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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
structural mimicry of o-antigen by a peptide revealed in a complex with an antibody raised against shigella flexneri serotype 2a.the use of carbohydrate-mimicking peptides to induce immune responses against surface polysaccharides of pathogenic bacteria offers a novel approach to vaccine development. factors governing antigenic and immunogenic mimicry, however, are complex and poorly understood. we have addressed this question using the anti-lipopolysaccharide monoclonal antibody f22-4, which was raised against shigella flexneri serotype 2a and shown to protect against homologous infection in a mouse model. in a previous ...200919328810
antimicrobial susceptibility and mechanisms of resistance in shigella and salmonella isolates from children under five years of age with diarrhea in rural mozambique.the antimicrobial susceptibility and mechanisms of resistance of 109 shigella and 40 salmonella isolates from children with diarrhea in southern mozambique were assessed. the susceptibility to seven antimicrobial agents was tested by disk diffusion, and mechanisms of resistance were searched by pcr or colorimetric method. a high proportion of shigella isolates were resistant to chloramphenicol (chl) (52%), ampicillin (amp) (56%), tetracycline (tet) (66%), and trimethoprim-sulfamethoxazole (sxt) ...200919332670
solar disinfection (sodis) and subsequent dark storage of salmonella typhimurium and shigella flexneri monitored by flow cytometry.pathogenic enteric bacteria are a major cause of drinking water related morbidity and mortality in developing countries. solar disinfection (sodis) is an effective means to fight this problem. in the present study, sodis of two important enteric pathogens, shigella flexneri and salmonella typhimurium, was investigated with a variety of viability indicators including cellular atp levels, efflux pump activity, glucose uptake ability, and polarization and integrity of the cytoplasmic membrane. the ...200919332832
[postinfection irritable bowel syndrome].to characterize pathogenesis, clinicolaboratory criteria and treatment of postinfection irritable bowel syndrome (pics).200919334488
expression, purification, crystallization and preliminary x-ray diffraction analysis of the tonb-dependent haem outer membrane transporter shua from shigella dysenteriae.as part of efforts towards understanding the crystallization of membrane proteins and membrane transport across the outer membrane of gram-negative bacteria, the tonb-dependent haem outer membrane transporter shua of shigella dysenteriae bound to heavy atoms was crystallized in several crystallization conditions using detergents. the insertion of a his(6) tag into an extracellular loop of shua, instead of downstream of the escherichia coli peptide signal, allowed efficient targeting to the outer ...200919342792
global etiology of travelers' diarrhea: systematic review from 1973 to the present.fifty-one published studies of travelers' diarrhea (td) were examined to look for regional differences in pathogens identified. enterotoxigenic e. coli was detected in 1,678/5,518 (30.4%) of td cases overall, with rates in latin america/caribbean (l. america), africa, south asia, and southeast asia of 1,109/3,302 (33.6%), 389/1,217 (31.2%), 153/499 (30.6%), and 36/500 (7.2%), respectively (p < 0.001). enteroaggregative e. coli was the second most common agent in l. america, found in 166/689 (24. ...200919346386
synthesis, characterization, and immunogenicity in mice of shigella sonnei o-specific oligosaccharide-core-protein conjugates.shigellosis, an enteric disease, is on the world health organization's priority prevention list. in one study, the shigella sonnei o-specific polysaccharide (o-sp)-protein conjugate showed 72% protection against disease in israeli army recruits exposed to high rates (8-14%) of infection. the protection was related to vaccine-induced igg anti-o-sp levels. synthetic oligosaccharides of shigella dysenteriae type 1, bound by their reducing ends to a carrier protein ("sun"-type configuration), induce ...200919346477
molecular characterisation of the reca locus in clinical isolates of verocytotoxigenic e. coli o157:h7.molecular epidemiology of verocytoxigenic escherichia coli o157:h7 is important to help elucidate reservoirs and modes of transmission, particularly between animals and humans. as the reca gene locus is now beginning to gain application in bacterial genotyping schemes, and as it has not been examined previously in e. coli o157 isolates, this study aims to examine potential polymorphic variation as a possible epidemiological marker for the subspecies characterisation of clinically significant ver ...200919348125
