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global analysis of a plasmid-cured shigella flexneri strain: new insights into the interaction between the chromosome and a virulence plasmid.shigella flexneri is an important human pathogen that causes dysentery, and remains a significant threat to public health, particularly in developing countries. the virulence of this pathogen is dependent on an acquired virulence plasmid. to investigate the crosstalk between the bacterial chromosome and the exogenous virulence plasmid, a virulence plasmid-cured strain was constructed using plasmid incompatibility. the global patterns of gene expression of this strain compared with the wild-type ...201020000779
antibiotic therapy for shigella dysentery.shigella dysentery is a relatively common illness and occasionally causes death, worldwide. mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. the antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects.201020091606
pivotal advance: bifidobacteria and gram-negative bacteria differentially influence immune responses in the proinflammatory milieu of celiac disease.cd is a chronic inflammatory disorder of the small intestine that presents in genetically predisposed individuals following gluten consumption. in this study, the effects of bifidobacterium (bifidobacterium bifidum iata-es2 and bifidobacterium longum atcc15707) and gram-negative bacteria (bacteroides fragilis dsm2451, escherichia coli cbl2, and shigella cbd8 isolated from cd patients), alone and in the presence of cd triggers (gliadins and/or ifn-gamma) on surface marker expression and cytokine ...201020007908
reactive arthritis after enteric infections in the united states: the problem of definition.bacterial enteric infections cause substantial morbidity in the united states both from acute illness and sequelae that follow. reactive arthritis (rea) is a poorly defined term that is used to describe a variety of rheumatologic phenomena that may occur after salmonella, shigella, campylobacter, and yersinia infection, as well as other types of infections (eg, chlamydia). this review focuses on clinical and epidemiologic investigations of rea following bacterial enteric infection in the united ...201020025528
transcriptional profile of the shigella flexneri response to an alkaloid: berberine.berberine, a natural isoquinoline alkaloid found in many medicinal herbs, has been shown to be active against a variety of microbial infections. to examine the potential effects of berberine on shigella flexneri, a whole-genome dna microarray was constructed and a transcriptome analysis of the cellular responses of s. flexneri when exposed to berberine chloride (bc) was performed. our data revealed that bc upregulated a group of genes involved in dna replication, repair and division. intriguingl ...201020030725
extended-spectrum beta-lactamase-producing escherichia coli in patients with travellers' diarrhoea.the identification of patients carrying extended-spectrum beta-lactamase (esbl)-producing bacteria is important, since these patients are at risk of receiving inappropriate empirical therapy if they become infected. the purpose of this study was to investigate the occurrence of esbl-producing bacteria in patients with travellers' diarrhoea. patients with travellers' diarrhoea (n = 242) having delivered stool samples for the diagnosis of salmonella, shigella, yersinia or campylobacter, were also ...201020121649
campylobacteriosis and other bacterial gastrointestinal diseases in sofia, bulgaria for the period 1987-2008.campylobacter is the most commonly reported enteric bacterial pathogen in humans. we still do not have any systematic data concerning campylobacteriosis in bulgaria. for that reason, we present data of the thermophilic campylobacter jejuni and campylobacter coli in the aetiology of diarrhoeal diseases in sofia, for the period from 1987 to 2008. the study included patients from 0 to over 65 years-old. a total of 51,607 faecal specimens were screened for campylobacter. c. jejuni and c. coli were d ...201020122383
antibodies against recombinant shiga toxin subunit b neutralize shiga toxin toxicity in hela cells.shigella dysenteriae type 1 and escherichia coli o157:h7 produce shiga toxin 1 (stx) and shiga toxin1 (stx1), respectively and these two toxins are almost identical. e. coli o157:h7 is the major cause of diarrhea-associated hemolytic uremic syndrome. stx and stx1 are ab5 type of toxin with a molecular weight of 70 kda, comprising an enzymaticaly-active a subunit (32 kda) and five receptor-binding b subunits (7.7 kda). in this study dna fragment (289 bp, gene bank accn no. ef685161) coding for b ...201020044923
antilisterial activity of a broad-spectrum bacteriocin, enterocin lr/6 from enterococcus faecium lr/6.enterocin lr/6, a purified bacteriocin, exhibited broad inhibitory spectrum both against related as well as some food-borne pathogens such as listeria monocytogenes, yersinia enterocolitica, aeromonas sp., shigella sp., and bacillus licheniformis. in this investigation, we have focused on l. monocytogenes as the target organism, as it is not only an important pathogen but can also survive over a wide range of environmental conditions such as refrigeration temperature, low ph, and high-salt conce ...201019957209
identification of antibacterial and antifungal pharmacophore sites for potent bacteria and fungi inhibition: indolenyl sulfonamide derivatives.synthesis of seven new indolenyl sulfonamides, have been prepared by the condensation reaction of indole-3-carboxaldehyde with different sulfonamides such as, sulphanilamide, sulfaguanidine, sulfathiazole, sulfamethoxazole, sulfisoxazole, sulfadiazine and sulfamethazine. these synthesized compounds have been used as potential ligands for complexation with some selective divalent transition metal ions (cobalt, copper, nickel & zinc). structure of the synthesized ligands has been deduced from thei ...201020005022
antibacterial activity of artemisia nilagirica leaf extracts against clinical and phytopathogenic bacteria.the six organic solvent extracts of artemisia nilagirica were screened for the potential antimicrobial activity against phytopathogens and clinically important standard reference bacterial strains.201020109237
emergence of a new multidrug-resistant serotype x variant in an epidemic clone of shigella flexneri.shigella spp. are the causative agent of shigellosis with shigella flexneri serotype 2a being the most prevalent in developing countries. epidemiological surveillance in china found that a new serotype of s. flexneri appeared in 2001 and replaced serotype 2a in 2003 as the most prevalent serotype in henan province. the new serotype also became the dominant serotype in 7 of the 10 other provinces under surveillance in china by 2007. the serotype was identified as a variant of serotype x. it diffe ...201019955273
