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expression and immunologic characterization of recombinant heat shock protein 58 of leptospira species: a major target antigen of the humoral immune response.a clone of leptospira interrogans serovar lai that was isolated by immunoscreening of a genomic lambda library with sera from convalescent patients with leptospirosis directed expression of a unique 62-kda protein in escherichia coli. when examined by sds-page, the protein comigrated with an immunodominant protein present in leptospiral cell lysate. determination of the nucleotide sequence of the 2.7-kb insert dna identified two genes homologous to the hsp58 and hsp10 of l. interrogans serovar c ...199910619602
three case studies involving leptospira interrogans serovar pomona infection in mixed farming units.three case studies involving leptospira interrogans serovar pomona outbreaks within mixed farming systems in south africa are described. on 2 farms, pigs constituted the main enterprise with cattle and sheep of secondary importance. on each of these 2 farms, abortion due to l. pomona in sows was confirmed by culture, and antibody titres to pomona were detected in cattle, sheep, horses and dogs. on the 3rd farm, a piggery was of secondary importance to cattle farming. abortion and death in cows o ...199910855820
leptospirosis in portugal: epidemiology from 1991 to 1997.the term leptospirosis describes a group of diseases caused by members of the order spirochaetales, mainly the species leptospira interrogans. infection can be asymptomatic but disease of differing severity and clinical features (often suggestive of menin199912631907
[a molecular epidemiological investigation on leptospira interrogans serovar hebdomadis and australia in china].in order to confirm whether cattle serve the source of infection for patients with leptospira interrogans serovar hebdomadis and australia.200011860762
recombinant chimeric borrelia proteins for diagnosis of lyme disease.current serologic lyme disease tests use whole borrelia cells as the source of antigen. these assays are difficult to standardize and to optimize for sensitivity and specificity. to help solve these problems, we constructed a library of recombinant chimeric proteins composed of portions of key antigens of borrelia burgdorferi. these proteins were then used to develop an enzyme-linked immunosorbent assay. we compared our assay with the most sensitive of three whole-cell borrelia assays. we found ...200010878038
detection of leptospira spp. in the aqueous humor of horses with naturally acquired recurrent uveitis.leptospiral organisms have long been presumed to be associated with the presence of equine recurrent uveitis. this project was undertaken to determine the presence of leptospira spp. in the aqueous humor of horses with uveitis to determine if there was an association with inflammation. thirty horses were determined to have recurrent uveitis based on clinical evaluation or history. sixteen horses were judged clinically and historically to be free of uveitis and were used as controls. aqueous humo ...200010878072
spirochaetal lipoproteins and pathogenesis. 200010878114
evidence of cross-protection within leptospira interrogans in an experimental model.killed whole-cell preparations were used as bacterins against leptospirosis. as this type of protection is considered to be serogroup-specific, several serogroups were added to the usual vaccines, and the most pathogenic serovar was chosen for each group. different leptospire extracts were evaluated for their protective capacity against acute lethal leptospirosis in gerbils (meriones unguiculatus). total extracts induced complete protection against homologous challenges and partial protection ag ...200010924790
body distribution of poly-dl-lactide-poly(ethylene glycol) microspheres with entrapped leptospira interrogans antigens following intravenous and oral administration to guinea-pigs.poly-dl-lactide-poly(ethylene glycol) (pela) microspheres with entrapped antigens were administered intravenously and orally into guinea-pigs to quantitatively determine the in-vivo distribution and release profiles. pela microspheres containing 125i-labelled outer-membrane protein leptospira interrogans antigens (125i-omp) were prepared by double-emulsion solvent extraction procedure, and characterized with respect to size, morphology and in-vitro release profiles. the fractured sections of liv ...200010933126
uptake and killing of leptospira interrogans and borrelia burgdorferi, spirochetes pathogenic to humans, by reticuloendothelial cells in perfused rat liver.in situ-perfused rat livers were infused with a single dose of 1.5 x 10(7) radiolabeled cells of leptospira interrogans serovar icterohaemorrhagiae, the agent of leptospirosis, or with borrelia burgdorferi irs, the agent of lyme disease. significant (p<0.0001) differences in the liver uptake of l. interrogans and of b. burgdorferi were observed, the uptakes being 37.4%+/-2.3% for l. interrogans and 60.5%+/-3.1% for b. burgdorferi. leptospires, in contrast to borreliae, were recovered from the li ...200010948172
identification and partial characterization of a novel hemolysin from leptospira interrogans serovar lai.it has been suggested that leptospiral hemolysins are important in the virulence and pathogenesis of leptospirosis. we have isolated an escherichia coli clone carrying the 7.8kb dna insert from a genomic library of leptospira interrogans serovar lai by plaque hybridization using a sequence derived from the sphingomyelinase c gene (spha) of l. borgpetersenii. the clone showed a clear beta-hemolytic zone on sheep blood agar and high hemolytic activities on both human and sheep erythrocytes in liqu ...200010974532
serological prevalence to six leptospiral serovars in cattle in asturias (northern spain).the prevalence of antibody to six serovars of leptospira interrogans in cattle in asturias (northern spain) was determined by the microscopic agglutination test (mat). using 50% agglutination or lysis at a dilution of 1:10 or more as the criteria for seropositivity, 371 of 3578 (10.36%) animals were found to react with one serovar. the most commonly detected serovars were pomona (5.59%) and grippotyphosa (2.37%), whilst serovar hardjo (0.75%), icterohaemorrhagiae (0.64%), poi (0.64%) and autumna ...200010982084
leptospira autumnalis isolated from a human case from avadi, india, and the serovar's predominance in local rat and bandicoot populations.leptospira were successfully isolated from the urine of an indian patient who had been clinically diagnosed as having leptospirosis. in an attempt to determine the source of this infection, 28 rats (rattus rattus) and 58 bandicoots (bandicota bengalensis) living in the vicinity of the patient's home in avadi, a suburban area of the city of chennai (madras), india, were then investigated. each animal was checked for infection by microscopical examination of fresh and stained urine, serological an ...200010983563
borrelia burgdorferi periplasmic flagella have both skeletal and motility functions.bacterial shape usually is dictated by the peptidoglycan layer of the cell wall. in this paper, we show that the morphology of the lyme disease spirochete borrelia burgdorferi is the result of a complex interaction between the cell cylinder and the internal periplasmic flagella. b. burgdorferi has a bundle of 7-11 helically shaped periplasmic flagella attached at each end of the cell cylinder and has a flat-wave cell morphology. backward moving, propagating waves enable these bacteria to swim in ...200010995478
