Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| the mycobacterium tuberculosis phagosome in human macrophages is isolated from the host cell cytoplasm. | knowledge of whether mycobacterium tuberculosis resides within a relatively impermeable membrane-bound vacuole or is free within the cytoplasm within its host cell is central to an understanding of the immunobiology of this intracellular parasite but is a matter of controversy. to explore this issue, we assessed the accessibility of medium-size protein molecules (fab fragments of 50,000 da) to m. tuberculosis within human macrophages. we infected the macrophages with wild-type or green fluoresce ... | 2002 | 12228310 |
| an rna thermosensor controls expression of virulence genes in listeria monocytogenes. | in listeria monocytogenes, virulence genes are maximally expressed at 37 degrees c, almost silent at 30 degrees c and controlled by prfa, a transcriptional activator whose expression is thermoregulated. here, we show that the untranslated mrna (utr) preceding prfa, forms a secondary structure, which masks the ribosome binding region. mutations predicted to destabilize this structure led to virulence gene expression and invasion of mammalian cells at 30 degrees c. chemical probing, native gel ele ... | 2002 | 12230973 |
| irradiation temperature influences product quality factors of frozen vegetables and radiation sensitivity of inoculated listeria monocytogenes. | four frozen vegetables (broccoli, corn, lima beans, and peas) were gamma irradiated at subfreezing temperatures ranging from -5 to -20 degrees c to determine (i) the radiation sensitivity of an inoculated outbreak strain of listeria monocytogenes (atcc 49594), (ii) the effect of changing irradiation conditions (i.e., temperature) on that sensitivity, and (iii) the effect of the recommended radiation dose on the texture and color of irradiated frozen vegetables. the amounts of radiation necessary ... | 2002 | 12233849 |
| control of listeria monocytogenes on turkey frankfurters by generally-recognized-as-safe preservatives. | generally-recognized-as-safe chemicals applied to the surfaces of turkey frankfurters were evaluated for their ability to reduce populations of or inhibit the growth of listeria monocytogenes. frankfurters were treated prior to inoculation by dipping for 1 min in a solution of one of four preservatives (sodium benzoate, sodium propionate, potassium sorbate, and sodium diacetate) at three different concentrations (15, 20, and 25% [wt/vol]), with < 0.3% of the preservative being present for each f ... | 2002 | 12233850 |
| detection of listeria monocytogenes in pigs and pork. | in this study, we surveyed hogs (n = 300) as well as pork products (ground pork and raw chitterlings) for listeria monocytogenes. pig specimens collected before (tonsil swabs) and after slaughter (tonsils, lymph nodes, carcass swabs, and rectal contents) were examined for l. monocytogenes by enrichment with conventional enrichment broths followed by subculturing to selective agar. a multiplex polymerase chain reaction assay targeting the highly conserved 16s rrna gene of the listeria species as ... | 2002 | 12233860 |
| ascopyrone p, a novel antibacterial derived from fungi. | to assess the antimicrobial efficacy of ascopyrone p (app), a secondary metabolite formed by the fungi anthracobia melaloma, plicaria anthracina, plic. leiocarpa and peziza petersi belonging to the order pezizales. | 2002 | 12234354 |
| critical roles of myeloid differentiation factor 88-dependent proinflammatory cytokine release in early phase clearance of listeria monocytogenes in mice. | listeria monocytogenes (lm), a facultative intracellular gram-positive bacterium, often causes lethal infection of the host. in this study we investigated the molecular mechanism underlying lm eradication in the early phase of infection. upon infection with lm, both il-12 and il-18 were produced, and then they synergistically induced ifn-gamma production, leading to normal lm clearance in the host. ifn-gamma knockout (ko) mice were highly susceptible to lm infection. il-12/il-18 double knockout ... | 2002 | 12244183 |
| myd88-dependent but toll-like receptor 2-independent innate immunity to listeria: no role for either in macrophage listericidal activity. | we have assessed the requirements for toll-like receptor (tlr) signaling in vivo during early infection with listeria monocytogenes. mice deficient for tlr2, a receptor required for the recognition of gram-positive peptidoglycan, showed equivalent listeria resistance to wild-type mice. however, mice deficient for myd88, an adaptor molecule used by all tlrs, showed profound susceptibility with 3-4 logs greater listeria burden and severe spleen and liver pathology at day 3 postinfection. listeria- ... | 2002 | 12244184 |
| development of gfp vectors for expression in listeria monocytogenes and other low g+c gram positive bacteria. | the gfp (green fluorescent protein) gene has previously been used to construct a variety of reporter plasmids for gram-positive bacteria for bacterial localization and gene expression studies. when a native red-shifted gfp variant (gfp3) was cloned into an expression vector using the pxyn promoter and used to transform the soil-borne pathogen listeria monocytogenes, only a small proportion of the population was seen to fluoresce when examined by epifluorescence microscopy. when the pxyn promoter ... | 2001 | 12032603 |
| contribution of hemolysin and phospholipase activity to cytolytic properties and viability of listeria monocytogenes. | the life cycle of listeria monocytogenes strongly depends on cytolysin which facilitates the pathogen's escape from the endosome. this process is very ineffective in the absence of phospholipases. in this study we investigated the molecular mechanism of cooperation between hemolysin and phospholipases. we propose a model involving interactions between proteins that increase the affinity of cytolysins for the membrane as well direct enzymatic enhancement of lysis. | 2001 | 11930992 |
| systematic mutational analysis of the amino-terminal domain of the listeria monocytogenes acta protein reveals novel functions in actin-based motility. | the listeria monocytogenes acta protein acts as a scaffold to assemble and activate host cell actin cytoskeletal factors at the bacterial surface, resulting in directional actin polymerization and propulsion of the bacterium through the cytoplasm. we have constructed 20 clustered charged-to-alanine mutations in the nh2-terminal domain of acta and replaced the endogenous acta gene with these molecular variants. these 20 clones were evaluated in several biological assays for phenotypes associated ... | 2001 | 11886549 |
| osmosensing and osmoregulatory compatible solute accumulation by bacteria. | bacteria inhabit natural and artificial environments with diverse and fluctuating osmolalities, salinities and temperatures. many maintain cytoplasmic hydration, growth and survival most effectively by accumulating kosmotropic organic solutes (compatible solutes) when medium osmolality is high or temperature is low (above freezing). they release these solutes into their environment when the medium osmolality drops. solutes accumulate either by synthesis or by transport from the extracellular med ... | 2001 | 11913457 |
