Publications

effects of products of autolysis of tissue and urine on the viability, morphology, and antigenicity of leptospira interrogans serovar pomona.	the effect of the products of autolysis on leptospira interrogans serovar pomona was investigated in bovine kidney tissues and urine inoculated with this organism. no viable leptospires were found at 24 h or subsequently after inoculation of kidney tissues or urine. leptospires and their soluble antigens were rapidly destroyed in tissues stored at 20 degrees c and could not be detected by the fluorescent-antibody test and the enzyme-linked immunosorbent assay. on the other hand, leptospires were ...	1985	3882747
enzymatic radioimmunoassay for detecting leptospira interrogans serovar pomona in the urine of experimentally-infected pigs.	an enzymatic radioimmunoassay (eria) has been developed for detecting leptospira interrogans serovar pomona in porcine urine. four grower pigs were experimentally infected with serovar pomona. a total of 39 urine samples was collected, and eria was compared with dark ground microscopy (dgm) and culture for demonstrating leptospiruria. of 20 samples positive by at least one technique, leptospires were detected by eria in 14, by culture in 16 and by dgm in 13. eria, unlike the other 2 methods, was ...	1985	3890354
monoclonal antibodies to leptospira interrogans serovar pomona.	three monoclonal antibodies produced against leptospira interrogans serovar pomona have been studied for their diagnostic usefulness. all three monoclonals reacted strongly in the enzyme-linked immunosorbent assay and indirect fluorescent antibody test with serovar pomona and did not react with serovars grippotyphosa, canicola, icterohaemorrhagiae and hardjo.	1985	3893661
isolation of a spirochete from the soft tick, ornithodoros coriaceus: a possible agent of epizootic bovine abortion.	a borrelia-like spirochete was detected in all three parasitic stages of ornithodoros coriaceus, the soft tick implicated in the epizoology of epizootic bovine abortion. after the spirochete had been isolated, its distinctness from other north american tick-borne borreliae as well as from spirochaeta aurantia, treponema pallidum, and leptospira interrogans serovar pomona was established on the basis of its morphology, protein components, and inability to infect mice. the spirochete is passed tra ...	1985	3898367
serological interrelationship of leptospira serovar and genus-specific antigens by enzyme-linked immunosorbent assay.	the serological interrelationship of a sonicated antigen (pom-s) and an alkali-extracted "fraction 4" antigen (pom-f4) from leptospira interrogans serovar pomona, and an ethanol-precipitated (pat-e) and a formolized, sonicated antigen (pat-f) from leptospira biflexa serovar patoc were investigated. the serological responses of rabbits immunized with these antigens were examined by the enzyme-linked immunosorbent assay (elisa), the microscopic agglutination test, and the 2-mercaptoethanol microsc ...	1984	6084016
leptospirosis associated with serovars hardjo and pomona in red deer calves (cervus elaphus).	four red deer calves (cervus elaphus) died with severe nephritis apparently associated with infection by leptospira interrogans serovar pomona. the sera of 12 in-contact red deer calves were examined for leptospiral agglutinins and nine showed titres to pomona consistent with recent infection. two also showed titres of 1:100 to serovar hardjo. the urine of five of these in-contact calves was examined periodically over a period of nine months. all were initially leptospiruric, four being infected ...	1984	16031052
a serological study of bovine leptospirosis in the district of taranaki.	a cross-sectional serological survey of dairy cattle in taranaki in 1979-80 indicated that 62% (551/891) of the animals had evidence of leptospira interrogans serovar hardjo infection as disclosed by the microscopic agglutination test. titres to leptospira interrogans serovar pomona were demonstrated in only 4% (23/591) of the animals examined. the high prevalence of hardjo infection is suggestive of an endemic infection whilst the low level to pomona is indicative of sporadic infection. in a de ...	1984	16031079
the immunoglobulin response of swine following experimental infection with leptospira interrogans serovar pomona.	the antibody response of pigs following experimental infection with leptospira interrogans serovar pomona was examined using enzyme immunoassay (eia) and the microscopic agglutination test (mat). leptospires elicited the production of both igm and igg classes of antibody, with igg levels persisting for much longer than igm. a comparison of mat and eia indicated that the detection of specific igm by eia was potentially useful in distinguishing between past and recent infection in pigs. agglutinin ...	1984	6741345
