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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
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
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
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
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
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
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
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
uropathogenic escherichia coli suppresses the host inflammatory response via pathogenicity island genes sisa and sisb.extraintestinal pathogenic escherichia coli can successfully colonize the urinary tract of the immunocompetent host. in part, this is accomplished by dampening the host immune response. indeed, the sisa and sisb genes (shia-like inflammation suppressor genes a and b) of uropathogenic e. coli strain cft073, homologs of the shigella flexneri shi-2 pathogenicity island gene shia, suppress the host inflammatory response. a double deletion mutant (deltasisa deltasisb) resulted in a hyperinflammatory ...200919797063
effects of enteropathogenic bacteria & lactobacilli on chemokine secretion & toll like receptor gene expression in two human colonic epithelial cell lines.the intestinal epithelium is part of the innate immune system responding to contact with pathogenic or commensal bacteria. the objective of this study was to compare innate responses of intestinal epithelial cell lines to pathogenic bacteria and to lactobacilli.200919797815
[dysentery and amoebiasis in poland in 2007].the number as well as incidence rate of notified as shigellosis, bacillary dysentery cases in xxi century are low. only 64 cases were notified in the year 2007 (incidence rate 0.17/100,000 population), while 35 (incidence rate 0.09) were notified in 2006 and median in the 2001-2005 years was 80, incidence rate 0.21/100,000 population. since 2000 no one-death case was notified. seven imported cases were notified as they got infection being abroad, in egypt 6: 4 cases got s. flexneri, two s. sonne ...200919799247
proteome analysis of an attenuated francisella tularensis dsba mutant: identification of potential dsba substrate proteins.francisella tularensis (f. tularensis) is highly infectious for humans via aerosol route and untreated infections with the highly virulent subsp. tularensis can be fatal. our knowledge regarding key virulence determinants has increased recently but is still somewhat limited. surface proteins are potential virulence factors and therapeutic targets, and in this study, we decided to target three genes encoding putative membrane lipoproteins in f. tularensis lvs. one of the genes encoded a protein w ...200919799467
antibiotic resistance among shigella serogroups isolated in tehran, iran (2002-2004). 200919801811
autophagy in immunity against intracellular bacteria.autophagy is an innate immune defense mechanism against various intracellular bacterial pathogens, such as salmonella enterica serovar typhimurium (s. typhimurium), listeria monocytogenes and shigella flexneri. s. typhimurium uses type three secretion systems (t3sss) to invade mammalian cells and replicate in salmonella-containing vacuoles (scvs). a small population of intracellular s. typhimurium is targeted by autophagy shortly after infection. evidence suggests that these bacteria are present ...200919802566
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
microwave assisted, one-pot synthesis of 5-nitro- 2-aryl substituted-1h-benzimidazole libraries: screening in vitro for antimicrobial activity.the efficient and rapid synthesis of 5-nitro-2-aryl substituted-1h-benzimidazole libraries (1a-1j) has been established. thus, both microwave and conventional cyclo-condensation of 4-nitro ortho-phenylenediamine with various phenoxyacetic acids were carried out in the presence of hcl catalyst. the microwave synthesis route afforded advantages, such as good to excellent yields, shorter reaction time (2.5-3.5 min), readily available starting material, and simple purification procedure, which disti ...200919772484
peptide sequences identified by phage display are immunodominant functional motifs of pet and pic serine proteases secreted by escherichia coli and shigella flexneri.plasmid-encoded toxin (pet) and protein involved in colonization (pic), are serine protease autotransporters of enterobacteriaceae (spates) secreted by enteroaggregative escherichia coli (eaec), which display the gdsgsg sequence or the serine motif. our research was directed to localize functional sites in both proteins using the phage display method. from a 12mer linear and a 7mer cysteine-constrained (c7c) libraries displayed on the m13 phage piii protein we selected different mimotopes using ...200919772881
