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A B Thiermann

Publications and source records attributed to A B Thiermann.

At least 37 records · Page 2Linked to original sources
PubMed1986

DNA homology studies of leptospires of serogroups Sejroe and Pomona from cattle and swine.

Hybridization studies of chromosomal DNA from leptospiral strains representing Leptospira interrogans, serogroups Sejroe and Pomona from cattle and swine were performed to determine the degree of homology among their DNA sequences. Chromosomal DNA isolated from leptospires of the Sejroe and Pomona serogroups was radiolabeled and used to probe DNA isolated from other strains in these serogroups. Serovars hardjo (hardjoprajitno), hardjo (hardjo-bovis), balcanica (1627 Burgas), pomona (pomona), and kennewicki (LT-1026) were probed to determine the degree of homology among their chromosomes. Serovars pomona and kennewicki were homologous to each other. They also had a high degree of homology with hardjo (hardjoprajitno) and, to a lesser extent, with hardjo (hardjo-bovis) strains. However, hardjoprajitno and hardjo-bovis had little homology to each other. Serovar balcanica had a high degree of homology with hardjo-bovis isolates, but little homology with hardjoprajitno. Although serologically indistinguishable, the reference strain hardjoprajitno was genetically dissimilar to hardjo-bovis strains isolated from North American cattle.

Animals↗
PubMed1985

Identification and characterization of the protein antigens of Leptospira interrogans serovar hardjo.

We radiolabeled Leptospira proteins with [35S]methionine. Solubilized extracts of radiolabeled L. interrogans serovar hardjo strain hardjoprajitno were analyzed by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography. We compared the protein profile obtained in this manner to the protein profiles of various [35S]methionine-labeled Leptospira spp. The profiles of the pathogenic L. interrogans strains were very similar but not identical and exhibited no obvious relationship to those of the two nonpathogenic species. We used solubilized, radiolabeled hardjoprajitno extracts and a sensitive radioimmunoprecipitation procedure to identify protein antigens recognized by immunoglobulin G antibodies present in various rabbit anti-hardjo sera. Homologous hyperimmune rabbit serum efficiently precipitated a large subset of proteins, the majority of which were between 30,000 and 66,500 daltons. Radioimmunoprecipitations with sera prepared against each of four recent hardjo isolates cultured from infected cattle produced similar results. Immunoprecipitations done with various radiolabeled Leptospira extracts and anti-hardjoprajitno serum demonstrated that the pathogenic leptospires possessed a number of cross-reactive major and minor protein antigens. By cell fractionation procedures, we found that most of the major protein antigens were present in the outer envelope. These proteins were exposed on the leptospiral cell surface because intact radiolabeled leptospires bound antibodies directed against them.

Antigens, Bacterial↗
PubMed1985

New method for classification of leptospiral isolates belonging to serogroup pomona by restriction endonuclease analysis: serovar kennewicki.

The genomes of leptospiral field isolates belonging to serogroup Pomona were analyzed and compared with those of type strains by cleavage with restriction endonucleases. This new classification method shows differences among these organisms not indicated by the conventional serological typing method. No differences were observed among isolates from the United States, Canada, and New Zealand. Although all isolates selected for this study had been serologically typed as belonging to serovar pomona, the restriction endonuclease analysis indicates that they belong to serovar kennewicki. kennewicki, a serovar of North American origin, has recently been eliminated from the official serovar list because it was found to be indistinguishable from serovar pomona by the serological method.

DNA Restriction Enzymes↗
PubMed1985

Rapid and simplified protocol for isolation and characterization of leptospiral chromosomal DNA for taxonomy and diagnosis.

We have developed a rapid method for the isolation of leptospiral chromosomal DNA which yields DNA of a purity suitable for restriction endonuclease analysis. A small volume (15 to 20 ml) of an exponentially growing culture of leptospires yielded 2 to 4 micrograms of chromosomal DNA. In a 1-day protocol, the DNA was isolated, restricted with endonucleases, and fractionated on an agarose gel. Chromosomal DNA from dinger zones (visible subsurface zones of leptospiral growth) of first semisolid subcultures of field isolates was also isolated and characterized, thus greatly speeding up the diagnostic process.

Chromosomes, Bacterial↗
PubMed1985

Experimental infection of calves with Leptospira interrogans serovar hardjo: conjunctival versus intravenous route of exposure.

