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close relation of the o-polysaccharide structure of escherichia coli o168 and revised structure of the o-polysaccharide of shigella dysenteriae type 4.the o-polysaccharide was isolated from the lipopolysaccharide of escherichia coli o168 and studied by chemical analyses and smith degradation along with (1)h and (13)c nmr spectroscopies. the following structure of the branched pentasaccharide repeating unit of the o-polysaccharide was established: [carbohydrate structure: see text] where 6-o-acetylation of glcnac is partial. reinvestigation of the o-polysaccharide of shigella dysenteriae type 4 established earlier showed it to have the same str ...200717880932
multilocus variable-number tandem-repeat analysis for molecular typing of shigella sonnei.a multilocus variable-number tandem-repeat (vntr) analysis (mlva) method was developed and evaluated for the subtyping of shigella sonnei isolates. a total of 26 vntr loci were identified by exploring the repeat sequence loci in the genomic sequences of s. sonnei strains ss046 and 53g and by testing 536 isolates that had previously been characterized by pulsed-field gel electrophoresis (pfge). the discriminatory power of mlva (simpson's index of diversity [d], 0.9524; 95% confidence interval [ci ...200717881552
plasmid-mediated quinolone resistance conferred by qnrs1 in salmonella enterica serovar virchow isolated from turkish food of avian origin.to study the molecular characteristics of the quinolone and associated ampicillin resistance mechanisms present in salmonella enterica serovar virchow isolated from turkish foods.200717881633
a case of shigellosis with intractable septic shock and convulsions.although shigellosis is a potentially fatal disease that may cause a number of extra-intestinal manifestations, intractable septic shock is an unusual complication. here we describe a 6-month-old infant who developed severe septic shock and convulsions during an episode of dysentery caused by multidrug-resistant shigella dysenteriae. the case presentation demonstrates how shigellosis can lead to rare and potentially misleading complications such as septic shock when not treated adequately and pr ...200717881877
in vitro antimicrobial activity of rifaximin against enteropathogens causing traveler's diarrhea.the in vitro activity of rifaximin against 84 diarrheagenic escherichia coli and 11 shigella sonnei causing traveler's diarrhea was evaluated. the mic of rifaximin ranged between <0.007 and 32 mg/l; other agents tested had an mic of >256 mg/l in most cases. the results showed the potential use of rifaximin to treat these infections.200717889485
[modulation of virulence expression in escherichia coli and shigella spp. by environmental factors]. 200717891998
dynamic proteome changes of shigella flexneri 2a during transition from exponential growth to stationary phase.shigella flexneri is an infectious pathogen that causes dysentery to human, which remains a serious threat to public health, particularly in developing countries. in this study, the global protein expression patterns of s. flexneri during transition from exponential growth to stationary phase in vitro were analyzed by using 2-d page combined with maldi-tof ms. in a time-course experiment with five time points, the relative abundance of 49 protein spots varied significantly. interestingly, a puta ...200717893076
the type iii secretion system of proteus mirabilis hi4320 does not contribute to virulence in the mouse model of ascending urinary tract infection.the gram-negative enteric bacterium proteus mirabilis is a frequent cause of urinary tract infections (utis) in individuals with long-term indwelling catheters or with complicated urinary tracts. the recent release of the p. mirabilis strain hi4320 genome sequence has facilitated identification of potential virulence factors in this organism. genes appearing to encode a type iii secretion system (ttss) were found in a low gc-content pathogenicity island in the p. mirabilis chromosome. this islan ...200717893161
molecular characterization of antimicrobial compound produced by lactobacillus acidophilus aa11.approximately 63 strains of lactobacillus acidophilus were isolated from egyptian home-made cheese and examined for production of antagonism. only eight strains demonstrated inhibitory activity against spoilage microorganisms (i.e. staphylococcus aureus and bacillus cereus) and pathogens (i.e. e. coli, salmonella sp. and shigella sp.). lactobacillus acidophilus aa11 produced higher antimicrobial activity with a wide range of inhibition. the agent aa11 was sensitive to proteolytic enzymes and ret ...200717899791
an outbreak of multi-resistant shigella sonnei in australia: possible link to the outbreak of shigellosis in denmark associated with imported baby corn from thailand. 200717900420
explaining unexplained diarrhea and associating risks and infections.gastrointestinal illnesses are common afflictions. however, knowledge of their etiology is often lacking. moreover, most cases of infections with reportable enteric pathogens (campylobacter jejuni, escherichia coli o157:h7, salmonella, shigella, yersinia, cryptosporidia and giardia) have sporadic modes of acquisition, yet control measures are often biased towards mitigation of risks discerned by outbreak analysis. to determine the etiology of unexplained diarrhea it is important to study populat ...200717692144
[ekiri syndrome complicating shigellosis]. 200717692219
[intrafamilial outbreak of shigella flexneri gastroenteritis in madrid]. 200717692266
use of the tna operon as a new molecular target for escherichia coli detection.a quantitative real-time pcr targeting the tnaa gene was studied to detect escherichia coli and distinguish e. coli from shigella spp. these microorganisms revealed high similarity in the molecular organization of the tna operon.200717693560
differential regulation of caspase-1 activation, pyroptosis, and autophagy via ipaf and asc in shigella-infected macrophages.shigella infection, the cause of bacillary dysentery, induces caspase-1 activation and cell death in macrophages, but the precise mechanisms of this activation remain poorly understood. we demonstrate here that caspase-1 activation and il-1beta processing induced by shigella are mediated through ipaf, a cytosolic pattern-recognition receptor of the nucleotide-binding oligomerization domain (nod)-like receptor (nlr) family, and the adaptor protein apoptosis-associated speck-like protein containin ...200717696608
effect of lactobacillus rhamnosus gg in persistent diarrhea in indian children: a randomized controlled trial.to evaluate the role of lactobacillus rhamnosus gg (lgg) as probiotic in persistent diarrhea (pd) in children of north bengal, india.200717700424
