| innate immune responses in nf-kappab-repressing factor-deficient mice. | nf-kappab-repressing factor (nrf) is a transcriptional silencer protein that specifically counteracts the basal activity of several nf-kappab-dependent promoters by direct binding to specific neighboring dna sequences. in cell culture experiments, the reduction of nrf mrna leads to a derepression of beta interferon, interleukin-8, and inducible nitric oxide synthase transcription. the x chromosome-located single-copy nrf gene is ubiquitously expressed and encodes a protein of 690 amino acids. th ... | 2006 | 16354699 |
| growth inhibition of escherichia coli o157:h7 and listeria monocytogenes by carvacrol and eugenol encapsulated in surfactant micelles. | growth inhibition of four strains of escherichia coli o157:h7 (h1730, f4546, 932, and e0019) and listeria monocytogenes (scott a, 101, 108, and 310) by essential oil components (carvacrol and eugenol) solubilized in nonionic surfactant micelles (surfynol 465 and 485w) was investigated. concentrations of encapsulated essential oil components ranged from 0.02 to 1.25% depending on compound, surfactant type, and surfactant concentration (0.5 to 5%). eugenol encapsulated in surfynol 485w micelles wa ... | 2005 | 16355826 |
| evaluation of detection methods for screening meat and poultry products for the presence of foodborne pathogens. | rapid and molecular technologies such as enzyme-linked immunosorbent assay (elisa), pcr, and lateral flow immunoprecipitation can reduce the time and labor involved in screening food products for the presence of pathogens. these technologies were compared with conventional culture methodology for the detection of salmonella, campylobacter, listeria, and escherichia coli o157:h7 inoculated in raw and processed meat and poultry products. recommended protocols were modified so that the same enrichm ... | 2005 | 16355836 |
| multicenter validation of a multiplex pcr assay for differentiating the major listeria monocytogenes serovars 1/2a, 1/2b, 1/2c, and 4b: toward an international standard. | the performance of a multiplex pcr assay that separates the four major serovars of the pathogenic listeria monocytogenes into four distinct pcr groups was evaluated through a multicenter typing study. identical panels of 90 listeria isolates were distributed to five participating laboratories that were blind to the nature of the isolates. isolates were characterized using the previously standardized protocol. overall concordance was 96.6 to 100%, sufficient for the assay to be used as an alterna ... | 2005 | 16355837 |
| adhesion of selected bifidobacterium strains to human intestinal mucus and the role of adhesion in enteropathogen exclusion. | the ability of potential probiotic strains to adhere to the intestinal mucosa and exclude and displace pathogens is of utmost importance for therapeutic manipulation of the enteric microbiota. the ability of seven selected human bifidobacterial strains and five human enteropathogenic strains to adhere to human intestinal mucus was analyzed and compared with that of four strains isolated from chicken intestines. the adhesion of the bifidobacterial strains ranged from 3 to 16% depending on the str ... | 2005 | 16355841 |
| subtyping listeria monocytogenes from bulk tank milk using automated repetitive element-based pcr. | sixty-one listeria monocytogenes strains from raw milk were analyzed with an automated repetitive element-based pcr (rep-pcr) system to examine the utility of this system for serotype grouping and to determine whether specific regional relationships could be identified. results of the similarity analysis revealed two primary clusters of l. monocytogenes isolates. cluster 2 exclusively contained serogroup 1/2a isolates; however, two 1/2a isolates were also found in cluster 1. isolates of serogrou ... | 2005 | 16355847 |
| listeria monocytogenes septic arthritis in a patient treated with etanercept for rheumatoid arthritis. | | 2005 | 16357718 |
| presentation of self-antigens on mhc class ii molecules during dendritic cell maturation. | little is known about how dendritic cells (dcs) maintain a balance between tolerance and immunity for antigens synthesized by dcs themselves. using transgenic dcs expressing a model self-antigen, in vitro self-peptide-mhc class ii complex formation and presentation increased with dc maturation, as for exogenous antigens. in vivo, however, even 'immature' dcs isolated from steady-state lymph nodes expressed mhc at mature cell levels, although many were also cd86 low. adoptive transfer of naive sp ... | 2006 | 16361313 |
| subversion of cellular functions by listeria monocytogenes. | listeria monocytogenes is a gram-positive bacterium that is able to invade and multiply within eukaryotic cells. its intracellular life-cycle includes pathogen-induced phagocytosis, lysis of the phagocytic vacuole, movement in the cytoplasmic environment, and a cell-to-cell spread mechanism. many l. monocytogenes virulence factors have been studied in detail, certain of which subvert specific eukaryotic cell functions in order to favour infection. during entry, the invasion protein inla takes ad ... | 2006 | 16362984 |
| listeria monocytogenes activated p38 mapk and induced il-8 secretion in a nucleotide-binding oligomerization domain 1-dependent manner in endothelial cells. | nucleotide-binding oligomerization domain (nod) proteins serve as intracellular pattern recognition molecules recognizing peptidoglycans. to further examine intracellular immune recognition, we used listeria monocytogenes as an organism particularly amenable for studying innate immunity to intracellular pathogens. in contrast to wild-type l. monocytogenes, the nonpathogenic listeria innocua, or l. monocytogenes mutants lacking internalin b or listeriolysin o, poorly invaded host cells and escape ... | 2006 | 16365441 |
| il-15 regulates cd8+ t cell contraction during primary infection. | during the course of acute infection with an intracellular pathogen, ag-specific t cells proliferate in the expansion phase, and then most of the t cells die by apoptosis in the following contraction phase, but the few that survive become memory cells and persist for a long period of time. although il-15 is known to play an important role in long-term maintenance of memory cd8+ t cells, the potential roles of il-15 in cd8+ t cell contraction are not known. using an adoptive transfer system of ot ... | 2006 | 16365444 |
| carbon metabolism of intracellular bacteria. | bacterial metabolism has been studied intensively since the first observations of these 'animalcules' by leeuwenhoek and their isolation in pure cultures by pasteur. metabolic studies have traditionally focused on a small number of model organisms, primarily the gram negative bacillus escherichia coli, adapted to artificial culture conditions in the laboratory. comparatively little is known about the physiology and metabolism of wild microorganisms living in their natural habitats. for approxima ... | 2006 | 16367862 |
| cytolysin-dependent delay of vacuole maturation in macrophages infected with listeria monocytogenes. | the bacterial pathogen listeria monocytogenes (lm) evades the antimicrobial mechanisms of macrophages by escaping from vacuoles to the cytosol, through the action of the cytolysin listeriolysin o (llo). because of heterogeneities in the timing and efficiency of escape, important questions about the contributions of llo to lm vacuole identity and trafficking have been inaccessible. expression of cyan fluorescent protein (cfp)-labelled endocytic membrane markers in macrophages along with a yellow ... | 2006 | 16367870 |
