Ganoderma Lucidum polysaccharide peptides protect kidney from renal ischemia reperfusion injury via counteracting oxidative stress

OBJECTIVE Ganoderma lucidum polysaccharide peptides(GLPP)have an anti-oxidant activity.The oxidative stress implicates in the pathogenesis of renal ischemia-reperfusion injury(RIRI).The objective of this study was to determine whether GLPP could attenuate RIRI via counteracting the oxidative stress.METHODS Mice subjected to uninephrectomy with the right kidney ischemia for 35 min and reperfusion for 24 hwere used to explore the protective activity of GLPP against RIRI.In GLPP-treated group,100mg·kg-1·d-1 of GLPP were intraperitoneally injected for 7dbefore the procedure.In vitro,NRK-52 Ecells subjected to hypoxia-reoxygenation(H/R)and tunicamycin were used to explore the protective effect of GLPP against oxidative stress.The mechanisms in which GLPP protected kidney from RIRI were studied using a series of physiological and molecular biological methods.RESULTS Kidneys undergone ischemia-reperfusion showed renal dysfunction and characteristic morphological changes including cellular necrosis,brush border loss,cast formation,vacuolization and tubular dilatation while these damages were significantly attenuated by GLPP treatment.The abnormal levels of MPO,MDA and SOD caused by renal ischemia-reperfusion were significantly reversed by GLPP treatment.More apoptotic cells were found in the renal ischemia-reperfusion group than the sham group whereas GLPP reduced apoptotic cells in the ischemia-reperfusion mice by21.75%(P<0.01).The GLPPs(25-1μg·mL)alleviated H/R induced cell viability loss by 20.12%(P<0.01)andΔφm dissipation by 27.3%(P<0.01)in vitro as well and its pretreatment dramatically reduced H/R and tunicamycin induced cell injury.CONCLUSION Our study found that GLPP had a protective effect on RIRI via its anti-oxidative capacity,which suggests that GLPP may be developed as a candidate drug for preventing acute kidney injury.

Occurrence of Haloacetic Acids in Drinking Water in Certain Cities of China

Objective Since haloacetic acids (HAAs), which are nonvolatile and of high carcinogenic risk, are common species of chlorinated disinfection by-products(DBPs) in drinking water, and little has been known in China, it is necessary to make a survey about the kinds and levels of HAAs in drinking water of the nation. Method HAAs were analyzed using gas chromatography with electron capture detector(GC/ECD) and relatively complex pretreatment process of sample was applied. Five main cities in different areas of China were chosen in the survey. Results Studies showed that the main species of HAAs in drinking water in China were DCAA and TCAA, ranging from 0.4 礸/L to 12.85 礸/L and from 0.56 礸/L to 10.98 礸/L, respectively. MBAA and DBAA were also detected in one city, ranging from 2.20 礸/L to 4.95 礸/L and 1.10 礸/L to 2.81 礸/L, respectively. Therefore, the contents of HAAs varied, usually no more than 25 礸/L. Based on the acquired data to date, it is known that the concentrations of HAAs in drinking water in China were surely under the limits of Sanitary Standard for Drinking Water Quality (China, 2001). Conclusion A wider survey of HAAs in drinking water should be conducted throughout the nation to get adequate data and information, the ultimate aim of which is to control HAAs pollution and keep the balance between microbiological safety insurance and chemical risk control, minimize the formation of DBPs and ensure the safety of water supply at the same time.

Analyses on Ignition-Proof Mechanics of AZ91D Alloy Added with Ce

Theoretical analysis on ignition-proof of AZ91D alloy added with Ce was studied. The effect of Ce on burning temperature was investigated. The burning temperature increases with increasing Ce by insulation work at different temperatures. The influence of Ce on maximum insulation work time was also studied. The maximum insulation work time increases with increasing Ce and decreases with the melting temperature. There is a tendency for Ce to concentrate on the surface of melti.ng AZ91D alloy. Ce will react with MgO and O2. The resultant will fill the cavity of MgO film to form multifilm. So the density of surface film of liquid Mg will increase to prevent burning.

Interaction between Bifunctional Dioxo Macrocyclic Polyamine Co(II) Complex and DNA in Metallomicellar System

The cleavage of DNA (pUC18) by lipophilic macrocyclic polyamine Co(II) complex was investigated in metallomicellar system. The results showed that the conversion of plasmid DNA (pUC18) increases with the increase of the concentration of complex under physiological conditions.

Lipopolysaccharide Could Be Internalized into Human Peripheral Blood Mononuclear Cells and Elicits TNF-α Release,but not via the Pathway of Toll-Like Receptor 4 on the Cell Surface

Lipopolysaccharide(LPS),the principal component of the outer membrane of Gram-negative bacteria,stimulates various cell types to release numerous proinflammatory mediators such as TNF-α,IL-6 and IL-12,which may damage cells and lead to organ injury,even sepsis and septic shock.Toll-like receptor 4(TLR4) has been identified as the receptor involved in the recognition of LPS,but the role of LPS uptake in activating signal transduction remains controversial.In the present study,TNF-α was used as a marker of macrophages/ monocytes activated by LPS,and CQ was used as an inhibitor of endosome mature in order to definitude what stage of the signal transduction elicited by LPS was interrupted.We found that there indeed existed internalization of LPS and internalization partially participated in LPS signaling since CQ inhibited cytokine release,and decreased accumulation of FITC-LPS in hPBMCs.In contrast,anti-hTLR4 antibody could decrease cytokine release,but had no inhibition on accumulation of FITC-LPS.This result revealed that inhibition of cytokine release was related to reduction of FITC-LPS accumulation in the cells.But TLR4 on the cell surface couldn't participate in internalization of LPS.Thus,LPS signaling and internalization couldn't be viewed as mutually independent processes.Cellular & Molecular Immunology.2004;1(5):373-377.