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screening, purification, and identification of the enzyme producing n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester from l-isoasparagine and l-phenylalanine methyl ester.screening was carried out for microorganisms able to produce n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester [apm] from l-isoasparagine and l-phenylalanine methyl ester hydrochloride. of the 422 strains examined, 44 strains belonging to the family enterobacteriaceae were found to produce apm. the enzyme catalyzing apm production was purified and identified as dipeptidase e.200919664550
diarrhea in children less than two years of age with known hiv status in kisumu, kenya.to compare the frequency and etiology of diarrhea in children aged less than 2 years with known hiv status.201019664950
study on induction of apoptosis on hela and vero cells by recombinant shiga toxin and its subunits.verotoxin (vt) or shiga toxin (stx) produced by enterohemorrhagic escherichia coli (ehec) and shigella dysenteriae is ab5 holotoxin with potent protein synthesis inhibitor. vt can induce both apoptosis and necrosis depending on the cell type, it has been shown that vt-induced apoptosis and cytotoxicity are distinct processes, and the a subunit can be necessary for apoptosis. in other words, the precise role of each subunit in apoptosis signaling has yet to be established. in this study, inductio ...200919669659
vaccination of children in low-resource countries against shigella is unlikely to present an undue risk of reactive arthritis.shigellosis is a major cause of morbidity and mortality among children in low-resource countries. promising vaccine strategies in development include genetically attenuated shigella, killed whole cell vaccines, subcellular vaccines, and o-polysaccharide-protein conjugates. there is a concern that shigella vaccines could either induce reactive arthritis or could prime vaccinees for arthritis after a subsequent exposure to the pathogen because shigellosis is associated with reactive arthritis, esp ...200919643213
shigella phagocytic vacuolar membrane remnants participate in the cellular response to pathogen invasion and are regulated by autophagy.intracellular pathogens like shigella flexneri enter host cells by phagocytosis. once inside, the pathogen breaks the vacuolar membrane for cytosolic access. the fate and function of the vacuolar membrane remnants are not clear. examining shigella-infected nonmyeloid cells, we observed that proteins associated with vacuolar membrane remnants are polyubiquinated, recruit the autophagy marker lc3 and adaptor p62, and are targeted to autophagic degradation. further, inflammasome components and casp ...200919683680
a genome-scale proteomic screen identifies a role for dnak in chaperoning of polar autotransporters in shigella.autotransporters are outer membrane proteins that are widely distributed among gram-negative bacteria. like other autotransporters, the shigella autotransporter icsa, which is required for actin assembly during infection, is secreted at the bacterial pole. in the bacterial cytoplasm, icsa localizes to poles and potential cell division sites independent of the cell division protein ftsz. to identify bacterial proteins involved in the targeting of icsa to the pole in the bacterial cytoplasm, we sc ...200919684128
protective role of mouse mbl-c on intestinal mucosa during shigella flexneri invasion.mannan-binding lectin (mbl) is a c-type serum lectin, which is believed to play an important role in the innate immunity against a variety of pathogens. mbl can bind to sugar determinants of a wide variety of microorganisms, neutralize them and inhibit infection by complement activation through the lectin pathway and opsonization by collectin receptors. given that small intestine is a predominant site of extrahepatic expression of mbl, here we addressed the question whether mbl is involved in mu ...200919684159
differential expression of enteric neuroimmune-network in invasive and acute watery diarrhoea.we aimed to evaluate the changes of nerve morphology and distribution of neurotransmitters and neuropeptides in the rectum of shigella flexneri-infected patients and in the duodenum of vibrio cholerae o1-infected patients. nerve morphology was observed by transmission electron microscopy. immunoreactivity of nerve growth factor (ngf), neurotransmitters and neuropeptides in tissues were studied by immunohistochemistry. ultrastructural analysis of intestinal biopsy revealed persisting axons degene ...201019650770
clinical practice. today's understanding of the haemolytic uraemic syndrome.the haemolytic uraemic syndrome (hus) includes the triad of haemolytic anaemia, thrombocytopenia, and acute renal failure. the classical form [d(+) hus] is caused by infectious agents, and it is a common cause of acute renal failure in children. the enterohaemorrhagic escherichia coli-producing shiga toxin (stx) is the most common infectious agent causing hus. other infectious agents are shigella and streptococcus pneumoniae. infections by s. pneumoniae can be particularly severe and has a highe ...201019707787
purification and characterization of an immunogenic outer membrane protein of shigella flexneri 2a.in the present study we purified 34 kda major outer membrane protein (momp) of shigella flexneri 2a for the first time, which was cross-reactive and antigenically conserved among shigella spp. and the epitope was surface exposed on the intact bacterium. the purified antigen was found to be glycosylated, which aids in binding to macrophages and up-regulated the production of nitric oxide, granulocyte-colony stimulating factor and il-12p70, indicating that the momp is immunogenic and has the abili ...200919660587
review article: anti-inflammatory mechanisms of action of saccharomyces boulardii.saccharomyces boulardii, a well-studied probiotic, can be effective in inflammatory gastrointestinal diseases with diverse pathophysiology, such as inflammatory bowel disease (ibd), and bacterially mediated or enterotoxin-mediated diarrhoea and inflammation.200919706150
increasing resistance to nalidixic acid in shigella subgroups in a comparative study between 2001-2003 and 2004-2006.the shigella spp. is an organism with an ongoing changing resistance pattern to different antibiotics, thus making its appropriate treatment difficult. nalidixic acid has been one of the most common agents used for the treatment of shigellosis. recently, some studies have reported an emerging resistance to this agent.200919710978
when shigella tells the cell to hang on.ospe, a shigella type iii effector binds to integrin-like kinase and enhances cell adhesion to better disseminate and colonize the intestinal epithelium. because of the existence of ospe orthologues in other enteropathogens such as enteropathogenic escherichia coli or salmonella sp., maintenance of cell adhesion appears as a widespread strategy for bacteria that interact with the intestinal epithelium.200919720630
