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shiga toxins induce autophagy leading to differential signalling pathways in toxin-sensitive and toxin-resistant human cells.the bacterial virulence factors shiga toxins (stxs) are expressed by shigella dysenteriae serotype 1 and certain escherichia coli strains. stxs are protein synthesis inhibitors and induce apoptosis in many cell types. stxs induce apoptosis via prolonged endoplasmic reticulum stress signalling to activate both extrinsic and intrinsic pathways in human myeloid cells. studies have shown that autophagy, a lysosome-dependent catabolic process, may be associated with activation of pro-survival or deat ...201121722286
structural characterization and membrane localization of exsb from the type iii secretion system (t3ss) of pseudomonas aeruginosa.pseudomonas aeruginosa is an opportunistic human pathogen that employs a finely tuned type iii secretion system (t3ss) to inject toxins directly into the cytoplasm of target cells. exsb is a 15.6-kda protein encoded in a t3ss transcription regulation operon that displays high sequence similarity to yscw, a lipoprotein from yersinia spp. whose genetic neighborhood also involves a transcriptional regulator, and has been shown to play a role in the stabilization of the outer membrane ring of the t3 ...201121839744
molecular characterization of fecal microbiota in patients with viral diarrhea.the study provides molecular analyses of fecal microbiota of diarrhea patients infected with four different types of viruses. fecal specimens from 52 patients with viral diarrhea (13 each of adenovirus, norovirus, rotavirus, and astrovirus) and six healthy individuals were collected and etiological viral agent was confirmed by enzyme immunoassay and specific pcr. to assess the changes in microbial diversity in patients with viral diarrhea, dna from stool were extracted and characterized by pcr-d ...201121739252
the effect of quercus castaneifolia extract on pathogenic enteric bacteria.the family of enterobacteriaceae is a major group of gram negative bacteria, some of these microorganisms are pathogen and could cause disease mainly gastroenteritis. recently, due to drug resistant nature of these bacteria specially in developing countries treatment of the patient considered as important investigate. quercus castaneifolia is a native plant of yasuj province in iran, which the people who living in this area consume the fruit of this plant for treatment of enteric disease. hence, ...201121827865
viral-associated thrombotic microangiopathies.thrombotic microangiopathies encompass a group of disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia associated with hyaline thrombi (comprised primarily of platelet aggregates in the microcirculation), and varying degrees of end-organ failure. many primary (genetic) and secondary etiological predisposing factors have been described-namely pregnancy, autoimmune disorders, cancer, drugs and antineoplastic therapy, bone marrow transplantation/solid organ transplantation ...201121727765
acquired antibiotic resistance: are we born with it?the rapid emergence of antibiotic resistance (ar) is a major public health concern. recent findings on the prevalence of foodborne antibiotic resistant (art) commensal bacteria in ready-to-consume food products suggested that daily food consumption likely serves as a major avenue for disseminating art bacteria from the food chain to the human hosts. to properly assess the impact of various factors including the food chain on ar development in hosts, it is important to determine the baseline of a ...201121821748
single nucleotide polymorphism (snp)-based differentiation of shigella isolates by pyrosequencing.analysis of single nucleotide polymorphisms (snps) is an important genetic tool that provides molecular markers for rapid differentiation of closely related strains. we have applied snp discovery and analysis for distinguishing each of the four shigella serogroups (boydii, dysenteriae, flexneri, and sonnei) and for discriminating individual strains within the same serogroup by using 24 snps selected from nine genes. five snps were identified from sequence analysis of two housekeeping genes (gapa ...201121839856
outer membrane protein a (ompa) of shigella flexneri 2a, induces protective immune response in a mouse model.in our earlier studies 34 kda outer membrane protein (omp) of shigella flexneri 2a has been identified as an efficient immunostimulant.201121818362
studies on the activity of cyperus rotundus linn. tubers against infectious diarrhea.to study the antidiarrheal activity of the decoction of cyperus rotundus linn. tubers using representative assays of diarrheal pathogenesis and understand its mechanism of action.antibacterial, antigiardial and antirotaviral activities were studied. effect on adherence of enteropathogenic escherichia coli (epec) and invasion of enteroinvasive e. coli (eiec) and shigella flexneri to hep-2 cells was evaluated as a measure of effect on colonization. effect on enterotoxins such as enterotoxigenic e. ...201121713044
epidemiology of food-borne disease outbreaks in the french armed forces: a review of investigations conducted from 1999 to 2009.objective: aim of this study was to describe the main characteristics of food-borne disease outbreaks (fbdos) in the french armed forces from 1999 to 2009. methods: fbdos are reported to the military epidemiological surveillance system, which concerns all active military personnel. investigation reports published from 1999 to 2009 were reviewed. results: among the 180 fbdos reported, 48.3% occurred overseas. the mean reporting rate was 2.4 outbreaks p.100,000 in france and 26.7 p.100,000 oversea ...201121840337
