PubMed Health⌕ Search

Biomedical subjects

K Kline

Publications and source records attributed to K Kline.

At least 55 records · Page 3Linked to original sources
PubMed1985

Perception of orientation of motion as affected by change in divergence of texture, change in size, and in velocity.

When there is relative motion between an observer and a textured surface such as the ground, motion-related visual information is available about the orientation of the surface through vergence of the paths of the elements of the texture, change in their sizes and in their velocities. This experiment determined the perceptual effectiveness of each variable in foveal and peripheral viewing for producing perceptions of three-dimensional motion. The three variables were electronically separated and displayed singly, in all possible pairs, and all together. Subjects communicated their perceptions of degree of perceived surface tilt at the top, bottom, and middle of the display for the eight different combinations of variables because, during pilot work perceived surface bendings were frequently noted where top, bottom, and middle appeared tilted to different extents. All three variables can lead to relatively reliable perceptions of perceived orientation of the plane of motion, with change in velocity being the most powerful determiner. Change in size was the weakest. Certain combinations can lead to perceptions of extreme warping and should be avoided in motion displays. Subjects consistently underestimate the amount of simulated tilt. Foveal viewing was more accurate than peripheral viewing but peripheral performance was adequately consistent as an input channel for some orientation tasks.

Depth Perception↗
PubMed1984

Molecular characterization of fetal antigens on red blood cells of chickens, Japanese quail, and quail-chicken hybrids.

The molecular nature of chicken fetal antigen (CFA) and quail fetal antigen (QFA) was studied on embryonic red blood cells (RBCs) of the chicken, the Japanese quail, and the quail-chicken hybrid. Specific immunoprecipitation of radiolabeled membrane proteins followed by electrophoretic separation and autoradiography were used to identify the protein molecules carrying these fetal antigens. CFA was found on molecules of 24, 50, 88, 99, 130, 170, and 220 kd (kilodaltons) in the chicken and hybrid and on molecules of 24, 50, 99, and 170 kd in the Japanese quail. Similarly, quail fetal antigen was associated with 24-, 50-, 99-, and 170-kd molecules in the quail and hybrid and was not detected in the chicken. Partial proteolytic digestion of the 50- and 170-kd molecules isolated from RBCs of all sources showed remarkably similar peptide patterns. Likewise, two-dimensional separation of the CFA-positive and QFA-positive 50-kd molecules from quail RBCs revealed a similar pattern of at least nine isomorphic variants. Sequential depletions of quail embryonic RBC extracts with either anti-CFA or anti-QFA followed by immune precipitation with the reciprocal antiserum suggested that most of the cell surface proteins carrying QFA also have CFA on the same molecules. It is suggested that specific glycosylations of a variety of distinct molecular weight proteins determines the antigenic phenotype characterized as "fetal antigens."

Animals↗
PubMed1984

Hematopoietic differentiation cell surface antigen switching in the bone marrow of different aged chickens.

Immune cytolysis and immunofluorescence were used to examine chicken fetal antigen CFA) and chicken adult antigen (CAA) expression on the differentiation/maturation series of definitive erythroid cells obtained from the bone marrow of different aged chickens. We found that erythroid cells undergo changes in CFA/CAA antigenic expression dependent on their differentiation/maturation stages as well as the developmental age of the chicken. All differentiation/maturation stages of erythroid cells in the bone marrow of 12 and 18-day-old embryos express CFA only. Erythroblasts obtained from 7-day post-hatched chickens express either CFA or CAA. All three CFA/CAA phenotypes (i.e., CFA, CAA, and CFA + CAA) are observed in subsequent maturation stages, but only the CFA + CAA phenotype is observed in mature erythroid cells in the bone marrow of 7-day post-hatched chickens. Erythroblasts from 62 day post-hatched chickens exhibit all three CFA/CAA phenotypes. Cells in the subsequent maturation stages express various CFA, CAA, or CFA + CAA phenotypes resulting in a majority of the mature erythrocytes expressing both CFA and CAA, and a small population of mature erythrocytes expressing CAA only. Erythroblasts from adult chickens express both CFA and CAA; however, CFA is lost during erythroid maturation resulting in mature erythrocytes which express CAA only. These studies indicate that both the erythroid differentiation/ maturation stage and the developmental age of the chicken influence CFA and CAA antigenic expression on erythroid cells undergoing cellular differentiation/maturation in the bone marrow.

