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a repulsive electrostatic mechanism for protein export through the type iii secretion apparatus.many gram-negative bacteria initiate infections by injecting effector proteins into host cells through the type iii secretion apparatus, which is comprised of a basal body, a needle, and a tip. the needle channel is formed by the assembly of a single needle protein. to explore the export mechanisms of mxih needle protein through the needle of shigella flexneri, an essential step during needle assembly, we have performed steered molecular dynamics simulations in implicit solvent. the trajectories ...201020141759
characterisation of multidrug-resistant salmonella typhimurium 4,[5],12:i:- dt193 strains carrying a novel genomic island adjacent to the thrw trna locus.in 2006, monophasic, multidrug-resistant salmonella enterica spp. enterica serovar 4,[5],12:i:- strains appeared as a novel serotype in germany, associated with large diffuse outbreaks and increased need for hospitalisation. the emerging 4,[5],12:i:- strains isolated from patients in germany belong mainly to phage type dt193 according to the anderson phage typing scheme for s. typhimurium (stm) and exhibit at least a tetra-drug resistance. the strains have been shown to harbour stm-specific gifs ...201020303825
neutrophil antimicrobial proteins enhance shigella flexneri adhesion and invasion.shigella flexneri is an enteric pathogen that causes massive inflammation and destruction of the human intestinal epithelium. neutrophils are the first cells of the innate immune system recruited to the site of infection. these cells can attack microbes by phagocytosis, neutrophil extracellular trap (net) formation and degranulation. here, we investigated how neutrophil degranulation affects virulence and show that exposure of shigella to granular proteins enhances infection of epithelial cells. ...201020331641
structure of shigella ipgb2 in complex with human rhoa: implications for the mechanism of bacterial guanine nucleotide exchange factor mimicry.a common theme in bacterial pathogenesis is the manipulation of eukaryotic cells by targeting the cytoskeleton. this is in most cases achieved either by modifying actin, or indirectly via activation of key regulators controlling actin dynamics such as rho-gtpases. a novel group of bacterial virulence factors termed the wxxxe family has emerged as guanine nucleotide exchange factors (gefs) for these gtpases. the precise mechanism of nucleotide exchange, however, has remained unclear. here we repo ...201020363740
isolation of bacteria from mouse caecal samples and description of bacteroides sartorii sp. nov.caecal samples from wild-type and tnf(deltaare) mice were cultured on selective media containing bile salts, amino acids or casein macro-peptides. twenty-two strains were isolated and identified by 16s rrna gene sequencing. twenty-one strains showed >98% similarity to known bacteria (blautia spp., clostridium innocuum, enterococcus spp., escherichia coli, lactobacillus murinus, parabacteroides goldsteinii and shigella dysenteriae). one additional isolate, strain a-c2-0, was a new bacterium. the ...201020369227
antibacterial effect of the bioactive compound beauvericin produced by fusarium proliferatum on solid medium of wheat.to obtain the bioactive compound beauvericin (bea), fusarium proliferatum cect 20569 was grown on a solid medium of wheat, utilizing the technique of the solid state fermentation (ssf), being this mycotoxin purified by high performance liquid chromatography (hplc) with a reverse phase semi-preparative column using as the mobile phase acetonitrile/water in gradient condition. the purity of the bea was verified by analytical hplc and liquid chromatography tandem mass spectrometry (lc/ms-ms). the p ...201020371252
the effects of a vegetable-derived probiotic lactic acid bacterium on the immune response.the objective of this study was to investigate the probiotic properties of the fermented vegetable derived lactic acid bacterium, l. plantarum. l. plantarum 10hk2 showed antibacterial activity against pathogenic bacteria and immunomodulating effects on murine macrophage cell lines. raw 264.7 cells stimulated with viable cells of this probiotic strain increased the amounts of pro-inflammatory mediators such as il-1beta, il-6 and tnf-alpha, as well as the anti-inflammatory mediator, il-10. icr mic ...201020377751
use of optical mapping to sort uropathogenic escherichia coli strains into distinct subgroups.optical maps were generated for 33 uropathogenic escherichia coli (upec) isolates. for individual genomes, the ncoi restriction fragments aligned into a unique chromosome map for each individual isolate, which was then compared with the in silico restriction maps of all of the sequenced e. coli and shigella strains. all of the upec isolates clustered separately from the shigella strains as well as the laboratory and enterohaemorrhagic e. coli strains. moreover, the individual strains appeared to ...201020378655
biological potentials and cytotoxicity of various extracts from endemic origanum minutiflorum o. schwarz & p.h. davis.the aim of the present study was to investigate antioxidative, antimicrobial and cytotoxic effects of endemic origanum minutiflorum (o. schwarz & p.h. davis). antioxidant activities of the extracts from o. minutiflorum were evaluated by using dpph radical scavenging, beta-carotene bleaching and metal chelating activity assays. in addition, the amounts of total phenol components in the plant extracts were determined. in the beta-carotene bleaching test, the extracts exhibited in the range of 58.1 ...201020381570