assessment of cell surface properties and adhesion potential of selected probiotic strains.to evaluate the physicochemical cell surface and adhesive properties of selected probiotic strains for human use.200919725886
comparison of the entericbio multiplex pcr system with routine culture for detection of bacterial enteric pathogens.the entericbio system uses a multiplex pcr assay for the simultaneous detection of campylobacter spp., salmonella enterica, shigella spp., and escherichia coli o157 from feces. it combines overnight broth enrichment with pcr amplification and detection by hybridization. an evaluation of this system was conducted by comparing the results obtained with the system with those obtained by routine culture, supplemented with alternative pcr detection methods. in a study of 773 samples, routine culture ...200919726596
structure of the heme/hemoglobin outer membrane receptor shua from shigella dysenteriae: heme binding by an induced fit mechanism.shigella dysentriae and other gram-negative human pathogens are able to use iron from heme bound to hemoglobin for growing. we solved at 2.6 a resolution the 3d structure of the tonb-dependent heme/hemoglobin outer membrane receptor shua from s. dysenteriae. shua binds to hemoglobin and transports heme across the outer membrane. the structure consists of a c-terminal domain that folds into a 22-stranded transmembrane beta-barrel, which is filled by the n-terminal plug domain. one distal histidin ...201019731368
oxidative and antibacterial activity of mn3o4.mn(3)o(4) nanoparticles with diameter ca. 10nm were synthesized by the forced hydrolysis of mn(ii) acetate at 80 degrees c. the x-ray diffraction (xrd), fourier transform infra red (ft-ir) spectroscopy, scanning electron microscopy (sem) and energy dispersive x-ray (edx) techniques were employed to study structural features and chemical composition of the nanoparticles. the unique oxidative activity of the mn(3)o(4) nanoparticles was demonstrated in the polymerization and dye degradation reactio ...200919733434
the escherichia coli o149 rfb gene cluster and its use for the detection of porcine e. coli o149 by real-time pcr.pcr or hybridization assays are widely used for the identification and detection of various escherichia coli serogroups and serotypes. this study explored this approach for the detection of e. coli o149 in pigs, a dominant serogroup among those associated with porcine post-weaning diarrhea (pwd) worldwide. for this purpose, we sequenced the o antigen (rfb) gene cluster of a representative enterotoxigenic e. coli (etec) o149:h10 strain and identified a 2kbp region specific for the o149 rfb gene c ...201019733452
evaluation of isolation methods for pathogenic yersinia enterocolitica from pig intestinal content.the aim of this study was to evaluate the efficiency of four isolation methods for the detection of pathogenic yersinia enterocolitica from pig intestinal content.201019735331
magnitude of drug resistant shigellosis: a report from bangalore.shigella is an important cause of acute invasive diarrhea in children and others. antimicrobial susceptibility of shigella spp. isolated from diarrhoeal/ dysenteric patients in bangalore was studied in our hospital from january 2002 to december 2007. one hundred and thirty-four isolates were identified as shigella species. s. flexneri, s. sonnei , s. boydii and s. dysenteriae were accounted respectively for 64.9%, 21.6%, 8.2% and 3.7% of the total number of shigella isolated. of these 56 (41.8%) ...200919736408
transmission risk factors and treatment of pediatric shigellosis during a large daycare center-associated outbreak of multidrug resistant shigella sonnei: implications for the management of shigellosis outbreaks among children.shigellosis outbreaks in daycare centers result in substantial disease and economic burdens in the united states. the emergence of multidrug resistant shigella strains raises questions regarding control of transmission within daycare centers and treatment for children. from may to october 2005, 639 shigella sonnei cases were reported in northwest missouri, mostly among persons exposed to daycare centers.200919738503
bacterial jailbreak sounds cellular alarm: phagosome membrane remnants trigger signaling.shigella flexneri and other invasive bacteria rupture the phagosome membrane and escape to the host cytoplasm. now, dupont et al. address the fate and signaling functions of pathogen vacuole remnants and show that these membrane fragments trigger host-cell-signaling responses, including polyubiquitination, autophagy, and pyroptosis.200919683675
analysis of a temporal cluster of shigella boydii isolates in mpumalanga, south africa, november to december 2007.shigellosis is a global human health problem. the disease is most prevalent in developing countries with poor access to safe potable water and sanitation. shigella boydii is of particular epidemiological importance in developing nations such as african and asian countries. in the present study, we report on the analysis of a temporal cluster of 29 s. boydii serotype 2 strains, isolated in the mpumalanga province of south africa (sa) over the period of november to december 2007.200919749451
bcl-2 regulates the onset of shiga toxin 1-induced apoptosis in thp-1 cells.shiga toxins (stxs), which are proteins expressed by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli, are potent protein synthesis inhibitors. stx-producing organisms cause bloody diarrhea with the potential to progress to acute renal failure and central nervous system complications. studies using animal models of these diseases have shown that stxs are major virulence factors, and purified toxins have been shown to be capable of killing many types of ...200919752028
multiplexed bead-based mesofluidic system for detection of food-borne pathogenic bacteria.in the present study, a simple and rapid multiplexed bead-based mesofluidic system (bms) was developed for simultaneous detection of food-borne pathogenic bacteria, including staphylococcus aureus, vibrio parahaemolyticus, listeria monocytogenes, salmonella, enterobacter sakazakii, shigella, escherichia coli o157:h7, and campylobacter jejuni. this system is based on utilization of isothiocyanate-modified microbeads that are 250 mum in diameter, which were immobilized with specific amino-modified ...200919717622
molecular characterization of esbl-producing shigella sonnei isolates from patients with bacilliary dysentery in lebanon.emergence of extended-spectrum beta-lactamases (esbls) in shigella species imparting resistance to third-generation cephalosporins is a growing concern worldwide. the aim of this study is to molecularly characterize the newly emerging beta-lactam resistant shigella sonnei, specifically esbls in lebanon, and compare them to beta-lactam sensitive isolates.200919759494
