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characterization and taxonomic significance of lipopolysaccharides of leptospira interrogans serovar hardjo.lipopolysaccharides (lpss) from leptospira interrogans serovar hardjo (reference strain hardjoprajitno and strain hardjobovis) were prepared by the hot phenol-water procedure. high yields of lpss were found in the phenol phase. gel electrophoresis of the phenol phase lpss showed similar patterns for all strains in contrast to the different patterns found in the water phase lpss. sugar composition was also similar among all strains with rhamnose as the predominant sugar. mannosamine was detected ...19892632669
expression of two conserved leptospiral antigens in escherichia coli.the genes encoding two protein antigens of leptospira interrogans serovar pomona were cloned and expressed in escherichia coli. rabbit antisera raised against the cloned proteins, designated p12 and p20, were used to identify the antigens in western blots of disrupted leptospiral cells. the proteins p12 and p20 were conserved within the genus leptospira and were not detected in leptonema illini. although both proteins were present in leptospiral outer envelope preparations they did not elicit th ...19892644433
effect of vaccination with a pentavalent leptospiral vaccine on leptospira interrogans serovar hardjo type hardjo-bovis infection of pregnant cattle.effectiveness of a pentavalent leptospiral vaccine to protect cattle from infection and reproductive problems caused by leptospira interrogans serovar hardjo type hardjo-bovis was evaluated. seven cows were vaccinated once and 8 cows were vaccinated twice with a usda-licensed pentavalent leptospiral vaccine. five cows were maintained as nonvaccinated controls. cows were bred 1 to 2 months after the last vaccination. during the 4th to 6th month of gestation, all cows were challenge exposed on 4 o ...19892645816
[leptospirosis in cattle; milker's fever in cattle farmers].in this paper the symptomatology, epidemiology, and diagnosis of leptospira interrogans serovar hardjo infections in cattle are reviewed. the possibilities on monitoring and control of this disease in both foreign countries and the netherlands are discussed. special attention is paid to the zoonotic aspects of the infection (dairy fever).19892646755
hideyo noguchi's research on yellow fever (1918-1928) in the pre-electron microscopic era.one of the low points in hideyo noguchi's career as a pioneer medical microbiologist was his investigations on yellow fever between 1918 and 1924 in central and south america. his discovery that spirochete leptospira icteroides was the causative pathogen of yellow fever was discredited in 1927. this paper evaluates the situation under which noguchi conducted his experiments and assesses the causes which might have resulted in his erroneous interpretation in the pre-electron microscopic era. even ...19892671469
comparison of three techniques to detect leptospira interrogans serovar hardjo type hardjo-bovis in bovine urine.nucleic acid hybridization, bacteriologic culture, and a fluorescent antibody test were compared for detection of leptospira interrogans serovar hardjo type hardjo-bovis in bovine urine. seventy-five urine samples were collected from pregnant cows challenge exposed with type hardjo-bovis. twenty samples were collected from steers not exposed to hardjo-bovis. sediments from each sample were examined, using fluorescent antibodies and a repetitive sequence element nucleic acid probe, to detect the ...19892672910
isolation techniques for spirochetes and their sensitivity to antibiotics in vitro and in vivo.leptospira interrogans can be cultured from blood and cerebrospinal fluid during the first week of leptospirosis and from urine thereafter. studies of in vitro sensitivity indicate that these organisms are sensitive to most antibiotics. tetracycline and penicillin g are most often used clinically, although laboratory studies suggest that the bactericidal activity of penicillin g may be inadequate. treponema pallidum cannot be satisfactorily cultured. it is identified by dark-field microscopy. st ...19892682963
an application of monoclonal antibodies to identification of leptospires of serogroup icterohaemorrhagiae found in china.for the purpose of improving the procedures of identification of leptospires, a set of 5 monoclonal antibodies with different serological reactivity against serovars of leptospira interrogans icterohaemorrhagiae serogroup isolated in china was developed. one hundred and eight strains isolated from epidemic fields in 5 provinces in southern china were distinctly identified into 4 serovars of icterohaemorrhagiae serogroup by the monoclonal antibody procedure, i.e., 98 isolates were identified as s ...19892695789
genetic and antigenic characterization of borrelia coriaceae, putative agent of epizootic bovine abortion.borrelia coriaceae was characterized genetically and antigenically by utilizing the following techniques: restriction endonuclease analysis, southern blotting and genomic hybridization, pulsed-field electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunoblotting. the b. coriaceae genome revealed unique and characteristic banding patterns both by agarose gel electrophoresis and by hybridization when compared with several borrelia burgdorferi isolates. pulsed-field g ...19892715314
experimental immunisation of hamsters with lipopolysaccharide antigens of leptospira interrogans.hamsters were immunised with leptospiral lipopolysaccharide (lps) or the polysaccharide (ps) fraction of lps from leptospira interrogans serovar copenhageni and the antibody responses were measured by agglutination tests. maximum titres were observed approximately 6 weeks after immunisation and protection against lethal challenge with the homologous strain was afforded by immunisation with as little as 2.5 micrograms of lps or ps. all animals produced igm agglutinins but a higher proportion of-a ...19892733021
monoclonal antibody against leptospira interrogans serovar canicola.nine cell lines producing monoclonal antibodies (mabs) against leptospira interrogans serovar canicola strain moulton were established by the cell fusion technique. the immunological reactivity of these mabs with various kinds of serogroups, serovars and strains were examined by microscopic agglutination test (mat) and enzyme-linked immunosorbent assay (elisa). mabs w1-w3 derived from mice, which were immunized with whole cells of the strain moulton, reacted with the serogroups canicola, icteroh ...19892743485
immunological characteristics of the glycolipid antigen of leptospira interrogans serovar lai.the protective antigen (pag), a glycolipid substance, was extracted from leptospira interrogans serovar lai strain 017 with a chloroform-methanol-water (1:2:0.8 [vol/vol/vol]) solution and partially purified by silica gel column chromatography. the pag was not detected by coomassie brilliant blue staining in sodium dodecyl sulfate-polyacrylamide gel electrophoresis but was observed as a smearlike band, which corresponded to a 24- to 30-kilodalton standard protein, by silver staining. the outer e ...19892744857