antimicrobial and antioxidant properties of rosemary and sage (rosmarinus officinalis l. and salvia officinalis l., lamiaceae) essential oils.the essential oils of rosemary ( rosmarinus officinalis l.) and sage ( salvia officinalis l.) were analyzed by means of gas chromatography-mass spectrometry and assayed for their antimicrobial and antioxidant activities. antimicrobial activity was tested against 13 bacterial strains and 6 fungi, including candida albicans and 5 dermatomycetes. the most important antibacterial activity of both essential oils was expressed on escherichia coli, salmonella typhi, s. enteritidis, and shigella sonei. ...200717708648
brucella abortus requires the heme transporter bhua for maintenance of chronic infection in balb/c mice.the gene annotated bab2_1150 in the brucella abortus 2308 genome sequence is predicted to encode a homolog of the well-characterized heme transporter shua of shigella dysenteriae and accordingly has been given the designation bhua (brucella heme utilization). phenotypic analysis of an isogenic bhua mutant derived from b. abortus 2308 verified that there is a link between bhua and the ability of the parent strain to use heme as an iron source in in vitro assays. maximum expression of bhua in b. a ...200717709407
omptin proteins: an expanding family of outer membrane proteases in gram-negative enterobacteriaceae.the escherichia coli k-12 outer membrane protein ompt is a prototype of a unique family of bacterial endopeptidases known as the omptins. this family includes ompt and ompp of e. coli, sopa of shigella flexneri, pgte of salmonella enterica, and pla of yersinia pestis. despite their sequence similarities, the omptins vary in their reported functions. the ompt protease is characterized by narrow cleavage specificity defined by the extracellular loops of the beta-barrel protruding above the lipid b ...200717710644
first detection and sequence analysis of the bla-ctx-m-15 gene in lebanese isolates of extended-spectrum-beta-lactamase-producing shigella sonnei.the emergence in shigella species of extended-spectrum beta-lactamases (esbl) that impart resistance to third-generation cephalosporins is a growing concern world-wide. so far, however, esbl-producing shigella have only been reported seven times, albeit from seven different countries. in lebanon, three esbl-producing clinical isolates of s. sonnei were recovered from 30 cases of shigellosis diagnosed between july 2004 and october 2005. all three were found to be resistant to amoxycillin, cefotax ...200717716434
a bacterial effector targets mad2l2, an apc inhibitor, to modulate host cell cycling.the gut epithelium self-renews every several days, providing an important innate defense system that limits bacterial colonization. nevertheless, many bacterial pathogens, including shigella, efficiently colonize the intestinal epithelium. here, we show that the shigella effector ipab, when delivered into epithelial cells, causes cell-cycle arrest by targeting mad2l2, an anaphase-promoting complex/cyclosome (apc) inhibitor. cyclin b1 ubiquitination assays revealed that apc undergoes unscheduled ...200717719540
spontaneous zygogenesis, a wide-ranging mating process in bacteria.spontaneous zygogenesis (or z-mating) in escherichia coli, unlike f-mediated conjugation, promotes formation of complete zygotes. most z-mating products have proven to be phenotypically unstable, losing part of the phenotype for which they were selected. persistent z-mating products appear as stable genetic recombinants or yield subclones of two types: either both parental types or one of them plus a recombinant type, and the ability to promote spontaneous zygogenesis can appear in all emerging ...200717720456
bacterial, fungal and parasitic contamination of cockroaches in public hospitals of hamadan, iran.to determine the possible role of cockroaches in dissemination of medically important microorganisms, a study was carried out in public hospitals and residential areas of hamadan city, west of iran. bacteria, fungi and parasites of medical importance were isolated and identified. the total number of blattella germanica collected from hospitals were 133 as the case group. the cockroaches collected from residential areas were 45 as the control group.200717722863
effect of the nonreducing end of shigella dysenteriae type 1 o-specific oligosaccharides on their immunogenicity as conjugates in mice.endemic and epidemic shigellosis, an acute invasive disease of the lower intestines, afflicts millions of people worldwide with an estimated one million fatalities per annum at a low infectious dose. our approach to vaccine development against shigella is based on the hypothesis that serum igg antibodies to the o-specific polysaccharide (o-sp) domains of the lps of these organisms confer protection to infection. the synthetic oligosaccharides corresponding to the tetrasaccharide repeating unit o ...200717726093
an inducible lambdoid prophage encoding cytolethal distending toxin (cdt-i) and a type iii effector protein in enteropathogenic escherichia coli.cytolethal distending toxins (cdts) are inhibitory cyclomodulins, which block eukaryotic cell proliferation and are produced by a diverse group of gram-negative bacteria, including escherichia coli strains associated with intestinal and extraintestinal infections. however, the mode of transmission of the toxin gene clusters among diverse bacterial pathogens is unclear. we found that cdt-i produced by enteropathogenic e. coli strains associated with diarrhea is encoded by a lambdoid prophage, whi ...200717726095
the significance of the number of submitted samples and patient-related factors for faecal bacterial diagnostics.the sensitivity of bacteriological testing of faecal samples from patients with diarrhoea has not been properly determined. the present study analysed the association between the results of stool sample examinations and the number of samples examined per patient and other patient-related factors. data concerning faecal specimens referred for culture for enteric bacterial pathogens (campylobacter, salmonella, shigella and yersinia) to the central microbiological laboratory in denmark between 1995 ...200717727686
role of u.s. military research programs in the development of u.s.-licensed vaccines for naturally occurring infectious diseases.u.s. military physicians and researchers have collaborated in the development of eight u.s.-licensed vaccines since 1934, when product efficacy requirements were added to product safety requirements mandated in 1902. these vaccines include influenza (1945), rubella (1969), adenovirus types 4 and 7 (1980), meningococcus a, c, y, w-135 (1981), hepatitis b (1981), oral typhoid (1989), japanese encephalitis (1992), and hepatitis a (1995). current efforts include new adenovirus and japanese encephali ...200717728025
