In morphological and biochemical studies we demonstrated that the development of eight-day old dark-grown beán seedlings was drastically influenced by prolonged irradiation with far red (FR) irradiation. The synthetic processes associated with leaf expansion were fiilly active, but the accumulation of chJorophyll (Chl) was very slow and the development of the photosynthetic apparatus was much prolonged. The capacity for oxygen evolution and photophosphorylation began at about the 2''‘* day. Low temperature spectroscopy showed the accumulation of three Chl a forms with absorption maxima at 670, 677 and 683 nm from the veiy beginning of the greening process and the appearance of two longer wavelength forms (with maxima at 690 and 698 nm) at the onset of photosynthetic activity. Electron microscopy showed unfiised stacks of primary thylakoids without grana formation. When the FR treated seedlings were subsequently placed in "white light", grana differentiated from these primary thylakoids.
Changes of chlorophyll (Chl) a fluorescence and photosynthetic pigment contents were analysed in galled leaves (visibly damaged and undamaged parts) and intact leaves. The values of minimal fluorescence of the dark-adapted state, maximal quantum yield of PSII photochemistry, effective quantum yield of PSII photochemical conversion, and photochemical quenching coefficient decreased in Ulmus pumila L. leaves galled by Tetraneura ulmi (L.) and in U. glabra Huds. galled by Eriosoma ulmi (L.). Colopha compressa (Koch.) feeding affected these parameters only in damaged parts of U. laevis Pall. galled leaves. The increasing number of T. ulmi galls progressively decreased photosynthetic performance. In gall tissues of all analysed aphid species, the lowest photosynthetic pigment content was found, indicating that the photosynthetic capacity must have been low in galls. Significant reduction of Chl and carotenoid contents were observed in damaged and undamaged portions of galled leaves only in the case of T. ulmi feeding., K. Kmieć, K. Rubinowska, W. Michałek, H. Sytykiewicz., and Obsahuje bibliografii
Experiments were conducted to study the effect of goldthioglucose (GTG) upon the processes associated with lipid peroxidation. The glucose-6-phosphate dehydrogenase activity (G6PD; E.C.1.1.1.49) in red blood cells (RBC) and the amount of malonaldehyde precursors (MDA) per gram of brain, liver and kidney were determined. Adult mice received i.p. injections for three consecutive days of either saline (controls) or GTG dissolved in saline, in a dose of 0.10 mg.g-1 or 0.15 mg.g-1 b.w. In mice receiving higher dose of GTG the G6PD activity was significantly increased (349.38± 17.46 mU.10-9 RBC compared to 258.2± 14.46 mU.10-9 RBC in control animals). The content of MDA precursors rose significantly from 4.8± 0.81 m mol.g-1 of the liver in controls to 8.12± 1.41 m mol.g -1 and 7.88± 0.51 m mol.g-1 and from 18.71± 1.01 m mol.g-1 of the kidneys in controls to 24.25± 1.25 m mol.g-1 and 24.88± 1.7 m mol.g-1 respectively. The GTG-induced higher levels of MDA precursors and increased G6PD activity in RBC corresponds to the rise in lipid peroxidation and its participation in producing the lesions after experimental and therapeutic use of gold-containing substances seems possible., D. Košťová, E. Michnová., and Obsahuje bibliografii
Group scan sampling and focal animal sampling was used to evaluate the relationship between the vigilance and group size of Mongolian gazelle (
Procapra gutturosa) from July to August 2012 around Lake Dalai, Inner Mongolia, China. We recorded 348 groups, including 107 mixed groups, 54 male groups, and 187 female groups with juveniles. The total number of individuals observed was 2026, including 4 solitary males, and the group average size was 5.76 individuals. The index of the models for curve fitting revealed that the power model Y= 2291.40–0.821 (R2 = 0.846, P = 0.013, Y
= vigilance distance and X = group size) was the best-fit model to represent
the relationship between vigilance distance and group size. The cubic model
Y = 108.1 – 16.95X + 1.09X2 – 0.023X3 (R2 = 0.826, P = 0.019, Y = vigilance rate and X = group size) was the best-fit model to represent the relationship between vigilance rate and group size. While, the logarithmic model Y =35.84 – 6.26lnX (R2 = 0.792, P = 0.024, Y = vigilance time and X = group size) was the best-fit model to represent the relationship between individual vigilance time and group size. Results indicate that vigilance rate, individual vigilance
time, and vigilance distance of Mongolian gazelle decreased significantly with increasing group size. Our research provides data on Mongolian gazelles’ vigilance and which will further benefit gazelle conservation.