cloning of a hemolysin gene from leptospira interrogans serovar hardjo.a dna fragment encoding both hemolysin and sphingomyelinase c activity was cloned from the pathogenic bacterium leptospira interrogans serovar hardjo. initial clones were obtained by screening a genomic library in embl3 for hemolytic activity. both hemolytic and sphingomyelinase c activities were coded for by a 3.9-kilobase bamhi fragment. the hemolysin was expressed from its own promoter in escherichia coli k-12. similar dna sequences were also present in the serovars tarassovi and ballum.19892744864
efficacy of ciprofloxacin against leptospira interrogans serogroup icterohaemorrhagiae.ciprofloxacin activity against leptospira interrogans serogroup icterohaemorrhagiae was studied in vitro and in an animal model. the mbc of ciprofloxacin was 0.6 microgram/ml. three of three syrian hamsters died 8 to 9 days after intraperitoneal challenge with 10(6) leptospires. in contrast, five of six animals given ciprofloxacin 3 or 5 days after challenge survived.19892751290
diagnostic specificity, sensitivity and cross-reactivity of an enzyme-linked immunosorbent assay for the detection of antibody against leptospira interrogans serovars pomona, sejroe and hardjo in cattle.outer sheath antigen was prepared from leptospira interrogans serovars pomona, sejroe and hardjo by treating the organisms with 1.0m nac1 followed by 0.04% sodium dodecyl sulfate (sds). sodium dodecyl sulfate was removed from the sds-protein complexes by the extraction of dodecyl sulfate anions as ion pairs with triethylammonium cations into an organic solvent. the outer sheath antigen was recovered from the organic solvent as a precipitate and used as the source of leptospiral enzyme-linked imm ...19892766149
severe disease in a dairy herd associated with acute infection with bovine virus diarrhoea virus, leptospira harjo and coxiella burnetii.between november 1984 and february 1985, a serious outbreak of pyrexia, diarrhoea, agalactia, metritis and severe weight loss affected most of the recently calved cows in a 183-cow dairy herd in norfolk. fifteen cows died and 20 were culled. forty cows aborted during or after the outbreak, and many of them produced mummified fetuses; 18 calves were stillborn and three others died soon after birth. necropsy of three affected cows revealed ulceration of the gastrointestinal tract similar to that s ...19892773203
effect of vaccination with a bacterin containing leptospira interrogans serovar bratislava on the breeding performance of swine herds.swine herds suspected to be infected with leptospira interrogans serovar bratislava were vaccinated with bacterins containing 5 or 6 leptospiral serovars in which serovar bratislava was the unique component. the principal diagnostic feature indicating an infection by this organism was demonstration of antibody against serovar bratislava in sera from stillborn pigs. for 1 breeding cycle after vaccination of herds on 3 farms, 255 of 266 (95.9%) sows and gilts given the 6-serovar bacterin farrowed. ...19892774321
effects of leptospiral lipopolysaccharide on rabbit platelets.leptospiral lipopolysaccharides (lpss) extracted from leptospira interrogans serovar copenhageni virulent strain shibaura, serovar canicola virulent strain moulton, and serovar hebdomadis strain hebdomadis, were tested for their ability to induce platelet aggregation and/or lysis in rabbit platelet-rich plasma (prp). all showed positive reactions with a release of adenosine triphosphate (atp) and serotonin. the values, however, were different from each other. the ability of leptospiral lps extra ...19892775427
detection of antibodies to leptospirosis in experimentally infected dogs using the microcapsule agglutination test.six puppies were infected with a virulent strain of leptospira interrogans serovar icterohaemorrhagiae and another five animals with a virulent strain of leptospira interrogans serovar canicola, respectively. antibodies were examined at 3, 5, 7, 11 and 14 days after infection, using the microcapsule agglutination test (mcat) and the conventional microscopic agglutination test (mat). compared with the mat, the mcat detected early specific igm antibody with high sensitivity. the mcat titres reache ...19892775983
an immunoprotective monoclonal antibody directed against leptospira interrogans serovar copenhageni.a monoclonal antibody (mab) was prepared by hybridoma technology in balb/c mice immunized to leptospira interrogans serovar copenhageni. this mab agglutinated serovars copenhageni and icterohaemorrhagiae to high titres and protected hamsters, dogs and monkeys against challenge with a virulent strain of serovar copenhageni. the mab gave protection to hamsters at dilutions up to 1 in 1000; at a 1 in 10 dilution the protective effect lasted for at least two weeks. biochemical analysis by sds-page a ...19892778433
clinical leptospira interrogans serogroup australis serovar lora infection in a stud farm in the netherlands.a leptospira interrogans serogroup australis serovar lora infection in a stud farm is reported. during three successive years (1984-1986) clinical leptospirosis with a severe often rapid, fatal course was seen in 12 foals. clinical examination revealed severe respiratory distress, depression and pyrexia. other symptoms were diarrhea (2), jaundice (1), and an unsteady gait (1). morphological characteristics of the disease were massive pulmonary haemorrhage and haemorrhagic-thrombotic or extracapi ...19892781710
restriction endonuclease analysis of australian isolates of leptospira interrogans serovar hardjo. 19892789036
distribution of leptospirosis among stray dogs in the okinawa islands, japan: comparison of the microcapsule and microscopic agglutination tests.three hundred and thirty-eight sera collected from stray dogs in the okinawa islands were examined for antibodies against leptospira interrogans using the microscopic agglutination test (mat) and the one-point microcapsule agglutination test (mcat). seventy-eight sera (23%) showed a positive reaction to at least one of the six serovar antigens, and 69 of these reacted with serovar canicola by microcapsule agglutination test. the mixed microcapsule agglutination test detected 68 of the microscopi ...19892790440
pathogenesis of renal lesions in haemoglobinaemic and non-haemoglobinaemic leptospirosis.hamsters were infected with leptospira interrogans serovar ballum or leptospira interrogans serovar pomona and the kidney lesions were compared by light and electron microscopy. ballum and pomona both caused severe clinical signs and death within 6 days in some animals, although only ballum was associated with red blood cell destruction and haemoglobinaemic nephrosis. with ballum infections it is difficult to distinguish degenerate changes resulting from leptospiral "toxins" from those resulting ...19892794156
an experimental study with a leptospira interrogans serovar bratislava vaccine.the intramuscular vaccination of pigs with two doses, two weeks apart, of a leptospira interrogans serovar bratislava bacterin, protected pigs against renal infection when challenged with bratislava strains six weeks later but did not protect pigs challenged after 26 weeks.19892800262
