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the pathogenic properties of a novel and conserved gene product, kerv, in proteobacteria.identification of novel virulence factors is essential for understanding bacterial pathogenesis and designing antibacterial strategies. in this study, we uncover such a factor, termed kerv, in proteobacteria. experiments carried out in a variety of eukaryotic host infection models revealed that the virulence of a pseudomonas aeruginosa kerv null mutant was compromised when it interacted with amoebae, plants, flies, and mice. bioinformatics analyses indicated that kerv is a hypothetical methyltra ...200919779606
secretory iga-mediated neutralization of shigella flexneri prevents intestinal tissue destruction by down-regulating inflammatory circuits.shigella, a gram-negative invasive enteropathogenic bacterium responsible for bacillary dysentery, causes the rupture, invasion, and inflammatory destruction of the human colonic mucosa. we explored the mechanisms of protection mediated by shigella lps-specific secretory iga (siga), the major mucosal ab induced upon natural infection. bacteria, siga, or siga-s. flexneri immune complexes were administered into rabbit ligated intestinal loops containing a peyer's patch. after 8 h, localizations of ...200919828639
magnitude of drug resistant shigellosis: a report from bangalore.shigella is an important cause of acute invasive diarrhea in children and others. antimicrobial susceptibility of shigella spp. isolated from diarrhoeal/ dysenteric patients in bangalore was studied in our hospital from january 2002 to december 2007. one hundred and thirty-four isolates were identified as shigella species. s. flexneri, s. sonnei , s. boydii and s. dysenteriae were accounted respectively for 64.9%, 21.6%, 8.2% and 3.7% of the total number of shigella isolated. of these 56 (41.8%) ...200919736408
transmission risk factors and treatment of pediatric shigellosis during a large daycare center-associated outbreak of multidrug resistant shigella sonnei: implications for the management of shigellosis outbreaks among children.shigellosis outbreaks in daycare centers result in substantial disease and economic burdens in the united states. the emergence of multidrug resistant shigella strains raises questions regarding control of transmission within daycare centers and treatment for children. from may to october 2005, 639 shigella sonnei cases were reported in northwest missouri, mostly among persons exposed to daycare centers.200919738503
effect of x-ray treatments on inoculated escherichia coli o157: h7, salmonella enterica, shigella flexneri and vibrio parahaemolyticus in ready-to-eat shrimp.this study was conducted to evaluate the inactivation effect of x-ray treatments on escherichia coli o157: h7, salmonella enteric (s. enterica), shigella flexneri (s. flexneri) and vibrio parahaemolyticus (v. parahaemolyticus) artificially inoculated in ready-to-eat (rte) shrimp. a mixed culture of three strains of each tested pathogen was used to inoculate rte shrimp. the shrimp samples were inoculated individually with selected pathogenic bacteria then aseptically placed in sterile plastic cup ...200919835772
the mannitol operon repressor mtlr belongs to a new class of transcription regulators in bacteria.many bacteria express phosphoenolpyruvate-dependent phosphotransferase systems (pts). the mannitol-specific pts catalyze the uptake and phosphorylation of d-mannitol. the uptake system comprises several genes encoded in the single operon. the expression of the mannitol operon is regulated by a proposed transcriptional factor, mannitol operon repressor (mtlr) that was first studied in escherichia coli. here we report the first crystal structures of mtlr from vibrio parahemeolyticus (vp-mtlr) and ...200919840941
autophagy in immunity against intracellular bacteria.autophagy is an innate immune defense mechanism against various intracellular bacterial pathogens, such as salmonella enterica serovar typhimurium (s. typhimurium), listeria monocytogenes and shigella flexneri. s. typhimurium uses type three secretion systems (t3sss) to invade mammalian cells and replicate in salmonella-containing vacuoles (scvs). a small population of intracellular s. typhimurium is targeted by autophagy shortly after infection. evidence suggests that these bacteria are present ...200919802566
spa15 of shigella flexneri is secreted through the type iii secretion system and prevents staurosporine-induced apoptosis.shigella flexneri is a gram-negative, facultative intracellular pathogen that invades the colonic epithelium and causes bacillary dysentery. we previously demonstrated that s. flexneri inhibits staurosporine-induced apoptosis in infected epithelial cells and that a deltamxie mutant is unable to inhibit apoptosis. therefore, we hypothesized that an mxie-regulated gene was responsible for protection of epithelial cells from apoptosis. analysis of all mxie-regulated genes yielded no mutants that la ...200919805534
assessment of cell surface properties and adhesion potential of selected probiotic strains.to evaluate the physicochemical cell surface and adhesive properties of selected probiotic strains for human use.200919725886
comparison of the entericbio multiplex pcr system with routine culture for detection of bacterial enteric pathogens.the entericbio system uses a multiplex pcr assay for the simultaneous detection of campylobacter spp., salmonella enterica, shigella spp., and escherichia coli o157 from feces. it combines overnight broth enrichment with pcr amplification and detection by hybridization. an evaluation of this system was conducted by comparing the results obtained with the system with those obtained by routine culture, supplemented with alternative pcr detection methods. in a study of 773 samples, routine culture ...200919726596
nonculturable response of animal enteropathogens in the agricultural environment and implications for food safety.concerns about animal enteropathogen contamination of fresh horticultural products have,increased worldwide and are mainly due to the ability of bacteria to survive under stress conditions in the agricultural environment and during raw-vegetable processing. this review challenges the idea that the viable but nonculturable phenomenon that has been proven to occur in plant-associated environments contributes to human pathogen survival and might be correlated with foodborne infection. factors assoc ...200919610353
oxidative and antibacterial activity of mn3o4.mn(3)o(4) nanoparticles with diameter ca. 10nm were synthesized by the forced hydrolysis of mn(ii) acetate at 80 degrees c. the x-ray diffraction (xrd), fourier transform infra red (ft-ir) spectroscopy, scanning electron microscopy (sem) and energy dispersive x-ray (edx) techniques were employed to study structural features and chemical composition of the nanoparticles. the unique oxidative activity of the mn(3)o(4) nanoparticles was demonstrated in the polymerization and dye degradation reactio ...200919733434
