells treated by high pressure for 10 min at 400 mpa in ph 5.6 citrate buffer. under these conditions, no cell growth occurred after 48 h on plate count agar. scanning electron microscopy (sem) revealed that cellular morphology was not really affected. measuring propidium iodide (pi) st ... | 2002 | 12382684 |
| listeria monocytogenes--host interaction. | both innate and adaptive immunity against listeria monocytogenes are essential in circumventing or fighting the disease, although there is no clear delineation of the precise role of either in listeriosis. a consistent amount of in vivo experiments have generated a complex picture over the impact of listerial infection on the hosts, and they are shortly reviewed in this paper. | 2002 | 15055261 |
| [study of antibiotic influence on adherence capacity of gram positive and gram negative bacteria to the cellular substrate]. | bacterial adherence to the cellular substrate (skin and mucosa) represents a precondition of infectious pathology. it was demonstrated that bacteria which adhere and form biofilms on catheters and other inert materials used in medicine are resistant to the therapeutic antibiotic concentrations being protected by the biofilm mathrix and generating severe and hard to treat infections. there are only few studies on the influence of antibiotics on the bacterial adhesins synthesis and bacterial adher ... | 2002 | 15085601 |
| bactericidal properties of human and murine groups i, ii, v, x, and xii secreted phospholipases a(2). | group iia secreted phospholipase a(2) (spla2) is known to display potent gram-positive bactericidal activity in vitro and in vivo. we have analyzed the bactericidal activity of the full set of recombinant murine and human groups i, ii, v, x, and xii spla2s on listeria monocytogenes, staphylococcus aureus, and escherichia coli. the rank order potency among human spla2s against gram-positive bacteria is group iia > x > v > xii > iie > ib, iif (for murine spla2s: iia > iid > v > iie > iic, x > ib, ... | 2002 | 11694541 |
| characterization of anti-listeria monocytogenes bacteriocins from enterococcus faecalis, enterococcus faecium, and lactococcus lactis strains isolated from raïb, a moroccan traditional fermented milk. | seventy-four samples of raïb, a moroccan traditional fermented milk, were screened for their anti-listeria monocytogenes activity. nine lactic acid bacteria with antilisterial activity were isolated and identified as lactococcus lactis [4], enterococcus faecium [4], and e. faecalis [1]. antibacterial spectra, determined against 45 target strains, led to the selection of four antibacterial-producing strains, which were further characterized. their anti-microbial agents, inactivated by one or more ... | 2002 | 11727035 |
| antimicrobial and anti-lipase activity of quercetin and its c2-c16 3-o-acyl-esters. | neither quercetin (q), nor 3-o-acylquercetines, up to 100 microg/ml, had any significant activity on selected gram-positive strains (staphylococcus aureus, bacillus subtilis, listeria ivanovi, listeria monocytogenes, listeria serligeri), gram-negative strains (escherichia coli, shigella flexneri, shigella sonnei, salmonella enteritidis, salmonella tiphymurium) and yeasts (candida albicans and candida glabrata). in addition, we confirmed the known anti-hiv activity of q (80% inhibition at 40 micr ... | 2002 | 11741775 |
| cd8(+)-t-cell response to secreted and nonsecreted antigens delivered by recombinant listeria monocytogenes during secondary infection. | understanding how existing antivector immunity impacts live vaccine delivery systems is critical when the same vector system may be used to deliver different antigens. we addressed the impact of antivector immunity, elicited by immunization with attenuated acta-deficient listeria monocytogenes, on the cd8(+)-t-cell response to a well-characterized lymphocytic choriomeningitis virus epitope, np118-126, delivered by infection with recombinant l. monocytogenes. challenges of immune mice with acta-d ... | 2002 | 11748177 |
| stk receptor tyrosine kinase regulates susceptibility to infection with listeria monocytogenes. | we have previously identified the stk receptor tyrosine kinase as a key regulator of macrophage activation and cell-mediated immune responses. here we demonstrate that, although msp activation of stk inhibits no production by macrophages in response to heat-killed listeria monocytogenes, stk-deficient mice exhibit increased susceptibility to infection with listeria. | 2002 | 11748211 |
| complementary adhesion molecules promote neutrophil-kupffer cell interaction and the elimination of bacteria taken up by the liver. | most bacteria that enter the bloodstream are taken up by the liver. previously, we reported that such organisms are initially bound extracellularly and subsequently killed by immigrating neutrophils, not kupffer cells as widely presumed in the literature. rather, the principal functions of kupffer cells demonstrated herein are to clear bacteria from the peripheral blood and to promote accumulation of bactericidal neutrophils at the principal site of microbial deposition in the liver, i.e., the k ... | 2002 | 11751975 |
| safety and immunogenicity in neonatal mice of a hyperattenuated listeria vaccine directed against human immunodeficiency virus. | cd8(+) t cells are a major component of the adaptive response of a host to infections by viruses and other intracellular pathogenic agents. however, because of the intrinsic immaturity of the immune system of neonatal animals, neonates are highly sensitive to a variety of pathogens and may be unable to respond in a protective manner. here we explore whether a hyperattenuated strain of listeria monocytogenes that can be used as a live vaccine vector in adults is safe and able to induce an effecti ... | 2002 | 11752181 |
| hpt, a bacterial homolog of the microsomal glucose- 6-phosphate translocase, mediates rapid intracellular proliferation in listeria. | efficient replication in vivo is essential for a microparasite to colonize its host and the understanding of the molecular mechanisms by which microbial pathogens grow within host tissues can lead to the discovery of novel therapies to treat infection. here we present evidence that the foodborne bacterial pathogen listeria monocytogenes, a facultative intracellular parasite, exploits hexose phosphates (hp) from the host cell as a source of carbon and energy to fuel fast intracellular growth. hp ... | 2002 | 11756655 |
| ampicillin use in infant fever: a systematic review. | to estimate the prevalence of perinatal listeria monocytogenes and enterococcal infections in outpatient febrile infants and to evaluate the need to treat with ampicillin. | 2002 | 11772187 |
| restriction fragment length polymorphisms detected with novel dna probes differentiate among diverse lineages of serogroup 4 listeria monocytogenes and identify four distinct lineages in serotype 4b. | listeria monocytogenes of serotype 4b has been implicated in numerous outbreaks of food-borne listeriosis and in ca. 40% of sporadic cases. strains of this serotype appear to be relatively homogeneous genetically, and molecular markers specific for distinct serotype 4b lineages have not been frequently identified. here we show that dna fragments derived from the putative mannitol permease locus of listeria monocytogenes had an unexpectedly high potential to differentiate among different strains ... | 2002 | 11772609 |