characterization of trypsin extractable antigens of leptospira interrogans serovars pomona, bataviae & l. biflexa serovar patoc.leptospira strains after treatment with trypsin released an antigen (tx) which consisted of protein (4.2 mg/ml), carbohydrate (0.39 mg/ml) and hexosamine (0.025 mg/ml). immunodiffusion, immunoelectrophoresis and indirect haemagglutination tests revealed serological cross reactions among the three strains used. inhibition of microscopic agglutination reaction by the tx antigen was observed in homologous system only. the antigen was partially sensitive to heat (80 degrees c for 10 min) as detected ...19892807430
unique organization of leptospira interrogans rrna genes.we cloned sau3ai fragments containing the rrna genes for leptospira interrogans serovar canicola strain moulton in the bamhi site of lambda embl3 bacteriophage dna. physical maps of the fragments were constructed, and the locations of the rrna genes were determined by southern blot hybridization and s1 protection. each fragment of the 23s or the 16s rrna gene contained at least one copy of the 23s or the 16s sequence. genomic hybridization showed that there were two genes for the 23s rrna and th ...19892808297
leptospira interrogans serovar hardjo is not a major cause of bovine abortion in victoria.the aim of this study was to determine whether evidence could be obtained of foetal infection with leptospira interrogans serovar hardjo in aborted foetuses collected from dairy farms. material from 197 abortions occurring over a wide area of victoria was collected over 3 years. none of 195 foetal kidney cultures or 7 cultures from membranes was positive for leptospiral organisms. immunogold silver staining for leptospires was performed on sections of kidneys, lungs or heart from 156 foetuses, w ...19892818362
demonstration of antigen-specific t cells and histopathological alterations in mice experimentally inoculated with borrelia burgdorferi.antigen-specific t-cell responses and histopathological changes were studied in mice experimentally inoculated with borrelia burgdorferi b31. inbred mice with different h-2 haplotypes and/or different genetic backgrounds were inoculated with b. burgdorferi organisms and tested for antigen-specific t-cell responses in vivo (delayed-type hypersensitivity [dth]) and in vitro (t-cell proliferation). comparable dth responses were found after inoculation with either inactivated (in the presence of adj ...19892462540
evidence for sheep as a maintenance host for leptospira interrogans serovar hardjo. 19892922905
restriction endonuclease dna analysis of leptospira interrogans serovars icterohaemorrhagiae and copenhageni.leptospira interrogans serovar icterohaemorrhagiae strains ictero no. i and rga and serovar copenhageni strains m20, shiromizu and shibaura were examined by restriction endonuclease dna analysis. fifteen endonucleases (alui, bamhi, bglii, ecori, haeiii, hhai, hindiii, kpni, psti, saci, sali, smai, styi, xbai and xhoi) were used as the digesting enzymes. strain ictero no. i showed endonuclease cleavage patterns which differed from those of the other four strains only when it was digested with enz ...19882850447
hemolysin production by leptospira interrogans serovar canicola in a protein-free medium with hemin.leptospira interrogans serovar canicola strain moulton was grown to a high cell density in a protein-free medium. when hemin was added to this medium, hemolysin was produced. hemolysin was not detected when other porphyrins or cytochrome c were substituted for hemin in the medium.19882852404
restriction endonuclease dna analysis of antigenic variants of leptospires selected by monoclonal antibodies.the genome of antigenic variant cv (ct3)-1 derived from leptospira interrogans serovar canicola was compared by cleavage with restriction endonucleases with the parent and serovar bafani, to which the variant was serologically most closely related. no differences were observed between the parent and variant in dna restriction endonuclease patterns using eight restriction endonucleases. serovar bafani was different in the patterns from the parent and antigenic variant cv (ct3)-1. the two antigeni ...19882852766
leptospiral lipopolysaccharide presence in the outer envelope: electrophoretic evidence and immunological specificity.purified preparations of lipopolysaccharides (lps) extracted from two different strains of leptospira interrogans have been electrophoretically analyzed in order to determine their location at the level of outer envelope (oe). evidence has been collected for the presence of some lps fractions in the oe, suggesting that a part of this molecule is embedded in the membrane structure. the serological specificity of the lps has been in addition tested by means of monoclonal antiserovar antibodies (mo ...19882464258
serological survey for selected diseases in the endangered san joaquin kit fox (vulpes macrotis mutica).blood from endangered san joaquin kit foxes (vulpes macrotis mutica) inhabiting the elk hills naval petroleum reserve, kern county, and the elkhorn plain, san luis obispo county, california, was collected in 1981, 1982 and 1984 and sera were tested for antibodies against 10 selected pathogens. proportions of kit fox sera containing antibodies against pathogens were: canine parvovirus, 100% in 1981-1982 and 67% in 1984; infectious canine hepatitis virus, 6% in 1981-1982 and 21% in 1984; canine di ...19882836636
restriction endonuclease analysis of leptospira interrogans serovar hardjo isolates from cattle.the genomes of 253 strains of leptospira interrogans serovar hardjo were examined by restriction endonuclease analysis of their dna. the strains had been isolated from cattle at an abattoir (190), milk of agalactic cows (seven) and from aborted bovine fetuses (56). two distinct genome types, hardjoprajitno and hardjobovis, were detected. the majority (91 per cent) of isolates from abattoir cattle were of the hardjobovis type while most (76 per cent) of the isolates from clinical/pathological mat ...19882841734
presence of a variety of antigenic variants belonging to at least 4 different serovars in a population of leptospira interrogans serovar hebdomadis.the presence of antigenic variants belonging to at least 4 different serovars, jules, kremastos and 2 new serovars, was demonstrated in a population of cloned leptospira interrogans serovar hebdomadis. thirteen antigenic variants were isolated from the clone of serovar hebdomadis by culturing in the presence of 13 monoclonal antibodies against 5 serovars, hebdomadis, worsfoldi, kambale, jules and kremastos kyoto, respectively. these variants were divided into 4 groups, based on the reactivity wi ...19883176752