| identification of the insulin-like growth factor ii receptor as a novel receptor for binding and invasion by listeria monocytogenes. | the gram-positive bacterium listeria monocytogenes causes a life-threatening disease known as listeriosis. the mechanism by which l. monocytogenes invades mammalian cells is not fully understood, but the processes involved may provide targets to prevent and treat listeriosis. here, for the first time, we have identified the insulin-like growth factor ii receptor (igfiir; also known as the cation-independent mannose 6-phosphate receptor (ci)m6pr or cd222) as a novel receptor for binding and invas ... | 2006 | 16369013 |
| invasion of the placenta during murine listeriosis. | feto-placental infections due to listeria monocytogenes represent a major threat during pregnancy, and the underlying mechanisms of placental invasion remain poorly understood. here we used a murine model of listeriosis (pregnant mice, infected at day 14 of gestation) to investigate how this pathogen invades and grows within the placenta to ultimately infect the fetus. when l. monocytogenes is injected intravenously, the invasion of the placenta occurs early after the initial bacteremia, allowin ... | 2006 | 16369023 |
| listeria monocytogenes 10403s htra is necessary for resistance to cellular stress and virulence. | the htra serine protease has been shown to be essential for bacterial virulence and for survival after exposure to many types of environmental and cellular stresses. a listeria monocytogenes 10403s htra mutant was found to be sensitive to oxidative and puromycin-induced stress at high temperatures, showed a reduced ability to form biofilms, and was attenuated for virulence in mice. | 2006 | 16369036 |
| listeria spp. in the coastal environment of the aqaba gulf, suez gulf and the red sea. | listeria monocytogenes is an important pathogen which causes an infection called listeriosis. because of the high mortality rate (~30%) associated with listeriosis, and the widespread nature of the organism, it is a major concern for food and water microbiologists since it has been isolated from various types of foods, including seafood, as well as from the aqueous environment. to investigate the prevalence of this pathogen in the aqaba gulf (12 sites), suez gulf (14 sites) and red sea (14 sites ... | 2006 | 16371177 |
| lactobacillus plantarum inhibits growth of listeria monocytogenes in an in vitro continuous flow gut model, but promotes invasion of l. monocytogenes in the gut of gnotobiotic rats. | the ability of the pediocin ach producing lactobacillus plantarum dden 11007 and its non-producing plasmid-cured isogenic variant, dden 12305 to prevent the persistence and growth of listeria monocytogenes ep2 in two gastrointestinal (gi) tract models was examined. in vitro studies conducted in a two-stage continuous flow system showed that l. plantarum dden 11007 inhibited l. monocytogenes ep2 under these conditions, while less effect was seen of the non-bacteriocin producing variant. the inhib ... | 2006 | 16376449 |
| leger: knowledge database and visualization tool for comparative genomics of pathogenic and non-pathogenic listeria species. | listeria species are ubiquitous in the environment and often contaminate foods because they grow under conditions used for food preservation. listeria monocytogenes, the human and animal pathogen, causes listeriosis, an infection with a high mortality rate in risk groups such as immune-compromised individuals. furthermore, l.monocytogenes is a model organism for the study of intracellular bacterial pathogens. the publication of its genome sequence and that of the non-pathogenic species listeria ... | 2006 | 16381897 |
| the streptococcal blr and slr proteins define a family of surface proteins with leucine-rich repeats: camouflaging by other surface structures. | regions with tandemly arranged leucine-rich repeats (lrrs) have been found in many prokaryotic and eukaryotic proteins, in which they provide a remarkably versatile framework for the formation of ligand-binding sites. bacterial lrr proteins include the recently described slr protein of streptococcus pyogenes, which is related to internalin a of listeria monocytogenes. here, we show that strains of the human pathogen streptococcus agalactiae express a protein, designated blr, which together with ... | 2006 | 16385027 |
| identification of listeria monocytogenes genes contributing to intracellular replication by expression profiling and mutant screening. | a successful transition of listeria monocytogenes from the extracellular to the intracellular environment requires a precise adaptation response to conditions encountered in the host milieu. although many key steps in the intracellular lifestyle of this gram-positive pathogen are well characterized, our knowledge about the factors required for cytosolic proliferation is still rather limited. we used dna microarray and real-time reverse transcriptase pcr analyses to investigate the transcriptiona ... | 2006 | 16385046 |
| central nervous system tumor immunity generated by a recombinant listeria monocytogenes vaccine targeting tyrosinase related protein-2 and real-time imaging of intracranial tumor burden. | previously, we demonstrated that a recombinant listeria monocytogenes (rlm) vector encoding the melanoma-associated antigen, tyrosinase related protein (trp)-2, could successfully treat subcutaneous b16 melanomas. the purpose of the present study was twofold: 1) to test whether this rlm-nucleoprotein (np)/trp-2 could generate antitumor immunity to a b16 tumor challenge in the immunologically privileged central nervous system (cns) and 2) to develop a noninvasive imaging modality to monitor tumor ... | 2006 | 16385341 |
| antilisterial activity of grape juice and grape extracts derived from vitis vinifera variety ribier. | grape juice and skin and seed extracts of vitis vinifera var. ribier black table grapes were found to be highly inhibitory towards listeria monocytogenes. this grape juice was also active against all other listeria species tested but not against bacillus cereus, salmonella menston, escherichia coli, staphylococcus aureus or yersinia enterocolitica. fractionation of the extracts showed that the antilisterial activity was strongest in the polymeric phenolic fractions. two different types of active ... | 2006 | 16386816 |
| control of listeria monocytogenes in raw-milk cheeses. | the development of listeria monocytogenes in cheeses made with raw-milk originating from six different farms and according to the saint-nectaire cheesemaking technology was studied. milk was inoculated with two strains of l. monocytogenes at 5 to 10 cfu/25 ml. microbial and chemical analyses were carried out at appropriate intervals during ripening. l. monocytogenes did not grow in the cores of cheeses prepared with milk originating from three farms. that inhibition could be partially attributed ... | 2006 | 16386817 |
