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Biomedical subjects

B H Park

Publications and source records attributed to B H Park.

10 recordsLinked to original sources
PubMed1979

Biochemical basis of aroclor 1254 and pesticide toxicity in vitro. 1. Effects on intracellular ATP concentration.

Aroclor 1254 and op'-DDT inhibit lymphocyte mitogenic response to PHA. We use petri dish purified lymphocytes for studying the biochemical basis of chemical toxicity. Aroclor 1254 and DDT decrease lymphocyte intracellular ATP concentration. The inhibitory effect on ATP production is due to the suppression of mitochondrial respiration as judged by decreased oxygen consumption. Lymphocyte glycolysis measured by lactate production is not inhibited by Aroclor 1254 to any significant extent. ATP is required for various biosynthetic reactions following mitogenic stimulation. The inhibition of mitochondrial respiration which leads to decreased ATP concentration may be responsible for Aroclor inhibition of lymphocyte mitogenic response to PHA.

Adenosine Triphosphate↗
PubMed1979

Effects of pesticides on human leukocyte functions.

Aroclor 1254 and twelve pesticides of different chemical classes were tested for their in vitro effects on lymphocyte mitogenic responses to PHA, rosette formation with sheep red blood cells (E-rosette) and neutrophil chemotaxis. By using a diluted whole blood culture, butoxide at 10 micrometers inhibit lymphocyte mitogenic response to PHA by 26%. Inhibition by other pesticides were less than 20% (5--20(). Higher degrees of inhibition were observed if the lymphocytes were pretreated with pesticides in the absence of serum: pp-DDT inhibited by 73% trithion by 50% and benzylthiocyanate by 30%. E-rosette formation was less inhibited by these pesticides except DDT, which inhibited the E-rosette formation by 50% at 10(-4)M. Only methyl parathion was found to have some inhibitory effects on neutrophil chemotaxis. These results indicate that insecticides may have direct effects on the leukocyte function and that the presence of serum may alter the interaction of insecticides and leukocyte membranes.

Chemotaxis, Leukocyte↗
PubMed1978

An improved micro-method for enumeration of human B-cell rosettes with mouse red blood cells.

A micro-method for enumerating B-lymphocytes in human peripheral blood is described, using formation of rosettes with mouse red blood cells as a B-cell marker. The optimal conditions for the enumeration of mouse red cell rosette forming cells have been defined. By this method, it was possible to utilize less than 1ml of peripheral blood (venous or capillary) for simultaneous enumeration of both T-cell and B-cell rosettes. Our study of human lymphoid cell lines, thymic cells, lymphocytes from agammaglobulinemia, and severe combined immunodeficiency has provided additional evidence that lymphocyte rosetting with mouse red blood cells represent B-lymphocytes.

Animals↗
PubMed1975

Immunologic reconstitution in man--present status.

Recent advances in immunobiology have shed new light on our understanding of the essential role of immunity as it relates to body economy. Immunity, once thought to be the primary defense mechanism against microbial infection, appears to have a much broader function--recognition and elimination of foreign bodies and preservation of the integrity of the individual. As our understanding of the pathophysiology of the immune system became more clear, immunologic reconstitution emerged as a new, promising mode of treatment for a variety of diseases with immunodeficiency. Bone marrow transplantation, thymus transplanation, transfer factor therapy, infusion of leukocytes, BCG vaccination, and other specific or nonspecific immunostimulants have been tried, with dramatic beneficial results in some instances. Although still in its infant stage, this form of treatment appears to have great potential and wide application in the prevention and treatment, not only of primary immunodeficiency, but also of many other diseases such as cancer, the so-called autoimmune diseases, and even aging.

Animals↗
PubMed1975

Compatible bone marrow transplantation and immunologic reconstitution of combined immunodeficiency disease.

To date, bone marrow transplantation affords the only successful means of achieving full immunologic reconstitution of patients with severe combined immunodeficiency disease (SCID). We have achieved immunologic reconstitution in 6 of 7 SCID patients using marrow transplants from compatible sib donors. One child died of Pneumocystis carinii pneumonia following early immunologic reconstitution. A second child died of sepsis without evidence of engraftment, despite 3 marrow grafts, and a third died unexpectedly from massive aspiration pneumonia following complete immunologic reconstititon. Thus, in 4 of 7 children with SCID full and long-lasting immunologic reconstitution has been achieved by transplantation of marrow from matched sib donors. From these initial efforts, much has been learned, and it is clear that several factors, some of which remain poorly understood, may influence the outcome of marrow grafting. However, despite the difficulties encountered, bone marrow transplantation continues to hold real promise for correction of this otherwise fatal disease.

Antibody Formation↗
PubMedDate not supplied

Leprosy XII. Quantitative analysis of thymus-derived lymphocyte response to phytohemagglutinin in leprosy.

The immune status of various leprosy patients was evaluated by using a micromethod to evaluate lymphocyte responses to phytohemagglutinin (PHA). In our study, whole blood was used and the degree of response to PHA stimulation was expressed in terms of unit volume of blood. A markedly decreased response to PHA stimulation was noted in patients with active lepromatous leprosy. Patients with active lepromatous leprosy who have been proved drug (DDS) resistant showed less response than did those of drug sensitive patients with active lepromatous disease, while the patients with active lepromatous leprosy complicated by erythema nodosum leprosum (ENL) showed higher response than did those of patients with no complicated ENL. Comparing the results obtained to those obtained using other methods for T cell analysis indicates that these results reflect the number of T lymphocytes in the leprosy patient. Thus, this simple method is of value in assaying the presence and responses of T lymphocytes in the leprosy patient.

Dapsone↗