Eight-month-old calves, housed under maximum isolation, were exposed to pathogenic Leptospira interrogans serovar hardjo by the conjunctival route or IV. One calf served as an unexposed control. Infection was monitored serologically (microscopic agglutination test and enzyme-linked immunosorbent assay; ELISA) and by leptospiral culture isolation from periodic urine samples and from the kidneys, epididymides, and aqueous humor collected at slaughter. Microscopic agglutination test titers of greater than or equal to 1:40 were detected among all IV exposed calves at postinoculation day (PID) 7 and among conjunctival exposed calves at PID 14. By ELISA, all IV exposed calves were positive by PID 3, whereas conjunctival exposed calves were positive at PID 14. The ELISA was more sensitive for the detection of antibodies against leptospires in cattle. Leptospires were isolated from the urine of 4 calves and from the kidney of 3 calves exposed by the conjunctival route, but not from IV exposed calves. The results indicated that the conjunctival route of exposure was a more natural and successful route for experimental infection of cattle with serovar hardjo.

Agglutination Tests↗
PubMed1984

Isolation of leptospires in diagnosis of leptospirosis.

Though the microscopic agglutination test is commonly used as an aid to diagnosis of leptospirosis, it lacks sensitivity, cannot differentiate vaccinal titers from those of infection, and cannot identify shedders. The ELISA is sensitive but also cannot differentiate titers of vaccination and infection. Leptospire isolation is essential for a final diagnosis. Tissue or fluid samples should be aseptically collected, if possible, and quickly shipped to the diagnostic laboratory in transport medium or on ice, but should not be frozen. Samples to be collected may include urine, milk, kidney, aqueous humor, and fallopian tube or uterine mucosa.

Animals↗
PubMed1983

Bovine leptospirosis: bacteriologic versus serologic diagnosis of cows at slaughter.

Blood for serologic examination and kidneys for bacteriologic cultural examination were collected from 204 cows slaughtered in an Iowa packing plant during August to October 1981. By the microscopic agglutination test on the 200 serum samples which were collected, 29 (14.5%) were positive--22 samples (10.8%) had agglutinin titers to hardjo, 4 (2%) to pomona, and 5 (2.5%) to other serovars. With the enzyme-linked immunosorbent assay, 79 samples (39.5%) were positive--53 (26.5%) to hardjo and 36 (18%) to pomona. Leptospires were isolated from 13 (6.4%) of the kidneys (n = 204) examined. Characterization indicated that 7 isolates were hardjo; 3, grippotyphosa; and 2, pomona (1 isolate was lost during first subculture). Three of the hardjo isolates and 1 of the grippotyphosa isolates were obtained from cows that were seronegative by the microscopic agglutination test.

Agglutination Tests↗
PubMed1983

Enzyme-linked immunosorbent assay for the detection of antibodies to Leptospira interrogans serovars hardjo and pomona in cattle.

An enzyme-linked immunosorbent assay (ELISA), which used the phenol phase of a hot phenol-water extraction as antigen, and the microscopic agglutination test were compared for the detection of antibodies to Leptospira interrogans serovars hardjo and pomona in cattle. Among serum samples from vaccinated cattle, the ELISA (using antiglobulin) was positive to 64% with hardjo antigen and to 78% with pomona antigen, whereas the microscopic agglutination test was positive to only 18% with hardjo and 23% with pomona. There were no ELISA reactions observed among known negative-control samples. The ELISA, using antiglobulin conjugate, was overall a more sensitive technique for the detection of leptospiral antibodies in cattle.

Agglutination Tests↗
PubMed1982

Experimental leptospiral infections in pregnant cattle with organisms of the Hebdomadis serogroup.

The clinical and pathologic implications of leptospirosis caused by organisms of the Hebdomadis serogroup were tested on 8 pregnant cows. The animals were inoculated after their 5th month of pregnancy, 2 with serovar szwajizak and 6 with serovar hardjo. During the acute phase of the infection, the cows had mild signs of clinical illness; however, mastitis was observed in all cows that calved. One cow aborted, and 2 delivered premature and weak calves. By bacteriologic cultural examination, a short leptospiremic phase was observed. Leptospires were isolated from milk of 5 cows during early phases of mastitis; these isolations were obtained only when using solid media. Leptospiruria was determined by culture and direct examination. Only hardjo-inoculated cows had detectable urinary shedding which was observed to extend past 450 days in 1 cow. Leptospires were isolated from tissues of all cows and from 2 calves at necropsy. Interstitial nephritis was observed in all cows necropsied. Histologically, leptospires were demonstrated in silver-stained sections of kidney, liver, and lung of most calves. Leptospires were also observed in sections of kidney of all cows necropsied and in the cotyledons, placenta, and liver of some. Agglutinating titers were detected in the serum of cows as early as 4 days after inoculation and reached maximum titer (81,920) after 20 days. Significant serum titers persisted for the duration of the experiment only in hardjo-inoculated cows. At birth, all calves had no detectable agglutinins, but seroconverted within 24 hours; the serum titers were similar to those found in the dam's milk.