a bacterial e3 ubiquitin ligase ipah9.8 targets nemo/ikkgamma to dampen the host nf-kappab-mediated inflammatory response.nf-kappab (nuclear factor kappab) has a pivotal role in many cellular processes, including the inflammatory and immune responses and, therefore, its activation is tightly regulated by the ikk (ikappab kinase) complex and by ikappabalpha degradation. when shigella bacteria multiply within epithelial cells they release peptidoglycans, which are recognized by nod1 and stimulate the nf-kappab pathway, thus leading to a severe inflammatory response. here, we show that ipah9.8, a shigella effector pos ...201020010814
osmoregulated periplasmic glucans synthesis gene family of shigella flexneri.osmoregulated periplasmic glucans (opgs) of food- and water-borne enteropathogen shigella flexneri were characterized. opgs were composed of 100% glucose with 2-linked glucose as the most abundant residue with terminal glucose, 2-linked and 2,6-linked glucose also present in high quantities. most dominant backbone polymer chain length was seven glucose residues. individual genes from the opg gene family comprising of a bicistronic operon opggh, opgb, opgc and opgd were mutagenized to study their ...201020062978
th17 cells are the dominant t cell subtype primed by shigella flexneri mediating protective immunity.the t cell response to shigella, the causative agent of bacillary dysentery, remains poorly understood. using a murine model of infection, we report that shigella flexneri primes predominately il-17a- and il-22-producing th17 cells. shigella-specific th1 cells are only significantly induced on secondary infection, whereas specific th2 and cd8(+) t cells are undetectable. apart from th17 cells that are primed in a mhc class ii- and il-6-dependent, but il12/23p40-independent manner, we identified ...201020089698
risk factors for sporadic shigellosis, foodnet 2005.an estimated 450,000 cases of shigellosis occur annually in the united states. outbreaks have been associated with food, water, child daycare centers, and men who have sex with men. however, for sporadic infections, which account for the majority of cases, risk exposures are poorly characterized.201020113209
the structure of the salmonella typhimurium type iii secretion system needle shows divergence from the flagellar system.the type iii secretion system (t3ss) is essential for the infectivity of many pathogenic gram-negative bacteria. the t3ss contains proteins that form a channel in the inner and outer bacterial membranes, as well as an extracellular needle that is used for transporting and injecting effector proteins into a host cell. the homology between the t3ss and the bacterial flagellar system has been firmly established, based upon both sequence similarities between respective proteins in the two systems an ...201020060835
nlrc4/ipaf/clan/card12: more than a flagellin sensor.nlrc4 is a member of the nod-like receptors (nlrs), a family of cytosolic receptors involved in sensing bacterial molecules. nlrs are a group of proteins containing spans of leucine-rich repeats that senses bacterial factors within the eukaryotic cytosol. the recognition of bacterial factors provokes the formation of the inflammasome complex which includes specific nlrs. the inflammasome is responsible for caspase-1 activation which leads to the cleavage and maturation of inflammatory cytokines ...201020067841
tracking the dynamic interplay between bacterial and host factors during pathogen-induced vacuole rupture in real time.escape into the host cell cytosol following invasion of mammalian cells is a common strategy used by invasive pathogens. this requires membrane rupture of the vesicular or vacuolar compartment formed around the bacteria after uptake into the host cell. the mechanism of pathogen-induced disassembly of the vacuolar membrane is poorly understood. we established a novel, robust and sensitive fluorescence microscopy method that tracks the precise time point of vacuole rupture upon uptake of gram-nega ...201020070313
characterisation of pathogenic bacteria in a uasb-polishing pond system using molecular techniques.molecular techniques have been commonly used to detect and quantify pathogenic bacteria in food, clinical and environmental samples, but in wastewater treatment plants few studies have been carried out. this work applied pcr with a specific set of primers to investigate pathogenic bacteria in a wastewater plant comprised of a uasb reactor followed by polishing ponds. in addition, in-situ hybridisation technique (fish) was used to estimate the abundance of escherichia coli in the system. accordin ...201020150719
a piglet model of acute gastroenteritis induced by shigella dysenteriae type 1.the lack of a standardized laboratory animal model that mimics key aspects of human shigellosis remains a major obstacle to addressing questions about pathogenesis, screening therapeutics, and evaluation of vaccines.201020136414
new enterovirulent escherichia coli serogroup 64474 showing antigenic and genotypic relationships to shigella boydii 16.studies based on the analysis of housekeeping genes indicate that escherichia coli and all shigella species, except for shigella boydii type 13, belong to a single species. this study analysed the phenotypic and genotypic characteristics of 23 e. coli strains isolated in different countries from faecal specimens taken from children with diarrhoea. strains were identified using the vitek system and typed with rabbit sera obtained against 186 somatic and 53 flagellar e. coli antigens and against 4 ...201020075111
the extreme c terminus of shigella flexneri ipab is required for regulation of type iii secretion, needle tip composition, and binding.type iii secretion systems (t3sss) are widely distributed virulence determinants of gram-negative bacteria. they translocate bacterial proteins into host cells to manipulate them during infection. the shigella t3ss consists of a cytoplasmic bulb, a transmembrane region, and a hollow needle protruding from the bacterial surface. the distal tip of mature, quiescent needles is composed of ipad, which is topped by ipab. physical contact with host cells initiates secretion and leads to assembly of a ...201020086081
