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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
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
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
microbiological quality of grey-mullet roe.the greek grey-mullet roe is produced from the fully developed gonads of the female mullet (mugil cephalus) couth in lagoons during their reproductive migration. the traditional processing method of the roe includes, air drying, salting, shape formation and covering with multiple layers of natural beeswax for preservation and distribution. fish roe brands have been a staple in local diet and is increasingly becoming popular in the international market. as a ready-to-eat food it's microbial quali ...201121497664
interaction of the salmonella typhimurium effector protein sopb with host cell cdc42 is involved in intracellular replication.the phosphoinositide phosphatase sopb/sigd is a type iii secretion system effector that plays multiple roles in salmonella internalization and intracellular survival. we previously reported that sopb complexed with and inhibited the small gtpase cdc42 when expressed in a yeast model system, independently of its phosphatase activity. here we show that human cdc42, but not rac1, interacts with catalytically inactive sopb when coexpressed in saccharomyces cerevisiae. this interaction occurs with bo ...201121435037
multi-drug resistance and characteristic of integrons in shigella spp. isolated from china.to investigate the characteristic of integrons and the relationship between integrons and antimicrobial resistance in shigella spp.201121440840
quantification and evaluation of infectivity of shiga toxin-encoding bacteriophages in beef and salad.stx bacteriophages in 68 samples of beef and salad were quantified by real-time quantitative pcr (qpcr). stx phages from the samples were propagated in escherichia coli c600, e. coli o157:h7, and shigella strains and further quantified. fifty percent of the samples carried infectious stx phages that were isolated from plaques generated by lysis.201121441341
antimicrobial susceptibilities of enteric bacterial pathogens isolated in kathmandu, nepal, during 2002-2004.the prevalence and antimicrobial susceptibility patterns of the bacterial enteropathogens vibrio cholerae, salmonella species and shigella species were investigated.201121444984
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
antagonistic bacteria from live corals, tuticorin coastal waters, southeastern india.the objective of this study is to isolate and production of secondary metabolites with bioactive substances by coral reef (acropora formosa and favia palida) associated bacteria was carried out from the tuticorin coastal waters, southeastern india. the isolated coral associated bacteria were found to have an antagonistic effect against 10 human pathogens. the pathogens were escherichia coli, shigella dysentriae, staphylococcus epidermidis, s. aureus, klebsiella pneumoniae, pseudomonas aerogenosa ...201121454167
[invasive gastroenteritis, anything new?].invasive gastroenteritis is characterized by fever and inflammatory diarrhea and can be caused by nontyphoideal salmonella serotypes and shigella spp.-enteroinvasive escherichia coli (eiec), among other pathogens. this review describes emerging monophasic variants of salmonella enterica serotype 1,4,[5],12:i:- and provides an evolutionary consideration of shigella spp.-eiec as a single pathotype. in 1997, a monophasic variant of s. enterica serotype 1,4,[5],12:i:-, phage-type u302, multidrug res ...201121458713
vinculin activators target integrins from within the cell to increase melanoma sensitivity to chemotherapy.metastatic melanoma is an aggressive skin disease for which there are no effective therapies. emerging evidence indicates that melanomas can be sensitized to chemotherapy by increasing integrin function. current integrin therapies work by targeting the extracellular domain, resulting in complete gains or losses of integrin function that lead to mechanism-based toxicities. an attractive alternative approach is to target proteins, such as vinculin, that associate with the integrin cytoplasmic doma ...201121460181
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
zidovudine (azt) has a bactericidal effect on enterobacteria and induces genetic modifications in resistant strains.the spread of multiresistant bacteria increases the need for new antibiotics. the observation that some nucleoside analogues have antibacterial activity led us to further investigate the antimicrobial activity and resistance of zidovudine (azt). we determined the minimum inhibition concentration (mic), studied time-kill curves, induced resistant bacteria and sequenced the gene for thymidine kinase. we demonstrate that azt has a bactericidal effect on some enterobacteria. however, azt could induc ...201121494911
