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[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
[glycosphingolipids gb3 and igb3. in vivo roles in hemolytic-uremic syndrome and inkt cell function].the glycosphingolipids globotrihexosylceramide (gb3, cd77) and isoglobotrihexosylceramide (igb3) are isomers differing only in one glycosidic bond and have been implicated in several processes of the innate and adaptive immune system.200818810447
mechanisms of infectious diarrhea.infectious diarrhea is an important public health problem worldwide. research has provided new insights into the mechanisms of diarrhea caused by various pathogens that are classified as noninflammatory, inflammatory or invasive. these three groups of organisms cause two diarrheal syndromes--noninflammatory diarrhea and inflammatory diarrhea. the noninflammatory diarrheas are caused by enterotoxin-producing organisms such as vibrio cholerae and enterotoxigenic escherichia coli, or by viruses tha ...200818813221
subproteomic tools to increase genome annotation complexity.comprehensive and precise annotations of short protein-coding genes are always a challenging task. here we propose a new design to facilitate the characterization of previously overlooked short protein-coding genes by integrating a shotgun proteomics method and oligonucleotide array analysis. using shigella flexneri as a model, we validate 163 annotated orfs and 51 hypothetical or putative transcripts at the protein level, and discover four novel short orfs. this strategy will contribute signifi ...200818814329
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
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
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
shigellosis in puducherry. 200818765885
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
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
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
antibacterial antibodies for some enterobacteria in sera of patients with reactive arthritis and other rheumatoid diseases.the presence of the specific antibodies for some enterobacteria--yersinia, salmonella and shigella was investigated in patients hospitalized in the period 2000-2007 with reactive arthritis and other rheumatoid diseases. the antibacterial antibodies in the diagnosis titres were found in 172 out of 1102 (15.6%) patients. increased antibodies levels to yersinia were detected in the sera from 113 (65.7%) of the 172 patients, for shigella in 47 (27.3%) and for salmonella in 12 (7.0%) cases. from all ...200819284164
coliforms and prevalence of escherichia coli and foodborne pathogens on minimally processed spinach in two packing plants.minimally processed spinach has been recently associated with outbreaks of foodborne illnesses. this study investigated the effect of commercial minimal processing of spinach on the coliform and escherichia coli counts and the prevalence of e. coli o157:h7, salmonella, shigella spp., and listeria monocytogenes on two types of spinach before and after minimal processing. a total of 1,356 spinach samples (baby spinach, n = 574; savoy spinach, n = 782) were collected daily in two processing plants ...200819244890
intestinal bacterial and parasitic infections among food handlers in a tertiary care hospital of north india.intestinal infection is still an important public health problem in developing countries like india. food handlers may be infected by a wide range of enteropathogens and have been implicated in the transmission of many infections to the public in the community and to patients in hospitals.200819323089
[typing of shigella sonnei strains isolated in some provinces of turkey using antimicrobial resistance and pulsed field gel electrophoresis methods].shigella species may lead to large epidemics owing to their low infective doses and frequent transmission from person to person with high secondary attack rates. shigella sonnei is one of the most prevalent causative agent of infectious gastroenteritis in developing and developed countries and it is the most frequently reported shigella serotype from turkey in recent years. the aim of this study was to determine the types of s. sonnei strains isolated in different provinces of turkey [in marmara ...200819149077
[evaluation of laboratory diagnosis of the first norovirus outbreak in turkey in 2008].norovirus (nov) is one of the most prominent agents of gastroenteritis and water/food-borne outbreaks affecting all of the age groups in the world. as the identification of the etiologic agent is important during gastroenteritis outbreaks, it is recommended to combine two different methods for rapid and reliable laboratory diagnosis of nov. although nov outbreaks have been observed in many different countries of the world, there was no report on "nov outbreak" in turkey till 2008 due to the abse ...200819149082
