Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| targeting and crossing of the human maternofetal barrier by listeria monocytogenes: role of internalin interaction with trophoblast e-cadherin. | listeria monocytogenes produces severe fetoplacental infections in humans. how it targets and crosses the maternofetal barrier is unknown. we used immunohistochemistry to examine the location of l. monocytogenes in placental and amniotic tissue samples obtained from women with fetoplacental listeriosis. the results raised the possibility that l. monocytogenes crosses the maternofetal barrier through the villous syncytiotrophoblast, with secondary infection occurring via the amniotic epithelium. ... | 2004 | 15073336 |
| bacterial invasion: the paradigms of enteroinvasive pathogens. | invasive bacteria actively induce their own uptake by phagocytosis in normally nonphagocytic cells and then either establish a protected niche within which they survive and replicate, or disseminate from cell to cell by means of an actin-based motility process. the mechanisms underlying bacterial entry, phagosome maturation, and dissemination reveal common strategies as well as unique tactics evolved by individual species to establish infection. | 2004 | 15073367 |
| clinicopathological findings in sheep from sardinia showing neurological signs of disease. | histopathological and bacteriological examinations were performed on 178 brains from sardinian sheep which were showing neurological signs. the sheep represented the total number of sheep with neurological syndromes submitted for diagnostic investigations over a three-year period in sardinia. scrapie was detected in 57 cases, cerebrocortical necrosis in 25, intoxication by a typical mediterranean plant (cistus species) was suspected in 25, coenurosis was detected in 11 cases, listeria monocytoge ... | 2004 | 15074327 |
| risk assessment of listeriosis linked to the consumption of two soft cheeses made from raw milk: camembert of normandy and brie of meaux. | this article reports a quantitative risk assessment of human listeriosis linked to the consumption of soft cheeses made from raw milk. risk assessment was based on data purposefully acquired inclusively over the period 2000-2001 for two french cheeses, namely: camembert of normandy and brie of meaux. estimated listeria monocytogenes concentration in raw milk was on average 0.8 and 0.3 cells/l, respectively, in normandy and brie regions. a monte carlo simulation was used to account for the time-t ... | 2004 | 15078309 |
| modeling growth and reduction of microorganisms in foods as functions of temperature and time. | food safety objectives (fsos) are established in order to minimize the risk of foodborne illnesses to consumers, but these have not yet been incorporated into regulatory policy. an fso states the maximum frequency and/or concentration of a microbiological hazard in a food at the time of consumption that provides an acceptable level of protection to the public and leads to a performance criterion for industry. however, in order to be implemented as a regulation, this criterion has to be achievabl ... | 2004 | 15078311 |
| the diversity of listeria monocytogenes strains from 10 icelandic sheep farms. | the purpose of this study was to examine the diversity of listeria monocytogenes strains from healthy sheep, winter feed and environment of sheep farms in iceland. | 2004 | 15078506 |
| effects of divercin v41 combined to nacl content, phenol (liquid smoke) concentration and ph on listeria monocytogenes scotta growth in bhi broth by an experimental design approach. | to investigate the main effects and interactions of different factors : divercin v41 (0-4 ng ml(-1)), nacl content (0.5-5.5% w v(-1)), phenol (liquid smoke) concentration (0-8 ppm), and ph (5.5-7.5) on listeria monocytogenes scotta growth. | 2004 | 15078508 |
| forces generated during actin-based propulsion: a direct measurement by micromanipulation. | dynamic actin networks generate forces for numerous types of movements such as lamellipodia protrusion or the motion of endocytic vesicles. the actin-based propulsive movement of listeria monocytogenes or of functionalized microspheres have been extensively used as model systems to identify the biochemical components that are necessary for actin-based motility. however, quantitative force measurements are required to elucidate the mechanism of force generation, which is still under debate. to di ... | 2004 | 15079054 |
| a comparison of different chemical sanitizers for inactivating escherichia coli o157:h7 and listeria monocytogenes in solution and on apples, lettuce, strawberries, and cantaloupe. | ozone (3 ppm), chlorine dioxide (3 and 5 ppm), chlorinated trisodium phosphate (100- and 200-ppm chlorine), and peroxyacetic acid (80 ppm) were assessed for reduction of escherichia coli o157:h7 and listeria monocytogenes in an aqueous model system and on inoculated produce. initially, sanitizer solutions were inoculated to contain approximately 10(6) cfu/ml of either pathogen, after which aliquots were removed at 15-s intervals over a period of 5 min and approximately plated to determine log re ... | 2004 | 15083724 |
| evaluation of inoculation method and inoculum drying time for their effects on survival and efficiency of recovery of escherichia coli o157:h7, salmonella, and listeria monocytogenes inoculated on the surface of tomatoes. | a study was undertaken to evaluate methods for applying inoculum and to examine the effect of inoculum drying time on survival and recovery of foodborne pathogens inoculated onto the surface of raw, ripe tomatoes. five-strain mixtures of escherichia coli o157:h7, salmonella, or listeria monocytogenes were applied to tomatoes by dip, spot, or spray inoculation methods. inocula were dried for 1 or 24 h at 22 degrees c before tomatoes were treated with water (control) or chlorine (200 micrograms/ml ... | 2004 | 15083725 |
| influence of variations in methodology on populations of listeria monocytogenes recovered from lettuce treated with sanitizers. | the elimination of listeria monocytogenes inoculated onto a piece of cut iceberg lettuce (3.8 by 3.8 cm) by treatment with chlorinated water (200 micrograms/ml free chlorine) and a 0.5% (wt/vol) solution of fit professional line antibacterial cleaner (fit) was investigated. the efficacy of the two sanitizers was not influenced by the composition of the medium used to culture the l. monocytogenes used in the inocula, the number of strains in the inoculum, or the recovery medium used to enumerate ... | 2004 | 15083726 |
| reduction of microbial pathogens during apple cider production using sodium hypochlorite, copper ion, and sonication. | sodium hypochlorite (100 ppm), copper ion water (1 ppm), and sonication (22 to 44 khz and 44 to 48 khz) were assessed individually and in combination for their ability to reduce populations of escherichia coli o157:h7 and listeria monocytogenes on apples and in apple cider. commercial unpasteurized cider was inoculated to contain approximately 10(6) cfu/ml of either pathogen and then sonicated at 44 to 48 khz, with aliquots removed at intervals of 30 to 60 s for up to 5 min and plated to determi ... | 2004 | 15083729 |
