Publications

the use of immuno-magnetic separation (ims) as a tool in a sample preparation method for direct detection of l. monocytogenes in cheese.	a sample preparation procedure was developed for direct detection of l. monocytogenes in cheese. the sample preparation protocol consisted of a 10-fold dilution and homogenization, a centrifugation step to precipitate large food particles, passage of the supernatant over a sieve and through a separatory funnel to further eliminate food particles and fat, a centrifugation step to recover the bacterial pellet and finally enzymatic digestion of the suspension to degrade the remaining small food par ...	2000	10777071
specific binding of recombinant listeria monocytogenes p60 protein to caco-2 cells.	the listeria monocytogenes p60 is a major extracellular protein, which is believed to be involved in the invasion of these bacteria into their host cells. so far the mechanism by which p60 participates in the internalization or penetration of l. monocytogenes is still veiled. to determine the possibility of a direct interaction of p60 with the host cell surface, the iap gene was recombinantly expressed in escherichia coli and used for binding studies with the enterocyte-like caco-2 cells. fluore ...	2000	10779709
smoking decreases alveolar macrophage function during anesthesia and surgery.	smoking changes numerous alveolar macrophage functions and is one of the most important risk factors for postoperative pulmonary complications. the current study tested the hypothesis that smoking impairs antimicrobial and proinflammatory responses in alveolar macrophages during anesthesia and surgery.	2000	10781271
an outbreak of febrile gastroenteritis associated with corn contaminated by listeria monocytogenes.	on may 21, 1997, numerous cases of febrile gastrointestinal illness were reported among the students and staff of two primary schools in northern italy, all of whom had eaten at cafeterias served by the same caterer.	2000	10781619
listeria meningitis in children: report of two cases.	we report two cases of meningitis caused by listeria monocytogenes in children. the first patient was a healthy 14-month-old boy and the second patient a 3-year-old girl with byler disease which, however, is not reported as a predisposing factor for listeriosis. we present these cases because listeria infection, although common in neonates, is extremely infrequent during infancy and childhood.	2000	10782402
[investigation of listeria monocytogenes in soft cheeses].	listeria monocytogenes has been recognized as a bacteria that produces severe illness in animals and humans. considering the importance of the presence of l. monocytogenes in soft paste cheeses, a study of diverse cheeses from supermarkets of direct sale to the public was carried out. from the 35 analyzed cheeses, 4 strains were isolated (11.4%). the result of the serological study showed that all the strains corresponded to the serotype 4. the proteic profiles of the isolated strains showed sim ...	2000	10785944
immobilization with metal hydroxides as a means to concentrate food-borne bacteria for detection by cultural and molecular methods.	the application of nucleic acid amplification methods to the detection of food-borne pathogens could be facilitated by concentrating the organisms from the food matrix before detection. this study evaluated the utility of metal hydroxide immobilization for the concentration of bacterial cells from dairy foods prior to detection by cultural and molecular methods. using reconstituted nonfat dry milk (nfdm) as a model, two food-borne pathogens (listeria monocytogenes and salmonella enterica serovar ...	2000	10788338
acid responses of listeria monocytogenes.	the acid response and the correlated protein synthesis in listeria monocytogenes were studied. the lowest ph value which l. monocytogenes could resist was dependent on the strain and the kind of acid used. previous adaptation to an intermediary ph augmented bacterial resistance to a subsequent lethal acidic ph. the acid tolerance was also growth phase dependent. organic volatile acids exerted a more deleterious effect on l. monocytogenes than inorganic acids, because weak acids infer a lower int ...	2000	10791729
mechanism of action of pulsed high electric field (phef) on the membranes of food-poisoning bacteria is an 'all-or-nothing' effect.	salmonella typhimurium (cra 1005) was more sensitive than listeria monocytogenes (nctc 11994) to pulsed high electric field (phef) treatment in distilled water (10, 15 and 20 kv/cm), 10 mm tris-maleate buffer ph 7.4 (15 kv/cm) and model beef broth (0.75% w/v: 15 kv/cm). sublethal injury could not be detected using a selective medium plating technique, indicating that bacterial inactivation by phef may be an 'all-or-nothing' event. phef-induced membrane permeabilization resulted in increased uv-l ...	2000	10791731
proteins variations in listeria monocytogenes exposed to high salinities.	listeria monocytogenes scott a grown in the minimal chemically defined medium m6lt was challenged to a concentration of either 35 or 65 g l(-1) of nacl for 1 h in the presence of a [35s]cysteine-[35s]methionine labelling mix. the protein patterns were analysed by 2d-electrophoresis in the two conditions and isoosmotic condition (5 g l(-1) of nacl in m6lt). a great number of proteins which were synthesized under isoosmotic conditions were either completely repressed or expressed at a reduced leve ...	2000	10791735
modelling the growth of listeria monocytogenes in dynamic conditions.	a recurrent neural network for the prediction of listeria monocytogenes growth under ph and a(w) variable conditions was developed. the use of this model offered the possibility to take into account the consequences of the variations of the factors on l. monocytogenes growth. the effects of solutions, such as nacl, acetic acid and naoh, and their interactions on the response of l. monocytogenes cells were studied. furthermore, the results showed the capacity of the recurrent neural network to pr ...	2000	10791744
production of a nisin-like bacteriocin by lactococcus lactis subsp. lactis a164 isolated from kimchi.	lactococcus lactis subsp. lactis a164 was isolated from kimchi (korean traditional fermented vegetables). the bacteriocin produced by strain a164 was active against closely related lactic acid bacteria and some food-borne pathogens including staphylococcus aureus, listeria monocytogenes and salmonella typhimurium. the antimicrobial spectrum was nearly identical to that of nisin. bacteriocin activity was not destroyed by exposure to elevated temperatures at low ph values, but the activity was los ...	2000	10792514
limitation of adhesion and growth of listeria monocytogenes on stainless steel surfaces by staphylococcus sciuri biofilms.	the adhesion and subsequent development of listeria monocytogenes on stainless steel was studied in the absence and in the presence of a staphylococcus sciuri biofilm. in the three growth media studied, the percentage of adherent cells was reduced to nearly the same extent by the presence of 1-day biofilms of staph. sciuri for the two strains of l. monocytogenes studied. one-day biofilms of staph. sciuri exhibited the same exopolysaccharide content per square centimetre, although they colonized ...	2000	10792517
