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the number of large ribosomal rna genes in leptospira interrogans and leptospira biflexa.we determined the number of large ribosomal rna genes in five strains of leptospira by hybridization of 15 restriction endonuclease digests of genomic dna to the [32p]-labeled fragment of 23s rrna gene. almost all the restriction gels gave two radioactive bands. the conclusion from these results is that there are at least two rrna genes in these leptospiral strains. furthermore, the hybridization patterns of l. icterohaemorrhagiae strains ictero no. i and rga are almost identical. the number of ...19892475749
monoclonal antibodies reacting with serogroup and serovar specific epitopes on different lipopolysaccharide subunits of leptospira interrogans serovar pomona.monoclonal antibodies with two kinds of specificities, produced against leptospira interrogans serovar pomona, were studied by agglutination and immunoblotting. antibodies reacted either exclusively with serovar pomona or with all members of the pomona serogroup, but none of the antibodies reacted with representative serovars of other serogroups. both antibodies recognized epitopes on purified lipopolysaccharide (lps) from serovar pomona. in immunoblotting experiments the serogroup specific anti ...19892483523
[in vitro sensitivity of 3 strains of leptospira interrogans to 3 different antibiotics].leptospirosis, anthropo-zoonosis ubiquitously widespread, is a social and economic problem still to be solved. the experimental and therapeutic employment of many antibiotics has largely been tested "in vitro" and "in vivo". in the following research we tried to evaluate, by experimental "in vitro" method, the sensitivity difference of three serovar strains of leptospira interrogans to two macrolides, erythromycin and josamycin, compared with penicillin. from standard cultures, previously treate ...19892491282
[studies on endotoxin of leptospira. v. the effect of edta-na on the release of the lps of leptospira interrogans serovar lai].the yield of leptospiral lps was able to increase 1-2 times when the cells were treated with edta-na before extracting with hot phenal-water method. the colours and solubility of l-lps were improved. when the leptospiral cells were stored for a long period of time, and treated by edta-na, the phase distribution of the lps changed, i.e. they returned from water phase into phenol phase. such change was related to the quantity of both the saccharide and lipid.19892511666
relationship among selected leptospira interrogans serogroups as determined by nucleic acid hybridization.leptospiral dnas from a variety of leptospira interrogans serogroups of veterinary significance, as well as a nonpathogenic leptospira, were compared by southern blot hybridization of ecori-digested genomic dna. the serogroups examined could be assigned to one of three groups on the basis of the degree of cross-hybridization between genomic dnas. only a few restriction fragments hybridized between the three groups, and most of these were shown to contain ribosomal dna. the restriction fragment l ...19892574185
detection of leptospires in urine by polymerase chain reaction.primers for polymerase chain reaction (pcr) were synthesized from clones derived from a leptospira hardjo (type hardjobovis) library. one pair of synthetic oligonucleotide primers was selected for further analysis. under experimental conditions an amplification was obtained with dna of leptospira interrogans of some serovars belonging to serogroup sejroe. however, very little or no amplification was observed with dna from other serovars of this group. no amplification was observed with dna from ...19892584377
[endocytosis and cytotoxin effect induced by the attachment of the glycolipoprotein of leptospires to vascular endothelial cell in culture].the glycolipoprotein (glp) of various virulent leptospires was extracted, purified and identified. the glp was combined with fluorescence rhodamine b and the colloidal gold as the probe. meanwhile, the bovine aortic endothelial cell (en) was isolated and cultured in the medium 199 "nissui". the glp-rhodamine b and glp-colloidal gold probe were added to cultured en and incubated at 4 degrees c for 2 h then at 37 degrees c for 2 h. the interaction between glp-rhodamine b, glp-cg probe and en were ...19892591917
central nervous system leptospirosis in the philippines.one hundred hospitalized patients in manila, philippines with aseptic meningoencephalitis were screened for leptospirosis. on the basis of a microscopic agglutination titer of 1:1,600 or greater, the diagnosis was made in five cases, yet in no instance had leptospirosis been included in the differential diagnosis on admission to the hospital. four of the five patients first noted neurologic symptoms during the second week of illness; two patients presented with encephalitis, two with meningitis ...19892609216
