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horizontal acquisition of a multidrug-resistance module (r-type assut) is responsible for the monophasic phenotype in a widespread clone of salmonella serovar 4,[5],12:i:.salmonella enterica serovar 4,[5],12:i:- is a monophasic variant of s. typhimurium incapable of expressing the second-phase flagellar antigen (fljab operon), and it is recognized to be one of the most prevalent serovars causing human infections. a clonal lineage characterized by phage type dt193, pulsenet pfge profile stymxb.0131 and multidrug resistance to ampicillin, streptomycin, sulphonamides and tetracycline (r-type assut) is commonly circulating in europe. in this study we determined the d ...201627242707
engineering of a live salmonella enterica serovar choleraesuis negative-marker strain that allows serological differentiation between immunised and infected animals.the usefulness of salmonella vaccine vehicles is limited by the fact that control programmes relying on salmonella bacteriology and serology cannot differentiate infected animals from vaccinated ones, an ability referred to as diva (differentiating infected from vaccinated animals). as a first step towards salmonella-based diva vaccines, the ompa gene was deleted in live attenuated δphop and δrpos vaccine strains. the ompa gene is present in all salmonella enterica serovars and it encodes an abu ...201627240916
genetically similar isolates of salmonella enterica serotype enteritidis persistent in china for a long-term period.salmonella enterica serotype enteritidis (s. enteritidis) is an important causative agent of nontyphoidal salmonellosis in human populations. in this study, we collected 72 s. enteritidis strains from 2004 to 2014 in ningbo, mid-east china. of the 72 strains, we identified a dominant clone of 58 strains recovered from patient's feces (n = 48), blood (n = 1), pleural effusion (n = 1), chickens (n = 3), and dessert cakes (n = 5) by pulsed-field gel electrophoresis (pfge) and variable-number of tan ...201627228342
investigating salmonella eko from various sources in nigeria by whole genome sequencing to identify the source of human infections.twenty-six salmonella enterica serovar eko isolated from various sources in nigeria were investigated by whole genome sequencing to identify the source of human infections. diversity among the isolates was observed and camel and cattle were identified as the primary reservoirs and the most likely source of the human infections.201627228329
tiny turtles purchased at pet stores are a potential high risk for salmonella human infection in the valencian region, eastern spain.turtles may be considered unsafe pets, particularly in households with children. this study aimed to assess salmonella carriage by turtles in pet stores and in private ownership to inform the public of the potential health risk, enabling informed choices around pet selection. during the period between september and october 2013, 24 pet stores and 96 private owners were sampled in the valencian region (eastern spain). salmonella identification procedure was based on iso 6579: 2002 recommendations ...201627228194
genomic and phenotypic analyses reveal the emergence of an atypical salmonella enterica serovar senftenberg variant in china.human infections with salmonella enterica subspecies enterica serovar senftenberg are often associated with exposure to poultry flocks, farm environments, or contaminated food. the recent emergence of multidrug-resistant isolates has raised public health concerns. in this study, comparative genomics and phenotypic analysis were used to characterize 14 salmonella senftenberg clinical isolates recovered from multiple outbreaks in shenzhen and shanghai, china, between 2002 and 2011. single-nucleoti ...201627225410
images in clinical medicine. salmonella enterica aortitis. 201627223163
revisit of fluoroquinolone and azithromycin susceptibility breakpoints for salmonella enterica serovar typhi.in recent years, increase in occurrence of fluoroquinolone (fq)-resistant s almonella typhi isolates has caused considerable inconvenience in selecting appropriate antimicrobials for treatment of typhoid. the world health organization (who) recommends azithromycin for the empirical treatment option of uncomplicated typhoid. the clsi updated the breakpoints of disc diffusion (dd) and mic results of fqs and azithromycin for salmonella typhi in 2015, but dd breakpoints of ofloxacin and levofloxacin ...201627221661
interferon-driven alterations of the host's amino acid metabolism in the pathogenesis of typhoid fever.enteric fever, caused by salmonella enterica serovar typhi, is an important public health problem in resource-limited settings and, despite decades of research, human responses to the infection are poorly understood. in 41 healthy adults experimentally infected with wild-type s. typhi, we detected significant cytokine responses within 12 h of bacterial ingestion. these early responses did not correlate with subsequent clinical disease outcomes and likely indicate initial host-pathogen interactio ...201627217537
heat resistance of salmonella enterica is increased by pre-adaptation to peanut oil or sub-lethal heat exposure.cross-protection represents a considerable challenge in the food industry where hurdled interventions are often employed to reduce salmonella contamination. the heat resistance of salmonella strains from five serotypes (i.e., typhimurium, enteritidis, tennessee, thompson and hartford) at 70 °c was determined by measurement of viable cell populations before and after adaptation to two common stresses employed in low-water activity food processing, desiccation and sub-lethal heat treatment. surviv ...201627217370
effects of citrox and chitosan on the survival of escherichia coli o157:h7 and salmonella enterica in vacuum-packaged turkey meat.in this study, we examined the antimicrobial effects of citrus extract (citrox(®)) and chitosan on lactic acid bacteria (lab) and the pathogens escherichia coli o157:h7 and salmonella enterica on turkey meat during storage under vacuum packaging (vp) at 4 and 10 °c. we also examined the effects of citrox and chitosan on pathogen contamination in tryptic soy broth (tsb). chitosan alone or in combination with citrox inhibited the growth of endogenous lab in turkey meat, whereas citrus extract did ...201627217368
modeling the long-term kinetics of salmonella survival on dry pet food.due to multiple outbreaks and large-scale product recalls, salmonella has emerged as a priority pathogen in dry pet food and treats. however, little data are available to quantify risks posed by these classes of products to both pets and their owners. specifically, the kinetics of salmonella survival on complex pet food matrices are not available. this study measured the long-term kinetics of salmonella survival on a dry pet food under storage conditions commonly encountered during production, r ...201627217351
