Publications

enhanced inhibition of listeria monocytogenes and salmonella enteritidis in meat by combinations of sodium lactate and diacetate.	the antimicrobial activities of sodium lactate (sl) and sodium acetate (sa) are well documented, but there is limited information on the effect of their combination or of the combination of sl and sodium diacetate (sda) on survival and growth of listeria monocytogenes and salmonellae in meat. effects of sl (1.8 and 2.5%), sda (0.1 and 0.2%), or sa (0.2%) and their combinations on the behavior of l monocytogenes and salmonella enterica serovar enteritidis were investigated in sterile comminuted b ...	2001	11347993
random amplified polymorphic dna typing applied to the study of cross-contamination by listeria monocytogenes in processed food products.	the presence of listeria spp. was investigated in 369 samples of cooked meat products and 52 of smoked salmon. incidences of 17.6% for cooked meat and 38.5% for smoked salmon samples were found. all listeria monocytogenes isolates (34 from meat products and 16 from smoked salmon) were typed serologically and by random amplified polymorphic dna (rapd) typing using primers hlwl74 (5'-acgtatctgc-3'), hlwl85 (5'-acaactgctc-3'), and omp-01 (5'-gti'ggtggct-3'). strains from cooked meat products were c ...	2001	11348007
effects of epiphytic enterobacteriaceae and pseudomonads on the growth of listeria monocytogenes in model media.	four enterobacteriaceae (enterobacter agglomerans and rhanella aquatilis) and six pseudomonads (pseudomonas fluorescens, pseudomonas chlororaphis, pseudomonas putida) isolated from minimally processed green endive were coinoculated at 10 degrees c with listeria monocytogenes in a minimal medium. pseudomonads did not modify the growth of l. monocytogenes, whereas enterobacteriaceae reduced its maximal population by 2 to 3 log cfu/ml. the same effect was observed in a diluted yeast extract medium ...	2001	11348008
immunization of mice with lipopeptide antigens encapsulated in novel liposomes prepared from the polar lipids of various archaeobacteria elicits rapid and prolonged specific protective immunity against infection with the facultative intracellular pathogen, listeria monocytogenes.	protective immunity to intracellular bacterial pathogens usually requires the participation of specific cd8+ t cells. natural exposure of the host to sublethal infection, or vaccination with attenuated live vaccines are the most effective means of eliciting prolonged protective cell-mediated immunity against this class of pathogens. the ability to replace these immunization strategies with defined sub-unit vaccines would represent a major advance for clinical vaccinology. the present study exami ...	2001	11348718
gut colonization of mice with acta-negative mutant of listeria monocytogenes can stimulate a humoral mucosal immune response.	we used listeria monocytogenes, a gram-positive, facultative intracellular bacterium, to study the gut mucosal immune responses following oral infection. we employed a germfree (gf) mouse model to try to accentuate the development of a humoral mucosal immune response in the gut, and we used oral colonization with one of the mutants, acta-negative (deltaacta) l. monocytogenes, to restrict infection largely to the gut. the deltaacta mutant was able to colonize the intestinal mucosa of formerly gf ...	2001	11349011
calprotectin expression inhibits bacterial binding to mucosal epithelial cells.	squamous mucosal epithelial cells constitutively express calprotectin in the cytoplasm. to study how this antimicrobial protein complex confers epithelial resistance to invading bacteria, an epithelial cell line was stably transfected to express the calprotectin complex. cells expressing calprotectin resist invasion by listeria monocytogenes and salmonella enterica serovar typhimurium. calprotectin expression was accompanied by altered actin organization, increased alpha3 integrin expression, an ...	2001	11349032
characterization of the groesl operon in listeria monocytogenes: utilization of two reporter systems (gfp and hly) for evaluating in vivo expression.	the ability of intracellular pathogens to sense and adapt to the hostile environment of the host is an important factor governing virulence. we have sequenced the operon encoding the major heat shock proteins groes and groel in the gram-positive food-borne pathogen listeria monocytogenes. the operon has a conserved orientation in the order groes groel. upstream of groes and in the opposite orientation is a gene encoding a homologue of the bacillus subtilis protein ydil, while downstream of groel ...	2001	11349060
gene fragments distinguishing an epidemic-associated strain from a virulent prototype strain of listeria monocytogenes belong to a distinct functional subset of genes and partially cross-hybridize with other listeria species.	most major food-borne outbreaks of listeriosis in europe and in the united states have been caused by genetically closely related listeria monocytogenes strains of serotype 4b. in order to assess whether genomic loci exist that could underlie this increased epidemic potential, we subtracted the genome of the virulent prototype l. monocytogenes strain egd from a prototype epidemic strain. a total of 39 dna fragments corresponding to 20% of an estimated total of 150 to 190 kb of differential genom ...	2001	11349066
nitric oxide is protective in listeric meningoencephalitis of rats.	the bacterium listeria monocytogenes causes meningoencephalitis in humans. in rodents, listeriosis is associated with granulomatous lesions in the liver and the spleen, but not with meningoencephalitis. here, infant rats were infected intracisternally to generate experimental listeric meningoencephalitis. dose-dependent effects of intracisternal inoculation with l. monocytogenes on survival and activity were noted; 10(4) l. monocytogenes organisms induced a self-limiting brain infection. bacteri ...	2001	11349080
gp96-peptide vaccination of mice against intracellular bacteria.	this work demonstrates that gp96 preparations isolated from cells infected with intracellular bacteria induce cytotoxic t-lymphocyte responses and confer protection. our findings extend previous reports on the immunogenicity of gp96-associated peptides to antigens derived from intracellular bacteria. immunization with gp96 may therefore represent a promising vaccination strategy against bacterial pathogens.	2001	11349093
[genetic mechanisms of listeria monocytogenes virulence].	current data on genetic determinants of virulence in listeria monocytogenes and on factors affecting their expression are reviewed. the role of the prfa protein, the only known transcriptional regulator that directly affects virulence gene expression and mechanisms responsible for the activity and/or concentration of this protein in the cell are considered. detailed information of outer signals modulating the level of virulence factor expression is provided. data that favor the involvement of au ...	2001	11357361