influences of hydraulic loading rate on svoc removal and microbial community structure in drinking water treatment biofilters.six biofilters were used for advanced treatment of yangtze river source water to investigate the effects of hydraulic loading rate (hlr) on pollutant removal and microbial community. hlr was found to exert significant influences on the removal efficiency of the conventional pollutants and 24 detectable semivolatile organic compounds (svocs). more than 85% of chemical oxygen demand and assimilable organic carbon was removed at the optimal hlr of 3.0 m h(-1). with the increase of hlr, svoc removal ...201020189298
bacterial guanine nucleotide exchange factors sope-like and wxxxe effectors.subversion of rho family small gtpases, which control actin dynamics, is a common infection strategy used by bacterial pathogens. in particular, salmonella enterica serovar typhimurium, shigella flexneri, enteropathogenic escherichia coli (epec), and enterohemorrhagic escherichia coli (ehec) translocate type iii secretion system (t3ss) effector proteins to modulate the rho gtpases rhoa, cdc42, and rac1, which trigger formation of stress fibers, filopodia, and lamellipodia/ruffles, respectively. ...201020123714
mst (molecular serotyping tool): a program for computer-assisted molecular identification of escherichia coli and shigella o antigens.escherichia coli and shigella o antigens can be inferred using the rfb-restriction fragment length polymorphism (rflp) molecular test. we present herein a dynamic programming algorithm-based software to compare the rfb-rflp patterns of clinical isolates with those in a database containing the 171 previously published patterns corresponding to all known e. coli/shigella o antigens.201020200287
structural and functional divergence of the newly identified gtric from its gtr family of conserved shigella flexneri serotype-converting glucosyltransferases.glucosyltransferases (gtrs) and o-acetyltransferase (oac) are integral membrane proteins embedded within the cytoplasmic membrane of shigella flexneri. gtrs and oac are responsible for unidirectional host serotype conversion by altering the epitopic properties of the bacterial surface lipopolysaccharide (lps) o-antigen. in this study, we present the membrane topology of a recently recognized gtr, gtric, which is known to mediate s. flenxeri serotype switching from 1a to 1c. the gtric topology is ...201020095950
a novel antisense rna regulates at transcriptional level the virulence gene icsa of shigella flexneri.the virulence gene icsa of shigella flexneri encodes an invasion protein crucial for host colonization by pathogenic bacteria. within the intergenic region vira-icsa, we have discovered a new gene that encodes a non-translated antisense rna (named rnag), transcribed in cis on the complementary strand of icsa. in vitro transcription assays show that rnag promotes premature termination of transcription of icsa mrna. transcriptional inhibition is also observed in vivo by monitoring the expression p ...201020129941
cesarean delivery and risk of intestinal bacterial infection.an individual's intestinal bacterial flora is established soon after birth. delivery by cesarean section (c-section) deprives the newborn of colonization with maternal vaginal bacteria. we determined whether delivery by c-section is associated with an altered risk of infection with intestinal bacterial pathogens.201020132034
a yersinia pestis guaba mutant is attenuated in virulence and provides protection against plague in a mouse model of infection.there is a need to develop effective countermeasures for yersinia pestis, the etiologic agent of plague and a potential bioterrorism agent. salmonella and shigella spp. deleted in the guaba genes involved in guanine biosynthesis have been shown to be attenuated in vivo. in this study, we sought to determine whether deletion of the guaba operon would render y. pestis auxotrophic for guanine and avirulent; such a strain could serve as a live attenuated plague vaccine candidate. a y. pestis guaba m ...201020096773
[role of galactose-specific receptor--lectin in bactericidal activity of hemolysin of vibrio cholerae non o1/o139].to study the role lectin galactose-specific receptor of vibrio cholerae hemolysin in receptor mechanisms of bacterial cells lysis.201020218337
shigella mediated depletion of macrophages in a murine breast cancer model is associated with tumor regression.a tumor promoting role of macrophages has been described for a transgenic murine breast cancer model. in this model tumor-associated macrophages (tams) represent a major component of the leukocytic infiltrate and are associated with tumor progression. shigella flexneri is a bacterial pathogen known to specificly induce apotosis in macrophages. to evaluate whether shigella-induced removal of macrophages may be sufficient for achieving tumor regression we have developed an attenuated strain of s. ...201020221397
selective deletion of cd8(+) cells upregulated by caspases-1 via il-18 in mice immunized with major outer membrane protein of shigella dysenteriae 1 following infection.introduction: mucosal lymphoid changes were observed in cryopreserved rectal tissues obtained from balb/c mice infected with shigella dysenteriae 1, immunized with 57-kda major antigenic outer membrane protein, and infection after immunization. discussion: our data suggested that caspase-3 is downregulated in cd4(+) cells of immunized balb/c mice following infection with substantial increased expression of interleukin (il)-2 and interferon (ifn)-gamma, while caspase-1 is upregulated in cd8(+) ce ...201020084439
[shigella bacteremia dysentery in an adult]. 201020232025
nleh effectors interact with bax inhibitor-1 to block apoptosis during enteropathogenic escherichia coli infection.the human pathogens enteropathogenic (epec) and enterohemorrhagic escherichia coli and the related mouse pathogen citrobacter rodentium subvert a variety of host cell signaling pathways via their plethora of type iii secreted effectors, including triggering of an early apoptotic response. epec-infected cells do not develop late apoptotic symptoms, however. in this study we demonstrate that the nleh family effectors, homologs of the shigella effector kinase ospg, blocks apoptosis. during epec inf ...201020133763
bacteriocin production by shigella sonnei isolated from faeces of children with acute diarrhoea.shigella is a common agent of diarrhoea, a worldwide major health problem. the bacterium produces bacteriocins; however, the role of these substances as a virulence factor is completely unknown. with the aim to search for colicin production by shigella sonnei, to evaluate the influence of culture conditions on bacteriocin expression, and to characterize the substance partially, 16 s. sonnei strains isolated from children with diarrhoea were tested for antagonism against members of the intestinal ...201020132176