The average soil temperature was significantly lower in plots covered with hay. Hay mulching, however, did not increase significantly the total number of soil micro-arthropods collected using a soil pin trap and a soil sampler. Significant increases in the number of individuals was recorded only for certain groups. 64% of all the arthropods collected using soil pin traps were collected in hay-covered plots and 36% in control plots. This increase was statistically significant for the orders Entomobryomorpha and Poduromorpha of the subclass Collembola and surface-dwelling (epigeic) Coleoptera. For the samples collected using the soil sampler, 57% of the specimens were collected from hay-covered plots and 43% from control plots. As for the pin traps this was reflected in differences in the numbers of the orders Entomobrhyomorpha and Poduromorpha of the subclass Collembola and Pauropoda, collected in the treated and control plots. We conclude that mulching affected the different arthropod groups differently., Péter Dudás, László Menyhárt, Csongor Gedeon, Gergely Aambrus, Ferenc Tóth., and Obsahuje bibliografii
Cholestasis is characterized by the elevation of serum total bile acids (TBA), which leads to the production of both free radicals and oxidative stress. Although they do not share the same mechanisms, membrane glycosphingolipids (GSL) and the antioxidant enzyme heme oxygenase-1 (HMOX1) both act against the pro-oxidative effect of TBA. The aim of the study was to assess the role of HMOX on GSL redistribution and composition within hepatocytes in the rat model of estrogen-induced cholestasis. Compared to the controls, an increase of total gangliosides in the liver homogenates of the cholestatic group (P=0.001) was detected; further, it paralleled along with the activation of their biosynthetic b-branch pathway (P<0.01). These effects were partially prevented by HMOX activation. Cholestasis was accompanied by a redistribution of GM1 ganglioside from the cytoplasm to the sinusoids; while HMOX activation led to the retention of GM1 in the cytoplasm (P=0.014). Our study shows that estrogen-induced cholestasis is followed by changes in the synthesis and/or distribution of GSL. These changes are not only triggered by the detergent power of accumulated TBA, but also by their pro-oxidant action. Increases in the antioxidant defenses might represent an important supportive therapeutic measure for patients with cholestatic liver disease., T. Petr, V. Šmíd, V. Kučerová, K. Váňová, M. Leníček, L. Vítek, F. Šmíd, L. Muchová., and Obsahuje bibliografii
Several authors have reported the association of postprandial hypertriglyceridemia with oxidative stress, systemic inflammation and endothelial dysfunction. Our aim was to investigate the effect of high-calorie meal on blood markers of oxidative stress and endothelial dysfunction and the association of APOA5-1131T/C and -250G/A hepatic lipase (HL) polymorphisms with postprandial triglyceride response. This study included 102 healthy male volunteers. All participants consumed a high-calorie meal (823 calories, 50 g fat, 28 g protein, 60 g carbohydrates). Total cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, hsCRP, TAS and ICAM-1 were measured at fasting state and postprandially. APOA5-1131T/C and -250G/A HL polymorphisms were also determined. Postprandial triglycerides were significantly increased (1.4 (1.1-2.1) vs. 2.4 (1.9-3.3) mmol/l, P<0.001). Average triglyceride increase was 1.0±0.7 mmol/l (65 %). Concentration of triglycerides, HDL- cholesterol, LDL-cholesterol, TAS and ICAM-1 differed significantly between the fasting state and postprandial measurements (P<0.001). However, those differences were within the limits of analytical imprecision. Other parameters did not change 3 h after the meal. Triglycerides response did not differ respective to the APOA5 and HL polymorphisms. Family history of hypertension and acut e myocardial infarction were associated with higher postprandial triglyceride concentrations. Postprandial hypertriglyceridemia is not associated with increased concentrations of hsCRP, TAS