| mycobacterium avium infection of macrophages results in progressive suppression of interleukin-12 production in vitro and in vivo. | interleukin-12 (il-12) has been shown to have an important role in the host defense against mycobacterium avium. we sought to determine if human monocyte-derived macrophages produce il-12 upon m. avium infection. although il-12 can be measured in supernatants of m. avium-infected macrophages at 24, 48, and 72 h following infection, intracellular staining showed that 24 to 48 h after infection, il-12 was synthesized chiefly by uninfected macrophages in the monolayer, suggesting that m. avium infe ... | 2002 | 11781383 |
| dynamin at actin tails. | dynamin, the product of the shibire gene of drosophila, is a gtpase critically required for endocytosis. some studies have suggested a functional link between dynamin and the actin cytoskeleton. this link is of special interest, because there is evidence implicating actin dynamics in endocytosis. here we show that endogenous dynamin 2, as well as green fluorescence protein fusion proteins of both dynamin 1 and 2, is present in actin comets generated by listeria or by type i pip kinase (pipk) ove ... | 2002 | 11782545 |
| listeria monocytogenes rela and hpt mutants are impaired in surface-attached growth and virulence. | we describe here the identification and characterization of two listeria monocytogenes (tn917-ltv3) rela and hpt transposon insertion mutants that were impaired in growth after attachment to a model surface. both mutants were unable to accumulate (p)ppgpp in response to amino acid starvation, whereas the wild-type strain accumulated (p)ppgpp within 30 min of stress induction. the induction of transcription of the rela gene after adhesion was demonstrated, suggesting that the ability to mount a s ... | 2002 | 11790730 |
| overexpression of il-15 in vivo increases antigen-driven memory cd8+ t cells following a microbe exposure. | to elucidate potential roles of il-15 in the maintenance of memory cd8+ t cells, we followed the fate of ag-specific cd8+ t cells directly visualized with mhc class i tetramers coupled with listeriolysin o (llo)(91-99) in il-15 transgenic (tg) mice after listeria monocytogenes infection. the numbers of llo(91-99)-positive memory cd8+ t cells were significantly higher at 3 and 6 wk after infection than those in non-tg mice. the llo(91-99)-positive cd8+ t cells produced ifn-gamma in response to ll ... | 2002 | 11801655 |
| oxidised mannan as a novel adjuvant inducing mucosal iga production. | mannan, oxidatively coupled to recombinant protein antigens, has here been tested as a possible adjuvant for the production of antibody on the mucosa. given intranasally, but not intraperitoneally, mannan markedly enhanced the production of iga, igg1 and igg2a in the serum, and iga locally in the lung and at remote mucosal sites, including tears, vaginal and salivary secretions. oxidative coupling was critical to its action, since neither mannan simply mixed with protein nor mannan-protein conju ... | 2002 | 11803067 |
| act operon control of developmental gene expression in myxococcus xanthus. | cell-bound c-signal guides the building of a fruiting body and triggers the differentiation of myxospores. earlier work has shown that transcription of the csga gene, which encodes the c-signal, is directed by four genes of the act operon. to see how expression of the genes encoding components of the aggregation and sporulation processes depends on c-signaling, mutants with loss-of-function mutations in each of the act genes were investigated. these mutations were found to have no effect on gene ... | 2002 | 11807078 |
| inactivation of escherichia coli o157:h7, salmonella enteritidis, and listeria monocytogenes on apples, oranges, and tomatoes by lactic acid with hydrogen peroxide. | the objective of this study was to develop a practical and effective method for inactivating or substantially reducing escherichia coli o157:h7, salmonella enteritidis, and listeria monocytogenes on apples, oranges, and tomatoes. apples, oranges, and tomatoes were spot-inoculated with five-strain mixtures of e. coli o157:h7, salmonella enteritidis, and l. monocytogenes near the stem end and were submerged in sterile deionized water containing 1.5% lactic acid plus 1.5% hydrogen peroxide for 15 m ... | 2002 | 11808779 |
| incidence and polymerase chain reaction assay of listeria monocytogenes from raw milk in gyeongnam province of korea. | a total of 50 raw milk samples from gyeongnam province of korea were examined for the incidence of listeria monocytogenes between july 1998 and august 1998. l. monocytogenes isolated by biochemical test was confirmed by polymerase chain reaction (pcr) with two sets of primers designed from the invasion-associated protein (iap) gene. after standard pcr with external primers, the amplified dna was confirmed by a second round of pcr with internal primers (nested pcr). both the external and internal ... | 2002 | 11808781 |
| inhibition of listeria monocytogenes by sodium diacetate and sodium lactate on wieners and cooked bratwurst. | the inhibition of listeria monocytogenes by sodium lactate and sodium diacetate was evaluated for wieners containing pork, turkey, and beef and for cooked bratwurst containing beef and pork. both products were supplied by commercial manufacturers. treated products were surface-inoculated with 10(5) cfu of l. monocytogenes per package and vacuum-packed in gas-impermeable pouches. wieners were stored for 60 days at 4.5 degrees c, and bratwurst were stored for 84 days at 3 and 7degrees c. a surface ... | 2002 | 11808782 |
| osmotic dehydration of apple slices with cacl2 and sucrose limits decay caused by penicillium expansum, colletotrichum acutatum, and botrytis cinerea and does not promote listeria monocytogenes or total aerobic population growth. | the interaction of penicillium expansum link, colletotrichum acutatum, and botrytis cinerea pers.:fr. with listeria monocytogenes on osmotically dehydrated apple slices was evaluated. in mineral analyses of the slices, the calcium content of the peel and flesh tissues increased by 4- and 11-fold, respectively, when processed in 2% cacl2. these slices also exhibited less decay by p. expansum, c. acutatum, and b. cinerea. inoculation of slices with p. expansum resulted in a decrease in the ph of t ... | 2002 | 11808790 |
| growth of escherichia coli o157:h7, salmonella typhimurium dt104, and listeria monocytogenes in dark cutting beef at 10 or 22 degrees c. | an experiment was conducted to determine the effects of the dark, firm, and dry (dfd) condition of beef on growth of the foodborne pathogens escherichia coli o157:h7, salmonella typhimurium dt104, and listeria monocytogenes scott a in ground beef. longissimus muscles from a dfd carcass (ph = 6.45) and normal carcass (n; ph = 5.64) were ground and samples obtained (100 and 0% dfd, respectively). equal amounts of the 0 and 100% dfd ground samples were mixed to obtain 50% dfd samples. inoculated 0, ... | 2002 | 11808795 |