preliminary foodnet data on the incidence of infection with pathogens transmitted commonly through food - 10 states, 2009.the foodborne diseases active surveillance network (foodnet) of cdc's emerging infections program conducts active, population-based surveillance in 10 u.s. states for all laboratory-confirmed infections with select enteric pathogens transmitted commonly through food. this report describes preliminary surveillance data for 2009 and trends in incidence since 1996. in 2009, a total of 17,468 laboratory-confirmed cases of infection were identified. in comparison with the first 3 years of surveillanc ...201020395935
nmr characterization of the interaction of the salmonella type iii secretion system protein sipd and bile salts.salmonella and shigella bacteria require the type iii secretion system (t3ss) to inject virulence proteins into their hosts and initiate infections. the tip proteins sipd and ipad are critical components of the salmonella and shigella t3ss, respectively. recently, sipd and ipad have been shown to interact with bile salts, which are enriched in the intestines, and are hypothesized to act as environmental sensors for these enteric pathogens. bile salts activate the shigella t3ss but repress the sa ...201020397637
innate ifn-gamma production by subsets of natural killer cells, natural killer t cells and gammadelta t cells in response to dying bacterial-infected macrophages.interferon-gamma (ifn-gamma) activation of macrophages is a crucial step in the early innate defence against bacterial infection. this innate ifn-gamma is thought to be produced mainly by natural killer (nk) cells through activation with interleukin (il)-12p70 secreted by macrophages and dendritic cells (dcs) that have sensed bacterial products. however, a number of reports have shown that bacterial stimuli are unable to induce macrophages and/or dcs to produce sufficient amounts of il-12p70 unl ...201020415785
production and immunogenicity of recombinant ferric enterobactin protein (fepa).ferric siderophore complexes are produced by most bacteria to acquire iron, a vital element. these complexes are transported across the outer membrane by receptor proteins commonly known as fepa (ferric enterobactin protein). in this study we attempted to evaluate the immunogenicity of the membrane protein fepa, aiming at inhibition of iron uptake to protect invasion of the host by the bacterium.201020418143
tracking the secretion of fluorescently labeled type iii effectors from single bacteria in real time.a large number of gram negative pathogens use a specialized needle-like molecular machine known as type iii secretion (t3s) system. this highly sophisticated molecular device consists of a basal body spanning the two bacterial membranes and a protruding needle structure that is connected to a distal translocator complex. the main features of the t3s system are (i) activation after host cellular membrane contact and (ii) the ability to "inject" effectors into host cells through the needle apparat ...201020419414
isolation and selection of coliphages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing e. coli (ehec and stec) in cattle.to isolate, characterize and select phages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing escherichia coli (ehec and stec) in cattle.201020353429
molecular architecture of the mn2+-dependent lactonase ulag reveals an rnase-like metallo-beta-lactamase fold and a novel quaternary structure.the ulag gene, located in the ula regulon, is crucial for the catabolism of l-ascorbate under anaerobic conditions and it has been proposed to encode for the putative l-ascorbate-6-p lactonase. the ulag gene is widespread among eubacteria, including human commensal and pathogenic genera such as escherichia, shigella, klebsiella and salmonella. here, we report the three-dimensional structures of the apoenzyme and mn(2+) holoenzyme of ulag from e. coli to 2.6 a resolution, determined using single- ...201020359483
modeling fimbriae mediated parasite-host interactions.type 1 fimbriae are a known virulence factor in a number of pathogenic enterobacteriaceae, including salmonella, shigella and e. coli. yet, they are also expressed by some commensal strains, notably of e. coli. one hypothesis of the role of fimbriae in commensals is that they evoke a small but tolerable host immune response in order to have the host release sialic acid, which is a valuable nutrient. genetic evidence suggests that sialic acid down-regulates fimbriation. this has been believed to ...201020359486
a soluble form of the pilus protein fima targets the vdac-hexokinase complex at mitochondria to suppress host cell apoptosis.inhibition of apoptotic response of host cells during an early phase of infection is a strategy used by many enteroinvasive bacterial pathogens to enhance their survival. here, we report the identification of a soluble form of the pilus protein fima from the culture supernatants of e. coli k1, salmonella, and shigella that can potently inhibit bax-mediated release of cytochrome c from isolated mitochondria. similar to the infected cells, hct116 cells stably expressing fima display a delay in the ...201020347420