recovery and characterization of environmental variants of shigella flexneri from surface water in bangladesh.little is known about the distribution, survival, and transmission of shigella in environmental surface waters. to gain more insight into the environmental biology of shigella we isolated five bacterial strains serotyped as shigella flexneri 2b from a freshwater lake in bangladesh using a modified nutrient broth supplemented with nucleic acid bases. the biochemical properties of the isolates, including inability to ferment lactose and a negative lysine decarboxylase test, indicated common physio ...201121826486
antimicrobial activity of gynostemma pentaphyllum extracts against fungi producing aflatoxin and fumonisin and bacteria causing diarrheal disease.gynostemma pentaphyllum was investigated to determine its antimicrobial activities against human.and animal pathogens that produce aflatoxin, fumonisin, and diarrheal disease. the fungi were aspergillusflavus, aspergillus parasiticus and fusarium verticillioides. the bacteria were vibrio, salmonella, shigella, escherichia coli and staphylococcus aureus. g. pentaphyllum was extracted by five different methods. the obtained extracts were designated extracts a, b, c, d and e. the results of the ant ...201121706950
a new class of 2-(4-cyanophenyl amino)-4-(6-bromo-4-quinolinyloxy)-6-piperazinyl (piperidinyl)-1,3,5-triazine analogues with antimicrobial/antimycobacterial activity.this study presents the synthesis and in vitro pharmacological evaluations of novel 2-(4-cyanophenyl amino)-4-(6-bromo-4-quinolinyloxy)-6-piperazinyl (piperidinyl)-1,3,5-triazines. the title compounds were assayed for their in vitro antimicrobial activity against eight bacteria (staphylococcus aureus, bacillus cereus, escherichia coli, pseudomonas aeruginosa, klebsiella pneumoniae, salmonella typhi, proteus vulgaris, shigella flexneria) and four fungi (aspergillus niger, aspergillus fumigatus, a ...201121740100
multi-pathogen waterborne disease outbreak associated with a dinner cruise on lake michigan.summarywe report an outbreak associated with a dinner cruise on lake michigan. this took place on the same day as heavy rainfall, which resulted in 42-à4 billion liters of rainwater and storm runoff containing highly diluted sewage being released into the lake. of 72 cruise participants, 41 (57%) reported gastroenteritis. stool specimens were positive for shigella sonnei (n=3), giardia (n=3), and cryptosporidium (n=2). ice consumption was associated with illness (risk ratio 2-à2, p=0-à011). s. s ...201121676362
structural and functional studies on the n-terminal domain of the shigella type iii secretion protein mxig.mxig is a single-pass membrane protein that oligomerizes within the inner membrane ring of the shigella flexneri type iii secretion system (t3ss). the mxig n-terminal domain (mxig-n) is the predominant cytoplasmic structure; however, its role in t3ss assembly and secretion is largely uncharacterized. we have determined the solution structure of mxig-n residues 6-112 (mxig-n(6-112)), representing the first published structure of this t3ss domain. the structure shows strong structural homology to ...201121733840
physicochemical and microbiological assessment of recreational and drinking waters.the present study was aimed to make an assessment of health risk due to pollution and human pathogenic bacteria associated with the recreational and drinking water sources in twin densely populated holy indian cities ayodhya and faizabad. though physicochemical studies revealed that the water available in the area is under recommended limits for human use, it is unsafe on account of poor microbiological quality of surface and ground water in the region. the most probable number (mpn) test result ...201121713494
a multi-center randomized trial to assess the efficacy of gatifloxacin versus ciprofloxacin for the treatment of shigellosis in vietnamese children.the bacterial genus shigella is the leading cause of dysentery. there have been significant increases in the proportion of shigella isolated that demonstrate resistance to nalidixic acid. while nalidixic acid is no longer considered as a therapeutic agent for shigellosis, the fluoroquinolone ciprofloxacin is the current recommendation of the world health organization. resistance to nalidixic acid is a marker of reduced susceptibility to older generation fluoroquinolones, such as ciprofloxacin. w ...201121829747
a multifactor regulatory circuit involving h-ns, virf and an antisense rna modulates transcription of the virulence gene icsa of shigella flexneri.the icsa gene of shigella encodes a structural protein involved in colonization of the intestinal mucosa by bacteria. this gene is expressed upon invasion of the host and is controlled by a complex regulatory circuit involving the nucleoid protein h-ns, the arac-like transcriptional activator virf, and a 450ôçënt antisense rna (rnag) acting as transcriptional attenuator. we investigated on the interplay of these factors at the molecular level. dnase i footprints reveal that both h-ns and virf bi ...201121724612
