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Biomedical subjects

J F Timoney

Publications and source records attributed to J F Timoney.

At least 19 recordsLinked to original sources

Equine glomerulonephritis and renal failure associated with complexes of group-C streptococcal antigen and IgG antibody.

A 12-year-old thoroughbred gelding died from diffuse global glomerulonephritis, 3 months after a lower respiratory infection from which Streptococcus zooepidemicus was isolated. Immunopathological studies (immunofluorescence, immunodiffusion, immunoperoxidase testing and immunoblotting) indicated the presence of an immune reactant renal disease associated with IgG antibody and streptococcal antigens.

Animals

A convenient gel holder for preparative electrophoretic separation of aggregated bacterial proteins.

A simple custom-made gel holder for preparative SDS-PAGE to separate aggregated bacterial antigens is described. The gel holder fits easily into commercially available gel electrophoresis apparatus and proteins or peptides are collected in a stream of distilled water through a channel in the gel. The performance of the device was illustrated by the successful separation and purification of fragments of aggregated Streptococcus equi M protein and of Erysipelothrix rhusiopathiae protective antigens. Yields of up to 1.2 mg per run were obtained. The purified proteins retained immunological reactivity and were of sufficient purity for amino acid compositional and sequence analysis.

Antigens, Bacterial

Antigenic and genetic homogeneity of Streptococcus uberis strains from the bovine udder.

DNA- fingerprints (Hind III) of Streptococcus uberis field isolates from New York State and Europe showed substantial homogeneity, but were different to those of the type strain of the newly proposed psychrophilic species S. parauberis. S. uberis strains had major SDS-heat extracted antigens of molecular masses (Mr) less than 14, 40-41, 42-43, 59-61, 80-86 and 118-122 kDa following immunoblotting with rabbit hyperimmune sera. Bovine sera and milk reacted with the 40-41 and 118-122 kDa antigens. Variations in the Mr of particular bands were too unevenly distributed to permit formation of subgroups. Although cross reactive, the sizes of the antigens of S. parauberis strain NCDO 2020 were substantially different to those of S. uberis, the most prominent antigen having a Mr of 50 kDa. The antigenic and genetic data therefore strongly support the introduction of S. parauberis as a distinct species. S. uberis strains reacted with antiserum to Lancefield groups B, E, G and P, their grouping reactions showing no correlation with DNA and immunoblot fingerprints. Lancefield grouping of S. uberis therefore appears to have little value in identification.

Animals

Characterization of a protective protein antigen of Erysipelothrix rhusiopathiae.

Although vaccination is widely practiced against infection by Erysipelothrix rhusiopathiae in pigs and turkeys, the protective antigen(s) involved have not been fully characterized or purified to homogeneity. Antigens of E. rhusiopathiae strain T28, serotype 2b, and of FRANKFURT XI, serotype N, in culture supernatant and in extracts made with hot acid, 10 mM NaOH, ultrasound or EDTA were compared by SDS-PAGE and immunoblotting and in a mouse protection test. EDTA and 10 mM NaOH yielded highly protective extracts; culture supernatant was less protective and ultrasonic or hot acid extracts stimulated little or no protection in mice. Protective antisera from swine, horses and mice recognized prominent bands of molecular mass (m.m.) of 66-64 and 40-39 kDa in EDTA and 10 mM NaOH extracts. Mice immunized with preparations of the 66-64 kDa band purified by preparative electrophoresis were protected. Both antigens were trypsin sensitive, contained no detectable polysaccharide, and showed a marked tendency to aggregate in the absence of SDS.

Animals

A comparison of different methods of extraction of the M-protein from Streptococcus equi.

The molecular weights of the proteins produced in different extracts of Streptococcus equi were compared on immunoblots with antisera against acid extracted and mutanolysin extracted M-protein. Acid and alkaline extracts of S. equi contained some peptides of similar molecular weight that reacted with antiserum against an acid extracted 41,000 m.w. fragment suggesting that these fragments contained common epitopes. Comparison of the amino acid compositions of the 35,000 m.w. fragment of the alkaline extract and the 41,000 m.w. fragment of the acid extract suggest that these immunologically reactive fragments were probably derived from the same protein. Little cross-reactivity was observed between antisera against S. equi acid extracted protein and the native 58,000 m.w. M-protein. This suggests that conformational epitopes on the native M molecule are not present after acid treatment.

Amino Acids

Cloning and expression in Escherichia coli of a protective antigen of Erysipelothrix rhusiopathiae.