interactions of the intestinal epithelium with the pathogen and the indigenous microbiota: a three-way crosstalk.the mucosal surfaces of the gastrointestinal tract harbor a vast number of commensal microbiota that have coevolved with the host, and in addition display one of the most complex relationships with the host. this relationship affects several important aspects of the biology of the host including the synthesis of nutrients, protection against infection, and the development of the immune system. on the other hand, despite the existence of several lines of mucosal defense mechanisms, pathogenic org ...200819259328
microbiological quality and safety of rastrineobola argentea retailed in kisumu town markets, kenya.to investigate faecal contamination and safety of rastrineobola argentea sold in retail markets in kisumu town.200819537428
antibacterial, antifungal and cytotoxic activities of amblyone isolated from amorphophallus campanulatus.to assess the in vitro antibacterial, antifungal and cytotoxic activities of amblyone, a triterpenoid isolated from amorphophallus campanulatus (roxb).200821264161
differential activation of human tlr4 by escherichia coli and shigella flexneri 2a lipopolysaccharide: combined effects of lipid a acylation state and tlr4 polymorphisms on signaling.the lipid a of lps activates tlr4 through an interaction with myeloid differentiation protein-2 (md-2) and the degree of lipid a acylation affects tlr4 responsiveness. two tlr4 single nucleotide polymorphisms (asp299gly and thr399ile) have been associated with lps hyporesponsiveness. we hypothesized that the combination of hypoacylation and these single nucleotide polymorphisms would exhibit a compounded effect on tlr4 signaling. hek293t transfectants expressing wild-type or polymorphic tlr4 wer ...200818178854
a comparative synteny map of burkholderia species links large-scale genome rearrangements to fine-scale nucleotide variation in prokaryotes.genome rearrangement events, including inversions and translocations, are frequently observed across related microbial species, but the impact of such events on functional diversity is unclear. to clarify this relationship, we compared 4 members of the gram-negative burkholderia family (burkholderia pseudomallei, burkholderia mallei, burkholderia thailandensis, and burkholderia cenocepacia) and identified a core set of 2,590 orthologs present in all 4 species (metagenes). the metagenes were orga ...200818162473
role of escherichia coli in acute diarrhoea in tribal preschool children of central india.five hundred and eighty preschool children belonging to tribal areas of madhya pradesh were followed up daily for the presence of diarrhoea for a period of 1 year. in all, 1236 episodes of diarrhoea were recorded with an average of 2.13 episodes per child per year. stool samples were collected during 780 episodes. they were cultured to isolate escherichia coli as well as non-e. coli enteropathogens. ten different genes were detected to identify all diarrhoeagenic e. coli using multiplex polymera ...200818173783
diarrheagenic escherichia coli and shigella strains isolated from children in a hospital case-control study in hanoi, vietnam.this case-control study detected and characterized shigella and diarrheagenic escherichia coli (dec) types among vietnamese children less than 5 years old. in 249 children with diarrhea and 124 controls, shigella spp. was an important cause of diarrhea (p < 0.05). we used multiplex pcr and dna probes to detect enteroinvasive e. coli (eiec), enteroaggregative e. coli (eaggec), enteropathogenic e. coli (epec), attaching and effacing e. coli (a/eec), verocytotoxin-producing e. coli (vtec), and ente ...200818174300
full structural characterization of shigella flexneri m90t serotype 5 wild-type r-lps and its delta galu mutant: glycine residue location in the inner core of the lipopolysaccharide.shigella flexneri is a gram-negative bacterium responsible for serious enteric infections that occur mainly in the terminal ileum and colon. high interest in shigella, as a human pathogen, is driven by its antibiotic resistance and the necessity to develop a vaccine against its infections. vaccines of the last generation use carbohydrate moieties of the lipopolysaccharide as probable candidates. for this reason, the primary structure of the core oligosaccharide from the r-lps produced by s. flex ...200818174310
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
involvement of rna-binding protein hfq in the post-transcriptional regulation of inve gene expression in shigella sonnei.the temperature-dependent regulation of shigella virulence genes is believed to be accomplished at the transcriptional stage by the regulators virf and inve. several lines of evidence herein described indicate that post-transcriptional regulation of inve expression plays a key role in the temperature-dependent regulation of virulence gene expression: (i) a considerable amount of inve mrna continues to be transcribed under low temperature conditions, where the production of inve protein is tightl ...200818156173