34 kda momp of shigella flexneri promotes tlr2 mediated macrophage activation with the engagement of nf-kappab and p38 map kinase signaling.the 34 kda major outer membrane protein (momp) of shigella flexneri 2a induces combinatorial expression of tlr2 and tlr6 on peritoneal macrophages of balb/c mice. between the two best-characterized tlrs, to date, tlr2 and tlr4, which are chiefly responsible for recognizing majority of bacterial products, tlr2 alone participates in recognition of 34 kda momp. in addition to tlrs, momp enhances the mrna expression of myd88 and traf6 and induces the nuclear translocation of nf-kappab as well as act ...201020347487
long-term downregulation of protease-activated receptor-2 expression in distal colon in rats following bacillary dysentery.the aim of this study was to determine changes of par-2 expression in distal colon and the sensitivity of colonic muscle to sligrl-nh2, the par-2-activating peptide (par-2-ap) following bacillary dysentery. shigella flexneri was administrated intragastrically in healthy male rats to induce bacillary dysentery. the effect of sligrl-nh2 on the motility of colonic muscle strips were examined. the expression of par-2 was determined by immunohistochemistry and western blotting. intragastric administr ...201020347884
antibiotics for the treatment of dysentery in children.ciprofloxacin, ceftriaxone and pivmecillinam are the antibiotics currently recommended by the world health organization (who) for the treatment of dysentery in children; yet there have been no reviews of the clinical effectiveness of these antibiotics in recent years.201020348130
global transcriptional response of macrophage-like thp-1 cells to shiga toxin type 1.shiga toxins (stxs) are bacterial cytotoxins produced by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli that cause bacillary dysentery and hemorrhagic colitis, respectively. to date, approaches to studying the capacity of stxs to alter gene expression in intoxicated cells have been limited to individual genes. however, it is known that many of the signaling pathways activated by stxs regulate the expression of multiple genes in mammalian cells. to ex ...201020351145
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
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
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
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
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
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
solution nmr structures of proteins vpa0419 from vibrio parahaemolyticus and yiis from shigella flexneri provide structural coverage for protein domain family pfam 04175. 201019927321
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
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
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
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
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
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
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
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
phenotypic and genotypic characterization of shigella spp. with reference to its virulence genes and antibiogram analysis from river narmada.water samples of the river narmada from origin to end were analyzed for the presence of shigellae. analysis of 40 water samples by biotyping, serotyping, and molecular typing were done. out of all 40 isolates, 23 were identified as shigella flexneri, 10 as shigella sonnei, and seven as shigella dysenteriae. serotyping was found to be a better identification method than biotyping since biotyping was not found to be very sharp. in the present investigation, amplified ribosomal dna restriction anal ...201019501495
lactobacilli inhibit shigella dysenteriae 1 induced pro-inflammatory response and cytotoxicity in host cells via impediment of shigella-host interactions.shigella dysenteriae type 1 dysentery is a major cause of morbidity and mortality in children from less developed and developing countries. the present study explores the hypothesis that lactobacilli protect the host cell during s. dysenteriae type 1 infection and its mechanism of action.201019535308
survey of bacterial populations present in us-produced linerboard with high recycle content.to survey paperboard products from 17 us mills for bacterial populations and for bacteria potentially harmful to human health.201019645765
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
biennial hyperepidemic shigellosis in an observant jewish community.we aimed to study patterns of shigellosis in a large observant jewish community in israel and to describe local interventions during outbreaks. surveillance data from the ministry of health were used to calculate incidence rates in 1998-2006, both in the city of bene beraq and the tel aviv district. information on isolates was collected from the bacteriological laboratory of a community hospital. public notices and educational conferences conveyed a message to increase personal hygiene and keep ...201019602299
etiology of childhood diarrhea in the northeast of brazil: significant emergent diarrheal pathogens.in a study conducted in joão pessoa, northeast of brazil, 2344 escherichia coli isolated from 290 infants with diarrhea and 290 healthy matched controls were analyzed for virulence traits. enteroaggregative e. coli (eaec) was the most prevalent pathogen associated to acute diarrhea. based on the results of colony blot hybridization, serotyping, and hep-2 cell adherence assays, strains were separated in categories as typical enteropathogenic e. coli (epec) (1.7%), atypical epec (a-epec) (9.3%), e ...201018508227