the le1 bacteriophage replicates as a plasmid within leptospira biflexa: construction of an l. biflexa-escherichia coli shuttle vector.we have discovered that le1, one of the plaque-forming phages previously described as lytic for the leptospira biflexa saprophytic spirochete (i. saint girons, d. margarita, p. amouriaux, and g. baranton, res. microbiol. 141:1131-1138, 1990), was indeed temperate. le1 was found to be unusual, as southern blot analysis indicated that it is one of the few phages to replicate in the prophage state as a circular plasmid. the unavailability of such small endogenous replicons has hindered genetic expe ...200011004167
polymerase chain reaction for the laboratory diagnosis of aseptic meningitis and encephalitis.a protocol for testing cerebrospinal fluid specimens using a range of pcr assays for the diagnosis of central nervous system infection was developed and used to test prospectively 383 specimens. pcr assays were used for the detection of adenovirus, borrelia burgdorferi, enteroviruses, epstein barr virus, cytomegalovirus, herpes simplex virus, human herpes virus type 6, jc virus, leptospira interrogans, listeria monocytogenes, lymphocytic choriomeningitis virus, measles virus, mumps virus, mycoba ...200011018820
localization of the leptospira interrogans metf gene on the cii secondary chromosome.an open reading frame of 885 nucleotides was identified as the leptospira interrogans metf gene. the deduced amino acid sequence (294 amino acids) showed similarities with escherichia coli methylene tetrahydrofolate reductase (metf or mthfr) (33% identity) and with the n-terminal part of human mthfr (33% identity). the l. interrogans metf gene complements an e. coli metf mutant to prototrophy, suggesting the functionality of the folate branch converging to form methionine. in addition, the l. in ...200011024273
hemolytic and hemoxidative activities in mycoplasma penetrans.mycoplasma penetrans is a newly isolated mollicute from the urine of patients infected with human immunodeficiency virus that demonstrates the capacity to adhere to and invade human cells. a previous report, based on assays with mouse red blood cells (rbcs), indicated that m. penetrans lacked hemolytic activity. in our studies, we incubated different isolates of m. penetrans with various rbc species and observed hemolytic zones surrounding individual mycoplasma colonies. all m. penetrans strains ...200011035754
the spirochete flaa periplasmic flagellar sheath protein impacts flagellar helicity.spirochete periplasmic flagella (pfs), including those from brachyspira (serpulina), spirochaeta, treponema, and leptospira spp., have a unique structure. in most spirochete species, the periplasmic flagellar filaments consist of a core of at least three proteins (flab1, flab2, and flab3) and a sheath protein (flaa). each of these proteins is encoded by a separate gene. using brachyspira hyodysenteriae as a model system for analyzing pf function by allelic exchange mutagenesis, we analyzed purif ...200011073915
cloning, sequencing, and transcriptional analysis of the dnak heat shock operon of listeria monocytogenes.the complete dnak operon of listeria monocytogenes was isolated by chromosome walking using the previously cloned dnak gene as a probe. molecular analysis of the locus identified 6 genes in the order hrca, grpe, dnak, dnaj, orf35, and orf29. primer extension analysis revealed 3 transcription start sites-s1, s2, and s3-upstream of the hrca, grpe, and dnaj, respectively. the transcription from s1 was heat inducible. analysis of the sequences revealed the consensus promoter sequences of gram-positi ...200010701836
microbial relatives of the seed storage proteins of higher plants: conservation of structure and diversification of function during evolution of the cupin superfamily.this review summarizes the recent discovery of the cupin superfamily (from the latin term "cupa," a small barrel) of functionally diverse proteins that initially were limited to several higher plant proteins such as seed storage proteins, germin (an oxalate oxidase), germin-like proteins, and auxin-binding protein. knowledge of the three-dimensional structure of two vicilins, seed proteins with a characteristic beta-barrel core, led to the identification of a small number of conserved residues a ...200010704478
[report on a leptospirosis outbreak in the city of santa fe, argentina, march-april 1998].in march-april 1998 in a neighborhood in the city of santa fe, argentina, there was an outbreak of an acute disease characterized by fever, headaches, and intense myalgias. this article presents the studies surrounding this outbreak and the attempts to identify the source and the mode of transmission. the epidemiological, serological, and clinical findings indicated that the causative agent was leptospira interrogans. as a screening test, macroscopic agglutination with heat-resistant antigen was ...200010715972
the leptospiral major outer membrane protein lipl32 is a lipoprotein expressed during mammalian infection.we report the cloning of the gene encoding the 32-kda lipoprotein, designated lipl32, the most prominent protein in the leptospiral protein profile. we obtained the n-terminal amino acid sequence of a staphylococcal v8 proteolytic-digest fragment to design an oligonucleotide probe. a lambda-zap ii library containing ecori fragments of leptospira kirschneri dna was screened, and a 5.0-kb dna fragment which contained the entire structural lipl32 gene was identified. several lines of evidence indic ...200010722630
identification of a 36-kda fibronectin-binding protein expressed by a virulent variant of leptospira interrogans serovar icterohaemorrhagiae.we investigated the ability of a virulent strain of leptospira interrogans serovar icterohaemorrhagiae, its isogenic avirulent variant and a saprophytic strain to bind fibronectin using alkaline phosphatase-labelled fibronectin. a single 36-kda fibronectin-binding protein was expressed only by the virulent strain and was located in the outer sheath according to proteinase k treatment results. the interaction of this protein with fibronectin was specific and the region of fibronectin bound to thi ...200010731601
antibody isotypes in sera of equine fetuses aborted due to leptospira interrogans serovar pomona-type kennewicki infection.leptospira-specific antibody isotypes in sera of late term equine fetuses aborted due to leptospira interrogans serovar pomona-type kennewicki infection were characterized and compared with those of their dams. igm was the dominant leptospira-specific isotype in both fetuses and mares. however, igga was the isotype in highest concentration in petal sera and strong leptospira-specific igga but no iggb and little or no igg(t) were detected. in contrast, although iggb was quantitatively the dominan ...200011137127
