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high prevalence of ctx-m-15 extended-spectrum beta-lactamase among contacts of patients with shigellosis due to shigella flexneri carrying ctx-m-15. 200717646198
holo- and apo-bound structures of bacterial periplasmic heme-binding proteins.an essential component of heme transport in gram-negative bacterial pathogens is the periplasmic protein that shuttles heme between outer and inner membranes. we have solved the first crystal structures of two such proteins, shut from shigella dysenteriae and phut from pseudomonas aeruginosa. both share a common architecture typical of class iii periplasmic binding proteins. the heme binds in a narrow cleft between the n- and c-terminal binding domains and is coordinated by a tyr residue. a comp ...200717925389
vinculin binding in its closed conformation by a helix addition mechanism.vinculin links integrin receptors to the actin cytoskeleton by binding to talin. vinculin is held in an inactive, closed-clamp conformation through hydrophobic interactions between its head and tail domains, and vinculin activation has long been thought to be dependent upon severing the head-tail interaction. talin, alpha-actinin, and the invasin ipaa of shigella flexneri sever vinculin's head-tail interaction by inserting an alpha-helix into vinculin's n-terminal four-helical bundle, provoking ...200717932491
[serotype distribution and antimicrobial resistance rates of shigella spp. isolates in tehran, iran].in this study, antimicrobial resistance patterns and serotype distributions of shigella spp. isolated from pediatric and adult patients with diarrhea, inhabiting in tehran, were investigated. stool specimens of 1350 patients with diarrhea who were admitted to the seven different hospitals in tehran from november 2003 till march 2005 were taken into the study. antibacterial susceptibility patterns of shigella spp. isolates were determined by standard disk diffusion method. overall isolation rate ...200717933258
[viable but non-culturable form of bacteria].viable but non-culturable (vbnc) bacteria concept has been defined in 1982 when it has been shown that there exists bacteria whose metabolic activity continue and which can have the ability to reproduce in suitable conditions although they have lost their capability to reproduce in culture. recent studies have shown that most of the human pathogens (campylobacter spp., escherichia coli, francisella tularensis, helicobacter pylori, legionella pneumophila, listeria monocytogenes, mycobacterium tub ...200717933263
in vitro antimicrobial activity of rifaximin against enteropathogens causing traveler's diarrhea.the in vitro activity of rifaximin against 84 diarrheagenic escherichia coli and 11 shigella sonnei causing traveler's diarrhea was evaluated. the mic of rifaximin ranged between <0.007 and 32 mg/l; other agents tested had an mic of >256 mg/l in most cases. the results showed the potential use of rifaximin to treat these infections.200717889485
[modulation of virulence expression in escherichia coli and shigella spp. by environmental factors]. 200717891998
dynamic proteome changes of shigella flexneri 2a during transition from exponential growth to stationary phase.shigella flexneri is an infectious pathogen that causes dysentery to human, which remains a serious threat to public health, particularly in developing countries. in this study, the global protein expression patterns of s. flexneri during transition from exponential growth to stationary phase in vitro were analyzed by using 2-d page combined with maldi-tof ms. in a time-course experiment with five time points, the relative abundance of 49 protein spots varied significantly. interestingly, a puta ...200717893076
the type iii secretion system of proteus mirabilis hi4320 does not contribute to virulence in the mouse model of ascending urinary tract infection.the gram-negative enteric bacterium proteus mirabilis is a frequent cause of urinary tract infections (utis) in individuals with long-term indwelling catheters or with complicated urinary tracts. the recent release of the p. mirabilis strain hi4320 genome sequence has facilitated identification of potential virulence factors in this organism. genes appearing to encode a type iii secretion system (ttss) were found in a low gc-content pathogenicity island in the p. mirabilis chromosome. this islan ...200717893161
molecular characterization of antimicrobial compound produced by lactobacillus acidophilus aa11.approximately 63 strains of lactobacillus acidophilus were isolated from egyptian home-made cheese and examined for production of antagonism. only eight strains demonstrated inhibitory activity against spoilage microorganisms (i.e. staphylococcus aureus and bacillus cereus) and pathogens (i.e. e. coli, salmonella sp. and shigella sp.). lactobacillus acidophilus aa11 produced higher antimicrobial activity with a wide range of inhibition. the agent aa11 was sensitive to proteolytic enzymes and ret ...200717899791
an outbreak of multi-resistant shigella sonnei in australia: possible link to the outbreak of shigellosis in denmark associated with imported baby corn from thailand. 200717900420
potent inhibitors of trna-guanine transglycosylase, an enzyme linked to the pathogenicity of the shigella bacterium: charge-assisted hydrogen bonding. 200717902085
a new alpha-galactosyl-binding protein from the mushroom lyophyllum decastes.a new alpha-galactosyl binding lectin was isolated from the fruiting bodies of the mushroom lyopyllum decastes. it is a homodimer composed of noncovalently-associated monomers of molecular mass 10,276da. the lectin's amino acid sequence was determined by cloning from a cdna library using partial sequences determined by automated edman sequencing and by mass spectrometry of enzyme-derived peptides. the sequence shows no significant homology to any known protein sequence. analysis of carbohydrate ...200717904093
biochemical characterization of dtdp-d-qui4n and dtdp-d-qui4nac biosynthetic pathways in shigella dysenteriae type 7 and escherichia coli o7.o-antigen variation due to the presence of different types of sugars and sugar linkages is important for the survival of bacteria threatened by host immune systems. the o antigens of shigella dysenteriae type 7 and escherichia coli o7 contain 4-(n-acetylglycyl)amino-4,6-dideoxy-d-glucose (d-qui4nglyac) and 4-acetamido-4,6-dideoxy-d-glucose (d-qui4nac), respectively, which are sugars not often found in studied polysaccharides. in this study, we characterized the biosynthetic pathways for dtdp-d-q ...200717905981
o-antigen modal chain length in shigella flexneri 2a is growth-regulated through rfah-mediated transcriptional control of the wzy gene.shigella flexneri 2a 2457t produces lipopolysaccharide (lps) with two o-antigen (oag) chain lengths: a short (s-oag) controlled by wzzb and a very long (vl-oag) determined by wzz(phs-2). this study demonstrates that the synthesis and length distribution of the s. flexneri oag are under growth-phase-dependent regulation. quantitative electrophoretic analysis showed that the vl-oag increased during growth while the s-oag distribution remained constant. increased production of vl-oag correlated wit ...200717906147
