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prevalence of salmonella spp. in cane toads (bufo marinus) from grenada, west indies, and their antimicrobial susceptibility.cloacal swabs and caecal contents sampled from 58 cane toads (bufo marinus) in st george's parish, grenada, during a 7-month period in 2011 were examined by an enrichment and selective culture method for presence of salmonella spp. twenty-four (41%) toads were positive for salmonella spp. of which eight were salmonella enterica serovar javiana, and eight were s. enterica serovar rubislaw. the other serovars were as follows: montevideo, 6; arechavaleta, 1; and serovar: iv:43:-:-, 1. the high freq ...201323035820
salmonella enterica subsp. enterica producing vim-1 carbapenemase isolated from livestock farms. 201323034713
the population structure of salmonella enterica enteritidis in iran analyzed by multiple-locus variable-number tandem repeat analysis.salmonella enterica enteritidis is the most frequent etiological agent of salmonellosis in humans and poultry. to understand the genetic diversity of s. enteritidis in iran, we examined 69 chicken isolates from 18 broiler farms and six non-epidemic human isolates from six geographically distant provinces by multi-locus variable-number tandem repeat analysis (mlva). among se2, se3, se5, se7, se8, sentr4, and sentr7, only se5 with four and sentr7 with two alleles, respectively, proved variable giv ...201323096767
a fresh view of the cell biology of copper in enterobacteria.copper ions are essential but also very toxic. copper resistance in bacteria is based on export of the toxic ion, oxidation from cu(i) to cu(ii), and sequestration by copper-binding metal chaperones, which deliver copper ions to efflux systems or metal-binding sites of copper-requiring proteins. in their publication in this issue, osman et al. (2013) demonstrate how tightly copper resistance, homeostasis and delivery pathways are interwoven in salmonella enterica sv. typhimurium. copper is trans ...201323217080
salmonella enterica serotype bovismorbificans, a new host for ctx-m-9. 201323127480
immunological evaluation of vi capsular polysaccharide of salmonella enterica subsp. typhi vaccine by serum bactericidal assay.salmonella enterica subsp. typhi (s. typhi) vi antigen capsular polysaccharide (vi-cps) is a licensed vaccine against typhoid fever. as there is no animal model for s. typhi fever to evaluate the protective efficacy of the vi-cps vaccine, a serum bactericidal assay (sba) is the recommended 'gold standard' to evaluate its potency. vi-cps was extracted from s. typhi ty6s (csbpi-b191) using a modified gotschlich method. purified vi-cps (50 µg) was injected intramuscularly into three groups of five ...201323105026
anthranilate phosphoribosyl transferase (trpd) generates phosphoribosylamine for thiamine synthesis from enamines and phosphoribosyl pyrophosphate.anthranilate phosphoribosyl transferase (trpd) has been well characterized for its role in the tryptophan biosynthetic pathway. here, we characterized a new reaction catalyzed by trpd that resulted in the formation of the purine/thiamine intermediate metabolite phosphoribosylamine (pra). the data showed that 4- and 5-carbon enamines served as substrates for trpd, and the reaction product was predicted to be a phosphoribosyl-enamine adduct. isotopic labeling data indicated that the trpd reaction ...201323101964
a scalable method for o-antigen purification applied to various salmonella serovars.the surface lipopolysaccharide of gram-negative bacteria is both a virulence factor and a b cell antigen. antibodies against o-antigen of lipopolysaccharide may confer protection against infection, and o-antigen conjugates have been designed against multiple pathogens. here, we describe a simplified methodology for extraction and purification of the o-antigen core portion of salmonella lipopolysaccharide, suitable for large-scale production. lipopolysaccharide extraction and delipidation are per ...201323142430
the "decline and fall" of nontyphoidal salmonella in the united kingdom.remarkable changes in the epidemiology of human nontyphoidal salmonellosis have occurred in the united kingdom over the last century. between 1981 and 1991, the incidence of nontyphoidal salmonellosis in the united kingdom rose by >170%, driven primarily by an epidemic of salmonella enterica subspecies enterica serovar enteritidis phage type (pt) 4, which peaked in 1993. measures introduced to control this epidemic included legislation, food safety advice, and an industry-led vaccination program ...201323166188
first detection of oqxab in salmonella spp. isolated from food.food-borne salmonellosis is an important public health problem worldwide and the second leading cause of food-borne illnesses in hong kong. in this study, the prevalence and antimicrobial resistance of salmonella in meat products in hong kong were determined. interestingly, a plasmid-mediated quinolone resistance (pmqr) gene combination, oqxab, which mediates resistance to nalidixic acid, chloramphenicol, and olaquindox, was for the first time detectable on the chromosomes of two salmonella ente ...201323147728
salmonella serotype diversity and seasonality in urban and rural streams.to investigate the prevalence, seasonality and genetic diversity of salmonella enterica serotypes, particularly those of human and veterinary health significance, in urban and rural streams.201323167768
the b subunit of an ab5 toxin produced by salmonella enterica serovar typhi up-regulates chemokines, cytokines, and adhesion molecules in human macrophage, colonic epithelial, and brain microvascular endothelial cell lines.the principal function of bacterial ab5 toxin b subunits is to interact with glycan receptors on the surfaces of target cells and mediate the internalization of holotoxin. however, b subunit-receptor interactions also have the potential to impact cell signaling pathways and, in so doing, contribute to pathogenesis independently of the catalytic (toxic) a subunits. various salmonella enterica serovars, including salmonella enterica serovar typhi, encode an ab5 toxin (artab), the a subunit of whic ...201323250951
salmonella enterica serovar typhi variants in long-term carriers.long-term typhoid carriers can simultaneously excrete salmonella enterica serovar typhi variants with considerable genetic differences, a situation that complicates the interpretation of the subtyping data used in outbreak investigations and disease surveillance.201323241373
phenotypic and genetic traits of salmonella enterica subsp. serovar typhimurium strains causing salmonellosis foci in rabbit farms from southern italy in 1999-2003.in this study, we characterised the salmonella typhimurium strains responsible for four outbreaks which occurred in distinct rabbit farms (southern italy) from 1999 to 2003. strains were typed by pulsed field gel electrophoresis (pfge) and the genetic basis of antimicrobial resistance was established. a major group of clonally related isolates, pulsotype stymxb.0061, accounted for three of the salmonellosis foci. strains were resistant to streptomycin, chloramphenicol, tetracycline, ampicillin a ...201323178046