Erysipelothrix rhusiopathiae is a primary pathogen of swine and turkeys and sporadic cause of disease in a variety of other hosts, including humans. A genomic library of the highly virulent strain of E. rhusiopathiae E1-6P was constructed in the expression-cloning vector lambda gt11 and screened with serum from a pig convalescent from an E. rhusiopathiae experimental infection. Immunoreactive clones were screened for their ability to protectively immunized mice. Two clones, lambda gt11/ersA and lambda gt11/ersB, were obtained that protected mice against challenge with E. rhusiopathiae E1-6P. Antisera against the recombinant clones reacted with polypeptides of molecular weights 66,000, 64,000, and 43,000 in detergent-solubilized surface antigen preparations and whole-cell lysates of E. rhusiopathiae. These polypeptides were also the major antigens recognized by convalescent pig serum when reacted with the same preparations. Western immunoblot and Southern blot analysis revealed that the cloned genes and gene products were present in all of the E. rhusiopathiae strains tested.

Animals

Modified Feist broth as a serum-free alternative for enhanced production of protective antigen of Erysipelothrix rhusiopathiae.

The production of protective antigen in modified serum-free nutrient broth (H. Feist, K.-D. Flossmann, and W. Erler, Arch. Exp. Veterinaermed. 30:49-57, 1976) and in brain heart infusion broth supplemented with 10% horse serum (BHIS) was evaluated for six strains of Erysipelothrix rhusiopathiae serotypes 1a, 2, 2b, 4, and N. All six strains grew to higher cell densities in modified Feist medium than in BHIS and produced larger amounts of 64,000- to 66,000- and 39,000- to 40,000-molecular-weight antigens involved in immunity to erysipelas. A vaccine produced in Feist medium from E. rhusiopathiae SE-9 (serotype 2) was highly effective in a mouse protection test. We therefore suggest that modified Feist medium is an excellent, if not superior, alternative to BHIS for production of erysipelas vaccine.

Animals

Clonal groups of Salmonella typhimurium in New York State.

The epidemiology of 278 strains of Salmonella typhimurium isolated from 1973 to 1981 from animals in New York State was studied by using four "fingerprinting" techniques, bacteriophage type (B.R. Callow, J. Hyg. 57:346-359, 1959), biotype (J. P. Duguid, E. S. Anderson, G. A. Alfredsson, R. Barker, and D. C. Old, J. Med. Microbiol. 8:149-166, 1975), plasmid profile, and antibiogram. Phage type with biotype was the most useful marker for distinguishing clonal groups of S. typhimurium. Four clones of S. typhimurium predominated, i.e., phage type/biotypes U275/26, 49/26, 10/3, and 2/3. U275/26 and 49/26 were commonly found until 1976, but clones 10/3 and 2/3 were predominant after 1976. Comparison of results with data from Canada suggested a dissemination of strains of S. typhimurium between Canada and New York. Cattle were a common source of phage type 49, as has been observed in other countries.

Animals

Virulence determinants of Salmonella typhimurium from animal sources.

Two hundred seventy-eight strains of Salmonella typhimurium isolated from 1973 to 1981 from animal sources in New York State were studied for possible virulence determinants and for a serotype-specific plasmid possibly linked with virulence. Of the strains, 98% possessed type-1 fimbriae. All strains possessed flagella and were motile. One hundred twenty-three strains (44%) treated with mitomycin C tested positive for the cholera-Escherichia coli heat labile family of toxins by a kinetics-based ELISA; when treated with mitomycin C and extracted with polymyxin B, 249 (90%) were positive in the kinetics-based ELISA. All strains were negative in the Biken test. A smooth cell wall was found in 99% of the strains. Sixty-one percent (169) of the strains had a 62-Md plasmid. Seventy-six (27%) of the strains had detectable plasmids ranging in size from 1 to 124 Md.

Animals

Neuritis of the cauda equina, a chronic idiopathic polyradiculoneuritis in the horse.

Four cases of neuritis of the cauda equina (NCE) were studied by light and electron microscopy. Examination of sacral intradural rootlets revealed inflammatory cell infiltrates and an array of myelinated fiber changes which included myelin stripping by invading mononuclear cells and macrophages, as well as splitting and vesiculation of myelin lamellae without obvious participation by leukocytes. More distally in the extradural roots, there was marked granulomatous inflammation, and demyelinative changes were overshadowed by widespread evidence of irreversible axon damage. In all cases, unusual crystalline inclusions appeared in the endoneurium and sheaths of the rootlets and fascicles. The changes in NCE were compared and contrasted with those observed in acute and chronic inflammatory demyelinative neuropathies.

Animals

Vivo clearance of enteric bacteria from the hemolymph of the hard clam and the American oyster.

American oysters, Crassostrea virginica, and hard clams, Mercenaria mercenaria, were experimentally contaminated with Escherichia coli, Salmonella typhimurium, and Shigella flexneri either by intracardial injection or via the natural route of ingestion. Bacterial inactivation in the hemolymph was monitored for 72 h after exposure to these enteric pathogens at 20 and 6 degrees C. At 6 degrees C, both mean bacterial uptake by ingestion and subsequent clearance was singificantly lower that at 20 degrees C. However, substantial bacterial clearance from the hemolymph occurred for both shellfish at each temperature. At 20 degrees C, viable bacteria were no longer detectable after 24 h in hemolymph of either clams or oysters after exposure to contaminated water containing 4 x 10(3) bacteria per ml.

