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spa15 of shigella flexneri is secreted through the type iii secretion system and prevents staurosporine-induced apoptosis.shigella flexneri is a gram-negative, facultative intracellular pathogen that invades the colonic epithelium and causes bacillary dysentery. we previously demonstrated that s. flexneri inhibits staurosporine-induced apoptosis in infected epithelial cells and that a deltamxie mutant is unable to inhibit apoptosis. therefore, we hypothesized that an mxie-regulated gene was responsible for protection of epithelial cells from apoptosis. analysis of all mxie-regulated genes yielded no mutants that la ...200919805534
shigella infection of intestinal epithelium and circumvention of the host innate defense system.shigella, gram-negative bacteria closely related to escherichia coli, are highly adapted human pathogens that cause bacillary dysentery. although shigella have neither adherence factors nor flagella required for attaching or accessing the intestinal epithelium, shigella are capable of colonizing the intestinal epithelium by exploiting epithelial-cell functions and circumventing the host innate immune response. during shigella infection, they deliver many numbers of effectors through the type iii ...200919812985
the shigella dysenteriae serotype 1 proteome, profiled in the host intestinal environment, reveals major metabolic modifications and increased expression of invasive proteins.shigella dysenteriae serotype 1 (sd1) causes the most severe form of epidemic bacillary dysentery. we present the first comprehensive proteome analysis of this pathogen, profiling proteins from bacteria cultured in vitro and bacterial isolates from the large bowel of infected gnotobiotic piglets (in vivo). overall, 1061 distinct gene products were identified. differential display analysis revealed that sd1 cells switched to an anaerobic energy metabolism in vivo. high in vivo abundances of amino ...200919813213
comparative genomics reveal the mechanism of the parallel evolution of o157 and non-o157 enterohemorrhagic escherichia coli.among the various pathogenic escherichia coli strains, enterohemorrhagic e. coli (ehec) is the most devastating. although serotype o157:h7 strains are the most prevalent, strains of different serotypes also possess similar pathogenic potential. here, we present the results of a genomic comparison between ehecs of serotype o157, o26, o111, and o103, as well as 21 other, fully sequenced e. coli/shigella strains. all ehecs have much larger genomes (5.5-5.9 mb) than the other strains and contain sur ...200919815525
antibiotic therapy for shigella dysentery.shigella dysentery is a relatively common illness and occasionally causes death, worldwide. mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. the antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects.200919821387
prevalence of staphylococcus aureus and intestinal parasites among food handlers in sanliurfa, southeastern anatolia.food-borne diseases represent a persistent global health burden, and food handlers play a major role in their transmission. staphylococcus aureus carriage and intestinal parasitism are important risk factors for the contamination of food and water. this study was undertaken to determine the prevalence of staphylococcus aureus and intestinal parasites among food handlers working in sanliurfa, southeastern anatolia.200919823157
secretory iga-mediated neutralization of shigella flexneri prevents intestinal tissue destruction by down-regulating inflammatory circuits.shigella, a gram-negative invasive enteropathogenic bacterium responsible for bacillary dysentery, causes the rupture, invasion, and inflammatory destruction of the human colonic mucosa. we explored the mechanisms of protection mediated by shigella lps-specific secretory iga (siga), the major mucosal ab induced upon natural infection. bacteria, siga, or siga-s. flexneri immune complexes were administered into rabbit ligated intestinal loops containing a peyer's patch. after 8 h, localizations of ...200919828639
beneficial role of green plantain [musa paradisiaca] in the management of persistent diarrhea: a prospective randomized trial.to evaluate the beneficial effects of green plantain-based diet on stool volume, frequency and weight gain as compared with a traditional yogurt-based diet in children with persistent diarrhea.200919828902
how autophagy regulates the host cell signaling associated with the postpartum bacteria cocoon experienced as a danger signal.shigella, the causative agent of human bacillary dysentery, invades the host cell, rapidly breaking the phagosome and multiplying in the cytosol. here, we summarize our recent work showing the targeting of the leftover membrane remnants to autophagy together with trapped membrane-associated signaling molecules recruited during the immediate early entry step. we suggest that this mechanism participates in the bacteria-dependent orchestration of the cell response. moreover, we propose that this si ...200919829050
effect of x-ray treatments on inoculated escherichia coli o157: h7, salmonella enterica, shigella flexneri and vibrio parahaemolyticus in ready-to-eat shrimp.this study was conducted to evaluate the inactivation effect of x-ray treatments on escherichia coli o157: h7, salmonella enteric (s. enterica), shigella flexneri (s. flexneri) and vibrio parahaemolyticus (v. parahaemolyticus) artificially inoculated in ready-to-eat (rte) shrimp. a mixed culture of three strains of each tested pathogen was used to inoculate rte shrimp. the shrimp samples were inoculated individually with selected pathogenic bacteria then aseptically placed in sterile plastic cup ...200919835772
the mannitol operon repressor mtlr belongs to a new class of transcription regulators in bacteria.many bacteria express phosphoenolpyruvate-dependent phosphotransferase systems (pts). the mannitol-specific pts catalyze the uptake and phosphorylation of d-mannitol. the uptake system comprises several genes encoded in the single operon. the expression of the mannitol operon is regulated by a proposed transcriptional factor, mannitol operon repressor (mtlr) that was first studied in escherichia coli. here we report the first crystal structures of mtlr from vibrio parahemeolyticus (vp-mtlr) and ...200919840941
escherichia coli as reservoir for macrolide resistance genes.the plasmid-borne mph(a) gene that confers resistance to azithromycin and has recently emerged in shigella sonnei is present in multidrug- and non-multidrug-resistant escherichia coli isolates from 4 continents. further spread of mph(a) to shigella and salmonella spp. may be expected.200919861064
the pathogenic properties of a novel and conserved gene product, kerv, in proteobacteria.identification of novel virulence factors is essential for understanding bacterial pathogenesis and designing antibacterial strategies. in this study, we uncover such a factor, termed kerv, in proteobacteria. experiments carried out in a variety of eukaryotic host infection models revealed that the virulence of a pseudomonas aeruginosa kerv null mutant was compromised when it interacted with amoebae, plants, flies, and mice. bioinformatics analyses indicated that kerv is a hypothetical methyltra ...200919779606