antibacterial activity directed isolation of compounds from punica granatum.chemical investigation of the methanolic extract of pomegranate fruit following antibacterial activity directed isolation led to the isolation of pelargonidin-3-galactose, cyanidin-3-glucose, gallic acid, quercetin, and myricetin. all these compounds exhibited substantial activity against species of corynebacteria, staphylococci, streptococci, bacillus subtilis, shigella, salmonella, vibrio cholera, and escherichia coli. however, all these compounds were more active against gram-positive species ...200718034726
synthesis and evaluation of the antimicrobial activity of novel quinazolinones.a simple and efficient microwave-assisted methodology for regioselective alkylation of exocyclic nitrogen of cyclic amidines was developed and novel n-alkylated 3,4-dihydropyrazino [2,1-b] quinazolin-6-ones were prepared. although none of the molecules tested have any specific anti-quorum sensing (-qs) activity, our result validates the growth tests devised to control the bias of the anti-qs tests. among the molecules studied, compound 2b exhibits interesting activity against the gram-negative b ...200718035826
[characteristic of the etiologic structure of acute enteric infections in adults based on the data from infectious diseases hospital].study of the etiologic spectrum of sporadic cases of causative agents of acute enteric infections (aei) in 753 patients aged 15-85 years old using polymerase chain reaction (pcr) was performed in the infectious diseases hospital during 12 months. it was shown that detection of the causative agents of aei by pcr was 2.2 times more effective than routine microbiologic diagnostics supplemented with test of feces on rotavirus by elisa method and allowed to detect etiologic agent in 54.3% of the pati ...200718038539
changing patterns of antimicrobial susceptibility of shigella serotypes isolated from children with acute diarrhea in manipal, south india, a 5 year study.this study was carried out to determine the current pattern of shigella serogroups and their antimicrobial resistance in children with acute gastroenteritis in manipal, south india. a total of 1,200 stool samples were collected from april 2001 to may 2006 in children suffering from acute gastroenteritis attending the out-patient department of pediatrics at kasturba hospital, manipal, south india. these samples were cultured for enteric pathogens. the isolates were confirmed to be shigella by bio ...200718041303
environmental stress regulates shigella virulence: interplay between anerobiosis and iron acquisition. 200718041901
antibiotic resistance and resistance mechanisms in campylobacter jejuni and campylobacter coli.campylobacter jejuni and campylobacter coli are recognized as the most common causative agents of bacterial gastroenteritis in the world and infections with these organisms occur more frequently than do infections due to salmonella species, shigella species, or escherichia coli 0157:h7. the incidence of human campylobacter infections has increased markedly in both developed and developing countries worldwide and, more significantly, so has the rapid emergence of antibiotic-resistant campylobacte ...200718031331
the distribution of insertion sequences in the genome of shigella flexneri strain 2457t.shigella flexneri, which causes shigellosis in humans, evolved from escherichia coli. the sequencing of shigella genomes has revealed that a large number of insertion sequence (is) elements (over 200 elements) reside in the genome. although the presence of these elements has been noted previously and summarized, more detailed analyses are required to understand their evolutionary significance. here, the genome of s. flexneri strain 2457t is used to investigate the spatial distribution of is copi ...200718031340
antibacterial activity of some 3-(arylideneamino)-2-phenylquinazoline-4(3h)-ones: synthesis and preliminary qsar studies.synthesis of ten 3-(arylideneamino)-2-phenylquinazoline-4(3h)-ones is reported. all the compounds contained a common phenyl group at the 2-position, while the substituents on the arylideneamino group were varied. the compounds were investigated for their antimicrobial activity against both gram-positive (staphylococcus aureus 6571 and bacillus subtilis) and gram-negative bacteria (escherichia coli k12 and shigella dysenteriae 6) using a turbidometric assay method. it was found that the incorpora ...200717978766
shigella: a sexually transmitted infection in men who have sex with men. 200717983823
secretory iga mediates bacterial translocation to dendritic cells in mouse peyer's patches with restriction to mucosal compartment.in addition to fulfilling its function of immune exclusion at mucosal surfaces, secretory iga (siga) ab exhibits the striking feature to adhere selectively to m cells in the mouse and human intestinal peyer's patches (pps). subsequent uptake drives the siga ab to dendritic cells (dcs), which become partially activated. using freshly isolated mouse dcs, we found that the interaction with siga was tissue and dc subtype dependent. only dcs isolated from pps and mesenteric lymph nodes interacted wit ...200718025221
type iii secretion effectors of the ipah family are e3 ubiquitin ligases.many bacteria pathogenic for plants or animals, including shigella spp., which is responsible for shigellosis in humans, use a type iii secretion apparatus to inject effector proteins into host cells. effectors alter cell signaling and host responses induced upon infection; however, their precise biochemical activities have been elucidated in very few cases. utilizing saccharomyces cerevisiae as a surrogate host, we show that the shigella effector ipah9.8 interrupts pheromone response signaling ...200718005683
microbial pathogen-induced necrotic cell death mediated by the inflammasome components cias1/cryopyrin/nlrp3 and asc.cryopyrin (cias1, nlrp3) and asc are components of the inflammasome, a multiprotein complex required for caspase-1 activation and cytokine il-1beta production. cias1 mutations underlie autoinflammation characterized by excessive il-1beta secretion. disease-associated cryopyrin also causes a program of necrosis-like cell death in macrophages, the mechanistic details of which are unknown. we find that patient monocytes carrying disease-associated cias1 mutations exhibit excessive necrosis-like dea ...200718005730
epidemiology and clinical presentation of shigellosis in children less than five years of age in rural mozambique.rectal swabs were collected from 1354 children <5 years of age with diarrhea attending manhiça district hospital and from 227 healthy community controls. shigellosis incidence was high among children aged 12-47 months (488.4/10(5) child-years at risk). fever and dysentery were prominent clinical findings. shigella was more frequently isolated from cases than controls (6.7% versus 0.4%, p = 0.004), and from dysentery than nondysenteric diarrhea (24.1% versus 3.5%, p < 0.001). shigella flexneri 2a ...200717984817
