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simultaneous detection of multifood-borne pathogenic bacteria based on functionalized quantum dots coupled with immunomagnetic separation in food samples.this paper reports a method that simultaneously detects three food-borne pathogenic bacteria, salmonella typhimurium, shigella flexneri, and escherichia coli o157:h7, via an approach that combines magnetic microparticles for the enrichment and antibody-conjugated semiconductor quantum dots (qds) as fluorescence markers. using the water-in-oil reverse microemulsions method, the gamma-fe(2)o(3) magnetic nanoparticles were coated with silica to empower the particles with high dispersibility and bro ...200919154162
overexpression, purification, characterization and preliminary crystallographic study of phosphoglycolate phosphatase from shigella flexneri 2a strain 301.phosphoglycolate phosphatase has a salvage function in the metabolism of the 2-phosphoglycolate formed during bacterial dna repair. in order to better understand its dimerization behaviour, the influence of metal ions on its activity and its catalytic mechanism at the molecular level, recombinant phosphoglycolate phosphatase from shigella flexneri was overexpressed, purified, characterized and crystallized by the hanging-drop vapour-diffusion method at 291 k using polyethylene glycol 3500 as a p ...200919153451
functions and pathologies of bip and its interaction partners.the endoplasmic reticulum (er) is involved in a variety of essential and interconnected processes in human cells, including protein biogenesis, signal transduction, and calcium homeostasis. the central player in all these processes is the er-lumenal polypeptide chain binding protein bip that acts as a molecular chaperone. bip belongs to the heat shock protein 70 (hsp70) family and crucially depends on a number of interaction partners, including co-chaperones, nucleotide exchange factors, and sig ...200919151922
[evaluation of laboratory diagnosis of the first norovirus outbreak in turkey in 2008].norovirus (nov) is one of the most prominent agents of gastroenteritis and water/food-borne outbreaks affecting all of the age groups in the world. as the identification of the etiologic agent is important during gastroenteritis outbreaks, it is recommended to combine two different methods for rapid and reliable laboratory diagnosis of nov. although nov outbreaks have been observed in many different countries of the world, there was no report on "nov outbreak" in turkey till 2008 due to the abse ...200819149082
[typing of shigella sonnei strains isolated in some provinces of turkey using antimicrobial resistance and pulsed field gel electrophoresis methods].shigella species may lead to large epidemics owing to their low infective doses and frequent transmission from person to person with high secondary attack rates. shigella sonnei is one of the most prevalent causative agent of infectious gastroenteritis in developing and developed countries and it is the most frequently reported shigella serotype from turkey in recent years. the aim of this study was to determine the types of s. sonnei strains isolated in different provinces of turkey [in marmara ...200819149077
etiology of acute gastroenteritis in three sentinel general practices, austria 2007.we studied the etiology of acute gastroenteritis in a village with a total population of approximately 6,000. this is the first study in austria that has investigated a broad range of pathogens recovered from an unselected population of patients who had consulted general practitioners because of gastroenteritis.200919148576
septins regulate bacterial entry into host cells.septins are conserved gtpases that form filaments and are required in many organisms for several processes including cytokinesis. we previously identified sept9 associated with phagosomes containing latex beads coated with the listeria surface protein inlb.200919145258
improvement in detection of enterotoxigenic escherichia coli in patients with travelers' diarrhea by increasing the number of e. coli colonies tested.no cause of one-third of travelers' diarrhea (td) cases can be detected despite microbiologic assessment. we propose that these pathogen-negative td cases include undetected enterotoxigenic escherichia coli (etec). as a standard in diagnostic microbiology, samples of five e. coli colonies were tested to detect etec from stool cultures. we compared the sensitivities and the number of etec detected by 20 colonies with those of 5, 10, and 15 colonies. the percent detection of etec with five e. coli ...200919141833
giardia duodenalis assemblages associated with diarrhea in children in south india identified by pcr-rflp.giardial diarrhea in a birth cohort of 452 children in an urban slum in south india was characterized. of the 155 episodes that occurred in 99 children, 73% were acute diarrhea. children with better educated mothers and a toilet at home had lower odds of acquiring giardial diarrhea, whereas low socioeconomic status and drinking municipal water were associated with greater risk. children with co-infections tended to have a slightly longer duration of diarrhea (p = 0.061) and showed significantly ...200919141832
rapid emergence of third generation cephalosporin resistant shigella spp. in southern vietnam. 200919141753
in silico comparison of simple sequence repeats in high nucleotides-rich genomes of microorganism.this study determined the distribution of a specific group of simple sequence repeats (ssrs), in genome sequences of 7 chromosomes (shigella flexneri 2a str 301 and 2457 t, shigella sonnei, e. coli k12, m. tuberculosis, m. leprae and s. saprophytycus) have downloaded from the genbank database for identifying abundance, distribution and composition of ssrs. the data obtained in the present study show that: (i) tandem repeats are widely distributed throughout the genomes. (ii) ssrs are differentia ...200819137845