molecular identification of salmonella enterica subsp. enterica serovar gallinarum biovars gallinarum and pullorum by a duplex pcr assay.salmonella enterica subsp. enterica serovar gallinarum biovar gallinarum (s gallinarum) and biovar pullorum (s pullorum) are 2 poultry pathogens that cause major economic losses to the poultry industry worldwide. control of both diseases mainly relies on the adoption of biosecurity programs, and success is dependent on accurate and fast detection. based on this concept, we developed a duplex pcr assay, targeting 2 chromosomal sequences, which allowed us to precisely identify and differentiate s ...201627216724
a centrifugal direct recombinase polymerase amplification (direct-rpa) microdevice for multiplex and real-time identification of food poisoning bacteria.in this study, we developed a centrifugal direct recombinase polymerase amplification (direct-rpa) microdevice for multiplex and real-time identification of food poisoning bacteria contaminated milk samples. the microdevice was designed to contain identical triplicate functional units and each unit has four reaction chambers, thereby making it possible to perform twelve direct-rpa reactions simultaneously. the integrated microdevice consisted of two layers: rpa reagents were injected in the top ...201627216297
characterization of a small outbreak of salmonella enterica serovar infantis that harbour ctx-m-65 in ecuador. 201727215783
serodiagnosis of acute typhoid fever in nigerian pediatric cases by detection of serum iga and igg against hemolysin e and lipopolysaccharide.inexpensive, easy-to-use, and highly sensitive diagnostic tests are currently unavailable for typhoid fever. to identify candidate serodiagnostic markers, we have probed microarrays displaying the full salmonella enterica serovar typhi (s. typhi) proteome of 4,352 different proteins + lipopolysaccharides (lpss), with sera from nigerian pediatric typhoid and other febrile cases, nigerian healthy controls, and healthy u.s. adults. nigerian antibody profiles were broad (∼500 seropositive antigens) ...201627215295
rflm mediates target specificity of the rcscdb phosphorelay system for transcriptional repression of flagellar synthesis in salmonella enterica.the bacterial flagellum enables directed movement of salmonella enterica towards favorable conditions in liquid environments. regulation of flagellar synthesis is tightly controlled by various environmental signals at transcriptional and post-transcriptional levels. the flagellar master regulator flhd4 c2 resides on top of the flagellar transcriptional hierarchy and is under autogenous control by flhd4 c2 -dependent activation of the repressor rflm. the inhibitory activity of rflm depends on the ...201627206164
effect of reduced graphene oxide-hybridized zno thin films on the photoinactivation of staphylococcus aureus and salmonella enterica serovar typhi.the immobilization of photocatalyst nanoparticles on a solid substrate is an important aspect for improved post-treatment separation and photocatalyst reactor design. in this study, we report the simple preparation of reduced graphene oxide (rgo)-hybridized zinc oxide (zno) thin films using a one-step electrochemical deposition, and investigated the effect of rgo-hybridization on the photoinactivation efficiency of zno thin films towards staphylococcus aureus (s. aureus) and salmonella enterica ...201627203568
mechanisms of salmonella typhi host restriction.salmonella enterica serovar typhi (s. typhi) is the cause of typhoid fever, a life-threatening bacterial infection that is very common in the developing world. recent spread of antimicrobial resistant isolates of s. typhi makes typhoid fever, a global public health risk. despite being a common disease, still very little is known about the molecular mechanisms underlying typhoid fever and s. typhi pathogenesis. in contrast to other salmonellae, s. typhi can only infect humans. the molecular bases ...201627193549
salmonella enterica subspecies diarizonae maxillary sinusitis in a snake handler: first report.in this study, we report the first case of reptile-associated maxillary sinusitis due to salmonella enterica subspecies diarizonae in a snake handler and the third case of salmonella-associated sinusitis worldwide. the case highlights the potential of respiratory transmission and atypical salmonellosis presentations.201627186588
immune response of turkey poults exposed at 1 day of age to either attenuated or wild salmonella strains.salmonellosis is a foodborne zoonosis that is most often acquired by consuming poultry products such as eggs and poultry meat. amongst other measures the vaccination of food-producing poultry is thought to contribute to a reduction in human salmonellosis. in the european union (eu) in 2014 the licence of a commercially available salmonella vaccine for chickens and ducks was extended to turkeys. in the present study, we examined the course of infection with a virulent salmonella enterica ssp. ent ...201627185257
a prime-boost immunization with tc52 n-terminal domain dna and the recombinant protein expressed in pichia pastoris protects against trypanosoma cruzi infection.we have previously reported that the n-terminal domain of the antigen tc52 (ntc52) is the section of the protein that confers the strongest protection against trypanosoma cruzi infection. to improve vaccine efficacy, we conducted here a prime-boost strategy (ntc52pb) by inoculating two doses of pcdna3.1 encoding the ntc52 dna carried by attenuated salmonella (sntc52), followed by two doses of recombinant ntc52 expressed in picchia pastoris plus odn-cpg as adjuvant. this strategy was comparativel ...201627177947
a novel procedure on next generation sequencing data analysis using text mining algorithm.next-generation sequencing (ngs) technologies have provided researchers with vast possibilities in various biological and biomedical research areas. efficient data mining strategies are in high demand for large scale comparative and evolutional studies to be performed on the large amounts of data derived from ngs projects. topic modeling is an active research field in machine learning and has been mainly used as an analytical tool to structure large textual corpora for data mining.201627177941
composing a tumor specific bacterial promoter.systemically applied salmonella enterica spp. have been shown to invade and colonize neoplastic tissues where it retards the growth of many tumors. this offers the possibility to use the bacteria as a vehicle for the tumor specific delivery of therapeutic molecules. specificity of such delivery is solely depending on promoter sequences that control the production of a target molecule. we have established the functional structure of bacterial promoters that are transcriptionally active exclusivel ...201627171245
house sparrows do not constitute a significant salmonella typhimurium reservoir across urban gradients in flanders, belgium.in recent decades major declines in urban house sparrow (passer domesticus) populations have been observed in north-western european cities, whereas suburban and rural house sparrow populations have remained relatively stable or are recovering from previous declines. differential exposure to avian pathogens known to cause epidemics in house sparrows may in part explain this spatial pattern of declines. here we investigate the potential effect of urbanization on the development of a bacterial pat ...201627168186
