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effects of amiodarone-induced phospholipidosis on pulmonary host defense functions in rats.the effect of the induction of pulmonary phospholipidosis by amiodarone on selected pulmonary host defense functions was studied in male fischer-344 rats. one week of daily amiodarone treatment resulted in a 4.5-fold increase in total phospholipid in alveolar macrophages recovered from the lungs by bronchoalveolar lavage. the presence of the phospholipidosis had no effect on the phagocytosis of heat-killed yeast cells, the induction of luminol-dependent chemiluminescence, or the spontaneous rele ...19968618940
safety evaluation of a polymerized hemoglobin solution in a murine infection model.several investigators have observed that free hemoglobin may increase the mortality rate in experimental escherichia coli peritonitis in animals. this effect is probably mediated by the heme moiety of hemoglobin, but the mechanism remains controversial. free hemoglobin might impair neutrophil function, and it might serve as a source of iron, which is necessary for bacterial replication. several modified hemoglobin solutions, developed as blood substitutes, are currently being tested in clinical ...19968621979
the inlab locus mediates the entry of listeria monocytogenes into hepatocytes in vivo.the intracellular parasite listeria monocytogenes is able to induce its internalization by cultured mammalian cells that are not normally phagocytic. this process requires the expression of the chromosomal locus inlab. we studied the virulence of an inlab mutant and of its parent in murine listeriosis. irrespective of the route of inoculation, the inlab mutant was severely attenuated for growth in the liver. the livers of mice inoculated with the inlab mutant displayed much smaller infectious fo ...19968627149
listeria monocytogenes meningoencephalitis: murine models vs. the naturally occurring disease in ruminants. 19968627350
antiviral cytotoxic t-cell memory by vaccination with recombinant listeria monocytogenes.listeria monocytogenes is a facultative intracellular bacterium that is able to escape phagocytic vesicles and replicate in the cytoplasm of infected cells. as with viral vectors, this intracytoplasmic life cycle provides a means for introducing foreign proteins into the major histocompatibility complex class i pathway of antigen presentation. using recombinant l. monocytogenes (rlm) strains expressing the full-length nucleoprotein (np) or a single cytotoxic t-lymphocyte (ctl) epitope from lymph ...19968627765
effects of ultraviolet-b exposure on the resistance to listeria monocytogenes in the rat.a rat infection model using the bacterial pathogen listeria monocytogenes was employed to analyze the immunosuppressive activity of uvb radiation. rats were exposed to suberythemal doses of uvb radiation for 5 or 7 consecutive days, using kromayer or fs40 lamps respectively. subsequently, the rats were infected subcutaneously or intravenously with listeria. exposure to uvb resulted in an increased number of bacteria in the spleen 4 days after infection. listeria-specific lymphocyte proliferation ...19968628759
delivery of macromolecules into cytosol using liposomes containing hemolysin from listeria monocytogenes.the cytosolic space of cells is an important but relatively inaccessible target for the delivery of therapeutic macromolecules. here we describe the efficient delivery of macromolecules into the cytosolic space of macrophages from liposomes that contain listeriolysin o (llo), the hemolytic protein of listeria monocytogenes that normally mediates bacterial passage from phagosomes into cytosol. llo was purified and encapsulated inside ph-sensitive liposomes, along with other molecules to be delive ...19968631734
adaptive acid tolerance response in listeria monocytogenes: isolation of an acid-tolerant mutant which demonstrates increased virulence.the ability of listeria monocytogenes to tolerate low-ph environments is of particular importance because the pathogen encounters such environments in vivo, both during passage through the stomach and within the macrophage phagosome. in our study, l. monocytogenes was shown to exhibit a significant adaptive acid tolerance response following a 1-h exposure to mild acid (ph 5.5), which is capable of protecting cells from severe acid stress (ph 3.5). susceptibility to ph 3.5 acid is growth phase de ...19968633868
recovery of different listeria ribotypes from naturally contaminated, raw refrigerated meat and poultry products with two primary enrichment media.isolation rates for listeria monocytogenes and the other listeria spp. typically improve when samples are enriched in more than one primary enrichment medium. this study evaluated the abilities of two primary enrichment media, university of vermont-modified listeria enrichment broth (uvm) and listeria repair broth (lrb), to recover different ribotypes of listeria spp. from raw meat and poultry samples. forty-five paired 25-g retail samples of ground beef, pork sausage, ground turkey, and chicken ...19968633878
the effects of inhibitors of vacuolar acidification on the release of listeria monocytogenes from phagosomes of caco-2 cells.to evaluate the role of the acidic ph of phagosomes on the invasive ability and fate of listeria monocytogenes within host cells, entry and replication of this gram-positive bacterium in a human enterocyte-like cell line (caco-2) were investigated by a combination of biochemical and ultrastructural approaches. the effects of inhibitors of vacuolar acidification--the lipophilic weak base ammonium chloride, the carboxylic ionophore monensin and the vacuolar proton atpase inhibitor bafilomycin a1-- ...19968636958
in vitro conjugative transfer of vana vancomycin resistance between enterococci and listeriae of different species.in a study designed to gain data on the in vitro transferability of vancomycin resistance from enterococci of the vana phenotype to listeriae of different species, three clinical enterococcus isolates-enterococcus faecium ls10, enterococcus faecalis ls4, and enterococcus faecalis a3208, all harboring a plasmid that strongly hybridized with a vana probe-were used as donors in transfer experiments. strains of five listeria species were used as recipients. from enterococcus faecium ls10, glycopepti ...19968641304
identification and purification of novel internalin-related proteins in listeria monocytogenes and listeria ivanovii.monoclonal antibodies were generated against a 30-kda protein fraction derived from culture supernatants of a listeria monocytogenes strain complemented with additional copies of the prfa regulator gene. several of the antibodies reacted specifically with a hitherto unidentified, secreted 30-kda polypeptide. by immunoblot analysis, the expression of this 30kda polypeptide was found to be dependent on the presence of the prfa regulator protein. microsequencing of peptides derived from the partial ...19968641748
epidemiologic evaluation of encephalitic listeriosis in goats.to evaluate host and environmental factors associated with the development of encephalitic listeriosis in goats.19968641953