| recombinant lema without adjuvant induces extensive expansion of h2-m3-restricted cd8 effectors, which can suppress primary listeriosis in mice. | mice infected with listeria monocytogenes (lm) produce large numbers of h2-m3-restricted cd8 t cells directed against the formylated peptides, f-migwii and f-mivil. to examine responsiveness to these epitopes in the absence of infection, we inoculated mice with recombinant lema (r-lema) containing f-migwii or r-vema (a variant of r-lema containing f-mivil in place of f-migwii) without adjuvant. to monitor responses, we measured peptide-specific cytoplasmic ifn-gamma production ex vivo by freshly ... | 2002 | 11809741 |
| [spontaneous bacterial peritonitis due to listeria monocytogenes]. | 2002 | 11820985 | |
| risk factors for l. monocytogenes contamination of dairy products in switzerland, 1990-1999. | our purpose was to identify the main hazards associated with the spread of listeria monocytogenes in dairy products in switzerland and to determine the changes in predominant serotypes of the isolates, using databases on dairy-processing and environments from the swiss dairy research station during the years 1990-1999. overall, of 76,271 samples collected, 3722 (4.9%) were positive for the presence of l. monocytogenes. cheese-ripening facilities had the highest proportion of positive samples (7. ... | 2002 | 11821137 |
| dysregulation of interleukin-10 and interleukin-12 are involved in the reduced host resistance to listeria monocytogenes infection in alymphoplastic aly mutant mice. | the aly is a unique spontaneous autosomal recessive mutation in mice that causes a systemic defect of lymph nodes and peyer's patches and disorganized splenic and thymic structures with immunodeficiency. our previous study demonstrated that resistance to listeria monocytogenes infection and interferon-gamma (ifn-gamma) production are attenuated in the mutant mice. in this study, we investigated the mechanism of decrease in antilisterial resistance and ifn-gamma production in aly mice. interleuki ... | 2002 | 11821232 |
| enhanced levels of cold shock proteins in listeria monocytogenes lo28 upon exposure to low temperature and high hydrostatic pressure. | listeria monocytogenes is a psychrotrophic food-borne pathogen that is problematic for the food industry because of its ubiquitous distribution in nature and its ability to grow at low temperatures and in the presence of high salt concentrations. here we demonstrate that the process of adaptation to low temperature after cold shock includes elevated levels of cold shock proteins (csps) and that the levels of csps are also elevated after treatment with high hydrostatic pressure (hhp). two-dimensi ... | 2002 | 11823178 |
| expression of acta, ami, inlb, and listeriolysin o in listeria monocytogenes of human and food origin. | expression of proteins involved in the adhesion of listeria monocytogenes to mammalian cells or in the intracellular life cycle of this bacterium, including listeriolysin o (llo), acta, ami, and inlb, was used to compare two populations of l. monocytogenes strains. one of the populations comprised 300 clinical strains, and the other comprised 150 food strains. all strains expressed llo, inlb, and acta. no polymorphism was observed for llo and inlb. ami was detected in 283 of 300 human strains an ... | 2002 | 11823199 |
| listeria monocytogenes lo28: surface physicochemical properties and ability to form biofilms at different temperatures and growth phases. | the surface physicochemical properties of listeria monocytogenes lo28 under different conditions (temperature and growth phase) were determined by use of microelectrophoresis and microbial adhesion to solvents. the effect of these parameters on adhesion and biofilm formation by l. monocytogenes lo28 on hydrophilic (stainless steel) and hydrophobic (polytetrafluoroethylene [ptfe]) surfaces was assessed. the bacterial cells were always negatively charged and possessed hydrophilic surface propertie ... | 2002 | 11823213 |
| frequency of bacteriocin resistance development and associated fitness costs in listeria monocytogenes. | bacteriocin-producing starter cultures have been suggested as natural food preservatives; however, development of resistance in the target organism is a major concern. we investigated the development of resistance in listeria monocytogenes to the two major bacteriocins pediocin pa-1 and nisin a, with a focus on the variations between strains and the influence of environmental conditions. while considerable strain-specific variations in the frequency of resistance development and associated fitne ... | 2002 | 11823216 |
| characterization of glycine betaine porter i from listeria monocytogenes and its roles in salt and chill tolerance. | listeria monocytogenes is a pathogenic bacterium that can grow at low temperatures and elevated osmolarity. the organism survives these stresses by the intracellular accumulation of osmolytes: low-molecular-weight organic compounds which exert a counterbalancing force. the primary osmolyte in l. monocytogenes is glycine betaine, which is accumulated from the environment via two transport systems: glycine betaine porter i, an na(+)-glycine betaine symporter; and glycine betaine porter ii, an atp- ... | 2002 | 11823223 |
| efficient in vivo presentation of listeria monocytogenes- derived cd4 and cd8 t cell epitopes in the absence of ifn-gamma. | ifn-gamma is an essential component of the early listeria monocytogenes-specific immune response, and is also an important regulator of ag processing and presentation. ag presentation is required for the induction and also the effector function of antimicrobial t cells. to evaluate the effect of ifn-gamma on bacterial ag presentation in vivo, macrophages and dendritic cells were separated from l. monocytogenes-infected tissues and analyzed with peptide-specific cd4 and cd8 t cell lines in a sens ... | 2002 | 11823519 |
| cell-mediated immunity induced by recombinant mycobacterium bovis bacille calmette-guérin strains against an intracellular bacterial pathogen: importance of antigen secretion or membrane-targeted antigen display as lipoprotein for vaccine efficacy. | live recombinant vaccines expressing defined pathogen-derived ags represent powerful candidates for future vaccination strategies. in this study, we report on the differential induction of protective cell-mediated immunity elicited by different recombinant mycobacterium bovis bacille calmette-guérin (bcg) strains displaying p60 ag of listeria monocytogenes in secreted, cytosolic, or membrane-attached form for t cell recognition. anti-listerial protection evoked by the membrane-linked p60 lipopro ... | 2002 | 11823521 |
| specific identification of listeria welshimeri and listeria monocytogenes by pcr assays targeting a gene encoding a fibronectin-binding protein. | we have cloned and sequenced a listeria welshimeri dna fragment homologous to the previously described fibronectin-binding protein-encoding gene (fbp) of listeria monocytogenes (p. gilot, y. jossin, and j. content, j. med. microbiol., 49:887-896, 2000). this l. welshimeri dna fragment expresses a 24.8-kda protein that binds to human fibronectin. based on the fbp sequences, we developed novel pcr assays for the identification of l. welshimeri and l. monocytogenes. | 2002 | 11826001 |