autophagy and the cytoskeleton: new links revealed by intracellular pathogens.actin-based motility is used by various pathogens such as listeria and shigella for dissemination within cells: and tissues, yet host factors counteracting this process have not been identified. we have recently discovered that infected host cells can prevent actin-based motility of shigella by compartmentalizing bacteria inside 'septin cages,' revealing a novel mechanism of host defense that restricts dissemination. because bacterial proteins controlling actin-based motility also regulate the a ...201121464614
antimicrobial activity against shigella sonnei and probiotic properties of wild lactobacilli from fermented food.four lactobacilli strains (lactobacillus paracasei subp. paracasei m5-l, lactobacillus rhamnosus j10-l, lactobacillus casei q8-l and l. rhamnosus gg (lgg), were systematically assessed for the production of antimicrobial substances active towards shigella sonnei, escherichia coli and salmonella typhimurium. agar-well assay showed that the four lactobacilli strains displayed strong antibacterial activity towards s. sonnei. the nature of antimicrobial substances was also investigated and shown to ...201121466951
assessment of the antibacterial activity and the antidiarrheal function of flavonoids from bayberry fruit.chinese bayberry fruits are used as a folk medicine to cure diarrhea. however, the active compounds have not yet been reported. we found that bayberry fruit extract showed significant antibacterial activity against salmonella, listeria, and shigella, and the minimal inhibitory concentration (mic) ranged from 2.07 to 8.28 mg/ml. positive relationships were found between the antibacterial activity and the total polyphenol (r = 0.88) and flavonoid contents (r = 0.92) of samples using different extr ...201121469731
genetic diversity and antibiotic resistance in shigella dysenteriae and shigella boydii strains isolated from children aged <5 years in egypt.summarydiversity within shigella dysenteriae (n=40) and shigella boydii (n=30) isolates from children living in egypt aged <5 years was investigated. shigella-associated diarrhoea occurred mainly in summer months and in children aged <3 years, it commonly presented with vomiting and fever. serotypes 7 (30%), 2 (28%), and 3 (23%) accounted for most of s. dysenteriae isolates; 50% of s. boydii isolates were serotype 2. s. dysenteriae and s. boydii isolates were often resistant to ampicillin, chlor ...201121470441
new developments in traveler's diarrhea.traveler's diarrhea (td) is a crucial area for research, as it affects millions of tourists each year and creates a large economic burden. more than 60% of td cases are caused by a variety of bacterial enteropathogens: diarrhea-producing escherichia coli, shigella, campylobacter, salmonella, aeromonas, plesiomonas, and noncholera vibrios. noroviruses are also an important cause of morbidity among travelers. recent studies have identified host genetic risk factors associated with susceptibility t ...201121475415
behavior of salmonella typhimurium, staphylococcus aureus, listeria monocytogenes, and shigella flexneri and shigella sonnei during production of pulque, a traditional mexican beverage.pulque is a typical fermented alcoholic beverage of central mexico, produced from the nectar of maguey agave plants. production systems are largely artisanal, with inadequate hygiene conditions and exposure to multiple contamination sources. no data exist on pulque microbiological safety and the behavior of pathogenic microorganisms in agave nectar and pulque. an initial trial was done of the behavior of salmonella typhimurium, staphylococcus aureus, listeria monocytogenes, and shigella flexneri ...201121477472
dissemination of ndm-1 positive bacteria in the new delhi environment and its implications for human health: an environmental point prevalence study.not all patients infected with ndm-1-positive bacteria have a history of hospital admission in india, and extended-spectrum β-lactamases are known to be circulating in the indian community. we therefore measured the prevalence of the ndm-1 gene in drinking water and seepage samples in new delhi.201121478057
corn flake-like morphology of iron nanoparticles and its antibacterial property. 201121478648
