[pseudotuberculosis and yersiniosis in man]. 1979388709
[the isolation of two of yersina pseudotuberculosis from wild animals in different regions of turkey].two strains of yersinia pseudotuberculosis were isolated from wild animals collected from different regions in anatolia. skin test with y. pseudotuberculosis antigen on human subjects in various parts of turkey gave a high percentage of positive results. it seems probable that this microorganism can cause infections in man transmitted by wild animals.1976790105
[pathoanatomical characteristics of pseudotuberculosis in macaca mulatta].pathologo-anatomic investigations of organs of 81 monkeys who had died of pseudotuberculosis were carried out. the disease was characterized by pronounced polymorphism of changes with predominant lesions of the peritoneal cavity organs--the spleen, liver, intestinal and mesenterial lymphatic nodes. granulomas appeared consisting of reticular cells with admixture of neurophilic, eosinophilic leucocytes with necrosis in the centre. pseudotuberculosis in monkeys, as to its clinical and patho-anatom ...1976828491
terminal ileitis, mesenteric lymphadenitis and appendicitis due to yersinia pseudotuberculosis type va: case report.a case of terminal ileitis, mesenteric lymphadenitis and appendicitis is reported. serological studies indicated infection with yersinia pseudotuberculosis type va. the patient's illness ran a chronic course necessitating resection of the terminal ileum. histological examination of the appendix and a mesenteric lymph node in the acute stage revealed granulomas with central necrosis. this is the first human case in which the subtype va has been identified.19761004946
[bacteria of the yersinia genus in human pathology]. 19751101314
lcrf is the temperature-regulated activator of the yada gene of yersinia enterocolitica and yersinia pseudotuberculosis.the virulence plasmid of human pathogenic yersinia species, pyv, encodes secreted proteins, yop proteins, and an outer membrane protein, yada. yada has been associated with binding to a variety of substrates and with interference with host defense. yada is regulated by temperature and is expressed only at 37 degrees c. unlike the yop regulon, the yada gene is not under ca2+ regulation. here, we show that lcrf (virf), the temperature-regulated activator of the yop regulon, also acts as an activat ...19921548243
epizootic of yersinia pseudotuberculosis in a wildlife epizootic attributable to yersinia pseudotuberculosis infection was confirmed in captive ruminants in a wildlife park by microbiologic and histologic findings. an epornitic of y pseudotuberculosis infection was identified at the same period in a vicinity near the ruminant deaths. yersinia pseudotuberculosis can infect human beings and cause acute enteritis and mesenteric lymphadenitis. people in contact with infected animals should use extreme caution and use good sanitary precautions to prec ...19921644638
[functional state of thrombocytes in yersinia infection].as many as 94 patients with yersiniosis were examined for the morphofunctional status of platelets (aggregation, disaggregation, endo-exocytosis and platelet forms). the data indicate that platelet from patients with yersiniosis possess a high ability for aggregation and a low ability for disaggregation. according to the experimental and clinical data, emoxipine can restore disturbed function of human platelets.19911801465
[enteropathogenic yersinias: pathogenicity factors and new diagnostic methods].a limited number of serotypes of yersinia enterocolitica and y. pseudotuberculosis is enteropathogenic for humans. during the last decade molecular biology contributed significantly to the understanding of the pathogenicity of these enteric agents. all human pathogenic yersiniae harbour a 70-kilobase plasmid which is essential for virulence expression. presently, thirteen plasmid-encoded polypeptides have been identified. two of them have been identified as true outer membrane proteins and at le ...19902076901
seasonal patterns of rodents, fleas and plague status in the western usambara mountains, tanzania.field and commensal rodents were live-trapped at three villages in an active focus of plague (yersinia pseudotuberculosis pestis) in lushoto district, western usambara mountains, tanga region, tanzania, from december 1983 to november 1984. their flea ectoparasites were collected, identified and counted. the rodent carcasses were serologically examined for specific plague antibodies and antigens, and bacteriologically examined for bipolar staining bacilli. a total of 1758 traps were set during th ...19892519642
[clinical aspects of yersinia pseudotuberculosis infections].during 2 years 27 cases of yersinia pseudotuberculosis infections were diagnosed in the infectious ward. on the basis of literary data and her own cases the author discusses in details the clinical aspects and varying forms of yersinia pseudotuberculosis infections. the attention is drawn to the fact that the pathogen is widespread, to the incidence of human infections and to the difficulties of differential diagnostics.19892689952
virulence-plasmid is associated with the inhibition of opsonization in yersinia enterocolitica and yersinia pseudotuberculosis.plasmid-cured variants of virulent strains of yersinia enterocolitica and y. pseudotuberculosis were obtained by selection after growth in calcium-deficient medium. to obtain antigen preparations consisting of whole bacteria the original plasmid-containing strains and the plasmid-cured variants were grown in conditions favouring expression of the temperature-inducible outer membrane proteins of yersinia (yop) (37 degrees c, calcium-deficient culture medium). the presence or absence of the yop on ...19873652518