| prevalence and genetic diversity of listeria monocytogenes in the tonsils of pigs. | this study was set up to establish the prevalence of listeria monocytogenes in the tonsils of sows and fattening pigs from five finnish slaughterhouses and to evaluate the genetic similarity of l. monocytogenes strains isolated from the tonsils. a total of 271 pig tonsils (132 tonsils from fattening pigs and 139 from sows) from five different slaughterhouses in various parts of finland were studied from june 1999 to march 2000. overall, 14 and 4% of pig tonsils harbored l. monocytogenes and list ... | 2004 | 15083735 |
| antimicrobial edible films and coatings. | increasing consumer demand for microbiologically safer foods, greater convenience, smaller packages, and longer product shelf life is forcing the industry to develop new food-processing, cooking, handling, and packaging strategies. nonfluid ready-to-eat foods are frequently exposed to postprocess surface contamination, leading to a reduction in shelf life. the food industry has at its disposal a wide range of nonedible polypropylene- and polyethylene-based packaging materials and various biodegr ... | 2004 | 15083740 |
| invasion of the central nervous system by intracellular bacteria. | infection of the central nervous system (cns) is a severe and frequently fatal event during the course of many diseases caused by microbes with predominantly intracellular life cycles. examples of these include the facultative intracellular bacteria listeria monocytogenes, mycobacterium tuberculosis, and brucella and salmonella spp. and obligate intracellular microbes of the rickettsiaceae family and tropheryma whipplei. unfortunately, the mechanisms used by intracellular bacterial pathogens to ... | 2004 | 15084504 |
| microorganisms resistant to free-living amoebae. | free-living amoebae feed on bacteria, fungi, and algae. however, some microorganisms have evolved to become resistant to these protists. these amoeba-resistant microorganisms include established pathogens, such as cryptococcus neoformans, legionella spp., chlamydophila pneumoniae, mycobacterium avium, listeria monocytogenes, pseudomonas aeruginosa, and francisella tularensis, and emerging pathogens, such as bosea spp., simkania negevensis, parachlamydia acanthamoebae, and legionella-like amoebal ... | 2004 | 15084508 |
| virulence and cord blood mononuclear cells cytokine production induced by perinatal listeria monocytogenes strains from different phylogenetic lineages. | some of the phylogenetic lineages of listeria monocytogenes are more likely to cause invasive disease in humans than are strains from other phylogenetic lineages. this suggests that strains belonging to these lineages display different levels of pathogenicity. to investigate this, we carried out a plaque-forming assay with ht-29 cells to evaluate the virulence of six perinatal strains from the three lineages that compose the species. all of the strains were largely over the 3.34 cutoff (between ... | 2004 | 15084811 |
| bacterial pathogen incidences in sludge from swedish sewage treatment plants. | this study surveyed the presence of bacterial pathogens in eight swedish sewage treatment plants (stps), with four different treatment methods, focusing on detection of zoonotic bacteria in raw and treated sludge. salmonella spp., listeria monocytogenes, campylobacter coli and jejuni, escherichia coli o157 and indicator bacteria were investigated. samplings were performed from july 2000 to june 2002, resulting in 64 raw sludge samples and 69 treated sludge samples. the samples from raw sludge (6 ... | 2004 | 15087179 |
| unconventional myosin viia and vezatin, two proteins crucial for listeria entry into epithelial cells. | listeria monocytogenes is a bacterial pathogen with the capacity to invade non-phagocytic cells. this dynamic process involves coordinated membrane remodelling and actin cytoskeleton rearrangements. although some of the molecular factors promoting these events have been identified, the driving force allowing internalization is unknown. one of the receptors for l. monocytogenes on epithelial cells is e-cadherin, a transmembrane protein normally involved in homophilic interactions that allow cell- ... | 2004 | 15090598 |
| nmr solution structure of the precursor for carnobacteriocin b2, an antimicrobial peptide from carnobacterium piscicola. | type iia bacteriocins, which are isolated from lactic acid bacteria that are useful for food preservation, are potent antimicrobial peptides with considerable potential as therapeutic agents for gastrointestinal infections in mammals. they are ribosomally synthesized as precursors with an n-terminal leader, typically 18-24 amino acid residues in length, which is cleaved during export from the producing cell. we have chemically synthesized the full precursor of carnobacteriocin b2, precarnobacter ... | 2004 | 15096213 |
| use of pfge to characterize clonal relationships among belgian clinical isolates of listeria monocytogenes. | the belgian listeria reference centre receives between 30 and 50 human clinical strains of listeria monocytogenes per year. in general, epidemiological data are absent or incomplete, preventing recognition of episodes of listeriosis. however, data on a clonal relationship between strains can indirectly give an idea of the occurrence of episodes. human isolates of l. monocytogenes from 2001 were serotyped, their arsenic-cadmium resistance profiles were determined, and they were pulsotyped with th ... | 2004 | 15096548 |
| [study on national active monitoring for food borne pathogens and antimicrobial resistance in china 2001]. | to survey food borne pathogens and antimicrobial resistance in china. | 2004 | 15098478 |
| changes in peritoneal myeloid populations and their proinflammatory cytokine expression during infection with listeria monocytogenes are altered in the absence of gamma/delta t cells. | evidence that gamma/delta t cells play a broad, immunoregulatory role has been accumulating steadily. we show here that myeloid cells are disregulated after peritoneal infection with listeria monocytogenes in mice lacking gamma/delta t cells. inflammatory populations of neutrophils and monocytes recruited to the site of infection remained longer. intracellular cytokine analysis showed that frequencies of myeloid cells producing interleukin-12 and tumor necrosis factor alpha were higher and remai ... | 2004 | 15107460 |
| modulation of the immune system by listeria monocytogenes-mediated gene transfer into mammalian cells. | in this study, we established a method for listeria monocytogenes(lm)-mediated gene transfer into mammalian cells to manipulate the immune response of the host during infection by pathogens. we used the lm-mediated gene transfer method in an in vivo study to manipulate host immune responses against leishmania major(l. major )-infection. the injection of lm modulated the susceptible host into a resistant state against l. major-infection. a more efficient protective effect was obtained with the in ... | 2004 | 15107544 |
| the antilisterial effect of leuconostoc carnosum 4010 and leucocins 4010 in the presence of sodium chloride and sodium nitrite examined in a structured gelatin system. | to further enhance biopreservation of meat products, the antilisterial effect of the newly described protective culture leuconostoc carnosum 4010 and its bacteriocins, leucocins 4010, was examined in the presence of sodium chloride and sodium nitrite in a solid matrix using a structured gelatin system. interaction between listeria monocytogenes 4140 and leuc. carnosum 4010 or the leucocins 4010-resistant mutant l. monocytogenes 4140p showed that the inhibitory effect of leuc. carnosum 4010 in th ... | 2004 | 15109790 |