effect of iron on cytolysin a expression in salmonella enterica serovar typhi.previously, a novel protein clya (cytolysin a) has been identified in escherichia coli k-12, salmonella enterica serovars typhi and paratyphi a and shigella. salmonella spp. synthesize substantial amounts of clya upon infection of the human host, although the mechanism by which clya is induced in vivo is unclear. since environmental signals could control the expression of virulence determinants, clya expression in s. typhi ty2 was tested by western blotting in the presence of normal pooled human ...200919763423
a new multiplex pcr for differential identification of shigella flexneri and shigella sonnei and detection of shigella virulence determinants.most of the multiplex pcr (mpcr) used to identify shigella do not discriminate between shigella species or serotypes. we designed a mpcr to differentiate between s. flexneri and s. sonnei strains based on the detection of markers associated with the she pathogenicity island described in shigella. in addition, specific primers were included to detect the shigella virulence determinants shet-1 and shet-2 enterotoxin genes. the analysis of 304 shigella strains from chile and 79 shigella strains fro ...201019765332
high-affinity inhibitors of trna-guanine transglycosylase replacing the function of a structural water cluster.the trna-modifying enzyme trna-guanine transglycosylase (tgt) is essential for the pathogenic mechanism of shigella flexneri, the causing agent of the bacterial diarrheal disease shigellosis. herein, the synthesis of a new class of rationally designed 6-amino-imidazo[4,5-g]quinazolin-8(7h)-one- (lin-benzoguanine) based inhibitors of tgt are reported. in order to accommodate a small hydrophobic crevice opening near the binding site of ribose-34, 2-aminoethyl substituents were introduced in positi ...200919746363
a novel glucosyltransferase involved in o-antigen modification of shigella flexneri serotype 1c.the o antigen of serotype 1c differs from the unmodified o antigen of serotype y by the addition of a disaccharide (two glucosyl groups) to the tetrasaccharide repeating unit. it was shown here that addition of the first glucosyl group is mediated by the previously characterized gtri cluster, which is found within a cryptic prophage at the proa locus in the bacterial chromosome. transposon mutagenesis was performed to disrupt the gene responsible for addition of the second glucosyl group, causin ...200919717593
microwave assisted, one-pot synthesis of 5-nitro- 2-aryl substituted-1h-benzimidazole libraries: screening in vitro for antimicrobial activity.the efficient and rapid synthesis of 5-nitro-2-aryl substituted-1h-benzimidazole libraries (1a-1j) has been established. thus, both microwave and conventional cyclo-condensation of 4-nitro ortho-phenylenediamine with various phenoxyacetic acids were carried out in the presence of hcl catalyst. the microwave synthesis route afforded advantages, such as good to excellent yields, shorter reaction time (2.5-3.5 min), readily available starting material, and simple purification procedure, which disti ...200919772484
peptide sequences identified by phage display are immunodominant functional motifs of pet and pic serine proteases secreted by escherichia coli and shigella flexneri.plasmid-encoded toxin (pet) and protein involved in colonization (pic), are serine protease autotransporters of enterobacteriaceae (spates) secreted by enteroaggregative escherichia coli (eaec), which display the gdsgsg sequence or the serine motif. our research was directed to localize functional sites in both proteins using the phage display method. from a 12mer linear and a 7mer cysteine-constrained (c7c) libraries displayed on the m13 phage piii protein we selected different mimotopes using ...200919772881
isolation of salmonella and shigella from fish harvested from the winam gulf of lake victoria, kenya.human infections caused by pathogens transmitted from fish are quite common. the aim of this study was to isolate enteric pathogenic bacteria from fish that might be transmitted to humans after the handling or consumption of such fish.200919755738
safety and colonization of two novel virg(icsa)-based live shigella sonnei vaccine strains in rhesus macaques (macaca mulatta).shigella are gram-negative bacterium that cause bacillary dysentery (shigellosis). symptoms include diarrhea and discharge of bloody mucoid stools, accompanied by severe abdominal pain, nausea, vomiting, malaise, and fever. persons traveling to regions with poor sanitation and crowded conditions become particularly susceptible to shigellosis. currently a vaccine for shigella has not been licensed in the united states, and the organism quickly becomes resistant to medications. during the past 10 ...200819793462
the pathogenic properties of a novel and conserved gene product, kerv, in proteobacteria.identification of novel virulence factors is essential for understanding bacterial pathogenesis and designing antibacterial strategies. in this study, we uncover such a factor, termed kerv, in proteobacteria. experiments carried out in a variety of eukaryotic host infection models revealed that the virulence of a pseudomonas aeruginosa kerv null mutant was compromised when it interacted with amoebae, plants, flies, and mice. bioinformatics analyses indicated that kerv is a hypothetical methyltra ...200919779606
genome sequences of escherichia coli b strains rel606 and bl21(de3).escherichia coli k-12 and b have been the subjects of classical experiments from which much of our understanding of molecular genetics has emerged. we present here complete genome sequences of two e. coli b strains, rel606, used in a long-term evolution experiment, and bl21(de3), widely used to express recombinant proteins. the two genomes differ in length by 72,304 bp and have 426 single base pair differences, a seemingly large difference for laboratory strains having a common ancestor within t ...200919786035
immunomodulation using genetically engineered bacteria for type iii-mediated delivery of heterologous antigens and cytokines: potential application in vaccine and therapeutical developments.the rational design of new approaches aiming to improve antigen or drug delivery remains a major challenge in numerous vaccine and therapeutical strategies. studies on genetically engineered bacteria have led to significant progress in the delivery of heterologous proteins. yet, the efficiency of such recombinant bacteria relies particularly on their ability to deliver sufficient amount of the drug to intended cell tissues. gram-negative bacteria like salmonella, shigella, yersinia and pseudomon ...201019778176