listeriolysin--a useful cytolysin.		2001	11357827
the act operon controls the level and time of c-signal production for myxococcus xanthus development.	the c-signal is a morphogen that controls the assembly of fruiting bodies and the differentiation of myxospores. production of this signal, which is encoded by the csga gene, is regulated by the act operon of four genes that are co-transcribed from the same start site. the act a and act b genes regulate the maximum level of the c-signal, which never rises above one-quarter of the maximum wild-type level of csga protein in null mutants of either gene. the act a and act b mutants have the same dev ...	2001	11359579
[hematometra & listeria monocytogenes].	the hematometra is a nosological entity that may not always be attributed to an embryonic defect of the paramesonefros; cervical-vaginal infections such as etiological possibilities due to listeria monocytogenes (lm), cervix malignant neoplasias, iatrogenias due to endometrial ablation with lasser, traumatic bloody uterine curetage and because of cervical cryocoagulation or electrocoagulation are also mentioned. the case to be reported is from a woman in reproductive stage, who is 32 years old, ...	2001	15326808
[a case of untreated systemic lupus erythematosus presenting with listerial meningitis].	a fourty-year-old woman suffered from meningitis and sepsis of listeria monocytogenes, after presenting with several early symptoms from systemic lupus erythematosus (sle). listeriosis often causes central nervous system infection with relatively high mortality rate. this infection commonly affects patients with predisposing factor, such as immunosuppression. according to the previous reports, all of the previous reports, all of listeriosis with sle received immunosuppressive therapy. to the bes ...	2001	11968742
conditioning of dendritic cells by pathogen-derived stimuli.		2001	11846223
bacterial carriers and virus-like-particles as antigen delivery devices: role of dendritic cells in antigen presentation.	replicating attenuated strains of intracellular bacteria like salmonella typhimurium, listeria monocytogenes or mycobacterium bovis bacille calmette guérin (bcg), and non-replicating virus-like-particles (vlp) consisting, for instance, of the vp1-surface component of polyoma virus offer great potential as heterologous carriers delivering foreign protein antigens for immune recognition. moreover, attenuated s. typhimurium and l. monocytogenes strains hold also great promise as delivery vehicles f ...	2001	12455402
[listeria monocytogenes induces thymocyte apoptosis in mice].	the murine thymocyte apoptosis induced by listeria monocytogenes(lm) was detected with morphology, fcm, and dna electrophoresis. the results were that lm elicited typical morphological changes of thymocyte apoptosis; the typical apoptosis peak was displayed with fcm, and typical "ladder pattern" with agarose gel electrophoresis. the apoptotic cells were found at 8 h after the mice had infected lm and reached climax at 48 h. the thymus weight significantly reduced at 16 h, and reached the lowest ...	2001	12536719
evaluation of immunotoxicity induced by single or concurrent exposure to n,n-diethyl-m-toluamide (deet), pyridostigmine bromide (pyr), and jp-8 jet fuel.	approximately 5,000 to 80,000 of the us service personnel involved in the persian gulf war have complained of a variety of nonspecific symptoms since their return in 1991. these symptoms have been collectively labeled gulf war illness and include muscle fatigue, general malaise, myalgia, impaired cognition, ataxia, headaches, fever, joint pain, skin rash, gastrointestinal disturbances, sleep disturbances, and respiratory difficulties. exposures of military and service personnel were diverse and ...	2001	12539864
involvement of listeria monocytogenes in the abortive disease.	listeria monocytogenes, an intracellular facultative germ that causes the invasion, sometimes fatal, in susceptible hosts is a food borne pathogen with ubiquitary spread that has generated a public health problem for such risk groups as: pregnant women, foetuses, new borns. 504 women with abortive disease were serologically investigated in 1999 for serotype 1a circulating in romania. the most affected age group proved to be that in the range of 20-30 yrs: 378 (75%) cases. 107 (21.23%) female pat ...	2001	12561675
occurrence of listeria spp. in captive antelope herds and their environment.	two juvenile scimitar-horned oryx (oryx dammah) at the wild animal park planckendael died from acute septicemia caused by listeria monocytogenes serovar 4b. subsequently, listeria spp. were isolated from the feces, food, and environment of seven antelope species and examined using a two-stage enrichment procedure in fraser broth, followed by isolation on palcam agar. a total of 40/170 samples (23.5%) was positive for listeria spp. no organisms were cultured in 83/170 samples (48.8%), and 47 samp ...	2001	12785709
choosing and preparing antigen-presenting cells.	the first issue in many antigen-processing experiments is to choose and obtain appropriate antigen-presenting cells (apcs). macrophages have characteristics that dictate their use in certain antigen-processing experiments, so this unit describes preparation of activated macrophages, which involves eliciting peritoneal macrophages from mice by infection with listeria monocytogenes. this method is often preferred because the resulting macrophages are more consistently activated to a high degree, b ...	2001	18432740
animal model for infection with listeria monocytogenes.	this unit describes methods for infecting mice with l. monocytogenes. optimal media for growth and methods to maintain bacterial virulence by passage through mice are included. methods for determining the severity of splenic and hepatic infection are detailed, with strategies for distinguishing innate from specific immune responses following l. monocytogenes infection. this infection induces mhc class i-restricted cd8(+) cytolytic t lymphocytes that clear infection and provide long-term immunity ...	2001	18432760
recombinant single chain antibodies in bioelectrochemical sensors.	recombinant antibodies provide an emerging strategy in the development of new immunosensors. in particular, single chain antibodies (scfvs) can be isolated and expressed in bacterial systems that also allow their in vitro manipulation at the gene level. in this work, we present for the first time results of single-chain phage displayed antibodies combined with amperometric detection and its application as an immunosensor. the scfv is immobilized on a carbon electrode and used to capture and quan ...	2001	18968440