Aging↗
PubMed1984

Immunochemical characterization of differentiation and age-related cell surface antigens expressed by chicken erythrocytes.

Hematopoietic-lymphoid membrane antigens that are related to cell differentiation and development, referred to as chicken fetal antigen (CFA) and chicken adult antigen (CAA) were immunochemically characterized; Mr 220,000; Mr 170,000; Mr 130,000; Mr 99,000; Mr 88,000; Mr 50,000; and Mr 24,000 CFA molecules are detected on embryonic RBC, and Mr 210,000; Mr 130,000; Mr 102,000; Mr 56,000; Mr 48,000; and Mr 43,000 CAA molecules are detected on adult RBC. Limited peptide mapping analyses showed all of the CFA and CAA molecules to be distinct entities. Both the Mr 50,000 CFA and the Mr 43,000 CAA molecules exhibited multiple isomorphic variants when analyzed by 2-dimensional electrophoresis. Analyses involving neuraminidase treatments and limited peptide mapping showed the Mr 50,000 CFA isomorphic variants to be chemically identical with the isoelectric point variations being due to sialic acid differences. In addition to multiple isomorphic variants, the molecular weight and charge differences of which were diminished by neuraminidase treatments, the Mr 43,000 CAA molecules exhibited a doublet pattern suggesting that the polyclonal antisera may be detecting chicken major histocompatibility complex products. Analyses of the Mr 50,000 CFA molecules immunoprecipitated with monoclonal antibody 190-4 confirmed that the monoclonal antibody recognizes a serological subset of the Mr 50,000 CFA molecules but showed that it did not recognize a unique molecularly detectable subset among the 18 isomorphic variants discernable by 2-dimensional electrophoretic analyses. Cocapping analyses with splenic lymphocytes showed CFA and CAA to occur as distinct membrane entities on lymphocytes.

Animals↗
PubMed1984

Suppression of Con A mitogen-induced proliferation of normal spleen cells by macrophages from chickens with hereditary muscular dystrophy.

Spleen cells from chickens with hereditary muscular dystrophy (MD) give low blastogenic responses to the T cell mitogen concanavalin A (Con A) while exhibiting normal mitogen stimulated blastogenic responses to the T cell mitogen phytohemagglutinin (PHA). The addition of MD spleen cells to normal spleen cells caused a marked suppression of the Con A response of the normal cells while not affecting the PHA response of the normal cells. The suppressive activity by the MD spleen cells requires viable cells and is contact mediated. The suppressive activity is attributed to the presence in MD spleens of a population of suppressor cells with characteristics typical of macrophages. The suppressor cell activity was not removable by complement-mediated lysis using anti-T or anti-B sera, but it was reversible by treatment with carrageenan or carbonyl iron magnet, by passage through a Sephadex G-10 column, and by adherence to plastic petri dishes or glass beads. MD spleen cells depleted of the suppressor cell population remained unable to respond to Con A.

Animals↗
PubMed1982

Monoclonal antibody to chicken fetal antigens on normal erythroid cells and hematopoietic-lymphoid tumor cell lines.

