Moshe Aronson

The leukergy test in patients with ischemic heart disease

In search of a simple method for potential evaluation of leukocyte aggregation in states of infarction, we compared the leukergy test, which consists of leukocyte aggregation visualized in a peripheral blood test, to the neutrophil aggregation activity (NAA) test, which consists of in vitro aggregation of neutrophils from normal donors by a patients plasma. Seventy-five patients participated in the study; 20 with ischemic heart disease and no infarction, 41 with relatively small myocardial infarctions, and 14 with large myocardial infarctions, the respective values of leukergy being 6.9 +/- 3.2, 10.8 +/- 4.6, and 20.5 +/- 14%. On the other hand, neutrophil aggregation activity was the same in a group of 10 patients without myocardial infarction and 10 with myocardial infarction. In these two groups, which showed no difference in the NAA test, the respective leukergy values were 4 +/- 1.5 and 21.7 +/- 10.6%. Thus leukergy correlates better with the clinical picture than does the NAA test.

Anti-neoplastic activity of paclitaxel on experimental superficial bladder cancer: In vivo and in vitro studies

The effects of intravesical administration of paclitaxel (taxol) in a bladder tumor model in mice, as well as the drugs in vitro activity on the same tumor cells, have been studied. Two cell lines, derived from MBT‐2 cells, were employed in these experiments. The T50 line (obtained by many passages in mice) was much more aggressive in vivo than the T5 line. In vivo paclitaxel treatment for 3 days after T5 implantation resulted in a considerable retardation of tumor growth, whereas under the same conditions the T50 line was much less, although still significantly, affected. When treatment was started 1 day after tumor implantation, both tumor variants were affected by paclitaxel to the same extent. The in vitro experiments utilized the MiCK assay, which allows continuous recording of the kinetics of cell growth. These studies revealed a 39.8% inhibition of cell growth by 2.10−8M paclitaxel in the T50 line and a 30‐fold increase in concentration had only a small additional effect on the degree of inhibition. At 2.10−8M paclitaxel, growth of T5 was inhibited by 21.7%, which increased to 35.2% at 6.10−7M. The treated cells displayed bundles of microtubuli, as described for other paclitaxel‐treated cells. Int. J. Cancer, 70:297–301, 1997.

Increased uptake and desulphaton of heparin by mouse macrophages in the presence of polycations

Heparin uptake and desulphation by cultured macrophages were investigated. Histones, polyamino-acids, protamine and eosinophil-basic protein stimulated both heparin uptake and desulphation, processes found to be non-related. Poly-L-ornithine and poly-DL-lysine increased the heparin uptake by about 33-fold, and histone produced up to 7.5-fold increase in the desulphation. The same polycations inhibited heparin desulphation by macrophage extracts.

Evaluation of disease activity in rheumatic patients by leucocyte adhesiveness/aggregation.

Previous work has shown that leucocyte adhesiveness/aggregation (LAA), as measured by the leukergy test, correlates well with disease severity in rheumatic patients. As LAA is probably a manifestation of the acute phase reaction various components of the acute phase reaction were measured in order to identify the best marker of disease activity. In addition to LAA, the following variables were measured in 79 patients with various rheumatic diseases and in 10 controls: white blood cell and platelet counts, erythrocyte sedimentation rate, haptoglobin, fibrinogen, C reactive protein, albumin, globulin, caeruloplasmin, alpha 1, alpha 2, beta, and gamma globulin, and haemoglobin concentrations. Patients were graded according to the state of their disease as mild, moderate, or severe. The extent of leucocyte adhesiveness/aggregation in peripheral blood proved to be the best laboratory variable for the grading of disease activity. Correct grading was obtained in 63% of the patients by means of the LAA, compared with 48% with C reactive protein, 41% with caeruloplasmin, 40% with haptoglobin, and 32% with haemoglobin. It is suggested that LAA of the peripheral blood during inflammation may be used as a reliable marker of disease severity.

Heparin receptors on mouse macrophages

This study deals with the nature of the attachment between the macrophage cell membrane and heparin molecules. Treatments intended to remove or internalise macrophage receptors (trypsinisation and stimulation of phagocytosis respectively) were shown to considerably modulate the attachment of heparin. An excess of heparin fractions ranging in mean molecular weight from 8100 to 25700 all inhibited attachment of 35S heparin as did a mixed isomer chondroitin sulphate preparation. Our study provides evidence for the presence of receptors for sulphated glycosamino-glycans on the mouse macrophage cell membrane.

