Together with the development of peritoneal dialysis (PD), appropriate animal models play an important role in the investigation of physiological, pathophysiological and clinical aspects of PD. However, there is still not an ideal experimental PD animal model. In this study, 45 Sprague-Dawley rats were divided into three groups. Grou p 1 (n=15) was receiving daily peritoneal injection through the catheter connected to the abdominal cavity, using PD solution containing 3.86 % D-glucose. Group 2 (n=15) was receiving daily peritoneal injection of 0.9 % physiological saline through a catheter. Group 3 (n=15), which was subjected to sham operation, served as controls. Our results showed that WBC counts in peritoneal effluent of Group 1 were slightly higher than those of Group 2 and control group, respectively (p<0.05). However, there was no episode of infection in any group. In addition, there was no significant difference in neutrophils fractions among these three groups. Hematoxylin-eosin and Masson’s trichrome staining demonstrated a dramatic increase in thickness of the mesothelium-to-muscle layer of peritoneum exposed to high glucose (Group 1) compared to Group 2 and controls (p<0.01). These data indicated that we established a novel rat model of PD with a modified catheter insertion method. This model is more practical, easy to operate, not too expensive and it will facilitate the investigate of long-term effects of PD., Y.-M. Peng ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
In order to understand better Cd resistance in soybean, Dongying wild soybean treated with different Cd concentrations were evaluated. The biomass, chlorophyll (Chl) content, leaf color, Chl a fluorescence parameters, photosynthesis parameters, and Cd contents were determined. Our results showed that when Cd concentration was ≤ 2 kg m-3, no significant decrease in biomass, photosynthetic parameters, and maximal photochemical efficiency of PSII was observed. This indicated that Dongying wild soybean resisted Cd toxic effects under such conditions. In addition, atomic absorption experiment results demonstrated that when Cd concentration was ≤ 0.5 kg m-3, the accumulation of Cd in wild soybean was lower in roots than that in shoots, while the accumulation of Cd was higher in roots than that in shoots when Cd concentration was ≥ 1 kg m-3. Therefore, Dongying wild soybean showed a certain resistance to Cd and could serve as a valuable germplasm resource for improving the breeding of
Cd-resistant soybean., L. Liu, Y. K. Shang, L. Li, Y. H. Chen, Z. Z. Qin, L. J. Zhou, M. Yuan, C. B. Ding, J. Liu, Y. Huang, R. W. Yang, Y. H. Zhou, J. Q. Liao., and Obsahuje bibliografii
a1_To determine how the use of a given rootstock can influence the functioning of the photosynthetic apparatus of the scion under salt stress, the growth, gas exchange, photosystem II (PSII) efficiency, xanthophyll cycle, and chloroplast ultrastructure of nongrafted,
self-grafted, and pumpkin-grafted (hereafter referred to as rootstock-grafted) cucumber (Cucumis sativus L.) plants were investigated at day 15 after being treated with 90 mM NaCl. The reductions in plant growth of the rootstock-grafted plants were lower than those of the nongrafted and self-grafted plants under 90 mM NaCl. The net photosynthetic rate, stomatal conductance, maximal and effective quantum yield of PSII photochemistry, photochemical quenching coefficient, and effective quantum-use efficiency of PSII in the light-adapted state of the nongrafted and self-grafted plants were significantly decreased under 90 mM NaCl. However, these reductions were alleviated when the cucumber plants were grafted onto the pumpkin (Cucurbita moschata Duch.) rootstock. The intercellular CO2 concentrations were significantly increased in the nongrafted and self-grafted plants under 90 mM NaCl, whereas it was decreased in the rootstock-grafted plants. Nonphotochemical quenching (NPQ) and the deepoxidation state of the xanthophyll cycle were significantly increased under 90 mM NaCl, particularly in the rootstockgrafted plants, suggesting the rootstock-grafted plants had higher potential to dissipate excess excitation energy and reduce the probability of photodamage to PSII. Under 90 mM NaCl, the number of grana was reduced, the thylakoids were swollen, and starch granules accumulated in all plants. However, the damage of chloroplast ultrastructure was alleviated in the rootstock-grafted plants., a2_Taken together, the use of C. moschata rootstock alleviated salt stress in cucumber plants by delaying photoinhibition, probably due to a lower incidence of both stomatal and nonstomatal factors limiting photosynthesis., Z. X. Liu ... [et al.]., and Obsahuje bibliografii
The effect of CO2 increase on gas exchange and water-use effíciency (WUE) in three temperate deciduous species (Fagus crenata, Ginkgo biloba and Alnus firma) under gradually-developing drought-stress was assessed. Seedlings were grown within transparent open-top cabinets and maintained for 4 monťhs at mean CO2 concentrations of either 350 (ambient; C350) or 700 pmol moT’ (elevated; C700) and combined with five water regimes [leaf water potential, higher than -0.3 (well- watered), -0.5 and -0.8 (moderate drought), -1.0 and lower than -1.2 MPa (serious drought-stress)]. Increase in CO2 concentration induced a 60 % average increase in net photosynthetic rate (P^) under well-watered conditions. The effect of C700 became more pronounced with drought stress established, with an 80 % average increase in at as low as -0.8 MPa; leaf conductance to water vapour transfer (gs) and transpiration rate (£), however, were significantly decreased. Consequently, WUE increased under drought, through drought stress affected potential E sooner than potential P^. The interaction of CO2 x drought stress on WUE was significant in that Pn was stimulated while E in C700 enriched plants resembled that of C350 plants under drought. Hence if a doubling of atmospheric CO2 concentration occurs by the mid 2U* century, then greater P^ in F. crenata, G. biloba and^. firma may be expected and the drought susceptibility of these species will be substantially enhanced.
In previous studies, it has been shown that recombinant human neuregulin-1(rhNRG-1) is capable of improving the survival rate in animal models of doxorubicin (DOX)-induced cardiomyopathy; however, the underlying mechanism of this phenomenon remains unknown. In this study, the role of rhNRG-1 in attenuating doxorubicin-induce apoptosis is confirmed. Neonatal rat ventricular myocytes (NRVMs) were subjected to various treatments, in order to both induce apoptosis and determine the effects of rhNRG-1 on the process. Activation of apoptosis was determined by observing increases in the protein levels of classic apoptosis markers (including cleaved caspase-3, cytochrome c, Bcl-2, BAX and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining). The activation of Akt was detected by means of western blot analysis. The study results showed that doxorubicin increased the number of TUNEL positive cells, as well as the protein levels of cleaved caspase-3 and cytochrome c, and reduced the ratio of Bcl-2/Bax. However, all of these effects were markedly antagonized by pretreament with rhNRG-1. It was then further demonstrated that the effects of rhNRG-1 could be blocked by the phosphoinositole-3-kinase inhibitor LY294002, indicating the involvement of the Akt process in mediating the process. RhNRG-1 is a potent inhibitor of doxorubicin-induced apoptosis, which acts through the PI3K-Akt pathway. RhNRG-1 is a novel therapeutic drug which may be effective in preventing further damage from occurring in DOX-induced damaged myocardium., T. An, ... [et al.]., and Obsahuje seznam literatury