characterization of bacteriocin n15 produced by enterococcus faecium n15 and cloning of the related genes.	enterococcus faecium n15 was isolated from nuka (japanese rice-bran paste), which is utilized as starter in the fermenting of vegetables, and was found to produce a bacteriocin that exhibited a broad spectrum of activity, including activity against listeria monocytogenes and bacillus circulans jcm2504. the bacteriocin was sensitive to proteases (alpha-chymotrypsin, proteinase k, trypsin, and pepsin) and alpha-amylase, but it was resistant to lipase. the bacteriocin was resistant to heat treatmen ...	2001	16233010
is listeria monocytogenes an important pathogen for prosthetic joints?	listeria monocytogenes usually causes meningitis or bacteremia, often in immunocompromised adults, pregnant women, or infants. we report a case of septic arthritis caused by l. monocytogenes in a patient with seronegative rheumatoid arthritis (ra) whose hip replacement was infected. she subsequently died, probably secondary to an adult respiratory distress syndrome, a rare complication of listerial infection. we also reviewed all 18 previously reported cases of septic arthritis caused by l. mono ...	2001	17039086
production of mortadella: behavior of listeria monocytogenes during processing and storage conditions.	the presence of listeria monocytogenes in ready-to-eat meat products is cause of concern to the food industry as well as to health authorities. studies were conducted to evaluate the presence of l. monocytogenes in mortadellas acquired at retail stores and to evaluate the fate of two levels of a l. monocytogenes pool spiked in two different formulations of the product, cooked under commercial conditions and stored at refrigeration (7°c) and room temperature (25°c). among the samples collected at ...	2001	22061161
occurrence of escherichia coli o157:h7, listeria monocytogenes, salmonella and campylobacter spp. on beef carcasses in northern ireland.	a survey of beef carcasses was conducted in all 10 european community approved abattoirs in northern ireland to determine the incidence of escherichia coli o157:h7. analyses were based on excised samples of neck meat taken less than 48 h post-kill. overall, 780 carcasses were sampled and all were negative for e. coli o157:h7. a sub-set of samples was analysed for the presence of listeria monocytogenes (n=200), salmonella (n=200) and campylobacter spp.(n=100). l. monocytogenes was not detected bu ...	2001	22062423
antagonistic effect on listeria monocytogenes and l. innocua of a bacteriocin-like metabolite produced by lactic acid bacteria isolated from sucuk.	two lactobacilli and four pediococci strains producing bacteriocin-like metabolities isolated from sucuk were tested with agar spot tests and well diffusion assays for their inhibitory activity against 16 listeria strains, also isolated from sucuk. the production of organic acids and hydrogen peroxide limited, l. sake lb 706 (used as a bacteriocin producer strain) and the isolated lactic acid bacteria (lab) showed inhibitory activity against all of the listeria strains, while l. sake lb 706-a (u ...	2001	22062969
a promoter probe plasmid based on green fluorescent protein : a strategy for studying meningococcal gene expression.	many bacterial genes are regulated in an environment-responsive fashion, and from the perspective of a pathogen, the host represents just another environment. many genes that contribute to virulence are differentially expressed in response to host environments that they encounter during colonization and invasion (1). recognition of this has led to the development of selection or reporter systems that utilize the increased activity of promoters during growth in vivo to identify genes that are sel ...	2001	21337172
plasmid-mediated streptomycin resistance of listeria monocytogenes.	a strain of streptomycin-resistant listeria monocytogenes lm35 isolated from imported frozen beef was examined in this study. in conjugation studies, the l. monocytogenes lm35 strain harbouring two plasmids of 54, 3.0, 2.8 and 2.7 kilobase was used as the donor and streptomycin-sensitive and plasmidless l. monocytogenes lm65 and lm100 strains as the recipients. streptomycin resistance was transferred to l. monocytogenes lm65 and lm100 strains at frequencies of 3.3 × 10(-8) and 1.2 × 10(-9) per i ...	2001	22973158
production of bacteriocin-like metabolites by lactic acid cultures isolated from sucuk samples.	a total of 51 sucuk samples, obtained from different regions of turkey, were examined for lactic acid bacteria (lab) strains producing putative bacteriocin-like metabolites. for detection of antagonistic activity, agar spot and well diffusion assay tests were used. lactobacillus sake lb790, listeria monocytogenes li6, staphylococcus aureus st44 and escherichia coli nrrl b-3704 were used as indicator organisms. strains having antimicrobial activity were also tested against clostridium perfringens ...	2000	22060908
effect of nisin and its combination with sodium chloride on the survival of listeria monocytogenes added to raw buffalo meat mince.	antilisterial activity of nisin (nisaplin), alone at concentrations of 400 and 800 iu/g and in combination with 2% sodium chloride was incorporated in raw buffalo meat mince. samples of the raw meat mince were inoculated with 10(3) colony forming units (cfu)/g of l. monocytogenes and stored at 4°c for 16 days and at 37°c for 36 h. initial estimates of ph, extract release volume, mesophilic and psychrophilic counts were found to be 5.74, 48 ml, 3.5×10(5) and 1.0×10(5) cfu/g of meat, respectively. ...	2000	22062071
microbiological contamination of raw beef trimmings and ground beef.	to survey the microbiological quality of beef trimmings and final-ground beef, samples were collected from eight commercial grinding facilities, including trimmings from fed-cattle, culled-beef cows, culled-dairy cows, imported-beef trimmings and finished-ground products. trim samples (core and purge) and ground product samples (n=586) were evaluated for aerobic plate (apc), total coliform (tcc), escherichia coli (ecc) and staphylococcus aureus counts and the presence of salmonella spp. and list ...	2000	22061902
effects of chemical hurdles on microbiological and oxidative stability of a cooked cured emulsion type meat product.	two combinations of hurdles, 2.0% lactate+0.5% acetate or 2.0% lactate+0.25 % glucono-delta-lactone (gdl), were both found to prevent growth of listeria monocytogenes inoculated onto sliced saveloys manufactured with 60 or 150 ppm nitrite. the saveloys were packed in modified atmosphere (80% n(2)/20% co(2)) using a film with low oxygen transmission rate (0.45 cm(3)/m(2)/atm/24 h) and stored at 5 or 10°c for up to 4 weeks. changes in red colour (measured as minolta a-values) and lipid oxidation [ ...	2000	22061582
utilization of microbes to process and preserve meat.	this paper discusses how, and to what extent, the addition of microorganisms to meats helps to meet the needs of consumers and industry. lactic acid bacteria adapted to meats improve the safety of fermented sausages by means of acid formation. using selected strains, the safety of certain non-fermented, perishable meat products may be improved without affecting their shelf life. certain bacteriocin-forming cultures may reduce the levels of listeria monocytogenes in some meat products significant ...	2000	22061897