increasing spectrum in antimicrobial resistance of shigella isolates in bangladesh: resistance to azithromycin and ceftriaxone and decreased susceptibility to ciprofloxacin.antimicrobial resistance of shigella isolates in bangladesh, during 2001-2002, was studied and compared with that of 1991-1992 to identify the changes in resistance patterns and trends. a significant increase in resistance to trimethoprim-sulphamethoxazole (from 52% to 72%, p < 0.01) and nalidixic acid (from 19% to 51%, p < 0.01) was detected. high, but unchanged, resistance to tetracycline, ampicillin, and chloramphenicol, low resistance to mecillinam (resistance 3%, intermediate 3%), and to em ...200717985817
outbreaks of shigellosis in denmark and australia associated with imported baby corn, august 2007--final summary.the recently reported concurrent outbreaks of shigella sonnei infections in denmark and australia have been found to be linked to a common baby corn packing house in thailand via trace-back of the distribution chain. distribution records indicated that three additional countries received affected product from the implicated thai packing house during the period of potential contamination. these countries were notified through the world health organization's international food safety authorities n ...200717991373
cross-border investigation of a shigella sonnei outbreak in a group of norwegian tourists after a trip to russia.in early september 2006, the norwegian institute of public health was alerted to an outbreak of shigella sonnei infections (shigellosis) among 23 norwegian passengers who had taken a bus tour from kirkenes, norway to murmansk, russia. the trip lasted from 27 to 31 august, and the group stayed in various hotels and visited several restaurants in both kirkenes and murmansk during this period. stool samples from three ill passengers yielded s. sonnei; an additional 10 passengers had gastrointestina ...200717991389
acute gastrointestinal infection, respiratory illness, and noncombat injury among us military personnel during operation bright star 2005, in northern egypt.in the fall 2005, approximately 7,500 us military personnel participated in an exercise in the egyptian desert. the epidemiology of disease and noncombat injury among deployed troops is important in the context of assessing current mitigation strategies and the development of future ones.200717995535
inactivation of shigella boydii 18 idph and listeria monocytogenes scott a with power ultrasound at different acoustic energy densities and temperatures.the effect of acoustic energy density (aed) on inactivation of shigella boydii 18 idph and listeria monocytogenes scott a in a cell suspension was studied at sublethal temperatures and at aeds of 0.49, 0.85, and 1.43 w/ml. the effect of temperature on ultrasonic inactivation of l. monocytogenes scott a at 35, 50, and 65 degrees c was examined at an aed of 1.43 w/ml. increasing aed increased the rate of inactivation for both s. boydii and l. monocytogenes. the destruction of s. boydii and l. mono ...200717995776
comparative sequence analysis of acid sensitive/resistance proteins in escherichia coli and shigella flexneri.the molecular basis for the survival of bacteria under extreme conditions in which growth is inhibited is a question of great current interest. a preliminary study was carried out to determine residue pattern conservation among the antiporters of enteric bacteria, responsible for extreme acid sensitivity especially in escherichia coli and shigella flexneri. here we found the molecular evidence that proved the relationship between e. coli and s. flexneri. multiple sequence alignment of the gadc c ...200721670792
evaluating burkholderia pseudomallei bip proteins as vaccines and bip antibodies as detection agents.burkholderia pseudomallei is a biothreat agent and an important natural pathogen, causing melioidosis in humans and animals. a type iii secretion system (ttss-3) has been shown to be critical for virulence. because ttss components from other pathogens have been used successfully as diagnostic agents and as experimental vaccines, it was investigated whether this was the case for bipb, bipc and bipd, components of b. pseudomallei's ttss-3. the sequences of bipb, bipc and bipd were found to be high ...200817995960
bacterial and fungal infections among diagnostic laboratory workers: evaluating the risks.accidental infections acquired in the laboratory environment are not reportable in a formal forum outside the institution, and therefore, there is little opportunity to evaluate such occurrences and learn from them. we evaluated voluntary responses from 88 facilities, 53 large hospitals (>200 beds) or academic institutions, 32 smaller facilities (<200 beds), and 3 national reference diagnostic laboratories. thirty-eight of the laboratories (43%), 15 large and 23 small facilities, reported no kno ...200817997259
enteropathogen resource integration center (eric): bioinformatics support for research on biodefense-relevant enterobacteria.eric, the enteropathogen resource integration center (www.ericbrc.org), is a new web portal serving as a rich source of information about enterobacteria on the niaid established list of select agents related to biodefense-diarrheagenic escherichia coli, shigella spp., salmonella spp., yersinia enterocolitica and yersinia pestis. more than 30 genomes have been completely sequenced, many more exist in draft form and additional projects are underway. these organisms are increasingly the focus of st ...200817999997
priming of cd4+ t cells with porin of shigella dysenteriae activates the cells toward type 1 polarization.macrophages treated with porin of shigella dysenteriae were potent stimulators of naive t(h) cells since the porin-pulsed macrophages strongly proliferated the t cells and up-regulated the activation molecules cd69 and cd25 on cd4(+) t cells in allogeneic mixed leukocyte reaction. immunization of c57bl/6 mice with porin selectively induced the intracellular expression and release of ifn-gamma and had no effect on il-4 expression. in parallel to the predominant release of the t(h)1 cytokine ifn-g ...200818003602
shiga toxin 1 induces apoptosis through the endoplasmic reticulum stress response in human monocytic cells.shiga toxins (stxs) expressed by the enteric pathogens shigella dysenteriae 1 and enterohaemorrhagic escherichia coli are potent protein synthesis inhibitors. shiga toxins have also been shown to induce apoptosis in epithelial, endothelial and monocytic cells. the precise relationship between protein synthesis inhibition and induction of apoptosis is not known. we show that stimulation of the myelogenous leukaemia cell line thp-1 with purified stx1 induced the endoplasmic reticulum (er) stress r ...200818005243