the rickettsia surface cell antigen 4 applies mimicry to bind to and activate vinculin.pathogenic rickettsiae species cause high morbidity and mortality, especially r. prowazekii the causative agent of typhus. like many intracellular pathogens, rickettsiae exploit the cytoskeleton to enter and spread within the host cell. here we report that the cell surface antigen sca4 of rickettsiae colocalizes with vinculin in cells at sites of focal adhesions, and that sca4 binds to and activates vinculin through two vinculin binding sites (vbss) that are conserved across all rickettsia. rema ...201121841197
epidemiology and molecular mechanism of integron-mediated antibiotic resistance in shigella.integrons are gene capture and expression systems that are characterized by the presence of an integrase gene. this encodes an integrase, a recombined site, and a promoter. they are able to capture gene cassettes from the environment and incorporate them using site-specific recombination. the role of integrons and gene cassettes in the dissemination of multidrug resistance in gram-negative bacteria is significant. in shigella species, antimicrobial resistance is often associated with the presenc ...201121842348
antibacterial dimeric copper(ii) complexes with chromone-derived compounds.a new series of six chromone-derived compounds and their cu(ii) complexes have been synthesized and characterized by their physical, spectral and analytical data. the ligands and their cu(ii) complexes were screened for their in vitro antibacterial activity against four gram-negative (escherichia coli, pseudomonas aeruginosa, salmonella typhi, shigella flexneri) and two gram-positive (bacillus subtilis, staphylococcus aureus) bacterial strains by agar-well diffusion method. the ligands were foun ...201121699463
espg of enteropathogenic and enterohemorrhagic e. coli binds the golgi matrix protein gm130 and disrupts the golgi structure and function.the enteric pathogens enteropathogenic escherichia coli (epec), enterohaemorrhagic e. coli (ehec) and shigella flexneri all translocate at least one effector protein of the espg protein family into host cells via a type iii secretion system (t3ss). the espg family comprises espg, espg2 and vira. from a y2h screen, we identified the golgi matrix protein gm130 as a potential binding partner of espg. we confirmed espg:gm130 protein interaction by affinity co-purification. in co-immunoprecipitation ...201121740499
in vivo versus in vitro protein abundance analysis of shigella dysenteriae type 1 reveals changes in the expression of proteins involved in virulence, stress and energy metabolism.shigella dysenteriae serotype 1 (sd1) causes the most severe form of epidemic bacillary dysentery. quantitative proteome profiling of shigella dysenteriae serotype 1 (sd1) in vitro (derived from lb cell cultures) and in vivo (derived from gnotobiotic piglets) was performed by 2d-lc-ms/ms and apex, a label-free computationally modified spectral counting methodology.201121702961
the yersinia enterocolitica type 3 secretion system (t3ss) as toolbox for studying the cell biological effects of bacterial rho gtpase modulating t3ss effector proteins.the bacterial effector proteins ipgb(1) and ipgb(2) of shigella and map of escherichia coli activate the rho gtpases rac1, rhoa and cdc42, respectively, whereas yope and yopt of yersinia inhibit these rho family gtpases. we established a yersinia toolbox which allows to study the cellular effects of these effectors in different combinations in the context of yersinia type 3 secretion system (ysc)-t3ss-mediated injection into hela cells. for this purpose hybrid proteins were constructed by fusion ...201121718421
investigating the global genomic diversity of escherichia coli using a multi-genome dna microarray platform with novel gene prediction strategies.abstract:201121733163
epidemiology and outcome of shigella, salmonella and campylobacter infections in travellers returning from the tropics with fever and diarrhoea.during a study on fever after a stay in the tropics, we aimed at investigating the epidemiology and outcome of invasive bacterial enteritis due to shigella, salmonella or campylobacter spp. in patients diagnosed with febrile traveller's diarrhoea.201121837926
differential response of the human renal proximal tubular epithelial cell line hk-2 to shiga toxin types 1 and 2.shiga toxins (stxs) are expressed by the enteric pathogens shigella dysenteriae serotype 1 and certain serotypes of escherichia coli. stx-producing bacteria cause bloody diarrhea with the potential to progress to acute renal failure. stxs are potent protein synthesis inhibitors and are the primary virulence factors responsible for renal damage that may follow diarrheal disease. we explored the use of the immortalized human proximal tubule epithelial cell line hk-2 as an in vitro model of stx-ind ...201121708996
atomic structure of bacteriophage sf6 tail needle knob.podoviridae are double-stranded dna bacteriophages that use short, non-contractile tails to adsorb to the host cell surface. within the tail apparatus of p22-like phages, a dedicated fiber known as the "tail needle" likely functions as a cell envelope-penetrating device to promote ejection of viral dna inside the host. in sf6, a p22-like phage that infects shigella flexneri, the tail needle presents a c-terminal globular knob. this knob, absent in phage p22 but shared in other members of the p22 ...201121705802
whole-genome phylogeny of escherichia coli/shigella group by feature frequency profiles (ffps).a whole-genome phylogeny of the escherichia coli/shigella group was constructed by using the feature frequency profile (ffp) method. this alignment-free approach uses the frequencies of l-mer features of whole genomes to infer phylogenic distances. we present two phylogenies that accentuate different aspects of e. coli/shigella genomic evolution: (i) one based on the compositions of all possible features of length l = 24 (∼8.4 million features), which are likely to reveal the phenetic grouping a ...201121536867
