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culture-independent real-time pcr reveals extensive polymicrobial infections in hospitalized diarrhoea cases in kolkata, india.clin microbiol infect abstract: culture-independent identification of diarrhoeal aetiological agents was performed using dna harvested from diarrhoeal stool specimens with sybr-green-based real-time pcr targeting vibrio cholerae, vibrio parahaemolyticus, campylobacter spp., shigella spp. and three different pathotypes of diarrhoeagenic escherichia coli. conventional culture-dependent methods detected bacterial enteropathogens in 68 of 122 diarrhoeal stool specimens. of 68 specimens, 59 (86.8%) h ...201122268636
the patient presenting with acute dysentery - a systematic review.objectives: the etiologies, clinical presentations and diagnosis of acute pathogen-specific dysentery in children and adults in industrialized and developing regions is described to help develop recommendations for therapy. methods: we conducted a systematic review of literature published between january 2000 and june 2011 to determine the frequency of occurrence of pathogen-specific dysentery. results: shigella, salmonella, and campylobacter remain the most frequent bacterial causes of dysenter ...201222266388
the evolution of the escherichia coli phylogeny.escherichia coli are familiar to biologists as a classical model system, ubiquitous in molecular biology laboratories around the world. outside of the laboratory, e. coli strains exist as an almost universal component of the lower-gut flora of humans and animals. although usually a commensal, e. coli has an alter ego as a pathogen, and is associated with diarrhoeal disease and extra-intestinal infections. the study of e. coli diversity predates the availability of molecular data, with strains in ...201222266241
antimicrobial activity of ulopterol isolated from toddalia asiatica (l.) lam.: a traditional medicinal plant.aim of the study: the leaves of toddalia asiatica (l.) lam. (rutaceae) are widely used in folk medicine in india to treat various ailments. in our earlier communication we have reported the antimicrobial study on the various extracts of the leaves and the isolation and identification of flindersine, a quinolone alkaloid as the major active principle. in the present study, we report the antibacterial and antifungal activities of ulopterol, a coumarin isolated as another major active antimicrobial ...201222265751
epidemiological, clinical features and susceptibility pattern of shigellosis in the buea health district, cameroon.abstract: background: shigellosis is an acute invasive enteric infection caused by bacteria belonging to the genus shigella; it is clinically manifested by bloody diarrhoea. shigellosis is endemic in many developing countries including cameroon and also occurs in epidemics causing considerable morbidity and mortality. this study evaluated the epidemiological and clinical features of shigella and the resistance pattern of isolates to commonly used antibiotics in the buea health district in camer ...201222264300
antibacterial effect and cytotoxicity of beta-1,3-1, 4-glucanase from endophytic bacillus subtilis swb8.we studied the antibiotic activity and selective cytotoxicity of beta-1,3-1,4-glucanase from endophytic bacillus subtilis swb8.201122260051
galectin 8 targets damaged vesicles for autophagy to defend cells against bacterial invasion.autophagy defends the mammalian cytosol against bacterial infection. efficient pathogen engulfment is mediated by cargo-selecting autophagy adaptors that rely on unidentified pattern-recognition or danger receptors to label invading pathogens as autophagy cargo, typically by polyubiquitin coating. here we show in human cells that galectin 8 (also known as lgals8), a cytosolic lectin, is a danger receptor that restricts salmonella proliferation. galectin 8 monitors endosomal and lysosomal integri ...201222246324
evaluation of a quantitative h(2)s mpn test for fecal microbes analysis of water using biochemical and molecular identification.the sensitivity and specificity of the h(2)s test to detect fecal bacteria in water has been variable and uncertain in previous studies, partly due to its presence-absence results. furthermore, in groundwater samples false-positive results have been reported, with h(2)s-positive samples containing no fecal coliforms or escherichia coli. false-negative results also have been reported in other studies, with h(2)s-negative samples found to contain e. coli. using biochemical and molecular methods an ...201222244995
