PubMed Health⌕ Search

Biomedical subjects

M Brozman

Publications and source records attributed to M Brozman.

At least 19 recordsLinked to original sources
PubMed1992

[Prenatal virus infections and orofacial clefts].

A potential teratogenic activity of virus infections caused by the viruses of rubella, influenza, parotitis, hepatitis B, cytomegalovirus and the Epstein-Barr virus was investigated. Specific antibodies against these viruses were examined serologically in children with orofacial clefts and in their mothers and the results were compared with those obtained in control children and their mothers. Different micromethods were used in performing the examinations (ELISA, RIA, NIR, KFR, HIT). Evaluation of the results and their statistical processing supports the assumption that prenatal infection may have occurred in the series studied induced by the viruses of influenza, rubella, cytomegalovirus, and possibly also by the Epstein-Barr virus. No association with the viruses of parotitis and hepatitis B was established. (Tab. 5, Ref. 36.)

Antibodies, Viral↗
PubMed1979

Effects of feeding a single daily meal and of changes in lighting schedule on the circadian rhythms of oxidoreductases in the rat gastric mucosa.

The present paper investigated the effect of restricted feeding (11.00 to 13.00 h) by a single daily meal upon the activity of various oxidoreductases of the rat gastric mucosa (SDH, alpha-GPDH, LDH, NADHTR), which at ad libitum feeding under normal lighting conditions with a dark night were shown to have distinct circadian activity variations related to the rat's nocturnal food intake preference (Zaviacic and Brozman 1978a). 1st part of the animals received food in 2-h-period by natural daylight (natural lighting conditions), the 2nd part at the same period of time but in the dark (lighting conditions reversed to natural). Checking the consumption of food, we found the animals to become adapted to the new time of food intake beginning with the 6th experimental day. The circadian rhythm of enzymes was examined on days 69, 83, 97, and 104 of limited feeding under the defined lighting schedule, at 06.00 h, 12.00 h, 18.00 h, and 24.00 h in groups of 5 animals. Synchronization of the highest dehydrogenases activities (particularly of SDH) with the time of restricted feeding was seen to develop in the gastric mucosa of the rat. The synchronization effect was more pronounced in the animals which received their food in the dark (and here even more in male than in female). The effect of light during food intake was found to be rather interfering with the development of synchronization of dehydrogenase activities with the time of food intake, and the influence was again more marked in male than in female. The time of food intake was at the feeding schedule restricted to daytime intake the main synchronizer for the circadian rhythm of oxidoreductases of the gastric mucosa of the rat, with the highest daily activities recorded around the feeding time and the lowest activities at night, which is the direct opposite of the circadian rhythm of the same enzymes determined in rats fed ad libitum under normal lighting conditions with a dark night.

Animals↗
PubMed1979

[Immunofluorescence investigation of formol-paraffin material].

Immunohistochemical methods were employed for the investigation of bioptic and necroptic material fixed in formol and embedded in paraffin after it had produced very little or no fluorescence at all in the use of routine immunofluorescence techniques. Partial digestion with pepsin or trypsin or both enzymes in succession mostly facilitated positive immunohistological reaction. This particular procedure gives more scope to the methodological possibilities of histological material examination in that it offers an opportunity for the immunohistological investigation of even old material not specially preserved for immunohistological purposes but routinely fixed in ordinary formol. The simplification adds general availability to the method.

Fixatives↗
PubMed1979

Morphologic changes in the gastric mucosa of rats after administration of N-methyl-N'-nitro-N-nitrosoguanidine. Electronmicroscopic study.

Electron microscopic findings of the effects of exposure to the cancerogenic substance N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) upon the gastric mucosa of rats are presented. MNNG was administered in drinking water at a concentration of 83 mg/l over a period of eight weeks. The resulting findings included occurrence of myelin figures in membrane structures of epithelial cells, occasional disappearance of nuclear membrane, numerous intranuclear cytoplasmic pseudoinclusions, and increased number of perichromatin and interchromatin granules and of nuclear corpuscles. Narrowing of the layer of peripheral condensed chromatin and broadening of the layer of dispersed chromatin were frequently observed. In the cytoplasm of epithelial cells, production of autophagous vacuoles was detected in differentiated types of cells, the presence of great amount of polysomes and profiles of rough endoplasmic reticulum diversely deformed was seen in the undifferentiated neck cells. These cells presented a marked proliferative activity. Some of the changes described in the nuclei of epithelial cells were also observed in different mesenchymal elements in the lamina propria mucosae. The demonstrated changes are indicative of both regressive and progressive effects of the cancerogen used in our experiment.

Animals↗
PubMed1979

[Morphology of systemic anaphylactic reaction in rabbits to bovine serum albumin and ferritin. I. Manifestations of the reaction after antigen administration: laboratory, macroscopic and optical microscopic findings].

A report is presented on systemic anaphylactic reaction [SAR] of rabbits to bovine serum albumin and ferritin. Active anaphylactic sensibilization with a high yield of sensibilized animals was achieved by administering antigens to rabbits aged a few hours up to 3 months. Tre rabbits showed no presence of precipitins in the circulation, but there were reagins against bovine serum albumin or ferritin. There were various types of SAR activity. Macroscopic findings showed acute emphysema and signs of right heart overload. Apart from acute pulmonary emphysema, histology showed occasional bronchospasm and certain manifestations of RES activation as there was evidence of oedematous infiltration of the peribronchial and perivascular spaces. The above morphological findings cannot as yet be regarded as pathognomonic for SAR.