| improved protection conferred by vaccination with a recombinant vaccinia virus that incorporates a foreign antigen into the extracellular enveloped virion. | recombinant poxviruses have shown promise as vaccine vectors. we hypothesized that improved cellular immune responses could be developed to a foreign antigen by incorporating it as part of the extracellular enveloped virion (eev). we therefore constructed a recombinant vaccinia virus that replaced the cytoplasmic domain of the b5r protein with a test antigen, hiv-1 gag. mice immunized with the virus expressing gag fused to b5r had significantly better primary cd4 t-cell responses than recombinan ... | 2004 | 15110531 |
| whole genome comparisons of serotype 4b and 1/2a strains of the food-borne pathogen listeria monocytogenes reveal new insights into the core genome components of this species. | the genomes of three strains of listeria monocytogenes that have been associated with food-borne illness in the usa were subjected to whole genome comparative analysis. a total of 51, 97 and 69 strain-specific genes were identified in l.monocytogenes strains f2365 (serotype 4b, cheese isolate), f6854 (serotype 1/2a, frankfurter isolate) and h7858 (serotype 4b, meat isolate), respectively. eighty-three genes were restricted to serotype 1/2a and 51 to serotype 4b strains. these strain- and serotyp ... | 2004 | 15115801 |
| fatal meningitis due to listeria monocytogenes in elderly patients with underlying malignancy. | adult patients with malignancies are considered to be at a high risk for listeria monocytogenes meningitis. the microbiology laboratory's database of the university hospital of ioannina, greece, was searched for cases of l. monocytogenes during the period from january 1990 to december 2002. listerial meningitis occurred in three patients: one with brain tumour, one with chronic lymphocytic leukaemia, and one with non-hodgkin's lymphoma. all the patients were older than 70 and they were actively ... | 2004 | 15117098 |
| fascin-mediated propulsion of listeria monocytogenes independent of frequent nucleation by the arp2/3 complex. | actin-dependent propulsion of listeria monocytogenes is thought to require frequent nucleation of actin polymerization by the arp2/3 complex. we demonstrate that l. monocytogenes motility can be separated into an arp2/3-dependent nucleation phase and an arp2/3-independent elongation phase. elongation-based propulsion requires a unique set of biochemical factors in addition to those required for arp2/3-dependent motility. we isolated fascin from brain extracts as the only soluble factor required ... | 2004 | 15117967 |
| recognition of bacteria in the cytosol of mammalian cells by the ubiquitin system. | recent studies have suggested the existence of innate host surveillance systems for the detection of bacteria in the cytosol of mammalian cells. the molecular details of how bacteria are recognized in the cytosol, however, remain unclear. here we examined the fate of salmonella typhimurium, a gram-negative bacterial pathogen that can infect a variety of hosts, in the cytosol of mammalian cells. these bacteria typically occupy a membrane bound compartment, the salmonella-containing vacuole (scv), ... | 2004 | 15120074 |
| listeriosis. | 2004 | 15121906 | |
| microbial-gut interactions in health and disease. mucosal immune responses. | the host gastrointestinal tract is exposed to countless numbers of foreign antigens and has embedded a unique and complex network of immunological and non-immunological mechanisms, often termed the gastrointestinal 'mucosal barrier', to protect the host from potentially harmful pathogens while at the same time 'tolerating' other resident microbes to allow absorption and utilization of nutrients. of the many important roles of this barrier, it is the distinct responsibility of the mucosal immune ... | 2004 | 15123077 |
| coinfection with listeria monocytogenes potentlxtes the response of balb/c mice against leishmania major. | protection against l. major is dependent on the stimulation of an anti-leishmanial t helper1 (th1) response and the production of interferon (ifn)-y. balb/c mice develop a th2 response and fatal infection with leishmania major. strategies that boost il-12 production have shown to be protective. the innate response to listeria monocytogenes is associated with il-12 production. the co-infection of balb/c mice with l. monocytogenes attenuates the course of l. major infection. lesion sizes were smal ... | 2004 | 15125539 |
| increased atpase activity is responsible for acid sensitivity of nisin-resistant listeria monocytogenes atcc 700302. | the growth of the foodborne pathogen listeria monocytogenes can be controlled by nisin, an antimicrobial peptide. a spontaneous mutant of l. monocytogenes shows both resistance to nisin and increased acid sensitivity compared to the wild type. changes in the cell membrane correlated with nisin resistance, but the mechanism for acid sensitivity appears unrelated. when hydrochloric or lactic acid is added to cultures, intracellular atp levels drop significantly in the mutant (p < 0.01) compared to ... | 2004 | 15128523 |
| molecular and physiological analysis of the role of osmolyte transporters betl, gbu, and opuc in growth of listeria monocytogenes at low temperatures. | listeria monocytogenes is a ubiquitous food-borne pathogen found widely distributed in nature as well as an undesirable contaminant in a variety of fresh and processed foods. this ubiquity can be at least partly explained by the ability of the organism to grow at high osmolarity and reduced temperatures, a consequence of its ability to accumulate osmo- and cryoprotective compounds termed osmolytes. single and multiple deletions of the known osmolyte transporters betl, gbu, and opuc significantly ... | 2004 | 15128551 |
| osmotic stress leads to decreased intracellular ph of listeria monocytogenes as determined by fluorescence ratio-imaging microscopy. | intracellular ph (ph(i)) of listeria monocytogenes was determined after exposure to nacl or sorbitol in liquid and solid media (agar). both compounds decreased ph(i), and recovery on solid medium was impaired compared to that in liquid medium. n,n'-dicyclohexylcarbodiimide abolished ph(i) recovery, and lowering a(w) with glycerol showed no effect on ph(i). | 2004 | 15128587 |
| the ability of two listeria monocytogenes vaccines targeting human papillomavirus-16 e7 to induce an antitumor response correlates with myeloid dendritic cell function. | previous work from our laboratory has shown that lm-llo-e7 induces complete regression of approximately 75% of established tc-1 tumors, whereas lm-e7 only slows the growth of such tumors. in this study, we examine the effects of lm-llo-e7 vs lm-e7 on apcs. we hypothesize that the difference in antitumor efficacy of the two vaccines is due to the ability of each of these vectors to render immature dendritic cells (dcs) effective apcs in terms of mhc class ii or costimulatory molecule expression. ... | 2004 | 15128786 |
| global analysis of gene expression in an rpon mutant of listeria monocytogenes. | the role of the alternative sigma(54) factor, encoded by the rpon gene, was investigated in listeria monocytogenes by comparing the global gene expression of the wild-type egde strain and an rpon mutant. gene expression, using whole-genome macroarrays, and protein content, using two-dimensional gel electrophoresis, were analysed. seventy-seven genes and nine proteins, whose expression was modulated in the rpon mutant as compared to the wild-type strain, were identified. most of the modifications ... | 2004 | 15133119 |