analysis of leptospira isolates from mainland portugal and the azores islands.from 228 recent leptospira isolates from mainland portugal and azorean wild mammals, 149 were characterized at the serovar level by monoclonal antibodies (mabs), a quick serological method in epidemiological studies. in order to compare this antigenic information with that from new genetic techniques, a sample of isolates was analyzed through pulsed-field agarose gel electrophoresis (pfge) (n=71), mapped restriction site polymorphisms (mrsps) in pcr-amplified rrna genes (n=45, including 13 sapro ...200010754245
genome plasticity among related ++lactococcus strains: identification of genetic events associated with macrorestriction polymorphisms.the genomic diversity of nine strains of the lactococcus lactis subsp. cremoris (ncdo712, ncdo505, ncdo2031, ncdo763, mms36, c2, lm0230, lm2301, and mg1363) was studied by macrorestriction enzyme analysis using pulsed-field gel electrophoresis. these strains were considered adequate for the investigation of genomic plasticity because they have been described as belonging to the same genetic lineage. comparison of apai and smai genome fingerprints of each strain revealed the presence of several m ...200010762249
detection and differentiation of leptospira spp. serovars in bovine semen by polymerase chain reaction and restriction fragment length polymorphism.in view of the importance of venereal transmission of bovine leptospirosis, the objective of the present study was to apply the polymerase chain reaction (pcr) to 26 serovars of leptospira interrogans, l. borgpetersenii, l. santarosai, l. noguchii and l. biflexa, to determine the detection threshold in semen samples and to evaluate the possibility of differentiation among serovars using 19 restriction endonucleases. the results showed that all serovars were amplified and the detection threshold ...200010781725
serosurvey for selected infectious disease agents in free-ranging black and white rhinoceros in africa.two hundred and eighty one serum samples collected from free-ranging black (diceros bicornis) and white (ceratotherium simum) rhinoceros, in the republic of south africa (rsa), namibia, and kenya from 1987-97, were examined for antibody to 16 different infectious agents. positive antibody titers were detected against akabane (59.8%), bluetongue (55%), african horse sickness (27.9%), epizootic haemorrhagic disease of deer (19.4%), parainfluenza type 3 (25.3%), bovine herpes virus 1 (3.1%), equine ...200010813614
cloning and characterization of the mammalian brain-specific, mg2+-dependent neutral sphingomyelinase.the enzymatic breakdown of sphingomyelin by sphingomyelinases is considered the major source of the second messenger ceramide. studies on the contribution of the various described acidic and neutral sphingomyelinases to the signaling pool of ceramide have been hampered by the lack of molecular data on the neutral sphingomyelinases (nsmases). we recently identified a mammalian nsmase, an integral membrane protein with remote similarity to bacterial sphingomyelinases. however, its ubiquitous expre ...200010823942
rpob gene analysis as a novel strategy for identification of spirochetes from the genera borrelia, treponema, and leptospira.spirochetes are emerging pathogens for which culture and identification are partly unresolved. in fact, 16s rrna-based sequencing is by far the most widely used pcr methodology that is able to detect such uncultivable pathogens. however, this assay actually has some limitations linked to potential problems of contamination, which hampers diagnosis. to circumvent this, we have devised a simple pcr strategy involving targeting of the gene encoding the rna polymerase beta subunit (rpob), a highly c ...200010834976
[leptospirosis after a staff outing].three male colleagues aged between 34 and 38 years were admitted at the same time to three different rhein-main area hospitals. they presented with a variety of symptoms, including high fever (39.0 to 40.0 degrees c), chills, headache with meningismus or facial paralysis, mild hepatitis and renal involvement. about 18 days before they had been together on a boat rafting tour when the boat capsized when they had fallen into a river in high flood.200011256045
leptospirosis in kuala lumpur and the comparative evaluation of two rapid commercial diagnostic kits against the mat test for the detection of antibodies to leptospira interrogans.the aim of the study was to look into the epidemiology of serodiagnosed cases of leptospirosis at the university hospital and compare two commercial elisa assays to the microscopic agglutination test (mat). demographic data for all serodiagnosed cases for the years 1991-1997 were collected. from this data, 104 sera (n = 104) were selected as samples for comparative evaluation of the commercial elisas (indx dip-s-ticks and panbio elisa) to the mat test. thirty two (n = 32) negative control sera w ...200011256343
evaluating genome dynamics: the constraints on rearrangements within bacterial genomes.inversions and translocations distinguish the genomes of closely related bacterial species, but most of these rearrangements preserve the relationship between the rearranged fragments and the axis of chromosome replication. within species, such rearrangements are found less frequently, except in the case of clinical isolates of human pathogens, where rearrangements are very frequent.200011380986
characterization of the leptospira interrogans s10-spc-alpha operon.a ribosomal protein gene cluster from the spirochaete leptospira interrogans was characterized. this locus is homologous to the escherichia coli s10, spc, and alpha operons. analysis of l. interrogans rna showed that the ribosomal protein genes within this cluster are co-transcribed, thus forming an operon. two transcription initiation sites were mapped by primer extension, upstream of fus, the first gene in this cluster, and sequences from this region provided promoter activity in e. coli. tran ...200010620683
potential role of phospholipases in virulence and fungal pathogenesis.microbial pathogens use a number of genetic strategies to invade the host and cause infection. these common themes are found throughout microbial systems. secretion of enzymes, such as phospholipase, has been proposed as one of these themes that are used by bacteria, parasites, and pathogenic fungi. the role of extracellular phospholipase as a potential virulence factor in pathogenic fungi, including candida albicans, cryptococcus neoformans, and aspergillus, has gained credence recently. in thi ...200010627494
functional conservation of the polysaccharide biosynthetic protein wbpm and its homologues in pseudomonas aeruginosa and other medically significant bacteria.wbpm is a highly conserved protein involved in synthesis of the o antigens of pseudomonas aeruginosa. homologues of this protein have been identified in a large number of bacteria, and they can be divided into two subfamilies: subfamily 1, including wbpm, contains large proteins ( approximately 600 amino acids), while subfamily 2, typified by hp0840 (flaa1) of helicobacter pylori, contains smaller proteins ( approximately 350 amino acids) homologous to the c termini of proteins in subfamily 1. a ...200010639466
