Biomedical subjects

J C Frantz

Publications and source records attributed to J C Frantz.

8 recordsLinked to original sources

PubMed1991

Reproductive failure associated with Leptospira interrogans serovar bratislava infection of swine.

Specimens from 17 swine herds experiencing reproductive failure were examined for Leptospira interrogans serovar bratislava. Clinical signs observed in these herds included stillborn pigs, weak neonatal pigs, and abortion. Diagnostic tests used to determine L. interrogans serovar bratislava infection were bacteriologic culture, serologic assays to detect antibodies, and immunofluorescence. Examination of fetal serum for antibodies against serovar bratislava and a fluorescent antibody test were the most practical diagnostic procedures.

Abortion, Veterinary↗

PubMed1991

Effects of purified Pasteurella multocida dermonecrotoxin on the nasal ventral turbinates of fattening pigs: histological observations.

Fattening specific pathogen-free derived pigs were injected intramuscularly with dermonecrotoxin of Pasteurella multocida, capsular type D. Ten days later, the nasal ventral turbinates and liver were examined histologically. A moderate turbinate atrophy was observed due to an increased number of osteoclasts and the absence of intramembranous bone apposition. Liver lesions were limited to some hepatocyte necrosis, sinusoid neutrophil infiltration and Kupffer cell hypertrophy. This study demonstrated that adult pigs are sensitive to P. multocida dermonecrotoxin.

Animals↗

PubMed1991

Atrophic rhinitis caused by Pasteurella multocida type D: morphometric analysis.

In order to study the distribution and the extent of atrophy caused by Pasteurella multocida in the nasal conchae, experimental piglets were injected intramuscularly at seven days of age with either two or four 50% mouse lethal doses per kg body weight of P. multocida type D dermonecrotoxin. Experimental and control piglets were killed four, six and ten days postinjection. Serial transverse paraffin embedded sections of the noses were cut throughout the entire length of the nasal conchae. The area of the nasal ventral conchae was measured and the morphometric index of the nasal cavity was calculated. It was observed that P. multocida type D dermonecrotoxin induced severe atrophy of the nasal ventral conchae. This atrophy was present along the entire conchae. However, it was most severe at the level of the first and second premolar teeth.

Animals↗

PubMed1990

Effects of purified Pasteurella multocida dermonecrotoxin on cartilage and bone of the nasal ventral conchae of the piglet.

The effect of intramuscular injection of purified dermonecrotoxin (DNT) from Pasteurella multocida type D on the nasal ventral conchae of piglets was studied. Severe atrophy of the conchae was observed 4, 6, and 10 days after injection (p.i.d). Lesions were observed in conchae cartilage and bone. Cartilage changes observed were the absence of chondrocyte maturation and hypertrophy, hyaline cartilage invasion by fibroblast-like and multinucleated cells, and endothelium damage with haemorrhages along the cartilage. Intramembranous bone was absent on p.i.d. 4, 6, and 10. Lamellar bone trabeculae were rarefied on p.i.d. 4 and almost absent on p.i.d. 10. Trabeculae were either normal or had the aspect of a dissolved bone matrix, leaving only irregularly oriented collagen fiber bundles. The number of osteoclasts was increased, especially the subperiosteal osteoclasts at the eccentric side of the scrolls. The osteoblasts appeared normal or their cytoplasm was dilated by vacuoles. It is concluded that the macroscopic conchae atrophy results from histological alterations and subsequent loss of both cartilage and bone. Further investigation is necessary to know whether the toxic effect of DNT on cells and matrix is direct or dependent of the vascular damage.

Animals↗

PubMed1989

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. In contrast, 233 of 311 (74.9%) sows and gilts given the 5-serovar bacterin farrowed. These results, as evaluated by analysis of variance techniques, showed a significant improvement (P less than 0.01) in reproductive performance for groups vaccinated against serovar bratislava.

Animals↗

PubMed1987

Investigation of synthetic Escherichia coli heat-stable enterotoxin as an immunogen for swine and cattle.

In its native form Escherichia coli heat-stable enterotoxin (STa) is nonantigenic; however, neutralizing antibodies are elicited in animals vaccinated with toxin-carrier conjugates. To study the immunogenicity of STa, peptides STa1-18 and STa5-18 were synthesized, characterized, and conjugated to carrier proteins. Pregnant gilts and heifers were hyperimmunized with the respective conjugates. Following parturition neonates were challenged with virulent E. coli (K99+ STa+). Peptides coupled to ovalbumin and emulsified with Freund adjuvant elicited antibodies that neutralized toxin-induced fluid accumulation in suckling mice. Peptides coupled to particulate carriers, with or without muramyl dipeptide adjuvant, failed to induce a measurable response. Peak antibody levels in sera were observed following three doses of conjugate and persisted for several weeks. The serological response in cattle was superior to that observed in swine; however, antibody levels in porcine colostrum were higher than those observed in cattle. Clinical observations of neonates from vaccinated dams indicated that passively obtained antibody provided partial protection from disease, but not as complete as that demonstrable with whole cell bacterins that induce antibody to pili. However, the data suggest the potential for utility of synthetically prepared antigens.

Animals↗

PubMed1986

Synthesis and antigenic activity of E. coli ST and its analogues.

Several enterotoxigenic E. coli (ETEC) are common causes of diarrhea in man and animals. These strains of E. coli produce two types of enterotoxins: heat-stable (ST) and heat-labile (LT). These toxins are peptides of molecular weight 2000 and 90,000 daltons, respectively. It is proposed that the synthetic analogues of these toxins could be effectively used as the vaccines against enterotoxigenic activity of E. coli. In this paper we report the isolation and chemical characterization of a heat-stable toxin STa. We also report the synthesis of this toxin and its analogues and their biochemical and immunological characterization.

Amino Acid Sequence↗

PubMed1979

Growth yields and fermentation balance of Bacteroides fragilis cultured in glucose-enriched medium.

Bacteroides fragilis is an obligate anaerobic bacterium classified with the gram-negative, non-sporeforming bacilli and is the Bacteroides species most frequently isolated from human infections. In the present study, experiments were designed to investigate growth characteristics of B. fragilis in a complex medium. In a minimal defined medium, which was employed for comparison purposes, B. fragilis grew with a generation time of 2 h. Growth of the organism in glucose-enriched medium used in the present study was superior. Maximum generation time was 60 min. Total and viable cells (colony-forming units) were 8.9 x 10(9) and 2.1 x 10(9), respectively, at maximum measurable growth. The molar growth yield (Ym) was 51.5. Growth yields were found to reach a maximum 2 to 3 h before maximum growth and to vary with respect to the phase of growth. Estimates of the fermentation products indicated that glucose was the sole energy substrate. Major products included acetic acid, propionic acid, lactic acid, and succinic acid. Other products included ethyl alcohol, pyruvic acid, and fumaric acid. No attempt was made to recover CO2 or formic acid. The OR balances from two experiments were 0.013 and -0.093 and the respective carbon recoveries were 6.268 and 6.241. The results of the present study show that B. fragilis is capable of rapid rates of growth in vitro by using glucose as the sole energy source.

Bacteroides fragilis↗