trends in antimicrobial resistance of fecal shigella and salmonella isolates in tehran, iran.the resistance of bacteria to commonly prescribed antibiotics is increasing both in developing as well as developed countries. resistance has emerged even to newer, more potent antimicrobial agents. the present study was therefore undertaken to report resistance rates to antimicrobial agents in 2487 stool culture isolates in a tertiary care hospital between 1996 and 2000 and 2001 and 2005.200919136781
safety and immunogenicity of sc599, an oral live attenuated shigella dysenteriae type-1 vaccine in healthy volunteers: results of a phase 2, randomized, double-blind placebo-controlled trial.sc599 vaccine is a live shigella dysenteriae 1 strain attenuated by deletion of invasion [icsa], iron chelation [ent, fep] and shiga toxin a subunit [stxa] genes. in a preliminary phase 1 single dose prospective study, we showed that sc599 vaccine was well tolerated, and the maximum tolerable dose was greater than 10(8) cfu [sadorge c, ndiaye a, beveridge n, frazer s, giemza r, jolly n, et al. phase 1 clinical trial of live attenuated shigella dysenteriae type-1 deltaicsa deltaent deltafep delta ...200919135496
frequency of isolation of various subtypes and antimicrobial resistance of shigella from urban slums of karachi, pakistan.shigellosis remains a major public health problem in developing countries. antimicrobial resistance has complicated the empirical treatment. knowledge of serotypes is crucial in vaccine development, as cross-protection between various serotypes is limited. therefore we conducted a prospective study to determine the frequency of isolation of shigella serotypes and antimicrobial resistance.200919135399
outbreaks of shigella sonnei infections in denmark and australia linked to consumption of imported raw baby corn.we investigated an outbreak of shigella sonnei infections in denmark and australia associated with imported baby corn from one packing shed in thailand. we reviewed nationwide surveillance and undertook case finding, food trace-back and microbiological investigation of human, food and environmental samples. a recall of baby corn and sugar snaps was based on descriptive epidemiological evidence. in denmark, we undertook a retrospective cohort study in one workplace. in total, 215 cases were labor ...200919134229
genetics and environmental regulation of shigella iron transport systems.shigella spp. have transport systems for both ferric and ferrous iron. the iron can be taken up as free iron or complexed to a variety of carriers. all shigella species have both the feo and sit systems for acquisition of ferrous iron, and all have at least one siderophore-mediated system for transport of ferric iron. several of the transport systems, including sit, iuc/iuta (aerobactin synthesis and transport), fec (ferric di-citrate uptake), and shu (heme transport) are encoded within pathogen ...200919130265
bacterial particle endocytosis by epithelial cells is selective and enhanced by tumor necrosis factor receptor ligands.bacterial pathogens use virulence strategies to invade epithelial barriers, but active processes of epithelial cells may also contribute to the endocytosis of microbial particles. to focus on the latter, we studied the uptake of fixed and fluorescently labeled bacterial particles in intestinal and bronchoepithelial cell cultures and found it to be enhanced in caco-2bbe and nci-h292 cells after treatment with tumor necrosis factor alpha and an agonist antibody against the lymphotoxin beta recepto ...200919129472
antifungal and antibacterial activities of mexican tarragon (tagetes lucida).mexican tarragon (tagetes lucida cv. asteraceae: campanulatae) is an important, nutritious plant and an effective herbal medicine. seven coumarins, 7,8-dihydroxycoumarin (4), umbelliferone (7-hydroxycoumarin) (5), scoparone (6,7-dimethoxycoumarin) (7), esculetin (6,7-dihydroxycoumarin) (11), 6-hydroxy-7-methoxycoumarin (12), herniarin (7-methoxycoumarin) (13), and scopoletin (6-methoxy-7-hydroxycoumarin) (14), and three flavonoids, patuletin (18), quercetin (19), and quercetagetin (20), were iso ...200619127719
oral immunization: an update.oral immunization with vaccines against intestinal infectious diseases has been extensively explored for several decades. despite the immunologic and economic rationale behind oral immunization, only a few mucosal vaccines are available for the prevention of mucosal infections. here, we summarize the current status of such vaccines, with a focus on intestinal infectious diseases, describe alternative approaches, and analyze advantages and difficulties encountered with a broad implementation of t ...200819122521
diagnosis and prevalence of enteropathogenic bacteria in children less than 5 years of age with acute diarrhea in tehran children's hospitals.acute diarrhea disease is the second cause of death among all infectious diseases in children younger than 5 years of age worldwide. the aim of this study was to employ a combination of biochemical, microbiological and molecular diagnostic techniques to investigate the stools of iranian children with acute diarrhea for bacterial enteropathogens.200919117609
antimicrobial activity of prulifloxacin tested against a worldwide collection of gastroenteritis-producing pathogens, including those causing traveler's diarrhea.prulifloxacin, the prodrug of ulifloxacin (active component), is a newer fluoroquinolone with broad activity against enteric and nonenteric gram-negative bacilli. ulifloxacin and other oral comparator agents were tested for activity against 582 gastroenteritis strains from global surveillance studies. ulifloxacin was highly active against escherichia coli, salmonella spp., shigella spp., yersinia spp., vibrio spp., aeromonas spp., and plesiomonas spp. (mic(50)s and mic(90)s, <or=0.03 microg/ml a ...200919114678
