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Biomedical subjects

M P Westerman

Publications and source records attributed to M P Westerman.

At least 55 records · Page 3Linked to original sources
PubMed1983

Subpopulation of human helper and suppressor T lymphocytes.

Mitogen driven differentiation of normal human mononuclear cells is a well-established model for the study of antibody synthesis in man. In certain rare individuals who are clinically normal, unfractionated mononuclear cells or a mixture of purified B plus T lymphocytes differentiate into immunoglobulin producing cells in response to purified protein derivative of tuberculin (PPD) but not in response to pokeweed mitogen (PWM). To evaluate this observation we have irradiated T cells from such individuals to eliminate naturally occurring suppressor T cell activity and then added the irradiated T cells back to autologous B cells before culture. The B cells then responded to PWM. The original PPD responses of cells from these individuals were now significantly reduced. Although, there was no difference between PWM nonresponders and responders in the number of OKT-8 positive cells, elimination of OKT-8 positive cells in the PWM nonresponders with OKT-8 monoclonal antibody and complement resulted in a significantly increased response to PWM. This study indicates that there are suppressor T cells which specifically inhibit B cell response to PWM without affecting the PPD response. These results also show that the helper T cells involved in the PWM response are radioresistant and those involved in the PPD response are radiosensitive.

Antibodies, Monoclonal↗
PubMed1983

Red blood cell morphology in sickle cell anemia as determined by image processing analysis: the relationship to painful crises.

Red blood cell morphology was studied in the peripheral blood of adults with sickle cell anemia to determine if changes occur during painful crises. Image processing of the cells with an automated system of red blood cell analysis was used. Four groups of cells were observed: normocytes, macrocytes, target cells, and cells with the shape of irreversibly sickled cells. During asymptomatic periods, the percentages of these cells differed in each individual but were typical for that individual and generally were stable. During crises, macrocytosis occurred and the concentration of irreversibly sickled cells showed greater fluctuation. The macrocytosis most likely reflected a marrow response to increased hemolysis and demonstrated that the increased red blood cell destruction observed during pain crises may be more extensive than previously considered. Changes in the concentration of irreversibly sickled cells during crises were not consistent and could not be used as an indicator of a crisis. Image processing with automated red blood cell analysis allows for accurate assessment of all the morphologic groups of red blood cells in patients with sickle cell anemia and compares well with standard methods for measuring the concentration of irreversibly sickled cells.

Adult↗
PubMed1983

Effects of valinomycin, A23187 and repetitive sickling on irreversible sickle cell formation.

The formation of irreversibly sickled red cells has been studied by inducing cell shrinkage, ion loss, Ca2+ accumulation and membrane loss either singly or in combination. Valinomycin, A23187+Ca2+ or hypertonic saline caused shrinkage of the cells with retention of the sickled form after reoxygenation. The cells which had retained the sickle shape after treatment with the ionophores and reoxygenation remained sickled after exposure to hypotonic media. These cells were also osmotically insensitive. Retention of the sickled form was not dependent upon membrane loss as induced by repeated sickle-unsickle cycles or by A23187+Ca2+ treatment although repetitive sickling did give rise to shorter, stubbier spicules. Sickled red cells, either the endogenous irreversibly sickled cells or the sickled cells induced by deoxygenation, did not lose membrane by vesicle or spicule loss as normal cells or oxygenated sickle red cells do. Cell water loss without cell membrane loss appears to be an important factor in the irreversible sickling of red cells.

Anemia, Sickle Cell↗
PubMed1981

Microvesicles from sickle erythrocytes and their relation to irreversible sickling.

