Cell surface coatings and membrane potentials of malignant and nonmalignant cells.

A positive surface potential indicating a cell coating is common to malignant cells, lymphocytes, and normal and malignant trophoblastic cells. This characteristic was not generally found for other normal cell types tested by microelectrode penetration.

Correlation of perinatal brain growth with age, body size, sex, and race.

This study compares the weight of the human brain to gestational age and body dimensions. A new formula for calculating the rate of growth is proposed. It consists of a second order polynomial function: Y = A0 + A1X + A2X2, in which Y is brain weight, body weight, height, or body surface area; X is gestational age in weeks and A0, A1, and A2 are statistically estimated coefficients. In utero, the growth rate is most rapid for body weight, followed in decreasing order by brain weight, body surface area, and height. Brain growth is the same for both sexes in black and white races; it accelerates between the 20th and 45th weeks of gestation. The size of the newborn infant brain is directly related to gestational age and body size and is not determined by sex or race.

The effect of bovine lung heparin on normal human platelets as measured by electronic particle size analysis.

The response of normal human platelets to treatment with bovine lung heparin was evaluated using electronic particle size analysis and aggregometry. Samples for electronic particle size analysis were obtained both before and after the addition of heparin to platelet-rich plasma (PRP). The number of single platelets decreased significantly after the addition of heparin to PRP obtained from 22 individuals. This decrease averaged 18% in 19 samples which did not show a significant increase in transmittance and was at least 70% in 3 samples which showed a significant increase in transmittance. The size distribution of single platelets was not significantly altered. In addition, electron microscopic examination revealed that platelets treated with heparin are activated.

Collagen-induced platelet aggregation as studies by electronic particle size analysis.

The collagen-induced response of free platelets during aggregation was measured with an electronic particle size analyzer. Aggregation was induced in platelet-rich plasma by 0.05 mg/mL collagen. The reaction was followed turbidimetrically and samples for electronic particle size analysis were obtained during aggregation. Free platelet number decreased rapidly after the addition of collagen. This decrease preceded detectable changes in transmittance and a significant reduction in free platelet number was measured during the classical lag phase. In addition, the size distribution of free platelets at various times after the addition of collagen was not significantly altered indicating that large platelets are not preferentially involved in collagen-induced aggregation.

The measurement of lymphocyte size and thymidine uptake in comparative response to mitogen stimulation in vitro.

Measurements of thymidine uptake and cell size with the Coulter ZBI Counter and C-1000 channelyzer were found to be comparable for mitogen-stimulated lymphocytes. These two technics show a discrete relation with correlated regions of high and low response. Electronic sizing was correlated linearly to microscopic sizing of lymphoblasts. The reproducibility of radiolabeled and electronic sizing measurements were similar and significantly better than that of manual microscopic sizing. The distribution of lymphocyte sizes after two or three days in culture with mitogen was found to be bimodal. This facilitated the direct detection of stimulation responses with the ZBI counter.

Platelet aggregation induced by antilymphocyte serum. 2. Two modes of the aggregation mechanism.

The ability to inhibit the release reaction was found to correlate well with the ability to inhibit aggregation in washed human platelets exposed to antilymphocyte serum (ALS). However, the primary mechanism that contributes to ALS-induced aggregation in unwashed platelets appeared to be different from that found in washed platelets. Prostaglandin E1 and other release inhibitors were less effective in inhibiting aggregation in unwashed than in washed platelets. Salyrgan (mersalyl) in the presence of ALS or bovine fibrinogen produced an aggregation response in unwashed platelets that resembled the primary phase of aggregation. Two modes of the aggregation mechanism were evolved and are discussed.

Image analysis confirmation of DNA aneuploidy in flow cytometric DNA distributions having a wide coefficient of variation of the G0/G1 peak.

With nuclei extracted from paraffin-embedded tissues, resolution of normal diploid DNA and abnormal near-diploid/aneuploid populations by flow cytometry (FCM) is especially difficult. These samples, compared with fresh tissue, tend to show a broader DNA distribution, appearing as a wide (high) coefficient of variation (CV) of the G0/G1 peak. To address the question of whether there may be aneuploid populations hidden in wide CV diploid G0/G1 peaks, the authors measured DNA content in nuclei extracted from paraffin-embedded tumor tissue by morphometric image analysis (IA) in addition to FCM. Of 29 samples showing little evidence of DNA aneuploidy by FCM, in 20 of 20 with G0/G1 CVs greater than or equal to 5.50% there was an aneuploid population when analysis was performed by IA. Of the remaining nine samples with CVs less than or equal to 4.41%, all were diploid in the G0/G1 region by both FCM and IA. The presence of aneuploid populations in FCM distributions with wide CV G0/G1 peaks can be confirmed by IA.

Platelet aggregation and the ouabain-insensitive ATPase. Ecto-ATPase, reflection of membrane integrity.

The ecto-ATPase activity of washed human platelets has been characterized by a higher-performance liquid chromatographic method. Mg++ was found to stimulate ecto-ATPase activity more strongly than Ca++. The combination of Mg++ and Ca++ at increasing concentrations caused diminishing activity levels. Elevated ecto-ATPase activity was also found in platelets incubated with prostaglandin E1 (PGE1) or potassium cyanide (KCN). It is proposed that the increase of ecto-ATPase activity is related to the extrusion or exposure of plasma membrane containing a ouabain-insensitive ATPase. The role of ecto-ATPase in platelet aggregation is discussed in light of these findings.

Carcinoembryonic antigen and L-fucose in malignant and benign mammary disease.

