| laboratory-based surveillance of nontyphoidal salmonella infections in china. | abstract foodborne infections are an important public health problem in china. in 2008, we conducted surveillance for laboratory-confirmed nontyphoidal salmonella to monitor trends for this infection in china and to build capacity for rapid detection and response to foodborne outbreaks. salmonella isolates from patients with diarrhea were sent from hospitals to local public health laboratories for confirmation, serotyping, and antimicrobial susceptibility testing. a total of 126 hospitals in 44 ... | 2011 | 21492026 |
| differences in salmonella enterica serovar typhimurium strain invasiveness is associated with heterogeneity in spi-1 gene expression. | most studies on salmonella enterica serovar typhimurium infection focus on strains sl1344 or 12023 (atcc 14028). we have compared the abilities of these strains to induce membrane ruffles and invade epithelial cells. s. typhimurium strain 12023 is less invasive and induces smaller membrane ruffles on mdck cells compared with sl1344. since the spi-1 effector sope is present in sl1344 and absent from 12023, and sl1344 sope mutants have reduced invasiveness, we investigated whether 12023 is less in ... | 2011 | 21493681 |
| ultra-fast and sensitive detection of non-typhoidal salmonella using microwave-accelerated metal-enhanced fluorescence ("mamef"). | certain serovars of salmonella enterica subsp. enterica cause invasive disease (e.g., enteric fever, bacteremia, septicemia, meningitis, etc.) in humans and constitute a global public health problem. a rapid, sensitive diagnostic test is needed to allow prompt initiation of therapy in individual patients and for measuring disease burden at the population level. an innovative and promising new rapid diagnostic technique is microwave-accelerated metal-enhanced fluorescence (mamef). we have adapted ... | 2011 | 21494634 |
| thermal resistance of salmonella enterica serovar anatum on cabbage surfaces during drying: effects of drying methods and conditions. | the effects of selected drying methods, i.e., hot air drying, vacuum drying and low-pressure superheated steam drying (lpssd), on the heat resistance of salmonella attached on vegetable surface, which are data that have never been reported elsewhere, were investigated at drying temperatures of 50-70°c; vacuum drying and lpssd were carried out at an absolute pressure of 10kpa. the selected salmonella serovar, i.e., s. anatum, was used as a test organism. cabbage was used as a vegetable model to r ... | 2011 | 21496933 |
| killing of candida albicans filaments by salmonella enterica serovar typhimurium is mediated by sopb effectors, parts of a type iii secretion system. | although bacterial-fungal interactions shape microbial virulence during polymicrobial infections, only a limited number of studies have evaluated this interaction on a genetic level. we report here that one interaction is mediated by sopb, an effector of a type iii secretion system (ttss) of salmonella enterica serovar typhimurium. in these studies, we screened 10 ttss effector-related mutants and determined their role in the killing of c. albicans filaments in vitro during coinfection in plankt ... | 2011 | 21498643 |
| antibacterial activity in spices and local medicinal plants against clinical isolates of karachi, pakistan. | context: development of resistance in human pathogens against conventional antibiotic necessitates searching indigenous medicinal plants having antibacterial property. twenty-seven medicinal plants used actively in folklore, ayurvedic and traditional system of medicine were selected for the evaluation of their antimicrobial activity for this study. eleven plants chosen from these 27 are used as spices in local cuisine. objective: evaluation of the effectiveness of some medicinal plant extracts a ... | 2011 | 21501041 |
| equivalence of quality control strains of microorganisms used in the compendial microbiological tests: are national culture collection strains identical? | the pharmacopoeias list a number of microorganisms to be used in the compendial microbiological tests for confirming the growth-promoting, indicative, and inhibitory properties of the media and demonstrating the suitability of the test for a specific test article. major national culture collections are specified as the sources for these test strains based on their history of deposition and maintenance and use in the compendial tests. using these microorganisms, it has long been assumed that thes ... | 2010 | 21502014 |
| acra dependency of the acrd efflux pump in salmonella enterica serovar typhimurium. | multidrug efflux pumps belonging to the resistance-nodulation cell division (rnd) family have major roles in the intrinsic and elevated resistance of gram-negative bacteria to a wide range of compounds. rnd efflux pumps require two other proteins to function: a membrane fusion protein (mfp) and an outer membrane protein. a recent study demonstrated that salmonella enterica serovar typhimurium has five rnd efflux systems: acrab, acrd, acref, mdtabc and mdsabc. most rnd efflux system genes also co ... | 2011 | 21505470 |
| comparative analysis of the bacterial flora of vegetables collected directly from farms and from supermarkets in germany. | a total of 1,001 vegetables were collected from 13 farms and 11 supermarkets in bavaria, germany; 722 samples were positive for coliforms (mostly enterobacter cloacae; n = 176). escherichia coli were detected in 34, pseudomonas spp. in 439, salmonella spp. in 1, enterococcus spp. in 682, and listeria spp. in 11 samples. prevalence of all investigated genera tended to be lower in samples collected at the supermarket. however, prevalence of pseudomonas fluorescens was higher in supermarket samples ... | 2011 | 21506036 |
| activation of cryptic aminoglycoside resistance in salmonella enterica. | aminoglycoside resistance in bacteria can be acquired by several mechanisms, including drug modification, target alteration, reduced uptake and increased efflux. here we demonstrate that increased resistance to the aminoglycosides streptomycin and spectinomycin in salmonella enterica can be conferred by increased expression of an aminoglycoside adenyl transferase encoded by the cryptic, chromosomally located aada gene. during growth in rich medium the wild-type strain was susceptible but mutatio ... | 2011 | 21507083 |
| biofilm formation by salmonella enterica serovar typhimurium colonizing solid tumours. | systemic administration of salmonella enterica serovar typhimurium to tumour bearing mice results in preferential colonization of the tumours and retardation of tumour growth. although the bacteria are able to invade the tumour cells in vitro, in tumours they were never detected intracellularly. ultrastructural analysis of salmonella-colonized tumours revealed that the bacteria had formed biofilms. interestingly, depletion of neutrophilic granulocytes drastically reduced biofilm formation. obvio ... | 2011 | 21507181 |
| national outbreak of salmonella enteritidis phage type 14b in england, september to december 2009: case-control study. | we conducted an unmatched retrospective case–control study to investigate an upsurge of non-travel-related sporadic cases of infection with salmonella enterica subsp. enterica serotype enteritidis phage type 14b with antimicrobial resistance to nalidixic acid and partial resistance to ciprofloxacin (s. enteritidis pt 14b nxcp(l)) that was reported in england from 1 september to 31 december 2009. we analysed data from 63 cases and 108 controls to determine whether cases had the same sources of in ... | 2011 | 21507321 |
