Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| incidence of listeria monocytogenes in cheese produced in rio de janeiro, brazil. | the present study evaluated the incidence of listeria spp. in some brazilian cheeses obtained from retail stores in rio de janeiro, of 103 samples of various types of cheese examined as recommended in the listeria isolation protocol of the health protection branch of canada, 11 (10.68%) were contaminated by listeria monocytogenes, 13 (12.62%) by listeria innocua, 6 (5.83%) by listeria grayi, and 1 (0.97%) by listeria welshimeri. a higher incidence of l. monocytogenes as observed mainly in the ho ... | 1998 | 9708310 |
| listeriosis in pediatric oncology patients. | adult cancer patients are considered to be at an increased risk for listeria monocytogenes infections, but, to the authors' knowledge, little information regarding this infection in the pediatric oncology population has been published. | 1998 | 9708951 |
| interaction of hydrostatic pressure, time and temperature of pressurization and pediocin ach on inactivation of foodborne bacteria. | high hydrostatic pressure, because it can kill microorganisms, is being investigated for potential use as a nonthermal food preservation method. the objective of this study was to determine the hydrostatic pressurization parameters, pressure, time, and temperature, and a bacteriocin that in combination would destroy 7 to 8 log cycles of pathogenic and spoilage bacterial populations. we suspended cells of staphylococcus aureus, listeria monocytogenes, salmonella typhimurium, escherichia coli o157 ... | 1998 | 9709205 |
| microbiological quality of australian beef carcass meat and frozen bulk packed beef. | two studies were undertaken to determine the microbiological of beef carcass meat and frozen boneless bulk packed beef produced in australia. samples were collected from 1,063 beef carcasses and from 929 cartons of frozen boneless bulk packed beef over a period of approximately 12 months. samples were collected from works processing beef carcasses for the australian domestic market and from works targeting export markets. on carcasses processed for export markets, where bacterial counts were obt ... | 1998 | 9709207 |
| duplex (thermotroph-psychrotroph) quadrant plates: convenient, error-avoiding tools for monitoring of haccp-contained food lines and for epidemiological investigations under conditions of military or other constraints. | a set of two "two-tier" (thermotroph-psychrotroph) single quadrant plates (qps) was developed previously to allow convenient enumeration of numbers of colony-forming units of most pertinent pathogenic bacteria or marker bacteria in foods. these include listeria monocytogenes, staphylococcus aureus, bacillus cereus, thermotrophic and psychrotrophic enterobacteriaceae, clostridium spp., and enterococcus spp. as the qps had given excellent results in monitoring samples of marketed food products pot ... | 1998 | 9709209 |
| an efficient sampling technique used to detect four foodborne pathogens on pork and beef carcasses in nine belgian abattoirs. | the method presented in this paper should prove useful in assessing the effectiveness of haccp plans developed in slaughterhouses. samples were collected by swabbing well-defined areas of pork and beef carcasses with sterile gauze. between 160 and 420 half-carcasses were swabbed in each of nine pork or beef slaughterhouses. swabs from five carcasses were placed in the same sterile stomacher bag, constituting a single composite sample. standard or validated analytical methods were used to isolate ... | 1998 | 9709223 |
| growth and survival of listeria monocytogenes in vacuum-packaged ground beef inoculated with lactobacillus alimentarius floracarn l-2. | a culture of the psychotrophic strain floracarn l-2 of lactobacillus alimentarius was added to ground beef (ph 5.4) inoculated with two isolates of listeria monocytogenes able to grow in refrigerated ground beef. the ground beef was vacuum-packaged and stored for 9 weeks at 4 degrees c. populations of inoculated l. monocytogenes initially were 6.3 to 6.4 log10 cfu/g and increased to 7.4 log10 cfu/g in ground beef with no added lactobacilli. addition of l. alimentarius l-2 or its antibiotic-resis ... | 1998 | 9709226 |
| recovery of foodborne microorganisms from potentially lethal radiation damage. | a two-stage recovery protocol was examined for microorganisms following gamma irradiation in phosphate buffer at 0 degrees c. in the first stage, survivors were recovered on basal yeast extract agar and held at various temperatures suboptimal for their growth for 20 h (resuscitation protocol). in the second stage the survivors were incubated for an additional 24 h, but in this case at their optimum temperature for growth. controls consisted of survivors which were not subjected to the resuscitat ... | 1998 | 9709232 |
| heat resistance and fatty acid composition of listeria monocytogenes: effect of ph, acidulant, and growth temperature. | the objective of this study was to determine the influence of ph, acidulant, and growth temperature history on the heat resistance and fatty acid composition of listeria monocytogenes scott a. cells were grown to late exponential phase (od600 = 0.6) at 10, 19, or 37 degrees c in brain heart infusion broth acidified to ph 5.4 or 7 with either acetic or lactic acid. thermal death times at 60 degrees c subsequently were determined by using a submerged-coil heating apparatus. the surviving cell popu ... | 1998 | 9709249 |
| chemical and bacteriological characteristics of pichtogalo chanion cheese and mesophilic starter cultures for its production. | sixty-two samples of pichtogalo chanion cheese traditionally produced in crete, a few (3 to 6) days old, were analyzed for some chemical and bacteriological characteristics. the results of physicochemical analyses were as follows: (1) moisture content 61.63% (standard deviation 4.67); (2) fat in dry matter 54.03% (sd 7.73); (3) protein content 14.23% (sd 1.72); (4) salt content 1.02% (sd 0.38); (5) water activity (aw) 0.990 (sd 0.003); and (6) ph 4.36 (sd 0.25). none of the samples yielded salmo ... | 1998 | 9709250 |
| effect of several decontamination procedures on listeria monocytogenes growing in biofilms. | listeria monocytogenes is a pathogenic bacterium which has been implicated in several foodborne illnesses. this microorganism grows into biofilms attached to the surfaces in food-processing plants, increasing its resistance to antimicrobial agents. the present work was realized to investigate the attachment of l. monocytogenes isolates to glass surfaces and to find a decontamination procedure to remove these bacteria in biofilms. three-day biofilms were prepared by growing l. monocytogenes isola ... | 1998 | 9709259 |
| human macrophages induced in vitro by macrophage colony-stimulating factor are deficient in il-12 production. | il-12 is important for th1 differentiation. myeloid-derived antigen-presenting cells (apc) such as monocytes, macrophages (mphi) and dendritic cells (dc) are believed to be major sources of il-12 in vivo. we have compared il-12 production of fresh monocytes with mphi differentiated in vitro using macrophage colony-stimulating factor (m-csf) or human plasma, and in vitro generated dendritic cells, since these differentiated cell types represent apc at sites of antigen challenge. macrophages stimu ... | 1998 | 9710227 |
