Czechoslovak medicine最新文献

Investigation of 17 children delivered after prenatal examination of amniotic fluid GGT was performed. GGT testing was carried out in the 17th-18th week of gestation. The development of children unaffected by cystic fibrosis was predicted. In all pregnancies, clinically healthy children with normal sweat chloride concentrations were delivered. Our results confirm the advantage of the examination of microvillar enzymes in amniotic fluid in the second trimester as a rather reliable method of fetal diagnosis of cystic fibrosis if it is impossible to use the molecular genetic methods in the first trimester.

The bilayer lipid membrane (BLM) was used to reconstitute the hormonal reception system for insulin. The effect of insulin on both unmodified BLM and BLM modified by rat liver plasma membrane fragments was studied by measuring the viscoelastic parameters of membranes--the modulus of elasticity in the direction perpendicular to the membrane plane, E perpendicular to, and the coefficient of dynamic viscosity, eta. The effect of insulin (in concentration of 10(-10) mol la1) on modified membranes resulted in a much greater (about 30-40%) decrease of E perpendicular compared to that on unmodified BLM. Analysis of the developed model of the membrane showed that in the vicinity of insulin--in the case of the unmodified BLM--and in the vicinity of hormone receptors--in the case of modified BLM--there appeared extensive regions of a changed membrane structure which could cause cooperative changes in the studied viscoelastic parameters of BLM. These changes were considerably influenced by the initial value of the BLM modulus of elasticity, fragment concentration and by the content of membrane cholesterol, which has a strong inhibitory effect. The effect of the insulin antagonist glucagon on modified BLM resulted in opposite changes of the relative value of E perpendicular compared to the effect of insulin.

Most patients with cardiac mass have clinical signs mimicking mitral stenosis. As this tumorous mass carries the risk of obstructing the systemic circulation, the physician must consider the possibility of a cardiac tumour in differential diagnosis. That's why all patients presenting with clinical symptoms and a physical finding of mitral stenosis--even those without a history of rheumatic fever--should have routine echocardiography performed. All patients with a documented mass in cardiac chambers should be treated surgically and without delay, if possible.

The aim of the study was to analyse the type of ECG changes in patients after acute myocardial infarction and to compare them with changes in their physical performance. The authors examined 218 patients with acute myocardial infarction after discharge from hospital. Resting ECG and step-wise graded exercise ECG test on a bicycle ergometer was carried out. The technique of examination was in accordance with WHO recommendations. Statistical evaluation was performed by the Wilcoxon-Mann-Whitney's U-test. The workload in patients showing ECG changes of "transmural" myocardial infarction was not different compared with that of persons with "non-ransmural" lesion (70.00 W versus 71.7 W). When evaluating the relation between the site of ECG changes and the workload, the authors found that the lowest tolerated workload was in cases where ECG changes suggested an extensive damage to the myocardium (53.5 W, p less than 0.05). The authors conclude that the extent of ECG changes after myocardial infarction is a better marker of the level of impairment of physical performance than patient classification to Q or non-Q types.

This paper presents the results of a study focussed on the locomotor apparatus and on the biological systems integrated in it. This study was carried out by a large group of workers in the Institute of Anatomy in Prague, with close and mutual interweaving of their contributed works. The review demonstrates the ontological advancement achieved in the fields of morphology and development of these locomotor structures. From descriptive studies it proceeds towards experimental works specially oriented to understand developmental mechanisms and the causality of their origin, within the context of the most recent advancements in developmental morphology. Even individual applications in clinical practice, which might arise, have been pointed out. The whole set of works having been referred to, from which only a fraction necessarily limited due to the length of this publication could be cited, also demonstrated here the possibilities of employing knowledge obtained about the locomotor apparatus of the limbs in further research concerning the more generalized aspects of the mechanisms of development and their regulations, down to their molecular biological level.