rapid situation & response assessment of diarrhoea outbreak in a coastal district following tropical cyclone aila in india.background & objectives : cyclone aila hit indian states on eastern coast on may 25, 2009. an investigation was conducted to examine if aila was responsible for increased reporting of diarrhoea cases from the district of east-medinipur in west bengal. identifying causative organisms for diarrhoea and assessing their antibiotic susceptibility profile were other objectives. methods: rapid situation and response assessment technique was employed to triangulate primary and secondary data collected t ...201121537092
toxic megacolon from sexually transmitted shigella sonnei infection. 201121538050
development of a new guinea-pig model of shigellosis.shigellosis is a major form of bacillary dysentery caused by shigella spp. to date, there is no suitable animal model to evaluate the protective efficacy of vaccine candidates against this pathogen. here, we describe a successful experimental shigellosis in the guinea-pig model, which has shown the characteristic features of human shigellosis. this model yielded reproducible results without any preparatory treatment besides cecal ligation. in this study, guinea-pigs were discretely infected with ...201121539623
effects of probiotic fermentation on the enhancement of biological and pharmacological activities of codonopsis lanceolata extracted by high pressure treatment.this study was designed to evaluate the enhancement of antioxidant, antimicrobial, enzymatic, cytotoxic, and cognitive activities of codonopsis lanceolata extracted by high pressure treatment followed by probiotic fermentation. dried c. lanceolata samples were subjected to 400mpa for 20min and then fermented with bifidobacterium longum b6 (hpe-blf) and lactobacillus rhamnosus (hpe-lrf) at 37°c for 7days. compared to conventional extraction (ce-nf, 6.69mg gae/g), the phenol amounts of hpe-blf and ...201121543255
evaluation of the selective and differential et medium for detection of edwardsiella tarda in aquaculture systems.aims:  edwardsiella tarda is an important pathogen in aquaculture where it can cause serious losses. a rapid detection of it is vital to minimize the mortalities caused by this disease, and in this work, the effectiveness of the selective differential edw. tarda medium (et) was evaluated for the diagnosis of edwardsiellosis as well as for its possible use in epidemiological studies. methods and results:  et medium was evaluated in parallel with the commercial salmonella-shigella agar (ss), which ...201121554344
human immunodeficiency virus-associated gastrointestinal disease: common endoscopic biopsy diagnoses.the gastrointestinal (gi) tract is a major site of disease in hiv infection: almost half of hiv-infected patients present with gi symptoms, and almost all patients develop gi complications. gi symptoms such as anorexia, weight loss, dysphagia, odynophagia, abdominal pain, and diarrhea are frequent and usually nonspecific among these patients. endoscopy is the diagnostic test of choice for most hiv-associated gi diseases, as endoscopic and histopathologic evaluation can render diagnoses in patien ...201121559197
food-specific attribution of selected gastrointestinal illnesses: estimates from a canadian expert elicitation survey.abstract the study used a structured expert elicitation survey to derive estimates of food-specific attribution for nine illnesses caused by enteric pathogens in canada. it was based on a similar survey conducted in the united states and focused on campylobacter spp., escherichia coli o157:h7, listeria monocytogenes, nontyphoidal salmonella enterica, shigella spp., vibrio spp., yersinia enterocolitica, cryptosporidium parvum, and norwalk-like virus. a snowball approach was used to identify food ...201121561379
the decoupling between genetic structure and metabolic phenotypes in escherichia coli leads to continuous phenotypic diversity.to assess the extent of intra-species diversity and the links between phylogeny, lifestyle (habitat and pathogenicity) and phenotype, we assayed the growth yield on 95 carbon sources of 168 escherichia strains. we also correlated the growth capacities of 14 e. coli strains with the presence/absence of enzyme-coding genes. globally, we found that the genetic distance, based on multilocus sequence typing data, was a weak indicator of the metabolic phenotypic distance. besides, lifestyle and phylog ...201121569155
a tecpr1-dependent selective autophagy pathway targets bacterial pathogens.selective autophagy of bacterial pathogens represents a host innate immune mechanism. selective autophagy has been characterized on the basis of distinct cargo receptors but the mechanisms by which different cargo receptors are targeted for autophagic degradation remain unclear. in this study we identified a highly conserved tectonin domain-containing protein, tecpr1, as an atg5 binding partner that colocalized with atg5 at shigella-containing phagophores. tecpr1 activity is necessary for effici ...201121575909