the pic protease of enteroaggregative escherichia coli promotes intestinal colonization and growth in the presence of mucin.enteroaggregative escherichia coli (eaec) is increasingly being recognized as a cause of diarrheal disease in diverse populations. no small animal model is currently available to study this pathogen. we report here that conventional mice orally inoculated with prototype eaec strain 042 generally became colonized, though the abundance of organisms cultured from their stool varied substantially among individual animals. in contrast, mice whose water contained 5 g/liter streptomycin consistently be ...200919349428
enteric bacterial pathogens in hiv-infected children with acute diarrhea in mulago referral and teaching hospital, kampala, uganda.hiv-infected children develop severe bacterial infections. we set out to determine the enteric bacterial pathogens in hiv-infected children and hiv-negative controls with acute diarrhea and their antimicrobial sensitivities.200919357426
preliminary foodnet data on the incidence of infection with pathogens transmitted commonly through food--10 states, 2008.foodborne diseases remain an important public health problem in the united states. the foodborne diseases active surveillance network (foodnet) of cdc's emerging infections program collects data from 10 u.s. states on diseases caused by enteric pathogens transmitted commonly through food. foodnet is an active, population-based surveillance system for these laboratory-confirmed infections. this report describes preliminary surveillance data for 2008 and trends since 1996. in 2008, the estimated i ...200919357633
virb alleviates h-ns repression of the icsp promoter in shigella flexneri from sites more than one kilobase upstream of the transcription start site.the icsp promoter of shigella spp. is repressed by h-ns and derepressed by virb. here, we show that an inverted repeat located between positions -1144 and -1130 relative to the icsp transcription start site is necessary for virb-dependent derepression. the atypical location of this cis-acting site is discussed.200919363111
potent bactericidal action of a flavonoid fraction isolated from the stem bark of butea frondosa.the flavonoid fraction isolated from the ethyl acetate fraction (bf-1) of butea frondosa (l.) stem bark exhibited distinct antimicrobial activity when tested against 129 bacterial strains belonging to 9 different genera of both gram-positive and gram-negative types. minimum inhibitory concentration (mic) of the fraction bf-1 was determined following nccls guidelines using the agar dilution method. twenty-four out of 36 strains of staphylococcus aureus were inhibited by 50-200 mg/l of the fractio ...200919368121
life on the inside: the intracellular lifestyle of cytosolic bacteria.bacterial pathogens exploit a huge range of niches within their hosts. many pathogens can invade non-phagocytic cells and survive within a membrane-bound compartment. however, only a small number of bacteria, including listeria monocytogenes, shigella flexneri, burkholderia pseudomallei, francisella tularensis and rickettsia spp., can gain access to and proliferate within the host cell cytosol. here, we discuss the mechanisms by which these cytosolic pathogens escape into the cytosol, obtain nut ...200919369949
mechanism of unusual formation of 3-(5-phenyl-3h-[1,2,4]dithiazol-3-yl)chromen-4-ones and 4-oxo-4h-chromene-3-carbothioic acid n-phenylamides and their antimicrobial evaluation.6/6,7-substituted 3-formylchromones (9a-e) react with 2 equivalents of 2-phenyl-4-dimethylamino-1-thia-3-azabuta-1,3-diene (10) or thiobenzamide (11) in refluxing toluene to furnish novel substituted 3-(5-phenyl-3h-[1,2,4]dithiazol-3-yl)chromen-4-ones (12a-e). however, reactions of substituted 2-anilino-3-formylchromones (15a-d) with thiobenzamide (11, 2 equivalents) in refluxing xylene furnish 4-oxo-4h-chromene-3-carbothioic acid n-phenylamide (17a-d) in high yields. a mechanistic rationalizati ...200919375826
intuitionistic fuzzy set vs. fuzzy set application in medical pattern recognition.one of the toughest challenges in medical diagnosis is uncertainty handling. the detection of intestinal bacteria such as salmonella and shigella which cause typhoid fever and dysentery, respectively, is one such challenging problem for microbiologists. they detect the bacteria by the comparison with predefined classes to find the most similar one. consequently, we observe uncertainty in determining the similarity degrees, and therefore, in the bacteria classification. in this paper, we take an ...200919375899