effect of vaccination with a pentavalent leptospiral vaccine containing leptospira interrogans serovar hardjo type hardjo-bovis on type hardjo-bovis infection of cattle.effectiveness of 2 pentavalent leptospiral vaccines containing leptospira interrogans serovar hardjo was evaluated for protection of steers from infection with serovar hardjo type hardjo-bovis. the hardjo component of 1 vaccine was prepared from serovar hardjo type hardjoprajitno. the hardjo component of the other vaccine was prepared from serovar hardjo type hardjo-bovis. two steers were vaccinated once and 4 steers were vaccinated twice with the pentavalent vaccine containing type hardjoprajit ...19892610425
skin reaction to lipids from avirulent strain shibaura of leptospira interrogans serovar copenhageni.sonically disrupted cells from avirulent strain shibaura of leptospira interrogans serovar copenhageni induced a skin reaction characterized by infiltration of polymorphonuclear leukocytes (pmn) associated with some edema in guinea pigs. to determine the substance inducing infiltration of pmn, lipids of avirulent strain shibaura were extracted with chloroform--methanol--water after washing with acetone. the lipids comprised 28% of the dry weight of the cell. when the lipids were further separate ...19892611731
[glycoproteins from leptospira interrogans serogroup icterohaemorrhagiae: distribution in the liver and kidney of experimentally infected guinea pigs].tissue damage in leptospirosis has been ascribed to direct effect of the microorganisms and/or their virulence, including products synthetized by leptospires or released during their lysis. this study aimed at chemical extraction of the glycolipoprotein (glp) from virulent leptospires, production of a rabbit anti-glp and analysis of its distribution in liver and kidney of inoculated guinea-pigs, sacrificed sequentially from the 1st to 6th day of infection, covering the whole, spectrum of acute l ...19892626644
first human isolate of leptospira interrogans as serovar bratislava in italy.a strain of leptospira interrogans was isolated from a patient suffering from leptospirosis and was typed by the cross agglutination absorption test using monoclonal antibodies prepared against different serovars of the australis serogroup. this newly isolated strain belonged to serovar bratislava. it is the first reported isolation from man, in italy, of leptospira bratislava, thus supporting the emerging role of this serovar in human leptospirosis.19892627502
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
evidence for sheep as a maintenance host for leptospira interrogans serovar hardjo. 19892922905
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
nucleic acid probe characterizes leptospira interrogans serovars by restriction fragment length polymorphisms.restriction endonuclease analysis (rea) of genomic dna can discriminate between many leptospira interrogans serovars. however, several serovars have similar restriction endonuclease digestion patterns which prohibits accurate identification. this investigation expands previous rea studies of l. interrogans to include serovars in serogroup tarassovi. most serovars in this serogroup had characteristic digestion patterns by which they could be identified. however, four of the serovars in this serog ...19901979703
the detection of genetic variation in leptospira interrogans serogroup icterohaemorrhagiae by ribosomal rna gene restriction fragment patterns.deoxyribonucleic acid from leptospira interrogans serogroup icterohaemorrhagiae reference strains together with clinical and animal isolates were cleaved with ecori, electrophoresed and transferred to nylon membranes. an escherichia coli mre 600, 16s + 23s ribosomal rna template was used in the synthesis of a single strand biotin-labelled cdna probe using a reverse transcriptase. ribosomal rna cistrons present in the dna fragments of strains were located using the cdna probe. between 4 and 7 wel ...19901982104
cloning of genes for a hemolytic factor of leptospira interrogans serovar autumnalis strain congo 21-543.a dna fragment encoding a hemolytic factor was cloned from the parasitic spirochete leptospira interrogans serovar autumnalis strain congo 21-543. initial clones were isolated by screening a genomic library in pbr322 in escherichia coli for hemolytic activity. hemolytic activity was coded by a 4.5 kilobase bamhi-hindiii fragment. southern hybridization with dnas from other strains of leptospira using this gene as a probe showed that dnas from non-parasitic strains failed to hybridize with the pr ...19902077368
the effect of storage time on isolation of leptospira interrogans from bovine kidneys.kidney tissues from 20 cattle infected with leptospira interrogans serovars hardjo, pomona, or grippotyphosa were cultured on the day of slaughter and 3, 6, and 8 days later to examine the effect of storage time on the recovery of leptospires by conventional culture methods. leptospires were isolated from 85% of infected bovine kidney tissues cultured on day 1, and from 95%, 90%, and 90% of kidney tissues stored in transport medium at 4 c for 3, 6, and 8 days, respectively, prior to inoculation ...19902090270