contribution of the sitabcd, mnth, and feob metal transporters to the virulence of avian pathogenic escherichia coli o78 strain chi7122.the roles of sitabcd, mnth, and feob metal transporters in the virulence of avian pathogenic escherichia coli (apec) o78 strain chi7122 were assessed using isogenic mutants in chicken infection models. in a single-strain infection model, compared to chi7122, the deltasit strain demonstrated reduced colonization of the lungs, liver, and spleen. complementation of the deltasit strain restored virulence. in a coinfection model, compared to the virulent apec strain, the deltasit strain demonstrated ...200818025097
the nlee/ospz family of effector proteins is required for polymorphonuclear transepithelial migration, a characteristic shared by enteropathogenic escherichia coli and shigella flexneri infections.enteropathogenic escherichia coli (epec) and shigella flexneri are human host-specific pathogens that infect intestinal epithelial cells. however, each bacterial species employs a different infection strategy within this environmental niche. epec attaches to the apical surface of small intestine enterocytes, causing microvillus effacement and rearrangement of the host cell cytoskeleton beneath adherent bacteria. in contrast, s. flexneri invades the large intestine epithelium at the basolateral m ...200817984206
saccharomyces boulardii interferes with shigella pathogenesis by postinvasion signaling events.saccharomyces boulardii is gaining in popularity as a treatment for a variety of diarrheal diseases as well as inflammatory bowel disease. this study was designed to examine the effect of this yeast on infection by shigella flexneri, a highly infectious and human host-adapted enteric pathogen. we investigated key interactions between the bacteria and host cells in the presence of the yeast in addition to a number of host responses including proinflammatory events and markers. although the presen ...200818032477
muramylpeptide shedding modulates cell sensing of shigella flexneri.bacterial infections trigger the activation of innate immunity through the interaction of pathogen-associated molecular patterns (pamps) with pattern recognition molecules (prms). the nucleotide-binding oligomerization domain (nod) proteins are intracellular prms that recognize muramylpeptides contained in peptidoglycan (pgn) of bacteria. it is still unclear how nod1 physically interacts with pgn, a structure internal to the gram-negative bacterial envelope. to contribute to the understanding of ...200818042252
identification of newly recognized serotype 1c as the most prevalent shigella flexneri serotype in northern rural vietnam.we investigated the identity of 37 shigella flexneri strains that had previously been isolated from northern rural vietnam (son tay province) and described as untypable. twenty-four isolates reacted with masf 1c, a monoclonal antibody specific for s. flexneri serotype 1c. a further ten untypable isolates were found to be rough mutants (no longer expressing o-antigen) that were derived from serotype 1c strains. pulsed-field gel electrophoresis demonstrated that these strains consisted of many dif ...200817922932
clostridium difficile: an under-recognized cause of reactive arthritis?reactive arthritis usually presents as a sterile, inflammatory, asymmetric oligoarthritis, affecting large lower extremity joints. extra-articular features (conjunctivitis, uveitis, enthesopathy, urethritis, balanitis, keratoderma blenorrhagicum) may occur. common causes of enteric reactive arthritis are preceding infections attributable to salmonella, shigella, campylobacter, and yersinia. in contrast, clostridium difficile is an uncommon cause of reactive arthritis, with only approximately 40 ...200817902012
development of a tripartite vector system for live oral immunization using a gram-negative probiotic carrier.the mucosa represents the primary target site and thus the first barrier for most microbial pathogens. nevertheless, nearly all present-day vaccines are applied by an invasive route, target the systemic immune system, and do not confer efficient mucosal protection. currently, mucosal immunity can only be achieved by the delivery of antigens via the mucosal route. therefore, multiple efforts are under way to develop mucosal vaccines and particularly live oral vaccines as these would confer consid ...200817936683
a role for nod-like receptors in autophagy induced by shigella infection.shigella infection, the cause of bacillary dysentery, induces caspase-1 activation and cell death in macrophages, but the precise mechanisms remain poorly understood. in our recent study, we presented evidence that caspase-1 activation and il-1beta processing induced by shigella are mediated through ipaf, a cytosolic pattern-recognition receptor of the nucleotide-binding oligomerization domain (nod)-like receptor (nlr) family and the adaptor protein apoptosis-associated speck-like protein contai ...200817932464
synthesis, characterization and antibacterial activity of cobalt(iii) complexes with pyridine-amide ligands.the ligands 2-(n-(x-pyridyl)carbamoyl)pyridine (x=2, 3 or 4 for hl1-hl3, respectively) and 2,6-bis(n-(y-pyridyl)carbamoyl)pyridine (y=2, 3 or 4 for h2l4-h2l6, respectively) in their mono- and di-deprotonated forms have been used to synthesize kinetically stable cobalt(iii) compounds [co(l1-3)3] (1-3) and na[co(l4-6)2] (4-6), respectively. the co(iii) ion is in octahedral environment and is surrounded by three bidentate ligands in complexes 1-3 and two tridentate ligands in complexes 4-6. ligands ...200817959275
[hemolytic and uremic syndrome in the child].hemolytic and uremic syndrome (hus) is characterized by the association of hemolytic anemia with sckizocytes, thrombopenia and renal involvement secondary to thrombotic microangiopathy. the typical form is the most frequent in children occurring after an episode of diarrhea caused by escherichia coli. other microorganisms may be responsible for hus such as shigella dysenteriae or streptococcus pneumoniae. acute renal failure is reversible in most cases, but long-term renal sequelae are seen in o ...200817964233
the pattern-recognition molecule nod1 is localized at the plasma membrane at sites of bacterial interaction.the pattern-recognition molecule nod1 is a critical sensor for bacterial derived diaminopimelic acid-containing peptidoglycan fragments which induces innate immune responses in epithelial cells. here we report the subcellular localization of this protein in human epithelial cells. nod1 is localized in the cytosol and at the plasma membrane in human cells. this membrane association is dependent on the integrity of the protein, on its signalling capacity and on an intact actin cytoskeleton. signal ...200817970764
role of shigella infection in endometriosis: a novel hypothesis.endometriosis is the presence of endometrial cells and stroma at ectopic sites outside the uterine cavity. the natural history of endometriosis is uncertain, its etiology unknown, the clinical presentation inconsistent, diagnosis difficult and the treatment poorly standardized. it causes significant morbidity due to pelvic pain and infertility among 15-25% of women during their reproductive age. the benign disease causes peritoneal inflammation, fibrosis, adhesions and ovarian cysts but displays ...200817888583