thermal inactivation of listeria monocytogenes and yersinia enterocolitica in minced beef under laboratory conditions and in sous-vide prepared minced and solid beef cooked in a commercial retort.	d-values were obtained for listeria monocytogenes and yersinia enterocolitica at 50, 55 and 60 degrees c in vacuum-packed minced beef samples heated in a laboratory water-bath. the experiment was repeated using vacutainers, which allowed heating of the beef to the desired temperature before inoculation. d-values of between 0.15 and 36.1 min were obtained for l. monocytogenes. pre-heating the beef samples significantly affected (p < 0.05) the d60 value only. d-values for y. enterocolitica ranged ...	2000	10792520
improved detection of listeria monocytogenes in soft mould-ripened cheese.	in comparison with standard methods, enrichment in half-fraser broth for 24 h at 30 degrees c, followed by plating out onto listeria monocytogenes blood agar (lmba) and palcam medium combined with an additional streak proved to be the most rapid and specific method for the detection of indigenous l. monocytogenes populations from soft mould-ripened cheese. this procedure, with a high sensitivity (93%) and a low detection limit (1-10 cfu 25 g-1), provided negative and presumptive positive results ...	2000	10792548
treatment of sanitary-important bacteria by bacteriocin substance v24 in cattle dung water.	quantification of sanitary-important bacteria (e.g. enterobacteriaceae), as well as indicators of environmental contamination, was assessed in samples of cattle dung from 25 cattle farms in 15 north-eastern slovakia districts. the inhibitory effect of crude bacteriocin extract cbe v24 from enterococcus faecalis v24 against listeria monocytogenes ohio and yersinia enterocolitica ye85 was examined in cattle dung water with the aim of finding a new way of eliminating the health risk of the animal s ...	2000	10792671
prfa mediates specific binding of rna polymerase of listeria monocytogenes to prfa-dependent virulence gene promoters resulting in a transcriptionally active complex.	there is accumulating evidence that the coordinate transcription of the virulence genes in listeria monocytogenes constitutes a very complex regulation mechanism which might require other factors in addition to prfa. we previously described an unknown proteinaceous component from crude bacterial cell extracts, which, together with prfa, formed a specific complex (ci) in electrophoretic mobility shift assays (emsa) with an hly promoter probe. here we identify the rna polymerase (rnap) of l. monoc ...	2000	10792734
the use of listeriolysin to identify in vivo induced genes in the gram-positive intracellular pathogen listeria monocytogenes.	listeria monocytogenes is capable of growth within the cytoplasm of infected host cells. escape from the host cell phagosome is mediated primarily through secretion of listeriolysin, a haemolytic factor which functions to actively lyse the phagosomal membrane. listeriolysin negative mutants of l. monocytogenes are non-haemolytic on blood agar plates and demonstrate a significant reduction of virulence in the mouse model of infection. we have developed a system for the identification of in vivo i ...	2000	10792735
characterization of the interaction between zyxin and members of the ena/vasodilator-stimulated phosphoprotein family of proteins.	zyxin contains a proline-rich n-terminal domain that is similar to the c-terminal domain in the acta protein of the bacteria, listeria monocytogenes. we screened the entire amino acid sequence of human zyxin for mena-interacting peptides and found that, as with acta, proline-rich sequences were the sole zyxin sequences capable of binding to ena/vasodilator-stimulated phosphoprotein (vasp) family members in vitro. from this information, we tested zyxin mutants in which the proline-rich sequences ...	2000	10801818
high susceptibility to bacterial infection, but no liver dysfunction, in mice compromised for hepatocyte nf-kappab activation.	based on the essential involvement of nf-kappab in immune and inflammatory responses and its apoptosis-rescue function in normal and malignant cells, inhibitors of this transcription factor are potential therapeutics for the treatment of a wide range of diseases, from bronchial asthma to cancer. yet, given the essential function of nf-kappab in the embryonic liver, it is important to determine its necessity in the liver beyond embryogenesis. nf-kappab is normally retained in the cytoplasm by its ...	2000	10802715
the trophoblast is a component of the innate immune system during pregnancy.	systemic infection with listeria monocytogenes, a gram-positive intracellular bacterium, has been used extensively to analyze the innate immune response. macrophages are central to this response, acting as both the host for and principal defense against this bacterium. during pregnancy l. monocytogenes has a predilection for replication at the maternal-placental interface and consequently is an important cause of fetal morbidity and mortality. however, macrophages are mostly excluded from the mu ...	2000	10802718
influence of catalase and superoxide dismutase on ozone inactivation of listeria monocytogenes.	the effects of ozone at 0.25, 0.40, and 1.00 ppm on listeria monocytogenes were evaluated in distilled water and phosphate-buffered saline. differences in sensitivity to ozone were found to exist among the six strains examined. greater cell death was found following exposure at lower temperatures. early stationary-phase cells were less sensitive to ozone than mid-exponential- and late stationary-phase cells. ozonation at 1.00 ppm of cabbage inoculated with l. monocytogenes effectively inactivate ...	2000	10742219
significance of inoculum size in the lag time of listeria monocytogenes.	the lag time of listeria monocytogenes growing under suboptimal conditions (low nutrient concentrations, ph 6, and 6.5 degrees c) was extended when the inoculum was severely stressed by starvation and the inoculum size was very small. predictive microbiology should deal with bacterial stress and stochastic approaches to improve its value for the agro-food industry.	2000	10742265
outbreak of listeria monocytogenes serovar 4b infection in france.		2000	10743331
local activation of nonspecific defense against a respiratory model infection by application of interferon-gamma: comparison between rat alveolar and interstitial lung macrophages.	pulmonary macrophages play a crucial role in the defense of inhaled pathogens. we characterized functional properties of alveolar (am) and interstitial (im) macrophages from rats. am exhibited a pronounced microbicidal capacity as shown by an elevated production of reactive oxygen intermediates (roi), nitric oxide (no), tumor necrosis factor (tnf)-alpha, and tumor cytotoxicity when compared with im. in contrast, im were superior to am regarding mechanisms mainly involved in the induction and mai ...	2000	10745029
