Lithium-pilocarpine status epilepticus (SE) resulted in delayed changes of single cortical in terhemisperic (transcallosal) responses in immature rats. Low-frequency stimulation inducing depression and/or potentiation was studied to analyze possible dynamic changes in cortical responses. Status was elicited in 12-day-old (SE12) or 25-day-old (SE25) rats. Control siblings received saline instead of pilocarpine. Interhemispheric responses were elicited by stimulation of the sensorimotor region of the cerebral cortex 3, 6, 9, 13, or 26 days after status. A series of 5 biphasic pulses with intensity equal to twofold threshold were used for stimulation. The interval between pulses was 100, 125, 160, 200 or 300 ms, eight responses were always averaged. Peak amplitude of the first positive, first negative and second positive waves was measured and responses to the second, third, fourth and fifth pulse were compared with the first one. Animals after status epilepticus as well as lithium-paraldehyde controls exhibit a frequency depression at nearly all the intervals studied. An outlined increase of responses in SE rats in comparison with the controls three days after SE stayed just below the level of statistical significance. In addition, animals in the SE12 group exhibited potentiation of responses at this interval after SE. With longer intervals after SE, the relation between SE and control animals changed twice resulting in a tendency to lower amplitude of responses in SE than in control rats 26 days after SE. Rats in the SE25 group exhibited higher responses than controls 13 days after status, but this difference was not present at the longest interval after SE. Low-frequency stimulation did not reveal increased cortical excitability as a long-lasting consequence of status epilepticus induced in immature rats. In addition, the outlined differences between SE and control rats changed with the time after SE., G. Tsenov, P. Mareš., and Obsahuje bibliografii a bibliografické odkazy
A measuring system evaluating a Point Spread Function generated in an ultrasonographic image by scanning a spherical target was developed. The target is moved in measuring bath filled by water over scanned volume via 3D computer controlled positioning system. A video signal obtained is converted to digital form and analyzed by original software to derive various objective parameters of the imager as follows: Focal areas in both the azimuth and the elevation directions, Ultrasound scanning lines visualisation, Manufacturer preloaded TGC, Width of the scanning plane, Side lobe levels and Amplification uniformity in the azimuth direction. The method was verified by testing 18 different equipments in 282 measurements. Samples of particular measurement results in form of graphical outputs are included. Medical and physiological impacts of this approach are discussed., L. Doležal, J. Mazura, J. Tesařík, H. Kolářová, D. Korpas, S. Binder, J. Hálek., and Obsahuje bibliografii
The relationship between angiotensin II (ANG II) and endothelin-1 (ET-1) is known to be complex; both peptides can initiate and potentiate the gene expression of each other. This pilot study investigated the effects of the AT1 receptor blocker losartan or the direct renin inhibitor aliskiren on mean arterial pressure (MAP) and albuminuria and the renal ANG II and ET-1 levels. 3-month-old male Ren-2 transgenic rats (TGR) were treated either with losartan (5 mg kg-1 day-1) or aliskiren (10 mg kg-1 day-1) for 10 weeks. At the end of the experiment, rats were decapitated and cortical and papillary parts of kidneys were separated. Plasma and tissue ANG II levels were measured by RIA and tissue ET-1 concentrations by ELISA. In all four groups of animals ET-1 levels were lowest in renal cortex and more than 100-fold higher in the papilla. Cortical and papillary ET-1 concentrations in untreated TGR significantly exceeded those of control HanSD rats and were significantly depressed by both drugs. In both strains, papillary ANG II concentrations were moderately but significantly higher than cortical ANG II, TGR exhibited higher ANG II levels both in cortex and papilla as compared to control HanSD rats. Aliskiren and losartan at the doses used depressed similarly the levels of ANG II in cortex and papilla and reduced ET-1 significantly in the renal cortex and papilla below control levels in HanSD rats. Albuminuria, which was more than twice as high in TGR as in HanSD rats, was normalized with aliskiren and reduced by 28 % with losartan, although MAP was reduced to a similar degree by both drugs. Despite similar reductions of MAP and renal ET-1 and ANG II levels aliskiren appears to be more effective than