a repulsive electrostatic mechanism for protein export through the type iii secretion apparatus.many gram-negative bacteria initiate infections by injecting effector proteins into host cells through the type iii secretion apparatus, which is comprised of a basal body, a needle, and a tip. the needle channel is formed by the assembly of a single needle protein. to explore the export mechanisms of mxih needle protein through the needle of shigella flexneri, an essential step during needle assembly, we have performed steered molecular dynamics simulations in implicit solvent. the trajectories ...201020141759
innate immune detection of the type iii secretion apparatus through the nlrc4 inflammasome.the mammalian innate immune system uses toll-like receptors (tlrs) and nod-lrrs (nlrs) to detect microbial components during infection. often these molecules work in concert; for example, the tlrs can stimulate the production of the proforms of the cytokines il-1beta and il-18, whereas certain nlrs trigger their subsequent proteolytic processing via caspase 1. gram-negative bacteria use type iii secretion systems (t3ss) to deliver virulence factors to the cytosol of host cells, where they modula ...201020133635
shiga toxins: intracellular trafficking to the er leading to activation of host cell stress responses.despite efforts to improve hygenic conditions and regulate food and drinking water safety, the enteric pathogens, shiga toxin-producing escherichia coli (stec) and shigella dysenteriae serotype 1 remain major public health concerns due to widespread outbreaks and the severity of extra-intestinal diseases they cause, including acute renal failure and central nervous system complications. shiga toxins are the key virulence factors expressed by these pathogens mediating extra-intestinal disease. de ...201022069648
evaluation of antibacterial activity of 3-butenyl, 4-pentenyl, 2-phenylethyl, and benzyl isothiocyanate in brassica vegetables.this study investigated antibacterial activities of 4 isothiocyanates (3-butenyl, 4-phentenyl, 2-phenylethyl, and benzyl isothiocyanate) against 4 gram-positive bacteria (bacillus cereus, bacillus subtilis, listeria monocytogenes, and staphylococcus aureus) and 7 gram-negative bacteria (aeromonas hydrophila, pseudomonas aeruginosa, salmonella choleaesuis, salmonella enterica, serratia marcescens, shigella sonnei, and vibrio parahaemolyticus) by an agar disc diffusion assay. benzyl isothiocyanate ...201021535549
effect of nacl on the biofilm formation by foodborne pathogens.this study was designed to evaluate the effect of nacl on the biofilm formation of listeria monocytogenes, staphylococcus aureus, shigella boydii, and salmonella typhimurium. the biofilm cells were cultured in media containing different nacl concentrations (0% to 10%) for 10 d of incubation at 37 °c using a 24-well polystyrene microtiter plate, collected by swabbing methods, and enumerated using plate count method. the attachment and detachment kinetic patterns were estimated according to the mo ...201021535614
shiga toxin is transported into the nucleoli of intestinal epithelial cells via a carrier-dependent process.shiga toxin (stx) produced by the invasive shigella dysenteriae serotype 1 (s. dysenteriae1) causes gastrointestinal and kidney complications. it has been assumed that stx is released intracellularly after enterocyte invasion by s. dysenteriae1. however, there is little information about stx distribution inside s. dysenteriae1-infected enterocytes. here, we use intestinal epithelial t84 cells to characterize the trafficking of stx delivered into the cytosol, in ways that mimic aspects of s. dyse ...201022069640
enterobacteriaceae associated with eggs of podocnemis expansa and podocnemis unifilis (testudines:chelonia) in nonpolluted sites of national park of araguaia plains, brazil.fertile eggs of podocnemis expansa and podocnemis unifilis were investigated for the presence of enterobacteria, as these two endangered species have the potential for conservation measures that include egg transfer. knowledge of normal microflora associated with turtles and turtle eggs would help effectively manage the transfer of these eggs among institutions. thirty eggs of each species were collected, aseptically transferred, cracked inside plastic bags containing tetrathionate broth, and sp ...201021370647
ribonucleases and bacterial virulence.bacterial stress responses provide them the opportunity to survive hostile environments, proliferate and potentially cause diseases in humans and animals. the way in which pathogenic bacteria interact with host immune cells triggers a complicated series of events that include rapid genetic re-programming in response to the various host conditions encountered. viewed in this light, the bacterial host-cell induced stress response (hcisr) is similar to any other well-characterized environmental str ...201021375713
serine protease autotransporters of enterobacteriaceae (spates): biogenesis and function.serine protease autotransporters of enterobacteriaceae (spates) constitute a large family of proteases secreted by escherichia coli and shigella. spates exhibit two distinct proteolytic activities. first, a c-terminal catalytic site triggers an intra-molecular cleavage that releases the n-terminal portion of these proteins in the extracellular medium. second, the secreted n-terminal domains of spates are themselves proteases; each contains a canonical serine-protease catalytic site. some of thes ...201022069633
the shigella t3ss needle transmits a signal for mxic release, which controls secretion of effectors.type iii secretion systems (t3sss) are key determinants of virulence in many gram-negative bacteria, including animal and plant pathogens. they inject 'effector' proteins through a 'needle' protruding from the bacterial surface directly into eukaryotic cells after assembly of a 'translocator' pore in the host plasma membrane. secretion is a tightly regulated process, which is blocked until physical contact with a host cell takes place. host cell sensing occurs through a distal needle 'tip comple ...201021143311