a new ethanolamine phosphate-containing variant of the o-antigen of shigella flexneri type 4a.the o-specific polysaccharide (o-antigen) structure of a shigella flexneri type 4a strain from the dysentery reference laboratory (london, uk) was elucidated in 1978 and its characteristic feature was found to be alpha-d-glucosylation of glcnac at position 6, which defines o-factor iv. our nmr spectroscopic studies of the o-specific polysaccharides of two other strains belonging to s. flexneri type 4a (g1668 from adelaide, australia, and 1359 from moscow, russia) confirmed the carbohydrate backb ...200919376498
[complete structure of the o-polysaccharide from shigella dysenteriae type 10].the structure of the o-specific polysaccharide from shigella dysenteriae type 10, which has been reported previously in bioorg. khim. (1977, vol. 3, pp. 1219-1225), was refined: [formula: see text].200919377533
activating mutations of n-wasp alter shigella pathogenesis.the pathogenesis of shigella requires binding to the host protein n-wasp. to examine the roles of structural conformation and phospho-regulation of n-wasp during shigella pathogenesis, mutant n-wasp constructs predicted to result in a constitutively open conformation (l229p and l232p) or either a phospho-mimicking (y253e) or phospho-disruptive (y253f) structure were constructed. pyrene actin assays demonstrated that the n-wasp l229p and l232p constructs are constitutively active. despite the inc ...200919379711
unc119 protects from shigella infection by inhibiting the abl family kinases.bacteria engage cell surface receptors and intracellular signaling molecules to enter the cell. unc119 is an adaptor protein, which interacts with receptors and tyrosine kinases. its role in bacterial invasion of cells is unknown.200919381274
role of azithromycin against clinical isolates of family enterobacteriaceae: a comparison of its minimum inhibitory concentration by three different methods.to determine the effect of azithromycin, a new azalide antibiotic, on clinical isolates of the family enterobacteriaceae and to determine and compare its minimum inhibitory concentration (mic) by disk diffusion, agar dilution and e-test methods.200919384031
altered expression of inflammatory cytokine receptors in response to lps challenge through interaction between intestinal epithelial cells and lymphocytes of peyer's patch.the intense innate immunological activities occurring at the enteric mucosal surface involve interactions between intestinal epithelial cells and immune cells. our previous studies have indicated that peyer's patch lymphocytes may modulate intestinal epithelial barrier and ion transport function in homeostasis and host defense via cell-cell contact as well as cytokine signaling. the present study was undertaken using the established co-culture system of caco-2 epithelial cells with lymphocytes o ...200919385035
inactivation of salmonella enteritidis in chicken breast fillets by single-cycle and multiple-cycle high pressure treatments.the effect of single-cycle and multiple-cycle high hydrostatic pressure (hhp) treatments on the survival of three salmonella enteritidis strains in chicken breast fillets was investigated. the surface of fillets was inoculated with a cocktail of three salmonella strains at approximately 10(7) colony-forming units (cfu)/g, and held at 4 degrees c for 20 hours before hhp treatments. reduction of salmonella counts on tryptic soy agar (tsa) by single-cycle treatments at 300 mpa and 12 degrees c rang ...200919388832
three-dimensional reconstruction of the shigella t3ss transmembrane regions reveals 12-fold symmetry and novel features throughout.type iii secretion systems (t3sss) mediate bacterial protein translocation into eukaryotic cells, a process essential for virulence of many gram-negative pathogens. they are composed of a cytoplasmic secretion machinery and a base that bridges both bacterial membranes, into which a hollow, external needle is embedded. when isolated, the latter two parts are termed the 'needle complex'. an incomplete understanding of the structure of the needle complex has hampered studies of t3ss function. to es ...200919396171
ectopic production of vapcs from enterobacteria inhibits translation and trans-activates yoeb mrna interferase.toxin-antitoxin loci have been identified in almost all free-living prokaryotes, often in high copy numbers. the biological function and molecular targets of the abundant vapbc loci are not yet known. here we analyse the vapbc loci of salmonella lt2 and shigella plasmid pmysh6000. both loci encode putative pin (pilt n-terminal) domain toxins, and antitoxins that may regulate vapbc transcription. we show that vapbc(lt2) and vapbc(pmysh) are bona fide ta loci: (i) both vapcs inhibited cell growth ...200919400780