extensive antibody cross-reactivity among infectious gram-negative bacteria revealed by proteome microarray analysis.antibodies provide a sensitive indicator of proteins displayed by bacteria during sepsis. because signals produced by infection are naturally amplified during the antibody response, host immunity can be used to identify biomarkers for proteins that are present at levels currently below detectable limits. we developed a microarray comprising approximately 70% of the 4066 proteins contained within the yersinia pestis proteome to identify antibody biomarkers distinguishing plague from infections ca ...200919112181
water-related diseases outbreaks reported in italy.water related disease outbreak (wrdo) statistics in italy from 1998 to 2005 have been discussed in this paper. the true incidence of wrdo is not reflected in the national surveillance system (nss), although this study has provided information on pathogens associated to different water sources, incidence in regions and inadequacy of regulations. 192 outbreaks and 2546 cases of wrd were reported to the nss, an average of 318 cases per year. cases were associated to shellfish (58.79%), drinking wat ...200819108563
[detection and identification of seven clinical common pathogenic bacteria by oligonucleotide microarray].using 16s rdna and 23s rdna genes as the target sequences to develop a system based on oligonucleotide microarray and to detect the seven clinical pathogenic bacteria, commonly seen.200819103121
analysis of plasmid genes by phylogenetic profiling and visualization of homology relationships using blast2network.phylogenetic methods are well-established bioinformatic tools for sequence analysis, allowing to describe the non-independencies of sequences because of their common ancestor. however, the evolutionary profiles of bacterial genes are often complicated by hidden paralogy and extensive and/or (multiple) horizontal gene transfer (hgt) events which make bifurcating trees often inappropriate. in this context, plasmid sequences are paradigms of network-like relationships characterizing the evolution o ...200819099604
genomic analysis of bacteriophage epsilon 34 of salmonella enterica serovar anatum (15+).the presence of prophages has been an important variable in genetic exchange and divergence in most bacteria. this study reports the determination of the genomic sequence of salmonella phage epsilon 34, a temperate bacteriophage that was important in the early study of prophages that modify their hosts' cell surface and is of a type (p22-like) that is common in salmonella genomes.200819091116
fungal and bacterial killing by neutrophils.neutrophils are professional phagocytes of the innate immune system that are essential to control bacterial and fungal infections. these cells engulf and kill invading microbes. additionally, activated neutrophils are able to release neutrophil extracellular traps (nets). these fibers consist of chromatin decorated with antimicrobial proteins to trap and kill microbes. appropriate quantitative methods are required to understand the nature of interactions of neutrophils with pathogens. here we pr ...200919089391
[structures of o-polysaccharides from two shigella dysenteriae type 8 strains].the structure of the o-polysaccharide (o-antigen) from shigella dysenteriae type 8 bacteria (strain 599) was corrected using modern nmr techniques (structure 1). the revisions concerned the position of the glc residue (in the main, but not the side, chain), the site of its substitution, and the configuration of the o-glycoside linkage of the glcnac residue. the s. dysenteriae type 8 bacterium (strain g1221), the second investigated representative, was found to produce another structural variant ...200819088755
shigella from humans in thailand during 1993 to 2006: spatial-time trends in species and serotype distribution.in thailand during 1993-2006, a total of 9063 shigella isolates from different medical centers were serotyped and trends over time and spatial clustering analyzed. of 3583 cases with age information, 1315 (37%) cases were from children between 0 and 4 years and 684 (19%) from children between 5 and 8 years. most infections were recorded during 1993-1994 (> 1500 per year), decreasing to < 200 in 2006. the relative species distribution also changed. during 1993-1994, shigella flexneri accounted fo ...200819086804
molecular detection of all 34 distinct o-antigen forms of shigella.shigella is the cause of shigellosis or bacillary dysentery, the occurrence of which is estimated to be 165 million cases per year worldwide, resulting in 1.1 million deaths. rapid and reliable assays for detecting and identifying shigella in food, environmental and clinical samples are therefore necessary. shigella species are traditionally identified by their o antigens. this study developed a dna microarray targeting o-serotype-specific genes to detect all 34 distinct o-antigen forms of shige ...200919074655
the prevalence and antibiotic resistance of shigella sp. recovered from patients admitted to bouali hospital, tehran, iran during 1999-2001.the present study was conducted to determine the prevalence of serotypes and antibiotic resistance in shigella spp. isolated from patients admitted to bouali hospital, tehran, iran during 1999 to 2001. all cases of shigellosis that were diagnosed according to their clinical pictures and microbial cultures were included in current study. patients' age ranged from 12 to 89 years. overall, 52 patients (56%) and 41(44%) were males and female, respectively. from a total of 90 shigella isolates, 40 st ...200719070104
prevalence of shigella serogroups and their antimicrobial resistance patterns in southern trinidad.the serogroup distribution and antimicrobial susceptibility patterns of shigella isolates obtained from stool specimens of persons with acute diarrhoea in community-based studies from southern trinidad during 1997-2006 were reviewed. of the 5,187 stool specimens, 392 (8%) were positive for shigella organisms. from these 392 isolates, 88.8% were recovered from children aged >0-10 year(s). shigella sonnei was the most frequently-isolated serogroup (75%), followed by s. flexneri (19%), s. boydii (4 ...200819069625