| structural basis for microcin c7 inactivation by the mcce acetyltransferase. | the antibiotic microcin c7 (mcc) acts as a bacteriocide by inhibiting aspartyl trna synthetase, and stalling the protein translation machinery. mcc is synthesized as a heptapeptide-nucleotide conjugate, which is processed by cellular peptidases within target strains to yield the biologically active compound. as unwanted processing of intact mcc can result in self-toxicity, producing strains utilize multiple mechanisms for autoimmunity against processed mcc. we have previously shown that the mcce ... | 2011 | 21507941 |
| effect of the growth environment on the strain variability of salmonella enterica kinetic behavior. | intra-species variability of microbial growth kinetic behavior is an event with important implications for food safety research. aiming at the evaluation of the growth variability among salmonella enterica strains as affected by the growth environment, the kinetic behavior of 60 isolates of the pathogen was assessed at 37 °c in tryptone soy broth of different ph values (4.3-7.0) and nacl concentrations (0.5-6.0%). maximum specific growth rate (μ(max)) values corresponding to each strain and grow ... | 2011 | 21511146 |
| purification, amino acid sequence and characterization of the class iia bacteriocin weissellin a, produced by weissella paramesenteroides dx. | weissella paramesenteroides dx has been shown to produce a 4450-da class iia bacteriocin, weissellin a, composed of 43 amino acids with the sequence knygngvycnkhkcsvdwatfsaniannsvamagltggnagn. the bacteriocin shares 68% similarity with leucocin c from leuconostoc mesenteroides. computational analyses predict that the bacteriocin is a hydrophobic molecule with a beta-sheet type conformation. weissellin a exhibited various levels of activity against all gram-positive bacteria tested, but was not a ... | 2011 | 21511463 |
| contribution of the phop/q regulon to survival and replication of salmonella enterica serovar typhimurium in macrophages. | the ability of serovars of salmonella enterica to cause systemic disease is dependent upon their survival and replication within macrophages. to do this, bacteria must withstand or surmount bacteriostatic and bactericidal responses by the host cell, including the delivery of hydrolytic enzymes from lysosomes to the phagosome. the bacterial two component regulatory system, phop/q, has been implicated in avoidance of phagolysosomal fusion by s. enterica serovar typhimurium in murine macrophages. i ... | 2011 | 21511762 |
| rapid screening of epidemiologically important salmonella enterica subsp. enterica serovars using whole-cell maldi-tof mass spectrometry. | currently, 2,610 different salmonella serovars are described according to the white-kauffmann-le minor scheme. they are routinely differentiated by serotyping, which is based on the antigenic variability at lipopolysaccharide moieties (o antigens), flagellar proteins (h1 and h2 antigens), and capsular polysaccharides (vi antigens). the aim of this study was to evaluate the potential of maldi-tof mass spectrometry for rapid screening and identification of epidemiologically important salmonella en ... | 2011 | 21515723 |
| low expression of acrb in the deoxycholate-sensitive strains of salmonella enterica subspecies enterica serovar pullorum. | we investigated the mechanism responsible for bile susceptibility in three deoxycholate-sensitive (dcs) strains of salmonella enterica subspecies enterica serovar pullorum isolated in 1958 in japan. of the genes encoding the acrab-tolc efflux system, the expression of acrb mrna was 10-fold lower in the dcs strains than in a deoxycholate-resistant (dcr) strain, whereas those of the acra and tolc genes were two-fold lower. these results suggested that low expression of acrb was strongly correlated ... | 2011 | 21517946 |
| integration of a complex regulatory cascade involving the sira/bara and csr global regulatory systems that controls expression of the salmonella spi-1 and spi-2 virulence regulons through hild. | salmonella pathogenicity islands 1 and 2 (spi-1 and spi-2) play key roles in the pathogenesis of salmonella enterica. previously, we showed that when salmonella grows in luria-bertani medium, hild, encoded in spi-1, first induces the expression of hila, located in spi-1, and subsequently of the ssrab operon, located in spi-2. these genes code for hila and the ssra/b two-component system, the positive regulators of the spi-1 and spi-2 regulons respectively. in this study, we demonstrate that csra ... | 2011 | 21518393 |
| outbreak of salmonella braenderup infection originating in boxed lunches in japan in 2008. | there have been only 2 reports of a large-scale foodborne outbreak arising from salmonella enterica serotype braenderup infection worldwide. on august 9, 2008, an outbreak originating in boxed lunches occurred in okayama, japan. we conducted a cohort study of 786 people who received boxed lunches from a particular catering company and collected 644 questionnaires (response rate:82%). cases were defined as those presenting with diarrhea (≧4 times in 24h) or fever (≧38℃) between 12 am on august 8 ... | 2011 | 21519363 |
| antibacterial activity of different honeys against pathogenic bacteria. | to study the antimicrobial activity of honey, 60 samples of various botanical origin were evaluated for their antimicrobial activities against 16 clinical pathogens and their respective reference strains. the microbiological quality of honeys and the antibiotic susceptibility of the various isolates were also examined. the bioassay applied for determining the antimicrobial effect employs the well-agar diffusion method and the estimation of minimum active dilution which produces a 1mm diameter in ... | 2011 | 21524711 |
| presence and distribution of fungi and bacteria in the reproductive tract of healthy stallions. | a saprophytic bacterial flora is present on the penis and the distal part of the urethra of stallions. little is known about the fungal flora of their reproductive tract. as micro organisms play an important role in mares fertility, the aim of the study was to describe the distribution of fungi and bacteria in the normal genital apparatus of stallions. the microbic flora of the reproductive tract of 11 healthy, fertile stallions was evaluated, collecting samples from 5 different locations: ureth ... | 2011 | 21529914 |
| the x-ray structure of the zinc transporter znua from salmonella enterica discloses a unique triad of zinc-coordinating histidines. | znua is the soluble component of the high-affinity znuabc zinc transporter belonging to the cluster 9 group of atp-binding cassette-type periplasmic zn- and mn-binding proteins. in gram-negative bacteria, the znuabc system is essential for zinc uptake and homeostasis and is an important determinant of bacterial resistance to the host defense mechanisms. the cluster 9 members share a two (α/β)(4) domain architecture with a long α-helix connecting the two domains. in the zn-specific proteins, the ... | 2011 | 21530543 |
| a discriminant based charge deconvolution analysis pipeline for protein profiling of whole cell extracts using liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry. | a discriminant based charge deconvolution analysis pipeline is proposed. the molecular weight determination (mowed) charge deconvolution method was applied directly to the discrimination rules obtained by the fuzzy rule-building expert system (fures) pattern classifier. this approach was demonstrated with synthetic electrospray ionization-mass spectra. identification of the tentative protein biomarkers by bacterial cell extracts of salmonella enterica serovar typhimurium strains a1 and a19 by li ... | 2011 | 21530796 |