antimicrobial activity of endemic digitalis lamarckii ivan from turkey.antimicrobial activity of the methanolic extracts of leaves and flowers of d. lamarckii ivan, (scophulariaceae), an endemic plant species of turkey, was tested on ten bacterial and four yeast strains. effective antibacterial activity was observed in four bacterial strains. minimum inhibitory concentration (mic) was calculated by use of liquid culture tests and in all the four effective bacterial strains, the mic was found to be > or = 199.5 mg/ml. the minimum bactericidal concentration (mbc) of ...200919405389
estimated burden of human salmonella, shigella, and brucella infections in jordan, 2003-2004.there is limited information on the disease burden due to foodborne pathogens in the eastern mediterranean region. this study estimates the burden of disease in jordan for salmonella, shigella, and brucella during 1 year.200919415972
rapidly fatal bacteremia caused by shigella sonnei without preceding gastrointestinal symptoms in an adult patient with lung cancer. 200919416029
synthesis, spectral characterization, in-vitro microbiological evaluation and cytotoxic activities of novel macrocyclic bis hydrazone.a macrocyclic hydrazone schiff base was synthesized by reacting 1,4-dicarbonyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol and a series of metal complexes with this new schiff base were synthesized by reaction with co(ii), ni(ii) and cu(ii) metal salts. the schiff base and its complexes have been characterized by elemental analyses, ir, (1)h nmr, uv-vis, fab mass, esr spectra, fluorescence, thermal, magnetic and molar conductance data. the analytical data reveal that the co(ii), ni(ii) ...200919419802
going round in circles: the structural biology of type iii secretion systems. 200919421157
determination of emitted airborne microorganisms from a bio-pak wastewater treatment plant.results of a study conducted to assess the degree of airborne microbial contamination generated by a wastewater treatment plant (wwtp) with bioreactor "bio-pak" closed treatment system and evaluation of the dispersion of potential pathogens are described. over the year aerosol samples were collected simultaneously with sedimentation and impact methods from several plant sites and the surroundings. external upwind sites were used as control. total colony-forming counts of heterotrophic psychrophi ...200919428042
design of alpha-transglucosidases of controlled specificity for programmed chemoenzymatic synthesis of antigenic oligosaccharides.combined with chemical synthesis, the use of biocatalysts holds great potential to open the way to novel molecular diversity. we report in vitro chemoenzymatic pathways that, for the first time, take advantage of enzyme engineering to produce complex microbial cell-surface oligosaccharides and circumvent the chemical boundaries of glycochemistry. glycoenzymes were designed to act on nonnatural conveniently protected substrates to produce intermediates compatible with a programmed chemical elonga ...200919432472
liposomes recruit ipac to the shigella flexneri type iii secretion apparatus needle as a final step in secretion induction.shigella flexneri contact with enterocytes induces a burst of protein secretion via its type iii secretion apparatus (ttsa) as an initial step in cellular invasion. we have previously reported that ipad is positioned at the ttsa needle tip (m. espina et al., infect. immuno. 74:4391-4400, 2006). from this position, ipad senses small molecules in the environment to control the presentation of ipab to the needle tip. this step occurs without type iii secretion induction or ipac recruitment to the s ...200919433542
the rho gtpase inactivation domain in vibrio cholerae martx toxin has a circularly permuted papain-like thiol protease fold.a rho gtpase inactivation domain (rid) has been discovered in the multifunctional, autoprocessing rtx toxin rtxa from vibrio cholerae. the rid domain causes actin depolymerization and rounding of host cells through inactivation of the small rho gtpases rho, rac, and cdc42. with only a few toxin proteins containing rid domains in the current sequence database, the structure and molecular mechanisms of this domain are unknown. using comparative sequence and structural analyses, we report homology ...200919434753
go4genome: a prokaryotic phylogeny based on genome organization.determining the phylogeny of closely related prokaryotes may fail in an analysis of rrna or a small set of sequences. whole-genome phylogeny utilizes the maximally available sample space. for a precise determination of genome similarity, two aspects have to be considered when developing an algorithm of whole-genome phylogeny: (1) gene order conservation is a more precise signal than gene content; and (2) when using sequence similarity, failures in identifying orthologues or the in situ replaceme ...200919436929