[characterisation of a ctx-m-15-producing shigella sonnei in a spanish patient who had not travelled abroad.]one hundred and seven shigella spp. strains were isolated in our laboratory during the years 2000 to 2010. one shigella sonnei harboured the genes that coded the β-lactamases tem-1 and ctx-m-15, identifying the structure, isecp1+bla(ctx-m-15)+orf477, in their genetic environment. the strain also carried a class 2 integron with the gene cassettes dfra1+sat+aada1. a plasmid group inci1 st31 (cc-31) was detected and its mobilization by conjugation was demonstrated. we describe for the first time a ...201222244530
analysis of the global transcriptional profiles of enterotoxigenic escherichia coli (etec) isolate e24377a.enterotoxigenic escherichia coli (etec) is an important pathogenic variant (pathovar) of e. coli in developing countries from a human health perspective, causing significant morbidity and mortality. previous studies have examined specific regulatory networks in etec, although little is known about the global effects of inter- and intra-kingdom signaling on the expression of virulence and colonization factors in etec. in this study, an e.coli/shigella pan-genome microarray, combined with quantita ...201222215741
Genesis of a novel Shigella flexneri serotype by sequential infection of serotype-converting bacteriophages SfX and SfI.ABSTRACT: BACKGROUND: Shigella flexneri is the major pathogen causing bacillary dysentery. Fifteen serotypes have been recognized up to now. The genesis of new S. flexneri serotypes is commonly mediated by serotype-converting bacteriophages. Untypeable or novel serotypes from natural infections had been reported worldwide but have not been generated in laboratory. RESULTS: A new S. flexneri serotype-serotype 1 d was generated when a S. flexneri serotype Y strain (native LPS) was sequentially in ...201122208551
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
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
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
a broadly protective shigella vaccine based on type iii secretion apparatus proteins.shigella ssp. are food and water-borne pathogens that cause severe diarrheal and dysenteric disease associated with high morbidity and mortality. individuals most often affected are children under 5 years of age in the developing world. the existence of multiple shigella serotypes and the heterogenic distribution of pathogenic strains as well as emerging antibiotic resistance require the development of a broadly protective vaccine. all shigella ssp. utilize a type iii secretion system (ttss) to ...201122202122
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
Reactor performance and bacterial pathogen removal in response to sludge retention time in a mesophilic anaerobic digester treating sewage sludge.The effects of sludge retention time (SRT) on reactor performance and bacterial pathogen removal of sludge mesophilic anaerobic digestion (MAD) were investigated in a continuous stirred tank reactor. The average volatile solids removal remained around 20% and the biogas production rate varied from 100 to 132ml/ld. The MAD process was efficient to remove Salmonella sp. and Escherichia coli with removal efficiencies increased with SRT from 11d, 16d to 25d. However, the Shigella sp. removal was ins ...201122197074
How We Didn't Clean Up Until We Washed Our Hands: Shigellosis in an Elementary and Middle School in North Texas.Shigella outbreaks often continue for months and are linked frequently to poor hygiene and hand washing. Such outbreaks are found often in day care facilities, but rarely are reported in schools. We present the investigation of an outbreak in autumn 2007 at a building that housed an elementary school and a middle school in separate wings in a small Texas city north of Dallas-Fort Worth.201222189658
topological characterisation and identification of critical domains within glucosyltransferase iv (gtriv) of shigella flexneri.abstract:201122188643
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
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
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
Gut microbiota and pediatric disease.Background: Researchers have made every effort to assess the role of gut microbiota in pediatric diseases like inflammatory bowel disease (IBD), celiac disease, asthma, allergy, and autism. The leading hypothesis is that an altered microbial composition is present (other than the presence of a specific pathogen) and that it could be involved in the pathogenesis or progression of such disorders. Methods: Cultural, molecular, metabolomic, and metagenomic approaches are trying to define the pediatr ...201122179208
[etiological surveillance and analysis of infectious diarrhea in beijing in year 2010].to explore the pathogenic form, epidemic features and serotype distribution of the pathogenic bacteria causing infectious diarrhea in beijing.201122177306