| apoptosis and loss of virus-specific cd8+ t-cell memory. | cd8(+) t-cell memory to viruses is stable in the absence but volatile in the presence of other infections. apoptotic events that occur early in acute infections delete pre-existing memory t cells, leaving the host with reduced memory (except for cross-reactive responses) to previously encountered viruses. apoptotic events also silence the acute immune response, leaving the host with a residual population of memory t cells. persistent infections can induce apoptotic deletions of memory t cells th ... | 2004 | 15134774 |
| the role of cd1d in the immune response against listeria infection. | to address the role of cd1d in mucosal immune regulation in bacterial infection, we infected cd1d ko mice with listeria monocytogenes (lm). a higher systemic bacterial burden associated with inflammatory lymphocytic infiltrations within the intestine was found in cd1d ko compared with wild type (wt) mice. lm induced strong ifn-gamma mrna expression in the liver of wt and the intestine of cd1d ko mice, thus demonstrating the dual, opposing immune activities of ifn-gamma in lm infection that is de ... | 2004 | 15135293 |
| screening of glutamate decarboxylase activity and bile salt resistance of human asymptomatic carriage, clinical, food, and environmental isolates of listeria monocytogenes. | following consumption, stomach acidity is the first major barrier encountered by the food-borne pathogen listeria monocytogenes. analysis of low ph sensitivity and glutamate decarboxylase (gad) acid resistance system of 14 isolates of l. monocytogenes carried asymptomatically by humans showed that levels of gad activity were subjected to strain variation. similar variations were observed for strains responsible for 18 cases of listeriosis, whereas in comparison, 13 strains isolated from food and ... | 2004 | 15135585 |
| overview of listeria monocytogenes contamination in japan. | listeriosis is a relatively rare foodborne illness but can be life threatening with high fatality rates. in japan, the incidence of listeriosis has been very low for the past 40 years compared with that of western europe and north america. we hypothesized that less listeria monocytogenes contamination in japanese foods would be related to the lower incidence in japan. for this purpose, we collected data of japanese foods contaminated with l. monocytogenes, mainly from japanese-written reports, a ... | 2004 | 15135952 |
| use of monoclonal antibodies that recognize p60 for identification of listeria monocytogenes. | listeria monocytogenes causes major food-borne outbreaks of disease worldwide. specific identification of this microorganism is of utmost importance to public health and industry. listeria species are known to secrete a 60-kda protein collectively termed p60, which is encoded by the iap (invasion-associated protein) gene and secreted in large quantities into the growth media. p60 is a highly immunogenic murein hydrolase that is essential for cell division. due to these properties, p60 is an idea ... | 2004 | 15138168 |
| potential therapeutic applications of recombinant, invasive e. coli. | an invasive escherichia coli expressing the inv gene from yersinia pseudotuberculosis was used as a vector for protein delivery to mammalian epithelial cells. upon incubation with beta1-integrin-expressing mammalian cells, the bacteria are internalized, allowing bacteria-encoded proteins to function from within the mammalian cell. these bacteria are eventually processed in the host phagosome where they are destroyed. expression of listeriolysin o from listeria monocytogenes in the bacterium and ... | 2004 | 15141160 |
| meropenem therapy failure in listeria monocytogenes infection. | listeria monocytogenes is highly susceptible to meropenem in vitro, but data on the efficacy of meropenem in clinical cases of listeriosis are scarce. described here is the case of a child with aplastic anemia who acquired nosocomial listeriosis and failed to respond to initial meropenem therapy. resolution of fever was not noted after 5 days of therapy with meropenem and, more importantly, clinical worsening was observed during this period. the patient began to improve after ampicillin was intr ... | 2004 | 15141335 |
| studies of listeria monocytogenes-antibody binding using electro-orientation. | an electro-optical (eo) approach has been used for studies of listeria monocytogenes-antibody binding. the eo analyzer, which has been developed at the state research center for applied microbiology, obolensk, was used as a basic instrument for eo measurements. ac electro-kinetic effects depend on dielectric properties of bioparticles, their composition, morphology, the medium, and the frequency of applied electrical field. electro-orientational spectra were used for discrimination of bacteria b ... | 2004 | 15142611 |
| a molecular marker for evaluating the pathogenic potential of foodborne listeria monocytogenes. | internalin mediates entry of listeria monocytogenes into some human cultured cell lines and crossing of the intestinal barrier in transgenic mice expressing its receptor, human e-cadherin, in enterocytes. the relevance of these findings for humans is challenged by the observation that some l. monocytogenes isolates express a truncated nonfunctional form of internalin. | 2004 | 15143478 |
| impairment of growth of listeria monocytogenes in thp-1 macrophages by granulocyte macrophage colony-stimulating factor: release of tumor necrosis factor-alpha and nitric oxide. | listeria monocytogenes tends to survive in phagocytes. granulocyte macrophage colony-stimulating factor (gm-csf) protects mice against l. monocytogenes infection, and mice knocked out for the gm-csf gene are more susceptible to these infections. | 2004 | 15143479 |
| mode of action of lactococcin r produced by lactococcus lactis r. | we investigated the mode of action and factors affecting adsorption of lactoccocin r produced by lactococcus lactis r. it was found that lactococcin r adsorbed to all gram-positive but not to the gram-negative bacteria tested and its adsorption was dependent on ph. it was observed that the binding of lactococcin r was prevented by anions of several salts (cl-, po4(-3)) and lipoteichoic acid. pretreatments of sensitive cells and cell walls with detergents, organic solvents or enzymes did not redu ... | 2004 | 15146973 |
| inverted pathogenicity: the use of pathogen-specific molecular mechanisms for prevention or therapy of disease. | the term "inverted pathogenicity" stands for the exploitation of microbial toxins, virulence factors and cellular mechanisms for preventive or therapeutic purposes. this mini-review will focus on the major pathogenicity concept of salmonella and yersinia and how to use its underlying molecular principle for the development of a novel vaccination strategy. both bacterial species employ a type iii secretion system which mediates secretion and direct delivery (translocation) of antihost factors int ... | 2004 | 15149032 |
