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reaching a consensus on management practices and vaccine development targets for mitigation of infectious diarrhoea among deployed us military forces.this study is part of a research effort to identify and quantify factors related to the cost-effectiveness of a vaccine acquisition strategy to reduce the burden of infectious diarrhoea on us military personnel deployed overseas. where evidence is lacking in the scientific literature, or considerable uncertainty exists, it is often necessary to develop best estimates with ranges of certainty. to this end, a modified 'delphi' survey technique to obtain the best estimates for uncertain parameters ...200818284518
the shf gene of a shigella flexneri homologue on the virulent plasmid paa2 of enteroaggregative escherichia coli 042 is required for firm biofilm formation.enteroaggregative escherichia coli (eaec) is an increasingly important cause of diarrhea in both developing and industrialized countries, and is characterized by strong biofilm formation on the intestinal mucosa. sequencing of the virulent plasmid paa2 of the prototype eaec 042 revealed a cluster of three open reading frames (orfs; shf, capu, and virk) ca. 93% identical to a similar cluster located in shigella flexneri. the function of the first orf shf protein is not known, but the closest well ...200818293034
single residue determines the specificity of neutrophil elastase for shigella virulence factors.human neutrophil elastase (ne) is a key host defense protease that cleaves virulence factors of gram-negative bacteria. ne and cathepsin g (cg) are chymotrypsin-like serine proteases with sequence and structural similarities, and both are abundant in neutrophil granules. unlike ne, cg does not cleave virulence factors of enteric bacteria. through structure-function analysis, we identified regions in ne that are essential for cleaving shigella virulence proteins. ne residues at eight different po ...200818295791
cmy-2-type plasmid-mediated ampc beta-lactamase finally emerging in argentina. 200818242960
antimicrobial activity of 2,5-dihydroxy-3-methyl-1,4-benzoquinone from embelia schimperi.chromatographic separation of an ethyl acetate extract from embelia schimperi led to the isolation of a new compound identified as 2,5-dihydroxy-3-methyl-1,4-benzoquinone (1) on the basis of spectroscopic and physical data. the plant's crude extract and pure compound 1 were assayed for in vitro antimicrobial activity against clinical strains of salmonella spp., proteus spp., pseudomonas aeruginosa, klebsiella pneumoniae, escherichia coli, cryptococcus neoformans, shigella dysentriae and staphylo ...200818386487
a cost function analysis of shigellosis in thailand.the purpose of this study was to develop a cost function model to estimate the public treatment cost of shigellosis patients in thailand.200818387071
eukaryotic expression and antimicrobial spectrum determination of the peptide tachyplesin ii.ta0-a, the gene encoding the mature antimicrobial peptide tachyplesin ii, was engineered to optimize the coding sequence according to codon usage bias in yeast. ta0-a was efficiently expressed in the methylotrophic yeast pichia pastoris strain smd1168. the recombinant peptide ta0 reached 150mg/l after methanol induction for 6 d. ta0 was rapidly purified to homogeneity by a single step of size-exclusion chromatography. the minimal lethal concentrations of ta0 to the escherichia coli strain k12 wa ...200818249136
[shigella spp infections in children living in the metropolitan region, chile, during summer of 2004-2005].shigella spp is a frequent cause of diarrhea in children. antimicrobials decrease the duration of diarrhea and pathogen excretion. however, the increasing resistance limits their therapeutic value.200818259649
preliminary foodnet data on the incidence of infection with pathogens transmitted commonly through food--10 states, 2007.the foodborne diseases active surveillance network (foodnet) of cdc's emerging infections program collects data from 10 u.s. states regarding diseases caused by pathogens commonly transmitted through food. foodnet quantifies and monitors the incidence of these infections by conducting active, population-based surveillance for laboratory-confirmed infections. this report describes preliminary surveillance data for 2007 and compares them with data for previous years. in 2007, the estimated inciden ...200818401330
characterisation of escherichia coli strains involved in transcytosis across gut epithelial cells exposed to metabolic and inflammatory stress.translocation of normally non-pathogenic bacteria across the gut may drive inflammatory responses associated with sepsis and inflammatory bowel disease. recent evidence suggests translocation may not be purely passive, but occurs via novel transcellular pathways activated in enterocytes by inflammatory and metabolic stress. the specificity of this pathway with respect to different e. coli strains and other bacterial species, and possible molecular determinants of the "translocating" phenotype ha ...200818403240
[shigellosis outbreak with 146 cases related to a fair].on september 3, 2005, the ciudad real public health service (spain) received a report of 20 cases of gastroenteritis in the municipality of daimiel. we conducted an investigation to determine the cause or causes of the outbreak and to implement control measures. most of the cases involved young people who visited the municipality's fair.200818261440
analysis of bacterial dna in synovial tissue of tunisian patients with reactive and undifferentiated arthritis by broad-range pcr, cloning and sequencing.bacteria and/or their antigens have been implicated in the pathogenesis of reactive arthritis (rea). several studies have reported the presence of bacterial antigens and nucleic acids of bacteria other than those specified by diagnostic criteria for rea in joint specimens from patients with rea and various arthritides. the present study was conducted to detect any bacterial dna and identify bacterial species that are present in the synovial tissue of tunisian patients with reactive arthritis and ...200818412942
geographic analysis of shigellosis in vietnam.geographic and ecological analysis may provide investigators useful ecological information for the control of shigellosis. this paper provides distribution of individual shigella species in space, and ecological covariates for shigellosis in nha trang, vietnam. data on shigellosis in neighborhoods were used to identify ecological covariates. a bayesian hierarchical model was used to obtain joint posterior distribution of model parameters and to construct smoothed risk maps for shigellosis. neigh ...200818296100