genome sequences of escherichia coli b strains rel606 and bl21(de3).escherichia coli k-12 and b have been the subjects of classical experiments from which much of our understanding of molecular genetics has emerged. we present here complete genome sequences of two e. coli b strains, rel606, used in a long-term evolution experiment, and bl21(de3), widely used to express recombinant proteins. the two genomes differ in length by 72,304 bp and have 426 single base pair differences, a seemingly large difference for laboratory strains having a common ancestor within t ...200919786035
enteroinvasive escherichia coli vs. shigella flexneri: how different patterns of gene expression affect virulence.important features of the enteroinvasive escherichia coli (eiec) phenotype and gene expression likely to confer eiec with a lower ability to cause disease than shigella flexneri were described here for the first time. to confirm the lower pathogenicity of eiec, we have analyzed the keratoconjunctivitis developed in guinea-pigs with eiec or s. flexneri. shigella flexneri induced a more pronounced proinflammatory response, whereas eiec induced a mild form of the disease. eiec showed a significantl ...200919889166
pneumonia caused by shigella sonnei in man returned from india. 200919891897
helicobacter pylori induces mapk phosphorylation and ap-1 activation via a nod1-dependent mechanism.helicobacter pylori rapidly activates mapks and transcription factors, nf-kappab and ap-1, in gastric epithelial cells following host attachment. activation of these signal transducers is largely dependent on the cag pathogenicity island (cagpai)-encoded type iv secretion system. h. pylori was shown to translocate peptidoglycan through the type iv secretion system, which is recognized by the pathogen recognition molecule, nod1, thus resulting in nf-kappab activation. the mechanisms of h. pylori- ...200920007577
trends in antimicrobial resistance in shigella species in karachi, pakistan.shigellosis is a common cause of morbidity, especially in the very young and old, in developing countries. the disease is treated with antibiotics. surveillance of antimicrobial resistance trends is essential owing to the global emergence of antimicrobial resistance.200920009283
purification, characterization, and gene cloning of glucose-1-phosphatase from citrobacter braakii.citrobacter braakii produced an intracellular acid glucose phosphatase (agpc) which was purified 986 fold to homogeneity with the specific activity of 286 units/mg. agpc hydrolyzed a wide variety of phosphorylated compounds with high activity for glucose-1-phosphate and glucose-6-phosphate. the optimum ph and temperature for the enzyme activity was ph 5.0 and 45 degrees c, respectively. the km value for glucose-1-phosphate was 5.12 mm with a vmax 27.8 u mg(-1). its molecular weight was 46 kda by ...200919940380
vaccines for enteric diseases: update on recent developments.the 5th international conference on vaccines for enteric diseases (ved) attracted more than 250 delegates, mainly from industrialized countries. a total of 56 papers were presented and 46 posters were displayed to update recent developments in the field of enteric diseases and vaccine development. this 3-day event enabled academic research institutions, pharmaceutical and biotech companies, and international donors to get a sense of what has been going on since the last ved conference in 2007. t ...200919943760
inactivated and subunit vaccines to prevent shigellosis.shigellosis remains a formidable disease globally, with children of the developing world bearing the greatest number of infections. the need for an affordable, safe and efficacious vaccine has persisted for decades. vaccines to prevent shigellosis can be divided into living and nonliving approaches. several nonliving shigella vaccines are currently at different stages of development and show substantial promise. outlined here is an overview of multiple nonliving vaccine technologies, highlightin ...200919943764
in this issue.shigellosis, dysentery - by whatever name - don't kiss the chimps: pp. 5029-5045with a 10-15% mortality rate when untreated in young children and immunedeficient patients, over one million deaths per year are attributable to this primate/human-only disease. furthermore, the shigella spp. have developed resistance to b-lactam, tetracycline, and aminoglycoside antibiotics very rapidly. a non-primate model of the disease is based on gnotobiotic piglets. aerobically grown bacteria shift to anaerobic ...200919921678
a changing picture of shigellosis in southern vietnam: shifting species dominance, antimicrobial susceptibility and clinical presentation.shigellosis remains considerable public health problem in some developing countries. the nature of shigellae suggests that they are highly adaptable when placed under selective pressure in a human population. this is demonstrated by variation and fluctuations in serotypes and antimicrobial resistance profile of organisms circulating in differing setting in endemic locations. antimicrobial resistance in the genus shigella is a constant threat, with reports of organisms in asia being resistant to ...200920003464
spatial distribution of diarrhoea and microbial quality of domestic water during an outbreak of diarrhoea in the tshikuwi community in venda, south africa.total microbial quality assessment and geographical information system were used for evaluating the quality of water and the spatial distribution of diarrhoea cases in tshikuwi, a rural community in south africa, during an outbreak of diarrhoea. the water-abstraction points included two groundwater storage tanks, namely tank 1 and tank 2 and the khandanama river. indicator microbial counts for total coliforms, faecal coliforms, enterococci, and heterotrophic bacteria exceeded the limit for no ri ...200919902801
studies on the antidiarrhoeal activity of aegle marmelos unripe fruit: validating its traditional usage.aegle marmelos (l.) correa has been widely used in indigenous systems of indian medicine due to its various medicinal properties. however, despite its traditional usage as an anti-diarrhoeal there is limited information regarding its mode of action in infectious forms of diarrhoea. hence, we evaluated the hot aqueous extract (decoction) of dried unripe fruit pulp of a. marmelos for its antimicrobial activity and effect on various aspects of pathogenicity of infectious diarrhoea.200919930633
a unified approach to molecular epidemiology investigations: tools and patterns in california as a case study for endemic shigellosis.shigellosis causes diarrheal disease in humans from both developed and developing countries, and multi-drug resistance is an emerging problem. the objective of this study is to present a unified approach that can be used to characterize endemic and outbreak patterns of shigellosis using use a suite of epidemiologic and molecular techniques. the approach is applied to a california case study example of endemic shigellosis at the population level.200919930709