cytoplasmic targeting of ipac to the bacterial pole directs polar type iii secretion in shigella.type iii secretion (t3s) systems are largely used by pathogenic gram-negative bacteria to inject multiple effectors into eukaryotic cells. upon cell contact, these bacterial microinjection devices insert two t3s substrates into host cell membranes, forming a so-called 'translocon' that is required for targeting of type iii effectors in the cell cytosol. here, we show that secretion of the translocon component ipac of invasive shigella occurs at the level of one bacterial pole during cell invasio ...200818188151
bacterial actin assembly requires toca-1 to relieve n-wasp autoinhibition.actin polymerization in the mammalian cytosol can be locally activated by mechanisms that relieve the autoinhibited state of n-wasp, an initiator of actin assembly, a process that also requires the protein toca-1. several pathogenic bacteria, including shigella, exploit this host feature to infect and disseminate efficiently. the shigella outer membrane protein icsa recruits n-wasp, which upon activation at the bacterial surface mediates localized actin polymerization. the molecular role of toca ...200818191793
antibacterial activities and cytotoxicity of terpenoids isolated from spirostachys africana.spirostachys africana sond. stem bark is used traditionally for the treatment of diarrhoea and dysentery in limpopo province of south africa. bioassay-guided fractionation of ethanolic extract from bark of spirostachys africana led to the isolation of four known compounds, two triterpenoids, compound 1 [d-friedoolean-14-en-oic acid (3-acetyl aleuritolic acid)] and compound 2 (lupeol), and two diterpenes, compound 3 [ent-2,6alpha-dihydroxy-norbeyer-1,4,15-trien-3-one (diosphenol 2)] and compound ...200818191928
the chaperone ipgc copurifies with the virulence regulator mxie.the expression of a subset of shigella flexneri virulence genes is dependent upon a cytoplasmic chaperone, ipgc, and an activator from the arac/xyls family, mxie. in this paper, we report that the chaperone forms a specific and stable heteromer with mxie.200818192384
role and regulation of iron-sulfur cluster biosynthesis genes in shigella flexneri virulence.shigella flexneri, a causative agent of bacterial dysentery, possesses two predicted iron-sulfur cluster biosynthesis systems called suf and isc. s. flexneri strains containing deletion mutations in the entire suf operon (ur011) or the iscsua genes (ur022) were constructed. both mutants were defective in surviving exposure to oxidative stress. the suf mutant showed growth that was comparable to that of the parental strain in both iron-replete and iron-limiting media; however, the isc mutant show ...200818195027
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
a comparison of self-reported joint symptoms following infection with different enteric pathogens: effect of hla-b27.we conducted a case-case comparison study to estimate the attack-rate of reactive joint pain (jprea) following intestinal infections, and evaluated whether the susceptibility and severity of joint symptoms was associated with the tissue-type hla-b27.200818203313
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
a functional genomic yeast screen to identify pathogenic bacterial proteins.many bacterial pathogens promote infection and cause disease by directly injecting into host cells proteins that manipulate eukaryotic cellular processes. identification of these translocated proteins is essential to understanding pathogenesis. yet, their identification remains limited. this, in part, is due to their general sequence uniqueness, which confounds homology-based identification by comparative genomic methods. in addition, their absence often does not result in phenotypes in virulenc ...200818208325
nitrate and bacterial contamination in well waters in vinh phuc province, vietnam.measurements were made of the nitrate concentration and bacterial contamination of groundwater samples taken from both dug wells and bores in the commune of hop thinh', in the administrative district of vinh phuc, vietnam. a significant number (18%) of samples had nitrate concentrations in excess of the who guideline value for drinking water of 50 mg l(-1), with a higher proportion in the dug wells (29%) than the bores (3.8%). high concentrations of thermotolerant coliforms were found in many of ...200818209289
selection and validation of a multilocus variable-number tandem-repeat analysis panel for typing shigella spp.the shigella genus has historically been separated into four species, based on biochemical assays. the classification within each species relies on serotyping. recently, genome sequencing and dna assays, in particular the multilocus sequence typing (mlst) approach, greatly improved the current knowledge of the origin and phylogenetic evolution of shigella spp. the shigella and escherichia genera are now considered to belong to a unique genomospecies. multilocus variable-number tandem-repeat (vnt ...200818216214