a shigella boydii bacteriophage which resembles salmonella phage vii.abstract: background: lytic bacteriophages have been applied successfully to control the growth of various foodborne pathogens. sequencing of their genomes is considered as an important preliminary step to ensure their safety prior to food applications. results: the lytic bacteriophage, phisbom-ag3, targets the important foodborne pathogen, shigella. it is morphologically similar to phage vii of salmonella enterica serovar typhi and a series of phages of acinetobacter calcoaceticus and rhizobium ...201121595934
shigella sonnei vaccine candidates wrss2 and wrss3 are as immunogenic as wrss1, a clinically tested vaccine candidate, in a primate model of infection.shigella causes diarrhea and dysentery through contaminated food and water. shigella sonnei live vaccine candidates wrss2 and wrss3 are attenuated principally by the loss of virg(icsa) that prevents bacterial spread within the colonic epithelium. in this respect they are similar to the clinically tested vaccine candidate wrss1. however, wrss2 and wrss3 are further attenuated by loss of sena, senb and wrss3 also lacks msbb2. as previously shown in cell culture assays and in small animal models, t ...201121596086
transient suppression of shigella flexneri type 3 secretion by a protective o-antigen-specific monoclonal iga.abstract mucosal immunity to the enteric pathogen shigella flexneri is mediated by secretory iga (s-iga) antibodies directed against the o-antigen (o-ag) side chain of lipopolysaccharide. while secretory antibodies against the o-ag are known to prevent bacterial invasion of the intestinal epithelium, the mechanisms by which this occurs are not fully understood. in this study, we report that the binding of a murine monoclonal iga (igac5) to the o-ag of s. flexneri serotype 5a suppresses activity ...201121610121
dynamic aspects of antibody:oligosaccharide complexes characterized by molecular dynamics simulations and std-nmr.carbohydrates are likely to maintain significant conformational flexibility in antibody:carbohydrate complexes. as demonstrated herein for the protective monoclonal antibody f22-4 recognizing the shigella flexneri 2a o-antigen and numerous synthetic oligosaccharide fragments thereof, the combination of molecular dynamics simulations and nmr saturation transfer difference experiments, supported by physicochemical analysis, allows to determine the binding epitope and its various contributions to a ...201121610193
identification of small-molecule inhibitors of yersinia pestis type iii secretion system yscn atpase.yersinia pestis is a gram negative zoonotic pathogen responsible for causing bubonic and pneumonic plague in humans. the pathogen uses a type iii secretion system (t3ss) to deliver virulence factors directly from bacterium into host mammalian cells. the system contains a single atpase, yscn, necessary for delivery of virulence factors. in this work, we show that deletion of the catalytic domain of the yscn gene in y. pestis co92 attenuated the strain over three million-fold in the swiss-webster ...201121611119
bacterial load of fresh vegetables and their resistance to the currently used antibiotics in saudi arabia.abstract this study was carried out to describe the bacterial load and the occurrence of some disease-causing enteric bacteria on raw vegetables sold in saudi markets. the study further aimed to analyze antibiotic resistance rates, production of extended-spectrum beta lactamase, and plasmid carriage among bacterial population of raw vegetables. results revealed that none of them contained bacillus cereus, salmonella, and escherichia coli o157:h7. however, staphylococcus aureus and shigella were ...201121612423
a novel compound from the marine bacterium bacillus pumilus s6-15 inhibits biofilm formation in gram-positive and gram-negative species.biofilm formation is a critical problem in nosocomial infections and in the aquaculture industries and biofilms show high resistance to antibiotics. the aim of the present study was to reveal a novel anti-biofilm compound from marine bacteria against antibiotic resistant gram-positive and gram-negative biofilms. the bacterial extract (50 μg ml(-1)) of s6-01 (bacillus indicus = mtcc 5559) showed 80-90% biofilm inhibition against escherichia coli, shigella flexneri, proteus mirabilis and s6-15 (ba ...201121614700
prevalence of the plasmid mediated quinolone resistance determinants among clinical isolates of shigella sp. in andaman & nicobar islands, india.aims:  the present study was carried out to find the prevalence of various plasmid mediated quinolone resistant (pmqr) determinants among the quinolone resistant clinical isolates of shigella sp. from pediatric patients in andaman & nicobar islands. methods and results:  a total of 106 quinolone resistant shigella isolates obtained from pediatric patients during hospital based surveillance from january 2003 to june 2010 were screened for the presence of various pmqr determinants. out of 106 isol ...201121615433
complete (1)h and (13)c nmr chemical shift assignments of mono-, di-, and trisaccharides as basis for nmr chemical shift predictions of polysaccharides using the computer program casper.the computer program casper uses (1)h and (13)c nmr chemical shift data of mono- to trisaccharides for the prediction of chemical shifts of oligo- and polysaccharides. in order to improve the quality of these predictions the (1)h and (13)c, as well as (31)p when applicable, nmr chemical shifts of 30 mono-, di-, and trisaccharides were assigned. the reducing sugars gave two distinct sets of nmr resonances due to the α- and β-anomeric forms. in total 35 (1)h and (13)c nmr chemical shift data sets ...201121621752