chemical and biological properties of a phenol-water extract from leptospira interrogans. evidence for the absence of lipopolysaccharide.leptospira interrogans, serovar copenhageni was extracted by the phenol-water method and the resulting preparation examined for chemical composition and endotoxic activity. chemical analysis revealed that a number of sugars were present, however, the amount of lipid content was very low. further, the preparation was devoid of characteristic endotoxic properties, like lethal toxicity, pyrogenicity and the property to induce the local shwartzman reaction. the extract, however, was active in the li ...19883182088
dna hybridization with hardjobovis-specific recombinant probes as a method for type discrimination of leptospira interrogans serovar hardjo.restriction endonuclease analysis of dna of leptospira interrogans, serovar hardjo, showed two distinct types within this serovar. these two types, hardjoprajitno and hardjobovis, cannot be differentiated by monoclonal antibodies. application of 32p- or biotin-labelled total dna probes in dot-blot or in situ hybridization assays showed a high sensitivity of the assays but also considerable cross-hybridization. therefore, a genomic library of hardjobovis was constructed and a number of hardjobovi ...19883183617
prevention of leptospira interrogans serovar pomona infection in domestic pigs by vaccination. 19883190600
serological reactions to leptospira species in game animals of northern natal.fifty sera collected from 12 different species of free-living game animals in game parks in the northern natal were tested against 8 leptospira interrogans antigens using the microscopic agglutination test (mat). six out of 50 animals had titres, all less than 100. three of these animals had titres to serovar mini, 1 animal to tarrasovi, and 3 animals had multi-serovar reactions, 1 to mini and hardjo, and 1 to tarrasovi, copenhageni and pomona.19883194123
comparative studies of strains ictero no. i and rga as the type strain of leptospira interrogans: agglutinin absorption test, protein and antigen profiles, and enzyme activities.strain ictero no. i, the first isolate of leptospira, isolated by inada and ido in 1914, was found to be sufficiently qualified to be the type strain of leptospira interrogans rather than strain rga. in an agglutinin absorption test, anti-ictero no. i serum was not absorbed completely with strain rga, and 25% of the homologous titer remained unabsorbed, while anti-rga serum was completely absorbed with strain ictero no. i. thus, strain ictero no. i was not serologically identical with strain rga ...19883200169
repetitive sequence element cloned from leptospira interrogans serovar hardjo type hardjo-bovis provides a sensitive diagnostic probe for bovine leptospirosis.a repetitive sequence element was cloned from the primary etiological agent causing bovine leptospirosis in north america, leptospira interrogans serovar hardjo type hardjo-bovis. this element was used to design a sensitive diagnostic probe which distinguishes hardjo-bovis from other pathogenic leptospires which commonly infect domestic animals in north america and discriminates between hardjo-bovis and the reference strain for serovar hardjo, hardjoprajitno. by using this probe, it was possible ...19883230128
classification of leptospira interrogans serovar lai strain 017 by using monoclonal antibodies.leptospira interrogans serovar lai was identified in china in 1966 as a new serovar of the icterohaemorrhagiae serogroup by cross-absorption tests. in this study, we established three hybridoma cell lines producing monoclonal antibodies (mabs) of the immunoglobulin g3 subclass (lw1, lw2, and lw3) and of the immunoglobulin m class (lw4a) against serovar lai strain 017 by the cell fusion technique. immunological reactivities of the mabs were determined by the microscopic agglutination test, enzyme ...19883235658
variation in the hemolytic activity of leptospira interrogans serovar canicola.leptospira interrogans serovar canicola strain moulton was grown to a high cell density in a protein-free medium with hemin. the hemolysin produced in this culture system showed a greatly expanded spectrum of hemolysis as compared to previous reports of leptospiral hemolysin produced in a more traditional culture system containing serum.19883238474
ménétrier's disease. a trivalent gastropathy.current conceptions of ménétrier's disease only obliquely resemble those originally described. bona-fide cases are so uncommon that, of 125 cases diagnosed as ménétier's disease, hypertrophic gastritis, or protein-losing gastropathy treated at the massachusetts general hospital during the 26-year period of 1962-1987, only six cases merited an unequivocal anatomic diagnosis. two other cases previously described proved on review to be nondiagnostic in one instance and campylobacter pylori gastriti ...19883264139
antigens recognised by the human immune response to infection with leptospira interrogans serovar hardjo.serum samples from patients infected with leptospira interrogans serovar hardjo were tested by the microscopic agglutination test (mat), enzyme immunoassay (eia) and immunoblotting. there was no apparent correlation between mat titre and eia optical density (od) for individual serum samples, but sequential serum samples produced similar profiles in both tests during the course of an infection. immunoblotting of hardjo sonicate with patients' sera revealed reactions with a number of bands, in the ...19883282073
identification of leptospiral flagellar antigens by gel electrophoresis and immunoblotting.flagella extracted from five serovars, representative of the pathogenic and saprophytic species of the leptospiraceae, were morphologically similar. analysis of leptospira interrogans flagellar preparations by polyacrylamide gel electrophoresis revealed three common major bands in the (30-40) x 10(3)-mol. wt region, and serovar-specific bands in the lower region of the gels. although some differences were observed, flagella extracted from l. biflexa serovar patoc and leptonema illini revealed si ...19883286874
the bacteriological prevalence of leptospiral infection in cattle and buffaloes in west malaysia.a cross-sectional bacteriological survey of cattle in west malaysia revealed 14.4% (32/222) had leptospiral infection. isolates were obtained from all except one herd with prevalence of infection in herds ranging from 0-44.8%. a small number of buffalo urine samples were examined and all of them were found to be negative. a leptospiral isolate obtained from a bovine kidney proved to be a new serovar of leptospira interrogans and the name unipertama was assigned to it. six other leptospiral serov ...19883356222
seroprevalence and association with abortion of leptospirosis in cattle in ontario.sera were collected using a systematic random sampling from 348 cattle herds in ontario, in proportion to the cattle population in different areas. one cow in five from 296 dairy herds and one in three from 52 beef herds were sampled. the sera were analyzed for prevalence of antibodies to leptospira interrogans serovar grippotyphosa, hardjo, icterohaemorhagiae and pomona using the microscopic agglutination test. herd seroprevalence (one or more animals with titer greater than or equal to 80) in ...19883370556
