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metabolic control through ornithine and uracil of epithelial cell invasion by shigella flexneri.this paper shows that compounds in defined growth media strongly influence the expression of the effectors of virulence in the human invasive pathogen shigella flexneri. ornithine in conjunction with uracil reduces the haemolytic ability of wild-type cultures more than 20-fold and the expression of the type iii secretion system more than 8-fold, as monitored by an mxic : : lacz transcriptional reporter. mxic gene expression is further decreased by the presence of methionine or branched-chain ami ...200919460819
design, synthesis, and immunochemical characterization of a chimeric glycopeptide corresponding to the shigella flexneri y o-polysaccharide and its peptide mimic mdwnmhaa.two glycopeptide chimeras corresponding to the shigella flexneri y o-polysaccharide and its peptide mimic were designed in an attempt to improve the binding affinity by increasing the entropy of binding relative to the original octapeptide mimic of the o-polysaccharide. the design was based on the x-ray crystal structures of a monoclonal antibody sya/j6 in complex with its cognate ligands, a pentasaccharide corresponding to the s. flexneri y o-polysaccharide and the octapeptide mimic, mdwnmhaa. ...200919467535
rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method.to develop a new, rapid and accurate reverse dot blot (rdb) method for the detection of intestinal pathogens in fecal samples.200919469006
incidence of multiple antibiotic resistant gram-negative bacteria isolated from surface and underground water sources in south western region of nigeria.in most rural and urban settlements, particularly in nigeria, wells, spring, streams or rivers and lakes serves as major sources of water supply for drinking and other domestic purposes. unfortunately, many of the available water sources are not potable without some form of treatment which is seldom available in most settings. the use of untreated surface water sources for drinking and for domestic purposes remains a major threat to public health as these could serve as reservoirs the for transf ...200919474486
involvement of rna-binding protein hfq in the osmotic-response regulation of inve gene expression in shigella sonnei.the expression of type iii secretion system (ttss) in shigella is regulated in response to changes in environmental osmolarity and temperature. temperature-dependent regulation of virf, the master regulator of ttss synthesis, is believed to occur at the transcriptional level. we recently demonstrated, however, that ttss synthesis also involves post-transcriptional regulation of the synthesis of inve, a target of virf and key regulator of ttss synthesis. the mrna levels of inve (virb) are stable ...200919476612
ipab-ipgc interaction defines binding motif for type iii secretion translocator.the delivery of virulence factors into host cells through type iii secretion systems is essential for enterobacterial pathogenesis. molecular chaperones bind specifically to virulence factors in the bacterial cytosol before secretion. invasion plasmid gene c (ipgc) is a chaperone that binds 2 essential virulence factors of shigella: invasion plasmid antigens (ipa) b and c. here, we report the crystal structure of ipgc alone and in complex with the chaperone binding domain (cbd) of ipab. the chap ...200919478065
comparison of acute bloody and watery diarrhea: a case control study.the clinical and laboratory findings of 290 cases of bloody diarrhea who presented to the department of diarrhea training and treatment between june 1998 and may 2002 were investigated, and compared to those of two consecutive cases who had watery diarrhea. the bloody diarrhea group had higher mean age, higher frequencies of diarrhea, lower frequencies of vomiting, and shorter durations of diarrhea at the time of admission as compared to the watery diarrhea group. the number of cases using antib ...200919480324
laboratory-acquired infections.laboratory-acquired infections due to a wide variety of bacteria, viruses, fungi, and parasites have been described. although the precise risk of infection after an exposure remains poorly defined, surveys of laboratory-acquired infections suggest that brucella species, shigella species, salmonella species, mycobacterium tuberculosis, and neisseria meningitidis are the most common causes. infections due to the bloodborne pathogens (hepatitis b virus, hepatitis c virus, and human immunodeficiency ...200919480580
reactive arthritis: clinical aspects and medical management.reactive arthritis (rea) is an inflammatory arthritis that arises after certain gastrointestinal or genitourinary infections, representing a classic interplay between host and environment. it belongs to the group of arthritidies known as the spondyloarthropathies. the classic syndrome is a triad of symptoms, including the urethra, conjunctiva, and synovium; however, the majority of patients do not present with this triad. diagnostic criteria for rea exist, but data suggest new criteria are neede ...200919480995
analytical comparison of nine pcr primer sets designed to detect the presence of escherichia coli/shigella in water samples.the analytical performance of 9 different pcr primer sets designed to detect escherichia coli and shigella in water has been evaluated in terms of ubiquity, specificity, and analytical detection limit. of the 9 pcr primer sets tested, only 3 of the 5 primer sets targeting uida gene and the primer set targeting tuf gene amplified dna from all e. coli strains tested. however, of those 4 primer sets, only the primer set targeting the tuf gene also amplified dna from all shigella strains tested. for ...200919482328
