Search PubMed⌕ Search

Biomedical subjects

R S Roy

Publications and source records attributed to R S Roy.

48 records · Page 3Linked to original sources
PubMed1974

[An experimental study on the variation of serum antibody levels relative to the life cycle of the horsefly].

The changes of antibody titers in the sera of colts infested naturally or artificially with Gasterophilus have been determined in relation to the life cycle of this arthropod using passive hemagglutination, complement fixation, double diffusion techniques and saline extracts of antigens from the third larval stages of Gasterophilus intestinalis and G. nasalis.In the sera of the infected animals the hemagglutinating antibodies were present at low titers at the third week post-infestation by using somatic extract of G. intestinalis and at the seventh week in case of G. nasalis. At eight weeks post-infestation the antibody titers reached their maximum 1:8192 (G. intestinalis) and 1:4096 (G. nasalis), then dropped at 12 weeks post-infestation. The complement fixing antibodies were present occasionally between the seventh and 11th weeks after infestation. Precipitating antibodies were absent in all sera.

Animals↗
PubMed1973

A simple procedure for the preliminary identification of aerobic gram negative intestinal bacteria with special reference to the Enterobacteriaceae.

A useful procedure is described for rapid identification of some Gram negative bacteria during quantitative studies of the intestinal flora from various species. The methods used are based on primary isolation and differentiation of the bacteria by the use of MacConkey agar and the subsequent differentiation according to definite procedure using the replica plating technique.

Aerobiosis↗
PubMed1973

[Quantitative study of the bacterial flora of the large intestine of dysenteric swine].

The bacterial flora and the pH of the large intestine of dysenteric swine during acute subacute and chronic phases have been submitted to quantitative and qualitative studies. The methods used are based on primary isolation and differentiation of the bacteria by the use of selective media and the subsequent differentiation using the replica plating technique. The most characteristic changes are the following:1. A significant increase of the pH of the chyme in the large intestine during acute dysentery2. A significant increase of Vibrio, Escherichia coli and Staphylococcus in the colon and cecum during acute dysentery.3. A significant increase of Shigella in the colon and cecum during subacute dysentery.4. The almost total disappearance of Aeromonas and of the yeasts in the large intestine during acute, subacute and chronic dysentery.5. A significant decrease of Klebsiella, in the cecum, during acute dysentery and of the fungi during subacute dysentery.6. Decrease of Streptococcus in the colon during acute dysentery.7. The total quantitative flora of the large intestine do not change very much.

Aeromonas↗
PubMed1973

A preliminary study on the intestinal flora of cecum and colon of eight, ten and 12 week old swine.

Using a replica-plating method and differential culture media, members of the Enterobacteriaceae and Pseudomonaceae were determined quantitatively in the colon and cecum content of pigs from different litters, born on the same farm and kept under the same environmental conditions, from the age of six weeks. The bacterial flora in pigs of eight, ten and 12 weeks of age showed little significant quantitative variation. Pigs of 12 weeks of age differed significantly from younger ones with respect to Aeromonas, Edwardsiella, staphylococci and molds. The existence of a variable flora is underlined as well as the fact that Vibrio coli represents an important member of the intestinal flora at that age. No significant variation in the pH of the chyme of the colon and cecum was recorded.

Aeromonas↗
PubMed1973

Concentration of IgG in serum and large intestine of dysenteric swine.

Radial immunodiffusion tests employing swine IgG monospecific antiserum have permitted the determination of the IgG concentration in the serum and large intestine of healthy and dysenteric 12 week old boars. Specific and significant increases in IgG were observed in serum and colon during the acute from of the disease, but in the cecum only, during the subacute phase of the disease.

Animals↗
PubMed1972

[R factors in strains of pathogenic enterobacteria isolated from domestic animals and particularly from dogs].