molecular analysis of fluoroquinolone resistance in salmonella enterica serovar typhi from a breast abscess case. 201727166067
construction and characterization of a cigr deletion mutant of salmonella enterica serovar pullorum.salmonella enterica serovar pullorum (s. pullorum) is the causative agent of pullorum disease (pd) and results in severe economic losses to the poultry industry. as a salmonella type iii secretion system 2 (t3ss2) effector and predicted membrane protein, cigr is encoded by the cigr gene within salmonella pathogenicity island 3 (spi3). in order to research the influence of the cigr gene on s. pullorum, a cigr mutant of s. pullorum s06004 was constructed by the lambda red recombination system, and ...201627163262
non-typhoidal salmonella colonization in chickens and humans in the mekong delta of vietnam.salmonellosis is a public health concern in both the developed and developing countries. although the majority of human non-typhoidal salmonella enterica (nts) cases are the result of foodborne infections or person-to-person transmission, nts infections may also be acquired by environmental and occupational exposure to animals. while a considerable number of studies have investigated the presence of nts in farm animals and meat/carcasses, very few studies have investigated the risk of nts coloni ...201727152998
genome sequences of salmonella enterica subsp. enterica serovar lubbock strains isolated from liver abscesses of feedlot cattle.the genome sequencing of 13 salmonella enterica subsp. enterica serovar lubbock strains isolated from liver abscesses of feedlot cattle is reported here. the availability of these genomes will help to further understand the etiologic role of salmonella strains in liver abscesses of cattle and will serve as references in microbial trace-back studies to improve food safety.201627151794
draft genome sequences of 37 salmonella enterica strains isolated from poultry sources in nigeria.here, we report the availability of draft genomes of several salmonella serotypes, isolated from poultry sources from nigeria. these genomes will help to further understand the biological diversity of s. enterica and will serve as references in microbial trace-back studies to improve food safety.201627151793
a multischool outbreak due to salmonella enterica serovar napoli associated with elevated rates of hospitalizations and bacteremia, milan, italy, 2014.a multischool outbreak of salmonellosis caused by salmonella enterica serovar napoli was investigated in the province of milan from october to november 2014, following an increase in school absenteeism coinciding with two positive cases. epidemiological studies detected 47 cases in four primary schools: 46 children and 1 adult woman (51.4% males and 48.6% females, median age 8.9). from these, 14 cases (29.8%) were severe and resulted in hospitalization, including 6 children (12.8%) who developed ...201627148636
chitin mixed in potting soil alters lettuce growth, the survival of zoonotic bacteria on the leaves and associated rhizosphere microbiology.chitin is a promising soil amendment for improving soil quality, plant growth, and plant resilience. the objectives of this study were twofold. first, to study the effect of chitin mixed in potting soil on lettuce growth and on the survival of two zoonotic bacterial pathogens, escherichia coli o157:h7 and salmonella enterica on the lettuce leaves. second, to assess the related changes in the microbial lettuce rhizosphere, using phospholipid fatty acid (plfa) analysis and amplicon sequencing of a ...201627148242
preventing invasive salmonellosis in children through vaccination.vaccination is an important strategy to control endemic enteric fever (ef) and to interrupt transmission during outbreaks. the main aim of this paper is to discuss the efficacy of available ef vaccines in children and to highlight novel vaccination possibilities against ef and non-typhoid invasive salmonelloses.201627140662
altered virulence potential of salmonella enteritidis cultured in different foods: a cumulative effect of differential gene expression and immunomodulation.salmonella enterica serovars enteritidis (s. enteritidis) is one of the most common causes of food borne illness. bacterial growth environment plays an important role in regulating gene expression thereby affecting the virulence profile of the bacteria. different foods present diverse growth conditions which may affect the pathogenic potential of the bacteria. in the present study, the effect of food environments on the pathogenic potential of s. enteritidis has been evaluated. s. enteritidis wa ...201627132148
salmonella pneumonia complicated with encysted empyema in an immunocompromised youth: case report and literature review.in this case report we described a bahraini male patient of twenty years of age, a smoker and diagnosed with stage iv b hodgkin lymphoma. he presented with fever, nonproductive cough, upper back pain and shortness of breath due to right upper lobe pneumonia with right encysted pleural effusion. salmonella enterica serotype enteritidis was isolated from the sputum. he was successfully treated with 2 weeks of ceftriaxone followed by 2 weeks of oral cefixime. this was the first case of encysted emp ...201627131011
carriage prevalence of salmonella enterica serotype typhi in gallbladders of adult autopsy cases from mozambique.typhoid fever is an important public health problem in many low-income countries where asymptomatic carriers play an important role in its dissemination. the bacterium causing typhoid fever can live in the gallstones of asymptomatic persons after the infection. these carriers are reservoirs of s. typhi, are highly contagious, and spread the disease through the secretion of bacteria in feces and urine. the aim of this study was to determine the carrier rate in an area of mozambique.201627131005
emergence of host-adapted salmonella enteritidis through rapid evolution in an immunocompromised host.host adaptation is a key factor contributing to the emergence of new bacterial, viral and parasitic pathogens. many pathogens are considered promiscuous because they cause disease across a range of host species, while others are host-adapted, infecting particular hosts(1). host adaptation can potentially progress to host restriction where the pathogen is strictly limited to a single host species and is frequently associated with more severe symptoms. host-adapted and host-restricted bacterial cl ...201627127642
emergence of blactx-m-15, blatem-169 and blaper-1 extended-spectrum β-lactamase genes among different salmonella enterica serovars from human faecal samples.broad-spectrum β-lactams are used for empirical therapy of severe infections with non-typhoid salmonella serotypes; however, activities of these drugs against the strains producing different β-lactamase is not so clear. this study investigated the prevalence of β-lactamase genes among isolates of s. enterica serovars from human faecal samples and determined their diversity in activity against different β-lactams.201627117981