[current epidemiological and clinical features meningitis in a northern italian area]	objectives: to study etiological, epidemiological and clinical features of 97 cases of acute meningitis. methods: ninety-seven cases of acute meningitis were examined in adult hiv-negative patients admitted to the infectious diseases unit of the azienda ospedale-universita s. anna in ferrara. demographic, etiological, epidemiological and clinical data were analyzed. results: all cases were divided into two groups according to the macroscopic aspect of cerebrospinal fluid (csf): purulent csf (50 ...	2000	12711895
immunohistochemical study of constitutive neuronal and inducible nitric oxide synthase in the central nervous system of goat with natural listeriosis.	the expression of both constitutive and inducible forms of nitric oxide synthase (nos) was investigated by immunohistochemical staining of formalin-fixed paraffin-embedded sections in normal and listeria monocytogenes-infected brains of goats. in normal control goats, a small number of neurons showed immunoreactivity of both inos and nnos, and the number of inos-positive neurons was higher than the number of nnos-positive neurons. in natural listeriosis, listeria antigens were easily immunostain ...	2000	14614301
effect of silica inhalation on the pulmonary clearance of a bacterial pathogen in fischer 344 rats.	silica inhalation predisposes workers to bacterial infection and impairments in pulmonary defense function. in this study, we evaluated the effect of pre-exposure to silica on lung defense mechanisms by use of a rat pulmonary listeria monocytogenes infection model. male fischer 344 rats were exposed by inhalation to filtered air or silica (15 mg/m3 x 6 h/day x 5 days/wk). after 21 or 59 days of silica exposure, the rats were inoculated intratracheally with 5 x 10(3) l. monocytogenes. at 0 (nonin ...	2000	11361057
nosocomial listeria gastroenteritis in a newborn, confirmed by random amplification of polymorphic dna.		2000	11284931
secrets of actin-based motility revealed by a bacterial pathogen.	actin-based cell motility is a complex process involving a dynamic, self-organizing cellular system. experimental problems initially limited our understanding of this type of motility, but the use of a model system derived from a bacterial pathogen has led to a breakthrough. now, all the molecular components necessary for dynamic actin self-organization and motility have been identified, setting the stage for future mechanistic studies.	2000	11253363
[clinical and laboratory diagnosis of listeria monocytogenes on the basis of own investigations].	the authors have described the issues surrounding listeria monocytogenes infection with reference to cases diagnosed and managed during the 5-year period (1995-2000) in the clinical department of neonatal pathology and intensive care of the national institute of mother and child in warsaw. four cases of congenital listeriosis have been diagnosed. some mothers presented with "flu-like" symptoms. all mothers delivered prematurely (29 hbd - 32 hbd). among the 4 infants the most common clinical feat ...	2000	11328973
use of the molecular typing methods to evaluate the control of listeria monocytogenes contamination in a raw milk and dairy products.	nineteen serogroup 1/2a listeria monocytogenes strains isolated from raw milk, dairy products and salt water in one dairy were analyzed. pulsed field gel electrophoresis (pfge) and ribotyping were used to determine whether these strains isolated over a 8-month period are epidemiologically related. the samples of raw milk were contaminated by different l. monocytogenes clones. the clones isolated from dairy products (with the exception of one sample) and salt water were identical. comparative gen ...	2000	11271825
post-transplant epididymitis and orchitis following listeria monocytogenes septicaemia.	we report the occurrence of epididymitis and orchitis 1 week after the onset of listeriosis in an 11-month-old boy receiving an orthotopic liver transplantation for biliary atresia. immunologic implications of listeria monocytogenes-induced testicular inflammation are discussed, and the potential role of immunosuppression with tacrolimus is also discussed.	2000	11272610
[urinary retention as the first sign of rhombencephalitis due to listeria monocytogenes].		2000	11244698
laxp180, a mammalian acta-binding protein, identified with the yeast two-hybrid system, co-localizes with intracellular listeria monocytogenes.	the listeria monocytogenes surface protein acta is an important virulence factor required for listerial intracellular movement by inducing actin polymerization. the only host cell protein known that directly interacts with acta is the phosphoprotein vasp, which binds to the central proline-rich repeat region of acta. to identify additional acta-binding proteins, we applied the yeast two-hybrid system to search for mouse proteins that interact with acta. a mouse cdna library was screened for acta ...	2000	11207567
a novel function of inib from listeria monocytogenes: activation of nf-kappab in j774 macrophages.	listeria monocytogenes causes a pro-inflammatory response on adhesion to macrophages. upregulation of inflammation genes involves the transcription factor nf-kappab. several components of l. monocytogenes, including lipoteichoic acid (lta), phospholipases and listeriolysin o (llo), have since been shown to mediate nf-kappab activation. here, we report that purified recombinant inlb, but not internalin (inla), is a potent activator of nf-kappab in the mouse macrophage-like cell line j774. express ...	2000	11207569
the invasion protein inib from listeria monocytogenes activates plc-gamma1 downstream from pi 3-kinase.	entry of the bacterial pathogen listeria monocytogenes into non-phagocytic mammalian cells is mainly mediated by the inlb protein. here we show that in the human epithelial cell line hep-2, the invasion protein inlb activates sequentially a p85beta-p110 class i(a) pi 3-kinase and the phospholipase c-gamma1 (plc-gamma1) without detectable tyrosine phosphorylation of plc-gamma1. purified inlb stimulates association of plc-gamma1 with one or more tyrosine-phosphorylated proteins, followed by a tran ...	2000	11207601
listeriolysin o-induced stimulation of mucin exocytosis in polarized intestinal mucin-secreting cells: evidence for toxin recognition of membrane-associated lipids and subsequent toxin internalization through caveolae.	lysteriolysin o (llo) induces a microtubule-dependent activation of mucin exocytosis in the human mucin-secreting ht29-mtx. cholesterol inhibits the llo-induced mucin exocytosis, whereas the oxidized form of cholesterol had no inhibitory effect. llo-induced mucin exocytosis inhibited by cholesterol can be restored by enzymatic treatment with cholesterol oxidase. inhibition of cholesterol synthesis in ht29-mtx cells results in a decrease in the llo-induced mucin exocytosis. other lipids such as g ...	2000	11207603