an integrated approach for finding overlooked genes in shigella.the completion of numerous genome sequences introduced an era of whole-genome study. however, many genes are missed during genome annotation, including small rnas (srnas) and small open reading frames (sorfs). in order to improve genome annotation, we aimed to identify novel srnas and sorfs in shigella, the principal etiologic agents of bacillary dysentery.201121483688
outbreak of shigella sonnei infections in the orthodox jewish community of antwerp, belgium, april to august 2008.in the beginning of april 2008 three cases of shigella sonnei infection were identified among the orthodox jewish community of antwerp, belgium. we conducted a descriptive study and a household cohort study to identify potential risk factors. stool samples were cultured and antibiotic susceptibility of the isolates was determined. between april and august 2008, 42 cases were registered. all characterised isolates (n=20) shared an identical pulsed-field gel electrophoresis profile and were indist ...201121492526
the shigella flexneri type three secretion system effector ipgd inhibits t cell migration by manipulating host phosphoinositide metabolism.shigella, the gram-negative enteroinvasive bacterium that causes shigellosis, relies on its type iii secretion system (ttss) and injected effectors to modulate host cell functions. however, consequences of the interaction between shigella and lymphocytes have not been investigated. we show that shigella invades activated human cd4(+) t lymphocytes. invasion requires a functional ttss and results in inhibition of chemokine-induced t cell migration, an effect mediated by the ttss effector ipgd, a ...201121501826
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
a unique arabinose 5-phosphate isomerase found within a genomic island associated with the uropathogenicity of escherichia coli cft073.previous studies showed that deletion of genes c3405 to c3410 from pai-metv, a genomic island from escherichia coli cft073, results in a strain that fails to compete with wild-type cft073 after a transurethral cochallenge in mice and is deficient in the ability to independently colonize the mouse kidney. our analysis of c3405 to c3410 suggests that these genes constitute an operon with a role in the internalization and utilization of an unknown carbohydrate. this operon is not found in e. coli k ...201121498648
shigella targets t cells.using a syringe-like device, shigella delivers an array of virulence factors into host cells to facilitate bacterial colonization and disable the host's innate immune defense. in this issue of cell host & microbe, konradt and colleagues (konradt et al., 2011) show that shigella also subverts adaptive immunity by targeting t cells through a mechanism involving pip(2) breakdown.201121501822
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
enteric virulence associated protein vapc inhibits translation by cleavage of initiator trna.eukaryotic pin (pilt n-terminal) domain proteins are ribonucleases involved in quality control, metabolism and maturation of mrna and rrna. the majority of prokaryotic pin-domain proteins are encoded by the abundant vapbc toxin-antitoxin loci and inhibit translation by an unknown mechanism. here we show that enteric vapcs are site-specific endonucleases that cleave trna(fmet) in the anticodon stem-loop between nucleotides +38 and +39 in vivo and in vitro. consistently, vapc inhibited translation ...201121502523
evaluation of low-copy genetic targets for waterborne bacterial pathogen detection via qpcr.recent developments in water quality research have highlighted difficulties in accurately predicting the incidence of pathogens within freshwater based on the viability, culturability and metabolic activity of indicator organisms. qpcr-driven assays are candidates to replace standard culture-based methods, however, protocols suitable for routine use have yet to be sufficiently validated. the objective of this study was to evaluate five oligonucleotide primers sets (etir, sinv, exot, vs1 and ipah ...201121514618
functional domains and motifs of bacterial type iii effector proteins and their roles in infection.a key feature of the virulence of many bacterial pathogens is the ability to deliver effector proteins into eukaryotic cells via a dedicated type three secretion system (t3ss). many bacterial pathogens, including species of chlamydia, xanthomonas, pseudomonas, ralstonia, shigella, salmonella, escherichia and yersinia, depend on the t3ss to cause disease. t3ss effectors constitute a large and diverse group of virulence proteins that mimic eukaryotic proteins in structure and function. a salient f ...201121517912