utilization and accessibility of healthcare on pemba island, tanzania: implications for health outcomes and disease surveillance for typhoid fever.salmonella enterica serotype typhi (s. typhi) was estimated to cause over 200,000 deaths and more than 21 million illnesses worldwide, including over 400,000 illnesses in africa. the current study was conducted in four villages on pemba island, zanzibar, in 2010. we present data on policy makers', health administrators', and village residents' and leaders' perceptions of typhoid fever, and hypothetical and actual health care use among village residents for typhoid fever. qualitative data provide ...201323208887
a dry-inoculation method for nut kernels.a dry-inoculation method for almonds and walnuts was developed to eliminate the need for the postinoculation drying required for wet-inoculation methods. the survival of salmonella enterica enteritidis pt 30 on wet- and dry-inoculated almond and walnut kernels stored under ambient conditions (average: 23 °c; 41 or 47% rh) was then compared over 14 weeks. for wet inoculation, an aqueous salmonella preparation was added directly to almond or walnut kernels, which were then dried under ambient cond ...201323200663
colonization of internal organs by salmonella enteritidis in experimentally infected laying hens housed in conventional or enriched cages.more human illnesses caused by salmonella enterica subspecies enterica serovar enteritidis throughout the world have been linked to the consumption of contaminated eggs than to any other food vehicle. deposition of this pathogen in the edible contents of eggs occurs when systemic infections of laying hens involve colonization of reproductive organs. in recent years, the consequences of different housing systems for laying flocks have become the focus of international attention from both animal w ...201323300315
an essential serotype recognition pocket on phage p22 tailspike protein forces salmonella enterica serovar paratyphi a o-antigen fragments to bind as nonsolution conformers.bacteriophage p22 recognizes o-antigen polysaccharides of salmonella enterica subsp. enterica (s.) with its tailspike protein (tsp). in the serovars s. typhimurium, s. enteritidis, and s. paratyphi a, the tetrasaccharide repeat units of the respective o-antigens consist of an identical main chain trisaccharide but different 3,6-dideoxyhexose substituents. here, the epimers abequose, tyvelose and paratose determine the specific serotype. p22 tsp recognizes o-antigen octasaccharides in an extended ...201323292517
occurrence of β-lactamase genes among non-typhi salmonella enterica isolated from humans, food animals, and retail meats in the united states and canada.non-typhi salmonella cause over 1.7 million cases of gastroenteritis in north america each year, and food-animal products are commonly implicated in human infections. for invasive infections, antimicrobial therapy is indicated. in north america, the antimicrobial susceptibility of salmonella is monitored by the u.s. national antimicrobial resistance monitoring system (narms) and the canadian integrated program for antimicrobial resistance surveillance (cipars). in this study, we determined the s ...201323289438
β-lactamases, transferable quinolone resistance determinants, and class 1 integron-mediated antimicrobial resistance in human clinical salmonella enterica isolates of non-typhimurium serotypes.this work investigates the occurrence and features of class 1 integrons and the presence of transferable quinolone resistance determinants (tqrd) among 382 clinical salmonella enterica isolates of non-typhimurium serotypes as well as the β-lactamases produced by amoxicillin-resistant isolates. these isolates were recovered in 2001 and from 2004 to 2009 from patients from the health region of terres de l'ebre (catalonia, spain) and comprised 41 different serotypes, mostly of serovar enteritidis ( ...201323273534
a weibull model to describe antimicrobial kinetics of oregano and lemongrass essential oils against salmonella enteritidis in ground beef during refrigerated storage.the antimicrobial effect of oregano (origanum vulgare l.) and lemongrass (cymbopogon citratus (dc.) stapf.) essential oils (eos) against salmonella enterica serotype enteritidis in in vitro experiments, and inoculated in ground bovine meat during refrigerated storage (4±2 °c) for 6 days was evaluated. the weibull model was tested to fit survival/inactivation bacterial curves (estimating of p and δ parameters). the minimum inhibitory concentration (mic) value for both eos on s. enteritidis was 3. ...201323273476
systemic exposure, tissue distribution, and disease evolution of a high solubility ciprofloxacin-aluminum complex in a murine model of septicemia induced by salmonella enterica serotype enteritidis.a new pharmaceutical derivative obtained by stoichiometric complexation of ciprofloxacin (cip) with aluminum (cip-complex) has been investigated and reported in this study. such product has high solubility in the gastrointestinal ph range and was successful in the development of optimized formulations while maintaining its antimicrobial potency. the systemic exposure, tissue distribution, and the disease evolution after given cip-complex were assessed. the systemic exposure and distribution in i ...201323273286
inflammatory responses to salmonella infections are serotype-specific.the main purpose of this study was to investigate the profile of inflammatory response in patients with acute salmonellosis caused by two serotypes of salmonella enterica, s. enteritidis and s. typhimurium, as well as in convalescent patients with previous acute disease caused by s. enteritidis. patients with acute disease showed significantly elevated levels of il-1β, il-17, il-10, and calprotectin compared to healthy control subjects. in convalescent patients, these markers were also significa ...201326904722
a rapid, multiplexed, high-throughput flow-through membrane immunoassay: a convenient alternative to elisa.this paper describes a rapid, high-throughput flow-through membrane immunoassay (fmia) platform. a nitrocellulose membrane was spotted in an array format with multiple capture and control reagents for each sample detection area, and assay steps were carried out by sequential aspiration of sample and reagents through each detection area using a 96-well vacuum manifold. the fmia provides an alternate assay format with several advantages over elisa. the high surface area of the membrane permits hig ...201326835678
salmonella enterica serotype typhi infections in a canadian pediatric hospital: a retrospective case series.in developed countries, typhoid fever generally occurs in travellers or recent immigrants from endemic areas. our aim was to describe the epidemiology of salmonella enterica serotype typhi infections among children presenting to a pediatric teaching hospital in montréal, quebec.201325077103
antimicrobial susceptibility and multi-drug resistance of salmonella enterica subspecies enterica serovars in sudan.this study was undertaken to determine the antimicrobial resistance patterns of salmonella enterica subspecies enterica recovered from human, food, water, and animal samples collected in khartoum state, sudan. a total of 64 salmonella isolates belonging to 28 different serovars were tested for their susceptibility to 13 antimicrobial agents. the majority of isolates (98.4 %) were resistant to at least one antimicrobial agent. isolates were frequently resistant to ampicillin (90.6 %), cephalexin ...201323271416
