Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| targeting of antigen to dendritic cells with poly(gamma-glutamic acid) nanoparticles induces antigen-specific humoral and cellular immunity. | nanoparticles are considered to be efficient tools for inducing potent immune responses by an ag carrier. in this study, we examined the effect of ag-carrying biodegradable poly(gamma-glutamic acid) (gamma-pga) nanoparticles (nps) on the induction of immune responses in mice. the nps were efficiently taken up by dendritic cells (dcs) and subsequently localized in the lysosomal compartments. gamma-pga nps strongly induced cytokine production, up-regulation of costimulatory molecules, and the enha ... | 2007 | 17312143 |
| interleukin-1 receptor type 1 is essential for control of cerebral but not systemic listeriosis. | listeria monocytogenes may infect the central nervous system and several peripheral organs. to explore the function of il-1 receptor type 1 (il-1r1) in cerebral versus systemic listeriosis, il-1r1(-/-) and wild-type mice were infected either intracerebrally or intraperitoneally with l. monocytogenes. after intracerebral infection with various numbers of attenuated listeria, il-1r1(-/-) mice succumbed due to an insufficient control of intracerebral listeria, whereas all wild-type mice survived, e ... | 2007 | 17322383 |
| immunoediting sculpts tumor epitopes during immunotherapy. | immunoediting of tumor-associated antigens occurs in response to immune pressure. we show that the mutation of residues within epitopes of her-2/neu leads to the outgrowth of autochthonous tumors after immunizing her-2/neu transgenic mice with listeria monocytogenes therapeutic vaccines expressing fragments of her-2/neu. three of these vaccines target the extracellular domain (lmllo-ec1, lmllo-ec2, and lmllo-ec3), and two of these vaccines target the intracellular domain (lm-llo-ic1 and lm-llo-i ... | 2007 | 17332314 |
| asymmetric t lymphocyte division in the initiation of adaptive immune responses. | a hallmark of mammalian immunity is the heterogeneity of cell fate that exists among pathogen-experienced lymphocytes. we show that a dividing t lymphocyte initially responding to a microbe exhibits unequal partitioning of proteins that mediate signaling, cell fate specification, and asymmetric cell division. asymmetric segregation of determinants appears to be coordinated by prolonged interaction between the t cell and its antigen-presenting cell before division. additionally, the first two dau ... | 2007 | 17332376 |
| listeria--review of epidemiology and pathogenesis. | listeria monocytogenes (commonly called listeria) is a gram-positive facultatively intracellular foodborne pathogen often found in food and elsewhere in nature. it can cause a rare but serious disease called listeriosis, especially among pregnant women, the elderly or individuals with a weakened immune system. in serious cases, it can lead to brain infection and even death. listeria is more likely to cause death than other bacteria that cause food poisoning. in fact, 20 to 30% of food borne list ... | 2007 | 17332901 |
| a p60 mutant of listeria monocytogenes is impaired in its ability to cause infection in intragastrically inoculated mice. | a spontaneous p60 mutant of listeria monocytogenes was less able to cause systemic infection in a/j mice, following intragastric inoculation, than the parental wild type strain (slcc 5764, serotype 1/2a). significantly fewer cfu were recovered from internal organs (spleen, liver, gall bladder) and from the cecum of mice inoculated intragastrically with the p60 mutant than mice inoculated with wild type l. monocytogenes. the p60 mutant also exhibited a diminished ability to invade and multiply wi ... | 2007 | 17336491 |
| quantification of gene expression of listeria monocytogenes by real-time reverse transcription pcr: optimization, evaluation and pitfalls. | in the current study, various steps in the real-time reverse transcription pcr (real-time rt-pcr) method for determination of rna expression levels starting from different numbers of listeria monocytogenes cells were evaluated and optimized. our results showed that the rna isolation method as well as the cdna synthesis may influence the sensitivity of the procedure. for high bacterial cell numbers (10(9) bacterial cells), the rnaqueous kit and the rneasy mini kit were equally useful, whereas for ... | 2007 | 17337308 |
| occurrence and persistence of listeria spp. in the environment of ewe and cow's milk cheese dairies in portugal unveiled by an integrated analysis of identification, typing and spatial-temporal mapping along production cycle. | eight dairies, located in two distant geographic regions of portugal, were screened along the production cycle in order to evaluate the presence and distribution of listeria spp. in their environment. three dairies in each region were positive for the presence of listeriae and 213 isolates were obtained. based on an integrated analysis of rapd fingerprints with three primers, molecular identification and genomic typing of isolates was performed followed by spatial and temporal mapping on dairy p ... | 2007 | 17337311 |
| the alternative sigma factor sigma b and the virulence gene regulator prfa both regulate transcription of listeria monocytogenes internalins. | some listeria monocytogenes internalins are recognized as contributing to invasion of mammalian tissue culture cells. while prfa is well established as a positive regulator of l. monocytogenes virulence gene expression, the stress-responsive sigma(b) has been recognized only recently as contributing to expression of virulence genes, including some that encode internalins. to measure the relative contributions of prfa and sigma(b) to internalin gene transcription, we used reverse transcription-pc ... | 2007 | 17337550 |
| temperature-dependent expression of listeria monocytogenes internalin and internalin-like genes suggests functional diversity of these proteins among the listeriae. | the listeria monocytogenes genome contains genes encoding several internalins and internalin-like proteins. as l. monocytogenes is present in many environments and can infect numerous, diverse host species, the environmental temperature was hypothesized to be a signal that might affect internalin gene transcription. a subgenomic microarray was used to investigate temperature-dependent transcription of 24 members of the internalin gene family in l. monocytogenes 10403s. the levels of internalin g ... | 2007 | 17337561 |
| outbreak of listeriosis in the czech republic, late 2006--preliminary report. | 2007 | 17370949 | |
| functional plasticity in memory t helper cell responses. | following activation, naive cd4+ th cells can differentiate to selectively produce either the th1 lineage-specific cytokine ifn-gamma or the th2 cytokine il-4 and, in so doing, lose the capacity to produce cytokines of the alternative lineage. lineage commitment of murine cd4+ t cells has largely been considered to be absolute with little flexibility to produce cytokines of the opposing lineage. in this study, we demonstrate that cells within th2 memory populations can produce ifn-gamma if react ... | 2007 | 17371962 |
| nk dendritic cells are innate immune responders to listeria monocytogenes infection. | nk dendritic cells (nkdc) are recently described immunologic cells that possess both lytic and ag-presenting function and produce prolific quantities of ifn-gamma. the role of nkdc in innate immunity to bacterial infection is unknown. because ifn-gamma is important in the immune response to listeria monocytogenes (lm), we hypothesized that nkdc play a critical role during lm infection in mice. we found that lm increased the frequency and activation state of nkdc in vivo. using in vivo intracellu ... | 2007 | 17371998 |