isolation and antibiotic susceptibility of salmonella and shigella strains isolated from children in gaza, palestine from 1999 to 2006.diarrhea and acute gastroenteritis are among the leading causes of illnesses and death in infants and children throughout the world, especially in developing countries, globally, salmonella and shigella remain the major contributors to acute enteric infections and diarrhea.200817854424
drastic decrease of salmonella enteritidis isolated from humans in belgium in 2005, shift in phage types and influence on foodborne outbreaks.in belgium, non-typhoidal salmonellosis and campylobacteriosis are the two most frequently reported foodborne illnesses. during 2005, a 71% decrease of salmonella enteritidis infections compared with the average annual number cases in the period 2000-2004 was recorded by the belgian national reference centre for salmonella and shigella. after the peak of 1999, the total number of salmonellosis cases decreased gradually, with the exception of 2003 when an increase was again recorded due to the ri ...200817645812
part ii. analysis of data gaps pertaining to shigella infections in low and medium human development index countries, 1984-2005.the global incidence of shigella infection has been estimated at 80-165 million episodes annually, with 99% of episodes occurring in the developing world. to identify contemporary gaps in the understanding of the global epidemiology of shigellosis, we conducted a review of the english-language scientific literature from 1984 to 2005, restricting the search to low and medium human development countries. our review yielded 11 population-based studies of shigella burden from seven countries. no pop ...200817686195
detection of the causative agent of furunculusis, aeromonas salmonicida in salmonids of the krka river.in this paper we describe the bacterial community associated with salmonids from the krka river. diversity analysis demonstrated that majority of the recovered bacteria were related to aeromonadaceae group. bacterial analysis also revealed the presence of shigella spp. and pseudomonas fluorescens. isolation of aeromonas salmonicida from trout, presents first isolation of this bacteria croatian rivers.200817624808
risk areas and neighborhood-level risk factors for shigella dysenteriae 1 and shigella flexneri.annually, there are 165 million cases of shigellosis resulting in 1.1 million deaths in the developing world. two species of the causative agent, shigella dysenteriae 1 and shigella flexneri, are responsible for acute diarrheal illness. vaccines are being developed against both but many questions remain about the disease burden, distribution of species in space and time, and community-level risk factors. this study answers two questions. what are the differences in neighborhood-level risk factor ...200817602851
analysis of bacterial dna in synovial tissue of tunisian patients with reactive and undifferentiated arthritis by broad-range pcr, cloning and sequencing.bacteria and/or their antigens have been implicated in the pathogenesis of reactive arthritis (rea). several studies have reported the presence of bacterial antigens and nucleic acids of bacteria other than those specified by diagnostic criteria for rea in joint specimens from patients with rea and various arthritides. the present study was conducted to detect any bacterial dna and identify bacterial species that are present in the synovial tissue of tunisian patients with reactive arthritis and ...200818412942
containment of tumor-colonizing bacteria by host neutrophils.administration of facultative anaerobic bacteria like salmonella typhimurium, shigella flexneri, and escherichia coli to tumor-bearing mice leads to a preferential accumulation and proliferation of the microorganisms within the solid tumor. until now, all known tumor-targeting bacteria have shown poor dissemination inside the tumors. they accumulate almost exclusively in large necrotic areas and spare a rim of viable tumor cells. interestingly, the bacteria-containing necrotic region is separate ...200818413765
development of a travelers' diarrhea vaccine for the military: how much is an ounce of prevention really worth?infectious diarrhea is one of the many threats to the deployed military, and given limited resources, a decision to pursue a vaccine acquisition strategy should be based on best evidence that weighs costs and benefits compared to alternatives. an economic model was developed to estimate the marginal cost to avert a duty day lost due to diarrhea for a vaccine acquisition strategy compared to current clinical management, for both multiplex and pathogen-specific vaccines. vaccines against campyloba ...200818417259
safety and immunogenicity of wrsd1, a live attenuated shigella dysenteriae type 1 vaccine candidate.among shigella serotypes shigella dysenteriae type 1 produces the most severe disease, including cases of hemolytic-uremic syndrome and pandemic outbreaks. wrsd1 is a live s. dysenteriae 1 strain attenuated by deletion of the virg(icsa) gene, which encodes a protein that mediates intercellular spread, and stxa and stxb, which encode the shiga toxin. in this phase i trial five groups of eight subjects ingested escalating doses of wrsd1 ranging from 10(3) to 10(7)cfu. no subject experienced fever ...200818468742
estimation of the diagnostic accuracy of the inva-gene-based pcr technique and a bacteriological culture for the detection of salmonella spp. in caecal content from slaughtered pigs using bayesian analysis.the goal of this study was to estimate the accuracy of the inva-gene-based polymerase chain reaction (pcr) and a culture technique based on pre-enrichment with buffered peptone water, three selective enrichment media (selenite, tetrathionate and rappaport-vassiliadis broths) and four selective, solid media (xylose-lysine-tergitol-4, salmonella/shigella, hekton-enteric and macconkey), for the detection of salmonella organisms from caecal samples from slaughter pigs. for this purpose a latent-clas ...200818234030
antimicrobial susceptibility of shigella isolates in eight asian countries, 2001-2004.shigellosis is a major health problem in developing countries, causing 91 million episodes and 414,000 deaths in asia annually. because of increasing trends towards drug resistance, this study was undertaken to monitor local resistance patterns of shigella isolates from 8 asian countries.200818473096
crystal structure of spa40, the specificity switch for the shigella flexneri type iii secretion system.the pathogenic bacterium shigella flexneri uses a type iii secretion system to inject virulence factors from the bacterial cytosol directly into host cells. the machinery that identifies secretion substrates and controls the export of extracellular components and effector proteins consists of several inner-membrane and cytoplasmic proteins. one of the inner membrane components, spa40, belongs to a family of proteins proposed to regulate the switching of substrate specificity of the export appara ...200818485071