first isolation of bacteriophages for a spirochaete: potential genetic tools for leptospira.three bacteriophages of the saprophytic aquicole bacterium leptospira biflexa were isolated from sewage waters from the outskirts of paris, france. these phages do not infect representative strains of the pathogenic species leptospira interrogans, and their host range is restricted to serovar patoc of the saprophytic species. the phages were found to be lytic and no lysogenic state could be demonstrated. electron micrographs showed that the phages were morphologically identical and had polyhedra ...19902092364
[detection of the microquantity dna of leptospira interrogans by polymerase chain reaction].leptospirosis is a severe zoonosis in the world. the methods for detecting leptospira are not sensitive and specific so far. the problems in early diagnosis and epidemiological identification of leptospirosis remain unsolved. two recombinant dna fragments of serogroup icterohaemorrhagiae, leptospira were selected by repeated molecular cloning and screening in this study firstly. one of them can hybridize with the dna of various serogroups of leptospira interrogans; the other can only hybridize w ...19902093056
the effect of heat-inactivation on agglutinating antibody titers to leptospira interrogans. 19902094439
porcine leptospirosis in iowa.the epidemiology of leptospirosis in iowa swine was examined on the basis of serologic results and herd data from 55 herds in the national animal health monitoring system (nahms) program and culture results and histories from 578 cases of reproductive failure submitted to the iowa veterinary diagnostic laboratory during a 3-year period. thirty-eight percent of sera from nahms herds contained antibodies against 1 or more of 12 leptospira antigens. leptospires were isolated from 9 (1.6%) of 578 ca ...19902094443
evaluation of an enzyme immunoassay for diagnosis of bovine leptospirosis caused by leptospira interrogans serovar hardjo type hardjo-bovis.sensitivity and specificity of 4 different antigen preparations from leptospira interrogans serovar hardjo were compared in an enzyme immunoassay for detection of antibodies against serovar hardjo type hardjo-bovis in serum. two antigens prepared using detergents showed serogroup cross-reactivity. a mechanically extracted membrane and a lipopolysaccharide antigen showed a high degree of leptospiral serogroup specificity. the lipopolysaccharide antigen was the most suitable antigen for detection ...19902095282
[immunodiagnosis of human leptospirosis by elisa-igm, employing different antigenic preparations from prevalent serovars of leptospira interrogans].a comparative study among different serovars of leptospira interrogans was performed in order to prepare antigens to detect igm antibodies by elisa in early and late phase of human leptospirosis. ten serovars were chosen among the most prevalent detected by microscopic seroagglutination (sam) in são paulo city. using elisa-igm five of them showed better results (canicola, hebdomadis, icterohaemorrhagiae, cynopteri and brasiliensis). these ones were also studied in a pool. the non-treated antigen ...19902101517
zoonotic infections in northern ireland farmers.evidence of past zoonotic infection was investigated serologically in randomly selected northern ireland farmers. the percentage of farmers with antibody was: brucella abortus (0.7), leptospira interrogans serovars (8.1), borrelia burgdorferi (14.3), toxoplasma gondii (73.5), coxiella burnetii (28.0), chlamydia psittaci (11.1) and hantavirus (1.2). the results show that northern ireland farmers have been exposed in the past to zoonotic infections. it is not known if these infections contributed ...19902123457
[high resolution light microscopy: adaptation of the method and its use in the study of experimental leptospirosis in guinea pigs].morphological lesions in parenchimal and mesenchimal structures of liver and kidney were studied in guinea-pigs experimentally infected with leptospira interrogans serogroup icterohaemorrhagiae in comparison with a group of non-infected guinea-pigs. all specimens were submitted to conventional light microscopy as well as to high resolution light microscopy, in one micrometer sections of tissue embedded in glycolmethacrylate. high resolution light microscopy, applied for the first time in leptosp ...19902135358
molecular analysis of a sphingomyelinase c gene from leptospira interrogans serovar hardjo.a thermolabile hemolysin from leptospira interrogans serovar hardjo, strain sponselee, was shown to specifically degrade sphingomyelin. nucleotide sequence determination revealed that sphingomyelinase activity was encoded by an open reading frame of 1,668 nucleotides. although a putative signal sequence could be identified, no evidence for protein export in either l. interrogans or escherichia coli was obtained. the apparent molecular mass of the expression product in e. coli minicells was 41.2 ...19902163985