Incubation of sickle (HbS) erythrocytes for periods up to 96 h leads to the formation of irreversibly sickled cells (ISCs) and to the release of spectrin-free microvesicles similar to those derived from aged or Ca2+-ionophore-treated normal erythrocytes. The sickle microvesicles were somewhat larger than those from normal cells and showed minor differences in their membrane polypeptide composition. Sickle microvesicles were no different from their parent cells in their content of fetal haemoglobin. Neither microvesiculation nor formation of irreversibly sickled cells required the presence of Ca2+ in the medium but Ca2+ did accelerate both processes. Although in these prolonged incubations microvesiculation appeared to occur concomitantly with the formation of ISCs, it is not clear whether or not microvesiculation is a necessary prelude to irreversible sickling.

Anemia, Sickle Cell↗
PubMed1980

Asplenia and abnormal neutrophil kinetics in chronic idiopathic neutrophilia.

Chronic idiopathic neutrophilia is a rarely recognized finding in otherwise healthy subjects. Described here is a case, not previously reported; in which the patient also had congenital asplenia. Studies carried out to determine the mechanism for the neutrophilia are also described. The results show that the patient's neutrophilia was associated with an enlarged circulating pool of neutrophils, increased production and utilization of neutrophils and a short blood granulocyte survival. The findings differ completely from those observed in patients with chronic idiopathic neutrophilia and intact spleens. The results suggest that (1) the mechanism for neutrophilia in patients with chronic idiopathic neutrophilia varies and depends upon the presence or absence of the spleen, and (2) the spleen has a role in the control of neutrophil production, distribution and utilization.

Bone Marrow Cells↗
PubMed1980

Assessment of the anemia of chronic disease by digital image processing of erythrocytes.

Eighteen patients with the anemia of chronic disease were studied to determine the usefulness and accuracy of image processing analysis of erythrocytes for diagnosis. Diagnostic tests used for comparison included estimates of serum ferritin, serum iron and iron-binding capacity, stainable marrow iron, and erythrocyte morphology as determined by standard methods. The findings show that the analyses obtained by image processing were diagnostic for 83% of the patients with chronic disease. Serum ferritin levels were supportive of diagnosis for 33% of the patients, and serum iron levels were useful for approximately 25% of the patients. Cell indices and marrow iron were of limited value. The study demonstrates that quantitative information obtained by digital image processing of erythrocytes can be very useful for the diagnosis of the anemia of chronic disease.

Anemia↗
PubMed1979

Membrane components in the red cells of patients with sickle cell anemia. Relationship to cell aging and to irreversibility of sickling.

Cholesterol, phospholipid and sialic acid were measured in red cells from patients with sickle cell anemia to determine whether the cells had abnormal concentrations of these components and whether the amounts of these compounds differed in irreversibly sickled cells as compared to non-irreversibly sickled cells. Sickle cells had significantly higher levels of both lipids than similar populations of normal cells, however, comparisons to populations of young control cells showed that the differences were generally not significant. Sialic acid levels in sickle cells were not significantly different from normal cells. Irreversibly sickled cells had lower lipid and sialic acid concentrations than those not irreversibly sickled, but the differences were either not significant or did not occur when compared to young control cells. The studies show that the increased lipid concentrations in the membrane of sickle cells are not abnormal but are related to cell age and that the decrease in membrane components in irreversibly sickled cells is no greater than would be predicted for similarly aged populations of cells.

Anemia, Sickle Cell↗
PubMed1979

An evaluation of cellularity in various types of bone marrow specimens.

Comparisons of marrow cellularity determinations in needle biopsy sections, aspirated smears of marrow particles, and aspirated clot sections were made using the point-counting and standard visual methods of measurement. Good correlations of cellularity between biopsies and smears were obtained with the point-counting method. This occurred with either single- or multiple-observer measurements, and differed from the wide observer-to-observer variation obtained in the other comparisons. Although the optimal method for cellularity measurements is point counting by biopsy sections, the findings indicate that aspirated smears of marrow particles can be a suitable substitute for needle biopsy sections when point counting is used. This would be particularly useful in clinical settings necessitating frequent cellularity assessments. The results also show that the standard visual method of cellularity measurement is satisfactory when specimens are evaluated by one observer. The point-counting method of measurement, although the most accurate, is not as reproducible among observers as previously considered.

