Publications

factors associated with variation in bulk-tank-milk salmonella dublin elisa odc% in dairy herds.	our objective was to determine factors that contribute to variation in bulk-tank-milk salmonella dublin enzyme-linked immunosorbent assays (elisa) corrected optic-density measurements (odc%) in dairy herds. we constructed hierarchical mixed models with repeated bulk-tank-milk elisa odc% in 31 danish dairy herds. four models included different combinations of explanatory factors, and we compared how well these models described the variation in the data. herd was included as a random effect nested ...	2005	15820114
differential contribution of sodc1 and sodc2 to intracellular survival and pathogenicity of salmonella enterica serovar choleraesuis.	several of the most virulent salmonella enterica strains possess two genes encoding periplasmic cu,zn superoxide dismutase, sodc1 and sodc2, located on a lambdoid prophage and on the chromosome, respectively. these genes contribute to salmonella virulence by protecting bacteria from superoxide generated by the host's phagocytes. to investigate the respective contributions of sodc1 and sodc2 to the virulence of a clinical isolate of salmonella enterica serovar choleraesuis (s. choleraesuis), we h ...	2005	15823516
invasive infection with multidrug-resistant salmonella enterica serotype typhimurium definitive type 104 among hiv-infected adults.	multidrug-resistant salmonella enterica serotype typhimurium definitive type 104 (mrdt104), with resistance to at least ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (r-type acssut), was first detected in the united states in 1985, and the prevalence increased to account for nearly 7% of salmonella infections in 1998.	2005	15824994
multidrug-resistant shigella sonnei and salmonella enterica serotype typhimurium isolates producing ctx-m beta-lactamases as causes of community-acquired infection in france.		2005	15825010
purification and characterization of deacylated and/or palmitoylated lipid a species unique to salmonella enterica serovar typhimurium.	the salmonella enterica serovar typhimurium virulence gene products phop/phoq sense host microenvironments to regulate the expression of a lipid a 3-o-deacylase, pagl, and a lipid a palmitoyltransferase, pagp. therefore, deacylation and/or palmitoylation of lipid a could occur in salmonellae adapted to host environments. the phop/phoq-regulated modification of lipid a alters host recognition and signaling, and may play an important role in host defense against salmonellae infection. here we repo ...	2005	15826380
web-based investigation of multistate salmonellosis outbreak.	we investigated a large outbreak of salmonella enterica serotype javiana among attendees of the 2002 u.s. transplant games, including 1,500 organ transplant recipients. web-based survey methods identified pre-diced tomatoes as the source of this outbreak, which highlights the utility of such investigative tools to cope with the changing epidemiology of foodborne diseases.	2005	15829202
thermal resistance of salmonella enterica serotypes, listeria monocytogenes, and staphylococcus aureus in high solids liquid egg mixes.	decimal reduction times (d-values) were determined for salmonella enterica serotypes, listeria monocytogenes, and staphylococcus aureus in two high solids egg mixes designated a and b (water activity [a(w)] = 0.76 and 0.82; solids = 53.12 and 52.63%; ph = 5.09 and 5.29; viscosity = 183 and 119 centipoise/s, respectively) using a low-volume (0.06 ml) sealed glass capillary tube procedure. for salmonella, d-values ranged from 0.035 (70 degrees c) to 0.193 min (64 degrees c) in product a and from 0 ...	2005	15830659
inactivation of salmonella enterica serovar enteritidis on shell eggs by ozone and uv radiation.	the presence of salmonella enterica serovar enteritidis in shell eggs has serious public health implications. several treatments have been developed to control salmonella on eggs with mixed results. currently, there is a need for time-saving, economical, and effective egg sanitization treatments. in this study, shell eggs externally contaminated with salmonella (8.0 x 10(5) to 4.0 x 10(6) cfu/g of eggshell) were treated with gaseous ozone (o3) at 0 to 15 lb/in2 gauge for 0 to 20 min. in other ex ...	2005	15830660
growth of salmonella enterica serovar enteritidis in albumen and yolk contents of eggs inoculated with this organism onto the vitelline membrane.	by using an in vitro model simulating the potential opportunities for salmonella enterica serovar enteritidis (se) to proliferate within eggs contaminated with this organism following oviposition, we investigated growth of se in eggs. seventy to 140 cfu of one of three se strains originating either from egg contents, chicken meat, or a human infection were experimentally inoculated onto the vitelline membrane of eggs collected from specific-pathogen-free flocks of chickens and incubated at 25 de ...	2005	15830661
destruction of salmonella senftenberg on the shells of intact eggs by thermoultrasonication.	the combined effect of ultrasonic waves and heat treatment applied simultaneously was evaluated on the survival of strains of salmonella senftenberg on shells of intact eggs. this combined process has a higher killing effect than heat treatment alone. the decimal reduction times (d-values) were decreased by 65.2 to 11.1% in the temperature range studied (57.8 to 67 degrees c). in contrast to the effect on salmonella enterica serovar enteritidis in a previous study, thermoultrasonication had no i ...	2005	15830681
effectiveness of trisodium phosphate treatment against pathogenic and spoilage bacteria on poultry during refrigerated storage.	to determine the efficacy of trisodium phosphate (tsp) against pathogenic and spoilage bacteria on poultry and to assess the influence of the bacterial combination of inoculum on tsp effect, chicken legs were coinoculated with similar concentrations of a pathogenic (salmonella enterica ser. enteritidis or listeria monocytogenes) and a spoilage (pseudomonas fluorescens or brochothrix thermosphacta) bacteria. samples were dipped in tsp (12%, 15 min) or were not treated (control). microbiological a ...	2005	15830686
a randomized comparison of oral chloramphenicol versus ofloxacin in the treatment of uncomplicated typhoid fever in laos.	we conducted a randomized open trial of oral chloramphenicol (50mg/kg/day in four divided doses for 14 days) versus ofloxacin (15 mg/kg/day in two divided doses for 3 days) in 50 adults with culture-confirmed uncomplicated typhoid fever in vientiane, laos. patients had been ill for a median (range) of 8 (2-30) days. all salmonella enterica serotype typhi isolates were nalidixic acid-sensitive, four (8%) were chloramphenicol-resistant and three (6%) were multidrug-resistant. median (range) fever ...	2005	15837357
precise excision and secondary transposition of tnphoa in non-motile mutants of a salmonella enterica serovar enteritidis clinical isolate.	mutagenesis with tnphoa has been widely used in many bacteria. here, we report the excision and secondary transposition of this transposon in three non-motile (flic, flif and motb) mutants of salmonella enterica serovar enteritidis (s. enteritidis). isolation of motile revertants showed that they were kanamycin resistant and conserved a copy of tnphoa in their genome in an insertion site different from the initial one. they also expressed an intact flagella. characterization of the motile revert ...	2005	15837381