detection of ctx-m-14 extended-spectrum beta-lactamase in shigella sonnei isolates from china.shigellosis is an important cause of acute diarrheal disease and multidrug-resistant phenotype has been reported in s. sonnei. in this study, we investigate the resistance and identify extended-spectrum beta-lactamases (esbls) gene in 37 s. sonnei isolates by agar dilution procedure and the modified three-dimensional test, respectively. the bla genes of esbl-producing isolates were detected by polymerase chain reaction (pcr) and sequencing. more than 50% of these strains were resistant to tetrac ...200717767959
intracellular type iii secretion by cytoplasmic shigella flexneri promotes caspase-1-dependent macrophage cell death.the gram-negative bacterium shigella flexneri triggers pro-inflammatory apoptotic cell death in macrophages, which is crucial for the onset of an acute inflammatory diarrhoea termed bacillary dysentery. the mxi-spa type iii secretion system promotes bacterial uptake and escape into the cytoplasm, where, dependent on the translocator/effector protein ipab, caspase-1 [interleukin (il)-1beta-converting enzyme] and its substrate il-1beta are activated. here, we show that in the course of a macrophag ...200717768231
two or more enteropathogens are associated with diarrhoea in mexican children.diarrhoeal diseases constitute a major public health problem, particularly in the developing world, where the rate of mortality and morbidity is very high. the purpose of this study was to conduct a 2 years and 3 months study in order to determine the prevalence of five enteropathogen diarrheogenic agents in mexico city.200718162140
effects of a human milk-derived human milk fortifier on the antibacterial actions of human milk.to compare the effects of a human breastmilk-derived fortifier on the antibacterial activity of milk obtained from lactating mothers delivering prematurely with the effects of a powdered fortifier on the same milk.200718081457
microbial survey of selected ontario-grown fresh fruits and vegetables.recent produce-related outbreaks have been receiving heightened media coverage, which has increased public concern toward the safety of fresh fruits and vegetables. in response, the microbial contamination of ontario-grown fresh fruits and vegetables was evaluated by the ontario ministry of agriculture, food and rural affairs during the summer of 2004. prior to this survey, information specific to the microbial contamination of ontario-produced fruits and vegetables was limited. this nonregulato ...200718095445
effect of hand wash agents on controlling the transmission of pathogenic bacteria from hands to food.the goals of this study were to evaluate the effectiveness of two hand wash regimens in reducing transient bacteria on the skin following a single hand wash and the subsequent transfer of the bacteria to a ready-to-eat food item, freshly cut cantaloupe melon. the number of bacteria recovered from hands and the quantity transferred to the melon were significantly less following the use of an antibacterial soap compared with plain soap. the antimicrobial soap achieved > 3-log reductions versus esc ...200718095447
structural insights into the enzymatic mechanism of the pathogenic mapk phosphothreonine lyase.the ospf family of phosphothreonine lyase, including spvc from salmonella, irreversibly inactivates the dual-phosphorylated host mapks (pt-x-py) through beta elimination. we determined crystal structures of spvc and its complex with a phosphopeptide substrate. spvc adopts a unique fold of alpha/beta type. the disordered n terminus harbors a canonical d motif for mapk substrate docking. the enzyme-substrate complex structure indicates that recognition of the phosphotyrosine followed by insertion ...200718060821
[expression profile analysis of host hela cells invasived by shigella flexneri 2a].the changes of genes expression in hela cell during the invasion with shigella species for 1h and 3h were analyzed by cdna microarrays. the data showed that the expression levels of 752 genes were altered twice or greater as compared with the control 509 of them were up-regulated, and 306 were down-regulated. it was supposed that some signal pathways in hela cell were activated, then many genes were induced, and at last comprehensive cell responses were produced, so that hela cell could prevent ...200718062254
[construction of prophylactic recombinant hpv58-attenuated shigella vector live vaccine and evaluation of its protective efficacy and immunogenicity in the guinea pig keratoconjunctivitis model].to construct the prophylactic recombinant hpv58-attenuated shigella vector live vaccine and evaluate its protective efficacy and immunogenicity in the guinea pig keratoconjunctivitis model.200718062891
[identification of closely related bacteria via phylogenetic methods].to differentiate closely related pathogenic bacteria via phylogenetic method on the basis of gyrb gene sequences.200718067224
antimicrobial susceptibility of shigella flexneri and s. dysenteriae isolated from stool specimens of patients with bloody diarrhoea in mwanza, tanzania.this study was conducted to determine frequency and pattern of antimicrobial susceptibility of shigella species isolated from stool specimens collected from patients presenting with bloody diarrhoea in mwanza city, tanzania. the study was carried out from october 2004 to october 2005 and involved patients attending sekou toure regional hospital and butimba health centre. bacteriological cultures were done at the national institute for medical research laboratory. a total of 489 patients (median ...200718087897
characterization of probiotic escherichia coli isolates with a novel pan-genome microarray.microarrays have recently emerged as a novel procedure to evaluate the genetic content of bacterial species. so far, microarrays have mostly covered single or few strains from the same species. however, with cheaper high-throughput sequencing techniques emerging, multiple strains of the same species are rapidly becoming available, allowing for the definition and characterization of a whole species as a population of genomes--the 'pan-genome'.200718088402
antibacterial activity directed isolation of compounds from punica granatum.chemical investigation of the methanolic extract of pomegranate fruit following antibacterial activity directed isolation led to the isolation of pelargonidin-3-galactose, cyanidin-3-glucose, gallic acid, quercetin, and myricetin. all these compounds exhibited substantial activity against species of corynebacteria, staphylococci, streptococci, bacillus subtilis, shigella, salmonella, vibrio cholera, and escherichia coli. however, all these compounds were more active against gram-positive species ...200718034726