analysis of the fluoroquinolone antibiotic resistance mechanism of salmonella enterica isolates.quinolone-resistant salmonella strains were isolated from patient samples, and several quinolone-sensitive strains were used to analyze mutations in the quinolone resistance-determining region (qrdr) of gyra, gyrb, parc, and pare and to screen for plasmid-mediated quinolone resistance. among the 21 strains that showed resistance to nalidixic acid and ciprofloxacin (mic 0.125-2.0 μg/ml), 17 strains had a mutation in qrdr codon 87 of gyra, and 3 strains had a single mutation (ser83 → phe). another ...201627116992
nosocomial outbreak of a novel extended-spectrum β-lactamase salmonella enterica serotype isangi among surgical patients.objective nosocomial outbreaks caused by salmonella are rare. we describe the investigation and control of a cluster of novel extended-spectrum β-lactamase (esbl) salmonella enterica serotype isangi in a hospital in southeastern michigan. methods an epidemiologic investigation, including case-control study, assessment of infection control practices and environmental cultures, was performed to identify modes of transmission. healthcare workers (hcws) exposed to case patients were screened. strain ...201627108715
mp-v1 from the venom of social wasp vespula vulgaris is a de novo type of mastoparan that displays superior antimicrobial activities.mastoparans from the venom of social wasps have attracted considerable attention as effective antibiotic candidates. in this study, mastoparan v1 (mp-v1) from vespula vulgaris was first disclosed to have a peptide amino acid sequence distinct from typical mastoparans and its biochemical properties and antimicrobial effects were compared with those of typical mastoparans mp-l, -x(v) and -b. circular dichroism (cd) spectroscopy revealed that mp-v1 and -x(v) form more stable α-helical conformations ...201627104500
draft genome sequences of salmonella enterica subsp. enterica serovar berta atcc 8392 and a nalidixic acid-resistant isolate of this strain.italic! salmonella entericasubspecies italic! entericaserovar berta has been isolated in multiple animal species and has been implicated in human disease. here, we report a 4.7-mbp draft genome sequence of italic! s. entericaserovar berta (atcc strain 8392) and a nalidixic acid-resistant isolate derived from this strain.201627103707
generation of a naïve human single chain variable fragment (scfv) library for the identification of monoclonal scfv against salmonella typhi hemolysin e antigen.antibody phage display is a useful tool for the isolation and identification of monoclonal antibodies. naive antibody libraries are able to overcome the limitations associated with the traditional hybridoma method for monoclonal antibody generation. antibody phage display is also a preferred method for antibody generation against toxins as it does not suffer from toxicity mediated complications. here, we describe a naïve multi ethnic scfv antibody library generated via two-step cloning with an e ...201627090555
genome sequence of the fish pathogen yersinia ruckeri sc09 provides insights into niche adaptation and pathogenic mechanism.yersinia ruckeri is the etiologic agent of enteric red mouth disease (erm), a severe fish disease prevailing in worldwide aquaculture industries. here we report for the first time the complete genome of y. ruckeri (yersinia ruckeri) sc09, a highly virulent strain isolated from ictalurus punctatus with severe septicemia. sc09 possesses a single chromosome of 3,923,491 base pairs, which contains 3651 predicted protein coding sequences (cds), 19 rrna genes, and 79 trna genes. among the cds, we have ...201627089334
serotypes and antimicrobial resistance of salmonella enterica isolated from pork, chicken meat and lettuce, bangkok and central thailand.food of animal origins, particularly pork and chicken meat, has long been recognized as major sources of human salmonellosis. there have been recent reports of human salmonellosis outbreaks due to consumption of leafy green vegetables such as lettuce. in this study, 120 (40 pork, 40 chicken meat and 40 lettuce) samples were randomly collected from retail markets in bangkok and central thailand during june to august 2015 for salmonella serotype identification and antimicrobial susceptibility test ...201627086423
status of paratyphoid fever vaccine research and development.salmonella enterica serovars typhi and paratyphi (s. paratyphi) a and b cause enteric fever in humans. of the paratyphoid group, s. paratyphi a is the most common serovar. in 2000, there were an estimated 5.4 million cases of s. paratyphi a worldwide. more recently paratyphoid fever has accounted for an increasing fraction of all cases of enteric fever. although vaccines for typhoid fever have been developed and in use for decades, vaccines for paratyphoid fever have not yet been licensed. sever ...201627083427
transmissible plasmid containing salmonella enterica heidelberg isolates modulate cytokine production during early stage of interaction with intestinal epithelial cells.the variation in cytokine production during bacterial invasion of human intestinal epithelial cells (iecs) is a contributing factor for progression of the infection. a few salmonella enterica heidelberg strains isolated from poultry products harbor transmissible plasmids (tps), including those that encode a type-iv secretion system. earlier, we showed that these tps are responsible for increased virulence during infection. this study examines the potential role of these tps in cytokine productio ...201627082282
the type three secreted effector sipc regulates the trafficking of perp during salmonella infection.salmonella enterica typhimurium employs type iii secreted effectors to induce cellular invasion and pathogenesis. we previously reported the secreted effector sipa is in part responsible for inducing the apical accumulation of the host membrane protein perp, a host factor we have shown is key to the inflammatory response induced by salmonella. we now report that the s. typhimurium type iii secreted effector sipc significantly contributes to perp redistribution to the apical membrane surface. to ...201627078059
salmonella infection and carriage in reptiles in a zoological collection.objective to identify important subspecies and serovars of salmonella enterica in a captive reptile population and clinically relevant risk factors for and signs of illness in salmonella-positive reptiles. design retrospective cross-sectional study. animals 11 crocodilians (4 samples), 78 snakes (91 samples), 59 lizards (57 samples), and 34 chelonians (23 samples) at the bronx zoo from 2000 through 2012. procedures data pertaining to various types of biological samples obtained from reptiles wit ...201627074614
transfer rna bound to mnmh protein is enriched with geranylated trna--a possible intermediate in its selenation?the wobble nucleoside 5-methylaminomethyl-2-thio-uridine (mnm5s2u) is present in bacterial trnas specific for lys and glu and 5-carboxymethylaminomethyl-2-thio-uridine (cmnm5s2u) in trna specific for gln. the sulfur of (c)mnm5s2u may be exchanged by selenium (se)-a reaction catalyzed by the selenophosphate-dependent trna 2-selenouridine synthase encoded by the mnmh (ybbb, selu, sufy) gene. the mnmh protein has a rhodanese domain containing one catalytic cys (c97) and a p-loop domain containing a ...201627073879