functional characterization of waal, a ligase associated with linking o-antigen polysaccharide to the core of pseudomonas aeruginosa lipopolysaccharide.	the o antigen of pseudomonas aeruginosa b-band lipopolysaccharide is synthesized by assembling o-antigen-repeat units at the cytoplasmic face of the inner membrane by nonprocessive glycosyltransferases, followed by polymerization on the periplasmic face. the completed chains are covalently attached to lipid a core by the o-antigen ligase, waal. in p. aeruginosa the process of ligating these o-antigen molecules to lipid a core is not clearly defined, and an o-antigen ligase has not been identifie ...	2005	15838026
polyphosphate kinase protects salmonella enterica from weak organic acid stress.	mutants of salmonella enterica lacking polyphosphate kinase (ppk) grow poorly in the presence of the weak organic acids acetate, propionate, and benzoate. this sensitivity is corrected by methionine and seems to result from destabilization of meta (homoserine transsuccinylase), the first enzyme in methionine biosynthesis. the meta protein is known to be sensitive to thermal inactivation, and ppk mutants are more sensitive to heat-induced methionine auxotrophy. peroxide increases the sensitivity ...	2005	15838036
exopolysaccharide sugars contribute to biofilm formation by salmonella enterica serovar typhimurium on hep-2 cells and chicken intestinal epithelium.	recently, we demonstrated that salmonella enterica serovar typhimurium can form biofilm on hep-2 cells in a type 1 fimbria-dependent manner. previous work on salmonella exopolysaccharide (eps) in biofilm indicated that the eps composition can vary based upon the substratum on which the bacterial biofilm forms. we have investigated the role of genes important in the production of colanic acid and cellulose, common components of eps. a mutation in the colanic acid biosynthetic gene, wcam, was intr ...	2005	15838049
a reduced level of charged trnaargmnm5ucu triggers the wild-type peptidyl-trna to frameshift.	frameshift mutations can be suppressed by a variety of differently acting external suppressors. the +1 frameshift mutation hisc3072, which has an extra g in a run of gs, is corrected by the external suppressor mutation suff44. we have shown that suff44 and five additional allelic suppressor mutations are located in the gene argu coding for the minor trnaargmnm5ucu and alter the secondary and/or tertiary structure of this trna. the c61u, g53a, and c32u mutations influence the stability, whereas t ...	2005	15840821
macrophage cell death due to salmonella enterica serovar typhi and its acid stress protein has features of apoptosis.	salmonella spp. have been shown to cause apoptosis of various host cell types as a part of their infection process. however, the induction of apoptosis remains to be looked into under the different host environments including acidic stress experienced by the pathogen. in order to simulate the in vivo acidic conditions, we studied the potential of s. typhi and its protein expressed under in vitro acidic conditions to induce apoptosis in macrophages. murine macrophages were isolated and interacted ...	2005	15840957
genetic and molecular analysis of gogb, a phage-encoded type iii-secreted substrate in salmonella enterica serovar typhimurium with autonomous expression from its associated phage.	salmonella enterica serovar typhimurium is lysogenized by several temperate bacteriophages that encode lysogenic conversion genes, which can act as virulence factors during infection and contribute to the genetic diversity and pathogenic potential of the lysogen. we have investigated the temperate bacteriophage called gifsy-1 in s.enterica serovar typhimurium and show here that the product of the gogb gene encoded within this phage shares similarity with proteins from other gram-negative pathoge ...	2005	15843015
eliminating the carriage of salmonella enterica serovar enteritidis in domestic fowls by feeding activated charcoal from bark containing wood vinegar liquid (nekka-rich).	the protective efficacy of activated charcoal containing wood vinegar liquid (nekka-rich) against intestinal infection with salmonella enterica serovar enteritidis was sought. in the present study, the adsorption effects of activated charcoal of nekka-rich on s. enteritidis and normal bacterial flora in the intestine, enterococcus faecium, were examined. s. enteritidis was effectively adsorbed by activated charcoal of nekka-rich. on the other hand, activated charcoal of nekka-rich showed lower b ...	2005	15844805
emergence of salmonella epidemics: the problems related to salmonella enterica serotype enteritidis and multiple antibiotic resistance in other major serotypes.	two major changes in the epidemiology of salmonellosis occurred in the second half of the 20th century: the emergence of food-borne human infections caused by s. enteritidis and by multiple-antibiotic resistant strains of salmonella. this review updates information on the s. enteritidis pandemic and focuses on the emergence of salmonella, carrying the sgi1 antibiotic resistance gene cluster, resistant to extended-spectrum cephalosporins, or resistant to fluoroquinolones. the factors responsible ...	2005	15845226
characterization of salmonella-induced cell death in human macrophage-like thp-1 cells.	salmonella strains are facultative intracellular pathogens that produce marked cytopathology during infection of host cells. different forms of cytopathic effects have been associated with the virulence systems encoded by the two salmonella pathogenicity islands (spi-1 and spi-2) and the spv locus. we used salmonella enterica serovar dublin to investigate the induction of cytopathology during infection of the human macrophage-like cell line thp-1. analysis of host cells by flow cytometry using a ...	2005	15845488
gamma irradiation or cd4+-t-cell depletion causes reactivation of latent salmonella enterica serovar typhimurium infection in c3h/hen mice.	upon infection with salmonella, a host develops an immune response to limit bacterial growth and kill and eliminate the pathogen. salmonella has evolved mechanisms to remain dormant within the body, only to reappear (reactivate) at a later time when the immune system is abated. we have developed an in vivo model for studying reactivation of salmonella enterica serovar typhimurium infection in mice. upon subcutaneous infection, c3h/hen (ity(r)) mice showed an increase in bacterial numbers in live ...	2005	15845491
differential induction of the toll-like receptor 4-myd88-dependent and -independent signaling pathways by endotoxins.	the biological response to endotoxin mediated through the toll-like receptor 4 (tlr4)-md-2 receptor complex is directly related to lipid a structure or configuration. endotoxin structure may also influence activation of the myd88-dependent and -independent signaling pathways of tlr4. to address this possibility, human macrophage-like cell lines (thp-1, u937, and mm6) or murine macrophage raw 264.7 cells were stimulated with picomolar concentrations of highly purified endotoxins. harvested supern ...	2005	15845500
infection of the reproductive tract and eggs with salmonella enterica serovar pullorum in the chicken is associated with suppression of cellular immunity at sexual maturity.	salmonella enterica serovar pullorum causes persistent infections in laying hens. splenic macrophages are the main site of persistence. at sexual maturity, numbers of bacteria increase and spread to the reproductive tract, which may result in vertical transmission to eggs or chicks. in this study we demonstrate that both male and female chickens may develop a carrier state following infection but that the increases in bacterial numbers and spread to the reproductive tract are phenomena restricte ...	2005	15845505