community perceptions of bloody diarrhoea in an urban slum in south asia: implications for introduction of a shigella vaccine.understanding local perceptions of disease causation could help public health officials improve strategies to prevent bloody diarrhoea. a cross-sectional survey was conducted in dhaka, bangladesh to elicit community beliefs about the causes of and prevention strategies for bloody diarrhoea. between march and june 2003, we interviewed 541 randomly selected respondents. overall, 507 (93%) respondents perceived that a vaccine could prevent bloody diarrhoea. if a vaccine provided lifetime protection ...201120546637
changing species distribution and antimicrobial susceptibility pattern of shigella over a 29-year period (1980-2008).we studied changes in species distribution and antimicrobial resistance patterns of shigella during 1980-2008, using the diarrhoeal diseases surveillance system of dhaka hospital of icddr,b. in hospitalized patients shigella prevalence decreased steadily from 8-12% in the 1980s to 3% in 2008. endemic s. flexneri was the most commonly isolated species (54%). epidemic s. dysenteriae type 1 had two peaks in 1984 and 1993, but was not found after 2000, except for one case in 2004. the therapeutic op ...201120478088
development of a pcr protocol for the detection of escherichia coli o157:h7 and salmonella spp. in surface water.escherichia coli o157:h7 and salmonella are pathogenic microorganisms that can cause severe gastrointestinal illness in humans. these pathogens may be transmitted in a variety of ways, including food and water. the presence of salmonella and e. coli o157:h7 in surface waters constitutes a potential threat to human health when used for either drinking or recreation. as with most waterborne pathogens, salmonella and e. coli o157:h7 are difficult to detect and enumerate with accuracy in surface wat ...201120714926
antidiarrheal activity, chemical and toxicity profile of berberis aristata.context: this study evaluated the in vitro and in vivo antidiarrheal activity, oral acute toxicological profile, and developed a chemical fingerprint of berberis aristata linn. (berberidaceae). materials and methods: the ethanol (by maceration) and aqueous (by soxhlet) extracts of berberis aristata bark were used for the study. the study involved the antimicrobial (minimum inhibitory concentration (mic) and minimum bactericidal concentration (mbc) by micro dilution) and antidiarrheal (castor oil ...201120738174
a disposable immunosensor for shigella flexneri based on multiwalled carbon nanotube/sodium alginate composite electrode.a novel shigella flexneri immunosensor based on horseradish peroxidase-labeled antibodies to s. flexneri (hrp-anti-s. flexneri) immobilized by physical adsorption on the multiwalled carbon nanotube (mwcnt)/sodium alginate (sa) composite modified screen-printed electrode surface was successfully fabricated. in this strategy, mwcnt/sa biocomposite acted as the matrix to adsorb and immobilize hrp-anti-s. flexneri. the modified electrodes were characterized with an atomic force microscope and cyclic ...201120816661
Morning Glory Resin Glycosides as Modulators of Antibiotic Activity in Multidrug-Resistant Gram-Negative Bacteria.Twenty-six microbiologically inactive (MIC >?512?µg/mL) convolvulaceous resin glycosides ( 1- 26) were tested for resistance modulatory activity IN VITRO against ESCHERICHIA COLI Rosetta-gami and two nosocomial pathogens, SALMONELLA TYPHI and SHIGELLA FLEXNERI. These compounds exerted a potentiation effect of the clinically useful antibiotics tetracycline, kanamycin, and chloramphenicol against the tested gram-negative bacteria by increasing antibiotic susceptibility up to 32-fold at concent ...201122002849
Development of a multiplex PCR assay targeting O-antigen modification genes for molecular serotyping of Shigella flexneri.Shigella flexneri is the major Shigella species that causes diarrheal disease in developing countries. It is further subdivided into 15 serotypes based on O-antigen structure. Serotyping of S. flexneri is important for epidemiological purposes. In this study, we developed a multiplex PCR assay targeting the O-antigen synthesis gene wzx and the O-antigen modification genes gtrI, gtrIC, gtrII, oac, gtrIV, gtrV, and gtrX for molecular serotyping of S. flexneri. The multiplex PCR assay contained eig ...201121880974
a case of reactive arthritis after salmonella enteritis in in a 12-year-old boy.reactive arthritis comprises a subgroup within infection-associated arthritides in genetically susceptible hosts. researchers and clinicians recognize two clinical forms of reactive arthritis which occurs after genitourinary tract infection and after gastrointestinal tract infection. chlamydia infection has been implicated as the most common agent associated with post-venereal reactive arthritis. studies have proposed shigella infection, salmonella infection, or yersinia infection as the microor ...201122025926
Use of a DNA microarray for detection and identification of bacterial pathogens associated with fishery products.We established a microarray for the simultaneous detection and identification of diverse putative pathogens often associated with fishery products by targeting specific genes of Listeria monocytogenes, Salmonella, Shigella, Staphylococcus aureus, Streptococcus pyogenes, Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, and Yersinia enterocolitica and the 16S-23S rRNA gene internal transcribed spacer (ITS) region of Proteus mirabilis and Proteus vulgaris. The microarray contained 26 sp ...201121965411