antimicrobial drug susceptibility of leptospira interrogans serovar hardjo isolated from cattle.the susceptibility to commonly used drugs of 18 isolates of leptospira hardjo from the kidneys of feedlot cattle from different sources was determined quantitatively. all isolates were susceptible to penicillin g, ampicillin, tetracycline, erythromycin and streptomycin. susceptibility to sulphamethazine was ambiguous. no drug resistance was detected and the results were similar to those described for other serovars.19883370565
leptospires in the marine toad (bufo marinus) on barbados.leptospires were isolated from the kidneys of four of 211 toads (bufo marinus) caught on barbados. two of the isolates were identified as leptospira interrogans serovar bim in the autumnalis serogroup (the most common cause of leptospiral illness on barbados), and two as possibly new serovars in the australis serogroup. sera from 198 of the toads were examined by the leptospire microscopic agglutination test. forty-two (21%) were positive at titers of greater than or equal to 1:100, and 54 (27%) ...19883373639
opsonic effect of monoclonal antibodies against leptospira interrogans serovar copenhageni.the opsonic effect of monoclonal antibodies (mcabs) against leptospira interrogans serovar copenhageni strain shibaura was examined in vitro using radiolabeled organisms and mouse peritoneal exudate macrophages. four igg mcabs (all igg3) and 2 igm mcabs were used, all showed different reactivities and were bound to homologous lipopolysaccharide (lps). igg3 mcabs at the sub-agglutinating concentration were opsonic, but the degree of the opsonic effect varied among igg3 mcabs. opsonization with ig ...19883376416
human-to-human transmission of leptospira interrogans by milk. 19883392418
bovine leptospirosis: microbiological and histological findings in cattle at slaughter.kidneys from cattle at slaughter were examined for the presence of leptospires. of 218 (8.3%) kidneys leptospires were isolated from 18; all were identified as leptospira interrogans serovar hardjo. none of the leptospire-infected kidneys had histopathological lesions indicative of leptospirosis and leptospires were demonstrated in only 2 by immunogold silver staining. leptospires infected kidneys remained viable for at least 21 days when stored at 4 degrees but became non-viable within 14 days ...19883401146
[swine leptospirosis. first isolation in chile of leptospira interrogans serovar tarassovi]. 19883420981
reaction of monoclonal antibodies with species specific determinants in leptospira interrogans outer envelope.a set of 24 monoclonal antibodies (mabs) was produced against an outer envelope preparation from leptospira interrogans serovar copenhageni. the mabs reacted in enzyme immunoassay with species-specific determinants of an antigen in the leptospiral outer envelope (oe) of pathogenic but not of saprophytic species of leptospira. the mabs did not agglutinate whole leptospires, nor could they opsonise homologous leptospires for phagocytosis by mouse macrophages or protect new-born guinea-pigs against ...19882459387
expression of antigen genes of leptospira interrogans serovar canicola in escherichia coli.leptospira interrogans serovar canicola dna was cloned into the plasmid pbr322 and introduced into e. coli. eight out of approximately 10,000 transformants were found to express antigens of canicola by elisa including colony elisa blot test using anti-canicola antiserum. the canicola antigens expressed in the transformants reacted with the antisera against the serovars belonging to canicola serogroup and other serogroups of l. interrogans. they did not react, however, with the antiserum against ...19883070308
leptospiral antibodies in cattle in alberta and evidence of an emerging serovar.antibodies to leptospira interrogans serovars hardjo and pomona were present in 8.3% and 0.5% of sera respectively, from adult female cattle in alberta surveyed in 1984-85. criterion for a positive serum sample was 50% agglutination at 1/100 dilution in the microscopic agglutination test. a positive herd contained one or more cows with positive serum. prevalences were calculated on sample sizes that would give 80-95% reliability. hardjo antibody prevalences and hardjo-positive herd prevalences w ...198817423101
serologic survey for selected microbial pathogens of wolves in alaska, 1975-1982.serum samples were collected from 116 wolves which were captured in southcentral alaska during 1975 through 1982. antibodies to the following infectious disease agents were found: infectious canine hepatitis virus-72 of 87 (81%), canine parvovirus type 2-0 of 55 (0%) through 1979 and 10 of 32 (31%) after 1979, francisella tularensis-16 of 67 (25%), canine distemper virus-10 of 83 (12%), coxiella burnetti-5 of 95 (5%), rabies virus-1 of 88 (1%), brucella spp.-1 of 67 (1%), leptospira interrogans- ...19873029442
biological activities of lipopolysaccharide-like substance (lls) extracted from leptospira interrogans serovar canicola strain moulton.the biological activities of lipopolysaccharide-like substance (lls) extracted from leptospira interrogans serovar canicola strain moulton by the hot phenol-water method were studied in mice. the addition of 12.5 micrograms/ml or more of lls fraction increased the incorporation of [3h]thymidine into in vitro cultured spleen cells of c57bl/6 mice, while the activity of the lls fraction was about 20 times weaker than that of salmonella typhimurium lipopolysaccharide (lps). pretreatment of murine s ...19873500390
effect of heat or chemical treatment on leptospiral antigens.the use of bacterins is one of the primary methods in the control of leptospirosis in domestic animals, especially cattle, swine, and dogs. bacterins have been made using chemically treated or heat-inactivated organisms. many of the initial studies indicated that the bacterins gave complete protection, whereas later reports found that some inactivation methods resulted in bacterins that protect against death but not against kidney infection and renal shedding. this raised the possibility that so ...19873818922
opsonic monoclonal antibodies against lipopolysaccharide antigens of leptospira interrogans serovar hardjo.six monoclonal antibodies produced from mice immunised with leptospira interrogans serovar hardjo were directed against determinants in the leptospiral lipopolysaccharide, as indicated by immunodiffusion and enzyme immunoassay (eia), and opsonised leptospires for phagocytosis by mouse macrophages. their specificities were studied by agglutination and eia. five antibodies reacted with some, but not all, members of the sejroe and hebdomadis serogroups, and one antibody agglutinated exclusively mem ...19873820267
serology and virology of the bowhead whale (balaena mysticetus l.).sera from four bowhead whales (balaena mysticetus l.) were examined for the presence of specific antibodies, and tissue and swab samples from six and four animals respectively were processed for isolation of viruses and for initiation of bowhead whale cell cultures. all sera were negative for antibodies to nine serovars of leptospira interrogans and to 21 orthomyxovirus subtypes and a paramyxovirus (newcastle disease virus). all sera were positive, however, for neutralizing antibodies to one or ...19873820430