prevalence of bacteria and intestinal parasites among food-handlers in gondar town, northwest ethiopia.food-handlers with poor personal hygiene working in food-service establishments could be potential sources of infection due to pathogenic organisms. the study was undertaken to determine the prevalence of bacteria and intestinal parasites among 127 food-handlers working in the cafeterias of the university of gondar and the gondar teachers training college, gondar, ethiopia. fingernail contents of both the hands and stool specimens were collected from all the 127 food-handlers. the samples were e ...200819069624
increased isolation and characterization of shigella sonnei obtained from hospitalized children in tehran, iran.shigella flexneri has been the most frequent cause of shigellosis in children in iran. to evaluate the changes in frequency of serogroups, 302 shigella species were isolated in 2003 from hospitalized children, aged less than 12 years, with acute diarrhoea in tehran, iran. the number of collected s. sonnei, s. flexneri, s. boydii, and s. dysenteriae isolates was 178 (58.9%), 110 (37.4%), 10 (3.3%), and 4 (1.3%) respectively. most (94%) s. sonnei isolates were resistant to co-trimoxazole. they wer ...200819069621
antibacterial activity of the broad bean extracts on resistant bacteria.the antimicrobial activities of four different extracts (ethanol, methanol, distilled water and 2-methylbutan-1-01) obtained from different parts of broad bean (vicia faba l.) such as flowers, leaves, seeds and seed hulls and were tested against bacillus subtilis, serratia marcescens, staphylococcus aureus, escherichia coli, klebsiella peneumoniua, shigella sp. and micrococcus pyogenes. better antimicrobial activity was observed with the leaves of broad bean sterile distilled water extract with ...200719069508
prevalence of sulfonamide resistance genes in bacterial isolates from manured agricultural soils and pig slurry in the united kingdom.the prevalences of three sulfonamide resistance genes, sul1, sul2, and sul3 and sulfachloropyridazine (scp) resistance were determined in bacteria isolated from manured agricultural clay soils and slurry samples in the united kingdom over a 2-year period. slurry from tylosin-fed pigs amended with scp and oxytetracycline was used for manuring. isolates positive for sul genes were further screened for the presence of class 1 and 2 integrons. phenotypic resistance to scp was significantly higher in ...200919064898
seasonal stability of cladophora-associated salmonella in lake michigan watersheds.the bacterial pathogens shigella, salmonella, campylobacter, and shiga toxin-producing e. coli (stec) were recently found to be associated with cladophora growing in southern lake michigan. preliminary results indicated that the salmonella strains associated with cladophora were genetically identical to each other. however, because of the small sample size (n=37 isolates) and a lack of information on spatial-temporal relationships, the nature of the association between cladophora and salmonella ...200919059626
tight junctions as targets of infectious agents.the epithelial barrier is a critical border that segregates luminal material from entering tissues. essential components of this epithelial fence are physical intercellular structures termed tight junctions. these junctions use a variety of transmembrane proteins coupled with cytoplasmic adaptors, and the actin cytoskeleton, to attach adjacent cells together thereby forming intercellular seals. breaching of this barrier has profound effects on human health and disease, as barrier deficiencies ha ...200919059200
characterization of shigella spp. by antimicrobial resistance and pcr detection of ipa genes in an infantile population from porto velho (western amazon region), brazil.the incidence of shigella spp. was assessed in 877 infants from the public hospital in rondônia (western amazon region, brazil) where shigella represents the fourth cause of diarrhea. twenty-five isolates were identified: 18 were shigella flexneri, three shigella sonnei, three shigella boydii and one shigella dysenteriae. with the exception of s. dysenteriae, all shigella spp. isolated from children with diarrhea acquired multiple antibiotic resistances. pcr detection of ipa virulence genes and ...200819057826
contribution of the periplasmic chaperone skp to efficient presentation of the autotransporter icsa on the surface of shigella flexneri.icsa is an outer membrane protein in the autotransporter family that is required for shigella flexneri pathogenesis. following its secretion through the sec translocon, icsa is incorporated into the outer membrane in a process that depends on yaet, a component of an outer membrane beta-barrel insertion machinery. we investigated the role of the periplasmic chaperone skp in icsa maturation. skp is required for the presentation of the mature amino terminus (alpha-domain) of icsa on the bacterial s ...200919047350
outbreaks where food workers have been implicated in the spread of foodborne disease. part 4. infective doses and pathogen carriage.in this article, the fourth in a series reviewing the role of food workers in foodborne outbreaks, background information on the presence of enteric pathogens in the community, the numbers of organisms required to initiate an infection, and the length of carriage are presented. although workers have been implicated in outbreaks, they were not always aware of their infections, either because they were in the prodromic phase before symptoms began or because they were asymptomatic carriers. pathoge ...200819044283
