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Biomedical subjects

C Olson

Publications and source records attributed to C Olson.

At least 37 records · Page 2Linked to original sources
PubMed1985

Mechanisms of chain initiation in the biosynthesis of connective tissue polysaccharides.

Carbohydrate-protein linkages of three types are found in the connective tissue proteoglycans; these linkages involve the following monosaccharide-amino acid pairs: xylose-serine; N-acetylglucosamine-asparagine; and N-acetylgalactosamine-threonine (or serine). The biosynthesis of carbohydrate groups containing linkages of the latter two types presumably occurs by the same pathways that have been well established for many glycoproteins, but details of these processes as they pertain to proteoglycans are not yet known. Initiation of polysaccharide chains linked by the xylose-serine linkage takes place by direct transfer of xylose from UDP-xylose to the hydroxyl groups of specific serine residues in the core proteins of the respective proteoglycans, and the xylosyltransferase catalyzing these reactions has been detected in the rough endoplasmic reticulum of embryonic chick chondrocytes. Although the completed or nascent core proteins are the natural substrates for xylose transfer in the intracellular assembly of proteoglycans, a survey of potential exogenous substrates has shown that small peptides containing alternating serine and glycine residues may also serve as acceptors in this reaction. Nevertheless, larger substrates are preferred, such as chondroitin sulfate proteoglycan, which has been deglycosylated by Smith degradation or HF treatment, or silk fibroin, which contains Ser-Gly pairs. In contrast to the sulfated polysaccharides, which are synthesized by carbohydrate transfer to protein in the endoplasmic reticulum and the Golgi apparatus, hyaluronic acid is formed in the plasma membrane by a different mechanism. The reaction by which chains are initiated is not yet known, but recent work by Prehm suggests that this process occurs either by transfer of the glucuronosyl component of UDP-glucuronic acid to UDP-N-acetylglucosamine or by the converse reaction, i.e., transfer of the N-acetylglucosaminyl unit of UDP-N-acetylglucosamine to UDP-glucuronic acid.

Acetylgalactosamine↗
PubMed1980

Immunologic relatedness of papillomaviruses from different species.

An antiserum prepared by immunization of a rabbit with sodium dodecyl sulfate-disrupted virions from a pool of plantar warts was cross-reactive with virus-positive papillomas of other animal species by both indirect immunofluorescence tests on frozen sections of wart tissues and peroxidase-antiperoxidase tests of sections of Formalin-fixed tissues. The antiserum stained plantar warts, common warts, and skin lesions of epidermodysplasia verruciformis, all from humans; bovine fibropapilloma, experimentally produced with bovine types 1 and 2; and transmissible canine oral papillomas. The staining was localized to nuclei of the upper granular layers of the peithelium and was similar in distribution to the pattern produced by antiserum specifically prepared against that papillomavirus. The antiserum did not stain virus-negative warts, or cells infected with simlan virus 40, human polyomavirus BK, and murine polyomavirus. These data suggested that papillomaviruses share a common internal antigen unrelated to a similar antigen described previously for the polyomaviruses (which include simian virus 40 and polyomavirus subgroups).

Animals↗
PubMed1979

Hybridization of bovine papilloma virus type 1 and type 2 DNA to DNA from virus-induced hamster tumors and naturally occurring equine tumors.

DNAs from bovine papilloma virus(BPV)-induced hamster tumors and from equine connective tissue tumors of unknown etiology were examined for BPV DNA sequences by molecular hybridization. DNA from two distinct classes of BPV (type 1 and type 2) was labeled in vitro and used as probes. Analysis of DNA-DNA reassociation kinetics indicated that both virus types were capable of tumor induction in the hamster. DNA isolated from 6 of 7 equine tumors accelerated the reassociation of the BPV DNA probes. BPV type 1 or type 2 DNA hybridized extensively to DNA from 3 tumors, while 3 other tumors contained DNA sequences to which only a portion of the probes hybridized. Partial hybridization of probe DNAs to tumor DNA suggested the possible existence of a third BPV class.

Animals↗
PubMed1978

Common membrane neoantigens on bovine papilloma virus-induced fibroma cells from cattle and horses.