| the rna-binding protein hfq of listeria monocytogenes: role in stress tolerance and virulence. | in gram-negative bacteria, the rna-binding protein hfq has emerged as an important regulatory factor in a variety of physiological processes, including stress resistance and virulence. in escherichia coli, hfq modulates the stability or the translation of mrnas and interacts with numerous small regulatory rnas. here, we studied the role of hfq in the stress tolerance and virulence of the gram-positive food-borne human pathogen listeria monocytogenes. we present evidence that hfq is involved in t ... | 2004 | 15150220 |
| polyphenol oxidase activity as a potential intrinsic index of adequate thermal pasteurization of apple cider. | in response to increasing concerns about microbial safety of apple cider, the u.s. food and drug administration has mandated treatment of cider sufficient for a 5-log reduction of the target pathogen. pasteurization has been suggested as the treatment most likely to achieve a 5-log reduction, with escherichia coli o157:h7 as the target pathogen. regulators and processors need a reliable method for verifying pasteurization, and apple cider polyphenol oxidase (ppo) activity was studied as a potent ... | 2004 | 15151226 |
| effectiveness of acidic calcium sulfate with propionic and lactic acid and lactates as postprocessing dipping solutions to control listeria monocytogenes on frankfurters with or without potassium lactate and stored vacuum packaged at 4.5 degrees c. | the safety of ready-to-eat meat products such as frankfurters can be enhanced by treating with approved antimicrobial substances to control the growth of listeria monocytogenes. we evaluated the effectiveness of acidic calcium sulfate with propionic and lactic acid, potassium lactate, or lactic acid postprocessing dipping solutions to control l. monocytogenes inoculated (ca. 10(8) cfu/ml) onto the surface of frankfurters with or without potassium lactate and stored in vacuum packages at 4.5 degr ... | 2004 | 15151227 |
| encapsulation of nisin and lysozyme in liposomes enhances efficacy against listeria monocytogenes. | the efficacy and stability against listeria monocytogenes of nisin and lysozyme encapsulated in phospholipid liposomes was evaluated. antimicrobial-containing liposomes were prepared by hydrating dried lipids with buffer containing nisin, nisin plus the fluorescence probe calcein, or calcein and lysozyme. mixtures were then centrifuged and sonicated, and encapsulated liposomes were collected using size-exclusion chromatography. antimicrobial concentration in liposomes was determined by bicinchon ... | 2004 | 15151228 |
| isolation, identification, and selection of lactic acid bacteria from alfalfa sprouts for competitive inhibition of foodborne pathogens. | several studies have investigated the control of pathogens on alfalfa sprouts, and some treatments have been shown to be effective in reducing pathogen populations. however, control methods investigated thus far only provide pathogen control at a given point in the sprouting process and can affect germination. competitive inhibition of pathogens with lactic acid bacteria might provide pathogen control throughout the sprouting process and up to consumption. the purpose of this study was to isolat ... | 2004 | 15151232 |
| molecular weight of chitosan influences antimicrobial activity in oil-in-water emulsions. | the objective of this study was to evaluate the antimicrobial efficiency of chitosans in oil-in-water emulsions. model emulsions were prepared with 20% corn oil, 1.5% tween 20, 1.5% trypticase soy broth, 0.58% acetic acid, and chitosan polysaccharide or chitosan oligosaccharide in concentrations of 0, 0.1, 0.2, 0.5, and 0.7%. a control containing hcl was included to determine the role of acetic acid in the overall antibacterial activity. the ph of samples and controls was adjusted to 4.5. emulsi ... | 2004 | 15151233 |
| sensitization of gram-negative and gram-positive bacteria to jenseniin g by sublethal injury. | jenseniin g, a bacteriocin produced by propionibacterium thoenii p126, is active against related propionibacteria and some lactic acid bacteria and is sporostatic to botulinal spores. the objective of this study was to evaluate the effects of sublethal stress on jenseniin g activity. bacillus cereus, enterococcus faecalis, escherichia coli, listeria monocytogenes, salmonella typhimurium, shigella flexneri, staphylococcus aureus, and yersinia enterocolitica were subjected to temperature, acid, an ... | 2004 | 15151241 |
| inactivation of pathogenic bacteria by cucumber volatiles (e,z)-2,6-nonadienal and (e)-2-nonenal. | the effects of (e,z)-2,6-nonadienal (nde) and (e)-2-nonenal (ne) on bacillus cereus, escherichia coli o157:h7, listeria monocytogenes, and salmonella typhimurium were investigated. a suspension of each organism of 6 to 9 log cfu/ml was incubated for 1 h at 37 degrees c in brain heart infusion solution that contained 0 to 500 or 1,000 ppm of nde or ne. depending on concentration, exposure to either nde or ne caused a reduction in cfu of each organism. treatment with 250 and 500 ppm nde completely ... | 2004 | 15151242 |
| evaluation of nisin-coated cellulose casings for the control of listeria monocytogenes inoculated onto the surface of commercially prepared frankfurters. | commercially prepared frankfurters were formulated with and without approximately 1.4% potassium lactate and 0.1% sodium diacetate and were subsequently processed in cellulose casings coated with and without nisin (approximately 50,000 iu per square inch of internal surface area) to control the outgrowth of listeria monocytogenes during refrigerated storage. the frankfurters were inoculated with approximately 5 log cfu per package of a five-strain mixture of l. monocytogenes and then vacuum seal ... | 2004 | 15151243 |
| prevalence and growth of listeria on naturally contaminated smoked salmon over 28 days of storage at 4 degrees c. | only limited data are available on the growth characteristics of listeria in naturally contaminated ready-to-eat foods. to evaluate listeria contamination patterns and growth in smoked salmon, 72 smoked salmon product samples from two processing plants were tested for listeria spp. and l. monocytogenes. samples were divided into four approximately equal portions: one portion was tested on receipt, and the other three were vacuum sealed and stored at 4 degrees c for 7, 14, and 28 days. listeria t ... | 2004 | 15151244 |
| delayed presentation of prosthetic joint infection due to listeria monocytogenes. | infection with listeria monocytogenes is rare and has been described in prosthetic valves, stent grafts and prosthetic joints. the route of infection appears to be haematogenous. the choice between conservative treatment with antibiotics or surgical treatment with debridement and revision of the components remains controversial. the best antibiotic treatment is not known with ampicillin being the first choice in most cases. prosthetic infections with listeria monocytogenes usually occur in patie ... | 2004 | 15161131 |
| investigation of the effectiveness of ascopyrone p as a food preservative. | ascopyrone p (app), a novel antibacterial from fungi, was evaluated as a food preservative. efficacy was generally assessed by comparing the time taken for test strains to grow to 10(6) cfu/g in food +/- app. in chilled chicken soup, 2000 mg kg-1 app prevented bacillus cereus, listeria monocytogenes, pseudomonas fluorescens, salmonella and escherichia coli reaching this threshold for >60 days. good activity was also observed at 500-1000 mg kg-1 but not against l. monocytogenes. no activity was o ... | 2004 | 15163588 |