| survival of bioluminescent listeria monocytogenes and escherichia coli o157:h7 in soft cheeses. | pasteurized and raw milks that had been inoculated at 10(4) cfu/ml with bioluminescent strains of listeria monocytogenes and escherichia coli o157:h7 were used in the manufacture of camembert and feta cheeses with or without nisin-producing starter culture. survival of both organisms was determined during the manufacture and storage of camembert and feta cheeses at 2 +/- 1 degree c for 65 and 75 d, respectively. bacterial bioluminescence was used as an indicator to enumerate the colonies plated ... | 1998 | 9710748 |
| listeria monocytogenes in the colon in a case of fulminant ulcerative colitis. | a case of ulcerative colitis in which the presence of listeria monocytogenes was confirmed in the resected colon with polymerase chain reaction and subsequent southern blot analysis and immunohistochemistry using antibody against listeria is presented. the patient developed ulcerative colitis at the age of 59 years. prednisolone, 50 mg/day, was given for severe ulcerative colitis. later the disease became fulminating, indicating colectomy 4 months after the onset. multiple sealed colonic perfora ... | 1998 | 9712246 |
| effect of siderophores, catecholamines, and catechol compounds on listeria spp. growth in iron-complexed medium. | almost all bacteria require iron for growth and virulence expression. however, listeria spp. do not produce any siderophore for iron acquisition. representative strains of each of the six species of listeria were examined for their ability to use various compounds as iron suppliers in iron-restricted medium. here we show that l. monocytogenes, l. innocua, l. ivanovii, l. welshimeri, l. seeligeri, and l. grayi were able to use exogenous siderophores and various catechol ligands, including catecho ... | 1998 | 9712730 |
| the contributions of reactive oxygen intermediates and reactive nitrogen intermediates to listericidal mechanisms differ in macrophages activated pre- and postinfection. | the contribution of reactive oxygen intermediates (roi) and reactive nitrogen intermediates (rni) to the killing of listeria monocytogenes by macrophages activated by addition of spleen cells from listeria-immune mice plus specific antigen was examined. when macrophages were infected with l. monocytogenes and then spleen cells were added, there was not as big a difference in listericidal activity between macrophages cultured with normal spleen cells and those cultured with immune spleen cells as ... | 1998 | 9712745 |
| fas (cd95)-dependent cell-mediated immunity to listeria monocytogenes. | two distinct and complementary pathways, one mediated by perforin and the other dependent upon cd95 (fas), effect cell-mediated cytotoxicity. we examined the relative roles of these pathways in host defenses against the intracellular bacterial pathogen listeria monocytogenes by using murine listeriosis as a model system. mice which lacked both perforin and fas (p0l0) were generated, and their responses to primary and secondary listeriosis were compared to those of wild-type (wt), fas-deficient ( ... | 1998 | 9712760 |
| entry of listeria monocytogenes into neurons occurs by cell-to-cell spread: an in vitro study. | listeria monocytogenes is an intracellular pathogen that causes severe central nervous system infection in humans and animals. the ability of this bacterium to penetrate nerve cells was investigated by using rat spinal cell cultures. entry into distinct cell types, i. e., glial cells and neurons, was monitored by a differential immunofluorescence technique with antibodies against cell type-specific markers and the bacterial pathogen. l. monocytogenes was detected predominantly within macrophages ... | 1998 | 9712801 |
| fate of gamma-irradiated listeria monocytogenes during refrigerated storage on raw or cooked turkey breast meat. | the radiation resistance and ability of listeria monocytogenes atcc 7644, 15313, 43256, and 49594 to multiply on irradiated, air-packed, refrigerated raw or cooked turkey breast meat nuggets (ca. 25 g) and ground turkey breast meat was investigated. gamma-radiation d values for l. monocytogenes were significantly different on raw and cooked nuggets, 0.56 +/- 0.03 kgy and 0.69 +/- 0.03 kgy, respectively; but they were not significantly different (p < or = 0.05) on raw and cooked ground turkey mea ... | 1998 | 9713758 |
| listeria monocytogenes-associated acute hepatitis in a liver transplant recipient. | we report a case of listeria monocytogenes bacteriemia with liver involvement mimicking acute viral hepatitis in a liver transplant recipient. the patient presented with fever, jaundice and alanine aminotransferase levels ten times the upper limit of normal. liver biopsy showed signs of acute hepatitis and occasional granulomas. both blood and liver biopsy cultures were positive for listeria monocytogenes. the patient received a 3 week course of ampicillin and gentamicin with clinical and bioche ... | 1998 | 9716234 |
| reduced intracellular activity of antibiotics against listeria monocytogenes in multidrug resistant cells. | multidrug resistance is expressed not only by bacteria, but also by tumor cells and by some normal cells of the body. it enables eukaryotic cells to exclude not only cytostatic drugs but also non-cytostatic antibiotics. this was demonstrated in genetically engineered multidrug resistant (mdr) cells infected with the facultative intracellular bacterium listeria monocytogenes for all macrolide antibiotics tested (azithromycin, clarithromycin, erythromycin, josamycin, roxithromycin and spiramycin). ... | 1998 | 9716288 |
| interactions of the bacterial pathogen listeria monocytogenes with mammalian cells: bacterial factors, cellular ligands, and signaling. | listeria monocytogenes is a food borne pathogen which has the very unique property of crossing three barriers during infection eliciting meningitis, meningo-encephalitis and abortions with a mortality rate of about 30%. indeed, after crossing the intestinal barrier, listeria disseminates via the lymph and the blood, to the brain and/or the placenta after crossing the brain-blood barrier and/or the placental barrier. during disease, this organism infects a variety of tissues and cell types in whi ... | 1998 | 9717257 |
| reduction of caecal listeria monocytogenes in leghorn chicks following treatment with a competitive exclusion culture (preempt) | day-of-hatch leghorn chicks were treated by oral gavage with preempt, a continuous-flow competitive exclusion culture containing broiler caecal bacteria, followed by an oral challenge with listeria monocytogenes, to determine the effects of preempt on l. monocytogenes caecal colonization. increased (p < 0.001) concentrations of caecal propionic acid in control chicks compared with preempt-treated chicks at 3 days of age were indicative of the establishment of the preempt bacteria. caeca from con ... | 1998 | 9717314 |
| macrophages and hepatocytic cells as chemokine producers in murine listeriosis. | the major target organ of systemic infection with the intracellular bacterium listeria monocytogenes is the liver, to where inflammatory leukocytes are rapidly recruited. we determined by reverse transcriptase polymerase chain reaction the early chemokine response in the liver after systemic infection of mice with listeriae, and in parallel compared chemokine release from macrophages and hepatocytic cells in vitro. murine bone marrow-derived macrophages (bmm) grown in fetal calf serum-supplement ... | 1998 | 9717670 |