effect of pre- and post-heat shock temperature on the persistence of thermotolerance and heat shock-induced proteins in listeria monocytogenes.the effect of incubation temperature, before and after a heat shock, on thermotolerance of listeria monocytogenes at 58 degrees c was investigated. exposing cells grown at 10 degrees c and 30 degrees c to a heat shock resulted in similar rises in thermotolerance while the increase was significantly higher when cells were grown at 4 degrees c prior to the heat shock. cells held at 4 degrees c and 10 degrees c after heat shock maintained heat shock-induced thermotolerance for longer than cells hel ...19968642016
superior efficacy of secreted over somatic antigen display in recombinant salmonella vaccine induced protection against listeriosis.vaccination provides the most potent measure against infectious disease, and recombinant (r) viable vaccines expressing defined pathogen-derived antigens represent powerful candidates for future vaccination strategies. in a new approach we constructed r-aroa- salmonella typhimurium displaying p60 or listeriolysin (hly) antigen of listeria monocytogenes in secreted or somatic form in the host cell. vaccination of mice with r-aroa- s. typhimurium induced protection against the intracellular pathog ...19968643654
complement receptor type 3 mediates phagocytosis and killing of listeria monocytogenes by a tnf-alpha- and ifn-gamma-stimulated macrophage precursor hybrid.previous work demonstrated that engagement of complement receptor type 3 (cr3) was required for inflammatory peritoneal macrophages to phagocytose and kill the facultative intracellular bacterium listeria monocytogenes. the experiments described here tested the role of cr3 in phagocytosis and killing of listeria by a clonal population of tnf-alpha/ifn-gamma-stimulated macrophage precursor hybrids. stimulation with tnf-alpha and ifn-gamma increased cr3 expression 20-fold and induced a big increas ...19968612281
bacteroides fragilis enterotoxin modulates epithelial permeability and bacterial internalization by ht-29 enterocytes.enterotoxigenic bacteroides fragilis has been associated with diarrheal disease, and the enterotoxin has a cytopathic effect on cultured ht-29 enterocytes. experiments were designed to determine the effect of b. fragilis enterotoxin on bacteria-enterocyte interactions.19968613048
a recombinant minigene vaccine containing a nonameric cytotoxic-t-lymphocyte epitope confers limited protection against listeria monocytogenes infection.we have previously shown that vaccines expressing virus-derived cytotoxic-t-lymphocyte (ctl) epitopes as short minigenes can confer effective protection against virus challenges, and here we extend these studies to the bacterium listeria monocytogenes. host defense against this important human pathogen appears largely t cell mediated, and a nonamer ctl epitope from the listeriolysin o (llo) protein has been identified in balb/c mice. we have synthesized this nonamer as a minigene, expressed it i ...19968613379
control of natural killer cell-mediated innate resistance against the intracellular pathogen listeria monocytogenes by gamma/delta t lymphocytes.listeria monocytogenes is an intracellular bacterium which causes an acute infectious disease in mice. initial host resistance depends on innate immunity mediated primarily by natural killer (nk) cells followed by specific alpha/beta t cells, which are central to acquired specific immunity. gamma/delta t lymphocytes seem to provide a link between the innate and the specific immune response. all these lymphocyte populations produce gamma interferon (ifn-gamma), which, because of its macrophage-ac ...19968613386
peptide epitopes from noncytosolic listeria monocytogenes can be presented by major histocompatibility complex class i molecules.listeria monocytogenes is an intracellular pathogen which escapes the phagosome and resides in the cytosol of the host cell. using listeria innocua and a mutant strain of l. monocytogenes (listeriolysin o negative), which do not enter the cytosol of the host cell, we demonstrate class i presentation of an epitope of p60, a protein secreted by l. monocytogenes, to a class i-restricted cd8+ cytotoxic t lymphocyte clone.19968613407
administration of interleukin-10 abolishes innate resistance to listeria monocytogenes.we have used severe-combined immunodeficient (scid) mice to examine the immunoregulatory effects of interleukin (il)-10 on innate resistance to infection with listeria monocytogenes. addition of heat killed listeria to spleen cells from naive scid mice resulted in secretion of interferon (ifn)-gamma from natural killer cells in vitro. this response was enhanced up to 15-fold in the presence of exogenous il-2, but was completely ablated by addition of il-10 with ic50 of less than 0.5 u/ml. infect ...19968617304
salmonella typhimurium aroa- infection in gene-targeted immunodeficient mice: major role of cd4+ tcr-alpha beta cells and ifn-gamma in bacterial clearance independent of intracellular location.due to the dependency on aromatic precursors, the growth of salmonella typhimurium aroa- is limited in immunocompetent mice. here we show that h-21-a beta-/- mice (lacking mhc class ii molecules and thus devoid of mature cd4+ tcr-alpha beta cells), tcr-beta-/- mice (devoid of tcr-alpha beta cells), and ifn-gamma r-/- mice (unresponsive to ifn-gamma) are highly susceptible to s. typhimurium aroa- infection compared with heterozygous controls. in contrast, beta 2m-deficient mice (lacking surface m ...19968617956
[listeria meningitis in adults]. 19968618625
the adjuvancy of silicones: dependency on compartmentalization.studies have been conducted in mice (b6c3f1) and rats (sprague dawley, fischer 344) to investigate the adjuvancy potential of silicone mammary gel and the low molecular weight silicone fluid, octamethylcyclotetrasiloxane (d4). dependent on the experimental conditions employed, a divergent data profile emerges. if the antigen (bovine serum albumin, bsa) is emulsified with either the gel or the d4 prior to intramuscular immunization, an amplified anti-bsa igg antibody response, as measured by mult ...19968565549
enter listeria, unruffled. 19968596949
automated rna probe assay for the identification of listeria monocytogenes.recent epidemics of human listeriosis have shown the importance of listeria monocytogenes as a food-borne risk. we have developed an automated identification assay for l. monocytogenes using the specificity of the 16s rdna probe described by wang et al. (1991). bacterial cultures were lysed quickly by a chemical step releasing the target nucleic acids. extracts were loaded into the vidas automate (biomérieux) which performed a non-radio-active hybridisation reaction for 2 h. this assay recognise ...19968652341
multilocus enzyme electrophoresis typing of new zealand listeria monocytogenes isolates.eighty-five strains of listeria monocytogenes, comprising 74 strains isolated from the environment, humans, animals and foods in new zealand; 10 strains from similar sources in denmark, and one reference strain, were studied using multilocus enzyme electrophoresis (mee). fifty-five electrophoretic types (ets) were identified among the 85 strains, most (71%) of which were represented by only one isolate. the 74 new zealand isolates produced 45 ets, most (67%) of which were represented by only one ...19968652343