requirement of mgtc for brucella suis intramacrophage growth: a potential mechanism shared by salmonella enterica and mycobacterium tuberculosis for adaptation to a low-mg2+ environment.	a brucella suis mgtc mutant is defective for growth within macrophages and in low-mg(2+) medium. these phenotypes are strikingly similar to those observed with mgtc mutants from salmonella enterica and mycobacterium tuberculosis, two other pathogens that proliferate within phagosomes. mgtc appears as a remarkable virulence factor that would have been acquired by distantly related intracellular pathogens to contribute to the adaptation to a low-mg(2+) environment in the phagosome.	2005	15845525
mccj25 c-terminal is involved in rna-polymerase inhibition but not in respiration inhibition.	microcin j25 appears to have two intracellular targets: (1) rna polymerase, which was described in escherichia coli and salmonella enterica serovars, and (2) cell respiration in salmonella enterica serovars. c-terminal glycine amidation of the threaded segment localized in the mccj25 lariat ring region specifically blocked the rna-polymerase inhibition, but not the cell respiration inhibition and peptide uptake. these results suggest that different regions of the molecule are responsible for eac ...	2005	15850794
systemic administration of attenuated salmonella choleraesuis in combination with cisplatin for cancer therapy.	some anaerobic and facultative anaerobic bacteria have been employed as anticancer agents. previously, we have demonstrated tumor-targeting and antitumor activities of attenuated salmonella choleraesuis carrying antiangiogenic genes. here we exploited s. choleraesuis as a single-agent therapy and as part of a combination therapy with low-dose cisplatin for syngeneic murine lung tumor and hepatoma. systemically injected s. choleraesuis preferentially accumulated within tumors for at least 4 weeks ...	2005	15851009
compensatory role of pspa, a member of the phage shock protein operon, in rpoe mutant salmonella enterica serovar typhimurium.	sigma(e) is an alternative sigma factor that responds to and ameliorates extracytoplasmic stress. in salmonella enterica serovar typhimurium (s. typhimurium), sigma(e) is required for oxidative stress resistance, stationary-phase survival and virulence in mice. microarray analysis of stationary-phase gene expression in rpoe mutant bacteria revealed a dramatic increase in expression of pspa, a member of the phage shock protein (psp) operon. the psp operon can be induced by filamentous bacteriopha ...	2005	15853886
genetic environment and expression of the extended-spectrum beta-lactamase blaper-1 gene in gram-negative bacteria.	the genetic location of the gene coding for the expanded-spectrum beta-lactamase per-1 was analyzed in a series of gram-negative isolates. it was identified as part of a composite transposon bracketed by two novel insertion elements, ispa12 and ispa13, belonging to the is4 family that possess transposases that share 63% amino acid identity and that are chromosomally located in pseudomonas aeruginosa, providencia stuartii, and acinetobacter baumannii. on the contrary, the bla(per-1) gene was iden ...	2005	15855485
application of an in vitro infection model and simulation for reevaluation of fluoroquinolone breakpoints for salmonella enterica serotype typhi.	salmonella enterica serotype typhi and nontyphoidal salmonella remain major causes of morbidity and mortality worldwide. ampicillin, trimethoprim-sulfamethoxazole, and chloramphenicol no longer provide reliable coverage of salmonella, and fluoroquinoloes have emerged as first-line treatment options. due to mounting evidence of decreased in vitro susceptibility and diminished clinical response to fluoroquinolone therapy, it has been suggested that the nccls breakpoints for the salmonellae be reev ...	2005	15855495
salmonella enterica serovar infantis producing a ctx-m-9 beta-lactamase.		2005	15855550
a "gain of function" mutation in a protein mediates production of novel modified nucleosides.	the mutation sufy204 mediates suppression of a +1 frameshift mutation in the histidine operon of salmonella enterica serovar typhimurium and synthesis of two novel modified nucleosides in trna. the sufy204 mutation, which results in an amino-acid substitution in a protein, is, surprisingly, dominant over its wild-type allele and thus it is a "gain of function" mutation. one of the new nucleosides is 5-methylaminomethyl-2-thiouridine (mnm(5)s(2)u34) modified by addition of a c(10)h(17) side chain ...	2005	15861125
variable abattoir conditions affect salmonella enterica prevalence and meat quality in swine and pork.	research suggests that abattoir holding pens pose significant salmonella enterica risk to swine immediately preharvest. the goal of this study was to evaluate those factors related to holding that increased the prevalence of s. enterica in swine at slaughter. to accomplish this goal, we focused on holding time and flooring. our objectives were to (1) compare salmonella enterica prevalence among pigs held for short (15-45 min) versus long (up to 4 h) periods before slaughter; and (2) determine th ...	2005	15992301
vertical and horizontal transmission of salmonella within integrated broiler production system.	salmonella remains one of the leading causes of food-borne illness in the united states, and many key questions regarding the introduction and persistence in animal production systems still remain. in order to understand the ecology of salmonella within an integrated commercial broiler production system, 289 salmonella enterica were recovered from two integrated poultry farms during the production and processing of seven consecutive flocks. the variety and prevalence of salmonella serotypes diff ...	2005	15992303
genotypes and antibiotic resistance of salmonella newport isolates from u.s. market oysters.	the consumption of raw oysters contributes to food-borne diseases such as salmonellosis. prevalence studies in our laboratory have shown that salmonella spp. were present in 7.4% of u.s. market oysters, with the majority (78/101) of isolates being of the salmonella enterica newport serovar. e-tests were performed to assess the susceptibility of the s. newport oyster isolates to antibiotics used for treatment of salmonella infections. the oyster isolates were susceptible to gentamicin, trimethopr ...	2005	15992305
oral administration of a live aro attenuated salmonella vaccine strain expressing 14-kda schistosoma mansoni fatty acid-binding protein induced partial protection against experimental schistosomiasis.	we report the oral vaccination of swiss mice with an aro attenuated salmonella enterica var. typhimurium vaccine strain expressing the 14-kda schistosoma mansoni antigen, sm14. bacterial adjuvants, including (i) lactococcus lactis expressing interleukin-12 (il-12) and (ii) lactobacillus delbrueckii ufv-h2b20, were also employed in oral immunization assays. detection assays to specific igg and iga anti-sm14 antibodies were performed to evaluate humoral immune responses in vaccinated mice. an incr ...	2005	15993833