dksa-dependent transcriptional regulation in salmonella experiencing nitrosative stress.redox-based signaling is fundamental to the capacity of bacteria to sense, and respond to, nitrosative and oxidative stress encountered in natural and host environments. the conserved rna polymerase regulatory protein dksa is a thiol-based sensor of reactive nitrogen and oxygen species. dksa-dependent transcriptional control promotes antinitrosative and antioxidative defenses that contribute to salmonella pathogenesis. the specific adaptive changes mediated by dksa in response to reactive specie ...201627065993
expression and secretion pattern of fljb of salmonella enterica serovar typhi in different culture conditions. 201627057676
the typhoid toxin promotes host survival and the establishment of a persistent asymptomatic infection.bacterial genotoxins, produced by several gram-negative bacteria, induce dna damage in the target cells. while the responses induced in the host cells have been extensively studied in vitro, the role of these effectors during the course of infection remains poorly characterized. to address this issue, we assessed the effects of the salmonella enterica genotoxin, known as typhoid toxin, in in vivo models of murine infection. immunocompetent mice were infected with isogenic s. enterica, serovar ty ...201627055274
fluorescence-based thermal shift data on multidrug regulator acrr from salmonella enterica subsp. entrica serovar typhimurium str. lt2.the fluorescence-based thermal shift (fts) data presented here include table s1 and fig. s1, and are supplemental to our original research article describing detailed structural, fts, and fluorescence polarization analyses of the salmonella enterica subsp. entrica serovar typhimurium str. lt2 multidrug transcriptional regulator acrr (stacrr) (doi:10.1016/j.jsb.2016.01.008) (manjasetty et al., 2015 [1]). table s1 contains chemical formulas, a chemical abstracts service (cas) registry number (cas ...201627054155
evaluation the antibacterial effects of echinophora platyloba extracts against some salmonella species.salmonellosis, which is caused by nontyphoid salmonella bacteria, is one of the most common foodborne diseases, and it causes gastrointestinal infections worldwide, most of which are limited gastroenteritis that requires antimicrobial treatment. the aim of this study was to investigate the effects of echinophora platyloba extract on inhibiting the growth of salmonella typhi, salmonella enteritidis, and salmonella choleraesuis.201627054002
genetic relatedness of salmonella serovars isolated from catfish (clarias gariepinus) and tilapia (tilapia mossambica) obtained from wet markets and ponds in penang, malaysia.a total of 43 salmonella enterica isolates belonging to different serovars (salmonella albany, salmonella agona, salmonella corvallis, salmonella stanley, salmonella typhimurium, salmonella mikawasima, and salmonella bovismorbificans) were isolated from catfish (clarias gariepinus) and tilapia (tilapia mossambica) obtained from nine wet markets and eight ponds in penang, malaysia. thirteen, 19, and 11 isolates were isolated from 9 of 32 catfish, 14 of 32 tilapia, and 11 of 44 water samples, resp ...201627052872
irradiance and temperature influence the bactericidal effect of 460-nanometer light-emitting diodes on salmonella in orange juice.blue light-emitting diodes (leds) have been known to produce an antibacterial effect on various pathogenic bacteria. to extend this application to foods, blue 460-nm leds were evaluated for their antibacterial effect on salmonella in orange juice. a cocktail of salmonella enterica serovars gaminara, montevideo, newport, typhimurium, and saintpaul was inoculated into pasteurized orange juice and illuminated with 460-nm leds at irradiances of 92, 147.7, and 254.7 mw/cm(2) and temperatures of 4, 12 ...201627052858
diagnostic accuracy of rectoanal mucosal swab of feedlot cattle for detection and enumeration of salmonella enterica.cattle are noted carriers of the foodborne pathogen salmonella enterica. the perceived need to decrease the potential human health risk posed by excretion of this pathogen has resulted in numerous studies examining the factors that influence salmonella shedding in cattle. fecal grab (fg) samples have been the predominant method used to identify cattle colonized or infected with salmonella; however, fg sampling can be impractical in certain situations, and rectoanal mucosal swabs (rams) are a mor ...201627052855
evaluation of corn oil as an additive in the pre-enrichment step to increase recovery of salmonella enterica from oregano.phenolic compounds associated with essential oils of spices and herbs possess a variety of antioxidant and antimicrobial properties that interfere with salmonella detection from fresh and dried products. finding a compound to neutralize the effect of these antimicrobial compounds, while allowing salmonella growth during pre-enrichment, is a crucial step in both traditional pathogen isolation and molecular detection from these foods. this study evaluated the effectiveness of corn oil as a compone ...201627052719
prevalence and characterization of multi-drug resistant salmonella enterica serovar gallinarum biovar pullorum and gallinarum from chicken.salmonella is an important zoonotic pathogen responsible for animal and human diseases. the aim of the present study was to determine the prevalence and stereotyping of salmonella isolates isolated from apparently healthy poultry. furthermore, the clonal relatedness among the isolated salmonella serovars was assessed.201627051187
prevalence and epidemiology of salmonella enterica serovar gallinarum from poultry in some parts of haryana, india.the present study was investigated to ascertain the epidemiological status of fowl typhoid (ft) in broilers in some parts of haryana during january 2011 to december 2013.201527047033
[laboratory surveillance of salmonella enterica from human clinical cases in colombia 2005-2011].salmonella is an enteropathogen acquired through contaminated food or water. in colombia, salmonella spp. is included in the national surveillance of acute diarrhoeal diseases and typhoid fever initiated in 1997. this report shows the phenotype and genotype results obtained from 2005 to 2011.201627038678
nontyphoidal salmonella disease: current status of vaccine research and development.among more than 2500 nontyphoidal salmonella enterica (nts) serovars, s. enterica serovar typhimurium and s. enterica serovar enteritidis account for approximately fifty percent of all human isolates of nts reported globally. the global incidence of nts gastroenteritis in 2010 was estimated to be 93 million cases, approximately 80 million of which were contracted via food-borne transmission. it is estimated that 155,000 deaths resulted from nts in 2010. nts also causes severe, extra-intestinal, ...201627032517
conserved transmembrane glycine residues in the shigella flexneri polysaccharide co-polymerase protein wzzb influence protein-protein interactions.the o antigen (oag) component of lipopolysaccharides (lps) is crucial for virulence and oag chain-length regulation is controlled by the polysaccharide co-polymerase class 1 (pcp1) proteins. crystal structure analyses indicate that structural conservation among pcp1 proteins is highly maintained, however the mechanism of oag modal-chain-length control remains to be fully elucidated. shigella flexneri pcp1 protein wzzbsf confers a modal-chain length of 10-17 oag repeat units (rus), whereas the sa ...201627028755