specific detection of escherichia coli isolated from water samples using polymerase chain reaction targeting four genes: cytochrome bd complex, lactose permease, beta-d-glucuronidase, and beta-d-galactosidase.to develop a pcr-based method for reliable detection of escherichia coli that enables its differentiation from biochemically and phylogenetically related bacteria.200818489560
the response of type three secretion system needle proteins mxihdelta5, bsaldelta5, and prgidelta5 to temperature and ph.the type iii secretion system (ttss) is a specialized supramolecular injectisome composed of 25 or more proteins which form basal and extracellular domains and share gross architectural similarities with bacterial flagella. the extracellular component of the "needle complex" is primarily composed of a single monomeric subunit organized in a helical array surrounding a hollow pore and protrudes from the bacterial membrane. it is through this surface appendage that virulence factors are translocat ...200818491382
post-infectious functional gastrointestinal disorders in children.to investigate the development of functional gastrointestinal disorders (fgids) after an episode of acute bacterial gastroenteritis (age) in children.200818492522
enterohaemorrhagic escherichia coli and shigella dysenteriae type 1-induced haemolytic uraemic syndrome.haemolytic uraemic syndrome (hus) can be classified according to the aetiology of the different disorders from which it is composed. the most prevalent form is that induced by shigatoxin producing escherichia coli (stec) and, in some tropical regions, by shigella dysenteriae type 1. stec cause a zoonosis, are widely distributed in nature, enter the food chain in different ways, and show regional differences. not all stec are human pathogens. enterohaemorrhagic e. coli usually cause attachment an ...200818493800
fast detection of salmonella infantis with carbon nanotube field effect transistors.in this paper we report a fast, sensitive and label-free biosensor for the selective determination of salmonella infantis. it is based on a field effect transistor (fet) in which a network of single-walled carbon nantotubes (swcnts) acts as the conductor channel. anti-salmonella antibodies were adsorbed onto the swcnts and subsequently the swcnts were protected with tween 20 to prevent the non-specific binding of other bacteria or proteins. our fet devices were exposed to increasing concentratio ...200818495470
real-time pcrs and fingerprinting assays for the detection and characterization of salmonella genomic island-1 encoding multidrug resistance: application to 445 european isolates of salmonella, escherichia coli, shigella, and proteus.salmonella genomic island-1 (sgi-1) harbors a cluster of genes encoding multidrug resistance (mdr). sgi-1 is horizontally transmissible and is therefore of significant public health concern. this study presents two novel realtime pcrs detecting three sgi-1 protein-coding genes and a sgi-1 fingerprinting assay. these assays were applied to 445 european enterobacterial isolates. results from real-time pcrs were comparable to those obtained from gelbased pcrs used for the detection of sgi-1, but we ...200818500919
distinct isoforms of phospholipase a2 mediate the ability of salmonella enterica serotype typhimurium and shigella flexneri to induce the transepithelial migration of neutrophils.salmonella spp. and shigella spp. are responsible for millions of cases of enteric disease each year worldwide. while these pathogens have evolved distinct strategies for interacting with the human intestinal epithelium, they both induce significant proinflammatory responses that result in massive transepithelial migration of neutrophils across the intestinal mucosa. it has previously been shown with salmonella enterica serotype typhimurium that the process of neutrophil transmigration is mediat ...200818505810
structure and genetics of shigella o antigens.this review covers the o antigens of the 46 serotypes of shigella, but those of most shigella flexneri are variants of one basic structure, leaving 34 shigella distinct o antigens to review, together with their gene clusters. several of the structures and gene clusters are reported for the first time and this is the first such group for which structures and dna sequences have been determined for all o antigens. shigella strains are in effect escherichia coli with a specific mode of pathogenicity ...200818422615
role of rna polymerase sigma-factor (rpos) in induction of glutamate-dependent acid-resistance of escherichia albertii under anaerobic conditions.escherichia albertii is a potential enteric food-borne pathogen with poorly defined genetic and biochemical properties. acid resistance is perceived to be an important property of enteric pathogens, enabling them to survive passage through stomach acidity so that they may colonize the mammalian gastrointestinal tract. we analyzed glutamate-dependent acid-resistance pathway (gdar) in five e. albertii strains that have been identified so far. we observed that the strains were unable to induce gdar ...200818422618
comparing the antimicrobial effectiveness of nacl and kcl with a view to salt/sodium replacement.a study using a small range of pathogenic bacterial species (aeromonas hydrophila, enterobacter sakazakii, shigella flexneri, yersinia enterocolitica and 3 strains of staphylococcus aureus) has shown that potassium chloride has an equivalent antimicrobial effect on these organisms when calculated on a molar basis. combined nacl and kcl experiments were carried out and data was analysed using a modification to the lambert and lambert [lambert, r.j.w., and lambert, r., 2003. a model for the effica ...200818423764
virulent shigella flexneri subverts the host innate immune response through manipulation of antimicrobial peptide gene expression.antimicrobial factors are efficient defense components of the innate immunity, playing a crucial role in the intestinal homeostasis and protection against pathogens. in this study, we report that upon infection of polarized human intestinal cells in vitro, virulent shigella flexneri suppress transcription of several genes encoding antimicrobial cationic peptides, particularly the human beta-defensin hbd-3, which we show to be especially active against s. flexneri. this is an example of targeted ...200818426984
ctx-m-15-producing shigella sonnei strain from a czech patient who traveled in asia. 200818434554