cloning and genetic organization of the bacteriocin 31 determinant encoded on the enterococcus faecalis pheromone-responsive conjugative plasmid pyi17.the conjugative plasmid pyi17 (57.5 kb) isolated from enterococcus faecalis yi717 confers a pheromone response on the host and encodes the bacteriocin 31 gene. bacteriocin 31 is active against e. hirae 9790, e. faecium, and listeria monocytogenes. pyi17 was mapped physically by restriction enzyme analysis and the relational clone method. deletion mutant and sequence analyses of the ecori fragment b cloned from pyl17 revealed that a 1.0-kb fragment contained the bacteriocin gene (baca) and an imm ...19968655558
differential regulation of ia expression and antigen presentation by listeriolysin-producing versus non-producing strains of listeria monocytogenes.listeria monocytogenes is an intracellular bacterial pathogen. a single gene product, listeriolysin (llo), is critical for the induction of protective immunity. we now show that listeria that produce functional llo augment ia expression by macrophages and are better presented to a th1, cd4+ anti-listeria t cell line. we used two genetically engineered strains of listeria which differed only in their ability (ly+) or inability (ly-) to produce functional llo. ia-negative murine macrophages ingest ...19968656053
prevalence of listeria monocytogenes and other listeria spp.in smoked and 'gravad' fish.altogether 150 samples of vacuum-packed fish were examined for the presence of listeria species. listeria monocytogenes were isolated from 12 of 58 'gravad' fish samples, 3 of 26 cold-smoked and one of 66 hot-smoked fish samples. ten of these 16 positive samples harboured more than 100 l. monocytogenes cfu/g. the highest level (132,000) was found in a sample of hot-smoked rainbow trout (oncorhynchus mykiss). serogroup 1/2 was most frequently found, followed by 4 and 3. one sample of gravad rainb ...19968659342
extracellular iron reductase activity produced by listeria monocytogenes.little is known about how pathogenic microorganisms that do not produce low-molecular-weight iron-chelating agents, termed siderophores, acquire iron from their environment. we have identified an extracellular enzyme produced by listeria monocytogenes that can mobilize iron from a variety of iron-chelate complexes via reduction of the metal. the iron reductase requires mg2+, flavin mononucleotide (fmn), and reduced nicotinamide adenine dinucleotide (nadh) for activity. saturation kinetics were f ...19968661944
the nuclear kluyveromyces lactis mrf1 gene encodes a mitochondrial class i peptide chain release factor that is important for cell viability.we report the isolation and characterization of the kluyveromyces lactis mrf1 gene encoding mitochondrial peptide chain release factor mrf-1. over-expression of the klmrf1 gene has a strong antisuppressive effect in a saccharomyces cerevisiae mitochondrial nonsense suppressor strain. inactivation of klmrf1 results in a dual phenotype: most cells die after about 10-13 generations, while a small number of cells exceed this limit. we propose that the lethality is related to a loss of mitochondrial ...19968662205
phagocytosed live listeria monocytogenes influences rab5-regulated in vitro phagosome-endosome fusion.survival or destruction of a pathogen following phagocytosis depends, in part, on fusion events between the phagosome and the endosomal or lysosomal compartments. here we use an in vitro assay to show that phagosome-endosome fusion is regulated by the small gtpase rab5 and that fusion events are influenced by an internalized live organism, listeria monocytogenes (lm). we compare the in vitro fusion of phagosomes containing heat-killed organisms (dead lm) with that of phagosomes containing a live ...19968662791
suppression of t-helper type-1 immune response against listeria monocytogenes by treatment of mice with goat antibodies to mouse igd.injection of goat anti-mouse igd antibodies (gam igd) to mice has been shown to induce polyclonal igg1 and ige production by b cells and interleukin-4 (il-4) production by goat ig-specific t cells. surface igd cross-linking also activates b cells to function as antigen-presenting cells (apc). although the gam igd treatment is a well-established system for analysis of b-cell dependent antigen presentation, the influence of gam igd treatment on the immune response to irrelevant antigens is not kno ...19968666428
evidence for the early recruitment of t-cell receptor gamma delta+ t cells during rat listeriosis.we have previously reported that heat-shock protein (hsp) 60-reactive t-cell receptor (tcr)gamma delta+ t cells appear in the peritoneal cavity during the early stage of infection with listeria monocytogenes in mice. in this study, we examined the kinetics of tcr gamma delta+ t cells during listeriosis in f344 rats by flow cytometry using a v65 monoclonal antibody (mab) directed to a constant determinant of rat tcr gamma delta chains. tcr gamma delta+ t cells significantly increased in the perit ...19968666431
bias in the gamma delta t cell response to listeria monocytogenes. v delta 6.3+ cells are a major component of the gamma delta t cell response to listeria monocytogenes.despite extensive research, the role that gamma delta t cells play in the immune response to infectious disease has yet to be established. here we report the generation of a mab specific for the v delta 6.3 tcr and investigate the gamma delta+ and v delta 6.3+ t cell responses to the intracellular bacterium listeria monocytogenes in balb/c mice. by infecting animals with various doses of listeria and analyzing the components of the cellular immune response at the two primary sites of infection, ...19968666799
[infections caused by listeria monocytogenes]. 19968668235
multiple immune abnormalities in tumor necrosis factor and lymphotoxin-alpha double-deficient mice.to investigate the roles of tumor necrosis factor (tnf) and lymphotoxin (lt)-alpha in the development and function of the immune system, the tnf and ltalpha genes were simultaneously inactivated in mice by homologous recombination. these mutant mice are highly susceptible to listeria monocytogenes infection and resistant to endotoxic shock induced by the combined administration of d-galactosamine (d-gain) and lipopolysaccharide (lps). their splenic microarchitecture is disorganized, characterize ...19968671586
h2-m3wt-restricted, listeria monocytogenes-specific cd8 t cells recognize a novel, hydrophobic, protease-resistant, periodate-sensitive antigen.mice infected with listeria monocytogenes (lm) generate h2-m3wt-restricted cd8 effectors which recognize a heat-killed lm-associated antigen (haa) presented by macrophages. to characterize haa, we extracted a bioactive component from lm using sds or naoh. extracted haa aggregated in hydrophilic solvents but dissociated in the presence of sds into a smaller subunit which migrated in sephadex g-200 between chymotrypsinogen (25 kda) and cytochrome c (12.5 kda). haa bioactivity and size was unaffect ...19968671623