The study of bilirubin photochemical degradation in the presence of riboflavin has shown that, in this case, the primary process is photooxidation during which riboflavin acts as a receptor and bilirubin as a donor of electrons. The reaction proceeds under anaerobic conditions in an equilibrated manner, under aerobic ones as a catalytic process during which the catalyst, i. e., riboflavin is regenerated. The primary intermediate product is biliverdin in vitro, later this is further broken down. For the purpose of studying the mechanism of this process liquid chromatography and computerized technique based on solving nonlinear differential equations have been used. It appears that during phototherapy in the newborn infant there develops a decrease of the blood level of riboflavin reaching up to hypovitaminotic values and a transient biliverdin level elevation. Oral riboflavin administration may maintain this level within physiological range and at the same time shorten the necessary duration of phototherapy. In severe cases of hyperbilirubinaemia a shift of the ratio between flavin-adenin-dinucleotide and free riboflavin, as compared to the physiological state, has been recorded. The results of this work are discussed in the light of our current knowledge concerning the mechanisms of bilirubin breakdown during prototherapy.

Using 36 monocyte samples, an assay was performed with 42 antimonocyte sera, by means of a micromonocytotoxic test, the results of which were evaluated statistically through computation of the correlation coefficient r 6 specific monocyte antigens were detected and labelled MoP-1 to MoP-6, their frequencies varying from 5.58% to 41.67%. These antigens belong probably to one single system. Among the individual samples of monocytes no more than 2 of these antigens could be demonstrated per sample, in 11 of the 36 no antigen could be revealed at all. The difficulties of these studies are pointed out, they are due mainly to the instability of antimonocyte sera which often lose their activity during storage in a frozen state.

The authors have summarised their experience with short-term use of a left ventricle assist device (LVAD). Nine experiments were carried out in healthy calves. A polyurethane pump of their own design, placed extracorporeally, was used. Its in-flow cannula was placed in the left atrium, the outflow one in the initial segment of the descending aorta. The LVAD was operated for a period of 5 days. Fourteen days after its disconnection, the animal was sacrificed and both the bypass system and parenchymal organs were examined. No surgical complications were observed during the experiments. Macro- and microscopical pictures showed minor infarctions in the renal tissue which, however, did not impair renal function. The findings in other organs were related to anaesthesia, the operative procedure and way of animal sacrificing. The experiments have proved the safety of the bypass system used over a short period and, consequently, its potential for future clinical application.

In human lymphocytes three dipeptidyl peptidases were discovered in our laboratory. For a correct demonstration of activities of these enzymes discriminating substrates must be used. Dipeptidyl peptidase IV (DPP IV) is revealed with Gly-Pro-4-methoxy-2-naphthylamide (Gly-Pro-MNA) and Fast Blue B (FBB). It is present in the surface membrane of about 40% lymphocytes of the peripheral blood. Only T-lymphocytes bear the reaction. Reacting lymphocytes belong predominantly to OKT4+ subset. Some OKT8+ lymphocytes also react. With more sensitive substrates (Lys-Pro-MNA, Phe-Pro-MNA and Ala-Pro-MNA) a co-reaction of DPP II was demonstrated "in situ" and in zymograms. In haemoblastoses a positive reaction in cells indicates their derivation from the T-lineage of lymphocytes. A negative reaction does not exclude a T-cell malignancy, however. A decreased number of DPP IV positive lymphocytes in the peripheral blood indicates a diminished immunocompetent potential of T-cells, e.g. immunodeficiency in patients with malignant lymphoma, gastric and colocrectal carcinoma, AIDS, etc. DPP II demonstrated with Lys-Ala-MNA occurs in about 60% of lymphocytes belonging to T and B subsets. It is localized in lysosomes. Although Lys-Pro-MNA is a more sensitive substrate a co-reaction of DPP IV must always be considered. Patients with chronic B-lymphocytic leukaemia displaying a high number of DPP II+ cells usually have a worse prognosis. DPP I assessed with Gly-Pro-MNA and nitrosalicylaldehyde occurs in about 20% of T and B lymphocytes. The number of positively reacting cells increases after corticosteroid therapy. The influence of the treatment on the activity can be shown very well in histograms of DPP I activity measured by computer-assisted microfluorometry.