[effect of cultivation temperature on nucleic acid level in bacteria listeria monocytogenes and yersinia pseudotuberculosis].	the relationship between the multiplication of bacteria, the content of nucleic acid and the specific rate of their growth during their batch cultivation in nutrient broth and mineral medium at temperatures of 37 degrees c and 4-6 degrees c was studied in the causative agents of saprozoonotic infections with l. monocytogenes and y. pseudotuberculosis used as typical representatives of such bacteria. the content of dna was shown to remain practically unchanged after the alteration of cultivation ...	2000	11210627
plasma cytokine response in mice with bacterial infection.	exposure to microorganisms elicts the production of cytokines. these soluble factors enhance several innate immune functions and regulate the ensuing specific immune response aimed at limiting the spread of infection.	2000	11200363
characterization by molecular cloning and sequencing of the gene encoding an aminopeptidase from listeria monocytogenes.	the pepc gene of listeria monocytogenes encodes aminopeptidase c that is predicted to share 72% amino acid sequence similarity and 53% sequence identity with the cysteine aminopeptidase pepc from lactococcus lactis. the gene product also shows strong similarity to aminopeptidase c from streptococcus thermophilus and lactobacillus helveticus, and to a cysteine proteinase/bleomycin hydrolase from saccharomyces cerevisiae. the enzyme from l. monocytogenes displayed broad n-terminal hydrolytic activ ...	2000	11204766
[infectious and metabolic nervous system complications of systemic cancer].	to review the incidence and causes of the infections and metabolic diseases of the nervous system in patients with systemic neoplasias.	2000	11205570
neonatal listeriosis in algeria: the first two cases.		2000	11168082
liver abscess due to listeria monocytogenes.		2000	11168114
[quantitative risk assessment related to microbial food contamination].	the four keystones of quantitative risk assessment are hazard identification, exposure assessment, dose-response assessment and risk characterization. this paper considers the different steps of risk assessment and their application to food microbiology. traditionally, quantitative risk assessment has been viewed simply as a method to estimate risk. however, when we conduct a complete risk assessment including different factors from "farm to fork" it can serve to understand the risk process. qua ...	2000	11183481
microbiology. listeria enlists host in its attack.		2000	11184728
multistate outbreak of listeriosis--united states, 2000.	since may 2000, 29 illnesses caused by a strain of listeria monocytogenes (lm) have been identified in 10 states: new york (15 cases); georgia (three); connecticut, ohio, and michigan (two each); and california, pennsylvania, tennessee, utah, and wisconsin (one each). dates of lm isolation ranged from may 17 through november 26 with 26 (90%) infections occurring since july 15. when subtyped, the lm isolates from these cases were indistinguishable by pulsed-field gel electrophoresis (pulsenet pat ...	2000	11190115
control of foodborne pathogens during sufu fermentation and aging.	control of the foodborne pathogens escherichia coli o157:h7, salmonella typhimurium, staphylococcus aureus, and listeria monocytogenes during sufu fermentation was evaluated. before fermentation, pathogens were inoculated onto tofu (substrate for sufu) at 5 log cfu/g or 3 log cfu/g, and starter culture (actinomucor elegans) was inoculated at 3 log cfu/g. after 2 days of fermentation at 30 degrees c, the four pathogens reached 7 to 9 log cfu/g, and the mold count reached 6 to 7 log cfu/g. after f ...	2000	11192025
[use of poly-beta-oxybutyric acid by yersinia pseudotuberculosis and listeria monocytegenes bacteria at various temperatures].	a comparative investigation of the intracellular content of poly-beta-hydroxybutyric acid showed that yersinia pseudotuberculosis strains accumulated, on the average, lower amounts of this reserve substance than listeria monocytogenes strains. the intracellular pool of poly-beta-hydroxybutyric acid was responsible for the growth of the bacteria at low temperatures (4-6 degrees c) in the absence of any exogenous carbon and energy source.	2000	11195574
lessons from an outbreak of listeriosis related to vacuum-packed gravad and cold-smoked fish.	the first lesson learned from this outbreak was that vacuum-packed rainbow trout is not only an excellent medium for the growth of listeria monocytogenes, but may also cause human listeriosis. another lesson is that one single fish processing plant may spread multiple clonal types of l. monocytogenes by selling contaminated products to consumers. thus, when investigating fish-borne outbreaks of listeriosis one should identify and type several isolates of l. monocytogenes from each food and envir ...	2000	11156259
listeria in tropical fish and fishery products.	listeria monocytogenes is considered to be a ubiquitous organism occurring in both terrestrial and aquatic habitats. this organism has been isolated from fish and fishery products from different parts of the world and interestingly the incidence rate reported from tropical fish is rather low. varying methodologies have been used by different investigators to study the incidence of l. monocytogenes in fish. data on virulence of seafood-associated strains are lacking. for quality assurance in the ...	2000	11156260
listeria monocytogenes in the smoked salmon industry.	smoked salmon is sporadically contaminated with listerial monocytogenes. contamination levels are normally low and consumers are probably seldom exposed to risk concentrations. no clones of l. monocytogenes seem to be specific to smoked salmon, some clones found in smoked salmon having been isolated from several sources, including patients. cold-smoking has been shown to eliminate l. monocytogenes in challenge tests at temperatures from 17.1 to 21.1 degrees c, while from 22.2 to 30 degrees c the ...	2000	11156261
epidemiology of human listeriosis and seafoods.	while rarely diagnosed prior to 1960, more than 10,000 cases of listeriosis were recorded in the medical literature between 1960 and 1982, and thousands more have been reported annually world-wide [rocourt j., 1991. human listeriosis, 1989. who/hpp/fos/91.3, world health organization, geneva, switzerland; rocourt, j., brosch, r., 1992. human listeriosis, 1990. who/hpp/fos/92.3, world health organization, geneva, switzerland; rocourt, j., jacquet, ch., bille, j., 1997. human listeriosis, 1991/199 ...	2000	11156263
potential of listeria hazard in african fishery products and possible control measures.	africa contributes 5.54 million mt (4.5%) to the world harvest of aquatic organisms. fisheries represent a vital sector for many countries in africa, both for domestic food supply, employment opportunities and foreign exchange earnings. despite the low level of african fish production and export in comparison with the other continents, fish represent the major protein source in many countries (36-58% of animal proteins in c te d'ivoire, congo, senegal, angola) and fishing is a vital activity for ...	2000	11156264