Nicotinamide dependence of uropathogenic Escherichia coli UTI89 and application of nadB as a neutral insertion site.NAD and NADP function ubiquitously in the metabolism of Escherichia coli K-12. NAD auxotrophy can be rendered by mutation in any of the three genes, nadB, nadA, and nadC. The nadB and nadA genes were defined as anti-virulence loci in Shigella spp., as a mutation (mainly in nadB) disrupting the synthesis of quinolinate is required for virulence. Uropathogenic E. coli (UPEC) isolates, from acute cystitis patients, exhibiting nicotinamide auxotrophy were of serotype O18:K1:H7. E. coli UTI89, the mo ...201122174382
The effects of solid media type on routine identification of bacterial isolates using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry.Background: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis is a rapid method for the identification of bacteria based upon the comparison of protein profiles. Factors that may alter profiles include culture conditions and presence of exogenous substances and could hinder identification. Methods: Bacterial isolates identified using conventional methods were cultured on various media and identified using the MALDI Biotyper system (Bruker Dalton ...201122162546
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
an inverse and independent association between helicobacter pylori infection and the incidence of shigellosis and other diarrheal diseases.objectives. we examined the association between helicobacter pylori infection and the incidence of diarrheal diseases.methods. in a nested case-control study participants were sampled from cohorts of male israeli soldiers aged 18-21 years, serving in field units and followed up for diarrheal diseases. case patients (n = 177) were subjects who visited the base clinic because diarrhea and were positive for shigella sonnei (n = 66), enterotoxigenic escherichia coli (etec) (n = 31) or negative for b ...201122157171
Molecular Techniques in Ecohealth Research Toolkit: Facilitating Estimation of Aggregate Gastroenteritis Burden in an Irrigated Periurban Landscape.Assessment of microbial hazards associated with certain environmental matrices, livelihood strategies, and food handling practices are constrained by time-consuming conventional microbiological techniques that lead to health risk assessments of narrow geographic or time scope, often targeting very few pathogens. Health risk assessment based on one or few indicator organisms underestimates true disease burden due a number of coexisting causative pathogens. Here, we employed molecular techniques i ...201122146856
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
Atypical Shigella boydii 13 encodes virulence factors seen in attaching and effacing Escherichia coli.Enterohemorrhagic E. coli (EHEC) is a foodborne pathogen that causes watery diarrhea and hemorrhagic colitis. In this study, we identified StcE, a secreted zinc metalloprotease that contributes to intimate adherence of EHEC to host cells, in culture supernatants of atypical Shigella boydii 13 (Shigella B13) strains. Further examination of the Shigella B13 strains revealed that this cluster of pathogens does not invade but forms pedestals on HEp-2 cells similar to EHEC and enteropathogenic E. col ...201122126649
reflectron maldi tof and maldi tof/tof mass spectrometry reveal novel structural details of native lipooligosaccharides.lipooligosaccharides (los) are powerful gram-negative glycolipids that evade the immune system and invade host animal and vegetal cells. the structural elucidation of los is pivotal to understanding the mechanisms of infection at the molecular level. the amphiphilic nature of los has been the main obstacle for structural analysis by matrix-assisted laser desorption/ionization (maldi) mass spectrometry (ms). our approach has resolved this important issue and has permitted us to obtain reflectron ...201122124985
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
analysis of synonymous codon usage in shigella flexneri 2a strain 301 and other shigella and escherichia coli strains.in this study, we analysed synonymous codon usage in shigella flexneri 2a strain 301 (sf301) and performed a comparative analysis of synonymous codon usage patterns in sf301 and other strains of shigella and escherichia coli. although there was a significant variety in codon usage bias among different sf301 genes, there was a slight but observable codon usage bias that could primarily be attributable to mutational pressure and translational selection. in addition, the relative abundance of dinuc ...201122112197
gene decay in shigella as an incipient stage of host-adaptation.background: many facultative bacterial pathogens have undergone extensive gene decay processes, possibly due to lack of selection pressure during evolutionary conversion from free-living to intracellular lifestyle. shigella, the causative agents of human shigellosis, have arisen from different e. coli-like ancestors independently by convergent paths. as these bacteria all have lost large numbers of genes by mutation or deletion, they can be used as ideal models for systematically studying the pr ...201122110755