computational study of the conformational structures of saccharides in solution based on j couplings and the "fast sugar structure prediction software".this article reports on the implementation of j coupling calculations in our recently developed fast sugar structure prediction software (fsps). the fsps combines a smart and exhaustive algorithm to search through conformational space with the calculation of different experimental nuclear magnetic resonance observables to establish the conformation of saccharides in solution. using our algorithm in combination with nmr data, we investigate the solution structure of three simple disaccharides (me ...200919795837
overseas outbreaks of infectious intestinal disease identified in scotland, 2003 to 2007.this article presents information on all potential outbreaks of infectious intestinal disease (iid) identified by health protection scotland (hps) involving residents of scotland. unlike other systems, this alert system covers potential outbreaks of iid rather than apparently sporadic cases and covers all gastrointestinal pathogens, all visited countries, and all groups of travelers.200919796102
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
magnitude of drug resistant shigellosis: a report from bangalore.shigella is an important cause of acute invasive diarrhea in children and others. antimicrobial susceptibility of shigella spp. isolated from diarrhoeal/ dysenteric patients in bangalore was studied in our hospital from january 2002 to december 2007. one hundred and thirty-four isolates were identified as shigella species. s. flexneri, s. sonnei , s. boydii and s. dysenteriae were accounted respectively for 64.9%, 21.6%, 8.2% and 3.7% of the total number of shigella isolated. of these 56 (41.8%) ...200919736408
transmission risk factors and treatment of pediatric shigellosis during a large daycare center-associated outbreak of multidrug resistant shigella sonnei: implications for the management of shigellosis outbreaks among children.shigellosis outbreaks in daycare centers result in substantial disease and economic burdens in the united states. the emergence of multidrug resistant shigella strains raises questions regarding control of transmission within daycare centers and treatment for children. from may to october 2005, 639 shigella sonnei cases were reported in northwest missouri, mostly among persons exposed to daycare centers.200919738503
high-affinity inhibitors of trna-guanine transglycosylase replacing the function of a structural water cluster.the trna-modifying enzyme trna-guanine transglycosylase (tgt) is essential for the pathogenic mechanism of shigella flexneri, the causing agent of the bacterial diarrheal disease shigellosis. herein, the synthesis of a new class of rationally designed 6-amino-imidazo[4,5-g]quinazolin-8(7h)-one- (lin-benzoguanine) based inhibitors of tgt are reported. in order to accommodate a small hydrophobic crevice opening near the binding site of ribose-34, 2-aminoethyl substituents were introduced in positi ...200919746363
analysis of a temporal cluster of shigella boydii isolates in mpumalanga, south africa, november to december 2007.shigellosis is a global human health problem. the disease is most prevalent in developing countries with poor access to safe potable water and sanitation. shigella boydii is of particular epidemiological importance in developing nations such as african and asian countries. in the present study, we report on the analysis of a temporal cluster of 29 s. boydii serotype 2 strains, isolated in the mpumalanga province of south africa (sa) over the period of november to december 2007.200919749451
bcl-2 regulates the onset of shiga toxin 1-induced apoptosis in thp-1 cells.shiga toxins (stxs), which are proteins expressed by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli, are potent protein synthesis inhibitors. stx-producing organisms cause bloody diarrhea with the potential to progress to acute renal failure and central nervous system complications. studies using animal models of these diseases have shown that stxs are major virulence factors, and purified toxins have been shown to be capable of killing many types of ...200919752028
isolation of salmonella and shigella from fish harvested from the winam gulf of lake victoria, kenya.human infections caused by pathogens transmitted from fish are quite common. the aim of this study was to isolate enteric pathogenic bacteria from fish that might be transmitted to humans after the handling or consumption of such fish.200919755738
molecular characterization of esbl-producing shigella sonnei isolates from patients with bacilliary dysentery in lebanon.emergence of extended-spectrum beta-lactamases (esbls) in shigella species imparting resistance to third-generation cephalosporins is a growing concern worldwide. the aim of this study is to molecularly characterize the newly emerging beta-lactam resistant shigella sonnei, specifically esbls in lebanon, and compare them to beta-lactam sensitive isolates.200919759494
effect of iron on cytolysin a expression in salmonella enterica serovar typhi.previously, a novel protein clya (cytolysin a) has been identified in escherichia coli k-12, salmonella enterica serovars typhi and paratyphi a and shigella. salmonella spp. synthesize substantial amounts of clya upon infection of the human host, although the mechanism by which clya is induced in vivo is unclear. since environmental signals could control the expression of virulence determinants, clya expression in s. typhi ty2 was tested by western blotting in the presence of normal pooled human ...200919763423