| tyk2 signaling in host environment plays an important role in contraction of antigen-specific cd8+ t cells following a microbial infection. | tyrosine kinase 2 (tyk2), a member of jak signal transducer family contributes to the signals triggered by il-12 for ifn-gamma production. to elucidate potential roles of tyk2 in generation and maintenance of ag-specific cd8+ t cells, we followed the fate of ova-specific cd8+ t cells in tyk2-deficient (-/-) mice after infection with recombinant listeria monocytogenes expressing ova (rlm-ova). results showed that the numbers of ova(257-264)/k(b) tetramer-positive cd8+ t cells in tyk2(-/-) mice we ... | 2007 | 17372006 |
| il-12 and type-i ifn synergize for ifn-gamma production by cd4 t cells, whereas neither are required for ifn-gamma production by cd8 t cells after listeria monocytogenes infection. | differentiation of ag-specific t cells into ifn-gamma producers is essential for protective immunity to intracellular pathogens. in addition to stimulation through the tcr and costimulatory molecules, ifn-gamma production is thought to require other inflammatory cytokines. two such inflammatory cytokines are il-12 and type i ifn (ifn-i); both can play a role in priming naive t cells to produce ifn-gamma in vitro. however, their role in priming ag-specific t cells for ifn-gamma production during ... | 2007 | 17372008 |
| quantitative recovery of listeria monocytogenes and select salmonella serotypes from environmental sample media. | environmental sampling has become increasingly important in the food industry for monitoring the presence of specific pathogens such as listeria monocytogenes and salmonella enterica. several microbiological media are available for storage and transport of environmental samples from the processing plant to the test laboratory. in this study, we quantified the survival of l. monocytogenes, s. typhimurium, s. enteritidis, and s. typhi in environmental sampling media over several time and temperatu ... | 2007 | 17373457 |
| inactivation of foodborne pathogens using a one atmosphere uniform glow discharge plasma. | this study was conducted to determine the efficacy of a one atmosphere uniform glow discharge plasma (oaugdp) for inactivation of foodborne pathogens and to evaluate the influence of growth temperature, ph, and culture age on their inactivation. escherichia coli o157:h7, listeria monocytogenes, staphylococcus aureus, bacillus cereus, salmonella enteritidis, vibrio parahaemolyticus, yersinia enterocolitica, and shigella flexneri were evaluated. three-strain mixtures of each bacterium were inocula ... | 2007 | 17378708 |
| evaluation of the pathogenicity of listeria spp. in caenorhabditis elegans. | caenorhabditis has proven to be a useful model for studying host-pathogen interactions as well as the ability of nematodes to serve as vectors for the dispersal of foodborne pathogens. in this study, we evaluated whether c. elegans can serve as a host for listeria spp. while there was an effect of growth media on c. elegans killing, c. elegans exposed to l. monocytogenes and l. innocua pregrown in luria-bertani medium showed reduced survival when compared to nonpathogenic e. coli op50, while l. ... | 2007 | 17378710 |
| development of listeria monocytogenes-specific immunomagnetic beads using a single-chain antibody fragment. | a method for coupling single-chain antibody fragments (scfvs) to immunomagnetic beads (imbs) was developed and evaluated using scfvs specific for listeria monocytogenes. a plasmid vector, pbad380, was constructed that allowed the expression of histidine-tagged biotinylated scfvs in escherichia coli. the gene encoding a scfv specific for l. monocytogenes was cloned into pbad380 and the 6-histidine-tagged biotinylated anti-l. monocytogenes scfvs were coupled to streptavidin-coated imbs. the abilit ... | 2007 | 17378711 |
| influence of immunomodulation on the development of listeria monocytogenes infection in aged guinea pigs. | we investigated the impact of immunomodulation on the development of listeriosis within an aged population of guinea pigs after an intragastric challenge with listeria monocytogenes. supplementation with vitamin e for 35 days significantly increased the level of cytotoxic t cells (cd8(+)), while treatment with cyclosporin a resulted in a 25% decrease of cd8(+) t cells. in the animals receiving the low dose (10(2) cfu) of l. monocytogenes, 50% of the control-group animals became infected. only 22 ... | 2007 | 17378902 |
| a naturally occurring mutation k220t in the pleiotropic activator prfa of listeria monocytogenes results in a loss of virulence due to decreasing dna-binding affinity. | the sequencing of prfa, encoding the transcriptional regulator of virulence genes, in 26 low-virulence field listeria monocytogenes strains showed that eight strains exhibited the same single amino-acid substitution: prfak220t. these strains exhibited no expression of prfa-regulated proteins and thus no virulence. this substitution inactivated prfa, since expression of the prfak220t mutant gene in an egddeltaprfa strain did not restore the haemolytic and phosphatidylcholine phospholipase c activ ... | 2007 | 17379709 |
| molecular characterization of the fur protein of listeria monocytogenes. | iron is essential for the survival of almost all organisms, although excess iron can result in the generation of free radicals which are toxic to cells. to avoid the toxic effects of free radicals, the concentration of intracellular iron is generally regulated by the ferric uptake regulator fur in bacteria. the 150 aa fur orf from listeria monocytogenes was cloned into prseta, and the his-tagged fusion protein was purified by nickel affinity column chromatography. dna binding activity of this pr ... | 2007 | 17379719 |
| immunology. asymmetry and immune memory. | 2007 | 17379796 | |
| antimicrobial activity of bacillus subtilis and bacillus pumilus during the fermentation of african locust bean (parkia biglobosa) for soumbala production. | to examine predominant isolates of bacillus subtilis and b. pumilus isolated from soumbala for their antimicrobial activity against indicator microorganisms as micrococcus luteus, staphyloccocus aureus, bacillus cereus, enterococus facium, listeria monocytogenes, escherichia coli, salmonella typhimurium, shigella dysenteriae, yersinia enterocolitica, aspergillus ochraceus and penicillium roqueforti. | 2007 | 17381739 |
| role of caspase-8 in hepatocyte response to infection and injury in mice. | caspase-8 has been implicated in signaling for apoptotic cell death and for certain nonapoptotic functions. however, knowledge of actual physiological or pathophysiological processes to which this enzyme contributes is lacking. using a mouse model and employing the conditional knockout approach to delete the caspase-8 gene specifically in the liver, we found that caspase-8 deficiency in hepatocytes facilitates infection of the liver by listeria monocytogenes, attenuates the hepatocyte proliferat ... | 2007 | 17385212 |
| rapid detection of escherichia coli o157:h7 spiked into food matrices. | food poisoning causes untold discomfort to many people each year. one of the primary culprits in food poisoning is escherichia coli o157:h7. while most cases cause intestinal discomfort, up to 7% of the incidences lead to a severe complication called hemolytic uremic syndrome which may be fatal. the traditional method for detection of e. coli o157:h7 in cases of food poisoning is to culture the food matrices and/or human stool. additional performance-based antibody methods are also being used. t ... | 2007 | 17386586 |