Differential host immune responses to epidemic and endemic strains of Shigella dysenteriae type I.Shigella dysenteriae type 1 causes devastating epidemics in developing countries with high case-fatality rates in all age-groups. The aim of the study was to compare host immune responses to epidemic (T2218) and endemic strains of S. dysenteriae type 1. Shigellacidal activity of serum from rabbits immunized with epidemic or endemic strains, S. dysenteriae type 1-infected patients, and healthy adult controls from Shigella-endemic and non-endemic regions was measured. Immunogenic cross-reactivity ...201122106748
A new piece of the Shigella pathogenicity puzzle: spermidine accumulationby silencing of the speG gene.The genome of Shigella, a gram negative bacterium which is the causative agent of bacillary dysentery, shares strong homologies with that of its commensal ancestor, Escherichia coli. The acquisition, by lateral gene transfer, of a large plasmid carrying virulence determinants has been a crucial event in the evolution towards the pathogenic lifestyle and has been paralleled by the occurrence of mutations affecting genes, which negatively interfere with the expression of virulence factors. In this ...201122102881
foodborne-associated shigella sonnei, india, 2009 and 2010. 201122099103
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
Evolutionary and functional insights into Leishmania META1: evidence for lateral gene transfer and a role for META1 in secretion.ABSTRACT: BACKGROUND: Leishmania META1 has for long been a candidate molecule for involvement in virulence: META1 transcript and protein are up-regulated in metacyclic Leishmania. Yet, how META1 contributes to virulence remains unclear. We sought insights into the possible functions of META1 by studying its evolutionary origins. RESULTS: Using multiple criteria including sequence similarity, nucleotide composition, phylogenetic analysis and selection pressure on gene sequence, we present evide ...201122093578
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
[Protozoal antigen positivity in diarrheal patients admitted to emergency service: a point prevalence study].Intestinal parasites are the important etiological agents of water and food related diarrhea cases which are frequently seen during summer/early autumn seasons in developing countries. This point prevalence study was aimed to determine the protozoal antigen positivity rate in diarrhea cases admitted to the emergency service in one single day. A total of 198 diarrheal patients (90 male, 108 female; age range: 1-82 years, mean age: 29 years) who were admitted to the emergency service of Ankara Tra ...201122090311
[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
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
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
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
approach to the patient with infectious colitis.to provide current recommendations for evaluation and treatment of patients with infectious colitis. infectious colitis is diagnosed in someone with diarrhea and one or more of the following: fever and/or dysentery, stools containing inflammatory markers such as leukocytes, lactoferrin, or calprotectin, or positive stool culture for an invasive or inflammatory bacterial enteropathogen including shigella, salmonella, campylobacter, shiga toxin-producing escherichia coli (stec) or clostridium diff ...201222080825
synthesis of novel quinoxalinone derivatives by conventional and microwave methods and assessing their biological activity.in this study, twenty-one arylaminoquinoxalinone derivatives were synthesized and their antibacterial activities against staphylococci aureus, pseudomonas aureus, escherichia coli, bacillus subtilis, salmonella typhi, and shigella pneumoniae were evaluated relative to known antibiotics; augmentin, ampicillin, and chloramphenicol. the insecticidal activities of the prepared compounds were also investigated against tribolium castaneum using permethrin as a standard insecticide. the derivatives wer ...201122076760
Simultaneous Detection of Six Diarrhea-Causing Bacterial Pathogens with an In-House PCR-Luminex Assay.Diarrhea can be caused by a range of pathogens, including several bacteria. Conventional diagnostic methods, such as culture, biochemical tests, and enzyme-linked immunosorbent assay (ELISA), are laborious. We developed a 7-plex PCR-Luminex assay to simultaneously screen for several of the major diarrhea-causing bacteria directly in fecal specimens, including pathogenic Aeromonas, Campylobacter jejuni, Campylobacter coli, Salmonella, Shigella, enteroinvasive Escherichia coli (EIEC), Vibrio, and ...201222075596