temperature-inducible surface fibrillae associated with the virulence plasmid of yersinia enterocolitica and yersinia pseudotuberculosis.when cultivated at 37 degrees c in static broth, human clinical isolates of yersinia enterocolitica (serogroups o:3, o:8, and o:9) and yersinia pseudotuberculosis (serogroup o:iii) produced numerous nonflagellar surface appendages, which appeared as a lawn of fine fibrillae, each having a diameter of 1.5 to 2.0 nm and a length of 50 to 70 nm. cultivation at 22 degrees c resulted in complete disappearance of the fibrillae. the phenotypic expression of these appendages was correlated with the pres ...19853881355
[human infection caused by yersinia pseudotuberculosis (malassez and vignal bacillus) and yersinia enterocolitica]. 19695380346
[the place of anatomo-pathological study in the diagnosis of enterocolitis complicated by yersinia pseudo-tuberculosis].over a period of 3 months, 3 patients were operated on for subacute enterocolitis. the first case was a 3 years old boy with a transverse colonic perforation near the right angle and gross lymphadenopathy. the second case was a 21 years old man who had subacute terminal ileitis. histopathological study showed specific lesions in those two cases: ovoïd or starry abscesses with preepithelioïd cells, rare giant langhans cells, rare altered polynuclear cells in necrosis, massive lymphoïd hyperplasia ...19836365109
some aspects of the immunology of pseudotuberculosis.integral evaluation of some humoral and cellular immunity factors in patients with pseudotuberculosis (far-east scarlatinoid fever) with varying severity of its course was carried out. inadequate immune reaction of human organism in response to infection with pseudotuberculosis was established at the level of both specific (sporadic cases of lacking synthesis or poor synthesis of igm antibodies, lacking synthesis of igg antibodies) and non-specific factors (incomplete phagocytic reaction). phago ...19826754810
[human infection by yersinia enterocolitica and pseudotuberculosis in spain. analysis of 80 recent cases]. 19817025130
[cellular reactions of increased delayed sensitivity in human pseudotuberculosis].a total of 145 patients having far eastern scarlatiniform fever, 99 healthy persons and 54 patients with diseases of non-pseudotuberculous etiology have been examined by means of fradkin's neutrophil damage test, the capillary cell migration inhibition test and the intradermal test. the specific transformation of the cellular immunity system has been shown to occur in scarlatiniform fever. this transformation takes the form of delayed type hypersensitivity reaction. the immunological tests used ...19827043971
[seasonal isolation of yersinia enterocolitica and yersinia pseudotuberculosis from tonsils of healthy slaughter pigs (author's transl)].45 strains of yersinia (y.) enterocolitica from which 36 respectively 9 belonged to o-group i or v and 28 strains of y. pseudotuberculosis from which 15 respectively 13 isolates belonged to serotype i or ii were isolated from 70 tonsils of 480 examined, clinically healthy slaughter pigs. in the tonsils of three animals were found both species together. y. enterocolitica was isolated during the whole year, but especially in the months of november (17.5%) and december (32.5%). y. pseudotuberculosi ...19817198363
dna sequencing of the gene encoding a bacterial superantigen, yersinia pseudotuberculosis-derived mitogen (ypm), and characterization of the gene product, cloned ypm.previously, we found a novel bacterial superantigen from yersinia pseudotuberculosis, designated y. pseudotuberculosis-derived mitogen (ypm). in the present study, we analyzed the dna sequence of the gene encoding ypm. the ypm gene was cloned into a plasmid vector pmw119 and expressed in escherichia coli dh10b. like the native ypm, the cloned ypm required the expression of mhc class ii molecules on accessory cells in the induction of il-2 production by human t cells. tcr-v beta repertoire of hum ...19957730627
differential integrin expression facilitates isolation of human fetal pancreatic epithelial cells.we have studied the expression of the beta 1 family of integrins in fetal and adult human pancreas. immunohistochemical staining with a monoclonal anti-beta 1 antibody revealed that the epithelial cells of the human fetal pancreas express high amounts of beta 1 integrin, while the pancreatic stromal cells express substantially lower amounts. islets of langerhans from human adult pancreas also expressed high amounts of beta 1 integrin. taking advantage of the extremely high affinity binding betwe ...19947921635
purification and characterization of a novel superantigen produced by a clinical isolate of yersinia pseudotuberculosis.a superantigen designated as yersinia pseudotuberculosis-derived mitogen (ypm) was purified in an equal manner from both the culture supernatant and cell lysate of a clinical isolate (kur-1) of y. pseudotuberculosis serotype 4b. a significant proliferative response of human peripheral blood mononuclear cells to purified ypm was detectable even at a concentration of 1 pg/ml. the n-terminal sequence of ypm which included 23 amino acid residues was determined, by automated edman degradation, as thr ...19947988709