| axonal transport of listeria monocytogenes and nerve-cell-induced bacterial killing. | listeria monocytogenes (l. monocytogenes) can cause fatal brainstem encephalitis in both sheep and humans. here we review evidence that the bacteria can be incorporated into axons following a primary cycle of replication in macrophages/dendritic cells after subcutaneous injection in projection areas of peripheral neurons. the molecular mechanisms for the rocketing of l. monocytogenes in the cytosol by asymmetric cometic tails and the utility of this phenomenon for bacterial migration intraaxonal ... | 2007 | 17387705 |
| isolation and molecular characterization of antibiotic-resistant lactic acid bacteria from poultry and swine meat products. | the transfer via the food chain from animals to humans of microbes that are resistant to antimicrobial agents is of increasing concern. to determine the contributions of nonpathogenic microflora to the occurrence and spread of antibiotic resistance (ar) genes in the food chain, 123 lactic acid bacteria were isolated from 29 samples of raw and processed pork and chicken meat products that had previously tested positive for one or more ar genes that encode clinically relevant ars: tet(m), tet(o), ... | 2007 | 17388042 |
| distribution of epidemic clonal genetic markers among listeria monocytogenes 4b isolates. | recent genome sequencing of isolates of listeria monocytogenes serotype 4b implicated in some major outbreaks of foodborne listeriosis has revealed unique genetic markers in these isolates. the isolates were grouped into two distinct epidemic clones, eci and ecii. in the present study, selected eci- and ecii-specific genetic markers were detected in 16 and 15 of 89 l. monocytogenes 4b isolates, respectively. the eci markers were found in 6 of 34 clinical isolates, 9 of 50 food isolates, and 1 of ... | 2007 | 17388044 |
| sodium chloride enhances adherence and aggregation and strain variation influences invasiveness of listeria monocytogenes strains. | some subtypes of listeria monocytogenes can persist in the food-processing industry, but the reasons for such persistence are not known. in the present study, 10 strains of l. monocytogenes representing known persistent randomly amplified polymorphic dna (rapd) types from fish processing plants were compared to eight strains of different rapd type and origin (clinical, food, and animal). all 18 strains of l. monocytogenes had similar growth patterns at different temperatures (5 or 37 degrees c) ... | 2007 | 17388046 |
| evaluation of the transfer of listeria monocytogenes from stainless steel and high-density polyethylene to bologna and american cheese. | the objective of this study was to determine the factors involved in the transfer of listeria monocytogenes from surfaces to foods. we evaluated the influence of surface type (stainless steel and high-density polyethylene), inoculation method (biofilm growth and attached cells), hydration level (visibly dry and wet), and food type (bologna and american cheese). each experiment included all 16 combinations and was repeated 11 times. a four-strain cocktail of l. monocytogenes was used to inoculate ... | 2007 | 17388047 |
| quantitative effect of refrigerated storage time on the enumeration of campylobacter, listeria, and salmonella on artificially inoculated raw chicken meat. | active monitoring of pathogens on retail foods has been recommended and implemented in a number of developed countries. because only a portion of retail food is contaminated with pathogens, a cost-effective and informative surveillance program at the retail level often involves a two-stage approach of initial presence-absence analysis and subsequent pathogen enumeration in any positive samples. most-probable-number (mpn) methods are more resource intensive and therefore used only for samples con ... | 2007 | 17388068 |
| modeling the growth of listeria monocytogenes in pasteurized white asparagus. | growth of listeria monocytogenes in pasteurized white asparagus was monitored at different storage temperatures (4, 10, 20, and 30 degrees c). among the main microbial kinetic parameters, growth rate (mu) per hour was calculated at each temperature using the baranyi-roberts model. l. monocytogenes was able to grow at all temperatures, although at 4 degrees c only a slight increment of the microbial population was observed (approximately 1 log cfu/g) after 300 h of storage. subsequently, two diff ... | 2007 | 17388071 |
| ultrasonic cleaning of conveyor belt materials using listeria monocytogenes as a model organism. | persistent listeria monocytogenes contamination of food industry equipment is a difficult problem to solve. ultrasonic cleaning offers new possibilities for cleaning conveyors and other equipment that are not easy to clean. ultrasonic cleaning was tested on three conveyor belt materials: polypropylene, acetal, and stainless steel (cold-rolled, aisi 304). cleaning efficiency was tested at two temperatures (30 and 45 degrees c) and two cleaning times (30 and 60 s) with two cleaning detergents (koh ... | 2007 | 17388072 |
| functional genomic studies of the intestinal response to a foodborne enteropathogen in a humanized gnotobiotic mouse model. | members of the genus listeria provide a model for defining host responses to invasive foodborne enteropathogens. active translocation of listeria monocytogenes across the gut epithelial barrier is mediated by interaction of bacterial internalin (inla) and its species-specific host receptor, e-cadherin, whereas translocation across peyer's patches through m-cells is inla-independent. to define microbial determinants and molecular correlates of the host response to translocation via these two rout ... | 2007 | 17389602 |
| bacterial ligands generated in a phagosome are targets of the cytosolic innate immune system. | macrophages are permissive hosts to intracellular pathogens, but upon activation become microbiocidal effectors of innate and cell-mediated immunity. how the fate of internalized microorganisms is monitored by macrophages, and how that information is integrated to stimulate specific immune responses is not understood. activation of macrophages with interferon (ifn)-gamma leads to rapid killing and degradation of listeria monocytogenes in a phagosome, thus preventing escape of bacteria to the cyt ... | 2007 | 17397264 |
| prevalence and growth of listeria monocytogenes in naturally contaminated cold-smoked salmon. | to investigate listeria monocytogenes contamination and behaviour in naturally contaminated french cold-smoked salmon (css). | 2007 | 17397479 |
| cutting edge: recombinant listeria monocytogenes expressing a single immune-dominant peptide confers protective immunity to herpes simplex virus-1 infection. | the vast majority of the world's population is infected with hsv. although antiviral therapy can reduce the incidence of reactivation and asymptomatic viral shedding, and limit morbidity and mortality from active disease, it cannot cure infection. therefore, the development of an effective vaccine is an important global health priority. in this study, we demonstrate that recombinant listeria monocytogenes (lm) expressing the h-2k(b) glycoprotein b (gb)(498-505) peptide from hsv-1 triggers a robu ... | 2007 | 17404252 |
| beta1-adrenergic receptors on immune cells impair innate defenses against listeria. | cold restraint (cr) for 1 h elicits a psychological and physiological stress that inhibits host defenses against listeria monocytogenes (lm). previous analyses indicated that this inhibition is not due to depletion of b or t cells but is instead dependent on signaling through beta-adrenoceptors (betaars). we now show that impaired host resistance by cr cannot be accounted for by a decrease in lm-specific (listeriolysin o(91-99) tetramer(+)) effector cd8(+) t cells; this result is consistent with ... | 2007 | 17404268 |