oxidative and antibacterial activity of mn3o4.mn(3)o(4) nanoparticles with diameter ca. 10nm were synthesized by the forced hydrolysis of mn(ii) acetate at 80 degrees c. the x-ray diffraction (xrd), fourier transform infra red (ft-ir) spectroscopy, scanning electron microscopy (sem) and energy dispersive x-ray (edx) techniques were employed to study structural features and chemical composition of the nanoparticles. the unique oxidative activity of the mn(3)o(4) nanoparticles was demonstrated in the polymerization and dye degradation reactio ...200919733434
physicochemical, nutritional and antibacterial characteristics of the fruit of bromelia pinguin l.bromelia pinguin l. is a plant native to sinaloa, mexico, where its fruit is used as food or as a phytotherapeutic agent. the fruits of b. pinguin were characterized and they could be considered as a functional food. these fruits show an average weight of 13.7 g and a yellow color of high luminosity (b* = 43.2, l* = 74.5). the values for acidity (4.6%, as citric acid) and ph (3.7) of b. pinguin fruit are similar to those of citrics. the edible portion is characterized by a high content of vitami ...200919536651
increasing resistance to nalidixic acid in shigella subgroups in a comparative study between 2001-2003 and 2004-2006.the shigella spp. is an organism with an ongoing changing resistance pattern to different antibiotics, thus making its appropriate treatment difficult. nalidixic acid has been one of the most common agents used for the treatment of shigellosis. recently, some studies have reported an emerging resistance to this agent.200919710978
a novel glucosyltransferase involved in o-antigen modification of shigella flexneri serotype 1c.the o antigen of serotype 1c differs from the unmodified o antigen of serotype y by the addition of a disaccharide (two glucosyl groups) to the tetrasaccharide repeating unit. it was shown here that addition of the first glucosyl group is mediated by the previously characterized gtri cluster, which is found within a cryptic prophage at the proa locus in the bacterial chromosome. transposon mutagenesis was performed to disrupt the gene responsible for addition of the second glucosyl group, causin ...200919717593
multiplexed bead-based mesofluidic system for detection of food-borne pathogenic bacteria.in the present study, a simple and rapid multiplexed bead-based mesofluidic system (bms) was developed for simultaneous detection of food-borne pathogenic bacteria, including staphylococcus aureus, vibrio parahaemolyticus, listeria monocytogenes, salmonella, enterobacter sakazakii, shigella, escherichia coli o157:h7, and campylobacter jejuni. this system is based on utilization of isothiocyanate-modified microbeads that are 250 mum in diameter, which were immobilized with specific amino-modified ...200919717622
when shigella tells the cell to hang on.ospe, a shigella type iii effector binds to integrin-like kinase and enhances cell adhesion to better disseminate and colonize the intestinal epithelium. because of the existence of ospe orthologues in other enteropathogens such as enteropathogenic escherichia coli or salmonella sp., maintenance of cell adhesion appears as a widespread strategy for bacteria that interact with the intestinal epithelium.200919720630
assessment of cell surface properties and adhesion potential of selected probiotic strains.to evaluate the physicochemical cell surface and adhesive properties of selected probiotic strains for human use.200919725886
comparison of the entericbio multiplex pcr system with routine culture for detection of bacterial enteric pathogens.the entericbio system uses a multiplex pcr assay for the simultaneous detection of campylobacter spp., salmonella enterica, shigella spp., and escherichia coli o157 from feces. it combines overnight broth enrichment with pcr amplification and detection by hybridization. an evaluation of this system was conducted by comparing the results obtained with the system with those obtained by routine culture, supplemented with alternative pcr detection methods. in a study of 773 samples, routine culture ...200919726596
study on induction of apoptosis on hela and vero cells by recombinant shiga toxin and its subunits.verotoxin (vt) or shiga toxin (stx) produced by enterohemorrhagic escherichia coli (ehec) and shigella dysenteriae is ab5 holotoxin with potent protein synthesis inhibitor. vt can induce both apoptosis and necrosis depending on the cell type, it has been shown that vt-induced apoptosis and cytotoxicity are distinct processes, and the a subunit can be necessary for apoptosis. in other words, the precise role of each subunit in apoptosis signaling has yet to be established. in this study, inductio ...200919669659