| gatifloxacin versus chloramphenicol for uncomplicated enteric fever: an open-label, randomised, controlled trial. | we aimed to investigate whether gatifloxacin, a new generation and affordable fluoroquinolone, is better than chloramphenicol for the treatment of uncomplicated enteric fever in children and adults. | 2011 | 21531174 |
| expression and activity of a novel cathelicidin from domestic cats. | cathelicidins are small cationic antimicrobial peptides found in many species including primates, mammals, marsupials, birds and even more primitive vertebrates, such as the hagfish. some animals encode multiple cathelicidins in their genome, whereas others have only one. this report identifies and characterizes feline cathelicidin (fecath) as the sole cathelicidin in domestic cats (felis catus). expression of fecath is predominantly found in the bone marrow, with lower levels of expression in t ... | 2011 | 21533281 |
| minimal effects of high-pressure treatment on salmonella enterica serovar typhimurium inoculated into peanut butter and peanut products. | about 1.2 billion pounds of peanut butter are consumed annually in the united states. in 2008 to 2009, an outbreak involving salmonella typhimurium in peanut butter led to a recall of over 3900 products by over 200 companies. more than 700 people became sick, 100 were hospitalized, and 9 people died from this outbreak. this study examines the efficacy of high-pressure processing (hpp) to decrease s. typhimurium american type culture collection (atcc) 53647 inoculated into peanut butter and model ... | 2010 | 21535491 |
| evaluation of antibacterial activity of 3-butenyl, 4-pentenyl, 2-phenylethyl, and benzyl isothiocyanate in brassica vegetables. | this study investigated antibacterial activities of 4 isothiocyanates (3-butenyl, 4-phentenyl, 2-phenylethyl, and benzyl isothiocyanate) against 4 gram-positive bacteria (bacillus cereus, bacillus subtilis, listeria monocytogenes, and staphylococcus aureus) and 7 gram-negative bacteria (aeromonas hydrophila, pseudomonas aeruginosa, salmonella choleaesuis, salmonella enterica, serratia marcescens, shigella sonnei, and vibrio parahaemolyticus) by an agar disc diffusion assay. benzyl isothiocyanate ... | 2010 | 21535549 |
| recovery of salmonella enterica serovars typhimurium and tennessee in peanut butter after electron beam exposure. | the effect of electron beam (e-beam) radiation on the recovery of salmonella serotypes tennessee (atcc 10722) and typhimurium (atcc 14028) in creamy peanut butter over a 14-d storage period at 22 °c was studied. each salmonella type was independently inoculated into peanut butter and subjected to e-beam doses that ranged from 0 to 3.1 kgy, confirmed by film dosimetry. after 2-, 4-, 6-, 8-, and 14-d of storage, microbial analyses were conducted. survivors were recovered on growth and selective me ... | 2010 | 21535557 |
| inappropriate use of d-values for determining biocidal activity of various antimicrobials. | the objective of this study was to investigate the application of established d-value calculations to survival curves for various bacteria using the following antimicrobials: acidified sodium chlorite, triclosan, octanoic acid, and sodium hydroxide. d-values can be calculated in 3 ways, a linear regression, an endpoint calculation, or an average of multiple endpoint calculations. the assumption made in calculating a d-value is that the rate of kill follows 1st-order kinetics under specified trea ... | 2011 | 21535698 |
| physical and antibacterial properties of edible films formulated with apple skin polyphenols. | fruit and vegetable skins have polyphenolic compounds, terpenes, and phenols with antimicrobial and antioxidant activity. these flavoring plant essential oil components are generally regarded as safe. edible films made from fruits or vegetables containing apple skin polyphenols have the potential to be used commercially to protect food against contamination by pathogenic bacteria. the main objective of this study was to evaluate physical properties as well as antimicrobial activities against lis ... | 2011 | 21535779 |
| modification of buffered peptone water for improved recovery of heat-injured salmonella typhimurium. | rapid detection of salmonella in foods is often limited by the high demand for the sensitivity of detection, poor physiological conditions of the target cells, and high concentration of background flora. in this study, the conditions of nonselective enrichment cultivation were modified in order to improve the quantitative detection of heat-injured salmonella in minced meat. the effect of the modifications on the recovery was observed by means of rna-based sandwich hybridization, which was adjust ... | 2011 | 21535838 |
| application of polylactic acid coating with antimicrobials in reduction of escherichia coli o157:h7 and salmonella stanley on apples. | survival of escherichia coli o157:h7 and salmonella stanley on apples as affected by application of polylactic acid (pla) coating with antimicrobials was investigated. golden delicious apples were spot inoculated with e. coli o157:h7 or s. stanley and spray coated with pla solutions containing lactic acid (la), disodium ethylenediaminetetraacetic acid (edta), sodium benzoate (sb), potassium sorbate (ps), or their combination (la + edta, sb + la, sb + la + edta). apples without any coating treatm ... | 2011 | 21535842 |
| chronic typhoid infection and the risk of biliary tract cancer and stones in shanghai, china. | abstract: previous studies have shown a positive association between chronic typhoid carriage and biliary cancers. we compared serum salmonella enterica serovar typhi antibody titers between biliary tract cancer cases, biliary stone cases without evidence of cancer, and healthy subjects in a large population-based case-control study in shanghai, china.participants included 627 newly diagnosed primary biliary tract cancer patients; 1,037 biliary stone cases (774 gallbladder and 263 bile-duct) and ... | 2011 | 21535882 |
| the antibiotic dehydrophos is converted to a toxic pyruvate analog by peptide bond cleavage in salmonella enterica. | the metabolic processing of dehydrophos, a broad-spectrum peptide antibiotic containing an unusual vinyl-phosphonate moiety, was examined using a panel of salmonella enterica mutants deficient in peptide uptake and catabolism. dehydrophos bioactivity is lost in opp, tpp double mutants, demonstrating a requirement for uptake via non-specific oligopeptide permeases. dehydrophos bioactivity is also abolished in a quadruple salmonella mutant lacking the genes encoding peptidases a, b, d, and n, show ... | 2011 | 21537024 |
| [experiences in the epidemiological surveillance of foodborne pathogens by pulsed field gel electrophoresis (pfge) in peru.] | foodborne diseases and other enteric infections often occur as outbreaks and cause morbidity and mortality all over the world. in perú, they represent a serious public health problem, and are caused by a great variety of infectious agents. for epidemiological research, a wide array of typification methods are used. one of the most important tools for the molecular subtyping of bacterial pathogens is the pulsed field gel electrophoresis (pfge), which is a highly precise method that allows the dis ... | 2011 | 21537781 |
| a comprehensive study of the contribution of salmonella enterica serovar typhimurium spi2 effectors to bacterial colonization, survival, and replication in typhoid fever, macrophage, and epithelial cell infection models. | salmonella enterica serovars are gram-negative bacterial pathogens responsible for human diseases including gastroenteritis and typhoid fever. after ingestion, salmonella cross the intestinal epithelial barrier, where they are phagocytosed by macrophages and dendritic cells, which then enables their spread to systemic sites during cases of typhoid fever. salmonella use two type 3 secretion systems encoded by salmonella pathogenicity islands (spi) 1 and 2 to inject virulence proteins into host ce ... | 2011 | 21540636 |
