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Biomedical subjects

T C Morris

Publications and source records attributed to T C Morris.

88 records · Page 5Linked to original sources
PubMed1980

Inhibition of normal human granulopoiesis in vitro by non-B non-T lymphocytes.

Normal non-adherent mononuclear cells were shown to inhibit colony formation by normal human marrow cells cultured for 7 d in semi-solid agar. Inhibition was the same using cells from the marrow donor or from an unrelated normal subject, and was shown to be dose-dependent over the range of 4 X 10(5) to 6 X 10(3) mononuclear cells per 1 X 10(5) marrow cells plated. Inhibition was not seen in 14 d cultures, and it is postulated that colony-forming cells sensitive to lymphocyte inhibition belonged to the population known to give rise to colonies after 7 d in culture. Cell fractionation studies showed that inhibition was due to non-B non-T lymphocytes, purified B cells or T cells being neither inhibitory nor stimulatory. Inhibition was only shown with intact viable lymphocytes and it was not possible to extract inhibitory activity from the cells, or to produce inhibition by media conditioned by lymphocytes. The effect was apparently due to a direct action on colony-forming cells in the marrow and was not due to inhibition of colony stimulating activity (CSA) production, or to absorption or inactivation of CSA. These results emphasize the need to include appropriate controls when looking for possible cell-mediated inhibitors in disease states, particularly when 7 d cultures are used.

Cells, Cultured↗
PubMed1980

Lysosomal enzyme activities in a case of T-cell chronic lymphocytic leukaemia.

This study indicated that (i) high levels of N-acetyl-beta-glucosaminidase and beta-glucuronidase could be demonstrated cytochemically in T-CLL lymphocytes, and (ii), the biochemical activities of both enzymes were significantly increased in T-CLL lymphocytes compared with B-CLL lymphocytes. It would appear that the biochemical and cytochemical determination of these lysosomal enzyme activities offers an additional means of distinguishing T-CLL and B-CLL lymphocytes.

Acetylglucosaminidase↗
PubMed1979

Bone marrow necrosis and extramedullary myeloid tumour necrosis in aggressive chronic myeloid leukaemia.

A patient with chronic myeloid leukaemia who developed widespread bone marrow necrosis associated wtih evolution of a new cell clone and with aggressive behaviour of the myeloid tumour in extramedullary sites is described. Cell necrosis in extramedullary tumours was also present; the sharp demarcation between zones of necrotic cells and intact cells and the histological evidence of vascular invasion by tumour cells suggest a vascular basis for cell necrosis.

Bone Marrow Diseases↗
PubMed1978

Inhibitor of in-vitro granulopoiesis in plasma of patients with renal failure.

Plasmas from 31 patients with moderately severe to severe renal failure inhibited granulopoietic colony formation in human marrow in vitro. The inhibitory activity could not be removed by in-vitro dialysis but was present in an ultrafiltered fraction of molecular weight less than 25 000 daltons. It inhibited the production of colony-stimulating activity (C.S.A.) by leucocytes in the culture system but had little or no effect on preformed C.S.A. or on the granulopoietic colony-forming cell itself. The level of plasma inhibitory activity correlated with the degree of azotaemia but not with the neutrophil or monocyte counts. Despite the potency with which granulopoiesis was inhibited in vitro, none of the patients was severely neutropenic, and only 4 had mild neutropenia (neutrophil count 1.5--2.1 x 10(9)/1).

Bone Marrow↗
PubMed1977

Changes in granulopoiesis detected by in vitro colony formation in acute lymphatic leukaemia.

Patients with acute lymphatic leukaemia (ALL) could be divided into two groups at diagnosis--those whose peripheral blood and/or bone marrow exhibited in vitro colony formation and those in whom it did not, but this finding did not appear to correlate with any clinical or haematological parameter, or with prognosis. The colonly-forming potential of patients with ALL in their first full remission, early relapse or second remission did not deviate significantly from previously established normal values, but the colony-forming potential of patients in early remission was very significantly reduced. No loss of colony-forming potential of normal marrow cells was noted when they were cultured with cells from patients with ALL.

Adolescent↗
PubMed1975

Inhibition of normal human in vitro colony forming cells by cells from leukaemic patients.

Co-culture in agar of normal bone marrow cells from different individuals gave granulocyte macrophage colony counts that were expected from counts made when the marrows were cultured separately. Co-culture of normal marrow with normal peripheral blood leucocytes (which did not themselves give rise to colonies) caused inhibition of colony growth only when the ratio of peripheral blood to bone marrow cells was of the order of 4 : 1. Peripheral blood or bone marrow cells from 7 of 9 patients with acute myelomonocytic leukaemia, which did not give rise to colonies, caused a marked reduction in the number of colonies obtained from normal marrow cells when cultured with them. This inhibitory effect of leukaemic cells was found when ratios of leukaemic to normal cells were as low as 1 : 4. Additional evidence that the inhibition of normal colony formation was related to the leukaemic process was obtained from follow-up studies on one of the patients whose cells lost the capacity to inhibit normal colony formation during remission and became inhibitory again on relapse.

Adolescent↗
PubMed1975

Reactivation of scabies rash by methotrexate.

A 13-year-old female was on maintenance therapy for acute lymphoblastic leukemia. On three occasions she received methotrexate orally and each time this was associated with reactivation of scabies rash. The mechanisms for this phenomenon are discussed.

Adolescent↗
PubMed1974

Characteristics of colony growth from normal human bone marrow.

The number of granulocyte/macrophage colonies grown in vitro from bone marrow cells obtained from 90 rib segments and 30 ;normal' bone marrow aspirates was found to be highly variable. Considerable variation was also noted in the relationship between colony number and the number of cells cultured in both groups. The aspirate group was found to have a significantly greater ability to form colonies without the addition of colony-stimulating factor to the culture medium at low cell concentrations.

Biopsy↗
PubMedDate not supplied

Increase in fast hemoglobin concentration after incubation with acetaldehyde detected by an electrophoretic method.

Incubation of acetaldehyde with hemoglobin has been shown by chromatographic methods to result in an increase in fast hemoglobin. We have studied this increase in fast hemoglobin concentration by a gel electrophoretic method. Increases in fast hemoglobin concentration are detected following incubation with concentrations of 100 microM acetaldehyde and no further increase in yield occurs with concentrations greater than 7 mM acetaldehyde. The reaction is complete within 5 hr and the product is stable with a half-life of greater than 12 days.

Acetaldehyde↗