protein interaction platforms: visualization of interacting proteins in yeast.here we describe the protein interaction platform assay, a method for identifying interacting proteins in saccharomyces cerevisiae. this assay relies on the reovirus scaffolding protein microns, which forms large focal inclusions in living cells. when a query protein is fused to microns and potential interaction partners are fused to a fluorescent reporter, interactors can be identified by screening for yeast that display fluorescent foci.200919483691
lack of antimicrobial activity by the antiretroviral drug nevirapine against common bacterial pathogens. 200919487448
bacteria hijack integrin-linked kinase to stabilize focal adhesions and block cell detachment.the rapid turnover and exfoliation of mucosal epithelial cells provides an innate defence system against bacterial infection. nevertheless, many pathogenic bacteria, including shigella, are able to surmount exfoliation and colonize the epithelium efficiently. here we show that the shigella flexneri effector ospe (consisting of ospe1 and ospe2 proteins), which is highly conserved among enteropathogenic escherichia coli, enterohaemorrhagic e. coli, citrobacter rodentium and salmonella strains, rei ...200919489119
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
fungal and bacterial killing by neutrophils.neutrophils are professional phagocytes of the innate immune system that are essential to control bacterial and fungal infections. these cells engulf and kill invading microbes. additionally, activated neutrophils are able to release neutrophil extracellular traps (nets). these fibers consist of chromatin decorated with antimicrobial proteins to trap and kill microbes. appropriate quantitative methods are required to understand the nature of interactions of neutrophils with pathogens. here we pr ...200919089391
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
functions and pathologies of bip and its interaction partners.the endoplasmic reticulum (er) is involved in a variety of essential and interconnected processes in human cells, including protein biogenesis, signal transduction, and calcium homeostasis. the central player in all these processes is the er-lumenal polypeptide chain binding protein bip that acts as a molecular chaperone. bip belongs to the heat shock protein 70 (hsp70) family and crucially depends on a number of interaction partners, including co-chaperones, nucleotide exchange factors, and sig ...200919151922
overexpression, purification, characterization and preliminary crystallographic study of phosphoglycolate phosphatase from shigella flexneri 2a strain 301.phosphoglycolate phosphatase has a salvage function in the metabolism of the 2-phosphoglycolate formed during bacterial dna repair. in order to better understand its dimerization behaviour, the influence of metal ions on its activity and its catalytic mechanism at the molecular level, recombinant phosphoglycolate phosphatase from shigella flexneri was overexpressed, purified, characterized and crystallized by the hanging-drop vapour-diffusion method at 291 k using polyethylene glycol 3500 as a p ...200919153451
simultaneous detection of multifood-borne pathogenic bacteria based on functionalized quantum dots coupled with immunomagnetic separation in food samples.this paper reports a method that simultaneously detects three food-borne pathogenic bacteria, salmonella typhimurium, shigella flexneri, and escherichia coli o157:h7, via an approach that combines magnetic microparticles for the enrichment and antibody-conjugated semiconductor quantum dots (qds) as fluorescence markers. using the water-in-oil reverse microemulsions method, the gamma-fe(2)o(3) magnetic nanoparticles were coated with silica to empower the particles with high dispersibility and bro ...200919154162
shigella type iii secretion effectors: how, where, when, for what purposes?bacteria of shigella spp., the causative agents of shigellosis in humans, possess a repertoire of approximately 25-30 effectors injected into host cells by a type iii secretion apparatus (t3sa). the t3sa activity is activated upon contact of bacteria with cells and controls expression of some effectors. recent structural and functional studies suggest that two different sets of effectors are involved in inducing actin cytoskeleton reorganization to promote entry of bacteria into epithelial cells ...200919157960
rapid dna amplification using a battery-powered thin-film resistive thermocycler.a prototype handheld, compact, rapid thermocycler was developed for multiplex analysis of nucleic acids in an inexpensive, portable configuration. instead of the commonly used peltier heating/cooling element, electric thin-film resistive heater and a miniature fan enable rapid heating and cooling of glass capillaries leading to a simple, low-cost thin-film resistive thermocycler (tfrt). computer-based pulse width modulation control yields heating rates of 6-7 k/s and cooling rates of 5 k/s. the ...200919159110
organised genome dynamics in the escherichia coli species results in highly diverse adaptive paths.the escherichia coli species represents one of the best-studied model organisms, but also encompasses a variety of commensal and pathogenic strains that diversify by high rates of genetic change. we uniformly (re-) annotated the genomes of 20 commensal and pathogenic e. coli strains and one strain of e. fergusonii (the closest e. coli related species), including seven that we sequenced to completion. within the approximately 18,000 families of orthologous genes, we found approximately 2,000 comm ...200919165319