a pomona serogroup-specific, agglutinating antigen in leptospira, identified by monoclonal antibodies.	monoclonal antibodies were produced by hybridoma cell lines derived by fusion of mouse ns-1 myeloma cells with splenocytes from mice immunized with leptospira interrogans serovar pomona. one hybridoma (a3) produced an igg2a antibody which agglutinated all leptospires of the pomona serogroup but not leptospires representative of serovars of any other serogroup. the antibody precipitated in immunodiffusions with either alkali- or phenol-extracted lipopolysaccharide and also with the tm antigen of ...	1983	6417619
species- and genus-specific antigens in leptospira, revealed by monoclonal antibodies and enzyme immunoassay.	mouse antisera to leptospira interrogans serovar pomona or l. biflexa serovar patoc agglutinated homologous leptospires but not leptospires of serovars from any heterologous serogroup tested. when tested by enzyme immunoassay (eia), pomona and patoc antisera reacted with all serovars tested from l. interrogans, l. biflexa or l. illini species. a non-agglutinating hybridoma-derived monoclonal antibody reacted by eia only with serovars of the pathogenic l. interrogans species but not with l. bifle ...	1983	6359778
the first isolation of leptospira interrogans serovar pomona from cattle in botswana.	serological evidence for the occurrence of l. pomona associated with abortions in cattle was supported by the successful isolation of the organism from the urine of a cow. leptospirosis should be considered as a possible cause of abortion even in relatively dry regions.	1983	6631909
evaluation of a hardjo-pomona vaccine to prevent leptospiruria in cattle exposed to a natural challenge with leptospira interrogans serovar hardjo.	the efficacy of a vaccine against leptospira interrogans serovar pomona and leptospira interrogans serovar hardjo was evaluated in a group of dairy heifers that were serologically negative at the time of vaccination and later subjected to natural challenge with l. interogans serovar hardjo. thirty-nine heifers were vaccinated twice, at a one-month interval, with a commercially prepared bivalent vaccine, while 43 unvaccinated heifers were used as controls. after vaccination, microscopic agglutina ...	1982	7115235
leptospira interrogans serovar pomona associated with abortion in cattle: isolation methods and laboratory animal histopathology.	leptospira interrogans serovar pomona was successfully isolated from cattle urine in the western transvaal after an abortion storm had occurred. direct inoculation of emjh medium proved the most successful method. the selective agent, 5-fluorouracil, was most effective in controlling contamination when used at the 0,4 mg/ml level. the strain isolated was pathogenic in hamsters, but specific lesions and the leptospirae were seen only where overwhelming infection occurred.	1982	7122066
evidence that leptospiral lipopolysaccharide is not an important protective antigen.	cba/n mice, which could not produce antibodies against lipopolysaccharide (lps) from either escherichia coli or leptospira interrogans serovar pomona, produced levels of agglutinating antibodies against leptospires similar to those produced by immunologically normal cba mice. cba/n mice were thus resistant to acute leptospiral infection and cba/n immune serum passively protected immunosuppressed mice from infection. the results suggest that antibodies against lps are not important in protection ...	1982	7143431
presence of vi antigen in a virulent strain of leptospira interrogans serovar pomona and relation of vi antigens of leptospiras to resistance to leptospiricidal activity mediated by antiserum plus complement.	vi antigen was found in a virulent strain of leptospira interrogans serovar pomona. the presence of vi antigen was shown by the agglutinin-absorption and precipitin-absorption tests. each strain of pomona and copenhageni which possessed vi antigen and was resistant to the leptospiricidal activity mediated by the antiserum plus complement lost vi antigen and became susceptible to the leptospiricidal activity when cultured in the presence of 8-azaguanine. the strains thus treated with 8-azaguanine ...	1982	7180239
