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B D Clarkson

Publications and source records attributed to B D Clarkson.

At least 145 records · Page 8Linked to original sources
PubMed1978

Rapid hypotonic method for flow cytofluorometry of monolayer cell cultures. Some pitfalls in staining and data analysis.

The rapid hypotonic staining procedure developed by Krishan for DNA determinations by flow cytofluorometry has been proven accurate for in vivo cell samples and for cell lines growing in suspension culture. We show that the unmodified procedure may produce distorted DNA histograms when used for staining cells growing in monolayer cultures, however. To eliminate these distortions, it was necessary to avoid the use of trypsin by staining the attached cells directly, using a hypotonic fluorochrome solution to which nonionic detergent was added. Two sublines of HeLa S3 cells are shown to exhibit major differences in their staining characteristics. By using our revised staining procedure, the two sublines appear to produce very satisfactory DNA histograms. However, in only one subline does the S phase fraction calculated from the histograms agree with the autoradiographical labeling index. Mitotic cells remain intact under these staining conditions, and the principal observed effect of nonionic detergents in this case is to decrease the coefficient of variation of fluorescence intensity.

Cells, Cultured↗
PubMed1978

Evidence for distinct lymphocytic and monocytic populations in a patient with terminal transferase--positive acute leukemia.

Two distinct cell populations with lymphoblastic and monocytic characteristics were separated and characterized by multiple cell markers in a patient with terminal transferase-positive acute acute leukemia. The clinical course and sequential cell marker studies were consistent with the interpretation of a defect at the level of a common stem cell giving rise to a terminal transferase--positive lymphoblastic cell population at diagnosis and, following initial therapy, a terminal transferase--negative monocytic population.

Adult↗
PubMed1977

Relationship of a T-lymphocyte marker to phase of cell cycle and morphology of leukemic cells.

Spontaneous rosette formation with sheep erythrocytes (SRBC) was studied in the peripheral blood and bone marrow lymphoid cells from a patient whose leukemic cells appeared to be T-lymphocytes. Simultaneous morphological examination of the peripheral blood white cells indicated that they consisted of 21% lymphoblast; 26% prolymphocytes and 48% mature lymphocytes. The distribution of bone marrow cells within the cell cycle was determined by flow microfluorometry and 7 hours after treatment with vincristine consisted of 69% in G1, 21% in S, and 9% in mitosis. Since virtually all the cells both in marrow and blood formed rosettes with SRBC this implies that the expression of this T cell marker is independent both of the morphological appearance of these cells and their position within the cell cycle.

Adult↗
PubMed1977

Detection of antibody to autologous human leukemia cells by immune adherence assays.

The sera of 21 adult patients with acute leukemia were studied for the presence of antibody reacting with surface antigens of autologous leukemia cells. Sequential serum samples were obtained from patients and were tested on cryopreserved leukemia cells in immune adherence assays. Three patients showed autologous serum reactivity and the serum of one of them was analyzed in detail. This antibody reacted with autologous acute lymphocytic leukemia cells but not with autologous cells obtained from peripheral blood, bone marrow, or spleen during clinical remission. In absorption tests, the antigen could not be detected on normal autologous or allogeneic blood lymphocytes, lymphoblastoid lines of T- or B-cell origin, or cells infected with simian sarcoma virus, baboon C-type virus, or Mason-Pfizer virus. Leukemia cells from two other patients with acute lymphocytic leukemia and one patient with acute nonlymphocytic leukemia absorbed specific reactivity. These studies indicate that certain acute leukemia cells express a common antigen that elicits a humoral immune response in the autologous host.

Acute Disease↗
PubMed1976

Acute lymphoblastic leukemia in adults and children. Differences in response with similar therapeutic regimens.

Twenty-three adult patients (ages greater than 15 years) and 75 children with acute lymphoblastic leukemia were treated with similar intensive, sequential cytotoxic protocols (L-2). The adult patients have lower remission rate (78%) than the children (98%). The duration of remission and the length of survival are also shorter in adults. The incidence of central nervous system (CNS) relapse in adults (27.7%) is higher than in children (7.1%) suggesting that prolonged prophylactic intrathecal methotrexate as given to the children is more effective than the schedule used for adults where intrathecal methotrexate was given only in the first 2 months of therapy. The low incidence of CNS involvement in children on the L-2 protocol compares favorably with other series reported using a combination of cranial irradiation and intrathecal methotrexate. In both adults and children there seemed to be a higher incidence of CNS involvement in patients with initial white blood cell counts greater than 25,000 cells/mm3.