[rapid detection of salmonella in food by using fluorescently labeled phage o-i].to develop a rapid detection method for salmonella in food by using specific salmonella-phage o-i.200919623962
peptide sequences identified by phage display are immunodominant functional motifs of pet and pic serine proteases secreted by escherichia coli and shigella flexneri.plasmid-encoded toxin (pet) and protein involved in colonization (pic), are serine protease autotransporters of enterobacteriaceae (spates) secreted by enteroaggregative escherichia coli (eaec), which display the gdsgsg sequence or the serine motif. our research was directed to localize functional sites in both proteins using the phage display method. from a 12mer linear and a 7mer cysteine-constrained (c7c) libraries displayed on the m13 phage piii protein we selected different mimotopes using ...200919772881
study on induction of apoptosis on hela and vero cells by recombinant shiga toxin and its subunits.verotoxin (vt) or shiga toxin (stx) produced by enterohemorrhagic escherichia coli (ehec) and shigella dysenteriae is ab5 holotoxin with potent protein synthesis inhibitor. vt can induce both apoptosis and necrosis depending on the cell type, it has been shown that vt-induced apoptosis and cytotoxicity are distinct processes, and the a subunit can be necessary for apoptosis. in other words, the precise role of each subunit in apoptosis signaling has yet to be established. in this study, inductio ...200919669659
broad-range pcr, cloning and sequencing of the full 16s rrna gene for detection of bacterial dna in synovial fluid samples of tunisian patients with reactive and undifferentiated arthritis.broad-range rdna pcr provides an alternative, cultivation-independent approach for identifying bacterial dna in reactive and other form of arthritis. the aim of this study was to use broad-range rdna pcr targeting the 16s rrna gene in patients with reactive and other forms of arthritis and to screen for the presence of dna from any given bacterial species in synovial fluid (sf) samples.200919570210
review article: anti-inflammatory mechanisms of action of saccharomyces boulardii.saccharomyces boulardii, a well-studied probiotic, can be effective in inflammatory gastrointestinal diseases with diverse pathophysiology, such as inflammatory bowel disease (ibd), and bacterially mediated or enterotoxin-mediated diarrhoea and inflammation.200919706150
high-affinity inhibitors of trna-guanine transglycosylase replacing the function of a structural water cluster.the trna-modifying enzyme trna-guanine transglycosylase (tgt) is essential for the pathogenic mechanism of shigella flexneri, the causing agent of the bacterial diarrheal disease shigellosis. herein, the synthesis of a new class of rationally designed 6-amino-imidazo[4,5-g]quinazolin-8(7h)-one- (lin-benzoguanine) based inhibitors of tgt are reported. in order to accommodate a small hydrophobic crevice opening near the binding site of ribose-34, 2-aminoethyl substituents were introduced in positi ...200919746363
aetiology of acute gastro-enteritis in children at saint camille medical centre, ouagadougou, burkina faso.the present study aims at identifying the infectious agents responsible for child acute gastroenteritis (age) in ouagadougou. from may 5 2006 to june 22 2008, 648 children aged from 2 to 41 months, with at least an average of 3 loose stools per day have been enrolled for coproculture, parasitology and virology test. among them, 34 (5.25%) were hiv seropositive. a single sample of faeces from each child was used to identify enteropathogens. an infectious aetiology was identified in 41.20% of case ...200919579955
[development of single base extension-tags microarray for the detection of food-borne pathogens].we developed single base extension-tags (sbe-tags) microarray to detect eight common food-borne pathogens, including staphylococcus aureus, vibrio parahaemolyticus, listeria monocytogenes, salmonella, enterobacter sakazaki, shigella, escherichia coli o157:h7 and campylobacter jejuni. with specific pcr primers identified and integrated for eight food-borne pathogens, target sequences were amplified and purified as template dna of single base extension-tags reaction. the products were hybridized t ...200919637631
structural insights into host gtpase isoform selection by a family of bacterial gef mimics.the escherichia coli type iii effector map belongs to a large family of bacterial virulence factors that activate host rho gtpase signaling pathways through an unknown molecular mechanism. here we report direct evidence that map functions as a potent and selective guanine-nucleotide exchange factor (gef) for cdc42. the 2.3-a structure of the map-cdc42 complex revealed that map mimics the gef strategy of the mammalian dbl family but has a three-dimensional architecture that is nearly identical to ...200919620963
[virulence factors and in vitro susceptibility of plesiomonas shigelloides isolated from diarrhea episodes in cuba].acute diarrhea is still one of the main causes of disease in developing countries. at the national reference laboratory for acute diarrhoeal diseases, of the "pedro kourí" tropical medicine institute, 54 plesiomonas shigelloides strains were serotyped. as a result, the circulation of four new serotypes (o20:h2, 056:h18, 071 :h31,081 :h22) was detected. the most common antigenic variant was 094:h3. in addition, the susceptibility pattern to 21 antimicrobial agents (aa) was studied. highest percen ...200919621156
computational study of the conformational structures of saccharides in solution based on j couplings and the "fast sugar structure prediction software".this article reports on the implementation of j coupling calculations in our recently developed fast sugar structure prediction software (fsps). the fsps combines a smart and exhaustive algorithm to search through conformational space with the calculation of different experimental nuclear magnetic resonance observables to establish the conformation of saccharides in solution. using our algorithm in combination with nmr data, we investigate the solution structure of three simple disaccharides (me ...200919795837
vaccination of children in low-resource countries against shigella is unlikely to present an undue risk of reactive arthritis.shigellosis is a major cause of morbidity and mortality among children in low-resource countries. promising vaccine strategies in development include genetically attenuated shigella, killed whole cell vaccines, subcellular vaccines, and o-polysaccharide-protein conjugates. there is a concern that shigella vaccines could either induce reactive arthritis or could prime vaccinees for arthritis after a subsequent exposure to the pathogen because shigellosis is associated with reactive arthritis, esp ...200919643213