etiology of childhood diarrhea in the northeast of brazil: significant emergent diarrheal pathogens.in a study conducted in joão pessoa, northeast of brazil, 2344 escherichia coli isolated from 290 infants with diarrhea and 290 healthy matched controls were analyzed for virulence traits. enteroaggregative e. coli (eaec) was the most prevalent pathogen associated to acute diarrhea. based on the results of colony blot hybridization, serotyping, and hep-2 cell adherence assays, strains were separated in categories as typical enteropathogenic e. coli (epec) (1.7%), atypical epec (a-epec) (9.3%), e ...201018508227
diarrhea in children less than two years of age with known hiv status in kisumu, kenya.to compare the frequency and etiology of diarrhea in children aged less than 2 years with known hiv status.201019664950
phenotypic and genotypic characterization of shigella spp. with reference to its virulence genes and antibiogram analysis from river narmada.water samples of the river narmada from origin to end were analyzed for the presence of shigellae. analysis of 40 water samples by biotyping, serotyping, and molecular typing were done. out of all 40 isolates, 23 were identified as shigella flexneri, 10 as shigella sonnei, and seven as shigella dysenteriae. serotyping was found to be a better identification method than biotyping since biotyping was not found to be very sharp. in the present investigation, amplified ribosomal dna restriction anal ...201019501495
evaluation of isolation methods for pathogenic yersinia enterocolitica from pig intestinal content.the aim of this study was to evaluate the efficiency of four isolation methods for the detection of pathogenic yersinia enterocolitica from pig intestinal content.201019735331
biennial hyperepidemic shigellosis in an observant jewish community.we aimed to study patterns of shigellosis in a large observant jewish community in israel and to describe local interventions during outbreaks. surveillance data from the ministry of health were used to calculate incidence rates in 1998-2006, both in the city of bene beraq and the tel aviv district. information on isolates was collected from the bacteriological laboratory of a community hospital. public notices and educational conferences conveyed a message to increase personal hygiene and keep ...201019602299
lactobacilli inhibit shigella dysenteriae 1 induced pro-inflammatory response and cytotoxicity in host cells via impediment of shigella-host interactions.shigella dysenteriae type 1 dysentery is a major cause of morbidity and mortality in children from less developed and developing countries. the present study explores the hypothesis that lactobacilli protect the host cell during s. dysenteriae type 1 infection and its mechanism of action.201019535308
a new multiplex pcr for differential identification of shigella flexneri and shigella sonnei and detection of shigella virulence determinants.most of the multiplex pcr (mpcr) used to identify shigella do not discriminate between shigella species or serotypes. we designed a mpcr to differentiate between s. flexneri and s. sonnei strains based on the detection of markers associated with the she pathogenicity island described in shigella. in addition, specific primers were included to detect the shigella virulence determinants shet-1 and shet-2 enterotoxin genes. the analysis of 304 shigella strains from chile and 79 shigella strains fro ...201019765332
survey of bacterial populations present in us-produced linerboard with high recycle content.to survey paperboard products from 17 us mills for bacterial populations and for bacteria potentially harmful to human health.201019645765
differential expression of enteric neuroimmune-network in invasive and acute watery diarrhoea.we aimed to evaluate the changes of nerve morphology and distribution of neurotransmitters and neuropeptides in the rectum of shigella flexneri-infected patients and in the duodenum of vibrio cholerae o1-infected patients. nerve morphology was observed by transmission electron microscopy. immunoreactivity of nerve growth factor (ngf), neurotransmitters and neuropeptides in tissues were studied by immunohistochemistry. ultrastructural analysis of intestinal biopsy revealed persisting axons degene ...201019650770
clinical practice. today's understanding of the haemolytic uraemic syndrome.the haemolytic uraemic syndrome (hus) includes the triad of haemolytic anaemia, thrombocytopenia, and acute renal failure. the classical form [d(+) hus] is caused by infectious agents, and it is a common cause of acute renal failure in children. the enterohaemorrhagic escherichia coli-producing shiga toxin (stx) is the most common infectious agent causing hus. other infectious agents are shigella and streptococcus pneumoniae. infections by s. pneumoniae can be particularly severe and has a highe ...201019707787
the escherichia coli o149 rfb gene cluster and its use for the detection of porcine e. coli o149 by real-time pcr.pcr or hybridization assays are widely used for the identification and detection of various escherichia coli serogroups and serotypes. this study explored this approach for the detection of e. coli o149 in pigs, a dominant serogroup among those associated with porcine post-weaning diarrhea (pwd) worldwide. for this purpose, we sequenced the o antigen (rfb) gene cluster of a representative enterotoxigenic e. coli (etec) o149:h10 strain and identified a 2kbp region specific for the o149 rfb gene c ...201019733452
magnitude of drug resistant shigellosis: a report from bangalore.shigella is an important cause of acute invasive diarrhea in children and others. antimicrobial susceptibility of shigella spp. isolated from diarrhoeal/ dysenteric patients in bangalore was studied in our hospital from january 2002 to december 2007. one hundred and thirty-four isolates were identified as shigella species. s. flexneri, s. sonnei , s. boydii and s. dysenteriae were accounted respectively for 64.9%, 21.6%, 8.2% and 3.7% of the total number of shigella isolated. of these 56 (41.8%) ...200919736408
transmission risk factors and treatment of pediatric shigellosis during a large daycare center-associated outbreak of multidrug resistant shigella sonnei: implications for the management of shigellosis outbreaks among children.shigellosis outbreaks in daycare centers result in substantial disease and economic burdens in the united states. the emergence of multidrug resistant shigella strains raises questions regarding control of transmission within daycare centers and treatment for children. from may to october 2005, 639 shigella sonnei cases were reported in northwest missouri, mostly among persons exposed to daycare centers.200919738503