The iron-responsive Fur/RyhB regulatory cascade modulates the Shigella outer membrane protease IcsP.Actin-based motility is central to the pathogenicity of the intracellular bacterial pathogen Shigella. Two Shigella outer membrane proteins, IcsA and IcsP, are required for efficient actin-based motility in the host cell cytoplasm, and the genes encoding both proteins are carried on the large virulence plasmid. IcsA triggers actin polymerization on the surface of the bacterium, leading to the formation of an actin tail that allows both intra- and intercellular spread. IcsP, an outer membrane pro ...201121859852
rates of mutation and host transmission for an escherichia coli clone over 3 years.although over 50 complete escherichia coli/shigella genome sequences are available, it is only for closely related strains, for example the o55:h7 and o157:h7 clones of e. coli, that we can assign differences to individual evolutionary events along specific lineages. here we sequence the genomes of 14 isolates of a uropathogenic e. coli clone that persisted for 3 years within a household, including a dog, causing a urinary tract infection (uti) in the dog after 2 years. the 20 mutations observed ...201122046404
polyclonal antibody against conserved sequences of mce1a protein blocks mtb infection in macrophages.the pathogenesis of mycobacterium tuberculosis is largely due to its ability to enter and survive within human macrophages. it is suggested that a specific protein namely mammalian cell entry protein is involved in the pathogenesis and the specific gene for this protein mce1a has been identified in several pathogenic organisms such as rickettsia, shigella, escherichia coli, helicobacter, streptomyces, klebsiella, vibrio, neisseria, rhodococcus, nocardioides, saccharopolyspora erthyrae, and pseud ...201122159737
long-term trends in the epidemiology and resistance of childhood bacterial enteropathogens in crete.in this study, we investigated the long-term trends in the epidemiology and susceptibility of bacterial enteropathogens among children in a well-defined area of adequate health standards. the study included all children younger than 14 years of age treated for enteritis at heraklion university general hospital on the island of crete during the 18-year period from january 1993 to december 2010. stool specimens were tested for salmonella, shigella, campylobacter, enteropathogenic escherichia coli ...201122207394
structuring the bacterial genome: y1-transposases associated with rep-bime sequences{dagger}reps are highly repeated intergenic palindromic sequences often clustered into structures called bimes including two individual reps separated by short linker of variable length. they play a variety of key roles in the cell. reps also resemble the sub-terminal hairpins of the atypical is200/605 family of insertion sequences which encode y1 transposases (tnpa(is200/is605)). these belong to the huh endonuclease family, carry a single catalytic tyrosine (y) and promote single strand transposition. ...201122199259
Antibiotics shaping bacterial genome: deletion of an IS91 flanked virulence determinant upon exposure to subinhibitory antibiotic concentrations.The nucleoid-associated proteins Hha and YdgT repress the expression of the toxin a-hemolysin. An Escherichia coli mutant lacking these proteins overexpresses the toxin a-hemolysin encoded in the multicopy recombinant plasmid pANN202-312R. Unexpectedly, we could observe that this mutant generated clones that no further produced hemolysin (Hly(-)). Generation of Hly(-) clones was dependent upon the presence in the culture medium of the antibiotic kanamycin (km), a marker of the hha allele (hha::T ...201122096603
a 35 kda antigenic protein from shigella flexneri: in silico structural and functional studies.shigella flexneri serotype 2a is a major public health concern in the developing and under-developed countries which contributes to shigellosis endemic and mortality. thus, there is an urgent need for a rapid diagnostic test for effective therapy and disease management. previous study showed that a ∼35 kda antigenic protein from s. flexneri is a potential biomarker. we therefore modelled the three-dimensional structure of the antigen to probe its functionality which could aid in the development ...201121982766
A gyrB-targeted PCR for rapid identification of Salmonella.Salmonella causes the majority of infections in humans and homeothermic animals. This article describes a specific polymerase chain reaction (PCR) method developed for a rapid identification of Salmonella. A gyrB-targeted species-specific primer pair, S-P-for (5'-GGT GGT TTC CGT AAA AGT A-3') and S-P-rev (5'-GAA TCG CCT GGT TCT TGC-3'), was successfully designed. PCR with all the Salmonella strains produced a 366- bp DNA fragment that was absent from all the non-Salmonella strains tested. The de ...201121892633
Exploration of in vitro time point quantitative evaluation of newly synthesized benzimidazole and benzothiazole derivatives as potential antibacterial agents.Present communication deals with the in vitro time point quantitative antibacterial evaluation of newly synthesized 1,2-disubstituted benzimidazoles (3a-p) and 2-substituted benzothiazoles (5a-h) against Gram-positive bacteria Staphylococcus aureus, Bacillus cereus, and Gram-negative bacteria Vibrio cholerae, Shigella dysenteriae and Escherichia coli. These compounds were synthesized under mild reaction conditions using Al(2)O(3)-Fe(2)O(3) nanocrystals as heterogeneous catalyst. Bio-evaluation s ...201122047695