up-regulation of muc2 and il-1β expression in human colonic epithelial cells by shigella and its interaction with mucins.the entire gastrointestinal tract is protected by a mucous layer, which contains complex glycoproteins called mucins. muc2 is one such mucin that protects the colonic mucosa from invading microbes. the initial interaction between microbes and mucins is an important step for microbial pathogenesis. hence, it was of interest to investigate the relationship between host (mucin) and pathogen interaction, including shigella induced expression of muc2 and il-1β during shigellosis.201122073249
shiga toxins: intracellular trafficking to the er leading to activation of host cell stress responses.despite efforts to improve hygenic conditions and regulate food and drinking water safety, the enteric pathogens, shiga toxin-producing escherichia coli (stec) and shigella dysenteriae serotype 1 remain major public health concerns due to widespread outbreaks and the severity of extra-intestinal diseases they cause, including acute renal failure and central nervous system complications. shiga toxins are the key virulence factors expressed by these pathogens mediating extra-intestinal disease. de ...201022069648
shiga toxin is transported into the nucleoli of intestinal epithelial cells via a carrier-dependent process.shiga toxin (stx) produced by the invasive shigella dysenteriae serotype 1 (s. dysenteriae1) causes gastrointestinal and kidney complications. it has been assumed that stx is released intracellularly after enterocyte invasion by s. dysenteriae1. however, there is little information about stx distribution inside s. dysenteriae1-infected enterocytes. here, we use intestinal epithelial t84 cells to characterize the trafficking of stx delivered into the cytosol, in ways that mimic aspects of s. dyse ...201022069640
serine protease autotransporters of enterobacteriaceae (spates): biogenesis and function.serine protease autotransporters of enterobacteriaceae (spates) constitute a large family of proteases secreted by escherichia coli and shigella. spates exhibit two distinct proteolytic activities. first, a c-terminal catalytic site triggers an intra-molecular cleavage that releases the n-terminal portion of these proteins in the extracellular medium. second, the secreted n-terminal domains of spates are themselves proteases; each contains a canonical serine-protease catalytic site. some of thes ...201022069633
application of a multiplex pcr for the simultaneous detection of escherichia coli o157:h7, salmonella and shigella in raw and ready-to-eat meat products.escherichia coli o157:h7, salmonella and shigella might contaminate similar types of meat products and cause deadly diseases in humans. traditional microbiological analyses to detect these pathogens are labor-intensive and time-consuming. the objective of this study was to apply a multiplex pcr for simultaneous detection of the pathogenic bacteria in certain raw and ready-to-eat meat matrices. the tested samples had aerobic plate counts ranging from non-detectable, in chicken nuggets and salami, ...200522064243
Detection of diarrhoeal pathogens in human faeces using an automated, robotic platform.Infectious diarrhoeal diseases represent a major socio-economic burden to humans, and are linked to a range of pathogens, including viruses, bacteria and protists. The accurate detection of such pathogens is central to control. However, detection often relies on methods that have limited diagnostic sensitivity and specificity. Here, we assessed an automated, robotic platform for the simultaneous detection of eight major pathogens associated with infectious diarrhoea. Genomic DNA samples (n = 167 ...201122056326
microbial aspects of protein recovery from meat industry by-products.a significant reduction in the number of micro-organisms associated with the bovine meat by-products, lung, rumen and blood plasma, was noted after their alkali-extractable proteins had been spun into a fibrous form. most of the effect was found when the protein was coagulated in a 10% acetic acid/10% sodium chloride bath. whereas the approximate shelf-life of raw rumen and lung was three and four days, respectively (at 0°c), proteins isolated from these tissues were relatively stable and could ...197922055264
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
salmonella typhimurium-specific bacteriophage φsh19 and the origins of species specificity in the vi01-like phage family.whole genome sequencing of bacteriophages suitable for biocontrol of pathogens in food products is a pre-requisite to any phage-based intervention procedure. trials involving the biosanitization of salmonella typhimurium in the pig production environment identified one such candidate, φsh19.201122047448