| successful treatment of murine listeriosis and salmonellosis with levofloxacin. | levofloxacin (l-ofloxacin) is a fluoroquinolone derivative. it is the active substance contained in ofloxacin with a broad spectrum of antibacterial activity against both gram-negative and gram-positive bacteria. in this work we examined the activity of levofloxacin against the facultative intracellular bacteria listeria monocytogenes and salmonella typhimurium in vitro, in tissue culture and in animal models of infection. the minimum inhibitory concentrations (mics) mic90 for salmonella enteric ... | 1998 | 9720471 |
| identification of the gene encoding the alternative sigma factor sigmab from listeria monocytogenes and its role in osmotolerance. | listeria monocytogenes is well known for its robust physiology, which permits growth at low temperatures under conditions of high osmolarity and low ph. although studies have provided insight into the mechanisms used by l. monocytogenes to allay the physiological consequences of these adverse environments, little is known about how these responses are coordinated. in the studies presented here, we have cloned the sigb gene and several rsb genes from l. monocytogenes, encoding homologs of the alt ... | 1998 | 9721294 |
| inhibition of listeria monocytogenes by plantaricin na, an antibacterial substance from lactobacillus plantarum. | a lactobacillus plantarum of vegetable origin produced a bacteriocin inhibitor to listeria monocytogenes. the antimicrobial agent was inactivated by proteolytic enzymes, was resistant to heat (100 degrees c for 30 min) and stable over a wide ph range (ph 2-10), and displayed a bactericidal mode of action. growth inhibition of l. monocytogenes depend on bacteriocin concentration. the antilisterial efficiency depended on the strain of l. monocytogenes used but was not influenced by the growth phas ... | 1998 | 9721606 |
| antibiotic use in neonatal sepsis. | neonatal sepsis is a life-threatening emergency and any delay in treatment may cause death. initial signs of neonatal sepsis are slight and nonspecific. therefore, in suspected sepsis, two or three days empirical antibiotic therapy should begin immediately after cultures have been obtained without awaiting the results. antibiotics should be reevaluated when the results of the cultures and susceptibility tests are available. if the cultures are negative and the clinical findings are well, antibio ... | 1998 | 9722468 |
| listeria monocytogenes as a probe to study cell-mediated immunity. | the intracellular bacterium listeria monocytogenes continues to serve as a model to define general paradigms of cell-mediated immunity. genetic manipulations of the bacterium and its murine host have allowed us to begin dissecting the intricate interactions between this bacterium and the immune system. as a result, we have gained new insights into the mechanisms of immune surveillance, achieved better understanding of bacterial tactics for immune evasion and developed novel strategies in vaccine ... | 1998 | 9722922 |
| minimum inhibitory concentration of smoke wood extracts against spoilage and pathogenic micro-organisms associated with foods. | antimicrobial activity of seven commercial smoke preparations (four liquid and three solid) was studied. the minimum inhibitory concentration (mic) was determined against a selection of food spoilage and pathogenic micro-organisms. the main smoke components were identified and quantified by gas chromatography/mass spectrometry. the most effective condensate was s2. all strains except salmonella enteritidis were inhibited by s2 with an mic < 0.5-1.5%. smoke extract l2 inhibited growth of vibrio v ... | 1998 | 9722997 |
| th1 cells specific for a secreted protein of listeria monocytogenes are protective in vivo. | in the present study we have investigated the role of the secreted p60 protein from listeria monocytogenes as an ag for cd4 t cells. the p60 protein is an abundant extracellular protein that is highly conserved within the members of the genus listeria. our results show that l. monocytogenes infection induces a potent p60-specific th1 immune response. remarkably, we found that p60-specific th1 clones mediate significant protection against l. monocytogenes infection. for one p60-specific clone, th ... | 1998 | 9637521 |
| il-6 produced by kupffer cells induces stat protein activation in hepatocytes early during the course of systemic listerial infections. | kupffer cells were the principal source of il-6 produced in the livers of mice following i.v. inoculation of listeria monocytogenes. il-6 mrna expression and the production of il-6 were reduced drastically within the nonparenchymal liver cell population derived from mice rendered kupffer cell depleted by pretreatment with liposome-encapsulated dichloromethylene diphosphonate. a sharp increase in the appearance of activated stat3 occurred in extracts of purified hepatocytes derived from normal mi ... | 1998 | 9637522 |
| altered intestinal immune system but normal antibacterial resistance in the absence of p-selectin and icam-1. | icam-1 and p-selectin are adhesion molecules that regulate leukocyte migration, extravasation to inflammatory sites, and other immune cell interactions. t cell-mediated resistance against acute infection with listeria monocytogenes and chronic infection with mycobacterium bovis calmette-guérin bacillus was investigated in mutant mice lacking p-selectin and/or icam-1. mice deficient in p-selectin (psel-/-), icam-1 (icam-/-), or the combination of both (psel-/- x icam-/-) showed normal bacterial c ... | 1998 | 9637528 |
| [a case of listeria monocytogenes sepsis in an elderly who survived]. | a 81-year-old man who complained of fever and disturbance of consciousness was admitted to our hospital. listeria monocytogenes type 1/2aa was cultured from only the blood. he was treated with gamma-globrine and sensitive antibiotics (papm/bp, em) immediately after admission, and recovered in spite of multiple organ failure due to septic shock. he was not an immunocompromised host and did not have complication of meningitis, but had rhabdomyolysis and liver dysfunction. | 1998 | 9642946 |
| attenuated listeria monocytogenes carrier strains can deliver an hiv-1 gp120 t helper epitope to mhc class ii-restricted human cd4+ t cells. | listeria monocytogenes is a facultative intracellular pathogen which, following uptake by macrophages, escapes from the phagosome and replicates in the cytoplasm. this property has been exploited using recombinant l. monocytogenes as a carrier for the intracytoplasmic expression of antigens when mhc class i-restricted cytotoxic t lymphocyte responses are required. much less is known of the ability of these bacteria to trigger mhc class ii-restricted responses. here, we demonstrate that after ing ... | 1998 | 9645361 |
| [comment on the letter to the editor: "acute hydrocephalus and cerebral abscess in meningitis due to listeria monocytogenes"]. | 1998 | 9646634 | |
| interaction of human arp2/3 complex and the listeria monocytogenes acta protein in actin filament nucleation. | actin filament assembly at the cell surface of the pathogenic bacterium listeria monocytogenes requires the bacterial acta surface protein and the host cell arp2/3 complex. purified arp2/3 complex accelerated the nucleation of actin polymerization in vitro, but pure acta had no effect. however, when combined, the arp2/3 complex and acta synergistically stimulated the nucleation of actin filaments. this mechanism of activating the host arp2/3 complex at the l. monocytogenes surface may be similar ... | 1998 | 9651243 |