emergence of ceftriaxone resistant shigella.shigellosis is endemic in many resource-poor countries due to feco-oral transmission, resulting in considerable morbidity and mortality. there is rapid emergence of multi-drug resistant (mdr) shigella spp. resulting in poor reliability of first line antibiotics like quinolones, co-trimoxazole and ampicillin. ceftriaxone has been used as a reserved antibiotic for treatment of mdr shigella spp. the authors report a case of ceftriaxone resistant shigella flexneri successfully managed with meropenem ...201122205379
Autophagy as an innate immunity paradigm: expanding the scope and repertoire of pattern recognition receptors.Autophagy is rapidly developing into a new immunological paradigm. The latest links now include overlaps between autophagy and innate immune signaling via TBK-1 and IKKa/ß, and the role of autophagy in inflammation directed by the inflammasome. Autophagy's innate immunity connections include responses to pathogen and damage-associated molecular patterns including alarmins such as HMGB1 and IL-1ß, Toll-like receptors, Nod-like receptors including NLRC4, NLRP3 and NLRP4, and RIG-I-like receptors. ...201122118953
Two Cases of Hemorrhagic Diarrhea Caused by Cronobacter sakazakii in Hospitalized Nursing Infants Associated with the Consumption of Powdered Infant Formula.Two cases of acute gastroenteritis occurred in 5-month-old infants hospitalized in a mother-and-child hospital in Queretaro, Mexico, on 24 January 2010. C. sakazakii was recovered from the powdered infant formula (PIF), rehydrated PIF (R-PIF) fed to infants, and their fecal samples. The microorganism was present at levels of 0.33 most probable number (MPN)/g and 24 MPN/ml in PIF and R-PIF, respectively. The total ingested dose for the day before the onset of the diarrheic syndrome ranged betwee ...201122186061
Investigation of the binding of a carbohydrate-mimetic peptide to its complementary anticarbohydrate antibody by STD-NMR spectroscopy and molecular-dynamics simulations.Saturation transfer difference (STD)-NMR spectroscopy was used to probe experimentally the bioactive solution conformation of the carbohydrate mimic MDWNMHAA 1 of the O-polysaccharide of Shigella flexneri Y when bound to its complementary antibody, mAb SYA/J6. Molecular dynamics simulations using the ZymeCAD™ Molecular Dynamics platform were also undertaken to give a more accurate picture of the conformational flexibility and the possibilities for bound ligand conformations. The ligand topology, ...201121953925
a proteogenomic analysis of shigella flexneri using 2d lc-maldi tof/tof.new strategies for high-throughput sequencing are constantly appearing, leading to a great increase in the number of completely sequenced genomes. unfortunately, computational genome annotation is out of step with this progress. thus, the accurate annotation of these genomes has become a bottleneck of knowledge acquisition.201122032405
emergence of a novel shiga toxin-producing escherichia coli o serogroup cross-reacting with shigella boydii type 10.this is the first report of the isolation of shiga toxin-producing escherichia coli (stec) strains whose o antigens were genetically and serologically identical to those of shigella boydii type 10, from human feces. the novel stec o serogroup may be widespread in japan and associated with diarrhea and hemorrhagic colitis.201121865424
contribution of the lipopolysaccharide to resistance of shigella flexneri 2a to extreme acidity.shigella flexneri is endemic in most underdeveloped countries, causing diarrheal disease and dysentery among young children. in order to reach its target site, the colon, shigella must overcome the acid environment of the stomach. shigella is able to persist in this stressful environment and, because of this ability it can initiate infection following the ingestion of very small inocula. thus, acid resistance is considered an important virulence trait of this bacterium. it has been reported that ...201121984920
bacterial aetiology of diarrhoeal diseases and antimicrobial resistance in dhaka, bangladesh, 2005-2008.summaryinfectious diarrhoea caused by bacterial pathogens contributes to the high level of mortality in developing countries like bangladesh. following standard bacteriological procedures, a total of 14 428 bacterial pathogens were isolated from 56 132 stool samples and rectal swabs collected from diarrhoeal patients between 2005 and 2008. the rate of isolation and antimicrobial susceptibility data were retrospectively analysed for these isolates and among them vibrio spp. (42·9%) were the most ...201122040529
[Antibacterial activity of nanostructured silver gel].Evaluation of antimicrobial activity of L-cysteine silver gel against various species of pathogenic and opportunistic microorganisms.201121913399
Control of an outbreak of diarrhoea in a vascular surgery unit caused by a high-level clindamycin-resistant Clostridium difficile PCR ribotype 106.This report describes an outbreak of Clostridium difficile infection (CDI) in a vascular surgery ward in 2009 caused by a high-level clindamycin-resistant ribotype 106. A case of CDI was defined as a patient with diarrhoea, positive for C. difficile toxin and negative for other enteric pathogens. Cultures were sent to the Scottish Salmonella Shigella and Clostridium difficile Reference Laboratory (SSSCDRL) for PCR ribotyping, antibiotic susceptibility testing and PCR detection of ermB. The mean ...201121864938