monoclonal antibodies suitable for incorporation into a competitive enzyme-linked immunosorbent assay (elisa) for detection of specific antibodies to leptospira interrogans serovar pomona.monoclonal antibodies (mab) were produced by fusing sp2/0-ag14 myeloma cells with spleen cells from balb/c and nd4 mice that were immunized with killed leptospira interrogans serovar pomona whole cells. thirty hybridomas which produced antibodies (of the igg1, igg2a, igg2b, or igg3 isotype) that bound to epitopes on the serovar pomona whole cell antigen were identified by an indirect enzyme-linked immunosorbent assay (elisa). twenty-eight of these 30 mabs cross-reacted in the indirect elisa with ...200010665542
development of an indirect enzyme-linked immunosorbent assay for the detection of leptospiral antibodies in dogs.serology plays an important role in the diagnosis of leptospirosis. few laboratories have the resources, expertise, or facilities to perform the microscopic agglutination test (mat). thus, there is a need for a rapid and simple serological test that could be used in any diagnostic laboratory. in this study, a genus-specific, heat-stable antigenic preparation from leptospira interrogans serovar pomona was used in an enzyme-linked immunosorbent assay (elisa) for the detection of leptospiral antibo ...200010680654
a clonal subpopulation of leptospira interrogans sensu stricto is the major cause of leptospirosis outbreaks in brazil.leptospira is a highly diverse genus comprising many species and serogroups in brazil as well as all over the world. however, a study by arbitrarily primed pcr of 44 leptospiral strains isolated from humans during three different outbreaks in brazilian urban centers reveals that 43 of 44 isolates exhibit very similar fingerprints. analysis of these isolates indicates that they belong to a clonal subpopulation of leptospira interrogans sensu stricto.200010618140
leptospira infections in trappers from ontario.four trappers presented to the middlesex-london health unit in november, 1997 with similar clinical presentations. all four complained of fever, chills and headache, and three of the four had severe muscle aches. all gave histories of trapping raccoons before the onset of illness. three of the four men exhibited diagnostic seroconversions to leptospira grippotyphosa.200018159265
macrolide resistance conferred by base substitutions in 23s rrna. 200111120937
[integrated disease control in dairy herds. a case study from the veterinarians' viewpoint].integrated control of bovine virus diarrhoea virus, bovine herpesvirus-1, leptospira interrogans serovar hardjo subtype hardjobovis, mycobacterium avium subsp. paratuberculosis, and salmonella dublin in dairy herds may provide economic benefits superior to those obtained by sequential disease control, because, among other things, it allows optimization of voluntary culling. however, in practice there are no adequate instruments to establish priorities in voluntary culling. therefore, in this stu ...200111392987
listeria pathogenesis and molecular virulence determinants.the gram-positive bacterium listeria monocytogenes is the causative agent of listeriosis, a highly fatal opportunistic foodborne infection. pregnant women, neonates, the elderly, and debilitated or immunocompromised patients in general are predominantly affected, although the disease can also develop in normal individuals. clinical manifestations of invasive listeriosis are usually severe and include abortion, sepsis, and meningoencephalitis. listeriosis can also manifest as a febrile gastroente ...200111432815
leptospiral proteins recognized during the humoral immune response to leptospirosis in humans.leptospirosis is an emerging zoonosis caused by pathogenic spirochetes belonging to the genus leptospira. an understanding of leptospiral protein expression regulation is needed to develop new immunoprotective and serodiagnostic strategies. we used the humoral immune response during human leptospirosis as a reporter of protein antigens expressed during infection. qualitative and quantitative immunoblot analysis was performed using sera from 105 patients from brazil and barbados. sera from patien ...200111447174
genetic differences among the lps biosynthetic loci of serovars of leptospira interrogans and leptospira borgpetersenii.the gene organization in the lipopolysaccharide biosynthetic (rfb) locus was analyzed in seven leptospira interrogans serovars within serogroup icterohemorrhagiae, seven non-icterohemorrhagiae serovars and one leptospira borgpetersenii serovar. two groups of loci were delineated based on dna hybridization and sequence analysis. group 1 contained the two hardjo subtypes, hardjoprajitno and hardjobovis. group 2 (containing copenhageni, pomona, naam, mwogolo, smithi, lai, canicola, autumnalis, pyro ...200111476985
[leptospira interrogans serovar pomona: detection of antigenic differences among 3 regional isolates from cattle and a reference strain].leptospirosis is a zoonosis caused by leptospira interrogans. this disease is diagnosed by quantification of specific immunoglobulins in serum by the microagglutination test (mat). the aims of this research were: a) to compare the protein profiles of 3 clinical isolates of bovine leptospirosis with the reference strain used for the mat, and b) to identify the immunodomain antigens of the regional isolates through page and immunoblotting techniques of bovine sera from infected, vaccinated and mat ...200111494753
leptospira strains kept at the national centre for leptospirosis in rome, italy.since the national centre for leptospirosis (department of bacteriology and medical mycology, istituto superiore di sanità, rome) was established in 1956 by b. babudieri, efforts have been devoted to identifying new leptospira isolates and maintaining a collection of strains that today comprises 670 strains, 550 of which have been totally or partially classified, and 120 are still under study. this collection includes 23 serogroups and 156 serovars of pathogenic leptospires, and 32 serogroups an ...200111497082
borrelia burgdorferi reva antigen is a surface-exposed outer membrane protein whose expression is regulated in response to environmental temperature and ph.borrelia burgdorferi, the causative agent of lyme disease, produces reva protein during the early stages of mammalian infection. b. burgdorferi apparently uses temperature as a cue to its location, producing proteins required for infection of warm-blooded animals at temperatures corresponding to host body temperature, but does not produce such virulence factors at cooler, ambient temperatures. we have observed that b. burgdorferi regulates expression of reva in response to temperature, with the ...200111500397
evaluation of recombinant leptospira antigen-based enzyme-linked immunosorbent assays for the serodiagnosis of leptospirosis.there is an urgent need for development of new serodiagnostic strategies for leptospirosis, an emerging zoonosis with worldwide distribution. we have evaluated the diagnostic utility of five recombinant antigens in enzyme-linked immunosorbent assays (elisas) for serodiagnosis of leptospirosis. sera from 50 healthy residents of a high-incidence region were used to determine cutoff values for 96% specificity. in paired sera from 50 cases of leptospirosis confirmed by the microscopic agglutination ...200111526167