microbiological study of biofilm formation in isolates of salmonella enterica typhimurium dt104 and dt104b cultured from the modern pork chain.the purpose of this study was to characterise 172 salmonella typhimurium isolates taken from the pork chain for their biofilm forming abilities and to analyse their potential to survive on food processing surfaces. many salmonella have the ability to form biofilms. these natural structures, elaborated by bacteria are important in food production because their formation contributes to bacterial survival. adherent bacterial cells are more resilient to displacement strategies including physical and ...201323266499
sero- and genotyping of salmonella in slaughter pigs, from farm to cutting plant, with a focus on the slaughter process.the objective of this study was to investigate the role of the slaughtering process in salmonella carcass contamination by typing isolates recovered previously in a double study of the following: (1) a tracking survey from the farm to the slaughterhouse and (2) a survey of the slaughterhouse environment (i.e., lairage area, slaughter line, cutting plant and carcasses). the salmonella serotypes identified on the carcasses of the 16 tracked batches were frequently linked to lairage, whereas the se ...201323261811
safety and protective efficacy of live attenuated salmonella gallinarum mutants in rhode island red chickens.salmonella enterica serovar gallinarum is the causative agent of fowl typhoid, an important systemic disease of poultry with economic consequences in developing nations. a live attenuated orally applied s. gallinarum vaccine could provide a low cost method for controlling this disease. we constructed s. gallinarum strains in which the expression of the crp, rfc and rfah genes, important for virulence of salmonella typhimurium in mice, were under the control of an arabinose-regulated promoter. we ...201323261043
antimicrobial activity of plant essential oils against escherichia coli o157:h7 and salmonella on lettuce.foodborne outbreaks associated with the consumption of fresh produce have increased. in an effort to identify natural antimicrobial agents as fresh produce-wash, the effect of essential oils in reducing enteric pathogens on iceberg and romaine lettuce was investigated. lettuce pieces were inoculated with a five-strain cocktail of escherichia coli o157:h7 or salmonella enterica (5 log cfu/g) and then immersed in a treatment solution containing 5 ppm free chlorine, cinnamaldehyde, or sporan(®) (80 ...201323256843
growth of salmonella enterica in foliar pesticide solutions and its survival during field production and postharvest handling of fresh market tomato.to evaluate in vitro the growth kinetics of salmonella enterica in pesticide solutions labelled for fresh market tomato and the effect of ag-chemical application with contaminated water to tomatoes during field production.201323360242
dissemination of antimicrobial-resistant clones of salmonella enterica among domestic animals, wild animals, and humans.non-typhoidal salmonellosis is an important zoonotic disease caused by salmonella enterica. this work focuses on the identification of salmonella enterica clonal strains which, presenting a wide distribution potential, express resistance determinants that compromise effectiveness of the antimicrobial therapy. the screening was performed on 506 salmonella enterica isolates from animals and humans, which were characterized by serovar and phage typing, genome macrorestriction and pulsed-field gel e ...201323360170
microfluidic chip-based detection and intraspecies strain discrimination of salmonella serovars derived from whole blood of septic mice.salmonella is a zoonotic pathogen that poses a considerable public health and economic burden in the united states and worldwide. resultant human diseases range from enterocolitis to bacteremia to sepsis and are acutely dependent on the particular serovar of salmonella enterica subsp. enterica, which comprises over 99% of human-pathogenic s. enterica isolates. point-of-care methods for detection and strain discrimination of salmonella serovars would thus have considerable benefit to medical, vet ...201323354710
antimicrobial resistance genes in multidrug-resistant salmonella enterica isolated from animals, retail meats, and humans in the united states and canada.salmonella enterica is a prevalent foodborne pathogen that can carry multidrug resistance (mdr) and pose a threat to human health. identifying the genetics associated with mdr in salmonella isolated from animals, foods, and humans can help determine sources of mdr in food animals and their impact on humans. s. enterica serovars most frequently carrying mdr from healthy animals, retail meats, and human infections in the united states and canada were identified and isolates resistant to the larges ...201323350745
contribution of thy1+ nk cells to protective ifn-γ production during salmonella typhimurium infections.ifn-γ is critical for immunity against infections with intracellular pathogens, such as salmonella enterica. however, which of the many cell types capable of producing ifn-γ controls salmonella infections remains unclear. using a mouse model of systemic salmonella infection, we observed that only a lack of all lymphocytes or cd90 (thy1)(+) cells, but not the absence of t cells, retinoic acid-related orphan receptor (ror)-γt-dependent lymphocytes, (nk)1.1(+) cells, natural killer t (nkt), and/or ...201323345426
reassessing the type i dehydroquinate dehydratase catalytic triad: kinetic and structural studies of glu86 mutants.dehydroquinate dehydratase (dhqd) catalyzes the third reaction in the biosynthetic shikimate pathway. type i dhqds are members of the greater aldolase superfamily, a group of enzymes that contain an active site lysine that forms a schiff base intermediate. three residues (glu86, his143, and lys170 in the salmonella enterica dhqd) have previously been proposed to form a triad vital for catalysis. while the roles of lys170 and his143 are well defined-lys170 forms the schiff base with the substrate ...201323341204
outbreak of salmonella typhi enteric fever in sub-urban area of north india: a public health perspective.outbreaks of enteric fever are a major health concern not only due to significant human morbidity and mortality but also fear of spread of multidrug resistant strains. we report an outbreak of enteric fever caused by salmonella enterica serotype typhi in a suburban area, in city chandigarh of north india. twenty-seven strains of s. typhi were isolated from blood cultures over a period of two weeks with 18 of these 27 patients residing in the same area. maximum cases were in the age group 5-14 ye ...201323339924
a t-bet gradient controls the fate and function of ccr6-rorγt+ innate lymphoid cells.at mucosal surfaces, the immune system should not initiate inflammatory immune responses to the plethora of antigens constantly present in the environment, but should remain poised to unleash a potent assault on intestinal pathogens. the transcriptional programs and regulatory factors required for immune cells to switch from homeostatic (often tissue-protective) function to potent antimicrobial immunity are poorly defined. mucosal retinoic-acid-receptor-related orphan receptor-γt-positive (rorγt ...201323334414