| myd88-dependent activation of b220-cd11b+ly-6c+ dendritic cells during brucella melitensis infection. | ifn-gamma is a key cytokine controlling brucella infection. one of its major function is the stimulation of brucella-killing effector mechanisms, such as inducible no synthase (inos)/nos2 activity, in phagocytic cells. in this study, an attempt to identify the main cellular components of the immune response induced by brucella melitensis in vivo is made. ifn-gamma and inos protein were analyzed intracellularly using flow cytometry in chronically infected mice. although tcrbeta(+)cd4(+) cells wer ... | 2007 | 17404301 |
| [one episode of meningoencephalitis, three diagnoses]. | meningo-encephalitis is a set of threatening diseases. the treatment needs to be started quickly for pathogens such as herpes simplex virus type 1 or listeria monocytogenes. apart from these classical etiologies, many other diseases may induce meningo-encephalitis. we report the case of a patient, infected with hiv, who presented a history of meningo-encephalitis due to herpes simplex type 1. three weeks later, he presented an encephalopathy due to aciclovir and then we discovered a chronic meni ... | 2007 | 17404526 |
| [survey of the presence of listeria monocytogenes in meat products sold in retail]. | the present study evaluates the presence of listeria spp and particularly of l. monocytogenes in bovine, pork and poultry meats sold by retail in supermarkets and butchers in the city of cassino. the sensibility to the antibiotics mostly used in the veterinary practice has been tested on the isolated strains. the different species of listeria have shown a considerable variation of isolation based on the meat's typology and on the different store's provenance. moreover our results show greater de ... | 2007 | 17405508 |
| a rare case of brainstem encephalitis by listeria monocytogenes with isolated mesencephalic localization. case report and review. | we describe a case of brainstem infection by listeria monocytogenes with right oculomotor palsy and lip drop, facial hypoesthesia, left arm paresthesia, positive blood culture, and sterile liquor in a 63-year-old man. magnetic resonance imaging revealed an isolated mesencephalic lesion. localization of this kind accounted for 3% of 111 cases reviewed. | 2007 | 17408902 |
| multiplexed identification of blood-borne bacterial pathogens by use of a novel 16s rrna gene pcr-ligase detection reaction-capillary electrophoresis assay. | we have developed a novel high-throughput pcr-ligase detection reaction-capillary electrophoresis (pcr-ldr-ce) assay for the multiplexed identification of 20 blood-borne pathogens (staphylococcus epidermidis, staphylococcus aureus, bacillus cereus, enterococcus faecalis, enterococcus faecium, listeria monocytogenes, streptococcus pneumoniae, streptococcus pyogenes, streptococcus agalactiae, escherichia coli, klebsiella pneumoniae, haemophilus influenzae, pseudomonas aeruginosa, acinetobacter bau ... | 2007 | 17428930 |
| longitudinal monitoring of listeria monocytogenes contamination patterns in a farmstead dairy processing facility. | contamination of dairy products with listeria monocytogenes is a concern because multiple human listeriosis outbreaks have been linked to contaminated cheese and dairy products. dairy production on farmstead operations may be a particular concern because l. monocytogenes is also an animal pathogen that can be shed by ruminants with and without clinical symptoms; physical proximity between production animal and dairy processing facilities may thus provide a higher risk for introduction of l. mono ... | 2007 | 17430956 |
| the resistance to detachment of dairy strains of listeria monocytogenes from stainless steel by shear stress is related to the fluid dynamic characteristics of the location of isolation. | strains of listeria monocytogenes isolated from artisanal portuguese cheese-making dairies were divided into two categories on the basis of the locations from which they were isolated: strains from dynamic locations were those that were habitually exposed to flowing liquids during the process of cheese-making, whereas those from static locations were rarely, if ever, exposed to the shear stresses generated by liquid flows. the strength of attachment to stainless steel discs of all of these strai ... | 2007 | 17433481 |
| gut osmolarity: a key environmental cue initiating the gastrointestinal phase of listeria monocytogenes infection? | in addition to the severe invasive systemic disease of listeriosis, recent evidence suggests that the gram-positive intracellular bacterial pathogen listeria monocytogenes is also a causative agent of febrile gastroenteritis. we examined the listerial response to stresses normally encountered in the upper small intestine and demonstrate that osmotic stress appears to be at the top of the hierarchy of stress responses during gastrointestinal residence. furthermore, we suggest that the increased o ... | 2007 | 17433559 |
| a subacute bacterial endocarditis in a patient with aortic prosthetic valve due to listeria monocytogenes presenting with perivalvular leak. | 2007 | 17434622 | |
| germicidal ultraviolet light to lower numbers of listeria monocytogenes on broiler breast fillets. | raw broiler breast fillets were subjected to germicidal ultraviolet (uv) light (dose of 1,000 microw/cm(2) for 5 min at a wavelength of 254 nm) to evaluate its potential to reduce listeria monocytogenes numbers on raw product before shipment to a poultry further-processing plant. boneless, skinless breast fillets were inoculated with 4 different strains of l. monocytogenes 5 min before treatment. after the uv treatment, breast fillets were stored at 4 degrees c for 24 h. enumeration of remaining ... | 2007 | 17435033 |
| some essential elements on the inlc promoter for prfa-dependent regulation in listeria monocytogenes. | to study some essential elements of a prfa-dependent promoter of listeria monocytogenes, a series of promoter mutants incorporated into upstream of a promoterless lacz gene were constructed from a known listerial prfa-dependent promoter, inlc promoter, by pcr-mediated site-directed mutagenesis and recombinant pcr technique and then electroporated into l. monocytogenes wild-type strain p14, prfa * mutant pl4a and prfa deletion mutant a42. the corresponding transcription activities of altered prom ... | 2007 | 17436618 |
| characteristics of cell-mediated, anti-listerial immunity induced by a naturally avirulent listeria monocytogenes serotype 4a strain hcc23. | the characteristics of cell-mediated, anti-listerial immune response initiated by an avirulent listeria monocytogenes serotype 4a strain hcc23 was assessed. similar to virulent strain egd, avirulent strain hcc23 grew readily within macrophage-like j774 cells, but nonhemolytic strain atcc 15313 did not. compared with egd, hcc23 induced a relatively low level of gamma interferon (ifn-gamma) in mice, and atcc 15313 stimulated no detectable ifn-gamma. the percentages of gated cd4 t cells from mice i ... | 2007 | 17437086 |
| memory cd4 t cells enhance primary cd8 t-cell responses. | cd4 t-cell help is required for optimal memory cd8 t-cell responses. we have found that engaging preexisting cd4 th1, but not th2, memory cells at the time of cd8 t-cell priming results in increased cd8 effector responses to both bacterial and viral pathogens. the enhanced responses are characterized by increased numbers of cytokine-producing, antigen-specific cells. these findings suggest that engaging endogenous memory th1 cells may increase cellular responses in an immunotherapy or vaccinatio ... | 2007 | 17438031 |
