Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| spa32 regulates a switch in substrate specificity of the type iii secreton of shigella flexneri from needle components to ipa proteins. | type iii secretion systems (ttss) are essential virulence determinants of many gram-negative bacteria and serve, upon physical contact with target cells, to translocate bacterial proteins directly across eukaryotic cell membranes. the shigella ttss is encoded by the mxi/spa loci located on its virulence plasmid. by electron microscopy secretons are visualized as tripartite with an external needle, a transmembrane domain, and a cytoplasmic bulb. in the present study, we generated a shigella spa32 ... | 2002 | 12057936 |
| shigella deliver an effector protein to trigger host microtubule destabilization, which promotes rac1 activity and efficient bacterial internalization. | shigella deliver a subset of effectors into the host cell via the type iii secretion system, that stimulate host cell signal pathways to modulate the actin dynamics required for invasion of epithelial cells. here we show that one of the shigella effectors, called vira, can interact with tubulin to promote microtubule (mt) destabilization, and elicit protrusions of membrane ruffling. under in vitro conditions, vira inhibited polymerization of tubulin and stimulated mt destabilization. upon microi ... | 2002 | 12065406 |
| human monocytes kill shigella flexneri but then die by apoptosis associated with suppression of proinflammatory cytokine production. | shigella flexneri infection of human macrophages is followed by rapid bacterial escape into the cytosol and secretion of ipab, which activates caspase-1 to mediate cell death and release of mature interleukin (il)-1 beta. here we report a different outcome following infection of human peripheral blood monocytes. s. flexneri infects monocytes inefficiently in the absence of complement and, following complement-dependent uptake, cannot escape the endosomal compartment. consequently, bacteria are k ... | 2002 | 12065527 |
| shigella flexneri regulates tight junction-associated proteins in human intestinal epithelial cells. | shigella spp. are a group of gram-negative enteric bacilli that cause acute dysentery in humans. we demonstrate that shigella flexneri has evolved the ability to regulate functional components of tight junctions after interaction at the apical and basolateral pole of model intestinal epithelia. in the regulation of tight junctional protein assemblies, s. flexneri can engage serotype-specific mechanisms, which targets not only expression, but also cellular distribution and membrane association of ... | 2002 | 12067320 |
| shiga toxin genes in avian escherichia coli. | the purpose of this study was to determine the presence of stx genes in avian pathogenic escherichia coli (apec). we examined 97 apec isolates: 34 from lesions of avian cellulitis, 31 from avian septicemia, 13 from swollen head syndrome (shs) in chickens, and 19 from diseased turkeys. we also examined five isolates from the feces of healthy chickens. all 102 e. coli isolates were tested for the presence of stx genes by pcr amplification and by colony blots using probes specific for stx1 and stx2 ... | 2002 | 12069771 |
| purification of lactoperoxidase from creek-water buffalo milk and investigation of kinetic and antibacterial properties. | water buffalo lactoperoxidase (wblp) was purified with amberlite cg 50 h+ resin, cm sephadex c-50 ion-exchange chromatography, and sephadex g-100 gel filtration chromatography from skim milk. all purification steps of the wblp were shown with sds-page and rz (a412/a280) controlled the purification degree of the enzyme. rz value for the purified wblp was 0.8. to determine purification steps and kinetic properties, the activity of enzyme was measured by using 2,2-azino-bis-(3-ethylbenzthiazoline-6 ... | 2002 | 12071645 |
| [the current status of infectious enteritis in japan--reports of the "research group for infectious enteric diseases, japan" in the last 5 years (1996-2000)]. | the patients or carriers with infectious enteritis admitted to the hospitals for infectious diseases in the last 5 years (1996-2000) were studied. the total number of cases admitted in each year were 969, 1,113, 981, 637 and 573 respectively. a total of 1,527 shigella spp. strains including 1,078 strains from overseas travelers' cases were isolated. the isolates of salmonella spp. excluding s. typhi and s. paratyphi a were 562 in number. a total of 61 vibrio cholerae o1 strains including 44 stra ... | 2002 | 12073571 |
| [development of vaccine for enterohemorrhagic escherichia coli infection]. | efforts on the development of vaccines against enterohemorrhagic escherichia coli (ehec) infection has been described in this review. two kinds of vaccines were developed and these have been targeted for in humans and cattle. one vaccine candidate is toxoid, which uses an inactive form of shiga toxin(stx). a part of b subunit, each b or a subunit or one or two amino acid mutated holotoxin were developed as a toxoid vaccine candidate. the other candidate was bacterial surface antigen such as a li ... | 2002 | 12078077 |
| [effect of cytokines on the expression of shiga toxin toxicity]. | shiga toxins(stxs), which are produced by enterohemorrhagic escherichia coli and shigella dysenteriae serotype i, induce proinflammatory cytokines including tumor necrosis factor-alpha, interleukin(il)-1 beta, il-6, interferon-gamma, and chemokines such as il-8 in intestinal epithelial cells, vascular endothelial cells, and monocytes/macrophages in vitro and in kidneys and spleen in vivo. cytokines induced by stxs and lipopolysaccharide enhance the toxicity of stxs via up-regulation of the expre ... | 2002 | 12078078 |
| enterotoxigenic escherichia coli as cause of diarrhea among mexican adults and us travelers in mexico. | enterotoxigenic escherichia coli (etec) is the most common pathogen identified in travelers to mexico with diarrhea. there have been few recent studies looking at the etiology of diarrhea in travelers compared with the local resident population. | 2002 | 12088579 |
| phenotypic and genotypic characterization of serologically atypical strains of shigella flexneri type 4 isolated in dhaka, bangladesh. | twenty-one atypical shigella flexneri type 4 strains isolated from patients attending the dhaka treatment center of the international centre for diarrhoeal disease research, bangladesh, were extensively characterized and compared with s. flexneri serotypes 4a and 4b. the atypical strains agglutinated only with the type antigen factor 4 and did not agglutinate with any group factors, thereby excluding their characterization into serotype 4a or 4b. of the 21 strains, 85.7% did not ferment mannitol ... | 2002 | 12089268 |