| active suppression of early immune response in tobacco by the human pathogen salmonella typhimurium. | the persistence of enteric pathogens on plants has been studied extensively, mainly due to the potential hazard of human pathogens such as salmonella enterica being able to invade and survive in/on plants. factors involved in the interactions between enteric bacteria and plants have been identified and consequently it was hypothesized that plants may be vectors or alternative hosts for enteric pathogens. to survive, endophytic bacteria have to escape the plant immune systems, which function at d ... | 2011 | 21541320 |
| systemic and mucosal immunity induced by attenuated salmonella enterica serovar typhimurium expressing orf7 of porcine reproductive and respiratory syndrome virus. | oral administration of attenuated salmonella vaccine may provide valuable advantages such as low cost, easy preparation, and safety. attenuated salmonella vaccines also serve as carriers of foreign antigens and immunomodulatory cytokines. presently, an attenuated salmonella enterica serovar typhimurium strain was used as a carrier for open reading frame 7 (orf7) protein of porcine reproductive and respiratory syndrome virus (prrsv), a swine pathogen of significant global economic importance. ini ... | 2011 | 21543119 |
| masscode liquid arrays as a tool for multiplexed high-throughput genetic profiling. | multiplexed detection assays that analyze a modest number of nucleic acid targets over large sample sets are emerging as the preferred testing approach in such applications as routine pathogen typing, outbreak monitoring, and diagnostics. however, very few dna testing platforms have proven to offer a solution for mid-plexed analysis that is high-throughput, sensitive, and with a low cost per test. in this work, an enhanced genotyping method based on masscode technology was devised and integrated ... | 2011 | 21544191 |
| efficacy of ε-polylysine, lauric arginate, or acidic calcium sulfate applied sequentially for salmonella reduction on membrane filters and chicken carcasses. | salmonella contamination continues to be one of the major concerns for the microbiological safety of raw poultry products. application of more than one decontamination agent as a multihurdle intervention to carcasses in a processing line might produce greater reductions than one treatment alone due to different modes of action of individual antimicrobials. in this study, all possible two-way combinations and individual applications of ε-polylysine (epl), lauric arginate (lae), and acidic calcium ... | 2011 | 21549044 |
| prevalence of salmonella enterica, listeria monocytogenes, and escherichia coli virulence factors in bulk tank milk and in-line filters from u.s. dairies. | the zoonotic bacteria salmonella enterica, listeria monocytogenes, and escherichia coli are known to infect dairy cows while not always causing clinical signs of disease. these pathogens are sometimes found in raw milk, and human disease outbreaks due to these organisms have been associated with the consumption of raw milk or raw milk products. bulk tank milk (btm) samples (536) and in-line milk filters (519) collected from dairy farms across the united states during the national animal health m ... | 2011 | 21549046 |
| crystal structures of slya, a master virulence regulator of salmonella, in free and dna-bound states. | slya is a master virulence regulator that controls the transcription of numerous genes in salmonella enterica. we present here crystal structures of slya by itself and bound to a high-affinity dna operator sequence in the slya gene. slya interacts with dna through direct recognition of a guanine base by r65, as well as interactions between conserved r86 and the minor groove and a large network of non-base-specific contacts to the sugar-phosphate backbone. our structures, together with an unpubli ... | 2011 | 21550983 |
| n-benzyl-3-sulfonamidopyrrolidines are a new class of bacterial dna gyrase inhibitors. | this paper characterizes n-benzyl-3-sulfonamidopyrrolidines (gyramides) as dna gyrase inhibitors. gyramide a was previously shown to exhibit antimicrobial activity that suggested it inhibited bacterial cell division. in this study, we conducted target identification studies and identified dna gyrase as the primary target of gyramide a. the gyramide a resistance-determining region in dna gyrase is adjacent to the dna cleavage gate and is a new site for inhibitor design. we studied the antibiotic ... | 2011 | 21552338 |
| secondary renal tubular acidosis in a hereford calf. | a 3-month-old hereford heifer calf was presented for lethargy. blood gas analysis and plasma biochemical testing revealed severe metabolic acidosis, azotemia, hyponatremia, hyperchloremia, and normal anion gap. results of a urinalysis were consistent with acute tubular necrosis with inadequate acidification of urine based on the degree of acidemia. salmonella enterica serovar agona was cultured from both urine and feces. the calf was treated with intravenous polyionic fluids, bicarbonate, and an ... | 2011 | 21554363 |
| yqic of salmonella enterica serovar typhimurium is a membrane fusogenic protein required for mice colonization. | abstract: | 2011 | 21554724 |
| immune response of chicken gut to natural colonisation by gut microflora and to salmonella enterica serovar enteritidis infection. | in commercial poultry production, there is a lack of natural flora providers since chickens are hatched in the clean environment of a hatchery. events occurring soon after hatching are therefore of particular importance and that is why we were interested in the development of the gut microbial community, the immune response to natural microbial colonisation and the response to salmonella enteritidis infection as a function of chicken age. the complexity of chicken gut microbiota gradually increa ... | 2011 | 21555397 |
| protective role of akt2 in salmonella enterica serovar typhimurium-induced gastroenterocolitis. | the salmonella effector protein sopb has previously been shown to induce activation of akt and protect epithelial cells from apoptosis in vitro. to characterize the role of akt2 in host defense against salmonella typhimurium infection, wild-type (wt) mice and mice lacking akt2 (akt2 ko) were infected using a salmonella acute gastroenteritis model. infected akt2 ko mice showed a more pronounced morbidity and mortality associated with higher bacterial loads in the intestines, and elevated levels o ... | 2011 | 21555401 |
| adhesive mechanisms of salmonella enterica. | salmonella enterica is an invasive, facultative intracellular pathogen of animal and man with the ability to colonize various niches in diverse host organisms. the pathogenesis of infections by s. enterica requires adhesion to various host cell surfaces, and a large number of adhesive structures can be found. depending on the serotype of s. enterica, gene clusters for more than 10 different fimbrial adhesins were identified, with type i fimbriae such as fim, lpf (long polar fimbriae), tafi (thin ... | 2011 | 21557055 |
| computational investigation of the enzymatic mechanisms of phosphothreonine lyase. | spvc, a virulence effector injected through type iii secretion system by some salmonella serovars, belongs to the newly discovered enzyme family, phosphothreonine lyase. previous experimental studies have demonstrated that spvc irreversibly inactivates mitogen-activated protein kinases by removing the phosphate group from phosphothreonine-containing substrate through a β-elimination mechanism, and results in a β-methyldehydroalanine product. interestingly, further biochemical investigations also ... | 2011 | 21558045 |