| [identification of hypervariable and conservative fragments of listeria genome]. | the computer analysis revealed hypervariable and highly conservative fractions in the genes of gram-positive bacteria of the listeria genus. as a result of analysis of gene iap coding protein p60, pcr based test systems for detection of 6 listeria species, l. monocytogenes, l. seeligeri, l. ivanovii, l. innocua, l. grayi and l. welshimeri have been developed. species-specific and conservative gene fragments coding listeria pathogenicity factors, listeriolysin and cytolysin, were detected. the se ... | 2001 | 11871305 |
| hydrocephalus internus--first manifestation of chronic meningitis due to listeria monocytogenes. | 2001 | 11848049 | |
| evaluation of caesalpinia ferrea extract on bone marrow hematopoiesis in the murine models of listeriosis and ehrlich ascites tumor. | the capacity of hematopoietic tissues to produce and mobilize phagocytes to the site of infection and tumor growth is of central importance to mediate the early immunological response. in this perspective, studies from our laboratory have defined listeria monocytogenes infection and the ehrlich ascites tumor (eat) as useful models to investigate the effects of natural compounds on the growth and differentiation of granulocyte-macrophage progenitor cells (cfu-gm). as expected, a significant reduc ... | 2001 | 11694028 |
| addition of maitake d-fraction reduces the effective dosage of vancomycin for the treatment of listeria-infected mice. | maitake d-fraction, beta1,6-glucan having beta1,3-branches, has been reported to activate the immune system of the host. to elucidate whether the d-fraction can reduce the clinical effective dosage of antibiotics in the treatment of opportunistic bacterial infection, we examined the effects of d-fraction on the treatment of listeria monocytogenes-infected mice in combination with vancomycine (vcm), the only antibiotic used for methicillin-resistant staphylococcus aureus (mrsa). listeria-infectio ... | 2001 | 11829152 |
| listeria meningoencephalitis: two cases and a review of the literature. | although presently uncommon locally, listeria is increasing an important cause of central nervous system (cns) infection worldwide. it differs from the common meningitis pathogens in its clinical features and treatment. | 2001 | 11817300 |
| removal of bacterial indicators and pathogens from dairy wastewater by a multi-component treatment system. | microbial removal by a multi-component treatment system for dairy and municipal wastewater is being studied in arizona, usa. the system consists of paired solids separators, anaerobic lagoons, aerobic ponds and constructed wetlands cells. the organisms under study include: total coliform, fecal coliform, enterovirus, listeria monocytogenes, clostridium perfringens, coliphage, giardia lamblia and cryptosporidium parvum. organism removal rates from dairy wastewater varied from 13.2 per cent for fe ... | 2001 | 11804092 |
| efficacy of nisin in combination with protective cultures against listeria monocytogenes scott a in tofu. | nisin can be used as a biopreservative to control growth of listeria monocytogenes in various minimally processed foods. tofu is an example of a non-fermented soybean product, which may allow growth of listeria at refrigeration temperatures and in which nisin may be applied to prevent multiplication of listeria. the efficacy of nisin against listeria may be compromised by the emergence of spontaneous nisin-resistant mutants. exposure of l. monocytogenes scott a to nisin in a culture medium or in ... | 2001 | 11789934 |
| effect of high oxygen modified atmosphere packaging on microbial growth and sensorial qualities of fresh-cut produce. | the application of high oxygen atmospheres (hoa) (i.e. > 70% o2) for packaging ready-to-eat vegetables was evaluated as an alternative technique for low o2 equilibrium modified atmosphere (ema) packaging (3% o2-5% co2-balance n2) for respiring products. comparative experiments between both techniques were performed in-vitro and in-vivo. typical spoilage causing microorganisms (pseudomonas fluorescens, candida lambica), the moulds botrytis cinerea, aspergillus flavus and the opportunistic psychro ... | 2001 | 11789938 |
| validation of iso method 11290 part 2. enumeration of listeria monocytogenes in foods. | the european and international standard method for the enumeration of listeria monocytogenes, described in en iso 11290 part 2: 1998 [en iso 11290-2 microbiology of food and animal feedingstuffs-horizontal method for the detection and enumeration of l. monocytogenes: part 2. enumeration; international organisation for standardisation, geneva.] was validated by order of the european commission (standards, measurement and testing fourth framework programme project smt4-ct96-2098). the objective wa ... | 2001 | 11759750 |
| the effect of inoculum size on the lag phase of listeria monocytogenes. | the effect of inoculum size on population lag times of listeria monocytogenes was investigated using the bioscreen automated microtitre plate incubator and reader. under optimum conditions, lag times were little affected by inoculum size and there was little variation between replicate inocula even at very low cell numbers. however, in media containing inhibitory concentrations of nacl, both the mean lag time and variation between replicate inocula increased as the inoculum size became smaller. ... | 2001 | 11759754 |
| occurrence of listeria monocytogenes in food in chile. | out of 2145 food samples analysed 77 were found contaminated with listeria monocytogenes in santiago, chile. samples were: 603 ice-cream (3.5% contaminated), 256 soft cheese (0.8%), 155 hard cheese (0%), 229 baby milk bottles (0%), 634 processed meat products (3.6%) and 268 crustaceous shellfish (11.6%). three different isolation media were used: for 318 samples, modified mcbride agar (mma), lithium chloride phenylethanol moxalactam agar, and polymyxin acriflavine lithium chloride ceftazidime ae ... | 2001 | 11759755 |
| prevalence and characteristics of shigatoxin-producing escherichia coli and listeria monocytogenes strains isolated from minced meat in switzerland. | a total of 400 minced meat samples from 240 small butcheries in switzerland were collected and analysed for the presence of shigatoxin-producing e. coli (stec) and listeria monocytogenes. the samples comprised 211 samples of minced beef and 189 samples of minced pork. shigatoxin-producing e. coli was isolated from 7/400 (1.75%) samples. in particular, 5/211 (2.3%) minced beef samples and 2/189 (1%) minced pork samples were contaminated. serotyping of the seven strains yielded five different sero ... | 2001 | 11759763 |
| exposure of listeria monocytogenes within an epidemic caused by butter in finland. | data on the levels of bacteria and the amounts of food consumed in food-borne outbreaks provides an excellent opportunity to study the effects of exposure to listeria monocytogenes. between june 1998 and april 1999, an outbreak caused by l. monocytogenes serotype 3a in butter occurred in finland. the majority of the cases were immunocompromised and hospitalized at the helsinki university central hospital (huch), where 7-g butter packages produced by a dairy plant were used as the only butter bra ... | 2001 | 11759767 |