motility and chemotaxis in tissue penetration of oral epithelial cell layers by treponema denticola.the ability to penetrate tissue is an important virulence factor for pathogenic spirochetes. previous studies have recognized the role of motility in allowing pathogenic spirochetes to invade tissues and migrate to sites favorable for bacterial proliferation. however, the nature of the movements, whether they are random or controlled by chemotaxis systems, has yet to be established. in this study, we addressed the role of motility and chemotaxis in tissue penetration by the periodontal disease-a ...200111553571
serum and vitreous humor antibody titers in and isolation of leptospira interrogans from horses with recurrent uveitis.to measure antibody titers against leptospira interrogans in serum and vitreous humor and determine the prevalence of l interrogans in vitreous humor of horses with recurrent uveitis.200111561656
killing effect and antitoxic activity of the leptospira interrogans toxin-antitoxin system in escherichia coli.we report the first evidence of a chromosome-encoded toxin-antitoxin locus in spirochetes. this locus has been found in the pathogenic spirochete leptospira interrogans and exhibits homologies with the pem/chp loci. the l. interrogans chp locus consists of two genes: chpk (for "killer protein") and its upstream partner chpi (for "inhibitory protein"). expression of chpk in escherichia coli results in the inhibition of bacterial growth. the coexpression of chpi neutralizes chpk toxicity. by south ...200111591696
identification of the hemolysis-associated protein 1 as a cross-protective immunogen of leptospira interrogans by adenovirus-mediated vaccination.new vaccine strategies are needed for the prevention of leptospirosis, a widespread human and animal disease caused by pathogenic leptospires. our previous work determined that a protein leptospiral extract conferred cross-protection in a gerbil model of leptospirosis. the 31- to 34-kda protein fraction of leptospira interrogans serovar autumnalis was shown sufficient for this purpose. in the present study, n-terminal sequencing of a 32-kda fraction and southern blotting of genomic dna with corr ...200111598056
immunoperoxidase and histopathological examinations of leptospiral nephritis in cattle.this study was designed to investigate the role of leptospirae in interstitial nephritis. sixty-eight white-spotted kidneys and 30 grossly normal kidneys from slaughtered cattle were examined histologically and immunohistochemically for the presence of leptospira interrogans antigens. the presence of l. interrogans antigens was found in 21 of 68 white-spotted kidneys and in four of 30 normal kidneys. in conclusion, the detected incidence of infection with l. interrogans was not high, but there w ...200111599681
role of the coypu (myocastor coypus) in the epidemiology of leptospirosis in domestic animals and humans in france.the coypu (myocastor coypus), a rodent whose natural habitat is stagnant freshwater, has become a widespread pest in france within the last decade. this study investigated the prevalence of seropositivity and the renal carriage of leptospires in coypus in order to evaluate their role in terms of the risk of infection by leptospira interrogans in domestic animals and humans. the study involved the application of serological and bacteriological methods to identify leptospires infection and/or carr ...200111599683
evaluation of two enzyme-linked immunosorbent assays for detecting salmonella enterica subsp. enterica serovar dublin antibodies in bulk milk.two enzyme-linked immunosorbent assays (elisas) for the detecting salmonella enterica subsp. enterica serovar dublin antibodies in bulk milk were developed and evaluated for potential use in control programs. the elisas were based on either lipopolysacharide (lps elisa) or flagellar antigen (gp elisa). sensitivity was determined with 79 case herds with a wide range of clinical signs. specificity was determined with 125 dutch and 200 swedish control herds. the relation between antibodies in bulk ...200111687438
borrelia burgdorferi antibodies in dogs from cotia county, são paulo state, brazil.dogs sera samples collected from cotia county, são paulo were tested using indirect immunoenzymatic test (elisa) in order to study lyme disease serology in dogs. elisa method was standardized and g39/40 north american strain of borrelia burgdorferi was used as antigen. positive results were confirmed employing the western blotting technique. because of the possibility of cross-reactions, sera were also tested for different serological strains of leptospira interrogans and l. biflexa using micros ...200111696846
protective killed leptospira borgpetersenii vaccine induces potent th1 immunity comprising responses by cd4 and gammadelta t lymphocytes.leptospira borgpetersenii serovar hardjo is the most common cause of bovine leptospirosis and also causes zoonotic infections of humans. a protective killed vaccine against serovar hardjo was shown to induce strong antigen-specific proliferative responses by peripheral blood mononuclear cells (pbmc) from vaccinated cattle by 2 months after the first dose of vaccine. this response was absent from nonvaccinated control cattle. the mean response peaked by 2 months after completion of the two-dose v ...200111705932
molecular characterization of thermoinduced immunogenic proteins q1p42 and hsp15 of leptospira interrogans.leptospira interrogans is a mammalian pathogen which must adapt to a range of new environmental conditions including temperature change when it infects new hosts. in vitro studies of organisms cultured at 30 degrees c and shifted to 37 degrees c for 5 to 7 days have confirmed that synthesis of several proteins involved in equine infection is regulated in response to temperature change (j. e. nally, j. f. timoney, and b. stevenson, infect. immun. 69:400-404, 2001). in order to specifically identi ...200111705941
[notification according to the law for protection against infections].since january 1st 2001, the law for protection against infections decrees the duty of notification along two tracks, on the one hand by notification of infectious diseases and on the other hand by reporting the pathogens. however, the names of pathogens change due to scientific progress. furthermore, these names include in some cases not only harmful agents of infectious diseases but also inoffensive organisms, i. e. giardia lamblia. there are also problems in the notification of other pathogens ...200111735068
leptospiral lipopolysaccharide activates cells through a tlr2-dependent mechanism.leptospira interrogans are zoonotic pathogens that have been linked to a recent increased incidence of morbidity and mortality in highly populated tropical urban centers. they are unique among invasive spirochetes in that they contain outer membrane lipopolysaccharide (lps) as well as lipoproteins. here we show that both these leptospiral outer membrane constituents activate macrophages through cd14 and the toll-like receptor 2 (tlr2). conversely, it seems that tlr4, a central component for reco ...200111276206
leptospirosis.leptospirosis is a worldwide zoonotic infection with a much greater incidence in tropical regions and has now been identified as one of the emerging infectious diseases. the epidemiology of leptospirosis has been modified by changes in animal husbandry, climate, and human behavior. resurgent interest in leptospirosis has resulted from large outbreaks that have received significant publicity. the development of simpler, rapid assays for diagnosis has been based largely on the recognition that ear ...200111292640