losartan, at the doses used, in reducing albuminuria in heterozygous hypertensive Ren-2 rats., Z. Vaňourková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Recent observations suggest the presence of 20S proteasomes (20S) in the lung epithelial lining fluid. However, the physiological relevance of 20S in the alveolar space and possible contribution to disease processes are unknown. Thus, we evaluated whether extracellular proteasomes could have a pathophysiological role in the injured lung using a rat model of lung contusion (LC). Bronchoalveolar lavage fluids (BALF) were obtained at various time points for up to 168 h after LC or sham procedure. Enzyme activities, ELISA and Western blots indicated enzymatically active 20S, the 19S subunit Rpt5 and ubiquitin in BALF. 20S and ubiquitin increased significantl y after LC, peaked at 24 h and normalized within 168 h. Mg 2+ /ATP-dependent peptidase activities were detectable 6-24 h after LC. BALF after LC also contained ubiquitin-protein-ligase activity. Addition of Mg 2+ /ATP to BALF after LC led to significant proteolysis and could be prevented with epoxomicin and EDTA. These data suggest for the first time that the Mg 2+ /ATP-dependent 26S proteasome complex exists outside the cell, is released into the lung epithelial lining fluid after LC and contribute s to the proteolysis of the bulk of protein in the alveolar space of the injured lung. We infer that proteasome complexes may have a pathophysiological role during lung edema clearance., M. Majetschak, L. T. Sorell, T. Patricelli, D. H. Seitz, M. W. Knöferl., and Obsahuje bibliografii
Antiendothelial cell antibodies (AECA) have been detected by flow cytometry analysis in 23 out of 80 patients with connective tissue diseases. Ten out of 19 serum samples from patients with systemic lupus erythematosus (SLE) were positive. These antibodies were not detectable in healthy donors. We examined the capacity of serum samples to induce endothelial cell activation by modulating cell adhesion molecule expression on human umbilical vein endothelial cells. We found that sera from both AECA-positive and AECA-negative patient groups induced a significantly higher expression of E-selectin compared to healthy controls (P<0.05). There were no differences in the ICAM-1 on VCAM-1 expression. Our data suggest that increased E-selectin expression in activated endothelium in patients with various connective tissue disorders is not related to the production of AECA., M. Horváthová, E. Jahnová, Š. Nyulassy., and Obsahuje bibliografii
a1_The wide chemical diversity of estrogenic compounds precludes an accurate prediction of estrogenic activity on the basis of chemical structure or radioimmunological assay and thus requires that the potency of these compounds is defined by bioassay. The mammary duct growth response in intact prepubertal and adult gonadectomized female and male mice of the C3H/Di strain was used to assess the estrogenicity of synthetic compounds or their derivatives. The vehicle for tested compounds should be free of estrogenic and other hormonal effects. Olive oil or sunflower oil exerted estrogenic activities and were thus unsuitable as vehicles for the tested compounds. The absence of estrogenic activity, high solubility of different steroid hormones, and the low incidence of the inflammatory reactions at the injection site were achieved by using a vehicle containing benzyl alcohol, benzyl benzoate, butylhydroxyanisole, butylhydroxytoluene, ethyl oleate and ethanol. The bioassay was primarily designed to examine the effect of tested compounds on mammogenesis. The duration of hormone treatment was chosen to be long enough for induction of duct growth but too short to induce lobuloalveolar differentiation. Females were treated for 10 days, males for 15 days. The proportional volume occupied by mammary epithelial structures was estimated by the modified Chalkley's technique. The mean coefficient of variation of quantitative evaluation of 10 different mammary glands obtained by two operators varied between 3.2 and 17.4 %. The mean coefficient of variation of quintuplicate determinations of each mammary gland by one operator was 10.1 %, and 11.1 % by the other. The correlation coefficient between results of two operators was 0.994. Estrogens are primarily defined by their ability to increase the mitotic activity of female secondary sex organs., a2_However, our results have shown that progesterone alone, if administered in a high dose, stimulates mammary growth in both intact prepubertal and OV-X female mice similarly as the synthetic progestatial steroid norethindrone with inherent estrogenic properties. In contrast, progesterone alone had no effect, in young intact or adult castrated males, but norethindrone did stimulate mammary growth. These results demonstrated that the mammary gland of males is a suitable model for estrogen screening., J. Škarda., and Obsahuje bibliografii