| microbial risks in mild hot smoking of fish. | hot smoked fish should fulfill the requirements set up for ready-to-eat foods. the total bacterial count on the raw material is 10(3) to 10(5) cfu per cm2 of skin and 10(2) to 10(9) cfu per gram of intestines. contamination with pathogenic bacteria is very low, mainly with clostridium botulinum, listeria monocytogenes, staphylococcus aureus, and vibrio parahaemolyticus. in the premises of low hygiene, the contamination may increase due to unsanitary procedures, rotation of assigned duties of wor ... | 2002 | 11833636 |
| acid tolerance of gastrointestinal pathogens. | the ability of pathogenic bacteria to survive in the face of host defense systems is intimately linked to virulence. this is exemplified by gastrointestinal pathogens that must survive exposure to extreme acid conditions within the stomach and organic acid conditions within the small intestine. these organisms have evolved complex systems to respond to acid stress, and recent work has revealed new genetic components involved in survival and virulence. here, we review recent work on four gastroin ... | 2002 | 11834369 |
| selection of bacteriocin producer strains of lactic acid bacteria from a dairy environment. | two strains showing bacteriocin production were selected from a total of 206 lactic acid bacteria isolated from samples of milk, milk serum, whey and homemade cheeses in southern cordoba, argentina. this property was detected by means of well diffusion assays. the strains were identified as enterococcus hirae and enterococcus durans. the protein nature of those substances was proved by showing their sensitivity to type iv and xxv proteases, papaine, trypsin, pepsin and k proteinase. the bacterio ... | 2002 | 11837389 |
| bacteriocin-producing lactobacillus sake as starter culture in dry sausages. | one hundred and fifty-two strains of lactobacillus spp and micrococcus spp, isolated from dry sausages, were screened for inhibitory activity. two of the strains assayed of the genus lactobacillus showed bactericidal activity. they were able to inhibit listeria monocytogenes, listeria seeligeri, listeria innocua, lactobacillus alimentarius and lactobacillus bavaricus. the strains of escherichia coli, salmonella bradford and salmonella newlands, staphylococcus aureus, bacillus cereus, pseudomonas ... | 2002 | 11837390 |
| occurrence of yersiniosis and listeriosis in wild boars in japan. | from december 1994 to february 1995, 131 wild boars (sus scrofa leucomysta) living in a mountainous area in japan were examined for yersiniosis and listeriosis. of 131 wild boars, 76 (58%) were males and 55 (42%) were females. four yersinia spp. including y. pseudotuberculosis, y. enterocolitica, y. frederiksenii, and y. aldovei, were isolated from 49 (37%) of 131 wild boars. yersinia pseudotuberculosis was isolated from five (4%) of 131 wild boars. all y. pseudotuberculosis isolates were seroty ... | 2002 | 11838217 |
| characterization of listeria monocytogenes isolates from the meat, poultry and seafood industries by automated ribotyping. | a total of 564 listeria monocytogenes isolates were characterized by automated ribotyping. the samples were taken from equipment, personnel and the environment after cleaning procedures and during food processing, as well as from raw materials and products from six meat, two poultry and five seafood processing plants located in the faroe islands, finland, iceland, norway and sweden. altogether, 25 different ribotypes (rts) were generated. two rts occurred in the samples from all three food secto ... | 2002 | 11843405 |
| colony-blot assay with anti-p60 antibodies as a method for quick identification of listeria in food. | the present study evaluated the ability to isolate listeria from foods, using shortened procedure of sample enrichment followed by immunomagnetic separation or filtration methods, and serological identification of isolated bacteria by colony-blot and western blot methods with anti-p60 antibodies. by these rapid methods, identification of listeria was achieved in much shorter time (40-48 h) than with standard cultivation and biochemical identification procedures. the rapid methods used are easy t ... | 2002 | 11843414 |
| molecular typing techniques to characterize the development of a lactic acid bacteria community on vacuum-packaged beef. | the development of a community of lactic acid bacteria from vacuum-packaged beef was investigated during a 6-week storage trial at 2 degrees c. the lactic acid bacteria population was monitored by using molecular techniques to identify a random sample of isolates at biweekly intervals during the storage trial. the polymerase chain reaction and a randomly amplified polymorphic dna technique were used to identify and distinguish populations of lactic acid bacteria that developed during the storage ... | 2002 | 11843419 |
| passive immunization with convalescent serum, or oral immunization with formalin-killed organisms, does not protect mice against gastrointestinal challenge with listeria monocytogenes. | listeria monocytogenes is an important foodborne pathogen in both humans and animals. in addition, murine listeriosis is a widely used model for studying the molecular pathogenesis of an intracellular pathogen, and the regulation of protective cellular immunity. little attention has been paid to protective immunity against l. monocytogenes in the gastrointestinal tract, where a secretory immune response might prevent attachment of the bacteria to the intestinal epithelium. in this study we found ... | 2002 | 11848130 |
| survival and growth of alkali-stressed listeria monocytogenes on beef frankfurters and thermotolerance in frankfurter exudates. | cells of listeria monocytogenes exposed at 4 degrees c to 1% solutions of two alkaline cleaners or alkali-adapted in tryptose phosphate broth (ph 10.0) at 37 degrees c for 45 min, followed by 4 degrees c for 48 h, were inoculated onto beef frankfurters containing high fat (16 g) and high sodium (550 mg) or low fat (8 g) and low sodium (250 mg) per 57-g serving. frankfurters were surface inoculated (2.0 log10 cfu/g), vacuum packaged, stored at -20, 4, or 12 degrees c, and analyzed for populations ... | 2002 | 11848560 |
| control of listeria monocytogenes with combined antimicrobials after postprocess contamination and extended storage of frankfurters at 4 degrees c in vacuum packages. | contamination of ready-to-eat foods, such as frankfurters, with listeria monocytogenes, is a major concern that needs to be addressed in order to enhance the safety of these products. the objective of this study was to determine the effectiveness of combinations of antimicrobials included in the formulation of frankfurters against l. monocytogenes inoculated (10(3) to 10(4) cfu/cm2) on their surface after peeling and before vacuum packaging. in addition, the antilisterial effect of immersing the ... | 2002 | 11848561 |