alternative hand contamination technique to compare the activities of antimicrobial and nonantimicrobial soaps under different test conditions.antimicrobial hand soaps provide a greater bacterial reduction than nonantimicrobial soaps. however, the link between greater bacterial reduction and a reduction of disease has not been definitively demonstrated. confounding factors, such as compliance, soap volume, and wash time, may all influence the outcomes of studies. the aim of this work was to examine the effects of wash time and soap volume on the relative activities and the subsequent transfer of bacteria to inanimate objects for antimi ...200818441107
nonbloody, red stools from coadministration of cefdinir and iron-supplemented infant formulas.cefdinir is an extended-spectrum, third-generation cephalosporin that may be used for treatment of acute otitis media in patients allergic to penicillin. when administered with iron-containing products, including infant formulas, cefdinir or one of its metabolites may bind to ferric ions, forming a nonabsorbable complex that imparts a reddish color to the stool. we describe a 9-month-old infant with failure to thrive and acute otitis media who developed an erythematous maculopapular rash during ...200818447664
shigellosis: the current status of vaccine development.shigellosis, a major form of bacillary dysentery, is caused by infection with shigella organisms. in poor countries, shigella-caused dysentery is endemic and causes an estimated 163 million illness episodes annually and more than one million deaths. although several strategies have been used to develop vaccines targeting shigellosis, none has been licensed for use outside china. owing to the wide range of shigella serotypes and subtypes, there is a need for a multivalent vaccine representing pre ...200818448978
deoxycholate interacts with ipad of shigella flexneri in inducing the recruitment of ipab to the type iii secretion apparatus needle tip.type iii secretion (tts) is an essential virulence function for shigella flexneri that delivers effector proteins that are responsible for bacterial invasion of intestinal epithelial cells. the shigella tts apparatus (ttsa) consists of a basal body that spans the bacterial inner and outer membranes and a needle exposed at the pathogen surface. at the distal end of the needle is a "tip complex" composed of invasion plasmid antigen d (ipad). ipad not only regulates tts, but is required for the rec ...200818450744
a global modulatory role for the yersinia enterocolitica h-ns protein.the h-ns protein plays a significant role in the modulation of gene expression in gram-negative bacteria. whereas isolation and characterization of hns mutants in escherichia coli, salmonella and shigella represented critical steps to gain insight into the modulatory role of h-ns, it has hitherto not been possible to isolate hns mutants in yersinia. the hns mutation is considered to be deleterious in this genus. to study the modulatory role of h-ns in yersinia we circumvented hns lethality by ex ...200818451036
mutagenesis of the shigella flexneri autotransporter icsa reveals novel functional regions involved in icsa biogenesis and recruitment of host neural wiscott-aldrich syndrome protein.the icsa (virg) protein of shigella flexneri is a polarly localized, outer membrane protein that is essential for virulence. within host cells, icsa activates the host actin regulatory protein, neural wiskott-aldrich syndrome protein (n-wasp), which in turn recruits the arp2/3 complex, which nucleates host actin to form f-actin comet tails and initiate bacterial motility. linker insertion mutagenesis was undertaken to randomly introduce 5-amino-acid in-frame insertions within icsa. forty-seven l ...200818456802
what's the point of the type iii secretion system needle?recent work by several groups has significantly expanded our knowledge of the structure, regulation of assembly, and function of components of the extracellular portion of the type iii secretion system (t3ss) of gram-negative bacteria. this perspective presents a structure-informed analysis of functional data and discusses three nonmutually exclusive models of how a key aspect of t3ss biology, the sensing of host cells, may be performed.200818458349
global epidemiology of infections due to shigella, salmonella serotype typhi, and enterotoxigenic escherichia coli. 200818461719
an intersubunit active site between supercoiled parallel beta helices in the trimeric tailspike endorhamnosidase of shigella flexneri phage sf6.sf6 belongs to the podoviridae family of temperate bacteriophages that infect gram-negative bacteria by insertion of their double-stranded dna. they attach to their hosts specifically via their tailspike proteins. the 1.25 a crystal structure of shigella phage sf6 tailspike protein (sf6 tsp) reveals a conserved architecture with a central, right-handed beta helix. in the trimer of sf6 tsp, the parallel beta helices form a left-handed, coiled-beta coil with a pitch of 340 a. the c-terminal domain ...200818462681
immunological evidence for functional rather than structural mimicry by a shigella flexneri y polysaccharide-mimetic peptide.an approach to vaccine design is the use of molecules that mimic the immunogenic element of interest. in this context, the interaction of mdwnmhaa, a peptide mimic of the shigella flexneri y o polysaccharide (ps), with an anti-carbohydrate monoclonal antibody, as studied previously by x-ray crystallography, suggested the presence of functional rather than structural mimicry and a bound peptide conformation that was not represented significantly in the free-ligand ensemble. the antibody response ...200818463226
simple sequence repeats in different genome sequences of shigella and comparison with high gc and at-rich genomes.simple sequence repeats (ssrs) are omnipresent in prokaryotes and eukaryotes, and are found anywhere in the genome in both protein encoding and noncoding regions. in present study the whole genome sequences of seven chromosomes (shigella flexneri 2a str301 and 2457t, shigella sonnei, escherichia coli k12, mycobacterium tuberculosis, mycobacterium leprae and staphylococcus saprophyticus) have downloaded from the genbank database for identifying abundance, distribution and composition of ssrs and ...200818464038
insecticidal properties and microbial contaminants in a spodoptera exigua multiple nucleopolyhedrovirus (baculoviridae) formulation stored at different temperatures.the spodoptera exigua (hübner) multiple nucleopolyhedrovirus (semnpv) is currently being tested as a biological insecticide for use in greenhouse crops in southern spain. we performed a study in which semipurified semnpv occlusion bodies (obs) were formulated in phosphate-buffered saline, ph 6.5, with 5% (vol:vol) glycerol and 0.15% (wt:vol) sorbic acid, and they were stored at -20, 4, or 25 degrees c during 18 mo. initial aerobic counts (+/-se) averaged 1.4 (+/-0.17) x 10(7) colony-forming unit ...200818330114
subversion of actin dynamics by espm effectors of attaching and effacing bacterial pathogens.rho gtpases are common targets of bacterial toxins and type iii secretion system effectors. ipgb1 and ipgb2 of shigella and map of enteropathogenic (epec) and enterohemorrhagic (ehec) escherichia coli were recently grouped together on the basis that they share a conserved wxxxe motif. in this study, we characterized six wxxxe effectors from attaching and effacing pathogens: trca and espm1 of epec strain b171, espm1 and espm2 of ehec strain sakai and espm2 and espm3 of citrobacter rodentium. we s ...200818331467