[development of taqman real-time pcr in detection of aeromonas hydrophila].to develop a taqman real-time pcr for the detection of aeromonas hydrophila.200919954074
[investigation of a norovirus outbreak through contaminated centralized water supply system].to investigate the etiology and source of an infectious diarrhea outbreak and control the epidemic.200919954078
the immunogenic siga enterotoxin of shigella flexneri 2a binds to hep-2 cells and induces fodrin redistribution in intoxicated epithelial cells.we have previously shown that the enterotoxin siga which resides on the she pathogenicity island (pai) of s. flexneri 2a is an autonomously secreted serine protease capable of degrading casein. we have also demonstrated that siga is cytopathic for hep-2 cells and plays a role in the intestinal fluid accumulation associated with s. flexneri infections.200920011051
diarrhea associated hemolytic uremic syndrome: a 3-year picu experience from nepal. 200920072865
diarrheagenic escherichia coli in sub-saharan africa: status, uncertainties and necessities.diarrhea is a leading cause of illness and death, particularly in developing countries. enteropathogenic escherichia coli, enterotoxigenic e. coli (etec), enteroinvasive e. coli, enterohemorrhaghic e. coli (ehec), enteroaggregative e. coli (eaec) and diffusely adherent e. coli (daec) have been associated with diarrheal disease in different parts of africa, particularly among young children, hiv-positive individuals, and visitors from abroad. each of these e. coli pathotypes uses distinct mechani ...200920061678
bacterial effector binding to ribosomal protein s3 subverts nf-kappab function.enteric bacterial pathogens cause food borne disease, which constitutes an enormous economic and health burden. enterohemorrhagic escherichia coli (ehec) causes a severe bloody diarrhea following transmission to humans through various means, including contaminated beef and vegetable products, water, or through contact with animals. ehec also causes a potentially fatal kidney disease (hemolytic uremic syndrome) for which there is no effective treatment or prophylaxis. ehec and other enteric patho ...200920041225
antibacterial and antifungal activities of some mexican medicinal plants.in mexico about 4,000 plant species have some medicinal use. the aim of this work was to evaluate the antimicrobial activity of six mexican medicinal plants against fungi and gram-positive and gram-negative bacteria. methanolic extracts were prepared from the mexican medicinal plants amphypteringium adstrigens, castella tortuosa, coutarea latiflora, ibervillea sonorae, jatropha cuneata, and selaginella lepidophylla. the antibacterial and antifungal activities of the plants were determined by the ...200920041800
multilocus variable-number tandem repeat analysis for molecular typing and phylogenetic analysis of shigella flexneri.shigella flexneri is one of the causative agents of shigellosis, a major cause of childhood mortality in developing countries. multilocus variable-number tandem repeat (vntr) analysis (mlva) is a prominent subtyping method to resolve closely related bacterial isolates for investigation of disease outbreaks and provide information for establishing phylogenetic patterns among isolates. the present study aimed to develop an mlva method for s. flexneri and the vntr loci identified were tested on 242 ...200920042119
enteric pathogens in hiv/aids from a tertiary care hospital.patterns of enteric infections in hiv in developing countries may differ in several important ways from developed countries, the knowledge of which can often guide therapy when resource limitations hamper the exact diagnosis of the etiological agent in hiv-associated diarrhea.200920049303
[overdiagnosis of amebiasis in children with dysentery].there are morphologically identical amebaes, but with differences that can distinguish them; one as pathogenic: entamoeba histolytica, and the other: entamoeba dispar, as inoffensive. that brought the new hypothesis that many of the cases treated as amebiasis, weren't so.200920049395
prevalence of intestinal parasitic and bacterial pathogens in diarrhoeal and non-diarroeal human stools from vhembe district, south africa.in the present study, a cross-sectional survey of intestinal parasitic and bacterial infections in relation to diarrhoea in vhembe district and the antimicrobial susceptibility profiles of isolated bacterial pathogens was conducted. stool samples were collected from 528 patients attending major public hospitals and 295 children attending two public primary schools and were analyzed by standard microbiological and parasitological techniques. entamoeba histolytica/e. dispar (34.2%) and cryptospori ...200920099757
[the effect of trimethoprim-sulfamethoxazole in blastocystis hominis infection].the aim of this study was to investigate clinical findings and the effects of trimethoprim-sulfamethoxazole (tmp-smx) in cases of blastocystosis. a total of 37 cases whose stool specimens were sent to the parasitology laboratory from the outpatient clinics of our hospital for various reasons were included in the study. only five or more blastocystis hominis were found during examination with direct wet mount using the 40x objective. the stool specimens were tested for other agents (salmonella sp ...200920101575
antimicrobial resistance induced by genetic changes.decoding the mechanisms of resistance to antibiotics is essential in fighting a phenomenon, which is amplifying everyday due to the uncontrolled excessive and many times unjustified use of anti-microbial substances. at present it has become a matter of public health, together with the resistance of mycobacterium tuberculosis to tuberculostatic or the spreading of the aids virus which not only affects the european countries but the entire globe. this paper presents the genic mutations taking plac ...200920108530
[characteristics of dysentery-causing strains isolated from patients and carriers in republic of south ossetia during period of humanitarian disaster]. 200920095424
resistances of antibiotics and heavy metals in enterobacteriaceae spp. isolated from gills and intestines of achanthobrama marmid (heckel,1843) from sir dam lake turkey.a total of 94 bacteria, associated with wild achanthobrama marmid (heckel, 1843) in sir dam lake of turkey identified. subsequently selected isolates were characterized and identified to the genus level the 94 members of enterobacteriaceae were isolated in the gills and intestines, and among the isolates, e. coli were represented at a rate of 55%, shigella spp. at a rate of 21%, salmonella spp. at a rate of 9%, citrobacter spp. at a rate of 9%, klebsiella spp. at a rate of 3% and proteus spp., a ...200920112859