| evolution of a complex t cell receptor repertoire during primary and recall bacterial infection. | the mechanisms underlying the genesis and maintenance of t cell memory remain unclear. in this study, we examined the evolution of a complex, antigen-specific t cell population during the transition from primary effector to memory t cells after listeria monocytogenes infection. t cell populations specific for listeriolysin o (llo)91-99, the immunodominant epitope recognized by h2-kd-restricted t lymphocytes, were directly identified in immune spleens using tetrameric h2-kd-epitope complexes. the ... | 1998 | 9653084 |
| targeted disruption of the interferon-gamma receptor 2 gene results in severe immune defects in mice. | to study the role of the interferon- (ifn) gammar2 chain in ifn-gamma signaling and immune function, ifn-gammar2-deficient mice have been generated and characterized. cells derived from ifn-gammar2 -/- mice are unable to activate either jak/stat signaling proteins or gene transcription in response to ifn-gamma. the lack of ifn-gamma responsiveness alters ifn-gamma-induced ig class switching by b cells from these mice. in vitro cultures of t cells demonstrate that the t cells from the ifn-gammar2 ... | 1998 | 9653170 |
| listeria monocytogenes and serratia marcescens infections as models for th1/th2 immunity in laboratory cats. | five species of bacteria known to be naturally-occurring pathogens of cats were screened for their ability to grow in feline macrophages in vitro, and to induce antibodies and delayed type hypersensitivity (dth) responses in vivo. two of these organisms, l. monocytogenes and s. marcescens, were selected for further study based on clear-cut differences in their in vitro and in vivo behavior. listeria was macrophage tropic, induced dth, and evoked poor antibody responses post-recovery, whereas ser ... | 1998 | 9656444 |
| general stress transcription factor sigmab and its role in acid tolerance and virulence of listeria monocytogenes. | the gene encoding the general stress transcription factor sigmab in the gram-positive bacterium listeria monocytogenes was isolated with degenerate pcr primers followed by inverse pcr amplification. evidence for gene identification includes the following: (i) phylogenetic analyses of reported amino acid sequences for sigmab and the closely related sigmaf proteins grouped l. monocytogenes sigmab in the same cluster with the sigmab proteins from bacillus subtilis and staphylococcus aureus, (ii) th ... | 1998 | 9658010 |
| effect of in vitro monocyte activation by listeria monocytogenes antigens on phagocytosis and production of reactive oxygen and nitrogen radicals in bovines. | macrophages by virtue of their phagocytic and antibacterial activities play an important role in the host resistance to intracellular pathogens including listeria monocytogenes. however, the precise killing mechanism adopted by macrophages in the case of l. monocytogenes and the role of macrophage activation in bacterial killing are still unclear. in the present investigation, different antigens of pathogenic l. monocytogenes and three non-specific activators, namely, lipopoly-saccharide (lps), ... | 1998 | 9661264 |
| diagnosis of meningococcal meningitis by broad-range bacterial pcr with cerebrospinal fluid. | we used broad-range bacterial pcr combined with dna sequencing to examine prospectively cerebrospinal fluid (csf) samples from patients with suspected meningitis. fifty-six csf samples from 46 patients were studied during the year 1995. genes coding for bacterial 16s and/or 23s rrna genes could be amplified from the csf samples from five patients with a clinical picture consistent with acute bacterial meningitis. for these patients, the sequenced pcr product shared 98.3 to 100% homology with the ... | 1998 | 9665992 |
| interactions of listeria monocytogenes with mammalian cells during entry and actin-based movement: bacterial factors, cellular ligands and signaling. | although <50 kb of its 3.3 megabase genome is known, listeria monocytogenes has received much attention and an impressive amount of data has contributed in raising this bacterium among the best understood intracellular pathogens. the mechanisms that listeria uses to enter cells, escape from the phagocytic vacuole and spread from one cell to another using an actin-based motility process have been analysed in detail. several bacterial proteins contributing to these events have been identified, inc ... | 1998 | 9669997 |
| disseminated herpes simplex virus infection in a neonate. | the emergency department (ed) evaluation of the neonate with sepsis or symptoms suggesting sepsis usually includes a complete blood count, catheterized urinalysis with culture, blood cultures, cerebrospinal fluid analysis and culture, and possibly a chest radiograph. admission for observation for neonates at high risk for sepsis is universal. depending on the patient's presentation and the preference of the admitting physician, intravenous antibiotics are started. typically, ampicillin and eithe ... | 1998 | 9672455 |
| pathogenicity and immunogenicity of a listeria monocytogenes strain that requires d-alanine for growth. | listeria monocytogenes is an intracellular bacterial pathogen that elicits a strong cellular immune response following infection and therefore has potential use as a vaccine vector. however, while infections by l. monocytogenes are fairly rare and can readily be controlled by a number of antibiotics, the organism can nevertheless cause meningitis and death, particularly in immunocompromised or pregnant patients. we therefore have endeavored to isolate a highly attenuated strain of this organism ... | 1998 | 9673233 |
| the role of protegrins and other elastase-activated polypeptides in the bactericidal properties of porcine inflammatory fluids. | the mammalian host response to infection includes the production and secretion of antimicrobial peptides from phagocytes and epithelial cells. protegrins, a group of broadly microbicidal peptides isolated originally from porcine neutrophil lysates, were found to be stored as inactive proforms in porcine neutrophil granules but could be activated extracellularly by neutrophil elastase. we assessed the biological role of protegrins and other elastase-activated polypeptides in the microbicidal acti ... | 1998 | 9673240 |
| regulation of hly expression in listeria monocytogenes by carbon sources and ph occurs through separate mechanisms mediated by prfa. | expression of the prfa-controlled virulence gene hly (encoding the pore-forming cytolysin listeriolysin) is under negative regulation by readily metabolized carbon sources in listeria monocytogenes. however, the hyperhemolytic strain nctc 7973 exhibits deregulated hly expression in the presence of repressing sugars, raising the possibility that a defect in carbon source regulation is responsible for its anomalous behavior. we show here that the activity of a second glucose-repressed enzyme, alph ... | 1998 | 9673243 |
| listeria monocytogenes stimulates mucus exocytosis in cultured human polarized mucosecreting intestinal cells through action of listeriolysin o. | when the intracellular pathogen listeria monocytogenes infects cultured human mucosecreting polarized ht29-mtx cells apically, it induces the stimulation of mucus exocytosis without cell entry. using a set of isogenic mutants and purified listeriolysin o (llo), we identified the l. monocytogenes thiol-activated exotoxin llo as the agonist of mucus secretion. we demonstrated that the llo-induced mucus exocytosis did not result from the llo membrane-damaging activity. we found that llo-induced muc ... | 1998 | 9673248 |