| antigen presentation by nonhemopoietic cells amplifies clonal expansion of effector cd8 t cells in a pathogen-specific manner. | professional apcs of hemopoietic-origin prime pathogen-specific naive cd8 t cells. the primed cd8 t cells can encounter ag on infected nonhemopoietic cell types. whether these nonhemopoietic interactions perpetuate effector t cell expansion remains unknown. we addressed this question in vivo, using four viral and bacterial pathogens, by comparing expansion of effector cd8 t cells in bone marrow chimeric mice expressing restricting mhc on all cell types vs mice that specifically lack restricting ... | 2007 | 17442964 |
| anthrax lethal toxin paralyzes actin-based motility by blocking hsp27 phosphorylation. | inhalation of anthrax causes fatal bacteremia, indicating a meager host immune response. we previously showed that anthrax lethal toxin (lt) paralyzes neutrophils, a major component of innate immunity. here, we have found that lt also inhibits actin-based motility of the intracellular pathogen listeria monocytogenes. lt inhibition of actin assembly is mediated by blockade of hsp27 phosphorylation, and can be reproduced by treating cells with the p38 mitogen-activated protein (map) kinase inhibit ... | 2007 | 17446863 |
| the in vitro antibacterial activity of dietary spice and medicinal herb extracts. | the in vitro antibacterial activities of a total of 46 extracts from dietary spices and medicinal herbs were investigated by agar-well diffusion method against five foodborne bacteria (bacillus cereus, listeria monocytogenes, staphylococcus aureus, escherichia coli, and salmonella anatum). their total phenolic contents were also evaluated. many herb and spice extracts contained high levels of phenolics and exhibited antibacterial activity against foodborne pathogens. gram-positive bacteria were ... | 2007 | 17449125 |
| insufficient differentiation of live and dead campylobacter jejuni and listeria monocytogenes cells by ethidium monoazide (ema) compromises ema/real-time pcr. | recently, ethidium monoazide (ema) has been proposed as a means of reducing the real-time pcr signal originating from free dna and dead bacterial cells by selectively entering damaged cells and blocking the dna for pcr amplification via photoactivation. the present study investigated the effect of ema on viable and dead bacterial cells using real-time pcr, plate count method and microscopy. the foodborne pathogens campylobacter jejuni and listeria monocytogenes were used as a gram-negative and a ... | 2007 | 17449228 |
| recurrent and sporadic listeria monocytogenes contamination in alheiras represents considerable diversity, including virulence-attenuated isolates. | microbiological characterization of alheiras, traditional smoked meat sausages produced in northern portugal, had previously shown that more than 60% of the lots analyzed were contaminated with listeria monocytogenes at levels higher than 100 cfu/g. in order to better understand l. monocytogenes contamination patterns in alheiras, we characterized 128 l. monocytogenes isolates from alheiras using a variety of subtyping techniques (i.e., molecular serotyping; arsenic, cadmium, and tetracycline re ... | 2007 | 17449681 |
| short peptides derived from the nh2-terminus of subclass iia bacteriocin enterocin crl35 show antimicrobial activity. | subclass iia bacteriocins are characterized by a hydrophilic n-terminal domain that shares a ygngvxcxxxxc consensus and a variable hydrophobic c-terminus. enterocin crl35 is a 43-amino-acid heat stable peptide with antilisterial activity. short synthetic peptides derived from the n-terminal half of enterocin crl35 and other subclass iia bacteriocins were evaluated for antimicrobial properties. | 2007 | 17449885 |
| an oral salmonella vaccine promotes the down-regulation of cell surface toll-like receptor 4 (tlr4) and tlr2 expression in mice. | a single oral immunization with the lon-protease-deficient salmonella enterica serovar typhimurium (strain cs2022) induced protective immunity in mice against a subcutaneous challenge with virulent listeria monocytogenes as well as virulent salmonella serovar typhimurium. the populations of cell surface toll-like receptor 4 (tlr4) and tlr2 on peritoneal macrophages decreased at week 6 after immunization. this population decrease was not reversed after a challenge with either salmonella or lister ... | 2007 | 17451442 |
| adapter protein sh2-bbeta stimulates actin-based motility of listeria monocytogenes in a vasodilator-stimulated phosphoprotein (vasp)-dependent fashion. | sh2-bbeta (src homology 2 bbeta) is an adapter protein that is required for maximal growth hormone-dependent actin reorganization in membrane ruffling and cell motility. here we show that sh2-bbeta is also required for maximal actin-based motility of listeria monocytogenes. sh2-bbeta localizes to listeria-induced actin tails and increases the rate of bacterial propulsion in infected cells and in cell extracts. furthermore, listeria motility is decreased in mouse embryo fibroblasts from sh2-b(-/- ... | 2007 | 17452473 |
| type i interferon signaling is required for activation of the inflammasome during francisella infection. | francisella tularensis is a pathogenic bacterium whose virulence is linked to its ability to replicate within the host cell cytosol. entry into the macrophage cytosol activates a host-protective multimolecular complex called the inflammasome to release the proinflammatory cytokines interleukin (il)-1beta and -18 and trigger caspase-1-dependent cell death. in this study, we show that cytosolic f. tularensis subspecies novicida (f. novicida) induces a type i interferon (ifn) response that is essen ... | 2007 | 17452523 |
| diffusion-weighted magnetic resonance imaging in rhombencephalitis due to listeria monocytogenes. | we present diffusion-weighted imaging findings of a case of rhombencephalitis due to listeria monocytogenes. it is a rare, life-threatening disorder. the diagnosis is difficult by clinical findings only. in this report, we aim to draw attention to the role of conventional and diffusion-weighted magnetic resonance imaging findings. to our knowledge, this is the first case report in the literature with apparent diffusion coefficient values of diseased brain parenchyma. | 2007 | 17453530 |
| suppression of phagocytic and bactericidal functions of rat alveolar macrophages by the organic component of diesel exhaust particles. | exposure to diesel exhaust particles (dep) was shown to increase the susceptibility of the lung to bacterial infection in rats. in this study, the effects of dep on alveolar macrophage (am) phagocytic and bactericidal functions and cytokine secretion by am and lymphocytes in response to listeria monocytogenes infection were investigated in vitro and the roles of different dep components in these processes were compared. exposure to dep or the organic extracts of dep (edep) significantly decrease ... | 2007 | 17454558 |
| bacteriocin production as a mechanism for the antiinfective activity of lactobacillus salivarius ucc118. | the mechanisms by which probiotic strains enhance the health of the host remain largely uncharacterized. here we demonstrate that lactobacillus salivarius ucc118, a recently sequenced and genetically tractable probiotic strain of human origin, produces a bacteriocin in vivo that can significantly protect mice against infection with the invasive foodborne pathogen listeria monocytogenes. a stable mutant of lb. salivarius ucc118 that is unable to produce the abp118 bacteriocin also failed to prote ... | 2007 | 17456596 |