| m153r mutation in a ph-sensitive green fluorescent protein stabilizes its fusion proteins. | green fluorescent protein (gfp) and its fusion proteins have been used extensively to monitor and analyze a wide range of biological processes. however, proteolytic cleavage often removes gfp from its fusion proteins, not only causing a poor signal-to-noise ratio of the fluorescent images but also leading to wrong interpretations. | 2011 | 21559297 |
| paneth cell α-defensins in enteric innate immunity. | paneth cells at the base of small intestinal crypts of lieberkühn secrete high levels of α-defensins in response to cholinergic and microbial stimuli. paneth cell α-defensins are broad spectrum microbicides that function in the extracellular environment of the intestinal lumen, and they are responsible for the majority of secreted bactericidal peptide activity. paneth cell α-defensins confer immunity to oral infection by salmonella enterica serovar typhimurium, and they are major determinants of ... | 2011 | 21560070 |
| crystallographic and microcalorimetric analyses reveal the structural basis for high arginine specificity in the salmonella enterica serovar typhimurium periplasmic binding protein stm4351. | | 2011 | 21560168 |
| food-specific attribution of selected gastrointestinal illnesses: estimates from a canadian expert elicitation survey. | abstract the study used a structured expert elicitation survey to derive estimates of food-specific attribution for nine illnesses caused by enteric pathogens in canada. it was based on a similar survey conducted in the united states and focused on campylobacter spp., escherichia coli o157:h7, listeria monocytogenes, nontyphoidal salmonella enterica, shigella spp., vibrio spp., yersinia enterocolitica, cryptosporidium parvum, and norwalk-like virus. a snowball approach was used to identify food ... | 2011 | 21561379 |
| virulotyping of salmonella enterica serovar napoli strains isolated in italy from human and nonhuman sources. | abstract salmonella enterica serovar napoli is an emerging serovar in italy, france, and switzerland, but little is known about its pathogenicity to humans. a collection of 112 strains of salmonella napoli isolated in italy from human cases, foods of animal origin, and the environment have been characterized by the detection of a set of virulence genes, pulsed-field gel electrophoresis (pfge), and antibiotic susceptibility. all the strains examined were susceptible to all the antimicrobials test ... | 2011 | 21561382 |
| receptor-transporter interactions of canonical atp-binding cassette import systems in prokaryotes. | atp-binding cassette (abc) transport systems mediate the translocation of solutes across biological membranes at the expense of atp. they share a common modular architecture comprising two pore-forming transmembrane domains and two nucleotide binding domains. in prokaryotes, abc transporters are involved in the uptake of a large variety of chemicals, including nutrients, osmoprotectants and signal molecules. in pathogenic bacteria, some abc importers are virulence factors. canonical abc import s ... | 2011 | 21561685 |
| quantitative proteomic analysis of salmonella enterica serovar typhimurium under phop/phoq activation conditions. | the phop/phoq two-component system plays a central regulatory role in the pathogenesis of salmonella enterica serovar typhimurium (s. typhimurium), and it can be activated by low mg(2+) concentrations and sublethal concentrations of cationic antimicrobial peptides (camp). therefore, these two phop/phoq activation signals are considered as in vivo environmental cues sensed by s. typhimurium for adaptation and survival. in this work, we conducted a silac (stable isotope labeling by amino acids in ... | 2011 | 21563813 |
| ethidium bromide efflux by salmonella: modulation by metabolic energy, ph, ions and phenothiazines. | the main efflux pump of salmonella enterica serotype enteritidis, which obtains its energy for the extrusion of noxious agents from the proton-motive force, was studied with the aid of an ethidium bromide (etbr) semi-automated method under conditions that define the role of metabolic energy, ions and ph in the extrusion of the universal substrate etbr. the results obtained in this study indicate that in minimal medium containing sodium at ph 5 efflux of etbr is independent of glucose, whereas at ... | 2011 | 21565465 |
| x-ray crystallography and isothermal titration calorimetry studies of the salmonella zinc transporter zntb. | the zntb zn(2+) efflux system is important for maintenance of zn(2+) homeostasis in enterobacteria. we report crystal structures of zntb cytoplasmic domains from salmonella enterica serovar typhimurium (stzntb) in dimeric and physiologically relevant homopentameric forms at 2.3 å and 3.1 å resolutions, respectively. the funnel-like structure is similar to that of the homologous thermotoga maritima cora mg(2+) channel and a vibrio parahaemolyticus zntb (vpzntb) soluble domain structure. however, ... | 2011 | 21565704 |
| nitrous oxide emission and microbial community in the rhizosphere of nodulated soybeans during the late growth period. | we examined n(2)o emissions from the rhizosphere of field-grown soybeans during the late growth stage (99-117 days after sowing). marked emissions were detected from the nodulated root systems of field-grown soybeans, whereas a non-nodulating soybean mutant showed no emission. degraded nodules exclusively generated the n(2)o. a culture-independent analysis of microbial communities showed bradyrhizobium sp., acidvorax facilis, salmonella enterica, xanthomonas sp., enterobacter cloacae, pseudomona ... | 2009 | 21566356 |
| dry-resistance of salmonella enterica subsp. enterica serovar enteritidis is regulated by both sep22, a novel pathogenicity-related factor of salmonella, and nutrients. | environmental isolates of salmonella enterica serover enteritidis (s. enteritidis) clones were grown to the logarithmic phase, washed and re-suspended in saline or luria-bertani (lb) medium, and then 10-µl aliquots of the suspensions were dried overnight at room temperature. the dried bacteria were mixed with 1 ml of ice-cold pbs, suspended and examined for colony-forming activity. all of the pathogenic clones with high levels of sep22, identical to salmonella dps, maintained good viability if s ... | 2009 | 21566364 |
| two efficient methods for the conjugation of smooth-form lipopolysaccharides with probes bearing hydrazine or amino groups. i. lps activation with cyanogen bromide. | this chapter presents a conjugation method for coupling probes bearing hydrazine or primary amino groups to a smooth(s)-form lipopolysaccharide (lps). lps is modified by the activation of the hydroxyl groups present in its o-antigen moiety with cyanogen bromide in aqueous acetone. the method yields conjugates with good labeling ratios, preserving the endotoxic activity of the lipid a moiety. conjugation of smooth-form lps from salmonella enterica sv. minnesota with dansyl hydrazine and horseradi ... | 2011 | 21567325 |
| two efficient methods for the conjugation of smooth-form lipopolysaccharides with probes bearing hydrazine or amino groups. ii. lps activation with a cyanopyridinium agent. | this chapter presents a conjugation method for coupling probes bearing hydrazine or primary amino groups to a lipopolysaccharide (lps). lps is modified by the activation of the hydroxyl groups present in its o-antigen moiety with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (cdap). the method yields conjugates with good labeling ratios, preserving the endotoxic activity of the lipid a moiety. conjugation of smooth-form lps from salmonella enterica sv. minnesota with dansyl hydrazine and h ... | 2011 | 21567326 |