gef-h1 mediated control of nod1 dependent nf-kappab activation by shigella effectors.shigella flexneri has evolved the ability to modify host cell function with intracellular active effectors to overcome the intestinal barrier. the detection of these microbial effectors and the initiation of innate immune responses are critical for rapid mucosal defense activation. the guanine nucleotide exchange factor h1 (gef-h1) mediates rhoa activation required for cell invasion by the enteroinvasive pathogen shigella flexneri. surprisingly, gef-h1 is requisite for nf-kappab activation in re ...200819043560
selective ccr2-targeted macrophage depletion ameliorates experimental mesangioproliferative glomerulonephritis.the ccl2/ccr2 chemokine/receptor axis directs the chemotaxis of infiltrating monocytes/macrophages and t cells and plays a pivotal role in tissue damage and fibrosis in kidney diseases. the eradication of the activated leucocytes should diminish the production of inflammatory mediators, limit tissue damage and ameliorate disease. a recombinant fusion protein (opl-ccl2-lpm) comprised of the human ccl2 (monocyte chemoattractant protein-1) chemokine fused to a truncated form of the enzymatically ac ...200919040610
lactobacilli facilitate maintenance of intestinal membrane integrity during shigella dysenteriae 1 infection in rats.lactobacilli are used in various dairy products and fermented foods for their potential health beneficial effects. recently we reported the protective role of lactobacillus rhamnosus and lactobacillus acidophilus during shigella dysenteriae 1 infection. nevertheless, investigations on the membrane-stabilizing effect of l. rhamnosus and l. acidophilus have not been done. hence, the present study evaluated the effect of l. rhamnosus and l. acidophilus on the maintenance of intestinal membrane inte ...200919036564
the acrab-tolc pump is involved in multidrug resistance in clinical shigella flexneri isolates.the two multiple-antibiotic resistance (mar) phenotypes (n = 8, respectively) and susceptible isolates (n = 4) of shigella flexneri from china were characterized involving the efflux pump acrab-tolc. the accumulation of ciprofloxacin, acrab-tolc pcr, and levels of mrna with northern blots were performed in three groups. sequencing of acrab-tolc was performed in selected isolates. an efflux inhibition was performed with phe-arg-beta-naphthylamide. the accumulation of ciprofloxacin at steady state ...200819035770
interaction of enteric bacterial pathogens with murine embryonic stem cells.embryonic stem (es) cells are susceptible to genetic manipulation and retain the potential to differentiate into diverse cell types, which are factors that make them potentially attractive cells for studying host-pathogen interactions. murine es cells were found to be susceptible to invasion by salmonella enterica serovar typhimurium and shigella flexneri and to the formation of attaching and effacing lesions by enteropathogenic escherichia coli. s. enterica serovar typhimurium and s. flexneri c ...200919029302
antigen-specific b memory cell responses to lipopolysaccharide (lps) and invasion plasmid antigen (ipa) b elicited in volunteers vaccinated with live-attenuated shigella flexneri 2a vaccine candidates.we evaluated b memory responses in healthy adult volunteers who received one oral dose of live-attenuated shigella flexneri 2a vaccine. lps-specific b(m) cells increased from a median of 0 at baseline to 20 spot forming cells (sfc)/10(6) expanded cells following vaccination (p=0.008). a strong correlation was found between post-vaccination anti-lps b(m) cell counts and peak serum anti-lps igg titers (rs=0.95, p=0.0003). increases in b(m) specific for ipab approaching significance were also obser ...200919022324
spa32 interaction with the inner-membrane spa40 component of the type iii secretion system of shigella flexneri is required for the control of the needle length by a molecular tape measure mechanism.the effectors of enterocyte invasion by shigella are dependent on a type iii secretion system that contains a needle whose length average does not exceed 50 nm. previously, we reported that spa32 is required for needle length control as well as to switch substrate specificity from mxih to ipa proteins secretion. to identify functional domains of spa32, 11 truncated variants were constructed and analysed for their capacity (i) to control the needle's length; (ii) to secrete the ipa proteins; and ...200819019157
shigella flexneri type iii secretion system effectors ospb and ospf target the nucleus to downregulate the host inflammatory response via interactions with retinoblastoma protein.ospf, ospg and ipah(9.8) are type iii secretion system (t3ss) effectors of shigella flexneri that downregulate the host innate immune response. ospf modifies mitogen-activated protein kinase pathways and polymorphonuclear leucocyte transepithelial migration associated with shigella invasion. ospf also localizes in the nucleus to mediate chromatin remodelling, resulting in reduced transcription of inflammatory cytokines. we now report that ospb can be added to the set of s. flexneri t3ss effector ...200919017275
mxic is secreted by and controls the substrate specificity of the shigella flexneri type iii secretion apparatus.many gram-negative pathogenic bacteria use a type iii secretion (t3s) system to interact with cells of their hosts. mechanisms controlling the hierarchical addressing of needle subunits, translocators and effectors to the t3s apparatus (t3sa) are still poorly understood. we investigated the function of mxic, the member of the yopn/inve/sepl family in the shigella flexneri t3s system. inactivation of mxic led specifically to a deregulated secretion of effectors (including ipaa, ipgd, icsb, ipgb2, ...200919017268
espt triggers formation of lamellipodia and membrane ruffles through activation of rac-1 and cdc42.subversion of the eukaryotic cell cytoskeleton is a virulence strategy employed by many bacterial pathogens. due to the pivotal role of rho gtpases in actin dynamics they are common targets of bacterial effector proteins and toxins. ipgb1, ipgb2 (shigella), sifa, sifb (salmonella) and map and espm (attaching and effacing pathogens) constitute a family of type iii secretion system effectors that subverts small gtpase signalling pathways. in this study we identified and characterized espt from cit ...200919016787