serological survey of leptospiral antibodies in cattle in zimbabwe.a total of 2,382 sera from 92 herds widely distributed throughout zimbabwe were screened using the microscopic agglutination test against representatives of 18 serogroups of leptospira interrogans and one representative of leptospira biflexa. the prevalence of leptospiral titres at a serum dilution of 1:100 was 27%, the most common titres being to antigens from the sejroe and tarassovi serogroups. significantly different proportions of titres were shown among the three farming systems and among ...19873424449
detection of leptospires in biological fluids using dna hybridisation.dna extracted from leptospira interrogans serovar pomona was labelled with phosphorus-32 by nick translation and used as a genomic probe to detect leptospiral dna. the sensitivity of detection in a 10-microliter spot on nylon membranes was 160 pg of leptospiral dna or 1.1 x 10(3) leptospires and assays with nylon membranes were somewhat more sensitive than assays with nitrocellulose membranes. the probe reacted with the pathogenic hardjo and tarassovi leptospiral serovars, but not with other gen ...19873439017
effect of maternal vaccination on the susceptibility of growing pigs to leptospiral infection.serum samples were collected from 30 piglets, derived from 17 litters, whose dams had been vaccinated against leptospirosis. microscopic agglutination test (mat) titres against leptospira interrogans serovar pomona varied greatly from pig to pig; there was less variation among littermates. titres declined between 4 and 10 weeks of age, with an uncorrected half-life of 15.5 days, consistent with igg being the main antibody class involved. twelve pigs, 4 derived from unvaccinated sows and 8 from s ...19873439018
leptospiral attachment to extracellular matrix of mouse fibroblast (l929) cells.the attachment of leptospires to the extracellular matrix (ecm) remaining after mouse fibroblast (l929) cells on coverslips had been solubilized with triton x-100 was examined. each highly virulent line of leptospira interrogans serovar copenhageni, canicola and pomona attached to ecm more effectively than intermediately virulent and avirulent lines of the same strains, suggesting a correlation between virulence and attachment to ecm. inhibition of the attachment of highly virulent copenhageni t ...19873439019
molecular comparison of antigens and proteins of virulent and avirulent clones of leptospira interrogans serovar copenhageni, strain shibaura.the antigens and the protein profiles of virulent and avirulent clones of leptospira interrogans serovar copenhageni, strain shibaura were compared by sds-polyacrylamide gel electrophoresis (sds-page), western blotting and radioimmunoprecipitation. an antigen specific to the virulent clone was detectable only in the virulent clone by western blotting using anti-virulent clone but not anti-avirulent clone antisera. the molecular weight of the antigen was estimated to be approximately 32000 by sds ...19873439384
cross-reactivity in serological tests for lyme disease and other spirochetal infections.serum specimens from 163 persons with lyme disease, tick-borne or louse-borne relapsing fever, yaws, syphilis, leptospirosis, or rocky mountain spotted fever were analyzed to assess the specificity of indirect fluorescent antibody (ifa) tests, an enzyme-linked immunosorbent assay (elisa), and microscopic agglutination (ma) procedures. strong cross-reactivity occurred when sera from individuals with lyme disease, tick-borne relapsing fever, and louse-borne relapsing fever were tested against hete ...19873298452
genus-specific antigens in leptospira revealed by immunoblotting.immunoblotting of leptospiral sonicates with heterologous rabbit antisera revealed a distinct cross-reactive pattern which differed with respect to the pathogenic and non-pathogenic leptospiral serovars, and that all serovars tested from leptospira interrogans, l. biflexa and l. illini contained a common 35 kilodalton (kd) band. a leptospiral genus-specific antigen preparation produced by ethanol fractionation of l. biflexa serovar patoc reacted by enzyme immunoassay (eia) with all heterologous ...19873310456
leptospirosis in horses in ontario.sera from thoroughbred and standardbred horses in southwest ontario were tested for antibody to seven leptospira interrogans serovars (autumnalis, bratislava, canicola, grippotyphosa, hardjo, icterohaemorrhagiae, pomona), using the microscopic agglutination test. there was significantly higher seroprevalence of bratislava than of other serovars, in which prevalence was low. seroprevalence of bratislava increased significantly with age; only 5% of two to three year old horses had titers greater t ...19873330964
selection of antigenic variants from leptospira interrogans serovar canicola by means of anti-canicola monoclonal antibody.antigenic variants were isolated from canicola by a single selection with anti-canicola monoclonal antibody ct-3. the variants were not identical to any serovars of serogroup canicola and thought to be a new serovar. variation frequency was calculated at 5.9 x 10(-4). the usefulness of monoclonal antibodies for selection of antigenic variants of leptospiras is discussed.19872445125
enzyme activities of the strains belonging to family leptospiraceae detected by the api zym system.a total of 32 strains of the family leptospiraceae (23 strains of leptospira interrogans, 6 strains of leptospira biflexa, 2 strains of leptonema and 1 strain of leptospira parva) were examined for enzyme activities using 89 substrates (api zym system). more than 90% of the strains belonging to the family leptospiraceae possessed strong activities of beta-d-galactosidase, beta-d-glucosidase and 5 esterases (c5, c6, c8, c9 and c10). more than 90% of the strains belonging to the genus leptospira, ...19872892326
molecular cloning of treponema pallidum outer envelope fibronectin binding proteins, p1 and p2.phages directing the synthesis of treponema pallidum fibronectin binding adhesin proteins, p1 and p2, were isolated from an embl-3 bacteriophage lambda library of t pallidum deoxyribonucleic acid (dna). the recombinant phages were identified using antisera generated to treponemal proteins purified in fibronectin-sepharose. recombinant p1 and p2 proteins possessed the same relative molecular weights as the native surface polypeptides of spirochaetes. the structural genes for these proteins were s ...19872962928
experimental infection of monkeys with leptospira interrogans serovar hardjo.grivet monkeys experimentally infected with two different strains of leptospira interrogans serovar hardjo showed no signs of severe clinical disease. there were no significant macroscopic lesions in any of the tissues examined, but the organisms were demonstrated in various tissues by immunofluorescent technique and were isolated from the blood and urine of two monkeys and the kidney of one. abraded skin was shown to be a viable route of infection in non-human primates.19873549342