| reemergence of chloramphenicol in typhoid fever in the era of antibiotic resistance. | | 2010 | 21568009 |
| onset of diarrhea and pyrexia and time to detection of salmonella enterica subsp enterica in feces in experimental studies of cattle, horses, goats, and sheep after infection per os. | to determine time to first detection of salmonella organisms in feces of animals after experimental infection po and times to onset of diarrhea and pyrexia to evaluate a common method for identifying nosocomial infections on the basis of time of admission and onset of clinical signs (ie, the 3-day criterion). | 2011 | 21568780 |
| association of attenuated mutants of salmonella enterica serovar enteritidis with porcine peripheral blood leukocytes. | in this study, we were interested in the association of attenuated mutants of salmonella enterica serovar enteritidis with subpopulations of porcine white blood cells (wbc). the mutants included those with inactivated aroa, phop, rfal, rfag, rfac and flic genes and a mutant with five major pathogenicity islands removed (δspi1-5 mutant). using flow cytometry, we did not observe any difference in the interactions of the wild-type s. enteritidis, aroa and phop mutants with wbc. δspi1-5 and flic mut ... | 2011 | 21569080 |
| distribution of salmonella typhimurium in romaine lettuce leaves. | leafy greens are occasionally involved in outbreaks of enteric pathogens. in order to control the plant contamination it is necessary to understand the factors that influence enteric pathogen-plant interactions. attachment of salmonella enterica serovar typhimurium to lettuce leaves has been demonstrated before; however, only limited information is available regarding the localization and distribution of immigrant salmonella on the leaf surface. to extend our knowledge regarding initial pathogen ... | 2011 | 21569943 |
| application of multiple locus variable number of tandem repeat analysis (mlva), phage typing and antimicrobial susceptibility testing to subtype salmonella enterica serovar typhimurium isolated from pig farms, pork slaughterhouses and meat producing plants in ireland. | salmonella enterica subsp. enterica serovar typhimurium is a common zoonotic pathogen encountered in irish pigs and the pork industry and its characterisation using highly discriminatory typing methods is necessary for epidemiological studies, outbreak investigation and control. multiple locus variable number of tandem repeat analysis (mlva), phage typing and antimicrobial susceptibility testing were applied to characterise 301 s. typhimurium isolates of porcine origin isolated from farms, slaug ... | 2011 | 21569956 |
| lps structure influences protein secretion in salmonella enterica. | in this study we have compared protein secretion in the wild type of s. typhimurium and the rfac mutant. we found out that the rfac mutant was defective in protein secretion. in addition, the rfac mutant was defective in its invasion into an ipec-j2 porcine epithelial cell line and also in motility in semisolid agar. consistent with this, reduced flagella numbers were observed in the rfac mutant. in the rfac mutant, there were no defects in flagellin expression as detected by western blot and im ... | 2011 | 21570779 |
| inhibition studies with anions and small molecules of two novel β-carbonic anhydrases from the bacterial pathogen salmonella enterica serovar typhimurium. | two new β-carbonic anhydrases (cas, ec 4.2.1.1) from the bacterial pathogen salmonella enterica serovar typhimurium, stca 1 and stca 2, were characterized kinetically. the two enzymes possess appreciable activity as catalysts for the hydration of co(2) to bicarbonate, with k(cat) of 0.79×10(6)s(-1) and 1.0×10(6)s(-1), and k(cat)/k(m) of 5.2×10(7)m(-1)s(-1) and of 8.3×10(7)m(-1)s(-1), respectively. a large number of simple/complex inorganic anions as well as other small molecules (sulfamide, sulf ... | 2011 | 21570835 |
| subtyping salmonella serovar enteritidis isolates from different sources using sequence typing based on virulence genes and crisprs. | salmonella enterica subsp. enterica serovar enteritidis is a major cause of foodborne salmonellosis in the united states. two major food vehicles for ser. enteritidis are contaminated eggs and chicken meat. improved subtyping methods are needed to accurately track specific strains of ser. enteritidis related to human salmonellosis throughout the chicken and egg food system. a sequence typing scheme based on virulence genes (fimh and ssel) and crisprs (clustered regularly interspaced short palind ... | 2011 | 21571881 |
| population dynamics of salmonella enterica serotypes in commercial egg and poultry production. | fresh and processed poultry have been frequently implicated in cases of human salmonellosis. furthermore, increased consumption of meat and poultry has increased the potential for exposure to salmonella. while advances have been made in reducing the prevalence and frequency of salmonella contamination in processed poultry, there is mounting pressure on commercial growers to prevent and/or eliminate these human pathogens in preharvest production facilities. several factors contribute to salmonell ... | 2011 | 21571882 |
| structural insight into the rotational switching mechanism of the bacterial flagellar motor. | the bacterial flagellar motor can rotate either clockwise (cw) or counterclockwise (ccw). three flagellar proteins, flig, flim, and flin, are required for rapid switching between the cw and ccw directions. switching is achieved by a conformational change in flig induced by the binding of a chemotaxis signaling protein, phospho-chey, to flim and flin. flig consists of three domains, flig(n), flig(m), and flig(c), and forms a ring on the cytoplasmic face of the ms ring of the flagellar basal body. ... | 2011 | 21572987 |
| fur activates the expression of salmonella enterica pathogenicity island 1 by directly interacting with the hild operator in vivo and in vitro. | previous studies have established that the expression of salmonella enterica pathogenicity island 1 (spi1), which is essential for epithelial invasion, is mainly regulated by the hild protein. the ferric uptake regulator, fur, in turn modulates the expression of the s. enterica hild gene, albeit through an unknown mechanism. here we report that s. enterica fur, in its metal-bound form, specifically binds to an at-rich region (boxa), located upstream of the hild promoter (p(hild)), at position -1 ... | 2011 | 21573071 |
| early, myd88-dependent induction of interleukin-17a expression during salmonella colitis. | the development of t helper 17 (t(h)17) cells is a well-established adaptive mechanism for the production of interleukin (il)-17a, a cytokine involved in neutrophil recruitment. however, pathways contributing to mucosal expression of il-17a during the initial phase of a bacterial infection have received less attention. here we used the mouse colitis model of salmonella enterica serotype typhimurium (s. typhimurium) infection to investigate the contribution of myeloid differentiation primary resp ... | 2011 | 21576324 |
| survival of salmonella strains differing in their biofilm-formation capability upon exposure to hydrochloric and acetic acid and to high salt. | acidic and osmotic treatments are part of hurdle systems to control pathogens such as salmonella in food. in the current study, salmonella enterica isolates previously shown to differ in their ability to form biofilms were grown in diluted tryptic soy broth (tsb) (1:5 dilution in distilled water) and subsequently exposed to phosphate-buffered saline (pbs) adjusted to ph 3.0 with hcl, pbs adjusted to ph 3.9 with acetic acid, or rice vinegar diluted 1:15 with distilled water (ph 3.9). cells grown ... | 2011 | 21576891 |