Cultured cells from bovine papilloma virus (BPV)-induced fibroblastic tumors and normal dermis of cattle, horses, and hamsters were examined for cell membrane or internal neoantigens, using the indirect immunofluorescence technique. Sera from cattle and horses bearing BPV-induced fibromas cross reacted with cell membranes of tumor, but not with normal dermal cells of both species. The reaction could be blocked with homologous, but not heterologous, serum of these 2 species. Immunofluorescence was not detected with sera from hamsters bearing BPV-induced sarcomas if incubated with bovine, equine, or hamster cells. Internal neoantigens were not found in any of the acetone-fixed tumor cells, using sera from the 3 species. Both tumor and normal cells were all found free of BPV antigen, using direct immunofluorescence.

Animals↗
PubMed1978

Tumor-associated antigen and cell surface marker in cells of bovine lymphosarcoma.

The detection of tumor-associated antigen and B cell surface marker was attempted in lymphoid cells of peripheral blood (PBL) and lymph nodes obtained from cattle with lymphosarcoma, cattle infected with bovine leukosis virus (BLV), and clinically normal cattle. As a result, specific tumor-associated antigen was found in PBL and lymphoid tumor cells from cattle with the adult form of lymphosarcoma (ALS) using anti-ALS serum. The antigen was also detected in PBL of BLV-infected cattle. A weak reaction for the antigen was found in 2 of 5 cases of calf form. No significant reaction for the tumor-associated antigen of neoplastic lymphoid cells from ALS was found in the thymic and skin forms. The percentage of B cells in PBL and lymph nodes from ALS was higher than that in normal cattle. However, a loss of B cell surface marker was suggested in some ALS cases. A good relation was obtained between an increased B cell percentage and an appearance of the tumor-associated antigen in PBL of BLV-infected cattle. In lymphoid cells of PBL and lymph nodes from sporadic cases, the percentage of B cells was lower than that observed in normal cattle.

Animals↗
PubMed1978

Development of bovine leukosis virus infection in cattle. A preliminary study.

A serological study in three herds for 5 to 7 years indicated that BLV infection usually developed when cows where 2 to 4 years old, thereafter, the rate of new infection was somewhat less. The reactor status of the dam had no influence on whether or not and when progeny became reactors. In only one herd 3 calves from 57 reactor cows become persistent reactors, thus there was little evidence of vertical transmission. Such can occur where there is a break in the placental barrier.

Age Factors↗
PubMed1977

Location of antigens associated with bovine leukemia virus.

Antigens associated with bovine leukemia virus (BLV) infection (gp 44/55 and p23) were identified by neutralization and immunofluorescent antibody (FA) tests. Only serums containing antibody to gp 45/55 neutralized the virus; antibody to p23 did not. These results indicate that gp 44/55 may be located in the virus envelope. In indirect FA tests, both a cytoplasmic fluorescence and a membrane fluorscence were detected in BLV-infected cells. The serum used in the FA test was then absorbed with either p23 or gp 45/55. The results of these absorption tests indicate that the membrane fluorescence maybe associated with gp 45/55 and the cytoplasmic fluorescence may be associated with p23.

Absorption↗
PubMed1977

Inhibition of bovine leukemia virus release by antiviral antibodies.

Peripheral blood lymphocytes from bovine leukemia virus (BLV) infected cattle were grown in vitro with serums from BLV-infected and uninfected cattle, sheep and rabbits. Only serums from infected animals which had antibody to gp 45/55, the major glycoprotein antigen, inhibited the release of virus from the cells. Although viral antigens could be detected in the cells themselves, none were detected in the supernatants of cultures grown with these serums. Normal serums and serums with antibody only to p23, the internal BLV antigen, did not inhibit virus release. To identify the factor responsible for virus release inhibition, 2 inhibitory serums were absorbed with either gp 44/55, p23 or tissue culture cells from BLV-infected and uninfected cells lines. The results indicated that antibody to gp 45/55 is the factor responsible for virus release inhibition.

Absorption↗
PubMed1977

Pitch changes during attempted deception.

Two studies on speech samples from 32 male college students are reported. In the first, it was shown that the average voice fundamental frequency of the subjects was higher when lying than when telling the truth. In the second, judges rated the truthfulness of 64 true and false utterances either from an audiotape that had been electronically filtered to render the semantic content unintelligible or from an unfiltered tape. The truthfulness ratings of the judges who heard the content-filtered tape were negatively correlated with fundamental frequency, whereas for the unfiltered condition, truthfulness ratings were uncorrelated with pitch. Although raings made under the two conditions did not differ in overalll accuracy, accuracy differences were found that depended on how an utterance had been elicited originally.