[an analysis of the antibodies to the outer cell membrane proteins in yersinia in the varying course of human pseudotuberculosis].time course changes in the formation and spectrum of the antibodies to the proteins of yersinia pseudotuberculosis external cellular membrane were studied by immunoblotting. a total of 154 samples of blood serum from 46 pseudotuberculosis (pt) patients were tested. 53 samples were obtained from pt patients with acute disease, 50 from pt patients with recurrences and 51 samples cam from pt subjects with protracted disease. electrophoresis in polyacrylamide gel with sodium dodecyl sulfate disclose ...19948016734
comparison of siderophore production and utilization in pathogenic and environmental isolates of yersinia enterocolitica.yersinia enterocolitica strains of serotypes lethal to mice have been reported previously to produce an endogenous siderophore. in this study, an ethyl acetate-extractable siderophore was characterized and given the name yersiniophore. yersiniophore was produced by 16 of 16 human isolates of serotypes o:4, o:4,32, o:8, o:21, and one nonhuman isolate of serotype o:21. it was not produced by isolates of serotype o:3, o:5, or o:9. one strain of yersinia pseudotuberculosis produced yersiniophore, bu ...19948126201
bacterial and viral protein tyrosine phosphatases.unrestricted protein tyrosine phosphatase (ptpase) activity may play a role in pathogenesis. for instance, the virulence determinant gene, yoph, of yersinia pseudotuberculosis encodes a ptpase. the phosphatase activity of the yoph protein is essential for the pathogenesis of y. pseudotuberculosis. yersinia pestis, the bacterium which causes the bubonic plague, also contains a gene closely related to yoph. the action of yoph on host proteins appears to break down signal transduction mechanisms in ...19938305677
yersinia pseudotuberculosis in italy. attempted recovery from 37,666 samples.from 1981 to 1991, 37,666 human, animal, food and environmental samples were cultured for yersinia pseudotuberculosis using direct plating methods and/or cold enhancement techniques. despite an intensive surveillance and adequate culture methods, y. pseudotuberculosis was isolated from stools of 0.05% (5/9,720) of patients with acute enteritis, and alimentary tracts of 0.1% (10/6,849) of apparently healthy animals. no y. pseudotuberculosis strains were recovered from stools of 4,726 health contr ...19938355621
population genetics of human, animal, and environmental yersinia strains.multilocus enzyme electrophoresis was used to analyze 244 strains of nine yersinia species isolated from the environment, animals, and humans at 18 genes encoding metabolic enzymes. all 18 enzymes were polymorphic. among the 137 electrophoretic types (ets) distinguished, the mean allelic diversity per locus was 0.531. yersinia frederiksenii ets were divided into three major clusters that were separated by a large genetic distance, and one et was more closely related to yersinia enterocolitica. t ...19938434911
identification of murine t cells reactive with the bacterial superantigen yersinia pseudotuberculosis-derived mitogen (ypm) and factors involved in ypm-induced toxicity in mice.we previously reported that yersinia pseudotuberculosis-derived mitogen (ypm) acts as a superantigen to human t cells. in this study, we assessed the superantigenicity and toxicity of ypm using murine experimental models. ypm activated t cells to produce interleukin-2 in a major histocompatibility complex class ii molecule-dependent manner. the t-cell blasts induced by ypm expressed t-cell receptor (tcr) beta-chain variable region (vbeta)7, vbeta8.1, vbeta8.2 and vbeta8.3. the injection of ypm i ...19979159409
yersinia invasin, a bacterial beta1-integrin ligand, is a potent inducer of lymphocyte motility and migration to collagen type iv and fibronectin.the yersinia pseudotuberculosis invasin protein was found to be a potent inducer of pseudopodia formation and chemotactic and haptotactic migration in human t lymphocytes. checkerboard analysis confirmed that migration was directional. the yersinia invasin triggered migration of otherwise poorly migratory normal t cells on fibronectin and in particular on collagen type iv, and augmented the migration of leukemic t cell lines on these components. invasin-induced lymphocyte migration was inhibited ...19979257849
purification, characterization and cloning of a novel variant of the superantigen yersinia pseudotuberculosis-derived mitogen.the novel superantigen designated as yersinia pseudotuberculosis-derived mitogen typeb (ypmb) was purified from the cell lysate of y. pseudotuberculosis o:6 strain (r-104). proliferative response of human peripheral blood mononuclear cells to the purified ypmb was detectable at a concentration of as low as 1 pg/ml, that is comparable to the previously documented ypm (ypma). the vbeta repertoire specificity (3, 9, 13.1 and 13.2) of ypmb was also the same as that of ypma. a gene (ypmb) encoding yp ...19979287138
bubonic plague: a molecular genetic case history of the emergence of an infectious disease.yersinia pestis, the bacterial agent of bubonic plague, is transmitted primarily by fleas and has been responsible for devastating epidemics throughout history. y. pseudotuberculosis is a food- and water-borne pathogen that causes a much more benign enteric disease in humans. despite these profoundly different pathogenesis strategies, the two bacteria are very closely related phylogenetically. thus, identifying the specific genetic differences between them should provide an instructive case stud ...19979351703