| structural basis for metal binding specificity: the n-terminal cadmium binding domain of the p1-type atpase cada. | in bacteria, p1-type atpases are responsible for resistance to di- and monovalent toxic heavy metals by taking them out of the cell. these atpases have a cytoplasmic n terminus comprising metal binding domains defined by a betaalphabetabetaalphabeta fold and a cxxc metal binding motif. to check how the structural properties of the metal binding site in the n terminus can influence the metal specificity of the atpase, the first structure of a cd(ii)-atpase n terminus was determined by nmr and its ... | 2006 | 16388822 |
| a spontaneous genomic deletion in listeria ivanovii identifies lipi-2, a species-specific pathogenicity island encoding sphingomyelinase and numerous internalins. | listeria ivanovii differs from the human pathogen listeria monocytogenes in that it specifically affects ruminants, causing septicaemia and abortion but not meningo-encephalitis. the genetic characterization of spontaneous l. ivanovii mutants lacking the virulence factor smcl (sphingomyelinase) led us to identify lipi-2, the first species-specific pathogenicity island from listeria. besides smcl, this 22 kb chromosomal locus encodes 10 internalin (inl) proteins: i-inlb1 and -b2 are large/surface ... | 2006 | 16390439 |
| listeriosis in pregnancy: a case report. | listeria monocytogenes is an alimentary infection which can be extremely dangerous for pregnant women. a 34-year-old pregnant woman was hospitalized with fetal cardiac rate alterations and influenza-like symptoms. a caesarean section due to fetal distress was performed. a maternal-fetal listeriosis diagnosis was possible only after the birth through bacteriological and histological examination on both the placenta and the newborn. | 2005 | 16390801 |
| listeria monocytogenes serotype 4b strains belonging to lineages i and iii possess distinct molecular features. | a collection of listeria monocytogenes serotype 4b strains belonging to lineages i and iii were examined by pcr and southern blot analysis using species-, virulence-, and serotype-specific primers and probes. whereas four serotype 4b lineage i strains reacted in pcr with the serotype 4b-, 4d-, and 4e-specific orf2110 and virulence-specific lmo1134 and lmo2821 primers, all nine serotype 4b lineage iii strains were negative by orf2110 and lmo1134 primers. in addition, the nine serotype 4b lineage ... | 2006 | 16390972 |
| fourier transform infrared and raman spectroscopy for characterization of listeria monocytogenes strains. | the purpose of this study was to characterize the variation in biochemical composition of 89 strains of listeria monocytogenes with different susceptibilities towards sakacin p, using fourier transform infrared (ftir) spectroscopy and raman spectroscopy. the strains were also analyzed using amplified fragment length polymorphism (aflp) analysis. based on their susceptibilities to sakacin p, the 89 strains have previously been divided into two groups. using the ftir spectra and aflp data, the str ... | 2006 | 16391047 |
| inhibition of listeria monocytogenes by food-borne yeasts. | many bacteria are known to inhibit food pathogens, such as listeria monocytogenes, by secreting a variety of bactericidal and bacteriostatic substances. in sharp contrast, it is unknown whether yeast has an inhibitory potential for the growth of pathogenic bacteria in food. a total of 404 yeasts were screened for inhibitory activity against five listeria monocytogenes strains. three hundred and four of these yeasts were isolated from smear-ripened cheeses. most of the yeasts were identified by f ... | 2006 | 16391059 |
| persistence of mycobacterium avium subsp. paratuberculosis and other zoonotic pathogens during simulated composting, manure packing, and liquid storage of dairy manure. | livestock manures contain numerous microorganisms which can infect humans and/or animals, such as escherichia coli o157:h7, listeria monocytogenes, salmonella spp., and mycobacterium avium subsp. paratuberculosis (mycobacterium paratuberculosis). the effects of commonly used manure treatments on the persistence of these pathogens have rarely been compared. the objective of this study was to compare the persistence of artificially inoculated m. paratuberculosis, as well as other naturally occurri ... | 2006 | 16391093 |
| competitive fitness of listeria monocytogenes serotype 1/2a and 4b strains in mixed cultures with and without food in the u.s. food and drug administration enrichment protocol. | thirteen different serotypes of the food-borne pathogen listeria monocytogenes have been described. serotype 4b strains are most often associated with illness, and serotype 1/2a strains are most often isolated from foods and processing plants. different abilities to respond to stresses have been described for serotype 4b and 1/2a strains. one of the common enrichment protocols used to test foods for the presence l. monocytogenes is described in the u.s. food and drug administration (fda) bacteri ... | 2006 | 16391118 |
| listeria monocytogenes listeriolysin o and phosphatidylinositol-specific phospholipase c affect adherence to epithelial cells. | listeria monocytogenes, a foodborn intracellular animal and human pathogen, produces several exotoxins contributing to virulence. among these are listeriolysin o (llo), a pore-forming cholesterol-dependent hemolysin, and a phosphatidylinositol-specific phospholipase c (pi-plc). llo is known to play an important role in the escape of bacteria from the primary phagocytic vacuole of macrophages, and pi-plc supports this process. evidence is accumulating that llo and pi-plc are multifunctional virul ... | 2005 | 16391652 |
| tnf receptor type 2 (p75) functions as a costimulator for antigen-driven t cell responses in vivo. | naive t cells require costimulation for robust ag-driven differentiation and survival. members of the tnfr family have been shown to provide costimulatory signals conferring survival at distinct phases of the t cell response. in this study, we show that cd4 and cd8 t cells depend on tnfr type 2 (p75) for survival during clonal expansion, allowing larger accumulation of effector cells and conferring protection from apoptosis for a robust memory pool in vivo. we demonstrate using the mhc class i-r ... | 2006 | 16393990 |
| bovine peptidoglycan recognition protein-s: antimicrobial activity, localization, secretion, and binding properties. | peptidoglycan (pgn) recognition proteins (pgrps) are pattern recognition molecules of innate immunity that are conserved from insects to humans. various pgrps are reported to have diverse functions: they bind bacterial molecules, digest pgn, and are essential to the toll pathway in drosophila. one family member, bovine pgn recognition protein-s (bpgrp-s), has been found to bind and kill microorganisms in a pgn-independent manner, raising questions about the identity of the bpgrp-s ligand. addres ... | 2006 | 16394004 |
| trimethoprim-sulfamethoxazole-induced aseptic meningitis. | we present a 46-year-old african-american man with aids who was admitted on two different occasions within three weeks for signs and symptoms of meningitis after using trimethoprim/sulfamethoxazole (tmp/smx). tmp/smx is primarily used for the treatment of pneumocystis carinii pneumonia prophylaxis in aids patients. drug-induced aseptic meningitis (diam) is commonly seen with nonsteroidal anti-inflammatory drugs (nsaids), antibiotics (with tmp/smx being the most frequently implicated), intravenou ... | 2005 | 16396068 |