Adolescent↗
PubMed1976

The role of bone marrow aspiration and biopsy in detecting marrow involvement by nonhematologic malignancies.

A review of the records of the Memorial Sloan-Kettering Cancer Center identified 291 adult patients with nonhematologic malignancies who had undergone simultaneous bone marrow aspiration and biopsy from the same anatomic site. In 236 cases both samples were negative for tumor whereas in 39 both were positive. The biopsy was positive in three patients with a negative aspirate whereas in three others to aspirate was positive with a negative biopsy. The higher rate of tumor detection on aspirate in comparison with previous reports may be due to a thorough initial screening provided by technologists. Both aspiration and biopsy appear to be indicated for full evaluation of bone marrow in cancer patients.

Adult↗
PubMed1976

Flow cytofluorometric analysis of cell cycle distributions using propidium iodide. Properties of the method and mathematical analysis of the data.

In order to better characterize the new rapid staining method for flow cytofluorometry proposed by Krishan, we have tested its stability and several other properties, and have carried out a quantitative comparison of the fluorescence histograms obtained using propidium iodide or the acriflavine-Feulgen staining procedure. Using a human hematopoietic cell line in the logarithmic phase of growth, and analyzing the data by means of a mathematical method we have devised, we found that the fluorescence intentsity of cells stained with propidium iodide remains stable for at least 48 h; it is insensitive to dye concentration between 0.025 and 0.10 mg/ml (37-150 muM); it is not affected by incubation with ribonuclease before staining; propidium iodide in 0.1% sodium citrate remains stable for at least 20 days; and quantitative estimates of the fractions of cells in the different phases of the cell cycle are in good agreement with those obtained from acriflavine-Feulgen staining and from autoradiography after pulse labeling with tritiated thymidine. We conclude that this method is useful for the measurement of relative DNA content by flow cytofluorometry, although modifications in the technique are necessary for some cell types which grow in monolayers.

Acriflavine↗
PubMed1976

Eight-drug combination chemotherapy (MOPP and ABDV) and local radiotherapy for advanced Hodgkin's Disease.

Thirty-seven patients with advanced Hodgkin's disease have been treated for greater than or equal to 3 months with a protocol consisting of alternate monthly courses of MOPP (mechlorethamine, Oncovin [vincristine], procarbazine, and prednisone) and ABDV (adriamycin, bleomycin, DTIC, and vinblastine) with local radiotherapy (RT) to areas of originally bulky disease. This therapy produced CR in 19 of 19 previously untreated patients (100%), eight of nine previously treated with RT (89%), and six of nine previously treated with RT and MOPP (67%). The remaining patients are all PRs tending toward CR status. The median time to CR was 3.0 months. The median time in remission to date for the previously untreated patients is 8+ months (2+-14+). After an induction period of eight cycles of chemotherapy patients are maintained on alternate-month treatment continuing the alternating sequence. During this phase three patients have experienced reappearance of disease (one recurrence, one possible second primary lymphoma, and one recurrence in a patient whose original diagnosis is in doubt). The regimen has been well tolerated. All patients were treated as outpatients. Alopecia and neurotoxicity were mild and myelosuppression was moderate. Clinically significant cardiopulmonary toxicity has been limited to mild radiation pneumonitis in one patient and bleomycin pneumonitis which cleared during prednisone in a second patient.

Adolescent↗
PubMed1975

Studies of cellular proliferation in human leukemia. VIII. The generation time and growth fraction in lymphosarcoma in a leukemic phase during advanced and early relapsing disease.

The kinetics of cell proliferation were studied in a patient with lymphosarcoma in a leukemic phase both before treatment when the disease was very advanced and again at the earliest sign of bone marrow relapse following a drug-induced remission. During advanced disease, the pulse 3H-TdR labeling index (LI) was 11%, the mitotic index (MI) was 0.4% the growth fraction (GF) was 0.6, and the generation time (TG), as measured by the median grain count halving time, was estimated to be 160 hours. The patient went into remission for 25 days after a short course of therapy with prednisolone and arabinosylcytosine (Ara-C). During early relapsing disease, the LI was 17%; MI, 1.1%; GF, 1.0; and TG, 85 hours. The results of this study suggest that the rate of cell proliferation slows in leukemia as the tumor mass increases in volume, and that the slower growth is due to an increase in cell generation time, a decrease in the growth fraction, and an increased rate of spontaneous cell loss.

Adult↗
PubMed1975

Proliferative kinetics of central nervous system (CNS) leukemia.