uropathogenic escherichia coli suppresses the host inflammatory response via pathogenicity island genes sisa and sisb.extraintestinal pathogenic escherichia coli can successfully colonize the urinary tract of the immunocompetent host. in part, this is accomplished by dampening the host immune response. indeed, the sisa and sisb genes (shia-like inflammation suppressor genes a and b) of uropathogenic e. coli strain cft073, homologs of the shigella flexneri shi-2 pathogenicity island gene shia, suppress the host inflammatory response. a double deletion mutant (deltasisa deltasisb) resulted in a hyperinflammatory ...200919797063
effects of enteropathogenic bacteria & lactobacilli on chemokine secretion & toll like receptor gene expression in two human colonic epithelial cell lines.the intestinal epithelium is part of the innate immune system responding to contact with pathogenic or commensal bacteria. the objective of this study was to compare innate responses of intestinal epithelial cell lines to pathogenic bacteria and to lactobacilli.200919797815
overseas outbreaks of infectious intestinal disease identified in scotland, 2003 to 2007.this article presents information on all potential outbreaks of infectious intestinal disease (iid) identified by health protection scotland (hps) involving residents of scotland. unlike other systems, this alert system covers potential outbreaks of iid rather than apparently sporadic cases and covers all gastrointestinal pathogens, all visited countries, and all groups of travelers.200919796102
proteome analysis of an attenuated francisella tularensis dsba mutant: identification of potential dsba substrate proteins.francisella tularensis (f. tularensis) is highly infectious for humans via aerosol route and untreated infections with the highly virulent subsp. tularensis can be fatal. our knowledge regarding key virulence determinants has increased recently but is still somewhat limited. surface proteins are potential virulence factors and therapeutic targets, and in this study, we decided to target three genes encoding putative membrane lipoproteins in f. tularensis lvs. one of the genes encoded a protein w ...200919799467
antibiotic resistance among shigella serogroups isolated in tehran, iran (2002-2004). 200919801811
autophagy in immunity against intracellular bacteria.autophagy is an innate immune defense mechanism against various intracellular bacterial pathogens, such as salmonella enterica serovar typhimurium (s. typhimurium), listeria monocytogenes and shigella flexneri. s. typhimurium uses type three secretion systems (t3sss) to invade mammalian cells and replicate in salmonella-containing vacuoles (scvs). a small population of intracellular s. typhimurium is targeted by autophagy shortly after infection. evidence suggests that these bacteria are present ...200919802566
spa15 of shigella flexneri is secreted through the type iii secretion system and prevents staurosporine-induced apoptosis.shigella flexneri is a gram-negative, facultative intracellular pathogen that invades the colonic epithelium and causes bacillary dysentery. we previously demonstrated that s. flexneri inhibits staurosporine-induced apoptosis in infected epithelial cells and that a deltamxie mutant is unable to inhibit apoptosis. therefore, we hypothesized that an mxie-regulated gene was responsible for protection of epithelial cells from apoptosis. analysis of all mxie-regulated genes yielded no mutants that la ...200919805534
in-vitro activity of ceftazidime, a beta-lactamase stable cephalosporin.the in-vitro activity and beta-lactamase stability of ceftazidime were evaluated against 700 gram-positive and gram-negative bacteria. ceftazidime was less active than penicillins or older cephalosporins against staphylococcus spp. and streptococcus spp., and it did not inhibit streptococcusfaecalis. however, ceftazidime was as active as moxalactam and cefoperazone against escherichia coli, klebsiella and proteus mirabilis with mics less than 0.2 mg/l. ceftazidime also inhibited enterobacter, ci ...198119810175
automated use of whonet and satscan to detect outbreaks of shigella spp. using antimicrobial resistance phenotypes.antimicrobial resistance is a priority emerging public health threat, and the ability to detect promptly outbreaks caused by resistant pathogens is critical for resistance containment and disease control efforts. we describe and evaluate the use of an electronic laboratory data system (whonet) and a space-time permutation scan statistic for semi-automated disease outbreak detection. in collaboration with whonet-argentina, the national network for surveillance of antimicrobial resistance, we appl ...201019796449
the shigella dysenteriae serotype 1 proteome, profiled in the host intestinal environment, reveals major metabolic modifications and increased expression of invasive proteins.shigella dysenteriae serotype 1 (sd1) causes the most severe form of epidemic bacillary dysentery. we present the first comprehensive proteome analysis of this pathogen, profiling proteins from bacteria cultured in vitro and bacterial isolates from the large bowel of infected gnotobiotic piglets (in vivo). overall, 1061 distinct gene products were identified. differential display analysis revealed that sd1 cells switched to an anaerobic energy metabolism in vivo. high in vivo abundances of amino ...200919813213
comparative genomics reveal the mechanism of the parallel evolution of o157 and non-o157 enterohemorrhagic escherichia coli.among the various pathogenic escherichia coli strains, enterohemorrhagic e. coli (ehec) is the most devastating. although serotype o157:h7 strains are the most prevalent, strains of different serotypes also possess similar pathogenic potential. here, we present the results of a genomic comparison between ehecs of serotype o157, o26, o111, and o103, as well as 21 other, fully sequenced e. coli/shigella strains. all ehecs have much larger genomes (5.5-5.9 mb) than the other strains and contain sur ...200919815525
antibiotic therapy for shigella dysentery.shigella dysentery is a relatively common illness and occasionally causes death, worldwide. mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. the antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects.200919821387
prevalence of staphylococcus aureus and intestinal parasites among food handlers in sanliurfa, southeastern anatolia.food-borne diseases represent a persistent global health burden, and food handlers play a major role in their transmission. staphylococcus aureus carriage and intestinal parasitism are important risk factors for the contamination of food and water. this study was undertaken to determine the prevalence of staphylococcus aureus and intestinal parasites among food handlers working in sanliurfa, southeastern anatolia.200919823157
