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R C Giles

Publications and source records attributed to R C Giles.

At least 37 records · Page 2Linked to original sources
PubMed1984

Molecular localization of human class II MT2 and MT3 determinants.

The specificities of the monoclonal antibodies I-LR2 and 109d6, which recognize MT2- and MT3-like serologic determinants, respectively, have been confirmed by panel testing. In addition, the relationships of these antibodies to other monoclonal antibodies and alloantisera have been studied by means of cell surface fluorescence, complement-dependent cytotoxicity and immunoprecipitation. Using these monoclonal antibodies, molecules encoded by the HLA-D region have been isolated and characterized by amino acid sequencing and peptide mapping. By these criteria, the major populations of molecules bearing MT2- and MT3-like determinants are indistinguishable from DR molecules.

Amino Acid Sequence↗
PubMed1984

Primary structural variation among serologically indistinguishable DS antigens: the MB3-bearing molecule in DR4 cells differs from the MB3-bearing molecule in DR5 cells.

HLA-DS molecules bearing the MB3 supertypic specificity have been isolated from two DR4 and two DR5 homozygous cell lines by using the monoclonal antibody IVD12 . Limited amino-terminal amino acid sequence analysis of these molecules demonstrates polymorphism of the HLA-DS subregion. Although the distribution of amino-terminal tyrosine residues in the alpha-chains of all IVD12 -reactive molecules was identical, amino-terminal amino acid sequence differences existed between DS beta-chains isolated from these two groups of cell lines bearing different DR specificities. These studies indicate that two DS molecules bearing the same serologic determinant ( MB3 ), although similar to one another, may be structurally distinct.

Amino Acid Sequence↗
PubMed1984

Expression of HLA-DR, MB, MT and SB antigens on human mononuclear cells: identification of two phenotypically distinct monocyte populations.

The expression of HLA-DR, SB, MB, and MT antigens in different populations of human mononuclear cells was investigated with the use of monoclonal antibodies that recognize distinct human Ia-like antigens. Our results indicate that in man, as previously reported in other species, two phenotypically distinct populations of monocytes or macrophages can be identified on the basis of expression of Class II MHC antigens. Virtually all circulating monocytes displayed determinants associated with HLA-DR, SB, and MT. In addition, a subpopulation of human monocytes expressed MB/DS-associated antigens, as detected with monoclonal antibodies specific for MB1, MB3, and DS-framework determinants. Most B lymphocytes expressed antigens associated with HLA-DR, and the specificities SB2, SB3, MB1, MB3, MT2, and MT3 were also present. Resting T lymphocytes were unreactive with antibodies that recognize all of the Class II MHC antigens tested. T lymphocytes activated by soluble antigen or alloantigens, and expanded in culture, expressed DR, SB, MB, and MT. The majority of the MB/DS+ cells present in the adherent population were monocytes, because they were phagocytic and had the monocyte-specific marker 63D3. The rest of the cells were not identified. They are likely to include mostly B lymphocytes. The presence of other cells, such as dendritic cells, in this subset needs to be determined.

Antibodies, Monoclonal↗
PubMed1983

Myodegeneration in Kentucky white-tailed deer.

Skeletal or cardiac myodegeneration, or both, was observed in 4 free-ranging female white-tailed deer that were found dead or recumbent and unable to rise. Gross pathologic findings included white or chalky streaks in heart or skeletal musculature. Degeneration, necrosis, and mineralization were observed microscopically in affected striated muscles. Although the precise cause of myodegeneration was not determined, changes were considered compatible with nutritional or exertional myopathy.

Animal Population Groups↗
PubMed1983

Structural analysis of a human I-A homologue using a monoclonal antibody that recognizes an MB3-like specificity.

Monoclonal antibody IVD12 was used to isolate and characterize a human Ia molecule present on B cells that generally display DR4 or DR5 phenotypes. The specificity of binding of IVD12 to human peripheral blood B cells from 75 normal individuals and 19 homozygous human lymphoblastoid B cell lines was identical to the supertypic specificity MB3 previously defined. Furthermore, IVD12-reactivity was shown to segregate with HLA in three informative families. In each family, individuals positive for IVD12 binding were also positive for DR4 or DR5. Using IVD12, a molecule has been isolated from the homozygous cell line PRIESS (DR4/4) and has been shown by amino acid sequence analysis to be homologous to the murine I-A and human HLA-DS molecules. These findings suggest that the MB3 specificity is found on a molecule encoded by loci distinct from those loci which encode HLA-DR molecules. This molecule represents the third family of HLA-D region molecules isolated from the cell line PRIESS. Both HLA-DR and HLA-SB molecules from this cell line were previously shown by amino acid sequence analysis to be I-E-like but distinct from one another. Collectively, these data provide evidence that the HLA-D region contains at least six loci encoding distinct alpha and beta chains for the HLA-SB, HLA-DR, and HLA-DS molecules.