Hybridoma cell lines secreting antibodies to chicken fetal antigens (CFAs) were generated by the fusion of mouse P3X63Ag8 myeloma cells with spleen cells from a mouse immunized with intact SC chicken strain one-day-hatched red blood cells. Immunodepletion studies show monoclonal anti-CFA to be detecting a subset of the Mr 50,000 CFA molecules recognized by polyclonal anti-CFA. Monoclonal anti-CFA is erythroid specific against in vivo-derived hematopoietic-lymphoid cells. Exceptions to the erythroid specificity of monoclonal anti-CFA include failure to react with avian erythroblastosis virus-transformed erythroid cells both before and after butyric acid-induced differentiation and reactions with reticuloendotheliosis virus-transformed immature lymphoid cells and chicken embryo cells. Immunofluorescence and 125I binding analyses utilizing monoclonal anti-CFA show reticuloendotheliosis virus cells to possess high levels of CFA even though the CFA determinant does not appear to be a 125I-labeled immunoprecipitable Mr 50,000 molecule. The unique property of monoclonal anti-CFA that permits it to distinguish among surface membrane antigens of normal and neoplastic cells of the same lineage makes it an important tool for future investigations of normal and abnormal cell differentiation.

Animals↗
PubMed1982

Demonstration of a cellular defect in the thymus of hereditary muscular dystrophic chickens.

The thymuses of different aged hereditary muscular-dystrophic (MD) chickens were examined for abnormalities. Histochemical analyses showed a normal cellular profile. Thymic myoid cells were normal as to numbers, size, distribution, and metabolic status. The thymuses of MD chickens, however, exhibited two abnormalities not found in age and sex-matched normal controls. The thymus lobes were smaller in size and weighed less than the thymus lobes from controls, and the thymus cells from MD chickens gave reduced Con A and elevated PHA-T-cell mitogen-mediated blastogenic responses.

Animals↗
PubMed1982

Chicken fetal and adult antigen expression on erythroleukemia cells before and after induced differentiation.

Avian erythroblastosis virus strain R (AEV)-transformed, cloned erythroleukemia cells from three different ages of SC strain chickens were analyzed before and after differentiation induced by 1.0 mM butyric acid for expression of chicken fetal antigens (CFAs) and chicken adult antigens (CAAs) and for hemoglobin expression. Immunofluorescent analyses show the loss of individual CFA determinants from erythroleukemia cells with induced differentiation, although there appeared to be no correlation between CFA loss and onset of hemoglobin production. Erythroleukemia cells were examined by cell surface labeling followed by immunoprecipitation with antisera specific to CFAs and CAAs. Erythroleukemia cells expressed CFAs and CAAs on their membranes that are not reported to be expressed by the target cell of AEV. The expression of CAAs and the enhanced expression of CFAs by erythroleukemia cells may be due to limited cellular differentiation, alterations in regulatory controls of genes coding for CFAs and CAAs, or increased levels of production of previously undetected CFAs and CAAs following AEV transformation. Control and induced erythroleukemia cells expressed CFAs and CAAs that differed both quantitatively and qualitatively from normal erythroid cells. Molecular weight variations of CFAs and CAAs observed in the erythroleukemia cells may represent glycolyzation differences between AEV-transformed cells and normal erythroid cells.

Alpharetrovirus↗
PubMed1981

Chicken fetal antigen: example of an antigenically complex oncodevelopmental membrane glycoprotein.

CFA is a complex onco-developmental membrane marker system that is being investigated at the cellular, molecular, genetic and functional levels. CFA appears to be a family of genetically-determined carbohydrate side chains attached to a membrane-bound polypeptide chain. Unique combinations of the thirteen serologically detectable CFA determinants are expressed on erythroid and lymphoid cells of all avian species tested. Whether or not CFA determinants are hematopoietic specific markers remains to be established. The CFA determinants are proving to be useful membrane markers for the study of normal as well as neoplastic hematopoietic cellular differentiation. The probability that CFA determinants are differentiation-stage-specific markers for cells of both the erythroid and lymphoid series coupled with the observation that one of the CFA determinants acts as a cell membrane binding site for an arbovirus makes this antigen system a valuable tool for studying the cellular differentiation blockage hypothesis of neoplasia.

Aging↗
PubMed1980

Serum IgG levels in the Storrs strain of hereditary muscular dystrophic chickens.