Animals↗
PubMed1981

Urban rats as chronic carriers of leptospirosis: an ultrastructural investigation.

Kidneys of six wild-trapped, adult Norway rats with high agglutinating titers to Leptospira icterohaemmorhagiae were examined ultrastructurally. Although many leptospires were seen in the lumen of proximal kidney tubules, few changes in epithelial cells of this region were found. The predominant lesion in chronic rat leptospirosis was diffuse interstitial nephritis. Principal kidney lesions were proximal tubule cell basement membrane thickening with or without the presence of granular particles, and an interstitial response that varied from mixed hypercellular to chiefly plasmacytic. The association of leptospires with membrane-bound protein droplets of the proximal kidney tubules may be important in the maintenance of the chronic carrier state in rat leptospirosis.

Animals↗
PubMed1981

The Norway rat as a selective chronic carrier of Leptospira icterohaemorrhagiae.

Laboratory raised wild Norway rat males (Rattus norvegicus) were injected with leptospires of two serovars: icterohaemorrhagiae and grippotyphosa. The development of a carrier state was monitored serologically, culturally and histologically. Rats infected with icterohaemorrhagiae developed rapidly into a chronic carrier state and shed leptospires in the urine for the duration of the experiment (220 days). At the time of necropsy, histopathologic studies showed evidence of leptospiral infections in the lumen of proximal convoluted tubules of some kidneys. Rats infected with grippotyphosa shed organisms for 40 days after inoculation; thereafter, they apparently cleared the infection. No organisms were detected histologically nor by culture at the end of the experiment (220 days). There appears to be a specific host-parasite relationship in the Norway rat towards becoming chronic carriers when infected with serotype icterohaemorrhagiae but not with grippotyphosa.

Animals↗
PubMed1981

Use of solid medium for isolation of leptospires of the Hebdomadis serogroup from bovine milk and urine.

Leptospira interrogans serovars hardjo and szwajizak were isolated from the milk of experimentally infected cows only when using bovine albumin polysorbate-80 solid medium. Semisolid media, with and without the addition of 5-fluorouracil, and hamster inoculations were also used in the isolation attempts. These cultural isolation methods were also compared using cows' urine. Semisolid medium with 5-fluorouracil proved to be the most successful. However, the other methods were satisfactory, with solid medium having the lowest percentage of cultural isolations.

Animals↗
PubMed1980

Opportunistic fungi in Detroit's rats and opossum.

Four Norway rats (Rattus norvegicus) and one opossum (Didelphis virginiana) were surveyed for the presence of fungi. Eighteen different fungi were isolated from rat samples and six from the opossum, including Trichophyton mentagrophytes. Hair and skin scrapings from laboratory raised Norway rats, bedding and air from the room yielded only Penicillium sp.

Animals↗
PubMed1980

Effect of cyclophosphamide treatment on clinical and serologic response of rats to infection with Leptospira interrogans serovar icterohaemorrhagiae.

Young albino rats were immunosuppressed with cyclophosphamide and exposed to virulent and low-virulence Leptospira interrogans serovar icterohaemorrhagiae 820K. In rats exposed to virulent and low virulence leptospires, microscopic agglutinating antibody responses occurred later, and longer leptospiremic phase and more massive tissue invasion by the organisms were observed in immunosuppressed rats than in immunocompetent controls. Clinical and pathologic signs of illness were more severe in the immunosuppressed animals than in immunocompetent controls. When exposed to low-virulence leptospires, immunosuppressed rats became infected and developed signs of illness and 2 of 16 died. Immunocompetent rats rapidly developed a humoral response and did not develop any signs of illness, and with 1 exception, organisms were not recovered from any tissues.

Animals↗