the genome of salmonella enterica serovar gallinarum: distinct insertions/deletions and rare rearrangements.	salmonella enterica serovar gallinarum is a fowl-adapted pathogen, causing typhoid fever in chickens. it has the same antigenic formula (1,9,12:--:--) as s. enterica serovar pullorum, which is also adapted to fowl but causes pullorum disease (diarrhea). the close relatedness but distinct pathogeneses make this pair of fowl pathogens good models for studies of bacterial genomic evolution and the way these organisms acquired pathogenicity. to locate and characterize the genomic differences between ...	2005	15995186
the novel oral typhoid vaccine m01zh09 is well tolerated and highly immunogenic in 2 vaccine presentations.	m01zh09 (salmonella enterica serovar typhi [ty2 aroc(-) ssav(-)] zh9) is a live oral-dose typhoid vaccine candidate. m01zh09 was rationally modified with 2 independently attenuating mutations, including a novel mutation in salmonella pathogenicity island (spi)-2. we demonstrate that m01zh09, in a single oral dose, is well tolerated and prompts broad immune responses, regardless of whether prevaccination with a bicarbonate buffer is given.	2005	15995948
extended-spectrum beta-lactamases in non-typhoidal salmonella spp. isolated in the uk are now a reality: why the late arrival?	in february 2004, we reported the first recognition of the presence of an extended-spectrum beta-lactamase (esbl) in non-typhoidal salmonella spp. in the uk; the beta-lactamase was tem-52. six months later, an shv-derived esbl (shv-12) was detected in a salmonella strain isolated in york and 6 months after that we have just identified ctx-m-type beta-lactamases in scottish isolates of salmonella enterica subsp. enterica serovar typhimurium and salmonella virchow (unpublished results). a very rec ...	2005	16000403
ceftriaxone resistance of nontyphoidal salmonella enterica isolates in northern taiwan attributable to production of ctx-m-14 and cmy-2 beta-lactamases.	among 3,027 nontyphoidal salmonella enterica isolates identified between january 1999 and december 2002 in a medical center in northern taiwan, 31 were resistant to the extended-spectrum cephalosporin ceftriaxone (1.02% [31/3,027]), including 2 in 1999 (0.36% [2/549]), 13 in 2000 (1.49% [13/870]), 7 in 2001 (0.78% [7/893]), and 9 in 2002 (1.26% [9/715]). sixteen of these isolates belonged to salmonella serogroup b, nine belonged to serogroup c, four belonged to serogroup d, and two belonged to s ...	2005	16000441
development of a novel protein microarray method for serotyping salmonella enterica strains.	an antibody microarray assay was developed for salmonella serotyping based on the kauffmann-white scheme. a model (8 by 15) array was constructed using 35 antibodies for identification of 20 common salmonella serovars and evaluated using 117 target and 73 nontarget salmonella strains. the assay allowed complete serovar identification of 86 target strains and partial identification of 30 target strains and allowed exclusion of the 73 nontarget strains from the target serovars.	2005	16000469
repeated occurrence of diverse extended-spectrum beta-lactamases in minor serotypes of food-borne salmonella enterica subsp. enterica.	screening of greek nontyphoid salmonellae from 2000 to 2002 yielded three extended-spectrum beta-lactamase (esbl)-producing human isolates. salmonella enterica serotype brandenburg harbored a multiresistant shv-5 gene-carrying plasmid. s. enterica serotype blockley and s. enterica serotype hadar harbored a tem-52 gene-carrying plasmid. an s. enterica serotype virchow strain producing plasmid-mediated ctx-m-32 was isolated twice from poultry end products. all esbl plasmids were self-transferable ...	2005	16000476
nosocomial outbreak of pediatric gastroenteritis caused by ctx-m-14-type extended-spectrum beta-lactamase-producing strains of salmonella enterica serovar london.	ctx-m-14-type extended-spectrum beta-lactamase was first detected in salmonella enterica serovar london strains which were isolated from three hospitalized pediatric patients with gastroenteritis. the isolates had pulsed-field gel electrophoresis patterns identical to those of the previously isolated antimicrobial-susceptible strains from community-acquired gastroenteritis, suggesting the susceptible clone acquired the resistance.	2005	16000495
shifts from glucose to certain secondary carbon-sources result in activation of the extracytoplasmic function sigma factor sigmae in salmonella enterica serovar typhimurium.	salmonella enterica serovar typhimurium (s. typhimurium) elicits the starvation-stress response (ssr) due to starvation for an essential nutrient, e.g. a carbon/energy source (c-source). as part of the ssr, the alternative sigma factor sigma(e) is activated and induced. the authors suspect that this activation is, in part, triggered by changes in the s. typhimurium cell envelope occurring during the adaptation from growth to carbon/energy starvation (c-starvation), and resulting in an increased ...	2005	16000727
ousb, a broad-specificity abc-type transporter from erwinia chrysanthemi, mediates uptake of glycine betaine and choline with a high affinity.	the ability of erwinia chrysanthemi to cope with environments of elevated osmolality is due in part to the transport and accumulation of osmoprotectants. in this study we have identified a high-affinity glycine betaine and choline transport system in e. chrysanthemi. by using a pool of tn5-b21 ousa mutants, we isolated a mutant that could grow in the presence of a toxic analogue of glycine betaine (benzyl-glycine betaine) at high osmolalities. this mutant was impaired in its ability to transport ...	2005	16000740
prevalence and antimicrobial resistance of campylobacter spp. and salmonella serovars in organic chickens from maryland retail stores.	retail organic (n = 198) and conventional (n = 61) chickens were analyzed. most organic (76%) and conventional (74%) chickens were contaminated with campylobacters. salmonellae were recovered from 61% of organic and 44% of conventional chickens. all salmonella enterica serovar typhimurium isolates from conventional chickens were resistant to five or more antimicrobials, whereas most s. enterica serovar typhimurium isolates (79%) from organic chickens were susceptible to 17 antimicrobials tested.	2005	16000828
vector-primed mice display hypo-responsiveness to foreign antigen presented by recombinant salmonella regardless of the route of delivery.	our previous studies have shown that mice which have been orally primed with an attenuated salmonella vector [s. enterica serovar stanley] are hypo-responsive to foreign antigens later delivered orally by the same vector strain, responding with significantly impaired serum and intestinal antibody responses compared with those seen in unprimed controls. initial vector priming of the gut-associated lymphoid tissue (galt) is likely to result in impaired persistence of recombinant salmonella later a ...	2005	16002258
cpg oligonucleotides partially inhibit growth of mycobacterium tuberculosis, but not salmonella or listeria, in human monocyte-derived macrophages.	immunostimulatory dna sequences and their synthetic oligonucleotide analogs (cpg-odn) activate innate immunity and can stimulate antibacterial effects against numerous intracellular pathogens. while it has been shown previously that cpg-odn inhibit growth of mycobacterium avium in murine and human macrophages, we now report that mycobacterium tuberculosis growth can be inhibited by cpg-odn treatment of human monocyte-derived macrophages (hmdm). this inhibitory effect was reversed by ifn-gamma, w ...	2005	16002269