| solid-phase synthesis of polyfunctionalized natural products: application to usnic acid, a bioactive lichen compound. | | 2006 | 16398547 |
| fosfomycin resistance proteins: a nexus of glutathione transferases and epoxide hydrolases in a metalloenzyme superfamily. | three similar but mechanistically distinct fosfomycin resistance proteins that catalyze the opening of the oxirane ring of the antibiotic are known. fosa is a mn(ii) and k(+)-dependent glutathione transferase. fosb is a mg(2+)-dependent l-cysteine thiol transferase. fosx is a mn(ii)-dependent fosfomycin-specific epoxide hydrolase. the expression, purification, kinetic, and physical characteristics of six fosfomycin resistance proteins including the fosa proteins from transposon tn2921 and pseudo ... | 2005 | 16399398 |
| [neurolisteriosis in adults: report of six clinical cases]. | listeria monocytogenes shows a special attraction to infect the central nervous system and its meningeals coats. it affects newborn as well as elderly people, patients with deficiencies in their cellular immune systems, and healthy adults. it presents most commonly as an acute meningitis, although it can present itself as cerebritis, brain stem encephalitis (rhomboencephalitis), and exceptionally as myelitis. | 2005 | 16400430 |
| bloodstream infections in organ transplant recipients receiving alemtuzumab: no evidence of occurrence of organisms typically associated with profound t cell depletion. | alemtuzumab is a humanized monoclonal antibody directed against cd52, a cell surface antigen expressed on b and t lymphocytes, monocytes and nk cells. its use results in a profound decrease in cd4 positive t lymphocytes. alemtuzumab is used as induction immunosuppression and therapy for rejection in organ transplant recipients in some centers. we followed a cohort of 449 consecutive transplant recipients who received alemtuzumab to determine the occurrence of bloodstream infections, particularly ... | 2006 | 16403576 |
| respiratory infection of turkeys with listeria monocytogenes scott a. | the pathogenesis of l. monocytogenes strain scott a was studied by challenging day-old male turkey poults by air sac inoculation with tryptose phosphate broth containing 10(0) cfu (control), 10(4), 10(5), and 10(6) cfu (low challenge), or 10(7) and 10(8) cfu (high challenge) of the scott a (serotype 4b) strain of l. monocytogenes. mortality at 2 wk postinfection (pi) ranged from 25% for low challenge to 100% for high challenge (p= 0.0001). gross and histopathological lesions were observed in hea ... | 2005 | 16404998 |
| therapy of paraneoplastic pemphigus with rituximab: a case report and review of literature. | paraneoplastic pemphigus (pnp) is an autoimmune blistering disease with poor prognosis when associated with malignant neoplasm. we report the case of a patient with pnp associated with a cd20+ non-hodgkin follicular lymphoma who was treated with rituximab plus corticosteroids and short courses of cyclosporin. one and a half years after rituximab therapy, oral ulcerations had cleared and oral methylprednisolone was slowly tapered down without further recurrences. in the course of the disease, the ... | 2006 | 16405612 |
| multiple characterizations of listeria monocytogenes sensitive and insensitive variants to divergicin m35, a new pediocin-like bacteriocin. | divergicin m35 is a new class iia bacteriocin produced by carnobacterium divergicin m35. the bactericidal activity of this antimicrobial peptide was tested against a set of 11 strains of listeria monocytogenes isolated from food. | 2006 | 16405682 |
| partial characterization of enterocin mr99 from a corn silage isolate of enterococcus faecalis. | to assess the inhibitory activity on gram-positive and gram-negative bacteria of several species of enterococci recovered from a natural corn silage. | 2006 | 16405692 |
| evaluation of live-culture-producing lacticin 3147 as a treatment for the control of listeria monocytogenes on the surface of smear-ripened cheese. | a live lactococcus lactis culture, producing the two-component broad spectrum bacteriocin lacticin 3147, was assessed for ability to inhibit the food pathogen listeria monocytogenes on the surface of smear-ripened cheese. | 2006 | 16405693 |
| bacterial rna and small antiviral compounds activate caspase-1 through cryopyrin/nalp3. | missense mutations in the cias1 gene cause three autoinflammatory disorders: familial cold autoinflammatory syndrome, muckle-wells syndrome and neonatal-onset multiple-system inflammatory disease. cryopyrin (also called nalp3), the product of cias1, is a member of the nod-lrr protein family that has been linked to the activation of intracellular host defence signalling pathways. cryopyrin forms a multi-protein complex termed 'the inflammasome', which contains the apoptosis-associated speck-like ... | 2006 | 16407888 |
| cryopyrin activates the inflammasome in response to toxins and atp. | a crucial part of the innate immune response is the assembly of the inflammasome, a cytosolic complex of proteins that activates caspase-1 to process the proinflammatory cytokines interleukin (il)-1beta and il-18. the adaptor protein asc is essential for inflammasome function, binding directly to caspase-1 (refs 3, 4), but the triggers of this interaction are less clear. asc also interacts with the adaptor cryopyrin (also known as nalp3 or cias1). activating mutations in cryopyrin are associated ... | 2006 | 16407890 |
| invasion assay of listeria monocytogenes using vero and caco-2 cells. | the invasion ability of listeria monocytogenes into cultured cells has been used to evaluate its pathogenicity. in this study, invasive ability was investigated using vero and caco-2 cell lines. the form of invasion showed no morphological differences between both cell lines inoculated with l. monocytogenes l89-h2 or l96-23c1 strains when double fluorescence stained with rhodamine and fitc or with giemsa staining. recovery count and recovery rate of l. monocytogenes from vero cells was related t ... | 2006 | 16410027 |
| detection and quantification of listeria monocytogenes by 5'-nuclease polymerase chain reaction targeting the acta gene. | the aim of this study was to develop a 5'-nuclease polymerase chain reaction (pcr) for the rapid detection and quantification of listeria monocytogenes. | 2006 | 16411913 |
| ultrastructural studies on antimicrobial efficacy of thyme essential oils on listeria monocytogenes. | listeria monocytogenes has gained increasing attention as a pathogen of public health importance owing to large numbers of food-borne outbreaks of listeriosis. because of negative consumer perception of chemical preservatives, attention is shifting towards natural alternatives. particular interest has been focused on the potential application of plant essential oils. the objective of the present study was to determine ultrastructural changes brought about by essential oils from two types of thym ... | 2006 | 16412677 |
| recognition of cytosolic dna activates an irf3-dependent innate immune response. | nucleic acid recognition upon viral infection triggers type i interferon production. viral rna is detected by both endosomal, tlr-dependent and cytosolic, rig-i/mda5-dependent pathways. tlr9 is the only known sensor of foreign dna; it is unknown whether innate immune recognition of dna exists in the cytosol. here we present evidence that cytosolic dna activates a potent type i interferon response to the invasive bacterium listeria monocytogenes. the noninvasive legionella pneumophila triggers an ... | 2006 | 16413926 |