Anaphylaxis↗
PubMed1978

Influence of autolysis on rat gastric endocrine cells. Histochemical and electron microscopical study.

In the present study histochemical parameters of the rat gastric endocrine cells were followed up in the course of 24-h autolysis, and their ultrastructure was studied during autolysis lasting for 60 min. The autolysis occurred at 37 degrees C. In the light microscope, with the histochemical methods applied, only EC, ECL and G cells could be identified during the one-hour autolysis. With the autolysis proceeding for 6 and 12 h, only argyrophil method according to Grimelius (1968) enabled visualization of gastric argyrophilic cells. After 24 h of autolysis, none of the methods applied (not even the Grimelius method) proved to be adequate for successful demonstration of the gastric endocrine cells. In the course of 60-min autolysis, electron microscopic examination provided identification of the EC, ECL, AL, D1, and G cells with the characteristical ultrastructural appearance of granules. The granules of the endocrine cells (G cells included) were found to be considerably resistant to autolysis. The effect of 60-min autolysis did not induce granule "emiocytosis" or dissolution of granule content. Autolysis exceeding five minutes resulted in damage of the mitochondria of different degrees and in dilatation of the profiles of endoplasmic reticulum (particularly in G and AL cells). The results obtained in the present study demonstrate the feasibility of in vitro experimental stimulation since the endocrine granules have proved to be resistant to the effects of simultaneously developing autolysis.

Animals↗
PubMed1978

Experimental ultrastructural study on stimulation of the rat gastric endocrine cells. In vitro distension of the stomach by air inflation.

The effect of distension of the stomach by air (in vitro) upon the ultrastructural picture of gastric endocrine cells in rats starved for 72 hours was investigated. Distension of the stomach by air in vitro, lasting for 5, 10, 15 and 20 minutes, resulted in massive dissolution of gastrin granules that had accumulated in the course of starvation. In AL, D1, EC and ECL cells distension of the stomach by air failed to induce dissolution of granular content or release of granules by any other mechanism. In AL and D1 cells accumulation of secretory granules caused by starvation was observed, the ultrastructure of EC and ECL cells remained unchanged both under the effect of starvation and distension. Dilatation of endoplasmic reticulum profiles as well as other changes on some cell organelles observed on endocrine cells after distension of the stomach by air in vitro are due to the effect of autolysis.

Air↗
PubMed1978

Nephrotoxic and pneumotoxic antibodies and their acute action on lungs. III. Organ localization of antibodies after experimental administration of lethal doses.

Experimental intravenous administration of large doses of heterologous anti-glomerular and anti-lung antibodies induces acute exsudative haemorrhagic changes in the lungs resulting in death of the experimental animals. The specific localization of these antibodies labelled with radioactive isotopes of iodine and administered using the paired-isotope technique with radioiodinated normal IgG, displayed high values in the lungs, liver and kidneys. Pulmonary changes developing after administration of the same dose of anti-glomerular antibodies into the left heart ventricle are of lesser extent and the animals survive. On this mode of administration, the specific localization of antibodies presents lower values in the lungs, whereas the values in the kidneys and liver are approximately the same as seen after intravenous administration. Antibody localization in the kidneys and liver is facilitated by the morphologic structure of the capillaries, whereas in the lungs a direct transendothelial transfer must be considered, since in this organ capillary endothelium forms a coherent layer. Attention is being drawn to the high specific localization of antibodies in the liver and to the potential effect of these antibodies on the liver.

Animals↗
PubMed1978

Immunohistochemical analysis of formaldehyde- and trypsin- or pepsin-treated material.

Immunohistochemical studies of paraffin sections of formaldehyde-fixed material and formaldehyde-fixed cryostat sections treated with trypsin or other enzymes were undertaken. Formaldehyde treatment resulted mostly in partial or total loss of antigenicity, as visualized by fluorescent antibody technique in tissue sections. The digestion of sections with trypsin resulted usually in total or partial restitution of antigenicity, previously altered with formaldehyde. This effect is suggested to consist primarily in breaking formaldehyde-induced intermolecular cross-links. Restitution of antigenicity altered by formaldehyde can also be achieved on using pepsin or other proteolytic enzymes, or by some other technique. When the effect of one enzyme proves insufficient, it can readily be complemented by the action of another enzyme applied subsequently. Mild trypsin treatment preserves well the morphological structure of most tissues.

Animals↗
PubMed1978

Circadian rhythms of oxidoreductases in the rat gastric mucosa. Histochemical study.

Examination of selected oxidoreductases (succinate dehydrogenase, mitochondrial glycerol-3-phosphate dehydrogenase, lactate dehydrogenase, NADH tetrazolium reductase) in the rat gastric mucosa revealed diurnal fluctation of enzyme activities with the most marked manifestation in succinate dehydrogenase. The maximum enzymatic activity found at 18.00 h and 24.00 h) points to the highest oxidoreductase capacity in the parietal cells just at the time when a rat usually expresses spontaneously the highest interest in food intake. The high activity of succinate dehydrogenase and other enzymes at that time is very likely the expression of a "fixed" metabolic adaptation of the parietal cells to the elevated production of hydrochloric acid, in connection with its role in the digestion of food in the stomach. The low enzymatic activity of most rat parietal cells during the day may represent the picture of "a resting afunctional".

Animals↗