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D DeLuca

Publications and source records attributed to D DeLuca.

30 records · Page 2Linked to original sources

Lymphocyte-like cells of the tunicate, Pyura stolonifera: binding of lectins, morphological and functional studies.

In vitro investigations were carried out to determine whether lymphocyte-like (small round) cells of the tunicate Pyura stolonifera react to allogeneic cells and mitogens in a manner comparable to that of vertebrate immunocytes. The lymphocyte-like cells possessed receptors for concanavalin A, wheat germ agglutinin and soybean lectin as shown by binding of radioiodinated lectins in scintillation counting and autoradiographic assays. This binding did not induce mitogenesis. Mixtures of cells of P. stolonifera individuals taken from the same or distinct localities did not show enhanced DNA synthesis when assayed at time intervals ranging from 3 to 10 days. The small round cells of this and other tunicates are not completely similar to vertebrate lymphocytes in morphology. Our observations support the concept that these cells are not directly homologous to immunologically competent vertebrate lymphocytes, but may serve as haemopoietic stem cells as proposed by other (Endean, 1954; Freeman, 1970).

Animals

Validation of a laboratory play measure of child aggression.

The validity of laboratory play measures of aggression has been called into question. Critics have charged that laboratory findings on childhood aggression cannot be generalized to everyday aggression. In the present study, the validity of striking a Bobo clown as a measure of aggression was assessed by correlating the rate of this behavior with peer ratings, teaching ratings, and self-ratings of aggressiveness in a preschool. Laboratory aggression correlated significantly with both peer ratings, r = .76, p less than .01, and teacher ratings, r = .57, p less than .05, but not with self-ratings, r = .36. Laboratory aggression correlated more highly with aggression ratings for males (N = 9) than for females (N = 9), but not significantly so. The findings support the use of laboratory play as a valid measure of aggression in children.

Aggression

Phylogenetic origins of immune recognition: lymphocyte surface immunoglobulins in the goldfish, Carassius auratus.

Membrane immunoglobulin (Ig) of splenocytes and thymocytes of the goldfish, Carassius auratus, was demonstrated by indirect fluorescent-antibody techniques. Observations on shedding and resynthesis indicated that the thymocyte Ig was endogenously produced. The lymphocyte surface proteins were radioiodinated using the lactoperoxidase-catalyzed reaction, and the labeled Ig molecules were isolated by specific precipitation and analyzed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The IgM-like membrane Igs of splenocytes and thymocytes were shown to differ in their ease of solubilization with nonionic detergent, and in the sodium dodecyl sulfate/electrophoretic mobility of their heavy chains. The significance of these observations for the evolution of T-cell recognition is discussed.

Animals