The aim of our study was to investigate adrenocortical function in the context of disease activity and inflammatory status in premenopausal RA females. Adrenal glucocorticoid and androgen responses to the 1 μg ACTH 1-24 test were investigated in 23 premenopausal RA and in 15 age- and BMI-matched healthy females. Twelve RA patients were on low-dose prednisone (<8.5 mg/day). Patients with DAS28>3.2 had lower (p<0.05) total plasma cortisol, 17-hydroxyprogesterone, dehydroepiandrosterone and androstenedione responses in the ACTH test compared to healthy controls. Patients with DAS28>3.2 had lower (p<0.05) dehydroepiandrosterone response in the ACTH test compared to patients with DAS28≤3.2. C-reactive protein (CRP), DAS28, and interleukin (IL)-6 negatively correlated with androstenedione response to ACTH 1-24. Responses of all measured adrenal steroids were lower (p<0.05) in patients on low-dose glucocorticoids compared to healthy controls. RA patients not treated with glucocorticoids had lower total cortisol response (p=0.038) but did not differ in free plasma cortisol in the ACTH test. The results indicate an association of increased disease activity with a decrease in adrenal androgen production in RA and normal cortisol bioavailability in patients not treated with glucocorticoids., R. Imrich, M. Vlcek, J. Kerlik, M. Vogeser, F. Kirchhoff, A. Penesova, Z. Radikova, J. Lukac, J. Rovensky., and Obsahuje bibliografii
Cardiovascular disease is a major cause of morbidity and mortality in young adults with end-stage renal disease (ESRD), but its basis is still not well understood. We therefore evaluated the determinants of atherosclerosis in children with ESRD. A total of 37 children with ESRD (with 31 who had undergone transplantation) were examined and compared to a control group comprising 22 healthy children. The common carotid intimamedia thickness (CIMT) was measured by ultrasound as a marker of preclinical atherosclerosis. The association of CIMT with anthropometrical data, blood pressure, plasma lipid levels, and other biochemical parameters potentially related to cardiovascular disease was evaluated. Children with ESRD had significantly higher CIMT, blood pressure, and levels of lipoprotein (a), urea, creatinine, ferritin, homocysteine, and serum uric acid as well as significantly lower values of apolipoprotein A. The atherogenic index of plasma (log(triglycerides/HDL cholesterol)) was also higher in patients with ESRD; however, this difference reached only borderline significance. In addition, a negative correlation was found between CIMT and serum albumin and bilirubin in the ESRD group, and this correlation was independent of age and body mass index. In the control group, a significant positive correlation was observed between CIMT and ferritin levels. Factors other than traditional cardiovascular properties, such as the antioxidative capacity of circulating blood, may be of importance during the early stages of atherosclerosis in children with endstage renal disease., H. M. Dvořáková ... [et al.]., and Obsahuje seznam literatury
Increased homocysteine levels in serum are typical features of neurodegenerative brain diseases including hydrocephalus. The most frequent therapeutic approach consists of the insertion of a shunt, connecting the brain ventricles to an alternative drainage site. To decide whether the patient should undergo this, the lumbar drainage test is usually carried out to distinguish patients who can benefit from the shunt insertion. In searching for other potential biochemical markers for shunt indication we determined homocysteine levels in CSF during the lumbar drainage test. Homocysteine in CSF was measured during the 5-day lumbar drainage test in 27 patients with normal-pressure hydrocephalus (NPH) and in 25 patients with excluded hydrocephalus. A novelized gas chromatography method with flame ionization detection (GC-FID) was developed and evaluated. During the first two days of lumbar drainage, the levels of CSF homocysteine in NPH patients were significantly higher compared to the controls, while on the fifth day, the homocysteine levels in patients with hydrocephalus reached the level of controls. Determination of CSF homocysteine in patients with confirmed or suspected hydrocephalus may serve as an independent marker for deciding on their further treatment strategy., L. Sosvorová, J. Bešťák, M. Bičíková, M. Mohapl, M. Hill, J. Kubárová, R. Hampl., and Obsahuje bibliografii