Amino Acid Sequence↗
PubMed1983

Intramolecular heterogeneity of ligand binding by two IgM antibodies derived from murine hybridomas.

The ligand binding properties of two murine anti-DNP IgM hybridoma antibodies were analyzed. These IgM antibodies, designated NP3-17 C1-20 and SP2/0 I-64 C1-12, each displayed an average of only five high affinity binding sites for the DNP moiety. Reductive 7S subunits of both of these proteins each adsorbed to and were hapten eluted from DNP affinity columns. These subunits, when examined by equilibrium dialysis, each contained an average of one high affinity binding site. Structural analysis of these molecules indicated each to be homogeneous. Results obtained from trypsin hydrolysis of each molecule indicated that differences in conformation of the binding sites may account for the observed binding heterogeneity.

Aminocaproates↗
PubMed1982

Sarcocystosis in an aborted bovine fetus.

Sarcocystosis was diagnosed in an aborted bovine fetus. Immature and mature schizonts of Sarcocystis were disseminated in the vascular endothelium of all organs, but especially the brain. Microscopic granulomas, focal gliosis, and petechial hemorrhages in the neuropil were scattered in the brain. Multifocal collections of mononuclear cells were observed in the kidney, liver and heart. Organisms in sections of frozen tissues were demonstrated by immunofluorescent techniques to be Sarcocystis.

Abortion, Veterinary↗
PubMed1982

Effects of prochlorperazine on experimental nephrotoxicity.

In early studies of the antitumor drug 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1nitrosourea (methyl-CCNU), animal models consistently predicted that the compound would be nephrotoxic in humans. Nephrotoxicity in cancer patients who had received methyl-CCNU was not confirmed until about 6 years after clinical trials began. We have investigated the possibility that prochlorperazine, a commonly used antiemetic, might affect the development of nephrotoxicity. Prochlorperazine (1, 2, 5, and 8 mg/kg IP on days 1-3) produced a dose-related reduction in the concentrations of plasma urea nitrogen in mice that received nephrotoxic doses of methyl-CCNU (42, 52, or 63 mg/kg IP on day 1). The frequency and severity of renal lesions evaluated histopathologically were reduced significantly as the prochlorperazine dose increased. To study further this apparent protective activity of prochlorperazine, we chose a second nephrotoxin, mercuric chloride (HgCl2, 1 mg/kg IP on day 1) and a rodent species used more commonly as a model for nephrotoxicity, the rat. Prochlorperazine (2.5 or 10 mg/kg IP on days 1-5) inhibited HgCl2-induced urinary excretion of N-acetylglucosaminidase and leucine aminopeptidase. Urinary excretion of these enzymes on day 1 reflected proximal tubular epithelial degeneration and necrosis in rats that received HgCl2 alone. The severity of HgCl2-induced renal lesions evaluated histopathologically on day 16 was significantly reduced by combination treatment with prochlorperazine. Phenothiazines have numerous pharmacologic properties that might account for this observation, and additional studies will be required to establish the mechanism of this protective effect of prochlorperazine against acute nephrotoxicity in rodents.

Animals↗
PubMed1980

Sarcocystosis in cattle in Kentucky.

Sarcocystosis was diagnosed in 41 eighteen-month-old heifers and steers. Clinical signs included anorexia, severe weight loss, nervousness, hypersalivation, lameness, and hair loss on the extremities. Hair loss was noticed especially at the end of the tail, where there was complete loss of the switch, giving the animals a "rat-tail" appearance. Consistent gross changes observed at necropsy of four affected animals included generalized lymphadenopathy, erosions and ulcerations in the oral cavity and esophagus, and severe laminitis. Microscopically, young cysts of Sarcocystis sp were disseminated in the heart, skeletal muscle, and brain. Ultrastructural examination indicated that the cysts were young because they contained metrocytes. Affected animals had moderate to severe nonsuppurative myocarditis and myositis, with focal degeneration of myofibers and infiltration by macrophages, lymphocytes, and plasma cells. Indirect hemagglutination of sera from 19 animals revealed a mean antibody titer of 1:24,000 against Sarcocystis bovicanis antigen. Epidemiologic investigation incriminated resident farm dogs that had been housed in a farm hayloft as the source of infection. Hay contaminated with sporocysts in dog feces was thought to have been fed to the heifers and steers.