high-affinity inhibitors of trna-guanine transglycosylase replacing the function of a structural water cluster.the trna-modifying enzyme trna-guanine transglycosylase (tgt) is essential for the pathogenic mechanism of shigella flexneri, the causing agent of the bacterial diarrheal disease shigellosis. herein, the synthesis of a new class of rationally designed 6-amino-imidazo[4,5-g]quinazolin-8(7h)-one- (lin-benzoguanine) based inhibitors of tgt are reported. in order to accommodate a small hydrophobic crevice opening near the binding site of ribose-34, 2-aminoethyl substituents were introduced in positi ...200919746363
analysis of a temporal cluster of shigella boydii isolates in mpumalanga, south africa, november to december 2007.shigellosis is a global human health problem. the disease is most prevalent in developing countries with poor access to safe potable water and sanitation. shigella boydii is of particular epidemiological importance in developing nations such as african and asian countries. in the present study, we report on the analysis of a temporal cluster of 29 s. boydii serotype 2 strains, isolated in the mpumalanga province of south africa (sa) over the period of november to december 2007.200919749451
bcl-2 regulates the onset of shiga toxin 1-induced apoptosis in thp-1 cells.shiga toxins (stxs), which are proteins expressed by the enteric pathogens shigella dysenteriae serotype 1 and some serotypes of escherichia coli, are potent protein synthesis inhibitors. stx-producing organisms cause bloody diarrhea with the potential to progress to acute renal failure and central nervous system complications. studies using animal models of these diseases have shown that stxs are major virulence factors, and purified toxins have been shown to be capable of killing many types of ...200919752028
effect of iron on cytolysin a expression in salmonella enterica serovar typhi.previously, a novel protein clya (cytolysin a) has been identified in escherichia coli k-12, salmonella enterica serovars typhi and paratyphi a and shigella. salmonella spp. synthesize substantial amounts of clya upon infection of the human host, although the mechanism by which clya is induced in vivo is unclear. since environmental signals could control the expression of virulence determinants, clya expression in s. typhi ty2 was tested by western blotting in the presence of normal pooled human ...200919763423
peptide sequences identified by phage display are immunodominant functional motifs of pet and pic serine proteases secreted by escherichia coli and shigella flexneri.plasmid-encoded toxin (pet) and protein involved in colonization (pic), are serine protease autotransporters of enterobacteriaceae (spates) secreted by enteroaggregative escherichia coli (eaec), which display the gdsgsg sequence or the serine motif. our research was directed to localize functional sites in both proteins using the phage display method. from a 12mer linear and a 7mer cysteine-constrained (c7c) libraries displayed on the m13 phage piii protein we selected different mimotopes using ...200919772881
antibiotic resistance among shigella serogroups isolated in tehran, iran (2002-2004). 200919801811
increasing resistance to nalidixic acid in shigella subgroups in a comparative study between 2001-2003 and 2004-2006.the shigella spp. is an organism with an ongoing changing resistance pattern to different antibiotics, thus making its appropriate treatment difficult. nalidixic acid has been one of the most common agents used for the treatment of shigellosis. recently, some studies have reported an emerging resistance to this agent.200919710978
multiplexed bead-based mesofluidic system for detection of food-borne pathogenic bacteria.in the present study, a simple and rapid multiplexed bead-based mesofluidic system (bms) was developed for simultaneous detection of food-borne pathogenic bacteria, including staphylococcus aureus, vibrio parahaemolyticus, listeria monocytogenes, salmonella, enterobacter sakazakii, shigella, escherichia coli o157:h7, and campylobacter jejuni. this system is based on utilization of isothiocyanate-modified microbeads that are 250 mum in diameter, which were immobilized with specific amino-modified ...200919717622
when shigella tells the cell to hang on.ospe, a shigella type iii effector binds to integrin-like kinase and enhances cell adhesion to better disseminate and colonize the intestinal epithelium. because of the existence of ospe orthologues in other enteropathogens such as enteropathogenic escherichia coli or salmonella sp., maintenance of cell adhesion appears as a widespread strategy for bacteria that interact with the intestinal epithelium.200919720630
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
assessment of cell surface properties and adhesion potential of selected probiotic strains.to evaluate the physicochemical cell surface and adhesive properties of selected probiotic strains for human use.200919725886
antibiotic therapy for shigella dysentery.shigella dysentery is a relatively common illness and occasionally causes death, worldwide. mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. the antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects.200919821387
prevalence of staphylococcus aureus and intestinal parasites among food handlers in sanliurfa, southeastern anatolia.food-borne diseases represent a persistent global health burden, and food handlers play a major role in their transmission. staphylococcus aureus carriage and intestinal parasitism are important risk factors for the contamination of food and water. this study was undertaken to determine the prevalence of staphylococcus aureus and intestinal parasites among food handlers working in sanliurfa, southeastern anatolia.200919823157
comparison of the entericbio multiplex pcr system with routine culture for detection of bacterial enteric pathogens.the entericbio system uses a multiplex pcr assay for the simultaneous detection of campylobacter spp., salmonella enterica, shigella spp., and escherichia coli o157 from feces. it combines overnight broth enrichment with pcr amplification and detection by hybridization. an evaluation of this system was conducted by comparing the results obtained with the system with those obtained by routine culture, supplemented with alternative pcr detection methods. in a study of 773 samples, routine culture ...200919726596
purification and characterization of an immunogenic outer membrane protein of shigella flexneri 2a.in the present study we purified 34 kda major outer membrane protein (momp) of shigella flexneri 2a for the first time, which was cross-reactive and antigenically conserved among shigella spp. and the epitope was surface exposed on the intact bacterium. the purified antigen was found to be glycosylated, which aids in binding to macrophages and up-regulated the production of nitric oxide, granulocyte-colony stimulating factor and il-12p70, indicating that the momp is immunogenic and has the abili ...200919660587