microbiological criteria for listeria monocytogenes in foods under special consideration of risk assessment approaches.	this paper shortly summarizes data related to risk assessment of listeria monocytogenes. from available data on risk assessment, it is concluded that the levels of l. monocytogenes consumed is an important factor affecting the incidence of listeriosis. foods that do not support the growth of l. monocytogenes are unlikely to be a source of listeriosis, whereas foods that support the growth to high levels, should be the target of risk management efforts. based on current epidemiological informatio ...	2000	11156265
risk assessment of listeria monocytogenes in fish products: some general principles, mechanism of infection and the use of performance standards to control human exposure.	risk assessment is increasingly used as a scientific process to assess the potential for adverse health effects to occur and as a basis for management of unacceptable risks. for each risk assessment activity, the purpose of the assessment should be clearly stated. for listeria monocytogenes, the purpose of risk assessment may be providing information on the relative contribution of listeriosis to infectious diseases. for control purposes, the emphasis may be put on factors contributing to the ri ...	2000	11156266
predictive modelling of the growth and survival of listeria in fishery products.	predictive microbiology provides a powerful tool to aid the exposure assessment phase of 'quantitative microbial risk assessment'. using predictive models changes in microbial populations on foods between the point of production/harvest and the point of eating can be estimated from changes in product parameters (temperature, storage atmosphere, ph, salt/water activity, etc.). thus, it is possible to infer exposure to listeria monocytogenes at the time of consumption from the initial microbiologi ...	2000	11156267
present situation in canada regarding listeria monocytogenes and ready-to-eat seafood products.	the present situation regarding listeria monocytogenes and ready-to-eat (rte) seafood is discussed. an updated regulatory policy on l. monocytogenes directs inspection and compliance action to those rte foods capable of supporting growth of the organism and is based on a combination of inspection, environmental sampling and product testing. the incidence of l. monocytogenes in imported seafood products in 1996-1997 and 1997-1998 was 0.88 and 0.3%, respectively. with respect to domestic products, ...	2000	11156268
risk assessment used to evaluate the us position on listeria monocytogenes in seafood.	human listeriosis has been associated with consumption of food including seafood. surveillance information on the presence of listeria monocytogenes in seafood products is presented as a background for steps that are being taken to inform risk managers of risks associated with particular food products. united states policy for l. monocytogenes in food has been shaped by our increasing knowledge of the epidemiology of outbreaks and sporadic cases of human listeriosis, the potentially severe publi ...	2000	11156269
control options for listeria monocytogenes in seafoods.	at least three outbreaks of listeriosis associated with seafood have been reported. listeria monocytogenes is widely distributed in the general environment including fresh water, coastal water and live fish from these areas. contamination or recontamination of seafood may also take place during processing and low levels (< 100 cfu/g) of l. monocytogenes are frequently found on seafood including ready-to-eat (rte) products. apart from heat treatment, which is very effective, there are few options ...	2000	11156271
secretion of different listeriolysin cognates by recombinant attenuated salmonella typhimurium: superior efficacy of haemolytic over non-haemolytic constructs after oral vaccination.	viable antigen (ag) delivery systems expressing defined pathogen-derived proteins represent powerful candidates for future vaccination strategies. here, recombinant (r)salmonella typhimurium aroa strains secreting listeriolysin (hly) of listeria monocytogenes in haemolytic or non-haemolytic form were constructed to direct these carriers into cytosolic or phagosomal host cell compartments, respectively. oral and intravenous (i.v.) vaccination of mice with either construct induced 'transporter ass ...	2000	11165923
in vitro activities of 22 antimicrobial agents against listeria monocytogenes strains isolated in barcelona, spain. the collaborative study group of listeriosis of barcelona.	the in vitro activity of 22 antimicrobial agents against 82 human listeria monocytogenes strains isolated in barcelona from 1994 to 1998 was determined. ampicillin and gentamicin showed good in vitro activity against all strains (mic90: 1 and < or = 0.25 microg/ml, respectively). no resistance to rifampin or co-trimoxazole was detected and only one strain was resistant to tetracycline. of the nine fluoroquinolones tested, clinafloxacin and gemifloxacin were the most active compounds (mic90: 0.12 ...	2000	11146253
acute bacterial meningitis in adults. a 12-year review.	one hundred three episodes of acute bacterial meningitis in adults hospitalized in edmonton's 2 largest hospitals from 1985 to 1996 were reviewed. cases complicating neurosurgery were excluded. most cases were community-acquired (87%). twenty-three cases remained culture-negative, and there was no statistical relation between culture negativity and antibiotic pretreatment. streptococcus pneumoniae was the predominant pathogen (52.5%), but listeria monocytogenes was the second most common isolate ...	2000	11144034
behaviour of listeria monocytogenes and autochthonous flora on meat stored under aerobic, vacuum and modified atmosphere packaging conditions with or without the presence of oregano essential oil at 5 degrees c.	the effect of aerobic, modified atmosphere packaging (map; 40% co2/30% o2/30% n2) and vacuum packaging (vp) on the growth/survival of listeria monocytogenes on sterile and naturally contaminated beef meat fillets was studied in relation to film permeability and oregano essential oil. the dominant micro-organism(s) and the effect of the endogenous flora on the growth/survival of l. monocytogenes were dependent on the type of packaging film. the fact that l. monocytogenes increased whenever pseudo ...	2000	11123463
effect of various environmental parameters on the recovery of sublethally salt-damaged and acid-damaged listeria monocytogenes.	the influence of supplementing the culture medium with magnesium sulphate, d-glucose, l-cysteine, catalase or lithium chloride, of incubation temperature and of oxygen availability on the recovery of salt- or acid-damaged listeria monocytogenes, was studied on a solid repair medium according to a hadamard matrix, with seven parameters varying between a high and a low level. the most important factors for repair of stressed listeria were further studied with complete factorial design experiments. ...	2000	11123467