phylogenetic characterization of bacteria in the gut of house flies (musca domestica l.).house flies (musca domestica l.) are cosmopolitan, ubiquitous, synanthropic insects that serve as mechanical or biological vectors for various microorganisms. to fully assess the role of house flies in the epidemiology of human diseases, it is essential to understand the diversity of microbiota harbored by natural fly populations. this study aimed to identify the diversity of house fly gut bacteria by both culture-dependent and culture-independent approaches. a total of 102 bacterial strains wer ...201122092755
dipstick test for rapid diagnosis of shigella dysenteriae 1 in bacterial cultures and its potential use on stool samples.we describe a test for rapid detection of s. dysenteriae 1 in bacterial cultures and in stools, at the bedside of patients.201121984895
antimicrobial resistance of shigella spp. isolated in the state of pará, brazil.shigella spp. are gram-negative, nonsporulating, rod-shaped bacteria that belong to the family enterobacteriaceae and are responsible for shigellosis or bacillary dysentery, an important cause of worldwide morbidity and mortality.201121860994
wide dissemination of multidrug-resistant shigella isolates in china.to evaluate the prevalence of antimicrobial resistance and selected antimicrobial resistance mechanisms in shigella isolates recovered in outpatients from 1997 to 2009 in china.201121859815
Sepsis-related myocardial calcification. 201121934087
outbreak of shigella sonnei infection in norway linked to consumption of fresh basil, october 2011.we report a shigella sonnei outbreak of 46 cases that occurred in norway during october 2011. two municipalities were involved. a large cluster (42 cases)was concentrated in north norway, while a smallcluster (4 cases) occurred in the south-east region.epidemiological evidence and trace back investigations have linked the outbreak to the consumption of imported fresh basil. the product has been withdrawn from the market. no further cases have been reported since 25 october.201122085618
prevalence and antimicrobial susceptibility patterns of shigella species at felege hiwot referral hospital, northwest ethiopia.shigella species infections coupled with increased levels of antimicrobial resistances are major public health problems in developing countries particularly in children.201121991758
foodborne-associated shigella sonnei, india, 2009 and 2010. 201122099103
evolutionary silence of the acid chaperone protein hdeb in enterohemorrhagic escherichia coli o157:h7.the periplasmic chaperones hdea and hdeb are known to be important for cell survival at low ph (ph<3) in escherichia coli and shigella spp. here we investigated the roles of hdea and hdeb in the survival of various enterohemorrhagic e. coli (ehec) following exposure to ph 2.0. similar to k-12 strains, the acid protections conferred by hdea and hdeb in ehec o145 were significant: loss of hdea and hdeb led to over 100- to 1000-fold reductions in acid survival, depending on the growth condition of ...201122179243
rational design of an artificial genetic switch: co-option of the h-ns-repressed prou operon by the virb virulence master regulator.the h-ns protein represses the transcription of hundreds of genes in gram-negative bacteria. derepression is achieved by a multitude of mechanisms, many of which involve the binding of a protein to dna at the repressed promoter in a manner that compromises the maintenance of the h-ns-dna nucleoprotein repression complex. the principal virulence gene promoters in shigella flexneri, the cause of bacillary dysentery, are repressed by h-ns. virb, a protein that closely resembles members of the parb ...201121873493
Crystal Structure of the VapBC Toxin-Antitoxin Complex from Shigella flexneri Reveals a Hetero-Octameric DNA-Binding Assembly.Toxin-antitoxin (TA) loci are common in archaea and prokaryotes and allow cells to rapidly adapt to changing environmental conditions through release of active regulators of metabolism. Many toxins are endonucleases that target cellular mRNA and tRNAs, while the antitoxins tightly wrap around the toxins to inhibit them under normal circumstances. The antitoxins also bind to operators in the promoter regions of the cognate TA operon and thereby regulate transcription. For enteric vapBC TA loci, t ...201122037005
applications of pcr (real-time and masstag) and enzyme-linked immunosorbent assay in diagnosis of respiratory infections and diarrheal illness among deployed u.s. military personnel during exercise balikatan 2009, philippines.laboratory-based surveillance for diarrheal and respiratory illness was conducted at the 2009 republic of the philippines-united states balikatan exercise to determine the presence of specific pathogens endemic in the locations where the military exercises were conducted. ten stool and 6 respiratory specimens were obtained from individuals meeting case definitions for diarrhea or respiratory illness. stool specimens were frozen in dry ice and remotely tested using enzyme-linked immunosorbent ass ...201122128641
the inhibitory activity of lactobacillus spp. isolated from breast milk on gastrointestinal pathogenic bacteria of nosocomial origin.milk acts as a mean for transporting many essential substances from the mother to the child. in human beings, milk includes several predominant bacteria, such as staphylococci, streptococci, micrococci, lactobacilli, enterococci, lactococci and bifidobacteria. besides, its intake favors the predominance of bifidobacteria and lactobacilli in the child's intestinal microbiota. the present work explores the isolation and selection of lactobacilli strains with probiotic potential, focusing in their ...201121846506