| [diversity within a population of shigella sonnei according to markers of medicinal preparations]. | as revealed in this study, s. sonnei population is represented by two clusters with respect to the sensitivity to different antibiotics. a higher degree of diversity was observed with respect to the action of streptomycin, kefzol, ampicillin, chloramphenicol and kanamycin in comparison with the action of gentamicin, nevigramon, rafampicin, tetracycline and polymyxin. the level of diversity of s. sonnei with respect to the sensitivity to antibiotics under study underwent essential changes during ... | 2002 | 12043156 |
| [clinical and morphological aspects of shigellosis flexneri in patients with an aggravated premorbid state]. | the analysis of 10 fatal outcomes in patients with acute shigellosis during the period of 1999-2000 made it possible to find out that most of deceased shigellosis patients belonged to the group inclined to alcohol abuse and having initial alimentary disturbances. in 6 cases of acute shigellosis with fatal outcome the causative agent was s. flexneri 2a, in 2 cases--s. flexneri 3a, in 1--s. flexneri 4b. the main cause of fatal outcomes was accompanying double pneumonia. lesions of the intestinal t ... | 2002 | 12043161 |
| [molecular characterization of resistance mechanisms to chloramphenicol in shigella flexneri strains isolated from chilean children with acute diarrhea]. | chloramphenicol is one of the therapeutic options for shigellosis, but resistance to this antimicrobial is increasing. | 2002 | 12043369 |
| representational difference analysis uncovers a novel is10-like insertion element unique to pathogenic strains of yersinia enterocolitica. | the method of suppressive subtractive hybridization was employed to map out genomic differences between the highly pathogenic yersinia enterocolitica (ye) biogroup 1b, serotype o:8 strain (wa-314) and the closely related apathogenic y. enterocolitica biogroup 1a, serotype o:5 strain (nf-o). a novel is10-like element, is1330, uncovered by this technique was found to be uniquely present in high copy numbers among the highly pathogenic y. enterocolitica 1b strains, while a single copy of the elemen ... | 2002 | 12044683 |
| [studies on the actin-based spreading of shigella]. | 2002 | 12048885 | |
| development of an elisa using a recombinant 41 kda partial protein (p45n') for the detection of riemerella anatipestifer infections in ducks. | riemerella anatipestifer, a gram-negative bacillus, is the causative agent of duck septicemia, a disease which could incur much economic loss in the duck industry. an indirect enzyme-linked immunosorbent assay (elisa) has been developed to facilitate early detection of r. anatipestifer infection in ducks. the antigen used was a recombinant 41 kda n-terminal fragment (rp45n') of a newly characterized r. anatipestifer potential surface protein, p45, which was expressed in escherichia coli as an n- ... | 2002 | 12220809 |
| [ct evaluation of infectious colitis]. | computed tomography (ct) is useful for evaluating the diagnosis of gastrointestinal disease, such as infectious colitis, in patients with severe pain and bloody diarrhea. during the 7 years between november 1993 and october 2000, 34 patients with infectious colitis (18 male, 16 female; mean age 42 +/- 19 yrs), received emergency ct and colonoscopy because of severe abdominal pain and dysentery. the following organisms were isolated: pathogenic escherichia coli (12), 6 of which were o157:h7 (o-15 ... | 2002 | 12229165 |
| effect of organic acids and temperature on survival of shigella flexneri in broth at ph 4. | the survival of bacterial pathogens in acidified foods depends not only on the hydrogen ion concentration, but also on the type of acid and the storage temperature. shigella flexneri is a foodborne pathogen that is acid tolerant. the survival of s. flexneri 5348 in brain heart infusion broth supplemented with 0.04 m acetic, citric, lactic, malic, or tartaric acid and adjusted to ph 4 with hci or naoh was studied. the control medium was brain heart infusion broth adjusted to ph 4 with hci. statio ... | 2002 | 12233851 |
| development of an enzyme assay for rapid assessment of escherichia coli in seawaters. | an analytical protocol has been developed and applied for the detection of glucuronidase activity in marine waters as a rapid alternative approach to assess the microbiological quality of seawaters. | 2002 | 12234337 |
| infectious diseases in mexico. a survey from 1995-2000. | data obtained at a central laboratory for emerging, re-emerging, and other infectious diseases in mexico from 1995-2000 are presented. an outstanding increase of den-3 circulation was identified. aedes aegypti, the dengue vector, is widely distributed. leptospirosis has become the most important differential diagnosis for dengue. identification of rabies virus variants allowed cataloging of new transmitters of rabies. rotavirus showed a clear seasonal distribution, while different proportions of ... | 2002 | 12234523 |
| survival and growth of shigella flexneri, salmonella enterica serovar enteritidis, and vibrio cholerae o1 in reconstituted infant formula. | formula feeding is an alternative method to prevent mother-to-child infection with human immunodeficiency virus through breast-feeding in developing countries. growth of bacterial pathogens in reconstituted infant formula has become a health hazard when contaminated water is used for rehydration. this study was conducted to assess bacterial safety risk of using contaminated water to reconstitute infant formula. survival and growth characteristics were determined for three bacterial pathogens, vi ... | 2002 | 12224592 |
| evaluation of an immunochromatography strip assay for the detection of salmonella sp. from poultry. | the present study was conducted to evaluate the sensitivity and specificity of an immunochromatography-based diagnostic kit for salmonella. the analytical sensitivity of the test when using pure colonies of different salmonella species was in the range of 1 x 10(4) to 1 x 10(5) colony-forming units per milliliter. the strip detected 19 of 22 strains of salmonella spp. but failed to detect s. worthington, s. choleraesuis var. kunzendorf and s. johannesburg. the strip did not detect 27 different e ... | 2002 | 12296399 |
| neural wiskott-aldrich syndrome protein (n-wasp) is the specific ligand for shigella virg among the wasp family and determines the host cell type allowing actin-based spreading. | shigella, the causative agent of bacillary dysentery, is capable of directing its movement within host cells by forming an actin comet tail. the virg (icsa) pro-tein expressed at one pole of the bacterium recruits neural wiskott-aldrich syndrome protein (n-wasp), a member of the wasp family, which in turn stimulates actin-related protein (arp) 2/3 complex-mediated actin polymerization. as all the wasp family proteins induce actin polymerization by recruiting arp2/3 complex, we investigated their ... | 2002 | 11952639 |