[campylobacter spp. as a leading cause of human bacterial gastroenteritis in selected region of poland].the results of the epidemiological analysis of campylobacteriosis reported by regional laboratory of sanitary epidemiological station in bielsko-biala (psse bielsko-biala), silesia voivodeship in poland are presented. from august 2006 to july 2009, stool samples from diarrhea cases were examined for the presence of campylobacter spp. as well as salmonella, shigella, yersinia, enteropathogenic (epec) and verotoxigenic (vtec) e. coli. the most frequently isolated species of campylobacter spp. was ...200920120952
[prof. kazimierz lachowicz (md)--100th anniversary of birthday].prof. kazimierz lachowicz, md, dipl. medical microbiology, was the founder and the first director of the three regional branches of national institute of hygiene (nih),--in stanisławów (eastern poland) (1937-43), now in ukrainian ivano-frankivsk, maritime in gdynia (1945), now institute of maritime and tropical medicine, and in gdańsk (1945-52). in nih, warsaw, 1953-75 he directed intestinal infection laboratory of bacteriological dept., later founded and directed the national shigella centre as ...200920120962
reduction in infection risk through treatment of microbially contaminated surfaces with a novel, portable, saturated steam vapor disinfection system.surface-mediated infectious disease transmission is a major concern in various settings, including schools, hospitals, and food-processing facilities. chemical disinfectants are frequently used to reduce contamination, but many pose significant risks to humans, surfaces, and the environment, and all must be properly applied in strict accordance with label instructions to be effective. this study set out to determine the capability of a novel chemical-free, saturated steam vapor disinfection syst ...200918834748
quinolone-induced arthropathy: an update focusing on new mechanistic and clinical data.quinolones possess favourable antibacterial and pharmacokinetic characteristics and are often used as anti-infective agents in adults. they are contraindicated in children and adolescents because they damage weight-bearing joints in juvenile animals. in addition, they possess a tendotoxic potential. since ciprofloxacin has been used off-label for decades in children and adolescents, it is known today that no pronounced risks for arthropathies or tendinopathies exist in humans. recently published ...200918835137
design, synthesis and in vitro microbiological evaluation of 6,6-dimethyl-7,9-diaryl-1,2,4,8-tetraazaspiro[4.5]decan-3-thiones--a new series of 'tailor-made' compounds.some novel 'tailor-made' compounds, 6,6-dimethyl-7,9-diaryl-1,2,4,8-tetraazaspiro[4.5]decan-3-thiones 23-27 have been studied for their in vitro antibacterial activity against staphylococcus aureus, beta-heamolytic streptococcus, vibreo cholerae, salmonella typhii, shigella felxneri, escherichia coli, klebsiella pneumonia, pseudomonas aeruginosa and anti-fungal activity against aspergillus flavus, mucor, rhizopus and microsporum gypsuem. compounds 24 and 25 exerted potent antibacterial activity ...200918830884
design, synthesis, characterization and in vitro antimicrobial evaluation of 4,6-diaryl-4,5-dihydro-2-phenyl-2h-indazol-3-ols.new 4,6-diaryl-4,5-dihydro-2-phenyl-2h-indazol-3-ols 25-32 were designed, synthesized and in vitro microbially evaluated using clinically isolated bacterial strains viz staphylococcus aureus, beta-heamolytic streptococcus, vibreo cholerae, salmonella typhii, shigella felxneri and fungal strains viz aspergillus flavus, mucor, rhizopus and microsporum gypsuem. results of this study showed that the nature of the substituents on the phenyl rings viz., methyl, methoxy, chloro, nitro as well as the br ...200918825556
metal based isatin-derived sulfonamides: their synthesis, characterization, coordination behavior and biological activity.some isatin derived sulfonamides and their transition metal [co(ii), cu(ii), ni(ii), zn(ii)] complexes have been synthesized and characterized. the structure of synthesized compounds and their nature of bonding have been inferred on the basis of their physical (magnetic susceptibility and conductivity measurements), analytical (elemental analyses) and spectral (ir, (1)h nmr and (13)c nmr) properties. an octahedral geometry has been suggested for co(ii), ni(ii) and zn(ii) and square-planar for cu ...200918825557
guideline for the investigation and initial therapy of diarrhea-negative hemolytic uremic syndrome.this guideline for the investigation and initial treatment of atypical hemolytic uremic syndrome (hus) is intended to offer an approach based on opinion, as evidence is lacking. it builds on the current ability to identify the etiology of specific diagnostic sub-groups of hus. hus in children is mostly due to infection, enterohemorrhagic escherichia coli (ehec), shigella dysenteriae type 1 in some geographic regions, and invasive streptococcus pneumoniae. these sub-groups are relatively straight ...200918800230
nlrc4/ipaf: a card carrying member of the nlr family.the nod-like receptor (nlr) family of proteins is involved in the regulation of innate immune responses and cell death pathways. recent findings show that the nlr family member nlrc4 (also known as ipaf) has important roles in innate immune responses to gram-negative bacteria. macrophages infected with legionella pneumophila, salmonella typhimurium, shigella flexneri, or pseudomonas aeruginosa activate caspase-1 in an nlrc4-dependent manner leading to macrophage cell death and the release of pro ...200918819842
the in vitro anti-pathogenic activity of immunoglobulin concentrates extracted from ovine blood.an immunoglobulin-rich fraction has been prepared from ovine blood in our laboratory. we have investigated its antibacterial activity and binding activity to pathogenic whole cell antigens, lipopolysaccharide (lps) and staphylococcal enterotoxin b. ovine immunoglobulin concentrate (oic) comprised about 73 +/- 2% of igg and 11 +/- 1% of igm on a protein basis. it inhibited the growth of all 13 strains of pathogens tested, but the inhibitory activity varied according to bacterial strain. the inhib ...200918769875
acanthamoeba castellanii an environmental host for shigella dysenteriae and shigella sonnei.the interaction between shigella dysenteriae or shigella sonnei and acanthamoeba castellanii was studied by viable counts, gentamicin assay and electron microscopy. the result showed that shigella dysenteriae or shigella sonnei grew and survived in the presence of amoebae for more than 3 weeks. gentamicin assay showed that the shigella were viable inside the acanthamoeba castellanii which was confirmed by electron microscopy that showed the shigella localized in the cytoplasm of the acanthamoeba ...200918712360
novel chimeric beta-lactamase ctx-m-64, a hybrid of ctx-m-15-like and ctx-m-14 beta-lactamases, found in a shigella sonnei strain resistant to various oxyimino-cephalosporins, including ceftazidime.the plasmid-mediated novel beta-lactamase ctx-m-64 was first identified in shigella sonnei strain uih-1, which exhibited resistance to cefotaxime (mic, 1,024 microg/ml) and ceftazidime (mic, 32 microg/ml). the amino acid sequence of ctx-m-64 showed a chimeric structure of a ctx-m-15-like beta-lactamase (n- and c-terminal moieties) and a ctx-m-14-like beta-lactamase (central portion, amino acids 63 to 226), suggesting that it originated by homologous recombination between the corresponding genes. ...200918955524