insertional mutation of mara vitiates inducible multiple antimicrobial resistance in salmonella enterica subsp. enterica serovar choleraesuis.	mara has been shown to mediate a multiple antimicrobial resistance (mar) phenotype following induction in some members of the enterobacteriaceae. when salmonella choleraesuis was exposed to inducing agents they displayed higher minimal inhibitory concentrations (mic) to multiple antimicrobial agents and an increase in mara expression as determined by northern hybridization analysis. the objective of the present study was to determine if mutation of mara vitiated multiple antimicrobial resistance ...	2005	16006078
epidemiologic evaluation of diarrhea in dogs in an animal shelter.	to determine associations among infectious pathogens and diarrheal disease in dogs in an animal shelter and demonstrate the use of geographic information systems (giss) for tracking spatial distributions of diarrheal disease within shelters.	2005	16008226
probing the properties of lipopolysaccharide monolayers and their interaction with the antimicrobial peptide polymyxin b by atomic force microscopy.	in contrast to the majority of all known cell types, gram-negative bacteria have a second membrane, the outer membrane, which is an asymmetric bilayer composed of a phospholipid inner leaflet and a glycolipid outer leaflet. the glycolipid layer, in most cases being composed of a lipopolysaccharide (lps), is the first target for antimicrobial agents. to get a basic understanding of the membrane-forming properties of lps, we reconstituted monolayers of deep rough mutant lps from salmonella enteric ...	2005	16008411
outbreaks of salmonellosis at elementary schools associated with dissection of owl pellets.	salmonella enterica serotype typhimurium outbreaks occurred at two elementary schools after science club students dissected owl pellets. forty primary cases were identified (26 culture-confirmed). at the first school, pellets were dissected on a cafeteria table, concurrent with after-school child care in the cafeteria. subsequently, the table was not sanitized before use by after-school care students for snack, or before the next school lunch. at the second school, pellets were dissected in a de ...	2005	16011429
activation of murine dendritic cells and macrophages induced by salmonella enterica serovar typhimurium.	macrophages and dendritic cells (dcs) are antigen-presenting cells (apcs), and the direct involvement of both cell types in the immune response to salmonella has been identified. in this study we analysed the phenotypic and functional changes that take place in murine macrophages and dcs in response to live and heat-killed salmonella enterica serovar typhimurium. both types of cell secreted proinflammatory cytokines and nitric oxide (no) in response to live and heat-killed salmonellae. bacterial ...	2005	16011515
persistence of orally administered salmonella enterica serovars agona and montevideo in atlantic salmon (salmo salar l.).	the objective of our experiments was to study the persistence and dissemination of orally administered salmonella in smoltified atlantic salmon. in experiment 1, salmon kept at 15 degrees c were fed for 1 week with feed contaminated with 96 most-probable-number units of salmonella agona per 100 g of feed and then starved for 2 weeks. samples were taken from the gastrointestinal tract and examined for salmonella 1, 2, 8, 9, 15, and 16 days after the feeding ended. in experiment 2, salmonella agon ...	2005	16013367
effect of relative humidity on preharvest survival of bacterial and viral pathogens on the surface of cantaloupe, lettuce, and bell peppers.	the purpose of this study was to compare the effects of humidity on the preharvest survival of microbial pathogens on cantaloupe, lettuce, and bell peppers. an additional goal was to evaluate clostridium perfringens as an indicator of fecal contamination on produce. the microorganisms used in this study included escherichia coli, e. coli o157:h7, shigella sonnei, salmonella enterica subsp. enterica, clostridium perfringens, hepatitis a virus (hav), feline calicivirus (fcv), and coliphage prd1. t ...	2005	16013370
food safety knowledge of consumers and the microbiological and temperature status of their refrigerators.	the objectives of this study were to examine domestic food safety knowledge levels of consumers, establish the levels and incidence of bacterial contamination and operational temperatures in domestic refrigerators, and identify areas in which consumer food safety education is necessary in ireland. a food safety knowledge questionnaire applied to a representative sample of households (n = 1,020) throughout the island of ireland found the gaps in consumer food safety knowledge. analysis of swab sa ...	2005	16013380
the effect of type-1 fimbrial immunization on gut pathophysiological response in rats infected with salmonella enterica subsp. enterica serovar typhimurium.	the pathophysiological mechanism of salmonella enterica subsp. enterica serovar typhimurium (salmonella typhimurium) induced gastroenteritis is controlled by interplay of various cell signaling events. adherence of this organism through type-1 fimbriae is known to be a vital prerequisite for the establishment of infection. in the present investigation male albino wistar rats were immunized with purified type-1 fimbriae and challenged intragastrically with s. typhimurium. electrolyte transport an ...	2005	16013447
analysis of the role of hp0208, a phase-variable open reading frame, and its homologues hp1416 and hp0159 in the biosynthesis of helicobacter pylori lipopolysaccharide.	the roles of the three orfs hp0208, hp0159 and hp1416 in the biosynthesis of helicobacter pylori 26695 lps were investigated in this study. these orfs represent a paralogous family of genes with homology to the salmonella enterica serovar typhimurium (hereafter referred to as s. typhimurium) waaj gene, which encodes an alpha-1,2-glycosyltransferase required for core lps biosynthesis. hp0208 contains multiple tandem repeats of the dimer 5'ga at its 5' end and its expression is predicted to be sub ...	2005	16014421
salmonella agona outbreak from contaminated aniseed, germany.	a nationwide outbreak of salmonella agona caused by aniseed-containing herbal tea occurred from october 2002 through july 2003 among infants in germany. consumers should adhere strictly to brewing instructions, although in exceptional cases this precaution may not be protective, particularly when preparing tea for vulnerable age groups.	2005	16022796
differential responses of macrophages to salmonella enterica serovars enteritidis and typhimurium.	macrophages are major effectors against salmonella infection, and also transport bacteria between host tissues and provide a protected site for intracellular bacterial replication. we hypothesized that differences in chicken macrophage responses to salmonella enterica serovar enteritidis (se) and serovar typhimurium (st) played a role in preferential infection of eggs by se compared with st. to test this hypothesis, we determined bacterial phagocytosis and intracellular viability and macrophage ...	2005	16023220
salmonella stress management and its relevance to behaviour during intestinal colonisation and infection.	the enteric pathogen salmonella enterica is exposed to a number of stressful environments during its life cycle within and outside its various hosts. during intestinal colonisation salmonella is successively exposed to acid ph in the stomach, to the detergent-like activity of bile, to decreasing oxygen supply, to the presence of multiple metabolites produced by the normal gut microflora and finally it is exposed to cationic antimicrobial peptides present on the surface of epithelial cells. there ...	2005	16023758