nlrx1 is a mitochondrial nod-like receptor that amplifies nf-kappab and jnk pathways by inducing reactive oxygen species production.nod-like receptors (nlrs) are a family of intracellular sensors of microbial- or danger-associated molecular patterns. here, we report the identification of nlrx1, which is a new member of the nlr family that localizes to the mitochondria. nlrx1 alone failed to trigger most of the common signalling pathways, including nuclear factor-kappab (nf)-kappab- and type i interferon-dependent cascades, but could potently trigger the generation of reactive oxygen species (ros). importantly, nlrx1 synergis ...200818219313
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
the origin of a novel gene through overprinting in escherichia coli.overlapped genes originate by a) loss of a stop codon among contiguous genes coded in different frames; b) shift to an upstream initiation codon of one of the contiguous genes; or c) by overprinting, whereby a novel open reading frame originates through point mutation inside an existing gene. although overlapped genes are common in viruses, it is not clear whether overprinting has led to new genes in prokaryotes.200818226237
cmy-2-type plasmid-mediated ampc beta-lactamase finally emerging in argentina. 200818242960
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
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
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
muramylpeptide shedding modulates cell sensing of shigella flexneri.bacterial infections trigger the activation of innate immunity through the interaction of pathogen-associated molecular patterns (pamps) with pattern recognition molecules (prms). the nucleotide-binding oligomerization domain (nod) proteins are intracellular prms that recognize muramylpeptides contained in peptidoglycan (pgn) of bacteria. it is still unclear how nod1 physically interacts with pgn, a structure internal to the gram-negative bacterial envelope. to contribute to the understanding of ...200818042252
the versatility of shigella effectors.when shigella infect the intestinal epithelium, they deliver several effectors through the type iii secretion system (t3ss) into the surrounding space and directly into the host-cell cytoplasm, where they can mimic and usurp host cellular functions or subvert host-cell signalling pathways and the immune response. although bacterial strategies and mechanisms of infection vary greatly, recent studies of shigella effectors have revealed that shigella possess a highly evolved strategy for infection.200818059288
saccharomyces boulardii interferes with shigella pathogenesis by postinvasion signaling events.saccharomyces boulardii is gaining in popularity as a treatment for a variety of diarrheal diseases as well as inflammatory bowel disease. this study was designed to examine the effect of this yeast on infection by shigella flexneri, a highly infectious and human host-adapted enteric pathogen. we investigated key interactions between the bacteria and host cells in the presence of the yeast in addition to a number of host responses including proinflammatory events and markers. although the presen ...200818032477
activities of the frog skin peptide, ascaphin-8 and its lysine-substituted analogs against clinical isolates of extended-spectrum beta-lactamase (esbl) producing bacteria.extended-spectrum beta-lactamase (esbl)-producing gram-negative bacteria are becoming increasingly prevalent and their antibiotic resistance necessitates novel therapeutic intervention. ascaphin-8 is a cationic alpha-helical peptide that shows broad-spectrum antibacterial activity but is also toxic to human erythrocytes (lc(50)= 55 microm). this study assesses the activity of ascaphin-8, and a series of l-lysine-substituted analogs, against a range of clinical isolates of esbl-producing bacteria ...200818068868
quinolone resistance among shigella spp. isolated from travellers returning from india.among 200 isolates of shigella from patients with travellers' diarrhoea, 12 isolates (four isolated in 1995-2000 and eight in 2001-2004) exhibited quinolone resistance. nine of these isolates originated from india. these resistant isolates had at least one amino-acid substitution in gyra. quinolone resistance is increasing in shigella spp. causing travellers' diarrhoea, and particularly among isolates causing diarrhoea in travellers returning from india.200818076667
isolation and purification of enterocin e-760 with broad antimicrobial activity against gram-positive and gram-negative bacteria.strain nrrl b-30745, isolated from chicken ceca and identified as enterococcus durans, enterococcus faecium, or enterococcus hirae, was initially identified as antagonistic to campylobacter jejuni. the isolate produced a 5,362-da bacteriocin (enterocin) that inhibits the growth of salmonella enterica serovar enteritidis, s. enterica serovar choleraesuis, s. enterica serovar typhimurium, s. enterica serovar gallinarum, escherichia coli o157:h7, yersinia enterocolitica, citrobacter freundii, klebs ...200818086839