computational study of the conformational structures of saccharides in solution based on j couplings and the "fast sugar structure prediction software".this article reports on the implementation of j coupling calculations in our recently developed fast sugar structure prediction software (fsps). the fsps combines a smart and exhaustive algorithm to search through conformational space with the calculation of different experimental nuclear magnetic resonance observables to establish the conformation of saccharides in solution. using our algorithm in combination with nmr data, we investigate the solution structure of three simple disaccharides (me ...200919795837
beneficial role of green plantain [musa paradisiaca] in the management of persistent diarrhea: a prospective randomized trial.to evaluate the beneficial effects of green plantain-based diet on stool volume, frequency and weight gain as compared with a traditional yogurt-based diet in children with persistent diarrhea.200919828902
how autophagy regulates the host cell signaling associated with the postpartum bacteria cocoon experienced as a danger signal.shigella, the causative agent of human bacillary dysentery, invades the host cell, rapidly breaking the phagosome and multiplying in the cytosol. here, we summarize our recent work showing the targeting of the leftover membrane remnants to autophagy together with trapped membrane-associated signaling molecules recruited during the immediate early entry step. we suggest that this mechanism participates in the bacteria-dependent orchestration of the cell response. moreover, we propose that this si ...200919829050
effect of x-ray treatments on inoculated escherichia coli o157: h7, salmonella enterica, shigella flexneri and vibrio parahaemolyticus in ready-to-eat shrimp.this study was conducted to evaluate the inactivation effect of x-ray treatments on escherichia coli o157: h7, salmonella enteric (s. enterica), shigella flexneri (s. flexneri) and vibrio parahaemolyticus (v. parahaemolyticus) artificially inoculated in ready-to-eat (rte) shrimp. a mixed culture of three strains of each tested pathogen was used to inoculate rte shrimp. the shrimp samples were inoculated individually with selected pathogenic bacteria then aseptically placed in sterile plastic cup ...200919835772
shigella infection of intestinal epithelium and circumvention of the host innate defense system.shigella, gram-negative bacteria closely related to escherichia coli, are highly adapted human pathogens that cause bacillary dysentery. although shigella have neither adherence factors nor flagella required for attaching or accessing the intestinal epithelium, shigella are capable of colonizing the intestinal epithelium by exploiting epithelial-cell functions and circumventing the host innate immune response. during shigella infection, they deliver many numbers of effectors through the type iii ...200919812985
requirement for formin-induced actin polymerization during spread of shigella flexneri.actin polymerization in the cytosol and at the plasma membrane is locally regulated by actin nucleators. several microbial pathogens exploit cellular actin polymerization to spread through tissue. the movement of the enteric pathogen shigella flexneri, both within the cell body and from cell to cell, depends on actin polymerization. during intercellular spread, actin polymerization at the bacterial surface generates protrusions of the plasma membrane, which are engulfed by adjacent cells. in the ...201019841078
genetic diversity of o157:h7 and non-o157 verocytotoxigenic escherichia coli from argentina inferred from multiple-locus variable-number tandem repeat analysis (mlva).although serotype o157:h7 has been implicated in most cases of haemolytic-uraemic syndrome (hus), there is growing concern about non-o157 serotypes of verocytotoxigenic escherichia coli (vtec). multiple-locus variable-number tandem repeat analysis (mlva) has been focused on the specific typing of o157:h7 isolates, but recently, a generic mlva assay for e. coli and shigella has been developed. we performed a study of the polymorphism in 7 generic vntr loci both in vtec o157:h7 and non-o157 isolat ...201019850517
pretreatment of epithelial cells with rifaximin alters bacterial attachment and internalization profiles.rifaximin is a poorly absorbed semisynthetic antibiotic derivative of rifampin licensed for use in the treatment of traveler's diarrhea. rifaximin reduces the symptoms of enteric infection, often without pathogen eradication and with limited effects on intestinal flora. epithelial cells (hep-2 [laryngeal], hct-8 [ileocecal], a549 [lung], and hela [cervical]) were pretreated with rifaximin (or control antibiotics) prior to the addition of enteroaggregative escherichia coli (eaec). eaec adherence ...201019858255
epidemiology of shigella-associated diarrhea in gorgan, north of iran.shigella is an important etiological agent for diarrhea and especially dysentery. shigellosis is an intestinal infection that is a major public health problem in many developing countries. the aim of this study was to evaluate the prevalence of shigella and its various species in diarrheal samples in gorgan located in the north of iran.200719858629
escherichia coli as reservoir for macrolide resistance genes.the plasmid-borne mph(a) gene that confers resistance to azithromycin and has recently emerged in shigella sonnei is present in multidrug- and non-multidrug-resistant escherichia coli isolates from 4 continents. further spread of mph(a) to shigella and salmonella spp. may be expected.200919861064
salmonella carriers among expatriate workers in al-qatif area.salmonella infection and diarrhoeal diseases are major causes of morbidity and mortality in the developing world. all expatriates applying for work permits in the kingdom of saudi arabia (ksa) have to undergo a governmental compulsory health check program.200419861837
secretory iga-mediated neutralization of shigella flexneri prevents intestinal tissue destruction by down-regulating inflammatory circuits.shigella, a gram-negative invasive enteropathogenic bacterium responsible for bacillary dysentery, causes the rupture, invasion, and inflammatory destruction of the human colonic mucosa. we explored the mechanisms of protection mediated by shigella lps-specific secretory iga (siga), the major mucosal ab induced upon natural infection. bacteria, siga, or siga-s. flexneri immune complexes were administered into rabbit ligated intestinal loops containing a peyer's patch. after 8 h, localizations of ...200919828639