antimicrobial susceptibility and plasmid replicon typing of salmonella enterica serovar kentucky isolates recovered from broilers.salmonella kentucky has become the predominant serovar recovered from broilers slaughtered in the united states, and the prevalence of antimicrobial resistance (amr) has increased dramatically in this serovar. relationships between amr, genotype, and plasmid replicon types were characterized for 600 salmonella kentucky isolates recovered from chicken carcasses from 2004 to 2013. pulsed-field gel electrophoresis cluster analysis revealed 112 unique types sharing 79% similarity. over half of the i ...201627028167
draft whole-genome sequences of salmonella enterica subsp. enterica serovars enteritidis, veneziana, and salford, isolated from herbs.salmonellais a foodborne pathogen found in a wide variety of sources. here, we report draft genome sequences of threesalmonella entericasubsp.entericaserovars found in herbs: enteritidis, veneziana, and salford, with the latter two being extremely rare in california.201627013038
l-2,3-diaminopropionate generates diverse metabolic stresses in salmonella enterica.unchecked amino acid accumulation in living cells has the potential to cause stress by disrupting normal metabolic processes. thus, many organisms have evolved degradation strategies that prevent endogenous accumulation of amino acids. l-2,3-diaminopropionate (dap) is a non-protein amino acid produced in nature where it serves as a precursor to siderophores, neurotoxins and antibiotics. dap accumulation in salmonella enterica was previously shown to inhibit growth by unknown mechanisms. the prod ...201627010356
emergence and diversity of salmonella enterica serovar indiana isolates with concurrent resistance to ciprofloxacin and cefotaxime from patients and food-producing animals in china.salmonellosis is a major global foodborne infection, and strains that are resistant to a great variety of antibiotics have become a major public health concern. the aim of this study was to identify genes conferring resistance to fluoroquinolones and extended-spectrum β-lactams in nontyphoidal salmonella (nts) from patients and food-producing animals in china. in total, 133 and 21 nts isolates from animals and humans, respectively, exhibiting concurrent resistance to ciprofloxacin and cefotaxime ...201627001808
whole genome sequencing provides insights into the genetic determinants of invasiveness in salmonella dublin.salmonella enterica subsp. enterica serovar dublin (s. dublin) is one of the non-typhoidal salmonella (nts); however, a relatively high proportion of human infections are associated with invasive disease. we applied whole genome sequencing to representative invasive and non-invasive clinical isolates of s. dublin to determine the genomic variations among them and to investigate the underlying genetic determinants associated with invasiveness in s. dublin. although no particular genomic variation ...201626996313
broilers with low serum mannose-binding lectin show increased fecal shedding of salmonella enterica serovar montevideo.mannose-binding lectin (mbl) is a key molecule in innate immunity. mbl binds to carbohydrates on the surface of pathogens, initiating the complement system via the lectin-dependent pathway or facilitates opsonophagocytosis. in vivo studies using inbred chicken lines differing in mbl serum concentration indicate that chicken mbl affects salmonella resistance; further studies are imperative in conventional broiler chickens. in this study 104 conventional day-old chickens (offspring from a cross be ...201626994208
complete genome and methylome sequences of salmonella enterica subsp. enterica serovar panama (atcc 7378) and salmonella enterica subsp. enterica serovar sloterdijk (atcc 15791).salmonella enterica spp. are pathogenic bacteria commonly associated with food-borne outbreaks in human and animals. salmonella enterica spp. are characterized into more than 2,500 different serotypes, which makes epidemiological surveillance and outbreak control more difficult. in this report, we announce the first complete genome and methylome sequences from two salmonella type strains associated with food-borne outbreaks, salmonella enterica subsp. enterica serovar panama (atcc 7378) and salm ...201626988049
[fluorescent and magnetic relaxation switch immunosensor for the detecting foodborne pathogen salmonella enterica in water samples].fluoroimmunoassay based on quantum dots (qds) and magnetic relaxation switch (mrs) immunoassay based on superparamagnetic nanoparticles (smn) were constructed to detect salmonella enterica (s. enterica) in water samples. in fluoroimmunoassay, magnetic beads was conjugated with s. enterica capture antibody (mb-ab2) to enrich s. enterica from sample solution, then the qds was conjugated with the s. enterica detection antibody (qds-ab1) to detect s. enterica based on sandwich immunoassay format. an ...201526978918
phenotypic and genotypic diversity of salmonella in finishing swine.salmonella enterica (nontyphoidal) is one of the major causes of foodborne diseases in the united states and worldwide. molecular typing methods are significant tools used to better understand the transmission and ecology of salmonella in order to implement pre-harvest control measures. the objectives of this study were to describe the salmonella genotypes, the distribution of isolate subtypes from different ecological niches (i.e., barn environment, nursery, and individual pigs) and their evolu ...201626977814
global mlst of salmonella typhi revisited in post-genomic era: genetic conservation, population structure, and comparative genomics of rare sequence types.typhoid fever, caused by salmonella enterica serovar typhi, remains an important public health burden in southeast asia and other endemic countries. various genotyping methods have been applied to study the genetic variations of this human-restricted pathogen. multilocus sequence typing (mlst) is one of the widely accepted methods, and recently, there is a growing interest in the re-application of mlst in the post-genomic era. in this study, we provide the global mlst distribution of s. typhi ut ...201626973639
presence of plasmid-mediated quinolone resistance determinants and mutations in gyrase and topoisomerase in salmonella enterica isolates with resistance and reduced susceptibility to ciprofloxacin.in recent decades, the emergence and spread of resistance to nalidixic acid are usually associated with reduced susceptibility to ciprofloxacin among salmonella serotypes. the aims of this study were to investigate the mechanisms associated with resistance to fluoroquinolone and the clonal relatedness of salmonella strains isolated from human and nonhuman origins, in a 5-year period in são paulo, brazil. antimicrobial susceptibility testing for salmonella isolates was performed. pcr and dna sequ ...201626971183