| food-borne listeria monocytogenes risk assessment. | listeria monocytogenes is ubiquitous in the environment and in food processing plants. consequently, foods are frequently contaminated. however, the occurrence rate of listeriosis is only about five cases per million people per year. listeriosis primarily strikes immunocompromised individuals, pregnant women and the elderly with a fatality rate of 20-25%. the fda is in the process of finishing a risk assessment that is being conducted as an initial step in reviewing its approach to maximizing th ... | 2001 | 11761122 |
| an approach towards public health and foodborne human listeriosis--the austrian listeria monitoring. | the institute for milk hygiene, milk technology and food science has launched a listeria monitoring for austrian cheese factories in 1988 which is nowadays a valuable tool to control the safety of cheese production. it is a means to qualify the proper hygienic conditions in the participating cheese plants. proper hygiene protects cheese plants from getting contaminated by l. monocytogenes. the preventive elimination of foodborne pathogens facilitates a thriving economical development of the dome ... | 2001 | 11766273 |
| listeria spinal cord abscess responsive to trimethoprim-sulfamethoxazole monotherapy. | to describe an alternative antibiotic regimen for the treatment of central nervous system listeria monocytogenes infection. | 2001 | 11766781 |
| a retrospective study of neonatal mortality in farmed elk. | despite the increasing importance of the canadian elk industry, the veterinary literature concerning diseases of elk is sparse, in particular for the neonatal period. this study summarizes necropsy findings in 111 farmed elk calves, up to 30 days of age, submitted to the diagnostic laboratory of the western college of veterinary medicine over a 9-year period (990 to 1998). causes of mortality fit into 3 categories: infectious disease, noninfectious disease, and undetermined. organisms causing di ... | 2001 | 11769617 |
| inactivation of escherichia coli o157: h7 and listeria monocytogenes by pr-26, a synthetic antibacterial peptide. | this study reports the antibacterial effect of pr-26, a synthetic peptide derived from the first 26 amino acid sequence of pr-39, an antimicrobial peptide isolated from porcine neutrophils. a three-strain mixture of escherichia coli o157:h7 or listeria monocytogenes of approximately 10(8) cfu was inoculated to a final concentration of 10(7) cfu/ml in 1% peptone water (ph 7.0), containing 50 or 75 microg/ml of pr-26, and incubated at 37 degrees c for 0, 6, 12, and 24 h; at 24 degrees c for 0, 12, ... | 2001 | 11770619 |
| antimicrobials in the formulation to control listeria monocytogenes postprocessing contamination on frankfurters stored at 4 degrees c in vacuum packages. | postprocessing contamination of cured meat products with listeria monocytogenes during slicing and packaging is difficult to avoid, and thus, hurdles are needed to control growth of the pathogen during product storage. this study evaluated the influence of antimicrobials, included in frankfurter formulations, on l. monocytogenes populations during refrigerated (4 degrees c) storage of product inoculated (10(3) to 10(4) cfu/cm2) after peeling of casings and before vacuum packaging. frankfurters w ... | 2001 | 11770622 |
| efficacy of cetylpyridinium chloride in immersion treatment for reducing populations of pathogenic bacteria on fresh-cut vegetables. | the efficacy of cetylpyridinium chloride (cpc) immersion to reduce the numbers of three pathogenic bacteria (listeria monocytogenes, salmonella typhimurium, and escherichia coli o157:h7) on three different fresh-cut vegetables (broccoli, cauliflower, and radishes) was studied. the fresh-cut vegetables were inoculated with one of the three pathogenic bacteria at a concentration of 10(5) cfu/ml for 1 h at room temperature and then treated with 0.1 or 0.5% cpc immersion for 1 min. both salmonella t ... | 2001 | 11770641 |
| prevalence and contamination levels of listeria monocytogenes in smoked fish and pâté sold in spain. | from march to november 2000, 170 samples of smoked fish and 182 samples of pâté for sale in retail outlets and supermarkets in the nine provinces of castilla and león (spain) were analyzed for the prevalence of listeria monocytogenes and other listeria spp. l. monocytogenes was isolated from 38 (22.3%) of the 170 samples of smoked fish analyzed. twenty of these positive samples contained l. monocytogenes at >100 cfu/g. other listeria spp., such as listeria innocua (26 isolates), listeria grayi ( ... | 2001 | 11770642 |
| congenital nemaline myopathy due to acta1-gene mutation and carnitine insufficiency: a case report. | a premature boy with a congenital form of nemaline myopathy due to mutation in the acta1-gene showed decreased carnitine levels in the eighth week of life. after sufficient oral carnitine substitution he improved gradually. in the first 15 months of life he made good progress; he reached full head control, learned to sit unsupported and was able to raise objects. at that time the carnitine levels were normal without substitution. nemaline myopathy is clinically and genetically heterogenous. the ... | 2001 | 11748499 |
| immunomodulatory effects of dietary lipids alter host natural resistance of mice to listeria monocytogenes infection. | over the past two decades, unsaturated fatty acids have received particular attention due to their ability to suppress immune functions. nevertheless, suppression of immune functions also involves a reduction of host natural resistance to eliminate the infectious agents. we have analyzed the role of dietary lipids on immune functions in cells cultured with listeria monocytogenes. bactericidal efficiency of peritoneal cells from mice fed a fish oil diet against this bacterium was reduced and the ... | 2001 | 11750222 |
| early translocation of acid-adapted listeria monocytogenes during enteric infection in tnf/ltalpha-/- mice. | tnf/ltalpha deficient mice are devoid of peyer's patches and lack mesenteric lymph nodes. translocation, especially in the early steps after intragastric delivery of listeria monocytogenes, has been explored in this study, and the role of tnfalpha has been addressed. we showed that l. monocytogenes translocation occurred at least as efficiently in tnf/ltalpha-/- mice as in tnf/ltalpha+/+ littermates. even very low inocula (2.7x10(4) cfu) could initiate infection in the tnf/ltalpha deficient mice ... | 2001 | 11750799 |
| puma-g, an ifn-gamma-inducible gene in macrophages is a novel member of the seven transmembrane spanning receptor superfamily. | ifn-gamma is a key immunoregulatory cytokine that plays a predominant role in innate immunity. by employing pcr-select to search for genes differentially expressed in ifn-gamma/tnf-alpha stimulated macrophages, we identified a novel ifn-gamma-induced transcript designated puma-g (protein up-regulated in macrophages by ifn-gamma). puma-g codes for a protein with seven transmembrane helices, a feature commonly shared with the g protein-coupled receptor superfamily (gpcr). the puma-g protein is mos ... | 2001 | 11745392 |