first evidence for gene replacement in leptospira spp. inactivation of l. biflexa flab results in non-motile mutants deficient in endoflagella.leptospira spp. offer many advantages as model bacteria for the study of spirochaetes. however, homologous recombination between introduced dna and the corresponding chromosomal loci has never been demonstrated. a unique feature of spirochaetes is the presence of endoflagella between the outer membrane sheath and the cell cylinder. we chose the flab flagellin gene, constituting the flagellar core, as a target for gene inactivation in the saprophyte leptospira biflexa. the amino acid sequence of ...200111298286
morbidity-mortality factors and survival of an urban coyote population in arizona.the health of coyotes (canis latrans) in urban areas has not been studied. our objectives were to assess the health of coyotes in tucson (arizona, usa) by determining the prevalence of antibodies to selected pathogens, estimating survival rates, and identifying sources of mortality. we drew blood from 22 coyotes to evaluate the prevalence of heartworm (dirofilaria immitis) antigens, and antibodies to canine distemper virus (cdv), infectious canine hepatitis (ich), canine parvovirus (cpv), and se ...200111310882
brachyspira (serpulina) hyodysenteriae gyrb mutants and interstrain transfer of coumermycin a(1) resistance.to further develop genetic techniques for the enteropathogen brachyspira hyodysenteriae, the gyrb gene of this spirochete was isolated from a lambdazapii library of strain b204 genomic dna and sequenced. the putative protein encoded by this gene exhibited up to 55% amino acid sequence identity with gyrb proteins of various bacterial species, including other spirochetes. b. hyodysenteriae coumermycin a(1)-resistant (cn(r)) mutant strains, both spontaneous and uv induced, were isolated by plating ...200111319078
new tests for syphilis: rational design of a pcr method for detection of treponema pallidum in clinical specimens using unique regions of the dna polymerase i gene.a sensitive and specific pcr method to detect treponema pallidum in clinical specimens was developed. pcr primers were designed based on two unique features of the dna polymerase i gene (pola). the first distinctive characteristic is that the region codes for a high cysteine content and has low homology with similar regions of dna polymerase i gene from known microorganisms. the second unique feature is the presence of four insertions in the gene. pcr tests using primers designed on the basis th ...200111326018
serological study of the frequency of leptospiral infections among dairy cows in farms with suboptimal reproductive efficiency in galicia, spain.between march 1996 and september 1997, 15 farms located in galicia (nw spain) and experiencing suboptimal reproductive efficiency were visited and blood samples were obtained from all the lactating cows (n=442). additionally, 1060 samples were obtained monthly from a cohort of 219 lactating cows belonging to nine of the farms between march 1996 and april 1997. all the samples were tested by microscopic agglutination (mat) using live antigens representing the following leptospira interrogans sero ...200111337143
lipid metabolic changes in experimentally induced leptospiral infection with serovars australis, canicola and icterohaemorrhagiae.changes in lipid fractions were evaluated in young guinea pigs when infected with 1 ml of 7 day old live cultures of leptospira interrogans serovars australis, canicola and icterohaemorrhagiae. statistically significant elevation in triglycerides, very low density lipoprotein and phospholipid and a significant reduction in high density lipoprotein (hdl) in all the groups was observed. cholesterol and low density lipoprotein showed ascending trend in icterohaemorrhagiae group, whereas they were n ...200111349531
[a case of leptospirosis infected in borneo island, malaysia].we report a case of leptospirosis infected in sabah, borneo island, malaysia. the case is 25-year-old male who had participated in the ecochallenge sabah 2000 expedition race, a multisport event held during august 20 to september 3, 2000 at various sites in sabah in malaysian borneo. he developed a high fever and headache on september 7, and he was admitted to our hospital on september 9. on admission he also had conjunctivitis and myalgias. laboratory findings on admission revealed leukocytosis ...200111806141
competitive enzyme-linked immunosorbent assay for detection of leptospira interrogans serovar pomona antibodies in bovine sera.a competitive enzyme-linked immunosorbent assay (elisa) using a specific monoclonal antibody (m898) was developed for detection of bovine antibodies to leptospira interrogans serovar pomona. this assay was evaluated using field sera (n = 190) with serovar pomona microscopic agglutination test (mat) titers of > or =100 as the positive population (group a); field sera (n = 1,445) which were negative in the mat (1:100 dilution) for serovar pomona (group b); and sera (from a specific-pathogen-free c ...200111139193
lateral-flow assay for rapid serodiagnosis of human leptospirosis.an assay device for the rapid detection of leptospira-specific immunoglobulin m (igm) antibodies in human sera is presented. the sensitivity (85.8%) and specificity (93.6%) of the assay compared well (91.9% agreement) with those of an igm enzyme-linked immunosorbent assay routinely used in the serodiagnosis of leptospirosis. the sensitivity of the assay varied with the stage of the disease. the assay uses stabilized components and is simply performed by the addition of serum and sample fluid to ...200111139212
use of rpob gene analysis for detection and identification of bartonella species.identification of bartonella species is of increasing importance as the number of infections in which these bacteria are involved increases. to date, these gram-negative bacilli have been identified by various serological, biochemical, and genotypic methods. however, the development of alternative tools is required, principally to circumvent a major risk of contamination during sample manipulation. the aim of our study was to investigate the possible identification of various bartonella species ...200111158086
effects of hydrostatic pressure on the leptospira interrogans: high immunogenicity of the pressure-inactivated serovar hardjo.the hardjoprajitno strain of leptospira interrogans serovar hardjo was subjected to different hydrostatic pressures. complete inactivation occurred when the leptospires were treated with 2 kbar for 60 min. electron microscopy showed dislocation of the outer membrane, partial loss of the helical shape and extrusion of the axial filament from the cytoplasmic cylinder of the pressurized leptospires. when the pressure-treated leptospires were inoculated into rabbits they were highly immunogenic. the ...200111163675
polarized entry of uropathogenic afa/dr diffusely adhering escherichia coli strain ih11128 into human epithelial cells: evidence for alpha5beta1 integrin recognition and subsequent internalization through a pathway involving caveolae and dynamic unstable microtubules.afa/dr diffusely adhering escherichia coli strain ih11128 bacteria basolaterally entered polarized epithelial cells by a cd55- and cd66e-independent mechanism through interaction with the alpha5beta1 integrin and a pathway involving caveolae and dynamic microtubules (mts). ih11128 invasion within hela cells was dramatically decreased after the cells were treated with the cholesterol-extracting drug methyl-beta-cyclodextrin or the caveola-disrupting drug filipin. disassembly of the dynamically un ...200111179364