| interactions of the invasive pathogens salmonella typhimurium, listeria monocytogenes, and shigella flexneri with m cells and murine peyer's patches. | invasive enteric bacteria must pass through the intestinal epithelium in order to establish infection. it is becoming clear that a common target for intestinal mucosa penetration is the specialized epithelial cell of peyer's patches, the m cell. in order to gain a better understanding of how bacteria interact with m cells, we have compared the interactions of salmonella typhimurium, listeria monocytogenes, and shigella flexneri with m cells by using a murine ligated-loop model. our results indic ... | 1998 | 9673259 |
| gelsolin, a protein that caps the barbed ends and severs actin filaments, enhances the actin-based motility of listeria monocytogenes in host cells. | the actin-based motility of listeria monocytogenes requires the addition of actin monomers to the barbed or plus ends of actin filaments. immunofluorescence micrographs have demonstrated that gelsolin, a protein that both caps barbed ends and severs actin filaments, is concentrated directly behind motile bacteria at the junction between the actin filament rocket tail and the bacterium. in contrast, capg, a protein that strictly caps actin filaments, fails to localize near intracellular listeria. ... | 1998 | 9673261 |
| molecular typing of listeria monocytogenes isolated in japan by pulsed-field gel electrophoresis. | a total of 40 strains of listeria monocytogenes which have been demonstrated to be serovar 1/2a, 1/2b, and 4b were genotyped by pulsed-field gel electrophoresis (pfge) after separate digestion with apa i, asc i, sma i, and sse 8387 i. twenty-seven unrelated strains including four representative strains showed distinctly different genotypes according to their pfge profiles. then nine strains isolated from shredded cheese of different lots and four strains isolated from the cheese-processing envir ... | 1998 | 9673950 |
| bacteriocin inhibition of two glucose transport systems in listeria monocytogenes. | listeria monocytogenes transports glucose by proton motive force-mediated and phosphoenolpyruvate-dependent phosphotransferase systems (pep-dependent pts). inhibition of both systems by nisin, pediocin jd and leuconosin s is reported here for four strains of l. monocytogenes. intracellular and extracellular adenosine triphosphate (atp) and extracellular inorganic phosphate were measured in energized l. monocytogenes scott a cells to determine whether inhibition of the pep-dependent pts might occ ... | 1998 | 9674123 |
| effect of oxygen concentration and redox potential on recovery of sublethally heat-damaged cells of escherichia coli o157:h7, salmonella enteritidis and listeria monocytogenes. | the measured heat resistance of cells of escherichia coli o157:h7, salmonella enteritidis and listeria monocytogenes was up to eightfold greater when they were grown, heated and recovered anaerobically rather than aerobically. measured heat resistance was highest when anaerobic gas mixtures were used (time at 59 degrees c for a 6-decimal (6-d) reduction of e. coli o157:h7, 19-24 min); moderate when low concentrations of oxygen (0.5-1%) were included (time for a 6-d reduction, 5-17 min); and lowe ... | 1998 | 9674145 |
| reducing total aerobic counts and listeria monocytogenes on the surface of king salmon (oncorhynchus tshawytscha). | a trial industrial-scale fin-fish washing system was assessed for its effectiveness in removing bacteria associated with the skin of gilled and gutted king salmon (oncorhynchus tshawytscha). exposure of the salmon to 200 ppm free chlorine at a turnover rate for the total volume of the wash solution of 2.25 cycles h-1 for 120 min resulted in decreases in the aerobic plate count (apc) recovered from the salmon ranging from 96.6 to 99.2%. in order to optimize the washing regime a laboratory-scale f ... | 1998 | 9678168 |
| heat stability of virulence-associated enzymes from listeria monocytogenes slcc 5764. | the enzyme activities of listeriolysin o (llo), phosphatidylinositol-specific phospholipase c (pi-plc), catalase (ca), and superoxide dismutase (sod) from listeria monocytogenes slcc 5764 were examined after heat treatment, growth at elevated temperatures, and anaerobic growth. growth at elevated temperatures may influence virulence as expressed by virulence enzyme activity. the enzymes were heated for 0 and 10 min at temperatures ranging from 40 to 100 degrees c. the production of llo was exami ... | 1998 | 9678177 |
| differential chemokine response of murine macrophages stimulated with cytokines and infected with listeria monocytogenes. | during inflammatory processes the infected macrophage is a rich source of chemokines which induce infiltration of leukocytes to the site of infection. we investigated the regulation of chemokine production by murine macrophages in response to infection with the intracellular bacterial pathogen, listeria monocytogenes. as a source of quiescent macrophages, murine bone marrow-derived macrophages (bmm) cultured under serum-free conditions were used. with rt-pcr, we detected induction of rna message ... | 1998 | 9678756 |
| listeriolysin o: cholesterol inhibits cytolysis but not binding to cellular membranes. | listeriolysin o (llo) binds to cholesterol-containing membranes in which it oligomerizes to form pores. preincubation of the toxin with cholesterol is known to inhibit haemolysis, whereas the oxidized form of cholesterol has no inhibitory effect. using immunoblot analyses and flow cytometry we demonstrate that preincubation with cholesterol does not influence binding of the listeriolysin-cholesterol complex to red blood cells, eukaryotic cells or artificial membranes. lytic activity of membrane- ... | 1998 | 9680200 |
| specificity of the bax polymerase chain reaction system for detection of the foodborne pathogen listeria monocytogenes. | the polymerase chain reaction (pcr) can be used for rapid and specific detection of foodborne pathogens. one commercial kit, the qualicon bax system uses pcr to detect listeria monocytogenes in enrichment cultures derived from food and environmental samples. the specificity and sensitivity of the bax system for detecting l. monocytogenes were characterized by using both pure and mixed cell cultures, and optimal conditions for production of cell lysates were determined. the bax system was highly ... | 1998 | 9680707 |
| control of il-12 and ifn-gamma production in response to live or dead bacteria by tnf and other factors. | when mice were infected i.v. with either listeria monocytogenes or brucella abortus, bioactive il-12 was briefly detected in serum and supernatants of spleen homogenates immediately ex vivo. although the time scale was more prolonged for the more slowly growing b. abortus, in both instances il-12 production ceased while bacteria still persisted in high numbers. production of il-12, detected in serum and spleen, was neither increased nor prolonged by injecting abs to il-10 or il-4. in contrast wi ... | 1998 | 9686610 |
| unstable expression and thermal instability of a species-specific cell surface epitope associated with a 66-kilodalton antigen recognized by monoclonal antibody em-7g1 within serotypes of listeria monocytogenes grown in nonselective and selective broths. | conditions that resulted in unstable expression and heat instability of a cell surface epitope associated with a 66-kda antigen in listeria monocytogenes serotypes were identified with the probe monoclonal antibody (mab) em-7g1 in an enzyme-linked immunosorbent assay. this epitope appeared to be absent in three serotypes (serotypes 3b, 4a, and 4c), which did not react with mab em-7g1 irrespective of the enrichment broth tested. the remaining 10 serotypes were detected by mab em-7g1 only when cel ... | 1998 | 9687476 |