development of a polymerase chain reaction assay for the detection of listeria monocytogenes in foods.species-specific oligonucleotide primers were selected from the coding region of the listeriolysin o gene of listeria monocytogenes and were used in conjunction with genus-specific primers and an internal control fragment for polymerase chain reaction amplification. the specificity of the primers was confirmed by testing 40 isolates of l. monocytogenes, other listeria species and other micro-organisms which are ubiquitous in the environment. the reliability of these primers was further tested in ...19968672273
behaviour of listeria monocytogenes during the traditional manufacture of water-buffalo mozzarella cheese.the behaviour of a four-strains mixture of listeria monocytogenes (strains scott a, v7, oh and cal) during the traditional manufacture of water-buffalo mozzarella cheese was investigated at two levels of inoculation: ca 10(5) and 10(3) cfu ml-1 of vat milk. no significant change in listeria counts was observed during the curd ripening (4.0-4.5 h), at the end of which the ph ranged between 4.83 and 4.91. a decrease of about 2 log was observed after stretching of the curd in hot water (95 degrees ...19968672274
the clones of listeria monocytogenes detected in food depend on the method used.restriction enzyme analysis (rea) with pulsed-field gel electrophoresis (pfge) has been used to characterize and compare listeria monocytogenes strains isolated from foods by two methods, an enrichment procedure and a direct plating procedure. in total 151 isolates from nine foods were investigated. in six of the foods (101 strains investigated) only one clone of l. monocytogenes was found irrespective of the method used. in three foods (50 strains investigated) the direct plating procedure yiel ...19968672279
lipoteichoic acid preparations of gram-positive bacteria induce interleukin-12 through a cd14-dependent pathway.interleukin 12 (il-12) strongly augments gamma interferon production by natural killer (nk) and t cells. il-12 also promotes effective cell-mediated immune responses, which are particularly important against intracellular bacteria such as listeria monocytogenes. while the lipopolysaccharide (lps) of gram-negative bacteria induces monocyte production of il-12, the relevant gram-positive components which induce il-12 production are uncharacterized. we used the human monocytic cell line thp-1 to st ...19968675286
the acta polypeptides of listeria ivanovii and listeria monocytogenes harbor related binding sites for host microfilament proteins.the surface-bound acta polypeptide of the intracellular bacterial pathogen listeria monocytogenes acts as a nucleator protein, generating the actin cytoskeleton around intracellularly motile bacteria. in this work, we examined the functional similarity of acta from listeria ivanovii (iacta) atcc 19119 to its l. monocytogenes counterpart. the amino acid sequence of iacta predicts a molecular mass of 123 kda and harbors eight proline-rich repeats. for functional analysis, various iacta derivatives ...19968675289
neutralizing monoclonal antibodies against listeriolysin: mapping of epitopes involved in pore formation.six different mouse monoclonal antibodies (mabs) and a specific rabbit polygonal antibody were raised against listeriolysin. four of the mabs also recognized seeligeriolysin, and five cross-reacted with ivanolysin. the hemolytic activity could be neutralized by the polygonal antibody as well as by five of the mabs. none of the neutralizing antibodies interfered with the binding of listeriolysin to the cellular membrane. the epitopes recognized by the mabs were localized by using overlapping synt ...19968675351
listeriolysin o activates mitogen-activated protein kinase in eucaryotic cells.infection with listeria monocytogenes induces the activation of mitogen-activated protein (map) kinase in several tissue culture cell lines (p.tang, i. rosenshine, and b. b. finlay, mol. biol. cell 5:455-464, 1994). after various mutants were examined, the bacterial factor responsible for map kinase activation was identified as listeriolysin o (llo). growth supernatant containing llo or purified llo alone can induce map kinase tyrosine phosphorylation in hela cells. single-amino-acid mutations i ...19968675352
inhibitory effects of sucrose monolaurate, alone and in combination with organic acids, on listeria monocytogenes and staphylococcus aureus.the effects of sucrose esters of fatty acids, alone and in combination with ethylenediaminetetraacetic acid (edta), acetic acid, lactic acid and citric acid, on survival, growth and thermal inactivation of listeria monocytogenes and staphylococcus aureus were determined. the presence of sucrose monocaprate (400 micrograms ml-1) in tryptose phosphate broth (tpb) or tryptic soy broth (tsb) did not inhibit the growth of l. monocytogenes or staph. aureus, respectively. however, significantly (p < or ...19968675484
relationship between variations in pathogenicity and lag phase at 37 degrees c of listeria monocytogenes previously stored at 4 degrees c.three haemolytic, pathogenic strains of listeria monocytogenes (a reference strain, a food-derived strain and a human strain) were held at 4 degrees c for 4 weeks in phosphate-buffered saline ph 5.5 or 7.0, with and without 0.2% potassium sorbate or 0.3% sodium acetate. the number of viable cells did not change significantly during this storage. pathogenicity of non-growing l. monocytogenes cells for 14-d-old chick embryos was determined before and after storage. storage at 4 degrees c resulted ...19968679139
repetitive element sequence-based pcr for species and strain discrimination in the genus listeria.repetitive element sequence-based pcr (rep-pcr) was used to generate dna fingerprints for listeria spp. two primer sets (rep 1r-i rep 2-i and eric 1r eric 2) used in respectively rep- and eric-pcr revealed that bacteria of the genus listeria possess short repetitive extragenic palindromic elements and enterobacterial repetitive intergenic consensus sequences. specific band profiles obtained by eric-pcr enabled the identification of listeria species. with both rep- and eric-pcr the l. monocytogen ...19968679144
effect of hypoxia on enterocyte endocytosis of enteric bacteria.to clarify the effect of hypoxia on bacteria-enterocyte interactions.19968681603
the role of p56lck in the development of gamma delta t cells and their function during an infection by listeria monocytogenes.we investigated roles of p56lck tyrosine kinase (lck) on the development and function of gamma delta t cells in adult mice using lck gene knockout (lck -/-) mice. the mature gamma delta t cells (heat-stable ag negative) were generated significantly in the thymi of adult lck -/- mice. when listeria monocytogenes was infected i.p., gamma delta t cells were induced in the peritoneal cavity of the lck -/- mice. interestingly, the repertoire of gamma delta t cells was obviously different in the lck + ...19968683122
response of a gamma delta+ t cell receptor invariant subset during bacterial infection.murine gamma delta t cells can be divided into subsets based on the tcr gamma-chains they express. most of these subsets have variable tcr junctions, but two, both associated with epithelia, express invariant tcrs. the absence of receptor variability in these cells implies uniformity of their ligands. this was previously taken as evidence to suggest that gamma delta t cells recognize host-derived, stress-induced ligands. we now demonstrate, for the first time, the response of a gamma delta tcr i ...19968690911