| necrotizing encephalitis of unknown cause in fennoscandian arctic foxes (alopex lagopus). | a neurologic disease affected a colony of endangered fennoscandian arctic foxes (alopex lagopus) kept in captivity for breeding purposes. several outbreaks of disease occurred between 1994 and 2004. the clinical signs included ataxia, indications of anosmia, blindness, and abnormal behavior. the disease was characterized by severe necrotizing encephalitis affecting mostly the cranial cerebrum, basal ganglia, and olfactory bulbs. investigations to identify the etiology of the disease included tes ... | 2007 | 17459845 |
| the onset of rapidly progressive neurologic deterioration after a brief gastrointestinal illness in a renal allograft recipient. | renal transplant recipients are at increased risk for life-threatening complications, most commonly infections. because of their impaired cell-mediated immunity, these patients are particularly susceptible to organisms that rely on intracellular survival and spread, such as listeria monocytogenes. despite being a food-borne pathogen, l. monocytogenes is associated with significant morbidity and mortality. here we report the case of a renal transplant recipient who developed rapidly progressive n ... | 2007 | 17462001 |
| application of real-time quantitative pcr for the detection of selected bacterial pathogens during municipal wastewater treatment. | bacteria were detected at five stages of municipal wastewater treatment using taqman(r) real-time quantitative pcr (qpcr). thirteen probe and primer sets were tested for diverse pathogens that may be present in wastewater, including aeromonas hydrophila, bacillus cereus, clostridium perfringens, enterococcus faecalis, escherichia coli, e. coli o157:h7, helicobacter pylori, klebsiella pneumoniae, legionella pneumophila, listeria monocytogenes, pseudomonas aeruginosa, salmonella sp., and staphyloc ... | 2007 | 17462712 |
| canine cathelicidin (k9cath): gene cloning, expression, and biochemical activity of a novel pro-myeloid antimicrobial peptide. | cathelicidins, a group of cationic peptides found in leukocytes and epithelial cells, play a central role in the early innate immune defense against infection. although these host defense peptides have been reported in several mammalian species, including primates, no cathelicidins have been identified in carnivores. here we report the cloning, tissue expression and biological activity of a novel canine cathelicidin (k9cath). the full-length cdna sequence of k9cath encodes a predicted 172 amino ... | 2007 | 17462733 |
| development of matrix lysis for concentration of gram positive bacteria from food and blood. | the development of a fast, reliable and inexpensive protocol for the concentration of bacteria from food by the removal of fat, carbohydrates and proteins that is compatible with downstream alternative dna-based quantification methods is described. the protocol was used for dairy products, cooked and smoked fish and meat, carbohydrate-rich cooked products, ready-to-eat sauces, egg and blood. lysis resulted in pellets of reasonable size for further processing. starch, plant materials, fungi, tiss ... | 2007 | 17462766 |
| temperature-assisted pressure inactivation of listeria monocytogenes in turkey breast meat. | ready-to-eat turkey breast meat samples were surface-inoculated with a five-strain cocktail of listeria monocytogenes cultures to a final concentration of approximately 10(7) cfu/g. the inoculated meat samples were vacuum-packaged and pressure treated at 300 mpa for 2 min, 400 mpa for 1 min, and 500 mpa for 1 min at initial sample temperatures of 1, 10, 20, 30, 40, 50, and 55 degrees c. l. monocytogenes was most resistant to pressure at temperatures between 10 and 30 degrees c. as temperature de ... | 2007 | 17462773 |
| identification of new genes associated with intermediate resistance of enterococcus faecalis to divercin v41, a pediocin-like bacteriocin. | it has been suggested that resistance to class iia bacteriocins occurs at either a low or a high level. in listerial strains, low-level resistance (2-4-fold) to class iia bacteriocins is attributed to alterations in membrane lipid composition. in listeria monocytogenes and enterococcus faecalis, high-level resistance (1000-fold) correlates with inactivation of the mptacd operon, which encodes the eii(man)(t) mannose permease of the phosphotransferase system (pts). previous studies reported that ... | 2007 | 17464076 |
| hygienic quality of ewes' milk cheeses manufactured with artisan-produced lamb rennet pastes. | the use of artisan-produced lamb rennet pastes, but not any of the other commercial animal rennets, imparts a characteristic flavour to the cheese, so most mediterranean ewes' milk cheeses are coagulated with this kind of rennet paste. in contrast to the advantages of using lamb or kid rennet pastes from the sensory point of view, questions are still raised as to their hygienic quality. the goal was to examine the microbiological and enzymic quality of lamb rennet pastes prepared by cheese manuf ... | 2007 | 17466112 |
| innate immune activation of cd4 t cells in salmonella-infected mice is dependent on il-18. | production of ifn-gamma by cd4 t cells is generally thought to be mediated by tcr triggering, however, ag-nonspecific activation of effector cd8 t cells has been reported in infection models. in this study, we demonstrate that ag-experienced cd4 t cells in the spleen of salmonella-infected mice acquire the capacity to rapidly secrete ifn-gamma in response to stimulation with bacterial lysate or lps. this innate responsiveness of t cells was transient and most apparent during, and immediately fol ... | 2007 | 17475863 |
| evaluation of the international reference methods nf en iso 11290-1 and 11290-2 and an in-house method for the isolation of listeria monocytogenes from retail seafood products in france. | retail seafood products were analyzed on their use-by date using the international reference methods nf en iso 11290-1 and 11290-2 (collectively method r) or an in-house method (method b) for the isolation of listeria monocytogenes. the sensitivity of the methods was about 78%. method r detected more positive samples of smoked salmon and herb-flavored slices of smoked salmon than did method b, whereas the reverse was true for samples of carpaccio-like salmon, herb-flavored slices of raw salmon, ... | 2007 | 17477258 |
| antimicrobial effects of alginate-based films containing essential oils on listeria monocytogenes and salmonella typhimurium present in bologna and ham. | bologna and ham slices (300 of each) were inoculated with salmonella typhimurium or listeria monocytogenes at 10(3) cfu/cm(2). alginate-based edible films that had been immersed in a 2 or 20% (wt/vol) cac12 solution and contained 1% (wt/ vol) essential oils of spanish oregano (o; corydothymus capitatus), chinese cinnamon (c; cinnamomum cassia), or winter savory (s; satureja montana) were then applied to slices to control pathogen growth. on bologna, c-based films pretreated with 20% cac12 were t ... | 2007 | 17477259 |
| microbiological safety of retail vacuum-packed and modified-atmosphere-packed cooked meats at end of shelf life. | a study of retail modified-atmosphere-packed and vacuum-packed cooked ready-to-eat meats was undertaken from september through mid-november 2003 to determine the microbiological quality at the end of shelf life and to establish any risk factors in the production, storage, and display of this product. examination of 2,981 samples using microbiological guidelines criteria revealed that 66% were of satisfactory or acceptable microbiology quality, 33% were of unsatisfactory quality mainly due to hig ... | 2007 | 17477265 |