| [the roles of heat shock proteins in host defense against bacterial infection]. | heat shock proteins (hsp) are widely distributed in nature, and are highly conserved proteins among prokaryotes and eukaryotes. these proteins are known to be involved in cytoprotection against various stress conditions including bacterial infection, and immune responses to various pathogens such as bacteria. in this study, we showed that hsp70 protected macrophages infected with salmonella choleraesuis against tnf-alpha-induced cell death. furthermore, hsp70-reactive cd4+ t cells appeared durin ... | 1998 | 9691765 |
| perinephric abscess (presenting as abdominal pain) due to listeria monocytogenes. | a 5-year-old malnourished child was admitted with a 1-week history of paroxysmal abdominal pain. evaluation finally revealed a left-sided perinephric abscess caused by listeria monocytogenes. the child was successfully treated by drainage of the abscess and antibiotic therapy. renal abscess should be kept in mind in the differential diagnosis of abdominal pain, and listeria, an unusual pathogen, should be considered as a possible aetiology. | 1998 | 9692004 |
| septic arthritis with listeria monocytogenes during low-dose methotrexate. | we describe a 22-year-old female with systemic lupus erythematosus and lymphopenia, who developed septic arthritis of the right knee with listeria monocytogenes type 1/2 a, whilst on low-dose methotrexate (mtx). so far, septic arthritis due to this microorganism has been reported in two other patients treated with low-dose mtx, one having rheumatoid arthritis and the other psoriatic arthritis. no reports exist on patients treated with other cytotoxic antirheumatic therapies. | 1998 | 9698030 |
| effects of ph or a(w) stress on growth of listeria monocytogenes. | the growth of three strains of listeria monocytogenes at 20 degrees c in a meat broth of different ph or water activity was investigated. at inoculation or at the beginning of the exponential phase, cells were exposed to stress by the addition of naoh or nh4+, acetic acid, nacl or kcl, in order to reach a ph of either 9.0 or 5.6, or an a(w) of 0.950 or 0.965, respectively. the effects of the exposure to stress on the generation and lag times of each strain were analysed by turbidity measurements ... | 1998 | 9706800 |
| inhibition of listeria monocytogenes in a pork product by a lactobacillus sake strain. | a lactobacillus sake strain (l. sake 2a), isolated from brazilian sausage ('lingüiça'), possessed antilisterial activity. the inhibitory activity observed in culture media was due to a proteinaceous compound, as demonstrated by the sensitivity to proteolytic enzymes. inhibition due to hydrogen peroxide, organic acids and lytic bacteriophages was ruled out. the inhibition of listeria monocytogenes by l. sake 2a was also demonstrated in laboratory-prepared 'lingüiça'. after four weeks at 8 degrees ... | 1998 | 9706804 |
| prevalence and growth of listeria monocytogenes in naturally contaminated seafood. | listeria monocytogenes contamination of seafood varies with product category. the highest prevalence was found in cold-smoked fish (34-60%), while the lowest was found in heat-treated and cured seafood (4-12%). the prevalence of l. monocytogenes differed greatly in cold-smoked salmon between production sites, ranging from < 1.4% (nil out of 70 samples) to 100%. the prevalence at the individual production sites was reproducible at repeated sampling. the results indicate that it is possible to pro ... | 1998 | 9706805 |
| reactivities of genus-specific monoclonal antibody em-6e11 against listeria species and serotypes of listeria monocytogenes grown in nonselective and selective enrichment broth media. | depending on the growth medium used for enrichment of bacterial cells prior to assay, the monoclonal antibody (mab) em-6e11 recognizing listeria genus-specific epitope on 43 and 94 to 97 kda cell-surface antigens (a. k. bhunia and m. g. johnson, appl. environ. microbiol. 58:1924-1929, 1992) exhibited extensive variability in the detection of listeria species. mab em-6e11 strongly detected live cells of all listeria species and all serotypes of l. monocytogenes by elisa when cells were grown in n ... | 1998 | 9766076 |
| identification of listeria monocytogenes from unpasteurized apple juice using rapid test kits. | a microbiological survey of 50 retail juices was conducted in the fall of 1996. these juices were analyzed for listeria monocytogenes, escherichia coli o157:h7, salmonella, coliforms, fecal coliforms, and ph. two unpasteurized juices were positive for l. monocytogenes: an apple juice and an apple raspberry blend with a ph of 3.78 and 3.75, respectively. three l. monocytogenes isolates were characterized. the colonies were typical for listeria sp. on oxford and lithium chloride-phenylethanol-moxa ... | 1998 | 9766077 |
| inactivation of listeria monocytogenes in milk by pulsed electric field. | pasteurized whole, 2%, and skim milk were inoculated with listeria monocytogenes scott a and treated with high-voltage pulsed electric field (pef). the effects of milk composition (fat content) and pef parameters (electric field strength, treatment time, and treatment temperature) on the inactivation of the bacterium were studied. no significant differences were observed in the inactivation of l. monocytogenes scott a in three types of milk by pef treatment. with treatment at 25 degrees c, 1- to ... | 1998 | 9766078 |
| listeria infection after liver transplantation: report of a case and review of the literature. | listeria monocytogenes is a well-recognized cause of bacteremia and meningitis in immunocompromised individuals, including recipients of solid organ transplants, but has only rarely been reported following orthotopic liver transplantation (olt). most previously reported cases of listeriosis occurred months to years following liver transplantation; we describe a case of listeriosis that occurred within 1 wk of liver transplantation, shortly after discontinuation of trimethoprim-sulfamethoxazole p ... | 1998 | 9772060 |
| effects of prolonged exposure to morphine and methadone on in vivo parameters of immune function in rats. | in rats, two 6-week repeated dose oral toxicity studies were performed with morphine (250 and 500 mg/kg food) and methadone (200 and 400 mg/kg food), respectively. alterations in immune function were studied by assessing primary and secondary immune responses to sheep red blood cells. in addition, the ability to resist challenge with infectious agents was measured in host resistance models employing the parasite trichinella spiralis and the bacterium listeria monocytogenes. the primary and secon ... | 1998 | 9772098 |
| central nervous system infection with listeria monocytogenes. 33 years' experience at a general hospital and review of 776 episodes from the literature. | we reviewed 776 previously reported and 44 new cases of cns listeriosis outside of pregnancy and the neonatal period, and evaluated the epidemiologic, diagnostic, and therapeutic characteristics of this infection. among patients with listeria meningitis/meningoencephalitis, hematologic malignancy and kidney transplantation were the leading predisposing factors, but 36% of patients had no underlying diseases recognized. the infection occurred throughout life, with a higher incidence before the ag ... | 1998 | 9772921 |
| [listeria monocytogenes: a rare cause of spontaneous bacterial peritonitis in liver cirrhosis]. | 1998 | 9775176 | |