| competitive inhibition of listeria monocytogenes in ready-to-eat meat products by lactic acid bacteria. | forty-nine strains of lactic acid bacteria (lab), isolated from commercially available ready-to-eat (rte) meat products, were screened for their ability to inhibit the growth of listeria monocytogenes at refrigeration (5 degrees c) temperatures on agar spot tests. the three most inhibitory strains were identified as pediococcus acidilactici, lactobacillus casei, and lactobacillus paracasei by 16s rdna sequence analysis. their antilisterial activity was quantified in associative cultures in deman ... | 2002 | 11848562 |
| inactivation of foodborne pathogens in milk using dynamic high pressure. | improving the microbiological safety of perishable foods is currently a major preoccupation in the food industry. the aim of this study was to investigate the inactivation of three major food pathogens (listeria monocytogenes [lsd 105-1], escherichia coli o157:h7 [atcc 35150], and salmonella enterica serotype enteritidis atcc [13047]) by dynamic high pressure (dhp) in order to evaluate its potential as a new alternative for the cold pasteurization of milk. the effectiveness of dhp treatment agai ... | 2002 | 11848566 |
| characterization of an antibacterial peptide produced by brevibacterium linens. | the aim of this research was to investigate the antimicrobial activity produced by brevibacterium linens atcc 9175. | 2002 | 11849329 |
| survival of listeria monocytogenes in commercial food-processing equipment cleaning solutions and subsequent sensitivity to sanitizers and heat. | to determine the ability of listeria monocytogenes to survive exposure to commercial food-processing equipment cleaning solutions and subsequent treatment with sanitizers or heat. | 2002 | 11849330 |
| evaluation of the international phage typing set and some experimental phages for typing of listeria monocytogenes from poultry in spain. | the validity of the international phage set and 13 experimental phages for subtyping listeria monocytogenes strains isolated from poultry in spain was investigated. | 2002 | 11849332 |
| microbial analysis of malaysian tempeh, and characterization of two bacteriocins produced by isolates of enterococcus faecium. | isolation of bacteriocinogenic lactic acid bacteria (lab) from the malaysian mould-fermented product tempeh and characterization of the produced bacteriocin(s). | 2002 | 11849339 |
| mild heat treatment of lettuce enhances growth of listeria monocytogenes during subsequent storage at 5 degrees c or 15 degrees c. | the objective of this study was to determine the influence of mild heat treatment, storage temperature and storage time on the survival and growth of listeria monocytogenes inoculated onto cut iceberg lettuce leaves. | 2002 | 11849355 |
| enhanced inactivation of listeria monocytogenes by nisin in the presence of ethanol. | the effect of combinations of nisin and ethanol on the survival of listeria monocytogenes was investigated. | 2002 | 11849486 |
| bacteriocin production by spray-dried lactic acid bacteria. | cell survival and antagonistic activity against listeria innocua, listeria monocytogenes and staphylococcus aureus were investigated after spray-drying three bacteriocin-producing strains of lactic acid bacteria: carnobacterium divergens, lactobacillus salivarius and lactobacillus sakei. | 2002 | 11849498 |
| formation of d-alanyl-lipoteichoic acid is required for adhesion and virulence of listeria monocytogenes. | the dlt operon of gram-positive bacteria comprises four genes (dlta, dltb, dltc and dltd) that catalyse the incorporation of d-alanine residues into the cell wall-associated lipoteichoic acids (ltas). in this work, we characterized the dlt operon of listeria monocytogenes and constructed a d-ala-deficient lta mutant by inactivating the first gene (dlta) of this operon. the dlta- mutant did not show any morphological alterations and its growth rate was similar to that of the wild-type strain. how ... | 2002 | 11849532 |
| essential role of interleukin-12 (il-12) and il-18 for gamma interferon production induced by listeriolysin o in mouse spleen cells. | the mechanism of gamma interferon (ifn-gamma) production induced by listeriolysin o (llo), a cytolytic virulence factor of listeria monocytogenes, was analyzed with special reference to the involvement of macrophage-derived cytokines in spleen cells of mice. llo purified from the culture supernatant of l. monocytogenes was capable of inducing a high level of ifn-gamma when its cytolytic activity was blocked by cholesterol treatment. the ifn-gamma-inducing ability of llo was not dependent on poss ... | 2002 | 11854182 |
| intracellular induction of listeria monocytogenes acta expression. | following entry into the host cytosol, the bacterial pathogen listeria monocytogenes dramatically increases the expression of several key virulence factors. the expression of acta, whose protein product is required for l. monocytogenes actin-based intracellular motility, is increased by more than 200-fold in cytosolic bacteria in comparison to broth-grown cultures. two distinct promoter elements have been reported to regulate acta expression. one promoter is located immediately upstream of acta ... | 2002 | 11854187 |
| dissociated linkage of cytokine-inducing activity and cytotoxicity to different domains of listeriolysin o from listeria monocytogenes. | listeriolysin o (llo), a cholesterol-binding cytolysin of listeria monocytogenes, exhibits cytokine-inducing and cytolytic activities. because the cytolytic activity was abolished by cholesterol treatment but the cytokine-inducing activity was not, these activities appeared to be linked to different domains of the llo molecule. in this study, we constructed recombinant full-length llo (rllo529) and various truncated derivatives and examined their cytolytic, cholesterol-binding, and gamma interfe ... | 2002 | 11854218 |
| the sortase srta of listeria monocytogenes is involved in processing of internalin and in virulence. | listeria monocytogenes is an intracellular gram-positive human pathogen that invades eucaryotic cells. among the surface-exposed proteins playing a role in this invasive process, internalin belongs to the family of lpxtg proteins, which are known to be covalently linked to the bacterial cell wall in gram-positive bacteria. recently, it has been shown in staphylococcus aureus that the covalent anchoring of protein a, a typical lpxtg protein, is due to a cysteine protease, named sortase, required ... | 2002 | 11854224 |
| polymerase chain reaction for detection of listeria monocytogenes. | 2002 | 11692870 | |
| chemical sympathectomy alters numbers of splenic and peritoneal leukocytes. | sympathectomy of balb/c mice that were injected with either listeria monocytogenes or saline did not affect the total number of splenic leukocytes measured 1-3 days after injection, but sympathectomy did increase the percentages of neutrophils in the spleens of both infected and uninfected mice. by contrast, sympathectomy was associated with increased numbers of peritoneal exudate cells (pec) and peritoneal macrophages in both groups of mice. sympathectomy did not affect tumor necrosis factor-al ... | 2002 | 11846441 |
| hiv-1 infection of primary effusion lymphoma cell line triggers kaposi's sarcoma-associated herpesvirus (kshv) reactivation. | kaposi's sarcoma-associated herpesvirus (kshv) is a gammaherpesvirus etiologically linked to primary effusion lymphoma (pel), to a subset of multicentric castleman's disease and to kaposi's sarcoma (ks), the most common neoplasm associated with aids. among kshv-infected individuals, the risk of ks is much higher in those with human immunodeficiency-1 (hiv-1) infection than among those with other types of immunosuppression, suggesting a direct action of hiv-1 on kshv replication. we show in our r ... | 2002 | 11857356 |