Arousal↗
PubMed1977

Bovine papilloma virus: presence of virus-specific DNA sequences in naturally occurring equine tumors.

Four of five spontaneous benign equine connective tissue tumors of unknown etiology and a bovine papilloma virus (BPV)-induced equine tumor contained BPV-specific DNA sequences as determined by DNA-DNA hybridization of DNA from tumors with BPV DNA labeled in vitro. Analysis of the kinetics of reassociation indicated that 20-75% of the BPV genome was present in the various tumors. The number of partial BPV genome equivalents ranged from 60 to 500 copies per diploid quantity of cellular DNA. Thermal denaturation profiles of duplexes formed between labeled BPV DNA and DNA from tumor cells indicated two tumors contained viral DNA with base sequences identical to BPV DNA. Three tumors (including DNA from the BPV-induced tumor) contained BPV-related DNA sequences that were less thermally stable. The decrease in thermal denaturation temperature may be due to the presence of (adenine + thymine)-rich regions of the BPV genome in the tumor cells.

Animals↗
PubMed1977

Concanavalin A and the production of bovine leukemia virus antigen in short-term lymphocyte cultures.

The influence of the mitogen concanavalin A (Con A) on the production of bovine leukemia virus (BLV) antigen in short-term lymphocyte cultures was determined by means of a single radial immunodiffusion test. Con A did not affect viral antigen production in peripheral blood lymphocytes from 60% of both experimentally and naturally infected cattle. Antigen production was stimulated by Con A in lymphocytes from 28% of the cattle, but it was inhibited in lymphocytes from 12%. Similar results were also obtained with lymphocytes from both blood and lymph nodes from 10 cattle with lymphosarcoma and from 10 clinically normal cattle with histologically normal lymph nodes. In sheep and goats, Con A had no effect on lymphocytes from 50%, stimulated BLV production in 43%, and inhibited BLV production in 7%. These results indicated that lymphocytes should be cultured with and without Con A to identify every BLV-infected animal.

Animals↗
PubMed1977

B-lymphocytes and T-lymphocytes in three types of bovine lymphosarcoma.

Lymphoid cells of peripheral blood, lymph nodes, and thymus from clinically normal cattle, cattle infected with bovine leukemia virus (BLV), and cattle with lymphosarcoma were characterized for T- and B-cell surface markers. B-cells were detected by the erythrocyte-antibody-complement (EAC) rosette test and the surface immunoglobulin (sig) immunofluorescence assay. Peripheral blood from BLV-infected cattle had a higher than normal percentage of B-cells by both EAC rosette and sig immunofluorescence assays. Lymphoid cells from tumorous lymph nodes of cattle with the adult type of lymphosarcoma had a higher than normal percentage of sig-bearing cells, but in the same cell preparation the EAC rosette-positive cells were fewer than sig-positive cells. T-cells were detected by the erythrocyte rosette test. The percentage of T-cells by this test in lymph nodes of adult type lymphosarcoma was lower than that in normal cattle. A distinctly lower than normal percentage of lymphocytes could be characterized as either B- or T-cells in lymph nodes thymus, and peripheral blood from the calf type and thymic type of lymphosarcoma.

Animals↗
PubMed1977

Tumor-associated antigen in bovine and ovine lymphosarcoma.

Specific tumor-associated antigens were found on the membrane and in the cytoplasm of lymph node cells and peripheral blood lymphocytes (PBL) from cattle and sheep with lymphosarcoma by immunofluorescence tests. Materials from 15 cattle with the adult form of lymphosarcoma were examined. Cytoplasmic antigen was detected in fixed tumor cells from all 15 cases and in PBL from 9 cases tested. Membrane antigen was detected in living cells from 10 of the cases tested. In 3 calf-type cases, cytoplasmic antigen was found in a few (1 to 3%) of the tumor cells, while 1% of the cells from 2 thymic cases had cytoplasmic tumor antigen. In 15 cattle infected with bovine leukemia virus (BLV) but with no evidence of tumor, PBL from 3 cattle had the tumor-associated antigen in the cytoplasm. Negative results were obtained with similar tests done with 9 normal cattle that had no detectable BLV or BLV antibody. Cells from tumors induced with BLV in 5 sheep also had cytoplasmic antigen and membrane tumor-associated antigen. Tumor-associated antigen was found in PBL from 1 or 7 BLV-infected sheep with no clinical evidence of tumor. Similar tests were negative on 4 normal sheep.

Animals↗