[Etiological aspects of acute gastroenteritis--a ten-year review (1.01. 2001-31.12.2010)].Acute gastroentritis is one of the most common diseases in humans, and continues to be a significant cause of morbidity worldwide.201122046776
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
intestinal parasitosis and shigellosis among diarrheal patients in gondar teaching hospital, northwest ethiopia.abstract:201122041102
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
validation of the h2s method to detect bacteria of fecal origin by cultured and molecular methods.using biochemical and molecular methods, this research determined whether or not the h(2)s test did correctly identify sewage-contaminated waters by being the first to use culturing and molecular methods to identify the types and numbers of fecal indicator organisms, pathogens, and other microbes present in sewage samples with positive h(2)s test results. for the culture-based method, samples were analyzed for the presence of fecal bacteria by spread plating the sewage sample onto differential a ...201122038242
The scope of phage display for membrane proteins.Numerous examples of phage display applied to soluble proteins demonstrate the power of the technique for protein engineering, affinity reagent discovery and structure-function studies. Recent reports have expanded phage display to include membrane proteins (MPs). The scope and limitations of MP display remain undefined. Therefore, we report data from the phage display of representative types of membrane-associated proteins including plasma, nuclear, peripheral, single and multipass. The periphe ...201122037583
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
Within-species lateral genetic transfer and the evolution of transcriptional regulation in Escherichia coli and Shigella.Changes in transcriptional regulation underlie many of the phenotypic differences observed within and between species of bacteria. Lateral genetic transfer (LGT) can significantly impact the transcription factor (TF) genes which drive these transcriptional changes. Although much emphasis has been placed on LGT of intact genes, the units of transfer and recombination do not necessarily correspond to regions delineated by exact gene boundaries. Here we apply phylogenetic and network-based methods ...201122035052
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
Misidentification of a commensal inactive Escherichia coli as Shigella sonnei by an automated system in a critically ill patient.Though automated identification and sensitivity testing has established itself as a standard in many high throughput clinical microbiology laboratories, misidentification by the automated systems can also happen.201122029193
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
characterization and comparative genomic analysis of a novel bacteriophage, sfp10, simultaneously inhibiting both salmonella enterica and escherichia coli o157:h7.salmonella enterica and escherichia coli o157:h7 are major food-borne pathogens causing serious illness. phage sfp10, which revealed effective infection of both s. enterica and e. coli o157:h7, was isolated and characterized. sfp10 contains a 158-kb double-stranded dna genome belonging to the vi01 phage-like family myoviridae. in vitro adsorption assays showed that the adsorption constant rates to both salmonella enterica serovar typhimurium and e. coli o157:h7 were 2.50 × 10(-8) ml/min and 1.91 ...201222020516
Acid-bile, antibiotic resistance and inhibitory properties of propionibacteria isolated from Turkish traditional home-made cheeses.In this study, a total of 29 Propionibacterium spp. were isolated from traditional home-made Turkish cheese samples. As a result of the identification, isolates were identified as Propionibacterium freudenreichii subsp. freudenreichii (15 strains), Propionibacterium jensenii (12), and Propionibacterium thoenii (2). All isolates and 5 reference strains were examined for their abilities to survive at pH 2.0, 3.0, 4.0, 5.0 and in the presence of 0.06, 0.15 and 0.30% bile salts, their influence on t ...201122019987
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
the role of oxyr and soxrs in oxidative stress survival in shigella flexneri.shigella flexneri, a facultative intracellular pathogen, is exposed to a variety of environments inside and outside of the human host. some of these environments may contain significant oxidative stress. s. flexneri mutants were generated with deletions in the major oxidative stress regulators oxyr and/or soxrs to test their importance in shigella biology. strains that contained a deletion of oxyr had reduced growth and survival during aerobic growth, but not microaerobic growth. the mutants wer ...201122015257