| how seryl-phosphorylated hpr inhibits prfa, a transcription activator of listeria monocytogenes virulence genes. | listeria monocytogenes prfa, a transcription activator for several virulence genes, including the hemolysin-encoding hly, is inhibited by rapidly metabolizable carbon sources (glucose, fructose, etc.). this inhibition is not mediated via the major carbon catabolite repression mechanism of gram-positive bacteria, since inactivation of the catabolite control protein a (ccpa) did not prevent the repression of virulence genes by the above sugars. in order to test whether the catabolite co-repressor ... | 2005 | 16415595 |
| actin-dependent movement of bacterial pathogens. | listeria, rickettsia, burkholderia, shigella and mycobacterium species subvert cellular actin dynamics to facilitate their movement within the host cytosol and to infect neighbouring cells while evading host immune surveillance and promoting their intracellular survival. 'attaching and effacing' escherichia coli do not enter host cells but attach intimately to the cell surface, inducing motile actin-rich pedestals, the function of which is currently unclear. the molecular basis of actin-based mo ... | 2006 | 16415925 |
| hot water postprocess pasteurization of cook-in-bag turkey breast treated with and without potassium lactate and sodium diacetate and acidified sodium chlorite for control of listeria monocytogenes. | surface pasteurization and food-grade chemicals were evaluated for the ability to control listeriae postprocess on cook-in-bag turkey breasts (cibtb). individual cibtb were obtained directly from a commercial manufacturer and surface inoculated (20 ml) with a five-strain cocktail (ca. 7.0 log) of listeria innocua. in each of two trials, the product was showered or submerged for up to 9 min with water heated to 190, 197, or 205 degrees f (ca. 87.8, 91.7, or 96.1 degrees c) in a commercial pasteur ... | 2006 | 16416899 |
| combining organic acid treatment with steam pasteurization to eliminate listeria monocytogenes on fully cooked frankfurters. | an organic acid solution of 2% acetic, 1% lactic, 0.1% propionic, and 0.1% benzoic acids was combined with steam surface pasteurization to treat frankfurters during vacuum packaging to eliminate potential postcook contamination with listeria monocytogenes. the thermal lethality of l. monocytogenes from steam was evaluated at an inoculation concentration of 1 to 6 log cfu/cm2. about 3-log reductions of l. monocytogenes were achieved when frankfurters were treated by steam for 1.5 s. combining org ... | 2006 | 16416900 |
| post process control of listeria monocytogenes on commercial frankfurters formulated with and without antimicrobials and stored at 10 degrees c. | the antilisterial effect of postprocess antimicrobial treatments on commercially manufactured frankfurters formulated with and without a 1.5% potassium lactate-0.05% sodium diacetate combination was evaluated. frankfurters were inoculated (ca. 3 to 4 log cfu/cm2) with 10-strain composite listeria monocytogenes cultures originating from different sources. the inocula evaluated were cells grown planktonically in tryptic soy broth plus 0.6% yeast extract (30 degrees c, 24 h) or in a smoked sausage ... | 2006 | 16416901 |
| a predictive model for the effect of temperature and predrying treatments in reducing listeria monocytogenes populations during drying of beef jerky. | the objective of this study was to model the effect of drying temperatures (52, 57, and 63 degrees c) and predrying treatments on the inactivation of listeria monocytogenes on beef jerky. before drying, beef slices were inoculated with a 10-strain composite of l. monocytogenes and then treated with the following: (i) nothing (c), (ii) traditional marinade (m), or (iii) dipping in 5% acetic acid solution for 10 min, followed by m (am). in addition, sequential stresses (exposure to 10% nacl, follo ... | 2006 | 16416902 |
| cross-contamination between processing equipment and deli meats by listeria monocytogenes. | contamination of luncheon meats by listeria monocytogenes has resulted in outbreaks of listeriosis and major product recalls. listeriae can survive on processing equipment such as meat slicers which serve as a potential contamination source. this study was conducted to determine (i) the dynamics of cross-contamination of l. monocytogenes from a commercial slicer and associated equipment onto sliced meat products, (ii) the influence of sample size on the efficacy of the bax-pcr and u.s. departmen ... | 2006 | 16416903 |
| molecular characterization of listeria monocytogenes from natural and urban environments. | characterization of 80 listeria monocytogenes isolates from urban and natural environments differentiated 7 and 26 ecori ribotypes, respectively. whereas the majority of isolates from the natural environment represented l. monocytogenes lineage ii (12 of 13 isolates), urban isolates grouped evenly into lineages i and ii (32 and 33 isolates, respectively) and included two lineage iii isolates. multilocus sequence typing of all natural isolates and a randomly selected subset of 30 urban isolates s ... | 2006 | 16416906 |
| sensitivities of foodborne pathogens to pressure changes. | eight foodborne pathogens were suspended in ultrahigh-temperature whole milk and treated at pressure levels of 0.1 to 690 mpa at 21.5 degrees c for 10 min. there was no clear trend in pressure resistance between gram-negative and gram-positive organisms. the order of the single strains tested, from most to least pressure sensitive, was vibrio parahaemolyticus < yersinia enterocolitica < listeria monocytogenes < salmonella enterica serovar typhimurium < s. enterica serovar enteritidis < escherich ... | 2006 | 16416910 |
| influence of antimicrobial compounds and modified atmosphere packaging on radiation sensitivity of listeria monocytogenes present in ready-to-use carrots (daucus carota). | radiosensitization of listeria monocytogenes was determined in the presence of trans-cinnamaldehyde, spanish oregano, winter savory, and chinese cinnamon on peeled minicarrots packed under air or under a modified atmosphere (60% o2, 30% co2, and 10% n2). samples were inoculated with l. monocytogenes hpb 2812 serovar 1/2a (106 cfu/g) and were coated separately with each active compound (0.5%, wt/wt) before being packaged under air or the modified atmosphere and irradiated at doses from 0.07 to 2. ... | 2006 | 16416924 |
| wasp family proteins act between cytoskeleton and cellular signaling pathways. | this review considers the proteins of the wasp (wiskott-aldrich syndrome protein) family and their role in the regulation of actin-based motility. it contains detailed classification of the wasp family proteins and data on their subcellular localization. impairments of expression of the wasp family proteins cause certain cell pathologies. the review also deals with domain organization of these proteins and proteins interacting with various domains of the wasp proteins. special attention is given ... | 2005 | 16417451 |