| feasibility of introducing rejection criteria for stool cultures in a teaching hospital in portugal. | the possible introduction of rejection criteria for stool cultures (<or= 3 days hospitalization and <or= 2 specimens) were investigated in a teaching hospital in portugal. during 12 months, 854 specimens from 537 patients (37% of them adults) were observed. sixteen percent of inpatients had a positive stool culture (adults 9.7%, pediatric 21.7%). eighty-five percent had <or= 3 days of hospitalization. application of the '3-day-rule' would have led to 12 missed cases. only in three cases would pr ... | 2002 | 11952727 |
| spa15 of shigella flexneri, a third type of chaperone in the type iii secretion pathway. | the type iii secretion (tts) pathway is used by numerous gram-negative pathogens to inject virulence factors into eukaryotic cells. in addition to a functional tts apparatus, secretion of effector proteins depends upon specific chaperones. using a two-hybrid screen in yeast and a co-purification assay in shigella flexneri, we demonstrated that spa15, which is encoded by an operon for components of the tts apparatus, is associated in the cytoplasm with three proteins that are secreted by the tts ... | 2002 | 11952903 |
| [phenomenon of apoptosis in the survival of enterobacteria in the parasite-host system]. | data on the apoptosis phenomenon with enterobacteria used as a model are presented. one of the mechanisms regulating the vital activity of eukaryotic cells is, together with cell proliferation and differentiation, the phenomenon known as "apoptosis". this physiological process of the eukaryotic cells death is used by many parasites in parasite--host relationships in different epitopes. the system known to trigger programmed cell death, is the surface receptor fas, the receptor of tumor necrosis ... | 2002 | 11949266 |
| host-pathogen interactions: the seduction of molecular cross talk. | bacterial pathogens have evolved two major strategies to colonise the intestinal epithelium. adherent microorganisms bind to the apical pole of the intestinal epithelium, whereas invasive microorganisms disrupt and invade the epithelium. recognition of the genetic bases of bacterial pathogenicity and analysis of the molecular cross talks established between pathogens and their mammalian target cells have illuminated this diversity of interactions. we have compared the strategies of enteroinvasiv ... | 2002 | 11953325 |
| delayed and reduced adaptive humoral immune responses in children with shigellosis compared with in adults. | we hypothesized that increased susceptibility to shigella infection, increased severity of disease and high mortality in children compared with adults were consequences of insufficient adaptive immune responses. antigen-specific immune responses were studied in paediatric patients (n = 38, 2-10 years) with shigellosis and compared with those of adult patients (n = 30, 18-45 years). peak frequencies of antigen (invasion plasmid coded antigen b, ipa-b; lipopolysaccharide, lps)-specific immunoglobu ... | 2002 | 11967124 |
| regulation of transcription by the activity of the shigella flexneri type iii secretion apparatus. | the virulence plasmid-encoded type iii secretion system of shigella flexneri consists of the mxi-spa secretion apparatus, secreted proteins ipaa-d and ipgd involved in entry of bacteria into epithelial cells,cytoplasmic chaperones ipgc and ipge and 15 other secreted proteins of unknown function, including vira and members of the ipah family. the activity of the mxi-spa apparatus is regulated by external signals, and transcription of vira and ipah genes is specifically induced in conditions of ac ... | 2002 | 11971264 |
| abdominal infections in patients with acute leukaemia: a prospective study applying ultrasonography and microbiology. | a prospective study of 62 chemotherapy-induced neutropenic episodes in patients with acute leukaemia was conducted to determine the incidence and causes of abdominal infections, and to assess the diagnostic value of the combined use of ultrasonography (us) and microbiology. each patient underwent us of liver, gallbladder and complete bowel before chemotherapy, on days 2-4 after the end of chemotherapy and in cases of fever, diarrhoea or abdominal pain. us was combined with a standardized clinica ... | 2002 | 11972517 |
| genomic subtraction to identify and characterize sequences of shiga toxin-producing escherichia coli o91:h21. | to identify shiga toxin-producing escherichia coli genes associated with severe human disease, a genomic subtraction technique was used with hemolytic-uremic syndrome-associated o91:h21 strain ch014 and o6:h10 bovine strains. the method was adapted to the shiga toxin-producing e. coli genome: three rounds of subtraction were used to isolate dna fragments specific to strain ch014. the fragments were characterized by genetic support analysis, sequencing, and hybridization to the genome of a collec ... | 2002 | 11976103 |
| rapid detection of shigella species in environmental sewage by an immunocapture pcr with universal primers. | in the present study, we developed a quick, highly specific method for detection of shigella species by combining immunocapturing of the bacteria and a universal primer pcr. the method drastically enhances test sensitivity, and it can be used not only for identification of shigella species in the environment but also for rapid detection of other pathogens. | 2002 | 11976139 |
| characterization of pecl18 and pkpn2: a proposed pathway for the evolution of two plasmids that carry identical genes for a type ii restriction-modification system. | the primary structures of the plasmids pecl18 (5571 bp) and pkpn2 (4196 bp) from escherichia coli and klebsiella pneumoniae, respectively, which carry genes for a type ii restriction-modification system (rms2) with the specificity 5'-ccngg-3', were determined in order to elucidate the structural relationship between them. the data suggest a possible role for recombination events at bom (basis of mobility) regions and the sites of resolution of multimer plasmid forms (so-called cer sequences) in ... | 2002 | 11976960 |
| quantification of shigella icsa required for bacterial actin polymerization. | shigella move through the cytoplasm of host cells by active polymerization of host actin to form an "actin tail." actin tail assembly is mediated by the shigella protein icsa. the process of shigella actin assembly has been studied extensively using icsa-expressing escherichia coli in cytoplasmic extracts of xenopus eggs. however, for reasons that have been unclear, wild type shigella does not assemble actin in these extracts. we show that the defect in actin assembly in xenopus extracts by shig ... | 2002 | 11977093 |
| cytotoxicity and interleukin-1beta processing following shigella flexneri infection of human monocyte-derived dendritic cells. | shigella flexneri infection of macrophages (mphi) leads to activation of caspase-1 by the ipab virulence factor, which induces rapid cell death and release of mature il-1beta. here we show that s. flexneri infection of human monocyte-derived dendritic cells (dc) also results in rapid ipab-dependent death. cytotoxicity is only partially blocked by the caspase-1 inhibitor yvad, but completely blocked by the pan-caspase inhibitor z-vad. cytotoxicity is also partially blocked by glycine without affe ... | 2002 | 11981835 |