A prospective study of 123 patients was undertaken to determine whether carcinoembryonic antigen (CEA) or L-fucose could be used as "tumor markers" to distinguish patients who had mammary cancer (41) from patients who had benign mammary disease (41) and patients who did not have mammary cancer (41). The predictive value of positive test results for both L-fucose and CEA was lower for patients who smoked than for those who did not. The sensitivities of CEA and L-fucose indicators are both below 55%. There were frequent false-positive and false-negative results. A substantial overlap in the levels of CEA and L-fucose was found for the patients who had mammary cancer and those who had benign mammary disease. CEA and L-fucose performed similarly in distinguishing cancer from benign disease. For patients who smoked, however, the predictive value of L-fucose was only 44%. The effect of smoking on L-fucose levels may account for discrepancies in L-fucose data reported in previous studies of mammary cancer. Neither CEA nor L-fucose were found to be of value in screening for mammary cancer.

Air bubbles and temperature effect on blood gas analysis.

The effect of temperature, time of storage, and presence of air bubbles in specimens for blood gas analysis was studied. The results show that air bubbles in a 10% proportion are undesirable because of significant elevation in the PO2, and the storage of anaerobic blood samples at room temperature (25 degrees C) is acceptable when measurements are done within the first 20 minutes.

A compartmental model of platelet aggregation in vitro: the kinetics of single platelets.

A compartmental model of platelet aggregation which accurately describes both reversible and irreversible aggregation in vitro is presented. This model is substantiated by correlative analyses of agonist-induced aggregation as monitored by both routine aggregometry and resistive counting of single platelets. Previously unresolved differences in the reported reaction order of the aggregation process are explained. The model suggests that aggregation includes, in addition to the association and dissociation of platelets, the stabilization of aggregates. We find reversible aggregation requires that single platelets associate more rapidly than aggregates stabilize. For irreversible aggregation, our results suggest the presence of subpopulations of single platelets which associate at different rates. As an unexpected consequence of this study, quantitative relationships between photometric and resistive methods of monitoring platelet aggregation are elucidated.

A platelet aggregating factor in thrombotic thrombocytopenic purpura: initial activity, fluctuations, and removal by plasma exchange.

A factor capable of aggregating normal platelets was found in the plasma of six consecutive patients with thrombotic thrombocytopenic purpura (TTP). The activity of the aggregating factor in whole plasma, the cold protein fraction from plasma and the residual supernatant was monitored during each patient's course of therapeutic plasma exchange. Although two patients demonstrated the highest level of aggregating activity at the time of diagnosis, the level fluctuated in five of six patients. Increasing levels of activity were usually accompanied by signs of clinical deterioration. Activity repeatedly within the normal range was not seen until remission of the syndrome. Neutralization of the aggregating activity in vivo through removal of patient plasma and replacement with fresh frozen plasma (plasma exchange) was accomplished less readily and less predictably than by mixing patient plasma and normal plasma in vitro. Use of the aggregating factor level in evaluating the need of plasma exchange is discussed.

Rapid determination of the rate constant of agonist-induced association of single platelets.

We have developed a rapid and convenient method for determining the rate constant of association of single platelets. Using the concentration of single platelets prior to activation and that 0.25 min (15 s) after activation, this rate constant can be determined accurately without concern for reversibility of the aggregation process or need for statistical analysis. A linear relationship between initial platelet concentration and the rate constant of association is defined. The clinical utility of this association parameter is discussed.

Interpretation of microscopic image analysis of cell nuclei.

This study shows that microscopic image analyses of nuclear DNA have common characteristics among fixation methods and tissue types. We find that microscopic imaging measurements require both nuclear area and DNA concentration to properly convey diagnostic information. Algorithms are developed which enable infiltrating lymphocytes to act as internal DNA controls for each sample. The DNA content and patterns measured by microscopic imaging were found to be related to patient survival and to cytologic diagnosis.

Cardiopulmonary responses of asthmatic children to strenuous exercise. Effect of theophylline.

The purpose of the study were to investigate the cardiopulmonary adaptations of asthmatic children to physical exercise and to evaluate the effects of theophylline. Two groups of children were evaluated. Eight asthmatic children participated in two exercise sessions. Half of the patients received theophylline in predetermined doses during the first session and half prior to the second session. Seventeen normal children matched for age, height, and weight served as controls. Various cardiorespiratory parameters were measured every 2 minutes during exercise and prior to termination of maximal physical effort. The results indicate that children with chronic asthma reach the range of predicted maximal aerobic capacity for their age. Theophylline increases the endurance of asthmatic children to maximal physical efforts without improving the cardiorespiratory parameters that were measured. The use of theophylline in therapeutic doses appears safe under conditions of vigorous exercise.

Selection of morphometric features that identify responders and nonresponders in stage IV Wilms' tumors.

Wilms' tumor is the most common renal malignancy of childhood. The use of histologic grade and stage has divided those patients into two main groups, responders and nonresponders, based on the absence or presence of extreme cytologic atypia (anaplasia). Patients with Wilms' tumor who have favorable histology experience excellent cure rates with relatively conservative treatment regimens. However, some patients with a favorable histologic diagnosis die of the disease. Destained hematoxylin and eosin-stained tissue sections were restained stoichiometrically with Feulgen stain, and 100 tumor cells per case were measured on a CAS 200 running CMP software. Using multivariant stepwise discriminant analysis on 13 cases of stage IV, favorable-histology Wilms' tumor, we successfully classified 92% of individuals into their correct prognostic groupings using 10 features of the quantitative morphology of tumor cells, including six Markovian textures. This morphometric technique may identify patients who can benefit from reduced therapy and those who must be treated with the more aggressive, classic therapy regimens.