| effect of prevention measures on incidence of human listeriosis, france, 1987-1997. | to assess the impact of preventive measures by the food industry, we analyzed food monitoring data as well as trends in the incidence of listeriosis estimated through three independent sources: the national reference center of listeriosis; a laboratory-based active surveillance network; and two consecutive nationwide surveys of public hospital laboratories. from 1987 to 1997, the incidence of listeriosis decreased by an estimated 68%. a substantial reduction in the proportion of listeria monocyt ... | 2001 | 11747725 |
| detection and identification of spotted fever group rickettsiae and ehrlichiae in african ticks. | rickettsia africae, a recently identified pathogen, was detected for the first time in amblyomma ticks from niger, mali, burundi, and sudan, and "r. mongolotimonae" was identified for the first time in africa. rickettsiae of unknown pathogenicity and two new ehrlichiae of the ehrlichia canis group were identified in ticks from mali and niger. | 2001 | 11747731 |
| [listeria monocytogenes infections in the adult. clinical and microbiological issues of a changing disease]. | thirty-one cases of human listeriosis seen from 1971-1999 were reviewed. cases were grouped as follows: group i composed of 14 patients were studied in the period 1971-1984; and group ii composed of 17 cases studied in the period 1985-1999. we tried to assess changes in the incidence, clinical findings and outcome in both periods. the incidence of listeriosis remained constant along the years, 1.2 cases/20,000 discharges. the mean age of the patients significantly increased along the years (55 1 ... | 2001 | 11747787 |
| microbial genomics. dynamic duos. | 2001 | 11728863 | |
| lifestyles of the intracellular. | 2001 | 11728864 | |
| actin-based motility of intracellular microbial pathogens. | a diverse group of intracellular microorganisms, including listeria monocytogenes, shigella spp., rickettsia spp., and vaccinia virus, utilize actin-based motility to move within and spread between mammalian host cells. these organisms have in common a pathogenic life cycle that involves a stage within the cytoplasm of mammalian host cells. within the cytoplasm of host cells, these organisms activate components of the cellular actin assembly machinery to induce the formation of actin tails on th ... | 2001 | 11729265 |
| first report of an outbreak of ovine septicaemic listeriosis in saudi arabia. | although a case of human listeriosis has recently been reported in saudi arabia, the disease has not been reported in animals to date. the authors describe an outbreak of septicaemic listeriosis in sheep, which occurred during winter. adult animals and pregnant ewes were principally affected, with a morbidity rate of 7.1% and a mortality rate of 2.4%; no abortions were recorded during the outbreak. clinical signs included inappetence, weakness, fever, respiratory distress, keratoconjunctivitis a ... | 2001 | 11732420 |
| [notification according to the law for protection against infections]. | since january 1st 2001, the law for protection against infections decrees the duty of notification along two tracks, on the one hand by notification of infectious diseases and on the other hand by reporting the pathogens. however, the names of pathogens change due to scientific progress. furthermore, these names include in some cases not only harmful agents of infectious diseases but also inoffensive organisms, i. e. giardia lamblia. there are also problems in the notification of other pathogens ... | 2001 | 11735068 |
| sample preparation methods for pcr detection of escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes on beef chuck shoulder using a single enrichment medium. | to improve the utility of the polymerase chain reaction (pcr) for food samples, methods for preparing template dna were developed to remove pcr inhibitors. beef chuck shoulder medallions, artificially contaminated, individually or in combination, with escherichia coli serotype o157:h7 strain fsis 45753-35, salmonella typhimurium dt104 strain 13hp, or listeria monocytogenes strain scott a at concentrations of 10, 1 and 0.5 cfu/cm(2)were swabbed with a sponge, and the sponges were enriched for 18 ... | 2001 | 11735298 |
| rapid detection of listeria monocytogenes in foods, by a combination of pcr and dna probe. | listeria monocytogenes is a frequent contaminant of water and foods. its rapid detection is needed before some foods can be prepared for marketing. in this work l. monocytogenes has been searched for in foods, by a combination of polymerase chain reaction (pcr) and a dna probe. both pcr and the probe were prepared for recognizing a specific region of the internalin gene, which is responsible for the production of one of the most important pathogenic factors of listeria. the combined use of pcr a ... | 2001 | 11735299 |
| bacterial meningitis: current controversies in approaches to treatment. | acute bacterial meningitis continues to be a disease with unacceptably high mortality and morbidity rates in both adults and children worldwide, despite advances in antibacterial therapy. death or permanent disability occurs frequently. the causative organism varies with age, immune function and immunisation status. infection with neisseria meningitidis, streptococcus pneumoniae and haemophilus influenzae type b (hib) is associated with the majority of cases, with listeria monocytogenes and stre ... | 2001 | 11735611 |
| a role for acta in epithelial cell invasion by listeria monocytogenes. | we assessed the role of the actin-polymerizing protein, acta, in host cell invasion by listeria monocytogenes. an in frame deltaacta mutant was constructed in a hyperinvasive strain of prfa* genotype, in which all genes of the prfa-dependent virulence regulon, including acta, are highly expressed in vitro. loss of acta production in prfa* bacteria reduced entry into caco-2, hela, mdck and vero epithelial cells to basal levels. reintroduction of acta into the deltaacta prfa* mutant fully restored ... | 2001 | 11736996 |
| synergy between the n- and c-terminal domains of inlb for efficient invasion of non-phagocytic cells by listeria monocytogenes. | inlb is a listeria monocytogenes protein promoting entry in non-phagocytic cells, and has been shown recently to activate the hepatocyte growth factor receptor (hgfr or met). the n-terminal domain of inlb (lrrs) binds and activates met, whereas the c-terminal domain of inlb (gw modules) mediates loose attachment of inlb to the listerial surface. as hgf activation of met is tightly controlled by glycosaminoglycans (gags), we tested if gags also modulate the met-inlb interactions. we show that inl ... | 2001 | 11737639 |
| endogenous serratia marcescens endophthalmitis with dark hypopyon: case report and review. | a case of endogenous serratia marcescens endophthalmitis in a patient with diabetes, end-stage renal disease, and an indwelling venous catheter is reported. the patient presented with a tan hypopyon and elevated intraocular pressure. diagnosis was established by positive blood, vitreous, conjunctival, and catheter tip cultures. after a deteriorating course the eye was enucleated. gross and histopathologic examination revealed the presence of a dark hypopyon with iris necrosis and pigment dispers ... | 2001 | 11738433 |