inhibitory combinations of nisin, sodium chloride, and ph on listeria monocytogenes atcc 15313 in broth by an experimental design approach.	the influence of ph (5.0-8.2), nacl concentrations (0-6% w/v), and incubation time (0-24 h) on the inhibitory activity of nisin (0-100 i.u./ml) against listeria monocytogenes (10(3) cfu/ml) was studied using the doehlert experimental design and was confirmed by kinetic experiments. predicted values were in agreement with experimental values. experiments were carried out at 22 degrees c in reconstituted tsb-ye1 broth with or without nacl. nisin had an immediate ph-dependent bactericidal effect, w ...	2000	10746580
identification of new loci involved in adhesion of listeria monocytogenes to eukaryotic cells. european listeria genome consortium.	insertional mutagenesis was performed with tn1545 in the genetic background of an iniab deletion mutant to identify new adhesion determinants in listeria monocytogenes. four insertion mutants defective in adhesion to eukaryotic cells were identified. insertion sites were cloned by inverse-pcr and sequenced. the genetic organization of insertion regions was further analysed by screening and sequencing dna fragments from a hindiii library and by searching databases. three adhesion-defective mutant ...	2000	10746777
gc1q-r/p32, a c1q-binding protein, is a receptor for the inlb invasion protein of listeria monocytogenes.	inlb is a listeria monocytogenes protein that promotes entry of the bacterium into mammalian cells by stimulating tyrosine phosphorylation of the adaptor proteins gab1, cbl and shc, and activation of phosphatidyl- inositol (pi) 3-kinase. using affinity chromatography and enzyme-linked immunosorbent assay, we demonstrate a direct interaction between inlb and the mammalian protein gc1q-r, the receptor of the globular part of the complement component c1q. soluble c1q or anti-gc1q-r antibodies impai ...	2000	10747014
acting like actin. the dynamics of the nematode major sperm protein (msp) cytoskeleton indicate a push-pull mechanism for amoeboid cell motility.		2000	10747081
improvement of the detection of listeria monocytogenes by the application of aloa, a diagnostic, chromogenic isolation medium.	a new selective agar medium, aloa, for the selective and differential isolation of listeria monocytogenes has been evaluated. all stressed cultures of l. monocytogenes serovars tested grew on the medium as bluish colonies surrounded by a distinctive opaque halo and gave a productivity ratio of at least 0.95. non-pathogenic listeria sp. produced bluish colonies without a halo as was also the case for some enterococci and bacilli. special attention must be paid to some bacillus cereus strains and ...	2000	10747223
anti-listeria effect of enterocin a, produced by cheese-isolated enterococcus faecium efm01, relative to other bacteriocins from lactic acid bacteria.	enterocin a produced by enterococcus faecium efm01 displayed a narrow antimicrobial spectrum, mainly directed against listeria spp. in particular, the bacteriocin was extremely active against 13 listeria monocytogenes strains. this high specificity of action of enterocin a for listeria spp. relative to lactic acid bacteria, together with its broad range of activity from ph 4.0 to ph 9.0, are factors which may be of great interest with respect to the potential antilisterial use of this bacterioci ...	2000	10747225
the growth and resistance to sodium hypochlorite of listeria monocytogenes in a steady-state multispecies biofilm.	a constant-depth film fermenter (cdff) was used to culture a steady-state multispecies biofilm consisting of one strain each of listeria monocytogenes, pseudomonas fragi and staphylococcus xylosus. these bacteria were initially grown together in a conventional chemostat to achieve a steady state before being inoculated into the cdff over an 18-h period. a dilute tryptone soya broth (tsb) medium was supplied to the cdff and the biofilm allowed to develop over a 28-d period. this mature biofilm wa ...	2000	10747232
variations in virulence between different electrophoretic types of listeria monocytogenes.	a total of 245 strains of listeria monocytogenes, representing 33 different electrophoretic types (ets), were examined quantitatively for haemolytic activity. no significant difference was observed in the mean haemolytic activity between different ets. eighty four out of 91 strains examined were found to be virulent for chick embryos. strains belonging to et 2 and et 4 were found to be less virulent than strains of other ets (p = 0.0447). furthermore, strains from clinical cases were found to be ...	2000	10747256
activity of hydrolysed lactoferrin against foodborne pathogenic bacteria in growth media: the effect of edta.	lactoferrin was hydrolysed with pepsin and the antimicrobial activity of the resulting hydrolysate (hlf) was studied in 1% peptone, 0.05% yeast extract, 1% glucose (pyg) medium and tryptic soy broth (tsb). hlf was effective against listeria monocytogenes, enterohaemorrhagic escherichia coli and salmonella enteritidis in pyg, however, the highest studied concentration (1.6 mg ml-1) did not inhibit growth of any of these organisms in tsb. the addition of edta enhanced the activity of hlf in tsb, i ...	2000	10747257
sensitivity of nisin-resistant listeria monocytogenes to heat and the synergistic action of heat and nisin.	nisin, a bacteriocin produced by some strains of lactococcus lactis, acts against foodborne pathogen listeria monocytogenes. a single exposure of cells to nisin can generate nisin-resistant (nisr) mutants, which may compromise the use of nisin in the food industry. the objective of this research was to compare the heat resistance of nisr and wild type (wt) listeria monocytogenes. the synergistic effect of heat-treatment (55 degrees c) and nisin (500 iu ml-1) on the nisr cells and the wt l. monoc ...	2000	10747260
[listeria monocytogenes endocarditis of a prosthetic valve].		2000	10734764
listeriosis, france.		2000	10734782
listeria monocytogenes septicemia in a thoroughbred foal.	listeria monocytogenes septicemia was diagnosed in a 6-day-old thoroughbred foal. primary clinical signs included fever, depression, diarrhea, and respiratory distress. hematologic abnormalities included leukopenia, neutropenia, degenerative left shift, and hyperfibrinogenemia. clinical chemistry and blood gas abnormalities included metabolic acidosis, hypoxemia, hypocapnia, hypoglycemia, and hyponatremia. despite aggressive therapeutic intervention and intensive care, the foal died within 12 ho ...	2000	10730952
ctsr controls class iii heat shock gene expression in the human pathogen listeria monocytogenes.	stress proteins play an important role in virulence, yet little is known about the regulation of stress response in pathogens. in the facultative intracellular pathogen listeria monocytogenes, the clp atpases, including clpc, clpp and clpe, are required for stress survival and intracellular growth. the first gene of the clpc operon of l. monocytogenes encodes a homologue of the bacillus subtilis ctsr repressor of stress response genes. an l. monocytogenes ctsr-deleted mutant displayed enhanced s ...	2000	10692157