the ipac carboxyterminal effector domain mediates src-dependent actin polymerization during shigella invasion of epithelial cells.shigella, the causative agent of bacillary dysentery, invades epithelial cells by locally reorganizing the actin cytoskeleton. shigella invasion requires actin polymerization dependent on the src tyrosine kinase and a functional bacterial type iii secretion (t3s) apparatus. using dynamic as well as immunofluorescence microscopy, we show that the t3s translocon component ipac allows the recruitment of the src kinase required for actin polymerization at bacterial entry sites during the initial sta ...200919165331
phage-mediated shiga toxin 2 gene transfer in food and water.shiga toxin (stx) transduction in various food matrices has been evaluated with lysogens of stx phages. stx transduction events were observed for many phages under appropriate conditions. transduction did not occur at low ph and low temperatures. a total of 10(3) to 10(4) cfu ml(-1) was the minimal amount of donor and recipient strains necessary to generate transductants.200919168651
short report: high prevalence of serine protease autotransporter cytotoxins among strains of enteroaggregative escherichia coli.enteroaggregative escherichia coli (eaec) pathogenesis is thought to comprise intestinal colonization followed by the release of enterotoxins and cytotoxins. here, we use a polymerase chain reaction (pcr) to determine the prevalence of 10 genes encoding serine protease autotransporter toxins (spates) in a collection of clinical eaec isolates. eighty-six percent of eaec strains harbored genes encoding one or more class i cytotoxic spate proteins (pet, sat, espp, or siga). two class ii, non-cytoto ...200919190229
molecular epidemiological characteristics of shigella spp. isolated from river narmada during 2005-2006.shigellosis is an acute gastroenteritis caused by shigella species. forty isolates of shigella spp. were obtained from the river narmada during 2005-2006. twenty-three isolates were identified as s. flexneri, 10 as s. sonnei, and seven as s. dysenteriae on the basis of biochemical tests and serotyping. all the isolates harbored at least one plasmid (range: 1-4) and exhibited 12 distinct plasmid profile patterns. out of 40 isolates, 90% were found to be resistant against more than two antibiotics ...200919192746
crystal structure analysis and in silico pka calculations suggest strong pka shifts of ligands as driving force for high-affinity binding to tgt.a novel ligand series is presented to inhibit trna-guanine transglycosylase (tgt), a protein with a significant role in the pathogenicity mechanism of shigella flexneri, the causative agent of shigellosis. the enzyme exchanges guanine in the wobble position of trna(asn,asp,his,tyr) against a modified base. to prevent the base-exchange reaction, several series of inhibitors have already been designed, synthesized, and tested. one aim of previous studies was to address a hydrophobic pocket with di ...200919199329
streptococcus-, shigella-, and listeria-induced autophagy.autophagy has recently been described as an intrinsic host defense system for recognizing and eliminating intracellular-invading bacterial pathogens. some cytoplasmic-invading bacteria are trapped through the process of autophagy and are ultimately degraded within autolysosomal compartments. however, others exhibit highly evolved maneuvers for circumventing autophagic recognition and are capable of surviving and replicating within the cytoplasm. in this chapter, we describe bacterial infectious ...200919200893
a synthetic carbohydrate-protein conjugate vaccine candidate against shigella flexneri 2a infection.the protective ag of shigella, the gram-negative enteroinvasive bacterium causing bacillary dysentery, or shigellosis, is its o-specific polysaccharide (o-sp) domain of the lps, the major bacterial surface component. as an alternative to the development of detoxified lps-based conjugate vaccines, recent effort was put into the investigation of neoglycoproteins encompassing synthetic oligosaccharides mimicking the protective ags of the o-sp. we previously reported that when coupled to tetanus tox ...200919201878
development of prophylactic recombinant hpv58-attenuated shigella live vector vaccine and evaluation of its protective efficacy and immunogenicity in the guinea pig keratoconjunctivitis model.to develop a prophylactic recombinant hpv58l1-attenuated shigella live vector vaccine and evaluate its protective efficacy and immunogenicity in the guinea pig keratoconjunctivitis model, the hpv58l1 gene was cloned into vector pucmt, and then subcloned into the suicide vector pcvd442. the recombinant plasmid pcvd442-hpv58l1 was introduced into attenuated shigella (sf301:deltavirg) with the helper plasmid prk2013 by filter mating. the positive colonies were harvested and confirmed by polymerase ...200919204831
[etiological analysis of enteric infectious diseases during beijing olympic games].to understand pathogen patterns of enteric infectious diseases and its impact on this pattern due to aggregation of a great deal of foreign visitors during beijing olympic games.200920137562
[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
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
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
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
diarrhea associated hemolytic uremic syndrome: a 3-year picu experience from nepal. 200920072865
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
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
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
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
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
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
[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
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
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
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
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
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