toxic megacolon.toxic megacolon represents a dreaded complication of mainly inflammatory or infectious conditions of the colon. it is most commonly associated with inflammatory bowel disease (ibd), i.e., ulcerative colitis or ileocolonic crohn's disease. lately, the epidemiology has shifted toward infectious causes, specifically due to an increase of clostridium difficile-associated colitis possibly due to the extensive (ab)use of broad-spectrum antibiotics. other important infectious etiologies include salmone ...201122009735
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
antisense inhibition of gene expression and growth in gram-negative bacteria by cell-penetrating peptide conjugates of peptide nucleic acids targeted to rpod gene.gram-negative bacteria (gnb) cause common and severe hospital- and community-acquired infections with a high incidence of multidrug resistance (mdr) and mortality. the emergence and spread of mdr-gnb strains limit therapeutic options and highlight the need to develop new therapeutic strategies. in this study, the peptide (rxr)(4)xb- and (kff)(3)k-conjugated peptide nucleic acids (ppnas) were developed to target rpod, which encodes an rna polymerase primary σ(70) that is thought to be essential f ...201122000398
global distribution of shigella sonnei clones.to investigate global epidemiology of shigella sonnei, we performed multilocus variable number tandem repeat analysis of 1,672 isolates obtained since 1943 from 50 countries on 5 continents and the pacific region. three major clonal groups were identified; 2 were globally spread. type 18 and its derivatives have circulated worldwide in recent decades.201122000369
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
a school outbreak of shigella sonnei infection in china: clinical features, antibiotic susceptibility and molecular epidemiology.objective: to describe the clinical features of infection, and the antibiotic susceptibility of epidemic strains, and investigate plasmid maps and integrons of the isolates from an outbreak of shigella sonnei infection at an elementary school in southwest china. study design: cross-sectional study. setting: an elementary school and five hospitals in chengdu in southwest china. results: there were 1,134 students in the school. 937 (82.6%) students had signs and symptoms. of the 568 (60.6%, 568/93 ...201121992857
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
Molecular mechanism of multi-drug resistance in Shigella isolates from rural China.Diarrhoeal diseases and enteric infections are major causes of morbidity and mortality in the developing countries. Shigellosis was sixth in the rank of death caused by infectious disease in China. Present study assess the patterns of antimicrobial susceptibility and mutations in marA genes of Shigella isolates and its association. One hundred isolates of Shigella spp were tested to evaluate the antimicrobial susceptibility and mutation of marA through PCR-SSCP. The antimicrobial resistance prof ...201121991697
antibacterial characteristics and activity of water-soluble chitosan derivatives prepared by the maillard reaction.the antibacterial activity of water-soluble chitosan derivatives prepared by maillard reactions against staphylococcus aureus, listeria monocytogenes, bacillus cereus, escherichia coli, shigella dysenteriae, and salmonella typhimurium was examined. relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. in addition, it was found that the susceptibility of the test organisms to the water-solu ...201121989311
social-economic factors and irrational antibiotic use as reasons for antibiotic resistance of bacteria causing common childhood infections in primary healthcare.the most prevalent childhood bacterial infections in primary healthcare are respiratory, gastrointestinal and urogenital infections. the main aim of this paper was to consider factors (socio-economic factors and irrational antibiotic use) that contribute to the development of bacterial resistance, as well as measures that resulted in a reduction of this problem. computerized search through the medline of published articles on antibiotic resistance from 1996 to 2011 in english or serbian was comp ...201121987082
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
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
interaction of concanavalin a with bacterial lipopolysaccharides in agarose gel.binding of fluorescein isothiocyanate-labeled concanavalin a to a series of molecular species of lipopolysaccharide (lps), purified from pathogenic bacteria, was studied via agarose gel precipitation experiments and the results were compared with available structural data.the lps species could be divided into cona-reactive and non-reactive ones. reactivity resided in the o-specific chain of lps, and binding to the lipid a or core moieties of lps could not be demonstrated by the present methods. ...201121983321