synthesis and evaluation of the antimicrobial activity of novel quinazolinones.a simple and efficient microwave-assisted methodology for regioselective alkylation of exocyclic nitrogen of cyclic amidines was developed and novel n-alkylated 3,4-dihydropyrazino [2,1-b] quinazolin-6-ones were prepared. although none of the molecules tested have any specific anti-quorum sensing (-qs) activity, our result validates the growth tests devised to control the bias of the anti-qs tests. among the molecules studied, compound 2b exhibits interesting activity against the gram-negative b ...200718035826
[characteristic of the etiologic structure of acute enteric infections in adults based on the data from infectious diseases hospital].study of the etiologic spectrum of sporadic cases of causative agents of acute enteric infections (aei) in 753 patients aged 15-85 years old using polymerase chain reaction (pcr) was performed in the infectious diseases hospital during 12 months. it was shown that detection of the causative agents of aei by pcr was 2.2 times more effective than routine microbiologic diagnostics supplemented with test of feces on rotavirus by elisa method and allowed to detect etiologic agent in 54.3% of the pati ...200718038539
changing patterns of antimicrobial susceptibility of shigella serotypes isolated from children with acute diarrhea in manipal, south india, a 5 year study.this study was carried out to determine the current pattern of shigella serogroups and their antimicrobial resistance in children with acute gastroenteritis in manipal, south india. a total of 1,200 stool samples were collected from april 2001 to may 2006 in children suffering from acute gastroenteritis attending the out-patient department of pediatrics at kasturba hospital, manipal, south india. these samples were cultured for enteric pathogens. the isolates were confirmed to be shigella by bio ...200718041303
environmental stress regulates shigella virulence: interplay between anerobiosis and iron acquisition. 200718041901
parenteral long-acting amoxicillin reduces intestinal bacterial community diversity in piglets even 5 weeks after the administration.we investigated the long-term effects of a single intramuscular administration of amoxicillin (15 mg kg(-1)) 1 day after birth, on piglet intestinal microbiota. animals received no creep feed before weaning on day 28 of age. for the next 11 days, the piglets received a wheat-barley-based diet. colon digesta samples were collected on day 39 and subjected to denaturing gradient gel electrophoresis (dgge) of pcr-amplified 16s rrna gene fragments. dgge fingerprint diversity indices differed between ...200718043627
culture independent analysis of ileal mucosa reveals a selective increase in invasive escherichia coli of novel phylogeny relative to depletion of clostridiales in crohn's disease involving the ileum.intestinal bacteria are implicated increasingly as a pivotal factor in the development of crohn's disease, but the specific components of the complex polymicrobial enteric environment driving the inflammatory response are unresolved. this study addresses the role of the ileal mucosa-associated microflora in crohn's disease. a combination of culture-independent analysis of bacterial diversity (16s rdna library analysis, quantitative pcr and fluorescence in situ hybridization) and molecular charac ...200718043660
[acute and prolonged infectious diarrheas, of microbial and viral etiology: methods of clinical and microbiological diagnosis].the authors relate clinical-microbiological criteria for a rational diagnosis of acute and prolonged enteritis, distinguishing between home and imported diarrheas. during 2005, 381 subjects (192 children and 189 adults) with acute diarrhea and 110 subjects (16 children and 94 adults) with prolonged diarrhea were examined. in the first group salmonella prevailed in 11.1% of cases (10.9% among children and 11.1% among adults); campylobacter in 9.2% (respectively 8.9% and 9.5%); other bacteria were ...200718044404
cloning, expression, purification, characterization, crystallization and x-ray diffraction of bifunctional pyrimidine deaminase/reductase from shigella flexneri 2a.bifunctional pyrimidine deaminase/reductase (ribd) plays an important role during riboflavin biosynthesis in many microorganisms. the 40.4 kda ribd from shigella flexneri 2a has been cloned, expressed, purified and characterized. three crystals of ribd have been obtained by the hanging-drop technique at 291 k using peg 20k or nacl as precipitant. the ribd crystal using peg 20k as precipitant diffracted to 2.5a.200718045236
shiga toxin induces tubular membrane invaginations for its uptake into cells.clathrin seems to be dispensable for some endocytic processes and, in several instances, no cytosolic coat protein complexes could be detected at sites of membrane invagination. hence, new principles must in these cases be invoked to account for the mechanical force driving membrane shape changes. here we show that the gb3 (glycolipid)-binding b-subunit of bacterial shiga toxin induces narrow tubular membrane invaginations in human and mouse cells and model membranes. in cells, tubule occurrence ...200718046403
comparing invasive and non-invasive of isolated shigella flexneri by electron microscopy of cell culture, sds-page and congo red method.the aim of this study was to compare invasive and non-invasive strains of shigella flexneri isolated from tehran by a 120 kda protein band by sds-page, electron microscopy of cell culture and congo red dye methods.200718051704
antibiotic resistance and resistance mechanisms in campylobacter jejuni and campylobacter coli.campylobacter jejuni and campylobacter coli are recognized as the most common causative agents of bacterial gastroenteritis in the world and infections with these organisms occur more frequently than do infections due to salmonella species, shigella species, or escherichia coli 0157:h7. the incidence of human campylobacter infections has increased markedly in both developed and developing countries worldwide and, more significantly, so has the rapid emergence of antibiotic-resistant campylobacte ...200718031331
the distribution of insertion sequences in the genome of shigella flexneri strain 2457t.shigella flexneri, which causes shigellosis in humans, evolved from escherichia coli. the sequencing of shigella genomes has revealed that a large number of insertion sequence (is) elements (over 200 elements) reside in the genome. although the presence of these elements has been noted previously and summarized, more detailed analyses are required to understand their evolutionary significance. here, the genome of s. flexneri strain 2457t is used to investigate the spatial distribution of is copi ...200718031340