| immunoproteasomes largely replace constitutive proteasomes during an antiviral and antibacterial immune response in the liver. | the proteasome is critically involved in the production of mhc class i-restricted t cell epitopes. proteasome activity and epitope production are altered by ifn-gamma treatment, which leads to a gradual replacement of constitutive proteasomes by immunoproteasomes in vitro. however, a quantitative analysis of changes in the steady state subunit composition of proteasomes during an immune response against viruses or bacteria in vivo has not been reported. here we show that the infection of mice wi ... | 2001 | 11739503 |
| a sigma(54)-dependent pts permease of the mannose family is responsible for sensitivity of listeria monocytogenes to mesentericin y105. | sensitivity of listeria monocytogenes to the bacteriocin mesentericin y105 was previously shown to be dependent on the sigma(54) subunit of the rna polymerase. this points towards expression of particular sigma(54)-dependent genes. the present study describes first, manr, a new sigma(54)-associated activator, and second, ell(t)(man), a new sigma(54)-dependent pts permease of the mannose family, both involved in sensitivity to mesentericin y105, since interruption of their corresponding genes led ... | 2001 | 11739758 |
| uva exposure affects uvb and cis-urocanic acid-induced systemic suppression of immune responses in listeria monocytogenes-infected balb/c mice. | ultraviolet radiation can inhibit immune responses locally as well as systemically. such effects have been measured in animals and humans exposed to ultraviolet b (wavelength 280-315 nm) (uvb) and ultraviolet a (315-400 nm) (uva). the precise wavelength dependence is important for the identification of possible molecular targets and for assessments of risk of different artificial uv sources and solar uv. in such analyses, it is commonly assumed that radiation energy from each wavelength contribu ... | 2001 | 11332040 |
| evolution and function of the neisserial dam-replacing gene. | phase variation through slippage-like mechanisms involving homopolymeric tracts depends in part on the absence of dam-methylase in several pathogenic isolates of neisseria meningitidis. in dam-defective strains drg (dam-replacing gene), flanked by pseudo-transposable small repeated elements (sres), replaced dam. we demonstrate that drg encodes a restriction endonuclease (nmebii) that cleaves 5'-gmeatc-3'. drg is also present in 50% of neisseria lactamica strains, but in most of them it is inacti ... | 2001 | 11334887 |
| stimulation of myelopoiesis in listeria monocytogenes-infected mice by an aggregated polymer isolated from aspergillus oryzae. | in this work, we investigated the effects of the proteic aggregated polymer of magnesium ammonium phospholinoleate-palmitoleate anhydride (mapa) isolated from aspergillus oryzae on the growth and differentiation of bone marrow granulocyte-macrophage progenitor cells (cfu-gm) in listeriamonocytogenes-infected mice. a significant reduction in the cfu-gm number was observed in the initial phase of infection with a sublethal dose of listeria. treatment of mice with 0.5, 2.0 and 5.0 mg/kg mapa for 7 ... | 2001 | 11339624 |
| cutting edge: antigen-independent cd8 t cell proliferation. | recent analyses of cd8 t cell responses to listeria monocytogenes infection demonstrate that the duration of in vivo t cell proliferation is not determined by the amount or duration of ag presentation. however, the extent to which t lymphocytes are capable of proliferating in the absence of ag is unknown. herein we demonstrate that cd8 t lymphocytes undergo up to eight rounds of proliferation in the absence of ag following transient, 2.5-h in vitro antigenic stimulation. ag-independent expansion ... | 2001 | 11342598 |
| pregnant women get no bologna--or shark or brie. | 2001 | 11211338 | |
| two novel genes find and lind differentially expressed in deactivated and listeria-infected human macrophages. | deactivation of macrophage functions plays an important role in human infectious and inflammatory diseases. in this study, differential-display rt-pcr was used to analyze the gene expression of human mononuclear phagocytes deactivated with interleukin (il)-4, il-10, and dexamethasone (dex), in the absence and presence of infection with listeria monocytogenes (listeria). two novel differentially expressed mrna species were discovered: find (il-four induced) was upregulated with il-4 but down-regu ... | 2001 | 11345586 |
| phagocytosis and clearance of apoptotic cells is mediated by mer. | apoptosis is fundamental to the development and maintenance of animal tissues and the immune system. rapid clearance of apoptotic cells by macrophages is important to inhibit inflammation and autoimmune responses against intracellular antigens. here we report a new function for mer, a member of the axl/mer/tyro3 receptor tyrosine kinase family. mer(kd) mice with a cytoplasmic truncation of mer had macrophages deficient in the clearance of apoptotic thymocytes. this was corrected in chimaeric mic ... | 2001 | 11346799 |
| the acid-stress response in lactobacillus sanfranciscensis cb1. | lactobacillus sanfranciscensis cb1, an important sourdough lactic acid bacterium, can withstand low ph after initial exposure to sublethal acidic conditions. the sensitivity to low ph varied according to the type of acid used. treatment of lb: sanfranciscensis cb1 with chloramphenicol during acid adaptation almost completely eliminated the protective effect, suggesting that induction of protein synthesis was required for the acid-tolerance response. two constitutively acid-tolerant mutants, cb1- ... | 2001 | 11429463 |
| listeria pathogenesis and molecular virulence determinants. | the gram-positive bacterium listeria monocytogenes is the causative agent of listeriosis, a highly fatal opportunistic foodborne infection. pregnant women, neonates, the elderly, and debilitated or immunocompromised patients in general are predominantly affected, although the disease can also develop in normal individuals. clinical manifestations of invasive listeriosis are usually severe and include abortion, sepsis, and meningoencephalitis. listeriosis can also manifest as a febrile gastroente ... | 2001 | 11432815 |
| the effect of inoculum size and sublethal injury on the ability of listeria monocytogenes to initiate growth under suboptimal conditions. | to investigate the effect of inoculum size and physiological state on the ability of listeria monocytogenes cells to initiate growth under suboptimal conditions of salt concentration and ph. | 2001 | 11696096 |
| evaluation of a spray-dried lacticin 3147 powder for the control of listeria monocytogenes and bacillus cereus in a range of food systems. | the potential of a powdered preparation of the bacteriocin, lacticin 3147, was investigated for the inhibition of listeria monocytogenes and bacillus cereus. | 2001 | 11696102 |