development of a simple, peripheral-blood-based lateral-flow dipstick assay for accurate detection of patients with enteric fever.enteric fever is a systemic infection caused by typhoidal strains of salmonella enterica and is a significant cause of mortality and morbidity in many parts of the world, especially in resource-limited areas. unfortunately, currently available diagnostic tests for enteric fever lack sensitivity and/or specificity. no true clinically practical gold standard for diagnosing patients with enteric fever exists. unfortunately, microbiologic culturing of blood is only 30 to 70% sensitive although 100% ...201626961857
salmonella typhimurium undergoes distinct genetic adaption during chronic infections of mice.typhoid fever caused by salmonella enterica serovar typhi (s. typhi) is a severe systemic human disease and endemic in regions of the world with poor drinking water quality and sewage treatment facilities. a significant number of patients become asymptomatic life-long carriers of s. typhi and serve as the reservoir for the disease. the specific mechanisms and adaptive strategies enabling s. typhi to survive inside the host for extended periods are incompletely understood. yet, elucidation of the ...201626955808
draft genome sequence of a salmonella enterica subsp. enterica serovar gallinarum bv. gallinarum isolate associated with fowl typhoid outbreaks in brazil.salmonella enterica subsp. enterica serovar gallinarum bv. gallinarum strains are bird pathogens causing fowl typhoid (ft). isolate br_rs12 was obtained from a poultry flock with ft in 2014. the sequencing of this genome will enable to track the origin of the recent outbreaks in brazil.201626950322
assessing the growth of escherichia coli o157:h7 and salmonella in spinach, lettuce, parsley and chard extracts at different storage temperatures.the objective of this work was to study the growth potential of escherichia coli o157:h7 and salmonella spp. in leafy vegetable extracts at different temperature conditions.201626950043
effective photosensitization-based inactivation of gram (-) food pathogens and molds using the chlorophyllin-chitosan complex: towards photoactive edible coatings to preserve strawberries.this study is focused on the novel approaches to enhance the inactivation of the gram (-) food pathogen salmonella enterica and harmful molds in vitro and on the surface of strawberries using the chlorophyllin-chitosan complex. salmonella enterica (∼1 × 10(7) cfu ml(-1)) was incubated with chlorophyllin 1.5 × 10(-5) m (chl, food additive), chitosan 0.1% (chs, food supplement) or the chlorophyllin-chitosan complex (1.5 × 10(-5) m chl-0.1% chs) and illuminated with visible light (λ = 405 nm, light ...201626947225
colonization of internal organs by salmonella enteritidis in experimentally infected laying hens housed in enriched colony cages at different stocking densities.epidemiologic analyses have linked the frequency of human infections with salmonella enterica subspecies enterica serovar enteritidis to the consumption of contaminated eggs and thus to the prevalence of this pathogen in commercial egg-laying flocks. contamination of the edible contents of eggs by salmonella enteritidis is a consequence of the colonization of reproductive tissues in systemically infected hens. the animal welfare implications of laying hen housing systems have been widely debated ...201626944976
differential antibacterial response of chicken granulosa cells to invasion by salmonella serovars.in the united states, salmonella enterica ser. enteritidis (se) is among the leading bacterial cause of foodborne illness via consumption of raw or undercooked eggs. the top salmonella serovars implicated in u.s. foodborne outbreaks associated with chicken consumption include se, typhimurium (st), heidelberg (sh), montevideo, mbandka, braenderup, and newport. while enforcement actions target the eradication of se from layer hens, there is a growing concern that other serovars could occupy this n ...201626944965
development of a loop mediated isothermal amplification (lamp) - surface enhanced raman spectroscopy (sers) assay for the detection of salmonella enterica serotype enteritidis.as a major foodborne pathogen, salmonella enterica serotype enteritidis is increasingly rising as a global health concern. here, we developed an integrated assay that combines loop mediated isothermal amplification (lamp) and surface enhanced raman spectroscopy (sers) for dna detection of s. enteritidis using specifically designed raman active au-nanoprobes. the target dna was amplified by lamp and then labeled with au-nanoprobes comprised of gold nanoparticle-modified with specific cy5/dna prob ...201626941845
study of salmonella typhimurium infection in laying hens.members of salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. in australia, salmonella typhimurium is frequently involved in egg and egg product related foodborne illness and salmonella mbandaka has also been found to be a contaminant of the layer farm environment. the ability possessed by salmonella enteritidis to colonize reproductive organs and contaminate developing eggs has been well-described. however, there are few studies ...201626941727
draft whole-genome sequences of 25 salmonella enterica strains representing 24 serovars.we report the draft genome sequences of 25 salmonella enterica strains representing 24 different serotypes, many of which were not available in public repositories during our selection process. these draft genomes will provide useful reference for the genetic variation between serotypes and aid in the development of molecular typing tools.201626941156
new insights about excisable pathogenicity islands in salmonella and their contribution to virulence.pathogenicity islands (pais) are regions of the chromosome of pathogenic bacteria that harbor virulence genes, which were probably acquired by lateral gene transfer. several pais can excise from the bacterial chromosome by site-specific recombination and in this review have been denominated "excisable pais". here, the characteristic of some of the excisable pais from salmonella enterica and the possible role and impact of the excision process on bacterial virulence is discussed. understanding th ...201626939722
genome-scale screening and validation of targets for identification of salmonella enterica and serovar prediction.salmonella enterica is the most common foodborne pathogen worldwide, with 2,500 recognized serovars. detection of s. enterica and its classification into serovars are essential for food safety surveillance and clinical diagnosis. the pcr method is useful for these applications because of its rapidity and high accuracy. we obtained 412 candidate detection targets for s. enterica using a comparative genomics mining approach. gene ontology (go) functional enrichment analysis of these candidate targ ...201626939647
strain-specific survival of salmonella enterica in peanut oil, peanut shell, and chia seeds.in north america, outbreaks of salmonella have been linked to low-water activity (aw) foods, such as nuts and seeds. these outbreaks have implicated an assortment of salmonella serotypes. some salmonella serotypes (e.g., enteritidis and typhimurium) cause high proportions of salmonellosis. nevertheless, there has recently been an emergence of uncommon salmonella serotypes and strains (e.g., tennessee, hartford, and thompson) in low-aw foods. the aim of this study was to evaluate the survival cha ...201626939645