secretory iga mediates bacterial translocation to dendritic cells in mouse peyer's patches with restriction to mucosal compartment.in addition to fulfilling its function of immune exclusion at mucosal surfaces, secretory iga (siga) ab exhibits the striking feature to adhere selectively to m cells in the mouse and human intestinal peyer's patches (pps). subsequent uptake drives the siga ab to dendritic cells (dcs), which become partially activated. using freshly isolated mouse dcs, we found that the interaction with siga was tissue and dc subtype dependent. only dcs isolated from pps and mesenteric lymph nodes interacted wit ...200718025221
type iii secretion effectors of the ipah family are e3 ubiquitin ligases.many bacteria pathogenic for plants or animals, including shigella spp., which is responsible for shigellosis in humans, use a type iii secretion apparatus to inject effector proteins into host cells. effectors alter cell signaling and host responses induced upon infection; however, their precise biochemical activities have been elucidated in very few cases. utilizing saccharomyces cerevisiae as a surrogate host, we show that the shigella effector ipah9.8 interrupts pheromone response signaling ...200718005683
microbial pathogen-induced necrotic cell death mediated by the inflammasome components cias1/cryopyrin/nlrp3 and asc.cryopyrin (cias1, nlrp3) and asc are components of the inflammasome, a multiprotein complex required for caspase-1 activation and cytokine il-1beta production. cias1 mutations underlie autoinflammation characterized by excessive il-1beta secretion. disease-associated cryopyrin also causes a program of necrosis-like cell death in macrophages, the mechanistic details of which are unknown. we find that patient monocytes carrying disease-associated cias1 mutations exhibit excessive necrosis-like dea ...200718005730
epidemiology and clinical presentation of shigellosis in children less than five years of age in rural mozambique.rectal swabs were collected from 1354 children <5 years of age with diarrhea attending manhiça district hospital and from 227 healthy community controls. shigellosis incidence was high among children aged 12-47 months (488.4/10(5) child-years at risk). fever and dysentery were prominent clinical findings. shigella was more frequently isolated from cases than controls (6.7% versus 0.4%, p = 0.004), and from dysentery than nondysenteric diarrhea (24.1% versus 3.5%, p < 0.001). shigella flexneri 2a ...200717984817
increasing spectrum in antimicrobial resistance of shigella isolates in bangladesh: resistance to azithromycin and ceftriaxone and decreased susceptibility to ciprofloxacin.antimicrobial resistance of shigella isolates in bangladesh, during 2001-2002, was studied and compared with that of 1991-1992 to identify the changes in resistance patterns and trends. a significant increase in resistance to trimethoprim-sulphamethoxazole (from 52% to 72%, p < 0.01) and nalidixic acid (from 19% to 51%, p < 0.01) was detected. high, but unchanged, resistance to tetracycline, ampicillin, and chloramphenicol, low resistance to mecillinam (resistance 3%, intermediate 3%), and to em ...200717985817
outbreaks of shigellosis in denmark and australia associated with imported baby corn, august 2007--final summary.the recently reported concurrent outbreaks of shigella sonnei infections in denmark and australia have been found to be linked to a common baby corn packing house in thailand via trace-back of the distribution chain. distribution records indicated that three additional countries received affected product from the implicated thai packing house during the period of potential contamination. these countries were notified through the world health organization's international food safety authorities n ...200717991373
cross-border investigation of a shigella sonnei outbreak in a group of norwegian tourists after a trip to russia.in early september 2006, the norwegian institute of public health was alerted to an outbreak of shigella sonnei infections (shigellosis) among 23 norwegian passengers who had taken a bus tour from kirkenes, norway to murmansk, russia. the trip lasted from 27 to 31 august, and the group stayed in various hotels and visited several restaurants in both kirkenes and murmansk during this period. stool samples from three ill passengers yielded s. sonnei; an additional 10 passengers had gastrointestina ...200717991389
acute gastrointestinal infection, respiratory illness, and noncombat injury among us military personnel during operation bright star 2005, in northern egypt.in the fall 2005, approximately 7,500 us military personnel participated in an exercise in the egyptian desert. the epidemiology of disease and noncombat injury among deployed troops is important in the context of assessing current mitigation strategies and the development of future ones.200717995535
inactivation of shigella boydii 18 idph and listeria monocytogenes scott a with power ultrasound at different acoustic energy densities and temperatures.the effect of acoustic energy density (aed) on inactivation of shigella boydii 18 idph and listeria monocytogenes scott a in a cell suspension was studied at sublethal temperatures and at aeds of 0.49, 0.85, and 1.43 w/ml. the effect of temperature on ultrasonic inactivation of l. monocytogenes scott a at 35, 50, and 65 degrees c was examined at an aed of 1.43 w/ml. increasing aed increased the rate of inactivation for both s. boydii and l. monocytogenes. the destruction of s. boydii and l. mono ...200717995776
acanthamoeba: could it be an environmental host of shigella?shigellosis is a serious public health problem in korea, because large outbreaks of shigella sonnei infections were recorded in many parts of the country during the period 1998-2000. however, the epidemiological features of shigellosis are not well known. in this study, we devised conditions suitable for the growth and replication of shigella in an amoebic intracellular environment, and investigate whether medium conditions affect the survival and replication of shigella within acanthamoeba. we ...200716978610
short report: analysis of clonal relationship among shigella sonnei isolates circulating in argentina.thirty-five isolates of shigella sonnei from patients with diarrhoea in three geographic regions of argentina were examined for genetic diversity by pulsed-field gel electrophoresis (pfge) and plasmid profile. pfge of xbai and blni dna digests confirmed the occurrence of outbreaks in two regions caused by two separate predominant clones of s. sonnei. the third region was characterized by three circulating clones, one of which was possibly associated with an outbreak. similar plasmids were found ...200716999876
screening antimicrobial activity of various extracts of artemisia dracunculus l.the antimicrobial activities of chloroform, acetone and two different concentrations of methanol extracts of artemisia dracunculus l. were studied. these extracts were tested against nine bacteria and four yeasts strains by the disc diffusion method. the results indicated that the methanol extract of a. dracunculus is more effective against tested microorganisms than chloroform or acetone extracts. the chloroform and acetone extracts were inhibitory only towards pseudomonas aeruginosa (atcc 2785 ...200716986171