a novel vinculin binding site of the ipaa invasin of shigella.internalization of shigella into host epithelial cells, where the bacteria replicates and spreads to neighboring cells, requires a type 3 secretion system (t3ss) effector coined ipaa. ipaa binds directly to and activates the cytoskeletal protein vinculin after injection in the host cell cytosol and heretofore this was thought to be directed by two amphipathic α-helical vinculin binding sites (vbs) found in the c-terminal tail domain of ipaa. here we report a third vbs, ipaa-vbs3, that is located ...201121525010
synthesis, characterization and biological properties of thienyl derived triazole schiff bases and their oxovanadium(iv) complexes.a new series of biologically active thienyl derived triazole schiff bases and their oxovanadium(iv) complexes have been synthesized and characterized on the basis of physical (m.p., magnetic susceptibility and conductivity), spectral (ir, (1)h and (13)c nmr, electronic and mass spectrometry) and microanalytical data. all the schiff base ligands and their oxovanadium(iv) complexes have been subjected to in vitro antibacterial activity against four gram-negative (escherichia coli, shigella flexner ...201121635212
structure-guided investigation of lipopolysaccharide o-antigen chain length regulators reveals regions critical for modal length control.the o-antigen component of the lipopolysaccharide (lps) represents a population of polysaccharide molecules with a non-random (modal) chain length distribution. the number of the repeat o-units in each individual o-antigen polymer depends on the wzz chain-length regulator, an inner membrane protein belonging to the polysaccharide co-polymerase (pcps) family. different wzz proteins confer vastly different ranges of modal lengths (4 to >100 repeat units) despite having remarkably conserved structu ...201121642455
vital signs: incidence and trends of infection with pathogens transmitted commonly through food--foodborne diseases active surveillance network, 10 u.s. sites, 1996-2010.in the united states, contaminated food causes approximately 1,000 reported disease outbreaks and an estimated 48 million illnesses, 128,000201121659984
p62 and ndp52 target intracytosolic shigella and listeria to different autophagy pathways.autophagy is an important mechanism of innate immune defense. we have recently shown that autophagy components are recruited with septins, a new and increasingly characterized cytoskeleton component, to intracytosolic shigella that have started to polymerize actin. on the other hand, intracytosolic listeria avoids autophagy recognition by expressing acta, a bacterial effector required for actin polymerization. here we exploit shigella and listeria as intracytosolic tools to characterize differen ...201121646350
bacteriophage-encoding cytolethal distending toxin type-v gene induced from non-clinical escherichia coli isolates.cytolethal distending toxin (cdt) is produced by a variety of pathogenic bacteria, including pathogenic serotypes of shiga toxin-producing escherichia coli (stec). the cdt family comprises five variants (cdt-i to cdt-v) encoded by three genes located within the chromosome, plasmids or, in the case of cdt-i, within bacteriophages. in this study we evaluated the occurrence of cdt in a collection of 140 environmental stec isolates. cdt was detected in 12.1% of strains, of which five strains carried ...201121646456
shigella gets captured to gain entry.the type iii secretion system-dependent epithelial invasion and dissemination of shigella is stimulated by atp released through hemichannels. romero et al. (2011) show that prior to epithelial contact, shigella is captured by nanometer-thin micropodial extensions at a distance from the cell surface, in a process involving atp and connexin-mediated signaling.201121669393
development of multiplex loop-mediated isothermal amplification-rflp (mlamp-rflp) to detect salmonella spp. and shigella spp. in milk.a multiplex loop-mediated isothermal amplification-rflp (mlamp-rflp) was developed and validated for simultaneous detection of salmonella strains and shigella strains in milk. in this system, two sets of lamp primers were designed to specifically target inva of salmonella spp. and ipah of shigella spp. under isothermal conditions at 63 °c, ladder pattern of dna bands could be amplified within 60 min in the presence of genomic dnas of salmonella strains and shigella strains, which could be distin ...201121652102