prevention of leptospira interrogans serovar pomona infection in cattle.	a commercial hardjo-pomona vaccine which has previously been shown to be effective against hardjo infection was tested against pomona. following challenge all 11 six-month-old non-vaccinated calves seroconverted and pomona was isolated from blood or urine on at least one occasion from nine of them. pomona was isolated once only, on the third day after challenge, from the blood of one of 11 vaccinated calves.	1982	16030839
surface colonies of leptospira interrogans.	observations of colonial growth of leptospira interrogans serovar pomona, bj, on soft-agar (1% agar) plates revealed the presence of both surface and subsurface colonies. the organisms from both types of colonies appeared to be similar in motility, morphology, antigenic composition, and pathogenicity. passage in vivo tended to produce a higher incidence of surface colonies, whereas passage in vitro tended to produce a higher incidence of subsurface colonies, suggesting the importance of environm ...	1981	7462407
immunogenicity of boiled compared with formalized leptospiral vaccines in rabbits, hamsters and humans.	leptospires (leptospira interrogans serovar pomona) grown in chemically defined medium were immunogenic when given intradermally in humans if the leptospires were killed with formalin but not if they were boiled. boiled leptospires were immunogenic for rabbits and hamsters and protected hamsters from challenge infection. on the other hand, boiled leptospires of the biflexa complex, serovar patoc, did retain some immunogenicity in humans, but the antisera did not protect hamsters against challeng ...	1980	7188698
maturation of humoral immune response determines the susceptibility of guinea-pigs to leptospirosis.	baby guinea-pigs were susceptible to infection with leptospira interrogans serovar pomona, but rapidly became resistant as they matured. increased resistance with increasing weight of guinea-pigs was correlated with the development of ability to produce agglutinating antibodies to leptospires and with maturation of b-cell dependent (but not t-cell dependent) areas in lymphoid organs. these observations can explain the basis of species-resistance of adult guinea-pigs to infection with serovar pom ...	1980	6970358
effect of chilling and freezing on survival of leptospira interrogans serovar pomona in naturally infected pig kidneys.		1979	292921
leptospira interrogans serovar pomona vaccines with different adjuvants in cattle.		1979	388262
plate assay for detection of leptospira interrogans serovar pomona hemolysin.	a plate assay which utilizes the addition of a blood agar overlay for detection of hemolysin by colonies of leptospira interrogans serovar pomona is described.	1979	528687
survival of leptospira interrogans serovar pomona in an acidic soil under simulated new zealand field conditions.	leptospira interrogans serovar pomona was found to survive for at least 42 days in a typical new zealand soil under simulated winter field conditions. the soil was markedly acidic with a ph of 5.5 and survival times were not reduced even when its water content was only 23%. the values of both these parameters are considerably less than previously recorded for the survival of leptospires in soil. two methods were used to recover leptospires from the soil microflora. one was the culture of a membr ...	1978	30123
hazards of disease transfer from marine mammals to land mammals: review and recent findings.	in a 5-year study (1972-1977) of microbial agents isolated from both clinically normal and diseased marine mammals, it was shown that certain disease agents are widespread in a diversity of ocean populations and that some are also transmissible to a number of terrestrial mammal species. leptospira interrogans serovar pomona has been isolated repeatedly from 2 species of pinnipeds (zalophus californianus califonianus and callorhinus ursinus). some of the more important bacterial pathogens for lan ...	1978	738931
susceptibility of mice treated with cyclophosphamide to lethal infection with leptospira interrogans serovar pomona.	mice not normally susceptible to infection with leptospira interrogans serovar pomona were rendered susceptible to lethal infections by treatment with a single dose of 300 mg of cyclophosphamide (cy) per kg administered optimally from 4 days before to 1 day after infection. cy-treated mice with either passively or actively acquired antibody were protected from death. blood levels of leptospires in infected untreated and in cy-treated mice remained similar until 2 days after infection, when untre ...	1976	965093