| development of an oral prime-boost strategy to elicit broadly neutralizing antibodies against hiv-1. | given the increasing incidence of hiv-1 infection world-wide, an affordable, effective vaccine is probably the only way that this virus will be contained. accordingly, our group is developing an oral prime-boost strategy with the primary goal of eliciting broadly neutralizing antibodies against hiv-1 to provide sterilizing immunity for this virus. our secondary goal is to elicit broadly cross-reactive anti-viral cd8(+) t cells by this strategy to blunt any breakthrough infections that occur afte ... | 2002 | 11983256 |
| bromoperoxidase activity of vanadate-substituted acid phosphatases from shigella flexneri and salmonella enterica ser. typhimurium. | vanadium haloperoxidases and the bacterial class a nonspecific acid phosphatases have a conserved active site. it is shown that vanadate-substituted recombinant acid phosphatase from shigella flexneri (phon-sf) and salmonella enterica ser. typhimurium (phon-se) in the presence of h2o2 are able to oxidize bromide to hypobromous acid. vanadate is essential for this activity. the kinetic parameters for the artificial bromoperoxidases have been determined. the km value for h2o2 is about the same as ... | 2002 | 11985594 |
| two msbb genes encoding maximal acylation of lipid a are required for invasive shigella flexneri to mediate inflammatory rupture and destruction of the intestinal epithelium. | shigella flexneri is a gram-negative pathogen that invades and causes inflammatory destruction of the human colonic epithelium, thus leading to bloody diarrhea and dysentery. a type iii secretion system that delivers effector proteins into target eukaryotic cells is largely responsible for cell and tissue invasion. however, the respective role of this invasive phenotype and of lipid a, the endotoxin of the shigella lps, in eliciting the inflammatory cascade that leads to rupture and destruction ... | 2002 | 11994481 |
| commonly conserved genetic fragments revealed by genome profiling can serve as tracers of evolution. | we developed a method to produce, identify and analyze dna fragments for the purpose of taxonomic classification. genome profiling (gp) is a strategy that identifies genomic dna fragments common to closely related species without prior knowledge of the dna sequence. random pcr, one of the key technologies of gp, is used to produce fragments and may be used even when there are mutations at the priming site. these fragments can then be distinguished based on the information of mobility and melting ... | 2002 | 12000847 |
| incidence and molecular analysis of vibrio cholerae associated with cholera outbreak subsequent to the super cyclone in orissa, india. | an epidemiological study was carried out to find out the aetiological agent for diarrhoeal disorders in the cyclone and flood affected areas of orissa, india. rectal swabs collected from 107 hospitalized diarrhoea patients were bacteriologically analysed to isolate and identify the various enteropathogens. detection of toxic genes among e. coli and v. cholerae was carried out by polymerase chain reaction (pcr) assay. of the 107 rectal swabs analysed, 72.3% were positive for v. cholerae o1 ogawa, ... | 2002 | 12002529 |
| rhamnose-binding lectins from steelhead trout (oncorhynchus mykiss) eggs recognize bacterial lipopolysaccharides and lipoteichoic acid. | the interaction between bacteria and three l-rham-nose-binding lectins, named stl1, stl2, and stl3, from steelhead trout (oncorhynchus mykiss) eggs was investigated. although stls bound to most gram-negative and gram-positive bacteria, they agglutinated only escherichia coli k-12 and bacillus subtilis among the bacteria tested. the binding was inhibited by l-rhamnose. stls bound to distinct serotypes of lipopolysaccharides (lpss), and showed much higher binding activities to smooth-type lpss of ... | 2002 | 12005056 |
| enhancement of pentylenetetrazole-induced seizures by shigella dysenteriae in lps-resistant c3h/hej mice: role of the host response. | convulsions and encephalopathy are common complications of shiga toxin (stx)-producing shigella and enterohemorrhagic escherichia coli infections. in previous studies, we demonstrated that stx and lipopolysaccharide (lps) act in concert to enhance mice sensitivity to pentylenetetrazole (ptz)-induced seizures via mechanisms involving tumor necrosis factor alpha (tnfalpha), interleukinl beta and nitric oxide. to further elucidate the role of the host response in shigella-related seizures, we studi ... | 2002 | 12005330 |
| [salmonella spp. serotypes isolated at the hospital universitario reina sofía in córdoba during an 8-year period, 1993-2000]. | as a producer of gastro-enteritis and other symptoms, salmonella spp. remains an important problem for world public health. epidemiological knowledge at both general and local level by means of serotypification is considered one of the fundamental aspects for its control. | 2002 | 12006258 |
| delivery of dangerous goods: type iii secretion in enteric pathogens. | type iii secretion systems (ttsss) of gram-negative pathogens are molecular syringes that inject bacterial virulence factors directly into host cells. these virulence factors manipulate host cell pathways to aid bacterial survival within the host. four important enteric pathogens use ttsss to colonize and persist within the intestinal environment. the following is a brief review of the way in which ttsss and their effectors contribute to the pathogenic nature of the prototypic diarrheal pathogen ... | 2002 | 12008913 |
| regulation of the overlapping pic/set locus in shigella flexneri and enteroaggregative escherichia coli. | most strains of shigella flexneri 2a and enteroaggregative escherichia coli carry a highly conserved chromosomal locus which encodes a 109-kda secreted mucinase (called pic) and, on the opposite strand in overlapping fashion, an oligomeric enterotoxin called shet1, encoded by the seta and setb genes. here, we characterize the genetic regulation of these overlapping genes. our data suggest that pic and the setba loci are transcribed as complementary 4-kb mrna species. the major pic promoter is ma ... | 2002 | 12010980 |
| construction, characterization, and animal testing of wrsd1, a shigella dysenteriae 1 vaccine. | wrsd1 is a shigella dysenteriae 1 vaccine containing deletions of the virg(icsa) gene required for intercellular spreading and a 20-kb chromosomal region encompassing the shiga toxin genes (stxab). wrsd1 was constructed from s. dysenteriae 1 strain 1617 that was originally isolated during the 1968 to 1969 epidemic of shiga dysentery in guatemala. the virg(icsa) deletion was constructed from a streptomycin-resistant (str(r)) mutant of 1617 by a filter mating procedures using a virg(icsa) deletion ... | 2002 | 12010984 |