| disruption of escherichia coli, listeria monocytogenes and lactobacillus sakei cellular membranes by plant oil aromatics. | the role of membrane disruption in the bactericidal activity of the plant oil aromatic compounds eugenol, carvacrol and cinnamaldehyde was investigated using confocal laser scanning microscopy, changes in atp levels and cell viability. in 25 mm hepes buffer ph 7 at 20 degrees c, 10 mm eugenol or carvacrol increased uptake of propidium iodide by escherichia coli, listeria monocytogenes and lactobacillus sakei over a 10-min period. the same treatments resulted in lowered viability, rapid depletion ... | 2006 | 16417936 |
| [endocarditis due to listeria monocytogenes associated with aortic stenosis]. | | 2005 | 16419604 |
| listeria monocytogenes as a probe of immune function. | for almost half a century, the mouse model of listeria monocytogenes infection has been used to analyse both innate and adaptive components of immunity and to discover key immune genes. vast accumulated knowledge about the disease in mice provides a unique framework for identifying and characterising immune molecules using a variety of experimental approaches. to illustrate the range of questions that can be addressed using modern genetics and genomics tools, the authors provide an overview of t ... | 2005 | 16420751 |
| selective targeting of antitumor immune responses with engineered live-attenuated listeria monocytogenes. | improved immunization and ex vivo t-cell culture strategies can generate larger numbers and more potent tumor-specific effector cells than previously possible. nonetheless, the capacity of these cells to eliminate established tumors is limited by their ability to efficiently enter tumor-bearing organs and mediate their effector function. in the current study, we show that the administration of an engineered organ-homing microbe selectively targets tumor-specific immune responses to metastases wi ... | 2006 | 16424046 |
| cutting edge: a novel nonoxidative phagosomal mechanism exerted by cathepsin-d controls listeria monocytogenes intracellular growth. | deciphering how listeria monocytogenes exploits the host cell machinery to invade mammalian cells is a key issue in understanding the pathogenesis of this food-borne pathogen, which can cause diseases ranging from gastroenteritis to meningitis and abortion. in this study, we show that the lysosomal aspartyl-protease cathepsin-d (ctsd) is of considerable importance for nonoxidative listericidal defense mechanisms. we observed enhanced susceptibility to l. monocytogenes infection of fibroblasts an ... | 2006 | 16424157 |
| protein vaccines induce uncommitted il-2-secreting human and mouse cd4 t cells, whereas infections induce more ifn-gamma-secreting cells. | mouse and human cd4 t cells primed during an immune response may differentiate into effector phenotypes such as th1 (secreting ifn-gamma) or th2 (secreting il-4) that mediate effective immunity against different classes of pathogen. however, primed cd4 t cells can also remain uncommitted, secreting il-2 and chemokines, but not ifn-gamma or il-4. we now show that human cd4 t cells primed by protein vaccines mostly secreted il-2, but not ifn-gamma, whereas in the same individuals most cd4 t cells ... | 2006 | 16424174 |
| sigma b contributes to listeria monocytogenes gastrointestinal infection but not to systemic spread in the guinea pig infection model. | contributions of the alternative sigma factor sigmab to listeria monocytogenes infection were investigated using strains bearing null mutations in sigb, prfa, or inla or in selected inla or prfa promoter regions. the deltap4inla strain, which has a deletion in the sigmab-dependent p4inla promoter, and the deltasigb strain had significantly reduced invasion efficiencies relative to that of the wild-type strain in the caco-2 human colorectal epithelial cell line, while the invasion efficiency of a ... | 2006 | 16428730 |
| identification of novel gammadelta t-cell subsets following bacterial infection in the absence of vgamma1+ t cells: homeostatic control of gammadelta t-cell responses to pathogen infection by vgamma1+ t cells. | although gammadelta t cells are a common feature of many pathogen-induced immune responses, the factors that influence, promote, or regulate the response of individual gammadelta t-cell subsets to infection is unknown. here we show that in the absence of vgamma1+ t cells, novel subsets of gammadelta t cells, expressing t-cell receptor (tcr)-vgamma chains that normally define tcrgammadelta+ dendritic epidermal t cells (detcs) (vgamma5+), intestinal intraepithelial lymphocytes (iiels) (vgamma7+), ... | 2006 | 16428757 |
| intracellular gene expression profile of listeria monocytogenes. | listeria monocytogenes is a gram-positive, food-borne microorganism responsible for invasive infections with a high overall mortality. l. monocytogenes is among the very few microorganisms that can induce uptake into the host cell and subsequently enter the host cell cytosol by breaching the vacuolar membrane. we infected the murine macrophage cell line p388d1 with l. monocytogenes strain egd-e and examined the gene expression profile of l. monocytogenes inside the vacuolar and cytosolic environ ... | 2006 | 16428782 |
| development of a magnetic capture hybridization-pcr assay for listeria monocytogenes direct detection in milk samples. | a rapid and sensitive method for listeria monocytogenes direct detection from milk was developed. it is based on a magnetic capture hybridization procedure for selective dna purification, followed by pcr identification. a comparison with two similar commercial systems from dynal (dynabeads) was carried out. | 2006 | 16430514 |
| iron acquisition systems for ferric hydroxamates, haemin and haemoglobin in listeria monocytogenes. | listeria monocytogenes is a gram-positive bacterium that causes severe opportunistic infections in humans and animals. we biochemically characterized, for the first time, the iron uptake processes of this facultative intracellular pathogen, and identified the genetic loci encoding two of its membrane iron transporters. strain egd-e used iron complexes of hydroxamates (ferrichrome and ferrichrome a, ferrioxamine b), catecholates (ferric enterobactin, ferric corynebactin) and eukaryotic binding pr ... | 2006 | 16430693 |
| mechanism of polarization of listeria monocytogenes surface protein acta. | the polar distribution of the acta protein on the surface of the gram-positive intracellular bacterial pathogen, listeria monocytogenes, is required for bacterial actin-based motility and successful infection. acta spans both the bacterial membrane and the peptidoglycan cell wall. we have directly examined the de novo acta polarization process in vitro by using an acta-rfp (red fluorescent protein) fusion. after induction of expression, acta initially appeared at distinct sites along the sides o ... | 2006 | 16430699 |
| antimicrobial spectrum and potency of dalbavancin tested against clinical isolates from europe and north america (2003): initial results from an international surveillance protocol. | dalbavancin is a bactericidal dimethylaminopropyl amide glycopeptide derivative possessing an extended serum elimination half-life in humans that allows once-weekly dosing for the therapy of gram-positive infections. strains from this baseline surveillance protocol in north america (na; usa and canada) and europe (eu, 14 countries) were sampled in 2003. a total of 7,765 gram-positive isolates (3,695 from na and 4,070 from eu) were tested by reference broth microdilution methods against dalbavanc ... | 2005 | 16433188 |