a complex composed of sycn and yscb functions as a specific chaperone for yopn in yersinia pestis.human pathogenic yersinia resist host defences, in part through the expression and delivery of a set of plasmid-encoded virulence proteins termed yops. a number of these yops are exported from the bacteria directly into the cytoplasm of their eukaryotic host's cells upon contact with these cells. the secreted yopn protein (also known as lcre) is required to block yop secretion in the presence of calcium in vitro or before contact with a eukaryotic cell in vivo. in this study, we characterize the ...199810094626
yersinia pseudotuberculosis-induced calcium signaling in neutrophils is blocked by the virulence effector yoph.pathogenic species of the genus yersinia evade the bactericidal functions of phagocytes. this evasion is mediated through their virulence effectors, yops, which act within target cells. in this study we investigated the effect of yersinia pseudotuberculosis on ca2+ signaling in polymorphonuclear neutrophils. the intracellular free calcium concentration in single adherent human neutrophils was monitored during bacterial infection and, in parallel, the encounter between the bacteria and cells was ...199910225922
cytotoxic t-cell-mediated response against yersinia pseudotuberculosis in hla-b27 transgenic rat.yersinia-induced reactive arthritis is highly associated with hla-b27, the role of which in defense against the triggering bacteria remains unclear. the aim of this study was to examine the capacity of rats transgenic for hla-b27 to mount a cytotoxic t-lymphocyte (ctl) response against y. pseudotuberculosis and to determine the influence of the hla-b27 transgene on this response. rats transgenic for hla-b*2705 and human beta(2)-microglobulin of the 21-4l line, which do not spontaneously develop ...199910417137
inhibition of the mitogen-activated protein kinase kinase superfamily by a yersinia effector.the bacterial pathogen yersinia uses a type iii secretion system to inject several virulence factors into target cells. one of the yersinia virulence factors, yopj, was shown to bind directly to the superfamily of mapk (mitogen-activated protein kinase) kinases (mkks) blocking both phosphorylation and subsequent activation of the mkks. these results explain the diverse activities of yopj in inhibiting the extracellular signal-regulated kinase, c-jun amino-terminal kinase, p38, and nuclear factor ...199910489373
infection of human enterocyte-like cells with rotavirus enhances invasiveness of yersinia enterocolitica and y. pseudotuberculosis.mixed infection with rotavirus and either yersinia enterocolitica or y. pseudotuberculosis was analysed in caco-2 cells, an enterocyte-like cell line highly susceptible to these pathogens. results showed an increase of bacterial adhesion and internalisation in rotavirus-infected cells. increased internalisation was also seen with escherichia coli strain hb101 (pri203), harbouring the inv gene from y. pseudotuberculosis, which is involved in the invasion process of host cells. in contrast, the su ...200011023186
expression of random peptide fused to invasin on bacterial cell surface for selection of cell-targeting peptides.the protein invasin expressed on the cell surface of the pathogenic bacteria yersinia pseudotuberculosis mediates the entry of this bacterium into cultured mammalian cells. we have developed a system for expression of random peptides on the cell surface of escherichia coli (e. coli) by creation of a fusion hybrid between a peptide and the invasin protein. the fusion protein constructs consist of part of the outer membrane domain of the invasin protein, six proline spacers, and a decamer of rando ...200011137298
genome sequence of yersinia pestis, the causative agent of plague.the gram-negative bacterium yersinia pestis is the causative agent of the systemic invasive infectious disease classically referred to as plague, and has been responsible for three human pandemics: the justinian plague (sixth to eighth centuries), the black death (fourteenth to nineteenth centuries) and modern plague (nineteenth century to the present day). the recent identification of strains resistant to multiple drugs and the potential use of y. pestis as an agent of biological warfare mean t ...200111586360
efficient uptake of yersinia pseudotuberculosis via integrin receptors involves a rac1-arp 2/3 pathway that bypasses n-wasp function.efficient uptake of yersinia pseudotuberculosis into cultured mammalian cells is the result of high-affinity binding of invasin to beta1 chain integrins. we demonstrate here that uptake requires rac1 and arp 2/3 function. bacterial uptake was stimulated by gtpgammas, but was inhibited in mammalian cells transfected with the interfering rac1-n17 derivative. rac1 was found to be activated in response to integrin engagement by invasin, whereas rac1 and arp 2/3 were found to be intensely localized a ...200111722735