| viability of a five-strain mixture of listeria monocytogenes in vacuum-sealed packages of frankfurters, commercially prepared with and without 2.0 or 3.0% added potassium lactate, during extended storage at 4 and 100 degrees c. | the viability of listeria monocytogenes was monitored on frankfurters containing added potassium lactate that were obtained directly from a commercial manufacturer. eight links (ca. 56 g each) were transferred aseptically from the original vacuum-sealed bulk packages into nylon-polyethylene bags. each bag then received a 4-ml portion of a five-strain mixture of the pathogen. frankfurters containing 2.0 or 3.0% potassium lactate were evaluated using 20 cfu per package, and frankfurters containing ... | 2002 | 11858193 |
| serpin 2a is induced in activated macrophages and conjugates to a ubiquitin homolog. | after i.p. infection of mice with the intracellular bacterium mycobacterium bovis bacillus calmette-guérin, macrophages recovered from the peritoneal cavity display classical signs of immune activation. we have identified a member of the serine protease inhibitor (serpin) family which is highly induced in macrophages during bacillus calmette-guérin infection. serpin 2a (spi2a) expression is also induced in macrophages in vivo during infection with salmonella typhimurium and listeria monocytogene ... | 2002 | 11859133 |
| opportunistic infections after renal transplantation. | opportunistic infection is a serious clinical complication in patients receiving immunosuppressive therapy after kidney transplantation. this article deals with some of the possible infectious agents that were recently encountered at our transplantation centre in düsseldorf, germany. opportunistic organsims such as human herpesviruses 6-8, polyomavirus, parvovirus b19, varicella zoster virus, nocardia and listeria monocytogenes are rare but severe complications that are presented in this overvie ... | 2002 | 11859257 |
| initial characterization of the streptococcus gordonii htpx gene. | examination of the streptococcus gordonii chromosomal region, which lies immediately upstream of the glucosyltransferase positive regulatory determinant rgg, revealed two open reading frames. based on nucleotide sequences, these genes were similar to the listeria monocytogenes lema gene, which is involved in antigen presentation, and the escherichia coli htpx heat shock gene, which has an unknown function. northern hybridization analysis indicated that s. gordonii lema and htpx genes were associ ... | 2002 | 11860552 |
| listeria monocytogenes: clinical and experimental update. | listeria monocytogenes, a small gram-positive bacillus, causes sepsis and meningitis in immunocompromised patients and a devastating maternal/fetal infection in pregnant women. recent outbreaks demonstrated that l. monocytogenes can cause gastroenteritis in otherwise healthy individuals and more severe invasive disease in immunocompromised patients. centralized processing in the food industry may be the cause of these large-scale listeriosis outbreaks. the mouse model of listeriosis, which was d ... | 2002 | 11865436 |
| automated measurements of antilisterial activities of lactate and diacetate in ready-to-eat meat. | standard procedures to enumerate listeria organisms rely on plating food samples on selective agar media. the procedures are labor-intensive, and because of the limited sensitivity, pre-enrichment step is required for the detection of low numbers of the pathogen. in the present study, an automated rapid optic procedure and the standard procedure were used to determine the behavior of the pathogen in ready-to-eat (rte) meat and to test the effect of antilisterial agents. listeria monocytogenes st ... | 2002 | 11869796 |
| bacteriological characteristics of dressed young pigeon (squabs) columba livia domesticus. | a total of 50 frozen squabs carcasses were collected from different retail markets in cairo and giza governorates. the collected samples were examined bacteriologically. the aerobic plate count, the enterobacteriaceae and the staphylococcus count were 6.6 x 10(5), 6.3 x 10(2) and 1.4 x 10(3) cfu./gram, respectively. the results revealed no positive samples for salmonella yersinia entercolitica, listeria monocytogenes and campylobacter jejuni. staphylococcus aureus was isolated from 2% of samples ... | 2002 | 11890056 |
| molecular and cellular basis of the infection by listeria monocytogenes: an overview. | this review rather than covering the whole field, intends to highlight the particularly interesting properties of some proteins involved in the infection by listeria monocytogenes and the general interest in some of the approaches used to analyze the molecular and cellular basis of the infection. after an introduction to the bacterium and to the disease, a description of the infection at the cellular level will be given. the specific features of the pore-forming toxin listeriolysin o, as a prote ... | 2002 | 11890537 |
| delivery of protein antigens and dna by attenuated intracellular bacteria. | on the basis of attenuated intracellular bacteria, we have developed two delivery systems for either heterologous proteins or dna vaccine vectors. the first system utilizes attenuated strains of gram-negative bacteria which are engineered to secrete heterologous antigens via the alpha-hemolysin secretion system (type i) of escherichia coli. the second system is based on attenuated suicide strains of listeria monocytogenes, which are used for the direct delivery of eukaryotic antigen expression v ... | 2002 | 11890559 |
| involvement of receptor-interacting protein 2 in innate and adaptive immune responses. | host defences to microorganisms rely on a coordinated interplay between the innate and adaptive responses of immunity. infection with intracellular bacteria triggers an immediate innate response requiring macrophages, neutrophils and natural killer cells, whereas subsequent activation of an adaptive response through development of t-helper subtype 1 cells (th1) proceeds during persistent infection. to understand the physiological role of receptor-interacting protein 2 (rip2), also known as rick ... | 2002 | 11894097 |
| rick/rip2/cardiak mediates signalling for receptors of the innate and adaptive immune systems. | the immune system consists of two evolutionarily different but closely related responses, innate immunity and adaptive immunity. each of these responses has characteristic receptors-toll-like receptors (tlrs) for innate immunity and antigen-specific receptors for adaptive immunity. here we show that the caspase recruitment domain (card)-containing serine/threonine kinase rip2 (also known as rick, cardiak, cck and ripk2) transduces signals from receptors of both immune responses. rip2 was recruit ... | 2002 | 11894098 |