Prevention of Ascending Pyelonephritis in Mice by Urease Inhibitors

The effect of 2 urease inhibitors, hydroxyurea and thiourea, on experimental ascending pyelonephritis by P. mirabilis was studied in mice undergoing water diuresis. It was found tha

The interaction of phagocytes and the large-sized parasite Cryptococcus neoformans: Cytochemical and ultrastructural study

SummaryThe yeast Cryptococcus neoformans may develop under certain conditions a large polysaccharide capsule 50–100 μM in diameter and therefore cannot be phagocytosed by either polymorphonuclear cells (PMNs) or mononuclear phagocytes (MNs). The cellular defense mechanism — in various animals — against the yeast is composed by formation of ringlike structure of PMNs or MNs cells which surround the C. neoformans. Ring structures develop either in vivo or in vitro in tissue culture; destruction of the yeast occurs within 36–72 hours.Several hydrolases, such as acid phosphatase, β-glucuronidase and non-specific esterase were found to be released from the phagocytic cells into the enclosed yeast. Considerable reduction of NBT used as a marker for oxidative activity was observed in MN rings at contact regions of the MN cells and the yeast. Electron microscopic studies indicate that the phagocytic cells in the ring structure have many pseudopodes penetrating into the polysaccharide capsule of the yeast. Disintegration of the capsule was observed as well as phagocytosis of its material. A possible analogy between normal phagocytosis of small-sized bodies and the ring structure obtained when large bodies are involved is discussed.

Polycations as possible substitutes for protamine in heparin neutralization

Abstract Protamine has long been used for the neutralization of heparin excess in clinical situations, but it does have several drawbacks such as being anticoagulatory itself, when in excess, or at times causing heparin rebound, when at verge of neutralization. In an attempt to find better substitutes for protamine, synthetic polyamino-acids and various types of histone were considered and their activity as heparin antagonists was compared to that of protamine. While protamine was found superior to histones in neutralizing heparin under all the test conditions, poly-DL-lysine showed a wider range of neutralization than did protamine. This particular substance, however, is unsuitable because of its toxicity, and it is recommended to search for additional synthetic polymers. Some of the properties to be desired in a heparin neutralizer are enumerated.

The state of leukocyte adhesiveness/aggregation in the peripheral blood is more sensitive than the white blood cell count for the detection of acute mental stress

We determined the state of the leukocyte adhesiveness/aggregation in the peripheral blood by using a simple slide test and found it to be more sensitive than the white blood cell count for the detection of acute mental stress. Included were 71 controls, 64 young athletes examined just before their exercise, 14 volunteers who were examined 10-20 min before engagement in rappelling while an additional group of 20 were examined just before the act as they were facing an abyss from the top of a cliff. The state of leukocyte adhesiveness/aggregation correlated significantly (p less than 0.0005) only with the increasing strain assumed to occur from the first to the fourth group. The state of leukocyte adhesiveness/aggregation was 3.3 x more sensitive than white blood cell count in both rappelling groups and 5 x more sensitive than white blood cell count when evaluated in those examined at the last minute. We concluded that the state of leukocyte adhesiveness/aggregation is a reliable marker of acute mental stress.

The state of leucocyte adhesiveness/aggregation (LAA) in the peripheral blood of burned mice: an early and sensitive inflammatory indicator and a marker of pulmonary leukostasis

The inflammatory response during thermal injury increases the adhesiveness of white blood cells. A direct slide test was used to compare the state of leucocyte adhesiveness/aggregation (LAA) in the peripheral blood of mice subjected to a thermal injury with the findings in control animals. The state of LAA in the peripheral blood increased from baseline values of 1.1 +/- 1.1 per cent to 6.5 +/- 1.3 per cent within 1 h and to 11.0 +/- 1.2 per cent and 14.8 +/- 4 per cent after 3 and 6 h respectively following thermal injury. The respective leucocyte counts were 3075 +/- 277/mm3 (baseline), 3871 +/- 359, 3840 +/- 687 and 6395 +/- 1152 cells/mm3. The LAA values had subsided by 5 days following burning and correlated with the degree of pulmonary leukostasis. Our study suggests that the LAA is an early and sensitive marker of inflammation and that it can be used as a marker for the presence of pulmonary leukostasis during thermal injury.