| listeria monocytogenes infection overcomes the requirement for cd40 ligand in exogenous antigen presentation to cd8(+) t cells. | in vivo priming of cd8(+) t lymphocytes against exogenously processed model ags requires cd4(+) t cell help, specifically interactions between cd40 ligand (cd40l) expressed by activated cd4(+) t cells and cd40, which is present on professional apc such as dendritic cells (dcs). to address this issue in the context of bacterial infection, we examined cd40l-cd40 interactions in cd8(+) t cell priming against an exogenously processed, nonsecreted bacterial ag. cd40l interactions were blocked by in v ... | 2001 | 11698431 |
| role of cd28 for the generation and expansion of antigen-specific cd8(+) t lymphocytes during infection with listeria monocytogenes. | infection of mice with the intracellular bacterium listeria monocytogenes results in a strong cd8(+) t cell response that is critical for efficient control of infection. we used cd28-deficient mice to characterize the function of cd28 during listeria infection, with a main emphasis on listeria-specific cd8(+) t cells. frequencies and effector functions of these t cells were determined using mhc class i tetramers, single cell ifn-gamma production and listeria-specific cytotoxicity. during primary ... | 2001 | 11698433 |
| prevalence of foodborne pathogens in bulk tank milk. | bulk tank milk from 131 dairy herds in eastern south dakota and western minnesota was examined for the presence of for foodborne pathogens. campylobacter jejuni, shiga-toxin producing escherichia coli, listeria monocytogenes, salmonella spp., and yersinia enterocolitica were detected in 9.2, 3.8, 4.6, 6.1, and 6.1% of bulk tank milk samples, respectively. thirty-five of 131 (26.7%) bulk tank milk samples contained one or more species of pathogenic bacteria. isolates of salmonella belonged to gro ... | 2001 | 11699446 |
| two consecutive nationwide outbreaks of listeriosis in france, october 1999-february 2000. | in france, listeriosis surveillance is based on mandatory notification of all culture-confirmed cases, with systematic typing of isolates and routine collection of the patient's food history. from october 1999 to march 2000, two outbreaks of listeriosis were detected through this enhanced surveillance system. in outbreak 1, analysis of the food histories of cases suggested brand x "rillettes," a pâté-like meat product, as the vehicle of infection, and the outbreak strain of listeria monocytogene ... | 2001 | 11700249 |
| svpa, a novel surface virulence-associated protein required for intracellular survival of listeria monocytogenes. | a previously unknown protein, designated svpa (surface virulence-associated protein) and implicated in the virulence of the intracellular pathogen listeria monocytogenes, was identified. this 64 kda protein, encoded by svpa, is both secreted in culture supernatants and surface-exposed, as shown by immunogold labelling of whole bacteria with an anti-svpa antibody. analysis of the peptide sequence revealed that svpa contains a leader peptide, a predicted c-terminal transmembrane region and a posit ... | 2001 | 11700342 |
| intestinal infection of balb/c mice with yersinia enterocolitica o9 causes major modifications in phenotype and functions of spleen cells. | yersinia enterocolitica serotype o9 may cause a persistent intestinal infection with few or no symptoms in humans and in balb/c mice. the present study demonstrated profound alterations in the immune status of balb/c mice infected with y. enterocolitica o9. infected mice developed splenomegaly and phenotypic analysis of spleen cells revealed increases in cd3+ total t cells, cd4+ helper t cells, cd8+ cytotoxic t cells and cd11b+ phagocytic cells. spleen cells from infected mice exhibited impaired ... | 2001 | 11700368 |
| exaggerated proinflammatory and th1 responses in the absence of gamma/delta t cells after infection with listeria monocytogenes. | while gamma/delta t cells are involved in host defense and immunopathology in a variety of infectious diseases, their precise role is not yet clearly defined. in the absence of gamma/delta t cells, mice die after infection with a dose of listeria monocytogenes that is not lethal in immunologically intact animals. morbidity might result from insufficient levels of cytokines normally produced by gamma/delta t cells or conversely from an excess of cytokines due to a lack of down-regulation of the i ... | 2001 | 11705890 |
| effect of 6-hydroxydopamine on host resistance against listeria monocytogenes infection. | recent studies have shown that immunocompetent cells bear receptors of neuropeptides and neurotransmitters and that these ligands play roles in the immune response. in this study, the role of the sympathetic nervous system in host resistance against listeria monocytogenes infection was investigated in mice pretreated with 6-hydroxydopamine (6-ohda), which destroys sympathetic nerve termini. the norepinephrine contents of the plasma and spleens were significantly lower in 6-ohda-treated mice than ... | 2001 | 11705892 |
| tolerance or immunity to a tumor antigen expressed in somatic cells can be determined by systemic proinflammatory signals at the time of first antigen exposure. | mice transgenic for the e7 tumor ag of human papillomavirus type 16, driven from a keratin 14 promoter, express e7 in keratinocytes but not dendritic cells. grafted e7-transgenic skin is not rejected by e7-immunized mice that reject e7-transduced transplantable tumors. rejection of recently transplanted e7-transgenic skin grafts, but not of control nontransgenic grafts or of established e7-transgenic grafts, is induced by systemic administration of live or killed listeria monocytogenes or of end ... | 2001 | 11714778 |
| two listeria monocytogenes vaccine vectors that express different molecular forms of human papilloma virus-16 (hpv-16) e7 induce qualitatively different t cell immunity that correlates with their ability to induce regression of established tumors immortalized by hpv-16. | two recombinant listeria monocytogenes (rlm) strains were produced that secrete the human papilloma virus-16 (hpv-16) e7 protein expressed in hpv-16-associated cervical cancer cells. one, lm-e7, expresses and secretes e7 protein, whereas a second, lm-llo-e7, secretes e7 as a fusion protein joined to a nonhemolytic listeriolysin o (llo). lm-llo-e7, but not lm-e7, induces the regression of the e7-expressing tumor, tc-1, established in syngeneic c57bl/6 mice. both recombinant e7-expressing rlm vacc ... | 2001 | 11714814 |
| immunization with gp96 from listeria monocytogenes-infected mice is due to n-formylated listerial peptides. | n-formylated (n-f-met) peptides derived from proteins of the intracellular bacterium listeria monocytogenes generate a protective, h2-m3-restricted cd8 t cell response in c57bl/6 mice. n-f-met peptide-specific ctl were generated in vitro when mice previously immunized with gp96 isolated from donor mice infected with l. monocytogenes were stimulated with these peptides. no significant peptide-specific ctl activity was observed in mice immunized with gp96 from uninfected animals. masses correspond ... | 2001 | 11714815 |
| prevalence and characterization of listeria monocytogenes in the feces of healthy austrians. | the aims of the study were to determine the prevalence of listeria monocytogenes in the feces of healthy austrians and to characterize the isolates by various typing methods. stool specimens from 505 healthy volunteers from the tyrol were tested for the presence of l. monocytogenes using cold enrichment for 6 months and five different detection methods: conventional plating onto palcam and rapid'l.mono agar, immunomagnetic separation (ims) followed by conventional plating, enzyme-linked fluoresc ... | 2001 | 11715752 |