[pustular dermatitis in veterinarians following delivery in domestic animals; an occupational disease].to assess the prevalence of contact dermatitis after deliveries in cattle or sheep among veterinarians.19968692355
salivacin 140, a novel bacteriocin from lactobacillus salivarius subsp. salicinius t140 active against pathogenic bacteria.fifteen of 353 environmental isolates of lactic acid bacteria consistently showed activity against listeria monocytogenes, streptococcus mutans, actinomyces viscosus, and/or propionibacterium acnes. strain t140, isolated from the surface of japanese pampas grass leaves and identified as lactobacillus salivarius subsp. salicinius, also had activity against several lactobacillus species, staphylococcus aureus and yersinia enterocolitica. since the antagonistic factor(s) produced by t140 was sensit ...19968695066
thermal inactivation of listeria monocytogenes during rapid and slow heating in sous vide cooked beef.heating at slowly rising temperatures is suspected to enhance thermotolerance in listeria monocytogenes and, since anaerobic environments have been shown to facilitate resuscitation of heat-injured cells of this micro-organism, concern may arise about the possibility of l. monocytogenes surviving in minimally preserved products. the effect of rapid ( > 10 degrees c min-1) and slow (0.3 and 0.6 degrees c min-1) heating on survival of l. monocytogenes in sous vide cooked beef was therefore examine ...19968695067
the effect of nisin on listeria monocytogenes in culture medium and long-life cottage cheese.the sensitivity to nisin of 27 strains of listeria monocytogenes, four of l. innocua and one of l. ivanovii was estimated at ph 6.8 and ph 5.5. strains of l. monocytogenes showed differences in sensitivity which were not correlated with serotype. strains of l. innocua were as resistant as the most resistant strains of l. monocytogenes, whereas the strain of l. ivanovii was relatively sensitive. two of the most resistant strains of l. monocytogenes multiplied in aerated liquid medium adjusted to ...19968695069
confirmation and identification of listeria spp.all confirmation and identification methods used in this study can be used for the screening of suspected colonies on isolation media for listeria spp. in traditional enrichment procedures the microscreen listeria latex test gives fast results. the dna probes (accuprobe and gene-trak) are very specific in detecting listeria monocytogenes. for identification of listeria spp. both tests (api and micro-id) performed equally well. preference may be given to the api test, since differentiation of l. ...19968695071
human gamma/delta t-cell response to listeria monocytogenes protein components in vitro.listeria monocytogenes is a facultative intracellular pathogen that replicates inside mononuclear phagocytes and induces specific cellular immunity. listeriosis encompasses many clinical syndromes and meningitis is the most frequent clinical manifestation. human alpha/beta and gamma/delta t cells have been shown to respond to l. monocytogenes antigens and to play an important role in resistance against listerial infection. we investigated the nature of listerial ligands and the influence of the ...19968698384
cytotoxic-t-lymphocyte responses to epitopes of listeriolysin o and p60 following infection with listeria monocytogenes.in order to test the influence of the cell surface density of a specific h2-kd-presented epitope on the subsequent level of the cytotoxic-t-lymphocyte (ctl) response directed against the epitope, we investigated the ctl response to two secreted products of listeria monocytogenes from mice immunized with viable l. monocytogenes. we determined the response to the h2-kd-presented amino acid 91 to 99 (aa91-99) immunodominant peptide of listeriolysin o (llo) and to the aa217-225 immunodominant peptid ...19968698474
monocytes of individual human subjects display heterogeneous bacterial uptake and antilisterial activity.peripheral blood monocytes (mo) of normal human donors simultaneously exhibit two subsets differing in their functional activity towards the facultative intracellular bacterium listeria monocytogenes. one subset (on average, 25% of total mo) was characteristically able to ingest a large number of l. monocytogenes bacteria and permitted intracellular growth of these bacteria. the other mo subpopulation (on average, 75% of total mo) was far less active in phagocytosing l. monocytogenes and restric ...19968698493
effect of granulocyte colony-stimulating factor on the course of infection with gram-positive bacteria in mice during granulocytopenia induced by sublethal irradiation or cyclophosphamide.this study assesses the effect of granulocyte colony-stimulating factor (g-csf) on the outcome of infection with listeria monocytogenes or staphylococcus aureus in mice during leukocytopenia induced by sublethal total body irradiation or cyclophosphamide treatment. the role of granulocytes during infection was assessed in the thigh muscle, spleen, and liver. g-csf treatment in naive mice increased the number of blood granulocytes; upon infection, these numbers increased further, but g-csf did no ...19968699079
impaired il-12 responses and enhanced development of th2 cells in stat4-deficient mice.interactions between cytokine and receptor lead to the activation of multiple signalling molecules, including the family of signal transducer and activator of transcription (stat) proteins. stat4 is one member of this family, and is activated only in response to the cytokine interleukin (il)-12 (refs 5, 6). by gene targeting, we have generated mice deficient in stat4 to determine whether the function of this transcription factor is redundant with other signalling molecules activated by il-12. il ...19968700209
[infections caused by listeria monocytogenes]. 19968700286
characterization of the chemical and antimicrobial properties of piscicolin 126, a bacteriocin produced by carnobacterium piscicola jg126.a novel peptide bacteriocin produced by the lactic acid bacterium carnobacterium piscicola jg126 isolated from spoiled ham was purified and characterized. this bacteriocin, designated piscicolin 126, inhibited the growth of several gram-positive bacteria, especially the food-borne pathogen listeria monocytogenes, but had no effect on the growth of a number of yeasts and gram-negative bacteria. bactericidal activity was not destroyed by exposure to elevated temperatures at low ph values; however, ...19968702282
modified listeria bacteriophage lysin genes (ply) allow efficient overexpression and one-step purification of biochemically active fusion proteins.listeria bacteriophage lytic enzymes are useful for in vitro applications such as rapid, gentle cell disruption, and they provide new approaches as selective antimicrobial agents for destruction of listeria monocytogenes in contaminated foods. we describe here the amino-terminal modification of three cloned listeria phage lysin genes (ply), resulting in fusion proteins with a 12-amino-acid leader containing six consecutive histidine residues. the recombinant enzymes retain their native specific ...19968702301
