新疆高钠煤中钠的赋存形态及其对燃烧过程的影响

采用不同萃取液对中国新疆高钠煤进行逐级萃取实验,利用离子色谱仪和电感耦合等离子体原子发射光谱仪对萃取制得的滤液和固体煤样进行相应的元素分析,并通过逐级萃取后煤样的着火温度、燃尽温度和综合燃烧特性指数来分析高钠煤中不同存在形式钠对其燃烧特性的影响.结果表明,中国新疆高钠煤中的钠主要以水溶钠为主,有机钠和不可溶钠含量较少.影响高钠煤中水溶钠含量的主要因素有煤颗粒内部孔隙结构和颗粒粒径,且高钠煤中有机钠在各个粒径范围都保持了相对稳定的含量.煤种不同会导致煤中水溶钠与水溶氯的存在形式不同.煤中水溶钠的存在不利于高钠煤的着火温度和燃尽温度的降低与燃烧特性的提高,相反煤中的有机钠却对其具有促进作用.     

Antioxidant activity of phenolic compounds from extracts of Eucalyptus globulus and Melaleuca styphelioides and their protective role on D-glucose-induced hyperglycemic stress and oxalate stress in NRK-49Fcells

Phytochemicals serve as potential therapeutic agents for the prevention and treatment of diseases. In this study, we elucidate the renoprotective activity of compounds isolated from Eucalyptus globulus and Melaleuca styphelioides extracts in glucose- and oxalate-challenged NRK-49F cell model. The antioxidant potential of isolated compounds was evaluated based on their effect on antioxidant enzyme activities and lipid peroxidation levels. The results demonstrated that exposure of NRK-49F cells to glucose and oxalate stress augmented cell damage and attenuated antioxidant enzyme activities. The phytochemicals 2,2,8-trimethyl-6-formyl-chrom-3-ene-7-O-β-D-glucopyranoside, Cornusiin B and tellimagrandin I treatment restored antioxidant enzyme activity, significantly lowered lipid peroxidation levels and effectively protected cells from glucose and oxalate stress equivalent to the known antioxidant, N-acetyl cysteine. Pterocarinin A significantly reversed cellular damage owing to glucose stress. In conclusion, the compounds isolated from E. globulus and M. styphelioides showed potential cytoprotective and anti-oxidative property against glucose- and oxalate-induced oxidative stress in NRK-49F cells.     

Protective activity of an anthocyanin-rich extract from bilberries and blackcurrants on acute acetaminophen-induced hepatotoxicity in rats

Acetaminophen (N-acetyl-p-aminophenol, APAP) overdosage can produce fatal centrilobular hepatic necrosis in humans. The present study attempted to investigate the protective effect of an anthocyanin-rich extract from bilberries and blackcurrants (AE) against APAP-induced acute hepatic damage in rats. Treatment with AE normalised blood activities of glutamate oxaloacetate and glutamate pyruvate transaminase and prevented APAP-induced plasmatic and tissutal alterations in biomarkers of oxidative stress, probably due to various bioproperties of the components of the extract.     

Chemical constituents and protective effect of Ficus ingens (Miq.) Miq. on carbon tetrachloride-induced acute liver damage in male Wistar albino rats

The aim of the present study was to investigate the chemical constituents and hepatoprotective effect of Ficus ingens (Miq.) Miq. (Moraceae) extract against carbon tetrachloride-induced acute liver damage in male Wistar albino rats. The ethanol extract of F. ingens, was subjected to phytochemical study. In addition, its acute and sub-chronic toxicities were assessed. Eight compounds were isolated from this plant and identified as β-sitosterol, β-sitosterol glucoside, chryasophanol, 7-hydroxy-2,5 dimethyl chromen-4-one, quercetin, Aloe emodin glucoside, rutin and Patuletin-3′-O-methyl-3-O-rutinoside. The structure elucidation was based on ¹H and ¹³C NMR, proton–proton correlation spectroscopy (¹H–¹H Cosy), distortionless enhancement by polarization transfer (DEPT), Heteronuclear Multiple-Quantum Correlation (HMQC), and heteronuclear multiple bond correlations spectrum (HMBC). Hepatotoxicity induced with CCl₄ was evidenced by elevation of liver marker enzymes (ALT, AST, ALP and LDH) and TB content in serum. In addition, antioxidant enzymes were drastically inhibited with significant reduction of GSH and increased LPO in liver homogenate of CCl₄-intoxicated rats. Pre-treatment with F. ingens (200 and 400 mg/kg) and silymarin (50 mg/kg) avoided the changes observed in CCl₄-intoxicated rats. In conclusion, the ethanol extract of F. ingens showed protective activity against liver injury, which might be developed into a new hepatoprotective agent.     