physical mapping of eight pig genes whose expression level is acutely affected by salmonella challenge.		2005	16026354
proteome analysis of serovars typhimurium and pullorum of salmonella enterica subspecies i.	salmonella enterica subspecies i includes several closely related serovars which differ in host ranges and ability to cause disease. the basis for the diversity in host range and pathogenic potential of the serovars is not well understood, and it is not known how host-restricted variants appeared and what factors were lost or acquired during adaptations to a specific environment. differences apparent from the genomic data do not necessarily correspond to functional proteins and more importantly ...	2005	16026608
unexpected functional diversity among fadr fatty acid transcriptional regulatory proteins.	the fadr protein of escherichia coli has been shown to play a dual role in transcription of the genes of bacterial fatty acid metabolism. the protein acts as a repressor of beta-oxidation and an activator of unsaturated fatty acid synthesis. fadr dna binding is antagonized by long chain acyl-coas, and thus fadr acts as a sensor of fatty acid availability in the environment. when viewed from a genomic viewpoint, fadr proteins are unusual in that the dna binding domain is very highly conserved amo ...	2005	16027119
the holin protein of bacteriophage prd1 forms a pore for small-molecule and endolysin translocation.	prd1 is a bacteriophage with an icosahedral outer protein layer surrounding the viral membrane, which encloses the linear double-stranded dna genome. prd1 infects gram-negative cells harboring a conjugative incp plasmid. here we studied the lytic functions of prd1. using infected cells and plasmid-borne lysis genes, we demonstrated that a two-component lysis system (holin-endolysin) operates to release progeny phage particles from the host cell. monitoring of ion fluxes and the atp content of th ...	2005	16030234
enhancement of endotoxin neutralization by coupling of a c12-alkyl chain to a lactoferricin-derived peptide.	antibacterial peptide acylation, which mimics the structure of the natural lipopeptide polymyxin b, increases antimicrobial and endotoxin-neutralizing activities. the interaction of the lactoferricin-derived peptide lf11 and its n-terminally acylated analogue, lauryl-lf11, with different chemotypes of bacterial lipopolysaccharide (lps re, ra and smooth s form) was investigated by biophysical means and was related to the peptides' biological activities. both peptides exhibit high antibacterial ac ...	2005	15344905
systemic administration of attenuated salmonella choleraesuis carrying thrombospondin-1 gene leads to tumor-specific transgene expression, delayed tumor growth and prolonged survival in the murine melanoma model.	some anaerobic and facultative anaerobic bacteria have been used experimentally as anticancer agents because of their selective growth in the hypoxia regions of solid tumors after systemic administration. we have previously shown the feasibility of using attenuated salmonella choleraesuis as a gene delivery vector. in this study, we exploited s. choleraesuis carrying thrombospondin-1 (tsp-1) gene for treating primary melanoma and experimental pulmonary metastasis in the syngeneic murine b16f10 m ...	2005	15375381
depletion of apolipoprotein n-acyltransferase causes mislocalization of outer membrane lipoproteins in escherichia coli.	lipoproteins in gram-negative enterobacteriaceae carry three fatty acids on the n-terminal cysteine residue, two as a diacylglyceride and one through an n-linkage following signal peptide cleavage. most lipoproteins are anchored in the outer membrane, facing the periplasm, but some lipoproteins remain in the plasma membrane, depending on the amino acid at position +2, immediately after the fatty-acylated cysteine. in vitro, the last step in lipoprotein maturation, n-acylation of apolipoproteins ...	2005	15513925
cloning of porcine triggering receptor expressed on myeloid cells-1 (trem-1) and its induction by lipopolysaccharide, peptidoglycan, and salmonella enterica serovar typhimurium infection.	triggering receptors expressed on myeloid cells (trem) are a family of activating receptors expressed on neutrophils and monocytes. these receptors are involved in regulation of immunity by inducing the expression of inflammatory cytokines and adhesion molecules, augmenting dendritic cell maturation, and are implicated in septic shock. here we report the cloning of full-length trem cdna from porcine bone marrow cells, which predicts a 238 amino-acid peptide. treating porcine bone marrow cells wi ...	2005	15325519
isolation of salmonella spp. from liquid and solid excreta prior to and following ensilage in ten swine farms located in central mexico.	a study was carried out to define selected bacteriological characteristics of residues from 10 swine farms, 5 with or without prior clinical enteric disease (pced) and to determine the effect of ensilage on the bacteria present in the solid fraction. at each farm, samples were taken from the sedimentation basin (sb), the solid fraction (sf), and the liquid fraction (lf). for each sample, cfu/g for enteric bacteria were quantified; salmonella spp. were isolated and typified. solid phase samples f ...	2005	15501666
signal-dependent binding of the response regulators phop and pmra to their target promoters in vivo.	low mg2+ promotes phosphorylation of the response regulators phop and pmra and transcription of their activated genes in salmonella enterica. using chromatin immunoprecipitation, we have now determined that the phop and pmra proteins are recruited to the regulatory region of their target genes when bacteria experience low mg2+ but not when they are grown in high mg2+. even when the phop protein was artificially produced at 4-fold higher levels than the wild-type strain, promoter occupancy requir ...	2005	15569664
the salmonella enterica serovar typhimurium-encoded type iii secretion systems can translocate chlamydia trachomatis proteins into the cytosol of host cells.	chlamydia trachomatis is an obligate, intracellular pathogen that is a major cause of preventable blindness and infertility worldwide. although the published genome sequence suggests that c. trachomatis encodes a type iii secretion system, the lack of genetic tools for studying chlamydia has hindered the examination of this potentially important class of virulence genes. we have developed a technique to identify chlamydia proteins that can be translocated into the host cell cytoplasm by a type i ...	2005	15664932
murein lipoprotein is a critical outer membrane component involved in salmonella enterica serovar typhimurium systemic infection.	lipopolysaccharide (lps) and braun (murein) lipoprotein (lpp) are major components of the outer membrane of gram-negative enteric bacteria that function as potent stimulators of inflammatory and immune responses. in a previous paper, we provided evidence that two functional copies of the lipoprotein gene (lppa and lppb) located on the chromosome of salmonella enterica serovar typhimurium contributed to bacterial virulence. in this study, we characterized lppa and lppb single-knockout (sko) mutan ...	2005	15664952
