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T Pearson

Publications and source records attributed to T Pearson.

67 records · Page 4Linked to original sources
PubMed1978

Measurement of H-2 antigen and immunogenicity of methylcholanthrene-induced murine sarcomas.

For each of a set of 11 methylcholanthrene-induced sarcomas of B10 mice, we measured the amount of H-2 antigen by absorption of a specific antiserum, and the strength of the tumour-specific transplantation antigen by a transplantation assay, to see whether they are correlated. No obvious correlation was seen. We showed that cell suspensions of tumours taken directly from the animal are contaminated by host cells which make a substantial contribution in H-2 assays. Since this contamination was lost after several passages in vitro, the amount of H-2 on tumour cells was assayed only after such passages.

Animals↗
PubMed1977

A myeloma hybrid producing antibody specific for an allotypic determinant on "IgD-like" molecules of the mouse.

A hybrid cell line was produced by fusing a mouse myeloma line with spleen cells from BALB/c mice immunized with B10 cells. The hybrid line grew in tissue culture and in syngeneic mice and produced IgM antibody specific for "IgD-like" molecules of mice with the Igb haplotype. The concentration of monoclonal antibody in the serum of tumor-bearing animals reached about 2 mg/ml and gave cytotoxic titers of up to 1:800 000. The derivation of the line, some properties of the antibody secreted and the nature of its antigenic target are described.

Animals↗
PubMed1977

Fusion of T and B cells.

Hybrid cells were prepared by fusin an immunoglobulin-secreting mouse myeloma lin e (B cell) with an allogenic T-cell lymphoma which expresses the surface antigen Thy 1. The resulting hybrids expressed H2 antigens of both parental cells and secreted the immunoblobulin of the myeloma parent but did not express the Thy 1 antigen of the lymphoma parent. Twenty-one hybrids were formed from fusion of the same myeloma line with TNP-SRBC-primed spleen cells. Most of the hybrid lines exhibited characteristics expected for the fusion of the myeloma to B lymphocytes. No hybrids between the myeloma line and spleen T cells were identified as none of the hybrids expressed the T-cell-specific antigen Thy 1. We discuss possible reasons for failure to produce hybrids with T-cell characteristics in these types of fusion.

Animals↗
PubMed1976

The effect of antigen suicide on numbers of cells binding defined antigenic determinants.

Lymph node cells from guinea pigs immunized to oxidized ferredoxin (O-Fd) were treated in an antigen suicide procedure designed to inactivate lymphocytes binding the haptenic peptide determinants of the ferredoxin molecule. O-Fd-induced DNA synthesis and cells binding either peptide determinant were examined both before and after allowing suicide. The proliferative response to O-Fd and the number of determinant-binding cells were specifically and markedly decreased after antigen suicide.

Animals↗
PubMed1976

Pneumonitis due to Corynebacterium equi.

Corynebacterium equi, a known cause of pneumonitis in foals, calves, and swine, was isolated from the sputum and bronchial washings of a child with pneumonitis and leukemia. Clinical improvement followed the administration of chloramphenicol, and cultures of sputum specimens were sterile until relapse occurred after antibiotic therapy was terminated. Cure was achieved with a second course of chloramphenicol therapy. Corynebacterium equi was not isolated from 1,181 samples of sputum from other immunosuppressed children with cancer.

Adolescent↗
PubMed1975

The effect of specific cell inactivation on the cellular immune response to ferredoxin peptides.