extracellular-loop peptide antibodies reveal a predominant hemichannel organization of connexins in polarized intestinal cells.shigella, the causative agent of bacillary dysentery, invades colonic epithelial cells to elicit an intense inflammatory reaction leading to destruction of the mucosa. atp-dependent paracrine signalling induced by connexin (cx) hemichannel opening was previously shown to favor shigella flexneri invasion and dissemination in transfectants of hela cells [g. tran van nhieu, c. clair, r. bruzzone, m. mesnil, p. sansonetti and l. combettes. (2003). connexin-dependent intercellular communication incre ...200818267319
socioeconomic risk factors for bacterial gastrointestinal infections.bacterial gastrointestinal infections cause considerable morbidity in industrialized countries, but little is known about socioeconomic factors affecting the risk of infection.200818300694
structures of the shigella flexneri type 3 secretion system protein mxic reveal conformational variability amongst homologues.many gram-negative pathogenic bacteria use a complex macromolecular machine, known as the type 3 secretion system (t3ss), to transfer virulence proteins into host cells. the t3ss is composed of a cytoplasmic bulb, a basal body spanning the inner and outer bacterial membranes, and an extracellular needle. secretion is regulated by both cytoplasmic and inner membrane proteins that must respond to specific signals in order to ensure that virulence proteins are not secreted before contact with a euk ...200818304577
role of rna polymerase sigma-factor (rpos) in induction of glutamate-dependent acid-resistance of escherichia albertii under anaerobic conditions.escherichia albertii is a potential enteric food-borne pathogen with poorly defined genetic and biochemical properties. acid resistance is perceived to be an important property of enteric pathogens, enabling them to survive passage through stomach acidity so that they may colonize the mammalian gastrointestinal tract. we analyzed glutamate-dependent acid-resistance pathway (gdar) in five e. albertii strains that have been identified so far. we observed that the strains were unable to induce gdar ...200818422618
comparing the antimicrobial effectiveness of nacl and kcl with a view to salt/sodium replacement.a study using a small range of pathogenic bacterial species (aeromonas hydrophila, enterobacter sakazakii, shigella flexneri, yersinia enterocolitica and 3 strains of staphylococcus aureus) has shown that potassium chloride has an equivalent antimicrobial effect on these organisms when calculated on a molar basis. combined nacl and kcl experiments were carried out and data was analysed using a modification to the lambert and lambert [lambert, r.j.w., and lambert, r., 2003. a model for the effica ...200818423764
the o-polysaccharide of escherichia coli o112ac has the same structure as that of shigella dysenteriae type 2 but is devoid of o-acetylation: a revision of the s. dysenteriae type 2 o-polysaccharide structure.the o-antigen structure of shigella dysenteriae type 2 was reinvestigated using chemical modifications along with high-resolution 2d (1)h and (13)c nmr spectroscopy. the o-antigen was found to contain a pyruvic acid acetal, which was overlooked in an early study, and the following revised structure of the pentasaccharide repeating unit was established: where approximately 70% glcnac residues bear an o-acetyl group at position 3. the o-antigen of escherichia coli o112ac was found to have the same ...200818308298
retrograde traffic in the biosynthetic-secretory route.in the biosynthetic-secretory route from the rough endoplasmic reticulum, across the pre-golgi intermediate compartments, the golgi apparatus stacks, trans golgi network, and post-golgi organelles, anterograde transport is accompanied and counterbalanced by retrograde traffic of both membranes and contents. in the physiologic dynamics of cells, retrograde flow is necessary for retrieval of molecules that escaped from their compartments of function, for keeping the compartments' balances, and mai ...200818270728
pyrosequencing analysis of the gyrb gene to differentiate bacteria responsible for diarrheal diseases.pathogens causing acute diarrhea include a large variety of species from enterobacteriaceae and vibrionaceae. a method based on pyrosequencing was used here to differentiate bacteria commonly associated with diarrhea in china; the method is targeted to a partial amplicon of the gyrb gene, which encodes the b subunit of dna gyrase. twenty-eight specific polymorphic positions were identified from sequence alignment of a large sequence dataset and targeted using 17 sequencing primers. of 95 isolate ...200818324428
insecticidal properties and microbial contaminants in a spodoptera exigua multiple nucleopolyhedrovirus (baculoviridae) formulation stored at different temperatures.the spodoptera exigua (hübner) multiple nucleopolyhedrovirus (semnpv) is currently being tested as a biological insecticide for use in greenhouse crops in southern spain. we performed a study in which semipurified semnpv occlusion bodies (obs) were formulated in phosphate-buffered saline, ph 6.5, with 5% (vol:vol) glycerol and 0.15% (wt:vol) sorbic acid, and they were stored at -20, 4, or 25 degrees c during 18 mo. initial aerobic counts (+/-se) averaged 1.4 (+/-0.17) x 10(7) colony-forming unit ...200818330114
shigellosis: the current status of vaccine development.shigellosis, a major form of bacillary dysentery, is caused by infection with shigella organisms. in poor countries, shigella-caused dysentery is endemic and causes an estimated 163 million illness episodes annually and more than one million deaths. although several strategies have been used to develop vaccines targeting shigellosis, none has been licensed for use outside china. owing to the wide range of shigella serotypes and subtypes, there is a need for a multivalent vaccine representing pre ...200818448978
subversion of actin dynamics by espm effectors of attaching and effacing bacterial pathogens.rho gtpases are common targets of bacterial toxins and type iii secretion system effectors. ipgb1 and ipgb2 of shigella and map of enteropathogenic (epec) and enterohemorrhagic (ehec) escherichia coli were recently grouped together on the basis that they share a conserved wxxxe motif. in this study, we characterized six wxxxe effectors from attaching and effacing pathogens: trca and espm1 of epec strain b171, espm1 and espm2 of ehec strain sakai and espm2 and espm3 of citrobacter rodentium. we s ...200818331467
evaluation of faecal occult blood test and lactoferrin latex agglutination test in screening hospitalized patients for diagnosing inflammatory and non-inflammatory diarrhoea in dhaka, bangladesh.inflammatory diarrhoea (id) resulting from shigella, salmonella, campylobacter and entamoeba histolytica requires specific diagnosis for therapy. differentiation between id and non-inflammatory diarrhoea (nid) is often not clinically possible. a faecal occult blood test (fobt) correlates with faecal leucocytes. lactoferrin indicates an inflammatory process as a marker for faecal leucocytes. we evaluated diagnostic values of lactoferrin latex agglutination test (lt) either alone or in combination ...200818196900
