Early membrane retrieval following exocytosis in rat mast cells

The fate of the surplus membrane following exocytosis of mast cell granules was studied by the extracellular tracer Ruthenium red (Ru red). Isolated rat peritoneal mast cells were stimulated with 4 micrograms/ml polylysine, washed and maintained in a culture medium for 80 min. Mast cells were observed both with the light microscope after adding Ru red in physiological solution and with the electron microscope after fixation in Ru red-containing fixatives. Whereas all exocytotic cavities were found to be stained with Ru red immediately after stimulation, a gradual lack of staining was observed in the subsequent period. The exits of the cavities were sealed by membrane fusions which resulted in closed vacuoles containing exocytosed granule remnants. These vacuoles often fused with each other to form a few giant vacuoles. The overwhelming majority of the vacuoles were observed to be closed 30 to 80 min after stimulation. In one experiment a quantitative analysis was performed to assess the degree of membrane recapture by sealing of the exocytotic cavities. A considerable portion of the plasma membrane area was retrieved in this way as early as between 15 and 30 min after stimulation. We conclude that the dominant mechanism of membrane retrieval in the early period following exocytosis is the recapture of large membrane areas by sealing of exocytotic cavities.

The effect of triiodothyronine-prednisolone treatment on the development of digestive enzymes in the suckling pig

Thirty suckling pigs of 4 litters were divided into an experimental and a control group. The experimental piglets were treated perorally from 14 to 20 days of age with rising doses of triiodothyronine, which were combined with prednisolone for the last 3 days. On the day following the conclusion of the treatment (at 3 weeks of age) the piglets were killed by bleeding for the determination of digestive enzymes. The experimental piglets showed a significant increase of intestinal trypsin (p less than 0.01) and pancreatic amylase (P less than 0.05) activities over the control; a significant decrease of gastric chymosin activity (P less than 0.05) was caused by the great inter-group differences within one litter. Ten of the 11 parameters tested indicated precocious maturation of the digestive enzymes of the experimental piglets, however, most of these differences were not significant. Further studies are required for the possible utilization of this finding in the early weaning practice.

[Premalignant and malignant changes in the epithelium in an antethoracic skin tube after esophagus replacement surgery]

Seven clinical cases are described of plastic repair of the stenosed oesophagus by means of a skin tube in which premalignant changes have developed after the lapse of several decades. The authors assume that these changes have been caused by chronic inflammation due to chemical irritation of the skin tube by stagnant food, saliva, and the gastro-"neo-oesophageal" reflux. On the basis of data from the literature and personal experience, the authors suggest that use of a skin tube in the repair of the oesophagus should be reserved for the small group of patients with oesophageal malignancy not amenable to other methods of reconstruction.

[Morphology and cytodynamics of oxazolone-induced cellular immune response]

Dynamics of lymphoid tissue changes induced by oxazolone, a contact allergen responsible for immune reaction of delayed type was studied. Basing on light-and electron microscopic findings and morphometrical analysis the following components of the reaction may be distinguished: an early active lymphocytic migration, a delayed paracortex proliferation and a following follicular response. In the regulation of the outflow of lymphocytes a primary role may be attributed to the endothelial lining of the postcapillary venules. For the morphological changes of endothelial cells an effect of circulating antigen specific lymphocytes may be responsible.

Rapid separation of rat peritoneal mast cells with Percoll

Rat peritoneal mast cells were separated by using density gradients of PVP-coated silica particles (Percoll). Mast cells were either isolated on preformed Percoll gradients or cell separation was made simultaneously with the gradient formation. Both procedures resulted in mast cell suspensions of 95 to 99 per cent purity. As tested by Ruthenium red staining and electron microscopy, the isolated mast cells showed a very good preservation of cell structure and reacted easily to the degranulating agent Compound 48/80. Practically all mast cells could be recovered from the peritoneal cell suspension. Percoll was found to be superior to earlier isolation procedures by giving a practically pure and intact mast cell suspension and by avoiding cell aggregation.

Polarization and fluorescent microscopy--simple methods for demonstrating pulmonary surfactant lipids

Birefringence and fluorochrome lipid staining with benzpyrene are demonstrated as simple morphological methods to reveal the presence or absence of surfactant lipids in human newborn lung tissue. Lack of lipid birefringence proves to be an associated finding in the lungs of premature infants with hyaline membrane disease, indicating the possible pathogenetical importance of surfactant deficiency.