systemic pharmacokinetics of rifaximin in volunteers with shigellosis.rifaximin is an oral antibiotic indicated for treatment of traveler's diarrhea. rifaximin pharmacokinetics were evaluated in individuals challenged with shigella flexneri. peak plasma rifaximin concentrations were low after nine consecutive doses, and no accumulation was observed. rifaximin serum levels were minimal and similar to those previously reported in studies of healthy volunteers.200818086855
antimicrobial activity of an endophytic xylaria sp.yx-28 and identification of its antimicrobial compound 7-amino-4-methylcoumarin.an endophytic xylaria sp., having broad antimicrobial activity, was isolated and characterized from ginkgo biloba l. from the culture extracts of this fungus, a bioactive compound p3 was isolated by bioactivity-guided fractionation and identified as 7-amino-4-methylcoumarin by nuclear magnetic resonance, infrared, and mass spectrometry spectral data. the compound showed strong antibacterial and antifungal activities in vitro against staphylococcus aureus [minimal inhibitory concentrations (mic) ...200818092158
phenotypic and molecular characterization of tem-116 extended-spectrum beta-lactamase produced by a shigella flexneri clinical isolate from chickens.extended-spectrum beta-lactamases (esbls) produced by a clinical isolate of shigella flexneri from chickens were detected with confirmatory phenotypic tests of the clinical and laboratory standards institute, and minimum inhibitory concentrations of several antibacterial drugs against the isolate were determined by the twofold dilution method. the genotype and subtype of the esbl-producing s. flexneri isolate were identified by pcr amplifying of esbl genes and dna sequencing analysis. the result ...200818093137
isolation and antibiotic susceptibility of salmonella and shigella strains isolated from children in gaza, palestine from 1999 to 2006.diarrhea and acute gastroenteritis are among the leading causes of illnesses and death in infants and children throughout the world, especially in developing countries, globally, salmonella and shigella remain the major contributors to acute enteric infections and diarrhea.200817854424
role of shigella infection in endometriosis: a novel hypothesis.endometriosis is the presence of endometrial cells and stroma at ectopic sites outside the uterine cavity. the natural history of endometriosis is uncertain, its etiology unknown, the clinical presentation inconsistent, diagnosis difficult and the treatment poorly standardized. it causes significant morbidity due to pelvic pain and infertility among 15-25% of women during their reproductive age. the benign disease causes peritoneal inflammation, fibrosis, adhesions and ovarian cysts but displays ...200817888583
clostridium difficile: an under-recognized cause of reactive arthritis?reactive arthritis usually presents as a sterile, inflammatory, asymmetric oligoarthritis, affecting large lower extremity joints. extra-articular features (conjunctivitis, uveitis, enthesopathy, urethritis, balanitis, keratoderma blenorrhagicum) may occur. common causes of enteric reactive arthritis are preceding infections attributable to salmonella, shigella, campylobacter, and yersinia. in contrast, clostridium difficile is an uncommon cause of reactive arthritis, with only approximately 40 ...200817902012
identification of newly recognized serotype 1c as the most prevalent shigella flexneri serotype in northern rural vietnam.we investigated the identity of 37 shigella flexneri strains that had previously been isolated from northern rural vietnam (son tay province) and described as untypable. twenty-four isolates reacted with masf 1c, a monoclonal antibody specific for s. flexneri serotype 1c. a further ten untypable isolates were found to be rough mutants (no longer expressing o-antigen) that were derived from serotype 1c strains. pulsed-field gel electrophoresis demonstrated that these strains consisted of many dif ...200817922932
development of a tripartite vector system for live oral immunization using a gram-negative probiotic carrier.the mucosa represents the primary target site and thus the first barrier for most microbial pathogens. nevertheless, nearly all present-day vaccines are applied by an invasive route, target the systemic immune system, and do not confer efficient mucosal protection. currently, mucosal immunity can only be achieved by the delivery of antigens via the mucosal route. therefore, multiple efforts are under way to develop mucosal vaccines and particularly live oral vaccines as these would confer consid ...200817936683
a role for nod-like receptors in autophagy induced by shigella infection.shigella infection, the cause of bacillary dysentery, induces caspase-1 activation and cell death in macrophages, but the precise mechanisms remain poorly understood. in our recent study, we presented evidence 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 contai ...200817932464