the requirement of tumour necrosis factor-alpha and interferon-gamma for the expression of protective immunity to secondary murine tularaemia depends on the size of the challenge inoculum.the present study was conducted to determine the extent to which the cytokines tumour necrosis factor-alpha (tnf-alpha) and interferon-gamma (ifn-gamma) are required to protect against primary or secondary murine tularaemia caused by the live vaccine strain of the facultative intracellular bacterium francisella tularensis. it is shown that non-immune mice treated with neutralizing monoclonal antibodies (mabs) against tnf-alpha and ifn-gamma are rendered defenceless against otherwise sublethal in ...19968704976
analysis of the sakacin p gene cluster from lactobacillus sake lb674 and its expression in sakacin-negative lb. sake strains.sakacin p is a small, heat-stable, ribosomally synthesized peptide produced by certain strains of lactobacillus sake. it inhibits the growth of several gram-positive bacteria, including listeria monocytogenes. a 7.6 kb chromosomal dna fragment from lb. sake lb674 encompassing all genes responsible for sakacin p production and immunity was sequenced and introduced into lb. sake strains lb790 and lb706x which are bacteriocin-negative and sensitive to sakacin p. the transformants produced sakacin p ...19968704983
rp 59500, a streptogramin derivative, is effective in murine listeriosis.rp 59500 (synercid) a streptogramin derivative, is a mixture of two water-soluble substances, rp 57669 (quinupristin), and rp 54476 (dalfopristin). it was tested in vitro and in vivo against listeria strains. all strains were sensitive in vitro. the mics of 60 strains of listeria monocytogenes, l. seeligeri, l. ivanovii, and l. innocua were between 0.156 and 0.625 mg/l. strains of l. grayi were inhibited by 1.25 mg/l of rp 59500. in contrast to its bactericidal effect against other gram-positive ...19968708741
interaction of environmental chemicals with respiratory sensitization.the acute effects of the inhalation of air polluting agents have been examined by many research groups in both animal models and human beings. for instance, it is evident that exposure to ozone has toxic effects and can lead to lung function disturbances. for this reason it is likely that individuals suffering from copd or asthma are groups especially at risk with respect to the effects of ozone. the majority of studies dealing with effects of air pollutants on pulmonary allergy are restricted t ...19968711768
molecular mechanisms of lymphocyte-mediated cytotoxicity and their role in immunological protection and pathogenesis in vivo.studies with perforin-deficient mice have demonstrated that two independent mechanisms account for t cell-mediated cytotoxicity: a main pathway is mediated by the secretion of the pore-forming protein perforin by the cytotoxic t cell, whereas an alternative nonsecretory pathway relies on the interaction of the fas ligand that is upregulated during t cell activation with the apoptosis-inducing fas molecule on the target cell. nk cells use the former pathway exclusively. the protective role of the ...19968717513
isolation of yersinia pseudotuberculosis and listeria monocytogenes serotype 4 from a gray fox (urocyon cinereoargenteus) with canine distemper.in february 1993, clinical, pathological, and microbiological investigations were performed on an adult female gray fox (urocyon cinereoargenteus) from northern mississippi (usa). the fox had clinical signs consistent with canine distemper virus encephalitis. eosinophilic inclusions characteristic of canine distemper virus were in the nuclei and cytoplasm of cerebral neurons and glial cells and in the cytoplasm of urinary, gastric, pancreatic and biliary epithelial cells. the liver contained mul ...19968722280
effect of recombinant human gamma interferon on intracellular activities of antibiotics against listeria monocytogenes in the human macrophage cell line thp-1.listeria monocytogenes is a facultative intracellular pathogen which enters cells by endocytosis and reaches phagolysosomes from where it escapes and multiplies in the cytosol of untreated cells. exposure of macrophages to gamma interferon (ifn-gamma) restricts l. monocytogenes to phagosomes and prevents its intracellular multiplication. we have tested whether ifn-gamma also modulates the susceptibility of l. monocytogenes to antibiotics. we selected drugs from three different classes displaying ...19968723471
protection of balb/c mice against homologous and heterologous species of brucella by rough strain vaccines derived from brucella melitensis and brucella suis biovar 4.to evaluate stable rough mutants derived from brucella melitensis 16m and b suis 2579 (biovar 4) as vaccines against homologous and heterologous brucella spp in the balb/c mouse model. design, animals, and procedure: rough mutants vtrm1 and vtrs1 were obtained from b melitensis 16m and b suis 2579, respectively, by allelic exchange of rfbu gene encoding mannosyltransferase with a tn5-disrupted rfbu gene. mice were vaccinated with vtrm1 or vtrs1 and challenge exposed 8 weeks later.19968723881
antibacterial activity of quinupristin/dalfopristin. rationale for clinical use.most gram-positive organisms are highly susceptible to the streptogramin, quinupristin/dalfopristin (rp 59500; synercid). minimum inhibitory concentrations for 90% of isolates (mic90) were < or = 1 mg/l for staphylococcus aureus, s. epidermidis, s. haemolyticus, streptococcus pneumoniae, s. pyogenes and listeria monocytogenes. importantly, quinupristin/dalfopristin shows similar activity against methicillin-susceptible and -resistant strains of s. aureus, and streptococci with benzylpenicillin ( ...19968724814
deficient tumor necrosis factor secretion by cord blood mononuclear cells upon in vitro stimulation with listeria monocytogenes.we examined the production of tumor necrosis factor (tnf) by mononuclear cells (mnc) after incubating adult or cord blood mnc with listeria monocytogenes in vitro. with adult mnc cultures, we found that tnf activity reached a peak at 6 h (606 +/- 120 x 10(3) units/liter) and declined to the baseline by day 3. in contrast, using cord blood mnc, we found that tnf activity increased gradually reaching a peak at 24 h. in addition, the peak tnf activity using newborn mnc (189 +/- 26 x 10(3) u/liter) ...19968727078
the effect of lead on the bone marrow stem cells of mice infected with listeria monocytogenes.we investigated the effects of lead exposure on the growth and differentiation of bone marrow hematopoietic cells, the so called colony-forming cells, in normal and listeria monocytogenes infected mice (resistant and susceptible strains). we also studied the effects of lead on the serum colony-stimulating activity (csa), as well as on the survival of the mice after the infection. the doses of lead acetate were 13, 130 and 1300 ppm for 10, 30 and 70 d. at the end of this dosing, mice were infecte ...19968727217