| selectivity of inhibition of n-succinyl-l,l-diaminopimelic acid desuccinylase in bacteria: the product of dape-gene is not the target of l-captopril antimicrobial activity. | the emergence of bacterial strains that are resistant to virtually all currently available antibiotics underscores the importance of developing new antimicrobial compounds. n-succinyl-l,l-diaminopimelic acid desuccinylase (dape) is a metallohydrolase involved in the meso-diaminopimelate (mdap)/lysine biosynthetic pathway necessary for lysine biosynthesis and for building the peptidoglycan cell wall. because dape is essential for gram-negative and some gram-positive bacteria, dape has been propos ... | 2011 | 21577314 |
| helicobacter pylori exhibits a fur-dependent acid tolerance response. | background: helicobacter pylori colonizes the acid environment of the gastric mucosa. like other enteric bacterial pathogens, including salmonella enterica, which must survive a brief exposure to that environment, h. pylori displays a rapid response to subtle changes in ph, which confers an increased ability to survive at more extreme acidic ph. this two-step acid tolerance response (atr) requires de novo protein synthesis and is dependent on the function of the global regulatory protein fur. o ... | 2011 | 21585604 |
| a holin remnant protein encoded by sty1365 is involved in envelope stability of salmonella enterica serovar typhi. | we characterized sty1365, a small orf of salmonella enterica serovar typhi. this 174-bp orf encodes a putative product of 57 amino acid residues with a premature stop codon. nevertheless, bioinformatic analyses revealed that the predicted product of sty1365 has similarity to putative holin genes of escherichia coli and bacteriophage φp27. sty1365 showed a high-level expression at the early log phase and a small corresponding protein product was detected mainly in the inner membrane fraction. clo ... | 2011 | 21592194 |
| oral and nasal dna vaccines delivered by attenuated salmonella typhimurium induce protective immune response against infectious bronchitis in chickens. | several studies have reported that intramuscular injection of dna vaccines against infectious bronchitis virus (ibv) induces protective immune responses. in the present study, we developed oral and nasal dna vaccines that carried the s1 gene and n gene of ibv delivered by attenuated salmonella typhimurium strains, sl/pv-s1 and sl/pv-n, respectively. the safety and stability of recombinant salmonella vaccine were evaluated. following oral and nasal administration of chickens, the serum and mucosa ... | 2011 | 21593235 |
| the population of a high-virulence strain of salmonella enterica serovar enteritidis in subcutaneously infected partridge: a quantitative time-course study using real-time pcr. | this research was undertaken to determine the population of a high-virulence strain of salmonella enterica serovar enteritidis in partridge by a fluorescent quencher pcr assay and to correlate these findings with the results obtained from the immunohistochemical localization and histopathological examinations of selected salmonella enterica serovar enteritidis-infected tissues. to make the results meaningful, a side-by-side bacteriology method (indirect immuno-fluorescent antibody staining) was ... | 2011 | 21594642 |
| a shigella boydii bacteriophage which resembles salmonella phage vii. | abstract: background: lytic bacteriophages have been applied successfully to control the growth of various foodborne pathogens. sequencing of their genomes is considered as an important preliminary step to ensure their safety prior to food applications. results: the lytic bacteriophage, phisbom-ag3, targets the important foodborne pathogen, shigella. it is morphologically similar to phage vii of salmonella enterica serovar typhi and a series of phages of acinetobacter calcoaceticus and rhizobium ... | 2011 | 21595934 |
| comparative genomics of 28 salmonella enterica isolates: evidence for crispr-mediated adaptive sublineage evolution. | despite extensive surveillance, foodborne salmonella enterica infections continue to cause a significant burden on public health systems worldwide. as the s. enterica species comprises sublineages with greatly differing antigenic representation, virulence and antimicrobial resistance phenotypes, a better understanding of the species evolution is critical for the prediction and prevention of future outbreaks. the role that virulence and resistance phenotype acquisition, exchange and loss play for ... | 2011 | 21602358 |
| the long-term persistence of blacmy-2 positive, inca/c plasmids requires selection pressure. | multidrug resistance (mdr), bla(cmy-2) plasmids that confer resistance to third-generation cephalosporins have been found in multiple bacterial species collected from different hosts worldwide. the widespread distribution of bla(cmy-2) plasmids may be driven by antibiotic use that selects for the dissemination and persistence of these plasmids. alternatively, these plasmids may persist and spread in bacterial populations in the absence of selection pressure if a balance exists between conjugativ ... | 2011 | 21602382 |
| the spectrin cytoskeleton is crucial for adherent and invasive bacterial pathogenesis. | various enteric bacterial pathogens target the host cell cytoskeletal machinery as a crucial event in their pathogenesis. despite thorough studies detailing strategies microbes use to exploit these components of the host cell, the role of the spectrin-based cytoskeleton has been largely overlooked. here we show that the spectrin cytoskeleton is a host system that is hijacked by adherent (entropathogenic escherichia coli [epec]), invasive triggering (salmonella enterica serovar typhimurium [s. ty ... | 2011 | 21603579 |
| allb, allantoin utilisation and salmonella enterica serovar enteritidis and typhimurium colonisation of poultry and mice. | natural variation in the presence or the absence of stm0517-0529 genes allowing allantoin utilisation has been described in field isolates of the multidrug resistant salmonella enterica serovar typhimurium belonging to the phage type dt104. interestingly, s. enterica subspecies enterica serovar typhimurium dt104 is quite frequent in pigs and cattle, but rarely present in egg-laying hens. taking into account the different mode of allantoin metabolism in birds and mammals, we were interested in wh ... | 2011 | 21611691 |
| a method to generate recombinant salmonella typhi ty21a strains expressing multiple heterologous genes using an improved recombineering strategy. | live attenuated salmonella enterica serovar typhi ty21a (ty21a) is an important vaccine strain used in clinical studies for typhoid fever and as a vaccine vector for the expression of heterologous antigens. to facilitate the use of ty21a in such studies, it is desirable to develop improved strategies that enable the stable chromosomal integration and expression of multiple heterologous antigens. the phage λ red homologous recombination system has previously been used in various gram-negative bac ... | 2011 | 21611798 |
| comprehensive analysis of salmonella sequence polymorphisms and development of a ldr-ua assay for the detection and characterization of selected serotypes. | salmonella is a major cause of food-borne disease, and salmonella enterica subspecies i includes the most clinically relevant serotypes. salmonella serotype determination is important for the disease etiology assessment and contamination source tracking. this task will be facilitated by the disclosure of salmonella serotype sequence polymorphisms, here annotated in seven genes (sefa, safa, safc, biga, inva, fima, and phsb) from 139 s. enterica strains, of which 109 belonging to 44 serotypes of s ... | 2011 | 21611799 |