isolation of a bacteriocin-producing lactococcus lactis subsp. lactis and application to control listeria monocytogenes in moroccan jben.	use of a bacteriocin-producing lactococcal strain to control listeria monocytogenes in jben.	2000	11123469
reduction of normal flora by irradiation and its effect on the ability of listeria monocytogenes to multiply on ground turkey stored at 7 degrees c when packaged under a modified atmosphere.	listeria monocytogenes did not multiply faster during storage at 7 degrees c on irradiated than on nonirradiated raw ground turkey, and there was a concentration-dependent inhibition of its multiplication by co2. ground turkey was gamma irradiated at 5 degrees c to 0, 1.5, and 2.5 kgy and inoculated (approximately 100 cfu/g) after irradiation with a cocktail of l. monocytogenes atcc 7644, 15313, 49594, and 43256. the meat was then packaged in air-permeable pouches or under atmospheres containing ...	2000	11131894
evaluation of batch and semicontinuous application of high hydrostatic pressure on foodborne pathogens in salsa.	the effects of high hydrostatic pressure (hpp; 545 mpa) on strains of escherichia coli o157:h7, listeria monocytogenes, enterotoxigenic staphylococcus aureus, and nonpathogenic microorganisms were studied in tomato-based salsa. products were evaluated for the survival of the inoculated pathogens following hpp treatment and after storage at 4 degrees c and 21 to 23 degrees c for up to 2 months. inoculated samples without hpp treatment, stored under the same conditions, were also evaluated to dete ...	2000	11131896
hijacking of apoptotic pathwaysby bacterial pathogens.	increasing evidence indicates that apoptosis of the host cell may constitute a defense mechanism to confine the infection by bacterial pathogens. certain pathogens have developed elegant mechanisms to modulate the fate of the host cell, which include induction or blockage of apoptosis. these studies will promote our understanding of the pathogenesis of infectious diseases and aid the development of means for therapeutic intervention.	2000	11137044
comparative evaluation of adhesion and biofilm formation of different listeria monocytogenes strains.	thirteen listeria monocytogenes strains were used to grow biofilms on glass surfaces in static conditions at 37 degrees c for up to 4 days. after the initial 3-h adhesion and in subsequent 1-day intervals, cell numbers were determined using standard plate count after swabbing the cells from the glass surface. the three-dimensional structure of in situ biofilms was determined by confocal scanning laser microscopy (cslm). after 3 h incubation, bacterial cells for all 13 strains of l. monocytogenes ...	2000	11139010
behaviour of listeria monocytogenes during the manufacture and ripening of manchego and chihuahua mexican cheeses.	the ability of listeria monocytogenes to survive the mexican manchego and chihuahua cheese-making processes and its persistence during the ripening stages of both cheeses was examined. commercial pasteurized and homogenized whole milk was inoculated with listeria monocytogenes (strain atcc 19114) to a level between 2 x 10(6) and 9 x 10(6) cfu/ml. the milk was used to make mexican manchego and chihuahua cheeses in a 25-l vat. mexican manchego cheese was ripened for 5 days and chihuahua cheese for ...	2000	11139015
pulsed-field gel electrophoresis (pfge) typing of listeria strains isolated from a meat processing plant over a 2-year period.	as part of a hygiene monitoring program in a meat processing plant a total of 131 listeria isolates were detected by sampling different processing areas and meat products within a 2-year period. the isolates were differentiated by means of phenotypic characteristics. furthermore, the genomic apai and smai fragment patterns of all isolates were examined by pulsed-field gel electrophoresis (pfge). pfge using smai and apai yielded 15 (listeria monocytogenes), 20 (listeria innocua) and six (listeria ...	2000	11139016
incidence of listeria spp. and salmonella spp. in horsemeat for human consumption.	the incidence of salmonella spp., listeria spp. and listeria monocytogenes in horsemeat for human consumption was investigated. one-hundred and twenty-one samples of frozen horsemeat collected from two brazilian abattoirs were analysed over a period of 1 year. twenty-two samples (18.2%) were positive for listeria spp. with nine (7.4%) containing l. monocytogenes. none of the samples harbored salmonella spp.	2000	11139017
low-dose irradiation as a measure to improve microbial quality of ice cream.	the present study was undertaken to investigate the efficacy of low-dose irradiation to improve the microbial safety of ice cream. initially three different flavors (vanilla, strawberry and chocolate) of ice cream were exposed, at -72 degrees c, to doses of 1, 2, 5, 10 and 30 kgy to gamma-radiation. irradiation at 1 kgy resulted in reduction of microbial population by one log cycle, thus meeting the requirement limits prescribed by bureau of indian standards. pathogens such as listeria monocytog ...	2000	11139019
occurrence of and a possible mechanism for resistance to a quaternary ammonium compound in listeria monocytogenes.	in a study of 200 listeria monocytogenes isolates, 10% were determined to be resistant to benzalkonium chloride (bc). serial subcultivation of initially bc sensitive (bc(s)) and bc resistant (bc(r)) isolates in sublethal concentrations of bc resulted in enhanced and approximately equal resistance of all strains to the compound. fifty per cent of the bc(r) isolates showed resistance to ethidium bromide (eb) as well. a proton motive force (pmf)-dependent efflux of eb was demonstrated in bc(r) isol ...	2000	11139022
nisin-curvaticin 13 combinations for avoiding the regrowth of bacteriocin resistant cells of listeria monocytogenes atcc 15313.	nisin (25-100 iu/ml) and curvaticin 13 (160 au/ml), a bacteriocin produced by lactobacillus curvatus sb13, were shown to have a bactericidal effect against listeria monocytogenes atcc 15313 in tsb-ye broth (ph 6.5), but it was only transitory. regrowth was not due to the loss of bacteriocin activity. cells surviving nisin or curvaticin 13 were more resistant to the respective bacteriocin than the parental strain. survivors to curvaticin 13 were resistant to the class iia bacteriocins (camocin cp ...	2000	11139023
[isolation of listeria spp., aeromonas spp., and vibrio spp. from seafood products].	forty-one strains of listeria, aeromonas and vibrio have been isolated in 71 samples of seafood, both raw and ready to eat and frozen. l. monocytogenes, detected by pcr also, is found in the smoked salmon only. aeromonas spp. and vibrio spp. are isolated in the raw products (shrimps and shellfish). no relationship is found between the presence of such microrganisms and the common indicator bacteria. finally, the health hazard related to strong contamination and the need to diversify the food saf ...	2000	11140096