ribotype diversity of listeria monocytogenes strains associated with outbreaks of listeriosis in ruminants.ribotyping is a molecular method for the characterization, identification, and typing of bacterial isolates that has value in epidemiological studies. to demonstrate the utility of this technique for typing of listeria monocytogenes, four outbreaks of epizootic listeriosis in ruminants were investigated through coordinated detection and characterization methods utilizing classical microbiology and nucleic acid-based techniques. l. monocytogenes strains isolated from clinical samples and the sila ...19968727881
a study of the influence of biphase calcium phosphate ceramics on bacterial strains: in vitro approach.an in vitro study of the influence of biphase calcium phosphate ceramics (bcpcs) on bacterial strains is presented. the test procedures were carried out in saline test solution to which different quantities (2,4,50,100, and 200 mg) of bcpcs(samples a and b) were added. the influence of bcpcs on standard bacterial strains has been determined by measuring bacterial contamination using the plate count method. the testing method was validated with membrane filtration and direct inoculation in cultur ...19968731210
studies on the cell tropism of listeria monocytogenes in ovine fetal brain cell cultures.the uptake of listeria monocytogenes by cells in primary dissociated brain cell cultures prepared from ovine fetuses at approximately 50 to 60 days of gestation was studied using a sequential double immunofluorescence technique with antibodies against cell type-specific markers and the bacterial pathogen. cell cultures were inoculated with bacteria at day 4, 8, and 15 in vitro. listeria monocytogenes was predominately internalized by cd68-positive macrophages, followed by astrocytes, fibronectin ...19968734635
serodiagnosis of listeriosis based upon detection of antibodies against recombinant truncated forms of listeriolysin o.amino-terminal fragments of listeriolysin o (llo) of 240 and 411 residues (fragments llo240 and llo411, respectively) were expressed in escherichia coli as fusion polypeptides with maltose-binding protein (mbp) with the aim of producing specific antigens for use in serological tests. in western blots (immunoblots) with crude bacterial extracts of the fusion polypeptides, the reactivities of mbp-llo240 and mbp-llo411 with anti-llo antibody (allo)- and anti-streptolysin o antibody (aslo)-positive ...19968735086
comparison of the infectivity of isolates of listeria monocytogenes following intragastric and intravenous inoculation in mice.the infectivity of 19 haemolytic isolates of listeria monocytogenes from different sources (clinical and environmental) and representative isolates from listeria ivanovii and listeria innocua was compared following intragastric (i.g.) and intravenous (i.v.) inoculation in immunocompetent male balb/c mice. there was marked variation in the infectivity of the different isolates by either route but when isolates were ranked in descending order by spleen count, following i.g. administration, the str ...19968737494
[two cases of listeria monocytogenes infection in osaka municipal hospital].we report two cases of sepsis and meningoencephalitis with listeriosis. they died in despite of administering sensitive antibiotics. a 2 day old girl was admitted to our hospital because of fever and cyanosis. listeria monocytogenes type 4b was cultured from blood, csf, throat, urine, ear. she was treated with twice exchange transfusion and sensitive antibiotics (abpc, tob), but died from dic. a 48 year old man suddenly experienced an unconscious condition. a csf culture grew l. monocytogenes ty ...19968741712
molecular and genetic determinants involved in invasion of mammalian cells by listeria monocytogenes. 19968742246
differential inhibition of il-1 alpha and tnf-alpha generation by ammonium metavanadate in murine macrophages.the relationship between immunotoxicity of ammonium metavanadate (nh4vo3) and levels of tumor necrosis factor-alpha (tnf-alpha) and interleukin-1 (il-1) was studied with a nh4vo3-treated murine macrophage-like cell line, 1774 and resident peritoneal macrophages (pem) obtained from treated mice. lipopolysaccharide (lps)-induced elevation of extracellular tnf-alpha in pem and 1774 cells was not markedly affected by prior treatment with vanadate. however, pem from treated mice at 10 mg v/kg (10v) h ...19968751832
differential regulation of cytokine and cytokine receptor mrna expression upon infection of bone marrow-derived macrophages with listeria monocytogenes.cytokine and cytokine receptor mrna expression was analyzed by pcr-assisted amplification of rna extracted from bone marrow-derived macrophages (bmm phi) at different time points after infection with listeria monocytogenes. the mrnas for the cytokines interleukin-1 alpha (il-1 alpha), il-1 beta, and tumor necrosis factor alpha (tnf-alpha) were induced early after infection, whereas il-6 mrna appeared later and even nonhemolytic listeria strains, which are unable to grow inside eukaryotic cells, ...19968751887
cd8 t-cell recognition of macrophages and hepatocytes results in immunity to listeria monocytogenes.cd8 t cells are effective mediators of specific immunity to infection by listeria monocytogenes, a bacterial pathogen that initially infects macrophages in the spleen and liver and subsequently spreads to hepatocytes and unidentified parenchymal cells in the spleen. to identify the in vivo target cells of l. monocytogenes-immune cd8 t cells, adoptive transfer assays were performed with bone marrow chimeric or transgenic host mice which had been manipulated to alter the major histocompatibility c ...19968751910
novel pathogenic mechanism of microbial metalloproteinases: liberation of membrane-anchored molecules in biologically active form exemplified by studies with the human interleukin-6 receptor.certain membrane-anchored proteins, including several cytokines and cytokine receptors, can be released into cell supernatants through the action of endogenous membrane-bound metalloproteinases. the shed molecules are then able to fulfill various biological functions; for example, soluble interleukin-6 receptor (sil-6r) can bind to bystander cells, rendering these cells sensitive to the action of il-6. using il-6r as a model substrate, we report that the metalloproteinase from serratia marcescen ...19968751912
elimination of the listeriolysin o-directed immune response by conservative alteration of the immunodominant listeriolysin o amino acid 91 to 99 epitope.a major h2-kd-presented epitope for antilisterial cytotoxic t lymphocytes (ctls) is the nanomer peptide which corresponds to the amino acid 91 to 99 (aa91-99) sequence from listeriolysin o (llo). although the llo sequence contains at least five additional nanomer peptides which also satisfy the h2-kd binding motif, aa91-99 is the only llo-derived target peptide that is recognized by antilisterial ctls following infection of balb/c mice with listeria monocytogenes. in order to investigate further ...19968751922
transforming growth factor beta is protective in host resistance against listeria monocytogenes infection in mice.the role of transforming growth factor beta (tgf-beta) in host resistance against listeria monocytogenes infection was studied with mice. the constitutive expression of tgf-beta 1 mrna was observed in the spleens and livers of mice before and after infection. injecting the mice with anti-tgf-beta 1 peptide serum resulted in diminished antilisterial resistance, whereas the administration of human platelet-derived tgf-beta 1 enhanced the resistance. moreover, mice were protected against lethal inf ...19968751946