| apoptosis in acute shigellosis is associated with increased production of fas/fas ligand, perforin, caspase-1, and caspase-3 but reduced production of bcl-2 and interleukin-2. | shigella dysenteriae type 1-induced apoptotic cell death in rectal tissues from patients infected with shigella dysenteriae type 1 was studied by the terminal deoxynucleotidyltransferase-mediated dutp-biotin nick end labeling (tunel) technique and annexin v staining. expression of proteins and cytokines participating in the apoptotic process (caspase-1, caspase-3, fas [cd95], fas ligand [fas-l], perforin, granzyme a, bax, waf-1, bcl-2, interleukin-2 [il-2], il-18, and granulocyte-macrophage colo ... | 2002 | 12011015 |
| pathogenicity islands of shigella. | 2002 | 12014181 | |
| the dynamics of actin-based motility depend on surface parameters. | in cells, actin polymerization at the plasma membrane is induced by the recruitment of proteins such as the arp2/3 complex, and the zyxin/vasp complex. the physical mechanism of force generation by actin polymerization has been described theoretically using various approaches, but lacks support from experimental data. by the use of reconstituted motility medium, we find that the wiskott aldrich syndrome protein (wasp) subdomain, known as vca, is sufficient to induce actin polymerization and move ... | 2002 | 12015607 |
| neutrophil elastase targets virulence factors of enterobacteria. | shigellae cause bacillary dysentery, a bloody form of diarrhoea that affects almost 200 million people and causes nearly 2 million deaths per year. shigella invades the colonic mucosa, where it initiates an acute inflammation, rich in neutrophils, that initially contributes to tissue damage and eventually resolves the infection. neutrophils are phagocytic cells that kill microorganisms but it is unclear how neutrophils control pathogenic bacteria expressing virulence factors that manipulate host ... | 2002 | 12018205 |
| distinct recent lineages of the stra- strb streptomycin-resistance genes in clinical and environmental bacteria. | we report the linkage of the stra-strb streptomycin-resistance genes with class 1 integron sequences on pstr1, a 75-kb multiple antibiotic-resistance plasmid from shigella flexneri. stra-strb had previously been detected only within tn 5393, a tn 3-family transposon, and on small nonconjugative broad-host-range plasmids such as rsf1010. the geographic range of tn 5393 was also extended to pseudomonas spp. isolated from apple trees in new zealand and soil in the usa. comparative sequence analyses ... | 2002 | 12029529 |
| [shigella boydii strains possessing a new serovar (sm00-27) isolated from diarrhea of overseas travelers in japan]. | five shigella strains isolated from stool cultures of five sporadic imported diarrheal cases in japan during 1999-2001, did not react to any antisera of the established shigella serovars. these strains had the typical biochemical characteristics of shigella boydii, and were biochemically identical. all strains were positive in a pcr assay and a cultured-cell invasion test for invasiveness; these indicate that they can cause shigellosis in humans. the results of antigenic analysis revealed that t ... | 2002 | 12030026 |
| the effect of nacl on survival of shigella flexneri in broth as affected by temperature and ph. | shigella, a major foodborne pathogen, survives well in salt-containing environments. however, systematic data are scarce. we studied the behavior of shigella flexneri 5348 in brain heart infusion broth (ph 4 to 6) containing 0.5 to 8% nacl. stationary-phase cells were inoculated into sterile media at initial concentrations of 6 to 7 log10 cfu/ml and incubated at 12 to 37 degrees c. bacterial population sizes were determined periodically by plate counts. survivor curves were derived from plate co ... | 2002 | 12030287 |
| inorganic polyphosphate is essential for long-term survival and virulence factors in shigella and salmonella spp. | the importance of inorganic polyphosphate (poly p) and poly p kinase (ppk), the enzyme principally responsible for its synthesis, has been established previously for stationary-phase survival of escherichia coli and virulence in pseudomonas aeruginosa. the gene (ppk) that encodes ppk is highly conserved among many bacterial pathogens, including shigella and salmonella spp. in view of the phylogenetic similarity of the enteropathogens and the frequency with which virulence factors are expressed i ... | 2002 | 12032342 |
| mucosal dna vaccination with highly attenuated shigella is superior to attenuated salmonella and comparable to intramuscular dna vaccination for t cells against hiv. | an immunization strategy using attenuated bacteria to deliver dna vaccine plasmids to mucosal sites may induce protective t cell responses against sexual hiv transmission. in a murine intranasal (i.n.) immunization model, we demonstrate that transiently persistent deltaasd shigella flexneri strain 15d harboring dna vaccines induces hiv- and siv-specific gamma interferon (ifn-gamma) producing cd8+ t cells among splenocytes more efficiently than either a longer persisting deltaarod salmonella typh ... | 2002 | 12036602 |
| development of oligonucleotide primers for the specific pcr-based detection of the most frequent enterobacteriaceae species dna using wec gene templates. | oligonucleotide primers were designed for the pcr-based detection of the wec gene cluster involved in the biosynthetic pathway leading to the production of enterobacterial common antigen (eca). escherichia coli dna was detected using wec a, wec e, and wec f gene primers. the wec a primers were specific for e. coli. the wec e and wec f primers enabled the detection of the most frequent species of the enterobacteriaceae found in blood and urine specimens as well as in water. the sensitivity of the ... | 2002 | 11958564 |
| pcr detection of specific pathogens in water: a risk-based analysis. | the relative concentration of pathogens in water samples collected from storm drains and adjacent surfaces was evaluated using established pcr-based protocols. out of the 58 samples collected from 21 different storm drains, 22% were pcr positive for escherichia coli etec, salmonella, or adenovirus. the risk of swimming related illnesses associated with detection of e. coli etec and salmonella ranged from 0.39 to 30:100 000 and 0.3-25:1000, respectively. the detection limit corresponding to a neg ... | 2002 | 12099475 |
| bacterial enteropathogens and factors associated with seasonal episodes of gastroenteritis in nsukka, nigeria. | each year, between april and october, many children of school age and some young adults in nsukka, nigeria suffer from gastroenteritis. the period covers the rainy season in this part of africa, when manured farmland occasionally is flooded. in view of the number of people suffering diarrhoea and occasionally low-grade fever, it became necessary to investigate the nature of the bacterial agents responsible. between april and october (1996-1998), 500 loose or watery stools were collected from pat ... | 2002 | 12113407 |