| bone marrow cellular composition in listeria monocytogenes infected mice detected using er-mp12 and er-mp20 antibodies: a flow cytometric alternative to differential counting. | detailed assessment of bone marrow cellular composition is essential in the evaluation of various experimental in vivo systems, such as expression of transgenes, null mutations and stimulation of host defence in infection. traditional morphological analysis of mouse bone marrow is laborious, requires specific cytological expertise, and is somewhat subjective. as an alternative, we have examined whether double labelling of bone marrow with the anti-precursor monoclonal antibodies er-mp12 and er-m ... | 1998 | 9776572 |
| studying m cells and their role in infection. | in addition to sampling antigens, m cells are a common route for pathogen invasion. recent studies have partly defined the mechanisms by which pathogens interact with and exploit m cells as a gateway into the host. new research tools are facilitating studies on m cell infection, differentiation and function. | 1998 | 9778729 |
| heat-killed listeria monocytogenes as an adjuvant converts established murine th2-dominated immune responses into th1-dominated responses. | we investigated the capacity of heat-killed listeria monocytogenes (hkl), a potent stimulator of the innate immune system, as a vaccine adjuvant to modify both primary and secondary ag-specific immune responses. mice immunized with the ag keyhole limpet hemocyanin (klh) mixed with hkl generated a klh-specific primary response characterized by production of th1 cytokines and large quantities of klh-specific igg2a ab. moreover, administration of klh with hkl as an adjuvant reversed established imm ... | 1998 | 9780187 |
| use of the protective antigen of erysipelothrix rhusiopathiae in the enzyme-linked immunosorbent assay and latex agglutination. | to establish a safe and convenient serodiagnostic method for swine erysipelas, a purified protective protein antigen of erysipelothrix rhusiopathiae, which included a large amount of protective protein (64 kda protein), was used for enzyme-linked immunosorbent assay (elisa) and the latex agglutination (la) test. in the elisa, the antisera to four different serovars (1a, 2, 5 and 20) of e. rhusiopathiae exhibit a positive reaction, while antisera to other species of bacteria (listeria monocytogen ... | 1998 | 9780828 |
| [newborn infant bacterial infections. diagnosis, treatment principles, prevention]. | 1998 | 9781160 | |
| [the persistent characteristics of listeria monocytogenes isolated from different sources]. | a number of biological properties of l. monocytogenes was studied. significant differences in the lysozyme, "anti-interferon", rnaase and lipase activity between strains isolated from different warm-blooded animals and from environmental objects were shown. 75% of all strains under study were found to have "anti-interferon" activity, while no antilysozyme activity was detected. | 1998 | 9783394 |
| interaction of listeria monocytogenes with human brain microvascular endothelial cells: inlb-dependent invasion, long-term intracellular growth, and spread from macrophages to endothelial cells. | invasion of endothelial tissues may be crucial in a listeria monocytogenes infection leading to meningitis and/or encephalitis. internalization of l. monocytogenes into endothelial cells has been previously demonstrated by using human umbilical vein endothelial cells as a model system. however, during the crossing of the blood-brain barrier, l. monocytogenes most likely encounters brain microvascular endothelial cells which are strikingly different from macrovascular or umbilical vein endothelia ... | 1998 | 9784531 |
| immunohistochemical detection of listeria antigens in the placenta in perinatal listeriosis. | listeria monocytogenes, a worldwide pathogen, causes significant perinatal mortality and morbidity and has been implicated in spontaneous abortions, still-births, premature delivery, and neonatal sepsis, often with meningitis. maternal symptoms are frequently minimal, and diagnosis is made only if the suspicion is high and diagnostic maternal blood or amniotic fluid cultures are performed. because cultures are not routinely performed on spontaneously aborted fetuses, many authors feel that the t ... | 1998 | 9785135 |
| in-vitro activity of the new ketolide antibiotic hmr 3647 against gram-positive bacteria. | the comparative in-vitro activity of hmr 3647, a new ketolide antibiotic, was investigated against 492 clinical isolates of gram-positive bacteria, including multiply resistant strains, by an agar-dilution technique. all streptococci tested were inhibited by the new ketolide at concentrations < or = 0.5 mg/l. hmr 3647 was more potent than erythromycin against staphylococci. for enterococci the new compound yielded an mic90 of 8 mg/l. erysipelothrix spp., pediococcus spp., leuconostoc spp., lacto ... | 1998 | 9786468 |
| detection of listeria in raw and pasteurized milk. | one hundred raw milk samples from different regions of anatolia and 20 pasteurized milk samples from three different manufacturers in ankara were analyzed for the presence of listeria spp. l. monocytogenes was found in 1% of the raw milk samples and in 5% (1/20) of the pasteurized milk samples. l. innocua and l. seeligeri were found in 8 and 2% of the raw milk samples, respectively. no other species of listeria was found. the overall incidence of listeria spp. was 10% in the raw milk samples and ... | 1998 | 9787931 |
| perinatal listeriosis: a population-based multicenter study in barcelona, spain (1990-1996). | the aim off this study was to describe the incidence, epidemiology, clinical presentation, and outcome of perinatal listeriosis for a 7-year period (1990-1996) based on data of an active population-based surveillance project implemented in the city of barcelona, spain. there were 30 cases (20.8%) associated with pregnancy (15 pregnant women, 13 neonates, and 2 fetal deaths). the incidence of perinatal listeriosis varied from 4.1 to 0 per 10,000 live births. the proportion of perinatal cases in r ... | 1998 | 9788644 |
| occurrence of listeria monocytogenes in sewage sludge. | the search for salmonella is the only bacteriological index included in italian guidelines (in accordance with eu regulations) for the use of sewage sludge in agriculture. as a result, information regarding the presence of listeria monocytogenes is rather limited. we therefore decided to carry out an investigation of listeria in the sludge produced by the bologna (italy) treatment plant during the various phases of treatment. five different types of sludge were analysed (primary raw, activated, ... | 1998 | 9789361 |
| a novel prfa-regulated chromosomal locus, which is specific for listeria ivanovii, encodes two small, secreted internalins and contributes to virulence in mice. | several large, cell wall-associated internalins and one small, secreted internalin (inlc) have been described previously in listeria monocytogenes. using degenerate primers derived from sequenced peptides of an l. ivanovii major secreted protein, we identified a new 4.25 kb internalin locus of l. ivanovii, termed i-inlfe. the two proteins encoded by this locus, i-inle and i-inlf, belong to the group of small, secreted internalins. southern blot analyses show that the i-inlfe locus does not occur ... | 1998 | 9791184 |
| [infectious aneurysm due to listeria monocytogenes: a new case and review of the literature]. | infections due to listeria monocytogenes usually occur in pregnant women, in the elderly and in immunocompromised patients. arterial aneurysms due to this germ are rare. only 16 cases have been previously described in the literature. | 1998 | 9793154 |