new information about pediatric foodborne infections: the view from foodnet.diarrheal illness is a significant burden to children and their parents. recent studies describing the etiologic agents that cause diarrheal illness and examining the risk factors for the most common bacterial enteric pathogens are presented.200818197044
molecular pathogenesis of shigella spp.: controlling host cell signaling, invasion, and death by type iii secretion.shigella spp. are gram-negative pathogenic bacteria that evolved from harmless enterobacterial relatives and may cause devastating diarrhea upon ingestion. research performed over the last 25 years revealed that a type iii secretion system (t3ss) encoded on a large plasmid is a key virulence factor of shigella flexneri. the t3ss determines the interactions of s. flexneri with intestinal cells by consecutively translocating two sets of effector proteins into the target cells. thus, s. flexneri co ...200818202440
regulation of expression and secretion of nleh, a new non-locus of enterocyte effacement-encoded effector in citrobacter rodentium.together with enterohemorrhagic escherichia coli and enteropathogenic escherichia coli, citrobacter rodentium is a member of the attaching-and-effacing (a/e) family of bacterial pathogens. a/e pathogens use a type iii secretion system (t3ss) to translocate an assortment of effector proteins, encoded both within and outside the locus of enterocyte effacement (lee), into the colonized host cell, leading to the formation of a/e lesions and disease. here we report the identification and characteriza ...200818223087
ipgb1 and ipgb2, two homologous effectors secreted via the mxi-spa type iii secretion apparatus, cooperate to mediate polarized cell invasion and inflammatory potential of shigella flexenri.type iii secretion systems (t3ss) are present in many pathogenic gram-negative bacteria and mediate the translocation of bacterial effector proteins into host cells. here, we report the phenotypic characterization of s. flexneri ipgb1 and ipgb2 mutants, in which the genes encoding the ipgb1 and ipgb2 effectors have been inactivated, either independently or simultaneously. like ipgb1, we found that ipgb2 is secreted by the t3ss and its secretion requires the spa15 chaperone. upon infection of sem ...200818316224
ph sensitivity of type iii secretion system tip proteins.many pathogenic gram-negative bacteria employ type iii secretion systems to transport proteins into the host cell membrane and cytoplasm to subvert normal cellular functions. the type iii secretion apparatus consists of a basal body spanning the inner and outer bacterial membranes and a needle which extends away from the bacterium. recent work has found that a special class of proteins localizes to the tip of the needle to control secretion of effector proteins. five of these tip proteins are ip ...200818175320
[antigenic polysaccharides of bacteria: 41. structures of the o-specific polysaccharides of shigella dysenteriae types 4 and 5 revised by nmr spectroscopy].the earlier established structures of the acidic o-specific polysaccharides from two typical strains of the shigella dysenteriae bacterium were revised using modern nmr spectroscopy techniques. in particular, the configurations of the glycosidic linkages of glcnac (s. dysenteriae type 4) and mannose (s. dysenteriae type 5) residues were corrected. in addition, the location of the sites of nonstoichiometric o-acetylation in s. dysenteriae type 4 was determined: the lateral fucose residue was show ...200818695724
[treatment of recurrent clostridium difficile-associated diarrhoea with a suspension of donor faeces].to study the effect of treating recurrent clostridium difficile-associated diarrhoea (cdad) with a suspension of donor faeces.200818808083
epidemiological evidence of multidrug-resistant shigella sonnei colonization in india by sentinel surveillance in a japanese quarantine station.we applied a previously reported method to clarify whether a multidrug-resistant shigella colonizes in a south asian country. at kansai airport quarantine station, stool samples were collected from overseas travelers who reported a history of diarrhea. shigella strains were isolated, ranging from 53 to 106 (average, 82.4) isolates/year (2001-2005), and almost 80% of the isolates were shigella sonnei. the most frequent country of origin was india. strains from the country of the most frequent ori ...200818697484
structural and functional characterization of human iba proteins.iba2 is a homolog of ionized calcium-binding adapter molecule 1 (iba1), a 17-kda protein that binds and cross-links filamentous actin (f-actin) and localizes to membrane ruffles and phagocytic cups. here, we present the crystal structure of human iba2 and its homodimerization properties, f-actin cross-linking activity, cellular localization and recruitment upon bacterial invasion in comparison with iba1. the iba2 structure comprises two central ef-hand motifs lacking bound ca2+. iba2 crystallize ...200818699778
epidemiology of highly endemic multiply antibiotic-resistant shigellosis in children in the peruvian amazon.our goal was to estimate the impact of a shigella vaccine in an area where shigellosis is endemic by characterizing the disease burden and antibiotic-resistance profiles of isolates and by determining the prevalence of shigella flexneri serotypes.200818710884
inhibitory effects of sage extract on the growth of enteric bacteria.antibacterial activity of sage extract at concentrations of 0.1, 0.05, 0.025, 0.0125, 0.00625, 0.003125, 0.00156, 0.0005 and 0.00025 g dl(-1) against salmonella typhi, shigella sonnei, s. flexneri, proteus vulgaris, staphylococcus aureus, etec escherichia coli and pseudomonas aeruginosa was evaluated. susceptibility testing of bacterial strains against 18 antibiotics was also performed for comparison. the results showed that p. aeruginosa and etec e. coli were completely resistant to sage extrac ...200818817180
[rotaviruses in younger children in novosibirsk in 2005-2007: detection and genotyping].examination of 1898 patients with acute enteric infection from march 2005 to february 2007 showed that group a rotaviruses were the most frequent cause (35%) of acute gastroenteritis among children under 3 years of age. majority of cases of rotavirus infection was detected in infants under 1 year of age (71.8%). the peak of sporadic incidence was observed between february and may. high rate of mixed infection (45.6%) was observed - associations of rotaviruses with other viruses (noroviruses, ast ...200818819400
use of mchi encoding immunity to the antimicrobial peptide microcin h47 as a plasmid selection marker in attenuated bacterial live vectors.live attenuated bacterial strains expressing heterologous antigens represent an attractive vaccine development strategy. however, the use of drug resistance genes for the selection of expression plasmids introduced into live vectors poses theoretical health risks. therefore, we developed a novel approach for plasmid selection based on immunity to the antimicrobial peptide microcin h47 (mcch47). two expression plasmids encoding the reporter green fluorescent protein (gfpuv) were constructed; sele ...200818663003
