Eksperimentalna meditsina i morfologiia最新文献

Problem-solving case approach is an effective method for teaching clinical concepts. This method makes medical students be aware of the significance of Biochemistry for the clinical practice. The students are stimulated to study basic biochemical principles. The complete text of a problem case on galactosemia is presented. This case, usually given to the students during the final seminar on carbohydrate metabolism reflects a real situation, in which the student feels responsible to make decisions. He has to make the diagnosis and prescribe a treatment. The student's actions are assessed and commented. The students took a great interest in that problem case and that shows that it is possible and necessary even in the second preclinical year to joint the theoretical principles with the future clinical practice.

A new in vitro radioreceptor assay method for determining the biological activity of insulin substances is put forward. This method is designed mainly to serve the purposes of practice. It perfectly substitutes the biological, expensive labour-taking and slow pharmacopoeial method. It is reproducible, does not depend on the season and reduces the species differences to minimum by using a mixture of bovine and porcine insulins (Forth International Standard) as the source of unlabeled insulin. The rat liver membrane receptors (preparations) retained their insulin-binding ability up to 10 months, when stored at -18 degrees C-(-)20 degrees C. By means of this method the biological activity in different insulin preparations is established. It is found that this activity is highest in the monocomponent insulin substances, followed by the single-peak insulins and it's lowest in the conventional insulins.

The contents of pancreatic polypeptide in insulin substances ("Pharmachim" Ltd) is determined in accordance to the needs of pharmaceutical production. The analysed insulin substances pertain to groups of different purity. The results, showing distribution of middle value of pancreatic polypeptide are discussed.

The liver microsomal content of cyt. P450 and b5 and activities of selected mixed-function oxidases were compared following phenobarbital (PB)- and 3-methylcholantrene (MC) induction and acute intoxication with carbontetrachloride (CT). PB increased the content of P450 and the activities of both NADPH-cytochrome c reductase and benzphetamin demethylase. MC increased only the content of cytochrome b5. CT after 4 hours damaged selectively the liver monoxidase components: 1. the activity of NADPH-cytochrome c reductase and the content of b5 were not changed in the three groups; 2. the content of P450 was decreased differently: more sensitive to the destructive effect of CT was the PB-inducible P450. Most resistant was the MC-inducible P450; 3. MC decreased the benzphetamin demethylation in control- and PB-microsomes in lower degree than the content of P450. The relative high rates of the benzphetamin demethylase after CT by PB-microsomes was explained by increased activity of NADPH-cytochrome c reductase in this group. The selective damaging effect of CT on P450 was interpreted by complex of local factors: metabolizing of CT to CCL3, lipid peroxidation, phospholipid microenvironment, pO2, antioxidants concentration, activity of heme degrading enzymes.

Peri-insular lymphoid infiltrations were observed in nondiabetic C57BL/6J mice. The type of infiltrating cells was determined by direct immunoperoxidase technique. A larger part of lymphoid cells did not show reaction with a goat antimouse IgG Rh conjugate. Intensive hyperplastic reaction and the presence of many immunoglobulin producing cells were observed in the lymph nodes adjoining the pancreas. Probably the observed infiltrations in the pancreas of nondiabetic C57BL + 6J mice were composed mainly of T lymphocytes, belonging to T helper subpopulation.

The morphological characteristics of oligodendrocytes in the lower olivary complex of ground squirrels at various ages were studied by light and electron microscopes. On the basis of an analysis on thick sections, stained with toluidine blue, it was established that nuclei of these cells were smaller and darker in comparison with those of astrocytes. The mean oligodendrocytes, located in perineuronal, perifascicular, perineuronal-perifascicular, interfascicular, perivascular position or freely situated, predominated in the neuropile of the lower olivary complex. Changes in their ultrastructure were investigated during advancement of age and during the process of aging. An increase in the number of heterogeneous dense bodies were found as well as the presence of lipid-pigmented granules with crystal-like brightening. The connection of oligodendrocyte growth with myelin sheath of axons.

Isoproterenol, administered intraperitoneally in rats in a dose of 2 mg/kg of body mass for a period of 20 days, induced myocardial hypertrophy. After its stoppage a period of regression occurred, during which the myocardium recovered practically to its initial state. Complex studies of connective-tissue components (collagen, glycosaminoglycans, total nonfibrillary protein, total protein, structural, glycoproteins), metrometric data-the coefficient R (1 g of myocardium/199 g of body mass) and histomorphological investigations were performed. The same studies were done on rats of a control nontreated group and of experimental groups-on the 0 day. 7th, 14th and 42 day. It was established there was a gradual recovery to normal values of collagen, total nonfibrillary protein and the coefficient R, which were highest on the day 0. Progressive diminution, e.g., normalization of both the connective tissue components and of the volume of myocardial cells was found histomorphologically, in which the changes were mostly manifested on the day 0, as well. The complex studies of the connective tissue with isoproterenol MH proved that the changes of MH in this tissue correlated with the stages of MH respectively its regression.

Studies were carried out on patients with hypertension I and II stages to examine the influence of therapeutic swimming on cerebral activity and heart function. The authors investigated 30 persons (mean age of 48.5 +/- 9.5 years) divided into 2 groups: first--experimental including 20 subjects, who participated in a course of therapeutic swimming (according to our methods) for a period of 4 months and second--control, composed of 10 persons, who did not swim. Electroencephalograms and electrocardiograms were recorded from subjects of both groups before and after 4 months of swimming as simultaneously with this blood pressure was measured several times. The results showed that therapeutic swimming affected favourably brain bioelectrical activity (improved regulation and modulation of the rhythm, reduced dysrhythmia and did not increase the number of pathological waves) as well as cardiovascular system of the examined persons with hypertension of the experimental group as statistically significant lowering of blood pressure was induced, while the investigated parameters showed opposite reactions in the persons of the control group. On the basis of positive changes in the investigated parameters the therapeutic swimming is recommended to be included in the complex the therapy of the persons suffering from hypertension I and II stages.

Data about direct effect of vasopressin (VP) on the central arterial pressure (AP) orientated us to investigate the effect of its local administration in the median eminence (ME) of the hypothalamus in rats. For this purpose VP was administered in ME under micropellet form. AP was measured indirectly on the tail of rats up to 96th hour after operation. After implantation of VP there was an elevation of AP with maximum in the first hour, which was statistically significant (p less than 0.01). Identical manipulation (sham operation) was performed to control the lesion effect. Transitory lowering of AP with maximum in the first hour was also established and it was statistically significant (p less than 0.001), For exclusion a nonspecific systemic effect of VP the same dose was administered in the parietal cortex, during which transitory and short-lasting reaction occurred in the first hour after the operation. The data indicate that the peptide, administered in ME under micropellet form, could induce a longlasting hypertensive effect.