a genomic distance based on mum indicates discontinuity between most bacterial species and genera.the fundamental unit of biological diversity is the species. however, a remarkable extent of intraspecies diversity in bacteria was discovered by genome sequencing, and it reveals the need to develop clear criteria to group strains within a species. two main types of analyses used to quantify intraspecies variation at the genome level are the average nucleotide identity (ani), which detects the dna conservation of the core genome, and the dna content, which calculates the proportion of dna share ...200918978054
the temporal dynamics of slightly deleterious mutations in escherichia coli and shigella spp.the shigella are recently emerged clones of escherichia coli, which have independently adopted an intracellular pathogenic lifestyle. we examined the molecular evolutionary consequences of this niche specialization by comparing the normalized, directional frequency profiles of unique polymorphisms within 2,098 orthologues representing the intersection of five e. coli and four shigella genomes. we note a surfeit of at-enriching changes (gc-->at), transversions, and nonsynonymous changes in the sh ...200918984902
detection of escherichia coli, salmonella spp., shigella spp., yersinia enterocolitica, vibrio cholerae, and campylobacter spp. enteropathogens by 3-reaction multiplex polymerase chain reaction.the magnitude of bacterial diarrhea in developing countries is largely unknown because affordable detection methods are not available. we have developed a polymerase chain reaction (pcr)-based assay for use in areas with limited resources to screen for diarrheogenic strains from clinical isolates. to simplify the assay and minimize reagents, our method implemented the use of plasmids rather than bacteria as template controls and the use of bacterial suspensions or crude dna preparations rather t ...200918990527
small-molecule type iii secretion system inhibitors block assembly of the shigella type iii secreton.type iii secretion systems (t3sss) are essential virulence devices for many gram-negative bacteria that are pathogenic for plants, animals, and humans. they serve to translocate virulence effector proteins directly into eukaryotic host cells. t3sss are composed of a large cytoplasmic bulb and a transmembrane region into which a needle is embedded, protruding above the bacterial surface. the emerging antibiotic resistance of bacterial pathogens urges the development of novel strategies to fight b ...200918996990
ceramide and cerebrosides from the octocoral sarcophyton ehrenbergi.chemical investigation of the octocoral sarcophyton ehrenbergi, collected at the dongsha islands, taiwan, has led to the isolation of a known ceramide (1) and two new cerebrosides, sarcoehrenosides a (2) and b (4), along with three known cerebrosides (3, 5, and 6). the structures of the new compounds were established by spectroscopic and chemical methods. sarcoehrenoside a (2) differs from previously known marine cerebrosides in that it possesses a rare alpha-glucose moiety. compounds 1-6 were e ...200919006372
the molecular evolutionary history of shigella spp. and enteroinvasive escherichia coli.shigellosis, which caused by shigella and enteroinvasive escherichia coli (eiec), was still a threat to public health. compelling evidence indicates that shigella species and eiec are derived from multiple origins of e. coli and form a single pathovar. eiec strains are regarded as precursors of 'full-blown'shigella evolved from e. coli. by gain and loss of functions, shigella and eiec became successful human pathogens through convergent evolution from diverse genomic backgrounds.200919000785
diversity of tight junctions (tjs) between gastrointestinal epithelial cells and their function in maintaining the mucosal barrier.the gastrointestinal epithelium, which is covered by a single layer of epithelial cells, including enterocytes, intraepithelial lymphocytes, goblet cells, microfold cells, and dendritic cells, serves as a protective barrier separating luminal contents from the underlying tissue compartments. the epithelium plays an important role in the first line of host defense against a variety of pathogens, as well as maintaining the homeostasis in gastrointestinal tract. all these epithelial cells express j ...200918938254
simultaneous detection of enteric bacteria from surface waters by qpcr in comparison with conventional bacterial indicators.a rapid quantitative polymerase chain reaction (qpcr) method was developed for simultaneous detection of enteric bacteria from surface waters by utilizing a pair of universal primers which targeted four bacteria strains, namely shigella dysenteriae, vibrio cholerae, salmonella typhimurium, and escherichia coli. it was estimated that the qpcr method had a 94% confidence, and a detection limit as 2.7 e. coli cells per sample in undiluted dna extracts. the qpcr method was applied for the bacteriolo ...200918931927
role for the chlamydial type iii secretion apparatus in host cytokine expression.in many important human pathogens, such as shigella and salmonella spp., the bacterial type iii secretion (t3s) apparatus is required to initiate inflammation via activation of caspase-1- or nf-kappab-dependent genes. using an ex vivo infection model, the goal of the present study was to determine whether the chlamydial t3s apparatus also modulates the host inflammatory response. infections of mouse peritoneal macrophages were performed with chlamydia muridarum, and the expression of inflammator ...200918852236
bacterial enteropathogens of neonates admitted to an urban diarrhoeal hospital in bangladesh.data on the aetiology of diarrhoea in neonates are scarce, especially from developing countries including bangladesh. a retrospective review of the electronic database of the microbiology laboratory of the international centre for diarrhoeal disease research, bangladesh (icddr,b), was carried out to examine enteropathogens associated with diarrhoea in neonates. stool specimens of the neonates on admission to the dhaka hospital of icddr,b were collected and sent to the laboratory for direct plati ...200918840632
tight junctions as targets of infectious agents.the epithelial barrier is a critical border that segregates luminal material from entering tissues. essential components of this epithelial fence are physical intercellular structures termed tight junctions. these junctions use a variety of transmembrane proteins coupled with cytoplasmic adaptors, and the actin cytoskeleton, to attach adjacent cells together thereby forming intercellular seals. breaching of this barrier has profound effects on human health and disease, as barrier deficiencies ha ...200919059200