autoregulation of the tufb operon in salmonella.in salmonella enterica and related species, translation elongation factor ef-tu is encoded by two widely separated but near-identical genes, tufa and tufb. two thirds of ef-tu is expressed from tufa with the remaining one third coming from tufb. inactivation of tufa is partly compensated by a doubling in the amount of ef-tub but the mechanism of this up-regulation is unknown. by experimental evolution selecting for improved growth rate in a strain with an inactive tufa we selected six different ...201626934594
prevalence of salmonella excretion in stool: a community survey in 2 sites, guinea-bissau and senegal.chronic and convalescent carriers play an important role in the transmission and endemicity of many communicable diseases. a high incidence of salmonella enterica serovar typhi and invasive nontyphoidal salmonella (nts) infection has been reported in parts of sub-saharan africa, yet the prevalence of salmonella excretion in the general population is unknown.201626933022
a multicountry molecular analysis of salmonella enterica serovar typhi with reduced susceptibility to ciprofloxacin in sub-saharan africa.salmonella enterica serovar typhi is a predominant cause of bloodstream infections in sub-saharan africa (ssa). increasing numbers of s. typhi with resistance to ciprofloxacin have been reported from different parts of the world. however, data from ssa are limited. in this study, we aimed to measure the ciprofloxacin susceptibility of s. typhi isolated from patients with febrile illness in ssa.201626933020
challenges and opportunities for typhoid fever control: a call for coordinated action.the burden of enteric fever caused by salmonella enterica serovars typhi and paratyphi is substantial and has high impact in toddlers and young children. this burden is relatively well documented in asia, and this supplement provides new data on the substantial burden in several sub-saharan african countries. challenges in standardized surveillance and imperfect diagnostic tools have resulted in patchy local disease data, which are not well acknowledged or integrated into local country evidence ...201626933019
diagnosing salmonella enterica serovar typhi infections by polymerase chain reaction using edta blood samples of febrile patients from burkina faso.globally, there are an estimated 22 million cases of salmonella enterica serovar typhi infection each year. however, this figure is likely to be an underestimate due to the low sensitivity of blood culture in s. typhi diagnosis. the aim of this study was to diagnose s. typhi by conventional polymerase chain reaction (pcr) using patient's blood preserved with ethylenediamine tetraacetic acid (edta).201626933018
variations of invasive salmonella infections by population size in asante akim north municipal, ghana.the typhoid fever surveillance in africa program (tsap) estimated adjusted incidence rates (irs) for salmonella enterica serovar typhi and invasive nontyphoidal s. enterica serovars (ints) of >100 cases per 100 000 person-years of observation (pyo) for children aged <15 years in asante akim north municipal (aan), ghana, between march 2010 and may 2012. we analyzed how much these rates differed between rural and urban settings.201626933015
what have we learned from the typhoid fever surveillance in africa program?the typhoid fever surveillance in africa program (tsap) was established in 2009 to fill the data void concerning invasive salmonella disease in sub-saharan africa, and to specifically estimate the burden of bloodstream infections caused by the key pathogen, salmonella enterica serovar typhi. tsap has achieved this ambitious target, finding high incidences of typhoid fever in both rural and urban populations in several countries in sub-saharan africa. the results of tsap will undoubtedly dictate ...201626933014
unraveling the effects of static magnetic field stress on cytosolic proteins of salmonella by using a proteomic approach.the present study investigated the adaptation of salmonella enterica subsp. enterica serovar hadar to static magnetic field (smf) exposure (200 mt, 9 h). the proteomic analysis provides an overview of potentially important cytosolic proteins that salmonella needs to regulate to survive and adapt to magnetic stress. via 2-dimensional electrophoresis and liquid chromatography tandem mass spectrometry, we compared cytosolic proteomes before and after exposure to magnetic field. a total of 35 protei ...201626928316
mechanisms of resistance to linalool in salmonella senftenberg and their role in survival on basil.fresh produce contaminated with human pathogens raises vital and ecological questions about bacterial survival strategies. such occurrence was basil harboring salmonella enterica serovar senftenberg that caused an outbreak in 2007. this host was unanticipated due to its production of antibacterial substances, including linalool. we show that linalool perforates bacterial membranes, resulting in increased permeability and leakage of vital molecules. it also inhibits cell motility and causes bacte ...201626914987
haloarchaeal gas vesicle nanoparticles displaying salmonella antigens as a novel approach to vaccine development.a safe, effective, and inexpensive vaccine against typhoid and other salmonella diseases is urgently needed. in order to address this need, we are developing a novel vaccine platform employing buoyant, self-adjuvanting gas vesicle nanoparticles (gvnps) from the halophilic archaeon halobacterium sp. nrc-1, bioengineered to display highly conserved salmonella enterica antigens. as the initial antigen for testing, we selected sopb, a secreted inosine phosphate effector protein injected by pathogeni ...201726900411
the o-antigen mediates differential survival of salmonella against communities of natural predators.antigenically-distinct members of bacterial species can be differentially distributed in the environment. predators known to consume antigenically-distinct prey with different efficiencies are also differentially distributed. here we show that antigenically-distinct, but otherwise isogenic and physiologically indistinct, strains of salmonella enterica show differential survival in natural soil, sediment and intestinal environments where they would face a community of predators. decline in overal ...201626888189
characterization of quinolone resistance in salmonella spp. isolates from food products and human samples in brazil.non-typhoidal salmonellosis is an important zoonotic disease caused by salmonella enterica. the aim of this study was to investigate the prevalence of plasmid-mediated quinolone resistance in salmonella spp. and its association with fluoroquinolone susceptibility in brazil. a total of 129 nts isolates (samples from human origin, food from animal origin, environmental, and animal) grouped as from animal (n=62) and human (n=67) food were evaluated between 2009 and 2013. these isolates were investi ...201626887245
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