novel cassette arrays of integrons in clinical strains of enterobacteriaceae in china.one hundred and forty-two enterobacteriaceae isolates randomly selected from four general hospitals in nanjing region of china were investigated for antibiotic susceptibility, the presence of integrons and the characterisation of gene cassettes. eighty-five (59.9%) enterobacteriaceae strains contained class 1 integrons, and 17 (65.4%) of 26 shigella contained class 2 integrons. class 3 integrons were not detected in this study. restriction fragment length polymorphism (rflp) and dna sequencing a ...200818778917
use of flow cytometry in an apoptosis assay to determine ph and temperature stability of shiga-like toxin 1.shiga toxins and shiga-like toxins (stx) are a relatively large group of cytotoxins produced by certain serotypes of shigella and e. coli (stec). these toxins are responsible for diarrhea, hemorrhagic colitis and may induce hemolytic uremic syndrome (hus) with serious consequences in young children. the toxins are proteins made up of 5 small b subunits responsible for binding to an outer membrane ligand on host cells and surround the larger, biologically active a subunit. for shiga-like toxin 1 ...200818710788
[molecular typing of isolates from two dysentery outbreaks in chengdu, through pulsed field gel electrophoresis technology].using pulsed field gel electrophoresis (pfge) and polymerase chain reaction (pcr) typing to analyze strains isolated from two outbreaks caused by shigella sonnei and to trace the source of infection.200818788530
the roles of two-component systems in virulence of pathogenic escherichia coli and shigella spp.two-component systems (tcss) are well conserved among e. coli strains, including pathogenic e. coli and also closely related shigella spp. although 25% of the genome of pathogenic e. coli is strain-specific, only small number of strain-specific tcss is found. regulation of virulence genes in response to environmental stimuli is partly dependent on tcss commonly present in nonpathogenic e. coli strains. some virulence genes are directly regulated by response regulator oftcs but some are affected ...200818792690
all blood, no stool: enterohemorrhagic escherichia coli o157:h7 infection.enterohemorrhagic escherichia coli serotype o157:h7 is a pathotype of diarrheagenic e. coli that produces one or more shiga toxins, forms a characteristic histopathology described as attaching and effacing lesions, and possesses the large virulence plasmid po157. the bacterium is recognized worldwide, especially in developed countries, as an emerging food-borne bacterial pathogen, which causes disease in humans and in some animals. healthy cattle are the principal and natural reservoir of e. col ...200818716441
acute diarrhea due to enteropathogenic bacteria in patients at hospitals in tehran.during a study examining causes of diarrhea from may 2004 to may 2005, 808 stool specimens were collected from patients with acute diarrhea in tehran. fecal samples were cultured and identified according to the standard biochemical methods. molecular identification of enteropathogens was carried out by amplification of their virulence genes by polymerase chain reaction. a total of 369 (45.6%) bacterial pathogens were recovered from 808 patients as follows: shigella spp., 155 (45.6%); diarrheagen ...200818653967
characterization of soluble complexes of the shigella flexneri type iii secretion system atpase.the conserved atpase of type iii secretion systems is critical to the export of substrates through the apparatus. we present a characterization of the native t3ss atpase, spa47, from the cytoplasm of shigella flexneri, demonstrating it to be in two distinct high-molecular-weight complexes with spa33: mxin and mxik.200818657109
microcalorimetric studies of the action on four organic acids in radix isatidis on the growth of microorganisms.the actions of four organic acids in radix isatidis, a traditional chinese medicinal (tcm) herb, on escherichia coli, staphylococcus aureus and shigella dysenteriae growth were investigated by microcalorimetry. the four organic acids were syringic acid, 2-amino-benzoic acid, salicylic acid and benzoic acid. the power-time curves of escherichia coli, staphylococcus aureus and shigella dysenteriae growth with and without organic acids were acquired, meanwhile the extent and duration of inhibitory ...200818616177
structures of synthetic o-antigen fragments from serotype 2a shigella flexneri in complex with a protective monoclonal antibody.the anti-lps igg mab f22-4, raised against shigella flexneri serotype 2a bacteria, protects against homologous, but not heterologous, challenge in an experimental animal model. we report the crystal structures of complexes formed between fab f22-4 and two synthetic oligosaccharides, a decasaccharide and a pentadecasaccharide that were previously shown to be both immunogenic and antigenic mimics of the s. flexneri serotype 2a o-antigen. f22-4 binds to an epitope contained within two consecutive 2 ...200818621718
invitro antibacterial activity of crude preparation of myrtle (myrtus communis) on common human pathogens.myrtle "addus" (myrtus communis) has long history as a traditional medicine/or different infectious disease by many peoples of the world and in ethiopia too.200818711991
functional characterization of the shigella dysenteriae heme abc transporter.the heme atp binding cassette (abc) transporter, shuuv, of shigella dysenteriae has been incorporated into proteoliposomes. functional characterization of shuuv revealed that atp hydrolysis and transport of heme from the periplasmic binding protein, shut, to the cytoplasmic binding protein, shus, are coupled. site-directed mutagenesis of shut residues proposed to be required for stabilization of the complex abolished heme transport. furthermore, residues his-252 and his-262, located in the trans ...200818616281
first italian case of cyclosporiasis in an immunocompetent woman: local acquired infection.cyclospora cayetanensis is a coccidian agent of chronic diarrhea in humans with a worldwide distribution. we report the first documented case of acquired cyclosporiasis in italy. the patient was an immunocompetent woman with no recent history of travel outside the country. microscopy detected cyclospora oocysts in a feces sample. pcr detected the pathogen in a second sample, which had tested negative by microscopy. the patient was investigated to detect other microorganisms in feces, such as sal ...200818623995