gisul2, a genomic island carrying the sul2 sulphonamide resistance gene and the small mobile element cr2 found in the enterobacter cloacae subspecies cloacae type strain atcc 13047 from 1890, shigella flexneri atcc 700930 from 1954 and acinetobacter baumannii atcc 17978 from 1951. 201121653606
deaths associated with bacterial pathogens transmitted commonly through food: foodborne diseases active surveillance network (foodnet), 1996-2005.foodborne diseases are typically mild and self-limiting but can cause severe illness and death. we describe the epidemiology of deaths associated with bacterial pathogens using data from the foodborne diseases active surveillance network (foodnet) in the united states.201121673037
phenylbutyrate counteracts shigella mediated downregulation of cathelicidin in rabbit lung and intestinal epithelia: a potential therapeutic strategy.cathelicidins and defensins are endogenous antimicrobial peptides (amps) that are downregulated in the mucosal epithelia of the large intestine in shigellosis. oral treatment of shigella infected rabbits with sodium butyrate (nab) reduces clinical severity and counteracts the downregulation of cathelicidin (cap-18) in the large intestinal epithelia.201121673991
analysis of distribution and significance of simple sequence repeats in enteric bacteria shigella dysenteriae sd197.we have explored the possible role of ssr density in genome to generate biological information. in our study, we have checked the ssr (simple sequence repeats) status in virulent and non virulent genes of enteric bacteria to see whether the ssrs distribution contributes to virulence. the genome, plasmid and virulent genes sequences in fasta format were downloaded from ncbi genbank and vfdb. the sequences were subjected to ssr analysis using software tool ssr.exe. the resulting data was pasted in ...201121814393
the future is cold: cryo-preparation methods for transmission electron microscopy of cells.our knowledge of the organization of the cell is linked, to a great extent, to light and electron microscopy. choosing either photons or electrons for imaging has many consequences on the image obtained, as well as on the experiment required in order to generate the image. one apparent effect on the experimental side is in the sample preparation, which can be quite elaborate for electron microscopy. in recent years, rapid freezing, cryo-preparation and cryo-electron microscopy have been more wid ...201121812762
a live noninvasive shigella dysenteriae 1 strain induces homologous protective immunity in a guinea pig colitis model.a noninvasive live transconjugant shigella hybrid (ltsh?stx) strain was constructed from a shiga toxin gene deleted mutant of shigella dysenteriae 1 by introducing a plasmid vector ppr1347 that carried a lipopolysaccharide biosynthesis gene (rfb and rfc) of salmonella typhimurium. in guinea pigs, four successive oral administrations of ltsh?stx showed complete protection against rectal challenge with wild type s. dysenteriae 1 strain. exponential increase of the serum igg and iga titer against l ...201121806676
regulating iron storage and metabolism with rna: an overview of posttranscriptional controls of intracellular iron homeostasis.iron (fe) is a double-edged sword for most living organisms. although it is essential for the catalytic activity of a large number of enzymes, ferrous iron (fe(2+) ) becomes cytotoxic in the presence of normal respiratory by-products such as h(2) o(2) . because of this toxicity, intracellular iron concentrations ought to be regulated by elaborated homeostasis systems that, despite decades of extensive studies, have not yet revealed all of their surprising arrays of mechanistic details. within th ...201121793218
[waterborne outbreak of shigella sonnei caused by consumption of public supply water.]objective: to investigate a waterborne outbreak in the population of valència d'àneu (lleida, spain). methods: a cohort study of consumption of mains water, bottled water and spring water was carried out. the sample was obtained by telephone contact with all private numbers in the municipality. we surveyed 58.3% of the population census (105/180) for water consumption, number of glasses drunk daily and symptoms. the water supply in the municipal system was sampled, and the presence of enterobact ...201121802793
the role of tecpr1 in selective autophagy as a cargo receptor.bacterial intrusion of host cells can be recognized by the innate immune system, including autophagy, via multiple cellular pathways. we have identified tecpr1 as an atg5-binding partner, and found that tecpr1 interacts with the atg12-atg5-atg16l1 complex via binding to atg5. in shigella infected cells, tecpr1 colocalizes with atg5 and lc3 at shigella-containing phagophores. tecpr1 activity is required for efficient autophagy to target bacteria, but a deficiency of tecpr1 in host cells does not ...201121795850
multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance.clin microbiol infect abstract: many different definitions for multidrug-resistant (mdr), extensively drug-resistant (xdr) and pandrug-resistant (pdr) bacteria are being used in the medical literature to characterize the different patterns of resistance found in healthcare-associated, antimicrobial-resistant bacteria. a group of international experts came together through a joint initiative by the european centre for disease prevention and control (ecdc) and the centers for disease control and p ...201121793988
atp-mediated erk1/2 activation stimulates bacterial capture by filopodia, which precedes shigella invasion of epithelial cells.shigella, the causative agent of bacillary dysentery in-áhumans, invades epithelial cells, using a type iii secretory system (t3ss) to inject bacterial effectors into host cells and remodel the actin cytoskeleton. atp released through connexin hemichanels on the epithelial membrane stimulates shigella invasion and dissemination in epithelial cells. here, we show that prior to contact with the cell body, shigella is captured by nanometer-thin micropodial extensions (nmes) at a distance from the c ...201121669399
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
safety, and immunogenicity of an intranasal shigella flexneri 2a invaplex 50 vaccine.background: shigella flexneri 2a invaplex 50 is a nasally delivered subunit vaccine consisting of a macromolecular complex composed of lps, ipab, ipac and ipad. the current study examined vaccine safety and immunogenicity across a dose range and the clinical performance of a new intranasal delivery device. methods: volunteers (n=36) were randomized to receive vaccine via the dolphin™ (valois of america, congers, new york) intranasal spray device at one of three doses (240, 480, and 690µg) on day ...201121787825
multi-functional characteristics of the pseudomonas aeruginosa type iii needle-tip protein, pcrv; comparison to orthologs in other gram-negative bacteria.pseudomonas aeruginosa possesses a type iii secretion system (t3ss) to intoxicate host cells and evade innate immunity. this virulence-related machinery consists of a molecular syringe and needle assembled on the bacterial surface, which allows delivery of t3 effector proteins into infected cells. to accomplish a one-step effector translocation, a tip protein is required at the top end of the t3 needle structure. strains lacking expression of the functional tip protein fail to intoxicate host ce ...201121772833
pathogenic bacteria prime the induction of toll-like receptor signalling in human colonic cells by the gal/galnac lectin carbohydrate recognition domain of entamoebahistolytica.in mixed intestinal infections with entamoeba histolytica trophozoites and enteropathogenic bacteria, which are wide-spread in areas of endemic amebiasis, interaction between the pathogens could be an important factor in the occurrence of invasive disease. it has been reported that exposure of human colonic cells to enteropathogenic bacteria increased trophozoite adherence to the cells and their subsequent damage. we report here that the carbohydrate recognition domain (crd) of the amebic gal/ga ...201121787776
rodz regulates the post-transcriptional processing of the shigella sonnei type iii secretion system.the expression of the type iii secretion system-a main determinant of virulence in shigella-is controlled by regulator cascades virf-inve (virb) and cpxar two-component system. a screen for mutants that restore virulence in the cpxa background led to the isolation of a mutant of rodz, a cytoskeletal protein that maintains the rod-shaped morphology of bacilli. inve is normally repressed at 30 °c because of decreased messenger rna (mrna) stability, but rodz mutants markedly increase inve-mrna stab ...201121779005
anti-enteric bacterial activity and phytochemical analysis of the seed kernel extract of mangifera indica linnaeus against shigella dysenteriae (shiga, corrig.) castellani and chalmers.to evaluate the phytochemical and anti-bacterial efficacy of the seed kernel extract of mangifera indica (m. indica) against the enteropathogen, shigella dysenteriae (s. dysenteriae), isolated from the diarrhoeal stool specimens.201121771473