long-term survival of escherichia coli o157:h7 and salmonella enterica on butterhead lettuce seeds, and their subsequent survival and growth on the seedlings.the long-term survival of enteric pathogens on butterhead lettuce seeds, and their subsequent survival and growth on seedlings were investigated. lettuce seeds were inoculated at a high level with two salmonella enterica and two escherichia coli o157:h7 strains each (±8 log₁₀ cfu/g seed) and the survival of the pathogens was monitored over two years using standard plating techniques on selective medium. the salmonella strains (serovars typhimurium and thompson) survived significantly better on t ...201323334101
current antibiogram and clonal relatedness among drug-resistant salmonella enterica serovar typhi in northern india.in view of the changing sensitivity pattern of salmonella, this study was carried out to investigate the current antibiogram and clonal relatedness among the drug-resistant salmonella enterica serovar typhi in northern india.201323330551
characterization of salmonella food isolates with concurrent resistance to ceftriaxone and ciprofloxacin.foodborne salmonellosis is an important public health problem worldwide. most human salmonella infections occur through the consumption of contaminated food of animal origin. the study reported the first isolation of two salmonella enterica serovar oranienburg strains from pork in china with concurrent resistance to ciprofloxacin and ceftriaxone. both isolates also showed resistance to norfloxacin, trimethoprim-sulfamethoxazole, and chloramphenicol, and an elevated minimal inhibitory concentrato ...201323320422
initial contamination of chicken parts with salmonella at retail and cross-contamination of cooked chicken with salmonella from raw chicken during meal preparation.the current study was undertaken to acquire data on contamination of chicken parts with salmonella at retail and to acquire data on cross-contamination of cooked chicken with salmonella from raw chicken during meal preparation. whole raw chickens (n = 31) were obtained from local retail stores and cut into two wings, two breasts without skin or bones, two thighs, and two drumsticks. data for cross-contamination were obtained by cutting up a sterile, cooked chicken breast with the same board and ...201323317854
antimicrobial resistance of salmonella enterica isolates from bulk tank milk and milk filters in the united states.salmonella isolates were recovered from bulk tank milk as part of the national animal health monitoring system (nahms) dairy 2002 and 2007 surveys. in-line milk filters were also tested in the 2007 survey. the objective of this study was to determine the prevalence of antimicrobial resistance among salmonella enterica isolates from bulk milk and milk filters in the nahms dairy 2002 and 2007 surveys and to further characterize resistant isolates. susceptibilities to 15 antibiotics were determined ...201323317852
a genomewide mutagenesis screen identifies multiple genes contributing to vi capsular expression in salmonella enterica serovar typhi.a transposon-based, genomewide mutagenesis screen exploiting the killing activity of a lytic viii bacteriophage was used to identify salmonella enterica serovar typhi genes that contribute to vi polysaccharide capsule expression. genes enriched in the screen included those within the viab locus (tviabcde and vexabcde) as well as oxyr, bara/sira, and yrff, which have not previously been associated with vi expression. the role of these genes in vi expression was confirmed by constructing defined n ...201323316043
reactive arthritis following salmonella infection: a population-based study.to study the incidence and clinical picture of salmonella-associated reactive arthritis (rea), as well as other reactive musculoskeletal symptoms and the arthritogenicity of various salmonella enterica ssp. enterica serotypes in the population.201323311895
lack of effect of the salmonella deubiquitinase ssel on the nf-κb pathway.intracellular replication of salmonella enterica requires effector proteins translocated across the salmonella-containing vacuolar membrane by salmonella pathogenicity island-2 (spi-2) encoded type iii secretion system (t3ss). the spi-2 t3ss effector ssel is a deubiquitinase that contributes to virulence in mice. previous work has produced conflicting evidence as to the involvement of ssel in interference with the nf-κb pathway. to attempt to clarify these discrepancies, we compared mrna levels ...201323308136
role of the salmonella enterica serovar typhi fur regulator and small rnas rfra and rfrb in iron homeostasis and interaction with host cells.iron is an essential element but can be toxic at high concentrations. therefore, its acquisition and storage require tight control. salmonella encodes the global regulator fur (ferric uptake regulator) and the small regulatory non-coding rnas (srnas) rfra and rfrb, homologues of ryhb. the role of these iron homeostasis regulators was investigated in salmonella enterica serovar typhi (s. typhi). strains containing either single or combined deletions of these regulators were obtained. the mutants ...201323306672
hunanamycin a, an antibiotic from a marine-derived bacillus hunanensis.hunanamycin a, the first natural product with a pyrido[1,2,3-de]quinoxaline-2,3-dione core, was isolated from a marine-derived bacillus hunanensis. hunanamycin a is related to a degradation product of riboflavin but has undergone an n-prenylation and subsequent cyclization. the structure, including stereochemistry, was determined by nmr and ms methods. hunanamycin a exhibits a minimum inhibitory concentration (mic) of 12.4 μm against the bacterial pathogen salmonella enterica.201323305153
isolation of salmonella mutants resistant to the inhibitory effect of salicylidene acylhydrazides on flagella-mediated motility.salicylidene acylhydrazides identified as inhibitors of virulence-mediating type iii secretion systems (t3sss) potentially target their inner membrane export apparatus. they also lead to inhibition of flagellar t3ss-mediated swimming motility in salmonella enterica serovar. typhimurium. we show that inp0404 and inp0405 act by reducing the number of flagella/cell. these molecules still inhibit motility of a salmonella δflih-flii-flij/flhb((p28t)) strain, which lacks three soluble components of th ...201323300965
use of real-time pcr on faecal samples for detection of sub-clinical salmonella infection in cattle did not improve the detection sensitivity compared to conventional bacteriology.there is a need for more sensitive detection methods to improve effectiveness of control programmes of salmonella enterica subsp. enterica serotypes (salmonella) in cattle. we assessed the performance of a rapid, molecular-based, real-time pcr (rt-pcr) method against the conventional bacteriological culture-reference method (bcrm) on cattle faecal samples for detection of sub-clinical salmonella infections in cattle. thirty faecal samples were artificially contaminated with either 10 or 50 cfu o ...201323391438