Nephroprotective effects of 4-4(hydroxyl-3 methoxyphenyl)-2-butane against sodium tellurite induced acute kidney dysfunction by attenuating oxidative stress and inflammatory cytokines in rats

The aim of this study was to elucidate the protective action mechanism of 4-4(hydroxyl-3-methoxyphenyl)-2-butane against Sodium tellurite (ST) induced nephrotoxicity in rats. ST is a hazardous substance used in metallurgical and glassware industries, but its renal toxicities have not been well established before. Rats were distributed into four groups, six rats contain in each group. Normal control group given only vehicles only, toxic group given ST 8.5 mg/kg p o, treated groups given ST and 4-(hydroxyl-3-methoxyphenyl)-2-butane(100 mg/kg bwt), and positive control given only treatment drug 4-(hydroxyl-3-methoxyphenyl)-2-butane (100 mg/kg bwt) daily for 14 days. ST administration increases an alteration in biochemical, oxidative stress, cytokines markers, and morphological changes in toxic group. When it was treated with 4-(hydroxyl-3- methoxyphenyl)-2-butane significantly (p < 0.5) restores all these changes such as biochemical markers, antioxidant, inflammatory cytokines, and histopathological improvements in treated group as compared to toxic group. No significant (p > 0.05) changes have been seen in positive control as compared to normal control. In conclusion, 4(hydroxyl-3 methoxyphenyl)-2-butane successfully defended the kidney from oxidative stress, inflammatory cytokines and necrosis against ST intoxication. Thus, significant improvements were reflected and confirms with the improvement in histopathological changes.     

Protective effects of grape seed extract fractions with different degrees of polymerisation on blood glucose,lipids and hepatic oxidative stress in diabetic rats

The purpose of this study was to evaluate the effect of grape seed procyanidin (GSPE) fractions with different degrees of polymerisation (DPs) on blood glucose, lipids and hepatic oxidative stress in diabetic rats. Diabetic rats received a daily oral supplement of GSPE with different DPs for 6 weeks. During this period, blood glucose, body weight and food intake were assessed weekly. At the end of the experiment, serum lipid and hepatic oxidative stress were assessed compared with those of rats that did not receive GSPE. GSPE significantly decreased blood glucose, serum lipids and hepatic oxidative stress. Moreover, these effects were significantly better in the groups administered the oligomeric rather than the polymeric forms. These results demonstrate that GSPE has a positive effect on diabetes in rats, and the oligomeric form of GSPE may be more protective than other forms.     

Amelioration of oxidative stress,inflammation and tumor promotion by Tin oxide-Sodium alginate-Polyethylene glycol-Allyl isothiocyanate nanocomposites on the 1,2-Dimethylhydrazine induced colon carcinogenesis in rats

BackgroundColorectal cancer (CRC) is a frequently diagnosed cancer that primarily affects the digestive system and an imperative cause of mortalities worldwide.ObjectiveIn this work, we formulated the Tin oxide-Sodium alginate-Polyethylene glycol-Allyl isothiocyanate nanocomposites (SAP-Ally-NCs) and investigated its anticancer role against the DMH-provoked CRC in rats.MethodologyThe formulated SAP-Ally-NCs were characterized different techniques. The CRC was provoked to the rats via injecting 20 mg/kg of DMH and then administered with the formulated SAP-Ally-NCs for 16 weeks. The bodyweight changes and the polyp’s incidences were detected and tabulated. The status of lipid peroxidation and antioxidant enzymes were studied by standard techniques. The inflammatory markers and xenobiotic enzymes level was scrutinized using respective kits. The mRNA expressions of various signaling molecules were examined by RT-PCR. The liver and colon tissues were examined microscopically to detect the histological changes.ResultsThe formulated SAP-Ally-NCs treatment appreciably improved the body weight gain and suppressed the polyp’s incidences in the DMH-challenged animals. SAP-Ally-NCs treated animals were demonstrated the notable reduction in the lipid peroxidation and inflammatory cytokines and elevated the antioxidant enzymes i.e. CAT and SOD activity. SAP-Ally-NCs administered animals exhibited the noticeable reduction in the expression of PCNA, cyclin-D1, iNOS, and COX-2 in the colon tissues. The histological findings also unveiled the therapeutic role of SAP-Ally-NCs.ConclusionIn conclusion, the SAP-Ally-NCs demonstrated the potent anticancer action against the DMH-provoked CRC in rats. In future, it could be a potent chemotherapeutic agent to the CRC.     

Expression of Cu,Zn-superoxide dismutase gene from <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> in <Emphasis Type="Italic">Pichia pastoris</Emphasis> and its resistance to oxidative stress

The gene for the Cu, Zn-superoxide dismutase (SOD) from the yeast Saccharomyces cerevisiae was cloned, characterized, and overexpressed in the methylotrophic Pichia pastoris. The sod gene sequence obtained is 465 bp and encodes 154 amino acid residues. The sod gene sequence was cloned into the pPIC9K vector, yielding pAB22. The linearized pAB22 DNA, digested with restriction enzyme SacI, was transformed into the genome of the GS115 strain of the yeast P. pastoris. The SOD was purified from the cultured yeast by ammonium sulfate precipitation and DEAE-cellulose column chromatography. This relatively simple purification method produced a single band on analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The overexpressed SOD protein was shown to have immunologically biologic activity and to be enzymatically active. The yeast overexpressing Cu, Zn-SOD appeared to be more resistant to oxidative stress such as paraquat, menadione, and heat shock.