growing an actin gel on spherical surfaces.	inspired by the motility of the bacteria listeria monocytogenes, we have experimentally studied the growth of an actin gel around spherical beads grafted with acta, a protein known to be the promoter of bacteria movement. on acta-grafted beads f-actin is formed in a spherical manner, whereas on the bacteria a "comet-like" tail of f-actin is produced. we show experimentally that the stationary thickness of the gel depends on the radius of the beads. moreover, the actin gel is not formed if the ac ...	2000	10692348
rapid determination of listeria monocytogenes by automated enzyme-linked immunoassay and nonradioactive dna probe.	a rapid and reliable analytical method was developed to detect and confirm the presence of listeria monocytogenes in raw and partially processed foods. forty-nine food samples (25 mixed cut vegetable salad, 12 smoked salmon, and 12 sterile smoked salmon) were individually inoculated with high levels [10-100 colony forming units (cfu)/25 g sample] and low levels (1-10 cfu/25 g sample) of l. monocytogenes, and were screened using the vitek immuno diagnostic assay (vidas) listeria monocytogenes (vi ...	2000	10693007
the macrocyclic peptide antibiotic micrococcin p(1) is secreted by the food-borne bacterium staphylococcus equorum ws 2733 and inhibits listeria monocytogenes on soft cheese.	staphylococcus equorum ws 2733 was found to produce a substance exhibiting a bacteriostatic effect on a variety of gram-positive bacteria. the metabolite was purified to homogeneity by ammonium sulfate precipitation and semipreparative reversed-phase high-performance liquid chromatography. electrospray mass spectrometry confirmed the high purity of the compound and revealed a molecular mass of 1,143 da. by two-dimensional nuclear magnetic resonance spectroscopy the substance was identified as mi ...	2000	10831414
in vitro and in vivo macrophage function can occur independently of slp-76.	expression of sh2 domain-containing leukocyte-specific phosphoprotein of 76 kda (slp-76), a hematopoietic cell-specific adapter protein, is required to couple syk family tyrosine kinase activation to downstream mediators such as phospholipase c (plc)-gamma following tcr, platelet collagen receptor and mast cell fc epsilon r stimulation. in addition to t cells, mast cells and platelets, slp-76 is expressed in monocytes and macrophages. to determine the role of slp-76 in fc gamma r-stimulated sign ...	2000	10837416
transcription-coupled and global genome repair differentially influence uv-b-induced acute skin effects and systemic immunosuppression.	exposure to uv-b radiation impairs immune responses in mammals by inhibiting especially th1-mediated contact hypersensitivity and delayed-type hypersensitivity. immunomodulation is not restricted to the exposed skin, but is also observed at distant sites, indicating the existence of mediating factors such as products from exposed skin cells or photoactivated factors present in the superficial layers. dna damage appears to play a key role, because enhanced nucleotide excision repair (ner) strongl ...	2000	10843671
adaptive immunity and enhanced cd8+ t cell response to listeria monocytogenes in the absence of perforin and ifn-gamma.	single ag-specific cd8+ t cells from ifn-gamma-deficient (gko) or perforin-deficient (pko) mice provide substantial immunity against murine infection with listeria monocytogenes. to address the potential for redundancy between perforin and ifn-gamma as cd8+ t cell effector mechanisms, we generated perforin/ifn-gamma (pko/gko) double-deficient mice. pko/gko-derived cd8+ t cells specific for the immunodominant listeriolysin o (llo91-99) epitope provide immunity to lm infection similar to that prov ...	2000	10843700
restriction fragment differential display of pediocin-resistant listeria monocytogenes 412 mutants shows consistent overexpression of a putative beta-glucoside-specific pts system.	pediocin pa-1, which is a bacteriocin produced by lactic acid bacteria, has potential as a biopreservative of food. however, such use may lead to the development of resistance in the target organism. gene expression in two independent pediocin-resistant mutants of listeria monocytogenes 412 was compared to the original isolate by restriction fragment differential display pcr (rfdd-pcr). this method amplifies cdna restriction fragments under stringent pcr conditions, enabled by the use of specifi ...	2000	10846216
predictive models of the combined effects of curvaticin 13, nacl and ph on the behaviour of listeria monocytogenes atcc 15313 in broth.	thirty-three strains of listeria monocytogenes belonging to different serotypes were tested for their sensitivity to curvaticin 13, an antilisterial bacteriocin produced by lactobacillus curvatus sb13, using the well diffusion method in institut pasteur agar plates at 37 degrees c. no relationship between serotype and sensitivity was observed. the sensitivity of this species was strain-dependent and a large variation in tolerance to curvaticin 13 was observed. the combined effects of curvaticin ...	2000	10849167
physicochemical surface properties of five listeria monocytogenes strains from a pork-processing environment in relation to serotypes, genotypes and growth temperature.	physicochemical surface properties, related to electrostatic, van der waals and lewis acid-base interactions, of five listeria monocytogenes strains isolated from pork-processing environments were determined after two subcultures at 37 degrees c and a final culture at three temperatures: 37, 10 and 4 degrees c. three strains (lm1, lm114 and lm191) were genetically related while two were unrelated (lm25 and lm74) according to apai-macrorestriction and pulsed-field gel electrophoresis (pfge) typin ...	2000	10849175
solubility and antimicrobial efficacy of protamine on listeria monocytogenes and escherichia coli as influenced by ph.	the antimicrobial efficacy of protamine on listeria monocytogenes and escherichia coli was evaluated at concentrations from 50 to 10 000 microgram ml-1 and ph levels from 5.5 to 8.0. the minimum inhibitory concentrations decreased with increasing ph. protamine inhibited e. coli at all ph values while l. monocytogenes was inhibited at ph 6.5 and above. the antimicrobial efficacy of protamine decreased in the presence of negatively charged gelatine b but remained almost unchanged with addition of ...	2000	10849181
survey for psychrotrophic bacterial pathogens in minimally processed lettuce.	a total of 120 minimally processed, cut and packaged lettuce samples were purchased from retail supermarkets or provided by a salad production facility over an 8-month period. the samples were tested for total aerobic plate counts and for the presence of potentially pathogenic species belonging to the genera of listeria, aeromonas and yersinia. the aerobic plate counts ranged from 103 to 109 colony forming units (cfu) g-1. most samples (76%) contained between 105 and 107 cfu g-1 total aerobic ba ...	2000	10849276
a comparison of the bioscreen method and microscopy for the determination of lag times of individual cells of listeria monocytogenes.	lag phase durations (tlag) of individual listeria monocytogenes cells were analysed using the nightowl molecular imaging system, and results were compared with mean individual cell lag times (tl) obtained from the detection time (td) method using bioscreen. with bioscreen, an average tl of 6.39+/-0.89 h was obtained from five separate experiments. with the nightowl method, an average tlag of 2.73+/-0.06 h was obtained from three experiments consisting of eight total replicates. lag values from t ...	2000	10849278