modulation of acta gene expression in listeria monocytogenes by iron.	this study analysed the invasiveness of listeria monocytogenes into enterocyte-like caco-2 cells in which iron depletion was achieved by picolinic acid treatment. both entry and intracellular multiplication varied depending on the endogenous iron content of bacterial and eukaryotic cells. the behaviour within enterocytes was correlated with a 10-fold increased transcription of the acta gene observed in bacterial cells grown under conditions of iron stress.	2000	10933250
in vivo cytokine production and resistance to infection after acute exposure to 3,4-dichloropropionaniline.	3,4-dichloropropionaniline (propanil) is an extensively used postemergent herbicide that has been shown to produce toxic and immunotoxic effects. the present report examined if acute exposure to propanil altered in vitro or in vivo cytokine production in response to antigenic stimulation. studies to determine resistance to infection by the intracellular bacterium listeria monocytogenes after exposure to propanil were also conducted. our experiments demonstrate that in vivo exposure to propanil d ...	2000	10933756
in vivo and in vitro assessment of the virulence of listeria monocytogenes strains.	to evaluate whether the in vitro model (invasion and intracellular growth in caco-2 cells) for determining virulence is a suitable alternative to the in vivo model (50% lethal dose), we compared the levels of virulence obtained with the two models. we tested l. monocytogenes strains isolated from food and clinical samples during three episodes of listeriosis occurring in italy in the period 1993-1995. we also tested l. monocytogenes strains isolated from food during official control activities. ...	2000	10939044
quantitative risk assessment for listeria monocytogenes in smoked or gravad salmon and rainbow trout in sweden.	the objective of the present work was to develop a quantitative risk assessment model in which the exposure and risk of acquiring listeriosis from consumption of packaged smoked or gravad salmon and rainbow trout were estimated. an excel spreadsheet model was constructed in which variables were represented by distributions based on surveys of l. monocytogenes in these food products, and on demographic and consumption data. growth or inactivation was not included in the model. the model was run t ...	2000	10939268
comparison of microbiological risk assessment studies published.	the fao/who risk analysis framework and principles are in the process of being implemented in different national and international settings. the importance of a further development of international co-operation based upon agreed principles in this area is stressed in the codex alimentarius system, as well as under the wto/sps agreements. key input in this context will come from the presentation of formalised microbiological risk assessments. the number of peer-review published microbiological ri ...	2000	10939269
mycobacterium tuberculosis h37rv comparative gene-expression analysis in synthetic medium and human macrophage.	mycobacteria are intracellular pathogens that survive and grow in host macrophages. following phagocytosis, sustained intracellular bacterial growth depends on its ability to avoid destruction by macrophage-mediated host defences such as lysosomal enzymes, reactive oxygen and the reactive nitrogen intermediates. this suggests that the interaction between host cell and microbe is delicately balanced, and can be tipped in favour of either organism. the identification of mycobacterium tuberculosis ...	2000	10940566
dithiothreitol enhances listeria monocytogenes mediated cell cytotoxicity.	the hybridoma ped-2e9 based cytotoxicity assay was developed to distinguish virulent from avirulent listeria species in 6 hr. the cytotoxicity effect on ped-2e9 was reported to be primarily due the cytolytic action of listeriolysin o (llo), produced by l. monocytogenes. in this study, the effect of a reducing agent, dithiothreitol (dtt, 0-2 mm) that is known to activate llo was investigated to make the ped-2e9 based cytotoxicity assay an even more sensitive and rapid. also, we examined the effec ...	2000	10941925
e. coli invasion of brain microvascular endothelial cells as a pathogenetic basis of meningitis.	a major limitation to advances in prevention and therapy of bacterial meningitis is our incomplete understanding of the pathogenesis of this disease. successful isolation and cultivation of bmec, which constitute the blood brain barrier, and the development of experimental hematogenous meningitis animal model, which mimics closely the pathogenesis of human meningitis, enabled us to dissect the pathogenetic mechanisms of bacterial meningitis. we have shown for the first time using e. coli as a pa ...	2000	10804851
internalization of listeria monocytogenes by nonprofessional and professional phagocytes.		2000	10804864
cd8+ t-cell-mediated response to listeria monocytogenes taken up in the liver and replicating within hepatocytes.	like most other organisms that enter the bloodstream, the bulk of listeria monocytogenes injected i.v. into mice is taken up by the liver. listeriae not killed rapidly by infiltrating neutrophils are internalized by hepatocytes which constitute the principal site of intracellular replication in the liver. cd8+ t cells play a critical role in eliminating infected hepatocytes and resolving listerial infections of the liver; the specific mechanisms involved are not understood fully. here, we review ...	2000	10807511
innate defenses in the liver during listeria infection.	the majority of pathogens entering the bloodstream are cleared by the liver. listeria monocytogenes, an important natural pathogen of humans, is a useful tool for examining protective immune responses during systemic infections of mice. innate immunity contributes to blood clearance and eventual sterilization of the liver subsequent to listeria infections. effector mechanisms expressed in the liver early after infections are orchestrated by complex interactions between resident populations, i.e. ...	2000	10807514
[the multiplication dynamics of pathogenic bacteria in relation to the trophic and temperature cultivation conditions].	the comparative study of the dynamics of multiplication of listeria monocytogenes and yersinia pseudotuberculosis in organic and synthetic media and in distilled water at temperatures of 37 degrees c and 6 degrees c was carried out. this study revealed that in organic media the multiplication of bacteria was good at 37 degrees c and 6 degrees c. in mineral media and distilled water their multiplication was observed only at 6 degrees c. moreover, conditions necessary for the multiplication of pat ...	2000	10808565