fabrication of silver nanoparticles doped in the zeolite framework and antibacterial activity.using the chemical reduction method, silver nanoparticles (ag nps) were effectively synthesized into the zeolite framework in the absence of any heat treatment. zeolite, silver nitrate, and sodium borohydride were used as an inorganic solid support, a silver precursor, and a chemical reduction agent, respectively. silver ions were introduced into the porous zeolite lattice by an ion-exchange path. after the reduction process, ag nps formed in the zeolite framework, with a mean diameter of about ...201121383858
antigen-specific iga b memory cell responses to shigella antigens elicited in volunteers immunized with live attenuated shigella flexneri 2a oral vaccine candidates.we studied the induction of antigen-specific iga memory b cells (b(m)) in volunteers who received live attenuated shigella flexneri 2a vaccines. subjects ingested a single oral dose of 10(7), 10(8) or 10(9) cfu of s. flexneri 2a with deletions in guaba (cvd 1204) or in guaba, set and sen (cvd 1208). antigen-specific serum and stool antibody responses to lps and ipa b were measured on days 0, 7, 14, 28 and 42. iga b(m) cells specific to lps, ipa b and total iga were assessed on days 0 and 28. we ...201121388888
postinfective bile acid malabsorption: is this a long-term condition?postinfective bile acid malabsorption comprises a group of patients with a history of an episode of acute gastroenteritis triggering chronic diarrhoea. we identified these patients retrospectively from our medical records and assessed their long-term clinical course.201121389860
a candidate approach implicates the secreted salmonella effector protein spvb in p-body disassembly.p-bodies are dynamic aggregates of rna and proteins involved in several post-transcriptional regulation processes. p-bodies have been shown to play important roles in regulating viral infection, whereas their interplay with bacterial pathogens, specifically intracellular bacteria that extensively manipulate host cell pathways, remains unknown. here, we report that salmonella infection induces p-body disassembly in a cell type-specific manner, and independently of previously characterized pathway ...201121390246
structural elucidation of the o-antigen of the shigella flexneri provisional serotype 88-893: structural and serological similarities with s. flexneri provisional serotype y394 (1c).the structure of the repeating unit of the o-antigen polysaccharide from shigella flexneri provisional serotype 88-893 has been determined. (1)h and (13)c nmr spectroscopy as well as 2d nmr experiments were employed to elucidate the structure. the carbohydrate part of the hexasaccharide repeating unit is identical to the previously elucidated structure of the o-polysaccharide from s. flexneri prov. serotype y394. the o-antigen of s. flexneri prov. serotype 88-893 carries 0.7 mol o-acetyl group p ...201121392735
shigella flexneri type iii secreted effector ospf reveals new crosstalks of proinflammatory signaling pathways during bacterial infection.shigella flexneri type iii secreted effector ospf harbors a phosphothreonine lyase activity that irreversibly dephosphorylates map kinases (mapks) p38 and erk in infected epithelial cells and thereby, dampens innate immunity. whereas this activity has been well characterized, the impact of ospf on other host signaling pathways that control inflammation was unknown. here we report that ospf potentiates the activation of the mapk jnk and the transcription factor nf-?b during s. flexneri infection. ...201121402152
etiology of diarrhea in young children and patterns of antibiotic resistance in cambodia.little is known about diarrhea etiology and antibiotic resistance in developing countries where diarrhea is a major public health problem.201121412204
new insights into vinculin function and regulation.vinculin is a cytoplasmic actin-binding protein enriched in focal adhesions and adherens junctions that is essential for embryonic development. much is now known regarding the role of vinculin in governing cell-matrix adhesion. in the past decade that the crystal structure of vinculin and the molecular details for how vinculin regulates adhesion events have emerged. the recent data suggests a critical function for vinculin in regulating integrin clustering, force generation, and strength of adhe ...201121414589
antibacterial activity of the enniatin b, produced by fusarium tricinctum in liquid culture, and cytotoxic effects on caco-2 cells.the enniatins (ens) are bioactive compounds of hexadepsipeptidic structure produced by several strains of fusarium sp. the en b was purified from extracts of fusarium tricinctum growth on liquid culture of potato dextrose broth (pdb), using a semipreparative liquid chromatography (lc) followed by an analytical lc. the purity and the structure of the isolated compound were confirmed by the determination of the extinction coefficient and with electrospray ionization-mass spectrometry (esi-ms) stud ...201121417626
synthesis and in vitro microbiological evaluation of novel diethyl 6,6'-(1,4-phenylene)bis(4-aryl-2-oxo-cyclohex-3-enecarboxylates).novel bis cyclohexenone ester derivatives 14-19 were synthesized and characterized by their spectral data. in vitro microbiological evaluations were carried out for all the novel compounds 14-19 against clinically isolated bacterial and fungal strains. compounds 15, 16, 18 against staphylococcus aureus, 14, 15 against ß-haemolytic streptococcus, 15, 19 against micrococcus luteus, 17, 18 against salmonella typhii, 14, 17 against shigella flexneri, 15 against escherichia coli, 16 against pseudomon ...201121417963