interaction of yersinia enterocolitica and y. pseudotuberculosis with platelets.yersinia enterocolitica is a bacterium capable of growth at 4 degrees c in donated blood and has been responsible for many deaths following transfusion. interaction of y. enterocolitica with blood cells is of interest in understanding the mechanisms of survival and growth in blood. the closely related organism y. pseudotuberculosis is known to invade platelets and cause platelet aggregation by a mechanism that involves expression of the chromosomal inv gene. yersinia isolates were made to expres ...200111761186
the yada protein of yersinia pseudotuberculosis mediates high-efficiency uptake into human cells under environmental conditions in which invasin is repressed.the yada protein is a major adhesin of yersinia pseudotuberculosis that promotes tight adhesion to mammalian cells by binding to extracellular matrix proteins. in this study, we first addressed the possibility of competitive interference of yada and the major invasive factor invasin and found that expression of yada in the presence of invasin affected neither the export nor the function of invasin in the outer membrane. furthermore, expression of yada promoted both bacterial adhesion and high-ef ...200212183532
crystal structure of a major secreted protein of mycobacterium tuberculosis-mpt63 at 1.5-a resolution.mpt63 is a small, major secreted protein of unknown function from mycobacterium tuberculosis that has been shown to have immunogenic properties and has been implicated in virulence. a blast search identified that mpt63 has homologs only in other mycobacteria, and is therefore mycobacteria specific. as mpt63 is a secreted protein, mycobacteria specific, and implicated in virulence, mpt63 is an attractive drug target against the deadliest infectious disease, tuberculosis (tb). as part of the tb st ...200212441386
microtubule-dependent regulation of rho gtpases during internalisation of yersinia pseudotuberculosis.internalisation of the human pathogen yersinia pseudotuberculosis via interaction of bacterial invasin with host beta1 integrins depends on the actin cytoskeleton and involves src family kinases, focal adhesion kinase, p130crk-associated substrate, proline-rich tyrosine kinase 2, rac, arp 2/3 complex and wasp family members. we show here that rho gtpases are regulated by the microtubule system during bacterial uptake. interfering with microtubule organisation using nocodazole or paclitaxel suppr ...200312505155
[mode of sample preparation for pseudotuberculosis laboratory diagnosis by polymer chain reaction method].a mode of feces sample preparation was developed for polymerase chain reaction (pcr) assay. it was based on alkaline treatment of the material. this treatment killed the most part of indigenous microflora, whereas yersinia survived, because it was relatively resistant to alkaline. the mode was tested using human feces artificially contaminated with yersinia pseudotuberculosis. positive responses in samples containing 10(3)-10(8) microbial cells per ml were obtained by pcr assay with yersi and ye ...200212534270
interaction between the yersinia protein tyrosine phosphatase yoph and eukaryotic cas/fyb is an important virulence mechanism.the tyrosine phosphatase yoph is an essential virulence factor produced by pathogenic yersinia species. yoph is translocated into host cells via a type iii secretion system and its dephosphorylating activity causes disruption of focal complex structures and blockage of the phagocytic process. among the host cell targets of yoph are the focal adhesion proteins crk-associated substrate (p130cas) and focal adhesion kinase (fak) in epithelial cells, and p130cas and fyn-binding protein (fyb) in macro ...200312542470
pathogenic yersinia enterocolitica strains increase the outer membrane permeability in response to environmental stimuli by modulating lipopolysaccharide fluidity and lipid a structure.pathogenic biotypes of yersinia enterocolitica (serotypes o:3, o:8, o:9, and o:13), but not environmental biotypes (serotypes o:5, o:6, o:7,8, and o:7,8,13,19), increased their permeability to hydrophobic probes when they were grown at ph 5.5 or in egta-supplemented (ca(2+)-restricted) media at 37 degrees c. a similar observation was also made when representative strains of serotypes o:8 and o:5 were tested after brief contact with human monocytes. the increase in permeability was independent of ...200312654821
isolation and expression of recombinant antibody fragments to the biological warfare pathogen brucella melitensis.brucella melitensis is a highly infectious animal pathogen able to cause a recurring debilitating disease in humans and is therefore high on the list of biological warfare agents. immunoglobulin genes from mice immunized with gamma-irradiated b. melitensis strain 16m were used to construct a library that was screened by phage display against similarly prepared bacteria. the selected phage particles afforded a strong enzyme-linked immunosorbent assay (elisa) signal against gamma-irradiated b. mel ...200312738372
[virulence of yersinia pseudotuberculosis strains isolated from environment as a threat to human epidemic].the purpose of the work has been to identify yersinia pseudotuberculosis strains and to demonstrate their potential pathogenicity using pcr reaction. investigations included 167 samples of the water and 32 samples of the soil from westpomeranian region. based on the analysis of pcr reactions the research confirmed the presence of dna y. pseudotuberculosis strain in 6 of the water samples and in 1 of the soil sample. the strains have been identified by nucleotide sequence of the ypm gene, which i ...200312910593