iron availability affects entry of listeria monocytogenes into the enterocytelike cell line caco-2.the influence of iron on the entry of listeria monocytogenes into caco-2 cells was studied. iron availability was found to modify the surface hydrophobicity and protein profile of l. monocytogenes, with the result that cell invasion strongly increased upon bacterial growth in iron-rich medium. the enhanced invasive capability of iron-overloaded l. monocytogenes cells correlates to the higher-level expression of the inlab virulence genes, which were positively iron regulated at the transcriptiona ...19968751952
treatment with the antigranulocyte monoclonal antibody rb6-8c5 impairs resistance of mice to gastrointestinal infection with listeria monocytogenes.treatment with the antigranulocyte monoclonal antibody (mab) rb6-8c5 increased the severity of infection in mice intragastrically inoculated with listeria monocytogenes. most mab rb6-8c5-treated mice died when inoculated intragastrically with as few as 4 x 10(4) l. monocytogenes bacteria, whereas most control mice survived intragastric inoculation with 4 x 10(8) l. monocytogenes bacteria. the increased severity of infection in mab rb6-8c5-treated mice appeared to result from listerial multiplica ...19968751957
mice lacking the tnf receptor p55 fail to resolve lesions caused by infection with leishmania major, but control parasite replication.tnf is involved in host resistance to several pathogens. recently it was found that mice lacking the p55 receptor for tnf (tnfrp55 -/-) do not control growth of the intracellular bacteria, listeria monocytogenes and mycobacterium tuberculosis. here we report that the course of infection in tnfrp55 -/- mice with another intracellular pathogen, the protozoan parasite leishmania major, is also quite different from normal mice. tnfrp55 -/- mice developed larger lesions than control mice and failed t ...19968752935
unimpaired macrophage differentiation and activation in mice lacking the zinc finger transplantation factor ngfi-a (egr1).the zinc finger protein ngfi-a (also called egr1, krox24, or zif268) is a candidate regulator of myeloid cell differentiation. evidence supporting this hypothesis is twofold. first, ngfi-a antisense oligonucleotides prevent macrophage differentiation in hl-60 and u937 myeloid leukemia cell lines and in normal bone marrow cells. second, enforced expression of ngfi-a blocks granulocytic differentiation and promotes macrophage differentiation in hl-60 cells and in the hematopoietic progenitor cell ...19968754857
the presentation of class i and class ii epitopes of listeriolysin o is regulated by intracellular localization and by intercellular spread of listeria monocytogenes.the hemolysin, listeriolysin 0 (llo), produced by listeria monocytogenes is both a virulence factor and an immunodominant ag. in this study, we investigated how the lytic activity of llo effects the context of presentation of two known llo epitopes by either class i or class ii mhc molecules. t cell hybridomas were used to monitor each peptide/mhc ligand. apcs infected with strains of listeria expressing hemolytic llo strongly presented the class i mhc epitope; however, this ligand was not well ...19968757622
induction of cytokine gene expression by listeriolysin o and roles of macrophages and nk cells.to determine the role of listeriolysin o (llo) of listeria monocytogenes in the host response at the initial stage of infection, cytokine gene expression in mouse peritoneal exudate macrophages and spleen cells was examined by reverse transcription-pcr. expression of various cytokine mrnas, especially those of interleukin-1 (il-1), tumor necrosis factor alpha, gamma interferon (ifn-gamma), and il-12, was observed to occur in spleen cells after direct stimulation with an llo preparation purified ...19968757852
increased susceptibility to primary infection with listeria monocytogenes in germfree mice may be due to lack of accumulation of l-selectin+ cd44+ t cells in sites of inflammation.the host defense of germfree (gf) mice against primary infection with listeria monocytogenes was compared with that of specific-pathogen-free (spf) mice. in spf mice, the numbers of bacteria in the peritoneal cavity, liver, and spleen decreased gradually to undetectable levels by day 8 after intraperitoneal infection with a sublethal dose (2 x 10(3) cfu) of l. monocytogenes. on the other hand, the elimination of bacteria in these organs of gf mice was significantly impaired at this stage after i ...19968757865
influence of lipoteichoic acid structure on recognition by the macrophage scavenger receptor.lipoteichoic acids (ltas) belong to the immunostimulatory class of molecules of gram-positive bacteria (gpb). previous investigations showed that the macrophage scavenger receptor (sr), a glycosylated trimeric transmembrane protein, binds directly to many gpb, possibly via lta. sr binding to other ligands is dependent upon the spatial characteristics of the repeating negative charge of the ligand. we therefore investigated sr recognition of lta species with various charge densities and distribut ...19968757870
identification of an h2-m3-restricted listeria epitope: implications for antigen presentation by m3.using expression cloning, we have identified an h2-m3-restricted epitope of the intracellular bacterial pathogen listeria monocytogenes. picomolar concentrations of an amino-terminal n-formylated hexapeptide, fmigwii, targeted cells for lysis by cd8+ cytotoxic t cells, while the nonformylated peptide was approximately 100-fold less active. the sequence of the 185 aa protein source of this epitope predicts a transmembrane protein that retains its n terminus and assumes an n(out)-c(in) topology. t ...19968758895
a listeria monocytogenes pentapeptide is presented to cytolytic t lymphocytes by the h2-m3 mhc class ib molecule.polymorphism of mhc class ia molecules severely constrains vaccine development against intracellular pathogens. antigen presentation by mhc class ib molecules, which are generally conserved between different individuals, may circumvent this obstacle. herein, we use tandem mass spectrometry to identify a listeria monocytogenes pentapeptide antigen that is presented to t lymphocytes by the h2-m3 mhc class ib molecule. the peptide contains n-formyl methionine at the n terminus and exclusively hydro ...19968758896
application of antimicrobial-producing lactic acid bacteria to control pathogens in ready-to-use vegetables.five psychrotrophic strains of lactic acid bacteria (lactobacillus casei, lact. plantarum and pediococcus spp.) were isolated from 22 samples of commercial salads. these strains were shown to inhibit aeromonas hydrophila, listeria monocytogenes, salmonella typhimurium and staphylococcus aureus on mrs agar, in salads and in juice prepared from vegetable salads. lactobacillus casei impclc34 was most effective in reducing total mesophilic bacteria and the coliform group; aer. hydrophila, salm. typh ...19968760320
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