| prevalence of the genes for shigella enterotoxins 1 and 2 among clinical isolates of shigella in israel. | two enterotoxins, shigella enterotoxin 1 (shet1) and shigella enterotoxin 2 (shet2) have been recently characterized and are believed to play a role in the clinical manifestation of shigellosis. one hundred and twenty-one isolates of shigella spp. of 13 different serotypes and variants and 10 isolates of enteroinvasive escherichia coli (eiec) isolated in israel, were examined by polymerase chain reaction for the presence of shet1 and shet2 genes. shet1 was only prevalent among isolates of s. fle ... | 2002 | 12113500 |
| identification of chromosomal shigella flexneri genes induced by the eukaryotic intracellular environment. | upon entry into the eukaryotic cytosol, the facultative intracellular bacterium shigella flexneri is exposed to an environment that may necessitate the expression of particular genes for it to survive and grow intracellularly. to identify genes that are induced in response to the intracellular environment, we screened a library containing fragments of the s. flexneri chromosome fused to a promoterless green fluorescent protein gene (gfp). bacteria containing promoter fusions that had a higher le ... | 2002 | 12117948 |
| molecular cloning and characterization of genes for shigella sonnei form i o polysaccharide: proposed biosynthetic pathway and stable expression in a live salmonella vaccine vector. | the gene region for biosynthesis of shigella sonnei form i o polysaccharide (o-ps) and flanking sequences, totaling >18 kb, was characterized by deletion analysis to define a minimal construct for development of salmonella-based live vaccine vector strains. lipopolysaccharide (lps) expression and dna sequence studies of plasmid deletion derivatives indicated form i o-ps expression from a 12.3-kb region containing a putative promoter and 10 contiguous open reading frames (orfs), one of which is t ... | 2002 | 12117952 |
| [health hazards for immigrants when travelling to their home countries]. | vacations in the home country are important and positive events in the lives of immigrants, events that allow them to maintain contact with their culture, relatives and friends. however, vacations also carry certain health risks, though these risks can to some degree be prevented. infectious disease is the greatest risk. some children and adolescents also run the risk of female genital mutilation, forced marriage, and the risk og being left behind in the home country against their will. among th ... | 2002 | 12119784 |
| clinical dysentery in hospitalized children. | clinical dysentery is a severe presentation of an enteric infection. the aim of the study was to evaluate the impact of a serious bacterial etiology in clinical dysentery in hospitalized children and determine if children at high risk can be identified on the basis of clinical or laboratory parameters. | 2002 | 12120936 |
| [a fatal case of shigellosis in an elderly patient]. | a 71 year-old male, with no recent history of travelling abroad and a past history of lung cancer two years prior to presentation, which had been successfully treated, developed a sudden onset of watery diarrhea more than ten times a day on february 26, 2001, which gradually became bloody. the next day he visited the department of integrated medicine of the tokyo metropolitan komagome hospital by ambulance because his consciousness was deteriorating and he was hospitalized. he was hypotensive on ... | 2002 | 12136656 |
| quadrupole ion-trap mass spectrometry to locate fatty acids on lipid a from gram-negative bacteria. | the structure of lipid a released by mild acid hydrolysis from lipopolysaccharide from two strains of shigella flexneri with different degrees of acylation was characterized using electrospray ionization (esi) and ion-trap mass spectrometry. the lipid a was analyzed underivatized with esi in negative-ion mode. with multiple stages of fragmentation (ms(n)), both the degree of acylation and the positions of the fatty acids on the disaccharide backbone could be determined. it was possible to determ ... | 2002 | 12137789 |
| [comparative analysis of the sensitivity of enterobacteria to bile]. | the analysis of the sensitivity of 195 enterobacterial cultures to bile revealed that their level of resistance decreased in the following row: shigella > salmonella > klebsiella > escherichia > providencia. as shown on a sample of 136 e. coli isolates the level of resistance of these bacteria to bile depended on their isolation source: in e. coli isolated from bile in cholecystitis, from urine in pyelonephritis and from feces in intestinal dysbacteriosis resistance was 1.1-1.3 times higher than ... | 2002 | 12141044 |
| shigellosis linked to sex venues, australia. | from january 1 to july 31, 2000, 148 cases of shigella infection were reported in new south wales, australia, compared with an annual average of 95 cases. of reported cases, 83% were confirmed as shigella sonnei biotype g infections; 80% were in homosexual men. visiting a sex venue in the 2 weeks before onset of illness was the only factor significantly associated with shigellosis. | 2002 | 12141976 |
| mxie regulates intracellular expression of factors secreted by the shigella flexneri 2a type iii secretion system. | the mxi-spa locus on the virulence plasmid of shigella flexneri encodes components of the type iii secretion system. mxie, a gene within this locus, encodes a protein that is homologous to the arac/xyls family of transcriptional regulators, but currently its role in pathogenesis remains undefined. we characterized the virulence phenotype of a nonpolar mxie mutant and found that this mutant retained the ability to invade mammalian cells in tissue culture and secrete ipas (type iii effectors requi ... | 2002 | 12142411 |
| [epidemiological situation of foodborne diseases in santiago, chile in 1999-2000]. | foodborne diseases are becoming an important cause of morbidity in chile. in the metropolitan region of chile, the environmental health service started a surveillance program for foodborne diseases in 1994. in 2000, this program was complemented with an etiologic study of individuals involved in outbreaks. | 2002 | 12143269 |
| rapid detection of six types of bacterial pathogens in marine waters by multiplex pcr. | a rapid multiplex pcr (m-pcr) method that allows the simultaneous detection, in a single tube, of six commonly encountered waterborne pathogens is developed. the target genes used were: the aerolysin (aero) gene of aeromonas hydrophila, the invasion plasmid antigen h (ipah) gene of shigella flexneri, the attachment invasion locus (ail) gene of yersinia enterocolitca, the invasion plasmid antigen b (ipab) gene of salmonella typhimurium, the enterotoxin extracellular secretion protein (epsm) gene ... | 2002 | 12146868 |