Previous studies using synthetic immunogenic molecules containing two haptenic peptides (ther NH2-terminal heptapeptide and the COOH-terminal pentapeptide of oxidized ferredoxin (O-Fd) from C. pasteurianum) have shown that both peptides individually are capable of initiating lymphocyte transformation and inhibiting migration in populations of lymphocytes from O-Fd-sensitized guinea pigs. While migration inhibition could readily be stimulated by single haptenic peptides, lymphocyte treasformation appeared to be more easily induced by molecules containing two or more haptenic peptides (these could be identical or different) (Kelly, B., Levy, J.G. and Hull, D., Eur. J. Immunol., 1973. 3:574). If lymphocyte transformation is a T cell-mediated phenomenon, these observations indicate the possibility of T cell-T cell interaction. The two haptenic peptides (designated "N" and "C") were synthesized and conjugated to succinylated bovine serum albumin (S-BSA), forming the conjugates N-S-BSA and C-S-BSA, respectively. These conjugates were labeled to high specific activity with 125iodine and were used in an "antigen suicide" procedure to treat guinea pig lymph node cell preparations previously sensitized to O-Fd and keyhole limpet hemocyanin (KLH). Cell populations exposed to either 125I-labeled C-S-BCA demonstrated decreased lymphocyte transformation in the presence of O-Fd but not in the presence of KLH. These results indicate specific cell inactivation by the radioactive peptide conjugates of those cells responsible for initiating cell transformation. Experiments performed by mixing 125I-labeled N-S-BSA-treated cells with 125I-labeled C-S-BSA-treated cells were successful in partially restoring the response to O-Fd and suggest possible synergy between N and C determinant binding cells in the cellular immune response to O-Fd. Evidence from B cell depletion studies suggests that this is a T cell-T cell interaction.

Animals↗
PubMedDate not supplied

Plasticity of purine release during cerebral ischemia: clinical implications?

Adenosine is a powerful modulator of neuronal function in the mammalian central nervous system. During a variety of insults to the brain, adenosine is released in large quantities and exerts a neuroprotective influence largely via the A(1) receptor, which inhibits glutamate release and neuronal activity. Using novel enzyme-based adenosine sensors, which allow high spatial and temporal resolution recordings of adenosine release in real time, we have investigated the release of adenosine during hypoxia/ischemia in the in vitro hippocampus. Our data reveal that during the early stages of hypoxia adenosine is likely released per se and not as a precursor such as cAMP or an adenine nucleotide. In addition, repeated hypoxia results in reduced production of extracellular adenosine and this may underlie the increased vulnerability of the mammalian brain to repetitive or secondary hypoxia/ischemia.

Adenosine↗
PubMedDate not supplied

Putting medical practice guidelines into practice: the cholesterol model.

As more and more medical practice guidelines are developed in the United States, commensurate evaluation efforts should assess their impact on professional practice and patient outcomes. We describe an ongoing research program designed to develop and test practice models for applying the 1988 Adult Treatment Panel Guidelines for the clinical management of high blood cholesterol. Four studies are evaluating different models to assist nonacademic community practices in the detection, evaluation, and treatment of high blood cholesterol. We have designed randomized controlled trials set in solo and small-group primary care practices of family or general practitioners and internists situated in rural, suburban, and urban settings. Patients include adult men and women who represent diverse socioeconomic and ethnic backgrounds. We are measuring rates of cholesterol screening; dietary and drug treatment and follow-up; changes in dietary intake and compliance with drug therapy; changes in quality of life and cost of intervention; and reduction in cholesterol level. Scheduled for completion in 1994, this program will provide insights into practical and effective methods of lipid management. It serves as a model for studying the application of health guidelines in the context of nonacademic primary care practices serving diverse patient populations.

Cholesterol↗
PubMedDate not supplied

Simultaneous pancreas kidney transplantation: initial experience of the Emory University transplant service.

The successful replacement of islet tissue by pancreas transplantation appears to be beneficial in the early course of those uremic diabetic recipients who receive a simultaneous renal transplant. The long-term advantages of SKP transplantation remain to be determined, however, current improvement in patient and graft survival following SPK and the difficulties thus far reported in islet cell transplantation have renewed clinical interests in SPK, PAK and PA transplantation. In our experience, pancreas transplantation has been a challenging technical, immunological and physiological endeavor which was well received by our patients despite the initial problems and complications we and they encountered. Notwithstanding extensive preparation, our team experienced a "learning curve" and we present many of the lessons we learned. This knowledge has aided our transplant team in the successful management and avoidance of these complications and other inherent problems associated with SKP transplantation in subsequent patients.

Anastomosis, Surgical↗