study on induction of apoptosis on hela and vero cells by recombinant shiga toxin and its subunits.verotoxin (vt) or shiga toxin (stx) produced by enterohemorrhagic escherichia coli (ehec) and shigella dysenteriae is ab5 holotoxin with potent protein synthesis inhibitor. vt can induce both apoptosis and necrosis depending on the cell type, it has been shown that vt-induced apoptosis and cytotoxicity are distinct processes, and the a subunit can be necessary for apoptosis. in other words, the precise role of each subunit in apoptosis signaling has yet to be established. in this study, inductio ...200919669659
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
bacterial jailbreak sounds cellular alarm: phagosome membrane remnants trigger signaling.shigella flexneri and other invasive bacteria rupture the phagosome membrane and escape to the host cytoplasm. now, dupont et al. address the fate and signaling functions of pathogen vacuole remnants and show that these membrane fragments trigger host-cell-signaling responses, including polyubiquitination, autophagy, and pyroptosis.200919683675
a genome-scale proteomic screen identifies a role for dnak in chaperoning of polar autotransporters in shigella.autotransporters are outer membrane proteins that are widely distributed among gram-negative bacteria. like other autotransporters, the shigella autotransporter icsa, which is required for actin assembly during infection, is secreted at the bacterial pole. in the bacterial cytoplasm, icsa localizes to poles and potential cell division sites independent of the cell division protein ftsz. to identify bacterial proteins involved in the targeting of icsa to the pole in the bacterial cytoplasm, we sc ...200919684128
protective role of mouse mbl-c on intestinal mucosa during shigella flexneri invasion.mannan-binding lectin (mbl) is a c-type serum lectin, which is believed to play an important role in the innate immunity against a variety of pathogens. mbl can bind to sugar determinants of a wide variety of microorganisms, neutralize them and inhibit infection by complement activation through the lectin pathway and opsonization by collectin receptors. given that small intestine is a predominant site of extrahepatic expression of mbl, here we addressed the question whether mbl is involved in mu ...200919684159
review article: anti-inflammatory mechanisms of action of saccharomyces boulardii.saccharomyces boulardii, a well-studied probiotic, can be effective in inflammatory gastrointestinal diseases with diverse pathophysiology, such as inflammatory bowel disease (ibd), and bacterially mediated or enterotoxin-mediated diarrhoea and inflammation.200919706150
microwave assisted, one-pot synthesis of 5-nitro- 2-aryl substituted-1h-benzimidazole libraries: screening in vitro for antimicrobial activity.the efficient and rapid synthesis of 5-nitro-2-aryl substituted-1h-benzimidazole libraries (1a-1j) has been established. thus, both microwave and conventional cyclo-condensation of 4-nitro ortho-phenylenediamine with various phenoxyacetic acids were carried out in the presence of hcl catalyst. the microwave synthesis route afforded advantages, such as good to excellent yields, shorter reaction time (2.5-3.5 min), readily available starting material, and simple purification procedure, which disti ...200919772484
vaccination of children in low-resource countries against shigella is unlikely to present an undue risk of reactive arthritis.shigellosis is a major cause of morbidity and mortality among children in low-resource countries. promising vaccine strategies in development include genetically attenuated shigella, killed whole cell vaccines, subcellular vaccines, and o-polysaccharide-protein conjugates. there is a concern that shigella vaccines could either induce reactive arthritis or could prime vaccinees for arthritis after a subsequent exposure to the pathogen because shigellosis is associated with reactive arthritis, esp ...200919643213
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
physicochemical, nutritional and antibacterial characteristics of the fruit of bromelia pinguin l.bromelia pinguin l. is a plant native to sinaloa, mexico, where its fruit is used as food or as a phytotherapeutic agent. the fruits of b. pinguin were characterized and they could be considered as a functional food. these fruits show an average weight of 13.7 g and a yellow color of high luminosity (b* = 43.2, l* = 74.5). the values for acidity (4.6%, as citric acid) and ph (3.7) of b. pinguin fruit are similar to those of citrics. the edible portion is characterized by a high content of vitami ...200919536651
antibiotic resistance among bacterial pathogens in central africa: a review of the published literature between 1955 and 2008.a systematic review of the published literature on bacterial resistance in central africa between 1955 and 2008 was performed. eighty-three publications from seven countries were retrieved, the majority presenting data on enteric and other gram-negative pathogens. despite methodological limitations in many studies, alarming resistance rates are noted in nearly all pathogens. of special concern are multidrug resistance in shigella and salmonella spp. and the emergence of meticillin-resistant stap ...200919540725
hospital-based surveillance of enteric parasites in kolkata.diarrhoea is the second leading cause of illness and death in developing countries and the second commonest cause of death due to infectious diseases among children under five in such countries. parasites, as well as bacterial and viral pathogens, are important causes of diarrhoea. however, parasitic infections are sometimes overlooked, leading after a period of time to an uncertain aetiology. in this paper we report the prevalence of giardia lamblia, entamoeba histolytica and cryptosporidium sp ...200919545355
screening, purification, and identification of the enzyme producing n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester from l-isoasparagine and l-phenylalanine methyl ester.screening was carried out for microorganisms able to produce n-(l-alpha-l-aspartyl)-l-phenylalanine methyl ester [apm] from l-isoasparagine and l-phenylalanine methyl ester hydrochloride. of the 422 strains examined, 44 strains belonging to the family enterobacteriaceae were found to produce apm. the enzyme catalyzing apm production was purified and identified as dipeptidase e.200919664550