pasteurella pseudotuberculosis antibody titres in man: a preliminary report. 196213907843
[human infections with pasteurella pseudotuberculosis serologically confirmed]. 196414250948
[pasteurella pseudotuberculosis as the pathogen of a human pseudo-appendicitis]. 196014417120
[on the epidemiology of pasteurella pseudotuberculosis infection in man]. 196214471487
[development of a competitive immunoassay based on monoclonal antibodies for the detection of specific antibodies to pseudotuberculosis pathogen].a highly sensitive, effective and rapid method--a competitive alternative to elisa--was developed for the detection of specific antibodies to y. pseudotuberculosis. it is based on monoclonal antibodies (mabs) recognizing the species- or serogroup specific epitopes of y. pseudotuberculosis. the competitive elisa was used in testing the murine hyperimmune sera and human antisera sampled from patients with different infectious intestinal diseases including several cases of pseudotuberculosis. the u ...200314708373
identification of novel virulence-associated genes via genome analysis of hypothetical genes.the sequencing of bacterial genomes has opened new perspectives for identification of targets for treatment of infectious diseases. we have identified a set of novel virulence-associated genes (vag genes) by comparing the genome sequences of six human pathogens that are known to cause persistent or chronic infections in humans: yersinia pestis, neisseria gonorrhoeae, helicobacter pylori, borrelia burgdorferi, streptococcus pneumoniae, and treponema pallidum. this comparison was limited to genes ...200414977936
critical role of t cell migration in bacterial superantigen-mediated shock in mice.bacterial superantigens have been implicated in the pathogenesis of several human diseases. among them, toxic shock syndrome (tss) is a prototypic acute intoxication caused by the pyrogenic exotoxin family of superantigens. in this study, we investigated the pathophysiological mechanism of tss using the yersinia pseudotuberculosis-derived mitogen (ypm) and its point mutants. the results indicated that ypm could induce toxic shock in balb/c mice but not in t cell-deficient scid mice. we found tha ...200415003813
the recent emergence of plague: a process of felonious evolution.yersinia pestis, the causative agent of bubonic plague, evolved from closely related yersinia pseudotuberculosis within the past 20,000 years, an event that corresponds to the end of the last ice age and distribution of homo sapiens throughout the world. y. pseudotuberculosis causes chronic but generally mild enteropathogenic infections whereas plague is the most devastating acute disease experienced by mankind. the very recent evolution of plague from its progenitor assures close genomic homoge ...200415037962
use of florfenicol in non-human primates.studies were undertaken to determine if florfenicol, an antimicrobial agent structurally similar to chloramphenicol, could be used as an effective broad spectrum antibiotic for the treatment of bacterial infections in primates. florfenicol was developed as an injectable antibiotic for use in cattle on an every other day dosing schedule. its broad spectrum activity, long duration of action following i.m. administration, and its safety as compared with chloramphenicol made it an attractive antibio ...200415102069
age influences resistance of caenorhabditis elegans to killing by pathogenic bacteria.caenorhabditis elegans has previously been proposed as an alternative host for models of infectious disease caused by human pathogens. when exposed to some human pathogenic bacteria, the life span of nematodes is significantly reduced. we have shown that mutations in the age-1, and/or age-2 genes of c. elegans, that normally enhance life expectancy, can also increase resistance to killing by the bacterial pathogens pseudomonas aeruginosa, salmonella enterica var. typhimurium, burkholderia cepaci ...200415135534
microevolution and history of the plague bacillus, yersinia pestis.the association of historical plague pandemics with yersinia pestis remains controversial, partly because the evolutionary history of this largely monomorphic bacterium was unknown. the microevolution of y. pestis was therefore investigated by three different multilocus molecular methods, targeting genomewide synonymous snps, variation in number of tandem repeats, and insertion of is100 insertion elements. eight populations were recognized by the three methods, and we propose an evolutionary tre ...200415598742
a novel semiquantitative fluorescence-based multiplex polymerase chain reaction assay for rapid simultaneous detection of bacterial and parasitic pathogens from blood.a multiplex polymerase chain reaction assay was developed for the rapid simultaneous detection of category a select bacterial agents (bacillus anthracis and yersinia pestis) and parasitic pathogens (leishmania species) in blood using the cepheid smart cycler platform. b. anthracis (sterne) and yersinia. pseudotuberculosis were used in the assay for optimization for b. anthracis and y. pestis, respectively. the specificity of the target amplicons [protective antigen gene of b. anthracis and rrna ...200515858151