identification and typing of salmonella enterica serotypes isolated from guinea fowl (numida meleagris) farms in benin during four laying seasons (2007 to 2010).the main problem for the local guinea fowl (numida meleagris) traditional farming and raising system in north-east benin is the high mortality rate of the keets (up to 70%) due to a combination of climatic, nutritional, hygienic and infectious causes. the present study was carried out to identify and compare the isolates of salmonella enterica from necropsied keets, laying guinea fowl, surrogate hen mothers, other contact animal species and farmers during four laying seasons (2007 to 2010). s. e ...201323391175
decline in ciprofloxacin-resistant salmonella enterica serovar choleraesuis in taiwan, 2001-2011. 201323390070
deletion in the c-terminal domain of clpx delayed entry of salmonella enterica into a viable but non-culturable state.under stressful conditions, bacteria enter a viable but non-culturable (vbnc) state in which they are alive but fail to grow on conventional media. the molecular basis underlying this state is unknown. to identify the key gene responsible for the vbnc state in salmonella spp., we examined a s. typhimurium lt2 vbnc mutant, which shows a characteristic delay in entering the vbnc state. the mutant showed a higher level of expression of general stress sigma factor rpos than wild-type lt2. the mutant ...201323385142
diversity of salmonella enterica serovar typhi strains collected from india using variable number tandem repeat (vntr)-pcr analysis.typhoid fever is endemic in india, and a seasonal increase of cases is observed annually. in spite of effective therapies and the availability of vaccines, morbidity is widespread owing to the circulation of multiple genetic variants, frequent migration of asymptomatic carriers, unhygienic food practices and the emergence of multidrug resistance and thus continues to be a major public health problem in developing countries, particularly in india. classical methods of strain typing such as pulsed ...201323615945
characterization of salmonella enterica subsp. enterica serovar 4,[5],12:i:- clones isolated from human and other sources in switzerland between 2007 and 2011.salmonella enterica subsp. enterica serovar 4,[5],12:i:- is a monophasic variant of salmonella typhimurium. in this study, a total of 651 human and 107 food and environmental isolates of serovar 4,[5],12:i:- recovered from 2007 through 2011 in switzerland were characterized by antibiotic resistance profiles and pulsed-field gel electrophoresis (pfge). in addition, a selection of isolates belonging to the most frequent pfge patterns was further subjected to multilocus variable-number tandem-repea ...201323614800
decreased ciprofloxacin susceptibility in salmonella typhi and paratyphi infections in ill-returned travellers: the impact on clinical outcome and future treatment options.the emergence of decreased ciprofloxacin susceptibility (dcs) in salmonella enterica serovar typhi and serovar paratyphi a, b or c limits treatment options. we studied the impact of dcs isolates on the fate of travellers returning with enteric fever and possible alternative treatment options. we evaluated the clinical features, susceptibility data and efficacy of empirical treatment in patients with positive blood cultures of a dcs isolate compared to patients infected with a ciprofloxacin-susce ...201323609512
prevalence, characterization and antimicrobial susceptibility of salmonella enterica and yersinia enterocolitica in pigs at slaughter in italy.in 2005-2008, 1152 samples (451 faecal samples, 451 carcass swabs and 250 tonsils) were collected from 451 finishing pigs slaughtered in three abattoirs of northern italy. in two abattoirs, 34 scalding water samples were collected. the aim of this study was to investigate the faecal and palatine tonsil carriage rate of salmonella enterica and yersinia enterocolitica in pigs at slaughter and the degree of carcass contamination by these bacteria. typing of the isolates, virulence characterization ...201323603278
prevalence and genetic analysis of phenotypically vi- negative salmonella typhi isolates in children from kathmandu, nepal.the vi capsular polysaccharide (vips) protects salmonella enterica subspecies enterica serotype typhi (s.typhi) in vivo by multiple mechanisms. recent microbiological reports from typhoid endemic countries suggest that acapsulate s.typhi may occur in nature and contribute to clinical typhoid fever that is indistinguishable from disease caused by capsulate strains. the prevalence and genetic basis of vips-negative s.typhi isolates in children from kathmandu, nepal, were tested in 68 isolates. alt ...201323598894
prospects for prevention of salmonella infection in children through vaccination.strains of salmonella enterica subsp. enterica are amongst the most commonly identified invasive bacterial pathogens in resource-poor settings, and cause significant mortality, particularly in children. in this study we review recent progress in the development of vaccines against s. typhi, s. paratyphi and nontyphoidal salmonella for children.201323591641
evidence that a metabolic microcompartment contains and recycles private cofactor pools.microcompartments are loose protein cages that encapsulate enzymes for particular bacterial metabolic pathways. these structures are thought to retain and perhaps concentrate pools of small, uncharged intermediates that would otherwise diffuse from the cell. in salmonella enterica, a microcompartment encloses enzymes for ethanolamine catabolism. the cage has been thought to retain the volatile intermediate acetaldehyde but allow diffusion of the much larger cofactors nad and coenzyme a (coa). ge ...201323585538
primers with 5' flaps improve the efficiency and sensitivity of multiplex pcr assays for the detection of salmonella and escherichia coli o157:h7.foodborne illnesses caused by salmonella enterica and escherichia coli o157:h7 are worldwide health concerns. rapid, sensitive, and robust detection of these pathogens in foods and in clinical and environmental samples is essential for routine food quality testing, effective surveillance, and outbreak investigations. the aim of this study was to evaluate the effect on pcr sensitivity of adding a short, at-rich overhanging nucleotide sequence (flap) to the 5' end of pcr primers specific for the d ...201323575131
salmonella enterica biofilm formation and density in the centers for disease control and prevention's biofilm reactor model is related to serovar and substratum.foodborne pathogens can attach to, and survive on, food contact surfaces for long periods by forming a biofilm. salmonella enterica is the second most common cause of foodborne illness in ireland. the ability of s. enterica to form a biofilm could contribute to its persistence in food production areas, leading to cross-contamination of products and surfaces. arising from a large foodborne outbreak of s. enterica serovar agona associated with a food manufacturing environment, a hypothesis was for ...201323575130
comparison of an isothermal amplification and bioluminescence detection of dna method and iso 6579:2002 for the detection of salmonella enterica serovars in retail meat samples.the aim of the study was the comparative evaluation of an isothermal amplification and bioluminescence detection of dna (imbd) method and method iso 6579:2002 for detection of salmonella in retail meat products of unknown contamination status. a total of 200 meat samples were tested: 116 minced meat and meat preparations to be eaten cooked (52 chicken, 48 pork, and 16 beef samples) and 84 fresh meat samples (68 poultry and 16 pork). with one or both methods, 21 samples (10.5%) were positive for ...201323575129