and ICAM-1. Furthermore, APOA5-1131T/C and -250G/A HL polymorp hisms are not associated with different postprandial triglyceride response., S. Kackov ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Results of the effect of subsidence of the Little Hungarian Plain on vertical movement of the riverbed and the downstream riverbed slope changes of the regulated flowchannel of Danube are presented. Subsidence of the flowchannel is also affected by the tectonic movements. The subsidence rate is attenuated by the andesitic Börzsöny and Visegrád Mountains since they function as natural barriers for the river. In the eastern vicinity of the Börzsöny and the Mátra, where the river flows in loose, unconsolidated sediments, the deepening of the flowchannel is considerable. and Príspevok prezentuje výsledky účinku poklesu Malej Uhorskej nížiny (geogr.) na vertikálny pohyb riečneho koryta a na zmeny pozdĺžneho sklonu upraveného koryta Dunaja. Pokles koryta toku je ovplyvnený aj tektonickými pohybmi. Intenzita poklesu je tlmená účinkom andezitovej línie horských celkov Börzsöny a Visegrád, ktoré pôsobia na rieku ako prírodné bariéry. Na východ od týchto horských celkov, kde rieka preteká cez voľnejšie uložené, nespevnené usadeniny, vyskytuje sa značné prehĺbenie riečneho koryta.
The effect of hormonal stimulation with FSH injection in the doses of 18 mg (360 IU) and 24 mg (480 IU FSH) on the levels of plasma catecholamines (dopamine, norepinephrine and epinephrine) was studied by radioenzymatic methods during synchronized oestrous cycles of the sheep. Catecholamines were determined in the blood plasma before and 24, 48, 96 and 120 hours after application of FSH. It follows from the results that the levels of plasma dopamine increased significantly (p<0.001) 24 and 48 hours after FSH application. Furthermore, the levels of dopamine (DA) during the other time intervals observed, compared with those of controls before hormonal stimulation, remained at a higher level. A lower dose of the hormone (18 mg) had a more pronounced effect on changes in the levels of plasma dopamine. Norepinephrine (NE) did not exhibit any significant changes in comparison with the plasma levels of dopamine in the sheep after hormonal stimulation with FSH. A statistically significant increase in plasma norepinephrine was recorded 24 hours after administration of 18 or 24 mg FSH. During the other time intervals observed, its levels did not differ from the control values. Plasma epinephrine (E) showed a significant increase 24 and 48 hours after FSH application but not later. The effect of FSH on plasma catecholamine levels was not dose-dependent and their increase was pronounced especially in the period of ovulation.
Various protocols may be used for acute pancreatitis treatment. Recently, the benefit of hyperbaric oxygen (HBO) has been demonstrated. To clarify the mechanism of HBO on the process of the acute pancreatitis, we determined the levels of antioxidant enzymes in an acute pancreatitis model. Forty-five Sprague-Dawley rats were randomly divided into three groups: Group I: sham group (n=15), Group II: pancreatitis group (n=15), Group III: pancreatitis group undergoing HBO therapy (n=15). HBO was applied postoperatively for 5 days, two sessions per day at 2.5 fold absolute atmospheric pressure (ATA) for 90 min. Superoxide dismutase (Cu/Zn-SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH Px) activity were measured in pancreatic tissue and erythrocyte lysate. MDA and GSH Px were also determined in plasma. In addition, amylase levels were measured in the serum. While serum amylase levels and MDA values in erythrocyte, plasma and pancreatic tissue were decreased, the levels of GSH Px and SOD were found to be significantly increased in the Group III as compared to those of the Group II. The findings of our study suggest that HBO has beneficial effects on the course of acute pancreatitis and this effect may occur through the antioxidant systems., M. Yasar, S. Yildiz, R. Mas, K. Dundar, A. Yildirim, A. Korkmaz, C. Akay, N. Kaymakcioglu, T. Ozisik, D. Sen., and Obsahuje bibliografii