salmonella-induced filament formation is a dynamic phenotype induced by rapidly replicating salmonella enterica serovar typhimurium in epithelial cells.	salmonella enterica serovar typhimurium has the fascinating ability to form tubular structures known as salmonella-induced filaments (sifs) in host cells. here, we show that the prevalence of the sif phenotype in hela cells is affected by host cell density, growth, and the multiplicity of infection. sif formation was observed in cells that displayed rapid intracellular bacterial replication and was found to be dynamic, being maximal 8 to 10 h postinfection and declining thereafter. the virulence ...	2005	15664965
use of molecular hydrogen as an energy substrate by human pathogenic bacteria.	molecular hydrogen is produced as a fermentation by-product in the large intestine of animals and its production can be correlated with the digestibility of the carbohydrates consumed. pathogenic helicobacter species (helicobacter pylori and h. hepaticus) have the ability to use h(2) through a respiratory hydrogenase, and it was demonstrated that the gas is present in the tissues colonized by these pathogens (the stomach and the liver respectively of live animals). mutant strains of h. pylori un ...	2005	15667272
detoxification of nitric oxide by the flavorubredoxin of salmonella enterica serovar typhimurium.	salmonella possesses multiple enzymes that utilize no as a substrate, and could therefore contribute to the organism's ability to resist nitrosative killing by macrophages. flavorubredoxin is an oxygen-sensitive enzyme that reduces no to nitrous oxide. the salmonella enterica serovar typhimurium norv gene encoding flavorubredoxin was disrupted and the no sensitivity of the mutant was determined. the norv mutant showed a greater sensitivity to no than wild-type s. typhimurium, but did recover gro ...	2005	15667306
multidrug-resistant salmonella enterica serovar muenchen from pigs and humans and potential interserovar transfer of antimicrobial resistance.	salmonella serovars are important reservoirs of antimicrobial resistance. recently, we reported on multidrug-resistant (mdr) salmonella enterica serovar typhimurium strains among pigs with resistance to ampicillin, kanamycin, streptomycin, sulfamethoxazole, and tetracycline (resistance [r] type akssut) and resistance to amoxicillin-clavulanic acid, ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (r type axacssut). in the present study, 67 isolates (39 from humans an ...	2005	15673725
dissemination of sulfonamide resistance genes (sul1, sul2, and sul3) in portuguese salmonella enterica strains and relation with integrons.	in 200 sulfonamide-resistant portuguese salmonella isolates, 152 sul1, 74 sul2, and 14 sul3 genes were detected. class 1 integrons were always associated with sul genes, including sul3 alone in some isolates. the sul3 gene has been identified in isolates from different sources and serotypes, which also carried a class 1 integron with aada and dfra gene cassettes.	2005	15673783
selected arylpiperazines are capable of reversing multidrug resistance in escherichia coli overexpressing rnd efflux pumps.	several arylpiperazines capable of reversing multidrug resistance (mdr) in escherichia coli overexpressing acrab and acref but not in pump-deficient mutant strains were identified. 1-(1-naphthylmethyl)-piperazine, one of the more active compounds, enhanced susceptibility to fluoroquinolones and other agents and increased the intracellular concentration of levofloxacin and ethidium bromide, suggesting efflux pump inhibition as the mechanism of mdr reversal.	2005	15673787
high-level resistance to fluoroquinolones linked to mutations in gyra, parc, and pare in salmonella enterica serovar schwarzengrund isolates from humans in taiwan.		2005	15673791
first extended-spectrum-beta-lactamase (ctx-m-15)-producing salmonella enterica serotype typhimurium isolate identified in lebanon.		2005	15673792
antimicrobial activity of five essential oils against origin strains of the enterobacteriaceae family.	an in vitro assay measuring the antimicrobial activity of essential oils of coridothymus capitatus (spanish origanum), satureja montana, thymus mastichina (spanish origanum majorana), thymus zygis (spanish variety of thymus vulgaris) and origanum vulgare has been carried out against poultry origin strains of escherichia coli, salmonella enteritidis and salmonella essen, and pig origin strains of enterotoxigenic e. coli (etec), salmonella choleraesuis and salmonella typhimurium. using the broth m ...	2005	15676008
identification and functional analysis of salmonella enterica serovar typhimurium pmra-regulated genes.	the pmra-pmrb two-component regulatory system of salmonella enterica serovar typhimurium is activated in vivo and plays an important role in resistance to cationic antimicrobial peptides. resistance is partly mediated by modifications to the lipopolysaccharide. to identify new pmra-regulated genes, microarray analysis was undertaken comparing cdna derived from pmra-constitutive and pmra-null strains. a combination of rt-pcr and transcriptional analysis confirmed the inclusion of six new loci in ...	2005	15681155
inhibition of ifn-gamma-stimulated proinflammatory cytokines by vasoactive intestinal peptide (vip) correlates with increased survival of salmonella enterica serovar typhimurium phop in murine macrophages.	vasoactive intestinal peptide (vip)is a novel th2 cytokine that has been shown previously to rescue rats and mice from the lethal effect of bacterial lipopolysaccharide (lps). we report that vip inhibited production of the proinflammatory cytokines, tumor necrosis factor-alpha(tnf-alpha)and interleukin-1beta (il-1beta), at the mrna level and that the inhibitory effect of vip was maintained when macrophages were cocultured with an immunostimulatory concentration of interferon-gamma (ifn-gamma)(10 ...	2005	15684620
the flag-2 locus, an ancestral gene cluster, is potentially associated with a novel flagellar system from escherichia coli.	escherichia coli k-12 possesses two adjacent, divergent, promoterless flagellar genes, fhia-mbha, that are absent from salmonella enterica. through bioinformatics analysis, we found that these genes are remnants of an ancestral 44-gene cluster and are capable of encoding a novel flagellar system, flag-2. in enteroaggregative e. coli strain 042, there is a frameshift in lfgc that is likely to have inactivated the system in this strain. tiling path pcr studies showed that the flag-2 cluster is pre ...	2005	15687208
host gene expression changes and dna amplification during temperate phage induction.	salmonella enterica serovar typhimurium lt2 harbors four temperate prophages. the lytic cycle of these phages was induced with hydrogen peroxide or mitomycin c. microarray analysis was used to monitor the increase in phage genome copy number and the changes in rna expression. phage gene transcription was classified temporally, and host genes that responded to hydrogen peroxide, mitomycin c, or phage induction were also identified. a region of the serovar typhimurium lt2 host genome encompassing ...	2005	15687213
[virulence plasmids of salmonella enterica--incidence and properties].	salmonella virulence plasmids (svps) are large and closely related low-copy plasmids harbored by certain serovars of salmonella enterica subspecies enterica. these serovars not only comprise those of veterinary significance like abortusequi, abortusovis, choleraesuis, dublin and gallinarum/pullorum, but also typhimurium and enteritidis which currently are the most prevalent serotypes in humans and food animals. experiments with several animal species gave evidence that svps increase salmonella s ...	2005	15690632