| molecular epidemiological investigation of a diffuse outbreak caused by salmonella enterica serotype montevideo isolates in osaka prefecture, japan. | abstract in osaka prefecture, japan, three foodborne outbreaks were caused by salmonella enterica serotype montevideo in rapid succession between september 2007 and may 2008. further, salmonella montevideo was also isolated from several sporadic diarrhea patients and asymptomatic carriers examined during approximately the identical period. to investigate the relatedness of the isolates, we performed antimicrobial susceptibility testing, pulsed-field gel electrophoresis (pfge) analysis, and multi ... | 2011 | 21612424 |
| mycobacterium avium subsp. avium and salmonella enterica serotype typhimurium var. copenhagen phage type dt2 in pigeons. | abstract we report on a coinfection of mycobacterium avium subsp. avium and salmonella enterica serotype typhimurium var. copenhagen phage type dt2 in pigeons from one flock, from which squabs were occasionally consumed by humans. triplex quantitative real-time pcr and culture methods were used for m. a. avium detection in livers and culture method was used for the detection of salmonella sp. in samples of liver and caecum of 33 examined birds. m. a. avium was detected in a total of 31 (93.9%) a ... | 2011 | 21612426 |
| babies and bearded dragons: sudden increase in reptile-associated salmonella enterica serovar tennessee infections, germany 2008. | abstract introduction: in 2008 a marked increase in salmonella enterica serovar tennessee infections in infants occurred in germany. in march and april 2008, eight cases were notified compared to a median of 0-1 cases in 2001-2006. materials and methods: we carried out an investigation including a case-control study to identify the source of infection. a patient was a child <3 years of age with salmonella tennessee isolated from stool from september 1, 2007, through december 31, 2008, identified ... | 2011 | 21612527 |
| salmonella genomic island 1-j variants associated with change in the antibiotic resistance gene cluster in multidrug-resistant salmonella enterica serovar virchow isolated from humans, taiwan, 2004-2006. | clin microbiol infect abstract: salmonella genomic island 1 (variant sgi1-j3) has been previously identified in multi-drug resistant (mdr) salmonella enterica serovar virchow isolated from humans in 1994. in this study, antimicrobial resistance, genotypes and genetic relationship were investigated in 96 s. virchow isolates collected from humans in 2004-2006. xbai-pfge analysis separated 96 isolates into two main related clusters, i and ii, which consisted of four major pulsotypes differing in pr ... | 2011 | 21615827 |
| impact of a probiotic fermented milk in the gut ecosystem and in the systemic immunity using a non-severe protein-energy-malnutrition model in mice. | abstract: background: malnutrition affects the immune response, causing a decrease of defence mechanisms and making the host more susceptible to infections. probiotics can reconstitute the intestinal mucosa and stimulate local and systemic immunity. the aim of this work was evaluate the effects of a probiotic fermented milk as a complement of a re-nutrition diet, on the recovery of the intestinal barrier, and mucosal and systemic immune functions in a murine model of non-severe protein-energy-ma ... | 2011 | 21615956 |
| mouse models to assess the efficacy of non-typhoidal salmonella vaccines: revisiting the role of host innate susceptibility and routes of challenge. | non-typhoidal salmonella enterica (nts) serovars typhimurium and enteritidis are important causes of bacterial gastroenteritis in the usa and worldwide. in sub-saharan africa these two serovars are emerging as agents associated with lethal invasive disease (e.g., bacteremia, meningitis). the development of nts vaccines, based on mucosally administered live attenuated strains and parenteral non-living antigens, could diminish the nts disease burden globally. mouse models of s. typhimurium and s. ... | 2011 | 21616112 |
| phosphorylation of the autophagy receptor optineurin restricts salmonella growth. | selective autophagy can be mediated via receptor molecules that link specific cargoes to the autophagosomal membranes decorated by ubiquitin-like lc3 (microtubule-associated protein light chain 3) modifiers. although several autophagy receptors have been identified, little is known about mechanisms controlling their functions in vivo. here, we found that phosphorylation of an autophagy receptor, optineurin, promoted selective autophagy of ubiquitin-coated cytosolic salmonella enterica. the prote ... | 2011 | 21617041 |
| complete genome sequence of the universal killer, salmonella enterica serovar typhimurium uk-1 (atcc 68169). | the salmonella enterica serovar typhimurium strain uk-1 presents the highest invasion and virulence attributes among the most frequently studied strains. s. typhimurium uk-1 has been used as the foundation for developing recombinant vaccines and been extensively used on virulence and colonization studies in chickens and mice. we describe here the complete genome sequence of s. typhimurium uk-1. comparative genomics of salmonella typhimurium will provide insight into factors that determine virule ... | 2011 | 21622747 |
| humanized mice for salmonella typhi infection: new tools for an old problem. | salmonella enterica serovar typhi (s. typhi), is a human restricted pathogen and the causal agent of typhoid fever. although the use of antimicrobial drugs or vaccines has served as an effective therapeutics strategy against typhoid fever, the recent surge in multidrug resistant strains of s. typhi presents a major health concern worldwide. progress on typhoid research has been limited in the past due to the lack of a suitable animal model that recapitulates the hallmark immunological features o ... | 2011 | 21623167 |
| the salmonella enterica phop directly activates the horizontally acquired spi-2 gene ssel and is functionally different from a s. bongori ortholog. | to establish a successful infection within the host, a pathogen must closely regulate multiple virulence traits to ensure their accurate temporal and spatial expression. as a highly adapted intracellular pathogen, salmonella enterica has acquired during its evolution various virulence genes via numerous lateral transfer events, including the acquisition of the salmonella pathogenicity island 2 (spi-2) and its associated effectors. beneficial use of horizontally acquired genes requires that their ... | 2011 | 21625519 |
| β-glucan plus ascorbic acid in neonatal calves modulates immune functions with and without salmonella enterica serovar dublin. | to determine if β-glucan plus ascorbic acid affects adherence and pathogenicity of salmonella dublin and innate immune response in neonatal calves, 20 calves were fed control or supplemented diets (β-glucan, 0.9g/d, plus ascorbic acid, 500mg/d) until d 23. on d 21, 5 calves per treatment received 2.4×10(8)cfu of s. dublin orally. s. dublin spread through intestinal tissues into mesenteric lymph nodes (mln), spleen, and lung tissues within 48h. all supplemented calves had less mrna expression of ... | 2011 | 21628075 |
| antibodies in action: the role of human opsonins in killing salmonella enterica serovar typhi. | although vaccines have been available for over a century, a correlate of protection for typhoid fever has yet to be identified. antibodies are produced in response to typhoid infection and vaccination, and are generally used as the gold standard for determining vaccine immunogenicity even though their role in clearance of s. typhi infections is poorly defined. herein, we describe the first functional characterization of s. typhi-specific antibodies following vaccination with a new vaccine, m01zh ... | 2011 | 21628517 |