[hemolytic and uremic syndrome in the child].hemolytic and uremic syndrome (hus) is characterized by the association of hemolytic anemia with sckizocytes, thrombopenia and renal involvement secondary to thrombotic microangiopathy. the typical form is the most frequent in children occurring after an episode of diarrhea caused by escherichia coli. other microorganisms may be responsible for hus such as shigella dysenteriae or streptococcus pneumoniae. acute renal failure is reversible in most cases, but long-term renal sequelae are seen in o ...200817964233
synthesis, characterization and antibacterial activity of cobalt(iii) complexes with pyridine-amide ligands.the ligands 2-(n-(x-pyridyl)carbamoyl)pyridine (x=2, 3 or 4 for hl1-hl3, respectively) and 2,6-bis(n-(y-pyridyl)carbamoyl)pyridine (y=2, 3 or 4 for h2l4-h2l6, respectively) in their mono- and di-deprotonated forms have been used to synthesize kinetically stable cobalt(iii) compounds [co(l1-3)3] (1-3) and na[co(l4-6)2] (4-6), respectively. the co(iii) ion is in octahedral environment and is surrounded by three bidentate ligands in complexes 1-3 and two tridentate ligands in complexes 4-6. ligands ...200817959275
the pattern-recognition molecule nod1 is localized at the plasma membrane at sites of bacterial interaction.the pattern-recognition molecule nod1 is a critical sensor for bacterial derived diaminopimelic acid-containing peptidoglycan fragments which induces innate immune responses in epithelial cells. here we report the subcellular localization of this protein in human epithelial cells. nod1 is localized in the cytosol and at the plasma membrane in human cells. this membrane association is dependent on the integrity of the protein, on its signalling capacity and on an intact actin cytoskeleton. signal ...200817970764
evaluating burkholderia pseudomallei bip proteins as vaccines and bip antibodies as detection agents.burkholderia pseudomallei is a biothreat agent and an important natural pathogen, causing melioidosis in humans and animals. a type iii secretion system (ttss-3) has been shown to be critical for virulence. because ttss components from other pathogens have been used successfully as diagnostic agents and as experimental vaccines, it was investigated whether this was the case for bipb, bipc and bipd, components of b. pseudomallei's ttss-3. the sequences of bipb, bipc and bipd were found to be high ...200817995960
bacterial and fungal infections among diagnostic laboratory workers: evaluating the risks.accidental infections acquired in the laboratory environment are not reportable in a formal forum outside the institution, and therefore, there is little opportunity to evaluate such occurrences and learn from them. we evaluated voluntary responses from 88 facilities, 53 large hospitals (>200 beds) or academic institutions, 32 smaller facilities (<200 beds), and 3 national reference diagnostic laboratories. thirty-eight of the laboratories (43%), 15 large and 23 small facilities, reported no kno ...200817997259
enteropathogen resource integration center (eric): bioinformatics support for research on biodefense-relevant enterobacteria.eric, the enteropathogen resource integration center (www.ericbrc.org), is a new web portal serving as a rich source of information about enterobacteria on the niaid established list of select agents related to biodefense-diarrheagenic escherichia coli, shigella spp., salmonella spp., yersinia enterocolitica and yersinia pestis. more than 30 genomes have been completely sequenced, many more exist in draft form and additional projects are underway. these organisms are increasingly the focus of st ...200817999997
priming of cd4+ t cells with porin of shigella dysenteriae activates the cells toward type 1 polarization.macrophages treated with porin of shigella dysenteriae were potent stimulators of naive t(h) cells since the porin-pulsed macrophages strongly proliferated the t cells and up-regulated the activation molecules cd69 and cd25 on cd4(+) t cells in allogeneic mixed leukocyte reaction. immunization of c57bl/6 mice with porin selectively induced the intracellular expression and release of ifn-gamma and had no effect on il-4 expression. in parallel to the predominant release of the t(h)1 cytokine ifn-g ...200818003602
shiga toxin 1 induces apoptosis through the endoplasmic reticulum stress response in human monocytic cells.shiga toxins (stxs) expressed by the enteric pathogens shigella dysenteriae 1 and enterohaemorrhagic escherichia coli are potent protein synthesis inhibitors. shiga toxins have also been shown to induce apoptosis in epithelial, endothelial and monocytic cells. the precise relationship between protein synthesis inhibition and induction of apoptosis is not known. we show that stimulation of the myelogenous leukaemia cell line thp-1 with purified stx1 induced the endoplasmic reticulum (er) stress r ...200818005243