a potential plasmid-curing agent, 8-epidiosbulbin e acetate, from dioscorea bulbifera l. against multidrug-resistant bacteria.bioassay-guided fractionation of an aqueous methanolic extract of dioscorea bulbifera l. bulbs was performed using organic solvents. a novel plasmid-curing compound was identified as 8-epidiosbulbin e acetate (eea) (norditerpene) on the basis of modern spectroscopic analysis and x-ray crystallography. eea exhibited broad-spectrum plasmid-curing activity against multidrug-resistant (mdr) bacteria, including vancomycin-resistant enterococci. eea cured antibiotic resistance plasmids (r-plasmids) fr ...200818718743
[detection of enteric pathogenic bacteria from surface waters by quantitative polymerase chain reaction (qpcr)].a rapid quantitative polymerase chain reaction (qpcr) analysis method with universal primers was developed to detect cell densities of the enteric pathogenic bacteria from 5 surface water of xi'an city for 4 months continuously. and the detection results by qpcr method were compared with counts of coliforms colony-forming units (cfu) determined by membrane filter (mf) analysis. the results showed that qpcr method had an estimated 94% confidence, and detection limit was 2.7 escherichia coli cells ...200818624175
is irritable bowel syndrome an inflammatory disorder?histopathologic data demonstrate low-grade mucosal inflammation in a subset of patients with irritable bowel syndrome (ibs). this inflammatory infiltrate is mainly represented by increased numbers of t lymphocytes and mast cells lying in the lamina propria. the close apposition of immunocytes to gut nerves supplying the mucosa provides a basis for neuroimmune cross-talk, which may explain gut sensorimotor dysfunction and related symptoms in patients with ibs. a previous gastroenteritis (due to c ...200818627650
role of nleh, a type iii secreted effector from attaching and effacing pathogens, in colonization of the bovine, ovine, and murine gut.the human pathogen enterohemorrhagic escherichia coli (ehec) o157:h7 colonizes human and animal gut via formation of attaching and effacing lesions. ehec strains use a type iii secretion system to translocate a battery of effector proteins into the mammalian host cell, which subvert diverse signal transduction pathways implicated in actin dynamics, phagocytosis, and innate immunity. the genomes of sequenced ehec o157:h7 strains contain two copies of the effector protein gene nleh, which share 49 ...200818725419
a single-tube screen for salmonella and shigella.salmonella and shigella species are routinely sought in stool specimens submitted for culture. it is a common practice to screen lactose-negative colonies by using triple sugar iron agar, lysine iron agar, and christensen urea agar to determine if further identification is necessary. we designed and evaluated a novel combination of media, which are layered in a single tube, for screening isolates suspected to possibly represent salmonella or shigella. we tested this media combination with 106 sa ...200818628099
haemolytic uraemic syndrome in children admitted to a rural district hospital in kenya.we studied children admitted to kilifi district hospital, kenya, between 1997 and 2005 with haemolytic uraemic syndrome (hus) and reviewed their records in order to determine the clinical features and outcomes of the disease. thirty-one children fulfilled the criteria: 21 (68%) had diarrhoea-associated hus (d + hus), the remainder did not (d-hus); five had involvement of the central nervous system. those with d-hus had lower haemoglobin and platelet counts when compared with those with d + hus. ...200818628547
crystal structure of a glutamate/aspartate binding protein complexed with a glutamate molecule: structural basis of ligand specificity at atomic resolution.the crystal structure of a periplasmic l-aspartate/l-glutamate binding protein (debp) from shigella flexneri complexed with an l-glutamate molecule has been determined and refined to an atomic resolution of 1.0 a. there are two debp molecules in the asymmetric unit. the refined model contains 4462 non-hydrogen protein atoms, 730 water molecules, 2 bound glutamate molecules, and 2 tris molecules from the buffer used in crystallization. the final r(cryst) and r(free) factors are 13.61% and 16.89%, ...200818640128
simultaneous detection of six human diarrheal pathogens by using dna microarray combined with tyramide signal amplification.multiplex pcr and dna microarray were combined with tyramide signal amplification (tsa) to develop a reliable method suitable for simultaneous detection of six species of human diarrheal pathogens (yersinia enterocolitica, shigella spp, salmonella typhi, brucella spp, vibrio cholera and escherichia coli o157:h7). meanwhile, our method could distinguish v. cholera serotype o1 from o139, and o157:h7 from o157: non-h7. this assay conferred a specificity of 100% for target pathogens. the limit of de ...200818655810
the c-terminus of ipac is required for effector activities related to shigella invasion of host cells.invasion plasmid antigen c (ipac) is secreted by the shigella flexneri type iii secretion system (ttss) as an essential trigger of epithelial cell invasion. at the molecular level, ipac possesses a distinct functional organization. the ipac c-terminal region between amino acids 319 and 345 is predicted to form a coiled-coil structure. such alpha-helical motifs appear to be a recurring structural theme among ttss components. together with ipab, this ipac region is also required for the formation ...200818656530
overview of the inactivation by 254 nm ultraviolet radiation of bacteria with particular relevance to biodefense.our goal was to ultimately predict the sensitivity of untested bacteria (including those of biodefense interest) to ultraviolet (uv) radiation. in this study, we present an overview and analysis of the relevant 254 nm data previously reported and available in the literature. the amount of variability in this data prevented us from determining an "average" response for any bacterium. therefore, we developed particular selection criteria to include the data in our analysis and suggested future gui ...200818627518
the interplay between entamoeba and enteropathogenic bacteria modulates epithelial cell damage.mixed intestinal infections with entamoeba histolytica, entamoeba dispar and bacteria with exacerbated manifestations of disease are common in regions where amoebiasis is endemic. however, amoeba-bacteria interactions remain largely unexamined.200818648517
shigellosis in puducherry. 200818765885
antimicrobial resistance in shigella species isolated in dakar, senegal (2004-2006).from may 2004 to october 2006, a prospective study was carried out in dakar, senegal, to update information about the antimicrobial susceptibility of shigella spp. isolated from stool specimens. among the 165 non-duplicate strains collected, 81 (49%) were identified as shigella flexneri, 75 (45%) as shigella sonnei, 5 (3%) as shigella boydii, and 4 (2%) as shigella dysenteriae. disk diffusion testing revealed that the majority of isolates were resistant to sulphonamides, trimethoprim-sulfamethox ...200818653976