Further characterization of Shigella sonnei live vaccine candidates WRSs2 and WRSs3-plasmid composition, invasion assays and Sereny reactions. 201121983066
Clinical characteristics and antibiotic resistance of Shigella gastroenteritis in Ankara, Turkey between 2003 and 2009, and comparison with previous reports.The aim of this study was to define the epidemiological, clinical, and antibiotic susceptibility patterns of Shigella gastroenteritis cases occurring during the years 2003-2009 and to compare results with those of the years 1987-2002.201121982814
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
convergent synthesis of the tetrasaccharide repeating unit of the o-antigen of shigella boydii type 9.a convenient synthesis of the tetrasaccharide repeating unit of the o-antigen of shigella boydii type 9 has been achieved in excellent yield using a [2 + 2] block glycosylation strategy. tempo-mediated selective oxidation of the primary alcohol of the tetrasaccharide derivative 8 to the carboxylic group followed by deprotection of the functional groups furnished target tetrasaccharide 1 as its 4-methoxyphenyl glycoside in high yield.201121977201
antibacterial and anti-inflammatory activity of traditional chinese herb pairs, angelica sinensis and sophora flavescens.the purpose of the present study was to investigate the antibacterial and anti-inflammatory activity of angelica sinensis extract (ae), sophora flavescens extract (se), and herb pair a. sinensis and s. flavescens extract (hpe). endotoxin-induced uveitis (eiu) was induced in rats by a footpad injection of lipopolysaccharide. the anti-inflammatory potential of ae, se, and hpe in the regulation of nuclear factor kappa b (nf-κb), maleic dialdehyde (mda), polymorphonuclear cells (pmn), interleukin-1β ...201121976127
Genotyping of selected bacterial enteropathogens in Norway.In Norway the Norwegian Institute of Public Health (NIPH) is the primary facility for nationwide surveillance of foodborne infections, and it is vital that we can perform rapid and high resolution identification of foodborne bacteria at the strain level. During the last decade a rapid introduction of DNA-based methods has been introduced, which show promise in enhancing the speed and discriminatory capability of the typing laboratory. The laboratory responsible for genotyping enteropathogens at ...201121975141
live attenuated shigella dysenteriae type 1 vaccine strains overexpressing shiga toxin b subunit.shigella dysenteriae serotype 1 (s. dysenteriae 1) is unique among the shigella species and serotypes in the expression of shiga toxin which contributes to more severe disease sequelae and the ability to cause explosive outbreaks and pandemics. s. dysenteriae 1 shares characteristics with other shigella species, including the capability of causing clinical illness with a very low inoculum (10 to 100 cfu) and resistance to multiple antibiotics, underscoring the need for efficacious vaccines and t ...201121969003
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
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
liver mass in a young adult. 201121943702
bacteriological assessment of drinking water supply options in coastal areas of bangladesh.this study was conducted to assess the bacteriological quality of alternative drinking water supply options in southwest coastal areas of bangladesh. a total of 90 water samples were collected during both dry and wet seasons from household based rainwater harvesting systems (rwhss), community based rain water harvesting systems (crwhss), pond-sand filters (psfs) and ponds. the samples were evaluated for faecal coliform, escherichia coli and heterotrophic plate count, as well as vibrio cholerae, ...201121942205
Comparative evaluation of the antibody in lymphocyte supernatant (ALS) and enzyme-linked immunospot (ELISPOT) assays for measuring mucosal immune responses to Shigella antigens.Accurately assessing mucosal immune responses to candidate vaccines remains a technical challenge. ELISPOT is widely used as a surrogate of mucosal immune response by directly enumerating circulating antibody secreting cells (ASCs), while antibody in lymphocyte supernatant (ALS) titers the total amount of antibody secreted by ASC ex vivo using ELISA. ALS is more practical than ELISPOT because the ASC supernatant is frozen for ELISA that can be conducted at any time, with any antigen, and in any ...201121939714
Rotavirus in adults requiring hospitalization.To determine the prevalence and epidemiological characteristics of rotavirus among adults admitted to the hospital with diarrhea that have bacterial stool cultures sent.201221939687
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