pulsed-field gel electrophoresis for the analysis of listeria monocytogenes infection clusters after kidney transplantation.	listeria monocytogenes causes a rare, life-threatening infection in recipients of transplanted organs. we used cultures of blood and cerebrospinal fluid to characterize isolates and to distinguish cases in clusters from what might have been sporadic cases. from december 1994 to november 1995, six systemic l. monocytogenes infections occurred at our renal-transplantation unit. we confirmed the clinical diagnosis with blood and cerebrospinal fluid cultures and characterized the isolates retrospect ...	2000	10850630
treatment of listeriosis.	to review the most currently accepted treatment options for the treatment of listeriosis.	2000	10852095
survival of listeria innocua in salmon following cold-smoke application.	the ability of listeria innocua to survive on salmon fillets during cold smoking in a commercial processing plant was investigated using a central composite rotatable response surface design to examine smoking temperatures in the range of 18 to 30 degrees c and a smoke time from 2 to 14 h. smoke temperature did not significantly (p < 0.05) reduce counts of l. innocua on the salmon. however, the smoking time had a significant effect on l. innocua. the smoking time was directly related to the redu ...	2000	10852563
antibacterial mechanism of allyl isothiocyanate.	allyl isothiocyanate (aitc), a natural compound in plants belonging to the family cruciferae, has been shown to have strong antimicrobial activity in liquid media as well as in its vapor form. to understand its antimicrobial mechanism, aitc was tested for bactericidal activities to salmonella montevideo, escherichia coli o157:h7, and listeria monocytogenes scott a at different stages of growth and was compared with streptomycin, penicillin g, and polymyxin b, each of known antibacterial mechanis ...	2000	10852565
antibacterial activity of a chitooligosaccharide mixture prepared by cellulase digestion of shrimp chitosan and its application to milk preservation.	the antibacterial activity of a chitooligosaccharide mixture prepared by digestion of shrimp chitosan with cellulase at 50 degrees c for 14 h was evaluated. sugars with 1 to 8 degrees of polymer (dp) were found in this chitooligosaccharide mixture, and the weight percentage of sugars with dp > or = 6 was 44.3%. minimal lethal concentrations of this mixture against aeromonas hydrophila, escherichia coli, listeria monocytogenes, pseudomonas aeruginosa, salmonella typhimurium, shigella dysenteriae, ...	2000	10852568
a multidrug efflux transporter in listeria monocytogenes.	a chromosomal gene (mdrl) was found in listeria monocytogenes l028, showing a high degree of similarity with multidrug efflux transporters of the major facilitator superfamily (family 2). an allele-substituted mutant of this gene failed to pump out ethidium bromide and presented lower minimal inhibitory concentrations of macrolides, cefotaxime and heavy metals. this is the first multidrug efflux pump described in listeria.	2000	10856655
survival characteristics and the applicability of predictive mathematical modelling to listeria monocytogenes growth in sous vide products.	survival and growth of listeria monocytogenes isolates during sous vide processing and storage, and the applicability of predictive modelling in determining the potential for growth of l. monocytogenes in broth models and in sous vide products was investigated. l. monocytogenes grew in anaerobic tryptose phosphate broth and in chicken and beef samples by 2 log cycles in 8 days at 3 degrees c and 4-5 log cycles in 6 days at 8 degrees c. however, heating to an internal temperature of 70 degrees c ...	2000	10857538
survival of osmotic and acid stress by listeria monocytogenes strains of clinical or meat origin.	the ability of 30 listeria monocytogenes strains, 15 of meat origin and 15 of clinical origin, to use carnitine as an osmoprotectant and to resist acid stress was determined. all strains examined were able to use carnitine as an osmoprotectant, indicating the importance of this characteristic to the survival of l. monocytogenes in natural environments. clinical and meat strains, however, differed with respect to this characteristic. specifically, 73% of meat strains reached a lower maximum cell ...	2000	10857542
combined pcr and slot blot assay for detection of salmonella and listeria monocytogenes.	detection of salmonella typhimurium and listeria monocytogenes by the polymerase chain reaction (pcr) assay coupled with slot blot detection was investigated in this study. after being extracted from diluted bacterial culture with the extraction buffer, bacterial dna was subjected to pcr. the slot blot assay was optimized and used to detect pcr products. the lowest detection level of this method was 10(3) cfu/ml in the original culture media for both pathogens, or 5 bacterial cells in the pcr re ...	2000	10857543
a new rapid automated method for the detection of listeria from environmental swabs and sponges.	many food and meat processors test environmental swabs and sponges to confirm the absence of listeria spp. spectral pattern changes in a liquid growth medium, resulting from esculin hydrolysis by listeria in contaminated swabs and sponges, were automatically monitored by the biosys instrument in a semifluid layer (sfl). the blackening of sfl in modified mox broth resulted in sharply declining curves, which were easily detected by the instrument. the instrument detected all nine strains of lister ...	2000	10857550
mathematical modelling of the growth rate and lag time for listeria monocytogenes.	growth data for listeria monocytogenes were collected from the literature and a global model built with existing secondary models describing independently the effects of environmental factors on the growth rate and lag time was based on these data. the growth rates calculated with this model were consistent with the published ones but the fit was poor near the limits of growth of the micro-organism. the model was also less accurate to describe the lag time. it seems then that reliable prediction ...	2000	10857924
modelling the growth rate of listeria monocytogenes with a multiplicative type model including interactions between environmental factors.	a multiplicative secondary model previously published to describe independently the effects of environmental factors on the growth rate of listeria monocytogenes (augustin and carlier, 2000) was improved by taking into account interactions between these environmental factors. the proposed model allowed to decrease the rate of fail-safe growth predicted from 13.5% to 12.1% and the rate of fail-dangerous no growth predicted from 16.1% to 7.1%.	2000	10857925