variable length tandem repeat polyglutamine sequences in the flexible tether region of the tsr chemotaxis receptor of escherichia coli.methyl-accepting chemotaxis proteins (mcps) are receptors that play an important role in bacterial chemotaxis. methylation of tsr, the mcp that mediates chemotaxis towards serine in escherichia coli, is thought to be facilitated by binding of the methyltransferase to a flexible tether region at the c-terminal end of tsr. this study analysed natural length variants of the tether that occur in e. coli due to genetic instability in tandem repeat dna sequences that code for glutaminyl (q) residues, ...200818667570
[the distribution and antimicrobial resistance tendency of pathogens associated with diarrhea in beijing].to monitor the constituents and resistant tendency of bacterial pathogens isolated from diarrheal patients in our hospital form 1994 to 2005 to offer the basis for guiding epidemiologic study, vaccination research and clinical treatment.200818843955
[analysis of pulsed-field gel electrophoresis molecular subtyping of shigella strains in shenzhen].to analyze the genetic relations of shigella isolated from shenzhen in 2001-2006 and develop primary molecular subtyping surveillance network of shigella.200818844079
bacterial biosensors for rapid and effective monitoring of biodegradation of organic pollutants in wastewater effluents.significant amounts of toxic substances which are hazardous to animals, plants, microorganisms, and other living organisms including humans are released annually into aquatic and terrestrial environments, mostly from improper wastewater discharges. early detection of such pollutants in wastewater effluents and proper monitoring before their final release into the environment is therefore necessary. in this study, two whole-cell bacterial biosensors were constructed by transforming competent cell ...200818688458
prevention of the cytopathic effect induced by clostridium difficile toxin b by active rac1.clostridium difficile toxin b (tcdb) glucosylates low molecular weight gtp-binding proteins of the rho subfamily and thereby causes actin re-organization (cell rounding). this "cytopathic effect" has been generally attributed to rhoa inactivation. here we show that cells expressing non-glucosylatable rac1-q61l are protected from the cytopathic effect of tcdb. in contrast, cells expressing rhoa-q63l or mock-transfected cells are fully susceptible for the cytopathic effect of tcdb. these findings ...200818848548
liquid chromatography/mass spectrometry characterization of escherichia coli and shigella species.liquid chromatography/quadrupole time of flight mass spectrometry (lc/qtof ms) utilizing electrospray ionization was employed to monitor protein expression in escherichia coli and shigella organisms. comparison with maldi/tof-ms revealed more proteins, particularly above 15 kda. a combination of automated charge state deconvolution, spectral mirroring, and spectral subtraction was used to reveal subtle differences in the lc/ms data. reproducible intact protein biomarker candidates were discovere ...200818692404
[new selective indicator medium for detection of aeromonas and plesiomonas: unisc agar].we evaluated a new selective indicator medium (unisc agar) for isolation of classical enteropathogens, aeromonas spp and plesiomonas shigelloides. the xylose fermentation capacity is indicated by a yellow color (fermenting agents) or blue (no fermenting agent). this, together with the oxidase test, establishes it as an indicator for detecting aeromonas and plesiomonas shigelloides. its productivity and selectivity, as assessed using the absolute count index and relative count index, indicate it ...200818853024
bacterial conjugation in the cytoplasm of mouse cells.intracellular pathogenic organisms such as salmonellae and shigellae are able to evade the effects of many antibiotics because the drugs are not able to penetrate the plasma membrane. in addition, these bacteria may be able to transfer genes within cells while protected from the action of drugs. the primary mode by which virulence and antibiotic resistance genes are spread is bacterial conjugation. salmonellae have been shown to be competent for conjugation in the vacuoles of cultured mammalian ...200818765719
characterization of endemic shigella boydii strains isolated in iran by serotyping, antimicrobial resistance, plasmid profile, ribotyping and pulsed-field gel electrophoresis.shigellosis is one of the major causes of morbidity in children with diarrhea in iran. the present study was undertaken to characterize apparently sporadic shigella boydii strains isolated from pediatric patients in iran.200818755045
methods and tools for comparative genomics of foodborne pathogens.a comparison of genome sequences and of encoded proteins with the database of existing annotated sequences is a useful approach to understand the information at the genome level. here we demonstrate the utility of several dna and protein sequence comparison tools to interpret the information obtained from several genome projects. comparisons are presented between closely related strains of escherichia coli commensal isolates, different isolates of o157:h7, and shigella spp. it is expected that c ...200818713064
factors associated with acute diarrhoea in children in dhahira, oman: a hospital-based study.to elucidate the bacterial etiology of childhood diarrhoea in dhahira, 856 children < 12 years admitted for diarrhoea to ibri regional referral hospital from 2000 to 2002 were studied. the mean age was 2.4 (sd 2.3) years; the majority (92.9%) were < 5 years. bacterial etiology was found in 15.2% of cases; 10.6% due to shigella and 2.1% to salmonella. sh. sonnei was the commonest shigella serogroup isolated. salmonella infection was significantly associated with cramps, while shigella infection w ...200818720621
antimicrobial activity of extracts of edible wild and cultivated mushrooms against foodborne bacterial strains.the antimicrobial activity of aqueous, methanol, hexane, and ethyl acetate extracts from edible wild and cultivated mushrooms against nine foodborne pathogenic bacterial strains (escherichia coli o157:h7, salmonella enteritidis, shigella sonnei, vibrio parahaemolyticus, yersinia enterocolitica, bacillus cereus, clostridium perfringens, listeria monocytogenes, and staphylococcus aureus) was screened with a disk diffusion assay. twenty-nine of the 48 species tested had antimicrobial activity. meth ...200818724768
resistance to fluoroquinolones by the combination of target site mutations and enhanced expression of genes for efflux pumps in shigella flexneri and shigella sonnei strains isolated in korea.among 5938 clinical shigella spp. isolates, two s. flexneri strains were isolated as those resistant to fluoroquinolones based on the mics of the following antibiotics: ciprofloxacin, norfloxacin, ofloxacin, sparfloxacin and levofloxacin. s. flexneri 021787 had three substitutions, one in gyra (ser83leu) and two in parc (ser80ile and arg91gln). s. flexneri 021895 had four substitutions, two in gyra (ser83leu and asp87gly) and two in parc (ser80ile and arg91gln). the increased susceptibility of s ...200818727800