increasing resistance to nalidixic acid in shigella subgroups in a comparative study between 2001-2003 and 2004-2006.the shigella spp. is an organism with an ongoing changing resistance pattern to different antibiotics, thus making its appropriate treatment difficult. nalidixic acid has been one of the most common agents used for the treatment of shigellosis. recently, some studies have reported an emerging resistance to this agent.200919710978
uropathogenic escherichia coli suppresses the host inflammatory response via pathogenicity island genes sisa and sisb.extraintestinal pathogenic escherichia coli can successfully colonize the urinary tract of the immunocompetent host. in part, this is accomplished by dampening the host immune response. indeed, the sisa and sisb genes (shia-like inflammation suppressor genes a and b) of uropathogenic e. coli strain cft073, homologs of the shigella flexneri shi-2 pathogenicity island gene shia, suppress the host inflammatory response. a double deletion mutant (deltasisa deltasisb) resulted in a hyperinflammatory ...200919797063
effects of enteropathogenic bacteria & lactobacilli on chemokine secretion & toll like receptor gene expression in two human colonic epithelial cell lines.the intestinal epithelium is part of the innate immune system responding to contact with pathogenic or commensal bacteria. the objective of this study was to compare innate responses of intestinal epithelial cell lines to pathogenic bacteria and to lactobacilli.200919797815
multiplexed bead-based mesofluidic system for detection of food-borne pathogenic bacteria.in the present study, a simple and rapid multiplexed bead-based mesofluidic system (bms) was developed for simultaneous detection of food-borne pathogenic bacteria, including staphylococcus aureus, vibrio parahaemolyticus, listeria monocytogenes, salmonella, enterobacter sakazakii, shigella, escherichia coli o157:h7, and campylobacter jejuni. this system is based on utilization of isothiocyanate-modified microbeads that are 250 mum in diameter, which were immobilized with specific amino-modified ...200919717622
proteome analysis of an attenuated francisella tularensis dsba mutant: identification of potential dsba substrate proteins.francisella tularensis (f. tularensis) is highly infectious for humans via aerosol route and untreated infections with the highly virulent subsp. tularensis can be fatal. our knowledge regarding key virulence determinants has increased recently but is still somewhat limited. surface proteins are potential virulence factors and therapeutic targets, and in this study, we decided to target three genes encoding putative membrane lipoproteins in f. tularensis lvs. one of the genes encoded a protein w ...200919799467
high frequency of hotspot mutations in core genes of escherichia coli due to short-term positive selection.core genes comprising the ubiquitous backbone of bacterial genomes are not subject to frequent horizontal transfer and generally are not thought to contribute to the adaptive evolution of bacterial pathogens. we determined, however, that at least one-third and possibly more than one-half of the core genes in escherichia coli genomes are targeted by repeated replacement substitutions in the same amino acid positions-hotspot mutations. occurrence of hotspot mutations is driven by positive selectio ...200919617543
an outbreak of shigella dysenteriae in sweden, may-june 2009, with sugar snaps as the suspected source.we report an outbreak of shigella dysenteriae type 2 infections during may-june 2009 in sweden, involving 47 suspected cases of whom 35 were laboratory-confirmed. the epidemiological investigation based on interviews with the patients pointed at sugar snaps from kenya as the source. shigella was not detected in samples of sugar snaps. however, escherichia coli was confirmed in three of four samples indicating contamination by faecal material. during april to may 2009 outbreaks with shigella conn ...200919607782
enterohaemorrhagic escherichia coli serogroup o111 inhibits nf-(kappa)b-dependent innate responses in a manner independent of a type iii secreted ospg orthologue.enterohaemorrhagic and enteropathogenic escherichia coli (ehec and epec) inject a repertoire of effector proteins into host cells via a type iii secretion system (t3ss) encoded by the locus of enterocyte effacement (lee). ospg is an effector protein initially identified in shigella that was shown to inhibit the host innate immune response. in this study, we found ospg homologues in ehec (mainly of serogroup o111) and in yersinia enterocolitica. the t3ss encoded by the lee was able to inject thes ...200919628559
differentiation of whole bacterial cells based on high-throughput microarray chip printing and infrared microspectroscopic readout.using robotic automation, a microarray printing protocol for whole bacterial cells was developed for subsequent label-free and nondestructive infrared microspectroscopic detection. using this contact microspotting system, 24 microorganisms were printed on zinc selenide slides; these were 6 species of listeria, 10 species of vibrio, 2 strains of photobacterium damselae, yersinia enterocolitica 289, bacillus cereus atcc 14529, staphylococcus aureus, atcc 19075 (serotype 104 b), shigella sonnei 201 ...200919630511
physicochemical, nutritional and antibacterial characteristics of the fruit of bromelia pinguin l.bromelia pinguin l. is a plant native to sinaloa, mexico, where its fruit is used as food or as a phytotherapeutic agent. the fruits of b. pinguin were characterized and they could be considered as a functional food. these fruits show an average weight of 13.7 g and a yellow color of high luminosity (b* = 43.2, l* = 74.5). the values for acidity (4.6%, as citric acid) and ph (3.7) of b. pinguin fruit are similar to those of citrics. the edible portion is characterized by a high content of vitami ...200919536651
antibiotic resistance among bacterial pathogens in central africa: a review of the published literature between 1955 and 2008.a systematic review of the published literature on bacterial resistance in central africa between 1955 and 2008 was performed. eighty-three publications from seven countries were retrieved, the majority presenting data on enteric and other gram-negative pathogens. despite methodological limitations in many studies, alarming resistance rates are noted in nearly all pathogens. of special concern are multidrug resistance in shigella and salmonella spp. and the emergence of meticillin-resistant stap ...200919540725
hospital-based surveillance of enteric parasites in kolkata.diarrhoea is the second leading cause of illness and death in developing countries and the second commonest cause of death due to infectious diseases among children under five in such countries. parasites, as well as bacterial and viral pathogens, are important causes of diarrhoea. however, parasitic infections are sometimes overlooked, leading after a period of time to an uncertain aetiology. in this paper we report the prevalence of giardia lamblia, entamoeba histolytica and cryptosporidium sp ...200919545355