| the effect of reuterin on listeria monocytogenes and escherichia coli o157:h7 in milk and cottage cheese. | a broad-spectrum reuterin produced during anaerobic fermentation of glycerol by lactobacillus reuteri strain 12002 was found to be inhibitory and bactericidal for listeria monocytogenes and escherichia coli o157:h7. lyophilized reuterin was prepared by a two-step fermentation process. a batch fermentation in a 15-liter fermentor was applied to produce a maximum biomass of l. reuteri using a modified mrs broth at ph 4.3. further, harvested cells were used to ferment glycerol (250 mm) under anaero ... | 1998 | 9798141 |
| antimicrobial effects of d-3-phenyllactic acid on listeria monocytogenes in tsb-ye medium, milk, and cheese. | d-3-phenyllactic acid is a compound with anti-listeria activity which is produced and secreted by the yeastlike fungus, geotrichum candidum. this compound has a bactericidal effect independent of the physiological state of listeria monocytogenes when added at a concentration of 7 mg/ml to tryptic soy broth supplemented with yeast extract (tsb-ye). an initial l. monocytogenes population of 10(5) cfu/ml was reduced 100-fold (2 log) after 4 days of culture at 25 degrees c in tsb-ye containing d-3-p ... | 1998 | 9798142 |
| influence of environmental stress on the kinetics and strength of attachment of listeria monocytogenes scott a to buna-n rubber and stainless steel. | attachment and detachment of listeria monocytogenes scott a to buna-n rubber and stainless steel under varying conditions of temperature and ph were investigated using model systems. numbers of attached cells increased with increasing attachment temperature (10 to 45 degrees c) and time (up to 120 min) for both test surfaces. compared to buna-n rubber, the rate of attachment to stainless steel was markedly more rapid for all temperature and ph conditions studied and could not be calculated. rate ... | 1998 | 9798143 |
| effect of environmental stress on the ability of listeria monocytogenes scott a to attach to food contact surfaces. | attachment of listeria monocytogenes scott a to buna-n rubber and stainless steel under different temperature and ph conditions at the time of cell growth or at the time of attachment was investigated. all experiments were conducted using sterile phosphate buffer to avoid cell growth during exposure to the test surfaces. numbers of attached cells increased with increasing attachment temperature (10 to 45 degrees c) and exposure time for both test surfaces. maximum levels of attached cells were o ... | 1998 | 9798144 |
| the contamination of pâté with listeria monocytogenes--results from the 1994 european community-coordinated food control program for england and wales. | the listeria monocytogenes contamination of 3,065 pâté products sampled at the point of retail sale in england and wales was examined. ninety-seven percent of samples were free of contamination with l. monocytogenes, 2.0% (60) had levels of less than 200 cfu/g, and 0.6% (18) had levels of 200 cfu/g or more. fish and seafood pâté were significantly more commonly contaminated by l. monocytogenes than other pâté types (chi 2 test, p = 0.001). pâté obtained from small retail shops was significantly ... | 1998 | 9798145 |
| efficacy of spray application of chlorinated water in killing pathogenic bacteria on raw apples, tomatoes, and lettuce. | washing whole and cut produce by dipping or submerging in chlorinated water has a sanitizing effect, although reduction in microbial populations is minimal and is usually less than 100-fold. a study was undertaken to evaluate the efficacy of a spray application of chlorine in killing salmonella, escherichia coli o157:h7, listeria monocytogenes, yeasts and molds, and total aerobic mesophilic microorganisms on whole apples, tomatoes, and lettuce leaves. inoculated produce was treated (sprayed and ... | 1998 | 9798146 |
| antibiotic resistance of salmonella spp. and listeria spp. isolates from traditionally made fresh sausages in greece. | sixty-five samples of traditionally made fresh sausages obtained from retail shops and butcher shops in northern greece were screened for the presence of salmonella spp. and listeria spp. salmonella spp. were found in 20% of the samples tested (54% salmonella typhimurium and 46% salmonella enteritidis). the prevalence of listeria spp. in the samples was 26% (12% listeria monocytogenes, 76% listeria innocua, and 12% listeria welshimeri). nine of 13 salmonella isolates were found to be resistant t ... | 1998 | 9798159 |
| susceptibility of antibiotic-resistant and antibiotic-sensitive foodborne pathogens to acid anionic sanitizers. | acid anionic sanitizers for treatment of fruits and vegetables were prepared using ingredients generally recognized as safe by the u.s. food and drug administration or anionic surfactants and organic acid food additives. they met the regulatory definition as sanitizers by showing bactericidal efficacy of 99.999% in 30 s against staphylococcus aureus atcc 6538 and escherichia coli atcc 11229. these sanitizers showed a broad spectrum of microbicidal activity against both gram-positive and gram-neg ... | 1998 | 9798163 |
| a small outbreak of listeriosis associated with smoked mussels. | two perinatal listeriosis cases in auckland, new zealand, which were diagnosed during november and december 1992 gave histories of consuming brand x smoked mussels. listeria monocytogenes was isolated from an unopened packet of mussels collected from the refrigerator of one of the cases. cultures of l. monocytogenes from the two patients were indistinguishable from those recovered from the mussels by serogrouping and dna macrorestriction analysis using pulsed-field gel electrophoresis (pfge). pf ... | 1998 | 9801198 |
| interferon gamma derived from cd4(+) t cells is sufficient to mediate t helper cell type 1 development. | interferon gamma (ifn-gamma) has been implicated in t helper type 1 (th1) cell development through its ability to optimize interleukin 12 (il-12) production from macrophages and il-12 receptor expression on activated t cells. various systems have suggested a role for ifn-gamma derived from the innate immune system, particularly natural killer (nk) cells, in mediating th1 differentiation in vivo. we tested this requirement by reconstituting t cell and ifn-gamma doubly deficient mice with wild-typ ... | 1998 | 9802977 |
| sequence profile of the parallel beta helix in the pectate lyase superfamily. | the parallel beta helix structure found in the pectate lyase superfamily has been analyzed in detail. a comparative analysis of known structures has revealed a unique sequence profile, with a strong positional preference for specific amino acids oriented toward the interior of the parallel beta helix. using the unique sequence profile, search patterns have been constructed and applied to the sequence databases to identify a subset of proteins that are likely to fold into the parallel beta helix. ... | 1998 | 9724624 |
| bacterial surface proteins recognized by cd4+ t cells during murine infection with listeria monocytogenes. | optimal immunity to the gram-positive pathogen listeria monocytogenes (lm) requires both cd8+ and cd4+ antigen-specific t cell responses. understanding how cd4+ t cells function in an immune response to lm and how bacterial proteins are processed to peptide/mhc class ii complexes in infected cells requires identification of these proteins. using lacz-inducible, lm-specific cd4+ t cells as probes, we identified two immunogenic lm proteins by a novel expression cloning strategy. the antigenic pept ... | 1998 | 9725229 |