The role and immunophenotypic characteristics of myofibroblasts in liver of sheep naturally infected with the lancet liver fluke (Dicrocoelium dendriticum).

The main objective of our research was to examine the role and immunophenotypic characteristics of myofibroblasts in sheep liver naturally infected by the lancet liver fluke (Dicrocoelium dendriticum). In the reported study we analyzed liver samples from 20 adult sheep, 14 infected animals and 6 controls. The liver samples were fixed in 10% buffered formalin, and routinely processed and stained using hematoxylin eosin, the periodic acid-Schiff and Masson-Goldner trichrome methods. The immunohistochemical examination was carried out by the streptavidin biotin (LSAB2) method, using antibodies for α-smooth muscle actin (α-SMA), desmin and vimentin. The histopathological examination revealed liver fibrosis in 6 out of 14 (42.9%) analyzed samples, while different forms of cholangitis were observed in the remaining 8 out of 14 (57.1%). The expression of α-SMA was proven in perisinusoidal hepatic stellate cells, portal/septal myofibroblasts, and interface myofibroblasts. The degree of α-SMA expression and the number of α-SMA immunopositive cells were the most intensive in the liver with fibrosis. Desmin expression in all liver samples of infected sheep was confirmed in hepatic stellate cells and smooth muscle cells. The hepatic stellate cells, portal/septal myofibroblasts, and interface myofibroblasts reacted as vimentin positive cells. In the liver without fibrotic changes hepatic stellate cells and smooth muscle cells were desmin positive. The obtained results suggest that all populations of myofibroblasts, especially hepatic stellate cells, play an important role in the increased extracellular matrix formation during parasitic liver fibrosis in sheep naturally infected with D. dendriticum.

Antioxidant enzymes activities and plasma levels of oxidative stress markers in B-chronic lymphocytic leukemia patients.

PURPOSE: Overproduction of reactive oxygen species (ROS) intermediates above the functional capability of cellular antioxidants may result in instability of important macromolecules and represents the molecular basis of many diseases including inflammation processes, cardiovascular alterations, cancer etc. The purpose of this study was to determine plasma level of superoxide anion, hydrogen-peroxide and malondialdehyde (MDA) as markers of oxidative stress and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) as antioxidant enzymes in B-chronic lymphocytic leukemia (B-CLL) patients. METHODS: The study included 29 untreated B-CLL patients in stage A, and 21 in stages B and C, classified according to the Binet system; 31 healthy volunteers formed the control group. After centrifugation of heparinized peripheral blood, plasma levels of all investigated parameters were determined using spectrophotometric methods. RESULTS: Plasma CAT activity was increased in B-CLL patients compared with control subjects; also, progression of disease was related with significantly higher plasma activity of CAT. Also, B-CLL patients showed significantly higher plasma concentration of MDA compared with controls. No statistically significant differences of superoxide anion and hydrogen peroxide as well as plasma activity of SOD and GPx between the tested groups were noted. CONCLUSION: Increase of CAT activity in B-CLL patients indicates that there is stimulation of the antioxidant enzyme system, while the increase of MDA concentration shows increased lipid peroxidation level. According to these results it could be concluded that an imbalance exists between oxidants and antioxidants in the plasma of B-CLL patients.

[Diagnostic criteria in asthma of children]. / Kriterijumi za procenu oblika bronhijalne astme kod dece.

Actual diagnostic sriteria are represented by a large spectar of data proposed by certain authors, so generally accepted protocole does not exist for similar clinical states i.e. asthmatic bronchitis, recurrent bronchitis and bronchial asthma in childhood, there is a different diagnostic terminology. Our clinical experience, in accordance to the work of Kubos et all., for diagnosis of bronchial asthma the following criteria are needed: 1. general characteristics, 2. immunologic factors and 3. nonspecific precipitating factors. In the primary classification tovextrinsic (atopic), intrinsic (infective) and mixed form of asthma, we consider that the mixed form in pediatric population is the most frequent. In the last form of the disease, attacks are provoked by acute viral respiratory infections, while the role of allergy, metreologic and psychical factors appears by age of children. Classification of asthma on the basis of frewuency of crises, regardless of season, maw be made in the following manner: 1. light form (less than one crise per month), 2. moderate from (about one crise monthly), 3. severe form (several crises during the month) and 4. very severe form (with permanent symptoms). Beside presented criteria, we used data of personal and familly history, climate conditions of environment, as well as the results of previous treatment in climate stations.

Comparative studies on Ca2+- and Mg2+-binding of sarcoplasmic reticulum and chromaffin granule membranes.

The binding of calcium and magnesium ions to sarcoplasmic reticulum (SR) and chromaffin granule membranes was comparatively studied. The SR membranes are equipped with equal quantities of binding sites for both calcium and magnesium ions. The binding sites in presence of ATP combine specifically with calcium ions, while in the absence of ATP the binding sites react unspecifically with both ions. The trace amount of magnesium present in the SR membranes preparations is sufficient to drive ATP dependent calcium accumulation. Magnesium binding, however, is not affected by ATP. The chromaffin granule membranes bind calcium and magnesium in the same concentration range as observed for the SR membranes. Magnesium binding, however, is two times higher than that of calcium binding. In the absence of ATP, calcium and magnesium ions mutually compete. In the presence of ATP, magnesium binding values increase 3-5-fold, while the calcium binding isotherm remains unchanged. The appreciable contribution of the lipid phase to ions binding has been investigated, but was found to be of minor importance in this study.