Animals

The epidemiology and genetics of antibiotic resistance of Salmonella typhimurium isolated from diseases animals in New York.

Only 12% of 249 strains of Salmonella typhimurium isolated during the period 1973-1976 from diseased animals were sensitive to six commonly used antibiotics. Isolates from calves exhibited the highest frequency of resistance as well as a steadily increasing frequency of resistance to ampicillin and chloramphenicol. The majority of strains from horses, dogs, and cats were also resistant to more than one antibiotic, a finding which was interpreted as primarily an effect of therapeutic rather than of growth-promoting use of antibiotics in these species. Ninety-one percent of resistant strains possessed transferable resistance. In 31% of these strains, the transfer factors were heat-sensitive and did not function at 37 C. The determinant of resistance to ampicillin was usually associated with a non-heat-sensitive transfer factor, whereas resistance to chloramphenicol, kanamycin, and tetracycline was more commonly associated with heat-sensitive transfer factors. Strains of S. typhimurium with similar patterns of resistance often contained different plasmids. There was more genetic homogeneity among determinants of resistance to tetracycline than among other determinants.

Ampicillin

Heavy-metal and antibiotic resistance in the bacterial flora of sediments of New York Bight.

The New York Bight extends seaward some 80 to 100 miles (ca. 129 to 161 km) from the Long Island and New Jersey shorelines to the edge of the continental shelf. Over 14 x 10(6) m(3) of sewage sludge, dredge spoils, acid wastes, and cellar dirt are discharged into this area each year. Large populations of Bacillus sp. resistant to 20 mug of mercury per ml were observed in Bight sediments contaminated by these wastes. Resistant Bacillus populations were much greater in sediments containing high concentrations of Hg and other heavy metals than in sediments from areas further offshore where dumping has never been practiced and where heavy-metal concentrations were found to be low. Ampicillin resistance due mainly to beta-lactamase production was significantly (P < 0.001) more frequent in Bacillus strains from sediments near the sewage sludge dump site than in similar Bacillus populations from control sediments. Bacillus strains with combined ampicillin and Hg resistances were almost six times as frequent at the sludge dump site as in control sediments. This observation suggests that genes for Hg resistance and beta-lactamase production are simultaneously selected for in Bacillus and that heavy-metal contamination of an ecosystem can result in a selection pressure for antibiotic resistance in bacteria in that system. Also, Hg resistance was frequently linked with other heavy-metal resistances and, in a substantial proportion of Bacillus strains, involved reduction to volatile metallic Hg (Hg degrees ).

Anti-Bacterial Agents

Feline salmonellosis. A nosocomial outbreak and experimental studies.

An outbreak of S. typhimurium gastroenteritis and septicemia is described in young cats admitted to a veterinary hospital for routine medical and surgical reasons. A morbidity of 32% and a mortality of 61% was observed in the outbreak. Affected cats exhibited oral shedding of the organism and contaminated feed and water dishes may have been the vehicle of spread of infection. Possible detrimental effects of incorrect choice of antibiotic therapy are discussed. Attempts to reproduce the disease in a group of laboratory cats were unsuccessful. Antibody production was poorly correlated with infection in these cats.

Animals

Bacteriophages of Streptococcus equi.

Bacteriophages were isolated from twelve lysogenic strains of Streptococcus equi. Based on sensitivity data and antiserum neutralization tests, the phage isolates were divided into two distinct but related groups. All twelve phage change the colonial morphology of S. equi from mucoid to matt. Possible phage-mediated effects on S. equi virulence are discussed.

Bacteriophage Typing

Salmonella in surface waters of central New York state.

Six tributary streams and southern Cayuga Lake in central New York state were sampled for the presence of Salmonella on swabs immersed for 4 days. Of a total of 322 swabs, 39% yielded salmonellae. Swabs were cultured in tetrathionate enrichment at 41.5 degrees C. Isolations were made from brilliant green agar. Salmonellae were isolated from many sites on the streams and from some lake sites. Twenty-five serotypes (11 somatic antigen groups) and a distinct biotype of S. typhimurium (H2S negative) were found. Most frequent isolates, in order of decreasing occurrence, were S. typhimurium, S. thompson, S. oranienburg, and S. enteritidis. Several uncommon isolates also appeared. When tested for mouse infectivity, the isolates generally showed little or no virulence. The incidence of clinical salmonellosis among humans was low in the area and the variety of serotypes had not been noted among cattle. The presence of Salmonella in waters ranging in classification from potable to agricultural and industrial indicated the existence of a low level and undefined reservoirs of the bacteria in the region.

Escherichia coli

Toxoplasmosis.

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Animals