| development of thermal surrogate microorganisms in ground beef for in-plant critical control point validation studies. | in search of a suitable surrogate microorganism for in-plant critical control point validation, we compared the rates of thermal inactivation of three bacteria, enterococcus faecium b2354, pediococcus parvulus hp, and pediococcus acidilactici lp, to those of listeria monocytogenes and salmonella. ground beef samples containing 4 and 12% fat were inoculated with e. faecium, l. monocytogenes, and salmonella senftenberg 775w and heated at 58, 62, 65, or 68 degrees c. the decimal reduction times (d- ... | 2007 | 17477266 |
| inhibition of listeria monocytogenes using nisin with grape seed extract on turkey frankfurters stored at 4 and 10 degrees c. | recontamination of cooked ready-to-eat (rte) chicken and beef products with listeria monocytogenes has been a major safety concern. natural antimicrobials in combinations can be an alternative approach for controlling l. monocytogenes. therefore, the objectives of this study were to evaluate the inhibitory activities against l. monocytogenes of nisin (6,400 iu/ ml), grape seed extract (gse; 1%), and the combination of nisin and gse both in tryptic soy broth with 0.6% yeast extract (tsbye) and on ... | 2007 | 17477277 |
| evaluation in vitro of the antagonistic substances produced by lactobacillus spp. isolated from chickens. | to determine the inhibitory capacity of lactic acid bacteria due to the action of antagonistic substances, we tested 474 isolates of lactobacillus from the crop and cecum of chickens against gram-positive and gram-negative indicator microorganisms by the spot-on-the-lawn and well-diffusion antagonism methods. of the 474 isolates, 265 demonstrated antimicrobial activity against the indicator microorganisms. isolates identified as l. reuteri, l. salivarius, or lactobacillus spp. inhibited enteroco ... | 2007 | 17479773 |
| soluble metals in residual oil fly ash alter innate and adaptive pulmonary immune responses to bacterial infection in rats. | the soluble metals of the pollutant, residual oil fly ash (rofa), have been shown to alter pulmonary bacterial clearance in rats. the goal of this study was to determine the potential effects on both the innate and adaptive lung immune responses after bacterial infection in rats pre-exposed to the soluble metals in rofa. sprague-dawley rats were intratracheally dosed (i.t.) at day 0 with rofa (r-total) (1.0 mg/100 g body weight), the soluble fraction of rofa (r-soluble), the soluble sample subje ... | 2007 | 17481688 |
| listeria monocytogenes fecal shedding in dairy cattle shows high levels of day-to-day variation and includes outbreaks and sporadic cases of shedding of specific l. monocytogenes subtypes. | fecal shedding of listeria monocytogenes poses a risk for contamination of animal feed and agricultural environments and raw food at the pre-harvest stages of food production. to be able to reduce these risks it is critical to improve understanding of the epidemiology of l. monocytogenes shedding in feces. the objective of this study was to assess the daily variability of fecal shedding and its association with individual animal (lactation number and the day of current lactation) and environment ... | 2007 | 17481754 |
| listeria monocytogenes promotes tumor growth via tumor cell toll-like receptor 2 signaling. | the contribution of bacterial infection to tumorigenesis is usually ascribed to infection-associated inflammation. an alternate view is that direct interaction of bacteria with tumor cells promotes tumor progression. here, we show that the microenvironment of large tumors favors bacterial survival, which in turn directly accelerates tumor growth by activating tumor cell toll-like receptors (tlr). listeria monocytogenes (lm) survives in the microenvironment of large but not small tumors, resultin ... | 2007 | 17483348 |
| modification of chicken avian beta-defensin-8 at positively selected amino acid sites enhances specific antimicrobial activity. | antimicrobial peptides (amps), essential components of innate immunity, are found in a range of phylogenetically diverse species and are thought to act by disrupting the membrane integrity of microbes. in this paper, we used evolutionary signatures to identify sites that are most relevant during the functional evolution of these molecules and introduced amino acid substitutions to improve activity. we first demonstrate that the anti-microbial activity of chicken avian beta-defensin-8, previously ... | 2007 | 17483936 |
| a kinematic description of the trajectories of listeria monocytogenes propelled by actin comet tails. | the bacterial pathogen listeria monocytogenes propels itself in the cytoplasm of the infected cells by forming a filamentous comet tail assembled by the polymerization of the cytoskeletal protein actin. although a great deal is known about the molecular processes that lead to actin-based movement, most macroscale aspects of motion, including the nature of the trajectories traced out by the motile bacteria, are not well understood. here, we present 2d trajectories of listeria moving between a gla ... | 2007 | 17485664 |
| the 2-cys peroxiredoxin-deficient listeria monocytogenes displays impaired growth and survival in the presence of hydrogen peroxide in vitro but not in mouse organs. | resistance of listeria monocytogenes to reactive oxygen radicals may facilitate its survival in phagocytic cells and against some oxidizing sanitizers. the aim of this study was to investigate the function of the 2-cys peroxiredoxin (prx) homologue in l. monocytogenes, particularly its survival in a hydrogen peroxide-containing environment. an in-frame prx deletion mutant and a complementation strain were constructed and evaluated for their growth and survival either in media containing differen ... | 2007 | 17486404 |
| vapor-phase activities of cinnamon, thyme, and oregano essential oils and key constituents against foodborne microorganisms. | the aim of the study presented here was to gain knowledge about the vapor-phase antimicrobial activity of selected essential oils and their major putatively active constituents against a range of foodborne bacterial and fungal strains. in a first step, the vapor-phase antimicrobial activities of three commercially available essential oils (eos)-cinnamon (cinnamomum zeylanicum), thyme (thymus vulgaris), and oregano (origanum vulgare)-were evaluated against a wide range of microorganisms, includin ... | 2007 | 17488023 |
| rapid and sensitive magnetoelastic biosensors for the detection of salmonella typhimurium in a mixed microbial population. | in this article, we report the results of an investigation into the performance of a wireless, magnetoelastic biosensor designed to selectively detect salmonella typhimurium in a mixed microbial population. the langmuir-blodgett (lb) monolayer technique was employed for antibody (specific to salmonella sp.) immobilization on rectangular shaped strip magnetoelastic sensors (2 x 0.4 x 0.015 mm). bacterial binding to the antibody on the sensor surface changes the resonance parameters, and these cha ... | 2007 | 17490768 |