comparative analysis of the susceptibility to triclosan and three other biocides of avian salmonella enterica isolates collected 1979 through 1994 and 2004 through 2010.few studies have been conducted on changes in the susceptibility of bacteria due to long-term use of biocides. a total of 375 avian salmonella isolates collected in germany from healthy or diseased animals during two time periods, 1979 through 1994 and 2004 through 2010, were included in the present study. the isolates were tested for their mics of triclosan, acriflavine, benzalkonium chloride, and chlorhexidine by broth macrodilution. mic50, mic90, and the distribution of mics were compared. th ...201323575128
cross-sectional study examining salmonella enterica carriage in subiliac lymph nodes of cull and feedlot cattle at harvest.bovine peripheral lymph nodes (lns), including subiliac lns, have been identified as a potential source of human exposure to salmonella enterica, when adipose trim containing these nodes is incorporated into ground beef. in order to gain a better understanding of the burden of s. enterica in peripheral lns of feedlot and cull cattle, a cross-sectional study was undertaken in which 3327 subiliac lns were collected from cattle at harvest in seven plants, located in three geographically distinct re ...201323566273
detection and differentiation of foodborne pathogenic bacteria in mung bean sprouts using field deployable label-free sers devices.vancomycin functionalized silver nanorod arrays substrates were used to obtain the surface enhanced raman scattering (sers) signals of six foodborne pathogenic bacteria in mung bean sprouts samples using both a portable and a handheld raman system. the silver nanorod arrays substrates were optimized to facilitate quantitative, rapid, and sensitive detection of salmonella enterica serotype anatum, salmonella enterica serotype cubana, salmonella enterica serotype stanley, salmonella enteritidis, e ...201323563168
structural insight into the giant ca²⁺-binding adhesin siie: implications for the adhesion of salmonella enterica to polarized epithelial cells.siie from salmonella enterica is a giant 5,559-residue-long nonfimbrial adhesin that is secreted by a type 1 secretion system (t1ss) and initiates bacterial adhesion to polarized host cells. structural insight has been gained into the 53 bacterial ig-like (big) domains of siie, which account for 94% of the entire siie sequence. the crystal structure of a fragment comprising big domains 50 to 52 of siie reveals the big domain architecture and highlights two types of siie-specific ca²⁺-binding sit ...201323562396
molecular clonality and antimicrobial resistance in salmonella enterica serovars enteritidis and infantis from broilers in three northern regions of iran.multidrug-resistant salmonella strains are frequently encountered problems worldwide with considerable increased occurrences in recent years. the aim of this study was to investigate the occurrence and frequency of antimicrobial resistance and associated resistance genes in salmonella isolates from broiler farms in different regions of iran covering a time period of four years.201323561048
simultaneous detection of salmonella pathogenicity island 2 and its antibiotic resistance genes from seafood.salmonella enterica serovars are virulent pathogens of humans and animals with many strains possessing multiple drug resistance traits. they have been found to carry resistance to ampicillin, chloramphenicol, florfenicol, streptomycin, sulfonamides, and tetracycline (acssut-resistant). a rapid and sensitive multiplex pcr (mpcr)-based assay was developed for the detection of salmonella serovars from seafood. six sets of primers which are one primer pair targeting salmonella specific gene inva (28 ...201323545447
regional distribution of two dairy-associated salmonella enterica serotypes.salmonella enterica is a zoonotic pathogen that is often associated with dairy farms. the organism can cause disease in cows but is also frequently shed in large numbers by dairy cows that are asymptomatic. long-term asymptomatic infections with serotypes cerro and kentucky were previously identified in cows on a 100-head dairy farm in pennsylvania, united states (focal dairy). milk filters were collected from farms within 30 miles of the focal dairy to determine whether the infections by cerro ...201323536986
application of scutellariae radix, gardeniae fructus, and probiotics to prevent salmonella enterica serovar choleraesuis infection in swine.salmonella enterica serovar choleraesuis, a host-adapted pathogen of swine, usually causes septicemia. lactic acid bacteria (lab) strains have been widely studied in recent years for their probiotic properties. in this study, a mouse infection model first screened for potential agents against infection, then a pig infection model evaluated effects of lab strains and herbal plants against infection. scutellariae radix (sr) and gardeniae fructus (gf) showed abilities to reduce bacteria shedding an ...201323533497
salmonella enterica isolated from pigeon (columba livia) in egypt.understanding the association between human salmonellosis cases and animal sources is an important epidemiological factor needed to successfully control the spread of the infection within communities. to determine the extent to which pigeons might harbor this pathogen and pose a risk to the human population in egypt, we screened pigeons in cairo for the presence of salmonella relevant to public health and antimicrobial susceptibility testing. the isolated serotypes recovered from pigeon fecal sa ...201323531124
the role of flagella and chemotaxis genes in host pathogen interaction of the host adapted salmonella enterica serovar dublin compared to the broad host range serovar s. typhimurium.the importance of flagella and chemotaxis genes in host pathogen interaction in salmonella enterica is mainly based on studies of the broad host range serovar, s. typhimurium, while little is known on the importance in host specific and host adapted serovars, such as s. dublin. in the current study we have used previously characterized insertion mutants in flagella and chemotaxis genes to investigate this and possible differences in the importance between the two serovars.201323530934
the antimicrobial effects of cinnamon leaf oil against multi-drug resistant salmonella newport on organic leafy greens.there is generally no kill-step when preparing salad vegetables, so there is a greater risk for foodborne illness from contaminated vegetables. some essential oils have antimicrobial activities and could provide a natural way to reduce pathogens on fresh produce. the objective of this study was to investigate the antimicrobial activity of cinnamon oil wash against salmonella enterica serotype newport on organic leafy greens. organic romaine and iceberg lettuce, and organic baby and mature spinac ...201323911760