nitric oxide production in acute gastroenteritis in indian children.this study compared nitric oxide (no) levels in 110 children with, and 110 children without, infectious gastroenteritis. post-infection intestinal function was assessed in a subset. at least one pathogen was identified in 47.2% of cases. the most common diarrhoeal pathogens were rotavirus (22.7%) and norovirus genogroup ii (11.8%). the levels of no measured by median urinary nitrite:creatinine ratio were significantly higher in children with diarrhoea [23.6; interquartile range (iqr) 12.3-46.7] ...200919552932
comparison of two label-free global quantitation methods, apex and 2d gel electrophoresis, applied to the shigella dysenteriae proteome.the in vitro stationary phase proteome of the human pathogen shigella dysenteriae serotype 1 (sd1) was quantitatively analyzed in coomassie blue g250 (cbb)-stained 2d gels. more than four hundred and fifty proteins, of which 271 were associated with distinct gel spots, were identified. in parallel, we employed 2d-lc-ms/ms followed by the label-free computationally modified spectral counting method apex for absolute protein expression measurements. of the 4502 genome-predicted sd1 proteins, 1148 ...200919563668
enteric bacterial pathogens in hiv-infected children with acute diarrhea in mulago referral and teaching hospital, kampala, uganda.hiv-infected children develop severe bacterial infections. we set out to determine the enteric bacterial pathogens in hiv-infected children and hiv-negative controls with acute diarrhea and their antimicrobial sensitivities.200919357426
structure and heme binding properties of escherichia coli o157:h7 chux.for many pathogenic microorganisms, iron acquisition from host heme sources stimulates growth, multiplication, ultimately enabling successful survival and colonization. in gram-negative escherichia coli o157:h7, shigella dysenteriae and yersinia enterocolitica the genes encoded within the heme utilization operon enable the effective uptake and utilization of heme as an iron source. while the complement of proteins responsible for heme internalization has been determined in these organisms, the f ...200919319934
ipab-ipgc interaction defines binding motif for type iii secretion translocator.the delivery of virulence factors into host cells through type iii secretion systems is essential for enterobacterial pathogenesis. molecular chaperones bind specifically to virulence factors in the bacterial cytosol before secretion. invasion plasmid gene c (ipgc) is a chaperone that binds 2 essential virulence factors of shigella: invasion plasmid antigens (ipa) b and c. here, we report the crystal structure of ipgc alone and in complex with the chaperone binding domain (cbd) of ipab. the chap ...200919478065
preliminary foodnet data on the incidence of infection with pathogens transmitted commonly through food--10 states, 2008.foodborne diseases remain an important public health problem in the united states. the foodborne diseases active surveillance network (foodnet) of cdc's emerging infections program collects data from 10 u.s. states on diseases caused by enteric pathogens transmitted commonly through food. foodnet is an active, population-based surveillance system for these laboratory-confirmed infections. this report describes preliminary surveillance data for 2008 and trends since 1996. in 2008, the estimated i ...200919357633
potent bactericidal action of a flavonoid fraction isolated from the stem bark of butea frondosa.the flavonoid fraction isolated from the ethyl acetate fraction (bf-1) of butea frondosa (l.) stem bark exhibited distinct antimicrobial activity when tested against 129 bacterial strains belonging to 9 different genera of both gram-positive and gram-negative types. minimum inhibitory concentration (mic) of the fraction bf-1 was determined following nccls guidelines using the agar dilution method. twenty-four out of 36 strains of staphylococcus aureus were inhibited by 50-200 mg/l of the fractio ...200919368121
intuitionistic fuzzy set vs. fuzzy set application in medical pattern recognition.one of the toughest challenges in medical diagnosis is uncertainty handling. the detection of intestinal bacteria such as salmonella and shigella which cause typhoid fever and dysentery, respectively, is one such challenging problem for microbiologists. they detect the bacteria by the comparison with predefined classes to find the most similar one. consequently, we observe uncertainty in determining the similarity degrees, and therefore, in the bacteria classification. in this paper, we take an ...200919375899
[complete structure of the o-polysaccharide from shigella dysenteriae type 10].the structure of the o-specific polysaccharide from shigella dysenteriae type 10, which has been reported previously in bioorg. khim. (1977, vol. 3, pp. 1219-1225), was refined: [formula: see text].200919377533
protein interaction platforms: visualization of interacting proteins in yeast.here we describe the protein interaction platform assay, a method for identifying interacting proteins in saccharomyces cerevisiae. this assay relies on the reovirus scaffolding protein microns, which forms large focal inclusions in living cells. when a query protein is fused to microns and potential interaction partners are fused to a fluorescent reporter, interactors can be identified by screening for yeast that display fluorescent foci.200919483691
lack of antimicrobial activity by the antiretroviral drug nevirapine against common bacterial pathogens. 200919487448
bacteria hijack integrin-linked kinase to stabilize focal adhesions and block cell detachment.the rapid turnover and exfoliation of mucosal epithelial cells provides an innate defence system against bacterial infection. nevertheless, many pathogenic bacteria, including shigella, are able to surmount exfoliation and colonize the epithelium efficiently. here we show that the shigella flexneri effector ospe (consisting of ospe1 and ospe2 proteins), which is highly conserved among enteropathogenic escherichia coli, enterohaemorrhagic e. coli, citrobacter rodentium and salmonella strains, rei ...200919489119
purification and characterization of an immunogenic outer membrane protein of shigella flexneri 2a.in the present study we purified 34 kda major outer membrane protein (momp) of shigella flexneri 2a for the first time, which was cross-reactive and antigenically conserved among shigella spp. and the epitope was surface exposed on the intact bacterium. the purified antigen was found to be glycosylated, which aids in binding to macrophages and up-regulated the production of nitric oxide, granulocyte-colony stimulating factor and il-12p70, indicating that the momp is immunogenic and has the abili ...200919660587