bacterial jailbreak sounds cellular alarm: phagosome membrane remnants trigger signaling.shigella flexneri and other invasive bacteria rupture the phagosome membrane and escape to the host cytoplasm. now, dupont et al. address the fate and signaling functions of pathogen vacuole remnants and show that these membrane fragments trigger host-cell-signaling responses, including polyubiquitination, autophagy, and pyroptosis.200919683675
shigella phagocytic vacuolar membrane remnants participate in the cellular response to pathogen invasion and are regulated by autophagy.intracellular pathogens like shigella flexneri enter host cells by phagocytosis. once inside, the pathogen breaks the vacuolar membrane for cytosolic access. the fate and function of the vacuolar membrane remnants are not clear. examining shigella-infected nonmyeloid cells, we observed that proteins associated with vacuolar membrane remnants are polyubiquinated, recruit the autophagy marker lc3 and adaptor p62, and are targeted to autophagic degradation. further, inflammasome components and casp ...200919683680
a genome-scale proteomic screen identifies a role for dnak in chaperoning of polar autotransporters in shigella.autotransporters are outer membrane proteins that are widely distributed among gram-negative bacteria. like other autotransporters, the shigella autotransporter icsa, which is required for actin assembly during infection, is secreted at the bacterial pole. in the bacterial cytoplasm, icsa localizes to poles and potential cell division sites independent of the cell division protein ftsz. to identify bacterial proteins involved in the targeting of icsa to the pole in the bacterial cytoplasm, we sc ...200919684128
protective role of mouse mbl-c on intestinal mucosa during shigella flexneri invasion.mannan-binding lectin (mbl) is a c-type serum lectin, which is believed to play an important role in the innate immunity against a variety of pathogens. mbl can bind to sugar determinants of a wide variety of microorganisms, neutralize them and inhibit infection by complement activation through the lectin pathway and opsonization by collectin receptors. given that small intestine is a predominant site of extrahepatic expression of mbl, here we addressed the question whether mbl is involved in mu ...200919684159
review article: anti-inflammatory mechanisms of action of saccharomyces boulardii.saccharomyces boulardii, a well-studied probiotic, can be effective in inflammatory gastrointestinal diseases with diverse pathophysiology, such as inflammatory bowel disease (ibd), and bacterially mediated or enterotoxin-mediated diarrhoea and inflammation.200919706150
purification and characterization of an immunogenic outer membrane protein of shigella flexneri 2a.in the present study we purified 34 kda major outer membrane protein (momp) of shigella flexneri 2a for the first time, which was cross-reactive and antigenically conserved among shigella spp. and the epitope was surface exposed on the intact bacterium. the purified antigen was found to be glycosylated, which aids in binding to macrophages and up-regulated the production of nitric oxide, granulocyte-colony stimulating factor and il-12p70, indicating that the momp is immunogenic and has the abili ...200919660587
screening, purification, and identification of the enzyme producing n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester from l-isoasparagine and l-phenylalanine methyl ester.screening was carried out for microorganisms able to produce n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester [apm] from l-isoasparagine and l-phenylalanine methyl ester hydrochloride. of the 422 strains examined, 44 strains belonging to the family enterobacteriaceae were found to produce apm. the enzyme catalyzing apm production was purified and identified as dipeptidase e.200919664550
an outbreak of shigella dysenteriae in sweden, may-june 2009, with sugar snaps as the suspected source.we report an outbreak of shigella dysenteriae type 2 infections during may-june 2009 in sweden, involving 47 suspected cases of whom 35 were laboratory-confirmed. the epidemiological investigation based on interviews with the patients pointed at sugar snaps from kenya as the source. shigella was not detected in samples of sugar snaps. however, escherichia coli was confirmed in three of four samples indicating contamination by faecal material. during april to may 2009 outbreaks with shigella conn ...200919607782
nonculturable response of animal enteropathogens in the agricultural environment and implications for food safety.concerns about animal enteropathogen contamination of fresh horticultural products have,increased worldwide and are mainly due to the ability of bacteria to survive under stress conditions in the agricultural environment and during raw-vegetable processing. this review challenges the idea that the viable but nonculturable phenomenon that has been proven to occur in plant-associated environments contributes to human pathogen survival and might be correlated with foodborne infection. factors assoc ...200919610353