Strains of enterobacteria (nine Escherichia coli and two Salmonella) isolated from primary or secondary infections in the dog, cat, pig, calf and kangaroo were studied for the presence of extrachromosomal drug resistance factors (R factors). Seven strains of E. coli and two strains of Salmonella transferred resistance involving the following antibiotics: streptomycin, ampicillin, chloramphenicol, neomycin and tetracycline. All strains harboring R factors transferred streptomycin resistance and the identified resistance patterns were as follows: Sm Am, Sm Te, Sm Neo, Sm Am Te, Sm CI Neo and Sm Am CI Te. The levels of resistance observed were comparable for all donor strains and their converted recipients. Strains of E. coli harboring R factors were isolated from three dogs that had died of either otitis (followed by a generalized infection), enteritis or bronchopneumonia - secondary to distemper. The bacteria isolated from cats were recovered at the necropsy of animals that had died of purulent pleuresy and feline panleukopenia. The other strains (two Salmonella and one E. coli were isolated from fatal enteric diseases in the pig, calf and kangaroo.

Ampicillin↗
PubMed1972

Irish hospitals.

Explore the source record for details and available documents.

Hospitals↗
PubMedDate not supplied

A simple technique for preparation of chicken-embryo-skin cell cultures.

A simple, rapid technique was developed for preparing chicken-embryo-skin cell cultures utilizing trypsinization of the skin of intact 12-day-old chicken embryos. When cell cultures were inoculated with fowl pox virus, those that consisted of at least 80% epithelial cells yielded a higher virus titer than fibroblast cell cultures.

Animals↗
PubMedDate not supplied

Antigenic relatedness between seven avian mycoplasma species as revealed by western blot analysis.

Cross-reactivities among seven avian mycoplasma species (Mycoplasma gallisepticum, M. synoviae, M. meleagridis, M. iowae, M. anatis, M. gallinarum, and M. iners) were examined using rabbit polyclonal antisera and two monoclonal antibodies (MAbs) against M. pneumoniae: Myc-9 and Myc-4. The major antigens and cross-reacting antigens of the seven mycoplasma species were demonstrated by immunoblotting assay using homologous and heterologous antisera. Two-way cross-reacting antigens of MS and MG, with apparent molecular weights of 44,000 and 36,000, were identified. Additionally, the 36,000 protein of MG was recognized by all of the heterologous antisera. A large number of cross-reactivities, which have been never investigated before, were shown between M. meleagridis and M. synoviae, between M. meleagridis and M. gallinarum, between M. meleagridis and M. iners, and between M. gallinarum and M. iners. All of the cross-reactions existing between the majority of the above species were considerably reduced or eliminated by adsorbing the polyclonal antisera with a pool of heterologous antigens. Two MAbs against a M. pneumoniae protein of a molecular weight of 150,000 were also able to recognize several avian mycoplasma epitopes, of which two common epitopes with molecular weights of 44,000 and 42,000 were present in most of the seven mycoplasma species.

Animals↗
PubMedDate not supplied

An enzyme-linked immunosorbent assay for detection of avian mycoplasmas in culture.

An antigen-capture enzyme-linked immunosorbent assay (ELISA), using monoclonal antibody (Myc-9) against Mycoplasma pneumoniae, was developed for the detection of M. gallisepticum, M. synoviae, M. meleagridis, M. iowae, M. anatis, M. iners, and M. gallinarum antigens in cultures. ELISA plates were coated with Myc-9 and reacted with the different avian mycoplasma antigens, which were detected with adsorbed polyclonal anti-mycoplasma serum followed by anti-rabbit enzyme-labeled conjugate antiserum. Nonspecific reactions and cross-reactivity were eliminated by adsorbing polyclonal antisera with a pool of heterologous antigens, and a high degree of sensitivity was obtained by both antigen enrichment and treatment with the detergent N-octyl glucoside. Under these conditions, the test detected less than 10 colony-forming units/ml. This antigen-capture ELISA appears to be a highly specific, sensitive, reproducible tool and efficient in the diagnosis of mycoplasma infection.

Animals↗