comparative genomic analysis of bacteriophage ep23 infecting shigella sonnei and escherichia coli.bacteriophage ep23 that infects escherichia coli and shigella sonnei was isolated and characterized. the bacteriophage morphology was similar to members of the family siphoviridae. the 44,077 bp genome was fully sequenced using 454 pyrosequencing. comparative genomic and phylogenetic analyses showed that ep23 was most closely related to phage so-1, which infects sodalis glossinidius and phage ssl-2009a, which infects engineered e. coli. genomic comparison indicated that ep23 and so-1 were very s ...201122203555
[Antimicrobial resistance profiles of Shigella spp. isolated from feces samples in Hacettepe University Ihsan Dogramaci Children's Hospital between 1999-2010].The symptoms of infections caused by Shigella spp. are diverse and may change from person to person. The choice of antibiotics as well as the prevention of the loss of fluid and electrolytes are important in the clinical recovery. The local resistance rates to antibiotics should be taken into consideration when planning empirical therapy. The aims of this retrospective study were to detect the in vitro antimicrobial susceptibility of 605 Shigella spp. strains isolated from feces samples of child ...201122090291
site-specific incorporation of photo-cross-linker and bioorthogonal amino acids into enteric bacterial pathogens.enteric bacterial pathogens are known to effectively pass through the extremely acidic mammalian stomachs and cause infections in the small and/or large intestine of human hosts. however, their acid-survival strategy and pathogenesis mechanisms remain elusive, largely due to the lack of tools to directly monitor and manipulate essential components (e.g., defense proteins or invasive toxins) participating in these processes. herein, we have extended the pyrrolysine-based genetic code expansion st ...201122084898
cloning, characterization and evaluation of potent inhibitors of shigella sonnei acetohydroxyacid synthase catalytic subunit.acetohydroxyacid synthase (ahas) is a thiamin diphosphate (thdp)- and flavin adenine dinucleotide (fad)-dependent plant and microbial enzyme that catalyzes the first common step in the biosynthesis of essential amino acids such as leucine, isoleucine and valine. to identify strong potent inhibitors against shigella sonnei (s. sonnei) ahas, we cloned and characterized the catalytic subunit of s. sonnei ahas and found two potent chemicals (khg20612, khg25240) that inhibit 87-93% s. sonnei ahas act ...201122015678
systematic review: the use of proton pump inhibitors and increased susceptibility to enteric infection.background: the use of proton pump inhibitors (ppis) is increasing worldwide. suppression of gastric acid alters the susceptibility to enteric bacterial pathogens. aim  this systematic review was undertaken to examine the relationship between ppi use and susceptibility to enteric infections by a specific pathogen based on published literature and to discuss the potential mechanisms of ppi enhanced pathogenesis of enteric infections. methods  pubmed, ovid medline databases were searched. search t ...201121999643
liver mass in a young adult. 201121943702
shigella flexneri infection generates the lipid pi5p to alter endocytosis and prevent termination of egfr signaling.the phosphoinositide metabolic pathway, which regulates cellular processes implicated in survival, motility, and trafficking, is often subverted by bacterial pathogens. shigella flexneri, a bacterium that causes dysentery, injects ipgd, a phosphoinositide phosphatase that generates the lipid phosphatidylinositol 5-phosphate (pi5p), into host cells, thereby activating the phosphoinositide 3-kinase-akt survival pathway. we show that epidermal growth factor receptor (egfr) is required for pi5p-depe ...201121934107
genomic characterization of enteroaggregative escherichia coli from children in mali.background. enteroaggregative escherichia coli (eaec) is a cause of epidemic and sporadic diarrhea, yet its role as an enteric pathogen is not fully understood. methods. we characterized 121 eaec strains isolated in 2008 as part of a case-control study of moderate to severe acute diarrhea among children 0-59 months of age in bamako, mali. we applied multiplex polymerase chain reaction and comparative genome hybridization to identify potential virulence factors among the eaec strains, coupled wit ...201122184729
synthesis and biological evaluation of some thiazolidinones as antimicrobial agents.a novel series of thiazolidinone derivatives namely 4-(4-dimethylamino-6-{4-[5-(4-ethylpiperazin-1-ylmethyl)-4-oxo-2-phenylthiazolidin-3-yl]-phenylamino}-[1,3,5]triazin-2-yloxy)-1-methyl-1h-quinolin-2-one have been synthesized from the key intermediate 4-[4-(4-aminophenylamino)-6-dimethylamino-[1,3,5]triazin-2-yloxy]-1-methyl-1h-quinolin-2-one (7). condensation reaction of compound 7 with different aldehyde derivatives were performed to obtain schiff base derivatives, which after cyclization gav ...201122182927
diarrhea associated with shigella in children and susceptibility to antimicrobials.objective: to evaluate the distribution and susceptibility to antimicrobials of shigella isolated from children with acute diarrhea and without diarrhea in teresina, state of piauí, brazil. methods: four hundred children aged up to 60 months were studied. stools were collected from all the patients between january 2004 and august 2007. shigella was identified by conventional methods and antibiogram and extended-spectrum beta-lactamase (esbl) were performed by agar diffusion. results: shigellosis ...201122089139
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