| detection of listeria monocytogenes by polymerase chain reaction oriented to inlb gene. | primers were designed for the detection of listeria monocytogenes by the polymerase chain reaction oriented to specific sequences of the inlb gene encoding an internalin. at optimized reaction conditions, 100% sensitivity (on a panel of 33 strains of l. monocytogenes) and 100% specificity (on panels of 15 strains of other listeria spp. and 41 other bacteria), were determined for the inlb-l/r primers. the detection limit of pcr with these primers was 10(4) cfu/ml and was not affected by up to 10( ... | 2001 | 11718370 |
| cloning and characterization of m.lmoa118i, a novel dna:m4c methyltransferase from the listeria monocytogenes phage a118, a close homolog of m.ngomxv. | a homolog of m.ngomxv dna:m4c methyltransferase has been identified among the open reading frames deduced from the genomic sequence of listeria monocytogenes phage a118 [loessner et al., 2000]. the gene coding for this putative protein has been cloned in escherichia coli and its enzymatic activity in vivo in this host have been analyzed. remarkably, despite m.ngomxv and m.lmoa118i exhibit high sequence similarity (58% identical and 19% conservatively substituted residues), their target preferenc ... | 2001 | 11720310 |
| uptake and killing of listeria monocytogenes by normal human peripheral blood granulocytes and monocytes as measured by flow cytometry and cell sorting. | cellular components of innate immunity (nk cells, monocytes and granulocytes) play an important role in early resistance to listeria monocytogenes in the mouse model. minimally invasive methods of measuring the bacteriocidal capacity of these cells may be useful as a biomarker of susceptibility in humans. a technique was developed whereby the uptake and survival of l. monocytogenes could be measured in human granulocytes and monocytes using small volumes of peripheral blood. this method used flo ... | 2001 | 11720818 |
| effects of intermediate filaments on actin-based motility of listeria monocytogenes. | how does subcellular architecture influence the intracellular movements of large organelles and macromolecular assemblies? to investigate the effects of mechanical changes in cytoplasmic structure on intracellular motility, we have characterized the actin-based motility of the intracellular bacterial pathogen listeria monocytogenes in normal mouse fibroblasts and in fibroblasts lacking intermediate filaments. the apparent diffusion coefficient of l. monocytogenes was two-fold greater in vimentin ... | 2001 | 11720985 |
| priming of memory but not effector cd8 t cells by a killed bacterial vaccine. | killed or inactivated vaccines targeting intracellular bacterial and protozoal pathogens are notoriously ineffective at generating protective immunity. for example, vaccination with heat-killed listeria monocytogenes (hklm) is not protective, although infection with live l. monocytogenes induces long-lived, cd8 t cell-mediated immunity. we demonstrate that hklm immunization primes memory cd8 t lymphocyte populations that, although substantial in size, are ineffective at providing protection from ... | 2001 | 11721060 |
| an antibody-immobilized capillary column as a bioseparator/bioreactor for detection of escherichia coil o157:h7 with absorbance measurement. | a capillary-column-based bioseparator/bioreactor was developed for detection of escherichia coli o157:h7 by chemically immobilizing anti-e. coli o157:h7 antibodies onto the inner wall of the column, forming the "sandwich" immunocomplexes (immobilized antibody-e. coli o157: h7-enzyme-labeled antibody) after the sample and the enzyme-labeled antibody passed through the column and detecting the absorbance of the product in the bioreactor with an optical detector. the effects of the blocking agent, ... | 2001 | 11721916 |
| behaviour of listeria monocytogenes in packaged fresh mushrooms (agaricus bisporus). | the aim of this study was to evaluate the potential of listeria monocytogenes to grow in mushrooms packaged in two different types of pvc films when stored at 4 degrees c and 10 degrees c. | 2001 | 11722656 |
| adsorption of biosurfactant on solid surfaces and consequences regarding the bioadhesion of listeria monocytogenes lo28. | the influence of biosurfactant compounds produced by a strain of pseudomonas fluorescens on the adhesion of listeria monocytogenes lo28 to polytetrafluoroethylene (ptfe) and aisi 304 stainless steel surfaces was investigated. | 2001 | 11722659 |
| molecular epidemiology of listeria monocytogenes isolates collected from the environment, raw meat and raw products in two poultry- and pork-processing plants. | in order to study the transmission of listeria monocytogenes in a poultry and a pork meat plant, we analysed the contamination by this pathogen over several months. | 2001 | 11722667 |
| listeria keratitis in a horse. | listeria monocytogenes is ubiquitous in the environment but is rarely reported as a cause of keratitis in animals. in this case, a mare was presented with epiphora and evidence of pain in the right eye. listeria monocytogenes was isolated from a corneal lesion, and bacteria were also seen in the cytologic evaluation. this is the first reported case of ulcerative keratitis associated with l. monocytogenes in a horse. | 2001 | 11722787 |
| molecular typing by pulsed-field gel electrophoresis of spanish animal and human listeria monocytogenes isolates. | a total of 153 strains of listeria monocytogenes isolated from different sources (72 from sheep, 12 from cattle, 18 from feedstuffs, and 51 from humans) in spain from 1989 to 2000 were characterized by pulsed-field gel electrophoresis. the strains of l. monocytogenes displayed 55 pulsotypes. the 84 animal, 51 human, and 18 feedstuff strains displayed 31, 29, and 7 different pulsotypes, respectively, indicating a great genetic diversity among the spanish l. monocytogenes isolates studied. l. mono ... | 2001 | 11722943 |
| validation of apple cider pasteurization treatments against escherichia coli o157:h7, salmonella, and listeria monocytogenes. | time and temperature pasteurization conditions common in the wisconsin cider industry were validated using a six-strain cocktail of escherichia coli o157:h7 and acid-adapted e. coli o157:h7 in ph- and degrees brix-adjusted apple cider. strains employed were linked to outbreaks (atcc 43894 and 43895, c7927, and usda-fsis-380-94) or strains engineered to contain the gene for green fluorescent protein (pgfp atcc 43894 and pgfp atcc 43889) for differential enumeration. survival of salmonella spp. (c ... | 2001 | 11726144 |
| organic acids and their salts as dipping solutions to control listeria monocytogenes inoculated following processing of sliced pork bologna stored at 4 degrees c in vacuum packages. | postprocessing contamination of cured meats with listeria monocytogenes has become a major concern for the meat processing industry and an important food safety issue. this study evaluated aqueous dipping solutions of organic acids (2.5 or 5% lactic or acetic acid) or salts (2.5 or 5% sodium acetate or sodium diacetate, 5 or 10% sodium lactate, 5% potassium sorbate or potassium benzoate) to control l. monocytogenes on sliced, vacuum-packaged bologna stored at 4 degrees c for up to 120 days. orga ... | 2001 | 11726150 |