| evaluation of the bax system for detection of listeria monocytogenes in foods: collaborative study. | a multilaboratory study was conducted to compare the automated bax system and the standard cultural methods for detection of listeria monocytogenes in foods. six food types (frankfurters, soft cheese, smoked salmon, raw, ground beef, fresh radishes, and frozen peas) were analyzed by each method. for each food type, 3 inoculation levels were tested: high (average of 2 cfu/g), low (average of 0.2 cfu/g) and uninoculated controls. a total of 25 laboratories representing government and industry part ... | 2004 | 15164834 |
| comparison of selective and nonselective primary enrichments for the detection of listeria monocytogenes in cheese. | a completely selective enrichment procedure was compared with two partially nonselective ones for the detection of listeria monocytogenes in cheeses. after enrichment for approximately 48 h, the enrichment media were streaked on selective agars and presumptive listeria colonies were confirmed using pcr. in some cases, pcr was also performed directly on the enrichment broth. the conventional, completely selective enrichment procedure was not always the best choice for the detection of stressed l. ... | 2004 | 15172481 |
| a process for controlling intracellular bacterial infections induced by membrane injury. | strategies for inhibiting phagolysosome fusion are essential for the intracellular survival and replication of many pathogens. we found that the lysosomal synaptotagmin syt vii is required for a mechanism that promotes phagolysosomal fusion and limits the intracellular growth of pathogenic bacteria. syt vii was required for a form of ca2+-dependent phagolysosome fusion that is analogous to ca2+-regulated exocytosis of lysosomes, which can be triggered by membrane injury. bacterial type iii secre ... | 2004 | 15178804 |
| linearized kinetic model of listeria monocytogenes biofilm growth. | in this study the dynamics of biofilm formation on aluminum has been investigated. the process of cell growth has been observed using fluorescence microscopy. it has been confirmed that the process of biofilm formation can be represented as a sum of two separate processes: cell adhesion and colony proliferation. the derived set of equations describes kinetics of surface population growth and characteristic times for adsorption and combined growth processes, including characteristic time for the ... | 2004 | 15179574 |
| novel expression system for large-scale production and purification of recombinant class iia bacteriocins and its application to piscicolin 126. | piscicolin 126 is a class iia bacteriocin isolated from carnobacterium piscicola jg126 that exhibits strong activity against listeria monocytogenes. the gene encoding mature piscicolin 126 (m-pisa) was cloned into an escherichia coli expression system and expressed as a thioredoxin-piscicolin 126 fusion protein that was purified by affinity chromatography. purified recombinant piscicolin 126 was obtained after cnbr cleavage of the fusion protein followed by reversed-phase chromatography. recombi ... | 2004 | 15184123 |
| identification of sigma factor sigma b-controlled genes and their impact on acid stress, high hydrostatic pressure, and freeze survival in listeria monocytogenes egd-e. | the gene encoding the alternative sigma factor sigma(b) in listeria monocytogenes is induced upon exposure of cells to several stresses. in this study, we investigated the impact of a sigb null mutation on the survival of l. monocytogenes egd-e at low ph, during high-hydrostatic-pressure treatment, and during freezing. the survival of delta sigb mutant exponential-phase cells at ph 2.5 was 10,000-fold lower than the survival of egd-e wild-type cells. moreover, the delta sigb mutant failed to sho ... | 2004 | 15184144 |
| modeling the rate of attachment of listeria monocytogenes, pantoea agglomerans, and pseudomonas fluorescens to, and the probability of their detachment from, potato tissue at 10 degrees c. | the rate of attachment of bacteria to, and their subsequent detachment from, the cut surface of raw potato tissue was measured and modeled by using mathematical approaches that allowed detailed objective comparisons of adhesion processes under different conditions. attachment was rapid and reached equilibrium after contact for 60 min. a new method to measure the probability of detachment was developed and modeled, revealing that the probability of detachment for pseudomonas fluorescens remained ... | 2004 | 15184157 |
| identification and characterization of the novel lysm domain-containing surface protein sep from lactobacillus fermentum br11 and its use as a peptide fusion partner in lactobacillus and lactococcus. | examination of supernatant fractions from broth cultures of lactobacillus fermentum br11 revealed the presence of a number of proteins, including a 27-kda protein termed sep. the amino-terminal sequence of sep was determined, and the gene encoding it was cloned and sequenced. sep is a 205-amino-acid protein and contains a 30-amino-acid secretion signal and has overall homology (between 39 and 92% identity) with similarly sized proteins of lactobacillus reuteri, enterococcus faecium, streptococcu ... | 2004 | 15184172 |
| new listeria monocytogenes prfa* mutants, transcriptional properties of prfa* proteins and structure-function of the virulence regulator prfa. | prfa, a transcription factor structurally related to crp/fnr, activates listeria monocytogenes virulence genes during intracellular infection. we report two new prfa* mutations causing the constitutive overexpression of the prfa regulon. leu-140phe lies in alphad adjacent to the dna-binding motif in the c-terminal domain, like a previously characterized prfa* mutation (gly-145ser). ile-45ser, in contrast, maps to the n-terminal beta-roll, a structure similar to that of the crp camp binding site. ... | 2004 | 15186408 |
| the autolytic phenotype of bacillus thuringiensis. | to evaluate the autolytic phenotype of bacillus thuringiensis. | 2004 | 15186453 |
| development of tcr alpha beta cd8 alpha alpha intestinal intraepithelial lymphocytes is promoted by interleukin-15-producing epithelial cells constitutively stimulated by gram-negative bacteria via tlr4. | the microbes present in the intestine have a strong influence on the development and maturation of lymphoid organs. the cross-talk mechanisms between intestinal intraepithelial lymphocytes (i-iel) and noninvasive microbes are still poorly understood. the influence of microbes and lipopolysaccharides on the development of i-iel, especially the tcr alpha beta(+) cd8 alpha alpha subset, was investigated using the different tlr4-mutant mouse strains c3h/hej, balb/lps(d), and c57bl/10sccr. intestinal ... | 2004 | 15187438 |
| [influence of temperature on the variability of listeria monocytogenes in the course of its prolonged existence in soil-packed water-circulating columns]. | the capacity of l. monocytogenes for prolonged existence in the soil at different temperatures (18-20 degrees c and 6-8 degrees c) has been shown. the viability of these bacteria in the soil depends both on their properties and the temperature factor. low temperatures (6-8 degrees c) ensure, on the whole, the stable preservation of the biological properties of the bacteria. more pronounced variability of l. monocytogenes at a temperature of 18-20 degrees c is an adaptive property, ensuring high ... | 2004 | 15188555 |