the nlee/ospz family of effector proteins is required for polymorphonuclear transepithelial migration, a characteristic shared by enteropathogenic escherichia coli and shigella flexneri infections.enteropathogenic escherichia coli (epec) and shigella flexneri are human host-specific pathogens that infect intestinal epithelial cells. however, each bacterial species employs a different infection strategy within this environmental niche. epec attaches to the apical surface of small intestine enterocytes, causing microvillus effacement and rearrangement of the host cell cytoskeleton beneath adherent bacteria. in contrast, s. flexneri invades the large intestine epithelium at the basolateral m ...200817984206
contribution of the sitabcd, mnth, and feob metal transporters to the virulence of avian pathogenic escherichia coli o78 strain chi7122.the roles of sitabcd, mnth, and feob metal transporters in the virulence of avian pathogenic escherichia coli (apec) o78 strain chi7122 were assessed using isogenic mutants in chicken infection models. in a single-strain infection model, compared to chi7122, the deltasit strain demonstrated reduced colonization of the lungs, liver, and spleen. complementation of the deltasit strain restored virulence. in a coinfection model, compared to the virulent apec strain, the deltasit strain demonstrated ...200818025097
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
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
containment of tumor-colonizing bacteria by host neutrophils.administration of facultative anaerobic bacteria like salmonella typhimurium, shigella flexneri, and escherichia coli to tumor-bearing mice leads to a preferential accumulation and proliferation of the microorganisms within the solid tumor. until now, all known tumor-targeting bacteria have shown poor dissemination inside the tumors. they accumulate almost exclusively in large necrotic areas and spare a rim of viable tumor cells. interestingly, the bacteria-containing necrotic region is separate ...200818413765
development of a travelers' diarrhea vaccine for the military: how much is an ounce of prevention really worth?infectious diarrhea is one of the many threats to the deployed military, and given limited resources, a decision to pursue a vaccine acquisition strategy should be based on best evidence that weighs costs and benefits compared to alternatives. an economic model was developed to estimate the marginal cost to avert a duty day lost due to diarrhea for a vaccine acquisition strategy compared to current clinical management, for both multiplex and pathogen-specific vaccines. vaccines against campyloba ...200818417259
a pharmacokinetic study of enrofloxacin and its active metabolite ciprofloxacin after oral and intramuscular dosing of enrofloxacin in rhesus monkeys (macaca mulatta).enrofloxacin is used for treating shigellosis in non-human primates; however, there are no reports describing its pharmacokinetics in rhesus monkeys. pharmacokinetic data in intended target species (rhesus) help to determine the proper dose regimen. blood levels of enrofloxacin and ciprofloxacin (enrofloxacin's active metabolite), were determined after either intramuscular or oral dosing of enrofloxacin for 7 days in a cross-over study. levels of both antibiotics were determined by solid phase e ...200818384536
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
human-derived probiotic lactobacillus reuteri demonstrate antimicrobial activities targeting diverse enteric bacterial pathogens.lactobacillus reuteri is a commensal-derived anaerobic probiotic that resides in the human gastrointestinal tract. l. reuteri converts glycerol into a potent broad-spectrum antimicrobial compound, reuterin, which inhibits the growth of gram-positive and gram-negative bacteria. in this study, we compared four human-derived l. reuteri isolates (atcc 55730, atcc pta 6475, atcc pta 4659 and atcc pta 5289) in their ability to produce reuterin and to inhibit the growth of different enteric pathogens i ...200818396068
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
the emergence and fate of horizontally acquired genes in escherichia coli.bacterial species, and even strains within species, can vary greatly in their gene contents and metabolic capabilities. we examine the evolution of this diversity by assessing the distribution and ancestry of each gene in 13 sequenced isolates of escherichia coli and shigella. we focus on the emergence and demise of two specific classes of genes, orfans (genes with no homologs in present databases) and hops (genes with distant homologs), since these genes, in contrast to most conserved ancestral ...200818404206
structure and genetics of shigella o antigens.this review covers the o antigens of the 46 serotypes of shigella, but those of most shigella flexneri are variants of one basic structure, leaving 34 shigella distinct o antigens to review, together with their gene clusters. several of the structures and gene clusters are reported for the first time and this is the first such group for which structures and dna sequences have been determined for all o antigens. shigella strains are in effect escherichia coli with a specific mode of pathogenicity ...200818422615