[dysentery and amoebiasis in poland in 2007].the number as well as incidence rate of notified as shigellosis, bacillary dysentery cases in xxi century are low. only 64 cases were notified in the year 2007 (incidence rate 0.17/100,000 population), while 35 (incidence rate 0.09) were notified in 2006 and median in the 2001-2005 years was 80, incidence rate 0.21/100,000 population. since 2000 no one-death case was notified. seven imported cases were notified as they got infection being abroad, in egypt 6: 4 cases got s. flexneri, two s. sonne ...200919799247
nutritional cytopenia in monkeys receiving the goldberger diet.experiments are reported upon young rhesus monkeys which were given a diet essentially the same as the goldberger black tongue-producing diet, supplemented in various ways. those receiving the unsupplemented diet developed the syndrome characterized by leucopenia, anemia, gingivitis, diarrhea, and death, which has been previously described in monkeys receiving our diet of refined foodstuffs. an animal receiving the goldberger diet supplemented with ascorbic acid and liver extract exhibited norma ...194019871037
studies on the flexner group of dysentery bacilli : ii. the chemical degradation of the specific antigen of type z shigella paradysenteriae (flexner).the chemical and enzymatic dissociation of the specific antigen of type z shigella paradysenteriae has been studied. the chemical, toxic, and serological properties of the products of degradation have been investigated. the nature of the toxic component has been discussed.194519871461
studies on the flexner group of dysentery bacilli : iii. antibody response in man following the administration of the specific antigen of type v shigella paradysenteriae (flexner).1. volunteers have been immunized with the purified specific antigen of type v shigella paradysenteriae (flexner). the subjects developed a high titer of bacterial agglutinins and mouse-protective antibodies. the agglutinin titer fell moderately after a period of 6 months. the subjects responded fairly well to a small recall dose of the antigen. 2. two individuals from a group of 10 injected with the specific polysaccharide obtained from type v organisms responded with an increase in bacterial a ...194519871462
mechanism of the augmenting action of mineral oil on antibody production : tissue reactions and antibody response to dysentery vaccine in saline, and in saline-lanolin-mineral oil emulsion.a comparative study was made in rabbits of antibody production and tissue changes following the injection into the foot pads, of saline in falba and mineral oil emulsion, of killed cells of shigella paradysenteriae flexner in saline, and of killed cells of shigella paradysenteriae in saline in falba-mineral oil emulsion. it was found that antibody production was greatly prolonged by the emulsification in oil. while with antigen in saline the serum titers began to fall 9 days after injection and ...194519871505
studies on the nature of resistance of gram-negative bacilli to penicillin : antagonistic and enhancing effects of amino acids.the susceptibility of e. coli and salmonella to penicillin is highest in a basal medium devoid of amino acids. blood serum in certain concentrations, meat infusion broth, yeast extract, and casein hydrolysate interfere with the penicillin activity. the effect is apparently due to the antagonism of certain amino acids in the materials. dicarboxyl-monoamino acids (i.e. aspartic, glutamic, and hydroxyglutamic acids and asparagine) cystine, arginine, histidine, and hydroxyproline are capable of supp ...194619871516
preparation and properties of shiga toxin and toxoid.1. shigella dysenteriae (shiga) can, under the proper cultural conditions, produce a soluble toxin which is independent of the specific somatic polysaccharide antigen. a method is described for the rapid production of this toxin by an avirulent r variant of this organism. 2. the amount of bacterial protoplasm synthesized, and the yield of toxin produced, are very much increased when the culture is grown under conditions which favor aerobic metabolism and which do not permit accumulation of organ ...194619871559
studies on the flexner group of dysentery bacilli : v. a quantitative study of the serological cross-reactions.a quantitative study of the serological cross-reactions of the somatic antigens of types i, iii, and i-iii shigella paradysenteriae has been made. from the results obtained it has been concluded that the somatic antigens of shigella paradysenteriae (flexner) types i, iii, and i-iii are single chemical substances. the specificity and serological cross-reactions exhibited by these antigens are dependent upon similarities in their chemical constitutions.194619871567
studies on the flexner group of dysentery bacilli : vi. the detoxification of shigella paradysenteriae by means of periodic acid.a method for detoxifying type z and sp. newcastle sh. paradysenteriae (flexner) has been described. this procedure involves exposing the bacilli at ph 5.0 to 0.01 m periodic acid. microorganisms treated with this reagent for an appropriate time interval lose approximately 90 per cent of their toxicity, yet they are capable of eliciting in experimental animals antibodies effective against the unaltered organisms.194719871632
evaluation of new chromogenic substrates for the detection of coliforms.to evaluate a new range of chromogenic substrates for the detection of beta-galactosidase activity in coliforms and to compare their performance in agar media and broths.201019878523
virulence, inflammatory potential, and adaptive immunity induced by shigella flexneri msbb mutants.the ability of genetically detoxified lipopolysaccharide (lps) to stimulate adaptive immune responses is an ongoing area of investigation with significant consequences for the development of safe and effective bacterial vaccines and adjuvants. one approach to genetic detoxification is the deletion of genes whose products modify lps. the msbb1 and msbb2 genes, which encode late acyltransferases, were deleted in the shigella flexneri 2a human challenge strain 2457t to evaluate the virulence, infla ...201019884336
the multiplication of bacteriophage in vivo and its protective effect against an experimental infection with shigella dysenteriae.1. anti-shiga bacteriophage injected into the general circulation can multiply in the brain of mice infected intracerebrally with shigella dysenteriae. 2. under proper conditions, the injection of active bacteriophage into the general circulation can protect mice against an otherwise fatal intracerebral infection with shigella dysenteriae. 3. the protection so induced appears to depend upon the early establishment of a high bacteriophage level in the infected animal.194319871319
pneumonia caused by shigella sonnei in man returned from india. 200919891897