protective activity of glycolipid antigen against infection by leptospira interrogans serovar canicola.a protective glycolipid antigen (pag) was extracted from leptospira interrogans serovar canicola with chloroform/methanol/water (1:2:0.8, by vol.) and partially purified by silica gel column chromatography. the pag elicited a protective response in hamsters and in cyclophosphamide-treated mice subsequently challenged with homologous leptospira. the pag band was detected as a single smear-like band, corresponding to a protein of 23-30 kda, by silver-staining in sds-page. in immunoblots, this band ...19902182771
isolation of leptospira interrogans serovar bratislava from stillborn and weak pigs in iowa.leptospira interrogans serovar bratislava was isolated from a herd of swine in iowa with a history of stillborn and weak neonatal pigs. placentas, kidneys, and lungs of stillborn and weak pigs from 3 litters were processed to detect leptospires by use of bacteriologic culture and fluorescent antibody testing. sera from stillborn and weak pigs were tested to detect agglutinating antibody against leptospires. a low antibody titer against l interrogans serovar bratislava was detected in the sera of ...19902189848
cloning of genes required for amino acid biosynthesis from leptospira interrogans serovar icterohaemorrhagiae.leptospira interrogans belongs to a large family of important pathogens, which is part of the order spirochaetales, a distinct group of eubacteria. in order to obtain a better understanding of the genetic organization of this species, we have constructed a dna library of the serovar icterohaemorrhagiae, using the escherichia coli vector puc13. we have isolated leptospira dna fragments containing the genetic information required to complement strains of e. coli with defects in proline and leucine ...19902204676
susceptibility of mongolian gerbils (meriones unguiculatus) to leptospires and the protective effect of vaccination.mongolian gerbils, meriones unguiculatus, were shown to be highly susceptible to leptospira interrogans serovars such as icterohaemorrhagiae, copenhageni, canicola, autumnalis, javanica, pyrogenes and hebdomadis as compared to guinea pigs and hamsters. mortality with signs of haemorrhage and jaundice was recorded in all experimental rodents after intraperitoneal inoculation with all strains of the serovars indicated. however, mongolian gerbils were comparatively susceptible to strains which were ...19902219666
serum agglutinating antibodies to leptospira interrogans serovar canicola presumed due to serovar robinsoni infection in an australian dog. 19902222370
leptospira interrogans serovar unipertama isolated in malaysia.a leptospiral isolate from a bovine kidney was found to be antigenically different from all previously recognized serovars of leptospira interrogans based on the cross-agglutinin absorption test. the new serovar belongs to the sejroe serogroup, and the name leptospira interrogans serovar unipertama is proposed for it, with strain k2-1 as the reference strain.19902223603
evaluation of monoclonal antibody f9-4 as immunological probe for leptospira interrogans.i assayed the lack of reactivity of monoclonal antibody (mab) f9-4 with nonpathogenic leptospires. of 47 saprophytic strains tested, 46 did not react in an enzyme immunoassay and 1 was recognized by mab f9-4, as usually reported with pathogenic leptospira strains. on the other hand, the mab did not react with one pathogenic strain, thus showing that the ability of mab f9-4 to discriminate between pathogenic and nonpathogenic leptospires is not absolute.19902229401
species differentiation of leptospira interrogans serovar hardjo strain hardjobovis from strain hardjoprajitno by dna slot blot hybridisation.slot blot hybridisation studies with total genomic dna probes were used to compare leptospira interrogans serovar hardjo strain hardjoprajitno, strain hardjobovis and a number of other leptospira interrogans serovars. strains hardjoprajitno and hardjobovis were found to have little genetic relationship with each other when compared to some of the other serovars tested. hardjoprajitno is closely related to serovar icterohaemorrhagiae and not to hardjobovis whereas hardjobovis is closely related t ...19902236916
vaccination of mice with lipopolysaccharide (lps) and lps-derived immuno-conjugates from leptospira interrogans.mice were vaccinated with lipopolysaccharide (lps) from leptospira interrogans serovar pomona or hardjo, or with the polysaccharide (ps) fraction of the lps, or with an immunoconjugate of ps and diphtheria toxoid (dt). maximum agglutinin titres were found 6-10 weeks after vaccination with lps or ps-dt conjugate; the latter elicited antibody titres at least 10 times higher than those produced in response to lps. animals failed to react significantly to ps. titres elicited by antigens of serovar p ...19902250290