| inhibition of tnf-alpha production in thp-1 macrophages by glatiramer acetate does not alter their susceptibility to infection by listeria monocytogenes and does not impair the efficacy of ampicillin or moxifloxacin against intracellular bacteria. | 2004 | 15190038 | |
| diversity of listeria monocytogenes isolates of human and food origin studied by serotyping, automated ribotyping and pulsed-field gel electrophoresis. | automated ribotyping, pulsed-field gel electrophoresis (pfge) and serotyping were evaluated for the epidemiological study of isolates of listeria monocytogenes collected in finland in 1997-1999 from human blood (n = 116) and the food industry (n = 72). the isolates divided into six serotypes, 23 ecori ribotypes, 54 asci pfge types, and 57 final subtypes if all results were combined. the discrimination index of ribotyping was lower (0.873) than that of pfge (0.946). two final subtypes dominated a ... | 2004 | 15191386 |
| interactions between high pressure homogenization and antimicrobial activity of lysozyme and lactoperoxidase. | it was the objective of this work to evaluate the effect of high pressure homogenization on the activity of antimicrobial enzymes such as lysozyme and lactoperoxidase against a selected group of gram positive and gram negative species inoculated in skim milk. lactobacillus helveticus, lactobacillus plantarum and listeria monocytogenes were the most pressure resistant species while bacillus subtilis, pseudomonas putida, salmonella typhimurium, staphylococcus aureus, proteus vulgaris and salmonell ... | 2004 | 15193800 |
| recombinant escherichia coli as a gene delivery vector into airway epithelial cells. | to transfer genes into airway epithelial cells, we have generated auxotrophic dap escherichia coli bm2710 mutant that expresses the invasin of yersinia pseudotuberculosis and the listeriolysin of listeria monocytogenes. e. coli bm2710 harboring a plasmid carrying the gfp gene was incubated with immortalized normal or cystic fibrosis (cf) airway epithelial cells or with primary bronchial epithelial cells grown as an explant-outgrowth cell culture model. approximately 2% of immortalized cells expr ... | 2004 | 15196763 |
| the role of substrate curvature in actin-based pushing forces. | the extension of the plasma membrane during cell crawling or spreading is known to require actin polymerization; however, the question of how pushing forces derive from actin polymerization remains open. a leading theory (herein referred to as elastic propulsion) illustrates how elastic stresses in networks growing on curved surfaces can result in forces that push particles. to date all examples of reconstituted motility have used curved surfaces, raising the possibility that such squeezing forc ... | 2004 | 15203003 |
| actin polymerization: forcing flat faces forward. | actin polymerization has been shown to be sufficient to propel curved objects, for example beads and vesicles coated with the listeria monocytogenes protein acta. recent studies suggest that actin polymerization on flat surfaces can also provide the propulsive force to push them forward. | 2004 | 15203017 |
| brainstem and cranial nerve abnormalities: listeriosis, otitis media/interna, and pituitary abscess syndrome. | this article reviews three disorders associated with multiple asymmetric cranial nerve deficits in ruminants: encephalitic listeriosis,otitis media/interna, and pituitary abscess syndrome. emphasis is placed on encephalitic listeriosis, an infectious disease of the brainstem and cranial nerves caused by listeria monocytogenes. the epidemiology, pathophysiology, clinical manifestations, diagnosis,and treatment of encephalitic listeriosis are reviewed, and differences between cattle and small rumi ... | 2004 | 15203225 |
| listeria monocytogenes pneumonia in a cirrhotic child. | a 13-year-old girl with cirrhosis and cyanotic heart disease was admitted with a three-day history of pneumonia. the chest roentgenogram revealed left-sided pleural effusion and cultures from the pleural fluid yielded listeria monocytogenes. the authors discuss the epidemiologic, clinical, and pathophysiological aspects of l. monocytogenes pneumonia and its association with cirrhosis. | 2004 | 15206516 |
| effects of applying safe2o poultry wash to broiler wings on shelf life, listeria monocytogenes, pseudomonads, staphylococcus species, and psychrotrophic bacteria levels after three, seven, and ten days of storage. | bacterial contamination of raw processed poultry continues to be of concern to consumers as well as regulatory and health officials. for many years wings were considered a low-value product; therefore, shelf life of wings was not a major concern. due to changes in consumer attitudes and increases in the fast-food market, wings are now a valuable commodity. because wings have a shorter shelf life than most other raw poultry products, acceptable intervention to decrease the population of associate ... | 2004 | 15206635 |
| a rare case of listeria monocytogenes presenting as prosthetic valve bacterial endocarditis and aortic root abscess. | listeria monocytogenes is a gram-positive bacillus that is rarely associated with infections in the general population. those susceptible to this pathogen include neonates, pregnant women, and the immunocompromised. the most common clinical manifestations of listeriosis are bacteremia and meningitis. endocarditis caused by l. monocytogenes is rare with less than 60 cases reported in the world literature. we report the case of an 81-year-old man who suffered aortic prosthetic valve listeria endoc ... | 2004 | 15209721 |
| listeria monocytogenes as a vaccine vector: virulence attenuation or existing antivector immunity does not diminish therapeutic efficacy. | the bacterium l. monocytogenes is a proposed vaccine carrier based upon the observation that this pathogen replicates within the intracytoplasmic environment facilitating delivery of ag to the endogenous ag processing and presentation pathway with subsequent stimulation of peptide specific mhc class i-restricted cd8(+) effector cells. in this report, we evaluate virulence-attenuated strains of listeria monocytogenes as vaccine vectors and examine whether existing antivector (antilisterial) immun ... | 2004 | 15210801 |
| intestinal p glycoprotein acts as a natural defense mechanism against listeria monocytogenes. | mechanisms by which the intestinal epithelium resists invasion by food-borne pathogens such as listeria monocytogenes are an evolving area of research. intestinal p glycoprotein is well known to limit the absorption of xenobiotics and is believed to act as a cytotoxic defense mechanism. the aim of this study was to determine if intestinal p glycoprotein is involved in host defense against l. monocytogenes. caco-2 cells and a p-glycoprotein-overexpressing subclone (caco-2/mdr) were employed in ad ... | 2004 | 15213126 |
| oral inoculation of a/j mice for detection of invasiveness differences between listeria monocytogenes epidemic and environmental strains. | four-week-old harlan a/j mice were orally infected with six epidemic and six environmental strains of listeria monocytogenes. epidemic strains were significantly more invasive as a group than were environmental strains (p < 0.05), and the intestines of some mice infected with epidemic strains had extensive hemorrhage. mice inoculated with epidemic strains were significantly more likely to become systemically infected than mice inoculated with environmental strains (p < 0.01). | 2004 | 15213183 |