| a listeriosis patient infected with two different listeria monocytogenes strains. | normally, only one isolate of listeria monocytogenes from a case of listeriosis is subjected to characterization. here we show that two isolates from different sites of the body were not the same strain. such a phenomenon may not have any clinical relevance, although it may confuse the epidemiologist trying to match infection source with infection target. | 2002 | 11895084 |
| preexisting inflammation due to mycobacterium bovis bcg infection differentially modulates t-cell priming against a replicating or nonreplicating immunogen. | induction of t-cell memory by vaccination ensures long-term protection against pathogens. we determined whether on-going inflammatory responses during vaccination influenced t-cell priming. a preexposure of mice to mycobacterium bovis bcg impaired their subsequent ability to prime t cells against listeria monocytogenes. this was characterized by a decrease in l. monocytogenes-specific gamma interferon (ifn-gamma)-secreting cd4(+) and cd8(+) t cells. the intensity of t-cell priming towards l. mon ... | 2002 | 11895959 |
| involvement of phop-phos homologs in enterococcus faecalis virulence. | eleven phop-phos homolog pairs were identified by searching the enterococcus faecalis v583 genome sequence database at the institute for genomic research with the bacillus subtilis phop-phos sequences. each pair appears to be a potential two-component system composed of a response regulator and a sensor kinase. seven of the homologs were disrupted in e. faecalis strain og1rf. tx10293, a mutant disrupted in one of these genes (etar, the first gene of the gene pair designated etars), showed delaye ... | 2002 | 11895963 |
| distinct protein patterns associated with listeria monocytogenes inla- or inlb-phagosomes. | internalization of listeria monocytogenes into non-phagocytic cells is mediated by the interactions between the two bacterial invasion proteins inla (internalin) and inlb and their cellular surface receptors e-cadherin and c-met. to get an insight into all the cellular components necessary for uptake and early intracellular life, we undertook a global proteomic characterization of the early listerial phagosome in the human epithelial cell line lovo. first, we proceeded to an immunocytochemical c ... | 2002 | 11896766 |
| early intracellular events during internalization of listeria monocytogenes by j774 cells. | the gram-positive bacillus listeria monocytogenes gains entry into host cells through a phagosome membrane that forms around entering bacteria. during the early stages of internalization the invading bacteria appear to modify the protein composition of the forming phagosome membrane in j774 cells. mhc class ii molecules on the cell surface and exposed surface molecules available for biotinylation are excluded from the bacteria-host cell membrane interface and from the forming phagosome. this exc ... | 2002 | 11897803 |
| survival and growth of listeria monocytogenes and escherichia coli o157:h7 in ready-to-eat iceberg lettuce washed in warm chlorinated water. | cut iceberg lettuce inoculated with escherichia coli o157:h7 and listeria monocytogenes before and after washing for 3 min in cold (4 degrees c) and warm (47 degrees c) water containing 100 mg/liter total chlorine was stored at i and 10 degrees c in oxygen-permeable film packages (6,000 to 8,000 cc/m2/24 h). cold chlorinated water was detrimental to the survival of e. coli o157: h7 and l. monocytogenes at both storage temperatures. in contrast, washing in warm chlorinated water favored the growt ... | 2002 | 11899043 |
| control of natural microbial flora and listeria monocytogenes in vacuum-packaged trout at 4 and 10 degrees c using irradiation. | the effect of gamma irradiation on the natural microflora of whole salted vacuum-packaged trout at 4 and 10 degrees c was studied. in addition, the effectiveness of gamma irradiation in controlling listeria monocytogenes inoculated into trout was investigated. irradiation at doses of 0.5 and 2 kgy affected populations of bacteria, namely, pseudomonas spp., brochothrix thermosfacta, lactic acid bacteria, h2s-producing bacteria typical of shewanella putrefaciens, and enterobacteriaceae, at both 4 ... | 2002 | 11899050 |
| laboratory-scale preparation of soft cheese artificially contaminated with low levels of escherichia coli o157, listeria monocytogenes, and salmonella enterica serovars typhimurium, enteritidis, and dublin. | the production of cheese with incurred low levels of pathogenic microorganisms stressed by the production process was the aim of the study. a standard protocol for the preparation of artificially contaminated soft cheese on a laboratory scale was developed. milk for cheese preparation was artificially contaminated with pathogenic target microorganisms at low levels, between 1 and 10 cfu/ml. two strains of escherichia coli oi157:h7, two strains of listeria monocytogenes, and three salmonella spp. ... | 2002 | 11899950 |
| recovery of listeria monocytogenes from vacuum-sealed packages of frankfurters: comparison of the u.s. department of agriculture (usda) food safety and inspection service product composite enrichment method, the usda agricultural research service (ars) product composite rinse method, and the usda-ars package rinse method. | this study compared three methods for the recovery of listeria monocytogenes from commercially prepared and vacuum-packaged frankfurters that were inoculated with a five-strain mixture of this pathogen at averages of 22 and 20,133 cfu per package over three trials. the presence and levels of the pathogen were determined by (i) the u.s. department of agriculture (usda) food safety and inspection service (fsis) product composite enrichment method, involving the selective enrichment of a 25-g compo ... | 2002 | 11899951 |
| listeriolysin o: a genuine cytolysin optimized for an intracellular parasite. | cholesterol-dependent cytolysins (cdcs)* are produced by a large number of pathogenic gram-positive bacteria. a member of this family, listeriolysin o (llo), is produced by the intracellular pathogen listeria monocytogenes. a unique feature of llo is its low optimal ph activity (approximately 6) which permits escape of the bacterium from the phagosome into the host cell cytosol without damaging the plasma membrane of the infected cell. in a recent study (glomski et al., 2002, this issue), portno ... | 2002 | 11901162 |
| the listeria monocytogenes hemolysin has an acidic ph optimum to compartmentalize activity and prevent damage to infected host cells. | listeria monocytogenes is a facultative intracellular bacterial pathogen that escapes from a phagosome and grows in the host cell cytosol. the pore-forming cholesterol-dependent cytolysin, listeriolysin o (llo), mediates bacterial escape from vesicles and is approximately 10-fold more active at an acidic than neutral ph. by swapping dissimilar residues from a ph-insensitive orthologue, perfringolysin o (pfo), we identified leucine 461 as unique to pathogenic listeria and responsible for the acid ... | 2002 | 11901168 |
| [persistent vegetative state after meningitis due to listeria monocytogenes]. | 2002 | 11904086 | |