| reduction of listeria monocytogenes on green peppers (capsicum annuum l.) by gaseous and aqueous chlorine dioxide and water washing and its growth at 7 degrees c. | reduction of listeria monocytogenes scott a on uninjured and injured surfaces of green peppers after 0.3- and 3-mg/ liter gaseous and aqueous clo2 treatment and water washing for 10 min at 20 degrees c was studied. growth of the l. monocytogenes untreated or treated with 0.6 mg/liter clo2 gas for 30 min at 20 degrees c on green peppers also was investigated. a membrane-surface-plating method was used for resuscitation and enumeration of l monocytogenes treated with clo2. the bacterial viability ... | 2001 | 11726151 |
| detection of heat injury in listeria monocytogenes scott a. | methods of detecting live pathogens in foods that may be growth inhibited following heat treatment are essential to food safety. among the techniques available, reverse transcription polymerase chain reaction (rt-pcr) amplification of messenger rna from heat-injured listeria monocytogenes scott a is preferable to direct pcr in an attempt to avoid false positives from dead cells. the rt-pcr has a detection limit of 3 x 10(6) cfu/g, compared to 3 cfu/g for untreated controls, but may not be suitab ... | 2001 | 11726152 |
| combination of immunomagnetic separation and polymerase chain reaction for the simultaneous detection of listeria monocytogenes and salmonella spp. in food samples. | a method that combined the immunomagnetic separation (ims) technique and the multiplex polymerase chain reaction (pcr) method (i.e., the ims-mpcr method) was developed for simultaneous detection of listreria monocytogenes and salmonella spp. in food samples. when only the multiplex pcr method was used, it was found that if cell numbers of each of the two target organisms (l. monocytogenes and salmonella spp.) were above the detection limit, but differed by more than 2 logs-e.g., n x 10(7) to n x ... | 2001 | 11726153 |
| evaluation of universal preenrichment broth for growth of heat-injured pathogens. | universal preenrichment broth (upb) was developed to enable enrichment of injured foodborne pathogens of different genera simultaneously in lieu of having to undergo separate simultaneous enrichment cultures for subsequent detection or isolation of each pathogen. enrichment conditions in upb for growth of injured pathogens to populations that will enable pathogen detection by rapid immuno-based or polymerase chain reaction (pcr)-based assays have not been defined. hence, studies were done to det ... | 2001 | 11726154 |
| intracellular antibody neutralizes listeria growth. | we previously reported that treatment of mice with a neutralizing mab against listeriolysin o (llo), the pore-forming toxin of listeria monocytogenes, provided resistance to this intracellular bacterium. we evaluated whether anti-llo mab would affect listeria handling by macrophages, essential cells in listeria resistance. macrophages infected in the presence of anti-llo mab showed a marked reduction in intracellular listeria growth, with a concomitant block in llo-dependent listeria passage fro ... | 2001 | 11371353 |
| influence of the natural microbial flora on the acid tolerance response of listeria monocytogenes in a model system of fresh meat decontamination fluids. | depending on its composition and metabolic activity, the natural flora that may be established in a meat plant environment can affect the survival, growth, and acid tolerance response (atr) of bacterial pathogens present in the same niche. to investigate this hypothesis, changes in populations and atr of inoculated (10(5) cfu/ml) listeria monocytogenes were evaluated at 35 degrees c in water (10 or 85 degrees c) or acidic (2% lactic or acetic acid) washings of beef with or without prior filter s ... | 2001 | 11375145 |
| survival and heat resistance of listeria monocytogenes after exposure to alkali and chlorine. | a strain of listeria monocytogenes isolated from a drain in a food-processing plant was demonstrated, by determination of d values, to be more resistant to the lethal effect of heat at 56 or 59 degrees c following incubation for 45 min in tryptose phosphate broth (tpb) at ph 12.0 than to that of incubation for the same time in tpb at ph 7.3. cells survived for at least 6 days when they were suspended in tpb at phs 9.0, 10.0, and 11.0 and stored at 4 or 21 degrees c. cells of l. monocytogenes inc ... | 2001 | 11375163 |
| identification and disruption of the proba locus in listeria monocytogenes: role of proline biosynthesis in salt tolerance and murine infection. | intracellular accumulation of the amino acid proline has previously been linked to the salt tolerance and virulence potential of a number of bacteria. taking advantage of the proba mutant escherichia coli csh26, we identified a listerial proba operon coding for enzymes functionally similar to the glutamyl kinase (gk) and glutamylphosphate reductase (gpr) enzyme complex which catalyzes the first and second steps of proline biosynthesis in e. coli. the first gene of the operon, prob, is predicted ... | 2001 | 11375165 |
| elucidation of listeria monocytogenes contamination routes in cold-smoked salmon processing plants detected by dna-based typing methods. | the contamination routes of listeria monocytogenes in cold-smoked salmon processing plants were investigated by analyzing 3,585 samples from products (produced in 1995, 1996, 1998, and 1999) and processing environments (samples obtained in 1998 and 1999) of two danish smokehouses. the level of product contamination in plant i varied from 31 to 85%, and no l. monocytogenes was found on raw fish (30 fish were sampled). in plant ii, the levels of both raw fish and product contamination varied from ... | 2001 | 11375167 |
| analysis of the role of opuc, an osmolyte transport system, in salt tolerance and virulence potential of listeria monocytogenes. | the success of listeria monocytogenes as a food-borne pathogen owes much to its ability to survive a variety of stresses, both in the external environment prior to ingestion and subsequently within the animal host. growth at high salt concentrations and low temperatures is attributed mainly to the accumulation of organic solutes such as glycine betaine and carnitine. we utilized a novel system for generating chromosomal mutations (based on a lactococcal pwvo1-derived ori(+) repa(-) vector, pori1 ... | 2001 | 11375182 |
| mechanism of actin-based motility. | spatially controlled polymerization of actin is at the origin of cell motility and is responsible for the formation of cellular protrusions like lamellipodia. the pathogens listeria monocytogenes and shigella flexneri, which undergo actin-based propulsion, are acknowledged models of the leading edge of lamellipodia. actin-based motility of the bacteria or of functionalized microspheres can be reconstituted in vitro from only five pure proteins. movement results from the regulated site-directed t ... | 2001 | 11379633 |