bacteriocin-like inhibitor substances produced by mexican strains of bacillus thuringiensis.bacteriocins are antimicrobial peptides synthesized and secreted by bacteria and could potentially be used as natural food preservatives. here, we report the production of bacteriocin-like inhibitor substances (bt-blis) by five mexican strains of bacillus thuringiensis. bacillus thuringiensis subsp. morrisoni (lbit 269), b. thuringiensis subsp. kurstaki (lbit 287), b. thuringiensis subsp kenyae (lbit 404), b. thuringiensis subsp. entomocidus (lbit 420) and b. thuringiensis subsp. tolworthi (lbit ...200717031616
cholesterol is required to trigger caspase-1 activation and macrophage apoptosis after phagosomal escape of shigella.pro-inflammatory macrophage apoptosis is pivotal in the aetiology of bacillary dysentery, an acute inflammatory diarrhoea caused by shigella spp. s. flexneri triggers its uptake by macrophages, escapes the phagosome and kills the host cell by a cytotoxic pathway, which activates and requires caspase-1 [interleukin (il)-1beta-converting enzyme] and releases mature il-1beta. the bacterial type iii-secreted translocator/effector protein ipab triggers cell death and directly binds to caspase-1. here ...200716925787
structural organization of the needle complex of the type iii secretion apparatus of shigella flexneri.the secretion apparatus known as the needle complex (nc) from the bacterium shigella flexneri was studied by single particle electron microscopy. the isolated intact nc appears in projection to be composed of a basal body consisting of seven rings and a protruding needle appendage. a comparison of averaged projections of the intact nc and its fragments revealed the organization of the nc into several major subcomplexes. one of these lacks an inner membrane ring of the basal body but still presen ...200716920362
phylogenetic analysis of enteric species of the family enterobacteriaceae using the oric-locus.phylogenetic analysis of 38 enteric species belonging to the enterobacteraceae family was carried out using the non-coding locus oric, the chromosomal replication origin. the oric loci were amplified with conserved oligonucleotides and the pcr fragments were sequenced directly. the results establish a phylogenetic tree for the classification of different species of the genera escherichia, shigella, salmonella, enterobacter, citrobacter, klebsiella, raoultella, kluyvera, cedecea and buttiauxella. ...200716904857
villin severing activity enhances actin-based motility in vivo.villin, an actin-binding protein associated with the actin bundles that support microvilli, bundles, caps, nucleates, and severs actin in a calcium-dependant manner in vitro. we hypothesized that the severing activity of villin is responsible for its reported role in enhancing cell plasticity and motility. to test this hypothesis, we chose a loss of function strategy and introduced mutations in villin based on sequence comparison with capg. by pyrene-actin assays, we demonstrate that this mutant ...200717182858
structural and genetic evidence that the escherichia coli o148 o antigen is the precursor of the shigella dysenteriae type 1 o antigen and identification of a glucosyltransferase gene.shigella dysenteriae type 1 is the most virulent serotype of shigella. enterotoxigenic escherichia coli o148 is pathogenic and can cause diarrhoea. the following structure was established for the tetrasaccharide repeating unit of the e. coli o148 o antigen: -->3)-alpha-l-rhap-(1-->3)-alpha-l-rhap-(1-->2)-alpha-d-glcp-(1-->3)-alpha-d-glcpnac-(1-->. this differs from the structure reported earlier for s. dysenteriae type 1 by having a glucose (glc) residue in place of a galactose (gal) residue. th ...200717185542
gene cluster analysis method identifies horizontally transferred genes with high reliability and indicates that they provide the main mechanism of operon gain in 8 species of gamma-proteobacteria.the formation mechanism of operons remains unresolved: operons may form by rearrangements within a genome or by acquisition of genes from other species, that is, horizontal gene transfer (hgt). one hindrance to its elucidation is the unavailability of a method to accurately identify hgt, although it is generally considered to occur. it is critically important first to select horizontally transferred (ht) genes reliably and then to determine the extent to which hgt is involved in operon formation ...200717185745
serological cross-reactivity of environmental isolates of enterobacter, escherichia, stenotrophomonas, and aerococcus with shigella spp.-specific antisera.using protocols designed for the isolation of shigella from environmental freshwater samples from different regions of bangladesh, 11 bacterial strains giving rise to shigella-like colonies on selective agar plates and showing serological cross-reaction with shigella-specific antisera were isolated. phylogenetic analyses revealed that three of the isolates were most closely related to escherichia coli, four to enterobacter sp., two to stenotrophomonas, and two isolates belonged to the gram-posit ...200717171463
shigella ipgb1 promotes bacterial entry through the elmo-dock180 machinery.shigella use a special mechanism to invade epithelial cells called 'the trigger mechanism of entry', which allows epithelial cells to trap several bacteria simultaneously. on contact, shigella deliver effectors into epithelial cells through the type iii secretion system. here, we show that one of the effectors, ipgb1, has a pivotal role in producing membrane ruffles by exploiting the rhog-elmo-dock180 pathway to stimulate rac1 activity. using pulldown assays, we identified engulfment and cell mo ...200717173036
vaccine potential for inactivated shigellae.we used human monocyte-derived dendritic cells (dc) and balb/c mice as models to establish the immunogenic and protective potential of formalin-inactivated shigella spp. incubation of dc with inactivated or live bacteria induced dc maturation and cytokine release. mice immunized orally or intranasally with killed s. flexneri, s. sonnei, or s. dysenteriae developed igg and fecal iga titers to the homologous lps. following respiratory challenge with the live homologous organisms, 80-100% survival ...200717178431
shigella rewrites host transcriptional responses. 200717179964
occurrence of campylobacter jejuni in shiraz, southwest iran.to investigate the occurrence of campylobacter jejuni among other bacterial agents of acute diarrhea.200717159366