host resistance to listeria monocytogenes infection is enhanced but resistance to staphylococcus aureus infection is reduced in acute graft-versus-host disease in mice.	acute graft-versus-host disease (gvhd) is characterized by the production of high levels of t helper 1 (th1)-type cytokines. bone marrow transplantation from allogeneic c57bl/6 cells to cbf(1) mice produced acute gvhd. host resistance to th1-driven listeria monocytogenes was enhanced, whereas host resistance to th2-driven staphylococcus aureus was reduced during acute gvhd. these results suggest that opposite host responses are observed between th1-driven and th2-driven bacterial infections in a ...	2000	10858256
downmodulation of the inflammatory response to bacterial infection by gammadelta t cells cytotoxic for activated macrophages.	although gammadelta t cells are involved in the regulation of inflammation after infection, their precise function is not known. intraperitoneal infection of t cell receptor (tcr)-delta(-/-) mice with the intracellular bacterium listeria monocytogenes resulted in the development of necrotic foci in the livers. in contrast, the peritoneal cavities of infected tcr-delta(-/-) mice contained an accumulation of low density activated macrophages and a reduced percentage of macrophages undergoing apopt ...	2000	10859339
detection of dna via an ion channel switch biosensor.	detection of dna by an ion channel switch biosensor has been demonstrated in a model system, using single-stranded oligonucleotide sequences of 52-84 bases in length. two different biotinylated probes are bound, via streptavidin, either to the outer region of a gramicidin ion channel dimer or to an immobilized membrane component. the ion channels are switched off upon detection of dna containing complementary epitopes to these probes, separated by a nonbinding region, at nanomolar levels. the dn ...	2000	10860501
cutting edge: antilisterial activity of cd8+ t cells derived from tnf-deficient and tnf/perforin double-deficient mice.	the mechanisms by which cd8+ t cells mediate immunity against bacterial pathogens remain largely unknown. perforin-dependent cytolysis plays a role, but is not required for cd8+ t cell-mediated immunity against listeria monocytogenes. tnf is essential for cd8+ t cell immunity to l. monocytogenes, but the cellular source of tnf is undefined. tnf-deficient and tnf/perforin double-deficient mice were used to generate cd8+ t cells specific for an l. monocytogenes-derived ag. wild-type and tnf-defici ...	2000	10861027
use of a ground beef model to assess the effect of the lactoperoxidase system on the growth of escherichia coli o157:h7, listeria monocytogenes and staphylococcus aureus in red meat.	the ability to preserve food in a state that is both appetising and nutritious is a basic requirement for health. food poisoning represents a major source of illness and loss of productivity in many developed countries. of particular concern in recent years are outbreaks of food poisoning associated with escherichia coli o157:h7 or listeria monocytogenes, many of which have been associated with the consumption of ground meat. many of the chemicals presently licensed for use as food preservatives ...	2000	10868676
a model describing the effect of temperature history on lag time for listeria monocytogenes.	a model was built to describe the influence of the temperature and the duration of pre-incubation on the lag time for regrowth of listeria monocytogenes at low temperature. this model is consistent with the usual procedure used to calculate lag times of cultures growing under fluctuating temperatures. it also describes the effect of prolonged starvation conditions on the regrowth lag time and takes into account the influence of the physiological state of inocula in predictive models.	2000	10868678
evaluation of a monoclonal antibody able to detect live listeria monocytogenes and listeria innocua.	a monoclonal listeria antibody, designated b4, was evaluated. the ability of the antibody to bind to viable bacteria belonging to listeria spp. compared to bacteria of the same species killed by heat treatment, acid or base treatment, sanitizers, and irradiation was examined. the antibody was found to react with viable l. monocytogenes and l. innocua, but not with heat-killed (72 degrees c, 5 min) strains of these organisms. when l. monocytogenes and l. innocua were killed by methods other than ...	2000	10868683
microbiologic features of adult community-acquired bacterial meningitis in taiwan.	community-acquired bacterial meningitis (cabm) is a life-threatening disease that requires prompt initiation of appropriate antibiotic therapy. the purpose of this study was to determine the causative microorganisms of cabm and their antimicrobial susceptibility patterns at a major teaching hospital in taipei from 1993 to 1998.	2000	10870313
characterization of iap gene in listeria monocytogenes strains isolated in japan.	variation of the iap gene region (407bp) encoding an invasion-associated protein p60 was studied on 12 strains of listeria monocytogenes of different origin in japan. these 12 strains are known to have 2 types of serotype (1/2a and 4b) and have a diversity among the strains (saito et al., 1998). the dye-primer cycle sequencing method was employed to determine the genomic structure, and the nucleotide sequences obtained were compared with those of reference strain sv 1/2a egd. differences found i ...	2000	10872686
differences in interleukin-12 and -15 production by dendritic cells at the early stage of listeria monocytogenes infection between balb/c and c57 bl/6 mice.	the mechanisms responsible for the resistance of c57bl/6 mice and for the susceptibility of balb/c mice to infection with listeria monocytogenes were studied by comparing early il-12 and il-15 production by dendritic cells (dc) after infection with l. monocytogenes. splenic dc expressing cd11b(low) and cd11c(+) obtained from c57bl/6 mice at 3 and 6 h after l. monocytogenes infection expressed higher levels of il-12 p40 mrna and il-12 p40 protein than did those from balb/c mice. concurrently, a l ...	2000	10873304
the presence of intragenically located rep-like elements in bacillus sporothermodurans is sufficient for rep-pcr typing.	the technique of repetitive extragenic palindromic polymerase chain reaction (rep-pcr) enables the identification and discrimination of clonally related bacillus sporothermodurans isolates from ultra-high temperature and sterilized milk. the aim of this study was to investigate the genetic basis for the generation of these highly informative rep-pcr patterns. the major 947-bp rep-pcr fragment of b. sporothermodurans was cloned, together with its 5' and 3' flanking sequences. only partial homolog ...	2000	10875282
listeria monocytogenes peritonitis: an unusual presentation and review of the literature.	listeria monotogenes bacteria-ascites developed in a 73-year-old man who had cholangiocarcinoma and liver metastasis. spontaneous bacterial peritonitis (sbp) is a frequent complication in patients with chronic liver disease and ascites. l. peritonitis has been reported in only <30 cases world-wide. our patient represents a unique case of l. peritonitis without peritoneal fluid analysis consistent with spontaneous bacteria peritonitis. however, the culture of the ascitic fluid provided the final ...	2000	10875476