tears and aqueous humor from horses inoculated with leptospira contain antibodies which bind to cornea.an antigenic relationship between leptospira interrogans and equine cornea was previously described by us. an enzyme-linked immunosorbent assay was employed in the present work to investigate the existence of anti-leptospira and anti-cornea antibodies in tears, aqueous humor and serum from horses inoculated i.m. with those antigens. ten days after a booster by the same route, antibodies that bind to microtiter plates, coated with an homogenate of either equine cornea or leptospira, were detected ...19873564364
isolation of leptospires from nephritic kidneys of beef cattle at slaughter.of 955 beef cattle slaughtered at an abattoir in quebec from may to august 1985, 122 (13%) had lesions of focal interstitial nephritis. nephritic kidneys were collected for leptospiral culture, and matching blood samples were examined serologically. leptospires were isolated from the kidneys of 35 (29%) cattle. antibodies to leptospira interrogans serovar hardjo were found in 29 (24%) cattle and to pomona in 13 (10%).19873565891
prevalence of canine lyme disease from an endemic area as determined by serosurvey.from august 1984 through february 1985, 423 dogs from 43 municipalities in 7 new jersey counties were evaluated for the presence of antibodies to the lyme disease spirochete (borrelia burgdorferi). of these dogs, 34.7% with no apparent clinical symptoms were serologically reactive (ifa greater than or equal to 1:64); titers in this study ranged from non-reactive to 1:2048. ninety percent of the dogs surveyed had a current vaccination status to leptospira interrogans serovars canicola and icteroh ...19873591094
c-reactive protein in dogs.serum concentrations of c-reactive protein (crp) in dogs with various diseases or undergoing various procedures were measured by specific immunoassay. in 20 healthy dogs from various sources, values were all less than 5 mg/l, but in 22 healthy dogs from a single source, values ranged from less than 5 mg/l in 14 dogs and from 8 to 67 mg/l in 8 dogs. increased concentrations of serum crp were attained 24 hours after injection of casein (n = 9; median 188 mg/l), ovariohysterectomy (n = 11; median, ...19873605808
serological studies on british isolates of the sejroe serogroup of leptospira. ii. an evaluation of the factor analysis method of identifying leptospires using strains belonging to the sejroe serogroup.twelve british isolates of leptospira belonging to the sejroe serogroup were examined using a series of six factor sera prepared by a number of different absorption methods. ten of the isolates were identified as leptospira interrogans serovar hardjo and two as l. interrogans serovar saxkoebing. these isolates had previously been identified using the cross agglutination absorption method.19873609168
serological studies of british leptospiral isolates of the sejroe serogroup. iii. the distribution of leptospires of the sejroe serogroup in the british isles.some 94 strains of leptospires belonging to the sejroe serogroup isolated in the british isles were identified to the serovar level using specific factor sera. seventy strains were identified as leptospira interrogans serovar hardjo, 66 from cattle, 2 from pigs and 1 each from a sheep foetus and a human. twenty-four strains were identified as l. interrogans serovar saxkoebing, most strains were isolated from either wood mice, bank or field voles but strains were also isolated from badgers, a fox ...19873609169
the effects of gamma-irradiation on haemopoiesis and red blood cell destruction in hamsters infected with leptospira interrogans serovar ballum.irradiated hamsters were infected with leptospira interrogans serovar ballum in order to study the effects of impairment of the reticulo-macrophage system on the progression of the disease and the development of haemoglobinaemia. infected and irradiated hamsters were compared with infected controls, irradiated controls and untreated controls. red blood cells (rbcs) from untreated controls were biconcave disks while those from irradiated controls were echinocytes. red blood cells from animals of ...19873620332
the isolation of leptospira interrogans serovar pomona and related serological findings associated with a mixed farming unit in the transvaal.this is the first known isolation in the republic of south africa (rsa) of the serovar pomona from the organs of porcine foetuses as well as from the renal lymph nodes of slaughter pigs showing chronic nephritis. in addition, the serovar pomona was isolated from the kidneys of 87.5% of the slaughter pigs examined. the success of these isolations was attributed in part to the refining of 2 existing isolation techniques which complement each other. using the microscopic agglutination test, serum s ...19873627726
[studies on endotoxins of leptospira. iii. the presence of beta-hydroxy-myristic acid in the lps of leptospira interrogans serovar lai]. 19873630144
detection of leptospira interrogans in clinical specimens by in situ hybridization using biotin-labelled dna probes.in situ dna hybridization using biotin-labelled leptospiral dna was performed on clinical specimens to investigate its usefulness as a technique for the identification of leptospira interrogans. the applicability of this test in blood, urine and liver smears was demonstrated. in situ dna hybridization can be completed in only 4 h and it combines the advantage of visualization of the leptospiral morphology with the specificity of the hybridization reaction. no cross-hybridization was observed wit ...19873655736
purification, characterization and serological properties of a glycolipid antigen reactive with a serovar-specific monoclonal antibody against leptospira interrogans serovar canicola.a glycolipid antigen possessing a serovar-specific antigenic determinant of leptospira interrogans serovar canicola was purified from a chloroform/methanol extract of the organism. the purification procedures included silicic acid column chromatography and preparative thin-layer chromatography (tlc). antigenic activity was detected by a tlc-enzyme immunostaining technique using monoclonal antibody ct3, which specifically agglutinates serovar canicola and only weakly serovar sumneri but no other ...19873655741
a new serovar mogdeni of serogroup tarassovi of leptospira interrogans isolated from a sewage plant in england.among 30 strains of leptospires isolated from samples of sewage taken before and during treatment at two sewage plants in england, only one appeared to belong to leptospira interrogans, the species that comprises the leptospires that are pathogenic to man and animals. that strain, compton 746, was isolated from settled sewage, before treatment at a treatment plant that deals mainly with human sewage. it was shown serologically to belong to serogroup tarassovi and appears to represent a new serov ...19873678398