screening, purification, and identification of the enzyme producing n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester from l-isoasparagine and l-phenylalanine methyl ester.screening was carried out for microorganisms able to produce n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester [apm] from l-isoasparagine and l-phenylalanine methyl ester hydrochloride. of the 422 strains examined, 44 strains belonging to the family enterobacteriaceae were found to produce apm. the enzyme catalyzing apm production was purified and identified as dipeptidase e.200919664550
potential applicability of chymotrypsin-susceptible microcin j25 derivatives to food preservation.microcin j25 (mccj25) is a 21-residue ribosomally synthesized lariat peptide antibiotic. mccj25 is active against such food-borne disease-causing pathogens as salmonella spp., shigella spp., and escherichia coli, including e. coli o157:h7 and non-o157 strains. mccj25 is highly resistant to digestion by proteolytic enzymes present in the stomach and intestinal contents. mccj25 would therefore remain active in the gastrointestinal tract, affecting normal intestinal microbiota, and this limits the ...200919592527
porin of shigella dysenteriae directly promotes toll-like receptor 2-mediated cd4+ t cell survival and effector function.porin of shigella dysenteriae type 1 up-regulated toll-like receptor (tlr)2 on cd3-stimulated cd4(+) t cells but could not induce the expression of other tlrs. tlr2 in association with myeloid differentiating factor 88 (myd88) triggered the downstream signal transduction pathway leading to activation of mitogen-activated protein kinase (mapk) and nuclear factor kappab (nf-kappab), and degradation of ikappab, the nf-kappab inhibitor. tlr2 co-stimulation by porin resulted in t cell expansion by in ...200919576636
bacterial jailbreak sounds cellular alarm: phagosome membrane remnants trigger signaling.shigella flexneri and other invasive bacteria rupture the phagosome membrane and escape to the host cytoplasm. now, dupont et al. address the fate and signaling functions of pathogen vacuole remnants and show that these membrane fragments trigger host-cell-signaling responses, including polyubiquitination, autophagy, and pyroptosis.200919683675
shigella phagocytic vacuolar membrane remnants participate in the cellular response to pathogen invasion and are regulated by autophagy.intracellular pathogens like shigella flexneri enter host cells by phagocytosis. once inside, the pathogen breaks the vacuolar membrane for cytosolic access. the fate and function of the vacuolar membrane remnants are not clear. examining shigella-infected nonmyeloid cells, we observed that proteins associated with vacuolar membrane remnants are polyubiquinated, recruit the autophagy marker lc3 and adaptor p62, and are targeted to autophagic degradation. further, inflammasome components and casp ...200919683680
a genome-scale proteomic screen identifies a role for dnak in chaperoning of polar autotransporters in shigella.autotransporters are outer membrane proteins that are widely distributed among gram-negative bacteria. like other autotransporters, the shigella autotransporter icsa, which is required for actin assembly during infection, is secreted at the bacterial pole. in the bacterial cytoplasm, icsa localizes to poles and potential cell division sites independent of the cell division protein ftsz. to identify bacterial proteins involved in the targeting of icsa to the pole in the bacterial cytoplasm, we sc ...200919684128
protective role of mouse mbl-c on intestinal mucosa during shigella flexneri invasion.mannan-binding lectin (mbl) is a c-type serum lectin, which is believed to play an important role in the innate immunity against a variety of pathogens. mbl can bind to sugar determinants of a wide variety of microorganisms, neutralize them and inhibit infection by complement activation through the lectin pathway and opsonization by collectin receptors. given that small intestine is a predominant site of extrahepatic expression of mbl, here we addressed the question whether mbl is involved in mu ...200919684159
sarcosaprophagous flies in suez governorate, egypt iv--persistence of human pathogenic bacteria in the developmental stages.the persistence of three species of human pathogenic bacteria (escherichia coli, shigella sonnei and staphylococcus epidermidis) in sterile artificially fed larvae was examined till adult emergence after ingestion by three species of sarcosaprophagous flies (house fly, musca domestica, oriental latrine blow fly, chrysomya megacephala and australian cheep blow fly, lucilia cuprina). the number of bacteria present in mature maggots, pupae and emerging adults declined significantly (p < 0.05). each ...200919530618
effects of reduction products of ortho-hydroxyl substituted azo dyes on biodecolorization of azo dyes.the mediated effects of reduction products of some ortho-hydroxyl substituted azo dyes on biodecolorization were investigated. the results indicated that the addition of reduction products could effectively accelerate dye decolorization by shigella sp. qrz-1. the best accelerating effect was obtained with the addition of reduction products of acid red 14 (ar14), resulting in an over 3-fold increase in decolorization efficiency of many azo dyes. in sequencing batch reactor experiments, the accele ...200919545943
influence of long-term consumption of a lactococcus lactis strain on the intestinal immunity and intestinal flora of the senescence-accelerated mouse.the senescence-accelerated mouse develops normally until 5-6 months of age and then displays rapid and irreversible advancement of senescence manifesting as clinical signs and gross lesions. to clarify the effect of lactic acid bacteria on the physiological changes with increasing age, heat-killed lactococcus lactis g50 was administered to 1-month-old senescence-accelerated-prone mouse (samp)6 mice for 11 months, a senescence-accelerated mouse strain that develops senile osteoporosis. mice fed g ...200919586567
a novel glucosyltransferase involved in o-antigen modification of shigella flexneri serotype 1c.the o antigen of serotype 1c differs from the unmodified o antigen of serotype y by the addition of a disaccharide (two glucosyl groups) to the tetrasaccharide repeating unit. it was shown here that addition of the first glucosyl group is mediated by the previously characterized gtri cluster, which is found within a cryptic prophage at the proa locus in the bacterial chromosome. transposon mutagenesis was performed to disrupt the gene responsible for addition of the second glucosyl group, causin ...200919717593
characterization of shigella sonnei isolates from travel-associated cases in japan.shigella sonnei infection in industrialized countries is often associated with foreign travel. a total of 195 s. sonnei isolates in japan, isolated from cases associated with foreign travel, were analysed by biotyping and molecular typing using pfge and multilocus variable-number tandem-repeat analysis (mlva); their antimicrobial susceptibilities were also evaluated. the isolates were from 26 countries, most of which were asian. molecular typing revealed a correlation among the genotypes, biotyp ...200919589900
