Rosette formation of tumor cells with concanavalin A treated erythrocytes

Summary Trypsinized human erythrocytes were incubated with concanavalin A at 4°C. After removal of free concanavalin A, the erythrocytes were incubated with Ehrlich ascites tumor cells at 37°C. The erythrocytes formed rosettes with the tumor cells.     

Cocci and diphtheroids in blood cultures from patients in various pathological situations

The evolution of cocci and diphtheroids taking origin from cell-wall-deficient forms seems not to be related to a particular state of illness, but to be the consequence of a generalized crypto-infection.     

Cocci and diphtheroids in blood cultures from patients in various pathological situations

Summary The evolution of cocci and diphtheroids taking origin from cell-wall-deficient forms seems not to be related to a particular state of illness, but to be the consequence of a generalized crypto-infection.     

SEM observation of cultured,mitogen-stimulated leukocytes. Cells obtained from patients with acute myeloblastic and chronic lymphocytic leukemias

Summary SEM observation of acute myeloblastic leukemia cells, incubated for 20 h with the mitogens pokeweed and phytohaemagglutinin, showed these to have elongated structures that were either smooth or partially covered by thumblike figures. By contrast, the chronic lymphocytic leukemia cells possessed more compact shapes and some were covered with blebs of varying sizes.Supported by grant No. A3624 from the Natural Sciences and Engineering Research Council of Canada.We would like to acknowledge the help of Mr Jean-Luc Verville and Mrs Diane Keating from this Department. Our thanks also go to Dr J.F. Perdue, Lady Davis Institute for Medical Research of the Jewish General Hospital, Montreal, Canada, for the very generous use of his equipment and also to Mr Pierre Daigneault from M. E. C. A. Laboratories.     

Regulation of lymphokine production in peripheral blood mononuclear cell cultures

Summary An increase in the production of macrophage migration inhibitory factor, chemotactic factor for neutrophils, and skin reactive factor, was observed in lymphocyte cultures if the cells were allowed to age in culture for 24 h. The increased lymphokine production was reduced by adding concanavalin A-stimulated and mitomycin C-treated suppressor cells. It is suggested that the lymphokine production could be regulated by suppressive mononuclear cells.This work was supported by the Scientific Research Council, Ministry of Health, Hungary (Code No. 421 0304011/S).     

Regulation of lymphokine production in peripheral blood mononuclear cell cultures

An increase in the production of macrophage migration inhibitory factor, chemotactic factor for neutrophils, and skin reactive factor, was observed in lymphocyte cultures if the cells were allowed to age in culture for 24 h. The increased lymphokine production was reduced by adding concanavalin A-stimulated and mitomycin C-treated suppressor cells. It is suggested that the lymphokine production could be regulated by suppressive mononuclear cells.     

Amino acid concentrations in blood of patients with an acute myocardial infarction

Summary Levels of essential and nonessential amino acids in blood of patients with an acute myocardial infarction (AMI) were found in general not to differ from values obtained from non-AMI patients. This is in contrast to blood taurine levels which are elevated in the AMI patients.     

Ropalocytosis in acute leukemia

Summary Unusual club-shaped processes have been seen in the lymphoblasts in the peripheral blood of case of untreated acute leukemia. These arose from a single area of the cell surface and appeared identical to the morphologic change seen in ropalocytosis in red cells. Red cells in the peripheral blood were also affected.     

Glycogenosis type II: Glycogen storage in cell cultures from muscle

Riassunto è stata eseguita la coltura in vitro di frammenti di muscolo e di cute di un soggetto affetto da glicogenosi di tipo II.é stato osservato un accumulo di materiale PAS positivo, digeribile con la diastasi, nelle cellule derivate dal muscolo ma non in quelle derivate dalla cute.     

Rosette formation by human T and B lymphocytes in the presence of adrenergic and cholinergic drugs

Summary It was shown that adrenergic drugs, which increase the intracellular levels of cAMP, inhibit the rosette formation by T-lymphocytes, but stimulate the rosettes produced by B-lymphocytes. Cholinergic drugs, which increase the levels of cGMP, on the contrary, stimulate the formation of rosettes by T-lymphocytes but inhibit those produced by B-lymphocytes.Acknowledgments. This investigation was supported by Grant from National Council for Scientific and Technological Development (CNPq), Rio de Janeiro, Brazil.     

Inducement of blood vessel formation by ovarian extracts from mice injected with gonadotropins

Summary Ovarian extracts prepared from immature mice injected with human chorionic gonadotropin (hCG) and pregnant mare serum gonadotropin (PMSG) were assayed for angiogenic activity. The assay method consisted of implanting a film coated with ovarian extracts to the lateral wall of the m.rectus abdominus of a mouse for 20 days and examining the site for vascularization. The higher angiogenic activity obtained with PMSG-treated extract may be related to its follicle stimulating activity.Acknowledgment. Part of this work was supported by a grant from The Ministry of Education, Japan (No. 576165).     

Effect of high doses of somatostatin on adenylate cyclase activity in peripheral mononuclear leukocytes from normal subjects and from acute leukemia patients

Summary In normal lymphocytes somatostatin non-competitively inhibited basal (ID₅₀ 5×10^–4 M) and isoproterenol- and forskolin-stimulated adenylate cyclase activity (Ac). In acute leukemia blasts, non-responsive to isoproterenol, forskolin, which activates the catalytic subunit, stimulated and somatostatin inhibited Ac, thus indicating the leukemic enzyme, though defective, retains the inhibitory pathway and catalyst function.