serine protease autotransporters from shigella flexneri and pathogenic escherichia coli target a broad range of leukocyte glycoproteins.the serine protease autotransporters of enterobacteriaceae (spates) are secreted by pathogenic gram-negative bacteria through the autotransporter pathway. we previously classified spate proteins into two classes: cytotoxic (class 1) and noncytotoxic (class 2). here, we show that pic, a class 2 spate protein produced by shigella flexneri 2a, uropathogenic and enteroaggregative escherichia coli strains, targets a broad range of human leukocyte adhesion proteins. substrate specificity was restricte ...201121768350
antimicrobial resistance pattern of shigella species over five years at a tertiary-care teaching hospital in north india. 201121766566
molecular identification of bacteria by total sequence screening: determining the cause of death in ancient human subjects.research of ancient pathogens in ancient human skeletons has been mainly carried out on the basis of one essential historical or archaeological observation, permitting specific pathogens to be targeted. detection of ancient human pathogens without such evidence is more difficult, since the quantity and quality of ancient dna, as well as the environmental bacteria potentially present in the sample, limit the analyses possible. using human lung tissue and/or teeth samples from burials in eastern s ...201121765907
shigella are versatile mucosal pathogens that circumvent the host innate immune system.the intestinal mucosa is equipped with multiple innate immune defense systems that sense bacterial infection, transmit alarm signals to the immune system, defeat intruding bacteria, and renew damaged and aging epithelial cells. nevertheless, mucosal bacterial pathogens have versatile pathogenic mechanisms that modulate the host inflammatory and immune responses, manipulate host cell death and survival signal pathways, and renovate the injured epithelium. these properties enable pathogens to adap ...201121763117
burden of rotavirus and other enteropathogens among children with diarrhea in burkina faso.objective: there is limited information available regarding the etiology of gastrointestinal infections in burkina faso. the aim of this study was to investigate the prevalence and epidemiology of enteric pathogens causing gastroenteritis in young children, with a focus on rotavirus, and to investigate the levels of malnutrition and other clinical factors in association with the severity of diarrhea. methods: a prospective study was undertaken from may 2009 to march 2010, covering the rainy and ...201121763172
lipopolysaccharide core structures and their correlation with genetic groupings of shigella strains; a novel core variant in shigella boydii type 16.bacteria shigella, the cause of shigellosis, evolved from intestinal bacteria escherichia coli. based on structurally diverse o-specific polysaccharide chains of the lipopolysaccharides (o-antigens), three from four shigella species are subdivided into multiple serotypes. the central oligosaccharide of the lipopolysaccharide called core is usually conserved within genus but five core types called r1-r4 and k-12 have been recognized in e. coli. structural data on the shigella core are limited to ...201121752864
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
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
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
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
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
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
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
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
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
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
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
rapid concentration and molecular enrichment approach for sensitive detection of escherichia coli/shigella in potable water samples.in this work, we used a rapid, simple, and efficient concentration and recovery procedure combined with a dna enrichment method (dubbed crename), that we coupled to an escherichia coli/shigella-specific real-time pcr (rtpcr) assay targeting the tuf gene, to sensitively detect e. coli/shigella in water. this integrated method was compared to the usepa culture-based method 1604 on mi agar in terms of analytical specificity, ubiquity, detection limit, and rapidity. none of the 179 non-e. coli/shige ...201121764965
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
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
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
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
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