inhibition of mapk and nf-kappa b pathways is necessary for rapid apoptosis in macrophages infected with yersinia.macrophages respond to infection with pathogenic yersinia species by activating mapk- and nf-kappab-signaling pathways. to counteract this response, yersiniae secrete a protease (yersinia outer protein j (yopj)) that is delivered into macrophages, deactivates mapk- and nf-kappab-signaling pathways, and induces apoptosis. nf-kappab promotes cell survival by up-regulating expression of several apoptosis inhibitor genes. previous studies show that deactivation of the nf-kappab pathway by yopj is im ...200515944300
the comparative importance of e. coli antigen in granulomatous colitis of boxer dogs.granulomatous colitis of boxer dogs is characterized by mucosal and submucosal infiltration by abundant large macrophages and lymphocytes and plasma cells. involved intestine is thickened, corrugated and ulcerated. the macrophages that occur in colon, cecum and regional lymph nodes are pas-positive, lipid-rich, contain cholesterol, and some of the time can be seen to hold bacteria. paraffin tissue blocks of formalin-fixed colon and colic lymph nodes from 10 cases were cut at 5 microm and immunos ...200515996159
clpv, a unique hsp100/clp member of pathogenic proteobacteria.hsp100/clp proteins are key players in the protein quality control network of prokaryotic cells and function in the degradation and refolding of misfolded or aggregated proteins. here we report the identification of a new class of hsp100/clp proteins, termed clpv (virulent strain), that are present in bacteria interacting with eukaryotic cells, including human pathogens. the clpv proteins are most similar to clpb proteins within the hsp100/clp family, but cluster in a separate phylogenetic tree ...200516307477
the serodiagnosis of human infections with yersinia enterocolitica and yersinia pseudotuberculosis.the techniques of sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page) and immunoblotting were evaluated for the serodiagnosis of human infections with yersinia enterocolitica and yersinia pseudotuberculosis. lipopolysaccharide (lps) was prepared from strains comprising four serogroups of y. enterocolitica and five serogroups of y. pseudotuberculosis, tested against 200 sera submitted to the laboratory of enteric pathogens for routine serodiagnosis, and shown to contain antibodie ...200616872375
yersinia pseudotuberculosis superantigens.yersinia pseudotuberculosis, a gastro-intestinal bacterium, produces three closely related t cell superantigens, ypma, ypmb and ypmc, which have no significant sequence similarity to other proteins, let alone other bacterial superantigens. y. pseudotuberculosisderived mitogen (ypm) has been shown to play a role in the pathogenesis of human and animal y. pseudotuberculosis infection. the three-dimensional structure of ypma, as determined by x-ray crystallography and nuclear magnetic resonance spe ...200717369701
how the structural gene products of yersinia pestis relate to virulence.bubonic plague is the most devastating acute infectious disease known to man. the causative agent, yersinia pestis, is now more firmly entrenched in sylvatic reservoirs throughout the world than at any time in the past. consequently, the organism increasingly causes casual human disease and is readily available for use as a bioweapon. recent attempts to understand the severe nature of plague have focused upon its very recent divergence from yersinia pseudotuberculosis, an etiological instrument ...200717683274
the importance of the rcs phosphorelay in the survival and pathogenesis of the enteropathogenic yersiniae.the human-pathogenic yersiniae represent an ideal species group to study the evolution of highly virulent bacteria, with yersinia pestis having emerged from the enteropathogen y. pseudotuberculosis an estimated 20 000 years ago. sequence data reveal that the y. pestis genome is in the early stages of decay and contains hundreds of non-functioning pseudogenes, some of which may be important in the enteric lifestyle of y. pseudotuberculosis. bioinformatic analysis of pseudogenes from seven y. pest ...200818375804
yersinia pseudotuberculosis induces transcytosis of nanoparticles across human intestinal villus epithelium via invasin-dependent macropinocytosis.crohn's disease is characterized by a defect in intestinal barrier function, where bacteria are considered the most important inflammation-driving factor. enteric bacteria, including e. coli and yersinia spp, affect tight junctions in enterocytes, but little is known about bacterial effects on the transcellular pathway. our objective was to study the short-term effects of y. pseudotuberculosis on uptake of nanoparticles across human villus epithelium. monolayers of human colon epithelium-derived ...200818810251
[modulating effect of serotonin on the development of human leukocytes apoptosis induced by yersinia].effect of biogenic amine serotonin on the development of human blood leukocytes during interaction with species from yersinia genus (y. pestis ev, y. pseudotuberculosis serovars i and iv, y. enterocolitica serovars 09 and 03) was studied in model system in vitro using flow cytofluorometry. serotonin in concentration 10(-5) m had differently marked effects on yersinia spp.-induced apoptosis of leukocytes. pattern of the observed changes depended from species and serovar of yersinia. serotonin inh ...200819186545