antigens recognized by the human immune response to vaccination with a bivalent hardjo/pomona leptospiral vaccine.serum from volunteer subjects vaccinated with a bivalent whole cell vaccine of leptospira interrogans serovar hardjo/serovar pomona grown in protein-free medium, was tested by the microscopic agglutination test (mat), enzyme-immunoassay (eia) and immunoblotting. specific igm antibodies to either serovars hardjo or pomona were detected in some subjects as early as 6 days after vaccination with peak antibody levels occurring 13-68 days after vaccination. whereas all subjects produced specific igm ...19902257162
biological activities and endotoxic activities of protective antigens (pags) of leptospira interrogans.the biological and endotoxic activities of protective antigens (pags) prepared by the chloroform-methanol-water method from leptospira interrogans serovars lai, copenhageni and canicola were examined. the pag preparations did not show a local shwartzman reaction in the rabbits at doses of 100 micrograms and 50 micrograms/site and lethal toxicity to galactosamine-sensitized mice at the dose of 12.5 micrograms to 50 micrograms/mouse. pags exhibited a weak cytotoxic action on peritoneal exudate mac ...19902261063
biological effects of leptospiral lipopolysaccharide to mouse b, t and nk cells.leptospiral lipopolysaccharides (lpss) extracted from leptospira interrogans serovars copenhageni and hebdomadis were tested for the biological effect to mouse b, t and nk cells. each leptospiral lps was a potent mitogen for spleen b cells. activation of the cells was also expressed by polyclonal b cell activation. in contrast, mitogenicity for t cells, induction of interleukin-2 (il-2) secretion in t cells and increase of tumor-killing activity and chemiluminescence in nk cells were not observe ...19902280502
purification and characterization of a protein antigen from leptospira interrogans serovar hardjo, common to a wide range of bacteria.a protein with a molecular mass of 64 kda (p64) from leptospira interrogans serovar hardjo was partially purified by using successively, phase partitioning with triton x-114, ion-exchange chromatography and sucrose gradient centrifugation. purification to homogeneity was obtained by electroelution of p64 from sds-polyacrylamide gels. monospecific rabbit antiserum (r alpha p64) was prepared using the purified protein preparation. p64 had a native molecular mass of greater than 670 kda and was rec ...19902283504
evaluation of an elisa for the diagnosis of experimentally induced and naturally occurring leptospira hardjo infections in cattle.an enzyme-linked immunosorbent assay (elisa) for the diagnosis of leptospira interrogans serovar hardjo (hardjo) infection in cattle was compared with the microscopic agglutination test (mat). glutardialdehyde was used in the elisa to couple sonicated hardjo antigen to the microtiter plate. mouse monoclonal anti-bovine igg1 coupled to peroxidase was used as conjugate. sera from calves experimentally inoculated with hardjo reacted positively in the mat as early as 10 days after inoculation; these ...19902305547
in vitro association of leptospires with host cells.interactions of leptospira interrogans with cultured endothelial and kidney epithelial cells were assayed by examining (i) cytoadherence of intrinsically radiolabeled leptospires to eucaryotic cell monolayers and (ii) penetration of leptospires through cell monolayers grown on polycarbonate filters in chemotaxis chambers. l. interrogans serovars attached to cultured cells in a dose- and time-dependent manner. adherence was diminished following pretreatment of organisms with proteases, rabbit imm ...19902307512
nucleotide sequence of a 16s rrna gene for leptospira interrogans serovar canicola strain moulton. 19902326171
immunological reactivity and passive protective activity of monoclonal antibodies against protective antigen (pag) of leptospira interrogans serovar lai.monoclonal antibody (mab) ag1 against the protective antigen (pag) was produced and characterized. it had been extracted from leptospira interrogans serovar lai by the chloroform-methanol-water method and was of glycolipid nature (23-30kd). the fact that the pag was a serogroup-specific antigen was shown by mab ag1, because mab ag1 agglutinated serovars of serogroup icterohaemorrhagiae. purified mab lw2 and lw3 which are agglutinating antibodies of serovar lai and ag1 passively protected hamster ...19902331299