prevalence of gastrointestinal bacterial pathogens in a population of zoo animals.faecal prevalence of gastrointestinal bacterial pathogens, including campylobacter, escherichia coli o157:h7, salmonella, shigella, yersinia, as well as arcobacter, were examined in 317 faecal specimens from 44 animal species in belfast zoological gardens, during july-september 2006. thermophilic campylobacters including campylobacter jejuni, campylobacter coli and campylobacter lari, were the most frequently isolated pathogens, where members of this genus were isolated from 11 animal species (1 ...200818331520
delivery of biologically active anti-inflammatory cytokines il-10 and il-1ra in vivo by the shigella type iii secretion apparatus.pathogenicity of many gram-negative bacteria relies on a type iii secretion (t3s) apparatus, which is used for delivery of bacterial effectors into the host cell cytoplasm allowing the bacteria to manipulate host cell cytoskeleton network as well as to interfere with intracellular signaling pathways. in this study, we investigated the potential of the shigella flexneri t3sa as an in vivo delivery system for biologically active molecules such as cytokines. the anti-inflammatory cytokines il-10 an ...200818322242
impact of infections and normal flora in nonhuman primates on drug development.preclinical safety studies that are required for the marketing approval of a pharmaceutical include single and repeat dose studies in rodent and nonrodent species. the use of nonhuman primates (nhps), primarily macaques, as the nonrodent species has increased in recent years, in part due to the increase in development of biopharmaceuticals and immunomodulatory agents. depending on the source of the macaques, they may vary in genetic background, normal flora, and/or the incidence of preexisting p ...200818323580
pyrosequencing analysis of the gyrb gene to differentiate bacteria responsible for diarrheal diseases.pathogens causing acute diarrhea include a large variety of species from enterobacteriaceae and vibrionaceae. a method based on pyrosequencing was used here to differentiate bacteria commonly associated with diarrhea in china; the method is targeted to a partial amplicon of the gyrb gene, which encodes the b subunit of dna gyrase. twenty-eight specific polymorphic positions were identified from sequence alignment of a large sequence dataset and targeted using 17 sequencing primers. of 95 isolate ...200818324428
cmy-2-type plasmid-mediated ampc beta-lactamase finally emerging in argentina. 200818242960
on-line monitoring of microbial volatile metabolites by proton transfer reaction-mass spectrometry.a method for analysis of volatile organic compounds (vocs) from microbial cultures was established using proton transfer reaction-mass spectrometry (ptr-ms). a newly developed sampling system was coupled to a ptr-ms instrument to allow on-line monitoring of vocs in the dynamic headspaces of microbial cultures. the novel ptr-ms method was evaluated for four reference organisms: escherichia coli, shigella flexneri, salmonella enterica, and candida tropicalis. headspace vocs in sampling bottles con ...200818245241
eukaryotic expression and antimicrobial spectrum determination of the peptide tachyplesin ii.ta0-a, the gene encoding the mature antimicrobial peptide tachyplesin ii, was engineered to optimize the coding sequence according to codon usage bias in yeast. ta0-a was efficiently expressed in the methylotrophic yeast pichia pastoris strain smd1168. the recombinant peptide ta0 reached 150mg/l after methanol induction for 6 d. ta0 was rapidly purified to homogeneity by a single step of size-exclusion chromatography. the minimal lethal concentrations of ta0 to the escherichia coli strain k12 wa ...200818249136
traveler's myopericarditis.colitis caused by shigella is an uncommon etiology of infectious diarrhea in developed countries, usually presenting as traveler's diarrhea. aside from clinical intestinal manifestations, shigellosis can present with a wide variety of extra-intestinal symptoms. we present the case of a 38-year-old man with diarrhea, fever, and chest pain that started after a holiday in cape verde (africa). blood samples revealed an increase in cardiac enzymes. an electrocardiogram revealed a widespread elevation ...200818249314
regulation of expression and secretion of nleh, a new non-locus of enterocyte effacement-encoded effector in citrobacter rodentium.together with enterohemorrhagic escherichia coli and enteropathogenic escherichia coli, citrobacter rodentium is a member of the attaching-and-effacing (a/e) family of bacterial pathogens. a/e pathogens use a type iii secretion system (t3ss) to translocate an assortment of effector proteins, encoded both within and outside the locus of enterocyte effacement (lee), into the colonized host cell, leading to the formation of a/e lesions and disease. here we report the identification and characteriza ...200818223087
the origin of a novel gene through overprinting in escherichia coli.overlapped genes originate by a) loss of a stop codon among contiguous genes coded in different frames; b) shift to an upstream initiation codon of one of the contiguous genes; or c) by overprinting, whereby a novel open reading frame originates through point mutation inside an existing gene. although overlapped genes are common in viruses, it is not clear whether overprinting has led to new genes in prokaryotes.200818226237
nlrx1 is a mitochondrial nod-like receptor that amplifies nf-kappab and jnk pathways by inducing reactive oxygen species production.nod-like receptors (nlrs) are a family of intracellular sensors of microbial- or danger-associated molecular patterns. here, we report the identification of nlrx1, which is a new member of the nlr family that localizes to the mitochondria. nlrx1 alone failed to trigger most of the common signalling pathways, including nuclear factor-kappab (nf)-kappab- and type i interferon-dependent cascades, but could potently trigger the generation of reactive oxygen species (ros). importantly, nlrx1 synergis ...200818219313
cold shock exoribonuclease r (vacb) is involved in aeromonas hydrophila pathogenesis.in this study, we cloned and sequenced a virulence-associated gene (vacb) from a clinical isolate ssu of aeromonas hydrophila. we identified this gene based on our recently annotated genome sequence of the environmental isolate atcc 7966(t) of a. hydrophila and the vacb gene of shigella flexneri. the a. hydrophila vacb protein contained 798 amino acid residues, had a molecular mass of 90.5 kda, and exhibited an exoribonuclease (rnase r) activity. the rnase r of a. hydrophila was a cold-shock pro ...200818344363
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