inferring genomic flux in bacteria.acquisition and loss of genetic material are essential forces in bacterial microevolution. they have been repeatedly linked with adaptation of lineages to new lifestyles, and in particular, pathogenicity. comparative genomics has the potential to elucidate this genetic flux, but there are many methodological challenges involved in inferring evolutionary events from collections of genome sequences. here we describe a model-based method for using whole-genome sequences to infer the patterns of gen ...200919015321
is escherichia coli o157:h7 a common pathogen in children with bloody diarrhea in shiraz, iran?escherichia coli (e. coli) o157:h7 is a common cause of bloody diarrhea in developed countries. the aim of this study was to determine whether e. coli o157:h7 is a possible pathogen of bloody diarrhea in southern iran. out of 719 children with diarrhea, 243 (34%) patients with positive occult blood took part in our study. the polyclonal antibody test and polymerase chain reaction (pcr) were used to identify e. coli o157:h7. stool cultures showed enteropathogens in 107 patients (44%). shigella (3 ...200819014048
tlr4 and myd88 control protection and pulmonary granulocytic recruitment in a murine intranasal rsv immunization and challenge model.an intranasal vaccine composed of toll-like receptor 2 (tlr2) ligand neisseria meningitidis outer membrane proteins and toll-like receptor 4 (tlr4) ligand shigella flexneri lipopolysaccharide (lps) (protollin) and enriched respiratory syncytial virus (rsv) proteins (ersv) has been demonstrated to promote balanced th1/th2 responses without eosinophil recruitment and to protect against challenge in mouse models. we used tlr2, tlr4 and myeloid differentiation factor 88 (myd88) knock-out (-/-) mice ...200919013492
genotypic and phenotypic diversity among induced, stx2-carrying bacteriophages from environmental escherichia coli strains.shiga toxin 2 (stx(2)) gene-carrying bacteriophages have been shown to convert escherichia coli strains to shiga toxin-producing escherichia coli (stec). in this study, 79 e. coli strains belonging to 35 serotypes isolated from wastewaters of both human and animal origin were examined for the presence of stx(2)-carrying bacteriophages in their genomes. the lytic cycle of the bacteriophages was induced by mitomycin, and the bacteriophage fraction was isolated and used for morphological and geneti ...200919011056
repression of galp, the galactose transporter in escherichia coli, requires the specific regulator of n-acetylglucosamine metabolism.soupene et al. [j. bacteriol. (2003) 185 5611-5626] made the unexpected observation that the presence of a mutation, in the gene for the n-acetylglucosamine repressor, nagc, increased the growth rate of escherichia coli mg1655 on galactose, an unrelated sugar. we have found that nagc, binds to a single, high-affinity site overlapping the promoter of galp (galactose permease) gene and that expression of galp is repressed by a combination of nagc, galr and gals. in addition to the previously ident ...200919007420
functional nanoparticle-based proteomic strategies for characterization of pathogenic bacteria.although matrix-assisted laser desorption/ionization mass spectrometry (maldi ms) can be employed to rapidly characterize pathogenic bacteria, bacterial cultures are generally required to obtain sufficient quantities of the bacterial cells prior to maldi ms analysis. if this time-consuming step could be eliminated, the length of time required for identification of bacterial strains would be greatly reduced. in this paper, we propose an effective means of rapidly identifying bacteria--one that do ...200819007241
biometric fingerprinting for visa application: device and procedure are risk factors for infection transmission.biometric fingerprint identity verification is currently introduced in visa application and entry screening at border control. the system implies physical contact between the skin and the surface of the fingerprint-capturing and reading devices.200819006507
ceramide and cerebrosides from the octocoral sarcophyton ehrenbergi.chemical investigation of the octocoral sarcophyton ehrenbergi, collected at the dongsha islands, taiwan, has led to the isolation of a known ceramide (1) and two new cerebrosides, sarcoehrenosides a (2) and b (4), along with three known cerebrosides (3, 5, and 6). the structures of the new compounds were established by spectroscopic and chemical methods. sarcoehrenoside a (2) differs from previously known marine cerebrosides in that it possesses a rare alpha-glucose moiety. compounds 1-6 were e ...200919006372
[antibiotic resistance of bacterial strains in paediatric infections: there are resistance and resistance!].isolation of a bacterial strain at the infectious site and determination of the susceptibility profile may help to guide appropriate antibiotic treatment. however technical difficulties justify interpretative reading to recognize interfering resistance mechanisms from resistance phenotypes. the aim of this article is to give some examples showing interpretative reading of routine sensitivity test data.200819000854
the molecular evolutionary history of shigella spp. and enteroinvasive escherichia coli.shigellosis, which caused by shigella and enteroinvasive escherichia coli (eiec), was still a threat to public health. compelling evidence indicates that shigella species and eiec are derived from multiple origins of e. coli and form a single pathovar. eiec strains are regarded as precursors of 'full-blown'shigella evolved from e. coli. by gain and loss of functions, shigella and eiec became successful human pathogens through convergent evolution from diverse genomic backgrounds.200919000785