penicillin-binding proteins in leptospira interrogans.the leptospira interrogans pona and pbpb genes were isolated and characterized. pona and pbpb encode the penicillin-binding proteins (pbps) 1 and 3, respectively. there is little sequence variation between the pbp genes from two l. interrogans strains (serovar icterohaemorrhagiae strain verdun and serovar pomona strain rz11). the deduced l. interrogans pbp 1 and pbp 3 protein sequences from the two strains shared over 50% similarity to homologous proteins from escherichia coli. it was demonstrat ...200111181373
dogs as sentinels for human lyme borreliosis in the netherlands.serum samples from hunters (n = 440), their hunting dogs (n = 448), and hunters without dog ownership (n = 53) were collected in the netherlands at hunting dog trials and were tested for antibodies against borrelia burgdorferi by a whole-cell enzyme-linked immunosorbent assay. additionally, 75 healthy pet dogs were tested. the results of this study indicate that the seroprevalence among hunting dogs (18%) was of the same order as the seroprevalence among pet dogs (17%) and hunters (15%). the ser ...200111230393
identification of residues involved in catalytic activity of the inverting glycosyl transferase wbbe from salmonella enterica serovar borreze.synthesis of the o:54 o antigen of salmonella enterica is initiated by the nonprocessive glycosyl transferase wbbe, assigned to family 2 of the glycosyl transferase enzymes (gt2). gt2 enzymes possess a characteristic n-terminal domain, domain a. based on structural data from the gt2 representative spsa (s. j. charnock and g. j. davies, biochemistry 38:6380-6385, 1999), this domain is responsible for nucleotide binding. it possesses two invariant asp residues, the first forming a hydrogen bond to ...200111114903
temperature-regulated protein synthesis by leptospira interrogans.leptospira interrogans is an important mammalian pathogen. transmission from an environmental source requires adaptations to a range of new environmental conditions in the organs and tissues of the infected host. since many pathogenic bacteria utilize temperature to discern their environment and regulate the synthesis of appropriate proteins, we investigated the effects of temperature on protein synthesis in l. interrogans. bacteria were grown for several days after culture temperatures were shi ...200111119530
identification of new repetitive element in leptospira interrogans serovar copenhageni and its application to pcr-based differentiation of leptospira serogroups.a new repetitive dna element was identified in an isolate of leptospira interrogans serovar copenhageni from a patient in salvador, brazil. a sau3a genomic library from this strain was constructed and screened for repetitive dna elements. an insert of 438 bp (rep1) from one library clone hybridized to multiple chromosomal dna fragments resolved electrophoretically after digestion with bamhi, hindiii, and mfei. a single oligonucleotide primer, designated irepl, was designed to generate multiple p ...200111136769
[detection of leptospirosis reservoirs in madagascar using the polymerase chain reaction technique].a polymerase chain reaction (pcr) technique was used for detection of the leptospira interrogans rrs gene in kidney tissue from 115 rats, 50 zebu cattles and 13 pigs in an attempt to identify a possible animal reservoir of leptospirosis in madagascar. in addition, serological testing of 105 individuals in close contact with animals was carried out. the pcr analysis was negative for all the samples tested and only one person was found seropositive at a low titer. the findings suggest that leptosp ...200112471745
rattus norvegicus acting as reservoir of leptospira interrogans in the middle black sea region of turkey, as evidenced by pcr and presence of serum antibodies to leptospira strain.leptospirosis, a common form of zoonosis, especially in rainy countries, is caused by leptospira interrogans. in our region of turkey this type of disease has often been encountered in connection with rice harvesting and we therefore attempted to evaluate the prevalence of l. interrogans in wild rats in our region. fifty-nine rattus norvegicus rats were trapped alive in different areas of an approximately 100 km stretch of seashore in the middle black sea region of turkey. l. interrogans was det ...200111868761
seroprevalence of bovine leptospirosis in garanhuns municipal district, pernambuco state, brazil.the prevalence of leptospira interrogans serovars in dairy cattle was determined by analyzing 464 serum samples from cows on 15 properties in garanhuns municipal district, pernambuco state, brazil. a microscopic seroagglutination test including 12 serovars of leptospira interrogans as antigens was used. samples with titres 100 were considered positive. two hundred and twenty-one (47.63%) of the samples were positive to one or more serovars. the prevalence of the serovars was hardjo (21.98%), bra ...200112026062
infectious disease serologic survey in free-ranging venezuelan anacondas (eunectes murinus).reptiles can harbor pathogenic microorganisms asymptomatically and serve as potential reservoirs of infection for humans, domestic animals, and other reptiles. infectious diseases are also problematic for free-ranging reptile populations and are an important consideration in reptile reintroduction and translocation projects. there have been limited serologic studies of free-ranging reptiles for evidence of exposure to potential pathogens. in the present study, serum or plasma samples from five m ...200112785679
identification of leptospiral isolates by bacterial restriction endonuclease analysis (brenda).dna samples from 19 reference serovars belonging to 19 different serogroups of leptospira interrogans and two serovars belonging to leptospira biflexa were examined by bacterial restriction endonuclease analysis using ecor i and hae iii enzymes. all the serovars gave unique restriction patterns that differed from each other. dna from 10 local isolates digested with these enzymes produced patterns which on comparison with the standard patterns produced by reference strains could be identified to ...200117664802
[construction of dna vaccine including a chimeric gene encoding flagellin and outer membrane protein antigen from leptospira interrogons serovar lai].to construct a fusion expression vector for dna vaccine, including a flagellin gene (flab2) and an outer membrane protein gene (ompl1) to enhance the protective immunity of leptospira interrogans serova lai (stain 017).200212575175
[growth, virulence and antigenecity of leptospira interrogans serovar mozdok in modified emjh medium].the effect of higher tween 80 concentrations in emjh synthetic medium on the growth, virulence and antigenecity of leptospira interrogans serovar mozdok was evaluated for increasing the performances and making a full use of the detoxifying capacity of bovine serum albumin. the growth was spectrophotographically evaluated by the analysis of the bacterial growth kinetics; the obtained biomass performance and the consumption of the carbon source. the virulence was estimated in syrian hamster model ...200215846938