| isolation of shigella dysenteriae type 1 and s. flexneri strains from surface waters in bangladesh: comparative molecular analysis of environmental shigella isolates versus clinical strains. | bacillary dysentery caused by shigella species is a public health problem in developing countries including bangladesh. although, shigellae-contaminated food and drinks are often the source of the epidemic's spread, the possible presence of the pathogen and transmission of it through environmental waters have not been adequately examined. we analyzed surface waters collected in dhaka, bangladesh, for the presence of shigellae by a combination of pcr assays followed by concentration and culturing ... | 2002 | 12147489 |
| phylogenetic analysis of salmonella, shigella, and escherichia coli strains on the basis of the gyrb gene sequence. | phylogenetic analysis of about 200 strains of salmonella, shigella, and escherichia coli was carried out using the nucleotide sequence of the gene for dna gyrase b (gyrb), which was determined by directly sequencing pcr fragments. the results establish a new phylogenetic tree for the classification of salmonella, shigella, and escherichia coli in which salmonella forms a cluster separate from but closely related to shigella and e. coli. in comparison with 16s rrna analysis, the gyrb sequences in ... | 2002 | 12149329 |
| comparison of chromagar salmonella medium and xylose-lysine-desoxycholate and salmonella-shigella agars for isolation of salmonella strains from stool samples. | the growth and appearance of 115 stock salmonella isolates on a new formulation of chromagar salmonella (cas) medium were compared to those on xylose-lysine-desoxycholate agar (xld), salmonella-shigella agar (ss), and hektoen enteric agar (hea) media. cas medium was then compared prospectively to xld and ss for the detection and presumptive identification of salmonella strains in 500 consecutive clinical stool samples. all stock salmonella isolates produced typical mauve colonies on cas medium. ... | 2002 | 12149365 |
| bacterial inactivation by high-pressure homogenisation and high hydrostatic pressure. | the resistance of five gram-positive bacteria, enterococcus faecalis, staphylococcus aureus, lactobacillus plantarum, listeria innocua and leuconostoc dextranicum, and six gram-negative bacteria, salmonella enterica serovar typhimurium, shigella flexneri, yersinia enterocolitica, pseudomonas fluorescens and two strains of escherichia coli, to high-pressure homogenisation (100-300 mpa) and to high hydrostatic pressure (200-400 mpa) was compared in this study. within the group of gram-positive bac ... | 2002 | 12160080 |
| street foods in accra, ghana: how safe are they? | to investigate the microbial quality of foods sold on streets of accra and factors predisposing to their contamination. | 2002 | 12163918 |
| characterization of the ysa pathogenicity locus in the chromosome of yersinia enterocolitica and phylogeny analysis of type iii secretion systems. | several gram negative bacteria use a complex system called "type iii secretion system" (ttss) to engage their host. the archetype of ttss is the plasmid-encoded "yop virulon" shared by the three species of pathogenic yersinia (y. pestis, y. pseudotuberculosis, and y. enterocolitica). a second ttss, called ysa (for yersinia secretion apparatus) was recently described in y. enterocolitica 8081, a strain from serotype o:8. in this study, we describe the ysa locus from a127/90, another strain of ser ... | 2002 | 12165841 |
| general outbreaks of infectious intestinal disease linked with salad vegetables and fruit, england and wales, 1992-2000. | between 1992 and 2000, 1,518 foodborne general outbreaks of infectious intestinal disease (iid) were reported to the public health laboratory service (phls) communicable disease surveillance centre (cdsc), of which 83 (5.5%) were associated with the consumption of salad vegetables or fruit (svf). the pathogens most frequently reported were salmonellas (41.0%) and norwalk-like virus (nlv) (15.7%). in total 3,438 people were affected; 69 were admitted to hospital and one person died. most outbreak ... | 2002 | 12166293 |
| identification of a putative pathogenicity island in shigella flexneri using subtractive hybridisation of the s. flexneri and escherichia coli genomes. | the genetic differences between the human pathogen, shigella flexneri, and the non-pathogenic escherichia coli were investigated in an attempt to identify pathogenicity islands (pais) in the s. flexneri genome. genomic subtraction identified a large unique region of dna which was present in s. flexneri serotype 2a but absent from e. coli k-12. this 42-kb dna segment was localised to the s. flexneri chromosome and was found to contain a number of elements often associated with pais including: ins ... | 2002 | 12167547 |
| acid tolerance of shigella sonnei and shigella flexneri. | determination of the behaviour of shigella sonnei and sh. flexneri under acid conditions. | 2002 | 12174047 |
| enteroinvasive escherichia coli virulence-plasmid-carried apyrase (apy) and ospb genes are organized as a bicistronic operon and are subject to differential expression. | in shigella flexneri and enteroinvasive escherichia coli (eiec) the expression of the virulence-plasmid(pinv)-carried potential pathogenesis-associated apy gene, which encodes apyrase (atp diphosphohydrolase), is regulated by the same regulators that govern the expression of virulence genes. to understand the transcriptional organization of the apy gene, the authors sequenced an 8023 bp psti fragment of the pinv of eiec strain hn280, which encompasses apy as well as its adjacent genes. the psti ... | 2002 | 12177345 |
| evolution of multi-gene segments in the muts-rpos intergenic region of salmonella enterica serovar typhimurium lt2. | the nucleotide sequence of the 12.6 kb region between the muts and rpos genes of salmonella enterica serovar typhimurium lt2 (s. typhimurium) was compared to other enteric bacterial muts-rpos intergenic regions. the muts-rpos region is composed of three distinct segments, designated hk, o and s, as defined by sequence similarities to contiguous orfs in other bacteria. inverted chromosomal orientations of each of these segments are found between the muts and rpos genes in related enterobacteriace ... | 2002 | 12177346 |
| shigella: wash your hands of the whole dirty business. | 2002 | 12186178 | |
| characterization of flagella produced by clinical strains of stenotrophomonas maltophilia. | stenotrophomonas maltophilia is an emerging nosocomial pathogen associated with opportunistic infections in patients with cystic fibrosis, cancer, and hiv. adherence of this organism to abiotic surfaces such as medical implants and catheters represents a major risk for hospitalized patients. the adhesive surface factors involved in adherence of these bacteria are largely unknown, and their flagella have not yet been characterized biochemically and antigenically. we purified and characterized the ... | 2002 | 12194767 |
| shigella septicemia. | 2002 | 12196693 | |