nonculturable response of animal enteropathogens in the agricultural environment and implications for food safety.concerns about animal enteropathogen contamination of fresh horticultural products have,increased worldwide and are mainly due to the ability of bacteria to survive under stress conditions in the agricultural environment and during raw-vegetable processing. this review challenges the idea that the viable but nonculturable phenomenon that has been proven to occur in plant-associated environments contributes to human pathogen survival and might be correlated with foodborne infection. factors assoc ...200919610353
high frequency of hotspot mutations in core genes of escherichia coli due to short-term positive selection.core genes comprising the ubiquitous backbone of bacterial genomes are not subject to frequent horizontal transfer and generally are not thought to contribute to the adaptive evolution of bacterial pathogens. we determined, however, that at least one-third and possibly more than one-half of the core genes in escherichia coli genomes are targeted by repeated replacement substitutions in the same amino acid positions-hotspot mutations. occurrence of hotspot mutations is driven by positive selectio ...200919617543
[virulence factors and in vitro susceptibility of plesiomonas shigelloides isolated from diarrhea episodes in cuba].acute diarrhea is still one of the main causes of disease in developing countries. at the national reference laboratory for acute diarrhoeal diseases, of the "pedro kourí" tropical medicine institute, 54 plesiomonas shigelloides strains were serotyped. as a result, the circulation of four new serotypes (o20:h2, 056:h18, 071 :h31,081 :h22) was detected. the most common antigenic variant was 094:h3. in addition, the susceptibility pattern to 21 antimicrobial agents (aa) was studied. highest percen ...200919621156
enterohaemorrhagic escherichia coli serogroup o111 inhibits nf-(kappa)b-dependent innate responses in a manner independent of a type iii secreted ospg orthologue.enterohaemorrhagic and enteropathogenic escherichia coli (ehec and epec) inject a repertoire of effector proteins into host cells via a type iii secretion system (t3ss) encoded by the locus of enterocyte effacement (lee). ospg is an effector protein initially identified in shigella that was shown to inhibit the host innate immune response. in this study, we found ospg homologues in ehec (mainly of serogroup o111) and in yersinia enterocolitica. the t3ss encoded by the lee was able to inject thes ...200919628559
isolation of salmonella and shigella from fish harvested from the winam gulf of lake victoria, kenya.human infections caused by pathogens transmitted from fish are quite common. the aim of this study was to isolate enteric pathogenic bacteria from fish that might be transmitted to humans after the handling or consumption of such fish.200919755738
molecular characterization of esbl-producing shigella sonnei isolates from patients with bacilliary dysentery in lebanon.emergence of extended-spectrum beta-lactamases (esbls) in shigella species imparting resistance to third-generation cephalosporins is a growing concern worldwide. the aim of this study is to molecularly characterize the newly emerging beta-lactam resistant shigella sonnei, specifically esbls in lebanon, and compare them to beta-lactam sensitive isolates.200919759494
[development of single base extension-tags microarray for the detection of food-borne pathogens].we developed single base extension-tags (sbe-tags) microarray to detect eight common food-borne pathogens, including staphylococcus aureus, vibrio parahaemolyticus, listeria monocytogenes, salmonella, enterobacter sakazaki, shigella, escherichia coli o157:h7 and campylobacter jejuni. with specific pcr primers identified and integrated for eight food-borne pathogens, target sequences were amplified and purified as template dna of single base extension-tags reaction. the products were hybridized t ...200919637631
structural insights into host gtpase isoform selection by a family of bacterial gef mimics.the escherichia coli type iii effector map belongs to a large family of bacterial virulence factors that activate host rho gtpase signaling pathways through an unknown molecular mechanism. here we report direct evidence that map functions as a potent and selective guanine-nucleotide exchange factor (gef) for cdc42. the 2.3-a structure of the map-cdc42 complex revealed that map mimics the gef strategy of the mammalian dbl family but has a three-dimensional architecture that is nearly identical to ...200919620963
comparative study of pathogenicity tests for shigella spp. and enteroinvasive escherichia coli strains.the purpose of this study was to optimize an in vitro pathogenicity model, as an alternative to sereny test (on guinea pigs). the study was performed on 13 shigella spp. and 3 enteroinvasive escherichia coli (eiec) strains isolated in romania between 2005 and 2007. the investigation implied the comparative evaluation between the sereny test and cravioto's adapted method for the assessment of the adherence and invasion capacity of the studied bacterial strains on hela cells, as well as the pcr de ...200919507627
improvement of an acid phosphatase/dhap-dependent aldolase cascade reaction by using directed evolution.to enhance the phosphorylating activity of the bacterial nonspecific acid phosphatase from salmonella enterica ser. typhimurium lt2 towards dihydroxyacetone (dha), a mutant library was generated from the native enzyme. three different variants that showed enhanced activity were identified after one round of eppcr. the single mutant v78l was the most active and showed an increase in the maximal dhap concentration to 25 % higher than that of the wild-type enzyme at ph 6.0. this variant is 17 times ...200919623595
[isolation and study of perspective probiotic strain of spore-forming bacteria from bacillus genus].to study physiologic, biochemical as well as antagonistic characteristics of isolated strain of bacillus pumilus in comparison with known spore-forming bacteria from b. subtilis species.200919623717
[etiology of acute enteric infection in children with arid zone and effect of probiotics].to study etiologic structure of acute enteric infections (aei) with isolation of hemolytic and enteropathogenic escherichia and to assess the efficacy of probiotic therapy during infections caused by e. coli.200919623719
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