structure of a shigella effector reveals a new class of ubiquitin ligases.bacterial pathogens have evolved effector proteins with ubiquitin e3 ligase activities through structural mimicking. here we report the crystal structure of the shigella flexneri type iii effector ipah3, a member of the leucine-rich repeat (lrr)-containing bacterial e3 family. the lrr domain is structurally similar to yersinia pestis yopm and potentially binds to substrates. the structure of the c-terminal e3 domain differs from the typical ring- and hect-type e3s. ipah3 synthesizes a lys48-link ...200818997779
structure of the shigella t3ss effector ipah defines a new class of e3 ubiquitin ligases.ipah proteins are e3 ubiquitin ligases delivered by the type iii secretion apparatus into host cells upon infection of humans by the gram-negative pathogen shigella flexneri. these proteins comprise a variable leucine-rich repeat-containing n-terminal domain and a conserved c-terminal domain harboring an invariant cysteine residue that is crucial for activity. ipah homologs are encoded by diverse animal and plant pathogens. here we demonstrate that the ipah c-terminal domain carries the catalyti ...200818997778
small-molecule type iii secretion system inhibitors block assembly of the shigella type iii secreton.type iii secretion systems (t3sss) are essential virulence devices for many gram-negative bacteria that are pathogenic for plants, animals, and humans. they serve to translocate virulence effector proteins directly into eukaryotic host cells. t3sss are composed of a large cytoplasmic bulb and a transmembrane region into which a needle is embedded, protruding above the bacterial surface. the emerging antibiotic resistance of bacterial pathogens urges the development of novel strategies to fight b ...200918996990
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
the temporal dynamics of slightly deleterious mutations in escherichia coli and shigella spp.the shigella are recently emerged clones of escherichia coli, which have independently adopted an intracellular pathogenic lifestyle. we examined the molecular evolutionary consequences of this niche specialization by comparing the normalized, directional frequency profiles of unique polymorphisms within 2,098 orthologues representing the intersection of five e. coli and four shigella genomes. we note a surfeit of at-enriching changes (gc-->at), transversions, and nonsynonymous changes in the sh ...200918984902
a genomic distance based on mum indicates discontinuity between most bacterial species and genera.the fundamental unit of biological diversity is the species. however, a remarkable extent of intraspecies diversity in bacteria was discovered by genome sequencing, and it reveals the need to develop clear criteria to group strains within a species. two main types of analyses used to quantify intraspecies variation at the genome level are the average nucleotide identity (ani), which detects the dna conservation of the core genome, and the dna content, which calculates the proportion of dna share ...200918978054
novel chimeric beta-lactamase ctx-m-64, a hybrid of ctx-m-15-like and ctx-m-14 beta-lactamases, found in a shigella sonnei strain resistant to various oxyimino-cephalosporins, including ceftazidime.the plasmid-mediated novel beta-lactamase ctx-m-64 was first identified in shigella sonnei strain uih-1, which exhibited resistance to cefotaxime (mic, 1,024 microg/ml) and ceftazidime (mic, 32 microg/ml). the amino acid sequence of ctx-m-64 showed a chimeric structure of a ctx-m-15-like beta-lactamase (n- and c-terminal moieties) and a ctx-m-14-like beta-lactamase (central portion, amino acids 63 to 226), suggesting that it originated by homologous recombination between the corresponding genes. ...200918955524
the elucidation of the structure of the core part of the lps from plesiomonas shigelloides serotype o17 expressing o-polysaccharide chain identical to the shigella sonnei o-chain.plesiomonas shigelloides o17 lps contains the same o-antigenic polysaccharide chain as a causative agent of dysentery, shigella sonnei. this polysaccharide can be used as a component of a vaccine against dysentery. core part of the p. shigelloides o17 lps was studied using nmr and mass spectrometry and the following structure was proposed: [structure : see text]. significant similarity of the p. shigelloides o17 lps core with the structure of the p. shigelloides o54 core was observed.200818954864
analysis of immune responses and serological cross reactivities among vibrio cholerae o1, shigella flexneri 2a and haemophilus influenzae b.antigenic determinants expressed on the bacterial cell surface are of importance in the serological characterization and microbiological diagnosis. the bacterial strains carrying these identical or similar antigenic epitopes might react with antibodies produced against other strains. in this study, strong immunogenicity and antigenic cross reactivity were demonstrated among v. cholerae o1, s. flexnerii 2a and h. influenzae b surface components. the enzyme linked immunosorbent assay (elisa) resul ...200818954564
detection of protozoan and bacterial pathogens of public health importance in faeces of corvus spp. (large-billed crow).parasites and bacteria are reported in the faeces of birds in the current study. fresh faecal samples of the large-billed crow (corvus spp.) were collected from the study site at bangsar, an urban setting in kuala lumpur, malaysia. these samples were transported to laboratory and analysed for parasites and bacteria. pre-prepared xld agar plates were used for culturing the bacteria in the laboratory. using the api 20etm test strips, 9 different species of bacteria were identified belonging to the ...200818948884