occurrence and characteristics of the cytolysin a gene in shigella strains and other members of the family enterobacteriaceae.cytolysin a (clya, hlye, shea) is a hemolytic pore-forming toxin found in escherichia coli and salmonella enterica serovars typhi and paratyphi a. in the present study, analysis of several shigella strains revealed that they harbor only nonfunctional clya gene copies that have been inactivated either by the integration of insertion sequence (is) elements (shigella dysenteriae, shigella boydii, and shigella sonnei strains) or by a frameshift mutation (shigella flexneri). shigella dysenteriae and ...200818754791
identification and functional characterization of gene components of type vi secretion system in bacterial genomes.a new secretion system, called the type vi secretion system (t6ss), was recently reported in vibrio cholerae, pseudomonas aeruginosa and burkholderia mallei. a total of 18 genes have been identified to be belonging to this secretion system in v. cholerae. here we attempt to identify presence of t6ss in other bacterial genomes. this includes identification of orthologous sequences, conserved motifs, domains, families, 3d folds, genomic islands containing t6ss components, phylogenetic profiles and ...200818698408
[htpg protein of shigella flexneri 2a strain 2457t evokes inflammatory response in mice].to analyze the function of htpg of s. flexneri 2a 2457t, we constructed an htpg deletion mutant and a recovery mutant.200818837368
structural and functional studies indicate that shigella vira is not a protease and does not directly destabilize microtubules.vira, an essential virulence factor in shigella disease pathogenesis, is involved in the uptake, motility, and cell-to-cell spread of shigella organisms within the human host. these functions have been attributed to a vira protease activity and a mechanism of microtubule destruction via tubulin degradation [yoshida, s., et al. (2006) science 314, 985-989]. we report functional and crystallographic data indicating a novel vira structure that lacks these activities but highlights the homology to t ...200818763811
topology and identification of critical residues of the o-acetyltransferase of serotype-converting bacteriophage, sf6, of shigella flexneri.the modification of the lps o-antigen, seen in the diverse serotypes of shigella flexneri is brought about by the glucosyltransferases (gtr) and the o-acetyltransferase (oac). in this study, we establish the membrane topology of oac using the dual reporter phoa-laczalpha. we have determined that oac is an integral membrane protein with 10 transmembrane regions. the hydrophilic n- and c-termini are oriented in the cytoplasm. functionally important cytoplasmic and periplasmic loops have also been ...200818755141
mutagenesis of the shigella flexneri autotransporter icsa reveals novel functional regions involved in icsa biogenesis and recruitment of host neural wiscott-aldrich syndrome protein.the icsa (virg) protein of shigella flexneri is a polarly localized, outer membrane protein that is essential for virulence. within host cells, icsa activates the host actin regulatory protein, neural wiskott-aldrich syndrome protein (n-wasp), which in turn recruits the arp2/3 complex, which nucleates host actin to form f-actin comet tails and initiate bacterial motility. linker insertion mutagenesis was undertaken to randomly introduce 5-amino-acid in-frame insertions within icsa. forty-seven l ...200818456802
a five-year antimicrobial resistance pattern of shigella isolated from stools in the gondar university hospital, northwest ethiopia.shigellosis is a global health problem. however, developing countries, where there is poor hygiene and unsafe water supplies, are especially affected. in the last two decades shigella isolates have become increasingly resistant to many commonly used drugs. we investigated the antibiotic susceptibility pattern of shigella isolated from stool specimens processed over five years in the bacteriology laboratory of the university of gondar teaching hospital in northwest ethiopia. stool specimens were ...200818302868
maturation of paneth cells induces the refractory state of newborn mice to shigella infection.the intestinal tract of adult mice is naturally resistant to infection by shigella, the causative agent of bacillary dysentery in humans. conversely, newborn mice are highly susceptible to intragastric shigella infection and develop inflammatory lesions of the jejunal mucosa, very similar to those observed in the colon of dysenteric patients. however, the susceptibility period is short and one week after birth, animals have acquired a status of resistance characteristic of adult animals. to iden ...200818354217
differential expression of ompc and ompf in multidrug-resistant shigella dysenteriae and shigella flexneri by aqueous extract of aegle marmelos, altering its susceptibility toward beta-lactam antibiotics.steadily increasing resistance among shigella to beta-lactams, aminoglycosides, and tetracycline has compromised the utility of these commonly used antimicrobial agents. also, undesirable side effects of certain antibiotics have triggered immense interest in search of alternative therapies using medicinal plants. one such medicinal plant used since ancient times to cure diarrhea is aegle marmelos. the present study exemplifies the susceptibility of beta-lactam-resistant shigella dysenteriae and ...200818358664
on-line monitoring of microbial volatile metabolites by proton transfer reaction-mass spectrometry.a method for analysis of volatile organic compounds (vocs) from microbial cultures was established using proton transfer reaction-mass spectrometry (ptr-ms). a newly developed sampling system was coupled to a ptr-ms instrument to allow on-line monitoring of vocs in the dynamic headspaces of microbial cultures. the novel ptr-ms method was evaluated for four reference organisms: escherichia coli, shigella flexneri, salmonella enterica, and candida tropicalis. headspace vocs in sampling bottles con ...200818245241
traveler's myopericarditis.colitis caused by shigella is an uncommon etiology of infectious diarrhea in developed countries, usually presenting as traveler's diarrhea. aside from clinical intestinal manifestations, shigellosis can present with a wide variety of extra-intestinal symptoms. we present the case of a 38-year-old man with diarrhea, fever, and chest pain that started after a holiday in cape verde (africa). blood samples revealed an increase in cardiac enzymes. an electrocardiogram revealed a widespread elevation ...200818249314