prevalence of enteropathogenic yersinia in estonian, latvian, and russian (leningrad region) pigs.tonsils of 457 fattening pigs from estonia (n = 151), latvia (n = 109), and the leningrad region of russia (n = 197) were collected between 2004 and 2007 to study the prevalence of enteropathogenic yersinia in slaughter pigs. yersinia enterocolitica and yersinia pseudotuberculosis were isolated by selective and cold enrichment. pathogenic y. enterocolitica and y. pseudotuberculosis were identified by pcr targeting the chromosomal genes ail and inv, respectively. the presence of the virulence pla ...200919580449
yersinia outer protein yope affects the actin cytoskeleton in dictyostelium discoideum through targeting of multiple rho family gtpases.all human pathogenic yersinia species share a virulence-associated type iii secretion system that translocates yersinia effector proteins into host cells to counteract infection-induced signaling responses and prevent phagocytosis. dictyostelium discoideum has been recently used to study the effects of bacterial virulence factors produced by internalized pathogens. in this study we explored the potential of dictyostelium as model organism for analyzing the effects of ectopically expressed yersin ...200919602247
typing methods for the plague pathogen, yersinia pestis.phenotypic and genotypic methodologies have been used to differentiate the etiological agent of plague, yersinia pestis. historically, phenotypic methods were used to place isolates into one of three biovars based on nitrate reduction and glycerol fermentation. classification of y. pestis into genetic subtypes is problematic due to the relative monomorphic nature of the pathogen. resolution into groups is dependent on the number and types of loci used in the analysis. the last 5-10 years of rese ...200919714987
superantigen-presentation by rat major histocompatibility complex class ii molecules and rt1.dl.rat major histocompatibility complex (mhc) class ii molecules rt1.b(l) (dq-like) and rt1.d(l) (dr-like) were cloned from the lew strain using reverse transcription-polymerase chain reaction and expressed in mouse l929 cells. the transduced lines bound mhc class ii-specific monoclonal antibodies in an mhc-isotype-specific manner and presented peptide antigens and superantigens to t-cell hybridomas. the t-cell-hybridomas responded well to all superantigens presented by human mhc class ii, whereas ...200919740318
interaction of yersinia with the gut: mechanisms of pathogenesis and immune evasion.yersinia entercolitica and yersinia pseudotuberculosis are human foodborne pathogens that interact extensively with tissues of the gut and the host's immune system to cause disease. as part of their pathogenic strategies, the yersinia have evolved numerous ways to invade host tissues, gain essential nutrients, and evade host immunity. technological advances over the last 10 years have revolutionized our understanding of host-pathogen interactions. the application of these new technologies has al ...200919812980
steps toward broad-spectrum therapeutics: discovering virulence-associated genes present in diverse human and improved antimicrobial countermeasures are urgently needed to counteract increased resistance to existing antimicrobial treatments and to combat currently untreatable or new emerging infectious diseases. we demonstrate that computational comparative genomics, together with experimental screening, can identify potential generic (i.e., conserved across multiple pathogen species) and novel virulence-associated genes that may serve as targets for broad-spectrum countermeasures.200919874620
recent findings regarding maintenance of enzootic variants of yersinia pestis in sylvatic reservoirs and their significance in the evolution of epidemic plague.despite the widespread presence of bubonic plague in sylvatic reservoirs throughout the world, the causative agent (yersinia pestis) evolved in its present form within the last 20,000 years from enteropathogenic yersinia pseudotuberculosis. comparison of the genomes from the two species revealed that y. pestis possesses only a few unique plasmid-encoded genes that contribute to acute disease, whereas this organism has lost about 13% of the chromosomal genes that remain active in y. pseudotubercu ...201020158336
the omptins of yersinia pestis and salmonella enterica cleave the reactive center loop of plasminogen activator inhibitor 1.plasminogen activator inhibitor 1 (pai-1) is a serine protease inhibitor (serpin) and a key molecule that regulates fibrinolysis by inactivating human plasminogen activators. here we show that two important human pathogens, the plague bacterium yersinia pestis and the enteropathogen salmonella enterica serovar typhimurium, inactivate pai-1 by cleaving the r346-m347 bait peptide bond in the reactive center loop. no cleavage of pai-1 was detected with yersinia pseudotuberculosis, an oral/fecal pat ...201020639337
population structure and evolution of pathogenicity of yersinia pseudotuberculosis.yersinia pseudotuberculosis is an enteric human pathogen but is widespread in the environment. pathogenicity is determined by a number of virulence factors, including the virulence plasmid pyv, the high-pathogenicity island (hpi), and the y. pseudotuberculosis-derived mitogen (ypm), a superantigen. the presence of the 3 virulence factors varies among y. pseudotuberculosis isolates. we developed a multilocus sequence typing (mlst) scheme to address the population structure of y. pseudotuberculosi ...201021131531
identification and characterisation of a novel adhesin ifp in yersinia pseudotuberculosis.abstract:201121527009
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