Animals↗
PubMed1980

Malignant mammary tumors in beagle dogs dosed with investigational oral contraceptive steroids.

Of 172 beagle dogs administered investigational oral contraceptive steroids for 2.4-5.2 years, 9 developed malignant mammary tumors. At necropsy their ages varied from 41 to 70 months, with a mean age of 4.9 years. The malignant tumors were observed in 1 dog that received ethynerone plus mestranol at 1.05 mg/kg/day and in 4 dogs that received chlorethynyl norgestrel plus mestranol at 1.05 mg/kg/day. Also, 4 dogs that received anagestone acetate plus mestranol at either 0.44 or 1.10 mg/kg/day developed malignant mammary tumors. Malignant tumors were not seen in 33 dogs administered mestranol at 0.02 and 0.05 mg/kg/day for 7 years or in 18 dogs given ethynerone without mestranol at 1.00 mg/kg/day for 5 years. No malignant tumors were observed in 18 control dogs maintained for 7 years without treatment. Three dogs had single malignant mammary nodules, 3 dogs had 2 malignant nodules, 2 dogs had 4-6 malignant nodules, and 1 dog in the treatment group given high dosages of ethynerone plus mestranol had 14 mammary nodules composed of fibrosarcoma. The malignant tumors were histologically classified as 5 anaplastic carcinomas, 2 solid carcinomas, 1 tubular adenocarcinoma, 1 squamous cell carcinoma, and 1 fibrosarcoma. Most dogs had only 1 histologic type of cancer (8/9 dogs); however, 1 dog had carcinomas of both solid and anaplastic types involving different glands. Metastases were present in 5 dogs and most often involved regional lymph nodes and lung.

Adenocarcinoma↗
PubMed1978

Mammary nodules in beagle dogs administered investigational oral contraceptive steroids.

Of 172 beagle dogs administered oral contraceptive steroids for 5-7 years, 114 developed 1,156 nodules in the mammary gland region. Most of these nodules arose 2.5-3.5 years after initiation of treatment. Approximately 16% of the nodules were transient and disappeared spontaneously from the mammary gland during the study. A total of 925 nodules were present in 99 dogs at the time of death or necropsy. These nodules were classified as benign mammary dysplasias (7.0%), lobular or intraductal hyperplasias (31.4%), simple adenomas (20.8%), complex adenomas (25.4%), benign mixed tumors (5.3%), malignant tumors (3.6%), or nonmammary lesions (6.5%). Histologically, the mammary nodules were representative primarily of the hyperplasias and tumors that occur spontaneously in the mammary glands of the dog. The only major exception was the presence of 82 simple adenomas that had basaloid features. Most of the contraceptive-related mammary nodules developed in dogs receiving the combination of progestion and mestranol at 10 or 25 times the proposed human dosage. Control dogs and dogs receiving mestrenol alone had few mammary nodules. Combinations of anagestone acetate and mestranol and chloroethynyl norgestrel (WY-4355) and mestranol produced large numbers of nodules at 10 and 25 times the proposed human dosage, whereas ethynerone plus mestranol produced large numbers of nodules only at 25 times the proposed human dosage. Ethynerone, when given alone at 25 times the proposed human dosage, was associated with fewer mammary nodules. Malignant neoplasms were seen in dogs given 10 and 25 times the proposed human dosage of anagestone acetate plus mestranol and 25 times the proposed human dosage of WY-4355 plus mestranol and ethynerone plus mestranol. This study strongly associates certain combinations of progestin and mestranol with mammary neoplasia in dogs.

Adenoma↗
PubMed1977

Use of 59Fe for sheep erythrocyte kinetic studies.

Erythrocyte (RBC) survival time as determined by in vivo 59Fe-labeled RBC in 6 adult sheep was 111.7 (SEM +/- 8.4) days. The plasma clearance (T/2) of 59Fe was 148 (+/- 17.3) minutes and the maximum RBC uptake of 59Fe was 52.4% (+/- 3.6%). Plasma iron turnover rate was 0.356 (+/- 0.016) mg/kg/24 hours, and RBC iron turnover rate was 0.186 (+/- 0.016) mg/kg/24 hours. Blood volume measurement was 53.5 (+/- 3.9) ml/kg of body weight.

Animals↗