an improved immunohistochemical diagnostic technique for canine leptospirosis using antileptospiral antibodies on renal tissue.the purpose of this study was to compare the immunoreactivity in canine renal tissues stained with antisera specific for 3 leptospiral antigens and those processed with traditional staining methods. in addition, immunoglobulin staining was done on tissues with immunoreactivity to leptospiral antigens. formalin-fixed renal sections from 12 dogs with chronic interstitial nephritis suspected or proven to have leptospirosis (6 dogs with silver-stained leptospires and 6 dogs in which silver-stained l ...200212680639
the construction and expression of recombinant shuttle plasmid with ompl1 gene from leptospira interrogans serovar lai strain 017 in bacille calmette-guerin.to construct recombinant bcg against leptospirosis.200212906159
a multiplex pcr for the detection of brucella spp. and leptospira spp. dna from aborted bovine fetuses.bovine brucellosis and leptospirosis are important causes of bovine abortion around the world. both diseases can be serologically diagnosed, but many factors may cause false positive and negative results. direct methods based on bacteriological isolation are usually employed, but they are difficult, time consuming and dangerous. monoplex polymerase chain reaction (pcr) have been successfully described for the detection of brucella spp. and leptospira spp. aiming at improvement in the direct diag ...200212034542
lipopolysaccharide endotoxins.bacterial lipopolysaccharides (lps) typically consist of a hydrophobic domain known as lipid a (or endotoxin), a nonrepeating "core" oligosaccharide, and a distal polysaccharide (or o-antigen). recent genomic data have facilitated study of lps assembly in diverse gram-negative bacteria, many of which are human or plant pathogens, and have established the importance of lateral gene transfer in generating structural diversity of o-antigens. many enzymes of lipid a biosynthesis like lpxc have been ...200212045108
lipopolysaccharide endotoxins.bacterial lipopolysaccharides (lps) typically consist of a hydrophobic domain known as lipid a (or endotoxin), a nonrepeating "core" oligosaccharide, and a distal polysaccharide (or o-antigen). recent genomic data have facilitated study of lps assembly in diverse gram-negative bacteria, many of which are human or plant pathogens, and have established the importance of lateral gene transfer in generating structural diversity of o-antigens. many enzymes of lipid a biosynthesis like lpxc have been ...200212045108
probability of and risk factors for introduction of infectious diseases into dutch spf dairy farms: a cohort study.a 2-year cohort study was conducted to investigate the probability of disease introduction into dutch dairy farms. the farms were tested regularly for diseases and were visited biannually to collect management data. ninety-five specific pathogen-free (spf) dairy farms were selected from a database of bovine herpesvirus type 1 (bhv1)-free farms to study the probability of, and risk factors for, introduction of bhv1, bovine viral diarrhoea virus (bvdv), salmonella enterica subsp. enterica serotype ...200212114014
enzymatic properties of a new peptide deformylase from pathogenic bacterium leptospira interrogans.peptide deformylase (lipdf), a target protein for antibacterial agents from pathogenic bacteria leptospira interrogans was identified and purified. enzymatic studies including kinetics and inhibition revealed new inspiring highlights. the purified active enzyme was a dimer and showed a hyperbolic progress plot when the substrate was low but an excess substrate inhibition effect in higher substrate concentration. variants on the metal-binding ligand-cys102 were constructed to verify the indispens ...200212127977
occupational health and safety in small animal veterinary practice: part i--nonparasitic zoonotic diseases.zoonotic diseases are an ever-present concern in small animal veterinary practice and are often overlooked. a variety of nonparasitic zoonotic diseases may be encountered in small animal practice, including cat scratch disease (bartonellosis), cat bite abscesses, rabies, leptospirosis, methicillin-resistant staphylococcus aureus, clostridium difficile-associated diarrhea, salmonellosis, avian chlamydiosis, campylobacteriosis, dermatophytosis, and blastomycosis. these may cause human disease rang ...200212170843
lethal leptospiral pulmonary hemorrhage: an emerging disease in buenos aires, argentina. 200212194784
molecular typing of papillomatous digital dermatitis-associated treponema isolates based on analysis of 16s-23s ribosomal dna intergenic spacer regions.papillomatous digital dermatitis (pdd), an emerging infectious disease of cattle, is characterized by painful, ulcerative foot lesions. the detection of high numbers of invasive spirochetes in pdd lesions suggests an important role for these organisms in the pathogenesis of pdd. pdd-associated spirochetes have phenotypic characteristics consistent with members of the genus treponema: partial 16s ribosomal dna (rdna) sequence analysis of clonal isolates from california cattle showed that they com ...200212202594
evaluation of a novel commercial enzyme-linked immunosorbent assay detecting coxiella burnetii-specific immunoglobulin g for q fever prevaccination screening and diagnosis.a novel commercially available enzyme-linked immunosorbent assay (elisa) for prevaccination screening and diagnosis of q fever (panbio coxiella burnetii immunoglobulin g [igg] elisa) was compared to the complement fixation test (cft), and the indirect fluorescent-antibody test (ifat) was used to resolve discrepant results between the other two tests. a total of 214 serum samples was tested. the elisa demonstrated a specificity of 96% (46 of 48 samples) and a sensitivity of 71% (95 of 134 samples ...200212202611
isolation of salmonella enterica and serologic reactivity to leptospira interrogans in opossums (didelphis virginiana) from yucatán, méxico.the presence of salmonella enterica and serologic evidence of infection by leptospira interrogans, were detected in the opossum didelphis virginiana in a semi-urban locality of the yucatán state, méxico. ninety-one opossums were captured during the period april 1996 and may 1998. from a total of 17 feces samples, four salmonella enterica subsp. enterica serotypes (sandiego, newport, anatum, and minnesota), and one salmonella enterica subsp. arizonae serovar o44:z4,z23:- were isolated. some oposs ...200212219118
serological survey of leptospirosis in sows with premature birth and stillbirth in chiba and gunma prefectures of japan.in 1996 and 1997, the seroprevalence against leptospira in parturient sows with premature birth or stillbirth from two herds was investigated. in three out of four sow serum samples obtained in gunma prefecture, the antibody titers to leptospira interrogans serovar copenhageni (m20) were higher than 10,000 (the reciprocal of the serum dilution). furthermore, the antibody titers to l. interrogans serovar canicola (hond utrecht iv) were significantly high in the three sows and the titers ranged fr ...200212237523
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