The proliferative kinetics of the leukemic cells in the cerebrospinal fluid (CSF) were studied in three adults with CNS leukemia after 18 and 8 months while receiving an intensive treatment regimen. One (J.L.) had acute myeloblastic leukemia and developed CNS disease after 5 years' treatment with arabinosylcytosine and 6-thioguanine. All were in marrow remission at the time of study. G.H. had had no therapy for CNS disease, A.K. had had intrathecal methotrexate 2 months previously, and J.L. had recently completed radiotherapy (1900 R) to the head. An Ommaya reservoir was placed in a lateral ventricle and 3H-thymidine was injected into the resrvoir every 12 hours for 10 days; samples of cells were obtained by lumbar puncture periodically for autoradiography. In all patients the flash 3H-thymidine labeling index (LI) of the leukemic cells was less than 2% (determined in vitro) and the mitotic index less than 0.1%. After 10 days of 3H-thymidine injections in vivo, the LIs of the leukemic cells were 55%, 36%, and 21% in G.H., A.K., and J.L., respectively. These findings indicate that leukemic cells may proliferate very slowly in the CNS, and stress the difficulty of eradicating CNS leukemia with chemotherapeutic agents which are only active against proliferating cells.

Acute Disease↗
PubMed1975

Treatment of acute leukemia in adults.

Improvement in the management of acute leukemia in adults has not progressed nearly so rapidly as has the treatment of childhood leukemia. One important difference is that most adults have myeloblastic or related forms of the disease (AML), whereas the majority of children have lymphoblastic leukemia (ALL). However, even adults with ALL fail to respond as well to a similar regimen as do children with the same type of leukemia. In a recent series of patients with ALL who were treated with the complex multiple drug "L-2" protocol, the incidence of complete remission in adults was 78% vs. 99% in children, and the median duration of remission was only 24 months in the adults, whereas it has not yet been reached in the children and is projected to be over 4 years. In AML and the related nonlymphoblastic forms of acute leukemia, therapy is still unsatisfactory in both adults and children. With the best current drug treatment schedules, the incidence of complete remission is now better than 50%, but it is often difficult to compare the exact remission rates in different series because of differences in reporting results. In adults treated with the multiple drug "L-6" protocol, the incidence of remission in previously untreated patients was 56% and the median duration of remission was 10 months. The median survival of all patients (responders and non-responders) was 1 year whereas that of responders only was 2 years. It is encouraging that a significant proportion of those patients with AML who have complete remissions now remain in remission for extended periods; about 45% of patients responding to the "L-6" protocol remained in remission over 1 year, and 18% have been in continuous remission for 2 to over 4 years. Even after discontinuing treatment, some patients with AML stay in remission for long periods, and it is possible that some of them may have been cured. If this proves to be true, it becomes of great importance to determine what is different about the patients who do exceptionally well as compared to the majority who continue to die within a year. However, no consistent nor distinctive favorable prognostic features have yet been identified.

Adolescent↗
PubMed1975

A scanning electron microscopic study of 34 cases of acute granulocytic, myelomonocytic, monoblastic and histiocytic leukemia.

This report describes the surface architecture of leukemic cells, as seen by scanning electron microscopy in 34 patients with acute nonlymphoblastic leukemia. Six patients with myeloblastic, 4 with promyelocytic, 10 with myelomonocytic, 8 with monocytic, 4 with histiocytic and 2 with undifferentiated leukemia were studied. Under the scanning electron microscope most leukemia histiocytes and monocytes appeared similar and were characterized by the presence of large, well developed broad-based ruffled membranes or prominent raised ridge-like profiles, resembling ithis respect normal monocytes. Most cells from patients with acute promyelocytic or myeloblastic leukemia exhibited narrower ridge-like profiles whereas some showed ruffles or microvilli. Patients with myelomonocytic leukemia showed mixed populations of cells with ridge-like profiles and ruffled membranes whereas cells from two patients with undifferentiated leukemia had smooth surfaces, similar to those encountered in cells from patients with acute lymphoblastic leukemia. It appears that nonlymphoblastic and lymphoblastic leukemia cells (particularly histiocytes and monocytes) can frequently be distinquished on the basis of their surface architecture. The surface features of leukemic histiocytes and monocytes are similar, suggesting that they may belong to the same cell series. The monocytes seem to have characteristic surface features recognizable with the scanning electron microscope and differ from most cells from patients with acute granulocytic leukemia. Although overlap of surface features and misidentification can occur, scanning electron microscopy is a useful adjunct to other modes of microscopy in the study and diagnosis of acute leukemia.

Acute Disease↗