the australian bush fly (musca vetustissima) as a potential vector in the transmission of foodborne pathogens at outdoor eateries.abstract australian outdoor activities are often accompanied by a barbeque (bbq) with family, friends, and guests, which are often interrupted by uninvited guests in the form of the australian bush fly, musca vetustissima. we investigated the bacterial loading associated with the australian bush in three different environments: on a cattle farm, in a typical urban area (shopping center car park), and at a bbq. the highest bacterial populations per fly were found to occur in a farm environment ( ...201019895260
caspase-8-mediated cleavage of bid and protein phosphatase 2a-mediated activation of bax are necessary for verotoxin-1-induced apoptosis in burkitt's lymphoma cells.verotoxin (vt-1) is a cytotoxin, produced by shigella dysenteriae type 1 or by shiga toxin-producing escherichia coli, which binds specifically to globotriaosylceramide (gb3). this glycosphingolipid is a b cell differentiation antigen (gb3/cd77) strongly expressed on burkitt's lymphoma cells. we have previously shown that, in these cells, vt-1 induces apoptosis via a caspase- and mitochondria-dependent pathway. in this report, we provide new insights into this signal transduction pathway. first, ...201019895884
spatial distribution of diarrhoea and microbial quality of domestic water during an outbreak of diarrhoea in the tshikuwi community in venda, south africa.total microbial quality assessment and geographical information system were used for evaluating the quality of water and the spatial distribution of diarrhoea cases in tshikuwi, a rural community in south africa, during an outbreak of diarrhoea. the water-abstraction points included two groundwater storage tanks, namely tank 1 and tank 2 and the khandanama river. indicator microbial counts for total coliforms, faecal coliforms, enterococci, and heterotrophic bacteria exceeded the limit for no ri ...200919902801
studies on the flexner group of dysentery bacilli : i. the specific antigens of shigella paradysenteriae (flexner).1. methods for the isolation of the specific antigens of types v, w, z, and newcastle shigella paradysenteriae are given. 2. the physical, chemical, toxic, and immunological properties of these substances are described.194519871460
effects of x-ray radiation on escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri inoculated on shredded iceberg lettuce.the main goal of this investigation was to study the efficacy of x-ray doses (0.1, 0.2, 0.3, 0.5, 0.75, 1.0, 1.5 and 2.0 kgy) on inoculated escherichia coli o157: h7, listeria monocytogenes, salmonella enterica and shigella flexneri on shredded iceberg lettuce. the second goal was to study the effect of x-ray on the inherent microflora counts and visual color of shredded iceberg lettuce during storage at 4 degrees c for 30 days. treatment with 1.0 kgy x-ray significantly reduced the population o ...201019913700
yersinia enterocolitica in slaughter pig tonsils: enumeration and detection by enrichment versus direct plating culture.tonsil samples from 139 slaughter pigs were examined for the presence of pathogenic yersinia enterocolitica by enrichment procedures based on the standard method iso 10273:2003. in addition, samples were tested by direct plating method to evaluate its efficiency compared to the enrichment culture methods and to quantify the level of contamination in porcine tonsils. in total, 52 samples (37.4%) were positive for pathogenic y. enterocolitica, all belonging to bioserotype 4/o:3. fifty out of the 5 ...201019913707
the mannitol operon repressor mtlr belongs to a new class of transcription regulators in bacteria.many bacteria express phosphoenolpyruvate-dependent phosphotransferase systems (pts). the mannitol-specific pts catalyze the uptake and phosphorylation of d-mannitol. the uptake system comprises several genes encoded in the single operon. the expression of the mannitol operon is regulated by a proposed transcriptional factor, mannitol operon repressor (mtlr) that was first studied in escherichia coli. here we report the first crystal structures of mtlr from vibrio parahemeolyticus (vp-mtlr) and ...200919840941
enteroinvasive escherichia coli vs. shigella flexneri: how different patterns of gene expression affect virulence.important features of the enteroinvasive escherichia coli (eiec) phenotype and gene expression likely to confer eiec with a lower ability to cause disease than shigella flexneri were described here for the first time. to confirm the lower pathogenicity of eiec, we have analyzed the keratoconjunctivitis developed in guinea-pigs with eiec or s. flexneri. shigella flexneri induced a more pronounced proinflammatory response, whereas eiec induced a mild form of the disease. eiec showed a significantl ...200919889166
in this issue.shigellosis, dysentery - by whatever name - don't kiss the chimps: pp. 5029-5045with a 10-15% mortality rate when untreated in young children and immunedeficient patients, over one million deaths per year are attributable to this primate/human-only disease. furthermore, the shigella spp. have developed resistance to b-lactam, tetracycline, and aminoglycoside antibiotics very rapidly. a non-primate model of the disease is based on gnotobiotic piglets. aerobically grown bacteria shift to anaerobic ...200919921678
inactivation of escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri on spinach leaves by x-ray.several recent foodborne disease outbreaks associated with leafy green vegetables, including spinach, have been reported. x-ray is a non-thermal technology that has shown promise for reducing pathogenic and spoilage bacteria on spinach leaves. inactivation of inoculated escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri on spinach leaves using x-ray at different doses (0.1, 0.2, 0.3, 0.5, 0.75, 1.0, 1.5 and 2.0 kgy) was studied. the effect of x-ray on col ...201019913687
studies on the antidiarrhoeal activity of aegle marmelos unripe fruit: validating its traditional usage.aegle marmelos (l.) correa has been widely used in indigenous systems of indian medicine due to its various medicinal properties. however, despite its traditional usage as an anti-diarrhoeal there is limited information regarding its mode of action in infectious forms of diarrhoea. hence, we evaluated the hot aqueous extract (decoction) of dried unripe fruit pulp of a. marmelos for its antimicrobial activity and effect on various aspects of pathogenicity of infectious diarrhoea.200919930633
a unified approach to molecular epidemiology investigations: tools and patterns in california as a case study for endemic shigellosis.shigellosis causes diarrheal disease in humans from both developed and developing countries, and multi-drug resistance is an emerging problem. the objective of this study is to present a unified approach that can be used to characterize endemic and outbreak patterns of shigellosis using use a suite of epidemiologic and molecular techniques. the approach is applied to a california case study example of endemic shigellosis at the population level.200919930709