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
virulent shigella flexneri subverts the host innate immune response through manipulation of antimicrobial peptide gene expression.antimicrobial factors are efficient defense components of the innate immunity, playing a crucial role in the intestinal homeostasis and protection against pathogens. in this study, we report that upon infection of polarized human intestinal cells in vitro, virulent shigella flexneri suppress transcription of several genes encoding antimicrobial cationic peptides, particularly the human beta-defensin hbd-3, which we show to be especially active against s. flexneri. this is an example of targeted ...200818426984
ctx-m-15-producing shigella sonnei strain from a czech patient who traveled in asia. 200818434554
alternative hand contamination technique to compare the activities of antimicrobial and nonantimicrobial soaps under different test conditions.antimicrobial hand soaps provide a greater bacterial reduction than nonantimicrobial soaps. however, the link between greater bacterial reduction and a reduction of disease has not been definitively demonstrated. confounding factors, such as compliance, soap volume, and wash time, may all influence the outcomes of studies. the aim of this work was to examine the effects of wash time and soap volume on the relative activities and the subsequent transfer of bacteria to inanimate objects for antimi ...200818441107
nonbloody, red stools from coadministration of cefdinir and iron-supplemented infant formulas.cefdinir is an extended-spectrum, third-generation cephalosporin that may be used for treatment of acute otitis media in patients allergic to penicillin. when administered with iron-containing products, including infant formulas, cefdinir or one of its metabolites may bind to ferric ions, forming a nonabsorbable complex that imparts a reddish color to the stool. we describe a 9-month-old infant with failure to thrive and acute otitis media who developed an erythematous maculopapular rash during ...200818447664
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
deoxycholate interacts with ipad of shigella flexneri in inducing the recruitment of ipab to the type iii secretion apparatus needle tip.type iii secretion (tts) is an essential virulence function for shigella flexneri that delivers effector proteins that are responsible for bacterial invasion of intestinal epithelial cells. the shigella tts apparatus (ttsa) consists of a basal body that spans the bacterial inner and outer membranes and a needle exposed at the pathogen surface. at the distal end of the needle is a "tip complex" composed of invasion plasmid antigen d (ipad). ipad not only regulates tts, but is required for the rec ...200818450744
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
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
what's the point of the type iii secretion system needle?recent work by several groups has significantly expanded our knowledge of the structure, regulation of assembly, and function of components of the extracellular portion of the type iii secretion system (t3ss) of gram-negative bacteria. this perspective presents a structure-informed analysis of functional data and discusses three nonmutually exclusive models of how a key aspect of t3ss biology, the sensing of host cells, may be performed.200818458349
global epidemiology of infections due to shigella, salmonella serotype typhi, and enterotoxigenic escherichia coli. 200818461719
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
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
simple sequence repeats in different genome sequences of shigella and comparison with high gc and at-rich genomes.simple sequence repeats (ssrs) are omnipresent in prokaryotes and eukaryotes, and are found anywhere in the genome in both protein encoding and noncoding regions. in present study the whole genome sequences of seven chromosomes (shigella flexneri 2a str301 and 2457t, shigella sonnei, escherichia coli k12, mycobacterium tuberculosis, mycobacterium leprae and staphylococcus saprophyticus) have downloaded from the genbank database for identifying abundance, distribution and composition of ssrs and ...200818464038
timeliness of enteric disease surveillance in 6 us states.we reviewed timeline information for a sample of salmonella spp., shigella spp., campylobacter spp., and escherichia coli o157:h7 cases and all confirmed foodborne outbreaks reported in 6 states during 2002. increasing the timeliness of case follow-up, molecular subtyping, and linkage of results are critical to reducing delays in the investigation of foodborne outbreaks.200818258128
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