an injected bacterial effector targets chromatin access for transcription factor nf-kappab to alter transcription of host genes involved in immune responses.phosphorylation of histone h3 at ser10 increases chromatin accessibility to transcription factor nf-kappab on a subset of genes involved in immune responses. here we report that a bacterial pathogen abrogated phosphorylation of histone h3 to 'shape' the transcriptional responses of infected host cells. we identify the shigella flexneri protein effector ospf as a dually specific phosphatase that dephosphorylated mitogen-activated protein kinases in the nucleus, thus preventing histone h3 phosphor ...200717159983
revisiting the molecular evolutionary history of shigella spp.the theory that shigella is derived from multiple independent origins of escherichia coli (pupo et al. 2000) has been challenged by recent findings that the virulence plasmids (vps) and the chromosomes share a similar evolutionary history (escobar-paramo et al. 2003), which suggests that an ancestral vp entered an e. coli strain only once, which gave rise to shigella spp. in an attempt to resolve these conflicting theories, we constructed three phylogenetic trees in this study: a robust chromoso ...200717160643
case-control study of shigellosis in san francisco: the role of sexual transmission and hiv infection.shigella species infect approximately 450,000 persons annually in the united states. person-to-person transmission of shigella species, which have a low infectious dose, occurs frequently, particularly in areas with poor sanitation and hygiene. sexual transmission of shigella species among men who have sex with men (msm) has been inferred from outbreaks of shigellosis among that population, and limited studies have suggested the importance of human immunodeficiency virus (hiv) infection as a ris ...200717205436
another perfect storm: shigella, men who have sex with men, and hiv. 200717205437
use of linear, weibull, and log-logistic functions to model pressure inactivation of seven foodborne pathogens in milk.survival curves of six foodborne pathogens suspended in ultra high-temperature (uht) whole milk and exposed to high hydrostatic pressure at 21.5 degrees c were obtained. vibrio parahaemolyticus was treated at 300 mpa and other pathogens, listeria monocytogenes, escherichia coli o157:h7, salmonella enterica serovar enteritidis, salmonella enterica serovar typhimurium, and staphylococcus aureus were treated at 600 mpa. all the survival curves showed a rapid initial drop in bacterial counts followe ...200717188197
polar positional information in escherichia coli spherical cells.shigella surface protein icsa and its cytoplasmic derivatives are localized to the old pole of rod-shaped cells when expressed in escherichia coli. in spherical mreb cells, icsa is targeted to ectopic sites and close to one extremity of actin-like mamk filament. to gain insight into the properties of the sites containing polar material, we studied the icsa localization in spherical cells. gfp was exported into the periplasm via the tat pathway and used as a periplasmic space marker. gfp displaye ...200717188233
shigella's ways of manipulating the host intestinal innate and adaptive immune system: a tool box for survival?shigella, a gram-negative invasive enteropathogenic bacterium, causes the rupture, invasion and inflammatory destruction of the human colonic epithelium. this complex and aggressive process accounts for the symptoms of bacillary dysentery. the so-called invasive phenotype of shigella is linked to expression of a type iii secretory system (ttss) injecting effector proteins into the epithelial cell membrane and cytoplasm, thereby inducing local but massive changes in the cell cytoskeleton that lea ...200717213832
shigella chromosomal ipah proteins are secreted via the type iii secretion system and act as effectors.shigella possess 220 kb plasmid, and the major virulence determinants, called effectors, and the type iii secretion system (ttss) are exclusively encoded by the plasmid. the genome sequences of s. flexneri strains indicate that several ipah family genes are located on both the plasmid and the chromosome, but whether their chromosomal ipah cognates can be secreted from shigella remains unknown. here we report that s. flexneri strain, ysh6000 encodes seven ipah cognate genes on the chromosome and ...200717214743
an h-ns-like stealth protein aids horizontal dna transmission in bacteria.the sfh protein is encoded by self-transmissible plasmids involved in human typhoid and is closely related to the global regulator h-ns. we have found that sfh provides a stealth function that allows the plasmids to be transmitted to new bacterial hosts with minimal effects on their fitness. introducing the plasmid without the sfh gene imposes a mild h-ns(-) phenotype and a severe loss of fitness due to titration of the cellular pool of h-ns by the a+t-rich plasmid. this stealth strategy seems t ...200717218529
erosion of interaction networks in reduced and degraded genomes.unlike eukaryotes, which often recruit duplicated genes into existing protein-protein interaction (ppi) networks, the low levels of gene duplication coupled with the high probability of lateral transfer of novel genes alters the manner in which ppi networks can evolve in bacteria. by inferring the ppis present in the ancestor to contemporary gammaproteobacteria, we were able to trace the changes in gene repertoires, and their consequences on ppi network evolution, in several bacterial lineages t ...200717219366
analysis of strategies to successfully vaccinate infants in developing countries against enterotoxigenic e. coli (etec) disease.enterotoxigenic escherichia coli (etec) is the most common bacterial cause of diarrhoea in the world, annually affecting up to 400,000,000 children under 5 years of age living in developing countries (dcs). although etec possesses numerous antigens, the relatively conserved colonization factor (cf) antigens and the heat labile enterotoxin (lt) have been associated with protection and most vaccine candidates have exploited these antigens. a safe and effective vaccine against etec is a feasible go ...200717224212
antibacterial activity and in vitro anti-tumor activity of the extract of the larvae of the housefly (musca domestica).one of the significant characteristics of traditional chinese medicine is the use of insects, other terrestrial arthropods and their products as drugs. in the present work, the extract of housefly (musca domestica) larvae was studied by an agar well diffusion assay and minimum bactericidal concentration (mbc) determination for detection of antimicrobial activity and by mtt assay method to test its in vitro anti-tumor activity. in our studies, the extract inhibited six tested bacterial pathogens ...200717227700