an integrative approach combining noncovalent mass spectrometry, enzyme kinetics and x-ray crystallography to decipher tgt protein-protein and protein-rna interaction.the trna-modifying enzyme trna-guanine transglycosylase (tgt) is a putative target for new selective antibiotics against shigella bacteria. the formation of a tgt homodimer was suggested on the basis of several crystal structures of tgt in complex with rna. in the present study, noncovalent mass spectrometry was used (i) to confirm the dimeric oligomerization state of tgt in solution and (ii) to evidence the binding stoichiometry of the complex formed between tgt and its full-length substrate tr ...200919627989
[a multicentre study of shigella spp in henan province, during 2000-2007]. 200919565889
comparative study of pathogenicity tests for shigella spp. and enteroinvasive escherichia coli strains.the purpose of this study was to optimize an in vitro pathogenicity model, as an alternative to sereny test (on guinea pigs). the study was performed on 13 shigella spp. and 3 enteroinvasive escherichia coli (eiec) strains isolated in romania between 2005 and 2007. the investigation implied the comparative evaluation between the sereny test and cravioto's adapted method for the assessment of the adherence and invasion capacity of the studied bacterial strains on hela cells, as well as the pcr de ...200919507627
unc119 protects from shigella infection by inhibiting the abl family kinases.bacteria engage cell surface receptors and intracellular signaling molecules to enter the cell. unc119 is an adaptor protein, which interacts with receptors and tyrosine kinases. its role in bacterial invasion of cells is unknown.200919381274
role of azithromycin against clinical isolates of family enterobacteriaceae: a comparison of its minimum inhibitory concentration by three different methods.to determine the effect of azithromycin, a new azalide antibiotic, on clinical isolates of the family enterobacteriaceae and to determine and compare its minimum inhibitory concentration (mic) by disk diffusion, agar dilution and e-test methods.200919384031
bacterial type iii effectors inhibit cell lifting by targeting integrin-linked kinase.many pathogenic bacteria are able to surmount exfoliation and colonize the host epithelium efficiently. in a recent article in nature, kim et al. (2009) show that shigella flexneri ospe, a conserved type iii effector, reinforces host cell adherence and prevents detachment of the infected cells by interacting with integrin-linked kinase.200919527878
antimicrobial activity of endemic digitalis lamarckii ivan from turkey.antimicrobial activity of the methanolic extracts of leaves and flowers of d. lamarckii ivan, (scophulariaceae), an endemic plant species of turkey, was tested on ten bacterial and four yeast strains. effective antibacterial activity was observed in four bacterial strains. minimum inhibitory concentration (mic) was calculated by use of liquid culture tests and in all the four effective bacterial strains, the mic was found to be > or = 199.5 mg/ml. the minimum bactericidal concentration (mbc) of ...200919405389
molecular typing methodologies for microbial source tracking and epidemiological investigations of gram-negative bacterial foodborne pathogens.gram-negative bacterial foodborne pathogens are a worldwide cause of morbidity and mortality. the ability to carry out epidemiological investigations to determine the primary sources of bacterial contamination is important to improve public health. multiple methods are available for bacterial source tracking and to determine the distribution of pathogens isolated from sick patients. the molecular based typing methods available fall into three general categories: those based on restriction analys ...200919460308
estimated burden of human salmonella, shigella, and brucella infections in jordan, 2003-2004.there is limited information on the disease burden due to foodborne pathogens in the eastern mediterranean region. this study estimates the burden of disease in jordan for salmonella, shigella, and brucella during 1 year.200919415972
altered expression of inflammatory cytokine receptors in response to lps challenge through interaction between intestinal epithelial cells and lymphocytes of peyer's patch.the intense innate immunological activities occurring at the enteric mucosal surface involve interactions between intestinal epithelial cells and immune cells. our previous studies have indicated that peyer's patch lymphocytes may modulate intestinal epithelial barrier and ion transport function in homeostasis and host defense via cell-cell contact as well as cytokine signaling. the present study was undertaken using the established co-culture system of caco-2 epithelial cells with lymphocytes o ...200919385035
rapidly fatal bacteremia caused by shigella sonnei without preceding gastrointestinal symptoms in an adult patient with lung cancer. 200919416029
rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method.to develop a new, rapid and accurate reverse dot blot (rdb) method for the detection of intestinal pathogens in fecal samples.200919469006
synthesis, spectral characterization, in-vitro microbiological evaluation and cytotoxic activities of novel macrocyclic bis hydrazone.a macrocyclic hydrazone schiff base was synthesized by reacting 1,4-dicarbonyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol and a series of metal complexes with this new schiff base were synthesized by reaction with co(ii), ni(ii) and cu(ii) metal salts. the schiff base and its complexes have been characterized by elemental analyses, ir, (1)h nmr, uv-vis, fab mass, esr spectra, fluorescence, thermal, magnetic and molar conductance data. the analytical data reveal that the co(ii), ni(ii) ...200919419802
go4genome: a prokaryotic phylogeny based on genome organization.determining the phylogeny of closely related prokaryotes may fail in an analysis of rrna or a small set of sequences. whole-genome phylogeny utilizes the maximally available sample space. for a precise determination of genome similarity, two aspects have to be considered when developing an algorithm of whole-genome phylogeny: (1) gene order conservation is a more precise signal than gene content; and (2) when using sequence similarity, failures in identifying orthologues or the in situ replaceme ...200919436929
antimicrobial activity of the methanolic extract and compounds from morus mesozygia stem bark.this study was aimed at investigating the antimicrobial activity of the methanolic extract (mmb) and compounds isolated from the stem bark of morus mesozygia, namely 3beta-acetoxyurs-12-en-11-one (1), moracin q (2), moracin t (3), artocarpesin (4), cycloartocarpesin (5), moracin r (6), moracin u (8), moracin c (9), and moracin m (10).200919450674