Biopsy, Needle↗
PubMed1978

Bullets, lead poisoning and thyrotoxicosis.

A patient with a retained bullet developed lead poisoning in association with thyrotoxicosis. The clinical and laboratory data suggest that lead was mobilized from an increased mobile bone pool during the hypermetabolic period with resultant poisoning. The findings give factual support to earlier concepts that lead poisoning may occur during periods of metabolic change in an individual with an increased body lead burden.

Adult↗
PubMed1977

Stainable iron in aspirated and needle-biopsy specimens of marrow: a source of error.

Marrow iron was assessed in needle biopsy sections and in simultaneously obtained aspirated smears and aspirated clot sections from 251 patients. Significantly different amounts of stainable iron were observed in needle biopsy sections and aspirated smears in 15% of the specimens. The usual difference consisted of significantly less stainable iron in needle biopsy sections as compared to the aspirated smears (13%). Of clinical importance was the finding of absent stainable iron in 8% of the needle biopsy sections, in contrast to the definite deposits observed in the corresponding aspirated smear. Of similar interest was the observation that 6% of the needle biopsy sections had significantly less stainable iron than corresponding hemosiderotic smears. The amounts of stainable iron in needle biopsy sections were similar to the amounts observed in the corresponding aspirated clot sections. Evaluation of marrow iron using needle biopsy sections as well as aspirated clot sections differs from results observed in aspirated smears and could be a source of significant error in the assessment of iron stores.

Biopsy, Needle↗
PubMed1976

Chronic anemia, wound healing, and red cell 2,3-diphosphoglycerate.

Relationships between various types of chronic anemia, wound healing, and red cell 2,3-diphosphoglycerate (2,3 DPG) were examined in rabbits. Wound tensile strength and energy absorption were not affected by chronic iron-deficiency anemia, the chronic hemolytic anemia caused by intravenous water infusion nor by chronic hemolytic anemia caused by intravenous water infusion nor by chronic phenylhydrazine-induced anemia. Red cell 2,3 DPG levels were increased in the anemia of iron deficiency and were normal in the rabbits with chronic phenylhydrazine-induced anemia at the time of wound excision but were low following phynylhydrazine injection. The results show that chronic anemia per se does not affect the tensile strength and energy adsorption of wound healing. The findings suggest that the wound healing process may differ in certain types of anemia.

Anemia↗
PubMed1975

Hypocholesterolaemia and anaemia.

The present study has examined the relationship and significance of hypocholesterolaemia to anaemia and to the red cell. The level of plasma cholesterol is closely related to haematocrit levels both initially and throughout the course of the anaemias associated with hypocholesterolaemia. The association is maintained, regardless of the cause of the haematocrit change, i.e. transfusion or response to treatment. Hypocholesterolaemia does not affect the red cell, i.e. its survival, cholesterol concentration or osmotic fragility and occurs in a diverse group of anaemias. As such, it is not causally related to anaemia. The changes in plasma cholesterol are most likely related to its 'redistribution' or to plasma 'dilution', with contributory factors occurring. The presence of anaemia, even to a modest degree, would be important to consider when comparing cholesterol levels between groups of individuals.

Anemia↗
PubMed1975

Radiophosphate (32-PO4) incorporation into phosphatidic acid of lead-poisoned and normalred cells.

Radiophosphate incorporation into phosphatidic acid is decreased in the red cells of lead-poisoned humans and rabbits. The decrease in activity is not related to the length of red cell survival nor to the differences in osmotic fragility observed in the lead-poisoned cells. Incorporation of radiophosphate into phosphatidic acid of normal red cells is sulfhydryl dependent and occurs at the cell surface. Lipid composition of the red cell membrane of the lead-poisoned humans and rabbits is normal.

Acetates↗