evaluation of antidiarrheal and in vitro antiprotozoal activities of extracts of leaves of alocasia indica.alocasia indica schott (araceae) is used in several regions of india, especially in rural communities, by traditional medicine practitioners to treat diarrhea. however, no scientific data are available to justify the traditional potentials of the plant species in gastrointestinal disorders.201121428863
Natural Products Modulate Shigella-Host Cell Interaction.This study focussed on identifying possible new options derived from natural sources for the treatment of bacterial infections. Several natural products were investigated for their potential in modulating Shigella-host cell interaction. The proliferation of Shigella sonnei was effectively inhibited inside HEp-2 cells in the presence of 4-methoxycinnamic acid and propolin D. Propolin D also significantly reduced the apopotosis of infected macrophage-like U937 cells, and moderately reduced the sec ...201121719574
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
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
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
chemical and antidiarrheal studies of plinia cauliflora.plinia cauliflora (mart.) kausel, widespread in south america, has edible fruits, and its bark is commonly used against diarrhea and other disorders, on account of its astringency. because diarrhea is still one of the most important causes of illness and death among children in developing countries, where the population turns to traditional medicine for its treatment, the present study determined the composition of fruit and leaf extracts of p. cauliflora, analyzed the activity against diarrhea ...201121861716
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
Differentiation between Shigella, enteroinvasive Escherichia coli (EIEC) and noninvasive Escherichia coli.Shigella causes bacillary dysentery and is classified into four species based on their antigen characteristics. This classification does not reflect genetic relatedness; in fact, Shigella species are so related to Escherichia coli , they should be classified as one distinctive species in the genus Escherichia. The differentiation of Shigella and E. coli is even more complicated with the description of enteroinvasive E. coli (EIEC). EIEC are strains that possess some of the biochemical characteri ...201121901636
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
[Investigation of verotoxigenic escherichia coli O157:H7 incidence in gastroenteritis patients].Escherichia coli O157:H7 is the most common serotype among verotoxigenic E.coli (VTEC) strains that cause haemolytic uremic syndrome. Although sporadic VTEC cases originating from Turkey and small outbreaks have been reported from our country, VTEC has not been routinely investigated in most of the diagnostic microbiology laboratories in Turkey and studies related to this topic are limited. In this study, the incidence of E.coli O157:H7 in patients who were admitted to Alanya Research and Applic ...201121935785
Mucosal immunization with Shigella flexneri outer membrane vesicles induced protection in mice.Vaccination appears to be the only rational prophylactic approach to control shigellosis. Unfortunately, there is still no safe and efficacious vaccine available. We investigated the protection conferred by a new vaccine containing outer membrane vesicles (OMVs) from Shigella flexneri with an adjuvant based on nanoparticles in an experimental model of shigellosis in mice. OMVs were encapsulated in poly(anhydride) nanoparticles prepared by a solvent displacement method with the copolymer PMV/MA. ...201121911022
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
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
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
antimicrobial and toxicological activities of five medicinal plant species from cameroon traditional medicine.infectious diseases caused by multiresistant microbial strains are on the increase. fighting these diseases with natural products may be more efficacious. the aim of this study was to investigate the in vitro antimicrobial activity of methanolic, ethylacetate (etoac) and hexanic fractions of five cameroonian medicinal plants (piptadeniastum africana, cissus aralioides, hileria latifolia, phyllanthus muellerianus and gladiolus gregasius) against 10 pathogenic microorganisms of the urogenital and ...201121867554
microbiological quality of drinking water from dispensers in roadside restaurants of bangladesh.the microbiological status of water from dispensers in different roadside restaurants of dhaka city and savar area was analyzed in this study. seven samples from dhaka and 8 samples of savar were checked. the heterotrophic plate count was in a range of 1.0 x 10(3) cfu ml(-1) to 2.0 x 10(4) cfu ml(-1) (from new bottles), 1.0 x 10(3) to 1.5 x 10(4) cfu ml(-1) (after dispensation), and 1.5 x 10(3) cfu ml(-1) to 1.0 x l0(5) cfu ml(-1) (from serving glass). in several of the samples, the heterotrophi ...201121916267
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
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
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