Immune response in malnutrition. Effect of protein deficiency on the DNA synthetic response to alloantigens

To evaluate the DNA synthetic response to alloantigens by lymphocytes from mice fed diets with normal (27%) and low (8%) protein content, we quantitated the uptake of 125IUDR in spleens of lethally irradiated adult F1 hybrids injected with cells with parental C57BL/6 donors kept on either diet. Thymocytes, spleen and lymph node cells from protein-restricted parental mice synthesized higher amounts of DNA than those from normally fed controls. Added thymocytes from either malnourished or normal F1 hybrids had similar inhibitory effects on the response of an active parental inoculum. The results indicate that cells from mice kept on a moderately protein-deficient diet for 3--5 weeks after weaning, have increased capacity to proliferate in response to alloantigens, suggesting a high proportion of reactive cells and/or changes in the ratio of the interacting cell populations in their lymphoid organs.

Cell differentiation of the fetal rat anterior pituitary in vitro

Adenohypophysial primordia of rat embryos at 13 to 15 days gestation were cultured in Parker 199 synthetic medium for 2 to 11 days. At the end of the culture period their fine structure and the presence of immunoreactive trophic hormones using the peroxidase-labeled antibody technique were investigated. The degree of differentiation in the glands depends largely on the age of the embryos furnishing the explants. Cultured pituitaries explanted on the 13th day of gestation contain only ACTH-positive cells and about 15% of the cells are granular. The granules are 50-100 nm in diameter in some cells, while in other cells they range from 50 to 200 nm. In cultivated adenohypophysial primordia of embryos on the 15th day of intrauterine life ACTH, prolactin, LH and TSH cells are evident, but only the same two kinds of granular cells can be observed with the electron microscope. The extent of cytodifferentiation in the glands explanted on the 14th day of gestation is intermediate between the two other groups. The data suggest that the fetal rat pituitary has the capacity of self-differentiation but to a lesser extent than that of the in situ hypophysis.

[Simultaneous incidence of chronic dissecans aortic aneurysm and bidirectional tachydardia]

In a 68-year-old patient during a therapy with digitalis and saluretics with maintenance doses a severe cardiac insufficiency develops. After intravenous injection of K-strophantoside temporarily a bidirectional tachycardia developed which enforced a discontinuation of the K-strophantoside therapy. A deterioration of the cardiac insufficiency caused the resumption of the strophantine treatment under the protection of novocamide (procainamide) and panangine (magnesium asparagin. anhydr. and calcium asparagin. anhydr.) without reappearance of a bidirectional tachycardia. The patient died of a severe cardiovascular insufficiency. If the bidirectional tachycardia appears in severe cardiac insufficiency a continuation of the treatment with K-strophantoside can be tried under the protection of antiarrhythmic drugs.

[Topo-optical demonstration of lineal arrangement of vicial OH radicals by means of aldehyde bisulfite toluidine blue (ABT) reaction]

Topo-optical reaction with aldehyd-bisulfit-toluidinblue (ABT) suitable for the demonstration of lineal arrangement of vicinal OH-radicals is described. On the base of double refringement brought about by the orientated dye-binding, this reaction is suitable for the study of molecular arrangement of carbohydrate components of biological structures (glycoproteins, glycolipides and polysaccharides). Double refringement brought about by the reaction ABT optically is negative to the length of polysaccharide-chains. Practical use of the method is demonstrated on several biological structures. Findings show, that reaction ABT opens new possibilities for the study of ultrastructure of carbohydrate components of various tissue elements.

Tuberculosis of the breast

Tuberculosis of the breast is rare and very difficult to differentiate from breast cancer both clinically and radiologically. The authors summarize the clinical and radiographic characteristics of the disease on the basis of 6 cases.

Granulomatous orchitis and spermatic granuloma

One case of granulomatous orchitis and three cases of spermatic granuloma are described and the clinical and pathologic features of the two syndromes are discussed. Since no certain diagnosis is possible on clinical grounds alone, it rests on the evidence of pathology. Both granulomatous orchitis and spermatic granuloma are of practical importance to the specialists, the first being apt to mimic tumours, and the second to tuberculous epididymitis. Histological study, possibly of biopsy specimens, permits to differentiate either process from malignancy and from tuberculosis with certainty. It is to be emphasized that in many cases of chronic epididymitis with clinical suspicion of tuberculosis careful histological search reveals spermatic granuloma. Since the processes under discussion are unresponsive to antibiotics, their therapy is surgical.