serological prevalence of leptospiral infection in domestic animals in west malaysia.a cross-sectional serological survey of domestic animals in west malaysia revealed that 25.5% of the animals examined had agglutinating antibodies to one or more antigens belonging to leptospira interrogans. significant prevalence of infection was observed in cattle (40.5%), buffaloes (31%) and pigs (16%). the sejroe serogroup was shown to be the principal one involved in cattle and buffaloes, and to a lesser extent the tarassovi and pomona serogroups. evidence of infection in domestic animals b ...19873678399
chemical properties of lipopolysaccharide-like substance (lls) extracted from leptospira interrogans serovar canicola strain moulton.the aqueous layer was isolated from leptospira interrogans serovar canicola strain moulton by the hot phenol-water method. after ultracentrifugation, the precipitate was designated as lipopolysaccharide-like substance (lls) fraction and the chemical composition was compared with that of bacterial lps. the lls fraction consists of 35.2% carbohydrate, 3.8% amino sugar, 36.4% lipid, 15.2% protein, and 0.3% phosphorus. neutral sugars were detected as rhamnose, arabinose, xylose, 4-o-methylmannose, m ...19873683216
serologic correlation of suspected leptospira interrogans serovar pomona-induced uveitis in a group of horses.after the observation of 2 horses with uveitis on a horse farm in the minnesota river valley, 100 horses from this geographic area were given ophthalmologic examinations and were evaluated serologically for leptospirosis. a statistically significant (p less than 0.001) association was observed between the finding of antibodies against leptospira interrogans serovar pomona and uveitis.19873693011
serologic survey for evidence of exposure to vesicular stomatitis virus, pseudorabies virus, brucellosis and leptospirosis in collared peccaries from arizona.two hundred eighteen usable serum samples were collected from hunter-killed collared peccaries (tayassu tajacu) during march 1986, in three areas of arizona. evaluations for antibodies against vesicular stomatitis virus (vsv) new jersey (nj) type, vsv indiana type, pseudorabies virus, brucellosis, and leptospirosis revealed positive test results in 8%, 0%, less than 1%, 0%, and 23% of the sera, respectively. exposure of peccaries to vsv (nj) was widespread, but variation in the prevalence of ser ...19872824864
dna probe for detection of the leptospira interrogans serovar hardjo genotype hardjo-bovis.a dna probe is described for the diagnostic and taxonomic identification of the north american cattle pathogen leptospira interrogans genotype hardjo-bovis. the probe is specific for this genotype and does not hybridize to genomic dna of any other leptospire pathogen commonly found in north america.19872826538
comparative classification of leptospira serovars of the pomona group by monoclonal antibodies and restriction-endonuclease analysis.the serovars of the pomona group of leptospira interrogans are antigenically closely related and can be classified only with difficulty by conventional typing methods. monoclonal antibodies (mcas) were prepared to serovars of the pomona group. the mcas were directed against antigens of polysaccharide nature. a battery of six mcas was selected for the classification of pomona group reference strains. these mcas could be used for the typing of all pomona group strains and unknown isolates. alterna ...19872830738
radiometric method for the rapid detection of leptospira organisms.a rapid and sensitive radiometric method for detection of leptospira interrogans serovar pomona and leptospira interrogans serovar copenhageni is described. stuart's medium and middlebrook tb (12a) medium supplemented with bovine serum albumin, catalase, and casein hydrolysate and labeled with 14c-fatty acids were used. the radioactivity was measured in a bactec 460 (johnston laboratories). with this system, leptospira organisms were detected in human blood in 2 to 5 days, a notably shorter time ...19863700624
ultrastructure and chemical composition of lipopolysaccharide extracted from leptospira interrogans serovar copenhageni.lipopolysaccharide (lps) from leptospira interrogans serovar copenhageni was prepared from the aqueous phase of a phenol/water extract. electron microscopic examination of negatively stained lps showed a mixture of ribbon-like, round and ring structures. carbohydrate analysis of the preparations revealed pentoses, hexoses, heptoses, hexosamines, and a 2-keto-3-deoxyonic acid which was chromatographically different from authentic 2-keto-3-deoxyoctonic acid (kdo). the major fatty acids of the lps ...19863711857
glycolipoprotein cytotoxin from leptospira interrogans serovar copenhageni.lipopolysaccharide (lps), glycolipoprotein (glp) and lipid extract were prepared from leptospira interrogans serovar copenhageni. glp, lipid extract or purified fatty acids from lipid extract produced cytotoxic effects seen as cell enzyme leakage followed by cytotoxic death when tested in mouse fibroblast l929 cells in tissue culture. all extracts also agglutinated mouse erythrocytes but purified lps was not cytotoxic. neither glp nor lps were pyrogenic but both gelled limulus amoebocyte lysate. ...19863711858
the detection of leptospires by a chemiluminescent immunoassay.rabbit serum hyperimmune to leptospira interrogans var icterohaemorrhagiae serovar icterohaemorrhagiae, reference strain rga was conjugated to the chemiluminescent label abei (6-[n-(4-aminobutyl)-n-ethyl amino]-2,3-dihydrophthalazine-1,4-dione) in the presence of the coupling agent, edc (1-ethyl-3(3-dimethyl amino-propyl)-carbodiimide hcl). the luminescent conjugate was incubated with homologous and heterologous antigens. the results indicate that chemiluminescence may provide an accurate and ra ...19863723587
serological studies on british leptospiral isolates of the sejroe serogroup. i. the identification of british isolates of the sejroe serogroup by the cross agglutinin absorption test.using the cross agglutinin absorption test 12 british leptospiral isolates of the sejroe serogroup were identified to serovar level. six strains isolated from cattle, two from pigs and one from a human were identified as leptospira interrogans serovar hardjo. two isolates from wildlife were identified as leptospira interrogans serovar saxkoebing. one further strain isolated from wildlife closely resembled serovar saxkoebing, but specific identification was not possible. these are the first repor ...19863734440
comparison of antibodies to leptospira in white-tailed deer (odocoileus virginianus) and cattle in ohio.a survey was conducted to determine the prevalence of leptospiral antibodies in sera from 248 white-tailed deer (odocoileus virginianus) in ohio. the sera were collected at check stations during the hunting season in 1983. the microscopic agglutination microtiter test was used to determine the presence of antibodies to leptospira interrogans serovars pomona, icterohemorrhagiae, canicola, hardjo, and grippotyphosa. eighteen of 248 (7.3%) serum samples had antibody titers (greater than or equal to ...19863735579
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