| detection and identification of intestinal pathogenic bacteria by hybridization to oligonucleotide microarrays. | to detect the common intestinal pathogenic bacteria quickly and accurately. | 2005 | 16437687 |
| [neonatal infection with listeria monocytogenes: rare, but serious]. | between 1993 and 2003, three infants, two girls and a boy, were found to have an invasive infection with listeria monocytogenes. they received intensive care including respiratory and circulatory support, antibiotics, and treatment of the neurological complications when possible. one of the girls survived without sequelae but the other two infants died in the neonatal period. in one of these two cases there was a clear clue to the source of the infection in the dietary history of the mother: she ... | 2006 | 16440567 |
| phosphorylation, ubiquitination and degradation of listeriolysin o in mammalian cells: role of the pest-like sequence. | listeria monocytogenes is a bacterial pathogen that grows within the cytosol of infected host cells. entry into the cytosol is largely mediated by a secreted bacterial cytolysin, listeriolysin o (llo). in order to prevent host cell damage, the pore-forming activity of llo is restricted to the phagosome. compartmentalization of llo requires a pest-like sequence; pest sequences can direct eukaryotic proteins for proteasomal degradation. here we test the hypothesis that llo's pest-like sequence com ... | 2006 | 16441444 |
| listeria monocytogenes in platelets: a case report. | efforts to reduce bacterial contamination in platelets (plts) have led to implementation of tests for bacterial detection before product release. although relatively rare as a human pathogen, listeria monocytogenes often causes serious illness and has a case-fatality rate of 20 percent. | 2006 | 16441611 |
| interferon-producing killer dendritic cells provide a link between innate and adaptive immunity. | natural killer (nk) cells and dendritic cells (dcs) are, respectively, central components of innate and adaptive immune responses. we describe here a third dc lineage, termed interferon-producing killer dcs (ikdcs), distinct from conventional dcs and plasmacytoid dcs and with the molecular expression profile of both nk cells and dcs. they produce substantial amounts of type i interferons (ifn) and interleukin (il)-12 or ifn-gamma, depending on activation stimuli. upon stimulation with cpg oligod ... | 2006 | 16444266 |
| allelic exchange and site-directed mutagenesis probe the contribution of acta amino-acid variability to phosphorylation and virulence-associated phenotypes among listeria monocytogenes strains. | to test the hypothesis that acta allelic variation contributes to virulence differences among listeria monocytogenes strains, cell-to-cell spread and intracellular acta phosphorylation patterns were characterized for 14 wild-type isolates and selected isogenic mutants. our data show that (i) while acta allelic variation is not responsible for enhanced cell-to-cell spread observed in epidemic clone i strains, acta allelic variation may contribute to reduced plaque size observed in some isolates, ... | 2006 | 16445760 |
| listeria monocytogenes invades the epithelial junctions at sites of cell extrusion. | listeria monocytogenes causes invasive disease by crossing the intestinal epithelial barrier. this process depends on the interaction between the bacterial surface protein internalin a and the host protein e-cadherin, located below the epithelial tight junctions at the lateral cell-to-cell contacts. we used polarized mdck cells as a model epithelium to determine how l. monocytogenes breaches the tight junctions to gain access to this basolateral receptor protein. we determined that l. monocytoge ... | 2006 | 16446782 |
| susceptibility to mycobacterial infections due to interferon-gamma and interleukin-12 pathway defects. | a case of interferon-gamma (ifn-gamma)/interleukin-12 (il-12) pathway defect is presented. pathophysiology, clinical characteristics, diagnostic test, and case management are reviewed. clinical pearls and pitfalls include: (1) a high probability of a defect in the ifn-gamma/il-12 cascade exists in patients with disseminated or recurrent infection due to poorly pathogenic mycobacteria or systemic infections caused by non-typhi salmonella species that are persistent and recurrent despite antibioti ... | 2005 | 16450579 |
| ladr, a new padr-related transcriptional regulator from listeria monocytogenes, negatively regulates the expression of the multidrug efflux pump mdrl. | the listeria monocytogenes genome encodes putative multidrug efflux transporters but only the mdrl transporter has been partially characterized in the wild-type lo28 strain. here, we show in the lo28 strain, that the expression of mdrl is repressed at the transcriptional level, under standard growth conditions, by the product of a new gene ladr (lmo1408), and the expression of mdrl is induced in the presence of rhodamine. phylogenetic analysis in related firmicutes shows that ladr, conserved in ... | 2006 | 16451184 |
| liposome-doped nanocomposites as artificial-cell-based biosensors: detection of listeriolysin o. | listeriolysin o (llo) is a pore-forming hemolysin secreted by the foodborne pathogen listeria monocytogenes and is required for bacterial virulence. current detection methods for l. monocytogenes are time-consuming, labor-intensive, and expensive, which is impractical considering the limitations of food storage. to overcome these problems, we developed a liposome-doped silica nanocomposite as a simple, inexpensive, and highly stable biosensor material that mimics existing whole-cell assays for l ... | 2006 | 16454489 |
| the wild-derived inbred mouse strain spret/ei is resistant to lps and defective in ifn-beta production. | although activation of toll-like receptor 4 (tlr4)-positive cells is essential for eliminating gram-negative bacteria, overactivation of these cells by the tlr4 ligand lps initiates a systemic inflammatory reaction and shock. here we demonstrate that spret/ei mice, derived from mus spretus, exhibit a dominant resistance against lps-induced lethality. this resistance is mediated by bone marrow-derived cells. macrophages from these mice exhibit normal signaling and gene expression responses that d ... | 2006 | 16455798 |
| production, characterisation and potential application of a novel monoclonal antibody for rapid identification of virulent listeria monocytogenes. | a panel of hybridomas was produced using intact listeria monocytogenes serotype 1/2a cells as the immunogen. an igg2a monoclonal antibody (mab) 'mab2b3' was isolated that reacted with l. monocytogenes but not with a representative panel of related listeria spp. and non-listeria spp. binding activity was greatest against l. monocytogenes serotype 1/2a and was significantly enhanced when cells were prepared in listeria enrichment broth (leb). the reactive epitope was deduced, by immunoblot analysi ... | 2006 | 16457899 |