| comparative in vitro antimicrobial activity of tigecycline, a new glycylcycline compound, in freshly prepared medium and quality control. | the in vitro spectra of activity of tigecycline and tetracycline were determined for 2,490 bacterial isolates representing 50 different species or phenotypic groups. all isolates were tested simultaneously by broth microdilution using freshly prepared mueller-hinton broth and by disk diffusion. portions of these data were submitted to the food and drug administration (fda) in support of the sponsor's application for new drug approval. in a separate study, mic and disk diffusion quality control r ... | 2007 | 17494717 |
| plasma-mediated grafting of poly(ethylene glycol) on polyamide and polyester surfaces and evaluation of antifouling ability of modified substrates. | a simple cold plasma technique was developed to functionalize the surfaces of polyamide (pa) and polyester (pet) for the grafting of polyethylene glycol (peg) with the aim of reducing biofilm formation. the surfaces of pa and pet were treated with silicon tetrachloride (sicl4) plasma, and peg was grafted onto plasma-functionalized substrates (pa-peg, pet-peg). different molecular weights of peg and grafting times were tested to obtain optimal surface coverage by peg as monitored by electron spec ... | 2007 | 17500575 |
| interactions between circadian rhythm and immunity in drosophila melanogaster. | 2007 | 17502084 | |
| thrombospondin-1 promotes cellular adherence of gram-positive pathogens via recognition of peptidoglycan. | thrombospondin-1 (tsp1) is a matricellular glycoprotein that has key roles in interactions between human cells and components of the extracellular matrix. here we report a novel role for the lectin tsp1 in pathogen-host interactions. binding assays and flow cytometric analysis demonstrate that streptococcus pneumoniae and other gram-positive pathogens including s. pyogenes, staphylococcus aureus, and listeria monocytogenes interact specifically with human tsp1. we also show for the first time th ... | 2007 | 17507668 |
| herpesvirus latency confers symbiotic protection from bacterial infection. | all humans become infected with multiple herpesviruses during childhood. after clearance of acute infection, herpesviruses enter a dormant state known as latency. latency persists for the life of the host and is presumed to be parasitic, as it leaves the individual at risk for subsequent viral reactivation and disease. here we show that herpesvirus latency also confers a surprising benefit to the host. mice latently infected with either murine gammaherpesvirus 68 or murine cytomegalovirus, which ... | 2007 | 17507983 |
| listeria monocytogenes encephalitis mimicking herpes simplex virus encephalitis: the differential diagnostic importance of cerebrospinal fluid lactic acid levels. | listeria monocytogenes is a common cause of bacterial meningitis in elderly patients and in those with impaired cellular immunity. the most common central nervous system infection caused by l. monocytogenes is acute bacterial meningitis; meningoencephalitis is uncommon and encephalitis is rare. early diagnosis of l. monocytogenes meningitis is difficult because only 50% of cerebrospinal fluid (csf) gram stains are negative. l. monocytogenes is one of the few central nervous system pathogens asso ... | 2007 | 17509430 |
| lactoferrin from canine neutrophils: isolation and physicochemical and antimicrobial properties. | lactoferrin has been isolated from canine leukocytes for the first time. lactoferrin was identified by n-terminal amino acid sequence and by capability to capture ferric cations resulting in a complex with absorbance maximum at 460-470 nm. it is demonstrated that canine lactoferrin resembles the human homolog in some physicochemical properties, i.e. molecular weight, carbohydrate presence, and conditions of protein-iron complex dissociation. bactericidal activity of dog lactoferrin was demonstra ... | 2007 | 17511610 |
| spr biosensor for the detection of l. monocytogenes using phage-displayed antibody. | whole cells of listeria monocytogenes were detected with a compact, surface plasmon resonance (spr) sensor using a phage-displayed scfv antibody to the virulence factor actin polymerization protein (acta) for biorecognition. phage lm p4:a8, expressing the scfv antibody fused to the piii surface protein was immobilized to the sensor surface through physical adsorption. a locally constructed fluidics system was used to deliver solutions to the compact, two-channel spreeta sensor. specificity of th ... | 2007 | 17512186 |
| influence of treatment time and pulse frequency on salmonella enteritidis, escherichia coli and listeria monocytogenes populations inoculated in melon and watermelon juices treated by pulsed electric fields. | consumption of unpasteurized melon and watermelon juices has caused several disease outbreaks by pathogenic microorganisms worldwide. pulsed electric field (pef) has been recognized as a technology that may inactivate those bacteria present in fluid food products at low temperatures. hence, pef treatment at 35 kv/cm, 4 mus pulse duration in bipolar mode and square shape were applied on salmonella enteritidis, e. coli and l. monocytogenes populations inoculated in melon and watermelon juices with ... | 2007 | 17512997 |
| a virus-like particle-based vaccine selectively targeting soluble tnf-alpha protects from arthritis without inducing reactivation of latent tuberculosis. | neutralization of the proinflammatory cytokine tnf-alpha by mabs or soluble receptors represents an effective treatment for chronic inflammatory disorders such as rheumatoid arthritis, psoriasis, or crohn's disease. in this study, we describe a novel active immunization approach against tnf-alpha, which results in the induction of high titers of therapeutically active autoantibodies. immunization of mice with virus-like particles of the bacteriophage qbeta covalently linked to either the entire ... | 2007 | 17513796 |
| biophysical modeling of forward scattering from bacterial colonies using scalar diffraction theory. | a model for forward scattering from bacterial colonies is presented. the colonies of interest consist of approximately 10(12) - 10(13) individual bacteria densely packed in a configuration several millimeters in diameter and approximately 0.1-0.2 mm in thickness. the model is based on scalar diffraction theory and accounts for amplitude and phase modulation created by three macroscopic properties of the colonies: phase modulation due to the surface topography, phase modulation due to the radial ... | 2007 | 17514326 |
| cytolysin-dependent escape of the bacterium from the phagosome is required but not sufficient for induction of the th1 immune response against listeria monocytogenes infection: distinct role of listeriolysin o determined by cytolysin gene replacement. | listeria monocytogenes evades the antimicrobial mechanisms of macrophages by escaping from the phagosome into the cytosolic space via a unique cytolysin that targets the phagosomal membrane, listeriolysin o (llo), encoded by hly. gamma interferon (ifn-gamma), which is known to play a pivotal role in the induction of th1-dependent protective immunity in mice, appears to be produced, depending on the bacterial virulence factor. to determine whether the llo molecule (the major virulence factor of l ... | 2007 | 17517863 |
| [strategies for the development of new tuberculosis vaccines]. | tuberculosis remains a substantial global health problem causing 2 million deaths, and an estimated 8 to 10 million new infections a year. the efficacy of the mycobacterium bovis bacillus calmette-guérin (bcg), the only available antituberculosis vaccine, is variable (0-80%), especially in tuberculosis-endemic countries. over the past decade there has been a resurgence of interest in the development of new tuberculosis vaccines and some of the most promising are now entering into early clinical ... | 2007 | 17519853 |