antimicrobial activity of endemic crataegus tanacetifolia (lam.) pers and observation of the inhibition effect on bacterial cells.up to now an increasing number of antibiotic-resistant bacteria have been reported and thus new natural therapeutic agents are needed in order to eradicate these pathogens. through the discovery of plants such as crataegus tanacetifolia (lam.) pers that have antimicrobial activity, it will be possible to discover new natural drugs serving as chemotherapeutic agents for the treatment of nosocomial pathogens and take these antibiotic-resistant bacteria under control. the objective of the present s ...200818946875
structural characterization of the type-iii pilot-secretin complex from shigella flexneri.assembly of the type-iii secretion apparatus, which translocates proteins through both membranes of gram-negative bacterial pathogens into host cells, requires the formation of an integral outer-membrane secretin ring. typically, a small lipidated pilot protein is necessary for the stabilization and localization of this ring. using nmr spectroscopy, we demonstrate that the c-terminal residues 553-570 of the shigella flexneri secretin mxid encompass the minimal binding domain for its cognate pilo ...200818940609
a pilot sheds light on secretin assembly. 200818940600
diversity of tight junctions (tjs) between gastrointestinal epithelial cells and their function in maintaining the mucosal barrier.the gastrointestinal epithelium, which is covered by a single layer of epithelial cells, including enterocytes, intraepithelial lymphocytes, goblet cells, microfold cells, and dendritic cells, serves as a protective barrier separating luminal contents from the underlying tissue compartments. the epithelium plays an important role in the first line of host defense against a variety of pathogens, as well as maintaining the homeostasis in gastrointestinal tract. all these epithelial cells express j ...200918938254
the isolation and properties of specific antigens from variants of shigella sonnei. 194818932531
simultaneous detection of enteric bacteria from surface waters by qpcr in comparison with conventional bacterial indicators.a rapid quantitative polymerase chain reaction (qpcr) method was developed for simultaneous detection of enteric bacteria from surface waters by utilizing a pair of universal primers which targeted four bacteria strains, namely shigella dysenteriae, vibrio cholerae, salmonella typhimurium, and escherichia coli. it was estimated that the qpcr method had a 94% confidence, and a detection limit as 2.7 e. coli cells per sample in undiluted dna extracts. the qpcr method was applied for the bacteriolo ...200918931927
porin-incorporated liposome induces toll-like receptors 2- and 6-dependent maturation and type 1 response of dendritic cell.porin of shigella dysenteriae was incorporated in liposome (pil) and presented to mouse splenic dendritic cells (dc). pil up-regulated toll-like receptor (tlr) 2 and tlr6 on dc, showing that co-expression of the two tlrs is involved in recognition of porin. detection of myeloid differentiating factor 88 (myd88)-tlr2 complex confirmed interaction between the two for triggering the downstream signaling, which ultimately led to tlr2-dependent nuclear translocation of nuclear factor-kappa b. pil-ind ...200818931363
closing the diarrhoea diagnostic gap in indian children by the application of molecular techniques.a large proportion of diarrhoeal illnesses in children in developing countries are ascribed to an unknown aetiology because the only available methods, such as microscopy and culture, have low sensitivity. this study was aimed at decreasing the diagnostic gap in diarrhoeal disease by the application of molecular techniques. faecal samples from 158 children with and 99 children without diarrhoea in a hospital in south india were tested for enteric pathogens using conventional diagnostic methods ( ...200818927413
in this issue: proteomics 20/2008.in this issue of proteomics you will find the following highlighted articles:comprehensively confirmed annotation of short orfsduring the california gold rush, prospectors did not look only for large nuggets to pave their road to riches - they also collected gold dust. the proteomic equivalent of dust is the small orf. it does not pay to put a lower limit on dust or orf size because almost any size may be turned into "cash" or an important peptide. wei et al. demonstrate how a combination of con ...200818924177
experimental type transformation of shigella paradysenteriae (flexner). 194718921755
on some culture media used for the isolation of salmonella, eberthella and shigella organisms. 194718920730
a case of shigella alkalescens cystopyelitis and bacteremia. 194818920536
shigella tieté. 194818915661
studies on the genus shigella. 194718915385
an outbreak of shigella flexneri infection among rheus monkeys. 194818915380
[not available]. 194818911146
hemagglutination by bacterial suspensions with special reference to shigella alkalescens. 194818910635
[not available]. 194818908201
contribution to the diagnosis of shigellae and salmonellae in the tropics. 194718899852
responses of human subjects to vaccines in saline-in-mineral oil emulsion; shigella paradysenteriae vaccines. 194818897990
shigella rio, a new type of shigella. 194818897988
the relation of antagonistic coliform organisms to shigella infections; observations in acute infections. 194818890195
enteric infections in chimpanzees and spider monkeys with special reference to a sulfadiazine resistant shigella. 194818888330
studies in dysentery vaccination; primary vaccination of children with monovalent vaccines of shigella. 194818886530
studies in dysentery vaccination; immunization of mice with vaccine of shigella sonnei administered by gavage. 194818881080
the relation of antabonistic coliform organisms to shigella infections; survey observations. 194818881069
[not available]. 194818878713
[not available]. 194818878174
susceptibility of mongoloids to infection; incidence of pneumonia, influenza a and shigella dysenteriae, sonne. 194818872694
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