mig-14 plays an important role in influencing gene expression of salmonella enterica serovar typhi, which contributes to cell invasion under hyperosmotic conditions.mig-14 is a horizontally acquired host-induced virulence gene in salmonella enterica serovar typhi. the molecular function of mig-14 is still unknown; sequence analysis showed that mig-14 shared homology with the helix-loop-helix motif of the arac family of transcriptional regulatory proteins. in our previous microarray-based studies, mig-14 was upregulated at the early stage of high osmotic stress, indicating a potential role under this condition. therefore, we compared growth and the global tr ...201323911675
fimh adhesin from host unrestricted salmonella enteritidis binds to different glycoprotein ligands expressed by enterocytes from sheep, pig and cattle than fimh adhesins from host restricted salmonella abortus-ovis, salmonella choleraesuis and salmonella dublin.adhesion to gut tissues and colonization of the alimentary tract, two important stages in the pathogenesis of salmonella, are mediated by fimh adhesin of type 1 fimbriae. it was suggested that minor differences in the structure of fimh are most likely associated with differences in adhesion specificities, and may determine the tropism of various salmonella serovars to different species and tissues. we investigated this hypothesis by comparing the binding properties of fimh proteins from three sa ...201323910950
comparing the roles of antibodies to nontyphoidal salmonella enterica in high- and low-income countries and implications for vaccine development. 201323904457
[antimicrobial susceptibility of animal and food isolates of salmonella enterica].bacterial resistance to one or more antimicrobiak is worrisome.201323900319
synthesis, antibacterial and thermal studies of cellulose nanocrystal stabilized zno-ag heterostructure nanoparticles.synthesis of zno-ag heterostructure nanoparticles was carried out by a precipitation method with cellulose nanocrystals (cncs) as a stabilizer for antimicrobial and thermal studies. zno-ag nanoparticles were obtained from various weight percentages of added agno₃ relative to zn precursors for evaluating the best composition with enhanced functional properties. the zno-ag/cncs samples were characterized systematically by tem, xrd, uv, tga and dtg. from the tem studies we observed that zno-ag hete ...201323760028
characterization of salmonella isolated from captive and free-living snakes in germany.reptiles are well-known reservoirs of salmonella spp. and cases of reptile-associated salmonellosis (ras) are increasing since reptiles are becoming more popular as pets. in the present study, the presence, distribution and prevalence of serovars of salmonella was investigated in captive snakes (n = 87) and in free-living snakes (n = 87) in germany. a total of 43 s. enterica-isolates were recovered from organ samples and cloacal swabs, predominantly belonging to the subspecies diarizonae (iiib) ...201323758035
salmonella infections in reptiles--prevalence, serovar spectrum and impact on animal health.in a seven year study, 235 lizards, 193 snakes and 111 chelonians were tested for the occurrence of salmonella enterica. the material for analysis consisted of 251 faecal samples from reptiles suffering from diarrhoea and 288 carcasses of perished or euthanized reptiles. the carcasses were dissected and examined pathohistologically. a total of 35.3% of the lizards, 47.2% of the snakes and 11.7% of the chelonians were found to be salmonella-positive. systemic salmonella infection was detected in ...201323758034
salmonella septic arthritis of the knees in a patient with systemic lupus erythematosus.hematogenous salmonella osteomyelitis is uncommon in immunocompetent hosts, but occurs with some regularity in immunosuppressed patients affected by systemic lupus erythematosus (sle). surgical debridement with resection of compromised tissue is central to the surgical management of osteomyelitis. persistence of septic arthropathy may result from inadequate debridement, areas of osteonecrosis (on), and an abnormal cellular and humoral dysregulation characteristic of sle. we describe a 53-year-ol ...201323753601
in the absence of rida, endogenous 2-aminoacrylate inactivates alanine racemases by modifying the pyridoxal 5'-phosphate cofactor.members of the rida (yjgf/yer057c/uk114) protein family are broadly conserved across the domains of life. in vitro, these proteins deaminate 3- or 4-carbon enamines that are generated as mechanistic intermediates of pyridoxal 5'-phosphate (plp)-dependent serine/threonine dehydratases. the three-carbon enamine 2-aminoacrylate can inactivate some enzymes by forming a covalent adduct via a mechanism that has been well characterized in vitro. the biochemical activity of rida suggested that the pheno ...201323749972
the teta gene decreases tigecycline sensitivity of salmonella enterica isolates.to determine the association of tetracycline resistance determinants with tigecycline sensitivity, tetracycline-resistant salmonella spp. isolated from clinical and food samples were tested for the presence of tetracycline resistance determinants, tigecycline sensitivity, and the impact of teta on tigecycline resistance. in addition, the impacts of multiple resistance mechanisms on tigecycline resistance were determined using an isolate with ramr mutation. of the 49 tetracycline-resistant salmon ...201323746717
contribution of different mechanisms to the resistance to fluoroquinolones in clinical isolates of salmonella enterica.to study the potential factors include gene mutation, efflux pump and alteration of permeability associated with quinolone-resistance of salmonella enterica strains isolated from patients with acute gastroenteritis and to evaluate the degree of synergistic activity of efflux pump inhibitors when combined with ciprofloxacin against resistant isolates.201323742803
identification of the yfgf mase1 domain as a modulator of bacterial responses to aspartate.complex 3'-5'-cyclic diguanylic acid (c-di-gmp) responsive regulatory networks that are modulated by the action of multiple diguanylate cyclases (dgc; ggdef domain proteins) and phosphodiesterases (pde; eal domain proteins) have evolved in many bacteria. yfgf proteins possess a membrane-anchoring domain (mase1), a catalytically inactive ggdef domain and a catalytically active eal domain. here, sustained expression of the salmonella enterica spp. enterica ser. enteritidis yfgf protein is shown to ...201323740576
co-occurrence of acssut and cephalosporin resistance phenotypes is mediated by int1-associated elements in nontyphoidal salmonella enterica from human infections in spain.a screening of antimicrobial resistance and its genetic determinants has been performed on 300 salmonella enterica isolates collected during 2004-2008 from human infections in spain. salmonella typhimurium and salmonella enteritidis were the major serotypes, which were found with similar frequencies covering 80% of the bacterial collection. salmonella typhimurium isolates frequently shared low susceptibility to antimicrobials of the penta-resistance phenotype (acssut) and/or cephalosporin resist ...201323738829