seasonal stability of cladophora-associated salmonella in lake michigan watersheds.the bacterial pathogens shigella, salmonella, campylobacter, and shiga toxin-producing e. coli (stec) were recently found to be associated with cladophora growing in southern lake michigan. preliminary results indicated that the salmonella strains associated with cladophora were genetically identical to each other. however, because of the small sample size (n=37 isolates) and a lack of information on spatial-temporal relationships, the nature of the association between cladophora and salmonella ...200919059626
prevalence of sulfonamide resistance genes in bacterial isolates from manured agricultural soils and pig slurry in the united kingdom.the prevalences of three sulfonamide resistance genes, sul1, sul2, and sul3 and sulfachloropyridazine (scp) resistance were determined in bacteria isolated from manured agricultural clay soils and slurry samples in the united kingdom over a 2-year period. slurry from tylosin-fed pigs amended with scp and oxytetracycline was used for manuring. isolates positive for sul genes were further screened for the presence of class 1 and 2 integrons. phenotypic resistance to scp was significantly higher in ...200919064898
lactobacilli facilitate maintenance of intestinal membrane integrity during shigella dysenteriae 1 infection in rats.lactobacilli are used in various dairy products and fermented foods for their potential health beneficial effects. recently we reported the protective role of lactobacillus rhamnosus and lactobacillus acidophilus during shigella dysenteriae 1 infection. nevertheless, investigations on the membrane-stabilizing effect of l. rhamnosus and l. acidophilus have not been done. hence, the present study evaluated the effect of l. rhamnosus and l. acidophilus on the maintenance of intestinal membrane inte ...200919036564
selective ccr2-targeted macrophage depletion ameliorates experimental mesangioproliferative glomerulonephritis.the ccl2/ccr2 chemokine/receptor axis directs the chemotaxis of infiltrating monocytes/macrophages and t cells and plays a pivotal role in tissue damage and fibrosis in kidney diseases. the eradication of the activated leucocytes should diminish the production of inflammatory mediators, limit tissue damage and ameliorate disease. a recombinant fusion protein (opl-ccl2-lpm) comprised of the human ccl2 (monocyte chemoattractant protein-1) chemokine fused to a truncated form of the enzymatically ac ...200919040610
antigen-specific b memory cell responses to lipopolysaccharide (lps) and invasion plasmid antigen (ipa) b elicited in volunteers vaccinated with live-attenuated shigella flexneri 2a vaccine candidates.we evaluated b memory responses in healthy adult volunteers who received one oral dose of live-attenuated shigella flexneri 2a vaccine. lps-specific b(m) cells increased from a median of 0 at baseline to 20 spot forming cells (sfc)/10(6) expanded cells following vaccination (p=0.008). a strong correlation was found between post-vaccination anti-lps b(m) cell counts and peak serum anti-lps igg titers (rs=0.95, p=0.0003). increases in b(m) specific for ipab approaching significance were also obser ...200919022324
interaction of enteric bacterial pathogens with murine embryonic stem cells.embryonic stem (es) cells are susceptible to genetic manipulation and retain the potential to differentiate into diverse cell types, which are factors that make them potentially attractive cells for studying host-pathogen interactions. murine es cells were found to be susceptible to invasion by salmonella enterica serovar typhimurium and shigella flexneri and to the formation of attaching and effacing lesions by enteropathogenic escherichia coli. s. enterica serovar typhimurium and s. flexneri c ...200919029302
inferring genomic flux in bacteria.acquisition and loss of genetic material are essential forces in bacterial microevolution. they have been repeatedly linked with adaptation of lineages to new lifestyles, and in particular, pathogenicity. comparative genomics has the potential to elucidate this genetic flux, but there are many methodological challenges involved in inferring evolutionary events from collections of genome sequences. here we describe a model-based method for using whole-genome sequences to infer the patterns of gen ...200919015321
espt triggers formation of lamellipodia and membrane ruffles through activation of rac-1 and cdc42.subversion of the eukaryotic cell cytoskeleton is a virulence strategy employed by many bacterial pathogens. due to the pivotal role of rho gtpases in actin dynamics they are common targets of bacterial effector proteins and toxins. ipgb1, ipgb2 (shigella), sifa, sifb (salmonella) and map and espm (attaching and effacing pathogens) constitute a family of type iii secretion system effectors that subverts small gtpase signalling pathways. in this study we identified and characterized espt from cit ...200919016787
mxic is secreted by and controls the substrate specificity of the shigella flexneri type iii secretion apparatus.many gram-negative pathogenic bacteria use a type iii secretion (t3s) system to interact with cells of their hosts. mechanisms controlling the hierarchical addressing of needle subunits, translocators and effectors to the t3s apparatus (t3sa) are still poorly understood. we investigated the function of mxic, the member of the yopn/inve/sepl family in the shigella flexneri t3s system. inactivation of mxic led specifically to a deregulated secretion of effectors (including ipaa, ipgd, icsb, ipgb2, ...200919017268
shigella flexneri type iii secretion system effectors ospb and ospf target the nucleus to downregulate the host inflammatory response via interactions with retinoblastoma protein.ospf, ospg and ipah(9.8) are type iii secretion system (t3ss) effectors of shigella flexneri that downregulate the host innate immune response. ospf modifies mitogen-activated protein kinase pathways and polymorphonuclear leucocyte transepithelial migration associated with shigella invasion. ospf also localizes in the nucleus to mediate chromatin remodelling, resulting in reduced transcription of inflammatory cytokines. we now report that ospb can be added to the set of s. flexneri t3ss effector ...200919017275
repression of galp, the galactose transporter in escherichia coli, requires the specific regulator of n-acetylglucosamine metabolism.soupene et al. [j. bacteriol. (2003) 185 5611-5626] made the unexpected observation that the presence of a mutation, in the gene for the n-acetylglucosamine repressor, nagc, increased the growth rate of escherichia coli mg1655 on galactose, an unrelated sugar. we have found that nagc, binds to a single, high-affinity site overlapping the promoter of galp (galactose permease) gene and that expression of galp is repressed by a combination of nagc, galr and gals. in addition to the previously ident ...200919007420
genotypic and phenotypic diversity among induced, stx2-carrying bacteriophages from environmental escherichia coli strains.shiga toxin 2 (stx(2)) gene-carrying bacteriophages have been shown to convert escherichia coli strains to shiga toxin-producing escherichia coli (stec). in this study, 79 e. coli strains belonging to 35 serotypes isolated from wastewaters of both human and animal origin were examined for the presence of stx(2)-carrying bacteriophages in their genomes. the lytic cycle of the bacteriophages was induced by mitomycin, and the bacteriophage fraction was isolated and used for morphological and geneti ...200919011056