heat stability of protective antigen of leptospira interrogans serovar lai.protective antigen (pag; glycolipid antigen; molecular size, 23 to 30 kilodaltons), the serogroup-specific antigen partially purified from leptospiral cells, is one of the most important protective antigens. the heat stability of pag was compared with that of whole-cell (wc) antigen by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting, protective activity, opsonin-inducing activity, agglutinating antibody-inducing activity, and an inhibition test in an enzyme-linked ...19902332463
isolation and characterization of the 5s rrna gene of leptospira interrogans.the gene encoding the 5s rrna for leptospira interrogans serovar canicola strain moulton was isolated and sequenced. the 5s rrna gene occurs as a single copy within the genome and encodes a 117-nucleotide-long rna molecule. the 5s rrna gene is flanked at both the 5' and 3' ends by regions of a + t-rich sequences, and the 5'-flanking region contains a promoter sequence. l. interrogans has a unique and remarkable organization of the 5s rrna gene. the 5s rrna molecule exhibits a strong similarity t ...19902345145
unique ribosome structure of leptospira interrogans is composed of four rrna components.all known ribosomes of procaryotic organisms are made up of three rrna components that are 23, 16, and 5s in size. we now report that in some leptospira interrogans strains, the classical 23s rrna is further processed to generate 14 and 17s rrnas. this processing step was previously known to occur only in some eucaryotes and in a small group of procaryotes. the implications of this finding are discussed.19902345155
serologic analyses of cottontail rabbits for antibodies to borrelia burgdorferi.an enzyme-linked immunosorbent assay was developed to detect antibodies to borrelia burgdorferi in cottontail rabbits captured in millbrook, n.y., and new york, n.y. five antigenically variable strains of b. burgdorferi were analyzed to determine the variability of serologic test results. in analyses of 79 serum samples, seropositivity ranged from 56% for a strain cultured from kidney tissues of a cottontail rabbit to 68% for a strain isolated from a larva of ixodes dentatus, a tick that parasit ...19902351732
isolation of leptospira interrogans serovar mozdok from aborted swine fetuses in portugal. 19902382358
[study on the characteristics of agglutination reaction of mcab with leptospira interrogans outer envelope].three mcab were produced against an outer envelope preparation from leptospira, interrogans, serovar lai by fusion of sp2/0 myeloma cells with immune balb/c mice spleen cells. the fusion rate was 96% and the antibody positive rate was 50%. one of the hybridomas, e4b11c9, reacted with 13 of the 13 serovars of the icterohaemorrhagiae serogroup in microscopic agglutination test (mat) but did not react with the 18 representative serovars of l. interrogans and l. biflexa serovar patoc and leptonema i ...19902391093
the use of immunodeficient male (cba/n x balb/c) f1 mice to produce monoclonal antibodies directed to proteins of leptospira interrogans rather than to immunodominant lipopolysaccharides.a method, using an immunodeficient mouse strain, for the production of monoclonal antibodies directed exclusively against the proteins in an antigen mixture also containing immunodominant lps, is described. male (cba/n x balb/c) f1 mice were immunized with an outer envelope antigen mixture from leptospira interrogans strain wijnberg containing both lipopolysaccharides and proteins. the immune response in these mice was shown to be predominantly directed against protein antigens. hybridoma cell l ...19901694817
macrophage activation by leptospiral lipopolysaccharide.leptospiral lipopolysaccharides (lpss) extracted from leptospira interrogans serovars copenhageni and hebdomadis were tested for the ability to induce macrophage activation. in-vitro analysis showed that each leptospiral lps was a potent activator to macrophages. after stimulation with the lpss, interleukin-1 (il-1) secretion, interferon (ifn) production and chemiluminescence (cl) response were induced. intravenous high-dose injection of the leptospiral lpss induced various lesions such as necro ...19901698063
[study on the production, identification of serogroup-specific monoclonal antibodies against leptospires of australis serogroup and detection of its antigen].spleen cells of balb/c mice immunized with whole leptospira interrogans serogroup australis serovar australis strain 620 were fused with myeloma cells line sp2/0. specificities of four mcabs determined by mat. 2e1 mcab (igg3) reacted with 11 serovars, of the australis serogroup, but did not react with 22 representative serovars of l. interrogans in 20 serogroups, l. biflexa strain patoc i and leptonema illini strain 3055. 2e1 mcab showed serogroup specificity for australis by agglutination and t ...19901709413
serological reactions against leptospira interrogans serovars in new zealand horses. 199016031597