the effect of the potential phoq histidine kinase inhibitors on shigella flexneri virulence.phoq/phop is an important two-component system that regulates shigella virulence. we explored whether the phoq/phop system is a promising target for new antibiotics against s. flexneri infection. by using a high-throughput screen and enzymatic activity coupled assay, four compounds were found as potential phoq inhibitors. these compounds not only inhibited the activity of sf-phoqc autophosphorylation but also displayed high binding affinities to the sf-phoqc protein in the surface plasmon resona ...201121853073
crosslinking of (cytosine-5)-dna methyltransferase ssoii and its complexes with specific dna duplexes provides an insight into their structures.(cytosine-5)-dna methyltransferase ssoii (m.ssoii) functions as a methyltransferase and also as a transcription factor. chemical and photochemical crosslinking was used for exploring the structure of m.ssoii-dna complexes and m.ssoii in the absence of dna. photocrosslinking with 4-(n-maleimido)benzophenone demonstrated that in the m.ssoii complex with dna containing the regulatory site, the m.ssoii region responsible for methylation was bound to dna flanking the regulatory site, which contained ...201121888553
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
real-time multiplex pcr for simultaneous detection of campylobacter jejuni, salmonella, shigella and yersinia species in fecal samples.diarrheal diseases due to notifiable bacterial infections require rapid diagnosis of the causative pathogens. to facilitate detection, a real-time multiplex pcr was developed that identifies common diarrhea-causing bacteria in fecal samples. on the basis of published sequence data, sets of primers and probes were designed that were specific for campylobacter jejuni, salmonella, shigella/enteroinvasive escherichia coli eiec, and yersinia species, suitable for use in a one-tube pcr assay. the assa ...201121855409
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
intestinal parasitosis and shigellosis among diarrheal patients in gondar teaching hospital, northwest ethiopia.abstract:201122041102
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
waterlogsy nmr experiments in conjunction with molecular-dynamics simulations identify immobilized water molecules that bridge peptide mimic mdwnmhaa to anticarbohydrate antibody sya/j6.x-ray crystallographic data of the carbohydrate mimic mdwnmhaa when bound to an anti-shigella flexneri y mab sya/j6 indicate the immobilization of water molecules, that is, the presence of "bound" waters, in the active site. water ligand observed via gradient spectroscopy (waterlogsy) was used in conjunction with saturation transfer difference (std)-nmr spectroscopy to probe the existence of immobilized water molecules in the complex of mdwnmhaa 1 bound to mab sya/j6. molecular dynamics simulati ...201121887835
[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
matrix-assisted laser desorption ionization-time of flight mass spectrometry for the identification of bacteria and yeasts in a clinical microbiological laboratory: a review.recently, maldi-tof ms devices designed for use in clinical laboratories have been commercially introduced in various large centres worldwide. all published studies conclude that maldi-tof ms can be implemented easily for routine identification of bacteria and yeasts in a clinical microbiological laboratory. although all data show that maldi-tof ms correctly identifies the great majority of isolates processed routinely, it cannot yet identify every such isolate. until today, maldi-tof ms is inap ...201121938981
structural segregation of gut microbiota between colorectal cancer patients and healthy volunteers.despite a long-suspected role in the development of human colorectal cancer (crc), the composition of gut microbiota in crc patients has not been adequately described. in this study, fecal bacterial diversity in crc patients (n=46) and healthy volunteers (n=56) were profiled by 454 pyrosequencing of the v3 region of the 16s ribosomal rna gene. both principal component analysis and unifrac analysis showed structural segregation between the two populations. forty-eight operational taxonomic units ...201121850056
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
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
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
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
Ciprofloxacin-resistant Shigella sonnei among men who have sex with men, Canada, 2010.In 2010, we observed isolates with matching pulsed-field gel electrophoresis patterns from 13 cases of ciprofloxacin-resistant Shigella sonnei in Montréal. We report on the emergence of this resistance type and a study of resistance mechanisms. The investigation suggested local transmission among men who have sex with men associated with sex venues.201121888811
characterization of a vii-like phage specific to escherichia coli o157:h7.phage vb_ecom_cba120 (cba120), isolated against escherichia coli o157:h7 from a cattle feedlot, is morphologically very similar to the classic phage vii of salmonella enterica serovar typhi. until recently, little was known genetically or physiologically about the vii-like phages, and none targeting e. coli have been described in the literature. the genome of cba120 has been fully sequenced and is highly similar to those of both vii and the shigella phage ag3. the core set of structural and repl ...201121899740
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
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
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
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
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
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