tlr4 and myd88 control protection and pulmonary granulocytic recruitment in a murine intranasal rsv immunization and challenge model.an intranasal vaccine composed of toll-like receptor 2 (tlr2) ligand neisseria meningitidis outer membrane proteins and toll-like receptor 4 (tlr4) ligand shigella flexneri lipopolysaccharide (lps) (protollin) and enriched respiratory syncytial virus (rsv) proteins (ersv) has been demonstrated to promote balanced th1/th2 responses without eosinophil recruitment and to protect against challenge in mouse models. we used tlr2, tlr4 and myeloid differentiation factor 88 (myd88) knock-out (-/-) mice ...200919013492
extensive antibody cross-reactivity among infectious gram-negative bacteria revealed by proteome microarray analysis.antibodies provide a sensitive indicator of proteins displayed by bacteria during sepsis. because signals produced by infection are naturally amplified during the antibody response, host immunity can be used to identify biomarkers for proteins that are present at levels currently below detectable limits. we developed a microarray comprising approximately 70% of the 4066 proteins contained within the yersinia pestis proteome to identify antibody biomarkers distinguishing plague from infections ca ...200919112181
antimicrobial activity of prulifloxacin tested against a worldwide collection of gastroenteritis-producing pathogens, including those causing traveler's diarrhea.prulifloxacin, the prodrug of ulifloxacin (active component), is a newer fluoroquinolone with broad activity against enteric and nonenteric gram-negative bacilli. ulifloxacin and other oral comparator agents were tested for activity against 582 gastroenteritis strains from global surveillance studies. ulifloxacin was highly active against escherichia coli, salmonella spp., shigella spp., yersinia spp., vibrio spp., aeromonas spp., and plesiomonas spp. (mic(50)s and mic(90)s, <or=0.03 microg/ml a ...200919114678
diagnosis and prevalence of enteropathogenic bacteria in children less than 5 years of age with acute diarrhea in tehran children's hospitals.acute diarrhea disease is the second cause of death among all infectious diseases in children younger than 5 years of age worldwide. the aim of this study was to employ a combination of biochemical, microbiological and molecular diagnostic techniques to investigate the stools of iranian children with acute diarrhea for bacterial enteropathogens.200919117609
bacterial particle endocytosis by epithelial cells is selective and enhanced by tumor necrosis factor receptor ligands.bacterial pathogens use virulence strategies to invade epithelial barriers, but active processes of epithelial cells may also contribute to the endocytosis of microbial particles. to focus on the latter, we studied the uptake of fixed and fluorescently labeled bacterial particles in intestinal and bronchoepithelial cell cultures and found it to be enhanced in caco-2bbe and nci-h292 cells after treatment with tumor necrosis factor alpha and an agonist antibody against the lymphotoxin beta recepto ...200919129472
genetics and environmental regulation of shigella iron transport systems.shigella spp. have transport systems for both ferric and ferrous iron. the iron can be taken up as free iron or complexed to a variety of carriers. all shigella species have both the feo and sit systems for acquisition of ferrous iron, and all have at least one siderophore-mediated system for transport of ferric iron. several of the transport systems, including sit, iuc/iuta (aerobactin synthesis and transport), fec (ferric di-citrate uptake), and shu (heme transport) are encoded within pathogen ...200919130265
outbreaks of shigella sonnei infections in denmark and australia linked to consumption of imported raw baby corn.we investigated an outbreak of shigella sonnei infections in denmark and australia associated with imported baby corn from one packing shed in thailand. we reviewed nationwide surveillance and undertook case finding, food trace-back and microbiological investigation of human, food and environmental samples. a recall of baby corn and sugar snaps was based on descriptive epidemiological evidence. in denmark, we undertook a retrospective cohort study in one workplace. in total, 215 cases were labor ...200919134229
frequency of isolation of various subtypes and antimicrobial resistance of shigella from urban slums of karachi, pakistan.shigellosis remains a major public health problem in developing countries. antimicrobial resistance has complicated the empirical treatment. knowledge of serotypes is crucial in vaccine development, as cross-protection between various serotypes is limited. therefore we conducted a prospective study to determine the frequency of isolation of shigella serotypes and antimicrobial resistance.200919135399
safety and immunogenicity of sc599, an oral live attenuated shigella dysenteriae type-1 vaccine in healthy volunteers: results of a phase 2, randomized, double-blind placebo-controlled trial.sc599 vaccine is a live shigella dysenteriae 1 strain attenuated by deletion of invasion [icsa], iron chelation [ent, fep] and shiga toxin a subunit [stxa] genes. in a preliminary phase 1 single dose prospective study, we showed that sc599 vaccine was well tolerated, and the maximum tolerable dose was greater than 10(8) cfu [sadorge c, ndiaye a, beveridge n, frazer s, giemza r, jolly n, et al. phase 1 clinical trial of live attenuated shigella dysenteriae type-1 deltaicsa deltaent deltafep delta ...200919135496
trends in antimicrobial resistance of fecal shigella and salmonella isolates in tehran, iran.the resistance of bacteria to commonly prescribed antibiotics is increasing both in developing as well as developed countries. resistance has emerged even to newer, more potent antimicrobial agents. the present study was therefore undertaken to report resistance rates to antimicrobial agents in 2487 stool culture isolates in a tertiary care hospital between 1996 and 2000 and 2001 and 2005.200919136781
contribution of the periplasmic chaperone skp to efficient presentation of the autotransporter icsa on the surface of shigella flexneri.icsa is an outer membrane protein in the autotransporter family that is required for shigella flexneri pathogenesis. following its secretion through the sec translocon, icsa is incorporated into the outer membrane in a process that depends on yaet, a component of an outer membrane beta-barrel insertion machinery. we investigated the role of the periplasmic chaperone skp in icsa maturation. skp is required for the presentation of the mature amino terminus (alpha-domain) of icsa on the bacterial s ...200919047350