characterization of wrss2 and wrss3, new second-generation virg(icsa)-based shigella sonnei vaccine candidates with the potential for reduced reactogenicity.live, attenuated shigella vaccine candidates, such as shigella sonnei strain wrss1, shigella flexneri 2a strain sc602, and shigella dysenteriae 1 strain wrsd1, are attenuated principally by the loss of the virg(icsa) protein. these candidates have proven to be safe and immunogenic in volunteer trials and in one study, efficacious against shigellosis. one drawback of these candidate vaccines has been the reactogenic symptoms of fever and diarrhea experienced by the volunteers, that increased in a ...201019932216
development of a serogroup-specific dna microarray for identification of escherichia coli strains associated with bovine septicemia and diarrhea.escherichia coli strains belonging to serogroups o8, o9, o15, o26, o35, o78, o86, o101, o115 and o119 are commonly associated with septicemia or diarrhea in calves and pose a significant threat to the cattle industry worldwide. in this study, a microarray detection system targeting o-antigen-specific genes was developed for the identification of those serogroups. by testing against 186 e. coli and shigella o-serogroup reference strains, 36 e. coli clinical isolates, and 9 representative strains ...201019932572
adaptive immune responses during shigella dysenteriae type 1 infection: an in vitro stimulation with 57 kda major antigenic omp in the presence of anti-cd3 antibody.an effort was made to understand the role of the 57 kda major antigenic fraction of shigella outer membrane protein (omp) in the presence of t-cell antigen receptor in activation of adaptive immune responses of the cell mediated immune (cmi) restored patients. the expression of hla-dr/cd4 out of cd3(+) t-cells was significantly dominant over the hla-dr/cd8 and comparable to unstimulated cells of infected or healthy controls. cd4(+) t-cell activation together with hla-dr is associated with the ex ...201019915959
purification, characterization, and gene cloning of glucose-1-phosphatase from citrobacter braakii.citrobacter braakii produced an intracellular acid glucose phosphatase (agpc) which was purified 986 fold to homogeneity with the specific activity of 286 units/mg. agpc hydrolyzed a wide variety of phosphorylated compounds with high activity for glucose-1-phosphate and glucose-6-phosphate. the optimum ph and temperature for the enzyme activity was ph 5.0 and 45 degrees c, respectively. the km value for glucose-1-phosphate was 5.12 mm with a vmax 27.8 u mg(-1). its molecular weight was 46 kda by ...200919940380
solution nmr structures of proteins vpa0419 from vibrio parahaemolyticus and yiis from shigella flexneri provide structural coverage for protein domain family pfam 04175. 201019927321
antimicrobial lipids from the hemolymph of brachyuran crabs.the potential of marine crabs as a source of biologically active products is largely unexplored. in the present study, antimicrobial activity of the hemolymph (plasma) and hemocytes (plasma cells) of six brachyuran crabs was investigated against 16 pathogenic strains. among the 16 strains tested maximum zone of inhibition was recorded in the hemolymph of hyas araneus against shigella flexineri. interestingly staphylococcus aureus and salmonella typhi were susceptible to all the hemolymph and hem ...201019937399
differentiation and identification of shigella spp. and enteroinvasive escherichia coli in environmental waters by a molecular method and biochemical test.both shigella spp. and enteroinvasive escherichia coli (eiec) are important human pathogens that are responsible for the majority of cases of endemic bacillary dysentery. however, they are difficult to identify and differentiate by biochemical tests or molecular methods alone. in this study, we developed a procedure to detect shigella spp. and eiec from environmental water samples using membrane filtration followed by nutrient broth enrichment, isolation using selective culture plates, and ident ...201019917511
galectin-3, a marker for vacuole lysis by invasive pathogens.shigella bacteria invade macrophages and epithelial cells and following internalization lyse the phagosome and escape to the cytoplasm. galectin-3, an abundant protein in macrophages and epithelial cells, belongs to a family of beta-galactoside-binding proteins, the galectins, with many proposed functions in immune response, development, differentiation, cancer and infection. galectins are synthesized as cytosolic proteins and following non-classical secretion bind extracellular beta-galactoside ...201019951367
[development of taqman real-time pcr in detection of aeromonas hydrophila].to develop a taqman real-time pcr for the detection of aeromonas hydrophila.200919954074
[investigation of a norovirus outbreak through contaminated centralized water supply system].to investigate the etiology and source of an infectious diarrhea outbreak and control the epidemic.200919954078
emergence of resistance to third-generation cephalosporin in shigella--a case report.the emergence of ciprofloxacin resistance in shigella has shifted the attention to cephalosporins. the first occurrence of third generation cephalosporin-resistant shigella flexneri was from france. this article reports the first case of cephalosporin-resistant s. flexneri from india. a 12-month-old child was admitted for a 20-day episode of loose stools, non-fetid, with mucus and blood. the stool sample showed the presence of blood and mucus and s. flexneri which was resistant to ampicillin, na ...201019955258
emergence of a new multidrug-resistant serotype x variant in an epidemic clone of shigella flexneri.shigella spp. are the causative agent of shigellosis with shigella flexneri serotype 2a being the most prevalent in developing countries. epidemiological surveillance in china found that a new serotype of s. flexneri appeared in 2001 and replaced serotype 2a in 2003 as the most prevalent serotype in henan province. the new serotype also became the dominant serotype in 7 of the 10 other provinces under surveillance in china by 2007. the serotype was identified as a variant of serotype x. it diffe ...201019955273
inactivated and subunit vaccines to prevent shigellosis.shigellosis remains a formidable disease globally, with children of the developing world bearing the greatest number of infections. the need for an affordable, safe and efficacious vaccine has persisted for decades. vaccines to prevent shigellosis can be divided into living and nonliving approaches. several nonliving shigella vaccines are currently at different stages of development and show substantial promise. outlined here is an overview of multiple nonliving vaccine technologies, highlightin ...200919943764
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