inhibition of listeria monocytogenes and salmonella by natural antimicrobials and high hydrostatic pressure in sliced cooked ham.	the effectiveness of nisin, lactate salts, and high hydrostatic pressure to inhibit the growth of listeria monocytogenes and salmonella in sliced cooked ham was studied through a combination of pcr-based detection methods, most probable number, and classical microbial enumeration techniques (international organization for standardization protocols). a synergistic effect to inhibit a cocktail of listeria monocytogenes ctc1010, ctc1011, and ctc1034 was observed between potassium lactate, high hydr ...	2005	15690822
culture methods differ on the isolation of salmonella enterica serotypes from naturally contaminated swine fecal samples.	four culture methods (a, b, c, and d) were comparatively evaluated for their ability to isolate salmonella enterica from pooled swine fecal samples (n = 100). none of the methods was able to isolate salmonella from all positive samples. the relative sensitivity of the culture methods evaluated was 82%, 94%, 95%, and 78% for methods a, b, c, and d, respectively. the comparison of sensitivities showed that methods b and c performed significantly better (p < 0.05) than methods a and d. although rel ...	2005	15690959
disposition of orally administered cefpodoxime proxetil in foals and adult horses and minimum inhibitory concentration of the drug against common bacterial pathogens of horses.	to determine the disposition of orally administered cefpodoxime proxetil in foals and adult horses and measure the minimum inhibitory concentrations (mics) of the drug against common bacterial pathogens of horses.	2005	15691032
a novel mechanism for connecting bacterial two-component signal-transduction systems.	bacteria have many two-component signal-transduction systems (tcss) that respond to specific environmental signals by altering the phosphorylated state of a response regulator. although these systems are presumed to form an intricate signal network, the detailed mechanism of how they interact with each other remains largely unexplained. in a recent study of salmonella, two tcss have been discovered to be connected by a protein that protects a response regulator from dephosphorylation promoted by ...	2005	15691651
antimicrobial action of carvacrol at different stages of dual-species biofilm development by staphylococcus aureus and salmonella enterica serovar typhimurium.	the effects of carvacrol, a natural biocide, on dual-species biofilms formed by staphylococcus aureus and salmonella enterica serovar typhimurium were investigated with a constant-depth film fermentor. biofilm development reached a quasi-steady state in 12 days at 25 degrees c with s. aureus predominance ( approximately 99%). cryosectional analysis detected viable s. aureus and s. enterica serovar typhimurium at depths of 320 and 180 mum from the film surface, respectively. carvacrol pulses (1.0 ...	2005	15691933
prevalence of salmonella spp. in oysters in the united states.	food-borne diseases such as salmonellosis can be attributed, in part, to the consumption of raw oysters. to determine the prevalence of salmonella spp. in oysters, oysters harvested from 36 u.s. bays (12 each from the west, east, and gulf coasts in the summer of 2002, and 12 bays, four per coast, in the winter of 2002-2003) were tested. salmonella was isolated from oysters from each coast of the united states, and 7.4% of all oysters tested contained salmonella. isolation tended to be bay specif ...	2005	15691945
manipulation of the host actin cytoskeleton by salmonella--all in the name of entry.	the invasive pathogen salmonella enterica has evolved sophisticated mechanisms to subvert the cytoskeletal machinery of its host. following contact with the host cell, it delivers a distinct arsenal of effector proteins directly into the cytoplasm. these bacterial effectors coordinate transient actin rearrangements and alter vesicle trafficking to trigger invasion, without causing overt cellular damage. recent studies have shed new light on the signaling mechanisms underlying this remarkable hos ...	2005	15694851
bacterial interactions with the eukaryotic secretory pathway.	pathogenic bacteria exploit a wide variety of host cellular processes to adhere to, invade, replicate within and damage host cells. one such process is the eukaryotic secretory pathway, in which proteins and lipids are modified and transported from the endoplasmic reticulum through the golgi network to the plasma membrane and other cellular destinations. certain bacteria secrete toxins that utilise this transport pathway to reach their cellular targets. some intracellular pathogens, including le ...	2005	15694862
high rate of fatal cases of pediatric septicemia caused by gram-negative bacteria with extended-spectrum beta-lactamases in dar es salaam, tanzania.	extended-spectrum beta-lactamases (esbls) were present in high proportions of escherichia coli (25% [9 of 36]) and klebsiella pneumoniae isolates (17% [9 of 52]) causing pediatric septicemia at a tertiary hospital in tanzania. patients with septicemia due to esbl-producing organisms had a significantly higher fatality rate than those with non-esbl isolates (71% versus 39%, p = 0.039). this is the first report of the ctx-m-15 genotype of esbls on the african continent and the first observation of ...	2005	15695674
nalidixic acid-resistant salmonella enterica serotype typhi presenting as a primary psoas abscess: case report and review of the literature.	we report an unusual case of salmonella enterica serotype typhi presenting as a primary psoas abscess. the isolate tested susceptible to ciprofloxacin but resistant to nalidixic acid in vitro, a pattern associated with fluoroquinolone therapeutic failures. we review the literature for serovar typhi psoas abscess in the absence of bacteremia and discuss the importance of identifying isolates with reduced susceptibility to fluoroquinolones.	2005	15695728
ifn-gamma priming of chicken heterophils upregulates the expression of proinflammatory and th1 cytokine mrna following receptor-mediated phagocytosis of salmonella enterica serovar enteritidis.	responsiveness to invasive pathogens, clearance via the inflammatory response, and activation of appropriate acquired responses are all coordinated by innate host defenses. polymorphonuclear leukocytes (pmns) are cellular components of innate response, with the primary pmn in poultry being the heterophil. priming is the potentiation of the phagocyte activation process. interferon-gamma (ifn-gamma) is a pleiotropic cytokine involved in basically all phases of immune and inflammatory responses tha ...	2005	15695928
purified beta-glucan as an abiotic feed additive up-regulates the innate immune response in immature chickens against salmonella enterica serovar enteritidis.	functionally, the innate immune system of immature chickens is inefficient during the first week posthatch. this immunological inefficiency enables pathogens such as salmonella enterica serovar enteritidis (se) to invade and colonize the visceral organs of immature chickens. the objective of this study was to evaluate the effect of purified beta-glucan as an immunomodulator of the innate immune response. beta-glucan, as a feed additive, significantly provided protection against se organ invasion ...	2005	15698692