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PubMed1977

[Analysis of different reactive changes in nerve fibers].

A study was made of the morphological peculiarities of the varicose corpuscles revealed in man and animals at the terminal stages of ontogenesis along the peripheral nerve fibers. The properties of these varicose bodies were compared with the reactive varicose deformities experimentally observed under conditions of disturbed blood supply. Similar features of the two formations compared and the presence of transitional forms permit to regard the former ones as the reactive structures. However, more time and participation of the surrounding tissue is required for their formation.

Aged↗
PubMed1977

[Diagnosis of candidid colpitis by Microstix -Candida (author's transl)].

The increase in the clinical significance of candida albicans in gynecology, particularly the high incidence (candidiasis) in the pregnant woman, demand an easy, efficient and rapid method for the routine diagnosis of candida albicans. Microstix -Candida, a specially developed dry culture medium in miniature form, has been studied in comparison to the conventional Nickerson's Medium. Good agreement of the data was obtained in 425 patients. The main advantages are the ease of handling and the 24 hour incubation period. The observed difference in data obtained from the phase microscope examinations and the Microstix Candida cultured specimens are discussed in detail.

Adolescent↗
PubMed1977

A new method for the isolation of renal basement membranes.

A method is described for the isolation of basement membranes from rabbit renal cortex in which the detergent N-lauroyl sarcosine is used as the disruptive agent. The isolated membranes have been compared with membranes prepared using ultrasonication and they were comparable both in terms of purity and gross chemical composition. Glomerular and tubular basement membranes were isolated by first separating glomeruli from tubules by density gradient centrifugation followed by detergent treatment of the separated tissues. The detergent method has the advantage that the basement membranes retained their native structure to a large degree, whereas sonicated membranes were severely fragmented. Collagen fibres were a significant contaminant in both preparations and were revealed more clearly by negative staining than by examination of thin sections. Studies with the detergent-treated membrane revealed that a few proteins, which seemed to be membrane components, were extracted with 1 M NaCl and that these proteins were lost from the basement membranes during sonication used in the conventional isolation procedure.

Amino Acids↗
PubMedDate not supplied

[Kinematics of fibroblast spreading. II. Individual locomotor activity].

An analysis of area changes of normal mouse fibroblasts during their spreading is made with time intervals of 5-50 s. A mean increase of the area takes place simultaneously with area fluctuations of various rhythms, which result from accidental undulations of the lamella edge. The fluctuations are also the same during intermediate temporary stopping of cell spreading. The central cell region--endoplasm--is stretched passively by centrifugal lamella forces and is an active antagonist of forces in squeeze processes. A description is made of the lamella edge undulations like the phase states change of protraction and retraction, and it is shown by two-dimensional phase diagrams that edge-activity has a zone organisation. These zones can migrate upon the cell perimeter as a wave in stohastic excitable medium.

Animals↗
PubMed1977

Role of vitamin E in glutathione-induced oxidant stress: methemoglobin, lipid peroxidation, and hemolysis.

Red blood cells (RBC) from normal and vitamin E-deficient rats were incubated in a hypertonic solution of reduced glutathione adjusted to pH 8. Methemoglobin formation occurred in intact RBC from both normal and vitamin E-deficient rats. Hemolysis was significantly greater in RBC from vitamin E-deficient rats. Experiments with catalase, superoxide dismutase, and methional showed that H(2)O(2) was the primary extracellular source of oxidant stress. Extracellular superoxide and hydroxyl radical were not involved in oxidant stress. Experiments with dimethyl sulfoxide showed that intracellular hydroxyl radical, generated from H(2)O(2), was the hemolytic agent. Neither methemoglobin formation nor lipid peroxidation involved hydroxyl radical. Indeed, lipid peroxidation and hemolysis in RBC from vitamin E-deficient rats were concurrent rather than consecutive events. Phase contrast microscopy showed that rigid, crenated RBC with a precipitate around the interior periphery formed during glutathione-induced oxidant stress. The precipitate dissolved slowly as the crenated RBC were converted to smooth ghosts. It appeared that protein precipitates involving mixed disulfide bonds were reduced and solubilized when extracellular glutathione penetrated the ruptured cell. Comparisons between normal RBC and vitamin E-deficient RBC suggest that vitamin E has little effect on the inward diffusion of extra-cellular H(2)O(2). Vitamin E apparently interacts with different oxidant species derived from intracellular H(2)O(2) in preventing lipid peroxidation and the sulfhydryl group oxidation leading to hemolysis.

Animals↗
PubMed1977

The trachea and cuff-induced tracheal injury. An experimental study on causative factors and prevention.