| canine tonsillitis associated with listeria monocytogenes. | 2004 | 15214521 | |
| bacteriocin-like substance production by bacillus licheniformis strain p40. | to investigate the production of bacteriocin-like compounds by bacillus spp. isolated from the amazon basin. | 2004 | 15214721 |
| comparative acid stress response of listeria monocytogenes, escherichia coli o157:h7 and salmonella typhimurium after habituation at different ph conditions. | the aim of the study was to evaluate the effect of habituation at different ph conditions on the acid resistance of listeria monocytogenes, escherichia coli o157:h7 and salmonella enterica serotype typhimurium, and to identify potential differences between the adaptive responses of the three pathogens. | 2004 | 15214733 |
| survival and recovery of escherichia coli o157:h7, salmonella, and listeria monocytogenes on lettuce and parsley as affected by method of inoculation, time between inoculation and analysis, and treatment with chlorinated water. | the effects of method for applying inoculum and of drying time after inoculation on survival and recovery of foodborne pathogens on iceberg lettuce and parsley were studied. five-strain mixtures of escherichia coli o157:h7, salmonella, or listeria monocytogenes were applied to lettuce and parsley by dip, spot, or spray inoculation methods. inocula were dried for 2 h at 22 degrees c or for 2 h at 22 degrees c and then 22 h at 4 degrees c before being treated with water (control) or chlorine (200 ... | 2004 | 15222533 |
| impact of intervention strategies on listeria contamination patterns in crawfish processing plants: a longitudinal study. | two ready-to-eat crawfish processing plants were monitored for 2 years to study the impact of listeria control strategies, including employee training and targeted sanitation procedures, on listeria contamination. environmental, raw material, and finished product samples were collected weekly during the main processing months (april to june) and tested for listeria spp. and listeria monocytogenes. before implementation of control strategies (year 1), the two processing plants showed listeria spp ... | 2004 | 15222544 |
| survival of listeria monocytogenes strain h7762 and resistance to simulated gastric fluid following exposure to frankfurter exudate. | listeria monocytogenes strain h7762, a frankfurter isolate, was tested to determine whether it was able to survive at 4 degrees c in frankfurter pack fluid (exudate) and to determine whether food exposure affects its acid sensitivity. cultures were sampled and tested for acid sensitivity by challenge with simulated gastric fluid (sgf). sgf challenges performed immediately after inoculation revealed that between 20 and 26% of the cells survived the full 30 min of sgf challenge regardless of wheth ... | 2004 | 15222545 |
| efficacy of chlorine and a peroxyacetic acid sanitizer in killing listeria monocytogenes on iceberg and romaine lettuce using simulated commercial processing conditions. | the efficacy of chlorine (100 microg/ml) and a peroxyacetic acid sanitizer (80 microg/ml; tsunami 100) in killing listeria monocytogenes inoculated at populations of 1 to 2, 2 to 3, and 4 to 5 log cfu/g of iceberg lettuce pieces, shredded iceberg lettuce, and romaine lettuce pieces was determined by treatment conditions simulating those used by a commercial fresh-cut lettuce processor. the lettuce/treatment solution ratio was 1:100 (wt/vol), treatment temperature was 4 degrees c, and total treat ... | 2004 | 15222557 |
| in vitro antimicrobial activity of essential oils from aromatic plants against selected foodborne pathogens. | the purpose of this study was to examine the effectiveness of selected essential oils for the control of growth and survival of pathogenic microorganisms of significant importance in food hygiene and to determine whether the antimicrobial effect was due to the major compounds of the oils. mic and mbc were determined by the tube dilution method. essential oils from thymus vulgaris from spain and france, salvia sclarea, salvia officinalis, salvia lavandulifolia, lavandula latifolia, lavandula angu ... | 2004 | 15222560 |
| fbpa, a novel multifunctional listeria monocytogenes virulence factor. | listeria monocytogenes is a gram-positive intracellular bacterium responsible for severe opportunistic infections in humans and animals. signature-tagged mutagenesis (stm) was used to identify a gene named fbpa, required for efficient liver colonization of mice inoculated intravenously. fbpa was also shown to be required for intestinal and liver colonization after oral infection of transgenic mice expressing human e-cadherin. fbpa encodes a 570-amino-acid polypeptide that has strong homologies t ... | 2004 | 15228540 |
| clinical and histopathological aspects of naturally occurring mastitis caused by listeria monocytogenes in cattle and ewes. | listeria monocytogenes was isolated from the milk of two cows and two sheep with mastitis in one quarter and one udder half. the animals were observed over a period of 2-12 months. clinical examination of the udder, bacteriological examinations and determination of somatic cell counts of milk samples were performed monthly. all four cases suffered from a subclinical mastitis characterized by an elevated somatic cell count (0.8-10.1 x 10(6) cells/ml), a persistent shedding of listeria and by a no ... | 2004 | 15228552 |
| a rickettsia wasp-like protein activates the arp2/3 complex and mediates actin-based motility. | spotted fever group rickettsia are obligate intracellular pathogens that exploit the host cell actin cytoskeleton to promote motility and cell-to-cell spread. although other pathogens such as listeria monocytogenes use an arp2/3 complex-dependent nucleation mechanism to generate comet tails consisting of y-branched filament arrays, rickettsia polymerize tails consisting of unbranched filaments by a previously unknown mechanism. we identified genes in several rickettsia species encoding proteins ... | 2004 | 15236643 |
| development of polythene films for food packaging activated with an antilisterial bacteriocin from lactobacillus curvatus 32y. | the aims of this work were to (i) use a bacteriocin produced by lactobacillus curvatus 32y active against listeria monocytogenes to activate polythene films by different methods, (ii) implement a large-scale process for antilisterial polythene films production and (iii) verify the efficacy of the developed films in inhibiting the growth of l. monocytogenes during the storage of meat products. | 2004 | 15239697 |
| new chromogenic plating media for detection and enumeration of pathogenic listeria spp.--an overview. | in recent years a number of selective chromogenic plating media for pathogenic listeria spp. have been developed and marketed. their advantages are direct detection and enumeration of pathogenic listeria spp. utilizing cleavage of substrates by the virulence factor phosphatidylinositol-phospholipase c (pi-plc) and, to a lesser extent, by phosphatidylcholin-phospholipase c (pc-plc). there are two groups of such media: the first utilizes cleavage by pi-plc of l-alpha-phosphatidyl-inositol, forming ... | 2004 | 15240069 |