Eksperimentalna meditsina i morfologiia最新文献

In order to establish the polarizing microscopical characteristics of collagen in preserved dura mater transplants and in controls, a study was performed. Attempt was made for an intrpretation of velocity of collagen rehydratation by means of data of total anisotropy. The results show a faster rehydratation of collagen fibrils in control (unpreserved) dura mater. Changes in the velocity of rehydratation of collagen fibrils in lyophilized dura mater were connected with structural changes during lyophilization. The most appropriate period of time for rehydratation of lyophilized dura mater transplant was determined from the results of the polarizing microscopical study.

The contents of glucagon in insulin substances ("Pharmachim" Ltd.) is determined in accordance to the needs of pharmaceutical production. The middle quantitative values and standart deviation are specified. Nevertheless that monocomponent and bovine conventional insulin substances pertain to groups of different purity they exibit the highest purity. Bovine conventional insulins exibit the greatest variability, while monocomponent insulins are destinctively homogenous. Single-peak insulin substances exhibit less purity, but this group is more homogenous. The middle quantitative value is within the admissible limitations. Porcine conventional insulins have high contents of glucagon as well as high values of standard deviation.

The authors studied light- and electronmicroscopically the lungs of 20 rats after experimental burns in closed space. Twenty one histological parameters were evaluated. Two mechanisms of quickly developed fatal outcome were established--asphyxia and acute injury of shock lung. Electronmicroscopically there was an increased secretion of surface active materials and degenerative changes in the alveolar epithelium and capillary endothelium. Carbon particles found in the upper respiratory tract were considered as signs of vitality.

The early ultrastructural changes in type 2 pneumocytes (PN2) as a result of burn and endotoxic shock in rats and rabbits were studied. Stereotype morphological damages in PN2 were established. Differences between experimental models were quantitative and depend mainly from the severity of shock and animals species. Morphofunctional heterogenity of PN2 population leads to the appearance of three groups of PN2: 1) PN2 with degenerative changes; 2) PN2 with "stress" hyperactivity and exocytosis of lamelar bodies; and 3) PN2 with increased number of lamelar bodies. Disturbances of lamelar bodies morphogenesis (conglomerates, giant lamelar bodies) as well as lamelar bodies formation by alternative way - directly from rough endoplasmic reticulum were observed. The predominant part of the described PN2 lesins were adaptive in character.

The aim of the present study was to elucidate the correlation between the Renin secretion and increased Plasma Calcium concentration and the role of Calmodulin in this process. Plasma Renin activity was determined radioimmunologically in 31 white rats, that were grouped as follows: group I - 7 controls loaded for 6 days perorally with 0.5 ml/200 g b.w. glycerin and injected i.m. for 6 days with 0.1 ml/200 g b.w. with 0.9% NaCl; group II - 8 rats, treated for 6 days with Tachistin 0.0025 mg/200 g b.w., dissolved in glycerin 0.5 ml/200 g b.w.; group III - 5 rats, treated with Tachistin 0.005 mg/200 g b.w. in the same manner; group IV - 5 rats injected i.m. with Chlorazin 0.5 mg/200 g b.w. for 6 days; group V - 6 rats, loaded with double dose Tachistin and with Chlorazin 0.5 mg/200 g b.w. for 6 days. Blood samples were taken intracardially on the seventh day from the beginning of the experiment and were analyzed with kits of Sorin-Biomedica-Italy. Our results suggest that the hypercalcemia induced by Tachistin caused a dose-dependent increase of PRA and Ca-Calmodulin complex is the dominant second messenger of Renin secretion.

The upper extremity H-reflex was investigated in healthy children, aged from 3 to 15 months. The electromyographic reflex responses of m. abduct or digiti min. and m. flexor carpi uln. were registered after electric stimulation of n. ulnaris. We constructed the curve of restoration of H-reflex after application of a couple of stimuli with equal duration and intensity, but over increasing intervals. We established changes in the excitation of H-reflex, obtained from m. flexor carpi uln., by increasing of the interval between the conditional and test stimuli. In the interval of 5 ms maximal facilitation was registered, while in the interval of 20 and 30 ms-maximal inhibition. In children aged from 3 to 9 months with persisting H-reflex in m. abductor digit min. we established possibility for its complete inhibition after application of a couple of stimuli with interval of 20 ms. In children aged from 9 to 15 months with vanished H-reflex in m. abductor digiti min. possibility for its obtaining was established after application of a couple of stimuli with interval of 5 ms. Quotation is made of evidences in favour of the hypothesis for the functional character of the disappearance of H-reflex in the small muscles of the arm in the first year of life of the children.

The morphological investigation in an experimental model of lead (Pb) encephalopathy (according to the method of A. Pentschew, 1966) is presented. Electron microscopy-dense inclusions are found out in the nuclei and cytoplasm of astrocytes and in some ependyma cells in the investigated cortical and subcortical (paraventricular) structure of the brain and spinal cord. This confirms the direct toxic action of Pb on these structures and proves their participation in pathogeneses of the developing encephalopathy. The established inclusions in the ependyma and the data about a disturbance of the blood-brain barrier give a reason to be proposed the possibility for a penetration of Pb in the nervous system not only through a blood but also through a cerebrospinal fluid way.

A fructose-1,6-diphosphate preparation was tested for hepatoprotective activity through biochemical and morphologic studies in experiments on Wistar rats sustaining D-galactosamine- and paracetamole-induced hepatotoxicity. Findings indicated the modeled hepatic lesions to be readily reproducible, to simulate some characteristics of human liver pathology, and to be suitable for testing substances expected to have hepatoprotective action; intraperitoneal administration of fructose-1,6-diphosphate at a dose of 1000 mg/kg body weight proved moderately protective against liver damage by D-galactosamine; the benefit observed concerned mostly dystrophic and inflammatory changes in the liver; in a number of cases, correlation was noted between biochemical serum parameters and pathomorphologic liver alterations.

By application of the two-component test PWC170, the changes in the heart rate (HR) and the difference in the duration of the minimal and maximal cardiac cycles (SAr), were studied. The indices (HR and SAr) were recorded by electrocardiography prior to the test (initial values), during the three-minute pause between the two loadings and in the three-minute recovery period following the second loading. It was found that SAr in the pause after the first loading with lower intensity of the test was more markedly expressed with respect to its initial values, while in the recovery period after the more intensive second loading of the test it was not only less expressed but in a number of cases did not reach the initial values. It was assumed that the relationship between the expressed in each moment influences of the vagal and sympathetic neuroregulatory mechanisms of the heart was significant for the expression of the observed rhythmic fluctuations.

Our previous investigations have demonstrated that saline extract of Arum maculatum contains lectin (sperm agglutinin) which agglutinates human ejaculated spermatozoa of the type tail to tail and head to tail. By means of speed liquid chromatography (Mono S XP 5/5) eight fractions (I-VIII) were obtained. The sperm-agglutinating activity of the fractions was investigated against frog testicular spermatozoa and testicular and epididymal spermatozoa of man, rabbit, rat and mouse. The fractions did not agglutinate frog spermatozoa. Fraction I agglutinated rabbit, rat and murine spermatozoa; fraction II-rabbit and rat spermatozoa; fraction VII-only human spermatozoa, and fraction VIII-human, as well as animal spermatozoa. The fractions III, IV, V, VI had no sperm-agglutinating activity. These data could be explained by the assumption that the differences in the sperm-agglutinating activity of the fractions are due to isoforms (called also isolectins) of the phytospermagglutinin, contained in the saline extract of Arum maculatum.