| patho-biotechnology: using bad bugs to do good things. | pathogenic bacteria have evolved sophisticated strategies to overcome host defences, to interact with the immune system and to interfere with essential host systems. we coin the term 'patho-biotechnology' to describe the exploitation of these valuable traits in biotechnology, medicine and food. this approach shows promise for the development of novel vaccine and drug delivery systems, as well as for the design of more technologically robust and effective probiotic cultures with improved biotechn ... | 2006 | 16459072 |
| h2-m3-restricted cd8+ t cells are not required for mhc class ib-restricted immunity against listeria monocytogenes. | studies using major histocompatibility complex (mhc)-ia-deficient mice have shown that mhc-ib-restricted cd8+ t cells can clear infections caused by intracellular pathogens such as listeria monocytogenes. m3-restricted cd8+ t cells, which recognize short hydrophobic n-formylated peptides, appear to comprise a substantial portion of the mhc-ib-restricted t cell response in the mouse model of l. monocytogenes infection. in this study, we isolated formyltransferase (fmt) mutant strains of l. monocy ... | 2006 | 16461341 |
| reliable and rapid identification of listeria monocytogenes and listeria species by artificial neural network-based fourier transform infrared spectroscopy. | differentiation of the species within the genus listeria is important for the food industry but only a few reliable methods are available so far. while a number of studies have used fourier transform infrared (ftir) spectroscopy to identify bacteria, the extraction of complex pattern information from the infrared spectra remains difficult. here, we apply artificial neural network technology (ann), which is an advanced multivariate data-processing method of pattern analysis, to identify listeria ... | 2006 | 16461640 |
| biocontrol of the food-borne pathogens listeria monocytogenes and salmonella enterica serovar poona on fresh-cut apples with naturally occurring bacterial and yeast antagonists. | fresh-cut apples contaminated with either listeria monocytogenes or salmonella enterica serovar poona, using strains implicated in outbreaks, were treated with one of 17 antagonists originally selected for their ability to inhibit fungal postharvest decay on fruit. while most of the antagonists increased the growth of the food-borne pathogens, four of them, including gluconobacter asaii (t1-d1), a candida sp. (t4-e4), discosphaerina fagi (st1-c9), and metschnikowia pulcherrima (t1-e2), proved ef ... | 2006 | 16461659 |
| determination of essential and variable residues in pediocin pa-1 by nnk scanning. | pediocin pa-1 is an antimicrobial peptide (called bacteriocin) that shows inhibitory activity against the food-borne pathogen listeria monocytogenes. to elucidate which residue(s) is responsible for this function, the antimicrobial activities of pediocin pa-1 mutants were evaluated and compared. each of the 44 native codons was replaced with the nnk triplet oligonucleotide in a technique termed nnk scanning, and 35 mutations at each position were examined for antimicrobial activities using a mod ... | 2006 | 16461660 |
| two subpopulations of listeria monocytogenes occur at subinhibitory concentrations of leucocin 4010 and nisin. | in situ analyses of single listeria monocytogenes cells at subinhibitory concentrations of leucocin 4010 and nisin revealed two subpopulations when measured by fluorescence ratio imaging microscopy (frim) after staining with 5(6)-carboxyfluorescein diacetate succinimidyl ester. one subpopulation consisted of cells with a dissipated ph gradient (deltaph), and the other consisted of cells that maintained deltaph. the proportion of cells belonging to each subpopulation was estimated, and the concen ... | 2006 | 16461719 |
| caenorhabditis elegans is a model host for listeria monocytogenes. | here we report that caenorhabditis elegans nematodes fed listeria monocytogenes die over the course of several days, as a consequence of an accumulation of bacteria in the worm intestine. mutant strains previously shown to be important for virulence in mammalian models were also found to be attenuated in their virulence in c. elegans. however, acta, which is required for actin-based intracellular motility, appears to be dispensable during infection of c. elegans, indicating that l. monocytogenes ... | 2006 | 16461732 |
| 13c isotopologue perturbation studies of listeria monocytogenes carbon metabolism and its modulation by the virulence regulator prfa. | the carbon metabolism of listeria monocytogenes (lm) egd and the two isogenic mutant strains lmdeltaprfa and lmdeltaprfapprfa* (showing no or enhanced expression, respectively, of the virulence factor prfa) was determined by 13c isotopologue perturbation. after growth of the bacteria in a defined medium containing a mixture of [u-13c6]glucose and glucose with natural 13c abundance (1:25, wt/wt), 14 amino acids were isolated and analyzed by nmr spectroscopy. multiply 13c-labeled isotopologues wer ... | 2006 | 16461909 |
| sensor molecules in intestinal innate immunity against bacterial infections. | toll-like receptors (tlrs) and nucleotide-binding oligomerization domain (nod)-containing proteins are innate immune sensors for microbial signature molecules. this review highlights new insights into the functions of these sensors in intestinal physiology. | 2006 | 16462163 |
| population-based incidence of infection with selected bacterial enteric pathogens in children younger than five years of age, 1996-1998. | previous studies of bacterial enteric infections have suggested a disproportionate disease burden for children younger than 5 years of age. | 2006 | 16462289 |
| monocyte emigration from bone marrow during bacterial infection requires signals mediated by chemokine receptor ccr2. | monocytes recruited to tissues mediate defense against microbes or contribute to inflammatory diseases. regulation of the number of circulating monocytes thus has implications for disease pathogenesis. however, the mechanisms controlling monocyte emigration from the bone marrow niche where they are generated remain undefined. we demonstrate here that the chemokine receptor ccr2 was required for emigration of ly6c(hi) monocytes from bone marrow. ccr2(-/-) mice had fewer circulating ly6c(hi) monoc ... | 2006 | 16462739 |
| species specificity of the listeria monocytogenes inlb protein. | inla and inlb mediate l. monocytogenes entry into eukaryotic cells. inla is required for the crossing of the intestinal and placental barriers. inla uses e-cadherin as receptor in a species-specific manner. the human e-cadherin but not the mouse e-cadherin is a receptor for inla. in human cells, inlb uses met and gc1qr as receptors. by studying the role of inlb in vivo, we found that activation of met by inlb is species-specific. in mice, inlb is important for liver and spleen colonization, but ... | 2006 | 16469057 |
| genomic dissection of microbial pathogenesis in cultured drosophila cells. | recent rna interference screens that were performed at a genome-wide level have identified host factors that are important for the growth of listeria monocytogenes in cultured cells from the fruit fly drosophila melanogaster. the screens identified genes that are involved in phagocytosis but did not detect genes known to be involved in immune signaling pathways. these studies provide a foundation for the identification of host factors and virulence mechanisms. | 2006 | 16473012 |