[the interaction of yersinia, listeria and salmonella with plant cells].	the results of the interaction of bacteria of the genera yersinia, listeria and salmonella, pathogenic for humans and animals, with callus cultures of different plant species are presented. as revealed in this study, complicated interactions developed between bacteria and plant cells. plant cells were shown to be highly sensitive to the action of bacteria. yersinia, listeria and salmonella were found to be capable of callus damage. the influence of plant cells on bacteria was more complicated: b ...	2000	10876881
[nutrient media for the isolation and accumulation of listeria].	dried culture media for the isolation and accumulation of listeria from pathological material and foodstuffs have been developed. the media are suitable for use in bacteriological and sanitary-hygienic practice. the optimum nutrient base has been selected: dried broth (from sprat hydrolysate), produced by the research and manufacturing amalgamation "culture media". the optimum concentrations of ingredients, stimulating the growth of listeria and inhibiting the growth of associated microbes, have ...	2000	10876892
measurement of the elasticity of the actin tail of listeria monocytogenes.	we report biophysical experiments performed on the bacterium listeria monocytogenes, a model system to study actin-based motility. using optical tweezers and electrophoresis experiments, we find that the bacterium is firmly attached to its tail, and we demonstrate that the tail responds as an elastic gel when deformed. we have measured its elastic modulus at a value of 10(3)-10(4) pa, which is 10 times higher than the rigidity of the eukaryotic cytoplasm. these results demonstrate that the bacte ...	2000	10877022
gene cloning and expression and secretion of listeria monocytogenes bacteriophage-lytic enzymes in lactococcus lactis.	bacteriophage lysins (ply), or endolysins, are phage-encoded cell wall lytic enzymes which are synthesized late during virus multiplication and mediate the release of progeny virions. bacteriophages of the pathogen listeria monocytogenes encode endolysin enzymes which specifically hydrolyze the cross-linking peptide bridges in listeria peptidoglycan. ply118 is a 30.8-kda l-alanoyl-d-glutamate peptidase and ply511 (36.5 kda) acts as n-acetylmuramoyl-l-alanine amidase. in order to establish dairy ...	2000	10877791
absence of a putative mannose-specific phosphotransferase system enzyme iiab component in a leucocin a-resistant strain of listeria monocytogenes, as shown by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis.	leucocin a is a class iia bacteriocin produced by leuconostoc spp. that has previously been shown to inhibit the growth of listeria monocytogenes. a spontaneous resistant mutant of l. monocytogenes was isolated and found to be resistant to leucocin a at levels in excess of 2 mg/ml. the mutant showed no significant cross-resistance to nontype iia bacteriocins including nisaplin and esf1-7gr. however, there were no inhibition zones found on a lawn of the mutant when challenged with an extract cont ...	2000	10877813
virulent rough filaments of listeria monocytogenes from clinical and food samples secreting wild-type levels of cell-free p60 protein.	atypical rough cell filaments of listeria monocytogenes (designated fr variants), isolated from clinical and food samples, form long filaments up to 96 microm in length and demonstrated wild-type levels of adherence, invasion, and cytotoxicity to human epithelial hep-2, caco-2, and hela cells. unlike previously described avirulent rough mutants of l. monocytogenes that secrete diminished levels of the major extracellular protein p60 and that form long chains that consist of multiple cells of sim ...	2000	10878057
a novel beta-glucoside-specific pts locus from streptococcus mutans that is not inhibited by glucose.	a regulon from streptococcus mutans that plays a role in the utilization of beta-glucosides has been isolated, sequenced and subjected to sequence analysis. this regulon encodes a beta-glucoside-specific enzyme ii (eii) component (bglp) of the phosphoenolpyruvate-dependent phosphotransferase system (pts) and a phospho-beta-glucosidase (bgla) which is responsible for the breakdown of the phospho-beta-glucosides within the cell. both the bglp and bgla gene products have significant similarity with ...	2000	10878120
the arp2/3 complex branches filament barbed ends: functional antagonism with capping proteins.	the arp2/3 complex is an essential regulator of actin polymerization in response to signalling and generates a dendritic array of filaments in lamellipodia. here we show that the activated arp2/3 complex interacts with the barbed ends of filaments to initiate barbed-end branching. barbed-end branching by arp2/3 quantitatively accounts for polymerization kinetics and for the length correlation of the branches of filaments observed by electron microscopy. filament branching is visualized at the su ...	2000	10878802
exploiting the immune system: toward new vaccines against intracellular bacteria.		2000	10879281
amplified fragment length polymorphism (aflp) analysis of listeria monocytogenes.	aflp analysis using four selective primers was performed on a set of 33 listeria monocytogenes including strains from patients and foods implicated in outbreaks, human sporadic cases or foods. strains were tested belonging to serovars 1/2a, 1/2b, 1/2c, 3b, and 4b. using one of the primers, the aflp technique generated 20 different sized dna fragments. the 33 cultures segregated into 14 different patterns, each comprising 7-12 different fragments. although the method was not sufficiently discrimi ...	2000	10879987
from hot dogs to cd8+ t cells: listeria monocytogenes.		2000	10881333
a novel antibacterial agent derived from the c-terminal domain of streptococcus mutans gtp-binding protein.	a decapeptide, p1, homologous to part of the streptococcus mutans g-protein (sgp) and the escherichia coli era protein, was synthesized and examined for growth-inhibitory effects. when p1 10 mg/l was added to e. coli dh5, the viability of the cells was reduced by 13%. addition of lauric acid enhanced the bactericidal effects of p1 (68% killing in the presence of p1 plus lauric acid). similar enhancements were observed for mono lauroyl-rac-glycerol (mlg) and sodium dodecyl sulphate (sds). in cult ...	2000	10882696
pathogen-specific loss of host resistance in mice lacking the ifn-gamma-inducible gene igtp.	interferon-gamma (ifn-gamma) is critical for defense against pathogens, but the molecules that mediate its antimicrobial responses are largely unknown. igtp is the prototype for a family of ifn-gamma-regulated genes that encode 48-kda gtp-binding proteins that localize to the endoplasmic reticulum. we have generated igtp-deficient mice and found that, despite normal immune cell development and normal clearance of listeria monocytogenes and cytomegalovirus infections, the mice displayed a profoun ...	2000	10639151