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
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
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
changing species distribution and antimicrobial susceptibility pattern of shigella over a 29-year period (1980-2008).we studied changes in species distribution and antimicrobial resistance patterns of shigella during 1980-2008, using the diarrhoeal diseases surveillance system of dhaka hospital of icddr,b. in hospitalized patients shigella prevalence decreased steadily from 8-12% in the 1980s to 3% in 2008. endemic s. flexneri was the most commonly isolated species (54%). epidemic s. dysenteriae type 1 had two peaks in 1984 and 1993, but was not found after 2000, except for one case in 2004. the therapeutic op ...201120478088
effect of freeze-drying on viability and in vitro probiotic properties of a mixture of lactic acid bacteria and yeasts isolated from kefir.the effect of freeze-drying on viability and probiotic properties of a microbial mixture containing selected bacterial and yeast strains isolated from kefir grains (lactobacillus kefir, lactobacillus plantarum, lactococcus lactis, saccharomyces cerevisiae and kluyveromyces marxianus) was studied. the microorganisms were selected according to their potentially probiotic properties in vitro already reported. two types of formulations were performed, a microbial mixture (mm) suspended in milk and a ...201120822567
community perceptions of bloody diarrhoea in an urban slum in south asia: implications for introduction of a shigella vaccine.understanding local perceptions of disease causation could help public health officials improve strategies to prevent bloody diarrhoea. a cross-sectional survey was conducted in dhaka, bangladesh to elicit community beliefs about the causes of and prevention strategies for bloody diarrhoea. between march and june 2003, we interviewed 541 randomly selected respondents. overall, 507 (93%) respondents perceived that a vaccine could prevent bloody diarrhoea. if a vaccine provided lifetime protection ...201120546637
development of a pcr protocol for the detection of escherichia coli o157:h7 and salmonella spp. in surface water.escherichia coli o157:h7 and salmonella are pathogenic microorganisms that can cause severe gastrointestinal illness in humans. these pathogens may be transmitted in a variety of ways, including food and water. the presence of salmonella and e. coli o157:h7 in surface waters constitutes a potential threat to human health when used for either drinking or recreation. as with most waterborne pathogens, salmonella and e. coli o157:h7 are difficult to detect and enumerate with accuracy in surface wat ...201120714926
antidiarrheal activity, chemical and toxicity profile of berberis aristata.context: this study evaluated the in vitro and in vivo antidiarrheal activity, oral acute toxicological profile, and developed a chemical fingerprint of berberis aristata linn. (berberidaceae). materials and methods: the ethanol (by maceration) and aqueous (by soxhlet) extracts of berberis aristata bark were used for the study. the study involved the antimicrobial (minimum inhibitory concentration (mic) and minimum bactericidal concentration (mbc) by micro dilution) and antidiarrheal (castor oil ...201120738174
a disposable immunosensor for shigella flexneri based on multiwalled carbon nanotube/sodium alginate composite electrode.a novel shigella flexneri immunosensor based on horseradish peroxidase-labeled antibodies to s. flexneri (hrp-anti-s. flexneri) immobilized by physical adsorption on the multiwalled carbon nanotube (mwcnt)/sodium alginate (sa) composite modified screen-printed electrode surface was successfully fabricated. in this strategy, mwcnt/sa biocomposite acted as the matrix to adsorb and immobilize hrp-anti-s. flexneri. the modified electrodes were characterized with an atomic force microscope and cyclic ...201120816661
the crystal structures of the salmonella type iii secretion system tip protein sipd in complex with deoxycholate and chenodeoxycholate.the type iii secretion system (t3ss) is a protein injection nanomachinery required for virulence by many human pathogenic bacteria including salmonella and shigella. an essential component of the t3ss is the tip protein and the salmonella sipd and the shigella ipad tip proteins interact with bile salts, which serve as environmental sensors for these enteric pathogens. sipd and ipad have long central coiled coils and their n-terminal regions form α-helical hairpins and a short helix α3 that pack ...201121031487
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