phase 1 clinical trial of live attenuated shigella dysenteriae type-1 deltaicsa deltaent deltafep deltastxa:hgr oral vaccine sc599 in healthy human adult volunteers.twenty-eight adults received between 10(2) and 10(8)colony forming units of live shigella dysenteriae type-1 vaccine sc599, attenuated by deletion of invasion (icsa), iron chelation (ent, fep) and shiga toxin a-subunit (stxa) genes, followed by ciprofloxacin on day 4. dose-independent diarrhea or change in bowel habit was seen in 3 subjects, without dysentery, vaccinaemia or serious adverse events. hematology and biochemical parameters were unchanged. doses of 10(5) or greater induced dose-indep ...200818207287
estimation of the diagnostic accuracy of the inva-gene-based pcr technique and a bacteriological culture for the detection of salmonella spp. in caecal content from slaughtered pigs using bayesian analysis.the goal of this study was to estimate the accuracy of the inva-gene-based polymerase chain reaction (pcr) and a culture technique based on pre-enrichment with buffered peptone water, three selective enrichment media (selenite, tetrathionate and rappaport-vassiliadis broths) and four selective, solid media (xylose-lysine-tergitol-4, salmonella/shigella, hekton-enteric and macconkey), for the detection of salmonella organisms from caecal samples from slaughter pigs. for this purpose a latent-clas ...200818234030
an intersubunit active site between supercoiled parallel beta helices in the trimeric tailspike endorhamnosidase of shigella flexneri phage sf6.sf6 belongs to the podoviridae family of temperate bacteriophages that infect gram-negative bacteria by insertion of their double-stranded dna. they attach to their hosts specifically via their tailspike proteins. the 1.25 a crystal structure of shigella phage sf6 tailspike protein (sf6 tsp) reveals a conserved architecture with a central, right-handed beta helix. in the trimer of sf6 tsp, the parallel beta helices form a left-handed, coiled-beta coil with a pitch of 340 a. the c-terminal domain ...200818462681
high rate of resistance to locally used antibiotics among enteric bacteria from children in northern ghana.information on antimicrobial susceptibility of bacterial pathogens is scarce in resource-poor settings. we determined the susceptibility of bacterial enteric pathogens and faecal escherichia coli isolates obtained from children in urban tamale, northern ghana, to antibiotics widely used in the that area [ampicillin or amoxicillin, trimethoprim/sulfamethoxazole (sxt) and chloramphenicol] and to alternative drugs.200818356156
immunological evidence for functional rather than structural mimicry by a shigella flexneri y polysaccharide-mimetic peptide.an approach to vaccine design is the use of molecules that mimic the immunogenic element of interest. in this context, the interaction of mdwnmhaa, a peptide mimic of the shigella flexneri y o polysaccharide (ps), with an anti-carbohydrate monoclonal antibody, as studied previously by x-ray crystallography, suggested the presence of functional rather than structural mimicry and a bound peptide conformation that was not represented significantly in the free-ligand ensemble. the antibody response ...200818463226
antimicrobial susceptibility of shigella isolates in eight asian countries, 2001-2004.shigellosis is a major health problem in developing countries, causing 91 million episodes and 414,000 deaths in asia annually. because of increasing trends towards drug resistance, this study was undertaken to monitor local resistance patterns of shigella isolates from 8 asian countries.200818473096
[antigenic polysaccharides of bacteria: 40. the structures of o-specific polysaccharides from shigella dysenteriae types 3 and 9 and s. boydii type 4 revised by nmr spectroscopy].the reported structures of o-specific polysaccharides from three standard strains of shigella bacteria were corrected by modern nmr techniques. the revisions concerned the configuration of the o-glycoside linkage (s. dysenteriae type 3, structure 1), the positions of monosaccharide residue glycosylation and acetylation by pyruvic acid (s. dysenteriae type 9, structure 2), and the attachment position of the side monosaccharide chain (s. boydii type 4, structure 3) [struxture in text].200818365747
analysis of rho-gtpase mimicry by a family of bacterial type iii effector proteins.microbial pathogens may hijack the actin cytoskeleton machinery to facilitate actin-based motility, cellular invasion, and intracellular trafficking through the endocytic pathway. of particular interest has been a large class of virulence factors collectively termed the type iii "effector" proteins. following contact with a eukaryotic cell, gram-negative bacterial pathogens employ a dedicated protein secretion apparatus termed type iii to translocate effector proteins into the cellular cytoplasm ...200818374161
coiled-coil regions play a role in the function of the shigella flexneri o-antigen chain length regulator wzzphs2.regulation of the length of the o-antigen (oag) chain attached to lps in shigella flexneri is important for virulence and is dependent on the inner-membrane protein wzz. a lack of high-resolution structural data for wzz has hampered efforts so far to correlate mutations affecting function of wzz with structure and describe a mechanism for chain length regulation. here we have used secondary structure prediction to show that the periplasmic domain of the wzz(phs2) protein has three regions of sig ...200818375803
post-infectious functional gastrointestinal disorders in children.to investigate the development of functional gastrointestinal disorders (fgids) after an episode of acute bacterial gastroenteritis (age) in children.200818492522
ospf directly attenuates the activity of extracellular signal-regulated kinase during invasion by shigella flexneri in human dendritic cells.shigella spp., gram-negative pathogenic bacteria, deliver various effector molecules into the host cell cytoplasm through their type iii secretion system to facilitate their invasive process and control the host innate immune responses. although the function of these effectors is well characterized in epithelial cells during shigella infection, it has not been elucidated in the dendritic cell (dc), a major antigen presenting cell playing an important role in the initiation of immune responses. i ...200818378312
[shigella spp. infections in getafe hospital between 2001 and 2006].shigella spp. is a bacterium that frequently causes diarrhoea in underdeveloped countries, but not so much in spain, where it has been published that its incidence has decreased in the last few years.200818559201
a global modulatory role for the yersinia enterocolitica h-ns protein.the h-ns protein plays a significant role in the modulation of gene expression in gram-negative bacteria. whereas isolation and characterization of hns mutants in escherichia coli, salmonella and shigella represented critical steps to gain insight into the modulatory role of h-ns, it has hitherto not been possible to isolate hns mutants in yersinia. the hns mutation is considered to be deleterious in this genus. to study the modulatory role of h-ns in yersinia we circumvented hns lethality by ex ...200818451036
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