diagnosis and treatment of acute or persistent diarrhea.studies of microbial pathogens and the toxins they produce are important for determining the mechanisms by which they cause disease and spread throughout a population. some bacteria produce secretory enterotoxins (such as cholera toxin or the heat-labile or stable enterotoxins produced by escherichia coli) that invade cells directly. others invade cells or produce cytotoxins (such as those produced by shigella, enteroinvasive e coli, or clostridium difficile) that damage cells or trigger host re ...200919457416
evaluation of antibacterial activity, phenol and flavonoid contents of thespesia populnea flower extracts.flavonoids which were reported as having many pharmacological activities, antimicrobial, antioxidant, cytotoxic, chemoprevention activities and they possess strong antiproliferative effects related to inhibition of cell cycle progression and apoptosis induction. on the basis of this thespesia populnea (l.) sol. ex correa (family-malvaceae) was selected and it is having the major composition of flavonoids and the antibacterial activity of methanolic extract of thespesia populnea flowers was inves ...200919553175
imported fresh sugar peas as suspected source of an outbreak of shigella sonnei in denmark, april-may 2009.we report on an outbreak of shigella sonnei infections involving ten cases notified through the laboratory surveillance system in denmark in april and may. the likely source was consumption of fresh, raw sugar peas (sugar snaps) imported from africa. this conclusion was based on interviews with cases and on the occurrence of a similar outbreak one month later in norway. fresh imported produce may occasionally be contaminated with pathogenic bacteria even when sold as ready-to-eat.200919555602
shigella sonnei infections in norway associated with sugar peas, may-june 2009.in may 2009, the norwegian institute of public health (niph) identified a possible outbreak of shigella sonnei infection involving four cases. additionally, five suspected cases in two separate households were reported. inspectors from the norwegian food safety authority (nfsa) visited the two households and found an unopened package of sugar peas imported from kenya in one of the households. one sample from the sugar peas was positive for shigella sonnei by two pcr methods. based on this result ...200919555603
the cellular level of o-antigen polymerase wzy determines chain length regulation by wzzb and wzzphs-2 in shigella flexneri 2a.the lipopolysaccharide o antigen of shigella flexneri 2a has two preferred chain lengths, a short (s-oag) composed of an average of 17 repeated units and a very long (vl-oag) of about 90 repeated units. these chain length distributions are controlled by the chromosomally encoded wzzb and the plasmid-encoded wzz(phs-2) proteins, respectively. in this study, genes wzzb, wzz(phs-2) and wzy (encoding the o-antigen polymerase) were cloned under the control of arabinose- and rhamnose-inducible promote ...200919556292
rational design and immunogenicity of liposome-based diepitope constructs: application to synthetic oligosaccharides mimicking the shigella flexneri 2a o-antigen.we have designed chemically defined diepitope constructs consisting of liposomes displaying at their surface synthetic oligosaccharides mimicking the o-antigen of the shigella flexneri 2a lipopolysaccharide (b-cell epitope) and influenza hemagglutinin peptide ha 307-319 (th epitope). using well controlled and high-yielding covalent bioconjugation reactions, the two structurally independent epitopes were coupled to the lipopeptide pam(3)cag, i.e. a tlr2 ligand known for its adjuvant properties, a ...200919559116
a randomized controlled trial to evaluate the efficacy of lactobacillus gg in infantile diarrhea.in a randomized, double-blind, placebo-controlled trial, 229 infants hospitalized for acute diarrhea in rural india were given a 10-day course of lactobacillus rhammosus gg (minimum dose, 10 degrees bacteria) or placebo. there was no difference in groups in the duration of diarrhea or numbers of stool on days 3, 6, or 10 of treatment.200919559297
involvement of rna-binding protein hfq in the osmotic-response regulation of inve gene expression in shigella sonnei.the expression of type iii secretion system (ttss) in shigella is regulated in response to changes in environmental osmolarity and temperature. temperature-dependent regulation of virf, the master regulator of ttss synthesis, is believed to occur at the transcriptional level. we recently demonstrated, however, that ttss synthesis also involves post-transcriptional regulation of the synthesis of inve, a target of virf and key regulator of ttss synthesis. the mrna levels of inve (virb) are stable ...200919476612
reactive arthritis: clinical aspects and medical management.reactive arthritis (rea) is an inflammatory arthritis that arises after certain gastrointestinal or genitourinary infections, representing a classic interplay between host and environment. it belongs to the group of arthritidies known as the spondyloarthropathies. the classic syndrome is a triad of symptoms, including the urethra, conjunctiva, and synovium; however, the majority of patients do not present with this triad. diagnostic criteria for rea exist, but data suggest new criteria are neede ...200919480995
ectopic production of vapcs from enterobacteria inhibits translation and trans-activates yoeb mrna interferase.toxin-antitoxin loci have been identified in almost all free-living prokaryotes, often in high copy numbers. the biological function and molecular targets of the abundant vapbc loci are not yet known. here we analyse the vapbc loci of salmonella lt2 and shigella plasmid pmysh6000. both loci encode putative pin (pilt n-terminal) domain toxins, and antitoxins that may regulate vapbc transcription. we show that vapbc(lt2) and vapbc(pmysh) are bona fide ta loci: (i) both vapcs inhibited cell growth ...200919400780
listeria monocytogenes membrane trafficking and lifestyle: the exception or the rule?listeria monocytogenes is an intracellular bacterial pathogen that promotes its internalization within nonprofessional phagocytes by interacting with specific host cell receptors. l. monocytogenes resides transiently in a membrane-bound compartment before escaping into the host cell cytosol where bacterial proliferation takes place. actin-based motility then promotes cell-to-cell pathogen spread. extensive studies on cytoskeleton rearrangements, membrane trafficking, and other events have establ ...200919575658