| initial steps of shigella infection depend on the cholesterol/sphingolipid raft-mediated cd44-ipab interaction. | shigellosis is an acute inflammatory bowel disease caused by the enteroinvasive bacterium shigella: upon host cell-shigella interaction, major host cell signalling responses are activated. deciphering the initial molecular events is crucial to understanding the infectious process. we identified a molecular complex involving proteins of both the host, cd44 the hyaluronan receptor, and shigella, the invasin ipab, which partitions during infection within specialized membrane microdomains enriched i ... | 2002 | 12198147 |
| geographically separate outbreaks of shigellosis in auckland, new zealand, linked by molecular subtyping to cases returning from samoa. | to investigate simultaneous outbreaks of shigella sonnei gastroenteritis occurring in february 2001 at a health camp for socially deprived children and an elderly care facility. | 2002 | 12199002 |
| sequence analysis and characterization of plasmid psfd10 from salmonella choleraesuis. | the nucleotide sequence of a small plasmid, designated psfd10, is isolated from the vaccine strain salmonella choleraesuis c500 in china, has been determined. this plasmid is 4091 bp long with a total g+c content of 51.4%, which is in the range of salmonella genomic dna. analysis of the complete nucleotide sequence reveals that psfd10 has a high degree of similarity to cole1-type plasmid, having the possible cer and rom genes, and a putative mobilization origin of cole1-type. plasmid psfd10 poss ... | 2002 | 12206756 |
| actin-based phagosome motility. | despite abundant evidence of actin's involvement at the particle internalization stage of phagocytosis, little is known about whether phagosomes undergo the same type of actin-based motility as observed with endocytic vesicles or such intracellular pathogens as listeria and shigella. by employing video microscopy to follow the fate of latex bead-containing phagosomes within the cytoplasm of bone marrow macrophages, we have made the novel observation of actin-based phagosome motility. immunofluor ... | 2002 | 12211106 |
| [outbreak caused by escherichia coli in chalco, mexico]. | to identify the etiologic agent responsible for a disease outbreak following an overflow of sewage water in valle de chalco, mexico. | 2002 | 12216516 |
| [utility of studying feces for the diagnosis and management of infants and preschool children with acute diarrhea]. | to analyze the results of a stool work-up protocol in a series of infants and preschoolers with acute diarrhea. | 2002 | 12216520 |
| three modifications in the d and t arms of trna influence translation in escherichia coli and expression of virulence genes in shigella flexneri. | the modified nucleosides 2'-o-methylguanosine, present at position 18 (gm18), 5-methyluridine, present at position 54 (m(5)u54), and pseudouridine, present at position 55 (psi55), are located in the d and t arms of trnas and are close in space in the three-dimensional (3d) structure of this molecule in the bacterium escherichia coli. the formation of these modified nucleosides is catalyzed by the products of genes trmh (gm18), trma (m(5)u54), and trub (psi55). the combination of trmh, trma, and ... | 2002 | 12218021 |
| polymerase chain reaction detection of invasive shigella and salmonella enterica in food. | 2002 | 11692869 | |
| the immunosuppressive activity of chemically modified lipopolysaccharide of shigella sonnei. | in the present investigations we aimed to study the effect of shigella sonnei lipopolysaccharide (lps) on delayed type hypersensitivity (dth) to non-bacterial antigen in cba mice. these experiments showed that intraperitoneal injection of phenol-water extracted lps and avirulent s. sonnei did not affect the level of dth. however, an injection of avirulent bacteria and lps treated with 2-mercaptoethanol reduced significantly the levels of dth. gel filtration of redox-reactivated lps through sepha ... | 2002 | 11716960 |
| antimicrobial and anti-lipase activity of quercetin and its c2-c16 3-o-acyl-esters. | neither quercetin (q), nor 3-o-acylquercetines, up to 100 microg/ml, had any significant activity on selected gram-positive strains (staphylococcus aureus, bacillus subtilis, listeria ivanovi, listeria monocytogenes, listeria serligeri), gram-negative strains (escherichia coli, shigella flexneri, shigella sonnei, salmonella enteritidis, salmonella tiphymurium) and yeasts (candida albicans and candida glabrata). in addition, we confirmed the known anti-hiv activity of q (80% inhibition at 40 micr ... | 2002 | 11741775 |
| anti-diarrhoeal evaluation of some medicinal plants used by zulu traditional healers. | aqueous and methanolic extracts of several medicinal plants, psidium guajava (leaves), aristea spp., iridaceae family (stem), bridelia micrantha (bark) and eleutherina bulbosa (bulb), used by zulu traditional healers were evaluated for anti-diarrhoeal activity against different experimental models of diarrhoea in rats as well as for anti-microbial activity against different pathogenic microorganisms that cause diarrhoea. the methanolic extract of p. guajava (leaves) was the only agent showing si ... | 2002 | 11744295 |
| in vivo dna-binding and oligomerization properties of the shigella flexneri arac-like transcriptional regulator virf as identified by random and site-specific mutagenesis. | in shigella flexneri expression of the plasmid-encoded virulence genes is regulated via a complex mechanism involving both environmental signals and specific transactivators. the primary regulator protein, virf, is a member of the arac family of transcription factors and shares with other arac-like proteins a conserved carboxy-terminal domain thought to be important for dna binding. random and site-directed mutagenesis of the virf gene encoding virf yielded a number of mutations along the length ... | 2002 | 11751832 |
| high frequency of mutator strains among human uropathogenic escherichia coli isolates. | by using a panel of 603 commensal and pathogenic escherichia coli and shigella isolates, we showed that mutation rates of strains vary considerably among different ecotypes. uropathogenic strains had the highest frequency of mutators, while strains from patients with bacteremia had the lowest mutation rates. no correlation between the mutation rates and antibiotic resistance was observed among the studied strains. | 2002 | 11751844 |
| identification of enteric pathogens by heat shock protein 60 kda (hsp60) gene sequences. | a highly specific and reproducible approach for the simultaneous detection of enteric pathogenic bacteria was developed using bacterial hsp60 gene and molecular biological tools. a single pair of universal primers was derived from the highly conserved sequence of hsp60 genes encompassing a 600-bp hypervariable region. pcr amplification followed by either dot blot hybridization or restriction enzyme digestion performed on 38 enteric bacteria indicated that this approach could differentiate not on ... | 2002 | 11786265 |
| from the centers for disease control and prevention. shigella sonnei outbreak among men who have sex with men--san francisco, california, 2000-2001. | 2002 | 11797625 |