leptospirosis in chonbuk province of korea in 1987.leptospirosis is a zoonosis with protean clinical manifestations. its diagnosis requires a high index of suspicion and is confirmed by isolation of the organism or, more commonly, by serologic tests. in the fall of 1987, after severe flooding, we saw 93 patients with leptospirosis, confirmed by a microagglutination test. thirteen percent of the patients had no clinical or laboratory findings except fever and headache, but the rest had mild to severe manifestations. jaundice, renal failure, and a ...19902271509
serological reactions against leptospira interrogans serovars in alpacas after vaccination. 199116031613
serological studies on leptospira strain ictero no. i using monoclonal antibodies.in order to elucidate the full serological characteristics of strain ictero no. i, the first strain of leptospira isolated by inada and ido in 1914, 17 monoclonal antibodies against the strain were produced by cell fusion technology. the antibody-producing hybridomas were designated imas 1 to 17. the reactivities of the monoclonal antibodies produced by the hybridomas were determined by the microscopic agglutination test. one of the 17 monoclonal antibodies, ima 1, reacted with strains ictero no ...19911714535
cloning, characterization and taxonomic significance of genes for the 5s ribosomal rna of leptonema illini strain 3055.the genes encoding the 5s ribosomal rna (rrna) for leptonema illini strain 3055 were isolated and sequenced. the 5s rna molecule encoded was 117 nucleotides long. the genome of strain 3055 contained two genes for 5s rrna that were located close together. the nucleotide sequences of the leptonema illini genes exhibited less similarity to the rrna gene of leptospira interrogans strain moulton and also to those of typical eubacterial genes than did the rrna genes of other leptospires. however, the ...19911720165
use of the enzyme linked immunosorbent assay (elisa) to detect the igm and igg antibody response to leptospira interrogans serovar hardjo in pregnant ewes.fourteen pregnant ewes were inoculated with leptospira interrogans serovar hardjo via intramuscular injection or inoculation via the conjunctiva. the serological response to inoculation detected by the microscopic agglutination test was compared to igm and igg antibody levels detected by enzyme linked immunosorbent assay. intramuscular injection produced a better serological response than conjunctival inoculation. the mean igm response was short lived whereas the igg antibody response and the ma ...19911741914
leptospires isolated from toads and frogs on the island of barbados.four pathogenic strains of leptospires were isolated from the kidneys of toads (bufo marinus) and seven from frogs (eleutherodactylus johnstonei). isolates from two toads and one frog belonged to serovar bim, the causative agent of most cases of severe leptospirosis on barbados. the other eight strains belonged to a new serovar within the australis serogroup. the name bajan is proposed for this new serovar of leptospira interrogans.19911741925
sample preparation method for polymerase chain reaction-based semiquantitative detection of leptospira interrogans serovar hardjo subtype hardjobovis in bovine urine.an improved method of preparing bovine urine samples was developed for the rapid, specific, and sensitive detection of leptospira interrogans serovar hardjo (subtype hardjobovis) dna by the polymerase chain reaction (pcr). a total of 100 leptospire-free cows, 4 experimentally infected cows, and 2 negative control cows were used. pcr results were improved by (i) using 10-ml urine samples instead of 1-ml samples, (ii) adding 10(7) to 10(8) leptospira biflexa serovar patoc cells as a carrier to eac ...19911757552
gold immunoblot analysis of igm-specific antibody in the diagnosis of human leptospirosis.an immunoblot for the detection of leptospirosis was developed in our laboratory. antigen prepared from leptospira interrogans serovar bataviae was dotted onto nitrocellulose paper and blocked with skim milk. test and control sera diluted 1:20 were applied to the dot, incubated, and washed. anti-human igm colloidal gold conjugate was added and the dots were washed. a positive reaction was shown by the development of a pink dot against a white background. the test was performed on 62 sera that te ...19911763792
effect of vaccination with a monovalent leptospira interrogans serovar hardjo type hardjo-bovis vaccine on type hardjo-bovis infection of cattle.effectiveness of 2 concentrations of a monovalent vaccine containing leptospira interrogans serovar hardjo type hardjo-bovis was evaluated for protection of heifers from infection with type hardjo-bovis. nine heifers were given 2 doses of low-dose vaccine (8.32 x 10(8) cells/dose); 9 heifers were given 2 doses of high-dose vaccine (8.32 x 10(9) cells/dose); and 1 steer and 1 heifer were maintained as nonvaccinated controls. groups of vaccinated cattle were challenge-exposed with serovar hardjo t ...19911767985