ciprofloxacin-resistant salmonella enterica serovar kentucky in canada.we report emergence of ciprofloxacin-resistant salmonella enterica serovar kentucky in canada during 2003-2009. all isolates had similar macrorestriction patterns and were multilocus sequence type st198, which has been observed in europe and africa. ciprofloxacin-resistant s. enterica serovar kentucky represents 66% of all ciprofloxacin-resistant nontyphoidal salmonella sp. isolates observed in canada since 2003.201323735312
assignment of serotype to salmonella enterica isolates obtained from poultry and their environment in southern brazil.to assess diversity of salmonella enterica serotypes present in poultry and their environment from southern brazil, the kauffmann-white-le minor (kwl) scheme was used to serotype a total of 155 isolates. isolates were then re-examined with nested pcr and sequencing of the dkgb-linked intergenic sequence ribotyping (isr) region that assesses single nucleotide polymorphisms occurring around a 5s ribosomal gene. serotypes identified were heidelberg (40·6%), enteritidis (34·2%), hadar (8·4%), typhim ...201323734786
chronological change of resistance to β-lactams in salmonella enterica serovar infantis isolated from broilers in japan.epidemiologic surveillance study was conducted in southern japan to determine the antimicrobial resistance phenotypes and characterize the β-lactamase genes and the plasmids harboring these genes in salmonella enterica serovar infantis (s. infantis) isolates from broilers. between january, 2007 and december, 2008, a total of 1,472 fecal samples were collected and examined at the laboratory of veterinary public health, kagoshima university, japan. in 93 (6.3%) isolates recovered, 33 (35.5%) isola ...201323734146
distribution of six effector protein virulence genes among salmonella enterica enterica serovars isolated from children and their correlation with biofilm formation and antimicrobial resistance.salmonella enterica enterica encodes a variety of virulence factors. among them, the type iii secretion system (ttss) encoded in the salmonella pathogenicity islands (spis) is required for induction of proinflammatory responses, invasion of intestinal epithelial cells, induction of cell death in macrophages, and elicitation of diarrhea. the presence of the effector protein genes sopb, sopd, sope, sope2, avra, and sptp of the spis was analyzed in 194 s. enterica enterica strains belonging to 19 s ...201323733519
protein signatures that promote operator selectivity among paralog merr monovalent metal ion regulators.two paralog transcriptional regulators of the merr family, cuer and gols, are responsible for monovalent metal ion sensing and resistance in salmonella enterica. although similar in sequence and also in their target binding sites, these proteins differ in signal detection and in the set of target genes they control. recently, we demonstrated that selective promoter recognition depends on the presence of specific bases located at positions 3' and 3 within the operators they interact with. here, w ...201323733186
increased water activity reduces the thermal resistance of salmonella enterica in peanut butter.increased water activity in peanut butter significantly (p < 0.05) reduced the heat resistance of desiccation-stressed salmonella enterica serotypes treated at 90 °c. the difference in thermal resistance was less notable when strains were treated at 126 °c. using scanning electron microscopy, we observed minor morphological changes of s. enterica cells resulting from desiccation and rehydration processes in peanut oil.201323728806
validation of a predictive model for survival and growth of salmonella typhimurium dt104 on chicken skin for extrapolation to a previous history of frozen storage.the u.s. department of agriculture's tertiary pathogen modeling program (pmp) model for survival and growth of salmonella enterica ser. typhimurium definitive type 104 (dt104) on chicken skin stored for 0 to 8 h at 5 to 50°c was evaluated for its ability to predict survival and growth of the same organism on chicken skin after frozen storage for 6 days at -20°c. experimental design and methods used to collect data for model development (dependent data) were the same as those used to collect data ...201323726201
effect of lime juice on vibrio parahaemolyticus and salmonella enterica inactivation during the preparation of the raw fish dish ceviche.ceviche is a raw fish dish common in peru and other latin american counties. the most characteristic feature of ceviche is the use of lime juice for marinating or "cooking" the raw fish. confirmed cases of cholera in peru, new jersey, and florida have been associated with ceviche. although the effect of organic acids on pathogenic bacteria has been well characterized, few data exist on the effect of these acids in seafood systems. the objective of the study was to evaluate the effects of lime ju ...201323726199
comparative genomics of salmonella enterica serovars derby and mbandaka, two prevalent serovars associated with different livestock species in the uk.despite the frequent isolation of salmonella enterica sub. enterica serovars derby and mbandaka from livestock in the uk and usa little is known about the biological processes maintaining their prevalence. statistics for salmonella isolations from livestock production in the uk show that s. derby is most commonly associated with pigs and turkeys and s. mbandaka with cattle and chickens. here we compare the first sequenced genomes of s. derby and s. mbandaka as a basis for further analysis of the ...201323725633
highly drug-resistant salmonella enterica serotype kentucky st198-x1: a microbiological study.salmonella enterica is a major global food-borne pathogen, causing life-threatening infections. ciprofloxacin and extended-spectrum cephalosporins (escs) are the drugs of choice for severe infections. we previously reported a ciprofloxacin-resistant s. enterica serotype kentucky (s kentucky) st198-x1 strain that emerged in egypt and spread throughout africa and the middle east from 2002 to 2008. we aimed to monitor recent trends in the location of transmission and antimicrobial resistance of thi ...201323721756
first report of salmonella enterica serovar infantis in common swifts (apus apus).forty common swifts (apus apus), synanthropic birds living in an urban environment closely with humans and other animals, were hospitalized in the public veterinary hospital of the regional reference center of urban veterinary hygiene located in naples, campania region, italy. each bird was sampled for bacteriological analyses. out of 40 common swifts examined, eight were found positive for salmonella enterica serovar infantis although no sign of salmonellosis (e.g. diarrhoea) was shown. this is ...201323721074
[search for new potential rna thermometers in the salmonella enterica genome]. 201323718050
emergence of multidrug-resistant salmonella enterica serotype 4,[5],12:i:- involving human cases in canada: results from the canadian integrated program on antimicrobial resistance surveillance (cipars), 2003-10.over the last decade, a marked increase in salmonella enterica serotype 4,[5],12:i:- with a core resistance to ampicillin, streptomycin, sulphonamides and tetracycline (assut) has been observed in europe. this study describes the emergence and characterization of isolates of multidrug-resistant salmonella 4,[5],12:i:- in canada.201323710071
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