high frequency of hotspot mutations in core genes of escherichia coli due to short-term positive selection.core genes comprising the ubiquitous backbone of bacterial genomes are not subject to frequent horizontal transfer and generally are not thought to contribute to the adaptive evolution of bacterial pathogens. we determined, however, that at least one-third and possibly more than one-half of the core genes in escherichia coli genomes are targeted by repeated replacement substitutions in the same amino acid positions-hotspot mutations. occurrence of hotspot mutations is driven by positive selectio ...200919617543
structural insights into host gtpase isoform selection by a family of bacterial gef mimics.the escherichia coli type iii effector map belongs to a large family of bacterial virulence factors that activate host rho gtpase signaling pathways through an unknown molecular mechanism. here we report direct evidence that map functions as a potent and selective guanine-nucleotide exchange factor (gef) for cdc42. the 2.3-a structure of the map-cdc42 complex revealed that map mimics the gef strategy of the mammalian dbl family but has a three-dimensional architecture that is nearly identical to ...200919620963
[virulence factors and in vitro susceptibility of plesiomonas shigelloides isolated from diarrhea episodes in cuba].acute diarrhea is still one of the main causes of disease in developing countries. at the national reference laboratory for acute diarrhoeal diseases, of the "pedro kourí" tropical medicine institute, 54 plesiomonas shigelloides strains were serotyped. as a result, the circulation of four new serotypes (o20:h2, 056:h18, 071 :h31,081 :h22) was detected. the most common antigenic variant was 094:h3. in addition, the susceptibility pattern to 21 antimicrobial agents (aa) was studied. highest percen ...200919621156
improvement of an acid phosphatase/dhap-dependent aldolase cascade reaction by using directed evolution.to enhance the phosphorylating activity of the bacterial nonspecific acid phosphatase from salmonella enterica ser. typhimurium lt2 towards dihydroxyacetone (dha), a mutant library was generated from the native enzyme. three different variants that showed enhanced activity were identified after one round of eppcr. the single mutant v78l was the most active and showed an increase in the maximal dhap concentration to 25 % higher than that of the wild-type enzyme at ph 6.0. this variant is 17 times ...200919623595
[isolation and study of perspective probiotic strain of spore-forming bacteria from bacillus genus].to study physiologic, biochemical as well as antagonistic characteristics of isolated strain of bacillus pumilus in comparison with known spore-forming bacteria from b. subtilis species.200919623717
[etiology of acute enteric infection in children with arid zone and effect of probiotics].to study etiologic structure of acute enteric infections (aei) with isolation of hemolytic and enteropathogenic escherichia and to assess the efficacy of probiotic therapy during infections caused by e. coli.200919623719
[rapid detection of salmonella in food by using fluorescently labeled phage o-i].to develop a rapid detection method for salmonella in food by using specific salmonella-phage o-i.200919623962
an integrative approach combining noncovalent mass spectrometry, enzyme kinetics and x-ray crystallography to decipher tgt protein-protein and protein-rna interaction.the trna-modifying enzyme trna-guanine transglycosylase (tgt) is a putative target for new selective antibiotics against shigella bacteria. the formation of a tgt homodimer was suggested on the basis of several crystal structures of tgt in complex with rna. in the present study, noncovalent mass spectrometry was used (i) to confirm the dimeric oligomerization state of tgt in solution and (ii) to evidence the binding stoichiometry of the complex formed between tgt and its full-length substrate tr ...200919627989
enterohaemorrhagic escherichia coli serogroup o111 inhibits nf-(kappa)b-dependent innate responses in a manner independent of a type iii secreted ospg orthologue.enterohaemorrhagic and enteropathogenic escherichia coli (ehec and epec) inject a repertoire of effector proteins into host cells via a type iii secretion system (t3ss) encoded by the locus of enterocyte effacement (lee). ospg is an effector protein initially identified in shigella that was shown to inhibit the host innate immune response. in this study, we found ospg homologues in ehec (mainly of serogroup o111) and in yersinia enterocolitica. the t3ss encoded by the lee was able to inject thes ...200919628559
differentiation of whole bacterial cells based on high-throughput microarray chip printing and infrared microspectroscopic readout.using robotic automation, a microarray printing protocol for whole bacterial cells was developed for subsequent label-free and nondestructive infrared microspectroscopic detection. using this contact microspotting system, 24 microorganisms were printed on zinc selenide slides; these were 6 species of listeria, 10 species of vibrio, 2 strains of photobacterium damselae, yersinia enterocolitica 289, bacillus cereus atcc 14529, staphylococcus aureus, atcc 19075 (serotype 104 b), shigella sonnei 201 ...200919630511