immunogenicity and characterization of wrsf2g11: a second generation live attenuated shigella flexneri 2a vaccine strain.recent clinical trials involving live attenuated shigella vaccine strains sc602 and wrss1 have revealed that deletion of the virg(icsa) gene dramatically reduces virulence in human volunteers. these strains can be given at low oral doses and induce a strong, and in some cases, protective immune responses. however, residual vaccine associated reactogenicity suggests that further attenuation is required. a recent clinical trial indicated that the set and sen enterotoxin genes contribute to the sym ...200717229494
role of infection in irritable bowel syndrome.infection by pathogenic organisms leads to mucosal damage and disruption of the gut's extensive commensal flora, factors which may lead to prolonged bowel dysfunction. six to 17% of unselected irritable bowel syndrome (ibs) patients believe their symptoms began with an infection, which is supported by prospective studies showing a 4%-31% incidence of postinfectious ibs-(pi) following bacterial gastroenteritis. the wide range of incidence can be accounted for by differences in risk factors, which ...200717238025
using european travellers as an early alert to detect emerging pathogens in countries with limited laboratory resources.the volume, extent and speed of travel have dramatically increased in the past decades, providing the potential for an infectious disease to spread through the transportation network. by collecting information on the suspected place of infection, existing surveillance systems in industrialized countries may provide timely information for areas of the world without adequate surveillance currently in place. we present the results of a case study using reported cases of shigella dysenteriae serotyp ...200717239228
high genetic stability of integrons in clinical isolates of shigella spp. of worldwide origin.over a 12-year period, 68 shigella strains (31 s. sonnei, 30 s. flexneri, 4 s. dysenteriae, and 3 s. boydii strains) were collected in a french university hospital from the stools of patients who generally had a recent history of travel to various parts of the world (91%), particularly africa (67%). these strains were often resistant (streptomycin, spectinomycin, trimethoprim, tetracycline, and sulfonamides, 66 to 84%; ampicillin and chloramphenicol, 34 to 38%; nalidixic acid, 4%) and even multi ...200717242143
the catalase reaction of shigella species and its use in rapid screening for epidemic shigella dysenteriae type 1.as epidemic dysentery caused by shigella dysenteriae type 1 is associated with high mortality, early identification of outbreaks is important. since s. dysenteriae type 1 differs from most of the enterobacteriaceae in that it does not produce catalase, a test for catalase may provide a useful screening method. the ability of a catalase test to provide rapid identification of s. dysenteriae type 1 has now been assessed, using isolates of this pathogen from five continents, shigella of other speci ...200717244412
detection of genogroup i and ii human picobirnaviruses showing small genomic rna profile causing acute watery diarrhoea among children in kolkata, india.picobirnaviruses (pbvs) with bisegmented small rna genome profile (1.75 and 1.55kbp for segment 1 and 2, respectively) were detected from 1999 to 2003 in faecal specimens of acute watery diarrhoea cases, largely children (n=20) and an adult in kolkata, india. varying degrees of dehydration necessitated their visit to hospital for further treatment and management of acute watery diarrhoea. pbv was associated with rotavirus (n=3) or astrovirus (n=3) and with both in one case. no co-infection with ...200717049316
self-chaperoning of the type iii secretion system needle tip proteins ipad and bipd.bacteria expressing type iii secretion systems (t3ss) have been responsible for the deaths of millions worldwide, acting as key virulence elements in diseases ranging from plague to typhoid fever. the t3ss is composed of a basal body, which traverses both bacterial membranes, and an external needle through which effector proteins are secreted. we report multiple crystal structures of two proteins that sit at the tip of the needle and are essential for virulence: ipad from shigella flexneri and b ...200717077085
octaplex pcr and fluorescence-based capillary electrophoresis for identification of human diarrheagenic escherichia coli and shigella spp.a multiplex pcr assay, amplifying seven specific virulence genes and one internal control gene in a single reaction, was developed to identify the five main pathotypes of diarrheagenic escherichia coli and shigella spp. the virulence genes selected for each category were stx1, stx2, and eaea for enterohemorrhagic e. coli (ehec), eaea for enteropathogenic e. coli (epec), stib and lti for enterotoxigenic e. coli (etec), ipah for enteroinvasive e. coli (eiec) and shigella spp., and aggr for enteroa ...200717079041
changing epidemiology of shigellosis and emergence of ciprofloxacin-resistant shigellae in india. 200717122011
a microbial diagnostic microarray technique for the sensitive detection and identification of pathogenic bacteria in a background of nonpathogens.a major challenge in microbial diagnostics is the parallel detection and identification of low-bundance pathogens within a complex microbial community. in addition, a high specificity providing robust, reliable identification at least at the species level is required. a microbial diagnostic microarray approach, using single nucleotide extension labeling with gyrb as the marker gene, was developed. we present a novel concept applying competitive oligonucleotide probes to improve the specificity o ...200717123456
ipad is localized at the tip of the shigella flexneri type iii secretion apparatus.type iii secretion (t3s) systems are used by numerous gram-negative pathogenic bacteria to inject virulence proteins into animal and plant host cells. the core of the t3s apparatus, known as the needle complex, is composed of a basal body transversing both bacterial membranes and a needle protruding above the bacterial surface. in shigella flexneri, ipad is required to inhibit the activity of the t3s apparatus prior to contact of bacteria with host and has been proposed to assist translocation o ...200717110044
enteropathogenic escherichia coli, shigella flexneri, and listeria monocytogenes recruit a junctional protein, zonula occludens-1, to actin tails and pedestals.enteropathogenic escherichia coli, shigella flexneri, and listeria monocytogenes induce localized actin polymerization at the cytoplasmic face of the plasma membrane or within the host cytoplasm, creating unique actin-rich structures termed pedestals or actin tails. the process is known to be mediated by the actin-related protein 2 and 3 (arp2/3) complex, which in these cases acts downstream of neural wiskott-aldrich syndrome protein (n-wasp) or of a listerial functional homolog of wasp family p ...200717118974
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