IgG levels in sera of Storrs hereditary muscular dystrophic chickens were investigated. IgG levels in age-matched Storrs muscular dystrophic chickens varied, depending on the geographical location where the chickens were reared. IgG levels from muscular dystrophic chickens at varying ages of development were approximately 30% less than age-matched control values. Genetic analyses of F1 hybrid, F2 progeny, and testcross progeny showed the reduced IgG levels in the Storrs strain of muscular dystrophic chickens not to be correlated with the autosomal recessive muscular dystrophic trait, the degree of muscle destruction, nor with an autosomal recessive T cell defect. The studies reported here suggest (1) that the reduced IgG levels in the Storrs strains of muscular dystrophic chickens are due to strain differences and (2) that the mode of inheritance of serum IgG levels in the Storrs strain of muscular dystrophic chickens is polygenic.

Age Factors↗
PubMed1980

Developmental profile of chicken splenic lymphocyte responsiveness to Con A and PHA and studies on chicken splenic and bone marrow cells capable of inhibiting mitogen-stimulated blastogenic responses of adult splenic lymphocytes.

Embryonic and newly hatched chicken splenic lymphocytes were analyzed for their ability to respond to 2 mitogens, Con A and PHA. Acquisitions of the ability to respond to both mitogens began at hatch and responses to both mitogens reached normal adult blastogenic response levels by 11 days post-hatch. Splenic lymphocytes in the developing embryo and newly hatched chicken were found to be capable of inhibiting the Con A- and PHA-mediated blastogenic responses of both syngeneic and allogeneic adult splenic lymphocytes. The ability to suppress adult responses was first observed on E12, reached a maximum of suppressive ability on E18, and the suppressive ability was gradually lost with development such that no suppressive ability was exhibited after H11. Ability to suppress adult splenic lymphocyte proliferation to mitogens was found to not be a unique property of splenic lymphocytes but was also exhibited by bone marrow cells. The ability of bone marrow cells to suppress adult splenic lymphocyte proliferation to Con A and PHA gradually decreased with chicken aging but the suppressive ability was never lost and adult bone marrow cells were found to exhibit significant degrees of suppressive ability. The mechanism of suppression by the 1-day-hatched splenic lymphocytes was found to be cell-to-cell contact mediated and did not require any newly synthesized H1 splenic products, since x-ray killed cells were able to suppress as well as live cells.

Aging↗
PubMed1977

Expression of serum proteins in the developing chick embryo.

1. Sera from different embryonic stages of development and adult chickens were examined for embryonic-adult differences. 2. An antisera prepared in rabbits to 14 day embryonic chick sera revealed an antigen present in the early stages of embryonic development. The antigen reached a peak on day 14 and was not detectable 5 days post hatching. 3. Gel filtration studies in conjunction with immunodiffusion studies revealed the serum antigen to be in the 160,000 mol wt range. 4. Immunoelectrophoretic analyses of embryonic and adult sera revealed the sera components to increase in quantity and in numbers with development. The serum immunoelectrophoretic profile of newly hatch chick serum closely resembled sera from adult chickens. 5. Polyacrylamide gel electrophoretic comparisons of the sera of the developing chicks and the adult chickens revealed proteins specific to certain developmental stages as well as proteins specific to the adult serum. Qualitative and quantitative serum protein differences were found.

Animals↗
PubMed1977

Utilization of a differential hemoglobin elution procedure as a rapid assay for identification of embryonic and adult chicken red blood cells.

1. A hemoglobin elution-staining procedure has been developed for distinguishing embryonic chick red blood cells from adult chicken red blood cells. 2. Adult hemoglobin is eluted from red blood cells with 1.9 M potassium phosphate buffer, pH 7.2; whereas, embryonic hemoglobin is retained within the cells and gives positive staining with erythrosin B. 3. The hemoglobin elution-staining pattern during development can be correlated with two embryonic hemoglobins as detected by polyacrylamide gel electrophoresis. 4. The series of red blood cells staining with erythrosin B correspond to the primary erythrocyte series suggesting that hemoglobin expression during development is correlated with different cell populations.

Aging↗