mutants of listeria monocytogenes defective in in vitro invasion and cell-to-cell spreading still invade and proliferate in hepatocytes of neutropenic mice.	listeria monocytogenes mutants defective in the acta gene, the plcb gene, and the inla and inlb genes were less virulent when injected intravenously into balb/c mice. the growth of these strains as well as of the virulent wild-type strains was increased by treating mice with a neutrophil-specific depleting monoclonal antibody, rb6-8c5. histologic examination of the livers of the treated animals showed intrahepatocytic proliferation of the listeriae in all cases. our data show that more than one ...	2000	10639462
role of listeriolysin o in cell-to-cell spread of listeria monocytogenes.	listeria monocytogenes is a facultative intracellular bacterial pathogen that escapes from a host vacuolar compartment and grows rapidly in the cytosol. listeriolysin o (llo) is a secreted pore-forming protein essential for the escape of l. monocytogenes from the vacuole formed upon initial internalization. however, its role in intracellular growth and cell-to-cell spread events has not been testable by a genetic approach. in this study, purified six-his-tagged llo (hisllo) was noncovalently cou ...	2000	10639481
determination of natural resistance of mice fed dietary lipids to experimental infection induced by listeria monocytogenes.	current understanding based on the effect of dietary lipid manipulation upon immune system function indicates that fatty acids are involved in the modulation of the immune response through different and complex pathways. reduction of several immune parameters by fatty acid action may be applied in the treatment of diseases characterised by an overactivation of the immune system. as a consequence, a reduction of host resistance against infectious agents has been reported in animals fed dietary li ...	2000	10640607
bactericidal activity of isothiocyanate against pathogens on fresh produce.	the bactericidal activity of allyl and methyl isothiocyanate (aitc and mitc) was tested with a rifampicin-resistant strain of salmonella montevideo and streptomycin-resistant strains of escherichia coil o157:h7 and listeria monocytogenes scott a. iceberg lettuce inoculated with high (10(7) to 10(8) cfu/g) and low (10(3) to 10(4) cfu/g) concentrations of bacterial pathogens was treated with aitc and mitc in sealed containers at 4 degrees c for 4 days. aitc showed stronger bactericidal activity th ...	2000	10643765
survival of listeria monocytogenes scott a on vacuum-packaged raw beef treated with polylactic acid, lactic acid, and nisin.	low-molecular-weight polylactic acid (lmw-pla) and lactic acid (la) were used to inhibit growth of listeria monocytogenes scott a on vacuum-packaged beef. nisin was also used simultaneously as an additional hurdle to the growth of this pathogen. inoculated beef cubes were immersed in a solution of 2% lmw-pla, 2% la, 400 iu/ml of nisin, or combinations of each acid and nisin for 5 min and drip-dried for 15 min. the cubes were then vacuum-packaged and stored at 4 degrees c for up to 42 days. surfa ...	2000	10643784
sequence variations within prfa dna binding sites and effects on listeria monocytogenes virulence gene expression.	reporter gene fusions were used to investigate the contributions of prfa dna binding sites to listeria monocytogenes virulence gene expression. our results suggest that the dna sequence of prfa binding sites determines the levels of expression of certain virulence genes, such as hly and mpl. other virulence genes, such as acta and plcb, may depend upon additional factors for full regulation of gene expression.	2000	10633124
identification and characterization of immunoglobulin g in blood as a major inhibitor of diagnostic pcr.	a major inhibitor of diagnostic pcr in human plasma was identified and the mechanism of inhibition was characterized. human blood was divided by centrifugation into buffy coat, plasma, platelets, and erythrocytes. all these blood fractions were found to be highly inhibitory to a standardized pcr mixture containing the thermostable dna polymerase amplitaq gold. pcr inhibitors in human plasma were purified by chromatographic procedures and were characterized by a process of elimination, so that th ...	2000	10618113
listeria monocytogenes acta protein interacts with phosphatidylinositol 4,5-bisphosphate in vitro.	the n-terminal region of the listeria monocytogenes acta protein, in conjunction with host cell factors, is sufficient for actin polymerization at the bacterial surface. previous data suggested that acta could protect barbed ends from capping proteins. we tested this hypothesis by actin polymerization experiments in the presence of the acta n-terminal fragment and capping protein. acta does not protect barbed ends from capping protein. in contrast, this polypeptide prevents pip(2) from inhibitin ...	2000	10618167
molecular grouping of listeria monocytogenes based on the sequence of the inib gene.	the major part of the gene inlb was sequenced in 24 strains of listeria monocytogenes belonging to serovars 1/2a, 1/2b, 1/2c, 3b and 4b. a phylogenetic analysis based on the inlb nucleotide sequences showed that strains of serovars 1/2a and 1/2c were closely related, as well as those of serovars 1/2b and 3b. strains sharing serovar 4b could be divided into two distinct groups. there were differences in amino-acid sequence between all serovars except between serovars 1/2b and 3b. differences in a ...	2000	10628828
comparative in vitro activity of moxifloxacin against gram-positive clinical isolates.	the in vitro activity of moxifloxacin was compared with that of 15 antibacterial agents against 513 gram-positive microorganisms. the mic(90) (mg/l) of moxifloxacin was 0.06 for quinolone-susceptible staphylococcus aureus and staphylococcus epidermidis, 0.12 for streptococcus pyogenes and streptococcus agalactiae; 0.25 for streptococcus pneumoniae, streptococcus mitis, streptococcus bovis, streptococcus anginosus and actinomyces pyogenes; 0.5 for streptococcus sanguis and listeria monocytogenes, ...	2000	10629010
electron paramagnetic resonance studies of the membrane fluidity of the foodborne pathogenic psychrotroph listeria monocytogenes.	listeria monocytogenes is a foodborne psychrotrophic pathogen that grows at refrigeration temperatures. previous studies of fatty acid profiles of wild-type and cold-sensitive, branched-chain fatty acid deficient mutants of l. monocytogenes suggest that the fatty acid 12-methyltetradecanoic (anteiso-c(15:0)) plays a critical role in low-temperature growth of l. monocytogenes, presumably by maintaining membrane fluidity. the fluidity of isolated cytoplasmic membranes of wild-type (slcc53 and 1040 ...	2000	10631292
th1-biased immune responses induced by dna-based immunizations are mediated via action on professional antigen-presenting cells to up-regulate il-12 production.	the efficacy of dna-based immunization in conferring protective immunity against certain microbial pathogens including human immunodeficiency virus type 1 (hiv-1) has been described. the potential advantage of dna-based immunization over the traditional vaccines largely results from its capacity to efficiently induce th1-biased immune responses against an encoded antigen. we describe how th1-biased immune responses are induced by dna-based immunization, using a dna vaccine construct encoding hiv ...	2000	10606974