lipids and fatty acids of leptospira interrogans serovar copenhageni virulent strain shibaura.lipids and fatty acids of leptospira interrogans serovar copenhageni virulent strain shibaura were analyzed by thin-layer chromatography, gas-liquid chromatography, gas-mass spectrometry and infrared absorption spectrometry. the virulent cells possessed a characteristic lipid pattern consisting of free fatty acid (ffa) (41.8%), one major unidentified phospholipid (14.8%), phosphatidylethanolamine (pe) (12.9%), cholesteryl ester (ce) (9.3%), lysophosphatidylethanolamine (lpe) (4.9%) and diphospha ...19911784083
survey to estimate prevalence of leptospira interrogans infection in mature cattle in the united states.a total of 5,142 kidney tissue samples and 5,111 serum samples from mature cattle in 49 states and puerto rico were collected at slaughter. age of cattle ranged from 1 to 16 years (mean, 6.6 years). leptospires were isolated from 88 (1.7%) kidney tissues, and 2,493 (49%) sera contained antibodies against 1 or more of 12 leptospira interrogans serovars. leptospires were observed by immunofluorescence in 41 (0.8%) kidney tissues. using agglutinin-absorption tests, 73 (83%) isolates were identified ...19911785719
relationships between prevalence of leptospira interrogans in cattle, and regional, climatic, and seasonal factors.on the basis of serologic test results and isolation of leptospires from mature cattle, distribution and prevalence of leptospira interrogans serovars and genotypes were compared by state and region of the united states. relationships between isolation rate and month of sample collection, mean regional temperature, and mean regional precipitation were examined. isolation rate and seroprevalence were significantly (p less than 0.001) higher for southeastern, south central, and pacific coastal reg ...19911785720
leptospira interrogans serovar canicola: a causal agent of sow abortions in arequipa, peru.an outbreak of abortions, stillbirths, mummified piglets and neonatal deaths in a pig herd in arequipa, peru is described. a total of 31 of 240 sows aborted between may and september 1988. when sera were examined 12 of 14 had very high titres of antibody to canicola pc125 and canicola hond utrecht, but there were also high titres of antibody to other leptospiral serovars. a detailed investigation was made and serovar canicola pc125 was isolated from the urine of four sows which had aborted and t ...19911796527
leptospira interrogans serovar bratislava infection. 19911800472
isolation and characterization of partially purified leptospiral antigens.the methanol extract of leptospira interrogans serovar canicola was purified by precipitation with acetone or acetone and chloroform. the antigenicity of the antigen was not altered by heating or treatment with pepsin and pronase. however the antigenicity was lost when the antigen was treated with periodic acid. chemical analysis revealed the presence of 40% carbohydrate (22% methylpentose, 28% hexoses), 4% protein, 20% lipid and 2.7% phosphate. the complement fixation test with sera from patien ...19911844967
characterization of borrelia coriaceae antigens with monoclonal antibodies.three monoclonal antibodies (f6f3, f6b11, and f6b3) were developed against borrelia coriaceae antigens. all three antibodies appeared to be specific for this species and did not cross-react with borrelia burgdorferi (strains b31 and irs), borrelia hermsii, borrelia anserina, leptospira interrogans serovar hardjo, or treponema hyodysenteriae, as determined by indirect fluorescent antibody staining, enzyme-linked immunosorbent assay, and western immunoblot analysis. only one of these antibodies, f ...19911855995
comparison of protective effects with tetra-valent glycolipid antigens and whole cell-inactivated vaccine in experimental infection of leptospira.the protective antigens (pags), glycolipid substance, were extracted from leptospira interrogans serovars autumnalis, hebdomadis, australis and copenhageni, which were considered as main causal serovars of human leptospirosis in japan, with chloroform-methanol-water (1:2:0.8, [vol/vol/vol]) solution. the tetra-valent formalin-inactivated leptospiral vaccine (weil's disease and akiyami combined vaccine) composed of the four serovars mentioned are used as vaccine to protect human from leptospiral ...19911870437
antigens recognized by the human immune response to severe leptospirosis in barbados.serum samples obtained from patients hospitalized in barbados with severe leptospirosis were tested by the microscopic agglutination test (mat), enzyme immunoassay (eia) and immunoblotting with leptospires that had been isolated from these patients. while serum samples taken a few days after onset of symptoms often showed no apparent correlation between mat and eia, later sequential serum samples produced similar profiles in both tests during the course of infection. immunoblotting sonicate from ...19911879481
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