[development of single base extension-tags microarray for the detection of food-borne pathogens].we developed single base extension-tags (sbe-tags) microarray to detect eight common food-borne pathogens, including staphylococcus aureus, vibrio parahaemolyticus, listeria monocytogenes, salmonella, enterobacter sakazaki, shigella, escherichia coli o157:h7 and campylobacter jejuni. with specific pcr primers identified and integrated for eight food-borne pathogens, target sequences were amplified and purified as template dna of single base extension-tags reaction. the products were hybridized t ...200919637631
vaccination of children in low-resource countries against shigella is unlikely to present an undue risk of reactive arthritis.shigellosis is a major cause of morbidity and mortality among children in low-resource countries. promising vaccine strategies in development include genetically attenuated shigella, killed whole cell vaccines, subcellular vaccines, and o-polysaccharide-protein conjugates. there is a concern that shigella vaccines could either induce reactive arthritis or could prime vaccinees for arthritis after a subsequent exposure to the pathogen because shigellosis is associated with reactive arthritis, esp ...200919643213
comparative study of pathogenicity tests for shigella spp. and enteroinvasive escherichia coli strains.the purpose of this study was to optimize an in vitro pathogenicity model, as an alternative to sereny test (on guinea pigs). the study was performed on 13 shigella spp. and 3 enteroinvasive escherichia coli (eiec) strains isolated in romania between 2005 and 2007. the investigation implied the comparative evaluation between the sereny test and cravioto's adapted method for the assessment of the adherence and invasion capacity of the studied bacterial strains on hela cells, as well as the pcr de ...200919507627
[norovirus infection in general hospitals for adults].to determine the role of noroviruses in the rise of hospital outbreaks of acute intestinal infections (aii), to study clinical and epidemiological aspects of hospital noroviral infection.200919514424
pulsed-field gel electrophoresis for molecular epidemiology of food pathogens.foodborne diseases due to well-recognized pathogens have emerged as an important and growing public health problem with a significant impact on health. molecular methods for subtyping these microorganisms have become a valid adjunct to the traditional techniques employed in most laboratories. one such molecular technique for the detection and identification of food pathogens is pulsed-field gel electrophoresis (pfge). this method separates large dna molecules by the use of an alternating electri ...200919521867
bacterial type iii effectors inhibit cell lifting by targeting integrin-linked kinase.many pathogenic bacteria are able to surmount exfoliation and colonize the host epithelium efficiently. in a recent article in nature, kim et al. (2009) show that shigella flexneri ospe, a conserved type iii effector, reinforces host cell adherence and prevents detachment of the infected cells by interacting with integrin-linked kinase.200919527878
sarcosaprophagous flies in suez governorate, egypt iv--persistence of human pathogenic bacteria in the developmental stages.the persistence of three species of human pathogenic bacteria (escherichia coli, shigella sonnei and staphylococcus epidermidis) in sterile artificially fed larvae was examined till adult emergence after ingestion by three species of sarcosaprophagous flies (house fly, musca domestica, oriental latrine blow fly, chrysomya megacephala and australian cheep blow fly, lucilia cuprina). the number of bacteria present in mature maggots, pupae and emerging adults declined significantly (p < 0.05). each ...200919530618
bulging fontanelle in febrile infants: is lumbar puncture mandatory?to determine the aetiologies and clinical characteristics of infants with fever and a bulging fontanelle.200919531528
[multiplex pcr assay for dissemination and diversity of extended-spectrum beta-lactamase genes in shigella isolates].to develop a rapid and simple multiplex polymerase chain reaction (pcr) method which discriminates extended-spectrum beta-lactamases (esbls) genes in sporadic shigella isolates from 1998 to 2007 in hangzhou city, china.200919534925
antibiotic resistance among bacterial pathogens in central africa: a review of the published literature between 1955 and 2008.a systematic review of the published literature on bacterial resistance in central africa between 1955 and 2008 was performed. eighty-three publications from seven countries were retrieved, the majority presenting data on enteric and other gram-negative pathogens. despite methodological limitations in many studies, alarming resistance rates are noted in nearly all pathogens. of special concern are multidrug resistance in shigella and salmonella spp. and the emergence of meticillin-resistant stap ...200919540725
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