determination of foodborne pathogenic bacteria by multiplex pcr-microchip capillary electrophoresis with genetic algorithm-support vector regression optimization.a rapid and sensitive method based on microchip capillary electrophoresis with condition optimization of genetic algorithm-support vector regression (ga-svr) was developed and applied to simultaneous analysis of multiplex pcr products of four foodborne pathogenic bacteria. four pairs of oligonucleotide primers were designed to exclusively amplify the targeted gene of vibrio parahemolyticus, salmonella, escherichia coli (e. coli) o157:h7, shigella and the quadruplex pcr parameters were optimized. ...200919446070
international foodborne outbreak of shigella sonnei infection in airline passengers.during 22-24 august 2004, an outbreak of shigella sonnei infection affected air travellers who departed from hawaii. forty-seven passengers with culture-confirmed shigellosis and 116 probable cases who travelled on 12 flights dispersed to japan, australia, 22 us states, and american samoa. all flights were served by one caterer. pulsed-field gel electrophoresis of all 29 s. sonnei isolates yielded patterns that matched within one band. food histories and menu reviews identified raw carrot served ...200918177516
pcr targeting of antibiotic resistant bacteria in public drinking water of lahore metropolitan, pakistan.to investigate the prevalence of kanamycin (kan) and ampicillin (amp) resistant bacteria in public drinking water.200920337218
an urban, water-borne outbreak of diarrhoea and shigellosis in a district town in eastern india.in september 2007, the gayeshpur municipality reported a cluster of cases with diarrhoea. we aimed to identify the causative agent and the source of the disease.200920334044
acute gastrointestinal illness in new zealand: information from a survey of community and hospital laboratories.to describe and quantify laboratory testing of faecal samples for enteric pathogens as a component of the reporting pyramid of acute gastrointestinal illness (agi) in new zealand.200920148044
highly sensitive detection of shigella flexneri using fluorescent silica nanoparticles.robust signal amplification tactic is a good solution for improving detection sensitivity. unprocessed fluorophores have many limitations. here we describe an effective strategy for highly sensitive detection of bacteria by using fluorescent conjugated nanoparticles. the nanoparticles were synthesized using silica as matrix. fluorescein isothiocyanate distributed in the matrix. s. flexneri specific antibody was coated on the surface of the nanoparticles. compared to the traditional fluorescent a ...200920128444
[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
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
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
escherichia coli as reservoir for macrolide resistance genes.the plasmid-borne mph(a) gene that confers resistance to azithromycin and has recently emerged in shigella sonnei is present in multidrug- and non-multidrug-resistant escherichia coli isolates from 4 continents. further spread of mph(a) to shigella and salmonella spp. may be expected.200919861064
the pathogenic properties of a novel and conserved gene product, kerv, in proteobacteria.identification of novel virulence factors is essential for understanding bacterial pathogenesis and designing antibacterial strategies. in this study, we uncover such a factor, termed kerv, in proteobacteria. experiments carried out in a variety of eukaryotic host infection models revealed that the virulence of a pseudomonas aeruginosa kerv null mutant was compromised when it interacted with amoebae, plants, flies, and mice. bioinformatics analyses indicated that kerv is a hypothetical methyltra ...200919779606
genome sequences of escherichia coli b strains rel606 and bl21(de3).escherichia coli k-12 and b have been the subjects of classical experiments from which much of our understanding of molecular genetics has emerged. we present here complete genome sequences of two e. coli b strains, rel606, used in a long-term evolution experiment, and bl21(de3), widely used to express recombinant proteins. the two genomes differ in length by 72,304 bp and have 426 single base pair differences, a seemingly large difference for laboratory strains having a common ancestor within t ...200919786035
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
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