The effect of a large tracheal tube cuff on the rabbit tracheal mucosa was investigated by phase contrast microscopy and scanning (SEM) and transmission (TEM) electron microscopy. The tube was left in the trachea for 15 min. The cuff was either uninflated or inflated to a cuff-to-tracheal wall pressure (C-T pressure) of up to 100 mmHg. The uninflated cuff caused superficial damage to the epithelial lamina over regions where a cartilage was situated. When the cuff was inflated, it resulted in an increase of the mucosal damage, the extent of which was directly related to the pressure in the cuff. This took the form of both widening of the injured areas and penetration of the damage to deeper regions. At a C-T pressure of 100 mmHg the damage involved almost the entire mucosa and only small unaffected mucosal regions remained. At this stage it appeared as if the basement membrane had also begun to disintegrate. It is well known that a small cuff easily causes deep ulceration in the mucosa overlying the cartilages. From this investigation it was concluded that a large cuff causes the same type of ulceration if 1) the cuff wall is not sufficiently thin and pliable, and 2) if the cuff is overinflated enough to dilate the trachea to a diameter exceeding the cuff-diameter. At that moment there will be circumferential tension in the cuff and the sealing physics of the large cuff will become the sealing physics of a small (high pressure) cuff. A large cuff, properly handled, is more benign to the trachea than a small cuff. In order to avoid overinflation of the large cuff, the intracuff pressure (= C-T pressure) should always be measured by means of a four-way stopcock and an aneroid manometer. In the case of extended periods of mechanical ventilation with a high airway pressure, the resulting tracheal diameter at the cuff site should be checked radiographically.

Animals↗
PubMed1977

Effect of ethyl alcohol on sympathetic nerve cells in cultures.

Sympathetic chain ganglia of newborn rats were cultured in Rose chambers and their structure was registered, examined and photographed with a phase contrast microscope. When 0.5% (v/v) (86 mM) ethanol was present in the culture medium from the start of culture, the nerve cell bodies appeared similar to those in control cultures for at least a week and there was a normal outgrowth of a nerve fibre network. Higher concentrations had a progessively deleterious effect, 1% (171 mM) ethanol causing the appearance of degenerating cells and 2% (343 mM) ethanol killing all the nerve cells in 4 days. Some nerve cells survived 4 days in the presence of 1.5% (275 mM) ethanol in the culture medium, although most cells died in 2 days. When ethanol was added to cultures grown for 7 days in a control medium, concentration of 0.5% ethanol in the medium had no apparent effect, while most nerve cells died within a week in 1% ethanol, and all cells were dead already after 24 hours in 2% ethanol. It is concluded that ethanol exhibits a remarkably low toxicity towards living nerve cells.

Animals↗
PubMed1977

Combined Nomarski interference contrast and immunofluorescent study of neuropathological specimens: CSF sediments and paraffin embedded brain tissues.

The direct immunofluorescent technique may be easily improved by the use of the Nomarski optics. This contrast allows accurate identification of fluorescent CSF cells and structures in formalin fixed paraffin embedded brain tissues; in the latter, the combined optical procedure is fruitfull in order to avoid fluorescent artifacts misinterpretation. Furthermore, it is emphazised that the conditions in which routine neuropathological specimens are removed and stored usualy does permit the application of the immunofluorescent technique.

Brain↗
PubMed1975

Morphologic and functional characteristics of bone marrow macrophages from imferon-treated mice.

The iron storage macrophage has been isolated from the marrow of Imferon-treated mice and studied in vitro by morphologic, histochemical, and functional tests and isotope labeling techniques. These macrophages on stained preparations are large, many times binucleate cells (up to 150 mu), and show Prussian blue reactivity. In Epon-embedded, stained thick sections they contain elongated narrow basophilic inclusions. These macrophages are actively phagocytic and pinocytic; histochemical studies show that these cells are rich in acid phosphatase, nonspecific esterase, and PAS diastase-resistant activity. Iron storage macrophages do not incorporate the 3H-thymidine. The electron microscopic appearance of this macrophage shows that the cell has ferritin free in the cytoplasm and several types of cytoplasmic granules: those with large quantities of electron-dense ferritin and/or hemosiderin (type A), elongated granules (type B) with moderately electron dense homogeneous matrix and some ferritin at the periphery, and granules with heterogeneous content (type C). The above findings demonstrate that the iron storage cell is a mature macrophage which contains hydrolases, ferritin, and a unique population of cytoplasmic granules which are lysosomal in nature. There is some evidence to suggest that the unusual lysosome (type B granule) occurs after macrophages have ingested erythrocytes.

Acid Phosphatase↗
PubMed1975

Recognition by pregnancy serums of non-HL-A alloantigens selectively expressed on B lymphocytes.

A group of alloantibodies are found in pregnancy sera which react with antigens present on B lymphocytes and monocytes but are not detectable on the vast majority of unstimulated T cells. This specificity distinguishes them from HL-A antibodies which react with both cell types. They were readily recognized through indirect fluorescent antibody analysis by employing the combination of B-cell lymphoid lines and normal peripheral blood T cells. Different sera gave a variety of patterns of reactivity with a panel of 11 lymphoid lines. Similar differential patterns were also observed with normal B cells from different individuals particularly after concentrating the B cells. The antibodies were also cytotoxic to B cells and this procedure gave parallel results to the fluorescence method. The pattern of reactions obtained indicated a very heterogeneous system similar to that for HL-A. Special study of certain of the sera provided evidence that the lymphocyte-defined determinants of the mixed lymphocyte reaction system were involved. For convenience the term HL-B has been employed for these antigens.

Antibody Specificity↗