molecular detection of all 34 distinct o-antigen forms of shigella.shigella is the cause of shigellosis or bacillary dysentery, the occurrence of which is estimated to be 165 million cases per year worldwide, resulting in 1.1 million deaths. rapid and reliable assays for detecting and identifying shigella in food, environmental and clinical samples are therefore necessary. shigella species are traditionally identified by their o antigens. this study developed a dna microarray targeting o-serotype-specific genes to detect all 34 distinct o-antigen forms of shige ...200919074655
international foodborne outbreak of shigella sonnei infection in airline passengers.during 22-24 august 2004, an outbreak of shigella sonnei infection affected air travellers who departed from hawaii. forty-seven passengers with culture-confirmed shigellosis and 116 probable cases who travelled on 12 flights dispersed to japan, australia, 22 us states, and american samoa. all flights were served by one caterer. pulsed-field gel electrophoresis of all 29 s. sonnei isolates yielded patterns that matched within one band. food histories and menu reviews identified raw carrot served ...200918177516
antimicrobial activity of broth fermented with kefir grains.kefir grains originate from the caucasus region and are used for preparing beverages using sugar solution, milk, and fruit juice. as long as they are formed by a microbial consortium useful in the intestine, the produced drinks can be called probiotics. the aim of this study was to determine the antimicrobial activity during kefir fermentation in sugar broth. fermentations with three kinds of carbohydrates (molasses, demerara sugar, and brown sugar) as carbon source were carried out. brown sugar ...200918663417
mitracarpus frigidus aerial parts exhibited potent antimicrobial, antileishmanial, and antioxidant effects.the crude extract and the hexane, ch(2)cl(2), etoac, n-buoh, and hydromethanolic fractions of the aerial parts of mitracarpus frigidus were evaluated against promastigote forms of two species of leishmania (l. chagasi and l. amazonensis), 11 strains of bacteria (staphylococcus aureus, pseudomonas aeruginosa, salmonella enterica sorovar tythimurium, shigella sonnei, klebsiella pneumoniae, escherichia coli, micrococcus luteus, enterococcus faecalis, enterobacter cloacae, streptococcus pyogenes and ...200918644325
effect of lactoferrin on enteric pathogens.much has been learned in recent years about the mechanisms by which breastfeeding improves child health and survival. however, there has been little progress in using these insights to improve pediatric care. factors that are important for protecting the breast fed infant might be expected to decrease the adverse effects of weaning on diarrhea, growth, and development. lactoferrin, an iron-binding protein with multiple physiological functions (anti-microbial, anti-inflammatory, and immunomodulat ...200918472012
shigella species and serotypes among clinical isolates in thailand from 2001 to 2005.to study the species and the serotypes of the clinical isolates of shigella obtained from patients in thailand.200921298848
travelers' diarrhea in nepal: an update on the pathogens and antibiotic resistance.diarrhea is the most common illness among travelers and expatriates in nepal. published data on the etiology of travelers' diarrhea (td) in nepal are over 13 years old and no prior data exist on antibiotic susceptibility for currently used drugs. we investigated the etiology of diarrhea and antimicrobial susceptibility pattern of bacterial pathogens and compared the results to previous work from the same clinical setting.201021366793
sensitivity and specificity of bloody diarrhea in shigella gastroenteritis.the sensitivity and specificity of bloody diarrhea in the diagnosis of shigella gastroenteritis in a shigella sonnei prevalent center was investigated. the shigella-proven gastroenteritis cases who were admitted to hacettepe university ihsan doğramaci children's hospital diarrheal diseases unit (jan 2003 - oct 2006) constituted the study group (n=65). age- and sex-matched children admitting to the same center with non-shigella diarrhea constituted the control group (n=65). the sensitivity, speci ...201021434533
the modulation of hela cells secretory patterns by invasive shigella spp. and enteroinvasive e. coli bacterial cells and their soluble components.considering the important role of cytokines in the initiation and evolution of the inflammatory process induced by shigella and eiec strains, the purpose of this study was the characterization of the secretory patterns of hela cells induced by shigella ssp. and eiec strains and to link the obtained results with the invasiveness level of bacterial strains on this cellular line. during this study there were analyzed two eiec strains and 12 strains of the following shigella species: 2 sh. flexneri ...201021434590
enterobacteriaceae associated with eggs of podocnemis expansa and podocnemis unifilis (testudines:chelonia) in nonpolluted sites of national park of araguaia plains, brazil.fertile eggs of podocnemis expansa and podocnemis unifilis were investigated for the presence of enterobacteria, as these two endangered species have the potential for conservation measures that include egg transfer. knowledge of normal microflora associated with turtles and turtle eggs would help effectively manage the transfer of these eggs among institutions. thirty eggs of each species were collected, aseptically transferred, cracked inside plastic bags containing tetrathionate broth, and sp ...201021370647
ribonucleases and bacterial virulence.bacterial stress responses provide them the opportunity to survive hostile environments, proliferate and potentially cause diseases in humans and animals. the way in which pathogenic bacteria interact with host immune cells triggers a complicated series of events that include rapid genetic re-programming in response to the various host conditions encountered. viewed in this light, the bacterial host-cell induced stress response (hcisr) is similar to any other well-characterized environmental str ...201021375713
[shigellosis--epidemiological situation in montenegro in period 1996-2005].introduction shigellosis is the most common cause of diarrhoea in the world. it is estimated to cause 165 million cases per a year, and two third of all diseases and most of the deaths are among children under 10 years of age. the aim of this descriptive epidemiologic study was to analyze the incidence of shigellosis in montenegro during the period 1996-2005 and to find out which species of shigella were dominant in this region.201021446148
evaluation of antibacterial activity of 3-butenyl, 4-pentenyl, 2-phenylethyl, and benzyl isothiocyanate in brassica vegetables.this study investigated antibacterial activities of 4 isothiocyanates (3-butenyl, 4-phentenyl, 2-phenylethyl, and benzyl isothiocyanate) against 4 gram-positive bacteria (bacillus cereus, bacillus subtilis, listeria monocytogenes, and staphylococcus aureus) and 7 gram-negative bacteria (aeromonas hydrophila, pseudomonas aeruginosa, salmonella choleaesuis, salmonella enterica, serratia marcescens, shigella sonnei, and vibrio parahaemolyticus) by an agar disc diffusion assay. benzyl isothiocyanate ...201021535549
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