| wild-type intracellular bacteria deliver dna into mammalian cells. | gene transfer in vitro from intracellular bacteria to mammalian phagocytic and non-phagocytic cells and in vivo in mice has been reported. the bacteria used as dna delivery vectors were engineered to lyze upon entry in the cell due to impaired cell wall synthesis for shigella flexneri and invasive escherichia coli, or production of a phage lysin for listeria mono- cytogenes. in vivo gene transfer was obtained with attenuated salmonella typhimurium and resulted in stimulation of mucosal immunity. ... | 2002 | 11906454 |
| oxidised mannan-listeriolysin o conjugates induce th1/th2 cytokine responses after intranasal immunisation. | clearance of infectious organisms does not always require polarised th1 or th2 responses and it may be advantageous for both th1 and th2 responses to be elicited for effective protection against an invading pathogen. it was the aim of this study to investigate oxidised mannan as a possible th1/th2 adjuvant. oxidised mannan was conjugated to two candidate antigens and delivered intranasally to mice. immunisation with the oxidised conjugate resulted in significant antigen specific proliferative re ... | 2002 | 11906778 |
| the ifn-inducible golgi- and endoplasmic reticulum- associated 47-kda gtpase iigp is transiently expressed during listeriosis. | members of the 47-kda gtpase family are implicated in an ifn-gamma-induced, as yet unclear, mechanism that confers innate resistance against infection with intracellular pathogens. overt immunological parameters are apparently uncompromised in mice deficient for individual members and the prototype of this family, igtp, localizes to the endoplasmic reticulum. this suggests that these gtpases are involved in intracellular defense. we analyzed the expression of the 47-kda gtpase cognate, iigp, in ... | 2002 | 11907101 |
| correlation of long-range membrane order with temperature-dependent growth characteristics of parent and a cold-sensitive, branched-chain-fatty-acid-deficient mutant of listeria monocytogenes. | listeria monocytogenes is a food-borne, pathogenic, psychrotolerant bacterium that grows at refrigeration temperatures. long-range membrane order of the parent (10403s) and of a cold-sensitive mutant ( cld-1) deficient in odd-numbered, branched-chain fatty acids was measured using the width of the central line of spectra of an electron paramagnetic resonance probe, 4,4-dimethyl-2-heptyl-2-hexyloxazolidine- n-oxyl (7n14), that locates deep in the hydrocarbon region of the membranes. the line widt ... | 2002 | 11907677 |
| growth, morphology and surface properties of listeria monocytogenes scott a and lo28 under saline and acid environments. | the effect of salt and acid on the growth and surface properties of two strains of listeria monocytogenes was investigated. | 2002 | 11872133 |
| impaired bactericidal activity and host resistance to listeria monocytogenes and borrelia burgdorferi in rats administered an acute oral regimen of ethanol. | a rat model was used to examine how ethanol ingestion may interfere with antimicrobial immunity both in vitro and in vivo. nonimmune long-evans rats were given a short-course treatment orally with excessive amounts of ethanol. their spleens were removed at the time of sacrifice, and separate spleen cell suspensions were prepared and tested in vitro for their ability to kill two bacterial pathogens, listeria monocytogenes and borrelia burgdorferi. after the bacteria were mixed separately with var ... | 2002 | 11874864 |
| relevance of dietary lipids as modulators of immune functions in cells infected with listeria monocytogenes. | nutritional status may have significant importance for the immune system, and particularly, unsaturated fatty acids may serve as modulators of immune functions. clinical and epidemiological studies have demonstrated that fatty acids are involved in the reduction of the inflammatory processes that occur in diseases characterized by an overactivation of the immune system. at the same time, an increase in susceptibility to infection has also been reported. the importance of immune system modulation ... | 2002 | 11874877 |
| sodium bicarbonate enhances the severity of infection in neutropenic mice orally inoculated with listeria monocytogenes egd. | epidemiological studies have suggested an association between antacid therapy and development of listeriosis in humans. in this study we used a neutropenic mouse model to demonstrate that oral administration of sodium bicarbonate shortly before intragastric (i.g.) inoculation with listeria monocytogenes egd (serotype 1/2a) significantly increased the severity of the resulting systemic infection. an explanation for this observation is provided by evidence that l. monocytogenes egd is rapidly inac ... | 2002 | 11874896 |
| the origins of stillbirth: infectious diseases. | this article reviews the literature on infectious diseases as a cause of stillbirth. identifying a specific infection as a cause of stillbirth is limited by many obstacles. nevertheless, "good faith" efforts estimate that approximately 9% to 15% of stillbirths are caused by infections. infection may be especially important as a cause of stillbirth occurring early in pregnancy. recognized causes include syphilis, toxoplasmosis, parvovirus b-19, chorioamnionitis, and listeria monocytogenes. other ... | 2002 | 11876570 |
| monoclonal antibodies specific for hippurate hydrolase of campylobacter jejuni. | eleven monoclonal antibodies raised against recombinant campylobacter jejuni hippurate hydrolase were tested for binding to lysates from 19 c. jejuni strains, 12 other campylobacter strains, and 21 non-campylobacter strains. several monoclonal antibodies bound to c. jejuni but not to other campylobacter species and may be useful in a species-specific immunoassay. | 2002 | 11880445 |
| dietary oligofructose and inulin protect mice from enteric and systemic pathogens and tumor inducers. | prebiotics induce changes in the population and metabolic characteristics of the gastrointestinal bacteria, modulate enteric and systemic immune functions, and provide laboratory rodents with resistance to carcinogens that promote colorectal cancer. there is less known about protection from other challenges. therefore, mice of the b6c3f1 strain were fed for 6 wk a control diet with 100 g/kg cellulose or one of two experimental diets with the cellulose replaced entirely by the nondigestible oligo ... | 2002 | 11880573 |
| t memory cells: quality not quantity. | immunological memory to pathogens is associated with clonal expansion and heightened responsiveness of antigen-specific t cells. recent work emphasizes that, for efficient protective immunity, qualitative changes in t memory cells are vitally important. | 2002 | 11882307 |
| combined antimicrobial effect of nisin and a listeriophage against listeria monocytogenes in broth but not in buffer or on raw beef. | the effect of nisin and listeriophage lh7, alone and in combination, on the growth and survival of two strains of listeria monocytogenes in broth and two model food systems, with appropriate controls, was determined. growth curves for both bacterial strains in tryptic soy broth incubated at 7 or 30 degrees c, and with the addition of nisin and/or listeriophage at lag, mid-exponential or early stationary phase, were obtained by measuring absorbance at 550 nm. numbers of mixed populations of both ... | 2002 | 11883676 |