ptdins5p protects akt from dephosphorylation through pp2a inhibition.phosphatidylinositol 5-phosphate (ptdins5p), the most recently discovered phosphoinositide, has been proposed to play a role as a lipid mediator of intracellular signaling. we have previously shown that ptdins5p generated by ipgd, an effector of the causative agent of dysentery shigella flexneri, activates the pi 3-kinase/akt pathway. here, we demonstrate that ptdins5p is able to protect akt from dephosphorylation. this effect is not due to inhibition of the phosphoinositide phosphatase regulati ...200919576174
comparison of acute bloody and watery diarrhea: a case control study.the clinical and laboratory findings of 290 cases of bloody diarrhea who presented to the department of diarrhea training and treatment between june 1998 and may 2002 were investigated, and compared to those of two consecutive cases who had watery diarrhea. the bloody diarrhea group had higher mean age, higher frequencies of diarrhea, lower frequencies of vomiting, and shorter durations of diarrhea at the time of admission as compared to the watery diarrhea group. the number of cases using antib ...200919480324
global etiology of travelers' diarrhea: systematic review from 1973 to the present.fifty-one published studies of travelers' diarrhea (td) were examined to look for regional differences in pathogens identified. enterotoxigenic e. coli was detected in 1,678/5,518 (30.4%) of td cases overall, with rates in latin america/caribbean (l. america), africa, south asia, and southeast asia of 1,109/3,302 (33.6%), 389/1,217 (31.2%), 153/499 (30.6%), and 36/500 (7.2%), respectively (p < 0.001). enteroaggregative e. coli was the second most common agent in l. america, found in 166/689 (24. ...200919346386
synthesis, characterization, and immunogenicity in mice of shigella sonnei o-specific oligosaccharide-core-protein conjugates.shigellosis, an enteric disease, is on the world health organization's priority prevention list. in one study, the shigella sonnei o-specific polysaccharide (o-sp)-protein conjugate showed 72% protection against disease in israeli army recruits exposed to high rates (8-14%) of infection. the protection was related to vaccine-induced igg anti-o-sp levels. synthetic oligosaccharides of shigella dysenteriae type 1, bound by their reducing ends to a carrier protein ("sun"-type configuration), induce ...200919346477
laboratory-acquired infections.laboratory-acquired infections due to a wide variety of bacteria, viruses, fungi, and parasites have been described. although the precise risk of infection after an exposure remains poorly defined, surveys of laboratory-acquired infections suggest that brucella species, shigella species, salmonella species, mycobacterium tuberculosis, and neisseria meningitidis are the most common causes. infections due to the bloodborne pathogens (hepatitis b virus, hepatitis c virus, and human immunodeficiency ...200919480580
[norovirus infection in general hospitals for adults].to determine the role of noroviruses in the rise of hospital outbreaks of acute intestinal infections (aii), to study clinical and epidemiological aspects of hospital noroviral infection.200919514424
pulsed-field gel electrophoresis for molecular epidemiology of food pathogens.foodborne diseases due to well-recognized pathogens have emerged as an important and growing public health problem with a significant impact on health. molecular methods for subtyping these microorganisms have become a valid adjunct to the traditional techniques employed in most laboratories. one such molecular technique for the detection and identification of food pathogens is pulsed-field gel electrophoresis (pfge). this method separates large dna molecules by the use of an alternating electri ...200919521867
analytical comparison of nine pcr primer sets designed to detect the presence of escherichia coli/shigella in water samples.the analytical performance of 9 different pcr primer sets designed to detect escherichia coli and shigella in water has been evaluated in terms of ubiquity, specificity, and analytical detection limit. of the 9 pcr primer sets tested, only 3 of the 5 primer sets targeting uida gene and the primer set targeting tuf gene amplified dna from all e. coli strains tested. however, of those 4 primer sets, only the primer set targeting the tuf gene also amplified dna from all shigella strains tested. for ...200919482328
bulging fontanelle in febrile infants: is lumbar puncture mandatory?to determine the aetiologies and clinical characteristics of infants with fever and a bulging fontanelle.200919531528
determination of emitted airborne microorganisms from a bio-pak wastewater treatment plant.results of a study conducted to assess the degree of airborne microbial contamination generated by a wastewater treatment plant (wwtp) with bioreactor "bio-pak" closed treatment system and evaluation of the dispersion of potential pathogens are described. over the year aerosol samples were collected simultaneously with sedimentation and impact methods from several plant sites and the surroundings. external upwind sites were used as control. total colony-forming counts of heterotrophic psychrophi ...200919428042
determination of foodborne pathogenic bacteria by multiplex pcr-microchip capillary electrophoresis with genetic algorithm-support vector regression optimization.a rapid and sensitive method based on microchip capillary electrophoresis with condition optimization of genetic algorithm-support vector regression (ga-svr) was developed and applied to simultaneous analysis of multiplex pcr products of four foodborne pathogenic bacteria. four pairs of oligonucleotide primers were designed to exclusively amplify the targeted gene of vibrio parahemolyticus, salmonella, escherichia coli (e. coli) o157:h7, shigella and the quadruplex pcr parameters were optimized. ...200919446070
inactivation of salmonella enteritidis in chicken breast fillets by single-cycle and multiple-cycle high pressure treatments.the effect of single-cycle and multiple-cycle high hydrostatic pressure (hhp) treatments on the survival of three salmonella enteritidis strains in chicken breast fillets was investigated. the surface of fillets was inoculated with a cocktail of three salmonella strains at approximately 10(7) colony-forming units (cfu)/g, and held at 4 degrees c for 20 hours before hhp treatments. reduction of salmonella counts on tryptic soy agar (tsa) by single-cycle treatments at 300 mpa and 12 degrees c rang ...200919388832
improvement of an acid phosphatase/dhap-dependent aldolase cascade reaction by using directed evolution.to enhance the phosphorylating activity of the bacterial nonspecific acid phosphatase from salmonella enterica ser. typhimurium lt2 towards dihydroxyacetone (dha), a mutant library was generated from the native enzyme. three different variants that showed enhanced activity were identified after one round of eppcr. the single mutant v78l was the most active and showed an increase in the maximal dhap concentration to 25 % higher than that of the wild-type enzyme at ph 6.0. this variant is 17 times ...200919623595
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